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Featured researches published by Nir Kleinmann.


The Journal of Urology | 2009

Laparoscopic Partial Nephrectomy for Central Tumors: Analysis of Perioperative Outcomes and Complications

Andrei Nadu; Nir Kleinmann; Menachem Laufer; Zohar Dotan; Harry Winkler; Jacob Ramon

PURPOSE We report our experience with laparoscopic partial nephrectomy for central tumors compared to peripheral tumors to analyze the feasibility and safety of the laparoscopic approach to these complex cases. MATERIALS AND METHODS Between October 2002 and July 2007, 212 patients underwent laparoscopic partial nephrectomy. In 53 patients the tumor was central and in 159 it was peripheral. The preoperative, intraoperative and postoperative data, the type and incidence of complications, and the quality of excision in terms of surgical margin status were compared between the 2 groups. RESULTS Mean estimated blood loss (320 and 360 ml, respectively, p >0.05) and mean operative time (126 and 118 minutes, respectively, p >0.05) were similar in the central and peripheral tumor groups. Mean warm ischemia time in the central tumor group was longer (37 and 28 minutes, respectively, p <0.05) but median time was similar (30 and 29 minutes, respectively, p >0.05). The open conversion rate was significantly lower in the study group (1% vs 5.6%, p <0.05). The urological complication rate was similar in the 2 groups (9.4% vs 8.4%, p >0.05). However, different types of complications developed in each group. Four patients (7.5%) with central tumors had late hematuria (arterial pseudoaneurysm) and only 1 (1.9%) had a urine leak. Central tumors were larger (3.2 vs 2.5 cm) and more frequently malignant (94% vs 82%, p >0.05). Positive surgical margins were diagnosed in 0% vs 5% of cases (p <0.05). CONCLUSIONS Provided that there is adequate laparoscopic expertise the outcome of laparoscopic partial nephrectomy for central tumors is comparable to that of peripheral tumors. The main major complication in this group was late onset hematuria, which necessitated angiographic embolization. This facility should be available at centers where these advanced procedures are performed.


Urologic Oncology-seminars and Original Investigations | 2011

Does RNA editing play a role in the development of urinary bladder cancer

Dorit E. Zilberman; Michal Safran; Nurit Paz; Ninette Amariglio; Amos J. Simon; Edward Fridman; Nir Kleinmann; Jacob Ramon; Gideon Rechavi

PURPOSE A-to-I RNA editing is essential for the development of normal cells and is involved in a wide variety of biological pathways. Currently, limited information suggests linkage between changes in RNA editing levels and the development of cancer. We aimed to explore the possible linkage between altered RNA editing levels and the development of human urinary bladder neoplasms. MATERIALS AND METHODS Thirty-two patients underwent transurethral resection of bladder tumor. Normal and tumoral urinary bladder tissues were obtained from each patient during surgery. Total RNA was extracted from tissue cells and converted by RT-PCR reaction to cDNA molecules for further analysis. We explored known editing sites in RNA encoding for proteins (BLCAP, Cyfip2, FLNA, GluB Q/R) as well as in RNA transcribed from Alu elements in noncoding regions of the genes encoding for CARD11, FANCC, MDM4, BRCA1, and RBBP9 proteins. Editing levels were determined using Sequenom MassARRAY Compact Analyzer. RESULTS Eleven tumoral tissues obtained were low grade TCC, 14 high grade TCC, 1 CIS, and another 5 inflammation. One sample contained only normal tissue. We got a total number of 30 normal bladder tissue samples and overall 29 paired samples (i.e., normal and tumoral tissues obtained from the same patient). Statistical analysis revealed no significant changes in editing levels between normal and tumoral tissues. CONCLUSIONS Relying on the results obtained for 9 different editing sites, it can be determined that RNA editing is an epigenetic mechanism that does not participate in the evolution of urinary bladder cancer.


Arab journal of urology | 2012

Ureteroscopic treatment of larger renal calculi (>2 cm).

Demetrius H. Bagley; Kelly A. Healy; Nir Kleinmann

Abstract Objectives: To evaluate the current status of ureteroscopic lithotripsy (UL) for treating renal calculi of >2 cm, as advances in flexible ureteroscope design, accessory instrumentation and lithotrites have revolutionised the treatment of urinary calculi. While previously reserved for ureteric and small renal calculi, UL has gained an increasing role in the selective management of larger renal stone burdens. Methods: We searched the available databases, including PubMed, Google Scholar, and Scopus, for relevant reports in English, and the article bibliographies to identify additional relevant articles. Keywords included ureteroscopy, lithotripsy, renal calculi, and calculi >2 cm. Retrieved articles were reviewed to consider the number of patients, mean stone size, success rates, indications and complications. Results: In all, nine studies (417 patients) were eligible for inclusion. After one, two or three procedures the mean (range) success rates were 68.2 (23–84)%, 87.1 (79–91)% and 94.4 (90.1–96.7)%, respectively. Overall, the success rate was >90% with a mean of 1.2–2.3 procedures per patient. The overall complication rate was 10.3%, including six (1.4%) intraoperative and 37 (8.9%) postoperative complications, most of which were minor. The most common indications for UL were a failed previous treatment (46%), comorbidities (18.2%), and technical and anatomical factors (12.3%). Conclusions: UL is safe and effective for treating large renal calculi. While several procedures might be required for total stone clearance, UL should be considered a standard approach in the urologist’s options treating renal calculi of >2 cm.


Cuaj-canadian Urological Association Journal | 2015

The relative contribution of urine extravasation to elevate plasma creatinine levels in acute unilateral ureteral obstruction.

Barak Rosenzweig; Jehonathan H. Pinthus; Nir Kleinmann; Erel Joffe; Tomer Erlich; Eddie Fridman; Harry Winkler; Yoram Mor; Jacob Ramon; Zohar Dotan

INTRODUCTION Rising levels of plasma creatinine in the setting of acute unilateral ureteral obstruction (AUUO) often reflects acute renal failure, mandating kidney drainage. We hypothesize that re-absorption of peri-renal urine extravasation (PUE), a common result of UUO, contributes significantly to the elevation in plasma creatinine, rendering the latter an inaccurate benchmark for renal function. We explored this hypothesis in a rat model of AUUO and PUE. METHODS In total, 20 rats were equally divided into 4 groups. Groups 1 and 2 underwent unilateral ligation of the ureter with infiltration of rats urine (index group) or saline (control) into the peri-renal space. Two additional control groups underwent peri-renal injection of either urine or saline without AUUO. Plasma creatinine levels were determined immediately prior to the procedure (T0), and hourly for 3 hours (T1, T2 and T3). Renal histology was investigated after 3 hours. RESULTS Rats in the index group had a significantly greater increase in plasma creatinine levels over 3 hours compared to all other groups (p < 0.05). At T3, average plasma creatinine levels for the index group increased by 96% (0.49 ± 0.18 mg/dL) compared to 46% (0.23 ± 0.06 mg/dL increase) in the AUUO and saline group, and less than 15% rise in both the non-obstructed control groups. Our study limitations includes lack of spontaneous PUE and intraperitoneal surgical approach. CONCLUSIONS Absorption of peri-renal urine in the presence of AUUO is a significant contributor to rising plasma creatinine levels, beyond those attributable to the obstruction alone, and may overestimate the extent of the true renal functional impairment.


Breast Journal | 2005

A solitary metastasis of breast cancer to the urinary bladder.

Nir Kleinmann; Yoram Mor; Menachem Laufer; Mordechai Duvdevani; Edward Fridman; Jacob Ramon

Address correspondence and reprint requests to: Nir Kleinmann, MD, Department of Urology, Chaim Sheba Medical Center, Tel Hashomer, Ramat Gan, 52621, Israel, or e-mail: [email protected]. Figure 1. (a) Hematoxylin-eosin stain shows normal urothelium in the margins. In the center, a solid focus of the tumor is seen. (b) Hematoxylin-eosin stain shows atypical malignant cells with several mitoses, arranged in groups. (c) Positive staining for CA15-3. (d) Positive staining for CU-18.


American Journal of Roentgenology | 2016

Can Unenhanced CT Findings Predict Interventional Versus Conservative Treatment in Acute Renal Colic

Eyal Lotan; Omer Weissman; Larisa Guranda; Nir Kleinmann; Rachel Schor; Harry Winkler; Orith Portnoy

OBJECTIVE The purpose of this study was to determine the value of clinical parameters and radiologic findings on unenhanced CT to the choice between interventional and conservative management for patients with acute renal colic. MATERIALS AND METHODS Unenhanced CT records of 183 consecutive patients with acute renal colic were retrospectively reviewed. Urolithiasis was confirmed at both unenhanced CT and clinical follow-up findings of 80 patients (study group). Clinical parameters (signs of infection and renal indexes) and unenhanced CT findings (tissue rim sign, hydronephrosis, perinephric and periureteral edema, ureteral dilatation, renal attenuation, and stone characteristics) were graded and correlated with the choice of clinical management. ROC analysis was constructed for the most statistically significant parameters. RESULTS Forty-two patients (52%) were treated conservatively and 38 (48%) underwent interventional treatments. The relationship between shivering, fever, and leukocytosis and interventional treatment had low sensitivity (29%, 26%, and 16%, respectively) but very high specificity (98%, 95%, and 98%, respectively) (p < 0.05). Stone size and density were statistically significantly different between patients treated conservatively and those treated interventionally (size, 4.6 vs 6.7 mm; density, 730 vs 910 HU; p < 0.01). Stones larger than 6.5 mm with an attenuation value greater than 1100 HU and that were proximally located were more likely to be treated interventionally. CONCLUSION Larger stone size, higher density, proximal location, and complaints of shivering, fever, and leukocytosis are the most important parameters for predicting invasive management of acute renal colic. Other clinical and radiologic information may be useful as supportive findings but do not predict the choice of patient management.


Urology | 2018

Ureteroscopic Management of Large ≥ 2 cm Upper Tract Urothelial Carcinoma: A Comprehensive Twenty-three Year Experience

Kymora Scotland; Nir Kleinmann; Dillon Cason; Logan Hubbard; Ryuta Tanimoto; Kelly A. Healy; Scott G. Hubosky; Demetrius H. Bagley

OBJECTIVE To evaluate the effectiveness of ureteroscopy (URS) with laser ablation as an alternative treatment for upper tract urothelial carcinoma (UTUC) lesions larger than 2 cm. Traditionally, patients with large UTUC are treated with radical nephroureterectomy (RNU). However, in patients with pre-existing renal disease, a solitary kidney, or those who decline RNU, management of UTUC may prove challenging METHODS: An institutional database review identified 80 patients with biopsy proven low-grade UTUC who had at least one lesion larger than 2 cm. We collected clinical data including demographics, operative parameters, and pathologic features. Follow-up for all patients was standardized and included cystoscopy and URS every 3 months until clear, every 6 months through the fifth year, and yearly thereafter. We calculated rates of recurrence, progression, and overall survival. RESULTS In total, 86 unique lesions ≥2cm were identified in the 80 qualifying patients; mean tumor size was 3.04 cm. Median follow-up was 43.6 months. During follow-up of patients treated curatively, 90.5% of tumors had ipsilateral recurrence and 31.7% progressed in grade at a median of 26.3 months. RNU was performed in 16 patients (20%); mean time to surgery was 23.2 months. Overall survival was 75%, and cancer specific survival was 84% at 5-year follow-up. CONCLUSION Under strict surveillance, ureteroscopic management of large (≥ 2cm) UTUC lesions is a viable treatment alternative to RNU. While recurrence is common, URS can potentially preserve renal units in patients with large lesions.


International Urology and Nephrology | 2018

24-h urine metabolic profile: is it necessary in all kidney stone formers?

Yasmin Abu-Ghanem; Asaf Shvero; Nir Kleinmann; Harry Winkler; Dorit E. Zilberman

PurposeA 24-h urine metabolic profile (24-UMP) is an integral part of nephrolithiasis work-up. We aimed to explore whether it can be waived under certain circumstances.Materials and methodsWe reviewed our prospective registry database of patients seen at our outpatient clinic for nephrolithiasis between the years 2010 and 2017. Data included: gender, age at first stone, body mass index (BMI), self-reported comorbidities and family history of nephrolithiasis. A 24-UMP was obtained from each patient under random diet. The following were recorded: urine volume, urinary levels of sodium, calcium, uric acid, oxalate and citrate. Presence of at least one comorbidity (i.e., hypertension/diabetes/hyperlipidemia) was defined as “associated comorbidities” (AC). Their absence was defined as “no comorbidities” (NC). Subjects were divided into two subgroups: first-time and recurrent stone formers, which were further divided into two subgroups: 1st + AC; 1st + NC; recurrent + AC; recurrent + NC. 24-UMPs have been compared between the four groups.ResultsFour hundred and fifty-seven patients were included in the study. In the AC groups, patients demonstrated higher BMI levels (p = 0.001), and were statistically significantly obese (BMI > 30, p = 0.001) and older at first stone event (p = 0.001). First formers, either with AC or NC were more likely to have low urine volume (LUV) compared with recurrent formers (72.5 vs. 59.5%, p = 0.005). In the remaining metabolic abnormalities, no such differences were observed.ConclusionsFirst-time stone formers, either with or without AC are likely to demonstrate LUV as their primary metabolic abnormality in 24-UMP. Therefore, 24-UMP may be postponed until recurrent stone event.


The Journal of Urology | 2007

Laparoscopic Partial Nephrectomy: Single Center Experience With 140 Patients—Evolution of the Surgical Technique and its Impact on Patient Outcomes

Andrei Nadu; Yoram Mor; Menachem Laufer; Harry Winkler; Nir Kleinmann; Noam D. Kitrey; Jacob Ramon


Journal of Pediatric Urology | 2007

Testicular prosthesis insertion following testicular loss or atrophy during early childhood--technical aspects and evaluation of patient satisfaction.

Dorit E. Zilberman; Harry Winkler; Nir Kleinmann; Gil Raviv; Boris Chertin; J. Ramon; Yoram Mor

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Kelly A. Healy

Thomas Jefferson University

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Mark P. Schoenberg

Albert Einstein College of Medicine

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Scott G. Hubosky

Thomas Jefferson University Hospital

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