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1.
AJNR Am J Neuroradiol ; 41(6): 994-1000, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32499250

RESUMO

BACKGROUND AND PURPOSE: Whiplash-associated disorders frequently develop following motor vehicle collisions and often involve a range of cognitive and affective symptoms, though the neural correlates of the disorder are largely unknown. In this study, a sample of participants with chronic whiplash injuries were scanned by using resting-state fMRI to assess brain network changes associated with long-term outcome metrics. MATERIALS AND METHODS: Resting-state fMRI was collected for 23 participants and used to calculate network modularity, a quantitative measure of the functional segregation of brain region communities. This was analyzed for associations with whiplash-associated disorder outcome metrics, including scales of neck disability, traumatic distress, depression, and pain. In addition to these clinical scales, cervical muscle fat infiltration was quantified by using Dixon fat-water imaging, which has shown promise as a biomarker for assessing disorder severity and predicting recovery in chronic whiplash. RESULTS: An association was found between brain network structure and muscle fat infiltration, wherein lower network modularity was associated with larger amounts of cervical muscle fat infiltration after controlling for age, sex, body mass index, and scan motion (t = -4.02, partial R 2 = 0.49, P < .001). CONCLUSIONS: This work contributes to the existing whiplash literature by examining a sample of participants with whiplash-associated disorder by using resting-state fMRI. Less modular brain networks were found to be associated with greater amounts of cervical muscle fat infiltration suggesting a connection between disorder severity and neurologic changes, and a potential role for neuroimaging in understanding the pathophysiology of chronic whiplash-associated disorders.


Assuntos
Músculos do Pescoço/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Traumatismos em Chicotada/fisiopatologia , Acidentes de Trânsito , Tecido Adiposo/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/diagnóstico por imagem , Traumatismos em Chicotada/diagnóstico por imagem
2.
J R Stat Soc Ser A Stat Soc ; 183(1): 193-209, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31857745

RESUMO

Flaws in the conduct of randomized trials can lead to biased estimation of the intervention effect. Methods for adjustment of within-trial biases in meta-analysis include the use of empirical evidence from an external collection of meta-analyses, and the use of expert opinion informed by the assessment of detailed trial information. Our aim is to present methods to combine these two approaches to gain the advantages of both. We make use of the risk of bias information that is routinely available in Cochrane reviews, by obtaining empirical distributions for the bias associated with particular bias profiles (combinations of risk of bias judgements). We propose three methods: a formal combination of empirical evidence and opinion in a Bayesian analysis; asking experts to give an opinion on bias informed by both summary trial information and a bias distribution from the empirical evidence, either numerically or by selecting areas of the empirical distribution. The methods are demonstrated through application to two example binary outcome meta-analyses. Bias distributions based on opinion informed by trial information alone were most dispersed on average, and those based on opinions obtained by selecting areas of the empirical distribution were narrowest. Although the three methods for combining empirical evidence with opinion vary in ease and speed of implementation, they yielded similar results in the two examples.

3.
Stat Med ; 37(1): 60-70, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28929507

RESUMO

Rich meta-epidemiological data sets have been collected to explore associations between intervention effect estimates and study-level characteristics. Welton et al proposed models for the analysis of meta-epidemiological data, but these models are restrictive because they force heterogeneity among studies with a particular characteristic to be at least as large as that among studies without the characteristic. In this paper we present alternative models that are invariant to the labels defining the 2 categories of studies. To exemplify the methods, we use a collection of meta-analyses in which the Cochrane Risk of Bias tool has been implemented. We first investigate the influence of small trial sample sizes (less than 100 participants), before investigating the influence of multiple methodological flaws (inadequate or unclear sequence generation, allocation concealment, and blinding). We fit both the Welton et al model and our proposed label-invariant model and compare the results. Estimates of mean bias associated with the trial characteristics and of between-trial variances are not very sensitive to the choice of model. Results from fitting a univariable model show that heterogeneity variance is, on average, 88% greater among trials with less than 100 participants. On the basis of a multivariable model, heterogeneity variance is, on average, 25% greater among trials with inadequate/unclear sequence generation, 51% greater among trials with inadequate/unclear blinding, and 23% lower among trials with inadequate/unclear allocation concealment, although the 95% intervals for these ratios are very wide. Our proposed label-invariant models for meta-epidemiological data analysis facilitate investigations of between-study heterogeneity attributable to certain study characteristics.


Assuntos
Interpretação Estatística de Dados , Estudos Epidemiológicos , Metanálise como Assunto , Modelos Estatísticos , Viés , Bioestatística/métodos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Humanos , Análise Multivariada , Tamanho da Amostra
4.
Bone Joint J ; 99-B(1): 94-99, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28053263

RESUMO

AIMS: Our purpose was to determine the quality of current randomised controlled trials (RCTs) in hand surgery using standardised metrics. MATERIALS AND METHODS: Based on five-year mean impact factors, we selected the six journals that routinely publish studies of upper extremity surgery. Using a journal-specific search query, 62 RCTs met our inclusion criteria. Then three blinded reviewers used the Jadad and revised Coleman Methodology Score (RCMS) to assess the quality of the manuscripts. RESULTS: Based on the Jadad scale, 28 studies were of high quality and 34 were of low quality. Methodological deficiencies in poorly scoring trials included the absence of rate of enrolment, no power analysis, no description of withdrawal or dropout, and a failure to use validated outcomes assessments with an independent investigator. CONCLUSION: A large number of RCTs in hand, wrist, and elbow surgery were of suboptimal quality when judged against the RCMS and Jadad scales. Even with a high level of evidence, study design and execution of RCTs should be critically assessed. Methodological deficiencies may introduce bias and lead to statistically underpowered studies. Cite this article: Bone Joint J 2017;99-B:94-9.


Assuntos
Articulação do Cotovelo/cirurgia , Mãos/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Punho/cirurgia , Análise de Variância , Humanos , Variações Dependentes do Observador , Procedimentos Ortopédicos/normas , Publicações Periódicas como Assunto/normas , Resultado do Tratamento
5.
J Hosp Infect ; 95(1): 3-45, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27890334

RESUMO

BACKGROUND: In recent years, infections with carbapenemase-producing Enterobacteriaceae (CPE) have been increasing globally and present a major public health challenge. AIM: To review the international literature: (i) to describe CPE outbreaks in acute hospital settings globally; and (ii) to identify the control measures used during these outbreaks and report on their effectiveness. METHODS: A systematic search of MEDLINE and EMBASE databases, abstract lists for key conferences and reference lists of key reviews was undertaken, and information on unpublished outbreaks was sought for 2000-2015. Where relevant, risk of bias was assessed using the Newcastle-Ottawa scale. A narrative synthesis of the evidence was conducted. FINDINGS: Ninety-eight outbreaks were eligible. These occurred worldwide, with 53 reports from Europe. The number of cases (CPE infection or colonization) involved in outbreaks varied widely, from two to 803. In the vast majority of outbreaks, multi-component infection control measures were used, commonly including: patient screening; contact precautions (e.g. gowns, gloves); handwashing interventions; staff education or monitoring; enhanced environmental cleaning/decontamination; cohorting of patients and/or staff; and patient isolation. Seven studies were identified as providing the best-available evidence on the effectiveness of control measures. These demonstrated that CPE outbreaks can be controlled successfully using a range of appropriate, commonly used, infection control measures. However, risk of bias was considered relatively high for these studies. CONCLUSION: The findings indicate that CPE outbreaks can be controlled using combinations of existing measures. However, the quality of the evidence base is weak and further high-quality research is needed, particularly on the effectiveness of individual infection control measures.


Assuntos
Proteínas de Bactérias/metabolismo , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/enzimologia , Controle de Infecções/métodos , beta-Lactamases/metabolismo , Cuidados Críticos , Infecção Hospitalar/prevenção & controle , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/prevenção & controle , Saúde Global , Humanos
6.
Aliment Pharmacol Ther ; 44(8): 785-95, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27534608

RESUMO

BACKGROUND: It is uncertain whether concurrent use of low-dose aspirin removes the gastrointestinal benefit displayed by COX-2 selective inhibitors (coxibs) when compared to traditional nonsteroidal anti-inflammatory drugs (NSAIDs). AIM: To evaluate the gastrointestinal risks associated with coxibs and traditional NSAIDs and the interaction with concurrent use of low-dose aspirin. METHODS: We searched MEDLINE, EMBASE and the Cochrane Library through April 2016 to identify randomised trials comparing the gastrointestinal risk between coxibs and traditional NSAIDs in patients taking or not taking low-dose aspirin. Results were combined using random effects meta-analysis. Subgroup analyses by concurrent use of aspirin were undertaken. RESULTS: Eleven trials (84 150 participants) were included. The overall relative risk (RR) of coxibs vs. traditional NSAIDs for complicated gastrointestinal events was 0.54 (95% CI, confidence interval 0.32-0.92), with a significant subgroup difference (P = 0.04) according to concurrent use of aspirin (used: RR = 0.96, 95% CI 0.66-1.24; not used: RR = 0.33, 95% CI 0.14-0.83). The overall RR for clinical gastrointestinal events was 0.59 (95% CI 0.47-0.75), with a significant subgroup difference according to aspirin usage (P = 0.008; used: RR = 0.77, 95% CI 0.62-0.95; not used: RR = 0.50, 95% CI 0.39-0.64). Overall coxibs were associated with significantly lower risk of symptomatic ulcers (RR = 0.60, 95% CI 0.50-0.72) and endoscopic ulcers (RR = 0.29, 95% CI 0.16-0.53) than traditional NSAIDs; a significant subgroup difference was shown for endoscopic ulcers (P = 0.05) but not for symptomatic ulcers (P = 0.27). CONCLUSION: Concomitant use of low-dose aspirin reduces but does not completely eliminate the gastrointestinal benefit of coxibs over traditional NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Gastroenteropatias/epidemiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Transpl Infect Dis ; 17(2): 275-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25641426

RESUMO

We report safety, tolerability, and 12-week sustained virologic response with half-standard dose sofosbuvir and standard-dose simeprevir combination therapy in a hepatitis C virus genotype 1a-infected liver transplant recipient on hemodialysis - uncharted territory for sofosbuvir-based therapy. The patient was a non-responder to prior treatment with pegylated interferon plus ribavirin. Sofosbuvir efficacy was maintained despite pill-splitting and administration of half-standard dose, 200 mg per day. No drug-drug interactions were noted with tacrolimus-based immunosuppression. Laboratory tests remained stable or improved during therapy. Our observation, if reproduced in a larger study, may lead to significant improvement in clinical outcomes and cost savings in this patient population.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Falência Renal Crônica/terapia , Transplante de Fígado , Simeprevir/uso terapêutico , Sofosbuvir/uso terapêutico , Quimioterapia Combinada , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Diálise Renal , Transplantados , Resultado do Tratamento , Carga Viral
8.
Crit Rev Food Sci Nutr ; 55(7): 1026-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25191830

RESUMO

Food and feed safety risk assessment uses multi-parameter models to evaluate the likelihood of adverse events associated with exposure to hazards in human health, plant health, animal health, animal welfare, and the environment. Systematic review and meta-analysis are established methods for answering questions in health care, and can be implemented to minimize biases in food and feed safety risk assessment. However, no methodological frameworks exist for refining risk assessment multi-parameter models into questions suitable for systematic review, and use of meta-analysis to estimate all parameters required by a risk model may not be always feasible. This paper describes novel approaches for determining question suitability and for prioritizing questions for systematic review in this area. Risk assessment questions that aim to estimate a parameter are likely to be suitable for systematic review. Such questions can be structured by their "key elements" [e.g., for intervention questions, the population(s), intervention(s), comparator(s), and outcome(s)]. Prioritization of questions to be addressed by systematic review relies on the likely impact and related uncertainty of individual parameters in the risk model. This approach to planning and prioritizing systematic review seems to have useful implications for producing evidence-based food and feed safety risk assessment.


Assuntos
Meio Ambiente , Inocuidade dos Alimentos , Alimentos , Valor Nutritivo , Ração Animal/efeitos adversos , Bem-Estar do Animal/normas , Animais , Manipulação de Alimentos/métodos , Humanos , Plantas , Medição de Risco , Toxicologia
12.
J Hand Surg Eur Vol ; 38(4): 352-65, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23186864

RESUMO

Reconstruction of digital defects using the venous flap offer several advantages but remained unpopular owing to levels of venous congestion rates. We performed animal studies to test the hypothesis that an arterio-venous shunt increases pressure for peripheral flap perfusion and decreases venous congestion. Using an abdominal adipofascial flap model in six male Sprague-Dawley rats, microcirculation was modified as follows: type I - arterial flap; type II - flow-through arterio-venous flap (AVF); and type III - shunt-restricted AVF. In type I flaps, blood flow was observed to be unidirectional in both arterioles and venules. In type I flaps, blood flow was observed to be unidirectional in both arterioles and venules. In type II flaps, blood flow oscillated without a dominant direction and came to a standstill. In type III flaps, blood flowed proximally in a reverse direction whereas distally, flow was similar to type I flaps. In a clinical series, 21 patients received a total of 22 shunt-restricted AVFs. All 22 clinical flaps survived; four flaps suffered epidermolysis but recovered without full thickness loss.


Assuntos
Traumatismos dos Dedos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Adolescente , Adulto , Animais , Fáscia/transplante , Feminino , Antebraço , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/fisiologia , Transplante de Pele , Resultado do Tratamento , Cicatrização/fisiologia
13.
Res Synth Methods ; 3(2): 98-110, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26062084

RESUMO

Meta-analyses that simultaneously compare multiple treatments (usually referred to as network meta-analyses or mixed treatment comparisons) are becoming increasingly common. An important component of a network meta-analysis is an assessment of the extent to which different sources of evidence are compatible, both substantively and statistically. A simple indirect comparison may be confounded if the studies involving one of the treatments of interest are fundamentally different from the studies involving the other treatment of interest. Here, we discuss methods for addressing inconsistency of evidence from comparative studies of different treatments. We define and review basic concepts of heterogeneity and inconsistency, and attempt to introduce a distinction between 'loop inconsistency' and 'design inconsistency'. We then propose that the notion of design-by-treatment interaction provides a useful general framework for investigating inconsistency. In particular, using design-by-treatment interactions successfully addresses complications that arise from the presence of multi-arm trials in an evidence network. We show how the inconsistency model proposed by Lu and Ades is a restricted version of our full design-by-treatment interaction model and that there may be several distinct Lu-Ades models for any particular data set. We introduce novel graphical methods for depicting networks of evidence, clearly depicting multi-arm trials and illustrating where there is potential for inconsistency to arise. We apply various inconsistency models to data from trials of different comparisons among four smoking cessation interventions and show that models seeking to address loop inconsistency alone can run into problems. Copyright © 2012 John Wiley & Sons, Ltd.

14.
Lancet ; 375(9722): 1267-77, 2010 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-20338627

RESUMO

BACKGROUND: Many randomised controlled trials have investigated the effect of adjuvant chemotherapy in operable non-small-cell lung cancer. We undertook two comprehensive systematic reviews and meta-analyses to establish the effects of adding adjuvant chemotherapy to surgery, or to surgery plus radiotherapy. METHODS: We included randomised trials, not confounded by additional therapeutic differences between the two groups and that started randomisation on or after Jan 1, 1965, which compared surgery plus adjuvant chemotherapy versus surgery alone, or surgery plus adjuvant radiotherapy and chemotherapy versus surgery plus adjuvant radiotherapy. Updated individual patient data were collected, checked, and included in meta-analyses stratified by trial. The primary endpoint was overall survival, defined as time from randomisation until death by any cause. All analyses were by intention to treat. FINDINGS: The first meta-analysis of surgery plus chemotherapy versus surgery alone was based on 34 trial comparisons and 8447 patients (3323 deaths). We recorded a benefit of adding chemotherapy after surgery (hazard ratio [HR] 0.86, 95% CI 0.81-0.92, p<0.0001), with an absolute increase in survival of 4% (95% CI 3-6) at 5 years (from 60% to 64%). The second meta-analysis of surgery plus radiotherapy and chemotherapy versus surgery plus radiotherapy was based on 13 trial comparisons and 2660 patients (1909 deaths). We recorded a benefit of adding chemotherapy to surgery plus radiotherapy (HR 0.88, 95% CI 0.81-0.97, p=0.009), representing an absolute improvement in survival of 4% (95% CI 1-8) at 5 years (from 29% to 33%). In both meta-analyses we noted little variation in effect according to the type of chemotherapy, other trial characteristics, or patient subgroup. INTERPRETATION: The addition of adjuvant chemotherapy after surgery for patients with operable non-small-cell lung cancer improves survival, irrespective of whether chemotherapy was adjuvant to surgery alone or adjuvant to surgery plus radiotherapy. FUNDING: UK Medical Research Council, Institut Gustave-Roussy, Programme Hospitalier de Recherche Clinique (AOM 05 209), Ligue Nationale Contre le Cancer, and Sanofi-Aventis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Quimioterapia Adjuvante , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida
15.
Poult Sci ; 89(2): 243-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20075275

RESUMO

In the present study, a series of experiments were conducted to evaluate the ability of a combination of 3 ATCC lactobacilli (LAB3) or a commercially available probiotic culture (PROB) to reduce Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) in broiler chicks. Additionally, we varied the timing of PROB administration in relationship to Salmonella challenge and determined the influence on recovery of enteric Salmonella. In experiments 1 to 3, chicks were randomly assigned to treatment groups and were then challenged via oral gavage with Salmonella Enteritidis. Chicks were treated 1 h after Salmonella Enteritidis challenge with LAB3 or PROB. Twenty-four hours posttreatment, cecal tonsils were collected for recovery of enteric Salmonella. In experiments 4 to 7, day-of-hatch chicks were randomly assigned to treatment groups and were then treated with PROB via oral gavage and placed into pens. Chicks were challenged with Salmonella Enteritidis 24 h after treatment via oral gavage. At 24 h after Salmonella Enteritidis challenge, cecal tonsils were collected and recovery of enteric Salmonella was determined. In experiments 8 to 10, 1-d-old chicks were randomly assigned to treatment groups and were then challenged via oral gavage with Salmonella Enteritidis and placed into pens. Chicks were treated 24 h after challenge with PROB via oral gavage. Twenty-four hours post PROB treatment, cecal tonsils were collected and enriched as described above. It was found that PROB significantly reduced cecal Salmonella Enteritidis recovery 24 h after treatment as compared with controls or LAB3-treated chicks in experiments 1 to 3 (P<0.05). Administration of PROB 24 h before Salmonella Enteritidis challenge significantly reduced recovery of Salmonella Enteritidis in 2 out of 4 experiments and no reduction in cecal Salmonella Enteritidis was observed when chicks were challenged with Salmonella Enteritidis and treated 24 h later with PROB. These data demonstrate that PROB more effectively reduced Salmonella Enteritidis than LAB3, and the timing of PROB treatment affects Salmonella Enteritidis-associated reductions.


Assuntos
Galinhas , Lactobacillus , Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Salmonelose Animal/prevenção & controle , Salmonella enteritidis , Ração Animal , Animais , Animais Recém-Nascidos , Dieta/veterinária , Esquema de Medicação , Masculino , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia
16.
Poult Sci ; 88(1): 57-60, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19096057

RESUMO

Beak trimming is necessary in commercial broiler breeders to prevent or decrease trauma as they mature. Two common beak-trimming methods were evaluated by early performance comparison with nontrimmed chicks (NBT). The robotic electrocautery device (ECD) trims and cauterizes the beak tip. The robotic infrared beak-trimming device (IBT) applies an infrared light beam to destroy the live basal tissue while leaving the hard corneum intact for the first approximately 10 d. In 2 experiments, day-of-hatch Ross 708 by-product chicks were obtained from a local hatchery, where 1/3 of the chicks were trimmed using IBT. All chicks were then transported to another hatchery where 1/3 were trimmed using ECD and 1/3 were NBT. Personnel at each hatchery were highly experienced and skilled with their respective technique. All chicks were then transported to University of Arkansas facilities. Before placement in each experiment, chicks were individually neck-tagged and weighed, and in experiment 1, beaks were measured using a digital caliper. A small but significant transient reduction in BW gain was observed at 14 d due to ECD as compared with NBT controls, although ECD was not different than IBT in experiment 1. In experiment 2, IBT birds were significantly heavier at 11 d by 7.8 and 8.7 g than the NBT or ECD, respectively. However, at d 21 and 42, no significant differences in BW or BW gain were observed. When beak trimming was performed on day of hatch by skilled and experienced personnel, little measurable effect on early performance was observed during the first 6 wk of life. Decreased broiler performance is generally considered a sensitive indication of physical or psychogenic stress. Given the marked reduction in beak-inflicted trauma with beak trimming birds as they reach sexual maturity, these results suggest that when properly performed, neither of these beak-trimming methods causes sufficient physical or psychogenic stress to markedly affect early growth rate.


Assuntos
Criação de Animais Domésticos/métodos , Bico/cirurgia , Galinhas/crescimento & desenvolvimento , Animais , Eletrocoagulação/efeitos adversos , Eletrocoagulação/veterinária , Feminino , Lasers/efeitos adversos , Aumento de Peso
17.
Avian Dis ; 52(1): 139-42, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18459311

RESUMO

Because of recent interest in bacteriophage therapy in poultry, information regarding the interaction of bacteriophages and potential host bacteria in the environment should be collected. The present studies were initiated with a rather typical commercial broiler integrator within the south-central United States to examine environmental Salmonella levels in two broiler complexes, attempt to isolate Salmonella-lytic bacteriophages, and elucidate a possible reason for differing apparent Salmonella prevalence. Significantly (P < 0.05) less Salmonella was isolated from houses in complex 1 (15/44 [34%] Salmonella-positive drag swabs) as compared to houses in complex 2 (22/24 [92%]). A total of seven Salmonella-lytic bacteriophages were isolated from Salmonella-positive environments, and two bacteriophages were isolated from a single Salmonella-negative house. During the initial bacteriophage isolation, individual bacteriophages did not replicate in the Salmonella host isolated from the same environment, and lysis of additional Salmonella hosts relied on high numbers of bacteriophage to be present. This suggests that the presence of these bacteriophages in the environment of a commercial broiler house had little to no effect on the presence of Salmonella. This study highlights the need to find additional bacteriophage sources, more effective isolation methods, and more innovative approaches to using bacteriophages to treat enteric disease.


Assuntos
Galinhas/microbiologia , Abrigo para Animais , Fagos de Salmonella/patogenicidade , Salmonella/virologia , Animais
18.
Am J Epidemiol ; 167(7): 759-74, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18270371

RESUMO

Multiple genes have been studied for potential associations with lung cancer. The gene most frequently associated with increased risk has been glutathione S-transferase M1 (GSTM1). The glutathione S-transferase enzyme family is known to catalyze detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins, and products of oxidative stress. In this review, the authors summarize the available evidence associating lung cancer with the GSTM1 gene. They describe results from an updated meta-analysis of 98 published genetic association studies investigating the relation between the GSTM1 null variant and lung cancer risk including 19,638 lung cancer cases and 25,266 controls (counting cases and controls in each study only once). All studies considered, the GSTM1 null variant was associated with an increased risk of lung cancer (odds ratio (OR) = 1.22, 95% confidence interval (CI): 1.14, 1.30), but no increase in risk was seen (OR = 1.01, 95% CI: 0.91, 1.12) when only the five largest studies (>500 cases each) were considered. Furthermore, while GSTM1 null status conferred a significantly increased risk of lung cancer to East Asians (OR = 1.38, 95% CI: 1.24, 1.55), such a genotype did not confer increased risk to Caucasians. More data regarding the predictive value of GSTM1 genetic testing are needed before population-based testing may be reasonably considered.


Assuntos
Glutationa Transferase/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Polimorfismo Genético , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Pulmonares/epidemiologia , Fatores de Risco
19.
Poult Sci ; 87(1): 27-31, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079446

RESUMO

We evaluated the effect of a Lactobacillus-based probiotic culture (FM-B11) for reduction of Salmonella Enteritidis in neonatal broiler chicks. In all experiments, chicks were challenged with approximately 10(4) cfu of Salmonella Enteritidis upon arrival at our laboratory, and the treatments were administered 1 h postchallenge. Cecal tonsil samples were obtained 24 h posttreatment and enriched for Salmonella Enteritidis recovery. The first experiment compared the effects of oral administration of doses of 10(4), 10(6), and 10(8) cfu/chick. In this experiment, doses of 10(6) and 10(8) both significantly reduced Salmonella Enteritidis recovery compared with controls (15 vs. 85% Salmonella Enteritidis positive), but 10(4) cfu did not significantly reduce Salmonella Enteritidis recovery. The second experiment compared the efficacy of oral administration of the live probiotic culture, with or without supernatant removed, to inactivated cultures or supernatant alone. Live probiotic organisms, with or without supernatant, significantly reduced Salmonella Enteritidis in this experiment, but inactivated or cell-free treatments did not reduce Salmonella Enteritidis. In the final 2 experiments, differing doses of probiotic culture were administered on the vent lips, where the treatment was taken into the lower gastrointestinal tract via cloacal drinking. Concentrations of probiotic culture from 10(2) to 10(7) cfu/chick significantly reduced Salmonella Enteritidis, and there was no difference in Salmonella Enteritidis recovery between treatment concentrations. These data suggest that this Lactobacillus-based probiotic culture may be efficacious for reduction of Salmonella Enteritidis in neonatal chicks.


Assuntos
Galinhas , Lactobacillus , Doenças das Aves Domésticas/terapia , Probióticos/farmacologia , Salmonelose Animal/terapia , Salmonella enteritidis/crescimento & desenvolvimento , Animais , Ceco/microbiologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle
20.
Ann Rheum Dis ; 67(5): 584-91, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17720722

RESUMO

UNLABELLED: We conducted a systematic review of genetic association studies for osteoarthritis of the peripheral joints (OA) and spinal degenerative disease (SDD). Electronic searches were carried out for any English language article reporting on a gene association study for either OA or SDD published up until the end of 2006. A team of seven reviewers used a standardised template to extract data in duplicate. In all, 90 studies fulfilled our inclusion criteria, reporting a total of 94 significant associations from 83 different genes. We found relatively few instances in which a specific gene-disease association had been analysed by more than one study, and there were 14 cases in which significant associations were replicated in independent studies (at joints associated with the AGC1, ASPN, COL9A2, COL9A3, COL11A2, ESR1, FZRB, HFE, IL1A, IL1RN, PTGS2 and VDR genes). METHOD: logical and reporting problems were widespread, including failure to report full results, missing population details, multiple testing, and over-reliance on subgroup analysis. In summary, the complex phenotypes of OA and SDD may have made it difficult for researchers to focus their efforts. The field is dominated by isolated analyses of disparate potential associations, a problem that is amplified by the frequent analysis of different polymorphisms within individual genes. Flaws in study methodology and interpretation undoubtedly increase the risk of publication bias. Closer adherence to published recommendations (in particular those produced by HuGENet) will help to ensure that future studies are well-designed and build on current understanding, rather than simply adding to the growing bank of potential associations.


Assuntos
Osteoartrite/genética , Osteofitose Vertebral/genética , Predisposição Genética para Doença , Genótipo , Humanos , Estudos de Amostragem
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