Search PubMed⌕ Search

Biomedical subjects

H H Cheng

Publications and source records attributed to H H Cheng.

106 records · Page 6Linked to original sources

The prevalence of antibody to delta virus in western Canada.

To assess the prevalence and pathological role of hepatitis D virus (HDV) infection in western Canada, we tested a total of 310 sera from the province of Alberta, Yukon and Northwest Territories for antibody to HD (anti-HDV) by commercial solid phase radioimmunoassay. Two hundred and forty-five sera were hepatitis B surface antigen (HBsAg) positive. These were classified on the basis of clinical and biochemical data as either acute hepatitis, chronic hepatitis or in the healthy carrier phase of infection Sixty-five HBsAg negative sera from patients with other forms of chronic liver diseases served as controls. Anti-HDV was detected in only four of the HBsAg positive sera (1.6%) and in none of the controls. The prevalence of anti-HDV was significantly higher in patients with chronic hepatitis, three of twenty-two (13.6%) than in patients with acute hepatitis (0%) (p less than 0.05) or healthy carriers (0%) (p less than 0.005). Two of the four anti-HDV positive sera were obtained from patients with a history of parenteral drug abuse. These results indicate that HDV infection is uncommon in western Canada but, when it does occur, is more likely to be associated with chronic inflammatory liver disease. Parenteral drug abuse appears to be the major risk factor for HDV infection in western Canada at this time.

Acute Disease↗

Free transplantation of venous network pattern skin flap: an experimental study in rabbits.

Free skin flaps using rabbit ear to replace rabbit scalp have been accomplished using only arteriovenous and venous-venous anastomosis, without arterio-arterial anastomosis. The technique produced excellent graft survival in 30 of 33 rabbits. Without the vascular anastomosis control grafts did poorly. The mechanism of flow reversed revascularization is discussed.

Animals↗

Coverage of wounds in the distal lower leg by advancement of an enlarged medial gastrocnemius skin flap.

Advancement of a medial gastrocnemius flap is a new technique in treating skin defects of the lower third of the lower leg, including that at the anteromedial aspect of the distal portion of the lower leg. Satisfactory results have been obtained in two clinical cases using this technique. In this modified technique, the size of the flap is enlarged, the origin of the medial head of the gastrocnemius is severed so that the island myocutaneous flap may be advanced 8 to 9 cm distally, and good blood supply to the flap is also maintained. In the authors' opinion, this method is a new approach that is simple, easy, safe, and reliable in treating skin defects of the lower leg.

Adult↗

Non-lethal Candida albicans cph1/cph1 efg1/efg1 transcription factor mutant establishing restricted zone of infection in a mouse model of systemic infection.

The cph1/cph1 efg1/efg1 Candida albicans mutant cells were non-lethal in a mouse model of systemic infection. We investigated in vivo proliferation and invasion of C. albicans cells in infected mice to elucidate the interaction between the host and the pathogen. Homogenates of kidneys from the mice infected with the wild-type and the mutant C. albicans cells yielded a mean of 2.1 x 10 7 CFU/g and 2.2 x 10 6 CFU/g, respectively. The kidneys from the mice infected with the wild-type cells showed extensive renal cortical necrosis associated with neutrophilic infiltration. There were also wild-type hyphal cells present in abundance. Hence, tubular necrosis leading to renal failure in the mice may be the cause of death. Although the cph1/cph1 efg1/efg1 mutant cells were not lethal, they were capable of establishing restricted zones of infection and colonization near the renal pelvis instead of simply being cleared by the immune system in mice.

Animals↗

Does a high peritoneal transport rate reflect a state of chronic inflammation?

OBJECTIVE: It has recently been reported that a high peritoneal transport rate was associated with increased mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. One possible explanation is that a high peritoneal transport rate might be caused by a state of chronic inflammation, which also per se might result in increased mortality. Therefore, in this study we investigated whether high peritoneal transport rate patients are in a state of chronic inflammation. METHODS: The study included 39 clinically stable peritoneal dialysis patients (free of peritonitis) who had been on PD for more than 3 months (16.8+/-11.8 months). Seven patients were treated with continuous cycling peritoneal dialysis (CCPD) and the others were on CAPD. A 4-hour standard peritoneal equilibration test (PET) using 2.27% glucose solution was performed in each patient. Dialysate samples at 4 hours and blood samples at 2 hours were measured for interleukin-1beta (IL-1beta), tumor necrosis factor(alpha)(TNFalpha), C-reactive protein (CRP), and hyaluronan as markers of inflammation. RESULTS: There was no significant correlation between dialysate/plasma (DIP) creatinine (0.82+/-0.15, range 0.51 - 1.15) and blood concentrations of IL-1beta (11.2 ng/L, range <5 - 65.9 ng/L),TNFalpha (12.1 ng/L, range <5 - 85.4 ng/L), CRP (<10 mg/L, range <10 - 76 mg/L), nor with the blood hyaluronan concentration (165 microg/L, range 55 - 955 microg/L). The dialysate concentrations of IL-1beta and TNFalpha were below the detectable level in most of the samples. Although dialysate hyaluronan concentration (334 microg/L, range 89 - 1100 microg/L) was correlated with D/P creatinine (r= 0.36, p< 0.05), there was no correlation between the total amount of hyaluronan in the effluent and D/P creatinine. However, a significant correlation was found between serum hyaluronan concentration and glomerular filtration rate (GFR) (r = -0.49, p< 0.005); GFR also tended to be correlated with serum TNFalpha (r = -0.31, p = 0.058) but not with serum IL-1beta and serum CRP. CONCLUSION: Our results suggest that a high peritoneal transport rate is not necessarily related to a state of chronic inflammation in CAPD patients. The high mortality rate observed in high transporters may relate to other issues, such as fluid balance or abnormal nutrition and metabolism, rather than to chronic inflammation.

Biological Transport↗

Correlations of serum lipids, uric acid, and albumin among mothers, offspring, and siblings in Taipei, Taiwan.

The purpose of this study was to investigate the correlations of serum lipids, uric acid, and albumin, among mothers (n = 111), offspring (n = 208), and siblings (n = 57) in Taipei, Taiwan. Analytical items included serum triglyceride, serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin. Statistical analysis was performed according to the SAS UNIVARIATE procedure; while regression coefficient, parent-offspring regressions, paired-comparison and heritability were estimated. These results show higher heritabilities of four types of serum lipids, uric acid and albumin between mothers and testers (bYX) or siblings (bZX) by parent-offspring regression analysis. Regression coefficients (bYX) of six characters were significantly different (p < 0.05-0.01). Regression coefficients (bZX) for total cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin were significantly different (p < 0.05-0.01), showing the result of genetic control, because their heritabilities were very high at 0.75-1.0, 0.77-1.0, 0.96-1.0, and 0.48-0.82, respectively. This study disclosed that the serum lipids of children in Taipei, Taiwan were significantly correlated with that of parents, which may be attributed to the result of genetic control.

Child↗

Kimura's disease in a teenage male: report of one case.

A 14-year-old boy gradually developed several subcutaneous masses over bilateral peri-auricular regions, neck, and both upper arms near the elbows over the past 2 years. The recent development of eyelid puffiness elicited his seeking medical attention. Hypereosinophilic syndrome was first considered due to the markedly elevated blood eosinophil count without other evidence of allergy or parasite infestation, but the absence of organ involvement made this diagnosis questionable. The histopathological investigation of the subcutaneous mass in the upper arm showed lymph node-like tissue with markedly reactive follicular hyperplasia and eosinophilic abscesses associated with granulomatous inflammation, thus leading to the final diagnosis of Kimura's disease. Oral prednisolone was prescribed successfully. This illness occurs mainly in young oriental males. We report this case to introduce it to pediatric clinicians as an important differential diagnostic entity in eosinophilia-associated diseases and reactive lymphadenopathy.

Adolescent↗

Fluid and solute transport using different sodium concentrations in peritoneal dialysis solutions.

BACKGROUND: Fluid and sodium balance is important for the success of long-term peritoneal dialysis. Convective transport is the major determinant for sodium removal during peritoneal dialysis using conventional dialysis solutions. However, recent studies showed that lower sodium concentration in dialysate could significantly increase sodium removal by increasing the diffusion gradient, thereby increasing diffusive transport. In the present study, we investigated the influence of the sodium concentration gradient on the diffusive transport coefficient, K(BD) for sodium. METHODS: A 4-hour dwell study was done in Sprague-Dawley rats using 25 mL 5% glucose (NS), 5% glucose + 0.3% NaCl (LS), 5% glucose + 0.6% NaCl (MS), or 5% glucose + 0.9% NaCl (HS), with frequent dialysate and blood sampling. Radiolabeled human albumin (RISA) was added to the solution as an intraperitoneal volume marker. The peritoneal fluid and sodium transport characteristics were evaluated. RESULTS: Significant ultrafiltration (both net ultrafiltration and transcapillary ultrafiltration) was observed in each group despite the osmolality of the 5% glucose solution being slightly lower than the plasma osmolality. There was no difference in peritoneal fluid absorption rate and direct lymphatic absorption among the four groups. With the sieving coefficient for sodium set to 0.55, a significantly higher K(BD) for sodium was found in the NS compared to the HS group. The K(BD) for sodium was 0.21+/-0.01, 0.20+/-0.01, 0.17+/-0.01, and 0.09+/-0.01 mL/min for the NS, LS, MS, and HS groups, respectively. The K(BD) values for glucose were significantly lower in the NS and LS groups compared to the MS and HS groups. CONCLUSIONS: Our results suggest that (1) sodium concentration may affect peritoneal sodium K(BD)--as the sodium concentration gradient increased, the K(BD) decreased; (2) 5% glucose solution could induce significant peritoneal ultrafiltration in normal rats despite its initial hypo-osmotic nature, this was due to the significantly lower glucose transport rate than sodium transport rate; and (3) a lower dialysate sodium concentration may decrease peritoneal glucose absorption.

Animals↗

Hyaluronan preserves peritoneal membrane transport properties.

BACKGROUND: We have shown that intraperitoneal (i.p.) addition of hyaluronan (HA) in a single dwell study in rat could increase peritoneal fluid removal by decreasing the peritoneal fluid absorption rate. In this study, we investigated the impact of repeated use of HA on peritoneal membrane transport characteristics. METHODS: Twelve male Sprague-Dawley rats received a once-daily i.p. injection of 25 mL 4.25% glucose dialysis solution without (HP group, n = 6) or with 0.025% HA (HA group, n = 6) for 1 week. Forty-eight hours after the last injection, a 4-hour dwell using 25 mL 4.25% glucose dialysis solution with i.p. volume marker and frequent dialysate and blood samplings was performed in each rat as well as in rats that did not receive any injection (control group, n = 8). RESULTS: Although the i.p. volumes were significantly lower in the HP and HA groups compared to the control group, i.p. volume in the HA group was significantly higher than in the HP group. Net ultrafiltration at 4 hours was 5.6 +/- 1.3 mL, 10.2 +/- 1.8 mL, and 13.2 +/- 0.6 mL for the HP, HA, and control group, respectively. The peritoneal fluid absorption rate decreased by 45% in the HA group compared to the HP group. There was no significant difference in peritoneal fluid absorption rate between the HA and the control group. No difference was found in the direct lymphatic absorption rate between the HP and HA groups [0.010 +/- 0.003 mL/minute in the HP group and 0.011 +/- 0.004 mL/min in the HA group] although they were both higher than that of the control group (0.004 +/- 0.001 mL/min). The solute transport rates were in general significantly higher in the HP group compared to the HA and control groups, and there was no significant difference between the latter two groups, except that protein transport rate was significantly lower in the HA group compared to the control group. CONCLUSIONS: The present study suggests that (1) repeated exposure to hypertonic glucose-based dialysis solution results in increased peritoneal solute transport rates, as well as increased peritoneal fluid absorption rates; and (2) these changes, reflecting a highly permeable peritoneal membrane, were ameliorated by repeated i.p. addition of hyaluronan. The similar changes in the direct lymphatic absorption rate in rats that received daily i.p. injection of dialysis solution suggest that direct peritoneal lymphatic absorption was not influenced by hyaluronan.

Absorption↗

Peritoneal fluid and solute transport with different polyglucose formulations.

OBJECTIVE: To study peritoneal fluid and solute transport characteristics using different polyglucose solutions with and without the addition of glucose. DESIGN: Thirty-one rats were divided into three groups. A 4-hour dwell study with frequent dialysate and blood samples was performed in each rat using 25 mL of 7.5% polyglucose solution (PG, n = 11), 7.5% polyglucose + 0.35% glucose solution (PG1, n = 12), or 3.75% polyglucose + 1.93% glucose solution (PG2, n = 8). Radiolabeled human albumin (RISA) was added to the solutions as an intraperitoneal volume (i.p.V) marker. In addition, polyglucose degradation was evaluated ex vivo over 24 hours. EXPERIMENTAL ANIMALS: Thirty-one male Sprague-Dawley rats (300 g) were used. MAIN OUTCOME MEASURES: Fluid and solute (glucose, urea, sodium, potassium, and total protein) transport characteristics as well as changes in dialysate osmolality were evaluated. RESULTS: The i.p.V was higher in the PG1 and PG2 groups than in the PG group during the first 2 hours of the dwell. The i.p.V, in fact, decreased during the first hour of the dwell in the PG group. However, the net ultrafiltration at 4 hours tended to be lower in the PG2 (3.2 +/- 1.5 mL) group compared to the PG (5.1 +/- 2.3 mL) and the PG1 groups (5.2 +/- 2.1 mL) (p = 0.07), and no significant difference was found between the PG and PG1 groups. Adding glucose to the PG solution increased the RISA elimination rate (KE, representing the fluid absorption rate from the peritoneal cavity): 25.5 +/- 8.2, 37.5 +/- 12.2, and 42.5 +/- 8.9 microL/min for the PG, PG1, and the PG2 group, respectively, p < 0.01. Dialysate osmolality (D[OS]) increased with the dwell time in the PG and PG1 groups but decreased in the PG2 group.The increase in D(OS) was partially due to the degradation of glucose polymer, which was supported by the marked increase in osmolality over 24 hours of incubation of PG solution with peritoneal fluid, ex vivo. The diffusive mass transport coefficient for the investigated solutes did not differ among the three groups (except for glucose, which was significantly lower in the PG group). The sieving coefficient for sodium was significantly higher in the PG group compared to the PG1 group (p < 0.05). CONCLUSION: Our results suggest that, although there was an initial decrease in the intraperitoneal dialysate volume, significant amounts of fluid can be removed by polyglucose solution during a single 4-hour dwell in rats, despite the low osmolality of the solution. The positive fluid removal induced by the PG solution is partially due to the lower fluid absorption rate associated with this solution and may, to some extent, also be due to the degradation of glucose polymer within the peritoneal cavity, resulting in increased dialysate osmolality. The addition of glucose to the polyglucose solution does not seem to improve ultrafiltration in a 4-hour dwell in the rat model. However, the peritoneal fluid absorption rate may be increased, and peritoneal transport of glucose and sodium may be altered, by adding glucose to the polyglucose solution.

Animals↗