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Soroush Rais-Bahrami

Publications and source records attributed to Soroush Rais-Bahrami.

11 recordsLinked to original sources
PubMed2024

Molecular Characterization of Juxtaglomerular Cell Tumors: Evidence of Alterations in MAPK-RAS Pathway.

Juxtaglomerular cell tumor (JGCT) is a rare neoplasm, part of the family of mesenchymal tumors of the kidney. Although the pathophysiological and clinical correlates of JGCT are well known, as these tumors are an important cause of early-onset arterial hypertension refractory to medical treatment, their molecular background is unknown, with only few small studies investigating their karyotype. Herein we describe a multi-institutional cohort of JGCTs diagnosed by experienced genitourinary pathologists, evaluating clinical presentation and outcome, morphologic diversity, and, importantly, the molecular features. Ten JGCTs were collected from 9 institutions, studied by immunohistochemistry, and submitted to whole exome sequencing. Our findings highlight the morphologic heterogeneity of JGCT, which can mimic several kidney tumor entities. Three cases showed concerning histologic features, but the patient course was unremarkable, which suggests that morphologic evaluation alone cannot reliably predict the clinical behavior. Gain-of-function variants in RAS GTPases were detected in JGCTs, with no evidence of additional recurrent genomic alterations. In conclusion, we present the largest series of JGCT characterized by whole exome sequencing, highlighting the putative role of the MAPK-RAS pathway.

Humans↗
PubMed2007

Imaging the cavernous nerves in the rat prostate using optical coherence tomography.

INTRODUCTION: Improvements in identification, imaging, and visualization of the cavernous nerves (CNs) during radical prostatectomy, which are responsible for erectile function, may improve nerve preservation and post-operative potency. Optical coherence tomography (OCT) is capable of real-time, high-resolution, cross-sectional, in vivo tissue imaging. The rat prostate serves as an excellent model for studying the use of OCT for imaging the CNs, as the rat CN is a large, visible, and distinct bundle allowing for easy identification with OCT in addition to histologic confirmation. MATERIALS AND METHODS: Imaging was performed with the Niris OCT system and a handheld 8 Fr probe, capable of acquiring real-time images with 11-microm axial and 25-microm lateral resolution in tissue. Open surgical exposure of the prostate was performed on a total of six male rats, and OCT images of the prostate, CN, pelvic plexus ganglion, seminal vesicle, blood vessels, and periprostatic fat were acquired. CN electrical stimulation with simultaneous intracorporeal pressure measurements was performed to confirm proper identification of the CNs. The prostate and CNs were also processed for histologic analysis and further confirmation. RESULTS: Cross-sectional and longitudinal OCT images of the CNs were acquired and compared with histologic sections. The CN and ganglion could be differentiated from the surrounding prostate gland, seminal vesicle, blood vessels, bladder, and fatty tissue. CONCLUSIONS: We report preliminary results of OCT images of the rat CNs with histologic correlation and erectile stimulation measurements, thus providing interpretation of prostate structures as they appear in OCT images.

Animals↗
PubMed2006

Lmo7 is an emerin-binding protein that regulates the transcription of emerin and many other muscle-relevant genes.

X-linked Emery-Dreifuss muscular dystrophy (X-EDMD) is inherited through mutations in emerin, a nuclear membrane protein. Emerin has proposed roles in nuclear architecture and gene regulation, but direct molecular links to disease were unknown. We report that Lim-domain only 7 (Lmo7) binds emerin directly with 125 nM affinity; the C-terminal half of human Lmo7 (hLmo7C) was sufficient to bind emerin in vitro. Lmo7 appeared relevant to EDMD because a deletion that removes Lmo7 (plus eight exons of a neighboring gene) in mice causes dystrophic muscles [Semenova, E., Wang, X., Jablonski, M.M., Levorse, J. and Tilghman, S.M. (2003) An engineered 800 kilobase deletion of Uchl3 and Lmo7 on mouse chromosome 14 causes defects in viability, postnatal growth and degeneration of muscle and retina. Hum. Mol. Genet., 12, 1301-1312]. Lmo7 localizes in the nucleus, cytoplasm and cell surface, particularly adhesion junctions [Ooshio, T., Irie, K., Morimoto, K., Fukuhara, A., Imai, T. and Takai, Y. (2004) Involvement of LMO7 in the association of two cell-cell adhesion molecules, nectin and E-cadherin, through afadin and alpha-actinin in epithelial cells. J. Biol. Chem., 279, 31365-31373]. Our data suggest endogenous Lmo7 is a nucleocytoplasmic shuttling protein, and might also localize at focal adhesions in HeLa cells. Two key results show that Lmo7 regulates emerin gene expression: rat Lmo7 isoforms directly activated a luciferase reporter gene in vivo, and emerin mRNA expression decreased 93% in Lmo7-downregulated HeLa cells. Thus, Lmo7 not only binds emerin protein but is also required for emerin gene transcription. Microarray analysis of Lmo7-downregulated HeLa cells identified over 4200 misregulated genes, including 46 genes important for muscle or heart. Misregulation of 11 genes, including four (CREBBP, NAP1L1, LAP2, RBL2) known to be misregulated in X-EDMD patients and emerin-null mice [Bakay, M., Wang, Z., Melcon, G., Schiltz, L., Xuan, J., Zhao, P., Sartorelli, V., Seo, J., Pegoraro, E., Angelini, C. et al. (2006) Nuclear envelope dystrophies show a transcriptional fingerprint suggesting disruption of Rb-MyoD pathways in muscle regeneration. Brain, 129, 996-1013; Melcon, G., Kozlov, S., Cutler, D.A., Sullivan, T., Hernandez, L., Zhao, P., Mitchell, S., Nader, G., Bakay, M., Rottman, J.N. et al. (2006) Loss of emerin at the nuclear envelope disrupts the Rb1/E2F and MyoD pathways during muscle regeneration. Hum. Mol. Genet., 15, 637-651] was confirmed by real-time PCR. Overexpression of wild-type emerin, but not emerin mutant P183H (which causes EDMD and selectively disrupts binding to Lmo7), decreased the expression of CREBBP, NAP1L1 and LAP2, suggesting Lmo7 activity is both EDMD-relevant and inhibited by direct binding to emerin. We conclude that Lmo7 positively regulates many EDMD-relevant genes (including emerin), and is feedback-regulated by binding to emerin.

Cell Membrane↗
PubMed2006

Primary carcinoid tumors of the kidney.

PURPOSE: We describe in detail the features of carcinoid tumors of the kidney. We evaluated possible prognostic factors. MATERIALS AND METHODS: An extensive search was performed in the medical literature regarding primary carcinoid tumors of the kidney. Epidemiological, clinical, diagnostic, histopathological, therapeutic and prognostic data were evaluated. Several potential risk factors were compared with the incidence of metastases and clinical outcome of the patients. RESULTS: A total of 56 case reports were reviewed. Median patient age was 49 years. Horseshoe kidneys were present in 17.8% of cases. Incidental diagnosis was made in 28.6% of patients. The most common symptom was abdominal or flank pain and neuroendocrine syndromes occurred with only 12.7% of primary renal carcinoid tumors. Of the patients 73.6% presented with tumors larger than 4 cm. Metastases were present in 45.6% of patients at initial diagnosis and almost 60% with tumors greater than 4 cm had metastases. CONCLUSIONS: Renal carcinoid is the second most prevalent genitourinary carcinoid in each sex, following testicular carcinoids in men and ovarian tumors in women. Significant adverse prognostic factors include age greater than 40 years, tumor size greater than 4 cm, purely solid tumors on the cut surface, mitotic rate higher than 1/10 high power fields, metastasis at initial diagnosis and tumors extending throughout the renal capsule.

Calcinosis↗
PubMed2006

Reinstatement of continuous ambulatory peritoneal dialysis after transperitoneal laparoscopic nephrectomy.

OBJECTIVES: To assess the early reinstatement of continuous ambulatory peritoneal dialysis (CAPD) after transperitoneal radical nephrectomy. METHODS: The medical records of the 3 patients who were using CAPD before laparoscopic radical nephrectomy were retrospectively reviewed. All 3 were reinstated on CAPD during the second postoperative week. RESULTS: In these 3 patients, the mean hospital stay was 6 days (range 3 to 9), and CAPD was reinitiated 12.7 days (range 10 to 14) after laparoscopic surgery. During the interim between surgery and reinstituting CAPD, all 3 patients underwent hemodialysis (HD) in the hospital and were discharged to local outpatient HD centers. No difficulties were associated with the transition to CAPD, and no complications had occurred after the reinstatement of regular CAPD regimens at a mean follow-up of 11 months (range 10 to 13) in this group of patients. CONCLUSIONS: The results of this study have shown that CAPD can be reinstated within 2 weeks of laparoscopic transperitoneal radical nephrectomy without short-term complications.

Adult↗
PubMed2006

Intraoperative conversion of laparoscopic partial nephrectomy.

PURPOSE: To assess the incidence of conversion from laparoscopic partial nephrectomy (LPN) to open surgery or laparoscopic radical nephrectomy (LRN) when liberal selection criteria are utilized. PATIENTS AND METHODS: A retrospective review of medical records was done for all patients scheduled for LPN at our institution from January 2000 through March 2004. The preoperative risk factors, intraoperative course, and pathologic outcomes of patients who were converted to LRN were compared with those of the cohort of patients who underwent LPN as originally scheduled. RESULTS: Among the 257 operations that started as LPN, 35 (13.6%) were converted to LRN and 4 (1.6%) to open surgery. Age, tumor size, operating time, and hypertension were significantly higher in patients requiring conversion in than those who underwent completed LPN. Patients over the age of 70 had a 3.8-fold higher risk of requiring conversion, and, independent of age, patients with tumor>4.0 cm had a 4-fold increase in the likelihood of conversion to LRN. CONCLUSION: Of the preoperatively determined factors compared across the cohort of patients who underwent LPN and the cohort of patients converted to LRN, only tumor size and patient age were predictive of an increased risk of conversion. Other variables, including sex, side of affected kidney, clinical stage, ASA score, comorbidity with hypertension or diabetes mellitus, and surgeon were not significant in predicting conversion.

Adult↗
PubMed2006

Unusual renal pathology associated with a Wilms tumor in a 15-month-old infant.

Beckwith-Wiedemann syndrome is an overgrowth dis-order that predisposes to the development of a variety of malignancies including Wilms tumor. Pathologists may suspect the presence of Beckwith-Wiedemann syndrome, which may be clinically subtle, on the basis of the histopathology of the renal parenchyma adjacent to a Wilms tumor. These kidneys typically harbor multiple nephrogenic rests (especially perilobar nephrogenic rests), and their medullas have blunted papillae resulting from excessive fibromyxoid stroma, decreased collecting ducts, and decreased Henle loops. This complex of findings constitutes the so-called Beckwith Medulla. Extensions of this stroma-rich medulla into the cortex results in characteristic dysplastic medullary-ray nodules. Identification of these histologic abnormalities by the pathologist should prompt the clinician to evaluate the child for Beckwith-Wiedemann syndrome. Proper screening of these children can allow for early detection of cancers and treatment while these cancers are curable.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Laparoscopic retroperitoneal lymph node dissection after prior open retroperitoneal lymphadenectomy and chemotherapy.

Laparoscopic retroperitoneal lymphadenectomy for testicular cancer is a challenging surgical procedure. Several factors can increase the difficulty, including prior chemotherapy or open surgery. We present a case of a laparoscopic "redo" postchemotherapy nodal dissection to treat a residual retroperitoneal mass in a patient with non-seminomatous germ cell tumor. This approach allowed rapid recovery, and at 2.5 years after surgery no evidence of tumor recurrence was seen.

Adult↗
PubMed2005

Laparoscopic ureteral reimplantation: a simplified dome advancement technique.

Laparoscopic Boari flap reimplantation has been used to treat long distal ureteral strictures. This technique requires extensive bladder mobilization and complex intracorporeal suturing. This demonstrates a novel laparoscopic bladder dome advancement approach for ureteral reimplantation. This technique obviates the need for bladder pedicle dissection and simplifies the required suturing.

Humans↗
PubMed2005

Laparoscopic renal-adrenal surgery in patients on oral anticoagulant therapy.

PURPOSE: Patients requiring chronic anticoagulation are theoretically at increased risk for hemorrhage or thromboembolism perioperatively. Experience with laparoscopic renal/adrenal surgery in patients on chronic warfarin is limited. We assessed hemorrhagic/thromboembolic complications in this group of patients. MATERIALS AND METHODS: The records of 787 patients undergoing laparoscopic renal/adrenal surgery were retrospectively reviewed. A total of 25 patients on chronic oral anticoagulation with warfarin were identified. The indications for warfarin therapy as well as perioperative management were reviewed. Clinical parameters, including operative time, estimated blood loss, hemorrhagic/thromboembolic complications and transfusions, were documented and compared with those in patients not receiving chronic anticoagulation. RESULTS: Atrial fibrillation (56% of cases) and a prosthetic mitral valve (28%) were the most frequent indications for chronic anticoagulation. Bridging anticoagulation with unfractionated heparin was the most frequent management method (68% of cases). Patients with anticoagulation were older (p <0.001) and hospitalized longer (<0.001) than those without anticoagulation. Operative time, estimated blood loss and the conversion rate were not significantly different between the groups. However patients on chronic warfarin significantly more often required transfusion (24% vs 5.2%, p <0.005) and had more postoperative bleeding episodes (8% vs 0.9%, p <0.05) than patients not on chronic anticoagulation. No thromboembolic events occurred in the anticoagulated group, while 3 occurred in the nonanticoagulated group (p = 1). CONCLUSIONS: Laparoscopic renal/adrenal surgery in patients requiring chronic anticoagulation therapy can be performed safely. The risk of intraoperative bleeding is not increased, although the incidence of postoperative bleeding as well as transfusions is higher.

Administration, Oral↗