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1.
Vaccine ; 41(42): 6227-6238, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673715

RESUMO

BACKGROUND: The Global COVID Vaccine Safety (GCoVS) project was established in 2021 under the multinational Global Vaccine Data Network (GVDN) consortium to facilitate the rapid assessment of the safety of newly introduced vaccines. This study analyzed data from GVDN member sites on the background incidence rates of conditions designated as adverse events of special interest (AESI) for COVID-19 vaccine safety monitoring. METHODS: Eleven GVDN global sites obtained data from national or regional healthcare databases using standardized methods. Incident events of 13 pre-defined AESI were included for a pre-pandemic period (2015-19) and the first pandemic year (2020). Background incidence rates (IR) and 95% confidence intervals (CI) were calculated for inpatient and emergency department encounters, stratified by age and sex, and compared between pre-pandemic and pandemic periods using incidence rate ratios. RESULTS: An estimated 197 million people contributed 1,189,652,926 person-years of follow-up time. Among inpatients in the pre-pandemic period (2015-19), generalized seizures were the most common neurological AESI (IR ranged from 22.15 [95% CI 19.01-25.65] to 278.82 [278.20-279.44] per 100,000 person-years); acute disseminated encephalomyelitis was the least common (<0.5 per 100,000 person-years at most sites). Pulmonary embolism was the most common thrombotic event (IR 45.34 [95% CI 44.85-45.84] to 93.77 [95% CI 93.46-94.08] per 100,000 person-years). The IR of myocarditis ranged from 1.60 [(95% CI 1.45-1.76) to 7.76 (95% CI 7.46-8.08) per 100,000 person-years. The IR of several AESI varied by site, healthcare setting, age and sex. The IR of some AESI were notably different in 2020 compared to 2015-19. CONCLUSION: Background incidence of AESIs exhibited some variability across study sites and between pre-pandemic and pandemic periods. These findings will contribute to global vaccine safety surveillance and research.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Incidência , Vacinação , Vacinas/efeitos adversos
2.
Vaccine ; 39(45): 6671-6681, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34635375

RESUMO

BACKGROUND: Universal mass vaccination (UMV) against rotavirus has been implemented in many but not all European countries. This study investigated the impact of UMV on rotavirus incidence trends by comparing European countries with UMV: Belgium, England/Wales and Germany versus countries without UMV: Denmark and the Netherlands. METHODS: For this observational retrospective cohort study, time series data (2001-2016) on rotavirus detections, meteorological factors and population demographics were collected. For each country, several meteorological and population factors were investigated as possible predictors of rotavirus incidence. The final set of predictors were incorporated in negative binomial models accounting for seasonality and serial autocorrelation, and time-varying incidence rate ratios (IRR) were calculated for each age group and country separately. The overall vaccination impact two years after vaccine implementation was estimated by pooling the results using a random effects meta-analyses. Independent t-tests were used to compare annual epidemics in the pre-vaccination and post-vaccination era to explore any changes in the timing of rotavirus epidemics. RESULTS: The population size and several meteorological factors were predictors for the rotavirus epidemiology. Overall, we estimated a 42% (95%-CI 23;56%) reduction in rotavirus incidence attributable to UMV. Strongest reductions were observed for age-groups 0-, 1- and 2-years (IRR 0.47, 0.48 and 0.63, respectively). No herd effect induced by UMV in neighbouring countries was observed. In all UMV countries, the start and/or stop and corresponding peak of the rotavirus season was delayed by 4-7 weeks. CONCLUSIONS: The introduction of rotavirus UMV resulted in an overall reduction of 42% in rotavirus incidence in Western European countries two years after vaccine introduction and caused a change in seasonal pattern. No herd effect induced by UMV neighbouring countries was observed for Denmark and the Netherlands.


Assuntos
Gastroenterite , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Europa (Continente)/epidemiologia , Hospitalização , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinação
3.
J Hosp Infect ; 117: 44-51, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34302884

RESUMO

BACKGROUND: Microbiological monitoring may be indicated by the local risk assessment of hospital water systems. When water sampling is carried out, it is imperative that the activity of any residual biocide is completely neutralized. Sodium thiosulphate pentahydrate (Na2S2O3·5H2O) is commonly used to neutralize oxidizing biocides in water samples for microbiological testing. Ethylenediaminetetraacetic acid dihydrate (Na2EDTA.2H2O) is recommended to neutralize silver-copper ionization treated water samples. However, there are inconsistencies in the recommended effective concentration. Furthermore, sampling bottles dosed with Na2EDTA.2H2O are not commercially available. AIM: To investigate the efficacy of Na2EDTA.2H2O as a neutralizing agent compared with sodium thiosulphate (Na2S2O3·5H2O) on water samples treated with silver and copper ions and to assess the biocidal activity in water samples. METHODS: An interlaboratory investigation was carried out using simulated water samples spiked with Legionella pneumophila or Pseudomonas aeruginosa with and without silver and copper ions. Bacterial recovery was determined in sterile sampling bottles dosed with either 50 mg/L Na2EDTA.2H2O or 180 mg/L Na2S2O3·5H2O as the chemical biocide neutralizing agent. FINDINGS: Na2S2O3·5H2O effectively complexed both silver and copper ions and inhibited biocidal activity. The 50 mg/L of Na2EDTA.2H2O continued to demonstrate significant biocidal activity in the spiked samples. CONCLUSION: This study demonstrated that Na2EDTA.2H2O is not an efficacious neutralizing agent on water samples treated with silver and copper ions. Sample bottles dosed with 180 mg/L Na2S2O3·5H2O were more effective in neutralizing silver and copper ions generated in water that had been treated by silver-copper ionization systems.


Assuntos
Legionella pneumophila , Legionella , Cobre/farmacologia , Desinfecção , Humanos , Pseudomonas , Água , Microbiologia da Água , Abastecimento de Água
4.
Sleep Med ; 84: 20-25, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34090009

RESUMO

INTRODUCTION: Obstructive sleep apnea (OSA) is a highly prevalent disorder associated with increased cardiovascular risks. We explored the predictive value of OSA screening instruments in cardiac disease patients awaiting cardiac surgery. METHODS: In this prospective cohort, 107 participants awaiting cardiac surgery from Cleveland Clinic and Johns Hopkins underwent polysomnography after completing Epworth Sleepiness Scale (ESS), Sleep Apnea/Sleep Disorder Questionnaire (SA/SDQ), STOP, STOPBAG2 and Berlin questionnaires. Score comparisons between groups based on apnea-hypopnea index (AHI) ≥15 were performed. Logistic regression with receiver operating characteristic (ROC) analysis was used to investigate optimal threshold. RESULTS: Prevalence of OSA (AHI ≥5) was 71.9% (77/107) and 51 (47.7%) had moderate-to-severe disease (AHI ≥15). Participants were primarily male (57%) and Caucasian (76.6%). Mean age was 67.3 ± 13.3 years and BMI was 26.5 ± 6.6. Of the five screening tools, STOPBAG2 with a cut-point of 0.381 provided 78% sensitivity and 38% specificity (AUC 0.66, 95%CI 0.55-0.77). SA/SDQ yielded a cut-point of 32 for all subjects (AUC: 0.62, 95%CI 0.51-0.73) with sensitivity and specificity of 60% and 62% respectively, while STOP score ≥2 provided sensitivity and specificity of 67% and 52% respectively (AUC: 0.61, 95%CI 0.51-0.72). Among STOP items, "observed apnea" had the strongest correlation with AHI ≥15 (OR 3.67, 95%CI 1.57-8.54, p = 0.003). The ESS and Berlin were not useful in identifying moderate-to-severe OSA. CONCLUSION: Common screening tools had suboptimal performance in cardiac surgery patients. STOPBAG2 was better at predicting the probability of moderate-to-severe OSA in patients undergoing cardiac surgery compared to ESS, SA/SDQ, STOP and Berlin questionnaires.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Apneia Obstrutiva do Sono , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Estudos Prospectivos , Sensibilidade e Especificidade , Apneia Obstrutiva do Sono/diagnóstico , Inquéritos e Questionários
5.
Clin Exp Immunol ; 204(1): 125-133, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33314126

RESUMO

The United Kingdom has a national immunization programme which includes annual influenza vaccination in school-aged children, using live attenuated influenza vaccine (LAIV). LAIV is given annually, and it is unclear whether repeat administration can affect immunogenicity. Because LAIV is delivered intranasally, pre-existing local antibody might be important. In this study, we analysed banked samples from a study performed during the 2017/18 influenza season to investigate the role of pre-existing influenza-specific nasal immunoglobulin (Ig)A in children aged 6-14 years. Nasopharyngeal swabs were collected prior to LAIV immunization to measure pre-existing IgA levels and test for concurrent upper respiratory tract viral infections (URTI). Oral fluid samples were taken at baseline and 21-28 days after LAIV to measure IgG as a surrogate of immunogenicity. Antibody levels at baseline were compared with a pre-existing data set of LAIV shedding from the same individuals, measured by reverse transcription-polymerase chain reaction. There was detectable nasal IgA specific to all four strains in the vaccine at baseline. However, baseline nasal IgA did not correlate with the fold change in IgG response to the vaccine. Baseline nasal IgA also did not have an impact upon whether vaccine virus RNA was detectable after immunization. There was no difference in fold change of antibody between individuals with and without an URTI at the time of immunization. Overall, we observed no effect of pre-existing influenza-specific nasal antibody levels on immunogenicity, supporting annual immunization with LAIV in children.


Assuntos
Anticorpos Antivirais/imunologia , Imunogenicidade da Vacina/imunologia , Imunoglobulina A/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Cavidade Nasal/imunologia , Administração Intranasal , Adolescente , Criança , Feminino , Humanos , Imunoglobulina G/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Masculino , Cavidade Nasal/virologia , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Eliminação de Partículas Virais/imunologia
6.
Support Care Cancer ; 29(6): 3183-3189, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33089370

RESUMO

OBJECTIVE: To establish the intrarater reliability of lower limb circumference measures in a sample of individuals who are diagnosed with lower limb lymphoedema and to evaluate if change in limb position has an effect on the reliability of circumferential measures. METHOD: A sample of forty-one adults diagnosed with a lower limb lymphoedema were recruited. Participants had their affected leg measured three times by a qualified therapist during a standard outpatient appointment: twice in a lying position and once in sitting with knee flexed at 90°. To examine the intrarater reliability, interclass correlation coefficients (ICC) with 95% confident intervals were calculated. RESULTS: Excellent intrarater reliability was established at each measurement point and for the sum of circumferential measures when the limb remeasured in the same position by the same therapist. Changing the position of the limb resulted in lower intrarater reliability values at 10 and 30 cm from the base of the foot. CONCLUSIONS: The current study provides evidence for the intrarater reliability of lower limb circumference measures and highlights the need for consistency when remeasuring and monitoring the limb of those diagnosed with lower limb lymphoedema. IMPLICATIONS FOR CANCER SURVIVORS: Lymphoedema is a significant problem for breast cancer survivors but also provides lifetime risk to all survivors of lymph node surgery for solid tumours. The monitoring and surveillance of leg circumference measures of people diagnosed with lower limb lymphoedema has been a valuable instrument when reviewing progress of this chronic condition.


Assuntos
Perna (Membro)/fisiopatologia , Linfedema/diagnóstico , Amplitude de Movimento Articular/fisiologia , Idoso , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
7.
Vaccine ; 38(32): 4935-4939, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32536544

RESUMO

Kawasaki disease (KD) is an uncommon condition occasionally reported after childhood vaccination. Admissions with a KD-compatible diagnosis identified from a national database in England were linked to immunisation records to investigate the risk after pneumococcal conjugate (PCV) or meningococcal B (MenB) vaccines. Both are given at 2/4/12 months of age but were introduced sequentially, allowing their effects to be separately assessed. A total of 553 linked admissions in 512 individuals were validated as KD. The relative incidence (RI) within 28 days of PCV doses 1 or 2 measured by the self-controlled case-series method was 0.62 (95% confidence interval (CI) 0.38-1.00) with a significantly decreased risk after dose 3 (RI 0.30 (95% CI 0.11-0.77)). For MenB vaccine, the RI after doses 1 or 2 was 1.03 (95% CI 0.51-2.05) and 0.64 (95% CI 0.08-5.26) after dose 3. This study shows no evidence of an increased risk of KD after either vaccine.


Assuntos
Vacinas Meningocócicas , Síndrome de Linfonodos Mucocutâneos , Infecções Pneumocócicas , Criança , Inglaterra/epidemiologia , Humanos , Esquemas de Imunização , Lactente , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Vacinas Conjugadas
8.
Artigo em Espanhol | LILACS | ID: biblio-1396247

RESUMO

La miastenia gravis es una enfermedad neuromuscular crónica debida a deficiencia de transmisión nerviosa en la unión neuromuscular, de origen generalmente autoinmune en el adulto, que se caracteriza por grados variables de debilidad de los músculos esqueléticos del cuerpo, que aumenta durante los períodos de actividad y disminuye después de períodos de descanso. Sin embargo en la infancia cobran especial relevancia los síndromes miasténicos congénitos, que encuentran su origen en mutaciones de genes que codifican proteínas que juegan papeles clave en el mantenimiento de la transmisión neuromuscular, teniendo edad de inicio, distribución de debilidad y respuesta a tratamiento variables. Se presentan tres casos con el objetivo de describir el comportamiento clínico de la enfermedad y la utilidad de estudios complementarios ya que es de suma importancia su precoz identificación y tratamiento. Palabras claves: Miastenia gravis, test de estimulación repetitiva, ptosis palpebral, unión neuromuscular, pares craneanos


Myasthenia gravis is a chronic neuromuscular disease due to deficiency of nerve transmission in the neuromuscular junction, usually of an autoimmune origin in the adult, which is characterized by varying degrees of weakness of the skeletal muscles of the body, which increases during periods of activity and decreases after periods of rest. In childhood, however, congenital myasthenic syndromes, which find their origin in mutations of genes that encode proteins that play key roles in maintaining neuromuscular transmission, which may have a varying age of onset, distribution of weakness and response to treatment, are particularly relevant. Three cases are presented with the aim of describing the clinical presentation and course of the disease and the usefulness of complementary studies, since its early diagnosis and treatment is of paramount importance.Keywords: Myasthenia gravis, repetitive stimulation test, palpebral ptosis, neuromuscular junction, cranial pairs.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Miastenia Gravis/diagnóstico , Blefaroptose , Nervos Cranianos , Estimulação Elétrica/métodos , Junção Neuromuscular
9.
Epidemiol Infect ; 148: e60, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32079547

RESUMO

For outbreaks of gastrointestinal disease, rapid identification of the source is crucial to enable public health intervention and prevent further cases. Outbreak investigation comprises analyses of exposure information from cases and, if required, undertaking analytical epidemiological studies. Hypothesis generation has been reliant on empirical knowledge of exposures historically associated with a given pathogen. Epidemiology studies are resource-intensive and prone to bias, one of the reasons being the difficulties in recruiting appropriate controls. For this paper, the information from cases was compared against pre-defined background exposure information. As exemplars, three past outbreaks were used, one of common and two of rare exposures. Information from historical case trawling questionnaires was used to define background exposure having removed any exposures implicated with the outbreak. The case-background approach showed good sensitivity and specificity, identifying correctly all outbreak-related exposures. One additional exposure related to a retailer was identified and four food items where all cases had been exposed. In conclusion, the case-background method, a development of the case-case design, can be used to assist with hypothesis generation or when a case-control study may not be possible to carry out.


Assuntos
Surtos de Doenças , Exposição Ambiental/estatística & dados numéricos , Projetos de Pesquisa Epidemiológica , Gastroenteropatias/epidemiologia , Adulto , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Pública , Estudos Retrospectivos , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/transmissão , Adulto Jovem
10.
Vaccine ; 38(15): 3149-3156, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-31980192

RESUMO

Schools are increasingly being used to deliver vaccines. In 2015/16 three school-based vaccination programmes were delivered to adolescents in England: human papillomavirus (HPV), meningococcal groups A, C, W and Y disease (MenACWY) and tetanus, diphtheria and polio (Td/IPV). We assessed how school delivery models impact vaccine coverage and how a delivery model for one programme may impact another. Routinely collected national data were analysed to ascertain the school grade achieving highest coverage within each one-dose programme and to compare two-dose delivery models (within year vs across years) for the HPV vaccine. We also assessed whether the HPV delivery model was associated with coverage in other programmes. MenACWY and Td/IPV coverage was highest in younger school grades. Overall similar HPV coverage was achieved with both models (86.7% two doses within one year, 85.8% two doses across two years, p = 0.20). High two-dose HPV coverage in 2015/16 was reported in areas that achieved high HPV coverage in 2013/14 when three doses were required. Areas with high three-dose coverage in 2013/14 achieved higher coverage with a within-one-year approach (92.0% vs 85.2%, p < 0.001), whilst areas reporting low coverage in 2013/14 achieved lower but similar coverage in 2015/16 with both models (79.2% vs 80.9% p = 0.29). MenACWY and Td/IPV coverage were higher in areas with high HPV coverage in 2013/14. Among high HPV coverage areas, MenACWY coverage was higher when HPV doses were delivered within year. School-based programmes should be offered as early as feasible and acceptable to optimise coverage. The choice of delivery model for HPV should take into account local performance and provider experience. Single providers may delivery multiple vaccines and the delivery for one programme may affect the performance of other programmes. Providers should consider local circumstances including past and current vaccine coverage and factors influencing coverage when deciding what delivery model to adopt.


Assuntos
Programas de Imunização/organização & administração , Vacinas contra Papillomavirus/administração & dosagem , Serviços de Saúde Escolar/organização & administração , Adolescente , Criança , Inglaterra , Humanos , Papillomaviridae
11.
Clin Exp Immunol ; 199(2): 109-118, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31670841

RESUMO

Different vaccine strains included in the live attenuated influenza vaccine (LAIV) have variable efficacy. The reasons for this are not clear and may include differences in immunogenicity. We report a Phase IV open-label study on the immunogenicity of a single dose of quadrivalent LAIV (Fluenz™ Tetra) in children during the 2015/16 season, to investigate the antibody responses to different strains. Eligible children were enrolled to receive LAIV; nasal samples were collected before and approximately 4 weeks after immunization. There was a significant increase in nasal immunoglobulin (Ig)A to the H3N2, B/Victoria lineage (B/Brisbane) and B/Yamagata lineage (B/Phuket) components, but not to the H1N1 component. The fold change in nasal IgA response was inversely proportional to the baseline nasal IgA titre for H1N1, H3N2 and B/Brisbane. We investigated possible associations that may explain baseline nasal IgA, including age and prior vaccination status, but found different patterns for different antigens, suggesting that the response is multi-factorial. Overall, we observed differences in immune responses to different viral strains included in the vaccine; the reasons for this require further investigation.


Assuntos
Anticorpos Antivirais/imunologia , Imunização , Imunoglobulina A/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/administração & dosagem , Cavidade Nasal/imunologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Vacinas Vivas não Atenuadas/administração & dosagem
12.
Vaccine ; 38(2): 158-164, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31648914

RESUMO

2013/14 saw the start of the introduction of a new live attenuated influenza vaccine (LAIV) programme for children in England. 2018/19 saw co-circulation of both A(H1N1)pdm09 and A(H3N2), when LAIV was offered to all healthy children 2-9 years of age. LAIV effectiveness against influenza hospitalisation is not well described. This paper presents the 2018/19 end-of-season adjusted vaccine effectiveness (aVE) against laboratory confirmed influenza related hospitalisation in children aged 2-17. The test negative case control approach was used to estimate aVE by influenza A subtype and vaccine type. Cases and controls were selected from a sentinel laboratory surveillance system which collates details of individuals tested for influenza with reverse-transcription polymerase chain reaction (RT-PCR) on respiratory samples. Vaccine and clinical history was obtained from general practitioners of study participants. There were 307 hospitalised cases and 679 hospitalised controls. End-of-season influenza aVE was 53.0% (95% CI: 33.3, 66.8) against influenza confirmed hospitalisation; 63.5% (95% CI: 34.4, 79.7) against influenza A(H1N1)pdm09 hospitalisation and 31.1% (95% CI: -53.9, 69.2) against influenza A(H3N2). LAIV aVE was 49.1% (95% CI: 25.9, 65.0) for any influenza and 70.7% (95% CI: 41.8, 85.3) for A(H1N1)pdm09, whereas for those receiving quadrivalent inactivated influenza vaccine (QIV), aVE was 64.4% (95% CI: 29.4, 82.0) and 44.4% (95% CI: -51.9, 79.6) respectively. We provide evidence of overall significant VE for both LAIV and QIV against influenza associated hospitalisation in children 2-17 years of age, most notably against influenza A(H1N1)pdm09, with non-significant protection against A(H3N2).


Assuntos
Hospitalização/estatística & dados numéricos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Vigilância de Evento Sentinela , Vacinação , Vacinas Atenuadas/administração & dosagem
13.
Free Radic Biol Med ; 143: 341-353, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31446054

RESUMO

Leishmania amazonensis is one of leishmaniasis' causative agents, a disease that has no cure and leads to the appearance of cutaneous lesions. Recently, our group showed that heme activates a Na+/K+ ATPase in these parasites through a signaling cascade involving hydrogen peroxide (H2O2) generation. Heme has a pro-oxidant activity and signaling capacity, but the mechanism by which this molecule increases H2O2 levels in L. amazonensis has not been elucidated. Here we investigated the source of H2O2 stimulated by heme, ruling out the participation of mitochondria and raising the possibility of a role for a NADPH oxidase (Nox) activity. Despite the absence of a classical Nox sequence in trypanosomatid genomes, L. amazonensis expresses a surface ferric iron reductase (LFR1). Interestingly, Nox enzymes are thought to have evolved from ferric iron reductases because they share same core domain and are very similar in structure. The main difference is that Nox catalyses electron flow from NADPH to oxygen, generating reactive oxygen species (ROS), while ferric iron reductase promotes electron flow to ferric iron, generating ferrous iron. Using L. amazonensis overexpressing or knockout for LFR1 and heterologous expression of LFR1 in mammalian embryonic kidney (HEK 293) cells, we show that this enzyme is bifunctional, being able to generate both ferrous iron and H2O2. It was previously described that protozoans knockout for LFR1 have their differentiation to virulent forms (amastigote and metacyclic promastigote) impaired. In this work, we observed that LFR1 overexpression stimulates protozoan differentiation to amastigote forms, reinforcing the importance of this enzyme in L. amazonensis life cycle regulation. Thus, we not only identified a new source of ROS production in Leishmania, but also described, for the first time, an enzyme with both ferric iron reductase and Nox activities.


Assuntos
FMN Redutase/metabolismo , Peróxido de Hidrogênio/metabolismo , Ferro/metabolismo , Leishmania/enzimologia , Leishmaniose/parasitologia , NADPH Oxidases/metabolismo , Proteínas de Protozoários/metabolismo , Células HEK293 , Heme/metabolismo , Humanos , Leishmania/crescimento & desenvolvimento , Leishmaniose/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/parasitologia , NADPH Oxidases/genética , Oxirredução , Proteínas de Protozoários/genética
14.
Epidemiol Infect ; 147: e201, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364557

RESUMO

England has recently started a new paediatric influenza vaccine programme using a live-attenuated influenza vaccine (LAIV). There is uncertainty over how well the vaccine protects against more severe end-points. A test-negative case-control study was used to estimate vaccine effectiveness (VE) in vaccine-eligible children aged 2-16 years of age in preventing laboratory-confirmed influenza hospitalisation in England in the 2015-2016 season using a national sentinel laboratory surveillance system. Logistic regression was used to estimate the VE with adjustment for sex, risk-group, age group, region, ethnicity, deprivation and month of sample collection. A total of 977 individuals were included in the study (348 cases and 629 controls). The overall adjusted VE for all study ages and vaccine types was 33.4% (95% confidence interval (CI) 2.3-54.6) after adjusting for age group, sex, index of multiple deprivation, ethnicity, region, sample month and risk group. Risk group was shown to be an important confounder. The adjusted VE for all influenza types for the live-attenuated vaccine was 41.9% (95% CI 7.3-63.6) and 28.8% (95% CI -31.1 to 61.3) for the inactivated vaccine. The study provides evidence of the effectiveness of influenza vaccination in preventing hospitalisation due to laboratory-confirmed influenza in children in 2015-2016 and continues to support the rollout of the LAIV childhood programme.


Assuntos
Hospitalização/estatística & dados numéricos , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Masculino , Resultado do Tratamento , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
15.
Int J Food Microbiol ; 298: 1-10, 2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-30889473

RESUMO

Fresh betel leaves (Piper betle L.), imported into the UK are a traditional ready-to-eat food consumed by Asian populations. We report here the consolidation of routinely collected data to model the public health risks from consumption of this food. Amongst 2110 samples collected at Border Inspection, wholesale, catering or retail, Salmonella was detected in 488 (23%) of samples tested between 2011 and 2017 and was the most commonly Salmonella-contaminated ready-to-eat food examined by Public Health England during this period. Using data from multiple samples (usually 5) tested per consignment sampled at Border Inspection, contamination levels were calculated by most probable number: seasonal, temporal and country specific differences were detected. Quantitative contamination data was used to estimate the levels present at retail, and a ß-Poisson dose response model the probability of illness was calculated. Using data for products imported from India, the probability of acquiring infection following a single exposure (comprising of a single leaf) was estimated to be between 0.00003 (January-March) and 0.0001 (July-September). Using British Asian population data for individuals over 30 years of age in England in 2011, two estimates of consumption were modelled as 2.1 and 12.8 million servings per annum. Results from the model estimated 160 cases (range 102 to 242) and 960 cases (range 612 to 1456) per year in England for the two consumption estimates and equated to 34 (range 22 to 51) and 204 (range 130 to 310) salmonellosis cases per year reported to national surveillance. Salmonella from 475 of the contaminated samples were further characterised which showed a heterogeneous population structure with 46 S. enterica subsp. Enterica serovars, together with S. enterica subs diarizonae and salamae identified. Isolates from individual consignments were diverse and close genetic relationships between independent isolates were very rare except from within an individual consignment. There were no outbreaks detected as associated with betel leaf consumption. However analysis by whole genome sequencing of the 2014-17 data identified two cases where the clinical isolate had <5 single nucleotide polymorphism differences to isolates from betel leaves which is indicative of a likely epidemiological link and common source of contamination. Due to the diversity of the Salmonella contaminating this product, associations between salmonellosis cases and betel leaf consumption will appear sporadic and unlikely to be detected by current surveillance strategies based on outbreak detection.


Assuntos
Microbiologia de Alimentos , Modelos Estatísticos , Piper betle/microbiologia , Folhas de Planta/microbiologia , Saúde Pública/estatística & dados numéricos , Salmonella/fisiologia , Adulto , Inglaterra/epidemiologia , Humanos , Intoxicação Alimentar por Salmonella/prevenção & controle , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/prevenção & controle , Infecções por Salmonella/transmissão
16.
Clin Microbiol Infect ; 25(10): 1266-1276, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30790685

RESUMO

OBJECTIVES: Weekly monitoring of European all-cause excess mortality, the EuroMOMO network, observed high excess mortality during the influenza B/Yamagata dominated 2017/18 winter season, especially among elderly. We describe all-cause excess and influenza-attributable mortality during the season 2017/18 in Europe. METHODS: Based on weekly reporting of mortality from 24 European countries or sub-national regions, representing 60% of the European population excluding the Russian and Turkish parts of Europe, we estimated age stratified all-cause excess morality using the EuroMOMO model. In addition, age stratified all-cause influenza-attributable mortality was estimated using the FluMOMO algorithm, incorporating influenza activity based on clinical and virological surveillance data, and adjusting for extreme temperatures. RESULTS: Excess mortality was mainly attributable to influenza activity from December 2017 to April 2018, but also due to exceptionally low temperatures in February-March 2018. The pattern and extent of mortality excess was similar to the previous A(H3N2) dominated seasons, 2014/15 and 2016/17. The 2017/18 overall all-cause influenza-attributable mortality was estimated to be 25.4 (95%CI 25.0-25.8) per 100,000 population; 118.2 (116.4-119.9) for persons aged 65. Extending to the European population this translates into over-all 152,000 deaths. CONCLUSIONS: The high mortality among elderly was unexpected in an influenza B dominated season, which commonly are considered to cause mild illness, mainly among children. Even though A(H3N2) also circulated in the 2017/18 season and may have contributed to the excess mortality among the elderly, the common perception of influenza B only having a modest impact on excess mortality in the older population may need to be reconsidered.


Assuntos
Vírus da Influenza B/isolamento & purificação , Influenza Humana/mortalidade , Influenza Humana/virologia , Mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Europa (Continente)/epidemiologia , Feminino , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Skelet Muscle ; 9(1): 1, 2019 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-30611303

RESUMO

BACKGROUND: Niemann-Pick disease type A (NPDA), a disease caused by mutations in acid sphingomyelinase (ASM), involves severe neurodegeneration and early death. Intracellular lipid accumulation and plasma membrane alterations are implicated in the pathology. ASM is also linked to the mechanism of plasma membrane repair, so we investigated the impact of ASM deficiency in skeletal muscle, a tissue that undergoes frequent cycles of injury and repair in vivo. METHODS: Utilizing the NPDA/B mouse model ASM-/- and wild type (WT) littermates, we performed excitation-contraction coupling/Ca2+ mobilization and sarcolemma injury/repair assays with isolated flexor digitorum brevis fibers, proteomic analyses with quadriceps femoris, flexor digitorum brevis, and tibialis posterior muscle and in vivo tests of the contractile force (maximal isometric torque) of the quadriceps femoris muscle before and after eccentric contraction-induced muscle injury. RESULTS: ASM-/- flexor digitorum brevis fibers showed impaired excitation-contraction coupling compared to WT, a defect expressed as reduced tetanic [Ca2+]i in response to electrical stimulation and early failure in sustaining [Ca2+]i during repeated tetanic contractions. When injured mechanically by needle passage, ASM-/- flexor digitorum brevis fibers showed susceptibility to injury similar to WT, but a reduced ability to reseal the sarcolemma. Proteomic analyses revealed changes in a small group of skeletal muscle proteins as a consequence of ASM deficiency, with downregulation of calsequestrin occurring in the three different muscles analyzed. In vivo, the loss in maximal isometric torque of WT quadriceps femoris was similar immediately after and 2 min after injury. The loss in ASM-/- mice immediately after injury was similar to WT, but was markedly larger at 2 min after injury. CONCLUSIONS: Skeletal muscle fibers from ASM-/- mice have an impairment in intracellular Ca2+ handling that results in reduced Ca2+ mobilization and a more rapid decline in peak Ca2+ transients during repeated contraction-relaxation cycles. Isolated fibers show reduced ability to repair damage to the sarcolemma, and this is associated with an exaggerated deficit in force during recovery from an in vivo eccentric contraction-induced muscle injury. Our findings uncover the possibility that skeletal muscle functional defects may play a role in the pathology of NPDA/B disease.


Assuntos
Acoplamento Excitação-Contração , Músculo Esquelético/fisiopatologia , Doença de Niemann-Pick Tipo A/fisiopatologia , Doença de Niemann-Pick Tipo B/fisiopatologia , Sarcolema/fisiologia , Animais , Sinalização do Cálcio , Modelos Animais de Doenças , Feminino , Masculino , Camundongos Knockout , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Doença de Niemann-Pick Tipo A/metabolismo , Doença de Niemann-Pick Tipo B/metabolismo , Proteoma , Recuperação de Função Fisiológica , Sarcolema/metabolismo , Esfingomielina Fosfodiesterase/genética
18.
Epidemiol Infect ; 146(12): 1593-1601, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29909816

RESUMO

The present cross-sectional serosurvey constitutes the first effort to describe the varicella zoster virus (VZV) seroepidemiology in Serbia. An age-stratified serum bank of 3570 residual samples collected between 2015 and 2016 in each of the seven districts of the Vojvodina Province was tested for IgG anti-VZV antibodies with an enzyme immunoassay. Results were standardised into common units according to the European Sero-Epidemiology Network (ESEN2) methodology. Univariable and multivariable analyses were used to examine the relationships between standardised anti-VZV positivity or logarithmically transformed antibody titres and demographic features of study subjects. Seropositivity (85% overall) increased with age, in parallel with geometric mean titres. By the time of school entry, 68% of children were immune. The slower subsequent acquisition of immunity leaves epidemiologically relevant proportions of adolescents (7%), young adults (6%) and especially females of reproductive age (6%) prone to more severe forms of varicella. In the ongoing pre-vaccine era, natural infection provides a high level of collective immunity, with the highest VZV transmission in children of preschool age. The detected gaps in VZV immunity of the Serbian population support the adoption of the official recommendations for varicella immunisation of non-immune adolescents and young adults, including non-pregnant women of childbearing age.


Assuntos
Infecção pelo Vírus da Varicela-Zoster/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Técnicas Imunoenzimáticas , Lactente , Masculino , Pessoa de Meia-Idade , Sérvia/epidemiologia , Estudos Soroepidemiológicos
19.
Epidemiol Infect ; 146(9): 1106-1113, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29743125

RESUMO

Significant increases in excess all-cause mortality, particularly in the elderly, were observed during the winter of 2014/15 in England. With influenza A(H3N2) the dominant circulating influenza A subtype, this paper determines the contribution of influenza to this excess controlling for weather. A standardised multivariable Poisson regression model was employed with weekly all-cause deaths the dependent variable for the period 2008-2015. Adjusting for extreme temperature, a total of 26 542 (95% CI 25 301-27 804) deaths in 65+ and 1942 (95% CI 1834-2052) in 15-64-year-olds were associated with influenza from week 40, 2014 to week 20, 2015. This is compatible with the circulation of influenza A(H3N2). It is the largest estimated number of influenza-related deaths in England since prior to 2008/09. The findings highlight the potential health impact of influenza and the important role of the annual influenza vaccination programme that is required to protect the population including the elderly, who are vulnerable to a severe outcome.


Assuntos
Causas de Morte , Influenza Humana/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2 , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Estações do Ano , Temperatura , Adulto Jovem
20.
Vox Sang ; 113(4): 329-338, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29441589

RESUMO

BACKGROUND AND OBJECTIVES: The rate of confirmed hepatitis C virus (HCV) cases, in first-time donors, is much lower in 2015 than 20 years ago. We investigate reasons for the decline. MATERIALS AND METHODS: HCV rates were analysed by gender and birth cohort for 1996 to 2015 and ethnic group for 2006 to 2015. Variables for confirmed positive cases were compared for two ten-year periods (1996 to 2005 and 2006 to 2015) including genotyping data for 2006 to 2015. RESULTS: There were 2007 confirmed HCV cases identified between 1996 and 2015. The rate per 100 000 donations fell from 78·6 in 1996 to 26·9 by 2015. By birth cohort, HCV rates were highest in donors born in the 1950s and 1960s who contributed a decreasing proportion of first-time donors. Between 2006 and 2015, there was no significant decline in HCV rate. The HCV-positive donor profile has changed in the last 10 years with increased proportions of younger donors, donors born abroad and decreased reported injecting drug use. Genotype 1a remains predominate, but genotype 1b has increased associated with this change in birth cohort and ethnicity. CONCLUSION: The decline in number and rate of confirmed HCV-positive first-time donors is mainly due to a decrease in first-time donors born before 1970, with the highest rate of HCV. However, the decline has slowed and the profile of HCV-positive first-time donors is changing. A better understanding of behaviour and sources of HCV in younger and ethnic minority donors are needed.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Inglaterra , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/sangue , Humanos , Masculino , Testes Sorológicos , País de Gales
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