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Biomedical subjects

F Roussel

Publications and source records attributed to F Roussel.

54 records · Page 3Linked to original sources
PubMed1985

[Immunoperoxidase labelling of blood vessels by 3 lectins: Ulex europaeus I, Lotus tetragonolobus, Dolichos biflorus].

Ulex europaeus agglutinin I, revealed by an immunoperoxidase (PAP) reaction, marks strongly and uniformly, on usual preparations human endothelial cells and makes up one of the best methods to observe vascular network distribution. It defines a general type (UEA I positive, LTA and DBA negative) including most of normal and pathologic endothelial cells. Only three varieties of cells, usually named endothelial ones do not stain: they are liver and marrow sinusoidal cells and lymphatic endothelial cell.

Animals↗
PubMed1985

[Experimental colonic cancers].

An experimental model of colonic cancer can be obtained in rodents by administration of 1-2 Dimethylhydrazine. It produces constant, reproducible lesions, ranging from simple anomalies of secretion to invasive cancers, which are identical to those observed in man. It should be noted that the rats and mice used in these experiments do not present spontaneous colonic tumours. This model has contributed to the substitution of the polyp-cancer sequence by the dysplasia-cancer sequence. All of steps of malignant transformation of the mucosa can be followed by histochemistry of the mucins, by ultrastructural examination of the basement membrane and by labeling of the sub-epithelial connective tissue with hyaluronectin. In man, it is possible to define high risk lesions prior to the appearance of polyps.

1,2-Dimethylhydrazine↗
PubMed1984

[Chemoinduced early precancerous colonic lesions in rats].

The aim of this study was to investigate the early histological changes during 1.2-dimethylhydrazine-induced carcinogenesis in the rat, and to search for a dose-response relationship. Thirty Wistar female rats received 1.2-methylhydrazine 15 mg/kg sc, weekly in a single injection, and were sacrificed after 1 to 9 weeks. The left portion of the colon was cut serially (300-350 sections per animal) and was then submitted to a routine histochemical study with 18 stains. Loss of mucous secretion and apical basophilia lesions were observed as early as the 2nd week. The rate of apical basophilia lesions, expressed in percentage of the total number of lesions, was significantly correlated with the total dose of carcinogen administered (p less than 0.001). The severity of the lesions (expressed as the logarithm of the total number of sections showing altered tubes) increased with the dose, first quickly, then more slowly afterwards. A significant correlation was observed between the site, as defined by the distance from the anal verge and the severity of the injuries (p less than 0.001) as they were located more proximally as the doses increased. The comparison of the results obtained from this series of animals sacrificed early and those from a former series with spontaneous survival, suggests that only 2 p. 100 of the apical basophilia lesions should develop macroscopic lesions (polyps or cancers). Hence, it is advisable to consider the chronology and the site of the sampling in order to interpret apparently divergent series.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

[Morphologic parameters of sperm. 1) Syndromes].

In this study we have been able to pull out 23 case histories of husbands of sterile wives out of a total of 839 patients who consulted us for diminished fertility. These 23 have the characteristics of "normal" male male population and serve as a reference group to estimate normal values of different parameters. The steps taken in this way give figures that are very little different from those obtained by other methods but once a still larger group have been analysed it would be possible by this method to work out the incidence of the different pathological states that can be found in the general population. An analysis of the differences found in our groups shows that the most significant parameter is the percentage of spermatozoa that are moving in straight lines. This means that future efforts should be directed to this parameter when automation or standardization is considered. There are normally random fluctuations in the parameters of healthy subjects but pathological pressures in subjects with lowered fertility mean that some of them vary in parallel coordinated directions. Because of this, seven different profiles can be worked out for different syndromes: Where the head alone is affected: macrocephalic spermatozoa, broken spermatozoa. Where the intermediate portion alone is damaged: a very thin intermediate portion. Where the tail alone is affected: spermatozoa with a short or absent tail. Where several parts of the sperm are affected: hook-shaped spermatozoa, double-headed spermatozoa, and rolled-up spermatozoa.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1980

1-2 Dimethylhydrazine induced colonic tumours in rats.

1-2 dimethylhydrazine was injected subcutaneously on a weekly basis of 15 mg/kg, during periods ranging from one to twenty-eight weeks into five hundred Wistar rats. Glandular-mucin depletion appears as early as the second injection (sulfomucins disappear). From the sixth week, one observes dysplasia; if the animals are allowed to survive for a longer period all will develop colonic carcinomas, which were found mainly in the left colon. This dysplasia, which is first mild, then moderate, is finally severe in rat mucosa or in the area of polyps. Dysplastic polyps become less frequent when carcinomas increase in number and in size. The average length of survival after cessation of the exposure is inversely proportional to the total dose administered. The glandular mucin depletion-dysplasia-carcinoma sequence characterizes the types of formation of 1-2 DMH induced colonic carcinomas. One of the striking features is the early appearance of this sequence.

Animals↗
PubMed1979

[Tumor angiogenic activity (introductory note)].

Some classical experiments proving the existence of a Tumoral Angiogenic Factor are reproduced. They show the presence of T.A.F. in a solid tumor (Walker 256) and its apparent absence in a leukemia (L 1210). We point out that the biological activity oversteps the barrier of zoological class.

Angiogenesis Inducing Agents↗
PubMed1978

[Stages of carcinogenesis of experimental colonic tumors induced with 1-2 dimethylhydrazine].

The authors poisoned 500 female Wistar rats with a dialy dose of 15 mg/kg, The total dose ranged from 15 mg/kg to 420 mg/kg, according to the group. The animals were either killed when the dose defined for each group and been reached, or allowed to live. In a first series of 6 groups (120 animals), the following facts were noted: tumours deeveloped in all animals left alive, after 28 weeks (total dose of 1/2 D.M.H. = 420 MG/KG). Changes in the mucosa were seen from the 40th day on with, in the descending colon, a punctate abnormality involving two or three glandular tubes, in general at the summit of the folds. This abnormality consisted of basophilia of the upper part of the tubes, with a loss of mucus secretion. All transitional stages were seen between this lesion, hyperplasia of the apex of the tubes, the formation of "polyp seeds" and the appearance of polyps. Carcinomas most frequently developed in polyps but sometimes in flat mucosa. In the ascending colon, changes in mucosecretion were seen after a similar time delay at the base of the glandular crypts.

Animals↗
PubMedDate not supplied

Cost effectiveness of a medical digital library.

The rapid increase in the price of electronic journals has made the optimization of collection management an urgent task. As there is currently no standard procedure for the evaluation of this problem, we applied the Reading Factor (RF), an electronically computed indicator used for consultation of individual articles. The aim of our study was to assess the cost effective impact of modifications in our digital library (i.e. change of access from the Intranet to the Internet or change in editorial policy). The digital OVID library at Rouen University Hospital continues to be cost-effective in comparison with the interlibrary loan costs. Moreover, when electronic versions are offered alongside a limited amount of interlibrary loans, a reduction in library costs was observed.

Cost-Benefit Analysis↗
PubMedDate not supplied

Identification of human papillomavirus antigen in a bladder tumor.

Human papillomavirus (HPV) antigen was found in one of six noninfiltrating (grade II) carcinomas of the bladder. The antigen was located in the nuclei of the superficial cells. This virus-bearing tumor occurred in a patient with no known risk factors. The presence of HPV in low-grade urinary lesions seems to be frequent and may reflect the early stages of carcinogenesis; in fact, HPV infections may cause papillomas and carcinomas of the urothelial mucosae as well as the genital mucosae.

Antigens, Viral↗
PubMedDate not supplied

Fine needle aspiration of retroperitoneal human dirofilariasis with a pseudotumoral presentation.

The accidental finding of a pseudotumoral para-aortic mass in a 60-year-old woman led to the performance of a fine needle aspiration (FNA) biopsy under ultrasonographic guidance. The milky aspirate was centrifuged and processed as a cell block. The examination of sections confirmed the lymphatic origin of the sample, but also revealed some unexpected parasitic structures. While a complete identification could not be made on a few sections, the morphologic and epidemiologic evidence suggested Dirofilaria repens. The mass was surgically removed and identified as an adenolymphocele, which appears to be a new localization of dirofilariasis in humans. This case emphasizes the utility of FNA in diagnosing such unexpected findings without the use for exploratory surgery.

Animals↗
PubMedDate not supplied

Evaluation of large-needle biopsy for the diagnosis of cancer.

The arguments for a choice between a large or fine needle in the diagnosis of tumors are still unclear. This paper reviews the advantages and disadvantages of large-needle biopsy and fine needle aspiration. Reports indicate that although the procedures have the same diagnostic efficacy, the risk of tumor seeding is far higher following large-needle biopsy. For this reason it should be avoided for the diagnosis of cancer. The risk of tumor seeding after fine needle aspiration may be reduced by performance through a cover of normal parenchyma, by maintaining suction during withdrawal of the needle and by examining samples for quality during the procedure.

Abdominal Neoplasms↗