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61.
Translated fromBuylleten' Eksperimental'noi Biologii i Meditsiny, Vol. 115, No. 1, pp. 21–23, January, 1993 相似文献
62.
目的探讨瞬时受体电位香草素受体4型通道蛋白(TRPV4)抑制剂HC067047对小鼠膝骨关节炎软骨组织的影响。 方法将30只小鼠均分为假手术组、模型组、HC067047组。假手术组仅切开右侧膝关节髌韧带内侧皮肤,不予处理膝关节囊内结构;模型组、HC067047组手术切除小鼠板股韧带及内侧半月板前角以构建膝骨关节炎,分别用生理盐水、HC067047每天10 mg/kg灌胃。qRT-PCR检测各组小鼠软骨组织中TRPV4 mRNA表达水平。番红固绿染色评估关节软骨受损程度,HE染色分析膝关节软骨下骨的骨量变化。Western blotting检测各组软骨组织中细胞焦亡标志蛋白TRPV4、Caspase-1、核苷酸结合寡聚化结构域样受体家族热蛋白结构域蛋白3(NLRP3)、凋亡相关斑点样蛋白(ASC)、GSDMD-N蛋白水平;ELISA、Western blotting分别检测血清、软骨组织中炎症因子水平。 结果与假手术组比较,模型组TRPV4、NLRP3、ASC、Caspase-1、GSDMD-N、IL-1β、IL-18水平显著升高(P<0.05)。与模型组比较,HC067047组NLRP3、ASC、Caspase-1、GSDMD-N、IL-1β、IL-18水平显著降低(P<0.05)。HC067047能明显改善关节软骨形态及降低骨关节炎受损程度,并能维持软骨下骨的骨量。 结论TRPV4抑制剂HC067047能抑制软骨组织细胞焦亡,改善膝骨关节炎小鼠关节软骨的退变。 相似文献
63.
One hundred forty-nine specimens were tested in a LightCycler nested multiplex polymerase chain reaction (LCnmPCR) for Herpes simplex virus (HSV)1, HSV2, and VZV. Eighty-one were from genitourinary medicine (GUM) patients and the other 68 specimens were from other patients with skin lesions. The results were compared to a conventional multiplex nested PCR (nmPCR) using agarose gel electrophoresis. Twenty-five specimens were positive in both assays for HSV1 and 29 were positive for VZV. For HSV2 there were 27 positive in the LCnmPCR and 26 positive in the nmPCR assay. The melting temperatures (Tms) of each target were different with a mean of 84.75 degrees C for HSV1, 88.57 degrees C for HSV2, and 83.62 degrees C for VZV. The melting curves of positive specimens directly overlaid the melting curves of the positive controls in the assay. The LCnmPCR assay is a convenient alternative to conventional PCR using agarose gel electrophoresis. It improves specimen turnaround time by eliminating the need for gel electrophoresis, transillumination, and gel photography. It also shows increased sensitivity for HSV2 over our standard assay. This LCnmPCR reduces further the possibility of amplicon contamination with nested PCR protocols. 相似文献
64.
Motoko Yanase Hideto Tanaka Teruo Nakayama 《European journal of applied physiology》1989,58(4):446-451
Summary In female rats, rectal temperature (T
re), tail vasomotor response, oxygen uptake
, and carbon dioxide production
were measured in proestrus and estrus stages during treadmill running at two different speeds at an ambient temperature (T
a) of 24° C. Experiments were performed at 2.00–6.00 a.m., when the difference inT
re was greatest between the two stages;T
re at rest in the estrus stage was 0.54° C higher than in the proestrus stage. In a mild warm environment, thresholdT
re for a rise in tail skin temperature (T
tail) was also higher in the estrus stage than in the proestrus stage. In contrast, no difference was seen in the thresholdT
re and steady stateT
re at the end of exercise between proestrus and estrus stages. These values were higher at the higher work intensity.
was also similar between the two stages, except in the second 5 min after the beginning of exercise, when
was greater andT
re rose more steeply in the proestrus stage. These data indicate that deep body temperature during exercise is regulated at a certain level depending on the work intensity and is not influenced by the estrus cycle.This study was supported in part by a Grant-in Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan (Grant No. 62480114) 相似文献
65.
Weller A Leguisamo AC Towns L Ramboz S Bagiella E Hofer M Hen R Brunner D 《Developmental psychobiology》2003,42(2):194-205
The influence of the pre- and postweaning maternal environment on the offspring's phenotype was examined in 5-HT1A and 5-HT1B receptor knockout mice (KO1A and KO1B, respectively). We have previously shown that, when born to and raised by homozygous dams of the same genotype, adult KO1A are more anxious than wild-type (WT) mice, and adult KO1B are hyperactive and slightly less anxious than WT mice. We extend our studies here to the behavioral results of the offspring's own genotype, when the dam's genotype is constant, and the effects of the dam's genotype when the offspring's genotype is constant. In Experiments 1 and 2, KO1A-/- pups produced less ultrasonic vocalizations (USV) than controls in an isolation test on postnatal Day 7 when born to and reared by KO1A dams, either -/- or +/-. Heterozygous F1 pups reared by KO1A-/- dams produced more USV and were less anxious in the plus-maze at 2 to 3 months of age than F1 pups born to and reared by WT dams (Experiment 3). F1 pups reared by KO1B-/- dams produced less USV and were more anxious in the plus-maze than F1 pups reared by WT dams (Experiment 4). The results support a role for maternal effects that may comprise direct effects such as the dam's behavior and nutritional care of the pup, and possibly more complex indirect effects through the establishment of idiosyncratic dam-pup dyadic interactions. We recommend that breeding techniques that rely on same genotype (mutant-mutant or WT-WT) breeding pairs not be used to generate offspring when the focus of research is the study of gene function, but rather when familial effects need to be studied. 相似文献
66.
Summary The data collected by the authors in four experimental series have been analysed together with data from the literature, to
study the relationship between mean skin temperature and climatic parameters, subject metabolic rate and clothing insulation.
The subjects involved in the various studies were young male subjects, unacclimatized to heat. The range of conditions examined
involved mean skin temperatures between 33‡ C and 38‡ C, air temperatures (Ta) between 23‡ C and 50‡ C, ambient water vapour pressures (Pa) between 1 and 4.8 kPa, air velocities (Va) between 0.2 and 0.9 m · s−1, metabolic rates (M) between 50 and 270 W · m−2, and Clo values between 0.1 and 0.6. In 95% of the data, mean radiant temperature was within ±3‡ C of air temperature. Based
on 190 data averaged over individual values, the following equation was derived by a multiple linear regression technique:
ˉTsk=30.0+0.138Ta+0.254Pa−0.57Va+1.28 · 10−3 M−0.553 Clo. This equation was used to predict mean skin temperature from 629 individual data. The difference between observed
and predicted values was within ±0.6‡ C in 70% of the cases and within ±1‡ C in 90% of the cases. It is concluded that the
proposed formula may be used to predict mean skin temperature with satisfactory accuracy in nude to lightly clad subjects
exposed to warm ambient conditions with no significant radiant heat load. 相似文献
67.
Levente Kaps Ferenc Obl Jr. Mark R. Opp Lars Johannsen James M. Krueger 《Physiology & behavior》1991,50(6):1241-1244
Cholecystokinin (CCK) reduces food intake and promotes non-rapid-eye-movement sleep (NREMS) in rats. The purpose of present experiments was to determine if CCK is somnogenic in rabbits; another species in which CCK suppresses feeding. White New Zealand rabbits were treated intracerebroventricularly (ICV; 0.05, 0.5 and 2 μg) or intraperitoneally (IP; 2.5, 10 and 40 μg/kg) with CCK or saline, and sleep-wake activity and brain temperature (Tbr) were recorded for 6 h. Injections of 10 and 40 μg/kg CCK IP elicited a decrease in wakefulness and an increase in NREMS during the first hour postinjection. The hypnogenic effects were accompanied by a decrease in Tbr. After the IP injection of a lower dose (2.5 μg/kg) a slight, nonsignificant increase in NREMS during the first hour postinjection was followed by a decrease in NREMS. ICV injections of CCK had relatively small inhibitory effects on sleep. We conclude that circulating, hormone CCK might be a hypnogenic signal with a peripheral site of action. 相似文献
68.
The effect of temperature and sex on spatial distribution ofDrosophila melanogaster adults was studied in a specially designed apparatus. It was observed that individuals tend to aggregate in sections of the sphere independently of sex and temperature. Nevertheless, decrease in temperature increase aggregation. The mobility of both males and females indicates a megative geotactic tendency. 相似文献
69.
Satoshi Takahashi Dawn D. Tooley Levente Kapás Jidong Fang Jerome M. Seyer James M. Krueger 《Pflügers Archiv : European journal of physiology》1995,431(2):155-160
Tumor necrosis factor (TNF) is a cytokine that possesses many biological activities, including enhancement of non-rapid-eye-movement sleep (NREMS). The role of endogenous TNF in the regulation of spontaneous sleep is unknown. If TNF is involved in sleep regulation, then reduction of endogenous TNF should suppress spontaneous sleep. A soluble TNF-binding protein I (TNF-BP I) and a synthetic fragment of TNF-BP I, TNF-R-(159–178), that contains the biologically active region of TNF-BP I, were used. These substances bind TNF and possess TNF-inhibitory activity; their effects on rabbit sleep after intracerebroventricular injection were determined across a 6-h recording period. Two doses of TNF-BP I (0.05 g and 0.5 g) were administered; the higher dose of TNF-BP I significantly decreased NREMS. Four doses of TNF-R-(159–178) (0.25 g, 2.5 g, 25 g and 50 g) were used. The 25 g and 50 g doses significantly suppressed NREMS. The highest dose (50 g) also decreased REM sleep. These results are consistent with the hypothesis that endogenous brain TNF is involved in the regulation of normal sleep. 相似文献
70.
Yoshimitsu Inoue Mikio Nakao Syozo Okudaira Hiroyuki Ueda Tsutomu Araki 《European journal of applied physiology》1995,70(1):6-12
Eight older (60–65 years) and six younger (20–25 years) men were exposed to a standard heat stress for 60 min in summer, autumn, winter, and spring. The test consisted of placing the lower legs and feet in a 42°C water bath while sitting in constant environmental conditions (30°C and 45% relative humidity). The increase of rectal temperature (T
re) was significantly greater (P < 0.05) in autumn, winter, and spring than in summer for the older group, but significantly greater only in winter than in summer for the younger group (P < 0.05). The T
re was greater for the older group in all seasons, but of significance only in autumn and spring (P < 0.01). There were no significant season-related differences for metabolic heat production (m) and mean skin temperature (
sk) during the heat test in the respective groups, although the m and
sk were lower for the older group in all seasons (P < 0.01). In the older group total body sweating rate (msw) divided by T
re (total msw/T
re) decreased from summer to winter (P < 0.02) and did not differ between winter and spring, whereas total msw/T
re in the younger group increased in spring after decreasing from autumn to winter (P < 0.03). The variations of the value, local sweating rate on the back and thigh divided by T
re (back msw/T
re and thigh msw/T
re), were similar to those of the total msw/T
re in each group, except for back msw/T
re in the younger group, which did not increase from winter to spring. The total msw/T
re, back msw/T
re and thigh msw/T
re were significantly less for the older group in summer, autumn and spring (P < 0.05). The range of seasonal variations was significantly less for the older group (P < 0.001). The results indicated that, compared with younger men in older men, the enhancement of sweating function toward summer occurred later and its reduction toward winter occurred earlier despite a smaller range of seasonal variation and that older men had a somewhat lesser capability to maintainT
re when challenged by heat stress in all seasons. 相似文献