Acute and chronic hypopituitarism is associated with severe envenoming by the Burmese Russell's viper. We have demonstrated that in vitro, Burmese Russell's viper venom (0.1-10 micrograms/ml) causes a dose-dependent release of GH, TSH and ACTH from dispersed rat anterior pituitary cells in culture. At 10 micrograms/ml, venom causes a significant increase in the release of GH (344%, P less than 0.001), TSH (168%, P less than 0.005) and ACTH (greater than 700%, P less than 0.001). We have also shown that the component (or components) responsible for this stimulatory effect is stable to heat (60 degrees C, 1 h) and mild trypsinization. Repeated addition of venom (1 microgram/ml) to pituitary cells in a perifusion column system demonstrated attenuation of GH release. This reduced response was not due to depletion of the GH pool since the pituitary cells were subsequently able to respond to both GH-releasing factor (GRF) stimulation and KCl depolarization. Somatostatin in a dose which abolished GRF-stimulated GH release failed to affect venom-stimulated GH release, implying that venom acts in a cyclic AMP-independent manner. We conclude that Burmese Russell's viper venom has direct effects on pituitary hormone release in vitro. Whether these effects contribute to its known actions in vivo on the function of the pituitary remains to be established.
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http://dx.doi.org/10.1677/joe.0.1220489 | DOI Listing |
J Adolesc
August 2023
Department of Human Development and Family Sciences, Population Research Center, The University of Texas at Austin, Austin, Texas, USA.
Introduction: The "model minority" stereotype disguises heterogeneity among Asian American youth, many of whom are harmed by policies and attitudes that assume this population to be uniformly high achieving and "problem free." The current study uses an intersectional lens to disaggregate this population by ethnicity and sexual orientation subgroups to demonstrate differences in academic performance and substance use behavior among Asian American youth. This study also investigates the extent to which racial/ethnicity and sexual orientation-based bullying may explain such links.
View Article and Find Full Text PDFGastroenterology
June 2021
Division of Gastroenterology and Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy; European Reference Network on Hepatological Diseases, San Gerardo Hospital, Monza, Italy. Electronic address:
Background & Aims: Genome-wide association studies in primary biliary cholangitis (PBC) have failed to find X chromosome (chrX) variants associated with the disease. Here, we specifically explore the chrX contribution to PBC, a sexually dimorphic complex autoimmune disease.
Methods: We performed a chrX-wide association study, including genotype data from 5 genome-wide association studies (from Italy, United Kingdom, Canada, China, and Japan; 5244 case patients and 11,875 control individuals).
J Infect Dis
July 2017
Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymatic disorder in humans and appears to be protective against falciparum severe malaria. Controversially, it is also thought that Plasmodium vivax has driven the recent selection of G6PD alleles. We use an experimental approach to determine whether G6PD-MahidolG487A variant, a widespread cause of severe G6PD deficiency in Southeast Asia, provides a barrier against vivax malaria.
View Article and Find Full Text PDFBMC Evol Biol
April 2017
Department of Geology, Western Illinois University, Tillman Hall 113, 1 University Circle, Macomb, IL, 61455, USA.
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