Publications by authors named "Majid Eshghi"

21 Publications

  • Page 1 of 1

Endovascular Stapler Complications During Minimally Invasive Nephrectomy: An Updated Review of the FDA MAUDE database from 2009-2019.

Urology 2021 Feb 15. Epub 2021 Feb 15.

New York Medical College/Westchester Medical Center, Valhalla NY, 40 Sunshine Cottage Road, 19 Skyline Building 1S-B48, Valhalla NY 10595, Phone: (914) 594-2440, Fax: (914) 594 -2431. Electronic address:

Objective: To characterize the rates of endovascular stapler complications during hilar ligation in minimally invasive radical nephrectomy over the last 10 years.

Material And Methods: We reviewed the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database from January 1, 2009 to August 1, 2019. Staplers were categorized according to type, namely Ethicon Inc. endocutters (Johnson & Johnson, New Brunswick NJ); Endo-GIA™ (Medtronic, Minneapolis MN); and Endo-TA™ (Medtronic, Minneapolis MN).

Results: There were 383 cases of complications involving staplers, 63% with Ethicon endocutters; 28% with GIA; and 9% with TA. 22 deaths (5.7% of total complications) were attributed to staplers. No deaths or reoperations occurred due to TA staplers. TA staplers were also associated with a reduced incidence of conversion to open as compared to Ethicon and GIA staplers. Apart from one device, manufacturer evaluation of returned devices either showed no abnormalities or attributed fault to improper use of staplers.

Discussion: We characterized stapler complications during a ten-year period for minimally invasive radical nephrectomy. No deaths or reoperations occurred due to TA staplers, perhaps due to cutting and stapling occurring in separate steps. Based on manufacturer evaluation attributing stapling malfunctions to human errors, training of operating room staff on proper use of these devices is critical to prevent potentially significant complications from occurring.
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http://dx.doi.org/10.1016/j.urology.2021.02.010DOI Listing
February 2021

Contemporary Trends in Percutaneous Nephrolithomy Across New York State: A Review of the Statewide Planning and Research Cooperative System.

J Endourol 2019 09 23;33(9):699-703. Epub 2019 Jul 23.

Department of Urology, New York Medical College, Valhalla, New York.

Percutaneous nephrolithotomy (PCNL) is a complex multistep surgery that has shown a steady increase in use for the past decade in the United States. We sought to evaluate the trends and factors associated with PCNL usage across New York State (NYS). Our goal was to characterize patient demographics and socioeconomic factors across high-, medium-, and low-volume institutions. We searched the NYS, Statewide Planning and Research Cooperative System (SPARCS) database from 2006 to 2014 using ICD-9 Procedure Codes 55.04 (percutaneous nephrostomy with fragmentation) for all hospital discharges. Patient demographics including age, gender, race, insurance status, and length of hospital stay were obtained. We characterized each hospital as a low-, medium-, or high-volume center by year. Patient and hospital demographics were compared and reported using chi-square analysis and Student's -test for categorical and continuous variables, respectively, with statistical significance as a -value of <0.05. We identified a total of 4576 procedures performed from 2006 to 2014 at a total of 77 hospitals in NYS (Table 1). Total PCNL volume performed across all NYS hospitals increased in the past decade, with the greatest number of procedures performed in 2012 to 2013. Low-volume institutions were more likely to provide care to minority populations (21.4% 17.3%,  < 0.001) and those with Medicaid (25.5% 21.5%,  < 0.001). High-volume institutions provided care to patients with private insurance (42.1% 34.0%,  < 0.001) and had a shorter length of stay (3.3 days 4.1 days,  < 0.001). Our data provide insight into the patient demographics of those treated at high-, medium-, and low-volume hospitals for PCNL across NYS. Significant differences in race, insurance status, and length of stay were noted between low- and high-volume institutions, indicating that racial and socioeconomic factors play a role in access to care at high-volume centers.
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http://dx.doi.org/10.1089/end.2019.0115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6918525PMC
September 2019

The Two-Point Technique for Fluoroscopic-Guided Endoscopic Procedures in Urology: A Validation Study.

J Endourol 2019 09 28;33(9):691-695. Epub 2019 Jun 28.

Department of Urology, New York Medical College, Valhalla, New York.

The widespread use of diagnostic and therapeutic ionizing radiation raises concerns regarding excessive occupational and patient exposure. In this study, we test a novel fluoroscopic technique that has the potential to minimize radiation dose during urologic procedures. A prospective evaluation of all patients undergoing endoscopic urologic procedures in our institution was conducted. A "two-point technique (TPT)" is described in which the fluoroscope image intensifier (c-arm) is shifted between caudal and cephalad set points of the operative field. We wished to determine whether patient radiation exposure was lower with TPT than with a non-structured conventional technique, referred to as the cognitive fluoroscopic technique (CFT), in which the manipulation of the c-arm was at the discretion of the user. We obtained all clinical, radiographic, and fluoroscopic data of patients in the study period and used unpaired nonparametric statistical analysis of univariates entered stepwise into a logistic regression model. A total of 106 endoscopic urologic procedures from January 2016 to November 2018 were reviewed. Forty-four (41.5%) cases were performed using TPT and 62 (58.5%) using CFT. The mean fluoroscopy time of TPT CFT was 71.1 (±60.8) seconds 104.5 (±91.6) seconds, respectively ( = 0.04), and the mean radiation dose on TPT CFT was 11.6 (±10.6) mGy 20.3 (±24.3) mGy, respectively ( = 0.03). TPT was an independent predictor of reduced operative room (OR) time and fluoro time ( < 0.05), while body mass index, age, and operator were not. The "TPT" helps reducing radiation dose and fluoroscopic time during endoscopic urologic procedures. The TPT is useful to lower radiation exposure to patients and OR staff.
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http://dx.doi.org/10.1089/end.2019.0077DOI Listing
September 2019

Device Malfunctions and Complications Associated with Benign Prostatic Hyperplasia Surgery: Review of the Manufacturer and User Facility Device Experience Database.

J Endourol 2019 06 24;33(6):448-454. Epub 2019 May 24.

1 Department of Urology, New York Medical College, Valhalla, New York.

Multiple surgical therapies for benign prostatic hyperplasia (BPH) have been developed to decrease complications and increase provider efficiency. We investigated contemporary BPH treatment device-related adverse events by searching a publicly available database. The Manufacturer and User Facility Device Experience (MAUDE) database was queried for contemporary BPH treatments. All devices were evaluated for malfunction, patient complications, and manufacturer review. The MAUDE adverse event classification system was used to standardize complications. Univariate analysis was performed to identify associations between BPH devices and adverse events. A total of 2567 reports were identified: transurethral resection of the prostate (TURP) 197 (7.67%), holmium laser enucleation of the prostate (HoLEP) 39 (1.52%), GreenLight™ 2315 (90.2%), and UroLift 16 (0.62%). The most common deviations for each modality included cutting loop detachment during TURP 116 (58.9%), morcellator dysfunction for HoLEP 23 (58.9%), tip fracture/detachment for GreenLight (68.8%), and failure to deploy during UroLift 10 (62.5%). Only 18 (0.7%) patients required medical/surgical management (MAUDE II-IV) due to a device complication. No significant relationship was seen between each modality and complications; however, morcellator use (27.8%) was observed in higher grade complications. Manufacturer review occurred in 61.7% of cases, with 41.3% of reviewed cases finding the operator the cause of the malfunction. Each BPH modality investigated had minimal patient harm with over 99% of patients experiencing no complication after device malfunction. Of note, great care should be taken with morcellator use during HoLEP as it had the greatest number of MAUDE II to IV complications among all devices. Manufacturer review revealed that over 40% of cases were due to misuse by the user. Therefore, urologists should select the modalities they are most familiar with to decrease patient harm and prevent device malfunctions.
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http://dx.doi.org/10.1089/end.2019.0067DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7207054PMC
June 2019

Metastatic Colorectal Adenocarcinoma in a Bifid Ureter.

J Endourol Case Rep 2019 18;5(1):13-15. Epub 2019 Mar 18.

Department of Urology, New York Medical College, Valhalla, New York.

Secondary malignancies of the ureter are uncommon. We report the diagnosis and management of metastatic colon cancer to the bifurcation of a bifid ureter. A 59-year-old man presented with diffuse metastasis with right hydronephrosis in both renal moieties of a partially duplicated system and an enhancing lesion within the proximal common ureter. Ureteral biopsy was positive for colorectal adenocarcinoma. The patient was subsequently started on palliative chemoradiation. The ureter is a rare location for hematogenous/lymphatic metastases. When a ureteral mass is present on imaging, ureteroscopy should be performed to characterize the extent of tumor and to rule out secondary malignancy.
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http://dx.doi.org/10.1089/cren.2018.0100DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6461055PMC
March 2019

Prophylactic effect of ethyl pyruvate on renal ischemia/reperfusion injury mediated through oxidative stress.

Int Urol Nephrol 2019 Jan 31;51(1):85-92. Epub 2018 Oct 31.

Department of Urology, New York Medical College, Valhalla, NY, 10595, USA.

Purpose: As oxidative stress (OXS) has been shown to play a primary role in renal ischemia/reperfusion injury (RIRI), we investigated whether antioxidant such as ethyl pyruvate (EPy) might effectively prevent RIRI. Possible prophylactic effects of EPy and mannitol (Mann), one of perioperative agents often used, were tested against harmful OXS in vitro.

Methods: Hydrogen peroxide (HO) was used to exert OXS on the renal proximal tubular MDCK cells. Severity of OXS and protective effects of EPy and Mann were assessed by lipid peroxidation assay and cell viability test, respectively. The cytotoxic mechanism of HO was explored by examining the status of glycolysis, metabolic signaling pathways, cell cycle, and induction of apoptosis.

Results: Although HO (500 µM) increased OXS by ~ 3.5 times of controls, EPy (1 mM) fully reduced it to the basal level. Cell viability declined to merely 10% by HO was regained to > 90% with EPy. Hexokinase activity and ATP level also declined significantly by HO, but they sustained 80-90% with EPy. Additionally, HO led to the modulations of metabolic signaling regulators, a G cell cycle arrest, and induction of apoptosis, which were yet prevented with EPy. Unlike EPy, Mann had virtually little effects.

Conclusions: OXS can indeed lead to the significant cell viability reduction through its adverse cellular effects, ultimately resulting in RIRI. However, EPy appears to prevent these effects and protect MDCK cells, while Mann does not. Thus, EPy could be a more effective prophylactic renoprotective agent (than Mann) against oxidative renal cell injury including RIRI.
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http://dx.doi.org/10.1007/s11255-018-2020-9DOI Listing
January 2019

Prostate Cancer Screening Trends After United States Preventative Services Task Force Guidelines in an Underserved Population.

Health Equity 2018 1;2(1):55-61. Epub 2018 May 1.

Department of Urology, New York Medical College, Valhalla, New York.

Prostate cancer screening is a controversial topic. We examined trends in Prostate Specific Antigen (PSA) testing in an underserved population before and after the United States Preventative Services Task Force (USPSTF) recommendation against screening. Data were collected on all PSA and cholesterol screening tests from 2008 to 2014. We examined the trend of these tests and prostate biopsies while comparing this data to lipid panel data to adjust for changes in patient population. A decrease in PSA screening was observed from 2010 through 2014, with the greatest decline in 2012. The age group most affected was patients aged 55-69 years. The amount of prostate biopsies during this period decreased as well. Decreased rates of PSA screening were observed in our urban hospital population that preceded the publication of the USPSTF guidelines. The incidence of prostate biopsies decreased in this timeframe. It now remains to be demonstrated whether decreased PSA screening rates impact the diagnosis of and ultimately the survival from prostate cancer.
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http://dx.doi.org/10.1089/heq.2018.0004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5963250PMC
May 2018

Percutaneous and Endoscopic Management of Nephrolithiasis in a Patient with Five Native Ureters (Trifid Right and Bifid Left Collecting System).

J Endourol Case Rep 2018 1;4(1):32-34. Epub 2018 Mar 1.

Department of Urology, New York Medical College, Valhalla, New York.

Triplication of the ureter is a rare urologic finding that has been well described in the literature. Patients can present with urinary tract infections, incontinence, and calculi. We present the case of a patient with extensive stone burden with right trifid and left bifid collecting systems. Stone management was performed with a multimodal approach using a combination of endoscopic and percutaneous approaches. Our systematic and staged approach highlights a method for efficacious stone treatment in a complex endourologic case.
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http://dx.doi.org/10.1089/cren.2017.0146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5865629PMC
March 2018

Device-Related Adverse Events During Percutaneous Nephrolithotomy: Review of the Manufacturer and User Facility Device Experience Database.

J Endourol 2017 10;31(10):1007-1011

1 Department of Urology, New York Medical College , Valhalla, New York.

Introduction And Objectives: Percutaneous nephrolithotomy (PCNL) is an established technique for removal of large stones from the upper urinary tract. It is a complex multistep procedure requiring several classes of instruments that are subject to operator misuse and device malfunction. We report device-related adverse events during PCNL from the Manufacturer and User Facility Device Experience (MAUDE) database using a recently developed standardized classification system.

Materials And Methods: The MAUDE database was queried for "percutaneous nephrolithotomy" from 2006 to 2016. The circumstances and patient complications associated with classes of devices used during PCNL were identified. We then utilized a novel MAUDE classification system to categorize clinical events. Logistic regression analysis was performed to identify associations between device classes and severe adverse events.

Results: A total of 218 device-related events were reported. The most common classes included: lithotripter 53 (24.3%), wires 43 (19.7%), balloon dilators 30 (13.8%), and occlusion balloons 28 (12.8%). Reported patient complications included need for a second procedure 12 (28.6%), bleeding 8 (19.0%), retained fragments 7 (16.7%), prolonged procedure 4 (9.5%), ureteral injury 2 (4.8%), and conversion to an open procedure 3 (7.1%). Using a MAUDE classification system, 176 complications (81%) were Level I (mild/none), 26 (12%) were Level II (moderate), 15 (7%) were Level III (severe), and 1 (0.5%) was Level IV (life threatening). On univariate analysis, balloon dilators had the highest risk of Level II-IV complications compared with the other device classes [odds ratio: 4.33, confidence interval: 1.978, 9.493, p < 0.001]. The device was evaluated by the manufacturer in 93 (42.7%) cases, with 54.8% of reviewed cases listing the source of malfunction as misuse by the operator.

Conclusions: PCNL is subject to a wide range of device-related adverse events. A MAUDE classification system is useful for standardized, clinically-relevant reporting of events. Our findings highlight the importance of proper surgeon training with devices to maximize efficiency and decrease harm.
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http://dx.doi.org/10.1089/end.2017.0343DOI Listing
October 2017

Antioxidant and Renoprotective Effects of Mushroom Extract: Implication in Prevention of Nephrolithiasis.

J Clin Med Res 2016 Dec 26;8(12):908-915. Epub 2016 Oct 26.

Department of Urology, New York Medical College, Valhalla, NY, USA.

Background: The pathogenesis of nephrolithiasis (kidney stone) remains elusive, while several therapeutic options are available but not effective as we expected. Accumulating data yet suggest that oxidative stress (generation of oxygen free radicals) may play a primary role in its occurrence. Particularly, calcium oxalate (CaOx) is a key element in the most common form (> 75%) of kidney stones, and its crystal form known as CaOx monohydrate (COM) has been shown to exert oxidative stress, facilitating CaOx stone formation. Hence, diminishing oxidative stress with certain antioxidants could be a potential strategic approach. We are interested in a bioactive extract of Poria mushroom, PE, which has been shown to have antioxidant and renoprotective activities. Accordingly, we investigated if PE might have antioxidant activity that would have implication in prevention of kidney stone formation.

Methods: Renal epithelial LLC-PK cells were employed and exposed to COM or hydrogen peroxide (HO) as a positive control capable of exerting oxidative stress. Possible antioxidant and protective effects of PE against oxidative stress (exerted by COM or HO) were assessed by cell viability test and lipid peroxidation (LPO) assay. To explore its protective mechanism, two glycolytic parameters, hexokinase (HK) activity and ATP synthesis, were examined and cell cycle analysis was also performed.

Results: Both HO and COM led to a significant (P < 0.05) reduction in cell viability, accompanied by severe oxidative stress assessed by LPO assay. Such oxidative stress also caused the significant decline in HK activity and cellular ATP level, indicating the inhibition of glycolysis. Cell cycle analysis further indicated that oxidative stress interfered with cell cycle, inducing a G cell cycle arrest that presumably results in the cessation of cell proliferation. However, PE was capable of significantly preventing or diminishing all these cellular effects mediated through oxidative stress (exerted by HO and COM).

Conclusions: The present study shows that the mushroom extract PE appears to have antioxidant and renoprotective effects against oxidative stress exerted by COM in renal cells. Therefore, PE with antioxidant activity is considered a promising natural agent that may have clinical implications in prevention of nephrolithiasis primarily induced by oxidative stress.
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http://dx.doi.org/10.14740/jocmr2781wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5087632PMC
December 2016

Alternative therapeutic approach to renal-cell carcinoma: induction of apoptosis with combination of vitamin K3 and D-fraction.

J Endourol 2013 Dec;27(12):1499-503

Department of Urology, New York Medical College , Valhalla, New York.

Purpose: Because of a dismal prognosis for advanced renal-cell carcinoma (RCC), an alternative therapeutic approach, using vitamin K3 (VK3) and D-fraction (DF) was investigated. VK3 is a synthetic VK derivative and DF is a bioactive mushroom extract, and they have been shown to have antitumor activity. We examined if the combination of VK3 and DF would exhibit the improved anticancer effect on RCC in vitro.

Materials And Methods: Human RCC, ACHN cell line, were treated with varying concentrations of VK3, DF, or a combination of the two. Cell viability was assessed at 72 hours by MTT assay. To explore the possible anticancer mechanism, studies on cell cycle, chromatin modifications, and apoptosis were conducted.

Results: VK3 alone led to a ~20% reduction in cell viability at 4 μM, while DF alone induced a 20% to 45% viability reduction at ≥ 500 μg/mL. A combination of VK3 (4 μM) and DF (300 μg/mL) led to a drastic >90% viability reduction, however. Cell cycle analysis indicated that VK3/DF treatment induced a G1 cell cycle arrest, accompanied by the up-regulation of p21(WAF1) and p27(Kip1). Histone deacetylase (HDAC) was also significantly (~60%) inactivated, indicating chromatin modifications. In addition, Western blot analysis revealed that the up-regulation of Bax and activation of poly-(ADP-ribose)-polymerase (PARP) were seen in VK3/DF-treated cells, indicating induction of apoptosis.

Conclusions: The combination of VK3 and DF can lead to a profound reduction in ACHN cell viability, through a p21(WAF1)-mediated G1 cell cycle arrest, and ultimately induces apoptosis. Therefore, the combination of VK3/DF may have clinical implications as an alternative, improved therapeutic modality for advanced RCC.
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http://dx.doi.org/10.1089/end.2013.0207DOI Listing
December 2013

Preventive effect of specific antioxidant on oxidative renal cell injury associated with renal crystal formation.

Urology 2013 Aug 21;82(2):489.e1-7. Epub 2013 Jun 21.

Department of Urology, New York Medical College, Valhalla, NY, USA.

Objective: To investigate whether calcium oxalate monohydrate (COM), a key element of hyperoxaluria, would induce renal cell injury through oxidative stress and also whether certain antioxidants could prevent chemically induced renal crystal formation in rats.

Materials And Methods: COM-exerted oxidative stress on the kidney epithelial Madin-Darby canine kidney cells was assessed using the lipid peroxidation assay. Glyoxalase I (Gly-I) activity was also determined. Two antioxidants, vitamin C and N-acetylcysteine (NAC), were then tested to determine whether they could abolish such oxidative stress in Madin-Darby canine kidney cells. Both antioxidants were also tested to determine whether they might prevent or reduce renal crystal formation induced with ethylene glycol (EG) and vitamin D3 (VD3) in Wistar rats.

Results: COM (200 μg/mL) demonstrated ∼1.3-fold greater oxidative stress with a significant reduction in cell viability and Gly-I activity compared with controls. However, such adverse events were almost completely prevented with NAC but not with vitamin C. In the animal study, no renal crystals were seen in the sham group. However, numerous crystals, with reduced Gly-I activity and elevated oxidative stress, were found in the EG-VD3 group. However, markedly (>70%) fewer crystals, with full Gly-I activity and diminished oxidative stress, were detected in the EG-VD3+NAC group.

Conclusion: COM exerted oxidative stress on Madin-Darby canine kidney cells, leading to cell viability reduction and Gly-I inactivation, with NAC fully preventing such adverse consequences. Similarly, numerous crystals with Gly-I inactivation and elevated oxidative stress seen in the rats (EG-VD3) were also significantly prevented with NAC supplement. Thus, NAC might have clinical implications in preventing oxidative renal cell injury and, ultimately, kidney stone formation.
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http://dx.doi.org/10.1016/j.urology.2013.03.065DOI Listing
August 2013

Induction of cell death in renal cell carcinoma with combination of D-fraction and vitamin C.

Integr Cancer Ther 2013 Sep 22;12(5):442-8. Epub 2013 Jan 22.

New York Medical College, Valhalla, NY 10595, USA.

Hypothesis: Although several conventional therapeutic options for advanced renal cell carcinoma (RCC) are currently available, the unsatisfactory outcomes demand establishing more effective interventions. D-fraction (PDF), a bioactive proteoglucan of Maitake mushroom, demonstrates anticancer and immunomodulatory activities, which are also shown to be potentiated by vitamin C (VC). We thus hypothesized that a combination of PDF and VC (PDF + VC) could be an alternative approach to more effectively inhibit the growth of RCC.

Study Design: We examined the dose-dependent effects of PDF + VC on RCC cell viability and also performed biochemical assays to explore the growth regulatory mechanism.

Methods: Human RCC, ACHN cell line, was employed and exposed to varying concentrations of PDF or VC and their combinations. Cell viability at specified times was determined by MTT assay. Lipid peroxidation assay, cell cycle analysis, and Western blot analysis were also performed.

Results: PDF or VC alone led to the significant reduction in cell viability at 72 hours with PDF >500 µg/mL and VC ≥300 µM. When various combinations of PDF and VC were tested, the combination of the ineffective concentrations of PDF (300 µg/mL) and VC (200 µM) resulted in ~90% cell death in 24 hours. Lipid peroxidation assay then indicated significantly (~2.5 fold) elevated oxidative stress with this PDF + VC. Cell cycle analysis also indicated a G1 cell cycle arrest following a 6-hour PDF + VC treatment. Western blots further revealed a downregulation of Bcl2, an upregulation of Bax, and proteolytic activation of PARP (poly[ADP-ribose] polymerase) in PDF + VC-treated cells, indicating induction of apoptosis.

Conclusion: The present study demonstrates that the combination of PDF and VC can become highly cytotoxic, inducing severe cell death in ACHN cells. This cytotoxic mechanism appears to be primarily attributed to oxidative stress, accompanied by a G1 cell cycle arrest. Such cell death induced by PDF + VC could be more likely linked to apoptosis, as indicated by the modulation of apoptosis regulators (Bcl2, Bax, and PARP). Therefore, as PDF and VC may work synergistically to induce apoptotic cell death, they may have clinical implications in an alternative, improved therapeutic modality for advanced RCC.
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http://dx.doi.org/10.1177/1534735412473643DOI Listing
September 2013

Nephrotoxin-induced renal cell injury involving biochemical alterations and its prevention with antioxidant.

J Clin Med Res 2012 Apr 23;4(2):95-101. Epub 2012 Mar 23.

Department of Urology, New York Medical College, Valhalla, New York, USA.

Background: Although nephrotoxic agents or nephrotoxins are known to induce acute renal cell injury, their cytotoxic action is not fully elucidated. It is thus crucial to explore such a cytotoxic mechanism and the increasing volume of reports indicated a significant involvement of oxidative stress. To test this possibility, we investigated if a nephrotoxin would exert oxidative stress, leading to renal cell injury accompanied by certain biochemical alterations. We also examined if specific antioxidant might help prevent such oxidative cell injury. These studies may then help establish a prophylactic or preventive modality for renal cell injury induced by nephrotoxins.

Methods: As glycerol has been commonly used for studying acute renal failure in animals, whether it would induce cellular injury was tested in renal proximal tubular OK cells in vitro. Cells were exposed to the varying concentrations of glycerol and cell number/viability was determined in 24 hours. Severity of oxidative stress was assessed by lipid peroxidation assay. Possible effects of glycerol on biochemical parameters were also examined on glyoxalase I activity and heat shock protein 90 using spectrophotometric (enzymatic) assay and Western blot analysis.

Results: Glycerol (2.5%) was highly cytotoxic to OK cells, inducing 95% cell death in 24 hours. Lipid peroxidation assay indicated that nearly 3-fold greater oxidative stress was exerted by this glycerol. Concurrently, glyoxalase I activity was drastically lost by 75% and heat shock protein 90 was partially degraded following glycerol exposure. However, N-acetylcysteine, a potent glutathione-based antioxidant, was capable of almost completely preventing the glycerol-mediated adverse outcomes, such as cell death, glyoxalase I inactivation, and heat shock protein 90 degradation.

Conclusions: Glycerol is cytotoxic, capable of inducing specific biochemical alterations such as inactivation of glyoxalase I and degradation of heat shock protein 90, which may reflect a breakdown of the cellular detoxification and defense systems, leading ultimately to OK cell death. Nevertheless, as N-acetylcysteine can provide full cytoprotection against such glycerol toxicity, it could be considered a prophylactic modality for nephrotoxin-induced oxidative renal cell injury and death.

Keywords: Glycerol; Glyoxalase I; Heat shock protein; N-acetylcysteine; Renal cell injury.
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http://dx.doi.org/10.4021/jocmr833wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3320129PMC
April 2012

Oxidative renal cell injury induced by calcium oxalate crystal and renoprotection with antioxidants: a possible role of oxidative stress in nephrolithiasis.

J Endourol 2010 Mar;24(3):339-45

Department of Urology, New York Medical College, Valhalla, New York 10595, USA.

Purpose: Calcium oxalate (CaOx) is one of the key elements for kidney stone formation, but the exact mechanism needs to be defined. CaOx has been shown to cause renal cell injury through oxidative stress, leading to potential crystal deposition in the kidneys. We thus investigated if CaOx crystal would induce such renal cell injury in vitro and also explored how it would be carried out.

Materials And Methods: Renal tubular epithelial LLC-PK(1) cells were employed, and CaOx monohydrate (COM) was used as CaOx crystal in this study. Cytotoxic effects of COM were assessed on cell viability and biochemical parameters, while protective effect of antioxidants against COM was also examined.

Results: COM demonstrated its cytotoxicity on LLC-PK(1) cells, exhibiting a approximately 35% cell viability reduction with 500 microg/mL COM in 6 hours. This was presumably attributed to oxidative stress, indicated by lipid peroxidation assay, and N-acetylcysteine (NAC), a potent antioxidant, indeed neutralized such COM cytotoxicity. Although COM also induced inactivation of glutathione-dependent enzymes and partial degradation of heat shock protein 90, these adverse effects were completely prevented with NAC. Moreover, such reduced cell viability with COM was rather associated with apoptosis, evidenced by DNA analysis.

Conclusion: COM is cytotoxic to LLC-PK(1) cells through oxidative stress, leading to the cell viability reduction, adverse effects on biochemical parameters, and, consequently, apoptosis. However, NAC effectively averted such severe cytotoxic effects, sustaining the renal cell integrity. Thus, NAC may provide full renoprotection against COM assault, preventing renal cell injury and ultimate stone formation.
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http://dx.doi.org/10.1089/end.2009.0205DOI Listing
March 2010

Endoscopic removal of a retained pelvic drain fragment with CO2 pneumoperitoneum.

J Endourol 2009 Jan;23(1):1-3

Department of Urology, New York Medical College, Valhalla, New York 10523, USA.

Retained drains are an infrequent and usually avoidable postsurgical complication. There are few reports in the contemporary literature regarding minimally invasive techniques to remove retained postsurgical drains. We present a novel technique for the removal of a retained deep pelvic Jackson-Pratt drain by means of a fluoroscopically guided transurethral endoscopic technique with minimal CO(2) pneumoperitoneum performed safely through a newly transected urethral stump under local anesthesia. The use of CO(2) pneumoperitoneum in place of saline irrigation is less likely to be associated with any untoward postoperative complications. This novel and effective technique will serve as a useful adjunct to the minimally invasive management of retained pelvic drains in postoperative patients who have undergone cystectomy and/or hysterectomy.
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http://dx.doi.org/10.1089/end.2008.0343DOI Listing
January 2009

Benefits of liver transplantation surgical techniques in the management of extensive retroperitoneal tumors.

World J Surg 2008 Nov;32(11):2403-7

Liver Transplant and Hepatobiliary Service, Westchester Medical Center, New York Medical College, Valhalla, NY, USA.

Background: The potential for massive hemorrhage imposes additional challenge in the management of retroperitoneal tumors. This report details technical considerations for the management of upper retroperitoneal tumors using principles of liver transplantation.

Methods: A retrospective chart review of patients who underwent surgery for extensive retroperitoneal tumors using techniques for liver transplantation from December 2002 to November 2007 was done.

Results: Twenty-four patients (14 males and 10 females with a mean age 57 years) underwent major retroperitoneal surgery. Renal cell carcinoma was the most common tumor seen in 17 patients. Mean tumor dimension was 12.4 cm. Abdominal exposure was achieved via bilateral subcostal incision with upper midline extension. Right hepatic lobe mobilization and isolation from the inferior vena cava (IVC) was performed in 23 cases. Fourteen patients had IVC involvement by tumor thrombus, which was infrahepatic in six, retrohepatic in five, and intra-atrial in three patients. Tumor thrombus was removed by cavotomy in seven cases, resection and plasty in four cases, IVC graft reconstruction in two cases, and one patient required IVC and atrial graft reconstruction. Liver resection was needed in seven patients to achieve R0 resection. The Pringle maneuver was used in three patients; total liver vascular isolation with venovenous bypass was required in two cases, transdiaphragmatic intrapericardial IVC control in one case, and cardiopulmonary bypass in one patient. There was no intraoperative or postoperative mortality and mean length of stay was 13 days.

Conclusion: Liver transplantation surgical principles help achieve exposure and vascular control of major vascular structures that enable safe resection of these extensive retroperitoneal tumors.
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http://dx.doi.org/10.1007/s00268-008-9714-6DOI Listing
November 2008

Cold-knife retrograde endopyelotomy: a long-term follow-up.

J Endourol 2008 Apr;22(4):657-60

New York Medical College, Westchester Medical Center, Department of Urology, Valhalla, New York, USA.

Cold-knife retrograde endopyelotomy is a simple, safe, and effective therapeutic option for primary and secondary symptomatic ureteropelvic junction obstruction (UPJO). Our long-term success rate with negligible complications demonstrates its durability and safety. Retrograde endopyelotomy should be considered a viable first-line treatment option for the management of patients with UPJOs.
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http://dx.doi.org/10.1089/end.2007.9828DOI Listing
April 2008

Accuracy of three-dimensional CT angiography for preoperative vascular evaluation of laparoscopic living renal donors.

J Endourol 2005 Apr;19(3):339-41

Department of Urology and Surgery, New York Medical College, Grasslands Road, Valhalla, New York, USA.

Purpose: A retrospective review of preoperative three-dimensional (3D) CT and the operative findings during laparoscopic donor nephrectomy.

Patients And Methods: Fifty-four consecutive patients underwent laparoscopic donor nephrectomy. Of these patients, 51 had preoperative 3D reconstructed CT scans. Each radiologic report was compared with the operative report.

Results: The 3D CT correctly identified the arteries in 98% of the patients and the veins in 96%.

Conclusions: Preoperative CT angiography can accurately identify the renal vasculature.
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http://dx.doi.org/10.1089/end.2005.19.339DOI Listing
April 2005

Holmium laser enucleation of the prostate in critically ill patients with technique modification.

J Endourol 2004 Oct;18(8):795-8

Department of Urology, New York Medical College, Valhalla, New York 10595, USA.

Background And Purpose: The use of the holmium:YAG laser for treating benign prostatic hyperplasia has developed substantially over the last decade. We present our experience with holmium laser enucleation of the prostate (HoLEP) in critically ill patients.

Patients And Methods: From January 1999 to May 2003, 40 critically ill patients with a mean age of 64.7 years (range 48-87 years) underwent HoLEP. Critically ill was defined as major comorbidity, including coronary and peripheral vascular disease, renal transplantation/immunosuppression, postradiation bleeding and sloughing, end-stage renal disease, advanced diabetes, severe anemia (hemoglobin <9.0 g/L), anticoagulant dependency, or bleeding diathesis. Preoperative and postoperative changes in hemoglobin (Hb) and sodium (Na), transfusion rates, and urethral catheter time were evaluated. This is a one-time instrument-insertion technique with the use of a large fiber and modification of the median lobe resection.

Results: There were no significant changes in Hb (8.7 g/L to 8.5 g/L) or Na (135 mmol/L to 137 mmol/L). One patient was returned to the operating room for bleeding, and this and one other patient required postoperative blood transfusions. The urethral catheter was removed within 36 hours in 34 patients, and all patients were catheter free within 4 weeks of surgery.

Conclusion: In our experience, HoLEP can be performed safely and effectively in patients who are critically ill.
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http://dx.doi.org/10.1089/end.2004.18.795DOI Listing
October 2004

Salvage extracorporeal shockwave lithotripsy after failed distal ureteroscopy.

J Endourol 2002 Aug;16(6):355-8

Department of Urology, New York Medical College, Valhalla, USA.

Background And Purpose: When intervention is necessary, controversy remains as to the best treatment modality for stones of the distal ureter. In general, ureteroscopy is favored over extracorporeal shockwave lithotripsy (SWL) as the treatment of choice for distal ureteral stones. Although uncommon, ureteroscopy failures have traditionally necessitated repeat ureteroscopy to retrieve retained stone fragments. We evaluated the efficacy of salvage SWL for failed primary distal ureteroscopy in the community setting.

Patients And Methods: From December 1989 to December 2000, 6099 patients underwent SWL with the Dornier HM4 lithotripter at our institution. We retrospectively identified 31 patients who had undergone the SWL after a failed distal ureteroscopy.

Results: The average stone size in these patients was 9.4 mm, the average time interval from ureteroscopy to SWL was 17.2 days, and the average number of shockwaves delivered was 2386. All patients had had stents placed after ureteroscopy. Twenty-seven patients (87%) had resolution of their stone burden after one SWL session. The remaining four patients underwent additional procedures.

Conclusions: Ureteroscopy is an effective modality for the treatment of distal ureteral stones. However, when unsuccessful, a salvage procedure may be necessary. Extracorporeal lithotripsy is a less invasive procedure with comparable success rates in the distal ureter. This report suggests that salvage SWL is an appropriate option for patients in whom distal ureteroscopic stone extraction fails.
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http://dx.doi.org/10.1089/089277902760261374DOI Listing
August 2002