Biomedical subjects

Y H Lai

Publications and source records attributed to Y H Lai.

At least 19 recordsLinked to original sources

PubMed1992

Comparisons of the effects of calcium carbonate and calcium acetate on zinc tolerance test in hemodialysis patients.

Because aluminum hydroxide, as a phosphate binder, lowered intestinal zinc absorption, we studied the effects of calcium carbonate (CaCO3) and calcium acetate (CaAc), two other phosphate binders, on intestinal Zn absorption in nine patients on hemodialysis and in 11 controls by measuring 1- and 2-hour serum Zn levels after oral administration of 50 mg of elemental Zn as Zn gluconate with or without concomitant administration of 2 g CaCO3 (800 mg elemental Ca) or 3 g CaAc (750 mg elemental Ca). Fasting serum Zn levels were not different between patients and controls (14.0 +/- 2.3 v 14.1 +/- 1.2 mumol/L [91.8 +/- 14.9 v 92.3 +/- 8.0 micrograms/dL]), but the area under the curve of serum Zn increment (AUC) 2 hours after an oral Zn challenge without or with either of two of phosphate binders used was significantly smaller in patients than in controls (P less than 0.05). The AUC after concomitant administration of Zn with CaCO3 did not differ from that of Zn alone in either patients or controls, but it was significantly less in Zn with CaAc than in Zn alone or in Zn with CaCO3 in both groups. The results demonstrate that intestinal Zn absorption after an oral Zn challenge decreased in patients on hemodialysis and concomitant administration of CaAc, but CaCO3 did not decrease intestinal Zn absorption in either group.

Acetates↗

PubMed1991

Plasma atrial natriuretic peptide and natriuretic response to water immersion in patients with nephrotic syndrome.

Eight nonnatriuretic (daily Na excretion less than 50 mEq), 4 natriuretic (daily Na excretion greater than 50 mEq), and 4 steroid-responsive nephrotic patients, and 12 normal controls were studied with a 4-hour water immersion with measurements of electrolytes, plasma atrial natriuretic peptide (ANP), plasma renin activity (PRA), and plasma aldosterone (PA) [corrected]. Four nonnatriuretic patients further received 25 g albumin infusion, with a subsequent 2-hour water immersion study. The results are as follows: (1) In the nonnatriuretic patients, the extremely low basal Na excretion rate, high PRA, and PA levels indicated a state of active Na retention. In spite of the water-immersion induced suppression of PRA and PA and a comparable magnitude of plasma ANP increment, the natriuretic response to water immersion was blunted in the nonnatriuretic patients. (2) In the natriuretic patients, water immersion resulted in a similar magnitude of natriuresis but a higher degree of plasma ANP increment in comparison to the normal controls. (3) Natriuretic and plasma ANP responses to water immersion were not different between the steroid-responsive patients and normal controls. (4) The increase in plasma ANP and the suppression of PRA and PA after 25 g albumin infusion did not result in natriuresis until the further suppression of PRA and PA and the further stimulation of plasma ANP by subsequent water immersion. The above results indicate that the natriuretic and plasma ANP responses to water immersion are related to the basal Na status in nephrotic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

Epidermal growth factor in renal hypertrophy in streptozotocin-diabetic rats.

Epidermal growth factor (EGF) concentrations in the plasma, kidneys and urine of 31 streptozotocin-diabetic rats and 21 insulin-treated diabetic rats were measured to study the role of EGF in initiating renal hypertrophy in the diabetic rats. Renal hypertrophy occurred from day 7 in the diabetic rats, but not in the insulin-treated rats. Renal EGF was not different between the diabetic and control rats, while that in the insulin-treated rats was significantly less than in the diabetic rats. There were no significant changes in plasma EGF in any of the rats. Urine EGF was 119 +/- 7.9 ng/day at day 7 in the control rats but it was significantly increased from day 2 in the diabetic rats (320 +/- 52.9 ng/day at day 2 and 298 +/- 18.4 ng/day at day 7), while in the insulin-treated rats it was significantly less than that in the diabetic rats (134 +/- 8.34 ng/day at day 2 and 220 +/- 15.2 ng/day at day 7). Since the kidney is the main source of urine EGF and EGF has been shown to induce renal growth both in vitro and in vivo, we conclude that EGF may have initiated renal hypertrophy in diabetic rats.

Animals↗

PubMed1991

Clinical efficacy of recombinant human erythropoietin in the treatment of anemia in hemodialysis patients: influence of dosing regimen, iron status, and serum aluminum.

To evaluate the clinical efficacy of recombinant human erythropoietin (EPO) and its influencing factors in the treatment of anemia in hemodialysis (HD) patients, 17 chronic stable HD patients (10 males, 7 females; mean age: 46.0 +/- 2.6 years) with severe anemia were enrolled in this study. The study period (ranging from 5 to 11 months) was divided into the initial 12 weeks of correction phase and the subsequent maintenance phase. EPO, 1500 U initially, was administered intravenously twice weekly (BIW group, n = 10) or thrice weekly (TIW group, n = 7) at the end of each HD. Dose was doubled every 4 weeks until up to a maximum dose of 6000 U if increment of hematocrit (Hct) was less than 3%. At the end of correction phase, anemia was markedly improved. Hct and hemoglobin (Hb) increased from 19.3 +/- 0.8 to 28.7 +/- 1.1% and from 6.5 +/- 0.3 to 9.6 +/- 0.4 g/dl, respectively. Fifteen patients (88%) reached to the target Hct of 30% at 13.7 +/- 1.2 weeks. At the end of study, Hct and Hb was maintained at 29.1 +/- 0.7% and 9.6 +/- 0.3 g/dl, respectively. Requirement of EPO dose to reach the target and maintain the stable Hct (greater than or equal to 28%) was 99 +/- 14 and 62 +/- 11 U/kg/week, respectively. Laboratory parameters showed that serum iron, transferrin saturation, sugar and triglyceride decreased significantly and uric acid and aluminum (Al) increased significantly. There was no significant change in predialysis blood pressure, body weight, cardiac ratio, and ECG. Quality of life was markedly improved with the better subjective feelings, physical activity and Karnorfsky index. Common adverse effects included exacerbated hypertension (23%), hyperphosphatemia (18%), hyperkalemia (18%), and flu-like syndrome (12%). All of them could be managed by medical and dialysis treatment. Investigation of influencing factors on response to EPO suggests that 1) TIW group had a better response than BIW group 2) Response was better in patients with more adequate iron status and less severe Al burden. 3) Time to target Hct correlated approximately with basal serum Al levels but did not correlate with basal serum parathyroid hormone levels. In conclusion, low dose of EPO therapy corrects anemia effectively with minimal adverse effects in HD patients. Dosing regimen, iron status, and serum Al will influence the response to EPO.

Adult↗

PubMed1991

Continuous ambulatory peritoneal dialysis in diabetic patients with end-stage renal disease: experience with intraperitoneal insulin therapy.

Continuous ambulatory peritoneal dialysis (CAPD) is a valuable alternative to hemodialysis in treating uremic diabetics, and insulin can be injected directly into dialysate and absorbed intraperitoneally (IP). We evaluated the effect of IP supply of insulin in 9 uremic diabetics undergoing CAPD therapy. The 9 patients included 5 males and 4 females, with a mean age of 57 +/- 12 years old. The study showed that serum biochemistry was stationary during the treatment period except for the variable elevations of serum triglyceride and cholesterol. Hypertension was easily controlled in most patients. The insulin requirements ranged from 50 to 180 (129 +/- 34) units/day, which was 4.2 +/- 1.6 times higher than the subcutaneous doses before dialysis. Insulin added to the dialysate showed a high percentage of adsorption (55% to 65%) onto the plastic bag. The blood glucose levels varied less after an IP supply of insulin. The overall incidence of peritonitis was 8 episodes in 135 patient months (one episode every 16.9 patient months), and the average duration of hospitalization was 14.9 +/- 11.2 days/year. The cumulative survival rates were 89% in the first year and 74% in the second year. Our experience indicates that CAPD is an ideal treatment modality for uremic diabetics, and IP supply of insulin results in a good control of diabetes.

Adult↗

PubMed1990

Renal changes in heterozygous Fabry's disease--a family study.

Two sisters, one with a long history of proteinuria and the other of hematuria, came for examination. Physical examination and routine laboratory workups did not show any significant abnormalities. The renal ultrastructural changes in case 1 showed marked enlargement and foamy vacuolation of all the glomerular capillary visceral epithelial cells, which was not found in other glomerular cells. The renal changes in case 2 showed similar lesions but with fewer cells involved and also with less severity, but the involved cells showed marked lamellation within the vacuoles. The serum alpha-galactosidase activity was 4.9 and 3.0 nmol/h/mL serum, respectively (normal values, 12.1 +/- 1.6 nmol/h/mL serum, mean +/- SD, n = 11), thus confirming the heterozygous variety of Fabry's disease. Our findings in these two cases reveal that patients with heterozygous Fabry's disease may present with renal symptoms only, which may be either proteinuria or hematuria.

Fabry Disease↗

PubMed1990

Plasma atrial natriuretic peptide in patients with chronic renal failure.

Plasma atrial natriuretic peptide (ANP) levels were measured in non-dialyzed and dialyzed chronic renal failure (CRF) patients and in normal subjects. Changes in plasma ANP in response to hemodialysis (HD) and to isolated ultrafiltration (UF) were also investigated in dialyzed CRF patients. Plasma ANP levels were significantly higher in 28 non-dialyzed CRF patients than in 27 normal subjects (mean +/- SEM, 174.0 +/- 25.9 vs 25.0 +/- 1.9 pg/ml, p less than 0.001). Plasma ANP levels did not correlate with blood urea nitrogen or serum creatinine, however patients with advanced renal failure (creatinine clearance less than 10 ml/min) with cardiomegaly (cardiothoracic ratio greater than 50%) or hypertension (BP greater than 140/90 mmHg) had significantly higher plasma ANP levels than those who were not. A 6-hour HD significantly decreased the plasma ANP level (423.4 +/- 71.3 to 220.6 +/- 40.0 pg/ml, p less than 0.001) and body weight in 21 dialyzed CRF patients, and the decrement in plasma ANP showed a positive correlation with the decrement in body weight (r = 0.425, p = 0.056). In 8 dialyzed CRF patients, we further performed a 1-hour isolated UF for removal of isoosmotic intravascular fluid without changes in the solute concentrations, followed by a subsequent 5-hour HD. The decrease in plasma ANP during the 1-hour UF period was 68% of the total ANP decrement for the whole 6-hour study. The average plasma ANP level was decreased with 94.6 +/- 42.5 pg/ml/kg/h in the UF period compared to 3.5 +/- 1.4 pg/ml/kg/h in the HD period (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[Neuroelectrophysiological study in patients on long-term hemodialysis].

Uremic neuropathy is a common complication in patients on hemodialysis. Although there are still controversies over the pathogenesis of uremic neuropathy, neuroelectrophysiological study offers an objective and quantitative method of detecting this neuropathy, whether it is a question of axonal degeneration vs demyelination, sensory vs motor type, or distal vs proximal involvement. We also used the segmental latency of the median nerve to differentiate polyneuropathy from the carpal tunnel syndrome. Furthermore, this study also may serve as an important parameter for planning changes in different hemodialysis programs. Via the Medelec Mystro machine, we carried out an electrophysiological study of 38 hemodialysis patients. This study included motor and sensory nerve-conduction velocity studies and an H-reflex study of the tibial nerve. The incidence of polyneuropathy in patients on hemodialysis was 73.68%. Compared with normal controls, the velocity and amplitude of all tested nerves decreased significantly (P less than 0.01). The highest abnormal rate was the tibial nerve (73.7%). We found the severity of neuropathy did not closely correlate with the duration of hemodialysis (P greater than 0.05). Prolonged distal latency of the median motor and sensory nerves was about 50.0% and 31.6% respectively but prolonged segmental latency of the median sensory nerve was around 20% only. H-reflex of the tibial nerve was also significantly prolonged (P less than 0.01). We drew the following conclusions. First, polyneuropathy and carpal tunnel syndrome are common complications in patients on hemodialysis. Secondly, adequate hemodialysis can prevent the progression of uremic neuropathy. Thirdly, neuroelectrophysiological study may be used as one of the parameters for determining adequate hemodialysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Comparisons of peritoneal function between diabetic and nondiabetic patients with end stage renal disease.

Peritoneal function is the major determinant of the efficiency of peritoneal dialysis. To understand whether diabetes affects the peritoneal function, we performed the peritoneal clearance study in 9 diabetic and 16 nondiabetic patients with end stage renal disease. The ultrafiltration volume tended to be lower in diabetics after infusion of 1.5% Dianeal, although there were no statistically significant differences between them. The same results were obtained after infusion of 4.25% Dianeal. The glucose uptake after infusion of both 1.5% and 4.25% Dianeal was not significantly different between the two groups. The dialysate/plasma(D/P) concentration ratio was also not significantly different between the two groups, however the D/P ratio for BUN and uric acid was slightly higher in the diabetic group. The peritoneal clearance of smaller molecules such as BUN, creatinine, uric acid and phosphate also tended to be higher in diabetics after infusion of 1.5% Dianeal for 4 hours. The peritoneal clearance became higher when more hyperosmotic dialysate were used in both diabetics and nondiabetics. The above results indicated that diabetic patients with end stage renal disease might have a normal peritoneal function compared to nondiabetics.

Aged↗

PubMed1988