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1.
Nat Commun ; 15(1): 3871, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719862

RESUMO

Temperature is one of the seven fundamental physical quantities. The ability to measure temperatures approaching absolute zero has driven numerous advances in low-temperature physics and quantum physics. Currently, millikelvin temperatures and below are measured through the characterization of a certain thermal state of the system as there is no traditional thermometer capable of measuring temperatures at such low levels. In this study, we develop a kind of diamond with sp2-sp3 composite phase to tackle this problem. The synthesized composite phase diamond (CPD) exhibits a negative temperature coefficient, providing an excellent fit across a broad temperature range, and reaching a temperature measurement limit of 1 mK. Additionally, the CPD demonstrates low magnetic field sensitivity and excellent thermal stability, and can be fabricated into probes down to 1 micron in diameter, making it a promising candidate for the manufacture of next-generation cryogenic temperature sensors. This development is significant for the low-temperature physics researches, and can help facilitate the transition of quantum computing, quantum simulation, and other related technologies from research to practical applications.

2.
Cardiovasc Diabetol ; 23(1): 164, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724987

RESUMO

Dynamin-related protein 1 (Drp1) is a crucial regulator of mitochondrial dynamics, the overactivation of which can lead to cardiovascular disease. Multiple distinct posttranscriptional modifications of Drp1 have been reported, among which S-nitrosylation was recently introduced. However, the detailed regulatory mechanism of S-nitrosylation of Drp1 (SNO-Drp1) in cardiac microvascular dysfunction in diabetes remains elusive. The present study revealed that mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) was consistently upregulated in diabetic cardiomyopathy (DCM) and promoted SNO-Drp1 in cardiac microvascular endothelial cells (CMECs), which in turn led to mitochondrial dysfunction and cardiac microvascular disorder. Further studies confirmed that MAP4K4 promoted SNO-Drp1 at human C644 (mouse C650) by inhibiting glutathione peroxidase 4 (GPX4) expression, through which MAP4K4 stimulated endothelial ferroptosis in diabetes. In contrast, inhibition of MAP4K4 via DMX-5804 significantly reduced endothelial ferroptosis, alleviated cardiac microvascular dysfunction and improved cardiac dysfunction in db/db mice by reducing SNO-Drp1. In parallel, the C650A mutation in mice abolished SNO-Drp1 and the role of Drp1 in promoting cardiac microvascular disorder and cardiac dysfunction. In conclusion, our findings demonstrate that MAP4K4 plays an important role in endothelial dysfunction in DCM and reveal that SNO-Drp1 and ferroptosis activation may act as downstream targets, representing potential therapeutic targets for DCM.


Assuntos
Cardiomiopatias Diabéticas , Dinaminas , Células Endoteliais , Camundongos Endogâmicos C57BL , Transdução de Sinais , Animais , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/fisiopatologia , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/enzimologia , Cardiomiopatias Diabéticas/etiologia , Humanos , Dinaminas/metabolismo , Dinaminas/genética , Masculino , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/enzimologia , Células Endoteliais/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Ferroptose/efeitos dos fármacos , Modelos Animais de Doenças , Células Cultivadas , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/enzimologia , Camundongos , Processamento de Proteína Pós-Traducional , Circulação Coronária , Peptídeos e Proteínas de Sinalização Intracelular
3.
Artigo em Inglês | MEDLINE | ID: mdl-38728583

RESUMO

Recently, a meta-analysis has shown that a potentially functional genetic polymorphism (rs7158663 A > G) on the cancer-associated lncRNA MEG3 is associated with the risk of many types of cancer. Given the important role of MEG3 in the development of hepatocellular carcinoma (HCC), the current study evaluated the association of the rs7158663 genetic polymorphism with HCC risk. A total of 271 HCC patients and 267 healthy individuals were included in the current case-control study. Direct sequencing was used to detect the rs7158663 locus genotype of the included individuals. The case-control study showed that the MEG3 rs7158663 genetic polymorphism was associated with the increased risk of developing HCC [GA vs. GG: OR = 1.63, 95% CI = 1.14-2.34, p = 0.009; AA vs. GG: OR = 2.10, 95% CI = 1.10-4.08, p = 0.03; (GA + AA) vs. GG: OR = 1.70, 95% CI = 1.21-2.40, p = 0.003; A vs. G: OR = 1.53, 95% CI = 1.17-2.00, p = 0.002]. In addition, the genotype-tissue expression showed that the rs7158663 AA or GA genotype was associated with reduced MEG3 expression. Bioinformatic analysis showed that the rs7158663 genetic polymorphism not only affects the binding of transcription factors but also interacts with multiple genes through chromatin loops. In summary, the current findings suggest that the rs7158663 genetic polymorphism affecting MEG3 expression is associated with HCC risk and may serve as a marker of genetic susceptibility to HCC. However, the specific molecular mechanisms of the rs7158663 genetic polymorphism in the development of HCC need to be further revealed.

4.
Small ; : e2401742, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721985

RESUMO

There is a growing demand for thermal management materials in electronic fields. Aerogels have attracted interest due to their extremely low density and extraordinary thermal insulation properties. However, the application of aerogels is limited by high production costs and the requirement that aerogel structures not be load-bearing. In this study, mullite-reinforced SiC-based aerogel composite (MR-SiC AC) is prepared through 3D printing combined with in situ growth of SiC nanowires in post processing. The fabricated MR-SiC AC not only has ultra-low thermal conductivity (0.021 W K m-1) and high porosity (90.0%), but also a high Young's modulus (24.4 MPa) and high compressive strength (1.65 MPa), both exceeding the measurements of existing resilient aerogels by an order of magnitude. These properties make MR-SiC AC an ideal solution for the precision thermal management of lightweight structures having complex geometry for functional devices.

5.
J Autoimmun ; 146: 103235, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38696926

RESUMO

Soluble components secreted by Tfh cells are critical for the germinal center responses. In this study, we investigated whether Tfh cells could regulate the B-cell response by releasing small extracellular vesicles (sEVs). Our results showed that Tfh cells promote B-cell differentiation and antibody production through sEVs and that CD40L plays a crucial role in Tfh-sEVs function. In addition, increased Tfh-sEVs were found in mice with collagen-induced arthritis (CIA). Adoptive transfer of Tfh cells significantly exacerbated the severity of CIA; however, the effect of Tfh cells on exacerbating the CIA process was significantly diminished after inhibiting sEVs secretion. Moreover, the levels of plasma Tfh-like-sEVs and CD40L expression on Tfh-like-sEVs in RA patients were significantly higher than those in healthy subjects. In summary, Tfh cell-derived sEVs can enhance the B-cell response, and exacerbate the procession of autoimmune arthritis.

6.
Biomed J ; : 100747, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735535

RESUMO

BACKGROUND: Transthoracic echocardiography (TTE) is currently recognized as the potential first-line imaging test for patients with suspected acute type A aortic syndrome (AAAS). Direct TTE sign for detecting AAAS is positive if there is an intimal flap separating two aortic lumens or aortic wall thickening seen in the ascending aorta. Indirect TTE sign indicates high-risk features of AAAS, such as aortic root dilatation, pericardial effusion, and aortic regurgitation. Our aim is to summarize the existing clinical evidence regarding the diagnostic accuracy of TTE and to evaluate its potential role in the management of patients with suspected AAAS. METHODS: We included prospective or retrospective diagnostic cohort studies, written in any language, that specifically focused on using TTE to diagnose AAAS from databases such as PubMed, EMBASE, MEDLINE, and the Cochrane Library. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio [1], and hierarchical summary receiver-operating characteristic (HSROC) curve were calculated for TTE in diagnosing AAAS. We applied Quality Assessment of Diagnostic Accuracy (QUADAS-2) tool and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) quality assessment criteria. RESULTS: Ten studies (2886 patients) were included in the meta-analysis. The pooled sensitivity and specificity of direct TTE signs were 58% (95% CI, 38-76%) and 94% (95% CI, 89-97%). For any TTE signs, the pooled sensitivity and specificity were 91% (95% CI, 85-94%) and 74% (95% CI, 61-84%). The diagnostic accuracy of direct TTE signs was significantly higher than that of any TTE signs, as measured by the area under the HSROC curve [0.95 (95% CI, 0.92-0.96) vs. 0.87 (95% CI, 0.84-0.90)] in four studies. CONCLUSIONS: Our study suggests that TTE could serve as the initial imaging test for patients with suspected AAAS. Given its high specificity, the presence of direct TTE signs may indicate AAAS, whereas the absence of any TTE signs, combined with low clinical suspicion, could suggest a lower likelihood of AAAS.

7.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38732143

RESUMO

This study explores low-intensity extracorporeal shock wave therapy (LiESWT)'s efficacy in alleviating detrusor hyperactivity with impaired contractility (DHIC) induced by ovarian hormone deficiency (OHD) in ovariectomized rats. The rats were categorized into the following four groups: sham group; OVX group, subjected to bilateral ovariectomy (OVX) for 12 months to induce OHD; OVX + SW4 group, underwent OHD for 12 months followed by 4 weeks of weekly LiESWT; and OVX + SW8 group, underwent OHD for 12 months followed by 8 weeks of weekly LiESWT. Cystometrogram studies and voiding behavior tracing were used to identify the symptoms of DHIC. Muscle strip contractility was evaluated through electrical-field, carbachol, ATP, and KCl stimulations. Western blot and immunofluorescence analyses were performed to assess the expressions of various markers related to bladder dysfunction. The OVX rats exhibited significant bladder deterioration and overactivity, alleviated by LiESWT. LiESWT modified transient receptor potential vanilloid (TRPV) channel expression, regulating calcium concentration and enhancing bladder capacity. It also elevated endoplasmic reticulum (ER) stress proteins, influencing ER-related Ca2+ channels and receptors to modulate detrusor muscle contractility. OHD after 12 months led to neuronal degeneration and reduced TRPV1 and TRPV4 channel activation. LiESWT demonstrated potential in enhancing angiogenic remodeling, neurogenesis, and receptor response, ameliorating DHIC via TRPV channels and cellular signaling in the OHD-induced DHIC rat model.


Assuntos
Modelos Animais de Doenças , Tratamento por Ondas de Choque Extracorpóreas , Contração Muscular , Canais de Cátion TRPV , Bexiga Urinária , Animais , Feminino , Ratos , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Tratamento por Ondas de Choque Extracorpóreas/métodos , Bexiga Urinária/fisiopatologia , Bexiga Urinária/metabolismo , Bexiga Urinária Hiperativa/terapia , Bexiga Urinária Hiperativa/metabolismo , Bexiga Urinária Hiperativa/fisiopatologia , Bexiga Urinária Hiperativa/etiologia , Ovariectomia , Ratos Sprague-Dawley , Ovário/metabolismo
8.
Sci Adv ; 10(16): eadh3425, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38630810

RESUMO

Drosophila melanogaster is a widely used model organism for studying environmental adaptation. However, the genetic diversity of populations in Asia is poorly understood, leaving a notable gap in our knowledge of the global evolution and adaptation of this species. We sequenced genomes of 292 D. melanogaster strains from various ecological settings in China and analyzed them along with previously published genome sequences. We have identified six global genetic ancestry groups, despite the presence of widespread genetic admixture. The strains from China represent a unique ancestry group, although detectable differentiation exists among populations within China. We deciphered the global migration and demography of D. melanogaster, and identified widespread signals of adaptation, including genetic changes in response to insecticides. We validated the effects of insecticide resistance variants using population cage trials and deep sequencing. This work highlights the importance of population genomics in understanding the genetic underpinnings of adaptation, an effort that is particularly relevant given the deterioration of ecosystems.


Assuntos
Drosophila melanogaster , Metagenômica , Animais , Drosophila melanogaster/genética , Variação Genética , Ecossistema , África Subsaariana , China
9.
APL Bioeng ; 8(2): 026105, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38680995

RESUMO

The viscoelasticity of monoclonal antibodies (mAbs) is important during their production, formulation, and drug delivery. High concentration mAbs can provide higher efficacy therapeutics (e.g., during immunotherapy) and improved efficiency during their production (economy of scale during processing). Two humanized mAbs were studied (mAb-1 and mAb-2) with differing isoelectric points. Using high speed particle tracking microrheology, we demonstrated that the mAb solutions have significant viscoelasticities above concentrations of 40 mg/ml. Power law viscoelasticity was observed over the range of time scales (10-4-1 s) probed for the high concentration mAb suspensions. The terminal viscosity demonstrated an exponential dependence on mAb concentration (a modified Mooney relationship) as expected for charged stabilized Brownian colloids. Gelation of the mAbs was explored by lowering the pH of the buffer and a power law scaling of the gelation transition was observed, i.e., the exponent of the anomalous diffusion of the probe particles scaled inversely with the gelation time.

10.
Gastroenterol. hepatol. (Ed. impr.) ; 47(4): 366-376, Abr. 2024. graf
Artigo em Inglês | IBECS | ID: ibc-231803

RESUMO

Background: Inflammasome activation is known to be involved in nonalcoholic steatohepatitis (NASH). Vinpocetine is a derivative of vincamine and is reported to suppress the activation of inflammasome. Methods: This study explored the therapeutical potential of Vinpocetine on NASH. Mice were fed with a choline-deficient (MCD) or chow diet in the presence or absence of Vinpocetine for 8 weeks. H&E staining and biochemical assays were determined to evaluate the hepatic steatosis and fibrosis symptoms. In addition, primary hepatocytes and Kupffer cells were isolated and induced by MCD or lipopolysaccharides/cholesterol crystals with or without Vinpocetine. ELISAs, qPCR, and Western blotting were applied to determine the levels of NASH-related biomarkers in both in vivo mouse model and in vitro cell models. Results: Treatment of Vinpocetine did not cause observable side effects against and MCD-induced cells and mouse NASH model. However, treatment of Vinpocetine ameliorated hepatic steatosis and fibrosis and suppressed the levels of alanine transaminase and aspartate transferase in the mouse NASH model. In addition, treatment of Vinpocetine suppressed the mRNA and protein levels of inflammasome components both in vitro and in vivo. Conclusion: Vinpocetine suppressed NASH in mice by mediating inflammasome components via nuclear factor κB signaling. (AU)


Antecedentes: Se sabe que la activación del inflamasoma está implicada en la esteatohepatitis no alcohólica (EHNA). La vinpocetina es un derivado de la vincamina que, según los informes, suprime la activación del inflamasoma. Métodos: Este estudio exploró el potencial terapéutico de la vinpocetina en la EHNA. Durante 8 semanas se alimentó a ratones con una dieta deficiente en colina (MCD) o con una dieta chow en presencia o ausencia de vinpocetina. Se realizaron tinciones de H&E y ensayos bioquímicos para evaluar los síntomas de esteatosis hepática y fibrosis. Además, se aislaron hepatocitos primarios y células de Kupffer y se indujeron mediante MCD o cristales de lipopolisacáridos/colesterol con o sin vinpocetina. Se aplicaron ELISA, qPCR y Western blotting para determinar los niveles de biomarcadores relacionados con la EHNA tanto en el modelo de ratón in vivo como en los modelos celulares in vitro. Resultados: El tratamiento con vinpocetina no causó efectos secundarios observables contra las células y el modelo de ratón de EHNA inducidos por MCD. Sin embargo, el tratamiento con vinpocetina mejoró la esteatosis hepática y la fibrosis y suprimió los niveles de alanina transaminasa y de aspartato transferasa en el modelo de EHNA de ratón. Además, el tratamiento con vinpocetina suprimió los niveles de ARNm y proteínas de los componentes del inflamasoma tanto in vitro como in vivo. Conclusiones: La vinpocetina suprimió la EHNA en ratones por mediación de los componentes del inflamasoma a través de la señalización del factor nuclear κB. (AU)


Assuntos
Camundongos , Inflamassomos , Inflamação , Vincamina , Fígado Gorduroso , Fibrose , Hepatócitos , Células de Kupffer
11.
Talanta ; 275: 126122, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38663063

RESUMO

Hydrogel biosensors present numerous advantages in food safety analysis owing to their remarkable biocompatibility, cargo-loading capabilities and optical properties. However, the current drawbacks (slow target responsiveness and poor mechanical strength) restricted their further utilization at on-site detection of targets. To address these challenges, a DNA-functionalized cryogel with hierarchical pore structures is constructed to improve the reaction rate and the robustness of hydrogel biosensor. During cryogel preparation, ice crystals serve as templates, shaping interconnected hierarchical microporous structures to enhance mass transfer for faster responses. Meanwhile, in the non-freezing zone, concentrated monomers create a dense cross-linked network, strengthening cryogel matrix strength. Accordingly, a colorimetric biosensor based on DNA cryogel has been developed as a proof of concept for rapid detection of aflatoxin B1 (AFB1) in food samples, and an excellent analytical performance was obtained under the optimized conditions with a low detection limit (1 nM), broad detection range (5-100 nM), satisfactory accuracy and precision (recoveries, 81.2-112.6 %; CV, 2.75-5.53 %). Furthermore, by integrating with a smartphone sensing platform, a portable device was created for rapid on-site measurement of target within 45 min, which provided some insight for hydrogel biosensors design.

12.
BMJ Open ; 14(4): e077808, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38643009

RESUMO

OBJECTIVE: We aimed to explore the association between the leucocyte telomere length (LTL) and erectile dysfunction (ED) among a nationally representative sample of US adults. DESIGN: Secondary population-based study. SETTING: The National Health and Nutrition Examination Survey (NHANES) (2001-2002). PARTICIPANTS: A total of 1694 male participants were extracted from the NHANES database for 2001-2002. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary focus of the study was to determine the association between the LTL and ED, using multivariate logistic regression and restricted cubic spline models for examination. The secondary outcome measures involved conducting stratified subgroup analyses to exclude interactions of different variables with the LTL. RESULTS: Participants with ED had shorter LTLs than those without ED (p<0.05). After adjusting for confounding factors, compared with the reference lowest LTL quartile, the ORs and 95% CIs for the second, third and fourth LTL quartiles were (OR 1.51; 95% CI 1.01 to 2.26), (OR 1.79; 95% CI 1.24 to 2.58) and (OR 1.25; 95% CI 0.74 to 2.11), respectively. In addition, restricted cubic splines showed an inverted J-curve relationship between the LTL and ED. At an LTL of 1.037, the curve showed an inflection point. The ORs (95% CI) of ED on the left and right sides of the inflection point were (OR 1.99; 95% CI 0.39 to 10.20; p=0.385) and (OR 0.17; 95% CI 0.03 to 0.90; p=0.039). CONCLUSION: Our results demonstrated an inverted J-curve relationship between the LTL and ED. When the LTL was ≥1.037, the incidence of ED decreased with increasing LTL.


Assuntos
Disfunção Erétil , Adulto , Humanos , Masculino , Disfunção Erétil/epidemiologia , Disfunção Erétil/genética , Inquéritos Nutricionais , Telômero , Leucócitos , Modelos Logísticos
13.
J Environ Sci (China) ; 143: 1-11, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38644008

RESUMO

Potential health risks related to environmental endocrine disruptors (EEDs) have aroused research hotspots at the forefront of water treatment technologies. Herein, nitrogen-doped titanium dioxide/schwertmannite nanocomposites (N-TiO2/SCH) have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes. Due to the sustainable Fe(III)/Fe(II) conversion induced by photoelectrons, as-prepared N-TiO2/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A (BPA; ca. 100% within 60 min under visible irradiation) in a wide pH range of 3.0-7.8, which is significantly higher than that of the pristine schwertmannite (ca. 74.5%) or N-TiO2 (ca. 10.8%). In this photo-Fenton system, the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical (•OH) and singlet oxygen (1O2). Moreover, the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses. This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts, but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.


Assuntos
Compostos Benzidrílicos , Compostos de Ferro , Nanocompostos , Nitrogênio , Fenóis , Titânio , Poluentes Químicos da Água , Titânio/química , Compostos Benzidrílicos/química , Fenóis/química , Nanocompostos/química , Poluentes Químicos da Água/química , Nitrogênio/química , Catálise , Ferro/química , Peróxido de Hidrogênio/química , Disruptores Endócrinos/química , Purificação da Água/métodos
15.
J Sci Food Agric ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597278

RESUMO

BACKGROUND: Browning is the key problem hindering the industrialization of pear wine. The use of high-yield glutathione Saccharomyces cerevisiae in the fermentation of pear wine can inhibit browning. Glutathione reductase (GR) can ensure the reduction of glutathione. Spore immobilization of enzymes is a new technology. It is a new attempt to apply spore-immobilized GR in combination with high-yield glutathione S. cerevisiae to inhibit browning of pear wine. RESULTS: Saccharomyces cerevisiae spore immobilization enzyme technology was used to immobilize GR in the spores of mutant S. cerevisiae dit1∆, osw2∆ and chs3∆ and wild-type S. cerevisiae. The enzyme activity of GR immobilized by chs3∆ spores was the highest of 3.08 U mg-1 min-1. The chs3∆ spore-immobilized GR had certain resistance to ethanol, citric acid, sucrose, glucose and proteinase K. Electron microscopy analysis showed that the spore wall of chs3∆ had moderate size holes, which might be the main reason why it immobilized GR with the highest enzyme activity. And the GR was immobilized between the prespore membrane and mannoprotein layer of the spore wall. When chs3∆ spore-immobilized GR (chs3∆-GR) was added to Dangshan pear wine fermented by high-yield glutathione S. cerevisiae JN32-9, the presence of chs3∆-GR could further protect amino acids, polyphenols and glucose from oxidation, thereby reducing the browning of the pear wine during storage by 47.32%. CONCLUSION: GR immobilized by S. cerevisiae spores was effective in inhibiting the browning of pear wine. The method was simple, green and effective and did not increase the production cost of pear wine. © 2024 Society of Chemical Industry.

16.
Food Microbiol ; 121: 104522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637084

RESUMO

Purine is mainly culprit of hyperuricemia (HUA) and gout, which is widely present in Huangjiu in the form of free bases. Bacterial succession plays an important role in quality control in Huangjiu. The correlation between the purine compound content and the bacterial communities during the fermentation process has not yet been evaluated. In this study, high-throughput sequencing (HTS) technology was used to monitor the bacterial community composition of Huangjiu at different fermentation stages. The correlation between the bacterial community and the contents of physicochemical properties and purine compounds were evaluated using the Spearman analysis method. The key enzymes of purine metabolism pathway in the microbial community were analyzed by bioinformatics using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt). The results showed that the purine content in Huangjiu increased gradually in 0∼9d of fermentation (21.05-65.71 mg/L), and stabilized gradually in 12∼18d (65.63-69.55 mg/L), while the abundance of lactic acid bacteria (LAB) of bacterial microbial flora were increased (0∼9d) and then stabilized (12∼18d). Moreover, Lactobacillus acetotolerans and Lactobacillus helveticus were highly correlated positively with purine contents, while Limosilactobacillus fermentum and Lactiplantibacillus plantarum were correlated negatively. In addition, the dominant strains of bacteria were involved in the metabolism of purine, and the key enzymes for purine compound synthesis were more abundant than that for purine degradation. This study is helpful to scientifically understand the formation mechanism of purines, providing a basis for screening functional strains of purine degrading to accurately regulate purine level in Huangjiu.


Assuntos
Bactérias , Purinas , Fermentação , Filogenia , Purinas/metabolismo
17.
Langmuir ; 40(15): 8115-8125, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38563662

RESUMO

Core-shell composite abrasive particles are a topic of great interest in surface finishing. It is important to explore the preparation technology and performance parameters associated with them. In this paper, a core-shell composite abrasive particle made of polystyrene and cerium oxide (PS&CeO2, CSPC), which is rigid on the outside and flexible on the inside, is proposed. The microstructure, physical phase characteristics, and mechanical properties of the inner core and composite abrasive particles are investigated. PS microspheres and CSPC composite abrasive particles with different structural features were prepared through a series of experiments, morphological observations, and physical and chemical characterization experiments. Their microstructures and physical phase properties were investigated. The indentation load curves of the PS microspheres and CSPC composite abrasive samples were measured by using an atomic force microscope. The analysis focused on the effects of various dimensional and structural parameters on the modulus of elasticity of both PS microspheres and CSPC composite abrasive particles. The analysis shows that the experimentally prepared PS microspheres have good dispersion, a smooth surface, and a uniform particle size distribution. The prepared CSPC composite abrasive particles are regular spheres with rough, rice-like surfaces, low modulus of elasticity, and overall nonrigid and soft elastic properties. The results of this paper can provide a guide for the preparation technology, performance regulation, and application of polymer microspheres and core-shell composite abrasive particles in CMP.

18.
Chemphyschem ; : e202400052, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629246

RESUMO

A new group of BF3 complexing phosphate/phosphonate ionic liquids (ILs) [Emim][X(BF3)2] (X = dimethyl phosphate, diethyl phosphate, methyl phosphonate, and ethyl phosphonate) were synthesized and characterized. Key thermophysical properties of the new complex ionic liquids, including density, viscosity, conductivity, surface tension, solid-liquid phase transition, and thermal stability were determined and compared with those of [Emim][X]. Some other important thermophysical properties such as isobaric thermal expansion coefficient, molecular volume, standard molar entropy, and lattice potential energy were obtained from measured density data, and the free volume was estimated by a linear equation presented in this article, while critical temperature, normal boiling temperature, and enthalpy of vaporization were estimated from measured surface tension and density data. Furthermore, Fragility study shows that [Emim][X(BF3)2] could be considered as metallic glass-forming liquids, while [Emim][X] could be considered as extremely fragile liquids. The ionicity of [Emim][X(BF3)2] was predicted by Walden rule, and the result shows that these ILs fit well with Walden law. The key features of these complex ILs are their extremely low glass transition (-95.33~-98.46 ℃) without melting, considerably low viscosities (33.876~58.117 mPa·s), and high values of free volume fraction (comparable to [Omim][BF4], [Emim][NTf2], and [Emim][TCB]).

19.
Genet Sel Evol ; 56(1): 26, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565986

RESUMO

BACKGROUND: Chinese indigenous sheep are valuable resources with unique features and characteristics. They are distributed across regions with different climates in mainland China; however, few reports have analyzed the environmental adaptability of sheep based on their genome. We examined the variants and signatures of selection involved in adaptation to extreme humidity, altitude, and temperature conditions in 173 sheep genomes from 41 phenotypically and geographically representative Chinese indigenous sheep breeds to characterize the genetic basis underlying environmental adaptation in these populations. RESULTS: Based on the analysis of population structure, we inferred that Chinese indigenous sheep are divided into four groups: Kazakh (KAZ), Mongolian (MON), Tibetan (TIB), and Yunnan (YUN). We also detected a set of candidate genes that are relevant to adaptation to extreme environmental conditions, such as drought-prone regions (TBXT, TG, and HOXA1), high-altitude regions (DYSF, EPAS1, JAZF1, PDGFD, and NF1) and warm-temperature regions (TSHR, ABCD4, and TEX11). Among all these candidate genes, eight ABCD4, CNTN4, DOCK10, LOC105608545, LOC121816479, SEM3A, SVIL, and TSHR overlap between extreme environmental conditions. The TSHR gene shows a strong signature for positive selection in the warm-temperature group and harbors a single nucleotide polymorphism (SNP) missense mutation located between positions 90,600,001 and 90,650,001 on chromosome 7, which leads to a change in the protein structure of TSHR and influences its stability. CONCLUSIONS: Analysis of the signatures of selection uncovered genes that are likely related to environmental adaptation and a SNP missense mutation in the TSHR gene that affects the protein structure and stability. It also provides information on the evolution of the phylogeographic structure of Chinese indigenous sheep populations. These results provide important genetic resources for future breeding studies and new perspectives on how animals can adapt to climate change.


Assuntos
Genoma , Seleção Genética , Ovinos/genética , Animais , China , Análise de Sequência de DNA , Altitude , Polimorfismo de Nucleotídeo Único
20.
BMC Med Educ ; 24(1): 359, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561709

RESUMO

BACKGROUND: To investigate the knowledge, attitudes, and practice (KAP) toward postoperative cognitive dysfunction (POCD) among anesthesiologists in China. METHODS: This cross-sectional study was conducted nationwide among Chinese anesthesiologists between December 2022 and January 2023. The demographic information and KAP scores of the respondents were collected using a web-based questionnaire. The mean KAP dimension scores ≥ 60% were considered good. RESULTS: This study enrolled 1032 anesthesiologists (51.2% male). The mean total scores of knowledge, positive attitude, and positive practice were 9.3 ± 1.2 (max 12), 34.8 ± 3.3 (max 40), and 30.6 ± 6.7 (max 40), respectively. The knowledge items with correctness scores < 60% were "the anesthetic drugs that tend to cause POCD" (23.3%) and "Treatment of POCD" (40.3%). Multivariable analysis showed that ≥ 40 years old, master's degree or above, intermediate professional title (i.e., attending physician), senior professional title (i.e., chief physician), and working in tertiary hospitals were independently associated with adequate knowledge. Multivariable analysis showed that the attitude scores, middle professional title, and ≥ 16 years of experience were independently associated with good practice. CONCLUSIONS: These results suggest that Chinese anesthesiologists have good knowledge, favorable attitudes, and good practice toward POCD. Still, some points remain to be improved (e.g., the drugs causing POCD and managing POCD) and should be emphasized in training and continuing education. TRIAL REGISTRATION: ChiCTR2200066749.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Complicações Cognitivas Pós-Operatórias , Humanos , Masculino , Adulto , Feminino , Estudos Transversais , Anestesiologistas , Inquéritos e Questionários , China/epidemiologia
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