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1.
Diabetes Metab ; 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31786360

RESUMO

AIM: The association between liver fibrosis (LF), as assessed by either histology or liver stiffness measurement (LSM), and the presence of early kidney dysfunction (EKD) was investigated in this study, as was also the diagnostic performance of LSM for identifying the presence of EKD in patients with non-alcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: A total of 214 adults with non-cirrhotic biopsy-proven NAFLD were recruited from two independent medical centres. Their histological stage of LF was quantified using Brunt's criteria. Vibration-controlled transient elastography (TE), using M-probe (FibroScan®) ultrasound, was performed in 154 patients and defined as significant when LSM was ≥ 8.0 kPa. EKD was defined as the presence of microalbuminuria with an estimated glomerular filtration rate ≥ 60 mL/min/1.73 m2. Logistic regression modelling was used to estimate the likelihood of having EKD with NAFLD (LSM-EKD model). RESULTS: The prevalence of EKD was higher in patients with vs without LF on histology (22.14% vs 4.82%, respectively; P < 0.001) and, similarly, EKD prevalence was higher in patients with LSM ≥ 8.0 kPa vs LSM < 8.0 kPa (23.81% vs 6.59%, respectively; P < 0.05). The area under the ROC curve of the LSM-EKD model for identifying EKD was 0.80 (95% CI: 0.72-0.89). LF detected by either method was associated with EKD independently of established renal risk factors and potential confounders. CONCLUSION: LF was independently associated with EKD in patients with biopsy-proven NAFLD. Thus, TE-measured LSM, a widely used technique for quantifying LF, can accurately identify those patients with NAFLD who are at risk of having EKD.

2.
BMC Bioinformatics ; 20(Suppl 16): 587, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31787071

RESUMO

BACKGROUND: Malignant liver tumor is one of the main causes of human death. In order to help physician better diagnose and make personalized treatment schemes, in clinical practice, it is often necessary to segment and visualize the liver tumor from abdominal computed tomography images. Due to the large number of slices in computed tomography sequence, developing an automatic and reliable segmentation method is very favored by physicians. However, because of the noise existed in the scan sequence and the similar pixel intensity of liver tumors with their surrounding tissues, besides, the size, position and shape of tumors also vary from one patient to another, automatic liver tumor segmentation is still a difficult task. RESULTS: We perform the proposed algorithm to the Liver Tumor Segmentation Challenge dataset and evaluate the segmentation results. Experimental results reveal that the proposed method achieved an average Dice score of 68.4% for tumor segmentation by using the designed network, and ASD, MSD, VOE and RVD improved from 27.8 to 21, 147 to 124, 0.52 to 0.46 and 0.69 to 0.73, respectively after performing adversarial training strategy, which proved the effectiveness of the proposed method. CONCLUSIONS: The testing results show that the proposed method achieves improved performance, which corroborated the adversarial training based strategy can achieve more accurate and robustness results on liver tumor segmentation task.

3.
Org Lett ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31802671

RESUMO

By making use of a direct C-H activation strategy, an efficient osmium(II)-catalyzed redox-neutral [4 + 2] annulation of N-methoxybenzamides with alkynes has been accomplished. Computational and experimental studies revealed that such transformation leading to the synthesis of the isoquinolone core might follow an Os(II)-Os(IV)-Os(II) catalytic pathway, in which an unusual HOAc-assisted oxidative addition of osmium(II) into the N-O bond to generate the osmium(IV) species was involved as one of the key transition states. Further exploration of divergent C-H activation reaction modes enabled by the osmium(II) catalyst has also been exemplified for one-pot assembly of other either linear or cyclic products.

4.
Artif Cells Nanomed Biotechnol ; 47(1): 4139-4148, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31698961

RESUMO

Numerous studies have investigated the prognostic significance of ECT2 (epithelial cell transforming sequence 2) expression in patients with cancer. Nevertheless, conflicting results have been obtained. We thus performed a meta-analysis to systematically assess the prognostic significance of ECT2 in cancer. Electronic databases (PubMed and EMBASE) were searched for eligible studies. Hazard ratios (HR) and odds ratios (OR) with 95% confidence intervals (CIs) were used to estimate effect sizes. A total of 5,305 patients from 19 articles and 21 studies were included. The pooled results revealed that high ECT2 expression was correlated with advanced TNM stage (OR = 2.17; 95% CI: 1.42-3.32), positive lymph node metastasis (OR = 2.98; 95% CI: 2.28-3.89), distant metastasis (OR = 2.25; 95% CI: 1.03-4.92), and poor tumour differentiation (OR = 2.25; 95% CI: 1.03-4.92). More importantly, high ECT2 expression was significantly associated with poor overall survival (HR = 2.26; 95% CI, 1.84-2.78) and recurrence-free survival (HR = 1.52; 95% CI, 1.24-1.86). Our results suggested that ECT2 is a promising prognostic indicator and therapeutic target for cancer.

5.
Nucleic Acids Res ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701131

RESUMO

Comprehensive genomic analyses of cancers have revealed substantial intrapatient molecular heterogeneities that may explain some instances of drug resistance and treatment failures. Examination of the clonal composition of an individual tumor and its evolution through disease progression and treatment may enable identification of precise therapeutic targets for drug design. Multi-region and single-cell sequencing are powerful tools that can be used to capture intratumor heterogeneity. Here, we present a database we've named CancerTracer (http://cailab.labshare.cn/cancertracer): a manually curated database designed to track and characterize the evolutionary trajectories of tumor growth in individual patients. We collected over 6000 tumor samples from 1548 patients corresponding to 45 different types of cancer. Patient-specific tumor phylogenetic trees were constructed based on somatic mutations or copy number alterations identified in multiple biopsies. Using the structured heterogeneity data, researchers can identify common driver events shared by all tumor regions, and the heterogeneous somatic events present in different regions of a tumor of interest. The database can also be used to investigate the phylogenetic relationships between primary and metastatic tumors. It is our hope that CancerTracer will significantly improve our understanding of the evolutionary histories of tumors, and may facilitate the identification of predictive biomarkers for personalized cancer therapies.

6.
Lancet Neurol ; 18(12): 1091-1102, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701892

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) in Parkinson's disease have increased the scope of biological knowledge about the disease over the past decade. We aimed to use the largest aggregate of GWAS data to identify novel risk loci and gain further insight into the causes of Parkinson's disease. METHODS: We did a meta-analysis of 17 datasets from Parkinson's disease GWAS available from European ancestry samples to nominate novel loci for disease risk. These datasets incorporated all available data. We then used these data to estimate heritable risk and develop predictive models of this heritability. We also used large gene expression and methylation resources to examine possible functional consequences as well as tissue, cell type, and biological pathway enrichments for the identified risk factors. Additionally, we examined shared genetic risk between Parkinson's disease and other phenotypes of interest via genetic correlations followed by Mendelian randomisation. FINDINGS: Between Oct 1, 2017, and Aug 9, 2018, we analysed 7·8 million single nucleotide polymorphisms in 37 688 cases, 18 618 UK Biobank proxy-cases (ie, individuals who do not have Parkinson's disease but have a first degree relative that does), and 1·4 million controls. We identified 90 independent genome-wide significant risk signals across 78 genomic regions, including 38 novel independent risk signals in 37 loci. These 90 variants explained 16-36% of the heritable risk of Parkinson's disease depending on prevalence. Integrating methylation and expression data within a Mendelian randomisation framework identified putatively associated genes at 70 risk signals underlying GWAS loci for follow-up functional studies. Tissue-specific expression enrichment analyses suggested Parkinson's disease loci were heavily brain-enriched, with specific neuronal cell types being implicated from single cell data. We found significant genetic correlations with brain volumes (false discovery rate-adjusted p=0·0035 for intracranial volume, p=0·024 for putamen volume), smoking status (p=0·024), and educational attainment (p=0·038). Mendelian randomisation between cognitive performance and Parkinson's disease risk showed a robust association (p=8·00 × 10-7). INTERPRETATION: These data provide the most comprehensive survey of genetic risk within Parkinson's disease to date, to the best of our knowledge, by revealing many additional Parkinson's disease risk loci, providing a biological context for these risk factors, and showing that a considerable genetic component of this disease remains unidentified. These associations derived from European ancestry datasets will need to be followed-up with more diverse data. FUNDING: The National Institute on Aging at the National Institutes of Health (USA), The Michael J Fox Foundation, and The Parkinson's Foundation (see appendix for full list of funding sources).

7.
Nano Lett ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31693379

RESUMO

Dielectric metasurfaces have recently been shown to provide an excellent platform for the harmonic generation of light due to their low optical absorption and to the strong electromagnetic field enhancement that can be designed into their constituent meta-atoms. Here, we demonstrate vacuum ultraviolet (VUV) third harmonic generation from a specially designed dielectric metasurface consisting of a titanium dioxide (TiO2) nanostructure array. The metasurface was designed to enhance the generation of VUV light at a wavelength of 185 nm by tailoring its geometric design parameters to achieve an optical resonance at the fundamental laser wavelength of 555 nm. The metasurface exhibits an enhancement factor of nominally 180 compared to an unpatterned TiO2 thin film of the same thickness, evidence of strong field enhancement at the fundamental wavelength. Mode analysis reveals that the origin of the enhancement is an anapole resonance near the pump wavelength. This work demonstrates an effective strategy for the compact generation of VUV light that could enable expanded access to this useful region of the electromagnetic spectrum.

8.
Nat Commun ; 10(1): 5086, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704910

RESUMO

Accurate prediction of an individual's phenotype from their DNA sequence is one of the great promises of genomics and precision medicine. We extend a powerful individual-level data Bayesian multiple regression model (BayesR) to one that utilises summary statistics from genome-wide association studies (GWAS), SBayesR. In simulation and cross-validation using 12 real traits and 1.1 million variants on 350,000 individuals from the UK Biobank, SBayesR improves prediction accuracy relative to commonly used state-of-the-art summary statistics methods at a fraction of the computational resources. Furthermore, using summary statistics for variants from the largest GWAS meta-analysis (n ≈ 700, 000) on height and BMI, we show that on average across traits and two independent data sets that SBayesR improves prediction R2 by 5.2% relative to LDpred and by 26.5% relative to clumping and p value thresholding.

9.
World J Surg Oncol ; 17(1): 187, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31706343

RESUMO

BACKGROUND: The purpose of this research was to assess the feasibility of reconstructing the middle hepatic vein (MHV) with resected left portal vein during left hemihepatectomy. METHODS: From January 2014 to January 2018, six patients received left hemihepatectomy combined with MHV reconstruction using the resected left portal vein in West China Hospital. We reviewed the clinical data including patient details, surgical technique, graft patency, and operative results. RESULTS: All six patients underwent left hemihepatectomy for liver tumors located at left hepatocaval confluence. In these patients, MHV was resected due to tumor invading and reconstructed using the resected left portal vein as graft. The mean operating time was 316 min. Two patients developed complications: one experienced bile leakage and one experienced pleural effusion. No patient developed vascular graft complications. All the grafts remained unobstructed, and no local tumor recurrence occurred during the observation period of 13-41 months. CONCLUSIONS: Our results indicated that the left portal vein was a safe graft for hepatic vein reconstruction. In addition, left hemihepatectomy combined with middle hepatic vein resection and reconstruction using the left portal vein can be performed safely to treat liver tumors located at hepatocaval confluence.

10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 568-570, 2019 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-31721510

RESUMO

Dens invaginatusis a rare malformation of the teeth, resulting in frequent pulp necrosis and chronic apical periodontitis. In this paper, the apical barrier technology was used to treat a case of chronic apical periodontitis caused by type Ⅱ dens invaginatus.


Assuntos
Dens in Dente , Periodontite Periapical , Necrose da Polpa Dentária , Humanos , Incisivo , Tratamento do Canal Radicular
11.
J Cell Mol Med ; 2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31736204

RESUMO

Patients with diabetes have an increased risk of vascular complications. Suv39h1, a histone methyltransferase, plays a protective role against myocardial injury in diabetes. Herein, we intend to explore whether Suv39h1 could affect neointimal formation after vascular injury in diabetic rats and reveal the underlying mechanism. In this study, we generated adenovirus expressing Suv39h1 as well as lentivirus expressing Suv39h1-targeting shRNA and evaluated the significance of Suv39h1 in vascular smooth muscle cells (VSMCs) under diabetic conditions. In vitro, we examined proliferative and migratory behaviours as well as the underlying signalling mechanisms in VSMCs in response to high glucose treatment. In vivo, we induced diabetes in SD rats with streptozocin and established the common carotid artery balloon injury model. Suv39h1 was found to be both necessary and sufficient to promote VSMC proliferation and migration under high glucose conditions. We observed corresponding changes in intracellular signalling molecules including complement C3 and phosphor-ERK1/2. However, either up-regulating or down-regulating Suv39h1, phosphor-p38 level was not significantly affected. Consistently, Suv39h1 overexpression led to accelerated neointima formation, while knocking down Suv39h1 reduced it following carotid artery injury in diabetic rats. Using microarray analyses, we showed that altering the Suv39h1 level in vivo dramatically altered the expression of myriad genes mediating different biological processes and molecular function. This study reveals the novel role of Suv39h1 in VSMCs of diabetes and suggests its potential role as a therapeutic target in diabetic vascular injury.

12.
Zootaxa ; 4679(1): zootaxa.4679.1.6, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31715972

RESUMO

Sinibotia lani, a new botiid loach is described from the Zuojiang River, located in Guangxi Autonomous Region, China. The species differs from other members of Sinibotia by a combination of the following morphological characters: body depth 17.5-21.1% SL; snout length shorter than postorbital length of head; eye diameter 10.2-13.2% HL; interorbital width 16.0-18.6% HL; suborbital spine reaching or extending beyond postorbital margin of eye; lower lip with pair of fleshy button-like clusters of papillae; dorsal-fin origin opposite to pelvic-fin origin, pelvic fin not reaching anus; includes six dark vertical bars on the body. A key to the species of Sinibotia is provided.


Assuntos
Cipriniformes , Animais , China , Rios
13.
Zootaxa ; 4604(1): zootaxa.4604.1.6, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31717205

RESUMO

A new spined loach of the genus Cobitis Linnaeus is described from the Buquan River, located in Guangxi Zhuang Autonomous Region, China. The species differs from other members of Cobitis in China by a combination of morphological characters, none of them unique: body depth 14.3‒18.4% SL; lamina circularis long and knife-shaped; Gambetta zones present on the dorsolateral sides of the body (L1‒L5); 8‒11 large transverse elongated blotches on L5; 9‒12 large transverse elongated blotches on L1; maxillary barbels longer than eye diameter; 4‒5 narrow rows of dark spots on the caudal fin; caudal fin with 14 branched rays; a rectangular spot slightly smaller than eye diameter on the upper side of caudal fin base; and caudal-peduncle depth 79.5‒93.1% its length.


Assuntos
Besouros , Cipriniformes , Animais , China , Rios
14.
Plant J ; 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733118

RESUMO

Phosphorus (P) is an essential macronutrient required for plant development and production. The mechanisms regulating phosphate (Pi) uptake are well established, but the function of chloroplast Pi homeostasis are poorly understood in rice. PHT2;1 is one of the transporters/translocators mediating Pi import into chloroplasts. In this study, to gain insight into the role of OsPHT2;1-mediated stroma Pi, we analyzed OsPHT2;1 function in Pi utilization and photoprotection. Our results showed that OsPHT2;1 was induced by Pi starvation and light exposure. Cell-based assays showed that OsPHT2;1 localized to the chloroplast envelope and functioned as a low-affinity Pi transporter. The ospht2;1 had reduced Pi accumulation, plant growth and photosynthetic rates. Metabolite profiling revealed that 52.6% of the decreased metabolites in ospht2;1 plants were flavonoids, which was further confirmed by 40% lower content of total flavonoids compared to wild type. As a consequence, ospht2;1 plants were more sensitive to UV-B irradiation. Moreover, the content of phenylalanine, the precursor of flavonoids, was also reduced, and largely associated with the repressed expression of ADT1/MTR1. Furthermore, the ospht2;1 showed decreased grain yields at relatively high levels of UV-B irradiance. In summary, OsPHT2;1 functions as a chloroplast-localized low-affinity Pi transporter that mediates UV tolerance and rice yields in different latitudes.

15.
Zootaxa ; 4609(2): zootaxa.4609.2.3, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31717106

RESUMO

Amolops shuichengicus sp. nov., a new species of the A. mantzorum group is described from Guizhou, southwest China, on the basis of significant molecular divergences in 16S + CO1 genes and the combination of morphological characteristics: small body size, SVL 34.6-39.6 mm in adult males and 48.5-55.5 mm in adult females; dorsal skin relatively smooth; presence of vomerine teeth; presence of cream maxillary gland from lower edge of eye to the anterior of supratympanic fold; presence of supratympanic folds and glandular dorsolateral folds; tympanum indistinct; absence of a circummarginal groove on the disk of the first finger; presence of supernumerary tubercles below the base of fingers III and IV; absence of outer metatarsal tubercle and tarsal glands; males without vocal sacs. In addition, evidenced by the phylogenetic analyses in this study and literature data, we suggest that A. liangshanensis should be synonymized with A. loloensis and the records of A. marmoratus in Yunnan, China should be referred to A. afghanus. Following our proposal, the genus Amolops contains 57 species, with 32 recorded from China.


Assuntos
Anuros , Ranidae , Animais , Tamanho Corporal , China , Feminino , Masculino , Filogenia
16.
J Clin Sleep Med ; 15(11): 1621-1627, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739852

RESUMO

STUDY OBJECTIVES: The aim of this study was to investigate the association of bedtime with the prevalence of diabetes mellitus (DM) based on a large community-based population. METHODS: In total, 5,420 participants (2,574 males and 2,846 females; aged 63.5 ± 11.0 years) from the Sleep Heart Health Study database were selected in this study. Sleep habit was recorded based on a questionnaire administered to patients upon recruitment. Bedtime was categorized as 11:00 pm and before, 11:00 pm to 12:00 am, and 12:00 am and later in the current study. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) to determine the relationship between bedtime and the prevalence of DM. RESULTS: The distribution of weekday bedtime at 11:00 pm and before, 11:00 pm to 12:00 am, 12:00 am and later was observed in 3,316 participants (61.2%), 991 participants (18.3%), and 1,113 participants (20.5%), respectively. Meanwhile, individuals with weekday bedtime of 12:00 am and later had a higher prevalence of DM than those with bedtime at 11:00 pm to 12:00 am, and 11:00 pm and before (10.6% versus 5.7% versus 6.6%, respectively; P < .001). In the adjusted multivariate logistic regression model, bedtime at 12:00 am and later on a weekday was significantly associated DM prevalence (OR 1.446, 95% CI 1.107-1.888, P = .007). No significant association was found between weekend bedtime and DM. CONCLUSION: Late bedtime at 12:00 am and later on a weekday may be a risk factor for the prevalence of DM. Stable sleep timing leads to lower risk of DM deserves future exploration.

17.
Sensors (Basel) ; 19(21)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671917

RESUMO

In this paper, we propose a novel direction-of-arrival (DOA) estimation structure based on multiple-input multiple-output (MIMO) radar with colocated antennas, referred to as compressive measurement-based MIMO (CM-MIMO) radar, where the compressive sensing (CS) is employed to reduce the number of channels. Therefore, the system complexity and the computational burden are effectively reduced. It is noted that CS is used after the matched filters and that a measurement matrix with less rows than columns is multiplied with the received signals. As a result, the configurations of the transmit and receive antenna arrays are not affected by the CS and can be determined according to the practical requirements. To study the estimation performance, the Cramér-Rao bound (CRB) with respect to the DOAs of the proposed CM-MIMO radar is analyzed in this paper. The derived CRB expression is also suitable for the conventional MIMO radar by setting the measurement matrix as an identity matrix. Moreover, the CRB expression can work in the under-determined case, since the sum-difference coarray structure is considered. However, the random measurement matrix leads to high information loss, thus compromising the estimation performance. To overcome this problem, we consider that the a prior probability distribution of the DOAs associated with the targets can be obtained in many scenarios and an optimization approach for the measurement matrix is proposed in this paper, where the maximum mutual information criterion is adopted. The superiority of the proposed structure is validated by numerical simulations.

18.
Stem Cell Reports ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31708477

RESUMO

In contrast to conventional human pluripotent stem cells (hPSCs) that are related to post-implantation embryo stages, naive hPSCs exhibit features of pre-implantation epiblast. Naive hPSCs are established by resetting conventional hPSCs, or are derived from dissociated embryo inner cell masses. Here we investigate conditions for transgene-free reprogramming of human somatic cells to naive pluripotency. We find that Wnt inhibition promotes RNA-mediated induction of naive pluripotency. We demonstrate application to independent human fibroblast cultures and endothelial progenitor cells. We show that induced naive hPSCs can be clonally expanded with a diploid karyotype and undergo somatic lineage differentiation following formative transition. Induced naive hPSC lines exhibit distinctive surface marker, transcriptome, and methylome properties of naive epiblast identity. This system for efficient, facile, and reliable induction of transgene-free naive hPSCs offers a robust platform, both for delineation of human reprogramming trajectories and for evaluating the attributes of isogenic naive versus conventional hPSCs.

20.
J Fish Biol ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31782180

RESUMO

A new loach Oreonectes guilinensis sp. nov. is described from Guangxi Zhuang Autonomous Region, China. It is the second surface-dwelling fish identified in the genus Oreonectes after the type species Oreonectes platycephalus. This new species can be distinguished from other species within the genus by the combination of the following features: a round caudal fin, 13-14 branched rays, an incomplete lateral line with 4-6 pores, a short pelvic fin located some distance from the anus, a scale-covered body, a stout build (body width 14.0%-16.7% of standard length), a posterior chamber of well-developed airbladder and a yellowish-brown body with a lateral dark brown strip. The maximum likelihood phylogenetic analysis based on cytb gene recovered this new species in a well-supported clade with the type species O. platycephalus, sister to the Lefua clade. Morphological comparisons as well as our phylogenetic tree support Oreonectes shuilongensis, Oreonectes daqikongensis, Oreonectes jiarongensis as species of Troglonectes. Based on our results there are 6 valid species in the genus Oreonectes.

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