Journal articles: 'Dose activity relation'

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Lee, I.-Min. "Dose-Response Relation Between Physical Activity and Fitness." JAMA 297, no. 19 (May 16, 2007): 2137. http://dx.doi.org/10.1001/jama.297.19.2137.

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Proper, K. I. "Dose-response relation between physical activity and sick leave." British Journal of Sports Medicine 40, no. 2 (February 1, 2006): 173–78. http://dx.doi.org/10.1136/bjsm.2005.022327.

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Toplan, S., D. Ozcelik, and M. C. Akyolcu. "Study on relation between fibrinolytic activity and different dose lithium applications." Trace Elements and Electrolytes 20, no. 10 (October 1, 2003): 208–10. http://dx.doi.org/10.5414/tep20208.

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MARK, AMY E., and IAN JANSSEN. "Dose-Response Relation between Physical Activity and Blood Pressure in Youth." Medicine & Science in Sports & Exercise 40, no. 6 (June 2008): 1007–12. http://dx.doi.org/10.1249/mss.0b013e318169032d.

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Xiang, Man, Xiangli Gu, Xiaoxia Zhang, Samantha Moss, Chaoqun Huang, Larry Paul Nelson, and Tao Zhang. "Psychosocial Mechanism of Adolescents’ Depression: A Dose-Response Relation with Physical Activity." Children 7, no. 4 (April 24, 2020): 37. http://dx.doi.org/10.3390/children7040037.

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Depression has become the most prevalent mental health problem in developing countries, and especially among adolescents. Lubans and his colleagues proposed a psychosocial mechanism to understand the trajectory of mental health (i.e., depression). Thus, this study aimed (1) to examine the relations between different doses of physical activity (PA), light PA (LPA), moderate PA (MPA), and vigorous PA (VPA), academic self-efficacy, and depression among adolescents, and (2) to investigate the direct and indirect relations of various doses of PA to depression through academic self-efficacy among middle school adolescents. Participants were 428 (235 boys, Mean age = 13.7) adolescents recruited from two middle schools in China. They completed previously validated questionnaires to measure different intensity levels of PA (LPA, MPA, and VPA), academic self-efficacy, and depression. There were significant associations of academic self-efficacy with three different doses of PA (p < 0.01). Both LPA and MPA were negatively associated with depression but not VPA. Structural equation modeling (SEM) revealed a well-fit model suggesting the psychosocial pathway from different doses of PA to depression through academic self-efficacy. Findings of this study indicated that academic self-efficacy regulates adolescents’ depression. Tailoring different intensities of PA benefits adolescents’ academic self-efficacy by framing the positive and supportive environment in schools, which can potentially reduce the prevalence of depression during adolescence.

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LEE, I.-MIN, and PATRICK J. SKERRETT. "Physical activity and all-cause mortality: what is the dose-response relation?" Medicine and Science in Sports and Exercise 33, Supplement (June 2001): S459—S471. http://dx.doi.org/10.1097/00005768-200106001-00016.

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Sapkota, Sanjeeb, Michelle M. Yore, and Harold W. Kohl. "Walking, Physical Activity and Lipid/ Lipoprotein Relation - Is There a Dose Response?" Medicine & Science in Sports & Exercise 38, Supplement (May 2006): S303. http://dx.doi.org/10.1249/00005768-200605001-02182.

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Barlow, Carolyn E., Shannon J. FitzGerald, Benjamin L. Willis, Harold W. Kohl, and William L. Haskell. "Dose-response Relation Of Physical Activity Volume And Cardiorespiratory Fitness In Men." Medicine & Science in Sports & Exercise 41 (May 2009): 146. http://dx.doi.org/10.1249/01.mss.0000354088.41618.f6.

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Xu, Lin, Chao Qiang Jiang, Tai Hing Lam, Wei Sen Zhang, G. Neil Thomas, and Kar Keung Cheng. "Dose-Response Relation Between Physical Activity and Cognitive Function: Guangzhou Biobank Cohort Study." Annals of Epidemiology 21, no. 11 (November 2011): 857–63. http://dx.doi.org/10.1016/j.annepidem.2011.06.002.

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Biradar, Yogesh S., Sheetal Jagatap, K. R. Khandelwal, and Smita S. Singhania. "Exploring of Antimicrobial Activity of TriphalaMashi—AnAyurvedicFormulation." Evidence-Based Complementary and Alternative Medicine 5, no. 1 (2008): 107–13. http://dx.doi.org/10.1093/ecam/nem002.

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TriphalaMashiis an ayurvedic formulation that was prepared in our lab. Aqueous and alcoholic extracts of both Triphala and TriphalaMashiwere used, to evaluate antimicrobial activity. Comparative phytochemical profile of Triphala and TriphalaMashiwas done by preliminary phytochemical screening, total phenolic content and thin layer chromatography (TLC). Antimicrobial activity includes isolation of pathogens from clinical samples, its characterization, testing its multiple drug resistance against standard antibiotics and antimicrobial activity of aqueous and alcoholic extracts of both Triphala and TriphalaMashiagainst these organisms by using agar gel diffusion method. TriphalaMashicontaining phenolic compounds, tannins exhibited comparable antimicrobial activity in relation to Triphala against all the microorganisms tested. It inhibits the dose-dependent growth of Gram-positive and Gram-negative bacteria. In conclusion, it appears that TriphalaMashihas non-specific antimicrobial activity.

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Armstrong, Neil, and Bruce Simons-Morton. "Physical Activity and Blood Lipids in Adolescents." Pediatric Exercise Science 6, no. 4 (November 1994): 381–405. http://dx.doi.org/10.1123/pes.6.4.381.

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A computer search was complemented with an extensive hand search of bibliographies of located studies. All controlled trials, studies of trained versus untrained subjects, and reports of habitual physical activity in relation to lipid profile were analyzed and tabulated. The high-risk population was represented by controlled trials that reported relevant data. More convincing evidence for a beneficial effect of physical activity on blood lipids is apparent in cross-sectional studies. The results of longitudinal studies are unimpressive, but the studies are generally lacking in rigor. Empirical dose-response data relating the effects of physical activity to blood lipids in adolescents are nonexistent. Recommendations for an appropriate exercise prescription must therefore be based upon adult data and expert opinion. Emphasis should be placed upon promoting an increase in the amount of adolescents’ habitual physical activity.

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Franklin, Barry A., Leonard A. Kaminsky, and Peter Kokkinos. "Quantitating the Dose of Physical Activity in Secondary Prevention: Relation of Exercise Intensity to Survival." Mayo Clinic Proceedings 93, no. 9 (September 2018): 1158–63. http://dx.doi.org/10.1016/j.mayocp.2018.07.014.

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Snawder, J. E., A. L. Roe, R. W. Benson, and D. W. Roberts. "Loss of CYP2E1 and CYP1A2 Activity as a Function of Acetaminophen Dose: Relation to Toxicity." Biochemical and Biophysical Research Communications 203, no. 1 (August 1994): 532–39. http://dx.doi.org/10.1006/bbrc.1994.2215.

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Yasui, Norio, Koichi Otani, Tadashi Ohkubo, Takako Osanai, Kazunobu Sugawara, Kan Chiba, Takashi Ishizaki, and Sunao Kaneko. "Single-Dose Pharmacokinetics and Pharmacodynamics of Oral Triazolam in Relation to Cytochrome P4502C19 (CYP2C19) Activity." Therapeutic Drug Monitoring 19, no. 4 (August 1997): 371–74. http://dx.doi.org/10.1097/00007691-199708000-00001.

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Chadwick, I. G., M. Kraskiewicz, W. W. Yeo, K. S. Higgins, P. R. Jackson, and L. E. Ramsay. "No Relation between Angiotensin-Converting Enzyme Gene Polymorphism and Dermal Responses to Bradykinin in Healthy Subjects." Clinical Science 91, no. 5 (November 1, 1996): 617–20. http://dx.doi.org/10.1042/cs0910617.

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1. The dermal wheal response to bradykinin is increased by drugs which inhibit angiotensin-converting enzyme, and thus provides a measure of angiotensin-converting enzyme activity at the tissue level. An insertion/deletion polymorphism of the angiotensin-converting enzyme gene predicts serum angiotensin-converting enzyme activity, but its relation to angiotensin-converting enzyme activity in tissue is unclear. 2. The relations between angiotensin-converting enzyme genotype and wheal responses to intradermal bradykinin were studied in 105 healthy subjects: 30 of genotype DD, 51 of genotype ID and 24 of genotype II. Dermal wheal area was measured by digitized planimetry and the angiotensin-converting enzyme genotype by polymerase chain reaction. 3. Bradykinin produced significant linear log dose—wheal area responses. The potency of bradykinin by parallel line bioassay did not differ significantly between the genotypes; the potency in the II subjects relative to DD subjects was 1.25 (95% confidence interval: 0.83–1.88). 4. Although the angiotensin-converting enzyme gene polymorphism is a consistent and powerful predictor of serum angiotensin-converting enzyme activity, it does not appear to predict tissue angiotensin-converting enzyme activity as measured by dermal responses to bradykinin.

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Passmore, A. P., G. B. Kondowe, and G. D. Johnston. "Renal and cardiovascular effects of caffeine: A dose–response study." Clinical Science 72, no. 6 (June 1, 1987): 749–56. http://dx.doi.org/10.1042/cs0720749.

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1. The effects of increasing oral doses of caffeine (45, 90, 180 and 360 mg) on effective renal plasma flow (ERPF), plasma renin activity (PRA), serum electrolytes, plasma noradrenaline, blood pressure and heart rate were studied in eight healthy male volunteers. 2. Urine volume was increased by 360 mg of caffeine only. At caffeine doses greater than 90 mg urinary sodium excretion was significantly increased. There were no changes in ERPF. 3. Serum potassium was significantly reduced by 360 mg of caffeine. 4. Caffeine increased systolic pressure in a dose related manner. Diastolic pressure was also increased, but not in relation to dose. A 360 mg dose of caffeine produced a late increase in heart rate. These changes were not associated with any alterations in PRA or in plasma noradrenaline.

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Bhavani J and Ravichandran S. "Investigating the relation between anti-oxidant activity and epileptic enzymes of formulation-40 capsules." International Journal of Pharmacometrics and Integrated Biosciences 4, no. 1 (July 6, 2020): 6–9. http://dx.doi.org/10.26452/ijpib.v4i1.1212.

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Seizures and Epilepsy are those major conditions that are common symptoms of many diseases that affect the human nervous system. It is one of the most chronic and commonest of the neurological disorders that is prevalent in almost 5crore people around the world. Even though the drugs are effective and potent, there are various side effects and adverse effects are associated with those drugs. General side effects include the nausea and vomitings, many other specific side effects include altered mental consciousness, confusion anorexia and excessive aggression are also noted in many cases of drugs. In this research, herbal formulations were designed to fight back the free radicals that are generated in the brain and those protective enzyme levels were analyzed to estimate the activity of the formulation in the brain tissue. In the research, the prepared formulation showed a dose dependent activity in restoring the brain protective enzymes and balancing them. The formulation contained herb powders that contain antioxidant chemical constituents which helped for the anti-epileptic formulation. The herbal capsules at dose 500mg/kg showed a better activity compared to the standard drug but without notable side effects and adverse effects.

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Khishova, O. M., and V. D. Avdachenok. "STUDYING SEDATIVE ACTIVITY OF COMBINED TINCTURE OF MOTHERWORT AND ST JOHN'S-WORT." Vestnik Farmacii 92, no. 2 (June 30, 2021): 59–64. http://dx.doi.org/10.52540/2074-9457.2021.2.59.

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The paper presents studying sedative activity of the combined tincture of motherwort and St. John's wort. The combined tincture of motherwort and St. John's wort was obtained by percolation method in a ratio 1:10. Standardization of the obtained tincture was carried out with quality indicators: description, content of active ingredients and ethanol, relative density, dry residue. According to all quality indicators, the tincture obtained met the requirements of the State Pharmacopoeia of the Republic of Belarus. Specific sedative activity of the combined tincture of motherwort and St. John's wort was assessed by barbiturates hypnotic effect prolongation (sodium thiopental), by the rate of falling asleep in animals and by animals staying in lateral position in relation to the control group to which sodium thiopental was injected. In the studies carried out it was found that injection of the combined tincture of motherwort and St. John's wort at a dose of 0,1 ml / kg increases sleep by 125,63% and also accelerates the process of falling asleep by 327,75% compared with the separate injection of motherwort and St. John's wort tincture at doses of 0,1 ml/kg. It was shown that the injection of the combined tincture of motherwort and St. John's wort at a dose of 0,1 ml/kg exhibits a potentiated effect and enhances the hypnotic effect of sodium thiopental administered at a dose of 10 mg/kg.

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Rice, K. L., P. G. Duane, G. Mielke, A. A. Sinha, and D. E. Niewoehner. "Calcium ionophores injure alveolar epithelial cells: relation to phospholipase activity." American Journal of Physiology-Lung Cellular and Molecular Physiology 259, no. 6 (December 1, 1990): L439—L450. http://dx.doi.org/10.1152/ajplung.1990.259.6.l439.

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Phospholipases and certain of their hydrolytic products are toxic to alveolar epithelial cells. Since many intracellular phospholipases are Ca2+ dependent, we postulated that elevating cytosolic Ca2+ with ionophores might cause epithelial injury via phospholipase activation. Isolated perfused hamster lungs exposed to an Ca2+ ionophore A23187 develop functional evidence of severe epithelial injury. Ultrastructural studies show widespread lysis of type I epithelial cells, with only minimal abnormalities in other lung cells, including the microvascular endothelium. Analysis of whole lung lipid extracts reveals a modest elevation in free arachidonic acid but no changes in other putative products of phospholipase activity. Parallel studies were performed in cultured cells of pulmonary origin. As measured by 51Cr release, A23187 causes substantial cytotoxicity in 3-day-old cultures of rat type II alveolar epithelial cells (RAEC) but not in cultured bovine pulmonary artery endothelial cells (BPAEC). RAEC prelabeled with [14C]stearic acid [( 14C]SA) and [3H]arachidonic acid [( 3H]AA) release radiolabeled free fatty acids (FFA) in response to A23187 in a dose- and time-dependent manner that parallels the cytotoxicity index. Analyses of putative phospholipase products in cells radiolabeled with [14C]SA and [3H]AA, with [14C]choline, or with [14C]ethanolamine suggest that liberation of radiolabeled FFA may be due to several phospholipases but with principal activity being exhibited by a phospholipase C having specificity toward phosphatidylcholine and phosphatidylethanolamine. Prelabeled BPAEC release only minimal quantities of FFA in response to A23187 under the same conditions. These studies demonstrate that elevations of intracytoplasmic Ca2+ are capable of severely and selectively damaging alveolar epithelial cells and that the injury is associated with activation of intracellular phospholipases. These findings may have implications in regard to the pathogenesis of acute lung injury in humans.

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Shevchuk, Sergii, and Oksanа Pavliuk. "DISORDERS OF STRUCTURAL AND FUNCTIONAL STATE OF BONE TISSUE IN MEN WITH ANKYLOSING SPONDYLITIS, THEIR RELATION TO DISEASE COURSE." Wiadomości Lekarskie 74, no. 8 (2021): 1856–62. http://dx.doi.org/10.36740/wlek202108114.

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The aim: To study the structural and functional state of bone tissue in men with ankylosing spondylitis and to asses its relationship with the course of the disease. Materials and methods: the study was conducted involving 105 men, aged 40.74 ± 0.87 years and 25 generally healthy individuals of the certain age and sex, who formed the control group. The functional ability was assessed by the BASFI index and the disease activity was calculated by ASDAS-CRP and BASDAI. Laboratory criteria for the activity of the inflammatory process were considered erythrocyte sedimentation rate and C-reactive protein. Bone mineral density of the lumbar spine and femoral neck was determined by dual energy X-ray absorptiometry. Results: osteoporosis and osteopenic syndrome were identified in men with ankylosing spondylitis in 27,7% and 29,5% consequently. Disorder of the structural and functional state of bone tissue was closely related to the total indicators of inflammatory activity in ASDAS-CRP (r = –0,36), BASDAI (r = –0,51), the functional index BASFI (r = –0,30), C-reactive protein (r = –0,30) and the cumulative dose of glucocorticoids (r = –0.32). The comparative analysis of densitometric parameters in groups of patients depending on the form of the disease has not shown statistically significant differences. Conclusions: The decrease in bone mineral density in patients with ankylosing spondylitis does not depend on age and duration of the disease, but is associated with the cumulative dose of glucocorticoids and high activity of the inflammatory process.

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Pauleit, D., H. Palmedo, H. Bender, J. Bucerius, S. Ezziddin, V. Klein, F. Grünwald, H. J. Biersack, K. Reichmann, and J. H. Risse. "Therapy of hepatocellular carcinoma with 131I-lipiodol: patient dosimetry." Nuklearmedizin 46, no. 05 (2007): 192–97. http://dx.doi.org/10.1160/nukmed-0086.

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SummaryAim: Dosimetry in 131I-lipiodol therapy for hepatocellular carcinoma (HCC) in the hitherto largest existing patient cohort. Patients, methods: 38 courses of intra-arterial 131I-lipiodol therapy with a total activity up to 6.7 GBq were performed in 18 patients with HCC. Liver and tumour volume were measured by computed tomography (CT) and 131I activity by scintigraphy on day 3, 6, 14, 28 and 42 after injection. Lipiodol deposition in tumour nodules as shown by CT rendered definite attachment to scintigraphic data possible. The radiation dose in tumour nodules, liver and lungs was calculated according to the MIRD concept and the tumour dose related to pre-therapeutic tumour volume, response and survival. Results: Mean tumour dose was 23.6 ± 3.6 Gy (14.2 ± 2.1 mGy/MBq) with maximal 162 Gy (90.1 mGy/MBq) after one and 274 Gy after three courses. The dose to nontumourous liver was 1.9 ± 0.2 Gy (1.2 ± 0.1 mGy/MBq) and the mean dose ratio of tumour / nontumourous liver 11.1 ± 1.7 (max. 82). The pulmonary dose was 25.9 ± 1.8 mGy (16.3 ± 1.2 μGy/MBq) and therefore much lower. There was a reciprocal relation between tumour dose and pretherapeutic tumour volume. Tumour dose had no effect on response or survival. Conclusion: High radiation doses are particularly in small tumour nodes achievable but not necessarily related to tumour response. The dose of non-tumourous liver and lungs is much lower.

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Khon, V. E., N. V. Zagorodniy, V. S. Komlev, I. V. Fadeev, V. G. Bulgakov, N. S. Sergeeva, I. K. Sviridova, E. R. Tolordava, and L. V. Didenko. "NFLUENCE OF THE DEGREE OF CALCIUM SUBSTITUTION BY ARGENTUM IN TRICALCIUM PHOSPHATE ON ITS BIOLOGICAL PROPERTIES IN VITRO." N.N. Priorov Journal of Traumatology and Orthopedics 20, no. 4 (December 15, 2013): 23–28. http://dx.doi.org/10.17816/vto20130423-28.

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Results of in vitro study of argentum containing tricalcium phosphate (TCPh-Ag) are presented. It is shown that biomaterial does not possess radical forming activity. Argentum containing forms of TCPh render bacteriostatic effect upon Staphylococcus haemolyticus and Escherichia coli. Dose-dependent effect of TCPh-Ag in relation to antibacterial and cytotoxic properties is demonstrated. It is determined that TCPh with rated substitution 0.5 is characterized by moderate cytotoxicity with preservation of antibacterial properties.

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Kocic, Gordana, Dusica Pavlovic, Vidosava Djordjevic, Gordana Bjelakovic, and Ivana Stojanovic. "Role of nitric oxide and peroxynitrite in apoptosis - relation to endonuclease activity." Jugoslovenska medicinska biohemija 22, no. 2 (2003): 93–100. http://dx.doi.org/10.2298/jmh0302093k.

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Apoptosis is a form of cell death utilized physiologically to maintain tissue homeostasis, as well as in response to various toxic and inflammatory stimuli or anticancer drugs. Since the process of apoptosis is followed by phagocytosis, the cleavage of DNA to low molecular weight material may serve as a protective function limiting the probability of gene transfer to the nuclei of viable neighbor cells. Many different endonucleases have been proposed as candidates responsible for the internucleosomal cleavage of the genomic DNA observed during apoptosis. The main effect was attributed to the alkaline DNase I (Mg 2+ and caspase-dependent) and acid-DNase II. It was also documented that both of them contain a potential protease (caspase) cleavage site, but they can be also activated upon the influence of other "fragmentation factors", including nitric oxide (NO). The complexity of biological effects induced by NO may be the result of the cell redox state changes, due to its potential interaction with superoxide. The apoptotic effect of both, nitric oxide (NO) and peroxynitrite (ONOO) are dose-dependent and cell-specific may point out the existence of possible "inducible" form of endonuclease.

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Bhagirath, Vinai, John Eikelboom, Jack Hirsh, Michiel Coppens, Jeffrey Ginsberg, Thomas Vanassche, Fei Yuan, Noel Chan, Salim Yusuf, and Stuart Connolly. "Apixaban-Calibrated Anti-FXa Activity in Relation to Outcome Events and Clinical Characteristics in Patients with Atrial Fibrillation: Results from the AVERROES Trial." TH Open 01, no. 02 (July 2017): e139-e145. http://dx.doi.org/10.1055/s-0037-1613679.

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Background In patients with nonvalvular atrial fibrillation (AF), apixaban is given in doses of 5 or 2.5 mg twice daily, according to clinical characteristics. The usual on-treatment range of apixaban drug levels, as determined by apixaban-calibrated anti-factor Xa (anti-Xa) activity, has previously been measured in small cohorts; however, the association between anti-Xa activity and clinical outcomes and the predictors of variability in anti-Xa activity have not been well studied in the AF population. Methods and Results Anti-Xa activity was measured before taking the morning dose, 3 months after enrollment in the AVERROES study using a calibrated anti-Xa assay (Rotachrom). Patients with two of the following criteria—age >80; weight <60 kg; or creatinine >133 μg/L—received 2.5 mg twice daily (n = 145), while all others received 5 mg twice daily (n = 2,247). A total of 2,392 patients were included, with median follow-up of 1.1 years. Median apixaban anti-Xa activity was 122 ng/mL (interquartile range [IQR]: 63–198 ng/mL) for the entire group; 99 ng/mL (IQR: 60–146 ng/mL) for the 2.5-mg group; and 125 ng/mL (IQR: 64–202 ng/mL) for the 5-mg group (p = 0.003). A relationship was evident between bleeding and anti-Xa activity (p = 0.01), which was driven by minor bleeding. No relationship was evident between major bleeding or stroke/systemic embolism and anti-Xa activity. In those receiving the 5-mg dose, estimated glomerular filtration rate, sex, and age had the strongest association with anti-Xa activity. Conclusion There is considerable variability in anti-Xa activity among AF patients receiving apixaban. Rates of major bleeding and stroke/systemic embolism were low irrespective of anti-Xa activity. Clinical Trial Registration ClinicalTrials.gov NCT00496769; https://clinicaltrials.gov/ct2/show/NCT00496769.

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Kalmakhelidz, S., T. Sanikidze, D. Topuria, I. Chkhikvishvili, E. Shekiladze, N. Ivanishvilli, M. Gogebashvili, E. Lomadze, and G. Ormotsadze. "High-sensitive Biomarkers of Blood Antiradical Activity in Mice Exposed to γ-irradiation." International Journal of Innovative Research in Medical Science 6, no. 03 (March 16, 2021): 197–200. http://dx.doi.org/10.23958/ijirms/vol06-i03/1088.

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Diagnostic markers are important indicators for the assessment of the possible consequences of radiation exposure, which could lead to acute and chronic radiation toxicity. The goal of the study is to determine high-sensitive markers of blood redox status in relation to the dose of radiation. The mice were exposed to γ-irradiation (Cs137) at a total dose of 3, 5, and 7Gy. After 1, 2, 7, and 14 days of the irradiation, the blood samples were drawn under ether anesthesia from the inferior vena cava and the activity of antioxidant system (enzymatic -superoxide dismutase (SOD), catalase) and non-enzymatic total antioxidant activity (TAA) of blood serum was determined. The results of our investigation support the fact that the non-enzymatic antioxidant TAA plays an important role in the prevention of radiation damage during ionizing radiation exposure, which makes it possible to consider TAA as a promising candidate as the biomarker of radiation dose.

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Dołhańczuk-Śródka, Agnieszka, Łukasz Wróbel, Andrzej Kłos, and Maria Wacławek. "Assessment of Gamma Dose Rate at Mine Waste Dump." Ecological Chemistry and Engineering S 20, no. 3 (September 1, 2013): 555–65. http://dx.doi.org/10.2478/eces-2013-0031.

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Abstract Exploitation of coal deposits in Upper Silesia is associated with production of large quantities of waste deposited at dumps. The tested samples from five dumps showed different radioactivity from each other. Radioactivity measurements made it possible to analyze the degree of risk with the factors specified by UNSCEAR such as radium equivalent activity Raeq, internal Ein and external Eex occupancy factor. There is a raised level of radiation in dumps as compared with outside dump areas. In the study area, however, there is no risk associated with elevated levels of radiation in relation to standards established by the Council of Ministers of the ionizing radiation dose limits.

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Ricci, Cristian, Federico Gervasi, Maddalena Gaeta, Cornelius M. Smuts, Aletta E. Schutte, and Michael F. Leitzmann. "Physical activity volume in relation to risk of atrial fibrillation. A non-linear meta-regression analysis." European Journal of Preventive Cardiology 25, no. 8 (March 29, 2018): 857–66. http://dx.doi.org/10.1177/2047487318768026.

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Background Light physical activity is known to reduce atrial fibrillation risk, whereas moderate to vigorous physical activity may result in an increased risk. However, the question of what volume of physical activity can be considered beneficial remains poorly understood. The scope of the present work was to examine the relation between physical activity volume and atrial fibrillation risk. Design A comprehensive systematic review was performed following the PRISMA guidelines. Methods A non-linear meta-regression considering the amount of energy spent in physical activity was carried out. The first derivative of the non-linear relation between physical activity and atrial fibrillation risk was evaluated to determine the volume of physical activity that carried the minimum atrial fibrillation risk. Results The dose–response analysis of the relation between physical activity and atrial fibrillation risk showed that physical activity at volumes of 5–20 metabolic equivalents per week (MET-h/week) was associated with significant reduction in atrial fibrillation risk (relative risk for 19 MET-h/week = 0.92 (0.87, 0.98). By comparison, physical activity volumes exceeding 20 MET-h/week were unrelated to atrial fibrillation risk (relative risk for 21 MET-h/week = 0.95 (0.88, 1.02). Conclusion These data show a J-shaped relation between physical activity volume and atrial fibrillation risk. Physical activity at volumes of up to 20 MET-h/week is associated with reduced atrial fibrillation risk, whereas volumes exceeding 20 MET-h/week show no relation with risk.

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Darwash, A. O., G. E. Lamming, and L. M. Hicking. "Oestrus in relation to peak oestradiol levels in ovariectomized Galloway cows." Animal Science 72, no. 2 (January 2001): 401–5. http://dx.doi.org/10.1017/s1357729800055909.

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AbstractThe objective of the present study was to characterize the variation in oestrous behaviour among ovariectomized cows in response to a measured dose of oestradiol benzoate (OB) . In study 1, nine ovariectomized Galloway cows, approximately 10 years old, were challenged with an intramuscular injection of either 0·25, 0·5 or 1·0 mg of OB. Following this, 0·5 mg OB was chosen as the appropriate dose required to induce oestrous behaviour in ovariectomized Galloway cows. In study 2, nine cows injected with 0·5 mg OB were monitored for oestrous behaviour using KAMAR® heat mount detectors. Blood samples for plasma oestradiol-17β (E2) assay were taken every 4 h between 0 to 72 h and once at 96 h, following OB administration. The plasma E2 concentrations between 0 to 96 h following OB administration differed significantly ( P < 0·001) among cows. The interval to peak E2 concentrations averaged 17·42 (s.e. 2·21) h and the mean peak E2 concentration was 5·86 (s.e. 0·57) ng/l. The mean interval from OB administration until onset of mounting activity was 24·57 (s.e.2·38) h and the duration of oestrus averaged 10·5 (s.e. 1·99) h . In all cows, mounting activity occurred following peak E2 concentrations after an average interval of 7·73 (s.e. 1·84) h. There was no significant association between peak E2 concentrations and the interval to onset of mounting activity or its duration. Since the variation among Galloway cows in the manifestation of behavioural oestrus was independent of systemic E2 concentrations, it implies that there are inherent differences between individuals in the sensitivity of the hypothalamus to physiological E2 thresholds. This may help to explain the incidence of silent ovulation in some animals and the occurrence of overt oestrus associated with follicular activity during the luteal phase of the cycle or during the various stages of pregnancy, in the presence of high plasma progesterone concentrations.

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Rost, K. L., and H. Kewitz. "Dose effect relation and time course of thyroid hormone (TH) on choline acetyltransferase activity (ChAT) in newborn rats." European Journal of Pharmacology 183, no. 5 (July 1990): 1942–43. http://dx.doi.org/10.1016/0014-2999(90)92289-u.

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Luik, Annemarie I., Neşe Direk, Lisette A. Zuurbier, Albert Hofman, Eus J. W. Van Someren, and Henning Tiemeier. "Sleep and 24-h activity rhythms in relation to cortisol change after a very low-dose of dexamethasone." Psychoneuroendocrinology 53 (March 2015): 207–16. http://dx.doi.org/10.1016/j.psyneuen.2015.01.011.

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Habila, Nathan, Abel S. Agbaji, Zakari Ladan, Isaac A. Bello, Emmanuel Haruna, Monday A. Dakare, and Taofiq O. Atolagbe. "Evaluation of In Vitro Activity of Essential Oils againstTrypanosoma brucei bruceiandTrypanosoma evansi." Journal of Parasitology Research 2010 (2010): 1–5. http://dx.doi.org/10.1155/2010/534601.

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Essential oils (EOs) fromCymbopogon citratus(CC),Eucalyptus citriodora(EC),Eucalyptus camaldulensis(ED), andCitrus sinensis(CS) were obtained by hydrodistillation process. The EOs were evaluated in vitro for activity againstTrypanosoma brucei brucei(Tbb) andTrypanosoma evansi(T. evansi). The EOs were found to possess antitrypanosomal activity in vitro in a dose-dependent pattern in a short period of time. The drop in number of parasite over time was achieved doses of 0.4 g/ml, 0.2 g/mL, and 0.1 g/mL for all the EOs. The concentration of 0.4 g/mL CC was more potent at 3 minutes and 2 minutes for Tbb andT. evansi, respectively. The GC-MS analysis of the EOs revealed presence of Cyclobutane (96.09%) in CS, 6-octenal (77.11%) in EC, Eucalyptol (75%) in ED, and Citral (38.32%) in CC among several other organic compounds. The results are discussed in relation to trypanosome chemotherapy.

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Rozza, A. L., D. A. S. Cesar, L. G. Pieroni, L. L. Saldanha, A. L. Dokkedal, F. M. De-Faria, A. R. M. Souza-Brito, W. Vilegas, R. K. Takahira, and C. H. Pellizzon. "Antiulcerogenic Activity and Toxicity ofBauhinia holophyllaHydroalcoholic Extract." Evidence-Based Complementary and Alternative Medicine 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/439506.

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Several species ofBauhiniaare used in traditional medicine for the treatment of gastrointestinal diseases, diabetes, and inflammation, among other conditions. The aim of this study was to investigate the antiulcer effect of a hydroalcoholic extract from the leaves ofB. holophylla. The chemical profile of the extract was determined by HPLC-PAD-ESI-IT-MS. A dose-effect relation was constructed using the ethanol-induced gastric ulcer model in male Wistar rats. Histological analyses and studies of antioxidant and anti-inflammatory activities were performed in stomach samples. The involvement of SH compounds, NO,K+ATPchannels, andα2-adrenergic receptors in the gastroprotective effect was evaluated. A toxicity study was performed with a single oral dose of 5000 mg/kg. The extract was composed mainly of cyanoglucoside and flavonol-O-glycosides derivatives of quercetin and myricetin. SH compounds, NO release,K+ATPchannel activation, and presynapticα2-adrenergic receptor stimulation each proved to be involved in the antiulcer effect. The levels of GSH and activity of GR and GPx were increased, and the levels of TNF-α, IL-6 and IL-10 were modulated. There was an antidiarrheal effect and there were no signs of toxicity.B. holophyllapresents antiulcer activity mainly by decreasing oxidative stress and attenuating the inflammatory response, without inducing side effects.

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Welburn, S. C., K. Arnold, I. Maudlin, and G. W. Gooday. "Rickettsia-like organisms and chitinase production in relation to transmission of trypanosomes by tsetse flies." Parasitology 107, no. 2 (August 1993): 141–45. http://dx.doi.org/10.1017/s003118200006724x.

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SUMMARYRickettsia-like organisms (RLO) from tsetse midguts and mosquito cell cultures showed high levels of endochitinase activity. A line of Glossina morsitans morsitans highly susceptible to midgut trypanosome infection and with high incidence of RLO infection showed significantly greater chitinolytic activity than G. austeni which had low RLO incidence and were correspondingly refractory to midgut infection. Midgut infection rates of Trypanosoma brucei rhodesiense in G. m. morsitans showed a dose-related increase when flies were fed N-acetyl-D-glucosamine (GlcNAc) in the infective meal and for 4 subsequent days. A model is proposed for susceptibility to trypanosome infection based on the generation of GlcNAc by RLO endochitinase activity in tsetse pupae inhibiting midgut lectin in teneral flies.

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Ogundele, M. O. "A novel anti-inflammatory activity of lysozyme: modulation of serum complement activation." Mediators of Inflammation 7, no. 5 (1998): 363–65. http://dx.doi.org/10.1080/09629359890893.

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Lysozyme is an ubiquitous enzyme found in most biological secretions and leukocytes. This study was aimed at investigating its interaction with other inflammatory mediators on mucosa surfaces, particularly the complement system. Lysozyme has been shown in our present study, to inhibit the haemolytic activity of serum complement in a dose-dependent fashion, when tested within the levels present in normal and inflamed breast-milk samples, and other mucosal secretions. This represents a new antiinflammatory action of lysozym e in relation to the serum complement, and the exact mode of the interaction need further studies.

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KB, Sunil Kumar, Mahesh Kandula, and Sivanesan P. "Preclinical evaluation of CLX-155, a novel prodrug of 5-FU for the treatment of cancer." Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020): e15614-e15614. http://dx.doi.org/10.1200/jco.2020.38.15_suppl.e15614.

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e15614 Background: CLX-155 is a novel prodrug of 5-FU, developed by adding two acetyl groups (ester bond) and a caprylic acid moiety (amide bond) to 5'-DFCR ring structure. CLX-155 is designed to have a differentiated ADME profile, with improved safety and efficacy over capecitabine. Here, we present the preclinical data of CLX-155 in comparison with capecitabine. Methods: Solubility/stability of CLX-155 was studied in buffers, simulated gastrointestinal fluids and liver microsomes. In vitro metabolite profiling in hepatocytes was done following standard protocol. An oral (gavage) dose range finding (DRF) toxicity, comparative oral pharmacokinetic study and antitumor activity in HCT-116 human colon cancer cell xenograft model was conducted in mice. DRF study in mice evaluated the toxicity of CLX-155 when administered at once daily doses of 100 to 1000 mg/kg/day for 7-days. The oral pharmacokinetics CLX-155/metabolites (5'-DFCR, 5'-DFUR and 5-FU) was determined in mice at MTD dose of 500 mg/kg and for capecitabine at 1000 mg/kg. Antitumor activity of CLX-155 was evaluated in Foxn1 athymic mice at 125, 250 and 500 mg/kg/day and for capecitabine at 1000 mg/kg/day. Treatment was performed for three consecutive weeks (5 days on; 2 days off per week). Results: The results of in-vitro studies confirmed an acceptable profile for further development of CLX-155. Maximum tolerated dose of CLX-155 in mice was 500 mg/kg/day. The key toxicity findings were consistent with the mechanism of action and comparable with capecitabine. Oral PK study in mice showed a lower plasma Cmax for 5'-DFCR, 5'-DFUR and 5-FU. Plasma AUCs of the metabolites were close to or higher than that of capecitabine, indicating an extended absorption or altered metabolism in comparison with capecitabine. CLX-155 caused significant, tumor growth inhibition at all the dose levels tested. Complete tumor regression was seen in 2/10 animals at 500 mg/kg/day of CLX-155. CLX-155 was better tolerated in the mouse xenograft study, no mortality in CLX-155 versus 2/10 in capecitabine group. Conclusions: CLX-155 has an excellent safety and a differentiated ADME profile in relation to capecitabine. This translated into an improved in-vivo antitumor activity for CLX-155 in the HCT 116 xenograft model in relation to capecitabine. Overall data indicate that CLX-155 could offer significant improvements over the currently approved capecitabine in terms of dose size, frequency of administration, safety and interpatient variability in pharmacokinetics.

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Koklin, Ivan S., and Lyudmila M. Danilenko. "Combined use of arginase II and tadalafil inhibitors for the correction of monocrotaline pulmonary hypertension." Research Results in Pharmacology 5, no. 3 (September 30, 2019): 79–85. http://dx.doi.org/10.3897/rrpharmacology.5.39522.

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Introduction: The concept of the regulatory role of endothelium in the pathogenesis of pulmonary hypertension (PH) is fundamental. Research objective: To study the protective effects of the selective arginase II inhibitors L207-0525 and L327-0346 in combination with tadalafil in a monocrotaline model of pulmonary hypertension in rats. Materials and methods: Monocrotaline-induced pulmonary hypertension was simulated in 10 animals by a subcutaneous injection of an alcohol-water solution of monocrotaline (MCT) in the dose of 60 mg/kg. Seven days after the injection of MCT, the administration of L207-0525 and L327-0346 in the doses of 1 mg/kg and 3 mg/kg was started. The compounds were administered intragastrically once a day for 21 days. Results and discussion: It was found that L207-0525 and L327-0346 in the dose of 3 mg/kg and tadalafil in the dose of 1 mg/kg prevented the development of pulmonary hypertension, which was expressed in a statistically significant decrease in the coefficient of endothelial dysfunction (CED, prevention of an increase in systolic pressure in the right ventricle, as well as Fulton, RV/BW and WT indices. The greatest activity was shown by L207-0525 and L327-0346 in the dose of 3 mg/kg in combination with tadalafil in the dose of 0.1 mg/kg. Conclusions: The received results suggest the dose-dependent protective activity of selective arginase II inhibitors L207-0525 and L327-0346 and the development of the additive effect of their combined use with low doses of PDE-5 inhibitor tadalafil in relation to the development of monocrotaline pulmonary hypertension.

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Sakoda, Akihiro, Yuu Ishimori, Norie Kanzaki, Hiroshi Tanaka, Takahiro Kataoka, Fumihiro Mitsunobu, and Kiyonori Yamaoka. "Dosimetry of radon progeny deposited on skin in air and thermal water." Journal of Radiation Research 62, no. 4 (May 31, 2021): 634–44. http://dx.doi.org/10.1093/jrr/rrab030.

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Abstract It is held that the skin dose from radon progeny is not negligibly small and that introducing cancer is a possible consequence under normal circumstances as there are a number of uncertainties in terms of related parameters such as activity concentrations in air and water, target cells in skin, skin covering materials, and deposition velocities. An interesting proposal has emerged in that skin exposure to natural radon-rich thermal water as part of balneotherapy can produce an immune response to induce beneficial health effects. The goal of this study was to obtain generic dose coefficients with a focus on the radon progeny deposited on the skin in air or water in relation to risk or treatment assessments. We thus first estimated the skin deposition velocities of radon progeny in air and thermal water based on data from the latest human studies. Skin dosimetry was then performed under different assumptions regarding alpha-emitting source position and target cell (i.e. basal cells or Langerhans cells). Furthermore, the impact of the radon progeny deposition on effective doses from all exposure pathways relating to ‘radon exposure’ was assessed using various possible scenarios. It was found that in both exposure media, effective doses from radon progeny inhalation are one to four orders of magnitude higher than those from the other pathways. In addition, absorbed doses on the skin can be the highest among all pathways when the radon activity concentrations in water are two or more orders of magnitude higher than those in air.

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Toader, E., R. M. McAllen, A. Cividjian, R. L. Woods, and L. Quintin. "Effect of systemic B-type natriuretic peptide on cardiac vagal motoneuron activity." American Journal of Physiology-Heart and Circulatory Physiology 293, no. 6 (December 2007): H3465—H3470. http://dx.doi.org/10.1152/ajpheart.00528.2007.

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Intravenous B-type natriuretic peptide (BNP) enhances the bradycardia of reflexes from the heart, including the von Bezold-Jarisch reflex, but its site of action is unknown. The peptide is unlikely to penetrate the blood-brain barrier but could act on afferent or efferent reflex pathways. To investigate the latter, two types of experiment were performed on urethane-anesthetized (1.4 g/kg iv) rats. First, the activity was recorded extracellularly from single cardiac vagal motoneurons (CVMs) in the nucleus ambiguus. CVMs were identified by antidromic activation from the cardiac vagal branch and by their barosensitivity. Phenyl biguanide (PBG), injected via the right atrium in bolus doses of 1–5 μg to evoke the von Bezold-Jarisch reflex, caused a dose-related increase in CVM activity and bradycardia. BNP infusion (25 pmol·kg−1·min−1 iv) significantly enhanced both the CVM response to PBG ( n = 5 rats) and the reflex bradycardia, but the log-linear relation between those two responses over a range of PBG doses was unchanged by BNP. The reflex bradycardia was not enhanced in five matched time-control rats receiving only vehicle infusions. In five other rats the cervical vagi were cut and the peripheral right vagus was stimulated supramaximally at frequencies of 1–20 Hz. The bradycardic responses to these stimuli were unchanged before, during, and after BNP infusion. We conclude that systemic BNP in a moderate dose enhances the von Bezold-Jarisch reflex activation of CVM, in parallel with the enhanced reflex bradycardia. That enhancement is due entirely to an action before the vagal efferent arm of the reflex pathway.

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Diamant, M., and D. De Wied. "Differential effects of centrally injected AVP on heart rate, core temperature, and behavior in rats." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 264, no. 1 (January 1, 1993): R51—R61. http://dx.doi.org/10.1152/ajpregu.1993.264.1.r51.

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After intracerebroventricular (icv) injection of arginine-vasopressin (AVP; 0.1, 1, 3, 10, 30 and 100 ng) or artificial cerebrospinal fluid (aCSF), heart rate (HR), core temperature (CT), and gross activity were monitored by a wireless telemetry system in rats in the home cage for a 60-min period. In addition, the simultaneous occurrence of various behaviors was recorded by an observer. Also, two structurally related peptides, oxytocin (OXT) and desglycinamide-arginine vasopressin (DGAVP), were tested (10 and 100 ng). Both the time-effect and dose-response relationships of AVP-induced changes in HR and CT were biphasic. Lower doses of AVP produced a tachycardia, whereas injection of higher doses of AVP caused a tachycardia preceded by a significant bradycardia. The concomitant mild rise in CT seen in rats treated with 1 and 3 ng AVP or with aCSF was attenuated in rats given 10 ng AVP; 30 ng AVP resulted in an immediate significant fall in CT, which was restored to control values at 30 min after administration. An inverted U-shaped dose-response relationship was observed for gross activity, locomotion, and rearing behavior, whereas grooming behavior was most marked after the highest dose of AVP. OXT induced a grooming response and cardiac acceleration at the 100-ng dose only, whereas DGAVP produced no effect. To investigate the role of endogenous AVP in the maintenance of tonic ANS activity under resting conditions, rats were treated intracerebroventricularly (icv) with the V1 antagonist d(CH2)5-[Tyr(Me)2]AVP or polyclonal antiserum (W1E) against AVP. During the first 10 min after icv injection of 3 and 10 ng of the antagonist, an increase in HR, CT, and behavioral activation was observed, effects opposite to those produced by the higher dose of AVP. The same variables remained unchanged after administration of 100 ng of the antagonist. W1E injected icv was without effect. In summary, central effects of AVP on autonomic and behavioral activity seem to be mediated by differential neural pathways. In addition, a structure-activity relation seems to exist for the AVP-induced effects. Finally, these results suggest that AVP plays but a minor role in the maintenance of tonic activity of the ANS.

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Seo, Sang-Hwan, Young-Choon Lee, and Hyung-In Moon. "Acetyl-cholinesterase Inhibitory Activity of Methoxyflavones Isolated from Kaempferia parviflora." Natural Product Communications 12, no. 1 (January 2017): 1934578X1701200. http://dx.doi.org/10.1177/1934578x1701200107.

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MeOH extracts of Kaempferia parviflora Wall. ex. Baker, family Zingiberaceae, were consecutively partitioned with CHCl3, EtOAc, and n-BuOH. The CHCl3 fractions were diluted in distilled water with n-hexane–CH2Cl2 and three methoxyflavones were isolated from the CH2Cl2 extract. Based on spectral analysis and comparison of the spectral data with literature values, the compounds were identified as 3,5,7,3′,4′-pentamethoxyflavone (KP1), 5,7-dimethoxyflavone (KP2), and 5,7,4′-trimethoxyflavone (KP3). In relation to their possible effectiveness against Alzheimer's disease, these compounds were tested for their ability to inhibit acetylcholinesterase activity and neurite outgrowth in the PC12 cell line. Of the three compounds, KP1 was the only one to inhibit significantly the acetylcholinesterase activity in a dose-dependent manner.

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Li, S., E. Sehic, Y. Wang, A. L. Ungar, and C. M. Blatteis. "Relation between complement and the febrile response of guinea pigs to systemic endotoxin." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 277, no. 6 (December 1, 1999): R1635—R1645. http://dx.doi.org/10.1152/ajpregu.1999.277.6.r1635.

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We reported recently that the complement (C) system may play a role in the febrile response of guinea pigs to intravenous lipopolysaccharide (LPS) administration because C depletion abolished the LPS-induced rise in core temperature (Tc). The present study was designed to investigate further the relation between C reduction [induced by cobra venom factor (CVF); 20, 50, 100, and 200 U/animal iv] and the fever of adult, conscious guinea pigs produced by LPS injected intravenously (2 μg/kg) or intraperitoneally (8, 16, 32 μg/kg) 18 h after CVF; control animals received pyrogen-free saline. Serum C levels were measured as total hemolytic C activity before and 18 h after CVF injection and expressed as CH100units. In other experiments, serum C levels were determined at various intervals after the intravenous and intraperitoneal injections at different doses of LPS alone. LPS produced fevers generally of similar heights but of different onset latencies and durations, depending on the dose and route of administration. CVF caused dose-related reductions in serum C, from ∼1,136 U to below detection. These reductions proportionately attenuated the fevers induced by intraperitoneal LPS, but not by intravenous LPS. Intravenous and intraperitoneal LPS per se caused reductions in serum C of 25 and 40%, respectively, indicating activation of the C cascade. These decreases were transient, however, occurring early during the febrile rise ∼30 min after LPS injection. These data thus support the notion that the C system may be critically involved in the febrile response of guinea pigs to systemic, particularly intraperitoneal, LPS.

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Mendonça, Nuno, Linda M. Hengeveld, Marjolein Visser, Nancy Presse, Helena Canhão, Eleanor M. Simonsick, Stephen B. Kritchevsky, Anne B. Newman, Pierrette Gaudreau, and Carol Jagger. "Low protein intake, physical activity, and physical function in European and North American community-dwelling older adults: a pooled analysis of four longitudinal aging cohorts." American Journal of Clinical Nutrition 114, no. 1 (April 7, 2021): 29–41. http://dx.doi.org/10.1093/ajcn/nqab051.

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ABSTRACT Background Dietary protein may slow the decline in muscle mass and function with aging, making it a sensible candidate to prevent or modulate disability progression. At present, studies providing reliable estimates of the association between protein intake and physical function, and its interaction with physical activity (PA), in community-dwelling older adults are lacking. Objectives We investigated the longitudinal relation between protein intake and physical function, and the interaction with PA. Methods We undertook a pooled analysis of individual participant data from cohorts in the PROMISS (PRevention Of Malnutrition In Senior Subjects in the European Union) consortium (the Health Aging and Body Composition Study, Quebec Longitudinal Study on Nutrition and Successful Aging, Longitudinal Aging Study Amsterdam, and Newcastle 85+) in which 5725 community-dwelling older adults were followed up to 8.5 y. The relation between protein intake and walking speed was determined using joint models (linear mixed-effects and Cox proportional hazards models) and the relation with mobility limitation was investigated using multistate models. Results Higher protein intake was modestly protective of decline in walking speed in a dose-dependent manner [e.g., protein intake ≥1.2 compared with 0.8 g/kg adjusted body weight (aBW)/d: β = 0.024, 95% CI: 0.009, 0.032 SD/y], with no clear indication of interaction with PA. Participants with protein intake ≥0.8 g/kg aBW/d had also a lower likelihood of incident mobility limitation, which was observed for each level of PA. This association seemed to be dose-dependent for difficulty walking but not for difficulty climbing stairs. No associations between protein intake and other mobility limitations transitions were observed. Conclusions Higher daily protein intake can reduce physical function decline not only in older adults with protein intake below the current RDA of 0.8 g/kg BW/d, but also in those with a protein intake that is already considered sufficient. This dose-dependent association was observed for each level of PA, suggesting no clear synergistic association between protein intake and PA in relation to physical function.

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Turgunov, E., M. F. Faizullaeva, K. Kh Darmaganbet, and L. A. Zhusupova. "STIMULATING AND INHIBITING EFFECTS ON PLANTS OF SOME ACETYLENIC AMINO ALCOHOLS AND SALTS GUIDAMONACI." Bulletin of Korkyt Ata Kyzylorda University 56, no. 1 (2021): 33–40. http://dx.doi.org/10.52081/bkaku.2021.v56.i1.003.

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The herbicidal effects of aminopentinols, aminohexinols and some synthesized acetylene aminospirths, hydrochloride compounds, as well as the biological activity of their effects in relation to such important crops as cotton and corn were studied. During pretreatment of seeds and weeds, it was found that the studied drugs show different herbicidal activity in relation to annual dicotyledonous and annual grain weeds, depending on their chemical composition and dosage. It has been established that many ammonium salts of acetylene amino alcohols have high biological activity and that their use, depending on the chemical structure and quantity, has biological effects. To determine the biological activity of the studied drugs, the authors used a well-known method of biotestylation in wheat coleoptile. Preemergence treatment by solutions of abovementioned preparates in dependence on their chemical structure and dose have rendered different action on the growth leguminous (nut) and cereals (wheat, sorghum) plants.

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Smirnov, V. S., I. A. Leneva, T. A. Kudryavtseva, E. B. Fayzuloev, V. A. Zaplutanov, S. V. Petlenko, N. P. Kartashova, A. V. Gracheva, and E. R. Korchevaya. "Possibilities of suppressing the cytopathogenic effect of SARS-CoV-2 coronavirus according to the results of the antiviral activity of Cytovir®-3 in vitro study." Antibiotics and Chemotherapy 66, no. 5-6 (August 30, 2021): 4–10. http://dx.doi.org/10.37489/0235-2990-2021-66-5-6-4-10.

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Introduction. The COVID-19 pandemic has stimulated the search for drugs with speciﬁc antiviral activity against the new pathogenic strain of the SARS-CoV-2 coronavirus. First of all, scientiﬁc search was aimed at studying drugs with already proven eﬃcacy against inﬂuenza and ARVI. The aim of this work was to study the antiviral activity of Cytovir®-3 in vitro in relation to the cytopathogenic eﬀect of the SARS-CoV-2 virus. Material and methods. The antiviral activity of the drug Cytovir®-3 against the SARS-CoV-2 virus was studied in experimental models in vitro on Vero CCL81 cell culture (ATCC). The maximum tolerated concentration and the 50% cytotoxic dose were determined using a quantitative microculture tetrazolium test assay to calculate the working range of the concentrations of the test drug. Results and discussion. As a result of the study, it was shown that the greatest activity of the drug was manifested when it was added to the cells 24 hours before and 1 hour and 24 hours after viral infection, the inhibition level reached 53% (>IC50) at the drug concentrations of 105, 55, and 85 µg/ml, respectively. Cytovir®-3 suppressed the viral activity of SARS-CoV-2 in the dose range from 10 µg/ml to 105 µg/ml under the indicated infection conditions. It was found that the drug did not exhibit cytotoxic eﬀects on the Vero cell culture in the range of antiviral doses. Conclusion. The antiviral activity of Cytovir®-3 against the SARS-CoV-2 virus has been proven due to the achievement of IC50, which is below the maximum tolerated dose of 149 µg/ml.

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Schiffelers, Raymond M., Gert Storm, Marian T. ten Kate, and Irma A. J. M. Bakker-Woudenberg. "Therapeutic Efficacy of Liposome-Encapsulated Gentamicin in Rat Klebsiella pneumoniae Pneumonia in Relation to Impaired Host Defense and Low Bacterial Susceptibility to Gentamicin." Antimicrobial Agents and Chemotherapy 45, no. 2 (February 1, 2001): 464–70. http://dx.doi.org/10.1128/aac.45.2.464-470.2001.

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ABSTRACT Long-circulating liposomes (LCL) may be used as targeted antimicrobial drug carriers as they localize at sites of infection. As a result, LCL-encapsulated gentamicin (LE-GEN) has demonstrated superior antibacterial activity over the free drug in a single-dose study of immunocompetent rats with Klebsiella pneumoniaepneumonia. In the present study, the therapeutic efficacy of LE-GEN was evaluated by monitoring rat survival and bacterial counts in blood and lung tissue in clinically relevant models, addressing the issue of impaired host defense and low bacterial antibiotic susceptibility. The results show that in immunocompetent rats infected with the high-GEN-susceptibility K. pneumoniae strain, a single dose of LE-GEN is clearly superior to an equivalent dose of free GEN. Yet complete survival can also be obtained with multiple doses of free GEN. In leukopenic rats infected with the high-GEN-susceptible K. pneumoniae strain, free GEN at the maximum tolerated dose (MTD) was needed to obtain survival. However, with the addition of a single dose of LE-GEN to free-GEN treatment, complete survival can be obtained using a sevenfold-lower cumulative amount of GEN than with free-GEN treatment alone. In leukopenic rats infected with low-GEN-susceptibleK. pneumoniae cells, free GEN at the MTD did not result in survival. The use of LE-GEN is needed for therapeutic success. Increasing LE-GEN bilayer fluidity resulted in an increased GEN release from the liposomes and hence improved rat survival, thus showing the importance of the liposome lipid composition for therapeutic efficacy. These results warrant further clinical studies of liposomal formulations of aminoglycosides in immunocompromised patients with severe infections.

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Dziura, James, Stanislav V. Kasl, and Loretta Di Pietro. "Physical Activity Reduces Type 2 Diabetes Risk in Aging Independent of Body Weight Change." Journal of Physical Activity and Health 1, no. 1 (January 2004): 19–28. http://dx.doi.org/10.1123/jpah.1.1.19.

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Background:It is not clear whether physical activity can exert a protective role on diabetes risk in older people that is independent of the changes in body weight that occur with both aging and disuse. The purpose of this analysis was to determine the relation between current physical activity, 3-year change in body weight, and the subsequent risk of type 2 diabetes in an older cohort.Methods:We studied prospectively 2,135 older (≥65 years) persons living in New Haven, CT, between 1982 and 1994. Physical activity was self-reported in 1982 and again in 1985; body weight and diabetes were self-reported annually over 12 years. Data were analyzed using multivariable Cox Proportional Hazards modeling with adjustments for age, sex, race, education, body mass index (BMI), smoking, chronic conditions, physical function, and alcohol intake.Results:Although an inverse graded relation was observed between level of activity and rate of diabetes, this dose–response relation did not reach statistical significance. However, older people who reported at least some activity at baseline experienced a significantly lower rate of diabetes between 1983 and 1994 compared to those reporting no activity (RR = 0.55; 95%CI = 0.35, 0.87). When 3-year changes in physical activity and body weight between 1982 and 1985 were added to the model, the relation between physical activity and reduced diabetes risk was unchanged (RR = 0.49; 95%CI = 0.24, 0.99).Conclusions:Even in advanced age, physical activity exerts an important and independent role in the prevention of type 2 diabetes. Continued physician counseling on the health effects of physical activity and referrals to community-based exercise programs should be encouraged among older people.

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Yu, Hongyang, Runxuan Chu, Xue Li, Bing Wang, Wei Chen, Shuang Zhou, Huiyan Chen, et al. "Interaction of Humic Acid with Graphene Oxide: Relation to Antibacterial Activities Against Escherichia coli." Journal of Nanoscience and Nanotechnology 21, no. 3 (March 1, 2021): 1430–38. http://dx.doi.org/10.1166/jnn.2021.18953.

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Graphene oxide (GO) sheets attracted great attention as effectively antibacterial agents in water treatment and environmental remediation applications. In the study, the interaction of humic acid (HA) as the model of natural organic matter (NOM) with GO and their antibacterial activities against Escherichia coli (E. coli) was investigated. The interaction between GO and HA molecules was analyzed by isothermal titration calorimetry (ITC) and fluorescence spectroscopy analysis. The study demonstrated that GO reaction with HA was a spontaneously exothermic process, which enabled formation of stable and well dispersed GO-HA complex in aqueous solution. Both GO and GO-HA could significantly inhibit the growth of E. coli and present dose-dependent bactericidal property. GO and GO-HA showed more obvious antibacterial activity in saline solution than in LB broth. We suggest the surface wrinkles of GO and GO-HA could contribute to the firm wrapping of E. coli, which is the principle factor for the antibacterial activity of GO and GO-HA. Especially, GO-HA exhibit less surface wrinkles in comparison with GO, corresponding to its reduced antibacterial activity in saline solution.

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Tfelt-Hansen, Peer, and Jes Olesen. "Possible site of action of CGRP antagonists in migraine." Cephalalgia 31, no. 6 (March 7, 2011): 748–50. http://dx.doi.org/10.1177/0333102411398403.

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Background: The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP antagonists behind the blood-brain barrier (BBB), i.e. in the central nervous system (CNS). Methods: Comparison of doses needed for CGRP blocking effect in vitro with dose needed in vivo in man and monkeys. Discussion of these doses in relation to doses needed for anti-migraine activity. Results: In vivo studies in monkeys and man showed that high doses compared to doses needed in vitro are needed to block capsaicin-induced in skin blood flow, a CGRP-mediated reaction. These doses are close to those needed for anti-migraine activity. Conclusion: The apparently high doses of CGRP receptor antagonists, olcegepant and telcagepant needed for anti-migraine effect are not so high after all. They do not allow a conclusion as to whether CGRP antagonists act on peripheral sites or central sites in migraine.

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Sinués, Blanca, Ana Fanlo, Marĺa Luisa Bernal, Marta Val, and Esteban Mayayo. "Omeprazole treatment: genotoxicity biomarkers, and potential to induce CYP1A2 activity in humans." Human & Experimental Toxicology 23, no. 3 (March 2004): 107–13. http://dx.doi.org/10.1191/0960327104ht431oa.

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Omeprazole is one of the most used acid-suppressing medications. This fact emphasizes the questions concerning the safety of this compound. Healthy volunteers (n-33) were included in this prospective study. All study subjects were analysed for their CYP2C19 genotype. Of the 33 individuals, 24 were homozygous for the wild type CYP2C19*1 allele, 7 were heterozygous for theCYP2C19*2 variant allele, and 2 were homozygous for the CYP2C19*2 variant allele. Before and after 14 days of omeprazole treatment at a daily dose of 20 mg, one blood sample was taken from each individual to determine five cytogenetic biomarkers of genotoxicity: chromosome aberrations, micronuclei, proliferating rate index, sister chromatid exchanges, and mitotic index. The only significant change was that of a weak increase in micro nuclei count after treatment in relation to baseline values (day 0) (P-0.026). To assess the potential of omeprazole to induce P450 CYP1A2, the urinary ratio AFMU-1X-1U/17U in the interval of 4 / 5 hours after caffeine intake was calculated twice (days 0 and 15), using the caffeine test in 27 of the 33 individuals. This result suggests that omeprazole does not increase CYP1A2 activity after 14 days of treatment.

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Skorecki, K. L., A. S. Verkman, C. Y. Jung, and D. A. Ausiello. "Evidence for vasopressin activation of adenylate cyclase by subunit dissociation." American Journal of Physiology-Cell Physiology 250, no. 1 (January 1, 1986): C115—C123. http://dx.doi.org/10.1152/ajpcell.1986.250.1.c115.

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Radiation inactivation is used to probe the sequence of subunit interactions involved in the activation of adenylate cyclase by vasopressin in cultured renal epithelial cells (LLC-PK1) based on our previous analysis of the radiation inactivation of multimeric enzymes [Verkman et al., Am. J. Physiol. 250 (Cell Physiol. 19): C103-C114, 1986]. For basal adenylate cyclase activity, a concave downward ln(activity) vs. dose relation was observed with limiting slope corresponding to a molecular weight of (169-196) X 10(3). Similar results were obtained with NaF. In contrast, addition of vasopressin, guanylyl imidodiphosphate, or forskolin resulted in transition to a linear ln(activity) vs. dose relation with a slope corresponding to a molecular weight similar to that observed for basal activity. These findings were incorporated into a cyclic dissociation model for the hormonal activation of adenylate cyclase (graph see text) where H is hormone, R is receptor, C is catalytic unit, alpha and beta are subunits of guanyl nucleotide-regulatory protein (G), GTP is guanosine triphosphate, and GDP is guanosine diphosphate. The addition of H favors the dissociation of G into alpha and beta subunits by providing a rapid pathway for addition of GTP to dissociated alpha subunits. The observed target size of the active enzyme species formed corresponds to the composite molecular weights of alpha GTP with C. This model consolidates the radiation inactivation findings as well as the known biochemical characteristics for adenylate cyclase.

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Journal articles on the topic 'Dose activity relation'

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