Biomedical subjects

C J Wang

Publications and source records attributed to C J Wang.

At least 37 records · Page 2Linked to original sources

PubMed2002

Extracorporeal shock wave promotes growth and differentiation of bone-marrow stromal cells towards osteoprogenitors associated with induction of TGF-beta1.

Extracorporeal shock-wave (ESW) treatment has been shown to be effective in promoting the healing of fractures. We aimed to determine whether ESW could enhance the growth of bone-marrow osteoprogenitor cells. We applied ESW to the left femur of rats 10 mm above the knee at 0.16 mJ/mm2 in a range of between 250 and 2000 impulses. Bone-marrow cells were harvested after ESW for one day and subjected to assessment of colony-forming unit (CFU) granulocytes, monocytes, erythocytes, megakaryocytes (CFU-Mix), CFU-stromal cells (CFU-S) and CFU-osteoprogenitors (CFU-O). We found that the mean value for the CFU-O colonies after treatment with 500 impulses of ESW was 168.2 CFU-O/well (SEM 11.3) compared with 88.2 CFU-O/well (SEM 7.2) in the control group. By contrast, ESW treatment did not affect haematopoiesis as shown by the CFU-Mix (p = 0.557). Treatment with 250 and 500 impulses promoted CFU-O, but not CFU-Mix formations whereas treatment with more than 750 impulses had an inhibiting effect. Treatment with 500 impulses also enhanced the activity of bone alkaline phosphatase in the subculture of CFU-O (p<0.01), indicating a selective promotion of growth of osteoprogenitor cells. Similarly, formation of bone nodules in the long-term culture of bone-marrow osteoprogenitor cells was also significantly enhanced by ESW treatment with 500 impulses. The mean production of TGF-beta1 was 610 pg/ml (SEM 84.6) in culture supernatants from ESW-treated rats compared with 283 pg/ml (SEM 36.8) in the control group. Our findings suggest that optimal treatment with ESW could enhance rat bone-marrow stromal growth and differentiation towards osteoprogenitors presumably by induction of TGF-beta1.

Alkaline Phosphatase↗

PubMed2001

Physical shock wave mediates membrane hyperpolarization and Ras activation for osteogenesis in human bone marrow stromal cells.

Physical shock wave (SW) has shown effectiveness on promotion of bone growth. We have recently demonstrated that SW could promote bone marrow stromal cell differentiation toward osteoprogenitor associated with induction of TGF-beta1. We have further demonstrated that SW-induced membrane hyperpolarization and Ras activation acted an early signal for the osteogenesis in human bone marrow stromal cells. An optimal dose of SW treatment at 0.16 mJ/mm(2) for 500 impulses induced a rapid membrane hyperpolarization in 5 min, activation of Ras in 30 min, and cell proliferation in 2 days. The SW-promoted cell growth was related to osteogenesis as demonstrated by increase of bone alkaline phosphatase activity in 6 days and osteocalcin mRNA expression in 12 days. In support that SW-induced Ras activation mediated osteogenesis of human bone marrow stromal cells, we further demonstrated that transfection of bone marrow stromal cells with a dominant negative Ras mutant (Asn-17 ras(H)) abrogated the SW enhancement of osteogenic transcription factor (CBFA1) activation, osteocalcin mRNA expression, and bone nodule formations. These results suggest that physical SW promotes bone marrow stromal cell differentiation toward osteogenic lineage via membrane hyperpolarization, followed by Ras activation and specific osteogenic transcription factor CBFA1 expression. A link between physical SW and biomembrane perturbation-mediated Ras activation may highlight how noninvasive physical agents could be used to promote fracture healing and to rescue patients with osteoporosis and osteopenic disorders in the future.

Bone Marrow Cells↗

PubMed2001

Modeling dynamically heterogeneous coupled relaxations.

A model describing dynamically heterogeneous relaxation in complex coupled systems is presented. The model predicts the splitting of a high-temperature single Debye relaxation to a low-temperature bimodal relaxation. The bimodal process shows a crossover from a Debye-type relaxation to an approximately stretched-exponential relaxation. Some general features of relaxation in complex systems emerge from the predictions of the model, and a comparison of the model with experiments is reported.

Journal Article↗

PubMed2001

Implications of quantitative tumor and nodal regression rates for nasopharyngeal carcinomas after 45 Gy of radiotherapy.

PURPOSE: To quantitatively investigate the clinical implications of tumor regression rate (TRR-45) and nodal regression rate (NRR-45) of nasopharyngeal carcinomas (NPC) after receiving 45 Gy of radiotherapy (RT). The values, predictive values, and associated factors of TRR-45 and NRR-45 in NPC are analyzed. METHODS AND MATERIALS: One hundred one patients with newly diagnosed NPC and who were curatively treated by RT alone were included in the study. Tumor volume and nodal volume before treatment and after 45 Gy were obtained from computed tomographic (CT) scans performed at those times and calculated with the assistance of a computer-based imaging analyzing system. TRR-45 (NRR-45) was defined as the ratio of reduced tumor (nodal) volume after 45 Gy to the initial tumor (nodal) volume. TRR-45 (NRR-45) values were stratified into three groups of slow (below 50%), moderate (between 50% and 75%), and rapid (above 75%) change. After conventional RT with 45 Gy, conformal RT for primary tumors was boosted to 70.2-72 Gy for T1-2 tumors, and 75.6-81 Gy for T3-T4 tumors. RT for residual neck masses was boosted by electron beam to 61-75 Gy. RESULTS: The mean value of TRR-45 for all patients was lower than that of NRR-45 for the 78 patients with metastatic neck nodes (70% +/- 4.8% vs. 81% +/- 5%, p = 0.003). The 3-year actuarial neck control rate was better than the primary tumor control rate with statistical significance (98% vs. 85%, p = 0.009). No significant statistical differences concerning local control probability, nodal control probability, or survival rate were found among patients with slow, moderate, or rapid TRR-45 or NRR-45. T-stage was the only significant prognostic factor for locoregional control after multivariate analysis. Tumor volume and T-stage were found to have a statistically significant negative correlation with TRR-45. No associated factor was found to be significantly correlated with NRR-45. CONCLUSION: Slow regression rates of the primary tumor or neck nodes in NPC after receiving 45 Gy of irradiation do not mean ultimately poor radiocurability, but may merely imply slow clearance of the cells damaged during irradiation. The different radiobiological behaviors of the regression rates during treatment, ultimate control probabilities, or associated factors for regression rates of NPC between primary tumors and neck nodes need to be further investigated.

Adult↗

PubMed2001

Gaseous nitric oxide-induced 8-nitroguanine formation in human lung fibroblast cells and cell-free DNA.

A time- and dose-dependent increase in 8-nitroguanine (8-NO(2)-G) was observed in human lung fibroblast cells (MRC-5) after treatment with gaseous NO-saturated buffer. It was also found that treatment with the inhibitor of inducible nitric oxide synthase (iNOS), N(G)-nitro-l-arginine methyl ester, significantly reduced the 8-NO(2)-G level in the gaseous NO-saturated buffer-treated MRC-5 cells. These results provide evidence indicating that NO gas causes DNA damage in mammalian cells, which involves the activation of iNOS and the subsequent generation of endogenous NO. On the other hand, a time- and dose-dependent increase in 8-NO(2)-G was also observed while DNA (isolated from MRC-5 cells) was incubated with gaseous NO-saturated buffer. These results suggest that part of the 8-NO(2)-G formation was due to direct modification of gaseous NO on DNA. Furthermore, an increase in nitrite concentration was found in both cell-free and MRC-5 cell-conditioned medium treated with gaseous NO-saturated buffer. Collectively, gaseous NO induced DNA damage by forming 8-NO(2)-G, a modification performed directly by the treated gaseous NO and indirectly by the following induction of endogenous NO. This effect might be an important pathway in genotoxicity of nitric oxides, and 8-NO(2)-G could act as a specific marker for DNA damage induced by gaseous NO, a common contaminatant in air pollution and cigarette smoke.

Biomarkers↗

PubMed2001

Induction of apoptosis by esculetin in human leukemia cells.

Esculetin, a coumarin compound, has been shown to exhibit antioxidant and anti-inflammatory effects. In the present study, esculetin was found to inhibit the survival of human promyelocytic leukemia HL-60 cells in a concentration-dependent and time-dependent manner. HL-60 cells underwent internucleosomal DNA fragmentation and morphological changes characteristic of apoptosis after a 24-h treatment with esculetin (100 microM). Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 40.93% after a 36-h treatment with esculetin (100 microM). Further investigation showed that esculetin induced the release of cytochrome c from mitochondria into cytosol in a time-dependent and concentration-dependent manner. Moreover, esculetin application reduced Bcl-2 protein expression to 58% after 9 h as compared with that time at 0. Cysteine protease 32 kDa proenzyme (CPP32), a caspase 3, was activated and its substrate, poly (adenosine diphosphate-ribose) polymerase, was cleaved after a 24-h treatment of HL-60 cells with esculetin. These data suggest that esculetin induces apoptosis in human leukemia cells by increasing cytosolic translocation of cytochrome c and activation of CPP32.

Antioxidants↗

PubMed2001

Effect of isoflurane versus nicardipine on blood flow of lumbar paraspinal muscles during controlled hypotension for spinal surgery.

STUDY DESIGN: This study compared the effects of isoflurane and nicardipine on regional blood flow of the lumbar paraspinal muscles. OBJECTIVES: The purpose of this study was to determine whether treatment with hypotensive agents result in ischemia of the lumbar paraspinal muscles, thereby facilitating surgical procedures. SUMMARY OF BACKGROUND DATA: Despite the general acceptance of controlled hypotension as effective in reducing blood loss during spinal surgery, the changes of blood flow that occur at the lumbar paraspinal muscles when this technique is applied remain unclear. The use of laser Doppler flowmetry allows changes of muscle blood flow to be easily detected in real time with minimal invasion, thereby allowing differences among distinct pharmacological approaches for induction and maintenance of controlled hypotension to be evaluated. METHODS: The prehypotensive and hypotensive (reduction of mean arterial pressure by 20 mm Hg) blood flow of the lumbar paraspinal muscles were assessed with a laser Doppler flowmeter in 40 patients undergoing lumbar spinal surgery. The first half of the patients (n = 20) received isoflurane, whereas the second half received nicardipine to achieve arterial hypotension. RESULTS: Compared with the prehypotensive state, during the hypotensive state, patients in the isoflurane group exhibited a 17% to 46% (mean, 33.7%) decrease in lumbar paraspinal muscle blood flow, whereas patients in the nicardipine group exhibited a 24% to 177% (mean, 82.5%) increase in lumbar paraspinal muscle blood flow. Statistical analysis showed a significant difference in the changes of flux after induced hypotension between the isoflurane and nicardipine group (P < 0.001). CONCLUSIONS: Depending on the pharmacological treatment used to achieve arterial hypotension in spine surgery, there will be either a reduction in paraspinal muscle blood flow (ischemia) or an enhancement of this blood flow (hyperemia).

Adult↗

PubMed2001

Increased expression of iNOS and c-fos via regulation of protein tyrosine phosphorylation and MEK1/ERK2 proteins in terminal bronchiole lesions in the lungs of rats exposed to cigarette smoke.

Epidemiological evidence suggests that smoking is a major cause of human lung cancer. However, the mechanism by which cigarette smoke induces the cancer remains unestablished. To evaluate the effects of cigarette smoke on the expression of inducible nitric oxide synthase (iNOS), nuclear protooncogenes and related mitogen-activated protein kinases (MAPKs) in rat lung tissue, a histopathological study of the effects of gas-phase cigarette smoke on rat lung tissue were carried out. The terminal bronchioles were found to be infiltrated predominantly by lymphocytes in the peribronchiolar region and a mild to moderate degree of emphysema was noted in the alveolar spaces. The terminal bronchioles also showed marked lipid peroxidation, dilatation, and peribronchiolar fibrosis. Immunohistochemical evaluation showed that the expression of iNOS, NF-kappa B, MAPKs (MEK1, ERK2), phosphotyrosine protein and c-fos was increased in the terminal bronchioles but protein kinase C (PKC), MEKK-1, c-jun, p38 and c-myc showed no change. These results provide evidence to suggest that exposure to cigarette smoke results in oxidant stress which leads to the stimulation of iNOS and c-fos together with the induction of protein tyrosine phosphorylation and MEK1/ERK2 which in turn may promote lung pathogenesis.

Animals↗

PubMed2001

Acute septic arthritis of the hip in children.

Thirty-three cases of acute septic arthritis of the hip in children were treated at our hospital from 1986 to 1997. The average follow-up period was 6 years (range 2-11 years). In 17 cases the right hip was affected, and in 16 the left hip. The average duration of symptoms was 5 days (range 1-14 days). Microorganisms were isolated from the blood, joint aspirate, or surgical specimens in 25 cases (76%). Staphylococcus aureus was the most common bacteria found (44%). Those patients with S. aureus infection were older than 1 year of age. There was no significant difference in the final outcome between the younger and the older age groups. Twenty-six out of 33 patients (89%) had a satisfactory outcome. Satisfactory results can also be expected with arthrocentesis and medical treatment if the diagnosis is made early, and antibiotic treatment affords a good clinical response. Four out of 7 cases with an unsatisfactory result were associated with osteomyelitis of the proximal femur. The two most important factors associated with poor results included a delay of definite treatment lasting longer than 5 days and the presence of osteomyelitis of the proximal femur.

Acute Disease↗

PubMed2001

Extraperitoneal approach to laparoscopic Burch colposuspension.

STUDY OBJECTIVE: To evaluate 3-year outcomes of extraperitoneal laparoscopic colposuspension in treating genuine stress incontinence. DESIGN: Retrospective review (Canadian Task Force classification II-2). SETTING: University-based, tertiary-level center for endoscopic surgery. PATIENTS: One hundred sixty women with genuine stress incontinence with bladder neck hypermobility. INTERVENTION: Extraperitoneal space was created with CO2 through a 10-mm midline port 2 cm above the pubic hairline. A pair of sutures was inserted at the level of midurethral and urethrovesical junction, fixing them to Cooper's ligament on each side with proper tension. MEASUREMENTS AND MAIN RESULTS: Of 160 women, 10 were lost to follow-up. On follow-up questionnaire sent to 150 patients, 148 (98.7%) were pleased with the results of surgery. Stress incontinence was cured in 136 women (90.7%) after a minimum of 3 years' follow-up. CONCLUSION: Cure rates for extraperitoneal colposuspension were similar to those reported for traditional laparoscopic or laparotomy Burch procedures; however, this is a more direct method to expose the space of Retzius, thus eliminating the need to open and close peritoneum.

Adult↗

PubMed2001

Classification for endoscopic treatment of mullerian anomalies with an obstructive cervix.

STUDY OBJECTIVE: To describe our classification according to severity of developmental mullerian anomalies with obstructed cervix. DESIGN: Retrospective review (Canadian Task Force classification II-2). SETTING: University-based, tertiary-level center for endoscopic surgery. PATIENTS: Ten women with developmental mullerian anomalies with obstructed cervix. INTERVENTION: Patients with didelphic uterus with a rudimentary nonfunctional horn and hypoplastic cervix (type 1) underwent hemihysterectomy or diagnostic endoscopy. Those with agenesis of cervix with normal uterus (type 2) had uterovaginal canalization or neocervix with full-thickness skin graft. Women with identical didelphic uteri and hypoplastic cervix (type 3) underwent uterovaginal canalization with or without endometrial ablation or hemihysterectomy. Patients with didelphic uterus with a rudimentary horn and hypoplastic cervix (type 4) had laparoscopic hemihysterectomy. Those with agenesis of the vagina and cervix but with functional endometrium (type 5) had laparoscopic-assisted full-thickness skin graft. MEASUREMENTS AND MAIN RESULTS: Average duration of surgery was 60 to 210 minutes. There were no intraoperative complications. Patients with type 1 anomaly are continuing infertility treatment. All three patients in type 2 continue to have regular menses without dysmenorrhea. In those with type 3 conditions, hemihysterectomy was performed in one woman and uterovaginal canalization was performed on the hypoplastic cervix in another. After the neocervix was created, endometrial ablation was performed. No evidence of cervical obstruction or hematometra was found in either patient. The patient with type 4 anomaly continues to have regular menstrual periods without dysmenorrhea. Women with type 5 disorder had good healing of vaginal skin grafts. CONCLUSION: This classification helps identify mullerian anomalies in relation to obstructive cervix. It is useful in categorizing the disorders and determines management strategies and prognosis.

Adolescent↗

PubMed2001

Laparoscopic closure of patent canal of Nuck for female indirect inguinal hernia.

STUDY OBJECTIVE: To determine the efficacy of concomitant laparoscopic closure of the patent canal of Nuck in treatment of indirect inguinal hernias in women. DESIGN: Prospective clinical trial (Canadian Task Force classification II-2). SETTING: University-associated tertiary care referral center. PATIENTS: Six women scheduled for laparoscopy for gynecologic indications. Intervention. Concomitant simple closure of the patent canal of Nuck from the peritoneal cavity during laparoscopic surgery. MEASUREMENTS AND MAIN RESULTS: Inguinal hernias were repaired in all six patients, with no recurrence. CONCLUSION: l Laparoscopic closure of the patent canal of Nuck is an easy, safe, and effective treatment of indirect inguinal hernias in women. (J Am Assoc Gynecol Laparosc 8(1):143-146, 2001)

Adult↗

PubMed2001

A new portal for gynecologic laparoscopy.

We used the middle upper abdomen as a primary port insertion as an alternative portal for laparoscopy and multiport operative pelviscopy in 188 women who were at high risk for subumbilical adhesions because of previous abdominal surgeries or history of gynecologic cancer. Primary cannula insertion was in the middle upper abdomen between xyphoid process and umbilicus (Lee-Huang point). This was the single entry site for the Veress needle and primary laparoscopy port. In 184 (98.4%) of 188 women surgery was performed without complications. No procedure was converted to laparotomy due to visceral or vascular injuries. Two omentum injuries from primary port insertion were repaired with bipolar electrocoagulation; a colon injury was repaired with laparoscopic sutures. In our experience, this laparoscopic port is effective in women who have had abdominal surgery or gynecologic malignancy. (J Am Assoc Gynecol Laparosc 8(1):147-150, 2001)

Adult↗

PubMed2001

Uterovaginal canalization and endometrial ablation of the obstructed uterine horn with hypoplastic cervix in the didelphic uterus.

Maldevelopment of the mullerian duct system may result in various urogenital anomalies including didelphic uterus with a hypoplastic cervix. Two women with this anomaly experienced symptoms including recurrent lower abdominal pain off and on of 1 to 2 years' duration. Magnetic resonance imaging revealed a double uterus with right hematometrium both patients. After hysteroscopic identification of hypoplasia of right uterine cervix, laparoscopic resection of the hematosalpinx, followed by uterovaginal canalization and prophylactic endometrial ablation of the right uterus was successfully performed by resectoscope. Normal menstruation ensued during follow-up of 18 and 24 months, respectively. Our experience suggests that uterovaginal canalization with prophylactic endometrial ablation may be an efficacious alternative to hysterectomy for management of didelphic uterus with a hypoplastic cervix. (J Am Assoc Gynecol Laparosc 8(1):151-153, 2001)

Abdominal Pain↗

PubMed2001

Tumor-promoting effect of GGN-MRP extract from the Maillard reaction products of glucose and glycine in the presence of sodium nitrite in C3H10T1/2 cells.

GGN-MRP is an extract from the Maillard reaction products of nitrite with glucose and glycine in the Maillard browning system. No genotoxicity of GGN-MRP in culture hepatocyte was found. A two-stage transformation protocol was used to transform chemically mouse embryo fibroblast C3H10T1/2 cells. To initiate transformation, the cells were treated with benzo[a]pyrene [B(a)P; 0.1 microg/mL], and GGN-MRP (0.01, 0.1, and 1.0 mg/mL) was employed to subsequently complete the transformation process. Malignant transformed foci were formed in B(a)P-initiated and GGN-MRP-promoted C3H10T1/2 cells after 8 weeks. Cells treated with GGN-MRP alone failed to induce transformation. However, cells initiated with B(a)P and promoted by GGN-MRP demonstrated oncogenic properties. Transformed colonies derived from GGN-MRP-treated cells exhibited enhanced growth rate, anchorage independence, and tumorgenicity in animals relative to parent cells. These results indicated that GGN-MRP contains a tumor promoter and may induce tumor promotion by two-stage oncogenesis.

Animals↗

PubMed2001

ASSESS-3: a randomised, double-blind, flexible-dose clinical trial of the efficacy and safety of oral sildenafil in the treatment of men with erectile dysfunction in Taiwan.

The efficacy and safety of sildenafil were evaluated in a randomised, double-blind, placebo-controlled, flexible-dose study in Taiwanese men aged 26 to 80 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months' duration. A total of 236 patients were randomised at six medical centres in Taiwan to receive either sildenafil (50 mg initially increased if necessary to 100 mg or decreased to 25 mg depending on efficacy and toleration) (n=119) or matching placebo (n=117) taken on an 'as needed' basis 1 h prior to anticipated sexual activity for a period of 12 weeks. At the end of 12 weeks, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the IIEF (International Index of Erectile Function) scale, (2) the percentage of successful intercourse attempts; and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P<0.0001). Treatment-related adverse events occurred in 43.7% of patients receiving sildenafil and 18.8% receiving placebo. The most common adverse events with sildenafil were flushing, dizziness and headache (25.2, 6.7 and 5.9% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in the population of Taiwanese men appears similar to that reported in other studies in western populations.

Administration, Oral↗

PubMed2001

Concomitant closure of patent canal of Nuck during laparoscopic surgery: case report.

Indirect inguinal hernia is neglected by many female patients. When women undergo laparoscopy for infertility work-up or other gynaecological conditions, the hernia appears pressurized by the pneumoperitoneum. A large opening on the peritoneum followed by the patent canal of Nuck-as seen in the patient in this case report-is accompanied by a bulge above the labia major. This situation was treated with simple ligation of the canal of Nuck from the internal inguinal ring, and the vulvar bulging mass quickly disappeared, even while under pneumoperitoneal pressure. Laparoscopic hernia repair is currently performed with a mesh prosthesis to cover the defect; however, in female patients it seems unnecessary to use such an invasive method designed largely for males. According to our experience, the concomitant simple closure method for female indirect inguinal hernia is a quick and simple procedure, and deals with the problem during the same laparoscopy. In addition, disappearance of the bulging mass under the pneumoperitoneum offers a useful diagnostic test to secure hernia management.

Adult↗

PubMed2001

Treatment of calcifying tendinitis of the shoulder with shock wave therapy.

In a prospective clinical study, the effectiveness of shock wave treatment for calcifying tendinitis in 31 shoulders in 29 patients (14 women and 15 men) with an average age of 52 years was assessed. Each shoulder was treated with 1,000 impulses of shock waves at 14 kV. A 100-point Constant score system was used for evaluation. The overall results of 20 patients (21 shoulders) with 12 weeks followup were no complaints in 23.8%, significantly improved in 38.1%, some improvement in 14.3%, and unchanged in 23.8%. Considerable improvement was observed between 6 and 12 weeks. The results of seven patients with 24 weeks followup were no complaints in two patients, significantly improved in three, and unchanged in two patients. Radiographs showed complete elimination of the calcium deposits in six patients (28.6%), incomplete elimination in two patients (9.5%), and three patients (14.3%) had fragmentation of the calcium deposits. There was no recurrence of calcium deposits observed at 24 weeks. There was a correlation between the functional improvement and the elimination of calcium deposits. There were no device-related problems, systemic or local complications. Low-energy shock wave therapy may offer a new and safer additional nonoperative treatment for patients with calcifying tendinitis of the shoulder.

Adult↗