76 research outputs found
Quantitative competitive reverse transcription polymerase chain reaction is not a useful method for quantification of CD4 and CD8 cell status during HIV infection
BACKGROUND: A polymerase chain reaction (PCR)-based method for quantitating CD4 and CD8 mRNA could provide a means of assessing immune status of AIDS patients and other immunologically compromised persons without requiring large blood draws, and could be exquisitely sensitive. Such a method would also be useful in assessing the immune status of patients retrospectively. RESULTS: Quantitative competitive reverse transcription PCR (QC-RT-PCR) assays were developed for measurement of CD4 and CD8 mRNA. Samples were obtained from HIV-positive and negative patients whose CD4 and CD8 counts had been determined via Flow Cytometry. The quantity of CD4 (n = 13) and CD8 (n = 28) mRNA standardized according to GAPDH mRNA quantities, all determined by QC-RT-PCR, were compared to cell number as determined by flow cytometry. There was no correlation between CD4 and CD8 cell counts and mRNA levels of CD4 and CD8 as determined by QC-RT-PCR. There is no correlation between CD4 and CD8 mRNA levels and the number of cells expressing these proteins on their surface. CONCLUSION: QC-RT-PCR, and related methodologies are not useful substitutes for assessment of CD4 and CD8 cell numbers in HIV-infected persons
OPENMODS 2.0 âInstrument Jamming Meetingâ report
Major achievements
The feedback provided by potential users on their needs was very much appreciated. They
underlined the importance of having:
â an easy to deploy instrument (i.e.: from small fishing boats);
â multi-parameter sensors in ONE device;
â less maintenance effort
and prioritized the variables to measure.
Although, there are technical limitations and different solutions and there is no one tool that
can do everything, which is low cost, has high resolution and low maintenance, the
outcomes of the platforms/sensors/communications working group meet the main
requirements that emerged.
Priority was given to:
â a platform that will operate in drifter mode which is extremely easy to deploy and
perfect for studies associated with search and rescue operations (another need that
has emerged). It also constantly guarantees the knowledge of the instrument position.
The platform can be easily converted into the moored mode.
â temperature and pressure sensors. The sensors will be low -cost with the idea to
replace them rather than calibrate them;
â LoRaWAN communications preferably with Bluetooth integration for the in-situ
download of the data
HIV-1 Pre-Integration Complexes Selectively Target Decondensed Chromatin in the Nuclear Periphery
Integration of the double-stranded DNA copy of the HIV-1 genome into host chromosomal DNA is a requirement for efficient viral replication. Integration preferentially occurs within active transcription units, however chromosomal site specificity does not correlate with any strong primary sequence. To investigate whether the nuclear architecture may affect viral integration we have developed an experimental system where HIV-1 viral particles can be visualized within the nuclear compartment. Fluorescently labeled HIV-1 virions were engineered by fusing integrase, the viral protein that catalyzes the integration reaction, to fluorescent proteins. Viral tests demonstrate that the infectivity of fluorescent virions, including the integration step, is not altered as compared to wild-type virus. 3-D confocal microscopy allowed a detailed analysis of the spatial and temporal distribution of the pre-integration complexes (PICs) within the nucleus at different moments following infection; the fluorescently labeled PICs preferentially distribute in decondensed areas of the chromatin with a striking positioning in the nuclear periphery, while heterochromatin regions are largely disfavored. These observations provide a first indication of how the nuclear architecture may initially orient the selection of retroviral integration sites
As licenciaturas na atualidade: nova crise?
Este artigo visa situar o debate atual sobre a crise nas licenciaturas, pontuando algumas circunstĂąncias histĂłricas tanto de afirmação e ampliação da escola como locus privilegiado do ensino no mundo moderno quanto da emergĂȘncia do sentimento de que ela nĂŁo cumpriu a promessa de formar cidadĂŁos autĂŽnomos, livres e iguais em direitos. Exemplifica essa crise com dados apurados pela PrĂł-Reitoria de Graduação (PROGRAD) e pelo Colegiado Especial de Licenciaturas da Universidade Federal Minas Gerais (UFMG) sobre a relação candidato/vaga nos seus Ășltimos 15 vestibulares. Esses dados apontam para um contĂnuo esvaziamento dos cursos de licenciatura, tanto no que se refere aos vestibulares quanto aos que se formam, mas optam por ocupaçÔes mais vantajosas economicamente. Isso traz questĂ”es relevantes para se pensar tanto a formação inicial quanto a formação continuada de professores, uma vez que, em decorrĂȘncia das vertiginosas mudanças na vida social contemporĂąnea, hĂĄ um descompasso entre os processos de formação e a emergĂȘncia de novas demandas para as quais o corpo docente parece sempre estar despreparado para assumir
A MSFD complementary approach for the assessment of pressures, knowledge and data gaps in Southern European Seas : the PERSEUS experience
PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern
European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good
Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary
approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge
gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal
areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also
independently performed. The comparison between meta-analysis results and IAs shows similarities
for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food
web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification
of additional research themes targeting research topics that are requested to the achievement of GES.
2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license.peer-reviewe
Role of PSIP1/LEDGF/p75 in lentiviral infectivity and integration targeting
To replicate, lentiviruses such as HIV must integrate DNA copies of their RNA genomes into host cell chromosomes. Lentiviral integration is favored in active transcription units, which allows efficient viral gene expression after integration, but the mechanisms directing integration targeting are incompletely understood. A cellular protein, PSIP1/LEDGF/p75, binds tightly to the lentiviral-encoded integrase protein (IN), and has been reported to be important for HIV infectivity and integration targeting.Here we report studies of lentiviral integration targeting in 1) human cells with intensified RNAi knockdowns of PSIP1/LEDGF/p75, and 2) murine cells with homozygous gene trap mutations in the PSIP1/LEDGF/p75 locus. Infections with vectors derived from equine infections anemia virus (EIAV) and HIV were compared. Integration acceptor sites were analyzed by DNA bar coding and pyrosequencing.In both PSIP1/LEDGF/p75-depleted cell lines, reductions were seen in lentiviral infectivity compared to controls. For the human cells, integration was reduced in transcription units in the knockdowns, and this reduction was greater than in our previous studies of human cells less completely depleted for PSIP1/LEDGF/p75. For the homozygous mutant mouse cells, similar reductions in integration in transcription units were seen, paralleling a previous study of a different mutant mouse line. Integration did not become random, however-integration in transcription units in both cell types was still favored, though to a reduced degree. New trends also appeared, including favored integration near CpG islands. In addition, we carried out a bioinformatic study of 15 HIV integration site data sets in different cell types, which showed that the frequency of integration in transcription units was correlated with the cell-type specific levels of PSIP1/LEDGF/p75 expression
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