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Yat-Ching Tong

Publications and source records attributed to Yat-Ching Tong.

At least 19 recordsLinked to original sources
PubMed2006

Alterations of M(2)-muscarinic receptor protein and mRNA expression in the urothelium and muscle layer of the streptozotocin-induced diabetic rat urinary bladder.

Diabetes associated alterations of M2-muscarinic receptors (M2-mAChR) in the urothelium and muscle layer of the urinary bladder were studied using streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were divided into two groups; group I: normal control rats; group II: STZ-induced diabetic rats, 2 weeks after induction. The bladder was divided into urothelium and muscle layer by microdissection. Tissue M2-mAChR protein levels were measured by Western blotting. Expression of the mRNA that encoded M2-mAChR was estimated using the method of reverse transcription combined with polymerase chain reaction (RT-PCR). M2-mAChR protein and mRNA expressions were found in both the urothelium and muscle layer of the rat urinary bladder. In control rats, the M2-mAChR protein expression ratio in the urothelium and muscle layer was 1:1.66; that for mRNA was 1:0.97. Two weeks after induction of diabetes, the M2-mAChR mRNA expression in the urothelium and muscle layer were significantly increased by 44.4% (P<0.01, n=8) and 28.6% (P<0.01, n=8), respectively. Correspondently, the bladder M2-mAChR protein levels were significantly increased by 33.3% (P<0.001, n=8) in the urothelium and 25.3% (P<0.01, n=8) in the muscle layer of the diabetic rats. In conclusion, M2-mAChR mRNA and protein are expressed in both the urothelium and muscle layer of the rat urinary bladder. STZ-induced diabetes increases mRNA and protein expression of the M2-mAChR in the urothelium as well as the muscle layer.

Animals↗
PubMed2006

Chronic fluoxetine administration desensitizes the hyperglycemia but not the anorexia induced by serotonin in rats receiving fructose-enriched chow.

The present study examined the effect of chronic fluoxetine administration on the feeding behavior of fructose-fed rats. Male fructose-fed rats were divided into two groups: (1) control fructose-fed rats (CFR), and (2) fructose-fed rats treated with oral fluoxetine 5 mg/kg/day for 30 days (FFR). The feeding behaviors and plasma glucose levels in response to either serotonin (5-HT, 5 mg/kg) or saline injection were studied. The results showed 5-HT increased CFR plasma glucose in a dose-dependent fashion while FFR demonstrated significantly lower responses to 5-HT stimulation. 5-HT significantly increased the feeding latency and decreased the amount of food intake in the CFR. Fluoxetine treatment did not affect the 5-HT effect on food intake amount but significantly reduced the 5-HT effect on feeding latency. Putting the animals in a new environment increased the 5-HT effect on feeding latency further; the effect was ameliorated in the FFR. In conclusion, 5-HT induced hyperglycemia, increased feeding latency and decreased food intake amount in fructose-fed rats. Chronic administration of fluoxetine counteracted the 5-HT effects on blood glucose level and feeding latency, but not on the amount of food intake.

Animal Feed↗
PubMed2006

The effect of psychological motivation on volumes voided during uroflowmetry in healthy aged male volunteers.

AIMS: To study the effect of psychological motivation on the voided volume during uroflowmetry in aged-male volunteers. METHODS: An open contest of free-flow rate was held for the elderly community. People over 60 years old with no prior history of lower urinary tract symptoms were invited to compete. Participants were given the suggestion to void only when strong desire was experienced because greater the volume, faster the flow. One month later, 20 of the male participants were asked to come back for an office uroflowmetry, given the instruction to hold until strong desire was experienced. The results of the maximum flow rate, mean flow rate, and voided volume were compared between these two tests. RESULTS: In the first uroflowmetry, the average voided volume for the 20 participants was 532+/- 109 ml; maximum flow rate and average flow rate were 27.1+/- 9.4, and 17.2+/- 6.4 ml/sec, respectively. The voided volume decreased significantly in the second uroflowmetry (338+/- 82 ml, P<0.01); the maximum and average flow rates did not changed significantly (24.2+/- 9.5 and 14.9+/- 6.9 ml/sec, respectively). No participant had a shift of more than one standard deviation between the two tests on the Siroky's flow-rate nomogram. CONCLUSIONS: With psychological motivation to win the contest, the participants showed greater tolerance to bladder filling. This suggests that the state of mind can affect the perception on bladder sensation. On the other, the performance on emptying function is not significantly improved by motivation.

Aged↗
PubMed2006

A modified supine position to speed hand assisted retroperitoneoscopic nephroureterectomy: the Johnnie Walker position.

PURPOSE: To minimize the operative time of hand assisted retroperitoneoscopic nephroureterectomy by avoiding position change we report an especially designed surgical position. MATERIALS AND METHODS: A total of 41 patients with upper tract transitional cell carcinoma who underwent hand assisted retroperitoneoscopic nephroureterectomy and bladder cuff resection were enrolled. Patients lay supine, and the flank and hip on the lesion side were elevated 30 degrees. The legs were extended and abducted in the Johnnie Walker position, allowing the operator to stand between them. Operation was completed via a 7 to 8 cm Gibson incision and 2 additional laparoscopic ports. RESULTS: All procedures were successful except 1 open conversion due to bleeding, in which there was no need to reposition the patient. Average patient age was 65.2 years (range 34 to 85), mean operative time was 207.6 minutes (range 130 to 345) and mean estimated blood loss was 166 ml (range 50 to 900). Simultaneous transurethral endoscopic procedures were performed in 11 patients in the same position. Time to oral intake and ambulation was 2.1 and 2.0 days, respectively. Two patients had postoperative complications, including pneumonia and wound hematoma in 1 each. No complication was related to the position. CONCLUSIONS: The Johnnie Walker position minimizes operative time by eliminating the delay caused by patient positioning and draping changes, allowing better coordination for the surgeon and assistant, and permitting more efficient use of the nondominant hand. The retroperitoneal approach prevents bowel interference in the visual field, making laparoscopic surgery in this modified supine position possible. Nephroureterectomy, bladder cuff resection and endoscopic procedures can be done with ease with the patient in this position.

Adult↗
PubMed2006

Pumpkin seed oil and phytosterol-F can block testosterone/prazosin-induced prostate growth in rats.

INTRODUCTION: This study was undertaken to investigate the effects of pumpkin seed oil alone or combined with Phytosterol-F on testosterone/prazosin-induced (T-P) prostate growth in rats. MATERIALS AND METHODS: Forty adult Wistar rats were divided into five groups, including: one control group, rats treated with vehicle only, one group treated with T-P, and two groups of T-P-treated rats, one receiving orally pumpkin seed oil alone and one group receiving orally pumpkin seed oil combined with Phytosterol-F. Two weeks later, the prostatic weight-to-body weight ratio was determined after sacrifice. The total protein concentration was measured by using a protein assay. Some ventral prostatic tissues were histologically examined after hematoxylin-eosin staining. RESULTS: Histological sections of the ventral prostate showed that the architecture of the prostate glands became hyperplastic in the T-P rats, but not in the control or vehicle-treated animals. As compared with the control or vehicle group, T-P rats had a significantly higher prostatic weight-to-body weight ratio for the ventral prostate (p=0.05 and p=0.007, respectively), but not for the dorsolateral prostate (p=0.53 and p=0.73, respectively). The T-P rats had significantly higher protein levels within both lobes (ventral lobe, p=0.02 and p<0.0001, respectively; dorsolateral lobe, p=0.06 and p=0.005, respectively). As compared with the T-P-alone rats, the TP rats treated with pumpkin seed oil alone or pumpkin seed oil combined with Phytosterol-F had a significantly lower weight ratio for the ventral prostate (p=0.01 and p=0.004, respectively) and significantly lower protein levels within both lobes (p=0.03 and p=0.003, respectively; p=0.007 and p=0.002, respectively). In addition, Phytosterol-F had some additive effect on the total protein synthesis within the ventral prostate (p=0.02). CONCLUSION: Pumpkin seed oil alone or combined with Phytosterol-F can block the T-P-induced increases in prostatic weight-to-body weight ratio and protein synthesis.

Animals↗
PubMed2005

Inhibitory effect of 5-hydroxytryptamine on hyperphagia in mice with genetic overexpression of neuropeptide Y.

The present study examined the effect of 5-hydroxytraptamine (5-HT) on the feeding behavior of transgenic mice with neuropeptide Y (NPY) overexpression. Solution of 5-HT (1, 2.5 or 5 mg/kg) was administered intraperitoneally into (1) NPY-overexpressing mice, and (2) wild-type mice with 2-deoxy-d-glucose (2-DG) induced hyperphagia. The NPY-overexpressing mice were further divided into five groups: (1) control mice, (2) mice treated with 5-HT (5 mg/kg), (3) mice treated with 5-HT (5 mg/kg) and ketanserin (0.5 or 1 mg/kg), a 5-HT2A receptor antagonist, (4) mice treated with insulin (1 IU/kg), and (5) mice treated with insulin (1 IU/kg) and 5-HT (5 mg/kg). Food intake and plasma glucose levels were measured. The results showed that 5-HT reduced hyperphagia in both NPY-overexpressing mice and 2-DG-treated mice in dose-dependent manner. Hyperglycemia was induced by 5-HT administration. Ketanserin antagonized the 5-HT induced hypophagia and hyperglycemia. Insulin, on the other hand, prevented 5-HT induced hyperglycemia but not the hypophagic effect. In conclusion, 5-HT reduces hyperphagia in the NPY-overexpressing rat through action on 5-HT2A receptors and this hypophagic effect of 5-HT does not depend on the hyperglycemia.

Animals↗
PubMed2005

The role of sorbitol pathway and treatment effect of aldose reductase inhibitor ONO2235 in the up-regulation of cardiac M2-muscarinic receptors in streptozotocin-induced diabetic rats.

This study investigated the role of the sorbitol pathway on the genetic up-regulation of the cardiac M(2) muscarinic receptor (M(2)-mAChR) in streptozotocin (STZ)-induced diabetic rats. Three-month-old male Wistar rats were divided into five groups: (1) normal controls; (2) rats rendered diabetic by streptozotocin; (3) rats fed with glucose; (4) rats injected with sorbitol; and (5) diabetic rats treated with ONO-2235, an aldose reductase inhibitor. The M(2) muscarinic receptor (M(2)-mAChR) protein and mRNA densities of the heart tissue were measured by Western immunoblotting and Northern blotting, respectively. The densities of M(2)-mAChR protein and mRNA in the heart were significantly increased in diabetic rats, and rats given either glucose or sorbitol. When diabetic rats were treated with ONO-2235, the increases in heart M(2)-mAChR protein and mRNA were significantly reduced. The findings suggest that hyperglycemia and the sorbitol pathway are involved in the pathogenesis of diabetic heart disease in STZ-induced diabetic rats. Aldose reductase inhibitors may be useful in the treatment and prevention of cardiac complication in diabetes.

Aldehyde Reductase↗
PubMed2005

Changes in bladder nerve-growth factor and p75 genetic expression in streptozotocin-induced diabetic rats.

OBJECTIVE: To assess changes associated with diabetes in urinary bladder nerve-growth factor (NGF) and NGF receptor p75NTR expression using a streptozotocin (STZ)-induced diabetic rat model. MATERIALS AND METHODS: Male Wistar rats (32) were divided into four equal groups: group I, vehicle-treated normal rats; group II, vehicle-treated 9-week STZ-diabetic rats; group III, insulin-treated 9-week STZ-diabetic rats; group IV, phlorizin-treated 9-week STZ-diabetic rats. Bladder NGF levels were measured by enzyme-linked immunosorbent assay. Expressions of the mRNAs that encoded NGF and NGF receptor p75NTR in the rat bladder were evaluated using reverse transcription-polymerase chain reaction. RESULTS: The mean (SEM) NGF level in the STZ-diabetic rat bladder was significantly lower than in the control group, at 56.56 (8.28) and 84.33 (11.05) pg/microg protein, respectively (P < 0.01). The mRNA expressions of bladder NGF and p75NTR in the diabetic rats were significantly lower than in the control group (P < 0.05 and <0.001, respectively). Treatment with either insulin or phlorizin restored the normal blood sugar level; moreover, the bladder NGF levels and the expressions of both NGF and p75NTR mRNAs were normal. CONCLUSION: The decrease in the genetic expression of NGF and p75NTR might be responsible for the pathogenesis of diabetic cystopathy while hyperglycaemia is part of the cause of these changes.

Animals↗
PubMed2005

Experience with primary urethral carcinoma from the blackfoot disease-endemic area of South Taiwan: increased frequency of bulbomembranous adenocarcinoma?

OBJECTIVES: To describe and compare primary urethral carcinomas in South Taiwan with those in the USA and to explore the influence of chronic arsenic exposure. METHODS: From 1988 to 2001, there were 21 pathologically proven primary urethral carcinomas diagnosed and treated at our hospital (14 males, 7 females). Seven of 14 male patients were chronically exposed to arsenic in drinking water for an average of 23 years. We compared our cases to three studies in the USA (80 males, 179 females), and analyzed the influence of chronic arsenic exposure by onset age, histology, staging, and outcome. RESULTS: Male patients with localized tumors had better survival compared to those with advanced tumors (p = 0.0045 in males, p = 0.07 in females). In comparison to the three studies in the USA, there was an unusual higher frequency of bulbomembranous adenocarcinoma at our center (43 vs. 18%, 2 and 0%, respectively, p < 0.0001), particularly among those with chronic arsenic exposure (73 vs. 14%, p = 0.031). CONCLUSIONS: In South Taiwan, there was a high frequency of bulbomembranous urethral adenocarcinoma, which might be associated with chronic arsenic exposure. Although the implications of such an observation are minimal owing to its rarity, it is worth exploring.

Adenocarcinoma↗
PubMed2004

Inhibitory effect of buflomedil on prostate alpha1A adrenoceptor in the Wistar rat.

The inhibitory effect of buflomedil on alpha1A-adrenoceptor (AR) in the prostate of Wistar rat was investigated in this study. Normotensive and spontaneous hypertensive rats were orally fed with buflomedil (150 mg/kg). The drug effects on blood pressure and heart rate were monitored by photoelectric volume oscillometric method. Prostate tissue strips from normotensive rats were contracted in vitro in organ bath by phenylephrine (10(-8) to 10(-2)M). The inhibitory effects of buflomedil (10(-9) to 10(-7)M) on the phenylephrine-induced contractions were measured. Radioligand binding displacement study by buflomedil was performed on rat prostate alpha1A-adrenoceptor (AR) and spleen alpha1B-AR. Furthermore the effects of buflomedil and WB-4101 on phenylephrine (10 microM) activated uptake of 2-[14C]-deoxy-d-glucose (2-DG) into C2C12 cells were evaluated. The results showed that buflomedil feeding did not alter the systolic blood pressure of either spontaneous hypertensive rats or normal rats. Dose-inhibition curves of phenylephrine-induced prostate contraction demonstrated a higher potency of buflomedil than tamsulosin. Buflomedil displaced [3H]prazosin binding in a concentration-dependent manner both in rat prostate alpha1A-AR and spleen alpha1B-AR. The ratio of affinity to alpha1A-AR and alpha1B-AR for buflomedil was 4.06/6.84, indicating selectivity on alpha1A-AR over alpha1B-AR. Activation of C2C12 cell alpha1A-AR by phenylephrine increased the glucose uptake to 116%. Both buflomedil and WB-4101 inhibited the uptake in a concentration-dependent manner. In conclusion, the findings showed that buflomedil has preferential alpha1A-AR antagonistic effect to inhibit prostate contraction without significantly affecting the blood pressure.

Adrenergic alpha-Agonists↗
PubMed2003

Bilateral emphysematous pyelonephritis combined with subcapsular hematoma and disseminated necrotizing fasciitis.

Emphysematous pyelonephritis (EPN) is a rapidly progressive and potentially life-threatening necrotizing infection of the renal parenchyma characterized by the presence of gas. Bilateral EPN is a rare disease process with a high mortality rate. Bleeding associated with EPN is an extremely rare complication. Necrotizing fasciitis is a rare but serous condition with a poor prognosis. Herein we present a rare case of bilateral EPN combined with subcapsular hematomas which progressed to the development of disseminated necrotizing fasciitis.

Emphysema↗
PubMed2003

Alteration of alpha(1A)-adrenoceptor gene expression in the prostate of streptozotocin-induced diabetic rats.

Diabetes-associated alterations in prostate alpha(1A)-adrenoceptor (alpha(1A)-AR) gene expression were studied using a streptozotocin (STZ) induced diabetic rat model. Male Wistar rats were divided into four groups: group I animals were vehicle-treated normal rats; group II consisted of vehicle-treated, STZ-diabetic rats; group III represented insulin-treated, STZ-diabetic rats (0.5 IU/kg three times daily for 4 days), and group IV animals were phlorizin-treated, STZ-diabetic rats (1 mg/kg three times daily for 4 days). The expression of mRNA that encoded protein of alpha(1A)-AR in the rat prostate was studied using reverse transcription combined with polymerase chain reaction. The alpha(1A)-AR protein expression in the prostate was studied by Western blotting analysis with a polyclonal antiserum. A 2.51 +/- 0.21-fold increase in the mRNA level of alpha(1A)-AR was observed in the prostate of diabetic rats (n = 8, p < 0.05). Similarly, there was a 2.23 +/- 0.10-fold increase in the alpha(1A)-AR protein level (n = 8, p < 0.05). Both insulin and phlorizin treatments restored the normal levels of mRNA and protein expression. In conclusion, the gene expression of alpha(1A)-AR is increased in the prostate of diabetic rats. Hyperglycemia plays a major role in this alteration.

Animals↗
PubMed2003

An alternative method of tension-free vaginal tape implantation for the treatment of female urinary incontinence.

AIM: To present an alternative technique of implanting the tension-free vaginal tape (TVT) to minimize the risk of bladder perforation or major pelvic injuries. PATIENTS AND METHODS: Sixteen female patients with stress urinary incontinence were operated on. The procedure was performed under epidural/spinal anesthesia. A vaginal inverted U incision was made. Dissection was performed alongside the urethra bilaterally and the index finger bluntly dissected into the Retzius space after perforation of the endopelvic fascia. The TVT needle was passed through the lower abdominal wall guided by finger. The rest of the procedure was then finished up as originally described. RESULTS: All patients underwent the operation smoothly without any bladder perforation or major pelvic injury. The mean operative time was 49 (range 32-87) min, and no patient had blood loss >100 ml. All patients could void satisfactorily within 2 weeks. Postoperatively, 94% of the patients (15/16) reported complete dryness, and 6% (1/16) significantly improved. At follow-up after 6 months, the dry rate was 87% (14/16) and the improvement rate 13% (2/16). The 24-hour pad test was significantly improved: preoperatively 112 +/- 43 g; postoperatively 8.5 +/- 4 g (p < 0.001). The maximum flow rate was not significantly reduced: preoperatively 27.1 +/- 8.9 ml/s, postoperatively 24.6 +/- 6.4 ml/s (p > 0.05). No patient had residual urine >50 ml. CONCLUSIONS: The reported technique offers an alternative way for TVT implantation. The intent is to minimize the risk of major pelvic injury and bladder perforation without compromising the surgical outcomes. Such benefit may outweigh the additional trouble of periurethral dissection.

Adult↗
PubMed2003

Prognostic values of p53 and HER-2/neu coexpression in invasive bladder cancer in Taiwan.

OBJECTIVES: To explore the clinical significance of p53 and HER-2/neu coexpression by immunohistochemistry in patients with invasive bladder cancer in Taiwan. METHODS: Paraffin-embedded tumor blocks were obtained from 67 patients with invasive bladder cancer subjected to radical cystectomy, bilateral lymph node dissection, and urinary diversion with or without systemic chemotherapy. Two observers (N.H.C. and T.S.T.), blinded to clinical outcome, reviewed the immunohistochemical staining for p53 (PAb1801) and HER-2/neu (Ab-17). The results were analyzed for progression-free survival and patient survival. RESULTS: Positive staining for p53 and HER-2/neu was found in 30 (44.8%) and 39 (58.2%) patients. In contrast to HER-2/neu, p53 expression was significantly associated with tumor grade and pathologic stage (p = 0.040 and 0.004, respectively), and tended to be related to the nodal status (p = 0.080). Most importantly, coexpression of p53 and HER-2/neu significantly correlated with nodal metastases (p = 0.020). Univariate and multivariate analysis revealed p53 and nodal status as two independent prognostic factors. Additionally, patients with p53 and HER-2/neu coexpression had the shortest time to relapse and overall survival, irrespective of whether adjuvant chemotherapy was given or not (p = 0.005 and 0.030). CONCLUSIONS: In invasive bladder cancer, p53 was an important prognostic factor since its expression correlated with tumor grade and stage, even nodal status, whereas HER-2/neu did not show prognostic significance. Tumors with p53 and HER-2/neu coexpression were associated with nodal metastases, probably resulting in decreased progression-free survival. Although some basic studies provide some important supports, studies including larger patient cohorts would still be required to prove the hypothesis that p53 and HER-2/neu-coexpressing tumors have a worse prognosis and are more resistant to a cisplatin-based multidrug regimen.

Adult↗
PubMed2002

Effects of Ba-Wei-Die-Huang-Wan on the cholinergic function and protein expression of M2 muscarinic receptor of the urinary bladder in diabetic rats.

The study investigated the effect of a traditional Chinese herbal preparation 'Ba-Wei-Die-Huang-Wan' on the cholinergic function of the urinary bladder in diabetic rats, as well as its influence on the protein expression of muscarinic M(2) receptors. Wistar rats were divided into three groups: (1) control rats; (2) 2-week streptozotocin-induced diabetic rats; and (3) diabetic rats treated with Ba-Wei-Die-Huang-Wan 26 mg/kg thrice daily for 3 days. A dose-response study was performed for bladder muscle strip contractile response to a muscarinic agonist, arecaidine propargyl ester (APE). The amount of M(2) receptor protein in the bladder was measured by Western immunoblotting using monoclonal antibodies. The bladder contractile response to APE was significantly increased in the diabetic rats compared to the control. The M(2) receptor protein density was also significantly higher by 106% (P < 0.01, n = 8) in diabetes. Ba-Wei-Die-Huang-Wan treatment significantly lowered the plasma glucose level of the diabetic rats. The increases in contractile response to APE as well as the M(2) receptor protein density were partially reversed by the treatment. In conclusion, there was an over-expression of M(2) receptor resulting in hyper-contractility in the bladder of diabetic rats. Ba-Wei-Die-Huang-Wan significantly alleviated the alterations.

Animals↗
PubMed2002

Role of sorbitol in the up-regulation of urinary bladder M(2) muscarinic receptors in streptozotocin-induced diabetic rats.

This study investigated the role of sorbitol, a metabolic product of glucose, in the pathogenesis of rat diabetic cystopathy. Three-month-old male Wistar rats were divided into four groups: 1) normal controls; 2) rats rendered diabetic by streptozotocin; 3) rats fed with glucose; and 4) rats injected with sorbitol. The M(2) muscarinic receptor (M(2)-mAChR) protein and mRNA densities of the bladder tissue were measured by Western immunoblot and Northern blot, respectively. The streptozotocin-induced diabetic rats were then treated with ONO-2235, an aldose reductase inhibitor. The bladder M(2)-mAChR protein and mRNA were compared between the treated and untreated diabetic rats. The densities of M(2)-mAChR protein and mRNA in the bladder tissue were significantly increased in diabetic rats, and rats given either glucose or sorbitol (increases in receptor protein: 27.3 +/- 3.3, 19.8 +/- 2.3, and 18.0 +/- 2.1%; increases in mRNA: 39.6 +/- 3.7, 33.1 +/- 2.9, and 20.2 +/- 2.2%, respectively). When diabetic rats were treated with ONO-2235, the increases in bladder M(2)-mAChR protein and mRNA were significantly alleviated. The findings suggest that sorbitol plays a role in the pathogenesis of diabetic cystopathy in rats rendered diabetic by streptozotocin. Aldose reductase inhibitors may be useful in the treatment and prevention of diabetic cystopathy.

Aldehyde Reductase↗