Academic literature on the topic 'MSG rats'
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Journal articles on the topic "MSG rats"
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Baskara, Angga, I. N. Arsana, and N. K. A. Juliasih. "GAMBARAN HISTOPATOLOGI HATI TIKUS WISTAR (Rattus norvegicus) PASCA PEMBERIAN MONOSODIUM GLUTAMAT." JURNAL WIDYA BIOLOGI 10, no. 01 (January 9, 2019): 68–75. http://dx.doi.org/10.32795/widyabiologi.v10i01.238.
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Monosodium glutamate (MSG) has been used very widely in the community as a food flavoring, and is thought to have a detrimental effect. This study aims to determine the effect of MSG on liver histopathology. 28 Wistar rats were used in this study. Rats were grouped into four groups: control (K), MSG-1 (MSG dose 1.5 mg / g bodyweight), MSG-2 (MSG dose 3.5 mg / g bw), and MSG-3 (MSG dose 4, 5 mg / g bw). MSG is given every day for 30 days. At the end of the treatment, the rat were euthanized and dissected for taking the liver. Histology preparation were made using the paraffin method and stained with Hematoxyclin Eosin (HE) staining. Kruskal Wallis and Mann Whitney test were used for statistical analysis. The results showed that the dose of MSG was 1.5; 3; and 4.5 mg / g bw causes liver damage with the same level of damage in the form of focused degeneration in one place. The higher the dose, the more degeneration of focused on one place which were found. Liver tissue damage scores in group K, MSG-1, MSG-2, and MSG-3 were 0; 0.4; 0.42857, and 0.45714. Conclusion, the administration of MGS has an effect on liver histopathology.
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Egbuonu, Anthony Cemaluk Chinedum, Emmanuel Obi, Chinedu P. Nwuke, Cynthia Uchechi Simon, Justina Utodinachi Oleghibe, Nnaemeka Raymond Ezenwafor, and Ebere Mercy Chukwu. "Monosodium Glutamate Plus Artemether-lumefantrine Overdose Altered Malondialdehyde, Total Protein and Albumin Concentration in Rats." Advanced Journal of Graduate Research 7, no. 1 (December 7, 2019): 70–79. http://dx.doi.org/10.21467/ajgr.7.1.70-79.
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This study aimed at assessing alterations in malondialdehyde, MDA, total protein and albumin concentration in the serum and liver homogenate of monosodium glutamate (MSG)-challenged rats co-treated with artemether-lumefantrine, AL. Methods involving colourimetric estimation were employed in thirty rats randomly grouped into six (n = 5) and for seven consecutive days, fed feed and water (Group A), AL therapeutic dose (Group B), AL overdose (therapeutic dose × 5) (Group C), MSG (8000 mg/kg body weight) (Group D), AL therapeutic dose plus MSG (Group E) or AL overdose plus MSG (Group F). Total protein concentration (2.64±0.09 g/dL, 2.81±0.14g/dL, respectively) in the liver homogenate of rats exposed to MSG (group D) or MSG plus AL overdose (group F) and malondialdehyde concentration in the liver homogenate of MSG plus AL overdose-fed rats (0.45±0.04 mg/ml) lowered (P<0.05) as against other groups. However, serum albumin concentration in MSG (2.59±0.13 g/dl) or AL overdose plus MSG (3.24±0.12 g/dl) fed rats was higher (P<0.05) compared to the control (2.02±0.04 g/dl). The Total protein: Albumin ratio lowered while the Albumin: total protein ratio increased in rats in MSG, AL overdose plus MSG or AL overdose groups compared with the control. Thus, the apparent MSG plus AL overdose-induced adverse influence on the studied parameters and samples of non-malarial infested rats could be via compromised liver-mediated protein metabolism capacity and bio-functions following possibly enhanced protein-malondialdehyde adduct formation in the rats.
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Sassaki, Kikue Takebayashi, Alberto Carlos Botazzo Delbem, Otoniel Antonio Macedo dos Santos, Carlos Eduardo Shimabucoro, Ana Cláudia de Melo Stevanato Nakamune, João César Bedran-de-Castro, and Ricardo Martins Oliveira-Filho. "Neuroendocrine alterations impair enamel mineralization, tooth eruption and saliva in rats." Pesquisa Odontológica Brasileira 17, no. 1 (March 2003): 5–10. http://dx.doi.org/10.1590/s1517-74912003000100002.
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Neonatal administration of monosodium glutamate (MSG) in rats causes definite neuroendocrine disturbances which lead to alterations in many organ systems. The possibility that MSG could affect tooth and salivary gland physiology was examined in this paper. Male and female pups were injected subcutaneously with MSG (4 mg/g BW) once a day at the 2nd, 4th, 6th, 8th and 10th day after birth. Control animals were injected with saline, following the same schedule. Lower incisor eruption was determined between the 4th and the 10th postnatal days, and the eruption rate was measured between the 43rd and the 67th days of age. Pilocarpine-stimulated salivary flow was measured at 3 months of age; protein and amylase contents were thereby determined. The animals treated with MSG showed significant reductions in the salivary flow (males, -27%; females, -40%) and in the weight of submandibular glands (about -12%). Body weight reduction was only about 7% for males, and did not vary in females. Saliva of MSG-treated rats had increased concentrations of total proteins and amylase activity. The eruption of lower incisors occurred earlier in MSG-treated rats than in the control group, but on the other hand the eruption rate was significantly slowed down. The incisor microhardness was found to be lower than that of control rats. Our results show that neonatal MSG treatment causes well-defined oral disturbances in adulthood in rats, including salivary flow reduction, which coexisted with unaltered protein synthesis, and disturbances of dental mineralization and eruption. These data support the view that some MSG-sensitive hypothalamic nuclei have an important modulatory effect on the factors which determine caries susceptibility.
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Gaspar, Renato Simões, Renata Ohana Alves Benevides, João Lucas de Lima Fontelles, Caroline Castro Vale, Lucas Martins França, Paulo de Tarso Silva Barros, and Antonio Marcus de Andrade Paes. "Reproductive alterations in hyperinsulinemic but normoandrogenic MSG obese female rats." Journal of Endocrinology 229, no. 2 (May 2016): 61–72. http://dx.doi.org/10.1530/joe-15-0453.
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Obesity and metabolic syndrome are the common causes of reproductive and fertility disorders in women. In particular, polycystic ovary syndrome, which is clinically characterized by hyperandrogenism, oligo/anovulation, and polycystic ovarian morphology, has been increasingly associated with metabolic disorders. However, given the broad interplay between metabolic and reproductive functions, this remains a field of intense research. In this study, we investigated the effect of monosodium l-glutamate (MSG)-induced obesity on reproductive biology of female rats. Newborn female rats were subcutaneously injected with MSG (4g/kg/day) or equiosmolar saline (CTR) each 2 days up to postnatal day (pnd) 10. On pnd 60, estrous cycle was evaluated using vaginal smears twice a day for 15 days, which showed MSG rats to be oligocyclic. Thereafter, animals were killed on estrous phase for blood and tissue collection. MSG rats had increased body mass, accumulation of retroperitoneal and visceral fat pads, and visceral adipocyte hypertrophy compared with CTR rats. MSG rats were also dyslipidemic and hyperinsulinemic but were normoglycemic and normoandrogenic. Ovarian morphology analysis showed that MSG rats had a two-fold decrease in oocyte count but a six-fold increase on ovarian follicular cysts, along with a higher number of total primordial and atretic follicles. Moreover, MSG rats had a four-fold increase in anti-Müllerian hormone immunohistochemical staining on antral follicles. Taken together, data presented here characterize MSG obesity as a unique model to study the metabolic pathways underlying reproductive disorders in the absence of overactivated hypothalamic–pituitary–gonadal axis.
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Nwanneka, Ofodile Lauretta, Abraham Abigail, Ayoade Yemisi, Adamu Governor Oniovosa Leonard, Ovioma Godwin Onoriode, Nwakanma Moses Ndubuisi Chikere, Bikomo Ojigho Ewenodere, Ikegwu Emmanual, and Ayodeji Ayo Adekunle. "Effect of the Aqueous Extract of Ganoderma lucidum on the Haematology, Oestradiol, Cholesterol and Protein Levels of Wistar Rats Fed with Monosodium Glutamate." Malaysian Journal of Pharmaceutical Sciences 18, no. 2 (November 30, 2020): 47–62. http://dx.doi.org/10.21315/mjps2020.18.2.4.
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Monosodium glutamate (MSG) at high concentration has been reported to alter the physiological and biochemical states of animals and humans. Ganoderma lucidum (G. lucidum) is a polypore mushroom reported to possess many medicinal attributes such as anticholesterolemia and the control of hormonal disorders. The present study investigated the effect of water extract of G. lucidum in the changes of haematology, oestradiol, cholesterol and protein levels of Wistar rats induced by MSG. Haematological analysis was determined from plasma, while oestrogen, serum total protein and cholesterol levels were determined from the serum of the rats. Results showed that MSG significantly raised the level of oestrogen (62.5 ± 0.28 pg/mL) in the rats which was significantly reduced in the rats fed with MSG for 30 days before treating them with the extracts of G. lucidum (30.85 ± 12.94 pg/mL–44.15 ± 0.92 pg/mL) and in rats fed concurrently with MSG and G. lucidum. The cholesterol level was significantly reduced in the rats treated with MSG and G. lucidum (200 mg/kg) concurrently compared to rats fed with MSG alone. The white blood cell (WBC) and red blood cell (RBC) levels were within normal in rats fed with both MSG and G. lucidum as in the control group while the rats fed with MSG only had low WBC, neutrophil (NEU) and RBC. This could imply that G. lucidum ameliorates the effect of MSG on serum oestrogen, serum cholesterol, WBCs, NEU, platelets and lymphocytes.
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Ogunlabi, Olugbenga O., Bukunola O. Adegbesan, Adedayo A. Adebisi, and Emmanuel O. Ajani. "PRE-TREATMENT WITH PHYLLANTHUS AMARUS STALLS DYSLIPIDEMIA AND UTERINE TOXICITY IN MONOSODIUM GLUTAMATE ADMINISTERED RATS." African Journal of Science and Nature 9 (November 10, 2020): 1. http://dx.doi.org/10.46881/ajsn.v9i0.165.
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Studies have implicated intake of monosodium glutamate (MSG) in fibroid development, but reports on the correlation between dyslipidemia and fibroid induction with an intake of MSG are inconsistent. This study investigates the risk of dyslipidemia in MSG intake and the therapeutic effect of administration of Phyllanthus amarus. Forty adult female Wistar rats randomize to 5 groups of 8 rats each were used. MSG was administered continuously to groups 2-5 at 200 mg/Kg body weight for 28 days. After 28 days, blood was withdrawn from rats in groups1, 2 and 3after anaesthetizing with diethyl ether. They were then sacrificed and the uterus, kidney and liver excised. MSG administrations were later discontinued in the remaining groups of rats, and P. amarus leaves extract was administered daily to group 4. Treatments were later continued for the next 28 days after which the rats were sacrificed. Total cholesterol (TC), Low-density lipoprotein (LDL-c), High-density lipoprotein (HDL-c), triglyceride, artherogenic (AI) and coronary risk index (CRI), glucose and total protein were then determined in the serum. The organs were also weighed, and the uterus was used for histopathology studies. Results indicate that serum cholesterol, LDL-c, triglycerides, API, CRI and glucose were raised with MSG administration whereas; HDL-c was reduced. Co-administration of P. amarus with MSG prevented these alterations. Withdrawal of MSG without treatment and administration of P. amarus after MSG administration also reduced the cholesterol, triglyceride, LDL, AI and CRI. Although the final body weights and uterine weight ratio were increased with MSG administration and co-administration of P. amarus with MSG prevented these alterations, no observable difference was observed in the histology of the uterine tissues. The study suggests that MSG administration is positively correlated with dyslipidemia and uterine toxicity. Results also show that co-administration of P. amarus with MSG may offer protection against these metabolic changes
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Dalkin, A. C., J. A. Duncan, S. Regiani, and J. C. Marshall. "Reduction of pituitary GnRH receptors in immature rats treated with monosodium glutamate." American Journal of Physiology-Endocrinology and Metabolism 248, no. 1 (January 1, 1985): E126—E131. http://dx.doi.org/10.1152/ajpendo.1985.248.1.e126.
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The number of pituitary gonadotropin-releasing hormone (GnRH) receptors increases during sexual maturation in the rat and probably reflects changes in hypothalamic GnRH secretion. As GnRH is synthesized in various hypothalamic nuclei, including the arcuate nucleas (ARC), we investigated the effects of monosodium glutamate (MSG)-induced lesions of the ARC in the rat. In males and females treated with MSG during the first 10 days of life, GnRH receptor content (GnRH-RC) was unchanged from controls at 10 days but was decreased at 20 and 30 days of age (P less than 0.01). Serum concentrations of luteinizing hormone (LH) were similar in MSG-treated and control males but were significantly lower in 10-day-old females (P less than 0.01). Injections of GnRH (3 micrograms every 8 h on days 18 and 19) restored GnRH-RC to control values in MSG-treated rats. Both MSG and untreated control rats showed similar LH responses to acute injections of GnRH, but responses were attenuated (P less than 0.05) after 2 days pretreatment with GnRH in rats that had received MSG. Ovarian GnRH-RC was similar in both MSG-treated and untreated controls. These data indicate that MSG-induced lesions of the ARC reduce pituitary GnRH-RC in immature rats, and the more marked effects in females suggest a more significant role in the ARC in the control of GnRH secretion during maturation in females. The lack of MSG-induced changes in ovarian GnRH-RC indicates that GnRH from the arcuate nucleus is not responsible for the increase in ovarian GnRH receptors seen during sexual maturation.
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França, L. R., M. O. Suescun, J. R. Miranda, A. Giovambattista, M. Perello, E. Spinedi, and R. S. Calandra. "Testis Structure and Function in a Nongenetic Hyperadipose Rat Model at Prepubertal and Adult Ages." Endocrinology 147, no. 3 (March 1, 2006): 1556–63. http://dx.doi.org/10.1210/en.2005-0640.
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There are few data for hormonal levels and testis structure and function during postnatal development in rats neonatally treated with monosodium l-glutamate (MSG). In our study, newborn male pups were ip injected with MSG (4 mg/g body weight) every 2 d up to 10 d of age and investigated at prepubertal and adult ages. Plasma levels of leptin, LH, FSH, prolactin, testosterone (T), corticosterone, and free T4 (FT4) were measured. MSG rats displayed elevated circulating levels of corticosterone and hyperadiposity/hyperleptinemia, regardless of the age examined; conversely, circulating prolactin levels were not affected. Moreover, prepubertal MSG rats revealed a significant (P < 0.05) reduction in testis weight and the number of Sertoli (SC) and Leydig cells per testis. Leptin plasma levels were severalfold higher (2.41 vs. 8.07; P < 0.05) in prepubertal MSG rats, and these animals displayed plasma LH, FSH, T, and FT4 levels significantly decreased (P < 0.05). Taken together, these data indicate that testis development, as well as SC and Leydig cell proliferation, were disturbed in prepubertal MSG rats. Adult MSG rats also displayed significantly higher leptin plasma levels (7.26 vs. 27.04; P < 0.05) and lower (P < 0.05) LH and FSH plasma levels. However, T and FT4 plasma levels were normal, and no apparent alterations were observed in testis structure of MSG rats. Only the number of SCs per testis was significantly (P < 0.05) reduced in the adult MSG rats. In conclusion, although early installed hyperadipose/hyperleptinemia phenotype was probably responsible for the reproductive axis damages in MSG animals, it remains to be investigated whether this condition is the main factor for hypothalamus-pituitary-gonadal axis dysfunction in MSG rats.
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Pakpahan, Patrick, and Deri Edianto. "Effects of Monosodium Glutamate on the Weight Gain of Experimental Rats." Journal of Endocrinology, Tropical Medicine, and Infectious Disease (JETROMI) 3, no. 3 (August 30, 2021): 102–6. http://dx.doi.org/10.32734/jetromi.v3i3.6721.
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Background: Obesity, as defined by the WHO is an abnormal fat consolidation or excessive fat deposit. Those excessive fat deposits have been known to be the risk factors for cardiovascular diseases. One such additive is known to improve the taste of the food is Monosodium Glutamate (MSG). The purpose of the study is to determine the effects of MSG on weight gain. Methods: This is a simple experimental design with a pretest-posttest design. The study was conducted in the Animal House laboratories of the Faculty of Mathematics and Natural Sciences Universitas Sumatera Utara between October and November of 2019. The sample in this experiment is male Wistar rats aged 10-11 weeks that will be fed with standard animal feed mixed with MSG. There are 2 groups of rats (each group 16 rats), one group 1 (non-MSG), and group 2 (MSG). The rats were fed with animal feed (ad labium) for 31 days. The feed given every single day will be weighed and documented. The subcutaneous fat was taken from the abdominal and axillary regions. Result. After 31 days of treatment, re-weighing of both groups of animals was carried out. The initial weight, final weight, total weight gain, total fat extracted and total feed consumed was not different significant (p>0,05). Conclusion. The feeding of MSG for 31 days, did not have significant effects on weight gain. A longer time is needed for evaluation of MSG effect on weight gain
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Farombi, E. O., and O. O. Onyema. "Monosodium glutamate-induced oxidative damage and genotoxicity in the rat: modulatory role of vitamin C, vitamin E and quercetin." Human & Experimental Toxicology 25, no. 5 (May 2006): 251–59. http://dx.doi.org/10.1191/0960327106ht621oa.
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Monosodium glutamate (MSG) continues to function as a flavor enhancer in West African and Asian diets. The present study examines the modulatory effects of dietary antioxidant vitamin C (VIT C), vitamin E (VIT E) and quercetin on MSG-induced oxidative damage in the liver, kidney and brain of rats. In addition, the effect of these antioxidants on the possible genotoxicity of MSG was investigated in a rat bone marrow micronuclei model. MSG administered intraperitoneally at a dose of 4 mg/g body wt markedly increase malondialdehyde (MDA) formation in the liver, the kidney and brain of rats. Simultaneous administration of VIT C, VIT E and quercetin to MSG-treated rats significantly reduced this increase in MDA induced by MSG. VIT E reduced lipid peroxidation most in the liver followed by VIT C and then quercetin, while VIT C and quercetin showed a greater ability to protect the brain from membrane damage than VIT E. The decreased glutathione (GSH) level elicited by MSG in the three organs corresponded with marked increase in the activity of glutathione-S-transferase (GST). While MSG increased (P B / 0.001) the activities of superoxide dismutase and catalase in the liver, it decreased significantly the activities of these enzymes in the kidney and the brain. The three antioxidants were effective at ameliorating the effects of MSG on GSH levels and the enzymes in the three organs examined. While MSG increased the activity of glucose-6-phosphatase in the liver and kidneys of rats (P B / 0.001), the activity of the enzyme was abysmally low in the brain. There were marked increases in the activities of alanine aminotransferase, aspartate aminotransferase and g-glutamyl transferase in rats treated with MSG. The antioxidants tested protected against MSG-induced liver toxicity significantly. MSG at a dose of 4 mg/g significantly (P B / 0.01) induced the formation of micronucleated polychromatic erythrocytes (MNPCEs). Co-treatment of rats with VIT C and quercetin inhibited the induction of MNPCEs by MSG (P B / 0.001). VIT E failed to protect against MSG-induced genotoxicity. The results indicate that dietary antioxidants have protective potential against oxidative stress induced by MSG and, in addition, suggest that active oxygen species may play an important role in its genotoxicity.
Dissertations / Theses on the topic "MSG rats"
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Soares, Gabriela Moreira. "Alterações no metabolismo lipídico hepático em ratos obesos submetidos à derivação duodeno-jejunal." Universidade Estadual do Oeste do Parana, 2016. http://tede.unioeste.br:8080/tede/handle/tede/667.
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Previous issue date: 2016-01-30Fundação Araucária
Hypothalamic obesity (HyO) is a severe condition without any effective therapy. Bariatric operations appear as an alternative treatment, but the effects of this procedure are controversial. Here, we investigated the effects of duodenal-jejunal bypass (DJB) upon lipid profile and expression of main genes, protein and transcription factors involved in hepatic lipid metabolism pathways in HyO rats. During the first 5 days of life, male newborn Wistar rats received a subcutaneous injection of monosodium glutamate (MSG) [4 g/kg body weight (BW), HyO group]. Control (CTL) group received saline [1.25 g/kg BW]. At 90 days of age, HyO rats were randomly submitted to DJB or sham operations forming HyO DJB and HyO Sham group, respectively. Six months after DJB, obesity parameters, lipids levels, and expression of genes and protein in the liver were verified. HyO Sham rats displayed obesity, hyperinsulinemia, insulin resistance, hypertryglyceridemic and presented higher free fatty acids (FFA) levels and hepatic triglyceride (TG) content. Also, HyO Sham animals enhanced acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN) and stearoyl-CoA desaturase-1 (SCD-1) mRNA levels and ACC and FASN protein in the liver. Carnitine palmitoyltransferase-1a (CPT-1a) and microsomal TG transfer protein (MTTP) were down-regulated in HyO Sham rats. DJB operation normalized serum insulin, TG and FFA levels and hepatic TG content, without changing obesity in these animals. In addition, DJB reduced mRNA levels of liver pyruvate kinase (LPK), ACC, SCD-1, acyl-CoA oxidase (ACO) and carbohydrate response elemento-binding protein (ChREBP). ACC and FASN protein expression were normalized in HyO DJB animals. DJB reduces de-novo lipogenesis and improves hepatic TG content in HyO DJB rats, indicating that this surgery is efficient in the resolution of nonalcoholic fatty liver disease (NAFLD) in HyO.
A obesidade hipotalâmica (OH) é uma condição severa que não apresenta nenhuma terapia eficaz. Cirurgias bariátricas têm surgido como uma alternativa de tratamento, porém, os efeitos deste procedimento são controversos. No presente trabalho, investigamos os efeitos da derivação duodeno-jejunal (DDJ) sobre o perfil lipídico e sobre a expressão gênica de proteínas e fatores de transcrição envolvidos em vias do metabolismo lipídico hepático em ratos com OH. Durante os cinco primeiros dias de vida, ratos Wistar neonatos receberam uma injeção subcutânea de glutamato monossódico (MSG) [4 g/kg de peso corporal, grupo OH]. O grupo controle (CTL) recebeu solução salina [1,25 g/kg de peso corporal]. Aos 90 dias de idade, os ratos OH foram aleatoriamente submetidos à pseudo-cirurgia (PC) ou à DDJ, formando os grupos OH PC e OH DDJ, respectivamente. Seis meses após a DDJ, foram verificados, os parâmetros de obesidade, concentração de lipídios e expressão gênica e proteica no fígado. Ratos OH PC apresentaram obesidade, hiperinsulinemia, resistência à insulina, hipertrigliceridemia, concentrações elevadas de ácidos graxos livres (AGL) e do conteúdo de triglicerídeo (TG) hepático. Também, os animais OH PC tiveram aumento na quantidade de mRNA da acetil-CoA carboxilase (ACC), ácido graxo sintetase (FASN) e estearoil-CoA desaturase-1 (SCD-1) e da expressão proteica da ACC e FASN no fígado. A expressão gênica da carnitina palmitoil-transferase-1a (CPT-1a) e da proteína de transferência de triglicerídeos microssomal (MTTP) foram menores no fígado do grupo OH PC. A cirurgia de DDJ normalizou a concentração de insulina, AGL e TG séricos e o conteúdo de TG hepático, sem alterar a obesidade nesses animais. Além disso, a DDJ reduziu a expressão do mRNA da piruvato quinase hepática (LPK), ACC, SCD-1, acil-CoA oxidase (ACO) e da proteína de ligação do elemento responsivo à carboidratos (ChREBP). A expressão proteica de ACC e FASN foi normalizada em animais OH DDJ. A DDJ reduz a lipogênese de novo e melhora o conteúdo de TG hepático em ratos OH DDJ, indicando que esta cirurgia é eficiente na resolução da doença hepática gordurosa não alcoólica (DHGNA) na OH.
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Costa, Karine Figueredo da. "Avaliação dos tecidos periodontais e aorta abdominal de ratos com obesidade induzida pelo glutamato monossódico e periodontite experimental." Universidade Estadual do Oeste do Parana, 2015. http://tede.unioeste.br:8080/tede/handle/tede/738.
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Previous issue date: 2015-02-24Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Background and Objective: Periodontal disease is a chronic disease that affects a major population part and has been associated with systemic changes. As a result, its relationship with obesity and atherosclerosis, it is a matter of concern for the health system.The aim of this study was to evaluate the behavior of periodontal tissues and abdominal aorta artery in rats with hypothalamic obesity associated with experimental periodontitis. Material and Methods: Twenty-eight male Wistar rats were divided , initially, into 2 groups that were subjected to intradermal injections of 4G/kg of solution of Monosodium glutamate (MSG) and 1,25G/kg/day of saline solution (group CTL)in the cervical region, in the first 5 days of life. At 70 days, the groups were subdivided into 2 another groups, where was induced periodontitis with the ligation placing in 1s lower molars; creating in this way 4 groups: control group without ligation (CTL); control group with ligation (CTL Lig); group MSG without ligation (MSG); group MSG with ligation (MSG Lig). After 100 days the rats were weighed and the naso-anal lenght was measured, so the index of Lee was determined and, then, the animals were sacrificed. Gingival tissue and abdominal aorta samples, as well as the hemi-jaws were withdrawn for immunological, morphological and radiographic analysis. Results: The interleukin-6 concentration in gingival tissue was significant in CTL Lig group, being that the Tumor Necrosis Factor-alpha concentration in the abdominal aorta is higher in groups with experimental periodontitis (p< 0.05). Both the x-ray analysis as the histology showed a lower alveolar bone loss in the MSG Lig, group when compared to the CTL Lig group (p< 0.05). In the abdominal aorta morphometric analysis there was statistically significant 48 difference in the measurement of the artery wall diameter, being the largest diameter observed in the MSG Lig group (p< 0.05). Conclusion: Therefore, this study suggests that the periodontitis in association with the hypothalamic obesity may contribute to the increase of the width of the abdominal aorta walls, as well as the hypothalamic obesity may exert a protective effect on alveolar bone loss.
Objetivo: O objetivo desse trabalho foi avaliar o comportamento de tecidos periodontais e da artéria aorta abdominal em ratos com obesidade hipotalâmica associada a periodontite experimental. A doença periodontal é uma doença crônica que afeta grande parte da população e tem sido associada a alterações sistêmicas. Sendo assim, sua relação com a obesidade e a aterosclerose, é motivo de preocupação para o sistema de saúde. Metodologia: Vinte e oito ratos Wistar foram divididos, inicialmente, em 2 grupos que foram submetidos a injeções intradérmicas na região cervical de 4g/kg/dia de solução de Glutamato Monossódico (grupo MSG) e 1,25g/kg/dia de solução salina (grupo CTL), nos primeiros 5 dias de vida. Aos 70 dias, esse grupos foram subdivididos em outros 2 grupos, onde foi induzida a periodontite com a colocação de ligadura nos 1ºs molares inferiores; originando-se assim 4 grupos: grupo controle sem ligadura (CTL); grupo controle com ligadura (CTL Lig); grupo MSG sem ligadura (MSG); grupo MSG com ligadura (MSG Lig). Aos 100 dias os ratos foram pesados e mensurados o comprimento naso-anal, assim o índice de Lee foi determinado e, então, os animais foram sacrificados. Amostras de tecido gengival e da aorta abdominal, bem como as hemi-mandíbulas foram retiradas para análises imunológicas, morfológicas e radiográficas. Resultados: A concentração de interleucina-6 no tecido gengival foi significante no grupo CTL Lig, sendo a concentração do Fator de Necrose Tumoral alfa na aorta abdominal maior nos grupos com periodontite induzida (p<0.05). Tanto a análise radiográfica quanto a histológica demonstrou uma menor perda óssea alveolar no grupo MSG Lig, quando comparado ao grupo CTL Lig (p<0.05). Na análise morfométrica da aorta abdominal houve diferença estatisticamente significante na mensuração do diâmetro das paredes da artéria, sendo o maior diâmetro observado no grupo MSG Lig (p<0.05). Conclusion: Logo, este estudo sugere que a periodontite em associação com a obesidade hipotalâmica pode contribuir para o aumento da largura das paredes da aorta abdominal, bem como a obesidade hipotalâmica pode exercer um efeito protetor sobre a perda óssea alveolar.
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Caetano, Luiz Carlos. "Avaliação das citocinas inflamatórias em ratos obesos-msg suplementados ou não com taurina." Universidade Estadual do Oeste do Parana, 2013. http://tede.unioeste.br:8080/tede/handle/tede/641.
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Previous issue date: 2013-11-10Among the several organic alterations arising from obesity, chronic inflammation is associated with the balance of cytokines TNF-α, IL-1β, IL-6, IL-2, IFNg, IL-4 and IL-10, and there is evidence the amino acid taurine (Tau) has anti-inflammatory effect. Therefore, this study investigated the inflammatory profile in plasma and retroperitoneal adipose tissue of MSG-obese rats, supplemented or not, with the TAU. Male Wistar rats received subcutaneous injections of MSG (4mg/kg body weight/day) or hyperosmotic saline during the first 5 days of life, composing the control (CON) and MSG groups. After 21 days, half of each group received TAU 2.5% in drinking water, and separated into 04 groups: CON, CON with TAU (CTAU), MSG and MSG with TAU (MTAU). At 120 days of age, the animals were euthanized. The MSG rats showed an increase in Lee Index, retroperitoneal and perigonadal fat pads deposition, insulin and triglycerides plasmatic concentrations and HOMA-IR, when compared to CON animals, showing that the treatment with MSG led to obesity. The TAU supplementation attenuated retroperitoneal fat deposition, as well as TG concentration. The MSG treatment did not alter the expression of JNK and IκBα. However, the supplementation with TAU increased 61% the expression of IkBα in CTAU group compared to the CON and 107% in the MTAU animals compared to the MSG. The expression of TNF-α, IL-1β and IL-6 in the retroperitoneal adipose tissue were similar in the four groups of animals, as well as plasma concentrations of TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 and IL-10. It is possible to conclude that neonatal treatment with MSG does not influence the inflammatory profile of the animals. We also conclude that the TAU increased 61% of IkBα protein expression in the control group and 107% in the MSG-obese animals, without affecting the inflammatory cytokines. Thus we suggest that TAU can exert their anti-inflammatory effects in adipose tissue, via NF-kB
Dentre as várias alterações orgânicas decorrentes da obesidade, está o processo inflamatório crônico associado ao balanço das citocinas TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 e IL-10, e, há evidências de que o aminoácido taurina (TAU) possui efeito anti-inflamatório. Assim, neste trabalho investigamos o perfil inflamatório plasmático e do tecido adiposo retroperitoneal de ratos obesos-MSG, suplementados ou não, com o aminoácido TAU. Ratos Wistar receberam injeções subcutâneas de MSG (4mg/kg de peso corporal/dia) ou salina hiperosmótica, durante os primeiros 5 dias de vida e foram distribuídos nos grupos MSG e CON, respectivamente. Após os 21 dias de vida, metade de cada grupo recebeu 2,5% de TAU na água de beber, sendo separados nos grupos CON, CON + TAU (CTAU), MSG e MSG + TAU (MTAU). Aos 120 dias de vida os animais foram eutanasiados. Ratos MSG apresentaram obesidade acompanhada de hipertrigliceridemia e resistência à insulina (RI). Todavia, não afetou a expressão de IκBα e JNK. A suplementação com TAU aumentou 61% a expressão do IkBα no grupo CTAU em relação ao grupo CON e 107% nos animais MTAU em comparação com os obesos-MSG. As expressões de TNF-α, IL-1β e IL-6 no tecido adiposo retroperitoneal foram semelhantes nos 4 grupos de animais estudados, assim como as concentrações plasmáticas do TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 e IL-10. É possível concluir que o tratamento neonatal com MSG não influencia o perfil inflamatório dos animais. Concluímos também que a TAU aumentou a expressão proteica do IkBα nos animais controle e MSG, sem afetar as citocinas inflamatórias. Desta forma sugerimos que a TAU possa exercer seus efeitos anti-inflamatórios no tecido adiposo, via NF-κB
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Dumont, Dominique. "Contribution à l'étude du contrôle de la sécrétion de l'a-MSH par le lobe intermédiaire de l'hypophyse du rat." Master's thesis, Université Laval, 1985. http://hdl.handle.net/20.500.11794/33652.
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Wong, Chi-wai, and 汪志偉. "Intermedin and its receptor components in the reproductive systems of the rat and the effect of intermedin on uterine contraction." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48521899.
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Intermedin (IMD) is a peptide hormone discovered in 2004 belonging to the calcitonin/calcitonin gene-related peptide superfamily. It signals through a Gprotein coupled receptor by the coupling of a calcitonin receptor-like receptor (CRLR) and one of the receptor activity-modifying proteins (RAMPs) 1-3. Due to its similarity to adrenomedullin in structure and functions, IMD is also known as adrenomedullin 2 (ADM2).
Among members of the superfamily, IMD shares the highest degree of homology with ADM, which is a multifunctional vasodilator ubiquitously expressed in various tissues and organs and has been studied by our group for its reproductive functions. It is hypothesized that IMD may be present in the reproductive systems of the rat and exert some effects on reproductive functions.
The objectives of this study were to investigate the expression of IMD and its receptor components in the male and female reproductive systems of the rat, the changes in expression across the oestrous cycle, and its effect on uterine contraction. The gene expression levels of Imd and its receptor components and peptide levels of IMD were measured by RT-PCR and enzyme immunoassay respectively. The effect of IMD on the uterine contraction was studied by the organ bath technique.
Imd mRNA and IMD levels were detected in the testis, epididymis, ventral prostate, coagulating gland, and seminal vesicle of the male rat and the ovary, oviduct, and uterus of the female rat, suggesting possible roles for IMD in both the male and female reproductive systems. In the male, the Imd mRNA levels were the highest in the seminal vesicle but lowest in the testis and the epididymis and IMD peptide levels were the highest in the coagulating gland but lowest in the epididymis. In the female, the Imd mRNA and IMD peptide levels were the highest in the oviduct and the uterus respectively while both the Imd and IMD levels were the lowest in the ovary.
Imd mRNA and IMD levels displayed cyclic changes in various female reproductive tissues across the oestrous cycle. In the ovary, positive immunostaining was detected in the follicles and corpora lutea with more staining in the latter. The Imd mRNA level was significantly higher at prooestrus than dioestrus while the IMD peptide level was significantly higher at metoestrus than dioestrus. In the oviduct, the Imd mRNA level was the lowest at dioestrus but the IMD peptide level was the highest at dioestrus. Positive immunostaining was observed in the ciliated epithelial cells. Uterine Imd mRNA level was the highest at prooestrus while the IMD level was the highest at dioestrus. IMD was found in the luminal and glandular epithelia.
IMD significantly reduced the uterine contraction amplitude and frequency but not the basal tone. CGRP receptor antagonist hCGRP8-37 and ADM receptor antagonist hADM22-52 partially abolished the inhibitory effect of IMD on uterine contraction while the IMD specific receptor antagonist hIMD17-47 completely blocked the actions. Enzyme inhibitors of NO (L-NAME) and PI3K (Wortmannin) pathways diminished the IMD-mediated effects on uterine contraction while cAMP/PKA blocker KT5720 had no effect.published_or_final_version
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Master of Philosophy
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Paiva, Luis Alberto. "Oxytocin neurone activity and release following administration of melanotan-II in anaesthetised rats." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28948.
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Oxytocin release within the brain modulates several social behaviours in animals and humans. Moreover, low central oxytocin content has been linked to neuropsychiatric disorders, such as anxiety and autism. The exogenous administration of oxytocin has been proposed for therapeutic treatment, but oxytocin does not cross the blood-brain barrier (BBB) in physiologically significant amounts. An alternative approach to oxytocin administration is to stimulate central oxytocin release using melanocortins. Central administration of the naturally occurring melanocortin, α-MSH, has been shown to trigger somatodendritic oxytocin release in vitro. Unfortunately, endogenous melanocortins also do not penetrate the BBB in neuroactive amounts. In this study, I investigated whether systemic administration of synthetic melanocortin receptor 3/4 (MC3/4) agonist, Melanotan-II (MT-II), affects oxytocin neuronal activity and secretion in anaesthetised rats. I hypothesised that systemic administration of MT-II directly (centrally) acts on magnocellular oxytocin neurones to trigger somatodendritic oxytocin release from neurones of the supraoptic nucleus (SON) of the hypothalamus in vivo. Firstly, using double immunohistochemistry against Fos protein, a widely used marker for neural activity, and oxytocin, I showed that intravenous (i.v.; 1 mg/kg), but not intranasal (1 and 30 μg rat), administration of MT-II markedly induced Fos expression in magnocellular oxytocin neurones of the SON and paraventricular nuclei (PVN) of the hypothalamus, and this response was prevented by prior intracerebroventricular (i.c.v.) administration of the melanocortin antagonist, SHU-9119 (1 μg rat). In addition, brain areas receiving peripheral inputs which are involved in the regulation of oxytocin and vasopressin release were also analysed, showing that i.v. MT-II significantly increased Fos expression in the nucleus tractus solitarii (NTS), but not in circumventricular organs of the anteroventral third ventricle (AV3V) region. MT-II-induced Fos in the NTS was not prevented by the i.c.v. melanocortin antagonist. Then, using in vivo electrophysiology, I investigated whether i.v. administration of MT-II affects the electrical activity of SON neurones. Extracellular single-unit recordings from identified magnocellular neurones of the SON showed that MT-II significantly increased the firing rate in oxytocin neurones, however, no significant changes in firing rate were detected in vasopressin neurones. Finally, in vivo oxytocin release experiments showed that i.v. administration of MT-II did not trigger somatodendritic oxytocin release within the SON as measured by microdialysis and subsequent radioimmunoassay. Interestingly, the i.c.v. administration of MT-II (1 μg rat) also failed to trigger oxytocin release within the SON. The analysis of oxytocin content in plasma revealed that the change in oxytocin concentration was significantly greater in i.v. MT-II injected rats compared to vehicle-injected rats. Taken together, these results show that after i.v., but not intranasal, administration of MT-II, the activity of magnocellular neurones of the SON is increased. As previous studies showed that SON oxytocin neurones are inhibited in response to direct application of melanocortin agonists, the actions of i.v. MT-II are likely to be mediated, at least in part, indirectly by activation of inputs from the caudal brainstem.
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Steven, Rory Thomas. "Investigations in MALDI-MSI using a high repetition rate laser." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5392/.
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Within these studies the properties of a high repetition rate (≤ 25,000 Hz) Nd:YVO4 laser were investigated with a view to improving the throughput and quality of information obtained from MALDI MS data collected in continuous raster sampling mode. Initially, the nature of the laser beam profile was investigated and a novel fluorometric method developed for imaging these profiles. Analysis of thin film samples of α-cyano-4-hydroxycinnamic acid (CHCA) and lipid standard phophatidylcholine (PC) 34:1 were carried out. Under most conditions a lower repetition rate and slow stage raster speed were found to be optimal. However, in tissue based investigations repetition rates of 5-10 kHz and faster raster speeds were found to increase the detected ion intensity. Subsequent to this, the use of para-nitroaniline (PNA) as an effective matrix for high-repetition rate laser MALDI MSI applications was investigated and compared to CHCA. PNA was found to provide high quality MSI data, comparable to or better than that obtained with CHCA. The utility of CHCA and PNA were then investigated for the repeat analysis of single tissue sections with a view to increasing the amount of information obtained. Up to five analyses of the same tissue section were demonstrated. Repeat analysis was then applied to the acquisition of both lipid and protein data from a single tissue section using multiple matrices and tissue washing.
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Lubaczeuski, Camila. "Participação do sistema nervoso parassimpático no metabolismo energético e na proliferação celular em ilhotas pancreáticas de ratos obesos-MSG." Universidade Estadual do Oeste do Parana, 2013. http://tede.unioeste.br:8080/tede/handle/tede/627.
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Previous issue date: 2013-08-01The growing number of overweight and obesity has led to an increase in the number of patients with insulin resistance and diabetes mellitus type 2. MSG obese rats were glucose intolerant, insulin resistant and theirs pancreatic islets secrete more insulin in response to glucose. Subdiafragmatic vagotomy changes the response of islets to glucose and improves glucose homeostasis, supporting the hypothesis that an unbalance of autonomic nervous system with increased parasympathetic nervous system (PNS) action but a decreased sympathetic nervous system function. Studies showed that the PNS is also involved in β-cell proliferation. Therefore, we investigated of PNS participation, using a subdiafragmatic vagal denervation, upon pancreatic β-cell function and mass regulation, and the body glucose control disruption in MSG-obese rats. For this, Male Wistar rats received during the first five days of life monosodium glutamate (MSG) or saline. Subdiaphragmatic vagotomy was performed at 30 days of life. At 90 days of age, we verified static insulin secretion, pancreas morphometric, ERK expression in islets, glucose homeostasis and lipidis. The MSG treatment caused obesity at 90 days of life. MSG rats presented lower body weight and nasoanal length, increased Lee index and fat depots, normoglycemia, hyperinsulinemia, dyslipidemia, glucose intolerance and insulin resistance when compared to CTL. Vagotomy performed at 30-days of age prevented obesity, fat deposition in the liver and ameliorated glucose tolerance and insulin sensitivity in adult MVAG rats in relation to MSG rats. Islets from MSG rats secreted more insulin at stimulatory glucose concentrations than CTL islets. Histological analysis showed that pancreatic islets from MSG rats were lower with a reduction in β-cell area without modification in α-cell content when compared with CTL. Also, MSG group presented an increased number of pancreatic islets per mm2, with higher number of islets, which may contributes to the higher islet and β-cell relative mass in the MSG pancreas. These effects were associated with enhanced proliferation in MSG group. The number of MVAG pancreatic islet were less than MSG. Vagotomoy performed at 30-days of age, reduced islet and β-cell area in the pancreas from 90-days old CVAG rats. Finally, the relative islet and β-cell mass in MVAG and CVAG rats was similar to CTL. Here we verified if ERK was involved in β-cell replication in MSG rats, but presented no alteration. We demonstrate for the first time that adult MSG rats showed enhanced pancreatic β-cell proliferation which contributes to the higher islet insulin secretion in response to glucose. The vagus nerve is the main factor involved in such a process, since vagotomy performed at 30 days of age prevented islet morphological alterations in adult MVAG rats. Possibly this increase PNS activity in MSG endocrine pancreas is responsible to hyperinsulinemia that enhanced fat storage, damaged glucose homeostasis and insulin action in MSG obesity.
O crescente número de pessoas com sobrepeso e obesidade tem levado ao aumento no número de pacientes com resistência à insulina (RI) e portadores do Diabetes mellitus tipo 2. Ratos obesos MSG são intolerantes à glicose (Gli), RI e suas ilhotas pancreáticas secretam mais insulina em resposta à concentrações de Gli. A vagotomia subdiafragamática altera a responsividade das ilhotas à Gli e melhora a homeostase glicêmica nestes animais, sugerindo um desbalanço do sistema nervoso autonômico, com aumento do tônus parassimpático e redução do simpático. Estudos demonstram que o sistema nervoso parassimpático (SNP) possui efeito na proliferação das células β-pancreáticas. Desta forma, investigamos a participação do SNP, através da vagotomia subdiafragmática, no metabolismo energético e na proliferação das ilhotas e de células β-pancreáticas de ratos obesos-MSG. Para isto, ratos Wistar machos receberem durante os cinco primeiros dias de vida glutamato monossódico (grupo MSG) ou salina (grupo CTL). A vagotomia subdiafragmática foi realizada aos 30 dias de vida formando os grupos MVAG e CVAG. Aos 90 dias, verificamos a secreção estática de insulina, homeostase glicêmica e lipídica, morfometria do pâncreas e conteúdo proteico da ERK nas ilhotas. Ratos MSG apresentaram redução do peso corporal e comprimento nasoanal, aumento do índice de Lee e acúmulo de gordura, normoglicêmia, hiperinsulinemia, dislipidemia, intolerância à Gli e RI comparados aos CTL. A vagotomia realizada aos 30 dias de vida preveniu obesidade, acúmulo de gordura no fígado e melhorou a tolerância à Gli e a sensibilidade à insulina em ratos MVAG adultos em relação aos ratos MSG. As ilhotas dos animais MSG secretaram mais insulina quando estimulada pela Gli, em relação aos animais CTL. As análises histológicas mostram que as ilhotas pancreáticas dos animais MSG são menores com redução da área das células β sem alteração nas células α em relação aos CTL. O grupo MSG apresenta um aumento do número das ilhotas por mm2, que pode estar contribuindo com o aumento da massa relativa das ilhotas e das células β. Esse efeito está associado ao aumento da proliferação no grupo MSG. O número de ilhotas foi menor nos MVAG em relação aos MSG. A vagotomia realizada aos 30 dias de vida reduziu a área das ilhotas e das células β aos 90 dias de vida nos animais CVAG. Finalmente, a massa relativa das ilhotas e da células β no MVAG e CVAG foram similares ao CTL. Verificamos se a ERK estava envolvida na proliferação das células β nos ratos MSG, porém não apresentaram alterações desta proteína. Pela primeira vez demonstramos que ratos MSG apresentam aumento da proliferação das células β que contribui com o aumento da secreção de insulina em resposta à Gli. O nervo vago é o principal fator envolvido neste processo, visto que a vagotomia realizada aos 30 dias de vida preveniu as alterações morfológicas das ilhotas nos ratos MVAG adultos.
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Mullen, William. "Investigation of the fate of dietary flavonols in humans and rats using HPLC-MS2 techniques." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/612/.
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There is a growing evidence of the potential health benefits of a diet rich in fruits and vegetables. National nutritional guidelines advise the consumption of at least five portions (400 g ) of these foods per day with the goal being a reduction in the levels of coronary heart disease (CHD) strokes and certain cancers. The beneficial properties of fruit and vegetables may be ascribed, in part to the presence of antioxidants and recent attention in this regard has focused on phenolic and polyphenolic compounds. These compounds are present in a wide variety of commonly consumed foods and beverages. Onions are a rich source of the polyphenolic flavonol quercetin-4′-glucoside. For this compound to have some health effects it must be absorbed and reach target organs in a concentration and form where they can exert an effect. To-date interest has focussed on the levels of the intact quercetin aglycone circulating in plasma and excreted in urine. However, it is now known that quercetin does not circulate in the plasma as the parent compound or the aglycone. However, at the outset of this project, the exact form(s) and concentration of metabolites circulating in plasma were unknown. The need to know what compounds are actually circulating, and at what concentration, is important if in vitro studies are to be made into the mechanisms by which quercetin could, potentially, exert a health benefit. The reasons why these issues have not been addressed are due to a number of factors. The main methodology used in studies into absorption, distribution, metabolism and excretion or (A.D.M.E) as it is know in the drug industry, is by use of chromatography coupled to various detection systems. This can range from a simple isocratic single pump linked to a single wavelength absorbance detector, to a gradient pumping system with an autoinjector linked in series to a diode array absorbance detector and mass spectrometer. The latter instruments, although initially expensive are now becoming more affordable. The original methodology used to determine the level of quercetin in plasma involved hydrolysis of the quercetin conjugates back to the aglycone. The information, which is lost by using this hydrolysis method, is vital if we are to gain a better understanding of the A.D.M.E process. There have been a large number of feeding studies carried out using onions or the flavonol contained in them. However, very little additional information was gained after the initial investigations. The objectives of the studies presented in this thesis were to develop methodology to identify and quantify the major metabolites of quercetin in man after ingestion of onions. This would initially require the use of radiolabelled [2-14C]quercetin-4´-glucoside fed to rats to facilitate the development of the method. Having successfully developed methods that would work both in rats and in man, it was of great interest to establish the fate of the complete dose of [2-14C]quercetin-4´-glucoside in rats. In Chapter 2 radiolabelled quercetin-4´-glucoside was used as a tracer to follow the metabolism of the compound as it was acted on by the digestive system of the rat. After 1 h 93% of the ingested dose was recovered in the gastrointestinal tract (GIT). Analysis using HPLC with a photodiode array (PDA) detector in series with a radioactivity monitor connected to an electrospray ion trap mass spectrometer facilitated the separation, quantification and partial identification of 18 out of 19 metabolites. The 1 h sample was part of a larger study that investigated the fate of the radiolabelled compounds up to 5 h after dosing. The latter samples formed part of another study not reported on in this thesis. Having developed the methodology, using the radiolabelled compound, it was then applied to a feed of onions to healthy human volunteers to determine if metabolite detection, identification and quantification could be carried out without the use of the radioactive tracer. In Chapter 3 plasma samples collected 1 h after a feed of onions and urine collection from 0-4 h post feed were used to test if the method could be transferred to a non labelled assay. A total of 22 metabolites plus the parent compound were identified. The metabolic profile of the plasma and urine showed marked differences, again pointing to major post absorption metabolism. The successful transfer of the method from the initial radiolabelled study to the onion feed allowed pharmacokinetic data to be obtained from all plasma samples taken over a 24 h period, along with the 0-24 h urine samples. In Chapter 4 it was seen that the metabolites are both rapidly absorbed and excreted, with plasma levels returning almost back to baseline by 6 h. The total excretion in urine accounted for 4.5% of the ingested dose. These results were controversial, as the pioneer of this field had published that the elimination half life of quercetin was of the order of 18 h. The differences between the two methods employed are discussed in Chapters 3 and 4. The fact that only 4.5% could be accounted for in this study, which was in agreement with other studies, leaves the question of what happens to the other 95.5%. It is possible that the potential health benefit attributed to this compound may have nothing to do with the parent compound but could be coming from something in the other 95.5%. Studies using patients who have undergone an ileostomy have been used to provide further information into what happens to the majority of the dose. By collecting the ileal fluid after a flavonol feed the amount of intact compound can be measured in ileal fluid (Hollman et al., 1995b; Walle et al., 2000). This work and some results from a similar trial study are discussed in Chapter 4, with regard to the process of metabolite absorption and formation. The only way to follow the parent compound throughout its passage through the body is by use of a labelled compound. In Chapter 5 a second feed of [2-14C]quercetin-4´-glucoside, which focuses on the overall fate of the compound, has samples collected for up to 72 h. The fate of the dose was monitored both in terms of the level of radioactivity excreted and found in the tissues and also the identity of the radioactive compounds detected in these samples. In Chapter 5 the results from this study and what impact they could have on quercetin’s potential ability to be the compound responsible for the health benefits are discussed.
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Caquineau, Céline. "Interactions between oxytocin and α-MSH in the regulation of male sexual behaviour in rats." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/24143.
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Firstly, changes in peripheral section of oxytocin and α-MSH, and changes in oxytocin and α-MSH neurone activity were studied in male rats during copulation. Intromission increased plasma concentration of both oxytocin and α-MSH and Fos expression in neurones in the SON and in the PVN and in the accurate nucleus was increased, confirming the similarities between oxytocin and α-MSH in their involvement in male sexual behaviour. The putative interaction between oxytocin and α-MSH was then investigated by studying at which central or peripheral level this interaction would occur. Oxytocin antagonist iv-injection had no effect on the increase of oxytocin and α-MSH secretion during intromission, suggesting that peripheral oxytocin does not regulate peripheral α-MSH secretion. However, oxytocin administered centrally to non-mating conscious rates decreased plasma α-MSH concentration, suggesting that central oxytocin may regulate α-MSH peripheral secretion. These studies therefore support an interaction between central oxytocin and α-MSH. Then, the effects of central α-MSH on oxytocin secretion and neuronal activity were investigated. Central administration of α-MSH induced Fos expression in magnocellular oxytocin neurones in the SON and in the PVN but had no effect on parvocellular oxytocin neurons in the PVN. Α-MSH directly administered onto the SON induced a strong increase in Fos expression in oxytocin neurones in the SON. These studies indicate that α-MSH modulates directly the activity on selected oxytocin neurones and that consequently, αMSH may regulate some specific oxytocin effects and not others. However, central administration of α-MSH decreased oxytocin secretion from the pituitary gland. This illustrates that Fos induction does not necessarily reflect excitation of the neurones. Finally, MC4R antagonist centrally administered reduced the Fos expression induced at intromission in magnocellular oxytocin neurones but had no effect on the Fos expression in the parvocellular neurones.
Books on the topic "MSG rats"
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Bod kyi rgyal rabs don dṅos cuṅ zad gleṅ ba daṅ khrag daṅ mig chuʻi nam zlar rags tsam bltas pa. Delhi: Sherig Parkhang, 1991.
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Gnaʼ boʼi lugs bzaṅ ya rabs srol gtod paʼi deb ther mig yid rna baʼi dgaʼ ston ʼgugs paʼi lcags kyo. Bod: Bod-ljoṅs mi dmaṅs dpe skrun khaṅ, 1991.
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Gu-chu-sum Movement of Tibet (Dharmsāla, India), ed. Raṅ dbaṅ daṅ mig chu: Dus rabs bar maʼi Grwa-bźi btson khaṅ gi źi rgol chab srid kyi yo laṅs chen poʼi dṅos don sñan źu. Dharamsala, H.P: Bod kyi Dgu-bcu-gsum las ʼgul tshogs pa, 2001.
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Gzi-mig Gsang-sngags Bdud-ʼdul Gling-dgon (Sikkim, India), ed. Padmaʼi gnas chen Sbas-yul ʼBras-mo-ljongs kyi shar phyogs Gzi-mig Gsang-sngags Bdud-ʼdul Gling-dgon gyi bla rabs rim byon gyi rnam thar sñiṅ bsdus blo gsar dang ba ʼdren paʼi pho nya. Sikkim: Zimig Sang-ngag Dud-dul Ling Monastery, 2013.
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Castle, David J., Peter F. Buckley, and Fiona P. Gaughran. The metabolic syndrome in schizophrenia. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198811688.003.0003.
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The metabolic syndrome (MS) is a constellation of risk factors including increased waist circumference, high blood pressure, and elevated fasting glucose and triglycerides in conjunction with low levels of high-density lipoprotein. MS is associated with an elevated risk of adverse cardiovascular and other events. The general population rate of MS is increasing, but people with schizophrenia have markedly elevated rates compared to people without a mental illness. Reasons for this excess are complex, but certain antipsychotic agents can exacerbate risk and due care needs to be taken in prescribing such medications, with awareness of longitudinal risk. Treatment needs to be provided following established guidelines, to address aspects of MS should they occur.
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On Interest Rates and Asset Prices in Europe: The Selected Essays of Martin M.G. Fase. Edward Elgar Publishing, 1999.
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Kusmer. DEPRESSION WAR & NEW MIG RATN (Black Communities and Urban Development in America 1720-1990). Articles-Garlan, 1991.
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Kaplan, Tamara B., and Marcelo Matiello. Multiple Sclerosis. Edited by Angela O’Neal. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190609917.003.0026.
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Multiple sclerosis (MS) often affects women of childbearing age. There are many issues to consider when counseling women about their disease and treatment during this time. The Pregnancy in Multiple Sclerosis (PRIMS) study, published in 1998, is the best large-scale prospective study published to date. Based on this trial, and those that followed, it is recognized that the rate of relapse in MS decreases during pregnancy, especially during the third trimester, but there is a significant increase in relapse rate in the first three months postpartum. If relapses do occur during pregnancy, women are often treated with methylprednisolone, but this is generally avoided in the first trimester. Disease-modifying therapies (DMTs) are usually discontinued during preconception, pregnancy, and while breast-feeding. DMTs are classified under different FDA pregnancy categories based on human and animal data. Breast-feeding may influence postpartum relapse rate, but the true effect continues to be debated.
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Rgyal-rtse, Dbaṅ-ʼdud-tshe-riṅ, and Library of Tibetan Works & Archives., eds. Bod kyi rgyal rabs lo rgyus slob gñer ñams źib byed par mkho baʼi lo tshig reʼu mig dgeʼo. [Dharamsala]: Bod kyi dpe mdzod khaṅ, 1996.
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Hebert, Jeffrey R. Exercise and Multiple Sclerosis. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199937837.003.0086.
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The Centers for Disease Control and Prevention has stated that significant health benefits are obtainable for persons with disability who engage in physical activity, recommending 30 to 40 minutes of daily, moderately intense activity. However, persons with MS are frequently physically inactive, with findings of a 6-month activity reduction rate of 6%. This progressive lessoning of physical activity over time is a major contributor to worsening of symptoms and ancillary medical complications such as cardiovascular disease, obesity, and impaired bone health, underpinning the importance of exercise and physical activity by persons with MS. In addition to its effect on endurance and body composition, exercise may also reduce disease activity in MS. A regular exercise program combining exercise and physical activity that is tailored to the patient’s individual condition should be an important part of the plan of care for patients with MS.
Book chapters on the topic "MSG rats"
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Saligram, U., J. E. Moran, and N. Tepley. "MCG Studies in Rats Using Ferrofluids." In Biomag 96, 675–78. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4612-1260-7_165.
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Doyle, D. John. "Mcg/Kg/Min Infusion Rate Finder (IRF)." In Computer Programs in Clinical and Laboratory Medicine, 177–79. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4612-3576-7_41.
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Keegan, Kevin P., Elizabeth M. Glass, and Folker Meyer. "MG-RAST, a Metagenomics Service for Analysis of Microbial Community Structure and Function." In Microbial Environmental Genomics (MEG), 207–33. New York, NY: Springer New York, 2016. http://dx.doi.org/10.1007/978-1-4939-3369-3_13.
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Serieux, John. "Managing the Exchange Rate Consequences of an MDG-Related Scale-Up in HIV/AIDS Financing." In Economic Alternatives for Growth, Employment and Poverty Reduction, 137–59. London: Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230250635_8.
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Marmolejo-Rebellón, Luis Fernando, Edgar Ricardo Oviedo-Ocaña, and Patricia Torres-Lozada. "Organic Waste Composting at Versalles: An Alternative That Contributes to the Economic, Social and Environmental Well-Being of Stakeholders." In Organic Waste Composting through Nexus Thinking, 147–64. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-36283-6_7.
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AbstractComposting is one of the most widely used technologies for the recovery and use of organic waste from municipal solid waste (MSW); however, its implementation in some developing countries has mostly been ineffective. This chapter documents the experience of the composting of municipal organic waste in the urban area of the municipality of Versalles, Valle del Cauca, Colombia. Within the locality, composting of organic waste occurs at an MSW management plant (SWMP), after being separated at the source and selectively collected. The information presented was generated through collaborative research projects, conducted with the cooperation of Camino Verde APC (a community-based organisation providing sanitation services) and Universidad del Valle (Cali, Colombia). The evaluations undertaken show that (i) within the locality, high rates of separation, at the source, in conjunction with selective collection and efficient waste sorting and classification processes in the SWMP, have significantly facilitated the composting process; (ii) the incorporation of locally available amendment or bulking materials (e.g. star grass and cane bagasse) improves the physicochemical quality of the processed organic waste and favours development (i.e. a reduction in process time), leading to an improvement in product quality; (iii) the operation, maintenance and monitoring of the composting process can be carried out by previously trained local human talent; and (iv) revenues from the sale of the final product (compost) are not sufficient to cover the operating costs of the composting process. Despite this current lack of financial viability, the application of technology entails environmental benefits (e.g. a reduction in the generation of greenhouse gases) and social benefits (e.g. employment opportunities), which, given the conditions in the municipality studied, highlight the relevance of this technological option.
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Téot, Luc. "Clinical Case: Earlobe Keloid." In Textbook on Scar Management, 523–26. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44766-3_61.
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AbstractEarlobe keloid is encountered in young adults with different etiologies, with some of them occurring spontaneously and others being secondary to earlobe piercing. In both sexes, the lesions may be limited to the fold or the external canthus or embed the posterior part of the ear. The rate of recurrence is higher than 80% when surgical excision is realized alone and associations of procedures are proposed. They may vary between authors, with some of them proposing excision and radiotherapy and others preferring excision supplemented by postoperative injections of corticosteroids, cryotherapy being also proposed as well as YAG lasers. In this clinical case, 5-FU 50 mg/mL injections were administered every 3 weeks before surgical excision. The patient was followed every month till the 14th month postoperation. The result was good with no recurrence.
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Ogawa, Rei. "Long-Pulsed 1064 nm Nd:YAG Laser Treatment for Keloids and Hypertrophic Scars." In Textbook on Scar Management, 271–78. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44766-3_32.
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AbstractThere are many therapeutic options for keloids and hypertrophic scars, including surgery, radiation, corticosteroids, 5-fluorouracil, cryotherapy, laser therapy, anti-allergy agents, anti-inflammatory agents, bleaching creams, and make-up therapies. In terms of laser therapy, we have used long-pulsed 1064 nm Nd:YAG laser to treat keloids and hypertrophic scars. This laser was developed for the treatment of vascular diseases, including inflammatory scars that exhibit neovascularization. The depth that is reached is determined by the spot size, the laser power, and the fluence: the larger the spot size, power, or fluence, the deeper the laser beam penetrates. The laser should generally be applied to the skin surface with the following standard treatment settings: a spot diameter of 5 mm, an energy density of 75 J/cm2, an exposure time per pulse of 25 ms, and a repetition rate of 2 Hz.
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Szturz, Petr, and Jan B. Vermorken. "High-Dose Three-Weekly or Low-Dose Weekly Cisplatin during Radiation, What to Prefer?" In Critical Issues in Head and Neck Oncology, 139–53. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63234-2_10.
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AbstractIn locally advanced squamous cell carcinoma of the head and neck, adding three cycles of high-dose (100 mg/m2) cisplatin every three weeks to definitive or adjuvant radiotherapy can significantly improve locoregional control and survival. One of the major drawbacks is severe acute toxicity with about 40% of patients developing mucositis, up to one fourth suffering from dysphagia, and at least 20% having bone marrow suppression. Late toxicity has been under- and sometimes mis-reported and may even be responsible for an increase in non-cancer-related deaths in long-term survivors. Moreover, efficacy outcomes are still not satisfactory with 5-year overall survival rates ranging between 40% and 50%, excluding the growing minority of human papillomavirus-related oropharyngeal cancer cases with a markedly better prognosis. Consequently, alternative regimens have gained attention with the aim to reduce toxicity, improve adherence, and maintain adequate anti-tumour activity. Low-dose (usually 40 mg/m2) cisplatin given in weekly intervals emerged as the preferred alternative to the standard, high-dose regimen. But do we have enough evidence to support this approach and which patients might become suitable candidates? While the use of high-dose cisplatin is supported by the results of four large trials randomizing altogether 1539 patients between conventionally fractionated chemoradiation and radiotherapy alone, there are only three small, similarly designed but possibly biased studies favouring a weekly regimen. In addition, two other trials randomly assigning patients to receive either high-dose or low-dose cisplatin, provided evidence against routine administration of the latter schedule. Therefore, although weekly cisplatin may enhance short-term tolerance in terms of gastro-intestinal, hepatic, hearing, renal, and haematological side effects, it cannot be excluded that this improvement comes at the price of compromised survival with no benefit in late adverse events. We acknowledge that certain clinical scenarios, particularly in the presence of relative contraindications to high-dose cisplatin, may favour a less toxic cisplatin dose and/or administration schedule, among which the low-dose weekly regimen. In this respect, the ever-growing population of elderly patients is in particular benefitting from a careful decision, taking into account the pros and cons of such regimens.
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"Effect of Monosodium Glutamate (MSG) on spatial memory in rats (Rattus norvegicus)." In Advances in Biomolecular Medicine, edited by R. Razali, S. Redjeki, and A. A. Jusuf, 71–74. CRC Press, 2017. http://dx.doi.org/10.1201/9781315208619-16.
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Fardian, Nur, Meutia Maulina, M. Fadhlan La Tabari, and Mardiati. "The Effect of Monosodium Glutamate (Msg) Administration to Pyramidal Cells Necrosis on Cerebral Cortex of Wistar Male Rats (Rattus Norvegicus)." In Proceedings of MICoMS 2017, 187–92. Emerald Publishing Limited, 2018. http://dx.doi.org/10.1108/978-1-78756-793-1-00070.
Full textConference papers on the topic "MSG rats"
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Boulogne, Isabelle, and Evelyne Daubie. "MSGC tests with X-rays." In Instrumentation in elementary particle physics. AIP, 1998. http://dx.doi.org/10.1063/1.55058.
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Noda, Yoshiyuki, Michael Zeitz, Oliver Sawodny, and Kazuhiko Terashima. "Flow rate control based on differential flatness in automatic pouring robot." In Control (MSC). IEEE, 2011. http://dx.doi.org/10.1109/cca.2011.6044508.
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Kuo, Chien-Ting, I.-Iming Chen, Feng-Li Lian, Yi-Chun Lin, and Jong-Hann Jean. "Temporal sampling and spatial coding for rate control of video transmission on mobile cameras." In Control (MSC). IEEE, 2010. http://dx.doi.org/10.1109/cca.2010.5611295.
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Alshahrani, Saeed, and Chris Ayadiuno. "Estimating Formation Tops while Drilling Using Rate of Penetration ROP and Mechanical Specific Energy MSE." In SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206093-ms.
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Abstract Accurate determination of formation tops while drilling is a critical part of exploration geology workflow. Operational decisions on coring, wireline logging, casing, and final well depth largely depend on it. One of the commonly used methods for picking formation tops while drilling is to correlate the rate of penetration (ROP) of the new well to wireline logs from offset wells where there is no logging while drilling (LWD) data. Picking formation tops based on only ROP from a new well can result in picking the wrong formation tops. To improve the workflow and outcome, this paper proposes the combination of ROP and Mechanical Specific Energy (MSE) for estimating formation tops while drilling. MSE is a measure of the energy required to crush or drill through a unit volume of rock. Because MSE is related to rock strength, it can be correlated to changes in lithofacies and formation tops. There are three key steps necessary for utilizing mechanical specific energy to estimate formation tops. First, select the input drilling data relevant to the applicable MSE equation. There are several empirical equations in the literature which can be used for estimating MSE. Input data are ROP, Weight on Bit (WOB), Bit Size (BS), Rotation Per Minute (RPM), and Torque (TORQ) from both the offset wells and the new well. Second, utilize a predetermined empirical equation to estimate MSE. Third, correlate MSE and ROP from the new well to both MSE, ROP, and wireline logs from offset wells (where available) to determine formation tops in the new well. Application of the proposed workflow to two wells show 1) distinct bed boundaries, which agree with formation tops picked using wireline logs; (2) that including MSE increases confidence and reliability of the data and makes it easy to identify the different formation boundaries based on the observed features of both MSE and ROP in the new well; and (3) that MSE variations are sensitive to formation strength, which may indicate rock mechanical changes and formation heterogeneity. This paper presents an alternative method of picking formation tops using MSE and ROP while drilling. The preliminary results based on the two test wells showed over 95% match with those picked using wireline logs of the same new well. As a result, this workflow enhances the ability of geoscientists to correlate subsurface geological features, reduces the uncertainty associated with picking formation tops, casing, and coring depths. Furthermore, it improves the confidence in the result, enhances the quality of operational decisions, and reduces the non-productive time (NPT) and well-cost.
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Austin, Brittany, Hazel Marie, Diana Fagan, Jared Vanasdale, and Stuart Drew. "A Biomechanical Investigation of Collagen, Platelet-Rich Plasma, and Mesenchymal Stromal Cells on the Achilles Tendon in a Rat Model." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-10641.
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Abstract This study aims to biomechanically compare four different treatment methods for repair enhancement in Achilles tendon rupture in rats: collagen, collagen and platelet-rich plasma (PRP), collagen and mesenchymal stromal cells (MSC), and a combination of collagen, platelet-rich plasma and mesenchymal stromal cells (CPM) at one and two week healing periods. This study included ninety Lewis rats weighing approximately 200–300 g. Ten rats were used as donors for MSC and PRP. For the remaining eighty rats, the right leg was completely transected 6 mm proximal to the calcaneus bone, suture repaired, wrapped in CollaTape (CoTa), and then closed. An injection of PRP, MSC, or PRP and MSC was given at the wound site to the applicable groups. After one or two weeks recovery time, the rats were sacrificed and both Achilles tendons were removed. The left tendons were used as virgin tissue controls. It was found that the maximum stress at failure, the total strain energy, the average modulus of elasticity, and the elastic strain energy all increase significantly from one week to two week recovery time. However, there was no statistical difference between treatment groups in any of the mechanical properties.
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Koganti, Ramakrishna, Armando Joaquin, Matthew Zaluzec, and Chris Karas. "Influence of Metal Inert Gas (MIG) Welding Factors Wire Feed Rate and Weld Travel Speed on Aluminum Weld Joint Strength." In ASME 2008 International Manufacturing Science and Engineering Conference collocated with the 3rd JSME/ASME International Conference on Materials and Processing. ASMEDC, 2008. http://dx.doi.org/10.1115/msec_icmp2008-72127.
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The purpose of the study was to understand effects of weld travel speed and wire feed rate in metal inert gas (MIG) welding on the aluminum materials joint strength. Initial experiments indicated a noticeable positive effect of travel speed on weld strength with an over 95% statistical significance. Nonetheless further experimentation at a significantly lower wire feed rate proved the opposite with similar statistical significance. A negative effect of welding travel speed on joint strength was measured at lower wire feed rates. In order to understand the weld travel and wire feed rate on the joint strength, a Design of Experiment (DOE) was conducted. For this experiment, weld system process factors were set constant (wave control, gas flow rate, torch angle, trim and wave type) except for travel speed and wire feed rate. A two-factor two-level full factorial design of experiment (DOE) was conducted in order to understand the effects of these two factors on weld strength. Additional welding at higher wire feed rates were conducted in order to confirmed the trend found. Results showed travel speed effects on joint strength as a result of its direct interaction with wire feed rate. This occurrence can have significant economic implications if proven to be repeatable and will be the subject of this and future MIG welding studies as they relate to aluminum structures.
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Seo, Yutaek, Jakyung Kim, and Daejun Chang. "Challenges for Under-Inhibition Strategies for Offshore Gas Fields With Low Production Rates Using OLGA." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54776.
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This study identifies challenges for under-inhibition strategies for offshore flowlines transporting gas-dominant fluids with low flow rates to determine the optimal concentration of hydrate inhibitor. The offshore gas fields considered in this study contains four wellheads, two manifolds, and one flexible riser. The distance between the offshore platform and the manifold is about 20 km with the maximum water depth of 250 m. The commercial multiphase flow simulation tool, OLGA, is used to simulate the operation conditions of the gas fields. The liquid holdup, temperature-pressure profiles, and the accumulated amounts of MEG (Mono-ethylene Glycol) with the distance along the pipeline are calculated during the steady state operation. The obtained results present that at least 44 wt% of MEG is required to completely avoid the hydrate formation when the shut-in condition of the flowline is assumed to be 3 °C and 90 bar. The production rate of base case is about 200 MMscfd and it may decrease to 40 MMscfd in the end of the design life. The accumulated amounts of MEG in the flowline is increased, mainly due to the increase in the accumulated liquid holdup in the pipeline when the production rate is decreased. The injected MEG aqueous solution from each wellhead which has relatively higher density than gas and condensates is stayed in the low spot of the pipeline due to the slower liquid velocity. This system is evaluated to identify the possibility of hydrate blockage formation. An experiment using high pressure autoclave is performed to validate the effect of under-inhibition system with MEG and the kinetic performance of MEG. The optimal concentration of THI (Thermodynamic Hydrate Inhibitor) considering the accumulated amounts in the flowline is calculated from the simulation and experimental results.
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Sheldon, John W., Francisco Alhanati, and Jared Schoepp. "ESP Mechanical Shaft Seals: Trials and Tribulations of Lab Testing." In SPE Gulf Coast Section Electric Submersible Pumps Symposium. SPE, 2021. http://dx.doi.org/10.2118/204494-ms.
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Abstract Mechanical Shaft Seals (MSSs) are critical sub-components in Electric Submersible Pump (ESP) Seal Chamber Sections (SCSs), as they are the primary barriers used to isolate wellbore fluids from the motor oil. However, several ESP operators have observed relatively high MSS failure rates in certain applications, resulting in significant impacts on overall ESP system reliability and operational costs. In some cases, during teardowns, wellbore fluids were found in the lower chambers of the SCS, without any signs of damage to the MSSs or the bags/bellows in the SCS. Thus, to improve the run-life of ESP systems in their applications, operators identified the need to better understand the main influential factors affecting leakage rates through the MSS, including factors associated with the MSS characteristics and its operational conditions. To accomplish this, a test apparatus was built to allow the testing of MSSs in a wide range of operational conditions. This paper summarizes the technical challenges and key learnings that arose from building and commissioning such a test apparatus, as well as conducting several tests on multiple MSSs of a single design. Through commissioning of the test apparatus and subsequent testing, several limitations of the apparatus were identified and corrected through upgrades. Many of these upgrades were related to ensuring reasonably accurate measurement of the leakage rate through the MSSs, in both directions. Unexpected behaviours of the MSS were also observed during some tests. One example is the interesting phenomenon of reverse-pumping where, under certain conditions, leakage occurs in the opposite direction of the applied differential pressure. Finally, questions arose about the importance of certain aspects of quality control for MSSs and/or SCS assembly procedures. The above effort to build and commission a MSS testing apparatus has resulted in unique insight into shaft seal behaviour and continues to shine light on gaps in the industry understanding of factors affecting leakage through MSSs. It certainly provides evidence that there are many ‘unknown unknowns’ about MSS performance under challenging downhole operating conditions, and that the effort is worth continuing to support better MSS design/selection, and SCS assembly, as part of improving ESP system reliability.
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Seo, Yutaek, Jakyung Kim, Kyuchul Shin, Heemoon Chae, and Minsu Ko. "Optimization of MEG Injection and Regeneration System for Offshore Gas Fields Using Multiphase Simulation and Synergistic Inhibition Strategies." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23705.
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Industry has been relying on the injection of considerable amount of Mono Ethylene Glycol (MEG) for hydrate inhibition in petroleum production systems, especially in offshore gas wells. However current design of MEG injection and regeneration systems is used to be over-sized as it consider the worst operation conditions such as shut-in pressure, ambient seawater temperature, and maximum water production rate. Recently, multiphase simulation tools have been widely used to estimate the temperature and pressure profiles of offshore flowlines for both steady-state and transient operations, which would be useful to better estimate the worst operation conditions of offshore flowlines. Moreover, recent research [1] results on synergistic inhibition suggest that MEG injection rate might be reduced below the required concentration by adding small amount of Kinetic Hydrate Inhibitors (KHI). Here we carried out an experiment to validate the effect of using synergistic inhibition with MEG and KHI on the design of MEG injection and regeneration systems for offshore gas wells. The studied concentration range of MEG is up to 30 wt% and PVCap concentration is between 0.1 and 1.0 wt%. Synthetic natural gas composed of C1 90 mol%, C2 6 mol%, C3 3 mol%, and nC4 1 mol% is used for all experiments. High pressure autoclave system mounted with overhead stirrer is used with constant cooling method. Furthermore, multiphase simulation tool, OLGA, is used to simulate the operation conditions of offshore gas fields. The amount of condensed water and temperature-pressure profiles during extended shut-in period are calculated for 10 km offshore flowlines. The obtained results suggest that the injection rate of MEG can be reduced about 50% by adopting synergistic inhibition and multiphase flow simulation, which would reduce the CAPEX and OPEX for MEG. Moreover the reduced size of MEG regeneration unit would improve weight and space management on platform topside.
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Kuhlman, S., C. Parsons, T. Machrowicz, A. Sergueeva, A. Frerichs, B. Meacham, S. Cheng, and D. Branagan. "3rd Generation AHSS High Strain Rate Tensile Testing." In MS&T17. MS&T17, 2017. http://dx.doi.org/10.7449/2017/mst_2017_525_532.
Full textReports on the topic "MSG rats"
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Hicks, Julie, Laurin Yates, and Jackie Pettway. Mat Sinking Unit supply study : Mississippi River revetment. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41867.
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The Mississippi Valley Division (MVD) has maintained the Mississippi River banks for over 80 years. The Mat Sinking Unit (MSU), built in 1946, was considered state-of-the-art at the time. This system is still in operation today and has placed over 1,000 miles of Articulated Concrete Mats along the Mississippi River from Head of Passes, LA, to Cairo, IL. A new MSU has been designed and is expected to be fully mission capable and operational by the 2023 season, which is expected to increase the productivity from 2,000 squares/day up to 8,000 squares/day with double shifts and optimal conditions. This MSU supply study identifies and optimizes the supply chain logistics for increased production rates from the mat fields to the MSU. The production rates investigated for this effort are 2,000 squares/day, 4,000 squares/day, and 6,000 squares/day. RiskyProject® software, which utilizes a Monte Carlo method to determine a range of durations, manpower, and supplies based on logical sequencing is used for this study. The study identifies several potential supply and demand issues with the increased daily production rates. Distance to casting fields, number of barges, and square availability are the major issues to supply increased placement rates identified by this study.
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Li, Bin, Logan Shannahan, Evan Ma, Kaliatt T. Ramesh, Suveen Mathaudhu, Robert J. Dowding, and James W. McCauley. Deformation Mechanisms and High Strain Rate Properties of Magnesium (Mg) and Mg Alloys. Fort Belvoir, VA: Defense Technical Information Center, August 2012. http://dx.doi.org/10.21236/ada568946.
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G.A. Young, Jr, and J.R. Scully. The Effects of Test Temperature, Temper, and Alloyed Copper on the Hydrogen-Controlled Crack Growth Rate of an Al-Zn-Mg-(Cu) Alloy. Office of Scientific and Technical Information (OSTI), September 2000. http://dx.doi.org/10.2172/821950.
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