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1.
Food Chem ; 359: 129960, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33945987

RESUMO

The interaction between lipase and quercetin 3-rhamnoside was studied by fluorescence spectroscopy, enzyme kinetics, and molecular dynamics simulation. The results showed that quercetin 3-rhamnoside had a strong quenching effect on the intrinsic fluorescence of lipase. The binding constant decreased with increasing temperature, and the number of binding sites approached 1. Thermodynamic parameters indicated that hydrogen bonding and van der Waals forces are the dominant forces when the interaction occurs. Circular dichroism spectroscopy and infrared spectroscopy proved that the ligand perturbed the structure of lipase. Enzyme kinetics results showed that quercetin 3-rhamnoside inhibited lipase, and the inhibitory effect was dose-dependent. Molecular dynamics simulation further explained the interaction mechanism and inhibitory effect. This study confirmed the inhibitory effect of quercetin 3-rhamnoside on lipase explained their binding mechanism, which will contribute to guiding the development of fat-reducing functional foods.

2.
Int J Biol Macromol ; 183: 490-501, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33957197

RESUMO

The wingless-type MMTV integration site family member-4 (Wnt4), a member of the wingless-related integration site (Wnt) family, is widely accepted as a key regulator of ovarian development in mammals. In this study, a full-length cDNA of Wnt4 (designated as Sp-Wnt4) was cloned, characterized, and functionally studied in mud crab (Scylla paramamosain). The full-length cDNA of Sp-Wnt4 consists of 2659 bp with an open reading frame (ORF) encoding 359 amino acids, a 907 bp 5'-UTR and a 672 bp 3'-UTR. Sp-Wnt4 contains 25 cysteine (Cys) residues and three potential N-glycosylation sites. Sp-Wnt4 protein shared the highest identity (98.9%) to the Wnt4 protein of Portunus trituberculatus. The phylogenetic tree showed that Sp-Wnt4 and Wnt4 protein of Malacostracan crustaceans clustered together, indicating that they had a close genetic distance. Sp-Wnt4 was expressed at a higher level in the ovary compared to other tissues, with the highest expression level at the third stage (O-III) of the ovarian development (P < 0.05). A downward trend was observed in the expression level of Sp-Wnt4 from the embryo stage to crablet stages (P < 0.05). After unilateral eyestalk ablation, the expression level of Sp-Wnt4 significantly increased in testis (14-fold) and downregulated (3.1-fold) in the gill (P < 0.05) of females. In situ hybridization (ISH) assay revealed that Sp-Wnt4 transcripts were mainly localized in the cytoplasm of oocyte cells. These findings showed that Sp-Wnt4 play crucial roles in the ovarian development of S. paramamosain. In conclusion, our study provides novel insights into the evolution and roles of the Wnt4 gene.

3.
J Food Sci ; 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33948957

RESUMO

The objective of this research was to identify and characterize the chemical compounds that exhibited monosodium glutamate (MSG)-like taste in the hydrolyzed bone meal produced by using flavourzyme. The free amino acids and peptides in the bone meal hydrolysate were analyzed. The results showed that the glutamic acid and the aspartic acid in the bone meal increased by 13.1 times and 14.2 times, respectively, after the flavourzyme hydrolysis. The peptides' isolation identified six MSG-like peptides in the hydrolysate, including APGPVGPAG, DAINWPTPGEIAH, FLGDEETVR, GVDEATIIEILTK, PAGPVGPVG, and VAPEEHPTL, which should contribute to the taste. The human sensory evaluation results indicated that the six peptides showed MSG-like taste, and the electronic tongue analysis indicated that the six peptides showed sourness, saltiness, bitterness, and astringency. The findings of this study demonstrated that the MSG-like taste of the bone meal hydrolysate should be attributed to the generation of MSG-like amino acids and peptides from the flavourzyme hydrolysis. PRACTICAL APPLICATION: The manuscript describes the umami compounds in the bone meal hydrolysate. The findings from this study should further confirm the feasibility of using bone meal to prepare meat-flavor essence and provide a better understanding of preparing bio-source flavoring peptides, which is very important to the artificial meat development and gene breeding.

4.
J Biomed Inform ; : 103799, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33965638

RESUMO

Recognition of biomedical entities from literature is a challenging research focus, which is the foundation for extracting a large amount of biomedical knowledge existing in unstructured texts into structured formats. Using the sequence labeling framework to implement biomedical named entity recognition (BioNER) is currently a conventional method. This method, however, often cannot take full advantage of the semantic information in the dataset, and the performance is not always satisfactory. In this work, instead of treating the BioNER task as a sequence labeling problem, we formulate it as a machine reading comprehension (MRC) problem. This formulation can introduce more prior knowledge utilizing well-designed queries, and no longer need decoding processes such as conditional random fields (CRF). We conduct experiments on six BioNER datasets, and the experimental results demonstrate the effectiveness of our method. Our method achieves state-of-the-art (SOTA) performance on the BC4CHEMD, BC5CDR-Chem, BC5CDR-Disease, NCBI-Disease, BC2GM and JNLPBA datasets, achieving F1-scores of 92.92%, 94.19%, 87.83%, 90.04%, 85.48% and 78.93%, respectively.

5.
Indoor Air ; 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33969921

RESUMO

In this paper, a three-dimensional non-isothermal computational model for predicting indoor SVOC distribution is proposed, considering the effects of turbulence diffusion and suspended particles. The realizable k-ε model is introduced for turbulent flow simulation in a room. The Euler-Euler method is adopted to deal with the gas-particle two-phase flow coupled problem. Inertia slip velocity and irreversible first-order absorption boundary are employed for more accurate prediction of particle motion. The simulated curve of outlet gas-phase di-2-ethylhexyl phthalate (DEHP) concentration with emission time is verified by available experimental data. The emission process of DEHP in a 15 m2 room in Beijing during 100 days with or without air cleaner is simulated by the developed model considering air leak through window and door gaps. It is found that if the air cleaner keeps on all the time during 100 days the gas-phase DEHP concentration in the room will tend to be uniform, while the emission process is far from equilibrium without an air cleaner even the emission lasts 100 days. Results also suggest that floor heating, decrease of particle concentration, weaken of heat transfer, enhancement of mass transfer, and air infiltration in window gap contribute to decrease DEHP concentration.

6.
Mol Hum Reprod ; 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33944929

RESUMO

Oocyte IVM technology is an option for fertility preservation in some groups of patients, such as those with polycystic ovary syndrome, patients with ovarian hyperstimulation syndrome, and for patients with cancer. However, the developmental potential of oocytes from IVM still needs to improve. Several previous studies have reported that lysophosphatidic acid (LPA) promotes glucose metabolism, cumulus cell (CC) expansion, and oocyte nuclear maturation. However, the effect of LPA on oocyte cytoplasmic maturation, particularly mitochondrial function, has rarely been studied and the underlying mechanism is largely unknown, which impedes (pre)clinical applications of LPA. In this study, cumulus-oocyte complexes (COCs) and cumulus-denuded germinal vesicle oocytes (DOs) were treated with various concentrations of LPA during IVM, in the presence or absence of the oxidative stressor cyclophosphamide (CTX). In both normal and CTX-damaged COCs, the 25 µM LPA group exhibited improved CC expansion capacity, a higher nuclear maturation rate, and superior mitochondrial function, compared to no LPA treatment. When the concentration of LPA was over 40 µM, detrimental effects of LPA on oocyte maturation occurred. Compared with COCs, the addition of LPA slightly improved oocyte nuclear and cytoplasmic maturation of DOs, but this was not statistically significant. We observed that LPA promotes the activation of ERK1/2, although this was not statistically significant in DOs. Furthermore, LPA could not reverse the negative effect of CC expansion and mitochondrial function after inactivation of ERK1/2 by U0126. RNA-Sequencing and RT-PCR results showed that LPA upregulated several ERK1/2 downstream genes related to CC expansion, such as Areg, Cited4, and Ptgs2. This study demonstrates that LPA improves oocyte quality during IVM through the activation of ERK1/2 pathway CCs and oocytes, which provides evidence for the potential addition of LPA to IVM medium.

7.
Biomed Res Int ; 2021: 5597155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33937400

RESUMO

Background: It is hard to differentiate transient symptoms associated with infarction (TSI) from transient ischemic stroke (TIA) without MRI in the early onset. However, they have distinct clinical outcomes and respond differently to therapeutics. Therefore, we aimed to develop a risk prediction model based on the clinical features to identify TSI. Methods: We enrolled 230 consecutive patients with transient neurologic deficit in the Department of Neurology, Tongji University Affiliated Tenth People's Hospital from March 2014 to October 2019. All the patients were assigned into TIA group (DWI-negative) or TSI group (DWI-positive) based on MRI conducted within five days of onset. We summarized the clinical characteristics of TSI by univariate and multivariate analyses. And then, we developed and validated a nomogram to identify TSI by the logistic regression equation. Results: Of the 230 patients, 41.3% were diagnosed with TSI. According to the multivariate analysis, four independent risk factors, including smoking history, low-density lipoprotein cholesterol, brain natriuretic peptide precursor, and ABCD3 score, were incorporated into a nomogram. We developed a predictive model named ABCD3-SLOPE. The calibration curve showed good agreement between nomogram prediction and observation. The concordance index (C-index) of the nomogram for TSI prediction was 0.77 (95% confidence interval, 0.70-0.83), and it was well-calibrated. Conclusions: Smoking history, low-density lipoprotein cholesterol, brain natriuretic peptide precursor, and ABCD3 score were reliable risk factors for TSI. ABCD3-SLOPE was a potential tool to quantify the likelihood of TSI.

8.
Zootaxa ; 4951(2): zootaxa.4951.2.2, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33903401

RESUMO

The gecko species Gekko (Japonigekko) subpalmatus was previously recorded with a relatively wide distribution from eastern, southern, and southeastern China. However, the populations in southern China are currently recognized as another valid species G. (J.) melli. In this study, we conduct a detailed morphological examination and phylogenetic analysis of the populations currently treated as G. (J.) subpalmatus or G. (J.) melli, which are collectively designated as the G. (J.) subpalmatus complex. Our results reveal that the G. (J.) subpalmatus complex comprises three evolutionarily independent taxa. The populations from Zhejiang, eastern China are G. (J.) subpalmatus, those from southern China are G. (J.) melli, while those from the Sichuan Basin, southwestern China represent a cryptic species, Gekko (Japonigekko) cib sp. nov.. Gekko (Japonigekko) cib sp. nov. can be distinguished from all congeners, by its divergence from other complex members in the CYTB and 16S genes, and a combination of morphological characteristics, especially in hemipenial morphology. Historic records of G. (J.) subpalmatus complex are also reviewed.

9.
Micromachines (Basel) ; 12(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808563

RESUMO

Overhang provides a simple but effective way of coupling (sub)structures, which has been widely adopted in the applications of optomechanics, electromechanics, mass sensing resonators, etc. Despite its simplicity, an overhanging structure demonstrates rich and complex dynamics such as mode splitting, localization and eigenfrequency veering. When an eigenfrequency veering occurs, two eigenfrequencies are very close to each other, and the error associated with the numerical discretization procedure can lead to wrong and unphysical computational results. A method of computing the eigenfrequency of two overhanging beams, which involves no numerical discretization procedure, is analytically derived. Based on the method, the mode localization and eigenfrequency veering of the overhanging beams are systematically studied and their variation patterns are summarized. The effects of the overhang geometry and beam mechanical properties on the eigenfrequency veering are also identified.

10.
Arch Gynecol Obstet ; 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33856541

RESUMO

OBJECTIVE: This study aimed to investigate the effect of ultrasound-diagnosed adenomyosis on assisted pregnancy outcomes, i.e., in vitro fertilization-embryo transfer (IVF-ET). METHODS: This was a retrospective cohort study of 18,568 women who had received their first frozen-thawed ET cycle in Center of Reproductive Medicine, Children's Hospital of Shanxi and Women Health Center of Shanxi and the Reproductive Medicine Center of Tianjin Central Obstetrics and Gynecology Hospital from January 2014 to May 2019. A total of 5,087 patients met the inclusion and exclusion criteria, and they were divided into two groups: adenomyosis with tubal factor infertility (study group, n = 193) and only tubal factor infertility (control group, n = 4894). After a 1:1 propensity score match (caliper value = 0.005), 360 cases were matched in the end. RESULT: There was no statistical difference in the embryo implantation rate, clinical pregnancy rate, or multiple pregnancy rate between the two groups (28.4% vs. 31.7%, 42.2% vs. 42.8%, and 11.7% vs. 12.8%, respectively; P > 0.05). However, the early miscarriage rate in the adenomyosis group was significantly higher than that in the control group (13.3% vs. 5.6%, respectively; P = 0.012). The live birth rate was 22.8% in the women with adenomyosis and was observed to be significantly lower than 33.3% in the control group (P = 0.026). The patients with adenomyosis had a higher incidence of pregnancy complications than those without (4.4% vs. 0.6%, respectively; P = 0.018), but the neonatal birth weight was not related to adenomyosis. CONCLUSION: Women with adenomyosis should be treated as being at high risk of early miscarriage. However, maternal adenomyosis has no effect on the birth weight of the newborn.

11.
Ann Palliat Med ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33832303

RESUMO

BACKGROUND: Oligomenorrhea is one of the most frequent gynecologic complaints that interferes with women's life quality. Treatment using traditional Chinese medicine (TCM) is a preferred alternative therapy for oligomenorrhea. However, systematic reviews (SRs) evaluating the efficacy of TCM treatments for oligomenorrhea remain absent. The present SR and meta-analysis aimed to evaluate the efficacy and safety of TCM treatment for oligomenorrhea. METHODS: Randomized controlled trials (RCTs) published in English and Chinese were retrieved by searching in the databases in October 2019, including PubMed, Cochrane Library, EMBASE, Sinomed, CNKI, VIP, and WanFang databases. Quantitative analyses and quality assessments were then conducted based on abstracted data. This study protocol is registered PROSPERO, number CRD42018095660. RESULTS: A total of 26 eligible RCTs involving 2,389 patients were included in our analysis. Overall, we observed an effect of increasing menstrual blood volumes owing to using TCM treatments plus bio-medicine (BM) (n=649; MD, 12.05; 95% CI: 5.23 to 18.87; P<0.00001; I2 =96%). Besides, TCM combined with BM yielded a significant prolongation in menstrual periods (MD, 1.20; 95% CI: 0.78 to 1.62; P<0.00001; I 2 =76%), and had potential improvements on enhancing effectiveness rates, increasing endometrial thickness, and raising the levels of estradiol (E2) and progesterone (P). Concerning adverse events (AEs), no significant difference was found in either group. The quality of evidence was relatively low. CONCLUSIONS: This study seems to support the potential effect of TCM on treating oligomenorrhea. However, the relatively low quality of prior studies calls for future RCTs to further assess the efficacy of TCM on treating oligomenorrhea using rigorous designs.

12.
J Cell Mol Med ; 25(9): 4183-4194, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33837646

RESUMO

Plexin D1 (PLXND1), which was previously thought to mediate semaphorin signalling, belongs to the Plexin family of transmembrane proteins. PLXND1 cooperates mostly with the coreceptor neuropilin and participates in many aspects of axonal guidance. PLXND1 can also act as both a tumour promoter and a tumour suppressor. Emerging evidence suggests that mutations in PLXND1 or Semaphorin 3E, the canonical ligand of PLXND1, can lead to serious cardiovascular diseases, such as congenital heart defects, CHARGE syndrome and systemic sclerosis. Upon ligand binding, PLXND1 can act as a GTPase-activating protein (GAP) and modulate integrin-mediated cell adhesion, cytoskeletal dynamics and cell migration. These effects may play regulatory roles in the development of the cardiovascular system and disease. The cardiovascular effects of PLXND1 signalling have gradually been elucidated. PLXND1 was recently shown to detect physical forces and translate them into intracellular biochemical signals in the context of atherosclerosis. Therefore, the role of PLXND1 in cardiovascular development and diseases is gaining research interest because of its potential as a biomarker and therapeutic target. In this review, we describe the cardiac effects, vascular effects and possible molecular mechanisms of PLXND1 signalling.

13.
Am J Emerg Med ; 47: 217-222, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33906128

RESUMO

OBJECTIVE: To determine if differences in patient characteristics, treatments, and outcomes exist between children with sepsis who arrive by emergency medical services (EMS) versus their own mode of transport (self-transport). METHODS: Retrospective cohort study of patients who presented to the Emergency Department (ED) of two large children's hospitals and treated for sepsis from November 2013 to June 2017. Presentation, ED treatment, and outcomes, primarily time to first bolus and first parental antibiotic, were compared between those transported via EMS versus patients who were self-transported. RESULTS: Of the 1813 children treated in the ED for sepsis, 1452 were self-transported and 361 were transported via EMS. The EMS group were more frequently male, of black race, and publicly insured than the self-transport group. The EMS group was more likely to have a critical triage category, receive initial care in the resuscitation suite (51.9 vs. 22%), have hypotension at ED presentation (14.4 vs. 5.4%), lactate >2.0 mmol/L (60.6 vs. 40.8%), vasoactive agents initiated in the ED (8.9 vs. 4.9%), and to be intubated in the ED (14.4 vs. 2.8%). The median time to first IV fluid bolus was faster in the EMS group (36 vs. 57 min). Using Cox LASSO to adjust for potential covariates, time to fluids remained faster for the EMS group (HR 1.26, 95% CI 1.12, 1.42). Time to antibiotics, ICU LOS, 3- or 30-day mortality rates did not differ, yet median hospital LOS was significantly longer in those transported by EMS versus self-transported (6.5 vs. 5.3 days). CONCLUSIONS: Children with sepsis transported by EMS are a sicker population of children than those self-transported on arrival and had longer hospital stays. EMS transport was associated with earlier in-hospital fluid resuscitation but no difference in time to first antibiotic. Improved prehospital recognition and care is needed to promote adherence to both prehospital and hospital-based sepsis resuscitation benchmarks.

14.
Exp Cell Res ; 404(1): 112580, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33811903

RESUMO

Breast cancer has been identified as the most common malignant tumors among women and the morbidity of breast cancer is still increasing rapidly. MEX3A possesses important functions in the regulation of mRNAs and may be involved in a variety of human diseases including cancer, whose relationship with breast cancer is still not clear. In this study, MEX3A was identified as a potential promotor in breast cancer, whose expression was strongly higher in breast cancer tissues than normal tissues. The in vitro experiments showed that MEX3A is capable of promoting the development of breast cancer through stimulating cell proliferation, inhibiting cell apoptosis, arresting cell cycle and promoting cell migration. The functions of MEX3A were also verified in vivo. Furthermore, a combination of genechip analysis and Ingenuity pathway analysis (IPA) identified PIK3CA as a potential downstream target of MEX3A, knockdown of which executes similar inhibitory effects on breast cancer and could alleviate MEX3A-induced progression of breast cancer. In conclusion, our study unveiled, as the first time, MEX3A as a tumor promotor for breast cancer, whose function was carried out probably through the regulation of PIK3CA.

15.
Neurosci Lett ; 753: 135870, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33812933

RESUMO

Autophagy is a highly conserved degradative process that has been associated with a number of neurological diseases. Autophagy-related protein 5 (ATG5) is one of the key genes for the regulation of the autophagy pathway. In this study, we investigated the potential relationship between ATG5 gene polymorphisms and epilepsy in Han Chinese population. We enrolled 112 patients with epilepsy and 100 healthy controls and detected the genotypic and allelic data of 6 single nucleotide polymorphisms (SNPs) in ATG5 (rs2245214, rs510432, rs548234, rs573775, rs6568431 and rs6937876). The associations of 6 SNPs and epilepsy were evaluated. The results revealed the genotypes of overdominant of rs510432 between controls and patients showed significant differences (Poverdominant = 0.003). Subgroup analysis showed a highly significant association of rs510432 with late-onset epilepsy (Poverdominant = 0.006), and rs548234 were associated with the susceptibility to temporal lobe epilepsy (Pcodominant = 0.002, Poverdominant = 0.006). Furthermore, ATG5 was not linked to either early-onset epilepsy or drug-resistant epilepsy (p > 0.0083). These results demonstrated an association of an ATG5 gene variant with epilepsy, and stronger associations with several subgroups of epilepsy were identified. Our study may provide novel evidence for the role of ATG5 in epilepsy, and contribute to our understanding of the molecular mechanisms of this chronic neurological disease.

16.
J Biomed Nanotechnol ; 17(1): 18-36, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33653494

RESUMO

Multidrug resistance (MDR) is a key to the ineffectiveness of hepatocellular carcinoma (HCC) chemotherapy. Oxaliplatin (OXA), as one of the first-line chemotherapeutic drugs for HCC, abnormally activates the PI3K/AKT/mTOR signaling pathway and DNA damage repair pathway (NHEJ and HR), causing drug resistance and consequnet compromised efficacy. Herein, we developed a hollow polydopamine nanoparticle (H-PDA)-based nano-delivery system (O/P-HP) that contained OXA and a dual PI3K/mTOR inhibitor PKI-587 with complementary effects for combating drug resistance in cancer chemotherapy. The hollow structure of H-PDA endowed O/P-HP with high loading efficiencies of OXA and PKI-587-up to 49.6% and 7.0%, respectively. In addition, benefiting from the intracellular delivery of H-PDA as well as the highly concentrated drugs therein, O/P-HP inhibited the proliferation of OXA-resistant HR cells, resulting in a cell viability of only 17.63%. These values were significantly superior to those with OXA single-agent treatment and treatment with free OXA in combination with PKI-587. We examined the intrinsic mechanisms of the combination therapy: O/PHP had excellent anti-cancer effects via the simultaneous upstream and downstream action to re-sensitize HR cells to chemotherapy; OXA induced strong apoptosis via the direct platinum lesions on DNA molecules, while PKI-587 normalized the abnormally activated PI3K/AKT/mTOR signaling pathway and DNA damage repair pathway (NHEJ and HR) that could attenuate the effectiveness of OXA, thus resulting in inhibition of cell proliferation, migration and DNA repair enzyme activity and the augment of apoptotic effects. Such combination therapy, with simultaneous upstream and downstream action, may be a strategy for minimizing resistance for anti-cancer treatments.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Preparações Farmacêuticas , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Indóis , Neoplasias Hepáticas/tratamento farmacológico , Morfolinas , Oxaliplatina , Fosfatidilinositol 3-Quinases , Polímeros , Triazinas
17.
Ann Nucl Med ; 35(5): 617-627, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33738763

RESUMO

PURPOSE: To establish and validate a regional lymph node (LN) metastasis prediction model of colorectal cancer (CRC) based on 18F-FDG PET/CT and radiomic features using machine-learning methods. METHODS: A total of 199 colorectal cancer patients underwent pre-therapy diagnostic 18F-FDG PET/CT scans and CRC radical surgery. The Chang-Gung Image Texture Analysis toolbox (CGITA) was used to extract 70 PET radiomic features reflecting 18F-FDG uptake heterogeneity of tumors. The least absolute shrinkage and selection operator (LASSO) algorithm was used to select radiomic features and develop a radiomic signature score (Rad-score). The training set was used to establish five machine-learning prediction models and the test set was used to test the efficacy of the models. The effectiveness of the models was compared by ROC analysis. RESULTS: The CRC patients were divided into a training set (n = 144) and a test set (n = 55). Two radiomic features were selected to build the Rad-score. Five machine-learning algorithms including logistic regression, support vector machine (SVM), random forest, neural network and eXtreme gradient boosting (XGBoost) were used to established models. Among the five machine-learning models, logistic regression (AUC 0.866, 95% CI 0.808-0.925) and XGBoost (AUC 0.903, 95% CI 0.855-0.951) models performed the best. In the training set, the AUC of these two models were significantly higher than that of the LN metastasis status reported by 18F-FDG PET/CT for differentiating positive and negative regional LN metastases in CRC (all p < 0.05). Good efficacy of the above two models was also achieved in the test set. We created a nomogram based on the logistic regression model that visualized the results and provided an easy-to-use method for predicting regional LN metastasis in patients with CRC. CONCLUSION: In this study, five machine-learning models for preoperative prediction of regional LN metastasis of CRC based on 18F-FDG PET/CT and PET-based radiomic features were successfully developed and validated. Among them, the logistic regression and XGBoost models performed the best, with higher efficacy than 18F-FDG PET/CT in both the training and test sets.

18.
Comput Math Methods Med ; 2021: 6633755, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777167

RESUMO

Aim: COVID-19 has caused large death tolls all over the world. Accurate diagnosis is of significant importance for early treatment. Methods: In this study, we proposed a novel PSSPNN model for classification between COVID-19, secondary pulmonary tuberculosis, community-captured pneumonia, and healthy subjects. PSSPNN entails five improvements: we first proposed the n-conv stochastic pooling module. Second, a novel stochastic pooling neural network was proposed. Third, PatchShuffle was introduced as a regularization term. Fourth, an improved multiple-way data augmentation was used. Fifth, Grad-CAM was utilized to interpret our AI model. Results: The 10 runs with random seed on the test set showed our algorithm achieved a microaveraged F1 score of 95.79%. Moreover, our method is better than nine state-of-the-art approaches. Conclusion: This proposed PSSPNN will help assist radiologists to make diagnosis more quickly and accurately on COVID-19 cases.


Assuntos
/diagnóstico por imagem , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Diagnóstico por Computador/métodos , Imageamento Tridimensional/métodos , Redes Neurais de Computação , Pneumonia/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Algoritmos , Infecções Comunitárias Adquiridas/complicações , Bases de Dados Factuais , Humanos , Informática Médica , Pneumonia/complicações , Radiografia Torácica , Reprodutibilidade dos Testes , Estudos Retrospectivos , Software , Processos Estocásticos , Tomografia Computadorizada por Raios X , Tuberculose Pulmonar/complicações
19.
Biochem Biophys Res Commun ; 552: 170-175, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33751934

RESUMO

Biobased production of 5-aminovalerate (5AVA) from biomass can support a sustainable and economic biorefinery process to produce bio-based nylon 5 for food packaging materials. Cost-competitive production of 5AVA from biomass is a key factor in the successful commercialization of nylon 5. Bioproduction of 5AVA is a promising candidate for the industrial process to the current petrochemical route. In this study, we developed an artificial 2-keto-6-aminocaproate-mediated pathway for cost-competitive and high efficiency production of 5AVA in engineered Escherichia coli. Firstly, the combination of native l-lysine α-oxidase (RaiP) from Scomber japonicas, α-ketoacid decarboxylase (KivD) from Lactococcus lactis and aldehyde dehydrogenase (PadA) from Escherichia coli could efficiently convert l-lysine into 5AVA. Moreover, the engineered strains ML03-PnirB-RKP, ML03-PPL-PR-RKP, ML03-PM1-93-RKP induced by anaerobic condition, temperature-induced, constitutive expression instead of expensive isopropyl ß-D-thiogalactoside were constructed, respectively. The use of nirB promoter induced by anaerobic condition not only could attain a higher titer of 5AVA than PL-PR and M1-93 promoters, but omit cost of expensive exogenous inducers. After the replacement of industrial materials, 5AVA titer successfully reached 33.68 g/L in engineered strain ML03-PnirB-RKP via biotransformation. This biotransformation process conduces to the cosmically industrial 5AVA bioproduction.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33684046

RESUMO

In a modern e-commerce recommender system, it is important to understand the relationships among products. Recognizing product relationships--such as complements or substitutes--accurately is an essential task for generating better recommendation results, as well as improving explainability in recommendation. Products and their associated relationships naturally form a product graph, yet existing efforts do not fully exploit the product graph's topological structure. They usually only consider the information from directly connected products. In fact, the connectivity of products a few hops away also contains rich semantics and could be utilized for improved relationship prediction. In this work, we formulate the problem as a multilabel link prediction task and propose a novel graph neural network-based framework, item relationship graph neural network (IRGNN), for discovering multiple complex relationships simultaneously. We incorporate multihop relationships of products by recursively updating node embeddings using the messages from their neighbors. An edge relational network is designed to effectively capture relational information between products. Extensive experiments are conducted on real-world product data, validating the effectiveness of IRGNN, especially on large and sparse product graphs.

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