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121.
Shohreh Honarbakhsh Irina Suman-Horduna Lilian Mantziari Sabine Ernst 《Indian pacing and electrophysiology journal》2013,13(3):126-130
A 33-year old female with a background of Eisenmenger syndrome secondary to multiple congenital muscular ventricular septal defects (VSD) was admitted with a recent history of frequent intermittent palpitations. It was noted that she had an independent accelerated idioventricular rhythm (AIVR), with rates varying between 85-110 bpm, which exhibited a repetitive grouped beating pattern. Although generally perceived as benign, in this case this rhythm was drug refractory, was associated with significant compromise to cardiac filling and output and progressed to haemodynamically intolerable sustained ventricular tachyarrhythmia. Successful ablation was performed at the inferior aspect of the residual VSD, from within the Purkinje network. 相似文献
122.
Mohammad Foad Abazari Navid Nasiri Fatemeh Nejati Shohreh Zare Karizi Mojdeh Amini Faskhodi Ehsan Saburi Nasrin Aghapur Mohammad Reza Mahdavi Abdolreza Ardeshirylajimi Seyed Ehsan Enderami Fatemeh Soleimanifar 《Journal of cellular physiology》2020,235(5):4239-4246
Diabetes is one of the most common diseases in the world that is chronic, progressive, and costly, and causes many complications. Common drug therapies are not able to cure it, and pancreas transplantation is not responsive to the high number of patients. The production of the insulin producing cells (IPCs) from the stem cells in the laboratory and their transplantation to the patient's body is one of the most promising new approaches. In this study, the differentiation potential of the induced pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs) into IPCs was compared to each other while cultured on poly(lactic-co-glycolic) acid (PLGA)/polyethylene glycol (PEG) nanofibrous scaffold as a 3D substrate and tissue culture polystyrene (TCPS) as a 2D substrate. Although the expression level of the insulin, Glut2 and pdx-1 genes in stem cells cultured on 3D substrate was significantly higher than the stem cells cultured on 2D substrate, the highest expression level of these genes was detected in the iPSCs cultured on PLGA-PEG. Insulin and C-peptide secretions from differentiated cells were also investigated and the results showed that secretions in cultured iPSCs on the PLGA-PEG were significantly higher than cultured iPSCs on the TCPS and cultured MSCs on both PLGA-PEG and TCPS. In addition, insulin protein was also expressed in the cultured iPSCs on the PLGA-PEG significantly higher than cultured MSCs on the PLGA-PEG. It can be concluded that differentiation potential of iPSCs into IPCs is significantly higher than human MSCs at both 2D and 3D culture systems. 相似文献
123.
Hamid Reza Rahimi Manoochehr Rasouli Akram Jamshidzadeh Shohreh Farshad Mehdi Saberi Firoozi Ali Reza Taghavi Simin Kiany 《Microbiology and immunology》2013,57(6):455-462
124.
Azam Mortazavifar Heidar Raissi Mahnaz Shahabi 《Journal of biomolecular structure & dynamics》2013,31(18):4852-4862
AbstractIn this study, the adsorption of Hydroxyurea (HU) onto the inner and outer surfaces of boron nitride and carbon nanotubes (CNTs) was investigated using the density functional theory calculations and molecular dynamics (MDs) simulations in aqueous solution. The values of the adsorption energy show that HU molecule is preferentially adsorbed inside of boron nitride and CNTs with the molecular axis parallel to the tubes axis, which means that the cavity of nanotubes is favorable for encapsulation of this drug. Also, it was found that the HU/boron nitride nanotube (BNNT) system is more stable than the HU/CNT system. The stability of the complexes of HU/ BNNT attributed to the formation of the intermolecular hydrogen bonds between the H atoms of HU molecule and the N atoms of BNNT, which is confirmed by Bader’s quantum theory of atoms in molecules. The natural bond orbital analysis shows the charge transfers occur from HU molecule to nanotubes in all complexes. Moreover, the adsorption of HU molecule on the surfaces of the nanotubes was investigated by explicit water models. Also, the adsorption behavior of HU on the functionalized boron nitride and CNTs is investigated to design and develop new nanocarriers for biomedical applications. Furthermore, MDs simulations are examined in the presence of one and two drug molecules. The obtained results illustrate that the lowest value of Lennard–Jones (L–J) energy between drug and nanotubes exist in the simulation system with two drug molecules. 相似文献
125.
Nima Hosseini Jazani Mojtaba Karimzad Ebrahim Mazloomi Mohammad Sohrabpour Zuhair Muhammad Hassan Hojjat Ghasemnejad Shiva Roshan-Milani Shahram Shahabi 《Microbes and infection / Institut Pasteur》2010,12(5):382-388
We have previously demonstrated the adjuvant activity of naloxone (NLX), a general opioid antagonist, using a DNA vaccine for herpes simplex virus type 1. Here, the adjuvant activity of NLX has been evaluated using a heat-killed Listeria monocytogenes (HKLM) vaccine as a model for general immunization against intracellular bacteria. BALB/c mice were divided into three groups: the Vac group received the HKLM vaccine alone; the NLX–Vac group received the HKLM vaccine in combination with the adjuvant NLX; and the control group received phosphate buffered saline (PBS). Our results indicate that the administration of NLX as an adjuvant enhances the ability of the HKLM vaccine to increase lymphocyte proliferation, delayed type hypersensitivity, and skewing of the immune response toward a T-helper 1 (Th1) pattern. Additionally, combination of NLX with the HKLM vaccine improves protective immunity against L. monocytogenes. In conclusion, administration of NLX as an adjuvant for the HKLM vaccine can enhance cell-mediated immunity and shift the immune response to Th1. 相似文献
126.
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128.
Teige I Liu Y Issazadeh-Navikas S 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(6):3542-3553
We have previously investigated the physiological effects of IFN-beta on chronic CNS inflammation and shown that IFN-beta(-/-) mice develop a more severe experimental autoimmune encephalomyelitis than their IFN-beta(+/-) littermates. This result was shown to be associated with a higher activation state of the glial cells and a higher T cell cytokine production in the CNS. Because this state suggested a down-regulatory effect of IFN-beta on CNS-specific APCs, these results were investigated further. We report that IFN-beta pretreatment of astrocytes and microglia (glial cells) indeed down-modulate their capacity to activate autoreactive Th1 cells. First, we investigated the intrinsic ability of glial cells as APCs and report that glial cells prevent autoreactive Th1 cells expansion while maintaining Ag-specific T cell effector functions. However, when the glial cells are treated with IFN-beta before coculture with T cells, the effector functions of T cells are impaired as IFN-gamma, TNF-alpha, and NO productions are decreased. Induction of the T cell activation marker, CD25 is also reduced. This suppression of T cell response is cell-cell dependent, but it is not dependent on a decrease in glial expression of MHC class II or costimulatory molecules. We propose that IFN-beta might exert its beneficial effects mainly by reducing the Ag-presenting capacity of CNS-specific APCs, which in turn inhibits the effector functions of encephalitogenic T cells. This affect is of importance because activation of encephalitogenic T cells within the CNS is a prerequisite for the development of a chronic progressive CNS inflammation. 相似文献
129.
Mahmoudi T Arkani M Karimi K Safaei A Rostami F Arbabi E Pourhoseingholi MA Mohebbi SR Nikzamir A Romani S Almasi S Abbaszadeh M Vafaei M Zali MR 《Molecular biology reports》2012,39(5):5277-5282
Vitamin D appears to have anti-tumor activities in the large bowel. Our aim was to investigate whether -4817 G>A (rs2238136) polymorphism located at 5'-untranslated region (5'-UTR) of the human vitamin D receptor (VDR) gene was associated with colorectal cancer (CRC) risk. We conducted a case-control study and VDR genotypes, determined by Bpu10I restriction endonuclease digestion of PCR-amplified DNA, were performed on 327 cases with CRC and 327 controls. The distribution of VDR -4817 G>A genotypes and alleles differed significantly between cases with CRC and controls even after adjustment for confounding factors such as age, BMI, sex, and smoking status. Individuals carrying the "AA" genotype had a 2.09-fold increased risk compared with those with "GG" genotype (P?=?0.016, OR?=?2.09, 95% CI?=?1.15-3.78) and a 1.87-fold increased risk compared with those with "GG and GA" genotypes (P?=?0.033, OR?=?1.87, 95% CI?=?1.05-3.33) for CRC. Furthermore, the VDR "A" allele was significantly overrepresented in cases with CRC than controls (P?=?0.044; OR?=?1.28, 95% CI?=?1.01-1.63). Interestingly, the analysis of the SNP revealed that all these associations were stronger for women subjects than for all subjects combined. These data indicated for the first time a direct association between "AA" genotype of VDR gene -4817 G>A polymorphism and CRC, with a stronger association for female subjects. However, our findings remain to be confirmed in other populations. 相似文献
130.
WT Steegenga NJ de Wit MV Boekschoten N Ijssennagger C Lute S Keshtkar MM Grootte Bromhaar E Kampman LC de Groot M Müller 《BMC medical genomics》2012,5(1):38
ABSTRACT: BACKGROUND: By regulating digestion and absorption of nutrients and providing a barrier against the external environment the intestine provides a crucial contribution to the maintenance of health. To what extent aging-related changes in the intestinal system contribute to the functional decline associated with aging is still under debate. METHODS: Young (4 M) and old (21 M) male C57BL/6 J mice were fed a control low-fat (10E%) or a high-fat diet (45E%) for 2 weeks. During the intervention gross energy intake and energy excretion in the feces were measured. After sacrifice the small and large intestine were isolated and the small intestine was divided in three equal parts. Swiss rolls were prepared of each of the isolated segments for histological analysis and the luminal content was isolated to examine alterations in the microflora with 16S rRNA Q-PCR. Furthermore, mucosal scrapings were isolated from each segment to determine differential gene expression by microarray analysis and global DNA methylation by pyrosequencing. RESULTS: Digestible energy intake was similar between the two age groups on both the control and the high-fat diet. Microarray analysis on RNA from intestinal scrapings showed no marked changes in expression of genes involved in metabolic processes. Decreased expression of Cubilin was observed in the intestine of 21-month-old mice, which might contribute to aging-induced vitamin B12 deficiency. Furthermore, microarray data analysis revealed enhanced expression of a large number of genes involved in immune response and inflammation in the colon, but not in the small intestine of the 21-month-old mice. Aging-induced global hypomethylation was observed in the colon and the distal part of the small intestine, but not in the first two sections of the small intestine. CONCLUSION: In 21-month old mice the most pronounced effects of aging were observed in the colon, whereas very few changes were observed in the small intestine. 相似文献