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Biomedical subjects

W Bossart

Publications and source records attributed to W Bossart.

At least 37 records · Page 2Linked to original sources
PubMed1992

Protection by a polyvalent vaccine against challenge infection and pyelonephritis.

The protective effect of immunization with a polyvalent vaccine (SolcoUrovac) was studied in the mouse and the rat. The i.m. immunization increased the resistance of mice to challenge infection with all homologous strains of bacteria. The LD50 values for E. coli, Proteus mirabilis and Streptococcus were 3.5-4.5 times and that of Klebsiella as much as 600 times that in nonimmunized mice. Protection against challenge with heterologous E. coli was also achieved and persisted for about 20 weeks. Immunization with the vaccine also provided marked protection against pyelonephritis in rats. Kidneys with abscesses were seen only one-third as often as in controls, and the size of the individual abscesses was substantially smaller in the vaccinated animals. Based on the quantity of bacteria in the kidneys it was postulated that the vaccination increased the clearance of bacteria.

Abscess↗
PubMed1992

[The effect of Lactobacillus acidophilus "Solco" on the immunological indices of totally decontaminated mice under complete gnotobiological isolation].

The possibility of stimulating the immunity of totally decontaminated mice, kept isolated under germ-free conditions, with the use of killed L. acidophilus Solco strains has been studied. As revealed in this study, the oral and intraperitoneal administration of strains O1 and O6 to mice leads to a significant increase in the content of immunoglobulin-synthesizing cells in the jejunal lamina propria of the animals. The oral administration of L. acidophilus Solco strain O6 and the intraperitoneal injection of L. acidophilus Solco strain O1 have been found to lead to a significant rise in the level of luminol-dependent chemiluminescence of mouse peritoneal macrophages. The total decontamination of mice induces the development of secondary immunodeficiency which influences the effectiveness of immunostimulating agents.

Animals↗
PubMed1989

Urinary antibody response after immunisation with a vaccine against urinary tract infection.

Immunisation of mice with SolcoUrovac vaccine induced an approximately 10-fold increase of the total amount of IgG and a 2-fold increase of IgA immunoglobulins in urine. IgG antibodies to SolcoUrovac antigens appeared in urine after the first injection, and booster injections caused a further increase of the titer. IgA antibodies appeared in the urine after the second injection, and the third injection doubled the titer. IgM immunoglobulins and specific IgM class antibodies to SolcoUrovac were not found in any urine tested. The exact origin of the immunoglobulins in the urine as well as the specificity of immune response is discussed.

Adjuvants, Immunologic↗
PubMed1984

Accumulation of poliovirus proteins in uninfected isolated HEp-2 cell nuclei in vitro.

Poliovirus (type 1, Mahoney) proteins preferentially inhibited in vitro RNA polymerase II activity in uninfected isolated HEp-2 cell nuclei, as demonstrated by electron microscopic autoradiography. Structural integrity of the nuclei and preincubation of nuclei and poliovirus proteins in vitro prior to addition of [3H]-UTP were prerequisites for differential inhibition. During in vitro incubation, [3H]-labeled poliovirus proteins were shown to accumulate in the uninfected isolated nuclei. Similar poliovirus proteins accumulated in the nuclei to higher relative amounts as compared to the outside or were excluded from the nuclei after in vitro incubation, as in intact poliovirus-infected cells. Since the in vitro transcription system of isolated nuclei exhibited two characteristics of poliovirus infection, i.e., preferential inhibition of RNA polymerase II activity and accumulation of poliovirus proteins in the nuclei, it may be useful to study host RNA synthesis inhibition.

Autoradiography↗
PubMed1983

Intracellular distribution of poliovirus proteins and the induction of virus-specific cytoplasmic structures.

In a susceptible cell, enteroviruses induce a vesiculated region (the "virus-induced vesicles") which is both the site of viral RNA synthesis as well as the site referred to morphologically, as the "cytopathic effect." Proteins of poliovirus (type I, Mahoney) were shown to migrate into the region of the virus-induced vesicles of infected HEp-2 cells. Five proteins (P2-5b, P3-4b, P3-6a, P3-7c, P3-9) were found to be associated with the vesicles themselves, either as intrinsic membrane protein (P3-9) or in a soluble form within the vesicles (P3-4b, P3-7c, and, partially, P3-6a) or bound to a DOC-resistant structure (P2-5b and a small amount of P3-6a). Partial inhibition of the cleavage of the viral polyprotein with ZnCl2 was used to alter the viral protein pattern within the cells. The data obtained indicate that P2-5b is the protein responsible for the formation of the virus-induced vesicles.

Carcinoma, Hepatocellular↗
PubMed1982

Poliovirus-induced inhibition of host RNA synthesis studied in isolated HEp-2 cell nuclei.

Nuclei isolated from uninfected HEp-2 cells synthesized RNA for 60 to 90 min. The individual RNA polymerase activities were determined by alpha-amanitin differential inhibition and the RNA products characterized by electron microscope (EM) autoradiography and sucrose gradient centrifugation. In nuclei prepared from poliovirus-infected cells, the capacity to synthesize RNA in vitro decreased with time after infection. RNA polymerase II activity (hnRNA synthesis) was preferentially inhibited more than was the polymerase I activity (rRNA synthesis). Poliovirus-infected cytoplasm (S-30) inhibited in vitro RNA synthesis in uninfected nuclei by selectively affecting the polymerase II activity. Selective inhibition of hnRNA synthesis by the crude extracts could be monitored by EM autoradiography directly. Determinations of individual RNA polymerase activities by differential alpha-amanitin inhibition were done only after treatment of the infected cytoplasm with micrococcal nuclease to abolish virus RNA replication. Selective inhibition of hnRNA synthesis depended on preincubation of the nuclei together with the infected cytoplasm, indicating that inhibitory substances from the infected cytoplasm entered the nuclei. Isolated nuclei therefore provide a useful system for studying the nature of the inhibitor(s) and of host RNA synthesis inhibition by picornaviruses.

Cell Line↗
PubMed1982

Accumulation of poliovirus proteins in the host cell nucleus.

Poliovirus (type 1, Mahoney) proteins were transported into the nuclei of HEp-2 cells, as demonstrated by means of electron microscopic autoradiography. Quantitative determinations of the proteins by electrophoresis showed that the relative amounts of precursor proteins (1a, 3b, 1b), of some of the intermediate polypeptides (3a, 3c, 5b, 2), and of one end product (VP1) were higher in the nucleus than in the cytoplasm. Other proteins (VPO, VP2, X, 4, 6a) were found in the same relative amounts in the nucleus as in the cytoplasm, whereas two proteins (VP3 and 6b) were excluded from the nucleus. The findings are discussed in view of the recently demonstrated inhibitory activity exerted by cytoplasmic extracts of poliovirus-infected cells on transcription in isolated nuclei of uninfected cells.

Cell Compartmentation↗
PubMed1978

Effect of UV irradiation on the expression of vaccinia virus gene products synthesized in a cell-free system coupling transcription and translation.

The effect of UV irradiation on the expression of the vaccinia virus genome was investigated in a cell-free system coupling transcription with translation. Exposure of vaccinia virus to an increasing dose of irradiation resulted in differential reduction in the syntheses of virus-specified polypeptides in the coupled system, with sensitivity being proportional to the size of the gene pro duct. This suggests that each translationally functional mRNA species produced in vitro by vaccinia virus cores is synthesized from an individual promoter site.

Cell-Free System↗
PubMed1978

Cell-free translation of purified virion-associated high-molecular-weight RNA synthesized in vitro by vaccinia virus.

Virion-associated high-molecular-weight (HMW) RNA synthesized in vitro by purified vaccinia virus particles has been translated in a wheat germ cell-free protein synthesizing system. Purified HMW RNA directs the synthesis of translation products which are identical to the translation products made in response to in vitro-synthesized, virion-released 8 to 12S mRNA. The translation of HMW RNA proceeds exclusively through a 5'-terminal cap-mediated initiation step. Furthermore, only one coding sequence is translated per HMW RNA molecule, and that sequence is probably located near the 5' end of the molecule. These conclusions are based on the following results. (i) Sodium dodecyl sulfate--polyacrylamide gel electrophoresis patterns of translation products synthesized in response to HMW RNA and in response to 8 to 12S mRNA were qualitatively identical. (ii) On an equal weight basis, HMW RNA was 25 to 30% as active as 8 to 12S mRNA in stimulating in vitro protein synthesis. (iii) Unmethylated HMW RNA was translated at 10% the efficiency of the methylated form of this RNA. (iv) m7pG inhibited the translation of fully methylated HMW RNA by 90%. (v) After the initiation step of translation was blocked by aurintricarboxylic acid, the rate with which amino acids were incorporated into individual polypeptides decreased in a similar manner for the translation of both HMW RNA and 8 to 12S mRNA. Virion-released 8 to 12S mRNA derived from virion-associated HMW RNA during a chase in the presence of ATP, GTP, and S-adenosylmethionine was also translated. At low RNA concentrations, the derived RNA appeared to stimulate amino acid incorporation more efficiently than the HMW RNA precursor. However, at higher concentrations of this RNA, protein synthesis was severely inhibited.

Aurintricarboxylic Acid↗
PubMedDate not supplied

Retrospective analysis of varicella zoster virus (VZV) copy DNA numbers in plasma of immunocompetent patients with herpes zoster, of immunocompromised patients with disseminated VZV disease, and of asymptomatic solid organ transplant recipients.

BACKGROUND: Varicella zoster virus (VZV) causes significant morbidity and mortality in immunocompromised patients. Subclinical reactivation has been described in solid organ recipients and has been associated with graft versus host disease in bone marrow transplantation. Newer studies assessing the prevalence and impact of subclinical VZV reactivation in solid organ transplant (SOT) recipients are lacking. METHODS AND RESULTS: In a first step we developed a highly sensitive quantitative polymerase chain reaction (qPCR) assay for VZV DNA with a detection limit of < or = 20 copies/mL. Using this assay, we retrospectively analyzed plasma samples of different patient groups for VZV DNA. VZV DNA was found in 10/10 plasma samples of immunocompetent patients with herpes zoster (VZV copy numbers/mL: mean+/-SEM 1710+/-1018), in 1/1 sample of a human immunodeficiency virus-infected patient with primary VZV disease (15,192 copies/mL) and in 4/4 plasma samples of immunocompromised patients with visceral VZV disease (mean of first value 214,214+/-178,572). All 108 plasma samples of asymptomatic SOT recipients off any antiviral therapy, randomly sampled over 1 year, were negative for VZV DNA. CONCLUSION: Our qPCR assay proved to be highly sensitive (100%) in symptomatic VZV disease. We did not detect subclinical reactivation in asymptomatic SOT recipients during the first post-transplant year. Thus, subclinical VZV reactivation is either a rare event or does not exist. These data need to be confirmed in larger prospective trials.

Adult↗
PubMedDate not supplied

[The effect of SolcoTrichovac on the vaginal microflora of patients with a papillomavirus infection associated with a cervical intraepithelial neoplasm].

The microbiological study of vaginal secretions of 39 female patients of reproductive age (20-30 years) with papilloma virus infection associated with cervical intraepithelial neoplasia (CIN) was carried out. Of these patients, 28 with papilloma virus infection associated with CINI-II made up group I and II having this infection associated with CINII made up group 2. Dysbiotic disturbances in vaginal bacterial flora, found in these patients, were manifested by a decrease in the isolation rate and number of the lacto- and bifidobacteria simultaneously with the excessive growth of opportunistic bacteria. The results of the oral administration of Solco-Trichovac are indicative of the effectiveness of this preparation, which was confirmed by the data of clinical and bacteriological studies. Together with an increase in the isolation rate of lacto- and bifidobacteria, the level of the contamination of the cervicovaginal niche with opportunistic and pathogenic bacterial strains decreased. The results thus obtained make it possible to recommend Solco-Trichovac for the complex treatment of with papilloma virus infection associated with CIN.

Adjuvants, Immunologic↗