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1.
Eur Radiol ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965257

RESUMO

OBJECTIVES: To propose a transfer learning (TL) radiomics model that efficiently combines the information from gray scale and elastogram ultrasound images for accurate liver fibrosis grading. METHODS: Totally 466 patients undergoing partial hepatectomy were enrolled, including 401 with chronic hepatitis B and 65 without fibrosis pathologically. All patients received elastography and got liver stiffness measurement (LSM) 2-3 days before surgery. We proposed a deep convolutional neural network by TL to analyze images of gray scale modality (GM) and elastogram modality (EM). The TL process was used for liver fibrosis classification by Inception-V3 network which pretrained on ImageNet. The diagnostic performance of TL and non-TL was compared. The value of single modalities, including GM and EM alone, and multimodalities, including GM + LSM and GM + EM, was evaluated and compared with that of LSM and serological indexes. Receiver operating characteristic curve analysis was performed to calculate the optimal area under the curve (AUC) for classifying fibrosis of S4, ≥ S3, and ≥ S2. RESULTS: TL in GM and EM demonstrated higher diagnostic accuracy than non-TL, with significantly higher AUCs (all p < .01). Single-modal GM and EM both performed better than LSM and serum indexes (all p < .001). Multimodal GM + EM was the most accurate prediction model (AUCs are 0.950, 0.932, and 0.930 for classifying S4, ≥ S3, and ≥ S2, respectively) compared with GM + LSM, GM and EM alone, LSM, and biomarkers (all p < .05). CONCLUSIONS: Liver fibrosis can be staged by a transfer learning modal based on the combination of gray scale and elastogram ultrasound images, with excellent performance. KEY POINTS: • Transfer learning consists in applying to a specific deep learning algorithm that pretrained on another relevant problem, expected to reduce the risk of overfitting due to insufficient medical images. • Liver fibrosis can be staged by transfer learning radiomics with excellent performance. • The most accurate prediction model of transfer learning by Inception-V3 network is the combination of gray scale and elastogram ultrasound images.

2.
Toxicol Lett ; 321: 146-154, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31836503

RESUMO

BACKGROUND: Exposure to particulate matters (PMs) can lead to an acute exacerbation of allergic airway diseases, increasing the severity of symptoms and mortality. However, little is known about the underlying molecular mechanism. This study aimed to investigate the effects of PMs on acute exacerbation of allergic airway inflammation and seek potential therapeutic targets. METHODS: Non-allergic control and ovalbumin (OVA)-allergic wide-type (WT) and Toll-like receptor 2 knockout (Tlr2-/-) mice were exposed to 100 µg of PM (diameter 5.85 µm) or saline by the oropharyngeal instillation. The responses were examined three days after exposure. In the RAW264.7 macrophage cell line, Tlr2 was knocked down by small-interfering RNA or the NF-κB inhibitor JSH-23 was used, and then the cells were stimulated with PMs for 12 h before comparison of the inflammatory responses. RESULTS: PM exposure led to increased inflammatory cell recruitment and airway intensity of PAS + staining in OVA-allergic WT mice, accompanied with an accumulation of inflammatory cells and elevated inflammatory cytokines, such as IL-6 and IL-18, in the bronchoalveolar lavage fluid (BALF). Furthermore, the protein levels of TLR2 and the NLRP3 inflammasome were elevated concomitantly with the airway inflammation post-OVA/PMs challenge. Tlr2 deficiency effectively inhibited the airway inflammation, including pulmonary inflammatory cell recruitment, mucus secretion, serum OVA-specific immunoglobulin E (IgE), and BALF inflammatory cytokine production. Additionally, the P-induced NLRP3 activation in the RAW 264.7 cell line was diminished by the knockdown of Tlr2 or JSH-23 treatment in vitro. CONCLUSION: Our results indicated that PMs exacerbate the allergic airway inflammation mediated by the TLR2/ NF-κB/NLRP3 signaling pathway. Inhibition of NF-κB seems to be a possible treatment.


Assuntos
Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Material Particulado/toxicidade , Hipersensibilidade Respiratória/induzido quimicamente , Receptor 2 Toll-Like/metabolismo , Alérgenos , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Pulmão/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina , Tamanho da Partícula , Células RAW 264.7 , Hipersensibilidade Respiratória/genética , Hipersensibilidade Respiratória/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/deficiência , Receptor 2 Toll-Like/genética
3.
Exp Anim ; 69(1): 45-53, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31391379

RESUMO

Ip3r1 encodes an inositol 1,4,5-trisphosphate-responsive calcium channel. Mutations in the IP3R1 gene in humans may cause Gillespie syndrome (GS) typically presents as fixed dilated pupils in affected infants, which was referred to as iris hypoplasia. However, there is no report of mice with Ip3r1 heterozygous mutations showing dilated pupils. Here, we report a new Ip3r1 allele with short-term dilated pupil phenotype derived from an N-ethyl-N-nitrosourea (ENU) mutagenesis screen. This allele carries a G5927A transition mutation in Ip3r1 gene (NM_010585), which is predicted to result in a C1976Y amino acid change in the open reading frame of IP3R1 (NP_034715). We named this novel Ip3r1 allele Ip3r1C1976Y. Histology and pharmacological tests show that the dilated pupil phenotype is a mydriasis caused by the functional defect in the iris constrictor muscles in Ip3r1C1976Y. The dilated pupil phenotype in Ip3r1C1976Y was referred to as mydriasis and excluding iris hypoplasia. IHC analysis revealed increased expression of BIP protein, the master regulator of unfolded protein response (UPR) signaling, in Ip3r1C1976Y mice that did not recover. This study is the first report of an Ip3r1 mutation being associated with the mydriasis phenotype. Ip3r1C1976Y mice represent a self-healing model that may be used to study the therapeutic approach for Ip3r1-related diseases.

4.
Lancet Diabetes Endocrinol ; 8(2): 115-124, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31879247

RESUMO

BACKGROUND: National investigations on the interaction of insulin resistance, ß-cell dysfunction, and obesity with the development of diabetes are scarce in China. We aimed to investigate the individual and joint associations of insulin resistance and ß-cell dysfunction with incident diabetes, and to examine the modifying effect of BMI and waist circumference on these associations among adults with normal glucose tolerance and with prediabetes. METHODS: In this nationwide, population-based, prospective cohort study, we analysed data from the China Cardiometabolic Disease and Cancer Cohort Study, which recruited adults aged 40 years or older during 2011-12 (baseline) and invited participants to attend follow-up visits in 2014-16. Patients with diabetes at baseline, missing data for baseline measures of glucose tolerance status, missing data for baseline homoeostasis model assessment (HOMA) indexes, missing data for baseline covariates, and missing data for measures of glucose tolerance status at follow-up visits were excluded. At baseline and follow-up visits, a comprehensive set of questionnaires, clinical measurements, oral glucose tolerance tests, and laboratory examinations were carried out following standardised protocols. Glucose tolerance status and prediabetes were defined according to the American Diabetes Association 2010 criteria. In the main analysis, we examined the contributions of insulin resistance (HOMA of insulin resistance [HOMA-IR]) and ß-cell dysfunction (HOMA of ß-cell function [HOMA-B]) to diabetes risk, and evaluated the impact of obesity on these associations. FINDINGS: 94 952 participants (31 517 men and 63 435 women) were included in the analysis. High HOMA-IR was associated with a greater hazard of diabetes (quartile 4 vs 1: hazard ratio [HR] 6·70, 95% CI 6·08-7·39; per unit increase in Z score: HR 2·17, 95% CI 2·10-2·24) than low HOMA-B (quartile 1 vs 4: 4·08, 3·72-4·48; per unit decrease in Z score: 1·92, 1·85-2·00). Approximately 24·4% (95% CI 23·6-25·2) of the incident diabetes could be attributed to insulin resistance and 12·4% (11·2-13·7) could be attributed to ß-cell dysfunction. The HRs for diabetes were 1·83 (95% CI 1·72-1·95) per unit increase in Z score of HOMA-IR and 2·03 (1·86-2·21) per unit decrease in Z score of HOMA-B among participants with normal weight; the corresponding HRs for diabetes were 2·02 (1·93-2·11) and 1·88 (1·79-1·98) among participants with obesity (pinteraction=0·0091). These associations and interactions were similar for participants with normal glucose tolerance or prediabetes. INTERPRETATION: Insulin resistance shows a stronger association with incident diabetes than does ß-cell dysfunction in Chinese adults, and this association pattern was more prominent among adults with obesity. Given the limitations of HOMA indexes as surrogate measures of insulin resistance and ß-cell dysfunction, these findings should be interpreted with caution. FUNDING: National Natural Science Foundation of China.

5.
Front Oncol ; 9: 1203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799183

RESUMO

Background: To evaluate the accuracy of radiomics algorithm based on original radio frequency (ORF) signals for prospective prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) lesions. Methods: In this prospective study, we enrolled 42 inpatients diagnosed with HCC from January 2018 to December 2018. All HCC lesions were proved by surgical resection and histopathology results, including 21 lesions with MVI. Ultrasound ORF data and grayscale ultrasound images of HCC lesions were collected before operation for further radiomics analysis. Three ultrasound feature maps were calculated using signal analysis and processing (SAP) technology in first feature extraction. The diagnostic accuracy of model based on ORF signals was compared with the model based on grayscale ultrasound images. Results: A total of 1,050 radiomics features were extracted from ORF signals of each HCC lesion. The performance of MVI prediction model based on ORF was better than those based on grayscale ultrasound images. The best area under curve, accuracy, sensitivity, and specificity of ultrasound radiomics in prediction of MVI were 95.01, 92.86, 85.71, and 100%, respectively. Conclusions: Radiomics algorithm based on ultrasound ORF data combined with SAP technology can effectively predict MVI, which has potential clinical application value for non-invasively preoperative prediction of MVI in HCC patients.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31728587

RESUMO

PURPOSE: To assess the predictive power of pre-therapy 18F-FDG PET/CT-based radiomic features for epidermal growth factor receptor (EGFR) mutation status in non-small cell lung cancer. METHODS: Two hundred and forty-eight lung cancer patients underwent pre-therapy diagnostic 18F-FDG PET/CT scans and were tested for genetic mutations. The LIFEx package was used to extract 47 PET and 45 CT radiomic features reflecting tumor heterogeneity and phenotype. The least absolute shrinkage and selection operator (LASSO) algorithm was used to select radiomic features and develop a radiomics signature. We compared the predictive performance of models established by radiomics signature, clinical variables, and their combinations using receiver operating curves (ROCs). In addition, a nomogram based on the radiomics signature score (rad-score) and clinical variables was developed. RESULTS: The patients were divided into a training set (n = 175) and a validation set (n = 73). Ten radiomic features were selected to build the radiomics signature model. The model showed a significant ability to discriminate between EGFR mutation and EGFR wild type, with area under the ROC curve (AUC) equal to 0.79 in the training set, and 0.85 in the validation set, compared with 0.75 and 0.69 for the clinical model. When clinical variables and radiomics signature were combined, the AUC increased to 0.86 (95% CI [0.80-0.91]) in the training set and 0.87 (95% CI [0.79-0.95]) in the validation set, thus showing better performance in the prediction of EGFR mutations. CONCLUSION: The PET/CT-based radiomic features showed good performance in predicting EGFR mutation in non-small cell lung cancer, providing a useful method for the choice of targeted therapy in a clinical setting.

7.
Biomed Eng Online ; 18(1): 95, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511011

RESUMO

BACKGROUND: Improving imaging quality is a fundamental problem in ultrasound contrast agent imaging (UCAI) research. Plane wave imaging (PWI) has been deemed as a potential method for UCAI due to its' high frame rate and low mechanical index. High frame rate can improve the temporal resolution of UCAI. Meanwhile, low mechanical index is essential to UCAI since microbubbles can be easily broken under high mechanical index conditions. However, the clinical practice of ultrasound contrast agent plane wave imaging (UCPWI) is still limited by poor imaging quality for lack of transmit focus. The purpose of this study was to propose and validate a new post-processing method that combined with deep learning to improve the imaging quality of UCPWI. The proposed method consists of three stages: (1) first, a deep learning approach based on U-net was trained to differentiate the microbubble and tissue radio frequency (RF) signals; (2) then, to eliminate the remaining tissue RF signals, the bubble approximated wavelet transform (BAWT) combined with maximum eigenvalue threshold was employed. BAWT can enhance the UCA area brightness, and eigenvalue threshold can be set to eliminate the interference areas due to the large difference of maximum eigenvalue between UCA and tissue areas; (3) finally, the accurate microbubble imaging were obtained through eigenspace-based minimum variance (ESBMV). RESULTS: The proposed method was validated by both phantom and in vivo rabbit experiment results. Compared with UCPWI based on delay and sum (DAS), the imaging contrast-to-tissue ratio (CTR) and contrast-to-noise ratio (CNR) was improved by 21.3 dB and 10.4 dB in the phantom experiment, and the corresponding improvements were 22.3 dB and 42.8 dB in the rabbit experiment. CONCLUSIONS: Our method illustrates superior imaging performance and high reproducibility, and thus is promising in improving the contrast image quality and the clinical value of UCPWI.

8.
J Hum Hypertens ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431682

RESUMO

The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) lowered the diagnostic criteria for hypertension. We aimed to explore whether clustering of multiple risk factors are associated with the risk of new-onset hypertension defined by the 2017 ACC/AHA Hypertension Guideline. Subjects who attended ≥2 annual health examinations without baseline hypertension and cardiovascular disease were included. Hypertension was defined according to the 2017 ACC/AHA Hypertension Guideline. Seven predefined risk factors, including age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and a poor estimated glomerular filtration rate, were analyzed. A composite, individual-level, cumulative score incorporating these seven risk factors (no = 0 point; yes = 1 point; total range of 0-7 points) was calculated. The association between the cumulative score and the risk of hypertension was analyzed using a Cox regression model. A total of 4424 (21.6%) of 20,190 subjects included had new-onset hypertension during a follow-up duration of 3.6 years. Compared with subjects with 0 points, the adjusted hazard ratios (95% confidence intervals) for the development of hypertension for those with 1, 2, 3, and ≥4 points were 1.21 (1.07-1.38), 1.34 (1.19-1.52), 1.44 (1.26-1.63), and 1.64 (1.44-1.87), respectively (P < 0.001), after adjustment for sex and baseline blood pressure. Age, resting heart rate, overweight/obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and a poor estimated glomerular filtration rate are associated with an increased risk of future hypertension. When these factors are combined, there is an accumulated increase in risk.

9.
JAMA Cardiol ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31365039

RESUMO

Importance: Whether optimal cardiovascular health metrics may counteract the risk of cardiovascular events among patients with prediabetes or diabetes is unclear. Objective: To investigate the associations of ideal cardiovascular health metrics (ICVHMs) with subsequent development of cardiovascular disease (CVD) among participants with prediabetes or diabetes as compared with participants with normal glucose regulation. Design, Setting, and Participants: The China Cardiometabolic Disease and Cancer Cohort Study was a nationwide, population-based, prospective cohort study of 20 communities from various geographic regions in China. The study included 111 765 participants who were free from CVD or cancer at baseline. Data were analyzed between 2011 and 2016. Exposures: Prediabetes and diabetes were defined according to the American Diabetes Association 2010 criteria. Seven ICVHMs were adapted from the American Heart Association recommendations. Main Outcomes and Measures: The composite of incident fatal or nonfatal CVD, including cardiovascular death, myocardial infarction, stroke, and hospitalized or treated heart failure. Results: Of the 111 765 participants, 24 881 (22.3%) had normal glucose regulation, 61 024 (54.6%) had prediabetes, and 25 860 (23.1%) had diabetes. Mean (SD) age ranged from 52.9 (8.6) years to 59.4 (8.7) years. Compared with participants with normal glucose regulation, among participants with prediabetes, the multivariable-adjusted hazard ratio for CVD was 1.34 (95% CI, 1.16-1.55) for participants who had 1 ICVHM or less and 0.57 (95% CI, 0.43-0.75) for participants who had at least 5 ICVHMs; among participants with diabetes, the hazard ratios for CVD were 2.05 (95% CI, 1.76-2.38) and 0.80 (95% CI, 0.56-1.15) for participants who had 1 ICVHM or less and at least 5 ICVHMs, respectively. Such pattern of association between ICVHM and CVD was more prominent for participants younger than 55 years (prediabetes and at least 5 ICVHMs: hazard ratio [HR], 0.32; 95% CI, 0.16-0.63; 1 ICVHM or less: HR, 1.58, 95% CI, 1.13-2.21; diabetes and at least 5 ICVHMs: HR, 0.99; 95% CI, 0.44-2.26; 1 ICVHM or less: HR, 2.46; 95% CI, 1.71-3.54; compared with normal glucose regulation) than for participants 65 years or older (prediabetes and at least 5 ICVHMs: HR, 0.80; 95% CI, 0.50-1.26; 1 ICVHM or less: HR, 1.01; 95% CI, 0.79-1.31; diabetes and at least 5 ICVHMs: HR, 0.79; 95% CI, 0.46-1.35; 1 ICVHM or less: HR, 1.73; 95% CI, 1.36-2.22, compared with normal glucose regulation; P values for interaction ≤.02). Additionally, the hazard ratio for CVD per additional ICVHM was 0.82 (95% CI, 0.79-0.86) among participants with prediabetes and was 0.85 (95% CI, 0.80-0.89) among participants with diabetes. Conclusions and Relevance: Participants with prediabetes or diabetes who had 5 or more ICVHMs exhibited lower or no significant excess CVD risks compared with the participants with normal glucose regulation.

10.
BMC Surg ; 19(1): 89, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296197

RESUMO

BACKGROUNDS: The clinicopathologic features and biological behaviors of pancreatic mixed adenoneuroendocrine carcinoma (pMANEC) and its impacts on survival are poorly known. METHODS: We retrospectively reviewed seven pMANEC cases from a single institution from September 2010 to January 2017 along with twenty-one previously reported cases from the literature. Survival and prognostic analyses were conducted using Kaplan-Meier estimates and Cox regression, respectively. RESULTS: Seven pMANEC cases were identified during the study interval. Among the six patients who underwent operations, five reached R0 resections, one experienced postoperative pancreatic fistula, and two suffered other complications. The median progression-free survival (PFS) and disease-specific survival (DSS) were 7.5 months (2 to 36 months) and 15 months (6 to 36 months), respectively. A total analysis of twenty-eight pMANEC cases showed that patients were mostly older (median age, 59.5 years) and male (64.3%). The two most common symptoms were abdominal pain (53.6%) and obstructive jaundice (35.7%). The majority of pMANECs were non-functional (89.3%) and located in the pancreatic head (64.3%). The median diameter of pMANEC was 3.0 cm, with a wide range (0.5 to 19.0 cm). Lymph node metastasis (P = 0.015) was associated with decreased DSS, while age (P = 0.414), sex (P = 0.125), tumor size (P = 0.392), location (P = 0.913), functional status (P = 0.313), CA19-9 level (P = 0.608), and liver metastasis (P = 0.935) did not show significant prognoses on DSS. CONCLUSIONS: We reported seven pMANEC cases and outlined their clinical behaviors and prognoses with a review of twenty-one cases from the literature. Lymph node metastasis was found to be a negative prognostic factor of DSS based on the present study.


Assuntos
Adenocarcinoma/patologia , Carcinoma Neuroendócrino/patologia , Neoplasias Pancreáticas/patologia , Dor Abdominal/etiologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Carcinoma Neuroendócrino/cirurgia , Intervalo Livre de Doença , Feminino , Hospitais com Alto Volume de Atendimentos , Humanos , Icterícia Obstrutiva/etiologia , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos
11.
Neuroimage Clin ; 23: 101909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31284231

RESUMO

Cerebral edema after brain injury can lead to brain damage and death if diagnosis and treatment are delayed. This study investigates the feasibility of employing electrical impedance tomography (EIT) as a non-invasive imaging tool for monitoring the development of cerebral edema, in which impedance imaging of the brain related to brain water content is compared with intracranial pressure (ICP). We enrolled forty patients with cerebral hemorrhage who underwent lateral external ventricular drain with intraventricular ICP and EIT monitoring for 3 h after initiation of dehydration treatment. The average reconstructed impedance value (ARV) calculated from EIT images was compared with ICP. Dehydration effects induced changes in ARV and ICP showed a close negative correlation in all patients, and the mean correlation reached R2 = 0.78 ±â€¯0.16 (p < .001). A regression equation (R2 = 0.62, p < .001) was formulated from the total of measurement data. The 95% limits of agreement were - 6.13 to 6.13 mmHg. Adaptive clustering and variance analysis of normalized changes in ARV and ICP showed 92.5% similarity and no statistically significant differences (p > .05). Moreover, the sensitivity, specificity and area under the curve of changes in ICP >10 mmHg were 0.65, 0.73 and 0.70 respectively. The findings show that EIT can monitor changes in brain water content associated with cerebral edema, which could provide a real-time and non-invasive imaging tool for early identification of cerebral edema and the evaluation of mannitol dehydration.

12.
Nat Prod Res ; : 1-6, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315445

RESUMO

Chemical investigation of Lansium domesticum has led to the isolation of two undescribed compounds, namely 17(20)E-dyscusin B (1) and 17(20)Z-dyscusin B (2), as well as three known ones (3 - 5). Structural elucidation was accomplished by the analysis of NMR, MS and IR data. Compounds 1 and 2 were a pair of Δ17(20) geometric isomers of pregnane steroids and showed the significant nitric oxide (NO) inhibitory activities.

13.
Biomed Eng Online ; 18(1): 84, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358013

RESUMO

BACKGROUND: Electrical impedance tomography (EIT) is a noninvasive, radiation-free, and low-cost imaging modality for monitoring the conductivity distribution inside a patient. Nowadays, time-difference EIT (tdEIT) is used extensively as it has fast imaging speed and can reflect the dynamic changes of diseases, which make it attractive for a number of medical applications. Moreover, modeling errors are compensated to some extent by subtraction of voltage measurements collected before and after the change. However, tissue conductivity varies with frequency and tdEIT does not efficiently exploit multi-frequency information as it only uses measurements associated with a single frequency. METHODS: This paper proposes a tdEIT algorithm that imposes spectral constraints on the framework of the linear least squares problem. Simulation and phantom experiments are conducted to compare the proposed spectral constraints algorithm (SC) with the damped least squares algorithm (DLS), which is a stable tdEIT algorithm used in clinical practice. The condition number and rank of the matrices needing inverses are analyzed, and image quality is evaluated using four indexes. The possibility of multi-tissue imaging and the influence of spectral errors are also explored. RESULTS: Significant performance improvement is achieved by combining multi-frequency and time-difference information. The simulation results show that, in one-step iteration, both algorithms have the same condition number and rank, but SC effectively reduces image noise by 20.25% compared to DLS. In addition, deformation error and position error are reduced by 8.37% and 7.86%, respectively. In two-step iteration, the rank of SC is greatly increased, which suggests that more information is employed in image reconstruction. Image noise is further reduced by an average of 32.58%, and deformation error and position error are also reduced by 20.20% and 31.36%, respectively. The phantom results also indicate that SC has stronger noise suppression and target identification abilities, and this advantage is more obvious with iteration. The results of multi-tissue imaging show that SC has the unique advantage of automatically extracting a single tissue to image. CONCLUSIONS: SC enables tdEIT to utilize multi-frequency information in cases where the spectral constraints are known and then provides higher quality images for applications.


Assuntos
Algoritmos , Tomografia/métodos , Impedância Elétrica , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Fatores de Tempo
14.
World J Gastroenterol ; 25(20): 2514-2523, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31171894

RESUMO

BACKGROUND: Pancreatic fistula is one of the most serious complications after pancreatoduodenectomy for treating any lesions at the pancreatic head. For years, surgeons have tried various methods to reduce its incidence. AIM: To investigate and emphasize the clinical outcomes of Blumgart anastomosis compared with traditional anastomosis in reducing postoperative pancreatic fistula. METHODS: In this observational study, a retrospective analysis of 291 patients who underwent pancreatoduodenectomy, including Blumgart anastomosis (201 patients) and traditional embedded pancreaticojejunostomy (90 patients), was performed in our hospital. The preoperative and perioperative courses and long-term follow-up status were analyzed to compare the advantages and disadvantages of the two methods. Moreover, 291 patients were then separated by the severity of postoperative pancreatic fistula, and two methods of pancreaticojejunostomy were compared to detect the features of different anastomosis. Six experienced surgeons were involved and all of them were proficient in both surgical techniques. RESULTS: The characteristics of the patients in the two groups showed no significant differences, nor the preoperative information and pathological diagnoses. The operative time was significantly shorter in the Blumgart group (343.5 ± 23.0 vs 450.0 ± 40.1 min, P = 0.028), as well as the duration of pancreaticojejunostomy drainage tube placement and postoperative hospital stay (12.7 ± 0.9 d vs 17.4 ± 1.8 d, P = 0.031; and 21.9 ± 1.3 d vs 28.9 ± 1.3 d, P = 0.020, respectively). The overall complications after surgery were much less in the Blumgart group than in the embedded group (11.9% vs 26.7%, P = 0.002). Patients who underwent Blumgart anastomosis would suffer less from severe pancreatic fistula (71.9% vs 50.0%, P = 0.006), and this pancreaticojejunostomy procedure did not have worse influences on long-term complications and life quality. Thus, Blumgart anastomosis is a feasible pancreaticojejunostomy procedure in pancreatoduodenectomy surgery. It is safe in causing less postoperative complications, especially pancreatic fistula, and thus shortens the hospitalization duration. CONCLUSION: Surgical method should be a key factor in reducing pancreatic fistula, and Blumgart anastomosis needs further promotion.


Assuntos
Fístula Pancreática/epidemiologia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Pancreaticojejunostomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pâncreas/cirurgia , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Pancreaticoduodenectomia/métodos , Pancreaticojejunostomia/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento
15.
Diabetes Care ; 42(8): 1539-1548, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152120

RESUMO

OBJECTIVE: Uncertainty remains regarding the predictive value of various glycemic measures as they relate to the risk of diabetes and its complications. Using the cutoffs recommended by the American Diabetes Association's 2010 criteria, we determined the associations of fasting plasma glucose (FPG), 2-h postload glucose (2h-PG), and HbA1c with the outcomes. RESEARCH DESIGN AND METHODS: Baseline medical history, FPG, 2h-PG, and HbA1c were obtained from a population-based cohort of 193,846 adults aged ≥40 years in China during 2011-2012. A follow-up visit was conducted during 2014-2016 in order to assess incident diabetes, cardiovascular disease (CVD), cancer, and mortality. RESULTS: We documented 8,063 cases of diabetes, 3,014 CVD-related events, 1,624 cases of cancer, and 2,409 deaths during up to 5 years of follow-up. Multivariable-adjusted risk ratios (95% CIs) of diabetes associated with prediabetes based on FPG of 100-125 mg/dL, 2h-PG of 140-199 mg/dL, or HbA1c of 5.7-6.4% (39-47 mmol/mol) were 1.60 (1.43-1.79), 2.72 (2.43-3.04), and 1.49 (1.36-1.62), respectively. Restricted cubic spline analyses suggested J-shaped associations of FPG, 2h-PG, and HbA1c levels with CVD, cancer, and mortality. Multivariable-adjusted hazard ratios (95% CIs) associated with untreated diabetes based on FPG ≥126 mg/dL, 2h-PG ≥200 mg/dL, or HbA1c ≥6.5% (48 mmol/mol) were 1.18 (1.05-1.33), 1.31 (1.18-1.45), and 1.20 (1.07-1.34) for CVD; 1.10 (0.92-1.32), 1.44 (1.25-1.67), and 1.08 (0.92-1.28) for cancer; and 1.37 (1.20-1.57), 1.57 (1.41-1.76), and 1.33 (1.17-1.52) for mortality, respectively. 2h-PG remained significantly associated with outcomes in models including FPG and HbA1c as spline terms. Furthermore, 2h-PG significantly improved the ability of the C statistic to predict diabetes, CVD, and mortality. CONCLUSIONS: 2h-PG remains independently predictive of outcomes in models including FPG and HbA1c. Therefore, in addition to FPG and HbA1c, routine testing of 2h-PG should be considered in order to better assess the risks of outcomes.

16.
Med Biol Eng Comput ; 57(9): 1917-1931, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250276

RESUMO

Electrical impedance tomography (EIT) is a non-invasive and real-time imaging method that has the potential to be used for monitoring intracerebral hemorrhage (ICH). Recent studies have proposed that ischemia secondary to ICH occurs simultaneously in the brain. Real-time monitoring of the development of hemorrhage and risk of secondary ischemia is crucial for clinical intervention. However, few studies have explored the performance of EIT monitoring in cases where hemorrhage and secondary ischemia exist. When these lesions get close to each other, or their conductivity and volume changes differ greatly, it becomes challenging for dynamic EIT algorithms to simultaneously reconstruct subtle injuries. To address this, an iterative damped least-squares (IDLS) algorithm is proposed in this study. The quality of the IDLS algorithm was assessed using blur radius and temporal response during computer simulation and a phantom 3D head-shaped model where bidirectional disturbance targets were simulated. The results showed that the IDLS algorithm enhanced contrast and concurrently reconstructed bidirectional disturbance targets in images. Moreover, it showed superior performance in decreasing the blur radius and was time cost-effective. With further improvement, the IDLS algorithm has the potential to be used for monitoring the development of hemorrhage and risk of ischemia secondary to ICH. Graphical abstract (a) and (b) are simulation images of bidirectional disturbance targets with different change ratios of volume (Vr) and conductivity (σr) based on the damped least-squares (DLS) algorithm and iterative damped least-squared (IDLS) algorithm, respectively. (c) shows the performance metrics of blur radius and temporal response with different volume ratio (corresponding to Vr). (d) shows the performance metrics of blur radius and temporal response with different conductivity change percentage (corresponding to σr).


Assuntos
Algoritmos , Lesões Encefálicas/patologia , Isquemia Encefálica/patologia , Hemorragias Intracranianas/patologia , Monitorização Fisiológica/métodos , Lesões Encefálicas/complicações , Simulação por Computador , Impedância Elétrica , Humanos , Processamento de Imagem Assistida por Computador/métodos , Análise dos Mínimos Quadrados , Imagens de Fantasmas , Tomografia Computadorizada por Raios X
17.
Biomed Environ Sci ; 32(4): 260-271, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31217062

RESUMO

OBJECTIVE: Ideal cardiovascular health (CVH) could predict a lower risk of developing cardiovascular diseases. This study was conducted to investigate the association between ideal CVH and subclinical atherosclerosis in a population cohort of Chinese adults aged ⪖ 40 years. METHODS: This study was designed as a cross-sectional analysis of 8,395 participants who had complete data at baseline and a prospective analysis of 4,879 participants who had complete data at 4.3 years of follow-up. Ideal CVH metrics were defined according to the American Heart Association. Subclinical atherosclerosis was evaluated by plaques in carotid arteries, carotid intima-media thickness (CIMT), brachial-ankle pulse wave velocity (baPWV), and urinary albumin-to-creatinine ratio (UACR). RESULTS: Both the prevalence and incidence of atherosclerosis measures were found to be decreased with increasing numbers of ideal CVH metrics at baseline (all P values for trend < 0.01). The levels of CIMT and UACR at follow-up showed an inverse and significant association with the numbers of ideal CVH metrics at baseline (both P values for trend < 0.05) but a borderline significant association with baPWV (P for trend = 0.0505). Taking participants with 0-1 ideal metric as reference, we found that participants with 5-6 ideal metrics had significantly lower risks of developing carotid plaques (odds ratio, OR = 0.46; 95% confidence interval, CI 0.27-0.79), increased CIMT (OR = 0.60; 95% CI 0.42-0.84), and increased baPWV (OR = 0.57; 95% CI 0.34-0.97) after full adjustments. A significant interactive effect of age and CVH was detected on CIMT and baPWV progression (both P values for interaction < 0.05). CONCLUSION: The numbers of ideal CVH metrics showed a significant and inverse association with the risk of developing subclinical atherosclerosis in middle-aged and elderly Chinese adults, whereas its dose-response effect was attenuated in individuals aged ≥ 60 years and partially weakened in male participants.


Assuntos
Aterosclerose/epidemiologia , Nível de Saúde , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
Biomed Eng Online ; 18(1): 55, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072348

RESUMO

BACKGROUND: Head movement interferences are a common problem during prolonged dynamic brain electrical impedance tomography (EIT) clinical monitoring. Head movement interferences mainly originate from body movements of patients and nursing procedures performed by medical staff, etc. These body movements will lead to variation in boundary voltage signals, which affects image reconstruction. METHODS: This study employed a data preprocessing method based on wavelet decomposition to inhibit head movement interferences in brain EIT data. Mixed Gaussian models were applied to describe the distribution characteristics of brain EIT data. We identified head movement signal through the differences in distribution characteristics of corresponding wavelet decomposition coefficients between head movement artifacts and normal signals, and then managed the contaminated data with improved on-line wavelet processing methods. RESULTS: To validate the efficacy of the method, simulated signal experiments and human data experiments were performed. In the simulation experiment, the simulated movement artifact was significantly reduced and data quality was improved with indicators' increase in PRD and correlation coefficient. Human data experiments demonstrated that this method effectively suppressed head movement in signals and reduce artifacts resulting from head movement artifacts in images. CONCLUSION: In this paper, we proposed an on-line strategy to manage the head movement interferences from the brain EIT data based on the distribution characteristics of wavelet coefficients. Our strategy is capable of reducing the movement interference in the data and improving the reconstructed images. This work would improve the clinical practicability of brain EIT and contribute to its further promotion.


Assuntos
Artefatos , Encéfalo/diagnóstico por imagem , Movimentos da Cabeça , Processamento de Imagem Assistida por Computador/métodos , Tomografia , Análise de Ondaletas , Impedância Elétrica , Humanos , Imagens de Fantasmas
19.
Bioprocess Biosyst Eng ; 42(5): 853-866, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30963243

RESUMO

Excess inorganic nitrogen in water poses a severe threat to enviroment. Removal of inorganic nitrogen by heterotrophic nitrifying-aerobic denitrifying microorganism is supposed to be a promising and applicable technology only if the removal rate can be maintained sufficiently high in real wastewater under various conditions, such as high concentration of salt and wide range of different nitrogen concentrations. Here, a new heterotrophic nitrifying-aerobic denitrifying bacterium was isolated and named as Pseudomonas mendocina TJPU04, which removes NH4+-N, NO3--N and NO2--N with average rate of 4.69, 5.60, 4.99 mg/L/h, respectively. It also maintains high nitrogen removal efficiency over a wide range of nitrogen concentrations. When concentration of NH4+-N, NO3--N and NO2--N was up to 150, 150 and 50 mg/L, 98%, 93%, and 100% removal efficiency could be obtained, respectively, after 30-h incubation under sterile condition. When it was applied under non-sterile condition, the ammonia removal efficiency was slightly lower than that under sterile condition. However, the nitrate and nitrite removal efficiencies under non-sterile condition were significantly higher than those under sterile condition. Strain TJPU04 also showed efficient nitrogen removal performance in the presence of high concentration of salt and nitrogen. In addition, the removal efficiencies of NH4+-N, NO3--N and TN in real wastewater were 91%, 52%, and 75%, respectively. These results suggest that strain TJPU04 is a promising candidate for efficient removal of inorganic nitrogen in wastewater treatment.


Assuntos
Desnitrificação/fisiologia , Nitrificação/fisiologia , Pseudomonas mendocina/metabolismo , Amônia/metabolismo , Biodegradação Ambiental , Nitratos/metabolismo , Nitrogênio/metabolismo
20.
J Hypertens ; 37(4): 696-701, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30817449

RESUMO

OBJECTIVES: This study aimed to develop a cumulative score composed of seven risk factors: age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and impaired estimated glomerular filtration rate (eGFR), to evaluate the risk of new-onset hypertension. METHODS: We retrospectively conducted a cohort study in 23 665 participants free from hypertension at baseline, who attended at least two annual health examinations between 2011 and 2016. We defined hypertension as SBP of 140 mmHg or less and/or DBP of at least 90 mmHg, according to the 2010 Chinese guidelines for the management of hypertension. We computed a composite, individual-level cumulative score incorporating all seven risk factors (no = 0 point; yes = 1 point; total range 0-7 points). Cox regression was used to analyze the association between cumulative score and risk of hypertension. RESULTS: A total of 2305 participants developed hypertension during a median follow-up period of 3.6 years. Compared with participants with 0 points, the adjusted hazard ratios (95% confidence intervals) for the development of hypertension for those with 2, 3, and at least 4 points were 1.61 (1.29-2.02), 2.05 (1.64-2.57) and 2.77 (2.22-3.46), respectively (P trend < 0.001). This association was present after adjustment for sex and baseline blood pressure. CONCLUSION: Age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and impaired eGFR were associated with significant risk of new-onset hypertension and when combined there was an accumulation of risk.

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