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1.
Radiography (Lond) ; 25 Suppl 1: S33-S39, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31481185

RESUMO

INTRODUCTION: Pre-existing studies argue, radiographers are "apathetic" when it comes to research. However, labelling everyone as such seems a gross simplification of a multifaceted issue; especially as current evidence tends to err towards the anecdotal, subjective or is compared to similar professions. Considering this, the SCoR periodically issues a Research Strategy, recognising the necessity to embed/improve research-capacity across all levels of the profession. The aim of this study is to ascertain factors characteristically influencing research-capacity amongst HCPC-registered radiographers in England. METHODS: A purposeful sample of 5 years' bibliometric data from the journal 'Radiography.' A critical and thematic analysis followed based on current peer reviewed journals and grey literature. RESULTS: Of 374 eligible articles and 143 research-active authors (published 2 + articles), collaborations prominently featured (74.9%) across 19 international partnerships. HCPC registrants in England were principal investigator(s) in 49.20% of cases and registrants affiliated with the journal/publisher generally published more than non-affiliates. Preferred topic-areas included 'Education & Research' and 'Technical Practice.' Males published more than females (M = 5.13/F = 3.45). Average length of practice equalled 22.93 years. Outputs mostly originated from HEIs (62.07%), but contributions varied (mean = 10.05/std.deviation = ±17.09); modestly correlating high-REF scoring HEIs (r = 0.330); however, regional workforce ratio(s) proved the strongest indicator (r = 0.601). CONCLUSION: No "one-size-fits all" approach to research-capacity applies; multiple variables affect capacity/activeness. Many seem contingent on extrinsic factors e.g. regional locale, organisational type and culture/support. Personal/professional influences included career status, length of qualification and gender. Future strategies may benefit from refinement; mindful of the dynamics influencing the heterogeneity of the current workforce. Recommendations are that future strategies/studies may benefit from more specific targeting.


Assuntos
Bibliometria , Pesquisa Biomédica/estatística & dados numéricos , Radiografia/estatística & dados numéricos , Inglaterra , Feminino , Humanos , Comunicação Interdisciplinar , Masculino
2.
J Hosp Infect ; 103(4): 382-387, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430534

RESUMO

BACKGROUND: There is a mismatch between research questions which are considered to be important by patients, carers and healthcare professionals and the research performed in many fields of medicine. No relevant studies which have assessed research priorities in healthcare-associated infection (HCAI) that have involved patients' and carers' opinions were identified in the literature. AIM: The Healthcare-Associated Infections Priority Setting Partnership was established to identify the top research priorities in the prevention, diagnosis and treatment of HCAI in the UK, considering the opinions of all these groups. METHODS: The methods broadly followed the principles of the James Lind Alliance (JLA) priority setting activity. FINDINGS: In total, 259 unique valid research questions were identified from 221 valid responses to a consultation of patients, carers and healthcare professionals after seeking their opinions for research priorities. The steering committee of the priority setting partnership rationalized these to 50 unique questions. A literature review established that for these questions there were no recent high-quality systematic reviews, high-quality systematic reviews which concluded that further studies were necessary, or the steering committee considered that further research was required despite the conclusions of recent systematic reviews. An interim survey ranked the 50 questions, and the 10 main research priorities were identified from the top 32 questions by consensus at a final priority setting workshop of patients, carers and healthcare professionals using group discussions. CONCLUSIONS: A priority setting process using JLA methods and principles involving patients, carers and healthcare professionals was used to identify the top 10 priority areas for research related to HCAI. Basic, translational, clinical and public health research would be required to address these uncertainties.


Assuntos
Pesquisa Biomédica , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/prevenção & controle , Pesquisa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecção Hospitalar/terapia , Feminino , Pessoal de Saúde/psicologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pacientes/psicologia , Gravidez , Inquéritos e Questionários , Reino Unido , Adulto Jovem
3.
MMWR Morb Mortal Wkly Rep ; 67(37): 1036-1039, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30235185

RESUMO

Healthy aging is not merely the absence of disease or disability, but requires physical and mental health and ongoing social engagement (1). As the average U.S. life expectancy increases, recognition that public health can play a vital role in promoting healthy, successful aging even in the face of increased prevalence of chronic diseases, including types of dementia, among older adults (i.e., aged ≥65 years) has grown. Furthermore, actively engaging adults in prevention and wellness along with involving their caregivers (i.e., the family and friends of older adults who provide them with unpaid and informal support and services) can serve to prevent or delay the onset of physical disabilities and cognitive decline. Adults often are reluctant to discuss their concerns about worsening memory with their health care providers although such discussions can lead to earlier diagnosis and better care, planning, and support. As advances in public health and health care have helped increase life expectancy, public health professionals and health care providers have the opportunity to improve the quality of life for older adults and their caregivers and reduce the burdens associated with aging.


Assuntos
Atividades Cotidianas , Promoção da Saúde/organização & administração , Saúde Mental , Idoso , Idoso de 80 Anos ou mais , Cuidadores , Centers for Disease Control and Prevention, U.S. , Prática Clínica Baseada em Evidências , Humanos , Prática de Saúde Pública , Estados Unidos
4.
Lung Cancer ; 89(2): 175-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26115838

RESUMO

BACKGROUND: In the UK, despite the import and use of all forms of asbestos being banned more than 15 years ago, the incidence of mesothelioma continues to rise. Mesothelioma is almost invariably fatal, and more research is required, not only to find more effective treatments, but also to achieve an earlier diagnosis and improve palliative care. Following a debate in the House of Lords in July 2013, a package of measures was agreed, which included a James Lind Alliance Priority Setting Partnership, funded by the National Institute for Health Research. The partnership brought together patients, carers, health professionals and support organisations to agree the top 10 research priorities relating to the diagnosis, treatment and care of patients with mesothelioma. METHODS: Following the established James Lind Alliance priority setting process, mesothelioma patients, current and bereaved carers, and health professionals were surveyed to elicit their concerns regarding diagnosis, treatment and care. Research questions were generated from the survey responses, and following checks that the questions were currently unanswered, an interim prioritisation survey was conducted to identify a shortlist of questions to take to a final consensus meeting. FINDINGS: Four hundred and fifty-three initial surveys were returned, which were refined into 52 unique unanswered research questions. The interim prioritisation survey was completed by 202 responders, and the top 30 questions were taken to a final meeting where mesothelioma patients, carers, and health professionals prioritised all the questions, and reached a consensus on the top 10. INTERPRETATION: The top 10 questions cover a wide portfolio of research (including assessing the value of immunotherapy, individualised chemotherapy, second-line treatment and immediate chemotherapy, monitoring patients with pleural thickening, defining the management of ascites in peritoneal mesothelioma, and optimising follow-up strategy). This list is an invaluable resource, which should be used to inform the prioritisation and funding of future mesothelioma research.


Assuntos
Neoplasias Pulmonares , Mesotelioma , Pesquisa , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Mesotelioma/diagnóstico , Mesotelioma/terapia , Mesotelioma Maligno
5.
Diabetologia ; 56(3): 542-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23238790

RESUMO

AIMS/HYPOTHESIS: The paucity of information on the epigenetic barriers that are blocking reprogramming protocols, and on what makes a beta cell unique, has hampered efforts to develop novel beta cell sources. Here, we aimed to identify enhancers in pancreatic islets, to understand their developmental ontologies, and to identify enhancers unique to islets to increase our understanding of islet-specific gene expression. METHODS: We combined H3K4me1-based nucleosome predictions with pancreatic and duodenal homeobox 1 (PDX1), neurogenic differentiation 1 (NEUROD1), v-Maf musculoaponeurotic fibrosarcoma oncogene family, protein A (MAFA) and forkhead box A2 (FOXA2) occupancy data to identify enhancers in mouse islets. RESULTS: We identified 22,223 putative enhancer loci in in vivo mouse islets. Our validation experiments suggest that nearly half of these loci are active in regulating islet gene expression, with the remaining regions probably poised for activity. We showed that these loci have at least nine developmental ontologies, and that islet enhancers predominately acquire H3K4me1 during differentiation. We next discriminated 1,799 enhancers unique to islets and showed that these islet-specific enhancers have reduced association with annotated genes, and identified a subset that are instead associated with novel islet-specific long non-coding RNAs (lncRNAs). CONCLUSIONS/INTERPRETATIONS: Our results indicate that genes with islet-specific expression and function tend to have enhancers devoid of histone methylation marks or, less often, that are bivalent or repressed, in embryonic stem cells and liver. Further, we identify a subset of enhancers unique to islets that are associated with novel islet-specific genes and lncRNAs. We anticipate that these data will facilitate the development of novel sources of functional beta cell mass.


Assuntos
Ilhotas Pancreáticas/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Imunoprecipitação da Cromatina , Elementos Facilitadores Genéticos/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo , Proteínas de Homeodomínio/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Transativadores/metabolismo
6.
Vet Comp Orthop Traumatol ; 25(2): 155-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22366963

RESUMO

Two kittens aged between four and five months were presented having sustained patellar fractures. In both cases, healing was subsequently documented radiographically; this has not been reported previously in the literature. One kitten had bilateral patellar fractures - the symptomatic right stifle was treated with a pin and tension-band-wire which later failed, at which point partial patellectomy was performed. The fracture of the left patella was minimally displaced and was treated conservatively. A radiograph of the left patella taken eleven months after initial presentation showed complete healing of the fracture. The second case was treated surgically with a circumferential wire; healing of the fracture was demonstrated radiographically at twelve weeks postoperatively. Radiographic images taken five weeks postoperatively had shown some narrowing of the fracture gap. These two cases demonstrate that bony union of patellar fractures can be documented, given a long enough duration of radiographic follow-up; circumferential wire was an effective treatment in a displaced fracture, and conservative treatment resulted in complete healing of a minimally displaced fracture.


Assuntos
Doenças do Gato/cirurgia , Fraturas Ósseas/veterinária , Patela/lesões , Animais , Gatos , Feminino , Fraturas Ósseas/patologia , Fraturas Ósseas/cirurgia , Coxeadura Animal , Masculino , Patela/patologia , Patela/cirurgia
7.
Clin Exp Immunol ; 161(2): 250-67, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20491795

RESUMO

Type 1 diabetes is an autoimmune disease whose clinical onset signifies a lifelong requirement for insulin therapy and increased risk of medical complications. To increase the efficiency and confidence with which drug candidates advance to human type 1 diabetes clinical trials, we have generated and validated a mathematical model of type 1 diabetes pathophysiology in a well-characterized animal model of spontaneous type 1 diabetes, the non-obese diabetic (NOD) mouse. The model is based on an extensive survey of the public literature and input from an independent scientific advisory board. It reproduces key disease features including activation and expansion of autoreactive lymphocytes in the pancreatic lymph nodes (PLNs), islet infiltration and beta cell loss leading to hyperglycaemia. The model uses ordinary differential and algebraic equations to represent the pancreas and PLN as well as dynamic interactions of multiple cell types (e.g. dendritic cells, macrophages, CD4+ T lymphocytes, CD8+ T lymphocytes, regulatory T cells, beta cells). The simulated features of untreated pathogenesis and disease outcomes for multiple interventions compare favourably with published experimental data. Thus, a mathematical model reproducing type 1 diabetes pathophysiology in the NOD mouse, validated based on accurate reproduction of results from multiple published interventions, is available for in silico hypothesis testing. Predictive biosimulation research evaluating therapeutic strategies and underlying biological mechanisms is intended to deprioritize hypotheses that impact disease outcome weakly and focus experimental research on hypotheses likely to provide insight into the disease and its treatment.


Assuntos
Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/fisiopatologia , Modelos Biológicos , Algoritmos , Animais , Simulação por Computador , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos NOD , Modelos Imunológicos , Pâncreas/imunologia , Pâncreas/fisiopatologia
8.
Clin Exp Immunol ; 147(2): 313-23, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17223973

RESUMO

Gut mesenchymal fibroblasts form complex phenotypical and functional populations. They participate actively in homeostatic maintenance of the extracellular matrix, epithelial barrier function, repair mechanisms and leucocyte migration. In inflammation, they become activated, change matrix expression and synthesize proinflammatory mediators. Subpopulations of mucosal fibroblasts express CD40 and the aim of this study was to define its role in their proinflammatory function. Stable primary fibroblast lines derived from normal mouse colon and inflamed colon from CD4(+) CD45RB(high)-transplanted SCID mice were used as models to explore the role of mucosal fibroblast CD40 in the inflammatory process. Phenotype correlated with in situ fibroblast phenotype in the tissues of origin. Lines from both sources co-expressed CD40 and Thy1.2 independently of alpha-smooth muscle actin. A subpopulation of CD40(+) fibroblasts from normal colon expressed CD40 at high levels and expression was enhanced by interferon (IFN)-gamma treatment, whereas all CD40(+) fibroblasts from colitis expressed at low levels and expression was unaffected by IFN-gamma treatment. Despite lower-level expression of CD40 by cells from colitis, they secreted constitutively interleukin (IL)-6 and C-C chemokine (CCL)2. Ligation of CD40 enhanced secretion of these mediators and induced secretion of CCL3. CD40 in cells from colitis was more responsive to ligation than CD40 on cells from normal tissue and this sensitivity was amplified selectively by the action of IFN-gamma. We conclude that the inflammatory milieu in colitis induces long-lasting changes in phenotype and proinflammatory function in colonic fibroblasts. In particular, proinflammatory signalling from fibroblast CD40 is amplified synergistically by the Th1 effector T cell cytokine, IFN-gamma.


Assuntos
Antígenos CD40/imunologia , Colite/imunologia , Citocinas/biossíntese , Fibroblastos/imunologia , Interferon gama/imunologia , Animais , Antígenos CD40/metabolismo , Ligante de CD40/imunologia , Linhagem Celular , Mediadores da Inflamação/imunologia , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Transdução de Sinais/imunologia , Regulação para Cima/imunologia
9.
Gut ; 54(8): 1114-20, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16009684

RESUMO

INTRODUCTION: Exacerbations of inflammatory bowel disease are thought to be related to concurrent infections. As infections are associated with elevated local and serum concentrations of chemokines, we have determined whether systemic administration of the CC chemokine macrophage inflammatory protein 1alpha (MIP-1alpha) exacerbates colitis in a mouse model. METHODS: Colitis was induced in Balb/c mice using trinitrobenzene sulfonic acid (TNBS). Starting four days later, animals received daily intraperitoneal injections of recombinant MIP-1alpha. On day 7, mice were killed and pieces of colon taken for immunohistology and polymerase chain reaction analysis. The direct effects of MIP-1alpha on mucosal T cells and fibroblasts in vitro were also investigated. RESULTS: Systemic administration of MIP-1alpha markedly enhanced colitis with mice developing large transmural ulcers filled with granulation tissue. Treatment resulted in increased numbers of CD4 cells infiltrating the colonic lamina propria, increased interferon gamma (IFN-gamma) levels, and increased transcripts for tumour necrosis factor alpha (TNF-alpha) and matrix metalloproteinase 3 (MMP3). Isolated lamina propria lymphocytes from mice with TNBS colitis contained increased numbers of IFN-gamma and TNF-alpha transcripts when stimulated with MIP-1alpha in vitro. Colonic lamina propria fibroblasts also responded to MIP-1alpha with increased proliferation and decreased collagen 1 synthesis but fibroblast proliferation was not seen in vivo. CONCLUSIONS: These experiments show that increasing serum concentrations of a chemokine, MIP-1alpha, exacerbates immune mediated colitis. The effect seems to be due to the ability of MIP-1alpha to boost Th1 responses in the gut wall. Our findings also suggest a potential pathway by which peripheral infections can exacerbate inflammatory bowel disease.


Assuntos
Colite Ulcerativa/imunologia , Proteínas Inflamatórias de Macrófagos/administração & dosagem , Animais , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Quimiocina CCL3 , Quimiocina CCL4 , Colo/imunologia , Modelos Animais de Doenças , Feminino , Fibroblastos/imunologia , Imuno-Histoquímica/métodos , Injeções Intraperitoneais , Interferon gama/análise , Mucosa Intestinal/imunologia , Metaloproteinase 3 da Matriz/análise , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/análise
10.
J Histochem Cytochem ; 49(6): 727-38, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11373319

RESUMO

Using a CD4+ T-cell-transplanted SCID mouse model of colitis, we have analyzed TGF-beta transcription and translation in advanced disease. By in situ hybridization, the epithelium of both control and inflamed tissues transcribed TGF-beta1 and TGF-beta3 mRNAs, but both were expressed significantly farther along the crypt axis in disease. Control lamina propria cells transcribed little TGF-beta1 or TGF-beta3 mRNA, but in inflamed tissues many cells expressed mRNA for both isoforms. No TGF-beta2 message was detected in either control or inflamed tissues. Immunohistochemistry for latent and active TGF-beta1 showed that all cells produced perinuclear latent TGF-beta1. The epithelial cell basal latent protein resulted in only low levels of subepithelial active protein, which co-localized with collagen IV and laminin in diseased and control tissue. Infiltrating cells expressed very low levels of active TGF-beta. By ELISA, very low levels (0-69 pg/mg) of soluble total or active TGF-beta were detected in hypotonic tissue lysates. TGF-beta1 and TGF-beta3 are produced by SCID mouse colon and transcription is increased in the colitis caused by transplantation of CD4+ T-cells, but this does not result in high levels of soluble active protein. Low levels of active TGF-beta may be a factor contributing to unresolved inflammation.


Assuntos
Colite/imunologia , Doenças Inflamatórias Intestinais/imunologia , Fator de Crescimento Transformador beta/biossíntese , Animais , Linfócitos T CD4-Positivos/transplante , Colite/etiologia , Colite/genética , Colite/patologia , Colo/patologia , Tecido Conjuntivo/patologia , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Imuno-Histoquímica , Hibridização In Situ , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos SCID , RNA Mensageiro/isolamento & purificação , Distribuição Tecidual , Fator de Crescimento Transformador beta/genética
11.
Phys Occup Ther Pediatr ; 21(2-3): 81-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12029857

RESUMO

Research has shown that children who have experienced maltreatment are at increased risk of negative developmental outcomes, including difficulties with development of secure attachment relationships and effective peer relationships. However, until recently, few studies have examined the effects of maltreatment on the school performance of children in elementary school through high school. This review highlights published studies that shed light on this question. The need for further research and intervention on the part of occupational therapies who work in school systems is discussed.


Assuntos
Maus-Tratos Infantis , Avaliação Educacional , Estudantes , Criança , Maus-Tratos Infantis/reabilitação , Desenvolvimento Infantil , Humanos , Terapia Ocupacional
12.
Am J Pathol ; 157(6): 1927-35, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11106565

RESUMO

Proteinases are important at several phases of physiological and pathological inflammation, mediating cellular infiltration, cytokine activation, tissue damage, remodeling, and repair. However, little is known of their role in the pathogenesis of inflammatory bowel disease. The aim of this study was to assess the role of tissue proteases in a mouse model of colitis. Proteolytic activity was analyzed, using gel and in situ zymography, in colonic tissues from severe combined immunodeficient mice with colitis induced by transfer of CD4(+) T lymphocytes. Serine proteinase levels increased in colitic tissue, with major species of 23 kd, 30 kd, and 45 kd. Co-migration and inhibition studies indicated that the 23-kd proteinase was pancreatic trypsin and that the 30-kd species was neutrophil elastase. Matrix metalloproteinase (MMP)-9 expression, and MMP-2 and MMP-9 activation, was elevated in colitic tissues. Proteinase levels followed a decreasing concentration gradient from proximal to distal colon. Proteolysis was localized to infiltrating leukocytes in diseased severe combined immunodeficient mice. Transmural inflammation was associated with serine proteinase and MMP activity in overlying epithelium and with marked subepithelial proteolytic activity. The results demonstrate a clear elevation in the levels and activation of proteases in colitis, potentially contributing to disease progression through loss of epithelial barrier function.


Assuntos
Colite/etiologia , Metaloproteinases da Matriz/metabolismo , Serina Endopeptidases/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Movimento Celular/fisiologia , Colite/enzimologia , Colite/imunologia , Colite/fisiopatologia , Colo/enzimologia , Modelos Animais de Doenças , Endopeptidases/fisiologia , Ativação Enzimática/fisiologia , Epitélio/metabolismo , Matriz Extracelular/metabolismo , Fezes/enzimologia , Mucosa Intestinal/metabolismo , Leucócitos/fisiologia , Camundongos , Camundongos Endogâmicos , Camundongos SCID , Índice de Gravidade de Doença , Regulação para Cima
13.
Vaccine ; 18(28): 3254-65, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10869770

RESUMO

Feline immunodeficiency virus (FIV) is a natural lentiviral pathogen of cats which can be experimentally transmitted via rectal and vaginal routes--the major routes of human immunodeficiency virus type 1 transmission in man. An important objective for lentiviral research is the development of vaccine strategies which generate good mucosal immune responses capable of giving protection from a mucosal virus challenge. The experimental vaccines employed in this study were based on (a) a peptide from the third variable region of the FIV envelope glycoprotein and (b) fixed whole FIV, Glasgow-8 strain. Adjuvants used were Quil A and cholera toxin for mucosal administration and incomplete Freund's adjuvant and immune stimulating complexes for subcutaneous injection. Mucosal immunization was given by rectal and intranasal routes. Both antibody and proliferative responses were elicited by mucosal immunization and cholera toxin was found to be a good mucosal adjuvant. The addition of a lipo thioester to the FIV peptide improved IgG and IgA responses upon parenteral administration. However, no protection from a rectal FIV challenge was achieved.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Imunodeficiência Felina/imunologia , Ativação Linfocitária , Reto/virologia , Vacinas Virais/imunologia , Administração Intranasal , Administração Retal , Sequência de Aminoácidos , Animais , Gatos , Imunização , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Dados de Sequência Molecular , Linfócitos T/imunologia , Vacinas Virais/administração & dosagem
14.
Clin Exp Immunol ; 116(3): 415-24, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10361228

RESUMO

The adoptive transfer of activated CD4+ alpha/beta T cell blasts from the spleens of immunocompetent C.B-17+/+ or BALB/cdm2 mice into C.B-17scid/scid (scid) mice induces a colitis in the scid recipient within 8 weeks, which progresses to severe disease within 16 weeks. T cells isolated from recipient colon show a Th1 cytokine phenotype. We have examined the relationship between the phenotype of the cellular infiltrate and the transcription and translation of the proinflammatory cytokine TNF-alpha. The techniques of double indirect immunohistology and in situ hybridization using digoxigenin-labelled riboprobes were used. The prominent myeloid cell infiltrate in diseased tissues comprised F4/80+, Mac-l+ macrophages, neutrophils, dendritic cells and activated macrophages. TNF-alpha transcription and translation were associated with activated macrophages in the lamina propria. Activated macrophages transcribing and translating TNF-alpha were clustered in areas of tissue destruction. Crypt epithelium of inflamed tissues transcribed TNF-alpha at a very early stage of the disease process, but translation of TNF-alpha protein could only be found in advanced epithelial dysplasia. This indicates differential post-transcriptional control of TNF-alpha in activated macrophages and the epithelium.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Colite/genética , Colite/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Transferência Adotiva , Animais , Colite/etiologia , Modelos Animais de Doenças , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica
15.
Vet Pathol ; 33(6): 699-703, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8952030

RESUMO

This report describes the clinical, pathological, immunocytochemical, and in situ hybridization characteristics of encephalitis associated with feline immunodeficiency virus (FIV) infection in a 4-year-old domestic cat. Lesions were identified throughout the brain, affecting the cerebrum, medulla, and cervical spinal cord. Perivascular lymphocytic cuffing, gliosis, and white matter vacuolation were most severe in the cerebrum, affecting the white matter and the deep laminae of the grey matter. Gemistocytes were prominent, and many bizarre cells with large, sometimes multinucleate, hyperchromatic nuclei were evident. Immunostaining with antibody specific for FIV p24 nucleocapsid protein produced staining in the gemistocytes and glial cells of the white matter. In situ hybridization with a 327-base pair fragment of the FIV gag gene produced staining that was most intense in the white matter and gemistocytes of the deep laminae of the grey matter. These findings indicated localization of FIV infection within the cerebrum, and the detection of FIV RNA by in situ hybridization confirms the infection as active.


Assuntos
Doenças do Gato/patologia , Encefalite/veterinária , Síndrome de Imunodeficiência Adquirida Felina/patologia , Células Gigantes/patologia , Vírus da Imunodeficiência Felina/isolamento & purificação , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Sequência de Bases , Encéfalo/imunologia , Encéfalo/patologia , Encéfalo/virologia , Química Encefálica , Doenças do Gato/diagnóstico , Gatos , DNA Viral/análise , DNA Viral/genética , Encefalite/complicações , Encefalite/patologia , Síndrome de Imunodeficiência Adquirida Felina/complicações , Síndrome de Imunodeficiência Adquirida Felina/diagnóstico , Células Gigantes/química , Vírus da Imunodeficiência Felina/genética , Imuno-Histoquímica , Hibridização In Situ/métodos , Hibridização In Situ/veterinária , Masculino , Nucleocapsídeo/imunologia , RNA Viral/análise , RNA Viral/genética
16.
Vaccine ; 14(13): 1243-50, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8961513

RESUMO

Infection of cats with feline immunodeficiency virus (FIV), a naturally occurring lentivirus infection of cats which causes an AIDS-like disease, has generated considerable interest as an animal model for HIV vaccination. This paper reports on experiments performed to examine the potential of a fixed infected cell vaccine to confer protection against intraperitoneal challenge with cell-free FIV. The cell vaccine was highly immunogenic and elicited antibody responses to virus core antigen, p24, high virus neutralizing (VN) antibody titres, and antibodies which recognized cellular components of the vaccine. Whilst protection, assessed by the inability to detect infectious virus by virus isolation or polymerase chain reaction, against homologous but not heterologous FIV isolates was apparent up to week 12 post-challenge, when cats were monitored longer up to week 50 post-challenge a breakthrough in vaccine protection against homologous virus was observed. Protection could not be correlated with levels of antibody to p24 or VN antibody titres. In contrast with simian immunodeficiency virus vaccine studies in macaques there was no clear evidence that antibodies recognizing cellular components of the vaccine, including MHC class I and II antigens, conferred any protective effect following challenge. These results indicate that long-term post-challenge monitoring for infection is essential in lentivirus vaccine trials.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/prevenção & controle , Vírus da Imunodeficiência Felina/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Gatos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Immunoblotting , Vacinação
17.
Vet Microbiol ; 51(3-4): 217-27, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8870185

RESUMO

The objective of this study was to examine the potential of vaginal and rectal mucosal routes for feline immunodeficiency virus (FIV) uptake and infection, as a model of mucosal HIV infection, and to determine the fate of virus at these mucosal sites following transmission of infection. SPF cats were exposed to FIV isolates (PET, GL-8, T637), administered as either cell-associated or cell-free inocula, via the rectum or vagina. Establishment of infection was confirmed by isolation of infectious FIV from peripheral blood mononuclear cells (PBMC), and by presence of FIV proviral DNA in PBMC using a nested polymerase chain reaction. Fate of virus in tissue taken at necropsy from cats infected for 6-48 weeks was assessed by localizing FIV core and envelope proteins, p24 and gp41, using a biotin-streptavidin linked immunoperoxidase (IP) technique. Cells susceptible to infection were identified by an in situ hybridization technique for FIV viral DNA and RNA. Cell-free, as well as cell-associated, virus was infectious across intact vaginal and rectal mucosal surfaces. Transmission was most successful using cell-associated inocula, and via the rectal route. Cells infected with FIV were detected by IP staining in the colon of 6/9 rectally challenged cats and 1/5 vaginally challenged cats. Virus was predominantly localized within the epithelium at the base of the colonic crypts associated with lymphoid aggregates (follicle associated epithelium; FAE), and within the lymphoid follicle itself. Occasional infected cells were also noted within the lamina propria. The distribution of FIV DNA positive cells in the colon was similar to that for FIV antigen whilst FIV RNA positive cells were found more extensively, including within the lamina propria and lymphoid follicle. FIV infected cells were not detected within the vagina, or colonic and ileac lymph nodes. Similar patterns of infected cells were seen in all of the positive cats, indicating that colonic tissues remain persistently actively infected with FIV. We conclude that the FIV/cat model of rectal and vaginal mucosal infection should prove useful for characterizing the mechanism by which HIV infects mucosal surfaces and as a challenge system for the design of vaccines effective at preventing HIV infection via rectal and vaginal routes.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/patologia , Vírus da Imunodeficiência Felina/isolamento & purificação , Vírus da Imunodeficiência Felina/patogenicidade , Mucosa Intestinal/patologia , Vagina/virologia , Animais , Gatos , Primers do DNA , DNA Viral/análise , Síndrome de Imunodeficiência Adquirida Felina/virologia , Feminino , Hibridização In Situ , Mucosa Intestinal/virologia , Tecido Linfoide/patologia , Tecido Linfoide/virologia , Masculino , Mucosa/patologia , Mucosa/virologia , Reação em Cadeia da Polimerase/métodos , Reto , Sequências Repetitivas de Ácido Nucleico , Vagina/patologia
18.
Immunology ; 79(1): 107-11, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8509132

RESUMO

In the gut, both the villus epithelium and cells of macrophages and dendritic cell lineages of the lamina propria and Peyer's patches express major histocompatibility complex (MHC) class II glycoproteins and have the potential to present soluble protein antigen. Using mice transgenic for the X and Y promoter deletion mutants of the gene encoding the I-Ek alpha class II protein we have shown: that an intact promoter is essential for expression of I-Ek alpha on the epithelium and lamina propria macrophages; that only the Y box is essential for expression by lamina propria dendritic cells; and that dendritic cells in Peyer's patches are phenotypically more restricted than in the lamina propria and express I-Ek alpha under different regulatory control mechanisms. The results show that different inductive mechanisms exist for class II in distinct mucosal cell populations and provide a model for the analysis of differential antigen handling in the gut mucosa.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Regulação da Expressão Gênica/imunologia , Genes MHC da Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Intestino Delgado/imunologia , Animais , Células Dendríticas/imunologia , Epitélio/imunologia , Técnicas Imunoenzimáticas , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Nódulos Linfáticos Agregados/imunologia
19.
Immunology ; 75(2): 366-71, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1551699

RESUMO

The induction of major histocompatibility complex (MHC) class II expression in the epithelium of the small intestine of the rat during graft-versus-host disease (GVHD) and the effect of this process on the capacity of isolated epithelial cells to present antigen has been investigated. By immunohistology, increased class II (I-A) was noted in lamina propria cells and villus epithelium and de novo expression in crypt epithelium by Day 7 after transfer of parental spleen cells into irradiated hybrid rats. This increased expression reached a maximum by Day 9 or 10. The kinetics of induction of I-E products paralleled those of I-A in villus epithelium, but I-E was not seen in crypt epithelium. Direct radioimmunoassay of class II in isolated villus and crypt epithelial cells revealed a minor peak of class II, particularly in villus cells, very soon after cell transfer which waned and then increased to a second peak at Days 7-9. Assay of presentation of ovalbumin by isolated enterocytes to primed T cells at the peak of class II induction showed that increased class II expression by villus cells mediated enhanced antigen-presenting activity, whereas increases in crypt cell class II did not enable these cells to present ovalbumin.


Assuntos
Expressão Gênica/imunologia , Genes MHC da Classe II/imunologia , Doença Enxerto-Hospedeiro/imunologia , Intestino Delgado/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Divisão Celular/imunologia , Epitélio/imunologia , Feminino , Cinética , Masculino , Ratos , Ratos Endogâmicos , Linfócitos T/imunologia
20.
Yale J Biol Med ; 63(6): 549-56, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2092413

RESUMO

This study was undertaken to determine if the observed increase in ventilation during passive limb movement was a reflex hyperventilation or a response to an increased metabolic need for oxygen. Experiments on human volunteers were designed to test the hypothesis that the rapid increase of ventilation at the onset of exercise was due to stimulation of the joints. Results of these studies showed significant increases in ventilation, oxygen consumption, carbon dioxide production, ventilation/oxygen consumption ratio, and heart rate compared to rest and recovery values. The data lead to the conclusion that the rapid increase of ventilation at the onset of exercise is a true hyperventilation and that stimulation of the joints can be a significant contributor to increased pulmonary ventilation.


Assuntos
Exercício Físico/fisiologia , Mecânica Respiratória/fisiologia , Adulto , Extremidades/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Hiperventilação/fisiopatologia , Masculino , Mecanorreceptores/fisiologia , Movimento/fisiologia , Consumo de Oxigênio/fisiologia , Reflexo/fisiologia
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