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1.
Small ; 20(7): e2306820, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37802970

RESUMO

Constructing heterojunction of supramolecular arrays self-assembled on metal-organic frameworks (MOFs) with elaborate charge transfer mechanisms is a promising strategy for the photocatalytic oxidation of organic pollutants. Herein, H12 SubPcB-Br (SubPc-Br) and UiO-66 are used to obtain the step-scheme (S-scheme) heterojunction SubPc-Br/UiO-66 for the first time, which is then applied in the photocatalytic oxidation of minocycline. Atomic-level B-O-Zr charge-transfer channels and van der Waals force connections synergistically accelerated the charge transfer at the interface of the SubPc-Br/UiO-66 heterojunction, while the establishment of the B-O-Zr bonds also led to the directional transfer of charge from SubPc-Br to UiO-66. The synergy is the key to improving the photocatalytic activity and stability of SubPc-Br/UiO-66, which is also verified by various characterization methods and theoretical calculations. The minocycline degradation efficiency of supramolecular SubPc-Br/UiO-66 arrays reach 90.9% within 30 min under visible light irradiation. The molecular dynamics simulations indicate that B-O-Zr bonds and van der Waals force contribute significantly to the stability of the SubPc-Br/UiO-66 heterojunction. This work reveals an approach for the rational design of semiconducting MOF-based heterojunctions with improved properties.

2.
Opt Lett ; 49(3): 578-581, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300063

RESUMO

An approach to obtain a yellow laser is demonstrated for the first time to our knowledge by the employment of an Nd3+-doped YVO4 crystal and a LBO frequency-doubling crystal. Differing from the previous stimulated self-Raman radiation of Nd:YVO4, a direct 1176 nm lasing, without a high-intensity intracavity 1064 nm laser, was realized by utilizing an electron-phonon coupling effect and amplifying the thermally activated vibronic transitions. Combining with intracavity frequency-doubling, a yellow laser at 588 nm was obtained. At the pump power of 14.3 W, the output power of the yellow laser was 1.17 W, corresponding to a diode-to-visible efficiency of 8.2%. Moreover, for the first time, the yellow laser at 584 nm with output power of 164 mW was realized by tuning the filter, indicating the great potential of such an electron-phonon coupling laser for a wavelength extension in the yellow regime.

3.
Physiol Plant ; 176(2): e14296, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650503

RESUMO

In Dunaliella tertiolecta, a microalga renowned for its extraordinary tolerance to high salinity levels up to 4.5 M NaCl, the mechanisms underlying its stress response have largely remained a mystery. In a groundbreaking discovery, this study identifies a choline dehydrogenase enzyme, termed DtCHDH, capable of converting choline to betaine aldehyde. Remarkably, this is the first identification of such an enzyme not just in D. tertiolecta but across the entire Chlorophyta. A 3D model of DtCHDH was constructed, and molecular docking with choline was performed, revealing a potential binding site for the substrate. The enzyme was heterologously expressed in E. coli Rosetta (DE3) and subsequently purified, achieving enzyme activity of 672.2 U/mg. To elucidate the role of DtCHDH in the salt tolerance of D. tertiolecta, RNAi was employed to knock down DtCHDH gene expression. The results indicated that the Ri-12 strain exhibited compromised growth under both high and low salt conditions, along with consistent levels of DtCHDH gene expression and betaine content. Additionally, fatty acid analysis indicated that DtCHDH might also be a FAPs enzyme, catalyzing reactions with decarboxylase activity. This study not only illuminates the role of choline metabolism in D. tertiolecta's adaptation to high salinity but also identifies a novel target for enhancing the NaCl tolerance of microalgae in biotechnological applications.


Assuntos
Betaína , Colina Desidrogenase , Tolerância ao Sal , Betaína/metabolismo , Tolerância ao Sal/genética , Colina Desidrogenase/metabolismo , Colina Desidrogenase/genética , Colina/metabolismo , Clorofíceas/genética , Clorofíceas/fisiologia , Clorofíceas/enzimologia , Clorofíceas/metabolismo , Microalgas/genética , Microalgas/enzimologia , Microalgas/metabolismo , Simulação de Acoplamento Molecular , Cloreto de Sódio/farmacologia
4.
Phys Chem Chem Phys ; 26(5): 3974-3980, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38221866

RESUMO

On the basis of variable-temperature single-crystal X-ray diffraction, variable-temperature/frequency dielectric analysis, variable-temperature solid-state nuclear magnetic resonance spectroscopy, and molecular dynamics simulations, here we present a new model of crystalline supramolecular rotor (i-PrNHMe2)[CdBr3], where a conformationally flexible near-spherical (i-PrNHMe2)+ cation functions as a rotator and a rod-like anionic coordination polymer {[CdBr3]-}∞ acts as the stator, and the adhesion of them is realized by charge-assisted hydrogen bonds.

5.
J Cell Physiol ; 238(6): 1324-1335, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37087727

RESUMO

MADS transcription factors are involved in the regulation of fruit development and carotenoid metabolism in plants. However, whether and how carotenoid accumulation is regulated by algal MADS are largely unknown. In this study, we first used functional complementation to confirm the functional activity of phytoene synthase from the lutein-rich Dunaliella sp. FACHB-847 (DbPSY), the key rate-limiting enzyme in the carotenoid biosynthesis. Promoters of DbPSY and DbLcyB (lycopene ß-cyclase) possessed multiple cis-acting elements such as light-, UV-B-, dehydration-, anaerobic-, and salt-responsive elements, W-box, and C-A-rich-G-box (MADS-box). Meanwhile, we isolated one nucleus-localized MADS transcription factor (DbMADS), belonging to type I MADS gene. Three carotenogenic genes, DbPSY, DbLcyB, and DbBCH (ß-carotene hydroxylase) genes were upregulated at later stages, which was well correlated with the carotenoid accumulation. In contrast, DbMADS gene was highly expressed at lag phase with low carotenoid accumulation. Yeast one-hybrid assay and dual-luciferase reporter assay demonstrated that DbMADS could directly bind to the promoters of two carotenogenic genes, DbPSY and DbLcyB, and repress their transcriptions. This study suggested that DbMADS may act as a negative regulator of carotenoid biosynthesis by repressing DbPSY and DbLcyB at the lag phase, which provide new insights into the regulatory mechanisms of carotenoid metabolism in Dunaliella.


Assuntos
Carotenoides , Clorófitas , Carotenoides/metabolismo , Clorófitas/classificação , Clorófitas/genética , Regulação da Expressão Gênica de Plantas , Luteína , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo
6.
Curr Issues Mol Biol ; 45(3): 2213-2229, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36975513

RESUMO

Salmonella enterica is one of the most dangerous foodborne pathogens listed by the World Health Organization. In this study, whole-duck samples were collected at wet markets in five districts in Hanoi, Vietnam, in October 2019 to assess their Salmonella infection rates and evaluate the susceptibility of the isolated strains to antibiotics currently used in the prophylaxis and treatment of Salmonella infection. Based on the antibiotic resistance profiles, eight multidrug resistance strains were whole-genome-sequenced, and their antibiotic resistance genes, genotypes, multi-locus sequence-based typing (MLST), virulence factors, and plasmids were analyzed. The results of the antibiotic susceptibility test indicate that phenotypic resistance to tetracycline and cefazolin was the most common (82.4%, 28/34 samples). However, all isolates were susceptible to cefoxitin and meropenem. Among the eight sequenced strains, we identified 43 genes associated with resistance to multiple classes of antibiotics such as aminoglycoside, beta-lactam, chloramphenicol, lincosamide, quinolone, and tetracycline. Notably, all strains carried the blaCTX-M-55 gene, which confers resistance to third-generation antibiotics including cefotaxime, cefoperazone, ceftizoxime, and ceftazidime, as well as resistance genes of other broad-spectrum antibiotics used in clinical treatment such as gentamicin, tetracycline, chloramphenicol, and ampicillin. Forty-three different antibiotic resistance genes were predicted to be present in the isolated Salmonella strains' genomes. In addition, three plasmids were predicted in two strains, 43_S11 and 60_S17. The sequenced genomes also indicated that all strains carried SPI-1, SPI-2, and SPI-3. These SPIs are composed of antimicrobial resistance gene clusters and thus represent a potential threat to public health management. Taken together, this study highlights the extent of multidrug-resistant Salmonella contamination in duck meat in Vietnam.

7.
J Environ Manage ; 335: 117583, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36848804

RESUMO

The disposal of blue algae (BA) and corn gluten (CG) wastes and the simultaneous recovery of abundant phosphorus (P) and nitrogen (N) by pyrolysis to obtain biochars with high fertility is a promising strategy. However, pyrolysis of BA or CG alone by a conventional reactor cannot reach the target. Herein, we propose a novel MgO-enhanced N and P recovery method by designing a two-zone staged pyrolysis reactor to highly efficiently recover N and P with easily available plant forms in BA and CG. The results show that a 94.58% total phosphorus (TP) retention rate was achieved by means of the special two-zone staged pyrolysis method, in which the effective P (Mg2PO4(OH) and R-NH-P) accounted for 52.9% of TP, while the total nitrogen (TN) reached 4.1 wt%. In this process, stable P was formed first at 400 °C to avoid rapid volatilization and then to form hydroxyl P at 800 °C. Meanwhile, Mg-BA char in the lower zone can efficiently absorb N-containing gas generated by the upper CG, forming dispersible N. This work is of great significance for improving the green utilization value of P and N in BA and CG.


Assuntos
Magnésio , Zea mays , Carvão Vegetal , Fósforo , Nitrogênio , Nutrientes
8.
J Environ Manage ; 329: 117073, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549065

RESUMO

The excess sludge produced by sewage treatment plants can be recycled into energy through pyrolysis, and the byproduct biochar can be used for soil remediation. However, the heavy metals in sludge are retained in biochar after pyrolysis and may cause secondary pollution during its soil application. Herein, a fast copyrolysis method of activated sludge (AS) and apple branches (AT) was proposed to immobilize heavy metals while improving bio-oil yield. The results showed that the heavy metal release from the copyrolyzed biochar was markedly reduced compared with that from the biochar produced through the pyrolysis of AS alone (78% for Cr and 28% for Pb). The kinetic behavior of ion release from different biochars could be described by a first-order kinetic model. The excellent fixation of heavy metals was attributed to complexation by abundant oxygen-containing surface functional groups (-O-, =O, and -CHO) that were mainly donated by AT. Furthermore, high-temperature pyrolysis was conducive to the fixation of metals, and the release of Pb2+ and Cr3+ from the biochar pyrolyzed at 600 °C was approximately 2/3 and 1/10 of that from the biochar pyrolyzed at 400 °C, respectively. A growth experiment on Staphylococcus aureus and Escherichia coli revealed that the toxicity of the copyrolyzed biochar was greatly reduced. This work can provide a method for heavy metal fixation and simultaneous resource recovery from organic wastes.


Assuntos
Malus , Metais Pesados , Esgotos , Chumbo , Carvão Vegetal , Metais Pesados/análise , Solo
9.
Fa Yi Xue Za Zhi ; 39(1): 66-71, 2023 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37038858

RESUMO

Bone development shows certain regularity with age. The regularity can be used to infer age and serve many fields such as justice, medicine, archaeology, etc. As a non-invasive evaluation method of the epiphyseal development stage, MRI is widely used in living age estimation. In recent years, the rapid development of machine learning has significantly improved the effectiveness and reliability of living age estimation, which is one of the main development directions of current research. This paper summarizes the analysis methods of age estimation by knee joint MRI, introduces the current research trends, and future application trend.


Assuntos
Determinação da Idade pelo Esqueleto , Epífises , Epífises/diagnóstico por imagem , Determinação da Idade pelo Esqueleto/métodos , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Articulação do Joelho/diagnóstico por imagem
10.
Fa Yi Xue Za Zhi ; 39(4): 382-387, 2023 Aug 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37859477

RESUMO

OBJECTIVES: To study the virtual reality-pattern visual evoked potential (VR-PVEP) P100 waveform characteristics of monocular visual impairment with different impaired degrees under simultaneous binocular perception and monocular stimulations. METHODS: A total of 55 young volunteers with normal vision (using decimal recording method, far vision ≥0.8 and near vision ≥0.5) were selected to simulate three groups of monocular refractive visual impairment by interpolation method. The sum of near and far vision ≤0.2 was Group A, the severe visual impairment group; the sum of near and far vision <0.8 was Group B, the moderate visual impairment group; and the sum of near and far vision ≥0.8 was Group C, the mild visual impairment group. The volunteers' binocular normal visions were set as the control group. The VR-PVEP P100 peak times measured by simultaneous binocular perception and monocular stimulation were compared at four spatial frequencies 16×16, 24×24, 32×32 and 64×64. RESULTS: In Group A, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 24×24, 32×32 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group B, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 16×16, 24×24 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group C, there was no significant difference between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at all spatial frequencies (P>0.05). There was no significant difference in the P100 peak times measured at all spatial frequencies between simulant visual impairment eyes and simultaneous binocular perception in the control group (P>0.05). CONCLUSIONS: VR-PVEP can be used for visual acuity evaluation of patients with severe and moderate monocular visual impairment, which can reflect the visual impairment degree caused by ametropia. VR-PVEP has application value in the objective evaluation of visual function and forensic clinical identification.


Assuntos
Potenciais Evocados Visuais , Realidade Virtual , Humanos , Visão Ocular , Visão Binocular/fisiologia , Transtornos da Visão/diagnóstico
11.
J Cell Physiol ; 237(2): 1607-1616, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34812495

RESUMO

Dunaliella salina can accumulate a large amount of ß-carotene which is generally considered to be its terminal product of carotenoid metabolism. In this study, it was proved that D. salina has the ketolase (DsBKT) of catalyzing the synthesis of astaxanthin, the downstream products of ß-carotene. Therefore, the reason why D. salina does not synthesize astaxanthin is the purpose of this study. The enzymatic activity of DsBKT was detected by functional complementation assays in Escherichia coli, results showed that DsBKT had efficient ketolase activity toward ß-carotene and zeaxanthin to produce astaxanthin, indicating that there were complete astaxanthin-producing genes in Dunaliella. Unlike the induced expression of Lycopene cyclase (catalyzing ß-carotene synthesis) under salt stress, the expression of DsBKT was very low under both normal and stress conditions, which may be the main reason why D. salina cannot accumulate astaxanthin. On the contrary, with the astaxanthin-rich Haematococcus pluvialis as a control, its BKT gene was significantly upregulated under salt stress. Further study showed that DsBKT promoter had strong promoter ability and could stably drive the expression of ble-egfp in D. salina. Obviously, DsBKT promoter is not the reason of DsBKT not being expressed which may be caused by Noncoding RNA.


Assuntos
Clorófitas , Oxigenases , beta Caroteno , Escherichia coli/genética , Escherichia coli/metabolismo , Oxigenases/genética , Estresse Salino/genética , Xantofilas , beta Caroteno/metabolismo
12.
Altern Ther Health Med ; 28(6): 14-21, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35751892

RESUMO

Context: Diabetes mellitus (DM) represents an emerging epidemic, poses serious threats to human health, and can seriously compromise patients' quality of life (QoL). Currently, no cure exists for DM. Some studies have found that both liraglutide and dapagliflozin have great therapeutic potential in preventing and treating DM and its complications. Objective: The study aimed to examine the impact of liraglutide plus dapagliflozin on high uric acid (UA) and microalbuminuria (MAU) in patients with diabetes mellitus (DM) complicated with metabolic syndrome (MS). Design: The research team designed a randomized controlled trial. Setting: The study took place at the Second Affiliated Hospital of Nanjing Medical University in Nanjing, Jiangsu, China. Participants: Participants were 125 patients with DM complicated with MS who were treated in the outpatient clinic of the endocrinology department at the hospital between January 1, 2020 and December 31, 2021, with 68 in the intervention group and 57 in the control group. Intervention: The intervention and control groups both received 0.6 mg of liraglutide. The intervention group also received 5 mg of dapagliflozin once a day. The dosages were increased at one week after baseline based on the participant's condition. Outcome Measures: Therapeutic effects, glycolipid metabolism, inflammation, uric acid (UA), microalbuminuria (MAU), cardiac function, and quality of life (QoL) were compared between the two groups. Results: Postintervention, the clinical efficacy was significantly higher in the intervention group than in the control group. The intervention group had significantly lower glycolipid metabolism and inflammatory-factor levels than the control group UA and MAU had declined in both groups but were significantly lower in the intervention group. The left ventricular ejection fraction (LVEF) increased and the left ventricular end diastolic diameter (LVEDd) decreased in both groups, but the intervention group had significantly greater changes as compared with those in the control group. The intervention group was also superior to the control group in patients' QoL. Conclusions: Liraglutide plus dapagliflozin has highly therapeutic effect for patients with DM complicated with MS and can effectively reduce UA and MAU levels. The current research team will launch a more comprehensive analysis as soon as possible to obtain the most accurate results.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Síndrome Metabólica , Compostos Benzidrílicos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos , Glicolipídeos/uso terapêutico , Humanos , Liraglutida/uso terapêutico , Síndrome Metabólica/complicações , Síndrome Metabólica/tratamento farmacológico , Qualidade de Vida , Volume Sistólico , Ácido Úrico/uso terapêutico , Função Ventricular Esquerda
13.
Int J Mol Sci ; 23(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35328461

RESUMO

Dihydrouridine (D) is an abundant post-transcriptional modification present in transfer RNA from eukaryotes, bacteria, and archaea. D has contributed to treatments for cancerous diseases. Therefore, the precise detection of D modification sites can enable further understanding of its functional roles. Traditional experimental techniques to identify D are laborious and time-consuming. In addition, there are few computational tools for such analysis. In this study, we utilized eleven sequence-derived feature extraction methods and implemented five popular machine algorithms to identify an optimal model. During data preprocessing, data were partitioned for training and testing. Oversampling was also adopted to reduce the effect of the imbalance between positive and negative samples. The best-performing model was obtained through a combination of random forest and nucleotide chemical property modeling. The optimized model presented high sensitivity and specificity values of 0.9688 and 0.9706 in independent tests, respectively. Our proposed model surpassed published tools in independent tests. Furthermore, a series of validations across several aspects was conducted in order to demonstrate the robustness and reliability of our model.


Assuntos
Algoritmos , Nucleotídeos , Biologia Computacional/métodos , RNA de Transferência , Reprodutibilidade dos Testes
14.
Fa Yi Xue Za Zhi ; 38(3): 350-354, 2022 Jun 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36221829

RESUMO

OBJECTIVES: To reduce the dimension of characteristic information extracted from pelvic CT images by using principal component analysis (PCA) and partial least squares (PLS) methods. To establish a support vector machine (SVM) classification and identification model to identify if there is pelvic injury by the reduced dimension data and evaluate the feasibility of its application. METHODS: Eighty percent of 146 normal and injured pelvic CT images were randomly selected as training set for model fitting, and the remaining 20% was used as testing set to verify the accuracy of the test, respectively. Through CT image input, preprocessing, feature extraction, feature information dimension reduction, feature selection, parameter selection, model establishment and model comparison, a discriminative model of pelvic injury was established. RESULTS: The PLS dimension reduction method was better than the PCA method and the SVM model was better than the naive Bayesian classifier (NBC) model. The accuracy of the modeling set, leave-one-out cross validation and testing set of the SVM classification model based on 12 PLS factors was 100%, 100% and 93.33%, respectively. CONCLUSIONS: In the evaluation of pelvic injury, the pelvic injury data mining model based on CT images reaches high accuracy, which lays a foundation for automatic and rapid identification of pelvic injuries.


Assuntos
Algoritmos , Máquina de Vetores de Suporte , Teorema de Bayes , Mineração de Dados , Análise dos Mínimos Quadrados
15.
Beilstein J Org Chem ; 18: 1625-1628, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530530

RESUMO

An approach to aberrarone, an antimalarial diterpenoid natural product with tetracyclic skeleton is reported. Key to the stereoselective preparation of the 6-5-5 tricyclic skeleton includes the mediation of Nagata reagent for constructing the C1 all-carbon quaternary centers and gold-catalyzed cyclopentenone synthesis through C-H insertion.

16.
Liver Int ; 41(7): 1498-1508, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33486874

RESUMO

BACKGROUND & AIMS: Nucleotides with add-on interferon treatment (NUC-IFN) provide significantly higher rates of hepatitis B surface antigen (HBsAg) loss in patients with chronic hepatitis B (CHB). This study aimed to investigate the sustainability of HBsAg loss and the prevention of clinical relapse. METHODS: Patients with CHB who achieved HBsAg loss and HBV DNA levels <20 IU/ml after IFN or NUC-IFN therapy were enrolled and followed up for 96 weeks. The primary outcome was HBsAg negativity without viremia at week 96. Secondary outcomes included virological or clinical relapse and predictors of relapse. RESULTS: 420 patients were included in intention-to-treat analysis with 290 and 130 in the IFN and NUC-IFN groups respectively. At week 96, the intention-to-treat analysis revealed similar outcomes between groups, including HBsAg seroreversion (24.83% vs. 23.08%, P = .70), viremia (16.90% vs 13.08%, P = .32) and clinical relapse (11.38% vs 10.00%, P = .68); the per-protocol analyses also showed HBsAg seroreversion, viremia and clinical relapse in IFN group (15.50%, 6.59% and 0.39%) did not differ from those in NUC-IFN group (15.25%, 4.24% and 0.85%, P > .05). These outcomes were similar between patients who received entecavir and those who received telbivudine/lamivudine/adefovir before the combination therapy. In NUC-IFN-treated patients, fibrosis regression was observed at week 96. Baseline HBsAb negativity was independent predictors of HBsAg sero-reversion and recurrence of viremia in IFN treated group. CONCLUSION: NUC-IFN and IFN therapies are equally effective in achieving sustained functional cure and fibrosis regression. (ClinicalTrials.gov, Number NCT02336399).


Assuntos
Hepatite B Crônica , Hepatite B , Antivirais/uso terapêutico , China , DNA Viral , Hepatite B/tratamento farmacológico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Recidiva Local de Neoplasia , Polietilenoglicóis/uso terapêutico , Resultado do Tratamento
17.
Int J Mol Sci ; 22(13)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34281260

RESUMO

Males have a higher risk for cardiovascular diseases (CVDs) than females. Ambient fine particulate matter (PM) exposure increases CVD risk with increased reactive oxygen species (ROS) production and oxidative stress. Endothelial progenitor cells (EPCs) are important to vascular structure and function and can contribute to the development of CVDs. The aims of the present study were to determine if sex differences exist in the effect of PM exposure on circulating EPCs in mice and, if so, whether oxidative stress plays a role. Male and female C57BL/6 mice (8-10 weeks old) were exposed to PM or a vehicle control for six weeks. ELISA analysis showed that PM exposure substantially increased the serum levels of IL-6 and IL-1ß in both males and females, but the concentrations were significantly higher in males. PM exposure only increased the serum levels of TNF-α in males. Flow cytometry analysis demonstrated that ROS production was significantly increased by PM treatment in males but not in females. Similarly, the level of circulating EPCs (CD34+/CD133+ and Sca-1+/Flk-1+) was significantly decreased by PM treatment in males but not in females. Antioxidants N-acetylcysteine (NAC) effectively prevented PM exposure-induced ROS and inflammatory cytokine production and restored circulating EPC levels in male mice. In sharp contrast, circulating EPC levels remained unchanged in female mice with PM exposure, an effect that was not altered by ovariectomy. In conclusion, PM exposure selectively decreased the circulating EPC population in male mice via increased oxidative stress without a significant impact on circulating EPCs in females independent of estrogen.


Assuntos
Células Progenitoras Endoteliais/efeitos dos fármacos , Células Progenitoras Endoteliais/metabolismo , Material Particulado/toxicidade , Acetilcisteína/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Citocinas/sangue , Células Progenitoras Endoteliais/patologia , Estrogênios/metabolismo , Feminino , Mediadores da Inflamação/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores Sexuais
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 671-678, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323048

RESUMO

OBJECTIVE: To establish a classification method to identify different male lineages in a large population, to study the distribution patterns of Y-STR loci mismatches among Han Chinese male lineage members and to explore the mismatch probability distribution among the members with different meiosis intervals in the family. METHODS: Peripheral blood samples of 269 male individuals from 12 lineages in Han Chinese population and 45 unrelated male individuals were collected. Then, Yfiler Plus TM and ZGWZ FSY or Yfiler Platinum amplification kits were used, obtaining 314 Y-STR haplotypes. The Y-STR haplotype with 3 or more repetitions were selected as the main haplotype, in which the largest number was selected as the first data center. According to the standard of Y-STR genotype, those with mismatches within five loci and six steps were clustered and merged. Then, the main haplotype of the largest number in the remaining data was taken as the second data center, and cluster analysis is carried out in turn until there is no main haplotype remained. Pair comparison was conducted between lineage members and unrelated individuals, and the mismatch distribution among lineage members and unrelated individuals was calculated respectively. The average mismatch rate of each locus was subsequently calculated, as well as the mismatch probability distribution among members with different meiosis intervals within the lineage. RESULTS: 269 out of the 314 individuals were divided into 12 groups by cluster analysis method, accomplishing 100% accuracy between the cluster groups thus identified and the 12 known lineages. The remaining 45 unrelated individuals were scattered. The mismatch loci was within 0-7 loci and 0-7 steps among lineage members and the mismatch between unrelated individuals was at least 11 loci and 15 steps. The mismatch loci with the largest number of one-step and two-step mismatch were different in each lineage and had features that were specific to each lineage. The minimum mutation count and average mismatch rate of each locus were significantly correlated with the mutation rate. Two individuals with no mismatch had a 19.7% probability of 1 meiosis interval and a 71.2% probability of less than 6 meiosis interval. Two individuals with 3 loci mismatches had a 65.2% probability of more than 10 meiosis intervals. CONCLUSION: The cluster analysis method based on main haplotypes provided in this paper can quickly and effectively differentiate large male lineage samples. The clustering method and the mismatch probability distribution of different meiosis intervals obtained thus can provide new ideas for research and screening instruments, and important reference for lineage investigation, data analysis and practical application of Y-STR database in the future.


Assuntos
Cromossomos Humanos Y , Teorema de Bayes , China , Cromossomos Humanos Y/genética , Genótipo , Haplótipos , Humanos , Masculino , Mutação
19.
Angew Chem Int Ed Engl ; 60(31): 16911-16916, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34060186

RESUMO

The development of new-type memristors with special performance is of great interest. Herein, an inorganic-organic hybrid crystalline polyoxometalate (POM) with usual dynamic structures is reported and used as active material for fabricating memristor with unique temperature-regulated resistive switching behaviors. The hybrid POM not only exhibits tunable thermochromic properties, but also thermal-induced reversible aggregation and disaggregation reactions, leading to reversible structural transformations in SCSC fashion. Further, the memory device using the hybrid POM as active layer exhibits uncommon performance, which can keep resistive switching silent in the low temperature range of 30-150 °C, but show nonvolatile memory behavior in the high temperature range of 150-270 °C. Particularly, the silent and working states at three special temperatures (30, 150 and 270 °C) can be monitored by chromism. The correlation between structure and resistive switching property of the material has been discussed. The work demonstrates that crystalline inorganic-organic hybrid POMs are promising materials for making memristors with superior performance.

20.
J Cell Mol Med ; 24(1): 886-898, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31742908

RESUMO

MG53 is an important membrane repair protein and partially protects bone marrow multipotent adult progenitor cells (MAPCs) against oxidized low-density lipoprotein (ox-LDL). The present study was to test the hypothesis that the limited protective effect of MG53 on MAPCs was due to ox-LDL-induced reduction of MG53. MAPCs were cultured with and without ox-LDL (0-20 µg/mL) for up to 48 hours with or without MG53 and antioxidant N-acetylcysteine (NAC). Serum MG53 level was measured in ox-LDL-treated mice with or without NAC treatment. Ox-LDL induced significant membrane damage and substantially impaired MAPC survival with selective inhibition of Akt phosphorylation. NAC treatment effectively prevented ox-LDL-induced reduction of Akt phosphorylation without protecting MAPCs against ox-LDL. While having no effect on Akt phosphorylation, MG53 significantly decreased ox-LDL-induced membrane damage and partially improved the survival, proliferation and apoptosis of MAPCs in vitro. Ox-LDL significantly decreased MG53 level in vitro and serum MG53 level in vivo without changing MG53 clearance. NAC treatment prevented ox-LDL-induced MG53 reduction both in vitro and in vivo. Combined NAC and MG53 treatment significantly improved MAPC survival against ox-LDL. These data suggested that NAC enhanced the protective effect of MG53 on MAPCs against ox-LDL through preventing ox-LDL-induced reduction of MG53.


Assuntos
Acetilcisteína/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipoproteínas LDL/toxicidade , Proteínas de Membrana/metabolismo , Células-Tronco Multipotentes/efeitos dos fármacos , Fatores de Proteção , Animais , Apoptose , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Ciclo Celular , Proliferação de Células , Sequestradores de Radicais Livres/farmacologia , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/patologia , Ratos
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