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Biomedical subjects

X L Wang

Publications and source records attributed to X L Wang.

At least 55 records · Page 3Linked to original sources
PubMed2001

Percutaneous transsplenic embolization of esophageal and gastrio-fundal varices in 18 patients.

AIM: Clinical application and potential complication of percutaneous transsplenic varices embolization (PTSVE) of esophageal or gastrio-fundal varices in patients with hepatocellular carcinoma (HCC) complicated with portal vein cancerous thrombosis (PVCT). METHODS: 18 patients with HCC complicated with PVCT and esophageal or gastrio-fundal varices who underwent PTSVE were collected. The rate of success, complication, mortality of the procedure and postoperative complication were recorded and analyzed. RESULTS: PTSVE were successfully performed in 16 of 18 cases, and the rate of success was 89%. After therapy erythrocyte counts decreased in all of the natunts. 5 of patients needed blood transfusion, 2 patients required surgical intervention because of and 11 patients with ascites were alleviated by diuresis. Among these 18 patients, the procedure-related mortality was 11% (2/18), one died of acute hepatic failure on the forth day after procedure, another died of acute renal failure on the fifth day. The patients were follow up for 1-12 mon exceptone. 13 of them died of their tumors but none of them experienced variceal bleeding. CONCLUSION: PTSVE is a relatively safe and effective method to treat esophageal or gastrio-fundal varices in HCC patients with PVCT when percutaneous transhepatic varices embolization (PTHVE) of varices is impossible.

Adult↗
PubMed2001

TGF-beta increases retinal endothelial cell permeability by increasing MMP-9: possible role of glial cells in endothelial barrier function.

PURPOSE: To determine transforming growth factor (TGF) beta effects on matrix metalloproteinases (MMPs) as a potential cause of the blood-retinal barrier breakdown at the onset of angiogenesis. Previously, glial cells were shown to play a role in the angiogenesis process and to express the angiogenic regulating factor TGF-beta, which becomes active under hypoxia conditions. Here, the authors demonstrate that retinal endothelial cells express MMP-9 when treated with TGF-beta or cocultured with glial cells and that both TGF-beta and MMP-9 increase endothelial cell permeability. METHODS: Primary cultures of bovine retinal endothelial (BRE) cells grown on porous membranes were treated with TGF-beta or purified MMP-9, and permeability changes were assayed. The amount and distribution of the tight junction protein occludin also was analyzed by immunocytochemistry and Western blotting. Cell extracts or conditioned media from TGF-beta-treated BRE cells and from glial cell-BRE cocultures were analyzed for MMP-9 content by substrate gel electrophoresis (zymography) or Western blotting. RESULTS: Both TGF-beta and MMP-9 increased the permeability of BRE monolayers and reduced the levels of the junction protein occludin. The effect of MMP-9 on permeability was rapid, but the TGF-beta-induced permeability required longer incubation and was blocked by anti-TGF-beta and anti-MMP-9 antibodies as well as by TGF-beta latency-associated peptide. Zymography showed that MMP-9 activity, which was very low or absent in untreated BRE cultures, was dramatically increased by TGF-beta as well as by coculturing with either astrocytes or Müller glial cells. Anti-TGF-beta antibody blocked the TGF-beta effect, but not the coculture effect on MMP-9 production. CONCLUSIONS: These data indicate a direct correlation between TGF-beta-induced MMP-9 activity and increased endothelial cell permeability. Moreover, endothelial cell production of MMP-9 is regulated by glial cells through expression of TGF-beta or by direct cell-to-cell contact. During retinal disease, glial cell production of active TGF-beta may contribute to breakdown of the blood-retinal barrier by stimulating endothelial cell MMP-9 production.

Animals↗
PubMed2001

Influence of an inducible nitric oxide synthase promoter variant on clinical variables in patients with coronary artery disease.

Pathophysiological processes in coronary artery disease (CAD) are influenced by genetic factors. Since (i) inducible nitric oxide synthase (iNOS) has important cardiovascular effects, and (ii) the promoter of the iNOS gene (NOS2A) is genetically modulated by a 4 bp insertion/deletion (+/-) polymorphism located 0.7 kb upstream, we decided to examine the influence of this variant on clinical variables in 856 CAD patients of Anglo-Celtic/Northern European extraction. We found that 2% of CAD patients were homozygous for the + allele, and 19% were heterozygous. Males made up 74% of the patient group, and in these the + allele was associated with 38% higher plasma glucose levels (P=0.005), a 4.8% elevation in the waist/hip ratio (P=0.009) and a 48% greater frequency of unstable angina (P=0.014). The + allele, by influencing iNOS expression, could thus contribute to indices of insulin resistance and angina severity in male CAD patients.

Aged↗
PubMed2001

Polymorphism in the gelatinase B gene and the severity of coronary arterial stenosis.

Gelatinase B, as one of the matrix metalloproteinases, may be relevant to atherogenic plaque development and stability. Recently, a C-1562T substitution in the regulatory region of the gelatinase B gene was shown to up-regulate gelatinase B expression, which could be relevant to both the severity and stability of atherosclerotic plaques. We determined the genotype of 788 angiographically documented Caucasian patients with coronary artery disease (583 males and 205 females; age 56.7+/-0.4 years). The proportions of C/C (77.1%), C/T (21.4%) and T/T (1.5%) genotypes were in Hardy-Weinberg equilibrium, and did not differ between males and females (P>0.05). The frequencies of the rare T allele in patients with angiographically documented coronary artery disease (0.123), a past history of myocardial infarction (0.128) or unstable angina (0.128) were not significantly different from those in patients without such events (0.121, 0.118 and 0.128 respectively; P>0.05). In addition, the rare allele frequencies among patients with no (0.128), one (0.124), two (0.108) or three (0.121) significantly diseased vessels (> or =50% luminal obstruction) were not statistically different (P=0.932). However, the male rare T/T homozygotes had lower waist/hip ratios and levels of high-density lipoprotein cholesterol (HDL-C), and higher total cholesterol/HDL-C ratios, than C/C homozygotes (P<0.05). In conclusion, our study in a large series of angiographically defined patients suggests that the C-1562T polymorphism may not be useful as a predictor of the presence and severity of coronary atherosclerosis.

Angina, Unstable↗
PubMed2001

Tibetan population data on the multiplex short tandem repeat loci--D16S539, D7S820, and D13S317.

The multiplex amplification system of three tetrameric short tandem repeats loci (D16S539, D7S820, and D13S317) have been analysed extensively in various populations for forensic application. Population genetic studies were carried out for these three loci in a population sample of 129 unrelated Tibetan individuals by using a multiplex polymerase chain reaction (PCR) followed by 4% polyacrylamide gel electrophoresis (PAGE) and silver staining. All loci were in accordance with the Hardy-Weinberg expectations. The observed heterozygosities of three loci-D16S539, D7S820, and D13S317 were 73.3%, 81.4% and 80.6%, respectively. The polymorphism information contents (PIC) were 0.84, 0.80 and 0.83, respectively. Comparing with Han population, there was no statistically significant difference except for D16S539 locus.

Chromosome Mapping↗
PubMed2001

[Estimation of phenotypic and genetic parameters for birth type and number of lambs born alive in hu sheep].

A total number of 458 litter records from 115 daughters of 26 stock rams collected at the Yuhang Hu Sheep Farm were analysed. The statistical analyses indicated that the proportion of 1 to 5 lambs per litter was 21.18%, 49.78%, 25.76%, 3.06% and 0.22%, respectively. Rams significantly influenced birth type and number of lambs born alive in the ewes. Parity didn't affect significantly birth type and number of lambs born alive. Birth type of the ewes did not significantly influence their number of lambs born alive. The estimated heritability was 0.251 for birth type and 0.097 for number of lambs born alive. The genetic, phenotypic and environmental correlations between birth type and number of lambs born alive were 0.241, 0.008 and 0.181, respectively. The coheritability for birth type and number of lambs born alive was 0.038. These parameters indicated that birth type and number of lambs born alive were two different traits which were not closely correlated genetically. Early selection for number of lambs born alive based on ewe birth type was ineffective.

Animals↗
PubMed2001

[The cytogenetical studies of fertility restoration of some male sterile lines of alloplasmic wheat].

The frequency of cells with univalent (FCU) at MI and with lagging chromosomes and chromosomal bridge (FCLB) at AI in PMC of F1 hybrids of 4 alloplasmic 1BL:/1RS and non-1BL/1RS wheat male sterile lines with Aegilops kotschyi, Ae. variabilis, Ae. ventricosa and Ae. bicornis cytoplasms were systematically investigated, and the relationship between FCU at MI, FCLB at AI and F1 selfed seed set was analyzed. The results were as follows: (1) The frequency of abnormal chromosomes at MI and AI was higher in 1BL/1RS hybrids than in non-1BL/1RS hybrids; (2) 4 alien cytoplasms had positive effects on the FCU at MI in non-1BL/1RS hybrids; (3) The effect of 1B.1BL/1RS hetero-nucleus on meiosis was more obvious than that of alien cytoplasms in 1BL/1RS hybrids; (4) The selfed seed set of 1BL/1RS hybrids was not correlated to FCU, but was negatively correlated to FCLB; (5) The chromosomes' deeds at meiosis was more steady in non-1BL/1RS hybrids than in 1BL/1RS hybrids. The non-1BL/RS hybrids were easy to restore and restoring degree was high, and they had good prospects to be used.

Chromosome Aberrations↗
PubMed2001

[Cloning of promoter of banana fruit-specific ACC synthase gene and primary study on its function].

Based on our cDNA sequence of ACC synthase gene expressed specifically in banana fruit, we cloned the 5'-flanking proximal region of 1197 bp and distal region of 1556 bp via walking on unknown region of genomic DNA by an improved adaptor ligation PCR, and created a 2591 bp fragment containing a promoter region of 2505 bp and a transcriptional region of 86 bp. The entire 2.5 kb promoter and 5 different 5' deletion variants were fused to the GUS (beta-glucuronidase) cDNA sequence and introduced into leaf, root and fruit cells of banana plant via particle bombardment separately. The results of transient gene expression assay indicated that the obtained promoter region could direct fruit-specific gene expression. The regulatory region for fruit-specificity was possibly located in the region from -1111 to +1 and a positive regulatory region may locate between nucleotide -1111 to -608.

Base Sequence↗
PubMed2001

[Cloning of promoter of banana fruit ripening-related ACO1 and primary study on its function].

According to the published sequence of ACC oxidase gene(ACO1) which was shown to express in banana fruits, we cloned its 5'-flanking region by improved adaptor ligation PCR. The 1526 bp fragment contained a putative TATA-box. Sequence alignment of our promoter with two published (934 bp and 1451 bp) revealed 97.3% (López-Gómez et al.) and 88.8% (May and Kipp) similarity in nucleotide sequence, respectively. The 5'-flanking fragments in different length were fused to the coding sequence of GUS gene. These constructs were delivered to leaf, root and fruit cells of banana via particle bombardment. The results of transient gene expression assay showed that the cloned ACO1 promoter was able to direct fruit-specific gene expression, and that the regulatory region for fruit-specificity was probably located in the 0.7 kb 5'-flanking sequence of the gene and some positive regulatory elements may exist within the region of 355 bp from 468 to 822.

Amino Acid Oxidoreductases↗
PubMed2001

Hypercholesterolemia alters vascular functions and gene expression of potassium channels in rat aortic smooth muscle cells.

AIM: To investigate the effects of hypercholesterolemia on functions of rat aorta and on gene expression of inward rectifier and ATP-sensitive potassium channels in aortic smooth muscle. METHODS: Rats were treated with high-cholesterol emulsion ig for 2 weeks; the aortic rings with and without endothelium were prepared to examine the aortic contractile and relaxation responses; RT-PCR was used to observe the gene expression of inward rectifier and ATP-sensitive potassium channels. RESULTS: Hypercholesterolemia damaged the endothelium-dependent vascular functions severely, but did not affect the endothelium-independent vascular functions; Kir6.2 mRNA expression was upregulated (P < 0.05) and Kir3.1 mRNA expression was downregulated markedly (P < 0.05) in hypercholesterolemic smooth muscle. CONCLUSION: Hypercholesterolemia altered the vascular functions and regulated gene expression levels of specific inward rectifier and ATP-sensitive potassium channel subtypes.

Animals↗
PubMed2001

Atrophy and apoptosis in ventral prostate of rats induced by 5alpha-reductase inhibitor, epristeride.

AIM: To study molecular mechanism of epristeride in the treatment of benign prostatic hyperplasia and discuss the possibility of using prostate acid phosphatase (ACP) as a marker of the atrophy of prostatic gland in vivo. METHODS: Morphological changes in cells were observed by light microscope. TdT-mediated dUTP-biotin nick end labeling (TUNEL) technique and agarose gel electrophoresis were performed to detect the nucleosomal DNA fragmentation. The activity of pACP was also assayed. RESULTS: Apoptosis occurred in both castration- and epristeride- treatment group. Both the degree and extent of apoptosis are much larger in the group of castration than that of epristeride-treated group. Both epristeride and castration decreased the prostate wet weight and DNA content but increased the prostate DNA concentration. Maximal or near maximal decreases were seen by d 10 in both groups. The activity of ACP was decreased by both castration and epristeride treatment. Changes in the ACP activity during treatment were coincide with other changes such as the prostate wet weight and DNA content. CONCLUSION: Apoptosis induced by epristeride was one of mechanisms in the treatment of benign prostatic hyperplasia and the activity of ACP could be used as a marker of prostate atrophy.

5-alpha Reductase Inhibitors↗
PubMed2001

Inhibitory effect of aminoguanidine on bleomycin-induced pulmonary toxicity in rat.

AIM: To observe the inhibitory effect of aminoguanidine (AG) on the pulmonary toxicity induced by bleomycin A5 (BLM-A5) in rat. METHODS: The contents of hydroxyproline, nitrite/nitrate (NO2-/NO3-), and malondialdehyde (MDA), which reflect fibrosis, nitric oxide (NO) production, and hyperoxidative injury of lung, were investigated by colorimetry. Histologic and morphometric examination of lung was also carried out on histological sections stained with hematoxylin and eosin (HE). RESULTS: (1) The content of hydroxyproline in lung and MDA in out-going pulmonary blood (OPB) increased from 14 d to 30 d after intratracheal administration of BLM-A5. Collapsed alveoli and fibrotic areas were seen and a lot of fibroblasts appeared in the lung interstitum of the rats 30 d after BLM-A5. (2) The NO2-/NO3- content increased in supernatant of alveolar macrophage culture and in OPB. (3) The increment of hydroxyproline in lung and MDA in OPB induced by BLM-A5 was alleviated by aminoguanidine (AG, 20 mg.kg-1 . d-1, ip). AG also reduced the histologic and morphometric changes in lung interstitum. (4) The augment of NO2-/NO3- in OPB was blocked by AG. CONCLUSION: AG had inhibitory effect on pulmonary injury and fibrosis induced by BLM-A5, and the inhibitory effect was related to the decrease of NO production in lung.

Animals↗
PubMed2001

Inhibition of regrowth of prostatic glandular cells by epristeride.

AIM: To evaluate the ability of epristeride to inhibit the prostatic glandular regrowth. METHODS: Normal rats were castrated. Testosterone was injected to induce the regrowth of glandular cells. HE staining was performed. The height of the glandular epithelium and the acinar luminal areas were determined, and dihydrotestosterone (DHT) was detected by immunohistochemistry. RESULTS: Both the height and the acinar luminal areas were reduced by 48 % and 55 % in epristeride-treated group compared with control group respectively. The staining of DHT was comparatively strong in the control group. After 30-d of treatment, it turned much weaker. CONCLUSION: The regrowth of glandular cells was inhibited by epristeride via declining of the DHT concentration in the rat prostate.

5-alpha Reductase Inhibitors↗
PubMed2001

Promotion of pulmonary fibroblast proliferation and apoptosis by sodium nitroprusside.

The effects of nitric oxide (NO) donor sodium nitroprusside (SNP) on the proliferation and apoptosis and on Bcl-2, Bax and p53 proteins of pulmonary fibroblasts were investigated by using MTT cleavage assay, agarose gel electrophoresis and flow cytometric analysis. The results showed increases in the optical density (550 nm) of MTT cleavage assay, the number of cells and the proliferation index (PI), in comparison with the control. The number of apoptotic cells was also increased, though the percentage of apoptotic cells was too low to reveal oligonucleosomal fragmentation of characteristic ladder pattern, which is associated with apoptosis. In the meantime, the level of Bcl-2 decreased and that of Bax increased, while the p53 remained unchanged. These results suggest that exogenous NO has a dual effect on proliferation and apoptosis; and the action of NO on pulmonary fibroblasts is mainly proliferative. Down regulation of Bcl-2 and up regulation of Bax are implicated in the molecular mechanisms of this action.

Animals↗
PubMed2001

[Study on the forensic application of ABO genotyping by PCR-RFLP].

OBJECTIVE: The study was carried out on the application of ABO genotyping by PCR-RFLP to forensic purpose. METHODS: The DNA of samples were extracted by Chelex--100 and phenol/chloroform, the PCR products were separated by Native Horizontal PAGE, and detected by silver staining. RESULTS: The PCR amplified fragment length of ABO loci is from 175 to 210 bp, the frequency distribution of six genotypes ranges from 0.0250 to 0.4300, heterozygosity(H) and discriminating power(Dp) is 0.5162 and 0.7111. CONCLUSION: This technique has a good application to the forensic samples such as blood, blood stain, semen stain, hair root, bone tissue and semen from vaginal swabs.

ABO Blood-Group System↗
PubMed2001

[The ultrastructural study of synergids before and after fertilization in watermelon embryo sacs].

The ultrastructure of synergids of watermelon (Citrullus Lanatus L.) was investigated using transmission electron microscopy at following stages of embryo sacs: 1. Unpollination, on the first flowering day. 2. Unpollination, on 2nd day after anthesis (DAA). 3. Fertilization, on DAA 2. The synergids with distinct filiform apparatus at the micropylar end have abundant organelle, such as mitochondria, endoplasmic reticulum, and plastids in cytoplasm, which indicate that they are active on the first flowering day. No wall is present at the chalazal part of synergid, and there are some flocculent materials and vesicles in the spaces of cytoplasma membranes among synergid, egg cell and central cell in embryo sacs at the first and the second stages. On DAA 2, in unpollinated embryo sacs, the central large vacuole of synergid is divided into several smaller ones and the starch grains decrease in cytoplasm. There is no newly synthesized wall at the chalazal end of persistent synergid in fertilized embryo sacs. The contents of degenerated synergid, in the form of electron dense granules, are located in the wide space among central cell, zygote and persistent synergid, and some of them migrate into central cell through cytoplasma membrane. Therefore, it is deduced that the contents of synergid might serve as a nutrient supplement to the development of endosperm, but not embryo.

Citrullus↗
PubMed2001

[Efficacy of ablendazole emulsion in treatment of 212 patients with cystic echinococcosis].

OBJECTIVE: To verify the efficacy of abendazole emulsion, a new formulation of abendazole, in treatment of human cystic echinococcosis. METHODS: 212 patients with liver cystic echinococcosis were treated orally with albendazole emulsion at a daily dose of 10 mg/kg or 12.5 mg/kg for 3 to 12 months or over one year. The therapeutic efficacy was mainly evaluated by image feature examined with B ultrasound examination, a short-term efficacy at the completion of treatment and a long-term efficacy followed-up for 1-4 years. RESULTS: In 212 patients treated with albendazole emulsion at a daily dose of 10 mg/kg and 12.5 mg/kg, the average cure rate, improved rate and the rate of no avail were 74.5%, 99.1% and 0.9% respectively after termination of the treatment, and the average long-term rates were 83.1%, 89.3% and 0.6% respectively. Recurrence occurred in 18 patients(10.2%). The results indicated that the best efficacy was seen in patients treated with albendazole 12.5 mg/kg daily for 9 months. Better response was also found when the recurrent patients were re-treated with albendazole. CONCLUSION: The efficacy of albendazole emulsion on patients with liver cystic echinococcosis is much better than that of albendazole tablet or capsule and mebendazole. Meanwhile, the efficacy of albendazole emulsion is stable with less adverse effects. The results suggest that albendazole emulsion could be the drug of choice for treatment of cystic hydatid disease.

Albendazole↗