Role Of Temperature In Regulation Research Articles

Role of temperature in regulation of the life cycle of temperate fish

The review provides information on adaptive responses of fish metabolic processes in response to temperature reduction of habitat, including the direction of adjustment of energy metabolism and mechanisms to improve the adaptive capacity and reparative capacity of tissues in response to lower temperatures. It presents data on the effect of temperature on the reproductive function of fish and fish development processes in the early stages of ontogeny.

Abstract 575: A novel warming strategy for improving neutrophil recovery following total body irradiation

Abstract Total body irradiation (TBI) exposure damages not only the hematopoietic compartment but also at least two other important immunological barriers to infection: the gut mucosa and the skin. This leaves those exposed to sufficient doses of radiation highly susceptible to infection. In order to prevent illness or death from microbial invaders, new strategies are needed that can safely and rapidly boost leukocyte numbers. We hypothesized that mildly elevating core temperature, which we and others have shown previously to alter leukocyte numbers and migration patterns, following a non-myeloablative dose of TBI, will enhance immune reconstitution through a thermally sensitive, cytokine driven bone marrow release of granulocytes to the peripheral blood. This hypothesis was generated from the following initial observations: C57BL/6 mice were given TBI (3Gy) followed 2 hours later by a mild heating (where core body temperature was elevated to 39.5°C). In mice that were heated following TBI, a significant increase in recovery rate of peripheral blood granulocytes was observed by day 8 compared to mice that received radiation alone or heating alone. In addition, G-CSF concentration was increased two fold in the serum of radiated/heated mice correlating with the increased granulocyte recovery. G-CSF production was driven by IL-17 production in the intestine seen only when radiation was followed by heat treatment. IL-17 was later confirmed to be necessary for the thermal enhancement of neutrophil recovery when the effect of heating after radiation was lost in the IL-17R knockout mouse model. Flow analysis of the bone marrow from wild type mice revealed comparable percentages of hematopoietic stem cells in the control (63.3±2.8% of LSK were CD34-) and the radiation/heat-treated groups (62.0±1.2% of LSK were CD34-); however, there was a significantly lower percentage of hematopoietic stem cells in the bone marrow of the radiation-alone group (43.4±1.7%; p<0.003). Flow analysis revealed that increasing core body temperature following total body irradiation increased the overall percentage of granulocyte-macrophage progenitors when compared to control and radiation-alone groups (12.4±2.1% vs. 6.7±1.3% and 7.67±2.1%; p<0.025). This increase in progenitor percentages in radiated/heated mice is associated with an increase in overall number of CFUs (45±3.8) when compared to radiation alone (32±4.3). These data reveal a previously unexplored role of body temperature in regulation of hematopoiesis and marrow output following stress and may help in the development of novel, clinically applicable strategies to ameliorate the effects of TBI. Supported by NIH P01 CA94075 and R01 CA71599. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 575. doi:10.1158/1538-7445.AM2011-575

Role of temperature in regulation of spermatogenesis and the use of heating as a method for contraception

Role of temperature in regulation of spermatogenesis and the use of heating as a method for contraception

Role of Temperature in Regulation of Spermatogenesis and the Use of Heating as a Method for Contraception

A large body of research confirms the vulnerable nature of spermatogenesis to relatively small increases in testicular temperature. Other physical properties of electromagnetic and ultrasound waves have additive or synergistic effects to those of heat and allow disruption of spermatogenic processes at minimal temperature elevations. In addition there is a rebound in sperm count following heat-induced suppression of spermatogenesis. These findings suggest the theoretical viability of testicular heating as a reversible method of male contraception in humans. However before heating techniques can be used for male fertility control several questions remain to be investigated. The lowest effective doses and the lowest frequency of application of each method of testicular heating necessary for inducing and maintaining a reliable infertile state must be established. It must be determined whether long-term exposure leads to permanent damage or compromise of testicular elements or functions and whether exposure to simple heat electromagnetic waves or ultrasound induces significant changes in the biological constituents of human semen. Also unclear is the exact mutagenic potential of thermal agents on the human gonads. Another research question is whether scrotal warm sensory input rises during testicular heating to a level that is sufficient to alter body core temperature. Rapidly advancing knowledge of biologic constituents of human semen and the increasingly available detection methods of these constituents will enhance research in these areas. It is through such research that the safety efficacy and applicability of thermal manipulation of spermatogenesis as a method of male contraception will be established or refuted.

Role of temperature in regulation of spermatogenesis and the use of heating as a method for contraception

A large body of research confirms the vulnerable nature of spermatogenesis to relatively small increases in testicular temperature. Other physical properties of electromagnetic and ultrasound waves have additive or synergistic effects to those of heat and allow disruption of spermatogenic processes at minimal temperature elevations. In addition, there is a rebound in sperm count following heat-induced suppression of spermatogenesis. These findings suggest the theoretical viability of testicular heating as a reversible method of male contraception in humans. However, before heating techniques can be used for male fertility control, several questions remain to be investigated. The lowest effective doses and the lowest frequency of application of each method of testicular heating necessary for inducing and maintaining a reliable infertile state must be established. It must be determined whether long-term exposure leads to permanent damage or compromise of testicular elements or functions, and whether exposure to simple heat, electromagnetic waves, or ultrasound induces significant changes in the biological constituents of human semen. Also unclear is the exact mutagenic potential of thermal agents on the human gonads. Another research question is whether scrotal warm sensory input rises during testicular heating to a level that is sufficient to alter body core temperature. Rapidly advancing knowledge of biologic constituents of human semen and the increasingly available detection methods of these constituents will enhance research in these areas. It is through such research that the safety, efficacy, and applicability of thermal manipulation of spermatogenesis as a method of male contraception will be established or refuted.