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Featured researches published by Roman Jednak.


Clinical & Experimental Metastasis | 1994

The loss of E-cadherin mRNA transcripts in rat prostatic tumors is accompanied by increased expression of mRNA transcripts encoding fibronectin and its receptor

Colin D. MacCalman; Pnina Brodt; Jean D. Doublet; Roman Jednak; Mostafa M. Elhilali; Michel Bazinet; Orest W. Blaschuk

We compared the levels of mRNA transcripts encoding E-cadherin, N-cadherin,Β1 integrin subunit,α5 integrin subunit and fibronectin in the normal rat prostate gland, as well as in tumors derived from three invasive sublines (G, MatLyLu, AT-2) of the Dunning R-3227 rat prostatic adenocarcinoma. E-cadherin mRNA transcripts were only detectable in total RNA extracts prepared from normal rat prostates, whereas N-cadherin mRNA transcripts were only found in normal rat brains. In contrast, the mRNA transcripts encoding theΒ1 integrin subunit,α5 integrin subunit and fibronectin were all elevated in the tumors, as compared to the levels of these transcripts in normal tissues. Our results suggest that there is an inverse correlation between cadherin and integrin mRNA levels in rat prostatic tumors.


International Urology and Nephrology | 2007

Gartner duct cyst simplified treatment approach

Saleh Binsaleh; Mana Al-Assiri; Roman Jednak; Mohammed El-Sherbiny

We present two patients with Gartner’s duct cyst managed with simple marsupialization and successful long-term follow up.


Journal of Pediatric Urology | 2016

Testicular hypertrophy as a predictor for contralateral monorchism: Retrospective review of prospectively recorded data

A. Hodhod; John-Paul Capolicchio; Roman Jednak; Mohamed El-Sherbiny

OBJECTIVES Testicular hypertrophy has previously been evaluated as a predictor of monorchism. However, its implication in clinical practice is not well evaluated. The aim of the present study was to examine its value in planning the operative time. PATIENTS AND METHODS Medical charts of prospectively recorded data of 76 consecutive patients with unilateral impalpable testis from 2011 to 2014 were reviewed at the present institute. Inclusion criteria included prepubertal patients with non-palpable testes by examination under anesthesia. Contralateral testes were prospectively measured using a Takihara orchidometer. Orchiectomy or orchiopexy was performed according to the viability of the undescended testis (UDT). Collected data included age of surgery, contralateral testicular size, surgical time and laparoscopic findings. A ROC curve was used to define the best cut-off volume of the contralateral testis that can predict ipsilateral testicular viability. The Students t-test was used to examine if this cut-off volume would be useful in allocating the operative time. RESULTS Of 76 patients, four palpable testes by examination under anesthesia were excluded. The remaining 72 patients were included in the study. Ipsilateral normal viable testes were found in 26 (36.1%) patients, while 46 (63.9%) had non-viable testes (testicular nubbins or vanishing testes) (Figure). A contralateral testicular volume > 2 ml was significantly predictive for monorchism with 71.7% sensitivity and 100% specificity (P < 0.001). The mean operative time for management of UDT with a contralateral size >2 ml was 50 min, which was significantly shorter than that for UDT with a contralateral size ≤ 2 ml, which was 88 min (P < 0.001). DISCUSSION In previously published reports, the cut-off value for testicular hypertrophy that predicts monorchism greatly varied. This is likely due to the different methods used for testicular measurements that make it impractical to make a direct comparison. The usefulness of predicting monorchism before surgery has not previously been used as a guide for allocating operative time in the management of a unilateral non-palpable testicle. This study had some limitations, including a relatively small sample size and involvement of different surgeons, which may have affected the operative time. CONCLUSION Using the cut-off volume of a contralateral testis >2 ml as a predictor for monorchism can reduce the allocated operative time by approximately one third.


Urology Annals | 2013

Outcome of surgical management of non-palpable testes

Gacia Geuvbashian; Roman Jednak; John-Paul Capolicchio; Mohamed El-Sherbiny

Background: We reviewed the success rates of orchidopexies performed for non-palpable testes at our institution and correlated preoperative and intraoperative findings to eventual outcomes. Materials and Methods: We retrospectively reviewed ninty five medical records of patients who underwent laparoscopic exploration for the assessment of a non-palpable testes between 1996 and 2009. Intra-operative data for one hundrad eight non-palpable testes were collected. Operative success was defined as a testis comparable in size or slightly smaller than the contra-lateral testis with normal consistency on the last follow-up. Results: There were seventy (65%) viable testes at exploration, thirty one nubbins (29%) removed and 7 (6%) absent. In the seventy six unilateral cases, contra-lateral hypertrophy was found in twinty five (33%) testes. Of which, twinty one (84%) were associated with absent testes or finding of a nubbin rather than a viable testis. In contrast, absent testes or finding of a nubbin was noted in 12 of 51 (23.5%) patients without contra-lateral hypertrophy. The difference was statistically significant (P < 0.001). Mean follow-up was seventeen months. Of the fifty testes in which the testicular artery was preserved, 7 were lost to follow-up and 3 of the remaining fourty three (7%) were atrophic. The twinty testes that underwent Fowler-Stephens orchidopexy (FSO) had a similar rate of atrophy, with only 1 (5%) atrophic testis identified following staged FSO (P > 0.83). Interpretation: Testicular atrophy rate was similar in both artery sparing and Fowler-Stephens orchidopexies. Contra-lateral hypertrophy was significantly associated with absent testes or finding of a nubbin rather than a viable testis.


Archive | 2014

Issues Related to Pediatric Urology

Arpana Iyengar; John-Paul Capolicchio; Mohamed El-Sherbiny; Roman Jednak; Konrad M. Szymanski

Children with urological malformations should be treated and followed by a “team” of a pediatric nephrologist, a pediatric urologist, and a pediatrician. In many developing countries, pediatric surgeons handle urological concerns since there may not be dedicated pediatric urologists available. Many children with nephro-urological abnormalities need long-term follow-up. This chapter discusses in some of the more common conditions, such as antenatally diagnosed hydronephrosis, posterior urethral valves, urinary tract infections, vesicoureteric reflux, neurogenic bladder and voiding dysfunction, and stone disease.


American Journal of Physiology-renal Physiology | 2007

PAX2 is reactivated in urinary tract obstruction and partially protects collecting duct cells from programmed cell death

Tiffany Cohen; Oleg Loutochin; Moamen Amin; John-Paul Capolicchio; Paul Goodyer; Roman Jednak


Environmental Health Perspectives | 2017

A Case–Control Study of Maternal Polybrominated Diphenyl Ether (PBDE) Exposure and Cryptorchidism in Canadian Populations

Cynthia G. Goodyer; Shirley Poon; Katarina Aleksa; Laura Hou; Amanda Carnevale; Roman Jednak; Sherif Emil; Darius J. Bägli; Sumit Dave; Barbara F. Hales; Jonathan Chevrier


Journal of Pediatric Urology | 2009

HOW DO TOILET-TRAINED KIDS VOID FOLLOWING TUBULARIZED INCISED PLATE REPAIR OF HYPOSPADIAS?

Waleed Eassa; Fayez Almodhen; Alex Brzezinski; Jean-Paul Capolichio; Roman Jednak; Mohamed El Sherbiny


Journal of Pediatric Urology | 2017

Transurethral incision of ureterocele: Does the time of presentation affect the need for further surgical interventions?

A. Hodhod; Roman Jednak; J. Khriguian; Mohamed El-Sherbiny


Journal of Pediatric Urology | 2010

The Anterior Approach to Right Retroperitoneoscopic Adrenalectomy (RPA) in Children. A Point of Technique and Initial Experience

Waleed Eassa; Mohamed El Sherbiny; Roman Jednak; John Paul Capolicchio

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Joao L. Pippi Salle

Montreal Children's Hospital

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Alex Brzezinski

Montreal Children's Hospital

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