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Biomedical subjects

Li Jiang

Publications and source records attributed to Li Jiang.

At least 37 records · Page 2Linked to original sources
PubMed2006

Scleral buckling procedures for longstanding or chronic rhegmatogenous retinal detachment with subretinal proliferation.

OBJECTIVE: To investigate longstanding or chronic retinal detachments (RDs) with subretinal strands and their clinical features and therapeutic effects using conventional retinal surgery. DESIGN: Retrospective, consecutive, noncomparative case series. PARTICIPANTS: Cases of 36 patients (40 eyes) with longstanding RD and subretinal proliferation who had undergone scleral buckling or encircling procedures between January 1, 1995 and October 31, 2003 at one institution were reviewed. METHODS: A retrospective analysis of the patient data was conducted from the medical records. MAIN OUTCOME MEASURES: Visual acuity (VA) and postoperative anatomic retinal reattachment at the final follow-up visit between 3 and 24 months (mean, 6.9). RESULTS: Forty eyes with an RD (mean duration, 13.8 months) treated with scleral encircling and buckling had a 90% cure rate after one surgery. The VA levels increased in 77.5% of eyes to over 5/100 at the final follow-up visit. Longstanding or chronic RD with subretinal proliferation had subretinal proliferative strands (i.e., a shallow RD) and a smooth atrophic detached retina, not a thickened retina. CONCLUSIONS: Our results suggest that scleral encircling and buckling can be used in most patients with a longstanding RD. The chronic pathologic course of longstanding rhegmatogenous RD should be considered before treatment.

Adolescent↗
PubMed2006

Retrospective survey of 452 patients with inflammatory bowel disease in Wuhan city, central China.

BACKGROUND: Inflammatory bowel disease (IBD) had been uncommon in China until about 1990, but since then, it has been seen in the clinical setting more and more. The prevalence and phenotype of IBD in the Chinese population is not well known. The present study investigates the trend of prevalence in ulcerative colitis (UC) and Crohn's disease (CD) in Wuhan City, central China, and evaluates clinical features, extraintestinal manifestations, and the treatment of IBD in the last 14 years. METHODS: Three hundred and eighty-nine patients with UC and 63 patients with CD were retrospectively collected from 5 central hospitals in Wuhan City, in which high-quality endoscopic and histological diagnoses were available from 1990 to 2003. UC and CD were diagnosed based on clinical, experimental, radiological, endoscopic, and histological examinations according to the internationally accepted Lennard-Jones criteria. RESULTS: The trend toward prevalence of UC and CD increased between 1990 and 2003 in Wuhan City. There was no change in the sex and age distribution comparing 1990 to 1996 with 1997 to 2003 both in UC and CD. However, the number of individuals with higher education and a professional occupation during 1997 to 2003 was significantly higher than that during the period 1990 to 1996 in patients with UC (OR 2.1, 95% CI 1.27-3.35, P = 0.004; OR 2.2, 95% CI 1.31-3.61, P = 0.003). The mean age of patients with CD was significantly younger than that of UC at the time of diagnosis (32.6 +/- 12.5 vs. 42 +/- 14.5, P < 0.0001). The ratio of male to female patients was 1.53:1 in UC and 2.32:1 in CD, respectively. The mean duration of onset of the disease to diagnosis was 1.4 years in UC and 1.1 years in CD. The extra intestinal manifestations of UC and CD were 5.7% and 19%, respectively, and complications of UC and CD were 6.4% and 50.8%, respectively. Only 3% of UC patients required surgery, whereas 27% of CD patients underwent surgical procedures (P < 0.001). CONCLUSION: The prevalence of IBD has increased in Wuhan City, central China, but is not as high as in Western countries. The disease in Wuhan City has often been associated with young adult professional males with a high level of education. The clinical presentation of UC was often mild and had few extra intestinal manifestations.

Adolescent↗
PubMed2006

Association of CTLA-4 gene microsatellite polymorphism with ulcerative colitis in Chinese patients.

Ulcerative colitis (UC) is characterized by chronic intestinal inflammation as a result of an exaggerated T cell response. Cytotoxic T lymphocyte associated antigen-4 (CTLA-4), expressed mainly in activated T cells, inhibits T cell activation and proliferation by combining B7 through competing CD28 and maintains immune homeostasis. Polymorphisms of the CTLA-4 gene are known to be associated with several autoimmune diseases. The aim of this study was to investigate the association between the CTLA-4 gene microsatellite polymorphism and UC in Chinese patients. Unrelated 100 Chinese patients with UC and 140 healthy controls were studied. The (AT) repeats in the 3' untranslated region of exon 4 of the CTLA-4 gene were amplified by allele-specific polymerase chain reaction (PCR). The amplified products were electrophoresed on a 12% polyacrylamide gel, followed by silver staining. Twenty alleles were found in Chinese patients and healthy controls. The 122-bp allele was increased in UC compared with healthy controls (9.5% vs 0.7%, P = 0.0001/Pc = 0.002, OR = 14.591, 95%CI 3.357-63.420). The frequency of the longer alleles (>or=118 bp) of UC was higher than that in healthy controls (26% vs 4%, P = 0.0001/Pc = 0.0002, OR = 7.644, 95%CI 3.950-14.792), but was not associated with location and severity of the disease. Furthermore, the longer alleles were not associated with haplotypes of C-318T/A+49G of the CTLA-4 gene in Chinese patients with UC. The longer alleles of the CTLA-4 gene microsatellite polymorphism were strongly associated with UC in Chinese patients.

Adolescent↗
PubMed2006

Shape-constraint region growing for delineation of hepatic metastases on contrast-enhanced computed tomograph scans.

OBJECTIVES: The objectives of this study were to develop a shape-constraint region-growing algorithm to automatically delineate liver metastases on computed tomography images and to compare automated tumor measurements with those outlined manually by radiologists. METHODS: The algorithm starts with a manual selection of a seed lesion region of interest (ROI). Based on intensity distributions of the seed ROI and the liver parenchyma, several parameters are computed and used to adaptively guide the region growing. To prevent the region growing from leaking into surrounding tissues of similar characteristics, specific shape constraints, including a local shape, a global shape, and a gravity-shift index, are developed to jointly control the iteration of the region growing. The algorithm was applied to 59 lesions in 14 patients with liver metastases. The maximal diameter (unidimension), the product of the maximal and maximal perpendicular diameters (bidimension), and the area in the axial plane were calculated for each of the segmented lesions. Three independent radiologists manually measured all the lesions once, and one of the radiologists measured each lesion 3 times. For each measurement, the concordance correlation coefficient (CCC) was used to assess the pairwise agreement between the computer and the different radiologists, and the overall concordance correlation coefficient (OCCC) was used to assess the agreement between the computer and the multiple radiologists and between the one radiologist's 3 readings. RESULTS: Fifty-three of 59 (89.8%) lesions in 14 patients with liver metastases were successfully segmented using this algorithm. The algorithm achieved a median accuracy of 88.0%. CCCs/OCCCs ranged from 0.943 to 0.999 with 95% confidence intervals. CONCLUSIONS: High accuracy and CCCs/OCCCs suggested that measurements made by the computer were very similar to those made by the radiologists.

Algorithms↗
PubMed2006

Contrasting genome-wide distribution of 8-hydroxyguanine and acrolein-modified adenine during oxidative stress-induced renal carcinogenesis.

Oxidative stress is a persistent threat to the genome and is associated with major causes of human mortality, including cancer, atherosclerosis, and aging. Here we established a method to generate libraries of genomic DNA fragments containing oxidatively modified bases by using specific monoclonal antibodies to immunoprecipitate enzyme-digested genome DNA. We applied this technique to two different base modifications, 8-hydroxyguanine and 1,N6-propanoadenine (acrotein-Ade), in a ferric nitrilotriacetate-induced murine renal carcinogenesis model. Renal cortical genomic DNA derived from 10- to 12-week-old male C57BL/6 mice, of untreated control or 6 hours after intraperitoneal injection of 3 mg iron/kg ferric nitrilotriacetate, was enzyme digested, immunoprecipitated, cloned, and mapped to each chromosome. The results revealed that distribution of the two modified bases was not random but differed in terms of chromosomes, gene size, and expression, which could be partially explained by chromosomal territory. In the wild-type mice, low GC content areas were more likely to harbor the two modified bases. Knockout of OGG1, a repair enzyme for genomic 8-hydroxyguanine, increased the amounts of acrolein-Ade as determined by quantitative polymerase chain reaction analyses. This versatile technique would introduce a novel research area as a high-throughput screening method for critical genomic loci under oxidative stress.

Acrolein↗
PubMed2006

[Changes in renal cell apoptosis and inflammatory cytokines in early stage of sepsis in rats].

OBJECTIVE: To investigate the relationship between changes in renal cell apoptosis and inflammatory cytokines in sepsis rats. METHODS: Sepsis was produced in rats by cecal ligation and puncture. Changes in tumor necrosis factor-alpha (TNF-alpha) and monocyte chemotactic protein-1 (MCP-1) levels in renal tissues were determined by enzyme-linked immunoadsorbent assay (ELISA), respectively. Meanwhile, apoptosis rate was also assessed by Annexin V/PI staining and flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL) methods. RESULTS: TNF-alpha and MCP-1 levels in renal tissues were significantly increased in rats with sepsis in the early stage. Apoptosis rate of renal cells increased and reached the highest level at 3 hours after sepsis was established and decreased after 6 hours, and the differences were significant (P<0.05 or P<0.01). CONCLUSION: TNF-alpha and MCP-1 are cytokines which are activated in early stage of sepsis. The increase in renal cell apoptosis in the early stage of sepsis is related with the release of cytokines.

Animals↗
PubMed2006

[Self-induction of rabbit marrow stromal stem cells into chondrocytes by transfection with reconstructed PGL3-transforming growth factor beta1 gene in vitro].

OBJECTIVE: To explore an experimental method of transfecting the marrow stromal stem cells (MSCs) with the reconstructed PGL3-transforming growth factor-beta1 (TGF-beta1) gene and to evaluate the feasibility of self-induction of MSCs to the chondrocytes in vitro so as to provide a scientific and experimental basis for a further "gene enhanced tissue engineering" research. METHODS: The rabbit MSCs was transfected with the reconstructed PGL3-TGF-beta1, gene by the Liposomes Method, the growth of the cells were observed, and the growth curve was drawn. The living activity of the transfected cells in the experimental group was evaluated by MTT, and the result was significantly different when compared with that in the control group. By the immunohistochemistry method (SABC), the antigens of TGF-beta1 and collagen II were examined at 2 and 7 days of the cell culture after transfection with PGL3-TGF-beta1 gene. The pictures of the immunohistochemistry slice were analyzed with the analysis instrument, and the statistical analysis was performed with the software of the SPSS 11.0, compared with the control group and the blank group. RESULTS: Transfection of the cultured rabbit MSCs in vitro with the reconstructed PGL3-TGF-beta1 gene by the Liposomes Method achieved a success, with a detection of the Luceraferase activity. The result was significantly different from that in the control group (P < 0.01). Tested by MTT, the living activity of the transfected cells was proved to be significantly decreased (P < 0.01 vs. the control group). By the immunohistochemistry method (SABC) to study TGF beta1, positive particles were detected in the experimental group, but there were no positive particles in the control and the blank groups. There was a significant difference between the two groups of the experiment and the control group based on the analysis of the t-test (P < 0.01). By the immunohistochemistry method (SABC) to study collagen II, there were more positive particles in the transfected cells in the experimental group than in the control and the blank groups, and there was a significant difference between the experimental group and the two other groups based on the t-test (P < 0.01). CONCLUSION: Transfection of the rabbit MSCs with the reconstructed PGL3-TGF-beta1 gene by the Liposomes Method is successful. There may be some damage to the cells when transfection is performed. The transfected BMS cells with PGL3-TGF-beta1 gene can express and excrete TGF-beta1 when cultured in vitro. The transfected MSCs that secret TGF-beta1 can be self-induced into the chondrocytes after being infected for 7 days when cultured in vitro.

Animals↗
PubMed2006

[Research of the spermatozoal gene expression with gene microarrays].

OBJECTIVE: To perform the detection of spermatozoal gene expression in order to accelerate the study of spermatozoal molecular biology. METHODS: To collect the healthy adults sperm and lymphocytes respectively, and then to extract the total RNAs from them by RNeasy mini kit (QIAGEN) or Trizol reagent. Corresponding cDNAs were produced, digested, ligated, finally labeled with Cy3 (sperm) and CyS (lymphocyte) in the course of RD amplifying reactions. Hybridization with self-made microarrays contained 560 probes was carried out after the labeled cDNAs pured by PCR Product Purification Kit. RESULTS: Among the 560 probes, 72 genes were up-regulated, 321 genes were down-regulated, the others had no different expression. Furthermore, genes associated with replication, transcription, translation and regulative functions were non-different expression or down-regulated, and those belonged to the spermatogenesis associated, sperm associated antigen were up-regulated, but those involved in the glycolysis were up-regulated, in the oxidative phosphorylation were down-regulated. CONCLUSION: It had successfully confirmed that there were a plenty of genes expressed in sperm, furthermore the genes expressed were accorded to spermatozoal functions and characteristics.

Adult↗
PubMed2006

[Effects of microRNA miR-181a on gene expression profiles of K562 cells].

OBJECTIVE: To investigate the effect of microRNA on the gene expression profile of human leukemia K562 cells using microarray technique. METHODS: miR-181a RNA duplexes were designed and synthesized according to the mature sequence of miR-181a. Forty-eight hours after transfection of in vitro cultured K562 cells using Oligofectamine, gene expression profiles of the cells were studied and analyzed using Agilent Human 1A Oligo microarray. RESULTS: Totalling 228 differentially expressed genes were identified from the 20,173 screened genes, including 59 up-regulated ones (consisting of metabolism-associated genes, tumor suppressor genes, signal transduction-associated genes, immunity and defense-associated genes etc), and 169 down-regulated ones (consisting of oncogenes, DNA-binding and transcription genes, metabolism-associated genes, signal transduction-associated genes, cell cycle and development-associated genes etc.) in the transfected K562 cells as compared with the control K562 cells. Changes in expressions of CTCF, ZAP70, SEMA4C and RALA were confirmed by semi-quantitative reverse transcription-polymerase chain reaction. CONCLUSIONS: miR-181a transfection for 48 h induces gene expression profile changes in K562 cells, indicating the functionality of the miR-181a. These differentially expressed genes are related to the functions of the microRNA, and may also be the basis of the regulation model of posttranscriptional gene silencing. These findings provide an evidence for further study of the machineries and functions of the microRNA in mammalian cells.

Gene Expression Profiling↗
PubMed2006

[Application of three-dimensional contrast-enhanced magnetic resonance angiography in renal artery angiography].

OBJECTIVE: To increase the probability of successful renal artery angiography with a three-dimensional contrast-enhanced magnetic resonance angiography (3D CE-MRA). METHODS: 3D CE-MRA was performed in 33 patients with hypertension. To calculate the scan delay time, a testing contrast agent bolus of 2 ml was injected for single sagittal slice real-time scanning, followed by oblique coronal 3D Fast TOF SPGRE. With maximum intensity projection, a set of images was acquired. RESULTS: Exact scan delay time was obtained in all the cases from which clear images were acquired with the exception of two cases in which failure of breath-holding occurred during the scanning. CONCLUSION: This examination enhances the performance by adopting elliptical-centric k-space recording for data acquisition for the center in k-space at the beginning of acquisition, and utilizing preceding testing bolus injection and signal intensity/time curve for determining the scan delay time, using slice selection and multiview image reconstruction.

Adolescent↗
PubMed2006

[Cloning and sequencing of the junction fragment of dystrophin gene with exons 3 to 5 deletion].

OBJECTIVE: To study the mechanisms of dystrophin gene deletion by cloning and sequencing the junction fragment of dystrophin gene with exons 3 to 5 deletion. METHODS: PCR was performed to verify dystrophin gene exons 3 to 5 deletion in a patient with Duchenne muscular dystrophy. A PCR-based genome-walking method was used to localize the breakpoint in introns 2 and 5, and the deletion-junction fragment was directly amplified by PCR approach with forward and reverse primers annealing to a DNA sequence as close as possible to the breakpoint in the introns 2 and 5. The sequencing result of the deletion-junction fragment was compared with the normal intron sequences. RESULTS: A sequence of 2113 bp containing the junction fragment was obtained. The 5' breakpoint was located in SINE/Alu element of intron 2, and the 3' breakpoint was located in the unique sequence near the sequence TTTAAA. The breakpoints were associated with a strong topoisomerase II cleavage site. A 26-bp fragment was inserted into the breakpoint and formed 3 duplications (GGCTTATATTTAA) of 13 bp around the deletion-junction fragment. CONCLUSION: Repeat sequence and strong topoisomerase II cleavage site around the breakpoint may predispose double-strand DNA breaks and recombination, which, in addition to the nonhomologous end-joining mechanism, may contribute as important factors to the gene deletion.

Adult↗
PubMed2006

[Loss of heterozygosity at chromosome 8p21-p23 in adenocarcinoma of gastric cardia].

Chromosome 8p21-p23 harbors tumor suppressor gene(s) implicated in multiple types of cancers. To investigate the involvement of the gene(s) in the carcinogenesis of adenocarcinoma of gastric cardia, loss of heterozygosity (LOH) for microsatellite markers at chromosome 8p21-p23 was examined. Laser capture microdissection (LCM) was used to obtain homogeneous tumor cells from 19 surgical specimens. Subsequently, genomic DNA extracted from the LCM-captured cells was amplified by multiple displacement amplification. Each tumor was assessed for allelic loss using 13 microsatellite markers. An overall LOH frequency of 63.2% (12/19) was observed and the LOH frequency for individual markers varied from 25% to 55.6%. One common deleted region of about 1.2 Mb (8p22GGAA-8p22ATCT) was defined. Our data indicated that the tumor suppressor gene at chromosome 8p22 might play an important role in the development of adenocarcinoma of gastric cardia.

Adenocarcinoma↗
PubMed2006

[Cytotoxic T lymphocyte antigen-4 promoter gene polymorphism is significantly associated with ulcerative colitis].

OBJECTIVE: Inflammatory bowel disease (IBD) is characterized by the T-cell excessive activation of intestinal mucosa. Cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) is a negative regulator of T-lymphocyte activation. The aim of the present study is to investigate the association between CTLA-4 promoter -1722 (T/C), -1661 (A/G) polymorphisms and ulcerative colitis (UC) in Han Chinese, in Hubei province of central China. METHODS: Eighty-seven patients with UC and 116 healthy controls were genotyped for CTLA-4 promoter -1722 and -1661 polymorphisms with a method of polymerase chain reaction based restriction fragment length polymorphism. RESULTS: The frequency of "A/G + G/G" genotype at the -1661 site was statistically higher in UC patients than in healthy controls (34.5% vs 15.5%, P = 0.002, OR = 2.865, 95% CI = 1.467-5.596). The frequency of the G allele at the -1661 site was also significantly higher in UC patients than in the controls (19.0% vs 8.2%, P = 0.002, OR = 2.624, 95% CI = 1.435-4.796). However, the distribution of the genotypes at -1722 site was not significantly different between the UC patients and the controls. CONCLUSION: The G allele of CTLA-4 promoter -1661 polymorphism showed a highly significant association with UC in Han Chinese of the central China.

Adult↗
PubMed2006

[A study on HLA-DQB1 allele associated with genetic susceptibility to duodenal ulcer in Guangdong Hans].

OBJECTIVE: To study the genetic susceptibility of HLA-DQB1 alleles to duodenal ulcer in Chinese Hans from Guangdong area around. METHODS: Hundred and five patients with duodenal ulcer and hundred and five healthy controls were examined for HLA-DQB1 genotypes. HLA-DQB1 allele typing was carried out by polymerase chain reaction with sequence specific primers (PCR-SSP). RESULTS: The allele frequency of HLA-DQB1*0602 in patients with duodenal ulcer (64.8%) was significantly higher than that in healthy controls (14.3%). CONCLUSION: These findings suggest that HLA-DQB1*0602 is a susceptible gene to duodenal ulcer in Guangdong Hans of China. And at HLA-DQB1 site, there are immunogenetic differences between duodenal ulcer patients and healthy controls.

Adolescent↗
PubMed2006

[A study on the situations of human L02 hepatocytes in genetically tolerized immunocompetent rats].

OBJECTIVE: To investigate whether human L02 hepatocytes could survive after implanting them into normal, immunocompetent rats. METHODS: Human L02 hepatocytes were injected through the uterine walls into the intraperitoneal cavities of fetal Sprague-Dawley rats to induce immune tolerance to human L02 hepatocytes. Human L02 hepatocytes stained with DiI were implanted into the spleens of the 2-week old rats. Immuno-fluorescent staining, SP immunohistochemistry, and DiI staining were used to detect human albumin and specific proliferating cell nuclear antigen (PCNA) in the rat livers. The distribution of human L02 hepatocytes was observed under the fluorescent microscope. RESULTS: Dynamic distribution of human L02 hepatocytes in the rat livers was observed from the 1st to the 10th week after the implantation. Human albumin was detected at 2, 4, 6 and 8 weeks, and at the 4th week it had the highest level. Specific human PCNA was detected in the rat livers from the 2nd to the 6th week after implantation. The PCNA positive cells were most abundant at the 4th week. CONCLUSION: Human L02 hepatocytes can survive and proliferate for 10 weeks after implanting them into genetically normal immunocompetent rats.

Animals↗
PubMed2006

[Relation between the decline of photosynthetic function and H2O2 accumulation in leaf life span of tobacco].

Correlations among H2O2 accumulation, chloroplast photosynthetic function decline and H2O2-scavenging enzymes of AsA-GSH cycle in leaf life span of tobacco (Nicotiana tabacum L. cv NC89) were studied. Photosynthetic rate displayed elevated phase,active photosynthesis duration and sharp fall phase while the chlorophyll content displayed elevated phase,relative steady phase and sharp fall phase during leaf life span. The decline of photosynthetic parameters was slow first and then sharp,and the decline of ribulose 1,5-bisphosphate carboxylase (RuBPCase) activity was obviously faster than that of photosynthetic electron transport activity during the decline of photosynthetic function. The decline of photosynthetic function was divided into reversible decline and irreversible decline. Ascorbate peroxidase (APX) and Glutathione reductase (GR) remained higher level in reversible decline stage,while declined fast in irreversible decline stage. H2O2 content was significantly negative correlated with chlorophyll content, photosynthetic rate, RuBPCase activity,APX and GR activity during the decline of photosynthetic function in tobacco leaves. Localized staining of H2O2 stated that the decline of photosynthetic function was closely correlative with H2O2 accumulation. The decline of photosynthetic function in tobacco leaves was faster than the decline of AsA-GSH cycle function.

Ascorbate Peroxidases↗
PubMed2006

[Study on therapeutic mechanisms of Danshen injection in intrahepatic cholestasis of pregnancy].

OBJECTIVE: To study the therapeutic mechanisms of Danshen injection in intrahepatic cholestasis of pregnancy (ICP). METHOD: The experimental serum was collected from 6 patients with ICP before therapy when in hospital. Endothelial cells were isolated from human umbilical veins chosen among the 10 normal pregnancy according to Jaffe's method. Serum of 20% concentration of ICP and different concentration of Danshen injection were cocultured with human vascular endothelial cells (HUVECs) for 24 hours. MTT method was applied to measuring the vitality of HUVECs. The expression value of vascular endothelial growth factor (VEGF) of different groups was detected by immunocytochemistry and enzyme-linked immunosorbent assay (ELISA) respectively. RESULT: Compared with ICP group, the value of MTT and VEGF in the Danshen injection therapeutic groups were increased with the increase of concentration and moreover, 8 g x L(-1) of Danshen injection was the optical concentration. By immunocytochemistry, the expression of VEGF in HUVECs in the Danshen injection therapeutic groups was also enhanced with the increase of concentration. CONCLUSION: Danshen injection can protect HUVECs against the injury of ICP serum and promote the expression of VEGF. Danshen injection improves HUVECs by increasing the value of VEGF.

Cells, Cultured↗