Biomedical subjects

C Zhang

Publications and source records attributed to C Zhang.

At least 271 records · Page 15Linked to original sources

PubMed2000

[Population genetics of Chinese surnames. II. Inheritance stability of surnames and regional consanguinity of population].

This paper analyzes and compares the distributional curves and isonymy of surnames and the consanguinity of regional population in the Song and Ming dynasties and the 2 present. The distribution of surnames in the three periods reveals two significant phenomena: (1) The historical inheritance of Chinese surnames is continuous and stable. This explains why the consanguineous culture relics represented by surnames and the evolution of life substances especially Y chromosome has basically the same pattern. (2) Two types of surnames, common and rare, can be identified in China. The 100 common surnames, less than 5% of the total number of Chinese surnames, are connected with more than 85% of the population, while the rare surnames, more than 95% of the total number of surnames, are related to only about 15% of the population. The distribution of common surnames acts as the major factor reflecting the genetic composition in different regions, and it determines the historical population migration and the degree of consanguinity between regional populations. The rare surnames are of regional characteristic and relative isolation. As a result, it is possible that the study of Chinese surnames and of the distribution pattern of population with the same surname serves as an important approaches to Chinese paternal genetics and Y chromosome evolution. This may provide valuable clue for the study of population highly subject to genetic diseases.

Biological Evolution↗

PubMed2000

[Population genetics of Chinese surnames. I. Surname frequency distribution and genetic diversity in Chinese].

This paper deals with the distributional characteristics of Chinese surnames and the factors affecting their distribution. Analysis of alpha and nu values for three periods in the last 1,000 years clearly reveals the distributional pattern of Chinese surnames. In China, communities with the same surname are widespread, especially in the central areas where there are more relatively isolated Y chromosome of the same source (communities with the same surname) and more surnames than in other areas (especially the South China). If each surname has a certain kind of mono-type Y-DNA, then, according to the distribution of surnames, there exist the most mono-type of Y-DNA in the central provinces where are the originating center of Chinese surnames. For the first time, an equation is constructed predicting the kind of Chinese surnames. It has been estimated that there are about 3,100 surnames present in use for the Han nationality.

Genetic Variation↗

PubMed2000

[Study of the correlation between in vitro and in vivo evaluation methods on biomaterials--DNA test and muscular implant test].

With the wide-spread use of biomaterials, the safety evaluation on biomaterials has become a very important step. This study on the correlation between DNA test and muscular implant test was done for finding out good in vitro evaluation method. The tissue toxicities of seven biomaterials were examined. Good correlation between DNA test and muscular implant test was demonstrated by Spearman sequential correlation analysis.

Animals↗

PubMed2000

[E-selectin mediates early adhesion of HepG2 hepatoma cells to endothelial cells].

OBJECTIVE: To study the role of E-selectin and sLe(x) in the adhesion between hepatoma cells (HepG2) and endothelial cells, and to select drugs capable of inhibiting such adhesion. METHODS: HepG2 cells were vitally stained with fluorescent dye BCECF-AM. Adhesion between the fluorescent HepG2 cells and human umbilical vein endothelial cells (HUVEC) was examined by solid phase adhesion assay in vitro. A number of agents were tested for their effect on the tumor cell-endothelial adhesion. RESULTS: sLe(x) on the surface of HepG2 cells and E-selectin expressed on the surface of HUVEC were necessary for early adhesion. HepG2 cells could activate HUVEC to increase their adhesiveness to HepG2 cells. Dexamethasone, phenylarsenic oxide, levamisole and actinomycin D were able to block the adhesion between HepG2 to HUVEC at low concentrations. CONCLUSION: sLe(x) and E-selectin are important molecules in the early adhesion of hepatoma cells to HUVEC. Cytokine-like factors of HepG2 origin are likely involved in the activation of endothelial cells in the target tissue. Agents capable of inhibiting NF kappa B can be hopefuly used as anti-adhesion drugs to inhibit metastasis of liver cancer.

Animals↗

PubMed2000

Ebselen protection against hydrogen peroxide-induced cytotoxicity and DNA damage in HL-60 cells.

AIM: To study the protective effect of ebselen (Ebs) on hydrogen peroxide (H2O2)-induced cytotoxicity and DNA damage in human leukemia cell line HL-60. METHODS: The inhibitory effect of H2O2 on cell growth was determined using the tetrazolium dye colorimetric test, and the lipid peroxidation was estimated by malondialdehyde (MDA) formation. DNA damage was detected using single cell gel electrophoresis, and intracellular reactive oxygen species (ROS) formation was measured using a fluorescent probe, 2',7'-dichlorofluorescin diacetate (DCFH-DA). RESULTS: H2O2 (100 mumol.L-1) suppressed the growth of HL-60 cells and the addition of Ebs (1-20 mumol.L-1) reduced the suppression in a concentration-dependent manner. Furthermore, Ebs also displayed a concentration-dependent reduction of MDA formation in H2O2-treated cells, at the concentration of 20 mumol.L-1 the inhibitory rate was 56.4%. Ebs was able to reduce the ROS formation and DNA damage caused by H2O2 in a concentration-dependent manner. CONCLUSION: Ebs has a strong protective ability against the cytotoxicity and DNA damage caused by reactive oxygen species (ROS).

Antioxidants↗

PubMed2000

[The effect of estrogen on new bone formation in the implanted bone matrix in aged male rats].

OBJECTIVE: To study the effect of estrogen on new bone formation in the implanted bone matrix in aged male rats and on general bone metabolism. METHODS: The aged male rats were implanted with slices of bone matrix and subcutaneously injected with estrogen, androgen or the solvent for five weeks. The changes in bone histomorphometry, bio-mechanical parameters and urine deoxypyridinoline (Dpd) levels were observed as indexes of bone reabsorption. Calcium, organic phosphate, and alkalphophatase levels in serum and urine were also studied. RESULTS: (1) The areas of new bone formation were significantly larger in estrogen and androgen groups than in the control but without difference between estrogen and androgen groups. (2) The number of osteoclasts was higher in estrogen and androgen groups than in the control (P < or = 0.002) but without difference between estrogen and androgen groups. (3) Urine Dpd/Cr ratio was lower in estrogen and androgen groups than in the control and higher in the control than that obtained 5 weeks ago but without difference between estrogen and androgen groups. CONCLUSION: Estrogen and androgen are able to stimulate new bone formation in the implanted bone matrix and inhibit the reabsorption rate of systemic bones in aged male rats, but there was no difference between estrogen and androgen in these two respects under the conditions of this experiment.

Androgens↗

PubMed2000

[Effect of Bacillus megaterium on Gluconobacter oxydans in mixed culture].

To reveal the relationship between Bacillus megaterium and Gluconobacter oxydans in the mixed culture of vitamin C two-step fermentation, the effect of B. megaterium on the growth of G. oxydans and its synthesizing ability of 2-keto-L-gulonic acid(2KGA) was studied. The bioactive metabolites which could enhance the synthesis of 2KGA were isolated and purified by ultrafiltration, gel chromatography and SDS-polyacrylamide gel electrophoresis. Both the culture supernatant and the cytosol of B. megaterium could promote the proliferation of G. oxydans, and the active component in the culture supernatant was above 100 KDa. The culture suernatant could enhance the conversion of L-sorbose to 2KGA, while the cytosol could not. The active components in B. megaterium culture supernatant had molecular weight of 30-50 KDa and above 100 KDa, and the former was a kind of protein with an apparent molecular weight of about 35 KDa, which consisted of one sort of subunit and contained Fe and Zn elements.

Antibiosis↗

PubMed2000

[Effect of rice variety resistance on population dynamics of Nilaparvata lugens and Sogatella furcifera].

The effect of rice varieties with different insect-resistance on dynamics of Nilaparvata lugens and Sogatella furcifera population was examined, based on the investigation of their inhabiting ratio, egg amount, survival rate of egg and nymph, nymph development, and the amount of their offspring population. Four rice varieties, TN1, N22, AsD7 and Ptb33 were investigated. Ptb33 had a significantly lower inhabiting ratio, egg amount, and survival ratio of eggs and nymphs of both parasitic populations, a prolonged development time from nymphs to adults, and an inhibited offspring population, indicating an evident resistance of this host variety. N22 and AsD7 inhibited the development of offspring S. furcifera and N. lugens, respectively. The parasitic populations of S. furcifera and N. lugens developed more rapidly on TN1, compared with N. lugens population on N22 and S. furcifera on AsD7. The relationship between the quantitative dynamics of both population and rice variety replacement was discussed, and the possibility of using resistant rice varieties to control these two insect populations was also analyzed.

Animals↗

PubMed2000

Interventional treatment of huge hepatic cavernous hemangioma.

OBJECTIVE: To study the methods of interventional treatment of huge hepatic cavernous hemangioma (HCH). METHOD: A total of 14 patients with HCH were treated with lipiodol-ultrafluid (10-15 ml), bleomycin A (PYM 16-32 mg), and gelatin-sponge particles. RESULTS: DSA hepatic arteriography showed multiple vascular lakes in the early arterial phase, so-called "to hang the fruits on the branches", which persisted for a long time. CT scan showed a significant reduction in tumor size in 8 of the 14 patients after the treatment. CONCLUSION: Embolization with lipiodol-ultrafluid, PYM and gelatin sponge particles is one of the best methods for the treatment of HCH.

Adult↗

PubMed2000

Clinical application of radioimmunoimaging with 99mTc-BDI-1 in the diagnosis of bladder cancer.

OBJECTIVE: To evaluate the clinical application of radioimmunoimaging (RII) with 99mTc-BDI-1 in the diagnosis of bladder cancer. METHODS: 32 patients with bladder cancer and 5 with normal bladder were studied. RII was performed 1 hour after intravesical administration of 111-222 MBq 99mTc-BDI-1 followed by washing out and perfusing bladder with 50 ml PBS. The radioactivity ratio of target over background (CT/CB) was calculated. RESULTS: The radiochemical purity of 99mTc-BDI-1 was greater than 95%. RII showed radioactive accumulation area for most of bladder cancers but no radio-active concentration for normal bladder. The sensitivity and specificity were 91.7% and 81.8% respectively with the assignment of the positive criterion of CT/CB > or = 1.40. There was no statistical difference in sensitivity between tumors with diameters > or = 1 cm (1.0-4.2 cm) and < 1 cm (0.2-0.8 cm). CT/CB was related to the pathological grade (G1-G3) of the tumor. CONCLUSIONS: RII by intravesical administration provides a new noninvasive method for the diagnosis of bladder cancer in morphology and in nature of tumor with high sensitivity and specificity. It may be used for the early diagnosis of bladder cancer, follow-up after surgery, and diagnosis of in situ tumor.

Administration, Intravesical↗

PubMed2000

Effect of preoperative transcatheter arterial chemoembolization on tumor cell activity in hepatocellular carcinoma.

OBJECTIVE: To evaluate the role of preoperative transcatheter arterial chemoembolization (TACE) as a palliative approach in hepatocellular carcinoma (HCC). METHODS: From January 1992 to December 1998, 279 patients with HCC underwent curative liver resection. One to five courses of TACE prior to liver resection were performed in 117 patients (TACE group), while the other 162 patients received only liver resection (control group). All 279 specimens of resected tumors were submitted to the following assessments: PCNA and expression of P53 protein. All specimens from the TACE group were examined for downstaging or necrosis of tumors. RESULTS: In the TACE group, gross inspection revealed downstaging or necrosis of tumor in all cases. Total necrosis (100%) of tumor was observed in 11.1% of 117 patients, > 90% but incomplete necrosis in 15.4%, 50%-90% necrosis in 46.2% and < 50% necrosis in 27.3%. Microscopically, extensive and homogenous coagulative necrosis was observed. Viable cancer cells were also present within and outside the tumor capsule in 111 cases. In the remaining 6 cases, the tumor necrosed completely. In control group, necrosis was observed in 8.0% of 162 cases and reduction of tumor size was < 20%. Microscopically, viable HCC cells were noted in all cases. There was no statistical difference in expression of P53 protein between the TACE and control group. High labeling index of PCNA was significantly higher in the TACE group. CONCLUSIONS: TACE has a marked antitumor effect resulting in various degree of tumor necrosis, but only a small proportion of tumors show complete necrosis. Since the residual tumor cells following preoperative TACE may have more aggressive behavior, we conclude that sequential liver resection is the preferred therapy whenever feasible and preoperative TACE should be avoided in resectable HCC.

Adult↗

PubMed2000

[Effects of estrogen on serum lipids, plasma endothelin-1, atherosclerosis in ovariectomized rabbits].

OBJECTIVE: To investigate the effects of estrogen on serum lipids, plasma endothelin-1(ET-1) and atherosclerosis in ovariectomized(OVX) rabbits. METHODS: Forty-five female rabbits were randomly divided into 5 groups, there are 9 in each: group A: normal control; group B: sham operation + cholesterol feeding; group C: OVX + cholesterol feeding; group D: OVX + cholesterol feeding + estradiol benzoate; group E: OVX + cholesterol feeding + estradiol valerate. The OVX rabbits fed with cholesterol were used as a model for atherosclerosis. After fed for 12 weeks, all rabbits were sacrificed, and the levels of serum lipids, plasma ET-1, atherosclerosis plaque of aorta were measured. RESULTS: (1) Similar with group B, the total cholesterol (TC) of group D and E [(24.95 +/- 5.31) mmol/L and (27.53 +/- 13.18) mmol/L respectively], were significantly decreased as compared with group C which was (37.69 +/- 4.16) mmol/L. (2) The plasma ET-1 level of group C, which was (343.37 +/- 106.10) ng/L, was significantly higher as compared with group D and E, which were (262.19 +/- 36.45) ng/L [symbol: see text] (245.37 +/- 35.76) ng/L respectively. (3) There were no statistically differences of lipidic sedimentation area among group D, E, and B, which were (17.30 +/- 5.44)% and (36.99 +/- 20.29)% and (29.03 +/- 9.67)% respectively. All of them were significantly decreased as compared with group C, which was (74.83 +/- 12.58)%. CONCLUSION: Estrogen may improve the serum lipids, decrease the plasma ET-1 level, and prevent the atherosclerosis of ovariectomized rabbits.

Animals↗

PubMed2000

[Expression of MAGE-3 gene product in non-small cell lung cancer].

OBJECTIVE: To study the expression of MAGE-3 antigen in non-small cell lung cancer (NSCLC). METHODS: The expression of MAGE-3 antigen was examined in formalin fixed, paraffin embedded sections of NSCLC by LSAB immunohistochemical technique. RESULTS: MAGE-3 antigen was detected in 31 of 104 (29.8%) patients with primary NSCLC. The frequency of MAGE-3 expression was significantly correlated to the absence of metastasis (P < 0.05) and better survival rate (P < 0.01). There was no significant relationship between MAGE-3 expression and histological type of NSCLC. CONCLUSION: MAGE-3 antigen expression in NSCLC correlates with better prognosis. It is a candidate molecular target for specific immunotherapy for NSCLC patients.

Adult↗

PubMed2000

[Effect of huanyuan injection on plasma endothelin and plasma calcitonin gene-related peptide in acute intracerebral hemorrhage].

OBJECTIVE: To study the mechanism of Huanyuan injection in treating acute intracerebral hemorrhage. METHODS: Forty-five patients were divided into Huanyuan group and mannitol group who were treated with Huanyuan injection and mannitol intravenously for two weeks respectively. Meanwhile, the two groups were also treated with vitamin C, potassium chloride, etc, intravenously. Plasma endothelin (ET) and calcitonin gene-related peptide (CGRP) levels were determined before and after treatment. RESULTS: After treatment for two weeks, changes of plasma ET and CGRP in mannitol group was insignificant (P > 0.05). Compared with the two treated group, There was obvious significance in plasma ET levels and CGRP content (P < 0.05). CONCLUSION: Therapeutic mechanism of Huanyuan injection in treating acute intracerebral hemorrhage were correlated to reduce plasma ET and raise the CGRP levels.

Aged↗

PubMed2000

[Study on therapeutic mechanism of anti-rheumatism action of herba siegesbeckiae].

OBJECTIVE: To explore the mechanism of anti-rheumatism action of the active fraction of Herba Siegesbeckiae (AFHS). METHODS: Adjuvant arthritis model of rat was made to observe the effect of AFHS on lymphocyte proliferation, interluekin-1 (IL-1) and IL-2 activity, pathologic section of ankle joint, and analgesic effect of AFHS in model rat. RESULTS: AFHS could reduce the inflammatory pathologic response of ankle joint, it functions well as analgesics, the analgesic rate being 65%, AFHS could also improve T-lymphocyte proliferation, improve IL-2 activity and inhibit IL-1 activity, as compared with the control group, the difference was significant (P < 0.01). CONCLUSION: Through regulating the immune function of organism, AFHS could improve the local pathologic response so as to antagonise against rheumatism, therefore, it is a good anti-rheumatism herbal medicine.

Animals↗

PubMed2000

[Genome-wide loss of heterozygosity analyses in primary hepatocellular carcinoma].

OBJECTIVE: To investigate genome-wide loss of heterozygosity (LOH) and its clinical significance in primary hepatocellular carcinoma (HCC) in southern China. METHODS: LOH on 22 autosomes was investigated with 382 sets of microsatellite markers in 65 cases of HCC. RESULTS: The average rate of informative loci was 68.1%. More than 30% LOH was detected in loci on 17p (54.1%), 4q (48.1%), 16q (43.8%), 1q (38.3%), 8p (37.2%), 13q (33.7%), and 3p (30.8%). The frequency of LOH on D4S2964 (4q13-21) in HBsAg-positive cases was significantly higher than that in HBsAg-negative cases (P < 0.05). Cases with LOH on loci both D3S3681 (3p14-21) and D17S938 (17p13) had significantly higher rates of postoporative recurrence than those without LOH on these two loci (91% and 83% vs 52% and 65%, respectively). The 3-year survival rate was significantly lower in cases with LOH than in those without LOH on D17S938 (P < 0.05). CONCLUSIONS: LOH status in HCC patients in southern China is similar to that reported in other countries and areas. However, we first identified the high frequency of LOH on chromosome 3p in HCC. Furthermore, the infection of hepatitis B virus (HBV) may be correlated with the loss of some tumor suppressor genes on D4S2964 (4q12-13), and some tumor suppressor genes may reside on loci D3S3681 (3p12) and D17S938 (17p13), relating with tumor recurrence and prognosis.

Adolescent↗

PubMed2000

[X-linked thin basement membrane nephropathy was linked with COL4A5 gene].

OBJECTIVE: To genetically analyze 9 thin basement membrane nephropathy (TBMN) pedegrees using microsatellite marker 2B6 and DXS101 closely linked with COL4A5 gene located on chromosome X. METHODS: Genomic DNA was extracted. Highly polymorphic microsatellite markers (2B6 and DXS101) closely linked with COL4A5 gene located on chromosome X were amplified with PCR. Nine TBMN families were analysed. RESULTS: Three of 9 TBMN families were linked with COL4A5 gene on chromosome X (lod score = 2.7, theta = 0.00). CONCLUSION: X-linked TBMN is linked with COL4A5 gene on chromosome X.

Adult↗

PubMed2000

[Prevention and treatment of MODS in severely burned patients: an institute based retrospective study].

OBJECTIVE: To determine if the preventive and treatment measures developed from basic and clinical research work have any effects on the incidence and outcome of MODS in severely burned patients. METHODS: 657 extensively burned patients (burn size exceeding 30% TBSA) admitted to the clinical department from January 1970 through October 1999 were studied. The morbidity and mortality rates were compared in patient groups hospitalized before and after January 1990 when major preventive and treatment measures began to be extensively executed. These measures consisted of prompt, rapid and adequate fluid resuscitation, restoration of bowel blood supply with anisodamine (654 - 2), use of oxygen free radical scavengers (e.g. mannitol, vitamin C and E), extensive escharectomy during shock stage, early tube feeding, support of organ function, etc. RESULTS: Before 1990 when very few preventive and treatment measures were applied, the incidence of MODS, 17.3% (64 out of 369), and the death rate 87.5% (56 out of 64). After 1990, with the application of various preventive measures and treatment, the morbidity and mortality rates were reduced to 6.9% (20/288) and 40.0% (8/20), respectively. CONCLUSION: Our results suggest that measures which mitigate or eliminate the predisposing and causative factors of MODS may be salutary in the prevention and treatment of MODS after extensive burn injury.

Adolescent↗