Suppressor T-cell activity in chronic hepatitis B-virus infection: relationship with the presence of HBV-DNA in serum

Suppressor T-cell activity and allogeneic T-cell response to concanavalin A (ConA) were investigated in 46 patients chronically infected with hepatitis B virus (HBV). Thirty-eight patients had chronic active hepatitis, seven of whom were superinfected with Delta virus, and eight were healthy chronic HBV carriers. T-cell suppressor activity was in the normal range in healthy carriers and in patients negative for serum HBV-DNA, independent of the e antigen status. In contrast, the group of patients positive for HBV-DNA exhibited a significant reduction in suppressor activity. Longitudinal studies in patients who cleared serum HBV-DNA demonstrated that suppressor T-cell activity became normal thereafter. These results suggest a relationship between suppressor T-cell function and the stage of viral replication in individuals with chronic HBV infection.

Protein-primed replication of bacteriophage phi 29 DNA

The replication of phi 29 DNA-protein p3 represents a simple model system to study the protein-priming mechanism of initiation of replication. The phi 29 DNA polymerase involved both in the initiation and elongation steps of phi 29 DNA-protein p3 replication, is a very processive enzyme and it is able to produce strand-displacement in the absence of other proteins. To correlate functional and structural domains in the phi 29 DNA polymerase point mutants in the most carboxyl region of amino-acid homology with other DNA polymerases have been constructed. Most of the mutations had a decreased initiation and elongation activity, but normal 3'----5' exonuclease activity, suggesting that this region contributes to the active domain for initiation and elongation. Point and deletion mutants in the terminal protein have allowed the mapping of one DNA-binding region and two DNA-polymerase-binding regions. The viral protein p6, which stimulates the initiation of replication, binds to a set of specific signals present at both phi 29 DNA ends. A good correlation of binding and stimulation of replication has been obtained by using fragments containing phi 29 DNA-terminal sequences and deletion mutants of protein p6. The viral protein p5 has been shown to bind to single-stranded DNA, to protect the latter against nuclease digetion, and to stimulate phi 29 DNA-protein p3 replication in vitro.

Interaction of the bacteriophage phi 29 protein p6 with double-stranded DNA

The Bacillus subtilis bacteriophage phi 29 protein p6 binds to double-stranded DNA, but not to single-stranded DNA, as determined by a gel retardation assay. The nature of the interaction was further studied by DNase I "footprinting" experiments. Protein p6 binds to fragments containing the right or left terminal sequences of phi 29 DNA, producing a characteristic pattern of hypersensitive bands spaced about 24 nucleotides apart along most of the fragment, flanking protected regions. Binding of protein p6 to an internal phi 29 DNA fragment was also observed, but the footprint pattern was more salt sensitive than that obtained with the terminal phi 29 DNA fragments. By electron microscopy, protein p6 was shown to cover the DNA, totally or partially, from one end. In addition, binding of protein p6 to relaxed circular DNA induced positive supercoiling, indicating that a topological change in the DNA occurred.

Interleukins in chronic active hepatitis B. Relationship with viral markers

Interleukin-2, a product of helper T cells, is essentially involved in the regulation of cell-mediated immunity. Two monocyte-derived factors, interleukin-1 and prostaglandin E2, influence interleukin-2 synthesis with opposite actions. To analyse immunoregulatory function in HBsAg-positive chronic active hepatitis, T cell subsets in peripheral blood and the levels of interleukin-2, interleukin-1 and prostaglandin E2 in supernatants from lectin- or lipopolysaccharide-activated peripheral mononuclear cell cultures were determined in 16 healthy controls and 33 patients with chronic active hepatitis B. Interleukin-2 activity was comparable to the controls in patients without delta infection who had seroconverted to anti-HBe (group 1), but it was significantly reduced in both HBeAg-positive subjects (group 2) (P less than 0.05 vs. controls and group 1) and those cases with positive delta markers (group 3) (P less than 0.01 and less than 0.05 vs. controls and group 1, respectively). In group 3, interleukin-2 was similarly diminished in both anti-HTLV-III-positive and -negative cases as well as in HBeAg- and anti-HBe-positive subjects. Notwithstanding the changes in interleukin-2 activity, no significant differences in the number of T4 cells, or in the levels of either interleukin-1 or prostaglandin E2, were found among the various groups of subjects studied. However, in those groups with reduced interleukin-2 activity an increased number of T8 cells was observed. It is suggested that the low levels of interleukin-2 found in the replicative phase of chronic active hepatitis B and in delta superinfection reflect a disturbed immunoregulation that may contribute to persistent viral replication in these two conditions.

[Kinetin and the germinating capacity of Lupinus multilupa seeds]

The effect of kinetin (10(-6) M and 10(-4) M) on the germinating capacity and incorporation of 8-C14 adenine into DNA, RNA and RNA Poly A+ of embryos and cotyledons from Lupinus multilupa L. seeds have been studied. Kinetin enhanced the germinative capacity of the seeds and the incorporation of 8-C14 adenine into DNA, RNA and Poly A+ of embryos and cotyledons. However, there seems to be no close relationship between the DNA and RNA biosynthesis of embryos and cotyledons and the ability of the seeds to germinate and their embryos to continue growing.

Immune complexes in epidemic (type A) hepatitis. Detection by three methods using laser nephelometry

Thirty-eight children with acute epidemic hepatitis (Type A) and 22 children in "contact" with the disease, 5 of whom subsequently developed hepatitis, were studied. Three technics based on laser ray nephelometry were employed to investigate the presence of circulating immune complexes. Our results indicated that circulating immune complexes are present in the serum during the course of epidemic hepatitis. These were demonstrated in 79% of the patients. The capacity to fix complement diminishes as the disease evolves toward the convalescent phase. We also detected a similar percentage of immune complexes (80%) in the patients during the incubation period. In the subjects in "contact" with the disease who subsequently did not develop hepatitis, the immune complexes were shown to have a greater capacity to fix complement, and the percentage of immune complexes present was higher (94%). The specificity of the immune complexes was verified by correlating the antivirus A antibody activity with the percentage of C4 in the precipitates obtained by polyethylene glycol (3.5%).

Immunological aspects of sarcoidosis associated with true thymic hyperplasia

A 34-year-old woman had a three-month history of a double mitral lesion. Chest radiographs disclosed a mediastinal mass. Thoracotomy was performed and multiple white nodules and an enlarged thymus were seen. Sarcoidosis and true thymic hyperplasia were diagnosed in the excised white nodules and thymus. A decrease of cell-mediated immunity was also discussed. When commissurotomy of the mitral valve was performed 4 months later, sarcoidosis and true hyperplasia had disappeared and alterations of cell-mediated immunity became normal after a course of steroid therapy. The alterations of cell-mediated immunity, so frequent in sarcoidosis, could be related to true thymic hyperplasia.

[Hepatosplenic sarcoidosis. Apropos of a case]

We present a case of hepatosplenic sarcoidosis without associated pulmonary affection. We have also revised the literature in this respect with special emphasis on the etiopathogenic aspects. The evolution and treatment followed during the period two liver biopsies were performed. The good response to treatment with steroids, clinically and histopathologically, are commented on.

A controlled study of a dopa decarboxylase inhibitor (benserazide) in the treatment of schizophrenic patients

In a double-blind controlled study lasting 6 weeks, 32 schizophrenic patients were randomly assigned to one of two treatments: chlorpromazine or benserazide, a dopa decarboxylase inhibitor. Results on each measure were subject to multifactorial analysis of covariance. Benserazide did not appear to be as effective an antipsychotic medicaiton as chlorpromazine. In fact, chlorpromazine was significantly better on measures of tension, excitement, hallucinatory behavior, thinking disturbance, social interest, and drop-out rate. At the relatively low dosages used in this study, it would seem that benserazide had little effect on the cerebral dopa decarboxylase, and it would be worthwhile trying higher dosages.

Amitriptyline-perphenazine interaction in ambulatory schizophrenic patients. A controled study of drug interaction

In a double-blind placebo, controlled clinical study, lasting 12 weeks, 48 male and 48 female ambulatory schizophrenic patients were randomly assigned to one of four treatments: placebo; amitriptyline hydrochloride, 125 mg/day; perphenazine, 20 mg/day; or amitriptyline-perphenazine, 20 mg/day. Treatment groups contained an equal number of male and female patients. Perphenazine alone or in combination was substantially more effective in reducing psychopathological disorder than was the placebo, but there was no evidence to indicate the superiority of the amitriptyline-perphenazine combination over perphenazine alone. Amitriptyline alone was not substantially better than placebo and could not be considered an efficacious medication for the maintenance treatment of these patients. Less response to treatment was made by patients with longer-term records of prior hospitalization.