Search PubMed⌕ Search

Biomedical subjects

M O Bitker

Publications and source records attributed to M O Bitker.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Human papilloma virus infection and renal transplantation. Two personally observed cases and a review of the literature].

Two cases of recurrent genital infection due to human papilloma virus (HPV) infection with preneoplasic lesions were observed in kidney transplant recipients. The neoplasic component appears to be very frequent in this immunosuppressed population with a risk estimated at 7%. According to the different authors in the literature [correction of litterature], genital lesions due to HPV, with or without dysplasia are found in 15 to 30% of the transplant population. The factors of risk are not different from the general population and are a function of sexual activity. The clinical expression of the lesions, their clinical course and recurrence are probably related to the immunosuppressor treatment. All such patients should be carefully screened to allow prevention and treatment, which, as seen in these cases, may be insufficient to irradicate the lesions. New therapeutic approaches should be studied in this group of patients at risk.

Female↗
PubMed1994

Patterns of Epstein-Barr virus latent and replicative gene expression in Epstein-Barr virus B cell lymphoproliferative disorders after organ transplantation.

B cell lymphoproliferative disorders arising in organ transplant recipients (B cell posttransplant lymphoproliferative disorders [PTLD]) are generally associated with EBV. In previous reports, B cell PTLD were shown to express the full pattern of EBV latent genes, as in vitro-established lymphoblastoid cell lines. Although viral linear DNA was detected in 40% of lymphoproliferative disorders from immunocompromised hosts, immunophenotypic studies failed to detect late EBV replicative antigens. The aim of this study was to investigate the relationship of EBV latent gene expression in B cell PTLD to morphology, clonality, and immunophenotype, and to examine the replicative state of EBV in malignant cells. For this purpose, 9 cases of EBV-related B cell PTLD were analyzed. Immunoglobulin gene rearrangements were detected by Southern blot analysis. The presence of EBV was assessed by Southern blot and by in situ hybridization. B cell differentiation antigens, adhesion and activation molecules, and EBV latent and replicative gene expression were studied using immunohistochemistry techniques. We demonstrated that EBV-related B cell PTLD exhibited varying patterns of latent viral gene expression. Higher levels of adhesion molecules were detected in latent membrane protein 1 (LMP1) or LMP1 plus EBV nuclear antigen 2 (EBNA2)-positive tumors than in LMP1 and EBNA2-negative tumors. In contrast, there was no relationship between CD21 and CD23 expression and latent EBV phenotype. Activation of the EBV replicative cycle was highlighted by BamHI Z left frame 1 expression in 5 of 9 cases. Less frequent expression of late viral proteins suggested that the initiation of the EBV lytic cycle might not always lead to virions production.

Adult↗
PubMed1994

Prevention of acute cyclosporin nephrotoxicity by verapamil and atrial natriuretic factor in the rat.

Nephrotoxicity is the most common and important side-effect of cyclosporin (CsA) therapy. CsA alters renal haemodynamics with a reduction in renal blood flow (RBF) and glomerular filtration rate (GFR) and a significant increase in renal vascular resistances (RVR). The present experimental study investigates whether verapamil or atrial natriuretic factor (ANF) are able to prevent the nephrotoxicity of CsA. All studies were conducted in an in-situ autoperfused rat kidney model which allows continuous measurement of renal blood flow without dissection of the renal artery. CsA as a 40 mg/kg bolus dose significantly decreased RBF (from 2.15 +/- 0.1 and 2.19 +/- 0.1 before CsA, to 1.29 +/- 0.16 ml/min/100 g BW, 60 min after CsA administration) (P < 0.05), and GFR (from 0.14 +/- 0.1 and 0.13 +/- 0.01 before CsA, to 0.08 +/- 0.01 ml/min/100 g BW, 60 min after CsA administration) (P < 0.05). CsA significantly increased RVR (from 9.5 +/- 0.73 and 9.8 +/- 0.78 before CsA, to 16.7 +/- 2.9 mmHg x min/ml 60 min after CsA administration) (P < 0.05). Verapamil pretreatment (as continuous intrarenal infusion at the rate of 1.25 micrograms/kg/min) attenuated the fall in GFR (from 0.16 +/- 0.01 and 0.19 +/- 0.03 ml/min/100 g before CsA to 0.20 +/- 0.05 ml/min/100 g BW, 60 min after CsA administration) (NS) and in RBF (from 2.42 +/- 0.2 and 2.6 +/- 0.22 ml/min/100 g before CsA to 1.79 +/- 0.17 ml/min/100 g BW, 60 min after CsA administration (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Torsion of the spermatic cord. Current controversies].

The diagnosis of torsion of the spermatic pedicle is primarily clinical, despite the many studies concerning the value of complementary investigations. Currently available imaging modalities are limited either by their lack of sensitivity or by their lack of availability. The absence of well established evidence of direct impairment of contralateral testicular exocrine function is in favour of conservative treatment whenever the local conditions are suitable.

Humans↗
PubMed1994

Is overhydration in CAPD patients a contraindication to renal transplantation?

Over a 14 year period, 56 of 415 CAPD patients (34 male, 22 female), aged 42.7 +/- 11 years, underwent renal transplantation (TR). A cadaver kidney was used in 53 patients (kidney-pancreas in 2), and a human leucocyte antibody (HLA) identical related donor organ was used in 3. Underlying renal diseases were chronic glomerulonephritis in 30 patients, diabetic nephropathy in 10, interstitial nephropathy in 5, vascular in 4, polycystic kidney in 3, and undetermined in 4. Mean duration of CAPD prior to TR was 13 months (2-56 months). A three-week peritonitis episode-free interval was requested prior to TR. At year 1, actuarial patient and graft survival (96% and 86%, respectively), plasma creatinine, and number of rejection episodes were not different from those recorded in patients treated with hemodialysis (HD) prior to TR. At TR, pulmonary artery pressure (PAP) was elevated (average 21.1 +/- 7.4 mm Hg), > or = 25 mm Hg and > or = 30 mm Hg in 36% and 14.6% of CAPD patients, respectively. Post-TR, HD was performed in 4 patients; no peritoneal infection occurred. Postoperative sonography disclosed ascitis in 12.7% of CAPD patients. The PD catheter was removed two months post-TR. Hemodynamic findings at TR suggest a frequently underestimated overhydration in CAPD patients, which should be detected and treated in order to reduce acute cardiovascular complications at TR.

Adult↗
PubMed1994

[Prevalence of severe arterial hypertension in patients with renal grafts and surgical indications. Experience of the La Pitié Hospital].

Five hundred eighty five renal transplantations were performed in our group from January 1982 to December 1992. The observed incidence of hypertension in this group is 45%. Invasive treatment was indicated in 20 hypertensive patients (3.4%): 4 patients had bilateral-nephrectomy and 16 patients were treated for renal artery stenosis. This last group consisted of 12 men and 4 women (mean age of 36 years), who received a cadaveric transplant. 7 patients were hypertensive prior to transplantation. Only 25% of the patients received cyclosporine. Initial nephropathy was a glomerular in 9 cases. Before surgical treatment, an average of 3.2 anti-hypertensive drugs were necessary to control arterial pressure. Percutaneous transluminal angioplasty was indicated in 11 patients, whereas surgical correction of arterial stenosis was realized in 6 cases. Angioplasty was associated with poor results (persistent HTA and renal failure in 7 out of 11 patients). After surgery of renal artery, all patients had normal blood pressure. Renal artery stenosis would require surgical treatment, when possible. If not, percutaneous transluminal angioplasty will be proposed. The most efficient surgical procedure seems to be resection of the structure and termino-terminal anastomosis. When usable, internal iliac artery can be sutured beyond the stenosis.

Adult↗
PubMed1993

[Posterior vertical lumbar incision in the treatment of pyelo-ureteral junction anomaly: report of 71 cases].

Posterior vertical lumbar incision, described for the first time in 1869 by Simon, provides a simple access to the kidney and offers excellent exposure of the ureteropelvic junction. The technical modifications proposed by Gil Vernet facilitate access to the kidney and reduce the morbidity. The operative technique is described in detail and the authors report their retrospective experience of 71 cases of correction of ureteropelvic junction anomalies (stage 2, 3 and 4). The morbidity was low (19%). Patients returned to work by the 3rd week. 88% of good results were observed at 3 months (84% in initial stage and 4 lesions). This approach should be preferred to the lateral incision or the percutaneous approach due to the simplicity of the technique and the low complication rate.

Adolescent↗
PubMed1992

[Amplification of a circulating CD4+CD7- T lymphocytes subset in kidney transplantation].

A minor subset of CD4+ T-cells (10 +/- 4 percent) that does not express the CD7 antigen is detectable in normal individuals. These CD4+CD7- T-cells have lower proliferative capacities than autologous CD4+CD7- T-cells. We observed an expansion of CD4+CD7- peripheral T-cells in 45 kidney transplant recipients. The CD4+CD7- TL expansion (23 +/- 20 percent was observed in both short term (< 6 months, n = 20) and long term transplanted patients (> 3 years, n = 25). These results significantly differed from those observed in patients on dialysis (10 +/- 4 percent, P < 0.002). The percentages of CD4+CD7- TL in kidney recipients are significantly correlated with the percentages of CD4+CD57+ and CD8+CD57+ T-cells subsets. A three-color immunofluorescence analysis indicated that 75 percent of the CD4+CD7- TL express the CD57 molecule contrasting with those in normal individuals (0.3 percent). Purified CD4+CD7- T-cells from kidney recipients have lower proliferative responses after PHA, CD2 and CD3 stimulations than autologous CD4+CD7+ TL. The proliferative response is partially restored by the addition of anti-CD28 moAb or IL2. We have highlighted, in kidney recipients with good graft function, an expansion of CD4+CD7- T lymphocytes which could be associated with CD4+ T-cell anergy and tolerance.

Antigens, CD↗
PubMed1992

[Value of tomodensitometry with injection and late images for the diagnosis of urinary leaks in kidney transplants].

Between May 1985 and May 1990, 263 renal transplantations were performed in 254 patients, with 4 kidney-pancreas double grafts. 12 urinomas were observed, i.e. 4.56%. In one half of cases, clinical examination alone was able to establish the diagnosis of urinoma, but in the other 6 cases, complementary investigations were required. Post-contrast computed tomography with late images (between 6 and 24 hours after the injection) would appear to be the most useful investigation. Performed in 6 cases, this examination established the diagnosis of urinoma in 5 cases and also suggested the mechanism of the leak, which was always confirmed at operation. The positive diagnosis is based on extravasation of contrast agent which is clearly visible, even in the presence of low concentrations due to impaired renal function. This extravasation occurred early in 3 cases, but was delayed in 2 cases, emphasising the importance of late images. Other investigations appear to be less useful either because of a lack of sensitivity or because of imprecise anatomical information. The severity of urine leaks and the need for rapid treatment justify post-contrast computed tomography with late images in any case of suspected urinoma.

Adult↗