Fibrinolytic activity in end-stage renal disease

Recently, we described that in the physiologic state, urokinase concentration is higher in the renal vein than in the renal artery which suggests that the kidney is the essential organ providing urokinase to the systemic circulation. In end-stage renal disease (ESRD) patients, urokinase provided by the kidney may be decreased, and this might be the cause of decreased systemic fibrinolytic activity seen in ESRD. To study this possibility, we measured fibrinolytic profiles including urokinase, tissue plasminogen activator (t-PA) and fibrinolytic activity in the euglobulin fraction of ESRD patients and compared the results with those of two control groups consisting of renal transplantation patients and age- and sex-matched healthy controls. The euglobulin fibrinolytic activity was 92.2 +/- 14.8 BAU in the ESRD group, 108.7 +/- 13.5 BAU in the kidney transplantation (KT) group and 101.5 +/- 8.0 BAU in the healthy control group. Although it was lower in the ESRD than in the KT (p < 0.005) and the healthy control group (p < 0.005), there was no difference between the KT and the healthy control group. t-PA antigen was 1.2 +/- 1.3 ng/ml in the ESRD group, 3.5 +/- 1.7 ng/ml in the KT group and 3.1 +/- 2.1 ng/ml in the healthy control group. It was lower in the ESRD compared to the KT (p < 0.001) and the healthy control group (p < 0.001) but there was no difference between the KT and the healthy control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma t-PA and PAl-1 antigen concentrations in non-insulin dependent diabetic patients: effects of treatment modality on fibrinolysis

Basal plasma tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAl-1) antigen levels were studied in 49 non-insulin dependent diabetic patients (23 men, 26 women: ages 51.3 +/- 14.9 years) and 16 age matched non-diabetic subjects (9 men, 7 women: ages 49.8 +/- 12.2 years) as a control group. Compared to a control group, the diabetic patients had a significantly higher mean t-PA antigen (5.15 +/- 3.02 vs 3.20 +/- 2.30 ng/ml) and PAl-1 antigen (35.89 +/- 18.59 vs 17.60 +/- 15.36 ng/ml) levels (p < 0.05). Plasma t-PA antigen level was not influenced by each treatment modality. There was a significant decrease of plasma PAl-1 antigen level after Metformin administration compared to that of before Metformin administration (39.74 +/- 19.39 vs 25.14 +/- 16.18 ng/ml) (p < 0.05), and the insulin-treated group showed a tendency for a decrease of plasma PAl-1 antigen levels after insulin administration but this did not reach statistical significance (29.93 +/- 15.37 vs 17.32 +/- 10.60 ng/ml). Sulfonylurea did not change both plasma t-PA and PAl-1 antigen levels. In conclusion, diabetic patients have high t-PA and PAl-1 antigen levels. Biguanide reduced plasma PAl-1 antigen levels, which might play some helpful role in the improvement of chronic complications in NIDDM.

Effect of periodic transfusion on erythropoietin concentration in end stage renal disease

BACKGROUND

It has been reported that a feedback circuit exists between erythropoietin (EPO) concentration and the degree of anemia even in end stage renal disease (ESRD), and growing experience with subcutaneous EPO administration confirms that only slight increases in EPO levels are required to correct renal anemia. Keeping in mind these findings, if a small portion of reserved EPO production could be reactivated in ESRD, it might be biologically significant and vice-versa. From this viewpoint, it is conceivable that periodic long term transfusion might suppress EPO production in ESRD.

METHODS

In order to see whether periodic transfusion influences the EPO concentration in ESRD, a cross-sectional retrospective study was undertaken by reviewing medical records of 28 non-transfusion patients and 22 transfusion patients with ESRD undergoing hemodialysis.

RESULTS

The EPO concentration of the ESRD group (29.1 +/- 8.0 mU/ml) but only about one twentieth of the control group (578.8 +/- 69.1 mU/ml). In ESRD group, It was 27.9 +/- 8.0 mU/ml in transfusion group and 30.6 +/- 7.9 mU/ml in non-transfusion group. EPO concentration at varying hematocrit (Hct) levels did not differ between the non-transfusion group and transfusion group. There was an inverse relationship seen in the non-transfusion group (p < 0.05) but no relationship was seen between the EPO concentrations and varying Hct levels in the transfusion group. The EPO concentration at equal levels of Hct did not differ between the non-transfusion group and transfusion group. The relationship between EPO concentration and the changes in Hct during the observation period did not differ between the non-transfusion group and transfusion group. Both the total amount of transfusion and the frequency of transfusions did not influence EPO concentration.

CONCLUSION

periodic long term transfusion does not seem to decrease the sensitivity of the EPO producing cell to the degree of anemia in ESRD.

The effect of dilution, pH and ionic strength of plasma on t-PA precipitation in euglobulin fraction

In order to evaluate the influence of dilution, pH and ionic strength on the precipitation of t-PA and PAI-1 during euglobulin precipitation, we measured t-PA Ag, PAI-1 Ag and fibrinolytic activity in the euglobulin fraction made of pooled plasma from liver cirrhosis patients, under various conditions by changing pH, ionic strength and degree of dilution. The precipitation of t-PA Ag in the euglobulin fraction was enhanced by decreasing the ionic strength and greatest at pH 6.0. The fibrinolytic activity in the euglobulin fraction showed consistent changes with t-PA Ag under varying pH and ionic strength. The precipitation of t-PA Ag was not influenced by the dilution factor but the larger the dilution factor, the greater the PAI-1 and the smaller the fibrinolytic activity in the euglobulin fraction. PAI Ag in euglobulin fraction showed consistent changes with t-PA Ag in the euglobulin fraction regardless of the changes in ionic strength and pH. The amount of precipitation of t-PA and PAI-1 was increased by the presence of dextran sulfate, under varying pH, ionic strength and dilution conditions. Our results show that the currently used conditions for standard euglobulin precipitation are the most favorable for t-PA precipitation into the euglobulin fraction. The fibrinolytic activity exerted in the euglobulin fraction seems to depend on the amount of t-PA-PAI-1 complex rather than minimized protease inhibitor in the euglobulin fraction.

Urokinase concentration in the renal artery and vein

To compare the fibrinolytic activity between the renal artery and vein and the systemic circulation, we measured tissue-type plasminogen activator (t-PA), urokinase and total fibrinolytic activity in the blood samples from both the left and right renal artery and vein and the anterior cubital vein of 7 kidney donors. Englobulin fibrinolytic activity was significantly higher in the renal vein [106.6 +/- 5.6 blood activator units (BAU)] than in the renal artery (90.6 +/- 4.1 BAU; p less than 0.001) and cubital vein (94.3 +/- 6.3 BAU, p less than 0.005), but there was no difference between renal artery and cubital vein. t-PA Ag was 2.9 +/- 1.1 ng/ml in the renal vein, 2.6 +/- 1.0 ng/ml in the renal artery and 2.6 +/- 1.1 ng/ml in the cubital vein. There was no difference between renal artery, renal vein and cubital vein. Urokinase was significantly higher in the renal vein (3.3 +/- 0.4 ng/ml) than in the renal artery (2.4 +/- 0.4 ng/ml; p less than 0.001) and cubital vein (2.6 +/- 0.4; p less than 0.005), but there was no difference between the renal artery and cubital vein. In all cases, there was no difference in the fibrin(ogen) degradation product concentration between the renal artery and vein and the cubital vein. These findings suggest that the kidney may be an essential organ for providing urokinase to the systemic circulation.

Euglobulin fibrinolytic activity in NIDDM patients

The euglobulin fibrinolytic activity was measured in 56 non-insulin-dependent diabetics and 118 age-matched healthy controls before and after venous occlusion for 5 min at 100 mmHg of the left antecubital vein. In the basal state, fibrinolytic activity was impaired in diabetics compared with controls (93.1 +/- 6.7 vs 101.6 +/- 0.9 BAU) (P less than 0.05) and plasma fibrinogen level was increased but this did not reach statistical significance (467.3 +/- 264.1 vs 359.2 +/- 200.2 mg/dl). In diabetics, stimulated fibrinolysis following venous occlusion was depressed compared with controls (110.6 +/- 3.9 vs 121.6 +/- 1.9 BAU) (P less than 0.05). No relation of fibrinolytic activity to age, duration of diabetes, obesity, serum triglyceride, HbA1c, or 24 h proteinuria was demonstrated. In the diabetic retinopathy group, the fibrinolytic activity was lower than in the non-retinopathy group. Diabetics with long-standing diabetes (10 years or more) who remained free from retinopathy had significantly increased fibrinolytic activity than the diabetics with short-standing diabetes (less than 10 years) who have developed retinopathy (P less than 0.05). These findings imply a poor fibrinolytic activity, not in all diabetics, but only in those with retinopathy, and this may play a role in the development of diabetic retinopathy.

[Clinical effects and immune regulation of musk-moxa-string therapy in 39 patients with scrofula]

Immunological function and lymphocytic subsets of peripheral blood mononuclear cell (PBWC) from 39 patients with scrofula were investigated before and after treatment with musk-moxa-string therapy. The results showed that the percentage of CD3+, CD4+ cells and the ratio of CD4+/CD8+ cells were markedly decreased in the patients than normal control (P less than 0.001). On the contrary, the numbers of B lymphocytes and DR+ cells were increased. But the response of PBWC to phytohemagglutin in (PHA) stimulation markedly decreased in the patients than the normal control. After treatment with musk-moxa-string therapy, the percentage of CD3+, CD4+ cells and the ratio of CD4/CD8 were increased (P less than 0.001) and blastogenic response to mitogen stimulation with PHA recovered to normal. Meanwhile, the symptoms was improved and swell lymph node disappeared or was reduced markedly in size and the ulcer was healed completely. These findings suggest that the effect of musk-moxa-string therapy is caused by the enhancement of immunological capacity of the patients.

The urine urokinase concentration in end stage renal disease with acquired renal cyst

To see whether there was any difference in the urine urokinase concentration between acquired cystic kidney disease (ACKD) group and control (non cyst) group in end stage renal disease patients (ESRD), we evaluated fifty ESRD patients who had been maintained on chronic hemodialysis for various period. The urine urokinase concentration was higher in the ACKD group (17.5 +/- 14.7 unit/ml, range 13.5-47.0 unit/ml, n = 9) than the control group (4.1 +/- 3.4 unit/ml, range 0.5-12.0 unit/ml, n = 36) (p less than 0.001), and polycyst group (2.6 +/- 1.8 unit/ml, range 1.0-5.1 unit/ml, n = 5) (p less than 0.01). But there was no difference between the control group and polycyst group. In the control group and the ACKD group, there was a direct relation between the dialysis duration and the urokinase concentration and the longer the dialysis duration, the higher the urine urokinase concentration (r squared = 0.424, p = 0.0001). The hemodialysis duration was longer in the ACKD group (42 +/- 17.0 months) than the control group (20.0 +/- 12.5 months) (p less than 0.005). These findings suggest that urokinase may be responsible for cystogenic degeneration in ESRD.

Effect of 1,25-dihydroxyvitamin D3 on mesangial cell proliferation

We have studied the effect of 1,25-dihydroxyvitamin D3 (1,25, (OH)2D3) on mesangial cell growth. Previous studies have shown that the monocyte-macrophage is the principal effector cell in immune-mediated nephritis; this cell infiltrates the glomerular mesangium, and its products may have important effects on the physiology of the mesangial cell. One of the substances produced by the activated macrophage is 1,25,(OH)2D3. We have investigated the effect of 1,25,(OH)2D3 on mesangial cell growth and found that this vitamin D metabolite suppresses the proliferation of mouse mesangial cells as assessed by mesangial cell tritiated thymidine uptake and by cell counts; this substance also antagonizes the mitogenic effect of epidermal growth factor on mesangial cell growth. By comparison, the vitamin D metabolite 25 hydroxyvitamin D3 has no significant suppressive effect on the proliferation of mesangial cells. It has also been possible to demonstrate that 1,25,(OH)2D3 could suppress the growth of mesangial cells that had been committed to proliferate by the prior addition of epidermal growth factor. The results of these studies are relevant to our understanding of the pathogenesis of the cellular abnormalities that occur in immune-mediated nephritis, and especially in subjects who have concurrent hypertension, because a segment of subjects with hypertension have demonstrable abnormalities in the levels of circulating 1,25,(OH)2D3.

Immunoregulatory effects of phospholipase A2 (PLA2) on the proliferation of human lymphocytes

Extracellular phospholipase A2 (PLA2) is a proinflammatory enzyme found especially in the inflammatory exudate to modulate blood flow to areas of antigen stimulation. In this study we found that PLA2 exerted a biphasic effect on the proliferation of phytohemagglutinin (PHA)-stimulated human mononuclear cells (PHA MNC). At low concentrations range from 0.001 to 1 U/ml, PLA2 enhanced the proliferation of PHA MNC (maximal increase was 37.0 +/- 5.67%). Conversely, at concentrations over 10 U/ml, PLA2 markedly suppressed the PHA-induced MNC proliferation (maximal decrease was 88.86 +/- 2.89%). PLA2 was non-toxic to lymphocytes after three days culture, unless the concentration was higher than 100 U/ml. The membrane polarization of PHA-stimulated lymphocytes was also increased by PLA2 at a low concentration. In addition, PLA2 displayed a similar effect on the proliferation of streptokinase-streptodornase (SK/SD) or allogeneic cell stimulated lymphocytes. The change of lymphocyte proliferation by PLA2, was parallel to the change of percentage of helper T cells. Furthermore--a CD4-rich population was proved more susceptible to PLA2 effect than a CD8-rich population. Para-bromophenacyl bromide (pBPB), an irreversible inhibitor of PLA2, abrogated the biphasic effect of PLA2 on PHA MNC proliferation. These results suggest that PLA2 plays a regulatory role on immune reactions by modulating the percentage of helper T cells.

Circulating HBsAg/IgG complexes in idiopathic chronic glomerulonephritis

We measured HBsAg/IgG complexes (CX) quantitatively by ELISA from HBsAg positive serum of 35 liver disease patients, 15 patients with glomerular diseases (8 membranous glomerulonephritis (MGN) 7 membranoproliferative glomerulonephritis (MPGN), and 50 healthy carriers of HBsAg. HbsAg/IgG CX was detected in 26 out of 35 liver disease patients (74.3%), 5 out of 50 healthy carriers (10%), and one of both 8 MGN patients (12.5%) and 7 MPGN patients (14.3%). HBsAg/IgG CX was big in size and wide spread in the liver disease groups but negligible in the healthy carrier group (41 +/- 2.6 ng/ml, n = 5) and MGN (50 ng/ml, n = 1) and MPGN (42 ng/ml, n = 1) group. In the liver disease group, no one suffered from glomerulopathy even with a wide spectrum of HBsAg/IgG CX. These results suggest that HBsAg/IgG CX in plasma is non causative of MGN and MPGN.

Immunomodulation of musk-moxa-string therapy in patients with scrofula

The effects of musk-moxa-string therapy on the immune system in man were investigated in 39 patients with scrofula. Before treatment, the numbers of peripheral blood (PB) CD3+ and DC4+ cells and the ratio CD4+/CD8+ were found to be lower in patients with scrofula than in normal subjects, while those of B cells and DR+ cells were higher. Response of peripheral blood mononuclear cells (PBMC) to phytohemagglutinin (PHA) diminished in patients with scrofula. At month 2-6 of musk-moxa-string therapy the number of PB CD8+ cells showed slight diminution along with significant increases in CD3+ and CD4+ cells and CD4+/CD8+ ratio in total lymphocytes (P less than 0.001). In vitro a marked increased blastogenic response to mitogen stimulation with PHA was observed in PBMC of patients with scrofula after treatment (P less than 0.001). In contrast, B lymphocytes, monocytes, DR+ cells and blastogenic response to concanavalin A and pokeweed mitogen were not influenced by musk-moxa-string therapy.

A simple quantitative assay of vascular plasminogen activator--not only stimulated fibrinolytic activity but also basal fibrinolytic activity are correlated with venous fibrinolytic activity

A simple method for the quantitative assay of vascular plasminogen activator is described. From 24 chronic renal failure patients who were undergoing surgery for A/V fistular or shunt construction, small pieces of artery (mean 7.8 mg, range 3.0-18.5 mg) and vein (mean 4.5 mg, range 3.0-8.8 mg) were used. The fibrinolytic activity was assayed on a well-controlled fibrin plate by only distilled water immersion and incubation at 37 degrees C. Basal fibrinolytic activity was correlated with venous fibrinolytic activity (r = 0.773, p less than 0.0001) and with arterial fibrinolytic activity (r = 0.55, 0.005 less than p less than 0.01). The increment of fibrinolytic activity by venous occlusion was correlated to venous fibrinolytic activity (r = 0.849, p less than 0.0001) but not to arterial fibrinolytic activity (r = 0.34, 0.1 less than p less than 0.25).

Urinary plasminogen activator activity in progressive renal failure

The purpose of this study was to discover how functional nephrons produce the plasminogen activator as renal function progresses to renal failure. Urine Plasminogen activator (U-PA) activity was measured by the fibrin plate method in 73 patients with various degrees of renal function deterioration from various underlying diseases and in one healthy individual in order to evaluate the plasminogen activator activity of remnant nephrons. The plasminogen activator activity of the 12 consecutive urine samples from the healthy individual showed that is varied according to the time of day, but there was no circadian rhythm. The urine plasminogen activator activity correlated with the osmolality (r = 0.51, P less than 0.001) and creatinine (r = 0.56, P less than 0.001) of the urine, suggesting that it is concentrated at distal nephrons. The fractional sodium excretion rate (FeNa) increased abruptly when GFR decreased below 25 L/day. This pattern was very similar with the relation between total U-PA activity/GFR and GFR. The correlation between total U-PA activity and FeNa was not significant, but there was a significant direct correlation between total U-PA activity/GFR and FeNa (r = 0.775, P less than 0.0001). There was no relationship between the 24-hour urine protein and total U-PA activity or total U-PA activity/GFR.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of serum urokinase on urine fibrinolytic activity

The purpose of this study was to see if the serum level of urokinase might influence the urine fibrinolytic activity. Serum fibrinolytic activity precipitated in dextran sulfate euglobulin fraction was measured on the plasminogen-rich plate before, during, and after the urokinase infusion. The fibrinolytic activity of euglobulin increased during urokinase infusion by dose-dependent pattern (n = 4, mean: 230%, range: 173-333% of basal level) and decreased below the basal level after cessation of urokinase (n = 4, mean: 18%, range: 0-27% of basal level). There was inverse correlation between the urine fibrinolytic activity and serum fibrinolytic activity in all cases (r = -0.75, 0.01 less than p less than 0.02 in case 2; r = -0.88, 0.0001 less than p less than 0.005 in case 3; r = -0.74, 0.05 less than p less than 0.10 in case 1a and r = 0.59, 0.05 less than p less than 0.10 in case 1b). This finding suggests that the urine fibrinolytic activity production was under control of the serum urokinase level with feedback mechanism.

Fibrinolytic response to standardized venous occlusion in different age groups

The purpose of this study was to find out the range and distribution of fibrinolytic response to standardized venous occlusion in healthy volunteers and to determine whether there were any differences according to age and sex. In 118 healthy volunteers (55 males, 63 females) of various age groups, the total fibrinolytic activity in euglobulin fractions was measured by a well controlled fibrin plate method before and after venous occlusion of 5 minutes at 100 mmHg. The difference between our method and previous methods is that we occluded for a relatively shorter duration than that of previous studies (15-20 minutes) at constant pressure (100 mmHg), instead of midway between systolic and diastolic pressure. This method was reliable and reproducible as a tool to qualify and assess the fibrinolytic activity capacity of individuals. The results showed that there was no difference in basal fibrinolytic activity and the response to stimuli in various age groups (p greater than 0.25) and in male and female groups (0.1 less than p less than 0.375).

Determination of methylated amino acids in human serum by high-performance liquid chromatography

Employing high-performance liquid chromatography with isocratic elution using a two-column system (mu Bondapak C18 and mu Bondapak CN) and phenyl isothiocyanate as a fluorogenic reagent, NG-monomethylarginine (MMA). NG-dimethylarginines, and epsilon-N-trimethyllysine (TML) can be quatitatively separated from human serum samples. The recoveries of these amino acids were over 90%. It was observed that the serum concentrations of MMA, DMA and TML were significantly elevated in sera obtained from patients suffering from diabetes mellitus, hepatitis or hyperthyroidism, particularly the last condition.

Changes in thermal insulation during underwater exercise in Korean female wet-suit divers

The present work was undertaken to examine the effect of wet suits on the pattern of heat exchange during immersion in cold water. Four Korean women divers wearing wet suits were immersed to the neck in water of critical temperature (Tcw) while resting for 3 h or exercising (2-3 met on a bicycle ergometer) for 2 h. During immersion both rectal (Tre) and skin temperatures and O2 consumption (VO2) were measured, from which heat production (M = 4.83 VO2), skin heat loss (Hsk = 0.92 M +/- heat store change based on delta Tre), and thermal insulation were calculated. The average Tcw of the subjects with wet suits was 16.5 +/- 1.2 degrees C (SE), which was 12.3 degrees C lower than that of the same subjects with swim suits (28.8 +/- 0.4 degrees C). During the 3rd h of immersion, Tre and mean skin temperatures (Tsk) averaged 37.3 +/- 0.1 and 28.0 +/- 0.5 degrees C, and skin heat loss per unit surface area 42.3 +/- 2.66 kcal X m-2 X h. The calculated body insulation [Ibody = Tre - Tsk/Hsk] and the total shell insulation [Itotal = (Tre - TW)/Hsk] were 0.23 +/- 0.02 and 0.5 +/- 0.04 degrees C X kcal-1 X m2 X h, respectively. During immersion exercise, both Itotal and Ibody declined exponentially as the exercise intensity increased. Surprisingly, the insulation due to wet suit (Isuit = Itotal - Ibody) also decreased with exercise intensity, from 0.28 degrees C X kcal-1 X m2 X h at rest to 0.12 degrees C X kcal-1 X m2 X h at exercise levels of 2-3 met.(ABSTRACT TRUNCATED AT 250 WORDS)

A new HPLC analytical method for o-hydroxyhippuric acid in uremic serum

o-Hydroxyhippuric acid (HHA) is formed in liver during the process of detoxication of salicylic acid which arises from either salicylic-containing dietary vegetables or hydrolysis of aspirin. Recently, HHA has also been shown as one of the so-called 'uremic toxins'. By derivatization of HHA with o-phthaldialdehyde (OPA), the resulting fluorescent product can easily be measured with the limit of measurement somewhere below 3 pmol on high performance liquid chromatography. Using the method described, an approximately 85% recovery of added HHA in human sera was obtained. This analytical system is now being employed to determine the concentration of HHA in human sera of uremic patients. Determination of HHA content in human uremic patients is very important, since uremia is associated with defective binding of many acidic drugs to serum protein(s) and HHA replaces these drugs by tightly binding to these proteins. This could potentially affect the therapeutic effectiveness of various pharmacologic agents.

Studies on naturally occurring proteinous inhibitor for transmethylation reactions

An inhibitor for S-adenosyl-L-methionine (AdoMet)-dependent methyltransferases has been purified from rat liver particulate fraction to apparent homogeneity, as judged by high-performance liquid chromatography, two-dimensional paper electrophoresis and isoelectric focusing chromatography. This inhibitor molecule, which is composed of 27 amino acid residues with an additional fluorescent chromophore, is rich in glycine, contains no basic amino acid, and has an isoelectric point (pI) of 3.70. A single absorption peak was observed at 248 nm in acidic as well as in neutral media, while two peaks were detected in alkaline medium at 206 nm and 248 nm. The former peak was found to be quite labile. The fluorescent spectra with excitation peak at 285 nm and emission peak at 358 nm are greatly influenced by the pH, being the highest in alkaline medium. The purified inhibitor inhibits all the AdoMet-dependent methyltransferases examined.

Patterns of wet suit diving in Korean women breath-hold divers

Work shifts, diving pattern, diving lung volumes, and counterweights were studied in professional Korean women breath-hold divers wearing wet suits. One of the major differences, compared with their diving pattern only a few years ago when wearing cotton suits, is the prolongation of the diving shifts from 70 to 180 min in the summer and 10 to 120 min in the winter. In sustained diving the average dive and surface times in a 5-m dive are 32 and 46 s, and in a 10-m dives, 43 and 85 s, respectively. During a 3-h shift the total bottom time for harvesting is 37 min in 5-m dives and 17 min in 10-m dives. Rates of descent and ascent are 0.55 and 0.84 m/s. The wet suit divers adjust their counterweights to obtain a 12% positive buoyancy at the surface of sea water in contrast to the 8% positive buoyancy of cotton suit divers. The average lung volumes before and after a dive are 79% and 64% of their vital capacities, values similar to those of previous cotton suit divers.

Time course of deacclimatization to cold water immersion in Korean women divers

Seasonal basal metabolic rates (BMR), critical water temperature (Tcw), maximal body insulations (Imax), and finger blood flow during hand immersion in 6 degrees C water (Q finger) were measured periodically during the course of a 3-yr longitudinal study (1980-1982) of modern Korean diving women (ama), who have been wearing wet suits since 1977 to avoid cold stress during work. Methods and protocols were identical to previous studies of cotton-suited ama from 1961-1974. The BMR of modern ama did not undergo seasonal fluctuation (1980-1981) and was within the DuBois standard and comparable to nondivers year around Tcw of ama was still reduced by 2-3 degrees C in 1980 but increased progressively to equal that of nondivers in 1982, when compared at comparable subcutaneous fat thickness (SFT). Since modern ama and nondivers have 2.4 times thicker SFT (i.e., 4-13 mm) than in 1962 the absolute Tcw is significantly reduced. Q finger of ama was also significantly lower than controls in 1980 but in 1981-1982 was identical to controls. Imax of modern ama was identical to controls of comparable SFT in 1980-1982. The time course of cold deacclimatization thus was BMR, 3 yr; Imax, 3 yr; Q finger, 4 yr; and Tcw, 5 yr. This longitudinal study provides further evidence that acclimatization to cold did at one time exist in these diving women.

Energetics of wet-suit diving in Korean women breath-hold divers

Contemporary Korean women divers wear wet suits during diving work to avoid the cold water stress. The present study was undertaken to evaluate the effect of wearing wet suits on the daily thermal balance of divers and on the duration of diving work. Rectal (TR) and skin temperatures and O2 consumption (VO2) were measured in four divers before and during diving work in summer (22.5 degrees C water) and winter (10 degrees C water). Subjects wore either wet suits (protected) or cotton suits (unprotected) for comparison. TR decreased 0.4 degrees C in summer and 0.6 degrees C in winter after 2 h of diving work in protected divers, while it decreased to 35 degrees C in 60 min in summer and in 30 min in winter in unprotected divers. Mean skin temperature of protected divers decreased to 31 degrees C in summer and 28 degrees C in winter, while that of unprotected divers decreased to 24 degrees C in summer and 13 degrees C in winter. VO2 toward the end of the diving work period increased by 80 (summer) and 140% (winter) in protected divers and by 160 (summer) and 250% (winter) in unprotected divers. From these values total thermal cost of diving work was estimated to be 260 and 370 kcal . day-1 in summer and winter, respectively.