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1.
Phys Rev Lett ; 132(11): 118301, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563944

RESUMO

We investigate collective dynamics in a binary mixture of programmable robots in experiments and simulations. While robots of the same species align their motion direction, interaction between species is distinctly nonreciprocal: species A aligns with B and species B antialigns with A. This nonreciprocal interaction gives rise to the emergence of collective chiral motion that can be stabilized by limiting the robot angular speed to be below a threshold. Within the chiral phase, increasing the robot density or extending the range of local repulsive interactions can drive the system through an absorbing-active transition. At the transition point, the robots exhibit a remarkable capacity for self-organization, forming disordered hyperuniform states.

2.
BMC Public Health ; 22(1): 1493, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931976

RESUMO

BACKGROUND: With the acceleration of industrialization and population aging, low back pain (LBP) has become the leading cause of life loss years caused by disability. Thus, it places a huge economic burden on society and is a global public health problem that needs urgent solution. This study aimed to conduct an epidemiological investigation and research on a large sample of workers in key industries in different regions of China, determine the incidence and distribution characteristics of LBP, explore the epidemic law, and provide a reference basis for alleviating global public health problems caused by LBP. METHODS: We adopted a modified epidemiological cross-sectional survey method and a stratified cluster sampling method. All on-duty workers who fulfill the inclusion criteria are taken as the research participants from the representative enterprises in key industries across seven regions: north, east, central, south, southwest, northwest, and northeast China. The Chinese version of the musculoskeletal disease questionnaire, modified by a standardized Nordic questionnaire, was used to collect information, and 57,501 valid questionnaires were received. Descriptive statistics were used, and multivariate logistic regression analysis (p < 0.05) was performed to explore the association between musculoskeletal disorders and potential risk factors. RESULTS: LBP annual incidence among workers in China's key industries is 16.4%. There was a significant difference in LBP incidence among occupational groups across different industries (p < 0.05). The multivariate regression model showed the following as risk factors for LBP: frequent repetitive movements with the trunk, working in the same positions at a high pace, trunk position, frequently turning around with your trunk, often working overtime, lifting heavy loads (i.e., more than 20 kg), education level, staff shortage, working age (years), cigarette smoking, use of vibration tools at work, body mass index, lifting heavy loads (i.e., more than 5 kg), and age (years). Physical exercise, often standing at work, and absolute resting time were protective factors. CONCLUSION: LBP incidence among key industries and workers in China is high. Thus, it is urgent to take relevant measures according to the individual, occupational, and psychosocial factors of LBP to reduce the adverse impact of LBP on workers' health.


Assuntos
Dor Lombar , Doenças Profissionais , China/epidemiologia , Estudos Transversais , Humanos , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Doenças Profissionais/etiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários
3.
BMC Musculoskelet Disord ; 23(1): 952, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329459

RESUMO

BACKGROUND: Changes in modern industrial production practices can easily lead to shoulder work-related musculoskeletal disorders (WMSD). The current reports on shoulder WMSD are limited to some industries are less well studied, and the sample size is usually small. This study aimed to describe the prevalence and severity of shoulder WMSD in a large sample of Chinese workers from 15 industries, analyze the possible correlations with sociodemographic and work-related variables, and compare the differences between industries. METHODS: A cross-sectional study was conducted among a sample of 55,749 participants from 252 enterprises in 15 industries throughout China. A Chinese version of the musculoskeletal disease questionnaire was used to collect the demographic factors, shoulder symptoms in past 12 months, and work-related factors including posture-related factors, repetition, vibration, work organization, job control, and environmental factors as independent variables. Descriptive statistics were used, and the binary logistic regression analysis was performed to explore the association between shoulder WMSD and potential demographic and work-related factors. RESULTS: Nearly 35.5% of participants reported shoulder pain and discomfort in the previous 12 months. Biopharmaceutical manufacturing (56.2%), medical services (54.4%), and aviation services (50.1%) were the three industries with the highest prevalence of shoulder WMSD. The pain score of aviation services workers was the highest. The related factors for shoulder WMSD varied among the different industries. CONCLUSION: Our study found a relatively high prevalence of shoulder WMSD in China. There were large differences in the prevalence of shoulder WMSD among industries, and the related factors were particular to each industry. Such information is useful to help occupational health practitioners and policymakers conduct preventive programs to reduce shoulder disorders in these working populations.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Ombro , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Musculoesqueléticas/diagnóstico , Doenças Musculoesqueléticas/epidemiologia , Prevalência , Inquéritos e Questionários , China/epidemiologia , Fatores de Risco
4.
Org Biomol Chem ; 19(47): 10455-10459, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34817493

RESUMO

A novel and simple one-pot stepwise method to synthesize benzoxaboroles was demonstrated. This step-by-step synthetic method includes photocatalytic boronization with phenothiazine as a photocatalyst and sequential water-induced reduction in the presence of bis(pinacolato)diboron. A series of o-bromobenzaldehydes were well-tolerated under the standard conditions. In addition, this method has been successfully applied in the synthesis of the anti-tuberculosis candidate drug GSK 3036656 and anti-fungal drug tavaborole.

5.
J Nat Prod ; 82(9): 2419-2429, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31503490

RESUMO

Eight new limonoids, toononoids A-H (1-8), eight new B-seco-29-norlimonoids, toonanoronoids A-H (9-16), and seven known analogues were obtained from the EtOAc extract of the twigs and leaves of Toona ciliata. Compounds 2, 4, 8, and 16 are rare lactam-bearing limonoids. Compounds 1, 14, and 15 possess an unusual γ-methoxybutenolide moiety at C-17, while compounds 9, 10, and 15 have a rare 3ß-hydroxy group. Their 2D structure and relative configurations were identified using spectroscopic data. The absolute configurations of 1, 9, 14, and 15 were established via X-ray diffraction crystallography or comparison of experimental and calculated ECD data. The cytotoxicity of the compounds was assessed toward five human tumor cell lines, and their anti-inflammatory activity was assessed based on NO production using LPS-stimulated RAW264.7 macrophages. Compounds 11 and 12 exerted inhibition toward two tumor cell lines (MCF-7, SW-480) with IC50 values between 2.1 and 3.7 µM, while 18-22 inhibited the proliferation of HL-60, MCF-7, and SW-480 cells (IC50 0.6-4.0 µM). Only compound 4 exhibited weak anti-inflammatory activity with an IC50 value of 28.3 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Folhas de Planta/química , Caules de Planta/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Células HL-60 , Humanos , Limoninas/química , Limoninas/isolamento & purificação
6.
Proc Natl Acad Sci U S A ; 112(27): 8284-9, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26100870

RESUMO

Selective inhibition of the intrinsic coagulation pathway is a promising strategy for developing safer anticoagulants that do not cause serious bleeding. Intrinsic tenase, the final and rate-limiting enzyme complex in the intrinsic coagulation pathway, is an attractive but less explored target for anticoagulants due to the lack of a pure selective inhibitor. Fucosylated glycosaminoglycan (FG), which has a distinct but complicated and ill-defined structure, is a potent natural anticoagulant with nonselective and adverse activities. Herein we present a range of oligosaccharides prepared via the deacetylation-deaminative cleavage of FG. Analysis of these purified oligosaccharides reveals the precise structure of FG. Among these fragments, nonasaccharide is the minimum fragment that retains the potent selective inhibition of the intrinsic tenase while avoiding the adverse effects of native FG. In vivo, the nonasaccharide shows 97% inhibition of venous thrombus at a dose of 10 mg/kg in rats and has no obvious bleeding risk. This nonasaccharide may therefore serve as a novel promising anticoagulant.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Oligossacarídeos/farmacologia , Animais , Anticoagulantes/química , Anticoagulantes/metabolismo , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Sequência de Carboidratos , Cisteína Endopeptidases/metabolismo , Relação Dose-Resposta a Droga , Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Fucose/metabolismo , Glicosaminoglicanos/química , Glicosaminoglicanos/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Dados de Sequência Molecular , Estrutura Molecular , Proteínas de Neoplasias/metabolismo , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray , Trombose Venosa/prevenção & controle
7.
Int Heart J ; 57(4): 473-6, 2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27396558

RESUMO

To summarize the therapeutic effects of modified double root translocation (MDRT) in the management of congenital heart disease-transposition of great arteries (TGA) with ventricular septum defect (VSD) and left ventricular outflow tract obstruction (LVOTO). From May 2013 to March 2015, we treated 6 patients (4 males, 2 females, aged from 1 year and 8 months old to 5 years old) with complete transposition of great arteries with left ventricular outflow tract obstruction, SaO2 54 ± 7.3%; the outflow velocity of the left ventricular or pulmonary valve measured by Doppler was 4.46 ± 0.15 m/s, and the Nakata index was 217 ± 32 cm(2)/m(2). We carried out a double root translocation operation on these 6 patients.One patient developed low cardiac output syndrome 4 hours after the operation. Extracorporeal membrane oxygenation (ECMO) was performed, but the patient died of multiple organ failure. The other 5 patients all recovered and were discharged from the hospital. During the 3-month to 2-year follow-up period, these 5 patients all demonstrated NYHA Class I or NYHA Class II LVEF (65 ± 2.7) %; 4 had mild pulmonary regurgitation, 1 moderate pulmonary regurgitation; 3 no aortic regurgitation, and 2 micro aortic regurgitation, SaO2 99 ± 0.4%.Modified double root translocation is an effective treatment method in the management of complete transposition of great arteries with left ventricular outflow tract obstruction.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Comunicação Interventricular/cirurgia , Transposição dos Grandes Vasos/cirurgia , Obstrução do Fluxo Ventricular Externo/cirurgia , Insuficiência da Valva Aórtica , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Pré-Escolar , Feminino , Seguimentos , Comunicação Interventricular/diagnóstico por imagem , Comunicação Interventricular/mortalidade , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Risco , Transposição dos Grandes Vasos/diagnóstico por imagem , Transposição dos Grandes Vasos/mortalidade , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/mortalidade
8.
Molecules ; 21(9)2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27571056

RESUMO

Three new triterpenoid alkaloids, namely buxmicrophyllines P-R (1-3), were isolated from the twigs and leaves of Buxus microphylla. Their structures were elucidated on the basis of NMR and MS spectroscopic analyses. Structurally, compounds 1-3 belong to the 9,10-cycloartane type alkaloids. In addition, compound 3 exhibited moderate cytotoxic activities in vitro against HL-60, SMMC-7221, A-549, MCF-7, and SW480 cell lines (with IC50 values ranging from 4.51 to 15.58 µM).


Assuntos
Alcaloides , Antineoplásicos Fitogênicos , Buxus/química , Citotoxinas , Triterpenos , Células A549 , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Células HL-60 , Humanos , Células MCF-7 , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
9.
Planta Med ; 81(4): 327-32, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25760384

RESUMO

Five new cucurbitacins, kuguacins II-VI (1-5), along with five known analogues (6-10), were obtained from the fruit of Momordica charantia. Structures of the new compounds were elucidated as 5ß,19-epoxycucurbit-23-en-7-on-3ß,25-diol (1), 5ß,19-epoxycucurbit-7,23-dion-3ß,25-diol (2), 5ß,19-epoxycucurbit-6-en-19,23-dion-3ß,25-diol (3), 5ß,19-epoxy-23,24,25,26,27-pentanorcucurbit-6-en-7,19-dion-3ß,22-diol (4), and cucurbit-5-en-7,23-dion-3ß,19,25-triol (5) by extensive spectroscopic and single-crystal X-ray diffraction analyses. Some cucurbitane compounds from this species were screened for their potential antidiabetic properties in terms of antigluconeogenic activity. As a result, compounds 1, 10, 11, and 12 (at 25-100 µM) showed concentration-dependent inhibition on glucose production from liver cells. In addition, compounds 11 and 12 (at 100 µM) showed around 20-30 % inhibition on PEPCK activity.


Assuntos
Cucurbitacinas/farmacologia , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Fígado/efeitos dos fármacos , Momordica charantia/química , Extratos Vegetais/farmacologia , Cucurbitacinas/isolamento & purificação , Frutas/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Hipoglicemiantes/isolamento & purificação , Fígado/metabolismo , Estrutura Molecular , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Extratos Vegetais/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Difração de Raios X
10.
Chem Biodivers ; 12(7): 1040-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26172324

RESUMO

Four new limonoids, azadiraindins A-D (1-4, resp.), together with seven known analogs, were isolated from the MeOH extract of Azadirachta indica. The structures of 1-4 were elucidated by NMR and MS spectroscopic analyses, and the relative configuration of 1 was determined by single-crystal X-ray crystallography. The compounds isolated in comparatively large amount were evaluated for their antifeedant activities against Plutella xylostella; the antifeedant rate of 10 was 90.6% and the corrected mortality of 8 was 79.2%.


Assuntos
Azadirachta/química , Comportamento Alimentar/efeitos dos fármacos , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Limoninas/farmacologia , Animais , Cristalografia por Raios X , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Limoninas/química , Limoninas/isolamento & purificação , Modelos Moleculares , Conformação Molecular
11.
J Asian Nat Prod Res ; 17(1): 14-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25289883

RESUMO

Three new limonoids, azadiraindins E-G (1-3, respectively), together with six known analogs, were isolated from the fresh fruit coats of Azadirachta indica. The structures of these compounds were elucidated by spectroscopic methods (IR, MS, HR-ESI-MS, 1D NMR, and 2D NMR).


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Azadirachta/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Limoninas/isolamento & purificação , Antineoplásicos Fitogênicos/química , Medicamentos de Ervas Chinesas/química , Frutas/química , Limoninas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1719-23, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26601397

RESUMO

In coal-fired plants, Unburned carbon (UC) in fly ash is the major determinant of combustion efficiency in coal-fired boiler. The balance between unburned carbon and NO(x) emissions stresses the need for rapid and accurate methods for the measurement of unburned carbon. Laser-induced breakdown spectroscopy (LIBS) is employed to measure the unburned carbon content in fly ash. In this case, it is found that the C line interference with Fe line at about 248 nm. The interference leads to C could not be quantified independently from Fe. A correction approach for extracting C integrated intensity from the overlapping peak is proposed. The Fe 248.33 nm, Fe 254.60 nm and Fe 272.36 nm lines are used to correct the Fe 247.98 nm line which interference with C 247.86 nm, respectively. Then, the corrected C integrated intensity is compared with the uncorrected C integrated intensity for constructing calibration curves of unburned carbon, and also for the precision and accuracy of repeat measurements. The analysis results show that the regression coefficients of the calibration curves and the precision and accuracy of repeat measurements are improved by correcting C-Fe interference, especially for the fly ash samples with low level unburned carbon content. However, the choice of the Fe line need to avoid a over-correction for C line. Obviously, Fe 254.60 nm is the best

13.
Mycotoxin Res ; 40(1): 175-186, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224413

RESUMO

Aflatoxin B1 is a highly carcinogenic and teratogenic substance mainly produced by toxin-producing strains such as Aspergillus flavus and Aspergillus parasitic. The efficient decomposition of aflatoxin is an important means to reduce its harm to humans and livestock. In this study, Trametes versicolor aflatoxin B1-degrading enzyme (TV-AFB1D) was recombinantly expressed in Bacillus subtilis (B. subtilis) 168. MMT-CTAB-AFB1D complex was prepared by the immobilization of TV-AFB1D and montmorillonite (MMT) by cross-linking glutaraldehyde. The results indicated that TV-AFB1D could recombinantly express in engineered B. subtilis 168 with a size of approximately 77 kDa. The immobilization efficiency of MMT-CTAB-AFB1D reached 98.63% when the concentration of glutaraldehyde was 5% (v/v). The relative activity of TV-AFB1D decreased to 72.36% after reusing for 10 times. The content of AFB1 in MMT-CTAB-AFB1D-AFB1 decreased to 1.1 µg/g from the initial 5.6 µg/g after incubation at 50 °C for 6 h. The amount of 80.4% AFB1 in the MMT-CTAB-AFB1D-AFB1 complex was degraded by in situ catalytic degradation. Thus, the strategy of combining adsorption and in situ degradation could effectively reduce the content of AFB1 residue in the MMT-CTAB-AFB1D complex.


Assuntos
Aflatoxina B1 , Polyporaceae , Trametes , Humanos , Aflatoxina B1/metabolismo , Trametes/metabolismo , Bentonita , Cetrimônio , Glutaral
14.
Int J Occup Saf Ergon ; 30(1): 56-63, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36516459

RESUMO

Objectives. This study aimed to identify the prevalence of multi-site work-related musculoskeletal disorders (WMSDs) in Chinese footwear industry workers from 2018 to 2020 and explore the possible influencing factors of WMSDs. Methods. 7106 subjects from 26 large shoe factories in China were investigated using the epidemiological cross-sectional survey method by using the Nordic musculoskeletal questionnaire (NMQ). Results. The total prevalence of WMSDs in the study subjects was 36.8% (2616/7106). Among them, the prevalence of multi-site WMSDs was 26.1% (1858/7106). The proportion of multi-site WMSDs involving two sites was the largest (31.38%). In addition, the results showed that the risk factors of multi-site WMSDs were gender, marital status, long current job experience, poor health, poor working posture, etc. Conclusions. The prevalence of WMSDs was high in the Chinese footwear industry. Based on the results, therefore, it seems necessary to improve work posture, work organization and workenvironment to prevent WMSDs.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Estudos Transversais , Doenças Profissionais/epidemiologia , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Fatores de Risco , Inquéritos e Questionários , China/epidemiologia , Prevalência
15.
J Occup Health ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955204

RESUMO

OBJECTIVE: Although studies have shown that Work-related Musculoskeletal Disorders (WMSDs) are common and continue to be a main source of disability and work time loss, there are few reports on elbow WMSDs. The aim of this study was to explore the prevalence and associated factors of elbow WMSDs. METHODS: The valid questionnaires of 57501 workers from 15 different industries nationwide were collected and the Chi-square test and logistic-regression-analysis were applied to reveal the prevalence and risk factors of elbow. RESULTS: The findings indicated that prevalence of elbow WMSDs among workers was 7.3%. The prevalence of elbow WMSDs in toy manufacturing was 21.3%, which significantly higher than that in other industries (P<0.05). Logistic regression analysis showed that aged 40 and above, married, very poor health, left-handed, lifting weights (more than 20 kg each time) , work requiring upper limb or hand force, work in an uncomfortable position, repetitive operations within one minute, using vibrating tools, work involves cold, cool winds or temperature changes, work being completed in the same workshop, work being done outdoors, frequent deal with customers , two shifts, often work overtime, staff shortage, often work for colleagues were the risk factors of elbow WMSDs.The higer education level and monthly income, and enough rest time were the protective factors of elbow WMSDs. CONCLUSION: The toy manufacturing is a high-risk industry for elbow WMSDs. The publicity and education of ergonomics knowledge should be strengthened, and the workers' ergonomics awareness should be improved to reduce the impact of WMSDs.

16.
Epigenomics ; 15(20): 1069-1084, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37968910

RESUMO

Adaptation to variations in oxygen concentration is a conserved mechanism in all metazoans. Extensive studies have been focused on the roles of hypoxia-inducible factors (HIFs) in response to hypoxia. However, HIF1α is not conserved in all animals, and HIF2α and HIF3α are only observed in vertebrates. In this review, we discuss mechanisms enabling three cross-species to adapt to hypoxic conditions. Using transcriptomic data of hypoxia-induced genes from distantly related metazoans, we analyzed the enrichment and conservation of mRNA determinants such as transcript, CDS, 5'UTR and 3'UTR size. We found that long genes are enriched in hypoxia-induced transcripts and might be translated in a 3'UTR-dependent manner. We hope our work can provide a new direction on investigating alternative mechanisms for mRNA translation under hypoxia.


Many studies have focused on a group of proteins called hypoxia-inducible factors (HIFs) that help animals adapt to different oxygen concentrations, but not all animals have the same HIF proteins. This means that some genes involved in oxygen adaptation work differently in different animals. In this review, we look at three different species and how they adapt to low oxygen levels, with a special focus on how genes are used to make proteins. We used information from these species to see if certain features of genes (like their size) are important for adaptation. We found that in response to low oxygen, longer genes become more active and may use a specific part of the gene to make proteins. However, some common features thought to be important for gene activity in low oxygen were not found to be significant. This research gives us new directions to explore how genes make proteins in low-oxygen conditions, which is important for understanding how animals survive in changing environments.


Assuntos
Hipóxia , Biossíntese de Proteínas , Animais , Regiões 3' não Traduzidas , Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia
17.
J Orthop Surg Res ; 18(1): 380, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221568

RESUMO

OBJECTIVE: The implantation of PMMA bone cement results in an immune response and the release of PMMA bone cement particles causes an inflammatory cascade. Our study discovered that ES-PMMA bone cement can induce M2 polarization of macrophages, which has an anti-inflammatory immunomodulatory effect. We also delved into the molecular mechanisms that underlie this process. METHODS: In this study, we designed and prepared samples of bone cement. These included PMMA bone cement samples and ES-PMMA bone cement samples, which were implanted into the back muscles of rats. At 3, 7, and 14 days after the operation, we removed the bone cement and a small amount of surrounding tissue. We then performed immunohistochemistry and immunofluorescence to observe the polarization of macrophages and the expression of related inflammatory factors in the surrounding tissues. The RAW264.7 cells were exposed to lipopolysaccharide (LPS) for 24 h to establish the macrophage inflammation model. Then, each group was treated with enoxaparin sodium medium, PMMA bone cement extract medium, and ES-PMMA bone cement extract medium, respectively, and cultured for another 24 h. We collected cells from each group and used flow cytometry to detect the expressions of CD86 and CD206 in macrophages. Additionally, we performed RT-qPCR to determine the mRNA levels of three markers of M1 macrophages (TNF-α, IL-6, iNOS) and two M2 macrophage markers (Arg-1, IL-10). Furthermore, we analyzed the expression of TLR4, p-NF-κB p65, and NF-κB p65 through Western blotting. RESULTS: The immunofluorescence results indicate that the ES-PMMA group exhibited an upregulation of CD206, an M2 marker, and a downregulation of CD86, an M1 marker, in comparison to the PMMA group. Additionally, the immunohistochemistry results revealed that the levels of IL-6 and TNF-α expression were lower in the ES-PMMA group than in the PMMA group, while the expression level of IL-10 was higher in the ES-PMMA group. Flow cytometry and RT-qPCR analyses revealed that the expression of M1-type macrophage marker CD86 was significantly elevated in the LPS group compared to the NC group. Additionally, M1-type macrophage-related cytokines TNF-α, IL-6, and iNOS were also found to be increased. However, in the LPS + ES group, the expression levels of CD86, TNF-α, IL-6, and iNOS were decreased, while the expression of M2-type macrophage markers CD206 and M2-type macrophage-related cytokines (IL-10, Arg-1) were increased compared to the LPS group. In comparison to the LPS + PMMA group, the LPS + ES-PMMA group demonstrated a down-regulation of CD86, TNF-α, IL-6, and iNOS expression levels, while increasing the expression levels of CD206, IL-10, and Arg-1. Western blotting results revealed a significant decrease in TLR4/GAPDH and p-NF-κB p65/NF-κB p65 in the LPS + ES group when compared to the LPS group. Additionally, the LPS + ES-PMMA group exhibited a decrease in TLR4/GAPDH and p-NF-κB p65/NF-κB p65 levels when compared to the LPS + PMMA group. CONCLUSION: ES-PMMA bone cement is more effective than PMMA bone cement in down-regulating the expression of the TLR4/NF-κB signaling pathway. Additionally, it induces macrophages to polarize towards the M2 phenotype, making it a crucial player in anti-inflammatory immune regulation.


Assuntos
Cimentos Ósseos , Interleucina-10 , Animais , Ratos , NF-kappa B , Interleucina-6 , Lipopolissacarídeos , Polimetil Metacrilato , Receptor 4 Toll-Like , Fator de Necrose Tumoral alfa , Macrófagos , Anti-Inflamatórios , Citocinas , Imunidade
18.
Adv Mater ; 35(16): e2211611, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36739495

RESUMO

Group IIIA-VA metal sulfides (GMSs) have attracted increasing attention because of their unique Na-storage mechanisms through combined conversion and alloying reactions, thus delivering large theoretical capacities and low working potentials. However, Na+ diffusion within GMSs anodes leads to severe volume change, generally representing a fundamental limitation to rate capability and cycling stability. Here, monodispersed In6 S7 /nitrogen and sulfur co-doped carbon hollow microspindles (In6 S7 /NSC HMS) are produced by morphology-preserved thermal sulfurization of spindle-like and porous indium-based metal organic frameworks. The resulting In6 S7 /NSC HMS anode exhibits theoretical-value-close specific capacity (546.2 mAh g-1 at 0.1 A g-1 ), ultrahigh rate capability (267.5 mAh g-1 at 30.0 A g-1 ), high initial coulombic efficiency (≈93.5%), and ≈92.6% capacity retention after 4000 cycles. This kinetically favored In6 S7 /NSC HMS anode fills up the kinetics gap with a capacitive porous carbon cathode, enabling a sodium-ion capacitor to deliver an ultrahigh energy density of 136.3 Wh kg-1 and a maximum power density of 47.5 kW kg-1 . The in situ/ex situ analytical techniques and theoretical calculation both show that the robust and fast Na+ charge storage of In6 S7 /NSC HMS arises from the multi-electron redox mechanism, buffered volume expansion, negligible morphological change, and surface-controlled solid-state Na+ transport.

19.
Biotechnol Biofuels Bioprod ; 16(1): 66, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046321

RESUMO

BACKGROUND: The thermotolerant yeast is beneficial in terms of efficiency improvement of processes and reduction of costs, while Saccharomyces cerevisiae does not efficiently grow and ferment at high-temperature conditions. The sterol composition alteration from ergosterol to fecosterol in the cell membrane of S. cerevisiae affects the thermotolerant capability. RESULTS: In this study, S. cerevisiae ERG5, ERG4, and ERG3 were knocked out using the CRISPR-Cas9 approach to impact the gene expression involved in ergosterol synthesis. The highest thermotolerant strain was S. cerevisiae ERG5ΔERG4ΔERG3Δ, which produced 22.1 g/L ethanol at 37 °C using the initial glucose concentration of 50 g/L with an increase by 9.4% compared with the wild type (20.2 g/L). The ethanol concentration of 9.4 g/L was produced at 42 ℃, which was 2.85-fold of the wild-type strain (3.3 g/L). The molecular mechanism of engineered S. cerevisiae at the RNA level was analyzed using the transcriptomics method. The simultaneous deletion of S. cerevisiae ERG5, ERG4, and ERG3 caused 278 up-regulated genes and 1892 down-regulated genes in comparison with the wild-type strain. KEGG pathway analysis indicated that the up-regulated genes relevant to ergosterol metabolism were ERG1, ERG11, and ERG5, while the down-regulated genes were ERG9 and ERG26. S. cerevisiae ERG5ΔERG4ΔERG3Δ produced 41.6 g/L of ethanol at 37 °C with 107.7 g/L of corn liquefied glucose as carbon source. CONCLUSION: Simultaneous deletion of ERG5, ERG4, and ERG3 resulted in the thermotolerance improvement of S. cerevisiae ERG5ΔERG4ΔERG3Δ with cell viability improvement by 1.19-fold at 42 °C via modification of steroid metabolic pathway. S. cerevisiae ERG5ΔERG4ΔERG3Δ could effectively produce ethanol at 37 °C using corn liquefied glucose as carbon source. Therefore, S. cerevisiae ERG5ΔERG4ΔERG3Δ had potential in ethanol production at a large scale under supra-optimal temperature.

20.
ACS Nano ; 17(23): 24290-24298, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084421

RESUMO

All-solid-state batteries (ASSBs) with a Li metal anode are expected to be one of the most promising energy storage systems to achieve high energy density. However, the interfacial instability between the Li metal anode and solid-state electrolyte (SSE) limits the rate capability and cycling stability of ASSBs. The main issue is the formation of voids at the Li/SSE interface during Li stripping due to the slow diffusion of Li within the bulk Li metal, then increasing internal cell resistance and inducing the formation of lithium dendrites. To address these issues, a composite Li anode (LAO) composed by Li-Ag alloy and Li2O is constructed by mixing the stoichiometric metal Li and Ag2O directly. LAO anode is capable of improving bulk Li diffusion kinetics and inhibiting the formation of interfacial voids effectively, achieving a high critical current density over 1.5 mA cm-2 and long stable cycling over 1000 h at 1 mA cm-2. The ASSBs, employing LAO as the anode, Li6PS5Cl as the SSE, and LiCoO2 as the cathode, exhibit superior rate capability and stable cycling over 4000 cycles at 5 C. Moreover, ASSBs can operate stably with a high LiCoO2 loading of 17.8 mg cm-2 for more than 100 cycles at 0.2 C.

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