Search results for "Simian"

Gut germinal center regeneration and enhanced antiviral immunity by mesenchymal stem/stromal cells in SIV infection.

2021

Although antiretroviral therapy suppresses HIV replication, it does not eliminate viral reservoirs or restore damaged lymphoid tissue, posing obstacles to HIV eradication. Using the SIV model of AIDS, we investigated the effect of mesenchymal stem/stromal cell (MSC) infusions on gut mucosal recovery, antiviral immunity, and viral suppression and determined associated molecular/metabolic signatures. MSC administration to SIV-infected macaques resulted in viral reduction and heightened virus-specific responses. Marked clearance of SIV-positive cells from gut mucosal effector sites was correlated with robust regeneration of germinal centers, restoration of follicular B cells and T follicular h…

Viral entry, lipid rafts and caveosomes.

2005

Lipid rafts and caveolae are detergent-insoluble plasma membrane microdomains, involved in cellular endocytic processes and signalling. Several viruses, including a human pathogen, echovirus 1, and an extensively studied simian virus 40 utilize these domains for internalization into the host cells. Interaction of viruses with receptors on the cell surface triggers specific conformational changes of the virus particle and can give rise to signalling events, which determine the mechanisms of virus entry. After internalization via cell surface lipid rafts or caveolae, virus-containing vesicles can fuse with caveosomes, pre-existing cytoplasmic organelles, or dock on other intracellular organel…

Fonti, suggestioni e intersezioni classiche, tardoantiche e medievali nell’«Alda» di Guglielmo di Blois

2019

In questo saggio vengono studiate le fonti classiche, tardoantiche e medievali dell’«Alda», commedia elegiaca latina di Guglielmo di Blois (scritta verso il 1169-1170). In particolare, dopo una presentazione generale dell’opera e una rassegna critica degli studi e delle edizioni, ci si sofferma sulle suggestioni attinte a Terenzio, Virgilio, Orazio, Ovidio, Stazio, all’«Aegritudo Perdicae», Massimiano, Boezio, Ildeberto di Lavardin, ad alcune commedie elegiache del sec. XII (il «Geta» e l’«Aulularia» di Vitale di Blois, il «Pamphilus», la «Lidia» di Arnolfo d’Orléans) e alla tradizione novellistica “orientale” («Mischle Sendebar»). This essay is founded on the classical, late and medieval s…

Termination of transcription in an ‘in vitro’ system is dependent on a polyadenylation sequence

1991

Using HeLa cell nuclear extract as a source of the different transcription and polyadenylation factors and reverse transcription to analyze the levels of RNA 5' and 3' to the cleavage-polyadenylation site, an in vitro assay has been established to study polyadenylation coupled to transcription directed by different adenovirus promoters. The levels of transcription 5' and 3' to the cleavage site in the L3 polyadenylation region are practically the same as described previously, however, the level of transcription 3' to the cleavage site in the SV40 early polyadenylation region decreases immediately after the cleavage site indicating a termination of the transcription.

AIDS and the Central Nervous System: Examining Pathobiology and Testing Therapeutic Strategies in the SIV-Infected Rhesus Monkey

1993

Cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus

1993

The pattern of expression of GFAP immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (SIV). Blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. Strong GFAP immunoreactivity was found in astrocytic cells in both uninfected and SIV-infected juvenile macaque in the subpial cerebral cortex and in subcortical white matter, where GFAP-positive cells were abundant. GFAP staining of cortical layers 2-6 on the other hand was weak or absent in three uninfected contro…

Determination of DNA single strand breaks and selective DNA amplification by N-nitrodimethylamine and analogs, and estimation of the indicator cells'…

1986

N-nitrodimethylamine is metabolized oxidatively to N-nitrohydroxymethylmethylamine, which decomposes to yield formaldehyde and N-nitromethylamine. All four compounds and N-nitromethylamine were tested for their ability to induce DNA single strand breaks in hepatocytes and in SV 40-transformed Chinese hamster embryo cell lines. Only the two monoalkylnitramines were positive. They induced single strand breaks in hepatocytes, but were not effective in the other cells. Formaldehyde and N-nitrohydroxymethylmethylamine were toxic to the cells. None of the compounds tested was able to induce selective DNA amplification in the two transformed cell lines. Enzymes involved in drug metabolism were ass…

A neutralizing antibody against human DNA polymerase epsilon inhibits cellular but not SV40 DNA replication.

1999

The contribution of human DNA polymerase epsilon to nuclear DNA replication was studied. Antibody K18 that specifically inhibits DNA polymerase activity of human DNA polymerase epsilon in vitro significantly inhibits DNA synthesis both when microinjected into nuclei of exponentially growing human fibroblasts and in isolated HeLa cell nuclei. The capability of this neutralizing antibody to inhibit DNA synthesis in cells is comparable to that of monoclonal antibody SJK-132-20 against DNA polymerase alpha. Contrary to the antibody against DNA polymerase alpha, antibody K18 against DNA polymerase epsilon did not inhibit SV40 DNA replication in vitro. These results indicate that DNA polymerase e…

Flow cytometric investigation of neutrophil oxidative burst and apoptosis in physiological and pathological situations

2009

Flow cytometric analysis provides a rapid screen for abnormalities of polymorphonuclear neutrophils (PMN) function and reflect their behavior in vivo more accurately. This review summarizes the major fluorescent probes used to study PMN oxidative burst and apoptosis using flow cytometry (FCM). We also provide examples of FCM studies in physiological and pathological situations, illustrating the advantages of FCM for assessment of PMN oxidative burst and PMN apoptosis. These data point to the role of FCM in detecting primary immunodeficiencies such as IRAK4 deficiency and support the use of the assessment of the PMN oxidative burst for routine testing in patients with bacterial infections. W…

Cytopathologic and neurochemical correlates of progression to motor/cognitive impairment in SIV-infected rhesus monkeys.

1994

Neurochemical, pathologic, virologic, and histochemical correlates of simian immunodeficiency virus (SIV)-associated central nervous system (CNS) dysfunction were assessed serially or at necropsy in rhesus monkeys that exhibited motor and cognitive deficits after SIV infection. Some infected monkeys presented with signs of acquired immunodeficiency disease (AIDS) at the time of sacrifice. Seven of eight animals exhibited motor skill impairment which was associated with elevated quinolinic acid in cerebrospinal fluid (CSF). Examination of the brains revealed diffuse increases in glial fibrillary acidic protein immunoreacti vity in cerebral cortex in all animals, regardless of evidence of imm…