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2.
J Oncol Pharm Pract ; 29(6): 1361-1368, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36039521

RESUMO

INTRODUCTION: Despite treatment with antiemetic medications, nausea remains uncontrolled for many children receiving chemotherapy. One reason is that risk factors for nausea in children remain poorly explored. The purpose of this study was to identify risk factors for chemotherapy-induced nausea (CIN) in children. METHODS: Prospective, observational study including 101 children (median age 6.4 years, range 0.8-17.9) with cancer receiving moderately or highly emetogenic chemotherapy. Primary endpoints were complete control of acute and delayed CIN, defined as no nausea in the acute phase 0-24 h after chemotherapy and in the delayed phase starting after the acute phase and ending 5 days later. Multivariable analyses included age, sex, cancer type, susceptibility to motion sickness, chemotherapy duration, numbers of antiemetics, co-administration with opioids or tricyclic antidepressants, and previously uncontrolled nausea or vomiting. RESULTS: Acute CIN was associated with susceptibility to motion sickness (odds ratio [OR] 5.73, 95% confidence interval [CI] 1.36-33.7) and older age (OR 4.19, 95% CI 1.30-14.7), comparing age group 8-18 years with 0-3 years. Delayed CIN was associated with uncontrolled acute nausea or vomiting (OR 10.3, 95% CI 2.65-50.9), highly emetogenic chemotherapy (OR 8.26, 95% CI 1.17-76.8), and having a hematologic cancer type (OR 7.81, 95% CI 1.05-79.2). CONCLUSIONS: Susceptibility to motion sickness and age can influence the risk of acute CIN. More research is needed on how best to integrate risk information in preventive antiemetic strategies. Sufficient acute nausea and vomiting control are crucial to prevent delayed CIN.


Assuntos
Antieméticos , Antineoplásicos , Enjoo devido ao Movimento , Neoplasias , Criança , Humanos , Lactente , Pré-Escolar , Adolescente , Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Estudos Prospectivos , Náusea/prevenção & controle , Vômito/prevenção & controle , Neoplasias/tratamento farmacológico , Fatores de Risco , Enjoo devido ao Movimento/induzido quimicamente , Enjoo devido ao Movimento/tratamento farmacológico
4.
BJOG ; 127(10): 1217-1225, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32237024

RESUMO

OBJECTIVE: To study the effect of antenatal magnesium sulphate (MgSO4 ) on cerebral palsy (CP) in a manner that also provides adequate power for a linked trial sequential analysis. DESIGN: Double-blind, randomised, placebo-controlled, multi-centre trial. SETTING: Fourteen Danish obstetric departments. POPULATION: In total, 560 pregnant women at risk for preterm delivery before 32 weeks of gestation were randomised from December 2011 to January 2018. Those women gave birth to 680 children. METHODS: Women were randomised to receive either a loading dose of 5 g MgSO4 followed by 1 g/hour or a placebo in identical volumes. The children were followed up at a corrected age of 18 months or older with a review of their medical charts and with the Ages and Stages Questionnaire. MAIN OUTCOME MEASURE: The primary outcome measure was moderate to severe CP. Secondary outcomes included mortality, neonatal morbidity, blindness and mild CP. RESULTS: The crude rates of moderate to severe CP in the MgSO4 group and the placebo group were 2.0% and 3.3%, respectively. The adjusted odds of moderate to severe CP were lower in the MgSO4 group than in the placebo group (odds ratio 0.61; 95% CI 0.23-1.65). CONCLUSIONS: Antenatal MgSO4 before 32 weeks of gestation decreases the likelihood of moderate to severe CP; these results are entirely consistent with other randomised evidence summarised in the linked trial sequential analysis. TWEETABLE ABSTRACT: Antenatal magnesium sulphate may decrease the risk of moderate to severe cerebral palsy in children born before 32 weeks of gestation.


Assuntos
Paralisia Cerebral/prevenção & controle , Sulfato de Magnésio/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Nascimento Prematuro/tratamento farmacológico , Adulto , Dinamarca , Método Duplo-Cego , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Nascimento Prematuro/etiologia , Cuidado Pré-Natal/métodos , Índice de Gravidade de Doença
5.
BJOG ; 127(10): 1180-1188, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32237069

RESUMO

BACKGROUND: Ordinary meta-analyses indicate that magnesium sulphate (MgSO4 ) treatment in women at imminent risk for preterm delivery decreases the offspring's risk of cerebral palsy (CP). However, repetitive testing of cumulative data calls for statistical caution, e.g. by trial sequential analysis (TSA), for which there are previously insufficient samples to draw a firm conclusion. Recently, a randomised controlled trial (RCT) provided additional data that potentially increased the sample size such that a new TSA might detect a statistically significant effect. OBJECTIVES: To assess the possible fetal neuroprotective effect of MgSO4 for women at imminent risk for preterm delivery in an updated systematic review with meta-analysis and TSA. SEARCH STRATEGY: We searched MEDLINE, Embase, Cochrane and ClinicalTrials.gov on 8 October 2019. The search strategy clustered terms describing the MgSO4 intervention and preterm delivery. SELECTION CRITERIA: RCTs. DATA COLLECTION AND ANALYSIS: Two reviewers extracted the data. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using fixed-effects models. A TSA was applied to the primary outcome, CP. The quality of the evidence was assessed using GRADE. The protocol was registered in PROSPERO (registration: CRD42019151441). MAIN RESULTS: We identified six eligible trials (5917 women). MgSO4 intervention in women at imminent risk for preterm birth decreased the offspring's CP risk (meta-analysis RR 0.68, 95% CI 0.54-0.85; TSA RR 0.69, 95% CI 0.48-0.97). CONCLUSIONS: This systematic review with meta-analysis and TSA shows conclusively that MgSO4 , when given to women at imminent risk for preterm delivery, decreases the offspring's CP risk. TWEETABLE ABSTRACT: Antenatal magnesium sulphate decreases the risk of cerebral palsy in children born preterm.


Assuntos
Paralisia Cerebral/prevenção & controle , Sulfato de Magnésio/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Nascimento Prematuro/tratamento farmacológico , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Cuidado Pré-Natal/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Medição de Risco
6.
Eur J Cancer Care (Engl) ; 25(1): 170-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25204197

RESUMO

Increased survival rates from childhood cancer call for efforts to reintegrate children with cancer back into their academic and social environments. The aims of this study were to: (1) review and analyse the existing literature on school re-entry interventions for children with cancer; and (2) discuss the importance of peer involvement in the treatment. Relevant databases were searched using equivalent search algorithms and six studies were selected that target children with cancer and/or their classmates. Two authors independently reviewed the literature for data extraction. The articles were reviewed using the PRISMA model for reporting reviews. Statistical calculations for the meta-analyses were done using Review Manager 5.2. The meta-analyses showed significant effects of school re-entry programmes in terms of enhancing academic achievement in children with cancer (P = 0.008) and lowering their levels of depression (P = 0.05). Increased knowledge among classmates was associated with less fear and a more positive attitude towards the child with cancer. Due to limited numbers of patients, lack of control groups, and the diversity of intervention strategies used in previous studies, there is a need for intervention programmes exploring the optimal path for the reintegration of children with cancer into the education system and into their peer groups.


Assuntos
Neoplasias/reabilitação , Grupo Associado , Distância Psicológica , Serviços de Saúde Escolar , Adolescente , Criança , Pré-Escolar , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Neoplasias/psicologia , Adulto Jovem
7.
Acta Anaesthesiol Scand ; 55(10): 1174-89, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22092122

RESUMO

BACKGROUND: Thrombelastography (TEG) and Thrombelastometry (ROTEM) are viscoelastic whole-blood assays evaluating the haemostatic capacity of blood. These devices are used in algorithms to guide transfusion of haemostatic blood components. METHODS: The methods used for this study were systematic reviews with meta-analyses and trial sequential analyses of randomised clinical trials (RCTs) of TEG/ROTEM-based algorithm compared with standard treatment in patients with bleeding. Primary outcome was all-cause mortality. We searched the literature in seven databases (up to 31 October 2010), reference lists, registers of ongoing trials, and contacted authors and experts. We extracted data from included studies related to study methods, interventions, outcomes, bias risk and adverse events using Cochrane methodology. All trials irrespective of blinding or language status were included. RESULTS: Nine trials involving 776 participants were included. Eight trials involved cardiac surgery with an average blood loss of 390-960 ml, and one trial investigated liver transplantations. One trial was classified as low-risk-of-bias trial. We found two ongoing trials. No impact was identified on mortality, amount of blood transfused, incidence of surgical reinterventions, time to extubation, or length of stay in hospital and intensive care unit. We identified a significant reduction in blood loss favouring the use of TEG/ROTEM {85 ml [95% confidence interval (CI) 29.4-140.7]} and in the proportion of patients receiving freshly frozen plasma and platelets [relative risk 0.39 (95%CI 0.27-0.57)]. CONCLUSION: There is currently weak evidence to support the use of TEG/ROTEM as a tool to guide transfusion in patients with severe bleeding. Further studies need to address other clinical settings and with larger blood losses.


Assuntos
Monitorização Fisiológica/métodos , Tromboelastografia/métodos , Reação Transfusional , Algoritmos , Transfusão de Componentes Sanguíneos , Perda Sanguínea Cirúrgica/fisiopatologia , Transfusão de Sangue/mortalidade , Viscosidade Sanguínea , Procedimentos Cirúrgicos Cardíacos , Bases de Dados Factuais , Hemorragia/terapia , Hemostasia/fisiologia , Humanos , Transplante de Fígado , Plasma , Transfusão de Plaquetas , Ensaios Clínicos Controlados Aleatórios como Assunto , Tromboelastografia/mortalidade , Resultado do Tratamento
9.
Aliment Pharmacol Ther ; 32(7): 840-50, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20839385

RESUMO

BACKGROUND: Multiple randomized trials have been published on antiviral treatment for chronic hepatitis C. AIM: To meta-analyse the effect of adding ribavirin to interferon for chronic hepatitis C. METHODS: The results of randomized trials were combined in cumulative meta-analyses. Trial sequential analyses were used to adjust for spurious results because of random errors and multiplicity. The outcome measures were undetectable hepatitis C virus RNA in serum (sustained virological response) and liver-related morbidity plus all-cause mortality. RESULTS: We included 82 randomized trials with 12 615 patients. Trial sequential analysis established clear beneficial effect of interferon plus ribavirin vs. interferon on the sustained virological response in 1998 after nine trials (RR: 0.74; 95% CI: 0.64-0.85, P < 0.0001, 1734 patients). Subsequently, additional 73 trials were published just narrowing the confidence interval and decreasing the P-value. By contrast, trial sequential analysis found that additional evidence is needed to convincingly detect a beneficial effect of interferon plus ribavirin vs. interferon monotherapy on clinical outcomes. CONCLUSIONS: The rationale behind several recent trials on adding ribavirin to interferon for chronic hepatitis C is debatable as the effect on virological response is established. More evidence is needed to assess if adding ribavirin to interferon improves clinical outcomes.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estatística como Assunto , Resultado do Tratamento
10.
Phys Rev Lett ; 104(8): 083903, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20366932

RESUMO

Circularly polarized electric fields incident on subwavelength apertures produce near-field phase singularities with phase vorticity +/-1 depending on the polarization handedness. These near-field phase singularities combine with those associated with orbital angular momentum and result in polarization-dependent transmission. We produce arbitrary phase vorticity in the longitudinal component of scattered electric fields by varying the incident beam and aperture configuration.

11.
Opt Express ; 16(10): 7407-17, 2008 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-18545445

RESUMO

Using terahertz-light excitation, we have measured with sub-wavelength spatial, and sub-cycle temporal resolution the time- and frequency-dependent electric-field and surface-charge density in the vicinity of small metallic holes. In addition to a singularity like concentration of the electric field near the hole edges, we observe, that holes can act as differential operators whose near-field output is the time-derivative of the incident electric field. Our results confirm the well-known predictions made by Bouwkamp, Philips Res. Rep. 5, 321-332 (1950), and reveal, with unprecedented detail, what physically happens when light passes through a small hole.


Assuntos
Metais/química , Microscopia/métodos , Óptica e Fotônica , Espectrofotometria/métodos , Físico-Química/métodos , Eletricidade , Eletroquímica/métodos , Desenho de Equipamento , Modelos Estatísticos , Modelos Teóricos , Espalhamento de Radiação , Análise Espectral Raman , Fatores de Tempo
12.
Arch Dis Child Fetal Neonatal Ed ; 93(3): F225-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17893123

RESUMO

OBJECTIVE: To assess agreement between Cochrane Neonatal Group reviews and clinical practice guidelines in Denmark. DESIGN: Retrospective analysis of clinical guidelines for newborn infants. MATERIALS: All Cochrane neonatal reviews and Danish clinical guidelines for newborn infants. MAIN OUTCOME MEASURES: The recommendations from the Cochrane reviews and local clinical guidelines were compared and classified as being in agreement, in partial agreement or in disagreement. Authors of guidelines were asked whether Cochrane reviews had been considered during guideline development and reasons for any disagreements. Heterogeneity among departments was assessed. RESULTS: 173 interventions evaluated in Cochrane neonatal reviews were included. All 17 Danish neonatal departments agreed to participate, but only 14 (82%) delivered data. Agreement between reviews and guidelines was observed for a median of 132 interventions (76%) (range 129-134), partial agreement was observed for 31 interventions (18%) (range 29-33), and disagreement was observed for 10 interventions (6%) (range 8-13) (kappa = 0.56, range 0.53-0.59). Most of the latter 10 interventions were not recommended in the reviews but were recommended in the guidelines. There were numerous reasons for disagreement, the most common being usage of evidence with higher bias risks than randomised trials in guidelines development. Overall, Cochrane reviews were rarely (10%) used during guideline development. For nine guideline topics (5%) there was diversity among the Danish departments' recommendations. CONCLUSIONS: There is good agreement between Cochrane reviews and neonatal guidelines in Denmark. However, Cochrane reviews were rarely used for guideline development. Heterogeneity among guidelines produced by the various neonatal departments seems moderate.


Assuntos
Medicina Baseada em Evidências/métodos , Neonatologia/normas , Guias de Prática Clínica como Assunto/normas , Literatura de Revisão como Assunto , Estudos de Casos e Controles , Consenso , Dinamarca , Humanos , Recém-Nascido , Estudos Retrospectivos
13.
Aliment Pharmacol Ther ; 25(10): 1153-62, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17451561

RESUMO

BACKGROUND: About 170 million patients worldwide have chronic hepatitis C. Pegylated interferon plus ribavirin is currently the recommended therapy. AIM: To evaluate the beneficial and harmful effects of pegylated interferon plus ribavirin vs. interferon plus ribavirin for chronic hepatitis C infection. METHODS: We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, Science Citation Index Expanded and contacted pharmaceutical companies and authors of trials (to March 2005). RESULTS: We included 18 randomized clinical trials with 4811 patients. Eleven trials (61%) had allocation bias risks and all had assessment bias risk because of lack of blinding. Compared with interferon plus ribavirin, pegylated interferon plus ribavirin had significant beneficial effects on sustained virological response [risk ratio (RR): 0.80; 95% CI: 0.74-0.88]. Data were insufficient to determine impact on long-term outcomes. Pegylated interferon plus ribavirin significantly increased dose reductions (RR: 1.44; 95% CI: 1.14-1.82) and adverse events including neutropenia (RR: 2.25; 95% CI: 1.58-3.21), thrombocytopenia (RR: 2.28; 95% CI: 1.14-4.54), arthralgia (RR: 1.19; 95% CI: 1.05-1.35), and injection-site reaction (RR: 2.56; 95% CI: 1.06-6.22). CONCLUSIONS: Pegylated interferon plus ribavirin compared with interferon plus ribavirin increased the proportion of patients with sustained virological response, but at the cost of more adverse events.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Análise Custo-Benefício , Quimioterapia Combinada , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
14.
Cochrane Database Syst Rev ; (2): CD003328, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16625578

RESUMO

BACKGROUND: Poisoning with paracetamol (acetaminophen) is a common cause of hepatotoxicity in the Western World. Inhibition of absorption, removal from the vascular system, antidotes, and liver transplantation are interventions for paracetamol poisoning. OBJECTIVES: To assess the benefits and harms of interventions for paracetamol overdose. SEARCH STRATEGY: We identified trials through electronic databases, manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies until December 2005. SELECTION CRITERIA: Randomised clinical trials and observational studies were included. DATA COLLECTION AND ANALYSIS: The primary outcome measure was all-cause mortality plus liver transplantation. Secondary outcome measures were clinical symptoms, (eg, hepatic encephalopathy, fulminant hepatic failure), hepatotoxicity, adverse events, and plasma paracetamol concentration. We used Peto odds ratios and odds ratios with 95% confidence intervals (CI) for analysis of outcomes. Random- and fixed-effects meta-analyses were performed. MAIN RESULTS: Ten small and low-methodological quality randomised trials, one quasi-randomised study, and 48 observational studies were identified. It was not possible to perform relevant meta-analyses of randomised trials that have addressed our outcome measures. Activated charcoal, gastric lavage, and ipecacuanha are able to reduce the absorption of paracetamol, but the clinical benefit is unclear. Of these, activated charcoal seems to have the best risk-benefit ratio. N-acetylcysteine seems preferable to placebo/supportive treatment, dimercaprol, and cysteamine, but N-acetylcysteine's superiority to methionine is unproven. It is not clear which N-acetylcysteine treatment protocol offers the best efficacy. No strong evidence supports other interventions for paracetamol overdose. N-acetylcysteine may reduce mortality in patients with fulminant hepatic failure (Peto OR 0.26, 95% CI 0.09 to 0.94, one trial). Liver transplantation has the potential to be life saving in fulminant hepatic failure, but refinement of selection criteria for transplantation and long-term outcome reporting are required. AUTHORS' CONCLUSIONS: Our results highlight a paucity of randomised trials on interventions for paracetamol overdose. Activated charcoal seems the best choice to reduce absorption. N-acetylcysteine should be given to patients with overdose but the selection criteria are not clear. No N-acetylcysteine regime has been shown to be more effective than any other. It is a delicate balance when to proceed to liver transplantation, which may be life-saving for patients with poor prognosis.


Assuntos
Acetaminofen/intoxicação , Analgésicos não Narcóticos/intoxicação , Acetaminofen/farmacocinética , Analgésicos não Narcóticos/farmacocinética , Antídotos/uso terapêutico , Carvão Vegetal/uso terapêutico , Overdose de Drogas/terapia , Lavagem Gástrica , Humanos , Absorção Intestinal , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/cirurgia , Transplante de Fígado
15.
Cochrane Database Syst Rev ; (2): CD004790, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16625613

RESUMO

BACKGROUND: Hepatitis B vaccine and hepatitis B immunoglobulin are considered for newborn infants of HBsAg-positive mothers to prevent hepatitis B infection. OBJECTIVES: To assess the beneficial and harmful effects of hepatitis B vaccines and hepatitis B immunoglobulin in newborn infants of HBsAg-positive mothers. SEARCH STRATEGY: Trials were identified through The Cochrane Neonatal Group Controlled Trials Register, The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials in The Cochrane Library, MEDLINE, and EMBASE (until February 2004), authors of trials, and pharmaceutical companies. SELECTION CRITERIA: Randomised clinical trials comparing: plasma-derived vaccine (PDV) or recombinant vaccine (RV) versus no intervention, placebo, or other active vaccines; hepatitis B immunoglobulin versus no intervention, placebo, or other control immunoglobulin; as well as PDV or RV plus hepatitis B immunoglobulin versus no intervention, placebo, or other control vaccines or immunoglobulin. DATA COLLECTION AND ANALYSIS: Outcomes are assessed at maximal follow-up. The primary outcome measure was hepatitis B occurrence, based on a blood specimen positive for HBsAg, HBeAg, or antibody to hepatitis B core antigen (anti-HBc). Binary outcomes are reported as relative risks (RR) with 95% confidence interval (CI). Subgroup analyses were performed with regard to methodological quality of the trial, mother's HBe-Ag status, and time of immunisation after birth. MAIN RESULTS: We identified 29 randomised clinical trials, five of which were considered high quality. Only three trials reported inclusion of hepatitis B e-antigen negative mothers. Compared with placebo/no intervention, vaccine reduced hepatitis B occurrence (RR 0.28, 95% confidence interval (CI) 0.20 to 0.40, 4 trials). No significant differences of hepatitis B occurrence were found comparing recombinant vaccine (RV) versus plasma-derived vaccine (PDV) (RR 1.00, 95% CI 0.71 to 1.42, 4 trials) and high-dose versus low-dose vaccine (PDV: RR 0.97, 95% CI 0.55 to 1.68, 3 trials; RV: RR 0.78, 95% CI 0.31 to 1.94, 1 trial). Compared with placebo/no intervention, hepatitis B immunoglobulin or the combination of vaccine plus hepatitis B immunoglobulin reduced hepatitis B occurrence (hepatitis B immunoglobulin: RR 0.50, 95% CI 0.41 to 0.60, 1 trial; PDV plus hepatitis B immunoglobulin: RR 0.08, 95% CI 0.03 to 0.17, 3 trials). Compared with vaccine, vaccine plus hepatitis B immunoglobulin reduced hepatitis B occurrence (RR 0.54, 95% CI 0.41 to 0.73, 10 trials). Hepatitis B vaccine and hepatitis B immunoglobulin seem safe, but few trials reported on adverse events. AUTHORS' CONCLUSIONS: Vaccine, hepatitis B immunoglobulin, and vaccine plus hepatitis B immunoglobulin prevent hepatitis B occurrence in newborn infants of HBsAg positive mothers.


Assuntos
Anticorpos Anti-Hepatite B/uso terapêutico , Vacinas contra Hepatite B/uso terapêutico , Antígenos E da Hepatite B/sangue , Hepatite B/prevenção & controle , Feminino , Hepatite B/imunologia , Humanos , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Opt Express ; 14(7): 2552-72, 2006 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19516386

RESUMO

We discuss a mode expansion technique to rigorously model the diffraction from three-dimensional pits and holes in a perfectly conducting layer with finite thickness. On the basis of our simulations we predict extraordinary transmission through a single hole, caused by the Fabry-Perot effect inside the hole. Furthermore, we study the fundamental building block for extraordinary transmission through hole arrays: two and three holes. Coupled electromagnetic surface waves, the perfect conductor equivalent of a surface plasmon, are found to play a key role in the mutual interaction between two or three holes.

17.
Cochrane Database Syst Rev ; (4): CD005527, 2005 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16235408

RESUMO

BACKGROUND: Hepatitis C is a major cause of liver-related morbidity and mortality. The disease progresses without symptoms for several decades. Ribavirin monotherapy may represent a treatment for some patients. OBJECTIVES: To assess the beneficial and harmful effect of ribavirin monotherapy for patients with chronic hepatitis C. SEARCH STRATEGY: We identified trials through electronic databases, manual searches of bibliographies and journals, authors of trials, and pharmaceutical companies until May 2005. SELECTION CRITERIA: We included all randomised trials irrespective of blinding, language, or publication status comparing ribavirin versus no intervention, placebo, or interferon for chronic hepatitis C. DATA COLLECTION AND ANALYSIS: The primary outcome measures were the six months sustained loss of hepatitis C virus RNA in blood after end of treatment and liver-related morbidity plus all-cause mortality. Secondary outcome measures were end of treatment virological response, biochemical response, histological response, and adverse events. Random- and fixed-effects meta-analyses with 95% confidence intervals (CI) were performed for all outcomes. We used Peto odds ratios (OR) for analysis of morbidity plus mortality and relative risks (RR) for the remaining outcomes. MAIN RESULTS: We identified 13 randomised trials including 594 patients with chronic hepatitis C. Most trials had low methodological quality. Compared with placebo/no intervention, ribavirin had no significant effect on sustained (RR 1.01, 95% CI 0.96 to 1.07, five trials) or end of treatment virological response (RR 1.00, 95% CI 0.94 to 1.07, ten trials). Ribavirin had no significant effect on liver-related morbidity plus mortality (Peto OR 1.96, 95% CI 0.20 to 19.0, eleven trials). Ribavirin significantly improved end of treatment biochemical and histological response but not sustained biochemical response. Further, ribavirin significantly increased the risk of anaemia. Ribavirin was significantly inferior to interferon regarding virological and biochemical response (four trials). AUTHORS' CONCLUSIONS: We found that ribavirin versus placebo/no intervention had no significant beneficial effect on virological response and liver morbidity, but may improve biochemical and histological response transiently. Ribavirin increased the risk of anaemia. Therefore, we cannot recommend ribavirin monotherapy for patients with chronic hepatitis C outside randomised trials.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Ribavirina/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Cochrane Database Syst Rev ; (3): CD005445, 2005 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16034976

RESUMO

BACKGROUND: Hepatitis C is a major cause of liver-related morbidity and mortality. The disease progresses without symptoms for several decades and most patients are diagnosed based on the presence of hepatitis C virus ribonucleic acid and elevated transaminases. OBJECTIVES: To assess the beneficial and harmful effects of ribavirin and interferon combination therapy versus interferon monotherapy for chronic hepatitis C. SEARCH STRATEGY: We identified trials through electronic databases, manual searches of bibliographies and journals, approaching authors of trials and pharmaceutical companies, until May 2004. SELECTION CRITERIA: We included randomised trials, irrespective of blinding, language, or publication status, comparing ribavirin plus interferon versus interferon alone for treatment of chronic hepatitis C. DATA COLLECTION AND ANALYSIS: The primary outcome measures were the sustained loss of hepatitis C virus and liver-related morbidity plus all-cause mortality. We separately analysed patients who were naive, relapsers, or non-responders to previous antiviral treatment. Random-effects and fixed-effect model meta-analyses were performed for all outcomes. We used Peto odds ratios (OR) with 95% confidence intervals (CI) for analysis of morbidity plus mortality. The remaining outcomes were presented as relative risks (RR). MAIN RESULTS: We included 72 randomised trials with 9991 patients. Most trials had low methodological quality but we did not find any significant influence of quality on our results. Compared with interferon, combination therapy had a significant beneficial effect on sustained virological response (RR 0.73, 95% CI 0.71 to 0.75) and in subgroups of naive patients (RR 0.72, 95% CI 0.68 to 0.76), relapsers (RR 0.63, 95% CI 0.54 to 0.73), and non-responders (RR 0.89, 95% CI 0.84 to 0.94) individually. Combination therapy significantly reduced morbidity plus mortality (Peto OR 0.46, 95% CI 0.22 to 0.96), but not in naive, relapsers, or non-responders individually. Combination therapy also had a significant beneficial effect on the histological response. Combination therapy significantly increased the risk of anaemia (RR 10.48, 95% CI 5.34 to 20.55), which occurred in 22% of patients on combination therapy. Combination therapy also significantly increased the risk of dermatological, gastrointestinal, infectious, and miscellaneous (cough, dyspnea, fatigue) adverse events. Accordingly, combination therapy significantly increased the risk of treatment discontinuation (RR 1.19, 95% CI 1.01 to 1.39). AUTHORS' CONCLUSIONS: Compared with interferon alone, ribavirin plus interferon is more effective in clearing hepatitis C virus and improving liver histology. This may lead to reduced morbidity and mortality. However, combination therapy significantly increased the risk of several adverse events.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ribavirina/uso terapêutico , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Cochrane Database Syst Rev ; (2): CD002904, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15106184

RESUMO

BACKGROUND: Hepatitis C virus may cause liver inflammation and fibrosis. It is not known whether glucocorticosteroids are beneficial or harmful for patients with hepatitis C infection. OBJECTIVES: The objectives were to evaluate the beneficial and harmful effects of glucocorticosteroids for patients with acute or chronic hepatitis C infection with or without hepatitis C related autoimmune disorders. SEARCH STRATEGY: Searches of The Cochrane Hepato-Biliary Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and reference lists of relevant articles and hand searches of relevant journals were performed in July 2003. Principal authors of clinical trials were approached. SELECTION CRITERIA: Randomised clinical trials dealing with glucocorticosteroids for viral hepatitis C - acute or chronic with or without autoimmune disorders. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer and validated by another. Further information was sought by correspondence with the principal investigator of the trial in case the relevant data were not published. Disagreements were solved by discussion before the meta-analysis. MAIN RESULTS: Eight trials randomised 384 patients with chronic hepatitis C to glucocorticosteroids plus interferon versus interferon plus placebo/no intervention, glucocorticosteroids versus interferon, or glucocorticosteroids versus placebo. Glucocorticosteroids treatment given as short pre-treatment followed by interferon or as long-term parallel treatment combined with interferon versus interferon monotherapy had no significant effect on mortality (no deaths occurred; 342 patients), virological response at six months follow-up (RR 0.85; 95% CI 0.52 to 1.38; 38 patients), or biochemical response at six months follow-up (RR 0.95; 95% CI 0.84 to 1.06; 307 patients). There was no significant difference in serious adverse events between combination therapy versus interferon monotherapy (RR 4.76; 95% CI 0.24 to 93.19; 342 patients). Glucocorticosteroids versus interferon had no significant effect on mortality (RR 2.33; 95% CI 0.27 to 17.80; 13 patients) or virological response at follow-up (RR 1.17; 95% CI 0.86 to 1.58; 13 patients). We found no trials on glucocorticosteroids for acute hepatitis C. REVIEWERS' CONCLUSIONS: There is insufficient evidence neither to confirm nor exclude both beneficial and harmful effects of glucocorticosteroids for chronic hepatitis C with or without autoimmune disorders. This Review is not able to rule out potential serious adverse effects of glucocorticosteroids. Therefore, this Review cannot establish whether glucocorticosteroids treatment can be safely administrated for indications requiring glucocorticosteroids without analysing for hepatitis C virus. The effect of glucocorticosteroids for acute hepatitis C has not been examined in randomised trials.


Assuntos
Glucocorticoides/uso terapêutico , Hepatite C/tratamento farmacológico , Doença Aguda , Antivirais/uso terapêutico , Quimioterapia Combinada , Glucocorticoides/efeitos adversos , Hepatite C/mortalidade , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/mortalidade , Humanos , Interferons/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
J Opt Soc Am A Opt Image Sci Vis ; 20(2): 256-72, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12570292

RESUMO

We describe a rigorous model for the scattering of a three-dimensional focused spot by a one-dimensional periodic grating. The incident field is decomposed into a sum of quasi-periodic fields, and the scattering of each of these is computed inside one unit cell of the grating. The model is applied to the simulation of the readout of a DVD disk. The polarization dependence of the reflected near and far fields is studied, and, for a TM-polarized incident spot, plasmons are observed in the reflected far-field intensity.

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