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2.
Health Technol Assess ; 12(31): 1-181, iii-iv, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18796263

RESUMO

OBJECTIVES: To evaluate the clinical effectiveness, cost-effectiveness and safety of a policy of relatively early laparoscopic surgery compared with continued medical management amongst people with gastro-oesophageal reflux disease (GORD) judged suitable for both policies. DESIGN: Relative clinical effectiveness was assessed by a randomised trial (with parallel non-randomised preference groups) comparing a laparoscopic surgery-based policy with a continued medical management policy. The economic evaluation compared the cost-effectiveness of the two management policies in order to identify the most efficient provision of future care and describe the resource impact that various policies for fundoplication would have on the NHS. SETTING: A total of 21 hospitals throughout the UK with a local partnership between surgeon(s) and gastroenterologist(s) who shared the secondary care of patients with GORD. PARTICIPANTS: The 810 participants, who were identified retrospectively or prospectively via their participating clinicians, had both documented evidence of GORD (endoscopy and/or manometry/24-hour pH monitoring) and symptoms for longer than 12 months. In addition, the recruiting clinician(s) was clinically uncertain about which management policy was best. INTERVENTION: Of the 810 eligible patients who consented to participate, 357 were recruited to the randomised arm of the trial (178 allocated to surgical management, 179 allocated to continued, but optimised, medical management) and 453 recruited to the parallel non-randomised preference arm (261 chose surgical management, 192 chose to continue with best medical management). The type of fundoplication was left to the discretion of the surgeon. MAIN OUTCOME MEASURES: Participants completed a baseline REFLUX questionnaire, developed specifically for this study, containing a disease-specific outcome measure, the Short Form with 36 Items (SF-36), the EuroQol-5 Dimensions (EQ-5D) and the Beliefs about Medicines and Surgery questionnaires (BMQ/BSQ). Postal questionnaires were completed at participant-specific time intervals after joining the trial (equivalent to approximately 3 and 12 months after surgery). Intraoperative data were recorded by the surgeons and all other in-hospital data were collected by the research nurse. At the end of the study period, participants completed a discrete choice experiment questionnaire. RESULTS: The randomised groups were well balanced at entry. Participants had been taking GORD medication for a median of 32 months; the mean age of participants was 46 years and 66% were men. Of 178 randomised to surgery, 111 (62%) actually had fundoplication. There was a mixture of clinical and personal reasons why some patients did not have surgery, sometimes related to long waiting times. A total or partial wrap procedure was performed depending on surgeon preference. Complications were uncommon and there were no deaths associated with surgery. By the equivalent of 12 months after surgery, 38% in the randomised surgical group (14% amongst those who had surgery) were taking reflux medication compared with 90% in the randomised medical group. There were substantial differences (one-third to one-half standard deviation) favouring the randomised surgical group across the health status measures, the size depending on assumptions about the proportion that actually had fundoplication. These differences were the same or somewhat smaller than differences observed at 3 months. The lower the REFLUX score, the worse the symptoms at trial entry and the larger the benefit observed after surgery. The preference surgical group had the lowest REFLUX scores at baseline. These scores improved substantially after surgery, and by 12 months they were better than those in the preference medical group. The BMQ/BSQ and discrete choice experiment did distinguish the preference groups from each other and from the randomised groups. The latter indicated that the risk of serious complications was the most important single attribute of a treatment option. A within-trial cost-effectiveness analysis suggested that the surgery policy was more costly (mean 2049 pounds) but also more effective [+0.088 quality-adjusted life-years (QALYs)]. The estimated incremental cost per QALY was 19,000-23,000 pounds, with a probability between 46% (when 62% received surgery) and 19% (when all received surgery) of cost-effectiveness at a threshold of 20,000 pounds per QALY. Modelling plausible longer-term scenarios (such as lifetime benefit after surgery) indicated a greater likelihood (74%) of cost-effectiveness at a threshold of 20,000 pounds, but applying a range of alternative scenarios indicated wide uncertainty. The expected value of perfect information was greatest for longer-term quality of life and proportions of surgical patients requiring medication. CONCLUSIONS: Amongst patients requiring long-term medication to control symptoms of GORD, surgical management significantly increases general and reflux-specific health-related quality of life measures, at least up to 12 months after surgery. Complications of surgery were rare. A surgical policy is, however, more costly than continued medical management. At a threshold of 20,000 pounds per QALY it may well be cost-effective, especially when putative longer-term benefits are taken into account, but this is uncertain. The more troublesome the symptoms, the greater the potential benefit from surgery. Uncertainty about cost-effectiveness would be greatly reduced by more reliable information about relative longer-term costs and benefits of surgical and medical policies. This could be through extended follow-up of the REFLUX trial cohorts or of other cohorts of fundoplication patients. TRIAL REGISTRATION: Current Controlled Trials ISRCTN15517081.


Assuntos
Análise Custo-Benefício , Fundoplicatura/métodos , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/cirurgia , Fármacos Gastrointestinais/economia , Fármacos Gastrointestinais/uso terapêutico , Laparoscopia/economia , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Avaliação da Tecnologia Biomédica , Resultado do Tratamento , Adulto , Análise Fatorial , Feminino , Recursos em Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Inquéritos e Questionários
3.
Br J Psychiatry ; 178: 311-6, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11282809

RESUMO

BACKGROUND: Studies of light therapy have not been conducted previously in primary care. AIMS: To evaluate light therapy in primary care. METHOD: Fifty-seven participants with seasonal affective disorder were randomly allocated to 4 weeks of bright white or dim red light. Baseline expectations for treatment were assessed. Outcome was assessed with the Structured Interview Guide for the Hamilton Depression Scale, Seasonal Affective Disorder Version. RESULTS: Both groups showed decreases in symptom scores of more than 40%. There were no differences in proportions of responders in either group, regardless of the remission criteria applied, with around 60% (74% white light, 57% red light) meeting broad criteria for response and 31% (30% white light, 33% red light) meeting strict criteria. There were no differences in treatment expectations. CONCLUSIONS: Primary care patients with seasonal affective disorder improve after light therapy, but bright white light is not associated with greater improvements.


Assuntos
Fototerapia/métodos , Atenção Primária à Saúde , Transtorno Afetivo Sazonal/terapia , Adolescente , Adulto , Afeto , Cromoterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Resultado do Tratamento
4.
J Affect Disord ; 62(3): 199-205, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11223107

RESUMO

BACKGROUND: There is a lack of published information about the consultation patterns of patients with seasonal affective disorder (SAD) in primary care, when compared with non-seasonal controls (NSCs). METHODS: Interview-confirmed SAD cases (n=90) were age- and sex-matched to two controls without significant seasonal morbidity on the Seasonal Pattern Assessment Questionnaire (SPAQ) (non-seasonal controls, NSCs). A comparison of their consultation rates was made using data abstracted from primary care records over 4 years. RESULTS: The monthly rate of general practice consultations for SAD cases was significantly higher than that for NSCs. There was a significant difference in the median number of consultations in winter and autumn between the two groups. The matched multivariate analysis revealed that February and April were the independent months in which cases of SAD had significantly more consultations than NSCs. LIMITATIONS: Optimal diagnostic criteria for SAD have not been determined and our criteria may have been over-inclusive. CONCLUSION: In addition to a marked difference in monthly consultation rates between SAD cases and NSCs, the data demonstrate a difference in the pattern of seasonality of these rates. It is possible that increased frequency of consultation, in particular during the winter months (in patients who score as a case SPAQ), could be used as an indication of SAD in primary care.


Assuntos
Medicina de Família e Comunidade/estatística & dados numéricos , Programas de Rastreamento/métodos , Visita a Consultório Médico/estatística & dados numéricos , Transtorno Afetivo Sazonal/diagnóstico , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Prontuários Médicos/estatística & dados numéricos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Escócia/epidemiologia , Transtorno Afetivo Sazonal/psicologia
5.
Br J Ophthalmol ; 84(4): 417-22, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10729302

RESUMO

BACKGROUND/AIMS: Regulation of plasmin mediated extracellular matrix degradation by vascular endothelial cells is important in the development of angiogenesis. The aim was to determine whether transforming growth factor beta (TGF-beta) affected the regulation of components of the plasminogen system by human retinal endothelial cells, in order to define more clearly the role of TGF-beta in retinal angiogenesis in the context of diabetes mellitus. METHODS: Human retinal endothelial cells (HREC) were isolated from donor eyes and used between passages 4-8. The cells were cultured in medium supplemented with 2, 5, 15, or 25 mM glucose, plus or minus TGF-beta (1 ng/ml). The concentrations of tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), and plasminogen activator inhibitor type 1 (PAI-1) in cell conditioned medium were determined by ELISA and the level of PAI-1 mRNA was determined using northern hybridisation. Cell associated plasminogen activity was determined using a clot lysis assay and a chromogenic assay. RESULTS: Under basal conditions (5 mM glucose), HREC produced PAI-1, t-PA, and trace amounts of u-PA. Cell surface plasminogen activation observed by lysis of fibrin or by cleavage of chromogenic substrate, was mediated by t-PA. Glucose at varying concentrations (2-25 mM) had no significant effect on t-PA mediated clot lysis. In contrast, treatment with TGF-beta resulted in increased synthesis of PAI-1 protein and mRNA. The increased expression of the PAI-1 mRNAs by TGF-beta did not occur uniformly, the 2.3 kb mRNA transcript was preferentially increased in comparison with the 3.2 kb mRNA (p<0.05). CONCLUSIONS: These data demonstrate that TGF-beta increases PAI-1 and decreases cell associated lysis. This is sufficient to decrease the normal lytic potential of HREC.


Assuntos
Endotélio Vascular/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativadores de Plasminogênio/metabolismo , Vasos Retinianos/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Técnicas de Cultura de Células , Endotélio Vascular/efeitos dos fármacos , Fibrina/metabolismo , Glucose/farmacologia , Humanos , Técnicas Imunoenzimáticas , Plasminogênio/fisiologia , Vasos Retinianos/efeitos dos fármacos , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
6.
Biochem J ; 344 Pt 1: 265-72, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10548560

RESUMO

The signalling mechanisms involved in the induction of nitric oxide synthase and l-arginine transport were investigated in bacterial lipopolysaccharide (LPS)- and interferon-gamma (IFN-gamma)-stimulated rat cultured aortic smooth muscle cells (RASMCs). The expression profile of transcripts for cationic amino acid transporters (CATs) and their regulation by LPS and IFN-gamma were also examined. Control RASMCs expressed mRNA for CAT-1, CAT-2A and CAT-2B. Levels of all three transcripts were significantly elevated in activated cells. Stimulated CAT mRNA expression and l-arginine transport occurred independently of protein kinase C (PKC), protein tyrosine kinase (PTK) and p44/42 mitogen-activated kinases (MAPKs), but were inhibited by the p38 MAPK inhibitor SB203580, which at 3 microM caused maximum inhibition of both responses. Induction of NO synthesis was independent of p44/42 MAPK activation and only marginally dependent on PKC, but was attenuated markedly by the PTK inhibitors genistein and herbimycin A. SB203580 differentially regulated inducible NO synthase expression and NO production, potentiating both processes at low micromolar concentrations and inhibiting at concentrations of >/=1 microM. In conclusion, our results suggest that RASMCs constitutively express transcripts for CAT-1, CAT-2A and CAT-2B, and that expression of these transcripts is significantly enhanced by LPS and IFN-gamma. Moreover, stimulation of l-arginine transport and induction of NO synthesis by LPS and IFN-gamma appear to be under critical regulation by the p38 MAPK, since both processes were significantly modified by SB203580 at concentrations so far shown to have no effect on other signalling pathways. Thus, in RASMCs, the p38 MAPK cascade represents an important signalling mechanism, regulating both enhanced l-arginine transport and induced NO synthesis.


Assuntos
Proteínas de Transporte/genética , Proteínas de Membrana/genética , Músculo Liso Vascular/metabolismo , Óxido Nítrico Sintase/genética , Sistemas de Transporte de Aminoácidos Básicos , Animais , Arginina/metabolismo , Sequência de Bases , Transporte Biológico Ativo , Células Cultivadas , Primers do DNA/genética , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica , Imidazóis/farmacologia , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II , Proteína Quinase C/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes , Transdução de Sinais
7.
Diabetologia ; 42(7): 870-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10440131

RESUMO

AIMS/HYPOTHESIS: The growth of retinal vessels is associated with a number of disease conditions, including diabetic retinopathy and proliferative vitreo-retinopathy. In this study we describe a model of human retinal angiogenesis and show how this may be used to explain the mechanisms that are associated with the growth of new retinal vessels. METHODS: A 4 mm diameter disc of retinal tissue was placed within a fibrin matrix and the appearance was monitored daily by light microscopy. Immunohistochemical techniques were used for the detection of, glial fibrillary acidic protein, CD68, the Ki-67 antigen, vascular endothelial growth factor, monocarboxylate transporter type 1 and von Willebrand's factor. RESULTS: Vessels were evident extending from the periphery of the explant and the activation of endothelial cells was shown by immuno-peroxidase staining of paraffin embedded sections of the explants for the expression of the Ki-67 antigen, a marker of cell proliferation. The expression of glial fibrillary acidic protein and von Willebrand's factor increased with duration in culture and the presence of activated macrophages or microglia or both was shown by positive immunoreactivity for CD68 and Ki-67 and were identified by day 3. The presence of endogenous vascular endothelial growth factor and the activation of monocarboxylate transporter type 1 by vascular endothelial growth factor, showed the involvement of specific growth factors. CONCLUSION/INTERPRETATION: The explant model provides evidence for the involvement of macrophages and glial fibrillary acidic protein activation in human retinal angiogenesis and for the expression of monocarboxylate transporter type 1, which is likely to be important in the use of lactate in the hypoxic retina.


Assuntos
Proteínas de Transporte/biossíntese , Neovascularização Fisiológica/fisiologia , Vasos Retinianos/crescimento & desenvolvimento , Antígenos , Colágeno , Fatores de Crescimento Endotelial/biossíntese , Endotélio Vascular/citologia , Fibrina , Expressão Gênica , Proteína Glial Fibrilar Ácida/biossíntese , Humanos , Linfocinas/biossíntese , Macrófagos/imunologia , Proteínas de Membrana , Transportadores de Ácidos Monocarboxílicos , Monócitos/metabolismo , Isoformas de Proteínas , Vasos Retinianos/fisiologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Fator de von Willebrand/biossíntese
8.
Br J Psychiatry ; 175: 472-5, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10789281

RESUMO

BACKGROUND: There are no large published studies of the prevalence of seasonal affective disorder (SAD) among UK populations. AIM: To determine the prevalence of SAD among patients attending a general practitioner (GP). METHOD: Patients aged 16-64 consulting their GPs in Aberdeen during January were screened with the Seasonal Pattern Assessment Questionnaire (SPAQ). SPAQs were also mailed to 600 matched patients, who had not consulted their GP during January. Surgery attenders who fulfilled SPAQ criteria for SAD were invited for interview to determine whether they met criteria for SAD in DSM-IV and the Structured Interview Guide for the Hamilton Rating Scale for Depression--Seasonal Affective Disorder Version (SIGH-SAD). RESULTS: Of 6161 surgery attenders, 4557 (74%) completed a SPAQ; 442 (9.7%) were SPAQ cases of SAD. Rate of caseness on the SPAQ did not differ between surgery attenders and non-attenders. Of 223 interviewed SPAQ cases of SAD, 91 (41%) also fulfilled DSM-IV and SIGH-SAD criteria. CONCLUSIONS: There is a high prevalence of SAD among patients attending their GPs in January in Aberdeen; this is likely to reflect a similar rate in the community.


Assuntos
Transtorno Afetivo Sazonal/epidemiologia , Adulto , Medicina de Família e Comunidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Razão de Chances , Prevalência , Escócia/epidemiologia , Transtorno Afetivo Sazonal/diagnóstico , Inquéritos e Questionários
9.
Br J Pharmacol ; 116(8): 3243-50, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719803

RESUMO

1. The interactions between pro-inflammatory cytokines and bacterial lipopolysaccharide (LPS) on L-arginine transporter and inducible nitric oxide synthase (iNOS) activities were examined in rat cultured aortic smooth muscle cells. 2. LPS induced a concentration (0.01-100 micrograms ml-1) and time (8-24 h)-dependent stimulation of nitrite production which was accompanied by a parallel increase in L-arginine transport. 3. Unlike LPS, activation of smooth muscle cells with either interferon-gamma (IFN-gamma, 100 u ml-1), tumour necrosis factor-alpha (TNF-alpha, 300 u ml-1) or interleukin-1 alpha (IL-1 alpha, 100 u ml-1) failed to stimulate L-arginine transport or increase nitrite accumulation. 4. When applied in combination with LPS (100 micrograms ml-1) both IFN-gamma and TNF-alpha, but not IL-1 alpha, enhanced the effects observed with LPS alone. Furthermore, activation of cells with LPS and IFN-gamma had no effect on uptake of the neutral amino acid L-citrulline but selectively increased the Vmax for L-arginine transport 2.8 fold and nitrite levels from 24 +/- 7 to 188 +/- 14 pmol micrograms-1 protein 24 h-1. 5. The substrate specificity, Na- and pH-independence of saturable L-arginine transport in both unactivated (K(m) = 44 microM, Vmax = 3 pmol micrograms-1 protein min-1) and activated (K(m) = 75 microM, Vmax = 8.3 pmol micrograms-1 protein min-1) smooth muscle cells were characteristic of the cationic amino acid transport system y+. 6. Cycloheximide (1 microM) abolished induction of L-arginine transport and nitrite accumulation in response to LPS and IFN-gamma. In contrast, the glucocorticoid dexamethasone (10 microM, 24 h) selectively inhibited nitrite production. 7. Our results demonstrate that pro-inflammatory mediators selectively enhance transport of L-arginine under conditions of sustained NO synthesis by vascular smooth muscle cells. In addition, the differential inhibition of iNOS and L-arginine transporter activity by dexamethasone suggests that distinct signalling pathways mediate induction of the cationic transport protein and iNOS. The close coupling between substrate supply and NO production may have important implications in the pathogenesis of several disease states including endotoxin shock.


Assuntos
Arginina/metabolismo , Citocinas/farmacologia , Escherichia coli , Lipopolissacarídeos/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico Sintase/biossíntese , Animais , Aorta/efeitos dos fármacos , Células Cultivadas , Cicloeximida/farmacologia , Dexametasona/farmacologia , Interações Medicamentosas , Glucocorticoides/farmacologia , Interferon gama/farmacologia , Interleucina-1/farmacologia , Masculino , Músculo Liso Vascular/metabolismo , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
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