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D Chopin

Publications and source records attributed to D Chopin.

At least 55 records · Page 3Linked to original sources

[Urinary leukocytes as a new prognostic marker of therapeutic response and of adverse effects associated with the maintenance treatment with endovesical BCG, for the prophylaxis of superficial bladder tumors].

UNLABELLED: The use of Bacillus Calmette-Guérin (BCG) vaccine as immunotherapy for superficial bladder cancer constitutes a major progress, although it remains limited by the development of adverse effects and problems related to safety. No individual tool is currently available in clinical practice to predict the efficacy or adverse effects of BCG therapy. These problems are accentuated in the case of maintenance therapy according to the protocol of D.L. Lamm. OBJECTIVES: To define whether the urinary leukocyte count observed after intravesical BCG instillation could be associated with adverse effects and efficacy of treatment. MATERIAL AND METHODS: A cohort of 72 consecutive patients (518 instillations) was studied prospectively. We defined four classes of adverse effects associated with BCG, according to their type, severity and duration. In combination with this classification, we performed systematic optical urinary leukocyte count on the third day after each instillation (KOVA-Slide 10). RESULTS: A high urinary leukocyte count (cut-off value: 165,000/ml) was correlated with absence of recurrence (p = 0.009). The adverse effect classification also demonstrated that urinary leukocyte count was related to the severity and duration of adverse effects (p < 0.0001). Median values observed for class I, II and III adverse effects were 40,000 leukocytes/ml, 150,000 leukocytes/ml and 350,000 leukocytes/ml, respectively. No class IV adverse effects were observed. The risk of developing class III adverse effects was increased when the urinary leukocyte count was greater than 86,000 leukocytes per ml. CONCLUSION: These results suggest a probable relationship between efficacy and safety of BCG, during maintenance therapy. Randomized prospective studies are necessary to evaluate urinary leukocyte count as a tool for adaptation and optimization of BCG therapy.

Adjuvants, Immunologic↗

[Tendinopathy associated with fluoroquinolones: individuals at risk, incriminated physiopathologic mechanisms, therapeutic management].

The use of fluoroquinolones in urology has grown considerably over recent years. Unfortunately, although these molecules are not associated with severe life-threatening complications, they have nevertheless been associated with tendon lesions responsible for functional disability. The frequency of these complications is probably underestimated. There is a variable lag-time (3 to 5 days) between introduction of the antibacterial and onset of pain. The symptom most frequently reported is pain over the tendon affected and the tendons most frequently affected are those submitted to high constraints. Bilateral lesions are present in 66% of cases. Although Pefloxacin is associated with the highest frequency of tendon complications (2.7% versus 0.2-0.3% for other fluoroquinolones), the duration of treatment appears to be important in every case, with a peak frequency after a fortnight of treatment. Although these complications were considered for a long time to be associated with patients presenting certain risk factors (age, steroid therapy, renal failure), they can also occur suddenly, in young adult sportsmen or non-sportsmen, with no known tendon disease. Several hypotheses have been proposed to explain the development of these cases of tendinopathy: immuno-allergic mechanisms, direct toxicity of the molecule on collagen fibres, cell-mediated oxidative aggression, or tendon necrosis due to vascular mechanisms. The outcome remains favourable in 75% of cases of tendinitis and in 49% of cases for tendon rupture. Contraindications must therefore be identified and the duration of treatment must be adapted, as the functional handicap can be long and particularly severe.

Anti-Infective Agents↗

[Remote laparoscopic radical prostatectomy carried out with a robot. Report of a case].

Robotics has been commonly employed in numerous industrial fields for several decades. However, the application of this technology to surgery is a recent innovation. It provides new possibilities for facilitating specific surgical tasks, especially in the field of laparoscopy. We report a case of laparoscopic radical prostatectomy completed with the help of a remotely controlled da Vinci robot. This system offered a user friendly surgical platform and enhanced surgical dexterity. Operating time was 420 minutes and the hospital stay was 4 days. The bladder catheter was removed after 3 days. One week later, the patient was fully continent. Pathologic examination showed a pT3a tumor, with negative margins. Robotically assisted laparoscopic radical prostatectomy is feasible. Further developments in this field of technology may have new applications in laparoscopic telesurgery.

Equipment Design↗

[Nephrectomy in a living donor by retroperitoneal laparoscopy or lomboscopy].

INTRODUCTION: The advantages of laparoscopic live donor nephrectomy are now well documented. This new approach can lower donor morbidity and could stimulate living related organ donation. We described our original operative technique and report our preliminary results. MATERIAL AND METHODS: Since 1998, we have used the retroperitoneal laparoscopy in tree related living donors. Advantages and inconvenient of this new surgical procedure were discussed with each donors and inform consent obtained. The left kidney was harvested in the three cases. RESULTS: The operative time was inferior to 280 minutes, warm ischemia less than five minutes and bleeding less than 150 mL. Patients were discharged between the 2nd and 3rd post-operative days. CONCLUSION: Retroperitoneal laparoscopy is a valuable alternative in transplant centres with skilled laparoscopic surgeons.

Humans↗

[Postoperative complications following kidney transplantation].

Despite the remarkable development of kidney transplantation techniques, surgical complications are still a very important factor affecting the final outcome of kidney transplantation. After 92 kidney transplantations (22 from cadaver donors and 70 from living donors) performed at Skopje hospital (Macedonia), we observed the following complications: nine (10%) urinary fistula, five (5%) graft ruptures, seven (8%) lymphoceles, two (2%) urinary calculosis, two (2%) intestinal perforations, four (4%) renal artery stenoses, one (1%) renal artery thrombosis, and seven (8%) early complications following surgical incision. Complications were detected by either ultrasonography, intravenous pyelography, percutaneous nephrostomy with anterograde pyelography, computerized tomography, and intravenous digital angiography. They were subsequently treated by application of modern surgical procedures: use of the ureter (termino-terminal or uretero-pyelic anastomosis) for treatment of urinary fistulas; conservative surgery using tissue glue and external compression with polyglactin 910 (Vicryl) mesh for graft ruptures; drainage and application of sclerosants under ultrasound control and intraperitoneal marsupialization for the clinically relevant lymphoceles; transluminal angioplasty with balloon dilatation in case of significant arterial stenosis; extracorporeal shock wave lithotripsy and surgery for urinary calculi. Intestinal perforations and problems relating to parietal tissue were quickly solved using standard surgical techniques. On total, rejection of the graft occurred in four (4%) cases following surgical complications, while one death was encountered due to septic peritonitis. We consider the percentage of surgical complications acceptable, as this work consists of a pioneering effort in this Balkan region.

Adult↗

[Results of 25 years of kidney transplantation].

Between 1975 and 2000, 1008 renal transplantations were performed in 935 recipients at Henri Mondor hospital. The mean objective of this study is to analyse patient and graft survivals at long term. For kidney transplantations performed respectively before and after 1985, ten years patient survival was 74.3% +/- 0.03 and 85.7% +/- 0.01, p = 0.03 and ten years graft survival was 39.5% +/- 0.04 and 71.9% +/- 0.02 after 1985, p = 0.001. Since 1985, an enhancement in graft actuarial survival still improved (one year survival 86.1% +/- 0.01 versus 90.8% +/- 0.02, three years survival 78.5% +/- 0.02 versus 85.5% +/- 0.02, five years survival 71.7% +/- 0.02 versus 78.8% +/- 0.04, for the years 1985-1994 versus 1995-2000, p < or = 0.05). Immunosuppressive drugs may contribute to results enhancement in kidney transplantation while other non immunologic factors are becoming more predominant.

Adolescent↗

[Mechanisms of action of BCG: towards a new individualized therapeutic approach?].

A better knowledge of antitumour immunity and the mechanisms allowing the tumour to overcome the host's immune surveillance has led to progress in the understanding of the mechanisms of action of Bacille Calmette-Guérin (BCG), as the local intravesical immune response is intimately related to the interaction of three systems: the host (the patient), the BCG (mycobacteria) and the tumour. This interaction gives rise to a cascade of immunological events, some of which are essential to the protective action of BCG against relapse and tumour progression. The immune response to BCG is currently considered to comprise three phases. First of all, the BCG adheres to the urothelium and is then phagocytosed by antigen-presenting cells. This phase corresponds to early release of so-called inflammatory cytokines (IL1, IL6, IL8). These cytokines could be responsible for certain adverse effects, but could also participate in cytotoxic phenomena. The second phase consists of recognition of bacterial antigens by helper CD4 lymphocytes, which mainly release IL2 and IFNg (Th1 response). This cellular activation leads to the third phase: amplification of cytotoxic populations capable of killing tumour cells: CD8, gd lymphocytes, macrophages, NK, LAK, BAK cells. All these cells also produce cytokines, which participate in regulation of the immune response. The understanding of these mechanisms of action, urinary cytokine assays, a better definition of cytotoxic cells and their role, molecular analysis of the tumour and probably certain genetic characteristics of the host will allow the elaboration of more effective immunization protocols by defining an individualized therapeutic approach.

Adjuvants, Immunologic↗

Tumour suppressive properties of fibroblast growth factor receptor 2-IIIb in human bladder cancer.

FGFRs (fibroblast growth factor receptors) are encoded by four genes (FGFR1-4). Alternative splicing results in various receptor isoforms. The FGFR2-IIIb variant is present in a wide variety of epithelia, including the bladder epithelium. Recently, we have shown that FGFR2-IIIb is downregulated in a subset of transitional cell carcinomas of the bladder, and that this downregulation is associated with a poor prognosis. We investigated possible tumour suppressive properties of FGFR2-IIIb by transfecting two human bladder tumour cell lines, J82 and T24, which have no endogenous FGFR2-IIIb expression, with FGFR2-IIIb cDNA. No stable clones expressing FGFR2-IIIb were isolated with the J82 cell line. For the T24 cell line, stable transfectants expressing FGFR2-IIIb had reduced growth in vitro and formed fewer tumours in nude mice which, in addition, grew more slowly. The potential mechanisms leading to decreased FGFR2-IIIb mRNA levels were also investigated. The 5' region of the human FGFR2 gene was isolated and found to contain a CpG island which was partially methylated in more than half the cell lines and tumours which do not express FGFR2-IIIb. No homozygous deletion was identified in any of the tumours or cell lines with reduced levels of FGFR2-IIIb. Mutational analysis of the entire coding region of FGFR2-IIIb at the transcript level was performed in 33 bladder tumours. In addition to normal FGFR2-IIIb mRNA, abnormal transcripts were detected in two tumour samples. These abnormal mRNAs resulted from exon skipping which affected the region encoding the kinase domain. Altogether, these results show that FGFR2-IIIb has tumour growth suppressive properties in bladder carcinomas and suggest possible mechanisms of FGFR2 gene inactivation.

Animals↗

[Arterial hypertension due to compression of the renal artery, revealing ovarian cancer].

BACKGROUND: The etiologic work-up of hypertension with hyperaldosteronism and elevated serum renin includes search for renal artery stenosis. Intrinsic stenosis is a common finding, but hypertension secondary to extrinsic compression of the renal artery is exceptional. CASE REPORT: A 48-year-old woman with an uneventful history was hospitalized for recent onset hypertension. Laboratory tests showed hypokaliemia, and elevated aldosterone and renin. Duplex Doppler exploration of the renal vessels evidenced extrinsic compression of the left renal artery by a tumoral mass found to be a nodal metastasis at surgery. Pathology reported cancer of the ovary. Blood pressure, and aldosterone and renin levels returned to normal after complete tumor resection. No antihypertensive treatment was required. CONCLUSION: This is undoubtedly the first case of metastatic cancer of the ovary revealed by hypertension; it can be added to the list of 49 other published cases of extrinsic compression of the renal artery by various causes leading to hypertension. In most cases, surgical removal of the obstacle or nephrectomy provided cure of the hypertension.

Female↗

Involvement of heparin affin regulatory peptide in human prostate cancer.

BACKGROUND: Heparin affin regulatory peptide (HARP) composes, together with midkine (MK), a new family of heparin-binding growth/differentiation factors. Recently, HARP was incriminated in cancer progression, as an angiogenic factor and as a tumor growth factor. In this study, we analyzed the possible involvement of HARP in human prostate cancer (Pca). METHODS: The localization of HARP protein and its mRNAs in normal prostate (n = 5), benign prostate hyperplasia (BPH) (n = 7), and prostate cancer (Pca) (n = 9) was analyzed by immunohistochemistry and in situ hybridization. The mitogenic activity of this growth factor for prostate epithelial cells was determined with a thymidine incorporation assay. HARP cDNA was transfected into normal prostate epithelial (PNT-1A) cells, and their growth was evaluated by soft-agar growth assay. RESULTS: We found HARP protein associated with epithelial cells in PCa but not in normal prostate or BPH, while the corresponding mRNAs were located in the stromal compartment. Furthermore, HARP is mitogenic for PNT-1A, LNCaP, and DU-145 cells. Overexpression of the human HARP in PNT-1A transfected cells induced both anchorage-independent growth and growth at low serum concentrations. CONCLUSIONS: Our results suggest that HARP may act in a paracrine manner from mesenchymal to tumoral epithelial cells, and may play a role in the molecular mechanisms that regulate prostate tumor cell growth.

3T3 Cells↗

Perineal approach to radical prostatectomy in kidney transplant recipients with localized prostate cancer.

Close urologic follow-up of renal transplant candidates and recipients often reveals prostate carcinoma at an early stage. Two patients who underwent renal transplantation for end-stage disease also underwent radical perineal prostatectomy for localized prostate carcinoma, 3 years after grafting in 1 patient and 4 years before grafting in the other. The perineal approach to prostatectomy may facilitate later renal transplantation and avoid allograft damage.

Adenocarcinoma↗

Results of pyeloureterostomy after ureterovesical anastomosis complications in renal transplantation.

OBJECTIVES: The most frequent urologic complications after renal transplantation involve the ureterovesical anastomosis (ie, leakage, stenosis, and reflux), with a frequency of 1% to 30% in different series. We present the results of pyeloureterostomy using the recipient's ureter. METHODS: From 1988 to 1996, 570 cadaveric renal grafts were performed at our institution. A Lich Gregoir ureterovesical anastomosis was used in every case. Complications involving the anastomosis occurred in 19 cases (3.3%), with 10 stenoses (1.7%), 6 cases of leakage (1.1%), and 3 of reflux (0.5%). The mean donor age was 36.2 years, and the mean duration of cold ischemia was 29.4 hours. The mean recipient age was 41.3 years. Corrective surgery was performed 0.09 years (range 0.01 to 0.22) after transplantation for leakage, 1.13 years (range 0.14 to 5.11) for stenosis, and 5.55 years (range 0.51 to 9.71) for reflux. The recipient's ureter was stented with a ureteral catheter before median laparotomy, except in 3 cases of early leakage (less than 3 days). The recipient's ureter was cut, without the need for ipsilateral nephrectomy, and sutured to the graft pelvis. A nephroureterostomia stent (Gil Vernet stent) (12 cases) or a double J ureteral stent (7 cases) was used for urinary drainage. RESULTS: One graft was lost on day 1 through renal vein thrombosis. Percutaneous nephrostomy was performed on day 2 to clear an obstruction of the double J ureteral stent in one case, and a double J ureteral stent was inserted on day 2 because the nephrouretrostomia stent was incorrectly positioned in another case. Pyelographic controls on day 15 were normal in every case. The mean follow-up was 2.25 years (range 0.24 to 6.1) (2.9 years for leakage, 2.08 years for stenosis, and 1.44 years for reflux). One patient died with a functional graft 3 years after surgery. One graft was lost 4 years after surgery through chronic rejection. There were no complications affecting the ipsilateral kidney. No further ureteral complications occurred after surgery. The mean creatinine level 3 years after surgery was 1.59 mg/dL. CONCLUSIONS: Pyeloureterostomy is a safe and permanent treatment for complications of ureterovesical anastomosis and gives excellent results. The technique requires stenting of the recipient's ureter and graft drainage with a nephroureterostomia stent or a double J ureteral stent.

Adult↗

Differences in steroid 5alpha-reductase iso-enzymes expression between normal and pathological human prostate tissue.

We studied the expression level and cell-specific expression patterns of 5alpha-reductase (5alpha-R) types 1 and 2 iso-enzymes in human hyperplastic and malignant prostate tissue by semi-quantitative RT-PCR and in situ hybridisation analyses. In situ hybridisation established that 5alpha-R1 mRNA is preferentially expressed by epithelial cells and little expressed by stromal cells whereas 5alpha-R2 mRNA is expressed by both epithelium and stroma. Semi-quantitative RT-PCR has been performed on total RNA from different zones of normal prostate, BPH tissues and liver. We found that 5alpha-R1 and 5alpha-R2 mRNAs expression was near the same in all zones of normal prostate. In BPH tissue, 5alpha-R1 and 5alpha-R2 mRNAs expression was slightly but significantly increased, when it was compared to the levels recorded for normal prostate. In cancer samples, 5alpha-R1 mRNA expression was higher than in normal and hyperplastic prostate but the level of 5alpha-R2 mRNA was not statistically different from that observed in the different zones of normal prostate. In liver, 5alpha-R2 mRNA level was similar to that measured in BPH but 5alpha-R1 mRNA expression was ten times higher. The increase observed in 5alpha-R isoenzymes expression in BPH tissue could play an important role in the pathogenesis and/or maintenance of the disease.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Epithelial cell plasticity in development and tumor progression.

Various mechanisms of epithelial cell plasticity in morphogenesis have been studied at the genetic and molecular levels. Several control genes have been identified including genes encoding transcription factors and growth factor receptors. These mechanisms may be reactivated during the progression of carcinomas. One of the mechanisms underlying epithelial plasticity is the epithelial-mesenchymal transition. This process has been extensively studied using the NBT-II bladder carcinoma cell line. Cells of this line undergo a reversible transition following exposure to several growth factors including FGF-1, EGF, TGFalpha and SF/HGF, which activate tyrosine kinase surface receptors. Two separate transduction pathways have been identified. The transient activation of c-Src is involved in cytoskeleton remodeling whereas the Ras pathway controls the transcription of genes such as the transcription factor Slug which is involved in the internalization of desmosomes. These two pathways cooperate to induce the morphological transition, scattering and locomotion of fibroblast-like cells. Growth/scatter factor-producing NBT-II cells are more invasive than cells that do not contain this factor, in orthotopic confrontation assay. In vivo, these cells are very tumorigenic and may confer a more malignant phenotype on parental cells via a community effect. The role of several growth factors and their receptors has been investigated in human bladder carcinomas. A subset of these tumors with poor outcomes produce low levels of FGFR2-IIIb. The synthesis of this receptor de novo in bladder cell lines reduces proliferation in vitro and tumor growth in nude mice. FGFR2-IIIb functions as a tumor suppressor, consistent with the differentiation-inducing capacities of FGF receptors in the suprabasal cells of the skin. FGFR2-IIIb signaling may be involved in the maintenance of E-cadherin, the prototype epithelial adhesion molecule, which is only downregulated in a fraction of tumors with low FGFR2-IIIb synthesis. Human bladder tumors may also activate autocrine loops such as that for EGFR and their ligands, as already demonstrated for murine bladder tumors. Therefore, our results suggest that multifunctional growth factors and their receptors are involved in cell proliferation and epithelial cell plasticity, acting either as positive or negative regulators of tumor progression. The effect on the morphological transition is also clearly relevant to the mechanism governing dissemination and the formation of micrometastatic tumor cells. The extrapolation of these discoveries to human carcinomas should provide markers facilitating the more accurate prediction of the biological behavior of a given tumor and identify clinically and pathologically significant parameters. The identification of critical changes in the growth factor pathways involved in tumor progression will not only provide insight into the genetic and molecular basis of this process, but should also identify targets for new therapies.

Animals↗