Exposure limits of women in hot environment.

The tolerance of six women to work in hot environments was examined under four environmental conditions from 38 to 44 degrees C dry bulb temperature and 50 to 80 per cent relative humidity, i.e., 32 to 36.5 degrees C effective temperature [ET (normal scale)] in a climatic chamber. The subjects performed bicycle ergometric work at an intensity of 50 W and the exposure duration was determined by the cardiorespiratory, body temperature and sweating responses. At the limit of tolerance, the body core temperature (Tcr) reached over 38.5 degrees C and the heart rates attained a peak level (i.e., about 172 beats/min). The total oxygen demand decreased significantly with higher environmental load, particularly beyond 33.5 degrees C ET (N). While the tolerance time decrement was evident with the higher heat stress, on an average, an increase or decrease of every liter of total oxygen demand was equivalent to a 0.8 min change in the tolerance time. As such, the women volunteers were not susceptible to heat; only in extreme hot situations beyond 33.5 degrees C ET (N), they had unacceptable levels of physiological and psychophysical reactions. Based on the distribution of tolerance time of the women in different exposure conditions, the safe exposure times were estimated, which varied from 43 min [32.0 degrees C ET (N)] to 16 min [36.5 degrees C ET (N)].

Human heat tolerance in simulated environment.

The heat tolerance of 11 male volunteers were examined under seven climatic conditions in a climatic chamber. The conditions were 38 to 49 degrees C dry bulb temperature and 45 to 80 per cent relative humidity, i.e., 32.3 to 40 degrees C effective temperature-basic [ET(B)]. The ET(B) values were equated to other heat stress indices, e.g., WBGT (Wet-bulb Globe Temperature Index) and Oxford Index. The subjects did ergometric work at an intensity of 60 per cent VO2max. The exposure durations were decided by the cardiorespiratory, body temperature and sweating responses. Of the climatic conditions studied, at 35.4, 38, 39 and 40 degrees C ET(B), the body core temperature (Tcr) reached over 39 degrees C and heart rates attained 172 to 182 beats/min, which were taken as the tolerance limit. The total oxygen demand significantly varied with the increase in environmental warmth, i.e., increase or decrease of one litre of oxygen demand was equivalent to one minute change in tolerance time. The volunteers were not susceptible to heat; only in extreme hot situations beyond 35.4 degrees C ET(B), were unacceptable levels of physiological and psychophysical reactions seen. The study suggests the acceptable and tolerable limits for human exposure in heat: (i) acceptable at 38 to 38.2 degrees C Tcr for a tolerance time of 80 to 85 min; and (ii) the tolerable limit of short duration (40-45 min) at 39 degrees C Tcr that corresponded to 31.5 and 36.5 degrees C ET(B).

Influence of alcohol intake on high density lipoprotein cholesterol levels in middle-aged men.

To study the influence of alcohol (ethanol) intake on high density lipoprotein cholesterol (HDLC) levels, we studied 210 healthy middle-aged men (age 45 +/- 8 years). Other factors influencing HDLC (physical exercise, diet, smoking and body mass index) were also studied. Individuals were classified according to daily ethanol consumption. There were 39 teetotallers, 29 took drink, 30 took 1-1.9, 25 took 2-2.9, 26 took 3-3.9, 28 took 4-4.9 and 33 took 5 or more drinks per day (1 drink = 14 gm ethanol). The overall mean serum total cholesterol was 191.4 +/- 53 mg/dl and HDLC was 46.4 +/- 9 mg/dl. Total cholesterol in teetotallers was not different from those consuming different amounts of alcohol. HDLC in teetotallers (44.5 +/- 8 mg/dl) was significantly lower than in those taking 1-1.9 drinks (46.7 +/- 11 mg/dl, p < 0.05) and 2-2.9 drinks/day (51.4 +/- 9 mg/dl, p < 0.01) but was not different from those consuming > or = 3.0 drinks. There was a weak positive linear correlation between ethanol and HDLC (r = 0.016). HDLC levels were significantly lower in smokers (43.5 +/- 9 vs 47.2 +/- 11 mg/dl in non-smokers), in non-vegetarians (43.5 +/- 10 vs 46.2 +/- 9 mg/dl in vegetarians) and in those with sedentary habits (42.4 +/- 7 vs 46.1 +/- 10 mg/dl in physically active). Low level ethanol consumption (< 3 drinks or 42 gm per day) is associated with increased HDLC levels.

Acute diarrhoea caused by Vibrio mimicus in Calcutta.

Out of 539 acute diarrhoea cases studied, Vibrio mimicus was isolated as a sole pathogen in the faeces of 7 (1.3%) cases. The chief clinical presentations of the seven cases were watery diarrhoea and vomiting. Bloody diarrhoea was observed in 2 (28.5%), abdominal pain in 2 (28.57%) and fever in one (14.29) cases. All cases could be effectively treated with ORS except 3 (42.85%) cases who required IV Ringer's lactate. All V. mimicus strains isolated in the study were uniformly susceptible to tetracycline, chloramphenicol, norfloxacin and ciprofloxacin.

Clinical manifestation of Clostridium difficile enteritis in Calcutta.

233 cases with acute diarrhoea investigated, Clostridium difficile was isolated as a sole pathogen from 17 (7.3%) cases. The Major clinical features of these cases were watery diarrhoea (82.4%), bloody stool (17.6%), vomiting (64.8%), fever (17.6%) and abdominal pain (2.5%). Fourteen (82.4%) of 17 C difficile isolates were found to produce cytotoxin as detected by Verocell assay.

Sialic acid in human semen.

Sialic acid of seminal fluid of eighty two human subjects has been studied in relation to infertility. Normozoospermic group had highest sialic acid content (94 mgm/100 ml of the fluid) and was significantly different from other groups. The lowest sialic acid level was observed in necrozoospermic group (54 mgm/100 ml of the fluid). Azoospermic (62 mgm/100 ml) and vasectomised group (73 mgm/100 ml) had 33 and 22 percent less sialic acid level respectively than normozoospermic group. For the pooled observation sialic acid was found to be correlated (r = 0.282, significant at 5 percent level) with the total sperm count.