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1.
Cell ; 183(5): 1264-1281.e20, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33091337

RESUMO

The HLA-DR15 haplotype is the strongest genetic risk factor for multiple sclerosis (MS), but our understanding of how it contributes to MS is limited. Because autoreactive CD4+ T cells and B cells as antigen-presenting cells are involved in MS pathogenesis, we characterized the immunopeptidomes of the two HLA-DR15 allomorphs DR2a and DR2b of human primary B cells and monocytes, thymus, and MS brain tissue. Self-peptides from HLA-DR molecules, particularly from DR2a and DR2b themselves, are abundant on B cells and thymic antigen-presenting cells. Furthermore, we identified autoreactive CD4+ T cell clones that can cross-react with HLA-DR-derived self-peptides (HLA-DR-SPs), peptides from MS-associated foreign agents (Epstein-Barr virus and Akkermansia muciniphila), and autoantigens presented by DR2a and DR2b. Thus, both HLA-DR15 allomorphs jointly shape an autoreactive T cell repertoire by serving as antigen-presenting structures and epitope sources and by presenting the same foreign peptides and autoantigens to autoreactive CD4+ T cells in MS.


Assuntos
Subtipos Sorológicos de HLA-DR/imunologia , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Alelos , Antígenos/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Reações Cruzadas/imunologia , Feminino , Humanos , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Peptídeos/imunologia , Proteoma/metabolismo , Adulto Jovem
2.
J Phys Chem A ; 128(1): 10-19, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38159057

RESUMO

Silacyclohex-2-ene and 1,1-difluorosilacyclohex-2-ene have been synthesized, and the chirped-pulse, Fourier-transform microwave spectra of each have been observed and analyzed from 4.9 to 23.1 GHz. Quantum chemical calculations have been performed at the B3LYP-D3BJ/Def2TZVP level of theory and predict µa to be the largest dipole moment component with a significantly larger value in this component for 1,1-difluorosilacyclohex-2-ene. In accordance with this prediction, the spectra were predominantly a-type with the observation of a few b- and c-type transitions. The signal-to-noise ratio was adequate in both spectra to observe 29Si, 30Si, and all singly substituted 13C isotopologues in natural abundance. All spectra have been fit to a semirigid rotational Hamiltonian and are presented. Analysis of the physical meaning of the fitted parameters is explored and determined to hold for the rotational constants while being more empirical for the centrifugal distortion terms. Experimental structures of both molecules indicate that the quantum chemically calculated structures for the atoms in the ring are a very close depiction of the experimentally determined structures. The structures of each molecule are compared to similar molecules for context, where it is shown that both molecules possess a similar "half-chair" conformation to that of the all-carbon analogue, cyclohexene.

3.
Phys Chem Chem Phys ; 24(4): 2454-2464, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35022647

RESUMO

The molecules 1,1-difluorosilacyclopent-3-ene (3SiCPF2) and silacyclopent-3-ene (3SiCP) have been synthesized and studied using chirped pulse, Fourier transform microwave (CP-FTMW) spectroscopy. For 3SiCP this is the first ever microwave study of the molecule and, for 3SiCPF2, the spectra reported in this work have been combined with that of previous work in a global fit. The spectra of each contain splitting which has been fit using a Hamiltonian consisting of semirigid and Coriolis coupling parameters. A refit of the original 3SiCPF2 work was also carried out. All fits and approaches are reported. Analyses of the spectra provide evidence that the molecule is planar which is in agreement with the high-level calculations, but the source of the splitting in the spectra has not been determined.

4.
J Phys Chem A ; 124(40): 8254-8262, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-32915569

RESUMO

High-level theoretical CCSD/cc-pVTZ computations have been carried out to calculate the structures and ring-puckering potential energy functions (PEFs) for 1,1-difluorosilacyclopent-2-ene (2SiCPF2) and 1,1-dichlorosilacyclopent-2-ene (2SiCPCl2). The structure and PEF for 1,1-dibromosilacyclopent-2-ene (2SiCPBr2) were obtained by ab initio MP2/cc-pVTZ computations. The parent silacyclopent-2-ene (2SiCP) is puckered with a 49 cm-1 barrier to planarity, 2SiCPF2 has a planar ring system, 2SiCPCl2 has a calculated tiny 4 cm-1 barrier but is essentially planar, and the dibromide has a calculated barrier of 36 cm-1. Microwave spectra of seven isotopic species of 2SiCPF2 were recorded on a chirped pulse, Fourier transform microwave (CP-FTMW) spectrometer in the 6-18 GHz region. The a-type and b-type transitions were observed. The rotational constants and three quartic centrifugal distortion constants were determined for the parent, 29Si, 30Si, and all singly substituted 13C isotopologues in natural abundance. This allowed for the determination of the heavy-atom structure of the ring and showed the ring to be planar. The experimentally determined rotational constants and geometrical parameters agree very well with the theoretical values and confirm the planarity of the five-membered ring. A comparison of the PEFs for the silane and the three dihalides shows the silane to have the stiffest puckering motion and the dibromide to be the least rigid.

5.
Curr Heart Fail Rep ; 17(2): 34-42, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32112345

RESUMO

PURPOSE OF REVIEW: Heart failure with preserved ejection fraction (HFpEF) or diastolic heart failure (DHF) makes up more than half of all congestive heart failure presentations (CHF). With an ageing population, the case load and the financial burden is projected to increase, even to epidemic proportions. CHF hospitalizations add too much of the financial and infrastructure strain. Unlike systolic heart failure (SHF), much is still either uncertain or unknown. Specifically, in epidemiology, the disease burden is established; however, risk factors and pathophysiological associations are less clear; diagnostic tools are based on rigid parameters without the ability to accurately monitor treatments effects and disease progression; finally, therapeutics are similar to SHF but without prognostic data for efficacy. RECENT FINDINGS: The last several years have seen guidelines changing to account for greater epidemiological observations. Most of these remain general observation of shortness of breath symptom matched to static echocardiographic parameters. The introduction of exercise diastolic stress test has been welcome and warrants greater focus. HFpEF is likely to see new thinking in the coming decades. This review provides some of perspective on this topic.


Assuntos
Insuficiência Cardíaca Diastólica/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Ecocardiografia , Teste de Esforço , Insuficiência Cardíaca Diastólica/diagnóstico , Humanos
6.
Med Vet Entomol ; 33(1): 99-109, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30450832

RESUMO

A 2-year longitudinal study of enzyme-linked immunosorbent assay (ELISA) antibodies against Phlebotomus perniciosus and Phlebotomus papatasi (Diptera: Psychodidae) sandfly saliva was performed in 32 Beagle dogs treated preventively with an imidacloprid-permethrin topical insecticide in an endemic area in Spain. Dogs were grouped into three sandfly exposure groups according to the time of inclusion in the study. Assays analysed immunoglobulin G (IgG) against salivary gland homogenates (SGH) of both species and recombinant P. papatasi rSP32 and P. perniciosus rSP03B proteins in serum. The dogs were participating in a Leishmania infantum (Kinetoplastida: Trypanosomatidae) vaccine trial and were experimentally infected with the parasite in the second year. No dog acquired natural L. infantum infections during the first year, but most developed anti-saliva antibodies, and median log-transformed optical densities (LODs) were seasonal, mimicking those of local sandflies. This indicates that the repellent efficacy of the insecticide used is below 100%. Multi-level modelling of LODs revealed variability among dogs, autocorrelation and differences according to the salivary antigen and the dog's age. However, dog seroprevalence, estimated using pre-exposure LODs as cut-offs, was relatively low. This, and the fact that dogs did not become naturally infected with L. infantum, would support the efficacy and usefulness of this imidacloprid-permethrin topical insecticide in canine leishmaniasis control.


Assuntos
Anticorpos/efeitos dos fármacos , Cães/imunologia , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Permetrina/farmacologia , Phlebotomus/efeitos dos fármacos , Animais , Anticorpos/sangue , Biomarcadores/sangue , Feminino , Repelentes de Insetos/administração & dosagem , Estudos Longitudinais , Neonicotinoides/administração & dosagem , Nitrocompostos/administração & dosagem , Permetrina/administração & dosagem , Espanha
7.
Heart Lung Circ ; 24(6): 536-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25637942

RESUMO

Congestive Heart Failure (CHF) is an ambulatory care sensitive condition, associated with significant morbidity and mortality, rarely with cure. Outpatient based pharmacological management represents the main and most important aspect of care, and is usually lifelong. This narrative styled opinion review looks at the pharmacological agents recommended in the guidelines in context of the Northern Territory (NT) of Australia. We explore the concept of validity, a term used to describe the basis of standardising a particular trial or study and the population to which it is applicable. We aim to highlight the problems of the current guidelines based approach. We also present alternatives that could utilise the core principles from major trials, while incorporating regional considerations, which could benefit clients living in the NT and remote Australia.


Assuntos
Fármacos Cardiovasculares/administração & dosagem , Serviços de Saúde do Indígena/organização & administração , Insuficiência Cardíaca/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Consulta Remota/métodos , Austrália , Ensaios Clínicos como Assunto , Comorbidade , Medicina Baseada em Evidências , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Northern Territory , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes
8.
Br J Cancer ; 110(7): 1705-11, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24619071

RESUMO

BACKGROUND: Screening for bowel cancer using the guaiac faecal occult blood test offered by the NHS Bowel Cancer Screening Programme (BCSP) is taken up by 54% of the eligible population. Uptake ranges from 35% in the most to 61% in the least deprived areas. This study explores reasons for non-uptake of bowel cancer screening, and examines reasons for subsequent uptake among participants who had initially not taken part in screening. METHODS: Focus groups with a socio-economically diverse sample of participants were used to explore participants' experience of invitation to and non-uptake of bowel cancer screening. RESULTS: Participants described sampling faeces and storing faecal samples as broaching a cultural taboo, and causing shame. Completion of the test kit within the home rather than a formal health setting was considered unsettling and reduced perceived importance. Not knowing screening results was reported to be preferable to the implications of a positive screening result. Feeling well was associated with low perceived relevance of screening. Talking about bowel cancer screening with family and peers emerged as the key to subsequent participation in screening. CONCLUSIONS: Initiatives to normalise discussion about bowel cancer screening, to link the BCSP to general practice, and to simplify the test itself may lead to increased uptake across all social groups.


Assuntos
Detecção Precoce de Câncer , Neoplasias Intestinais/diagnóstico , Motivação , Aceitação pelo Paciente de Cuidados de Saúde , Participação do Paciente , Adulto , Idoso , Atitude Frente a Saúde , Detecção Precoce de Câncer/psicologia , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Grupos Focais , Guaiaco , Humanos , Neoplasias Intestinais/epidemiologia , Neoplasias Intestinais/psicologia , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Sangue Oculto , Participação do Paciente/psicologia , Participação do Paciente/estatística & dados numéricos , Pesquisa Qualitativa , Fatores Socioeconômicos
9.
J Virol ; 87(6): 3393-408, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23302880

RESUMO

JC polyomavirus (JCV) infection is highly prevalent and usually kept in a persistent state without clinical signs and symptoms. It is only during immunocompromise and especially impaired CD4(+) T cell function in the brain, as seen in AIDS patients or natalizumab-treated multiple sclerosis patients, that JCV may cause progressive multifocal leukoencephalopathy (PML), an often life-threatening brain disease. Since CD4(+) T cells likely play an important role in controlling JCV infection, we here describe the T cell response to JCV in a group of predominantly HLA-DR-heterozygotic healthy donors (HD) by using a series of overlapping 15-mer peptides spanning all JCV-encoded open reading frames. We identified immunodominant epitopes and compared T cell responses with anti-JCV VP1 antibody production and with the presence of urinary viral shedding. We observed positive JCV-specific T cell responses in 28.6% to 77.6%, humoral immune response in 42.6% to 89.4%, and urinary viral shedding in 36.4% to 45.5% of HD depending on the threshold. Four immunodominant peptides were mapped, and at least one immunogenic peptide per HLA-DRB1 allele was detected in DRB1*01(+), DRB1*07(+), DRB1*11(+), DRB1*13(+), DRB1*15(+), and DRB1*03(+) individuals. We show for the first time that JCV-specific T cell responses may be directed not only against JCV VP1 and large T antigen but also against all other JCV-encoded proteins. Heterozygotic DRB1*04:01(+) individuals showed very low T cell responses to JCV together with normal anti-VP1 antibody levels and no urinary viral shedding, indicating a dominant-negative effect of this allele on global JCV-directed T cell responses. Our data are potentially relevant for the development of vaccines against JCV.


Assuntos
Epitopos de Linfócito T/análise , Cadeias HLA-DRB1/imunologia , Vírus JC/imunologia , Proteoma/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Mapeamento de Epitopos , Feminino , Cadeias HLA-DRB1/genética , Humanos , Epitopos Imunodominantes/análise , Masculino , Pessoa de Meia-Idade , Urina/virologia , Eliminação de Partículas Virais
10.
Plant Cell Environ ; 37(1): 189-203, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23738980

RESUMO

A V-ATPase subunit A protein (VHA-A) transcript together with a variant (C793 to U), which introduces a stop codon truncating the subunit immediately downstream of its ATP binding site, was identified within a Fucus vesiculosus cDNA from a heavy metal contaminated site. This is intriguing because the VHA-A subunit is the crucial catalytic subunit responsible for the hydrolysis of ATP that drives ion transport underlying heavy metal detoxification pathways. We employed a chemiluminescent hybridization protection assay to quantify the proportion of both variants directly from mRNA while performing quantification of total transcript using Q-PCR. Polyclonal antisera raised against recombinant VHA-A facilitated simultaneous detection of parent and truncated VHA-A and revealed its cellular and subcellular localization. By exploiting laboratory exposures and samples from an environmental copper gradient, we showed that total VHA-A transcript and protein, together with levels of the truncated variant, were induced by copper. The absence of a genomic sequence representing the truncated variant suggests a RNA editing event causing the production of the truncated VHA-A. Based on these observations, we propose RNA editing as a novel molecular process underpinning VHA trafficking and intracellular sequestration of heavy metals under stress.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Algas/metabolismo , Cobre/metabolismo , Fucus/enzimologia , Edição de RNA , Adenosina Trifosfatases/genética , Proteínas de Algas/genética , Sequência de Aminoácidos , DNA Complementar/genética , Fucus/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica , Dados de Sequência Molecular , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA/genética , RNA/metabolismo , Proteínas Recombinantes , Alinhamento de Sequência
11.
Epidemiol Infect ; 142(1): 156-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23544849

RESUMO

Trypanosoma cruzi I, a discrete typing unit (DTU) found in human infections in Venezuela and other countries of the northern region of South America and in Central America, has been recently classified into five intra-DTU genotypes (Ia, Ib, Ic, Id, Ie) based on sequence polymorphisms found in the spliced leader intergenic region. In this paper we report the genotype identification of T. cruzi human isolates from one outbreak of acute orally acquired Chagas disease that occurred in a non-endemic region of Venezuela and from T. cruzi triatomine and rat isolates captured at a guava juice preparation site which was identified as the presumptive source of infection. The genotyping of all these isolates as TcId supports the view of a common source of infection in this oral Chagas disease outbreak through the ingestion of guava juice. Implications for clinical manifestations and dynamics of transmission cycles are discussed.


Assuntos
Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Surtos de Doenças , Genes de Protozoários , Trypanosoma cruzi/genética , Animais , Sequência de Bases , Bebidas/parasitologia , Doença de Chagas/transmissão , Genótipo , Técnicas de Genotipagem , Humanos , Dados de Sequência Molecular , Psidium , Ratos/parasitologia , Instituições Acadêmicas , Alinhamento de Sequência , Trypanosoma cruzi/classificação , Trypanosoma cruzi/isolamento & purificação , Venezuela/epidemiologia
12.
J Immunol ; 189(7): 3618-30, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22942431

RESUMO

Virus-specific CD4(+) T cells play a central role in control of viral pathogens including JC polyoma virus (JCV) infection. JCV is a ubiquitous small DNA virus that leads to persistent infection of humans with no clinical consequences. However, under circumstances of immunocompromise, it is able to cause an opportunistic and often fatal infection of the brain called progressive multifocal leukoencephalopathy (PML). PML has emerged as a serious adverse event in multiple sclerosis patients treated with the anti-VLA-4 mAb natalizumab, which selectively inhibits cell migration across the blood-brain barrier and the gut's vascular endothelium thus compromising immune surveillance in the CNS and gut. In a multiple sclerosis patient who developed PML under natalizumab treatment and a vigorous immune response against JCV after Ab washout, we had the unique opportunity to characterize in detail JCV-specific CD4(+) T cell clones from the infected tissue during acute viral infection. The in-depth analysis of 14 brain-infiltrating, JCV-specific CD4(+) T cell clones demonstrated that these cells use an unexpectedly broad spectrum of different strategies to mount an efficient JCV-specific immune response including TCR bias, HLA cross-restriction that increases avidity and influences in vivo expansion, and a combination of Th1 and Th1-2 functional phenotypes. The level of combinatorial diversity in TCR- and HLA-peptide interactions used by brain-infiltrating, JCV-specific CD4(+) T cells has not, to our knowledge, been reported before in humans for other viral infections and confirms the exceptional plasticity that characterizes virus-specific immune responses.


Assuntos
Encéfalo/imunologia , Linfócitos T CD4-Positivos/imunologia , Movimento Celular/imunologia , Rearranjo Gênico do Linfócito T , Antígenos HLA-D/metabolismo , Vírus JC/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Encéfalo/metabolismo , Encéfalo/virologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Movimento Celular/genética , Células Cultivadas , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/metabolismo , Antígenos HLA-D/genética , Humanos , Leucoencefalopatia Multifocal Progressiva/genética , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética
13.
Mediators Inflamm ; 2014: 418292, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24757283

RESUMO

Demethylating agent, 5-Azacytidine (5-Aza), has been shown to be active in treatment of myeloid malignancies. 5-Aza enhances anticancer immunity, by increasing expression of tumor-associated antigens. However, the impact of 5-Aza immune responses remains poorly understood. Here, T-cell mediated tumor immunity effects of 5-Aza, are investigated in vitro and in vivo. T-cells from healthy donors were treated with 5-Aza and analyzed by qRT-PCR and flow cytometry for changes in gene expression and phenotype. Functionality was assessed by a tumor lysis assay. Peripheral blood from patients treated with 5-Aza after alloSCT was monitored for changes in T-cell subpopulations. 5-Aza treatment resulted in a decrease in CD8+ T-cells, whereas CD4+ T-cells increased. Furthermore, numbers of IFN-γ + T-helper 1 cells (Th1) were reduced, while Treg-cells showed substantial increase. Additionally, CD8+ T-cells exhibited limited killing capacity against leukemic target cells. In vivo data confirm the increase of Treg compartment, while CD8+ T-effector cell numbers were reduced. 5-Aza treatment results in a shift from cytotoxic to regulatory T-cells with a functional phenotype and a major reduction in proinflammatory Th1-cells, indicating a strong inhibition of tumor-specific T-cell immunity by 5-Aza.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T Reguladores/citologia , Células Th1/citologia , Linhagem da Célula , Células HL-60 , Humanos , Inflamação , Células K562 , L-Lactato Desidrogenase/metabolismo , Leucemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fenótipo , Transplante de Células-Tronco , Transplante Homólogo
14.
Parasite Immunol ; 35(5-6): 180-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23473453

RESUMO

The enzyme indoleamine 2,3-dioxigenase (IDO) is critical for the regulation of immune responses in pro-tolerogenic antigen-presenting cell. To address the profile of immune responses associated with Chagas disease, we measured IDO activity of peripheral blood mononuclear cells from 168 chronic patients and 13 healthy donors. We found that IDO activity was increased in patients with Chagas disease when compared with controls. Moreover, the IDO activity of patients with Chagas disease in the symptomatic chronic phase, involving cardiac or digestive alterations, was higher than that detected in asymptomatic patients and correlated with the severity of the symptoms. Furthermore, benznidazole treatment induced a long-lasting decrease in IDO activity in symptomatic patients, reaching levels comparable with those of healthy donors. These results suggest that a pro-tolerogenic state is associated with the severity of Chagas disease and that benznidazole treatment is a valuable tool for breaking the parasite-driven immune tolerance in the symptomatic chronic phase of Chagas disease.


Assuntos
Doença de Chagas/tratamento farmacológico , Doença de Chagas/enzimologia , Indolamina-Pirrol 2,3,-Dioxigenase/sangue , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Adulto , Doença de Chagas/imunologia , Feminino , Humanos , Tolerância Imunológica , Leucócitos Mononucleares/enzimologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Mol Biol Rep ; 40(8): 4901-12, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23677712

RESUMO

Calcineurin B, the regulatory subunit of calcineurin, a serine/threonine protein phosphatase, is highly conserved throughout the evolutionary scale including trypanosomatids such as Trypanosoma cruzi, and Leishmania major. Thus, in these flagellates the protein is required for mammalian host cell invasion and virulence and stress responses. With the aim of determining the presence of calcineurin B in Trypanosoma rangeli, a non-virulent trypanosome for mammals, the respective gene was amplified by PCR, cloned and sequenced. Two sequences of 531 bp in length showing a nucleotide polymorphism (314A>C) were obtained in spite of a single-copy gene was revealed by Southern blot. These sequences, probably the alleles from the gene, showed a 79% of identity with those from T. cruzi and clustered as the sister group of this trypanosome species in a Maximum Parsimony analysis. Deduced amino acid sequence comparison with trypanosomatids and other organisms through the phylogenetic scale as well as the obtained protein structural homology model suggested the presence of the four potential EF-hand regions and the corresponding calcium binding sites of the last three of these domains. Having assessed the expression of this protein in T. rangeli epimastigotes, and taking into account the following facts: (i) calcineurin inhibitors have inhibitory effect on the in vitro replication of T. cruzi, (ii) L. major promastigote growth is inhibited by chelating agents, and (iii) T. rangeli does not seem to productively infect mammalian cells, it is hypothesized herein that the function of this protein in T. rangeli is required for epimastigote growth.


Assuntos
Calcineurina/genética , Sequência Conservada/genética , Estágios do Ciclo de Vida/fisiologia , Modelos Moleculares , Trypanosoma rangeli/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Calcineurina/química , Clonagem Molecular , Estágios do Ciclo de Vida/genética , Modelos Genéticos , Dados de Sequência Molecular , Oligonucleotídeos/genética , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência , Trypanosoma rangeli/crescimento & desenvolvimento
16.
J Appl Microbiol ; 115(1): 156-62, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23560745

RESUMO

AIMS: Nine commercial DNA extraction kits were evaluated for the isolation of DNA from 10-fold serial dilutions of Bacillus anthracis spores using quantitative real-time PCR (qPCR). The three kits determined by qPCR to yield the most sensitive and consistent detection (Epicenter MasterPure Gram Positive; MoBio PowerFood; ABI PrepSeq) were subsequently tested for their ability to isolate DNA from trace amounts of B. anthracis spores (approx. 6·5 × 10(1) and 1·3 × 10(2)  CFU in 25 ml or 50 g of food sample) spiked into complex food samples including apple juice, ham, whole milk and bagged salad and recovered with immunomagnetic separation (IMS). METHODS AND RESULTS: The MasterPure kit effectively and consistently isolated DNA from low amounts of B. anthracis spores captured from food samples. Detection was achieved from apple juice, ham, whole milk and bagged salad from as few as 65 ± 14, 68 ± 8, 66 ± 4 and 52 ± 16 CFU, respectively, and IMS samples were demonstrated to be free of PCR inhibitors. CONCLUSIONS: Detection of B. anthracis spores isolated from food by IMS differs substantially between commercial DNA extraction kits; however, sensitive results can be obtained with the MasterPure Gram Positive kit. SIGNIFICANCE AND IMPACT OF THE STUDY: The extraction protocol identified herein combined with IMS is novel for B. anthracis and allows detection of low levels of B. anthracis spores from contaminated food samples.


Assuntos
Bacillus anthracis/genética , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/análise , Microbiologia de Alimentos , Separação Imunomagnética , Reação em Cadeia da Polimerase em Tempo Real , Esporos Bacterianos/genética
17.
Diabetologia ; 55(5): 1505-13, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22322918

RESUMO

AIMS/HYPOTHESIS: Hyperfiltration is widely regarded as a contributing factor to the development of microalbuminuria and progressive nephropathy in type 1 diabetes. However, recent studies have questioned this conclusion. METHODS: To address this conflicting evidence, we examined the association between hyperfiltration and progression to microalbuminuria in 2,318 adults with type 1 diabetes. We also compared the estimated GFR in our diabetic patients with rates observed in 6,247 adults from the Finnish general population, using age- and sex-specific z scores. RESULTS: The distribution of estimated GFR in adults with type 1 diabetes and normoalbuminuria was not significantly different from that expected in the general population (p = 0.51, Mann-Whitney test). Type 1 diabetic patients with a higher estimated GFR were also no more likely to develop microalbuminuria over a median of 5.2 years of follow-up than those with normal estimated GFR. This was the case regardless of whether hyperfiltration was defined by an absolute threshold, deciles of estimated GFR or a z score, using creatinine- or cystatin-based clearance formulas in men or in women. CONCLUSIONS/INTERPRETATION: Together with other studies, these data suggest that creatinine- or cystatin-based estimates of GFR do not predict the development of microalbuminuria in patients with type 1 diabetes. Moreover, in the absence of incipient or overt nephropathy, conventionally determined renal function in patients with type 1 diabetes appears no different from that in the general population. This is hardly surprising, given that these individuals, by all definitions, do not have kidney disease.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Adolescente , Adulto , Albuminúria/epidemiologia , Albuminúria/etiologia , Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/epidemiologia , Progressão da Doença , Feminino , Finlândia/epidemiologia , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
18.
Clin Dev Immunol ; 2012: 652130, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22844324

RESUMO

The role of different receptors in natural-killer- (NK-) cell-mediated cytotoxicity against multiple myeloma (MM) cells is unknown. We investigated if an enhancement of NK-cell-mediated cytotoxicity against MM could be reached by blocking of the inhibitory leukocyte immunoglobulin-like receptor 1 (LIR-1). Our investigations revealed high levels of LIR-1 expression not only on the NK cell line NK-92, but also on myeloma cells (MOLP-8, RPMI8226) as well as on a lymphoblastoid cell line (LBCL; IM-9). Subsequent cytotoxicity assays were designed to show the isolated effects of LIR-1 blocking on either the effector or the tumor side to rule out receptor-receptor interactions. Although NK-92 was shown to be capable of myeloma cell lysis, inhibition of LIR-1 on NK-92 did not enhance cytotoxicity. Targeting the receptor on MM and LBCL did not also alter NK-92-mediated lysis. We come to the conclusion that LIR-1 alone does not directly influence NK-cell-mediated cytotoxicity against myeloma. To our knowledge, this work provides the first investigation of the inhibitory capability of LIR-1 in NK-92-mediated cytotoxicity against MM and the first functional evaluation of LIR-1 on MM and LBCL.


Assuntos
Antígenos CD/imunologia , Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Mieloma Múltiplo/imunologia , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/imunologia , Animais , Anticorpos Bloqueadores/imunologia , Anticorpos Monoclonais/imunologia , Células COS , Linhagem Celular , Chlorocebus aethiops , Humanos , Células Matadoras Naturais/metabolismo , Receptor B1 de Leucócitos Semelhante a Imunoglobulina
19.
Metabolism ; 128: 154961, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34958818

RESUMO

Type 2 diabetes is associated with an increased risk of cardiovascular disease, heart failure, chronic kidney disease, fatty liver disease, eye and foot disease. But equally, these conditions are associated with an increased risk of type 2 diabetes. Rather than being simply considered complications of diabetes, as exists within a 'pure' type 1 diabetes paradigm, both type 2 diabetes and its comorbidities are primarily caused by a failure to efficiently sequester excess energy leading to the accumulation of sick fat (adiposopathy). Type 2 diabetes is a symptom of a chronic disease complex, just as cardiovascular, renal, eye, foot and/or liver disease, are. In addition, each of these conditions feed forward so that dysfunction in one system accelerates dysfunction in another, partly through their shared pathogenesis and partly due dysfunction that follows in their wake. This review will explore the sticky, brittle conglomeration of CArdiac, Renal, Adipo-Metabolic, Eye and Liver disease (hereafter collectively known as CARAMEL disease) that is coincident in most patients with type 2 diabetes and contextualise the recent changes in diabetes guidelines that now specifically focus on identifying and aggressively managing these high-risk individuals with it.


Assuntos
Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/etiologia , Oftalmopatias/etiologia , Fígado Gorduroso/etiologia , Insuficiência Renal Crônica/etiologia , Comorbidade , Humanos
20.
Diabetologia ; 54(10): 2669-77, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21607631

RESUMO

AIMS/HYPOTHESIS: Activation of the receptor for AGE (RAGE) is implicated in the development and progression of vascular complications of diabetes. In this study, we explore factors and mortality outcomes associated with soluble RAGE (sRAGE) in a multicentre nationwide cohort of Finnish adults with type 1 diabetes. METHODS: Baseline sRAGE concentrations were estimated in 3,100 adults with type 1 diabetes. Clinical and biological variables independently associated with sRAGE were identified using multivariate regression analysis. Independent predictors of mortality were determined using Cox and Fine-Gray proportional-hazards models. RESULTS: The main independent determinants of sRAGE concentrations were estimated glomerular filtration rate, albuminuria, body mass index, age, duration of diabetes, HbA(1c) and insulin dose (all p < 0.05). During a median of 9.1 years of follow-up there were 202 deaths (7.4 per 1,000 patient years). sRAGE was independently associated with all-cause (Cox model: HR 1.03) and cardiovascular mortality (Fine-Gray competing risks model: HR 1.06) such that patients with the highest sRAGE concentrations had the greatest risk of mortality, after adjusting for age, sex, macrovascular disease, HDL-cholesterol, HbA(1c), triacylglycerol, high-sensitivity C-reactive protein (hsCRP) and the presence and severity of chronic kidney disease. Although polymorphisms in the gene coding for RAGE were significantly associated with sRAGE concentrations, none were associated with mortality outcomes. CONCLUSIONS/INTERPRETATION: Increased concentrations of sRAGE are associated with increased all-cause and cardiovascular mortality in type 1 diabetes, potentially reflecting the activation and production of RAGE in the context of accelerated vascular disease. These novel findings highlight the importance of the RAGE activation in the prevention and management of diabetic complications.


Assuntos
Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/mortalidade , Receptores Imunológicos/metabolismo , Adulto , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Feminino , Genótipo , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Polimorfismo Genético/genética , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/genética
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