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1.
Sci Total Environ ; 921: 171036, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38373449

RESUMO

findings are presented from an investigation to improve understanding of the environmental risks associated with developing an unconventional-hydrocarbons industry in the UK. The EQUIPT4RISK project, funded by UK Research Councils, focused on investigations around Preston New Road (PNR), Fylde, Lancashire, and Kirby Misperton Site A (KMA), North Yorkshire, where operator licences to explore for shale gas by hydraulic fracturing (HF) were issued in 2016, although exploration only took place at PNR. EQUIPT4RISK considered atmospheric (greenhouse gases, air quality), water (groundwater quality) and solid-earth (seismicity) compartments to characterise and model local conditions and environmental responses to HF activities. Risk assessment was based on the source-pathway-receptor approach. Baseline monitoring of air around the two sites characterised the variability with meteorological conditions, and isotopic signatures were able to discriminate biogenic methane (cattle) from thermogenic (natural-gas) sources. Monitoring of a post-HF nitrogen-lift (well-cleaning) operation at PNR detected the release of atmospheric emissions of methane (4.2 ± 1.4 t CH4). Groundwater monitoring around KMA identified high baseline methane concentrations and detected ethane and propane at some locations. Dissolved methane was inferred from stable-isotopic evidence as overwhelmingly of biogenic origin. Groundwater-quality monitoring around PNR found no evidence of HF-induced impacts. Two approaches for modelling induced seismicity and associated seismic risk were developed using observations of seismicity and operational parameters from PNR in 2018 and 2019. Novel methodologies developed for monitoring include use of machine learning to identify fugitive atmospheric methane, Bayesian statistics to assess changes to groundwater quality, a seismicity forecasting model seeded by the HF-fluid injection rate and high-resolution monitoring of soil-gas methane. The project developed a risk-assessment framework, aligned with ISO 31000 risk-management principles, to assess the theoretical combined and cumulative environmental risks from operations over time. This demonstrated the spatial and temporal evolution of risk profiles: seismic and atmospheric impacts from the shale-gas operations are modelled to be localised and short-lived, while risk to groundwater quality is longer-term.

3.
Nat Commun ; 10(1): 5028, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690720

RESUMO

Southern Africa is characterised by unusually elevated topography and abnormal heat flow. This can be explained by thermal perturbation of the mantle, but the origin of this is unclear. Geophysics has not detected a thermal anomaly in the upper mantle and there is no geochemical evidence of an asthenosphere mantle contribution to the Cenozoic volcanic record of the region. Here we show that natural CO2 seeps along the Ntlakwe-Bongwan fault within KwaZulu-Natal, South Africa, have C-He isotope systematics that support an origin from degassing mantle melts. Neon isotopes indicate that the melts originate from a deep mantle source that is similar to the mantle plume beneath Réunion, rather than the convecting upper mantle or sub-continental lithosphere. This confirms the existence of the Quathlamba mantle plume and importantly provides the first evidence in support of upwelling deep mantle beneath Southern Africa, helping to explain the regions elevation and abnormal heat flow.

4.
Mucosal Immunol ; 11(1): 50-60, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28513593

RESUMO

Loss-of-function mutations in the tyrosine kinase JAK3 cause autosomal recessive severe combined immunodeficiency (SCID). Defects in this form of SCID are restricted to the immune system, which led to the development of immunosuppressive JAK inhibitors. We find that the B6.Cg-Nr1d1tm1Ven/LazJ mouse line purchased from Jackson Laboratories harbors a spontaneous mutation in Jak3, generating a SCID phenotype and an inability to generate antigen-independent professional cytokine-producing innate lymphoid cells (ILCs). Mechanistically, Jak3 deficiency blocks ILC differentiation in the bone marrow at the ILC precursor and the pre-NK cell progenitor. We further demonstrate that the pan-JAK inhibitor tofacitinib and the specific JAK3 inhibitor PF-06651600 impair the ability of human intraepithelial ILC1 (iILC1) to produce IFN-γ, without affecting ILC3 production of IL-22. Both inhibitors impaired the proliferation of iILC1 and ILC3 and differentiation of human ILC in vitro. Tofacitinib is currently approved for the treatment of moderate-to-severely active rheumatoid arthritis. Both tofacitinib and PF-06651600 are currently in clinical trials for several other immune-mediated conditions. Our data suggest that therapeutic inhibition of JAK may also impact ILCs and, to some extent, underlie clinical efficacy.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Células da Medula Óssea/fisiologia , Janus Quinase 3/genética , Células Matadoras Naturais/fisiologia , Mutação/genética , Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Imunodeficiência Combinada Severa/genética , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Células Cultivadas , Humanos , Imunidade Inata , Interferon gama/metabolismo , Janus Quinase 3/antagonistas & inibidores , Camundongos , Camundongos Mutantes , Fenótipo , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia
5.
Mucosal Immunol ; 10(4): 936-945, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27827374

RESUMO

Plasmacytoid dendritic cells (pDCs) detect viruses initiating antiviral type I interferon responses. The microbiota is known to shape immune responses, but whether it influences pDC homeostasis and/or function is poorly understood. By comparing pDCs in germ-free and specific pathogen-free mice, we found that the microbiota supports homeostatic trafficking by eliciting constitutive levels of the chemokine CCL2 that engages CCR2. Mononuclear phagocytes were required for tonic CCL2 levels. CCL2 was particularly important for trafficking of a CCR2hi subset of pDCs that produced proinflammatory cytokines and was prone to apoptosis. We further demonstrated that CCR2 was also essential for pDC migration during inflammation. Wild-type (WT):Ccr2-/- mixed bone marrow chimeras revealed that CCR2 promotes pDC migration in a cell-intrinsic manner. Overall, we identify a novel role for the microbiota in shaping immunity, which includes induction of CCL2 levels that control homeostatic trafficking of pDCs.


Assuntos
Movimento Celular , Quimiocina CCL2/metabolismo , Células Dendríticas/imunologia , Inflamação/imunologia , Microbiota/imunologia , Animais , Apoptose , Células Cultivadas , Citocinas/metabolismo , Homeostase , Inflamação/microbiologia , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sistema Fagocitário Mononuclear , Receptores CCR2/genética , Receptores CCR2/metabolismo , Organismos Livres de Patógenos Específicos
7.
Oncogene ; 27(34): 4644-56, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18408764

RESUMO

The c-Myb oncoprotein is a DNA-binding transcription factor with a key role in early stages of hematopoiesis. To expand our knowledge of partners cooperating with c-Myb, we performed a yeast two-hybrid screening with full-length c-Myb as bait. Here, we report FLICE-associated huge protein (FLASH)/CASP8AP2 as a novel Myb-interacting protein. We show that FLASH interacts with the DNA-binding domain of c-Myb and enhances c-Myb-dependent reporter activity and expression of endogenous c-Myb target genes. Chromatin immunoprecipitation assays revealed that FLASH and c-Myb both associate with the MYC promoter region as well as with the intronic enhancer of the c-Myb target gene ADA. Furthermore, siRNA knock-down of FLASH or c-Myb both result in a reduction of MYC and ADA expression. The co-activator effect is mediated through the C-terminal part of FLASH, which binds c-Myb. The FLASH-induced enhancement is comparable with the increase seen with the c-Myb co-activator p300. We find FLASH localized in discrete nuclear speckles in several cell lines, co-localized with c-Myb in active RNA polymerase II foci. These results imply a novel molecular mechanism of regulation of c-Myb activity. We propose that c-Myb cooperates with FLASH in foci associated with active RNA polymerase II, leading to enhancement of Myb-dependent gene activation.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/fisiologia , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/fisiologia , Proteínas Proto-Oncogênicas c-myb/metabolismo , RNA Polimerase II/metabolismo , Animais , Proteínas Reguladoras de Apoptose/química , Células COS , Proteínas de Ligação ao Cálcio/química , Núcleo Celular/metabolismo , Células Cultivadas , Chlorocebus aethiops , Humanos , Células K562 , Camundongos , Células NIH 3T3 , Ligação Proteica , Estrutura Terciária de Proteína/fisiologia , Proteínas Proto-Oncogênicas c-myb/química , Proteínas Proto-Oncogênicas c-myb/fisiologia , Distribuição Tecidual , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Ativação Transcricional/fisiologia
9.
Eur J Clin Invest ; 32(8): 603-12, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12190960

RESUMO

BACKGROUND: HFE knockout mice (C57BL/6 x 129/Ola strain) mimic the functional aberrations of human hereditary haemochromatosis (HH) in short-term experiments. The present study investigates functional and morphological long-term changes. METHODS: HFE(o/o), HFE(+/o) and HFE(+/+) mice were maintained on iron-rich and control diets for 2 weeks, 3, 12 and 18 months. Light microscopic tissue iron distribution, pathomorphological alterations, tissue iron content and oxidative stress were analysed in liver, pancreas, spleen, gastrointestinal tract, kidneys and myocardium. Additionally, duodenal 59Fe absorption and 59Fe whole body loss were measured. RESULTS: Iron distribution between organs and microscopic iron deposition in the tissues resembled the patterns described in HH. After 3 months of iron-rich feeding duodenal 59Fe absorption decreased to approximately 15% of iron-adequate controls but remained about twice as high in HFE(o/o) as in HFE(+/+) mice. Hepatic iron concentrations reached only half the values known to induce hepatic fibrosis in rats and humans, while whole body 59Fe loss was about twice as high. Consequently no hepatic fibrosis developed, although massive hepatocellular iron deposition and indication for oxidative stress were observed. CONCLUSION: C57BL/6 x 129/O1a HFE(o/o) mice mimic HH iron distribution and the regulation of intestinal iron absorption after long-term feeding. However, characteristic morphological late changes in untreated HH are not modelled.


Assuntos
Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Ferro da Dieta/metabolismo , Proteínas de Membrana/genética , Modelos Animais , Animais , Duodeno/metabolismo , Hemocromatose/metabolismo , Proteína da Hemocromatose , Absorção Intestinal , Radioisótopos de Ferro , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Fatores de Tempo , Distribuição Tecidual
10.
J Exp Med ; 193(1): 89-99, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11136823

RESUMO

During variable/diversity/joining (V[D]J) recombination, the enzyme terminal deoxynucleotidyl transferase (Tdt) adds random nucleotides at the junctions of the rearranging gene segments, increasing diversity of the antibody (Ab) and T cell receptor repertoires. Two splice variants of Tdt have been described, but only one (short isoform of Tdt [TdtS]) has been convincingly demonstrated to catalyze nontemplated (N) addition in vitro. We have expressed each splice variant of Tdt in transgenic (Tg) mice and found that the TdtS transgene catalyzes N addition on the endogenous Tdt(-/)- background and in fetal liver, but that the long isoform of Tdt (TdtL) transgene does neither. In contrast to previous in vitro results, both TdtS and TdtL are translocated to the nucleus in our model. Furthermore, TdtL/TdtS double Tg mice exhibit less N addition in fetal liver than do TdtS Tg mice. Whereas the TdtS transgene was shown to have functional consequences on the antiphosphorylcholine (PC) B cell repertoire, TdtL Tg mice exhibit a normal PC response, and Tdt(-/)- mice actually exhibit an increase in the PC response and in TEPC 15 idiotype(+) Ab production. We conclude that TdtL localizes to the nucleus in vivo where it serves to modulate TdtS function.


Assuntos
DNA Nucleotidilexotransferase/metabolismo , Processamento Alternativo , Animais , Sequência de Bases , Catálise , Núcleo Celular/enzimologia , Clonagem Molecular , DNA Nucleotidilexotransferase/genética , Primers do DNA/genética , DNA Complementar/genética , Feto/imunologia , Feto/metabolismo , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Isoenzimas/genética , Isoenzimas/metabolismo , Fígado/enzimologia , Fígado/imunologia , Linfócitos/enzimologia , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nucleotídeos/metabolismo
11.
Health Serv Res ; 35(3): 735-54, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10966093

RESUMO

OBJECTIVE: To compare three methods for rating legitimate use of psychiatric emergency services (PES) in order to develop criteria that can differentiate appropriate from inappropriate PES service requests. METHOD: Ratings of PES visits by treating physicians and ratings of the same visits made during review of medical records. STUDY DESIGN: Two previously used methods of identifying justified PES service use were compared with the treating physician's rating of the same: (1) hospitalization as visit outcome and (2) retrospective chart ratings of visit characteristics using traditional medico-surgical criteria for "emergent" illness episodes. DATA EXTRACTION METHODS: Data were extracted through use of a physician questionnaire, and medical and administrative record review. PRINCIPAL FINDINGS: Agreement between the methods ranged from 47.1 percent to 74.1 percent. A total of 21.7 percent of visits were rated as true health "emergencies" by the traditional definition, while 70.4 percent of visits were rated as "necessary" by treating physicians, and 21.0 percent resulted in hospitalization. Acuteness of behavioral dyscontrol and imminent dangerousness at the time of the visit were common characteristics of appropriate use by most combinations of the three methods of rating visits. CONCLUSIONS: The rating systems employed in similar recent studies produce widely varying percentages of visits so classified. However, it does appear likely that a minimum of 25-30 percent of visits are nonemergent and could be triaged to other, less costly treatment providers. Proposed criteria by which to identify "legitimate" psychiatric emergency room treatment requests includes only patient presentations with (a) acute behavioral dyscontrol or (b) imminent dangerousness to self or others.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Serviços de Emergência Psiquiátrica/estatística & dados numéricos , Transtornos Mentais/classificação , Avaliação das Necessidades , Revisão da Utilização de Recursos de Saúde , Adolescente , Adulto , Feminino , Pesquisa sobre Serviços de Saúde , Hospitais Municipais/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Auditoria Médica , Texas/epidemiologia
12.
Immunol Rev ; 175: 150-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10933600

RESUMO

In mice, the absence of terminal deoxynucleotidyl transferase (Tdt) expression during fetal and neonatal life provides a window in development where clones of lymphocytes are generated that provide protective immunity. Introducing premature Tdt activity interferes with the development of these clones and results in an impaired ability to make protective antibodies. Conversely, gene-targeted disruption of Tdt prevents N additions at all stages of T and B-lymphocyte development and promotes the development of fetal-like T and B-cell clones into adulthood, with accompanying alterations in repertoire. The alternative splice forms of Tdt may be necessary to provide regulatory mechanisms to restrict N addition to appropriate stages of the developmental pathways, the details of which are being revealed. The evidence continues to build that Tdt is a key player in influencing the outcome of V(D)J recombination during lymphocyte and repertoire development.


Assuntos
Linfócitos B/imunologia , DNA Nucleotidilexotransferase/fisiologia , Rearranjo Gênico do Linfócito B , Animais , Linfócitos B/enzimologia , Células da Medula Óssea/imunologia , Linhagem da Célula , Núcleo Celular/metabolismo , DNA Nucleotidilexotransferase/genética , Desenvolvimento Embrionário e Fetal , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Idiótipos de Imunoglobulinas , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/metabolismo , Fígado/embriologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Nucleotídeos/metabolismo , Fosforilcolina/imunologia , Isoformas de Proteínas , Linfócitos T/imunologia , Transgenes
13.
Psychiatr Serv ; 51(7): 924-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10875960

RESUMO

Utilization rates for urban psychiatric emergency services remain high, and the decision to seek care in this setting is poorly understood. Three hundred individuals accompanying patients to a psychiatric emergency service were interviewed about their help seeking and choice of treatment setting. Twenty-three of the interviewees (7.7 percent) were caregivers accompanying patients with severe and persistent mental illness. They were significantly more likely than other interviewees to know the difference between psychiatric emergency services and services offered by other outpatient providers. More than half reported that the patient they accompanied was intermittently noncompliant, which required visiting either a walk-in service during a moment when the patient was cooperative or a facility equipped to provide involuntary treatment.


Assuntos
Cuidadores/estatística & dados numéricos , Tomada de Decisões , Serviços de Emergência Psiquiátrica/estatística & dados numéricos , Comportamentos Relacionados com a Saúde , Transtornos Mentais , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
14.
Proc Natl Acad Sci U S A ; 96(23): 13312-7, 1999 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-10557317

RESUMO

The puzzling linkage between genetic hemochromatosis and histocompatibility loci became even more so when the gene involved, HFE, was identified. Indeed, within the well defined, mainly peptide-binding, MHC class I family of molecules, HFE seems to perform an unusual yet essential function. As yet, our understanding of HFE function in iron homeostasis is only partial; an even more open question is its possible role in the immune system. To advance on both of these avenues, we report the deletion of HFE alpha1 and alpha2 putative ligand binding domains in vivo. HFE-deficient animals were analyzed for a comprehensive set of metabolic and immune parameters. Faithfully mimicking human hemochromatosis, mice homozygous for this deletion develop iron overload, characterized by a higher plasma iron content and a raised transferrin saturation as well as an elevated hepatic iron load. The primary defect could, indeed, be traced to an augmented duodenal iron absorption. In parallel, measurement of the gut mucosal iron content as well as iron regulatory proteins allows a more informed evaluation of various hypotheses regarding the precise role of HFE in iron homeostasis. Finally, an extensive phenotyping of primary and secondary lymphoid organs including the gut provides no compelling evidence for an obvious immune-linked function for HFE.


Assuntos
Genes MHC Classe I/imunologia , Antígenos HLA/imunologia , Hemocromatose/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Ferro/metabolismo , Proteínas de Membrana , Animais , Sequência de Bases , Primers do DNA , Proteína da Hemocromatose , Humanos , Camundongos , Camundongos Mutantes , Mutação , Fenótipo
15.
J Immunol ; 162(6): 3471-80, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10092803

RESUMO

Temporal control of rearrangement at the TCR alpha/delta locus is crucial for development of the gamma delta and alpha beta T cell lineages. Because the TCR delta locus is embedded within the alpha locus, rearrangement of any V alpha-J alpha excises the delta locus, precluding expression of a functional gamma delta TCR. Approximately 100 kb spanning the C delta-C alpha region has been sequenced from both human and mouse, and comparison has revealed an unexpectedly high degree of conservation between the two. Of interest in terms of regulation, several highly conserved sequence blocks (> 90% over > 50 bp) were identified that did not correspond to known regulatory elements such as the TCR alpha and delta enhancers or to coding regions. One of these blocks lying between J alpha 4 and J alpha 3, which appears to be conserved in other vertebrates, has been shown to augment TCR alpha enhancer function in vitro and differentially bind factors from nuclear extracts. To further assess a plausible regulatory role for this element, we have created mice in which this conserved sequence block is either deleted or replaced with a neomycin resistance gene driven by the phosphoglycerate kinase promoter (pgk-neor). Deletion of this conserved sequence block in vivo did have a local effect on J alpha usage, echoing the in vitro data. However, its replacement with pgk-neor had a much more dramatic, long range effect, perhaps underscoring the importance of maintaining overall structure at this locus.


Assuntos
Sequência Conservada/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Animais , Sequência de Bases , Sequência Conservada/genética , Cruzamentos Genéticos , Resistência a Medicamentos/genética , Regulação da Expressão Gênica/imunologia , Rearranjo Gênico da Cadeia alfa dos Receptores de Antígenos dos Linfócitos T , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Transgênicos , Dados de Sequência Molecular , Neomicina , Fosfoglicerato Quinase/genética , Receptores de Antígenos de Linfócitos T alfa-beta/biossíntese , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Deleção de Sequência
17.
J Immunol ; 161(12): 6629-37, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9862691

RESUMO

Interactions of the T cell coreceptors, CD4 and CD8, with MHC molecules participate in regulating thymocyte development and T lymphocyte activation and differentiation to memory T cells. However, the exact roles of these interactions in normal T cell development and function remain unclear. CD4 interacts with class II MHC7 molecules via several noncontiguous regions in both the class II MHC alpha- and beta-chains. We have introduced a double mutation that disrupts interaction with CD4 into the I-A(beta)k gene and used this construct to generate transgenic mice expressing only mutant class II MHC. Although CD4+ thymocytes matured to the single-positive stage in these mice, their frequency was reduced by threefold compared with that of wild-type transgenics. Positive selection of CD4+ T cells in the mutant transgenic mice may have been mediated by TCRs with a higher than usual affinity for class II MHC/Ag complexes. In A(beta)k mutant transgenics, peripheral CD4+ lymphocytes promoted B cell differentiation to plasma cells. These CD4+ T cells also secreted IFN-gamma in response to various stimuli (e.g., protein Ag, bacterial superantigen, and alloantigen), but were deficient in IL-2 secretion. Interactions between CD4 and class II MHC molecules appeared to regulate lymphokine production, with a strong bias toward IFN-gamma and against IL-2 in the absence of these interactions. Our results have implications for the manipulation of T cell-dependent immune responses.


Assuntos
Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/imunologia , Deleção Clonal , Antígenos de Histocompatibilidade Classe II/metabolismo , Substituição de Aminoácidos , Animais , Formação de Anticorpos , Antígenos de Bactérias/imunologia , Sítios de Ligação , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Diferenciação Celular , Células Cultivadas , Enterotoxinas/imunologia , Hemocianinas/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Imunização , Memória Imunológica , Linfonodos/citologia , Camundongos , Camundongos Transgênicos , Mutagênese , Baço/citologia , Relação Estrutura-Atividade , Superantígenos/imunologia
18.
J Immunol ; 161(12): 7023-30, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9862739

RESUMO

Terminal deoxynucleotidyl transferase (TdT) enzyme activity in lymphocytes generates diversity in the Ag receptor repertoires by adding template-independent N nucleotides and disrupting homology-directed rearrangements. The importance of this diversity in vivo and the significance of the suppression of TdT during fetal life remain uncertain. Previous studies have shown that in TdT knockout mice (TdT(0)) 1) the T cell repertoire is less peptide oriented; and 2) natural autoantibody, particularly anti-DNA autoantibodies, are less polyreactive, and their mean affinities are reduced. Consequently, the suppression of TdT during early T/B cell ontogeny may participate in controlling autoimmunity. To study the impact of TdT suppression in autoimmune-prone mice, we introduced the TdT null mutation into the (NZB x NZW)F1 (B/W) mouse strain. We show that TdT deficiency significantly reduces the incidence of autoimmune nephritis and prolongs survival compared with those in control mice. Surprisingly, the long-term survivor TdT(0) mice produced amounts of anti-ADN and anti-histone autoantibodies similar to those of their TdT+ littermates. However, these TdT(0) mice showed no evidence of renal inflammation, and the immune deposits were restricted to the mesangium, whereas basal membrane deposits were clearly correlated with overt renal disease. The present study supports the idea that the absence of TdT enzyme activity in lymphocytes protects mice against autoimmunity and could offer a therapeutic approach to autoimmune diseases. Moreover, our results may help to unravel the mechanisms of lupus nephritis.


Assuntos
Doenças Autoimunes/genética , Linfócitos B/imunologia , DNA Nucleotidilexotransferase/fisiologia , Rearranjo Gênico do Linfócito B , Rearranjo Gênico do Linfócito T , Nefrite Lúpica/genética , Linfócitos T/imunologia , Animais , Autoanticorpos/sangue , Doenças Autoimunes/enzimologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Doenças Autoimunes/prevenção & controle , Linfócitos B/patologia , Cruzamentos Genéticos , DNA Nucleotidilexotransferase/deficiência , DNA Nucleotidilexotransferase/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Mesângio Glomerular/patologia , Hipergamaglobulinemia/genética , Nefrite Lúpica/enzimologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Nefrite Lúpica/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos NZB , Camundongos Endogâmicos , Camundongos Knockout , Repetições de Microssatélites , Proteinúria/etiologia , Proteinúria/prevenção & controle
19.
Psychiatr Serv ; 49(6): 825-8, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9634166

RESUMO

Current illicit drug and alcohol users were identified by laboratory evaluation of urine samples from nonpsychotic patients without a primary clinical diagnosis of a substance use disorder seen in a psychiatric emergency room. Urine screens revealed that 32 of 93 nonpsychotic patients (34 percent) had used a substance just before visiting the emergency room. Compared with nonusers, users were more often Caucasian females with adjustment disorders who admitted their previous substance use. The prevalence of concurrent use among nonpsychotic patients was higher than among psychotic patients. Nonpsychotic and psychotic users differed in gender, marital status, level of suicidality, self-report of use, the clinician's suspicion of use, use of seclusion during the visit, admitting status, level of care, and disposition.


Assuntos
Alcoolismo/epidemiologia , Serviços de Emergência Psiquiátrica/estatística & dados numéricos , Drogas Ilícitas , Transtornos Psicóticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos de Adaptação/diagnóstico , Transtornos de Adaptação/epidemiologia , Adolescente , Adulto , Alcoolismo/diagnóstico , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/estatística & dados numéricos , Transtornos Psicóticos/diagnóstico , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Texas/epidemiologia
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