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1.
Phys Chem Chem Phys ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967480

RESUMO

Quantum spin liquids (QSLs) have become prominent materials of interest in the pursuit of fault-tolerant materials for quantum computing applications. This is due to the fact that these materials are theorized to host an interesting variety of quantum phenomena such as quasi-particles that may behave as anyons as a result of the high entangled nature of the spin states within the systems. Computing the electronic and magnetic properties of these materials is necessary in order to understand the underlying interactions of the materials. In this paper, the structural, electronic, and magnetic properties including lattice parameters, bandgap, Heisenberg coupling constants, and Curie temperatures for α-RuCl3, a promising candidate for the Kitaev QSL model, are computed using periodic density functional theory. Furthermore, various parameters of the calculations (i.e. functional choice, basis set, k-point density, and Hubbard correction) are varied in order to determine what effect, if any, the computational setup has on the computed properties. The results of this study indicate that PBE functional with Hubbard corrections of 1.5-2.5 eV with a k-point density of 3.0 points per Å-1 appear to be the best parameters to compute Heisenberg coupling constants for α-RuCl3. These parameters with the addition of spin orbit coupling works well for computing Curie temperatures for α-RuCl3. Distinct differences are noted in the computations of the bulk structure vs. monolayer structures, indicating that interactions between the layers play a role in the material properties and changes to the inter-layer spacing may result in interesting and unique magnetic properties that require further investigation.

2.
J Environ Manage ; 351: 119872, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157579

RESUMO

Controlled release of active ingredients are important for drug delivery and more recently environmental applications including modulated dosing of chemical and biological controls. This study demonstrates the importance of investigating various material science factors that can influence the diffusion rates of alginate beads to improve and tune their performance for marine environmental applications. This investigation aimed to design a rational workflow to aid in leveraging alginate bead use as a carrier matrix for releasing a specific active agent into water. Experiments were conducted to focus on the narrow a large list of relevant material formulation parameters, which included chitosan molecular weight, chitosan concentration, calcium concentration, drop height, and bead size. Once the most relevant material preparation methods were screened, a more robust statistic Design of Experiments approach was performed and results determined the important (and unimportant) factors for increasing dye release kinetics in marine water. The process was further streamlined by narrowing the critical experimental factors to a three-level based on the prior analysis: chitosan MW, chitosan concentration, and bead size. Analysis of the collected data indicated that while chitosan MW had a negligible impact (Fstatistic = 0.22), bead size (Fstatistic = 60.33) significantly influenced the diffusion rates based on surface area. However, chitosan MW had minor effects where lower chitosan MW enabled higher product release rates. This case investigation was a novel application of the design of experiment approach towards environmental applications to understand differences in release rates to marine waters for the first time and the workflow provided also serve as the basis for researchers to optimize other environmental applications requiring optimization when it is unknown how a large number of formulation variables will impact performance in different environmental scenarios.


Assuntos
Quitosana , Quitosana/química , Alginatos/química , Cálcio , Água , Ácidos Hexurônicos/química , Ácido Glucurônico/química
3.
medRxiv ; 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35262086

RESUMO

Background: Using classical and genomic epidemiology, we tracked the COVID-19 pandemic in Kenya over 23 months to determine the impact of SARS-CoV-2 variants on its progression. Methods: SARS-CoV-2 surveillance and testing data were obtained from the Kenya Ministry of Health, collected daily from 306 health facilities. COVID-19-associated fatality data were also obtained from these health facilities and communities. Whole SARS-CoV-2 genome sequencing were carried out on 1241 specimens. Results: Over the pandemic duration (March 2020 - January 2022) Kenya experienced five waves characterized by attack rates (AR) of between 65.4 and 137.6 per 100,000 persons, and intra-wave case fatality ratios (CFR) averaging 3.5%, two-fold higher than the national average COVID-19 associated CFR. The first two waves that occurred before emergence of global variants of concerns (VoC) had lower AR (65.4 and 118.2 per 100,000). Waves 3, 4, and 5 that occurred during the second year were each dominated by multiple introductions each, of Alpha (74.9% genomes), Delta (98.7%), and Omicron (87.8%) VoCs, respectively. During this phase, government-imposed restrictions failed to alleviate pandemic progression, resulting in higher attack rates spread across the country. Conclusions: The emergence of Alpha, Delta, and Omicron variants was a turning point that resulted in widespread and higher SARS-CoV-2 infections across the country.

4.
Microbiol Resour Announc ; 11(4): e0124121, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35343778

RESUMO

An Escherichia coli strain (sequence type 636) was isolated from an adult residing in an urban informal settlement in Nairobi, Kenya, and was sequenced using the Illumina MiSeq platform. The draft genome was 5,075,726 bp, with a Col(BS512) plasmid plus aph(6)-Id, blaTEM-1B, and dfrA7 genes, which encode kanamycin, ampicillin, and trimethoprim resistance proteins, respectively.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22271467

RESUMO

BackgroundUsing classical and genomic epidemiology, we tracked the COVID-19 pandemic in Kenya over 23 months to determine the impact of SARS-CoV-2 variants on its progression. MethodsSARS-CoV-2 surveillance and testing data were obtained from the Kenya Ministry of Health, collected daily from 306 health facilities. COVID-19-associated fatality data were also obtained from these health facilities and communities. Whole SARS-CoV-2 genome sequencing were carried out on 1241 specimens. ResultsOver the pandemic duration (March 2020 - January 2022) Kenya experienced five waves characterized by attack rates (AR) of between 65.4 and 137.6 per 100,000 persons, and intra-wave case fatality ratios (CFR) averaging 3.5%, two-fold higher than the national average COVID-19 associated CFR. The first two waves that occurred before emergence of global variants of concerns (VoC) had lower AR (65.4 and 118.2 per 100,000). Waves 3, 4, and 5 that occurred during the second year were each dominated by multiple introductions each, of Alpha (74.9% genomes), Delta (98.7%), and Omicron (87.8%) VoCs, respectively. During this phase, government-imposed restrictions failed to alleviate pandemic progression, resulting in higher attack rates spread across the country. ConclusionsThe emergence of Alpha, Delta, and Omicron variants was a turning point that resulted in widespread and higher SARS-CoV-2 infections across the country.

6.
Crit Rev Anal Chem ; 52(6): 1244-1258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33430614

RESUMO

Harmful algal blooms (HABs) negatively impact numerous natural waterways worldwide and have significant socioeconomic and health-related ramifications for local populations. In order to better detect, characterize, and mitigate bloom events, novel field deployable analytical technologies capable of quantifying common HAB toxins (e.g., microcystins) are of paramount importance. Toward this end, molecularly imprinted polymer (MIP) transducing elements used in conjunction with sensitive analytical techniques may be a useful tool for microcystin detection and quantification. Indeed, several efforts have been undertaken in the last decade (2010-2020) to combine the selectivity provided by MIPs with various analytical methods, many of which are adaptable for in-field analysis. This review presents a summary of the current state of microcystins detection methods incorporating MIPs with a focus on potentiometry, photoelectrochemistry, liquid chromatography, quartz crystal microbalance, competitive ELISA, interferometry, and immunochromatography. Furthermore, a perspective detailing trends and observations from the current body of literature is provided to guide future MIP-based microcystin and other HAB toxin detection efforts with a specific focus on deployable analytical platforms.


Assuntos
Microcistinas , Polímeros Molecularmente Impressos , Cromatografia Líquida , Proliferação Nociva de Algas , Microcistinas/análise , Microcistinas/química
7.
Viruses ; 13(10)2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34696386

RESUMO

The spatiotemporal patterns of spread of influenza A(H1N1)pdm09 viruses on a countrywide scale are unclear in many tropical/subtropical regions mainly because spatiotemporally representative sequence data are lacking. We isolated, sequenced, and analyzed 383 A(H1N1)pdm09 viral genomes from hospitalized patients between 2009 and 2018 from seven locations across Kenya. Using these genomes and contemporaneously sampled global sequences, we characterized the spread of the virus in Kenya over several seasons using phylodynamic methods. The transmission dynamics of A(H1N1)pdm09 virus in Kenya were characterized by (i) multiple virus introductions into Kenya over the study period, although only a few of those introductions instigated local seasonal epidemics that then established local transmission clusters, (ii) persistence of transmission clusters over several epidemic seasons across the country, (iii) seasonal fluctuations in effective reproduction number (Re) associated with lower number of infections and seasonal fluctuations in relative genetic diversity after an initial rapid increase during the early pandemic phase, which broadly corresponded to epidemic peaks in the northern and southern hemispheres, (iv) high virus genetic diversity with greater frequency of seasonal fluctuations in 2009-2011 and 2018 and low virus genetic diversity with relatively weaker seasonal fluctuations in 2012-2017, and (v) virus spread across Kenya. Considerable influenza virus diversity circulated within Kenya, including persistent viral lineages that were unique to the country, which may have been capable of dissemination to other continents through a globally migrating virus population. Further knowledge of the viral lineages that circulate within understudied low-to-middle-income tropical and subtropical regions is required to understand the full diversity and global ecology of influenza viruses in humans and to inform vaccination strategies within these regions.


Assuntos
Epidemias , Genoma Viral , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/epidemiologia , Variação Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Quênia/epidemiologia , Filogenia , RNA Viral/genética , Estações do Ano
8.
BMC Nutr ; 7(1): 46, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34321101

RESUMO

BACKGROUND: Annually, undernutrition contributes globally to 45% (3.1 million) of preventable deaths in children under 5. Effect following undernutrition i.e. physical growth & cognitive development etc. can be prevented during the first 1000 days also called window of opportunity. There is substantial evidence of positive nutrition outcomes resulting from integrating nutrition-specific interventions into nutrition specific program. However, there is paucity of knowledge on establishing and sustaining effective integration of nutrition intervention in fragile context. The objective of this review is to map and review the integration of nutrition-specific intervention to nutrition sensitive program and its impacts on nutrition outcomes. METHODS: In the study, we systematically searched the literature on integrated nutrition intervention into multi-sectoral programme in PUBMED, Google's Scholar, the Cochrane Library, World Health Organisation (WHO), United Nations Children's Fund (UNICEF), World Bank and trial registers from their inception until Oct 30, 2020 for up-to-date published and grey resources. We screened records, extracted data, and assessed risk of bias in duplicates. This study is registered with PROSPERO (CRD42020209730). RESULT: Forty-four studies were included in this review, outlining the integration of nutrition-specific interventions among children 0-59 months with various existing programme. Most common integration platform in the study included integrated community case management and Integrated Management of Childhood Illness, Child Health Days, immunization, early child development, and cash transfers. Limited quantitative data were suggestive of some positive impact on nutrition and non-nutrition outcomes with a number of model of integration which varies according to the context and demands of the particular setting in which integration occurs. CONCLUSION: Overall, existing evidence for nutrition sensitive and specific interventions is not robust and remains limited. It's worthwhile to note, for future studies/interventions should be based on the context key criteria like relevance, political support, effectiveness, feasibility, expected contribution to health system strengthening, local capacities, ease of integration and targeting for sustainability, cost effectiveness and financial availability.

9.
ACS Omega ; 6(8): 5158-5165, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33681557

RESUMO

Trace analysis of heavy metals in complex, environmentally relevant matrices remains a significant challenge for electrochemical sensors employing stripping voltammetry-based detection schemes. We present an alternative method capable of selectively preconcentrating Cu2+ ions at the electrode surface using chelating polymer-wrapped multiwalled carbon nanotubes (MWCNTs). An electrochemical sensor consisting of poly-4-vinyl pyridine (P4VP)-wrapped MWCNTs anchored to a poly(ethylene terephthalate) (PET)-modified gold electrode (r = 1.5 mm) was designed, produced, and evaluated. The P4VP is shown to form a strong association with Cu2+ ions, permitting preconcentration adjacent to the electrode surface for interrogation via cyclic voltammetry. The sensor exhibited a detection limit of 0.5 ppm with a linear range of 1.1-13.8 ppm (16.6-216 µM) and a relative standard deviation (RSD) of 4.9% at the Environmental Protection Agency (EPA) limit of 1.3 ppm. Evaluation in tap water, lake water, ocean water, and deionized water rendered similar results, highlighting the generalizability of the presented preconcentration strategy. The advantages of electrochemical analysis paired with polymeric chelation represent an effective platform for the design and deployment of heavy metal sensors for continuous monitoring of natural waters.

10.
Br J Oral Maxillofac Surg ; 59(4): 433-438, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33715891

RESUMO

Cervicofacial infection (CFI) is a common presentation to the Oral and Maxillofacial (OMFS) department and accounts for significant emergency activity. The current study aims to understand the aetiology, management, and clinical features of patients hospitalised with CFI. Our study included all patients admitted for management of CFI from May to October 2017 at 25 OMFS units across 17 UK regions. Data were collected prospectively and included age, comorbidities, prior treatment received, markers of sepsis, and presenting clinical features. One thousand and two (1002) admissions were recorded; 546 (54.5%) were male. Median (range) age was 34 (1-94) years. The most common presenting complaints were trismus (46%) and dysphagia (27%). Airway compromise was present in 1.7% of cases. Odontogenic infection accounted for 822/1002 (82%) admissions. Of those with an infection of odontogenic origin, 453/822 (55.1%) had received previous treatment. Two-thirds of those who had received treatment were managed by antibiotics alone (300/453, 66.2%). Patients met criteria for sepsis in 437/1002 (43.6%) of CFI, and in 374/822 (45.5%) of odontogenic infections. This is the largest study worldwide of patients requiring inpatient management for CFI. Infection due to odontogenic origin is the most frequent reason for admission and nearly half do not seek treatment before presentation. Patients with CFI often present late in their disease and frequently meet criteria for sepsis, requiring timely and aggressive treatment to ensure optimum outcomes. Trismus is an emerging dominant feature with all the implications related to the anaesthetic management of these patients. Knowledge of these factors has implications for the referrer, triage, the emergency department, the anaesthetic team, and members of the OMFS team.


Assuntos
Serviço Hospitalar de Emergência , Sepse , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/epidemiologia , Triagem
11.
Aerosp Med Hum Perform ; 91(11): 886-891, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33334409

RESUMO

INTRODUCTION: We assessed determinants of serum hs-CRP level in pilots and air traffic controllers (ATCs) and its impact on their atherosclerotic cardiovascular disease (ASCVD) risk.METHODS: We obtained serum hs-CRP measurements, evaluated traditional cardiovascular risk factors and assessed global ASCVD risk based on 2018 ESH/ESC guidelines. Elevated hs-CRP was hs-CRP values > 3 mg L1. Determinants of elevated hs-CRP were assessed using stepwise logistic regression analysis. We used the net reclassification method to evaluate the impact of hs-CRP levels on global ASCVD risk.RESULTS: Of the 335 subjects (mean age 45.4 11.6 yr, 70% pilots, 99% men, 37% Caucasians), 127 individuals (39.5%) presented with elevated hs-CRP levels. Compared to those with normal hs-CRP, individuals with elevated hs-CRP were older with faster heart rate and higher blood pressure, BMI, and P wave amplitude. The proportion of individuals with elevated hs-CRP was greater among those with smoking habits, physical inactivity, MetS, tachycardia, altered P wave axis, LVH, and HT-TOD. Aging (aOR 2.15 [1.676.98]), hypertension (aOR 3.88 [2.296.58]), type 2 diabetes (aOR 6.71 [1.7710.49]), tachycardia (aOR 2.03 [1.914.53]), and LVH (aOR 2.13 [1.647.11]) were the main factors associated with elevated hs-CRP levels. Low, moderate, high, and very high risk were observed in 24 (15%), 68 (41%), 62 (37%), and 12 (7%) subjects, respectively. Including hs-CRP resulted in the net reclassification of 25% of subjects, mostly from moderate to high risk.CONCLUSION: The integration of hs-CRP improved the estimation of global ASCVD risk stratification. However, a survey with a comprehensive population assessing the cost/benefit impact of such a referral is needed.Buila NB, Ntambwe ML, Mupepe DM, Lubenga YN, Bantu J-MB, Mvunzi TS, Kabanda GK, Lepira FB, Kayembe PK, Ditu SM, MBuyamba-Kabangu J-R. The impact of hs-CRP on cardiovascular risk stratification in pilots and air traffic controllers. Aerosp Med Hum Perform. 2020; 91(11):886891.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Biomarcadores , Proteína C-Reativa/análise , Doenças Cardiovasculares/epidemiologia , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
12.
Eur Heart J Suppl ; 22(Suppl H): H50-H52, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32884469

RESUMO

Hypertension (HT) is the largest contributor to cardiovascular disease mortality and is characterized by high prevalence and low awareness, treatment, and control rates in sub-Saharan Africa. May Measurement Month (MMM) is an international campaign intended to increase awareness of high blood pressure (BP) among the population and advocate for its importance to the health authorities. This study aimed to increase awareness of raised BP in a country where its nationwide prevalence is yet unestablished. Investigators trained and tested how to use the campaign materials, collected participants' demographic data, lifestyle habits, and obtained from each one three BP measurements. Hypertension was defined as a BP ≥140/90 mmHg, or use of antihypertensive medication. Of the 18 719 screened (mean age 41 years; 61.4% men), 26.1% were found to be hypertensive of whom 46.3% were aware of their condition and 29.6% were taking antihypertensive medication. The control rate of HT was 43.0% in those on medication and 12.7% among all hypertensive respondents. Comorbidities found were-diabetes (3.3%), overweight/obesity (35.5%); and a previous stroke and a previous myocardial infarction were reported by 1.2% and 2.0%, respectively. Imputed age- and sex-standardized BP was higher in treated hypertensive individuals (135/85 mmHg) than those not treated (124/78 mmHg). Based on linear regression models adjusted for age and sex (and an interaction) and antihypertensive medication, stroke survivors, those who drank once or more per week (vs. never/rarely), and overweight/obese participants were associated with higher BP. MMM18 results in the Democratic Republic of the Congo corroborated the high prevalence of HT in Kinshasa screenees with low rates of treatment and control. Extension of the MMM campaign to other parts of the country is advisable.

13.
Br J Oral Maxillofac Surg ; 57(3): 196-206, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30770139

RESUMO

The role of corticosteroids in the management of cervicofacial infections continues to cause controversy. Systemic anti-inflammatory and immunomodulatory effects that reduce swelling and improve symptoms in the head and neck may make these agents an effective addition to the antibiotics used and to surgical management, although this same effect may dull the physiological response to infection, and allow infections to progress. We have systematically reviewed the evidence for the use of corticosteroids in common cervicofacial infections following the PRISMA guidelines. MeSH terms included "head", "neck", "infection", and "glucocorticoid". In total, 31 papers were identified. Eight reported the use of corticosteroids for peritonsillar abscess (PTA), 10 for pharyngitis, four for deep neck space infection (DNSI), four for periorbital cellulitis, and five for supraglottitis. Whilst there is an established evidence base for their use in the treatment of PTA and pharyngitis, other indications need further study, and we highlight the potential pitfalls. The evidence suggests that the use of adjunctive, short-term, high-dose corticosteroids in cervicofacial infections may be safe and effective.


Assuntos
Corticosteroides/uso terapêutico , Infecções/tratamento farmacológico , Abscesso Peritonsilar , Faringite , Antibacterianos , Cabeça , Humanos , Pescoço
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 596-599, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30440467

RESUMO

In this paper, we present a new diffeomorphic registration algorithm for the registration of 3D models to 3D points. A biventricular template is iteratively fitted to the data by a series of implicitly constrained diffeomorphic linear least squares fits with decreasing regularization weights before performing an explicitly constrained diffeomorphic fit. The algorithm has been tested on a set of manual contours from 20 patients with a variety of congenital heart disease. Registration accuracy was assessed by calculating the mean point-to-point distance and the Dice overlap metric. Results showed that the method was able to accurately fit the biventricular model to 3D points and that the deformable model was able to fit all the pathologies while being diffeomorphic. The algorithm took approximately 5 minutes to fit each case, with an average of 52,580 points per case.


Assuntos
Algoritmos , Cardiopatias/congênito , Cardiopatias/diagnóstico , Modelos Cardiovasculares , Humanos
15.
J Am Chem Soc ; 140(31): 9819-9822, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30048128

RESUMO

We report the crystallography, emission spectra, femtosecond pump-probe spectroscopy, and density functional theory computations for a series of ruthenium complexes that comprise a new class of chelating triphenylphosphine based ligands with an appended sulfoxide moiety. These ligands differ only in the presence of the para-substitutent (e.g., H, OCH3, CF3). The results show a dramatic range in photoisomerization reactivity that is ascribed to differences in the electron density of the phosphine ligand donated to the ruthenium and the nature of the excited state.

16.
Inorg Chem ; 57(9): 5701-5706, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29663799

RESUMO

Ruthenium sulfoxide complexes undergo thermally reversible linkage isomerization of sulfoxide ligands from S- to O-bound in response to light. Here, we report photoisomerization action spectra for a ruthenium bis-sulfoxide molecular photoswitch, [Ru(bpy)2(bpSO)]2+, providing the first direct evidence for photoisomerization of a transition metal complex in the gas phase. The linkage isomers are separated and isolated in a tandem drift tube ion mobility spectrometer and exposed to tunable laser radiation provoking photoisomerization. Direct switching of the S,S-isomer to the O,O-isomer following absorption of a single photon is the predominant isomerization pathway in the gas phase, unlike in solution, where stepwise isomerization is observed with each sulfoxide ligand switching in turn. The change in isomerization dynamics is attributed to rapid vibrational quenching that suppresses isomerization in solution. Supporting electronic structure calculations predict the wavelengths and intensities of the peaks in the photoisomerization action spectra of the S,S- and S,O-isomers, indicating that they correspond to metal-to-ligand charge transfer (MLCT) and ligand-centered ππ* transitions.

17.
Br J Oral Maxillofac Surg ; 56(4): 278-282, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29523362

RESUMO

We reviewed longitudinal recruitment data to assess recruitment into head and neck cancer trials, and to identify factors that could influence this and affect their acceptability to patients. We retrieved data from the prospective computerised database (2009-2016) to measure acceptability to patients using the recruitment:screening ratio, and compared observational with interventional studies, single specialty (or site) with multispecialty (or site) studies, and "step-up" randomisation with "non-inferiority" randomisation designs. A total of 1283 patients were screened and 583 recruited. The recruitment:screening ratio for all National Institute for Health Research (NIHR) portfolio studies combined was 0.47 (486/1133). Studies that involved treatment by several specialties or at several sites had a significantly adverse impact on acceptability (p=0.01). Recruitment into non-inferiority randomised controlled studies was lower than that into step-up randomised studies (p=0.06). The complexity of a study's design did not compromise recruitment. Treatment across several specialties or several sites and perceived non-inferiority designs, reduced the acceptability of some trials.


Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Aceitação pelo Paciente de Cuidados de Saúde , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Humanos , Estudos Observacionais como Assunto/métodos , Estudos Observacionais como Assunto/normas , Estudos Observacionais como Assunto/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Preferência do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Pesquisadores/estatística & dados numéricos
18.
Int J Cardiovasc Imaging ; 34(3): 407-417, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28856524

RESUMO

Although more patients with congenital heart disease (CHD) are now living longer due to better surgical interventions, they require regular imaging to monitor cardiac performance. There is a need for robust clinical tools which can accurately assess cardiac function of both the left and right ventricles in these patients. We have developed methods to rapidly quantify 4D (3D + time) biventricular function from standard cardiac MRI examinations. A finite element model was interactively customized to patient images using guide-point modelling. Computational efficiency and ability to model large deformations was improved by predicting cardiac motion for the left ventricle and epicardium with a polar model. In addition, large deformations through the cycle were more accurately modeled using a Cartesian deformation penalty term. The model was fitted to user-defined guide points and image feature tracking displacements throughout the cardiac cycle. We tested the methods in 60 cases comprising a variety of congenital heart diseases and showed good correlation with the gold standard manual analysis, with acceptable inter-observer error. The algorithm was considerably faster than standard analysis and shows promise as a clinical tool for patients with CHD.


Assuntos
Cardiopatias Congênitas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Função Ventricular Esquerda , Função Ventricular Direita , Algoritmos , Análise de Elementos Finitos , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Humanos , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Resultado do Tratamento
19.
Genetics ; 208(2): 763-777, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29187508

RESUMO

Humans have colonized the planet through a series of range expansions, which deeply impacted genetic diversity in newly settled areas and potentially increased the frequency of deleterious mutations on expanding wave fronts. To test this prediction, we studied the genomic diversity of French Canadians who colonized Quebec in the 17th century. We used historical information and records from ∼4000 ascending genealogies to select individuals whose ancestors lived mostly on the colonizing wave front and individuals whose ancestors remained in the core of the settlement. Comparison of exomic diversity reveals that: (i) both new and low-frequency variants are significantly more deleterious in front than in core individuals, (ii) equally deleterious mutations are at higher frequencies in front individuals, and (iii) front individuals are two times more likely to be homozygous for rare very deleterious mutations present in Europeans. These differences have emerged in the past six to nine generations and cannot be explained by differential inbreeding, but are consistent with relaxed selection mainly due to higher rates of genetic drift on the wave front. Demographic inference and modeling of the evolution of rare variants suggest lower effective size on the front, and lead to an estimation of selection coefficients that increase with conservation scores. Even though range expansions have had a relatively limited impact on the overall fitness of French Canadians, they could explain the higher prevalence of recessive genetic diseases in recently settled regions of Quebec.


Assuntos
Genética Populacional , Modelos Genéticos , Seleção Genética , Algoritmos , Alelos , Evolução Biológica , Simulação por Computador , Demografia , Evolução Molecular , Frequência do Gene , Ontologia Genética , Aptidão Genética , Variação Genética , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Quebeque
20.
Br J Oral Maxillofac Surg ; 55(9): 940-945, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29033149

RESUMO

Cervicofacial infections are common emergency presentations to maxillofacial departments in the UK, there is no consensus about their management and, in particular, the role of corticosteroids is not clear. Our aim was to find out the current practice of UK maxillofacial surgeons in managing these infections using a multicentre questionnaire study. The questionnaire was designed, piloted, and revised before distribution, and questions were asked to assess preoperative, operative, and postoperative management. It was distributed to maxillofacial surgeons throughout the UK through the Maxillofacial Research Trainee Collaborative (MTReC) network, and at the 2016 British Association of Oral and Maxillofacial Surgeons (BAOMS) Junior Trainees Group conference. A total of 350 questionnaires were distributed to 17 maxillofacial units. Eighty-six questionnaires were distributed at the BAOMS Junior Trainee conference. An overall response rate of 92% (n=324) was achieved. The results showed that there were important differences in reported practice between and within maxillofacial units in the UK in managing these infections. The antibiotic regimens and use of steroids varied widely. Twenty-three per cent of respondents had to wait over 24hours for access to emergency theatres. However, these results provide no hard evidence for or against the use of corticosteroids in cervicofacial infections.


Assuntos
Infecção Focal Dentária/terapia , Padrões de Prática Médica/estatística & dados numéricos , Corticosteroides/uso terapêutico , Antibacterianos/uso terapêutico , Humanos , Procedimentos Cirúrgicos Bucais , Sociedades Médicas , Inquéritos e Questionários , Reino Unido
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