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1.
BMC Surg ; 24(1): 53, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355459

RESUMO

BACKGROUND: Breast cancer surgeries involving MS-TRAM/DIEP breast reconstruction has traditionally been collaborative efforts between breast surgeons and plastic surgeons. However, in our institution, this procedure is performed by dual-trained breast surgeons who are proficient in both breast surgery and MS-TRAM/DIEP breast reconstruction. This study aims to provide insights into the learning curve associated with this surgical approach. MATERIALS AND METHODS: We included eligible breast cancer patients who underwent MS-TRAM/DIEP breast reconstruction by dual-trained breast surgeons between 2015 and 2020 at our institution. We present the learning curve of this surgical approach, with a focus on determining factors affecting flap harvesting time, surgery time, and ischemic time. Additionally, we assessed the surgical complication rates. RESULTS: A total of 147 eligible patients were enrolled in this study. Notably, after 30 cases, a statistically significant reduction of 1.7 h in surgery time and 21 min in ischemic time was achieved, signifying the attainment of a plateau in the learning curve. And the major and minor complications were comparable between the early and after 30 cases. CONCLUSION: This study explores the learning curve and feasibility experienced by dual-trained breast surgeons in performing MS-TRAM/DIEP breast reconstruction. TRIAL REGISTRATION: NCT05560633.


Assuntos
Neoplasias da Mama , Mamoplastia , Cirurgiões , Humanos , Feminino , Curva de Aprendizado , Complicações Pós-Operatórias/etiologia , Mamoplastia/métodos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/complicações , Estudos Retrospectivos
2.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33971669

RESUMO

A large number of genetic variations have been identified to be associated with Alzheimer's disease (AD) and related quantitative traits. However, majority of existing studies focused on single types of omics data, lacking the power of generating a community including multi-omic markers and their functional connections. Because of this, the immense value of multi-omics data on AD has attracted much attention. Leveraging genomic, transcriptomic and proteomic data, and their backbone network through functional relations, we proposed a modularity-constrained logistic regression model to mine the association between disease status and a group of functionally connected multi-omic features, i.e. single-nucleotide polymorphisms (SNPs), genes and proteins. This new model was applied to the real data collected from the frontal cortex tissue in the Religious Orders Study and Memory and Aging Project cohort. Compared with other state-of-art methods, it provided overall the best prediction performance during cross-validation. This new method helped identify a group of densely connected SNPs, genes and proteins predictive of AD status. These SNPs are mostly expression quantitative trait loci in the frontal region. Brain-wide gene expression profile of these genes and proteins were highly correlated with the brain activation map of 'vision', a brain function partly controlled by frontal cortex. These genes and proteins were also found to be associated with the amyloid deposition, cortical volume and average thickness of frontal regions. Taken together, these results suggested a potential pathway underlying the development of AD from SNPs to gene expression, protein expression and ultimately brain functional and structural changes.


Assuntos
Doença de Alzheimer/genética , Bases de Dados de Ácidos Nucleicos , Genômica , Polimorfismo de Nucleotídeo Único , Transcriptoma , Doença de Alzheimer/metabolismo , Estudo de Associação Genômica Ampla , Humanos
3.
Bioinformatics ; 38(4): 1165-1167, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34694378

RESUMO

MOTIVATION: The increasing availability of multi-omic data has enabled the discovery of disease biomarkers in different scales. Understanding the functional interaction between multi-omic biomarkers is becoming increasingly important due to its great potential for providing insights of the underlying molecular mechanism. RESULTS: Leveraging multiple biological network databases, we integrated the relationship between single nucleotide polymorphisms (SNPs), genes/proteins and metabolites, and developed an R package Multi-omic Network Explorer Tool (MoNET) for multi-omic network analysis. This new tool enables users to not only track down the interaction of SNPs/genes with metabolome level, but also trace back for the potential risk variants/regulators given altered genes/metabolites. MoNET is expected to advance our understanding of the multi-omic findings by unveiling their transomic interactions and is likely to generate new hypotheses for further validation. AVAILABILITY AND IMPLEMENTATION: The MoNET package is freely available on https://github.com/JW-Yan/MONET. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Multiômica , Software , Bases de Dados Factuais , Gerenciamento de Dados , Biomarcadores
4.
Int Orthop ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733064

RESUMO

PURPOSE: Acute compartment syndrome (ACS) is an urgent, critical condition that requires immediate fasciotomy once diagnosed. Traditionally, fasciotomy of the forearms and lower leg involves one or two long approaches. Our previous study demonstrated that mini approaches fasciotomy was an effective method to treat ACS. This study is aimed at further evaluating the limb functions and complications of mini approaches combined with vacuum sealing drainage (VSD) for treating ACS caused by fractures in the forearms and lower legs. METHODS: This was a retrospective cross-sectional study, and after applying the inclusion and exclusion criteria, we reviewed 126 children who underwent mini treatment approaches for ACS from Jan 2008 to Jan 2022. The selected patients were divided into two groups: group A (ACS group; 58 patients aged 7.77±3.45 years) and group B (ACS combined with VSD; 68 patients aged 7.17±3.55 years). Patients' clinical data were collected. The patients were followed up, and muscle function in the forearms and lower legs was evaluated. RESULTS: The overall incidence of lower legs and forearms ACS was 126/29642 (0.425%). The most common mechanisms of injury were fractures of the forearm (39/74, 52.7%), supracondylar humerus (31/74 41.9%), and elbow (4/74, 5.4%), while those for the lower legs were fractures of the proximal tibia (19/52, 36.5%), midshaft of tibia (25/52, 48.1%), and distal tibia (7/52, 13.5%). According to Flynn's assessment, no significant difference was observed between the two groups (p=0.151). However, the two groups showed significant differences in the hospitalization time (p=0.002) and incision infection rate (0.043). CONCLUSIONS: Mini approaches fasciotomy combined with VSD is an effective and safe method to treat ACS of the forearms and lower legs caused by fractures in children. This method involves a single-stage surgery and is associated with shorter hospitalization time and incision infection.

5.
Trends Genet ; 35(5): 371-382, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30922659

RESUMO

Advances in high-throughput genotyping and next-generation sequencing (NGS) coupled with larger sample sizes brings the realization of precision medicine closer than ever. Polygenic approaches incorporating the aggregate influence of multiple genetic variants can contribute to a better understanding of the genetic architecture of many complex diseases and facilitate patient stratification. This review addresses polygenic concepts, methodological developments, hypotheses, and key issues in study design. Polygenic risk scores (PRSs) have been applied to many complex diseases and here we focus on Alzheimer's disease (AD) as a primary exemplar. This review was designed to serve as a starting point for investigators wishing to use PRSs in their research and those interested in enhancing clinical study designs through enrichment strategies.


Assuntos
Doença de Alzheimer/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Herança Multifatorial/genética , Doença de Alzheimer/diagnóstico , Progressão da Doença , Humanos , Desequilíbrio de Ligação , Fenótipo , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais
6.
BMC Gastroenterol ; 22(1): 165, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35382743

RESUMO

BACKGROUND: Anorectal malignant melanoma (ARMM) and low rectal adenocarcinoma (LRAC) have some similarities in clinical behaviors, histopathological characteristics and ultrasonographic findings, diagnostic errors are common. By comparing the transrectally ultrasonographic features between the two tumors, we propose to provide more possibilities in differentiating them. METHODS: The data of 9 ARMMs and 27 age- and gender-matched LRACs (the lower margin below the peritoneal reflection) in West China Hospital Sichuan University between April 2008 and July 2019 were retrospectively reviewed. The ultrasonic features between the two groups were compared. RESULTS: Transrectal ultrasonography (TRUS) showed that the length of ARMM was shorter than that of LRAC (28.22 ± 12.29 mm vs. 40.22 ± 15.16 mm), and ARMM had a lower position than that of LRAC (the distance to anal verge was 50.78 ± 11.70 vs. 63.81 ± 18.73 mm). Unlike LRAC, the majority of ARMM in our study was confined to the intestinal mucosa/submucosa (66.67/25.93%) (P < 0.05). CONCLUSIONS: Based on the data of our study, several ultrasonographic findings (length, invasion depth, and position) of ARMM were significantly different from LRAC. Accordingly, more attention should be paid to masses at anorectal junction with lower position, shorter length, and shallower infiltration depth. Instead of the most common tumor, LRAC, ARMM should be taken into account to avoid a misdiagnosis, which will result in a poorer prognosis.


Assuntos
Adenocarcinoma , Melanoma , Neoplasias Retais , Adenocarcinoma/diagnóstico por imagem , Humanos , Melanoma/diagnóstico por imagem , Melanoma/patologia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Estudos Retrospectivos , Ultrassonografia
7.
Environ Res ; 204(Pt C): 112321, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34748777

RESUMO

BACKGROUND: Pulmonary embolism (PE) is a life-threatening condition. Few studies have evaluated the relationship between air pollution and PE, and these results have been inconsistent. Therefore, our study aimed to investigate the association between air pollutant exposure and the risk of hospitalization due to PE. MATERIALS AND METHODS: Daily PE admissions, meteorological data, and ambient pollution data from January 1, 2015, to December 31, 2018, were collected in Beijing. A quasi-Poisson regression model combined with time-stratified case-crossover design and a distributed lag nonlinear model was used to determine the effect of air pollutant exposure on PE admission. To examine the stability of air pollutants' effects, multi-pollutant analyses were performed. Stratified analyses by age and sex were further conducted. RESULTS: There were 5060 PE admissions during the study period, with an estimated incidence of 6.5 per 100,000. PM2.5, PM10, SO2, O3 and CO exposures were significantly associated with elevated risk of PE hospitalization. The highest cumulative risks were observed at a lag of 0-28 days for PM2.5 (relative risk [RR] = 1.056, 95% confidence intervals [CI]: 1.015-1.098), PM10 (RR = 1.042, 95%CI: 1.010-1.075), and CO (RR = 1.466, 95%CI: 1.127-1.906), at a lag of 0-27 days for SO2 (RR = 1.674, 95%CI: 1.200-2.335), and at a lag of 0-4 days for O3 (RR = 1.019, 95%CI: 1.001-1.038). All associations mentioned above except O3 remained significant in multi-pollutant models. Stratified analyses showed that women and those aged ≥65 years people were more sensitive to PM10 and CO exposure than men and those aged <65 years. The effect of PM2.5 exposure was statistically significant in all subgroups. CONCLUSIONS: Exposure to PM2.5, PM10, SO2, and CO showed a positive association with PE hospitalization. High-risk PE groups should take special precautions on days with poor air quality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Embolia Pulmonar , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Pequim/epidemiologia , China/epidemiologia , Estudos Cross-Over , Exposição Ambiental/análise , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Material Particulado/análise , Material Particulado/toxicidade
8.
Sensors (Basel) ; 22(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36015808

RESUMO

Rust is a common disease in wheat that significantly impacts its growth and yield. Stem rust and leaf rust of wheat are difficult to distinguish, and manual detection is time-consuming. With the aim of improving this situation, this study proposes a method for identifying wheat rust based on ensemble learning (WR-EL). The WR-EL method extracts and integrates multiple convolutional neural network (CNN) models, namely VGG, ResNet 101, ResNet 152, DenseNet 169, and DenseNet 201, based on bagging, snapshot ensembling, and the stochastic gradient descent with warm restarts (SGDR) algorithm. The identification results of the WR-EL method were compared to those of five individual CNN models. The results show that the identification accuracy increases by 32%, 19%, 15%, 11%, and 8%. Additionally, we proposed the SGDR-S algorithm, which improved the f1 scores of healthy wheat, stem rust wheat and leaf rust wheat by 2%, 3% and 2% compared to the SGDR algorithm, respectively. This method can more accurately identify wheat rust disease and can be implemented as a timely prevention and control measure, which can not only prevent economic losses caused by the disease, but also improve the yield and quality of wheat.


Assuntos
Basidiomycota , Triticum , Aprendizado de Máquina , Doenças das Plantas
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(5): 897-908, 2022 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-36310478

RESUMO

Cranial defects may result from clinical brain tumor surgery or accidental trauma. The defect skulls require hand-designed skull implants to repair. The edge of the skull implant needs to be accurately matched to the boundary of the skull wound with various defects. For the manual design of cranial implants, it is time-consuming and technically demanding, and the accuracy is low. Therefore, an informer residual attention U-Net (IRA-Unet) for the automatic design of three-dimensional (3D) skull implants was proposed in this paper. Informer was applied from the field of natural language processing to the field of computer vision for attention extraction. Informer attention can extract attention and make the model focus more on the location of the skull defect. Informer attention can also reduce the computation and parameter count from N 2 to log( N). Furthermore,the informer residual attention is constructed. The informer attention and the residual are combined and placed in the position of the model close to the output layer. Thus, the model can select and synthesize the global receptive field and local information to improve the model accuracy and speed up the model convergence. In this paper, the open data set of the AutoImplant 2020 was used for training and testing, and the effects of direct and indirect acquisition of skull implants on the results were compared and analyzed in the experimental part. The experimental results show that the performance of the model is robust on the test set of 110 cases fromAutoImplant 2020. The Dice coefficient and Hausdorff distance are 0.940 4 and 3.686 6, respectively. The proposed model reduces the resources required to run the model while maintaining the accuracy of the cranial implant shape, and effectively assists the surgeon in automating the design of efficient cranial repair, thereby improving the quality of the patient's postoperative recovery.


Assuntos
Desenho Assistido por Computador , Crânio , Humanos , Crânio/cirurgia , Próteses e Implantes , Cabeça
10.
Bioinformatics ; 36(8): 2554-2560, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31860065

RESUMO

MOTIVATION: Brain imaging genetics aims to reveal genetic effects on brain phenotypes, where most studies examine phenotypes defined on anatomical or functional regions of interest (ROIs) given their biologically meaningful interpretation and modest dimensionality compared with voxelwise approaches. Typical ROI-level measures used in these studies are summary statistics from voxelwise measures in the region, without making full use of individual voxel signals. RESULTS: In this article, we propose a flexible and powerful framework for mining regional imaging genetic associations via voxelwise enrichment analysis, which embraces the collective effect of weak voxel-level signals and integrates brain anatomical annotation information. Our proposed method achieves three goals at the same time: (i) increase the statistical power by substantially reducing the burden of multiple comparison correction; (ii) employ brain annotation information to enable biologically meaningful interpretation and (iii) make full use of fine-grained voxelwise signals. We demonstrate our method on an imaging genetic analysis using data from the Alzheimer's Disease Neuroimaging Initiative, where we assess the collective regional genetic effects of voxelwise FDG-positron emission tomography measures between 116 ROIs and 565 373 single-nucleotide polymorphisms. Compared with traditional ROI-wise and voxelwise approaches, our method identified 2946 novel imaging genetic associations in addition to 33 ones overlapping with the two benchmark methods. In particular, two newly reported variants were further supported by transcriptome evidences from region-specific expression analysis. This demonstrates the promise of the proposed method as a flexible and powerful framework for exploring imaging genetic effects on the brain. AVAILABILITY AND IMPLEMENTATION: The R code and sample data are freely available at https://github.com/lshen/RIGEA. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Doença de Alzheimer , Neuroimagem , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Encéfalo/diagnóstico por imagem , Humanos , Polimorfismo de Nucleotídeo Único , Tomografia por Emissão de Pósitrons
11.
Sensors (Basel) ; 21(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34640873

RESUMO

Yellow rust is a disease with a wide range that causes great damage to wheat. The traditional method of manually identifying wheat yellow rust is very inefficient. To improve this situation, this study proposed a deep-learning-based method for identifying wheat yellow rust from unmanned aerial vehicle (UAV) images. The method was based on the pyramid scene parsing network (PSPNet) semantic segmentation model to classify healthy wheat, yellow rust wheat, and bare soil in small-scale UAV images, and to investigate the spatial generalization of the model. In addition, it was proposed to use the high-accuracy classification results of traditional algorithms as weak samples for wheat yellow rust identification. The recognition accuracy of the PSPNet model in this study reached 98%. On this basis, this study used the trained semantic segmentation model to recognize another wheat field. The results showed that the method had certain generalization ability, and its accuracy reached 98%. In addition, the high-accuracy classification result of a support vector machine was used as a weak label by weak supervision, which better solved the labeling problem of large-size images, and the final recognition accuracy reached 94%. Therefore, the present study method facilitated timely control measures to reduce economic losses.


Assuntos
Basidiomycota , Aprendizado Profundo , Doenças das Plantas , Máquina de Vetores de Suporte , Triticum
12.
BMC Genomics ; 21(Suppl 11): 896, 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33372590

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified many individual genes associated with brain imaging quantitative traits (QTs) in Alzheimer's disease (AD). However single marker level association discovery may not be able to address the underlying biological interactions with disease mechanism. RESULTS: In this paper, we used the MGAS (Multivariate Gene-based Association test by extended Simes procedure) tool to perform multivariate GWAS on eight AD-relevant subcortical imaging measures. We conducted multiple iPINBPA (integrative Protein-Interaction-Network-Based Pathway Analysis) network analyses on MGAS findings using protein-protein interaction (PPI) data, and identified five Consensus Modules (CMs) from the PPI network. Functional annotation and network analysis were performed on the identified CMs. The MGAS yielded significant hits within APOE, TOMM40 and APOC1 genes, which were known AD risk factors, as well as a few new genes such as LAMA1, XYLB, HSD17B7P2, and NPEPL1. The identified five CMs were enriched by biological processes related to disorders such as Alzheimer's disease, Legionellosis, Pertussis, and Serotonergic synapse. CONCLUSIONS: The statistical power of coupling MGAS with iPINBPA was higher than traditional GWAS method, and yielded new findings that were missed by GWAS. This study provides novel insights into the molecular mechanism of Alzheimer's Disease and will be of value to novel gene discovery and functional genomic studies.


Assuntos
Doença de Alzheimer , Estudo de Associação Genômica Ampla , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Encéfalo/diagnóstico por imagem , Predisposição Genética para Doença , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único , Mapas de Interação de Proteínas
13.
Anal Chem ; 92(8): 5960-5968, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32202765

RESUMO

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a family of recently discovered lipids with important physiological functions in mammals and plants. However, low detection sensitivity in negative ionization mode mass spectrometry makes low-abundance FAHFA challenging to analyze. A 2-dimethylaminoethylamine (DMED) based chemical derivatization strategy was recently reported to improve the MS sensitivity of FAHFAs by labeling FAHFAs with a positively ionizable tertiary amine group. To facilitate reliable, high-throughput, and automatic annotation of these compounds, a DMED-FAHFA in silico library containing 4290 high-resolution tandem mass spectra covering 264 different FAHFA classes was developed. The construction of the library was based on the heuristic information from MS/MS fragmentation patterns of DMED-FAHFA authentic standards, and then, the patterns were applied to computer-generated DMED-FAHFAs. The developed DMED-FAHFA in silico library was demonstrated to be compatible with library search software NIST MS Search and the LC-MS/MS data processing tool MS-DIAL to guarantee high-throughput and automatic annotations. Applying the in silico library in Arabidopsis thaliana samples for profiling FAHFAs by high-resolution LC-MS/MS enabled the annotation of 19 DMED-FAHFAs from 16 families, including 3 novel compounds. Using the in silico library largely decreased the false-positive annotation rate in comparison to low-resolution LC-MS/MS. The developed library, MS/MS spectra, and development templates are freely available for commercial and noncommercial use at https://zenodo.org/record/3606905.


Assuntos
Ésteres/análise , Etilaminas/química , Ácidos Graxos/análise , Estrutura Molecular , Espectrometria de Massas em Tandem
14.
Brief Bioinform ; 19(6): 1370-1381, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-28679163

RESUMO

In the past decade, significant progress has been made in complex disease research across multiple omics layers from genome, transcriptome and proteome to metabolome. There is an increasing awareness of the importance of biological interconnections, and much success has been achieved using systems biology approaches. However, because of the typical focus on one single omics layer at a time, existing systems biology findings explain only a modest portion of complex disease. Recent advances in multi-omics data collection and sharing present us new opportunities for studying complex diseases in a more comprehensive fashion, and yet simultaneously create new challenges considering the unprecedented data dimensionality and diversity. Here, our goal is to review extant and emerging network approaches that can be applied across multiple biological layers to facilitate a more comprehensive and integrative multilayered omics analysis of complex diseases.


Assuntos
Genômica , Proteômica , Biologia de Sistemas , Transcriptoma , Mineração de Dados , Epistasia Genética , Aprendizado de Máquina
15.
Sensors (Basel) ; 20(20)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096671

RESUMO

Network security is a crucial challenge facing Internet-of-Things (IoT) systems worldwide, which leads to serious safety alarms and great economic loss. This paper studies the problem of malicious interdicting network exploitation of IoT systems that are modeled as a bi-layer logical-physical network. In this problem, a virtual attack takes place at the logical layer (the layer of Things), while the physical layer (the layer of Internet) provides concrete support for the attack. In the interdiction problem, the attacker attempts to access a target node on the logical layer with minimal communication cost, but the defender can strategically interdict some key edges on the physical layer given a certain budget of interdiction resources. This setting generalizes the classic single-layer shortest-path network interdiction problem, but brings in nonlinear objective functions, which are notoriously challenging to optimize. We reformulate the model and apply Benders decomposition process to solve this problem. A layer-mapping module is introduced to improve the decomposition algorithm and a random-search process is proposed to accelerate the convergence. Extensive numerical experiments demonstrate the computational efficiency of our methods.

16.
Sensors (Basel) ; 20(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977569

RESUMO

In order to improve the performance of the large divergence angle mid-infrared source in gas sensing, this paper aims at developing a methane (CH4) sensor with non-dispersive infrared (NDIR) technology using a compact pentahedron gas-cell. A paraboloid concentrator, two biconvex lenses and five planar mirrors were used to set up the pentahedron structure. The gas cell is endowed with a 170 mm optical path length with a volume of 19.8 mL. The mathematical model of the cross-section and the three-dimension spiral structure of the pentahedron gas-cell were established. The gas-cell was integrated with a mid-infrared light source and a detector as the optical part of the sensor. Concerning the electrical part, a STM32F429 was employed as a microcontroller to generate the driving signal for the IR source, and the signal from the detector was sampled by an analog-to-digital converter. A static volumetric method was employed for the experimental setup, and 20 different concentration CH4 samples were prepared to study the sensor's evaluation, which revealed a 1σ detection limit of 2.96 parts-per-million (ppm) with a 43 s averaging time.

17.
BMC Genomics ; 20(Suppl 1): 80, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712512

RESUMO

The sixth International Conference on Intelligent Biology and Medicine (ICIBM) took place in Los Angeles, California, USA on June 10-12, 2018. This conference featured eleven regular scientific sessions, four tutorials, one poster session, four keynote talks, and four eminent scholar talks. The scientific program covered a wide range of topics from bench to bedside, including 3D Genome Organization, reconstruction of large scale evolution of genomes and gene functions, artificial intelligence in biological and biomedical fields, and precision medicine. Both method development and application in genomic research continued to be a main component in the conference, including studies on genetic variants, regulation of transcription, genetic-epigenetic interaction at both single cell and tissue level and artificial intelligence. Here, we write a summary of the conference and also briefly introduce the four high quality papers selected to be published in BMC Genomics that cover novel methodology development or innovative data analysis.


Assuntos
Inteligência Artificial , Biologia , Medicina , Biologia/métodos , Humanos , Medicina/métodos
18.
Bioinformatics ; 34(17): i866-i874, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423101

RESUMO

Motivation: The identification of quantitative trait loci (QTL) is critical to the study of causal relationships between genetic variations and disease abnormalities. We focus on identifying the QTLs associated to the brain endophenotypes in imaging genomics study for Alzheimer's Disease (AD). Existing research works mainly depict the association between single nucleotide polymorphisms (SNPs) and the brain endophenotypes via the linear methods, which may introduce high bias due to the simplicity of the models. Since the influence of QTLs on brain endophenotypes is quite complex, it is desired to design the appropriate non-linear models to investigate the associations of genotypes and endophenotypes. Results: In this paper, we propose a new additive model to learn the non-linear associations between SNPs and brain endophenotypes in Alzheimer's disease. Our model can be flexibly employed to explain the non-linear influence of QTLs, thus is more adaptive for the complex distribution of the high-throughput biological data. Meanwhile, as an important computational learning theory contribution, we provide the generalization error analysis for the proposed approach. Unlike most previous theoretical analysis under independent and identically distributed samples assumption, our error bound is based on m-dependent observations, which is more appropriate for the high-throughput and noisy biological data. Experiments on the data from Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort demonstrate the promising performance of our approach for identifying biological meaningful SNPs. Availability and implementation: An executable is available at https://github.com/littleq1991/additive_FNNRW.


Assuntos
Encéfalo , Locos de Características Quantitativas , Doença de Alzheimer/genética , Encéfalo/metabolismo , Endofenótipos , Genótipo , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único , Software
19.
Bioinformatics ; 34(2): 278-285, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28968815

RESUMO

MOTIVATION: Brain imaging genetics, which studies the linkage between genetic variations and structural or functional measures of the human brain, has become increasingly important in recent years. Discovering the bi-multivariate relationship between genetic markers such as single-nucleotide polymorphisms (SNPs) and neuroimaging quantitative traits (QTs) is one major task in imaging genetics. Sparse Canonical Correlation Analysis (SCCA) has been a popular technique in this area for its powerful capability in identifying bi-multivariate relationships coupled with feature selection. The existing SCCA methods impose either the ℓ1-norm or its variants to induce sparsity. The ℓ0-norm penalty is a perfect sparsity-inducing tool which, however, is an NP-hard problem. RESULTS: In this paper, we propose the truncated ℓ1-norm penalized SCCA to improve the performance and effectiveness of the ℓ1-norm based SCCA methods. Besides, we propose an efficient optimization algorithms to solve this novel SCCA problem. The proposed method is an adaptive shrinkage method via tuning τ. It can avoid the time intensive parameter tuning if given a reasonable small τ. Furthermore, we extend it to the truncated group-lasso (TGL), and propose TGL-SCCA model to improve the group-lasso-based SCCA methods. The experimental results, compared with four benchmark methods, show that our SCCA methods identify better or similar correlation coefficients, and better canonical loading profiles than the competing methods. This demonstrates the effectiveness and efficiency of our methods in discovering interesting imaging genetic associations. AVAILABILITY AND IMPLEMENTATION: The Matlab code and sample data are freely available at http://www.iu.edu/∼shenlab/tools/tlpscca/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

20.
Anal Chem ; 90(16): 10056-10063, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30052436

RESUMO

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a new class of lipid mediators with promising anti-diabetic and anti-inflammatory properties. Comprehensive screening and identification of FAHFAs in biological samples would be beneficial to the discovery of new FAHFAs and enable greater understanding of their biological functions. Here, we report the comprehensive screening of FAHFAs in rice and  Arabidopsis thaliana by chemical isotope labeling-assisted liquid chromatography-mass spectrometry (CIL-LC-MS). Multiple reaction monitoring (MRM) was used for screening of FAHFAs. With the proposed method, we detected 49 potential FAHFA families, including 262 regioisomers, in tissues of rice and Arabidopsis thaliana, which greatly extends our knowledge of known FAHFAs. In addition, we proposed a strategy to identify FAHFA regioisomers based on their retention on a reversed-phase LC column. Using the proposed identification strategy, we identified 71 regioisomers from 11 FAHFA families based on commercial standards and characteristic chromatographic retention behaviors. The screening technique could allow for the discovery of new FAHFAs in biological samples. The new FAHFAs identified in this work will contribute to the in-depth study of the functions of FAHFAs.


Assuntos
Arabidopsis/química , Cromatografia Líquida/métodos , Ácidos Graxos/análise , Oryza/química , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos/química , Isomerismo , Marcação por Isótopo , Folhas de Planta/química
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