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1.
Cell ; 172(3): 491-499.e15, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29358049

RESUMO

Non-coding "ultraconserved" regions containing hundreds of consecutive bases of perfect sequence conservation across mammalian genomes can function as distant-acting enhancers. However, initial deletion studies in mice revealed that loss of such extraordinarily constrained sequences had no immediate impact on viability. Here, we show that ultraconserved enhancers are required for normal development. Focusing on some of the longest ultraconserved sites genome wide, located near the essential neuronal transcription factor Arx, we used genome editing to create an expanded series of knockout mice lacking individual or combinations of ultraconserved enhancers. Mice with single or pairwise deletions of ultraconserved enhancers were viable and fertile but in nearly all cases showed neurological or growth abnormalities, including substantial alterations of neuron populations and structural brain defects. Our results demonstrate the functional importance of ultraconserved enhancers and indicate that remarkably strong sequence conservation likely results from fitness deficits that appear subtle in a laboratory setting.


Assuntos
Sequência Conservada , Desenvolvimento Embrionário/genética , Elementos Facilitadores Genéticos , Animais , Encéfalo/anormalidades , Encéfalo/embriologia , Encéfalo/metabolismo , Feminino , Deleção de Genes , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Masculino , Camundongos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Nature ; 583(7818): 744-751, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32728240

RESUMO

The Encyclopedia of DNA Elements (ENCODE) project has established a genomic resource for mammalian development, profiling a diverse panel of mouse tissues at 8 developmental stages from 10.5 days after conception until birth, including transcriptomes, methylomes and chromatin states. Here we systematically examined the state and accessibility of chromatin in the developing mouse fetus. In total we performed 1,128 chromatin immunoprecipitation with sequencing (ChIP-seq) assays for histone modifications and 132 assay for transposase-accessible chromatin using sequencing (ATAC-seq) assays for chromatin accessibility across 72 distinct tissue-stages. We used integrative analysis to develop a unified set of chromatin state annotations, infer the identities of dynamic enhancers and key transcriptional regulators, and characterize the relationship between chromatin state and accessibility during developmental gene regulation. We also leveraged these data to link enhancers to putative target genes and demonstrate tissue-specific enrichments of sequence variants associated with disease in humans. The mouse ENCODE data sets provide a compendium of resources for biomedical researchers and achieve, to our knowledge, the most comprehensive view of chromatin dynamics during mammalian fetal development to date.


Assuntos
Cromatina/genética , Cromatina/metabolismo , Conjuntos de Dados como Assunto , Desenvolvimento Fetal/genética , Histonas/metabolismo , Anotação de Sequência Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Animais , Cromatina/química , Sequenciamento de Cromatina por Imunoprecipitação , Doença/genética , Elementos Facilitadores Genéticos/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Variação Genética , Histonas/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Reprodutibilidade dos Testes , Transposases/metabolismo
4.
J Nat Prod ; 87(7): 1826-1837, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38995621

RESUMO

Merkel cell carcinoma (MCC) is a rare and aggressive cutaneous cancer. Two new prenylated indole 2,5-diketopiperazine alkaloids, brevianamides E1 (1) and E2 (2), were isolated from a Penicillium fungus. Both compounds showed moderate cytotoxic activity against select MCC cell lines (i.e., MCC13, MKL-1, UISO, and WaGa) in the low micromolar range. The relative and absolute configurations of 1 and 2 were determined by combined approaches, including NOESY spectroscopy, DFT ECD and DP4 plus calculations, and Marfey's reaction. Literature research and the comparison of NMR and ECD data led to the structure revision of three previously reported natural analogues, notoamides K and P and asperversiamide L. The structurally unstable 1 and 2 underwent steady interconversion under neutral aqueous conditions. Investigation of the degradation of 2 in acidic methanol solutions led to the identification of a new methoxylated derivative (6) and two new ring-opened products (7 and 8) with the rearranged, elongated, 4-methylpent-3-ene side chain. The facile transformation of 2 to 7 and 8 was promoted by the intrinsic impurity (i.e., formaldehyde) of HPLC-grade methanol through the aza-Cope rearrangement.


Assuntos
Dicetopiperazinas , Penicillium , Penicillium/química , Dicetopiperazinas/farmacologia , Dicetopiperazinas/química , Estrutura Molecular , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais
5.
Nature ; 554(7691): 239-243, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29420474

RESUMO

Distant-acting tissue-specific enhancers, which regulate gene expression, vastly outnumber protein-coding genes in mammalian genomes, but the functional importance of this regulatory complexity remains unclear. Here we show that the pervasive presence of multiple enhancers with similar activities near the same gene confers phenotypic robustness to loss-of-function mutations in individual enhancers. We used genome editing to create 23 mouse deletion lines and inter-crosses, including both single and combinatorial enhancer deletions at seven distinct loci required for limb development. Unexpectedly, none of the ten deletions of individual enhancers caused noticeable changes in limb morphology. By contrast, the removal of pairs of limb enhancers near the same gene resulted in discernible phenotypes, indicating that enhancers function redundantly in establishing normal morphology. In a genetic background sensitized by reduced baseline expression of the target gene, even single enhancer deletions caused limb abnormalities, suggesting that functional redundancy is conferred by additive effects of enhancers on gene expression levels. A genome-wide analysis integrating epigenomic and transcriptomic data from 29 developmental mouse tissues revealed that mammalian genes are very commonly associated with multiple enhancers that have similar spatiotemporal activity. Systematic exploration of three representative developmental structures (limb, brain and heart) uncovered more than one thousand cases in which five or more enhancers with redundant activity patterns were found near the same gene. Together, our data indicate that enhancer redundancy is a remarkably widespread feature of mammalian genomes that provides an effective regulatory buffer to prevent deleterious phenotypic consequences upon the loss of individual enhancers.


Assuntos
Elementos Facilitadores Genéticos/genética , Extremidades/embriologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Fenótipo , Animais , Encéfalo/embriologia , Feminino , Genoma , Coração/embriologia , Deformidades Congênitas dos Membros/embriologia , Deformidades Congênitas dos Membros/genética , Masculino , Camundongos , Deleção de Sequência , Análise Espaço-Temporal
6.
J Environ Manage ; 352: 120137, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38266527

RESUMO

Using circular bio-based building materials is considered a promising solution to reduce the environmental impacts of the construction industry. To identify the pros and cons of these materials, it is essential to investigate their sustainability performance. However, the previous sustainability assessment studies are heterogeneous regarding the assessment methods and objectives, highlighting the need for a review to identify and analyse these aspects. Moreover, there is still a lack of studies reviewing the methodological issues and implications of the assessment methods, as well as the current end-of-life scenarios and circularity options for these materials. To address these gaps, this study conducts a systematic and critical review of a sample of 97 articles. The results indicate that Life Cycle Assessment (LCA) is the most frequently applied method, yet most studies are cradle-to-gate analyses of materials. Otherwise, very few studies consider the end-of-life phase, and most of the end-of-life scenarios analysed are unsustainable and have low circularity levels. The analysis also highlights the methodological issues of the assessment methods used, with a particular focus on LCA, such as a lack of consensus on system boundaries, functional units, and databases for facilitating sustainability assessments associated with the use of circular bio-based building materials. Two primary recommendations emerge from the analysis. Firstly, for LCA studies, it is recommended to increase transparency and harmonisation in assessments to improve the comparability of results. Besides, to overcome data availability issues, it is recommended to use data from multiple sources and conduct sensitivity and uncertainty analyses. Secondly, more sustainability assessments (including the three pillars) considering the whole life cycle with more sustainable end-of-life scenarios and circularity options for these materials should be conducted.


Assuntos
Indústria da Construção , Meio Ambiente , Materiais de Construção
7.
J Environ Manage ; 367: 121965, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39083948

RESUMO

Circular bio-based building materials (CBBMs) provide a potential solution to reduce the climate impacts of buildings and offer opportunities to transition the construction industry to a circular model. Promoting the use of these materials can also bring economic, environmental, and social benefits from valorising biowaste and by-products from other sectors. Despite their potential, CBBMs have not received sufficient attention globally, and their adoption is hindered by various barriers. However, it is unclear what the CBBMs' use status is, what adoption barriers exist, how these barriers interact, and what should be done to address them. This study addresses these knowledge gaps through a systematic study using mixed methods to investigate the adoption status and barriers to these materials in developed economies by using a specific case analysis in Flanders. The data analysis results show that hemp-based, cork-based, and straw-based materials are the most used, while the market for CBBMs is very limited in the region. Twenty-three potential adoption barriers were identified and selected from the existing literature, then ranked based on their mean scores. The t-test analysis helps to identify 13 critical barriers, which are grouped into five categories, including cost and risk-related barriers, technical and cultural-related barriers, the government's role-related barriers, information and quality-related barriers, and market-related barriers. Among them, cost and risk-related barriers, including "concern about the high initial cost", "risks and uncertainties involved in adopting new materials", and "perception of the extra cost being incurred", are the three most critical barriers to CBBM adoption in Flanders. Kendall's W test shows good consensus among the two expert groups-with and without hands-on experience in utilising CBBMs-in their rankings of the barriers. Meanwhile, the Mann-Whitney U test indicates no statistically significant differences in the ranks of barriers between the two expert groups. The interview results confirm almost all survey results and provide deeper insights into the status and barriers to adopting these materials. Practical and policy implications are discussed based on these findings to inform policy deliberations on promoting CBBMs. This study may also be a good reference for scholars and industry practitioners to better understand issues impacting decision-making towards the adoption of CBBMs in the construction industry.


Assuntos
Materiais de Construção , Bélgica , Indústria da Construção
8.
Lancet ; 397(10284): 1554-1563, 2021 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33894833

RESUMO

BACKGROUND: The use of intracytoplasmic sperm injection has increased substantially worldwide, primarily in couples with non-male factor infertility. However, there is a paucity of evidence from randomised trials supporting this approach compared with conventional in-vitro fertilisation (IVF). We aimed to investigate whether intracytoplasmic sperm injection would result in a higher livebirth rate compared with conventional IVF. METHODS: This open-label, multicentre, randomised trial was done at two IVF centres in Ho Chi Minh City, Vietnam (IVFMD, My Duc Hospital and IVFAS, An Sinh Hospital). Eligible couples were aged at least 18 years and the male partner's sperm count and motility (progressive motility) were normal based on WHO 2010 criteria. Couples had to have undergone two or fewer previous conventional IVF or intracytoplasmic sperm injection attempts, have used an antagonist protocol for ovarian stimulation, and agree to have two or fewer embryos transferred. Couples were randomly assigned (1:1) to undergo either intracytoplasmic sperm injection or conventional IVF, using block randomisation with variable block size of 2, 4, or 8 and a telephone-based central randomisation method. The computer-generated randomisation list was prepared by an independent statistician who had no other involvement in the study. Embryologists and couples were not masked to study groups because of the type of interventions and differences in hospital fees, but clinicians performing embryo transfer were unaware of study group allocation. The primary outcome was livebirth after the first embryo transfer from the initiated cycle. Analyses were done on an intention-to-treat basis. The trial is registered with ClinicalTrials.gov, NCT03428919. FINDINGS: Between March 16, 2018, and Aug 12, 2019, we randomly assigned 1064 couples to intracytoplasmic sperm injection (n=532) or conventional IVF (n=532). Livebirth after the first embryo transfer from the initiated cycle occurred in 184 (35%) of 532 couples randomly assigned to intracytoplasmic sperm injection and in 166 (31%) of 532 couples randomly assigned to conventional IVF (absolute difference 3·4%, 95% CI -2·4 to 9·2; risk ratio [RR] 1·11, 95% CI 0·93 to 1·32; p=0·27). 29 (5%) couples in the intracytoplasmic sperm injection group and 34 (6%) couples in the conventional IVF group had fertilisation failure (absolute difference -0·9%, -4·0 to 2·1, RR 0·85, 95% CI 0·53 to 1·38; p=0·60). INTERPRETATION: In couples with infertility in whom the male partner has a normal total sperm count and motility, intracytoplasmic sperm injection did not improve the livebirth rate compared with conventional IVF. Our results challenge the value of the routine use of intracytoplasmic sperm injection in assisted reproduction techniques for this population. FUNDING: My Duc Hospital and Merck Sharp and Dohme.


Assuntos
Fertilização in vitro/efeitos adversos , Infertilidade/terapia , Técnicas de Reprodução Assistida/estatística & dados numéricos , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Adulto , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Humanos , Análise de Intenção de Tratamento/métodos , Nascido Vivo/epidemiologia , Masculino , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Técnicas de Reprodução Assistida/tendências , Contagem de Espermatozoides/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Motilidade dos Espermatozoides/fisiologia , Vietnã/epidemiologia
9.
Arch Virol ; 167(4): 1131-1135, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174413

RESUMO

African swine fever virus (ASF) has circulated in Vietnam since 2018, causing significant losses to the pig industry. Quick, accurate diagnosis of African swine fever virus (ASFV) infection is crucial for controlling the disease. The detection of the virus in piglets with congenital tremors is described in this paper. ASFV was detected in brain tissues by polymerase chain reaction (PCR) and immunohistochemistry. Classical swine fever virus, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and pseudorabies virus were not detected by PCR, suggesting that the ASFV was the cause of these neurological signs.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Febre Suína Clássica , Vírus da Síndrome Respiratória e Reprodutiva Suína , Febre Suína Africana/diagnóstico , Vírus da Febre Suína Africana/genética , Animais , Suínos , Tremor
11.
N Engl J Med ; 379(14): 1322-1331, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30281988

RESUMO

BACKGROUND: Candida auris is an emerging and multidrug-resistant pathogen. Here we report the epidemiology of a hospital outbreak of C. auris colonization and infection. METHODS: After identification of a cluster of C. auris infections in the neurosciences intensive care unit (ICU) of the Oxford University Hospitals, United Kingdom, we instituted an intensive patient and environmental screening program and package of interventions. Multivariable logistic regression was used to identify predictors of C. auris colonization and infection. Isolates from patients and from the environment were analyzed by whole-genome sequencing. RESULTS: A total of 70 patients were identified as being colonized or infected with C. auris between February 2, 2015, and August 31, 2017; of these patients, 66 (94%) had been admitted to the neurosciences ICU before diagnosis. Invasive C. auris infections developed in 7 patients. When length of stay in the neurosciences ICU and patient vital signs and laboratory results were controlled for, the predictors of C. auris colonization or infection included the use of reusable skin-surface axillary temperature probes (multivariable odds ratio, 6.80; 95% confidence interval [CI], 2.96 to 15.63; P<0.001) and systemic fluconazole exposure (multivariable odds ratio, 10.34; 95% CI, 1.64 to 65.18; P=0.01). C. auris was rarely detected in the general environment. However, it was detected in isolates from reusable equipment, including multiple axillary skin-surface temperature probes. Despite a bundle of infection-control interventions, the incidence of new cases was reduced only after removal of the temperature probes. All outbreak sequences formed a single genetic cluster within the C. auris South African clade. The sequenced isolates from reusable equipment were genetically related to isolates from the patients. CONCLUSIONS: The transmission of C. auris in this hospital outbreak was found to be linked to reusable axillary temperature probes, indicating that this emerging pathogen can persist in the environment and be transmitted in health care settings. (Funded by the National Institute for Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance at Oxford University and others.).


Assuntos
Candida , Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Contaminação de Equipamentos , Reutilização de Equipamento , Controle de Infecções/métodos , Unidades de Terapia Intensiva , Termômetros/microbiologia , Adulto , Candida/genética , Candida/isolamento & purificação , Candidíase/mortalidade , Candidíase/transmissão , Estudos de Casos e Controles , Infecção Hospitalar/mortalidade , Infecção Hospitalar/transmissão , Feminino , Departamentos Hospitalares , Humanos , Incidência , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise Multivariada , Neurologia , Filogenia , Fatores de Risco , Reino Unido/epidemiologia
12.
Chem Senses ; 462021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33855345

RESUMO

We have characterized a recently rediscovered chemosensory structure at the rear of the mandibular mucosa in the mouse oral cavity originally reported in the 1980s. This consists of unorganized taste buds, not contained within troughs, associated with the ducts of an underlying minor salivary gland. Using whole-mount preparations of transgenic mice expressing green fluorescent protein under the promoter of taste-signaling-specific genes, we determined that the structure contains taste bud clusters and salivary gland orifices at the rear of each mandible, distal to the last molar and anterior to the ascending ramus. Immunohistochemical analysis shows in the retromolar taste buds expression of the taste receptors Tas2R131 and T1R3 and taste cascade molecules TrpM5, PLCß2, and GNAT3, consistent with type II taste cells, and expression of GAD1, consistent with type III taste cells. Furthermore, the neuronal marker, calcitonin gene-related peptide, in retromolar mucosa tissue wrapping around TrpM5+ taste buds was observed. RT-PCR showed that retromolar taste buds express all 3 mouse tas1r genes, 28 of the 35 tas2r genes, and taste transduction signaling genes gnat3, plcb2, and trpm5, making the retromolar taste buds similar to other lingual and palate taste buds. Finally, histochemistry demonstrated that the mandibular retromolar secretory gland is a minor salivary gland of mucous type. The mandibular retromolar taste structure may thus play a role in taste sensation and represent a potential novel pharmacological target for taste disorders.


Assuntos
Mandíbula/metabolismo , Muco/metabolismo , Glândulas Salivares/metabolismo , Papilas Gustativas/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL
13.
Artigo em Inglês | MEDLINE | ID: mdl-32205351

RESUMO

Resistance to amoxicillin-clavulanate, a widely used beta-lactam/beta-lactamase inhibitor combination antibiotic, is rising globally, and yet susceptibility testing remains challenging. To test whether whole-genome sequencing (WGS) could provide a more reliable assessment of susceptibility than traditional methods, we predicted resistance from WGS for 976 Escherichia coli bloodstream infection isolates from Oxfordshire, United Kingdom, comparing against phenotypes from the BD Phoenix (calibrated against EUCAST guidelines). A total of 339/976 (35%) isolates were amoxicillin-clavulanate resistant. Predictions based solely on beta-lactamase presence/absence performed poorly (sensitivity, 23% [78/339]) but improved when genetic features associated with penicillinase hyperproduction (e.g., promoter mutations and copy number estimates) were considered (sensitivity, 82% [277/339]; P < 0.0001). Most discrepancies occurred in isolates with MICs within ±1 doubling dilution of the breakpoint. We investigated two potential causes: the phenotypic reference and the binary resistant/susceptible classification. We performed reference standard, replicated phenotyping in a random stratified subsample of 261/976 (27%) isolates using agar dilution, following both EUCAST and CLSI guidelines, which use different clavulanate concentrations. As well as disagreeing with each other, neither agar dilution phenotype aligned perfectly with genetic features. A random-effects model investigating associations between genetic features and MICs showed that some genetic features had small, variable and additive effects, resulting in variable resistance classification. Using model fixed-effects to predict MICs for the non-agar dilution isolates, predicted MICs were in essential agreement (±1 doubling dilution) with observed (BD Phoenix) MICs for 691/715 (97%) isolates. This suggests amoxicillin-clavulanate resistance in E. coli is quantitative, rather than qualitative, explaining the poorly reproducible binary (resistant/susceptible) phenotypes and suboptimal concordance between different phenotypic methods and with WGS-based predictions.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio , Escherichia coli , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ácido Clavulânico/farmacologia , Escherichia coli/genética , Testes de Sensibilidade Microbiana , Fenótipo , Reino Unido , beta-Lactamases/genética
14.
BMC Med ; 18(1): 84, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32238164

RESUMO

BACKGROUND: Infective endocarditis is an uncommon but serious infection, where evidence for giving antibiotic prophylaxis before invasive dental procedures is inconclusive. In England, antibiotic prophylaxis was offered routinely to patients at risk of infective endocarditis until March 2008, when new guidelines aimed at reducing unnecessary antibiotic use were issued. We investigated whether changes in infective endocarditis incidence could be detected using electronic health records, assessing the impact of inclusion criteria/statistical model choice on inferences about the timing/type of any change. METHODS: Using national data from Hospital Episode Statistics covering 1998-2017, we modelled trends in infective endocarditis incidence using three different sets of inclusion criteria plus a range of regression models, identifying the most likely date for a change in trends if evidence for one existed. We also modelled trends in the proportions of different organism groups identified during infection episodes, using secondary diagnosis codes and data from national laboratory records. Lastly, we applied non-parametric local smoothing to visually inspect any changes in trend around the guideline change date. RESULTS: Infective endocarditis incidence increased markedly over the study (22.2-41.3 per million population in 1998 to 42.0-67.7 in 2017 depending on inclusion criteria). The most likely dates for a change in incidence trends ranged from September 2001 (uncertainty interval August 2000-May 2003) to May 2015 (March 1999-January 2016), depending on inclusion criteria and statistical model used. For the proportion of infective endocarditis cases associated with streptococci, the most likely change points ranged from October 2008 (March 2006-April 2010) to August 2015 (September 2013-November 2015), with those associated with oral streptococci decreasing in proportion after the change point. Smoothed trends showed no notable changes in trend around the guideline date. CONCLUSIONS: Infective endocarditis incidence has increased rapidly in England, though we did not detect any change in trends directly following the updated guidelines for antibiotic prophylaxis, either overall or in cases associated with oral streptococci. Estimates of when changes occurred were sensitive to inclusion criteria and statistical model choice, demonstrating the need for caution in interpreting single models when using large datasets. More research is needed to explore the factors behind this increase.


Assuntos
Antibioticoprofilaxia/métodos , Profilaxia Dentária/métodos , Registros Eletrônicos de Saúde/normas , Endocardite Bacteriana/prevenção & controle , Endocardite/prevenção & controle , Endocardite Bacteriana/etiologia , Inglaterra , Feminino , Humanos , Incidência , Masculino
15.
Osteoporos Int ; 31(11): 2219-2230, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623488

RESUMO

There is limited evidence regarding changes in bone microstructure in patients with hypoparathyroidism. In the current study, we used a non-invasive technique to assess bone structure in hypoparathyroidism patients and discovered site-specific changes which were mainly influenced by age and menstrual status. Such changes were more prominent in the trabeculae as well as in non-surgical as opposed to post-surgical patients. INTRODUCTION: Hypoparathyroidism (hypoPT) is a rare disease characterized by the lack of parathyroid hormone. There is limited evidence regarding changes in bone microstructure in patients with non-surgical hypoPT. We investigated bone microstructure of patients with non-surgical hypoPT using a non-invasive technique. METHODS: Patients with hypoPT were assessed using high-resolution peripheral quantitative computed tomography (HR-pQCT) and compared to age- and sex-matched healthy controls randomly selected from a pre-existing HR-pQCT database in a cross-sectional study. Preliminary comparison between patients with different etiologies of hypoPT was performed. Associations between bone microstructure and clinical parameters were investigated using correlation and regression analyses. RESULTS: A total of 94 patients with non-surgical hypoPT were recruited. Patients displayed an increase in trabecular volumetric BMD of the tibia (170.57 ± 34.32 vs. 156.48 ± 40.55 mg HA/cm3, p = 0.011) and increase in trabecular number of both the radius (1.48 ± 0.29 vs. 1.36 ± 0.22 mm-1, p = 0.003) and tibia (1.42 ± 0.23 vs. 1.24 ± 0.22 mm-1, p < 0.001) compared to healthy controls. Trabecular number was higher for non-surgical hypoPT compared to post-surgical hypoPT (1.37 ± 0.25 and 1.17 ± 0.13 mm-1, p = 0.022). Trends towards increase in cortical volumetric BMD were only present for post-menopausal female and male patients above the age of 50. For female patients, cortical volumetric BMD and area increased with age and decreased after menopause. For males, age had little influence on bone microstructure, but cortical porosity increased with longer treatment durations. CONCLUSIONS: Results from this pilot study suggested that both cortical and trabecular bone were altered in this group of patients with hypoPT. Etiology for hypoPT might influence bone microstructure, mainly on trabeculae. Age, menstrual status, and treatment duration were likely to influence bone microstructure in hypoPT.


Assuntos
Densidade Óssea , Hipoparatireoidismo , Adulto , Estudos Transversais , Feminino , Humanos , Hipoparatireoidismo/diagnóstico por imagem , Hipoparatireoidismo/etiologia , Masculino , Projetos Piloto , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem
16.
Clin Lab ; 66(12)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33337827

RESUMO

BACKGROUND: Although TSH suppression by elevated ß-hCG is essentially seen during first trimester, differences in TSH reference ranges between various countries have been reported. Physiologic changes during pregnancy may also influence FT4 assays. This study aims to establish method-specific reference intervals (RIs) of TSH, FT4, and FT3 in Vietnamese, first trimester pregnant women. METHODS: This cross-sectional study was conducted at My Duc Hospital, Ho Chi Minh, Vietnam. Women with singleton pregnancies in the first trimester and conceived naturally were included. Those with a history of thyroid disease, positive thyroid-specific autoantibodies, diffuse goiter or one thyroid nodule > 10 mm in size or ≥ 2 nodules detected by ultrasound, and taking medications affecting thyroid function were excluded. Serum TSH, FT4, and FT3 were measured by chemiluminescent detection technology on the Access 2 Immunoassay System (Beckman Coulter, Inc., USA). Intra- and interassay coefficients of variations (CV) were 3.6% and 4.4% for TSH, 5.4% and 6.1% for FT4, 6.6%, and 6.0% for FT3, respectively. The 2.5th and 97.5th percentiles were used to determine RIs. RESULTS: Between August 1, 2017, to December 1, 2018, there were 876 pregnant women who fulfilled inclusion and exclusion criteria. They had a mean age of 30.1 years, an average BMI of 21.3 kg/m2, and 77.3% of them were primigravida. The RIs for TSH, FT4 and FT3 were 0.17 - 2.35 mIU/L, 0.67 - 1.11 ng/dL and 2.82 - 3.90 pg/mL, respectively. CONCLUSIONS: Established RIs for TSH, FT4, and FT3 in Vietnamese women would help to reduce the misdiagnosis of gestational thyroid disorders.


Assuntos
Testes de Função Tireóidea , Tiroxina , Adulto , Povo Asiático , Estudos Transversais , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Gestantes , Valores de Referência , Tireotropina , Tri-Iodotironina
17.
Sensors (Basel) ; 20(9)2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380751

RESUMO

Facial expression recognition (FER) is a challenging problem in the fields of pattern recognition and computer vision. The recent success of convolutional neural networks (CNNs) in object detection and object segmentation tasks has shown promise in building an automatic deep CNN-based FER model. However, in real-world scenarios, performance degrades dramatically owing to the great diversity of factors unrelated to facial expressions, and due to a lack of training data and an intrinsic imbalance in the existing facial emotion datasets. To tackle these problems, this paper not only applies deep transfer learning techniques, but also proposes a novel loss function called weighted-cluster loss, which is used during the fine-tuning phase. Specifically, the weighted-cluster loss function simultaneously improves the intra-class compactness and the inter-class separability by learning a class center for each emotion class. It also takes the imbalance in a facial expression dataset into account by giving each emotion class a weight based on its proportion of the total number of images. In addition, a recent, successful deep CNN architecture, pre-trained in the task of face identification with the VGGFace2 database from the Visual Geometry Group at Oxford University, is employed and fine-tuned using the proposed loss function to recognize eight basic facial emotions from the AffectNet database of facial expression, valence, and arousal computing in the wild. Experiments on an AffectNet real-world facial dataset demonstrate that our method outperforms the baseline CNN models that use either weighted-softmax loss or center loss.


Assuntos
Reconhecimento Facial , Redes Neurais de Computação , Face , Expressão Facial , Humanos , Aprendizado de Máquina
18.
Zhonghua Nei Ke Za Zhi ; 59(1): 23-28, 2020 Jan 01.
Artigo em Zh | MEDLINE | ID: mdl-31887832

RESUMO

Objective: To investigate the association of GNA11 gene polymorphisms with the risk of adult-onset non-surgical hypoparathyroidism (Ns-HypoPT). Methods: Genotyping of GNA11 single nucleotide polymorphisms (SNPs) (rs28685098, rs4806907, rs11084997 and rs78003011) was carried out in 203 patients and 209 healthy participants by sequenom MassArray iPLEX System. These SNPs are located in promoter and 3'untranslated region (3'UTR) of GNA11 gene, respectively. Results: Allele and genotype frequencies of rs11084997 in patients were significantly different from those of controls (genotype GG:60.5% vs. 49.8%, GC: 35.5% vs. 41.6%, CC: 4.0% vs. 8.6%, P=0.038; G allele 78.3% vs. 70.6%, C allele 21.7% vs. 29.4%, P=0.012), and the C allele of rs11084997 carriers had a lower risk to develops Ns-HypoPT in additive and dominant genetic models [OR=0.382 (0.160-0.915), 0.647 (0.437-0.957)]. CC-Haplotype formed by the minor alleles of rs4806907 and rs11084997 was associated with a decreased risk of Ns-HypoPT in additive, dominant and recessive genetic model [OR=0.317 (0.126-0.801), 0.640 (0.430-0.952), 0.367 (0.148-0.912)]. Conclusion: The minor allele C of rs11084997 in GNA11 gene promoter was associated with decreased risk of Ns-HypoPT in Chinese population.


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/genética , Predisposição Genética para Doença , Hipoparatireoidismo/genética , Adulto , Alelos , Povo Asiático , Estudos de Casos e Controles , China , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Frequência do Gene , Genótipo , Humanos , Hipoparatireoidismo/diagnóstico , Polimorfismo de Nucleotídeo Único
19.
BMC Med ; 17(1): 169, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31481119

RESUMO

BACKGROUND: Diagnostic codes from electronic health records are widely used to assess patterns of disease. Infective endocarditis is an uncommon but serious infection, with objective diagnostic criteria. Electronic health records have been used to explore the impact of changing guidance on antibiotic prophylaxis for dental procedures on incidence, but limited data on the accuracy of the diagnostic codes exists. Endocarditis was used as a clinically relevant case study to investigate the relationship between clinical cases and diagnostic codes, to understand discrepancies and to improve design of future studies. METHODS: Electronic health record data from two UK tertiary care centres were linked with data from a prospectively collected clinical endocarditis service database (Leeds Teaching Hospital) or retrospective clinical audit and microbiology laboratory blood culture results (Oxford University Hospitals Trust). The relationship between diagnostic codes for endocarditis and confirmed clinical cases according to the objective Duke criteria was assessed, and impact on estimations of disease incidence and trends. RESULTS: In Leeds 2006-2016, 738/1681(44%) admissions containing any endocarditis code represented a definite/possible case, whilst 263/1001(24%) definite/possible endocarditis cases had no endocarditis code assigned. In Oxford 2010-2016, 307/552(56%) reviewed endocarditis-coded admissions represented a clinical case. Diagnostic codes used by most endocarditis studies had good positive predictive value (PPV) but low sensitivity (e.g. I33-primary 82% and 43% respectively); one (I38-secondary) had PPV under 6%. Estimating endocarditis incidence using raw admission data overestimated incidence trends twofold. Removing records with non-specific codes, very short stays and readmissions improved predictive ability. Estimating incidence of streptococcal endocarditis using secondary codes also overestimated increases in incidence over time. Reasons for discrepancies included changes in coding behaviour over time, and coding guidance allowing assignment of a code mentioning 'endocarditis' where endocarditis was never mentioned in the clinical notes. CONCLUSIONS: Commonly used diagnostic codes in studies of endocarditis had good predictive ability. Other apparently plausible codes were poorly predictive. Use of diagnostic codes without examining sensitivity and predictive ability can give inaccurate estimations of incidence and trends. Similar considerations may apply to other diseases. Health record studies require validation of diagnostic codes and careful data curation to minimise risk of serious errors.


Assuntos
Codificação Clínica/normas , Registros Eletrônicos de Saúde/normas , Endocardite/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Incidência , Classificação Internacional de Doenças , Estudos Retrospectivos
20.
Lancet ; 390(10089): 62-72, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28499548

RESUMO

BACKGROUND: Weekend hospital admission is associated with increased mortality, but the contributions of varying illness severity and admission time to this weekend effect remain unexplored. METHODS: We analysed unselected emergency admissions to four Oxford University National Health Service hospitals in the UK from Jan 1, 2006, to Dec 31, 2014. The primary outcome was death within 30 days of admission (in or out of hospital), analysed using Cox models measuring time from admission. The primary exposure was day of the week of admission. We adjusted for multiple confounders including demographics, comorbidities, and admission characteristics, incorporating non-linearity and interactions. Models then considered the effect of adjusting for 15 common haematology and biochemistry test results or proxies for hospital workload. FINDINGS: 257 596 individuals underwent 503 938 emergency admissions. 18 313 (4·7%) patients admitted as weekday energency admissions and 6070 (5·1%) patients admitted as weekend emergency admissions died within 30 days (p<0·0001). 9347 individuals underwent 9707 emergency admissions on public holidays. 559 (5·8%) died within 30 days (p<0·0001 vs weekday). 15 routine haematology and biochemistry test results were highly prognostic for mortality. In 271 465 (53·9%) admissions with complete data, adjustment for test results explained 33% (95% CI 21 to 70) of the excess mortality associated with emergency admission on Saturdays compared with Wednesdays, 52% (lower 95% CI 34) on Sundays, and 87% (lower 95% CI 45) on public holidays after adjustment for standard patient characteristics. Excess mortality was predominantly restricted to admissions between 1100 h and 1500 h (pinteraction=0·04). No hospital workload measure was independently associated with mortality (all p values >0·06). INTERPRETATION: Adjustment for routine test results substantially reduced excess mortality associated with emergency admission at weekends and public holidays. Adjustment for patient-level factors not available in our study might further reduce the residual excess mortality, particularly as this clustered around midday at weekends. Hospital workload was not associated with mortality. Together, these findings suggest that the weekend effect arises from patient-level differences at admission rather than reduced hospital staffing or services. FUNDING: NIHR Oxford Biomedical Research Centre.


Assuntos
Plantão Médico/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Mortalidade , Admissão do Paciente/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupos Diagnósticos Relacionados/estatística & dados numéricos , Registros Eletrônicos de Saúde , Emergências , Inglaterra/epidemiologia , Feminino , Férias e Feriados , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Medição de Risco/métodos , Medicina Estatal/estatística & dados numéricos
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