RESUMO
BACKGROUND: The COVID-19 pandemic has placed significant pressure on health and social care. Survivors of COVID-19 may be left with substantial functional deficits requiring ongoing care. We aimed to determine whether pre-admission frailty was associated with increased care needs at discharge for patients admitted to hospital with COVID-19. METHODS: Patients were included if aged over 18 years old and admitted to hospital with COVID-19 between 27 February and 10 June 2020. The Clinical Frailty Scale (CFS) was used to assess pre-admission frailty status. Admission and discharge care levels were recorded. Data were analysed using a mixed-effects logistic regression adjusted for age, sex, smoking status, comorbidities, and admission CRP as a marker of severity of disease. RESULTS: Thirteen hospitals included patients: 1671 patients were screened, and 840 were excluded including, 521 patients who died before discharge (31.1%). Of the 831 patients who were discharged, the median age was 71 years (IQR, 58-81 years) and 369 (44.4%) were women. The median length of hospital stay was 12 days (IQR 6-24). Using the CFS, 438 (47.0%) were living with frailty (≥ CFS 5), and 193 (23.2%) required an increase in the level of care provided. Multivariable analysis showed that frailty was associated with an increase in care needs compared to patients without frailty (CFS 1-3). The adjusted odds ratios (aOR) were as follows: CFS 4, 1.99 (0.97-4.11); CFS 5, 3.77 (1.94-7.32); CFS 6, 4.04 (2.09-7.82); CFS 7, 2.16 (1.12-4.20); and CFS 8, 3.19 (1.06-9.56). CONCLUSIONS: Around a quarter of patients admitted with COVID-19 had increased care needs at discharge. Pre-admission frailty was strongly associated with the need for an increased level of care at discharge. Our results have implications for service planning and public health policy as well as a person's functional outcome, suggesting that frailty screening should be utilised for predictive modelling and early individualised discharge planning.
Assuntos
Assistência ao Convalescente/estatística & dados numéricos , COVID-19 , Fragilidade/complicações , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , COVID-19/reabilitação , Estudos de Coortes , Comorbidade , Feminino , Fragilidade/reabilitação , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , SARS-CoV-2RESUMO
BACKGROUND: Hospital admissions for non-coronavirus disease 2019 (COVID-19) pathology have decreased significantly. It is believed that this may be due to public anxiety about acquiring COVID-19 infection in hospital and the subsequent risk of mortality. AIM: To identify patients who acquire COVID-19 in hospital (nosocomial COVID-19 infection (NC)) and their risk of mortality compared to those with community-acquired COVID-19 (CAC) infection. METHODS: The COPE-Nosocomial Study was an observational cohort study. The primary outcome was the time to all-cause mortality (estimated with an adjusted hazard ratio (aHR)), and secondary outcomes were day 7 mortality and the time-to-discharge. A mixed-effects multivariable Cox's proportional hazards model was used, adjusted for demographics and comorbidities. FINDINGS: The study included 1564 patients from 10 hospital sites throughout the UK, and one in Italy, and collected outcomes on patients admitted up to April 28th, 2020. In all, 12.5% of COVID-19 infections were acquired in hospital; 425 (27.2%) patients with COVID died. The median survival time in NC patients was 14 days compared with 10 days in CAC patients. In the primary analysis, NC infection was associated with lower mortality rate (aHR: 0.71; 95% confidence interval (CI): 0.51-0.98). Secondary outcomes found no difference in day 7 mortality (adjusted odds ratio: 0.79; 95% CI: 0.47-1.31), but NC patients required longer time in hospital during convalescence (aHR: 0.49, 95% CI: 0.37-0.66). CONCLUSION: The minority of COVID-19 cases were the result of NC transmission. No COVID-19 infection comes without risk, but patients with NC had a lower risk of mortality compared to CAC infection; however, caution should be taken when interpreting this finding.
Assuntos
Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/transmissão , Infecção Hospitalar/mortalidade , Infecção Hospitalar/transmissão , Idoso Fragilizado/estatística & dados numéricos , Mortalidade Hospitalar , Pneumonia Viral/mortalidade , Pneumonia Viral/transmissão , Medição de Risco/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/epidemiologia , Infecção Hospitalar/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Modelos de Riscos Proporcionais , Fatores de Risco , SARS-CoV-2 , Índice de Gravidade de DoençaRESUMO
Accurate and stable x-ray beam position monitors (XBPMs) are key elements in obtaining the desired user beam stability in the Advanced Photon Source Upgrade. In the next-generation XBPMs for the canted-undulator front ends, where two undulator beams are separated by 1.0 mrad, the lower beam power (<10 kW) per undulator allows us to explore lower-cost solutions based on Compton scattering from a diamond placed edge-on to the x-ray beam. Because of the high peak power density of the x-ray beams, this diamond experiences high temperatures and has to be clamped to a water-cooled heat spreader using thermal interface materials (TIMs), which play a key role in reducing the temperature of the diamond. To evaluate temperature changes through the interface via thermal simulations, the thermal contact resistance (TCR) of TIMs at an interface between two solid materials under even contact pressure must be known. This paper addresses the TCR measurements of several TIMs, including gold, silver, pyrolytic graphite sheet, and 3D graphene foam. In addition, a prototype of a Compton-scattering XBPM with diamond blades was installed at APS Beamline 24-ID-A in May 2015 and has been tested. This paper presents the design of the Compton-scattering XBPM, and compares thermal simulation results obtained for the diamond blade of this XBPM by the finite element method with in situ empirical measurements obtained by using reliable infrared technology.
RESUMO
BACKGROUND: Eosinophilic esophagitis (EE) is an emerging condition where patients commonly present with symptoms of gastroesophageal reflux disease and fail to respond adequately to anti-reflux therapy. Food allergy is currently recognized as the main immunological cause of EE; recent evidence suggests an etiological role for inhalant allergens. The presence of EE appears to be associated with other atopic illnesses. OBJECTIVES: To report the sensitization profile of both food and inhalant allergens in our EE patient cohort in relation to age, and to profile the prevalence of other allergic conditions in patients with EE. METHOD: The study prospectively analyzed allergen sensitization profiles using skin prick tests to common food allergens and inhalant allergens in 45 children with EE. Patch testing to common food allergens was performed on 33 patients in the same cohort. Comorbidity of atopic eczema, asthma, allergic rhinitis and anaphylaxis were obtained from patient history. RESULTS: Younger patients with EE showed more IgE and patch sensitization to foods while older patients showed greater IgE sensitization to inhalant allergens. The prevalence of atopic eczema, allergic rhinitis and asthma was significantly increased in our EE cohort compared with the general Australian population. A total of 24% of our cohort of patients with EE had a history of anaphylaxis. CONCLUSION: In children with EE, the sensitization to inhalant allergens increases with age, particularly after 4 years. Also, specific enquiry about severe food reactions in patients presenting with EE is strongly recommended as it appears this patient group has a high incidence of anaphylaxis.
Assuntos
Alérgenos/imunologia , Eosinofilia/imunologia , Esofagite/imunologia , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Imediata/imunologia , Adolescente , Austrália , Criança , Pré-Escolar , Estudos de Coortes , Comorbidade , Eosinófilos/imunologia , Esofagite/etiologia , Humanos , Lactente , Testes do Emplastro , Testes CutâneosRESUMO
The diagnosis of cystic adventitial degeneration (CAD) is difficult. We present the first case in which intravascular ultrasound (IVUS) correctly identified CAD of the popliteal artery when duplex sonography and angiography were inconclusive.
Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/diagnóstico , Cistos/diagnóstico por imagem , Artéria Poplítea/diagnóstico por imagem , Ultrassonografia de Intervenção , Adulto , Angiografia , Diagnóstico Diferencial , Humanos , Masculino , Ultrassonografia Doppler Dupla , Ultrassonografia de Intervenção/métodosRESUMO
Several results indicate that transcriptional enhancers lying 3' of the Calpha gene regulate RNA expression and switch recombination of heavy chain genes. To investigate this regulation we prepared transgenic mice with a 10.5-kb transgene that included the germline form of the murine gamma2alpha gene, including promoter, I, S, and C regions. RNA was expressed from these gamma2a transgenes with correct IFN-gamma regulation, in spite of the fact that they lacked the 3' enhancers. This RNA expression was independent of insertion site and dependent on copy number, indicating that the gamma2a gene includes locus control region-like elements. Addition of either a cassette containing 3' enhancer DNase I hypersensitive sites 1, 2, 3B, and 4 or the intronic micro enhancer increased transcription from the gamma2a transgene by approximately 75-fold in B cells. However, this increased transcription was not responsive to IFN-gamma treatment of the transgenic B cells.
Assuntos
Linfócitos B/imunologia , Elementos Facilitadores Genéticos , Células Germinativas/imunologia , Imunoglobulina G/biossíntese , Cadeias Pesadas de Imunoglobulinas/genética , Interferon gama/farmacologia , Animais , Dosagem de Genes , Regulação da Expressão Gênica , Switching de Imunoglobulina/genética , Camundongos , Camundongos Transgênicos , RNA Mensageiro/biossíntese , TransgenesRESUMO
BACKGROUND: Neutrophil infiltration is a characteristic feature of the hepatic injury associated with prolonged hypotension. Previous work has already stressed the important contribution of neutrophil-endothelial cell interactions in the organ injury seen after hemorrhagic shock. Single-blockade strategies using monoclonal antibodies (MAbs) against either selectin or integrin receptors have been demonstrated to be effective in limiting the tissue inflammatory response observed in this clinical disorder. One unexplored topic is the additive effect(s) and the potential antiinflammatory properties of the combined blocking of P-selectin plus beta2-integrin in the liver inflammatory response after uncontrolled hemorrhagic shock in rats. STUDY DESIGN: Sprague-Dawley rats (n = 64) weighing 250-300 g were included in a three-phase model of uncontrolled hemorrhagic shock. A prehospital phase consisted of 90 minutes of fluid resuscitation with lactated Ringer's solution to reach a mean arterial pressure (MAP) of 40 mmHg; a hospital phase consisted of 60 minutes of hemostasis and fluid resuscitation with lactated Ringer's solution to reach a MAP of 80 mmHg; and the third phase was 3 days of observation. All rats had 3 mL/100 g of blood volume shed during the initial 15 minutes. At 30 minutes, 75% tail amputation produced uncontrolled hemorrhagic shock. Four groups were randomized (n = 16 per group), and treatment at the beginning of resuscitation included normal saline (group 1); anti-P-selectin MAb, RMP-1 (group 2); anti-beta2-integrin MAb, WT.3 (group 3); or anti-P-selectin plus anti-beta2-integrin MAbs (group 4). The following indices were evaluated: fluid requirements for resuscitation, liver injury tests, liver tissue myeloperoxidase, and liver histology. RESULTS: Dual blockade of P-selectin and beta2-integrin significantly reduced fluid requirements for resuscitation (p < 0.05). We also observed a statistically significant improvement (p < 0.05) in tests demonstrating hepatic injury, myeloperoxidase in hepatic tissue, and histology studies. Survival was increased from 40% in controls to 60% with the dual-blockade treatment. CONCLUSIONS: These results indicate that dual-blockade strategies aimed at P-selectin and beta-integrin provided a protective effect in the liver inflammatory response after uncontrolled hemorrhagic shock in rats. Although dual blockade was more effective than either individual blockade alone, questions remain about the possible redundancy in the inflammatory adhesion pathways after this clinical condition.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD18/imunologia , Inflamação/prevenção & controle , Hepatopatias/prevenção & controle , Selectina-P/imunologia , Choque Hemorrágico/complicações , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Inflamação/etiologia , Inflamação/patologia , Hepatopatias/enzimologia , Hepatopatias/etiologia , Hepatopatias/patologia , Masculino , Peroxidase/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Little is known about the changes in the hepatic microcirculation and the leukocyte-endothelial adhesion processes during the early reperfusion period after resuscitation in hemorrhagic shock. P-selectin and its natural ligand Sialyl Lewis(x) (SLe(x)) are involved in the early stages of reperfusion events leading to neutrophil migration. Therefore, the aim of this study was to investigate the effect of the administration of CY-1503 [corrected], a synthetic SLe(x) analog, in the liver inflammatory response and neutrophil migration after hemorrhagic shock. MATERIALS AND METHODS: Rats, each weighing 275 to 300 grams, were subjected to 60 minutes of pressure controlled hemorrhagic shock. After this period, animals were resuscitated according to the following protocol: shed blood was reinfused to equal 50% of the total volume bled, and the other 50% was replaced with 3x volume of Ringer's lactated solution. Animals were divided into sham and two study groups to receive vehicle (controls) and CY-1503 [corrected] (10 mg/kg intravenously) diluted in 1 mL of normal saline 45 minutes after initiating hemorrhagic shock. The following parameters were analyzed: 7-day survival, liver injury tests, liver tissue myeloperoxidase as an index of neutrophil infiltration, and liver histology. RESULTS: Survival was significantly increased from 48% in the controls to 90% in the CY-1503 [corrected] treated group. Animals treated with the SLe(x) analog showed significantly better mean arterial blood pressure after 15 minutes after resuscitation. Also, the treated group showed a marked decrease in liver enzymes levels at 5 minutes and 4 hours after reperfusion. Neutrophil migration was significantly ameliorated as reflected by decreased myeloperoxidase levels in the SLe(x) analog treated group. Furthermore, we observed improved histologic damage scores in the treated group when compared with controls. CONCLUSIONS: The SLe(x) analog, CY-1503 [corrected], had a protective effect in ischemic livers by decreasing neutrophil migration after hemorrhagic shock and resuscitation. This protective effect also resulted in improved survival and mean arterial blood pressure after resuscitation.
Assuntos
Fígado/efeitos dos fármacos , Fígado/imunologia , Ativação de Neutrófilo/efeitos dos fármacos , Oligossacarídeos/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Choque Hemorrágico/imunologia , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Inflamação , Circulação Hepática/efeitos dos fármacos , Masculino , Selectina-P/imunologia , Ratos , Ratos Sprague-Dawley , Antígeno Sialil Lewis X , Análise de SobrevidaRESUMO
Interleukin-12 (IL-12) is a pivotal cytokine that has dramatic effects on cell-mediated immunity. It is now becoming increasingly recognized that IL-12 also strongly controls humoral immunity. We have investigated the mechanism by which IL-12 induces alterations in antibody isotype expression by determining the influence of IL-12 on in vitro immunoglobulin (Ig) production in polyclonally activated murine spleen cell cultures. Cells exposed to IL-12 plus lipopolysaccharide or anti-CD40 monoclonal antibody showed dramatically elevated IgG2a and suppressed IgG1 production compared to cells cultured in the absence of IL-12. IL-12 treatment of spleen cell cultures induced expression of gamma2a germ-line transcripts, consistent with initiation of switch recombination to IgG2a. In addition, exposure of limiting dilution cultures to IL-12 increased IgG2a+ cell precursor frequency. All of the above results were dependent on interferon-gamma (IFN-gamma). However, in the absence of IFN-gamma, IL-12 still had significant effects on Ig secretion. Specifically, IL-12 enhanced IgG1 and IgG2b anti-DNP antibody levels in mice containing specific disruptions in the IFN-gamma gene. Our results suggest that IL-12 induces T helper type 1 and natural killer cells to secrete large amounts of IFN-gamma which then causes B cells to switch to IgG2a and IgG3 production. In addition, IL-12 has direct or indirect effects on B cells that are independent of IFN-gamma. The IFN-gamma-independent effects may include enhancement of Ig expression by post-switched cells.
Assuntos
Adjuvantes Imunológicos/farmacologia , Formação de Anticorpos , Interferon gama/metabolismo , Interleucina-12/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD40/metabolismo , Células Cultivadas , Imunoglobulina G/biossíntese , Imunoglobulina G/genética , Interferon gama/genética , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Baço/citologia , Baço/imunologiaRESUMO
The cis-acting elements that regulate production of germ-line transcripts from Ig heavy chain genes and subsequent switch recombination to those genes are poorly defined. We reported that a 17-kb transgene that includes Igamma1, Sgamma1, and Cgamma1 is regulated for germ-line transcription like the endogenous gamma1 gene. Transcripts from such transgenes are expressed only in B cells treated with both LPS and IL-4, and not in B cells treated with LPS alone or in thymocytes or nonlymphoid tissues. We have now found that transcripts from these transgenes are induced by treatment of transgenic B cells by IL-4 alone. As reported by others, IFN-gamma acts to inhibit the IL-4-mediated induction of germ-line transcripts of the endogenous gamma1 gene. We have found that LPS-plus IL-4-induced germ-line transcription of gamma1 transgenes is likewise inhibited by treatment of B cells with IFN-gamma, so the gamma1 gene must include the cis-acting element(s) that confers this inhibition. It is also known that CD40 ligation induces a modest amount of germ-line transcripts from the endogenous gamma1 gene and synergizes with IL-4 to induce large amounts of germ-line transcripts. The gamma1 transgenes are likewise induced by CD40 ligation, suggesting that the response element(s) for CD40 ligation can be found in the gamma1 gene. The promoter region for the germ-line transcripts and the I exon are likely to include some of these cis-acting elements. A series of transgenic mice with the promoter/Igamma1 region conferred low level, lymphoid-specific, RNA expression to a reporter gene, including significant expression in thymocytes. However, the promoter/Igamma1 transgenes were not regulated like the endogenous gamma1 gene, in that transcription in splenic B cells was not increased by LPS plus IL-4.
Assuntos
Antígenos CD40/fisiologia , Genes de Imunoglobulinas , Imunoglobulina G/genética , Interferon gama/fisiologia , Regiões Promotoras Genéticas , Animais , Regulação da Expressão Gênica , Genes de Troca , Interleucina-4/fisiologia , Ligantes , Camundongos , Camundongos Transgênicos , RNA Mensageiro/genética , Recombinação Genética , Transcrição GênicaRESUMO
We have found that IL-12 treatment of mice leads to long-lasting enhancement in production of most antibody isotypes in conventional B-cell responses. Initial recruitment of new B-cell clones into the response is mediated by IFN-gamma, but subsequent enhancement of Ig secretion appears to be IFN-gamma-independent. We have further found that activated B cells can directly bind IL-12. Taken together, our results suggest a two-step model for the role of IL-12 in enhancement of humoral immunity. Initially, IL-12 induces production of IFN-gamma from Th1 and NK cells. Enough cytokine can be produced from either cell type to then mediate gamma 2a heavy chain isotype switching as well as temporary suppression of IgG1 production. IL-12 further stimulates post-switched cells, including cells producing IgG1, to secrete greatly increased amounts of antibody. This step is not mediated by IFN-gamma but might be due to direct IL-12 binding to activated B lymphocytes. Depletion of B1 cells by IL-12 may further enhance antibody responsiveness since B1 cells are known to competitively inhibit Ig secretion by conventional B cells. The end result is that IL-12 causes a generalized upregulation in production of all antibodies and therefore acts as a strong adjuvant for humoral as well as cellular immunity.
Assuntos
Formação de Anticorpos , Interleucina-12/fisiologia , Adjuvantes Imunológicos , Animais , Linfócitos B/imunologia , Genes de Imunoglobulinas , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Muramidase/imunologia , Fatores de TempoRESUMO
A series of 1,2-diarylcyclopentene methyl sulfones and sulfonamides have been shown to be remarkably potent and selective cyclooxygenase-2 (COX-2) inhibitors. The methyl sulfone analogs 7 showed excellent COX-2 activity, with IC50s ranging from 0.003 (7f,n) to 0.87 (7o) microM. In addition, most analogs of 7 showed no activity (IC50 > 100 microM) against the COX-1 enzyme. Replacement of the methyl sulfone moiety with a sulfonamide group gave a slightly more potent (typically 2-5-fold) but less selective COX-2 inhibitor, mainly due to an increase (20- > 100-fold) in COX-1 activity. However, in vitro COX-1/COX-2 selectivity for the sulfonamides 8 could be increased in many cases by simply incorporating a substituent at the 3-position of the phenyl group. Furthermore, in vitro selectivity increased with the size and number of substituents, as demonstrated in the selectivity trend of 8k (8000) > 8j (1900) > 8i (500) > 8h (100). More importantly, the sulfonamide COX-2 inhibitors showed greatly enhanced oral activity in the rat model of established adjuvant-induced arthritis, with inhibition values of 79.0% (8a), 81.5% (8c), and 83.0% (8g) at 1 mg/kg. On the basis of its overall biological profile, sulfonamide 8c was evaluated as a potential clinical candidate, displaying an ED50 of 22 mpk in the rat carrageenan-induced paw edema model and an ED50 of 0.16 mpk in the rat established adjuvant-induced arthritis model with no indication of gastrointestinal toxicity in rats and mice at 200 mpk. In addition, a preparative-scale synthetic route to sulfonamide 8c has been developed.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Ciclopentanos/farmacologia , Sulfonamidas/farmacologia , Sulfonas/farmacologia , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/síntese química , Artrite Experimental/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/síntese química , Ciclopentanos/síntese química , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Indometacina/farmacologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Estrutura Molecular , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Sulfonamidas/síntese química , Sulfonas/síntese químicaRESUMO
Cytokines are believed to regulate Ig class switching, in part, through selective modulation of germ-line constant heavy (CH) gene transcription. B cell activators such as LPS or activated T cell membranes also influence germ-line CH RNA expression in the absence of exogenous cytokines. In this report we determined whether multivalent Ag receptor cross-linking, utilizing dextran-conjugated anti-IgD Abs (alpha delta-dex), could also regulate germ-line CH RNA expression. We demonstrated that alpha delta-dex markedly inhibited germ-line epsilon RNA expression, but strongly augmented germ-line gamma 1 RNA, in LPS + IL-4-stimulated cultures. This was correlated with > 90% alpha delta-dex-mediated suppression in the secretion of IgE and generation of membrane (m)IgE+ cells, and a more modest 50% reduction in IgG1 synthesis and mIgG1+ cells. Furthermore, alpha delta-dex inhibited the LPS induction of both gamma 3 and gamma 2b germ-line RNA and the associated secretion of IgG3 and IgG2b. A similar alpha delta-dex-mediated suppression of germ-line gamma 2a RNA and IgG2a secretion in LPS + IFN-gamma-stimulated cultures was observed. By contrast, activation of resting B cells with alpha delta-dex alone led to induction of germ-line gamma 3, gamma 1, and gamma 2b RNA but did not stimulate detectable expression of RNA specific for gamma 2a or epsilon. These studies demonstrate that: 1) germ-line gamma 1 gene expression is regulated uniquely, 2) germ-line transcription and switch recombination can be dissociated, 3) the germ-line transcription of each IgG isotype has an independent pattern of regulation, and 4) cross-linking of the Ag receptor, by itself, can stimulate small amounts of germ-line CH RNA.
Assuntos
Regulação da Expressão Gênica/imunologia , Rearranjo Gênico do Linfócito B/imunologia , Switching de Imunoglobulina/imunologia , Animais , Linfócitos B/imunologia , Northern Blotting , Células Cultivadas , Dextranos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Regiões Constantes de Imunoglobulina/biossíntese , Imunoglobulina D/imunologia , Cadeias Pesadas de Imunoglobulinas/biossíntese , Interferon gama/fisiologia , Interleucina-4/fisiologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos DBA , RNA Mensageiro/biossíntese , Endonucleases Específicas para DNA e RNA de Cadeia SimplesAssuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Ciclopentanos/farmacologia , Administração Oral , Animais , Artrite Experimental/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/administração & dosagem , Inibidores de Ciclo-Oxigenase/síntese química , Ciclopentanos/administração & dosagem , Ciclopentanos/síntese química , Camundongos , RatosRESUMO
The switch in expression by B cells from IgM to IgG, IgE, or IgA is accomplished by a DNA deletion. The deletion event is regulated, in that specific cytokines direct the B cell to switch to one, or sometimes two, of the six possible murine heavy chain genes. Prior to switch recombination, cytokine treatment also induces the transcription of the constant, switch, and upstream regions of the targeted heavy chain. Much evidence indicates that IFN-gamma directs switch recombination to the murine gamma 2a gene. By developing probes specific for the gamma 2a gene, we demonstrate that IFN-gamma increases germline transcription of this gene in both normal B cells and in the 18.81.A20 pre-B lymphoma. We have obtained cloned copies of three different germline gamma 2a transcripts, each with a different donor splice site. We have also located the 5' ends of these transcripts. The vast majority of the germline gamma 2a transcripts have a long first exon (> 700 bp), consistent with observations by Severinson and her colleagues.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Genes de Imunoglobulinas , Cadeias gama de Imunoglobulina/genética , Interferon gama/farmacologia , RNA Mensageiro/química , Animais , Sequência de Bases , Éxons , Lipopolissacarídeos/farmacologia , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/genéticaAssuntos
Engenharia Biomédica , Departamentos Hospitalares , Garantia da Qualidade dos Cuidados de Saúde , Engenharia Biomédica/economia , Engenharia Biomédica/instrumentação , Engenharia Biomédica/organização & administração , Falha de Equipamento , Segurança de Equipamentos , Equipamentos e Provisões Hospitalares , Departamentos Hospitalares/economia , Departamentos Hospitalares/organização & administração , Serviço Hospitalar de Engenharia e Manutenção/economia , Serviço Hospitalar de Engenharia e Manutenção/organização & administração , Desenvolvimento de Programas , Garantia da Qualidade dos Cuidados de Saúde/economia , Garantia da Qualidade dos Cuidados de Saúde/organização & administraçãoRESUMO
The autosomal recessive mutation mnd2 results in early onset motor neuron disease with rapidly progressive paralysis, severe muscle wasting, regression of thymus and spleen, and death before 40 days of age. mnd2 has been mapped to mouse chromosome 6 with the gene order: centromere-Tcrb-Ly-2-Sftp-3-D6Mit4-mnd2-D6Mit 6, D6Mit9-D6Rck132-Raf-1, D6Mit11-D6Mit12-D6Mit14, mnd2 is located within a conserved linkage group with homologs on human chromosome 2p12-p13. Spinal motor neurons of homozygous affected animals are swollen and stain weakly, and electromyography revealed spontaneous activity characteristic of muscle denervation. Myelin staining was normal throughout the neuraxis. The clinical observations are consistent with a primary abnormality of lower motor neuron function. This new animal model will be of value for identification of a genetic defect responsible for motor neuron disease and for evaluation of new therapies.
Assuntos
Modelos Animais de Doenças , Doença dos Neurônios Motores/genética , Mutação , Animais , Mapeamento Cromossômico , Eletrofisiologia , Heterozigoto , Humanos , Filamentos Intermediários/patologia , Tecido Linfoide/patologia , Camundongos , Camundongos Endogâmicos C57BL , Doença dos Neurônios Motores/patologia , Neurônios Motores/patologia , Fosforilação , Medula Espinal/patologia , Fatores de TempoRESUMO
A series of 5-[1-[4-[(4,5-disubstituted-1H-imidazol-1-yl)methyl]- substituted]-1H-pyrrol-2-yl]-1H-tetrazoles and 5-[1-[4-[(3,5-dibutyl-1H-1,2,4-triazol-1-yl)methyl]-substituted]- 1H-pyrrol-2-yl]-1H-tetrazoles were investigated as novel AT1-selective angiotensin II receptor antagonists. Computer-assisted modeling techniques were used to evaluate structural parameters in comparison to the related biphenyl system. New synthetic procedures have been developed to prepare the novel compounds. The best antagonists in this series had IC50 values (rat uterine membrane receptor binding) in the 10(-8) M range and corresponding pA2 in isolated organ assay (rabbit aorta rings). Structure-activity relationships indicate some similarities with the finding in the biphenyl system. Substitution on the pyrrole ring modulates activity. Compound 5 antagonized angiotensin-induced blood pressure increase when administered to conscious rat at 30 mg/kg per os.
Assuntos
Angiotensina II/antagonistas & inibidores , Antagonistas de Receptores de Angiotensina , Pirróis/síntese química , Animais , Sítios de Ligação/efeitos dos fármacos , Feminino , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Pirróis/metabolismo , Pirróis/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley , Receptores de Angiotensina/metabolismo , Relação Estrutura-Atividade , Útero/efeitos dos fármacos , Útero/metabolismoRESUMO
Females of the scarabaeid beetleCyclocephala lurida produce a volatile sex pheromone which attracts conspecific males. Field experiments demonstrated that larvae of both sexes also emit volatile chemicals that stimulate similar responses in adult males, including attempts by the attracted males to mate with the nonreproductive immature stage. Significantly more adult males were caught in traps baited with conspecific male or female larvae or adult females than in blank control traps. Hexane extracts of both male and female grubs were at least as effective as live larvae in trapping male adults, demonstrating that the behavioral responses are mediated by volatile chemicals. Sensory and behavioral responses of males to sex pheromones emitted by adult females are part of the functional communication system. However, their response to grubs is not functional, because grubs are normally temporally and spatially inaccessible to mate-seeking males. In theory, the evolution of a communication system is problematic because it requires the development of a signal in one sex and the sensory and behavioral attributes to respond to that signal in the other sex. The ontogeny of sex pheromone communication inC. lurida suggests a partial solution to this evolutionary problem. We propose that this sex pheromone communication system is probably derived from noncommunicative volatile chemicals that are lost in adult males and retained by adult females.