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INTRODUCTION: There is limited evidence on the costs and outcomes of patients with aphasia after stroke. The aim of this study was to estimate costs in patients with aphasia after stroke according to the aphasia therapies provided. METHODS: A three-arm, prospective, randomized, parallel group, open-label, blinded endpoint assessment trial conducted in Australia and New Zealand. Usual ward-based care (Usual Care) was compared to additional usual ward-based therapy (Usual Care Plus) and a prescribed and structured aphasia therapy program in addition to Usual Care (the VERSE intervention). Information about healthcare utilization and productivity were collected to estimate costs in Australian dollars for 2017-18. Multivariable regression models with bootstrapping were used to estimate differences in costs and outcomes (clinically meaningful change in aphasia severity measured by the WAB-R-AQ). RESULTS: Overall, 202/246 (82%) participants completed follow-up at 26 weeks. Median costs per person were $23,322 (Q1 5,367, Q3 52,669, n = 63) for Usual Care, $26,923 (Q1 7,303, Q3 76,174, n = 70) for Usual Care Plus and $31,143 (Q1 7,001. Q3 62,390, n = 69) for VERSE. No differences in costs and outcomes were detected between groups. Usual Care Plus was inferior (i.e. more costly and less effective) in 64% of iterations, and in 18% was less costly and less effective compared to Usual Care. VERSE was inferior in 65% of samples and less costly and less effective in 12% compared to Usual Care. CONCLUSION: There was limited evidence that additional intensively delivered aphasia therapy within the context of usual acute care provided was worthwhile in terms of costs for the outcomes gained.
Assuntos
Afasia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Análise Custo-Benefício , Estudos Prospectivos , Fala , Austrália , Afasia/etiologia , Afasia/reabilitaçãoRESUMO
BACKGROUND: Recent studies have suggested that the birth order effect in allergy may be established during the prenatal period and that the protective effect may originate in the mother. HLA class II disparity between mother and foetus has been associated with significantly increased Th1 production. In this study, we investigated whether production of HLA antibodies 4 years after pregnancy with index child is associated with allergic outcomes in offspring at 8 years. METHODS: Anti-HLA class I and II antibodies were measured in maternal serum (n = 284) and levels correlated to numbers of pregnancies and birth order, and allergic outcomes in offspring at 8 years of age. RESULTS: Maternal anti-HLA class I and II antibodies were significantly higher when birth order, and the number of pregnancies were larger. Anti-HLA class II, but not class I antibodies were associated with significantly less atopy and seasonal rhinitis in the offspring at age 8 years. Mothers with nonatopic (but not atopic) offspring had a significant increase in anti-HLA class I and II antibodies with birth order. CONCLUSION: This study suggests that the 'birth order' effect in children may be due to parity-related changes in the maternal immune response to foetal antigens. We have observed for the first time an association between maternal anti-HLA class II antibodies and protection from allergy in the offspring. Further work is required to determine immunologically how HLA disparity between mother and father can protect against allergy.
Assuntos
Anticorpos/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Hipersensibilidade/imunologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Adulto , Anticorpos/sangue , Criança , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Hipersensibilidade/prevenção & controle , Masculino , Gravidez , Fatores de RiscoRESUMO
BACKGROUND: People with communication disabilities post-stroke have poor quality-of-life. OBJECTIVES: We aimed to explore the association of self-reported communication disabilities with different dimensions of quality-of-life between 90 and 180 days post-stroke. METHODS: Cross-sectional survey data were obtained between 90 and 180 days post-stroke from registrants in the Australian Stroke Clinical Registry recruited from three hospitals in Queensland. The usual follow-up survey included the EQ5D-3L. Responses to the Hospital Anxiety and Depression Scale, and extra questions (e.g. communication disabilities) were also collected. We used χ2 statistics to determine differences. RESULTS: Overall, 244/647 survivors completed the survey. Respondents with communication disabilities (n = 72) more often reported moderate to extreme problems in all EQ5D-3L dimensions, than those without communication disabilities (n = 172): anxiety or depression (74% vs 40%, p < .001), pain or discomfort (58% vs 39%, p = .006), self-care (46% vs 18%, p < .001), usual activities (77% vs 49%, p < .001), and mobility (68% vs 35%, p < .001). Respondents with communication disabilities reported less fatigue (66% vs 89%, p < .001), poorer cognitive skills (thinking) (16% vs 1%, p < .001) and lower social participation (31% vs 6%, p < .001) than those without communication disabilities. CONCLUSIONS: Survivors of stroke with communication disabilities are more negatively impacted across different dimensions of quality-of-life (as reported between 90 and 180 days post-stroke) compared to those without communication disabilities. This highlights the need for timely and on-going comprehensive multidisciplinary person-centered support.
Assuntos
Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia , Estudos Transversais , Austrália , Qualidade de Vida/psicologia , Sobreviventes/psicologiaRESUMO
BACKGROUND/AIMS: Pulmonary arterial hypertension (PAH) frequently accompanies childhood congenital heart disease (CHD) and may persist into adult life. The advent of specific PAH therapies for PAH prompted formation of a national Australian and New Zealand registry in 2010 to document the incidence, demographics, presentation and outcomes for these patients. METHODS: This multicentre, prospective, web-based registry enrols patients with CHD-associated PAH being followed in a tertiary centre. The inclusion criteria stipulated patient age ≥16 years, a measured mean pulmonary arterial pressure >25 mmHg at rest or echocardiographical evidence of PAH or a diagnosis of Eisenmenger syndrome, and followed since 1 January 2000. A single observer collected standardised data during a series of site visits. RESULTS: Of the first 50 patients enrolled, 30 (60%) were female. The mean age (standard deviation (SD)) at the time of PAH diagnosis or confirmation in an adult centre was 27.23 (10.07) years, and 32 (64%) patients are currently aged >30 years. Fourteen (28%) patients were in World Health Organization Functional Class II and 36 (72%) in Class III at the time of diagnosis. Forty-seven of 50 (94%) had congenital systemic-pulmonary shunts, and 36 (72%) never underwent intervention. Thirteen (26%) had Down syndrome. Confirmation of PAH by recent cardiac catheterisation was available in 30 (60%) subjects. During follow up, a total of 32 (64%) patients received a PAH-specific therapy. CONCLUSIONS: CHD associated with PAH in adult life has resulted in a new population with unique needs. This registry will allow documentation of clinical course and long-term outcomes for these patients.
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Cardiopatias Congênitas/epidemiologia , Hipertensão Pulmonar/epidemiologia , Sistema de Registros , Adulto , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/terapia , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/terapia , Masculino , Estudos Prospectivos , Adulto JovemRESUMO
Milrinone is a bipyridine phosphodiesterase inhibitor with positive inotropic and vasodilatory effects. As interest in longer term use of intravenous therapy increases, it becomes essential to monitor its plasma concentration owing to a narrow therapeutic range, an increased half-life in renal failure and toxicity associated with high levels. A high-performance liquid chromatography (HPLC) method with mass (MS) detection using a triple quadrupole mass spectrometer is presented. The method was compared with the UV/HPLC method and validated according to current international guidelines. Coefficients of variation of less than 7.5% were obtained across the therapeutic range and 18.3% at 2.4 ng/mL, the lower limit of quantitation. Plasma from 13 cardiac surgery patients receiving standard intravenous doses of milrinone were measured. Eight patients achieved therapeutic milrinone levels within 3-4 h post start of infusion, one was borderline sub-therapeutic and four patients achieved levels that were above the upper limit of the therapeutic range and potentially toxic. This method offers high sensitivity, is rapid, easy to use and requires minimal amount of sample. We believe this method could become the reference procedure for clinical monitoring of milrinone and help to improve the safety of the use of this drug in patients with cardiac failure.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Milrinona/sangue , Monitoramento de Medicamentos/métodos , Estabilidade de Medicamentos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/cirurgia , Humanos , Modelos Lineares , Milrinona/administração & dosagem , Milrinona/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Preformed donor HLA-specific antibodies are a known indicator for poor patient survival after cardiac transplantation. The role of de novo donor-specific antibodies (DSA) formed after cardiac transplantation is less clear. Here we have retrospectively analyzed 243 cardiac transplant recipients, measuring HLA antibody production every year after transplantation up to 13 years post-transplant. Production of de novo DSA was analyzed in patients who had been negative for DSA prior to their transplant. DSA including transient antibodies were associated with poor patient survival (p = 0.0018, HR = 3.198). However, de novo and persistent DSA was strongly associated with poor patient survival (p = 0.0001 HR = 4.351). Although complement fixing persistent DSA correlated with poor patient survival, this was not increased compared to noncomplement fixing persistent DSA. Multivariable analysis indicated de novo persistent DSA to be an independent predictor of poor patient survival along with HLA-DR mismatch and donor age. Only increasing donor age was found to be an independent risk factor for earlier development of CAV. In conclusion, patients who are transplanted in the absence of pre-existing DSA make de novo DSA after transplantation which are associated with poor survival. Early and regular monitoring of post-transplant DSA is required to identify patients at risk of allograft failure.
Assuntos
Antígenos HLA/imunologia , Transplante de Coração/efeitos adversos , Transplante de Coração/imunologia , Isoanticorpos/biossíntese , Adulto , Especificidade de Anticorpos , Testes de Fixação de Complemento , Feminino , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Antígenos HLA-DR/imunologia , Transplante de Coração/mortalidade , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Doadores de TecidosRESUMO
Little is known about the effect of MICA antibodies (Abs) on cardiac allograft function and survival. Pretransplant and posttransplant serum from 491 and 196 adult cardiac allograft recipients, respectively, has been investigated for MICA Abs, donor specificity and the effect of MICA Abs on graft survival, acute rejection episodes (AR) and cardiac allograft vasculopathy (CAV). Patients with HLA Abs (11.6%) were excluded from the analysis. A total of 11.8% of patients had MICA Abs, without HLA Abs, before their transplant. Actuarial graft survival demonstrated slightly better survival of patients with donor-specific MICA Abs at 1 and 5 years (88.9% and 83.3%) than patients negative for MICA Abs (72% and 63.7%, p = 0.051). After transplantation, 15.8% of patients produced MICA Abs, and in 17 patients these were produced de novo. There was no effect of pretransplant or posttransplant production of MICA Abs on numbers of AR episodes in year 1, or CAV assessed at years 3 and 5. Immunocytochemistry of cardiac biopsies from 11 patients did not demonstrate a presence of MICA. Sera from only 4/69 patients with MICA Abs fixed complement prior to transplantation and from 7/38 patients following transplantation. In conclusion, this study suggests that MICA Abs do not adversely affect the outcome of cardiac transplantation.
Assuntos
Anticorpos/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Adulto , Anticorpos/sangue , Biópsia , Estudos de Coortes , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/imunologia , Miocárdio/patologia , Estudos Retrospectivos , Transplante Homólogo , Resultado do TratamentoRESUMO
Anti-vimentin antibodies (AVA) are associated with autoimmunity and solid organ transplantation, conditions associated with vascular disease, but their contribution to disease pathogenesis is unknown. Here, we have examined interactions between AVA (mAb and serum from patients) and various leukocyte populations using whole blood and flow cytometry. Normal blood treated with patient sera containing high AVA-IgM titers or with a vimentin-specific monoclonal IgM led to activation of platelets and other leukocytes, as demonstrated by induced expression of P-selectin, fibrinogen, tissue factor, and formation of platelet:leukocyte (P:L) conjugates and a reduction in platelet counts. This activity was antigen (vimentin)-specific and was not mediated by irrelevant IgM antibodies. Flow cytometry demonstrated that AVA do not bind directly to resting platelets in whole blood, but they bind to approximately 10% of leukocytes. Supernatant, derived from AVA-treated leukocytes, induced platelet activation, as measured by the generation of platelet microparticles, when added to platelet-rich plasma. When AVA were added to whole blood in the presence of CV-6209, a platelet-activating factor (PAF) receptor inhibitor, platelet depletion was inhibited. This suggests that PAF is one of the mediators released from AVA-activated leukocytes that leads to P:L conjugation formation and platelet activation. In summary, AVA bind to leukocytes, resulting in release of a PAF and prothrombotic factor that exert a paracrine-activating effect on platelets. Overall, this proposed mechanism may explain the pathogenesis of thrombotic events in autoimmune diseases associated with AVA.
Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/sangue , Plaquetas/imunologia , Imunoglobulina M/imunologia , Leucócitos/imunologia , Fator de Ativação de Plaquetas/fisiologia , Ativação Plaquetária/imunologia , Trombofilia/etiologia , Vimentina/imunologia , Apoptose/imunologia , Autoanticorpos/sangue , Doenças Autoimunes/complicações , Doenças Autoimunes/imunologia , Adesão Celular/imunologia , Complemento C3d/metabolismo , Meios de Cultivo Condicionados/farmacologia , Fibrinogênio/metabolismo , Humanos , Imunoglobulina M/sangue , Técnicas de Imunoadsorção , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Selectina-P/metabolismo , Fator de Ativação de Plaquetas/metabolismo , Compostos de Piridínio/farmacologia , Proteínas Recombinantes/imunologia , Tromboplastina/metabolismo , Vimentina/genéticaRESUMO
Experimental studies have suggested that protective genes protect allografts from cardiac allograft vasculopathy (CAV), the major complication after cardiac transplantation. Here we have sought to confirm this hypothesis using long-term heart transplant recipients. Twenty-two patients that were 9 years or older after transplant were investigated; 11 of these were without angiographic evidence of CAV; 11 had developed early CAV at 1 to 3 years after transplant. To identify proteins that may act as protectors from CAV, a global proteomic approach was used comparing cardiac biopsies from 12 patients taken within the first 2 weeks after transplant and those taken after 9 years from the same patient. Proteins were separated by 2-D gel-electrophoresis, detected by silver staining, and analyzed using Progenesis software. A particular protein spot was found in 4/6 biopsies from patients without CAV, but absent from 5/6 biopsies from those with CAV (P=0.24); however, quantitative analysis of spot intensity showed a significant difference (0.061+/-0.05 versus 0.003+/-0.01, P=0.04). This spot was identified by mass spectrometry and a combination of techniques as a diphosphorylated form of HSP27. Immunohistochemistry of further biopsies not only validated that HSP27 was more abundantly expressed on biopsies without CAV but also showed it to be localized to blood vessels. In contrast, vessels from patients with CAV did not express HSP27 (P=0.028x10(-4)). Immunohistochemistry of 12 further early biopsies and nontransplanted heart showed HSP27 to be present in normal blood vessels. These findings suggest that expression of a specific diphosphorylated form of HSP27 is associated with healthy blood vessels; it appears to be lost from vessels of patients with graft vasculopathy.
Assuntos
Doença da Artéria Coronariana/prevenção & controle , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Proteínas de Choque Térmico/fisiologia , Apoptose , Biópsia , Angiografia Coronária , Doença da Artéria Coronariana/etiologia , Vasos Coronários/patologia , Rejeição de Enxerto/etiologia , Proteínas de Choque Térmico/análise , Humanos , Imuno-Histoquímica , FosforilaçãoRESUMO
In a previous study (G. M. Wahl, B. Robert de Saint Vincent, and M. L. De Rose, Nature (London) 307:516-520, 1984), we used gene transfer of a CAD cosmid to demonstrate that gene position profoundly affects amplification frequency. One transformant, T5, amplified the donated CAD genes at a frequency at least 100-fold higher than did the other transformants analyzed. The CAD genes in T5 and two drug-resistant derivatives were chromosomally located. In this report, we show that a subclone of T5 gives rise to an extrachromosomal molecule (CAD episome) containing the donated CAD genes. Gel electrophoresis indicated that the CAD episome is approximately 250 to 300 kilobase pairs, and a variety of methods showed that it is a covalently closed circle. We show that the CAD episome replicates semiconservatively and approximately once per cell cycle. Since the CAD cosmid, which comprises most of the CAD episome, does not replicate autonomously when transfected into cells, our results indicate that either the process which generated the episome resulted in a cellular origin of DNA replication being linked to the CAD sequences or specific rearrangements within the episome generated a functional origin. The implications of these results for mechanisms of gene amplification and the genesis of minute chromosomes are discussed.
Assuntos
Replicação do DNA , Amplificação de Genes , Genes Reguladores , Complexos Multienzimáticos/genética , Plasmídeos , Proteínas/genética , Animais , Aspartato Carbamoiltransferase/genética , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Mapeamento Cromossômico , Cosmídeos , Cricetinae , Enzimas de Restrição do DNA , Di-Hidro-Orotase/genética , Cariotipagem , TransfecçãoRESUMO
INTRODUCTION: Nearly 15% of youth in India use tobacco. However, few studies have explored the use, knowledge, and attitudes of smokeless tobacco use among youth. AIM: To determine the patterns of use as well as knowledge and perceptions of smokeless tobacco among youth in Mumbai attending municipal schools. MATERIALS AND METHODS: A cross-sectional survey was performed among 1053 students in the 8th and 9th grades in 16 municipal schools in Mumbai to determine the knowledge and perceptions about smokeless tobacco products as well as the patterns of use. RESULTS AND CONCLUSIONS: Ever use of smokeless tobacco was reported by 47 (4.7%) students in the survey. Twenty-nine (2.9%) students reported ever using smoked tobacco. Students were more likely to identify cigarettes and bidis as tobacco products compared to smokeless tobacco products such as gutkha, mishri, and khaini. Betel nut products were used by 178 (17.9%) students. The high rate of smokeless tobacco and betel nut use coupled with low levels of knowledge about their contents and harms suggests that tobacco control programs targeting youth should ensure that these products are adequately explained and understood by students.
Assuntos
Areca/efeitos adversos , Tabaco sem Fumaça/efeitos adversos , Estudos Transversais , Feminino , Humanos , Índia , Masculino , Instituições Acadêmicas , EstudantesRESUMO
BACKGROUND: The purpose of this study was to determine whether T cells with indirect allospecificity could be detected in heart transplant recipients with chronic rejection. METHOD AND RESULTS: Human T-cell clones were used to determine the most effective way to deliver major histocompatibility complex alloantigens for indirect presentation. Seven allograft recipients with evidence of progressive, chronic rejection were selected. Four heart graft recipients with no evidence of chronic rejection were used as controls. Peripheral blood T cells and antigen-presenting cells from the recipients were cultured with frozen/thawed stored donor cells or major histocompatibility complex class I-derived synthetic peptides in limiting dilution cultures and then compared with controls using tetanus toxoid and frozen/thawed third-party cells with no human leukocyte antigens in common with the donor. In 5 of 7 patients analyzed who had chronic rejection, elevated frequencies of T cells with indirect, anti-donor specificity (iHTLf) were detected. No such elevated iHTLf were detected in recipients without chronic rejection. DISCUSSION: iHTLf can be obtained from human transplant recipients, which supports the contention that the indirect pathway is involved in chronic transplant rejection.
Assuntos
Epitopos , Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Linfócitos T/imunologia , Doadores de Tecidos , Animais , Linhagem Celular , Doença Crônica , Drosophila , Antígeno HLA-A2/imunologia , Humanos , Isoantígenos/imunologia , Fragmentos de Peptídeos/imunologiaRESUMO
OBJECTIVES: This study was designed to investigate the organ and disease specificity of antiheart antibodies in patients with dilated cardiomyopathy. BACKGROUND: Autoimmune disease is characterized by the presence of circulating autoantibodies, and autoimmune mechanisms may play a role in the pathogenesis of dilated cardiomyopathy. METHODS: An SDS-PAGE (sodium dodecylsulfate polyacrylamide gel electrophoresis) procedure followed by Western blotting was used to screen serum samples for antiheart antibodies of two immunoglobulin classes, IgM and IgG, from 52 patients with dilated cardiomyopathy and 48 patients with ischemic heart disease as control subjects. Use of two-dimensional gel electrophoresis followed by Western blotting and protein sequencing enabled us to identify the protein bands against which antiheart antibodies were produced in both groups of patients. RESULTS: Strong IgG antiheart antibodies against myocardial proteins, cross-reacting with skeletal muscle proteins, were detected in significantly more patients with dilated cardiomyopathy (n = 24 [46%]) than with ischemic heart disease (n = 8 [17%]) (p = 0.001). Patients with dilated cardiomyopathy showed a significantly greater frequency and reactivity of IgG antiheart antibodies against six myocardial proteins (molecular weight 30, 35, 40, 60, 85 and 200 kD) than did patients with ischemic heart disease. These were identified as myosin light chain 1, tropomyosin, actin, heat shock protein (HSP)-60, an unidentified protein and myosin heavy chain, respectively. CONCLUSIONS: We detected strong IgG antiheart antibodies in significantly more patients with dilated cardiomyopathy than with ischemic heart disease. The most immunogenic band was that corresponding to HSP-60. Antibodies against HSP-60 were found in 85% and 42% of patients with dilated cardiomyopathy and ischemic heart disease, respectively, confirming our hypothesis of an immune involvement in dilated cardiomyopathy.
Assuntos
Autoanticorpos/sangue , Cardiomiopatia Dilatada/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Isquemia Miocárdica/sangue , Miocárdio/imunologia , Actinas/química , Actinas/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Autoanticorpos/imunologia , Western Blotting , Cardiomiopatia Dilatada/epidemiologia , Cardiomiopatia Dilatada/imunologia , Estudos de Casos e Controles , Chaperonina 60 , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Feminino , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/imunologia , Humanos , Masculino , Dados de Sequência Molecular , Peso Molecular , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/imunologia , Quinase de Cadeia Leve de Miosina/química , Quinase de Cadeia Leve de Miosina/imunologia , Miosinas/química , Miosinas/imunologia , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Tropomiosina/química , Tropomiosina/imunologiaRESUMO
Human endothelial activity of ecto-5'-nucleotidase (E5'N) is several times higher than in pig endothelial cells. This may have implication for xenotransplantation due to the role this enzyme plays in conversion of pro-inflammatory and pro-aggreggatory nucleotides into anti-inflammatory and antiaggregatory adenosine. We have shown in this study that human E5'N can be functionally expressed in pig endothelial cells leading to increased adenosine production from both extracellular AMP and ATP. We suggest that E5'N expression in transgenic pigs for xenotransplantation may help to prolong graft survival.
Assuntos
5'-Nucleotidase/biossíntese , 5'-Nucleotidase/química , Adenosina/metabolismo , Endotélio Vascular/citologia , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular , Células Cultivadas , DNA Complementar/metabolismo , Endotélio Vascular/metabolismo , Sobrevivência de Enxerto , Humanos , Inflamação/patologia , Suínos , Fatores de Tempo , Transplante HeterólogoRESUMO
OBJECTIVE: Intercellular adhesion molecule (ICAM)-1 is an immunoglobulin-like cell adhesion molecule expressed by several cell types, including proliferating vascular smooth muscle cells (VSMC). Cross-linking ICAM-1 on the surface of different cell types has previously been shown to cause an increase in cellular activation within the cytoplasm. Here, our objective was to examine events following ligation of ICAM-1 on the surface of human VSMC. METHODS: VSMC were isolated by explant from human pulmonary arteries or aortic tissue from cardiac transplant donors. ICAM-1 was ligated with monoclonal antibodies, followed by cross-linking with a secondary antibody. Activation of signalling pathways, proliferation and expression of a second adhesion molecule, vascular cell adhesion molecule (VCAM)-1 were investigated. RESULTS: ICAM-1 cross-linking caused an increase in activation of extracellular regulated kinase (Erk)-1/-2 and Jun N-terminal kinase (JNK)-1/-2. mRNA and protein for VCAM-1 was observed after ICAM-1 cross-linking, and this was abrogated by addition of an upstream inhibitor of Erk-1/-2, PD98059. No increase in cell proliferation was observed. CONCLUSIONS: Ligation of ICAM-1 on the surface of vascular smooth muscle cells in vitro, leads to the expression of adhesion molecules associated with monocyte infiltration, but does not contribute to smooth muscle cell proliferation. In vivo, this might lead to prolongation of the inflammatory response within diseased blood vessels, by arresting monocytes within atherosclerotic plaques.
Assuntos
Molécula 1 de Adesão Intercelular/metabolismo , Proteínas Musculares/metabolismo , Músculo Liso Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Comunicação Celular/fisiologia , Técnicas de Cultura de Células , Divisão Celular/fisiologia , Regulação da Expressão Gênica , Humanos , Músculo Liso Vascular/citologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Molécula 1 de Adesão de Célula Vascular/genéticaRESUMO
Peroxisome proliferators are nongenotoxic rodent carcinogens that act as tumor promoters by increasing cell proliferation; however, their precise mechanism of action is not well understood. Oxidative DNA damage caused by leakage of hydrogen peroxide (H2O2) from peroxisomes was hypothesized initially as the mechanism by which these compounds cause liver tumors. It seems unlikely that oxidants of peroxisomal origin explain the mechanism of action of peroxisome proliferators because treatment with these compounds in vivo does not lead to increased H2O2 production. On the other hand, Kupffer cell-derived oxidants, such as superoxide, may play a role in initiating tumor nerosis factor-alpha (TNF-alpha) production that leads to hepatocyte proliferation. Peroxisome proliferators have been shown to activate Kupffer cells both in vitro and in vivo, and the use of Kupffer cell inhibitors such as methyl palmitate and dietary glycine have demonstrated that Kupffer cells are responsible for hepatocyte proliferation by mechanisms involve TNF-alpha. Moreover, peroxisome proliferators activate the transcription factor NF-kappaB, one of the major regulators of TNF-alpha expression, in Kupffer cells. Importantly, activation of NF-kappaB by peroxisome proliferators was shown to be oxidant-dependent, leading to the hypothesis that oxidants of Kupffer cell origin are involved in the mechanism of action. Many of the effects of peroxisome proliferators, including peroxisome induction and hepatomegaly, involve the peroxisome proliferator-activated receptor-alpha (PPARalpha). Recently, it was shown that peroxisome proliferator-induced cell proliferation and tumors require the PPARalpha. However, PPARalpha is not involved in TNF-alpha production by Kupffer cells because it is not expressed in this cell type. How it is involved in liver tumor remains unclear and one possible explanation is that both Kupffer cell TNF-alpha and parenchymal cell PPARalpha are required. Collectively, recent data are consistent with the hypothesis that oxidants play a role in signaling hepatocellular proliferation due to peroxisome proliferators via activation of NF-kappaB and incrase in mitogenic cytokines such as TNF-alpha.
Assuntos
Oxidantes/fisiologia , Proliferadores de Peroxissomos , Animais , Divisão Celular , Dano ao DNA , Humanos , Fígado/citologia , Neoplasias Hepáticas/metabolismo , Camundongos , Modelos Biológicos , Ratos , Espécies Reativas de Oxigênio , Receptores Citoplasmáticos e Nucleares/metabolismo , Especificidade da Espécie , Fatores de Transcrição/metabolismoRESUMO
L-selenomethionine (SeM), an analogue of methionine containing Se, is incorporated by mouse and rat lymphocytes in vitro: labelled with 75Se (75SeM) it emits gamma-rays distinguishable in energy from those of 125I and 51Cr. The usefulness of 75SeM for lymphocyte localisation studies was investigated. Both B and T cells incorporated 75SeM. Reutilization of the isotope in the mouse after injection of killed cells or allogeneic cells into immunized recipients was 1-2% of the injected dose. The immunocompetence of labelled mouse T and B cells was assessed in irradiated recipients, no effect of 75SeM incorporation being found. The distribution of labelled lymphocytes from various tissues in syngeneic recipients was found to be comparable to that previously obtained with 51Cr.
Assuntos
Linfócitos/metabolismo , Selênio , Selenometionina , Animais , Cortisona/farmacologia , Congelamento , Linfonodos/citologia , Ativação Linfocitária , Linfócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Baço/citologia , Linfócitos T/imunologia , Timo/citologiaRESUMO
BACKGROUND: The role played by major histocompatibility complex (MHC) class II-positive vascular endothelial cells in organ graft rejection is unknown but potentially very important. Methods. The MHC class II-negative porcine vascular endothelial cell line PIEC was stably transfected with the human class II transactivator CIITA, in order to induce MHC class II expression without the coinduction of T-cell costimulatory ligands. These PIEC cells were compared with interferon gamma-treated PIEC cells for their capacity to stimulate the proliferation of pure human CD4+ T cells. Results. The CIITA-transfected PIECs were as effective as interferon y-treated PIECs for stimulating unprimed human CD4+ T cells, the peak response with the CIITA-transfected cells in fact occurring earlier (day 3 instead of day 5). Monoclonal antibodies to SLA-DR substantially inhibited the CD4+ T-cell responses in both cases. However, whereas the response to interferon gamma-treated PIEC was partially inhibited by CTLA4-Ig, that to CIITA-transfected PIEC was not. Conclusions. The strong stimulation of CD4+ T cells by the specific induction of MHC class II antigens demonstrates that PIEC cells constitutively express functionally effective levels of costimulatory ligands. This finding strengthens the case that vascular endothelial cells are professional antigen-presenting cells and that MHC class II-positive vascular endothelial cells might play a role in the rejection of organ allografts.
Assuntos
Linfócitos T CD4-Positivos/fisiologia , Endotélio Vascular/fisiologia , Antígenos de Histocompatibilidade Classe II/fisiologia , Imunoconjugados , Ativação Linfocitária , Proteínas Nucleares , Abatacepte , Animais , Anticorpos/farmacologia , Antígenos CD , Antígenos de Diferenciação/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Antígeno CTLA-4 , Linhagem Celular , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunossupressores/farmacologia , Interferon gama/farmacologia , Suínos , Transativadores/fisiologia , TransfecçãoRESUMO
Immunocytochemical techniques have been used to investigate the expression of common determinants of class I, common determinants of class II and DR, DP, and DQ antigens on frozen sections from twenty normal donor lungs, three lungs resected due to carcinoma and nine lungs removed from heart/lung recipients who were undergoing retransplant due to obliterative bronchiolitis. In all lungs, alveolar macrophages expressed common determinants of class I and class II, as well as DR, DP and DQ antigens. In normal lung, class I was expressed on all vascular endothelium, all tracheal epithelium and most, but not all, bronchiolar epithelium. Class II was always expressed on tracheal epithelium, but expression on bronchiolar epithelium and vascular endothelium was variable and sometimes absent. In lungs from transplant patients with severe obliterative bronchiolitis, vascular endothelium, in addition to expressing class I, now consistently expressed class II. Epithelium from trachea, bronchioles, and alveoli also consistently expressed class I and class II. To conclude, there is enhanced expression of class II antigens on endothelial and epithelial cells from lungs with obliterative bronchiolitis.
Assuntos
Bronquiolite Obliterante/imunologia , Antígenos HLA-D/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Transplante de Pulmão , Pulmão/imunologia , Brônquios/imunologia , Endotélio Vascular/imunologia , Epitélio/imunologia , Humanos , Imuno-Histoquímica , Complexo Principal de Histocompatibilidade , Alvéolos Pulmonares/imunologia , Traqueia/imunologiaRESUMO
Adhesion of leukocytes to vascular endothelium is a necessary step leading to the migration of cells into underlying tissues. Vascular adhesion molecules regulate this process and may play an important role in graft rejection. Immunocytochemical studies have been used to investigate the expression of vascular adhesion molecules (ICAM-1, PECAM, VCAM-1, and ELAM-1) in normal donor heart (n = 15) and myocardial biopsies from heart transplant patients with acute rejection (n = 15). Sections were also stained with antibodies against endothelium, leukocytes, MHC antigens, and markers of cell activation. In donor heart EN4, vWF, ICAM-1, PECAM, MHC class I--and, to a lesser extent, VCAM-1 and DR antigen--are expressed on arterioles and venules, whereas ELAM-1 and Pal-E are restricted to venules. Expression of Pal-E, VCAM-1, ICAM-1, and DR antigen was increased during rejection. Capillary endothelium normally expresses EN4, ICAM-1, PECAM, MHC class I, and DR antigen but little, if any, VCAM-1 or ELAM-1. During rejection, however, there is an increased expression of all adhesion molecules. This is paralleled by an increased expression of vWF by capillary endothelium. In addition, ICAM-1 like MHC class I antigen is induced on the myocardial membrane and intercalating discs. Endocardium from donor heart expresses EN4, vWF, PECAM, MHC class I, and sometimes Pal-E and ICAM-1, but very little VCAM-1, ELAM-1 or DR antigen. There is an increased expression of Pal-E, ICAM-1, VCAM-1, and DR antigen on endocardium from rejecting heart biopsies. Proliferating Ki-67+ cells and activated T cells expressing the receptor for IL-2 were also found in biopsies during rejection episodes.