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1.
Nature ; 613(7945): 662-666, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36697865

RESUMO

Field emission of electrons underlies great advances in science and technology, ranging from signal processing at ever higher frequencies1 to imaging of the atomic-scale structure of matter2 with picometre resolution. The advancing of electron microscopy techniques to enable the complete visualization of matter on the native spatial (picometre) and temporal (attosecond) scales of electron dynamics calls for techniques that can confine and examine the field emission on sub-femtosecond time intervals. Intense laser pulses have paved the way to this end3,4 by demonstrating femtosecond confinement5,6 and sub-optical cycle control7,8 of the optical field emission9 from nanostructured metals. Yet the measurement of attosecond electron pulses has remained elusive. We used intense, sub-cycle light transients to induce optical field emission of electron pulses from tungsten nanotips and a weak replica of the same transient to directly investigate the emission dynamics in real time. Access to the temporal properties of the electron pulses rescattering off the tip surface, including the duration τ = (53 as ± 5 as) and chirp, and the direct exploration of nanoscale near fields open new prospects for research and applications at the interface of attosecond physics and nano-optics.

2.
Phys Rev Lett ; 131(2): 023001, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505945

RESUMO

Ionization of matter by energetic radiation generally causes complex secondary reactions that are hard to decipher. Using large helium nanodroplets irradiated by extreme ultraviolet (XUV) photons, we show that the full chain of processes ensuing primary photoionization can be tracked in detail by means of high-resolution electron spectroscopy. We find that elastic and inelastic scattering of photoelectrons efficiently induces interatomic Coulombic decay (ICD) in the droplets. This type of indirect ICD even becomes the dominant process of electron emission in nearly the entire XUV range in large droplets with radius ≳40 nm. Indirect ICD processes induced by electron scattering likely play an important role in other condensed-phase systems exposed to ionizing radiation as well, including biological matter.

3.
Biometrics ; 79(3): 1701-1712, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36471903

RESUMO

We propose and study a simple and innovative non-parametric approach to estimate the age-of-onset distribution for a disease from a cross-sectional sample of the population that includes individuals with prevalent disease. First, we estimate the joint distribution of two event times, the age of disease onset and the survival time after disease onset. We accommodate that individuals had to be alive at the time of the study by conditioning on their survival until the age at sampling. We propose a computationally efficient expectation-maximization (EM) algorithm and derive the asymptotic properties of the resulting estimates. From these joint probabilities we then obtain non-parametric estimates of the age-at-onset distribution by marginalizing over the survival time after disease onset to death. The method accommodates categorical covariates and can be used to obtain unbiased estimates of the covariate distribution in the source population. We show in simulations that our method performs well in finite samples even under large amounts of truncation for prevalent cases. We apply the proposed method to data from female participants in the Washington Ashkenazi Study to estimate the age-at-onset distribution of breast cancer associated with carrying BRCA1 or BRCA2 mutations.


Assuntos
Idade de Início , Humanos , Feminino , Estudos Transversais , Probabilidade , Causalidade , Washington
4.
BMC Pregnancy Childbirth ; 23(1): 823, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017404

RESUMO

BACKGROUND: The United Kingdom (UK) has committed to the World Health Organization's viral hepatitis elimination targets. New case finding strategies, such as antenatal testing, may be needed to achieve these targets. We conducted a rapid review to understand hepatitis C-specific antibody (anti-HCV) and HCV RNA test positivity in antenatal settings in the United Kingdom to inform guidance. METHODS: Articles and conference abstracts published between January 2000 and June 2022 reporting anti-HCV testing in antenatal settings were identified through PubMed and Web of Science searches. Results were synthesised using a narrative approach. RESULTS: The search identified 2,011 publications; 10 studies were included in the final synthesis. Seven studies used anonymous testing methods and three studies used universal opt-out testing. Anti-HCV test positivity ranged from 0.1 to 0.99%, with a median value of 0.38%. Five studies reported HCV RNA positivity, which ranged from 0.1 to 0.57% of the testing population, with a median value of 0.22%. One study reported cost effectiveness of HCV and found it to be cost effective at £9,139 per quality adjusted life years. CONCLUSION: The relative contribution of universal opt-out antenatal testing for HCV should be reconsidered, as antenatal testing could play an important role in new case-finding and aid achieving elimination targets.


Assuntos
Hepacivirus , Hepatite C , Humanos , Feminino , Gravidez , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Diagnóstico Pré-Natal , Análise Custo-Benefício , RNA , Reino Unido
5.
Phys Chem Chem Phys ; 24(5): 2944-2957, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35076648

RESUMO

The fragmentation dynamics of the gas-phase, doubly charged camphor molecule, formed by Auger decay following carbon 1s ionisation, using soft X-ray synchrotron radiation, is presented in this work. The technique of velocity map imaging combined with a photoelectron-photoion-photoion coincidence (VMI-PEPIPICO) is used for both electron energy and ion momentum (in-sequence) measurements. The experimental study is complemented by molecular dynamics simulation, performed with an NVT (moles, volume, and temperature) ensemble. Velocity Verlet algorithms were used for time integration at various internal energies. These simulations validate observed dissociation pathways. From these, we successfully deduce that the internal energy of the doubly charged molecular ion has a significant contribution to the fragmentation mechanism. Notably, a prominent signature of the internal energy was observed in the experimentally determined energies of the neutral fragment in these deferred charge separation pathways, entailing a more detailed theoretical study to uncover the exact dissociation dynamics.

6.
Phys Chem Chem Phys ; 24(47): 28844-28852, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36422471

RESUMO

Superfluid helium nanodroplets are often considered as transparent and chemically inert nanometer-sized cryo-matrices for high-resolution or time-resolved spectroscopy of embedded molecules and clusters. On the other hand, when the helium nanodroplets are resonantly excited with XUV radiation, a multitude of ultrafast processes are initiated, such as relaxation into metastable states, formation of nanoscopic bubbles or excimers, and autoionization channels generating low-energy free electrons. Here, we discuss the full spectrum of ultrafast relaxation processes observed when helium nanodroplets are electronically excited. In particular, we perform an in-depth study of the relaxation dynamics occurring in the lowest 1s2s and 1s2p droplet bands using high resolution, time-resolved photoelectron spectroscopy. The simplified excitation scheme and improved resolution allow us to identify the relaxation into metastable triplet and excimer states even when exciting below the droplets' autoionization threshold, unobserved in previous studies.

7.
Environ Monit Assess ; 194(9): 643, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930070

RESUMO

The present study demonstrates the spatial analysis and mapping of fish and different measures of environmental parameters and fish diversity of Pong reservoir, Himachal Pradesh, using Kriging spatial interpolation methods for geographical information system mapping. Seasonal data on environmental parameters, potential fish habitat and fish diversity was collected from lentic (dam), lentic (reservoir), transitional and lotic zone of the reservoir.. Important environmental parameters like water temperature, dissolved oxygen, electrical conductivity, water depth and transparency showed variations across the different zones of the reservoir. The sediment of the reservoir was sandy clay loam in nature as per texture analysis. Fish species richness, Shannon index and evenness index showed a similarity of the lotic and lentic (reservoir) zones of the reservoir. Six potential fish breeding grounds were identified in the reservoir indicating high conservation significance. The analysis of data showed a declining trend in fish production from 456.9 tonnes during the decade 1976-1987 to 347.91 tonnes during 2009-2020. The factors like anthropogenic climate change, predation of a stocked fish juvenile by water birds, undersized fish stocking and unscientific management are the probable reasons for the decreasing fish production. The spatial variation pattern of the water spread area, environmental parameters, fish catch and potential fish breeding grounds depicted in the GIS platform can be used as an important information base by the policy makers for fisheries management. The stocking of large size fish as a stocking material and adequate protection of the potential fish breeding grounds are the key advisories for the sustainable enhancement of fisheries as well as conservation.


Assuntos
Biodiversidade , Sistemas de Informação Geográfica , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Água
8.
Faraday Discuss ; 228(0): 242-265, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-33687396

RESUMO

The acetylene-vinylidene system serves as a benchmark for investigations of ultrafast dynamical processes where the coupling of the electronic and nuclear degrees of freedom provides a fertile playground to explore the femto- and sub-femto-second physics with coherent extreme-ultraviolet (EUV) photon sources both on the table-top as well as free-electron lasers. We focus on detailed investigations of this molecular system in the photon energy range 19-40 eV where EUV pulses can probe the dynamics effectively. We employ photoelectron-photoion coincidence (PEPICO) spectroscopy to uncover hitherto unrevealed aspects of this system. In this work, the role of excited states of the C2H2+ cation, the primary photoion, is specifically addressed. From photoelectron energy spectra and angular distributions, the nature of the dissociation and isomerization channels is discerned. Exploiting the 4π-collection geometry of the velocity map imaging spectrometer, we not only probe pathways where the efficiency of photoionization is inherently high but also perform PEPICO spectroscopy on relatively weak channels.

9.
J Environ Manage ; 285: 112116, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581456

RESUMO

Air pollution due to dust emission is continuously increasing day by day in mining and allied industrial areas. Mining operations contribute a substantial amount of dust emission at the crushing, screening, and bulk material handling in loading areas. The ambient suspended dust particles create a severe nuisance to workers and local dwellers. For effective controlling of positive dust emission, an innovative automated dry fog dust suppression system (DFDSS) has been developed using hybrid nozzles, sensors, actuators, controllers, screw compressors, air receivers, pumps, motors, and water arrangement with filtration facility. The DFDSS was installed in a crushing and screening plant of an iron ore mine in India. Performance study indicted fugitive dust emission concentration values ranged from 354 to 7040 µg m-3, which was reduced to 91-300 µg m-3 after installation of DFDSS. The reduced values were within the permissible limit of 1200 µg m-3 at a distance of 25 ± 2 m in the predominant downwind direction. The installed DFDSS added a meager addition of moisture content of 0.032% in the handling iron ore material, which was below the acceptable limit of 0.1%. The DFDSS precisely regulated fugitive dust emission from various mining activities without affecting the minerals processing performance. Thus, the DFDSS can be implemented effectively in different mining and allied industries where there is a dust emission problem.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Poeira/análise , Monitoramento Ambiental , Humanos , Índia , Mineração
10.
Phys Rev Lett ; 125(12): 123902, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016708

RESUMO

We consider exciton polaritons in a zigzag chain of coupled elliptical micropillars subjected to incoherent excitation. The driven-dissipative nature of the system along with the naturally present polarization splitting inside the pillars gives rise to nonreciprocal dynamics, which eventually leads to the non-Hermitian skin effect, where all the modes of the system collapse to one edge. As a result, the polaritons propagate only in one direction along the chain, independent of the excitation position, and the propagation in the opposite direction is suppressed. The system shows robustness against disorder and, using the bistable nature of polaritons to encode information, we show one-way information transfer. This paves the way for compact and robust feedback-free one-dimensional polariton transmission channels without the need for external magnetic field, which are compatible with proposals for polaritonic circuits.

11.
Phys Rev Lett ; 124(6): 063901, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109115

RESUMO

Recently realized higher order topological insulators have taken a surge of interest among the theoretical and experimental condensed matter community. The two-dimensional second order topological insulators give rise to zero-dimensional localized corner modes that reside within the band gap of the system along with edge modes that inhabit a band edge next to bulk modes. Thanks to the topological nature, information can be trapped at the corners of these systems, which will be unhampered even in the presence of disorder. Being localized at the corners, the exchange of information among the corner states is an issue. Here we show that the nonlinearity in an exciton polariton system can allow the coupling between the different corners through the edge states based on optical parametric scattering, realizing a system of multiple connectible topological modes.

12.
Phys Chem Chem Phys ; 22(18): 10149-10157, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32347252

RESUMO

Embedded atoms or molecules in a photoexcited He nanodroplet are well-known to be ionized through inter-atomic relaxation in a Penning process. In this work, we investigate the Penning ionization of acetylene oligomers occurring from the photoexcitation bands of He nanodroplets. In close analogy to conventional Penning electron spectroscopy by thermal atomic collisions, the n = 2 photoexcitation band plays the role of the metastable atomic 1s2s 3,1S He*. This facilitates electron spectroscopy of acetylene aggregates in the sub-Kelvin He environment, providing the following insight into their structure: the molecules in the dopant cluster are loosely bound van der Waals complexes rather than forming covalent compounds. In addition, this work reveals a Penning process stemming from the n = 4 band where charge-transfer from autoionized He in the droplets is known to be the dominant relaxation channel. This allows for excited states of the remnant dopant oligomer Penning-ions to be studied. Hence, we demonstrate Penning ionization electron spectroscopy of doped droplets as an effective technique for investigating dopant oligomers which are easily formed by attachment to the host cluster.

13.
Phys Chem Chem Phys ; 22(16): 8557-8564, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32255091

RESUMO

Alkali metal dimers attached to the surface of helium nanodroplets are found to be efficiently doubly ionized by electron transfer mediated decay (ETMD) when photoionizing the helium droplets. This process is evidenced by detecting in coincidence two energetic ions created by Coulomb explosion and one low-kinetic energy electron. The kinetic energy spectra of ions and electrons are reproduced by simple model calculations based on diatomic potential energy curves, and are in agreement with ab initio calculations for the He-Na2 and He-KRb systems. This work demonstrates that ETMD is an important decay channel in heterogeneous nanosystems exposed to ionizing radiation.

14.
Ann Hum Biol ; 47(5): 490-497, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32605398

RESUMO

BACKGROUND: The Jat Sikh population is the largest endogamous group of Punjab, a state in north-west India, and has not yet been explored for genetic polymorphism based on X-STR genetic markers. In India, which is the second most populous country in the world, only two population studies based on X-STR markers have been reported so far. AIM: To explore the genetic diversity of 12 X chromosomal STR genetic markers in the Jat Sikh population of Punjab and expand the X-STR polymorphism database. SUBJECTS AND METHODS: In this study, a total of 200 Jat Sikh individuals (100 males and 100 females) residing in Punjab were investigated for 12 X-STR markers using the Investigator Argus X-12 QS Kit. RESULTS: The highest power of discrimination (PD) in females (PDf) and males (PDm) was observed to be 0.965 (DXS10135) and 0.929 (DXS10135 and DXS10148), respectively. DXS10135 was found to be the most polymorphic and discriminating locus among all the studied loci in both males and females with highest values of power of discrimination (PD) and polymorphic information content (PIC) as well. CONCLUSION: Overall, the studied markers of the Argus 12 X-STR kit provide high polymorphic information which may prove to be an important tool in resolving issues such as missing person identification, incest, immigration disputes, kinship analysis and genealogical studies. The dataset obtained from this study will add to the present database of X-STRs.


Assuntos
Cromossomos Humanos X/genética , Marcadores Genéticos , Variação Genética , Genoma Humano , Repetições de Microssatélites , Feminino , Genótipo , Humanos , Índia , Masculino
15.
HIV Med ; 20(4): 255-263, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30693643

RESUMO

OBJECTIVES: The aim of the study was to estimate HIV prevalence among persons with hepatitis B virus (HBV) infection in England and to examine associated risk factors. METHODS: Persons aged ≥ 15 years with an HBV surface antigen (HBsAg) test reported to Public Health England (PHE) sentinel surveillance during 2008-2014 were linked to the PHE national HIV/AIDS database. Coinfection was defined as an HIV diagnosis prior to, or within 6 months following, a positive HBsAg test. RESULTS: During 2008-2014, 2 149 933 persons were tested for HBsAg and 3.9% (1129 of 28 789) of HBsAg-positive persons were HIV positive. The probable route of HIV infection was heterosexual exposure for 95.3% of female patients and 32.3% of male patients, with 61.5% of male patients reporting sex between men. Among African-born coinfected persons, 84% probably acquired HIV there. Predictors of HIV positivity included older age [adjusted odds ratio (aOR) 1.1] and being of black ethnicity (aOR 15.5 for males; aOR 16.4 for females) or being male and of white ethnicity (aOR 8.2) compared with being female and of white ethnicity. HIV coinfection was more likely when HBV was diagnosed in sexual health (aOR 55.0), specialist liver (aOR 6.7), emergency department (aOR 5.3) and renal services (aOR 2.8) compared with general practice. Most (60.4%; 682 of 1129) coinfected persons were diagnosed with HIV infection > 6 months before HBV diagnosis. CONCLUSIONS: Persons testing positive for HBsAg had a low HIV infection rate and fell largely into two groups: those of black ethnicity with probable Africa-acquired infections and white men who have sex with men (MSM) with probable UK-acquired infections. Findings reinforce existing recommendations to sustain and improve both HBV testing of migrants from HBV-prevalent countries and vaccination among HIV-positive MSM. Findings also support blood-borne virus testing in sexual health services and emergency departments.


Assuntos
Infecções por HIV/epidemiologia , Hepatite B/complicações , Adolescente , Adulto , Idoso , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
16.
Epidemiol Infect ; 147: e145, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30869036

RESUMO

SUMMARY: In this paper we build on work investigating the feasibility of human immunodeficiency virus (HIV) testing in emergency departments (EDs), estimating the prevalence of hepatitis B, C and HIV infections among persons attending two inner-London EDs, identifying factors associated with testing positive in an ED. We also undertook molecular characterisation to look at the diversity of the viruses circulating in these individuals, and the presence of clinically significant mutations which impact on treatment and control.Blood-borne virus (BBV) testing in non-traditional settings is feasible, with emergency departments (ED) potentially effective at reaching vulnerable and underserved populations. We investigated the feasibility of BBV testing within two inner-London EDs. Residual samples from biochemistry for adults (⩾18 years) attending The Royal Free London Hospital (RFLH) or the University College London Hospital (UCLH) ED between January and June 2015 were tested for human immunodeficiency virus (HIV)Ag/Ab, anti-hepatitis C (HCV) and HBsAg. PCR and sequence analysis were conducted on reactive samples. Sero-prevalence among persons attending RFH and UCLH with residual samples (1287 and 1546), respectively, were 1.1% and 1.0% for HBsAg, 1.6% and 2.3% for anti-HCV, 0.9% and 1.6% for HCV RNA, and 1.3% and 2.2% for HIV. For RFH, HBsAg positivity was more likely among persons of black vs. white ethnicity (odds ratio 9.08; 95% confidence interval 2.72-30), with anti-HCV positivity less likely among females (0.15, 95% CI 0.04-0.50). For UCLH, HBsAg positivity was more likely among non-white ethnicity (13.34, 95% CI 2.20-80.86 (Asian); 8.03, 95% CI 1.12-57.61 (black); and 8.11, 95% CI 1.13-58.18 (other/mixed)). Anti-HCV positivity was more likely among 36-55 year olds vs. ⩾56 years (7.69, 95% CI 2.24-26.41), and less likely among females (0.24, 95% CI 0.09-0.65). Persons positive for HIV-markers were more likely to be of black vs. white ethnicity (4.51, 95% CI 1.63-12.45), and less likely to have one ED attendance (0.39, 95% CI 0.17-0.88), or female (0.12, 95% CI 0.04-0.42). These results indicate that BBV-testing in EDs is feasible, providing a basis for further studies to explore provider and patient acceptability, referral into care and cost-effectiveness.


Assuntos
Anticorpos Anti-HIV/sangue , Antígenos HIV/sangue , Infecções por HIV/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Feminino , Genótipo , HIV/classificação , HIV/genética , HIV/imunologia , Hepacivirus/classificação , Hepacivirus/genética , Hepacivirus/imunologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hospitais , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
17.
J Appl Microbiol ; 126(6): 1742-1750, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30817048

RESUMO

AIMS: Hot springs have always drawn attention due to their unique chemical richness and the presence of different microbial communities. The use of hot spring bacteria in concrete technology is our primary focus; isolation of an alkaliphilic bacterium from the Bakreshwar hot springs having longer survival and better efficacy towards cementitious environment was the basis of our study's design. METHODS AND RESULTS: A novel facultative anaerobic and highly alkaliphilic bacterial strain (BKH4; GenBank accession no. KX622782) belonging to the family 'Bacillaceae' and homologous (99%) with Lysinibacillus fusiformis was isolated from Bakreshwar hot springs. The isolated coccoid-type Gram-positive bacterium grows well in a defined semi-synthetic medium (pH 12·0 and 65°C). This bacterium survives for more than a month and shows better efficacy in enhancing compressive strengths (>50%), ultrasonic pulse velocity (>25%) and durability of the cementitious mortar when incorporated at a concentration of 104  cells per ml of water used. CONCLUSION: The novel bacterium BKH4 is more effective for the enhancement of the bioconcrete properties. SIGNIFICANCE AND IMPACT OF THE STUDY: BKH4 bacterium will add a new dimension to future concrete technology for its usefulness in strength enhancement and durability due to its alkaliphilic nature and longer survival within a cementitious environment.


Assuntos
Álcalis/metabolismo , Bacillaceae/fisiologia , Biotecnologia , Materiais de Construção/microbiologia , Fontes Termais/microbiologia , Bacillaceae/genética , Bacillaceae/metabolismo , Força Compressiva , DNA Bacteriano/genética , Temperatura Alta , Concentração de Íons de Hidrogênio , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
Euro Surveill ; 24(41)2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31615597

RESUMO

IntroductionLiver transplantation is an important measure of burden from hepatitis C virus (HCV)-associated liver disease.AimsTo describe transplant rates and survival in individuals with HCV infection from 2008 to 2017 in England through data linkage.MethodsThis is a retrospective observational cohort study. Laboratory reports of HCV infection were linked to the Liver Transplant Registry for individuals aged 15 years and over, first diagnosed between 1998 and 2017. We estimated age-sex standardised incidence rates and used Poisson regression to investigate predictors of liver transplantation and test for a change in incidence after introduction of direct-acting antivirals (DAAs) in 2014. Kaplan-Meier survival analysis was used to calculate post-transplant survival rates.ResultsOf 124,238 individuals diagnosed with HCV infection, 1,480 were registered and 1,217 received a liver transplant. Of individuals registered, 1,395 had post-HCV cirrhosis and 636 had hepatocellular carcinoma (618 also had post-HCV cirrhosis). Median time from HCV diagnosis to transplant was 3.4 years (interquartile range: 1.3-6.8 years). Liver transplant rates were lower 2014-17 compared with 2011-13 (incidence rate ratio: 0.64; 95% confidence interval: 0.55-0.76). Survival rates were 93.4%, 79.9% and 67.9% at 1, 5 and 10 years, respectively. Data linkage showed minimal under-reporting of HCV in the transplant registry.ConclusionIn the post-DAA era, liver transplant rates have fallen in individuals with HCV infection, showing early impact of HCV treatment scale-up; but the short time from HCV diagnosis to liver transplant suggests late diagnosis is a problem.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/cirurgia , Hepatite C/terapia , Transplante de Fígado/estatística & dados numéricos , Transplantados/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inglaterra/epidemiologia , Feminino , Hepatite C/diagnóstico , Hepatite C/mortalidade , Hepatite C Crônica/mortalidade , Hepatite C Crônica/virologia , Humanos , Incidência , Armazenamento e Recuperação da Informação , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Adulto Jovem
19.
Public Health ; 168: 150-156, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30442468

RESUMO

OBJECTIVES: A routine review of hepatitis A travel vaccination recommendations was brought forward in June 2017 due to hepatitis A vaccine shortages and a concurrent outbreak in men who have sex with men (MSM). There were three objectives: first, to document the review process for changing the recommendations for the UK travellers in June 2017. Second, to study the impact of these changes on prescribing in general practice in 2017 compared with the previous 5 years. Third, to study any changes in hepatitis A notifications in June-October 2017 compared with the previous 5 years. STUDY DESIGN: This is an observational study. METHODS: Travel vaccination recommendations for countries with either low-risk (<20%) or high-risk (>90%) status according to child hepatitis A seroprevalence were not changed. A total of 67 intermediate-risk countries with existing recommendations for most travellers and with new data on rural sanitation levels were shortlisted for the analysis. Data on child hepatitis A seroprevalence, country income status, access to sanitation in rural areas and traveller volumes were obtained. Information about the vaccine supply was obtained from Public Health England. Changes to the existing classification were made through expert consensus, based on countries' hepatitis A seroprevalence, sanitation levels, level of income, volume of travel and hepatitis A traveller cases. Data on the number of combined and monovalent hepatitis A-containing vaccines prescribed in England, 2012-2017, were obtained from the National Health Service Business Service Authorities. The number of monthly prescriptions for January-September 2017 was compared with the mean number of prescriptions for the same month in the previous 5 years (t-test, α = 5%, df = 4). The number of hepatitis A cases notified in June-October 2017 not related to the MSM outbreak was compared with the number of notifications in the same months in previous years. RESULTS: A total of 36 countries were downgraded based on good access (80+% of population) to sanitation in rural areas and the intermediate-risk status in terms of child hepatitis A seroprevalence. For these countries, vaccination would only be recommended to travellers staying long term, visiting friends and relatives or staying in areas without good sanitation. There was a significant decline in hepatitis A vaccine prescriptions in June-September 2017, and there was no increase in the number of notifications. CONCLUSIONS: Hepatitis A vaccination recommendations for travel were revised in 2017 following a systematic approach to maintain continuity of supply after a hepatitis A vaccine shortage and increased hepatitis A vaccine demand related to a large outbreak. Improved access to good sanitation in rural areas and low seroprevalence estimates among children have led to 36 countries to no longer require vaccination for most travellers. These changes do not seem to have impacted on hepatitis A notifications in England, although further research will be needed to quantify the impact more precisely.


Assuntos
Política de Saúde , Vacinas contra Hepatite A/administração & dosagem , Vacinas contra Hepatite A/provisão & distribuição , Hepatite A/prevenção & controle , Viagem , Surtos de Doenças/prevenção & controle , Hepatite A/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Guias de Prática Clínica como Assunto , Reino Unido/epidemiologia
20.
Acta Orthop Belg ; 85(4): 525-534, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32374244

RESUMO

Unstable trochanteric fractures and fractures with reverse obliquity pose difficulty in fixation. In recent years, intramedullary nails, for the treatment of comminuted and unstable intertrochanteric hip fractures, are becoming more popular relative to conventional, sliding hip screws. The purpose of our study was to evaluate the result of Trochanteric femoral nailing in comminuted, unstable Trochanteric femur fracture in terms of anatomical restoration and functional outcome. It is a prospective and without control study. Trochanteric femoral nailing has been done in comminuted unstable inter-trochanteric fracture femur (AO A2.2 to A3.3) of 25 patients and they are followed up postoperatively for at least 12 months. Pre-operative and post-operative clinical and radio-logical parameters are compared accordingly. Union in all cases. Overall complication rate 12% including some implant related complications. Functional outcome on Harris Hip Score is comparable with standard literature. For treatment of intertrochanteric hip fractures, particularly with comminuted fracture fragments, intramedullary devices offer beneficial features, such as closed insertion, a shorter lever arm, and controlled telescoping of the head-neck fragment. Insertion of the nail through the tip of the greater trochanter requires less dissection and may lead to less blood loss and fewer wound complications, as well as earlier postoperative mobility. Further biomechanical and clinical studies are necessary to validate the efficacy of the trochanteric femoral nail. Level of Evidence : Level III therapeutic study.


Assuntos
Pinos Ortopédicos , Fixação Intramedular de Fraturas/métodos , Fraturas Cominutivas/cirurgia , Fraturas do Quadril/cirurgia , Adulto , Idoso , Avaliação da Deficiência , Feminino , Fraturas Cominutivas/diagnóstico por imagem , Fraturas do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia
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