Effects of long-term continuous GnRH administration on the pituitary–gonadal axis in Eld's deer stags (Cervus eldi thamin)

1995 ◽  
Vol 73 (9) ◽  
pp. 1609-1619 ◽  
Author(s):  
S. L. Monfort ◽  
J. L. Brown ◽  
T. C. Wood ◽  
M. Bush ◽  
L. R. Williamson ◽  
...  

Eld's deer stags (Cervus eldi thamin) (in groups of three) were continuously administered gonadotropin-releasing hormone (GnRH) in control, low, medium, or high doses (0, 20.1 ± 0.7, 83.3 ± 2.6, and 292.9 ± 4.9 ng∙kg−1∙d−1, respectively) via osmotic minipumps for ~80 d to investigate the potential for precociously reactivating the pituitary–testicular axis during the nonbreeding season. Secretory patterns of LH, FSH, and testosterone concentrations were qualitatively similar among treatments. However, in the low-dose group, basal LH and FSH concentrations were both increased (p < 0.05) and pituitary responsiveness to a superimposed GnRH challenge was augmented (p < 0.05) after 12 weeks of treatment compared with all other groups. Despite these endocrine changes, continuous low-dose GnRH administration was not effective for precociously inducing testicular activity in this seasonally breeding species. High-dose GnRH administration initially induced a transient increase in LH, FSH, and testosterone secretion and delayed, but did not prevent, the seasonal decline in spermatogenesis. After 6–12 weeks of high-dose GnRH administration, however, attenuated pituitary responsiveness appeared to delay the normal seasonal reactivation of the pituitary–gonadal axis. In conclusion, prolonged, continuous low-dose GnRH administration did not effectively translate into a precocious onset of testicular activity; therefore, this specific approach is unlikely to be useful for prolonging the fertile period in this seasonally breeding species.

2017 ◽  
Vol 7 (1) ◽  
pp. 171
Author(s):  
Hamid Reza Adeli Bhroz ◽  
Kazem Parivar ◽  
Iraj Amiri ◽  
Nasim Hayati Roodbari

Background and Aim: Thyroid is one of the endocrine glands, (T3 and T4) play a significant role in the development of prenatal brain and the following stages. The study aimed to evaluate the effect of hypothyroidism on the amount of expression of NT4, NT3, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in brain of one-day rat neonates with hypothyroidism.Materials and Methods: In total, 25 mature mice of Albino NMRI race were selected after mating, divided into three group, control, as well as low-dose and high-dose intervention groups. Samples of the control group received pure water during pregnancy, whereas subjects of the intervention group with low and high doses of the medication were administered with 20 mg and 100 mg methimazole powder (dissolved in 100 cc water), respectively. After child delivery, blood samples were obtained from mother mice to determine the level of T3 and T4 in blood serum. Following that, the brain of one-day mice were removed by surgery and assessed to determine the amount of expression of NT4, NT3, NGF and BDNF using the complete kit of RT-PCR.Results: Levels of T4 and T3 in the control group were 28 ug/dl and 1.59 ug/dl, respectively. In the low-dose intervention group, the amounts of the mentioned hormones were 8 ug/dl and 0.85 ug/dl, significantly, indicating a significant reduction in the expression of NT4, NT3, NGF and BDNF genes, compared to the control group. Moreover, T4 and T3 were 6 ug/dl and 0.79 ug/dl in the high-dose group, respectively, conveying a significant decrease in the expression of NT4, NT3, NGF and BDNF genes, compared to the control group (P<0.05).


2003 ◽  
Vol 77 (24) ◽  
pp. 13323-13334 ◽  
Author(s):  
Yang Wang ◽  
Mario Lobigs ◽  
Eva Lee ◽  
Arno Müllbacher

ABSTRACT C57BL/6J mice infected intravenously with the Sarafend strain of West Nile virus (WNV) develop a characteristic central nervous system (CNS) disease, including an acute inflammatory reaction. Dose response studies indicate two distinct kinetics of mortality. At high doses of infection (108 PFU), direct infection of the brain occurred within 24 h, resulting in 100% mortality with a 6-day mean survival time (MST), and there was minimal destruction of neural tissue. A low dose (103 PFU) of infection resulted in 27% mortality (MST, 11 days), and virus could be detected in the CNS 7 days postinfection (p.i.). Virus was present in the hypogastric lymph nodes and spleens at days 4 to 7 p.i. Histology of the brains revealed neuronal degeneration and inflammation within leptomeninges and brain parenchyma. Inflammatory cell infiltration was detectable in brains from day 4 p.i. onward in the high-dose group and from day 7 p.i. in the low-dose group, with the severity of infiltration increasing over time. The cellular infiltrates in brain consisted predominantly of CD8+, but not CD4+, T cells. CD8+ T cells in the brain and the spleen expressed the activation markers CD69 early and expressed CD25 at later time points. CD8+ T-cell-deficient mice infected with 103 PFU of WNV showed increased mortalities but prolonged MST and early infection of the CNS compared to wild-type mice. Using high doses of virus in CD8-deficient mice leads to increased survival. These results provide evidence that CD8+ T cells are involved in both recovery and immunopathology in WNV infection.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4056-4056
Author(s):  
Heinz Gisslinger ◽  
Veronika Buxhofer-Ausch ◽  
Josef Thaler ◽  
Ernst Schlögl ◽  
Gunther Gastl ◽  
...  

Abstract Background Ropeginterferon alfa-2b (AOP2014/P1101) is a novel long-acting pegylated IFN-alpha-2b, composed of mainly one isoform, resulting in longer half-life and exposure time. Reduced dosing frequencies, better tolerability, improved compliance and more favorable long-term treatment outcomes in patients with polycythemia vera (PV) are expected. The drug has Orphan designation by EMA and FDA and is currently in the phase III stage of development. Study design Efficacy and safety data are being collected in the follow-up extension stage of the study (collecting the data of both Phase I and Phase II portions of the study), after the maximum tolerated dose (MTD) of ropeginterferon alfa-2b, administered subcutaneously every 14 to 28 days, has been defined earlier. Patients with confirmed diagnosis of PV, age ≥18 years, both naïve and cytoreductively pre-treated were eligible. After establishing the MTD, an extended cohort of 25 additional patients has been planned to be recruited. Complete hematological response (CR) is defined by hematocrit (Hct)<45%, platelet count≤400*109/L, WBC count≤10*109/L, normal spleen size by sonography, and absence of thromboembolic events. Partial response (PR) is defined as Hct<45% without phlebotomy but with persistent splenomegaly or elevated (>400*109/L) platelet count, or reduction of phlebotomy requirements by at least 50%. Complete molecular response has been defined as reduction of any molecular abnormality to undetectable levels; partial molecular response as: reduction ≥ 50% in patients with < 50% mutant allele burden, or a reduction ≥ 25% in patients with > 50% mutant allele burden. The present analysis was focused on long-term tolerability and safety in correlation with the dose of ropeginterferon alfa-2b in PV. Results Data on treatment as by July, 24, 2015, are covered by the current analysis. Baseline characteristics of the study cohort during short-term treatment were already presented earlier (Gisslinger et al, ASH 2013). The full analysis set and efficacy set were composed of 51 and 47 patients, respectively. Currently, the median reported treatment duration is 138 weeks, 33 patients completed their follow up for two years, 19 for three years. Starting with the week 10, Hct-level, platelet- and WBC-counts could be constantly maintained within normal range in the majority of patients. In a group of patients with the mean administered dose of <300 µg ("low dose", n=36), CR as best individual response was achieved in 20 (56%) patients, and PR in 14 (39%) compared to the CR and PR in the high dose (>300 µg, n=11) group of 8 (73%) and 3 (27%) respectively. However, no statistical significance can be observed if correlation between the dose and response status was analyzed. 30 patients are still being treated in the study. Similarly, no association between the dose and occurrence of adverse events in the study could be observed. Complete molecular response as best individual response was observed more frequently in the high dose group 4 (36%) compared to 8 (23%) in the low dose group, while partial molecular responses were equally frequent in both dose groups (in 6/55% and 20/57%, respectively). 21 patients discontinued the study, 18 being treated with AOP2014 doses corresponding to low, and 3 to the high dose arms, corresponding to the drop-out rate of 50% and 27% in the respective arms. Interestingly, all discontinuations in the high dose group occurred within the first year of treatment (at weeks 16, 18 and 32), while the drop-outs in the low dose group (6 patients, 33%) discontinued the study after completion of their first year of treatment. Conclusions Efficacy and safety profile remain in line with expectations from other (pegylated) interferons. Overall response rate of >80% with cumulative CRs in 45-50%, accompanied by phlebotomy independence, normalization of hematological parameters and spleen size reduction in majority of patients have been observed. Significant and sustained JAK2 allelic burden decrease, starting from week 28 of treatment, was seen. No significant difference between the two mean dose levels regarding response rates or adverse events even during long-term treatment and observation could be observed. These finding are to be further verified in a larger prospective setting. Disclosures Gisslinger: Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau; AOP ORPHAN: Consultancy, Honoraria, Research Funding, Speakers Bureau; Geron: Consultancy; Sanofi Aventis: Consultancy; Janssen Cilag: Honoraria, Speakers Bureau. Buxhofer-Ausch:AOP Orphan: Research Funding. Thaler:AOP Orphan: Research Funding. Schlögl:AOP Orphan: Research Funding. Gastl:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; AOP Orphan: Research Funding. Ban:AOP Orphan: Research Funding. Egle:AOP Orphan: Research Funding. Melchardt:AOP Orphan: Research Funding. Burgstaller:AOP Orphan Pharmaceuticals: Honoraria, Research Funding; Novartis: Honoraria; Mundipharma: Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Willenbacher:COMET Center ONCOTYROL: Research Funding; AOP Orphan: Research Funding. Kralovics:AOP Orphan: Research Funding; Qiagen: Membership on an entity's Board of Directors or advisory committees. Zörer:AOP Orphan: Employment. Ammann-Mwathi:AOP Orphan: Employment. Kadlecova:AOP Orphan: Consultancy. Zagrijtschuk:AOP Orphan: Employment. Klade:AOP Orphan: Employment. Greil:Pfizer: Honoraria, Research Funding; GSK: Research Funding; Boehringer-Ingelheim: Honoraria; AOP Orphan: Research Funding; Celgene: Consultancy; Janssen-Cilag: Honoraria; Genentech: Honoraria, Research Funding; Novartis: Honoraria; Astra-Zeneca: Honoraria; Amgen: Honoraria, Research Funding; Ratiopharm: Research Funding; Sanofi Aventis: Honoraria; Merck: Honoraria; Mundipharma: Honoraria, Research Funding; Eisai: Honoraria; Cephalon: Consultancy, Honoraria, Research Funding; Bristol-Myers-Squibb: Consultancy, Honoraria; Roche, Celgene: Honoraria, Research Funding.


2004 ◽  
Vol 91 (1) ◽  
pp. 81-90 ◽  
Author(s):  
Mi Kyung Kim ◽  
Satoshi Sasaki ◽  
Shizuka Sasazuki ◽  
Shunji Okubo ◽  
Masato Hayashi ◽  
...  

Antioxidant vitamins have been reported to be associated with an improvement in blood lipid profiles, but results are not consistent. The present study was designed to determine whether long-term vitamin C supplementation could alter serum lipid concentrations in subjects who completed a 5-year population-based double-blind intervention trial. A total of 439 Japanese subjects with atrophic gastritis initially participated in the trial using vitamin C and β-carotene to prevent gastric cancer. Before and upon early termination of β-carotene supplementation, 134 subjects dropped out of the trial; finally, 161 subjects assigned to the high-dose group (500 mg vitamin C/d) and 144 subjects assigned to the low-dose group (50 mg vitamin C/d) were studied. No favourable effect of vitamin C supplementation on serum concentrations of total cholesterol, HDL- and LDL-cholesterol, and triacylglycerol was observed, although high-dose vitamin C supplementation increased serum vitamin C concentrations substantially. Among women, the mean change in serum triacylglycerol decreased (−0·12 mmol/l, 95 % CI −0·32, 0·09) in the high-dose group, but increased (+0·12 mmol/l, 95 % CI 0·03, 0·22) in the low-dose group. In addition, the mean change in serum triacylglycerol among women with hypertriacylglycerolaemia was statistically significant (−1·21, 95 % CI −2·38, −0·05) after high-dose vitamin C supplementation. The 5-year vitamin C supplementation had no markedly favourable effects on the serum lipid and lipoprotein profile. However, our present results do not preclude the possibility that vitamin C supplementation may decrease triacylglycerol concentrations among women with hypertriacylglycerolaemia.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
J. A. Tumlin ◽  
C. M. Galphin ◽  
B. H. Rovin

Background and Objective.Adrenocorticotropic hormone (ACTH) is able to reduce proteinuria in nondiabetic glomerulopathies through activation of melanocortin receptors (MCR) expressed in the podocyte. To determine the efficacy of ACTH, we conducted a randomized, open-label pilot trial of ACTH gel in patients with advanced diabetic nephropathy.Study Design.Twenty-three (23) patients with diabetic nephropathy were randomized to daily subcutaneous (SQ) injections of 16 or 32 units of ACTH gel for six months.Outcome.The primary endpoint was the percentage of patients achieving a complete remission (<300 mg/24 hours) within 6 months. Exploratory endpoints included the percentage of partial (50% reduction) remissions, changes in Cr, and urinary cytokine markers.Results.After 6 months of ACTH gel therapy, 8 of 14 (57%) patients achieved a complete (n=1) or partial (n=7) remission. In the low-dose ACTH gel group (16 units), urinary protein fell from6709+953to2224+489 mg/24 hrs (P<0.001). In contrast, 2 of 6 patients in the 32-unit group achieved partial remission, but aggregate proteinuria (5324+751to5154+853 mg/24 hours) did not change. Urinary VEGF increased from 388 to 1346 pg/mg urinary creatinine (P<0.02) in the low-dose group but remained unchanged in the high-dose group.Conclusion.ACTH gel stabilizes renal function and reduces urinary protein for up to 6 months after treatment. The ClinTrials.gov identifier isNCT01028287.


2018 ◽  
Vol 2 (S1) ◽  
pp. 5-6
Author(s):  
Julia D’Souza ◽  
Laith Sultan ◽  
Sean Carlin ◽  
Terence Gade ◽  
Stephen Hunt ◽  
...  

OBJECTIVES/SPECIFIC AIMS: Preliminary animal studies showed that low-intensity ultrasound (US) coincident with intravascularly administered microbubbles locally disrupts tumor vasculature. This study translates the novel therapy of antivascular ultrasound (AVUS) into an autochthonous model of hepatocellular carcinoma (HCC). The differential effects produced by AVUS at low and high doses are evaluated. METHODS/STUDY POPULATION: HCC was induced in 12 Wistar rats by ingestion of 0.01% diethylnitrosamine in drinking water for 12 weeks. Rats received AVUS treatment at low and high doses. Low dose group (n=6) received 1 W/cm2 US for 1 minute with 0.2 mL microbubbles injected IV. High dose group (n=6) received 2 W/cm2 for 2 minute with 0.7 mL microbubbles IV. Perfusion was measured before and after AVUS with contrast-enhanced ultrasound (CE-US) and power Doppler (PD-US). Peak enhancement (PE) and perfusion index (PI) were measured from each US mode. Histology after sacrifice or natural death was compared to pre/post US. Analysis of H&E and trichrome sections was evaluated for percent area of hemorrhage and findings of tissue injury and repair including inflammation, necrosis, and fibrosis. RESULTS/ANTICIPATED RESULTS: After high dose AVUS, PE, and PI of CE-US decreased from baseline by an average of 33.3% and 29.7%, respectively. Histology showed extensive tissue injury (hemorrhage, necrosis, fibrosis) in 58% of tumor cross-sectional area. Conversely, low dose AVUS increased PE and PI of CE-US by an average of 39.3% and 67.8%, respectively. Histology showed smaller areas of microhemorrhage Versus large pools of hemorrhage (only 17% area). PD-US changes were similar to CE-US. DISCUSSION/SIGNIFICANCE OF IMPACT: In summary, the opposing effects of AVUS observed at 2 doses allows for multiple roles in tumor therapy. Enhanced perfusion at a low dose may improve drug delivery or radiation therapy. Whereas, vascular disruption at high doses of AVUS may allow noninvasive ischemic therapy. Furthermore, AVUS is ripe for translation given the use its component parts clinically: low-intensity long-tone burst for physiotherapy and microbubbles as an US contrast agent. Thus, AVUS should be evaluated for translation of its differential effects into noninvasive therapies for HCC and other tumors.


Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 555 ◽  
Author(s):  
Katarzyna Palus ◽  
Michał Bulc ◽  
Jarosław Całka

Acrylamide is found in food products manufactured with high-temperature processing, and exposure to acrylamide contained in food products may cause a potential risk to human health. The aim of this investigation was to demonstrate the changes in the population of CART-, nNOS-, and VAChT-immunoreactive enteric neurons in the porcine stomach in response to supplementation of low and high acrylamide doses. The study was carried out with 15 Danish landrace gilts divided into three experimental groups: the control group—animals were administered empty gelatine capsules; the low-dose group—animals were administrated a tolerable daily intake (TDI) dose (0.5 µg/kg of body weight (b.w.)/day) of acrylamide capsules, and the high-dose group—animals were administrated high-dose (ten times higher than TDI: 5 µg/kg b.w./day) acrylamide capsules for 28 days. Using the double immunofluorescence staining method, it was established that supplementation with low and high doses of acrylamide resulted in alterations of the porcine stomach neuron phenotype, which was reflected in an increased number of CART-, VAChT-, and nNOS-immunoreactive neurons. These changes were accompanied by an increased density of CART-, VAChT-, and nNOS-positive fibres. The results suggest that the enteric nervous system plays an important role in protecting the gastrointestinal tract during acrylamide intoxication.


QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Walid Said Ibrahim ◽  
Mohamed Moustafa Farouk ◽  
Mazen Tawfik ◽  
Sherif Samir Elzahwy

Abstract Background Concern has always existed that statins might impair testosterone production either by reducing availability of its preferred substrate, that is, locally produced de novo cholesterol in the gonads and elsewhere, or by inhibiting steps in the steroidogenesis process, but this concern has been considered of little clinical significance. Objective To demonstrate the impact of high doses of statins on testosterone level in ischemic heart disease patients and to compare it with the impact of low doses of statins. Patients and Methods This study was approved by Ain Shams University. 90 candidates were randomly enrolled in the study divided into two groups, high dose group consisting of 45 patients and Low dose group including 45 patients. All patients were recruited from International Medical Center in Cairo, they were selected randomly from the outpatient clinic from the cardiology department. Results In our study there were a significant reduction in total cholesterol, LDL and TGs in both low dose and high dose groups, but the effect on testosterone was quite different between them, the reduction in testosterone was about 33% from the baseline in the high dose group while in the low dose there was no significant reduction in the testosterone level. Conclusion This study shows that statins reduce testosterone level. This finding does not demonstrate that androgens mediate any health effect of statins, but raises the question as to whether testosterone modulation plays a role in statins' effects on health, particularly among men where testosterone is an important hormone.


1984 ◽  
Vol 52 (03) ◽  
pp. 276-280 ◽  
Author(s):  
Sam Schulman ◽  
Dieter Lockner ◽  
Kurt Bergström ◽  
Margareta Blombäck

SummaryIn order to investigate whether a more intensive initial oral anticoagulation still would be safe and effective, we performed a prospective randomized study in patients with deep vein thrombosis. They received either the conventional regimen of oral anticoagulation (“low-dose”) and heparin or a more intense oral anticoagulation (“high-dose”) with a shorter period of heparin treatment.In the first part of the study 129 patients were randomized. The “low-dose” group reached a stable therapeutic prothrombin complex (PT)-level after 4.3 and the “high-dose” group after 3.3 days. Heparin was discontinued after 6.0 and 5.0 days respectively. There was no difference in significant hemorrhage between the groups, and no clinical signs of progression of the thrombosis.In the second part of the study another 40 patients were randomized, followed with coagulation factor II, VII, IX and X and with repeated venograms. A stable therapeutic PT-level was achieved after 4.4 (“low-dose”) and 3.7 (“high-dose”) days, and heparin was discontinued after 5.4 and 4.4 days respectively. There were no clinical hemorrhages, the activity of the coagulation factors had dropped to the same level in both groups at the time when heparin was discontinued and no thromboembolic complications occurred.Our oral anticoagulation regimen with heparin treatment for an average of 4.4-5 days seems safe and reduces in-patient costs.


2020 ◽  
Vol 22 (1) ◽  
pp. 176
Author(s):  
Toshiaki Iba ◽  
Jerrold H. Levy ◽  
Koichiro Aihara ◽  
Katsuhiko Kadota ◽  
Hiroshi Tanaka ◽  
...  

(1) Background: The endothelial glycocalyx is a primary target during the early phase of sepsis. We previously reported a newly developed recombinant non-fucosylated antithrombin has protective effects in vitro. We further evaluated the effects of this recombinant antithrombin on the glycocalyx damage in an animal model of sepsis. (2) Methods: Following endotoxin injection, in Wistar rats, circulating levels of hyaluronan, syndecan-1 and other biomarkers were evaluated in low-dose or high-dose recombinant antithrombin-treated animals and a control group (n = 7 per group). Leukocyte adhesion and blood flow were evaluated with intravital microscopy. The glycocalyx was also examined using side-stream dark-field imaging. (3) Results: The activation of coagulation was inhibited by recombinant antithrombin, leukocyte adhesion was significantly decreased, and flow was better maintained in the high-dose group (both p < 0.05). Circulating levels of syndecan-1 (p < 0.01, high-dose group) and hyaluronan (p < 0.05, low-dose group; p < 0.01, high-dose group) were significantly reduced by recombinant antithrombin treatment. Increases in lactate and decreases in albumin levels were significantly attenuated in the high-dose group (p < 0.05, respectively). The glycocalyx thickness was reduced over time in control animals, but the derangement was attenuated and microvascular perfusion was better maintained in the high-dose group recombinant antithrombin group (p < 0.05). (4) Conclusions: Recombinant antithrombin maintained vascular integrity and the microcirculation by preserving the glycocalyx in this sepsis model, effects that were more prominent with high-dose therapy.


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