Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication.
The aim of the study was to examine the prevalence of primary peritoneal serous papillary carcinoma (PPSPC) as compared with ovarian serous papillary cancer (OSPC), and to study the clinicopathologic features and the frequency of germline BRCA1 and BRCA2 mutations in patients with PPSPC compared with those with OSPC. The study group included 28 cases of PPSPC. The comparison group included 35 female patients with OSPC, matched for stage, grade, and histologic subtype. All tumors were staged as either IIIB, IIIC or IV according to FIGO criteria. The patient characteristics, family and personal history of malignancies, the prevalence of germline BRCA mutations, clinicopathologic findings, presenting symptoms, pre- and intraoperative findings, and survival were compared in a matched-case retrospective study comparing patients with PPSPC vs. those with OSPC. Statistical analysis was made using Student's t-test, Chi-square, Wilcoxon, Kaplan-Meier and log-rank methods. Women with PPSPC had a significantly earlier menarche (P = 0.037) and a higher number or births (P = 0.03) than women with OSPC. No difference was found with regard to the prevalence of germline BRCA mutations in women with PPSPC compared with women with OSPC (7.1% vs. 25.7%). There was a significant increase (P = 0.02) in the incidence of abdominal distension as reported by PPSPC (64%) vs. OSPC patients (26%). Significantly more women with PPSPC than with OSPC presented with clinical ascites (P = 0.0001) and without palpable pelvic mass (P = 0.000001). On exploratory laparotomy, significantly more women with PPSPC than with OSPC had a minimal disease in the pelvis (P = 0.0087). Three-year survival analysis demonstrated a significantly worse survival rate for the PPSPC group than for the OSPC group (P = 0.017). A significant increase in the prevalence of PPSPC compared with OSPC was observed during the study years (P = 0.00001). We concluded that PPSPC and OSPC might be two distinct cancers, presenting a new epidemiologic trend regarding the increased incidence of PPSPC.
The roles of Type I interferon (IFN) in human immunodeficiency virus Type 1 (HIV-1) neuropathogenesis are poorly understood; both protective and deleterious effects of IFN signaling have been described. We used genetically modified mice deficient in the Type I IFN receptor (IFNRKO) to analyze the progress of HIV-1 brain infection and neuropathogenesis in the absence of IFN signaling. IFNRKO and wild-type (WT) mice on the 129xSv/Ev or C57BL/6 strain backgrounds were infected systemically with EcoHIV, a chimeric HIV-1 that productively infects mice. IFNRKO mice showed higher HIV-1 expression in spleen and peritoneal macrophages and greater virus infiltration into the brain compared to WT mice. Neuropathogenesis was studied by histopathological, immunohistochemical, immunofluorescence, and polymerase chain reaction analyses of brain tissues after the virus was inoculated into the brain by stereotaxic intracerebral injection. Both IFNRKO and WT mice showed readily detectable HIV-1 and brain lesions, including microglial activation, astrocytosis, and increased expression of genes coding for inflammatory cytokines and chemokines typical of human HIV-1 brain disease. Parameters of HIV-1 neuropathogenesis, including HIV-1 expression in microglia/macrophages, were significantly greater in IFNRKO than in WT mice. Our results show unequivocally that Type I IFN signaling and responses limit HIV-1 infection and pathogenesis in the brains of mice.
SUMMARYThe ability of sponges to feed in diverse (including oligotrophic) ecosystems significantly contributes to their ubiquitous aquatic distribution. It was hypothesized that sponges that harbour small amounts of symbiotic bacteria in their mass feed mainly on particulate organic matter (POM). We examined the nearly symbiont-free (by microscopic observation) filter-feeding Red Sea sponge Negombata magnifica in order to: (a) study removal efficiency of naturally occurring organic particles, (b) measure the total amount of absorbed particulate organic carbon ( g -1 (WM) nitrogen was excreted as total ammonia nitrogen (TAN); however, nitrogen allowance should be higher because more nitrogen is deposited for sponge biomass during growth. It is hypothesized that the discrepancy in the nutritional requirements should be covered by the sponge absorbing carbon and nitrogen from sources that are not dealt with in the present research, such as dissolved organic carbon and nitrogen. This study highlights the significance of detritus as a carbon source, and prokaryotes as a PON source in sponge feeding.
Aberrant excitatory neurotransmission associated with overproduction of glutamate has been implicated in the development of HIV-associated neurocognitive disorders (HAND). The glutamine antagonist 6-diazo-5-oxo-L-norleucine (DON, 14) attenuates glutamate synthesis in HIV-infected microglia/macrophages, offering therapeutic potential for HAND. We show that 14 prevents manifestation of spatial memory deficits in chimeric EcoHIV-infected mice, a model of HAND. 14 is not clinically available, however, because its development was hampered by peripheral toxicities. We describe the synthesis of several substituted N-(pivaloyloxy)alkoxy-carbonyl prodrugs of 14 designed to circulate inert in plasma and be taken up and biotransformed to 14 in the brain. The lead prodrug, isopropyl 6-diazo-5-oxo-2-(((phenyl(pivaloyloxy)methoxy)-carbonyl)amino)hexanoate (13d), was stable in swine and human plasma but liberated 14 in swine brain homogenate. When dosed systemically in swine, 13d provided a 15-fold enhanced CSF-to-plasma ratio and a 9-fold enhanced brain-to-plasma ratio relative to 14, opening a possible clinical path for the treatment of HAND.
Abstract-The removal efficiency of viral particles by the coral reef sponge Negombata magnifica was measured. Virus particles were removed by the sponge at an average efficiency of 23.3% 6 2.9%. Significant amounts of nutrients are transported from virus particles to higher trophic levels via sponges.
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