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P Chevallier

Publications and source records attributed to P Chevallier.

At least 109 records · Page 6Linked to original sources
PubMed1990

Spontaneous prolactin transplantable tumor in the Wistar/Furth rat (SMtTW): a new animal model of human prolactinoma.

Two spontaneous prolactinomas, removed from 28-mo-old female Wistar/Furth rats, were grafted by serial passages under the kidney capsule and the skin in 117 females of the same consanguineous strain. The hosts, aged between 2 and 10 mo, were free of estrogen treatment. These transplantable tumors, named SMtTW1 and SMtTW2, were studied until the fifth serial passage. The percentage of success was 100% under the kidney capsule and 20% under the skin. From the radioimmunoassays of prolactin (PRL), growth hormone, and adrenocorticotropic hormone and the immunocytochemical results, the tumors secrete PRL only. The PRL tumoral secretion was detected after 3 to 5 mo of graft; at 8 mo, mean plasma PRL values reached 5150 ng/ml (normal value, 15.2 ng/ml). Plasma growth hormone and adrenocorticotropic hormone values remained normal. Like the primary tumors, the grafted tumors were benign, grew slowly, and were sparsely granulated well-differentiated prolactinomas with exocytosis. They remained identical during the first serial passages. The secretion and the growth of SMtTW2 were inhibited by bromocriptine. In the light of our knowledge of the human prolactinoma, the spontaneous transplantable prolactinoma of the rat may be considered to be an animal model closer to the human pathology than the estrogen-induced "tumors" and the induced transplantable tumors. It is easier to use than the spontaneous prolactinoma of the rat.

Animals↗
PubMed1990

Early and frequent detection of HBxAg and/or anti-HBx in hepatitis B virus infection.

To clarify the significance of the X gene of hepatitis B virus, we have tested for anti-HBx in the serum and HBxAg in the liver at different stages of the natural history of hepatitis B virus infection. Sera were screened by enzyme-linked immunosorbent assay and positive results confirmed by immunoblot. Purified recombinant MS2 Pol-HBx fusion protein was used as target for both assays. Among serial sera of patients with nonfulminant acute hepatitis, 24 of 64 patients (37.5%) were positive for anti-HBx. In fulminant cases, 15 of 36 patients (42%) had anti-HBx. In chronic hepatitis patients with high rates of hepatitis B virus replication, we found a significantly (p less than 0.01) higher prevalence of anti-HBx, 14 of 25 patients (56%), than in those with low replication, 14 of 66 patients (21%), or among asymptomatic HBsAg carrier blood donors (20 of 126 = 16%) without detectable hepatitis B virus replication (p less than 0.0001). The highest prevalence of anti-HBx was found in HBsAg carriers with cirrhosis (41 of 54 patients = 76%) and/or with hepatocellular carcinoma (18 of 33 patients = 54%). The findings suggest that anti-HBx appears as a common and early marker of hepatitis B virus infection, transient in self-limited hepatitis but persisting with progression to chronicity. In chronic hepatitis, the prevalence of anti-HBx correlated with the intensity and duration of hepatitis B virus replication but neither with the severity of the liver disease nor with malignant transformation per se.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1990

Possible prevention of chronic hepatitis B by early interferon therapy.

A study is currently underway to investigate the efficacy of interferon therapy in patients with prolonged (greater than or equal to 10 weeks but less than 6 months) hepatitis B infection. To date, a total of 15 patients have been enrolled in the study and randomly assigned to receive either placebo for 24 weeks (n = 8) or interferon 5 million units subcutaneously 3 times a week for 24 weeks (n = 7), with follow up for 1 year. Thirteen patients have completed the follow-up period: seven patients in the placebo group and six in the treated group. Five of the six treated patients completely eradicated the infection during interferon therapy, with clearance of hepatitis B e and surface antigens, and seroconversion to antibody positivity in each case. Two of the eight placebo patients seroconverted during the placebo period. Clearance of hepatitis B e antigen was associated with a sudden rise in serum transaminase levels and an exacerbation of hepatitis, a phenomenon that has also been reported in chronic hepatitis B patients who have responded well to interferon therapy. Therapy was well tolerated in all cases. Our results suggest that interferon treatment of patients with prolonged hepatitis B infection may prevent progression to chronicity. If confirmed by further study, they should trigger more vigilant screening for patients with raised serum transaminase levels and viral markers of hepatitis B infection.

Base Sequence↗
PubMed1989

[Prevalence and socio-demographic factors].

From the results of 25 epidemiological studies, most of which were Anglo-Saxon and Scandinavial, the socio-demographic profile of children and teenagers having problems is evaluated and compared to that of French patients seeking treatment. It appears that most of the socio-demographic variables are discriminatory in child psychiatry but not in a regular way for the prevalence of it and for undertaking treatment. But, to go from observing a covariation between a socio-demographic trait and a state of mental health to identifying a risk factor requires specifying the nature and the meaning of the relationship and trying to understand the mechanisms involved.

Adolescent↗
PubMed1989

[Epidemiology of the resistance to antibiotics at the Hospital Center of Aulnay-sous-Bois].

Over the 14 month period (1/6/87-1/8/88) the majority of the bacteremia observed in the intensive unit (C.H. d'Aulnay) was due to Gram-positive bacteria (16/23 cases). The incidence of resistant to methicillin Staphylococcus aureus (SAMR) in blood culture was 10% in 1986 and 14% in 1987. Resistance of S. pneumoniae to penicillin was not detected; 30% of the 72 strains were resistant to erythromycin and 26% to tetracycline. Among Enterobacteriaceae, third generation cephalosporin is uncommon (2.8%) as gentamicin resistance (4.5%). Among the anaerobes, 57% of non Bacteroides fragilis group are resistant to penicillin. Nitroimidazole resistance was not detected.

Cross Infection↗
PubMed1986

Therapeutic activity of vidarabine in symptomatic chronic active hepatitis related to HBV.

The potential inhibitory effects of nucleoside analogues such as ARA-A and acyclovir on HBV-DNA-polymerase were first demonstrated in vitro and then confirmed in vivo in open dose finding studies. The therapeutic efficacy of both ARA-A and ARA-AMP which appeared the most potent drugs was then confirmed by various studies in symptomatic HBeAg-positive patients. These studies demonstrated a similar benefit of therapy with 38 and 40% of treated patients given ARA-A and ARA-AMP, respectively, who permanently cleared HBV replication after a single course, and 67-80% who did so after two courses. Significant improvement in transaminases and histologic activity was also documented (P less than 0.001). Myalgias were observed in 10 and 30% of the patients, respectively. Patients who failed to respond to nucleosides, and those coinfected with HDV, were treated with interferons. Out of 8 cases of HDV/CAH given 5 MU thrice weekly of fibroblast beta-interferon (UPSA) for 3 months, DNA-p activity fell transiently in all 6 initially elevated cases. A parallel decrease in anti-HD titers (P less than or equal to 0.05), inflammation (P less than or equal to 0.001) and necrosis (P less than or equal to 0.05) were observed. alpha-Recombinant interferon was given i.m. for 4 months (2-7 MU/m2 X 2/7 days) to 10 CAH with high DNA-p values. HBV replication was permanently inhibited in 4 cases and dramatically reduced in 3 additional patients. Three failed to respond. Careful monitoring of DNA-p values appeared to be the single most important factor in assessing activity.

Clinical Trials as Topic↗
PubMed1986

[Eradication of hepatitis B in dialysed patients through repeated sero vaccinations].

From December 1981 to April 1984, 56 dialysed patients have been enrolled in a sero-vaccination program in which injections of Hevac B vaccine and anti-HBs immunoglobulin have been repeated to obtain anti-HBs response. Anti-HBs antibodies were distinguished from passively transmitted anti-HBs whenever anti-HBs levels above 33 mUI/ml were found 60 days after the last injection of hepatitis B immune globulins (4 ml). Among 39 patients (25 men, 14 women) (mean age 59 years) the proportion of vaccine responders was 44%, 67%, 82%, 90% after respectively 4, 6, 10, 14 injections of Hevac B vaccine. Age, male sex and duration of dialysis were found to decrease the immune response to the vaccine. Multiple injections and maintenance of protective anti-HBs (titer greater than 20 mUI/ml) can be considered as the most effective method to eradicate HBV infection from dialysis centers.

Adult↗
PubMed1986

[Epidemiology of acute hepatitis among outpatients in the urban community of Lyon, 1983].

We conducted in 1983 an hepatitis surveillance programme in collaboration with 93% of the medical analysis laboratories in Lyons' urban area (1,100,000 inhabitants) and diagnosed 1,002 cases of acute hepatitis (incidence : 90.5 cases/10(5) inhabitants; HAV : 50.4 cases/10(5) inhabitants; HBV : 12 cases/10(5) inhabitants; non A non B : 24 cases/10(5) inhabitants; drugs : 4.2 cases/10(5) inhabitants). HBs Ag was undetectable in 12% of acute hepatitis B. Hepatitis A accounted for 91% of children's cases and 48% of cases among adults between 20 and 40 years old. Epidemics were observed among children after summer holidays related to the return of migrants from trips to their native country. For acute hepatitis B and non A non B, classical epidemiological data were observed, but the prevalence of drug addicts and homosexuals was low.

Adult↗