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31.
Background : Cardiac contusion (CC) is a known complication of blunt trauma to the chest. There have been debates about its true incidence and there are different reports which claim that it occurs in less than 10% to more than 70% of patients. The goal of this study is to estimate the incidence of CC in patients with severe blunt chest trauma (SBCT) using transthoracic echocardiography (TTE).Methods : After defining inclusion and exclusion criteria, all cases with clinical evidences of SBCT from February 2010 until October 1011 were included in this study. Patients were assessed using electrocardiography (ECG) and transthoracic echocardiography (TTE). Transient echocardiography changes, including wall motion abnormalities, valvular or papillary muscle dysfunction, pericardial effusion or tamponade, free wall rupture and interatrial/interventricular septum defects, were considered to be abnormal and trauma-related.Results : A total of 110 patients were assessed for CC. Fifty-two trauma-related echocardiography changes in 47 patients were observed, in which 34 cases had simultaneous transient ECG changes. The estimated incidence of CC in these subjects was calculated to be 23.38% and 16.19%, respectively. There was a statistically significant relationship between the presence of both echocardiography changes and ECG abnormalities, and those subjects without ECG changes (P = 0.03). As we evaluated stable patients without any cardiac-related clinical manifestations and TTE was chosen as our diagnostic modality, we claim that the true incidence must be higher.Conclusions : We believe that a comparison of our findings with those presented in the literature shows that the actual incidence of CC in blunt chest trauma is underestimated. 相似文献
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Study of the Cytotoxic and Bactericidal Effects of Sila‐substituted Thioalkyne and Mercapto‐thione Compounds based on 1,2,3‐Triazole Scaffold 下载免费PDF全文
Hanieh Mousazadeh Morteza Milani Nosratollah Zarghami Effat Alizadeh Kazem D. Safa 《Basic & clinical pharmacology & toxicology》2017,121(5):390-399
A series of sila‐organosulphur compounds containing 1,2,3‐triazole cores were screened for their cytotoxic activity on human breast cancer cell line MCF‐7. Most of the tested compounds exhibited moderate‐to‐good activity against the cancer cells. Especially, the compound 4‐((2‐(trimethylsilyl)ethynylthio)methyl)‐1‐benzyl‐1H‐1,2,3‐triazole ( 3a) from series of sila‐substituted thioalkyne 1,2,3‐triazoles (STATs) and the compounds 3‐(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)‐1‐mercapto‐1,1‐bis(trimethylsilyl)propane‐2‐thione ( 4a) and 1‐mercapto‐1,1‐bis(trimethylsilyl)‐3‐(1‐phenethyl‐1H‐1,2,3‐triazol‐4‐yl)propane‐2‐thione ( 4e) from series of sila‐substituted mercapto‐thione 1,2,3‐triazoles (SMTTs) exhibited promising cytotoxicity against MCF‐7 with IC50 values of 35.17, 32.63 and 30.3 μg/mL, respectively. In addition, the possible mechanisms for inhibition of cell growth and induction of apoptotic cell death were explored by DAPI staining, cell cycle analysis and qRT‐PCR. The synthetic compounds were evaluated for their in vitro antibacterial activities, and as a result, the most prominent effects were observed for 3e and 4e . Especially, 3e was found to be quite active against all the tested strains with the MIC values ranging from 15 to 62 μg/mL, except P. aeruginosa. The results of the time‐kill assay suggested that the compound of 3e completely inhibited the growth of both gram‐negative bacteria, A. baumannii, and gram‐positive bacteria, S. aureus. In addition, SEM analysis confirmed morphostructural damage of the bacteria. Our findings could be applicable for developing dual‐targeting anticancer/antibacterial therapeutics. 相似文献
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Vahid Khori Ali Mohammad Alizadeh Zohre Gheisary Sadaf Farsinejad Farrokh Najafi Solmaz Khalighfard Fatemeh Ghafari Maryam Hadji Hamid Khodayari 《Lasers in medical science》2016,31(9):1775-1782
Low-level laser therapy (LLLT) is a form of photon therapy which can be a non-invasive therapeutic procedure in cancer therapy using low-intensity light in the range of 450–800 nm. One of the main functional features of laser therapy is the photobiostimulation effects of low-level lasers on various biological systems including altering DNA synthesis and modifying gene expression, and stopping cellular proliferation. This study investigated the effects of LLLT on mice mammary tumor and the expression of Let-7a, miR155, miR21, miR125, and miR376b in the plasma and tumor samples. Sixteen mice were equally divided into four groups including control, and blue, green, and red lasers at wavelengths of 405, 532, and 632 nm, respectively. Weber Medical Applied Laser irradiation was carried out with a low power of 1–3 mW and a series of 10 treatments at three times a week after tumor establishment. Tumor volume was weekly measured by a digital vernier caliper, and qRT-PCR assays were performed to accomplish the study. Depending on the number of groups and the p value of the Kolmogorov-Smirnov test of normality, a t test, a one-way ANOVA, or a non-parametric test was used for data analyses, and p?<?0.05 was considered to be statistically significant. The average tumor volume was significantly less in the treated blue group than the control group on at days 21, 28, and 35 after cancerous cell injection. Our data also showed an increase of Let-7a and miR125a expression and a decrease of miR155, miR21, and miR376b expression after LLLT with the blue laser both the plasma and tumor samples compared to other groups. It seems that the non-invasive nature of laser bio-stimulation can make LLLT an attractive alternative therapeutic tool. 相似文献
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Sánchez E Alizadeh BZ Valdigem G Ortego-Centeno N Jiménez-Alonso J de Ramón E García A López-Nevot MA Wijmenga C Martín J Koeleman BP 《Human immunology》2007,68(7):610-615
The aim of the study was to test MYO9B gene polymorphisms for association with three autoimmune diseases, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and celiac disease (CD), in a Spanish population. We analyzed three SNPs (rs2305767, rs1457092, and rs2305764) in a case-control cohort composed of 349 SLE patients, 356 RA patients, 90 CD patients, and 345 healthy controls. All three SNPs showed a consistent increased frequency of the A allele in SLE, RA, and CD patients compared with healthy controls. An association was observed between CD and rs2305764 (p=0.01, OR=2.3), between SLE and rs1457092 (p=0.002, OR=1.4), and between RA and rs1457092 (p=0.02, OR=1.3). The three autoimmune diseases combined showed significant association with rs1457092 and rs2305764 and with the AAA haplotype (p haplotype=0.005, OR=1.3). Our data demonstrate consistent association with the A allele and AAA haplotype of three SNPs in the MYO9B gene, which were previously reported to be associated with CD in the Dutch population. This suggests that genetic variation in MYO9B is associated with CD, SLE, and RA and that MYO9B is a general risk factor for autoimmunity. 相似文献
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Elnaz Mohammad Alizadeh Majid Mahdavi Forough Jenani Fard Solmaz Chamani Fereshteh Farajdokht 《Toxicology mechanisms and methods》2018,28(8):622-629
Oxidative stress has a causative role in ischemic reperfusion-induced cell death. Evidence has shown that metformin is capable to reduce ischemic reperfusion injuries. The current study investigated the effect of metformin on ischemia/reperfusion-induced apoptosis in PC12 cells by evaluation of Bcl-2 family proteins expression. Cells were exposed to a time-dependent in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) injury and then treated with metformin. The intracellular reactive oxygen species (ROS) levels were measured. Western blotting was used to examine the expression of anti- and pro-apoptotic proteins. Moreover, the number of apoptotic cell death was evaluated by TUNEL assay. Our results showed that metformin attenuated ROS generation, downregulated pro-apoptotic BAX expression, and upregulated expression of the Bcl-2 protein in the PC12 cells. Moreover, metformin reduced cell death under OGD/R condition which was confirmed by lower apoptotic cell death in the TUNEL assay. These findings suggest that neuroprotective effect of metformin on OGD/R-induced cell death is possibly mediated by inhibition of ROS-induced apoptosis pathway. 相似文献
38.
Many endodontically-treated teeth require quick, simple, low-cost restorations. This study evaluated the effect of horizontal pins and flowable composites on the fracture resistance of endodontically-treated maxillary premolars directly restored with resin composite. In this in vitro study, 64 intact human maxillary premolars, extracted for orthodontic reasons, were randomly divided into four groups of 16. Standard access cavities were prepared in such a way that the buccal cusp had a buccolingual thickness of 3 mm measured at the height of contour. The palatal cusp was reduced to 1.5 mm coronal to CEJ. The specimens were prepared as follows: Group 1: resin composite restoration without horizontal self-threading pins or flowable composite (control group). Group 2: resin composite restoration without horizontal self-threading pins but with a 2 mm thickness of the flowable composite. Group 3: resin composite restoration with two horizontal self-threading pins in the buccal cusp but without flowable composite. Group 4: resin composite restoration with two horizontal self-threading pins in the buccal cusp and flowable composite with a thickness of 2 mm. Subsequent to thermocycling, all specimens were loaded to failure. The data were analyzed using a two-factor ANOVA test (alpha = 0.05). The maximum mean of fracture resistance was in Group 1 (632.86 +/- 119.46 N), and the minimum value was related to Group 3 (533.49 +/- 168.07 N). There was not a statistically significant difference between the groups (p > 0.05). Conclusion: Neither horizontal pin placement nor flowable composite had a significant effect on increasing the fracture resistance of endodontically-treated maxillary premolars restored with composite. 相似文献
39.
Up Regulation of Liver-enriched Transcription Factors HNF4a and HNF6 and Liver-Specific MicroRNA (miR-122) by Inhibition of Let-7b in Mesenchymal Stem Cells 下载免费PDF全文
40.
Genomic expression programs and the integration of the CD28 costimulatory signal in T cell activation 总被引:15,自引:0,他引:15 下载免费PDF全文