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1.
Osteoporos Int ; 33(8): 1815-1821, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35380213

RESUMO

Our aim was to evaluate the associations between the individual components of sarcopenia and fracture types. In this cohort, the risk of experiencing any clinical, hip, or major osteoporotic fracture is greater in men with slow walking speed in comparison to normal walking speed. INTRODUCTION: The association between the components of sarcopenia and fractures has not been clearly elucidated and has hindered the development of appropriate therapeutic interventions. Our aim was to evaluate the associations between the individual components of sarcopenia, specifically lean mass, strength, and physical performance and fracture (any fracture, hip fracture, major osteoporotic fracture) in the Osteoporotic Fractures in Men (MrOS) study. METHODS: The Osteoporotic Fractures in Men study (MrOS) recruited 5995 men ≥ 65 years of age. We measured appendicular lean mass (ALM) by dual-energy X-ray absorptiometry (low as residual value < 20th percentile for the cohort), walking speed (fastest trial of usual pace, values < 0.8 m/s were low), and grip strength (max score of 2 trials, values < 30 kg were low). Information on fractures was assessed tri-annually over an average follow-up of 12 years and centrally adjudicated. Cox proportional hazard models estimated the hazard ratio (HR) (95% confidence intervals) for slow walking speed, low grip strength, and low lean mass. RESULTS: Overall, 1413 men had a fracture during follow-up. Slow walking speed was associated with an increased risk for any HR = 1.39, 1.05-1.84; hip HR = 2.37, 1.54-3.63; and major osteoporotic, HR = 1.89, 1.34-2.67 in multi-variate-adjusted models. Low lean mass and low grip strength were not significantly associated with fracture. CONCLUSIONS: In this cohort of older adult men, the risk of experiencing any, hip, or major osteoporotic fracture is greater in men with slow walking speed in comparison to men with normal walking speed, but low grip strength and low lean mass were not associated with fracture.


Assuntos
Fraturas do Quadril , Fraturas por Osteoporose , Sarcopenia , Absorciometria de Fóton , Idoso , Feminino , Força da Mão , Fraturas do Quadril/complicações , Fraturas do Quadril/etiologia , Humanos , Masculino , Fraturas por Osteoporose/complicações , Fraturas por Osteoporose/etiologia , Sarcopenia/complicações
2.
Public Health ; 211: 85-87, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36058199

RESUMO

OBJECTIVE: To determine whether household contacts of confirmed cases of COVID-19 have an increased risk of hospitalisation or death. METHODS: We used the HOSTED data set of index cases of COVID-19 in England between June and November 2020, linked to Secondary Uses Service data on hospital episodes and Office for National Statistics' mortality data. Multivariable logistic regression models of the odds of household contacts being hospitalised or dying within six weeks of an index case, adjusted for case type, age, sex and calendar month were calculated. Excess risk was determined by comparing the first six weeks after the index case with 6-12 weeks after the index case in a survival analysis framework. RESULTS: Index cases were more likely to be hospitalised or die than either secondary cases or non-cases, having adjusted for age and sex. There was an increased risk of hospitalisation for non-cases (adjusted hazard ratio (aHR) 1.10; 95% confidence interval (CI) 1.04, 1.16) and of death (aHR 1.57; 95% CI 1.14, 2.16) in the first six weeks after an index case, compared to 6-12 weeks after. CONCLUSION: Risks of hospitalisation and mortality are predictably higher in cases compared to non-cases. The short-term increase in risks for non-case contacts following diagnosis of the index case may suggest incomplete case ascertainment among contacts, although this was relatively small.


Assuntos
COVID-19 , Características da Família , Hospitalização , Humanos , Modelos Logísticos , SARS-CoV-2
3.
Appl Opt ; 59(10): 3285-3295, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400613

RESUMO

We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.

4.
HIV Med ; 20(6): 377-391, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31034159

RESUMO

OBJECTIVES: Reliable and timely HIV care cost estimates are important for policy option appraisals of HIV treatment and prevention strategies. As HIV clinical management and outcomes have changed, we aimed to update profiles of antiretroviral (ARV) usage pattern, patent/market exclusivity details and management costs in adults (≥ 18 years old) accessing HIV specialist care in England. METHODS: The data reported quarterly to the HIV and AIDS Reporting System in England was used to identify ARV usage pattern, and were combined with British National Formulary (BNF) prices, non-ARV care costs and patent/market exclusivity information to generate average survival-adjusted lifetime care costs. The cumulative budget impact from 2018 to the year in which all current ARVs were expected to lose market exclusivity was calculated for a hypothetical 85 000 (± 5000) person cohort, which provided an illustration of potential financial savings afforded by bioequivalent generic switches. Price scenarios explored BNF70 (September 2015) prices and generics at 10/20/30/50% of proprietary prices. The analyses took National Health Service (NHS) England's perspective (as the payer), and results are presented in 2016/2017 British pounds. RESULTS: By 2033, most currently available ARVs would lose market exclusivity; that is, generics could be available. Average per person lifetime HIV cost was ~£200 000 (3.5% annual discount) or ~£400 000 (undiscounted), reducing to ~£70 000 (3.5% annual discount; ~£120 000 undiscounted) with the use of generics (assuming that generics cost 10% of proprietary prices). The cumulative budget to cover 85 000 (± 5000) persons for 16 years (2018-2033) was £10.5 (± 0.6) billion, reducing to £3.6 (± 0.2) billion with the use of generics. CONCLUSIONS: HIV management costs are high but financial efficiency could be improved by optimizing generic use for treatment and prevention to mitigate the high cost of lifelong HIV treatment. Earlier implementation of generics as they become available offers the potential to maximize the scale of the financial savings.


Assuntos
Gerenciamento Clínico , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Custos de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Epidemiol Infect ; 145(6): 1210-1220, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28095926

RESUMO

Human parainfluenza virus (HPIV) infections are one of the commonest causes of upper and lower respiratory tract infections. In order to determine if there have been any recent changes in HPIV epidemiology in England and Wales, laboratory surveillance data between 1998 and 2013 were analysed. The UK national laboratory surveillance database, LabBase, and the newly established laboratory-based virological surveillance system, the Respiratory DataMart System (RDMS), were used. Descriptive analysis was performed to examine the distribution of cases by year, age, sex and serotype, and to examine the overall temporal trend using the χ 2 test. A random-effects model was also employed to model the number of cases. Sixty-eight per cent of all HPIV detections were due to HPIV type 3 (HPIV-3). HPIV-3 infections were detected all year round but peaked annually between March and June. HPIV-1 and HPIV-2 circulated at lower levels accounting for 20% and 8%, respectively, peaking during the last quarter of the year with a biennial cycle. HPIV-4 was detected in smaller numbers, accounting for only 4% and also mainly observed in the last quarter of the year. However, in recent years, HPIV-4 detection has been reported much more commonly with an increase from 0% in 1998 to 3·7% in 2013. Although an overall higher proportion of HPIV infection was reported in infants (43·0%), a long-term decreasing trend in proportion in infants was observed. An increase was also observed in older age groups. Continuous surveillance will be important in tracking any future changes.


Assuntos
Infecções por Paramyxoviridae/epidemiologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Infecções por Paramyxoviridae/virologia , Prevalência , Infecções Respiratórias/virologia , Estações do Ano , Sorogrupo , Distribuição por Sexo , País de Gales/epidemiologia , Adulto Jovem
6.
Chem Soc Rev ; 45(16): 4533-51, 2016 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-27146712

RESUMO

Cationic gold complexes in which gold is bound to a formally divalent carbon atom, typically formulated as gold carbenes or α-metallocarbenium ions, have been widely invoked in a range of gold-catalyzed transformations, most notably in the gold-catalyzed cycloisomerization of 1,n-enynes. Although the existence of gold carbene complexes as intermediates in gold-catalyzed transformations is supported by a wealth of indirect experimental data and by computation, until recently no examples of cationic gold carbenes/α-metallocarbenium ions had been synthesized nor had any cationic intermediates generated via gold-catalyzed enyne cycloaddition been directly observed. Largely for this reason, there has been considerable debate regarding the electronic structure of these cationic complexes, in particular the relative contributions of the carbene (LAu(+)[double bond, length as m-dash]CR2) and α-metallocarbenium (LAu-CR2(+)) forms, which is intimately related to the extent of d → p backbonding from gold to the C1 carbon atom. However, over the past ∼ seven years, a number of cationic gold carbene complexes have been synthesized in solution and generated in the gas phase and cationic intermediates have been directly observed in the gold-catalyzed cycloaddition of enynes. Together, these advances provide insight into the nature and electronic structure of gold carbene/α-metallocarbenium complexes and the cationic intermediates generated via gold-catalyzed enyne cycloaddition. Herein we review recent advances in this area.

7.
Thorax ; 71(10): 940-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27298314

RESUMO

INTRODUCTION: Consensus on the best treatment regimens for patients with isoniazid-resistant TB is limited; global treatment guidelines differ. We undertook a systematic review and meta-analysis using mixed-treatment comparisons methodology to provide an up-to-date summary of randomised controlled trials (RCTs) and relative regimen efficacy. METHODS: Ovid MEDLINE, the Web of Science and EMBASE were mined using search terms for TB, drug therapy and RCTs. Extracted data were inputted into fixed-effects and random-effects models. ORs for all possible network comparisons and hierarchical rankings for different regimens were obtained. RESULTS: 12 604 records were retrieved and 118 remained postextraction, representing 59 studies-27 standalone and 32 with multiple papers. In comparison to a baseline category that included the WHO-recommended regimen for countries with high levels of isoniazid resistance (rifampicin-containing regimens using fewer than three effective drugs at 4 months, in which rifampicin was protected by another effective drug at 6 months, and rifampicin was taken for 6 months), extending the duration of rifampicin and increasing the number of effective drugs at 4 months lowered the odds of unfavourable outcomes (treatment failure or the lack of microbiological cure; relapse post-treatment; death due to TB) in a fixed-effects model (OR 0.31 (95% credible interval 0.12-0.81)). In a random-effects model all estimates crossed the null. CONCLUSIONS: Our systematic review and network meta-analysis highlight a regimen category that may be more efficacious than the WHO population level recommendation, and identify knowledge gaps where data are sparse. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42014015025.


Assuntos
Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana , Isoniazida/uso terapêutico , Tuberculose/tratamento farmacológico , Antituberculosos/farmacologia , Quimioterapia Combinada , Humanos , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
8.
J Viral Hepat ; 23(8): 631-43, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27025238

RESUMO

New direct-acting antivirals have the potential to transform the hepatitis C (HCV) treatment landscape, with rates of sustained viral response in excess of 90%. As these new agents are expensive, an important question is whether to focus on minimizing the consequences of severe liver disease, or reducing transmission via 'treatment as prevention'. A back-calculation model was used to estimate the impact of treatment of mild, moderate and compensated cirrhosis on incident cases of HCV-related end-stage liver disease/hepatocellular carcinoma (ESLD/HCC). In addition, a dynamic model was used to determine the impact on incidence and prevalence of chronic infection in people who inject drugs (PWID), the main risk group in England. Treating 3500 cirrhotics per year was predicted to reduce ESLD/HCC incidence from 1100 (95% CrI 970-1240) cases per year in 2015 to 630 (95% CrI 530-770) in 2020, around half that currently expected, although treating moderate-stage disease will also be needed to sustain this reduction. Treating mild-stage PWID was required to make a substantial impact on transmission: with 2500 treated per year, chronic prevalence/annual incidence in PWID was reduced from 34%/4.8% in 2015 to 11%/1.4% in 2030. There was little overlap between the two goals: treating mild stage had virtually no impact on ESLD/HCC within 15 years, but the long timescale of liver disease means relatively few PWID reach cirrhosis before cessation of injecting. Strategies focussing on treating advanced disease have the potential for dramatic reductions in severe morbidity, but virtually no preventative impact.


Assuntos
Antivirais/uso terapêutico , Quimioprevenção/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/prevenção & controle , Inglaterra , Hepatite C Crônica/transmissão , Humanos , Incidência , Modelos Estatísticos , Prevalência , Resultado do Tratamento
9.
Epidemiol Infect ; 143(16): 3375-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25850904

RESUMO

The relationship between risk of death following influenza A(H1N1)pdm09 infection and ethnicity and deprivation during the 2009/2010 pandemic period and the first post-pandemic season of 2010/2011 in England was examined. Poisson regression models were used to estimate the mortality risk, adjusted for age, gender, and place of residence. Those of non-White ethnicity experienced an increased mortality risk compared to White populations during the 2009/2010 pandemic [10·5/1000 vs. 6·0/1000 general population; adjusted risk ratio (RR) 1·84, 95% confidence interval (CI) 1·39-2·54] with the highest risk in those of Pakistani ethnicity. However, no significant difference between ethnicities was observed during the following 2010/2011 season. Persons living in areas with the highest level of deprivation had a significantly higher risk of death (RR 2·08, 95% CI 1·49-2·91) compared to the lowest level for both periods. These results highlight the importance of rapid identification of groups at higher risk of severe disease in the early stages of future pandemics to enable the implementation of optimal prevention and control measures for vulnerable populations.


Assuntos
Etnicidade , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Influenza Humana/patologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Análise de Sobrevida , Adulto Jovem
10.
Epidemiol Infect ; 142(1): 211-20, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23561246

RESUMO

Data obtained from genitourinary medicine clinics through a comprehensive surveillance system were used in a Bayesian mixed-effects Poisson regression model to explore socio-demographic individual and ecological risk factors for gonorrhoea in London, as well as its spatial clustering. The spatial analysis was performed at the Middle-layer Super Output Area level (median population size 7200). A total of 12452 individuals were diagnosed during the 2-year study period (2009-2010). The study confirmed the presence of 'core areas' of high incidence, and identified 'core' high-risk groups, in particular young adults (16-29 years), males, black Caribbeans and more deprived areas. The individual (age, sex, ethnicity) and area-level (deprivation, teenage pregnancies, students) model covariates accounted for 48% of the variance. Most of the remaining variance was explained by the spatial effect, thus capturing other spatially distributed factors associated with gonorrhoea, such as local sexual networks. These findings will be useful in identifying areas for targeted interventions, such as STI testing and health promotion.


Assuntos
Gonorreia/epidemiologia , Adolescente , Adulto , Idoso , Teorema de Bayes , Análise por Conglomerados , Estudos de Coortes , Feminino , Humanos , Incidência , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Vigilância em Saúde Pública
11.
Euro Surveill ; 19(14)2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24739984

RESUMO

Responses to injecting drug use have changed focus over the last 20 years. Prevalence and incidence of human immunodeficiency virus (HIV) among people who inject drugs (PWID) in England and Wales were examined in relation to these changes. A voluntary unlinked-anonymous surveillance study obtained a biological sample and questionnaire data from PWID through annual surveys since 1990. Prevalence and incidence trends were estimated via generalised linear models, and compared with a policy time-line. Overall HIV prevalence among 38,539 participations was 1.15%. Prevalence was highest among those who started injecting before 1985; throughout the 1990s, prevalence fell in this group and was stable among those who started injecting later. Prevalence was higher in 2005 than 2000 (odds ratio: 3.56 (95% confidence interval (CI) 1.40­9.03) in London, 3.40 (95% CI 2.31­5.02) elsewhere). Estimated HIV incidence peaked twice, around 1983 and 2005. HIV was an important focus of policy concerning PWID from 1984 until 1998. This focus shifted at a time when drug use and risk were changing. The increased incidence in 2005 cannot be ascribed to the policy changes, but these appeared to be temporally aligned. Policy related to PWID should be continually reviewed to ensure rapid responses to increased risk.


Assuntos
Usuários de Drogas/estatística & dados numéricos , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Intervalos de Confiança , Usuários de Drogas/psicologia , Inglaterra/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Abuso de Substâncias por Via Intravenosa/prevenção & controle , Inquéritos e Questionários , Fatores de Tempo , País de Gales/epidemiologia , Adulto Jovem
12.
HIV Med ; 13(2): 89-97, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21819529

RESUMO

BACKGROUND: We examined whether determinants of disease progression and causes of death differ between injecting drug users (IDUs) and non-IDUs who initiate combination antiretroviral therapy (cART). METHODS: The ART Cohort Collaboration combines data from participating cohort studies on cART-naïve adults from cART initiation. We used Cox models to estimate hazard ratios for death and AIDS among IDUs and non-IDUs. The cumulative incidence of specific causes of death was calculated and compared using methods that allow for competing risks. RESULTS: Data on 6269 IDUs and 37 774 non-IDUs were analysed. Compared with non-IDUs, a lower proportion of IDUs initiated cART with a CD4 cell count <200 cells/µL or had a prior diagnosis of AIDS. Mortality rates were higher in IDUs than in non-IDUs (2.08 vs. 1.04 per 100 person-years, respectively; P<0.001). Lower baseline CD4 cell count, higher baseline HIV viral load, clinical AIDS at baseline, and later year of cART initiation were associated with disease progression in both groups. However, the inverse association of baseline CD4 cell count with AIDS and death appeared stronger in non-IDUs than in IDUs. The risk of death from each specific cause was higher in IDUs than non-IDUs, with particularly marked increases in risk for liver-related deaths, and those from violence and non-AIDS infection. CONCLUSION: While liver-related deaths and deaths from direct effects of substance abuse appear to explain much of the excess mortality in IDUs, they are at increased risk for many other causes of death, which may relate to suboptimal management of HIV disease in these individuals.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Usuários de Drogas/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/mortalidade , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Adolescente , Adulto , Contagem de Linfócito CD4 , Estudos de Coortes , Progressão da Doença , Quimioterapia Combinada , Feminino , Infecções por HIV/etiologia , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Modelos de Riscos Proporcionais , RNA Viral/sangue , Fatores de Risco , Carga Viral , Adulto Jovem
13.
Opt Lett ; 37(12): 2331-3, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22739898

RESUMO

Using ultrafast laser inscription, we report the fabrication of a prototype three-dimensional 121-waveguide fan-out device capable of reformatting the output of a 120-core multicore fiber (MCF) into a one-dimensional linear array. When used in conjunction with an actual MCF, we demonstrate that the reformatting function using this prototype would result in an overall through put loss of ≈7.0 dB. However, if perfect coupling from the MCF into the fan-out could be achieved, the reformatting function would result in an overall loss of only ≈1.7 dB. With adequate development, similar devices could efficiently reformat the output of so-called "photonic lanterns" fabricated using highly multicore fibers.

14.
Epidemiol Infect ; 140(6): 1054-63, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21875456

RESUMO

In developed countries the majority of hepatitis C virus (HCV) infections occur in injecting drug users (IDUs) with prevalence in IDUs often high, but with wide geographical differences within countries. Estimates of local prevalence are needed for planning services for IDUs, but it is not practical to conduct HCV seroprevalence surveys in all areas. In this study survey data from IDUs attending specialist services were collected in 52/149 sites in England between 2006 and 2008. Spatially correlated random-effects models were used to estimate HCV prevalence for all sites, using auxiliary data to aid prediction. Estimates ranged from 14% to 82%, with larger cities, London and the North West having the highest HCV prevalence. The methods used generated robust estimates for each area, with a well-identified spatial pattern that improved predictions. Such models may be of use in other areas of study where surveillance data are sparse.


Assuntos
Hepatite C/epidemiologia , Hepatite C/etiologia , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adolescente , Adulto , Feminino , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Razão de Chances , Prevalência , Estudos Soroepidemiológicos , Reino Unido/epidemiologia , Adulto Jovem
15.
HIV Med ; 12(4): 250-4, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21371237

RESUMO

OBJECTIVES: The aim of the study was to estimate the levels of transmitted drug resistance (TDR) in HIV-1 using very sensitive assays to detect minority drug-resistant populations. METHODS: We tested unlinked anonymous serum specimens from sexual health clinic attendees, who had not received an HIV diagnosis at the time of sampling, by both standard genotyping and using minority detection assays. RESULTS: By standard genotyping, 21 of 165 specimens (12.7%) showed evidence of drug resistance, while, using a combination of standard genotyping and minority mutation assays targeting three commonly observed drug resistance mutations which cause high-level resistance to commonly prescribed first-line antiretroviral therapy (ART), this rose to 32 of 165 (19.4%). This increase of 45% in drug resistance levels [95% confidence interval (CI) 15.2-83.7%; P=0.002] was statistically significant. Almost all of this increase was accounted for by additional detections of the M184V mutation. CONCLUSIONS: Future surveillance studies of TDR in the United Kingdom should consider combining standard genotyping and minority-specific assays to provide more accurate estimates, particularly when using specimens collected from chronic HIV infections in which TDR variants may have declined to low levels.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/genética , Testes de Mutagenicidade/métodos , Farmacorresistência Viral/efeitos dos fármacos , Feminino , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Transcriptase Reversa do HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Humanos , Masculino , Mutação , Reino Unido
16.
Int J Epidemiol ; 50(3): 743-752, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837417

RESUMO

BACKGROUND: Household transmission of SARS-CoV-2 is an important component of the community spread of the pandemic. Little is known about the factors associated with household transmission, at the level of the case, contact or household, or how these have varied over the course of the pandemic. METHODS: The Household Transmission Evaluation Dataset (HOSTED) is a passive surveillance system linking laboratory-confirmed COVID-19 cases to individuals living in the same household in England. We explored the risk of household transmission according to: age of case and contact, sex, region, deprivation, month and household composition between April and September 2020, building a multivariate model. RESULTS: In the period studied, on average, 5.5% of household contacts in England were diagnosed as cases. Household transmission was most common between adult cases and contacts of a similar age. There was some evidence of lower transmission rates to under-16s [adjusted odds ratios (aOR) 0.70, 95% confidence interval (CI) 0.66-0.74). There were clear regional differences, with higher rates of household transmission in the north of England and the Midlands. Less deprived areas had a lower risk of household transmission. After controlling for region, there was no effect of deprivation, but houses of multiple occupancy had lower rates of household transmission [aOR 0.74 (0.66-0.83)]. CONCLUSIONS: Children are less likely to acquire SARS-CoV-2 via household transmission, and consequently there was no difference in the risk of transmission in households with children. Households in which cases could isolate effectively, such as houses of multiple occupancy, had lower rates of household transmission. Policies to support the effective isolation of cases from their household contacts could lower the level of household transmission.


Assuntos
COVID-19 , Adulto , Criança , Inglaterra/epidemiologia , Características da Família , Humanos , Pandemias , SARS-CoV-2
17.
Water Res ; 171: 115441, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31927090

RESUMO

This study is an analysis of relationships between microalgae (measured as chlorophyll a) and the fecal indicator bacteria enterococci. Microalgae blooms and enterococci exceedances have been occurring in Florida's recreational waterways for years. More recently, this has become a management concern as microalgae blooms have been attributed to potentially toxic cyanobacteria, and enterococci exceedances link to human infection/illness. Since both the microalgal blooms and bacterial exceedances occur in regions that receive managed freshwater releases from Lake Okeechobee, we hypothesized that both the blooms and exceedances are related to excess nutrients from the lake. Two experimental sites, on Lake Okeechobee and the St. Lucie River (downstream of the lake), plus a control site on the Loxahatchee River (which does not receive lake flow) were evaluated. The hypothesis was evaluated through three study components: 1) analysis of available long-term data from local environmental databases, 2) a year-long monthly sampling and analysis of chlorophyll a, enterococci, nutrients, and physical-chemical data, and 3) microcosm experiments with altered water/sediment conditions. Results support the hypothesis that excess nutrients play a role in both chlorophyll a and enterococci levels. For the St. Lucie River, analyses indicate that chlorophyll a correlated significantly with total Kjeldahl nitrogen (TKN) (R2 = 0.30, p = 0.008) and the strongest model for enterococci included nitrate-nitrite, TKN, total phosphorus, orthophosphorus, and turbidity in our long-term analysis (n = 39, R2 = 0.83, p ≤ 0.001). The microcosm results indicated that chlorophyll a and enterococci only persisted for 36 h in water from all sources, and that sediments from Lake Okeechobee may have allowed for sustained levels of chlorophyll a and enterococci levels. Overall similarities were observed in chlorophyll a and enterococci relationships with nutrient concentrations regardless of a Lake Okeechobee connection, as underscored by a study of flow out of the lake and downstream areas. This suggests that both nutrient-rich lake water and untreated surface water runoff contribute to microalgae blooms and enterococci exceedances in southeast Florida.


Assuntos
Lagos , Microalgas , Proliferação de Células , Clorofila , Clorofila A , Enterococcus , Monitoramento Ambiental , Eutrofização , Florida , Nitrogênio , Fósforo
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(3 Pt 1): 031104, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17500665

RESUMO

Motivated by mapping from a stochastic system with spatially random rates, we consider disordered non-conserving free-fermion systems using a scaling procedure for the equations of motion. This approach demonstrates disorder-induced localization acting in competition with the asymmetric driving. We discuss the resulting implications for the original stochastic system.

19.
Leukemia ; 19(4): 524-30, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15674425

RESUMO

CD154 is an important regulator of chronic lymphocytic leukaemia (CLL)-cell survival. In CLL, high serum levels of VEGF are a feature of advanced disease, and we and others have previously shown that CLL cells produce and secrete this growth factor. Since CD154 stimulates VEGF production in other cell types, and VEGF is known to promote cell survival, we examined whether the cytoprotection of CLL cells by CD154 involves VEGF. We report for the first time that treatment of CLL cells with CD154 results in increased VEGF production and demonstrate involvement of NF-kappaB in this process. Moreover, we show that CD154-induced CLL-cell survival is reduced by anti-VEGF-neutralising antibody and by inhibiting VEGF receptor (VEGFR) signalling with SU5416. However, addition of exogenous VEGF alone or blocking secreted autocrine VEGF had little or no effect on CLL-cell survival. We therefore conclude that CLL-cell cytoprotection in the presence of CD154 requires combined signalling by both CD40 and VEGFR. This combined signalling and resulting cytoprotection were shown to involve NF-kappaB activation and increased survivin production. In conclusion, our findings identify autocrine VEGF as an important mediator of the antiapoptotic effect of CD40 ligation, and thus provide new insights into CLL-cell rescue by CD154 in lymphoreticular tissues.


Assuntos
Apoptose/fisiologia , Ligante de CD40/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Comunicação Autócrina , Sobrevivência Celular/fisiologia , Humanos , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/metabolismo , NF-kappa B/metabolismo , Proteínas de Neoplasias , Transdução de Sinais/fisiologia , Survivina , Células Tumorais Cultivadas , Regulação para Cima
20.
Int J Tuberc Lung Dis ; 20(7): 866-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27287636

RESUMO

Treatment guidance for non-multidrug-resistant (MDR) rifampicin-resistant (RMP-R) tuberculosis (TB) is variable. We aimed to undertake a systematic review and meta-analysis of the randomised controlled trial (RCT) data behind such guidelines to identify the most efficacious treatment regimens. Ovid MEDLINE, the Web of Science and EMBASE were mined using search terms for TB, drug therapy and RCTs. Despite 12 604 records being retrieved, only three studies reported treatment outcomes by regimen for patients with non-MDR RMP-R disease, preventing meta-analysis. Our systematic review highlights a substantial gap in the literature regarding evidence-based treatment regimens for RMP-R TB.


Assuntos
Antibióticos Antituberculose/uso terapêutico , Pesquisa Biomédica/métodos , Farmacorresistência Bacteriana , Lacunas da Prática Profissional/métodos , Rifampina/uso terapêutico , Tuberculose/tratamento farmacológico , Medicina Baseada em Evidências , Humanos , Testes de Sensibilidade Microbiana , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Tuberculose/diagnóstico , Tuberculose/microbiologia
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