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Biomedical subjects

Z Q Huang

Publications and source records attributed to Z Q Huang.

At least 19 recordsLinked to original sources
PubMed1992

Parallel stranded DNA under the scanning tunnelling microscope.

Using scanning tunnelling microscopy, we have directly observed parallel stranded DNA helixes of 43 nucleotides in length. The double helix is right-handed and has an average spacing, 17.43 A (+/- 1 S.D.: 2.30 A), and an average apparent depth, 4.79 A (+/- 1 S.D.: 1.04 A) for each groove. The average pitch of the helical turn is 34 A (+/- 1 S.D.: 3.35 A) and consists of no more than ten base pairs. The diameter of the helix is approx. 17-20 A. Our results provide direct evidence for the existence of a parallel structure of DNA in vitro and some details of its fine structure.

Base Sequence↗
PubMed1992

Treatment of hypercholesterolemia: comparison of younger versus older patients using wax-matrix sustained-release niacin.

OBJECTIVE: Compare lipid response, side effect profile and toxicity of younger (less than 50 years) versus older (50 to 70 years) hypercholesterolemic subjects taking wax-matrix sustained-release niacin (Endur-acin). STUDY DESIGN: An 8-week randomized double-blind placebo controlled trial. SETTING: General community. PARTICIPANTS: Volunteers from community cholesterol screening programs and chart review of patients at family practice clinics. Male and female subjects, age 20 to 70, with baseline low density lipoprotein cholesterol level within the 75th to 95th percentile, excluded if on medications that affect lipids or if a history of diabetes, gout, peptic disease, or liver disease is present. INTERVENTION: Nicotinic acid dosage schedules were 1,000 mg/day, 1,250 mg/day, 1,500 mg/day, or 2,000 mg/day for 8 weeks. MAIN OUTCOME MEASURES: Change in blood lipids and blood chemistries, side effects, and pill compliance. RESULTS: 158 subjects (79%) completed the study. Higher dose groups (1,500 mg and 2,000 mg) demonstrated improvements in total cholesterol, LDL-cholesterol, HDL cholesterol, and total-to-HDL-cholesterol ratio (P less than 0.05) compared to baseline and controls. Higher-dose older subjects demonstrated significantly greater improvements than younger subjects on comparable doses for total cholesterol, HDL cholesterol, total-to-HDL-cholesterol ratio, and triglycerides, P less than 0.02). Adherence to medication schedules was better and incidence of side effects and toxicity no greater in older subjects compared to younger. CONCLUSION: Wax-matrix niacin (Endur-acin) was shown to be effective and well tolerated for the pharmacological treatment of hypercholesterolemia. Older persons, ages 50 to 70, appear to experience greater benefits with no greater side effects when compared to younger subjects on similar doses.

Adult↗
PubMed1992

[Research of the relation between the type of asthenia of the spleen and kidney and platelet associated antibodies and T-lymphocyte subsets in idiopathic thrombocytopenic purpura].

Idiopathic thrombocytopenic purpura (ITP) is a kind of disease associated with immunity. At present a great quantity of study on ITP has been made on humoral and cellular immunity. But there are few reports about the relationship between the types based on the differential diagnosis of TCM and immune rationale of ITP. In order to deeply explore the relationship between the types based on differential diagnosis of TCM and immune rationale of ITP., the authors measured PAIg and T lymphocyte subsets of 34 ITP patients of asthenia of both Spleen and Kidney. The value of PAIgG increased in both types of Spleen failing to control blood (SFCB) and deficiency of Spleen-yin and Kidney -yin (DSYKY), and the value of PAIgG of the type of DSYKY was significantly higher than that of SFCB (P less than 0.01). OKT3, OKT4/OKT8 of the type of SFCB remarkably decreased (P less than 0.05), OKT4, OKT4/OKT8 of DSYKY also remarkably decreased (P less than 0.001), while OKT8 significantly increased (P less than 0.001). The above results suggested that the type of DSYKY has more serious immune dysfunction than the type of SFCB, and the types of SFCB and DSYKY has close relationship with PAIg T lymphocyte subsets.

Adolescent↗
PubMed1992

Surgical treatment of hilar bile duct carcinoma. Clinical and pathological studies.

Resection of the extrahepatic bile tract for hilar bile duct carcinoma was performed at the PLA General Hospital, with a resectability rate of 62% (31/50) and no operative mortality. Hepatic lobectomy was performed at the same time in 16 cases (51.6%). Reoperative resections were successfully done in 5 cases; 4 cases are still living 1-4 years after the second operation. The cause of late death was mainly biliary infection due to local recurrence and bile duct obstruction. The median survival period was 15 months. 32 cases were studied pathologically, of which 27 were resected surgical specimens and 5 autopsies. The tumors were histologically classified into 4 types: papillary adenocarcinoma (6 cases); well differentiated adenocarcinoma (21); poorly differentiated adenocarcinoma (3); and simple carcinoma (2). The importance of early diagnosis of hilar bile duct carcinoma at its subclinical stage before appearance of clinical jaundice is stressed.

Adenocarcinoma↗
PubMed1992

[Risk factors of acute pancreatitis].

A total of 689 operative cases of acute necrotic pancreatitis (ANP) were collected from 42 hospitals all over the country by the ANP Cooperative Study Group in the years of 1987 to 1989. General data, laboratory findings, pathology of the pancreas and the type of surgical treatment were analysed according to the outcome of the patient. The results showed that 37% of the cases were related to cholelithiasis, the highest incidence was in age above 60, and female patients were predominant and with higher mortality. Laboratory findings at admission, WBC greater than 20,000/mm3, Hb greater than 15 g%, blood sugar greater than 200 mg%, serum bilirubin greater than 5 mg%, BUN greater than 20 mg%, and serum calcium less than 7 mg% were related to the markedly elevated mortality rate. Operative findings noted in patients with bloody or cloudy peritoneal fluid, necrotic changes up to 75% of the pancreas, more than 2 areas of extrapancreatic involvements and resection of a large portion of the pancreas was found to be necessary were all related to a higher mortality. And emergency operations performed within 24 hours after the onset of the disease was also related with a highest mortality rate.

Acute Disease↗
PubMed1991

Niacin revisited. A randomized, controlled trial of wax-matrix sustained-release niacin in hypercholesterolemia.

Two hundred one male and female subjects, aged 20 to 70 years, with elevated low-density lipoprotein cholesterol values (in the 75th to 95th percentiles), participated in a randomized, controlled, double-blind study using a new form of niacin (Enduracin), which employs a wax-matrix vehicle for sustained release. Four niacin treatment groups (daily doses of 2000, 1500, 1250, and 1000 mg) were compared with placebo- and diet-treated controls to determine side-effect profile and optimal range of efficacy. The groups given 2000 and 1500 mg demonstrated significant reductions in values of low-density lipoprotein cholesterol (-26% and -19.3%, respectively), total cholesterol (-18.4% and -13.3%), and total cholesterol-high-density lipoprotein cholesterol ratio (-20.4% and -19.4%) when compared with diet- and placebo-treated controls. Smaller improvements were seen in high-density lipoprotein cholesterol and triglyceride levels. Blood chemistry monitoring indicated that reduction in low-density lipoprotein cholesterol level strongly correlated with an increase in baseline levels of some enzymes for niacin-treated subjects. The improved side-effect profile of the wax-matrix form of niacin was particularly notable. The dropout rate due to side effects was only 3.4% and was coupled with good medication compliance.

Adult↗
PubMed1991

Randomized, controlled, crossover trial of oat bran in hypercholesterolemic subjects.

BACKGROUND: Despite animal and metabolic ward studies that support the benefit of oat bran as a useful dietary supplement for the lowering of cholesterol, there have been few controlled studies on free-living subjects that have convincingly demonstrated this benefit. METHODS: This is a report of a randomized, controlled, blinded clinical trial with a crossover design using oat bran (28 g [1 oz] twice daily) vs wheat cereal as a supplement to a fat-modified diet for the reduction of total cholesterol and low-density lipoprotein (LDL) cholesterol. The study included male and female subjects aged 20 to 70 years, with baseline LDL cholesterol in the 50th to 95th percentile. All subjects were instructed in the American Heart Association Step I (AHA-I) diet, and eating behavior was monitored using 4-day food records during each study period. RESULTS: Eighty-two percent (n = 145) of the total number of subjects who were randomized to treatment groups completed the study. Blood lipid studies demonstrated significantly greater reductions in total cholesterol (average -2.2%) and LDL cholesterol (average -3.9%) in the oat-bran groups than in the wheat-cereal groups (average total cholesterol +3.3%, average LDL cholesterol +4.0%) or in the diet alone group (total cholesterol +6.0%; LDL cholesterol +6.4%). All groups did comparably well at adhering to the AHA-I diet; however, dietary factors alone, when analyzed by the Keys equations, could not explain the group differences in lipid change. CONCLUSIONS: The addition of oat bran (28 g [1 oz] twice daily) to the AHA-I diet provided significant added benefit in lowering total cholesterol and LDL cholesterol in most hypercholesterolemic subjects. Analysis for factors that predict LDL cholesterol response to oat bran revealed a significant age-by-sex interaction (P less than .001). Women under the age of 50 years, as a group, showed essentially no increased benefit from the addition of oat bran to their diet. Cholesterol levels in older women appear to be significantly more responsive to a modified diet containing oat bran than those of younger women.

Adult↗
PubMed1991

[In vitro effect of shen-xue-ling on megakaryocytopoiesis in patients with idiopathic thrombocytopenic purpura].

This paper, used an improved methylcellulose-agar double layer method in vitro to culture megakaryocyte progenitors (CFU-meg) of 15 normal bone marrow donors and 20 idiopathic thrombocytopenic purpura (ITP) patients bone marrow cells in order to observe the action of Shen-Xue-Ling (SXL). The results showed that the colony efficiency of CFU-meg of ITP group (13.75 +/- 6.93/10(5) MNC) was obviously lower than that of the control group (21.22 +/- 9.06/10(3) MNC, P less than 0.01). The serum of the patients whose PAIgG was markedly higher than normal value inhibited growth of CFU.meg derived from normal bone marrow cells (P less than 0.01). SXL could increase the colony efficiency of CFU-meg for ITP patients at several doses. The average colonies were 15.77 +/- 6.31/10(5) MNC (at 100 mg/ml, P greater than 0.05), 18.72 +/- 5.54/10(5) MNC (at 200 mg/ml, P less than 0.05), 21.60 +/- 7.35/10(5) MNC (at 300 mg/ml, P less than 0.01) and 21.84 +/- 7.15/10(5) MNC (at 500 mg/ml, P less than 0.01) as compared with the group of ITP patients. Incubated with patient's serum (1%) and SXL (at 300 mg/ml), the number of CFU-meg extracted from normal bone marrow cells was significantly higher than that from patients (P less than 0.01) and was close to normal group (P greater than 0.05). The results suggested that SXL might inhibit the antiplatelet antibodies, facilitate reproduction, division and maturity of CFU-meg.

Adolescent↗
PubMed1990

[Surgical treatment of hilar bile duct carcinoma].

Carcinoma of the bile duct at the hepatic hilar region is not a rare condition but with a low resectability rate. The incidence of this disease seems to be on increasing. In a previous report, 60 cases were explored surgically from 1975 to 1985, but resection was only possible in 5 cases (9.1%); while in the recent years from June, 1986 to June 1989, 24 cases were explored in the Surgical Department of General Hospital of PLA, 16 cases were resected, with a resectability rate of 66%. The increase of resectability rate was due to earlier recognition of this condition and the extension of surgery, including major resection of liver as well as radical dissection of the hepato-duodenal ligament and reparative operations on the blood vessels. Among these 16 cases, major hepatic resection was performed in 10 cases, in which, 3 cases of resections of the middle lobe of the liver were done instead of right or extended right lobectomy. No operative mortality in the 30 days' postoperative period, but the postoperative morbidity rate was still high and most of the complications were related to biliary leakage and infect ion. Three patients died in the postoperative follow up period at 6.14 and 15 months respectively. All of them died from biliary infection. The remaining 13 patients were still living, the longest being 40 months and the average living time was 16.1 months. Probably, lowering of the operative mortality rate and morbidity rate are still the most important considerations in the surgical treatment of hilar carcinoma at the present time.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Effects of the pineal body and melatonin on sensitivity to pain in mice].

Sensitivity to painful stimuli was measured by hot plate, writhing tests and electric caudal stimulation in mice. The mice were kept under light-dark 12/12 cycle with light out at 18:00 for at least 2 wk. Both basal analgesia and meperidine (pethidine)-induced analgesic effect exhibited parallel circadian rhythms, with the marked peak and through occurring at mid-dark and mid-light phases, respectively. The day-night differences in pain threshold 10 d after pinealectomy were not evident, especially in the loss of dark time augmentation of analgesic responses, but persisted in sham operated mice. Melatonin (MT) 50-200 mg/kg ip during light phase produced analgesic activity. MT 250 mg/kg ip resulted in a loss of the righting reflex. In pinealectomized mice, the pre-treatment of MT 5 mg/kg potentiated levels of analgesia induced by meperidine 10 mg/kg or morphine 5 mg/kg. It is possible that MT is one of the endogenous nocifensor inhibitors in CNS.

Animals↗
PubMed1989

[Effect of triptolide on cytokinetics of HeLa cells].

The cytostatic effects of triptolide on HeLa cells in different proliferation stages and cell cycle phases were studied by colony-forming units assay. An exposure of exponential-phase cells to triptolide 0.02-4.00 micrograms/ml for 0.5 h resulted in a biphasic-exponential dose-survival curve (n = 1, D0 = 0.3 micrograms/ml in the most sensitive population; D0 = 2.8 micrograms/ml in the more resistant population). The plateau-phase cells in the same conditions seemed to have lower sensitivity to the drug. The synchronized cells caused by excess TdR double block and the selective detachment of mitotic cells from monolayer were exposed to triptolide 0.06 micrograms/ml for 0.5 h. The sensitivity of cell cycle phases to the drug ranked as follows: S greater than G2, M greater than G1. The result showed that triptolide is one of the cell cycle phase non-specific agents, but more sensitive to S phase cells.

Antineoplastic Agents, Phytogenic↗
PubMed1988

Interactions of chloride and amiloride with the renal Na+/H/ antiporter.

Amiloride is a reversible inhibitor of the Na+/H+ antiporter which acts at the external aspect of the transport system. The kinetics of inhibition of the Na+/H+ antiporter with amiloride have been controversial, with the usual finding of simple competitive inhibition, but with other reports of mixed and noncompetitive inhibition of the transporter by amiloride. The present experiments demonstrate that the chloride content of the external transport buffer affects the kinetics of amiloride inhibition. Either simple competitive or mixed inhibition by amiloride was observed in the same vesicle preparations depending on the presence of chloride or gluconate in the buffer. The effect of chloride on the inhibitory effect of amiloride was dependent on the concentration of chloride and amiloride. Similar effects were observed with more potent analogues of amiloride. These findings suggest that the external aspect of the antiporter has a site or sites at which the inhibitory effects of amiloride on the Na+/H+ antiporter can be modified by chloride, even though chloride has only slight effects on the kinetics of the Na+/H+ antiporter in the absence of amiloride.

Amiloride↗