Biomedical subjects

H Zhao

Publications and source records attributed to H Zhao.

At least 217 records · Page 12Linked to original sources

PubMed2000

[Influence of plant species diversity on productivity of sandy grassland in Kerqin Region].

The relationship between species diversity indices and sandy grassland productivity was studied in Kerqin sandy land, and the results showed that the relations could be divided in to two categories based on the indices and productivity. The first type includes function and composition diversities, their maximal biomass varied form 299 to 336 g.m-2, and had a simple linear relation with the productivity. Their correlation coefficient was remarkably significant. The species richness and Shannon-Wiener indices attribute to second type, their maximal biomass varied from 426 to 433 g.m-2, and had a complex parabola relations with the productivity. Their correlation coefficient was also significant. Meanwhile, the grey correlation analysis showed that the species composition diversity index was the most important factor that influences productivity. According to the grey correlation degree, the order of the different indices affecting productivity was: composition diversity(0.74), function diversity (0.72), species richness (0.66) and Shannon-Wiener index (0.14). It is suggested that increasing plant species richness (species introduction) and consequent composition diversity could be the practices of improving the degraded grassland in Kerqin.

Biomass↗

PubMed2000

Synergetic effect of dialyzer membrane and lipopolysaccharide on peripheral blood mononuclear cell cytokine production in uremic patients.

OBJECTIVE: To investigate the effect of lipopolysaccharide(LPS) and dialyzer membrane on cytokine gene expression and protein production in uremic patients on continuous ambulatory peritoneal dialysis (CAPD) and regular hemodialysis(HD). METHODS: Interleukin-1 beta (IL-1 beta) and interleukin-1 receptor antagonist (IL-1Ra) produced by cultured peripheral blood mononuclear cells (PBMC) after exposure to cuprammonium (Cup) membrane, polysulfone (PS) membranes or endotoxin were detected using enzyme-linked immunoabsorbent assay. mRNA expression was determined simultaneously by in situ hybridization. RESULTS: In the absence of endotoxin, a small amount of IL-1 beta and IL-1 Ra was produced by PBMC harvested from HD and CAPD patients after incubation with Cup or PS during subsequent 24-hour culture. For healthy controls, IL-1 beta was barely detectable just above the detection limit. Although no differences could be found in protein synthesis between Cup and PS, in situ hybridization showed that Cup induced markedly higher level mRNA coding for IL-1 beta and IL-1Ra. In contrast, when subsequently stimulated with endotoxin, PBMC incubated with Cup could produce significantly larger amount of IL-1 beta and IL-1Ra compared with either unstimulated cells or post-incubation PBMC with PS. LPS-stimulated PBMC in healthy subjects produced similar amount of IL-1 beta and markedly lower IL-1Ra as compared with uremic patients on HD and CAPD. CONCLUSIONS: Two steps are required in healthy control for IL-1 beta and IL-1Ra production: induction of mRNA transcription by membrane contact, followed by LPS-induced translation, while in uremic patients on HD or CAPD bioincompatibility-membrane and LPS have a synergetic effect on IL-1 beta and IL-1Ra production. There exists an unbalance between IL-1 beta and its specific inhibitor in maintenance dialysis patients.

Adult↗

PubMed2000

Detecting residual ischemia and identifying coronary artery disease after myocardial infarction using dobutamine technetium-99m-MIBI SPECT.

OBJECTIVE: To evaluate dobutamine technetium-99m methoxy isobutyl nitrile (sestamibi) single-photon emission computed tomography (Dobu-ECT) in detecting residual ischemia and identifying coronary vessel disease after myocardial infarction. METHODS: Sixty-two patients with confirmed myocardial infarction were studied with Dobu-ECT at the time of coronary artery angiography. Dobutamine was administered intravenously in incremental rates from 5 to 40 micrograms.kg-1.min-1 at 3-minute intervals. At the highest infusion rate, 7.4 x 10(8) Bq 99mTc-MIBI was injected intravenously, and tomographic imaging was performed after one hour. Resting images were taken after 24 hours, with a second dose of 99mTc-MIBI. RESULTS: The sensitivity of Dobu-ECT in detecting residual ischemia of myocardial infarction was 76%, which was higher than dobutamine electrocardiography (Dobu-ECG). Regardless of the single-, double- or triple-vessel diseases, Dobu-ECT was superior to Dobu-ECG in identifying residual ischemia (56% vs 4%, 86% vs 27%, 100% vs 47%, P < 0.01, respectively). The incidence of residual ischemia in patients receiving thrombolytic therapy was 67%, lower than patients without thrombolysis (72%) or those with an old myocardial infarction (94%). But the differences were not statistically significant. Dobu-ECT detected only 56% of ischemias in non-infarct related myocardium. Eighty-two percent of all significantly stenosed vessels were detected with Dobu-ECT, and 84% of patients with multivessel disease could be accurately identified. The sensitivity of Dobu-ECT was significantly greater for detecting severe stenosis over moderate stenosis. The sensitivity for detecting stenosis in the right coronary artery was greater than left anterior descending or left circumflex, but its specificity was lower. CONCLUSION: Dobu-ECT can identify residual ischemia, as well as its location and extent after myocardial infarction. Dobu-ECT can also accurately detect significantly stenosed vessels.

Adult↗

PubMed2000

Relationship between the renin-angiotensin system genes and diabetic nephropathy in the Chinese.

OBJECTIVE: To clarify whether genetic variants of the renin-angiotensin system (RAS) contribute to the development of diabetic nephropathy (DN) in the Chinese. METHODS: Totally 173 Chinese subjects of Han nationality from Shanghai were classified into! control, DN (-) and DN (+) groups. The latter was subdivided according to diabetic duration at the onset of DN and the stage of DN. Genotyping of five polymorphic sites in four key genes of the RAS: the AGT-T174M, AGT-M235T and AGTR1 genotypes were determined by PCR/restriction enzyme digestion. The insertion/deletion (I/D) and [ACAC] n-STR microsatellite polymorphic markers were used for ACE and REN genotyping, respectively. Statistical analysis showed comparisons of gene frequencies between any two groups were made with Fisher's exact test or Chi-square test. Logistic regression analysis was performed to identify predictors of DN. RESULTS: The frequencies of ACE-DD genotype and ACE-D allele were much higher in DN(+) group than in DN (-) group (0.25 vs 0.05, 0.47 vs 0.29, respectively), so were the frequencies of TT genotype and T allele in AGT-M235T (0.73 vs 0.54, 0.85 vs 0.68, respectively). DN (+) DUR < 5 years group had greatly increased frequencies of AGT-M235T allele and ACE-DD genotype in comparison with DN(-) group (0.92 vs 0.68 and 0.28 vs 0.05, respectively). Logistic regression analysis further identified these two genes as contributing factors to DN. Although AGTR1 and AGT-T174M genotyping analysis revealed differences in frequency distribution between DN (+) and DN (-) or control groups, logistic regression analysis failed to implicate them in the development of DN. CONCLUSIONS: Our study revealed RAS genes, ACE and AGT-M235T but not AGT-T174M, AGTR1 or REN genotypes, as contributing factors for DN in type 2 diabetes mellitus in Chinese.

Aged↗

PubMed2000

Expression of the MAGE-1 gene in human hepatocellular carcinomas.

OBJECTIVE: To further investigate the expression of MAGE-1 gene in hepatocellular carcinoma (HCC). METHODS: The tumors and adjacent liver tissue from 45 HCC patients and liver tissue from 28 non-HCC patients (16 with liver cirrhosis and 12 with normal liver) were characterized by RT-PCR. A 421 bp PCR product from a cDNA fragment spanning exons 1, 2 and 3 was sequenced. The HLA type was assayed by standard ELISA in 43 HCC patients. RESULTS: Thirty-two of 45 tumor tissues from HCC patients expressed MAGE-1 mRNA (71.1%). In contrast, MAGE-1 mRNA was not detected in adjacent tissues. Three were found to have point mutations at 3 identical sites resulting in the substitution of two amino acid residues. The most frequent HLA types in 43 HCC patients were: HLA-A2, 53.5%; A11, 25.6%; A24, 20.9%; A33, 20.9%; HLA-B13, 28.3% and B35, 23.2%. Expression of HLA-A33 (20.9%) was higher in HCC patients than that predicted in the normal Chinese population (8.8%). There was no discemable correlation between MAGE-1 expression and alpha-FP level, tumor size and hepatitis B or C virus infection. The identification of peptides which are restricted by haploptypes other than A1 should increase the opportunity for peptide based immunotherapy. CONCLUSIONS: This study shows that MAGE-1 mRNA is highly expressed in HCC tumor tissue in Chinese patients. Previously unreported point mutations in the MAGE-1 gene are described and may also provide additional opportunities for immunotherapy.

Amino Acid Sequence↗

PubMed2000

[Changes of tumor necrosis factor alpha and interleukin-6 levels in peritoneal fluid of patients with endometriosis and their effects on human sperm motility and mouse embryo development].

OBJECTIVE: To study the changes of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) levels in peritoneal fluid of patients with endometriosis and their effects on human sperm motility and mouse embryo development. METHODS: Levels of TNF-alpha and IL-6 in peritoneal fluid and cultured peritoneal macrophages supernatant were detected by enzyme-linked immunoassay (ELISA) in 14 infertile patients (EMT group) with endometriosis proven by laparoscopy and 11 infertile women with normal pelvic organs (control group). The effects of peritoneal fluids obtained from the 2 groups on human sperm motility and development of 2-cell mouse embryo were also studied in vitro. RESULTS: In EMT group the numbers of peritoneal macrophages were higher than those in the control group. Levels of TNF-alpha [(0.33 +/- 0.15), (7.19 +/- 0.60) micrograms/L] and IL-6 [(0.49 +/- 0.68), (1.51 +/- 0.08) micrograms/L] in peritoneal fluid and peritoneal macrophage supernatant were also elevated significantly as compared with those in the controls (P < 0.01). Meanwhile, after four-hour incubation with peritoneal fluids, the percentage of straight-line moving sperm and total sperm motility rate were decreased significantly in EMT group(P < 0.01). Appearance rate of 16-cell mouse embryo was 32.5% in EMT group versus 47.6% in control group after 48 hour coculture with peritoneal fluids(P < 0.01). CONCLUSION: It is likely that elevation of peritoneal fluids cytokines levels in patients with endometriosis may play a role in the pathogenesis of infertility associated with endometriosis.

Animals↗

PubMed2000

[In vitro effect of danazol on cytokine production of macrophages in peritoneal fluid of infertile patients with endometriosis and its relationship with cytosolic free calicum concentration].

OBJECTIVE: To investigate in vitro effect of danazol on cytokine production of macrophages in peritoneal fluid from infertile patients with endometriosis and its relationship with cytosolic free calicum ([Ca2+]i) concentration. METHODS: Pertitoneal macrophages were obtaind from 14 cases of 24 infertile women with endometriosis (EM group) and 11 cases of 19 infertile women with normal pelvis (control group). Danazol was added to peritoneal macrophages culture reaching final concentrrations of 10 micrograms/L, 100 micrograms/L, 1,000 micrograms/L respectively. Tumor necrosis factor alpha(TNF-alpha) and interleukin-6 (IL-6) levels in macrophage supernatant were detected by enzyme linked immunoassay. The [Ca2+]i of cultured peritoneal macrophage and its changes after danazol addition were also studied. RESULTS: In EM group TNF-alpha and IL-6 levels in peritoneal macrophage supernatant and [Ca2+]i of macrophages were elevated significantly as compared with those in control group. When danazol was added to the cell culture and reached 100 micrograms/L of concentration, the levels of TNF-alpha and IL-6 in cultured macrophage supernatant and the [Ca2+]i of macrophages in EM group decreased significantly (P < 0.01). CONCLUSION: It is suggested that danazol may exert its suppressive effect on endometriosis by inhibiting cytokine release of peritoneal macrophages and may related to decline of [Ca2+]i concentration.

Adult↗

PubMed2000

[Effect of fixed appliance on periodontal status of patients with malocclusion].

OBJECTIVE: To determine if the fixed appliance will affect the periodontal health. METHODS: Sixteen patients with malocclusion were randomly selected. One week before the fixed appliance placement, plaque index (PLI), bleeding index (BI), pocket depth (PD) and subgingival plaque were assessed. The observed value was served as the baseline records. RESULTS: After the fixed appliance placement, significant differences were found in PLI, BI, PD and these values were significantly greater than the baseline. Subgingival microfloral shifted to a more disease-inducing microflora and there was a statistically significant increase in spirochetes and fusiform. CONCLUSION: Fixed appliance placement will affect the periodontal health. Therefore, it is very important to strengthen the oral hygiene instruction to the people who receive the treatment of fixed appliance.

Adolescent↗

PubMed2000

[Cardiac protective effects of tetramethylpyrazine in patients performed open-heart operation with cardiopulmonary bypass].

OBJECTIVE: To study the cardiac protective effects of tetramethylpyrazine (TMP) on patients undergoing cardiac operation. METHODS: Twelve patients with rheumatic heart disease were randomly divided into the TMP group and the control group, 6 in each group. The changes of hemodynamics, serum creatine phosphokinase (CPK), creatine phosphokinase isoenzyme (CPK-MB) levels were observed before, during and 72 hours after operation. RESULTS: The hemodynamic indexes in the TMP group were better than those in the control group after operation, the serum CPK, CPK-MB levels measuring 12 h, 24 h and 48 h after operation in the TMP group were lower than those in the control group. CONCLUSION: TMP has good cardiac protective function in patients undergoing cardiac operation in improving cardial function and reducing the release of myocardial enzymes.

Adult↗

PubMed2000

[Vascular endothelial factor of meningomas and peritumoural vasogenic brain edema].

OBJECTIVE: To study the expression of vascular endothelial growth factor (VEGF) in meningomas correlated with peritumoral vasogenic brain edema (PVBE) and angiogenesis. METHODS: VEGF protein expression in 33 patients with meningomas (12 men, average 50 +/- 12 years; 21 women average 46 +/- 14 years) was examined by immunohistochemical and western blotting. The number of microvessels which were immunostained with von willelrand factor was counted and PVBE was assessed blindly before MRI scan or CT scan. RESULTS: The expression of VEGF protein was found in 75.8% (25/33). The mean rate of immunostaining was 2.03 and the mean rate of PVBE was 2.39. The rate of staining intensity was correlated with PVBE rate (r = 0.7352, P < 0.01) and vascular counts (r = 0.6974, P < 0.01). VEGF protein isoform of molecular sizes corresponding to VEGF165 was detected in cytosolic extracts of meningomas. CONCLUSIONS: VEGF is highly related to PVBE and angiogenesis of meningoma. Wide-spread distribution of VEGF in meningomas suggests VEGF165 isoform.

Adolescent↗

PubMed2000

[Ultrasonically guided radio-frequency ablation of liver tumors with a clustered electrode: a report of 100 cases].

OBJECTIVE: To evaluate the efficacy of ultrasonically guided radio-frequency (RF) thermal ablation of liver tumors with a clustered electrode. METHODS: Clinical records of 100 consecutive patients who underwent RF tissue ablation 120 times were analysed. Image data, tumor size, clinic manifestation, and AFP value before and after the procedure were compared. RESULTS: A hundred cases at 10 days, thirty at 30 days, ten at 60 days after the procedure were subjected to color ultrasonography and CT scans, respectively. The tumor size decreased by 20% at 10 days in 70% patients, decreased by 30% at 30 days in 80% patients, decreased by 50% at 60 days in 3 patients. AFP value decreased in 50% of patients, no operative death was noted, and the rate of operative complication was 23% after ablation. CONCLUSION: Ultrasound guided RF thermal ablation of hepatic tumors is safe, applicable and effective.

Adolescent↗

PubMed2000

[Melanoma antigen-3 expression in human hepatocellular carcinoma].

OBJECTIVE: To investigate the expression of melanoma antigen-3 (MAGE-3) mRNA in human hepatocellular carcinoma (HCC) and probe into the theoretical feasibility that MAGE-3 antigens can be developed as a new peptide vaccine for immunotherapy in HCC patients. METHODS: The expression of MAGE-3 mRNA in HCC tissues and the adjacent non-HCC liver tissues was studied using RT-PCR in 45 HCC patients. The results were compared with those of 16 cirrhotic patients and 12 patients whose liver tissues were pathologically normal. MAGE-3 mRNA positive PCR products were DNA sequenced in 3 HCC patients. The sequenced fragments of MAGE-3 cDNA were used as template by which a [alpha(32)P] labeled probe was synthesized and employed for Southern blot analysis. HLA class I-A and -B typing of 43 HCC patients were assayed by ELISA. RESULTS: Of the 45 HCC samples, 35 (78%) expressed MAGE-3 mRNA and six HCC adjacent tissues were also positive in MAGE-3 expression. Pathological examination showed cellular heteromorphism in these adjacent tissues. The non-HCC liver tissues from cirrhosis and normal liver samples were not MAGE-3 mRNA detectable. The DNA sequence confirmed that the target gene fragment in all of the 3 samples of PCR products was MAGE-3 cDNA. Southern blotting result confirmed that of RT-PCR assay. In HCC patients, the predominant types of HLA were A(2) (53.5%), A(11) (25.6%), A(24) (20.9%), A(33) (20.9%), B(13) (28.3%), and B(35) (23.2%). MAGE-3 mRNA expression in HCC showed no correlation with the level of serum AFP and the size of the tumor. CONCLUSIONS: MAGE-3 mRNA is expressed at a high percentage of HCC samples. This tumor rejection antigen may be used as peptide vaccine for immunotherapy of HCC patients. The phenomena that some non-HCC adjacent tissues with heteromorphism can express MAGE-3 like their paired HCC tissues indicate that the expression of MAGE-3 may be an indicator in the early stage of carcinogenesis of liver tissues.

Aged↗

PubMed2000

[Analysis of hepatitis G virus genotypes in some areas of China].

OBJECTIVE: To study the genotype distribution of hepatitis G virus (HGV) isolated from different population in some areas of China. METHODS: A total of 12 strains of HGV were isolated from different areas of China (three from Guangxi Zhuang Autonomous Region, three from Hebei Province, one from Heilongjiang, Jiangxi, Guangdong, Jiangsu, Anhui, Jilin Provinces and Xinjiang Autonomous Region each). The HGV 5' untranslated region (UTR) of the 12 isolates was sequenced and compared with other 26 isolates previously reported (17 from China and nine from other countries). RESULTS: The nucleotide sequences of five HGV clones isolated from the same patient with HGV infection were identical, with the homology of 99.1% - 100%, indicating that variation of HGV in the same human body was very limited. Genotyping could be based on the sequence of one positive clone isolated from a patient with HGV infection. The homology of the nucleotide sequences in the 12 isolates was 96.8% - 99.4%, suggesting that they belonged to the same genotype. The homology of the 12 isolates was 88.0% - 89.7%, 87.2% - 90.3% and 94.7% - 96.3%, respectively, as compared with HGV genotypes 1 (U36380), 2 (U44402) and 3 (D90601), which indicated that all the 12 HGV isolates belonged to genotype 3. Phylogenetic distance analysis of the 38 isolates suggested that HGV strains isolated from China could be further divided into different subgroups. CONCLUSION: The majority of Chinese HGV isolates belonged to genotype 3 and they could be further divided into different subgroups.

Base Sequence↗

PubMed2000

[Effect of sodium fluoride on bone turnover and bone loss of vertebrae and tibia in ovariectomized rats].

OBJECTIVE: To investigate the effect of sodium fluoride on bone turnover and bone loss of vertebra and tibia of ovariectomized rats. METHODS: 34 female Wistar rats, 16 weeks old, were divided into 3 groups: sham-ovariectomy (CON), bilateral ovariectomy (OVX) and both OVX and NaF-treatment groups (OVX + NaF, 1.0 mg/kg BW). All of the rats were sacrificed 12 weeks after the treatment. Serum was collected for the analysis of estradiol, calcium, phosphorum and alkaline phosphotase. Temur was used for the analysis of calcium content. Tibiae and the first lumbar vertebral bodies were decalcified for histomorphometry. RESULTS: After treatment with NaF, bone resorption was not inhibited, but bone formation was significantly increased. The trabecular bone volume of vertebrae (18.73% +/- 3.04%) and tibiae (14.30% +/- 5.87%) was significantly increased in comparing with of OVX rats (15.07% +/- 2.45% and 8.81% +/- 2.60%, P < 0.05), but it was markedly lower than that of CON rats (22.44% +/- 1.82% and 24.87% +/- 4.02%, P < 0.05 and P < 0.01). CONCLUSIONS: NaF could not decrease bone turnover and it, has only a partial protective effect against bone loss of either vertebra or tibia.

Animals↗

PubMed2000

[Effects of heat and noise environments on lipid peroxidation erythrocyte membrane in pilots].

OBJECTIVE: To investigate the effects of heat and noise environments on lipid peroxidation of erythrocyte membrane in pilots. METHOD: Twenty-four pilots and twenty-one ground personnel (control group) served as the subjects. The pilots performed flying in heat and noise environments. Glutathione peroxidase (GSHpx) and malondialdehyde [correction of malondiadehyde] (MDA) levels in erythrocyte membrane were determined before flying (6:00 a.m.), immediately after flying (12:00 a.m.) and 8 hours after flying (8:00 p.m.) respectively with a spectrophotometer. RESULT: Immediately after flying, GSHpx activity in pilot's erythrocyte membrane decreased significantly as compared with that in control group. Immediately after flying and 8 h after flying, MDA contents in pilots increased significantly as compared with that of control group. CONCLUSION: Heat and noise environments might induce increase of lipid peroxidation reaction and decrease of antioxidant ability.

Adult↗

PubMed2000

[The disinfection efficiency comparison of different treatments on dental impression and gypsum casts].

OBJECTIVE: In this study, the disinfecting efficiency of five disinfecting methods to three bacterial: Staphylococcus epidermidis, Streptococcus sanguis and Bacillus subtilis were evaluated. METHODS: Germ free impressions and gypsum casts were divided into three teams contained 16 impressions and 5 gypsum casts for each one. Each team was smeared with each one of the three bacterial solutions. Then four disinfecting methods were administrated on these impressions separately, 2% glutaraldehyde immersion, 2% glutaraldehyde spray, 5% Eric immersion, 5% Eric spray. And ozone treatment was administrated on gypsum casts. Control teams were set up. After the treatment the impressions and gypsum casts were sampled at standard sites. The colonies were counted after culture and were used to deduce the germicidal ratio as the standard of disinfecting efficiency. RESULTS: There was no difference between the efficiencies of five disinfecting methods for Streptococcus sanguis and Staphylococcus epidermidis. But for B. subtilis, the immersion methods have the highest efficiency among the methods and the ozone treatment has the least efficiency. CONCLUSION: 2% glutaraldehyde immersion, spray, 5% Eric immersion, spray are all effective disinfecting methods for impressions and ozone treatment is an effective method in disinfecting the gypsum casts.

Bacillus subtilis↗

PubMed2000

[Laryngostroboscopy in the monitoring of precancerous lesion of vocal cord and in canceration tracing].

OBJECTIVE: To evaluate the value of laryngostroboscopy in the monitoring of precancerous lesion of vocal cord and in the canceration tracing. METHODS: Fifty-two cases of precancerous lesion of vocal cord were examined under Laryngostroboscope. The modifications of mucosal wave and amplitude of vocal cord vibration were observed. All cases were monitored for 1-6 years. RESULTS: The mucosal wave was weak in 45 of 52 cases (86.3%) and the amplitude of vocal cord vibration was weak in 4 of 52 cases (9.6%) with precancerous lesions. However, the mucosal wave disappeared and the amplitude of vocal cord vibration weakened in all 14 cases with early glottic cancer. CONCLUSION: Laryngostroboscopy can be used in diagnosis of glottic precancerous lesion and distinguishing it from the early glottic cancer. It is also an effective means of canceration tracing.

Carcinoma, Squamous Cell↗

PubMed2000

[Expression of substance P receptor mRNA in nasal mucosa of rat in allergic rhinitis model].

OBJECTIVE: To study the expression of substance P receptor messenger RNA (SP-R mRNA) in nasal mucosa in allergic rhinitis (AR) rat model. METHODS: Twenty Wistar rats free of disease were randomly divided into two groups. AR model rats were established through repeated intraperitoneal shot of ovalbumin (OV) and consequently confirmed by local challenge with OV. SP-R mRNA in nasal mucosa, obtained from two groups, were used to do reverse transcriptive polymerase chain reaction (RT-PCR) and Southern blot. beta-actin was used as a standard control through out the whole process. RESULTS: The results showed definitely that there were positive expression of SP-R mRNA in normal nasal mucosa. This expressions increased significantly (P < 0.05) during nasal allergy. CONCLUSION: Increased expression SP-R mRNA in nasal mucosa in AR model might play roles in the development of AR.

Animals↗