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1.
Nat Commun ; 15(1): 4333, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773099

RESUMO

Earth's lower mantle is a potential water reservoir. The physical and chemical properties of the region are in part controlled by the Fe3+/ΣFe ratio and total iron content in bridgmanite. However, the water effect on the chemistry of bridgmanite remains unclear. We carry out laser-heated diamond anvil cell experiments under hydrous conditions and observe dominant Fe2+ in bridgmanite (Mg, Fe)SiO3 above 105 GPa under the normal geotherm conditions corresponding to depth > 2300 km, whereas Fe3+-rich bridgmanite is obtained at lower pressures. We further observe FeO in coexistence with hydrous NiAs-type SiO2 under similar conditions, indicating that the stability of ferrous iron is a combined result of H2O effect and high pressure. The stability of ferrous iron in bridgmanite under hydrous conditions would provide an explanation for the nature of the low-shear-velocity anomalies in the deep lower mantle. In addition, entrainment from a hydrous dense layer may influence mantle plume dynamics and contribute to variations in the redox conditions of the mantle.

2.
J Am Chem Soc ; 145(44): 24284-24293, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888942

RESUMO

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

3.
iScience ; 26(9): 107455, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37680481

RESUMO

Type H vessels couple angiogenesis with osteogenesis, while sympathetic cues regulate vascular and skeletal function. The crosstalk between sympathetic nerves and type H vessels in bone remains unclear. Here, we first identify close spatial connections between sympathetic nerves and type H vessels in bone, particularly in metaphysis. Sympathoexcitation, mimicked by isoproterenol (ISO) injection, reduces type H vessels and bone mass. Conversely, beta-2-adrenergic receptor (ADRB2) deficiency maintains type H vessels and bone mass in the physiological condition. In vitro experiments reveal indirect sympathetic modulation of angiogenesis via paracrine effects of mesenchymal stem cells (MSCs), which alter the transcription of multiple angiogenic genes in endothelial cells (ECs). Furthermore, Notch signaling in ECs underlies sympathoexcitation-regulated type H vessel formation, impacting osteogenesis and bone mass. Finally, propranolol (PRO) inhibits beta-adrenergic activity and protects type H vessels and bone mass against estrogen deficiency. These findings unravel the specialized neurovascular coupling in bone homeostasis and regeneration.

4.
Cancer Med ; 12(15): 16119-16128, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37351559

RESUMO

BACKGROUND: Liver transplantation has made significant progress in recent decades. Lung cancer is one of the most frequently occurring cancers after liver transplantation. However, the risk of lung cancer among liver transplant patients compared with the general population is unclear. The aim of this meta-analysis was to assess the risk of developing lung cancer after liver transplantation. METHODS: All eligible studies published in PubMed, Web of Science, and Embase from database inception to April 2022 were included. Standardized incidence ratio was used to describe the increased risk of lung cancer in liver transplant recipients as compared with the general population. The random-effects model was used for the calculations. A funnel plot and Egger test were performed to assess the potential publication bias. RESULTS: Our meta-analysis included 15 studies, which involved 76,897 liver transplantation patients. Studies included in this review showed significant heterogeneity (I2 = 65.3%; p < 0.001), which required a random-effects model for effect pooling. The results indicated a significant higher risk of developing lung cancer in liver transplant patients than the general population with a pooled SIR of 2.06 (95% CI: 1.73, 2.46, p < 0.001). When stratified by region, no significant regional difference was observed. It showed a similarly doubled risk of lung cancer in Europe and North America, but an insignificantly increased risk in Asian populations. The sensitivity analysis by removal and substitution of each literature did not change the results. CONCLUSION: Our meta-analysis suggests that liver transplant patients are twice as likely as the general population to develop lung cancer. Further research on risk factors for the development of lung cancer after liver transplantation should be conducted and appropriate surveillance protocols should be developed to reduce the risk of its occurrence.


Assuntos
Transplante de Fígado , Neoplasias Pulmonares , Humanos , Transplante de Fígado/efeitos adversos , Incidência , Fatores de Risco , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , América do Norte
5.
Front Surg ; 9: 800050, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35310448

RESUMO

Castleman disease (CD) rarely presents with obstructive jaundice, which poses a diagnostic and therapeutic challenge to the management of the disease. A 40-year-old man was referred to our hospital for emergent management of upper abdominal pain. An abdominal mass was removed, and the postoperative pathology showed retroperitoneum CD, which was subsequently managed by adjuvant therapy of combination chemotherapy and steroids. One month later, a biliary metal stent was placed due to the presentation of obstructive jaundice. After ~3 months, the patient experienced another episode of obstructive jaundice, and SpyGlass DS cholangioscopy was performed via the biliary tract for biopsy, which pathologically showed biliary malignancies. Radiofrequency ablation was performed with a probe, and another uncovered metal stent was placed within the existing metal stent. No stent occlusion occurred during a 6-month follow-up period. In conclusion, CD rarely presents with obstructive jaundice, and a combination of radiofrequency ablation with metal stent implantation under cholangioscopy can prolong the stent patency time and the survival time of patients.

6.
J Oral Rehabil ; 49(2): 249-257, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34865233

RESUMO

BACKGROUND AND OBJECTIVE: Psychological stress causes structural and metabolic dysfunction of masseter muscles. The anti-inflammatory and anti-oxidative polyphenol curcumin plays a local antioxidant role in rat masseter muscles under psychological stress by an as-yet-unknown mechanism. The present study aimed to assess curcumin anti-inflammatory and anti-oxidative effects on masseter muscle and its possible molecular mechanisms. METHODS: We constructed a rat model of chronic unpredictable moderate stress (CUMS). Psychological stress was assessed by determining the levels of adrenocorticotropic hormone (ACTH) and cortisol in serum. Enzyme-linked immunosorbent assays measured inflammatory cytokines and markers of oxidative stress in masseter muscles. Levels of high-mobility group box 1 (HMGB1), interleukin (IL)-1ß, IL-6 and tumour necrosis factor-alpha (TNF-α) were determined using quantitative PCR analyses and immunofluorescent staining. Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NF-κB) activation were examined using western blotting. RESULTS: The CUMS group showed increased serum cortisol and ACTH levels. Pathological changes in the ultrastructure, oxidative stress and inflammatory cytokines in the masseter muscles were also observed. Curcumin treatment (50, 100 mg/kg) ameliorated these changes significantly by varying degrees. Mechanistically, increased levels of phosphorylated NF-κB, toll-like receptor 4 and HMGB1 were observed, which were also ameliorated by curcumin treatment. CONCLUSION: Curcumin can reduce local pathological changes, levels of oxidative stress and inflammatory factors in masseter muscles. Psychological stress activates HMGB1 expression and increases the expression of downstream TLR4 and p-NF-κB, which could be reduced by curcumin. Thus, curcumin might exert anti-inflammatory and antioxidant effects in masseter muscles via the HMGB1/TLR4/NF-κB pathway.


Assuntos
Curcumina , Proteína HMGB1 , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Curcumina/farmacologia , Proteína HMGB1/metabolismo , Proteína HMGB1/farmacologia , Músculo Masseter/metabolismo , NF-kappa B/metabolismo , NF-kappa B/farmacologia , Ratos , Transdução de Sinais , Estresse Psicológico/tratamento farmacológico , Receptor 4 Toll-Like
7.
Eur J Gastroenterol Hepatol ; 32(10): 1273-1278, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32398494

RESUMO

The purpose of this systematic review and meta-analysis was to investigate the relationship between liver transplantation and kidney cancer. Preferred Reporting Items for Systematic reviews and Meta-Analysis guidelines were followed. PubMed, the Web of Science, and the Cochrane databases were searched for peer-reviewed cohort studies in which standardized incidence of kidney cancer post-transplant was compared to the general population by means of standardized incidence ratio (SIR) with 95% confidence interval (CI). No limits were placed on language or year of publication. A fixed-effects model was used for pooling the data. Of the 937 citations identified from the electronic databases, we included nine cohort studies with 53913 liver transplant patients, a male percentage of 56.8% and a minimum follow-up of 12.4 months and more. The meta-analysis revealed that liver transplant recipients faced a significantly higher risk of developing kidney cancer than the general population with the pooled SIR of 2.02 (95% CI, 1.64-2.50; P < 0.001). No significant between-study heterogeneity was observed (I = 0, Phet = 0.553). On sensitivity analysis after removing the study by Engles et al. with the largest sample size (37 888 liver transplant recipients), the SIR remained stable (SIR 2.75; 95% CI, 1.85-4.10; P < 0.001). Overall, our synthesis of the literature indicates that an increased risk of kidney cancer exists after liver transplantation. Future studies should evaluate the potential risk factors associated with kidney cancer.


Assuntos
Neoplasias Renais , Transplante de Fígado , Estudos de Coortes , Humanos , Incidência , Transplante de Fígado/efeitos adversos , Masculino , Fatores de Risco
8.
World J Clin Cases ; 8(2): 464-470, 2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-32047799

RESUMO

BACKGROUND: Gallbladder adenomyomatosis (GAM) is a benign lesion, characterized by thickening of the gallbladder wall and a focal mass, which overlap with the features of gallbladder malignancy. Consequently, differential diagnosis of GAM from gallbladder cancer is difficult and approximately 20% of suspected malignant biliary strictures are postoperatively confirmed as benign lesions. Herein, we report a case in which a preoperative diagnosis of GAM was made by a combination of endoscopic and imaging techniques. CASE SUMMARY: A 40-year-old man was referred to our hospital chiefly for a fever and right upper abdominal pain with dark urine. Enhanced computed tomography showed thickening of the gallbladder wall and a mass in the gallbladder neck with involvement of the hepatic bile ducts, which was suspected to be malignant. Gallbladder malignancy with bile duct invasion was ruled out by subsequent endoscopic examinations, including endoscopic retrograde cholangio-pancreatography, intraductal ultrasound, and SpyGlass. Endoscopic examinations showed a homogeneous hyperechoic lesion with smooth margins of benign bile duct stricture suggestive of inflammatory stenosis of the bile duct. The patient underwent laparoscopic cholecystectomy. GAM was postoperatively diagnosed and confirmed based on the histopathology results, which are consistent with the preoperative diagnosis. Notably, no malignant event occurred in the patient during a 12-mo follow-up period. CONCLUSION: A combination of endoscopic techniques may help in the differential diagnosis of GAM from gallbladder cancer.

9.
World J Surg Oncol ; 18(1): 21, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31987047

RESUMO

BACKGROUND: Aldehyde dehydrogenase 2 (ALDH2) and cytochrome p450 2E1 (CYP2E1) are important alcohol-metabolizing enzymes. The aim of this meta-analysis was to evaluate the association of ALDH2 rs671 and CYP2E1 rs2031920 polymorphisms with hepatocellular carcinoma (HCC) susceptibility in East Asians. METHODS: A systematic search strategy was implemented in MEDLINE, PubMed, Scopus, Embase, and China Academic Journals databases. Nineteen case-control studies were selected for inclusion. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated through random-effects or fixed-effects models. Subgroup analysis, meta-regression, sensitivity analysis, cumulative meta-analysis, and evaluation of publication bias were performed. RESULTS: The overall meta-analysis did not find a significant association of ALDH2 rs671 and CYP2E1 rs2031920 genotypes with HCC susceptibility in East Asians. In addition, stratified analysis by country, Hardy-Weinberg equilibrium status, and source of controls also did not identify any association. CONCLUSION: The ALDH2 rs671 and CYP2E1 rs2031920 polymorphisms are not associated with HCC susceptibility in East Asians.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Carcinoma Hepatocelular/genética , Citocromo P-450 CYP2E1/genética , Neoplasias Hepáticas/genética , Povo Asiático/genética , Estudos de Associação Genética , Genótipo , Humanos , Polimorfismo Genético , Prognóstico
10.
Stem Cell Res Ther ; 10(1): 298, 2019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547887

RESUMO

BACKGROUND: Although tissue-engineered cartilage has been broadly studied, complete integration of regenerated cartilage with residual cartilage is still difficult for the inferior mechanical and biochemical feature of neocartilage. Chondrogenesis of mesenchymal stem cells can be induced by biophysical and biochemical factors. METHODS: In this study, autologous platelet-rich fibrin (PRF) membrane was used as a growth factor-rich scaffold that may facilitate differentiation of the transplanted bone marrow mesenchymal stem cells (BMSCs). At the same time, hydrostatic pressure was adopted for pre-adjustment of the seed cells before transplantation that may promote the mechanical flexibility of neocartilage. RESULTS: An in vitro study showed that the feasible hydrostatic pressure stimulation substantially promoted the chondrogenic potential of in vitro-cultured BMSC/PRF construct. In vivo results revealed that at every time point, the newborn tissues were the most favorable in the pressure-pretreated BMSC/PRF transplant group. Besides, the transplantation of feasible hydrostatic pressure-pretreated construct by BMSC sheet fragments and PRF granules could obviously improve the integration between the regenerated cartilage and host cartilage milieu, and thereby achieve boundaryless repair between the neocartilage and residual host cartilage tissue in rabbit temporomandibular joints. It could be concluded that feasible hydrostatic pressure may effectively promote the proliferation and chondrogenic differentiation of BMSCs in a BMSC/PRF construct. CONCLUSION: This newly formed construct with biomechanical flexibility showed a superior capacity for cartilage regeneration by promoting the mechanical properties and integration of neocartilage.


Assuntos
Cartilagem Articular/fisiologia , Pressão Hidrostática , Células-Tronco Mesenquimais/citologia , Regeneração , Alicerces Teciduais/química , Animais , Cartilagem Articular/citologia , Diferenciação Celular , Células Cultivadas , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Fibrina Rica em Plaquetas/química , Coelhos
11.
Sci Rep ; 9(1): 12642, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477767

RESUMO

Anthrax toxin protein receptor (ANTXR) 1 has many similarities to integrin and is regarded in some respects as a single-stranded integrin protein. However, it is not clear whether ANTXR1 responds to mechanical signals secondary to the activation of integrins or whether it is a completely new, independent and previously undiscovered mechanosensor that responds to an undefined subset of mechanical signaling molecules. Our study demonstrates that ANTXR1 is a novel mechanosensor on the cell membrane, acting independently from the classical mechanoreceptor molecule integrinß1. We show that bone marrow stromal cells (BMSCs) respond to the hydrostatic pressure towards chondrogenic differentiation partly through the glycogen synthase kinase (GSK) 3ß/ß-Catenin signaling pathway, which can be partly regulated by ANTXR1 and might be related to the direct binding between ANTXR1 and low-density lipoprotein receptor-related protein (LRP) 5/6. In addition, ANTXR1 specifically activates Smad2 and upregulates Smad4 expression to facilitate the transport of activated Smad2 to the nucleus to regulate chondrogenesis, which might be related to the direct binding between ANTXR1 and Actin/Fascin1. We also demonstrate that ANTXR1 binds to some extent with integrinß1, but this interaction does not affect the expression and function of either protein under pressure. Thus, we conclude that ANTXR1 plays a crucial role in BMSC mechanotransduction and controls specific signaling pathways that are distinct from those of integrin to influence the chondrogenic responses of BMSCs under hydrostatic pressure.


Assuntos
Pressão Hidrostática , Mecanotransdução Celular , Células-Tronco Mesenquimais/metabolismo , Receptores de Peptídeos/metabolismo , Animais , Células Cultivadas , Condrogênese , Citoesqueleto/metabolismo , Regulação para Baixo , Integrina beta1/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Modelos Biológicos , Ligação Proteica , Ratos Sprague-Dawley , Transdução de Sinais
12.
J Appl Gerontol ; 38(6): 884-901, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-28653557

RESUMO

This study compared urban/rural trends in cigarette smoking rates among older male adults in China. Data were derived from the China Health and Nutrition Survey ( N = 5,147). Logistic models were computed to assess the occurrence of cigarette smoking between 1991 and 2011 across urban/rural administrative districts. Cigarette smoking rates remained consistent (about 50%) in rural villages over the last two decades but decreased by about 1.1 percentage points annually in urban neighborhoods. After adjusting for individual and community characteristics, divergent urban/rural trends in cigarette smoking rates did not vary statistically. Trends in cigarette smoking may be associated with unbalanced social and economic development in urban and rural China, and are an indicator of social determinants of health inequalities. Results suggest tobacco control policies and interventions should specifically focus on older adults vulnerable to economic inequality. Findings have implications for health and economic inequality among older adults in general.


Assuntos
Fumar Cigarros/epidemiologia , População Rural/tendências , População Urbana/tendências , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , População Rural/estatística & dados numéricos , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
13.
Int J Mol Sci ; 18(5)2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28513573

RESUMO

The present study aimed to analyze novel mechanisms underlying Nrf2-mediated anti-apoptosis in periodontal ligament stem cells (PDLSCs) in the periodontitis oxidative microenvironment. We created an oxidative stress model with H2O2-treated PDLSCs. We used real-time PCR, Western blotting, TUNEL staining, fluorogenic assay and transfer genetics to confirm the degree of oxidative stress and apoptosis as well as the function of nuclear factor-erythroid 2-related factor 2 (Nrf2). We demonstrated that with upregulated levels of reactive oxygen species (ROS) and malondialdehyde (MDA), the effect of oxidative stress was obvious under H2O2 treatment. Oxidative molecules were altered after the H2O2 exposure, whereby the signaling of Nrf2 was activated with an increase in its downstream effectors, heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1) and γ-glutamyl cysteine synthetase (γ-GCS). Additionally, the apoptosis levels gradually increased with oxidative stress by the upregulation of caspase-9, caspase-3, Bax and c-Fos levels in addition to the downregulation of Bcl-2. However, there was no alterations in levels of caspase-8. The enhanced antioxidant effect could not mitigate the occurrence of apoptosis. Furthermore, Nrf2 overexpression effectively improved the anti-oxidative levels and increased cell proliferation. At the same time, overexpression effectively restrained TUNEL staining and decreased the molecular levels of caspase-9, caspase-3, Bax and c-Fos, but not that of caspase-8. In contrast, silencing the expression of Nrf2 levels had the opposite effect. Collectively, Nrf2 alleviates PDLSCs via its effects on regulating oxidative stress and anti-intrinsic apoptosis by the activation of oxidative enzymes.


Assuntos
Apoptose , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Ligamento Periodontal/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Expressão Gênica , Inativação Gênica , Humanos , Peróxido de Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2/genética , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Ann Biomed Eng ; 44(10): 2971-2983, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27256361

RESUMO

This study aimed to investigate the differential and synergistic effects of mechanical stimulation and estrogen on the proliferation and osteogenic or chondrogenic differentiation potential of bone marrow mesenchymal stem cells (BMSCs) and the roles of estrogen receptor (ER) in them. BMSCs were isolated and cultured using the whole bone marrow adherence method, and flow cytometry was used to identify the surface marker molecules of BMSCs. Cells were pre-treated with 1 nM 17ß-estradiol or 1 nM of the estrogen receptor antagonist tamoxifen. Then, the cells were stimulated with hydrostatic pressure. Assessment included flow cytometry analysis of the cell cycle; immunofluorescent staining for F-actin; protein quantification for MAPK protein; and mRNA analysis for Col I, OCN, OPN and BSP after osteogenic induction and Sox-9, Aggrecan and Col-II after chondrogenic induction. Hydrostatic pressure (90 kPa/1 h) and 1 nM 17ß-estradiol enhanced the cellular proliferation ability and the cytoskeleton activity but without synergistic biological effects. Estrogen activated ERKs and JNKs simultaneously and promoted the osteogenic differentiation, whereas the pressure just caused JNK-1/2 activation and promoted the chondrogenic differentiation of BMSCs. Estrogen had antagonism effect on chondrogenic promotion of hydrostatic pressure. Mechanobiological effects of hydrostatic pressure are closely associated with ERα activity. MAPK molecules and F-actin were likely to be important mediator molecules in the ER-mediated mechanotransduction of BMSCs.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Mecanotransdução Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Animais , Células da Medula Óssea/citologia , Receptor alfa de Estrogênio/agonistas , Feminino , Pressão Hidrostática , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Sprague-Dawley , Tamoxifeno/farmacologia
15.
Int J Public Health ; 61(4): 417-25, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26841892

RESUMO

OBJECTIVES: This study compared urban/rural differences in smoking initiation during the transition from adolescence to young adulthood among Chinese males. METHODS: Data were derived from the China Health and Nutrition Survey (N = 2395). Logistic and cox models were computed to assess smoking initiation between the ages of 15 and 20 across urban/rural administrative districts (i.e. urban neighborhood, suburban village, county town neighborhood, and rural village). RESULTS: Findings revealed that rates of smoking initiation decreased from the 1970 to 1996 cohorts in all four administrative districts. After adjusting for household and community characteristics, the inverse association between smoking initiation and birth year remained statistically significant (p < 0.05) in all administrative districts with the exception of urban neighborhoods. County town neighborhoods and suburban villages witnessed accelerated reductions in smoking initiation. CONCLUSIONS: Decreased smoking initiation appears to be associated with birth year, which may be correlated with social and economic development of China in conjunction with an unprecedented rate of urbanization. Results suggest that the rate of smoking initiation for male youths may experience further decreases, particularly in areas with a heightened potential of urbanization.


Assuntos
População Rural/estatística & dados numéricos , Fumar/epidemiologia , População Urbana/estatística & dados numéricos , Adolescente , Fatores Etários , China/epidemiologia , Humanos , Modelos Logísticos , Masculino , Fatores Socioeconômicos , Adulto Jovem
16.
Stem Cell Res ; 14(3): 283-96, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25794483

RESUMO

Our previous studies have shown that hydrostatic pressure can serve as an active regulator for bone marrow mesenchymal stem cells (BMSCs). The current work further investigates the roles of cytoskeletal regulatory proteins Ras homolog gene family member A (RhoA) and Ras-related C3 botulinum toxin substrate 1 (Rac1) in hydrostatic pressure-related effects on BMSCs. Flow cytometry assays showed that the hydrostatic pressure promoted cell cycle initiation in a RhoA- and Rac1-dependent manner. Furthermore, fluorescence assays confirmed that RhoA played a positive and Rac1 displayed a negative role in the hydrostatic pressure-induced F-actin stress fiber assembly. Western blots suggested that RhoA and Rac1 play central roles in the pressure-inhibited ERK phosphorylation, and Rac1 but not RhoA was involved in the pressure-promoted JNK phosphorylation. Finally, real-time polymerase chain reaction (PCR) experiments showed that pressure promoted the expression of osteogenic marker genes in BMSCs at an early stage of osteogenic differentiation through the up-regulation of RhoA activity. Additionally, the PCR results showed that pressure enhanced the expression of chondrogenic marker genes in BMSCs during chondrogenic differentiation via the up-regulation of Rac1 activity. Collectively, our results suggested that RhoA and Rac1 are critical to the pressure-induced proliferation and differentiation, the stress fiber assembly, and MAPK activation in BMSCs.


Assuntos
Diferenciação Celular , Mecanotransdução Celular , Células-Tronco Mesenquimais/citologia , Proteínas rac1 de Ligação ao GTP/fisiologia , Proteína rhoA de Ligação ao GTP/fisiologia , Animais , Ciclo Celular , Regulação para Baixo , Citometria de Fluxo , Marcadores Genéticos , Pressão Hidrostática , Microscopia de Fluorescência , Modelos Biológicos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
17.
Cell Tissue Res ; 361(2): 439-55, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25797716

RESUMO

Our aim is to investigate the cytobiological effects of autologous platelet-rich fibrin (PRF) on dental pulp stem cells (DPSCs) and to explore the ectopic and orthotopic possibilities of dental pulp revascularization and pulp-dentin complex regeneration along the root canal cavities of the tooth by using a novel tissue-engineered transplant composed of cell-sheet fragments of DPSCs and PRF granules. Canine DPSCs were isolated and characterized by assaying their colony-forming ability and by determining their cell surface markers and osteogenic/adipogenic differentiation potential. The biological effects of autologous PRF on DPSCs, including cell proliferation, alkaline phosphatase (ALP) activity and odonto-/osteogenic gene expression, were then investigated and quantified. A novel transplant consisting of cell-sheet fragments of DPSCs and PRF granules was adopted to regenerate pulp-dentin-like tissues in the root canal, both subcutaneously in nude mice and in the roots of canines. PRF promoted the proliferation of DPSCs in a dose- and time-dependent manner and induced the differentiation of DPSCs to odonto-/osteoblastic fates by increasing the expression of the Alp, Dspp, Dmp1 and Bsp genes. Transplantation of the DPSC/PRF construct led both to a favorable regeneration of homogeneous and compact pulp-like tissues with abundantly distributed blood capillaries and to the deposition of regenerated dentin along the intracanal walls at 8 weeks post-operation. Thus, the application of DPSC/PRF tissue constructs might serve as a potential therapy in regenerative endodontics for pulp revitalization or revascularization.


Assuntos
Plaquetas/metabolismo , Polpa Dentária/irrigação sanguínea , Polpa Dentária/citologia , Fibrina/metabolismo , Transplante de Células-Tronco , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/metabolismo , Células Cultivadas , Cães , Humanos , Masculino , Camundongos Nus , Odontogênese , Osteogênese , Regeneração , Células-Tronco/metabolismo
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 22(4): 1022-6, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25130821

RESUMO

This study was aimed to explore the JAK2V617F mutation and TNF-α expression in patients with myeloproliferative neoplasm (MPN), and the relation between them so as to provide theoretical basis for clinical practice and target therapy. Sixty-two confirmed BCR-ABL-negative MPN patients and 15 healthy adults were enrolled in this study. The peripheral blood mononuclear cells of the patients and healthy controls were divided into two parts, one part was used to extract DNA, the other one was used to extract mRNA and reverse-transcribe into cDNA. Real-time fluorescent quantitative PCR was used to detect JAK2V617F mutation proportion and the expression level of TNF-α. The results showed that the positive rate of JAK2V617F mutation in MPN patients was 64.52% (40/62) , including 54.28% in essential thrombocythemia (ET) patients (19/35), 94.74% in polycythemia vera (PV) patients (18/19) and 37.50% in myelofibrosis (MF) (3/8) patients. Mutation proportions of JAK2V617F in ET, PV and MF patients were 0.838 ± 0.419, 4.417 ± 0.658, 2.746 ± 2.009 respectively. The expression of TNF-α in ET, PV and MF patients were higher than that in healthy controls: 1.7, 7.0, 8.2-fold (P < 0.05) respectively. In addition, TNF-α expression was correlated with JAK2V617F allele burden (Pearson r = 0.610,R(2) = 0.372,P = 0.005). It is concluded that TNF-α plays an important role in the pathogenesis of MPN, the TNF-α expression increases and is different in ET,PV and MF patients,which correlates with JAK2V617F allele burden.


Assuntos
Janus Quinase 2/genética , Transtornos Mieloproliferativos/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Adulto Jovem
19.
Artigo em Chinês | MEDLINE | ID: mdl-24820492

RESUMO

OBJECTIVE: To evaluate the effects of the application of tongue pressure sensor sheet on the signal waveform of laryngeal movement produced by the bend sensor during deglutition. METHODS: Twelve adult male subjects were recruited to perform a single swallow of 5 ml water when sitting on the dental chair with upright position. The data recorded by bend sensor was obtained with attaching tongue pressure sensor sheet simultaneously or not. Then the measured parameters by bend sensor with or without concurrent application of tongue pressure sensor sheet were compared. RESULTS: There were no significant differences between the same time point on the signal waveform produced by bend sensor whether concurrently attaching tongue pressure sensor sheet or not (P > 0.05). Additionally, we found no statistical significances between matched phases on the signal waveform recorded by bend sensor with or without application of tongue pressure sensor sheet (P > 0.05). CONCLUSION: The findings in this study suggest us that the usage of tongue pressure sensor sheet exerted no influences on the waveform of the laryngeal movement produced by bend sensor during deglutition, facilitating us to further apply tongue pressure sensor sheet and bend sensor simultaneously to record tongue pressure production and hyoid activity during deglutition.


Assuntos
Técnicas Biossensoriais/instrumentação , Deglutição/fisiologia , Laringe/fisiologia , Adulto , Humanos , Osso Hioide/fisiologia , Masculino , Pessoa de Meia-Idade , Pressão , Língua/fisiologia
20.
Monoclon Antib Immunodiagn Immunother ; 32(3): 216-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23750481

RESUMO

Trem-like transcript 2 (TLT-2), one of the TREM family members, which is expressed on B cells, T cells, and macrophages, plays a critical role in immune response mechanism. In this study, two novel mouse anti-human TLT-2 monoclonal antibodies (MAbs) were prepared using hybridoma technology and their immunological characteristics were determined. The results showed that the two MAbs (clones 10F5 and 8C10) were both IgG1 (κ) and bound specifically to human TLT-2. Furthermore, 10F5 and 8C10 seemed to recognize a different site (epitope) of TLT-2 by competition assay. MAb 10F5 was proven in Western blot analysis to specifically bind to denatured TLT-2 protein while both MAbs were proven in dot blot analyses and immunofluorescence to specifically bind to natural TLT-2 protein. In addition, crosslinking of TLT-2 with MAb 8C10 markedly blocked TLT-2 positive signal and T cell proliferation. Taken together, these two monoclonal antibodies might be of great value as tools for further exploration of the expression and function of TLT-2.


Assuntos
Anticorpos Monoclonais/imunologia , Receptores Imunológicos/imunologia , Linfócitos T/imunologia , Animais , Sítios de Ligação de Anticorpos/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Epitopos/imunologia , Humanos , Hibridomas/imunologia , Imunoglobulina G/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C
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