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1.
J Hazard Mater ; 421: 126760, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34396970

RESUMO

Large amounts of epidemiological evidence have confirmed the atmospheric particulate matter (PM2.5) exposure was positively correlated with the morbidity and mortality of respiratory diseases. Nevertheless, its pathogenesis remains incompletely understood, probably resulting from the activation of oxidative stress, inflammation, altered genetic and epigenetic modifications in the lung upon PM2.5 exposure. Currently, biomarker investigations have been widely used in epidemiological and toxicological studies, which may help in understanding the biologic mechanisms underlying PM2.5-elicited adverse health outcomes. Here, the emerging biomarkers to indicate PM2.5-respiratory system interactions were summarized, primarily related to oxidative stress (ROS, MDA, GSH, etc.), inflammation (Interleukins, FENO, CC16, etc.), DNA damage (8-OHdG, γH2AX, OGG1) and also epigenetic modulation (DNA methylation, histone modification, microRNAs). The identified biomarkers shed light on PM2.5-elicited inflammation, fibrogenesis and carcinogenesis, thus may favor more precise interventions in public health. It is worth noting that some inconsistent findings may possibly relate to the inter-study differentials in the airborne PM2.5 sample, exposure mode and targeted subjects, as well as methodological issues. Further research, particularly by -omics technique to identify novel, specific biomarkers, is warranted to illuminate the causal relationship between PM2.5 pollution and deleterious lung outcomes.


Assuntos
Poluentes Atmosféricos , MicroRNAs , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Biomarcadores , Humanos , Pulmão , Estresse Oxidativo , Material Particulado/análise , Material Particulado/toxicidade
2.
IEEE Trans Image Process ; 30: 8553-8566, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618673

RESUMO

Pixelwise single object tracking is challenging due to the competition of running speeds and segmentation accuracy. Current state-of-the-art real-time approaches seamlessly connect tracking and segmentation by sharing computation of the backbone network, e.g., SiamMask and D3S fork a light branch from the tracking model to predict segmentation mask. Although efficient, directly reusing features from tracking networks may harm the segmentation accuracy, since background clutter in the backbone feature tends to introduce false positives in segmentation. To mitigate this problem, we propose a unified tracking-retrieval-segmentation framework consisting of an attention retrieval network (ARN) and an iterative feedback network (IFN). Instead of segmenting the target inside the bounding box, the proposed framework performs soft spatial constraints on backbone features to obtain an accurate global segmentation map. Concretely, in ARN, a look-up-table (LUT) is first built by sufficiently using the information of the first frame. By retrieving it, a target-aware attention map is generated to suppress the negative influence of background clutter. To ulteriorly refine the contour of the segmentation, IFN iteratively enhances the features at different resolutions by taking the predicted mask as feedback guidance. Our framework sets a new state of the art on the recent pixelwise tracking benchmark VOT2020 and runs at 40 fps. Notably, the proposed model surpasses SiamMask by 11.7/4.2/5.5 points on VOT2020, DAVIS2016, and DAVIS2017, respectively. Code is available at https://github.com/JudasDie/SOTS.

3.
Endocrinol Diabetes Nutr (Engl Ed) ; 68(5): 329-337, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34556263

RESUMO

Saponins are the main bioactive substances with anti-hyperglycemic activities of Momordica charantia. This study aimed to verify the effects of M. charantia saponins on insulin secretion and explore the potential underlying mechanisms in INS-1 pancreatic ß-cells. We injured INS-1 cells with 33.3mM glucose and then treated them with saponins. Saponins improved cell morphology and viability as demonstrated by inverted microscopy and CCK8 detection and significantly increased insulin secretion in a concentration-dependent manner as shown by ELISA. Thus, we obtained the optimal concentration for the subsequent experiments. Potential mechanisms were explored by immunofluorescence, western blotting, and RT-qPCR techniques. First, saponins increased the mRNA and protein levels of IRS-2 but decreased the serine 731 phosphorylation level of IRS-2. Moreover, saponins increased the phosphorylation of Akt protein and decreased the protein level of FoxO1, which were both reversed by the PI3K inhibitor ly294002. Furthermore, saponins increased the protein level of the downstream molecule and insulin initiating factor PDX-1, which was also reversed by ly294002. Saponins also increased Akt and PDX-1 mRNA and decreased FoxO1 mRNA, which were both reversed by ly294002. Saponins increased glucose-stimulated insulin secretion (GSIS) and intracellular insulin content, which were reversed by ly294002, as determined by ELISA. The immunofluorescence results also confirmed this tendency. In conclusion, our findings improve our understanding of the function of saponins in INS-1 pancreatic ß-cells and suggest that saponins may increase insulin secretion via the PI3K/Akt/FoxO1 signaling pathway.

4.
Science ; 373(6558): 984-991, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34446600

RESUMO

Protein kinase activity must be precisely regulated, but how a cell governs hyperactive kinases remains unclear. In this study, we generated a constitutively active mitogen-activated protein kinase DYF-5 (DYF-5CA) in Caenorhabditis elegans that disrupted sensory cilia. Genetic suppressor screens identified that mutations of ADR-2, an RNA adenosine deaminase, rescued ciliary phenotypes of dyf-5CA We found that dyf-5CA animals abnormally transcribed antisense RNAs that pair with dyf-5CA messenger RNA (mRNA) to form double-stranded RNA, recruiting ADR-2 to edit the region ectopically. RNA editing impaired dyf-5CA mRNA splicing, and the resultant intron retentions blocked DYF-5CA protein translation and activated nonsense-mediated dyf-5CA mRNA decay. The kinase RNA editing requires kinase hyperactivity. The similar RNA editing-dependent feedback regulation restricted the other ciliary kinases NEKL-4/NEK10 and DYF-18/CCRK, which suggests a widespread mechanism that underlies kinase regulation.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/enzimologia , Cílios/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Edição de RNA , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Animais , Caenorhabditis elegans/genética , Núcleo Celular/metabolismo , Cílios/enzimologia , Ativação Enzimática , Fenótipo , Biossíntese de Proteínas , Proteínas Serina-Treonina Quinases/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA , Estabilidade de RNA , RNA Antissenso/genética , RNA Antissenso/metabolismo , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Transcrição Genética
5.
Front Oncol ; 11: 684941, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34268119

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor of the oral cavity, and long non-coding (lnc)RNA of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was recently reported to play a crucial role in OSCC development and progression. However, potential effects of genetic variants of MALAT1 on the development of OSCC are still unclear. Herein, we performed a case-control study in 1350 patients with OSCC and 1199 healthy controls to evaluate the association between functional single-nucleotide polymorphisms (SNPs) of MALAT1 and OSCC susceptibility, as well as its clinicopathologic characteristics. A TaqMan allelic discrimination assay was used to genotype four tagging SNPs, viz., rs3200401 C>T, rs619586 A>G, rs1194338 C>A, and rs7927113 G>A, and results showed that the MALAT1 rs3200401 T allele had a lower risk of OSCC (adjusted odds ratio (AOR): 0.779, 95% confidence interval (CI): 0.632~0.960, p=0.019) and a higher risk of developing moderately (grade II)/poorly (grade III) differentiated OSCC (AOR: 1.508-fold, 95% CI: 1.049~2.169, p=0.027) under a dominant model. According to environmental carcinogen exposure, patients with a betel quid-chewing habit who carried the T allele of rs3200401 more easily developed high-grade (II/III) OSCC (AOR: 1.588, 95% CI: 1.055~2.390, p=0.027), and patients with the same genotype but who did not chew betel quid had a lower risk of developing lymph node metastasis (AOR: 0.437, 95% CI: 0.255~0.749, p=0.003). In addition to rs3200401, the rs619586 AG/GG genotype was associated with increased risks of developing advanced stages (III+IV) and larger tumor sizes (>T2) compared to the AA genotype, especially in the subgroup of betel quid chewers. Furthermore, analyses of clinical datasets revealed that the MALAT1 expression level was upregulated in OSCC compared to normal tissues, especially in the betel quid-chewing population. These results indicated involvement of MALAT1 SNPs rs3200401 and rs619586 in the development of OSCC and support the interaction between MALAT1 gene polymorphisms and the environmental carcinogen as a predisposing factor for OSCC progression.

6.
Int J Mol Sci ; 22(13)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34281255

RESUMO

Midazolam (MDZ) could affect lymphocyte immune functions. However, the influence of MDZ on cell's K+ currents has never been investigated. Thus, in the present study, the effects of MDZ on Jurkat T lymphocytes were studied using the patch-clamp technique. Results showed that MDZ suppressed the amplitude of delayed-rectifier K+ current (IK(DR)) in concentration-, time-, and state-dependent manners. The IC50 for MDZ-mediated reduction of IK(DR) density was 5.87 µM. Increasing MDZ concentration raised the rate of current-density inactivation and its inhibitory action on IK(DR) density was estimated with a dissociation constant of 5.14 µM. In addition, the inactivation curve of IK(DR) associated with MDZ was shifted to a hyperpolarized potential with no change on the slope factor. MDZ-induced inhibition of IK(DR) was not reversed by flumazenil. In addition, the activity of intermediate-conductance Ca2+-activated K+ (IKCa) channels was suppressed by MDZ. Furthermore, inhibition by MDZ on both IK(DR) and IKCa-channel activity appeared to be independent from GABAA receptors and affected immune-regulating cytokine expression in LPS/PMA-treated human T lymphocytes. In conclusion, MDZ suppressed current density of IK(DR) in concentration-, time-, and state-dependent manners in Jurkat T-lymphocytes and affected immune-regulating cytokine expression in LPS/PMA-treated human T lymphocytes.


Assuntos
Canais de Potássio de Retificação Tardia/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Midazolam/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Animais , Citocinas/metabolismo , Canais de Potássio de Retificação Tardia/metabolismo , Relação Dose-Resposta a Droga , Flumazenil/farmacologia , Antagonistas de Receptores de GABA-A/farmacologia , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Células Jurkat , Cinética , Lipopolissacarídeos/farmacologia , Ativação Linfocitária , Microscopia Confocal , Midazolam/administração & dosagem , Técnicas de Patch-Clamp , Fito-Hemaglutininas/farmacologia , Linfócitos T/imunologia
7.
Pharmgenomics Pers Med ; 14: 839-847, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285552

RESUMO

Purpose: We investigated the interactive effect of rs10506151 polymorphism of the Leucine-rich repeat kinase 2 (LRRK2) gene and type 2 diabetes (T2D) on neurodegenerative disease (ND) risk. Materials and Methods: Data of 17, 927 participants in the Taiwan Biobank (TWB) assessed between 2008 and 2015 were linked to healthcare records in the National Health Insurance Research Database (NHIRD). The odd ratios (ORs) and 95% confidence intervals (CIs) for NDs were determined using logistic regression analysis. Results: There were 145 cases with NDs, and 28.28% (n = 41) of these individuals had T2D. Associations of neurodegenerative disorders with LRRK2 rs10506151 variant and T2D were not significant. The corresponding ORs (95% CI) for NDs were 1.06 (0.75-1.49) in CA/AA compared to CC individuals and 0.93 (0.63-1.39) in those with T2D compared to non-diabetic participants. However, we found evidence of a significant interaction between rs10506151 and T2D (p = 0.0073). After stratification by genotypes of rs10506151, the OR for NDs was 0.37 (CI, 0.17-0.82) in CA/AA individuals with T2D and 1.41 (0.88-2.27) in their CC counterparts. When CA/AA individuals with T2D represented the reference group, the OR (95% CI) was 1.74 (0.81-3.73) in CC individuals with no T2D, 2.47 (CI, 1.14-5.38) in CA/AA individuals with no T2D, and 2.34 (CI, 1.07-5.11) in CC individuals with T2D. Conclusion: Our data indicated that the risk of NDs was significantly lower among diabetic individuals with combined CA/AA of the LRRK2 rs10506151 variant in Taiwan.

8.
Adv Sci (Weinh) ; 8(16): e2100868, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34114348

RESUMO

Antimony selenide (Sb2 Se3 ) nanorod arrays along the [001] orientation are known to transfer photogenerated carriers rapidly due to the strongly anisotropic one-dimensional crystal structure. With advanced light-trapping structures, the Sb2 Se3 nanorod array-based solar cells have excellent broad spectral response properties, and higher short-circuit current density than the conventional planar structured thin film solar cells. However, the interface engineering for the Sb2 Se3 nanorod array-based solar cell is more crucial to increase the performance, because it is challenging to coat a compact buffer layer with perfect coverage to form a uniform heterojunction interface due to its large surface area and length-diameter ratio. In this work, an intermeshing In2 S3 nanosheet-CdS composite as the buffer layer, compactly coating on the Sb2 Se3 nanorod surface is constructed. The application of In2 S3 -CdS composite buffers build a gradient conduction band energy configuration in the Sb2 Se3 /buffer heterojunction interface, which reduces the interface recombination and enhances the transfer and collection of photogenerated electrons. The energy-level regulation minimizes the open-circuit voltage deficit at the interfaces of buffer/Sb2 Se3 and buffer/ZnO layers in the Sb2 Se3 solar cells. Consequently, the Sb2 Se3 nanorod array solar cell based on In2 S3 -CdS composite buffers achieves an efficiency of as high as 9.19% with a VOC of 461 mV.

9.
J Pers Med ; 11(6)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070517

RESUMO

Oral squamous cell carcinoma (OSCC) is a multifactorial malignancy, and its high incidence and mortality rate remain a global public health burden. Polymorphisms in the long intergenic noncoding RNA 673 (LINC00673) have been currently connected to the predisposition to various cancer types. The present study attempted to explore the impact of LINC00673 gene polymorphisms on the risk and progression of OSCC. Three LINC00673 single-nucleotide polymorphisms (SNPs), including rs11655237, rs9914618, and rs6501551, were evaluated in 1231 OSCCC cases and 1194 cancer-free controls. We did not observe any significant association of three individual SNPs with the risk of OSCC between the case and control group. However, while assessing the clinicopathological parameters, patients carrying at least one minor allele of rs9914618 (GA and AA; OR, 1.286; 95% CI, 1.008-1.642; p = 0.043) were found to develop lymph node metastasis more often compared to those who are homozygous for the major allele. Further stratification analyses revealed that this genetic correlation with increased risk of lymphatic spread was further fortified in habitual betel quid chewers (OR, 1.534; 95% CI, 1.160-2.028; p = 0.003) or smokers (OR, 1.320; 95% CI, 1.013-1.721; p = 0.040). Moreover, through analyzing the dataset from The Cancer Genome Atlas (TCGA), we found that elevated LINC00673 levels were associated with the development of large tumors in patients with head and neck squamous cell carcinoma and the risk of lymphatic spread in smokers. These data demonstrate a joint effect of LINC00673 rs9914618 with betel nut chewing or smoking on the progression of oral cancer.

10.
J Pers Med ; 11(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072650

RESUMO

MACC1 (Metastasis Associated in Colon Cancer 1) is found to regulate the hepatocyte growth factor (HGF)/Met signal pathway, and plays an important role in tumor proliferation, angiogenesis, and metastasis. However, the relationships between MACC1 SNPs (single nucleotide polymorphisms) and oral cancer are still blurred. In this study, five SNPs (rs3095007, rs1990172, rs4721888, rs975263, and rs3735615) were genotyped in 911 oral cancer patients and 1200 healthy individuals by real-time polymerase chain reaction (PCR), and the associations of oral cancer with the SNP genotypes, environmental risk factors, and clinicopathological characteristics were further analyzed. Our results showed that individuals who had GC genotype or C-allele (GC + CC) in rs4721888 would have a higher risk for oral cancer incidence than GG genotype after adjustment for betel quid chewing, cigarette smoking, and alcohol drinking. Moreover, the 715 oral cancer patients with a betel quid chewing habit, who had C-allele (TC + CC) in rs975263, would have a higher risk for lymph node metastasis. Further analyses of the sequences of rs4721888 revealed that the C-allele of rs4721888 would be a putative exonic splicing enhancer. In conclusion, MACC1 SNP rs4721888 would elevate the susceptibility for oral cancer, and SNP rs975263 would increase the metastasis risk for oral cancer patients with a betel quid chewing habit. Our data suggest that SNP rs4721888 could be a putative genetic marker for oral cancer, and SNP rs975362 may have the potential to be a prognostic marker of metastasis in an oral cancer patient.

11.
Int J Clin Pract ; : e14213, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33819377

RESUMO

Yang, T, Li, W, Kan, Z, Liu, Y, Peng, M, Shi, H, Effect of dipeptidyl peptidase-4 inhibitors on the progression of atherosclerosis in patients with type 2 diabetes mellitus: A meta-analysis of randomised controlled trials. Int J Clin Pract. 2021; 00:e14213. https://onlinelibrary.wiley.com/doi/10.1111/ijcp.14213. The above article from the International Journal of Clinical Practice, published online on 5 April 2021 in Wiley Online Library (wileyonlinelibrary.com), has been retracted at the request of the authors, and by agreement of the journal Editor in Chief, Charles Young, and John Wiley and Sons Ltd. The retraction has been agreed following an author review of the research which led to the removal of some studies which did not meet the inclusion criteria. Following the removal of these studies the overall sample size was too small and the studies still included too heterogenuous for the results and conclusions to be reliable.

12.
Front Cell Dev Biol ; 9: 640388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33842464

RESUMO

Mesenchymal stem cells (MSCs) have been widely used in the fields of tissue engineering and regenerative medicine due to their self-renewal capabilities and multipotential differentiation assurance. However, capitalizing on specific factors to precisely guide MSC behaviors is the cornerstone of biomedical applications. Fortunately, several key biophysical and biochemical cues of biomaterials that can synergistically regulate cell behavior have paved the way for the development of cell-instructive biomaterials that serve as delivery vehicles for promoting MSC application prospects. Therefore, the identification of these cues in guiding MSC behavior, including cell migration, proliferation, and differentiation, may be of particular importance for better clinical performance. This review focuses on providing a comprehensive and systematic understanding of biophysical and biochemical cues, as well as the strategic engineering of these signals in current scaffold designs, and we believe that integrating biophysical and biochemical cues in next-generation biomaterials would potentially help functionally regulate MSCs for diverse applications in regenerative medicine and cell therapy in the future.

13.
Free Radic Biol Med ; 167: 307-320, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33731308

RESUMO

Lung cancer is the leading cause of cancer-related deaths worldwide. Identifying genetic risk factors and understanding their mechanisms will help reduce lung cancer incidence. The p53 apoptosis effect is related to PMP-22 (PERP), a tetraspan membrane protein, and an apoptotic effector protein downstream of p53. Although historically considered a tumor suppressor, PERP is highly expressed in lung cancers. Stable knockdown of PERP expression induces CL1-5 and A549 lung cancer cell death, but transient knockdown has no effect. Interestingly, relative to the PERP-428GG genotype, PERP-428CC was associated with the highest lung cancer risk (OR = 5.38; 95% CI = 2.12-13.65, p < 0.001), followed by the PERP-428CG genotype (OR = 2.34; 95% CI = 1.55-3.55, p < 0.001). Ectopic expression of PERP-428G, but not PERP-428C, protects lung cancer cells against ROS-induced DNA damage. Mechanistically, PERP-428 SNPs differentially regulate p53 protein stability. p53 negatively regulates the expression of the antioxidant enzymes catalase (CAT) and glutathione reductase (GR), thereby modulating redox status. p53 protein stability is higher in PERP-428C-expressing cells than in PERP-428G-expressing cells because MDM2 expression is decreased and p53 Ser20 phosphorylation is enhanced in PERP-428C-expressing cells. The MDM2 mRNA level is decreased in PERP-428C-expressing cells via PTEN-mediated downregulation of the MDM2 constitutive p1 promoter. This study reveals that in individuals with PERP-428CC, CAT/GR expression is decreased via the PTEN/MDM2/p53 pathway. These individuals have an increased lung cancer risk. Preventive antioxidants and avoidance of ROS stressors are recommended to prevent lung cancer or other ROS-related chronic diseases.


Assuntos
Neoplasias Pulmonares , Proteína Supressora de Tumor p53 , Antioxidantes , Apoptose , Genes Supressores de Tumor , Humanos , Neoplasias Pulmonares/genética , Proteínas de Membrana , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética
14.
Medicine (Baltimore) ; 100(3): e23947, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33545971

RESUMO

BACKGROUND: Subclinical hypothyroidism (SCH) can increase the risk of heart failure (HF) clinically. However, thyroxine therapy for patients with HF and SCH has the risk of developing tachyarrhythmias. At present, there is no sufficient evidence-based medical evidence for levothyroxine in the therapy of this situation, and the treatment issue is still controversial. Therefore, our meta-analysis aims to assess the effectiveness and safety of thyroxine therapy for patients with HF and SCH. METHODS: We searched the related randomized controlled trials that have been published in the following 7 electronic databases: PubMed, Cochrane Library, EMBASE, Chongqing VIP, China National Knowledge Infrastructure, Chinese biomedical literature database, and Wan Fang database. The treatment group was treated with routine HF therapy plus thyroxine, while the control group was treated with HF routine therapy. Main outcome measures effective rate and New York Heart Association classification; Secondary outcome measures included: left ventricular ejection fraction, quality of life score, brain natriuretic peptide / N-terminal pro brain natriuretic peptide, 6-minute walk test, and adverse events. After screening studies and extracting data, we will use Cochrane collaborative tools to evaluate the risk of bias to assess the methodological quality of the included randomized controlled trials. We will use STATA 14.0 software for data synthesis and statistical analysis. Both subgroup analysis and sensitivity analysis will be used to detect potential sources of heterogeneity. In addition, we will use sensitivity analysis to test the stability of the outcomes. If possible, we will perform a funnel chart and Eggers test evaluate publication bias. The quality of the evidence will be evaluated through the grades of recommendations assessment, development, and evaluation system. RESULTS: Our findings will be published in peer-reviewed journals. CONCLUSION: This research will provide evidence about the efficacy and safety of thyroxine in the treatment of patients with HF and SCH. Objective to provide evidence-based medicine basis for thyroxine treatment of patients with SCH and HF. REGISTRATION NUMBER: INPLASY2020100062.


Assuntos
Protocolos Clínicos , Insuficiência Cardíaca/tratamento farmacológico , Hipotireoidismo/tratamento farmacológico , Tiroxina/uso terapêutico , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipotireoidismo/fisiopatologia , Metanálise como Assunto , Revisões Sistemáticas como Assunto
15.
Carbohydr Polym ; 256: 117607, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483084

RESUMO

This study emphasized on structural alteration of rice starch-unsaturated fatty acid complexes by adding trans-2-dodecaenoic acid (t12), trans-oleic acid (t18), cis-oleic acid (c18) and linoleic acid (loa) with different concentration under high-pressure homogenization treatment, and further illustrated the underlying mechanism of modulating digestibility. Results showed that the complex primarily presented as V6 or type IIa polymorph; complex index, content of ordered structure and thermal stability appeared to be positively correlated to the concentration of unsaturated fatty acids. t12 was too mobile to form single helix, leading to the formation of loose matrix; t18 fitted better within the cavity of starch than c18, and formed structural domain with higher compactness and thermal stability; Rloa had lower complex index but higher degree of short-range order, and tended to form alternating amorphous and crystalline structure. The digestibility was higher in the order of Rloa, Rt18, Rc18 and Rt12.


Assuntos
Ácidos Graxos Insaturados/química , Ácidos Láuricos/química , Ácido Linoleico/química , Ácido Oleico/química , Oryza/química , Amido/química , Cristalização , Fractais , Ligação de Hidrogênio , Hidrólise , Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Difração de Raios X
16.
Endocrinol Diabetes Nutr (Engl Ed) ; 68(5): 329-337, 2021 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33069631

RESUMO

Saponins are the main bioactive substances with anti-hyperglycemic activities of Momordica charantia. This study aimed to verify the effects of M. charantia saponins on insulin secretion and explore the potential underlying mechanisms in INS-1 pancreatic ß-cells. We injured INS-1 cells with 33.3mM glucose and then treated them with saponins. Saponins improved cell morphology and viability as demonstrated by inverted microscopy and CCK8 detection and significantly increased insulin secretion in a concentration-dependent manner as shown by ELISA. Thus, we obtained the optimal concentration for the subsequent experiments. Potential mechanisms were explored by immunofluorescence, western blotting, and RT-qPCR techniques. First, saponins increased the mRNA and protein levels of IRS-2 but decreased the serine 731 phosphorylation level of IRS-2. Moreover, saponins increased the phosphorylation of Akt protein and decreased the protein level of FoxO1, which were both reversed by the PI3K inhibitor ly294002. Furthermore, saponins increased the protein level of the downstream molecule and insulin initiating factor PDX-1, which was also reversed by ly294002. Saponins also increased Akt and PDX-1 mRNA and decreased FoxO1 mRNA, which were both reversed by ly294002. Saponins increased glucose-stimulated insulin secretion (GSIS) and intracellular insulin content, which were reversed by ly294002, as determined by ELISA. The immunofluorescence results also confirmed this tendency. In conclusion, our findings improve our understanding of the function of saponins in INS-1 pancreatic ß-cells and suggest that saponins may increase insulin secretion via the PI3K/Akt/FoxO1 signaling pathway.

17.
IEEE Trans Neural Netw Learn Syst ; 32(10): 4499-4513, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33136545

RESUMO

Model compression methods have become popular in recent years, which aim to alleviate the heavy load of deep neural networks (DNNs) in real-world applications. However, most of the existing compression methods have two limitations: 1) they usually adopt a cumbersome process, including pretraining, training with a sparsity constraint, pruning/decomposition, and fine-tuning. Moreover, the last three stages are usually iterated multiple times. 2) The models are pretrained under explicit sparsity or low-rank assumptions, which are difficult to guarantee wide appropriateness. In this article, we propose an efficient decomposition and pruning (EDP) scheme via constructing a compressed-aware block that can automatically minimize the rank of the weight matrix and identify the redundant channels. Specifically, we embed the compressed-aware block by decomposing one network layer into two layers: a new weight matrix layer and a coefficient matrix layer. By imposing regularizers on the coefficient matrix, the new weight matrix learns to become a low-rank basis weight, and its corresponding channels become sparse. In this way, the proposed compressed-aware block simultaneously achieves low-rank decomposition and channel pruning by only one single data-driven training stage. Moreover, the network of architecture is further compressed and optimized by a novel Pruning & Merging (PM) module which prunes redundant channels and merges redundant decomposed layers. Experimental results (17 competitors) on different data sets and networks demonstrate that the proposed EDP achieves a high compression ratio with acceptable accuracy degradation and outperforms state-of-the-arts on compression rate, accuracy, inference time, and run-time memory.

18.
J Hazard Mater ; 406: 124626, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33296760

RESUMO

Amorphous silica nanoparticle (SiNPs) has tremendous potential for a host of applications, while its mass production, broad application and environmental release inevitably increase the risk of human exposure. SiNPs could enter into the human body through different routes such as inhalation, ingestion, skin contact and even injection for medical applications. The cardiovascular system is gradually recognized as one of the primary sites for engineered NPs exerting adverse effects. Accumulating epidemiological or experimental evidence support the association between SiNPs exposure and adverse cardiovascular effects. However, this topic is still in its infancy, and the literature shows high inter-study variability and even contradictory results. New challenges still present in the safety evaluation of SiNPs, and its toxicological mechanisms are poorly understood. Here, scientific papers related to cardiovascular studies of SiNPs in vivo and in vitro were selected, and the updated particle-caused cardiovascular toxicity and potential mechanisms were summarized. Moreover, the understanding of how factors primarily including exposure dose, route of administration, particle size and surface properties, influence the interaction between SiNPs and cardiovascular system was discussed. In particular, the adverse outcome pathway (AOP) framework by which SiNPs cause deleterious effects in the cardiovascular system was described, aiming to provide useful information necessary for the regulatory decision and to guide a safer application of nanotechnology.


Assuntos
Sistema Cardiovascular , Nanopartículas , Humanos , Nanopartículas/toxicidade , Nanotecnologia , Tamanho da Partícula , Dióxido de Silício/toxicidade
19.
Mater Sci Eng C Mater Biol Appl ; 118: 111387, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254993

RESUMO

Mechanical aspects of printable hydrogels can impact cell behavior in 3D-bioprinted constructs, and in this context the stiffness of hydrogel-based bioink can serve as an important physical cue in regulating cell differentiation. Here we bioprinted mesenchymal stem cells (MSCs) by the commonly used bioink alginate-gelatin (Alg-Gel) blends and investigated the influence of stiffness on MSC differentiation toward sweat glands. Mechanical properties were assessed through compression testing and it was found that higher compressive modulus was associated with the higher Alg-Gel concentrations. Using these Alg-Gel blends for bioprinting, we demonstrated that stiffness variance cannot cause differences in cell spreading, adhesion and viability. However, MSCs bioprinted by stiffer hydrogels were found to further upregulate the protein and gene expression of sweat gland cell phenotype, function and development of signaling pathways. Furthermore, we found that the increased Yes-associated protein (YAP) localization of nuclei in MSCs when bioprinted by stiffer hydrogels. These results illustrated that the stiffness of Alg-Gel blends is a potent regulator of MSC differentiation, which was possibly achieved through a YAP-dependent mechanotransduction mechanism.


Assuntos
Hidrogéis , Células-Tronco Mesenquimais , Diferenciação Celular , Mecanotransdução Celular , Glândulas Sudoríparas
20.
J Mater Sci Mater Med ; 31(11): 103, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33140191

RESUMO

Alginate-gelatin (Alg-Gel) composite hydrogel is extensively used in extrusion-based bioprinting. Although Alg-Gel blends possess excellent biocompatibility and printability, poor mechanical properties have hindered its further clinical applications. In this study, a series of design by incorporating bioactive glass nanoparticles (BG) (particle size of 12 and 25 nm) into Alg-Gel hydrogel have been considered for optimizing the mechanical and biological properties. The composite Alg-Gel-BG bioink was biophysically characterized by mechanical tests and bioprinting practice. Biocompatibility of Alg-Gel-BG bioink was then investigated by bioprinting mouse dermal fibroblasts. Mechanical tests showed enhanced stiffness with increasing concentration of incorporated BG. But the maximum concentration of BG was determined 1.0 wt% before blends became too viscous to print. Meanwhile, the incorporation of BG did not affect the highly porous structure and biodegradation of Alg-Gel hydrogel, while the mechanical strength and printability were enhanced. In addition, the cellular proliferation and adhesion in the bioprinted constructs were significantly enhanced by BG (12 nm), while extension was not affected. Therefore, our strategy of incorporating BG in Alg-Gel composite hydrogel represents an easy-to-use approach to the mechanical reinforcement of cell-laden bioink, thus demonstrating their suitability for future applications in extrusion-based bioprinting.


Assuntos
Alginatos/química , Bioimpressão , Cerâmica , Fibroblastos/metabolismo , Gelatina/química , Nanopartículas/química , Pele/metabolismo , Engenharia Tecidual/instrumentação , Animais , Materiais Biocompatíveis/química , Biofísica , Adesão Celular , Proliferação de Células , Hidrogéis , Camundongos , Camundongos Endogâmicos C57BL , Porosidade , Impressão Tridimensional , Reologia , Estresse Mecânico , Engenharia Tecidual/métodos , Tecidos Suporte/química , Viscosidade
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