Biomedical subjects

Long-Cheng Li

Publications and source records attributed to Long-Cheng Li.

25 records · Page 2Linked to original sources

PubMed2004

Retroperitoneoscopic subcapsular nephrectomy for infective nonfunctioning kidney with dense perinephric adhesions.

OBJECTIVE: To evaluate the feasibility and clinical efficacy of retroperitoneoscopic subcapsular nephrectomy for infective nonfunctioning kidneys with dense perinephric adhesions. PATIENTS AND METHODS: Twelve patients underwent retroperitoneoscopic subcapsular nephrectomy; the operative duration, blood loss, intestinal functional recovery time, complications during surgery and efficacy were recorded. Dissociation and ligation of the renal pedicle was the most important step, at which the renal capsule was cut near the renal hilum using a harmonic scalpel, and the fatty tissue around the renal hilum dissected carefully. The renal pedicle was then ligated and divided using an endoscopic linear stapler-cutter after the renal pedicle tissues had been separated to an adequate thickness. RESULTS: All 12 operations were successful and none required conversion to open surgery. The mean (SD, range) operative duration was 82.9 (22.3, 45-120) min, the blood loss 51.4 (12.2, 30-75) mL and the intestinal functional recovery time 12-48 h. There were no complications during or after the surgery, and in the follow-up of 1-15 months the short-term results were satisfactory. CONCLUSION: Retroperitoneoscopic subcapsular nephrectomy can be used safely to remove an infected and heavily adhesive nonfunctioning kidney, with minimal trauma and blood loss, and with faster recovery than after an open subcapsular nephrectomy.

Adult↗

PubMed2003

PGDB: a curated and integrated database of genes related to the prostate.

The Prostate Gene Database (PGDB: http://www.ucsf.edu/pgdb) is a curated and integrated database of genes or genomic loci related to the human prostate and prostatic diseases. Currently, PGDB covers genes involved in a number of molecular and genetic events of the prostate including gene amplification, mutation, gross deletion, methylation, polymorphism, linkage and over-expression, as published in the literature. Genes that are specifically expressed in prostate, as evidenced by analysis of data from expressed sequence tags (ESTs) and serial analysis of gene expression (SAGE), are also included. There are a total of 165 unique entries in the database. Users can either browse or query the PGDB through a web interface. For each gene, in addition to basic gene information and rich cross-references to other databases, inclusive and relevant literature references are provided to support the inclusion of the gene in the database. Detailed expression data calculated from the UniGene and SAGEmap databases are also presented.

Databases, Genetic↗

PubMed2003

Comparison of open surgery versus retroperitoneoscopic approach to chyluria.

PURPOSE: We compared the clinical effectiveness of renal pedicle lymphatic disconnection for chyluria performed by retroperitoneoscopy and by open surgery. MATERIALS AND METHODS: Three male and 4 female patients 33 to 68 years old (mean age 49) with chyluria underwent retroperitoneoscopic renal pedicle lymphatic disconnection. Chyluria was on the left side in 5 cases and on the right side in 2. Open renal pedicle lymphatic disconnection was performed in 4 men and 2 women 33 to 61 years old (mean age 45.8). Chyluria was on the left and right sides in 3 cases each. Mean operative time, intraoperative blood loss, postoperative intestinal function recovery time, intraoperative and postoperative complications, postoperative hospital delay and operative outcome were compared in these 2 groups. RESULTS: Compared with the open surgery group results in the retroperitoneoscopic group were superior in terms of operative time (42 to 90 minutes, mean +/- SD 65.0 +/- 18.8 versus 120 to 220, mean 156.7 +/- 38.8), intraoperative blood loss (20 to 50 ml., mean 29.3 +/- 10.2 versus 60 to 250, mean 171.7 +/- 76.5), postoperative intestinal function recovery time (24 to 48 hours, mean 36.0 +/- 6.9 versus 24 to 72, mean 54.0 +/- 21.1), intraoperative and postoperative complications, and postoperative hospital stay (3 to 6 days, mean 4.7 +/- 0.7 versus 7 to 9 days, mean 7.8 +/- 1.0). In the open surgery group primary anastomosis was performed in 1 case due to injury to a renal artery branch during the operation. Chyluria resolved the day after surgery in the 2 groups. No obvious complications developed postoperatively. The followup of 2 to 12 months (mean 6.7 +/- 4.0) showed no recurrence of chyluria. CONCLUSIONS: Retroperitoneoscopic renal pedicle lymphatic disconnection completely ligates the lymphatic vessels with minimal invasion, less blood loss, rapid recovery and a good short-term outcome.

Adult↗

PubMed2003

Association between a C/A single nucleotide polymorphism of the E-cadherin gene promoter and transitional cell carcinoma of the bladder.

PURPOSE: We investigated whether a C/A single nucleotide polymorphism at position -160 from the transcription start site of the E-cadherin gene promoter is associated with transitional cell carcinoma of the bladder (TCCB). MATERIALS AND METHODS: A hospital based case-control study was performed in 50 patients with TCCB, including 38 men and 12 women 33 to 72 years old (mean age 53.8 +/- 12.3), and 50 normal controls, including 31 men and 19 women 22 to 69 years old (mean age 48.9 +/- 13.1). Genomic DNA was extracted from subject blood samples. Genotypes were determined using polymerase chain reaction based restriction fragment length polymorphism technique. RESULTS: A allele frequencies at the -160 position of the E-cadherin gene promoter were significantly higher in TCCB than in normal controls (p <0.01). A allele carriers were at higher relative risk for TCCB than C only carriers (OR 4.16, 95% CI 1.74 to 9.93). AC and AA genotypes were associated with an increased risk of TCCB compared with CC genotypes (OR 3.48, 95% CI 1.26 to 9.63 and OR 4.91, 95% CI 1.79 to 13.45, respectively). A allele frequencies at the same position were also significantly higher in invasive TCCB than in superficial carcinoma (p <0.05). However, there was no statistical difference in A allele frequency between high and low TCCB pathological grades (p >0.05). CONCLUSIONS: The -160 C/A single nucleotide polymorphism of the E-cadherin gene promoter is associated with TCCB. This single nucleotide polymorphism may serve as a prognostic marker of TCCB.

Adult↗

PubMed2002

Transforming growth factor-beta(s) and their receptors in aging rat prostate.

We hypothesize that rat fetal urogenital sinus mesenchyme (UGM) can induce prostatic growth of growth quiescent adult rat prostate through modulations of TGFbetas and their receptors. To test this hypothesis, prostatic ducts from aging rat prostate (4, 12, 17, 22, and 27 months) were combined with fetal rat UGM and grafted under renal capsule of athymic nude mice. At 1, 3, and 5 months the tissue recombinants were harvested from renal capsule and analyzed for their growth. The gene and protein expression of TGFbeta1, 2, 3 and their receptors, TbetaR-I and TbetaR-II, were analyzed by RT-PCR and immunohistochemistry, respectively. The results of these experiments demonstrate that prostate ducts when combined with rat UGM formed larger grafts as compared to control (prostatic ducts without UGM). The older rat prostate recombinants (17, 22, and 27 months) formed larger grafts (159 mg/graft) as compared to younger rat prostate (4 and 12 months) grafts (51 mg/graft). The mRNA and protein expression for TbetaR-I and TbetaR-II in 22 and 27 months rat prostate tissue recombinants were significantly lower than 4, 12, and 17 month tissue recombinants. However, mRNA expression for TGFbeta1, TGFbeta2, and TGFbeta3 did not change with aging rat tissue recombinants. The protein expression for TGFbeta1 was significantly up-regulated whereas TGFbeta2 and TGFbeta3 were down-regulated with aging prostate tissue recombinants. The present study demonstrates for the first time that rat fetal UGM differentially induces growth of aging rat prostate in a tissue recombinant model. The mechanisms of induction may be through up-regulation of TGFbeta1 and down-regulation of TGFbeta2, and TGFbeta3. However, the action of TGFbetas may be through TbetaR-I and TbetaR-II independent pathways since these receptors were lacking or low in older rat prostate tissue recombinants. These findings are important in understanding the mechanisms of UGM mediated prostatic growth.

Activin Receptors, Type I↗

PubMed2002

CpG hypermethylation of promoter region and inactivation of E-cadherin gene in human bladder cancer.

Several studies have shown that E-cadherin expression is lost during malignant transformation. We hypothesized that CpG methylation in the promoter region may inactivate the expression of the E-cadherin gene in human bladder cancer. Normal and bladder cancer samples from 51 patients were compared in terms of E-cadherin gene expression and methylation status by immunohistochemistry, methylation-specific polymerase chain reaction (MSP), and bisulfite genome-sequencing techniques. Ten different CpG sites (nt 863, 865, 873, 879, 887, 892, 901, 918, 920, and 940) in the promoter region were studied. Thirty-five of 51 (69%) bladder cancer samples lacked E-cadherin expression, whereas only six of 51 (12%) normal bladder samples lacked E-cadherin immunoreactivity. MSP analysis of bladder cancer samples suggested that 43 of 51 (84%) showed methylation of the promoter region, whereas only 12 of 51 (24%) normal bladder samples showed hypermethylation. Sodium bisulfite genome-sequencing analysis revealed that of 10 CpG sites, two sites (nt 892 and nt 940) showed 100% methylation in all the cancer samples analyzed. Other CpG sites were partially methylated (47-91%). Normal tissue showed only 12% methylation (range, 1-33%) on various CpG sites. Also supporting these data, E-cadherin-negative bladder cancer cell lines restored expression of the E-cadherin gene after treatment with the demethylating agent 5-aza-2'-deoxycytidine. The present study showed that CpG hypermethylation was an important mechanism of E-cadherin gene inactivation in bladder cancer and also that specific CpG sites consistently presented higher methylation levels than others. These findings may provide a better strategy for the diagnosis and management of bladder cancer.

Aged↗

PubMed2002

MethPrimer: designing primers for methylation PCRs.

MOTIVATION: DNA methylation is an epigenetic mechanism of gene regulation. Bisulfite- conversion-based PCR methods, such as bisulfite sequencing PCR (BSP) and methylation specific PCR (MSP), remain the most commonly used techniques for methylation mapping. Existing primer design programs developed for standard PCR cannot handle primer design for bisulfite-conversion-based PCRs due to changes in DNA sequence context caused by bisulfite treatment and many special constraints both on the primers and the region to be amplified for such experiments. Therefore, the present study was designed to develop a program for such applications. RESULTS: MethPrimer, based on Primer 3, is a program for designing PCR primers for methylation mapping. It first takes a DNA sequence as its input and searches the sequence for potential CpG islands. Primers are then picked around the predicted CpG islands or around regions specified by users. MethPrimer can design primers for BSP and MSP. Results of primer selection are delivered through a web browser in text and in graphic view.

Base Sequence↗