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2.
Eur J Clin Microbiol Infect Dis ; 36(3): 467-478, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27816993

RESUMEN

FimH-mediated adhesion of Escherichia coli to bladder epithelium is a prerequisite for urinary tract infections. FimH is also essential for blood-borne bacterial dissemination, but the mechanisms are poorly understood. The purpose of this study was to assess the influence of different FimH mutations on bacterial adhesion using a novel adhesion assay, which models the physiological flow conditions bacteria are exposed to. We introduced 12 different point mutations in the mannose binding pocket of FimH in an E. coli strain expressing type 1 fimbriae only (MSC95-FimH). We compared the bacterial adhesion of each mutant across several commonly used adhesion assays, including agglutination of yeast, adhesion to mono- and tri-mannosylated substrates, and static adhesion to bladder epithelial and endothelial cells. We performed a comparison of these assays to a novel method that we developed to study bacterial adhesion to mammalian cells under flow conditions. We showed that E. coli MSC95-FimH adheres more efficiently to microvascular endothelium than to bladder epithelium, and that only endothelium supports adhesion at physiological shear stress. The results confirmed that mannose binding pocket mutations abrogated adhesion. We demonstrated that FimH residues E50 and T53 are crucial for adhesion under flow conditions. The coating of endothelial cells on biochips and modelling of physiological flow conditions enabled us to identify FimH residues crucial for adhesion. These results provide novel insights into screening methods to determine the effect of FimH mutants and potentially FimH antagonists.


Asunto(s)
Adhesinas de Escherichia coli/genética , Adhesión Bacteriana , Escherichia coli/genética , Escherichia coli/fisiología , Proteínas Fimbrias/genética , Mutación Puntual , Sitios de Unión , Células Cultivadas , Células Endoteliales/microbiología , Células Epiteliales/microbiología , Humanos , Lectina de Unión a Manosa/genética
3.
Diabetes Obes Metab ; 15(11): 1056-60, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23701286

RESUMEN

This study explored sex differences in 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) activity and gene expression in isolated adipocytes and adipose tissue (AT), obtained via subcutaneous biopsies from non-diabetic subjects [58 M, 64 F; age 48.3 ± 15.3 years, body mass index (BMI) 27.2 ± 3.9 kg/m²]. Relationships with adiposity and insulin resistance (IR) were addressed. Males exhibited higher 11ß-HSD1 activity in adipocytes than females, but there was no such difference for AT. In both men and women, adipocyte 11ß-HSD1 activity correlated positively with BMI, waist circumference, % body fat, adipocyte size and with serum glucose, triglycerides and low-density lipoprotein:high-density lipoprotein (LDL:HDL) ratio. Positive correlations with insulin, HOMA-IR and haemoglobin A1c (HbA1c) and a negative correlation with HDL-cholesterol were significant only in males. Conversely, 11ß-HSD1 activity in AT correlated with several markers of IR and adiposity in females but not in males, but the opposite pattern was found with respect to 11ß-HSD1 mRNA expression. This study suggests that there are sex differences in 11ß-HSD1 regulation and in its associations with markers of obesity and IR.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Adiposidad , Regulación Enzimológica de la Expresión Génica , Resistencia a la Insulina , Sobrepeso/metabolismo , Grasa Subcutánea/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Biomarcadores/sangre , Biomarcadores/metabolismo , Biopsia , Índice de Masa Corporal , Tamaño de la Célula , Células Cultivadas , Femenino , Hemoglobina Glucada/análisis , Humanos , Hiperlipidemias/etiología , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/fisiopatología , Persona de Mediana Edad , Sobrepeso/complicaciones , Sobrepeso/patología , Sobrepeso/fisiopatología , ARN Mensajero/metabolismo , Caracteres Sexuales , Grasa Subcutánea/enzimología , Grasa Subcutánea/patología
4.
Health Technol Assess ; 16(5): iii-xiv, 1-195, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22340890

RESUMEN

BACKGROUND: Obesity [defined as a body mass index (BMI) ≥ 30 kg/m(2)] represents a considerable public health problem and is associated with a significant range of comorbidities and an increased mortality risk. The primary aim of the management of obesity is to achieve weight reduction in the interests of health. For obese patients who cannot achieve or maintain a healthy weight by non-pharmacological means, drug therapy is recommended in combination with non-pharmacological interventions such as dietary modifications and exercise. OBJECTIVE: To evaluate the clinical effectiveness and cost-effectiveness of three pharmacological interventions in obese patients. DATA SOURCES: Clinical effectiveness data used in the meta-analysis were sourced from articles identified in a systematic review of the literature. Data used to inform transitions to obesity-related comorbidities were derived from the General Practice Research Database (GPRD). The results of the meta-analysis and GPRD analyses informed the economic model supplemented by data from the Health Survey for England and other UK-specific data sourced from the literature. REVIEW METHODS: A systematic literature review was conducted of the clinical effectiveness and cost-effectiveness of orlistat, sibutramine and rimonabant within their licensed indications for the treatment of obese patients. Electronic bibliographic databases including MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, The Cochrane Library databases and Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched in January 2009, and the reference lists of relevant articles were checked. Studies were included if they compared orlistat, sibutramine or rimonabant with lifestyle and/or exercise advice (standard care), placebo or metformin. RESULTS: Overall, 94 studies involving 24,808 individuals were included in the clinical meta-analysis. Eighty-three trials included data on weight change, 41 included data on BMI change and 45 and 36 studies reported on 5% and 10% body weight loss, respectively. Overall, the results show that the active drug interventions are all effective at reducing weight and BMI compared with placebo. In the case of sibutramine, the higher dose (15 mg) resulted in a greater reduction than the lower dose (10 mg). Generally, the data quality of the trials included was low with poor reporting of standard errors and standard deviations. Results from the BMI risk models derived from the GPRD showed consistent increases in risk with increasing BMI. Adjustments for key confounders, such as age, sex and smoking status, were found to be statistically significant at the 5% level, in all risk models. Applying linear models to estimate BMI trajectories, for the diabetic cohort, an average increase in BMI of 0.040 per year for both men and women was observed. The non-diabetic cohort model showed an increase in BMI of 0.175 per year for women and 0.145 per year for men. The results of the cost-effectiveness analyses suggest that sibutramine 15 mg dominates the other three active interventions and the net benefit analyses show that sibutramine 15 mg is the most cost-effective alternative for thresholds > £2000 per quality-adjusted life-year (QALY). However, both sibutramine and rimonabant have been withdrawn because of safety concerns relating to potential treatment-induced fatal adverse events. If the proportion of patients who experienced a fatal adverse event was > 1.8% (1.5%, 1.0%) for sibutramine 15 mg (sibutramine 10 mg, rimonabant) the treatment would not be considered cost-effective when using a threshold of £20,000 per QALY. LIMITATIONS: The clinical review did not include all possible lifestyle comparators, with the inclusion limited to only those trials included one of the active drug interventions. We also excluded all studies not reported in English. Although the clinical review included data from 94 studies, the quality of data was generally low, particularly in terms of the reporting of standard deviation. There was also inconsistency between the results of the mixed-treatment comparison (MTC) and the pair-wise analyses. CONCLUSION: The MTC of anti-obesity treatments shows that all the active treatments are effective at reducing weight and BMI. The economic results show that, compared with placebo, the treatments are all cost-effective when using a threshold of £20,000 per QALY, and, within the limitations of the data available, sibutramine 15 mg dominates the other three interventions. This work has highlighted many areas of methodological research that could be explored, including assessing inconsistencies within a network to determine differences between the results of pair-wise and MTC analyses; the use of meta-regression methods to look for effect modifiers; exploring the effect of local publication bias; and the use of joint models to analyse the repeated measures of BMI and the time-to-event processes simultaneously. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Asunto(s)
Fármacos Antiobesidad/uso terapéutico , Ciclobutanos/uso terapéutico , Lactonas/uso terapéutico , Obesidad/tratamiento farmacológico , Piperidinas/uso terapéutico , Pirazoles/uso terapéutico , Fármacos Antiobesidad/economía , Análisis Costo-Beneficio , Ciclobutanos/economía , Costos de los Medicamentos/estadística & datos numéricos , Ejercicio Físico , Femenino , Humanos , Lactonas/economía , Masculino , Persona de Mediana Edad , Orlistat , Piperidinas/economía , Atención Primaria de Salud/economía , Atención Primaria de Salud/métodos , Pirazoles/economía , Rimonabant , Conducta de Reducción del Riesgo , Resultado del Tratamiento
5.
Health Technol Assess ; 16(50): i-xvi, 1-159, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23302507

RESUMEN

BACKGROUND: The evidence base which supported the National Institute for Health and Clinical Excellence (NICE) published Clinical Guideline 3 was limited and 50% was graded as amber. However, the use of tests as part of pre-operative work-up remains a low-cost but high-volume activity within the NHS, with substantial resource implications. The objective of this study was to identify, evaluate and synthesise the published evidence on the clinical effectiveness and cost-effectiveness of the routine use of three tests, full blood counts (FBCs), urea and electrolytes tests (U&Es) and pulmonary function tests, in the pre-operative work-up of otherwise healthy patients undergoing minor or intermediate surgery in the NHS. OBJECTIVE: The aims of this study were to estimate the clinical effectiveness and cost-effectiveness of routine pre-operative testing of FBC, electrolytes and renal function and pulmonary function in adult patients classified as American Society of Anaesthesiologists (ASA) grades 1 and 2 undergoing elective minor (grade 1) or intermediate (grade 2) surgical procedures; to compare NICE recommendations with current practice; to evaluate the cost-effectiveness of mandating or withdrawing each of these tests in this patient group; and to identify the expected value of information and whether or not it has value to the NHS in commissioning further primary research into the use of these tests in this group of patients. DATA SOURCES: The following electronic bibliographic databases were searched: (1) BIOSIS; (2) Cumulative Index to Nursing and Allied Health Literature; (3) Cochrane Database of Systematic Reviews; (4) Cochrane Central Register of Controlled Trials; (5) EMBASE; (6) MEDLINE; (7) MEDLINE In-Process & Other Non-Indexed Citations; (8) NHS Database of Abstracts of Reviews of Effects; (9) NBS Health Technology Assessment Database; and (10) Science Citation Index. To identify grey and unpublished literature, the Cochrane Register of Controlled Trials, National Research Register Archive, National Institute for Health Research Clinical Research Network Portfolio database and the Copernic Meta-search Engine were searched. A large routine data set which recorded the results of tests was obtained from Leeds Teaching Hospitals Trust. REVIEW METHODS: A systematic review of the literature was carried out. The searches were undertaken in March to April 2008 and June 2009. Searches were designed to retrieve studies that evaluated the clinical effectiveness and cost-effectiveness of routine pre-operative testing of FBC, electrolytes and renal function and pulmonary function in the above group of patients. A postal survey of current practice in testing patients in this group pre-operatively was undertaken in 2008. An exemplar cost-effectiveness model was constructed to demonstrate what form this would have taken had there been sufficient data. A large routine data set that recorded the results of tests was obtained from Leeds Teaching Hospitals Trust. This was linked to individual patient data with surgical outcomes, and regression models were estimated. RESULTS: A comprehensive and systematic search of both the clinical effectiveness and cost-effectiveness literature identified a large number of potentially relevant studies. However, when these studies were subjected to detailed review and quality assessment, it became clear that the literature provides no evidence on the clinical effectiveness and cost-effectiveness of these specific tests in the specific patient groups. The postal survey had a 17% response rate. Results reported that in ASA grade 1, patients aged < 40 years with no comorbidities undergoing minor surgery did not have routine tests for FBC, electrolytes and renal function and pulmonary function. The results from the regression model showed that the frequency of test use was not consistent with the hypothesis of their routine use. FBC tests were performed in only 58% of patients in the data set and U&E testing was carried out in only 57%. LIMITATIONS: Systematic searches of the clinical effectiveness and cost-effectiveness literature found that there is no evidence on the clinical effectiveness or cost-effectiveness of these tests in this specific clinical context for the NHS. A survey of NHS hospitals found that respondent trusts were implementing current NICE guidance in relation to pre-operative testing generally, and a de novo analysis of routine data on test utilisation and post-operative outcome found that the tests were not be used in routine practice; rather, use was related to an expectation of a more complex clinical case. The paucity of published evidence is a limitation of this study. The studies included relied on non-UK health-care systems data, which may not be transferable. The inclusion of non-randomised studies is associated with an increased risk of bias and confounding. Scoping work to establish the likely mechanism of action by which tests would impact upon outcomes and resource utilisation established that the cause of an abnormal test result is likely to be a pivotal determinant of the cost-effectiveness of a pre-operative test and therefore evaluations would need to consider tests in the context of the underlying risk of specific clinical problems (i.e. risk guided rather than routine use). CONCLUSIONS: The time of universal utilisation of pre-operative tests for all surgical patients is likely to have passed. The evidence we have identified, though weak, indicates that tests are increasingly utilised in patients in whom there is a reason to consider an underlying raised risk of a clinical abnormality that should be taken into account in their clinical management. It is likely that this strategy has led to substantial resource savings for the NHS, although there is not a published evidence base to establish that this is the case. The total expenditure on pre-operative tests across the NHS remains significant. Evidence on current practice indicates that clinical practice has changed to such a degree that the original research question is no longer relevant to UK practice. Future research on the value of these tests in pre-operative work-up should be couched in terms of the clinical effectiveness and cost-effectiveness in the identification of specific clinical abnormalities in patients with a known underlying risk. We suggest that undertaking a multicentre study making use of linked, routinely collected data sets would identify the extent and nature of pre-operative testing in this group of patients. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Asunto(s)
Recuento de Células Sanguíneas , Pruebas Diagnósticas de Rutina , Procedimientos Quirúrgicos Electivos , Electrólitos/sangre , Pruebas de Función Respiratoria , Urea/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células Sanguíneas/economía , Comorbilidad , Análisis Costo-Beneficio , Pruebas Diagnósticas de Rutina/economía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios/economía , Cuidados Preoperatorios/métodos , Pruebas de Función Respiratoria/economía , Medicina Estatal , Reino Unido , Adulto Joven
6.
Health Technol Assess ; 15(16): iii-xiv, 1-62, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21466760

RESUMEN

BACKGROUND: Stickler syndrome, also known as hereditary progressive arthro-ophthalmopathy, is an inherited progressive disorder of the collagen connective tissues. Manifestations include short-sightedness, cataracts, retinal problems leading to retinal detachment and possible blindness. This is principally the case among individuals with type 1 Stickler Syndrome. It is the most commonly identified inherited cause of retinal detachment in childhood. However, there is no consensus regarding best practice and no current guidelines on prophylactic interventions for this population. OBJECTIVES: The aim of this systematic review was to assess the evidence for the clinical effectiveness and safety of primary prophylactic interventions for the prevention of retinal detachment in previously untreated eyes without retinal detachment in patients with Stickler syndrome. The primary outcome of interest was retinal detachment post prophylaxis. DATA SOURCES: A systematic search was made of 11 databases of published and unpublished literature, which included MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing and Allied Health Literature and The Cochrane Library. There was no restriction by language or date. The references of all included studies were checked for further relevant citations and authors of studies with potentially relevant data were also contacted. REVIEW METHODS: Two reviewers double-screened all titles and abstracts of the citations retrieved by the search to identify studies that satisfied the inclusion criteria. Both reviewers also independently extracted and quality assessed all included studies. A narrative synthesis was performed. RESULTS: The literature search identified 1444 unique citations, of which four studies satisfied the inclusion criteria. The two principal studies were both retrospective cohort studies with control groups in populations with type 1 Stickler syndrome. One study evaluated 360° cryotherapy (n = 204) and the other focal or circumferential laser treatment (n = 22). Both studies reported a statistically significant difference in the rate of retinal detachment per eye between the groups receiving prophylaxis and the controls. However, both studies were subject to a high risk of bias. The results of the two supporting studies of Wagner-Stickler patients were either relatively inconsistent or unreliable. No study reported any major or long-term complications associated with the interventions. Despite the weaknesses of the evidence, the rate of retinal detachment in the intervention groups, especially the cryotherapy group, was lower than the rate either experienced in the study control groups or reported in other studies of untreated Stickler syndrome populations not exposed to prophylaxis. CONCLUSIONS: Only 360° cryotherapy and focal and circumferential laser treatment have been evaluated for the type 1 Stickler syndrome population, and then only by a single retrospective, controlled, cohort study in each case. Both of these studies report a significant difference between intervention and control groups (principally no treatment) and no major or long-term side effects or complications. However, there is a high risk of bias within these two studies, so the relative effectiveness of either intervention is uncertain. FUTURE WORK: A service priority is to determine reliably the prevalence of Stickler syndrome, i.e. how many individuals have type 1 or type 2 Stickler syndrome, and their risk of retinal detachment and subsequent blindness. A non-randomised, prospective cohort comparison study, in which eligible participants are treated, followed-up and analysed in one of three study arms, for no treatment, laser therapy or cryotherapy, would potentially offer further certainty in terms of the relative efficacy of both prophylaxis versus no prophylaxis and cryotherapy versus laser therapy than is possible with the currently available data. Alternatively, continued follow-up and analysis of existing study data, and data collection from relevant sample populations, are required to assess the long-term risks of blindness, retinal detachment and prophylaxis. FUNDING: This study was funded by the National Institute for Health Research Health Technology Assessment programme.


Asunto(s)
Ceguera/prevención & control , Desprendimiento de Retina/prevención & control , Adulto , Factores de Edad , Artritis/complicaciones , Artritis/cirugía , Artritis/terapia , Ceguera/etiología , Niño , Colágeno Tipo XI/deficiencia , Enfermedades del Tejido Conjuntivo/complicaciones , Enfermedades del Tejido Conjuntivo/cirugía , Enfermedades del Tejido Conjuntivo/terapia , Crioterapia , Pérdida Auditiva Sensorineural/complicaciones , Pérdida Auditiva Sensorineural/cirugía , Pérdida Auditiva Sensorineural/terapia , Humanos , Terapia por Láser , Desprendimiento de Retina/complicaciones , Desprendimiento de Retina/etiología , Desprendimiento de Retina/cirugía , Desprendimiento de Retina/terapia , Medición de Riesgo , Factores de Riesgo , Desprendimiento del Vítreo/complicaciones , Desprendimiento del Vítreo/cirugía , Desprendimiento del Vítreo/terapia
7.
Int J Surg Oncol ; 2011: 406517, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22312505

RESUMEN

Introduction. The aim of this study was to examine the effect of surgeon relocation on lymph node (LN) retrieval in colorectal cancer (CRC) resection. Methods. The study population was 213 consecutive patients undergoing CRC resection by a single surgeon, at two units: unit one 110 operations (2002-2005) and unit two 103 (2005-2009). LN yields and case mix were compared. Results. Median LN harvests were significantly different between the two centres: unit 1: 13 nodes/patient and unit 2: 22 nodes/patient (P < .001). In unit one 42% of cases were LN positive and in unit two 48% (P = .398). There was no difference in case mix. Multivariate analysis identified unit (P < .001) and pathologist (P = .007) as independent predictors of harvest. Conclusions. A surgeon moving units can experience significantly different LN yield following CRC resection. Both units comply with national standards, but the "surgeon's results" at the two units appear to be pathologist dependent. This has implications for nodal harvest as a surrogate marker of surgical quality.

8.
Health Technol Assess ; 14(Suppl. 2): 47-53, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21047491

RESUMEN

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of bevacizumab in combination with fluoropyrimidine-based chemotherapy for the first-line treatment of metastatic colorectal cancer based on the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. Evidence was available in the form of one phase III, multicentre, multinational, randomised, open-label study (NO16966 trial). This two-arm study was originally designed to demonstrate the non-inferiority of oral capecitabine plus oxaliplatin (XELOX) compared with 5-fluorouracil plus folinic acid plus oxaliplatin (FOLFOX)-4 in adult patients with histologically confirmed metastatic colorectal cancer who had not previously been treated. Following randomisation of 634 patients, the open-label study was amended to include a 2 × 2 factorial randomised (partially blinded for bevacizumab) phase III trial with the coprimary objective of demonstrating superiority of bevacizumab in combination with chemotherapy compared with chemotherapy alone. Measured outcomes included overall survival, progression-free survival, response rate, adverse effects of treatment and health-related quality of life. The manufacturer's primary pooled analysis of superiority (using the intention-to-treat population) showed that after a median follow-up of 28 months, the addition of bevacizumab to chemotherapy significantly improved progression-free survival and overall survival compared with chemotherapy alone in adult patients with histologically confirmed metastatic colorectal cancer who were not previously treated [median progression-free survival 9.4 vs 7.7 months (absolute difference 1.7 months); hazard ratio (HR) 0.79, 97.5% confidence interval (CI) 0.72 to 0.87; p = 0.0001; median overall survival 21.2 vs 18.9 months (absolute difference 2.3 months); HR 0.83, 97.5% CI 0.74 to 0.93; p = 0.0019]. The NO16966 trial was of reasonable methodological quality and demonstrated a significant improvement in both progression-free survival and overall survival when bevacizumab was added to XELOX or FOLFOX. However, the size of the actual treatment effect of bevacizumab is uncertain. The ERG believed that the modelling structure employed was appropriate, but highlighted several key issues and areas of uncertainty. At the time of writing, NICE was yet to issue the guidance for this appraisal.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/economía , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/economía , Anticuerpos Monoclonales Humanizados , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/economía , Protocolos de Quimioterapia Combinada Antineoplásica/economía , Bevacizumab , Ensayos Clínicos Fase III como Asunto , Neoplasias Colorrectales/economía , Neoplasias Colorrectales/patología , Análisis Costo-Beneficio , Inglaterra , Fluorouracilo/administración & dosificación , Fluorouracilo/economía , Humanos , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Gales
9.
Health Technol Assess ; 14(47): 1-108, iii-iv, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21029717

RESUMEN

BACKGROUND: Prostate cancer (PC) is the most common cancer in men in the UK. Radiotherapy (RT) is a recognised treatment for PC and high-dose conformal radiotherapy (CRT) is the recommended standard of care for localised or locally advanced tumours. Intensity-modulated radiotherapy (IMRT) allows better dose distributions in RT. OBJECTIVE: This report evaluates the clinical effectiveness and cost-effectiveness of IMRT for the radical treatment of PC. DATA SOURCES: The following databases were searched: MEDLINE (1950-present), EMBASE (1980-present), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982-present), BIOSIS (1985-present), the Cochrane Database of Systematic Reviews (1991-present), the Cochrane Controlled Trials Register (1991-present), the Science Citation Index (1900-present) and the NHS Centre for Reviews and Dissemination databases (Database of Abstracts of Reviews of Effects, NHS Economic Evaluation Database, Health Technology Assessment) (1991-present). MEDLINE In-Process & Other Non-Indexed Citations was searched to identify any studies not yet indexed on MEDLINE. Current research was identified through searching the UK Clinical Research Network, National Research Register archive, the Current Controlled Trials register and the Medical Research Council Clinical Trials Register. In addition, abstracts of the American Society of Clinical Oncology, the American Society for Therapeutic Radiology and Oncology, and European Society for Therapeutic Radiology and Oncology conferences were browsed. REVIEW METHODS: A systematic literature review of the clinical effectiveness and cost-effectiveness of IMRT in PC was conducted. Comparators were three-dimensional conformal radiotherapy (3DCRT) or radical prostatectomy. Outcomes sought were overall survival, biochemical [prostate-specific antigen (PSA)] relapse-free survival, toxicity and health-related quality of life (HRQoL). Fifteen electronic bibliographic databases were searched in January 2009 and updated in May 2009, and the reference lists of relevant articles were checked. Studies only published in languages other than English were excluded. An economic model was developed to examine the cost-effectiveness of IMRT in comparison to 3DCRT. Four scenarios were modelled based on the studies which reported both PSA survival and late gastrointestinal (GI) toxicity. In two scenarios equal PSA survival was assumed for IMRT and 3DCRT, the other two having greater PSA survival for the IMRT cohort. As there was very limited data on clinical outcomes, the model estimates progression to clinical failure and PC death from the surrogate outcome of PSA failure. RESULTS: No randomised controlled trials (RCTs) of IMRT versus 3DCRT in PC were available, but 13 non-randomised studies comparing IMRT with 3DCRT were found, of which five were available only as abstracts. One abstract reported overall survival. Biochemical relapse-free survival was not affected by treatment group, except where there was a dose difference between groups, in which case higher dose IMRT was favoured over lower dose 3DCRT. Most studies reported an advantage for IMRT in GI toxicity, attributed to increased conformality of treatment compared with 3DCRT, particularly with regard to volume of rectum treated. There was some indication that genitourinary toxicity was worse for patients treated with dose escalated IMRT, although most studies did not find a significant treatment effect. HRQoL improved for both treatment groups following radiotherapy, with any group difference resolved by 6 months after treatment. No comparative studies of IMRT versus prostatectomy were identified. No comparative studies of IMRT in PC patients with bone metastasis were identified. LIMITATIONS: The strength of the conclusions of this review are limited by the lack of RCTs, and any comparative studies for some patient groups. CONCLUSIONS: The comparative data of IMRT versus 3DCRT seem to support the theory that higher doses, up to 81 Gy, can improve biochemical survival for patients with localised PC, concurring with data on CRT. The data also suggest that toxicity can be reduced by increasing conformality of treatment, particularly with regard to GI toxicity, which can be more easily achieved with IMRT than 3DCRT. Whether differences in GI toxicity between IMRT and 3DCRT are sufficient for IMRT to be cost-effective is uncertain, depending on the difference in incidence of GI toxicity, its duration and the cost difference between IMRT and 3DCRT.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada/economía , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis Costo-Beneficio , Humanos , Masculino , Persona de Mediana Edad , Modelos Económicos , Estadificación de Neoplasias , Neoplasias de la Próstata/economía , Neoplasias de la Próstata/patología , Años de Vida Ajustados por Calidad de Vida , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/instrumentación , Medicina Estatal , Estadística como Asunto , Sobrevivientes , Resultado del Tratamiento , Reino Unido
10.
Health Technol Assess ; 13 Suppl 3: 43-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19846028

RESUMEN

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of rivaroxaban for the prevention of venous thromboembolism (VTE) in adult patients undergoing elective hip or knee replacement surgery based upon a review of the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The submission's evidence came from four randomised controlled trials (RCTs) comparing rivaroxaban with enoxaparin [RECORD (Regulation of Coagulation in Orthopedic surgery to pRevent Deep venous thrombosis and pulmonary embolism) 1-4] and three comparing dabigatran with enoxaparin [RE-NOVATE (the prevention of venous thromboembolism after total hip replacement trial), RE-MODEL (the prevention of venous thromboembolism after total knee replacement trial) and RE-MOBILIZE (the prevention of venous thromboembolism after total knee arthroplasty trial)]. The evidence from the four RECORD trials indicates that rivaroxaban had superior efficacy over enoxaparin after total hip replacement (THR) and total knee replacement (TKR). For the composite primary outcome of any deep vein thrombosis (DVT), non-fatal pulmonary embolism (PE) and death from all causes the relative risk reductions were 70-79% in THR and 31-49% in TKR. Rivaroxaban also had superior efficacy over enoxaparin for the secondary outcome major VTE. Rivaroxaban was not inferior to enoxaparin on the safety outcome of major bleeding. After the correction of some errors found by the ERG, the manufacturer's economic model represented a reasonable model of patients receiving prophylaxis for THR or TKR. In the base-case analyses rivaroxaban dominated both enoxaparin and dabigatran. The incremental costs saved and quality-adjusted life-years (QALYs) gained were small (below 200 pounds and 0.005, respectively, per person). Analyses were conducted sampling from the distributions observed from the RCTs. When all parameters were sampled rivaroxaban dominated enoxaparin in all scenarios except for two, in which enoxaparin produced more QALYs than rivaroxaban and had an incremental cost per QALY gained of 5000 pounds and 8000 pounds respectively. Rivaroxaban dominated dabigatran when RECORD 1 and RECORD 2, individually or pooled, were compared with RE-NOVATE and when all four rivaroxaban RCTs pooled were compared with all three dabigatran RCTs. Dabigatran dominated rivaroxaban comparing RECORD 4 with RE-MODEL and RE-MOBILIZE, and was more cost-effective than rivaroxaban comparing RECORD 3 (incremental cost per QALY gained of rivaroxaban compared with dabigatran of 123,000 pounds) or RECORD 3 and RECORD 4 pooled (incremental cost per QALY gained of dabigatran compared with rivaroxaban of 400 pounds) with RE-MODEL and RE-MOBILIZE. In conclusion, the evidence indicates that rivaroxaban is not inferior to enoxaparin in terms of the primary and secondary outcomes. The submission presents a reasonable estimation of the cost-effectiveness of rivaroxaban compared with enoxaparin and dabigatran, although the uncertainty in the decision has been underestimated. The results are particularly sensitive to any assumed difference in the number of fatal PEs, but the ERG does not believe there is sufficient evidence to support a difference between interventions. The NICE guidance issued as a result of the STA states that: riveroxaban, within its marketing authorisation, is recommended as an option for the prevention of venous thromboembolism in adults having elective THR or elective TKB.


Asunto(s)
Anticoagulantes/uso terapéutico , Morfolinas/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Tiofenos/uso terapéutico , Tromboembolia Venosa/prevención & control , Adulto , Anticoagulantes/economía , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Análisis Costo-Beneficio , Humanos , Morfolinas/economía , Complicaciones Posoperatorias/economía , Ensayos Clínicos Controlados Aleatorios como Asunto , Rivaroxabán , Tiofenos/economía , Tromboembolia Venosa/economía , Tromboembolia Venosa/etiología
11.
Health Technol Assess ; 13(5): iii, xi-xiii 1-219, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19128541

RESUMEN

OBJECTIVES: To provide an evidence-based perspective on the prognostic value of novel markers in localised prostate cancer and to identify the best prognostic model including the three classical markers and investigate whether models incorporating novel markers are better. DATA SOURCES: Eight electronic bibliographic databases were searched during March-April 2007. The reference lists of relevant articles were checked and various health services research-related resources consulted via the internet. The search was restricted to publications from 1970 onwards in the English language. METHODS: Selected studies were assessed, data extracted using a standard template, and quality assessed using an adaptation of published criteria. Because of the heterogeneity regarding populations, outcomes and study type, meta-analyses were not undertaken and the results are presented in tabulated format with a narrative synthesis of the results. RESULTS: In total 30 papers met the inclusion criteria, of which 28 reported on prognostic novel markers and five on prognostic models. A total of 21 novel markers were identified from the 28 novel marker studies. There was considerable variability in the results reported, the quality of the studies was generally poor and there was a shortage of studies in some categories. The marker with the strongest evidence for its prognostic significance was prostate-specific antigen (PSA) velocity (or doubling time). There was a particularly strong association between PSA velocity and prostate cancer death in both clinical and pathological models. In the clinical model the hazard ratio for death from prostate cancer was 9.8 (95% CI 2.8-34.3, p < 0.001) in men with an annual PSA velocity of more than 2 ng/ml versus an annual PSA velocity of 2 ng/ml or less; similarly, the hazard ratio was 12.8 (95% CI 3.7-43.7, p < 0.001) in the pathological model. The quality of the prognostic model studies was adequate and overall better than the quality of the prognostic marker studies. Two issues were poorly dealt with in most or all of the prognostic model studies: inclusion of established markers and consideration of the possible biases from study attrition. Given the heterogeneity of the models, they cannot be considered comparable. Only two models did not include a novel marker, and one of these included several demographic and co-morbidity variables to predict all-cause mortality. Only two models reported a measure of model performance, the C-statistic, and for neither was it calculated in an external data set. It was not possible to assess whether the models that included novel markers performed better than those without. CONCLUSIONS: This review highlighted the poor quality and heterogeneity of studies, which render much of the results inconclusive. It also pinpointed the small proportion of models reported in the literature that are based on patient cohorts with a mean or median follow-up of at least 5 years, thus making long-term predictions unreliable. PSA velocity, however, stood out in terms of the strength of the evidence supporting its prognostic value and the relatively high hazard ratios. There is great interest in PSA velocity as a monitoring tool for active surveillance but there is as yet no consensus on how it should be used and, in particular, what threshold should indicate the need for radical treatment.


Asunto(s)
Biomarcadores de Tumor , Pronóstico , Neoplasias de la Próstata/diagnóstico , Biomarcadores de Tumor/clasificación , Humanos , Masculino , Evaluación de Procesos y Resultados en Atención de Salud , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Antígeno Prostático Específico , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Factores de Riesgo , Análisis de Supervivencia , Evaluación de la Tecnología Biomédica
12.
Colorectal Dis ; 10(2): 157-64, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17477849

RESUMEN

OBJECTIVE: An adequate lymph node harvest is necessary for accurate Dukes' stage discrimination in colorectal cancer. The aim of this study is to identify the effect of variables, including the individual surgeon and pathologist, on lymph node harvest in a single institution. METHOD: Three hundred and eighty one consecutive patients had resection for colorectal cancer, in a single unit. Factors influencing lymph node retrieval, including individual surgeon and reporting pathologist, were subjected to uni- and multivariate analysis. Actuarial survival of all patients with Dukes' stage B and C disease was then calculated and survival compared between Dukes' stage B and C at differing levels of lymph node harvest. RESULTS: The unit median lymph node harvest was 13 nodes/patient (95% CI 13.1-14.5). There was no difference in lymph node harvest between specialist colorectal surgeons and the pooled results of four nonspecialist consultant surgeons. However, there was a significant difference between reporting pathologists (P < 0.001). On univariate analysis, operation type, operative urgency, Dukes' stage, T-stage, reporting pathologist and use of neoadjuvant therapy in rectal cancer, were found to significantly affect lymph node retrieval. On multivariate analysis, operation type, T-stage, reporting pathologist and neoadjuvant therapy in rectal cancer remained significant variables. Patients with one or more lymph node metastasis had greater nodal harvests than those without (median 15 vs 12 P = 0.02). Survival of patients with Dukes' stage B disease was found to improve as lymph node harvest increased. CONCLUSION: Overall lymph node harvest, in this unit, varied according to the reporting pathologist but not operating surgeon. As lymph node harvest increased to 15 per patient, the probability of identifying a metastatic node increased.


Asunto(s)
Adenocarcinoma/patología , Adenocarcinoma/cirugía , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Escisión del Ganglio Linfático , Pautas de la Práctica en Medicina/estadística & datos numéricos , Distribución de Chi-Cuadrado , Femenino , Humanos , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Estudios Prospectivos , Análisis de Regresión , Estadísticas no Paramétricas , Tasa de Supervivencia
13.
Health Technol Assess ; 11(40): 1-144, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17903394

RESUMEN

OBJECTIVES: To estimate the clinical effectiveness and cost-effectiveness of docetaxel and paclitaxel compared with non-taxane, anthracycline-containing chemotherapy regimens, for the adjuvant treatment of women with early-stage breast cancer. DATA SOURCES: Major electronic databases were searched between October 2005 and February 2006. REVIEW METHODS: A systematic review of the literature on adjuvant taxane versus anthracycline non-taxane chemotherapy for women with early breast cancer was undertaken. A mathematical model was developed to synthesise the available data on costs, disease-free survival and health-related quality of life (HRQoL) of patients receiving taxane-containing chemotherapy versus non-taxane-containing chemotherapy. RESULTS: Eight of the 11 selected trials (six docetaxel and five paclitaxel) reported a significant improvement in disease-free survival (DFS) or time to recurrence (TTR) for taxanes over comparator regimens. Docetaxel was associated with more adverse events than paclitaxel, most notably febrile neutropenia. Taxanes produced cardiotoxicity, although this was not reported to be greater than for anthracycline comparator arms in all trials. Treatment-related deaths were uncommon. Where reported, all chemotherapy regimens caused HRQoL to deteriorate during treatment. Following treatment, there were no clinically significant differences between taxane and comparator treatment groups. There were few data available comparing licensed regimens of taxanes with chemotherapy regimens commonly used in the UK. The three trials selected as the basis for the economic analysis were those that used the taxanes in accordance with current UK marketing authorisation and had also reported in full. The estimated incremental cost-effectiveness ratio for docetaxel compared to FAC6, based on the BCIRG 001 study, is 12,000 pounds (7000-39,000 pounds) and for paclitaxel compared with Adriamycin/cyclophosphamide, based on the NSABP B28 and CALGB 9344 studies, is 43,000 pounds (16,000 pounds-dominated) and 39,000 pounds (12,000 pounds-dominated), respectively. However, the comparators used in these trials restrict the generalisability of the results, as they do not conform to current standard care in the UK, typically FEC6 and E4-CMF4. An exploratory indirect comparison shows that the benefits of taxane containing regimens compared to regimens in current use in the UK is subject to large uncertainty due to the lack of direct trial comparisons between these interventions. Assumptions regarding the benefits in the taxane arm after the trial follow-up period and the annual rate of recurrence in this period have the most significant influence on the ICER. CONCLUSIONS: There is a large degree of heterogeneity in the evidence base for the effectiveness of taxane- compared with non-taxane-containing regimens in terms of the interventions, comparators and populations. Eight of the 11 trials providing effectiveness data reported a significant improvement in DFS or TTR for taxanes over comparator regimens. The remaining three trials found no significant differences between the groups in DFS/TTR. The cost-effectiveness results suggest that the cost per quality-adjusted life-year for taxane- compared with non-taxane-containing chemotherapy varies between 12,000 pounds and 43,000 pounds, depending on the taxane under consideration and the specific trial used as the basis of the analysis. However, the comparators used in these trials do not conform to current standard care in the UK. More research is needed, comparing taxanes used in line with their current UK marketing authorisation and with anthracycline-containing regimens commonly used in the UK. The on-going TACT trial is expected to provide useful data. There are currently few data on the effectiveness of taxanes for the over-70s. Further research is required into the long-term outcomes of taxane therapy, such as whether there are any long-term adverse events that significantly impact on overall survival or quality of life and whether the increases in DFS will translate into increases in overall survival.


Asunto(s)
Antineoplásicos Fitogénicos/economía , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Taxoides/economía , Taxoides/uso terapéutico , Antineoplásicos Fitogénicos/efectos adversos , Quimioterapia Adyuvante , Análisis Costo-Beneficio , Supervivencia sin Enfermedad , Docetaxel , Femenino , Humanos , Modelos Biológicos , Recurrencia Local de Neoplasia , Paclitaxel/efectos adversos , Paclitaxel/economía , Paclitaxel/uso terapéutico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Taxoides/efectos adversos
14.
J Psychopharmacol ; 21(4): 357-73, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17656425

RESUMEN

People with schizophrenia are at greater risk of obesity, Type 2 diabetes, dyslipidaemia and hypertension than the general population. This results in an increased incidence of cardiovascular disease (CVD) and reduced life expectancy, over and above that imposed by their mental illness through suicide. Several levels of evidence from data linkage analyses to clinical trials demonstrate that treatment-related metabolic disturbances are commonplace in this patient group, and that the use of certain second-generation antipsychotics may compound the risk of developing the metabolic syndrome and CVD. In addition, smoking, poor diet, reduced physical activity and alcohol or drug abuse are prevalent in people with schizophrenia and contribute to the overall CVD risk. Management and minimization of metabolic risk factors are pertinent when providing optimal care to patients with schizophrenia. This review recommends a framework for the assessment, monitoring and management of patients with schizophrenia in the UK clinical setting.


Asunto(s)
Antipsicóticos/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/prevención & control , Síndrome Metabólico/inducido químicamente , Síndrome Metabólico/prevención & control , Esquizofrenia/tratamiento farmacológico , Antipsicóticos/uso terapéutico , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/prevención & control , Femenino , Humanos , Hiperlipidemias/inducido químicamente , Hiperlipidemias/prevención & control , Hipertensión/inducido químicamente , Hipertensión/prevención & control , Masculino , Síndrome Metabólico/etiología , Obesidad/inducido químicamente , Obesidad/prevención & control , Guías de Práctica Clínica como Asunto , Factores de Riesgo , Esquizofrenia/complicaciones , Reino Unido , Aumento de Peso/efectos de los fármacos
15.
Int Urol Nephrol ; 39(2): 369-71, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-16835726

RESUMEN

We present a rare case of renal cell carcinoma (RCC) in a horseshoe kidney presenting as an acute left sided varicocele. A left sided varicocele is a well-described presentation of RCC, usually caused by tumour thrombus extending along the renal vein with resultant testicular vein occlusion. However, in our case a tumour in the lower pole of a horseshoe kidney caused an acute varicocele by direct involvement and occlusion of the testicular vein.


Asunto(s)
Carcinoma de Células Renales/complicaciones , Neoplasias Renales/complicaciones , Riñón/anomalías , Varicocele/etiología , Enfermedad Aguda , Carcinoma de Células Renales/diagnóstico , Humanos , Neoplasias Renales/diagnóstico , Masculino , Persona de Mediana Edad
16.
Knee Surg Sports Traumatol Arthrosc ; 15(6): 766-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17187276

RESUMEN

Foreign body in the knee is associated with trauma to knee or deliberate self harm. We see them often in clinical practice. They come in all forms and shapes. Very rarely one can find a foreign body within a joint without obvious external scarring (e.g. needle). We have not come across anywhere in the literature of a large foreign body in the knee joint without a definitive history of injury where the external scar has healed so well to become inconspicuous. With this background it is even more difficult when the X-rays mimic anterior cruciate ligament (ACL) avulsion. This case report highlights the fact that diagnosis of a foreign body in the knee joint can sometimes be challenging and almost impossible when there is no history of any injury and when the X-ray mimics ACL avulsion.


Asunto(s)
Cuerpos Extraños/diagnóstico , Vidrio , Articulación de la Rodilla/cirugía , Adulto , Lesiones del Ligamento Cruzado Anterior , Artroscopía , Diagnóstico Diferencial , Errores Diagnósticos , Femenino , Cuerpos Extraños/cirugía , Humanos , Traumatismos de la Rodilla/diagnóstico
17.
Cochrane Database Syst Rev ; (4): CD001732, 2006 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-17054141

RESUMEN

BACKGROUND: Injection sclerotherapy is widely used for superficial varicose veins. The treatment aims to obliterate the lumen of varicose veins or thread veins. There is limited evidence regarding its efficacy. OBJECTIVES: To determine whether sclerotherapy is effective in improving symptoms and cosmetic appearance and has an acceptable complication rate; to define rates of symptomatic or cosmetic varicose vein recurrence following sclerotherapy. SEARCH STRATEGY: We searched the Cochrane Peripheral Vascular Diseases Group trials register (April 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2006), MEDLINE and EMBASE (both inception to April 2006) and reference lists of articles. Manufacturers of sclerosants were contacted for additional trial information. SELECTION CRITERIA: Randomised controlled trials (RCTs) of injection sclerotherapy versus graduated compression stockings (GCS) or 'observation', or comparing different sclerosants, doses, formulations and post-compression bandaging techniques on people with symptomatic and/or cosmetic varicose veins or thread veins were considered for inclusion in the review. DATA COLLECTION AND ANALYSIS: Data were extracted by authors and Review Group Co-ordinators independently. MAIN RESULTS: Seventeen studies were included. One study comparing sclerotherapy to GCS in pregnancy found that sclerotherapy improved symptoms and cosmetic appearance. Three studies comparing sodium tetradecyl sulphate (STD) to alternative sclerosants found no significant differences in outcome or complication rates; another study found that sclerotherapy with STD led to improved cosmetic appearance compared with polidocanol, although there was no difference in symptoms. Sclerosant plus local anaesthetic reduced the pain from injection (one study) but had no other effects. Two studies compared foam- to conventional sclerotherapy; one found no difference in failure rate or recurrent varicose veins; a second showed short-term benefit from foam in terms of elimination of venous reflux. The recanalisation rate was no different between the two treatments. One study comparing Molefoam and Sorbo pad pressure dressings found no difference in erythema or successful sclerosis. The degree and duration of elastic compression had no significant effect on varicose vein recurrence rates, cosmetic appearance or symptomatic improvement. AUTHORS' CONCLUSIONS: Evidence from RCTs suggests that the choice of sclerosant, dose, formulation (foam versus liquid), local pressure dressing, degree and length of compression have no significant effect on the efficacy of sclerotherapy for varicose veins. The evidence supports the current place of sclerotherapy in modern clinical practice, which is usually limited to treatment of recurrent varicose veins following surgery and thread veins. Surgery versus sclerotherapy is the subject of a further Cochrane Review.


Asunto(s)
Escleroterapia/métodos , Várices/terapia , Vendajes , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Soluciones Esclerosantes/uso terapéutico
18.
Phys Rev Lett ; 96(15): 154504, 2006 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-16712162

RESUMEN

Ultrafast magnetic resonance imaging has been applied for the first time to measure simultaneously both the rise velocities and coalescence of bubbles, and the dynamics of the solid phase in a gas-solid two-phase flow. Here, we consider the hydrodynamics within a gas-fluidized bed of particles of diameter 0.5 mm contained within a column of internal diameter 50 mm; gas velocities in the range of 0.18-0.54 m/s were studied. The data are of sufficient temporal and spatial resolution that bubble size and the evolution of bubble size and velocity following coalescence events are determined.

19.
Clin Exp Immunol ; 127(2): 220-5, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11876743

RESUMEN

The aim of this study was to determine whether phagocytosis of necrotic or apoptotic cells affects antigen presentation by murine bone marrow-derived macrophages. After uptake of necrotic neutrophils, macrophages were able to stimulate significantly higher T cell proliferation in vitro against both the recall antigen albumin and the mitogen concanavalin A. No such effect was seen following phagocytosis of apoptotic neutrophils. Flow cytometry revealed that, within 4h of ingestion, macrophages that had taken up the necrotic cells expressed higher levels of CD40 than those that had phagocytosed apoptotic cells. Macrophage cultures pulsed with apoptotic, but not necrotic, neutrophils contained higher levels of transforming growth factor beta1, but lower concentrations of tumour necrosis factor alpha, compared to untreated controls. Our interpretation of these results is that macrophages that have taken up necrotic neutrophils co-stimulate T cells with greater efficiency due to rapid CD40 up-regulation, whereas those that have ingested apoptotic cells are not only ineffective in co-stimulation, but also secrete inhibitory cytokine.


Asunto(s)
Presentación de Antígeno , Macrófagos/inmunología , Animales , Apoptosis , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/fisiología , Antígenos CD40/biosíntesis , Antígenos CD40/genética , Células Cultivadas , Citometría de Flujo , Humanos , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Interleucina-4/biosíntesis , Activación de Linfocitos , Macrófagos/fisiología , Ratones , Ratones Endogámicos BALB C , Necrosis , Neutrófilos , Fagocitosis , Linfocitos T/inmunología , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta1 , Factor de Necrosis Tumoral alfa/biosíntesis , Regulación hacia Arriba
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