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Allen W Chiu

Publications and source records attributed to Allen W Chiu.

At least 19 recordsLinked to original sources
PubMed2006

Survival analysis in patients with upper urinary tract transitional cell carcinoma: a comparison between open and hand-assisted laparoscopic nephroureterectomy.

OBJECTIVE: To evaluate the stage- and grade-specific survival rate in patients with upper urinary tract (UUT) transitional cell carcinoma (TCC) after open (ONU) or hand-assisted laparoscopic nephroureterectomy (LNU) with bladder-cuff excision. PATIENTS AND METHODS: From January 1998 to April 2005, 143 patients with UUT-TCC were treated with either ONU or LNU and enrolled in the study. The peri-operative data were collected by retrospective chart review. The recurrence, metastasis and survival rate were calculated. RESULTS: The 5-year disease-specific survival of patients with pT1 disease was 88.1% after ONU and 92.0% after LNU (P = 0.745); the respective values for patients with pT2 were 11/17 and 12/15 (P = 0.874), and for pT3 were six/11 and 12/15 (P = 0.476). The incidence of bladder recurrence within 2 years after surgery was 24.7% for ONU and 19.7% for LNU (P = 0.475). CONCLUSION: The results were similar after ONU or LNU with bladder-cuff excision; bladder-cuff excision using a hand-assisted device is effective and serves as a treatment option for patients with UUT-TCC.

Aged↗
PubMed2005

Enhanced transformation and chemosensitivity of NIH3T3 cells transduced with hepatoma up-regulated protein.

Hepatoma up-regulated protein (HURP) is a recently identified novel cell-cycle-regulated gene. The HURP gene is overexpressed in human hepatocellular carcinoma and transitional cell carcinoma. The cellular function of HURP is not fully understood. In this study, the NIH3T3 cells transduced with the exogenous HURP gene manifested the general characteristics of tumor cells, which had higher growth rate in low-serum media and advanced ability of colony formation on agarose-based plates. Transduced HURP was capable of specifically enhancing the chemosensitivity of deoxycytosine analogs, such as gemcitabine, ARA-C, and 5-AZA-CdR, but neither had an effect on the response of DNA intercalating agents, such as cisplatin, carboplatin, and doxorubicin, nor on the response of microtubule stabilizers, such as paclitaxel, docetaxel, and vinblastine. These results indicate that the HURP gene might be a potential oncogenic gene and capable of enhancing the chemosensitivity of deoxycytosine analogs in NIH3T3 cells.

Animals↗
PubMed2005

Comprehensive study of bladder neck contracture after transurethral resection of prostate.

OBJECTIVES: To test the validity of transurethral resection of the prostate (TURP) plus transurethral incision (TUI) of bladder neck as an alternative to TUI of the prostate, a nonrandomized and retrospective study was done to review comprehensively the incidence of, severity of, and risk factors for bladder neck contracture (BNC) in patients with benign prostatic hyperplasia who underwent transurethral surgery. METHODS: The evaluation parameters included age, prostate-specific antigen level, urinalysis and uroflowmetry findings, voided volume, presence of vesical stones and urinary retention, surgical type, adenoma weight, and perioperative morbidities. RESULTS: Of the 1470 patients studied, 1135 (77.2%) were eligible for analysis. At a mean follow-up of 37.9 months, 110 patients (9.7%) had developed BNC. The adenoma weight, blood transfusion, and postoperative maximal and mean flow rate in patients with BNC were significantly less than in patients without BNC. The incidence of BNC in the TURP group was greater than that in the TURP plus TUI group (12.3% versus 6%, P = 0.000). BNC was completely prevented using TURP plus TUI if the adenoma weight was greater than 30 g. However, in the TURP group, 4% of patients developed BNC even with an adenoma weight greater than 50 g. Multivariate analyses showed that adenoma weight and surgical type were significant risk factors for BNC. Patients with associated vesical stones were less prone to develop BNC. CONCLUSIONS: TURP plus TUI provides a pathologic diagnosis, and with minimal morbidity, it can be an alternative to TUI of the prostate in selected patients. Personal diathesis may play a role in the pathogenesis of BNC.

Aged↗
PubMed2005

Clinical experience of laparoscopic-assisted radical cystectomy with continent ileal reservoir.

INTRODUCTION: Laparoscopic-assisted radical cystectomy with continent ileal reservoir reconstruction is a challenging procedure. We report our experience learned from a hand-assisted laparoscopic technique in our transition to a pure laparoscopic approach. MATERIALS AND METHODS: Eighteen consecutive patients underwent laparoscopic-assisted radical cystectomy with continent ileal reservoir. Hand-assisted laparoscopy was used for the first 11 patients and pure laparoscopy was performed for the subsequent 7 patients in radical cystectomy. Continent ileal reservoir reconstruction was performed extracorporeally via the hand port wound or trocar extension wound. Surgical outcome was analyzed in a retrospective review of the medical records. RESULTS: In the hand-assisted and pure laparoscopic groups, the mean operative time for cystectomy was 2.5 and 2.3 h, for continent ileal reservoir reconstruction it was 4.0 and 3.7 h, and for bilateral lymph node dissection it was 0.8 and 0.6 h, respectively. Mean intraoperative blood loss was 286 ml for the hand-assisted and 179 ml for the pure laparoscopic group. There were no major intraoperative complications nor need for conversion in any of the procedures. Bowel movement was regained in a mean of 3 days and the mean length of postoperative hospital stay was 7 days. CONCLUSIONS: The hand-assisted laparoscopic experience of radical cystectomy learned from the initial 11 patients effectively helped us in the transition to a pure laparoscopic approach. A comparable surgical outcome was found in both groups of patients.

Aged↗
PubMed2005

Is Fournier's gangrene severity index useful for predicting outcome of Fournier's gangrene?

OBJECTIVES: Fournier's gangrene (FG) is a rare but life-threatening disease. Although antibiotics and aggressive debridement have been broadly accepted as the standard treatment, the mortality rate remains high. We conducted a retrospective study to analyze the outcome and identify the risk factors and prognostic indicators. METHODS: We retrospectively reviewed the medical records of 25 patients diagnosed with FG between July 1993 and August 2003. Data collected included age, predisposing factors, treatment modalities, length of hospital stay, surgical debridement times, and outcome. The FG severity index was used to predict outcome. Univariate analysis of the different prognostic factors was performed using t test and Fisher's exact probability test. RESULTS: All patients were male, 60% were diabetic, and the mean age was 55.8 years. The mean hospital stay was 20 days and the mortality rate was 32%. The mean age of 53.8+/-18.3 (SD) years in the survival group (n=17) was significantly lower than the 59.9+/-10.2 years (n=8) of the non-survival group (p<0.05). Non-survival group patients had lower serum hematocrit (mean 28.9, p=0.019) and albumin (mean 1.93, p=0.024) levels. In our series, the mean FG severity index for survivors was 4.41+/-2.45 (range 2-9) compared to 12.75+/-2.82 (range 9-18) for those who died (t test, p<0.0001). CONCLUSION: The survival rate of younger patients with FG was higher. We agree that a FG severity index cutoff value of 9 is an excellent predictor of outcome.

Adult↗
PubMed2005

Perioperative hypertensive crisis in clinically silent pheochromocytomas: report of four cases.

Improvements in imaging have resulted in an increase in incidentally discovered adrenal tumors. The adrenal incidentalomas have been identified in at least 2%-3% of patients receiving abdominal computed tomography (CT), and pheochromocytomas are reported to occur in about 5.1%-23.0% of those patients. Only a few case reports of clinically silent pheochromocytomas have been published in the English literature. Herein we present 4 cases of pheochromocytomas as unforeseen adrenal masses on abdominal images. The characteristics of these tumors were that they (1) were noted to have no particular symptoms, (2) were confirmed biochemically and pathologically with immunophenotypic staining, (3) were benign in nature, and (4) produced apparent blood-pressure fluctuations during the operation. Three of these patients underwent a hypertensive crisis during surgery, and antihypertensives were applied transiently for blood pressure control. Two cases suffered from dramatic hypotension after the tumor had been excised, and intravenous fluid expanders and ephedrine were necessary to maintain adequate blood pressure. The above changes in blood pressure had no correlations with the size of the tumors. Although these tumors were clinically silent, they indeed were biologically active. Surgical resection of these tumors was indicated, and the risk of complications, such as hypertensive or hypotensive crises, may be no less than those of other typical tumors. Thus, such tumors should be managed with great caution.

Adrenal Gland Neoplasms↗
PubMed2004

Enhanced adhesion of monocytes via reverse signaling triggered by decoy receptor 3.

Decoy receptor 3 (DcR3), a newly identified soluble protein belonging to the tumor necrosis factor receptor (TNFR) superfamily, is a receptor for Fas ligand (FasL), LIGHT and TL1A. It has been demonstrated that DcR3 is frequently overexpressed by malignant tumors arising from lung, gastrointestinal tract, neuronal glia and virus-associated leukemia. Recently, we demonstrated that DcR3 is able to modulate the differentiation and activation of dendritic cells (DCs), and that DcR3-treated DCs skew naive T cell differentiation towards a Th2 phenotype. In this study, we further demonstrate that DcR3 is able to induce actin reorganization and enhance the adhesion of monocytes and THP-1 cells by activating multiple signaling molecules, such as protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3K), focal adhesion kinase (FAK) and Src kinases. This provides the first evidence that the soluble DcR3, like other immobilized members of TNFR superfamily, is able to trigger 'reverse signaling' to modulate cell function.

Actins↗
PubMed2004

Laparoscopy-assisted transvaginal total exenteration for locally advanced cervical cancer with bladder invasion after radiotherapy.

When invasive cervical cancer involves the urinary bladder or rectum, exenteration can be curative treatment. However, this operation, particularly by an open approach, carries significant morbidity, both physically and psychologically. Laparoscopic surgery has been documented to be a reasonable alternative to the open counterpart for a variety of pelvic operative procedures, including such advanced procedures as laparoscopy-assisted vaginal hysterectomy, total laparoscopic hysterectomy, and laparoscopy radical hysterectomy. With improving surgical technology and increasing surgical experience, exenteration is a logical extension of current laparoscopic practice. However, it raises skepticism regarding the feasibility and justification for the complicated surgery. We herein describe our experience in a patient undergoing total exenteration assisted by laparoscopic technology for advanced recurrent cervical cancer after extensive radiotherapy. Transperitoneal laparoscopic total exenteration with ureterosigmoidstomy and end-sigmoidostomy was accomplished in 6 hours. The whole specimen was removed en bloc transvaginally. The patient tolerated the procedure well. The only complication was a wound infection 50 days postoperatively that was controlled with debridement and antibiotics. No episodes of pyelonephritis occurred. After 1 year of follow-up, the patient is free of cancer by imaging studies and lives without associated morbidity of this extensive palliative operation except the care of the sigmoid colostomy.

Aged↗
PubMed2004

Altered transcripts expression of matrix metalloproteinases and their tissue inhibitors in tenon capsule of patients with glaucoma.

PURPOSE: To determine the transcripts expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in Tenon capsule of patients with primary glaucoma and non-glaucomatous patients who serve as the control. PATIENTS AND METHODS: Specimens of Tenon capsule were obtained intraoperatively and evaluated with the reverse transcriptase-polymerase chain reaction method. The transcripts levels of MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 relative to that of glyceraldehyde phosphate dehydrogenase were determined. RESULTS: The transcripts levels of MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were not correlated with age in the control group. There were differences in the transcripts expression of MMP-2 (P < 0.001), MMP-9 (P = 0.017), TIMP-1 (P < 0.001), and TIMP-2 (P = 0.001) among the control, primary open angle glaucoma, and primary angle-closure glaucoma groups (Kruscal-Wallis H test). Comparing with the controls, open angle glaucoma had decreased transcripts levels of MMP-2 (P = 0.001) and TIMP-1 (P = 0.006) while angle-closure glaucoma had decreased transcripts levels of MMP-2 (P < 0.001), MMP-9 (P = 0.004), TIMP-1 (P < 0.001), and TIMP-2 (P < 0.001) (Mann-Whitney U tests). CONCLUSION: The transcripts expression of certain MMPs and TIMPs is altered in Tenon capsule of glaucoma patients, which might result from long-term application of topical glaucoma medications.

Adolescent↗
PubMed2004

Pneumomediastinum and subcutaneous emphysema as the manifestation of emphysematous pyelonephritis.

Pneumomediastinum, a collection of mediastinal air, often results from the rupture of intrathoracic structures. A 41-year-old diabetic woman initially presented with signs of pneumomediastinum and nuchal subcutaneous emphysema, but was finally diagnosed with unilateral emphysematous pyelonephritis. Pneumomediastinum as a presentation in retroperitoneal infection has not been reported previously, which prompts us to discuss its etiology and emphasize the importance of physical examination.

Adult↗
PubMed2004

A comparison of the clinical outcome between open and hand-assisted laparoscopic nephroureterectomy for upper urinary tract transitional cell carcinoma.

OBJECTIVE: To report the surgical outcome of retroperitoneoscopic hand-assisted laparoscopic nephroureterectomy (LNU) with bladder cuff excision for upper urinary tract transitional cell carcinoma (TCC), and to compare the outcome with that of the open procedure (ONU). PATIENTS AND METHODS: From January 1998 to January 2003, 145 patients with upper urinary tract TCC were enrolled in the study; 87 had ONU and 58 retroperitoneoscopic hand-assisted LNU. The specimens were reviewed by experienced pathologists to confirm the pathological stage. Operative duration, intraoperative blood loss, bowel recovery, analgesic use, hospital stay and time to convalescence were compared for both groups. The Mann-Whitney U-test and Fisher's exact test were used for statistical analysis. RESULTS The mean follow-up for ONU and LNU was 35.1 and 16.0 months, the mean operative duration 230.2 and 259.1 min (P = 0.006), the mean blood loss 747.3 and 408.9 mL (P < 0.001), the mean duration of Foley catheterization 6.8 and 5.1 days (P < 0.001), and the hospital stay 12.6 and 9.3 days (P < 0.001). The bladder recurrence rate 2 years after surgery was 9.1% for ONU and 8.6% for LNU (P = 0.23); the local recurrence rate during the follow-up was 3.4% and none, respectively (P = 0.35). CONCLUSION: Although LNU took longer than ONU the intraoperative bleeding and hospital stay were better than for ONU. Both procedures have statistically comparable bladder recurrence and local recurrence rates.

Adult↗
PubMed2003

Modulation of macrophage differentiation and activation by decoy receptor 3.

Decoy receptor 3 (DcR3) is a soluble receptor of the tumor necrosis factor receptor superfamily and is readily detected in certain cancer patients. Recently, we demonstrated that DcR3.Fc-treated dendritic cells skew T cell responses to a T helper cell type 2 phenotype. In this study, we further asked its ability to modulate CD14+ monocyte differentiation into macrophages induced by macrophage-colony stimulating factor in vitro. We found that DcR3.Fc was able to modulate the expression of several macrophage markers, including CD14, CD16, CD64, and human leukocyte antigen-DR. In contrast, the expression of CD11c, CD36, CD68, and CD206 (mannose receptor) was not affected in the in vitro culture system. Moreover, phagocytic activity toward immune complexes and apoptotic bodies as well as the production of free radicals and proinflammatory cytokines in response to lipopolysaccharide were impaired in DcR3.Fc-treated monocyte-derived macrophages. This suggests that DcR3.Fc might have potent, suppressive effects to down-regulate the host-immune system.

Antigens, CD↗
PubMed2003

Laparoscopic retroperitoneal adrenalectomy: clinical experience with 120 consecutive cases.

OBJECTIVE: Surgical parameters of laparoscopic retroperitoneal adrenalectomy (LRA) for the treatment of benign adrenal tumours were analysed to report the clinical outcomes and technical guidelines for this operation. METHODS: Operative data from 120 consecutive patients who underwent LRA performed by a single surgeon were reviewed. Patients were categorized into one of four stages according to the major technical modifications made during the development of this procedure: needle insufflation, kidney localization, instrument refinement, and the final stage of finger dissection. The surgical parameters of different stages were evaluated, including operation time, operative blood loss, adenoma size, pathology, surgical complications, morbidity, and postoperative recovery. RESULTS: LRA was an evolving technique; operation time and conversion rate decreased gradually as the technique evolved over the years. Operation time was reduced particularly when finger dissection was used to develop the operative working space. Operation time reached a nadir of 80 minutes for patients with left adrenal aldosteronoma after 40 such cases. The overall conversion rate, regardless of the nature of the tumour, was 5%; phaeochromocytoma had the highest conversion rate (43%). A higher conversion rate and longer operation time were noted in patients with Cushing's adenoma or phaeochromocytoma compared to patients with aldosteronoma. CONCLUSION: LRA proved to be a safe and effective treatment for benign adrenal tumours, with few open conversions except for phaeochromocytomas. Finger-assisted dissection for space development was the major factor leading to shortened operation times.

Adrenal Gland Neoplasms↗
PubMed2003

Creation of ureteropelvic junction obstruction and its correction by chemical glue-assisted laparoscopic dismembered pyeloplasty.

PURPOSE: We established a porcine model of ureteropelvic junction (UPJ) obstruction using a laparoscopic technique and assessed the outcome of standard suture-assisted and chemical glue-assisted laparoscopic pyeloplasty. MATERIALS AND METHODS: Female domestic pigs (N = 20) underwent laparoscopic suture-ligature to create UPJ obstruction. One month later, laparoscopic end-to-end anastomosis was performed to correct the obstruction: with standard suturing techniques in 10 animals and with chemical (cyanoacrylate) glue in the other 10. Postoperative ureteral stents were not used. Four weeks postoperatively, intravenous urography was performed to evaluate the patency of the anastomoses. The UPJ was procured by laparotomy to assess the anastomoses and periureteral fibrosis histologically. RESULTS: The UPJ obstruction was created in an average of 15 +/- 6 minutes. There was no early postoperative mortality. Eighteen pigs survived for at least 1 month, and UPJ obstruction developed in 17 (95%). Microscopically, the lumen of the UPJ was partially occluded, measuring an average of 40% +/- 5% of normal. After laparoscopic correction, a patent UPJ was found in seven of nine animals treated with traditional sutures. Among the eight animals with chemically glued anastomoses, none had a patent UPJ, and severe periureteral adhesions and intraluminal fibrosis were noted at the pyeloplasty site. Marked ureteral tortuosity was present in six of the eight pigs receiving glue-assisted pyeloplasty but in none of the animals having suture-assisted pyeloplasty. CONCLUSIONS: Ureteropelvic junction obstruction was established by laparoscopic suture-ligature in a porcine model with a 95% success rate. Chemical glue-assisted anastomosis was inferior to standard laparoscopic sutures for pyeloplasty to correct the obstruction.

Adhesives↗
PubMed2003

Novel intracorporeal vascular knot applier for large vessel ligation in laparoscopic surgery: experience in pigs and preliminary clinical use.

BACKGROUND AND PURPOSE: We designed an intracorporeal knot applier for the ligation of large vessels laparoscopically. The aim of this study was to assess the efficacy and efficiency of this method to control large vessels in pigs. MATERIALS AND METHODS: Six pigs with mean body weight of 28 kg (range 26-30 kg) were enrolled. The standard transperitoneal laparoscopic set-up was established with 15 mm Hg of pneumoperionteum. The right renal hilum was mobilized, and the renal artery and renal vein were separated. A 5-cm segment of inferior vena cava with the right renal vein was skeletonized laparoscopically. Assisted by the novel knot applier, 3-0 silk was used to ligate the renal artery, renal vein, and inferior vena cava. The time required to accomplish these ligatures was recorded. Two intracorporeal knots were applied 5 mm apart, and the vessels were divided between the knots. The knot strength was assessed by measuring the maximal intraluminal pressure required to blast out the knot using gas insufflation. RESULTS: The diameters (mean +/- SD) of the porcine inferior vena cava, renal artery, and renal vein were 11.1 +/- 0.7, 2.9 +/- 0.3, and 4.9 +/- 0.3 mm, respectively. The knotting time was 58.9 +/- 8.6, 57.5 +/- 6.6, and 59.1 +/- 6.3 seconds for these vessels, respectively. No bleeding occurred when the vessels were divided. The average pressure needed to withstand the blast out of the ligature on the inferior vena cava, renal artery, and renal vein was 213.3 +/- 32.7 (range 165-250), 227.5 +/- 14.7 (range 210-250), and 210.8 +/- 21.5 (range 180-240) mm Hg, respectively. CONCLUSIONS: The novel intracorporeal knot applier was easy to use when making a ligature on vessels of different sizes and different wall thicknesses. The time required for making a ligature was short, and the knot was secure enough to withstand a vascular pressure higher than ordinary blood pressure. The laparoscopic device is inexpensive with great potential of being used as a secure vascular ligature provider.

Animals↗
PubMed2002

Modulation of dendritic cell differentiation and maturation by decoy receptor 3.

Decoy receptor 3 (DcR3), a soluble receptor belonging to the TNFR superfamily, is a receptor for both Fas ligand (FasL) and LIGHT. It has been demonstrated that DcR3 is up-regulated in lung and colon cancers, thus promoting tumor growth by neutralizing the cytotoxic effects of FasL and LIGHT. In this study, we found that DcR3.Fc profoundly modulated dendritic cell differentiation and maturation from CD14(+) monocytes, including the up-regulation of CD86/B7.2, and the down-regulation of CD40, CD54/ICAM-1, CD80/B7.1, CD1a, and HLA-DR. Moreover, DcR3-treated dendritic cells suppressed CD4(+) T cell proliferation in an allogeneic MLR and up-regulated IL-4 secretion of CD4(+)CD45RA(+) T cells. This suggests that DcR3.Fc may act not only as a decoy receptor to FasL and LIGHT, but also as an effector molecule to skew T cell response to the Th2 phenotype.

Adjuvants, Immunologic↗
PubMed2002

Potential molecular marker for detecting transitional cell carcinoma.

OBJECTIVES: To assess the expression rate of a cancer-related gene, hepatoma-up-regulated protein (HURP), in the tumor tissue of transitional cell carcinoma (TCC), and to assess the potential suitability of using this gene as a novel molecular marker for detecting TCC in voided urine. METHODS: Total RNA was extracted from 80 TCC tissue samples of the urinary tract. Forty-five of the 80 tumor-adjacent tissue samples were from the same patients and 15 were from control subjects (patients with benign prostatic hyperplasia). The expression levels of HURP mRNA in these specimens were examined using reverse transcriptase-polymerase chain reaction. The HURP mRNA transcripts in voided urine pellets from 14 additional patients were determined using the same method. The messages were normalized to beta-actin mRNA. RESULTS: The detection of HURP expression in the TCC tissue samples had a sensitivity of 88.8% (71 of 80) and a specificity of 100% (15 of 15). Ten of the 45 grossly tumor-adjacent tissue samples expressed HURP mRNA, which may indicate subtle genetic changes in tissue adjacent to tumor. All seven urine specimens from the patients with TCC revealed HURP expression; however, no specimens from patients with nonmalignant diseases did so. CONCLUSIONS: A potential molecular marker for detecting TCC with tissue specimens and voided urine samples has been found. Although the real clinical application of this marker requires additional evaluation, the high sensitivity and specificity of the HURP gene amplification method warrants more investigation in the future.

Biomarkers, Tumor↗