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1.
Food Funct ; 12(19): 9054-9065, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34608922

RESUMO

The inflammatory and antioxidant effects of a novel Siraitia grosvenorii polysaccharide (SGP-1-1) were investigated in an inflammation-suppressed diabetic nephropathy (DN) mouse model, and the underlying molecular mechanisms of inflammation and oxidative stress in SGP-1-1-treated mouse models were elucidated. The results demonstrated that DN mouse models treated with SGP-1-1 (50, 100, and 200 mg kg-1 d-1) exhibited good inflammation-modulating activity. In addition, histopathological analysis showed that glomerular atrophy, severe glomerular thylakoid hyperplasia, tubular endothelial detachment, basement membrane exposure, cytoplasmic infiltration with inflammatory cells, and interstitial oedema were all alleviated in DN mice after treatment with SGP-1-1. Metabolomics analysis based on UPLC-Q-TOF/MS revealed that a close relationship between the occurrence of DN and the potential 39 biomarkers, especially, leukotriene E3 and arachidonic acid,of which the main invloved metabolic pathways may beglycerophospholipid metabolism, arachidonic acid metabolism and primary bile acid biosynthesis. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis results demonstrated that SGP-1-1 downregulates mRNA and the protein expression of the G protein-coupled cell membrane receptor TLR4 and its downstream protein kinase (NF-κB p65). This, resulted in the inhibition of the TLR4-NF-κB pathway in the peritoneum of DN mice by regulating inflammation, while stimulating the production of superoxide dismutase (SOD) and reducing the production of cytokine (IL-6, TNF-α) and malondialdehyde (MDA).

2.
Opt Lett ; 46(19): 5027-5030, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598261

RESUMO

Waveguide taper, a key component in the photonic integrated circuit (PIC), enables on-chip mode conversion, but large-footprint tapers are detrimental to the PIC, which desires compact and efficient devices. Polarization sensitivity also limits the tapers in the applications involving orthogonal modes. In this work, we design an efficient polarization-insensitive ultra-short MMI-based waveguide taper, through the mode spreading principle and the self-image principle. The proposed taper is 26.3 µm long, one order of magnitude shorter than the standard linear taper. We fabricate the taper, and experimentally demonstrate that it exhibits a high transmission efficiency of ∼70% and a wide 1 dB bandwidth of >54nm, for both TE and TM polarizations.

3.
Food Funct ; 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34505615

RESUMO

This study evaluated the hypoglycemic effect of Auricularia auricula polysaccharides (AAPs) on streptozotocin-induced type 2 diabetes mellitus (T2DM) mice using metabolomic analysis. The results of fasting blood glucose, oral glucose tolerance test, fasting serum insulin level, Homeostatic Model Assessment of Insulin Resistance index, TC, TG, HDL-C, LDL-C, and histopathological observation demonstrated that 200 mg per kg body weight per day AAP led to significant hypoglycemic activities. The metabolic profile of the mice was significantly changed after AAP intervention. 45 differential metabolites were screened as biomarkers for AAP adjuvant treatment, and AAPs' effects on the metabolism of amino acids, unsaturated fatty acids, bile acids, and glycerophospholipids were analyzed. Thus, the current results elucidated the metabolic pathway of AAPs for T2DM alleviation and provided guidance for functional food adjuvant development for T2DM treatment.

4.
J Ethnopharmacol ; 281: 114558, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34438030

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Astragali, the dried root of Astragalus mongholicus Bunge, has long been used in traditional Chinese Medicine to treat diabetes. Astragaloside IV (AS-IV), one of the most active ingredients in the root, has been shown to have anti-diabetes ability; however, its underlying mechanism is still unclear. MATERIALS AND METHODS: In this study, we evaluated the hypoglycemic effect and possible mechanisms of AS-IV in diabetic mice and insulin resistance-HepG2 cells. The components of the intestinal microflora in mice with type 2 diabetes mellitus (T2DM) were determined using high-throughput 16S rRNA gene sequencing. Moreover, the molecular mechanisms of specific members of insulin signaling pathways were analyzed. RESULTS: AS-IV significantly reversed the abnormalities in blood lipids, glucose, insulin resistance, as well as oxidative stress levels in T2DM mice. Histological finding showed that AS-IV could protect the cellular architecture of the liver and pancreas. AS-IV also regulated the abundance and diversity of intestinal flora of T2DM mice in a positive direction and increased butyric acid levels. The active role of AS-IV as an anti-diabetic compound by regulating the AMPK/SIRT1 and PI3K/AKT signaling pathways was revealed using a T2DM model and verified through the intervention of inhibitors using insulin-resistance HepG2 cells. CONCLUSION: Our results suggested that AS-IV may be used as an anti-diabetic drug candidate owing to its effects of regulating gut microbiota and AMPK/SIRT1 and PI3K/AKT signaling pathways.

5.
Plant Dis ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253042

RESUMO

Passion fruit (Passiflora edulis) is an economically important fruit crop in many tropical and subtropical regions worldwide. In recent years, passion fruit was widely cultivated in Guangxi Province. In 2020, a rot disease occurred on immature fruit of passion fruit in several commercial orchards of Nanning, Guangxi, caused about 50% incidence. The first appeared as small, irregular, water-soaked, brown lesions on immature fruit. As the disease progressed, the lesions rapidly enlarged, causing fruit rot. A layer of sparse white mycelia appeared on the lesions at high humidity. The disease first developed in June, its peak periods from August to September. Five diseased fruits were collected from five different orchards. The edges of symptomatic fleshy mesocarp tissue were cut into pieces (5 mm × 5 mm), surface-sterilized in 75% ethanol solution for 60 s, rinsed three times with sterilized distilled water, and plated on potato dextrose agar (PDA). Plates were incubated at 25°C in the dark. After 5 days, similar white colonies with abundant aerial mycelia developed from all plated tissue samples. Five isolates were obtained, and they were identified as Phytophthora nicotianae based on morphological characteristics and DNA analysis. Spherical hyphal swellings were commonly produced. Numerous sporangia were formed in sterile soil extract. Sporangia were ovoid or obpyriform, papillate, and measured 25 to 58 µm (average 41 µm) × 21 to 45 µm (average 29 µm). Chlamydospores were spherical and 19 to 43 µm in diameter (average 30 µm) (Erwin and Ribeiro 1996). The genomic DNA of a representative isolate Seg2-5 was extracted from mycelia through modified CTAB method (Murray and Thompson 1980). The rDNA internal transcribed spacer (ITS) region, ypt1, and coxII were amplified and sequenced with primers ITS1/ITS4 (White et al., 1990), Yph1F/Yph2R (Schena et al. 2008), and FM75F/FM78R (Villa et al. 2006), respectively. BLAST searches of the ITS, ypt1, and coxII sequences (Accession No. MW470847, MW770870, and MW770871) showed 99 to 100% identity with sequences of P. nicotianae (Accession No. JF792540, MK058408, and MH551183). Based on morphological characteristics and phylogenetic analysis, isolate Seg2-5 was identified as P. nicotianae. To confirm pathogenicity, asymptomatic and immature fruits 'Mantianxing' of passion fruit were previously disinfested in 0.5% sodium hypochlorite. Mycelial plugs of isolate Seg2-5 were placed onto the surface of fruits by nonwounded and pin-prick inoculation. Blank plugs were used as negative controls. Each treatment had five replicates and the test was repeated twice. Fruits were maintained in plastic boxes at 28°C and the initial disease spots appeared at 3 dpi or 5 dpi with wounded or non-wounded inoculation. After 7 to 10 days, all inoculated fruits showed similar symptoms as observed initially in the field, whereas control fruits remained healthy. P. nicotianae was successfully reisolated and identified from the inoculated fruits based on morphological characters and ITS sequence, thus confirming Koch's postulates. P. nicotianae had been previously isolated from passion fruit in South Africa (Van and Huller 1970), Vietnam (Nguyen et al. 2015), and Fujian Province of China (Luo et al. 1993). To our knowledge, this is the first report of P. nicotianae infecting passion fruit in Guangxi Province, China.

6.
J Med Microbiol ; 70(6)2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34170219

RESUMO

Introduction. Members of the genus Citrobacter are facultative anaerobic Gram-negative bacilli belonging to the Enterobacterales [Janda J Clin Microbiol 1994; 32(8):1850-1854; Arens Clin Microbiol Infect 1997;3(1):53-57]. Formerly, Citrobacter species were occasionally reported as nosocomial pathogens with low virulence [Pepperell Antimicrob Agents Chemother 2002;46(11):3555-60]. Now, they are consistently reported to cause nosocomial infections of the urinary tract, respiratory tract, bone, peritoneum, endocardium, meninges, intestines, bloodstream and central nervous system. Among Citrobacter species, the most common isolates are C. koseri and C. freundii, while C. amalonaticus has seldom been isolated [Janda J Clin Microbiol 1994; 32(8):1850-1854; Marak Infect Dis (Lond) 2017;49(7):532-9]. Further, Citrobacter spp. are usually susceptible to carbapenems, aminoglycosides, tetracyclines and colistin [Marak Infect Dis (Lond) 2017;49(7):532-9].Hypothesis/Gap Statement. As C. amalonaticus is rare, only one clinical isolate, coharbouring carbapenem resistance gene bla IMP-4 and quinolone resistance gene qnrs1, has been reported.Aim. To characterize a carbapenem-resistant C. amalonaticus strain from PR China coharbouring bla IMP-4 and qnrs1.Methodology. Three hundred and forty nonrepetitive carbapenem-resistant Enterobacterales (CRE) strains were collected during 2011-2018. A carbapenem-resistant C. amalonaticus strain was detected and confirmed using a VITEK mass spectrometry-based microbial identification system and 16S rRNA sequencing. Minimum inhibitory concentrations (MICs) for clinical antimicrobials were obtained by the broth microdilution method. Whole-genome sequencing (WGS) was performed for antibiotic resistance gene analysis, and a phylogenetic tree of C. amalonaticus strains was constructed using the Bacterial Pan Genome Analysis (BPGA) tool. The transferability of the resistance plasmid was verified by conjugal transfer.Results. A rare carbapenem-resistant C. amalonaticus strain (CA71) was recovered from a patient with cerebral obstruction and the sequences of 16S rRNA gene shared more than 99 % similarity with C. amalonaticus CITRO86, FDAARGOS 165. CA71 is resistant to ß-lactam, quinolone and aminoglycoside antibiotics, and even imipenem and meropenem (MICs of 2 and 4 mg l-1 respectively), and is only sensitive to polymyxin B and tigecycline. Six antibiotic resistance genes were detected via WGS, including the ß-lactam genes bla IMP-4, bla CTX-M-18 and bla Sed1, the quinolone gene qnrs1, and the aminoglycoside genes AAC(3)-VIIIa, AadA24. Interestingly, bla IMP-4 and qnrs1 coexist on an IncN1-type plasmid (pCA71-IMP) and successfully transferred to Escherichia coli J53 via conjugal transfer. Phylogenetic analysis showed that CA71 is most similar to C. amalonaticus strain CJ25 and belongs to the same evolutionary cluster along with seven other strains.Conclusion. To the best of our knowledge, this is the first report of a carbapenem-resistant C. amalonaticus isolate coharbouring bla IMP-4 and qnrs1.


Assuntos
Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Citrobacter/genética , Resistência a Múltiplos Medicamentos/genética , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/classificação , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Citrobacter/classificação , Citrobacter/efeitos dos fármacos , Citrobacter/isolamento & purificação , Conjugação Genética , DNA Bacteriano/genética , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Genoma Bacteriano/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , RNA Ribossômico 16S/genética , beta-Lactamases/genética
7.
Proc Natl Acad Sci U S A ; 118(25)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34140406

RESUMO

Single-stranded DNA (ssDNA) covered with the heterotrimeric Replication Protein A (RPA) complex is a central intermediate of DNA replication and repair. How RPA is regulated to ensure the fidelity of DNA replication and repair remains poorly understood. Yeast Rtt105 is an RPA-interacting protein required for RPA nuclear import and efficient ssDNA binding. Here, we describe an important role of Rtt105 in high-fidelity DNA replication and recombination and demonstrate that these functions of Rtt105 primarily depend on its regulation of RPA. The deletion of RTT105 causes elevated spontaneous DNA mutations with large duplications or deletions mediated by microhomologies. Rtt105 is recruited to DNA double-stranded break (DSB) ends where it promotes RPA assembly and homologous recombination repair by gene conversion or break-induced replication. In contrast, Rtt105 attenuates DSB repair by the mutagenic single-strand annealing or alternative end joining pathway. Thus, Rtt105-mediated regulation of RPA promotes high-fidelity replication and recombination while suppressing repair by deleterious pathways. Finally, we show that the human RPA-interacting protein hRIP-α, a putative functional homolog of Rtt105, also stimulates RPA assembly on ssDNA, suggesting the conservation of an Rtt105-mediated mechanism.

8.
Adv Sci (Weinh) ; 8(15): e2100753, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34056863

RESUMO

Histone acetylation is a key histone post-translational modification that shapes chromatin structure, dynamics, and function. Bromodomain (BRD) proteins, the readers of acetyl-lysines, are located in the center of the histone acetylation-signaling network. How they regulate DNA repair and genome stability remains poorly understood. Here, a conserved function of the yeast Bromodomain Factor 1 (Bdf1) and its human counterpart TAF1 is reported in promoting DNA double-stranded break repair by homologous recombination (HR). Depletion of either yeast BDF1 or human TAF1, or disruption of their BRDs impairs DNA end resection, Replication Protein A (RPA) and Rad51 loading, and HR repair, causing genome instability and hypersensitivity to DNA damage. Mechanistically, it is shown that Bdf1 preferentially binds the DNA damage-induced histone H4 acetylation (H4Ac) via the BRD motifs, leading to its chromatin recruitment. Meanwhile, Bdf1 physically interacts with RPA, and this interaction facilitates RPA loading in the chromatin context and the subsequent HR repair. Similarly, TAF1 also interacts with H4Ac or RPA. Thus, Bdf1 and TAF1 appear to share a conserved mechanism in linking the HR repair to chromatin acetylation in preserving genome integrity.

9.
Int J Biol Macromol ; 183: 1753-1773, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34048833

RESUMO

The deficiency of chemical-synthesized antiviral drugs when applied in clinical therapy, such as drug resistance, and the lack of effective antiviral drugs to treat some newly emerging virus infections, such as COVID-19, promote the demand of novelty and safety anti-virus drug candidate from natural functional ingredient. Numerous studies have shown that some polysaccharides sourcing from edible and medicinal fungus (EMFs) exert direct or indirect anti-viral capacities. However, the internal connection of fungus type, polysaccharides structural characteristics, action mechanism was still unclear. Herein, our review focus on the two aspects, on the one hand, we discussed the type of anti-viral EMFs and the structural characteristics of polysaccharides to clarify the structure-activity relationship, on the other hand, the directly or indirectly antiviral mechanism of EMFs polysaccharides, including virus function suppression, immune-modulatory activity, anti-inflammatory activity, regulation of population balance of gut microbiota have been concluded to provide a comprehensive theory basis for better clinical utilization of EMFs polysaccharides as anti-viral agents.


Assuntos
Agaricales/química , Anti-Inflamatórios , Antivirais , COVID-19/tratamento farmacológico , Polissacarídeos Fúngicos , Fatores Imunológicos , SARS-CoV-2/imunologia , Anti-Inflamatórios/química , Anti-Inflamatórios/classificação , Anti-Inflamatórios/uso terapêutico , Antivirais/química , Antivirais/classificação , Antivirais/uso terapêutico , COVID-19/imunologia , COVID-19/prevenção & controle , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/classificação , Polissacarídeos Fúngicos/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/classificação , Fatores Imunológicos/uso terapêutico
10.
Acta Cardiol ; : 1-7, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33871328

RESUMO

BACKGROUND: Previous meta-analyses comparing major bleeding of uninterrupted non-vitamin K antagonist oral anticoagulants (NOACs) versus uninterrupted vitamin K antagonist (VKA) during catheter ablation (CA) of atrial fibrillation (AF) had no consensus. This meta-analysis was performed to comprehensively evaluate the risk of major bleeding events of these two anticoagulant strategies. METHODS: We searched online databases for randomised controlled trials that compared major bleeding events of uninterrupted NOACs and VKA during CA of AF. A fixed-effect model was used if P-value was > 0.10 and I2 was < 50%, otherwise a random- effect model was used. RESULTS: Six studies including 2392 patients were included in the analysis. The incidence of major bleeding was lower in the NOACs group than in the VKA group (OR = 0.56, 95% CI = 0.34 - 0.93, I2 = 38%, p = 0.15). Subgroup analyses showed that the incidence of severe puncture site complications was lower in the NOACs group than in the VKA group (OR = 0.53, 95% CI = 0.30 - 0.96, I2 = 16%, p = 0.32). But the incidence of cardiac tamponade (OR = 0.53, 95% CI = 0.23 - 1.26, I2 = 0%, p = 0.46), intracranial (OR = 0.25, 95% CI = 0.03 - 2.23, I2 = 0%, p = 0.82) and gastrointestinal bleeding (OR = 0.98, 95% CI = 0.18 - 5.39, I2 = 0%, p = 0.43) had no statistically differences between the two groups. CONCLUSION: This meta-analysis suggests that compared to uninterrupted VKA, uninterrupted NOACs are superior in major bleeding during CA of AF, but this superiority existed only in the aspect of severe puncture site complications.

11.
J Proteomics ; 241: 104224, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33845180

RESUMO

"Iron prawn" is a condition of severe growth retardation that fishers call. The giant river prawn (Macrobrachium rosenbergii) is a commercially important species contains high protein content and functional nutrients. However, no proteomic information is available for this species. We performed the shotgun 2DLC-MS/MS proteomic analysis of the total protein from "iron prawn". Total 19,758 peptides corresponding to 2613 high-confidence proteins were identified. These proteins range in size from 40 to 70 kDa. KEGG analysis revealed that the largest group consisting total 102 KEGG pathway proteins comparing the "iron prawn" with the normal prawn. Additionally, 7, 11, 1, 6, and 5 commercially important enzymes were found in the eyestalk, liver, muscle, ovary, and testis, respectively. The functions of these differently expressed enzymes include immune system action against pathogens, muscle contraction, digestive system metabolism, cell differentiation, migration, and apoptosis in the severe growth retardation of "iron prawn". Our work provides insight into the understanding of the formation mechanism of "iron prawn".


Assuntos
Palaemonidae , Animais , Feminino , Água Doce , Ferro , Masculino , Proteômica , Espectrometria de Massas em Tandem
12.
Mol Med Rep ; 23(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33786624

RESUMO

The therapeutic effect of sacubitril/valsartan (S/V) on heart failure has been confirmed, while its role in atherosclerosis remains largely unexplored. The present study aimed to investigate the effects of S/V on the expression of metastasis­associated lung adenocarcinoma transcript 1 (MALAT1), inflammation and apoptosis in human umbilical vein endothelial cells (HUVECs) induced by oxidized low­density lipoprotein (ox­LDL) and to elucidate its possible mechanism. Cell Counting Kit­8 assay was used to detect cell viability. Reverse transcription­quantitative PCR was performed to detect the MALAT1 expression. ELISA was performed to detect the levels of IL­1ß, IL­6 and TNF­α. Flow cytometry was conducted to detect the apoptotic rate of cells. A nitric oxide (NO) detection kit was used to determine the concentration of NO. Western blotting analysis was performed to determine the levels of intercellular cell adhesion molecule (ICAM)­1, vascular cell adhesion molecule (VCAM)­1, endothelin­1, caspase­3, Bax, Bcl­2, Toll­like receptor 4 (TLR4), p65 and p­p65. Compared with the ox­LDL group, S/V treatment significantly increased the cell viability, NO concentration and Bcl­2 expression, decreased the levels of IL­1ß, IL­6 and TNF­α and reduced the expressions of MALAT1, ICAM­1, VCAM­1, cleaved­caspase­3, Bax, TLR4 and p­p65. Overall, the findings suggested that S/V could downregulate the expression of MALAT1, inhibit inflammation and apoptosis and improve endothelial function in ox­LDL­induced HUVECs via inactivating the TLR4/NF­κB signaling pathway. Therefore, S/V might be utilized as a promising therapeutic strategy for the prevention and treatment of atherosclerosis.


Assuntos
Aminobutiratos/farmacologia , Anti-Inflamatórios/farmacologia , Apoptose , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , RNA Longo não Codificante/genética , Tetrazóis/farmacologia , Valsartana/farmacologia , Combinação de Medicamentos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lipoproteínas LDL/farmacologia , NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
13.
ISA Trans ; 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33583570

RESUMO

This paper proposes a kernel function selection mechanism a support vector machine(SVM) under sparse representation and its application in bearing fault diagnosis. For a given data sample, a total of 125,150 different types of kernel functions and different parameters to classify and obtain the accuracy, root mean square error (RMSE) and mean square correlation coefficient (MSCC) of each training, these three values into an overcomplete redundant sparse dictionary. The OMP algorithm is used to solve the sparse coding, that are nonzero in the sparse coding are function types and parameters corresponding to these nonzero atoms according to the one-to-one correspondence between the sparse coding and the sparse dictionary. The nonzero atoms in the sparse coding and the kernel function types and parameters into the kernel function fitness table. According to the selection mechanism, we select the type of kernel function that is most suitable for the given data. A SVM is then composed of selected kernel function types, and PSO algorithm is used to the relevant parameters for classification of unknown data to Finally, we perform simulations and engineering experiments involving high-speed bearing fault diagnosis to verify the superiority of the selection mechanism.

14.
Medicine (Baltimore) ; 100(6): e24619, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33578573

RESUMO

ABSTRACT: CD4+T cell epitopes plays a key role in anti-tuberculosis (TB) immunity, CD4+T cell epitopes suitable for the domestic population are lacking. Therefore, we predicted and identified novel CD4+T cell epitopes.The bioinformatics software, namely, DNAStar (DNASTAR of the United States), SYFPEITHI (INTERFACTORS INSTITUT Für ZELL Biologie of Germany), RANKPEP, and NetMHC IIpan (National Cancer Institute, United States of America), were used to comprehensively predict the CD4+T cell immune epitope of Mycobacterium TB, and the predicted epitope polypeptide was synthesized by the standard Fmoc scheme. The proliferation of PBMC and CD4+T cells stimulated by peptides was preliminarily detected by the CCK8 method. Then, the candidate polypeptides screened out by the CCK8 method were verified again by the BrdU assay, and flow cytometry was performed to analyze further the extent of their stimulation on the proliferation of CD4+T cells. The changes in the secreted cytokines IFN-γ, TNF-α, IL-2, and IL-10 before and after the candidate polypeptide stimulation of CD4+T lymphocytes were detected by ELISA. The preliminary humoral immunity test was conducted by indirect ELISA to evaluate the serological diagnostic value of the CD4+T cell epitope polypeptide.In this study, 5 novel candidate CD4+T cell epitope polypeptides with the amino acid sequences of LQGQWRGAAGTAAQA, PVTLAETGSTLLYPL, AAAWGGSGSEAYQGV, QFVYAGAMSGLLDPS, and KAALTRTASNMNAAA and others that have not been reported in the research were predicted. For convenience, the 5 candidates were successively named as P39, P50, P40, P185, and P62. P39, P62, and the mixed peptide P39+P62 could effectively induce the proliferation of CD4+T cells and increase the secretion of IFN-γ, TNF-α, and IL-2 from the CD4+T cells, while reducing the content of IL-10. The serological test showed that the sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) of P39 were 75%, 67.71%, and 0.844, respectively. The sensitivity, specificity, and AUC of P62 were 91.66%, 46.87%, and 0.649, respectively. The sensitivity of the mixed peptide P39+P62 was 95.83%, the specificity was 97.91%, and the AUC was 0.793.The P39 and P62 polypeptides were predicted and identified as potential CD4+T cell immune epitope polypeptides of M. TB. The polypeptide had better diagnosis effect, which provided potential candidate epitope polypeptides for the development of TB-specific diagnosis reagents and novel TB epitope vaccines.


Assuntos
Antígenos de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Mycobacterium tuberculosis/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Sensibilidade e Especificidade
15.
Phys Chem Chem Phys ; 23(8): 4856-4864, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33615322

RESUMO

Nitrogen is one of the most significant non-native interstitial elements that is present in the structure of Fe. Initial stage nitridation dramatically influences the mechanical properties of steel, especially for micro to nanoscale applications, but is not yet fully understood. By means of reactive force field molecular dynamics (ReaxFF MD) simulations, the initial stage of the nitridation process of nanofilm Fe, as well as its role on the mechanical properties of the material, were investigated. To clarify the temperature effect, nitridation was simulated in the range of 500-900 K, demonstrating that the adsorption of both N and H atoms into Fe was enhanced by thermal actuation. Corresponding tension test simulations were performed, manifesting that the Fe nanofilm nitrided at 600 K presents the highest yield stress. Further analysis shows that there is a competitive mechanism between the inward diffusion of N atoms that enhances the strength and simultaneous adsorption of H atoms, which leads to brittleness of the material as the temperature increases. Hence, an intermediate temperature could lead to optimal mechanical properties due to the balance of improving the strength while controlling the brittleness of the material. To probe the deformation mechanism, evolutions of partial dislocation and twin boundary at plasticity beginning for pure Fe and the nitrided Fe nanofilm are discussed. The present results show the nitridation strengthening technology of Fe in NH3 and its related microscale mechanism, which may theoretically support the technical design and improvement in the properties of steel.

16.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33602814

RESUMO

The ubiquitin E3 ligase Bre1-mediated H2B monoubiquitination (H2Bub) is essential for proper DNA replication and repair in eukaryotes. Deficiency in H2Bub causes genome instability and cancer. How the Bre1-H2Bub pathway is evoked in response to DNA replication or repair remains unknown. Here, we identify that the single-stranded DNA (ssDNA) binding factor RPA acts as a key mediator that couples Bre1-mediated H2Bub to DNA replication and repair in yeast. We found that RPA interacts with Bre1 in vitro and in vivo, and this interaction is stimulated by ssDNA. This association ensures the recruitment of Bre1 to replication forks or DNA breaks but does not affect its E3 ligase activity. Disruption of the interaction abolishes the local enrichment of H2Bub, resulting in impaired DNA replication, response to replication stress, and repair by homologous recombination, accompanied by increased genome instability and DNA damage sensitivity. Notably, we found that RNF20, the human homolog of Bre1, interacts with RPA70 in a conserved mode. Thus, RPA functions as a master regulator for the spatial-temporal control of H2Bub chromatin landscape during DNA replication and recombination, extending the versatile roles of RPA in guarding genome stability.


Assuntos
Reparo do DNA , Replicação do DNA , Histonas/metabolismo , Proteína de Replicação A/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , DNA de Cadeia Simples , Histonas/genética , Recombinação Homóloga , Metanossulfonato de Metila/toxicidade , Domínios e Motivos de Interação entre Proteínas/genética , Proteína de Replicação A/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
17.
BMC Psychiatry ; 21(1): 16, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413238

RESUMO

BACKGROUND: A pandemic is a very stressful event, especially for highly vulnerable people (e.g., older adults). The purpose of the current study was to investigate the main and interactive relationships of social support and resilience on individual mental health during the COVID-19 pandemic across three age groups: emerging adults, adults, and older adults. METHODS: A survey was conducted with 23,192 participants aged 18-85. Respondents completed a questionnaire, including items on the COVID-19-related support they perceived from different sources, the abbreviated version of the Connor-Davidson Resilience Scale, and the Mental Health Inventory. RESULTS: Latent profile analysis identified five profiles of social support, and the patterns of potential profiles were similar in all groups. However, category distribution in the five profiles was significantly different among the age groups. Furthermore, analysis using the BCH command showed significant differences in mental health among these profiles. Lastly, interactive analyses indicated resilience had a positive relationship with mental health, and social support served as a buffer against the negative impact of low resilience on mental health. CONCLUSIONS: This study provides quantitative evidence for socioemotional selectivity theory (SST) and enables several practical implications for helping different age groups protecting mental health during pandemic.


Assuntos
COVID-19 , Resiliência Psicológica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Saúde Mental , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Apoio Social , Adulto Jovem
18.
Crit Rev Food Sci Nutr ; 61(10): 1670-1688, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32436397

RESUMO

Background: Although many studies have shown that consumption of probiotics is relevant to diabetes, the effects of probiotics improves clinical outcomes in type 2 diabetes have yielded conflicting results. The aim of this meta-analysis was conducted to assess the effects of probiotics supplementation on glycemic, blood lipids, pressure and inflammatory control in type 2 diabetes.Methods: PubMed, Web of science, Embase and the Cochrane Library databases were searched for relevant studies from February 2015 up to Janurary 2020, with no language restrictions. The pooled results were calculated with the use of a random-effects model to assess the impact of supplemental probiotics on glycemic, blood lipids, pressure and inflammatory control in type 2 diabetes. Additionally, subgroup analysis was conducted based on patients age, body mass index (BMI), country and duration of the probiotics supplement, respectively.Results: 13 studies were included in this meta-analysis, involving a total of 818 participants in 8 countries. Overall, compared with control groups, the subjects who received multiple species of probiotics had a statistically significant reduction in fasting blood sugar (FBS), homeostasis model assessment of insulin resistance (HOMA-IR), total cholesterol (TC), triglycerides (TG), systolic blood pressure (SBP), diastolic blood pressure (DBP) and tumor necrosis factor (TNF) -α [standardized mean difference (SMD): -0.89 mg/Dl, 95% CI: -1.66, -0.12 mg/dL; SMD: -0.43, 95% CI: -0.63, -0.23; SMD: -0.19 mg/dL, 95% CI: -0.36, -0.01 mg/dL; SMD: -0.23 mg/dL, 95% CI: -0.40, -0.05 mg/dL; SMD: -5.61 mmHg, 95% CI: -9.78, -1.45 mmHg; SMD: -3.41 mmHg, 95% CI: -6.12, -0.69 mmHg; and SMD: 6.92 pg/ml, 95% CI: 5.95, 7.89 pg/ml, respectively]. However, the subjects who received single-species of probiotic or probiotic with co-supplements in food only changed FBS, HOMA-IR, DBP and TG levels. Moreover, subgroup analyses revealed that the effects of probiotics supplementation on FBS, HMOA-IR, SBP and DBP are significantly influenced by patients age, body mass index (BMI), country and duration of the probiotics supplement.Conclusion: Our analysis revealed that glycemic, lipids, blood pressure and inflammation indicators are significantly improved by probiotic supplementation, particularly the subjects who ages ≤ 55, baseline BMI< 30 kg/m2, duration of intervention more than 8 weeks, and received multiple species probiotic.


Assuntos
Diabetes Mellitus Tipo 2 , Hipercolesterolemia , Hiperglicemia , Hipertensão , Probióticos , Glicemia , Pré-Escolar , Suplementos Nutricionais , Humanos , Hiperglicemia/prevenção & controle , Lactente
19.
Int Ophthalmol ; 41(3): 835-843, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33184676

RESUMO

PURPOSE: To evaluate the time trend of axial length (AL) and associated factors in 4- and 5-year-old children in Shanghai from 2013 to 2019. METHODS: This was a 7-year observational study of 985 four-year-old and 1059 five-year-old children in Shanghai. AL, horizontal and vertical corneal curvature, spherical equivalent (SE), and body height and weight were measured. Furthermore, a questionnaire was collected, including time outdoors and bad eyesight habits. RESULTS: In 4-year-old children, no significant difference was found in AL (P = 0.526), but significant differences were observed in SE (P = 0.001), horizontal corneal curvature (P = 0.006), vertical corneal curvature (P = 0.004), height (P < 0.001), and weight (P = 0.022) from 2013 to 2019. In 5-year-old children, no significant differences were found in AL (P = 0.304), SE (P = 0.200), or weight (P = 0.292), but significant differences were observed in horizontal corneal curvature (P = 0.040), vertical corneal curvature (P = 0.015), and height (P < 0.001) from 2013 to 2019. Multivariate analyses revealed that AL was mainly significantly associated with boys and time outdoors in the 4- and 5-year-old children. CONCLUSIONS: The AL of 4- and 5-year-old children remained relatively stable in Shanghai from 2013 to 2019. Longitudinal studies are needed to confirm the relationship between AL elongation and environmental risk factors.


Assuntos
Comprimento Axial do Olho , Córnea , Pré-Escolar , China/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Refração Ocular
20.
Food Chem ; 342: 128536, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33189481

RESUMO

Shepherd's purse as a wild vegetable is getting more and more attention on health benefits. Water extract of shepherd's purse (WESP) was prepared and analyzed for the chemical constituents. The mice were fed high-fructose (HF) diet and treated with WESP at 50, 100 and 200 mg/kg·bw for 8 weeks. The HF-fed mice receiving WESP exhibited the inhibitions against abnormal weight gain, hepatic fat accumulation and lipid metabolic by down-regulating FAS and ACC expressions. WESP also significantly alleviated hyperglycemia, oxidative stress, and inflammatory response by regulating of NF-κB pathway. Moreover, WESP dose-dependently increased the acetic, propionic, and butyric acids levels in HF-fed mice. Furthermore, WESP significantly alleviated the HF-induced gut dysbiosis by reducing the ratio of Firmicutes to Bacteroidetes and increasing the abundance of potential beneficial bacteria. Our findings indicate that WESP may be an effective dietary supplement for preventing the liver damage.


Assuntos
Capsella/química , Doença Hepática Induzida por Substâncias e Drogas/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Água/química , Animais , Antioxidantes/química , Capsella/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Dieta Hiperlipídica , Frutose/toxicidade , Glucose/metabolismo , Teste de Tolerância a Glucose , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico
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