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R Bouvier

Publications and source records attributed to R Bouvier.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Parenchymatous cicatrix and urinary tract infection: physiopathology and clinical implications].

Renal scarring is the main long term complication of acute pyelonephritis in children. The prevalence rate is hazardous since data from the literature are confusing with respect to reflux nephropathy, chronic pyelonephritis and renal hypoplasia. The pathology of such lesions consists in focal interstitial fibrosis. When the first pyelonephritic attack occurs during infancy, renal growth may be compromised. The current approach of renal scar assessment is based on dimercaptosuccinic acid (DMSA) scan. Bilateral extensive lesions may be responsible for altered glomerular filtration rate (GFR) and/or arterial hypertension. The management of overt scarring is conservative and careful prevention must be based on early and aggressive treatment of acute pyelonephritis.

Child↗
PubMed1998

[Unusual presentation of nephroblastomatosis].

BACKGROUND: Nephrogenic rests generally constitute precursor lesions of Wilms' tumor. We report a case of right nephroblastomatosis with dysmorphic features. CASE REPORT: An enlargement of the right kidney was incidentally discovered in a 1-year-old girl with dysmorphic features but normal psychomotor development. Combined ultrasonography and computerized tomography (CT) scan showed right cortical nephroblastomatosis. Chemotherapy using actinomycin D and vincristin was successful; however, an hyperechogenic nodule was subsequently found, necessitating a right nephrectomy. CONCLUSION: The relationship between nephroblastomatosis and Wilms' tumor is discussed. This case report reminds us of the importance of a long-term follow-up including echography and CT scan in cases of nephroblastomatosis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

[Preliminary results of the treatment of 44 patients with localized cancer of the prostate using transrectal focused ultrasound].

OBJECTIVE: To evaluate the efficacy and morbidity of treatment of localized prostatic cancer using transrectal high-intensity focused ultrasound. MATERIAL AND METHODS: 44 patients (mean age: 72 years) with clinical stage T1 (20) or T2 (24) prostatic cancer, not eligible for radical prostatectomy, were treated by two different prototypes of the Ablatherm (Technomed Medical System). The second prototype includes several safety devices designed to reduce morbidity. 99 sessions were performed, i.e. an average of 2.25 sessions per patient: the prostate was treated in one session (5 patients), 2 sessions (26 patients), 3 sessions (10 patients), or 4 sessions (3 patients), usually under spinal anaesthesia. The mean PSA was 9.92 ng/ml and the mean prostatic weight was 37 g. RESULTS: Complications occurred in 10 (50%) of the first 20 patients treated (1993-1995): 2 recto-urethral fistulas, 2 asymptomatic rectal burns, 2 cases of stable urinary retention, 1 case of severe incontinence, 3 cases of bladder neck sclerosis, and 1 febrile urinary tract infection. In the 24 patients treated subsequently (1995-1997), complications occurred in only 4 patients (16%): 1 case of stable urinary retention, 1 febrile urinary tract infection, 1 case of bladder neck sclerosis, 1 case of stress incontinence. A complete response (repeated negative follow-up biopsies) was obtained in 27 patients (61%). The mean post-treatment PSA level in patients of this group was 1.09 +/- 1.06 and remained stable (mean follow-up: 346 days; range: 60-1250). A residual cancer was detected in 17 patients (39%). 8 patients were considered to be failures (mean post-treatment PSA: 4.8 ng/ml) and received adjuvant treatment (hormonal: 3; external radiotherapy: 5). Complementary treatment by focused ultrasound will be performed in another 9 patients, if their PSA rises above 3 ng/ml (patients of this group are symptomatic with a mean post-treatment PSA of 1.6 ng/ml). CONCLUSION: The morbidity of treatment by transrectal focused ultrasound has now been reduced. These results suggest that this new treatment can constitute a useful option for certain patients with localized cancer, not suitable for radical prostatectomy.

Adenocarcinoma↗
PubMed1998

[Pseudotumor amylosis of the bladder. Apropos of a case].

A 57 year-old patient with localized pseudo-tumoral amyloidosis of bladder is described. There was no past medical history. Hematuria was the main symptom. The treatment consisted in transurethral resection. Two recurrences occurred at 4 and at 6 years which were also treated by resections. Clinical and biological evaluation was normal. Localized pseudo-tumoral amyloidosis of the urinary tract is a rare affection of good prognosis. Lesions present as pseudo-tumoral masses which can be biopsied without any risk of hematuria. Investigations are required to eliminate a generalized amyloidosis or a malignant lymphoproliferation. Treatment should be as conservative as possible.

Amyloidosis↗
PubMed1997

Autoradiographic distribution of brainstem substance P binding sites in humans: ontogenic study and relation to sudden infant death syndrome (SIDS).

The precise distribution of substance P (SP) binding sites in the human brainstem was investigated in normal cases (3 fetuses and 24 new-borns) and in 9 cases of Sudden Infant Death Syndrome (SIDS) by in vitro quantitative autoradiography. We discussed the widely but uneven distribution of SP binding sites as regards to the role of SP in brainstem cardio-respiratory ontogenic control and its possible involvement in SIDS.

Autoradiography↗
PubMed1997

Clinical relevance of TRKA expression on neuroblastoma: comparison with N-MYC amplification and CD44 expression.

TRKA expression was evaluated on 122 untreated neuroblastomas by immunohistochemistry using an antibody with predetermined specificity. This procedure is simple and reliable for protein detection at cellular level in a routine clinical setting. Fourteen tumours were classified as benign ganglioneuroma with a restricted expression of TRKA on ganglion cells; these patients were excluded from the following analysis. A total of 108 tumours were classified as neuroblastoma or ganglioneuroblastoma; 74 expressed TRKA protein, which strongly correlated with low stage, absence of N-MYC amplification, age (<1 year), CD44 expression and favourable clinical outcome. In a univariate analysis including tumour stage, age, histology, N-MYC amplification, CD44 and TRKA expression, all parameters had significant prognostic value. The absence of TRKA expression on CD44-positive or N-MYC non-amplified tumours permits the characterization of a subgroup of patients with intermediate prognosis. However, in a multivariate analysis taking into consideration the prognostic factors mentioned above, CD44 and tumour stage were the only independent prognostic factors for the prediction of patients' event-free survival.

Analysis of Variance↗
PubMed1997

Renal chromophobe cell carcinoma and oncocytoma. A comparative morphologic, histochemical, and immunohistochemical study of 124 cases.

BACKGROUND: Renal oncocytoma has several features that overlap with other renal neoplasms, including the eosinophilic subtype of chromophobe cell carcinoma. In fact, strict criteria for renal oncocytoma have not been well defined and remain a matter of controversy. Ultrastructural studies or sophisticated methods such as flow cytometry and cytogenetic techniques can be of great use in distinguishing the two tumors, but are difficult to propose as routine methods because of their limited availability. OBJECTIVE: To further characterize the histologic criteria of these tumors, we undertook a retrospective study to define the utility of routinely available histochemical and immunohistochemical techniques. DESIGN AND SETTING: Twenty-one cases of chromophobe cell carcinoma, eosinophilic subtype, and 103 cases of oncocytoma were tested with histochemical (Perls, periodic acid-Schiff, and Hale's colloidal iron) and immunohistochemical (peanut agglutinin antigen and UEA-1 for lectins; cytokeratin KL1, epithelial membrane antigen, vimentin, S100 protein, and lysozyme) staining. RESULTS: The antibodies tested and the histochemical staining using Hale's colloidal iron allowed eosinophilic chromophobe cell carcinoma to be distinguished by its characteristic reaction pattern. Seventy-six percent of the chromophobe cell carcinomas showed a microvacuolated pattern, and 89% of the renal oncocytomas showed an apical positivity with Hale's colloidal iron staining (P < .01). Peripheral cell accentuation reactivity for cytokeratin KL1 was observed in 66% of the chromophobe cell carcinoma cases, and apical cytoplasmic positivity was observed in 37% of the renal oncocytoma cases (P = .01). Significant patterns were observed with anti-epithelial membrane antigen and anti-peanut agglutinin antigen antibodies (P = .05 and P = .01, respectively). Positive reactions for vimentin, S100 protein, lysozyme, and UEA-1 were not significant characteristics. CONCLUSION: Our study demonstrated that a precise morphologic description associated with simple histochemical and immunohistochemical techniques provides sufficient criteria for a high level of discrimination between the eosinophilic subtype of chromophobe cell carcinoma and renal oncocytoma.

Adenocarcinoma↗
PubMed1997

[Glomerulopathy and hypomelanosis of Ito].

Hypomelanosis of Ito is a rare neuroectodermal syndrome characterized by specific cutaneous lesions and frequent musculoskeletal or visceral involvement. We report on a child with an original nephritis with major segmental abnormalities of the glomerular basement membrane. Such an association might not be fortuitous and glomerular involvement might be underestimated in hypomelanosis of Ito.

Basement Membrane↗
PubMed1997

[Diagnosis of lysosomal storage diseases with fetal presentation].

In metabolic diseases with fetal presentation, lysosomal storage disorders represent a fairly homogeneous group. Hydrops fetalis or ascites is the main but non specific symptom. The relative frequency of lysosomal storage diseases in this context is not well known and probably underestimated. They represent 1.4% in a large retrospective series. The contribution of the placental and fetal examination in their diagnosis is emphasized. The biological investigations required for their accurate pre and postnatal diagnosis are described. The precise identification of the lysosomal defect is necessary to propose an early prenatal diagnosis by chorionic villi biopsy in further pregnancies.

Fetus↗
PubMed1996

Correlations of allelic imbalance of chromosome 14 with adverse prognostic parameters in 148 renal cell carcinomas.

To investigate cumulative genetic alterations during development and progression of renal cell carcinoma (RCC), we examined DNAs that were isolated from 148 RCCs for allelic imbalance (AI) at four loci on chromosome arm 3p and at 26 loci on chromosome arm 14q by using polymorphic microsatellite markers and densitometric scanning. Because the analysis of solid tumor unbalanced rearrangements remains difficult due to the large proportion of cells that infiltrate from the stroma, we developed a method for the detection and quantification of AI between control and tumor samples by using polymerase chain reaction (PCR) amplification of microsatellite markers. This technique allows detection down to 20% of contaminating cells with good accuracy. We detected AI on 3p and 14q in 57 and 28% of RCC, respectively. A comparison of genetic changes with clinicopathological data showed that, in marked contrast to AI on 3p, AI on 14q was correlated significantly with the stage and grade of the tumors, with 56 and 58% of RCC in Stage IV and Grade 4, respectively, showing AI. Our results suggest that tumor suppressor genes on 3p, including the von Hippel-Lindau gene, may be involved in early steps of carcinogenesis in clear cell carcinoma and that AI on 14q may play an important role in the progression of clear cell and papillary chromophilic cell carcinomas. Loss of heterozygosity (LOH) on 14q may be a new prognostic factor in RCC. Despite the size of the series of tumors and the number of markers used, only rearrangements that involved the whole length of the long arm of chromosome 14 were observed in the present study. The localization of the putative tumor suppressor gene on 14q will require further investigation of RCC with structural rearrangements of 14q.

Adult↗
PubMed1996

Assessment of the bone mineral density in the lumbar vertebrae of newborns by quantitative computed tomography.

OBJECTIVE: To assess the true mineral density (BMD, in g/cm3) of the lumbar spine in newborns. DESIGN AND PATIENTS: A postmortem analysis of five infants with gestational ages ranging from 35 to 40 weeks, and birth weights from 2765 to 3200 g, was conducted using dual-energy quantitative computed tomography (QCT; Siemens Somatom DR). A 2 or 4 mm thick slice was obtained for each lumbar vertebra from L1 to L4. The density measured in these vertebrae was corrected by reference to a solid phantom (Osteo-CT) measured simultaneously. A three-dimensional image of the spine (Elscint CT Twin), as well as a photomicrograph of histological preparation from L2 vertebra, were also obtained in another term baby for comparison with the CT results. RESULTS AND CONCLUSIONS: In the range of values studied, the vertebral densities were not dependent on birth weight. BMD values measured in L2, L3 and L4 were not significantly different, but were 10% lower than in L1 in four of five infants. The spatial resolution of the QCT protocol used (0.4 mm) did not permit the differentiation of trabecular and cortical bone, and the vertebral bodies appeared very homogeneous and dense, with a mean density value of 210 +/- 30 mg Ca/cm3, which is 2.5 times higher than the mean maximum value found in young normal adults. These preliminary results highlight the potential of QCT in neonatology. Special protocols will, however, need to be developed for in vivo measurements in this particular paediatric field.

Absorptiometry, Photon↗
PubMed1996

Absence of correlation between reg and insulin gene expression in pancreas during fetal development.

The reg gene characterized in the exocrine pancreas has been found to be expressed in regenerating islets of 90% depancreatized rats and not in normal islets. In humans, it was identified only in the exocrine pancreas. Because the reg protein has been found to be related to islet cell replication and/or beta cell regeneration, we compared the expression of the reg gene with that of chymotrypsinogen of exocrine origin and insulin of endocrine origin. We investigated the expression of the three pancreatic genes in the fetal pancreas during human development using dot-blot analysis. The levels of expression of the corresponding mRNAs did not appear to undergo great changes between the 17th and the 29th wk of gestation. Nevertheless, the fetal mRNA levels for reg and chymotrypsinogen were below that of the adult, with very low levels of reg gene expression in more than half of the studied pancreases. In contrast, the insulin mRNA levels were significantly higher in fetal than in adult pancreases, suggesting that insulin may function as a growth factor during fetal development. Our results indicate that no correlation between reg and insulin gene expression exists in the fetal pancreas during the developmental period studied but, on the contrary, such a correlation was present in the adult pancreas.

Adult↗
PubMed1996

Treatment of prostate cancer with transrectal focused ultrasound: early clinical experience.

OBJECTIVES: To evaluate the efficacy of transrectal focused ultrasound on localized prostatic cancer. METHODS: Fourteen patients (mean age 72.5 years) with clinical stage T1 (3) and T2 (11) prostatic cancers, who were not suitable candidates for surgery were treated. The mean PSA pretreatment level was 12 +/- 10 ng/ml (Hybritech). The device used (Ablatherm, Technomed M.S.) combines a 2.25-MHz therapy transducer and a 7.5-MHz transrectal biplane ultrasound scanner probe (linked to a software enabling the operator to determine precisely the zone of the prostate to be treated. The prostate was treated in one (3 patients), two (7 patients) or three sessions (4 patients) under spinal (25 sessions) or general anesthesia (4 sessions). RESULTS: Complications occurred in 9 of the 14 patients (64%): early complications occurred in 6 (rectal burns 3, urinary retention 2, transient incontinence 1) and late complications in 5 (incontinence 2, bladder neck stenosis 3). The median PSA NADIR value (1.79 +/- 2.35 ng/ml) was achieved at 6 months and the final PSA value was 2.94 +/- 3.27 ng/ml (mean follow-up 380 days). Control biopsies demonstrated coagulative necrotic lesions of the treated prostate zones with secondary development into fibrosis. No residual cancer was observed in 7 patients after several random sextant biopsies. Residual cancer was found in 7 patients: 4 required complementary treatment (orchidectomy 2, external beam radiation therapy 2). Adjuvant therapy was deferred in 3 patients with stable PSA values under 2 ng/ml. CONCLUSIONS: A satisfactory local control with negative control biopsies was achieved in 50% of the cases in this pilot study. However, this therapy is an investigational procedure: long-term follow-up will be necessary to confirm these early results.

Aged↗
PubMed1996

Surgical management of complex renal cysts: a series of 32 cases.

PURPOSE: The differentiation between benign cysts of the kidney and those that require surgical exploration remains difficult. The accuracy of radiological techniques (ultrasound, computerized tomography [CT], angiography, magnetic resonance imaging, cyst puncture and intraoperative pathological examination) is analyzed. MATERIALS AND METHODS: Surgical exploration was performed in 30 patients with 32 asymptomatic renal cysts, and the pathological specimens were compared retrospectively to the radiological findings. The classification of Bosnaik was used to categorize the ultrasound and CT findings. RESULTS: Of our complex renal cysts 41% proved to be malignant. Our results suggest that the radiological techniques are not well suited for characterization of these cysts. None of the Bosnaik types was sufficiently predictive of the lesion. Only a Bosnaik score of 4 (the sum of ultrasound and CT Bosnaik types) was not associated with renal cell carcinoma. According to the radiological findings, 1 patient was under treated (recurrent renal cell carcinoma) and 4 were over treated (radical nephrectomy for benign lesions). CONCLUSIONS: A practical therapeutic strategy is described in which radical nephrectomy is performed when malignant lesions are detected either by preoperative or intraoperative techniques. Conservative surgery is indicated for benign cysts according to the clinical status and risks of nephron sparing surgery.

Adult↗