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A Le Duc

Publications and source records attributed to A Le Duc.

At least 91 records · Page 5Linked to original sources
PubMed1994

[Laparoscopic surgery in urology: current status and trends in 1993].

Laparoscopic surgery in Urology is in a testing and development phase. The technique is currently used by some urologists to evaluate nonpalpable testes and to perform varicocelectomy or pelvic lymphadenectomy. Other standard open surgical procedures are experimentally being performed with the laparoscope. Owing to technologic advances laparoscopic surgery might become a part of routine urological care. We review the current impact of laparoscopy on Urology, we emphasize the advantages but also the risks of this new approach, and we discuss the benefit of these surgical procedures..

Adrenal Glands↗
PubMed1994

[Laparoscopic treatment of vesico-ureteral reflux in the pig. Preliminary report].

Laparoscopic urological surgery is currently in a phase of development. In order to evaluate the possibility of treating vesicoureteric reflux by laparoscopy, we performed an elongation of the submucosal ureteric tract via an extravesical approach (Lich-Gregoir) in 4 pigs. After creating a pneumoperitoneum, 4 trocars were introduced into the abdominal cavity. The peritoneum was incised at the level of the iliac vessels and the ureter was released at its middle portion as far as the ureterovesical junction. After coagulation, the detrusor was then incised proximally in relation to the ureterovesical junction, revealing 3 to 4 cm of vesical mucosa. The ureter was buried in the muscular groove, the edges of which were brought together by means of 6 metal staples. In 3 pigs, the bladder and ureter were immediately removed by laparotomy. On macroscopic examination, the staples correctly approximated the muscle layer without transfixing the bladder mucosa or ureter. The patency of the ureter was assessed with a probe. The submucosal tract was sufficiently large, preventing any ureteric compression. In 1 pig, the ureteric meati were incised endoscopically to create reflux. After laparoscopic elongation of the submucosal tract on one side, only the untreated ureter continued to reflux. Correction of vesicoureteric reflux is technically feasible in the pig. Longer studies are necessary before considering the application of this technique to man.

Animals↗
PubMed1994

[The role of Lithoclast in the endo-urologic treatment of urinary calculi (kidney and ureteral)].

The authors report their experience of the use of the Lithoclast in endocorporeal lithotripsy in 19 patients. This modality allowed the fragmentation of 24 renal stones and 14 ureteric stones with complete success in 58% of cases and partial success in 42% of cases. No failures of stone fragmentation were observed in this series with the Lithoclast. The authors consider this apparatus to be an effective and inexpensive method of endocorporeal lithotripsy for all types of urinary stones.

Adolescent↗
PubMed1993

Analysis of p53 antibodies in patients with various cancers define B-cell epitopes of human p53: distribution on primary structure and exposure on protein surface.

p53 antibodies have been found in sera of patients with breast and lung carcinomas and in children with B-lymphomas. We report here the presence of p53 antibodies in sera of patients with 11 different types of cancer. The frequency of seropositives for p53 varied among the different types of cancer, but a correlation with the frequency of p53 gene alteration was established. Using a powerful peptide enzyme-linked immunosorbent assay, we demonstrated that the immune response of patients with p53 antibodies was restricted to a small subset of peptides localized in the amino and carboxy termini of p53, whatever the type of cancer. Given the similarities of the patterns of immune responses in patients with p53 antibodies and animals hyperimmunized with human p53, we propose that the p53 humoral response is the result of a self-immunization process which is itself the consequence of p53 protein accumulation in tumor cells.

Amino Acid Sequence↗
PubMed1993

Anatomic basis of laparoscopic surgery in the male pelvis.

Laparoscopic surgery of the male pelvis remains a risky procedure, with around 15% of perioperative complications, as compared to 0.03% in laparoscopic surgery for gynecologic and obstetric conditions. Many of these complications are due to the surgeon's being faced with an unfamiliar anatomic situation in his approach through the laparoscopic operative field. We have added to the data of the literature our anatomic and clinical experience in order to define the anatomic basis of surgical risk in this type of procedure. While dissection lateral to the iliac vessels (surgery of the spermatic cord) is safe, dissection medial to these vessels is more risky because of the confined anatomic relationships and their variations (particularly vascular anomalies and variable relations of the ureter).

Humans↗
PubMed1993

Variations in arterial blood supply and the risk of hemorrhage during percutaneous treatment of lesions of the pelviureteral junction obstruction: report of a case of testicular artery arising from an inferior polar renal artery.

Acute hemorrhage during percutaneous surgery on the pelviureteric junction obstruction has been estimated to be 2-3%. Following the experience of peroperative bleeding from a vascular variation, the authors discuss the arterial anomalies of the renal pedicle which may carry the risk of hemorrhage during percutaneous surgery in this region. Arteries in front of or behind the renal pelvis are the cause of ureteropelvic function obstruction in 15-52% of cases and because of their close relationship with the upper urinary tract can complicate the procedure of endopyelotomy. Endourological techniques are inadequate for avoiding the risk of vascular damage during the necessary maneuvers. Inferior polar arteries occur in 9% of the population and their different courses are described. They are not always responsible for the vascular obstruction in the pelviureteric syndrome, and it is the exact determination of this responsibility that makes imaging essential. Arteriography performed in our case allowed embolisation of the damaged inferior polar artery and also showed the anomalous origin of the testicular artery from this polar artery; this appears to be only the second description of this anomaly. This variation is discussed in a review of the literature. In fact the testicular artery has a high or aberrant origin in 20% of cases; in 5-6% of these the origin is from a main or supernumerary renal artery. Origin from an inferior polar artery is exceptional.

Adult↗
PubMed1993

Percutaneous extra-anatomic nephrovesical diversion: preliminary report.

We propose a new approach to total ureteric replacement based on the use of a new spiraled composite tube. This tube is inserted percutaneously into the renal pelvis, then tracked subcutaneously and introduced into the bladder via a short incision. The tube is maintained in place by anchoring its spirals along the subcutaneous tract, and only the two silicone extremities are in continuous contact with the urine. We have used this technique for total replacement of the ureter in one renal transplant patient with a follow-up of 8 months and no complication. A longer follow-up is obviously necessary, but this new, minimally invasive approach, using a newly designed tube, would appear to give a new lease of life to an old, abandoned principle.

Adult↗
PubMed1993

[The value of MRI in ruptures of the corpus cavernosum].

MRI has only recently been described in the evaluation of traumatic rupture of the corpora cavernosa. Our case report emphasises the perfect correlation between the MRI findings and the anatomical lesion. This examination therefore constitutes a valuable aid in the pretreatment assessment of rupture of the corpora cavernosa.

Gadolinium↗
PubMed1993

[The treatment of metastasized kidney cancer. Current data and perspectives].

Metastatic renal cancer has a poor prognosis because of the limited impact of traditional treatment modalities on this tumour. The few long-term survivals obtained after isolated surgical resection of the primary tumour or its metastases can be attributed to the occasionally unpredictable natural history of this tumour and isolated surgical resection generally does not appear to improve the survival of these patients. Among non-surgical treatments, radiotherapy is purely palliative and hormone therapy has been shown to be ineffective. New therapeutic approaches have been recently developed, suggesting a possible improvement in the prognosis of metastatic renal cancer. A better understanding of the mechanisms of chemoresistance of renal cancer should lead, in the near future, to the use of drugs capable of increasing the efficacy of cytotoxic chemotherapy in this tumour. The results obtained with new forms of immunotherapy open up prospects for combined immunosurgical modalities.

Humans↗
PubMed1992

Anatomical bases of percutaneous surgery for calculi in horseshoe kidney.

Horseshoe kidney is a renal fusion which combines three anatomic abnormalities: ectopia, malrotation and vascular changes. These anomalies can be recognised separately to varying degrees in unfused kidneys. Necessary modifications of the standard technique for percutaneous nephrolithotomy (PNL) are directly deducible from analysis of the anatomic data of the imaging of horseshoe kidneys. We report our experience with 5 patients (7 kidneys) who underwent PNL for calculi in horseshoe kidneys. The percutaneous approach was performed under ultrasound and fluoroscopic monitoring. In situ disintegration by ultrasonic lithotripsy and nephrostomy drainage were necessary in all cases. Modifications of the standard PNL procedure are related to the anatomic changes. The lower abdominal position of a horseshoe kidney necessitates upper or middle calyceal puncture, while the malrotation necessitates a more posterior puncture. Monitoring of the puncture needle by fluoroscopy as it is advanced postero-anteriorly is more difficult and the risk of the surgeon's hand entering the radiation path is increased. The renal pelvis is deep and a long endoscope may be required. Aberrant segmental vessels may create potential hazards. The majority of problems in location can be avoided by use of an ultrasonically guided needle. Percutaneous nephrolithotomy is the treatment of choice for calculi in horseshoe kidneys for the following reasons: the high incidence of recurrent lithiasis in horseshoe kidney and the complexity of repeated surgical approaches diminish the acceptable results of open surgery; difficulties in focussing on the calculi and drainage problems militate against the success of extracorporeal shock wave lithotripsy (ESWL); PNL has a good success rate and the least morbidity.

Humans↗
PubMed1992

[Prostatic growth factors and benign hypertrophy of the prostate. Current knowledge and perspectives].

The importance of growth factors in prostatic regulation has been demonstrated for several years. These "prostatic" growth factors are ubiquitous polypeptides which are not specific to the prostate. To date, three principal families of growth factors appear to be potentially involved in the development of benign prostatic hypertrophy: Epidermal Growth Factor (EGF), Fibroblast Growth Factor (FGF), Transforming Growth Factor beta (TGF beta). The FGF and TGF beta families probably play a central role in the pathogenesis of benign prostatic hypertrophy. A better definition of the respective roles of growth factors and androgens in the control of prostatic growth opens up prospects for the future in the field of basic treatment of benign prostatic hypertrophy.

Growth Substances↗
PubMed1991

Immortalization of human adult normal prostatic epithelial cells by liposomes containing large T-SV40 gene.

Simian virus SV40 has been widely used to immortalize epithelial cells of mammalian origin. We report here, for the first time to our knowledge, the immortalization of normal adult prostatic epithelial cells in culture by transfection of a plasmid containing SV40 genome with a defective replication origin (SV40 ori-) encapsulated into liposomes. These cells (PNT1) have now been cultured for more than 12 months, and shown to contain the SV40 genome. They express large T protein, present the phenotype of differentiated luminal prostatic cells (positive with antibodies to cytokeratin 18, 19, weakly positive for prostatic acid phosphatase and prostatic specific antigen, negative with anticytokeratin 14 and KL2 antibody). PNT1 cells contain high affinity receptors for dihydrotestosterone. These cells provide a useful tool to study the biology and the pathology of adult prostatic epithelial cells, specially to understand the steps leading to prostatic transformation.

Acid Phosphatase↗
PubMed1990

[Screening for cancer of the prostate using prostate-specific antigen].

Systematic screening for prostate cancer was carried out in 600 men over 50 years of age by the industrial medicine departments of four big companies in the Paris region. The exploratory methods included prostate specific antigen (PSA) and prostatic acid phosphatase (PAP) assays, rectal palpation and two-dimensional transrectal ultrasonography. Biopsy of the prostate was performed either when the PSA level was above 5 ng/ml or when rectal palpation gave suspicious results, or when ultrasonography showed abnormal images. A total of 93 biopsies were performed, and 18 cases of cancer were detected. Eleven of these 18 patients underwent radical prostatectomy. The PSA assay, with an accepted limit of 5 ng/ml, detected 17 out of 18 cancers but was not very specific. The PAP assay had low sensitivity (only 5 positive results). Combined PAP assay and rectal palpation provided high sensitivity and good specificity. Transrectal ultrasonography was helpful only to determine the site of biopsy and the distribution of the lesions.

Acid Phosphatase↗