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1.
Front Physiol ; 12: 706743, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912234

RESUMO

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombosis and pregnancy morbidity (PM) obstetric events together with persistent high titers of circulating antiphospholipid antibodies (aPL). Several mechanisms that explain the development of thrombosis and PM in APS include the association of aPL with alterations in the coagulation cascade and inflammatory events. Other mechanisms disturbing cellular homeostases, such as mitochondrial dysfunction, autophagy, and cell proliferation, have been described in other autoimmune diseases. Therefore, the objective of this study was to investigate the impact of aPL from different patient populations on endothelial cell mitochondrial function, activation of the mammalian target of rapamycin (mTOR) and autophagy pathways, and cellular growth. Using an in vitro model, human umbilical vein endothelial cells (HUVECs) were treated with polyclonal immunoglobulin G (IgG) purified from the serum of women with both PM and vascular thrombosis (PM/VT), with VT only (VT), or with PM and non-criteria aPL (seronegative-obstetric APS, SN-OAPS). We included IgG from women with PM without aPL (PM/aPL-) and healthy women with previous uncomplicated pregnancies (normal human serum, NHS) as control groups. Mitochondrial function, mTOR activation, autophagy, and cell proliferation were evaluated by Western blotting, flow cytometry, and functional assays. IgG from women with PM/VT increased HUVEC mitochondrial hyperpolarization and activation of the mTOR and autophagic pathways, while IgG from patients with VT induced endothelial autophagy and cell proliferation in the absence of elevated mTOR activity or mitochondrial dysfunction. IgG from the SN-OAPS patient group had no effect on any of these HUVEC responses. In conclusion, aPL from women with PM and vascular events induce cellular stress evidenced by mitochondrial hyperpolarization and increased activation of the mTOR and autophagic pathways which may play a role in the pathogenesis of obstetric APS.

2.
Cell Microbiol ; 21(3): e12976, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30427108

RESUMO

Recognition and internalisation of intracellular pathogens by host cells is a multifactorial process, involving both stable and transient interactions. The plasticity of the host cell plasma membrane is fundamental in this infectious process. Here, the participation of macrophage lipid microdomains during adhesion and internalisation of the fungal pathogen Histoplasma capsulatum (Hc) was investigated. An increase in membrane lateral organisation, which is a characteristic of lipid microdomains, was observed during the first steps of Hc-macrophage interaction. Cholesterol enrichment in macrophage membranes around Hc contact regions and reduced levels of Hc-macrophage association after cholesterol removal also suggested the participation of lipid microdomains during Hc-macrophage interaction. Using optical tweezers to study cell-to-cell interactions, we showed that cholesterol depletion increased the time required for Hc adhesion. Additionally, fungal internalisation was significantly reduced under these conditions. Moreover, macrophages treated with the ceramide-glucosyltransferase inhibitor (P4r) and macrophages with altered ganglioside synthesis (from B4galnt1-/- mice) showed a deficient ability to interact with Hc. Coincubation of oligo-GM1 and treatment with Cholera toxin Subunit B, which recognises the ganglioside GM1, also reduced Hc association. Although purified GM1 did not alter Hc binding, treatment with P4 significantly increased the time required for Hc binding to macrophages. The content of CD18 was displaced from lipid microdomains in B4galnt1-/- macrophages. In addition, macrophages with reduced CD18 expression (CD18low ) were associated with Hc at levels similar to wild-type cells. Finally, CD11b and CD18 colocalised with GM1 during Hc-macrophage interaction. Our results indicate that lipid rafts and particularly complex gangliosides that reside in lipid rafts stabilise Hc-macrophage adhesion and mediate efficient internalisation during histoplasmosis.


Assuntos
Adesão Celular , Endocitose , Histoplasma/imunologia , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Macrófagos/microbiologia , Microdomínios da Membrana/metabolismo , Animais , Linhagem Celular , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
J Infect Dis ; 219(1): 31-40, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30059980

RESUMO

Zika virus (ZIKV) has recently caused a large epidemic in the Americas that is associated with birth defects. Although ZIKV is primarily transmitted by Aedes mosquitoes, ZIKV RNA is detectable in blood and semen of infected individuals for weeks or months, during which sexual and other modes of transmission are possible. However, viral RNA is usually detectable longer than infectious virus is present. We determined the frequency of isolation of infectious virus from semen and serum samples prospectively obtained from a cohort of patients in Puerto Rico. We confirmed isolation of infectious virus on the basis of a tissue culture cytopathic effect, an increase in virus genome copy equivalents (GCE), and positive results of immunofluorescence analysis; virus in infected cells was quantitated by flow cytometry. These criteria confirmed the presence of infectious virus in semen specimens from 8 of 97 patients for up to 38 days after initial detection when virus loads are >1.4 × 106 genome copy equivalents/mL. Two serum isolates were obtained from 296 patients. These findings can help guide important prevention guidelines for persons that may potentially be infectious and transmit ZIKV sexually.


Assuntos
RNA Viral/isolamento & purificação , Sêmen/virologia , Infecção por Zika virus/sangue , Zika virus/isolamento & purificação , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Feminino , Humanos , Masculino , Estudos Prospectivos , Porto Rico , RNA Viral/sangue , Manejo de Espécimes , Células Vero , Carga Viral , Replicação Viral , Zika virus/fisiologia
4.
Nat Commun ; 8(1): 1968, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29213074

RESUMO

Cryptococcus neoformans is an encapsulated fungal pathogen that causes cryptococcosis, which is a major opportunistic infection in immunosuppressed individuals. Mammalian ß-galactoside-binding protein Galectin-3 (Gal-3) modulates the host innate and adaptive immunity, and plays significant roles during microbial infections including some fungal diseases. Here we show that this protein plays a role also in C. neoformans infection. We find augmented Gal-3 serum levels in human and experimental infections, as well as in spleen, lung, and brain tissues of infected mice. Gal-3-deficient mice are more susceptible to cryptococcosis than WT animals, as demonstrated by the higher fungal burden and lower animal survival. In vitro experiments show that Gal-3 inhibits fungal growth and exerts a direct lytic effect on C. neoformans extracellular vesicles (EVs). Our results indicate a direct role for Gal-3 in antifungal immunity whereby this molecule affects the outcome of C. neoformans infection by inhibiting fungal growth and reducing EV stability, which in turn could benefit the host.


Assuntos
Antifúngicos/imunologia , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Criptococose/imunologia , Cryptococcus neoformans/efeitos dos fármacos , Galectina 3/imunologia , Galectina 3/farmacologia , Imunidade Adaptativa , Animais , Cápsulas Bacterianas/efeitos dos fármacos , Proteínas Sanguíneas , Encéfalo/imunologia , Criptococose/microbiologia , Cryptococcus neoformans/crescimento & desenvolvimento , Cryptococcus neoformans/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Galectina 3/sangue , Galectina 3/genética , Galectinas , Expressão Gênica , Humanos , Pulmão/imunologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Baço/imunologia
5.
P R Health Sci J ; 35(3): 134-41, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27623138

RESUMO

OBJECTIVE: A dimensional assessment model as a supplement to the diagnosis process could overcome the current pitfalls in classifying psychopathology in ethnic minorities. The aim of the study described herein was to examine a sample of Puerto Rican patients diagnosed with anxiety disorder in order to evaluate the psychometric properties of the specific scales that assess the following 3 domains: clinical symptoms, personality/trait, and affective style. METHODS: 80 subjects were recruited and interviewed using the Structured Clinical Interview for DSM-IV to identify the presence of anxiety disorders. Following this, various questionnaires assessing each proposed domain were administered to the participants. Reliability and validity of these questionnaires were examined using Cronbach's alpha and exploratory factor analysis. The effect of the individual items of the questionnaires on the overall reliability and validity was assessed using factor scores component matrix. RESULTS: Analyses revealed moderate to high reliability and validity scores within all 3 domains. The sample obtained moderate to high scores on the scales comprising clinical and personality/trait domains. CONCLUSION: The use of self-report scales in accordance with the proposed dimensional framework may be an effective way to supplement categorical diagnoses within the Hispanic population represented by this sample.


Assuntos
Ansiedade/diagnóstico , Ansiedade/psicologia , Testes Psicológicos , Adulto , Feminino , Humanos , Masculino , Psicometria , Autorrelato
6.
PLoS One ; 11(6): e0156983, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27310929

RESUMO

Quantitative analysis of the scientific literature is important for evaluating the evolution and state of science. To study how the density of biological literature has changed over the past two decades we visually inspected 1464 research articles related only to the biological sciences from ten scholarly journals (with average Impact Factors, IF, ranging from 3.8 to 32.1). By scoring the number of data items (tables and figures), density of composite figures (labeled panels per figure or PPF), as well as the number of authors, pages and references per research publication we calculated an Average Publishable Unit or APU for 1993, 2003, and 2013. The data show an overall increase in the average ± SD number of data items from 1993 to 2013 of approximately 7±3 to 14±11 and PPF ratio of 2±1 to 4±2 per article, suggesting that the APU has doubled in size over the past two decades. As expected, the increase in data items per article is mainly in the form of supplemental material, constituting 0 to 80% of the data items per publication in 2013, depending on the journal. The changes in the average number of pages (approx. 8±3 to 10±3), references (approx. 44±18 to 56±24) and authors (approx. 5±3 to 8±9) per article are also presented and discussed. The average number of data items, figure density and authors per publication are correlated with the journal's average IF. The increasing APU size over time is important when considering the value of research articles for life scientists and publishers, as well as, the implications of these increasing trends in the mechanisms and economics of scientific communication.


Assuntos
Disciplinas das Ciências Biológicas/tendências , Editoração/tendências , Ciência/tendências , Humanos , Publicações/tendências , Pesquisa/tendências
7.
Mol Phylogenet Evol ; 39(3): 855-64, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16442312

RESUMO

We used sequence variation in the mtDNA control-region and ND2 and cyt b genes to assess the systematics and biogeography of the five species of pupfish (Cyprinodon) on Hispaniola. These include four endemics, the relatively large-bodied Cyprinodon bondi, Cyprinodon nichollsi, and Cyprinodon sp., each from a separate lake in southwestern Hispaniola, and Cyprinodon higuey from a coastal lake in eastern Hispaniola. The fifth species consists of coastal populations referable to Cyprinodon variegatus riverendi. The results indicate that Hispaniola has been invaded by at least two forms, first by a late Pliocene progenitor of Cyprinodon variegatus ovinus and the large-bodied Hispaniolan species, and, more recently, by one or more ancestral forms allied with Cyprinodon variegatus variegatus and C. v. riverendi. Levels of divergence indicate that large expanses of open sea have not acted as long-term barriers to inter-island dispersal of cyprinodontiform fishes. This study, together with the molecular systematics of other insular Caribbean fishes, indicates that most insular groups originated from late Neogene dispersal from the mainland. The patterns of mtDNA variation in Cyprinodon showed little congruence with the species/subspecies taxonomy.


Assuntos
Peixes Listrados/classificação , Animais , DNA Mitocondrial/genética , Geografia , Peixes Listrados/genética , Polimorfismo de Fragmento de Restrição , Especificidade da Espécie , Índias Ocidentais
8.
Rev. cienc. adm. financ. segur. soc ; 10(2): 13-27, jul.-dic. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-403889

RESUMO

El objetivo de la investigación se centró en determinar el impacto cuali-cuantitativo que representa para la C.C.S.S. las incapacidades por enfermedad y maternidad, mediante la elaboración y comparación de indicadores que se obtuvieron de una base de datos e información recopilada, de los años 1998 hasta el 2001. Se establece en cuáles establecimientos, según nivel de complejidad, se presenta la mayor proporción de incapacidades por trabajador; así mismo en cuáles unidades de trabajo en el ámbito de toda la Institución se generan el mayor promedio de incapacidades por trabajador y los respectivos costos; por otra parte, se describen los diagnósticos más frecuentes por los que se incapacitan los trabajadores de la C.C.S.S. y los respectivos montos por subsidios pagados. Al final, se presentan una serie de recomendaciones a fin de disminuir y prevenir las incapacidades de los empleados de la institución; y además, superar algunas deficiencias con que cuenta el Sistema de Incapacidades de empleados de la C.C.S.S.


Assuntos
Humanos , Masculino , Feminino , Efeitos Psicossociais da Doença , Custos e Análise de Custo , Avaliação da Deficiência , Custos de Saúde para o Empregador , Impactos da Poluição na Saúde , Licença Parental/economia , Licença Médica , Previdência Social , Costa Rica , Previdência Social
9.
Plant Dis ; 86(12): 1402, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30818451

RESUMO

Orchid fleck virus (OFV), a tentative member of the family Rhabdoviridae, infects orchids in several countries. The virus is vectored worldwide by the mite Brevipalpus californicus (Banks) (Acari: Tenuipalpidae). Eleven plants of Oncidium spp. and one plant each of the genera Cymbidium and Maxillaria exhibiting numerous yellow flecks and necrotic ringspot lesions on leaves were collected in two private orchid collections in Costa Rica. Presence of OFV was assessed by plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA) using an antiserum developed against an OFV isolate in Japan (2), analyses of ultrathin sections of the host cell with transmission electron microscopy (TEM), and reverse transcription-polymerase chain reaction (RT-PCR) amplification using specific primers for the viral nucleocapsid gene (1). Eight of eleven Oncidium samples, and both Cymbidium and Maxillaria samples tested positive for OFV with PTA-ELISA having A405 values ranging from 3.9 to 14.6 times higher than negative controls. Thin sections from individual samples of Cymbidium, Oncidium, and Maxillaria revealed electron-lucent intranuclear viroplasm and short, rodlike particles (40 to 50 × 100 nm) in the nucleus or cytoplasm typical of OFV-infected cells. RT-PCR amplifications from one sample of each genera resulted in PCR-product bands of approximately 800 bp. The Cymbidium RT-PCR product was cloned into a pGEM-T-Easy expression vector and sequenced using an ABI 3700 sequencer. The 619-bp nucleocapsid gene consensus sequence had 98% homology with the OFV isolate 0023 identified in Germany (GenBank Accession No. AF343870) (1). However, it had only approximately 85% nucleocapsid gene homology with other OFV isolates available through GenBank, including those from countries geographically closer to Costa Rica, such as Brazil (1). To our knowledge, this is the first report of OFV infecting orchids in Costa Rica. References: (1) A. L. Blanchfield et al. J. Phytopathol. 149:713, 2001. (2) H. Kondo et al. Bull. Res. Inst. Bioresour. Okayama Univ. 4:149, 1996.

10.
Genet Mol Res ; 1(4): 282-97, 2002 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-14963819

RESUMO

(Co)variance components and genetic parameters were estimated for body weights of an elite Brahman herd under a designed, supervised management and genetic program, including strategic artificial insemination (AI). Restricted maximum likelihood methods were used with a univariate animal model for birth weight (BW) and a bivariate model for weaning weight (205-day weight, 205W) and 18-month weight (548-day weight, 548W). Models included random animal direct and maternal genetic effects, maternal permanent environmental effect (c2), and sex-year-month of birth-age of dam and genetic group (identified and unidentified paternity), as fixed effects. Analysis A1 included all calves and analysis A2 included only those with identified sires. Of the 8,066 calves born, 36% were progeny of AI, 11% from single sire and 53% from multi-sire herds. They were born from 1985 to 1998, from 2559 dams and 146 sires (78 identified). Estimates of direct, maternal and total heritabilities from A1 for BW, 205W and 548W were: 0.23, 0.07 and 0.30; 0.08, 0.14 and 0.16; 0.16, 0.04 and 0.28, respectively. Corresponding estimates of direct maternal genetic correlations were 0.22, 0.07 and 0.86, and c2 estimates were 0.04, 0.14 and 0.04, respectively. Estimates of direct and maternal genetic, and permanent environmental correlations between 205W and 548W were: 0.66, 0.70 and 1.00. Variances and genetic parameters from A1 and A2 were, in general, very similar. Estimates of phenotypic, and direct and maternal genetic trends per year from A1 were: 0.393, 0.004 and 0.003 kg (BW), 3.367, 0.142 and 0.115 kg (205W), 1.813, 0.263 and 0.095 kg (548W). Estimates of direct and maternal genetic trends from A2 were: 0.033 and -0.002 kg (BW); 0.186 and 0.276 kg (205W); 0.471 and 0.136 kg (548W). The modern selection methods that have been used recently should be continued, with emphasis on the improvement of cow efficiency for sustainable beef production on floodable savanna combined with improved pasture.


Assuntos
Peso Corporal/genética , Bovinos/genética , Variação Genética , Fenótipo , Análise de Variância , Criação de Animais Domésticos , Animais , Peso ao Nascer , Bovinos/crescimento & desenvolvimento , Feminino , Inseminação Artificial/genética , Masculino , Modelos Genéticos , Característica Quantitativa Herdável , Desmame , Aumento de Peso/genética
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