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Gastric cancer (GC) is a common malignant tumor, posing a great threat to human's health and life. Previous studies have suggested aberrant expression of long non-coding RNAs (lncRNAs) in GC. This study elucidated the effects of lncRNA ACTA2-AS1 on the biological characteristics of GC. Gene expression in stomach adenocarcinoma (STAD) samples compared with normal tissues and the correlation between gene expression and prognosis of STAD patients were analyzed using bioinformatic tools. Gene expression at protein and mRNA levels in GC and normal cells was tested by western blotting and RT-qPCR. The subcellular localization of ACTA2-AS1 in AGS and HGC27 cells was identified by nuclear-cytoplasmic fractionation and FISH assay. EdU, CCK-8, flow cytometry analysis, TUNEL staining assays were conducted to evaluate the role of ACTA2-AS1 and ESRRB on GC cellular behaviors. The binding relationship among ACTA2-AS1, miR-6720-5p and ESRRB was verified by RNA pulldown, luciferase reporter assay and RIP assay. LncRNA ACTA2-AS1 was underexpressed in GC tissues and cell lines. ACTA2-AS1 elevation suppressed GC cell proliferation and induced apoptosis. Mechanistically, ACTA2-AS1 directly bound to miR-6720-5p and subsequently promoted the expression of target gene ESRRB in GC cells. Furthermore, ESRRB knockdown reversed the influence of ACTA2-AS1 overexpression on GC proliferation and apoptosis. ACTA2-AS1 plays an antioncogenic role in GC via binding with miR-6720-5p to regulate ESRRB expression.
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MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Receptores de Estrogênio/genética , Actinas/genéticaRESUMO
OBJECTIVE: Fangcang shelter hospital is a form of large temporary hospital developed in China to tackle public health events. Through the case study and analysis of managing a nursing unit in a huge Fangcang shelter hospital transformed from the National Exhibition and Convention Center during the Omicron wave in Shanghai, China between April 9, 2022 and May 24, 2022, this paper aimed to highlight critical implications of public health nurses in health emergencies. DESIGN: A case study was conducted using data collected from a nursing unit with 570 beds. The five characteristics of management were organized as follows: human resource management, establishment and optimization of the core workflow, safety management of high-risk patients, the grid cooperation mechanism with patient volunteers, as well as humanistic nursing. RESULTS: Analysis of the data of the nursing unit indicated close team cooperation, efficient and orderly process scheduling, good outcomes of patients, and the indispensable role of volunteers. CONCLUSION: Practice indicated that nursing unit management in a large Fangcang shelter hospital is important to ensure medical order and efficiency. This practical experience can provide valuable reference and data to support for the nursing management of large-scale public health events, such as infectious disease epidemics.
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COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Hospitais Especializados , Unidades Móveis de Saúde , China/epidemiologiaRESUMO
The system of hepatocyte growth factor (HGF) and its receptor c-Met plays a critical role in tumor invasive growth and metastasis. The mortality rate of colorectal cancer (CRC), one of the most commonly diagnosed malignancies, is increased by it gradual development into metastasis, most frequently in the liver. Overexpression of c-Met, the protein tyrosine kinase receptor for the HCF/scatter factor, has been implicated in the progression and metastasis of human colorectal carcinoma. In this study, we aimed to investigate the role of c-Met in CRC liver metastasis and illustrate the clinical impact of regulating HGF/c-Met signaling in patients with CRC liver metastasis. We found that (I) higher levels of c-Met expression (mRNA and Protein) in CRC liver metastasis than primary CRC by assessing the patient tissue samples; (II) a positive correlation of c-Met expression with tumor stages of CRC liver metastasis, as well as c-Met expression in CRC, live metastasis concurred with regional lymph node metastasis; (III) the clinical impact of downregulation of HGF/c-Met signaling on the reduction of proliferation and invasion in CRC liver metastasis. Therefore, we demonstrate that the regulation of HGF/c-Met pathways may be a promising strategy in the treatment of patients with CRC liver metastasis.
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Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/biossíntese , Neoplasias Hepáticas , Fígado/metabolismo , Proteínas Proto-Oncogênicas c-met/biossíntese , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade NeoplásicaRESUMO
PURPOSE: One of the current challenges facing cancer gene therapy is the tumour-specific targeting of therapeutic genes. Effective targeting in gene therapy requires accurate spatial and temporal control of gene expression. To develop a sufficient and accurate tumour-targeting method for cancer gene therapy, we have investigated the use of hyperthermia to control the expression of a transgene under the control of the human telomerase reverse transcriptase (hTERT) promoter and eight heat shock elements (8HSEs). MATERIALS AND METHODS: Luciferase reporters were constructed by inserting eight HSEs and the hTERT promoter (8HSEs-hTERTp) upstream of the pGL4.20 vector luciferase gene. The luciferase activity of the hTERT promoter and 8HSEs-hTERT promoter were then compared in the presence and absence of heat. The differences in luciferase activity were analysed using dual luciferase assays in SW480 (high hTERT expression), MKN28 and MRC-5 cells (low hTERT expression). The luciferase activity of the Hsp70B promoter was also compared to the 8HSEs-hTERT promoter in the above listed cell lines. Lentiviral vector and heat-induced expression of EGFP expression under the control of the 8HSEs-hTERT promoter in cultured cells and mouse tumour xenografts was measured by reverse transcription polymerase (RT-PCR), Western blot and immunofluorescence assays. RESULTS: hTERT promoter activity was higher in SW480 cells than in MKN28 or MRC-5 cells. At 43 °C, the luciferase activity of the 8HSEs-hTERT promoter was significantly increased in SW480 cells, but not in MKN28 or MRC-5 cells. Importantly, the differences in luciferase activity were much more obvious in both high (SW480) and low (MKN28 and MRC-5) hTERT expressing cells when the activity of the 8HSEs-hTERT promoter was compared to the Hsp70B promoter. Moreover, under the control of 8HSEs-hTERT promoter in vitro and in vivo, EGFP expression was obviously increased by heat treatment in SW480 cells but not in MKN28 or MRC-5 cells, nor was expression increased under normal temperature conditions. CONCLUSIONS: The hTERT promoter is a potentially powerful tumour-specific promoter and gene therapy tool for cancer treatment. Incorporating heat-inducible therapeutic elements (8HSEs) into the hTERT promoter may enhance the efficiency and specificity of cancer targeting gene therapy under hyperthermic clinical conditions.
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Terapia Genética , Proteínas de Choque Térmico HSP70/genética , Neoplasias/terapia , Telomerase/genética , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Proteínas de Fluorescência Verde/genética , Resposta ao Choque Térmico , Temperatura Alta , Humanos , Luciferases/metabolismo , Camundongos Endogâmicos BALB C , Neoplasias/genética , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: To study the expression of human lysozyme-like protein 6 (LYZL6) in the male reproductive system and its physiological role. METHODS: The recombinant P. pastoris strain was cultured and induced with methanol to express LYZL6, followed by purification using chitin affinity chromatography. The bactericidal activity of the recombinant LYZL6 was observed by bilayer agar plate diffusion assay, and then the recombinant protein was used as an immunogen to generate polyclonal antibodies, whose specificity was examined by ELISA. The distribution of LYZL6 in the human tissue and semen was identified by Western blotting and the subcellular localization in the testis was investigated by immunohistochemistry. RESULTS: At pH 5.6, recombinant LYZL6 exhibited a high bacteriolytic activity against M. lysodeikticus. ELISA analysis showed that the anti-LYZL6 polyclonal antibodies could bind the recombinant protein with a high specificity. Western blot manifested the expression of LYZL6 in the testis and epididymis, higher in the former than in the latter. LYZL6 was also detected in the sperm protein extract, while protein bands were not observed in the seminal plasma. Immunodetection with a specific antiserum localized the LYZL6 protein in the late spermatocytes and round spermatids. CONCLUSIONS: LYZL6 has a higher bacteriolytic activity under low pH condition and is bound to spermatozoa after secreted in the testicular epithelia, suggesting that LYZL6 could act as a potential hydrolase for carbohydrates in zona pellucida penetration.
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Epididimo/metabolismo , Muramidase/metabolismo , Testículo/metabolismo , Western Blotting , Humanos , Masculino , Muramidase/genética , Pichia/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismoRESUMO
Life-threatening gastrointestinal bleeding during the rescue of acute coronary syndrome with repeated cardiac arrest is a difficult challenge to overcome during treatment. The success rate of rescue can be improved through the multidisciplinary cooperation of the rescue team, the selection of a reasonable rescue plan, and timely implementation. Surgical hemostasis has rarely been reported in the literature. Here, we have reported our successful treatment experience with a case of acute coronary syndrome that was complicated by massive gastrointestinal hemorrhage and required an operation to stop the bleeding.
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OBJECTIVE: To investigate whether chlorophyllin could protect human umbilical vein endothelial cell (HUVEC) against oxidative damage by inducing the expression of heme oxygenase-1 (HO-1) and to explore the underlying mechanism. METHODS: The cellular protection of chlorophyllin against oxidative damage was detected by cell-survival assay with flow cytometry. The level of free radicals was detected directly by electron spin resonance spectra. The induced expression of HO-1 was shown by RT-PCR, Western blot, immunofluorescence confocal laser microscopy and enzymatic activity test. Whether the activation of PI3K/Akt pathway was involved was detected by Western blot. RESULTS: Chlorophyllin could protect HUVEC against oxidative damage caused by H2O2 via scavenging the excessive free radicals. Chlorophyllin treatment could induce expression of HO-1 in a dose- and time-dependent manner. The activation of PI3K/Akt pathway was required in the induction of HO-1. LY294002, the specific inhibitor of PI3K, could suppress the activation of PI3K/Akt and the induced expression of HO-1 in a dose-dependent manner. CONCLUSIONS: Chlorophyllin shows cellular protection against oxidative damage by counteracting the excessive free radicals. Up-regulation of HO-1 expression plays a pivotal role in the protection of chlorophyllin, while the activation of PI3K/Akt signaling pathway is required in the induction of HO-1.
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Clorofilídeos/farmacologia , Sequestradores de Radicais Livres/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Cromonas/farmacologia , Heme Oxigenase-1 , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Type 2 diabetes mellitus (T2DM) and mood disorders share pathophysiological commonalities in the central nervous system. The purpose of this study was to investigate the alterations in amygdala-based emotional processing circuits in T2DM patients with depressive mood using resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: T2DM patients with depressive mood (n = 25), T2DM patients without depressive mood (n = 28) and matched healthy controls (n = 25) underwent neuropsychological testing and rs-fMRI scanning. A seed-based correlation analysis was conducted to reveal the altered functional connectivity (FC) of the amygdala. The bilateral amygdala FC was compared among the three groups. Pearson correlation analyses were performed in a voxel-wise manner to investigate the relationship between amygdala FC and the clinical characteristics. RESULTS: The depressed T2DM patients exhibited the worst performance on the neuropsychological tests among the three groups. Compared to the non-depressed T2DM patients, the depressed T2DM patients showed decreased amygdala FC in the cingulate cortex, inferior frontal gyrus, fusiform gyrus, and precentral gyrus. Moreover, the amygdala FC in the cingulate cortex was associated with the Self-Rating Depression Scale (SDS) score in the T2DM patients. LIMITATIONS: Cross-sectional design. CONCLUSIONS: The current study revealed the cognitive changes and alterations in the amygdala-cingulate functional disconnections in T2DM patients with depressive mood, which will advance the understanding of the neural mechanisms underlying depression in T2DM patients.
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Tonsila do Cerebelo/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Transtornos do Humor/fisiopatologia , Vias Neurais/fisiopatologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Mapeamento Encefálico , Estudos Transversais , Depressão/fisiopatologia , Emoções/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Testes Neuropsicológicos , Córtex Pré-Frontal/fisiopatologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologiaRESUMO
Previous studies have indicated that the pathogenesis of diabetes differs between obese and lean patients. We investigated whether newly diagnosed Chinese diabetic patients with different body mass indices (BMIs) have different glycemic variability, and we assessed the relationship between BMI and glycemic variability. This was a cross-sectional study that included 169 newly diagnosed and drug-naïve type 2 diabetic patients (mean age, 51.33 ± 9.83 years; 110 men). The clinical factors and results of the 75-g oral glucose tolerance test were all recorded. Glycemic variability was assessed using continuous glucose monitoring. Compared with overweight or obese patients (BMI ≥ 24 kg/m2), underweight or normal-weight patients (BMI < 24 kg/m2) had higher levels of blood glucose fluctuation parameters, particularly in terms of mean amplitude of glycemic excursion (MAGE 6.64 ± 2.38 vs. 5.67 ± 2.05; P = 0.007) and postprandial glucose excursions (PPGEs) (PPGE at breakfast, 7.72 ± 2.79 vs. 6.79 ± 2.40, P = 0.028; PPGE at lunch, 5.53 ± 2.70 vs. 5.07 ± 2.40, P = 0.285; PPGE at dinner, 5.96 ± 2.24 vs. 4.87 ± 2.50, P = 0.008). BMI was negatively correlated with glycemic variability (r = -0.243, P = 0.002). On multiple linear regression analyses, BMI (ß = -0.231, P = 0.013) and Insulin Secretion Sensitivity Index-2 (ß = -0.204, P = 0.048) were two independent predictors of glycemic variability. In conclusion, lower BMI was associated with increased glycemic variability, characterized by elevated PPGEs, in newly diagnosed Chinese type 2 diabetic patients.
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INTRODUCTION: The objective of this study was to investigate the effect of adding exenatide to continuous subcutaneous insulin infusion (CSII) therapy on the precise insulin doses required by type 2 diabetic patients to maintain glycemic control. METHODS: This was a single-center, randomized, controlled, open-label trial. Uncontrolled T2D patients were recruited between March 2010 and November 2011 at Nanjing First Hospital, China. Subjects were randomly assigned (1:1) to either an exenatide add-on to CSII group or a CSII therapy only (i.e., control) group (n = 18, respectively) for 5 weeks. Patients were subjected to 3 days of continuous glucose monitoring (CGM) during the screening period and after therapy. The precise insulin doses, the times taken by the patients to achieve euglycemic control, and the mean amplitude of glycemic excursion (MAGE) at the endpoint were compared between the two groups. The primary endpoint was precise insulin dose differences between groups from baseline to the endpoint. RESULTS: A total of 36 subjects were admitted as inpatients. Patients in the exenatide add-on therapy group needed less insulin titration time to achieve glycemic control (3.67 ± 1.33 vs. 4.78 ± 1.00 days, P = 0.028) and significantly lower bolus insulin doses than the control group at the endpoint (total bolus, 0.13 ± 0.03 vs. 0.17 ± 0.04 U/kg, P = 0.02, breakfast bolus, 0.05 ± 0.01 vs. 0.06 ± 0.01 U/kg, P = 0.01, lunch bolus, 0.04 ± 0.01 vs. 0.06 ± 0.01 U/kg, P = 0.01, dinner bolus, 0.04 ± 0.01 vs. 0.05 ± 0.01 U/kg, P = 0.01, respectively). Moreover, the CGM data showed that patients in the exenatide add-on therapy group exhibited a significant reduction in MAGE as compared to the control group (2.96 ± 1.14 vs. 4.21 ± 1.39 mmol/L, P = 0.012). CONCLUSION: Our data suggest that adding exenatide therapy to CSII therapy leads to an improvement in glycemic excursions and the use of smaller bolus insulin doses. TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier, ChiCTR-PPR-15007045.
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To define the features of glycemic variations in drug naïve type 2 diabetic (T2D) patients with different HbA1c values using continuous glucose monitoring (CGM), a total of 195 drug naïve T2D patients were admitted. The subjects were divided into the following groups: lower HbA1c values (≤8%), moderate HbA1c values (>8% and ≤10%), and higher HbA1c values (>10%). The patients underwent oral glucose tolerance tests and were then subjected to 3-day CGM. The primary endpoint was the differences in the 24-hr mean amplitude of glycemic excursions (MAGE) in patients with different HbA1c values. Patients with higher HbA1c values had larger MAGEs than those in the moderate and lower groups (7.44 ± 3.00 vs. 6.30 ± 2.38, P < 0.05, 7.44 ± 3.00 vs. 5.20 ± 2.35, P < 0.01, respectively). The 24-hr mean glucose concentrations increased incrementally in the patients with lower, moderate and higher HbA1c values. Moreover, the patients with higher HbA1c values exhibited higher peak glucose concentrations and prolongation in the time to peak glucose. Patients with higher HbA1c values had larger MAGE compared with those with lower and moderate HbA1c values. Our data indicated patients with higher HbA1c values should receive special therapy aimed at reducing the larger glycemic variations.
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Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/metabolismo , Automonitorização da Glicemia , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The aim of this study was to compare the safety and intra-individual contrast enhancement of low-osmolar monomeric iohexol and the iso-osmolar dimeric iodixanol in body computed tomography (CT) scanning. METHODS: In this single center, double-blind, prospective study, a total of 2000 consecutive patients undergoing adult body CT scanning were prospectively enrolled, with 1000 patients assigned to iodixanol and 1000 patients assigned to iohexol. In both groups, the contrast medium was injected at the rate of 3.5 ml/s. Subjective assessment of image quality for each image was determined using a 3-grading scale by three reviewers. Patients were monitored with questioning and vital signs before injection, immediately after injection, and at 24 and 48 h. Extensive laboratory evaluation also was performed. RESULTS: Laboratory results showed no significant difference across groups. There were also no detectable differences in image quality between the two contrast groups in this study. The total adverse reactions occurred in less than 1 % of individuals receiving iodixanol comparing to 2.5 % in iohexol group (P < 0.05). Among them, only 0.7 % patients injecting iodixanol suffered immediate events, comparing to 2 % patients in iohexol group. In all, 0.2 % patients with iodixanol and 0.5 % with iohexol had late allergic reaction. Further, No deaths occurred in any of the two groups. CONCLUSIONS: The iso-osmolar iodixanol provides image quality compared with that of iohexol, with lower incidence of adverse events.
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MicroRNAs, which can post-transcriptionally regulate gene expression by binding to the 3'-untranslated regions of the mRNAs, have been found to be the critical regulators of the development and progression of hepatocellular carcinoma (HCC). The present study demonstrated for the first time that microRNA-616 (miR-616) was markedly upregulated in HCC tissues, and was associated with the recurrence and metastasis of HCC. Elevated level of miR-616 was correlated with adverse clinicopathological features and poor prognosis of HCC patients. Gain- and loss-of-function studies revealed that miR-616 could potentiate the migration, invasion and the epithelial-mesenchymal transtion (EMT) phenotype of HCC cells. Phosphatase and tensin homolog (PTEN), the predicted target of miR-616 by bioinformatics analysis, was confirmed as a direct downstream target of miR-616 through western blotting, luciferase reporter and immunohistochemical assays. Furthermore, we demonstrated that miR-616 exerted the promoting effects on EMT and metastatic ability of HCC cells through suppressing PTEN expression. Based on these results, we conclude that miR-616 is a promising prognostic biomarker of HCC and targeting miR-616 may be a potential option to prevent the progression of HCC.
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Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Invasividade Neoplásica , Prognóstico , Regulação para CimaRESUMO
BACKGROUND: To investigate whether saxagliptin add-on therapy to continuous subcutaneous insulin infusion (CSII) further improve blood glycemic control than CSII therapy in patients with newly diagnosed type 2 diabetes (T2D). METHODS: This was a single-center, randomized, control, open-labeled trial. Newly diagnosed T2D patients were recruited between February 2014 and December 2015. Subjects were divided into saxagliptin add-on therapy to CSII group (n = 31) and CSII therapy group (n = 38). The treatment was maintained for 4 weeks. Oral glucose tolerance test was performed at baseline. Serum samples were obtained before and 30 and 120âminutes after oral administration for glucose, insulin, and C-peptide determination. Continuous glucose monitoring (CGM) was performed before and endpoint. RESULTS: A total of 69 subjects were admitted. After 4-week therapy, CGM data showed that patients with saxagliptin add-on therapy exhibited further improvement of mean amplitude glycemic excursion (MAGE), the incremental area under curve of plasma glucose >7.8 and 10âmmol/L compared with that of control group. In addition, the hourly mean blood glucose concentrations, especially between 0000 and 0600 in patient with saxagliptin add-on therapy, were significantly lower compared with that of the control patients. Furthermore, patients in saxagliptin add-on group needed lower insulin dose to maintain euglycemic control. In addition, severe hypoglycemic episode was not observed from any group. CONCLUSION: Saxagliptin add-on therapy to insulin had the ability of further improve blood glycemic controlling, with lower insulin dose required by patients with T2D to maintain euglycemic controlling.
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Adamantano/análogos & derivados , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptídeos/administração & dosagem , Insulina/administração & dosagem , Adamantano/administração & dosagem , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Inibidores da Dipeptidil Peptidase IV/administração & dosagem , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/administração & dosagem , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Human telomerase reverse transcriptase (hTERT) is upregulated in most cancer cell types as well in immortalized cells. The underlying mechanism for such upregulation, however, remains largely unknown. We report here that bile acids under acidified media increase hTERT expression via c-myc activation in primary human gastric cancer cell lines. Human gastric cancer MKN28, MGC803 and SGC7901 cells were treated with 100 µM deoxycholic acid (DCA) or chenodeoxycholic acid (CDCA) with or without acidified media in the presence or absence of the c-myc inhibitor 10058-F4 for 24 h. hTERT and c-myc protein levels were determined by western blot analysis. hTERT and c-myc mRNA levels were determined by RT-PCR. The promoter activities of hTERT and c-myc transcription were determined using promoter reporter luciferase assays for both. Telomerase enzyme activity was analyzed by stretch PCR. hTERT mRNA and protein levels were significantly increased by bile acids in acidified media and were accompanied with enhanced telomerase activity. No changes were found at a pH of 7.0 or with acidified media alone. Similarly, the mRNA and protein levels of c-myc were also increased by bile acids in acidified media but not at a pH of 7.0 or with acidified media alone. Importantly, pharmacologic inhibition of c-myc using 10058-F4 prevented hTERT induction by DCA or CDCA in gastric cancer cells under acidic conditions. Bile acids (DCA and CDCA) under acidic conditions increased hTERT expression in human gastric cancer cells by activation of c-myc transcription. This suggests that acidified bile acids may promote tumorigenesis and affect cell ageing via telomerase activation.
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Ácidos e Sais Biliares/administração & dosagem , Proteínas Proto-Oncogênicas c-myc/biossíntese , Neoplasias Gástricas/tratamento farmacológico , Telomerase/biossíntese , Ácidos e Sais Biliares/metabolismo , Linhagem Celular Tumoral , Ácido Quenodesoxicólico/administração & dosagem , Ácido Desoxicólico/administração & dosagem , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/efeitos dos fármacos , Neoplasias Gástricas/genética , Telomerase/antagonistas & inibidores , Telomerase/genética , Tiazóis/administração & dosagem , Ativação Transcricional/efeitos dos fármacosRESUMO
Caudalrelated homeobox transcription factor 2 (CDX2) is a transcription factor, which is specifically expressed in the adult intestine. It is essential for the development and homeostasis of the intestinal epithelium and its functions as a tumor suppressor have been demonstrated in the adult colon. The present study aimed to examine the inhibitory effects of the overexpression of CDX2 on subcutaneouslytransplanted tumors, derived from LoVo colon cancer cells, in nude mice, and to provide experimental evidence for the biotherapy of colon cancer. A pEGFPC1CDX2 eukaryotic expression vector was transfected into the LoVo cells via lipofection, and LoVo cells stablyexpressing CDX2 (pEGFPC1CDX2 cells) were obtained using G418 selection. A nude mouse subcutaneouslytransplanted tumor model was established by inoculating the nude mice with the pEGFPC1CDX2 cells, and the effects of overexpression of CDX2 on transplanted tumor growth in the LoVo cells were observed. Western blotting results demonstrated that the protein expression of CDX2 in the LoVo cells was higher in the pEGFPC1CDX2 cell group, compared with that in the pEGFPC1 cell group and the untreated cell group. At 20 days postinoculation with either pEGFPC1CDX2 or pEGFPC1, the transplanted tumor masses were significantly lower in the pEGFPC1CDX2 group, compared with those in the pEGFPC1 and untreated groups. Immunohistochemistry revealed that the expression levels of CDX2 and matrix metalloproteinase2 (MMP2) were detected in each group, and the protein expression of CDX2 was increased in the tumor tissues from the nude mice in the pEGFPC1CDX2 group. However the expression of MMP2 was downregulated in the tumor tissues of the nude mice in the pEGFPC1CDX2 group. Taken together, these data suggested that pEGFPC1CDX2 cells exhibited suppressed tumor growth in vivo. Overexpression of CDX2 was observed in transplanted tumors in the pEGFPC1CDX2 group, and the gene expression of MMP2 was reduced. These results indicate that CDX2 inhibited the growth of colorectal tumor cells, possibly by downregulating the gene expression.
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Neoplasias Colorretais/metabolismo , Proteínas de Homeodomínio/metabolismo , Animais , Fator de Transcrição CDX2 , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Camundongos Nus , Transplante de Neoplasias , Carga TumoralRESUMO
Experiments were performed on male Sprague-Dawley (SD) rats anesthetized with a mixture of urethane and chloralose. A rat model of acute myocardial ischemia (AMI) was made by ligation of the left anterior descending branch of the coronary artery (LAD). After the LAD ligation, the ischemia area of the left ventricular wall became somewhat pale immediately. Under a light microscope, the pathological examination revealed that all the cells were swollen and in red color when the cardiac section was stained with hematoxylin basic fuchsin picric acid (HBFP), which indicated a typical change in the myocardial ischemia. In the AMI model, it was found that cardiac functions were markedly attenuated, such as decreases in the heart rate (HR), mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), maximal rate for left ventricular pressure rising and declining (+/-dp/dt(max)), velocity of contractile element (V(CE)) and total area of cardiac force loop (L(0)), and an increase in the left ventricular end diastolic pressure (LVEDP). In such AMI rats, application of electroacupuncture (EA) at "Neiguan" acupoints (Pe 6) for 20 min could obviously improve the above-mentioned cardiac functions. After microinjection of nitro-L-arginine (L-NNA), an inhibitor of nitric oxide synthase (NOS), was made into the rostral ventrolateral medulla (RVLM), the curative effect of EA on myocardial ischemia was reduced significantly or abolished, while after microinjection of normal saline of the same volume was made into the RVLM, the improving effect of EA remained. These results suggest that the effect of EA on myocardial ischemia is possibly mediated by the nitric oxide (NO) in the RVLM.