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1.
Curr Pharm Des ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32067604

RESUMO

BACKGROUND: Metformin has been associated with improved survival outcomes in various malignancies. However, observational studies in head and neck cancer are inconsistent. OBJECTIVE: The study aimed to summarize and quantify the relationship between metformin use and the survival of head and neck cancer. METHODS: We systematically conducted a meta-analysis based on cohort studies published up to Jan 18, 2020, identified from PubMed, Embase, Web of Science, Cochrane Library, Google Scholar, and Scopus databases. Summary hazard ratios (HR) and 95% confidence intervals (CI) were calculated using a random-effects model. RESULTS: Seven retrospective cohort studies including 3,285 head and neck cancer patients were included. The association between use of metformin and cancer survival was not statistically significant: summarized HR of 0.89 (95% CI 0.66-1.18, P=0.413, I2=64.0%) for overall survival, summarized HR of 0.65 (95% CI 0.31-1.35, P=0.246, I2=60.3%) for disease-free survival, and summarized HR of 0.69 (95% CI 0.40-1.20, P=0.191, I2=73.1%) for disease-specific survival. CONCLUSION: In this meta-analysis of 7 retrospective cohort studies, there was not a statistically significant association between use of metformin and better survival for head and neck cancer. However, the analysis may have been underpowered. More studies of prospective designs with larger sample sizes are needed to investigate the effect of metformin on the survival for head and neck cancer.

2.
Nucleic Acids Res ; 48(5): 2733-2748, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32009146

RESUMO

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.

3.
Sci China Life Sci ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32086672

RESUMO

RNA splicing dysregulation is widespread in cancer. Accumulating evidence demonstrates that splicing defects resulting from splicing dysregulation play critical roles in cancer pathogenesis and can serve as new biomarkers and therapeutic targets for cancer intervention. These findings have greatly deepened the mechanistic understandings of the regulation of alternative splicing in cancer cells, leading to rapidly growing interests in targeting cancer-related splicing defects as new therapies. Here we summarize the current research progress on splicing dysregulation in cancer and highlight the strategies available or under development for targeting RNA splicing defects in cancer.

4.
Eur J Med Chem ; 192: 112163, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32109623

RESUMO

Herein, 11 general types of natural cannabinoids from Cannabis sativa as well as 50 (-)-CBD analogues with therapeutic potential were described. The underlying molecular mechanisms of CBD as a therapeutic candidate for epilepsy and neurodegenerative diseases were comprehensively clarified. CBD indirectly acts as an endogenous cannabinoid receptor agonist to exert its neuroprotective effects. CBD also promotes neuroprotection through different signal transduction pathways mediated indirectly by cannabinoid receptors. Furthermore, CBD prevents the glycogen synthase kinase 3ß (GSK-3ß) hyperphosphorylation caused by Aß and may be developed as a new therapeutic candidate for Alzheimer's disease.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31944948

RESUMO

The Radon transform is widely used in physical and life sciences, and one of its major applications is in medical X-ray computed tomography (CT), which is significantly important in disease screening and diagnosis. In this paper, we propose a novel reconstruction framework for Radon inversion with deep learning (DL) techniques. For simplicity, the proposed framework is denoted as iRadonMAP, i.e., inverse Radon transform approximation. Specifically, we construct an interpretable neural network that contains three dedicated components. The first component is a fully connected filtering (FCF) layer along the rotation angle direction in the sinogram domain, and the second one is a sinusoidal back-projection (SBP) layer, which back-projects the filtered sinogram data into the spatial domain. Next, a common network structure is added to further improve the overall performance. iRadonMAP is first pretrained on a large number of generic images from the ImageNet database and then fine-tuned with clinical patient data. The experimental results demonstrate the feasibility of the proposed iRadonMAP framework for Radon inversion.

6.
Eur J Cancer Prev ; 29(1): 42-52, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30950925

RESUMO

Preclinical studies have suggested the antitumorigenic properties of metformin on prostate cancer; results from epidemiological studies remain contradictory. We aim to investigate the evidence of metformin and the risk of prostate cancer. PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible studies. Meta-analyses were carried out using the most fully adjusted hazard ratios and the corresponding 95% confidence intervals. Eighteen cohort studies and six case-control studies representing 2 009 504 male patients with type 2 diabetes mellitus were identified. The pooled HR of prostate cancer for metformin therapy was 0.97 (0.84-1.12) in case-control studies and 0.94 (0.79-1.12) in cohort studies, respectively. In cohort studies, we found that there was a modest association in studies with samples from Europe, but not in studies with samples from North America, Asia, and Oceania. In addition, metformin showed a slightly protective effect compared with sulfonylurea, but not insulin and other comparators. Meta-regression analyses found that obesity and prostate-specific antigen adjustment in statistical models may be the sources of heterogeneity. However, there were no significant differences in subgroups stratified by time-related biases, analytical approaches, types of risk estimates, study quality, publication year, and whether adjusted for smoking, alcohol abuse, hemoglobin A1c, diabetes duration, and other confounding factors. Our study showed that metformin therapy was not associated with the risk of prostate cancer in patients with type 2 diabetes mellitus. However, exploratory analyses suggest that metformin use may be protective in a certain subgroup of patients.

7.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(10): 1213-1220, 2019 Oct 30.
Artigo em Chinês | MEDLINE | ID: mdl-31801709

RESUMO

OBJECTIVE: We propose a sparse-view helical CT iterative reconstruction algorithm based on projection of convex set tensor total generalized variation minimization (TTGV-POCS) to reduce the X-ray dose of helical CT scanning. METHODS: The three-dimensional volume data of helical CT reconstruction was viewed as the third-order tensor. The tensor generalized total variation (TTGV) was used to describe the structural sparsity of the three-dimensional image. The POCS iterative reconstruction framework was adopted to achieve a robust result of sparse-view helical CT reconstruction. The TTGV-POCS algorithm fully used the structural sparsity of first-order and second-order derivation and the correlation between the slices of helical CT image data to effectively suppress artifacts and noise in the image of sparse-view reconstruction and better preserve image edge information. RESULTS: The experimental results of XCAT phantom and patient scan data showed that the TTGVPOCS algorithm had better performance in reducing noise, removing artifacts and maintaining edges than the existing reconstruction algorithms. Comparison of the sparse-view reconstruction results of XCAT phantom data with 144 exposure views showed that the TTGV-POCS algorithm proposed herein increased the PSNR quantitative index by 9.17%-15.24% compared with the experimental comparison algorithm; the FSIM quantitative index was increased by 1.27%-9.30%. CONCLUSIONS: The TTGV-POCS algorithm can effectively improve the image quality of helical CT sparse-view reconstruction and reduce the radiation dose of helical CT examination to improve the clinical imaging diagnosis.


Assuntos
Processamento de Imagem Assistida por Computador , Doses de Radiação , Tomografia Computadorizada Espiral , Algoritmos , Humanos , Imagens de Fantasmas
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(11): 1320-1328, 2019 Nov 30.
Artigo em Chinês | MEDLINE | ID: mdl-31852651

RESUMO

OBJECTIVE: Sparse-view CT has the advantages of accelerated data collection and reduced radiation dose, but data missing arising from the data collection process causes serious streaking artifact and noise in the images reconstructed using the traditional filtering back projection algorithm (FBP). To solve this problem, we propose a multi-scale wavelet residual network (MWResNet) to restore sparse-view CT images. METHODS: The MWResNet was based on the combination of deep learning and traditional model in MWCNN, and the wavelet network was combined with the residual block to enhance the network's ability to embed image features and speed up network training. The network proposed herein was trained using the real spiral geometry CT image data, namely the Low-dose CT Grand Challenge dataset. The results of the proposed networks were visually and quantitatively compared to that by other existing networks, including the image restoration iterative residual convolution network (IRLNet), residual coding-decoding convolutional neural network (REDCNN) and the FBP convolutional neural network (FBPConvNet). RESULTS: The results demonstrated that the proposed method was superior to other competing methods in terms of visual inspection and quantitative comparison. CONCLUSIONS: The MWResNet network is an effective method for suppressing noise and artifacts and maintaining edges details in the sparse-view CT images.


Assuntos
Tomografia Computadorizada por Raios X , Algoritmos , Artefatos , Processamento de Imagem Assistida por Computador
9.
Reprod Biomed Online ; 39(4): 674-684, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31540847

RESUMO

RESEARCH QUESTION: Is pre-pregnancy maternal underweight associated with perinatal outcomes of singletons who were conceived through assisted reproductive technology (ART)? DESIGN: A 10-year (2006-2015) Chinese sample of 6538 women and their singleton infants who were conceived through ART was used to examine the association between pre-pregnancy maternal underweight and perinatal outcomes. Propensity scores for underweight were calculated for each participant using multivariable logistic regression, which was used to match 740 (91.36% of 810) underweight women with 740 normal weight women; the effects of underweight on birth weight and gestational age were then assessed by generalized estimating equation model. RESULTS: After propensity score matching, the birth weight was lower (difference -136.83 g, 95% CI -184.11 to -89.55 g) in the underweight group than in the normal weight group. The risks of low birth weight (LBW) and small for gestational age (SGA) were increased in the underweight group compared with those in the normal weight group (LBW: RR 1.64, 95% CI 1.01 to 2.67; SGA: RR 1.46, 95% CI 1.06 to 2.02). The risks of fetal macrosomia and being large for gestational age (LGA) were decreased in the underweight group compared with those in the normal weight group (macrosomia: RR 0.39, 95% CI 0.26 to 0.61; LGA: RR 0.36, 95% CI 0.24 to 0.53). The associations between underweight, gestational age and preterm birth were not statistically significant. CONCLUSIONS: Among women undergoing ART, pre-pregnancy maternal underweight was associated with lower birth weight, increased LBW and SGA risks, and decreased fetal macrosomia and LGA risks in singleton infants.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31425024

RESUMO

For decades, commercial X-ray computed tomography (CT) scanners have been using the filtered backprojection (FBP) algorithm for image reconstruction. However, the desire for lower radiation doses has pushed the FBP algorithm to its limit. Previous studies have made significant efforts to improve the results of FBP through preprocessing the sinogram, modifying the ramp filter, or postprocessing the reconstructed images. In this paper, we focus on analyzing and processing the stacked view-by-view backprojections (named VVBP-Tensor) in the FBP algorithm. A key challenge for our analysis lies in the radial structures in each backprojection slice. To overcome this difficulty, a sorting operation was introduced to the VVBP-Tensor in its z direction (the direction of the projection views). The results show that, after sorting, the tensor contains structures that are similar to those of the object, and structures in different slices of the tensor are correlated. We then analyzed the properties of the VVBP-Tensor, including structural self-similarity, tensor sparsity, and noise statistics. Considering these properties, we have developed an algorithm using the tensor singular value decomposition (named VVBP-tSVD) to denoise the VVBP-Tensor for low-mAs CT imaging. Experiments were conducted using a physical phantom and clinical patient data with different mAs levels. The results demonstrate that the VVBP-tSVD is superior to all competing methods under different reconstruction schemes, including sinogram preprocessing, image postprocessing, and iterative reconstruction. We conclude that the VVBP-Tensor is a suitable processing target for improving the quality of FBP reconstruction, and the proposed VVBP-tSVD is an effective algorithm for noise reduction in low-mAs CT imaging. This preliminary work might provide a heuristic perspective for reviewing and rethinking the FBP algorithm.

11.
Curr Pharm Des ; 25(23): 2595-2601, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333095

RESUMO

BACKGROUND: A number of observational studies examined the association between metformin therapy and ovarian cancer survival outcomes, but the results are inconsistent. OBJECTIVE: The study aimed to investigate the effect of metformin on survival for ovarian cancer patients. METHOD: PubMed, Embase and Web of Science databases were searched for relevant studies from the inception to June 11, 2019. The strength of the relationship was assessed using summary of hazard ratios (HRs) with corresponding 95% confidence intervals (CI). Statistical analyses were carried out using the random-effects model. RESULTS: Totally, 6 retrospective cohort studies involving 2,638 ovarian cancer patients were included. Metformin was not associated with improved overall survival (HR=0.78, 95% CI 0.54-1.12, P=0.175, I2= 61.6%) and disease- free survival (HR=0.49, 95% CI 0.20-1.17, P=0.106, I2=82.1%) in ovarian cancer patients compared to nonmetformin users. CONCLUSION: The current study provides preliminary evidence that metformin may not be associated with a survival benefit for ovarian cancer patients. More studies with rigorous designs are needed.

12.
Cancer Epidemiol ; 61: 95-103, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176961

RESUMO

BACKGROUND: Bladder cancer is closely related to occupational carcinogens, and China is undergoing a rapid industrialization. However, trend of bladder cancer incidence and mortality remains unknown in China. METHODS: Incidence and mortality rates of bladder cancer (1990-2017) were collected for each 5-year age group stratified by gender (males/females) from the Global Burden of Disease (GBD) 2017 study. The average annual percentage change (AAPC) of rates were analyzed by joinpoint regression analysis; age, period and cohort effects on incidence and mortality were simultaneously estimated by age-period-cohort model. RESULTS: Through 1990-2017, age-standardized incidence rates significantly rose in men (AAPC = 0.72%, 95% CI: 0.5%, 0.9%) while decreased in women (-1.25%: -1.6%, -0.9%); age-standardized mortality rates decreased in both men (-1.09%: -1.2%, -0.9%) and women (-2.48%: -2.8%, -2.2%). The joinpoint regression analysis showed the mortality almost decreased in all age groups; while the incidence increased in men for older age groups (from 45 to 49 to 80-84). Moreover, age effect showed the incidence and mortality increased with age; the incidence and mortality increased with time period, while in women period effect stop decreasing and began to increase since 2007; cohort effect showed them decreased with birth cohorts. CONCLUSIONS: The incidence of bladder cancer is increasing in men but mortality decreases in both sexes. Both the incidence and mortality in men substantially increase with age and period, while the rates in women increased with period since 2007. The period effect may indicate the increased risks to bladder cancer in Chinese men. Etiological studies are needed to identify the factors driving these trends of bladder cancer.

13.
Nat Commun ; 10(1): 2376, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147536

RESUMO

Proxy-based reconstructions and modeling of Holocene spatiotemporal precipitation patterns for China and Mongolia have hitherto yielded contradictory results indicating that the basic mechanisms behind the East Asian Summer Monsoon and its interaction with the westerly jet stream remain poorly understood. We present quantitative reconstructions of Holocene precipitation derived from 101 fossil pollen records and analyse them with the help of a minimal empirical model. We show that the westerly jet-stream axis shifted gradually southward and became less tilted since the middle Holocene. This was tracked by the summer monsoon rain band resulting in an early-Holocene precipitation maximum over most of western China, a mid-Holocene maximum in north-central and northeastern China, and a late-Holocene maximum in southeastern China. Our results suggest that a correct simulation of the orientation and position of the westerly jet stream is crucial to the reliable prediction of precipitation patterns in China and Mongolia.

14.
Clinics (Sao Paulo) ; 74: e736, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038562

RESUMO

OBJECTIVE: To assess the efficacy and safety of sitagliptin compared with voglibose added to combined metformin and insulin in patients with newly diagnosed type 2 diabetes (T2DM). METHODS: In this 12-week prospective, randomized, parallel trial, 70 newly diagnosed T2DM patients with glycosylated hemoglobin (HbA1c) ≥9% and/or fasting plasma glucose (FPG) ≥11.1 mmol/L were randomized (1:1) to receive sitagliptin 100 mg per day + metformin + insulin glargine or voglibose 0.2 mg three times daily + metformin + insulin glargine. Change in HbA1c at week 12 was the primary endpoint. RESULTS: The mean baseline HbA1c was 11.0% in the patients. The changes in HbA1c from baseline were -6.00% in the sitagliptin group and -3.58% in the voglibose group, and the between-group difference was -2.42% (95% CI -1.91 to -2.93, p=0.02). The differences in FPG and homeostatic model assessment of ß-cell function (HOMA-ß) and the change in body weight between groups from baseline were -2.95 mmol/L (p=0.04), 43.91 (p=0.01) and -2.23 kg (p=0.01), respectively. One patient (2.9%) in the sitagliptin group and three patients (8.6%) in the voglibose group exhibited hypoglycemia. CONCLUSIONS: Sitagliptin added to combined metformin and insulin therapy showed greater efficacy and good safety regarding hypoglycemia in patients with newly diagnosed T2DM compared with voglibose.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Inositol/análogos & derivados , Metformina/uso terapêutico , Fosfato de Sitagliptina/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Inositol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
15.
Mol Genet Genomics ; 294(4): 1059-1071, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31020414

RESUMO

Ventricular tachycardia (VT) causes sudden cardiac death, however, the majority of risk genes for VT remain unknown. SCN4B encodes a ß-subunit, Navß4, for the voltage-gated cardiac sodium channel complex involved in generation and conduction of the cardiac action potential. We hypothesized that genomic variants in SCN4B increase the risk of VT. We used high-resolution melt analysis followed by Sanger sequencing to screen 199 VT patients to identify nonsynonymous variants in SCN4B. Two nonsynonymous heterozygous variants in SCN4B were identified in VT patients, including p.Gly8Ser in four VT patients and p.Ala145Ser in one VT patient. Case-control association studies were used to assess the association between variant p.Gly8Ser and VT in two independent populations for VT (299 VT cases vs. 981 controls in population 1 and 270 VT patients vs. 639 controls in population 2). Significant association was identified between p.Gly8Ser and VT in population 1 (P = 1.21 × 10-4, odds ratio or OR = 11.04), and the finding was confirmed in population 2 (P = 0.03, OR = 3.62). The association remained highly significant in the combined population (P = 3.09 × 10-5, OR = 6.17). Significant association was also identified between p.Gly8Ser and idiopathic VT (P = 1.89 × 10-5, OR = 7.27). Functional analysis with Western blotting showed that both p.Gly8Ser and p.Ala145Ser variants significantly reduced the expression level of Navß4. Based on 2015 ACMG Standards and Guidelines, p.Gly8Ser and p.Ala145Ser can be classified as the pathogenic and likely pathogenic variant, respectively. Our data suggest that SCN4B is a susceptibility gene for common VT and idiopathic VT and link rare SCN4B variants with large effects (OR = 6.17-7.27) to common VT.


Assuntos
Substituição de Aminoácidos , Análise de Sequência de DNA/métodos , Taquicardia Ventricular/genética , Subunidade beta-4 do Canal de Sódio Disparado por Voltagem/genética , Adulto , Idoso , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/metabolismo , Subunidade beta-4 do Canal de Sódio Disparado por Voltagem/metabolismo
16.
Mikrochim Acta ; 186(5): 277, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30969364

RESUMO

A ratiometric fluorescent nanoprobe is described for the detection of H2O2. It is based on the use of a mixture of green-emitting CdTe quantum dots (GQDs) and red-emitting CdTe QDs (RQDs). The two kinds of QDs have different size and different fluorescence response towards H2O2. The ratio of the emission intensities at 606 and 510 nm (under 365 nm photoexcitation) can be used as the analytical information. Even without any chemical modification of the surface of the QDs, the probe display high sensitivity and selectivity for H2O2. The fluorescence of small QDs is more effectively quenched by H2O2. Stern-Volmer analysis showed both static and dynamic quenching to occur. The probe works well in the 10~125 µM H2O2 concentration range and has a 0.3 µM detection limit (3σ/slope). Graphical abstract Schematic presentation of the ratiometric fluorescent nanoprobe composed of green-emitting and red-emitting CdTe QDs. λ, I, and k are the emission wavelength, emission intensity, and quenching/enhancement coefficient, respectively. The subscript 0 and 1 present the green-emitting and red-emitting CdTe QDs, respectively.

17.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(2): 192-200, 2019 02 28.
Artigo em Chinês | MEDLINE | ID: mdl-30890508

RESUMO

OBJECTIVE: To develop a digital breast tomosynthesis (DBT) imaging system with optimizes imaging chain. METHODS: Based on 3D tomography and DBT imaging scanning, we analyzed the methods for projection data correction, geometric correction, projection enhancement, filter modulation, and image reconstruction, and established a hardware testing platform. In the experiment, the standard ACR phantom and high-resolution phantom were used to evaluate the system stability and noise level. The patient projection data of commercial equipment was used to test the effect of the imaging algorithm. RESULTS: In the high-resolution phantom study, the line pairs were clear without confusing artifacts in the images reconstructed with the geometric correction parameters. In ACR phantom study, the calcified foci, cysts, and fibrous structures were more clearly defined in the reconstructed images after filtering and modulation. The patient data study showed a high contrast between tissues, and the lesions were more clearly displayed in the reconstructed image. CONCLUSIONS: This DBT imaging system can be used for mammary tomography with an image quality comparable to that of commercial DBT systems to facilitate imaging diagnosis of breast diseases.


Assuntos
Mama/diagnóstico por imagem , Mamografia/métodos , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/métodos , Algoritmos , Artefatos , Feminino , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-30626127

RESUMO

Background: The prevalence of diabetes mellitus is rapidly increasing in China, but the secular trends in incidence and mortality remain unknown. This study aims to examine time trends from 1990 to 2017 and the net age, period, and cohort effects on diabetes incidence and mortality. Methods: Incidence and mortality rates of diabetes (1990⁻2017) were collected for each 5-year age group (from 5⁻9 to 80⁻84 age group) stratified by gender from the Global Burden of Disease 2017 Study. The average annual percentage changes in incidence and mortality were analyzed by joinpoint regression analysis; the net age, period, and cohort effects on the incidence and mortality were estimated by age-period-cohort analysis. Results: The joinpoint regression analysis showed that age-standardized incidence significantly rose by 0.92% (95% CI: 0.6%, 1.3%) in men and 0.69% in women (95% CI: 0.3%, 1.0%) from 1990 to 2017; age-standardized mortality rates rose by 0.78% (95% CI: 0.6%, 1.0%) in men and decreased by 0.12% (95% CI: -0.4%, 0.1%) in women. For age-specific rates, incidence increased in most age groups, with exception of 30⁻34, 60⁻64, 65⁻69 and 70⁻74 age groups in men and 25⁻29, 30⁻34, 35⁻39 and 70⁻74 age groups in women; mortality in men decreased in the younger age groups (from 20⁻24 to 45⁻49 age group) while increased in the older age groups (from 50⁻54 to 80⁻84 age group), and mortality in women decreased for all age groups with exception of the age group 75⁻79 and 80⁻84. The age effect on incidence showed no obvious changes with advancing age while mortality significantly increased with advancing age; period effect showed that both incidence and mortality increased with advancing time period while the period trend on incidence began to decrease since 2007; cohort effect on incidence and mortality decreased from earlier birth cohorts to more recent birth cohorts while incidence showed no material changes from 1982⁻1986 to 2012⁻2016 birth cohort. Conclusions: Mortality decreased in younger age groups but increased in older age groups. Incidence increased in most age groups. The net age or period effect showed an unfavorable trend while the net cohort effect presented a favorable trend. Aging likely drives a continued increase in the mortality of diabetes. Timely population-level interventions aiming for obesity prevention, healthy diet and regular physical activity should be conducted, especially for men and earlier birth cohorts at high risk of diabetes.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Mellitus/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Efeito de Coortes , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Adulto Jovem
19.
IEEE Trans Med Imaging ; 38(2): 360-370, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30106716

RESUMO

Cerebrovascular diseases, i.e., acute stroke, are a common cause of serious long-term disability. Cerebral perfusion computed tomography (CPCT) can provide rapid, high-resolution, quantitative hemodynamic maps to assess and stratify perfusion in patients with acute stroke symptoms. However, CPCT imaging typically involves a substantial radiation dose due to its repeated scanning protocol. Therefore, in this paper, we present a low-dose CPCT image reconstruction method to yield high-quality CPCT images and high-precision hemodynamic maps by utilizing the great similarity information among the repeated scanned CPCT images. Specifically, a newly developed low-rank tensor decomposition with spatial-temporal total variation (LRTD-STTV) regularization is incorporated into the reconstruction model. In the LRTD-STTV regularization, the tensor Tucker decomposition is used to describe global spatial-temporal correlations hidden in the sequential CPCT images, and it is superior to the matricization model (i.e., low-rank model) that fails to fully investigate the prior knowledge of the intrinsic structures of the CPCT images after vectorizing the CPCT images. Moreover, the spatial-temporal TV regularization is used to characterize the local piecewise smooth structure in the spatial domain and the pixels' similarity with the adjacent frames in the temporal domain, because the intensity at each pixel in CPCT images is similar to its neighbors. Therefore, the presented LRTD-STTV model can efficiently deliver faithful underlying information of the CPCT images and preserve the spatial structures. An efficient alternating direction method of multipliers algorithm is also developed to solve the presented LRTD-STTV model. Extensive experimental results on numerical phantom and patient data are clearly demonstrated that the presented model can significantly improve the quality of CPCT images and provide accurate diagnostic features in hemodynamic maps for low-dose cases compared with the existing popular algorithms.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Circulação Cerebrovascular/fisiologia , Humanos , Imagens de Fantasmas
20.
IEEE Trans Med Imaging ; 38(2): 371-382, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30106717

RESUMO

Reducing the exposure to X-ray radiation while maintaining a clinically acceptable image quality is desirable in various CT applications. To realize low-dose CT (LdCT) imaging, model-based iterative reconstruction (MBIR) algorithms are widely adopted, but they require proper prior knowledge assumptions in the sinogram and/or image domains and involve tedious manual optimization of multiple parameters. In this paper, we propose a deep learning (DL)-based strategy for MBIR to simultaneously address prior knowledge design and MBIR parameter selection in one optimization framework. Specifically, a parameterized plug-and-play alternating direction method of multipliers (3pADMM) is proposed for the general penalized weighted least-squares model, and then, by adopting the basic idea of DL, the parameterized plug-and-play (3p) prior and the related parameters are optimized simultaneously in a single framework using a large number of training data. The main contribution of this paper is that the 3p prior and the related parameters in the proposed 3pADMM framework can be supervised and optimized simultaneously to achieve robust LdCT reconstruction performance. Experimental results obtained on clinical patient datasets demonstrate that the proposed method can achieve promising gains over existing algorithms for LdCT image reconstruction in terms of noise-induced artifact suppression and edge detail preservation.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Bases de Dados Factuais , Aprendizado Profundo , Humanos , Radiografia Torácica
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