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1.
J Infect Dis ; 229(3): 733-742, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-37925626

RESUMO

Nipah virus Bangladesh (NiVB) is a bat-borne zoonosis transmitted between people through the respiratory route. The risk posed by related henipaviruses, including Hendra virus (HeV) and Nipah virus Malaysia (NiVM), is less clear. We conducted a broad search of the literature encompassing both human infections and animal models to synthesize evidence about potential for person-to-person spread. More than 600 human infections have been reported in the literature, but information on viral shedding was only available for 40 case-patients. There is substantial evidence demonstrating person-to-person transmission of NiVB, and some evidence for NiVM. Less direct evidence is available about the risk for person-to-person transmission of HeV, but animals infected with HeV shed more virus in the respiratory tract than those infected with NiVM, suggesting potential for transmission. As the group of known henipaviruses continues to grow, shared protocols for conducting and reporting from human investigations and animal experiments are urgently needed.


Assuntos
Vírus Hendra , Infecções por Henipavirus , Vírus Nipah , Animais , Humanos , Infecções por Henipavirus/transmissão , Malásia , Zoonoses/transmissão
2.
Emerg Infect Dis ; 30(2): 376-379, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38232709

RESUMO

During May 2022-April 2023, dengue virus serotype 3 was identified among 601 travel-associated and 61 locally acquired dengue cases in Florida, USA. All 203 sequenced genomes belonged to the same genotype III lineage and revealed potential transmission chains in which most locally acquired cases occurred shortly after introduction, with little sustained transmission.


Assuntos
Vírus da Dengue , Dengue , Humanos , Vírus da Dengue/genética , Dengue/epidemiologia , Florida/epidemiologia , Viagem , Sequência de Bases , Genótipo , Sorogrupo , Filogenia
3.
MMWR Morb Mortal Wkly Rep ; 73(35): 763-768, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39236025

RESUMO

Leptospirosis, an acute bacterial zoonotic disease, is endemic in Puerto Rico. Infection in approximately 10%-15% of patients with clinical disease progresses to severe, potentially fatal illness. Increased incidence has been associated with flooding in endemic areas around the world. In 2022, Hurricane Fiona, a Category 1 hurricane, made landfall and inundated Puerto Rico with heavy rainfall and severe flooding, increasing the risk for a leptospirosis outbreak. In response, the Puerto Rico Department of Health (PRDH) changed guidelines to make leptospirosis cases reportable within 24 hours, centralized the case investigation management system, and provided training and messaging to health care providers. To evaluate changes in risk for leptospirosis after Hurricane Fiona to that before the storm, the increase in cases was quantified, and patient characteristics and geographic distribution were compared. During the 15 weeks after Hurricane Fiona, 156 patients experienced signs and symptoms of leptospirosis and had a specimen with a positive laboratory result reported to PRDH. The mean weekly number of cases during this period was 10.4, which is 3.6 as high as the weekly number of cases during the previous 37 weeks (2.9). After Hurricane Fiona, the proportion of cases indicating exposure to potentially contaminated water increased from 11% to 35%, and the number of persons receiving testing increased; these factors likely led to the resulting overall surge in reported cases. Robust surveillance combined with outreach to health care providers after flooding events can improve leptospirosis case identification, inform clinicians considering early initiation of treatment, and guide public messaging to avoid wading, swimming, or any contact with potentially contaminated floodwaters.


Assuntos
Tempestades Ciclônicas , Surtos de Doenças , Leptospirose , Porto Rico/epidemiologia , Leptospirose/epidemiologia , Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Criança , Idoso , Pré-Escolar , Desastres
4.
Inj Prev ; 29(1): 85-90, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36301795

RESUMO

Introduction Non-fatal shooting rates vary tremendously within cities in the USA. Factors related to structural racism (both historical and contemporary) could help explain differences in non-fatal shooting rates at the neighbourhood level. Most research assessing the relationship between structural racism and firearm violence only includes one dimension of structural racism. Our study uses an intersectional approach to examine how the interaction of two forms of structural racism is associated with spatial non-fatal shooting disparities in Baltimore, Maryland. Methods We present three additive interaction measures to describe the relationship between historical redlining and contemporary racialized economic segregation on neighbourhood-level non-fatal shootings. Results Our findings revealed that sustained disadvantage census tracts (tracts that experience contemporary socioeconomic disadvantage and were historically redlined) have the highest burden of non-fatal shootings. Sustained disadvantage tracts had on average 24 more non-fatal shootings a year per 10 000 residents compared with similarly populated sustained advantage tracts (tracts that experience contemporary socioeconomic advantage and were not historically redlined). Moreover, we found that between 2015 and 2019, the interaction between redlining and racialized economic segregation explained over one-third of non-fatal shootings (approximately 650 shootings) in sustained disadvantage tracts. Conclusion These findings suggest that the intersection of historical and contemporary structural racism is a fundamental cause of firearm violence inequities in Baltimore. Intersectionality can advance injury prevention research and practice by (1) serving as an analytical tool to expose inequities in injury-related outcomes and (2) informing the development and implementation of injury prevention interventions and policies that prioritise health equity and racial justice.


Assuntos
Armas de Fogo , Racismo Sistêmico , Humanos , Baltimore/epidemiologia , Enquadramento Interseccional , Características de Residência
5.
Emerg Infect Dis ; 27(6): 1598-1606, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34013872

RESUMO

Relatively few coronavirus disease cases and deaths have been reported from sub-Saharan Africa, although the extent of its spread remains unclear. During August 10-September 11, 2020, we recruited 2,214 participants for a representative household-based cross-sectional serosurvey in Juba, South Sudan. We found 22.3% of participants had severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain IgG titers above prepandemic levels. After accounting for waning antibody levels, age, and sex, we estimated that 38.3% (95% credible interval 31.8%-46.5%) of the population had been infected with SARS-CoV-2. At this rate, for each PCR-confirmed SARS-CoV-2 infection reported by the Ministry of Health, 103 (95% credible interval 86-126) infections would have been unreported, meaning SARS-CoV-2 has likely spread extensively within Juba. We also found differences in background reactivity in Juba compared with Boston, Massachusetts, USA, where the immunoassay was validated. Our findings underscore the need to validate serologic tests in sub-Saharan Africa populations.


Assuntos
COVID-19 , SARS-CoV-2 , África Subsaariana , Anticorpos Antivirais , Boston , Estudos Transversais , Humanos , Imunoglobulina G , Massachusetts , Estudos Soroepidemiológicos , Sudão do Sul
6.
Am J Epidemiol ; 190(10): 2085-2093, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34023892

RESUMO

Administration of many childhood vaccines requires that multiple doses be delivered within a narrow time window to provide adequate protection and reduce disease transmission. Accurately quantifying vaccination coverage is complicated by limited individual-level data and multiple vaccination mechanisms (routine and supplementary vaccination programs). We analyzed 12,541 vaccination cards from 6 districts across Madagascar for children born in 2015 and 2016. For 3 vaccines-pentavalent diphtheria-tetanus-pertussis-hepatitis B-Haemophilus influenzae type b vaccine (DTP-HB-Hib; 3 doses), 10-valent pneumococcal conjugate vaccine (PCV10; 3 doses), and rotavirus vaccine (2 doses)-we used dates of vaccination and birth to estimate coverage at 1 year of age and timeliness of delivery. Vaccination coverage at age 1 year for the first dose was consistently high, with decreases for subsequent doses (DTP-HB-Hib: 91%, 81%, and 72%; PCV10: 82%, 74%, and 64%; rotavirus: 73% and 63%). Coverage levels between urban districts and their rural counterparts did not differ consistently. For each dose of DTP-HB-Hib, the overall percentage of individuals receiving late doses was 29%, 7%, and 6%, respectively; estimates were similar for other vaccines. Supplementary vaccination weeks, held to help children who had missed routine care to catch up, did not appear to increase the likelihood of being vaccinated. Maintaining population-level immunity with multiple-dose vaccines requires a robust stand-alone routine immunization program.


Assuntos
Programas de Imunização/estatística & dados numéricos , Saúde da População/estatística & dados numéricos , Cobertura Vacinal/estatística & dados numéricos , Vacinas/administração & dosagem , Pré-Escolar , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Feminino , Vacinas Anti-Haemophilus/administração & dosagem , Humanos , Esquemas de Imunização , Lactente , Madagáscar , Masculino , Vacinas Pneumocócicas/administração & dosagem , Vacinas contra Rotavirus/administração & dosagem , Cobertura Vacinal/métodos
7.
Theor Appl Genet ; 134(7): 2167-2179, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33774682

RESUMO

KEY MESSAGE: A new gene Rph28 conferring resistance to barley leaf rust was discovered and fine-mapped on chromosome 5H from wild barley. Leaf rust is a highly destructive disease of barley caused by the fungal pathogen Puccinia hordei. Genetic resistance is considered to be the most effective, economical and eco-friendly approach to minimize losses caused by this disease. A study was undertaken to characterize and fine map a seedling resistance gene identified in a Hordeum vulgare ssp. spontaneum-derived barley line, HEB-04-101, that is broadly effective against a diverse set of Australian P. hordei pathotypes. Genetic analysis of an F3 population derived from a cross between HEB-04-101 and the H. vulgare cultivar Flagship (seedling susceptible) confirmed the presence of a single dominant gene for resistance in HEB-04-101. Selective genotyping was performed on representative plants from non-segregating homozygous resistant and homozygous susceptible F3 families using the targeted genotyping-by-sequencing (tGBS) assay. Putatively linked SNP markers with complete fixation were identified on the long arm of chromosome 5H spanning a physical interval between 622 and 669 Mb based on the 2017 Morex barley reference genome assembly. Several CAPS (cleaved amplified polymorphic sequences) markers were designed from the pseudomolecule sequence of the Morex assembly (v1.0 and v2.0), and 16 polymorphic markers were able to delineate the RphHEB locus to a 0.05 cM genetic interval spanning 98.6 kb. Based on its effectiveness and wild origin, RphHEB is distinct from all other designated Rph genes located on chromosome 5H and therefore the new locus symbol Rph28 is recommended for RphHEB in accordance with the rules and cataloguing system of barley gene nomenclature.


Assuntos
Resistência à Doença/genética , Hordeum/genética , Doenças das Plantas/genética , Puccinia/patogenicidade , Mapeamento Cromossômico , Cruzamentos Genéticos , Genes de Plantas , Marcadores Genéticos , Genótipo , Hordeum/microbiologia , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único
8.
Ann Intern Med ; 172(9): 577-582, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150748

RESUMO

BACKGROUND: A novel human coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in China in December 2019. There is limited support for many of its key epidemiologic features, including the incubation period for clinical disease (coronavirus disease 2019 [COVID-19]), which has important implications for surveillance and control activities. OBJECTIVE: To estimate the length of the incubation period of COVID-19 and describe its public health implications. DESIGN: Pooled analysis of confirmed COVID-19 cases reported between 4 January 2020 and 24 February 2020. SETTING: News reports and press releases from 50 provinces, regions, and countries outside Wuhan, Hubei province, China. PARTICIPANTS: Persons with confirmed SARS-CoV-2 infection outside Hubei province, China. MEASUREMENTS: Patient demographic characteristics and dates and times of possible exposure, symptom onset, fever onset, and hospitalization. RESULTS: There were 181 confirmed cases with identifiable exposure and symptom onset windows to estimate the incubation period of COVID-19. The median incubation period was estimated to be 5.1 days (95% CI, 4.5 to 5.8 days), and 97.5% of those who develop symptoms will do so within 11.5 days (CI, 8.2 to 15.6 days) of infection. These estimates imply that, under conservative assumptions, 101 out of every 10 000 cases (99th percentile, 482) will develop symptoms after 14 days of active monitoring or quarantine. LIMITATION: Publicly reported cases may overrepresent severe cases, the incubation period for which may differ from that of mild cases. CONCLUSION: This work provides additional evidence for a median incubation period for COVID-19 of approximately 5 days, similar to SARS. Our results support current proposals for the length of quarantine or active monitoring of persons potentially exposed to SARS-CoV-2, although longer monitoring periods might be justified in extreme cases. PRIMARY FUNDING SOURCE: U.S. Centers for Disease Control and Prevention, National Institute of Allergy and Infectious Diseases, National Institute of General Medical Sciences, and Alexander von Humboldt Foundation.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Período de Incubação de Doenças Infecciosas , Pneumonia Viral/transmissão , Adulto , COVID-19 , China , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
9.
Epidemiol Infect ; 148: e283, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33190665

RESUMO

Pertussis is a highly contagious infectious disease and remains an important cause of mortality and morbidity worldwide. Over the last decade, vaccination has greatly reduced the burden of pertussis. Yet, uncertainty in individual vaccination coverage and ineffective case surveillance systems make it difficult to estimate burden and the related quantity of population-level susceptibility, which determines population risk. These issues are more pronounced in low-income settings where coverage is often overestimated, and case numbers are under-reported. Serological data provide a direct characterisation of the landscape of susceptibility to infection; and can be combined with vaccination coverage and basic theory to estimate rates of exposure to natural infection. Here, we analysed cross-sectional data on seropositivity against pertussis to identify spatial and age patterns of susceptibility in children in Madagascar. A large proportion of individuals surveyed were seronegative; however, there were patterns suggestive of natural infection in all the regions analysed. Improvements in vaccination coverage are needed to help prevent additional burden of pertussis in the country.


Assuntos
Vacina contra Coqueluche/imunologia , Estudos Soroepidemiológicos , Coqueluche/epidemiologia , Coqueluche/prevenção & controle , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Madagáscar/epidemiologia , Fatores de Tempo , Vacinação
12.
Proc Natl Acad Sci U S A ; 113(18): 5107-12, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27091978

RESUMO

Every year in the United States more than 12,000 women are diagnosed with cervical cancer, a disease principally caused by human papillomavirus (HPV). Bivalent and quadrivalent HPV vaccines protect against 66% of HPV-associated cervical cancers, and a new nonavalent vaccine protects against an additional 15% of cervical cancers. However, vaccination policy varies across states, and migration between states interdependently dilutes state-specific vaccination policies. To quantify the economic and epidemiological impacts of switching to the nonavalent vaccine both for individual states and for the nation as a whole, we developed a model of HPV transmission and cervical cancer incidence that incorporates state-specific demographic dynamics, sexual behavior, and migratory patterns. At the national level, the nonavalent vaccine was shown to be cost-effective compared with the bivalent and quadrivalent vaccines at any coverage despite the greater per-dose cost of the new vaccine. Furthermore, the nonavalent vaccine remains cost-effective with up to an additional 40% coverage of the adolescent population, representing 80% of girls and 62% of boys. We find that expansion of coverage would have the greatest health impact in states with the lowest coverage because of the decreasing marginal returns of herd immunity. Our results show that if policies promoting nonavalent vaccine implementation and expansion of coverage are coordinated across multiple states, all states benefit both in health and in economic terms.


Assuntos
Efeitos Psicossociais da Doença , Vacinação em Massa/economia , Infecções por Papillomavirus/economia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/economia , Vacinas contra Papillomavirus/uso terapêutico , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Análise Custo-Benefício/economia , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Vacinação em Massa/estatística & dados numéricos , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Prevalência , Medição de Risco , Distribuição por Sexo , Estados Unidos/epidemiologia , Adulto Jovem
13.
Proc Natl Acad Sci U S A ; 113(46): 13239-13244, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27799521

RESUMO

Respiratory syncytial virus (RSV) is the most common cause of US infant hospitalization. Additionally, RSV is responsible for 10,000 deaths annually among the elderly across the United States, and accounts for nearly as many hospitalizations as influenza. Currently, several RSV vaccine candidates are under development to target different age groups. To evaluate the potential effectiveness of age-specific vaccination strategies in averting RSV incidence, we developed a transmission model that integrates data on daily infectious viral load and changes of behavior associated with RSV symptoms. Calibrating to RSV weekly incidence rates in Texas, California, Colorado, and Pennsylvania, we show that in all states considered, an infected child under 5 y of age is more than twice as likely as a person over 50 y of age to transmit the virus. Geographic variability in the effectiveness of a vaccination program across states arises from interplay between seasonality patterns, population demography, vaccination uptake, and vaccine mechanism of action. Regardless of these variabilities, our analysis showed that allocating vaccine to children under 5 y of age would be the most efficient strategy per dose to avert RSV in both children and adults. Furthermore, due to substantial indirect protection, the targeting of children is even predicted to reduce RSV in the elderly more than directly vaccinating the elderly themselves. Our results can help inform ongoing clinical trials and future recommendations on RSV vaccination.


Assuntos
Modelos Teóricos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Infecções por Vírus Respiratório Sincicial/transmissão , Vírus Sincicial Respiratório Humano/imunologia , Estados Unidos/epidemiologia , Adulto Jovem
14.
Plant Dis ; 103(11): 2798-2803, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31524094

RESUMO

Barley yellow dwarf (BYD) is a major virus disease which dramatically reduces wheat yield. Introducing BYD resistance genes into commercial varieties has been proven to be effective in reducing damage caused by barley yellow dwarf virus (BYDV). However, only one major resistance gene is readily deployable for breeding; Bdv2 derived from Thinopyrum intermedium is deployed as a chromosomal translocation. In this study, a double haploid (DH) population was developed from a cross between XuBYDV (introduced from China showing very good resistance to BYD) and H-120 (a BYD-sensitive Chinese accession), and was used to identify QTL for BYD resistance. The population was genotyped using an Infinium iSelect bead chip array targeting 90K gene-based SNPs. The disease resistance of DH lines inoculated with BYDV was assessed at the heading stage. The infections were assessed by tissue blot immunoassay (TBIA). Three new QTL were identified on chromosomes 5A, 6A, and 7A for both symptom and TBIA, with all three resistance alleles being inherited from XuBYDV. Some DH lines with the resistance alleles from all three QTL showed high level resistance to BYD. These new QTL will be useful in breeding programs for pyramiding BYD resistance genes.


Assuntos
Resistência à Doença , Luteovirus , Locos de Características Quantitativas , Triticum , China , Resistência à Doença/genética , Luteovirus/fisiologia , Doenças das Plantas/virologia , Triticum/genética , Triticum/virologia
16.
Br J Anaesth ; 120(2): 264-273, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29406175

RESUMO

Competency-based assessment tools are used in regional anaesthesia to measure the performance of study participants, trainees, and consultants. This narrative review was performed to appraise currently published assessment tools for regional anaesthesia. A literature search found 397 citations of which 28 peer-reviewed studies met the inclusion criteria of primary psychometric evaluation of assessment tools for regional anaesthesia. The included studies were diverse in the type of assessment and the skill set being assessed. The types of assessments included multiple-choice questions, hand-motion analysis, cumulative sum, visuospatial and psychomotor screening, checklists, and global rating scales. The skill sets that were assessed included holistic regional anaesthesia technical and non-technical performance observed at the bedside, to isolated part-tasks, such as needle tip visualisation under ultrasound. To evaluate validity and reliability, we compared the studies against published medical education consensus statements on ideal assessment tools. We discuss the relative merits of different tools when used to assess regional anaesthesia, the importance of psychometrically robust assessment tools in competency-based anaesthesia education, and directions for future education research in regional anaesthesia.


Assuntos
Anestesia por Condução/normas , Anestesiologia/normas , Competência Clínica/normas , Anestesia por Condução/métodos , Anestesiologia/educação , Avaliação Educacional , Humanos , Psicometria , Reprodutibilidade dos Testes
17.
Emerg Infect Dis ; 22(5): 875-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27088272

RESUMO

Flooding on 1 of the Solomon Islands precipitated a nationwide epidemic of diarrhea that spread to regions unaffected by flooding and caused >6,000 cases and 27 deaths. Rotavirus was identified in 38% of case-patients tested in the city with the most flooding. Outbreak potential related to weather reinforces the need for global rotavirus vaccination.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Surtos de Doenças , Inundações , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Melanesia/epidemiologia , Filogenia , Vigilância da População , Prevalência , Rotavirus/classificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/transmissão
18.
Anaesthesia ; 71(8): 921-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26993374

RESUMO

The aim of this prospective, blinded, randomised controlled study was to compare novices' acquisition of the technical skills of ultrasound-guided regional anaesthesia using either a meat phantom model or fresh-frozen human cadavers. The primary outcome was the time taken to successfully perform an ultrasound-guided sciatic nerve block on a cadaver; secondary outcomes were the cumulative score of errors, and best image quality of the sciatic nerve achieved. After training, the median (IQR [range]) time taken to perform the block was 311(164-390 [68-600]) s in the meat model trained group and 210 (174-354 [85-600]) s in the fresh-frozen cadaver trained group (p = 0.24). Participants made a median (IQR [range]) of 18 (14-33 [8-55]) and 15 (12-22 [8-44]) errors in the two groups respectively (p = 0.39). The image quality score was also not different, with a median (IQR [range]) of 62.5 (59.4-65.6 [25.0-100.0])% vs 62.5 (62.5-75.0 [25.0-87.5])% respectively (p = 0.58). The training and deliberate feedback improved all participants' block performance, the median (IQR [range]) times being 310 (206-532 [110-600]) s before and 240 (174-354 [85-600]) s after training (p = 0.02). We conclude that novices taught ultrasound scanning and needle guidance skills using an inexpensive and easily constructed meat model perform similarly to those trained on a cadaveric model.


Assuntos
Anestesiologia/educação , Bloqueio Nervoso/métodos , Ultrassonografia de Intervenção/métodos , Cadáver , Competência Clínica , Feminino , Humanos , Masculino , Estudos Prospectivos , Ensino
19.
PLoS Pathog ; 9(10): e1003709, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130500

RESUMO

In an effort to suppress microbial outgrowth, the host sequesters essential nutrients in a process termed nutritional immunity. However, inflammatory responses to bacterial insult can restore nutritional resources. Given that nutrient availability modulates virulence factor production and biofilm formation by other bacterial species, we hypothesized that fluctuations in heme-iron availability, particularly at privileged sites, would similarly influence Haemophilus biofilm formation and pathogenesis. Thus, we cultured Haemophilus through sequential heme-iron deplete and heme-iron replete media to determine the effect of transient depletion of internal stores of heme-iron on multiple pathogenic phenotypes. We observed that prior heme-iron restriction potentiates biofilm changes for at least 72 hours that include increased peak height and architectural complexity as compared to biofilms initiated from heme-iron replete bacteria, suggesting a mechanism for epigenetic responses that participate in the changes observed. Additionally, in a co-infection model for human otitis media, heme-iron restricted Haemophilus, although accounting for only 10% of the inoculum (90% heme-iron replete), represented up to 99% of the organisms recovered at 4 days. These data indicate that fluctuations in heme-iron availability promote a survival advantage during disease. Filamentation mediated by a SulA-related ortholog was required for optimal biofilm peak height and persistence during experimental otitis media. Moreover, severity of disease in response to heme-iron restricted Haemophilus was reduced as evidenced by lack of mucosal destruction, decreased erythema, hemorrhagic foci and vasodilatation. Transient restriction of heme-iron also promoted productive invasion events leading to the development of intracellular bacterial communities. Taken together, these data suggest that nutritional immunity, may, in fact, foster long-term phenotypic changes that better equip bacteria for survival at infectious sites.


Assuntos
Biofilmes , Epigênese Genética , Infecções por Haemophilus/metabolismo , Haemophilus/fisiologia , Heme/metabolismo , Ferro/metabolismo , Otite Média/metabolismo , Animais , Chinchila , Modelos Animais de Doenças , Infecções por Haemophilus/genética , Infecções por Haemophilus/imunologia , Infecções por Haemophilus/patologia , Heme/genética , Heme/imunologia , Humanos , Ferro/imunologia , Otite Média/genética , Otite Média/imunologia , Otite Média/microbiologia , Otite Média/patologia , Índice de Gravidade de Doença , Fatores de Tempo
20.
Anaesthesia ; 70(12): 1401-11, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26558857

RESUMO

The aim of this study was to create and evaluate the validity, reliability and feasibility of the Regional Anaesthesia Procedural Skills tool, designed for the assessment of all peripheral and neuraxial blocks using all nerve localisation techniques. The first phase was construction of a 25-item checklist by five regional anaesthesia experts using a Delphi process. This checklist was combined with a global rating scale to create the tool. In the second phase, initial validation by 10 independent anaesthetists using a test-retest methodology was successful (Cohen kappa ≥ 0.70 for inter-rater agreement, scores between test to retest, paired t-test, p > 0.12). In the third phase, 70 clinical videos of trainees were scored by three blinded international assessors. The RAPS tool exhibited face validity (p < 0.026), construct validity (p < 0.001), feasibility (mean time to score < 3.9 min), and overall reliability (intraclass correlation coefficient 0.80 (95% CI 0.67-0.88)). The Regional Anaesthesia Procedural Skills tool used in this study is a valid and reliable assessment tool to score the performance of trainees for regional anaesthesia.


Assuntos
Anestesiologia/educação , Competência Clínica , Avaliação Educacional , Bloqueio Nervoso/métodos , Lista de Checagem , Humanos
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