1,180 research outputs found

    Integrated calcareous plankton biostratigraphy of selected Miocene successions in the Northern Calabria (Italy)

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    An integrated calcareous plankton biostratigraphic approach on six sections cropping out in Northern Calabria allowed to define a revised chronostratigraphic framework for Tortonian-Messinian deposits. Four sections have been investigated in the Amantea Basin (Timpone Napoli, Vallone Salina, Case Vespano, and Cozzo Salice) and two in the Rossano Basin (Vallone Casino and Cozzo Sant'Isidoro). Biostratigraphic analyses have been based on quantitative counting of planktonic foraminifers and semiquantitative counting of nannofossils. The Timpone Napoli and Vallone Salina sections are Late Tortonian in age and referable to the Globorotalia suterae Zone. In terms of nannofossils zonal scheme these sections fall within the Coccolithus pelagicus - Amaurolithus primus Zones. The Case Vespano and Cozzo Salice sections can be ascribed to the Messinian. The Case Vespano section is wholly characterized by the common occurrence of Globorotalia miotumida group. The co-occurrence of Amarolithus delicatus, A. cf. amplificus,. and Reticulofenestra rotaria confirms a Messinian age. The lower part of the Cozzo Salice section is rich of Gt. conomiozea, while its middle and the upper part is barren in planktonic foraminifers. In the Vallone Casino and Cozzo Sant'Isidoro sections the Tortonian-Messinian boundary corresponds to the first occurrence (FO) of Gt. miotumida group (sensu Hilgen et al., 2000), just above the first occurrence of A. delicatus. Biostratigraphic data allowed to correlate the Messinian silty layers of Amantea Basin with the coeval diatomitic beds of Rossano Basin indicating that the two areas, during the Messinian, had different paleogeographic and palaeoecological evolution

    Blood–brain barrier impairment in patients living with hiv: Predictors and associated biomarkers

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    Despite the substantial changes resulting from the introduction of combination antiretroviral therapy (cART), the prevalence of HIV-associated neurocognitive disorders (HAND) remains substantial. Blood–brain barrier impairment (BBBi) is a frequent feature in people living with HIV (PLWH) and it may persist despite effective antiretroviral treatment. A cross-sectional study was performed in PLWH who underwent lumbar puncture for clinical reasons or research protocols and several cerebrospinal fluid biomarkers were studied. BBBi was defined as cerebrospinal fluid-to-serum albumin ratio (CSAR) >6.5 (<40 years) or >8 (>40 years). We included 464 participants: 147 cART-naïve and 317 on cART. Male sex was prevalent in both groups (72.1% and 72.2% respectively); median age was 44 (38–52) years in naïve and 49 (43–57) years in treated subjects. BBBi was observed in 35.4% naïve and in 22.7% treated participants; the use of integrase inhibitors was associated with a lower prevalence (18.3 vs. 30.9%, p = 0.050). At multivariate binary logistic regression (including age and sex) nadir CD4 cell count (p = 0.034), presence of central nervous system (CNS) opportunistic infections (p = 0.024) and cerebrospinal fluid (CSF) HIV RNA (p = 0.002) in naïve participants and male sex (p = 0.021), a history of CNS opportunistic infections (p = 0.001) and CSF HIV RNA (p = 0.034) in treated patients were independently associated with BBBi. CSF cells and neopterin were significantly higher in participants with BBBi. BBBi was prevalent in naïve and treated PLWH and it was associated with CSF HIV RNA and neopterin. Systemic control of viral replication seems to be essential for BBB integrity while sex and treatment influence need further studies
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