Biomedical subjects

H Wang

Publications and source records attributed to H Wang.

At least 937 records · Page 52Linked to original sources

PubMed2000

[Homogeneity study on the Streptococcus suis isolated from human and swine].

OBJECTIVE: To identify S. suis and to evaluate the homogeneity of isolates of S. suis from human and swine. METHODS: Culture, morphology, API biochemical tests and serum coagulate tests were used. All the 7 strains of streptococcus were confirmed to be S. suis serotype 2. Two strains and 1 strain were isolated from blood and cerebrospinal fluid (CSF) of patients, respectively, while the other 4 strains were obtained from the infected swine or their corpses. Seven strains of S. suis serotype 2 and reference strain SS2 were analyzed by randomly amplified polymorphic DNA analysis with six primers and Rep PCR with four primers and thalli fatty acid profile analysis. Cluster and principal compound analysis of results were performed with RAPD, Phylip and Treeview software. RESULTS: By analysis on RAPD patterns, a close relationship among 7 strains of S. suis serotype 2 and reference strain SS2 was discovered. Human-born strains and swine-born strains exhibit similar RAPD patterns. There was a same clonal relationship between strains originated from the blood and CFS of the patients. These results were confirmed by thalli fatty acid profile to have genotypic and phenotypic identity. CONCLUSION: Homogeneity exists among the 7 strains and reference strain SS2.

Animals↗

PubMed2000

[Hostility behavior as risk factor of coronary heart disease].

OBJECTIVE: To explore the relationships between hostility, and the risks of coronary-prone behavior and the clusters of unhealthy behaviors in individuals with different levels of hostility. METHODS: A cross-sectional study was carried out among 1 010 male employees from two factories in Beijing Capital Steel and Iron Company in 1997. Data on major risks of cardiovascular, other social-demographic factors and levels of hostility by Cook-Medley Scales were collected. RESULTS: Body mass index, amounts of cigarette smoking and alcohol drinking were significantly increased (P < 0.01) with a characteristic of reduced social support from one's colleagues, when individual's level of hostility increased. In addition, less years of education, higher prevalence of other chronic diseases (P < 0.05) and clustering of various unhealthy behaviors were found related to the increase of individual's hostility. The odds ratio in the group with highest hostility was 2.37 times higher than in the lowest one, after confounding effects from age, blood pressure, education level, status of chronic disease and social support being adjusted. No significant differences on both systolic and diastolic blood pressures among groups with different levels of hostility were discovered. CONCLUSION: The association between hostility, coronary-prone risk behavior and cluster of unhealthy behaviors suggested that hostility might increase the risk of coronary heart diseases through affecting individual's behavior.

Adolescent↗

PubMed2000

[Studies on algae and microcystin pollution in source water of Yellow River in Zhengzhou city].

OBJECTIVE: To study the law of development of pollution with algae and microcystin (MC) in source water of Yellow River in Zhengzhou city. METHODS: Algae and MC were detected continuously for source water samples collected from B and S Water Works of Zhengzhou in 1998. Microcystin was determined with high-sensitive ELISA. RESULTS: Monthly average density of algae was 1,439 x 10(4)/L in source water of B Water Works of Zhengzhou, with peak algae density of 4,762 x 10(4)/L in August, and that of S Water Works was 1,071 x 10(4)/L. Blue-algae of higher toxicity has become dominant species in source water from S water Works. Detection rate of microcystin was 70.83% in 24 samples collected from the two water works. CONCLUSION: According to Carlson's trophic state index (TSI), as well as other indices, such as total nitrogen, total phosphorus, chemical oxygen demands (COD) and algae density in water, source water in Zhengzhou has presented characteristics of eutrophication.

Bacterial Toxins↗

PubMed2000

[Studies on human streptococcal infectious syndrome caused by infected pigs].

OBJECTIVES: To demonstrate the clinical manifestations of S. suis infectious syndrome; to study the characteristics of causative organism and its source. METHODS: 25 cases of unknown causes of food poisoning were identified in the central area of Jiangsu province, China in July 1998. Biological specimens was collected in some patients, and the causative organism was isolated using a number of different culture medium. Isolated organisms were identified by serum antibody tests, API biochemical tests, drug sensitivity tests and animal model experiments. The human born strains and the pig born strains were compared by RAPD technique. Epidemiological methods were applied to trace the source of causative organisms. RESULTS: Cases were clinically categorized into two types: Streptococcal toxic shock syndrome (STSS) and streptococcal meningitis syndrome (SMS). Three strains of streptococci were isolated respectively from the blood and cerebrospinal fluid of 6 cases. All these 6 strains were confirmed to be S. suis type 2 by culture characteristics, morphology, biochemical characteristics, serum antibody tests and fatty acid profile analysis. Animal model experiment showed that these strains were sensitive to rabbits and pigs, but not to rats. RAPD fingerprint test revealed an identity between human born and pig born strains. CONCLUSIONS: The aetiological agent of these human cases was S. suis type 2. Human cases were contracted by direct contact with the infected pigs or the corpse of infected pigs.

Adult↗

PubMed2000

[Changes of surfactant A and B in alveolar type II cells in hamster with elastase-induced emphysema].

OBJECTIVE: To observe the changes of surfactant A and B (SP-A and SP-B) in alveolar type II cells of lungs in hamsters with elastase-induced emphysema. METHODS: After intratracheal instilling of elastase, hamsters were killed at the 30th, 60th and 90th day of the experiment respectively. Slides of lung tissue were examined under light microscope and measured by calculating the mean linear intercepts. Then the slides were stained under immunohistochemistry procedures and measured by using a morphometric analysis system. Meanwhile, slides were also checked by electron microscopy. RESULTS: In comparison with the normal group, MLI of the elastase group was significantly increased (P < 0.01). Immunohistochemistry showed that the percentage of both SP-A and SP-B positive cells was significantly decreased 30 days after the intratracheal instilling of elastase (from 48.0% +/- 3.0% to 9.5% +/- 4.0% and from 28.0% +/- 4.0% to 13.3% +/- 4.1%, respectively; P < 0.01), however, a time-dependent recovery 90 days after instilling was seen. Electron microscopy showed a significantly decrease of the number of lamellae. CONCLUSION: The decrease of SP-A and SP-B in alveolar type II cells seems to play an important role in the development of emphysema.

Animals↗

PubMed2000

[Zymographic analysis of matrix metalloproteinases in mouse carcinoma cell lines with different lymphatic metastasis potential].

OBJECTIVE: To investigate the correlation between lymphatic metastasis and matrix metalloproteinases (MMPs) activity. METHODS: Zymographic analysis was used to detect the difference of MMPs product and activities between high lymphatic metastatic cell line (HCa-F) and low lymphatic metastatic cell line (HCa-P), that were cultured in the medium including homogenate of lymph node or liver or spleen tissue. RESULTS: HCa-F and HCa-P cells produced small quantities of MMP-9 in 1640 medium. After adding lymph node homogenate to the culture medium, F cells produced a large quantity of MMP-9 as well as active MMP-9 and MMP-2. P cells also produced MMP-9, active MMP-9 and MMP-2, but were much lower than that of F cells. Neither F cells nor P cells produced MMPs in the media with homogenate of liver or spleen added. CONCLUSION: The metastatic potential of F cells is stronger than that of P cells may be due to F cell's ability to secrete MMPs is stronger than P cell's, therefore the production of MMPs of hepatocarcinoma cells is closely correlated to their metastatic potential.

Animals↗

PubMed2000

[Expression of proliferation and apoptosis related genes in colorectal adenoma with malignant transformation].

OBJECTIVE: The effect of proliferation and apoptosis related genes of colorectal adenoma with malignant transformation and its clinicopathologic significance was studied. METHODS: p53, bcl-2, Fas, bax expression were detected immunohistochemically in 61 cases of colorectal adenoma with either mild or severe dysplasia and carcinoma. The rate of proliferation was evaluated with Ki-67 and apoptosis with TUNEL. RESULTS: The positive rates for p53 and bcl-2 protein in carcinomatous area, adenoma with severe and mild dysplasia were 67.2%, 57.4%, 19.7% and 77.1%, 80.3%, 49.2% respectively. The mean Ki-67 index and PCD index were 38.4%, 36.5%, 16.1% and 2.2%, 1.9%, 0.5% respectively. The difference of the expression of p53 protein, bcl-2 protein and Ki-67 index, PCD index in carcinomatous region and adenoma with severe dysplasia compared with mild dysplasia was statistically significant (P < 0.05). CONCLUSION: It is apparent that both apoptosis inhibition and abnormal proliferation play an important role in tumor formation. Adenoma with severe dysplasia is a lesion very close to carcinoma in nature, which possesses active tendency to become fully malignant. Detection of these proteins is important in the early diagnosis of malignant transformation of an adenoma.

Adenoma↗

PubMed2000

[Study on the pharmacokinetics of Imipenem cilastatin in burn patients during the acute phase].

OBJECTIVE: To investigate the pharmacokinetic characteristics of Imipenem/cilastatin in burn patients during the acute phase. METHODS: Imipenem concentrations in the plasma, blister and, interstitial fluids and urine of 6 burn patients (P group) were determined during the acute phase by high performance liquid chromatography after the first initial dose. Pharmacokinetic parameters were thus produced and statistically analyzed by program package STAT 5. Ten healthy volunteers served as control group (C group). RESULTS: Compared to those in control group, pharmacokinetic parameters of Imipenem exhibited evident difference, such as prolonged half-life [(1.56 plus minus 0.55) h vs (1.06 plus minus 0.24) h] and enlarged distributing volume (16.16 plus minus 4.26) vs (13.96 plus minus 7.10). Imipenem could be detected in the blister and interstitial fluids of burn patients 1 hr after the initial dose. Renal clearance of Imipenem was positively correlated to creatinine clearance (r = 0.5834). CONCLUSION: The intervals between doses should better be prolonged when loaded-dosage of Imipenem was administered in burn patients during the acute phase. Imipenem could penetrate II and III degree burn wound when given in the acute phase. Attention should be paid to renal function when Imipenem was given.

Adult↗

PubMed2000

[Effects of holothuria glycosaminoglycan on the expression of tissue factor and thrombomodulin in stimulated endothelial cells].

OBJECTIVE: To study the mechanism of antithrombotic effects of holothuria glycosaminoglycan (GAG). METHODS: Endothelial cells from human umbilical vein which were pre-induced with 1 mg/L lipopolysaccharide, were treated by GAG (1 mg/L, 5 mg/L, and 10 mg/L, respectively) and 5 mg/L heparin as a control for 6 hours. Procoagulant activity (PCA), the expressions of tissue factor (TF) antigen and thrombomodulin (TM) antigen and their mRNA transcriptions were investigated. RESULTS: GAG could down-regulate the expression of TF antigen and mRNA, up-regulate the expression of TM antigen and mRNA, down-regulate the PCA of stimulated endothelial cells. CONCLUSION: Down-regulating TF expression and up-regulating TM expression of stimulated endothelial cells may be one of the mechanisms of GAG antithrombosis.

Animals↗

PubMed2000

[Mechanism of tissue factor expression on NB4 cells down-regulated by all-trans retinoic acid and arsenic trioxide].

OBJECTIVE: To investigate molecular mechanism of tissue factor (TF) expression on acute promyelocytic leukemia cell line NB4 cells down-regulated by all-trans retinoic acid (ATRA) and arsenic trioxide (As(2)O(3)). METHODS: Cyclohexamide (CHX) inhibition test for de novo protein synthesis and actinomycin D (Act D) inhibition test for RNA synthesis were used to check the effect of ATRA on the TF expression. TF antigen of U937 cells transfected with pMSCV-PML-RARalpha treated with or without ATRA and As(2)O(3) was detected. RESULTS: CHX treatment completely suppressed the down-regulation effect of ATRA on the TF mRNA expression, Act D inhibition test showed that half-life of TF mRNA in treated NB4 cells was shortened to about 30 min from that of around 60 min in untreated NB4 cells. The TF antigen contents in U937 cells transfected with pMSCV-PML-RARalpha were significantly higher than that in transfected U937 cells with retrovirus vector. Both ATRA and As(2)O(3) could down-regulate the TF antigen level in U937 cells transfected with or without PML-RARalpha. CONCLUSION: The modulation of the TF mRNA expression in NB4 cells by ATRA might be indirect. TF mRNA destabilization was involved in the TF regulation process mediated by ATRA. Elevated TF antigen level in U937 cells transfected with pMSCV-PML-RARalpha may be related to the fusion protein PML-RARalpha. The down-regulation effect of ATRA and As(2)O(3) on the TF expression of U937 cells might not involve the fusion protein.

Antineoplastic Agents↗

PubMed2000

[A preliminary study on placenta hematopoiesis].

OBJECTIVE: To study the role of placenta on fetal hematopoiesis during embryo ontogeny, so as to find a new source of hematopoietic stem/progenitor cells (HSC/HPC) for clinical transplantation. METHODS: Cord blood was collected separately from cord vein and artery. CD(34)(+) cells were detected by FACS, CFU-GM semisolid agar culture, and hematopoietic growth factors (HGFs) by ELISA. The results of HE stain and CD(34) McAb immunohistochemistry stain of placenta chorionic villi were investigated. RESULTS: The CFU-GM yields and the percentage of CD(34)(+) and CD(34)(+)/CD(38)(minus sign) cells in cord vein were higher than that in artery. The cord vein contained larger amount of hematopoietic stimulating factors and similar level of hematopoietic inhibitory factors as compared with that in artery. Blood island, reticular cells and scattered CD(34)(+) cells were found in the mesenchyme of placenta chorionic villi. CONCLUSION: The placenta might be an another hematopoietic organ in ontogeny. It could be applied to clinical hematopoietic cell transplantation.

Antigens, CD34↗

PubMed2000

[Retroviral-mediated high efficient in vitro expression of human coagulation factor VIII].

OBJECTIVE: To develop a retroviral-mediated high efficient expression system of human coagulation factor VIII. METHODS: The retroviral vector LNC-VIIIBD was generated by cloning a B-domain-deleted FVIII cDNA (760aa - 1639aa) into retroviral vector pLNCX. Several cell lines including NIH3T3, CHO, COS-7 and human hepatic cell line L-02 were infected with viral supernatant from the highest productive PA317 clones. The antigen and procoagulant activity of human FVIII in the cell culture medium were measured by ELISA assay and one-stage method, respectively. RT-PCR was performed for the detection of F VIII BD mRNA. RESULTS: Human FVIII was expressed in all four target cells. The highest expression was observed in NIH3T3, the procoagulant activity of secreted FVIII was up to 1.6 U, and the FVIII antigen was 500 ng by 10(6) cells/ml in 24 hours, respectively. CONCLUSION: The constructed retroviral vector was able to generate high level expression of human FVIII in some cell lines, and it might have potential utility in the gene therapy for Hemophilia A.

3T3 Cells↗

PubMed2000

[Preliminary study on the effects of coagulation factor XII on fibrinolysis].

OBJECTIVE: To study the effects of FXII on fibrinolysis in patients with cerebral thrombosis. METHODS: Plasma level of FXII:C, FXII:Ag, FXIIa and beta FXIIa and fibrinolysis activities were examined by ELISA. Screening of FXII gene mutation by MOEA. RESULTS: FXII:C in 22 of 107 patients with cerebral thrombosis decreased, which was similar to the feature of FXII cross-reacting material positive (FXII CRM(+)). There were significant increase in plasma levels of PLG:A and alpha(2)AP:A and decrease in D-dimer, moreover, plasma levels of FXIIa and betaFXIIa were lower in patients than in controls. FXII gene mutation was not found in 22 of 107 patients. CONCLUSION: Decrease of FXII:C may play an important role in cerebral thrombosis by reducing activation of plasminogen. The gene mutation of FXII CRM(+)-like abnormal FXII was different from the known FXII gene mutation. Mutations in the regions of FXII Arg (334) and Arg (353) may be more important for the reducing of FXIIa, beta FXIIa levels and fibrinolysis activities. FXII assay should be included in thrombotic disorder screening.

Adult↗

PubMed2000

[Hemostatic variations associated with acute leukemia: clinical and prognostic significance].

OBJECTIVE: To study the hemostatic abnormalities and their association with bleeding manifestation and prognosis in acute leukemia (AL) patients. METHODS: A series of hemostatic parameters were determined in 93 cases of AL using ELISA or chromogenic assay. RESULTS: At diagnosis, plasma levels of P-selectin, soluble fibrinomonomer complex (SFMC), thrombomodulin (TM), tissue plasminogen activator, D-dimer (D-D) were significantly elevated, but protein C antigen (PC:Ag), plasminogen (PLG), alpha(2)-antiplasmin (alpha(2)-PI) and plasminogen activator inhibitor (PAI) were decreased, and fibrinogen (Fg), PC activity (PC:A) and protein S (PS) were in normal range. All the above abnormalities returned to normal after complete remission (CR) except for PC:A and PC:Ag. Platelet counts, Fg, SFMC, PLG, alpha(2)-PI and D-D were significantly associated with hemorrhagic manifestations. TM, PS and PAI were related to prognosis. CONCLUSION: There existed the consumption of platelets as well as the activation of coagulant, anticoagulant and fibrinolytic systems in AL, which was greatly improved after CR.

Acute Disease↗

PubMed2000

[Umbilical cord blood stem cells transplantation from an unrelated donor into an adult with severe aplastic anemia].

OBJECTIVE: To evaluate the availability of the treatment of adult severe aplastic anemia with unrelated allo-cord blood stem cell transplantation (CBSCT). METHODS: HLA-matched unrelated cord blood transplantation has been successfully performed for an adult severe aplastic anemia patient. A unit of cord blood provided by Guangzhou Cord Blood Bank containing 1.89 x 10(7)/kg mononucleated cells, 1.8 x 10(4)/kg CFU-GM and of CD(34) positive cells was 0.009. The patient was conditioned with CTX (60 mg/kg) and anti-lymphocyte globulin (ALG, 120 mg/kg). GVHD prophylaxis consisted of both MTX and CsA. The CsA had been given for 8 months. RESULTS: The lowest ANC was 0.6 x 10(9)/L post-transplantation. The patient achieved an ANC of greater than 0.5 x 10(9)/L at 10 days, and the platelet of greater than 50.0 x 10(9)/L at day 20 after transplantation. He developed Grade 1 GVHD in the tenth month after grafting. Microsatellite DNA fingerprinting indicated a stable donor-recipient mixed chimerism, whilst the circulating red cells remained host origin. CONCLUSION: It is the first report in China on successful treatment of adult severe aplastic anemia by unrelated allo-CBSCT.

Adult↗

PubMed2000

[Ethological examination of Alzheimer's disease model rats treated with bushen yizhi decoction].

OBJECTIVE: To explore the ethological improving effect of Bushen Yizhi Decoction (BSYZD) in treating model rat of Alzheimer's disease (AD). METHODS: Ethologic examination was carried out with Morris water maze on young, aged, AD model, Huperzine A treated and BSYZD treated groups of rats. RESULTS: In the BSYZD treated group, the escape latency (EL) curve placed between that of the young, aged and AD model, Huperzine A treated group; the percentage of middle circle swim path, the 40 cm circle swimming time, and the platform-crossing times were not different from those in the normal aged group, but were different significantly as compared with the AD model group, P < 0.05. CONCLUSION: BSYZD could ameliorate the behavior deficits of AD model.

Alzheimer Disease↗

PubMed2000

[Modulatory effects of 17beta-estradiol on the electrical activity of subfornical organ neurons].

The effects of 17beta-estradiol (E(2) ) on electrical activity of neurons in subfornical organ (SFO) slices were examined using extracelluar recording technique. The results are as follows. (1) In 15 SFO units, a low dose of E(2) (0.1 nmol/L) applied into superfusate induced an increase in discharge rate from 3.21+/-0.37 to 6.79+/-0.71 Hz (P<0.001), whereas a high dose of E(2) (100 nmol/L ) caused a decrease in discharge rate from 3.44+/-0.40 to 1.44+/-0.36 Hz (P<0.01); (2) glutamate NMDA receptor antagonist MK-801 (50 pmol/L) blocked the excitatory effects induced by low dose of 17beta-estradiol in 7 units; (3) L-arginine (L-arg, 1 mmol/L), a physiological precursor of NO, abolished the excitatory effects induced by low dose of 17beta-estradiol in 7 units; (4) application of N-omega-nitro-L-arginine methyl ester (L-NAME, 10 mmol/L), an inhibitor of NOS, blocked the inhibitory effects induced by high dose of 17beta-estradiol in 6 units. The above results suggest that the estrogen exerts dual action on SFO neuron. E(2) at low dosage increases the discharge rate of SFO neuron, an effect which may be related to the activation of NMDA receptors, whereas E(2) at high dosage decreases the discharge rate, an effect which may be attributed to the activation of NOS with resultant production of NO.

Animals↗

PubMed2000

[Adenosine inhibits spontaneous and glutamate induced discharges of hippocampal CA1 neurons].

Effects of adenosine (Ado) on spontaneous and glutamate induced discharges of neurons in CA1 area of hippocampal slices were examined using extracelluar recording technique. The results are as follows. (1) In response to the application of Ado (0.01 0.1 micromol/L, n=20) into the superfusate, spontaneous discharge rates (SDR) of 20 neurons decreased significantly in a dose dependent manner. (2) Both Ado non selective receptor antagonist 8 phenyltheophylline (8-PT, 0.5 mmol/L) and Ado selective A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 50 nmol/L), completely blocked the inhibitory effects of Ado in 22 CA1 units. (3) In 10 units, ATP sensitive K(+) channel blocker glibenclamide (Gli, 15 mmol/L) also abolished the effect of Ado. (4) Application of glutamate (Glu, 0.2 mmol/L) into the superfusate for 2 min led to a marked increase in the discharge rate of 15 neurons in an epileptiform pattern; the epileptiform discharges induced by glutamate (Glu, 0.2 mmol/L) in 15 neurons were suppressed significantly by application of Ado (10 micromol/L) into the superfusate. (5) 8-PT (2 mmol/L), DPCPX (200 nmol/L) and Gli (7 mmol/L) were all capable of abolishing the inhibiting effect of Ado on the action of glutamate. Taken together, it is suggested that Ado can bind with adenosine A1-receptors on CA1 neurons, resulting in an activation of K(ATP) channels and inhibition of neuronal activity. The inhibitory effect of Ado on glutamate induced epileptiform activities in rat hippocampal neurons is also mediated by adenosine A1-receptor with involvement of ATP-sensitive potassium channels.

Adenosine↗