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1.
Front Bioeng Biotechnol ; 12: 1392575, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933536

RESUMO

Stem cell-derived islets (SC-islets) are not only an unlimited source for cell-based therapy of type 1 diabetes but have also emerged as an attractive material for modeling diabetes and conducting screening for treatment options. Prior to SC-islets becoming the established standard for disease modeling and drug development, it is essential to understand their response to various nutrient sources in vitro. This study demonstrates an enhanced efficiency of pancreatic endocrine cell differentiation through the incorporation of WNT signaling inhibition following the definitive endoderm stage. We have identified a tri-hormonal cell population within SC-islets, which undergoes reduction concurrent with the emergence of elevated numbers of glucagon-positive cells during extended in vitro culture. Over a 6-week period of in vitro culture, the SC-islets consistently demonstrated robust insulin secretion in response to glucose stimulation. Moreover, they manifested diverse reactivity patterns when exposed to distinct nutrient sources and exhibited deviant glycolytic metabolic characteristics in comparison to human primary islets. Although the SC-islets demonstrated an aberrant glucose metabolism trafficking, the evaluation of a potential antidiabetic drug, pyruvate kinase agonist known as TEPP46, significantly improved in vitro insulin secretion of SC-islets. Overall, this study provided cell identity dynamics investigation of SC-islets during prolonged culturing in vitro, and insights into insulin secretagogues. Associated advantages and limitations were discussed when employing SC-islets for disease modeling.

2.
Transpl Int ; 37: 11900, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38304198

RESUMO

The generation of insulin-producing cells from human-induced pluripotent stem cells holds great potential for diabetes modeling and treatment. However, existing protocols typically involve incubating cells with un-physiologically high concentrations of glucose, which often fail to generate fully functional IPCs. Here, we investigated the influence of high (20 mM) versus low (5.5 mM) glucose concentrations on IPCs differentiation in three hiPSC lines. In two hiPSC lines that were unable to differentiate to IPCs sufficiently, we found that high glucose during differentiation leads to a shortage of NKX6.1+ cells that have co-expression with PDX1 due to insufficient NKX6.1 gene activation, thus further reducing differentiation efficiency. Furthermore, high glucose during differentiation weakened mitochondrial respiration ability. In the third iPSC line, which is IPC differentiation amenable, glucose concentrations did not affect the PDX1/NKX6.1 expression and differentiation efficiency. In addition, glucose-stimulated insulin secretion was only seen in the differentiation under a high glucose condition. These IPCs have higher KATP channel activity and were linked to sufficient ABCC8 gene expression under a high glucose condition. These data suggest high glucose concentration during IPC differentiation is necessary to generate functional IPCs. However, in cell lines that were IPC differentiation unamenable, high glucose could worsen the situation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células Secretoras de Insulina , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/metabolismo , Diferenciação Celular , Glucose/farmacologia , Glucose/metabolismo
3.
Adv Healthc Mater ; 13(13): e2303785, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38221504

RESUMO

Type 2 diabetes mellitus (T2DM), obesity, and metabolic dysfunction-associated steatotic liver disease (MASLD) are epidemiologically correlated disorders with a worldwide growing prevalence. While the mechanisms leading to the onset and development of these conditions are not fully understood, predictive tissue representations for studying the coordinated interactions between central organs that regulate energy metabolism, particularly the liver and pancreatic islets, are needed. Here, a dual pump-less recirculating organ-on-chip platform that combines human pluripotent stem cell (sc)-derived sc-liver and sc-islet organoids is presented. The platform reproduces key aspects of the metabolic cross-talk between both organs, including glucose levels and selected hormones, and supports the viability and functionality of both sc-islet and sc-liver organoids while preserving a reduced release of pro-inflammatory cytokines. In a model of metabolic disruption in response to treatment with high lipids and fructose, sc-liver organoids exhibit hallmarks of steatosis and insulin resistance, while sc-islets produce pro-inflammatory cytokines on-chip. Finally, the platform reproduces known effects of anti-diabetic drugs on-chip. Taken together, the platform provides a basis for functional studies of obesity, T2DM, and MASLD on-chip, as well as for testing potential therapeutic interventions.


Assuntos
Ilhotas Pancreáticas , Dispositivos Lab-On-A-Chip , Fígado , Organoides , Humanos , Fígado/metabolismo , Organoides/metabolismo , Ilhotas Pancreáticas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Glucose/metabolismo
4.
J Chromatogr A ; 1717: 464669, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38278130

RESUMO

Organoids are 3D cell cultures with microanatomies mimicking aspects of real organs, useful for e.g. animal-free studies of development, disease, and drug discovery. The cell medium of organoid models of Langerhans islets, regulating blood glucose levels by insulin secretion, can be analyzed by liquid chromatography-mass spectrometry (LC-MS). However, organoid medium complexity is a major challenge, as matrix interferences can reduce sensitivity and selectivity, even with optimized LC-MS conditions. By applying preparative agarose gel electrophoresis-electrodialysis (PGE-ED), we were able to decrease the cell medium background signal, allowing for reduced interferences affecting LC-MS analysis of human insulin.


Assuntos
Insulina , Espectrometria de Massa com Cromatografia Líquida , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Organoides , Eletroforese em Gel de Ágar
5.
Open Life Sci ; 18(1): 20220766, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045486

RESUMO

Albumin and prealbumin serve as vital markers reflecting hepatic synthesis activity and overall body nutrient status. Hypoproteinemia can result from various etiological factors, with reduced blood inflow into the liver due to portal vein thrombosis being one such cause. However, literature addressing this specific association remains limited. This report presents an atypical case of malnutrition involving a patient who experienced prolonged hypoproteinemia attributable to a gradual decline in hepatic blood perfusion caused by progressive portal thrombosis and cavernous transformation of the portal vein (CTPV). The case encompasses an in-depth analysis of the factors contributing to undernutrition, the etiology and diagnosis of hypoproteinemia, and its clinical implications. Vigilance for the presence of hypoproteinemia is essential in the management of patients afflicted by progressive portal vein thrombosis complicated by CTPV. Timely and effective interventions aimed at rectifying hypoproteinemia can significantly enhance clinical outcomes. Moreover, reduced hepatic blood flow should be considered a plausible underlying cause in cases of unexplained hypoproteinemia, warranting thorough evaluation. This case underscores the importance of recognizing the intricate interplay between hepatic vascular pathology and protein homeostasis in clinical practice.

6.
Electrophoresis ; 44(21-22): 1682-1697, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37574258

RESUMO

For studying stem cell-derived islet organoids (SC-islets) in an organ-on-chip (OoC) platform, we have developed a reversed-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) method allowing for simultaneous determination of insulin, somatostatin-14, and glucagon, with improved matrix robustness compared to earlier methodology. Combining phenyl/hexyl-C18 separations using 2.1 mm inner diameter LC columns and triple quadrupole mass spectrometry, identification and quantification were secured with negligible variance in retention time and quantifier/qualifier ratios, negligible levels of carryover (<2%), and sufficient precision (±10% RSD) and accuracy (±15% relative error) with and without use of an internal standard. The obtained lower limits of quantification were 0.2 µg/L for human insulin, 0.1 µg/L for somatostatin-14, and 0.05 µg/L for glucagon. The here-developed RPLC-MS/MS method showed that the SC-islets have an insulin response dependent on glucose concentration, and the SC-islets produce and release somatostatin-14 and glucagon. The RPLC-MS/MS method for these peptide hormones was compatible with an unfiltered offline sample collection from SC-islets cultivated on a pumpless, recirculating OoC (rOoC) platform. The SC-islets background secretion of insulin was not significantly different on the rOoC device compared to a standard cell culture well-plate. Taken together, RPLC-MS/MS method is well suited for multi-hormone measurements of SC-islets on an OoC platform.


Assuntos
Glucagon , Ilhotas Pancreáticas , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Glucose , Ilhotas Pancreáticas/fisiologia , Insulina , Peptídeos , Somatostatina , Organoides , Células-Tronco
7.
Front Bioeng Biotechnol ; 11: 1223737, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37560536

RESUMO

Background: There is a significant need for predictive and stable in vitro human liver representations for disease modeling and drug testing. Hepatic stellate cells (HSCs) and liver sinusoidal endothelial cells (LSECs) are important non-parenchymal cell components of the liver and are hence of relevance in a variety of disease models, including hepatic fibrosis. Pluripotent stem cell- (PSC-) derived HSCs (scHSCs) and LSECs (scLSECs) offer an attractive alternative to primary human material; yet, the suitability of scHSCs and scLSECs for extended in vitro modeling has not been characterized. Methods: In this study, we describe the phenotypic and functional development of scHSCs and scLSECs during 14 days of 2D in vitro culture. Cell-specific phenotypes were evaluated by cell morphology, immunofluorescence, and gene- and protein expression. Functionality was assessed in scHSCs by their capacity for intracellular storage of vitamin A and response to pro-fibrotic stimuli induced by TGF-ß. scLSECs were evaluated by nitric oxide- and factor VIII secretion as well as endocytic uptake of bioparticles and acetylated low-density lipoprotein. Notch pathway inhibition and co-culturing scHSCs and scLSECs were separately tested as options for enhancing long-term stability and maturation of the cells. Results and Conclusion: Both scHSCs and scLSECs exhibited a post-differentiation cell type-specific phenotype and functionality but deteriorated during extended culture with PSC line-dependent variability. Therefore, the choice of PSC line and experimental timeframe is crucial when designing in vitro platforms involving scHSCs and scLSECs. Notch inhibition modestly improved long-term monoculture in a cell line-dependent manner, while co-culturing scHSCs and scLSECs provides a strategy to enhance phenotypic and functional stability.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36542899

RESUMO

Organoids are laboratory-grown 3D organ models, mimicking human organs for e.g. drug development and personalized therapy. Islet organoids (typically 100-200 µm), which can be grown from the patient́s own cells, are emerging as prototypes for transplantation-based therapy of diabetes. Selective methods for quantifying insulin production from islet organoids are needed, but sensitivity and carry-over have been major bottlenecks in previous efforts. We have developed a reverse phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) method for studying the insulin secretion of islet organoids. In contrast to our previous attempts using nano-scale LC columns, conventional 2.1 mm inner diameter LC column (combined with triple quadrupole mass spectrometry) was well suited for sensitive and selective measurements of insulin secreted from islet organoids with low microliter-scale samples. Insulin is highly prone to carry-over, so standard tubings and injector parts were replaced with shielded fused silica connectors. As samples were expected to be very limited, an extended Box-Behnken experimental design for the MS settings was conducted to maximize performance. The finale method has excellent sensitivity, accuracy and precision (limit of detection: ≤0.2 pg/µL, relative error: ≤±10%, relative standard deviation: <10%), and was well suited for measuring 20 µL amounts of Krebs buffer containing insulin secreted from islet organoids.


Assuntos
Organoides , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Secreção de Insulina , Cromatografia Líquida/métodos , Organoides/metabolismo , Insulina/metabolismo , Células-Tronco/metabolismo
9.
Bioresour Technol ; 364: 128036, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36174892

RESUMO

Lithium battery slurry wastewater was successfully treatedby using basalt fiber (BF) bio-carriers in a biological contact oxidation reactor. This resulted in a significant reduction of COD (93.3 ± 0.5 %) and total nitrogen (77.4 ± 1.0 %) at 12 h of HRT and dissolved oxygen (DO) of 0-1 mg/L. The modified Stover-Kincannon model indicated that the total nitrogen removal rate was 4.462 kg/m3/d in R-BF while the substrate maximum specific reaction rate (qmax) in the Monod model was 0.323 mg-N/mgVSS/d. A stable internal environment was established within the bio-nest. Metataxonomic analysis revealed the presence of denitrification and decarbonization bacteria, combined heterotrophic nitrification-aerobic denitrification bacteria, nitrite-oxidizing bacteria, and ammonia-oxidizing bacteria. Functional analysis displayed changes related to (aerobic)chemoheterotrophy, nitrogen respiration, nitrate reduction, respiration/denitrification of nitrite, and nitrate in R-BF. The study proposes a novel approach to achieve denitrification for the treatment of lithium slurry wastewater at low C/N conditions.

10.
Diabetes ; 71(4): 862-869, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35043148

RESUMO

Studies of monogenic diabetes are particularly useful because we can gain insight into the molecular events of pancreatic ß-cell failure. Maturity-onset diabetes of the young 1 (MODY1) is a form of monogenic diabetes caused by a mutation in the HNF4A gene. Human-induced pluripotent stem cells (hiPSCs) provide an excellent tool for disease modeling by subsequently directing differentiation toward desired pancreatic islet cells, but cellular phenotypes in terminally differentiated cells are notoriously difficult to detect. Re-creating a spatial (three-dimensional [3D]) environment may facilitate phenotype detection. We studied MODY1 by using hiPSC-derived pancreatic ß-like patient and isogenic control cell lines in two different 3D contexts. Using size-adjusted cell aggregates and alginate capsules, we show that the 3D context is critical to facilitating the detection of mutation-specific phenotypes. In 3D cell aggregates, we identified irregular cell clusters and lower levels of structural proteins by proteome analysis, whereas in 3D alginate capsules, we identified altered levels of glycolytic proteins in the glucose sensing apparatus by proteome analysis. Our study provides novel knowledge on normal and abnormal function of HNF4A, paving the way for translational studies of new drug targets that can be used in precision diabetes medicine in MODY.


Assuntos
Diabetes Mellitus Tipo 2 , Células-Tronco Pluripotentes Induzidas , Alginatos/metabolismo , Cápsulas/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Mutação , Proteoma
11.
Environ Sci Pollut Res Int ; 28(22): 27614-27628, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33512680

RESUMO

Capacity development has been regarded as one of many measures to empower the abilities of nations to adapt to a changing climate. Promoting public engagement in water conservation, especially among young people since they will be leading decision making in the near future, is one effective strategy for adapting to the changing climate. This research presented a water footprint adaptation (WF) approach which attempted to link climate adaptation and capacity development with saving water strategy. The approach was tested in cooperation with two universities in Shaanxi province aiming to develop a starting point for WF evaluation and develop an improvement response. The results showed that the college students in our samples reduced their direct and indirect water footprints by 27.39% and 6.50%, respectively, in the post-intervention phase. The evaluation of the improvements proved that the WF approach to be efficient, the awareness of the college students on the matter could be increased. Additionally, the findings of the research indicated that the college students became change agent, expressing the desire to act as multipliers and to help the movement and spread of important knowledge about methods for alleviating water stress and about vulnerability to the changing climate. As expected, the awareness of water scarcity and perceptions of climate change had statistically significant effects on the water footprints, which was consistent with our hypothesis. Our approach helped participants develop capacity by revealing the linkage between their local level actions and the various aspects of adaptation to changing climate at the global level. This strategy will provide a comparative basis for water policy makers to adopt appropriate strategies to address matters related to water shortages and finally enhance sustainable adaptation to changing context.


Assuntos
Conservação dos Recursos Hídricos , Aclimatação , Adolescente , Fortalecimento Institucional , China , Mudança Climática , Humanos
12.
Appl Opt ; 60(34): 10625-10631, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200925

RESUMO

The realization of output of the controllable transverse mode in a laser resonator has always been the key problem in applications of lasers. At present, the theory of optical resonators for passive resonators is relatively mature, but the non-uniformity of gain media greatly affects the output of the laser transverse mode for astigmatic resonators in operation; especially for gas lasers, controllable high-order modes have not been studied. To realize the theory of an astigmatic passive resonator of a gas laser as a good approximation of an active resonator, this paper develops the theory of selecting the laser eigenmode through an astigmatic resonator, and verifies that the two-dimensional tilt of the cavity mirror can break the axial symmetry. Controllable output of the laser mode is realized in real time and conveniently for the first time, to the best of our knowledge. This scheme is not only common to all kinds of lasers, but also has important research significance for the high-order modes required for real-time and rapid regulation of gas lasers under operating conditions.

13.
Liver Int ; 40(2): 298-307, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31674705

RESUMO

BACKGROUND & AIMS: Trends in long-term mortality rates for viral hepatitis in East and Southeast Asia have been rarely reported. The aim of our study was to explore the long-term trends in viral hepatitis mortality rates in East and Southeast Asian countries between 1987 and 2015 and provide predictions of mortality to 2030. METHODS: We obtained viral hepatitis mortality data from the WHO Mortality Database for six East and Southeast Asian countries between 1987 and 2015. We produced choropleth maps of viral hepatitis mortality rates in 1987 and 2015 in East and Southeast Asia to illustrate geographic variations. We made predictions of mortality rates for each included country until the year 2030 using a series of joinpoint models. RESULTS: Viral hepatitis mortality rates declined in China (the average annual percent change (AAPC) = -5.1%, 95% CI: -7.5, -2.6), Singapore (AAPC = -5.4%, 95% CI: -7.5, -3.2), and the Philippines (AAPC = -3.4%, 95% CI: -4.9, -1.8). In contrast, Japan, the Republic of Korea, and Malaysia have experienced increasing trends in mortality rates, followed by decreasing trends. Our predictions indicate that all countries will experience slight to moderate downward trends until 2030. CONCLUSION: Favourable decreasing trends have been noted in East and Southeast Asian countries, which may not only inform the control and management of viral hepatitis in this region but also guide the prevention of viral hepatitis deaths in another region with a similar viral hepatitis epidemic.


Assuntos
Hepatite Viral Humana , Sudeste Asiático/epidemiologia , China , Hepatite Viral Humana/epidemiologia , Humanos , Japão , Mortalidade , República da Coreia , Singapura
14.
BMC Infect Dis ; 19(1): 617, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299910

RESUMO

BACKGROUND: The major infectious diseases of hepatitis B has constituted an acute public health challenge in China. An effective and affordable HBV control model is urgently needed. A national project of Community-based Collaborative Innovation HBV (CCI-HBV) demonstration areas has optimized the existing community healthcare resources and obtained initial results in HBV control. METHODS: Based on the existing community healthcare network, CCI-HBV project combined the community health management and health contract signing service for long-staying residents in hepatitis B screening. Moreover, HBV field research strategy was popularized in CCI-HBV areas. After screening, patients with seropositive results were enrolled in corresponding cohorts and received treatment at an early stage. And the uninfected people received medical supports including health education through new media, behavior intervention and HBV vaccinations. In this process, a cloud-based National Information Platform (NIP) was established to collect and store residents' epidemiological data. In addition, a special quality control team was set up for CCI project. RESULTS: After two rounds of screening, HBsAg positive rate dropped from 5.05% (with 5,173,003 people screened) to 4.57% (with 3,819,675 people screened), while the rate of new HBV infections was 0.28 per 100 person-years in the fixed cohorts of 2,584,322 people. The quality control team completed PPS sampling simultaneously and established the serum sample database with 2,800,000 serum samples for unified testing. CONCLUSIONS: CCI-HBV project has established a large-scale field research to conduct whole-population screening and intervention. We analyzed the HBsAg prevalence and new infection rate of HBV in the fixed population for the epidemic trend and intervention effect. The purpose of CCI-HBV project is to establish and evaluate a practical model of grid management and field strategy, to realize the new goal to control hepatitis B in China. To provide policymakers with a feasible model, our results are directly applicable. TRIAL REGISTRATION: The project was funded by the Major Projects of Science Research for the 11th and 12th five-year plans of China, entitled "The prevention and control of AIDS, viral hepatitis and other major infectious diseases", Grant Nos. 2009ZX10004901, 2011ZX10004901, 2013ZX10004904, 2014ZX10004007 and 2014ZX10004008.


Assuntos
Bases de Dados Factuais , Hepatite B/epidemiologia , Adolescente , China/epidemiologia , Computação em Nuvem , Serviços de Saúde Comunitária , Feminino , Política de Saúde , Hepatite B/diagnóstico , Hepatite B/prevenção & controle , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
15.
Appl Plant Sci ; 7(2): e01222, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30828508

RESUMO

PREMISE OF THE STUDY: We developed microsatellite primers for Rhododendron shanii (Ericaceae), a narrowly distributed species found in the Dabie Mountains, China, to study the genetic diversity, population structure, and evolutionary history of the species. METHODS AND RESULTS: Two terminal sequencing modes of the Illumina HiSeq platform were used to mine simple sequence repeat markers from large-scale transcriptional groups. In this study, 24 microsatellite loci were screened. The number of alleles ranged from one to 20, and the levels of observed and expected heterozygosity ranged from 0.000 to 1.000 and 0.000 to 0.918, respectively. Most of these primers were successfully amplified in eight congeneric species (R. annae, R. chihsinianum, R. decorum, R. denudatum, R. fortunei, R. neriiflorum, R. rex, and R. simiarum). CONCLUSIONS: These newly developed microsatellite loci will be useful for studying the genetic diversity and population structure of R. shanii and congeneric species.

16.
Hepatology ; 69(4): 1442-1452, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30561833

RESUMO

The launch of new direct-acting antivirals (DAAs) is expected to substantially reduce the burden of hepatitis C virus (HCV) in China. However, the effect of these changes has not yet been modeled in China. Therefore, we aim to predict the burden of HCV-related diseases in China by simulating different scenarios that incorporate recent therapeutic advances of HCV and China's current screening strategy. We developed an individual-based microsimulation Markov model that simulated disease progression of HCV-infected patients in China from 2004 to 2050. We simulated four scenarios with different assumptions about treatment, including a natural history scenario, a pre-DAAs scenario, a DAA treatment for all patients with a METAVIR fibrosis score ≥F3 (DAAs [≥F3]) scenario, and a DAAs (≥F0) scenario. The introduction of DAAs is predicted to have great impacts on the burden of HCV in China, particularly under the DAAs (≥F0) scenario in which we rapidly expand DAAs to all HCV-infected patients (≥F0) in 2021. Under this scenario, prevalence of chronic HCV is expected to peak at 10.75 million (95% confidence interval [CI], 8.30-12.85) around 2020 and then decrease to 7.92 million (95% CI, 5.41-10.08) in 2050. Conclusion: If the future increasing burden of HCV-related diseases is to be averted, China needs to start launching the new DAA treatment and rapidly increase the number of patients treated. However, to maximize the benefits of new DAAs, expanded screening is necessary to identify more cases that require treatment in the short term. Without these changes, the HCV burden in China will remain high in the future.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/epidemiologia , Modelos Teóricos , China/epidemiologia , Feminino , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Cadeias de Markov , Prevalência
17.
BMC Bioinformatics ; 19(Suppl 20): 502, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577745

RESUMO

BACKGROUND: Biomedical semantic indexing is important for information retrieval and many other research fields in bioinformatics. It annotates biomedical citations with Medical Subject Headings. In face of unbalanced category distribution in the training data, sampling methods are difficult to apply for semantic indexing task. RESULTS: In this paper, we present a novel deep serial multi-task learning model. The primary task treats the biomedical semantic indexing as a multi-label text classification issue that considers the relations of the labels. The auxiliary task is a regression task that predicts the MeSH number of the citation and provides hints for the network to make it converge faster. The experimental results on the BioASQ-Task5A open dataset show that our model outperforms the state-of-the-art solution "MTI", proposed by the US National Library of Medicine. Further, it not only achieves the highest precision among all the solutions in BioASQ-Task5A but also has faster convergence speed compared with some naive deep learning methods. CONCLUSIONS: Rather than parallel in an ordinary multi-task structure, the tasks in our model are serial and tightly coupled. It can achieve satisfied performance without any handcrafted feature.


Assuntos
Indexação e Redação de Resumos , Aprendizado Profundo , Redes Neurais de Computação , Semântica , Algoritmos , Humanos
18.
PLoS One ; 13(11): e0207063, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30452446

RESUMO

Trajectory data uploaded by mobile devices is growing quickly. It represents the movement of an individual or a device based on the longitude and latitude coordinates collected by GPS. The location based service has a broad application prospect in the real world. As the traditional location prediction models which are based on the discrete state sequence cannot predict the locations in real time, we propose a Continuous Time Series Markov Model (CTS-MM) to solve this problem. The method takes the Gaussian Mixed Model (GMM) to simulate the posterior probability of a location in the continuous time series. The probability calculation method and state transition model of the Hidden Markov Model (HMM) are improved to get the precise location prediction. The experimental results on GeoLife data show that CTS-MM performs better for location prediction in exact minute than traditional location prediction models.


Assuntos
Sistemas de Informação Geográfica/estatística & dados numéricos , Cadeias de Markov , Modelos Estatísticos , Algoritmos , Telefone Celular , Análise por Conglomerados , Distribuição Normal , Fatores de Tempo
19.
Gastroenterology ; 154(6): 1719-1728.e5, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29549041

RESUMO

BACKGROUND & AIMS: We examined temporal trends in liver cancer incidence rates overall and by histological type from 1983 through 2007. We predict trends in liver cancer incidence rates through 2030 for selected Eastern and Southeastern Asian countries. METHODS: Data on yearly liver cancer incident cases by age group and sex were drawn from 6 major selected Eastern and Southeastern Asian countries or regions with cancer registries available in the CI5plus database, including China, Japan, Hong Kong Special Administrative Region (SAR), the Philippines, Singapore, and Thailand. We also analyzed data for the United States and Australia for comparative purposes. Age-standardized incidence rates were calculated and plotted from 1983 through 2007. Numbers of new cases and incidence rates were predicted through 2030 by fitting and extrapolating age-period-cohort models. RESULTS: The incidence rates of liver cancer have been decreasing, and decreases will continue in all selected Eastern and Southeastern Asian countries, except for Thailand, whose liver cancer incidence rate will increase due to the increasing incidence rate of intrahepatic cholangiocarcinomas. Even though the incidence rates of liver cancer are predicted to decrease in most Eastern and Southeastern Asian countries, the burden, in terms of new cases, will continue to increase because of population growth and aging. CONCLUSIONS: Based on an analysis of data from cancer registries from Asian countries, incidence rates of liver cancer are expected to decrease through 2030 in most Eastern and Southeastern Asian countries. However, in Thailand, the incidence rate of intrahepatic cholangiocarcinomas is predicted to increase, so health education programs are necessary.


Assuntos
Neoplasias Hepáticas/epidemiologia , Austrália/epidemiologia , Neoplasias dos Ductos Biliares/epidemiologia , China/epidemiologia , Colangiocarcinoma/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Previsões , Hong Kong/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Filipinas/epidemiologia , Sistema de Registros , Singapura/epidemiologia , Tailândia/epidemiologia , Estados Unidos/epidemiologia
20.
Clin Infect Dis ; 65(10): 1721-1728, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29020363

RESUMO

BACKGROUND: Pneumonia is now the second leading cause of death for children aged <5 years worldwide. However, analyses of the long-term evolution of under-5 mortality from pneumonia are still scarce in the literature. We aimed to explore long-term trends of under-5 mortality from pneumonia in 56 countries from 1960 to 2012. METHODS: Data on under-5 mortality from pneumonia were extracted from the World Health Organization mortality database. Long-term trends were assessed for 56 countries and for 4 national income transition groups. We also used joinpoint regression analysis to detect distinct period segments of long-term trends and estimate the annual percent of changes of each period segment. RESULTS: The average mortality rate from pneumonia for children aged 0-4 years in 56 countries declined from 163.0 per 100000 children (95% confidence interval [CI], 119.4 to 212.8) in 1960 to 9.9 per 100000 children (95% CI, 6.4 to 13.4) in 2012, with an average annual percent of change of -5.6% (95% CI, -7.2% to -3.9%). The temporal trends of childhood mortality were different between national income transition groups. CONCLUSIONS: Our findings suggest a striking overall downward trend in under-5 mortality from pneumonia between 1960 and 2012. However, the rate and absolute terms of decline differ by national income transition group. These variable patterns between national income transition groups may inform further intervention setting and priority setting.


Assuntos
Pneumonia/mortalidade , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Análise de Regressão , Estudos Retrospectivos , Organização Mundial da Saúde
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