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Resumo Fundamento: A doença cardiovascular é a principal causa de morte em todo o mundo. A apoptose mediada por hipóxia em cardiomiócitos é uma das principais causas de distúrbios cardiovasculares. O tratamento com a proteína do fator de crescimento endotelial vascular (VEGF, do inglês vascular endothelial growth factor) foi testado, mas as dificuldades operacionais limitaram seu uso. Entretanto, com os avanços da terapia gênica, aumentou o interesse na terapia gênica baseada no VEGF em doenças cardiovasculares. No entanto, o mecanismo preciso pelo qual a reposição de VEGF resgata os danos pós-hipóxia em cardiomiócitos não é conhecido. Objetivos: Investigar o efeito da expressão de VEGF121 pós-hipóxia utilizando cardiomiócitos de ratos neonatos. Métodos: Cardiomiócitos isolados de ratos neonatos foram utilizados para estabelecer um modelo in vitro de lesão cardíaca induzida por hipóxia. O efeito da superexpressão de VEGF, isolado ou em conjunto com inibidores de moléculas pequenas que têm como alvo os canais de cálcio, receptores sensíveis ao cálcio (CaSR, do inglês calcium-sensitive receptors) e calpaína, no crescimento e proliferação celular em lesão de cardiomiócitos induzidos por hipóxia, foram determinados com ensaio de MTT, coloração TUNEL, coloração com Anexina V/PI, lactato desidrogenase e atividade da caspase. Para análise estatística, um valor de p<0,05 foi considerado significativo. Resultados: Verificou-se que o efeito do VEGF121 foi mediado por CaSR e calpaína, mas não foi dependente dos canais de cálcio. Conclusões: Nossos resultados, mesmo em um ambiente in vitro, estabelecem as bases para uma validação futura e testes pré-clínicos da terapia gênica baseada em VEGF em doenças cardiovasculares.
Abstract Background: Cardiovascular disease is the major cause of death worldwide. Hypoxia-mediated apoptosis in cardiomyocytes is a major cause of cardiovascular disorders. Treatment with vascular endothelial growth factor (VEGF) protein has been tested but operational difficulties have limited its use. However, with the advancements of gene therapy, interest has risen in VEGF-based gene therapy in cardiovascular disorders. However, the precise mechanism by which VEGF replenishment rescues post-hypoxia damage in cardiomyocytes is not known. Objectives: To investigate the effect of post-hypoxia VEGF121 expression using neonatal rat cardiomyocytes. Methods: Cardiomyocytes isolated from neonatal rats were used to establish an in vitro model of hypoxia-induced cardiac injury. The effect of VEGF overexpression, alone or in combination with small-molecule inhibitors targeting calcium channel, calcium sensitive receptors (CaSR), and calpain on cell growth and proliferation on hypoxia-induced cardiomyocyte injury were determined using an MTT assay, TUNEL staining, Annexin V/PI staining, lactate dehydrogenase and caspase activity. For statistical analysis, a value of P<0.05 was considered to be significant. Results: The effect of VEGF121 was found to be mediated by CaSR and calpain but was not dependent on calcium channels. Conclusions: Our findings, even though using an in vitro setting, lay the foundation for future validation and pre-clinical testing of VEGF-based gene therapy in cardiovascular diseases.
Assuntos
Animais , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptores de Detecção de Cálcio/metabolismo , Peptídeo Hidrolases/metabolismo , Miócitos Cardíacos/metabolismo , Hipóxia , MitocôndriasRESUMO
Objective To study the differences of the phenoloxidase (PO) relative activity among ribbed shelled Oncomelania hupensis, smooth shelled O. hupensis and Cipangopaludina chinensis. Methods The crude PO fluid was extracted from the soft tissue of O. hupensis and C. chinensis by homogenation and centrifugation. The PO activity was detected with catechol as the substrate in the reaction systems. Results The PO relative activities in the ribbed shelled O. hupensis, smooth shelled O. hupensis and C. chinensis were (25.72 ± 2.27), (14.56 ± 1.24) U / mL and (13.72 ± 1.06) U / mL. The PO relative activity in the smooth shelled O. hupensis was higher than that in the ribbed shelled O. hupensis (q = 21.46, P < 0.05) and C. chinensis (q = 12.00, P < 0.05), while the difference between the PO relative activities of the latter two was not statistically significant (q = 1.62, P > 0.05) . Conclusion There is a difference in the relative PO activity between O. hupensis and C. chinensis, which may be related to the living environment of snails.
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Objective: To investigate the inhibitory effect of capsaicin on the growth of breast cancer MDA-MB-231 cells transplanted tumour in nude mice and its possible molecular mechanism. Method: Transplanted tumor model of breast cancer MDA-MB-231 cells in nude mice were established. Then the tumor-bearing mice were randomly divided into 4 groups:model group, and low, medium and high-dose capsaicin groups (5, 10, 20 mg·kg-1). Mice of low, medium and high-dose capsaicin groups (5, 10, 20 mg·kg-1) were intraperitoneally injected with the corresponding dose of capsaicin, and the model group was injected with the same volume of phosphate buffer saline (PBS), once every 3 days, for a total of 8 times in succession. Body weight of mice and transplantation tumor volume were measured before each injection of capsaicin. Mice of each group were put to death 24 h after the last administration, and then the tumor volume, mass and the tumor inhibitory rate were calculated. The protein expression levels of high mobility group box 1 (HMGB1) and Toll-like receptors 4(TLR4) were measured by immunohistochemistry and Western blot. Result: No significant difference was observed between each group in body weight. However, compared with the model group, capsaicin (5, 10, 20 mg·kg-1) remarkably inhibited the tumor volume and mass (PPP-1) also markedly inhibited the protein expression levels of HMGB1 and TLR4 (PConclusion: Capsaicin remarkably inhibits the growth of breast cancer MDA-MB-231 cells transplanted tumour in nude mice, and the possible mechanism may be related to the down-regulation of HMGB1 and TLR4 at the protein level.
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Objective: To investigate the effect of capsaicin on the migration and invasion of human breast cancer MCF-7 cells and the underlying molecular mechanism. Method: Three capsaicin intervention groups of different concentrations (25, 50, 75 μmol·L-1) and a blank group were set up. After MCF-7 cells were treated with different concentrations of capsaicin (25, 50, 75 μmol·L-1) for 24 h, the cell migration and invasion abilities were assessed by Transwell migration and invasion assay, respectively. Meanwhile, the mRNA level of silent information regulator 2 homolog 1 (SIRT1) and DNA polymerase δ catalytic subunit p125 encoding gene POLD1 (POLD1) were detected by Real-time polymerase chain reaction (Real-time PCR). The protein levels of SIRT1 and DNA polymerase δ catalytic subunit p125 (p125) were detected by Western blot. Result: Compared with the blank group, the number of transmembrane cells was significantly reduced, and the mobility was significantly decreased (P-1) in MCF-7 cells for 24 h. Capsaicin (25, 50, 75 μmol·L-1) significantly down-regulated the mRNA and protein expressions of SIRT1 (P-1) in MCF-7 cells for 24 h. Furthermore, capsaicin (25, 50, 75 μmol·L-1) also significantly down-regulated the mRNA expression of POLD1 and the protein expression of p125 (P-1) in MCF-7 cells for 24 h. Conclusion: Capsaicin remarkably inhibits the cell migration and invasion of breast cancer MCF-7 cells, and the possible mechanism may be related to the down-regulation of SIRT1 and POLD1 mRNA expression levels and SIRT1 and p125 protein expression levels.
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Objective Toexploretheroleofmodel-basediterativereconstruction (MBIR)algorithminimprovingthequalityof thyroidCTimagesbyreducinghardeningartifactsattheentrancetothethorax.Methods ChestCTscansof20patientswiththyroidnoduleswere retrospectivelyreviewed.AlgorithmsofFBP,ASIR40,MBIRSTNDandMBIRNR40 wereusedtoreconstructatthe0.625mmslicethickness.Region ofinterestwasplacedonthecoronalimageswiththemostobvioushardeningartifacts.ThestandarddeviationsoftheCTvaluesof theleftandrightthyroidarteriesandthesurroundingnormalthyroidtissueweremeasured,furthermore,thevalueofthyroidartifact index(AI)andAI=sqrt(SDa2-SDb2)werecalculated.Tworadiologistsused4-pointmethodtoassessimageartifactssubjectivly.(1 point,severeartifacts,unclearthyroidrimsandnodules,undiagnosed;2points,moderateartifacts,poorlydisplayingthyroid margins andinternaldetails,affectivediagnosis;3points,mildartifacts,showingthyroid marginandinternaldetails,noaffectingthediagnosis;4 points ,no ribbon artifacts ,displaying thyroid edge and internal details very w ell ).ANOVA and paired t-test w ere used to co m pare the CTvaluesofnormalthyroidtissueofleftandrightlobeamongdifferentreconstructedimagesofthyroid.Subjectivescoredifferenceswere testedusingthe W ilcoxon symbolscale.Results ThevalueofCTreductionandAIatFBPandASIR40reconstructionimagesweresignificantly greaterthanthoseatMBIRSTNDandMBIRNR40reconstructionimages. Whiletherewerenodifferenceofleftandrightlobeofthyroid CTreductionand AIvalueatFBPand ASIR40reconstruction imagesnorthoseatMBIRSTNDandMBIRNR40reconstructionimages. SubjectiveevaluationofclavicleartifactswasincreasedatMBIRSTND and MBIRNR40image,andMBIRNR40imagehadoptimalsubjectiveevaluationresults(P<0.05).Conclusion MBIRcansignificantlyreducethe impactoftheclavicularharnesshardeningartifactsandnoiseonthethyroidanditsnodulesduringCTscans,especiallyoptimizingthe low-densitycontrastsettingofMBIRNR40.
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Objective To study the differences of the phenoloxidase (PO) relative activity among ribbed shelled Oncomelania hupensis, smooth shelled O. hupensis and Cipangopaludina chinensis. Methods The crude PO fluid was extracted from the soft tissue of O. hupensis and C. chinensis by homogenation and centrifugation. The PO activity was detected with catechol as the substrate in the reaction systems. Results The PO relative activities in the ribbed shelled O. hupensis, smooth shelled O. hupensis and C. chinensis were (25.72 ± 2.27), (14.56 ± 1.24) U / mL and (13.72 ± 1.06) U / mL. The PO relative activity in the smooth shelled O. hupensis was higher than that in the ribbed shelled O. hupensis (q = 21.46, P < 0.05) and C. chinensis (q = 12.00, P < 0.05), while the difference between the PO relative activities of the latter two was not statistically significant (q = 1.62, P > 0.05) . Conclusion There is a difference in the relative PO activity between O. hupensis and C. chinensis, which may be related to the living environment of snails.
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Objective To retrospectively summarize the normal reference range of trachea wall thickness,lumen diameter,wall area and wall area ratio[WA%=mean wall area/(mean wall area+lumen area)]of Chinese healthy adults,and its related factors. Also,to observe the difference of inner diameter between superior and inferior bronchus.Methods Based on computer measurement techniques of bronchus,a CT quantitative analysis was carried out in 701 cases of normal healthy people who had negative results in lung cancer screening of health examination at our hospital.Results The value of trachea wall thickness,lumen diameter,wall area and wall area ratio was(1.322 mm,18.024 mm,78.93 mm2 ,0.27)respectively.In different gender,the trachea wall thickness,lumen diameter,wall area and wall area ratio had statistical significance (P<0.05).Also,they had good consistency with gender (r=-0.512,-0.472,-0.559,0.315).In different gender and age,the difference of inner diameter between the superior bronchus and inferior bronchus was always a positive value.Conclusion The CT quantitative analysis method has advantages of convenience,direct-vie-wing and accuracy.It is good for quantitative detection and research of bronchus structure.Bronchial wall thickness,lumen diameter, wall area and wall area ratio have significant difference because of gender.The inner diameter of superior bronchus is always greater than that of the inferior bronchus.