Biomedical subjects

H Zhang

Publications and source records attributed to H Zhang.

At least 703 records · Page 39Linked to original sources

PubMed2000

[Distribution of TT virus genotypes in blood donors of northern China].

OBJECTIVE: To analyse the distribution of TT virus (TTV) genotypes in the blood donors of Northern China. METHODS: TTV DNA was detected using nested-PCR and its PCR products were cloned into the pGEM-T vector for sequencing. The sequences were analysed using ClustalX and Neighbor joining programs. RESULTS: Nucleotide identity of the 12 strains of Chinese TTV isolated was 53%-95%. Nucleotide homology between the representatives of genotype 1a and 1b [TX011(O), TA278] and the 12 strains of TTV was 55%-94% and 55%-75%, respectively. Of the 12 Chinese TTV isolates, eight were classified as genotype 1b, three as unknown genotype X and one as unknown genotype Y, which accounted for 66.7%, 25% and 8.3%, respectively. CONCLUSIONS: An exceptional degree of genetic heterogeneity was displayed in TTV nucleotide sequences and they could be, at least, classified as three genotypes. Genotype 1b may be the main prevalent genotype in blood donors of Northern China.

Amino Acid Sequence↗

PubMed2000

[Side effects after treatment with a-interferon in children with chronic viral hepatitis].

OBJECTIVE: This paper aimed at a long-term observation on side effects of alpha- IFN treatment in children with chronic viral hepatitis. METHODS: A randomized trial of 261 alpha-IFN treated chronic hepatitis children (183 with hepatitis B, 78 with hepatitis C) in comparison with 114 adults was carried out to observe side effect of alpha-IFN treatment 5-6 years in average and 10 years the longest. Mean age of children was 8.7 years, with 203 males and 58 females. RESULTS: Early stage side effects were low to moderate fever and endemic influenza symptoms, which in children were more less than in adults (P < 0.001). Side effects did not relate to viral pathogeny (HB or HC) and pathological changes (< or = G2, > or = G3) in child patient. Slightly poor appetite, slight hair loss, rash and tinnitus would disappear gradually needed no treatment. Serum Bil, Bun, Cr, T3, T4 and TSH were normal in all patients. There was no long-term side effects. CONCLUSIONS: alpha-IFN treatment for viral hepatitis in children is safe.

Adult↗

PubMed2000

Immunosuppressive effects of rubidatum in mice.

AIM: To study the effect of rubidatum (Rub) on immune function in normal mice. METHODS: Serum lysozyme concentration (SLC) was measured using micrococcus lysodiekticus as a substrate. Delayed type hypersensitivity (DTH) was determined by measuring the thickness of the right hind footpad 24 h after the injection of 1 x 10(8) washed sRBC (50 microL 10% sRBC). Serum hemolysin concentration was determined by OD measuring at A540 after the serum was treated with 2-mercaptoethanol. Phagocytic function of peripheral leukocyte (Leu) were determined by the incorporated radioactivity of [3H]TdR. The hemolytic activity of plaque forming cell (PFC) was determined by measuring the lymphocytemediated hemolysis of sheep red blood cell in vitro. T- and B-lymphocyte transformation (TLT and BLT) were induced by phytohemagglutinin (PHA) and lipopolysacharide (LPS) respectively and measured by the incorporation of [3H]TdR. RESULTS: Rub 125, 500, 2000 mg.kg-1.d-1 p.o. to BALB/c (or NIH) mice decreased the SLC; inhibited the phagocytosing functions of peripheral leukocytes; diminished the hemolytic activity of PFC; decreased the HC50; inhibited the DTH reaction; and showed inhibitory effects on TLT and BLT. CONCLUSION: Rub has immunosuppressive effects on immune system in mice by affecting M phi, T, and B lymphocyte, which suggests that Rub has inhibitory effects on both nonspecific and specific immune function.

Animals↗

PubMed2000

[Cloning and expression of full-length subtype E and subtype B gag gene from uncultured PBMCs of HIV-1 infected individuals in China].

OBJECTIVE: To clone and express subtype E and subtype B gag gene of the prevalent HIV-1 strain in China. METHODS: One HIV-1 positive sample, whose subtype had been determined as sub-type E and one HIV-1 positive sample, whose subtype had been determined as subtype B by sequence analysis of partial env gene were chosen to be amplified by nested PCR. We got two full-length fragments of gag gene and incorporated them first into plin8Pr55 and then into pFastBacl. RESULTS: Sequence analysis showed the cloned gag genes have the complete open-reading frames and have no major deletion and insertion. Using the Bac-toBac system, we obtained the recombinant baculoviruses containing gag genes. Western-blot analysis showed that insect cells infected with gag recombinant baculoviruses expressed HIV-1 gag antigen. Thin section electron microscopy showed that virus-like particles (VLPs) formed in insect cells was infected with gag. CONCLUSIONS: The cloning and expression of gag genes of the prevalent HIV-1 stains in China revealed that the cloned genes have intact structure and function and this paves the way for the development of HIV-1 vaccines targeted at the epidemic of HIV-1 in China, also for the study of biological functions of gag gene and development of diagnostic kits of HIV-1.

Animals↗

PubMed2000

[The characteristics of clinical course of chronic hepatitis B and liver cirrhosis pathology of child patient].

OBJECTIVE: To study the characteristics of clinical course of chronic hepatitis B and liver cirrhosis pathology of the child patients. METHODS: The serum test for hepatitis A/B/C/E, the liver function test and the liver puncture for pathological examination were performed in 66 child patients with chronic hepatitis B. RESULTS: The age, clinical course and form of disease onset, showed no-obvious difference between S0 group (without liver cirrhosis) and group > or = S3 (with evident liver cirrhosis). The cases with splenomegaly accounted for 2.9% in S0 group, but 32.3% in group > or = S3. The Hbe Ag positive rate of group S0 was apparently higher than that of group > or = S3 (74.29% and 29.03%, respectively). The higher the activity of liver inflammation, the more serious the extent of liver cirrhosis. CONCLUSIONS: The liver cirrhosis of child patients with chronic hepatitis B has nothing to do with their age, clinical course, form of disease onset and virus replication, but it is in direct connection with the liver inflammation activity. If splenomegaly occurs and thrombin acts abnormally, albumin in serum decreases while gamma-globulin increases, the liver cirrhosis should be highly watched out for.

Alanine Transaminase↗

PubMed2000

Plasmid DNA vaccines: assay for integration into host genomic DNA.

The primary safety concern for DNA vaccines is their potential to integrate into host cellular DNA. We describe a sensitive and quantitative assay for investigating the tissue distribution and integration of plasmid DNA vaccines. By including gonadal tissues in the analysis, the potential for germline transmission is also assessed. At various time points after injection, total DNA is isolated from a variety of tissues and assayed by PCR for the presence of plasmid. To test for integration, genomic DNA is first purified away from free plasmid using a series of different gel electrophoresis procedures. The gel-purified genomic DNA is then assayed for integrated plasmid using PCR. Stringent methods are used to prevent contamination. The assay, validated using a variety of positive and negative controls, is capable of detecting one copy of plasmid per ug DNA (approximately 150,000 diploid cells). Using this assay, we have carried out intramuscular studies in mice or guinea pigs for four different DNA vaccine plasmids. There was no evidence of integration to a sensitivity of about one copy/microg DNA, which is at least three orders of magnitude below the spontaneous mutation frequency.

Animals↗

PubMed2000

[Preliminary study on purification function of reed wetland for nutrients from land sources].

The preliminary study on purification function of reed wetland for nutrients from land sources were conducted by irrigation channels and lysimeters. The results show that the purification rates for N, P and CODcr are from 41.7%-64.71% in the channels and 60.0%-75.92% in the lysimeters. The contents of N and P reached the national second level standards of sea water after filtration by lysimeters. By harvest, the good recycle between wetland and land is formed without accumulation.

Ecology↗

PubMed2000

High frequency loss of heterozygosity in the region of the DBH locus in bladder cancer.

OBJECTIVE: To determine the location of a putative tumor suppressor gene (TSG), and evaluate the frequency loss of heterozygosity (LOH) of the long arm of chromosome 9 (9q) in bladder cancer. METHODS: We analyzed 25 patients with bladder cancer for LOH of 9q using 25 high-density microsatellite markers. RESULTS: Twenty-three samples (92%) showed LOH at least at one locus on 9q. We identified that the commonly deleted region were at 9q12-q21, 9q22, and 9q34. The rate of LOH was 44.0%, 22.7%, 22.7%, 16.0%, 12.0% on DBH, D9S15, D9S1815, D9S1831, D9S176 locus, respectively, and was not significantly related with grades and stages of tumor. CONCLUSION: These data suggest that alteration of a TSG at DBH of 9q may play an important role in the development of bladder cancer.

Chromosomes, Human, Pair 9↗

PubMed2000

Effect of hormone replacement therapy on heart rate variability in postmenopausal women.

OBJECTIVE: To assess the characteristics of autonomic control of heart rate in postmenopausal women before and after hormone replacement therapy (HRT). METHODS: Time domain and spectral domain heart rate variability (HRV) were performed in 58 postmenopausal women before and after HRT. RESULTS: Compared with examinations at baseline, values of all HRV measurements in subjects given HRT were increased at the fourth month (P < 0.05), while they remained unchanged in the control group (P > 0.05). Results showed an inverse correlation between all measures of HRV and mean R-R interval in the treatment group. CONCLUSION: HRT reduces sympathetic drive in postmenopausal symptomatic women. HRV may be an index of imbalance of autonomic control in perimenopausal women.

Autonomic Nervous System↗

PubMed2000

Vitamin D receptor gene polymorphism in postmenopausal women of the Han and Uygur nationalities in China.

OBJECTIVE: Polymorphism in vitamin D receptor (VDR) gene has been reported to play a major role in variations for genetic regulation of bone mass. Its role within various ethnic populations is not clear. The purpose of this study was to determine the frequencies of VDR genotypes in the Han and Uygur nationalities in China. METHODS: We analyzed the polymorphism of Bsm I restriction enzyme by PCR-RFLP technique in 162 healthy postmenopausal women of the Han nationality and 50 healthy postmenopausal women of the Uygur nationality in China. The genotype frequencies of VDR were calculated using Hardy-Weinberg equilibrium formula. RESULTS: In the Han nationality, the bb, Bb, and BB genotype accounted for 91.36%, 8.64% and 0%, respectively. In the Uygur nationality, frequencies were 74.00%, 18.00% and 8.00%, respectively. CONCLUSION: There was a significant difference between the Han and Uygur nationalities in the frequency distribution of VDR genotype (P < 0.01). Compared with the Caucasian population in the United States, Australia and France, there was a similar value to Uygur nationality in the BB genotype. This investigation gave us further evidence on the different etiopathology of osteoporosis in various ethnic groups.

Alleles↗

PubMed2000

Interaction of alcohol and the G to a substitution at the promoter region of the apolipoprotein AI gene in determining plasma apolipoprotein AI levels in Yi and Han Chinese.

OBJECTIVE: To investigate the influence on plasma lipid levels of alcohol and a common polymorphism in the human apolipoprotein AI gene promoter at a position 75 bp upstream of the transcription start site. METHODS: For this study, 742 healthy Yi and Han subjects all above 15 years old formed the total population which was divided into three groups: the Yi-farmer group, the Yi-emigrant group and the Han-resident group. All estimates of plasma lipids and apolipoproteins were performed using an auto-analyzer. Genetic DNA was prepared from the blood clots using the Triton X-100 lysis technique. Amplification of a 432 bp fragment of the apoAI gene promoter was performed using PCR followed by restriction digestion, electrophoresis and identification of the genotypes involved. RESULTS: The samples were divided on the basis of alcohol consumption: non-drinkers, 1-25 g/day, 26-75 g/day and > 75 g/day. Comparing the four alcohol consumption groups, plasma HDLC and apoAI levels were increased as the alcohol consumption increased with no evidence of threshold effects in the Yi-farmers and the Han people groups. A similar association was found in the Yi-emigrant group, but was not statistically significant. The frequencies of the A allele in the three populations were similar, and no significant difference of lipid and apolipoprotein levels was found between subjects with and without the A allele in the three populations. But, in Han and Yi-emigrant samples, the drinkers with the GG genotype had higher plasma HDLC and apoAI levels than non-drinkers with the same genotype, while the drinkers with the A allele had lower plasma HDLC and apoAI levels than drinkers without the A allele. Non-drinkers with the A allele had higher levels of apoAI than non-drinkers with GG genotypes. It was estimated that 18% of the variability of plasma apoAI level could be explained by the G to A polymorphism in non-drinkers of Yi-emigrants (F = 8.94, P < 0.01). CONCLUSIONS: The present data suggest that moderate alcohol consumption and the G to A substitution could lower the risk of coronary heart disease (CHD), but the beneficial effects of one will be negated by the other.

Adolescent↗

PubMed2000

Changes in systemic and splanchnic hemodynamics after orthotopic liver transplantation in cirrhotic rats.

OBJECTIVE: To investigate early changes in systemic and splanchnic hemodynamics after orthotopic liver transplantation (OLT) in normal and cirrhotic rats. METHODS: Male Sprague-Dawley rats were divided into 4 groups: normal controls (NL, n = 10), intrahepatic portal hypertension (IHPH, n = 10) induced by injection of CCl4, normal rats with OLT (NL-OLT, n = 9) and IHPH rats with OLT (IHPH-OLT, n = 16). IHPH-OLT rats were divided into 2 subgroups: 3 days (Group A, n = 9) and 7 days (Group B, n = 7) after OLT. OLT was performed in rats using cuffs for the anastomosis of the suprahepatic inferior vena cava, infrahepatic vena cava and portal vein. Two weeks after production of IHPH rats, 7 days after NL-OLT rats, 3 days and 7 days after IHPH-OLT rats, radioactive microspheres were used in a hemodynamic study. RESULTS: There were no significant differences in hemodynamic changes between NL-OLT and NL rats, except mean arterial blood pressure (MAP). The characteristics of systemic and splanchnic hyperdynamic circulatory state, including increased cardiac output and splanchnic blood flow, decreased mean arterial blood pressure, total peripheral vascular resistance and splanchnic vascular resistance were observed in IHPH, IHPH-OLT A, and IHPH-OLT B rats. The magnitude of hyperhemodynamics was in the order of IHPH > IHPH-OLT A > IHPH-OLT B rats. Moreover, the derangement of splanchnic hyperhemodynamics was more significant than that of systemic hyperthermodynamics. CONCLUSIONS: The present study demonstrates that the persistence of early systemic and splanchnic hyperkinetic circulation after OLT may be the consequence of factors which maintain hyperhemodynamics in liver cirrhosis, where portal hypertension is not completely eliminated. Hyperhemodynamics is not induced by OLT per se.

Animals↗

PubMed2000

[In vitro studies on dendritic cell derived from cord blood and its role in antitumor immunity].

OBJECTIVE: To investigate the way of inducing dendritic cell (DC) from precursor in cord blood and its role in antitumor immunity. METHODS: Cord blood was collected under sterile condition and the mononuclear cells (MNCs) were separated by centrifugal in density gradient (Ficoll-Hypaque). The adhesion cells, collected among the MNCs, were cultured with interleukin-4 (IL-4, 50 ng), granulocyte-macrophage colony-stumilating factor (GM-CSF, 100 ng) and tumor necrosis factor alpha (TNF-alpha, 1-2 ng) in dulbecco's modified eagles medium (DMEM) medium. Cell phenotype was analyzed on 10th day with CD1a, CD16, CD14, CD19, CD40, CD56, CD80, CD83, and human leukocyte antigens-D-related (HLA-DR) antibody by using indirect immunofluorescence assays. After cultured with tumor cytolysis antigen for 2 days, the cells were incubated with auto T cell separated by E-rosette formation. Methyl thiazolyl tetrazolium (MTT) assay was employed to test inhibition rate of tumor specific cytotoxic T lymphocyte (CTL) on HO9810 tumor cell line. RESULTS: Our results indicated that DC precursors in cord blood can be induced to differentiate and mature in the medium containing IL-4, GM-CSF, and TNF-alpha. Some DC specialized antigens expressions were seen on 10th day after cultured with cytokines. After incubation with tumor cytolysis antigen, the DC can activate the CTL to become tumor specialized CTL, which had shown significantly inhibition on growth of HO9810 tumor cell line. CONCLUSIONS: Primary in vitro experiment has shown that the precursors in cord blood can be induced to functional DC which activate T lymphocyte to become tumor specialized CTL. Our result indicate that it is an efficient and convenient way in antitumor immunity by inducing DC precursors in cord blood to functional DC and may have a great implication on clinical application.

Antigens, Neoplasm↗

PubMed2000

[Safety evaluation of Ad-ASmyc in vitro and in vivo].

OBJECTIVE: To assess the safety of adenovirus-mediated transfer of anti-sense c-myc (Ad-ASmyc). METHODS: RT-PCR was used to detect the transcription of Ad-ASmyc in HeLa cells infected with extracts from HeLa cells previously infected with Ad-ASmyc. Cell count was used to observe the effects of Ad-ASmyc on the growth of normal human fetal lung diploid cell line 2BS. Ad-ASmyc was given to 2 groups of Balb/c mice by intraperitoneal injection at a dosage of 10(7) pfu and 10(9) pfu respectively. Blood samples were obtained from the mice for liver and renal function tests. PCR was used to screen the vital organs for the presence of adenovirus DNA. Microscopic examination of the vital organs was performed to observe the pathogenicity of Ad-ASmyc. RESULTS: As a replication-defective virus, Ad-ASmyc could infect 2BS cells effectively, but did not inhibit 2BS cell growth. No mouse died and no signs of general toxicity following intraperitoneal injection of Ad-ASmyc were observed. In mice injected with 10(9) pfu Ad-ASmyc, the adenoviral vector was found in the liver, spleen, kidney, and stomach. On day 6 and day 12 after injection, mild inflammatory infiltration of mononuclear cells was observed. CONCLUSION: The use ofadenoviral vector for antisense c-myc gene transfer in vitro and in vivo is considered to be safe for clinical trial.

Adenoviridae↗

PubMed2000

[Quantitative 3D measurements of the skull base by using spiral volumatric CT images].

OBJECTIVE: To study the spatial relationships of mandibular condyle and carotid canal, jugular fossa, foramen ovale, foramen spinosum when mandible in normal physical position. METHODS: 100 native adults were examined by spiral volumatric CT. The data were transferred to workstation, three-dimensional(3d) cranial base images were reconstructed, 3D measurements were performed by using specific 3d CT landmarks. 12 points were defined and 28 distances and angles were measured in the skull base from submandibular viewpoint. The internal pole of condyle and the condylar long axis were regarded as the center point and 0 degree axis in the reference frame. RESULTS: Submandibular approach provided a clear vision of the internal pole of condyle and condylar long axis. The ECC was located at 12.01 +/- 2.71 mm, 5.14 +/- 1.22 degrees, Jug was located at 15.11 +/- 2.72 mm, -56.27 +/- 14.05 degrees according to the reference frame. CONCLUSIONS: Quantitative measurements of 3D skull base can be very precise. Mandibular approach is easy to show the mandibular condyle. The reference frame is helpful to located other important structures of skull base in operation.

Female↗

PubMed2000

[The research of a multimedia consultative system for prosthodontics].

OBJECTIVE: To study how to develop the consultative multimedia system for prosthodontics facilitating the communication between the dentists and patients, using multimedia techniques. METHODS: The Founder Author Tools V2.1 was used to develop the consultative system in the Pwin95/98 environment. Many forms (such as the articles, pictures, sound and video) of the prosthodontic knowledge were edited in this system. RESULTS: The consultative multimedia system for prosthodontics was developed, and there were three main parts of the system: (1) the background of medical departments, (2) introductions of the medical specialists (including their photos and working time), (3) introducing the common acknowledge of prosthodontics. CONCLUSION: The visualization of the prosthodontic problems consulted by patients frequently can facilitate the communication between the dentists and patients and spare visit time. This system are welcome by the patients.

Communication↗

PubMed2000

[Significance of amnioinfusion and amniotic fluid exchange under continuous internal fetal heart rate monitoring for management of fetal distress during labor].

OBJECTIVE: To discuss the significance of amnioinfusion and amniotic fluid exchange under continuous internal fetal heart rate (FHR) monitoring for management of fetal distress during labor. METHODS: 136 cases with frequent variable deceleration (VD) and meconium stained amniotic fluid during labor were divided into two groups: the study group (68 cases) and the control group (68 cases). The former were treated by amnioinfusion and amniotic fluid exchange, while oxygen inhalation, change of body position, and intravenous infusion for the control group. RESULTS: In the study group, VD disappeared or relieved in 62 cases obviously, and the efficacy rate reached 91.2% (62/68). 48 cases with II degree meconium stained amniotic fluid were treated by amniotic fluid exchange, amniotic fluid became clear or turned to I degree stained in 39 cases. In the control group, VD relieved in 20 cases, the efficacy rate was 19.4%, significantly lower than that of the study group (P < 0.01). In the study group, cesarean section rate was 14.7% neonatal asphyxia 7.4% while they were 47.1% and 48.5% in the control group respectively (P < 0.01; P < 0.01). Neonatal pneumonia caused by meconium aspiration occurred in 13 cases, meconium aspiration syndrome (MAS) 8 cases, with 5 newborns died in the control group, while there was no neonatal death in the study group. There was no significant difference on puerperal morbidity between the 2 groups (P > 0.05). CONCLUSIONS: Amnioinfusion and AF exchange during labor are one of the effective treatment methods for fetal distress and prevention for MAS.

Adult↗

PubMed2000

[Clinical types of pheochromocytom].

OBJECTIVE: To improve the diagnosis and treatment of pheochromocytoma. METHODS: 90 patients with pheochromocytomas were treated from June 1987 to August 1998. These patients showed extra-adrenal (14 patients), non-symptomatic (5), recurrent (8), malignant (15), bilateral or multiple (4), and familial or MEN-IIA (5). RESULTS: One patient with malignant extra-adrenal pheochromocytoma showed extensive metastasis. All the patients except this patient were confirmed pathologically. 36 patients were followed up for 5 months - 10 years. Eight patients had recurrence and 3 showed malignancy. CONCLUSIONS: Open surgery is an effective method for pheochromocytoma. Preoperative preparation must be sufficient to make the operation safe. Recurrent pheochromocytomas are not malignant in nature, but they have considerable malignant tendency and should undergo intensive surveillance and regular examinations. Familial pheochromocytomas are bilateral or multiple. They could develop into secondary medullar thyroid carcinoma in the meantime.

Adolescent↗