Biomedical subjects

T M Wang

Publications and source records attributed to T M Wang.

At least 19 recordsLinked to original sources

PubMed2000

Expression of p16(INK4A) induces dominant suppression of glioblastoma growth in situ through necrosis and cell cycle arrest.

Tumor suppressor genes may represent an important new therapeutic modality in the treatment of human glioblastoma (GBM). p16(INK4A) is a tumor suppressor gene with mutation and/or deletion found in many human tumors, including glioblastomas, melanoma, and leukemias. RT-2 rat GBM cell line was used to investigate if the p16 gene induces dominant suppression of glioblastoma growth. Close to 100% of tumor cells were infected by high titer pCL retrovirus encoding the full-length human p16 cDNA at 5 m.o.i. Infected cells showed a 98% reduction in colony forming assay and a 60% reduction in growth curves in vitro compared to vector control. Exogenous overexpression of p16 induced hypophosphorylation of Rb protein by Western blot analysis. Intracranial injection of p16-infected tumor cells into syngeneic rats resulted in a 95% reduction in tumor volume compared to the controls. Intratumoral injection of p16 retrovirus resulted in tumor necrosis and prominent human p16 transgene expressions. Proliferation marker PCNA was not detected in these human p16-expressed RT-2 tumor cells, suggesting the cells were unable to enter into S phase after p16 expression. In addition, direct repeat intracranial injections of p16 retrovirus prolonged animal survival 3.2-fold compared to the controls (48.4 +/- 13.4 vs 15.0 +/- 2.1 days, p < 0.001). Two out of ten rats were found with dormant tumors at day 60 after p16 retrovirus injection. These results showed that p16 is effective in inhibiting GBM growth in situ. The mechanisms of tumor growth reduction and necrosis in vivo might be due to G1 arrest triggered by p16 expression.

Animals↗

PubMed1999

The implementation of clinical paths for six common urological procedures, and an analysis of variances.

OBJECTIVE: To evaluate the outcomes of treatment after implementing clinical paths for six common urological procedures, and analyse the variances from these paths. PATIENTS AND METHODS: The study comprised 1006 consecutive patients treated according to the recommendations of the clinical path for six common urological procedures; the results of treatment were compared with those from 1006 patients treated by the same physicians before implementing the clinical paths. Total admission charges were divided into five categories, i.e. operation and anaesthesia, laboratory, radiology, pharmacy and other. The differences in these five categories before and after implementation were determined; the variance data were also tracked and analysed. Five quality indicators were monitored during implementation and compared with the data before implementation. RESULTS: The mean length of hospital stay (LOS) and admission charges were significantly lower (P=0.03 and P<0.01) after implementation. The charges for laboratory, radiology, pharmacy and other were significantly decreased after the use of clinical paths. The common variations from the clinical paths were patient-related variance (33%) and discharge variance (26%). Variances affecting the LOS only or the admission charge only were more common than those affecting neither the LOS nor admission charges (both P<0.01), or both (both P<0.01). After implementation, the results of the five quality indicators were significantly improved and the number of patients with surgical complications was significantly reduced (P<0. 01), but the mortality and readmission rate did not increase. CONCLUSIONS: The implementation of clinical paths for six common urological procedures decreased the LOS, admission charges and surgical complications, and improved the quality of care. During implementation, variances can affect the LOS and/or admission charges.

Analysis of Variance↗

PubMed1999

Effects of implementation of 18 clinical pathways on costs and quality of care among patients undergoing urological surgery.

PURPOSE: We evaluated the effects on the costs and quality of care of implementation of 18 clinical pathways for urological operations. MATERIALS AND METHODS: From April 1997 to March 1998 patients undergoing 1 of 18 urological operations were treated according to clinical pathways. The outcomes in terms of length of hospital stay and admission charges of these patients were compared with those of patients treated between April 1996 and March 1997 before clinical pathways were implemented. We also selected 7 clinically relevant quality indicators to assess the quality of care before and after clinical pathway implementation. RESULTS: Of the 1,784 patients undergoing urological surgery from April 1997 to March 1998, 1,382 (77.5%) were treated according to 1 of the 18 clinical pathways. Before implementation 1,279 of 1,615 patients (79.2%) underwent these procedures. The length of hospital stay decreased from 5.5 to 4.9 days (p < 0.01) and the average hospital admission charges decreased by 12.9% (p < 0.01) after implementation. Five of the quality indicators, including the rate of surgical complications, were significantly improved after pathway implementation. The hospitalization rate was not affected (1.3 before versus 0.8% after implementation, p = 0.18). Variations from the clinical pathways occurred in 543 cases (39.3%) and affected the length of hospital stay only (11.6%) or the admission charge only (12.9%) more often than both (7.8%, p < 0.01) or neither (7.0%, p < 0.01). The most common variances in these patients were patient related (30.8%). CONCLUSIONS: Implementation of multiple clinical pathways in a urology department can improve urological practice by decreasing the length of hospital stay, admission charges and rate of surgical complications, and by improving the quality of care.

Adolescent↗

PubMed1999

Does the use of clinical paths improve the efficiency and quality of care under the case payment system for inguinal herniorrhaphy or transurethral prostatectomy?

BACKGROUND: We evaluated the effects of implementing clinical paths for both inguinal herniorrhaphy (IH) and transurethral prostatectomy (TURP) on the efficiency and quality of medical care under the case payment system. METHODS: Patients undergoing IH or TURP were treated using the guidelines for clinical paths under the case payment system (CPUCP). The results of treatment after implementation of CPUCP were compared with results for patients treated before implementation of CPUCP. We also compared results using eight quality indicators both before and after implementation of CPUCP. RESULTS: The post-CPUCP length of hospital stay decreased significantly in patients who underwent either IH (p < 0.001) or TURP (p = 0.008). The post-CPUCP total admission charges decreased (p = 0.001) by 7.5% in the IH group alone. Two quality indicators in the IH group and three quality indicators in the TURP group were significantly improved after implementation of CPUCP. The percentage of patients who completed treatment without deviation as recommended by the guidelines for CPUCP was about 60% in the IH group and about 70% in the TURP group. CONCLUSION: The results of this study indicate that the implementation of clinical paths under the case payment system for patients undergoing inguinal herniorrhaphy or transurethral prostatectomy can improve the efficiency and quality of medical care.

Critical Pathways↗

PubMed1999

Use of a medical decision support system to improve the preoperative diagnosis of prostate cancer with pelvic lymph node metastases.

BACKGROUND: We evaluated the effects of a medical decision support system on the preoperative diagnosis of prostate cancer with pelvic lymph node metastases. METHODS: The preoperative accuracy of staging prostate cancer with pelvic lymph node metastasis by the prostate cancer expert system (PCES) for 43 patients was compared to the accuracy of staging performed by 2 urological attending physicians and 5 residents, to test the validity of the PCES. The effect of PCES consultation on physicians' staging for prostate cancer with pelvic lymph node involvement was evaluated. RESULTS: In the diagnosis of prostate cancer with pelvic lymph node metastasis, PCES was significantly more accurate than the two attending physicians alone (p = 0.042; p = 0.008). All the urological residents' diagnoses were significantly less accurate than those of the PCES. After PCES consultation, all the urological residents increased diagnostic specificity significantly. Most residents usually used PCES for consultation only after the attending physician or department asked for the results. CONCLUSION: Owing to an increased ability for preoperative diagnosis of prostate cancer with pelvic lymph node metastasis, as supported by the PCES, some unnecessary pelvic lymphadenectomies may be avoided.

Aged↗

PubMed1998

Improvements in the efficiency of care after implementing a clinical-care pathway for transurethral prostatectomy.

OBJECTIVE: To investigate the efficiency of care, length of hospital stay and admission charges after implementing a clinical-care pathway for transurethral prostatectomy (TURP). PATIENTS AND METHODS: Changes in the length of hospital stay and admission charges were identified by comparing a series of 100 patients undergoing TURP and treated after implementing a clinical-care pathway with 100 patients treated by the same physicians before implementation. RESULTS: After implementing the care pathway, the mean length of hospital stay and admission charges were significantly lower (P < 0.01). The shorter length of stay was caused by a significant reduction (P < 0.05) in patient-related psychological/social delay after implementation. The number of laboratory tests and use of pharmacological agents were also significantly lower (P < 0.001) after implementation, with the decreases in these last variables significantly greater (P < 0.001) among junior physicians. CONCLUSIONS: The advantages of the TURP clinical-care pathway were the shorter hospital stay, arising from reduced patient-related psychological or social delay, and reduced admission charges consequent on the decreased use of laboratory tests and drugs, particularly for patients treated by junior physicians. These results suggest that physicians are likely to modify their management methods to improve efficiency when a clinical path is implemented.

Aged↗

PubMed1998

Improvement of medical care quality after implementation of a clinical path monitoring program for transurethral prostatectomy patients.

OBJECTIVES: The purpose of this study was to determine the effect on quality of care through the implementation of a clinical path for patients receiving transurethral prostatectomy. METHODS: We selected ten quality indicators with important clinical relevance as representative elements of the clinical path. These quality indicators were monitored during the entire hospitalization period of 100 consecutive patients who received transurethral prostatectomy. Monitoring data obtained from these patients were compared to data from 100 patients who received transurethral prostatectomy prior to implementation of the clinical path. Data was assessed to determine the relationship between quality indicators and management processes. RESULTS: Implementation of the clinical path for transurethral prostatectomy significantly decreased the percent of patients with incomplete preoperative tests on admission day, the duration of intravenous antibiotics administration, the percent of patients who required acute pain management postoperatively, the percent of patients who received postoperative bladder irrigation with normal saline and the percent of patients who had their Foley catheter removed after postoperative day 2. Three of the quality indicators had a significant relationship with management processes and may have directly affected the total admission charges. CONCLUSIONS: To evaluate the effect of the transurethral prostatectomy clinical path implementation on the quality of medical care, we compared ten quality indicators before and after implementation of this path. We concluded that implementation of the clinical path resulted in a statistically significant improvement in the quality of medical care.

Aged↗

PubMed1998

Squamous cell carcinoma of the bladder: a ten-year retrospective study.

BACKGROUND: There is a limited amount of information available on treatment efficacy and optimal management of squamous cell carcinoma of bladder. The goal of this study was to assess the long-term outcome of patients with squamous cell carcinoma of the bladder treated using different modalities. MATERIALS AND METHODS: Retrospective analysis of the medical records of 22 patients with squamous cell carcinoma of the bladder treated at Chang Gung Memorial Hospital from 1986 though 1996 was performed. The follow-up period ranged from 12 months to 111 months. RESULTS: The treatment modalities included transurethral resection in 7 patients, radical cystectomy with urinary diversion in 6 patients, preoperative radiation followed by total cystectomy in 8 patients, and partial cystectomy in one patient. The overall 5-year survival rate was 9%. Only 6 patients (27.3%) in this series were alive two years after diagnosis. Treatment using a combination of modalities including preoperative radiation followed by total cystectomy resulted in a 5-year survival rate of 12.5% in 8 patients. Total cystectomy alone in 6 patients resulted in a 5-year survival rate of 0%. However, the difference in survival rates between these 2 treatment groups was not statistically significant. CONCLUSION: Our results suggest that no definite significance concerning the role of preoperative radiation followed by total cystectomy could be drawn. The results were probably because most of our patients had locally advanced bladder cancer. Another consideration is the small sample size, which may have affected the significance. Although, cystectomy did not improve the 5-year survival rate of patients in this series, it improved the 2-year survival rate.

Adult↗

PubMed1998

The early effect of pelvic floor muscle exercise after transurethral prostatectomy.

PURPOSE: We evaluate the early effect of pelvic floor muscle exercise on the frequency of urination, terminal dribbling, urinary incontinence and satisfaction with life in patients after transurethral prostatectomy. MATERIALS AND METHODS: From February to October 1996, 50 patients who had undergone transurethral prostatectomy were selected for study. The first 25 men served as a control group and the next 25 were the experimental group. Pelvic floor muscle exercise was started after removal of the Foley catheter postoperatively in the experimental group. The patients were evaluated before pelvic floor muscle exercise and weekly at our outpatient department after discharge from the hospital. Results for the later 25 patients treated with the pelvic floor muscle exercise program were compared to those of the prior 25 patients. RESULTS: There was a statistically significant difference (p <0.05) in the strength of pelvic floor muscle contractions at 4 weeks, length of between void interval (p <0.01), terminal dribbling at week 4 (p <0.05) and urinary incontinence at weeks 3 and 4 between the 2 groups after pelvic floor muscle exercise. During this study no complication or mortality occurred and there were no cases of hospitalization for either group. After pelvic floor muscle exercise patients in the experimental group had better satisfaction with life than the control group (p <0.01). CONCLUSIONS: We conclude that pelvic floor muscle exercise seems to help reduce symptoms within the first 4 weeks after transurethral prostatectomy, and provides better psychological and social quality of life.

Aged↗

PubMed1997

Simultaneous determination of amoxycillin and clavulanic acid in pharmaceutical products by HPLC with beta-cyclodextrin stationary phase.

A simple, rapid and accurate method for simultaneous determination of amoxycillin and clavulanic acid using HPLC with beta-cyclodextrin stationary phase was developed. It involves the use of tetraethylammonium acetate (TEAA) as an additive reagent, methanol-buffer solution (pH 4.5) (35:65; v/v) as the mobile phase, detection at 225 mm and chromatogram within 12 min. Linearity and precision of the internal standard method have been obtained. Recoveries ranged from 99.25 to 105.63% for amoxycillin in the synthetic mixture. For clavulanic acid it was from 99.50 to 101.64%. This method is convenient and reproducible for analyses of these two components in different dosage forms.

Amoxicillin↗

PubMed1997

Susceptibility of Pseudomonas aeruginosa of various pyocin types to the newly synthesized ampicillin derivative, N-(6,7-difluoroquinolonyl)ampicillin.

Six hundred and thirty-two isolates of Pseudomonas aeruginosa of 17 pyocin types were collected in 1993 in Taiwan. Types 1, 10, 3, 35 and 12 were the most common pyocin types identified in Taiwan with isolation frequencies of 47.3%, 24.4%, 7.6%, 3.6% and 2.2%, respectively. Several pyocin subtypes were determined. All pyocin types (one isolate of each tested) were resistant to ampicillin and nalidixic acid, but sensitive to fluoroquinolone antibiotics, such as norfloxacin and enoxacin, indicating that cross-resistance to quinolone antibiotics of nalidixic acid and fluoroquinolone derivatives has not developed. A new ampicillin derivative of 6,7-difluoroquinolonic acid, N-(6,7-difluoroquinolonyl)-ampicillin (AU-1), was synthesized by coupling ampicillin with 6,7-difluoroquinolonic acid (FP-3). Compound AU-1 was much more active than either ampicillin or FP-3 alone against all pyocin types of P. aeruginosa and induced filamentation in most growing cells.

Ampicillin↗

PubMed1997

[Identification of Staphylococcus epidermidis by desferrioxamine susceptibility and trehalose fermentation tests].

The importance of coagulase-negative staphylococci, especially Staphylococcus epidermidis in clinical and nosocomial infection are recognized increasingly in recent years. A rapid and accurate identification of S. epidermidis is therefore important and necessary. A new test, susceptibility to desferrioxamine, coupled with trehalose fermentation has been recommended for the identification of this organism. However, the medium and method used are different from what has been recommended by the NCCLS. To investigate the feasibility of using the desferrioxamine susceptibility test in conjunction with the routinely used disc agar diffusion test, we employed 111 staphylococcal strains (including 51 S. epidermidis isolates, 15 S. hominis and 45 other coagulase-negative staphylococci) as test organisms, and followed the procedures recommended by the NCCLS in which Mueller-Hinton agar and standard inoculum were used. Results indicated that all strains of S. epidermidis and S. hominis were susceptible to 1 mg desferrioxamine (the diameter of the inhibition zone were 28-37 mm). The minimum inhibitory concentrations of desferrioxamine to S. epidermidis and S. hominis isolates were determined to be 125 micrograms/ml. Further differentiation of S. hominis and S. epidermidis can be made by their ability to ferment trehalose, the former could while the latter could not. We conclude that the desferrioxamine susceptibility test of coagulase-negative staphylococci can be used in conjunction with the routine disc agar diffusion method. S. epidermidis can be identified rapidly and accurately by its susceptibility to 1 mg desferrioxamine and inability to ferment trehalose.

Deferoxamine↗

PubMed1997

Use of the transurethral prostatectomy clinical path to monitor health outcomes.

PURPOSE: We evaluated the effect on cost and medical care quality of use of the transurethral prostatectomy clinical path. MATERIALS AND METHODS: Results in 100 patients treated when the transurethral prostatectomy clinical path was used were compared to those of 100 treated by the same physicians before implementation of this path. RESULTS: After implementation of the transurethral prostatectomy clinical path the length of hospital stay was significantly decreased from 5.9 to 5.0 days (p < 0.01) and Foley catheterization time was significantly decreased from 3.13 to 2.84 days (p < 0.01). Antibiotics were routinely used from the day before surgery to the day of hospital discharge as required by patient conditions. Therefore, a shorter hospital stay will significantly decrease the use of antibiotics. After implementation of the clinical path the average admission charges were decreased significantly by 17% (p < 0.01). Although some results from use of this path will not significantly affect costs, they will reflect some quality improvement. The effect of clinical path implementation on length of hospital stay between patients treated by junior and senior attending physicians was not significant. However, there was a statistically significant difference (p < 0.01) between results obtained by junior and senior attending physicians regarding average admission charges. CONCLUSIONS: Implementation of the transurethral prostatectomy clinical path can improve health care outcome by decreasing length of stay and admission charges, and improving quality of medical care, particularly for patients treated by junior attending physicians.

Aged↗

PubMed1997

Diagnosis of prostate cancer: comparison of serum prostate specific antigen, digital rectal examination and transrectal ultrasonography.

BACKGROUND: While prostate specific antigen (PSA) is useful as a tumor marker for monitoring patients with prostate cancer after definitive therapy, limitations have been noted when it is used for early detection of prostate cancer. METHODS: We reviewed the charts of 121 patients who had undergone prostate needle biopsies, documented digital rectal examination (DRE) and serum PSA determination before biopsy from January 1993 to October 1994. Indications for biopsy included abnormal DRE. PSA level greater than 4.0 ng/ml or abnormal lesions on transrectal ultrasonography (TRUS). RESULTS: Seventeen patients (14%) had stage A carcinoma with normal DRE and PSA levels from 0.1 to 34.9 ng/ml (mean 9.0 ng/ml). Four patients (3%) had stage B carcinoma with an average PSA level of 32.3 ng/ml and less than one lobe indurated on DRE. Six patients (5%) had stage C carcinoma and had an average PSA level of 48.5 ng/ml and less than one lobe indurated on DRE. Ninety-four (78%) patients had stage D carcinoma with an average PSA level of 120 ng/ml and more than one lobe indurated on DRE. While hypoechoic sectors were more than twice as likely as isoechoic sectors of the prostate to contain malignancy on biopsy, nearly 20% of cancers were found in isoechoic sectors. CONCLUSION: Serum PSA is the most accurate of the three diagnostic tests evaluated. The addition of DRE or TRUS improves the detection rate of prostate cancer over PSA alone.

Aged↗

PubMed1997

Retained vaginal gauze with unusual complication: a case report.

We report a case of a postpartum retained vaginal gauze which migrated to the bladder and presented as a bladder stone. The patient had received numerous clinical evaluations for her chronic abdominal pain, of all which failed to detect or indicate the presence of retained gauze. Retained surgical gauze is a preventable problem but continues to occur periodically. Prevention remains the key to this problem. The gauze packed within the vagina either after transvaginal surgery or delivery should be cared for as in other parts of the body. Though extremely rare, retained surgical gauze should be considered in the differential diagnosis in postpartum patients with chronic abdominal pain, irritable bladder symptoms or pelvic abscess.

Abdominal Pain↗

PubMed1996

Effects of 4-aminopyridine on saxitoxin intoxication.

Effects of 4-aminopyridine (4-AP) on neurotoxicity induced by saxitoxin (STX) are investigated in this study. In vitro, twitch tension evoked by nerve stimulation was depressed by STX (1.35 nM) in rat phrenic nerve-diaphragm preparations, and this inhibition was antagonized by 4-AP (0.1 mM). In addition, 4-AP (0.1 mM) restored the firing of membrane action potentials that were suppressed or even abolished by 0.334 nM STX in frog sartorius muscles. In vivo studies showed that 4-AP (0.3 mg/kg, iv) significantly reversed the respiratory rate, tidal volume, and blood pressure to normal values in anesthetized STX-toxicosis rats. Furthermore, 4-AP (0.75-6 mg/kg, ip) not only prolonged the survival time but also decreased the mortality of mice (71-43%) at a normally lethal dose (30 micrograms/kg, ip) of STX. The results suggest that 4-AP may be useful as an antidote for STX intoxication.

4-Aminopyridine↗

PubMed1996

Cytotoxic effects of anthrax lethal toxin on macrophage-like cell line J774A.1.

The cytotoxic effects of anthrax lethal toxin purified from an avirulent strain were examined on mouse macrophage-like J774A.1 cells. Cell death induced by high concentration of purified lethal toxin had the characteristics of necrosis. At lower concentrations, the toxin caused no morphological change and most of the cells were viable. Interestingly, apoptotic cells were observed when the cells were preincubated with a serine/threonine phosphatase inhibitor, calyculin A, and then exposed to a toxin concentration of 0.1 microg/ml. This is the first report that lethal toxin of the anthrax bacillus can induce both necrosis and apoptosis and that protein phosphatases are implicated in the regulation of bacterial toxin-induced apoptosis.

Animals↗

PubMed1996

Identification of immunodominant, group-specific and subcomplex-specific, continuous epitopes in the core regions of Japanese encephalitis virus using synthetic peptides.

Two flaviviruses, Japanese encephalitis (JE) virus and Dengue (DEN) virus which have high pathogenicity for humans, continue to pose a serious public health problem in tropical and subtropical countries of the world. In order to identify the immunodominant B-cell epitopes for diagnostic application, we have prepared a series of 15-mer synthetic peptides from JE virus core protein based on computer analysis. Four linear, immunodominant epitopes corresponding to amino acids 91-105 (P78), 1-15 (P73), 8-22 (P74), and 34-48 (P75) of JE virus core proteins were identified by employing an enzyme-linked immunosorbent assay (ELISA), using high-titered immune sera from JE-vaccinated children. P78 was found to be the most immunodominant. The sero-specificity of these peptides was tested by binding to seroconverted samples from JE and DEN-1 patients. P78 and P74 belonged to group-specific epitopes which reacted with both JE and DEN-1 patient sera. P73 and P75 belonged to subcomplex-specific epitopes which reacted only with JE but not with DEN-1 patient sera. The study suggests that these peptides corresponding to the immunodominant epitopes of JE virus core protein might have the potential to be used as peptide-based diagnostic reagents for the detection and differentiation of JE and DEN antibody responses.

Adult↗