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1.
Oral Dis ; 23(1): 110-119, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27667507

RESUMO

OBJECTIVES: To determine the basic biochemical features of microparticles (MP) in patients with venous malformation (VM) of the head and neck. METHODS: Microparticles were isolated from peripheral venous blood of VM patients or healthy subjects and from lesional fluid of VM patients. Flow cytometry and real-time polymerase chain reaction were employed to determine the concentration, cellular origin, and RNA expression of obtained MP. A functional coagulation test was applied to measure the coagulant activity of MP. RESULTS: Circulating levels of total MP, platelet-derived MP, and endothelial MP were significantly elevated in VM patients and were consistently increased in VM patients with more extensive lesions. Lesional MP (MP from lesional fluid of VM) in VM patients were more abundant than circulating MP from VM patients or healthy subjects. Moreover, MP from VM patients displayed markedly distinct mRNA and microRNA expression compared with healthy subjects. Furthermore, MP from VM patients exhibited enhanced procoagulant activity, as evidenced by significantly shorter coagulation time. CONCLUSIONS: This study demonstrates for the first time that patients with VM have an altered MP profile and MP may be associated with VM-associated thrombogenesis. Further studies are required to explore the precise pathophysiological roles of MP in VM.


Assuntos
Micropartículas Derivadas de Células/química , Cabeça/irrigação sanguínea , Pescoço/irrigação sanguínea , Veias/anormalidades , Adulto , Idoso , Micropartículas Derivadas de Células/ultraestrutura , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
2.
Br J Dermatol ; 175(1): 102-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26873524

RESUMO

BACKGROUND: Lymphatic malformations (LMs), slow-flow vascular anomalies resulting from abnormal development of lymphatic channels, often progress rapidly after trauma or infection. OBJECTIVES: To explore the possible mechanism by which local infection promotes the progression of LMs. METHODS: Immunohistochemistry in serial sections and immunofluorescence were performed to label polarized macrophages. Tertiary lymphoid organs (TLOs) in LMs were identified using antibodies against CD3 (a T-cell marker), CD20 (a B-cell marker) and PNAd (a high endothelial venule marker). Pearson's correlation and cluster analysis were carried out to delineate the relationship between macrophage infiltration and TLO formation. Rat models of LM were established to examine the role of lipopolysaccharide in LM development. RESULTS: Compared with normal skin tissues, both M1- and M2-polarized macrophages were prevalent in LMs. Moreover, M2-polarized macrophages were significantly increased in infected LMs with an elevated density of TLOs. M2-polarized macrophages were observed in the centre of TLOs accompanied by intensive staining of macrophage colony-stimulating factor, a strong chemotactic factor for monocytes/macrophages, suggesting that macrophages might be recruited through TLOs. Cluster analysis and Pearson's correlation suggested a close relationship between macrophage infiltration and TLO formation. Furthermore, the expression of CD68 was also correlated with that of vascular endothelial growth factor (VEGF)-C and Ki67. Importantly, in an established LM rat model, lipopolysaccharide promoted the progression of the malformations with increased macrophage infiltration and TLO formation. CONCLUSIONS: M2-polarized macrophages that may be recruited through TLOs in infected LMs may contribute to the progression of the disease by secreting VEGF-C, and therefore accelerating the proliferation of lymphatic endothelial cells.


Assuntos
Infecções/imunologia , Vasos Linfáticos/anormalidades , Macrófagos/fisiologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Progressão da Doença , Células Endoteliais/imunologia , Células Endoteliais/fisiologia , Feminino , Lipopolissacarídeos/toxicidade , Macrófagos/imunologia , Macrófagos/metabolismo , Ratos Wistar , Fator C de Crescimento do Endotélio Vascular/metabolismo
3.
Br J Dermatol ; 171(2): 242-51, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24655310

RESUMO

BACKGROUND: Previous studies have implicated vascular destabilization and changes in extracellular matrix (ECM) composition in venous malformations (VMs). OBJECTIVES: To evaluate the expression levels of the connective tissue growth factor (CCN) family of matricellular proteins in VMs and explore their association with vascular destabilization. METHODS: The expression levels of CCNs 1-6, transforming growth factor (TGF)-ß, phosphorylated Tie2 and phosphorylated platelet-derived growth factor receptor ß in normal human skin tissues and VMs were detected by immunohistochemistry. Correlation between tested proteins was explored using the Spearman rank correlation test, followed by clustering analysis. In vitro studies using human umbilical vein endothelial cells (HUVECs) were performed for mechanism investigation. RESULTS: Expression of CCN2 was found to be strongly positive in fibroblast-like cells, endothelial cells and around blood vessels in normal human skin tissues, but it was significantly downregulated in VMs. Correlation analyses showed that expression levels of CCN2 and TGF-ß in VMs were positively correlated. The immunoreactivity of CCN2 was also closely correlated with perivascular α-smooth muscle cell actin(+) cell coverage in VMs. Moreover, in vitro studies in HUVECs indicated that CCN2 might act as a downstream target of TGF-ß, as demonstrated by the findings that treatment with exogenous TGF-ß or exogenous CCN2 could significantly upregulate the expression level of CCN2, and increase the expression levels of ECM components. Upregulation of the TGF-ß/CCN2 pathway was also detected in bleomycin-treated VM specimens. CONCLUSIONS: This study unmasks the downregulation of the TGF-ß/CCN2 pathway in VMs, and indicates its target potential for sclerotherapy.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Malformações Vasculares/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Regulação para Baixo/fisiologia , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Escleroterapia/métodos , Transdução de Sinais/fisiologia , Malformações Vasculares/terapia , Adulto Jovem
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(8): 760-765, 2024 Jul 22.
Artigo em Zh | MEDLINE | ID: mdl-39036905

RESUMO

The impaction rate of wisdom teeth is increasingly high, leading to more and more serious clinical problems. For a long time, the primary approach to managing wisdom teeth has been direct extraction, with a notable lack of systematic and diversified treatment methods. This article introduces, for the first time, the concept of whole life-cycle health management for wisdom teeth and suggests that the window for wisdom teeth life-cycle health management should be moved forward to the tooth germ stage. For tooth germs of wisdom teeth with severe risks, timely and necessary intervention should be administered. For normally erupting wisdom teeth, efforts should be made to maintain their health so they can function over the long term. For impacted wisdom teeth that have not caused related clinical symptoms, careful observation and cautious extraction should be considered. If necessary, techniques such as orthodontics and autotransplantation can be used to functionalize them. For impacted wisdom teeth that have caused clinical symptoms, functional oral surgical principles should be applied to reduce surgical trauma and prevent intraoperative and postoperative complications using advanced clinical techniques.

5.
J Dent Res ; 103(10): 988-998, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39101654

RESUMO

Most patients diagnosed with oral squamous cell carcinoma (OSCC) present with locally advanced stages, which are typically associated with poor outcomes. Although immunotherapy offers potential improvements in patient survival, its efficacy is hampered by low response rates. The microbiome is widely involved in tumor immunity and may play a role in immunotherapy. This study aimed to investigate the potential association between the oral (salivary) microbiome and immunotherapy response in patients with OSCC. Salivary metagenome sequencing was performed on 47 patients with OSCC undergoing neoadjuvant immunotherapy (NAIT) in a clinical trial (NCT04649476). Patients were divided into responders and nonresponders based on their pathological responses. The results showed that the species richness of the salivary microbiome was lower in the nonresponders before NAIT than in the responders. Differential analysis revealed that nonresponders exhibited a lower relative abundance of 34 bacterial species and a higher relative abundance of 4 bacterial species. Notably, low levels of Eubacterium infirmum, Actinobaculum, and Selenomas (EAS) in the saliva may be associated with the nonresponse of patients with OSCC to NAIT. A nomogram based on EAS was developed and validated to determine the efficacy of NAIT. The area under the curve for the training cohort was 0.81 (95% confidence interval, 0.66 to 0.81). Quantitative polymerase chain reaction confirmed that low levels of salivary EAS effectively identified nonresponders to NAIT. Furthermore, the low abundance of salivary EAS was closely correlated with a low density of intratumoral CD4+, CD14+, CD68+, and FOXP3+ cells. Metabolic functional annotation revealed numerous biosynthetic processes associated with EAS that were more active in responders. In summary, this study provides valuable data resources for the salivary microbiome and reveals that nonresponders have different salivary microbiome profiles than responders do before NAIT. Low salivary EAS levels can serve as potential biomarkers for distinguishing nonresponders from responders.


Assuntos
Carcinoma de Células Escamosas , Imunoterapia , Microbiota , Neoplasias Bucais , Terapia Neoadjuvante , Saliva , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/microbiologia , Imunoterapia/métodos , Neoplasias Bucais/terapia , Neoplasias Bucais/microbiologia , Neoplasias Bucais/imunologia , Saliva/microbiologia , Saliva/imunologia , Resultado do Tratamento
6.
Eur Rev Med Pharmacol Sci ; 27(24): 11755-11763, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38164838

RESUMO

OBJECTIVE: We aimed to investigate the effects of methoxamine to prevent hypotension in the elderly with intraspinal anesthesia (IA) on myocardial injury and cardiac function. PATIENTS AND METHODS: A retrospective study was conducted by enrolling sixty elderly patients who underwent femoral head replacement (FHR) under IA in our hospital from August 2019 to August 2020. The patients were divided into two groups according to the random number table method. In the control group (CG) (30 patients), 5 mg of ephedrine was administered sedately when patients developed hypotension (20% below basal blood pressure). In the research group (RG) (30 cases), 2 µg/(kg·h) of methoxamine hydrochloride was given as a constant-rate pump before anesthesia, and 1 mg of methoxamine hydrochloride was administered intraoperatively if hypotension occurred. The hemodynamic [systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR)], myocardial injury indexes [cardiac troponin I (cTnI), creatine kinase isoenzyme MB (CK-MB), fatty acid binding protein (FABP), plasma amino-terminal brain natriuretic peptide precursor (NT-proBNP)], cardiac function indexes [systemic vascular resistance (SVR), stroke volume (SV), net percentage ejection time (ET)] were observed before anesthesia (T1), at the end of surgery (T2), and 6 h after surgery (T3) in both groups. The Bruggemann Comfort Score (BCS) and Visual Analog Scale (VAS) scores at T3, 12 h postoperatively (T4) and 24 h postoperatively (T5) in both groups were observed, and the incidence of adverse reactions to intralesional anesthesia in both groups was counted. RESULTS: SBP, DBP and HR at T2 were lower than those at T1 in both groups, and SBP, DBP and HR at T3 were higher than those at T2, and SBP, DBP and HR at T2 and T3 in the RG were higher than those in the CG (p<0.05). In both groups, cTnⅠ, CK-MB and FABP were higher at T2 and T3 than at T1, higher at T3 than at T2, and NT-proBNP was higher at T2 than at T1 and T3, and lower in the RG than in the CG (p<0.05). In both groups, SVR and SV at time point T2 were lower than at time point T1 and ET was higher than at time point T1, SVR and SV at time point T3 were higher than at time point T2 and ET was lower than at time point T2, SVR and SV in the RG were higher than in the CG and ET was lower than in the CG (p<0.05). VAS scores were higher in both groups at T4 and T5 than at T3, and lower in the RG than in the CG (p<0.05). CONCLUSIONS: Methoxamine can effectively reduce the risk of hypotension in geriatric endotracheal anesthesia, which can reduce myocardial injury and stabilize cardiac function in patients.


Assuntos
Anestesia , Hipotensão , Humanos , Idoso , Metoxamina , Estudos Retrospectivos , Hemodinâmica , Creatina Quinase Forma MB , Proteínas de Ligação a Ácido Graxo , Hipotensão/induzido quimicamente , Hipotensão/tratamento farmacológico , Hipotensão/prevenção & controle
7.
J Appl Microbiol ; 112(1): 38-44, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21985089

RESUMO

AIMS: Developing an innovative process for ethanol fermentation from Jerusalem artichoke tubers under very high gravity (VHG) conditions. METHODS AND RESULTS: A consolidated bioprocessing (CBP) strategy that integrated inulinase production, saccharification of inulin contained in Jerusalem artichoke tubers and ethanol production from sugars released from inulin by the enzyme was developed with the inulinase-producing yeast Kluyveromyces marxianus Y179 and fed-batch operation. The impact of inoculum age, aeration, the supplementation of pectinase and nutrients on the ethanol fermentation performance of the CBP system was studied. Although inulinase activities increased with the extension of the seed incubation time, its contribution to ethanol production was negligible because vigorously growing yeast cells harvested earlier carried out ethanol fermentation more efficiently. Thus, the overnight incubation that has been practised in ethanol production from starch-based feedstocks is recommended. Aeration facilitated the fermentation process, but compromised ethanol yield because of the negative Crabtree effect of the species, and increases the risk of contamination under industrial conditions. Therefore, nonaeration conditions are preferred for the CBP system. Pectinase supplementation reduced viscosity of the fermentation broth and improved ethanol production performance, particularly under high gravity conditions, but the enzyme cost should be carefully balanced. Medium optimization was performed, and ethanol concentration as high as 94·2 g l(-1) was achieved when 0·15 g l(-1) K(2) HPO(4) was supplemented, which presents a significant progress in ethanol production from Jerusalem artichoke tubers. CONCLUSIONS: A CBP system using K. marxianus is suitable for efficient ethanol production from Jerusalem artichoke tubers under VHG conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Jerusalem artichoke tubers are an alternative to grain-based feedstocks for ethanol production. The high ethanol concentration achieved using K. marxianus with the CBP system not only saves energy consumption for ethanol distillation, but also significantly reduces the amount of waste distillage discharged from the distillation system.


Assuntos
Biotecnologia/métodos , Etanol/metabolismo , Helianthus/metabolismo , Hipergravidade , Kluyveromyces/metabolismo , Aerobiose , Fermentação , Glicosídeo Hidrolases/metabolismo , Inulina/metabolismo , Kluyveromyces/enzimologia , Poligalacturonase/metabolismo , Fatores de Tempo , Viscosidade
8.
BMJ Open ; 12(3): e059067, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338068

RESUMO

INTRODUCTION: COVID-19 is a public health emergency of international concern, which is characterised by rapid and widespread transmission, high mortality and complications. Several studies have shown the benefits of tai chi and qigong for recovery after COVID-19; however, no meta-analysis has been reported. Therefore, the purpose of this study is to evaluate the efficacy and safety of tai chi and/or qigong on rehabilitation after COVID-19 through a systematic review and meta-analysis to provide a reference and basis for clinical application. METHODS AND ANALYSIS: This study will use the Cochrane Library, PubMed, Web of Science, Embase, China Knowledge Network, China Biomedical Literature Database, Chinese Scientific Journal Database and Wanfang Database. The time period is from the inception of the database to November 2021, with no language restrictions. Searches will be conducted using the subject terms "Taichi","Qigong" and "COVID-19" plus free-text words. Articles will be screened and collected by two reviewers independently. Included studies will be assessed for quality using the Cochrane Risk of Bias Assessment Tool. Statistical analyses will be performed using the Revman V.5.3 software. The primary outcomes include 1-second forced expiratory volume and 1-second forced vital capacity, oxygen saturation, total white cell count and quality of life score. Secondary outcomes include time to remission of major symptoms, incidence of adverse events, clinical cure rate and mortality. Subgroup and sensitivity analyses will also be used to explore and interpret the heterogeneity. This protocol is written based on the guideline of the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocol. ETHICS AND DISSEMINATION: Ethical approval and consent are unnecessary because no primary data will be collected. The results will be disseminated through peer-reviewed publications. PROSPERO REGISTRATION NUMBER: CRD42021288962.


Assuntos
COVID-19 , Qigong , Tai Chi Chuan , Humanos , Metanálise como Assunto , Qualidade de Vida , Revisões Sistemáticas como Assunto
9.
J Dent Res ; 96(13): 1546-1554, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28732179

RESUMO

Oral epithelial adhesion to the lamina propria underlies the physiologic function of the oral mucosa and contributes to resisting bacterial invasion, preventing body fluid loss, and maintaining routine chewing; thus, understanding the factors that positively influence oral epithelial adhesion is a research topic of great interest. Rete pegs contribute to oral epithelial adhesion by enlarging the contact areas, whereas integrins are the major molecules that mediate epithelial cell adhesion to the basement membrane. Keratinocyte growth factor (KGF) can promote both rete peg elongation in the skin and the expression of integrins in various cell types. Herein, we tested the effects of submucosal injection of KGF in the ventral surfaces of rat tongues on oral epithelial adhesion. The data confirmed that topical injection of KGF elevated the adhesive forces, elongated the rete pegs, and increased the abundance of integrins, KGF, and KGF receptor on the rat tongue ventral surface. However, HYD-1 (Lys-Ile-Lys-Met-Val-Ile-Ser-Trp-Lys-Gly), an integrin antagonist, inhibited the KGF-enhanced epithelial adhesion and rete peg elongation. Moreover, KGF promoted the expression of integrin subunits α6, ß4, α3, and ß1 in human immortalized oral epithelial cells in 2- and 3-dimensional culture systems. In vitro cell attachment assays demonstrated that HYD-1 inhibited the adhesion of human immortalized oral epithelial cells on Matrigel. Strikingly, the expression of integrins, KGF, and KGFR in human masticatory mucosae with longer rete pegs was more abundant than that in the lining mucosae with shorter rete pegs. In addition, rete peg lengths were positively correlated with the expression levels of integrins, KGF, and KGF receptor. These findings indicate that KGF strengthens oral epithelial adhesion and rete peg elongation via integrins.


Assuntos
Adesão Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fator 7 de Crescimento de Fibroblastos/farmacologia , Integrinas/metabolismo , Mucosa Bucal/citologia , Animais , Western Blotting , Técnicas de Cultura de Células , Fator 7 de Crescimento de Fibroblastos/metabolismo , Masculino , Oligopeptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
10.
J Dent Res ; 95(8): 860-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27013642

RESUMO

Our recent study established the increased circulating microparticles (MPs) and their procoagulant activity in oral squamous cell carcinoma (OSCC). In the present study, we further evaluated different phenotypes of circulating MPs in OSCC patients and explored their clinical significance and effects on angiogenesis (a critical event in tumor progression). To conduct the study, circulating MPs in 45 OSCC patients and 18 healthy volunteers were characterized and quantified by transmission electron microscopy and flow cytometry. Correlations between circulating MPs and clinicopathologic data, microvessel density, and proangiogenic factor levels in patients with OSCC were analyzed by immunohistochemistry and Spearman rank correlation test. Additionally, the in vitro studies were performed with use of human umbilical vein endothelial cells. Our results showed that the levels of circulating MPs as well as the subsets of platelet-derived, endothelium-derived, and pan-leukocyte MPs in stages III to IV OSCC were significantly higher than stages I to II and healthy subjects. Moreover, these increased circulating MPs were significantly correlated with tumor size, TNM stages, microvessel density, and expression levels of vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP9) in OSCC patients. The in vitro studies revealed that circulating MPs isolated from OSCC patients could be effectively taken up by human umbilical vein endothelial cells and could promote the proliferation, migration, invasion, and tube formation of recipient endothelial cells, accompanied by increased expression of proangiogenic factors. In summary, circulating MPs play important roles in angiogenesis and local tumor progression of OSCC. Our results shed new light on the progression of OSCC and might be helpful to explore novel treatment strategies targeting tumor angiogenesis.


Assuntos
Carcinoma de Células Escamosas/patologia , Micropartículas Derivadas de Células/patologia , Neoplasias Bucais/patologia , Neovascularização Patológica/patologia , Estudos de Casos e Controles , Movimento Celular , Células Cultivadas , Células Endoteliais/patologia , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Microscopia Eletrônica de Transmissão , Invasividade Neoplásica , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Dent Res ; 95(1): 87-93, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26124218

RESUMO

Numerous studies have demonstrated that circulating microparticles (MPs) play important roles in a variety of diseases (e.g., atherosclerosis, hypertension, and diabetes), but the association between circulating MPs and oral squamous cell carcinoma (OSCC) remains largely unknown. In the present study, the circulating platelet-derived MPs (PMPs) in 63 patients with OSCC, 22 patients with infected keratocystic odontogenic tumor, and 31 healthy volunteers were characterized and quantified by flow cytometric analysis. The coagulation function of patients with OSCC was correspondingly evaluated. Meanwhile, the inflammation-related cytokines were detected in plasma by enzyme-linked immunosorbent assay and in tumor tissues by immunohistochemistry. Our results showed that the plasma level of circulating PMPs was significantly higher in OSCC patients compared with healthy volunteers and patients with infected keratocystic odontogenic tumor, and they showed positive correlation with the increased level of fibrinogen. Moreover, the coagulation time was significantly shorter after the MPs were added to the MP-free plasma. Most important, the levels of interleukin 6 and tumor necrosis factor α in plasma and tumor tissues were significantly increased in OSCC patients, which were closely correlated with the elevated level of circulating PMPs. In summary, this study suggests that the elevated level of circulating PMPs, showing close correlation with the secretion of inflammation-related factors, may contribute to the increased procoagulant activity in patients with OSCC.


Assuntos
Plaquetas/patologia , Carcinoma de Células Escamosas/patologia , Micropartículas Derivadas de Células/patologia , Neoplasias Bucais/patologia , Coagulação Sanguínea/fisiologia , Plaquetas/química , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/química , Micropartículas Derivadas de Células/química , Citocinas/análise , Citocinas/sangue , Feminino , Fibrinogênio/análise , Citometria de Fluxo/métodos , Humanos , Interleucina-6/análise , Interleucina-6/sangue , Masculino , Neoplasias Bucais/sangue , Neoplasias Bucais/química , Estadiamento de Neoplasias , Tumores Odontogênicos/patologia , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/sangue
12.
FEBS Lett ; 488(3): 123-32, 2001 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-11163758

RESUMO

Reactive oxygen species (ROS) have been found to trigger apoptosis in tumor cells. At the same time, telomerase is found to be associated with malignancy and reduced apoptosis. However little is known about the linkage between ROS such as *OH and telomerase/telomere. To address the interrelations between *OH and telomerase/telomere in tumor cell killing, HeLa, 293 and MW451 cells were induced to undergo apoptosis with *OH radicals generated via Fe(2+)-mediated Fenton reactions (0.1 mM FeSO(4) plus 0.3-0.9 mM H2O2) and telomerase activity, telomere length were measured during apoptosis. We found that during *OH-induced apoptosis, telomere shortening took place while no changes in telomerase activity were observed. Our results suggest that *OH-induced telomere shortening is not through telomerase inhibition but possibly a direct effect of *OH on telomeres themselves indicating that telomere shortening but not telomerase inhibition is the primary event during *OH-induced apoptosis. Strikingly, we also found that *OH-induced apoptosis in HeLa cells is caspase-3-independent but is associated with reduction of mitochondrial transmembrane potential. Our results indicate that *OH triggers apoptotic tumor cell death through a telomere-related, caspase-independent pathway.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Radical Hidroxila/farmacologia , Telomerase/metabolismo , Telômero/efeitos dos fármacos , Telômero/metabolismo , Caspase 3 , Inibidores de Caspase , Linhagem Celular , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Glutationa/metabolismo , Glutationa/farmacologia , Células HeLa , Humanos , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Marcação In Situ das Extremidades Cortadas , Potenciais da Membrana/efeitos dos fármacos , Microscopia Eletrônica , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Telomerase/antagonistas & inibidores , Telômero/química , Telômero/ultraestrutura
13.
FEBS Lett ; 488(3): 133-8, 2001 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-11163759

RESUMO

In tumor cells telomerase activity is associated with resistance to apoptosis and the introduction of the human telomerase reverse transcriptase (hTERT) subunit into normal human cells is associated with life span extension of the cells. To determine the role of telomerase in regulating apoptosis, telomerase negative human embryo lung fibroblasts were transfected with the hTERT gene. Unlike the control fibroblasts, the telomerase-expressing cells had elongated telomeres and were resistant to apoptosis induced by hydroxyl radicals. The results indicate that expression of telomerase and, thus, the maintenance of telomere length in normal human somatic cells caused resistance to not only cellular senescence but also apoptosis. Moreover, we found that hydroxyl radical-induced apoptosis in telomerase-expressing and control fibroblasts was caspase-3 independent. These findings have revealed a new type of interrelation between telomerase and caspase-3, which may indicate that in this case the expressed telomerase may inhibit apoptosis at a site not related to the caspase-3 cascade.


Assuntos
Apoptose , Fibroblastos/metabolismo , Deleção de Genes , Radical Hidroxila/antagonistas & inibidores , Telomerase/metabolismo , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Células Clonais/enzimologia , Células Clonais/metabolismo , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Humanos , Radical Hidroxila/farmacologia , Pulmão , Telomerase/genética , Telômero/química , Telômero/genética , Telômero/metabolismo , Transfecção
14.
Artigo em Zh | MEDLINE | ID: mdl-12572063

RESUMO

OBJECTIVE: To develop 23 kDa membrane protein DNA vaccine of Schistosoma japonicum Chinese strain and test its protective efficacy in infected C57BL/6 mice. METHODS: The full length cDNA encoding SjC23 amplified from pUC19-SjC23 subcloned into pcDNA3.1. 48 female mice were divided into three groups: A, B and C. Group A (control group) was each immunized i.m. with 100 micrograms of pcDNA3.1; group B (SjC23 group) was each immunized i.m. with 100 micrograms of pcDNA3.1-SjC23; group C (SjC23 + IL-12) was each immunized i.m. with a mixture of 100 micrograms of pcDNA3.1-SjC23, 100 micrograms of pcDNA3.1-p35 and 100 micrograms of pcDNA-p40, followed by two boosts of the same DNA once every two weeks. All the mice were challenged with 45 cercariae at week 8, killed and perfused for worms at week 14. The expression of SjC23 and p35, p40 in muscle tissue was determined by immuno-histochemical method. By the culture of spleen cells, the production of IL-2, IL-4, IL-10 and IFN-gamma after the stimulation of rSjC23-HD was determined two weeks before and after challenge. Anti-SjC23 antibodies were tested by Western blotting. RESULTS: SjC23 and p35, p40 were all expressed on the membrane and in the plasma of muscle cells of the infected mice. Significant increase of IL-2 and IFN-gamma in SjC23 and SjC23 + IL-12 groups was observed before and after challenge. Western blotting showed that after the third immunization (before challenge) 8 out of 10 sera from SjC23 group and 9 out of 10 sera from SjC23 + IL-12 group were positive. The worm reduction rate in SjC23 group and SjC23 + IL-12 group was 26.9% and 35.4%, respectively; the number of eggs in liver tissue was reduced by 22.2% and 28.4%, respectively. CONCLUSION: pcDNA3.1-SjC23 DNA vaccine could induce partial protection against Schistosoma japonicum in C57BL/6 mice.


Assuntos
Antígenos de Helmintos/imunologia , Proteínas de Helminto/imunologia , Proteínas de Membrana/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/prevenção & controle , Vacinas de DNA/imunologia , Animais , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Esquistossomose Japônica/imunologia , Baço/imunologia , Baço/metabolismo
15.
Shi Yan Sheng Wu Xue Bao ; 31(3): 273-82, 1998 Sep.
Artigo em Zh | MEDLINE | ID: mdl-12016972

RESUMO

The human hepatoma cells SMMC-7721 were treated with different concentrations of ascorbic acid (50-800 mumol/L) and FeSO4 (2.5-40 mumol/L) system to generate oxidative stress at various degrees. The oxidative stress induced by the system were mainly contributed to hydroxyl radical. All the various degrees of oxidative stress in this study are able to inhibit the proliferation of hepatoma cells. While low levels of oxidative stress may cause hepatoma cells lost some malignant features, such as aggregation of Con-A to the cell surface, alpha-fetoprotein, gamma-glutamyltransepeptidase and tyrosine-alpha-ketoglutarate transaminase, all of the 4 indices tended to cell differentiation, coloning efficiency potential decreased significantly, and apoptotic cells appeared. The numbers of apoptotic cells increased with the increasing of oxidative stress. The apoptotic cells exhibited non-adherent, smaller, chromatin condensed around the periphery of the nucleus in the shape of crescent, nuclear fragmentations but with intact cellular membrane, and DNA degraded to around 21.2 kbp fragment. All of the results showed that there is possibility to inhibit hepatoma cells growth, to promote differentiation and apoptosis, and therefore to initiate reverse transformation via strict regulation of oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Neoplasias Hepáticas/patologia , Estresse Oxidativo , Divisão Celular/efeitos dos fármacos , Humanos , Células Tumorais Cultivadas
16.
Cell Biol Int ; 22(1): 41-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9828081

RESUMO

The effects of oxidative stress (ascorbic acid-ferrous system) on the proliferation, differentiation and apoptosis of the human hepatoma cell SMMC-7721 were studied. Oxidative stress significantly inhibited cell proliferation and induced morphological differentiation. Whatever the indices related with cell malignancy, such as alpha-fetoprotein and c-glutamyltranspeptidase or the index related with cell differentiation, such as tyrosine-alpha-ketoglutarate transaminase, all inclined evidently to normalization. The tumour's clonogenic potential decreased significantly. Moreover, together with differentiation, the phenomenon of apoptosis was found by the appearance of apoptotic bodies, detached cells, and apoptotic morphological feature. Although, their DNA was not degraded into oligonucleosomal fragmentation, the DNA was cut into larger fragments (about 21.2 kbp) of a size associated with chromatin loops. These findings indicated that oxidative stress can induce both differentiation and apoptosis simultaneously in tumour cells. All the results showed that oxidative stress may initiate the tumour cells reverse transformation. The possible mechanism of the differentiation and apoptosis induced by oxidative stress may be related to the lipid peroxidation of cell membrane.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Estresse Oxidativo/fisiologia , Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Fragmentação do DNA/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Glutationa/metabolismo , Humanos , Ferro/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Lipídeos de Membrana/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Células Tumorais Cultivadas
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