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1.
PLoS One ; 19(2): e0298335, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38421960

RESUMO

BACKGROUND: Bathing babies less frequently and intensively in the first six months of life may prevent eczema, but this has not yet been definitively tested in a randomised controlled trial. Such a trial would require evidence-based support to help parents engage with a minimal bathing routine. The present study reports the development of this support. METHODS: We adopted a four-stage design process: (i) Pregnant women and their families (n = 31) were interviewed to ascertain key barriers and facilitators towards following the minimal bathing intervention. (ii) These barriers and facilitators were mapped to behaviour change techniques, focussing on the intervention types of education, persuasion and environmental restructuring, alongside appropriate modes of delivery, and prototype intervention materials were developed. (iii) We iteratively refined these materials in a workshop with multidisciplinary experts and Patient and Public Involvement and Engagement (PPIE) representatives (n = 13) and an (iv) intervention walkthrough with families (n = 5). The design process was informed by the Behaviour Change Wheel, Theoretical framework of acceptability and the Template for intervention description and replication. RESULTS: Social influences and motivational factors are likely to influence both uptake and adherence to the intervention. Anticipated emotional reward from participating in research for the benefit of others was indicated to be a strong facilitator for intervention uptake. Alternatives to bathing, having fun with the baby and the night-time routine, alongside family support, were notable facilitators suggested to aid adherence to the intervention. Barriers included hygiene concerns and anticipated negative social appraisal. Barriers and facilitators were mapped to thirty-six behaviour change techniques, focussing on the intervention types of education, persuasion and environmental restructuring, all of which were embedded into the package of support. The prototype intervention materials received positive feedback from the expert workshop and study walkthrough with families. The final package of support comprises printed and digital prompts and cues, a study booklet, video, and digital tool for self-monitoring. CONCLUSIONS: The intervention design process incorporated the 'real world' views and experiences of families, experts and PPIE representatives, alongside criteria for designing behavioural interventions. The effectiveness of the package of support will be tested in a feasibility trial and embedded process evaluation.


Assuntos
Terapia Comportamental , Eczema , Feminino , Humanos , Lactente , Gravidez , Sinais (Psicologia)
2.
BMJ Open ; 13(11): e075558, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968006

RESUMO

INTRODUCTION: The English National Health Service (NHS) Diabetic Eye Screening Programme (DESP) performs around 2.3 million eye screening appointments annually, generating approximately 13 million retinal images that are graded by humans for the presence or severity of diabetic retinopathy. Previous research has shown that automated retinal image analysis systems, including artificial intelligence (AI), can identify images with no disease from those with diabetic retinopathy as safely and effectively as human graders, and could significantly reduce the workload for human graders. Some algorithms can also determine the level of severity of the retinopathy with similar performance to humans. There is a need to examine perceptions and concerns surrounding AI-assisted eye-screening among people living with diabetes and NHS staff, if AI was to be introduced into the DESP, to identify factors that may influence acceptance of this technology. METHODS AND ANALYSIS: People living with diabetes and staff from the North East London (NEL) NHS DESP were invited to participate in two respective focus groups to codesign two online surveys exploring their perceptions and concerns around the potential introduction of AI-assisted screening.Focus group participants were representative of the local population in terms of ages and ethnicity. Participants' feedback was taken into consideration to update surveys which were circulated for further feedback. Surveys will be piloted at the NEL DESP and followed by semistructured interviews to assess accessibility, usability and to validate the surveys.Validated surveys will be distributed by other NHS DESP sites, and also via patient groups on social media, relevant charities and the British Association of Retinal Screeners. Post-survey evaluative interviews will be undertaken among those who consent to participate in further research. ETHICS AND DISSEMINATION: Ethical approval has been obtained by the NHS Research Ethics Committee (IRAS ID: 316631). Survey results will be shared and discussed with focus groups to facilitate preparation of findings for publication and to inform codesign of outreach activities to address concerns and perceptions identified.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Medicina Estatal , Inteligência Artificial , Atenção Secundária à Saúde , Programas de Rastreamento/métodos , Diabetes Mellitus/diagnóstico
3.
Clin Exp Rheumatol ; 41(8): 1578-1588, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36826808

RESUMO

OBJECTIVES: The early gastrointestinal (GI) manifestation of systemic sclerosis (SSc) suggests a possible GI microbiota engagement in the pathophysiology and/or progression of SSc. Previous studies have revealed dysbiosis among Caucasian SSc patients. This study extends these findings to Asian SSc patients. METHODS: Adult SSc patients, stratified according to 1) on immunosuppressive (On-IS) drugs or 2) no immunosuppressive drugs (No-IS), and age-and-sex-matched healthy controls (HC) were recruited. Metagenomic sequencing of stool DNA was compared between SSc patients and HC, and between SSc (On-IS) and (No-IS) patients. Alpha and beta-diversity, taxonomic and functional profiling were evaluated. RESULTS: Twenty-three female SSc patients (12 On-IS; 11 No-IS; 5 diffuse and 18 limited SSc subtype) and 19 female HC, with median age of 54 years and 56 years, respectively, were recruited. Median SSc disease duration was 3.3 years. Alpha diversity was significantly higher in SSc versus HC (p=0.014) and in SSc (No-IS) versus HC (p=0.006). There was no significant difference in beta diversity between SSc and HC (p=0.307). At the phyla level, there were significantly increased abundance of Firmicutes and Actinobacteria in SSc versus HC, and reduced abundance of Bacteroidetes (all p<0.001). At the species level, there were significantly increased abundance of several Lactobacillus, Bifidobacterium, and Coprococcus species in SSc, and increased abundance of Odoribacter, Bacteroides and Prevotella species in HC. KEGG pathway analysis demonstrated distinct differences between SSc versus HC, and between SSc (No-IS) and SSc (On-IS). CONCLUSIONS: Using metagenomic sequencing, our study further underlines distinct alterations in microbiota profiling among Asian SSc patients.


Assuntos
Microbioma Gastrointestinal , Esclerodermia Limitada , Escleroderma Sistêmico , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Microbioma Gastrointestinal/genética , Fezes , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/microbiologia , Bactérias/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-35185013

RESUMO

OBJECTIVE: Evidence indicates that multistrain probiotics benefit preterm infants more than single-strain (SS) probiotics. We assessed the effects of SS versus triple-strain (TS) probiotic supplementation (PS) in extremely preterm (EP) infants. DESIGN: EP infants (gestational age (GA) <28 weeks) were randomly allocated to TS or SS probiotic, assuring blinding. Reference (REF) group was EP infants in the placebo arm of our previous probiotic trial. PS was commenced with feeds and continued until 37 weeks' corrected GA. Primary outcome was time to full feed (TFF: 150 mL/kg/day). Secondary outcomes included short-chain fatty acids and faecal microbiota collected at T1 (first week) and T2 (after 3 weeks of PS) using 16S ribosomal RNA gene sequencing. RESULTS: 173 EP (SS: 86, TS: 87) neonates with similar GA and birth weight (BW) were randomised. Median TFF was comparable (11 (IQR 8-16) vs 10 (IQR 8-16) days, p=0.92). Faecal propionate (SS, p<0.001, and TS, p=0.0009) and butyrate levels (TS, p=0.029) were significantly raised in T2 versus T1 samples. Secondary clinical outcomes were comparable. At T2, alpha diversity was comparable (p>0.05) between groups, whereas beta-diversity analysis revealed significant differences between PS and REF groups (both p=0.001). Actinobacteria were higher (both p<0.01), and Proteobacteria, Firmicutes and Bacteroidetes were lower in PS versus REF. Gammaproteobacteria, Clostridia and Negativicutes were lower in both PS versus REF. CONCLUSION: TFF in EP infants was similar between SS and TS probiotics. Both probiotics were effective in reducing dysbiosis (higher bifidobacteria and lower Gammaproteobacteria). Long-term significance of increased propionate and butyrate needs further studies. TRIAL REGISTRATION NUMBER: ACTRN 12615000940572.


Assuntos
Lactente Extremamente Prematuro , Probióticos , Bifidobacterium , Butiratos , Firmicutes , Humanos , Lactente , Recém-Nascido , Probióticos/uso terapêutico , Propionatos
6.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35131944

RESUMO

The troposphere constitutes the final frontier of global ecosystem research due to technical challenges arising from its size, low biomass, and gaseous state. Using a vertical testing array comprising a meteorological tower and a research aircraft, we conducted synchronized measurements of meteorological parameters and airborne biomass (n = 480) in the vertical air column up to 3,500 m. The taxonomic analysis of metagenomic data revealed differing patterns of airborne microbial community composition with respect to time of day and height above ground. The temporal and spatial resolution of our study demonstrated that the diel cycle of airborne microorganisms is a ground-based phenomenon that is entirely absent at heights >1,000 m. In an integrated analysis combining meteorological and biological data, we demonstrate that atmospheric turbulence, identified by potential temperature and high-frequency three-component wind measurements, is the key driver of bioaerosol dynamics in the lower troposphere. Multivariate regression analysis shows that at least 50% of identified airborne microbial taxa (n = ∼10,000) are associated with either ground or height, allowing for an understanding of dispersal patterns of microbial taxa in the vertical air column. Due to the interconnectedness of atmospheric turbulence and temperature, the dynamics of microbial dispersal are likely to be impacted by rising global temperatures, thereby also affecting ecosystems on the planetary surface.


Assuntos
Microbiologia do Ar , Bactérias/classificação , Bactérias/isolamento & purificação , Aerossóis , Altitude , Atmosfera , Humanos
7.
EClinicalMedicine ; 39: 101076, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34430837

RESUMO

BACKGROUND: Shigellosis accounts for substantial morbidity and mortality worldwide and is the second most common cause of moderate and severe diarrhoea in children. METHODS: This phase 2b study (NCT03527173), conducted between August 2018 and November 2019, evaluated vaccine efficacy (VE), safety, and immunogenicity of a Shigella sonnei GMMA candidate vaccine (1790GAHB) in adults, using a S. sonnei 53 G controlled human infection model. Participants (randomized 1:1) received two doses of 1790GAHB or placebo (GAHB-Placebo), at day (D) 1 and D29, and an oral challenge of S. sonnei 53 G at D57. VE was evaluated using several endpoints, reflecting different case definitions of shigellosis. For the primary endpoint, the success criterion was a lower limit of the 90% confidence interval >0. FINDINGS: Thirty-six and 35 participants received 1790GAHB or placebo, respectively; 33 and 29 were challenged, 15 and 12 developed shigellosis. VE was not demonstrated for any endpoint. Adverse events were more frequent in 1790GAHB versus placebo recipients post-vaccination. Anti-S. sonnei lipopolysaccharide (LPS) IgG responses increased at D29 and remained stable through D57 in group 1790GAHB; no increase was shown in placebo recipients. INTERPRETATION: 1790GAHB had an acceptable safety profile and induced anti-LPS IgG responses but did not demonstrate clinical efficacy against shigellosis. Baseline/pre-challenge antibody levels were higher in participants who did not develop shigellosis post-challenge, suggesting a role of anti-LPS IgG antibodies in clinical protection, although not fully elucidated in this study. For further vaccine development an increased S. sonnei O-antigen content is likely needed to enhance anti-LPS immune responses. FUNDING: GlaxoSmithKline Biologicals SA, Bill and Melinda Gates Foundation.

8.
Front Neurol ; 12: 633777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790849

RESUMO

Alzheimer's disease (AD) and all other dementia represent a global challenge, with an estimated 50 million individuals in the world living with dementia today. In low and middle income countries (LMICs), the burden of disease often is greater, and some of these countries are projected to have some of the largest increases in dementia prevalence during the next few decades. As the world's largest voluntary health organization dedicated to AD and all other dementia, the Alzheimer's Association is committed to its vision of a world without dementia and recognizes the needs, challenges, and opportunities for dementia research in all parts of the world, and especially in LMICs. Currently, the Association is devoting more than $215 million in funding to nearly 600 best-of-field projects in 31 countries, including a significant number of projects that advance and support LMIC-specific research. The innovative work in LMICs is focused on addressing unmet needs or challenges associated with the many unique cultural, demographic, and economic characteristics of these countries. The Association also is expanding leading global forums such as the Alzheimer's Association International Conference (AAIC). In an effort to create new learning and participation opportunities, the Association also has been partnering with other international organizations and collaborating with local leadership to provide AAIC Satellite Symposia (AAIC SS) in LMIC regions around the world. In 2021 and beyond, the Association is committed to continuing these LMIC-focused initiatives, identifying gaps in LMIC research and resources, and enhancing collaboration and communication among researchers in these regions.

9.
Front Microbiol ; 11: 575377, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33250869

RESUMO

Metagenomics-based high-throughput sequencing (HTS) enables comprehensive detection of all species comprised in a sample with a single assay and is becoming a standard method for outbreak investigation. However, unlike real-time PCR or serological assays, HTS datasets generated for pathogen detection do not easily provide yes/no answers. Rather, results of the taxonomic read assignment need to be assessed by trained personnel to gain information thereof. Proficiency tests are important instruments of validation, harmonization, and standardization. Within the European Union funded project COMPARE [COllaborative Management Platform for detection and Analyses of (Re-) emerging and foodborne outbreaks in Europe], we conducted a proficiency test to scrutinize the ability to assess diagnostic metagenomics data. An artificial dataset resembling shotgun sequencing of RNA from a sample of contaminated trout was provided to 12 participants with the request to provide a table with per-read taxonomic assignments at species level and a report with a summary and assessment of their findings, considering different categories like pathogen, background, or contaminations. Analysis of the read assignment tables showed that the software used reliably classified the reads taxonomically overall. However, usage of incomplete reference databases or inappropriate data pre-processing caused difficulties. From the combination of the participants' reports with their read assignments, we conclude that, although most species were detected, a number of important taxa were not or not correctly categorized. This implies that knowledge of and awareness for potentially dangerous species and contaminations need to be improved, hence, capacity building for the interpretation of diagnostic metagenomics datasets is necessary.

10.
mSphere ; 5(5)2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968005

RESUMO

Controlled human infection models (CHIMs) are useful for vaccine development. To improve on existing models, we developed a CHIM using a lyophilized preparation of Shigella sonnei strain 53G produced using current good manufacturing practice (cGMP). Healthy adults were enrolled in an open-label dose-ranging study. Following administration of a dose of rehydrated S. sonnei strain 53G, subjects were monitored for development of disease. The first cohort received 500 CFU of 53G, and dosing of subsequent cohorts was based on results from the previous cohort. Subjects were administered ciprofloxacin on day 5 and discharged home on day 8. Subjects returned as outpatients for clinical checks and sample collection. Attack rates increased as the dose of S. sonnei was increased. Among those receiving the highest dose (1,760 CFU), 70% developed moderate to severe diarrhea, 50% had dysentery, and 40% had fever. Antilipopolysaccharide responses were observed across all cohorts. An S. sonnei CHIM using a lyophilized lot of strain 53G was established. A dose in the range of 1,500 to 2,000 CFU of 53G was selected as the dose for future challenge studies using this product. This model will enable direct comparison of study results between institutions and ensure better consistency over time in the challenge inoculum.IMPORTANCE Controlled human infection models (CHIMs) are invaluable tools utilized to understand the human response to infection, potentially leading to protective immune mechanisms and allowing efficacy testing of enteric countermeasures, including vaccines, antibiotics, and other products. The development of an improved Shigella CHIM for both Shigella sonnei and Shigella flexneri is consistent with international efforts, supported by international donors and the World Health Organization, focused on standardizing Shigella CHIMs and using them to accelerate Shigella vaccine development. The use of lyophilized Shigella challenge strains rather than plate-grown inoculum preparations is considered an important step forward in the standardization process. Furthermore, the results of studies such as this justify the development of lyophilized preparations for additional epidemiologically important S. flexneri serotypes, including S. flexneri 3a and S. flexneri 6.


Assuntos
Disenteria Bacilar/microbiologia , Shigella sonnei/imunologia , Adulto , Estudos de Coortes , Relação Dose-Resposta Imunológica , Feminino , Liofilização , Voluntários Saudáveis , Experimentação Humana/normas , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
mSphere ; 5(5)2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968012

RESUMO

Shigella is a major cause of moderate to severe diarrhea largely affecting children (<5 years old) living in low- and middle-income countries. Several vaccine candidates are in development, and controlled human infection models (CHIMs) can be useful tools to provide an early assessment of vaccine efficacy and potentially support licensure. A lyophilized strain of S. sonnei 53G was manufactured and evaluated to establish a dose that safely and reproducibly induced a ≥60% attack rate. Samples were collected pre- and postchallenge to assess intestinal inflammatory responses, antigen-specific serum and mucosal antibody responses, functional antibody responses, and memory B cell responses. Infection with S. sonnei 53G induced a robust intestinal inflammatory response as well as antigen-specific antibodies in serum and mucosal secretions and antigen-specific IgA- and IgG-secreting B cells positive for the α4ß7 gut-homing marker. There was no association between clinical disease outcomes and systemic or functional antibody responses postchallenge; however, higher lipopolysaccharide (LPS)-specific serum IgA- and IgA-secreting memory B cell responses were associated with a reduced risk of disease postchallenge. This study provides unique insights into the immune responses pre- and postinfection with S. sonnei 53G in a CHIM, which could help guide the rational design of future vaccines to induce protective immune responses more analogous to those triggered by infection.IMPORTANCE Correlate(s) of immunity have yet to be defined for shigellosis. As previous disease protects against subsequent infection in a serotype-specific manner, investigating immune response profiles pre- and postinfection provides an opportunity to identify immune markers potentially associated with the development of protective immunity and/or with a reduced risk of developing shigellosis postchallenge. This study is the first to report such an extensive characterization of the immune response after challenge with S. sonnei 53G. Results demonstrate an association of progression to shigellosis with robust intestinal inflammatory and mucosal gut-homing responses. An important finding in this study was the association of elevated Shigella LPS-specific serum IgA and memory B cell IgA responses at baseline with reduced risk of disease. The increased baseline IgA responses may contribute to the lack of dose response observed in the study and suggests that IgA responses should be further investigated as potential correlates of immunity.


Assuntos
Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Disenteria Bacilar/imunologia , Memória Imunológica , Adolescente , Adulto , Linfócitos B/imunologia , Vacinas Bacterianas/administração & dosagem , Fezes/química , Feminino , Liofilização , Humanos , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/análise , Imunoglobulina G/sangue , Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Mucosa/imunologia , Shigella sonnei/imunologia , Adulto Jovem
12.
Microbiol Resour Announc ; 8(37)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515336

RESUMO

Citricoccus sp. strain SGAir0253 was isolated from indoor air collected in Singapore. Its genome sequence was assembled using single-molecule real-time sequencing. It comprises one chromosome of 3.32 Mb and two plasmids of 137 kb and 99 kb. The genome consists of 2,950 protein-coding genes, 49 tRNAs, and 9 rRNAs.

13.
Foodborne Pathog Dis ; 16(7): 531-537, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31099590

RESUMO

A total of 73 nontyphoidal Salmonella enterica isolates, 33 from raw chicken meat and 40 from routine clinical specimens, were collected between 2015 and 2017 from eight cities in Sri Lanka for a pilot study of whole-genome sequencing for Salmonella surveillance. The isolates were characterized by conventional serotyping and whole-genome sequencing. The raw sequenced data were assembled and analyzed to predict Salmonella serotypes, determine sequence type (ST) profiles of genome and plasmid, and identify plasmid replicon sequences and antimicrobial resistance (AMR) genes. The most common serovar isolated from chicken meat was Salmonella enterica serovar Agona of ST13 (n = 16), in contrast to Salmonella enterica serovar Enteritidis of ST11 (n = 21) in human. Salmonella enterica serovar Corvallis is the only serovar that was overlapping between human and chicken meat. The level of agreement between serotyping and serotype prediction results was 100%. Among the 33 chicken isolates, multidrug resistance (MDR) was observed in five isolates, including two Salmonella enterica serovar Kentucky ST314, which harbored six different classes of AMR determinants. Among the 40 human isolates, MDR was detected in two Salmonella enterica serovar Chester (ST2063) isolates containing five different antibiotic classes of AMR determinants. Out of 73 isolates, the only human Salmonella enterica serovar Typhimurium strain of ST36 was found to possess extended-spectrum beta-lactamase (ESBL) gene, blaCTX-M-15, and it was positive for ESBL production. In summary, this study identified S. enterica serovars that were dominating in chicken meat and human and showed the genomic differences among the chicken meat and human strains. It should be noted that the limited number of isolates and sampling at a different time period means that thorough source attribution is not possible. To the best of our knowledge, this is the first report on the use of whole-genome sequencing analysis of nontyphoidal S. enterica isolated from chicken meat and human in Sri Lanka.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Produtos da Carne/microbiologia , Salmonella enterica/classificação , Salmonella enterica/isolamento & purificação , Animais , Galinhas , Humanos , Testes de Sensibilidade Microbiana , Projetos Piloto , Estudos Retrospectivos , Salmonella enterica/efeitos dos fármacos , Salmonella enteritidis/isolamento & purificação , Sorotipagem , Sri Lanka , Sequenciamento Completo do Genoma
14.
mSphere ; 3(3)2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29898979

RESUMO

Shigella is an important cause of diarrhea worldwide, with serotypes Shigella flexneri 2a, S. flexneri 3a, and Shigella sonnei demonstrating epidemiological prevalence. Many development efforts are focused on Shigella lipopolysaccharide (LPS)-based vaccines, as O antigen-specific conjugate vaccines are immunogenic and efficacious. Immunization with Shigella vaccines containing LPS can elicit antibodies capable of killing Shigella in a serotype-specific manner. Thus, to facilitate Shigella vaccine development, we have developed a serum bactericidal assay (SBA) specific for three Shigella serotypes that measures killing of target bacteria at multiple serum dilutions and in the presence of exogenous complement. The SBA has a high analytical throughput and uses simple technologies and readily available reagents. The SBA was characterized with human sera with bactericidal antibodies against S. flexneri 2a, S. flexneri 3a, and S. sonnei Purified LPS of a homologous serotype, but not a heterologous serotype, inhibited bacterial killing. Assessment of precision found median intra-assay precision to be 13.3% and median interassay precision to be 19 to 30% for the three serotypes. The SBA is linear, with slight deviations for samples with low (~40) killing indices. The SBA was sensitive enough to allow about 100-fold predilution of serum samples. Repeat assays yielded results with less than 2-fold deviations, indicating the robustness of the assay. Assay results from four different laboratories were highly comparable when normalized with a reference serum. The Shigella SBA, combined with a reference serum, should facilitate the development of Shigella vaccines across the field.IMPORTANCEShigella is an important cause of diarrhea worldwide, and efforts are ongoing to produce a safe and effective Shigella vaccine. Although a clear immune correlate of protection has not been established, antibodies with bactericidal capacity may provide one means of protecting against shigellosis. Thus, it is important to measure the functional capacity of antibodies, as opposed to only binding activity. This article describes a simple, robust, and high-throughput serum bactericidal assay capable of measuring Shigella-specific functional antibodies in vitro We show for the first time that this assay was successfully performed by multiple laboratories and generated highly comparable results, particularly when SBA titers were normalized using a reference standard. The serum bactericidal assay, along with a reference serum, should greatly facilitate Shigella vaccine development.


Assuntos
Anticorpos Antibacterianos/sangue , Atividade Bactericida do Sangue , Disenteria Bacilar/imunologia , Ensaios de Triagem em Larga Escala/métodos , Imunoensaio/métodos , Shigella flexneri/imunologia , Shigella sonnei/imunologia , Antígenos de Bactérias/imunologia , Humanos , Lipopolissacarídeos/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soro/imunologia , Shigella flexneri/fisiologia , Shigella sonnei/fisiologia
15.
Sex Transm Infect ; 93(3): 226-228, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27582249

RESUMO

OBJECTIVES: Local authorities (LAs) in England commission chlamydia screening as part of the National Chlamydia Screening Programme. It is recommended that LAs achieve a chlamydia diagnosis rate of ≥2300 cases per 100 000 population aged 15-24. We describe national patterns in attainment of the chlamydia diagnosis rate recommendation and possible implications of using it to measure LA-level performance. METHODS: We used publicly available data sets from England (2012) to explore the association between LAs attaining the recommended chlamydia diagnosis rate and population size, socioeconomic deprivation, test setting and sex. RESULTS: We used data from 1 197 121 recorded chlamydia tests in females and 564 117 in males. The chlamydia diagnosis rate recommendation was achieved by 22% (72/324) of LAs overall (43% female population; 8% male population). LAs in the highest deprivation quintile were more likely to reach the recommendation than those in the least-deprived quintile for both sexes (women: unadjusted prevalence ratio (UPR) 7.43, 95% CI 3.65 to 15.11; men: UPR 7.00, 95% CI 1.66 to 29.58). The proportion of tests performed in genitourinary medicine clinics was negatively associated with attainment of the recommended diagnosis rate (UPR 0.95, 0.93 to 0.97). CONCLUSIONS: Chlamydia diagnosis rate recommendations that reflect local area deprivation (as a proxy for disease burden) may be more appropriate than a single national target if the aim is to reduce health inequalities nationally. We suggest LAs monitor their chlamydia diagnosis rate, test coverage and test positivity across a range of measures (including setting and sex) and pre/post changes to commissioned services. Critical evaluation of performance against the recommendation should be reflected in local commissioning decisions.


Assuntos
Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Adolescente , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/isolamento & purificação , Inglaterra/epidemiologia , Feminino , Disparidades em Assistência à Saúde , Humanos , Masculino , Programas de Rastreamento , Densidade Demográfica , Prevalência , Classe Social , Adulto Jovem
16.
Vaccine ; 33(46): 6156-60, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26428454

RESUMO

Live, whole cell killed and subunit vaccines are being developed for diarrheal diseases caused by V. cholerae, Shigella species, ETEC, and Campylobacter. Some of these vaccines can be administered orally since this route best mimics natural infection. Live vaccines administered orally have to be protected from the harsh acidic gastric environment. Milk and bicarbonate solutions have been administered to neutralize the stomach acid. For many Shigella vaccine trials, 100-120 ml of a bicarbonate solution is ingested followed by the live vaccine candidate, which is delivered in 30 ml of bicarbonate, water or saline. It is not clear if maximum bacterial viability is achieved under these conditions. Also, volumes of neutralizing buffer that are optimal for adults may be unsuitable for children and infants. To address these questions, we performed studies to determine the viability and stability of a Shigella sonnei vaccine candidate, WRSS1, in a mixture of different volumes of five different buffer solutions added to hydrochloric acid to simulate gastric acidity. Among the buffers tested, bicarbonate solution, rotavirus buffer and CeraVacx were better at neutralizing acid and maintaining the viability of WRSS1. Also, a much smaller volume of the neutralizing buffer was sufficient to counteract stomach acid while maintaining bacterial viability.


Assuntos
Soluções Tampão , Viabilidade Microbiana/efeitos dos fármacos , Vacinas contra Shigella/química , Vacinas contra Shigella/imunologia , Shigella sonnei/efeitos dos fármacos , Shigella sonnei/imunologia , Administração Oral , Estabilidade de Medicamentos , Humanos , Ácido Clorídrico/toxicidade , Vacinas contra Shigella/administração & dosagem
17.
Oncotarget ; 5(12): 3983-95, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24980818

RESUMO

Tumor survival is influenced by interactions between tumor cells and the stromal microenvironment. One example is Endosialin (Tumor Endothelial Marker-1 (TEM-1) or CD248), which is expressed primarily by cells of mesenchymal origin and some tumor cells. The expression, as a function of architectural masking, of TEM-1 and its pathway-associated proteins was quantified and examined for association with five-year disease-specific survival on a colorectal cancer (CRC) cohort divided into training (n=330) and validation (n=164) sets. Although stromal expression of TEM-1 had prognostic value, a more significant prognostic signature was obtained through linear combination of five compartment-specific expression scores (TEM-1 Stroma, TEM-1 Tumor Vessel, HIF2α Stromal Vessel, Collagen IV Tumor, and Fibronectin Stroma). This resulted in a single continuous risk score (TAPPS: TEM-1 Associated Pathway Prognostic Signature) which was significantly associated with decreased survival on both the training set [HR=1.76 (95%CI: 1.44-2.15); p<0.001] and validation set [HR=1.38 (95%CI: 1.02-1.88); p=0.04]. Importantly, since prognosis is a critical clinical question in Stage II patients, the TAPPS score also significantly predicted survival in the Stage II patient (n=126) cohort [HR=1.75 (95%CI: 1.22-2.52); p=0.002] suggesting the potential of using the TAPPS score to assess overall risk in CRC patients, and specifically in Stage II patients.


Assuntos
Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Neoplasias Colorretais/patologia , Estudos de Coortes , Neoplasias Colorretais/mortalidade , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Proteínas de Neoplasias , Prognóstico , Análise de Sobrevida , Microambiente Tumoral
18.
Front Neural Circuits ; 7: 194, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24376399

RESUMO

A central problem in cortical processing including sensory binding and attentional gating is how neurons can synchronize their responses with zero or near-zero time lag. For a spontaneously firing neuron, an input from another neuron can delay or advance the next spike by different amounts depending upon the timing of the input relative to the previous spike. This information constitutes the phase response curve (PRC). We present a simple graphical method for determining the effect of PRC shape on synchronization tendencies and illustrate it using type 1 PRCs, which consist entirely of advances (delays) in response to excitation (inhibition). We obtained the following generic solutions for type 1 PRCs, which include the pulse-coupled leaky integrate and fire model. For pairs with mutual excitation, exact synchrony can be stable for strong coupling because of the stabilizing effect of the causal limit region of the PRC in which an input triggers a spike immediately upon arrival. However, synchrony is unstable for short delays, because delayed inputs arrive during a refractory period and cannot trigger an immediate spike. Right skew destabilizes antiphase and enables modes with time lags that grow as the conduction delay is increased. Therefore, right skew favors near synchrony at short conduction delays and a gradual transition between synchrony and antiphase for pairs coupled by mutual excitation. For pairs with mutual inhibition, zero time lag synchrony is stable for conduction delays ranging from zero to a substantial fraction of the period for pairs. However, for right skew there is a preferred antiphase mode at short delays. In contrast to mutual excitation, left skew destabilizes antiphase for mutual inhibition so that synchrony dominates at short delays as well. These pairwise synchronization tendencies constrain the synchronization properties of neurons embedded in larger networks.


Assuntos
Potenciais de Ação/fisiologia , Condução Nervosa/fisiologia , Inibição Neural/fisiologia , Neurônios/fisiologia , Animais , Simulação por Computador , Modelos Neurológicos , Rede Nervosa/fisiologia
19.
Biomark Med ; 7(6): 933-46, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24266829

RESUMO

AIM: Although agents that target FRA have advanced through clinical trials, comprehensive analyses of FRA expression in epithelial cancers compared with clinical variables and prognosis are limited. MATERIALS & METHODS: FRA expression was examined in non-small-cell lung cancer (NSCLC), ovarian cancer and endometrial cancer cohorts using AQUA(®) technology. RESULTS: For the NSCLC cohort, FRA expression was significantly higher in adenocarcinoma samples (p < 0.001) than other histologies, and in females (p = 0.003) versus males. High FRA expression was significantly associated with better survival in NSCLC cases (p = 0.01) while significantly and independently associated with worse prognosis in endometrial (p < 0.001) and ovarian cancers (p < 0.001). CONCLUSION: These studies confirm the prognostic value of FRA in multiple indications. The opposing prognostic effects observed may suggest differential biology.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Receptor 1 de Folato/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , Neoplasias Ovarianas/diagnóstico , Adulto , Idoso , Anticorpos Monoclonais/imunologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Estudos de Coortes , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/patologia , Feminino , Receptor 1 de Folato/imunologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Modelos de Riscos Proporcionais
20.
Artigo em Inglês | MEDLINE | ID: mdl-23518906

RESUMO

We used optical imaging with voltage-sensitive dyes to investigate the spatio-temporal dynamics of synaptically evoked activity in brain slices of the inferior colliculus (IC). Responses in transverse slices which preserve cross-frequency connections and in modified sagittal slices that preserve connections within frequency laminae were evoked by activating the lateral lemniscal tract. Comparing activity between small and large populations of cells revealed response areas in the central nucleus of the IC that were similar in magnitude but graded temporally. In transverse sections, these response areas are summed to generate a topographic response profile. Activity through the commissure to the contralateral IC required an excitation threshold that was reached when GABAergic inhibition was blocked. Within laminae, module interaction created temporal homeostasis. Diffuse activity evoked by a single lemniscal shock re-organized into distinct spatial and temporal compartments when stimulus trains were used, and generated a directional activity profile within the lamina. Using different stimulus patterns to activate subsets of microcircuits in the central nucleus of the IC, we found that localized responses evoked by low-frequency stimulus trains spread extensively when train frequency was increased, suggesting recruitment of silent microcircuits. Long stimulus trains activated a circuit specific to post-inhibitory rebound neurons. Rebound microcircuits were defined by a focal point of initiation that spread to an annular ring that oscillated between inhibition and excitation. We propose that much of the computing power of the IC is derived from local circuits, some of which are cell-type specific. These circuits organize activity within and across frequency laminae, and are critical in determining the stimulus-selectivity of auditory coding.


Assuntos
Corantes Fluorescentes/análise , Colículos Inferiores/química , Colículos Inferiores/citologia , Rede Nervosa/química , Rede Nervosa/citologia , Imagens com Corantes Sensíveis à Voltagem/métodos , Estimulação Acústica/métodos , Animais , Vias Auditivas/química , Vias Auditivas/citologia , Vias Auditivas/fisiologia , Colículos Inferiores/fisiologia , Camundongos , Camundongos Endogâmicos CBA , Rede Nervosa/fisiologia , Ratos , Ratos Long-Evans
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