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1.
Lett Appl Microbiol ; 73(4): 529-541, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34265084

RESUMO

Fish intestine contains different types of microbiomes, and bacteria are the dominant microbiota in fishes. Studies have identified various core gut bacteria in fishes. However, little is known about the composition and their relative functions of gut microbial community along the intestine. To explore this, the current study investigated the microbial community distribution along the gut in Anguilla japonica. By 16S rRNA gene sequencing, we profiled the gut microbiota in eel along the three regions (anterior intestine (AI), the middle intestine (MI) and the posterior intestine (PI)). Results suggested that the three regions did not have significant differences on the observed species and diversities. The cluster tree analysis showed that the bacteria community in MI was closer to PI than the AI. The dominant bacteria in AI were the Proteobacteria, in which the majority was graduated replaced by Bacteroidetes along the gut to PI region. Through PICRUSt analysis, shifts in the bacterial community along the gut were found to affect the genetic information processing pathways. Higher levels of translation and transcriptional pathway activities were found in MI and PI than in AI. The dominant bacterial species were different among the regions and contributed to various biological functions along the gut.


Assuntos
Anguilla , Microbioma Gastrointestinal , Microbiota , Animais , Bactérias/genética , RNA Ribossômico 16S/genética
2.
Heredity (Edinb) ; 119(5): 388, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28792490

RESUMO

This corrects the article DOI: 10.1038/hdy.2015.89.

3.
Heredity (Edinb) ; 116(2): 190-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26419336

RESUMO

Whole-genome duplication (WGD) results in new genomic resources that can be exploited by evolution for rewiring genetic regulatory networks in organisms. In metazoans, WGD occurred before the last common ancestor of vertebrates, and has been postulated as a major evolutionary force that contributed to their speciation and diversification of morphological structures. Here, we have sequenced genomes from three of the four extant species of horseshoe crabs-Carcinoscorpius rotundicauda, Limulus polyphemus and Tachypleus tridentatus. Phylogenetic and sequence analyses of their Hox and other homeobox genes, which encode crucial transcription factors and have been used as indicators of WGD in animals, strongly suggests that WGD happened before the last common ancestor of these marine chelicerates >135 million years ago. Signatures of subfunctionalisation of paralogues of Hox genes are revealed in the appendages of two species of horseshoe crabs. Further, residual homeobox pseudogenes are observed in the three lineages. The existence of WGD in the horseshoe crabs, noted for relative morphological stasis over geological time, suggests that genomic diversity need not always be reflected phenotypically, in contrast to the suggested situation in vertebrates. This study provides evidence of ancient WGD in the ecdysozoan lineage, and reveals new opportunities for studying genomic and regulatory evolution after WGD in the Metazoa.


Assuntos
Duplicação Gênica , Genoma , Caranguejos Ferradura/genética , Filogenia , Sequência de Aminoácidos , Animais , Evolução Biológica , Genes Homeobox , Dados de Sequência Molecular , Análise de Sequência de DNA
6.
Diabetologia ; 56(6): 1291-305, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23532257

RESUMO

AIMS/HYPOTHESIS: Most genetic variants identified for type 2 diabetes have been discovered in European populations. We performed genome-wide association studies (GWAS) in a Chinese population with the aim of identifying novel variants for type 2 diabetes in Asians. METHODS: We performed a meta-analysis of three GWAS comprising 684 patients with type 2 diabetes and 955 controls of Southern Han Chinese descent. We followed up the top signals in two independent Southern Han Chinese cohorts (totalling 10,383 cases and 6,974 controls), and performed in silico replication in multiple populations. RESULTS: We identified CDKN2A/B and four novel type 2 diabetes association signals with p < 1 × 10(-5) from the meta-analysis. Thirteen variants within these four loci were followed up in two independent Chinese cohorts, and rs10229583 at 7q32 was found to be associated with type 2 diabetes in a combined analysis of 11,067 cases and 7,929 controls (p meta = 2.6 × 10(-8); OR [95% CI] 1.18 [1.11, 1.25]). In silico replication revealed consistent associations across multiethnic groups, including five East Asian populations (p meta = 2.3 × 10(-10)) and a population of European descent (p = 8.6 × 10(-3)). The rs10229583 risk variant was associated with elevated fasting plasma glucose, impaired beta cell function in controls, and an earlier age at diagnosis for the cases. The novel variant lies within an islet-selective cluster of open regulatory elements. There was significant heterogeneity of effect between Han Chinese and individuals of European descent, Malaysians and Indians. CONCLUSIONS/INTERPRETATION: Our study identifies rs10229583 near PAX4 as a novel locus for type 2 diabetes in Chinese and other populations and provides new insights into the pathogenesis of type 2 diabetes.


Assuntos
Cromossomos Humanos Par 7 , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Adulto , Idoso , Povo Asiático , China , Diabetes Mellitus Tipo 2/etnologia , Feminino , Marcadores Genéticos , Variação Genética , Genótipo , Hong Kong , Humanos , Células Secretoras de Insulina/citologia , Japão , Masculino , Pessoa de Meia-Idade , Singapura
7.
BJPsych Int ; 18(1): 18-22, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34287405

RESUMO

People with common mental disorders often seek medical attention from their family doctors. Thus, it is essential for family doctors to possess primary mental health knowledge. The aim of this study was to understand whether psychiatrists endorse the primary mental health competencies identified by the World Organization of Family Doctors and whether they agree that family doctors are demonstrating these competencies. A questionnaire was constructed based on 32 core competencies. Presidents of all World Psychiatric Association member societies were invited to complete the questionnaire or to forward it to local experts. According to the respondents, these competencies are considered relevant yet not sufficiently possessed by typical primary care doctors. Proposals are made to bridge this assumed competency gap.

9.
Curr Biol ; 10(14): 861-4, 2000 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-10899009

RESUMO

The functional diversity and structural heterogeneity of microtubules are largely determined by microtubule-associated proteins (MAPs) [1] [2]. Bik1p (bilateral karyogamy defect protein) is one of the MAPs required for microtubule assembly, stability and function in cell processes such as karyogamy and nuclear migration and positioning in the yeast Saccharomyces cerevisiae [3]. The macrocyclic immunosuppressive antibiotic rapamycin, complexed with its binding protein FKBP12, binds to and inhibits the target of rapamycin protein (TOR) in yeast [4] [5]. We report here that TOR physically interacts with Bik1p, the yeast homolog of human CLIP-170/Restin [6] [7]. Inhibition of TOR by rapamycin significantly affects microtubule assembly, elongation and stability. This function of TOR is independent of new protein synthesis. Rapamycin also causes defects in spindle orientation, nuclear movement and positioning, karyogamy and chromosomal stability, defects also found in the bikDelta mutant. Our data suggest a role for TOR signaling in regulating microtubule stability and function, possibly through Bik1p.


Assuntos
Proteínas Fúngicas/fisiologia , Microtúbulos/fisiologia , Humanos , Microtúbulos/efeitos dos fármacos , Mutação , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Transdução de Sinais , Sirolimo/farmacologia , Fuso Acromático/efeitos dos fármacos
10.
Oncogene ; 35(49): 6271-6280, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27132506

RESUMO

Epidemiological studies showed that obesity and its related non-alcoholic fatty liver disease (NAFLD) promote hepatocellular carcinoma (HCC) development. We aimed to uncover the genetic alterations of NAFLD-HCC using whole-exome sequencing. We compared HCC development in genetically obese mice and dietary obese mice with wild-type lean mice fed a normal chow after treatment with diethylnitrosamine. HCC tumor and adjacent normal samples from obese and lean mice were then subjected to whole-exome sequencing. Functional and mechanistic importance of the identified mutations in Carboxyl ester lipase (Cel) gene and Harvey rat sarcoma virus oncogene 1 (Hras) was further elucidated. We demonstrated significantly higher incidences of HCC in both genetic and dietary obese mice with NAFLD development as compared with lean mice without NAFLD. The mutational signatures of NAFLD-HCC and lean HCC were distinct, with <3% overlapped. Eight metabolic or oncogenic pathways were found to be significantly enriched by mutated genes in NAFLD-HCC, but only two of these pathways were dysregulated by mutations in lean HCC. In particular, Cel was mutated significantly more frequently in NAFLD-HCC than in lean HCC. The multiple-site mutations in Cel are loss-of-function mutations, with effects similar to Cel knock-down. Mutant Cel caused accumulation of cholesteryl ester in liver cells, which led to induction of endoplasmic reticulum stress and consequently activated the IRE1α/c-Jun N-terminal kinase (JNK)/c-Jun/activating protein-1 (AP-1) signaling cascade to promote liver cell growth. In addition, single-site mutations in Hras at codon 61 were found in NAFLD-HCC but none in lean HCC. The gain-of-function mutations in Hras (Q61R and Q61K) significantly promoted liver cell growth through activating the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt pathways. In conclusion, we have identified mutation signature and pathways in NAFLD-associated HCC. Mutations in Cel and Hras have important roles in NAFLD-associated hepatocellular carcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Obesidade/genética , Animais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Obesidade/complicações , Obesidade/patologia , Transdução de Sinais
11.
Toxicol In Vitro ; 17(2): 139-43, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12650666

RESUMO

Exposure to arsenic has been reported to cause DNA damage and eventually the occurrence of bladder, lung and skin cancers. A previous report has demonstrated that arsenite-induced phosphorylation of Mre11, a protein involved in the repair of DNA double strand breaks (DSBs), is M phase-dependent and requires the Nijmegen breakage syndrome (NBS) protein, NBS1 [DNA Repair 1 (2002) 137]. Furthermore, arsenite treatment arrests cells at the M phase and the cells eventually go through apoptosis [Biochemical Pharmacology 60 (2000) 771]. Here we demonstrate that arsenite treatment enhances the generation of nitric oxide (NO), and that the enhanced NO generation is dominant at the G2/M phase. Arsenite-induced NO generation is impaired in DSB repair-defective NBS cells, but not in NBS1-reconstituted NBS cells, suggesting NBS1 is required for effective NO generation. In summary, our study showed, for the first time, that arsenite-induced NO generation is cell-cycle- and NBS1-dependent.


Assuntos
Arsenitos/toxicidade , Proteínas de Ciclo Celular/metabolismo , Fase G2/efeitos dos fármacos , Mitose/efeitos dos fármacos , Óxido Nítrico/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Ciclo Celular/fisiologia , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Proteína Homóloga a MRE11 , Proteínas Nucleares/fisiologia , Fosforilação , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/metabolismo
12.
IEEE Trans Image Process ; 7(3): 304-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18276250

RESUMO

We propose a new definition of the total variation (TV) norm for vector-valued functions that can be applied to restore color and other vector-valued images. The new TV norm has the desirable properties of 1) not penalizing discontinuities (edges) in the image, 2) being rotationally invariant in the image space, and 3) reducing to the usual TV norm in the scalar case. Some numerical experiments on denoising simple color images in red-green-blue (RGB) color space are presented.

13.
IEEE Trans Image Process ; 7(3): 370-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-18276257

RESUMO

In this paper, we present a blind deconvolution algorithm based on the total variational (TV) minimization method proposed. The motivation for regularizing with the TV norm is that it is extremely effective for recovering edges of images as well as some blurring functions, e.g., motion blur and out-of-focus blur. An alternating minimization (AM)implicit iterative scheme is devised to recover the image and simultaneously identify the point spread function (psf). Numerical results indicate that the iterative scheme is quite robust, converges very fast (especially for discontinuous blur), and both the image and the psf can be recovered under the presence of high noise level. Finally, we remark that psf's without sharp edges, e.g., Gaussian blur, can also be identified through the TV approach.

14.
IEEE Trans Image Process ; 10(2): 266-77, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249617

RESUMO

We propose a new model for active contours to detect objects in a given image, based on techniques of curve evolution, Mumford-Shah (1989) functional for segmentation and level sets. Our model can detect objects whose boundaries are not necessarily defined by the gradient. We minimize an energy which can be seen as a particular case of the minimal partition problem. In the level set formulation, the problem becomes a "mean-curvature flow"-like evolving the active contour, which will stop on the desired boundary. However, the stopping term does not depend on the gradient of the image, as in the classical active contour models, but is instead related to a particular segmentation of the image. We give a numerical algorithm using finite differences. Finally, we present various experimental results and in particular some examples for which the classical snakes methods based on the gradient are not applicable. Also, the initial curve can be anywhere in the image, and interior contours are automatically detected.

15.
IEEE Trans Image Process ; 10(2): 231-41, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18249614

RESUMO

Motivated by the classical TV (total variation) restoration model, we propose a new nonlinear filter-the digital TV filter for denoising and enhancing digital images, or more generally, data living on graphs. The digital TV filter is a data dependent lowpass filter, capable of denoising data without blurring jumps or edges. In iterations, it solves a global total variational (or L(1)) optimization problem, which differs from most statistical filters. Applications are given in the denoising of one dimensional (1-D) signals, two-dimensional (2-D) data with irregular structures, gray scale and color images, and nonflat image features such as chromaticity.

16.
IEEE Trans Image Process ; 8(10): 1472-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-18267422

RESUMO

In PDE image restoration problems, one has to invert operators which is a sum of a blurring operator and an elliptic operator with highly varying coefficient. We present a preconditioner for such operators, which can be used with the conjugate gradient (CG) method, and compare it with Vogel and Oman's product preconditioner.

17.
Hong Kong Med J ; 8(2): 99-105, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11937664

RESUMO

Implementation of anaesthesia begins with a preoperative assessment of the surgical patient and development of an anaesthetic plan. Preparation of the patient includes the preoperative assessment, review of preoperative tests, optimisation of medical conditions, adequate preoperative fasting, appropriate premedication, and the explanation of anaesthetic risk to patients. The goals of preoperative preparation are to reduce the morbidity of surgery, to increase the quality while decreasing the cost of perioperative care, and to return the patient to desirable functioning as quickly as possible. A knowledgeable anaesthesiologist is the 'final clinical gatekeeper', who coordinates perioperative management and ensures that the patient is in the optimal state for anaesthesia and surgery.


Assuntos
Anestesiologia/normas , Cuidados Pré-Operatórios/normas , Qualidade da Assistência à Saúde , Adulto , Criança , Testes Diagnósticos de Rotina , Jejum , Humanos , Anamnese , Morbidade , Exame Físico , Pré-Medicação , Medição de Risco
18.
Health Phys ; 68(5): 716-8, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7730070

RESUMO

Standardized activated charcoal canisters (according to the U.S. EPA) have been used to collect radon exhaled from concrete surfaces covered with thin plaster (categorically different from thick plaster) of 32 buildings of different ages (0.5-31 y) in Hong Kong. Concrete surfaces covered with thin plaster is the commonest wall configuration in Hong Kong. The canisters are analyzed using gamma spectroscopy to obtain the radon exhalation rates. The results show that the radon exhalation rate decreases with the building age.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Habitação , Radônio/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Fenômenos Biofísicos , Biofísica , Hong Kong , Humanos , Doses de Radiação , Radônio/efeitos adversos , Fatores de Tempo
19.
Psychol Rep ; 79(3 Pt 2): 1296-8, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9009782

RESUMO

An excess of schizophrenia has been observed in the biological relatives of adoptees with schizophrenia. The present analysis examined the possibility that illness observed among 90 half-siblings may have been influenced by assortative mating resulting in excess illness in the biological parents of the half-siblings not biologically related to the adoptees (the coparents). We found no difference in the prevalence of mental illness between 44 index and 26 control coparents.


Assuntos
Adoção/psicologia , Filho de Pais com Deficiência/psicologia , Esquizofrenia/genética , Relações entre Irmãos , Meio Social , Adulto , Dinamarca , Feminino , Humanos , Masculino , Modelos Genéticos , Fenótipo , Fatores de Risco , Esquizofrenia/diagnóstico , Transtorno da Personalidade Esquizotípica/diagnóstico , Transtorno da Personalidade Esquizotípica/genética , Transtorno da Personalidade Esquizotípica/psicologia
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