Academic literature on the topic 'Excretion system'
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Journal articles on the topic "Excretion system"
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Sizeland, P. C., S. T. Chambers, M. Lever, L. M. Bason, and R. A. Robson. "Short-term response of nonurea organic osmolytes in human kidney to a water load and water deprivation." American Journal of Physiology-Renal Physiology 268, no. 2 (February 1, 1995): F227—F233. http://dx.doi.org/10.1152/ajprenal.1995.268.2.f227.
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The cells of the inner medulla of the mammalian kidney accumulate high concentrations of nonurea organic osmolytes. The organic osmolytes found in the kidney include glycine betaine and sorbitol. This study was designed to measure changes in the urinary excretion of glycine betaine and sorbitol and the plasma concentration of glycine betaine in response to an acute water load (20 ml/kg) or acute water deprivation in young healthy males. In response to a water load the urinary excretion of glycine betaine and sorbitol increased parallel with or shortly after urinary urea excretion. The increase in urinary urea and sorbitol excretions preceded maximum minute volume, whereas peak glycine betaine excretion was closely related to maximum urine minute volume. Subsequently, urea, sorbitol, and glycine betaine excretion rates returned to baseline. In contrast, during water deprivation no change in glycine betaine, sorbitol, and urea urinary excretions occurred during the study period. Plasma glycine betaine concentration was stable during both diuresis and antidiuresis. We conclude that the organic osmolytes glycine betaine and sorbitol are components of a physiological and dynamic system in response to an acute water diuresis.
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Modesti, P. A., I. Cecioni, A. Naldoni, A. Migliorini, and G. G. Neri Serneri. "Relationship of renin-angiotensin system and ET-1 system activation in long-lasting response to postural changes." American Journal of Physiology-Heart and Circulatory Physiology 270, no. 4 (April 1, 1996): H1200—H1206. http://dx.doi.org/10.1152/ajpheart.1996.270.4.h1200.
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The present study was performed in seven healthy subjects (aged 22-35 years) to investigate 1) whether plasma and urinary endothelin-1 (ET-1) are involved in the response to postural changes and 2) the relationship between ET-1 formation and the renin-angiotensin system (RAS). Six hours of standing caused a prompt but very short-lasting increase in plasma ET-1 concentration (59% after 5 min, 12% after 1 h) and a notable and sustained enhancement of urinary ET-1 excretion (from 0.59 +/- 0.10 to 1.43 +/- 0.28 pg/min, or 142%; P < 0.001). Plasma renin activity increased by 169% after 1 h of standing. A parallel contraction of urinary volume (-62%), sodium excretion (-55%), and free water reabsorption (-24%) occurred. The return to the supine position after 6 h of orthostasis caused a reduction to baseline values of the ET-1 urinary excretion and urinary volume within 2 h. Inhibition of angiotensin-converting enzyme blunted, but did not eliminate, the orthostasis-induced increase in ET-1 urinary excretion (100%, P < 0.002) and changes in the renal functions. The present results indicate that renal ET-1 is involved in the hemodynamic long-lasting responses to postural changes and that its increase is partially controlled by RAS and suggest that ET-1 might play a role in the regulation of renal function in humans.
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Knox, FG, and JP Granger. "Control of Sodium Excretion: The Kidney Produces Under Pressure." Physiology 2, no. 1 (February 1, 1987): 26–29. http://dx.doi.org/10.1152/physiologyonline.1987.2.1.26.
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Sodium excretion is controlled by an integration of physical, neural, and hormonal regulatory systems. The major systems involved in retention of sodium include the renin-angiotensin-aldosterone system and the sympathetic nervous system. In response to increased sodium intake, the sodium-retaining systems are inhibited and natriuretic hormones are activated. Pressures and flows within the microcirculation of the kidney, in concert with neural and hormonal systems, are important effector mechanisms that work to regulate sodium excretion.
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Ishikawa, Nobutake, and Yoshihiko Takahashi. "Transfer Assist Robot System for Independence Excretion Support." Proceedings of Conference of Kanto Branch 2003.9 (2003): 135–36. http://dx.doi.org/10.1299/jsmekanto.2003.9.135.
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Dong, J., W. H. Mao, G. P. Zhang, F. B. Wu, and Y. Cai. "Root excretion and plant tolerance to cadmium toxicity - a review." Plant, Soil and Environment 53, No. 5 (January 7, 2008): 193–200. http://dx.doi.org/10.17221/2205-pse.
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Significant quantities of Cd have been added to soils globally due to various anthropogenic activities, posing a serious threat to safe food production and human health. Rhizosphere, as an important interface of soil and plant, plays a significant role in the agro-environmental system. This article presents a review of relationship between root excretion and microorganisms and plant resistance to Cd toxicity and possible mechanisms. Root exudates markedly altered in species and quantity under Cd stress. Root exudates can affect Cd absorption by plants through changing the physical and chemical characteristics of rhizospheres. The influence of root exudates on Cd bioavailability and toxicity may include modifying the rhizosphere pH and Eh, chelating/complexing and depositing with Cd ions, and altering the community construction, the numbers and activities of rhizospheric microbes. In this paper, the methods to reduce the transfer of Cd in soil-plant system by adjusting rhizosphere environment are discussed, and some aspects are also proposed that should be emphasized in the future research work.
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Krag, Aleksander, Flemming Bendtsen, Erling Bjerregaard Pedersen, Niels-Henrik Holstein-Rathlou, and Søren Møller. "Effects of terlipressin on the aquaretic system: evidence of antidiuretic effects." American Journal of Physiology-Renal Physiology 295, no. 5 (November 2008): F1295—F1300. http://dx.doi.org/10.1152/ajprenal.90407.2008.
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The vasopressin analog terlipressin is believed to cause vasoconstriction selectively by V1 receptor stimulation. However, a possible antidiuretic effect by V2 receptor stimulation has never been ruled out. Twenty-two patients with ascites, including seven with refractory ascites, were included. The subjects were studied during a 400 ml/h oral water load before and after infusion of 2 mg of terlipressin (18 patients) or placebo infusion (4 patients). Effects on the V2 receptors were assessed by evaluating aquaporin (AQP)2 excretion, free water clearance (C[Formula: see text]), urine osmolality (Uosm), and fractional distal water excretion (DFeH2O). After terlipressin the excretion of AQP2 increased by 89% [144 ng/mmol creatinine, 95% confidence interval (CI) 73–214 ng/mmol creatinine, P = 0.001]. C[Formula: see text] decreased 1.05 ml/min (from 0.17 to −0.89 ml/min, P = 0.001), and DFeH2O decreased 37% (19 vs. 12; 95% CI 2–11, P = 0.01). Uosm increased by 27% (93 mosmol/kgH2O, 95% CI 23–164 mosmol/kgH2O, P = 0.02). Plasma sodium decreased 1.1 mmol/l ( P < 0.01). An increase in AQP2 excretion and a decrease in C[Formula: see text] and distal water excretion after terlipressin despite water loading is a clear indication of activation of the antidiuretic system (V2 receptor effect).
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Yamada, K., K. Hasunuma, T. Shiina, K. Ito, Y. Tamura, and S. Yoshida. "Inter-relationship between urinary kallikrein-kinins and arginine vasopressin in man." Clinical Science 76, no. 1 (January 1, 1989): 13–18. http://dx.doi.org/10.1042/cs0760013.
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1. Physiological saline solution was infused in nine normal subjects and six patients with central diabetes insipidus (DI). At 120 min after the start of infusion, arginine vasopressin (AVP) was injected intramuscularly. Urine was collected in 30 min fractions before and after AVP administration. 2. The urinary excretions of kallikrein-like activity (KAL-A) (S-2266 hydrolysis activity) and immunoreactive kinins (i-kinins) were significantly lower in patients with DI than in normal subjects before AVP administration, while there were no differences in plasma renin activity, plasma aldosterone concentration, creatinine clearance and blood pressure between the two groups, except for a marked water diuresis in patients with DI. The urinary excretion of KAL-A and i-kinins correlated positively with the urinary excretion of AVP. 3. AVP administration increased both plasma AVP and urinary excretion of AVP to similar levels in both groups. As a result, urine volume decreased to a greater degree in patients with DI than in normal subjects. In contrast, the urinary excretions of KAL-A and i-kinins were increased by AVP administration, with a greater response in normal subjects than in the patients with DI. 4. After overnight fasting, acute water loading was carried out orally for 15 min in six normal subjects. At 30 min plasma AVP was suppressed by water loading to almost the basal level found in patients with DI. Urinary excretions of KAL-A and i-kinins in the first 30 min fraction after loading were also suppressed to the basal level in patients with DI. Later, the urinary excretion of KAL-A increased together with the increase in urine flow. Urine volume and free water clearance markedly increased except in the first 30 min fraction, compared with the control period. 5. Thus it is suggested that AVP is one of the factors regulating the renal kallikrein-kinin system in man, although it seems likely that urine flow is still a major factor in urinary kallikrein-kinin excretion.
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Wang, Y., C. Pasparakis, and M. Grosell. "Role of the cardiovascular system in ammonia excretion in early life stages of zebrafish (Danio rerio)." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 321, no. 3 (September 1, 2021): R377—R384. http://dx.doi.org/10.1152/ajpregu.00284.2020.
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The purpose of this study was to investigate if the cardiovascular system is important for ammonia excretion in the early life stages of zebrafish. Morpholino knockdowns of cardiac troponin T (TNNT2) or vascular endothelial growth factor A (VEGFA) provided morphants with nonfunctional circulation. At the embryonic stage [30–36 h postfertilization (hpf)], ammonia excretion was not constrained by a lack of cardiovascular function. At 2 days postfertilization (dpf) and 4 dpf, morpholino knockdowns of TNNT2 or VEGFA significantly reduced ammonia excretion in all morphants. Expression of rhag, rhbg, and rhcgb showed no significant changes but the mRNA levels of the urea transporter ( ut) were upregulated in the 4 dpf morphants. Taken together, rhag, rhbg, rhcgb, and ut gene expression and an unchanged tissue ammonia concentration but an increased tissue urea concentration, suggest that impaired ammonia excretion led to increased urea synthesis. However, in larvae anesthetized with tricaine or clove oil, ammonia excretion was not reduced in the 4 dpf morphants compared with controls. Furthermore, oxygen consumption was reduced in morphants regardless of anesthesia. These results suggest that cardiovascular function is not directly involved in ammonia excretion, but rather reduced activity and external convection may explain reduced ammonia excretion and compensatory urea accumulation in morphants with reduced cardiovascular function.
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Solá, Javier, Jordi Camps, Vicente Arroyo, Francisco Guarner, Joan Gaya, Francisca Rivera, and Joan Rodes. "Longitudinal study of renal prostaglandin excretion in cirrhotic rats: Relationship with the renin–aldosterone system." Clinical Science 75, no. 3 (September 1, 1988): 263–69. http://dx.doi.org/10.1042/cs0750263.
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1. A cross-sectional study (protocol A) was performed in 19 rats with cirrhosis, induced by carbon tetrachloride (CCl4), and ascites and in 10 control animals to assess renal prostaglandin (PG) excretion in experimental cirrhosis. In an additional group of animals, including nine rats chronically exposed to CCl4 (CCl4 rats) and six control rats, a longitudinal study (protocol B) was performed to investigate the temporal relationship between changes in renal PG excretion, the renin—aldosterone system and renal function. 2. Urinary PG excretion was assessed by specific radioimmunoassay of PGE2, PGF2α, 6-keto-PGF1α and thromboxane (TX) B2 after extraction with octadecyl silica cartridges and h.p.l.c. purification. Recoveries for each prostanoid (61 ± 8% for PGE2, 64 ± 12% for PGF2α, 65 ±11% for 6-keto-PGF1α and 66 ±17% for TXB2) were determined in every sample by adding tritiated standards, and the final values were corrected according to the individual recoveries. 3. Cirrhotic rats with ascites in protocol A showed a significantly higher plasma renin and aldosterone concentrations and urinary excretion of 6-keto-PGF1α and TXB2 than did control animals. Urinary excretion of PGE2 and PGF2α, however, was significantly reduced in cirrhotic animals as compared with controls. 4. In CCl4 rats included in protocol B, there was a close chronological relationship between the activation of the renin-aldosterone system, as estimated by urinary aldosterone excretion, the onset of sodium retention and the increase in urinary excretion of 6-keto-PGF1α and TXB2. The urinary excretion of PGE2 and PGF2α in CCl4 rats was reduced throughout the study. 5. These results suggest that in rats with CCl4-induced cirrhosis, the increased renal production of prostacyclin and TXA2 is a consequence of the stimulation of endogenous vasoconstrictor systems. The impaired urinary excretion of PGE2 and PGF2α in CCl4 rats may be secondary to an inhibitory effect of CCl4 on PG synthesis in the renal tubules.
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Calunga, José Luis, Zullyt B. Zamora, Aluet Borrego, Sarahí del Río, Ernesto Barber, Silvia Menéndez, Frank Hernández, Teresita Montero, and Dunia Taboada. "Ozone Therapy on Rats Submitted to Subtotal Nephrectomy: Role of Antioxidant System." Mediators of Inflammation 2005, no. 4 (2005): 221–27. http://dx.doi.org/10.1155/mi.2005.221.
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Chronic renal failure (CRF) represents a world health problem. Ozone increases the endogenous antioxidant defense system, preserving the cell redox state. The aim of this study is to evaluate the effect of ozone/oxygen mixture in the renal function, morphology, and biochemical parameters, in an experimental model of CRF (subtotal nephrectomy). Ozone/oxygen mixture was applied daily, by rectal insufflation (0.5mg/kg) for 15 sessions after the nephrectomy. Renal function was evaluated, as well as different biochemical parameters, at the beginning and at the end of the study (10 weeks). Renal plasmatic flow (RPF), glomerular filtration rate (GFR), the urine excretion index, and the sodium and potassium excretions (as a measurement of tubular function) in the ozone group were similar to those in Sham group. Nevertheless, nephrectomized rats without ozone (positive control group) showed the lowest RPF, GFR, and urine excretion figures, as well as tubular function. Animals treated with ozone showed systolic arterial pressure (SAP) figures lower than those in the positive control group, but higher values compared to Sham group. Serum creatinine values and protein excretion in 24 hours in the ozone group were decreased compared with nephrectomized rats, but were still higher than normal values. Histological study demonstrated that animals treated with ozone showed less number of lesions in comparison with nephrectomized rats. Thiobarbituric acid reactive substances were significantly increased in nephrectomized and ozone-treated nephrectomized rats in comparison with Sham group. In the positive control group, superoxide dismutase (SOD) and catalase (CAT) showed the lowest figures in comparison with the other groups. However, ozone/oxygen mixture induced a significant stimulation in the enzymatic activity of CAT, SOD, and glutathione peroxidase, as well as reduced glutathione in relation with Sham and positive control groups. In this animal model of CRF, ozone rectal administrations produced a delay in the advance of the disease, protecting the kidneys against vascular, hemorheological, and oxidative mechanisms. This behavior suggests ozone therapy has a protective effect on renal tissue by downregulation of the oxidative stress shown in CRF.
Dissertations / Theses on the topic "Excretion system"
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Prasad, Robin. "Development of a computer simulation of the respiratory system to determine the effect of post-inspiratory braking on carbon dioxide excretion." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20296.
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Post-inspiratory braking is the activation of inspiratory muscles during expiration. Although not energetically optimal, it exists for currently unexplained reasons. It has been postulated that post-inspiratory braking exists in order to maintain arterial CO2 content in a tightly regulated band. A computer simulation of the respiratory system incorporating respiratory control, respiratory mechanics, and gas exchange dynamics was developed in order to evaluate the relationship of post-inspiratory braking to arterial CO 2 content. The simulation was driven with pressure signals having varying amounts of post-inspiratory braking. No significant effect upon arterial CO 2 content was found. This suggests that post-inspiratory braking does not exist for the purposes of increasing CO2 exchange in the lungs.
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Prasad, Robin. "Development of a computer simulation of the respiratory system to determine the effect of post-inspiratory braking on carbon dioxide excretion." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0022/MQ50652.pdf.
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O'Donnell, Mark John. "The kidney in diabetes mellitus : urinary transfer in excretion, hypertension, the Renin-Angiotensin-Aldosterone system, and the role of angiotensin converting enzyme inhibitors in therapy." Thesis, University of Birmingham, 1993. http://etheses.bham.ac.uk//id/eprint/37/.
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Patients with diabetic renal disease develop elevated urinary albumin excretion rates [AER] and hypertension. Preliminary data from several groups suggest that diabetic patients handle transferrin, a protein similar in size and weight, in a different fashion from albumin. In the first part of this thesis I report the results of clinical studies of urinary transferrin excretion [TER] in diabetes mellitus. More than 80% type 1 [insulin dependent] diabetic patients have increased TER but less than 40% have increased AER. TER may be provoked by exercise in uncomplicated type 1 diabetes and the rise is proportionally far greater than that for AER. Newly diagnosed type 2 [non-insulin dependent] diabetic subjects have increased TER which falls with improved glycaemic control. Interventional studies with lisinopril, an angiotensin converting enzyme [ACE] inhibitor, in microalbuminuric and macroalbuminuric diabetic subjects show a reduction in TER independent of reduction in blood pressure. Data are presented suggesting a role for altered renal tubular function in TER in diabetes. The second part of the thesis examines the role of the system in the hypertension of diabetic renal disease. Patients with elevated AER have increased resting plasma renin activity. Those with uncomplicated diabetes show an exaggerated blood pressure reponse to exercise. ACE inhibition reduces blood pressure in hypertensive patients and AER in both hypertensive and normotensive patients.
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Engström, Mathias, Olle Pontén, Carlsson Philip, Nadeen Bahnam, Ella Strömberg, and Oskar Westlin. "Antibiotic free and optimised protein production using Escherichia coli." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-352528.
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Affibody® molecules are small therapeutic proteins which mimics antibody functionality. This is a report of several methods for increasing productivity and yield in recombinant production of Affibody® molecules. This literature study shows several steps in the production line which can be optimised, several novel methods for cultivating and harvesting cells and purication of proteins. There is also a section about validation of therapeutic protein production according to The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) are presented.
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Nennich, Tamilee Dawn. "Characterization of manure excretion and environmental impacts of nutrient management in dairy production systems." Online access for everyone, 2004. http://www.dissertations.wsu.edu/Dissertations/Fall2004/T%5FNennich%5F112204.pdf.
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Rached, Paula Abi [UNESP]. "Dacriocistografia em cães com o emprego da ressonância magnética (DCG-RM) e da tomografia computadorizada (DCG-TC)." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/101131.
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Deutscher Akademischer Austauschdienst (DAAD)
A dacriocistografia convencional (DCG) é a técnica de imagem mais utilizada para a avaliação do sistema lacrimal excretor. Recentemente, DCG por ressonância magnética (DCG-RM) e por tomografia computadorizada (DCG-TC) têm sido empregadas em pacientes humanos. No entanto, em cães, os relatos de investigações sobre estas técnicas são escassos. Os objetivos, com este estudo, foram: o desenvolvimento de protocolos de RM e TC; a comparação destas técnicas para avaliação do sistema lacrimal excretar; a avaliação biométrica do ducto nasolacrimal e a apresentação da utilidade de ferramentas de reconstrução tridimensional para a visibilização do sistema lacrimal excretor em cães. Material e Métodos: DCG-RM e DCG-CT foram realizadas bilateralmente em 32 cadáveres de cães. Após canulado, o canalículo superior foi preenchido com meio de contraste (contraste iodado puro e gadolinio 1:200, para CT e RM respectivamente). Imagens transversais e tridimensionais de TC foram obtidas utilizando-se cortes de 0,8mm e 2mm de espessura. O protocolo de RM incluiu as sequências T1W/3D/FFE, T1WfTSE e PDW/TSE. Em ambas as técnicas, foram testadas as orientações perpendicular e obliqua dos cortes. Os diâmetros transversais e longitidinais e o comprimento dos ductos nasolacrimais de 23 cães foram mensurados bilateralmente. Resultados: no exame de DCG-TC, todos os componentes foram visibilizados de modo satisfatório na grande maioria dos animais. O exame de DCG-RM apresentou tempo de varredura mais longo, obtendo-se melhores resultados com a seqüência T1W/3D/FFE. As médias dos diâmetros transversais para os grupos de peso corporal 1, 2 e 3 nas três regiões avaliadas variaram entre 1,07mm e 1,09mm. As médias dos diâmetros longitudinais para as classes 1, 2 e 3 nas três regiões...
Conventional radiographic cannulation dacryocystography is the most commonly used technique for evaluallon of the nasolacrimal system. Recently, MR-DCG and CT¬DCG have been extensively employed in humans patients. Systemafic investigations of these techniques in dogs are not frequently observed in medicai literature. The objectives of this study are: 1, development of MR-DCG and CT-DCG protocols and the comparison between these techniques for the evaluation of the nasolacrimal system in dogs and 2, biometric evaluation of the nasolacrimal duct and to test the usefulness of 3D reconstruction techniques for visualization of this system in dogs. Material and Methods: MR-DCG and CT-DCG were bilaterally performed in 32 cadavers of dogs. The superior lacrimal canaliculi was canulated and contrast media injected (Imerone and Omniscan® 1:200, for CT and MR respectively). CT transverse and 3D images were obtained using 0.8 to 2mm-thick slices. MR protocol included transverse images obtained by T1W/3D/FFE, T1WfTSE and PDW/TSE sequences. For both techniques, two sfice orientations were tested: perpendicular and oblique to the hard palate. Transverse and longitudinal diameters and total length of the nasolacrimal ducts of 23 dogs were bilaterally obtained. Results: in CT scans, ali the structures could be well visualized in great majority of the dogs. MR images required longer scan time. Sequence T1W/3D/FFE offered beber results when compared to PDWTTSE and T1WTTSE. The mean longitudinal diameter of the nasolacrimal duct in weight classes 1, 2 and 3 in ali regions ranged between 1,07mm e 1,09mm. The mean transversal diameter of the nasolacrimal duct in weight classes 1, 2 and 3 in ali regions ranged between 1,34mm e 3,31 mm. The mean length of the nasolacrimal duct in weight classes 1, 2 and 3 were respecfively 70mm, 93,55mm... (Complete abstract click electronic access below)
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Felicissimo, Juliane Marques. "Avaliação do potencial da licochalcona a na terapia da esquistossomose in vitro e em modelo murino." Universidade Federal de Juiz de Fora (UFJF), 2014. https://repositorio.ufjf.br/jspui/handle/ufjf/3106.
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Legítima representante do rol de doenças tropicais negligenciadas, a esquistossomose causada pelos trematódeos do gênero Schistosoma spp. constitui uma enfermidade endêmica em 78 países, impondo grandes desafios à saúde das populações afetadas. Atualmente, a ausência de uma vacina eficaz reforça o papel da quimioterapia como o pilar do controle da morbidade e transmissão, a qual permanece restrita e ameaçada pela eminência de cepas resistentes ao praziquantel. Nos últimos anos, esforços vêm sendo empreendidos na tentativa de descobrir novos fármacos esquistossomicidas, com notável contribuição dos produtos naturais. Neste contexto, o flavonóide Licochalcona A - marcador quimiotaxonômico da espécie Glycyrrhiza inflata – que detém atividades biológicas diversas, como anti-inflamatória, antioxidante e antiprotozoária para espécies de Leishmania spp. e Plasmodium spp., demonstrou atividade esquistossomicida promissora em um estudo preliminar, sendo considerado o objeto do presente estudo. Desta forma, a proposta foi avaliar a progressão da esquistossomose mansônica em camundongos Swiss frente ao tratamento com LicoA, além de obter mais informações acerca de sua atividade contra vermes adultos in vitro. Após um período de 24 horas de incubação, a LicoA a partir de 50µM foi capaz de causar o escurecimento do tegumento dos vermes, a perda moderada da motilidade e áreas de intumescimento corporal. Além disso, produziu pontos de retenção do corante resorufin e consequentemente, a descontinuidade na marcação dos principais túbulos e ramos do sistema excretor dos esquistossomos. Este último pode ser a origem dos demais efeitos, contribuindo para o entendimento das potenciais influências da droga sobre receptores e/ou enzimas presentes nos esquistossomos. Além disso, a suposta inibição parcial das SmATPDases pode igualmente contribuir para o insucesso do parasitismo. Nos ensaios in vivo, o esquema de 50mg/Kg em duas doses administrado por via intraperitoneal foi o mais promissor, alcançado uma mediana de 25% da redução da carga parasitária e o maior deslocamento hepático dos vermes. Por outro lado, a droga não induziu alterações no oograma qualitativo ou no peso hepático e esplênico, mostrando relativa inércia sobre a cinética de oviposição. Mais estudos devem ser conduzidos para acumular evidências sobre o efeito esquistossomicida da Licochalcona A, principalmente os que contemplem um maior número de animais e de parâmetros analisados, como por exemplo, o perfil de citocinas e quimiocinas in vivo, além de outras metodologias in vitro e o aprimoramento daquelas que foram aqui empregadas, de modo a fornecer mais detalhes sobre a influência da LicoA em alguns sistemas intrínsecos ao parasito.
Schistosomiasis, one significant neglected tropical disease, is an infection caused by trematode worms of the genus Schistosoma spp. it is endemic in 78 countries, being a major public health challenge. Currently, the absence of an effective vaccine supports the chemotherapy as the mainstay of schistosomiasis control programs. However, the chemotherapy has limitations, such as, the emergence of praziquantel-resistant strains. In recent years, attempts to discover new antischistosomal drugs had remarkable contribution of natural products. In this context, the flavonoid Licochalcona A - chemotaxonomic marker of the specie Glycyrrhiza inflata - has several biological activities such as anti-inflammatory, antioxidant and anti-protozoan against species of Leishmania spp. and Plasmodium spp. Moreover, Licochalcona A showed promising schistosomicidal activity in a preliminary study. Thus, the aim of this study was to evaluate the progression of schistosomiasis in Swiss mice treated with LicoA and it activity against adult worms in vitro. After 24 hour incubation, concentrations from 50μM LicoA caused tegument darkening, moderate loss of motility and areas of swelling body. Moreover, the exposure to the compound produced accumulation of resorufin and hence the discontinuity in the labelling of the main branches and tubules in the excretory system of schistosomes. The latter may be the source of other effects, contributing to the understanding of the potential influence of the drug on receptors and / or enzymes in schistosomes. In addition, the alleged partial inhibition of SmATPDases can also contribute to the failure of parasitism. In vivo tests, the 50 mg/kg schedule of two doses administered intraperitoneally were the most promising reached a median 25% reduction of worm burden and increased hepatic displacement of the worms. Moreover, the drug did not induce changes in the qualitative or oogram liver and spleen weight relative inertia about showing the kinetics of oviposition. Further studies should be conducted to collect evidence on the effect of schistosomicidal Licochalcona A, especially those that consider a larger number of animals and analyzed parameters, such as the profile of in vivo cytokines and chemokines, and other in vitro methods and the improvement of those who were employed here in order to provide more details on the influence of LicoA in some systems intrinsic to the parasite.
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Reger, Michael Kent. "Dietary intake and urinary excretion of phytoestrogens in relation to cancer and cardiovascular disease." Thesis, 2014. http://hdl.handle.net/1805/6053.
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Indiana University-Purdue University Indianapolis (IUPUI)Phytoestrogens that abound in soy products, legumes, and chickpeas can induce biologic responses in animals and humans due to structural similarity to 17β-estradiol. Although experimental studies suggest that phytoestrogen intake may alter the risk of cancer and cardiovascular disease, few epidemiologic studies have investigated this research question. This dissertation investigated the associations of intake of total and individual phytoestrogens and their urinary biomarkers with these chronic conditions using data previously collected from two US national cohort studies (NHANES and PLCO). Utilizing NHANES data with urinary phytoestrogen concentrations and follow-up mortality, Cox proportional hazards regression (HR; 95% CI) were performed to evaluate the association between total cancer, cardiovascular disease, and all-cause mortality and urinary phytoestrogens. After adjustment for confounders, it was found that higher concentrations of lignans were associated with a reduced risk of death from cardiovascular disease (0.48; 0.24-0.97), whereas higher concentrations of isoflavones (2.14; 1.03-4.47) and daidzein (2.05; 1.02-4.11) were associated with an increased risk. A reduction in all-cause mortality was observed for elevated concentrations of lignans (0.65; 0.43-0.96) and enterolactone (0.65; 0.44-0.97). Utilizing PLCO data and dietary phytoestrogens, Cox proportional hazards regression examined the associations between dietary phytoestrogens and the risk of prostate cancer incidence. After adjustment for confounders, a positive association was found between dietary intake of isoflavones (1.58; 1.11-2.24), genistein (1.42; 1.02-1.98), daidzein (1.62; 1.13-2.32), and glycitein (1.53; 1.09-2.15) and the risk of advanced prostate cancer. Conversely, an inverse association existed between dietary intake of genistein and the risk of non-advanced prostate cancer (0.88; 0.78-0.99) and total prostate cancer (0.90; 0.81-1.00). C-reactive protein (CRP) concentration levels rise in response to inflammation and higher levels are a risk factor for some cancers and cardiovascular disease reported in epidemiologic studies. Logistic regression performed on NHANES data evaluated the association between CRP and urinary phytoestrogen concentrations. Higher concentrations of total and individual phytoestrogens were associated with lower concentrations of CRP. In summary, dietary intake of some phytoestrogens significantly modulates prostate cancer risk and cardiovascular disease mortality. It is possible that these associations may be in part mediated through the influence of phytoestrogen intake on circulating levels of C-reactive protein.
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"Amorphous silica based nanomedicine with safe carrier excretion and enhanced drug efficacy." 2014. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1290657.
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With recent development of nanoscience and nanotechnology, a great amount of efforts have been devoted to nanomedicine development. Among various nanomaterials, silica nanoparticle (NP) is generally accepted as non-toxic, and can provide a versatile platform for drug loading. In addition, the surface of the silica NP is hydrophilic, being favorable for cellular uptake. Therefore, it is considered as one of the most promising candidates to serve as carriers for drugs.The present thesis mainly focuses on the design of silica based nanocarrier-drug systems, aiming at achieving safe nanocarrier excretion from the biological system and enhanced drug efficacy, which two are considered as most important issues in nanomedicine development.
To address the safe carrier excretion issue, we have developed a special type of self-decomposable SiO₂-drug composite NPs. By creating a radial concentration gradient of drug in the NP, the drug release occurred simultaneously with the silica carrier decomposition. Such unique characteristic was different from the conventional dense SiO₂-drug NP, in which drug was uniformly distributed and can hardly escape the carrier. We found that the controllable release of the drug was primarily determined by diffusion, which was caused by the radial drug concentration gradient in the NP. Escape of the drug molecules then triggered the silica carrier decomposition, which started from the center of the NP and eventually led to its complete fragmentation. The small size of the final carrier fragments enabled their easy excretion via renal systems.
Apart from the feature of safe carrier excretion, we also found the controlled release of drugs contribute significantly to the drug efficacy enhancement. By loading an anticancer drug doxorubicin (Dox) to the decomposable SiO₂-methylene blue (MB) NPs, we achieved a self-decomposable SiO₂(MB)-Dox nanomedicine. The gradual escape of drug molecules from NPs and their enabled cytosolic release by optical switch, led to not only high but also stable drug concentration in cytosol within a sustained period. This resulted in enhanced drug efficacy, which is especially manifested in multidrug resistant (MDR) cancer cells, due to the fact that the NP-carrier drug can efficiently bypass the efflux mechanisms and increase drug availability. Together with its feature of spontaneous carrier decomposition and safe excretion, this type of nanomedicine’s high drug efficacy highlights its potential for low dose anticancer drug treatment and reduced adverse effect to biological system, holding great promise for clinical translation.
The enhanced drug efficacy by employing the self-decomposable silica nanocarrier is also demonstrated in photodynamic therapy (PDT). The loose and fragmentable features of the self-decomposable SiO₂-photosensitizer (PS) NPs promoted the out-diffusion of the generated ROS, which resulted in a higher efficacy than that of dense SiO₂-PS NPs. On the other hand, we also explored another nanocarrier configuration of Au nanorods decorated SiO₂ NP, with PS drug embedded into dense SiO₂ matrix. A different mechanism of drug efficacy enhancement was presented as the Au’s surface plasmon resonance enhanced the ROS production. Although the drug efficacy of such SiO₂(PS)-Au NPs was similar to that of self-decomposable SiO₂-PS NPs, their potential for clinical applications was limited without the feature of safe carrier excretion.
In summary, the self-decomposable SiO₂ based NP developed is a most promising system to serve as safe and effective carriers for drugs. Together with the known biocompatibility of silica, the feature of controllable drug release and simultaneous carrier decomposition achieved in the self-decomposable SiO₂-drug NPs make it ideal for a wide range of therapeutic applications.
隨著近年來納米科學技術的快速發展，致力於納米藥物的研发也越來越多。在眾多納米材料體系中，二氧化硅納米顆粒因其無毒、易載藥、且易於細胞攝入等特性，被認為是最具前景的藥物載體之一。
本文主要致力於設計以二氧化硅納米顆粒為載體的納米藥物體系，使之同時具備能夠被生物體安全排泄以降低潛在不良影響，并且能夠加強藥效的特性，而這兩方面被認為正是納米藥物發展中最重要的議題。
爲了實現藥物載體安全排泄，我們設計了一種特殊類型可自降解的二氧化硅-藥物複合納米顆粒。通過在納米顆粒中控制形成徑向藥物濃度梯度分佈，我們達到了藥物釋放的同時伴隨二氧化硅載體解體的效果。這一特徵不同於傳統二氧化硅-藥物複合納米顆粒中藥物均勻分佈而難以擴散出載體的情況。我們發現在這種可自降解的二氧化硅-藥物複合納米顆粒中，首先徑向藥物濃度梯度分佈所引起的擴散控制著藥物釋放，而後藥物分子的流失促發二氧化硅載體由內而外的逐步分解，最終全面解體分裂成碎片。這些碎片的小尺度使得它們易於經泌尿系統安全排泄出體外。
除此之外，我們發現這種納米載體的可控藥物釋放特性可以大大提高藥效。通過將抗癌藥阿黴素載入自降解二氧化硅-亞甲藍納米顆粒中，我們得到一種可自降解二氧化硅/亞甲藍-阿黴素(SiO₂(MB)-Dox)複合納米顆粒。藥物分子可以逐漸擴散出納米顆粒，並且在光控開關作用下釋放到細胞胞漿中，使之在胞漿中持續保持穩定高濃度。這樣使得藥效得以加強，尤其是在多藥抗藥性腫瘤細胞中作用尤為明顯，這得益於納米載體藥物可以有效避開藥泵機制并提高藥物利用率。除了它的自發載體分解和安全排泄特性，這種納米藥物的高藥效使得它在低藥量治療和減少不良副作用方面的潛力突出，臨床應用前景廣大。
可自降解二氧化硅納米載體所帶來的的藥效增強亦顯示在光動力學治療法中。可自降解二氧化硅-光敏劑藥物(SiO₂-PS)複合納米顆粒鬆散易分解的結構特性促使其內部產生的活性氧物質易於擴散出藥物載體，這使得它的藥效高於傳統二氧化硅-光敏劑複合納米顆粒。另一方便，我們設計了一種金修飾的二氧化硅納米顆粒載體。它具有另一種不同的藥效增強機制，即利用金納米顆粒表面等離子體共振效應來增強活性氧物質的產生。雖然藥效與可自降解二氧化硅-光敏劑複合納米顆粒相似，但是它無法安全排泄，限制了其在臨床上的應用。
綜上所述，我們發展的可自降解二氧化硅納米顆粒作為一種安全高效的藥物載體顯示出其非常大的應用前景。二氧化硅以其衆所周知的生物相容性，和我們發展的可控藥物釋放及同步載體分解特性，已成為理想的藥物載體并有希望廣泛適用於治療應用。
Zhang, Silu = 基於無定二氧化硅納米顆粒的安全高效納米藥物的研究 / 張思鷺.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2014.
Includes bibliographical references.
Abstracts also in Chinese.
Title from PDF title page (viewed on 12, October, 2016).
Zhang, Silu = Ji yu wu ding er yang hua gui na mi ke li de an quan gao xiao na mi yao wu de yan jiu / Zhang Silu.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
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KOMENDOVÁ, Jana. "Vliv teploty, velikosti a nakrmenosti ryb na spotřebu kyslíku a exkreci amoniaku u keříčkovce červenolemého (Clarias gariepinus)." Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-55381.
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Aims of this thesis were to assesed the impact of feeding, temperature of water and fish size on ammonia excretion and oxygen consumption in Clarias gariepinus in recirculating system. Fish were divided in 8 weight categories from 21 to 2495 g. Experiments were performed under four temperatures: 22°C, 25°C, 28°C and 30°C. Fish were acclimatized, light conditions were: 14 hours of light period and 10 hours of dark period. Feeding was provided fed four times a day. Starved fish were measured. Measurements were held every two hours. Oxygen consumption was measured by multimeter and ammonia excretion using Nessler?s method. Average daily oxygen consumption in fed fish was dependent on temperature and average individual weight of fish, varied from 10.5 to 96.6 mg O2/kg/h and in hungry fish from 4.3 to 61.8 mg O2/kg/h. TAN excretion varied from 0 to 59.9 mg TAN/kg/h in fed fish and from 0 to 60.8 mg TAN/kg/h in hungry fish. Oxygen consumption increased with increasing temperature. Ammonia excretion was very unstable at all temperatures in all weight categories. Fish had higher ammonia excretion in light period of experiment.
Books on the topic "Excretion system"
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Klosterman, Lorrie. The excretory system. Tarrytown, N.Y: Marshall Cavendish Benchmark, 2010.
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B, Silverstein Virginia, and Silverstein Robert A, eds. The excretory system. New York: Twenty-First Century Books, 1994.
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Klosterman, Lorrie. Excretory system. Tarrytown, NY: Marshall Cavendish Benchmark, 2010.
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ill, Ye Luying, ed. Ba ba cong na li lai: Liao jie ren ti de xiao hua xi tong. Hangzhou Shi: Zhejiang ren min mei shu chu ban she, 2016.
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Burton, Derek, and Margaret Burton. Excretion. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198785552.003.0008.
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Excretion is the removal of metabolic wastes such as ammonia, carbon dioxide, ions and water as well as toxic xenobiotics and metals. The process involves the gills, kidney, liver and rectal gland (elasmobranchs and coelacanth). In the liver, amino acids, haemoglobin, steroids and molecules resulting from human activities are transformed to excretable products. The rectal gland excretes ions, notably Na+ and Cl−. The kidney in teleosts has a distinction between an anterior head-kidney containing haematopoietic tissue and endocrine tissue and the posterior region with nephrons (kidney tubules). Fish nephrons generally have a Malphigian corpuscle with a glomerulus but the structure varies between fish taxa and some marine teleosts lack a glomerulus. Control systems for fish excretion are unclear but it is expected that various hormones influence excretory homeostasis.
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Wagner, Carsten A., and Olivier Devuyst. Renal acid–base homeostasis. Edited by Robert Unwin. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199592548.003.0024.
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The kidney is central to acid–base homeostasis. Major processes are reabsorption of filtered bicarbonate, de novo synthesis of bicarbonate from ammoniagenesis, and net excretion of protons. The latter requires buffers such as ammonium, phosphate, citrate and other bases binding protons (so-called titratable acids). The proximal tubule is the major site of bicarbonate reabsorption and only site of ammoniagenesis. The thick ascending limb and the distal convoluted tubule handle ammonia/ammonium and complete bicarbonate reabsorption. The collecting duct system excretes protons and ammonium, but may switch to net bicarbonate secretion. The kidney displays a great plasticity to adapt acid or bicarbonate excretion. Angiotensin II, aldosterone and endothelin are involved in regulating these processes, and they induce morphological changes along the nephron. Inborn and acquired disorders of renal acid–base handling are caused by mutations in acid–base transport proteins or by dysregulation of adaptive mechanisms.
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Dalbeth, Nicola. Epidemiology. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198748311.003.0003.
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The aetiopathogenesis of gout is initiated by urate overproduction and uric acid under-excretion, leading to hyperuricaemia. Foods such as seafood, red meat, beer, and sugar-sweetened beverages contribute to overproduction. Under-excretion is mediated by renal and gut uric acid transporters such as SLC2A9, ABCG2, and URAT1. In hyperurcaemia, there is formation of monosodium urate (MSU) crystals in joints, with acute gouty arthritis mediated by the innate immune system occurring in response to these crystals. Factors such as urate concentration, proteins present in synovial fluid, temperature, and pH control crystal nucleation and growth. Activation of the inflammasome by MSU crystals and production of interleukin-1ß is central to acute gouty arthritis. Advanced gout occurs when there is persistent gouty arthritis and tophus with the tophus being an organized immune tissue response to MSU crystals that involves both innate and adaptive immune cells. Progression through the gout checkpoints (hyperuricaemia, MSU crystal formation, and immune response) is governed by inherited genetic variants, lifetime environmental exposures, and their interaction.
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Kreit, John W. Gas Exchange. Edited by John W. Kreit. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190670085.003.0002.
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Gas Exchange explains how four processes—delivery of oxygen, excretion of carbon dioxide, matching of ventilation and perfusion, and diffusion—allow the respiratory system to maintain normal partial pressures of oxygen (PaO2) and carbon dioxide (PaCO2) in the arterial blood. Partial pressure is important because O2 and CO2 molecules diffuse between alveolar gas and pulmonary capillary blood and between systemic capillary blood and the tissues along their partial pressure gradients, and diffusion continues until the partial pressures are equal. Ventilation is an essential part of gas exchange because it delivers O2, eliminates CO2, and determines ventilation–perfusion ratios. This chapter also explains how and why abnormalities in each of these processes may reduce PaO2, increase PaCO2, or both.
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Bramham, Kate, and Catherine Nelson-Piercy. Pregnancy and renal physiology. Edited by Norbert Lameire and Neil Turner. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199592548.003.0294_update_001.
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Pregnancy is characterized by unique physiological changes within the kidney, resulting in a marked increase in renal blood flow and glomerular filtration, which are associated with successful pregnancy outcomes. Early in normal pregnancy there are increases in plasma volume and cardiac output, but a lowered peripheral resistance leads to average blood pressures being lower. A pregnancy-associated respiratory alkalosis occurs. Protein excretion tends to increase slightly in women without kidney disease. Kidney size is increased, and pelvicalyceal system dilatation is noticeable in most women in the third trimester, right greater than left.
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Daudon, Michel, and Paul Jungers. Cystine stones. Edited by Mark E. De Broe. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199592548.003.0203_update_001.
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Cystinuria, an autosomal recessive disease (estimated at 1:7000 births worldwide), results from the defective reabsorption of cystine and dibasic amino acids (also ornithine, arginine, lysine, COAL) by epithelial cells of renal proximal tubules, leading to an abnormally high urinary excretion of these amino acids. Due to the poor solubility of cystine at the usual urine pH, formation of cystine crystals and stones ensues. Incidence of homozygotes is estimated at 1 in 7000 births worldwide, but is lower in European countries and much higher in populations with frequent consanguinity. Cystine stones represent 1–2% of all stones in adults and 5–8% in paediatric patients, with an equal distribution between males and females.Cystinuria is caused by inactivating mutations in the gene SLC3A1 or SLC7A9, both encoding proteins contributing to the function of the heterodimeric transport system of cystine.Cystine nephrolithiasis may present in infants, most frequently in adolescents or young adults, sometimes later. Cystine calculi are weakly radio-opaque. Stone analysis using infrared spectroscopy (or X-ray diffraction) allows immediate and accurate diagnosis. Urinary amino acid chromatography quantifies urinary cystine excretion, needed to define the therapeutic strategy.Urological treatment of cystine stones currently uses extracorporeal stone wave lithotripsy or flexible ureterorenoscopy with Holmium laser, that is, minimally invasive techniques. However, as cystine stones are highly recurrent, preventive therapy is essential.Medical treatment combines reduced methionine and sodium intake, to lower cystine excretion; hyperdiuresis (> 3 L/day) to reduce cystine concentration; and active alkalinization preferably using potassium citrate (40–80 mEq/day) to increase cystine solubility by rising urine pH up to 7.5–8. If these measures are insufficient to prevent recurrent stone formation, a thiol derivative (D-penicillamine or tiopronin), which converts cystine into a more soluble disulphide, should be added. Close monitoring and adherence of the patient to the therapeutic programme are needed to ensure life-long compliance, the key for successful prevention in the long term.
Book chapters on the topic "Excretion system"
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South, A. "Vascular system, water relations and nitrogenous excretion." In Terrestrial Slugs, 80–96. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2380-8_4.
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Wennmalm, Å. "Metabolism and Excretion of Nitric Oxide in Man: Basal Studies and Clinical Applications." In Mediators in the Cardiovascular System: Regional Ischemia, 129–38. Basel: Birkhäuser Basel, 1995. http://dx.doi.org/10.1007/978-3-0348-7346-8_18.
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Yamaguchi, Osamu, Yutaka Usuda, Kazuhiro Kaneko, Masahide Ohtsuka, and Fukuichiro Okumura. "Automatic Adjustment of Minute Volume by Carbon Dioxide Excretion with Servocontrol System." In Computing and Monitoring in Anesthesia and Intensive Care, 156–57. Tokyo: Springer Japan, 1992. http://dx.doi.org/10.1007/978-4-431-68201-1_42.
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Wu, Yu-Tse, and Tung-Hu Tsai. "Microdialysis in the Hepatobiliary System: Monitoring Drug Metabolism, Hepatobiliary Excretion, and Enterohepatic Circulation." In Applications of Microdialysis in Pharmaceutical Science, 275–94. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118011294.ch8.
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Carey, Robert M., Shetal H. Padia, John J. Gildea, and Susanna R. Keller. "Role of Renal Aminopeptidases and Angiotensin Type-2 (AT2) Receptors in Sodium Excretion and Hypertension." In The Local Cardiac Renin-Angiotensin Aldosterone System, 107–20. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-1-4419-0528-4_11.
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Kurschel, E., U. Metz-Kurschel, N. Niederle, O. Kloke, and C. G. Schmidt. "Detection of Urinary Enzyme Excretion as a Parameter of the Nephrotoxicity of Human Interferon Alpha-2b in Patients with Hairy Cell Leukemia (HCL)." In The Biology of the Interferon System 1986, 349–54. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3543-3_48.
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Pedersen, Michael, Pietro Irrera, Walter Dastrù, Frank G. Zöllner, Kevin M. Bennett, Scott C. Beeman, G. Larry Bretthorst, Joel R. Garbow, and Dario Livio Longo. "Dynamic Contrast Enhancement (DCE) MRI–Derived Renal Perfusion and Filtration: Basic Concepts." In Methods in Molecular Biology, 205–27. New York, NY: Springer US, 2021. http://dx.doi.org/10.1007/978-1-0716-0978-1_12.
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AbstractDynamic contrast-enhanced (DCE) MRI monitors the transit of contrast agents, typically gadolinium chelates, through the intrarenal regions, the renal cortex, the medulla, and the collecting system. In this way, DCE-MRI reveals the renal uptake and excretion of the contrast agent. An optimal DCE-MRI acquisition protocol involves finding a good compromise between whole-kidney coverage (i.e., 3D imaging), spatial and temporal resolution, and contrast resolution. By analyzing the enhancement of the renal tissues as a function of time, one can determine indirect measures of clinically important single-kidney parameters as the renal blood flow, glomerular filtration rate, and intrarenal blood volumes. Gadolinium-containing contrast agents may be nephrotoxic in patients suffering from severe renal dysfunction, but otherwise DCE-MRI is clearly useful for diagnosis of renal functions and for assessing treatment response and posttransplant rejection.Here we introduce the concept of renal DCE-MRI, describe the existing methods, and provide an overview of preclinical DCE-MRI applications to illustrate the utility of this technique to measure renal perfusion and glomerular filtration rate in animal models.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction is complemented by two separate publications describing the experimental procedure and data analysis.
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Eck, Mathilde, Oliver Körner, and M. Haïssam Jijakli. "Nutrient Cycling in Aquaponics Systems." In Aquaponics Food Production Systems, 231–46. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15943-6_9.
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AbstractIn aquaponics, nutrients originate mainly from the fish feed and water inputs in the system. A substantial part of the feed is ingested by the fish and either used for growth and metabolism or excreted as soluble and solid faeces, while the rest of any uneaten feed decays in the tanks. While the soluble excretions are readily available for the plants, the solid faeces need to be mineralised by microorganisms in order for its nutrient content to be available for plant uptake. It is thus more challenging to control the available nutrient concentrations in aquaponics than in hydroponics. Furthermore, many factors, amongst others pH, temperature and light intensity, influence the nutrient availability and plant uptake. Until today, most studies have focused on the nitrogen and phosphorus cycles. However, to ensure good crop yields, it is necessary to provide the plants with sufficient levels of all key nutrients. It is therefore essential to better understand and control nutrient cycles in aquaponics.
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CHAPMAN, R. F. "Structure of the Digestive System." In Regulation: Digestion, Nutrition, Excretion, 165–211. Elsevier, 1985. http://dx.doi.org/10.1016/b978-0-08-030805-0.50010-9.
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BRADLEY, TIMOTHY J. "The Excretory System: Structure and Physiology." In Regulation: Digestion, Nutrition, Excretion, 421–65. Elsevier, 1985. http://dx.doi.org/10.1016/b978-0-08-030805-0.50016-x.
Full textConference papers on the topic "Excretion system"
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Saitoh, Takeshi, Iori Yamada, and Yu Yoshioka. "Excretion Prediction Using Nursing Record System Log Data." In 2018 57th Annual Conference of the Society of Instrument and Control Engineers of Japan (SICE). IEEE, 2018. http://dx.doi.org/10.23919/sice.2018.8492590.
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Balbotkina, Evgeniya, and Taisia Kovaleva. "VEGETATIVE NERVOUS SYSTEM EFFECTS ON KIDNEY SODIUM EXCRETION IN EXCESS NaCl SUPPLY." In XVII INTERNATIONAL INTERDISCIPLINARY CONGRESS NEUROSCIENCE FOR MEDICINE AND PSYCHOLOGY. LCC MAKS Press, 2021. http://dx.doi.org/10.29003/m2049.sudak.ns2021-17/73-74.
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Anggraini, R., A. Razak, and D. H. Putri. "The Development of Constructivism-Based Biology Learning Modules Equipped With Mind Maps on the Material of Excretion and Coordination System for the 11TH Grade Semester 2." In International Conference on Biology, Sciences and Education (ICoBioSE 2019). Paris, France: Atlantis Press, 2020. http://dx.doi.org/10.2991/absr.k.200807.068.
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Taft, David, Amy Chun, Chen Ren, and Manoj Maniar. "Abstract 3534: Proposed pathway of disposition of ON 01910. Na, a novel clinical trial stage anti-cancer agent: Implicaton of Mrp2 in biliary excretion in the isolated perfused rat liver system." In Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-3534.
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Rafeeque, Ameena, and Mohammed Fasihul Alam. "The effect of Renin Angiotensin System Blockers versus Calcium Channel Blockers on Progression towards Hypertensive Chronic Kidney Disease: A comprehensive systematic review based on Randomized Controlled Trials." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0162.
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Background: Decline in estimated Glomerular filtration rate (eGFR) is associated with further progression of chronic kidney disease. Evidence suggests that Renin Angiotensin System blockers (RAS), which can be angiotensin-receptor blockers (ARBs) or Angiotensin converting enzymes Inhibitors (ACEIs), have reno- protective effect, but results are variable. Similarly, effects of Calcium channel blockers (CCBs) are shown to have a role in protecting renal function but differ across studies. Hence, the relative effect of ARBs or ACEIs as well as CCBs, and their administration as monotherapy, remain uncertain. Purpose: To summarize and determine the pooled effect of RAS versus CCBs on progression towards hypertensive CKD amongst diabetic as well as non-diabetic patients with CKD of any stage from I-IV. Data sources: All language studies in PubMed, the Cochrane Library Central, Clinical Registry of unpublishedTrials, WHO, Embase, Scopus, ProQuest, reference lists, and expert contacts up to September 2019. Study selection: This study included all the full text articles that studied diabetic and non-diabetic patients with eGFR ≥ 15 ml/min per 1.73m3 or Urinary albumin excretion levels (UAE) ≤ 300mg/d during RAS based treatment an intervention in direct comparison with CCBs treatment based approach as comparator at baseline and at the end of follow-up. However, pooling of all the included studies using meta-analysis was not feasible due to substantial study heterogeneity and the small number of included studies that are meta-analyzable. So, studies were selected for systematic review, and out of which, all the meta-analyzable studies were quantitatively analyzed on the basis of main outcomes such as (i) Relative risk for CKD progression and (ii) Mean differences in SBP and DBP for both the arms. Doi plot and funnel plot were used for detection of publication bias. Results: Review with seven included trials, and metaanalysis using IVhet model was done on three studies for primary CKD outcome and four studies for secondary BP outcomes. RAS blockers and CCBs did not show any statistically significant differences in terms of its effects on further progression CKD with RR of 0.90 [95% CI 0.69, 1.16]. Moreover, there was no statistically significant difference in BP from baseline to final end points between CCBs and RAS inhibitors with WMD of -2.09 mmHg [95% CI -5.96, 1.79] for mean SBP change and -0.71 mmHg [95% CI -2.16, 0.73] for mean DBP change. Conclusion: Evidence asserts no difference between RAS and CCB concerning the risk of progression for CKD and in terms of mean BP differences. However, the study have its own set of limitations due to which more well designed and well conducted RCTs with robust findings are required to confirm the inferences based on this review.
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Prasetyo, Triastono Imam, Nursasi Handayani, Alifia Rosidatur Zulfa, and Laila Nur Alifah. "Development of learning tools based on pirposal model on respiratory and excretion systems materials." In THE 4TH INTERNATIONAL CONFERENCE ON MATHEMATICS AND SCIENCE EDUCATION (ICoMSE) 2020: Innovative Research in Science and Mathematics Education in The Disruptive Era. AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0043534.
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Egberg, Nils, Krister Gréen, Jan Jacobsson, Ole Vester-gvist, Bjöm Wiman, and Michael Gallimore. "EFFECTS OF PLASMA KALLIKREIN AND BRADYKININ ON FIBRINOLYSIS AND THROMBOXANE PROSTACYKLIN FORMATION STUDIED IN MINIPIGS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644334.
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The effect of plasma kallikrein and bradykinin infusions into pigs on hemodynamic and hemostatic variables have been investigated. Both substances caused a pronounced decrease of the systemic blood pressure. The leucocyte count in periferal blood fell markedly, reaching a minimun within one hour after infusion of either of the substances.Signs that could be interpreted as a progressive disseminated intravascular coagulation with decrease of fibrinogen and platelet count was observed after kallikrein as well as bradykinin infusions. A pronounced increase of the plasma tissue plasminogen activator concentration followed both plasma kallikrein and bradykinin infusions. However, the peak concentration was found 5 minutes after bradykinin infusion but 60-120 minutes after kallikrein infusion, suggesting different mechanisms leading to the t-PA release. Concomittant with the maximun t-PA concentration there was a marked reduction of the plasminogen activator inhibitor (PAI) concentration. Three hours after drug infusions the PAI concentration was at or above preinfusion level. Kallikrein infusions caused a 10-20 fold increase of the urinary excretion of 2,3-dinor thromboxane B2 (metabolite of TxA2) and a 3-42 fold increase of 2,3-dinor-6-keto-PGFlalpha (metabolite of PGI2) excretion respectively. Corresponding data for bradykinin infusions were, 1.6-5 fold and 2-10 fold increases respectively. Possible links between leucocyte aggregation, prostanoid formation and fibrinolytic variables will be discussed.
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Rajoelimanana, Andry, Pieter Meintjes, and Phil Charles. "Diagnostic Studies for Excretion Be - Star Disc Evolution in Be/X-Ray Binary Systems Utilizing SALT Spectroscopy." In Frontier Research in Astrophysics – II. Trieste, Italy: Sissa Medialab, 2017. http://dx.doi.org/10.22323/1.269.0051.
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Mavuru, Lydia, and Oniccah Koketso Pila. "PRE-SERVICE TEACHERS’ PREPAREDNESS AND CONFIDENCE IN TEACHING LIFE SCIENCES TOPICS: WHAT DO THEY LACK?" In International Conference on Education and New Developments. inScience Press, 2021. http://dx.doi.org/10.36315/2021end023.
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Pre-service teachers’ preparedness and confidence levels to teach is a topical subject in higher education. Previous studies have commented on the role of teacher in-service training in preparing teachers for provision of meaningful classroom experiences to their learners, but many researchers regard pre-service teacher development as the cornerstone. Whilst teacher competence can be measured in terms of different variables e.g. pedagogy, knowledge of the curriculum, technological knowledge etc., the present study focused on teacher competency in terms of Life Sciences subject matter knowledge (SMK). The study was framed by pedagogical content knowledge (PCK). The study sought to answer the research question: How do preservice teachers perceive their levels of preparedness and confidence in teaching high school Life Sciences topics at the end of their four years of professional development? In a qualitative study, a total of 77 pre-service teachers enrolled for the Methodology and Practicum Life Sciences course at a university in South Africa participated in the study. Each participant was tasked to identify topic(s)/concept(s) in Life Sciences they felt challenged to teach, provide a critical analysis of the reasons for that and map the way forward to overcome the challenges. This task was meant to provide the pre-service teachers with an opportunity to reflect and at the same time evaluate the goals of the learning programme they had gone through. Pre-service teachers’ perspectives show their attitudes, values and beliefs based on their personal experiences which therefore help them to interpret their teaching practices. The qualitative data was analysed using content analysis. The findings showed that whilst pre-service teachers were competent to teach other topics, the majority felt that they were not fully prepared and hence lacked confidence to teach the history of life on earth and plant and animal tissues in grade 10; excretion in animals particularly the functions of the nephron in grade 11; and evolution and genetics in grade 12. Different reasons were proffered for the lack of preparedness to teach these topics. The participants regarded some of these topics as difficult and complex e.g. genetics. Evolution was considered to be antagonistic to the participants’ and learners’ cultural and religious belief systems. Hence the participants had negative attitudes towards them. Some of the pre-service teachers indicated that they lacked interest in some of the topics particularly the history of life on earth which they considered to be more aligned to Geography, a subject they did not like. As remedies for their shortcomings in the content, the pre-service teachers planned to co-teach these topics with colleagues, and others planned to enrol for content enrichment programmes. These findings have implications for teacher professional development programmes.