Joseph Ongrádi
University of South Florida
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Featured researches published by Joseph Ongrádi.
Journal of NeuroVirology | 1999
Joseph Ongrádi; Cecilia Rajda; Csaba László MarÓdi; Anna Csiszar; László Vécsei
In the possible role for human herpesviruses (HHV) in the pathogenesis of multiple sclerosis (MS) neither clear distinction between the two variants of HHV-6, nor the involvement of HHV-7 have been described. Therefore, we quantitated HHV-6 variant specific and HHV-7 reacting antibodies in the CSF of 13 patients with MS or other neurological disorders by ELISA. Predominance in the positivity of IgG (67%) and IgM (44%) to HHV-6B over that of IgG (44%) with no detectable IgM to HHV-6A, and no antibodies to HHV-7 were found in the CSF of MS patients. None of these antibodies were found in the CSF of controls. This suggests that, intrathecal chronic active or primary HHV-6B infection might contribute to MS progression, while the local effects of HHV-6A and HHV-7 seem to be less important.
International Journal of Immunopharmacology | 1992
John W. Hadden; Joseph Ongrádi; Steven Specter; Robert P. Nelson; Marina Sosa; Craig R. Monell; Mette Strand; Alfredo Giner-Sorolla; Elba M. Hadden
MIMP is a new thymomimetic purine under development for immunorestorative therapy. Lymphocytes were obtained from eight patients with acquired immunodeficiency disease (AIDS), eight with symptomatic pre-AIDS (ARC), and 22 normal controls and were stimulated in vitro with phytohemagglutinin (PHA). AIDS patients (mean CD4 counts of 40) showed PHA responses less than 10% of control while ARC patients (mean CD4 counts of 544) showed responses approximately 50% of the control responses. MIMP (0.1, 1, 10 and 100 micrograms/ml) progressively augmented the PHA responses in all these groups. The augmentation of the responses of the leukocytes of AIDS patients while statistically significant was minimal. The augmentation of the responses of ARC patients was significant and their maximal responses approached control levels. The effect of 1 micrograms/ml MIMP was comparable with that observed with indomethacin (10(-6) M) and interleukin-2 (IL2 - 4 units/ml) and was additive with each of these stimulants. In a parallel manner, MIMP restored the suppression of control lymphocytes induced by the immunosuppressive 17 amino acid fragment of the P41 peptide of HIV. In vivo experiments showed that MIMP significantly delayed death in a murine FLV AIDS model at a dose of 1 mg/kg by the oral or parenteral route. MIMP is under preclinical development for early HIV disease to forestall progression to AIDS by attenuating virus-induced immunosuppression.
Pathology & Oncology Research | 1998
Joseph Ongrádi; Steven Specter; Attila Horváth; Herman Friedman
Both marijuana and retroviruses impair natural killer (NK) cell functions, but no data on their simulataneous effects are available. Similarities to human AIDS induced by Friend leukemia complex (FLO and its helper Rowson-Parr virus (RPV) provides a mouse model to study drug-virus action. Leukemia susceptible BALB/c and resistant C57BL/6 mice were infected, then at time intervals their nylon wool-separated splenocytes were exposed to tetrahydrocannabinol (THC) for 3h. Natural killer cell activity against Yac-1 cells was assayed by 51Cr-release for 4 and 18h. Recovery of splenocytes was found to be suppressed by FLC, but in BALB/c only by RPV. After a transient enhancement in C57BL/6 by FLC, NK cell activity of both mice became suppressed early (2 to 4 days), normalized subsequently and enhanced late (11 to 14 days) postinfection. A moderate increase in BALB/c, no change in C57BL/6 were induced by low (1-2.5 g/ml) THC doses. NK cell activity of BALB/c became suppressed exponentially by higher (5-10 g/ ml) THC doses in 18h as compared to 4h assays, while its proportional and moderate impairment was seen in C57BL/6. The magnitude of NK cell activity of infected mice was determined by THC: enhancement or impairment followed those of untreated, infected counterparts on the level of THC-treated cells. Low doses hardly, high doses additively influenced NK cells of infected BALB/c. THC slightly affected very early and late enhancement in NK cell activity of FLC infected C57BL/6, but augmented RPV induced suppression late in 18h assays. Genetic factors similar to endotoxin resistance, altered cytokine profile might determine these effects. Similar phenomena in humans might result in earlier manifestation of AIDS.
Pathology & Oncology Research | 2000
Joseph Ongrádi; Helen M. Laird; Joseph F. Szilágyi; Attila Horváth; Mauro Bendinelli
C8166 cells express T lymphocyte markers, a monocyte-specific esterase,tax polypeptide of HTLV-I. In spite of this transactivator, their HIV-1 yield is low. Their culture conditions were modified, and infected cells were immobilized on a poly-L lysine sheet under semisolid overlays to study their phenotypic alterations and HIV-1 production by microscopy and electron microscopy. Another lymphoid cultures (MT-4, CEM, CEM-ss, AdCEM) similarly treated were infected with either HIV-l/RF or IIIB. Specificity of HIV-1 was compared to the effects of vesicular stomatitis virus (VSV). Unlike other cultures, HIV-l/RF infected C8166 cells in Eagle’s MEM exhibited surface projections resembling hairy leukemia cells, which was followed by balloon degeneration and apoptosis. Immobilized HIV-1 infected cultures formed flat syncytia with several interdigitating dendritic projections. Syncytia shrunk with condensed nuclear material and axon-like filaments characteristic for infected macrophages. VSV induced enlargement and necrotic lysis of all cell types. Early postinfection with HIV-1, electron microscopy revealed irreversible membrane fusion above cell nuclei, and transient fusion between filaments. Transient presence of coated vesicles containing intact HIV-1 particles, Birbeck granule-like structures of Langerhans cells, fibrillar-lamellar structures resembling hairy leukemia or Sézary cells were detected. Late postinfection, high proportion of HIV-1 bud from polarized cytoplasm was empty particle, while that bud and entrapped in cytoplasmic vacuoles contained two or multiple cores in a fused envelope. The effect of early gene products of HIV-1 on HTLV-I and C8166 cells might elicit their latent potentials for monocyte or interdigitating dendritic cells, while in the later phase HTLV-I products might alter HIV-1 virion assembly.
AIDS Research and Human Retroviruses | 1990
Joseph Ongrádi; Luca Ceccherini-Nelli; Mauro Pistello; Steven Specter; Mauro Bendinelli
Archives of Dermatology | 2000
Joseph Ongrádi; Krisztina Becker; Attila Horváth; Edit Hidvégi; Ilona Mezey
Orvosi Hetilap | 1999
Joseph Ongrádi; A. Csiszár; C. L. Maródi; J. Sólyom; A. Horváth; J. Menezes
International Journal of Immunopharmacology | 1991
John W. Hadden; Joseph Ongrádi; Steven Specter; David Nelson; Elba M. Hadden; Marina Sosa; Craig R. Monell; Mette Strand
Archive | 1990
Joseph Ongrádi; Luca Ceccherini-Nelli; E. Soldaini; Mauro Bendinelli; G. Conaldi; Steven Specter; H. Friedman
Orvosi Hetilap | 1999
Joseph Ongrádi; P. Miheller; A. Csiszár; J. Menezes; C. L. Maródi; L. Sréter; A. Horváth