Biomedical subjects

E Séguier-Lipszyc

Publications and source records attributed to E Séguier-Lipszyc.

3 recordsLinked to original sources

PubMed2001

GDNF expression in Wilms tumor.

PURPOSE: Wilms tumor or nephroblastoma is a developmental tumor of the kidney and one of the most frequent solid tumors in childhood. It derives from metanephrotic blastema and mimics nephrogenesis in a disorganized manner, offering an adequate model for study of human nephrogenesis. GDNF (glial cell line derived neurotrophic factor), a potent proliferation and survival factor of dopaminergic neurons, has recently been shown to have an early and major role in nephrogenesis. We studied the expression of GDNF in Wilms tumor. MATERIALS AND METHODS: The study included 20 patients with nephroblastoma whose age at surgery ranged from 2 months to 13 years. Expression of GDNF protein was analyzed by an immunohistochemical technique using anti-GDNF antibody. Presence of GDNF-messenger (m)RNA and receptors GFRalpha1 and GFRalpha2-mRNA was analyzed by reverse transcription polymerase chain reaction. Specimens were also studied to evaluate apoptosis, proliferation index and Bcl-2 expression. RESULTS: GDNF expression was mainly found in the epithelial cells of the most differentiated tubes, GDNF and co-receptors mRNA were found in specimens and proliferative activity was found on the same tubes as GDNF expression. Bcl-2 was expressed strongly in epithelial cells, in an intermediate fashion in the blastema and faintly in mesenchyma. Apoptosis was of low frequency in structures strongly expressing GDNF. CONCLUSIONS: We have shown that GDNF is expressed by nephroblastoma tissue of human kidneys. This expression is mainly in the differentiated epithelial component of the nephroblastoma. We have also shown that tissue strongly expressing GDNF is positively proliferative and has less apoptotic activity. We speculate that the role of GDNF may not be limited to normal nephrogenesis but may interact with other factors in the process of proliferation and apoptosis involved in nephroblastoma tumorigenesis.

Adolescent↗

PubMed2001

The Mitrofanoff procedure: 20 years later.

PURPOSE: We review our initial cases of continent cystostomy to assess long-term functional results and complications after a minimum of 15 years of followup. MATERIALS AND METHODS: Between 1976 and 1984, 23 continent cystostomies were performed on 15 boys and 8 girls with neuropathic bladders. Mean patient age at surgery was 8 years and 4 months (range 3 to 16) and mean followup was 20 years (range 15 to 23). The neurological lesions were due to 21 myelomeningocele (2 associated with an imperforated anus in 21 cases), spinal neuroblastoma in 1 and complex genitourinary malformation associated with an imperforated anus in 1. Closure of the bladder neck was performed in 21 cases (16 during the same procedure, 5 secondarily) and 2 did not undergo this procedure. The appendix was used as the catheterizable conduit in 20 cases, 1 ureter in 2 and a bladder tube in 1. Bladder augmentation was performed during the same procedure in 2 cases and at a later stage in 8. Five patients presented with unilateral or bilateral secondary vesicoureteral reflux. RESULTS: One death occurred after conversion to cutaneous diversion due to a postoperative infection leading to a ventriculoperitoneal valve infection. The remaining 22 patients were followed every 6 to 12 months. No metabolic disorder, secondary malignancy or spontaneous bladder perforation was noted. Bilateral upper tract deterioration was found in 10 cases leading to secondary bladder augmentation by enterocystoplasty in 6 and creation of noncontinent diversion in 4. Leakage occurred after bladder neck closure in 5 patients. Bladder stones were found in 5 patients (2 had prior bladder augmentation). Complications related to the conduit included stomal stenosis or persistent leakage in 11 cases, which required surgical revision and/or repeated dilations and 1 noncontinent diversion after revision failure. Five patients presented with intestinal occlusion due to volvulus in 3 and adhesion in 2. We noted that after 10 years of followup complications were rare and concerned mostly the catheterizable conduit. Therefore, 16 patients had a good and stable result while 6 have noncontinent diversion. CONCLUSIONS: The rate of complications has a tendency to decrease with time. The results obtained in this series may appear less satisfactory than those of more recent series, which may be due to the fact that these oldest continent cystostomies correspond to acquisition of experience of this novel approach, and to a period when the concept of low pressure reservoir was not yet established and bladder augmentations were not routinely performed. Since 1984 no continent cystostomy performed at our institution was converted into a noncontinent diversion. This series with long followup demonstrates that continent cystostomy is a procedure with lasting efficiency.

Adolescent↗

PubMed2000

Elective laparoscopic cholecystectomy.

BACKGROUND: Gallbladder stones are very common in patients with sickle cell disease and are the cause of recurrent abdominal pain. Their management has been highly controversial, especially for children. Nonoperated patients and those treated on an emergency basis have a very high rate of morbidity (>50%). METHODS: We performed a retrospective review of a series of 29 homozygous SS sickle cell children who underwent laparoscopic cholecystectomy between 1991 and April 1998. RESULTS: Only in one case a conversion was necessary (early in the series). Exploration of the common bile duct was done via intraoperative cholangiography. There were no mortalities. The morbidity rate was 17%; (however, of the five patients concerned, four suffered from hyperthermia for 2 days. All of the children were improved and enjoyed resolution of their abdominal pain. CONCLUSIONS: We believe that elective laparoscopic cholecystectomy at the earliest time possible, along with correct perioperative management, is the treatment of choice for cholelithiasis in children with sickle cell disease.

Abdominal Pain↗