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1.
BMC Biol ; 21(1): 205, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784185

RESUMO

BACKGROUND: After the eradication of smallpox in China in 1979, vaccination with the vaccinia virus (VACV) Tiantan strain for the general population was stopped in 1980. As the monkeypox virus (MPXV) is rapidly spreading in the world, we would like to investigate whether the individuals with historic VACV Tiantan strain vaccination, even after more than 40 years, could still provide ELISA reactivity and neutralizing protection; and whether the unvaccinated individuals have no antibody reactivity against MPXV at all. RESULTS: We established serologic ELISA to measure the serum anti-MPXV titer by using immunodominant MPXV surface proteins, A35R, B6R, A29L, and M1R. A small proportion of individuals (born before 1980) with historic VACV Tiantan strain vaccination exhibited serum ELISA cross-reactivity against these MPXV surface proteins. Consistently, these donors also showed ELISA seropositivity and serum neutralization against VACV Tiantan strain. However, surprisingly, some unvaccinated young adults (born after 1980) also showed potent serum ELISA activity against MPXV proteins, possibly due to their past infection by some self-limiting Orthopoxvirus (OPXV). CONCLUSIONS: We report the serum ELISA cross-reactivity against MPXV surface protein in a small proportion of individuals both with and without VACV Tiantan strain vaccination history. Combined with our serum neutralization assay against VACV and the recent literature about mice vaccinated with VACV Tiantan strain, our study confirmed the anti-MPXV cross-reactivity and cross-neutralization of smallpox vaccine using VACV Tiantan strain. Therefore, it is necessary to restart the smallpox vaccination program in high risk populations.


Assuntos
Reações Cruzadas , Monkeypox virus , Vacina Antivariólica , Vacinação , Animais , Humanos , Camundongos , Adulto Jovem , Formação de Anticorpos , População do Leste Asiático , Proteínas de Membrana , Varíola/prevenção & controle , Vaccinia virus , Vacina Antivariólica/imunologia , Vacina Antivariólica/uso terapêutico , China
2.
J Med Virol ; 95(2): e28440, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36573441

RESUMO

Emergence of various circulating SARS-CoV-2 variants of concern (VOCs) promotes the identification of pan-sarbecovirus vaccines and broadly neutralizing antibodies (bNAbs). Here, to characterize monoclonal antibodies cross-reactive against both SARS-CoV-1 and SARS-CoV-2 and to search the criterion for bNAbs against all emerging SARS-CoV-2, we isolated several SARS-CoV-1-cross-reactive monoclonal antibodies (mAbs) from a wildtype SARS-CoV-2 convalescent donor. These antibodies showed broad binding capacity and cross-neutralizing potency against various SARS-CoV-2 VOCs, including B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), and B.1.617.2 (Delta), but failed to efficiently neutralize Omicron variant and its sublineages. Structural analysis revealed how Omicron sublineages, but not other VOCs, efficiently evade an antibody family cross-reactive against SARS-CoV-1 through their escape mutations. Further evaluation of a series of SARS-CoV-1/2-cross-reactive bNAbs showed a negative correlation between the neutralizing activities against SARS-CoV-1 and SARS-CoV-2 Omicron variant. Together, these results suggest the necessity of using cross-neutralization against SARS-CoV-1 and SARS-CoV-2 Omicron as criteria for rational design and development of potent pan-sarbecovirus vaccines and bNAbs.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Vacinas , Humanos , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Monoclonais , Anticorpos Amplamente Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus
3.
J Sleep Res ; 32(2): e13808, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36529887

RESUMO

During pregnancy many women may experience negative emotions and sleep disturbances. This systematic review and meta-analysis was conducted to assess the efficacy of cognitive behavioural therapy for insomnia (CBT-I) or sleep disturbance in pregnant women. From the earliest available publications to 15 April 2022, seven electronic literature databases were searched: PubMed, Web of Science, Cochrane Library, Embase, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Database for Chinese Science and Technology Journal. Randomised controlled trials of CBT-I in pregnant women with insomnia or sleep disorders were included. The methodological bias of the included studies was assessed using the Cochrane risk of bias tool. The meta-analysis was performed using RevMan 5.4 software. Stata Statistical Software: Release 15 was used for sensitivity analysis and publication bias. We included eight randomised controlled trials involving 743 pregnant women. Meta-analysis showed that, compared with the control group, CBT-I significantly improved the Insomnia Severity Index (mean difference [MD] = -4.25, 95% confidence interval [CI, -6.32, -2.19], p < 0.001), The Pittsburgh Sleep Quality Index (MD = -3.30, 95% CI [-4.81, -1.79], p < 0.001), sleep onset latency (standardised mean difference [SMD] = -1.25, 95% CI [-2.01, -0.50], p = 0.001), anxiety (SMD = -0.99, 95% CI [-1.32, -0.67], p < 0.001), and depression (SMD = -0.40, 95% CI [-0.72, -0.07], p = 0.02). No significant differences were found in total sleep time (SMD = 0.31, 95% CI [-0.54, 1.17], p = 0.47) and sleep efficiency (SMD = 0.80, 95% CI [-0.53, 2.13], p = 0.24). CBT-I significantly improved pregnant women's sleep quality, insomnia severity, depression, and anxiety. This meta-analysis provides evidence that CBT-I is valid for insomnia or sleep disturbances during pregnancy.


Assuntos
Terapia Cognitivo-Comportamental , Gestantes , Transtornos do Sono-Vigília , Feminino , Humanos , Gravidez , Gestantes/psicologia , Duração do Sono , Distúrbios do Início e da Manutenção do Sono/psicologia , Distúrbios do Início e da Manutenção do Sono/terapia , Transtornos do Sono-Vigília/psicologia , Transtornos do Sono-Vigília/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
J Org Chem ; 88(21): 15151-15158, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37851408

RESUMO

NHC-boranes have been treated as a reliable source of boryl radicals. In this study, regioselective hydroborylation of ketene dithioacetals with NHC-borane was achieved under mild conditions via a visible-light-promoted radical chain process using thiophenol as a proton donor and hydrogen atom transfer. This protocol features a low-cost catalyst, good functional group tolerance, a relatively broad range of substrate scope, and good to excellent yields. Moreover, mechanism of this hydroborylation reaction was preliminarily studied.

5.
BMC Pulm Med ; 23(1): 385, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828534

RESUMO

BACKGROUND: Pulmonary rehabilitation training is of great significance for the prognosis of chronic obstructive pulmonary disease (COPD) patients. The purpose of this study was to investigate the therapeutic effect and pathway of a new sequential noninvasive positive pressure ventilation (NIPPV) + inspiratory muscle training (IMT) therapy. METHODS: A total of 100 COPD patients were enrolled and randomly divided into oxygen therapy (OT), NIPPV, IMT and sequential (NIPPV + IMT) group. Lung function, exercise endurance, quality of life, and dyspnea symptoms were examined and recorded. Then, reactive oxygen species (ROS), malonaldehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) levels were detected by enzyme-linked immunoassay, and suppressor of cytokine signaling 5 (SOCS5)/janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway expression changes were detected by quantitative real time-polymerase chain reaction (qRT-PCR) and western blot. A mouse model of COPD was then established to further verify the effects of SOCS5/JAK2/STAT3 pathways on lung function and oxidative stress. RESULTS: After 8 weeks of treatment, NIPPV, IMT or sequential (NIPPV + IMT) significantly improved exercise endurance, quality of life and dyspnea, reduced oxidative stress, promoted SOCS5 expression and inhibited the activation of JAK2/STAT3 pathway, and no significant effect was observed on lung function of COPD patients. Notably, sequential (NIPPV + IMT) showed better therapeutic outcomes than either IMT or NIPPV alone. Moreover, results at the animal level showed that overexpression of SOCS5 significantly reduced pulmonary inflammatory infiltration, pathological changes and oxidative stress levels in COPD mice, enhanced lung function, and inhibited the activation of JAK2/STAT3 pathway. CONCLUSION: Our results elucidated that sequential (NIPPV + IMT) significantly relieved COPD development by regulating SOCS5/JAK2/STAT3 signaling-mediated oxidative stress.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Fator de Transcrição STAT3 , Humanos , Animais , Camundongos , Fator de Transcrição STAT3/metabolismo , Janus Quinase 2/metabolismo , Qualidade de Vida , Dispneia/terapia , Estresse Oxidativo , Músculos/metabolismo , Respiração com Pressão Positiva , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Proteínas Supressoras da Sinalização de Citocina/farmacologia
6.
Org Biomol Chem ; 19(44): 9746-9751, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34730165

RESUMO

The iridium/f-diaphos L1, L5 or L12 catalyzed asymmetric hydrogenation of 2-imidazolyl aryl/alkyl ketones to afford two enantiomers of the desired chiral alcohols with high conversions (up to 99% yield) and moderate to excellent enantioselectivities (61% - >99% ee) was realized for the first time. This protocol could be easily conducted on a gram-scale with a TON of 9700.

7.
Mol Biol Rep ; 48(8): 1-15, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34333735

RESUMO

BACKGROUND: Malignant tumors have become the most dangerous disease in recent years. Chemotherapy is the most effective treatment for this disease; however, the problem of drug resistance has become even more common, which leads to the poor prognosis of patients suffering from cancers. Thus, necessary measures should be taken to address these problems at the earliest. Many studies have demonstrated that drug resistance is closely related to the abnormal expressions of long non-coding RNAs (lncRNAs). METHODS AND RESULTS: This review aimed to summarize the molecular mechanisms underlying the association of lncRNAs and the development of drug resistance and to find potential strategies for the clinical diagnosis and treatment of cancer drug resistance. Studies showed that lncRNAs can regulate the expression of genes through chromatin remodeling, transcriptional regulation, and post-transcriptional processing. Furthermore, lncRNAs have been reported to be closely related to the occurrence of malignant tumors. In summary, lncRNAs have gained attention in related fields during recent years. According to previous studies, lncRNAs have a vital role in several different types of cancers owing to their multiple mechanisms of action. Different mechanisms have different functions that could result in different consequences in the same disease. CONCLUSIONS: LncRNAs closely participated in cancer drug resistance by regulating miRNA, signaling pathways, proteins, cancer stem cells, pro- and ant-apoptosis, and autophagy. lncRNAs can be used as biomarkers of the possible treatment target in chemotherapy, which could provide solutions to the problem of drug resistance in chemotherapy in the future.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/genética , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , Resistência a Múltiplos Medicamentos/genética , Expressão Gênica/genética , Humanos , MicroRNAs/genética , Neoplasias/genética , RNA Longo não Codificante/metabolismo
8.
Appl Opt ; 60(34): 10727-10735, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200939

RESUMO

This paper proposes the automatic lens-splitting optimization algorithm to correct spherical aberration by the interaction between ZEMAX and MATLAB. This method tackled the problem that classic optimization cannot add the elements automatically. A high numerical aperture collimator is considered for the test sample, and the selection of four thickness constraints (minimum center and edge of glass and air thickness constraints) is discussed. To determine the feasibility and applicability of this method, more design systems (a retro-focus objective system and a telesystem) are tested. The simulated results under the feasible thickness constraints show that the automatic lens-splitting optimization algorithm generates reasonable and realizable solutions.

9.
Ecotoxicol Environ Saf ; 207: 111299, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32927158

RESUMO

The analogues of biphenol A (BPA), including bisphenol S (BPS) and bisphenol B (BPB), are commonly used to replace the application of BPA in containers and wrappers of daily life. However, their safeties are questioned due to their similar chemical structure and possible physiological effects as BPA. To investigate the neurotoxic effects of BPA, BPS, and BPB as well as their underlying mechanism, IMR-32 cell line from male and SK-N-SH cell line from female were exposed respectively to BPA, BPS and BPB with concentrations of 1 nM, 10 nM, 100 nM, 1 µM, 10 µM, and 100 µM for 24 h. Additionally, 24 h exposure of BPA combining epigallocatechin gallate (EGCG) (4 µM and 8 µM for IMR-32 and SK-N-SH respectively) were conducted. Results demonstrated that BPs exposure could promote reactive oxygen species production and increase level of malondialdehyde (MDA) while decrease levels of superoxide dismutase (SOD). Intensive study revealed that after exposure to BPA mitochondrial membrane potential (MMP) dropped down and the protein expression levels of Bak-1, Bax, cytochrome c and Caspase-3 were up-regulated but Bcl-2 were down-regulated significantly. Moreover, apoptosis rate was raised and cell activity declined remarkably in the neuroblastoma cells. All the effects induced by BPA could be alleviated by the adding of EGCG, which similar alleviations could be inferred in IMR-32 and SK-N-SH cells induced by BPS and BPB. Furthermore, BPS showed lower neurotoxic effects compared to BPA and BPB. Interestingly, the neurotoxic effects of BPA on IMR-32 cells were significantly higher than those on SK-N-SH cells. In conclusion, the results suggested that BPA, BPS and BPB could induce oxidative stress and apoptosis via mitochondrial pathway in the neuroblastoma cells and male is more susceptible to BPs than female.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/toxicidade , Sulfonas/toxicidade , Caspase 3/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Caracteres Sexuais
10.
Water Sci Technol ; 83(8): 1946-1957, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33905364

RESUMO

The effects of pure oxygen aeration on compositional characteristics of soluble microbial products (SMP) and extracellular polymeric substances (EPS) of the activated sludge acclimated in a sequential batch reactor (SBR) were explored in batch mode. The structure of the extracellular products would change with different aeration methods or aeration rates. The proportion of SMP of most oxygen aerated sludge was less than 10%, while that in air aerated sludge was as high as 30-40%. The proportion of TB-EPS decreased from 56.95% to 30.63%, and the proportion of LB-EPS increased obviously with the increase of oxygen aeration rate. The contents of the protein (PN) and the polysaccharide (PS) of extracellular products with oxygen aeration were significantly different, and the PN was much higher than PS (p < 0.05). The zeta potential of each component in activated sludge was negative, gradually decreasing with the progress of biological treatment. The fluorescence peaks in SMP, LB-EPS and TB-EPS with pure oxygen aeration were attributed to tryptophan PN-like and humic acid-like fractions. The results showed that the proportion of the components in the extracellular products could be regulated by adjusting the aeration rate and aeration mode, so as to optimize the treatment process of activated sludge.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Reatores Biológicos , Substâncias Húmicas , Oxigênio , Polissacarídeos
11.
J Tradit Chin Med ; 37(2): 201-6, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29960292

RESUMO

OBJECTIVE: To investigate the relationship between gene polymorphism of peroxisome proliferator- activated receptor (PPAR) and susceptibility to northwest dryness syndrome (NDS). METHODS: The polymorphisms of 11 PPARγ gene loci rs10510418, rs12633551, rs1373640, rs17036188, rs2921190, rs4135247, rs4135275, rs4135283, rs6768587, rs709156, and rs7615916 were detected in 249 patients with NDS and 260 patients with non-NDS (control group) by using Snapshot single-nucleotide polymorphism typing technology. RESULTS: All locus detections were in accordance with Hardy-Weinberg equilibrium test. Compared with the control group, rs2921190 genotype frequency showed statistical difference in the NDS group (P < 0.05). Two-two comparison result showed that CC genotype frequency in the NDS group was higher than that in the control group. CT and TT genotype distribution frequencies showed differences between the two groups. The rare allele frequency in the NDS group was lower than that of the control group (P < 0.01). Multi-factor logistic regression analysis showed that the age and genotype entered the regression equation. The subjects in the age bracket 30-55 and 45-45 were 1.796 and 1.561 times likely, respectively, than those in other age brackets to contract NDS,. The patients with CC genotype was only 0.524 times likely than those with CT/TT genotype to suffer from NDS. CONCLUSION: PPARγ gene rs2921190 polymorphism was correlated with the susceptibility to NDS.


Assuntos
Predisposição Genética para Doença/genética , PPAR gama/genética , Polimorfismo de Nucleotídeo Único , Xerostomia/genética , Adulto , China , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
12.
Environ Microbiol ; 17(10): 3898-913, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25912020

RESUMO

The underlying mechanisms of microbial community assembly in connective coastal environments are unclear. The coastal water area of northern Zhejiang, East China Sea, is a complex marine ecosystem with multiple environmental gradients, where the distributions and determinants of bacterioplankton communities remain unclear. We collected surface water samples from 95 sites across eight zones in this area for investigating bacterial community with 16S rRNA gene high-throughput sequencing. Bacterial alpha-diversity exhibits strong associations with water chemical parameters and latitude, with 75.5% of variation explained by suspended particle. The composition of dominant phyla can group the sampling sites into four bacterial provinces, and most key discriminant phyla and families/genera of each province strongly associate with specific environmental features, suggesting that local environmental conditions shape the biogeographic provincialism of bacterial taxa. At a broader and finer phylogenetic scale, bacterial beta-diversity is dominantly explained by the shared variation of environmental and spatial factors (63.3%); meanwhile, the environmental determinants of bacterial ß-diversity generally exhibit spatially structured patterns, suggesting that bacterial assembly in surface water is highly controlled by spatially structured environmental gradients in this area. This study provides evidence for the unique biogeographic pattern of bacterioplankton communities at an entire scale of this marine ecosystem.


Assuntos
Bactérias/classificação , Microbiota/genética , Plâncton/microbiologia , Água do Mar/microbiologia , Bactérias/genética , Sequência de Bases , China , DNA Bacteriano/genética , Ecossistema , Sequenciamento de Nucleotídeos em Larga Escala , Oceanos e Mares , Filogenia , Plâncton/classificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
ScientificWorldJournal ; 2014: 834357, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25301508

RESUMO

A simulated annealing (SA) based variable weighted forecast model is proposed to combine and weigh local chaotic model, artificial neural network (ANN), and partial least square support vector machine (PLS-SVM) to build a more accurate forecast model. The hybrid model was built and multistep ahead prediction ability was tested based on daily MSW generation data from Seattle, Washington, the United States. The hybrid forecast model was proved to produce more accurate and reliable results and to degrade less in longer predictions than three individual models. The average one-week step ahead prediction has been raised from 11.21% (chaotic model), 12.93% (ANN), and 12.94% (PLS-SVM) to 9.38%. Five-week average has been raised from 13.02% (chaotic model), 15.69% (ANN), and 15.92% (PLS-SVM) to 11.27%.


Assuntos
Previsões/métodos , Modelos Estatísticos , Resíduos Sólidos/estatística & dados numéricos , Humanos , Máquina de Vetores de Suporte
15.
Environ Eng Sci ; 31(8): 461-468, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25125942

RESUMO

In this study, a univariate local chaotic model is proposed to make one-step and multistep forecasts for daily municipal solid waste (MSW) generation in Seattle, Washington. For MSW generation prediction with long history data, this forecasting model was created based on a nonlinear dynamic method called phase-space reconstruction. Compared with other nonlinear predictive models, such as artificial neural network (ANN) and partial least square-support vector machine (PLS-SVM), and a commonly used linear seasonal autoregressive integrated moving average (sARIMA) model, this method has demonstrated better prediction accuracy from 1-step ahead prediction to 14-step ahead prediction assessed by both mean absolute percentage error (MAPE) and root mean square error (RMSE). Max error, MAPE, and RMSE show that chaotic models were more reliable than the other three models. As chaotic models do not involve random walk, their performance does not vary while ANN and PLS-SVM make different forecasts in each trial. Moreover, this chaotic model was less time consuming than ANN and PLS-SVM models.

16.
Sci Total Environ ; 919: 170711, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340817

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) exposure is related to the occurrence of cardiovascular diseases (CVDs). Endothelial dysfunction is considered an initial event of CVDs. To confirm the relationship of PAHs exposure with endothelial dysfunction, 8-week-old male SD rats and primary human umbilical vein endothelial cells (HUVECs) were co-treated with environmental doses of 16 priority-controlled PAHs for 90 d and 48 h, respectively. Results showed that 10× PAHs exposure remarkably raised tumor necrosis factor-α and malonaldehyde levels in rat serum (p < 0.05), but had no effects on interleukin-8 levels and superoxide dismutase activity. The expressions of SIRT1 in HUVECs and rat aorta were attenuated after PAHs treatment. Interestingly, PAHs exposure did not activate the expression of total endothelial nitric oxide synthase (eNOS), but 10× PAHs exposure significantly elevated the expression of phosphorylated eNOS (Ser1177) in HUVECs and repressed it in aortas, accompanied with raised nitrite level both in serum and HUVECs by 48.50-253.70 %. PAHs exposure also led to the augment of endothelin-1 (ET-1) levels by 19.76-38.54 %, angiotensin (Ang II) levels by 20.09-39.69 % in HUVECs, but had no effects on ET-1 and Ang II levels in serum. Additionally, PAHs exposure improved endocan levels both in HUVECs and serum by 305.05-620.48 % and stimulated the THP-1 cells adhered to HUVECs (p < 0.05). After PAHs treatment, the smooth muscle alignment was disordered and the vascular smooth muscle locally proliferated in rat aorta. Notably, the systolic blood pressure of rats exposed to 10× PAHs increased significantly compared with the control ones (131.28 ± 5.20 vs 116.75 ± 5.33 mmHg). In summary, environmental chronic PAHs exposure may result in endothelial dysfunction in SD rats and primary HUVECs. Our research can confirm the cardiovascular damage caused by chronic exposure to PAHs and provide ideas for the prevention or intervention of CVDs affected by environmental factors.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Masculino , Humanos , Ratos , Animais , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Ratos Sprague-Dawley , Células Endoteliais da Veia Umbilical Humana , Pressão Sanguínea , Óxido Nítrico/metabolismo
17.
Cartilage ; : 19476035231189841, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37646151

RESUMO

OBJECTIVE: Activation of sympathetic tone is important for cartilage degradation in osteoarthritis (OA). Recent studies reported that sympathetic signals can affect the mitochondrial function of target cells. It is unknown whether this effect exits in chondrocytes and affects chondrocyte catabolism. The contribution of mitochondrial dynamics in the activation of α2-adrenergic signal-mediated chondrocyte catabolism was investigated in this study. DESIGN: Primary chondrocytes were stimulated with norepinephrine (NE) alone, or pretreated with an α2-adrenergic receptor (Adra2) antagonist (yohimbine) and followed by stimulation with NE. Changes in chondrocyte metabolism and their mitochondrial dynamics were investigated. RESULTS: We demonstrated that NE stimulation induced increased gene and protein expressions of matrix metalloproteinase-3 and decreased level of aggrecan by chondrocytes. This was accompanied by upregulated mitochondriogenesis and the number of mitochondria, when compared with the vehicle-treated controls. Mitochondrial fusion and fission, and mitophagy also increased significantly in response to NE stimulation. Inhibition of Adra2 attenuated chondrocyte catabolism and mitochondrial dynamics induced by NE. CONCLUSIONS: The present findings indicate that upregulation of mitochondrial dynamics through mitochondriogenesis, fusion, fission, and mitophagy is responsible for activation of α2-adrenergic signal-mediated chondrocyte catabolism. The hypothesis that "α2-adrenergic signal activation promotes cartilage degeneration in temporomandibular joint osteoarthritis (TMJ-OA) by upregulating mitochondrial dynamics in chondrocytes" is validated. This represents a new regulatory mechanism in the chondrocytes of TMJ-OA that inhibits abnormal activation of mitochondrial fusion and fission is a potential regulator for improving mitochondrial function and inhibiting chondrocyte injury and contrives a potentially innovative therapeutic direction for the prevention of TMJ-OA.

18.
Environ Technol ; 44(27): 4210-4218, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35658802

RESUMO

This study aimed to investigate pollutant concentration and nitrogen interception characteristics of a forward osmosis (FO) process for concentrating black odorous water. The membrane cell was operated in active layer facing feed solution (AL-FS) mode with aquaporin (AQP) as the membrane material and NaCl solution as the draw solution (DS). The organic pollutants (COD), TP, NH+4-N, NO-3-N, TN, Fe and Mn in black odorous water were concentrated non-intermittently for 24 h, and their interception characteristics were investigated. The results showed that the average interception rates of COD, TP, NO- 3-N, TN, Fe and Mn were 97.2%, 98.0%, 58.7%, 54.3%, 61.8% and 60.0%, respectively, while the average interception rate of NH+4-N was only 1.27%-3.47%. To explore the characteristics of nitrogen interception, a comparison was conducted between AQP membrane and thin film composite (TFC) membrane. Because the surface electronegativity of AQP membrane was stronger than that of TFC, the effect of cation exchange on ammonia nitrogen interception was more serious with AQP membrane. With NaCl solution as DS, the reverse osmosis flux of Na+ was (0.53 ± 0.02 mol·m-2·h-1), which was significantly higher than that of Cl- (0.29 ± 0.03 mol·m-2·h-1) (P < 0.05). The interception effect of AQP membrane on TN was related to the proportion of NH+4-N in TN. The pretreatment of black odorous water by aeration could transform part of NH+4-N into NO-3-N, and reduce the negative effect of cation exchange effect on nitrogen interception. The TN interception rate increased from 54.3% to 66.1%.


Assuntos
Purificação da Água , Água , Cloreto de Sódio , Membranas Artificiais , Purificação da Água/métodos , Osmose , Cátions , Nitrogênio
19.
ACS Omega ; 8(27): 24247-24255, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37457452

RESUMO

Biomass is the ideal substitute for petrochemical resources because of its renewable and abundant sources. p-Toluenesulfonic acid (p-TsOH) can effectively separate lignin from biomass under mild conditions, so it is highly expected in biomass fractionation to improve the utilization efficiency. In this study, we investigated the effect of p-TsOH differentiated fractionation of poplar sawdust, eucalyptus sawdust, and rice straw below 100 °C. According to the experimental results, upon pretreatment by p-TsOH of the three kinds of raw biomass, most of the lignin and hemicellulose of poplar sawdust and eucalyptus sawdust were removed, whereas the cellulose was retained, but most of the hemicellulose and cellulose of rice straw were kept, whereas the lignin was removed at similar conditions. The structures and compositions of pretreatment residues, lignin, and hemicellulose extracted from raw biomass were characterized by XRD, FTIR, HSQC-NMR, XPS, and SEM. The differentiated fractionation mechanism of biomass was analyzed. A better recognition and understanding of the factors affecting biomatrix opening and fractionation will allow for the identification of new pretreatment strategies that improve biomass utilization and permit the rational enzymatic hydrolysis of cellulose.

20.
Front Bioeng Biotechnol ; 11: 1138601, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36949886

RESUMO

Introduction: Sensory nerves and vessels are critical for skeletal development and regeneration, but crosstalk between neurovascular network and mineralization are not clear. The aim of this study was to explore neurovascular changes and identify bioactive regulators during in situ osteogenesis. Method: In situ osteogenesis model was performed in male rats following Achilles tenotomy. At 3, 6 and 9 weeks after surgery, mineralization, blood vessels, sensory innervation, and bioactive regulators expression were evaluated via micro-computed tomography, immunofluorescent staining, histology and reverse transcriptase-polymerase chain reaction analyses. Result: In the process of in situ osteogenesis, the mineral density increased with time, and the locations of minerals, nerves and blood vessels were highly correlated at each time point. The highest density of sensory nerve was observed in the experimental group at the 3rd week, and then gradually decreased with time, but still higher than that in the sham control group. Among many regulatory factors, semaphorin 3A (Sema3A) was highly expressed in experimental model and its expression was temporally sequential and spatially correlated sensory nerve. Conclusion: The present study showes that during in situ osteogenesis, innervation and angiogenesis are highly correlated, and Sema3A is associated with the position and expression of the sensory nerve.

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