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Biomedical subjects

G Hess

Publications and source records attributed to G Hess.

At least 127 records · Page 7Linked to original sources
PubMed1990

[Diagnosis of hepatitis C virus (HCV) infection: diagnostic value of the anti-HCV test].

Different groups of patients were analysed for antibody to hepatitis-C-virus (anti-HCV). A high prevalence was found in individuals with parenteral exposure (chronic Non-A, Non-B hepatitis, 77.5%, drug addicts 84.5%), while blood donors had a prevalence of 0.51%, this was significantly higher in patients with chronic type B hepatitis (30%), in homosexuals (22.5%) and in patients with different types of autoimmune hepatitis (57.2%). This indicates that differential diagnosis of chronic hepatitis and indications for alpha interferon therapy is not possible by simply anti-HCV testing. Further studies are required to establish the diagnostic value of the anti-HCV test.

Antibodies, Viral↗
PubMed1990

[A quantum analysis of the long-term posttetanic changes in the minimal postsynaptic potentials in surviving hippocampal slices].

Excitatory postsynaptic potentials (EPSPs) were recorded in guinea pig hippocampal slices (area CA1) from 13 neurons after single or double-pulse stimulation of stratum radiatum (the Schaffer collaterals) and stratum oriens. Amplitudes of 23 EPSPs (9 neurons, 12 pathways) grew 5 to 55 min after 10 tetanic stimulations of the Schaffer collaterals. This increase has been considered as a long-term potentiation (LTP). A statistical analysis was carried out by four methods of the quantal hypothesis based on the binomial distribution. It revealed an increase in the mean quantal content (m) during LTP. An increase in the quantal size was also observed in the majority of the cases but it showed only a weak correlation with the LTP magnitude and for some methods it was statistically significant only for the periods later than 15 min after tetanic stimulation. A well expressed increase in m demonstrated by various methods corresponds to data of the previous in vivo studies and favours the presynaptic location of mechanisms of the LTP maintenance.

Animals↗
PubMed1990

[A quantal analysis of the long-term potentiation of the total postsynaptic neuronal potentials in surviving hippocampal slices].

Excitatory postsynaptic potentials (EPSPs) from 14 neurons have been recorded in hippocampal slices (area CA1) of guinea pigs after stimulation of stratum radiatum (Schaffer collaterals) and stratum oriens. An increase of EPSP amplitudes observed in 7 neurons (9 pathways) recorded 15-45 min after titanic stimulation of Schaffer collaterals is considered as a long-term potentiation (LTP). A statistical analysis in the frame of two methods of the quantal hypothesis (histogram and variance methods) has shown an increase in the mean quantal content (m) during LTP. An increase in the quantal size found only by the histogram method is considered to be less reliable because comparatively strong dependence of the histogram method on the noise level. An increase in m revealed by two methods corresponds to the previous in vivo studies and favours a presynaptic location of mechanisms responsible for the growth of the synaptic efficacy during LTP.

Animals↗
PubMed1989

[Monoclonal gammopathy in HIV infection].

A lambda-light chain-IgA plasmocytoma, accompanied by a changing clinical picture of fever, nocturnal perspirations and weight loss, developed in a 46-year-old homosexual male with AIDS, stage IV (classification according to the Centers for Disease Control). He had been suffering from recurrent Salmonella septicaemia. Serum protein electrophoresis demonstrated marked elevation of the beta- and gamma-fractions (44% and 24%, respectively). There were 15% plasma cells in the differential blood count and in the bone marrow smear. Immunoelectrophoresis demonstrated free lambda-light chains. The IgA concentration in cerebrospinal fluid was raised to 202 mg/l, and there was an IgA paraproteinaemia. The patient died during a recurrence of the Salmonella septicaemia from septic cardiovascular failure.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Molecular dynamics of the alpha-helical epitope of a novel synthetic lipopeptide foot-and-mouth disease virus vaccine.

A novel synthetic foot-and-mouth disease virus (FMDV) peptide vaccine consisting of a synthetic B-cell and macrophage activator covalently linked to an amphiphilic alpha-helical T-cell epitope was developed. The low molecular weight vaccine of 3400 daltons is composed of virus VP1 antigenic determinant and the immunologically active lipotripeptide tripalmitoyl-S-glyceryl-cysteinyl-seryl-serine (P3CSS) as built-in adjuvant. The vaccine, tripalmitoyl-S-glyceryl-cysteinyl-seryl-seryl-FMDV-VP1 (VP1 = serotype O1K 135-154) induces protection against homologous challenge and serotype-specific virus neutralizing antibodies in guinea pigs after single administration without further adjuvants or carriers. A P3CSS conjugate with the FMDV-VP1 segment 135-154 of strain O Wuppertal produced only poor cross-protection against challenge with O1K virus. The antigenic determinant VP1(135-154) is an amphiphilic alpha-helix, as shown by CD. Molecular dynamics simulations (MDS) carried out using the highly homologous alpha-helical alcohol dehydrogenase (ADH) segment H3 as starting conformation for VP1(138-149) suggest that the FMDV segment 138-149 may adopt alpha-helical conformation during binding to its T-cell receptor, and that the development of the system during MDS may be considered as the dissociation step of the complex.

Amino Acid Sequence↗
PubMed1989

Treatment of chronic type B hepatitis with recombinant alpha-interferon induces autoantibodies not specific for autoimmune chronic hepatitis.

Recombinant human alpha-interferon is now under intensive investigation as therapy for chronic Type B hepatitis. Recent reports have suggested that prolonged alpha-interferon therapy may induce autoimmune reactions. We have evaluated the problem of autoimmunity related to alpha-interferon therapy by testing for 15 different antibodies in the sera of 31 patients treated with alpha-interferon. No patient had autoantibodies before treatment; 27 (87%) of 31 patients developed at least one autoantibody. Eleven patients had antinuclear antibodies and 21 had smooth muscle antibodies, both of which usually developed during alpha-interferon therapy. In contrast, antibodies to endocrine organs such as thyroid microsomal, thyroglobulin and parietal cell antibodies arose in 12 patients, but usually several months after alpha-interferon treatment. The appearance of these autoantibodies did not correlate with disease activity or response to alpha-interferon. No patient developed autoantibodies specifically associated with autoimmune liver diseases such as liver kidney microsomal antibodies, autoantibodies to soluble liver antigen and the primary biliary cirrhosis specific subtypes of antimitochondrial antibodies. These results suggest that prolonged alpha-interferon therapy can induce autoantibody production and, in susceptible patients, may lead to autoimmune disorders.

Antibody Specificity↗
PubMed1989

Active immunization of homosexual men using a recombinant hepatitis B vaccine.

Twenty homosexual men [13 anti-human immunodeficiency virus (HIV)-positive, seven anti-HIV negative] without HBsAg, anti-HBs, and anti-HBc were vaccinated with three 20 micrograms doses of a recombinant hepatitis B vaccine. All anti-HIV-positive homosexuals were nonresponders independent of the initial number of CD4-positive cells. Among seven anti-HIV-negative individuals, five responded. After three doses of the vaccine, CD4-positive cells fell in anti-HIV positive individuals by 22.4%. A similar fall in CD4-positive cells of an average 24.9% was noted in 17 matching, but nonvaccinated, anti-HIV-positive homosexuals. The study indicates that the efficacy of vaccination in anti-HIV-positive individuals is questionable. There is, however, no evidence that vaccination against hepatitis B might be harmful to anti-HIV-positive subjects.

Adolescent↗
PubMed1989

Immune blot analysis of viral surface proteins in serum and liver of patients with chronic hepatitis B virus infection.

The small and the middle surface proteins of hepatitis virus form either the virion or the 22 nm particle both of which are secreted. The large surface protein by itself remains cell bound in artificially transfected cell culture unless it is accompanied by an excess of the smaller protens. Its behavior in vivo is not yet well studied. Using specific monoclonal antibodies for immunoblotting, we found an abundance of small surface protein in the serum of chronic virus carriers and moderate amounts in the liver irrespective of viremia. The large surface protein was present in the serum and the liver of viremic carriers. In nonviremic carriers, the large protein was absent from serum, but in the liver a shorter form of the large protein was readily detectable. These findings suggest a complex regulatory mechanism of the viral surface protein depending on the expression of other viral gene products.

Adult↗
PubMed1989

Antibodies to hepatitis B virus x-protein in sera of patients with acute and chronic active hepatitis.

Sera of patients with acute (AH) and chronic active hepatitis (CAH) were tested for anti-hepatitis B virus (HBV) x-protein (HBx) by immunoblotting, using recombinant MS2- and beta gal-HBx fusion proteins as substrate. Antibodies against HBx were detected in 5 out of 17 patients with AH at an early stage of infection, and in 13 out of 35 patients with CAH. Positive sera from AH patients showed a relatively weak anti-HBx reactivity when compared to sera from CAH patients. In follow up studies we tested serial serum samples from patients positive for anti-HBx. Patients with AH were observed for 3 to 6 weeks and CAH patients for up to 51 months. In general anti-HBx reactivities appeared to be stable although significant differences in apparent antibody levels were noted when sera from individual patients were compared. Our data further support an early expression of HBx-antigen in HBV-infected individuals. There was no correlation between HBe-antigen and anti-HBx in CAH.

Blotting, Western↗
PubMed1989

Modification of the immune response against hepatitis B virus by the human immunodeficiency virus.

Hepatitis B virus and the human immunodeficiency virus are similarly transmitted. Individuals with preexisting HIV infection have a higher chance to become HBsAg carriers than do anti-HIV negative persons. Cytotoxic T cells with specificity for HBcAg, that are under the control of HBcAg-specific helper T cells, are responsible for liver injury. There is good evidence that HIV infection lowers inflammatory activity, is associated with milder liver histology, high levels of viral replication and low seroconversion rates. In addition interferon alpha therapy is less effective in anti-HIV positive subjects. The immune response against HBsAg is helper T-cell dependent and vaccination against hepatitis B is of low effectiveness. In addition, vaccination against hepatitis B may activate the HIV disease and is, therefore, presently not to be recommended.

Carrier State↗
PubMed1989

Treatment of protracted acute type B hepatitis with recombinant alpha-A-interferon. A pilot study.

Six individuals with protracted acute type B hepatitis were treated with recombinant alpha-A-interferon for 12 weeks. Two females eliminated the HBV completely, while 4 males did not respond. Response was preceded by a flare-up of the liver disease. It appears that responses to interferon are not higher in protracted acute type B hepatitis than in progressed chronic active hepatitis B. This assumption has to be proven in larger studies on a statistical basis.

Acute Disease↗
PubMed1989

Novel low-molecular-weight synthetic vaccine against foot-and-mouth disease containing a potent B-cell and macrophage activator.

Most synthetic peptide vaccines described to date are effective only in combination with proteins and Freund's adjuvant. The work describes a novel completely synthetic virus peptide vaccine, which consists of a synthetic activator of B cells and macrophages, covalently linked to an amphiphilic alpha-helical T-cell epitope. The low-molecular-weight vaccine of 3.4 kDa developed against foot-and-mouth disease virus (FMDV) is composed of a synthetic VP1 (135-154) with a sequence homologous to an FMDV protein and the adjuvant tripalmitoyl-S-glyceryl-cysteinylserylserine (P3CSS). P3CSS is the synthetic analogue of the N-terminal part of the lipoprotein from Gram-negative bacteria. The antigenic determinant VP1 (135-154) is an alpha-helix as shown by circular dichroism. The resulting novel type of vaccine tripalmitoyl-S-glyceryl-cysteinylserylseryl-FMDV-VP1 (135-154) induces a long-lasting high protection against foot-and-mouth disease and serotype-specific virus-neutralizing antibodies in guinea-pigs after a single administration without any additional adjuvant or carrier. In contrast to other simple fatty acid conjugates this new type of vaccine contains a built-in adjuvant with high affinity to both B and T lymphocytes.

Adjuvants, Immunologic↗
PubMed1989

Comparative analysis of monoclonal antibodies against pestiviruses: report of an international workshop.

Thirty-three pestivirus strains were grown in cell culture and characterized by immunostaining with 19 monoclonal antibodies (MAbs) raised against hog cholera virus (HCV), with 42 MAbs against bovine viral diarrhoea virus (BVDV) and with 13 MAbs against border disease virus (BDV). Seven MAbs reacted with all pestivirus strains tested, eight MAbs detected only the seven HCV strains, three detected only the 16 BVDV strains. No MAb was found that was specific for BDV. BVDV and BDV strains were broadly cross-reactive with the MAbs, indicating a close relationship between these two species, whereas HCV strains were characterized as distinct from BVDV and BDV.

Animals↗
PubMed1989

[Epidemiologic, infectiologic and immunologic results from gynecologic HIV consultation at the Mainz University Gynecologic Clinic].

For more than two years, all HIV-positive women were seen in the Department of Obstetrics and Gynaecology in cooperation with the Department of Internal Medicine of the University of Mainz, for medical care and therapy, if necessary. Of 40 HIV-infected female patients who were treated, 25 women were followed up every three to six months. Most of the latter live in rural areas or outside the cities in the State Rhineland Palatinate, FRG. 52% of them are or were former intravenous drug abusers, and 44% had been infected by sexual transmission. Only one-third use condoms during intercourse, another third reject this kind of protection. The rest are without cohabitation for various reasons. 23 pregnancies are known in this group and in 20% of the cases HIV infection were discovered during prenatal care. Gynaecological and obstetrical findings are reported. 80% of the patients have had a recurrent candida infection of the vagina, which was detected by culture. Immunologically, 75% of the patients belong to stage III (according to the CDC classification). Out of this group, more than 50% show less than 400 CD4 (+) cells/microliters. A positive result for HIV-Ag, anti-p41 and negative anti-p24 was seen in five cases. One of the four patients with AIDS died of a rapidly growing cancer of the cervix.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Interferon production in patients infected with HIV-1.

The production of interferon (IFN) from cultured peripheral blood mononuclear cells (PBMC) after virus or mitogen stimulation was evaluated in 141 patients positive for antibodies to human immunodeficiency virus type 1 (HIV-1). IFN-alpha production by PBMC of patients at Centers for Disease Control (CDC) stage II (Walter Reed [WR] 1) was comparable to that produced by PBMC of healthy controls. However, cells of patients at early CDC stage III (WR 2) produced significantly lower titers of IFN-alpha (P less than .001), and IFN-alpha was almost absent at CDC stage IV (WR 6) (P less than .001). IFN-gamma production was altered in patients at late CDC stage III (WR 4-5) and CDC IV (WR 6). A strong correlation between the disappearance of antibodies to core proteins and low IFN-alpha level was observed. IFN-alpha levels were significantly diminished in patients positive for HIV antigen. Reduced IFN-alpha production paralleled the HIV-1-related depletion of CD4+ lymphocytes and might serve as an additional parameter in defining the stage of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Treatment of patients with chronic type B hepatitis and concurrent human immunodeficiency virus infection with a combination of interferon alpha and azidothymidine: a pilot study.

Six patients with chronic type B hepatitis and concurrent infection with the immunodeficiency virus were treated with 600 mg azidothymidine (AZT)/day and 3 X 10(6) units of interferon-alpha (IFN-alpha) every other day for a total of 4 months. None of the patients treated lost the hepatitis B virus (HBV). HBV-DNA concentrations were not significantly influenced by this treatment. Human immunodeficiency virus (HIV) infection was also not affected except for a transient rise in CD 4-positive cells in 2 individuals, who had initially low CD 4-positive cells. Treatment did not influence the presence of HIV-Ag in the serum. In conclusion, a combination therapy of IFN and AZT does not seem to be beneficial at the doses given and the time involved.

Adult↗