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1.
J Pain ; 25(7): 104468, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38219851

RESUMO

The measurement of withdrawal to experimenter-delivered mechanical stimuli (von Frey test) and to heat stimuli (radiant heat paw-withdrawal or Hargreaves' test) applied to the hind paws is ubiquitous in preclinical pain research, but no normative values for the most-common applications of these tests have ever been published. We analyzed a retrospective data set of withdrawal thresholds or latencies in 8,150 mice in which these measures were taken using replicate determinations, before and after injection of inflammatory substances or experimental nerve damage producing pain hypersensitivity, totaling 97,332 measurements. All mice were tested in the same physical laboratory over a 20-year period using similar equipment and procedures. We nonetheless find evidence of large interindividual variability, affected by tester, genotype, mouse sex, tester sex, replicate order, and injury. These factors are discussed, and we believe that these normative data will serve as a useful reference for expected values in preclinical pain testing. PERSPECTIVE: This article presents a retrospective analysis of a large data set of mouse von Frey and radiant heat paw-withdrawal (Hargreaves' test) measurements collected in a single laboratory over 20 years. In addition to serving as a normative guide, sources of variability are identified including genotype, tester, and sex.


Assuntos
Medição da Dor , Limiar da Dor , Animais , Camundongos , Feminino , Masculino , Medição da Dor/métodos , Estudos Retrospectivos , Limiar da Dor/fisiologia , Temperatura Alta/efeitos adversos , Dor/diagnóstico , Dor/fisiopatologia , Modelos Animais de Doenças , Estimulação Física , Hiperalgesia/diagnóstico , Hiperalgesia/fisiopatologia
2.
Ann R Coll Surg Engl ; 105(5): 434-440, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36239973

RESUMO

INTRODUCTION: Displaced distal radius fractures often require manipulation under anaesthesia. Many anaesthetic techniques are described, with the two most commonly used being Bier's block (BB) and haematoma block (HB). Despite national guidance preferring a BB, an HB is often performed instead. This study aims to compare the analgesic properties of a BB with those of an HB when manipulating distal radius fractures. METHODS: This is an observational cohort study comparing the management of displaced distal radius fractures requiring reduction across two National Health Service trusts. Patients aged over 18 with isolated, displaced distal radius fractures were recruited. Patient demographics, AO fracture classification and grade of clinician performing the procedure were recorded. A numeric rating scale (NRS) pain score was obtained for each patient after manipulation. The quality of reduction was judged against standardised anatomical parameters. RESULTS: Some 200 patients were recruited (100 HB, 100 BB). There were no differences in age (BB: median 66.5 years, interquartile range [IQR] 55-74; HB: median 67 years, IQR 55-74; p = 0.79) or fracture characteristics (p = 0.29) between cohorts. Patients undergoing BB had significantly lower pain scores with a lower IQR than those undergoing HB (p < 0.005). Patients undergoing BB manipulation were more likely to have the fracture reduced and normal anatomy restored (p < 0.005). BBs were performed mainly by Foundation Year 2 junior doctors, whereas HB manipulations were performed by a range of clinicians from emergency nurse practitioners to consultants. CONCLUSIONS: BB provides better analgesia than an HB. This can be performed successfully and reliably by Senior House Officer-level junior doctors.


Assuntos
Fraturas do Rádio , Fraturas do Punho , Humanos , Adolescente , Adulto , Idoso , Fraturas do Rádio/cirurgia , Medicina Estatal , Anestesia Local , Dor , Hematoma
3.
BMC Med Res Methodol ; 22(1): 229, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35971088

RESUMO

An increasing number of large-scale multi-modal research initiatives has been conducted in the typically developing population, e.g. Dev. Cogn. Neur. 32:43-54, 2018; PLoS Med. 12(3):e1001779, 2015; Elam and Van Essen, Enc. Comp. Neur., 2013, as well as in psychiatric cohorts, e.g. Trans. Psych. 10(1):100, 2020; Mol. Psych. 19:659-667, 2014; Mol. Aut. 8:24, 2017; Eur. Child and Adol. Psych. 24(3):265-281, 2015. Missing data is a common problem in such datasets due to the difficulty of assessing multiple measures on a large number of participants. The consequences of missing data accumulate when researchers aim to integrate relationships across multiple measures. Here we aim to evaluate different imputation strategies to fill in missing values in clinical data from a large (total N = 764) and deeply phenotyped (i.e. range of clinical and cognitive instruments administered) sample of N = 453 autistic individuals and N = 311 control individuals recruited as part of the EU-AIMS Longitudinal European Autism Project (LEAP) consortium. In particular, we consider a total of 160 clinical measures divided in 15 overlapping subsets of participants. We use two simple but common univariate strategies-mean and median imputation-as well as a Round Robin regression approach involving four independent multivariate regression models including Bayesian Ridge regression, as well as several non-linear models: Decision Trees (Extra Trees., and Nearest Neighbours regression. We evaluate the models using the traditional mean square error towards removed available data, and also consider the Kullback-Leibler divergence between the observed and the imputed distributions. We show that all of the multivariate approaches tested provide a substantial improvement compared to typical univariate approaches. Further, our analyses reveal that across all 15 data-subsets tested, an Extra Trees regression approach provided the best global results. This not only allows the selection of a unique model to impute missing data for the LEAP project and delivers a fixed set of imputed clinical data to be used by researchers working with the LEAP dataset in the future, but provides more general guidelines for data imputation in large scale epidemiological studies.


Assuntos
Transtorno Autístico , Transtorno Autístico/genética , Teorema de Bayes , Criança , Coleta de Dados/métodos , Humanos
4.
Radiography (Lond) ; 26(4): e246-e250, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32335020

RESUMO

INTRODUCTION: In the surveillance of children with cerebral palsy, the measurement of migration percentage is used to identify children at risk of hip dislocation. Early identification of children at risk facilitates early intervention with less invasive surgical procedures to prevent further deterioration. The aim of this study is to evaluate the safety of the measurements of migration percentage for surveillance in cerebral palsy by extended-role radiographers by evaluating the reliability and validity of measurements performed by these professionals. METHODS: A sample of thirty pelvic x-rays were selected from the local cerebral palsy database. A range of hip displacement was selected including some challenging borderline x-rays. All ten extended-role radiographers completed measurements using TraumaCAD which were repeated at a minimum of 4 weeks. Inter-rater and intra-rater reliability was calculated using intraclass correlation coefficients. The accuracy and safety of the system was evaluated by converting measurements into referral categories (red, amber or green) and cohen's kappa was calculated when categories were compared to measurements to orthopaedic surgeon RESULTS: The inter-rater reliability between radiographers was 0.938 (95% CI 0.914-0.991). The intra-rater reliability was 0.941 (95% CI 0.931-0.949). The percentage agreement was 94.8% for green, 93.8% for amber and 98.2% for red hips. The weighted kappa value was 0.923 (95% CI 0.889-0.957). CONCLUSION: The reliability and accuracy of radiographer measurement of migration percentage is excellent. It is safe for radiographers to calculate the migration percentage using semi-automated software for the surveillance of children with cerebral palsy. IMPLICATIONS FOR PRACTICE: We recommend the measurement of migration percentage may be performed by extended-role radiographers to deliver accurate and reliable measurements for use in cerebral palsy surveillance.


Assuntos
Paralisia Cerebral , Luxação do Quadril , Paralisia Cerebral/diagnóstico por imagem , Criança , Quadril , Luxação do Quadril/diagnóstico por imagem , Humanos , Radiografia , Reprodutibilidade dos Testes
5.
Poult Sci ; 98(11): 5809-5819, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31347673

RESUMO

The effect of essential total sulfur amino acids (TSAA) like methionine and cysteine on the cecal microbiome of broilers was investigated at 2 different time points (days 21 and 42) of broiler rearing. A total of 360-day-old Cobb male broiler chicks were randomly distributed to 6 dietary treatments in a 2 × 3 factorial arrangement, with 2 levels of antibiotic growth promoters (AGP: 0 and 0.05%) and 3 levels of TSAA (DL-methionine) either for starter (0.7, 0.8, and 0.9%) or finisher chicks (0.52, 0.62, and 0.72%), labeled as diets 1 to 6. Cecal digesta from each replicate (n = 10) were sampled on days 21 and 42. DNA was extracted for the amplification of the V4 region of bacterial 16S rRNA genes and subjected to Illumina sequencing. Bioinformatic analyses were performed using QIIME, Mothur, and ad hoc tools and functional profiles of the inferred metagenome were analyzed using PICRUST. Statistical difference was determined by 2-way ANOVA and PERMANOVA. Clustering of cecal communities using PCoA showed clear separation of microbial communities based on age (P < 0.05) of birds and between low and medium/ high levels of TSAA (DL-methionine). At day 21, bacterial richness and diversity were higher than at day 42 where Clostridium cluster XI and Lactobacillus were found most abundant. No variability in taxonomic richness at the genus level was observed with AGP and DL-methionine supplementation. Interbird variation for richness was greater at day 42 compared to day 21. The mean fold difference of richness was greater (1.5 mean fold) with diets 1 and 6, suggesting interactive effects of AGP and TSAA (DL-methionine) in the diet. KEGG function profiles calculated by PICRUST suggest that the cecal microbiome increased glycolysis and energy generation correlated with increased dietary TSAA (DL-methionine) supplementation levels during the late broiler growth period (day 42). This study increases our knowledge of microbial dynamics and functions that are relevant to host nutrition and performance that may help us tailoring alternative strategies for raising poultry birds under antibiotic-free conditions.


Assuntos
Aminoácidos Sulfúricos/metabolismo , Antibacterianos/farmacologia , Bacitracina/farmacologia , Ceco/microbiologia , Galinhas/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Racemetionina/metabolismo , Salicilatos/farmacologia , Aminoácidos Sulfúricos/administração & dosagem , Ração Animal/análise , Animais , Antibacterianos/administração & dosagem , Bacitracina/administração & dosagem , Galinhas/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Masculino , Racemetionina/administração & dosagem , Distribuição Aleatória , Salicilatos/administração & dosagem
6.
Stud Mycol ; 91: 1-22, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30104814

RESUMO

We have identified the cyclin domain-containing proteins encoded by the genomes of 17 species of Aspergillus as well as 15 members of other genera of filamentous ascomycetes. Phylogenetic analyses reveal that the cyclins fall into three groups, as in other eukaryotic phyla, and, more significantly, that they are remarkably conserved in these fungi. All 32 species examined, for example, have three group I cyclins, cyclins that are particularly important because they regulate the cell cycle, and these are highly conserved. Within the group I cyclins there are three distinct clades, and each fungus has a single member of each clade. These findings are in marked contrast to the yeasts Saccharomyces cerevisiae, Schizosaccharomyces pombe, and Candida albicans, which have more numerous group I cyclins. These results indicate that findings on cyclin function made with a model Aspergillus species, such as A. nidulans, are likely to apply to other Aspergilli and be informative for a broad range of filamentous ascomycetes. In this regard, we note that the functions of only one Aspergillus group I cyclin have been analysed (NimECyclin B of A. nidulans). We have consequently carried out an analysis of the members of the other two clades using A. nidulans as our model. We have found that one of these cyclins, PucA, is essential, but deletion of PucA in a strain carrying a deletion of CdhA, an activator of the anaphase promoting complex/cyclosome (APC/C), is not lethal. These data, coupled with data from heterokaryon rescue experiments, indicate that PucA is an essential G1/S cyclin that is required for the inactivation of the APC/C-CdhA, which, in turn, allows the initiation of the S phase of the cell cycle. Our data also reveal that PucA has additional, non-essential, roles in the cell cycle in interphase. The A. nidulans member of the third clade (AN2137) has not previously been named or analyzed. We designate this gene clbA. ClbA localizes to kinetochores from mid G2 until just prior to chromosomal condensation. Deletion of clbA does not affect viability. However, by using a regulatable promoter system new to Aspergillus, we have found that expression of a version of ClbA in which the destruction box sequences have been removed is lethal and causes a mitotic arrest and a high frequency of non-disjunction. Thus, although ClbA is not essential, its timely destruction is essential for viability, chromosomal disjunction, and successful completion of mitosis.

7.
Pain ; 159(7): 1224-1234, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29533388

RESUMO

It is well established that FKBP51 regulates the stress system by modulating the sensitivity of the glucocorticoid receptor to stress hormones. Recently, we have demonstrated that FKBP51 also drives long-term inflammatory pain states in male mice by modulating glucocorticoid signalling at spinal cord level. Here, we explored the potential of FKBP51 as a new pharmacological target for the treatment of persistent pain across the sexes. First, we demonstrated that FKBP51 regulates long-term pain states of different aetiologies independently of sex. Deletion of FKBP51 reduced the mechanical hypersensitivity seen in joint inflammatory and neuropathic pain states in female and male mice. Furthermore, FKBP51 deletion also reduced the hypersensitivity seen in a translational model of chemotherapy-induced pain. Interestingly, these 3 pain states were associated with changes in glucocorticoid signalling, as indicated by the increased expression, at spinal cord level, of the glucocorticoid receptor isoform associated with glucocorticoid resistance, GRß, and increased levels of plasma corticosterone. These pain states were also accompanied by an upregulation of interleukin-6 in the spinal cord. Crucially, we were able to pharmacologically reduce the severity of the mechanical hypersensitivity seen in these 3 models of persistent pain with the unique FKBP51 ligand SAFit2. When SAFit2 was combined with a state-of-the-art vesicular phospholipid gel formulation for slow release, a single injection of SAFit2 offered pain relief for at least 7 days. We therefore propose the pharmacological blockade of FKBP51 as a new approach for the treatment of persistent pain across sexes, likely in humans as well as rodents.


Assuntos
Inflamação/metabolismo , Neuralgia/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Animais , Feminino , Glucocorticoides/metabolismo , Inflamação/genética , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neuralgia/genética , Receptores de Glucocorticoides/metabolismo , Medula Espinal/metabolismo , Proteínas de Ligação a Tacrolimo/genética
8.
Ann R Coll Surg Engl ; 99(7): 550-554, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28682130

RESUMO

Introduction Emergency general surgery services in England are undergoing rapid structural change with the aim of improving care. In our centre, the key issues identified were high numbers of admissions, inappropriate referrals, prolonged waiting times, delayed senior input and poor patient satisfaction. A new model was launched in January 2015 to address these issues: the surgical triage unit (STU). This study assesses the success of the new service. Methods All emergency general surgical admissions during a five-month period before introduction of the STU were compared with those of a comparable five-month period after its introduction. Process, clinical and patient experience outcomes were assessed to identify improvement. Results Attendance fell from 3,304 patients in the 2014 cohort to 2,830 in the 2015 cohort. During the 2015 study period, 279 more patients were discharged on the same day. Resource requirement fell by 2,635 bed days (23%). The number of true surgical emergencies remained consistent. Rates for reattendance (7.8% for 2014 vs 8.1% for 2015) and readmission (5.7% for 2014 vs 5.7% for 2015) showed no significant difference. Patient experience data demonstrated a significant improvement in both net promoter score (64.1 vs 82.2) and number of complaints (34 vs 5). Clinical outcomes for low risk procedures remained similar. Emergency laparotomy in-hospital mortality fell (11.4% vs 10.3%) despite preoperative risk stratification suggesting a risk burden that was significantly higher than the national average. Conclusions This novel model of emergency general surgery provision has improved clinical efficiency, patient satisfaction and outcomes. We encourage other units to consider similar programmes of service improvement.


Assuntos
Consultores , Serviço Hospitalar de Emergência/organização & administração , Cirurgia Geral , Estudos Controlados Antes e Depois , Eficiência Organizacional , Serviço Hospitalar de Emergência/estatística & dados numéricos , Inglaterra , Cirurgia Geral/métodos , Cirurgia Geral/organização & administração , Humanos , Tempo de Internação/estatística & dados numéricos , Modelos Organizacionais , Alta do Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Melhoria de Qualidade
9.
BMJ Open ; 7(2): e014190, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28167748

RESUMO

OBJECTIVES: To determine if the introduction of the best practice tariff (BPT) has improved survival of the elderly hip fracture population, or if achieving BPT results in improved survival for an individual. SETTING: A single university-affiliated teaching hospital. PARTICIPANTS: 2541 patients aged over 60 admitted with a neck of femur fracture between 2008 and 2010 and from 2012 to 2014 were included, to create two cohorts of patients, before and after the introduction of BPT. The post-BPT cohort was divided into two groups, those who achieved the criteria and those who did not. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes of interest were differences in mortality across cohorts. Secondary analysis was performed to identify associations between individual BPT criteria and mortality. RESULTS: The introduction of BPT did not significantly alter overall 30-mortality in the hip fracture population (8.3% pre-BPT vs 10.0% post-BPT; p=0.128). Neither was there a significant reduction in length of stay (15 days (IQR 9-21) pre-BPT vs 14 days (IQR 11-22); p=0.236). However, the introduction of BPT was associated with a reduction in the time from admission to theatre (median 44 hours pre-BPT (IQR 24-44) vs 23 hours post-BPT (IQR 17-30); p<0.005). 30-day mortality in those who achieved BPT was significantly lower (6.0% vs 21.0% in those who did not achieve-BPT; p<0.005). There was a survival benefit at 1 year for those who achieved BPT (28.6% vs 42.0% did not achieve-BPT; p<0.005). Multivariate logistic regression revealed that of the BPT criteria, AMT monitoring and expedited surgery were the only BPT criteria that significantly influenced survival. CONCLUSIONS: The introduction of the BPT has not led to a demonstrable improvement in outcomes at organisational level, though other factors may have confounded any benefits. However, patients where BPT criteria are met appear to have improved outcomes.


Assuntos
Fidelidade a Diretrizes/estatística & dados numéricos , Fraturas do Quadril/mortalidade , Guias de Prática Clínica como Assunto , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Hospitais de Ensino , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Modelos Logísticos , Masculino , Análise Multivariada , Estudos Retrospectivos , Reino Unido
10.
J Neurochem ; 138(2): 222-32, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26998823

RESUMO

Histone deacetylases (HDACs), HDAC2 in particular, have been shown to regulate various forms of learning and memory. Since cognitive processes share mechanisms with spinal nociceptive signalling, we decided to investigate the HDAC2 expression in the dorsal horn after peripheral injury. Using immunohistochemistry, we found that spinal HDAC2 was mainly seen in neurons and astrocytes, with neuronal expression in naïve tissue 2.6 times greater than that in astrocytes. Cysteine (S)-nitrosylation of HDAC2 releases HDAC2 gene silencing and is controlled by nitric oxide (NO). A duration of 48 h after intraplantar injection of complete Freund's adjuvant, there was an ipsilateral increase in the most important NO-producing enzyme in pain states, nitric oxide synthase (nNOS), accompanied by an increase in HDAC2 S-nitrosylation. Moreover, a subset of nNOS-positive neurons expressed cFos, a known target of HDAC2, suggesting that derepression of cFos expression following HDAC2 S-nitrosylation might occur after noxious stimulation. We saw no change in global HDAC2 expression in both short- and long-term pain states. However, HDAC2 was increased in astrocytes 7 days after neuropathic injury suggesting that HDAC2 might inhibit astrocytic gene expression in neuropathic pain states. All together, our results indicate that the epigenetic regulation of transcriptional programmes in the dorsal horn after injury is cell specific. Moreover, the prominent role of NO in persistent pain states suggests that HDAC2 S-nitrosylation could play a crucial role in the regulation of gene expression leading to hypersensitivity. Our manuscript describes for the first time the regulation of the memory regulator histone deacetylase 2 (HDAC2) in the superficial dorsal horn of adult rats following peripheral injury. Our cell-specific approach has revealed a complex pattern of expression of spinal HDAC2 that depends on the injury and the cell type, suggesting a sophisticated regulation of gene expression by HDAC2.


Assuntos
Histona Desacetilase 2/metabolismo , Plasticidade Neuronal/fisiologia , Traumatismos dos Nervos Periféricos/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , Animais , Astrócitos/metabolismo , Epigênese Genética/genética , Histona Desacetilase 2/genética , Masculino , Neuralgia/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Células do Corno Posterior/metabolismo , Ratos Sprague-Dawley
11.
J Food Prot ; 79(11): 1986-1989, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-28221919

RESUMO

The objective of this study was to compare subtypes of Campylobacter jejuni and Campylobacter coli detected on three selective Campylobacter plating media to determine whether each medium selected for different subtypes. Fifty ceca and 50 carcasses (representing 50 flocks) were collected from the evisceration line in a commercial broiler processing plant. Campylobacter was cultured and isolated from cecal contents and carcass rinses on Campy-Cefex, Campy Line, and RF Campylobacter jejuni/coli agars. When a positive result was obtained with all three media, one colony of the most prevalent morphology on each medium was selected for further analysis by full genome sequencing and multilocus sequence typing. Sequence types were assigned according to PubMLST. A total of 49 samples were positive for Campylobacter on all three media. Forty samples contained only C. jejuni , three had only C. coli , and both species were detected in six samples. From 71% of samples, Campylobacter isolates of the same sequence type were recovered on all three media. From 81.6% of samples, isolates were all from the same clonal complex. From significantly fewer samples (26%, P < 0.01), one medium recovered an isolate with a sequence type different from the type recovered on the other two media. When multiple sequence types were detected, six times the medium with the odd sequence type was Campy-Cefex, four times it was Campy-Line, and six times it was RF Campylobacter jejuni/coli . From one sample, three sequence types were detected. In most cases, all three plating media allowed detection of the same type of Campylobacter from complex naturally contaminated chicken samples.


Assuntos
Campylobacter/genética , Galinhas , Animais , Campylobacter coli/genética , Campylobacter jejuni/genética , Tipagem de Sequências Multilocus
12.
Chem Sci ; 7(3): 2322-2330, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29910922

RESUMO

Research into the chemical biology of bromodomains has been driven by the development of acetyl-lysine mimetics. The ligands are typically anchored by binding to a highly conserved asparagine residue. Atypical bromodomains, for which the asparagine is mutated, have thus far proven elusive targets, including PHIP(2) whose parent protein, PHIP, has been linked to disease progression in diabetes and cancers. The PHIP(2) binding site contains a threonine in place of asparagine, and solution screening have yielded no convincing hits. We have overcome this hurdle by combining the sensitivity of X-ray crystallography, used as the primary fragment screen, with a strategy for rapid follow-up synthesis using a chemically-poised fragment library, which allows hits to be readily modified by parallel chemistry both peripherally and in the core. Our approach yielded the first reported hit compounds of PHIP(2) with measurable IC50 values by an AlphaScreen competition assay. The follow-up libraries of four poised fragment hits improved potency into the sub-mM range while showing good ligand efficiency and detailed structural data.

13.
Appl Environ Microbiol ; 79(16): 4806-14, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23747695

RESUMO

IncA/C plasmids are a class of plasmids from the Enterobacteriaceae that are relatively large (49 to >180 kbp), that are readily transferred by conjugation, and that carry multiple antimicrobial resistance genes. Reconstruction of the phylogeny of these plasmids has been difficult because of the high rate of remodeling by recombination-mediated horizontal gene transfer (HGT). We hypothesized that evaluation of nucleotide polymorphisms relative to the rate of HGT would help to develop a clock to show whether anthropic practices have had significant influences on the lineages of the plasmid. A system was developed to rapidly sequence up to 191 known open reading frames from each of 39 recently isolated IncA/C plasmids from a diverse panel of Salmonella enterica and Escherichia coli strains. With these data plus sequences from GenBank, we were able to distinguish six distinct lineages that had extremely low numbers of polymorphisms within each lineage, especially among the largest group designated as group 1. Two regions, each about half the plasmid in size, could be distinguished with a separate lineal pattern. The distribution of group 1 showed that it has migrated extremely rapidly with fewer polymorphisms than can be expected in 2,000 years. Remodeling by frequent HGT was evident, with a pattern that appeared to have the highest rate just upstream of the putative conjugation origin of transfer (oriT). It seems likely that when an IncA/C plasmid is transferred by conjugation there is an opportunity for plasmid remodeling adjacent to the oriT, which was also adjacent to a multiple antimicrobial resistance gene cassette.


Assuntos
Bactérias/genética , DNA Bacteriano/genética , Fases de Leitura Aberta , Plasmídeos/genética , Bactérias/metabolismo , DNA Bacteriano/metabolismo , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Plasmídeos/metabolismo , Análise de Sequência de DNA , Homologia de Sequência
14.
Poult Sci ; 92(1): 218-24, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23243251

RESUMO

The whole carcass rinse (WCR) procedure is routinely used as a sampling method for determining the presence and number of quality-indicator organisms or pathogens associated with broiler chicken carcasses in processing facilities. Collection of a cumulative drip sample by placing collection vessels under the processing line could potentially capture a more representative sample of bacterial populations associated with an entire flock with less labor than individual bird rinses. The purpose of this study was to evaluate a cumulative drip sampling method for recovery of Campylobacter spp. and 3 types of quality indicator organisms from broiler carcasses. Cumulative drip and WCR samples were collected on 14 d from a commercial broiler processing facility over a 3-mo period. No statistically significant difference was demonstrated between the WCR and cumulative drip sampling methods in recovery of Campylobacter spp., total aerobes, Enterobacteriaceae, or Escherichia coli associated with the postevisceration samples (P > 0.01). Analysis of the pyrosequencing census data demonstrated high interbird variability and indicates cumulative sampling may be required to obtain fully representative sampling of a flock. For most bacterial taxa, the relative abundance in individual WCR was correlated with cumulative drip samples, but some taxa were undercounted or missed entirely by individual WCR. Consequently, individual carcass rinses may not be representative of the flock microbial community. The cumulative drip sampling technique may save labor and provide a more representative summary of process control in poultry processing facilities.


Assuntos
Campylobacter/isolamento & purificação , Galinhas/microbiologia , Matadouros , Animais , Qualidade de Produtos para o Consumidor , Microbiologia de Alimentos , Microbiologia da Água
15.
J Food Prot ; 74(9): 1558-63, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21902928

RESUMO

An instrument (TEMPO) has been developed to automate the most-probable-number (MPN) technique and reduce the effort required to estimate some bacterial populations. We compared the automated MPN technique with traditional microbiological plating methods and Petrifilm methods for estimating the total viable count of aerobic microorganisms (TVC), total coliforms (CC), and Escherichia coli populations (EC) on freshly processed broiler chicken carcasses (postchill whole carcass rinse [WCR] samples) and cumulative drip-line samples from a commercial broiler processing facility. Overall, 120 broiler carcasses, 36 prechill drip-line samples, and 40 postchill drip-line samples were collected over 5 days (representing five individual flocks) and analyzed by the automated MPN and direct agar plating and Petrifilm methods. The TVC correlation coefficient between the automated MPN and traditional methods was very high (0.972) for the prechill drip samples, which had mean log-transformed values of 3.09 and 3.02, respectively. The TVC correlation coefficient was lower (0.710) for the postchill WCR samples, which had lower mean log values of 1.53 and 1.31, respectively. Correlations between the methods for the prechill CC and EC samples were 0.812 and 0.880, respectively. The estimated number of total aerobes was generally greater than the total number of coliforms or E. coli recovered for all sample types (P < 2e⁻¹6). Significantly more bacteria were recovered from the prechill samples than from the postchill WCR or cumulative drip samples (P < 9.5e⁻¹² and P < 2e⁻¹6, respectively). When samples below the limit of detection were excluded, 92.1% of the total responses were within a single log difference between the traditional plating or Petrifilm methods and the automated MPN method.


Assuntos
Bactérias Aeróbias/isolamento & purificação , Galinhas/microbiologia , Contagem de Colônia Microbiana/instrumentação , Contagem de Colônia Microbiana/métodos , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Ágar , Animais , Qualidade de Produtos para o Consumidor , Meios de Cultura , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Humanos , Fatores de Tempo
16.
mBio ; 1(3)2010 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-20802828

RESUMO

Nonhost environmental reservoirs of pathogens play key roles in their evolutionary ecology and in particular in the evolution of pathogenicity. In light of recent reports of the plant pathogen Pseudomonas syringae in pristine waters outside agricultural regions and its dissemination via the water cycle, we have examined the genetic and phenotypic diversity, population structure, and biogeography of P. syringae from headwaters of rivers on three continents and their phylogenetic relationship to strains from crops. A collection of 236 strains from 11 sites in the United States, in France, and in New Zealand was characterized for genetic diversity based on housekeeping gene sequences and for phenotypic diversity based on measures of pathogenicity and ice nucleation activity. Phylogenetic analyses revealed several new genetic clades from water. The genetic structure of P. syringae populations was not influenced by geographic location or water chemistry, whereas the phenotypic structure was affected by these parameters. Comparison with strains from crops revealed that the metapopulation of P. syringae is structured into three genetic ecotypes: a crop-specific type, a water-specific type, and an abundant ecotype found in both habitats. Aggressiveness of strains was significantly and positively correlated with ice nucleation activity. Furthermore, the ubiquitous genotypes were the most aggressive, on average. The abundance and diversity in water relative to crops suggest that adaptation to the freshwater habitat has played a nonnegligible role in the evolutionary history of P. syringae. We discuss how adaptation to the water cycle is linked to the epidemiological success of this plant pathogen.


Assuntos
Evolução Biológica , Doenças das Plantas/microbiologia , Pseudomonas syringae/genética , Pseudomonas syringae/isolamento & purificação , Rios/microbiologia , Europa (Continente) , Variação Genética , Dados de Sequência Molecular , Nova Zelândia , América do Norte , Filogenia , Pseudomonas syringae/classificação , Rios/química
17.
Transplant Proc ; 35(4): 1435-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12826182

RESUMO

BACKGROUND: Due to the early age that pediatric patients with autoimmune hepatitis (AIH) are transplanted, it is theorized that older AIH patients may have different outcomes than pediatric patients following liver transplantation. METHODS: This is a retrospective review of both the adult and pediatric liver transplant programs consisting of 56 patients. Rejection and recurrence of AIH were determined by biopsy. RESULTS: The autoimmune patient having rejection episodes had a 1.76-fold increase in relative risk to develop autoimmune recurrence when compared to patients without rejection [RR = 1.76; 95% CIRR (1.08, 2.86)]. The pediatric group had a 6.62-fold increase in relative risk to develop colitis following liver transplantation [RR = 6.62; 95% C.I.R.R. (1.36, 32.13); P =.02]. Mean days to recurrence of AIH were similar in both groups (1364 +/- 1074 vs 936; P = NS). There were more hospitalized days in the pediatric group compared to the adults (20.5 +/- 13.3 days vs 51.7 +/- 22.2 days, P =.039). OKT-3 was rarely used (n = 5) in either group (9.3% vs 7.7%, P = NS) and was not correlated with which patients would be weaned from steroids or recurrence. CONCLUSIONS: Based on this review, pediatric patients were more likely to develop ulcerative colitis following liver transplantation and they incurred longer hospital stays than adults. The adult group was more likely to be weaned from steroids, with AIH recurrence unrelated to weaning.


Assuntos
Hepatite Autoimune/cirurgia , Transplante de Fígado , Adulto , Criança , Colite/epidemiologia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/epidemiologia , Recidiva , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
19.
Mol Biol Cell ; 12(10): 3161-74, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11598200

RESUMO

Previous research has found that a gamma-tubulin mutation in Schizosaccharomyces pombe is synthetically lethal with a deletion of the C-terminal motor domain kinesin-like protein gene pkl1, but the lethality of the double mutant prevents a phenotypic analysis of the synthetic interaction. We have investigated interactions between klpA1, a deletion of an Aspergillus nidulans homolog of pkl1, and mutations in the mipA, gamma-tubulin gene. We find that klpA1 dramatically increases the cold sensitivity and slightly reduces the growth rate at all temperatures, of three mipA alleles. In synchronized cells we find that klpA1 causes a substantial but transient inhibition of the establishment of spindle bipolarity. At a restrictive temperature, mipAD123 causes a slight, transient inhibition of spindle bipolarity and a more significant inhibition of anaphase A. In the mipAD123/klpA1 strain, formation of bipolar spindles is more strongly inhibited than in the klpA1 single mutant and many spindles apparently never become bipolar. These results indicate, surprisingly, that gamma-tubulin and the klpA kinesin have overlapping roles in the establishment of spindle bipolarity. We propose a model to account for these data.


Assuntos
Aspergillus nidulans/citologia , Aspergillus nidulans/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Cinesinas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Mitose/fisiologia , Proteínas de Schizosaccharomyces pombe , Fuso Acromático/fisiologia , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Alelos , Anáfase/fisiologia , Núcleo Celular , Temperatura Baixa , Deleção de Genes , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação/genética , Mutação/fisiologia , Estrutura Terciária de Proteína/fisiologia
20.
Med Hypotheses ; 57(4): 515-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11601882

RESUMO

Noninvasive cardiac pressure sensing using an imaging modality to ascertain changes in absolute pressure would be of immense benefit as a replacement for the Swan-Ganz catheter in current use. However, very little research has been published in this area. This paper reviews the small number of relevant studies to date, points out the many gaps in the research record, and discusses possible new avenues of approach in solving the problem.


Assuntos
Testes de Função Cardíaca/métodos , Coração/fisiologia , Humanos
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