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1.
Polymers (Basel) ; 13(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557362

RESUMO

The ability of long-term thermo-oxidative resistance is very important for elastomers in application. However, many conventional antioxidants are difficult to realize the long-term thermo-oxidative resistance. To overcome this limitation, a design strategy is introduced by combing elastomers with MXene and natural rubber (NR) is chosen as a model material. MXene is efficient in absorbing oxygen and the generated free radicals in the NR matrix and can inhibit the diffusion of oxygen toward the interior. Moreover, MXene, like graphene and carbon black, absorbs molecular chains, inhibiting the migration of MXene toward the surface of the sample. Such characteristics of MXene endow NR/MXene with the long-term outstanding thermo-oxidative resistance. For example, after three days of the thermo-oxidative process for NR/MXene, the tensile strength is 19 MPa and the retention of tensile strength is 63%, which far exceeds the effects of conventional antioxidants. This work not only provides a good guide for the universal design of elastomers with long-term thermo-oxidative resistance but also expands the application of MXene.

2.
J Nanosci Nanotechnol ; 21(4): 2196-2202, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33500034

RESUMO

ZrC was produced by the combustion synthesis technology using Cu, Zr, and graphite as the starting element powders. The synthesis mechanism of ZrC was investigated by the combustion wave quenching experiment. Furthermore, the effects of sizes of C and Cu on the combustion synthesis behavior and products were also explored. Results revealed that ZrC was fabricated through the displacement reaction between C and Cu-Zr liquid. The Cu size hardly affected the combustion temperature and resultant products, indicating that the preparation cost of ZrC could be decreased by employing coarse Cu powders. With increasing C size, the burning temperature and ceramic particle size reduced. Graphite with size of 2.6 µm was used as the C source, and only ZrC nanoparticles and Cu were obtained. The products could be employed to prepare nano-sized ZrC/Cu composites without the elimination of by-products.

3.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1233-1240, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530198

RESUMO

Grassland is an important type of terrestrial ecosystem. Using remote sensing technology to study the change and driving force of native grassland productivity at large scale is an important way to understand the ecological status of grassland. In this study, potential and actual net primary productivity (NPP) of Xilingol steppe from 2000 to 2018 were examined based on climatic model and light-use efficiency model, respectively. NPP damage value driven by human activities was calculated from the difference between potential and actual NPP. The least square method was used to analyze the temporal and spatial variation of NPP in Xilingol and the driving role of climate and human activities on NPP. The results showed that NPP in Xilingol increased from west to east, with mean annual NPP being 271.54 g C·m-2·a-1, the area with increased NPP (grassland restoration) being 36500 km2, and the area with decreased NPP (grassland degradation) being 59900 km2. The potential NPP tended to rise under the driving force of temperature and precipitation, with an average annual increase of 6.5 g C·m-2·a-1, which indicated that regional climate played a positive role in the improvement of NPP in Xilingol steppe, and that human activities were the main driving force for grassland degradation. The value of NPP damage driven by human activities decreased from east to west and from south to north, with the highest value in Wuzhumuqin meadow and southern steppe. Human activities, such as mining and reclamation, had the most obvious negative impact on grassland NPP.


Assuntos
Ecossistema , Pradaria , China , Mudança Climática , Atividades Humanas , Humanos , Modelos Teóricos , Tecnologia de Sensoriamento Remoto
4.
ACS Appl Mater Interfaces ; 12(12): 14468-14475, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32129596

RESUMO

Mechanical strength and toughness are usually mutually exclusive, but they can both appear in natural rubber (NR). Previous studies ascribe such excellent properties to highly cis stereoregularity of NR. To our surprise, after the removal of non-rubber components (NRC) by centrifugation, the strength and toughness of NR decrease dramatically. It is still a challenge for us to make out for the problem of how NRC affect the properties of NR. Our group ascribes the superior mechanical robustness of NR to NRC. To further verify such a viewpoint, we add phospholipids (phosphatidylcholines) into NR without NRC. Phosphatidylcholines construct a sacrificial network, which ruptures preferentially upon deformation to dissipate energy. Moreover, some of phosphatidylcholines participate in the vulcanization reaction, which further improves the mechanical strength and energy dissipation. As a result, the mechanical strength and toughness of samples are as high as 21.1 MPa and 49.6 kJ/m2, respectively, which have reached the same level as that of NR. Therefore, this work not only imitates the excellent mechanical robustness of NR but also further provides a rational design for elastomers with excellent mechanical robustness.


Assuntos
Fenômenos Mecânicos , Fosfolipídeos/química , Borracha/química , Butadienos/química , Elastômeros/química
5.
Int J Ophthalmol ; 12(1): 30-37, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30662837

RESUMO

AIM: To illustrate the isoform-specific role and mechanism of c-Jun N-terminal kinases (JNKs) in mouse optic nerve axotomy induced neurotrauma. METHODS: We firstly investigated the expression of JNK1, JNK2, and JNK3 in the retinal ganglion cells (RGCs) by double-immunofluorescent staining. Then we created optic nerve axotomy model in wild type as well as JNK1, JNK2, JNK3, isoform specific gene deficiency mice. With that, we checked the protein expression profile of JNKs and its active form, and quantified the survival RGCs number by immunofluorescence staining. We further explored the molecules underlying isoform specific protective effect by real-time polymerase chain reaction (PCR) and Western blotting assay. RESULTS: We found that all the three isoforms of JNKs were expressed in the RGCs. Deficiency of JNK3, but not JNK1 or JNK2, significantly alleviated optic nerve axotomy induced RGCs apoptosis. We further established that expression of Noxa, a pro-apoptotic member of BH3 family, was significantly suppressed only in JNK3 gene deficiency mice. But tumor necrosis factor receptor 1 (TNFR1) and Fas, two key modulators of death receptor mediated apoptosis pathway, did not display obvious change in the expression. CONCLUSION: It is suggested that mitochondria mediated apoptosis, but not death receptor mediated apoptosis got involved in the JNK3 gene deficiency induced RGCs protection. Our study provides a novel insight into the isoform-specific role of JNKs in neurotrauma and indicates some cues for its therapeutics.

6.
J Cancer Res Ther ; 10 Suppl: C108-13, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25450267

RESUMO

OBJECTIVES: The aim of this study was to examine the growth arrest and DNA damage-inducible (Gadd45a) expression and its role in tumor progression, invasion and metastasis in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Growth arrest and DNA damage-inducible 45a distribution was detected by immunohistochemistry in tumor sections of 106 patients with primary OSCC and sections of adjacent pericancerous tissues from 60 patients among the 106. The association between the Gadd45a expression and clinical prognosis of OSCC were performed by statistical analysis. Gadd45a gene knockdown was performed in Tca8113 cells by small interfering ribonucleic acid treatment and its effects on cell cycle, and migration were detected by Flow Cytometric (Becton Dickinson, USA) and transwell chamber assay respectively. RESULTS AND CONCLUSION: The results showed that Gadd45a was redistributed to cytoplasm in poorly differentiated carcinoma from its nucleus location in normal tissue (P < 0.05). The expression of Gadd45a was significantly associated with lymph node metastasis, tumor stage and tumor histological grade (P < 0.05). Knockdown of Gadd45a gene abolished the G2/M arrest and increased migrating ability of Tca8113 cell (P < 0.05). The results indicate that Gadd45a play an important role in OSCC metastasis by affecting the bioactivity of the tumor cells, and its distribution may serve for the prediction of clinical outcome of OSCC.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Proteínas Nucleares/genética , Pontos de Checagem do Ciclo Celular/genética , Movimento Celular/genética , Dano ao DNA/genética , Progressão da Doença , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Humanos , Metástase Linfática/genética , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , RNA Interferente Pequeno/genética
7.
Zhonghua Yan Ke Za Zhi ; 48(9): 794-8, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23141573

RESUMO

OBJECTIVE: To study the changes of fibronectin in the resected medial rectus muscles in patients with concomitant exotropia and to have a better understanding about the pathomorphological changes of extraocular muscles in the genesis and development of concomitant exotropia. METHODS: Thirty-five concomitant exotropic patients were chosen as exotropic group and 20 normals were selected as control group. In the exotropic group, the age range 2 to 46 years old (mean, 20.9 ys), deviation range -45(Δ) to -90(Δ) (mean, -67.5(Δ)), 19 males, 16 females, and 8 cases have the family history. Exotropic patients were divided into intermittent exotropic group 16 cases and constant exotropic group 19 cases. In the control group, the age range 15 - 28 years old (mean, 18.8 years), 12 males and 8 females. All the resected tissues of the medial rectus muscles were obtained from patients with concomitant exotropia during resection surgery and cornea donators. Fibronectin was measured its mean average optical by Sp method of immunohistochemistry using image analyzer. The amounts of fibronectin in the resected muscle of patients were compared with normals, as well as correlated clinical data of patients such as different types of exotropia, age, degree of deviation, gender and positive family history. RESULTS: The amounts of fibronectin in the resected medial rectus muscle of patients with constant exotropia (0.4729 ± 0.0872) were significantly lower than those of normals (0.5914 ± 0.0547) and intermittent exotropic group (0.5821 ± 0.0792) respectively (q = 7.0314, 6.1177, P < 0.01), while patients with intermittent exotropia did not show significantly lower amounts of fibronectin than those with normals (q = 0.5271, P > 0.05). Neither gender nor positive family was correlated with the amounts of fibronectin (t = 1.1317, 1.6327, P > 0.05) and the amounts of fibronectin had no correlation with age and degree of deviation. CONCLUSION: The amounts of fibronectin were correlated with the course of development of concomitant exotropia. Some of these changes may play a role in the pathogenesis of exotropia from intermittence to constancy, which indicates a further clue to the nature of this disease.


Assuntos
Exotropia/metabolismo , Fibronectinas/metabolismo , Músculos Oculomotores/metabolismo , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Exotropia/patologia , Exotropia/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Clin Immunol ; 31(5): 827-39, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21671129

RESUMO

Oral lichen planus is a chronic inflammatory disorder of the oral mucosa that represents T cell-mediated autoimmune diseases. The regulation and roles of carcinoembryonic antigen-related cellular adhesion molecule 1 (CEACAM1), a novel immune molecule, in the immunopathogenesis of T cell-mediated autoimmune diseases remain unclear. In the current paper, CEACAM1 was found to be overexpressed in peripheral T cells and epithelial cells in oral lichen planus patients. A fraction of infiltrating inflammatory mononuclear cells in the lamina propria of the oral lichen planus mucosa also expressed CEACAM1. Importantly, for the first time, CEACAM1 expression in T cells and in normal human oral keratinocytes was demonstrated to be regulated differently by osteopontin in vitro. Furthermore, the apoptosis of oral keratinocytes and activated T cells can be markedly suppressed by CEACAM1-specific monoclonal antibodies. In conclusion, OPN-regulated CEACAM1 expression may play a critical role in the immunopathogenesis of oral lichen planus.


Assuntos
Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Queratinócitos/metabolismo , Líquen Plano Bucal/imunologia , Mucosa Bucal/patologia , Linfócitos T/metabolismo , Adulto , Anticorpos Bloqueadores/farmacologia , Antígenos CD/genética , Antígenos CD/imunologia , Apoptose/efeitos dos fármacos , Autoimunidade , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Queratinócitos/patologia , Líquen Plano Bucal/patologia , Líquen Plano Bucal/fisiopatologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Osteopontina/imunologia , Osteopontina/farmacologia , Estomatite , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/patologia
9.
Acta Pharmacol Sin ; 32(2): 253-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21293478

RESUMO

AIM: To investigate the effect of the growth arrest- and DNA damage-inducible Gadd45a gene on the radiosensitivity of human tongue squamous cell carcinoma cell line to ionizing radiation (IR). METHODS: Short interfering ribonucleic acid (si-RNA) targeting Gadd45a or an irrelevant mRNA (nonsense si-RNA) was chemically synthesized. The constructed si-RNAs were transfected into Tca8113 cells and Gadd45a expression was determined using quantitative real-time PCR and Western-blot. After 24-h exposure to IR at a dose rate of 4 Gy/min, apoptosis of Tca8113 cells was detected using flow cytometry, and radiosensitivity was measured using MTT assays. RESULTS: IR apparently increased the expression of Gadd45a at mRNA and protein levels in Tca8113 cells. The effect was efficiently inhibited by transfection with Gadd45a si-RNA (P<0.01). Furthermore, silencing Gadd45a gene significantly increased cell viability and decreased the percentage of apoptotic cells during irradiation, which indicated that IR-induced Gadd45a over-expression could increase the radiosensitivity of Tca8113 cells. CONCLUSION: These results indicated that targeting Gadd45a may have important therapeutic implications in sensitizing Tca8113 cells to IR.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/genética , Neoplasias da Língua/radioterapia , Apoptose/genética , Apoptose/efeitos da radiação , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Inativação Gênica , Humanos , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Radiação Ionizante , Neoplasias da Língua/genética , Neoplasias da Língua/patologia , Transfecção
10.
Clin Immunol ; 138(3): 291-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21215700

RESUMO

Oral lichen planus (OLP) is a chronic inflammatory disorder of oral mucosa, which represents cell-mediated autoimmune diseases. Pathological study demonstrated that abundant T lymphocytes infiltrated the oral mucosa, in which the activated T cells that trigger apoptosis of oral epithelial cells is an important mechanism for OLP. However, to date the molecular mechanisms underlying the T lymphocytes infiltration and accumulation in OLP remain unclear. In this paper, we found that the levels of plasma OPN were elevated and were associated with the up-regulated expressions of CD44 in OLP patients. In vitro, the addition of exogenous OPN can suppress the apoptosis of activated CD8(+) T cells via CD44, and this T cell resistance to apoptosis may be attributed to the reduction of endogenous mature granzyme B. Our results suggested that the abnormally elevated levels of OPN may contribute to the abnormal infiltration and accumulation of the activated T cells by up-regulating CD44 in OLP.


Assuntos
Receptores de Hialuronatos/imunologia , Líquen Plano Bucal/imunologia , Regulação para Cima/imunologia , Apoptose/imunologia , Complexo CD3/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Sobrevivência Celular , Granzimas/imunologia , Granzimas/metabolismo , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Líquen Plano Bucal/sangue , Líquen Plano Bucal/metabolismo , Líquen Plano Bucal/patologia , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 28(2): 158-61, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20480658

RESUMO

OBJECTIVE: To study the effect of ultrasonic irrigation in deactivating and eliminating the endotoxin in the root canals of chronic periapical periodontitis. METHODS: 10 maxillary premolars with 2 root canals extracted because of serious chronic periapical periodontitis were opened conventionally and prepared with modified double-flared technique with apical foramen sealed. 30 microL 3% H2O2 solution was introduced into each root canal and 2 minutes ultrasonic vibration was given. Samples were taken before and after ultrasonic vibration. 10 maxillary premolars with 2 root canals of chronic periapical periodontitis of 10 patients in clinic were selected. The root canals of them were instrumented as above, followed by 2 minutes ultrasonic irrigation with asepsis distilled water. Samples were taken before, after root canal preparation and after ultrasonic irrigation. The endotoxin activity of them was tested by kinetic turbidimetric limulus test. RESULTS: The mean endotoxin activity of extracted premolars before ultrasonic vibration was 4.069 EU x mL(-1) while after ultrasonic vibration it was 16.410 EU x mL(-1). There was great statistical difference between them (P < 0.01). The endotoxin activity after ultrasonic vibration was significantly higher than that of before vibration. The clinically mean endotoxin activity before, after root canal preparation and after ultrasonic irrigation were 44.860, 4.099, and 0.116 EU mL1 respectively. There was great statistical difference between the endotoxin activity before and after root canal preparation (P < 0.01). After the preparation, the endotoxin activity droped obviously. There was great statistical difference between the endotoxin activity before and after ultrasonic irrigation (P < 0.01). After ultrasonic irrigation, the endotoxin activity droped obviously. CONCLUSION: Under the condition of simulating clinical work presence, the ultrasonic irrigation can not intensify the effect of the root canal rinse solution in deactivating the endotoxin of infected root canals, but it may intensify the effect of the root canal rinse solution in eliminating the endotoxin of infected root canals.


Assuntos
Cavidade Pulpar , Irrigantes do Canal Radicular , Dente Pré-Molar , Endotoxinas , Humanos , Peróxido de Hidrogênio , Dente Molar , Periodontite Periapical , Preparo de Canal Radicular , Tratamento do Canal Radicular , Ultrassom
12.
Zhonghua Yan Ke Za Zhi ; 46(11): 964-8, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21211289

RESUMO

OBJECTIVE: To investigate the serum differentially expressed proteins in discordance of congenital esotropia phenotypes in monozygotic twins and non-strabismus ones. METHODS: SELDI-TOF-MS technology was used to detect the changes of protein expression in a couple of twins with phenotype discordance esotropia (twins A is orthotropia and twins B is esotropia). In addition, two non-twins esotropia and 2 orthotropia children with the same age were chosen. The obtained serum differential expression proteome was validated in 12 non-twins esotropia and 18 orthotropia children and initial predication by proteinum database. RESULTS: The result of SELDI-TOF-MS in 6 serums showed that four differential expression protein peaks, the molecular weight of these different proteins were 4146, 4801, 7786 and 5859, and the former 3 proteins were down-regulated and last one was up-regulated. Their features were fairly coincident with glucagons precursor, pituitary adenylate cyclase activating peptide (PACAP), cAMP dependent protein kinase inhibitor α and anti-metastasis gene (antigen). CONCLUSIONS: The expression of different proteins among the esotropic and orthotopic children was existed. The expression of different proteins was main down-regulated in the strabismus patients. Glucagons precursor, protein kinase A inhibitor α and PACAP may be related with occurrence of congenital esotropia.


Assuntos
Doenças em Gêmeos/metabolismo , Esotropia/sangue , Proteoma/análise , Pré-Escolar , Doenças em Gêmeos/sangue , Doenças em Gêmeos/genética , Esotropia/congênito , Esotropia/genética , Humanos , Masculino , Fenótipo , Proteômica , Gêmeos Monozigóticos
13.
Oral Oncol ; 46(1): 65-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20005768

RESUMO

The aim of this study was to examine the Kif2a expression and its role in tumor progression, invasion and metastasis in squamous cell carcinoma of the oral tongue (SCCOT). The study included 44 cases of primary tumor and the corresponding adjacent tissues, 20 cases of primary tumor with lymph node metastasis. Immunohistochemistry was used to observe the Kif2a expression and its correlation with clinicopathologic factors in oral tongue cancer. The immunohistochemistry showed that Kif2a expression was stronger in oral tongue cancer tissues than in paired adjacent tissues (P<0.01), and the higher expression of Kif2a was also significantly associated with lymph node metastasis (P<0.01), tumor clinical stage (P<0.01). In addition, in vitro results from transwell chamber assay showed that Tca8113 cells transfected with Kif2a-siRNA had a decreased migratory ability (P<0.01) compared to nonsense-siRNA-transfected cells. Therefore we speculate the overexpression of Kif2a might be involved in the progression, invasion and metastasis of SCCOT and Kif2a should be as a predictor for prognosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias da Língua/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Língua/patologia
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(11): 2911-3, 2010 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21284151

RESUMO

By adding the thulium oxide nanoparticles (NP) of Gd2 O3 and Eu2O3 and Nd2O3 to polymer dispersed liquid crystals (PDLC), and the transmittances of PDLC and NP-PDLC changing with voltage in visible light was tested, and the thulium oxide modulation for PDLC was studied. The results show that transmittance of Gd2O3-NP-PDLC decreases with increasing voltage when the voltage is less than 10 V. The relaxation phenomenon of the sample appears at 15 V, and its transmittance curve fluctuates slightly around that at 10 V. The transmittance of Gd2O3-NP-PDLC increases rapidly at 20 V, and its filter phenomenon emerges. And the transmittance of Eu2O3-NP-PDLC decreases with increasing voltage, but the decrease is only slight. And the transmittance of Nd2O3-NP-PDLC changes with voltage insignificantly.

15.
Artigo em Chinês | MEDLINE | ID: mdl-21604569

RESUMO

OBJECTIVE: To study the genetic characterizations of VP1 gene of human enterovirus 71 (HEV71) isolated from clinical specimens of Hand, Foot and Mouth Disease (HFMD) patients in Qinghai Province in 2008. METHODS: 335 clinical samples including stools, throat swabs and vesicle fluids were collected from HFMD patients in Qinghai Province. Viral isolation was performed, and molecular typing was performed with the positive isolates. Then 30 identified HEV71 isolates were performed for entire VP1 coding region amplification and sequencing. RESULTS: Among the 355 clinical samples, 45 human enteroviruses were isolated, and among them, 30 were identified as HEV71. Then 30 HEV71 positive isolates were performed by nucleotide sequencing. It showed that there was some difference in the nucleotide and the amino acid among the 30 HEV71 strains, the homology were 95.2%-100% and 96.6%-100%, respectively. But they all closed to HEV71 strains isolated in China after 1998, and from the phylogenetic tree constructed with 30 Qinghai HEV71 strains and other 35 HEV71 strains represented all known genotype and subgenotype HEV71 strains available from GenBank, it revealed that the 30 Qinghai HEV71 strains clustered within the C4a evolution branch of C4 subgenotype. CONCLUSION: HEV71 was isolated in HFMD patients in Qinghai province, and the HEV71 strains causing HFMD outbreaks in Qinghai province in 2008 were all belong to C4a evolution branch of C4 subgenotype with several transmission chains.


Assuntos
Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , China , Humanos , Tipagem Molecular/métodos , Análise de Sequência de DNA/métodos
16.
Zhonghua Yi Xue Za Zhi ; 89(25): 1791-3, 2009 Jul 07.
Artigo em Chinês | MEDLINE | ID: mdl-19862988

RESUMO

OBJECTIVE: To detect the expression and distribution of M4 receptor in normal guinea pigs retina. METHODS: Twenty one normal 4-week-old triad color guinea were selected. Eyes were enucleated. Seven eyes were fixed, paraffin-embedded and cut into sections. Expression and distribution of M4 receptor were detected using immunohisto chemically. The rest eyes were dissected. Tissue of retina were separated. RNA and protein of different tissue were extracted respectively. M4 receptor at mRNA level and protein level were detected by RT-PCR and Western blot methods. RESULTS: receptor at mRNA level was detected in normal guinea retina, with the amplification product at 221 bp. No product was detected in negative control. M4 receptor at protein level was detected in normal guinea retina, with signal band at 38,000. No signal was detect in negative control. As detected by immunohistochemistry, M4 receptor was detected in RPE cells, photoreceptor layer, outer nuclear layer, inner nuclear layer, most ganglion cells and the junctional zone of inner plexiform layer and inner nuclear layer. CONCLUSION: M4 receptor was expressed in normal guinea retina.


Assuntos
Proteínas do Olho/metabolismo , Receptor Muscarínico M4/metabolismo , Retina/metabolismo , Animais , Cobaias , RNA Mensageiro/genética
17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(3): 280-2, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19637477

RESUMO

OBJECTIVE: To study the deactivation of the endotoxin in artificial glass root canals with ultrasonic vibration. METHODS: 80 artificial glass root canals were randomly divided into 8 groups: Ultrasonic vibration of 5 minutes, 7 minutes, 10 minutes, ultrasonic vibration of 5 minutes together with 3% H2O2 solution, only 3% H2O2 solution, ultrasonic vibration of 5 minutes together with 5.25% NaClO solution, only 5.25% NaClO solution and the control. Standard endotoxin solution was introduced into each root canal. Different time's ultrasonic vibration was applied to different groups. After ultrasonic vibration, the endotoxin activity of each group was tested by kinetic turbidimetric limulus test. RESULT: There were no significant differences among the groups of different time ultrasonic vibration and the control (P>0.05). There was great statistical difference between each group with root canal rinse solution and the control (P<0.001). The endotoxin activity of the test was significantly lower than the control. There was no significant difference between the groups of only rinse solution and rinse solution together with ultrasonic vibration. CONCLUSION: Under the condition of this study, the only ultrasonic vibration can not deactivate the endotoxin of infected root canals and can not intensify the effect of root canal rinse solution.


Assuntos
Cavidade Pulpar , Ultrassom , Endotoxinas , Peróxido de Hidrogênio , Vibração
18.
Oral Oncol ; 45(10): 883-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19442569

RESUMO

To investigate the expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and its effects on angiogenesis and lymphangiogenesis in oral carcinoma. Immunohistochemistry was used to study the expression of CEACAM1, LYVE1 and CD31, double-labelling immunofluorescence was used to detect the co-expression of CEACAM1 and LYVE1, and double-labelling immunohistochemistry was performed to observe the co-expression of LYVE1 and CD31 in vessels. Membranous CEACAM1 was expressed in well-differentiated squamous cell carcinoma and cytoplastic CEACAM1 in poorly and moderately differentiated carcinoma (P<0.05). More CEACAM1-positive vessels were observed in CEACAM1-positive tumors with cytoplasmic expression than with membranous expression (P<0.001). Co-expression of CEACAM1 and LYVE1, LYVE1 and CD31 in vessels was more common in CEACAM1-positive tumors with cytoplasmic expression than with membranous expression (P<0.001). CEACAM1 has different distribution in oral carcinoma. Membranous CEACAM1 inhibits angiogenesis and lymphangiogenesis, but cytoplasmic CEACAM1 promotes angiogenesis, and even promotes lymphangiogenesis by mediating the transformation of vascular endothelial cells (VECs) into lymphatic endothelial cells (LECs).


Assuntos
Antígenos CD/metabolismo , Antígenos CD/fisiologia , Carcinoma de Células Escamosas/metabolismo , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/fisiologia , Linfangiogênese/fisiologia , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/fisiologia , Neovascularização Patológica/etiologia , Carcinoma de Células Escamosas/irrigação sanguínea , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/irrigação sanguínea , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas de Transporte Vesicular/metabolismo
19.
Zhonghua Yan Ke Za Zhi ; 43(7): 618-21, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17897551

RESUMO

OBJECTIVE: In order to have a better understanding about the role of the extracellular matrix molecules in the intermittent and constant exotropia, we measured the amounts of fibronectin and proteoglycan in the resected medial rectus muscles of patients with concomitant exotropia. METHODS: Thirty-one exotropic patients (including intermittent exotropia 17 cases and constant exotropia 14 cases) and 21 normal were chosen. In exotropic group, there were 7 cases with positive family history. Tissues of the medial rectus muscles were obtained from patients with concomitant exotropia during resection surgery and the specimen of medial rectus muscle from 21 normal persons was as control. All the tissues were weighted and then pulverized to obtain supernatant for enzyme linked immunosorbent assay (ELISA). The total amounts of fibronectin and proteoglycan were measured. The correlation of fibronectin and proteoglycan with age, gender, positive family history in different groups of exotropia was analyzed. RESULTS: The amount of fibronectin in the resected medial rectus muscle of patients with concomitant exotropia was significantly lower than that of normal individual (P < 0.01), and the difference of proteoglycan amount between patients and the normal control was not significant (P > 0.05). Patients with intermittent exotropia showed significantly higher concentration of fibronectin than those with constant exotropia (P < 0.01), and the amount of proteoglycan had no significant difference between two groups (P > 0.05). The amounts of proteoglycan decreased significantly with the advance of age (r = -0.8712, P < 0.01), while the amounts of fibronectin had no correction with age (r = -0.1718, P > 0.05). Neither gender nor positive family was correlated with the amounts of proteoglycan and fibronectin (P > 0.05). CONCLUSIONS: The change of fibronectin may be related to the concomitant exotropia and the development from intermittent to constant exotropia. An attention should be paid to the roles of fibronectin in the development of strabismus.


Assuntos
Exotropia/metabolismo , Matriz Extracelular/metabolismo , Músculos Oculomotores/metabolismo , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Fibronectinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteoglicanas/metabolismo , Adulto Jovem
20.
Shanghai Kou Qiang Yi Xue ; 16(3): 285-9, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17660916

RESUMO

PURPOSE: To investigate the expression and distribution of vascular endothelial growth factor(VEGF) in human dental pulp of immature and mature permanent teeth, and the relationship between VEGF and root development of human permanent teeth. METHODS: The normal teeth extracted for orthodontic or impacted reason were divided into two groups: group 1 contained 10 immature permanent teeth and group 2 contained 15 apical closed mature permanent teeth. The pulps were processed with immunohistochemically staining of VEGF. Image pro-plus 5.1 software was used to evaluate the histological sections and the data was analyzed by Chi-square test, Students't test, one-way ANOVA and SNK-q test with SPSS 13.0 software package. RESULTS: The expression of VEGF was strongly positive in the cytoplasma of pulp fibroblasts and odontoblasts in immature permanent teeth,significantly higher than in mature permanent teeth (P<0.05). The expression of VEGF was demonstrated most strongly positive in fibroblasts in the top area of apical pipe socket of immature root pulp, and gradually weakly positive toward the coronal and apical direction. CONCLUSIONS: The expression of VEGF in dental pulp of immature and mature permanent teeth shows different characteristics. VEGF may play a role in permanent tooth development and maturation.


Assuntos
Polpa Dentária/metabolismo , Dentição Permanente , Fator A de Crescimento do Endotélio Vascular/metabolismo , Humanos , Dente Molar , Raiz Dentária
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