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S F Matin

Publications and source records attributed to S F Matin.

8 recordsLinked to original sources
PubMed2001

Impaired alpha-interferon signaling in transitional cell carcinoma: lack of p48 expression in 5637 cells.

The limited success of IFN-alpha therapy for clinical treatment of transitional cell carcinoma (TCC) has prompted us to investigate the responsiveness of TCC lines to IFN-alpha. The response to IFN-alpha in terms of 561 gene induction, an IFN-stimulated response element-containing IFN-alpha/beta-inducible gene, and IFN-stimulated gene factor 3 (ISGF3) formation was normal in primary human urothelial cells. We tested the antiproliferative effects of IFN-alpha in three TCC lines as a measure of IFN-alpha responsiveness, and variable patterns of growth inhibition were observed in three TCC lines. More than 90% growth inhibition was noted in TCCSUP cells, whereas only 40% and 10% inhibition by IFN-alpha was observed in 5637 and HT1197 cells, respectively. IFN-alpha treatment formed extremely low levels of ISGF3 in electrophoretic mobility shift assays in these later two relatively insensitive cells. In addition, expression of the 561 gene was significantly reduced in these two TCC lines by Northern blots. We have further identified a low expression level of Tyk2 in HT1197 cells compared with two other TCCs. This suggests that an extremely low ISGF3 level after IFN-alpha treatment may be due to low Tyk2 expression or other unidentified defects. In 5637 cells, p48 protein expression was undetectable. This undetectable p48 expression is not due to a deletion in the coding region because the correct size protein is detected following IFN-gamma treatment. Consequently, the ISGF3 complex formation and 561 gene induction were restored by IFN-gamma pretreatment plus IFN-alpha treatment. Introduction of p48 expressing plasmid into 5637 cells was sufficient to form the ISGF3 complex by IFN-alpha treatment, suggesting the defect lies in the expression of p48 protein in 5637 cells. Detailed mechanistic understanding of the action of IFNs in bladder cancer cell lines may explain the abrogated therapeutic response of IFN-alpha in the clinical treatment of TCCs.

Carcinoma, Transitional Cell↗
PubMed2001

Extracorporeal shock-wave lithotripsy: a comparative study of electrohydraulic and electromagnetic units.

PURPOSE: We determined the results of shock wave lithotripsy with a newer electromagnetic lithotriptor and compared them with those in a contemporary series of cases managed by an electrohydraulic lithotriptor using identical treatment and followup criteria at a single center. MATERIALS AND METHODS: Between 1995 and 1999, 356 patients (375 renal units, 483 upper urinary tract stones) meeting study inclusion criteria were treated with an MFL 5000 electrohydraulic shock wave lithotripsy unit (Dornier Medical Systems, Inc., Marietta, Georgia). From 1999 to 2000, 173 patients (175 renal units; 218 upper urinary tract stones) meeting identical study inclusion criteria were treated using an electromagnetic Modulith SLX shock wave lithotripsy unit (Karl Storz Lithotripsy, Atlanta, Georgia). In each group stone-free results were determined by plain abdominal x-ray and renal ultrasound 1 month after lithotripsy and efficiency quotients were developed. Baseline patient and stone characteristics were compared by the Wilcoxon rank sum and Fisher exact tests. All variables significant at p <0.05 were included in subsequent outcome analysis using multivariate logistic regression. RESULTS: Baseline characteristics were equivalent, including patient age, gender, stone number and location, although patients treated with the electrohydraulic unit had a significantly larger median stone burden (103 versus 71 mm.2, p = 0.015). Multivariate regression analysis demonstrated a higher stone-free rate in the electrohydraulic group (77% versus 67%, p = 0.01) but also a higher rate of total adjunctive measures (56% versus 47%, p = 0.04). Consequently the efficiency quotients were comparable for the electrohydraulic and electromagnetic lithotripsy units (0.45 and 0.42, respectively, p = 0.43). CONCLUSIONS: Electrohydraulic lithotripsy resulted in a higher stone-free rate at 1 month, although it was associated with a higher rate of auxiliary measures. Ultimately the efficiency quotients were equivalent, implying that these 2 contemporary energy sources are acceptable. According to single center treatment and followup criteria they are equally efficacious.

Adolescent↗
PubMed2001

Laparoscopic ultrasonography.

The use of laparoscopic ultrasonography (LUS) allows visualization of tissues beyond the two-dimensional laparoscopic picture, enhancing the amount and quality of information available to the surgeon. Linear-array transducers with frequencies of 7.5 to 10 MHz are typically used for LUS, employing B-mode scanning and color Doppler capability on probes with articulating tips. In general surgery, LUS has become a common adjunct to the intraoperative staging of upper gastrointestinal malignancy to determine resectability, avoiding unnecessary laparotomy. In urology, LUS appears to be a promising adjunct for four current procedures: difficult pelvic lymphocele marsupialization, renal cyst decortication, nephrolithotomy and other renal stone surgery, and cryotherapy of renal masses. The role of LUS during varicocelectomy is limited, and enthusiasm for this procedure is waning. Laparoscopic ultrasonography is a critical adjunct to renal cryoablation, a developmental procedure that currently lacks long-term data but is promising as therapy for small, incidentally detected renal masses. It appears that as laparoscopic urologic procedures continue to expand, so will the application of this promising operative imaging modality.

Diagnostic Techniques, Urological↗
PubMed2001

Renal dysfunction associated with staged bilateral partial nephrectomy: the importance of operative positioning.

PURPOSE: Remnant kidneys may be susceptible to injury during positioning for a contralateral flank incision. We document renal dysfunction in a remnant kidney after staged partial nephrectomies. MATERIALS AND METHODS: We review a case of renal dysfunction associated with staged bilateral partial nephrectomy. Pertinent data and radiographic findings are presented. RESULTS: A man with multiple bilateral solid enhancing renal masses underwent left partial nephrectomy, resulting in sparing of 50% of the renal parenchyma. Postoperatively nuclear renography showed excellent flow and 33% function on that side. Right partial nephrectomy was then performed via the standard flank approach through the bed of the 11th rib, sparing 50% of the renal parenchyma. Cold ischemia time was 40 minutes. Serum creatinine increased to 4.9 mg./dl. within 48 hours. Nuclear renography immediately postoperatively showed poor flow and 13% function in the left kidney. CONCLUSIONS: Limited published data imply detrimental hemodynamic and myocutaneous consequences due to use of the kidney rest. Table flexion with elevation of the kidney rest may also cause ischemic damage in a previously operated contralateral kidney. Careful positioning is critical for preventing undue injury to the remnant kidney and in such cases elevation of the kidney rest should be avoided. Alternatively stage 2 may be approached via an anterior incision.

Humans↗
PubMed2001

Renal outcome 25 years after donor nephrectomy.

PURPOSE: The extended outcome after kidney donation has been a particular concern ever since the recognition of hyperfiltration injury. Few published reports have examined donor renal outcome after 20 years or greater. Kidney transplantation has been performed at the Cleveland Clinic Foundation since 1963, at which there is extensive experience with live donor transplantation. We assess the impact of donor nephrectomy on renal function, urinary protein excretion and development of hypertension postoperatively to examine whether renal deterioration occurs with followup after 20 years or greater. MATERIALS AND METHODS: From 1963 to 1975, 180 live donor nephrectomies were performed at the Cleveland Clinic. We attempted to contact all patients to request participation in our study. Those 70 patients who agreed to participate in the study were mailed a package containing a 24-hour urine container (for assessment of creatinine, and total protein and albumin), a vial for blood collection (for assessment of serum creatinine) and a medical questionnaire. All specimens were returned to and processed by the Cleveland Clinic medical laboratories. Blood pressure was taken and recorded by a local physician. A 24-hour creatinine clearance and the Cockcroft-Gault formula were used to estimate renal function, and values were compared with an age adjusted glomerular filtration rate for a solitary kidney. RESULTS: Mean patient followup was 25 years. The 24-hour urinary creatinine clearance decreased to 72% of the value before donation. For the entire study cohort serum creatinine and systolic blood pressure after donation were significantly increased compared with values before, although still in the normal range. The overall incidence of hypertension was comparable to that expected in the age matched general population. There was no gender or age difference (younger or older than 50 years) for 24-hour urinary creatinine clearance, or change in serum creatinine before or after donation. Urinary protein and albumin excretion after donation was significantly higher in males compared with females. There were 13 (19%) subjects who had a 24-hour urinary protein excretion that was greater than 0.15 gm./24 hours, 5 (7%) of whom had greater than 0.8. No gender difference was noted in blood pressure, and there were no significant changes in diastolic pressure based on gender or age. CONCLUSIONS: Overall, renal function is well preserved with a mean followup of 25 years after donor nephrectomy. Males had significantly higher protein and albumin excretion than females but no other clinically significant differences in renal function, blood pressure or proteinuria were noted between them or at age of donation. Proteinuria increases with marginal significance but appears to be of no clinical consequence in most patients. Patients with mild or borderline proteinuria before donation may represent a subgroup at particular risk for the development of significant proteinuria 20 years or greater after donation. The overall incidence of proteinuria in our study is in the range of previously reported values after donor nephrectomy.

Adult↗
PubMed2000

Laparoscopic marsupialization of the difficult lymphocele using internalized peritoneal dialysis catheter.

PURPOSE: Definitive treatment of the recurrent or anatomically difficult lymphocele without a common wall between the lymphocele and peritoneal cavities requires open surgery. We present a novel technique of laparoscopic marsupialization of such lymphoceles with placement of a cable of 2 internalized peritoneal dialysis catheters for maintaining permanent lymphoperitoneal drainage. MATERIALS AND METHODS: Two patients with a symptomatic, post-renal transplant pelvic lymphocele underwent the procedure. Laparoscopic marsupialization was performed with ultrasound guidance and in each case a cable of 2 internalized peritoneal dialysis catheters was anchored through the limited peritoneal window to maintain lymphoperitoneal drainage. RESULTS: Both procedures were successful. During a followup of 20 and 21 months, respectively, no recurrence or infectious complications were noted in these immunocompromised patients. CONCLUSIONS: Laparoscopic marsupialization with internalization of peritoneal dialysis catheters is a feasible, alternative measure available for select cases with a difficult or recurrent lymphocele.

Catheterization↗
PubMed2000

Metabolic risk factors in patients with ureteropelvic junction obstruction and renal calculi.

PURPOSE: We performed a prospective study to determine the incidence and spectrum of metabolic abnormalities predisposing to stone formation in patients with ureteropelvic junction obstruction and renal calculi. MATERIALS AND METHODS: A total of 47 consecutive patients with congenital ureteropelvic junction obstruction underwent metabolic evaluation of stone risk factors. Of these patients 21 had associated stones (study group), while 26 did not (control group). Logistical regression, Wilcoxon rank sum and Fisher's exact tests were performed to determine whether there was a significant difference between these groups in regard to the presence of metabolic risk factors. RESULTS: Demographically and symptomatically the 2 groups were equivalent except that the study patients were older. The 24-hour urinary excretion of calcium was significantly higher in study than in the control patients (p = 0.007). While the incidence of hypercalciuria and hyperuricosuria was also higher in the study population, these differences were not significant (p = 0.08 and 0.07, respectively). CONCLUSIONS: Metabolic abnormalities predisposing to stone formation are present more frequently in patients with ureteropelvic junction obstruction who have associated stones compared to those who do not. As such, urinary stasis alone does not explain stone formation in these cases. Rather, the local physiological environment of urine likely has a predisposing role. In addition to restoring unobstructed urinary flow, consideration should be given to metabolic evaluation and prophylactic treatment for affected patients.

Adolescent↗