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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(5): 927-935, 2022 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-36241235

RESUMO

OBJECTIVE: To evaluate the type of wound healing following modified crown lengthening surgery in dog model to provide a biological basis for its clinical application. METHODS: Flap surgery, traditional crown lengthening procedure and modified crown lengthening procedure were performed on the right maxillary central incisor, the left maxillary central incisor and the left maxillary first lateral incisor respectively of five male beagle dogs. The right maxillary first lateral incisors with no surgical intervention were used as controls. Thirty-six weeks after the experimental procedure, tissue blocks were harvested and prepared for histological examination and analysis. RESULTS: Histometric examination of buccolingual sections stained with hematoxylin-eosin demonstrated that the type of wound healing in the flap surgery group was re-attachment, similar to the control group. For the traditional crown lengthening surgery group, all of the five beagle dogs had lamellar cementum defects on root surface, the wound healing of four beagle dogs was new attachment accompanied by new cementum formation at cementum defect areas and the suprac-restal connective tissue was functionally oriented perpendicular to the new cementum. The wound healing of the other beagle dog was long junctional epithelial attachment, in which the junctional epithelium extended to the apical terminus of the cementum defect. In the modified crown lengthening surgery group, four beagle dogs had cementum defects on root surface (two lamellar cementum defects and two shallow platform-like cementum defects), the wound healing of three beagle dogs was new attachment, however, the supracrestal connective tissue was parallel to the root surface. The type of wound healing of another one beagle dog was long junctional epithelial attachment. Wound healing of one beagle dog in this group could not be characterized due to incomplete dissection. CONCLUSION: Wound healing in the modified crown lengthening surgery group was similar to the traditional crown lengthening surgery group, and two types of wound healing were observed: new attachment and long junctional epithelium attachment. Neither type of root treatment procedure (root planing or root reshaping) nor root surface defect pattern (the lamellar cementum defect or shallow platform-like cementum defect) influenced the observed type of wound healing.


Assuntos
Aumento da Coroa Clínica , Inserção Epitelial , Animais , Tecido Conjuntivo , Cães , Amarelo de Eosina-(YS) , Inserção Epitelial/patologia , Hematoxilina , Masculino , Raiz Dentária/cirurgia , Cicatrização
2.
Zhonghua Fu Chan Ke Za Zhi ; 55(8): 535-543, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32854478

RESUMO

Objective: To observe the changes of the expression level of long non-coding RNA (lncRNA) KCNQ1OT1 and microRNA (miR)-146a-3p in placenta tissues of preeclampsia (PE) patients, as well as their effect and mechanism on the biological functions of trophoblast cells. Methods: A total of 45 cases of hospitalized PE patients in Hainan General Hospital from July 2017 to July 2018 were selected as the PE group, 55 normal pregnant women during the same period were chosed as the control group. The expression level of KCNQ1OT1 mRNA and miR-146a-3p in the placenta tissues between two groups were detected by using quantitative real time (qRT)-PCR. Pearson's test was furtherly analyzed the correlation between them. Human trophoblast cell line (HTR8/SVneo) were randomly divided into control and lipopolysaccharide (LPS) groups, and then LPS group were divide into four sub-groups,included LPS group, short hairpin RNA (sh)-KCNQ1OT1 (after silencing the expression of KCNQ1OT1), miR-146a-3p inhibitor and sh-KCNQ1OT1+miR-146a-3p inhibitor. The targeting relationship between KCNQ1OT1 and miR-146a-3p were predicted by bioinformatics software and confirmed by luciferase assay. The cell proliferation and invasion capacities were respectively detected by cell counting kit-8 (CCK-8) and transwell assay. The expression level of KCNQ1OT1 mRNA and miR-146a-3p were detected by qRT-PCR and the protein expression level of CXC chemokine ligand 12 (CXCL12) and CXC chemokine receptor type 4 (CXCR4) were tested by western blot. Results: (1) The mRNA expression level of KCNQ1OT1 in the placenta of PE group was lower than that of control group (0.23±0.03 vs 0.51±0.04, P<0.05), and the miR-146a-3p expression level was higher than that of the control group (0.49±0.03 vs 0.31±0.03, P<0.05), there were statistical significant differences between the two groups. (2) Luciferase assay showed that there was a targeting relationship between KCNQ1OT1 and mir-146a-3p. Compared with the control group, the mRNA expression level of KCNQ1OT1 in the LPS group were significantly decreased (0.91±0.03 vs 0.35±0.03, P<0.05), and the expression level of miR-146a-3p were significantly increased (0.22±0.03 vs 0.63±0.04, P<0.05). The cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 significantly reduced in the LPS group compared with control group (all P<0.05). The mRNA expression level of KCNQ1OT1 (0.23±0.03) in the sh-KCNQ1OT1 group were further decreased, the expression of miR-146a-3p (0.85±0.03) were further increased, and the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all further reduced compared with control group,there were significant difference between two groups (all P<0.05). Comparing the miR-146a-3p inhibitor group, and sh-KCNQ1OT1+miR-146a-3p inhibitor group with the sh-KCNQ1OT1 group, respectively, the expression level of KCNQ1OT1 mRNA (0.78±0.04 vs 0.50±0.03) increased, and the expression level of miR-146a-3p (0.42±0.03 vs 0.46±0.03) decreased, the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all increased ,there were statistically significant differences (all P<0.05). Conclusion: KCNQ1OT1 could target the regulation of miR-146a-3p through CXCL12/CXCR4 pathway in the proliferation, invasion an migration of HTR8/SVneo cells, which may be involved in the pathogenesis of PE.


Assuntos
MicroRNAs/genética , Pré-Eclâmpsia/genética , RNA Longo não Codificante/genética , Trofoblastos/patologia , Feminino , Humanos , Placenta/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Pré-Eclâmpsia/patologia , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Trofoblastos/metabolismo
4.
Aliment Pharmacol Ther ; 45(12): 1542-1550, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28449186

RESUMO

BACKGROUND: Aspirin increases the risk of gastrointestinal bleeding. AIM: To investigate the risk of lower gastrointestinal bleeding (LGIB) in aspirin users. METHODS: Low-dose (75-325 mg daily) aspirin users and controls matched by age, gender and enrollment time in a 1:5 ratio were selected from 1 million randomly sampled subjects in the National Health Insurance Research Database of Taiwan. Cox proportional hazard regression models were developed to evaluate the predictors of LGIB with adjustments for age, gender, comorbidities including coronary artery disease, ischaemic stroke, diabetes, hypertension, chronic kidney disease, liver cirrhosis, chronic obstructive pulmonary disease, dyslipidemia, uncomplicated peptic ulcer disease, history of peptic ulcer bleeding, and concomitant use of clopidogrel, ticlopidine, warfarin, nonsteroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 inhibitors, steroids, proton pump inhibitors (PPIs), histamine-2 receptor antagonists (H2RAs), nitrates, alendronate, selective serotonin reuptake inhibitors (SSRIs) and calcium channel blockers. RESULTS: A total of 53 805 aspirin users and 269 025 controls were included. Aspirin group had a higher incidence of LGIB within 1 year than control group (0.20% vs 0.06%, P<.0001). Aspirin (hazard ratio [HR]: 2.75, 95% confidence interval [CI]: 2.06-3.65), NSAIDs (HR: 8.61, 95% CI: 3.28-22.58), steroids (HR: 10.50, 95% CI: 1.98-55.57), SSRIs (HR: 11.71, 95% CI: 1.40-97.94), PPIs (HR: 8.47, 95% CI: 2.26-31.71), and H2RAs (HR: 10.83, 95% CI: 2.98-39.33) were significantly associated with LGIB. CONCLUSIONS: The risk of LGIB was higher in low-dose aspirin users than in aspirin nonusers in this nationwide cohort. Low-dose aspirin, NSAIDs, steroids, SSRIs, PPIs and H2RAs were independent risk factors for LGIB.


Assuntos
Aspirina/administração & dosagem , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/efeitos adversos , Estudos de Casos e Controles , Clopidogrel , Comorbidade , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Feminino , Hemorragia Gastrointestinal/induzido quimicamente , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/complicações , Úlcera Péptica/tratamento farmacológico , Úlcera Péptica/epidemiologia , Úlcera Péptica Hemorrágica/tratamento farmacológico , Úlcera Péptica Hemorrágica/epidemiologia , Inibidores da Bomba de Prótons/uso terapêutico , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Taiwan/epidemiologia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Varfarina/uso terapêutico , Adulto Jovem
5.
J Biomed Sci ; 23: 30, 2016 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-26922801

RESUMO

BACKGROUND: TGF-ß is a key modulator in the regulation of cell proliferation and migration, and is also involved in the process of cancer development and progression. Previous studies have indicated that TGF-ß responsiveness is determined by TGF-ß receptor partitioning between lipid raft/caveolae-mediated and clathrin-mediated endocytosis. Lipid raft/caveolae-mediated endocytosis facilitates TGF-ß degradation and thus suppressing TGF-ß responsiveness. By contrast, clathrin-mediated endocytosis results in Smad2/3-dependent endosomal signaling, thereby promoting TGF-ß responsiveness. Because betulinic acid shares a similar chemical structure with cholesterol and has been reported to insert into the plasma membrane, we speculate that betulinic acid changes the fluidity of the plasma membrane and modulates the signaling pathway associated with membrane microdomains. We propose that betulinic acid modulates TGF-ß responsiveness by changing the partitioning of TGF-ß receptor between lipid-raft/caveolae and non-caveolae microdomain on plasma membrane. METHODS: We employed sucrose-density gradient ultracentrifugation and confocal microscopy to determine membrane localization of TGF-ß receptors and used a luciferase assay to examine the effects of betulinic acid in TGF-ß-stimulated promoter activation. In addition, we perform western blotting to test TGF-ß-induced Smad2 phosphorylation and fibronectin production. RESULTS AND CONCLUSIONS: Betulinic acid induces translocation of TGF-ß receptors from lipid raft/caveolae to non-caveolae microdomains without changing total level of TGF-ß receptors. The betulinic acid-induced TGF-ß receptors translocation is rapid and correlate with the TGF-ß-induced PAI-1 reporter gene activation and growth inhibition in Mv1Lu cells.


Assuntos
Células Epiteliais/metabolismo , Pulmão/metabolismo , Microdomínios da Membrana/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Triterpenos/farmacologia , Animais , Linhagem Celular , Células Epiteliais/citologia , Pulmão/citologia , Vison , Triterpenos Pentacíclicos , Ácido Betulínico
6.
Oncogene ; 35(17): 2223-34, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-26411367

RESUMO

Adenomatous polyposis coli (APC), a tumor-suppressor gene critically involved in familial adenomatous polyposis, is integral in Wnt/ß-catenin signaling and is implicated in the development of sporadic tumors of the distal gastrointestinal tract including pancreatic cancer (PC). Here we report for the first time that functional APC is required for the growth and maintenance of pancreatic islets and maturation. Subsequently, a non-Kras mutation-induced premalignancy mouse model was developed; in this model, APC haploinsufficiency coupled with p53 deletion resulted in the development of a distinct type of pancreatic premalignant precursors, mucinous cystic neoplasms (MCNs), exhibiting pathomechanisms identical to those observed in human MCNs, including accumulation of cystic fluid secreted by neoplastic and ovarian-like stromal cells, with 100% penetrance and the presence of hepatic and gastric metastases in >30% of the mice. The major clinical implications of this study suggest targeting the Wnt signaling pathway as a novel strategy for managing MCN.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Pancreáticas/genética , Proteína Supressora de Tumor p53/genética , Animais , Modelos Animais de Doenças , Feminino , Haploinsuficiência/genética , Humanos , Perda de Heterozigosidade , Camundongos , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Pancreáticas/patologia , Via de Sinalização Wnt/genética , Neoplasias Pancreáticas
7.
Genet Mol Res ; 14(4): 12684-91, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26505419

RESUMO

Black locust (Robinia pseudoacacia L.) is an ecologically and economically important species. However, it has relatively underdeveloped genomic resources, and this limits gene discovery and marker-assisted selective breeding. In the present study, we obtained large-scale transcriptome data using a next-generation sequencing platform to compensate for the lack of black locust genomic information. Increasing the amount of transcriptome data for black locust will provide a valuable resource for multi-gene phylogenetic analyses and will facilitate research on the mechanisms whereby conserved genes and functions are maintained in the face of species divergence. We sequenced the black locust transcriptome from a cDNA library of multiple tissues and individuals on an Illumina platform, and this produced 108,229,352 clean sequence reads. The high-quality overlapping expressed sequence tags (ESTs) were assembled into 36,533 unigenes, and 4781 simple sequence repeats were characterized. A large collection of high-quality ESTs was obtained, de novo assembled, and characterized. Our results markedly expand the previous transcript catalogues of black locust and can gradually be applied to black locust breeding programs. Furthermore, our data will facilitate future research on the comparative genomics of black locust and related species.


Assuntos
Etiquetas de Sequências Expressas , Robinia/genética , Regulação da Expressão Gênica de Plantas/genética , Biblioteca Gênica , Genoma de Planta/genética , Sequenciamento de Nucleotídeos em Larga Escala
8.
Br J Pharmacol ; 171(24): 5541-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25420930

RESUMO

UNLABELLED: Reorganization of the actin cytoskeleton is essential for cell motility and chemotaxis. Actin-binding proteins (ABPs) and membrane lipids, especially phosphoinositides PI(4,5)P2 and PI(3,4,5)P3 are involved in the regulation of this reorganization. At least 15 ABPs have been reported to interact with, or regulated by phosphoinositides (PIPs) whose synthesis is regulated by extracellular signals. Recent studies have uncovered several parallel intracellular signalling pathways that crosstalk in chemotaxing cells. Here, we review the roles of ABPs and phosphoinositides in chemotaxis and cell migration. LINKED ARTICLES: This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24.


Assuntos
Citoesqueleto de Actina/metabolismo , Quimiotaxia/fisiologia , Proteínas dos Microfilamentos/metabolismo , Fosfatidilinositóis/metabolismo , Movimento Celular/fisiologia , Humanos , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia
9.
Cell Death Dis ; 4: e907, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24201806

RESUMO

The androgen receptor (AR) has a critical role in promoting androgen-dependent and -independent apoptosis in testicular cells. However, the molecular mechanisms that underlie the ligand-independent apoptosis, including the activity of AR in testicular stem cells, are not completely understood. In the present study, we generated induced pluripotent stem cells (iPSCs) from bovine testicular cells by electroporation of octamer-binding transcription factor 4 (OCT4). The cells were supplemented with leukemia inhibitory factor and bone morphogenetic protein 4, which maintained and stabilized the expression of stemness genes and pluripotency. The iPSCs were used to assess the apoptosis activity following exposure to phthalate esters, including di (2-ethyhexyl) phthalates, di (n-butyl) phthalate, and butyl benzyl phthalate. Phthalate esters significantly reduced the expression of AR in iPSCs and induced a higher ratio of BAX/BCL-2, thereby favoring apoptosis. Phthalate esters also increased the expression of cyclin-dependent kinase inhibitor 1 (p21(Cip1)) in a p53-dependent manner and enhanced the transcriptional activity of p53. The forced expression of AR and knockdown of p21(Cip1) led to the rescue of the phthalate-mediated apoptosis. Overall, this study suggests that testicular iPSCs are a useful system for screening the toxicity of environmental disruptors and examining their effect on the maintenance of stemness and pluripotency, as well as for identifying the iPSC signaling pathway(s) that are deregulated by these chemicals.


Assuntos
Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Ácidos Ftálicos/farmacologia , Receptores Androgênicos/metabolismo , Testículo/citologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Bovinos , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/citologia , Masculino , Receptores Androgênicos/genética , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53
10.
Neurogastroenterol Motil ; 23(9): 840-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21714832

RESUMO

BACKGROUND: To investigate the association between the gastric emptying rate and the presence of erosive esophagitis in duodenal ulcer (DU) patients among a population with high prevalence of Helicobacter pylori infection. METHODS: Cross-sectional survey was performed in a cohort of 60 male patients with either active or healed DU, with or without the presence of erosive esophagitis. Clinical and social-demographic data, blood level of fasting gastrin, pepsinogen I & I/II ratio, and scintigraphic measurement of half emptying time (t(1/2) ) of the solid phase gastric emptying were evaluated. KEY RESULTS: Patients with active DU and erosive esophagitis tended to have higher plasma level of fasting gastrin than those without erosive esophagitis (75.11±13.74 vs 45.81±5.06pgmL(-1) , P = 0.059). In the absence of H. pylori infection, patients with healed DU and erosive esophagitis had a trend to have longer half-emptying time (t(1/2) : 96.5±6.4 vs 69.1±11.3min, P=0.0572) than those without erosive esophagitis, and statistically significant longer after excluding those diagnosed with hiatal hernia (t(1/2) : 100.8±7.9min vs 69.1±11.3min, P<0.05) from the former group. Among the healed DU patients, those with negative H. pylori infection, hiatal hernia and overweight (body mass index ≥24) had significantly increased risk of severe esophagitis. CONCLUSIONS & INFERENCES: Presence of erosive esophagitis in a subset of Taiwanese patients with healed DU and negative H. pylori status was associated with slower solid phase gastric emptying.


Assuntos
Úlcera Duodenal/complicações , Esofagite Péptica/etiologia , Esofagite Péptica/fisiopatologia , Esvaziamento Gástrico/fisiologia , Adulto , Estudos Transversais , Úlcera Duodenal/microbiologia , Gastrinas/sangue , Infecções por Helicobacter/complicações , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan
11.
Br J Cancer ; 104(7): 1178-84, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21343933

RESUMO

BACKGROUND: The purpose of this study was to detect postoperative persistent circulating tumour cells (CTCs) in stages II and III colon cancer patients undergoing curative resection and so identify a subgroup of patients who are at high risk for early relapse. METHODS: Four mRNA molecular markers including human telomerase reverse transcriptase, cytokeratin-19, cytokeratin-20, and carcinoembryonic antigen (CEA) mRNA were used to detect CTCs in 141 stages II and III colon cancer patients undergoing curative resection to determine the significance of CTCs in postoperative early relapse. RESULTS: Out of 141 patients, postoperative early relapse and non-early relapse/no relapse was found in 48 (34.0%) patients and 93 (66.0%) patients, respectively. Univariately, postoperative early relapse was significantly correlated with lymph node metastasis (P=0.025), vascular invasion (P=0.002), perineural invasion (P=0.001), laparoscopic surgery (P=0.019), high postoperative serum CEA levels (P=0.001), and presence of persistent postoperative CTCs (P<0.001). Using a multivariate proportional hazards regression analysis, the presence of perineural invasion (P=0.034; HR, 1.974; 95% CI: 1.290-3.861), high postoperative serum CEA levels (P=0.020; HR, 2.377; 95% CI: 1.273-4.255), and the presence of persistent postoperative CTCs (P<0.001; HR, 11.035; 95% CI: 4.396-32.190), were demonstrated to be independent predictors for postoperative early relapse. Furthermore, the presence of persistent postoperative CTCs was strongly correlated with a poorer disease-free and overall survival (both P<0.001). CONCLUSIONS: This study suggests that molecular detection of persistent postoperative CTCs is a prognostic predictor of early relapse in UICC stage II/III colon cancer patients, and thus could help to define patients with this tumour entity for an enhanced follow-up and therapeutic program.


Assuntos
Neoplasias do Colo/patologia , Recidiva Local de Neoplasia/diagnóstico , Células Neoplásicas Circulantes , Adulto , Idoso , Idoso de 80 Anos ou mais , Coleta de Amostras Sanguíneas , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/cirurgia , Detecção Precoce de Câncer , Feminino , Humanos , Queratina-19/genética , Queratina-20/genética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pós-Operatório , Prognóstico , RNA Mensageiro/análise , Telomerase/genética
12.
Opt Express ; 18(24): 25232-40, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-21164870

RESUMO

Selective filling of photonic crystal fibers with different media enables a plethora of possibilities in linear and nonlinear optics. Using two-photon direct-laser writing we demonstrate full flexibility of individual closing of holes and subsequent filling of photonic crystal fibers with highly nonlinear liquids. We experimentally demonstrate solitonic supercontinuum generation over 600 nm bandwidth using a compact femtosecond oscillator as pump source. Encapsulating our fibers at the ends we realize a compact ultrafast nonlinear optofluidic device. Our work is fundamentally important to the field of nonlinear optics as it provides a new platform for investigations of spatio-temporal nonlinear effects and underpins new applications in sensing and communications. Selective filling of different linear and nonlinear liquids, metals, gases, gain media, and liquid crystals into photonic crystal fibers will be the basis of new reconfigurable and versatile optical fiber devices with unprecedented performance. Control over both temporal and spatial dispersion as well as linear and nonlinear coupling will lead to the generation of spatial-temporal solitons, so-called optical bullets.

13.
Neuroscience ; 171(4): 1102-8, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20884329

RESUMO

The lateral nucleus of the amygdala (LA) is a critical structure involved in fear conditioning. We recently showed that regulated exocytosis and endocytosis of postsynaptic A-amino-3-hydroxy-5-methylisoxazole-4-propionate subtype of glutamate receptors (AMPARs) are involved in the expression of N-methyl-D-aspartate subtype glutamate receptors (NMDARs) dependent long-term potentiation (LTP) and long-term depression (LTD) in coronal slices of the LA. However, the molecular mechanisms of this effect remain unclear. In the present study, we investigated the role of distinct NMDAR subtypes in the endocytosis of AMPARs during LTD expression at the synapses of the thalamic inputs to the LA neurons. Here we show that the NMDARs antagonist DL-2-amino-5-phosphonovalerate (D-APV) blocked the induction of LTD and thus prevented endocytosis of surface AMPARs, indicating that NMDAR activation enhanced the internalization of AMPARs in LTD expression. Furthermore, the selective blocking of GluN2B-containing NMDARs completely abolished the NMDAR-induced AMPAR endocytosis, whereas preferential inhibition of GluN2A-containing NMDARs did not block the NMDAR-induced AMPAR endocytosis during LTD expression. These results suggest that there exist a preferred NMDAR subtype for AMPAR internalization and activation of GluN2B-containing NMDARs represent the predominate pathway triggered during the early stages of this NMDAR-induced endocytosis of AMPARs during LTD in the thalamic inputs to the LA of juvenile rats.


Assuntos
Tonsila do Cerebelo/fisiologia , Depressão Sináptica de Longo Prazo/fisiologia , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/fisiologia , Tonsila do Cerebelo/citologia , Animais , Animais Recém-Nascidos , Biotinilação/métodos , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , Exocitose/efeitos dos fármacos , Técnicas In Vitro , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Técnicas de Patch-Clamp , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
14.
Eur J Clin Invest ; 39(9): 807-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19614952

RESUMO

BACKGROUND: Amoxicillin-resistant Helicobacter pylori with minimal inhibitory concentration (MIC) >or= 256 mg L(-1) was isolated from a gastritis patient. The aims were to investigate the mechanism of high-level amoxicillin resistance in H. pylori. MATERIALS AND METHODS: The beta-lactamase production was determined by means of nitrocefin sticks and the presence of gene encoding the beta-lactam antibiotic resistance enzyme TEM beta-lactamase was analysed by polymerase chain reaction (PCR), sequencing and dot-blot hybridization. Sequencing analysis of pbp1A gene was performed and amoxicillin-susceptible isolate was transformed with pbp1A PCR products from the resistant isolate. The expression of hefC efflux system was analysed using real-time quantitative PCR. RESULTS: Activity of beta-lactamase was detected. Sequence analysis showed that the PCR product derived from H. pylori 3778 was identical to the bla(TEM-1) (GenBank accession EU726527). Dot-blot hybridization confirmed the presence of beta-lactamase gene bla(TEM-1.) By transformation of PCR product of mutated pbp1A gene from H. pylori 3778 into amoxicillin-susceptible strain showed that substitutions in Thr(556)-->Ser, Lys(648)-->Gln, Arg(649)-->Lys and Arg(656)-->Pro contribute to low-level amoxicillin resistance. The MIC of amoxicillin for the transformants was 0.75 mg L(-1). Over-expression of hefC was not found. CONCLUSIONS: High-level amoxicillin resistance is associated with beta-lactamase production in H. pylori. Low-level amoxicillin resistance is linked to a point mutation on pbp1A. Because H. pylori can exchange DNA through natural transformation, spreading of bla(TEM-1) amoxicillin resistance gene among H. pylori is a potential threat when treating H. pylori infection.


Assuntos
Amoxicilina/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/isolamento & purificação , beta-Lactamases/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Regulação Bacteriana da Expressão Gênica/genética , Infecções por Helicobacter/genética , Helicobacter pylori/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , beta-Lactamases/metabolismo
15.
Eur J Clin Invest ; 38(10): 760-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18837801

RESUMO

BACKGROUND: The relationship between Helicobacter pylori (Hp) infection and oesophageal squamous-cell carcinoma (ESCC) risk is still inconclusive. Our previous study found an inverse association between the two, but its mechanism is still unknown. Thus, we conducted in vitro studies to clarify the issue. MATERIALS AND METHODS: One ESCC (CE 81T/VGH) cell line was co-cultured with Hp, using one gastric adenocarcinoma (AGS) cell line as the control. Hp-induced cell apoptosis was determined by flow cytometry, terminal transferase-mediated dUTP nick end labelling (TUNEL) assay and staining; caspase-3 protein expressions in cell lysates were detected by Western immunoblot. RESULTS: Increased apoptosis was found in CE 81T/VGH, but not in AGS cells, by flow cytometry and TUNEL assay after being co-cultured with Hp at the multiplicity of infection of 1/100 (but not at 1/400) for 36 h. The amount of activated caspase-3 (17/19 kDa) also increased in CE 81T/VGH, but not in AGS cells, after co-culturing with Hp at MOI of 1/100 for 36 h. The results were confirmed by triplicate experiments in which the different apoptotic assays remained consistent. CONCLUSIONS: Our study provides indirect evidence of the inverse association between Hp infection and ESCC risk, which is possibly due to Hp-induced apoptosis in ESCC cells. A further in vivo study is necessary to confirm our findings.


Assuntos
Carcinoma de Células Escamosas/microbiologia , Neoplasias Esofágicas/microbiologia , Helicobacter pylori/fisiologia , Anexina A5/análise , Apoptose , Biomarcadores/análise , Carcinoma de Células Escamosas/patologia , Caspase 3/análise , Linhagem Celular Tumoral , Neoplasias Esofágicas/patologia , Citometria de Fluxo , Infecções por Helicobacter/patologia , Humanos , Marcação In Situ das Extremidades Cortadas
16.
Eur J Clin Invest ; 38(6): 404-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18435764

RESUMO

BACKGROUND: A standard third-line therapy for Helicobacter pylori infection is lacking, and antimicrobial sensitivity data for patients who failed eradication therapy are often unavailable in clinical practice. We therefore designed the prospective study to assess the efficacy of levofloxacin, amoxicillin, bismuth and rabeprazole quadruple therapy as a third-line treatment for H. pylori infection. PATIENTS AND METHODS: From September 2005 to August 2007, 37 consecutive H. pylori-infected patients who had failed standard first-line and second-line treatments underwent a 10-day quadruple therapy comprising rabeprazole (20 mg b.i.d.), bismuth subcitrate (300 mg q.d.s.), amoxicillin (500 mg q.d.s.) and levofloxacin (500 mg o.d.). Follow-up endoscopy with rapid urease test, histological examination and culture was performed at 6 weeks after the end of treatment to evaluate the response to therapy. RESULTS: Helicobacter pylori was successfully eradicated in 31 out of 37 patients (84% by both intention-to-treat analysis and per-protocol analysis). All patients complied with the eradication therapies, and only seven patients (19%) complained of mild-to-moderate adverse events. Amoxicillin- and levofloxacin-resistant strains were observed in 17% and 22% of the patients, respectively. There were no significant differences between H. pylori eradication rates and antibiotic resistances. CONCLUSIONS: The 10-day levofloxacin- and amoxicillin-based quadruple therapy is well tolerated and achieves a high eradication rate as a third-line empirical treatment for H. pylori infection.


Assuntos
Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Terapia de Salvação/métodos , 2-Piridinilmetilsulfinilbenzimidazóis/uso terapêutico , Adulto , Hidrocarboneto de Aril Hidroxilases/genética , Distribuição de Qui-Quadrado , Citocromo P-450 CYP2C19 , Farmacorresistência Bacteriana , Quimioterapia Combinada , Feminino , Genótipo , Humanos , Levofloxacino , Masculino , Pessoa de Meia-Idade , Ofloxacino/uso terapêutico , Compostos Organometálicos/uso terapêutico , Seleção de Pacientes , Polimorfismo Genético , Estudos Prospectivos , Rabeprazol , Resultado do Tratamento
17.
Int J Biol Markers ; 23(4): 244-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19199273

RESUMO

First-line treatment of metastatic colorectal cancer with combinations of cetuximab and irinotecan-based or oxaliplatin-based chemotherapy has shown promising efficacy. The clinical response to such treatment is generally assessed by tumor measurement through imaging. This study was performed to evaluate the correlation between serial changes in imaging results and carcinoembryonic antigen (CEA) levels. In 64 patients with metastatic colorectal cancer receiving cetuximab plus FOLFIRI or FOLFOX-4 chemotherapy we retrospectively analyzed the relationship between changes in serum CEA and changes in imaging results throughout the treatment course. Response in terms of serum CEA change was defined as a >/=50% drop in CEA level for more than 4 weeks. The sensitivity and specificity of serum CEA changes after targeted chemotherapy in relation to imaging results were 80.5% (33/41) and 73.9% (17/23), respectively, with a diagnostic accuracy of 78.1% (50/64). The progression-free survival time of responders assessed by serum CEA change was significantly longer than that of nonresponders (p=0.0091). Our results highlight the importance of serum CEA monitoring in assessing the response to targeted chemotherapy and in predicting the prognosis of patients with metastatic colorectal cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Cetuximab , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento
19.
Neuroscience ; 146(3): 901-6, 2007 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-17412517

RESUMO

The central piriform cortex (cPC) is considered to be critically involved in the generation and propagation of kindled seizures. Our previous study found that low-frequency stimulation (LFS) of the cPC inhibits the development process of amygdala kindling. In this study, we determined whether unilateral LFS of the cPC had an inhibitory effect on amygdaloid-kindled seizures in Sprague-Dawley rats. When fully-kindled seizures were achieved by daily amygdala electrical stimulation (2 s train of 1 ms pulses at 60 Hz and 150-300 microA), LFS (15 min train of 0.1 ms pulses at 1 Hz and 50-150 microA) was applied to the ipsilateral or contralateral cPC 1 s after cessation of kindling stimulation for 10 days. LFS of the ipsilateral cPC significantly decreased the incidence of generalized seizures and seizure stage, and shortened cumulative afterdischarge duration and cumulative generalized seizure duration. LFS of the contralateral cPC also significantly decreased the expression of seizure stage, but had no appreciable effect on the generalized seizure incidence, cumulative afterdischarge duration and cumulative generalized seizure duration. On the other hand, LFS of the ipsilateral cPC significantly increased the afterdischarge threshold and further increased the differences of current intensity between afterdischarge threshold and generalized seizure threshold. Our data suggest that LFS of the cPC may be an effective method of inhibiting kindled seizures by preventing both afterdischarge generation and propagation. It provide further evidence that brain regions like the cPC, other than the seizure focus, can serve as targets for deep brain stimulation treatment of epilepsy.


Assuntos
Tonsila do Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Excitação Neurológica/fisiologia , Convulsões/fisiopatologia , Animais , Estimulação Elétrica , Eletroencefalografia , Epilepsia Generalizada/fisiopatologia , Lateralidade Funcional/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
20.
Eur Surg Res ; 39(4): 245-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17457032

RESUMO

BACKGROUND: To evaluate the prognostic significance of pre- and postoperative serum carcinoembryonic antigen(CEA) levels in colorectal cancer (CRC) patients. METHODS: 425 CRC patients underwent curative resection at our institution. Their pre- and postoperative serum CEA level was classified into two groups according to concentration: normal CEA (<5.0 ng/ml) and abnormal CEA (> or =5.0 ng/ml). RESULTS: Of all patients, abnormal pre- and postoperative serum CEA levels were observed in 181 (42.6%) and 48 (11.3%) patients, respectively. Abnormal preoperative serum CEA level was significantly correlated with the tumor located in the colon, the depth of tumor invasion, the status of lymph node metastasis, UICC stage, and the presence of postoperative relapse (p < 0.05). Concurrently, an abnormal postoperative serum CEA level was also prominently related to the above corresponding parameters (p < 0.05), except for the tumor location. Patients with a failed conversion of abnormal preoperative value to normal postoperative concentration were found to have the worst overall survival rate. Abnormal pre- and postoperative serum CEA levels were single independent predictors for survival and postoperative relapse, respectively. CONCLUSIONS: The identification of abnormal pre- and postoperative serum CEA levels may be useful in the auxiliary cancer prognosis or postoperative surveillance of CRC patients.


Assuntos
Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/mortalidade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Idoso , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/mortalidade , Valor Preditivo dos Testes , Prognóstico , Taxa de Sobrevida
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