Ultraviolet B (UVB) alters the expression of heat shock protein 70 (HSP70) in cultured fibroblast cells derived from human skin. However, the nature of the signal transduction pathway remains to be determined. Transforming growth factor-beta (TGF-beta) has a large variety of biological functions, including cell growth control, modulation of inflammation and immunoregulation. In this study, we examined whether TGF-beta is associated with the process of HSP70 expression induced by UVB irradiation. The constitutive expression of TGF-beta1 mRNA and HSP70 expression in human skin fibroblast cells were detected using reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. The results indicate that: (1) UVB irradiation stimulates HSP70 expression in a dose- and time-dependent manner, (2) constitutive expression of TGF-beta1 mRNA is detected after UVB irradiation, the level of which peaks at 4 h after 10 mJ cm-2 of UVB irradiation, (3) HSP70 expression is induced by TGF-beta1 without UVB irradiation, and (4) HSP70 expression induction with UVB irradiation is inhibited by preincubation of the cells with the anti-TGF-beta type II receptor antibody. Our results suggest that HSP70 expression induced by UVB involves the autocrine signalling of TGF-beta production.

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The local influence of three clothing materials i.e. silk, cotton and nylon, in (1) full or (2) partial skin contact or (3) at 3 mm from the skin, on sweat evaporation from the chest skin surface of human subjects was studied. The hygrometer-ventilated capsule method was used and sweating was induced at ambient thermoneutrality by a central heat load following lower-leg immersion in water at 43 degrees C. The presence of clothing delayed the rise in capsule relative humidity (CRH) induced by heat loading. During the first 6 min of heating, CRH rose more steeply with clothing that was in full skin contact than with clothing that had partial or no contact. The rate of decrease in CRH from 1 min to 6 min after heating was not influenced by the presence of clothing or by the different degrees of skin contact. The subsequent return of CRH to the pre-heating level was delayed most by cotton, less by silk and least by nylon. For silk and nylon, partial contact with the skin prolonged the return to control conditions, as compared with full skin contact.

A study was made to observe the association between the resistance to reinfection induced by irradiated metacercariae (MC) of Clonorchis sinensis and antigen specific Key words: irradiation -metacercariae -reinfection -interferon-γ -interlukin-2 Liver fluke infection caused by Clonorchis sinensis is still an important public health problem in many countries of the West Pacific area. It is estimated that about 30 million people are infected annually with C. sinensis or Opisthorchis viverrini by eating uncooked fresh water fish in Southeastern Asia (Rim et al. 1981, Akai et al. 1994). Studies about effects of irradiation on infective stage of C. sinensis have been reported (Lee et al. 1989, Song et al. 1992, Duan et al. 1993, and reports show that suitable dose of irradiation on isolated metacercariae (MC) or unisolated MC in fish can prevent infections. There are evidences from immunological studies that man and animals produce antibodies and cellular immunity after C. sinensis infections (Choi & Park 1987, Choi et al. 1990, Hagan et al. 1991, Akai et al. 1994, Quan et al. 2000, 2002. To the best of our knowledge no study was carried out on the association between the effects of gamma irradiation and immune responses in clonorchiasis. However, study on Schistosoma mansoni showed that high levels of protection have been achieved in mice against S. mansoni infection using gamma irradiated cercarial vaccines (Dean 1983, Coulson 1997. Also Th1-or Th2-type cytokines were reported to associate with protective immunity against various parasites (Stevenson & Tam 1993, Cetre et al. 1999 Koyama et al. 1999). In the present study, C. sinensis MC were first treated with different dose of gamma irradiation to select the suitable dose for the study of immune responses. Then resistance to reinfection induced by irradiated MC of C. sinensis was evaluated and an association between resistance and Th1-and Th2-type cytokines were observed. MATERIALS AND METHODSParasites and experimental animals -SpragueDawley (SD) rats (female, 8 wk old) were purchased (Samyook animal center, Osan-shi, Kyonggi-do, South Korea) and used for whole experimental process. Parasites C. sinensis MC collected from Pseudorasbova parva were used for infection of rats and rabbits. Male white rabbits (New Zealand white) about 1.5 to 2 kg were used to recover adult C. sinensis for collection of C. sinensis excretory-secretory antigen (ES Ag). All procedures involving animals and their care were in conformity with institutional guidelines that comply with national and international laws and policies.Irradiation -MC were dispensed into each micro tube (1.5 ml) containing 200 µl saline. The MC in the tube were given irradiation with single dose from 0 to 100 Gy (1 Gy = 100 rad) and irradiated at the rate 375 rad/min at 70 cm distance from the source, using 60 Co (Thrateron 780, AECL, Canada) gamma-ray.Antigen preparation -C. sinensis MC were collected from P. parva and digested with artificial gastric juice, and orally administered to the experimental rabbits. Th...

Local sweat rates (Msw) at the chest and thigh and the frequency of sweat expulsions (Fsw) were determined in human subjects with (athletes) or without (non-athletes) long-term physical training during moderate bicycle exercise (80 W for 30 min) at ambient thermoneutrality (23 degrees C) and 60% relative humidity. There was a tendency for Msw to be lower in athletes. The rise of Msw with increasing Fsw was significantly less steep and Fsw was also controlled at a significantly lower rate in athletes than in non-athletes. The start of exercise was followed by a temporary decrease in mean skin temperature (Ts) which was less distinct in athletes. The rise in Ts at the end of exercise was significant in athletes (0.80 +/- 0.26 degree C) but not in non-athletes (0.26 +/- 0.33 degree C). The results indicate that long-term physical training leads to improved circulatory heat transfer to the skin and to a more graded nervous control of sweat expulsion and, further, tends to reduce the rate of sweating.

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