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1.
Perspect Public Health ; 141(6): 328-337, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34816775

RESUMO

AIMS: There are a growing number of organisations working to address the connections between climate change and health. This article introduces the concept of 'theories of change' - the methodology by which organisations or movements hope to bring about social change - and applies it to the current climate change and health movement in England. Through movement mapping, the article describes and offers reflections on the climate change and health ecosystems in England. METHODS: Organisations working on climate change and health in England were identified and publicly available information was collated to map movement characteristics, target stakeholders and methodologies deployed, using an inductive, iterative approach. RESULTS: A total of 98 organisations working on health and climate change (and/or sustainability) were initially identified, of which 70 met the inclusion criteria. Most organisations target two or more stakeholders, with healthcare workers, management structures, and government being most commonly cited. Methodological approaches identified include Formal education programmes; Awareness-raising; Purchasing-procurement power; Advocacy; Financial; Media-messaging; Networking; Knowledge generation; and Policy making, of which education, awareness-raising, and advocacy are most commonly used. CONCLUSION: There is a tendency for climate change and health organisations in England to focus on individual level and sectoral change over system change. More could be made of the potential for the healthcare professions' voice and messaging for the wider climate movement. Given the rapid boom of climate change and health organisations in recent years, a mind-set shift that recognises different players as part of a cohesive ecosystem with better coordination and collaboration may reduce unnecessary work, and facilitate more cohesive outcomes.


Assuntos
Mudança Climática , Ecossistema , Inglaterra , Pessoal de Saúde , Humanos
2.
Brain Lang ; 145-146: 34-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25950747

RESUMO

The developmental trajectory of language lateralisation over the preschool years is unclear. We explored the relationship between lateralisation of cerebral blood flow velocity response to object naming and cognitive performance in children aged 1-5 years. Functional transcranial Doppler ultrasound was used to record blood flow velocity bilaterally from middle cerebral arteries during a naming task in 58 children (59% male). At group level, the Lateralisation Index (LI) revealed a greater relative increase in cerebral blood flow velocity within the left as compared to right middle cerebral artery. After controlling for maternal IQ, left-lateralised children displayed lower expressive language scores compared to right- and bi-lateralised children, and reduced variability in LI. Supporting this, greater variability in lateralised response, rather than mean response, was indicative of greater expressive language ability. Findings suggest that a delayed establishment of language specialisation is associated with better language ability in the preschool years.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Lateralidade Funcional/fisiologia , Desenvolvimento da Linguagem , Idioma , Encéfalo/irrigação sanguínea , Criança , Pré-Escolar , Feminino , Hemodinâmica/fisiologia , Humanos , Lactente , Masculino , Estimulação Luminosa/métodos , Ultrassonografia Doppler Transcraniana/métodos
3.
Diabet Med ; 32(7): 899-906, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25594919

RESUMO

BACKGROUND: Adding pharmacists to primary care teams significantly improved blood pressure control and reduced predicted 10-year cardiovascular risk in patients with Type 2 diabetes. This pre-specified sub-study evaluated the economic implications of this cardiovascular risk reduction strategy. METHODS: One-year outcomes and healthcare utilization data from the trial were used to determine cost-effectiveness from the public payer perspective. Costs were expressed in 2014 Canadian dollars and effectiveness was based on annualized risk of cardiovascular events derived from the UKPDS Risk Engine. RESULTS: The 123 evaluable trial patients included in this analysis had a mean age of 62 ( ± 11) years, 38% were men, and mean diabetes duration was 6 ( ± 7) years. Pharmacists provided 3.0 ( ± 1.9) hours of additional service to each intervention patient, which cost $226 ( ± $1143) per patient. The overall one-year per-patient costs for healthcare utilization were $190 lower in the intervention group compared with usual care [95% confidence interval (CI): -$1040, $668). Intervention patients had a significant 0.3% greater reduction in the annualized risk of a cardiovascular event (95% CI: 0.08%, 0.6%) compared with usual care. In the cost-effectiveness analysis, the intervention dominated usual care in 66% of 10,000 bootstrap replications. At a societal willingness-to-pay of $4000 per 1% reduction in annual cardiovascular risk, the probability that the intervention was cost-effective compared with usual care reached 95%. A sensitivity analysis using multiple imputation to replace missing data produced similar results. CONCLUSIONS: Within a randomized trial, adding pharmacists to primary care teams was a cost-effective strategy for reducing cardiovascular risk in patients with Type 2 diabetes. In most circumstances, this intervention may also be cost saving.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/economia , Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Equipe de Assistência ao Paciente , Farmacêuticos , Idoso , Canadá/epidemiologia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/terapia , Terapia Combinada/economia , Análise Custo-Benefício , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/economia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/terapia , Cardiomiopatias Diabéticas/economia , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/terapia , Monitoramento de Medicamentos/economia , Feminino , Seguimentos , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Equipe de Assistência ao Paciente/economia , Farmacêuticos/economia , Atenção Primária à Saúde , Fatores de Risco
4.
Mol Oral Microbiol ; 29(2): 67-78, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24517244

RESUMO

Extracellular signaling during inflammation and chronic diseases involves molecules referred to as 'Danger Signals' (DS), including the small molecule adenosine. We demonstrate that primary gingival epithelial cells (GEC) express a family of G-protein coupled receptors known as adenosine receptors, including the high-affinity receptors A1 and A2a and low-affinity receptors A2b and A3. Treatment of Porphyromonas gingivalis-infected GEC with the A2a receptor-specific agonist CGS-21680 resulted in elevated intracellular bacterial replication as determined by fluorescence microscopy and antibiotic protection assay. Additionally, A2a receptor antagonism and knockdown via RNA interference significantly reduced metabolically active intracellular P. gingivalis. Furthermore, analysis of anti-inflammatory mediator cyclic AMP (cAMP) following A2a receptor selective agonist CGS-21680 stimulation induced significantly higher levels of cAMP during P. gingivalis infection, indicating that adenosine signaling may attenuate inflammatory processes associated with bacterial infection. This study reveals that the GEC express functional A2a receptor and P. gingivalis may use the A2a receptor coupled DS adenosine signaling as a means to establish successful persistence in the oral mucosa, possibly via downregulation of the pro-inflammatory response.


Assuntos
Adenosina/metabolismo , Gengiva/metabolismo , Porphyromonas gingivalis/crescimento & desenvolvimento , Receptor A2A de Adenosina/metabolismo , Transdução de Sinais , Células Cultivadas , AMP Cíclico/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Gengiva/citologia , Humanos
6.
Vet Rec ; 170(26): 673, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22562099

RESUMO

Orf, a viral disease which causes proliferative skin lesions around the mouths of lambs and on the teats of ewes, has long been assumed to have production-limiting consequences. This case-control study involved the collection of data from naturally occurring outbreaks of orf in young lambs on eight commercial farms in north-east England. Measurements of weight were taken and orf lesions were scored on a numerical scale for 44 orf-affected lambs, matched to unaffected controls within the same group. Data from corresponding ewes were available from five farms. Paired t tests showed that affected lambs weighed approximately 10 per cent less than their unaffected controls for a period of at least five weeks following the start of the outbreak. The effects were highly significant whether the orf lesions affected the mouth or were found elsewhere on the body. If a lamb had orf, then there was a 82 per cent chance that its mother also had orf on its udder or teats. The financial consequences of orf in young lambs were estimated using average UK figures and conservative assumptions based on the results of this study.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Surtos de Doenças/veterinária , Ectima Contagioso/economia , Aumento de Peso , Animais , Estudos de Casos e Controles , Custos e Análise de Custo , Surtos de Doenças/economia , Ectima Contagioso/epidemiologia , Feminino , Masculino , Ovinos , Reino Unido , Desmame
7.
Diabet Med ; 29(11): 1433-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22486226

RESUMO

AIM: To determine the impact of adding pharmacists to primary care teams on predicted 10-year risk of cardiovascular events in patients with Type 2 diabetes without established cardiovascular disease. METHODS: This was a pre-specified secondary analysis of randomized trial data. The main study found that, compared with usual care, addition of a pharmacist resulted in improvements in blood pressure, dyslipidaemia, and hyperglycaemia for primary care patients with Type 2 diabetes. In this sub-study, predicted 10-year risk of cardiovascular events at baseline and 1 year were calculated for patients free of cardiovascular disease at enrolment. The primary outcome was change in UK Prospective Diabetes Study (UKPDS) risk score; change in Framingham risk score was a secondary outcome. RESULTS: Baseline characteristics were similar between the 102 intervention patients and 93 control subjects: 59% women, median (interquartile range) age 57 (50-64) years, diabetes duration 3 (1-6.5) years, systolic blood pressure 128 (120-140) mmHg, total cholesterol 4.34 (3.75-5.04) mmol/l and HbA(1c) 54 mmol/mol (48-64 mmol/mol) [7.1% (6.5-8.0%)]. Median baseline UKPDS risk score was 10.2% (6.0-16.7%) for intervention patients and 9.5% (5.8-15.1%) for control subjects (P = 0.80). One-year post-randomization, the median absolute reduction in UKPDS risk score was 1.0% greater for intervention patients compared with control subjects (P = 0.032). Similar changes were seen with the Framingham risk score (median reduction 1.2% greater for intervention patients compared with control subjects, P = 0.048). The two risk scores were highly correlated (rho = 0.83; P < 0.001). CONCLUSION: Adding pharmacists to primary care teams for 1 year significantly reduced the predicted 10-year risk of cardiovascular events for patients with Type 2 diabetes without established cardiovascular disease.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Dislipidemias/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Equipe de Assistência ao Paciente , Farmacêuticos , Atenção Primária à Saúde/organização & administração , Adulto , Idoso , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/fisiopatologia , Análise Custo-Benefício , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Angiopatias Diabéticas/prevenção & controle , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hipoglicemiantes/administração & dosagem , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/organização & administração , Estudos Prospectivos , Fatores de Risco
9.
Aliment Pharmacol Ther ; 25(9): 1069-77, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17439508

RESUMO

BACKGROUND: Myelosuppression occurs in 2-7% of inflammatory bowel disease (IBD) patients treated with azathioprine, and can be associated with reduced activity of thiopurine methyltransferase (TPMT) in some patients. It has been proposed that pretreatment assessment of TPMT status reduces the incidence of toxicity and is cost-effective. AIMS: To determine if screening for TPMT status predicts side-effects to azathioprine in patients with IBD and to ascertain whether screening by TPMT enzyme activity or genotype is superior. METHODS: Sequential IBD patients were identified and azathioprine tolerance recorded. Blood was collected for measurement of TPMT activity and TPMT*3C, TPMT*3A and TPMT*2 genotypes. RESULTS: Of 130 patients, 25% stopped azathioprine because of toxicity. Four patients experienced severe myelosuppression (WCC < 2). Eleven of 17 patients with reduced TPMT activity were heterozygotes, including one patient with marked TPMT deficiency who experienced severe myelosuppression. There was no association between intermediate TPMT deficiency and any side-effect. CONCLUSIONS: Moderate reduction of TPMT activity in heterozygotes was not associated with toxicity, but very low TPMT activity caused severe myelosuppression in one patient. This would have been predicted by measuring TPMT activity but not by genotyping. Measurement of TPMT activity may therefore be superior to genotype in predicting severe myelosuppression.


Assuntos
Fármacos Gastrointestinais/efeitos adversos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Linfopenia/induzido quimicamente , Mercaptopurina/análogos & derivados , Metiltransferases/metabolismo , Ensaios Enzimáticos Clínicos/economia , Ensaios Enzimáticos Clínicos/métodos , Análise Custo-Benefício , Feminino , Técnicas Genéticas/economia , Genótipo , Humanos , Doenças Inflamatórias Intestinais/economia , Doenças Inflamatórias Intestinais/enzimologia , Linfopenia/economia , Masculino , Espectrometria de Massas/economia , Espectrometria de Massas/métodos , Mercaptopurina/efeitos adversos , Reação em Cadeia da Polimerase/economia , Sensibilidade e Especificidade
10.
Biochemistry ; 46(15): 4606-18, 2007 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-17385891

RESUMO

The function of the stacking tryptophan, W290, a second-coordination sphere residue in galactose oxidase, has been investigated via steady-state kinetics measurements, absorption, CD and EPR spectroscopy, and X-ray crystallography of the W290F, W290G, and W290H variants. Enzymatic turnover is significantly slower in the W290 variants. The Km for D-galactose for W290H is similar to that of the wild type, whereas the Km is greatly elevated in W290G and W290F, suggesting a role for W290 in substrate binding and/or positioning via the NH group of the indole ring. Hydrogen bonding between W290 and azide in the wild type-azide crystal structure are consistent with this function. W290 modulates the properties and reactivity of the redox-active tyrosine radical; the Y272 tyrosyl radicals in both the W290G and W290H variants have elevated redox potentials and are highly unstable compared to the radical in W290F, which has properties similar to those of the wild-type tyrosyl radical. W290 restricts the accessibility of the Y272 radical site to solvent. Crystal structures show that Y272 is significantly more solvent exposed in the W290G variant but that W290F limits solvent access comparable to the wild-type indole side chain. Spectroscopic studies indicate that the Cu(II) ground states in the semireduced W290 variants are very similar to that of the wild-type protein. In addition, the electronic structures of W290X-azide complexes are also closely similar to the wild-type electronic structure. Azide binding and azide-mediated proton uptake by Y495 are perturbed in the variants, indicating that tryptophan also modulates the function of the catalytic base (Y495) in the wild-type enzyme. Thus, W290 plays multiple critical roles in enzyme catalysis, affecting substrate binding, the tyrosyl radical redox potential and stability, and the axial tyrosine function.


Assuntos
Radicais Livres/metabolismo , Galactose Oxidase/metabolismo , Triptofano/metabolismo , Tirosina/metabolismo , Sítios de Ligação/genética , Catálise , Cristalografia por Raios X , Radicais Livres/química , Galactose/metabolismo , Galactose Oxidase/química , Galactose Oxidase/genética , Cinética , Estrutura Molecular , Mutação , Oxirredução , Estrutura Secundária de Proteína , Espectrofotometria Atômica , Especificidade por Substrato , Triptofano/química , Triptofano/genética , Tirosina/química
11.
Aliment Pharmacol Ther ; 20(6): 593-9, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15352906

RESUMO

BACKGROUND: Azathioprine is a useful agent in the management of inflammatory bowel disease. Its use is limited by its side-effect profile. Marrow toxicity occurs in approximately 3.2% of patients and is known to be associated with diminished thiopurine methyltransferase enzyme activity resulting from genetic polymorphisms. AIM: To evaluate the cost-effectiveness of screening for thiopurine methyltransferase gene polymorphisms prior to initiation of azathioprine therapy. METHODS: Analysis of the literature was undertaken to calculate the expected frequency of leucopenia and its relationship with thiopurine methyltransferase polymorphisms in a model of theoretical inflammatory bowel disease patients. Decision analysis was then applied to assess the cost of a pre-treatment genotyping strategy, taking account of direct costs and cost per life-year saved. RESULTS: In 1000 inflammatory bowel disease patients treated with azathioprine, 32 will develop myelosuppression and one will die because of this. Of those who develop myelosuppression during azathioprine therapy, 32% are attributable to lower thiopurine methyltransferase activity. Pre-treatment genotyping costs pound 347 per life-year saved for a 30 year old and pound 817 per life-year saved for a 60 year old. This compares favourably with other health care technologies. CONCLUSION: The use of pre-treatment screening for thiopurine methyltransferase polymorphisms in inflammatory bowel disease patients commencing azathioprine therapy represents good value for money.


Assuntos
Azatioprina/uso terapêutico , Testes Genéticos/economia , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/genética , Metiltransferases/genética , Polimorfismo Genético/genética , Adulto , Azatioprina/economia , Redução de Custos , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Testes Genéticos/métodos , Genótipo , Heterozigoto , Homozigoto , Humanos , Imunossupressores/economia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/economia , Pessoa de Meia-Idade
12.
Chembiochem ; 5(7): 972-9, 2004 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-15239055

RESUMO

Galactose oxidase (GO; EC 1.1.3.9) catalyses the oxidation of a wide range of primary alcohols including mono-, oligo- and polysaccharides. High-resolution structures have been determined for GO, but no structural information is available for the enzyme with bound substrate or inhibitor. Previously, computer-aided docking experiments have been used to develop a plausible model for interactions between GO and the D-galactose substrate. Residues implicated in such interactions include Arg330, Gln406, Phe464, Phe194 and Trp290. In the present study we describe an improved expression system for recombinant GO in the methylotrophic yeast Pichia pastoris. We use this system to express variant proteins mutated at Arg330 and Phe464 to explore the substrate binding model. We also demonstrate that the Arg330 variants display greater fructose oxidase activity than does wild-type GO.


Assuntos
Frutose/metabolismo , Galactose Oxidase/metabolismo , Galactose/metabolismo , Mutação , Pichia/genética , Cristalografia por Raios X , Galactose Oxidase/química , Galactose Oxidase/genética , Oxirredução , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato , Transformação Genética
13.
J Thromb Haemost ; 2(7): 1047-54, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15219185

RESUMO

BACKGROUND: Previous studies of the development of inhibitors and their impact on mortality have been small. OBJECTIVES: To examine the development of inhibitors in people with hemophilia in the UK and their effect on subsequent mortality. PATIENTS: 6078 males with hemophilia A and 1172 males with hemophilia B registered in the UK Haemophilia Centre Doctors' Organisation database, 1977-98. RESULTS: In severe hemophilia A inhibitors developed at rates of 34.4, 5.2 and 3.8 per 1000 years at ages <5, 5-14 and 15+years; cumulative risks at ages 5 and 75 were 16% and 36%. In hemophilia A the rate of inhibitor development decreased during 1977-90, but increased during the 1990s. In severe hemophilia B inhibitors developed at rates of 13.3 and 0.2 per 1000 years at ages <5 and 5+ and cumulative risks at ages 5 and 75 were 6% and 8%. With HIV, inhibitor development did not increase mortality. In severe hemophilia without HIV, inhibitor development doubled mortality during 1977-92, but during 1993-99 mortality was identical with and without inhibitors. In severe hemophilia without HIV but with inhibitors, mortality from causes involving bleeding decreased during 1977-99 (P = 0.001) as did mortality involving intracranial hemorrhage (P = 0.007). CONCLUSIONS: These data provide estimates of the rate of inhibitor development in hemophilia A and hemophilia B, and they show that the rate of inhibitor development has varied over time, although the reasons for this remain unclear. They also show that in severe hemophilia the substantial increase in mortality previously associated with inhibitors is no longer present.


Assuntos
Hemofilia A/imunologia , Hemofilia B/imunologia , Isoanticorpos/sangue , Adolescente , Criança , Pré-Escolar , Bases de Dados como Assunto , Fator IX/imunologia , Fator VIII/imunologia , Infecções por HIV/mortalidade , Hemofilia A/epidemiologia , Hemofilia A/mortalidade , Hemofilia B/epidemiologia , Hemofilia B/mortalidade , Humanos , Incidência , Estudos Longitudinais , Masculino , Risco , Taxa de Sobrevida , Fatores de Tempo , Reino Unido
14.
J Clin Pathol ; 57(4): 439-41, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047754

RESUMO

Hereditary haemochromatosis is the most common inherited disorder in white populations, whereas non-alcoholic steatohepatitis (NASH) is becoming the most common reason for referral for investigation of abnormal liver function tests (LFTs). This report describes two sisters, from similar environments, who were referred to the clinic after being found to be C282Y homozygotes and to have abnormal LFTs. One sister had developed features of haemochromatosis and the other had developed NASH. These cases illustrate the potential non-penetrance of HFE gene mutations and the need to investigate abnormal LFTs fully, even when there is a positive genetic test at the outset.


Assuntos
Fígado Gorduroso/genética , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Fígado Gorduroso/complicações , Fígado Gorduroso/metabolismo , Feminino , Hemocromatose/metabolismo , Proteína da Hemocromatose , Homozigoto , Humanos , Ferro/análise , Fígado/química , Testes de Função Hepática , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Irmãos
15.
Biochem Soc Trans ; 31(Pt 6): 1260-2, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14641038

RESUMO

Several protein toxins, including the A chain of the plant protein ricin (RTA), enter mammalian cells by endocytosis and catalytically modify cellular components to disrupt essential cellular processes. In the case of ricin, the process inhibited is protein synthesis. In order to reach their cytosolic substrates, several toxins undergo retrograde transport to the ER (endoplasmic reticulum) before translocating across the ER membrane. To achieve this export, these toxins exploit the ERAD (ER-associated protein degradation) pathway but must escape, at least in part, the normal degradative fate of ERAD substrates in order to intoxicate the cell. Toxins that translocate from the ER have an unusually low lysine content that reduces the likelihood of ubiquitination and ubiquitin-mediated proteasomal degradation. We have changed the two lysyl residues normally present in RTA to arginyl residues. Their replacement in RTA did not have a significant stabilizing effect on the protein, suggesting that the endogenous lysyl residues are not sites for ubiquitin attachment. However, when four additional lysyl residues were introduced into RTA in a way that did not compromise the activity, structure or stability of the toxin, degradation was significantly enhanced. Enhanced degradation resulted from ubiquitination that predisposed the toxin to proteasomal degradation. Treatment with the proteasomal inhibitor lactacystin increased the cytotoxicity of the lysine-enriched RTA to a level approaching that of wild-type RTA.


Assuntos
Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Toxinas Biológicas/metabolismo , Transporte Proteico
16.
Heart ; 89(9): 1023-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12923017

RESUMO

OBJECTIVES: Excess iron stores have been postulated to enhance the risk of ischaemic heart disease. This study aims to determine whether the two major mutations of the haemochromatosis (HFE) gene (C282Y and H63D) are associated with ischaemic heart disease (IHD) or myocardial infarction (MI). DESIGN: Cross sectional case-control study. SETTING: The geographical area studied by the MONICA (monitoring trends and determinants in cardiovascular disease) heart attack register for North Glasgow in Scotland, UK. PATIENTS: 1009 control subjects chosen at random from general practitioner registers were studied. Additionally, 924 subjects who had survived a first MI sustained between 1985 and 1992 were identified from the MONICA register. MAIN OUTCOME MEASURES: C282Y and H63D mutations, previous MI, and presence or absence of IHD. RESULTS: Mutant gene prevalences in the whole control population were as follows: C282Y: homozygote 0.9%, heterozygote 17.7%; H63D: homozygote 2.1%, heterozygote 25.5%; and compound heterozygote: 2.4%. Analysis by chi(2) test and logistic regression analysis did not identify any significant difference in genotype prevalence between normal control, IHD control, and MI survivor groups. CONCLUSIONS: The C282Y homozygote and heterozygote prevalences are among the highest reported worldwide. No association between IHD or MI and HFE genotype was identified. However, these results need to be interpreted in the light of the cross sectional case-control nature of the study.


Assuntos
Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Mutação/genética , Isquemia Miocárdica/genética , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Frequência do Gene , Genótipo , Hemocromatose/epidemiologia , Proteína da Hemocromatose , Heterozigoto , Homozigoto , Humanos , Modelos Logísticos , Masculino , Isquemia Miocárdica/epidemiologia , Prevalência , Análise de Regressão , Escócia/epidemiologia
17.
Vet Immunol Immunopathol ; 93(1-2): 39-49, 2003 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12753774

RESUMO

Immunization of cattle with in vitro propagated bovine mononuclear cells infected with Theileria annulata induces a protective immune response. Activation and effector function of T cells exiting the lymph node draining the site of cell line immunization were investigated to understand the mechanisms involved in the generation of immunity. Immunized animals exhibited a biphasic immune response in efferent lymph as well as peripheral blood. The first phase corresponded to allogenic responses against MHC antigens of the immunizing cell line and the second was associated with parasite specific responses. An increase in the output of CD2(+) cells and MHC class II(+) cells in efferent lymph was observed after cell line immunization with a corresponding decrease in WC1(+) cells. Although the percentage of CD4(+) T cells did not change significantly over the course of the experiment, they became activated. Both CD25 and MHC class II expressing CD4(+) T cells were detected from day 7 onwards, peaking around day 13. Efferent lymph leukocytes (ELL) exhibited sustained responses to IL-2 in vitro following cell line immunization. Antigen specific proliferation was also detected first to the immunizing cell line and then to parasite antigens. The two peaks of CD2(+) cells were observed, which corresponded to similar peaks of CD8(+) cells. The increase in CD8(+) cells was more pronounced during the second parasite specific phase than the first allogenic phase. Activated CD8(+) T cells mainly expressed MHC class II and some expressed CD25. Significantly the peak of activated CD4(+) T cells preceded the peak of activated CD8(+) T cells, highlighting the role of T. annulata specific CD4(+) T cells in inducing parasite specific CD8(+) cytotoxic responses. A biphasic cytotoxic response also appeared in efferent lymph and peripheral blood, the first directed against MHC antigens of the immunizing cell line followed by MHC class I restricted parasite specific cytotoxicity. The cytotoxic responses in efferent lymph appeared earlier than peripheral blood, suggesting that activated CD8(+) cells exiting the draining lymph node following immunization with T. annulata infected schizonts play an important role in the development of protective immune responses.


Assuntos
Linfócitos/imunologia , Theileria annulata/imunologia , Theileriose/imunologia , Theileriose/patologia , Vacinação/métodos , Animais , Bovinos , Divisão Celular , Linhagem Celular , Citotoxicidade Imunológica , Linfa/imunologia , Linfa/parasitologia , Linfonodos/imunologia , Linfonodos/parasitologia , Ativação Linfocitária , Linfócitos/citologia , Theileriose/prevenção & controle , Fatores de Tempo
18.
Br J Cancer ; 88(10): 1622-30, 2003 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-12771932

RESUMO

We have generated fusion proteins between vascular endothelial growth factor (VEGF) and the bacterial enzyme carboxypeptidase G2 (CPG2) that can activate the prodrug 4-[(2-chloroethyl)(2-mesyloxyethyl)amino]benzoyl-L-glutamic acid (CMDA). Three asparagine residues of CPG2 were mutated to glutamine (CPG2(Q)3) to prevent glycosylation during secretion, and truncations of VEGF(165) were fused to either the C- or N-terminal of CPG2. The K(m) of the fusion proteins (37.5 microM) was similar to that of secreted CPG2(Q)3 (29.5 microM) but greater than that of wild-type CPG2 (8 microM). The affinity of the fusion proteins for VEGF receptor-2 (VEGFR2) (K(d)=0.5-1.1 nM) was similar to that of [(125)I]VEGF (K(d)=0.5 nM) (ELISA) or slightly higher (K(d)=1.3-9.6 nM) (competitive RIA). One protein, VEGF(115)-CPG2(Q)3-H(6), possessed 140% of the enzymic activity of secreted CPG2(Q)3, and had a faster half-maximal binding time for VEGFR2 (77 s), than the other candidates (330 s). In vitro, VEGF(115)-CPG2(Q)3-H(6) targeted CMDA cytotoxicity only towards VEGFR-expressing cells. The plasma half-life of VEGF(115)-CPG2(Q)3-H(6) in vivo was 3 h, comparable to equivalent values observed in ADEPT. We conclude that enzyme prodrug therapy using VEGF as a targeting moiety represents a promising novel antitumour therapy, with VEGF(115)-CPG2(Q)3-H(6) being a lead candidate.


Assuntos
Fatores de Crescimento Endotelial/farmacologia , Glutamatos/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Linfocinas/farmacologia , Compostos de Mostarda Nitrogenada/farmacologia , Pró-Fármacos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , gama-Glutamil Hidrolase/farmacologia , Adenocarcinoma/patologia , Fatores de Crescimento Endotelial/genética , Endotélio/citologia , Feminino , Glutamina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Linfocinas/genética , Mutagênese Sítio-Dirigida , Neovascularização Patológica , Neoplasias Ovarianas/patologia , Plasmídeos , Mutação Puntual , Fator A de Crescimento do Endotélio Vascular , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fatores de Crescimento do Endotélio Vascular , gama-Glutamil Hidrolase/genética
19.
J Econ Entomol ; 95(5): 908-11, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12403415

RESUMO

Three laboratory experiments were performed to assess parasitization of freeze-killed house fly puparia, buried 0 to 6 cm in media, by Muscidifurax raptor Girault & Saunders, Muscidifurax raptorellus Kogan & Legner, Muscidifurax zaraptor Kogan & Legner, Trichomalopsis sarcophagae (Gahan) and Urolepis rufipes (Ashmead) (Hymenoptera: Pteromalidae). Virtually no parasitization occurred at depths greater than 1 cm in large arenas (988 cm2) with densities of 0.3 puparia and 0.008 female parasitoids per cm2. Parasitization was observed at depths as great as 4 cm for three of five species in small arenas (3 cm2) with densities of 6.4 puparia and 1.0 female per cm2. Combined across experiments, M. raptor achieved the highest level of parasitization, followed by M. zaraptor, M. raptorellus, U. rufipes, and T. sarcophagae. The greatest number of F1 females was produced by the gregarious species T. sarcophagae (834 female female) and M. raptorellus (708 female female), and then by the solitary species M. raptor (530 female female), M. zaraptor (365 female female) and U. rufipes (163 female female). High parasitization by M. raptor and high production of offspring by T. sarcophagae identify these species as being particularly attractive as biological control agents.


Assuntos
Muscidae/parasitologia , Vespas/fisiologia , Animais , Feminino , Congelamento , Masculino
20.
Gut ; 50(2): 248-52, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11788568

RESUMO

BACKGROUND: Chronic hepatitis C virus (HCV) infection is frequently associated with elevated markers of iron stores. Recessively inherited mutations in the HFE gene are responsible for iron accumulation in most cases of hereditary haemochromatosis and may have a role in HCV infection. They may also be associated with progressive liver fibrosis although this remains controversial. AIMS: To assess the prevalence of HFE mutations in Scottish HCV infected patients and to explore the effect of the carrier state on serum and liver iron stores, and the severity of liver disease. PATIENTS: A total of 164 patients with antibodies to HCV who underwent liver biopsy were assessed prospectively. METHODS: Each patient was screened for HFE mutations (Cys282Tyr and His63Asp). Iron markers were assessed in serum (ferritin, transferrin saturation) and on liver biopsy (stainable iron, liver iron concentration (LIC) and hepatic iron index). RESULTS: There were 67 (41%, 26 Cys282Tyr, 33 His63Asp, eight compound) heterozygotes. Forty four (28%) patients had elevated serum iron markers, 24 (15%) had stainable liver iron, and five (3%) had elevated LICs. Carriage of HFE mutations was not associated with any clinical, biochemical, virological, or pathological features, including accumulation of liver iron. Elevated serum iron markers were associated with male sex, increased alcohol consumption, and increased liver inflammation and fibrosis. Patients with elevated LICs were older, acquired HCV infection earlier, and had more liver inflammation. CONCLUSIONS: Patients with chronic HCV infection frequently have elevated serum iron markers although elevated LICs are uncommon. Elevated serum iron studies and LICs occur in patients with more severe liver disease. Carriage of HFE mutations, although frequently observed in these HCV infected patients, does not have a role in the accumulation of iron or the progression of liver disease in HCV infection.


Assuntos
Hemocromatose/genética , Hepatite C Crônica/genética , Ferro , Mutação/genética , Adulto , Idoso , Consumo de Bebidas Alcoólicas/sangue , Biópsia/métodos , Progressão da Doença , Feminino , Ferritinas/sangue , Hepatite C Crônica/sangue , Hepatite C Crônica/metabolismo , Heterozigoto , Humanos , Ferro/análise , Ferro/sangue , Fígado/química , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição por Sexo , Transferrina/análise
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