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Biomedical subjects

G Richer

Publications and source records attributed to G Richer.

At least 37 records · Page 2Linked to original sources
PubMed1980

Hyperglobulinemia in alcoholic cirrhosis. Relationship with portal hypertension and intrahepatic portal-systemic shunting as assessed by Kupffer cell uptake.

The relative importance of portal hypertension and intrahepatic portal-systemic shunting in the pathogenesis of hyperglobulinemia is examined in 31 alcoholic cirrhotic patients and 6 patients with idiopathic portal hypertension. The degree of portal hypertension was evaluated by combined umbilicoportal and hepatic vein catheterization and the intrahepatic portal-systemic hunting was assessed by the Kupffer uptake of [125I]albumin microaggregates during a single passage through the liver. All patients had comparable severe portal hypertension and most had bled from ruptured varices; however, no demonstrable relationship could be found between portal hypertension and hyperglobulinemia. Elevated levels of serum gammaglobulins and immunoglobulins (mainly IgG) were observed only in cirrhotic patients, particularly those with markedly altered Kupffer cell uptake. It is concluded that intrahepatic portal systemic shunting as evaluated by the Kupffer cell uptake is more important than the collateral circulation secondary to portal hypertension in the pathogenesis of hyperglobulinemia in alcoholic cirrhotic patients.

Adult↗
PubMed1980

alpha-1-Antitrypsin phenotypes in French Canadian newborns.

Cord blood sera from 390 French Canadian babies born consecutively in a Montreal hospital were phenotyped for alpha 1-antitrypsin. As in other populations, Pi M was the most frequent allele. The second most frequent was Pi S (0.0923). This Pi S allele frequency is significantly different from that of other Canadians, but similar to that of Normans and Bretons.

Canada↗
PubMed1980

[Stereological analysis of normal Papio Papio liver parenchymal cells (author's transl)].

Stereological analysis of normal Papio Papio liver parenchymal cells has been performed according to the method of Weibel (1969). The study was carried out on liver samples collected from 3 males and 3 females. Sampling was done at three levels of magnification (X 250, X 5 000, X 15 000) without taking into consideration the lobular variations. The lobular stereological model included the hepatocyte, all the cellular organelles and the extra-hepatocytic space compartment. Surface and volume densities were determined; the results are given with respect to three reference units : 1 cm3 lobular tissue, 1 cm3 hepatocyte and 1 cm3 hepatocytic cytoplasm. The mean volume of the Baboon hepatocyte and its components were also measured. Statistical analysis of the results did not show wide individual variation in the population studied. The volume densities of the components were compared to those of rat, dog and man as determined by other investigators. The hepatocytes constitute 84,9% of the lobular volume, and the extra-hepatocytic space 15,1%. The mean individual volume of the hepatocyte is 6 470 micrometer3, which is higher than in rat and dog. The smooth endoplasmic reticulum has a much higher surface density (3,93 m2/cm3) than that of the rough endoplasmic reticulum (1,53 m2/cm3). The values obtained in the present study can be used as reference values in the evaluation of experimentally induced hepatic modifications in Baboon.

Animals↗
PubMed1980

A medulloblastoma in a baboon (Papio papio).

A transitional medulloblastoma was found in the cerebellum of a young female baboon. The primary lesion that permitted its discovery was papillary and retinal edema in the peripapillary zone.

Animals↗
PubMed1978

[The mammary gland of the male rat: a histological, histochemical and ultramicroscopic study (author's transl)].

Results of a histological, histochemical and ultramicroscopic study of samples taken from the mammary glands of male Wistar, Sprague-Dawley and Long Evans untreated rats, aged about 8 weeks, are reported. Lobulo-alveolar epithelial formations were observed together with increased metabolic and secretory activity, more frequent in Wistar rats than in other strains. No visible morphological abnormality was noted in the genital tract or adenohypophysis. There was no sign of feminization. The same findings were observed in male Wistar and Sprague-Dawley rats given three different diets of which one was semi-synthetic. The possibility of an exogenous mammotropic dietary factor is therefore very improbable. Endogenous hormonal stimulation, especially consecutive increases in oestrogens and prolactin in the prepubertal period, is possibly the cause of development of mammary tissue. These results show that the mammary gland, in the normal male rat, is not inactive. It seems, therefore, that this organ is not a suitable model for the evaluation of experimental mammotropic effects.

Animals↗
PubMed1977

Difference in the distribution of e antigen among different ethnic groups in a population of blood donors.

Sensitive techniques were used to detect e antigen and the corresponding antibody (anti-e) among 368 voluntary blood donors positive for hepatitis B surface antigen in the Montreal area and 310 people living in close contact with them. Neither e nor anti-e was found in the absence of markers of hepatitis B virus (HBV). Among the blood donors e antigen was detected in 23 and anti-e in 313, and 32 were negative for both markers. Of the 368 blood donors 330 were of French origin and 38 from other ethnic groups. The 23 e-positive subjects were unequally distributed among the ethnic groups: only 14 (4.2%) were recruited among the French group while 9 (23.7%) were recruited among other ethnic groups (P less than 0.001). This differences among ethnic groups might be related to the vertical or horizontal mode of dissemination of HBV infection.

Antigens↗
PubMed1976

Chronic carriers of hepatitis B antigen (HBsAg). Histological, biochemical, and immunological findings in 31 voluntary blood donors.

Among 289 HBsAg carriers detected by the Montreal Red Cross Blood Transfusion Service and seen by our group, 31 submitted voluntarily to liver biopsy. These 31 carriers have now been followed for 10-33 months (mean: 23) and all remained positive for HBsAg. 15 of these 31 subjects had lived in institutions during infancy or childhood and none were drug users. Histological examinations revealed 24 cases of chronic persistent hepatitis (CPH), 2 cases of chronic aggressive hepatitis, 2 with steatosis, and 3 with normal liver. On repeated determination, 16 of the 31 subjects had at least one elevated transaminase level. Transaminases levels could not be correlated with the histological diagnosis. 4 cases had positive antinuclear antibodies, all in the CPH group, a finding that could not be correlated with any clinical, biological, or histological findings. The search for other autoantibodies and the immunoglobulin determinations were totally unrewarding. Thus, it appears that chronic HBsAg carriers in Montreal voluntary blood donors often have chronic hepatitis, usually persistent, occasionally aggressive; liver biopsy still remains the most useful approach in the evaluation of these HBsAg carriers. The HBsAg-carrier state seems to be well tolerated, but further long-term studies are needed to understand the natural history of this condition.

Adolescent↗
PubMed1976

Detection of surface and core antigens of hepatitis B virus in the liver of 164 human subjects. A study by immunoperoxidase and orcein staining.

The surface (HBsAg) and core (HBcAg) antigens of hepatitis B virus (HBV) have been searched by optic microscopy in the liver specimens from patients hospitalized for various conditions and from 38 HGsAg chronic carriers. The study was done blindly using Shikata et al.'s orcein staining on fixed and frozen material and direct immunoperoxidase on frozen material with antisera specific for surface (anti-HBs) and core (anti-HBc) antigens of HBV. No liver staining could be found in the 98 HBsAg seronegative patients. Among the 28 HBsAg seropositive patients, only 3 showed positive staining: 1 patient with acute viral hepatitis showed nuclear staining with anti-HBc; 2 patients with postnecrotic cirrhosis showed cytoplasmic staining with anti-HBs and/or orcein, and one of them also showed nuclear staining with anti-HBc. In contrast, among the 38 chronic carriers, 25 showed positive cytoplasmic staining with anti-HBs and/or orcein, while one of them (with chronic aggressive hepatitis) also showed nuclear staining with anti-HBc. Anti-HBs and orcein staining are equally sensitive and specific for the detection of HBsAg in hepatocytes; discrepant results can be attributed to sampling error of distribution of HBsAg in small liver fragments.

Hepatitis B Antigens↗
PubMed1975

Hepatitis B antigen in Montréal blood donors: childhood institutionalization as an epidemiologic factor.

In 1971 the Canadian Red Cross blood tranfusion service instituted routine screening for HBAg of all blood donors, using nationwide a standardized counterimmunoelectrophoretic technique. The prevalence of carriers in the Province of Québec is unusually high (0.51%), being 3 to 12 times higher than in the other nine provinces. Among the carriers found in the Montréal area 289 volunteered to be seen by our group for an extensive interview and a series of laboratory tests. There were 243 men and 46 women; their ages ranged from 18 to 55, 90% being less than 40. Twenty-nine were of foreign origin and 260 were born in Canada. The epidemiologic data revealed that the reservoir of HBAg carriers among the blood donors of the Montréal area was found predominantly in the autochthonous population of French origin. Moreover, it appeared that 149 (52%) had lived in institution when they were infants or children: 127 were orphans and had been placed in institutions as newborns or babies, and 22 others had lived in institutions for at least 1 year between the ages of 5 and 10. This was by far the most important single epidemiologic factor that could contribute to the explanation of the abnormally high prevalence of HBAg carriers in the population studied.

Adolescent↗