The link between reproduction and environmental signals is poorly understood at the physiological, genetic and molecular levels. We describe a mutant strain of Drosophila virilis that has altered responses to heat stress. Heat stress in wild-type females results in oocyte maturation delays, degradation of early vitellogenic egg chambers, inhibition of yolk protein gene expression in follicle cells and accumulation of mature oocytes. The mutant females have increased levels of ecdysteroids and decreased juvenile hormone degradation, and show all of the heat-stress-induced reproductive effects observed in wild-type flies, without exposure to heat stress. During oogenesis in mutant females following heat stress there is an increase in early vitellogenic oocyte degradation and some degradation of late egg chambers. 20-Hydroxyecdysone levels, but not juvenile hormone degradation, change following heat stress in mutant females.
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http://dx.doi.org/10.1046/j.1365-2583.2003.00424.x | DOI Listing |
Electromagn Biol Med
January 2025
Department of Mathematics, University of Gour Banga, Malda, India.
In cardiovascular research, electromagnetic fields generated by Riga plates are utilized to study or manipulate blood flow dynamics, which is particularly crucial in developing treatments for conditions such as arterial plaque deposition and understanding blood behavior under varied flow conditions. This research predicts the flow patterns of blood enhanced with gold and maghemite nanoparticles (gold-maghemite/blood) in an electromagnetic microchannel influenced by Riga plates with a temperature gradient that decays exponentially, under sudden changes in pressure gradient. The flow modeling includes key physical influences like radiation heat emission and Darcy drag forces in porous media, with the flow mathematically represented through unsteady partial differential equations solved using the Laplace transform (LT) method.
View Article and Find Full Text PDFAppl Environ Microbiol
January 2025
Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, China.
Unlabelled: High temperature is an unavoidable environmental stress that generally exerts detrimental effects on organisms and has widespread effects on metabolism. Spermidine is an important member of the polyamines family and is involved in a range of abiotic stress responses in plants. Mitochondria play an essential role in cellular homeostasis and are key components of the stress response.
View Article and Find Full Text PDFFront Immunol
January 2025
Poultry Institute, Shandong Academy of Agricultural Science, Jinan, Shandong, China.
Heat-stress-induced oxidative and inflammatory responses were important factors contributing to chicken intestinal damage. The purpose of this study was based on the antioxidant and anti-inflammatory activities of Physalis Calyx seu Fructus (Jin Deng Long, JDL) to investigate its efficacy and mechanism in relieving chicken heat stress damage. Primary chicken embryo duodenum cells and 90 30-day-old specific-pathogen-free chicken were randomly divided into control and JDL groups to establish heat stress models and .
View Article and Find Full Text PDFPublic Health Pract (Oxf)
June 2025
Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, ON, Canada.
Background: With the growing threat posed by extreme heat, heat-health messaging communicated by public health authorities is critical for raising community awareness and action. This study sought to (i) identify what heat-health content is shared online by Canadian public health authorities and (ii) analyse the material to develop an understanding of the content included within the resources.
Study Design: Qualitative content analysis.
JDS Commun
January 2025
School of Animal Sciences, Virginia Tech, Blacksburg, VA 24061.
Prolonged exposure to high environmental temperatures results in an accumulated heat load that induces a heat stress (HS) response in dairy cattle. Heat stress compromises dairy farm profitability by reducing milk yield, altering milk composition, and hindering reproductive performance. The ability to alternate between carbohydrate and lipid sources for energy production is termed metabolic flexibility (Met Flex).
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