Biomedical subjects
J Wu
Publications and source records attributed to J Wu.
Cloning and sequencing of the fragment of angiostatin K (1-3) gene.
OBJECTIVE: To secure anti-endotheliocyte hyperplasia functional fragment of human angiostatin K (1-3) gene. METHODS: As the template of leukocytotic cDNA, functional fragment of human angiostatin K (1-3) cDNA was amplified by PCR, cloned into the vector pGEM-3Zf, and sequenced according to Dye primer sequencing kit. RESULTS: The functional fragment of angiostatin K (1-3) cDNA (859 bp) was obtained by PCR and determined by sequencing. CONCLUSION: The angiostatin K (1-3) gene has been cloned. The gene is of great significance in tumor-antiangiogenesis therapy.
Cutaneous and subcutaneous mast cell and eosinophil responses after challenge in mice vaccinated with living infective third-stage hookworm larvae.
OBJECTIVE: To examine the quantitative and qualitative alterations in mast cells and eosinophils distributed in the cutaneous and subcutaneous tissues of hookworm-infected, uninfected and vaccinated mice. METHODS: Outbred male Kunming strain mice, weighing 18-22 g, were vaccinated thrice by subcutaneous inoculation with 500 living third-stage infective larvae (L3) of Ancylostoma caninum (A. caninum) every 2 weeks, and then challenged subcutaneously with 500 L3 one week after the final immunization. Uninfected mice and non-immunized mice but infected with L3 served as controls. The abdominal skin at the site of percutaneous entry was excised from challenged mice at intervals between 6 hours and 7 days after challenge, fixed, and then examined by light microscopy after staining with either toluidine blue or hematoxylin and eosin. RESULTS: The total number of mast cells appearing in cutaneous, and subcutaneous tissues, and underlying abdominal musculature of immunized mice increased significantly compared with non-immunized mice. Mast cells from hookworm-infected mice showed evidence of membrane rupture and degranulation in contrast to the intact appearance of mast cells from uninfected mice. The degree of mast cell degranulation was greater in vaccinated and challenged mice when compared with non-immunized and infected mice. Similarly, eosinophilic infiltration was greatly enhanced after L3 infection. Tissues from vaccinated mice had a greater number of eosinophils than non-immunized mice after infection. CONCLUSIONS: Mast cell alterations appearing earlier than tissue eosinophilic infiltration is major inflammatory response to Ancylostoma caninum (A. caninum) L3 infection in mice. These processes are more obvious in L3-vaccinated mice.
[Clinical study of metastasis of thoracic lymph node in resectable lung cancer].
OBJECTIVE: To study the metastatic pattern of thoracic lymph node in resectable lung cancer. METHODS: From January 1992 to July 1998, the lymph nodes in hilar(N1) and mediastinal(N2) were resected based on their distribution in 160 patiens with resectable lung cancer and were examined by pathology. Number, size and colour of lymph nodes in each regions were recorded. Each lymph node was examined by routine pathology and immunohistochemistry. Quantity of metastatic lymph node was reported according to their regions. RESULTS: 99 cases(61.9%) had thoracic lymph nodes metastasis and 73 cases (45.6%) had mediastinal lymph nodes metastasis. Of those, only N1 metastasis was 16.3%, from N1 to N2 metastasis was 32.5%, only N2 metastasis was 13.1%. The metastatic frequencies in 11, 10, 7, 5 and 4 regions around the hilar or root of lung were 30.0%, 27.5%, 16.9%, 28.8% and 20.0%, respectively. Those were higher than 9, 6, 3, 2 and 1 regions far from the root of lung. The metastatic rate of lymph node in 2.0 cm or greater, 1.0 cm or greater and less than 1.0 cm was 60.7%, 15.5% and 4.3%, respectively (P < 0.001). The smallest metastatic lymph node was only 0.2 cm x 0.2 cm. Statistical analysis revealed that metastatic rate of thoracic lymph nodes was not relevant to different area, size and course of tumors. CONCLUSIONS: The lymph nodes metastases of most cases were spreading from the near to the distant, from lower to upper, through the hilar to the mediastinal. Lymph nodes metastases occurred easier in SCLC than in NSCLC (P < 0.05). It must be depended on pathologic examination to confirm whether or not the tumor has metastasis to lymph node.
[Prognostic significance of cyclin-dependent kinase inhibitor p27kip1 expression in human breast cancer].
OBJECTIVE: To study the expression of p27kip1 in breast cancer in relation to biological behavior and prognosis. METHODS: p27kip1 expression at protein level was determined by immunohistochemistry technique in 181 patients with breast cancer. In addition, p27WAF1/CIP1, p53 and mdm2 were examined in 106 cases of this series. Data about apoptotic index, bcl-2 and bax protein expression were available in the other 91 patients. RESULTS: Of the 181 patients, p27kip1 expression was low in 121 (66.9%) and high in 60 (33.1%), respectively. p27kip1 expression level was correlated with histological grade, tumor size, axillary lymph node status, post-operative recurrence, invasion and metastasis. It was also correlated with bcl-2, bax, p53, p21WAF1/CIP1, and mdm2 expression levels. Univariate analysis demonstrated better disease-free survival in patients with higher p27kip1 expression than in those with lower expression. However, by Cox multivariate analysis, p27kip1 expression level was not found to be of independent prognostic significance. CONCLUSION: As an inhibitor of cyclin-dependent kinase, p27kip1 favors prognosis of human breast cancer not only by arresting cell cycle in G1 phase but also inducing cancer cell apoptosis.
[Preparation of monoclonal antibodies to human vascular endothelial growth factor(VEGF121) and identification of its expression on gastric carcinoma cell line MGC803].
OBJECTIVE: To further elucidate the source of VEGF in solid tumors. METHODS: Traditional hybridoma technology was used to prepare VEGF monoclonal antibodies (McAb); it's activity was measured by 3H-TdR incorporation on human umbilical vein endothelial cells (HUVEC). VEGF gene was amplified by PCR with cDNA as template from MGC803 cell lines. The PCR products were cloned into fusion protein prokaryotic expression vector PGEX2T which expressed in E. coli XL-1 blue. Western blot analysis was used to identify expression of VEGF. RESULTS: The McAbs could specifically bind to VEGF in ELISA. One of the McAbs(5C5) could neutralize the mitogenic activity of VEGF121 on HUVEC in a dose-dependent manner. The VEGF gene fragment obtained from RT-PCR cloned to PGEX2T vector expressed a protein product which reacted specifically with McAb 5C5. CONCLUSION: Gastric carcinoma is shown to express VEGF. It may be a major source of VEGF in human solid tumor. Monoclonal antibody against VEGF may be of value in the treatment of cancer.
[Cloning and monoclonal antibody preparation of VEGF receptor KDR extracellular V-VII domain and KDR expression in carcinomas of different origins].
OBJECTIVE: To examine the expression of VEGF receptor KDR in carcinomas of different origins and provide possibility of exploring its relation to tumor growth and metastasis. METHODS: VEGF receptor KDR cDNA (V-VII) fragment was cloned from human umbilical vein with RT-PCR and expressed in E. coli Jm109. The purified GST-KDR fusion protein was used to immunize Balb/c mice and monoclonal antibody against KDR was prepared. With this monoclonal antibody, tumor tissue and related normal tissue of different origins were examined immunohistochemically for KDR expression. RESULTS: The frequency and intensity of KDR expression in different tumor tissues were obviously different. Transitional-cell cancer of urinary bladder was 100% KDR positive and with highest intensity, while KDR expression in breast and intestinal adenocarcinoma was weaker and that in squamous-cell carcinoma of the lung was weakest. Moreover, KDR was also weakly expressed in other cells, such as smooth muscle cells and interstitial cells. CONCLUSION: VEGF receptor is expressed not only in the endothelial cells of tumor vasculature, but also in tumor cells. Tumor cell expression of KDR varies in intensity with tumors of different origins. The possible significance of VEGF receptor expression with regard to tumor cell proliferation and metastasis is discussed.
[Study on essence of syndrome of traditional Chinese medicine in liver cirrhotic patients].
OBJECTIVE: To explore the essence of Syndrome of traditional Chinese medicine (TCM) in cirrhostic patients. METHODS: Eighty patients of post-hepatitis-B cirrhosis were classified, according to Syndrome Differentiation of TCM, into three types: the Liver-Qi Stagnancy and Spleen-Deficiency type (A), the Qi-Stagnancy and blood stasis type (B) and the Heat Stagnancy and blood stasis type (C), serum hyaluronic acid (HA), adenosine deaminase (ADA), glutathione-s-epoxide transferase (GST), N-acetyl-beta-D-glucosaminidase (NAG), hydroxyproline (HYP) and procollagen type III (PC III) of 52 patients were determined before and after treatment based on Syndrome Differentiation. RESULTS: Serum HA, ADA, GST and PC III of patients were significantly higher than those of the healthy control (P < 0.01), and the change of these parameters were closely associated with types of Syndrome, which were, in turn, C > B > A > control, the difference between groups was significant (P < 0.05, P < 0.01). After treatment, the liver function and above-mentioned serologic parameters were significantly improved (P < 0.05, P < 0.01). CONCLUSIONS: Syndrome of cirrhosis patients has its inherent essential content. Serum HA, ADA, GST and PC III could serve as objective indexes for establishing Syndrome Differentiation and guiding treatment. TCM treatment of cirrhosis based on Syndrome Differentiation has good effect with beneficial anti-fibrotic action.
Treatment of Helicobacter pylori infection.
The availability of clinic-based diagnostic tests means that screening for and the eradication of Helicobacter pylori can be done by primary care physicians. However, confusion still exists regarding indication and treatment regimens. It is universally accepted that patients with Helicobacter pylori infection and peptic ulcer disease require eradication therapy. But the benefits of Helicobacter pylori eradication in gastro-oesophageal reflux disease, non-steroidal anti-inflammatory drug-related peptic ulceration, and non-ulcer dyspepsia remain unclear. There is no evidence that the elimination of Helicobacter pylori is beneficial for asymptomatic patients or in preventing gastric cancer. One-week triple therapy with a proton pump inhibitor or ranitidine bismuth citrate in combination with clarithromycin/metronidazole and amoxycillin is the recommended first-line treatment for Helicobacter pylori infection. Problems with patient compliance and the development of antibiotic resistance are the two most important factors to consider when choosing the treatment regimen. The optimal retreatment therapy for treatment failure is still unknown, and quadruple therapy is best reserved for these cases.
[The effects of moderate acute normovolemic hemodilution on intestinal oxygen supply and consumption in anesthetized cats].
OBJECTIVE: To study the effects of moderate acute normovolemic hemodilution on the intestinal blood perfusion and oxygen supply in cats. METHODS: 15 domestic male cats were hemodiluted with Haemaccel. HR, MAP, lactate concentration in superior mesenteric vein (LAC), superior mesenteric artery blood flow (SMABF), superior mesenteric artery and venous blood gas analysis were recorded and the intestinal oxygen delivery (DO(2)), oxygen consumption (VO(2)) and oxygen extraction (EO(2)) were calculated before and after hemodilution. RESULTS: SMABF increased obviously (P < 0.05), intestinal DO(2) and EO(2) did not change (P > 0.05) but VO(2) increased (P < 0.05), and LAC in superior mesenteric vein did not increase. CONCLUSIONS: Moderate acute normovolemic hemodilution with Haemaccel do not alter intestinal oxygen delivery by increasing the superior mesenteric blood flow. It means that intestinal mucosa ischemia does not happen during moderate acute normovolemic hemodilution.
[Expression of nuclear transcription factor NF-kappaB in human corneal fibroblasts].
OBJECTIVE: To explore the constitutive expression and activation of nuclear transcription factor NF-kappaB in corneal fibroblasts. METHODS: 2 or 3 passage corneal fibroblasts cultured in vitro were divided into two groups after synchronization. One group was cultured in DEME free of serum; the other in DEME with 10 microg/ml lipopolysaccharides for 6 hours. NF-kappaB was studied by flow cytometry (FCM) technique using immunofluorescent staining, and by gel shift assay (EMSA) using gamma-(32)P labeled NF-kappaB oligonucleotide probe. RESULTS: According to FCM results, there were constitutively 9.4% NF-kappaB positive corneal fibroblasts, and 2.2 folds more (30.0%) after stimulated with lipopolysaccharides. Using EMSA method, we demonstrated the existence of NF-kappaB with DNA binding activity in the stimulated nuclei. CONCLUSION: There is nuclear transcription factor NF-kappaB in human corneal fibroblasts. When activated, cells express more transcription factor which can enter nuclei, bind itself to the related DNAs and play a regulatory role of gene transcription.
[Effects of epidermal growth factor, basic fibroblast growth factor and 5-fluorouracil on human retinal pigment epithelial wound closure in vitro].
OBJECTIVE: To study the effects of epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and 5-fluorouracil (5-Fu) on the cell migration and proliferation. METHODS: Phase-contrast microscopy, cell proliferation assay and wound -closure were used to study the process of cell proliferation and wound healing in a model of human retinal pigment epithelial (RPE) cell damage. RESULTS: It was found that EGF mainly stimulated proliferation and the migration of individual RPE cells from the wound edge, and induced cellular elongation, while bFGF mainly promoted proliferation and spread of the confluent monolayer into the wound defect, and induced enlargement and flattening of cells. But the effects of EGF, bFGF on wound closure were not very significant; 5-Fu inhibited the spread and proliferation of RPE cells, but had no effects on cell migration. CONCLUSIONS: EGF and bFGF have no significant effects on wound-healing, perhaps their effects on cell morphology are very important in cell transformation in proliferative vitreoretinopathy (PVR), and 5-Fu can only be a subsidiary drug to prevent PVR.
[The relationship between anticardiolipin antibodies and fetal intrauterine growth retardation].
To investigate the relationship between anticardiolipin antibodies(ACA) and fetal intrauterine growth retardation(IUGR), serum ACA was determined in 60 pregnant women by enzyme linked immunosorbent assay(ELISA). Binding index(BI) of ACA-IgM or ACA-IgG in cases with IUGR(n = 30) was significantly higher than that in normal pregnant women(n = 30) (P < 0.05). There was no obvious relationship between the weight of neonate and BI of ACA-IgM(r = 0.1904), ACA-IgA(r = 0.1829) or ACA-IgG(r = 0.2013) in IUGR group. Increased ACA-IgM had a negative association with C3 (r = -0.4108, P < 0.05) and C4(r = -0.4092, P < 0.05), respectively. After routine therapy for IUGR during 27-35 weeks' gestation, the weights of neonates were 2436.87 +/- 437.29 gram in ACA-IgG positive group(n = 15) and 2905.33 +/- 195.95 gram in ACA-IgG negative group(n = 15). There was a statistical significance between these two groups(P < 0.01). It is concluded that ACA may play an important role in the pathogenesis of IUGR. The determination of ACA is also useful for early diagnosis and treatment of IUGR.
[Relationship between nitric oxide and oxygen free radicals in different duration of diabetes in rat kidney].
To study the relationship between nitric oxide(NO) and oxygen free radicals in rat kidney of diabetes mellitus(DM), the authors examined the changes of renal tissue NO level and nitric oxide synthase(NOS) activity, lipid peroxidation(LPO) level and superoxide dismutase(SOD), peroxidase(POD) and catalase (CAT) activities in streptozotocin(STZ)-induced diabetic rats and normal controls(NC) at the 2nd, 8th- and 16th-week. The results showed that renal-tissue NO level and NOS activity were increased at the 2nd week, but decreased at the 8th- and 16th-week; LPO levels were significantly elevated in all DM groups than those in NC groups. SOD, POD and CAT activities decreased significantly in the 8th and 16th week DM groups compared with those in NC groups. The results suggest that NO level in kidney of STZ-induced diabetic rats dynamically change with the disease course of development. This change may be related with the change of anti-oxidation in kidney which high glucose induces.
[Intracerebral distribution of albumin after closed brain traumas].
Twenty cases of closed brain traumas were investigated immunohistochemically to detect intracerebral distribution of albumin. The brain contusions' areas were heavily stained in all cases, even in those of only 15 minutes' survival. Some neurons, nerve fibers, astrocytes and gitter cells of the softening area both nearby the contusion areas and far from the contusion areas, including thalamus, midbrain, pons and medulla, were also heavily stained in all cases. The marked immunoreactivity to albumin also took place in extravascular spaces, endothelial cells and membrane of red blood cells. The results suggested that immunohistochemical staining of albumin should be a sign of early brain trauma, inclusive of brainstem trauma. It is especially useful in the identification of brain traumas without bleeding.
[Cerebral protective effects of some compounds isolated from traditional Chinese herbs].
OBJECTIVE: To study the cerebral protective effects of some compounds isolated from traditional Chinese herbs. METHOD: Laser microcirculation dynamic analyzer and cultured rat cortical neurons were used. RESULT: Pueraria lobata flavonoids(LPF), Panax notoginseng saponins(PNS), oxymatrine, anisodamine and berberine could dilate microvessels and increase the cerebral blood flow of anesthetized mice's meninges. LPF, PNS, oxymatrine, and anisodamine also accelerated the flow of blood. Oxymatrine, like anisodamine, increased quantities of erythrocytes in high frequency movements. PNS could protect cultured rat cortical neurons from glutamate neurotoxicity. CONCLUSION: LPF, PNS, oxymatrine, anisodamine and berberine have certain protective effects on brain, but differ in mechanisms of action.
[Sub-cloning and preliminary sequence analysis of the gene encoding of a cefoperazone hydrolyzing beta-lactamase isolated from Escherichia coli].
Escherichia coli HX88108, which is resistant to cefoperazone(CPZ), was isolated from a severely infected patient. We studied genetical basis of beta-lactamase produced in E. coli HX88108 by pFL25, one of the recombinant plasmid of pFC. Largescale pFL25 plasmid was extracted, purified, and cleaved with restriction endonuclease EcoR I, Sal I, Pvu I, then subcloned into vector pUC19 as 1.9 kb, 0.9 kb, 0.65 kb fragments respectively. Recomminant plasmids were selected by alpha-complementation and determined by restriction endonuclease analysis. DNA sequencing was performed by the dideoxy polymerase chain termination method. Partial nucleotide sequence(1-78 nucleotide position) of the gene was found to be highly homologous (97%) with the gene coding for TEM-52 extended spectrum beta-lactamase of K. pneumonise, suggesting that the beta-lactamase coded by the cefoperazone resistant gene might be derived from TEM-type beta-lactamase.
[Genetic polymorphism at D3S1545 locus in Chengdu Han and Dali Bai populations in China].
The objective of this study was to understand the distribution of the genetic polymorphisms of STR locus D3S1545 in Chinese populations. EDTA-blood specimens were collected from 148 healthy unrelated Han individuals in Chengdu and 96 healthy unrelated Bai individuals in Dali. The DNA samples were extracted using Chelex method, and then they were amplified by PCR technique. PAGE horizontal electrophoresis was used for typing the PCR product. The results there were nine alleles at D3S1545 locus in Chengdu Han population and six alleles at D3S1545 locus in Dali Bai population. The allele frequencies of Chengdu Han population were D3S1545 * 8:0.0642; D3S1545 * 9:0.0034; D3S1545 * 10:0.0068; D3S1545 * 11:0.0203; D3S1545 * 12:0.1824; D3S1545 * 13:0.3075; D3S1545 * 14:0.3243; D3S1545 * 15:0.0844; D3S1545 * 16:0.0068; and 23 genotypes were observed. The allele frequencies of Dali Bai population were D3S1545 * 8:0.00781; D3S1545 * 11:0.0261; D3S1545 * 12:0.1719; D3S1545 * 13:0.3906; D3S1545 * 14:0.2448; D3S1545 * 15:0.0885; and 16 genotypes were observed. The results of test for Hardy-Weinberg equilibrium showed that the genotype distributions observed at the populations were correspondent with the expected. These findings suggest that the allele frequencies at D3S1545 locus in Chengdu Hans have not remarkable different from those in the Bai population of Dali. D3S1545 may be a useful marker for paternity test and personal identification of biological stain.