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Biomedical subjects

L Thiry

Publications and source records attributed to L Thiry.

At least 55 records · Page 3Linked to original sources

Mason-Pfizer like virus in kidney grafted patients.

Lymphocytes from a kidney grafted patient were specifically stimulated to incorporated thymidine in vitro by mitomycin C treated Hela cells infected with a Mason-Pfizer like virus (MPV). The thermolabile mutant of vesicular stomatitis virus (VSV tl) grown in leukocytes of this patient produced pseudotypes which were neutralized by the patient's sera and boy rabbit anti-MPV sera. Coculture of the patients leukocytes with SIRC cells yielded virus populations with dual properties; those of MPV plus those of another virus which was not typed serologically but possessed the biological properties of typical C particles. The patient also had neutralizing antibodies to MPV, which were detected by inhibition of syncytium formation on KC cells and by neutralization of VSV tl (MPV) pseudotypes. Preliminary results on the frequency of similar findings in other kidney grafted patients are presented.

Animals↗

Liver disease in patients undergoing hemodialysis and kidney transplantation.

Liver dysfunction was observed in 33% of patients treated by hemodialysis and kidney transplantation. Fifty-eight percent of these cases of hepatitis occurred in patients with past or present HBs antigenemia, and 77% of HBsAg-positive patients showed evidence of LD. However, during the course of a program conducted from 1969 to 1976 and involving 267 patients, the decrease in the prevalence of HBs antigenemia observed during the last two years did not lead to any reduction in LD incidence. In a small number of patients, potentially hepatotoxic drugs could be incriminated, but in our experience azathioprine never appeared to be involved. In a few patients, LD was due to granulomatous disease of the liver, such as tuberculosis and schistosomiasis. Twenty-one (7%) of the 267 patients at risk developed chronic hepatitis, which contributed to death in nine patients. In 12 cases (three deaths), this form of hepatitis occurred in HBsAg-positive patients, and in nine cases (six deaths), in HBsAg-negative patients. In three of these latter individuals, cytomegalovirus could be incriminated. Routine monthly screening for CMV in kidney recipients confirmed the high incidence of this viral infection in such patients. Studies on murine CMV infection have demonstrated that this infection can be enhanced by histoincompatible graft or by cyclophosphamide in a model that is very close to the kidney recipient. As in mice, CMV infection in kidney recipients apparently results from reactivation of a latent infection. It seems to play a major role in the LD observed and could apparently lead to chronic hepatitis and even to cirrhosis of the liver. Finally, the occurrence of LD in HBsAg-, anti-HBs- and antiCMV-negative patients would suggest the responsibility of other viruses for the pathogenesis of liver disease in patients treated by hemodialysis and kidney transplantation. Besides Epstein-Barr virus, other viruses, such as hepatitis C virus, should be thoroughly scrutinized.

Adult↗

[Epidemiology of carcinoma of the cervix (author's transl)].

In order to explain why modes of sexual life influence the incidence of cervical carcinoma, several factors have been claimed to be involved. There is no solid basis for the hypothesis that sperm may be mutagenic. By contrast, epidemiological studies showed that partners whose life is not sedentary bring back home to their wives an increased risk of cervical carcinoma. The infectious factor does not seem to be associated with syphilis but may well be represented by herpes genitalis virus (Herpes Simplex type 2 virus). Women with cervical carcinoma show a variety of immunes reactions to this virus, and these reactions are statistically less frequent in control groups. In the laboratory, mouse and hamster cells have been transformed into cancerous cells by means of herpes simplex virus type 2.

Adolescent↗

Cell-mediated immune response to simian oncornavirus antigens in pregnant women.

Tritiated thymidine incorporation into lymphocytes of 118 adult women was studied in the presence of mitomycin C-treated cells prepared from cell lines continuously producing Mason-Pfizer monkey virus (MPMV), baboon C-particle virus, or simian sarcoma virus (SSV) and in the presence of control cell lines documented for the absence of oncornaviruses. At the end of pregnancy, women who had 5-9 pregnancies showed a high frequency (53%) of specific positive responses to cells with MPMV antigens. The frequencies were 15% for pregnant women with smaller numbers of pregnancies and 3% for nonpregnant women with similar numbers of previous pregnancies as in the pregnancy group. None of these nonpregnant women had lymphocytes responding to stimulation by baboon C-virus antigens, but positive responses were obtained in 20 and 16% of the pregnant groups, respectively. No correlation was found between responses to MPMV or baboon C-virus antigens. Of 48 women (35 pregnant, 13 nonpregnant) who were tested for lymphocyte responses to SSV antigens, only 2 showed a positive response. The results indicated that two distinct antigens, related to MPMV and to baboon C-virus, may be expressed during pregnancy and may then induce a transient cell-mediated response.

Adult↗

Delay of tumor growth in hamsters treated with lynestrenol and effect of Staphylococcus aureus Cowan A.

The action of lynestrenol, a synthetic progesterone-like substance, was studied in Syrian golden hamsters inoculated with cells transformed by herpes simplex virus type I. Daily ip injections of 1 mg lynesterol/kg delayed tumor growth. Lynestrenol alone only slightly increased the survival of the animals. This effect was more marked when the animals were also given injections of Staphylococcus aureus Cowan A. Survivors showed an increased resistance to challenge with infected cells. Hamsters previously given injections of killed transformed cells and then challenged with living cells showed a facilitation of tumor growth. This facilitation was inhibited by lynestrenol alone or combined with S. aureus Cowan A.

Animals↗

Neutralization of Mason-Pfizer virus by sera from patients treated for renal disease.

Sera from 67 patients treated for renal diseases were assayed by as many as three different tests for activities against Mason-Pfizer virus (M-P V) antigens. Firstly, in patients studied before kidney transplantation, neutralizing activity against syncytium-forming units of M-P V was found in 50% of 24 cases of chronic glomerulonephritis but in only 10% of 20 cases with other diseases (P less than 0.01). These proportions were higher after treatments accompanying transplantation since, of the 19 patients without antibodies before graft, 53% showed a sero-conversion after this treatment. The incidence of M-P V antibodies did not correlate with the number of transfusions received by the patients. Neither did these antibodies correlate with the presence of antibodies to antigens associated with baboon endogenous virus or simian sarcoma virus; antibodies to the latter two viruses were found in 6 to 21% of the sera, with no specific distribution among the sera. Secondly, pseudotypes of vesicular stomatitis virus with M-P V antigens in their envelope were prepared; they were inactivated by 90% of the sera which neutralized M-P V syncytium forming units and by none of the negative sera. Thirdly, specific complement-dependent cytotoxic antibodies to HeLa cells producing M-P V were also found in 61% of the sera with neutralizing activity to M-P V and only in 12% of the sera which did not neutralize M-P V. Absorption experiments indicated that the serum activities against M-P V associated antigens were not due to anticellular antibodies directed against normal constituents of human cells. However, no evidence has been provided that the M-P V associated antigens reacting with the human sera were virus coded.

Adult↗

Antibody and cell-mediated immunity to herpes simplex virus in psychotic depression.

The incidence and antibody titers to herpes simplex virus (HSV) were found significantly higher in patients with psychotic depression as compared to normal controls. Furthermore, the cell-mediated immunity (CMI) to HSV in psychotic depression was similar to that observed after acute HSV infection or recurrence. The results suggest therefore an association between HSV infection and psychotic depression.

Acute Disease↗

The photoinactivation of an RNA animal virus, vesicular stomatitis virus, with the aid of newly synthesized psoralen derivatives.

The newly synthesized psoralen derivatives, 4' hydroxymethyl 4,5',8 trimethylpsoralen, 4' methoxymethyl 4,5',8 trimethylpsoralen, and 4' aminomethyl 4,5',8 trimethylpsoralen hydrochloride photoreact with the single-stranded RNA animal virus, Vesicular Stomatitis virus, VSV. This virus is inactivated 10(3) times more effectively by photoreaction with these compounds than when photoreacted with 4,5',8 trimethylpsoralen. Under these conditions the RNA virus remains more than 10(3) times less sensitive to inactivation by these new photoreagents than were two double-stranded DNA viruses, Herpes Simplex type 2 (HSV-2) and Vaccinia. Preliminary evidence for the generality of this result is discussed.

Coumarins↗

Specific non-immunoglobulin G antibodies and cell-mediated response to herpes simplex virus antigens in women with cervical carcinoma.

Non-immunoglobulin G-neutralizing antibodies to herpes simplex virus (HSV) type 2 were assayed in sera adsorbed with Staphylococcus aureus Cowan I. They were present in 8% of women with normal cervical smear and in 20, 41, and 74% of women with atypia, dysplasia, and cervical carcinoma, respectively. Lymphocytes of the patients were tested for in vitro transformation by killed HSV type 1 and HSV type 2 (HSV-2), as well as by mitomycin C-treated hamster cells transformed by HSV or other viruses or not transformed. Specific stimulation by the HSV-transformed cells occurred in 2, 22, and 40% of women with normal cervical smear, dysplasia, and carcinoma of the cervix, respectively. This frequency rose to 82% during treatment with irradiation and decreased to 0% after surgery. When HSV-2 virions were used as antigens to stimulate the lymphocytes, similar differences were found between the various groups, but they were less clear-cut, since 16% of the control women had lymphocytes responding to HSV. Non-immunoglobulin G antibodies to HSV-2 were not present in blood at the same time as cell response to HSV-2-transformed cells. There was also a negative correlation between neutralizing activities of the sera and the indices of lymphocyte stimulation, indicating a regulation between humoral and cell-mediated responses.

Antibodies, Viral↗

Repression of Escherichia coli carbamoylphosphate synthase: relationships with enzyme synthesis in the arginine and pyrimidine pathways.

Cumulative repression of Escherichia coli carbamoylphosphate synthase (CPSase; EC 2.7.2.9) by arginine and pyrimidine was analyzed in relation to control enzyme synthesis in the arginine and pyrimidine pathways. The expression of carA and carB, the adjacent genes that specify the two subunits of the enzyme, was estimated by means of an in vitro complementation assay. The synthesis of each gene product was found to be under repression control. Coordinate expression of the two genes was observed under most conditions investigated. They might thus form an operon. The preparation of strains blocked in the degradation of cytidine and harboring leaky mutations affecting several steps of pyrimidine nucleotide synthesis made it possible to distinguish between the effects of cytidine and uridine compounds in the repression of the pyrimidine pathway enzymes. The data obtained suggest that derivatives of both cytidine and uridine participate in the repression of CPSase. In addition, repression of CPSase by arginine did not appear to occur unless pyrimidines were present at a significant intracellular concentration. This observation, together with our previous report that argR mutations impair the cumulative repression of CPSase, suggests that this control is mediated through the concerted effects of regulatory elements specific for the arginine and pyrimidine pathways.

Arginine↗

Prognostic significance of hepatitis B antigenemia in kidney transplantation.

Serial hepatitis B antigen (HBAg) serum screenings were performed in 98 cadaver kidney transplant recipients: 51 were persistently found HBAg-negative while 47 became HBAg-positive, the majority of them acquiring HBAg postoperatively. In 28 patients, HB antigenemia persisted over 6 months postoperatively. 1- and 2-year graft survival rates were significantly greater in HBAg-positive than in HBAg-negative recipients. This finding suggests that HBAg tolerance is due to the ill-defined processes which determine kidney graft tolerance.

Adolescent↗