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Y Boivin

Publications and source records attributed to Y Boivin.

At least 19 recordsLinked to original sources
PubMed1994

Complex hyperplasia of the endometrium. Predictive value of curettage vs. hysterectomy specimens.

We reviewed 94 cases of complex endometrial hyperplasia (CH) with and without atypia to assess some of the clinical and pathologic changes observed on curettage and in hysterectomy specimens. Age, parity, height, weight and nomograms did not differ between CH with or without atypia, and CH associated with endometrial carcinoma. CH without atypia, however, predicted lesser degrees of malignancy as compared to CH with atypia. Progesterone or progestinlike treatment is indicated for CH without atypia along with endometrial monitoring, but CH with atypia necessitates diagnostic and therapeutic hysterectomy whenever fertility is not a priority.

Adult↗
PubMed1994

All histological types of primary human rhabdomyosarcoma express alpha-cardiac and not alpha-skeletal actin messenger RNA.

Eleven human primary rhabdomyosarcomas (RMSs), including all histological variants, were analyzed morphologically, immunohistochemically for intermediate filament proteins and actin isoforms, and by means of Northern blots with probes specific for total actin, alpha-skeletal (SK), alpha-cardiac (CARD), and alpha-smooth muscle actin messenger (m)RNAs. All tumors disclosed ultrastructural evidence of skeletal muscle features with terminal differentiation in three cases. The RMSs contained immunohistochemically the intermediate filament proteins vimentin and desmin and reacted positively with the alpha-sarcomeric actin antibody, which recognizes alpha-SK and alpha-CARD actin isoforms. All RMSs reacted with the total actin probe, recognizing at 2.1 kb cytoplasmic actin mRNAs and at 1.7 kb alpha-actin mRNAs. With the specific probes, all RMSs expressed alpha-CARD actin mRNA, four neoplasms expressed also alpha-smooth muscle actin mRNA, whereas the probe for alpha-SK actin mRNA never produced a signal except in one case, in which the tumor masses were intermingled with non-neoplastic preexistent striated muscle fibers. Because alpha-CARD and alpha-smooth muscle actins are transiently expressed during normal skeletal muscle development, RMSs seem to follow normal skeletal myogenesis without completing the final step, consisting of alpha-SK actin mRNA expression. The use of Northern blots for alpha-CARD actin as an adjunct to conventional techniques may be helpful for the precise identification of primary RMSs compared to other soft tissue neoplasms.

Actins↗
PubMed1992

Allocating human resources among the services of a health care organization.

The problem of optimizing the allocation of human resources among the services of a health organization is explored. The suggested approach borrows from normative budgeting models (ADVISOR) and product portfolio matrices to derive an allocation rule that seems to offer a reasonable rationale for eliminating certain services and reallocating the available resources to other services. The authors describe the approach and its implementation.

Budgets↗
PubMed1990

An assessment of the risk of neoplasia in long-term ileal reservoirs using the DMH rodent model.

This study was undertaken to determine if the construction of an ileal reservoir induces mucosal changes that can potentiate the effect of a chemical carcinogen (1,2-dimethylhydrazine) on ileal mucosa. Animals were divided into three groups: 1) sham operation (n = 19), 2) total colectomy with ileorectal anastomosis (n = 20), 3) total colectomy with an ileal reservoir made of terminal ileum sutured to the rectum (n = 20). An adaptation period of 12 weeks was allowed to promote fecal stasis and the histologic changes before exposure to weekly subcutaneous injections of DMH (25 mg/kg) for 16 weeks. Sodium butyrate was added to the diet as a tumor promotor. All animals were sacrificed one month later. Fecal stasis, along with enlargement, occurred in all the reservoirs (mean dimensions, 74 X 58 X 43 mm). Their mean volume was 88 +/- 14 ml. The histologic changes in the ileal reservoirs were: chronic inflammation (14/20), villous atrophy (14/20), and atrophy of the glands (8/20). In group 3, five carcinomas were seen. There were three in the duodenum and two in the reservoirs. In contrast, 21 carcinomas were detected in the control groups. There were 17 in the colon, 3 in the jejunum, and 1 in the ileum. No significant difference in the number of carcinomas was seen in the ileum with and without reservoir. Although it is possible to induce carcinomas in ileal reservoirs, the incidence remained significantly less than in the colon. In conclusion, the histologic changes induced by the construction of an ileal reservoir do not increase the risk of malignant transformation in the DMH model for intestinal carcinogenesis.

1,2-Dimethylhydrazine↗
PubMed1986

Assessment of validity of DNA measurement in tissue sections by model simulation.

Computer modelling is used to simulate nuclear segments obtained by random sectioning through tissue. A few more computations lead to DNA measurement simulation. Two methods of DNA measurement (a direct one and a variant of the "plug" method) are tested on simulated diploid, tetraploid and octaploid cell populations. The two methods result in negatively skewed DNA frequency distributions. Both the right skewness and the coefficient of variation of measurements are increasing with the ploidy level because nuclear DNA content is assumed to be related to nuclear size in the chosen model. Observed mean values are biased underestimates of expected values but are strongly correlated to the degree of ploidy. The variant of the "plug" method gives rise to smaller coefficients of variation. Finally, the bias introduced by measuring nuclear segments instead of whole nuclei increases the variance of measurements but contributes to less than half the experimentally observed variance. Our conclusion is that microspectrophotometry on tissue sections is a valuable method for DNA content evaluation of small clusters of pathological cells as one may find in endoscopic biopsies.

Cell Nucleus↗
PubMed1979

Computerized axial tomography and fine-needle biopsy in surgery of the pancreas.

Notable advances have been made in the investigation of pancreatic disorders. However, many of the diagnostic tests required are still of an invasive nature and are attended by difficulty and risk. The authors have found that the noninvasive method of axial tomography is highly reliable for the evaluation of pancreatic lesions, especially in cases in which a pancreatic mass is present or the duct of Wirsung is dilated. This procedure can also be helpful in the follow-up of patients who have suffered from acute or chronic pancreatitis. The same diagnostic problem is present at operation. To obtain a quick and reliable diagnosis of pancreatic lesions, the authors performed fineneedle aspiration biopsies followed by immediate staining and examination of the specimen. Among 43 patients an accurate diagnosis was obtained in 41 instances and no complication was ascribed to this diagnostic procedure.

Adenocarcinoma↗