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1.
Opt Express ; 32(12): 20931-20947, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859461

RESUMO

In recent decades, rapid advances in astronomical imaging campaigns have generated an urgent need for detailed spectroscopic surveys with increased speed and efficiency. The 6.5 m MUltiplexed Survey Telescope (MUST) aims to address these current demands. The performance of the multi-object fiber-fed spectrograph (MOFS) plays a critical role for spectroscopic survey telescopes, directly influencing the realization of scientific aims. In this paper, we demonstrate a high-resolution and highly-multiplexed option for MOFS of MUST. The system is believed to be first to apply a 92 mm × 92 mm large-size detector in a Schmidt-like camera and reduces the average central obscuration to 14%. Thanks to the F/1.25 camera design with excellent image quality, the spectrograph achieves up to 800 150µm-large-core optical fibers integration. It can obtain the broadband spectral information (395 nm-435 nm, 520 nm-570 nm, 610 nm-680 nm) of 800 objects with a high resolution of >16,000 within one exposure. The spectrograph theory, design method, and final system scheme of the MOFS can offer good reference and guidance for the spectrograph design in the spectroscopic survey.

2.
Nutr J ; 23(1): 104, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252042

RESUMO

BACKGROUND: The fat-to-muscle mass ratio (FMR), integrating the antagonistic effects of fat and muscle mass, has been suggested as a valuable indicator to assess cardiometabolic health independent of overall adiposity. However, the specific associations of total and regional FMR with cardiometabolic risk are poorly understood. We aimed to examine sex-specific associations of total and regional FMR with single and clustered cardiometabolic risk factors (CRFs). METHODS: 13,505 participants aged 20 years and above were included in the cross-sectional study. Fat mass and muscle mass were assessed using a bioelectrical impedance analysis device. FMR was estimated as fat mass divided by muscle mass in corresponding body parts (whole body, arm, leg, and trunk). Clustered CRFs was defined as the presence of two or more risk factors, including hypertension, elevated blood glucose, dyslipidemia, insulin resistance (IR), and hyperuricemia. IR was assessed by the triglyceride glucose (TyG) index. Multivariable logistic regression models were applied to explore the associations of FMR in the whole body and body parts with single and clustered CRFs. RESULTS: The odds ratios (ORs) increased significantly for all single and clustered CRFs with the per quartile increase of total and regional FMR in both sexes (P for trend < 0.001), following adjustment for confounders. Among the regional parts, FMRs of the legs presented the strongest associations for clustered CRFs in both men and women, with adjusted OR of 8.54 (95% confidence interval (CI): 7.12-10.24) and 4.92 (95% CI: 4.24-5.71), respectively. Significant interactions (P for interaction < 0.05) were identified between age and FMRs across different body parts, as well as between BMI status and FMRs in different regions for clustered CRFs. Restricted cubic splines revealed significant non-linear relationships between FMRs of different body parts and clustered CRFs in both sexes (P for nonlinear < 0.05). CONCLUSIONS: FMRs in the whole body and different regions were significantly associated with single and clustered CRFs in the general Chinese population. The association between FMR and clustered CRFs was more pronounced in youngers than in the elderly.


Assuntos
Fatores de Risco Cardiometabólico , Inquéritos Epidemiológicos , Humanos , Masculino , Feminino , China/epidemiologia , Estudos Transversais , Adulto , Pessoa de Meia-Idade , Inquéritos Epidemiológicos/estatística & dados numéricos , Inquéritos Epidemiológicos/métodos , Fatores Sexuais , Tecido Adiposo , Músculo Esquelético , Adiposidade , Composição Corporal , Adulto Jovem , Fatores de Risco , Idoso , Resistência à Insulina , Doenças Cardiovasculares/epidemiologia
3.
J Environ Manage ; 351: 119844, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103424

RESUMO

Short-term influence of polytetrafluoroethylene micro/nano-plastics (PTFE-MPs/NPs) on the inhibition of copper (Cu2+) and/or ciprofloxacin (CIP) on the nitrifying sludge activities was explored based on concentration addition (CA) and independent action (IA) models. The half maximal inhibitory concentration (IC50) of Cu2+, CIP, PTFE-MPs (3 µm), and PTFE-NPs (800 nm) on the specific ammonium oxidation rate (SAOR) of nitrifying sludge was 64.57, 51.29, 102.33 and 93.33 mg L-1, respectively, while those on the specific nitrite oxidation rate (SNOR) of nitrifying sludge were 77.62, 32.36, 104.70 and 97.72 mg L-1, respectively. Among the five binary mixtures and two ternary mixtures composed by Cu2+, CIP, and/or PTFE-MPs/NPs, it was found that the two joint inhibitory actions from ternary mixtures on the SAOR and SNOR of the sludge showed time-dependent characteristics by analyzing of CA and IA models, while the five combined inhibitory effects from different binary mixtures did not all have time-dependent features. The two joint inhibition actions from diverse ternary mixtures on the SAOR at the exposure time of 60 min and on the SNOR at 90 min showed always concentration-dependent features, while the combined inhibitions with concentration-dependent characteristics had never been observed in the binary Cu2+ and PTFE-NPs mixtures at different exposure time. The Cu2+, CIP, and PTFE-MPs mixtures (or Cu2+, CIP, and PTFE-NPs mixtures) had synergistic actions on the SAOR at 90 min and antagonistic effects on the SNOR at 60 min based on CA and IA models, and these combined inhibitions did not exhibit concentration-dependent characteristics. In contrast, the joint inhibitory effects (on the SAOR and SNOR) with concentration-dependent features were found in the binary mixtures of CIP and PTFE-MPs at different exposure time, and the join inhibition changed from synergism to antagonism as the increasing concentration of mixed CIP and PTFE-MPs. This study provides novel perspectives for understanding the combined influence of plastic particles with different sizes, antibiotics, and heavy metals on the biological wastewater treatment process.


Assuntos
Ciprofloxacina , Cobre , Ciprofloxacina/farmacologia , Esgotos , Microplásticos , Politetrafluoretileno
4.
Biochem Biophys Res Commun ; 649: 101-109, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764112

RESUMO

Candida tropicalis is often reported as the second or third most common pathogen causing fungal infections. Antimicrobial peptides (AMPs) have attracted increasing attention for their broad-spectrum antimicrobial properties and low cytotoxicity. Our previous studies have shown that CGA-N9, a non-membrane-rupturing AMP, crosses the cell membrane to exert anticandidal activity. We speculate that there are some related transporters that assist in the transmembrane transport of CGA-N9. In this study, the relationship between CGA-N9 lethality kinetics and its real-time transmembrane amount in C. tropicalis cells was investigated. The results demonstrated that there was a positive correlation between its candicidal activity and transmembrane amount. A total of 12 oligopeptide transporter (OPT) coding sequences (CDSs) were cloned from C. tropicalis by using the conservative OPT gene sequences of Candida spp. to design primers and were named C. tropicalis OPTs (CtOPTs). The results of RT‒qPCR demonstrated that the expression levels of CtOPT1, CtOPT9 and CtOPT12 were correlated with the CGA-N9 transmembrane amount in a time-dependent manner. The results of molecular docking demonstrated that CtOPT1, CtOPT9 and CtOPT12 interact strongly with CGA-N9. Therefore, CtOPT1, CtOPT9 and CtOPT12 were predicted to assist in the transmembrane transport of the AMP CGA-N9.


Assuntos
Peptídeos Antimicrobianos , Candida tropicalis , Candida tropicalis/genética , Candida tropicalis/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Oligopeptídeos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/metabolismo
5.
J Nanobiotechnology ; 21(1): 427, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968680

RESUMO

Bacterial wound infections are a serious threat due to the emergence of antibiotic resistance. Herein, we report an innovative hybrid nanozyme independent of antibiotics for antimicrobial wound healing. The hybrid nanozymes are fabricated from ultra-small Au NPs via in-situ growth on metal-organic framework (MOF)-stabilised Fe3O4 NPs (Fe3O4@MOF@Au NPs, FMA NPs). The fabricated hybrid nanozymes displayed synergistic peroxidase (POD)-like activities. It showed a remarkable level of hydroxyl radicals (·OH) in the presence of a low dose of H2O2 (0.97 mM). Further, the hybrid FMA nanozymes exhibited excellent biocompatibility and favourable antibacterial effects against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The animal experiments indicated that the hybrid nanozymes promoted wound repair with adequate biosafety. Thus, the well-designed hybrid nanozymes represent a potential strategy for healing bacterial wound infections, without any toxic side effects, suggesting possible applications in antimicrobial therapy.


Assuntos
Infecções Bacterianas , Nanopartículas Metálicas , Estruturas Metalorgânicas , Infecção dos Ferimentos , Animais , Peroxidase , Estruturas Metalorgânicas/farmacologia , Ouro/farmacologia , Peróxido de Hidrogênio/farmacologia , Peroxidases , Cicatrização , Antibacterianos/farmacologia , Bactérias , Catálise
6.
Cell Mol Biol Lett ; 28(1): 93, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993768

RESUMO

BACKGROUND: Periostin is an extracellular matrix protein that plays a critical role in cell fate determination and tissue remodeling, but the underlying role and mechanism of periostin in diabetic cardiomyopathy (DCM) are far from clear. Thus, we aimed to clarify the mechanistic participation of periostin in DCM. METHODS: The expression of periostin was examined in DCM patients, diabetic mice and high glucose (HG)-exposed cardiac fibroblasts (CF). Gain- and loss-of-function experiments assessed the potential role of periostin in DCM pathogenesis. RNA sequencing was used to investigate the underlying mechanisms of periostin in DCM. RESULTS: A mouse cytokine antibody array showed that the protein expression of periostin was most significantly upregulated in diabetic mouse heart, and this increase was also observed in patients with DCM or HG-incubated CF. Periostin-deficient mice were protected from diabetes-induced cardiac dysfunction and myocardial damage, while overexpression of periostin held the opposite effects. Hyperglycemia stimulated the expression of periostin in a TGF-ß/Smad-dependent manner. RNA sequencing results showed that periostin upregulated the expression of nucleosome assembly protein 1-like 2 (NAP1L2) which recruited SIRT3 to deacetylate H3K27ac on the promoters of the branched-chain amino acid (BCAA) catabolism-related enzymes BCAT2 and PP2Cm, resulting in BCAA catabolism impairment. Additionally, CF-derived periostin induced hypertrophy, oxidative injury and inflammation in primary cardiomyocytes. Finally, we identified that glucosyringic acid (GA) specifically targeted and inhibited periostin to ameliorate DCM. CONCLUSION: Overall, manipulating periostin expression may function as a promising strategy in the treatment of DCM.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Sirtuína 3 , Humanos , Camundongos , Animais , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/metabolismo , Sirtuína 3/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Miócitos Cardíacos/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Aminoácidos de Cadeia Ramificada/farmacologia , Fibroblastos/metabolismo
7.
Bioprocess Biosyst Eng ; 46(2): 165-170, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36565343

RESUMO

Endophytic fungi, as a kind of fungi living in the healthy plant tissues and organs, are important sources of natural bioactive products and new microbial resources with high developing value. Therefore, exploration and utilization of endophytic fungi can not only alleviate the problems of resource shortage and ecological balance destruction caused by extracting large number of useful bioactive products from natural plants, but also benefit the protection of rare and endangered plant resources, which is of great significance and economic value. This review mainly expounds the concept of endophytic fungi, analyzes the research advances of endophytic fungi from antioxidant, antibacterial, insecticidal, regulating plant growth, anticancer and antitumor bioactivities and, furthermore, summarizes the existing problems in present research of endophytic fungi and corresponding solutions. We hope that this review could provide references for the development and utilization of endophytic fungi and their bioactive metabolites.


Assuntos
Produtos Biológicos , Endófitos , Endófitos/metabolismo , Fungos/metabolismo , Plantas/microbiologia , Antibacterianos/metabolismo
8.
Angew Chem Int Ed Engl ; 62(45): e202310203, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37786301

RESUMO

Light olefins are abundantly manufactured in the petroleum industry and thus represent ideal starting materials for modern chemical synthesis. Selective and divergent transformations of feedstock light olefins to value-added chemicals are highly sought-after but remain challenging. Herein we report an exceptionally regioselective carbonickelation of light alkenes followed by in situ trapping with three types of nucleophiles, namely a reductant, base, or Grignard reagent. This protocol enables efficient 1,2-hydrofunctionalization, dicarbofunctionalization, and branched-selective Heck-type cross-coupling of light alkenes with aryl and alkenyl reagents to streamline access to diverse alkyl arenes and complex alkenes. Harnessing bulky N-heterocyclic carbene ligands with acenaphthyl backbones for nickel catalysts is crucial to attain high reactivity and selectivity. This strategy provides a rare, modular, and divergent platform for upgrading feedstock alkenes and is expected to find broad applications in medicinal chemistry and industrial processes.

9.
Anal Chem ; 94(8): 3590-3599, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35171578

RESUMO

Monosaccharides play important roles in biological processes. Sensitive and accurate analyses of monosaccharides remain challenging because of their high hydrophilicities and poor ionization efficiencies. Here, we developed a paired derivatization approach with H/D-labeled hydroxylamines for simultaneous quantification of 12 monosaccharides by liquid chromatography tandem mass spectrometry (LC-MS/MS). O-(4-Methoxybenzyl)hydroxylamine hydrochloride (4-MOBHA·HCl) showed higher derivatization efficiency for monosaccharides compared to six other hydroxylamine analogues. The derivatization of monosaccharides was readily achieved in an aqueous solution. Furthermore, the deuterium-labeled isotope reagent, d3-4-MOBHA·HCl, was newly synthesized to stably label monosaccharides to improve its accuracy and precision in complex matrix analysis. As a result, 12 monosaccharides were rapidly detected by LC-MS/MS within 16 min with significant improvements in chromatographic separation and retention time. The detection sensitivity increased by 83 to 1600-fold with limits of quantitation ranging from 0.25 to 3.00 fmol. With the paired derivatization strategy, the monosaccharides could be accurately quantified with good linearity (R2 > 0.99) and satisfactory accuracy (recoveries: 85-110%). Using this method, we achieved sensitive and accurate quantification of the monosaccharide composition of herbal polysaccharides and the change in monosaccharide levels in human cell lines under physiopathological conditions. More importantly, the developed method was able to differentiate between the levels of the monosaccharides in fecal samples of human ulcerative colitis (UC) patients and UC mice compared to their respective controls. The differential monosaccharides determined in human feces provided a good diagnostic performance in distinguishing the UC patients from healthy individuals, showing potential for clinical application.


Assuntos
Monossacarídeos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Humanos , Hidroxilamina , Hidroxilaminas , Indicadores e Reagentes , Camundongos , Monossacarídeos/análise , Espectrometria de Massas em Tandem/métodos
10.
J Cardiovasc Pharmacol ; 79(4): 479-488, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34935702

RESUMO

ABSTRACT: Acute myocardial infarction (AMI) has become the most common cause of death in the developed countries. However, its pathogenesis is poorly understood. Increasing studies have revealed that lncRNAs are important modulators of AMI development. This study aimed to explore the function of lncRNA noncoding repressor of nuclear factor of activated T cells (NRON) in hypoxia/reoxygenation (H/R)-stimulated H9c2 cells. NRON expression in peripheral blood of AMI patients and H/R-stimulated H9c2 cells was measured by quantitative real-time polymerase chain reaction. H9c2 cells were transfected with si-NRON or cotransfected with si-NRON and si-hypoxia-inducible factor-1 alpha (HIF-1α). The viability and apoptosis of these cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay and flow cytometer, respectively. In addition, HIF-1α, AKT/mTOR signal pathways and ERK1/2 were detected by western blot. NRON knockdown in the myocardial infarction mouse model was conducted through adeno-associated virus injection, and cardiac function was evaluated by motion-mode echocardiography. The results showed that NRON was highly expressed in peripheral blood of AMI patients and H/R-stimulated H9c2 cells. NRON knockdown promoted cell viability and inhibited cell apoptosis of H/R-stimulated H9c2 cells. Meanwhile, NRON knockdown also significantly attenuated heart damage and improved cardiac function in an AMI mouse model. Furthermore, compared with si-normal control, NRON knockdown increased the levels of HIF-1α, p-AKT, p-mTOR, and p-ERK1/2. HIF-1α knockdown reversed the effects of NRON knockdown in H/R-stimulated-H9c2 cells damage. Overall, our study revealed that NRON knockdown alleviated H/R-induced cardiomyocyte apoptosis by upregulating HIF-1α expression, suggesting that NRON might be a novel therapeutic target for AMI.


Assuntos
Infarto do Miocárdio , RNA Longo não Codificante , Animais , Apoptose/genética , Hipóxia Celular , Humanos , Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linfócitos T/metabolismo , Serina-Treonina Quinases TOR/metabolismo
11.
Int J Mol Sci ; 23(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36233153

RESUMO

Immobilized enzymes are a significant technological approach to retain enzyme activity and reduce enzyme catalytic cost. In this work, trypsin-incorporated Zn3(PO4)2 hybrid nanoflowers were prepared via mild precipitation and coordination reactions. The controllable preparation of hybrid nanoflowers was achieved by systematically investigating the effects of the raw-material ratio, material concentration and reaction temperature on product morphology and physicochemical properties. The enzyme content of hybrid nanoflowers was about 6.5%, and the maximum specific surface area reached 68.35 m2/g. The hybrid nanoflowers exhibit excellent catalytic activity and environmental tolerance compared to free trypsin, which was attributed to the orderly accumulation of nanosheets and proper anchoring formation. Further, the enzyme activity retention rate was still higher than 80% after 12 repeated uses. Therefore, trypsin/Zn3(PO4)2 hybrid nanoflowers-which combine functionalities of excellent heat resistance, storage stability and reusability-exhibit potential industrial application prospects.


Assuntos
Enzimas Imobilizadas , Nanoestruturas , Biocatálise , Enzimas Imobilizadas/química , Nanoestruturas/química , Tripsina , Zinco
12.
Rev Cardiovasc Med ; 22(4): 1361-1381, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34957777

RESUMO

Due to their high prevalence and incidence, diabetes and atherosclerosis are increasingly becoming global public health concerns. Atherosclerosis is one of the leading causes of morbidity and disability in type 1 and/or type 2 diabetes patients. Atherosclerosis risk in diabetic patients is obviously higher than that of non-diabetic individuals. Diabetes-related glycolipid metabolism disorder has been shown to play a central role in atherosclerosis development and progression. Hyperglycemia and dyslipidemia increase the risks for atherosclerosis and plaque necrosis through multiple signaling pathways, such as a prolonged increase in reactive oxygen species (ROS) and inflammatory factors in cardiovascular cells. Notwithstanding the great advances in the understanding of the pathologies of diabetes-accelerated atherosclerosis, the current medical treatments for diabetic atherosclerosis hold undesirable side effects. Therefore, there is an urgent demand to identify novel therapeutic targets or alternative strategies to prevent or treat diabetic atherosclerosis. Burgeoning evidence suggests that plant and herbal medicines are closely linked with healthy benefits for diabetic complications, including diabetic atherosclerosis. In this review, we will overview the utilization of plant and herbal medicines for the treatment of diabetes-accelerated atherosclerosis. Furthermore, the underlying mechanisms of the ethnopharmacological therapeutic potentials against diabetic atherosclerosis are gathered and reviewed. It is foreseeable that the natural constituents from medicinal plants might be a new hope for the treatment of diabetes-accelerated atherosclerosis.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Dislipidemias , Plantas Medicinais , Aterosclerose/tratamento farmacológico , Aterosclerose/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dislipidemias/diagnóstico , Dislipidemias/tratamento farmacológico , Dislipidemias/epidemiologia , Humanos
13.
J Pept Sci ; 27(9): e3337, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33987904

RESUMO

Antimicrobial peptide L163 was computationally designed by our laboratory; L163 is active against multidrug-resistant (MDR) bacteria but is easily degraded in the plasma and by trypsin. Amino acid substitution, cyclization, and amino-terminal (N-terminal) acetylation were performed to obtain L163 analogs with high stability in the plasma and in trypsin solutions. The stability, antimicrobial activity, and biosafety of L163 and its analogs were investigated. Comparison with unmodified L163 indicated that N-terminal acetylation enhanced the stability against pH, plasma, and trypsin degradation, and phenylalanine (Phe) substitution for leucine (Leu) and cysteine bridge (S-S) cyclization decreased the stability. N-terminal acetylation also enhanced antimicrobial activity against MDR Streptococcus Sc181, Listeria monocytogenes, and Enterococcus E1478F; did not change the activity against MDR Staphylococcus aureus 9, Staphylococcus sciuri P254, and Staphylococcus aureus RN4220; and decreased the activity against Candida tropicalis, Candida albicans, and Enterococcus faecalis Fbc35. Phe substitution for Leu and S-S cyclization decreased the antimicrobial activity. The negative effect of these modifications was detected against biofilm formation by the tested microbial strains. Comparison of Phe substitution for Leu and S-S cyclization indicated that N-terminally acetylated L163 (L163-Ac) is the best candidate. L163-Ac peptide had the highest antibacterial activity and enhanced tolerance to temperature, pH, plasma, and trypsin and low toxicity.


Assuntos
Peptídeos Antimicrobianos , Peptídeo Hidrolases , Acetilação , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Staphylococcus aureus
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(1): 10-20, 2021 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-33899423

RESUMO

Heart sound is one of the common medical signals for diagnosing cardiovascular diseases. This paper studies the binary classification between normal or abnormal heart sounds, and proposes a heart sound classification algorithm based on the joint decision of extreme gradient boosting (XGBoost) and deep neural network, achieving a further improvement in feature extraction and model accuracy. First, the preprocessed heart sound recordings are segmented into four status, and five categories of features are extracted from the signals based on segmentation. The first four categories of features are sieved through recursive feature elimination, which is used as the input of the XGBoost classifier. The last category is the Mel-frequency cepstral coefficient (MFCC), which is used as the input of long short-term memory network (LSTM). Considering the imbalance of the data set, these two classifiers are both improved with weights. Finally, the heterogeneous integrated decision method is adopted to obtain the prediction. The algorithm was applied to the open heart sound database of the PhysioNet Computing in Cardiology(CINC) Challenge in 2016 on the PhysioNet website, to test the sensitivity, specificity, modified accuracy and F score. The results were 93%, 89.4%, 91.2% and 91.3% respectively. Compared with the results of machine learning, convolutional neural networks (CNN) and other methods used by other researchers, the accuracy and sensibility have been obviously improved, which proves that the method in this paper could effectively improve the accuracy of heart sound signal classification, and has great potential in the clinical auxiliary diagnosis application of some cardiovascular diseases.


Assuntos
Ruídos Cardíacos , Algoritmos , Bases de Dados Factuais , Redes Neurais de Computação
15.
Angew Chem Int Ed Engl ; 60(29): 16077-16084, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33901337

RESUMO

The transition-metal-catalyzed C-N cross-coupling has revolutionized the construction of amines. Despite the innovations of multiple generations of ligands to modulate the reactivity of the metal center, ligands for the low-temperature enantioselective amination of aryl halides remain a coveted target of catalyst engineering. Designs that promote one elementary reaction often create bottlenecks at other steps. We here report an unprecedented low-temperature (as low as -50 °C), enantioselective Ni-catalyzed C-N cross-coupling of aryl chlorides with sterically hindered secondary amines via a kinetic resolution process (s factor up to >300). A bulky yet flexible chiral N-heterocyclic carbene (NHC) ligand is leveraged to drive both oxidative addition and reductive elimination with low barriers and control the enantioselectivity. Computational studies indicate that the rotations of multiple σ-bonds on the C2 -symmetric chiral ligand adapt to the changing needs of catalytic processes. We expect this design would be widely applicable to diverse transition states to achieve other challenging metal-catalyzed asymmetric cross-coupling reactions.

16.
Arch Biochem Biophys ; 684: 108334, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32173334

RESUMO

Emerging evidence shows that histone modification and its related regulators are involved in the progression and chemoresistance of ovarian cancer (OC) cells. Our present study found that the expression of Jumonji C domain-containing 2A (JMJD2A), while not JMJD2B or JMJD2C, is increased in OC cells and tissues as compared with that in their corresponding controls. Knockdown of JMJD2A can decrease proliferation while increase cisplatin (CDDP) sensitivity of OC cells. By screening the expression of cytokines involved in the progression of ovarian cancer, we found that knockdown of JMJD2A can inhibit the expression of interleukin-6 (IL-6) and IL-8 in ovarian cancer cells. Recombinant IL-6 (rIL-6) and rIL-8 can attenuate si-JMJD2A-suppressed malignancy of OC cells. Mechanistically, JMJD2A can directly bind with the promoter of IL-6 to trigger its transcription. For IL-8, JMJD2A can increase it mRNA stability in OC cells. Collectively, we revealed that JMJD2A can trigger the malignancy of OC cells via upregulation of IL-6 and IL-8. It suggested that JMJD2A might be a potential target for OC treatment and therapy.


Assuntos
Interleucina-6/metabolismo , Interleucina-8/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Ovarianas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Interleucina-6/genética , Interleucina-8/genética , Histona Desmetilases com o Domínio Jumonji/genética , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/fisiologia , Regulação para Cima
17.
Virol J ; 17(1): 40, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188476

RESUMO

BACKGROUND: The present study aims to explore the functions of circular RNA hsa_circ_0004812 in chronic hepatitis B (CHB) and its underlying molecular mechanisms. METHODS: The expression of circular RNA (circRNA)_0004812 was examined using qRT-PCR and Western blot in blood and liver tissues from CHB patients and healthy volunteers. In the in vitro study, the expression levels of circular RNA hsa_circ_0004812, miR-1287-5p, interferon (IFN)-α, IFN-ß were determined using qRT-PCR and Western blotting in HBV-infected hepatoma cells, respectively. Luciferase and biotin pull-down assays were used to investigate the interactions between miR-1287-5p and circ_0004812. RESULTS: Levels of circ_0004812 were upregulated in CHB patients and HBV-infected hepatoma cells. Knockdown of circ_0004812 increased the expression of IFN-α and IFN-ß in HBV-infected Huh7 cells. MiR-1287-5p was identified as a target of circ_0004812 whose overexpression inhibited the expression of miR-1287-5p. Additionally, circ_0004812 promoted the expression of Follistatin-related protein (FSTL) 1 through inhibiting miR-1287-5p. Circ_0004812/miR-1287-5p/FSTL1 axis regulated HBV-induced immune suppression. CONCLUSION: Circ_0004812 was identified as a potential target for CHB infection. Circ_0004812 promoted the expression of FSTL1 by inhibiting miR-1287-5p.


Assuntos
Proteínas Relacionadas à Folistatina/genética , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Interferons/imunologia , MicroRNAs/genética , RNA Circular/imunologia , Linhagem Celular Tumoral , Proteínas Relacionadas à Folistatina/imunologia , Regulação da Expressão Gênica , Células Hep G2 , Humanos , MicroRNAs/imunologia , RNA Circular/genética , Regulação para Cima
18.
Biochem J ; 476(20): 3069-3080, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31652303

RESUMO

CGA-N9, a peptide derived from human chromogranin A (CGA), was found to have antimicrobial activity in our previous investigation, but its mechanism of action remains unclear. Herein, the mechanism of action of CGA-N9 was investigated. We found that CGA-N9 induced the depolarization of the cell membrane and uptake of calcium ions into the cytosol and mitochondria. With the disruption of the mitochondrial membrane potential, the generation of intracellular reactive oxygen species (ROS) increased. Accordingly, we assessed apoptotic processes in Candida tropicalis cells post-treatment with CGA-N9 and found cytochrome c leakage, chromatin condensation and DNA degradation. The interaction of CGA-N9 with DNA in vitro showed that CGA-N9 did not degrade DNA but bound to DNA via an electrostatic interaction. In conclusion, CGA-N9 exhibits antifungal activity by inducing apoptosis in C. tropicalis.


Assuntos
Antifúngicos/farmacologia , Apoptose/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/metabolismo , Cromogranina A/química , Fragmentos de Peptídeos/farmacologia , Antifúngicos/metabolismo , Cálcio/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cromatina/metabolismo , Cromogranina A/metabolismo , Cromogranina A/farmacologia , Citocromos c/metabolismo , Citosol/metabolismo , Fragmentação do DNA/efeitos dos fármacos , DNA Fúngico/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Fragmentos de Peptídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Eletricidade Estática
19.
Prep Biochem Biotechnol ; 50(9): 954-960, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32532165

RESUMO

As a by-product during flour production, wheat bran is mainly used as raw material for fodder or fermentation. In the present work, wheat bran was extruded with different moisture conditions and the consequently chemical component, absorption capacity, and antioxidant activity of treated wheat bran were analyzed. Results showed that extrusion decreased the particle size and crystallinity of wheat bran, but increased the soluble dietary fiber content of which from 3.08% to 11.78%. Meanwhile, water holding capacity, oil holding capacity for peanut oil and lard, and swelling capacity of WB-W-G-Na reached 5.67 g/g, 3.34 g/g, 3.58 g/g and 4.3 mL/g, respectively. Moreover, DPPH radical scavenging activity of WB-W-G-Na increased from 6.8% to 18.4% and hydroxyl radical scavenging activity increased from 5.3% to 15.9%. Overall, this work provides an excellent pretreatment method for increasing the functional activities of wheat bran in the food industry.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Fibras na Dieta/farmacologia , Manipulação de Alimentos , Indústria Alimentícia , Radical Hidroxila/química , Picratos/química , Água/química
20.
Macromol Rapid Commun ; 40(17): e1900135, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31066491

RESUMO

In this study, a new strategy to synthesize random and alternating multiblock copolymers (MBCs) by the polycondensation of macromonomers' terminal hydroxyl groups with [CpRu(CH3 CN)3 ]PF6 /quinaldic acid as the catalyst is reported, which is often used for the preparation of a variety of biological small molecules via the reaction of allyl ethers. The degrees of hydroxyl functionality (Fn ) of the MBCs are assessed by titration, and the presence of hydroxyl on both the ends of MBCs is also confirmed by a chain-extension experiment of the ring-opening polymerization of D,L-lactide.


Assuntos
Complexos de Coordenação/química , Polímeros/síntese química , Quinolinas/química , Catálise , Estrutura Molecular , Polimerização , Polímeros/química
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