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1.
Carbohydr Polym ; 280: 119031, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35027133

RESUMO

We selected eight kinds of chitosan fibers to characterize and analyze their composition, surface morphology, and mechanical properties. Crucially, we investigated their antibacterial activity against Escherichia coli, Staphylococcus aureus and Candida albicans and the dependence on the molecular weight (Mw) and the degree of deacetylation (DD). On that basis, the relationship between antibacterial activity and Mw and DD can be established. Finally, the antibacterial mechanism of chitosan fiber was obtained. The results show that the inhibition rate of samples I, K, L, and M against Staphylococcus aureus first increased and then decreased with the increase of Mw, and their bactericidal activity against Escherichia coli decreased with the increase of Mw when the DD was similar. This study provides an effective strategy for characterizing the chitosan fiber and the resultant relationship between antibacterial property and structural parameters that may benefit the enhancement of antibacterial activity and application in antibacterial textiles.

2.
Mitochondrial DNA B Resour ; 7(1): 164-166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35005234

RESUMO

Prunus clarofolia (Schneid.) Yu et Li is a very attractive wild flowering cherry endemic to China. In this study, the complete chloroplast genome of P. clarofolia was assembled. The total length of the chloroplast genome was 157,899 bp, containing a pair of inverted repeat regions of 26,393 bp each, separated by a small single-copy region of 19,142 bp, and a large single-copy region of 85,971 bp. The overall GC content of the chloroplast genome was 36.71%. The genome contained 131 genes, including 85 protein-coding genes, 37 tRNA genes, eight rRNA genes, and one pseudogene. Phylogenetic analysis revealed that P. clarofolia and P. pseudocerasus showed the closest relationship.

3.
Sci Rep ; 12(1): 412, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013490

RESUMO

The endometrium plays a critical role in embryo implantation and pregnancy, and a thin uterus is recognized as a key factor in embryo implantation failure. Umbilical cord mesenchymal stem cells (UC-MSCs) have attracted interest for the repair of intrauterine adhesions. The current study investigated the repair of thin endometrium in rats using the UC-MSCs and the mechanisms involved. Rats were injected with 95% ethanol to establish a model of thin endometrium. The rats were randomly divided into normal, sham, model, and UC-MSCs groups. Endometrial morphological alterations were observed by hematoxylin-eosin staining and Masson staining, and functional restoration was assessed by testing embryo implantation. The interaction between UC-MSCs and rat endometrial stromal cells (ESCs) was evaluated using a transwell 3D model and immunocytochemistry. Microarray mRNA and miRNA platforms were used for miRNA-mRNA expression profiling. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were performed to identify the biological processes, molecular functions, cellular components, and pathways of endometrial injury and UC-MSCs transplantation repair and real-time quantitative reverse transcription PCR (qRT-PCR) was performed to further identify the expression changes of key molecules in the pathways. Endometrium thickness, number of glands, and the embryo implantation numbers were improved, and the degree of fibrosis was significantly alleviated by UC-MSCs treatment in the rat model of thin endometrium. In vitro cell experiments showed that UC-MSCs migrated to injured ESCs and enhanced their proliferation. miRNA microarray chip results showed that expression of 45 miRNAs was downregulated in the injured endometrium and upregulated after UC-MSCs transplantation. Likewise, expression of 39 miRNAs was upregulated in the injured endometrium and downregulated after UC-MSCs transplantation. The miRNA-mRNA interactions showed the changes in the miRNA and mRNA network during the processes of endometrial injury and repair. GO and KEGG analyses showed that the process of endometrial injury was mainly attributed to the decomposition of the extracellular matrix (ECM), protein degradation and absorption, and accompanying inflammation. The process of UC-MSCs transplantation and repair were accompanied by the reconstruction of the ECM, regulation of chemokines and inflammation, and cell proliferation and apoptosis. The key molecules involved in ECM-receptor interaction pathways were further verified by qRT-PCR. Itga1 and Thbs expression decreased in the model group and increased by UC-MSCs transplantation, while Laminin and Collagen expression increased in both the model group and MSCs group, with greater expression observed in the latter. This study showed that UC-MSCs transplantation could promote recovery of thin endometrial morphology and function. Furthermore, it revealed the expression changes of miRNA and mRNA after endometrial injury and UC-MSCs transplantation repair processed, and signaling pathways that may be involved in endometrial injury and repair.

4.
Chemosphere ; 287(Pt 4): 132457, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34610373

RESUMO

Lead (Pb) is the most widely used anode in zinc (Zn) electrowinning and other metallurgical industries. The resource loss and environmental pollution caused by Pb anode corrosion are urgent problems to be solved. A γ-MnO2 precoated anode was prepared successfully to reduce the Pb-containing pollutant. The size effects with its controllable preparation on an industrial scale were studied. Severe nonuniform distribution of γ-MnO2 film was observed with curbing the reduction of anode slime only 68%, when anode size increased from lab to industry. Nonuniform rate (R) and average thickness (d) were found to be the key indicators to determine the film structure distribution and their performance differences, which were random and difficult to be controlled in scale-up size. However, a controllable industrial γ-MnO2 precoated anodes (IMPA) fabricated through optimized current density (J0) and electrodeposition time (t) in our developed film-forming system. Then, the long-term performances of two IMPA with different indicators (IMPA-1: R = 34%, d = 108 µm, IMPA-2: R = 23%, d = 55 µm) were compared with the industrial typical Pb-based anode (ITPA). Of the three different anodes, the optimized IMPA-2 displayed the best performance. Within 24 d of electrowinning cycle, the corrosion inhibition effect and the anode slime reduction rate for IMPA-2 improved by 56% and 30% than IMPA-1, and improved by 100% and 91% than ITPA. Furthermore, the mechanism analysis of size effect change showed that R of IMPA was contributed to the local gas holdup distribution along the anode. Controlled size effect of uniform oxide film will have a future application prospect for the sustainability of industry, which provides an important cleaner production of Zn electrowinning and related hydrometallurgy industries.


Assuntos
Poluentes Ambientais , Zinco , Eletrodos , Chumbo , Compostos de Manganês , Metalurgia , Óxidos
5.
Front Cardiovasc Med ; 8: 753627, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957243

RESUMO

In this report, we present a case study of an extremely rare left sinus Valsalva aneurysm (SVA) rupture into the left-ventricular myocardium. Acute ozone inhalation and long-term hypertension are possible contributors to the condition. Utilizing multimodal cardiovascular imaging techniques [echocardiogram, computed tomography (CT), and cardiac magnetic resonance (CMR)], a large, left-ventricular, intramural pseudoaneurysm (IPA) arising from the ruptured left SVA, was clearly observed anatomically and functionally. Subsequently, our patient underwent patch repair and valvoplasty which offered an excellent prognosis. This report describes the manifestation of the ruptured left SVA and its possible etiology. This case also emphasizes the need for multimodal imaging for subsequent surgical repair.

6.
Nanoscale ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34846404

RESUMO

The mismatch of thermal expansion coefficients (TECs) between cobalt-containing perovskite air electrodes and electrolytes is a great challenge for the development of thermo-mechanically durable solid oxide cells (SOCs). In this work, we propose a facile design principle to directly grow highly dispersed Co reactive sites onto ion-conducting scaffolds and confine the dimension of active centres within nanoscale. As a representative, the Co-socketed BaCe0.7Zr0.2Y0.1O3-δ perovskite (denoted as R-BCZY-Co) was constructed via a consecutive sol-gel and in situ exsolution approach. Combined XRD, H2-TPR, SEM and TEM results confirm the emergence of Co nanoparticles on a BCZY matrix without the segregation of a secondary Co-rich phase. The symmetric half-cell measurement suggests that R-BCZY-Co air electrode with the optimal Co content of 10 mol% exhibits a 7-fold promoted oxygen activation performance with a polarization resistance of ∼0.17 Ω cm2 at 750 °C. The TEC mismatch between fabricated R-BCZY-Co electrodes and BCZY electrolytes is minimized down to only ∼11.4%, which is significantly lower than that of other representative counterparts. Moreover, the detailed XPS result proves that the architecture of exsolved Co on BCZY possesses a higher concentration of surface oxygen vacancy, which further benefits the kinetics of ion diffusion and oxygen absorption.

7.
Sci China Life Sci ; 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34826093

RESUMO

Leucine-rich repeat containing G protein-coupled receptor 5 (Lgr5), a marker of intestinal stem cells (ISCs), is considered to play key roles in tissue homoeostasis and regeneration after acute radiation injury. However, the activation of Lgr5 by integrated signaling pathways upon radiation remains poorly understood. Here, we show that irradiation of mice with whole-body depletion or conditional ablation of REGγ in Lgr5+ stem cell impairs proliferation of intestinal crypts, delaying regeneration of intestine epithelial cells. Mechanistically, REGγ enhances transcriptional activation of Lgr5 via the potentiation of both Wnt and Hippo signal pathways. TEAD4 alone or cooperates with TCF4, a transcription factor mediating Wnt signaling, to enhance the expression of Lgr5. Silencing TEAD4 drastically attenuated ß-catenin/TCF4 dependent expression of Lgr5. Together, our study reveals how REGγ controls Lgr5 expression and expansion of Lgr5+ stem cells in the regeneration of intestinal epithelial cells. Thus, REGγ proteasome appears to be a potential therapeutic target for radiation-induced gastrointestinal disorders.

8.
BMC Geriatr ; 21(1): 641, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772361

RESUMO

BACKGROUND: Identifying practical and distinguished indicators and influencing factors of male aging may be useful in predicting subsequent aging trends, designing personalized prevention, and improving lifestyle and health. METHODS: A cross-sectional, population-based study was performed in Jiashan County, China in 2016. A total of 690 local male residents, aged 40 to 80 years, were eligible for recruitment. Demographic and lifestyle information was collected through structured interviews. A self-designed head scale, the Medical Outcomes Study 36-item Short Form (SF-36), International Index of Erectile Function (IIEF5), Aging Males' Symptoms (AMS), and International Prostate Symptom Score (IPSS) were used. Analysis of variance, local polynomial regression smoothing curves, multiple linear regression, and partial correlation analyses were performed. RESULTS: All the scales deteriorated with increasing age (P < 0.01), especially from the age of 60. The most significant changes between adjacent age groups were found in IIEF5 scores (16.7, 43.5 and 39.4%). Income, nutrition, personality and neighborhood relationship had an effect on SF-36 and AMS after adjusting for age (P < 0.01). Furthermore, neighborhood relationship modified the age effect on the head scale score and IIEF5 (P = 0.03); nutrition modified the relationship between age and SF-36 (P < 0.01). CONCLUSIONS: Recession of reproductive health may be a distinct predictor of male aging. The associations of social inequalities or personality and health offer potential interventions for men's health in aging. Self-reported scales may limit the precision and more physical fitness tests could be combined for a more precise assessment.


Assuntos
Envelhecimento , Nível de Saúde , Idoso , China , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
9.
Front Oncol ; 11: 706915, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604045

RESUMO

Background: Hepatocellular carcinoma is one of the most common malignant tumors with a very high mortality rate. The emergence of immunotherapy has brought hope for the cure of hepatocellular carcinoma. Only a small number of patients respond to immune checkpoint inhibitors, and ferroptosis and tertiary lymphoid structure contribute to the increased response rate of immune checkpoint inhibitors; thus, we first need to identify those who are sensitive to immunotherapy and then develop different methods to improve sensitivity for different groups. Methods: The sequencing data of hepatocellular carcinoma from The Cancer Genome Atlas and Gene Expression Omnibus was downloaded to identify the immune-related long non-coding RNAs (lncRNAs). LncRNAs related to survival data were screened out, and a risk signature was established using Cox proportional hazard regression model. R software was used to calculate the riskScore of each patient, and the patients were divided into high- and low-risk groups. The prognostic value of riskScore and its application in clinical chemotherapeutic drugs were confirmed. The relationship between riskScore and immune checkpoint genes, ferroptosis genes, and genes related to tertiary lymphoid structure formation was analyzed by Spearman method. TIMER, CIBERSORT, ssGSEA, and ImmuCellAI were used to evaluate the relative number of lymphocytes in tumor. The Wilcoxon signed-rank test confirmed differences in immunophenoscore between the high- and low-risk groups. Results: Data analysis revealed that our signature could well predict the 1-, 2-, 3-, and 5-year survival rates of hepatocellular carcinoma and to predict susceptible populations with Sorafenib. The risk signature were significantly correlated with immune checkpoint genes, ferroptosis genes, and tertiary lymphoid structure-forming genes, and predicted tumor-infiltrating lymphocyte status. There was a significant difference in IPS scores between the low-risk group and the high-risk group, while the low-risk group had higher scores. Conclusion: The riskScore obtained from an immune-related lncRNA signature could successfully predict the survival time and reflect the efficacy of immune checkpoint inhibitors. More importantly, it is possible to select different treatments for different hepatocellular carcinoma patients that increase the response rate of immune checkpoint inhibitors and will help improve the individualized treatment of hepatocellular carcinoma.

10.
Anal Chem ; 93(42): 14146-14152, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34648265

RESUMO

Second-harmonic generation (SHG) microscopy has been proved to be a powerful method for investigating the structures of biomaterials. SHG spectra were also generally used to probe the adsorption and cross-membrane transport of molecules on lipid bilayers in situ and in real time. In this work, we applied SHG and two-photon fluorescence (TPF) spectra to investigate the dynamics of an amphiphilic ion with an SHG and TPF chromophore, D289 (4-(4-diethylaminostyry)-1-methyl-pyridinium iodide), on the surface of human chronic myelogenous leukemia (K562) cells and the subcellular structures inside the cells. The adsorption and cross-membrane transport of D289 into the cells and then into the organelles such as mitochondria were revealed. SHG images were also recorded and used to demonstrate their capability of probing molecular dynamics in organelles in K562 cells. This work demonstrated the first SHG investigation of the cross-membrane transport dynamics on the surface of subcellular organelles. It may also shed light on the differentiation of different types of subcellular structures in cells.


Assuntos
Microscopia de Geração do Segundo Harmônico , Humanos , Microscopia , Simulação de Dinâmica Molecular , Organelas , Análise Espectral
11.
J Clin Lab Anal ; 35(12): e24062, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34689373

RESUMO

BACKGROUND: Previous studies found the dysbiosis of intestinal microbiota in diabetic kidney disease (DKD), especially the decreased SCFA-producing bacteria. We aimed to investigate the concentration of the stool and serum short-chain fatty acids (SCFAs), gut microbiota-derived metabolites, in individuals with DKD and reveal the correlations between SCFAs and renal function. METHODS: A total of 30 participants with DKD, 30 participants with type 2 diabetes mellitus (DM), and 30 normal controls (NC) in HwaMei Hospital were recruited from 1/1/2018 to 12/31/2019. Participants with DKD were divided into low estimated glomerular filtration rate (eGFR)(eGFR<60ml/min, n=14) and high eGFR (eGFR≥60ml/min, n=16) subgroups. Stool and serum were measured for SCFAs with gas chromatograph-mass spectrometry. RESULTS: The DKD group showed markedly lower levels of fecal acetate, propionate, and butyrate versus NC (p<0.001, p<0.001, p=0.018, respectively) [1027.32(784.21-1357.90)]vs[2064.59(1561.82-2637.44)]µg/g,[929.53(493.65-1344.26)]vs[1684.57(1110.54-2324.69)]µg/g,[851.39(409.57-1611.65)] vs[1440.74(1004.15-2594.73)]µg/g, respectively, and the lowest fecal total SCFAs concentration among the groups. DKD group also had a lower serum caproate concentration than that with diabetes (p=0.020)[0.57(0.47-0.61)]vs[0.65(0.53-0.79)]µmol/L. In the univariate regression analysis, fecal and serum acetate correlated with eGFR (OR=1.013, p=0.072; OR=1.017, p=0.032). The correlation between serum total SCFAs and eGFR showed statistical significance (OR=1.019, p=0.024) unadjusted and a borderline significance (OR=1.024, p=0.063) when adjusted for Hb and LDL. The decrease in serum acetate and total SCFAs were found of borderline significant difference in both subgroups (p=0.055, p=0.050). CONCLUSION: This study provides evidence that in individuals with DKD, serum and fecal SCFAs levels (fecal level in particular) were lowered, and there was a negative correlation between SCFAs and renal function.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34574635

RESUMO

DNA sequencing of active cells involved in vermicomposting can clarify the roles of earthworms in regulating functional microorganisms. This study aimed to investigate the effect of earthworms on functional microbial communities in sludge by comparing biodegradation treatments with and without earthworms. PCR and high throughput sequencing based on pretreatment of propidium monoazide (PMA) were used to detect the changes in active bacterial 16S rDNA and eukaryotic 18S rDNA during vermicomposting. The results showed that the nitrate in sludge vermicomposting and control were significantly different from day 10, with a more stable product at day 30 of vermicomposting. Compared with the control, the Shannon indexes of active bacteria and eukaryotes decreased by 1.9% and 31.1%, respectively, in sludge vermicompost. Moreover, Proteobacteria (36.2%), Actinobacteria (25.6%), and eukaryotic Cryptomycota (80.3%) were activated in the sludge vermicompost. In contrast, the control had Proteobacteria (44.8%), Bacteroidetes (14.2%), Cryptomycota (50.00%), and Arthropoda (36.59%). Network analysis showed that environmental factors had different correlations between active bacterial and eukaryotic community structures. This study suggests that earthworms can decrease the diversity of bacterial and eukaryotic communities, forming a specific-functional microbial community and thus accelerating organic matter decomposition during vermicomposting of dewatered sludge.


Assuntos
Oligoquetos , Animais , Bactérias/genética , DNA Ribossômico , Eucariotos , Esgotos , Solo
13.
Am J Mens Health ; 15(5): 15579883211049044, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34581214

RESUMO

The objective of the current study was to explore the relationship between longitudinal change in body mass index (BMI) and reproductive hormones in middle-aged and elderly Chinese men. A cohort study was conducted in a rural area of China. Local male residents aged 40-80 years were recruited at baseline in 2012 and were followed up in 2016. Information about weight, height, waist circumference, sex hormones, smoking status, and medical history were obtained. The change in BMI reported no significant relationship with the change in total testosterone (TT), calculated free testosterone (cFT), and bioavailable testosterone (BioT) in Pearson correlation analyses. When the change in BMI was divided into three groups-"great loss," "normal fluctuation," and "great gain"-TT, cFT and BioT had the highest increase (or the lowest decrease) in men with "normal fluctuation" in BMI compared with the other two groups. The advantage of maintaining a stable BMI was more evident for those who were overweight, non-smoking, and disease-free. There was a tendency of a continuous increase in cFT and BioT with BMI increase in smoking and diseased populations. Maintaining a stable BMI is associated with maintaining normal levels of reproductive hormones, especially in overweight, non-smoking, and healthy men aged over 40 years.


Assuntos
Globulina de Ligação a Hormônio Sexual , Testosterona , Idoso , Índice de Massa Corporal , Estudos de Coortes , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
14.
Cancer Cell Int ; 21(1): 500, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535132

RESUMO

BACKGROUND: The prognosis of hepatocellular carcinoma (HCC) is not optimistic. Our study focused on present inflammatory markers, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), gamma-glutamyl transpeptidase-to-platelet ratio (GPR), aspartate aminotransferase-to-lymphocyte ratio (ALR) and fibrinogen-to-albumin ratio (FAR), and explored their optimal combination for the prognosis of HCC after resection. METHODS: A total of 347 HCC patients who underwent curative resection were enrolled. The optimal cutoff values of the inflammatory markers were calculated using receiver operating characteristic (ROC) curve analysis, and used to divide patients into two groups whose differences were compared by Kaplan-Meier analysis. Cox univariate and multivariate analyses were used to analyze the independent prognostic inflammatory markers. The χ2 test was chosen to determine the relationship between independent prognostic inflammatory markers and clinicopathological features. We created combined scoring models and evaluated them by Cox univariate and multivariate methods. The concordance index (C-index), Akaike information criterion (AIC) and likelihood ratio were calculated to compare the models. The selected optimal inflammatory markers and their combinations were tested in different stages of HCC by Kaplan-Meier analysis. RESULTS: The ALR and GPR were independent prognostic factors for disease-free survival (DFS); the ALR, PLR, and GPR were independent prognostic factors for overall survival (OS). The proposed GPR and ALR-GPR-PLR score models were independent predictors for DFS and OS, respectively. CONCLUSION: The preoperative GPR and ALR-GPR-PLR score models were independent predictors for DFS and OS, respectively, and performed well in stratifying patients with HCC. The higher the score in the model was, the worse the prognosis.

15.
Mil Med Res ; 8(1): 51, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517915

RESUMO

To determine the prevalence and clinical features of olfactory and taste disorders among coronavirus disease 2019 (COVID-19) patients in China. A cross-sectional study was performed in Wuhan from April 3, 2020 to April 15, 2020. A total of 187 patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) completed face-to-face interviews or telephone follow-ups. We found that the prevalence of olfactory and taste disorders was significantly lower in the Chinese cohort than in foreign COVID-19 cohorts. Females were more prone to olfactory and taste disorders. In some patients, olfactory and taste disorders precede other symptoms and can be used as early screening and warning signs.


Assuntos
COVID-19/complicações , Transtornos do Olfato/etiologia , Olfato , Distúrbios do Paladar/etiologia , Paladar , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/epidemiologia , Prevalência , SARS-CoV-2 , Fatores Sexuais , Distúrbios do Paladar/epidemiologia , Adulto Jovem
16.
mBio ; 12(5): e0209921, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34544273

RESUMO

The two-component system PhoP/PhoQ is essential for Salmonella enterica serovar Typhimurium virulence. Here, we report that PhoP is methylated extensively. Two consecutive glutamate (E) and aspartate (D)/E residues, i.e., E8/D9 and E107/E108, and arginine (R) 112 can be methylated. Individual mutation of these above-mentioned residues caused impaired phosphorylation and dimerization or DNA-binding ability of PhoP to a different extent and led to attenuated bacterial virulence. With the help of specific antibodies recognizing methylated E8 and monomethylated R112, we found that the methylation levels of E8 or R112 decreased dramatically when bacteria encountered low magnesium, acidic pH, or phagocytosis by macrophages, under which PhoP can be activated. Furthermore, CheR, a bacterial chemotaxis methyltransferase, was identified to methylate R112. Overexpression of cheR decreased PhoP activity but increased PhoP stability. Together, the current study reveals that methylation plays an important role in regulating PhoP activities in response to environmental cues and, consequently, modulates Salmonella virulence. IMPORTANCE Posttranslational modifications (PTMs) play an important role in regulating enzyme activities, protein-protein interactions, or DNA-protein recognition and, consequently, modulate many biological functions. We demonstrated that PhoP, the response regulator of PhoP/PhoQ two-component system, could be methylated on several evolutionally conserved amino acid residues. These amino acid residues were crucial for PhoP phosphorylation or dimerization, DNA-binding ability of PhoP, and Salmonella virulence. Interestingly, methylation negatively regulated the activity of PhoP. A bacterial chemotaxis methyltransferase CheR was involved in PhoP methylation. Methylation of PhoP could stabilize it in an inactive conformation. Our work provides a more informative depiction of PhoP PTM and markedly improves our understanding of the coordinate regulation of bacterial chemotaxis and virulence.

17.
Cell Biosci ; 11(1): 150, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34344450

RESUMO

INSTRUCTION: Lead (Pb) exposure is a risk factor for male infertility, but the epigenetic changes in sperm DNAattributable to lead exposure is poorly defined. METHODS: In this study, we investigated whether low Pb exposure (< 10 µg/dL) affects the sperm quality. Blood, urine, and semen samples of 297 men of childbearing age were analyzed for all relevant parameters. Based on the blood Pb level (BLL), participants were allocated to RL (0-2.5 µg/dL), RM (2.5-5 µg/dL), and RH (5-10 µg/dL) groups. The 5-methylcytosine and 5-hydroxymethylcytosine patterns in the sperm DNA were identified using methylated DNA immunoprecipitation and hydroxymethylated DNA immunoprecipitation sequencing. RESULTS: The non-progressive motility (NP) was significantly increased and associated with global hypomethylation of sperm DNA in the RH group compared with the RL group, indicating that aberrant sperm methylation due to low Pb exposure is possibly associated with reduced sperm motility. The hypomethylated promoter regions were primarily enriched in the calcium (Ca) homeostasis pathway. Further, the interaction between Ca and Pb was associated with sperm rapid progressive motility and asthenospermia risk, although no significant methylation abnormality was observed in those with BLL < 5 µg/dL. When BLL was > 5 µg/dL or when predicting NP, no significant Pb-Ca interaction was observed. DISCUSSION: Overall, our results indicate that aberrant DNA methylation of the Ca homeostasis pathway, induced by low Pb exposure, is the potential cause for reduced sperm velocity.

18.
Asian J Surg ; 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34384677

RESUMO

AIM: There lacks a predictive model for overall survival (OS) of node-negative perihilar cholangiocarcinoma (PHC). This study aimed at developing and validating a prognostic nomogram to predict OS of node-negative PHC after resection. METHODS: We established a nomogram via multivariate regression analysis by using the design cohort (n = 410, obtained from Surveillance, Epidemiology, and End Results database), and its external verification was done in the validation cohort (n = 100, the First Affiliated Hospital of Sun Yat-sen University). Predictive accuracy of the nomogram was assessed by concordance-index (C-index), calibration curves, and decision curve analysis (DCA). Performance of the nomogram was compared with the American Joint Committee on Cancer (AJCC) staging system. RESULTS: Multivariate regression analysis revealed that age, tumor grade, and the count of examined lymph nodes were independent prognostic factors for OS of node-negative PHC. The nomogram had a C-index of 0.603 and 0.626 in design cohort and validation cohort, respectively, which was better than that of AJCC staging system (both p < 0.05). The calibration curves showed good consistency between actual and nomogram-predicted OS probabilities. DCA showed that nomogram had better clinical usefulness. Furthermore, the nomogram-predicted scores could stratify the patients into three risk groups, and patients in higher risk group had worse prognosis than those in lower risk group (all p < 0.05). CONCLUSION: The proposed nomogram had a better prognostic accuracy than the AJCC staging system in predicting postoperative OS of node-negative PHC. It was helpful to guide the adjuvant therapeutic strategies for node-negative PHC.

19.
Regen Med ; 16(9): 833-846, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34463127

RESUMO

Objective: A model of alveolar cleft phenotype was established in rabbits to evaluate the effect of active bone particles containing modified rhecombinant human BMP-2 on the repair of the alveolar cleft. Methods: 2-month-old Japanese white rabbits were selected and randomly divided into four groups: normal, control, material and BMP groups. Blood biochemical analysis, skull tomography (microfocus computerized tomography), and histological and immunohistochemical staining analysis of paraffin sections were performed 3  and 6 months after operation. Results: Both types of collagen particles showed good biocompatibility and promoted bone regeneration. The effect of active bone particles on bone repair and regeneration was better than that of bone collagen particles. Conclusions: Active bone particles containing modified rhecombinant human BMP-2 can be used for incisors regeneration.


Assuntos
Proteína Morfogenética Óssea 2 , Regeneração Óssea , Fator de Crescimento Transformador beta , Animais , Proteína Morfogenética Óssea 2/administração & dosagem , Colágeno , Modelos Animais de Doenças , Coelhos , Distribuição Aleatória , Proteínas Recombinantes/administração & dosagem , Crânio/diagnóstico por imagem
20.
Stem Cell Rev Rep ; 2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34420159

RESUMO

BACKGROUND: Most materials used clinically for filling severe bone defects either cannot induce bone re-generation or exhibit low bone conversion, therefore, their therapeutic effects are limited. Human umbilical cord mesenchymal stem cells (hUC-MSCs) exhibit good osteoinduction. However, the mechanism by which combining a heterogeneous bone collagen matrix with hUC-MSCs to repair the bone defects of alveolar process clefts remains unclear. METHODS: A rabbit alveolar process cleft model was established by removing the bone tissue from the left maxillary bone. Forty-eight young Japanese white rabbits (JWRs) were divided into normal, control, material and MSCs groups. An equal volume of a bone collagen matrix alone or combined with hUC-MSCs was implanted in the defect. X-ray, micro-focus computerized tomography (micro-CT), blood analysis, histochemical staining and TUNEL were used to detect the newly formed bone in the defect area at 3 and 6 months after the surgery. RESULTS: The bone formation rate obtained from the skull tissue in MSCs group was significantly higher than that in control group at 3 months (P < 0.01) and 6 months (P < 0.05) after the surgery. The apoptosis rate in the MSCs group was significantly higher at 3 months after the surgery (P < 0.05) and lower at 6 months after the surgery (P < 0.01) than those in the normal group. CONCLUSIONS: Combining bone collagen matrix with hUC-MSCs promoted the new bone regeneration in the rabbit alveolar process cleft model through promoting osteoblasts formations and chondrocyte growth, and inducing type I collagen formation and BMP-2 generation.

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