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31.
The effect of the growth state of a cell on the ability of hyperthermia to induce the synthesis of heat shock proteins (HSPs) was studied in resting and concanavalin A (ConA)-stimulated lymphocytes. Hyperthermia induced the synthesis of hsp 110, hsp 90, hsc 70, and hsp 70 in both resting and ConA-stimulated lymhocytes, and ConA-treatment induced the synthesis of the hsp 90 and hsc 70 at normal temperature. The induction of the synthesis of hsp 110 and hsp 70 by hyperthermia was 3- to 6-fold higher for lymphocytes cultured with ConA for 12 and 24 h than in non-stimulated lymphocytes. Thus, lymphocytes induced to undergo proliferation showed a greater response to hyperthermia than resting lymphocytes. 相似文献
32.
热休克蛋白60对小鼠树突状细胞功能影响体外研究 总被引:1,自引:0,他引:1
目的:探讨动脉粥样硬化中重要炎性物质——热休克蛋白60(HSP60)体外对小鼠树突状细胞(mDC)功能影响.方法:小鼠骨髓提取DC,体外培养成熟后与两种浓度mHSP60孵育,动态观察DC突起改变;流式细胞仪检测孵育前后mDC表面标志改变;MLR测定孵育前后mDC刺激功能变化;ELISA法测定MLR上清液中细胞因子浓度.结果:孵育后,mDC突起增加明显;CD11c^+、CD80及CD86表型显著增加;淋巴细胞刺激功能明显增强;分泌细胞因子IL-12、IFN-γ增加(P<0.01)而IL-4增加不明显(P>0.05),IFN-γ/IL-4比值升高.结论:mHSP60体外可以促进mDC功能,作用呈剂量依赖性. 相似文献
33.
34.
Eva Müller Wolfgang Neuhofer Akihiro Ohno Silvia Rucker Klaus Thurau Franz-X. Beck 《Pflügers Archiv : European journal of physiology》1996,431(4):608-617
The distribution of heat shock proteins (HSP) HSP60, HSP73, HSP72 and HSP25 in the isoosmotic cortex and the hyperosmotic medulla of the rat kidney was investigated using Western blot analysis and immunohistochemistry. HSP73 was homogeneously distributed throughout the whole kidney. The level of HSP60 was high in the renal cortex and low in the medulla. HSP25 and HSP72 were present in large amounts in the medulla. Only low levels of HSP25 and almost undetectable amounts of HSP72 were found in the cortex. HSP25 exists in one nonphosphorylated and several phosphorylated isoforms. Western blot analysis preceded by isoelectric focussing showed that HSP25 predominates in its nonphosphorylated form in the outer medulla but in its phosphorylated form in cortex and inner medulla. Although this intrarenal distribution pattern was not changed during prolonged anaesthesia (thiobutabarbital sodium), a shift from the nonphosphorylated to the phosphorylated isoforms of HSP25 occurred in the medulla. The characteristic intrarenal distribution of the constitutively expressed HSPs (HSP73, HSP60, HSP25) may reflect different states of metabolic activity in the isoosmotic (cortex) and hyperosmotic (medulla) zones of the kidney. The high content of inducible HSP72 in the medulla most likely is a consequence of the osmotic stress imposed upon the cells by the high urea and salt concentrations in the hyperosmotic medullary environment. 相似文献
35.
The effect of physical training on the cutaneous vascular response during transient exercise load is unclear. We determined the phase response and amplitude response of cutaneous vascular conductance (CVC) in the hand during sinusoidal exercise in endurance exercise-trained and untrained subjects. Subjects exercised on a cycle ergometer with a sinusoidal load for 32 min. The load variation ranged from 10% [23 (1) W in the trained group, 19 (1) W in the untrained group] to 60% [137 (4) W, 114 (6) W] of peak O2 uptake, and five different time periods (1, 2, 4, 8, and 16 min) were selected. Skin blood flow in the dorsal hand and palm were monitored by laser-Doppler flowmetry. CVC was evaluated from the ratio of blood flow to mean arterial pressure. During sinusoidal exercise, the amplitude of CVC was smaller in the dorsal hand than palm for shorter periods (1, 2, and 4 min) (P<0.05). The phase lag of CVC was smaller in the dorsal hand than palm for longer periods (8 and 16 min) (P<0.05). The amplitude response did not differ significantly between the two groups. The phase lag of CVC in the dorsal hand (P<0.05) and palm (P=0.06) was larger in the trained group than untrained group. These findings suggest that glabrous and nonglabrous skin vascular responses in the hand differ during transient exercise load, and physically trained subjects show a slower vascular response in the two skin areas to exercise stimulation than do untrained subjects. 相似文献
36.
Yukitoshi Aoyagi Tom M. McLellan Roy J. Shephard 《European journal of applied physiology》1995,71(2-3):197-206
Two methods of estimating body heat storage were compared under differing conditions of clothing, training, and acclimation to heat. Six male subjects underwent 8 weeks of physical training [60–80% of maximal aerobic power (
) for 30–45 min · day–, 3–4 days · week–1 at < 25 °C dry bulb (db)] followed by 6 consecutive days of heat acclimation (45–55%
for 60 min · day–1 at 40°C db, 30% relative humidity)]. Nine other male subjects underwent corresponding periods of control observation followed by heat acclimation. Before and after each treatment, subjects walked continuously on a treadmill (1.34 m · s–1, 2% grade) in a climatic chamber (40°C db, 30% relative humidity) for an average of 118 min (range 92–120 min) when wearing normal light combat clothing and for an average of 50 min (range 32–68 min) when wearing protective clothing resistant to nuclear, biological, and chemical agents. The heat storage was determined calorimetrically (by the balance of heat gains and losses) and thermometrically [by the conventional equations, using one or two set(s) of relative weightings for the rectal temperature (T
re) to mean skin temperature
sk of 4:1 and 4:1, 2:1 and 4:1, or 2:1 and 9:1 in thermoneutral and hot environments, respectively].
sk was calculated from 12-site measurements, weighted according to the regional distribution of body surface area and the first eigenvectors of principal component analysis. There were only minor differences (< 5%) between the heat storage values calculated by given weighting factors forT
re and
sk, whether the individual coefficients were derived from estimates of regional surface area or principal component methodologies. When wearing normal clothing, no significant differences were found between the two estimates of heat storage (calorimetry vs thermometry with an invariant relative weighting of 4:1) in any experimental condition, with one specific exception: when wearing protective clothing, thermometry underestimated the heat storage by 24–31%. This underestimation was attenuated by using two sets of relative weightings of 2: 1 and 4: 1 or 2: 1 and 9: 1. The results suggest that when subjects wearing protective clothing are transferred from thermoneutral to hot environments, the accuracy of thermometric estimates of heat storage can be improved by using two sets of weighting factors forT
re and
sk 相似文献
37.
L. C. Pele S. J. Thompson B. Kirkham R. P. H. Thompson J. J. Powell 《Inflammation research》2007,56(4):143-148
Objectives: The aims of this study were to determine, in peripheral blood mononuclear cells (PBMC), whether particulate antigen triggers
(i) an amplified cell proliferative response compared to soluble antigen and (ii) a dysfunctional response in cells derived
from patients with chronic inflammation and specifically in those with inflammatory bowel disease (IBD).
Subjects: Healthy volunteers (n = 17), inflammatory controls (n = 8) and patients with IBD (n = 17) were recruited from St Thomas’ and
Guys’ Hospital, London, UK.
Methods: Following optimisation of experimental conditions (0.1–10.0 μg/ml antigen), PBMC were stimulated with (i) 10.0 μg/ml recombinant
soluble heat shock protein 65 (hsp 65) and (ii) 1.0 and 10.0 μg/ml hsp 65 conjugated to microparticles (0.5 μm diameter).
PBMC proliferative responses were measured by 3H-Thymidine incorporation at day 5 and results compared between groups using unpaired t-test.
Results: Conjugation to microparticles of low dose hsp 65 significantly increased overall proliferative responses by 2–11 fold compared
to soluble antigen alone (p < 0.05). However, no specific PBMC proliferative dysregulation was noted in cells from subjects
with IBD.
Conclusions: Low dose antigen, in microparticulate form, leads to amplified cell proliferation in primary human cells, as showed previously
in cell lines and animal studies. However there is no abnormal proliferative response in cells from subjects with IBD.
Received 8 February 2006; returned for revision 7 March 2006; accepted by G. Wallace 25 October 2006 相似文献
38.
Mark J. Patterson James D. Cotter Nigel A. S. Taylor 《European journal of applied physiology》1995,71(5):416-423
Polycythaemia has been shown to improve physical performance, possibly due to increased arterial oxygen transport. Enhanced thermoregulatory function may also accompany this manipulation, since a greater proportion of the cardiac output becomes available for heat dissipation. We further examined this possibility in five trained men, who participated in three-phase heat stress trials (20 min rest, 20 min cycling at 30% peak power Wpeak and 20 min at 45% Wpeak at 38.3 (SEM 0.7)°C [relative humidity 41.4 (SEM 2.9)%]. Trials were performed during normocythaemia (control) and polycythaemia, obtained by reinfusion of autologous red blood cells and resulting in significant elevation of arterial oxygen transport. During the polycythaemic trials, the subjects demonstrated diminished thermal strain, as evidenced by a significant reduction in cardiac frequency (f
c: 12 beats · min–1 lower throughout the test;P < 0.05), and reduced auditory canal temperatures (T
ae) during the latter 20-min phase (P < 0.05). Forearm sweat onset was more rapid (363.0 compared to 1083.0 s;P < 0.05), and forearm sweat rate (.
msw) sensitivity was elevated from 1.80 to 2.91 · mg · cm–2 · min–1 · °C–1 (P < 0.05). Foreheadm
sw was depressed during the final 20 min, while forearmm
sw was greater during all test phases, averaging 0.94 and 1.20 mg · cm–2 · min–1, respectively, over the 60 min. Skin blood flows for the upper back, upper arm and forearm were reduced (P < 0.05). Polycythaemia enhanced thermoregulation, through an elevation in forearm sweat sensitivity and.m
sw, but not via increased cutaneous blood flow. These modifications occurred simultaneously with decreases inf
c andT
ae, resulting in greater thermal tolerance. 相似文献
39.
目的:探讨心理应激对海马CA3区神经元凋亡的影响,热休克蛋白70(Hsp70)对心理应激引起的海马CA3区神经元凋亡的保护作用。方法:建立心理应激、热应激(Heat Shock Pretreatment)、心理应激加热应激三种动物模型,利用免疫组化和TUNEL分别检测海马CA3区神经元在第1、2、3个月三个时间段的Hsp70表达和神经元凋亡水平。结果:有心理应激的各组动物海马凋亡神经元数高对照组(P<0·05),热应激加心理应激组凋亡神经元在2、3个月时较同时段心理应激组下降(P<0·05),但热应激组与对照组间差异没有显著性。有热应激各组Hsp70表达数高于无热应激的两组(P<0·01)。海马CA3区Hsp70表达水平与神经元调亡水平呈负相关(r=-0·26,P=0·03)。结论:热应激可促进海马Hsp70的表达,热休克蛋白70对心理应激导致的海马CA3区神经元损伤有保护作用。 相似文献
40.
Water intake and blood parameters of young (7-month) and old (23-month) male Brown Norway rats were assessed following a period of thermal dehydration. Rats of both ages were randomly assigned to one of three groups: (1) Unheated-blood sample, (2) Heated-blood sample, and (3) Heated-water intake. The colonic temperature of heated rats was raised at the rate of 0.05 degrees C/min for 1 h using an infrared heat lamp. Water intake was then measured over the following 2 h. The heating protocol resulted in a similar level of dehydration in both young and old rats; however, plasma osmolality and sodium concentration increased to a significant extent only in the young rats. Old rats drank significantly less water at all time points during the 2 h following the heat stress. While neither group replaced the water lost as a result of the thermal dehydration, the young rats did rehydrate to a greater extent. These results suggest that the diminished level of rehydration in aged rats, following a thermal dehydration, is due to an attenuated rise in plasma osmolality. 相似文献