Biomedical subjects

Ofer Nativ

Publications and source records attributed to Ofer Nativ.

27 records · Page 2Linked to original sources

PubMed2004

Complications of laparoscopic urologic surgery.

Laparoscopic techniques performed in the urologic setting have received great attention in the past decade. With the development of improved laparoscopic instrumentation, approaches to gonadal, renal, prostate, and bladder diseases have been successfully performed. A discussion of urologic laparoscopy (UL) with particular attention to potential complications and limitations is presented. Awareness of these evolving technologies remains critical to all surgeons with an interest in laparoscopy.

Clinical Trials as Topic↗

PubMed2003

Molecular analysis of transitional cell carcinoma using cDNA microarray.

The incidence of transitional cell carcinoma (TCC), the fourth most common neoplasm diagnosed in men, is rising. Despite the development of several noninvasive diagnostic tests, none have gained full recognition by the clinicians. Gene expression profiling of tumors can identify new molecular markers for early diagnosis and disease follow-up. It also allows the classification of tumors into subclasses assisting in disease diagnosis and prognosis, as well as in treatment selection. In this paper, we employed expression profiling for molecular analysis of TCC. A TCC-derived cDNA microarray was constructed and hybridized with 19 probes from normal urothelium and TCC tissues. Hierarchical clustering analysis identified all normal urothelium samples to be tightly clustered and separated from the TCC samples, with 29 of the genes significantly induced (t-test, P<10(-5)) in noninvasive TCC compared to normal urothelium. The identified genes are involved in epithelial cells' functions, tumorigenesis or apoptosis, and could become molecular tools for noninvasive TCC diagnosis. Principal components analysis of the noninvasive and invasive TCC expression profiles further revealed sets of genes that are specifically induced in different tumor subsets, thus providing molecular fingerprints that expand the information gained from classical staging and grading.

Adult↗

PubMed2003

Intravesical gemcitabine therapy for superficial transitional cell carcinoma of the bladder: a phase I and pharmacokinetic study.

PURPOSE: To determine maximum-tolerated dose, toxicities, and pharmacokinetics associated with weekly intravesical gemcitabine therapy in patients with superficial bladder cancer. PATIENTS AND METHODS: Fifteen patients with recurrent superficial transitional cell bladder carcinoma who experienced prior intravesical therapy failure were studied. Two to 4 weeks after complete transurethral resection, gemcitabine was administered intravesically, once weekly for 6 consecutive weeks. Dwell time was 2 hours. Pharmacokinetics of gemcitabine and its metabolite, 2'2'-difluorodeoxyuridine (dFdU), were studied in plasma and urine. Cystoscopy was repeated 6 weeks after therapy. RESULTS: Three-patient cohorts were enrolled sequentially at doses of 500, 1,000, and 1,500 mg in 100 mL 0.9% NaCl. Two patients received 2,000 mg in 100 mL. An additional four patients received 2,000 mg in 50 mL. No grade 4 toxicity or clinically relevant myelosuppression was noted. Nine of 13 evaluable patients were recurrence-free at 12 weeks. Low concentrations of gemcitabine (< or = 1 microg/mL) were present transiently in plasma of all patients receiving 2,000 mg in 50 mL. Gemcitabine was undetectable in plasma of other patients. dFdU was undetectable in plasma of patients receiving less than 1,500 mg. At doses > or = 1,500 mg, dFdU concentrations increased until 90 to 120 minutes and then declined little, if any. Plasma dFdU concentrations implied absorption of 0.5% to 5.5% of instilled dose. Between 61% and 100% of the gemcitabine dose was accounted for in voided urine. No dFdU was measured in voided urine. CONCLUSION: Intravesical gemcitabine, at doses up to 2 g/wk, is well tolerated, is associated with minimal systemic absorption, and has promising efficacy in treatment of superficial bladder cancer.

Administration, Intravesical↗

PubMed2003

The value of quantitative 99M technetium dimercaptosuccinic acid renal scintigraphy for predicting postoperative renal insufficiency in patients undergoing nephrectomy.

PURPOSE: Radical nephrectomy is a routine urological practice. However, little is known about the use of dimercapto-succinic acid (DMSA) scan to evaluate compensatory changes after surgery and its ability to identify patient at risk for postoperative chronic renal failure or insufficiency. We predicted remaining kidney function using DMSA scan and serum creatinine. MATERIALS AND METHODS: A total of 42 patients were enrolled in the study. All underwent DMSA scan before surgery and in 38 DMSA scan was done after unilateral nephrectomy. Serum creatinine was determined before and 1 year after surgery. The Student t test was used to determine statistical significance. Spearman rank core analysis was used to evaluate the association of calculated creatinine clearance time after surgery and renal absolute uptake before surgery. We performed 1-way ANOVA comparison of the means to determine the influence of age distribution on kidney hypertrophy and the increase in kidney uptake. RESULTS: Average patient age was 61.5 years. Baseline mean creatinine clearance time was 71.5 ml. per minute, which decreased to 58.6 ml. per minute after nephrectomy (p <0.0001). Before surgery DMSA scan of the remaining kidney demonstrated an absolute uptake of 4.2% higher than that in the resected kidney (13.5% versus 9.35%, p = 0.0008). After nephrectomy the remaining kidney had an average increase of 3.9% of mean absolute uptake (17.7% versus 13.8%, p = 0.0001). Spearman rank core analysis demonstrated an association of higher preoperative absolute uptake in the remaining kidney with postoperatively high creatinine clearance time (r = 0.458, p = 0.003). Furthermore, 75% of patients with postoperative creatinine clearance time less than 40 ml. per minute presented with a preoperative absolute uptake of lower than 11% in the remaining kidney. In contrast, 75% of those with a postoperative creatinine clearance time of higher than 40 ml. per minute had a preoperative absolute uptake of higher than 11%. CONCLUSIONS: A preoperative absolute uptake of lower than 11% in the remaining kidney was a significant risk factor for postoperative chronic renal insufficiency.

Adult↗

PubMed2003

Agents of non-gonococcal urethritis in males attending an Israeli clinic for sexually transmitted diseases.

BACKGROUND: Non-gonococcal urethritis is the most common clinical diagnosis in men seeking care at clinics for sexually transmitted diseases. OBJECTIVE: To identify the pathogens involved in NGU among males attending an Israeli STD clinic. METHODS: During 19 months spanning September 1996 to July 1998 we investigated a cohort of 238 male patients attending the Bnai Zion Medical Center STD clinic with a clinical presentation of urethritis. Intraurethral swab specimens were tested for Neisseria gonorrhea, Ureaplasma urealyticum, Mycoplasma hominis, and Trichomonas vaginalis by culture and for herpes simplex virus by antigen detection. First voiding urine for C. trachomatis was done by polymerase chain reaction. The specific seropositivities of HSV types 1 and 2 were tested by enzyme-linked immunosorbent assay. RESULTS: From among 238 males with dysuria or urethral discharge an etiology for urethritis was found for 71 (29.8%). N. gonorrhea was recovered in only three men (4.2%). In the remaining 68 NGU patients Chlamydia trachomatis (35/68, 51.5%) and U. urealyticum (31/68, 45.6%) were the most common infecting and co-infecting pathogens (P < 0.0001). M. hominis and T. vaginalis were found in 9/68 (13.2%), and 1 patient, respectively. HSV was recovered from the urethra in 7/68 males (10.3%)--3 with HSV-1, 2 with HSV-2, and 2 were seronegative for HSV. None of these males had genital lesions. Although a single etiologic agent was identified in 45/68 infected men (66.2%), co-infection was common: 2 organisms in 15 (22%) and 3 organisms in 8 (11.8%). CONCLUSION: C. trachomatis and U. urealyticum were the most common infecting and co-infecting pathogens in this cohort of men with NGU. Unrecognized genital HSV infections are common in males attending our STD clinic, and symptomatic shedding of HSV occurs without genital lesions. Still, the microbial etiology in this group remains unclear in many patients despite careful microbiologic evaluation.

Adult↗

PubMed2003

[The role of nephron sparing surgery for renal cancer].

AIM: A contemporary review of the indications, techniques and outcome of the nephron sparing surgical approach in the management of solid renal masses. MATERIAL AND METHODS: Pertinent articles were reviewed using the MEDLINE. RESULTS: Nephron sparing surgery is increasingly being used to treat patients with solid renal lesions. The technical success rate of nephron sparing surgery is excellent, and operative morbidity and mortality are low. For renal cell carcinoma, long-term cancer-free survival is comparable to radical nephrectomy, particularly in patients with low stage disease. The reported incidence of multifocal renal cell carcinoma is approximately 15%, and it depends on tumor size, histology and stage. The risk of multifocal disease is low (less than 5%), when the maximal diameter of the primary tumor is 4 cm or less. Minimally invasive modalities of tumor resection or destruction show promising results, however they should be reserved for selected patients and await improvement in technology. Only when long-term follow-up data is available these methods might become routine clinical practice. CONCLUSIONS: Nephron sparing surgery provides effective therapy for patients in whom preservation of renal function is a relevant clinical consideration. Accumulating data in appropriately selected patients suggest a long-term functional advantage gained by the maximal preservation of unaffected renal parenchyma without sacrificing cancer control.

Carcinoma, Renal Cell↗

PubMed2003

Herpes simplex virus type 2 seropositivity in a sexually transmitted disease clinic in Israel.

BACKGROUND: Seroepidemeliogic surveys have provided valuable information on the prevalence and incidence of herpes simplex virus-2 infection in general and in selected populations. OBJECTIVE: To review the reliability of traditional diagnostic approaches in herpes simplex virus-2 infection. METHODS: In this cross-sectional study, 472 patients attending a clinic for sexually transmitted disease in 1998-1999 were evaluated for HSV-2 infection through collection of epidemiologic and clinical data. HSV-2 infection was confirmed by the presence of specific viral glycoprotein, gG-2, antibody in sera. RESULTS: The seroprevalence of HSV-2 among clinic attendees was 9.33%. Of these attendees only 22% presented with or reported a history of typical vesicular lesions in the genital area. Infection rate was higher in patients with multiple sex partners (20.8% vs. 8.7%, P < or = 0.0023), in individuals aged 30 or older (12.6 vs. 6.4%, P = 0.03) and in the Israeli Jewish population as compared to the Israeli Arab population (11.1% vs. 2.4%, P < or = 0.01). Females with multiple sex partners exhibited higher rates of infection than did their male counterparts (50 vs. 16.1%, P < or = 0.0275). CONCLUSION: The findings support the need for HSV-2 serologic testing in patients presenting to STD clinics even when typical genital lesions are not evident but where risk factors for HSV-2 infection are identified.

Adult↗

PubMed2002

Metastatic breast cancer to the bladder: a diagnostic challenge and review of the literature.

Nineteen cases of breast cancer metastatic to the bladder and diagnosed in living patients have been identified in the English literature. Most patients were symptomatic with evidence of disseminated disease at the time of diagnosis. Metastasis usually occurred many years after diagnosis, and the prognosis was poor. The definitive modality for diagnosis in all cases was cystoscopy, which demonstrated an abnormal lesion in the bladder wall that was confirmed on biopsy. In our study, we discuss the case of a patient with breast cancer metastatic to the bladder despite a normal cystoscopic evaluation.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2002

Bladder tumor antigen stat test in non-urothelial malignant urologic conditions.

BACKGROUND: The bladder tumor antigen stat is a simple and fast one-step immunochromatographic assay for the detection of bladder tumor-associated antigen in urine. OBJECTIVES: To evaluate the BTA stat in non-bladder cancer patients in order to identify the categories contributing to its low specificity. METHODS: A single voided urine sample was collected from 45 patients treated in the urology clinic for conditions not related to bladder cancer. Each urine sample was examined by the BTA stat test and cytology. RESULTS: The overall specificity of the BTA stat test was 44%, which was significantly lower than that of urine cytology, 90%. The false positive rates for the BTA stat test varied among the different clinical categories, being highest in cases of urinary tract calculi (90%), and benign prostatic hypertrophy (73%). Exclusion of these categories from data analysis improved BTA stat specificity to 66%. CONCLUSIONS: Clinical categories contributing to low BTA stat specificity can be identified, and their exclusion improves the specificity of this test.

Antigens, Neoplasm↗