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1.
Cochrane Database Syst Rev ; 4: CD012746, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37115724

RESUMO

BACKGROUND: Conduct problems are a range of disruptive behaviours in childhood that are associated with long-term adverse outcomes in adolescence and adulthood, including antisocial behaviour, substance misuse, and poor academic achievement. Children with conduct problems can vary according to age of onset, comorbidities, and environmental factors, and it has been suggested that certain groups of children may have different treatment outcomes. Therefore, it is important to assess the extent to which personalised interventions for different groups of children with conduct problems may affect outcomes. To our knowledge, this is the first review to systematically identify and appraise the effectiveness of personalised interventions, adapted, or developed, for prespecified subgroups of children with conduct problems. OBJECTIVES: To assess whether personalised interventions, adapted or developed for subgroups of children with conduct problems are effective in improving outcomes. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search was 1 February 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs), in any setting, in children (aged two to 12 years) with conduct problems and within a prespecified subgroup, comparing a personalised intervention with a non-personalised intervention, waitlist control, or treatment as usual. Personalised interventions included adaptations to standard practice, such as parent-training programmes; other recommended interventions for children with conduct problems; or interventions developed specifically to target subgroups of children with conduct problems. We excluded non-personalised and non-psychological interventions (e.g. pharmacological or dietary intervention). Prespecified subgroups of children with conduct problems, however defined, were eligible for inclusion. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. child conduct problems or disruptive behaviour and 2. ADVERSE EVENTS: Our secondary outcomes were 3. personalised treatment outcomes relevant to each subgroup, 4. parenting skills and knowledge, 5. family functioning, engagement and decreased dropout, and 6. educational outcomes. We used GRADE to assess the certainty of the evidence. MAIN RESULTS: We identified 13 RCTs (858 participants). Seven studies were conducted in the USA, five in Australia, and one in Germany. Eleven studies reported their source of funding, with five studies receiving grants from the National Institute of Mental Health. In total, 15 different funders supported the studies included in the review. We separated subgroups of children with conduct problems into three broad categories: children with co-occurring conditions (e.g. emotional difficulties), parent characteristics (e.g. conflict between parents), or familial/environmental circumstances (e.g. rural families). All studies delivered a personalised intervention that was adapted or developed for a prespecified subgroup of children with conduct problems. We rated all trials at unclear or high risk of bias in most domains. Below, we report the results of improvement in child conduct problems and disruptive behaviour, personalised treatment outcomes, and parenting skills and knowledge for our main comparison: personalised versus non-personalised interventions. Improvement in child conduct problems and disruptive behaviour Compared with a non-personalised intervention, a personalised intervention may result in a slight improvement in child conduct problems or disruptive behaviour measured using the Eyberg Child Behavior Inventory (ECBI) Problem subscale in the short term (mean difference (MD) -3.04, 95% confidence interval (CI) -6.06 to -0.02; 6 studies, 278 participants; P = 0.05), but may have little to no effect on improving child conduct problems or disruptive behaviour measured by the ECBI Intensity subscale (MD -6.25, 95% CI -16.66 to 4.15; 6 studies, 278 participants; P = 0.24), or the Externalising subscale of the Child Behaviour Checklist (CBCL) (MD -2.19, 95% CI -6.97 to 2.59; 3 studies, 189 participants, P = 0.37) in the short term. We graded the certainty of evidence as very low for all three outcomes, meaning any estimate of effect is very uncertain.  Personalised treatment outcomes, relevant to each subgroup Although six studies reported personalised treatment outcomes, relevant to each subgroup, we were unable to pool the data due to differences between the measures used in the studies and the heterogeneity this would produce in analysis. The results for this outcome were inconclusive. Parenting skills and knowledge Although seven studies reported parenting skills and knowledge, we were unable to pool the data due to differences between the measures used in the studies and the heterogeneity this would produce in analysis. The results for this outcome were inconclusive.  Adverse events None of the trials reported monitoring adverse events. Summary of results In summary, there is limited evidence that personalised intervention improves child conduct problems, personalised treatment outcomes, relevant to each subgroup, or parenting skills and knowledge compared with a non-personalised intervention. AUTHORS' CONCLUSIONS: There is limited evidence for the effectiveness of personalised interventions for subgroups of children with conduct problems. The certainty of evidence for all outcomes was very low, meaning that we have very little confidence in the estimated effects and the true effects may be different to our findings, which will limit the relevance of our findings to clinical decisions. To overcome the limitations of the evidence, large-scale RCTs are needed to determine whether personalised interventions, adapted or developed, for subgroups of children with conduct problems are effective in improving outcomes. Consensus on the most appropriate measures to use in these studies is needed in order to facilitate cross-study comparisons. Persistent conduct problems predict a range of adverse long-term outcomes, so future research should investigate the medium- and long-term effects of personalised treatments. Studies are needed in low- and middle-income countries as well as studies recruiting children aged between nine and 12 years, as they were under-represented in the studies.


Assuntos
Comportamento Problema , Adolescente , Criança , Humanos , Comportamento Infantil , Educação Infantil , Emoções , Pais/psicologia , Estados Unidos
2.
Anal Bioanal Chem ; 414(8): 2767-2774, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35106614

RESUMO

Analysis of the dipicolinic acid (DPA) released from Clostridium botulinum spores during thermal processing is crucial to obtaining a mechanistic understanding of the factors involved in spore heat resistance and related food safety applications. Here, we developed a novel mixed-mode liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection of the DPA released from C. botulinum type A, nonproteolytic types B and F strains, and nonpathogenic surrogate Clostridium sporogenes PA3679 spores. DPA was retained on a mixed-mode C18/anion exchange column and was detected using electrospray ionization (ESI) positive mode within a 4-min analysis time. The intraday and interday precision (%CV) was 1.94-3.46% and 4.04-8.28%, respectively. Matrix effects were minimal across proteolytic type A Giorgio-A, nonproteolytic types QC-B and 202-F, and C. sporogenes PA3679 spore suspensions (90.1-114% of spiked DPA concentrations). DPA recovery in carrot juice and beef broth ranged from 105 to 118%, indicating limited matrix effects of these food products. Experiments that assessed the DPA released from Giorgio-A spores over the course of a 5-min thermal treatment at 108 °C found a significant correlation (R = 0.907; P < 0.05) between the log reduction of spores and amount of DPA released. This mixed-mode LC-MS/MS method provides a means for rapid detection of DPA released from C. botulinum spores during thermal processing and has the potential to be used for experiments in the field of food safety that assess the thermal resistance characteristics of various C. botulinum spore types.


Assuntos
Clostridium botulinum , Ácidos Picolínicos , Cromatografia Líquida , Clostridium botulinum/química , Temperatura Alta , Ácidos Picolínicos/análise , Esporos Bacterianos/química , Espectrometria de Massas em Tandem
3.
Attach Hum Dev ; 23(4): 355-374, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33978553

RESUMO

Attachment concepts are used in diverging ways, which has caused confusion in communication among researchers, among practitioners, and between researchers and practitioners, and hinders their potential for collaboration. In this essay we explore how attachment concepts may vary in meaning across six different domains: popular discourses, developmental science, social psychological science, psychiatric diagnosis, psychotherapy, and child welfare practice. We attempt to typify these forms of attachment discourse by highlighting points of convergence, divergence, and relay between the different domains. Our general conclusions are that diversity in the use of attachment concepts across different domains of application has been largely unrecognised, and that recognition of these differences would reduce confusion, help identify sites where infrastructure needs to be developed to support coordination, and strengthen opportunities for collaboration to mutual benefit. We suggest that academic attachment discourse would benefit from clarification of core terminology, including: "attachment", "internal working model", "trauma", and "dysregulation".


Assuntos
Transtornos Mentais , Apego ao Objeto , Criança , Humanos , Psicoterapia
4.
Crim Behav Ment Health ; 31(3): 211-219, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33951229

RESUMO

BACKGROUND: Previous research has suggested that people with a history of offending have worse health compared to non-offenders, but it is less clear whether all types of offenders are at similar health risks. In a New Zealand birth cohort study, Moffitt evidenced three main offending trajectories-life-course-persistent (LCP), adolescence-limited (AL) and late-onset (LO) offending, subsequently confirmed in other substantial longitudinal studies. AIMS: Our aim was to explore the relationship between these offending trajectories and both self-reported (SR) and general practitioner (GP) (primary care) recorded health indicators. METHODS: Self-reported medical data at age 48 were obtained for 394 men followed since age 8 years in the Cambridge Study in Delinquent Development. In addition, medical records were obtained from GPs for 264 of them. Health indicators from both sources were compared between each of the three established trajectories of offenders across the life course-LCP, AL, LO and the non-offenders. RESULTS: LCP offenders were found to have over twice the likelihood of disabling medical conditions according to both self-report and GP records. They were also more likely to have GP records indicating mental health problems and treatment for them. According to GP records alone, the LO offenders were also more likely to have mental health problems. The health of AL offenders appeared to be no different from that of the crime-free controls. CONCLUSIONS: Our findings add weight to the growing evidence that LCP offending and offending that only occurs relatively late in life are likely to be the indicators of generally unhealthy and disrupted lives. This suggests that if lifestyle is to change for the better, interventions are likely to be needed for health as well as antisocial behaviour.


Assuntos
Criminosos , Clínicos Gerais , Adolescente , Criança , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Autorrelato
7.
Appl Environ Microbiol ; 82(1): 384-93, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26519392

RESUMO

Clostridium sporogenes PA 3679 is a nonpathogenic, nontoxic model organism for proteolytic Clostridium botulinum used in the validation of conventional thermal food processes due to its ability to produce highly heat-resistant endospores. Because of its public safety importance, the uncertain taxonomic classification and genetic diversity of PA 3679 are concerns. Therefore, isolates of C. sporogenes PA 3679 were obtained from various sources and characterized using pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. The phylogenetic relatedness and genetic variability were assessed based on 16S rRNA gene sequencing and whole-genome single nucleotide polymorphism (SNP) analysis. All C. sporogenes PA 3679 isolates were categorized into two clades (clade I containing ATCC 7955 NCA3679 isolates 1961-2, 1990, and 2007 and clade II containing PA 3679 isolates NFL, UW, FDA, and Campbell and ATCC 7955 NCA3679 isolate 1961-4). The 16S maximum likelihood (ML) tree clustered both clades within proteolytic C. botulinum strains, with clade I forming a distinct cluster with other C. sporogenes non-PA 3679 strains. SNP analysis revealed that clade I isolates were more similar to the genomic reference PA 3679 (NCTC8594) genome (GenBank accession number AGAH00000000.1) than clade II isolates were. The genomic reference C. sporogenes PA 3679 (NCTC8594) genome and clade I C. sporogenes isolates were genetically distinct from those obtained from other sources (University of Wisconsin, National Food Laboratory, U.S. Food and Drug Administration, and Campbell's Soup Company). Thermal destruction studies revealed that clade I isolates were more sensitive to high temperature than clade II isolates were. Considering the widespread use of C. sporogenes PA 3679 and its genetic information in numerous studies, the accurate identification and genetic characterization of C. sporogenes PA 3679 are of critical importance.


Assuntos
Clostridium/classificação , Clostridium/genética , DNA Bacteriano/genética , Variação Genética , Clostridium/isolamento & purificação , Clostridium botulinum/genética , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular , Filogenia , Polimorfismo de Nucleotídeo Único , RNA Ribossômico 16S , Esporos Bacterianos , Estados Unidos
8.
Food Microbiol ; 44: 149-55, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25084657

RESUMO

Clostridium botulinum is an important foodborne pathogen capable of forming heat resistant endospores and producing deadly botulinum neurotoxins (BoNTs). In 2006, C. botulinum was responsible for an international outbreak of botulism attributed to the consumption of commercially pasteurized carrot juice. The purpose of this study was to isolate and characterize strains of C. botulinum from the adulterated product. Carrot juice bottles retrieved from the manufacturing facility were analyzed for the presence of BoNT and BoNT-producing isolates using DIG-ELISA. Toxigenic isolates from the carrot juice were analyzed using pulsed-field gel electrophoresis (PFGE) and DNA microarray analysis to determine their genetic relatedness to the original outbreak strains CDC51348 and CDC51303. PFGE revealed that isolates CJ4-1 and CJ10-1 shared an identical pulsotype with strain CDC51303, whereas isolate CJ5-1 displayed a unique restriction banding pattern. DNA microarray analysis identified several phage related genes unique to strain CJ5-1, and Southern hybridization analysis of XhoI digested and nondigested DNA showed their chromosomal location, while a homolog to pCLI_A009 of plasmid pCLI of C. botulinum serotype Langeland F, was located on a small plasmid. The acquisition or loss of bacteriophages and other mobile genetic elements among C. botulinum strains has epidemiological and evolutionary implications.


Assuntos
Bebidas/microbiologia , Clostridium botulinum/isolamento & purificação , Daucus carota/microbiologia , Bebidas/análise , Bebidas/economia , Clostridium botulinum/classificação , Clostridium botulinum/genética , Daucus carota/química , Daucus carota/economia , Contaminação de Alimentos/análise , Contaminação de Alimentos/economia , Dados de Sequência Molecular , Pasteurização , Filogenia , Plasmídeos/genética
9.
Campbell Syst Rev ; 20(2): e1403, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38756221

RESUMO

This is the protocol for a Campbell systematic review. The objectives are as follows. The primary aim of this mixed methods review is to synthesise the available evidence regarding the effectiveness of restorative justice interventions (RJIs) for reducing offending and reoffending outcomes in children and young people. We are also particularly interested in the impact of RJIs on children and young peoples' violent offending and violent reoffending. A second aim of the review is to examine whether the magnitude of effectiveness of RJIs may be influenced by study characteristics such as the population (e.g., age, ethnicity, or sex), the form of intervention (e.g., face-to-face mediation compared to family group conferencing), the place of delivery of the intervention (e.g., in independent office, in court), implementation (e.g., trained facilitators, dose, fidelity) and methodology (e.g., randomised controlled trial). The third aim of the review is to synthesise the qualitative evidence about RJ to develop a better contextual understanding of how these programmes may work and to elucidate factors that might increase the efficacy and implementation of RJ interventions. The specific research questions this systematic review aims to address are: (1) Do RJ interventions reduce children and young people's involvement in offending or reoffending relative to a comparison group? [RQ1]. (2) Is there variation in the impact of different RJ approaches on young people's involvement in offending or reoffending? [RQ2]. (3) Is there variation in the impact of RJIs on children and young people's offending or reoffending depending on the characteristics of the participants taking part in the RJI (e.g., sex, age, ethnicity)? [RQ3]. (4) What characteristics of RJIs, influence the effectiveness of RJIs for children and young people's offending and reoffending? [RQ4]. (5) What are the most notable barriers and facilitators, as reported by participants (e.g., the victims, children/young people, or mediators who have taken part in an evaluation of an RJI, or those children or young people who were meant to take part in an evaluation but ultimately did not), to the implementation of RJIs to reduce later offending or reoffending? [RQ5].

10.
J Food Prot ; 87(10): 100359, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39260571

RESUMO

Dipicolinic acid (DPA) is a major constituent of spores and reportedly provides protection against inactivation by various thermal processes; however, the relationship between DPA and resistance towards pressure-assisted thermal processing is not well understood. Thermal and pressure-assisted thermal inactivation studies of Clostridium botulinum nonproteolytic strains QC-B and 610-F, proteolytic strain Giorgio-A, and thermal surrogate Clostridium sporogenes PA3679 spores suspended in ACES buffer (0.05 M, pH 7.0) were performed to determine if a relationship exists between DPA release and log reduction of spores. Thermal inactivation at 80, 83, and 87 °C for nonproteolytic strains and 101, 105, and 108 °C for the proteolytic strain and thermal surrogate were conducted. Pressure-assisted thermal inactivation for nonproteolytic strains at 83 °C/600 MPa and for the proteolytic strain and thermal surrogate at 105 °C/600 MPa were performed. Surviving spores were enumerated by 5-tube MPN method for log reductions and analyzed for released DPA by liquid chromatography-tandem mass spectrometry. The correlation between MPN log reductions, released DPA, and D-values were calculated. A positive correlation between released DPA and log reduction of spores was observed for QC-B and 610-F at 80 and 83 °C (r = 0.6073 - 0.7755; P < 0.01). At 87 °C, a positive correlation was detected for 610-F (r = 0.4242, P < 0.05) and no correlation was observed for QC-B (r = 0.1641; P > 0.05). A strong, positive correlation (r = 0.8359 - 0.9284; P < 0.05) between released DPA and log reduction of spores was observed for Giorgio-A at 101, 105, and 108 °C, and a strong, positive correlation (r = 0.8402; P < 0.05) was observed for PA3679 at 101 °C. A positive correlation (r = 0.5646 - 0.6724; P < 0.01) was observed for QC-B, 610-F, and Giorgio-A after pressure-assisted thermal treatment. No correlation (r = 02494; P > 0.05) was found for PA3679 after pressure-assisted thermal treatment. These results suggest a correlation exists between DPA release and heat resistance; however, the level of correlation varied between strains and temperatures. The findings from this research may aid in the development of spore inactivation strategies targeting the thermal resistance profiles of various strains of C. botulinum spores.

11.
Int J Offender Ther Comp Criminol ; 67(8): 757-782, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34963375

RESUMO

Research suggests that convicted persons are more likely than non-convicted persons to suffer poor health. However, few longitudinal studies have investigated associations between health and offending across generations. Using the Cambridge Study in Delinquent Development, this article prospectively investigates the relationship between health and offending across generations and between genders. At the average age of 25, third generation convicted males and females reported a higher incidence of serious drug use than non-convicted persons. Convicted males reported a higher incidence of mental illness and self-harm, whereas convicted females reported a lower incidence of physical illness, mental illness, self-harm and hospitalizations when compared to non-convicted females. Convicted males reported a higher incidence of industrial accidents, sports injuries and fight injuries, but a lower incidence of road accidents, whereas convicted females were more likely to report road accidents. Like their fathers, convicted males show worse health compared to non-convicted individuals.


Assuntos
Transtorno da Personalidade Antissocial , Hospitalização , Humanos , Masculino , Feminino , Adulto , Fatores de Risco , Estudos Longitudinais , Incidência , Transtorno da Personalidade Antissocial/epidemiologia
12.
Campbell Syst Rev ; 18(4): e1286, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36908837

RESUMO

This is the protocol for a Campbell systematic review. The review will address the following research questions: What is the evidence on the effects of adult mentoring programmes in reducing anti-social, violent and offending behaviour in children aged under 18 years? Are these effects sustained after the end of mentoring? Which aspects/features of adult mentoring programmes promote the reduction of anti-social, violent and criminal behaviour in children aged under 18 years? What are the hindering factors/barriers that affect the successful implementation of adult mentoring programmes in children aged under 18 years? What are the supporting factors/facilitators that contribute to the successful implementation of adult mentoring programmes in children aged under 18 years? What is the evidence on programme costs and incremental cost effectiveness? (The incremental (or marginal cost) is the cost of providing the intervention over and above the cost of usual services).

13.
J Food Prot ; 84(3): 442-448, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33125074

RESUMO

The microbial safety concern associated with thermally processed extended shelf life (ESL) refrigerated foods is based on adequate elimination of spore-forming pathogens such as nonproteolytic Clostridium botulinum types B, E, and F. These pathogens are traditionally regarded as targets for validation of thermally processed ESL foods. However, their use for research is restricted due to their designation as select agents. In this study, the thermal resistances of spores of 10 nonproteolytic C. botulinum types B and F and seven psychrotrophic Bacillus cereus strains were evaluated in ACES (N-(2-acetamido)-2-aminoethanesulfonic acid) buffer (0.05 M, pH 7.00) and compared to determine whether any of the B. cereus strains could serve as a nonselect agent for establishing thermal processes for ESL refrigerated foods. Thermal decimal reduction times (DT-values) of both nonproteolytic C. botulinum types B and F and psychrotrophic B. cereus strains decreased as process temperature increased from 80 to 91°C, and the highest values were obtained at 80°C. All psychrotrophic B. cereus strains tested were more thermally resistant than nonproteolytic C. botulinum types B and F. DT-values of nonproteolytic C. botulinum types B and F decreased to <1.0 min at 87°C, whereas all psychrotrophic B. cereus strains had higher DT-values (i.e., 52.35 to 133.69 min) at the same temperature. Among all psychrotrophic B. cereus strains tested, BC-6A16 had the highest DT-values at any given temperature. The DT-values indicated that the psychrotrophic B. cereus strains were more thermally resistant than the nonproteolytic C. botulinum strains and therefore may be potential target pathogens for thermal process validation of ESL refrigerated foods. However, further comparative challenge studies are needed with a model food system or an ESL refrigerated food to confirm these results.


Assuntos
Bacillus cereus , Clostridium botulinum , Microbiologia de Alimentos , Temperatura Alta , Esporos Bacterianos
14.
J R Soc Med ; 113(3): 110-118, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32160121

RESUMO

OBJECTIVES: Research suggests that antisocial lifestyles constitute significant health risks. However, there are marked individual differences in the stability of antisocial behaviour. These different offending pathways may bear differential risks for adult health. DESIGN: Injury and illness data were collected prospectively in the longitudinal Cambridge Study in Delinquent Development. SETTING: Working-class inner-city area of South London. PARTICIPANTS: Participants included the 411 men from the Cambridge Study in Delinquent Development, with interview data collected at ages 18, 32 and 48 years for each individual. MAIN OUTCOME MEASURES: Organic illness, hospitalisation and injuries. RESULTS: By age 48, adjusted odds ratios showed that the incidence of organic illness was higher among Life-Course-Persistent, Late-Onset offenders and offenders in general. Based on adjusted odds ratios at age 32, the incidence of hospitalisations was higher for Late-Onset offenders. Adjusted odds ratios at age 48 also showed that the incidence of hospitalisations was higher for all three offender types and offenders in general. Our results also provide evidence that offenders were more likely to suffer injuries than non-offenders. CONCLUSIONS: The findings of this study imply that preventing individuals from offending is likely to have substantial benefits for health.


Assuntos
Transtorno da Personalidade Antissocial/epidemiologia , Crime/estatística & dados numéricos , Criminosos/estatística & dados numéricos , Estilo de Vida , Saúde Mental , Admissão do Paciente/tendências , Medição de Risco , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Incidência , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Meio Social , Adulto Jovem
15.
Proc Math Phys Eng Sci ; 476(2242): 20200319, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33214761

RESUMO

We propose an extension of the axial next nearest neighbour Ising (ANNNI) model to a general number of interactions between spins. We apply this to the calculation of stacking fault energies in magnesium-particularly challenging due to the long-ranged screening of the pseudopotential by the free electron gas. We employ both density functional theory (DFT) using highest possible precision, and generalized pseudopotential theory (GPT) in the form of an analytic, long ranged, oscillating pair potential. At the level of first neighbours, the Ising model is reasonably accurate, but higher order terms are required. In fact, our ' AN N NI model' is slow to converge-an inevitable feature of the free electron-like electronic structure. In consequence, the convergence and internal consistency of the AN N NI model is problematic within the most precise implementation of DFT. The GPT shows the convergence and internal consistency of the DFT bandstructure approach with electron temperature, but does not lead to loss of precision. The GPT is as accurate as a full implementation of DFT but carries the additional benefit that damping of the oscillations in the AN N NI model parameters are achieved without entailing error in stacking fault energies. We trace this to the logarithmic singularity of the Lindhard function.

16.
Clin Infect Dis ; 47(10): 1245-51, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18834318

RESUMO

BACKGROUND: On 8 September 2006, 3 Georgia residents presented with symptoms of food-borne botulism, a potentially fatal illness caused by Clostridium botulinum neurotoxins. METHODS: Investigators reviewed medical records and interviewed patients and family members. Foods from patients' homes and samples of the implicated commercial beverage were tested for botulinum toxin and C. botulinum by standard methods. RESULTS: The patients presented with cranial neuropathies and flaccid paralysis; all patients required mechanical ventilation. The 3 Georgia patients had consumed carrot juice from the same bottle before illness onset. An additional case in Florida and 2 in Ontario, Canada, were subsequently identified in patients who had consumed carrot juice. Serum samples obtained from 5 patients tested positive for botulinum toxin type A-in one patient, 12 days after illness onset, and in another patient, 25 days after illness onset. Carrot juice produced by 1 manufacturer, recovered from patients' homes in Georgia, Florida, and Ontario, yielded type A toxin. The juice contained no added sugar, salt, or preservative; inappropriate refrigeration likely resulted in botulinum toxin production. CONCLUSION: This outbreak was caused by commercially produced, internationally distributed carrot juice that was contaminated with botulinum toxin. When toxemia persists, treatment for botulism should be considered even if diagnosed weeks after illness onset. The implicated pasteurized carrot juice had no barriers to growth of C. botulinum other than refrigeration; additional protective measures for carrot juice are needed to prevent future outbreaks. The US Food and Drug Administration has since issued industry guidance to reduce the risk of C. botulinum intoxication from low-acid refrigerated juices.


Assuntos
Botulismo/epidemiologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Toxemia , Toxinas Botulínicas Tipo A/sangue , Botulismo/fisiopatologia , Florida/epidemiologia , Análise de Alimentos , Doenças Transmitidas por Alimentos/fisiopatologia , Georgia/epidemiologia , Humanos , Ontário/epidemiologia
18.
J Food Prot ; 81(2): 261-271, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29360398

RESUMO

The impact of high pressure processing on the inactivation of spores of nonproteolytic Clostridium botulinum is important in extended shelf life chilled low-acid foods. The three most resistant C. botulinum strains (Ham-B, Kap 9-B, and 610-F) were selected for comparison of their thermal and pressure-assisted thermal resistance after screening 17 nonproteolytic C. botulinum strains (8 type B, 7 type E, and 2 type F). Spores of strains Ham-B, Kap 9-B, and 610-F were prepared using a biphasic media method, diluted in N-(2-acetamido)-2-aminoethanesulfonic acid (ACES) buffer (0.05 M, pH 7.00) to 105 to 106 CFU/mL, placed into a modified sterile transfer pipette, heat sealed, and subjected to a combination of high pressures (600 to 750 MPa) and high temperatures (80 to 91°C) using laboratory and pilot-scale pressure test systems. Diluted spores from the same crops were placed in nuclear magnetic resonance tubes, which were heat sealed, and subjected to 80 to 91°C in a Fluke 7321 high precision bath with Duratheram S oil as the heat transfer fluid. After incubation for 3 months, survivors in both studies were determined by the five-tube most-probable-number method using Trypticase-peptone-glucose-yeast extract broth. The highest (>5.0) log reductions in spore counts for Ham-B, Kap 9-B, and 610-F occurred at the highest temperature and pressure combination tested (91°C and 750 MPa). Thermal D-values of Ham-B, Kap 9-B, and 610-F decreased as the process temperature increased from 80 to 87°C, decreasing to <1.0 min at 87°C for these strains. Pressure-assisted thermal D-values of Ham-B, Kap 9-B, and 610-F decreased as the process temperature increased from 80 to 91°C with any pressure combination and decreased to <1.0 min as the pressure increased from 600 to 750 MPa at 91°C. Based on the pressure-assisted thermal D-values, pressure exerted a more protective effect on spores of Ham-B, Kap 9-B, and 610-F when processed at 83 to 91°C combined with pressures of 600 to 700 MPa when compared with thermal treatment only. No protective effect was observed when the spores of Ham-B, Kap9-B, and 610-F were treated at lower temperatures (80 to 83°C) in combination with 750 MPa. However, at higher temperatures (87 to 91°C) in combination with 750 MPa, a protective effect was seen for Ham-B, Kap9-B, and 610-F spores based on the calculated pressure-assisted thermal D-values.


Assuntos
Clostridium botulinum/fisiologia , Temperatura Alta , Pressão , Esporos Bacterianos/fisiologia
19.
Genome Announc ; 6(26)2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29954889

RESUMO

Clostridium botulinum is a strictly anaerobic, Gram-positive, spore-forming bacterium that produces botulinum neurotoxin, a potent and deadly proteinaceous exotoxin. Clostridium botulinum strain CFSAN064329 (62A) produces an A1 serotype/subtype botulinum neurotoxin and is frequently utilized in food challenge and detection studies. We report here the closed genome sequence of Clostridium botulinum strain CFSAN064329 (62A).

20.
Philos Trans A Math Phys Eng Sci ; 375(2098)2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28607196

RESUMO

This session concerned the political, economic and environmental impact on the hydrogen economy due to hydrogen embrittlement.This article is part of the themed issue 'The challenges of hydrogen and metals'.

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