2,837 research outputs found

    Características clínico-epidemiológicas de crianças com toxoplasmose atendidas no Hospital Infantil Joana de Gusmão

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    Trabalho de ConclusĂŁo de Curso - Universidade Federal de Santa Catarina. Curso de Medicina. Departamento de Pediatria

    The role of the rhesus macaque (macaca mulatta) apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3) in lentiviral replication and persistence

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    SHIV infections in rhesus macaques have been used to extensively study accessory proteins of HIV-1 involved in pathogenesis as well as in vaccine development. All primate lentiviruses encode for a Vif (virion infectivity factor) protein, which is required for HIV-1 replication in primary CD4+ T cells and macrophages. The Vif protein interacts with APOBEC3 (A3) proteins promoting their accelerated degradation by the 26S proteosome. Sequence analysis of Vif proteins from different lentiviruses revealed that there are two highly conserved domains in the carboxyl terminus that are required for recruitment of the of the Vif-CBF-β-Cul5/Elongin B/C/Rbx-1 E3 ubiquitin ligase complex. These domains are the viral BC box, SLQ(Y/F)LAL, and Zn2+ binding (H-X5-C-X17-18-C-X3-5-H; HCCH) motifs. Previous cell culture studies have shown that the introduction of amino acid substitutions into the SLQ(Y/F)LA motif resulted in decreased binding of Vif to Elongin C, while substitutions into the HCCH motif prevented the interaction of Vif with Cullin 5. In this first study, we introduced two amino acid changes in the highly conserved SLQYLA domain (S147A, L148A; AAQYLA) of the SIV Vif protein in SHIV. In vitro, the resulting virus, SHIVVifAAQYLA, replicated in A3G negative CEM-SS cells but failed to replicate in A3G positive CEM cells. We also showed that hA3G was incorporated into the virion. Following these in vitro studies, SHIVVifAAQYLA was inoculated into three rhesus macaques, which were followed for over six months to assess various viral and immunological factors throughout the duration of infection. All three macaques did not develop significant CD4+ T cell loss over the course of infection, had plasma viral loads that were over 100-fold lower than macaques inoculated with parental SHIVKU-1bMC33, and developed no histological lesions in various lymphoid tissues, and developed immunoprecipitating antibodies. DNA and RT-PCR analysis revealed that only a select number of tissues were infected with virus, while sequence analysis of PBMC and select tissue DNA (at necropsy) showed that the site-directed changes were stable during the first three weeks after inoculation but thereafter the S147A amino acid substitution changed to a threonine in two of the three macaques. However, the L148A substitution remained stale in the vif amplified from the PBMC and select tissues at necropsy in all three macaques. Extensive sequence analysis of the vif, vpu, nef, and env genes revealed a increased number of G-to-A mutations in the genes amplified from macaques inoculated with SHIVVifAAQYLA. The majority of these mutations (>85%) were in the context of 5'-T85%) were in the context of 5'-TC (minus strand) and not 3'-CC, suggesting that one or more of the rhesus A3 proteins may be responsible for the observed mutational patterns. To determine if infectious virus was present in the plasma at necropsy, plasma from the three macaques inoculated with SHIVVifAAQYLA were pooled and intravenously inoculated into a naïve macaque. This macaque maintained its levels of circulating CD4+ T cells throughout the duration of infection, maintained viral loads below the limits of detection, and did not produce immunoprecipitating antibodies. However, gag was present in the DNA and RNA isolated from PBMC throughout infection and in select tissues at necropsy. The results from this first study showed for the first time the importance of the SLYQLA domain in vivo in viral pathogenesis. It also showed that mutations in vif could lead to a persistent infection in rhesus macaques resulting in the accumulation of G-to-A substitutions in the viral genome. In the second study, we used the SHIV/macaque model of infection to compare the replication and pathogenicity of SHIVs that express a Vif protein in which the entire SLQYLA (SHIVVif5A) or HCCH (SHIVVifHCCH(-)) domains were substituted with alanine residues. Each virus was inoculated into three rhesus macaques where various viral and immunological parameters were followed for six months. Our in vitro results indicate that in the presence of these mutant Vif viruses, rhA3G is incorporated into the virion, stably expressed, restricts, and accumulates G-to-A substitutions (plus strand) in the nef,Italics/> gene of the mutated viral genomes. gene of the mutated viral genomes. In vivo, all macaques maintained a stable level of circulating CD4+ T cells, developed low viral burdens, maintained engineered mutations, yielded no histological lesions, and developed immunoprecipitating antibodies by 12 weeks post-inoculation. However, the production of viral RNA only persisted in macaques inoculated with SHIVVifHCCH(-). The analysis of vif sequences amplified from PBMC DNA between weeks 0-16 during SHIVVifHCCH(-) infection revealed an increased number of G-to-A substitutions that increased with time in two of the three macaques. Sequence analysis of nef and vpu from the small intestine (ileum), thymus, and the spleen showed G-to-A substitutions in nef genes isolated from macaques inoculated with SHIVVifHCCH(-). Macaques inoculated with SHIVVif5A effectively controlled the virus three weeks post-inoculation and no viral sequences could be amplified from tissue DNA. These studies showed that the SLQYLA and HCCH domains are critical for viral pathogenesis in vivo and that there may exist APOBEC3 negative reservoirs in the rhesus macaque that allow for low levels of viral replication and persistence but not disease. Therefore, this study suggests that mutations targeted to one or more functional conserved domains within the Vif protein may limit viral replication and generate an effective immune response leading to the "self-inactivation" of the virus by the activities of various APOBEC3 proteins resulting in a possible live-attenuated vaccine candidate. The APOBEC3 family of restriction factors has been shown to inhibit certain retroviruses and retroelements. The APOBEC3 family in humans is comprised of seven cytidine deaminases (A3A, A3B, A3C, A3D, A3F, A3G, and A3H) that catalyze the deamination of cytidine to uracil on single-stranded DNA or RNA. While the human APOBEC3 repertoire has been extensively studied, the full complement of these proteins in the rhesus macaque remains unknown. Sequencing of the rhesus macaque genome has led to the identification of the rhesus homologues A3B, A3C, A3D, A3F, A3G, and A3H. Finally, we identified a human A3A (hA3A) homologue in the rhesus macaque (rhA3A) and presents evidence that both the human and rhesus Apobec3 genes are orthologous. We show that rhA3A is highly expressed in activated CD4+ T cells, widely expressed in both the visceral and central nervous system tissues of the rhesus macaque, and is degraded in the presence of the human immunodeficiency virus (HIV-1) and simian-human immunodeficiency virus (SHIV) genomes in a Vif-dependent manner. Our results also indicate that rhA3A reduced the level of infectious SHIVΔvif by approximately 20-fold and HIV-1Δvif by 3-fold. Human and monkey A3A amino acid sequences are 81% homologous and can be distinguished by a three amino acid indel located between residues 27-30. When these residues were deleted from rhA3A (rhA3AΔSVR), the antiviral activity of rhA3A was abolished suggesting that these residues are critical for lentivirus inhibition. Select APOBEC3 proteins are incorporated into the virion and can inhibit reverse transcription and/or induce G-to-A hypermutation in nascent reverse transcripts in the next target cell. Previous studies revealed that rhA3G is incorporated into SHIVΔvif virions and exerts its antiviral activity in target cells by an increase in cytidine deamination of newly synthesized minus-strand viral DNA from cytosines to uracils, leading to G-to-A substitutions (plus strand) in the viral genome. We were able to detect the incorporation of rhA3A into SHIVΔvif and to a lesser extent in SHIV virions; however, we were unable to detect the incorporation of rhA3A into either HIV-1 or HIV-1Δvif virions. Even though rhA3A is incorporated into SHIVΔvif virions and potently restricts SHIVΔvif similar to rhA3G, rhA3A produced an approximately 5-fold decrease in the number of G-to-A mutations compared to rhA3G. Unlike hA3A, rhA3A did not inhibit adeno-associated virus 2 (AAV-2) replication and L1 retrotransposition. This data suggests for the first time an evolutionary switch in primate A3A virus specificity and provides evidence that a primate A3A protein can inhibit lentiviral replication

    Understanding Concept Identification as Consistent Data Clustering Across Multiple Feature Spaces

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    Identifying meaningful concepts in large data sets can provide valuable insights into engineering design problems. Concept identification aims at identifying non-overlapping groups of design instances that are similar in a joint space of all features, but which are also similar when considering only subsets of features. These subsets usually comprise features that characterize a design with respect to one specific context, for example, constructive design parameters, performance values, or operation modes. It is desirable to evaluate the quality of design concepts by considering several of these feature subsets in isolation. In particular, meaningful concepts should not only identify dense, well separated groups of data instances, but also provide non-overlapping groups of data that persist when considering pre-defined feature subsets separately. In this work, we propose to view concept identification as a special form of clustering algorithm with a broad range of potential applications beyond engineering design. To illustrate the differences between concept identification and classical clustering algorithms, we apply a recently proposed concept identification algorithm to two synthetic data sets and show the differences in identified solutions. In addition, we introduce the mutual information measure as a metric to evaluate whether solutions return consistent clusters across relevant subsets. To support the novel understanding of concept identification, we consider a simulated data set from a decision-making problem in the energy management domain and show that the identified clusters are more interpretable with respect to relevant feature subsets than clusters found by common clustering algorithms and are thus more suitable to support a decision maker.Comment: 10 pages, 6 figures, to be published in proceedings of 2022 IEEE International Conference on Data Mining Workshops (ICDMW

    Evaluation of the Light-Sensitive Cytotoxicity of Hypericum perforatum Extracts, Fractions, and Pure Compounds

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    Hypericum perforatum (Hp) is known for possessing antidepressant and antiviral activities. Despite its use as an alternative to conventional antidepressants, the identification of the cytotoxic chemicals derived from this herb is incomplete. In this study, the cytotoxicity of Hp extracts prepared in solvents ranging in polarity, fractions of one extract, and purified compounds were examined in three cell lines. All extracts exhibited significant cytotoxicity; those prepared in ethanol (no hyperforin, 3.6 ÎĽM hypericin, and 134.6 ÎĽM flavonoids) showed between 7.7 and 77.4% cell survival (p \u3c 0.0001 and 0.01), whereas the chloroform and hexane extracts (hyperforin, hypericin, and flavonoids not detected) showed approximately 9.0 (p \u3c 0.0001) and 4.0% (p \u3c 0.0001) survival. Light-sensitive toxicity was observed primarily with the ethanol extracts sequentially extracted following removal of material extracted in either chloroform or hexane. The absence of light-sensitive toxicity with the Hp extracts suggests that the hypericins were not playing a prominent role in the toxicity of the extracts

    uPA and PAI-1 as biomarkers in breast cancer: validated for clinical use in level-of-evidence-1 studies

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    Urokinase plasminogen activator (uPA) is an extracellular matrix-degrading protease involved in cancer invasion and metastasis, interacting with plasminogen activator inhibitor-1 (PAI-1), which was originally identified as a blood-derived endogenous fast-acting inhibitor of uPA. At concentrations found in tumor tissue, however, both PAI-1 and uPA promote tumor progression and metastasis. Consistent with the causative role of uPA and PAI-1 in cancer dissemination, several retrospective and prospective studies have shown that elevated levels of uPA and PAI-1 in breast tumor tissue are statistically independent and potent predictors of poor patient outcome, including adverse outcome in the subset of breast cancer patients with lymph node-negative disease. In addition to being prognostic, high levels of uPA and PAI-1 have been shown to predict benefit from adjuvant chemotherapy in patients with early breast cancer. The unique clinical utility of uPA/PAI-1 as prognostic biomarkers in lymph node-negative breast cancer has been confirmed in two independent level-of-evidence-1 studies (that is, in a randomized prospective clinical trial in which the biomarker evaluation was the primary purpose of the trial and in a pooled analysis of individual data from retrospective and prospective studies). Thus, uPA and PAI-1 are among the best validated prognostic biomarkers currently available for lymph node-negative breast cancer, their main utility being the identification of lymph node-negative patients who have HER-2-negative tumors and who can be safely spared the toxicity and costs of adjuvant chemotherapy. Recently, a phase II clinical trial using the low-molecular-weight uPA inhibitor WX-671 reported activity in metastatic breast cancer

    uPA and PAI-1 as biomarkers in breast cancer: validated for clinical use in level-of-evidence-1 studies

    Get PDF
    Urokinase plasminogen activator (uPA) is an extracellular matrix-degrading protease involved in cancer invasion and metastasis, interacting with plasminogen activator inhibitor-1 (PAI-1), which was originally identified as a blood-derived endogenous fast-acting inhibitor of uPA. At concentrations found in tumor tissue, however, both PAI-1 and uPA promote tumor progression and metastasis. Consistent with the causative role of uPA and PAI-1 in cancer dissemination, several retrospective and prospective studies have shown that elevated levels of uPA and PAI-1 in breast tumor tissue are statistically independent and potent predictors of poor patient outcome, including adverse outcome in the subset of breast cancer patients with lymph node-negative disease. In addition to being prognostic, high levels of uPA and PAI-1 have been shown to predict benefit from adjuvant chemotherapy in patients with early breast cancer. The unique clinical utility of uPA/PAI-1 as prognostic biomarkers in lymph node-negative breast cancer has been confirmed in two independent level-of-evidence-1 studies (that is, in a randomized prospective clinical trial in which the biomarker evaluation was the primary purpose of the trial and in a pooled analysis of individual data from retrospective and prospective studies). Thus, uPA and PAI-1 are among the best validated prognostic biomarkers currently available for lymph node-negative breast cancer, their main utility being the identification of lymph node-negative patients who have HER-2-negative tumors and who can be safely spared the toxicity and costs of adjuvant chemotherapy. Recently, a phase II clinical trial using the low-molecular-weight uPA inhibitor WX-671 reported activity in metastatic breast cancer

    OS INCENTIVOS FISCAIS E O PRINCĂŤPIO DO PROTETOR-RECEBEDOR.

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    O meio ambiente enquanto direito fundamental, previsto constitucionalmente, essencial a efetivação de outros direitos fundamentais, como a dignidade da pessoa humana, cada vez mais atingido pelos crescentes impactos decorrentes da exploração humana, tem fomentado a busca pelo desenvolvimento econômico e consumo sustentável. Políticas públicas voltadas a mudança de comportamento atendem ao princípio do protetor-recebedor que busca incentivar aquele que cuida, zela, elimina ou reduz os impactos da sua atividade ao meio ambiente. Os incentivos fiscais tem sido grandes sinalizadores desta mudança, no cenário nacional e internacional, na concessão de benefícios econômicos destinados ao protetor-recebedor, especialmente voltados ao consumo e desenvolvimento sustentável

    The extended gentle caesarean section protocol-expanding the scope and adding value for the family: a cross-sectional study.

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    PURPOSE In Switzerland, about one in three children is born by caesarean section (CS). For many women, this means a restricted birth experience, limited observation of the birth process and a restricted involvement. We evaluated an extended gentle CS protocol, which offered early intraoperative skin-to-skin contact and the possibility of observing the delivery of the baby from the abdomen through a transparent drape. METHODS This is a cross-sectional study incorporating data from a purposely tailored questionnaire and clinical routine data. The extended gentle CS protocol was compared with the gentle CS, which does not allow the possibility of observing the delivery. Data were collected online and analysed by multivariable regression for quantitative data and content analysis for all text responses to open questions, respectively. RESULTS 193 women completed the questionnaire. Of these, 154 had a gentle CS and 39 had an extended gentle CS. Multivariable regression did not reveal a statistically significant difference for extended gentle CS with regard to satisfaction with childbirth, mother-to-child bonding, or breastfeeding duration. Nevertheless, early intraoperative skin-to-skin contact was associated with the fulfilment of birth expectations. Furthermore, most women who experienced an extended gentle CS would prefer the same procedure for any potential future CS. CONCLUSIONS Although our study showed no statistically significant difference in satisfaction from using a transparent drape, most women expressed a preference for this technique. We recommend that the option of an extended gentle CS should be offered to all women for whom CS is indicated

    Differential expression of exosomal microRNAs in prefrontal cortices of schizophrenia and bipolar disorder patients

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    Exosomes are cellular secretory vesicles containing microRNAs (miRNAs). Once secreted, exosomes are able to attach to recipient cells and release miRNAs potentially modulating the function of the recipient cell. We hypothesized that exosomal miRNA expression in brains of patients diagnosed with schizophrenia (SZ) and bipolar disorder (BD) might differ from controls, reflecting either disease-specific or common aberrations in SZ and BD patients. The sources of the analyzed samples included McLean 66 Cohort Collection (Harvard Brain Tissue Resource Center), BrainNet Europe II (BNE, a consortium of 18 brain banks across Europe) and Boston Medical Center (BMC). Exosomal miRNAs from frozen postmortem prefrontal cortices with well-preserved RNA were isolated and submitted to profiling by Luminex FLEXMAP 3D microfluidic device. Multiple statistical analyses of microarray data suggested that certain exosomal miRNAs were differentially expressed in SZ and BD subjects in comparison to controls. RT-PCR validation confirmed that two miRNAs, miR-497 in SZ samples and miR-29c in BD samples, have significantly increased expression when compared to control samples. These results warrant future studies to evaluate the potential of exosome-derived miRNAs to serve as biomarkers of SZ and BD
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