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31.
The role of the paraoxonase (PON1) codon 192 polymorphism [glutamine (Q)/arginine (R)] in coronary artery disease (CAD) is controversial. The aim of the present study was to evaluate whether the PON1 gene polymorphism is an independent risk factor for severity of coronary artery disease in patients from west of Iran. The PON1-Arg-192 genotypes were detected by PCR-RFLP in 414 individuals undergoing their first coronary angiography. Patients were placed into one of two groups: CAD and control without CAD or diabetes. The frequency of PON1-Arg-192 allele was significantly higher in the CAD (23.4 vs. 16%, P = 0.032) than in the control group and there was a higher risk of developing CAD (OR = 1.6, P = 0.02). In addition, this difference remained significant after adjustment for without history of diabetes (OR = 1.47, P = 0.048), presence of normolipidemia and absence of history of blood pressure (OR = 1.4, P = 0.05). This result indicated PON1-Arg-192 allele is a risk factor of CAD also when correcting for conventional risk factors. We found a significant association between the PON1-Arg-192 genotype (QR + RR) and the extent of CAD in CAD patients and CAD subjects without diabetes, represented by the increased frequency of three-vessel disease with OR = 1.49, P = 0.046; χ2 = 3.82, P = 0.048 and OR = 1.46, P = 0.05; χ2 = 3.48, P = 0.051, respectively. The CAD patients carrying PON1-Arg-192 genotype (QR + RR) had lower plasma HDL-C level (P = 0.019) and higher plasma LDL-C(P = 0.01) and TG(P = 0.05). Our results indicated that PON1-Arg-192 allele can be important independent risk factor of CAD in a west population of Iran, with carriers of PON1-Arg-192 having an increased frequency of three-vessel disease and also having a distinct plasma lipids profile. Larger collaborative studies are needed to confirm these results.  相似文献   
32.
Mitogen-activated protein kinase (MAPK) signaling pathways organize a great constitution network that regulates several physiological processes, like cell growth, differentiation, and apoptotic cell death. Due to the crucial importance of this signaling pathway, dysregulation of the MAPK signaling cascades is involved in the pathogenesis of various human cancer types. Oxidative stress and DNA damage are two important factors which in common lead to carcinogenesis through dysregulation of this signaling pathway. Reactive oxygen species (ROS) are a common subproduct of oxidative energy metabolism and are considered to be a significant physiological modulator of several intracellular signaling pathways including the MAPK pathway. Studies demonstrated that the MAP kinases extracellular signal-regulated kinase (ERK) 1/2 and p38 were activated in response to oxidative stress. In addition, DNA damage is a partly common circumstance in cell life and may result in mutation, cancer, and even cell death. Recently, accumulating evidence illustrated that the MEK/ERK pathway is associated with the suitable performance of cellular DNA damage response (DDR), the main pathway of tumor suppression. During DDR, the MEK/ERK pathway is regularly activated, which contributes to the appropriate activation of DDR checkpoints to inhibit cell division. Therefore, the aim of this review is to comprehensively discuss the critical function of MAPK signaling in oxidative stress, DNA damage, and cancer progression.  相似文献   
33.
Ternary blends with broad spectral absorption have the potential to increase charge generation in organic solar cells but feature additional complexity due to limited intermixing and electronic mismatch. Here, a model system comprising the polymers poly[5,5‐bis(2‐butyloctyl)‐(2,2‐bithiophene)‐4,4‐dicarboxylate‐alt‐5,5‐2,2‐bithiophene] (PDCBT) and PTB7‐Th and PC70BM as an electron accepting unit is presented. The power conversion efficiency (PCE) of the ternary system clearly surpasses the performance of either of the binary systems. The photophysics is governed by a fast energy transfer process from PDCBT to PTB7‐Th, followed by electron transfer at the PTB7‐Th:fullerene interface. The morphological motif in the ternary blend is characterized by polymer fibers. Based on a combination of photophysical analysis, GIWAXS measurements and calculation of the intermolecular parameter, the latter indicating a very favorable molecular affinity between PDCBT and PTB7‐Th, it is proposed that an efficient charge generation mechanism is possible because PTB7‐Th predominantly orients around PDCBT filaments, allowing energy to be effectively relayed from PDCBT to PTB7‐Th. Fullerene can be replaced by a nonfullerene acceptor without sacrifices in charge generation, achieving a PCE above 11%. These results support the idea that thermodynamic mixing and energetics of the polymer–polymer interface are critical design parameter for realizing highly efficient ternary solar cells with variable electron acceptors.  相似文献   
34.

Objective

To investigate the effect of H2O2 on the migration and antioxidant defense of mesenchymal stem cells (MSCs) and the neurotrophic effects of H2O2-treated MSCs on spinal cord injury (SCI).

Results

Sublethal concentrations of H2O2 decreased cell migration and expression of CXCR4 and CCR2 as well as Nrf2 expression in MSCs. In the second phase, transplantation of treated and untreated MSCs to SCI caused minor changes in locomotor dysfunction. There was a significantly difference between cell-treated and spinal cord injury groups in expression of BDNF (brain-derived neurotrophic factor). Transplantation of H2O2-treated cells caused an increase in BDNF expression compared to non-treated cells.

Conclusion

Transplantation of H2O2-treated stem cells may have protective effects against SCI through by increasing neurotrophic factors.
  相似文献   
35.
Kisspeptin (Kp) expression in testis has caused most of the recent research surveying its functional role in this organ. This peptide influences spermatogenesis and sperm capacitation, so it is considered as a regulator of reproduction. Kp roles exert through hypothalamic/pituitary/gonadal axis. We aimed to evaluate direct roles for Kp on proliferation and differentiation of spermatogonial cells (SCs) when the cells are cocultured with somatic cells. Somatic cells and SCs were isolated from adult azoospermic and newborn mice and then enriched using a differential attachment technique. After the evaluation of identity and colonization for SCs, the cells were cocultured with somatic cells, and three doses of Kp (10−8-10−6 M) was assessed on proliferation (through evaluation of MVH and ID4 markers) and differentiation (via evaluation of c-Kit and SCP3, TP1, TP2, and, Prm1 markers) of the coculture system. Investigations were continued for four succeeding weeks. At the end of each level of testosterone in the culture media was also evaluated. We found positive influence from Kp on proliferative and differentiative markers in SCs cocultured with somatic cells. These effects were dose-dependent. There was no effect for Kp on testosterone level. From our findings, we simply conclude that Kp as a neuropeptide for influencing central part of reproductive axis could also positively affect peripheral processes related to spermatogenesis without having an effect on steroidogenesis.  相似文献   
36.
The fruit essential oils of Heracleum persicum, H. rechingeri, H. gorganicum, H. rawianum, H. pastinacifolium, and H. anisactis from Iran were obtained by hydrodistillation and characterized by GC‐FID and GC/MS analyses. The oils of the six species were compared to determine the similarities and differences among their compositions. Overall, 36 compounds were identified in the fruit oils, accounting for 92.40–96.74% of the total oil compositions. Aliphatic esters constituted the main fraction of the oils (86.61–94.31%), with octyl acetate and hexyl butyrate as the major components. The oil compositions of species belonging to section Pubescentia (H. persicum, H. gorganicum, and H. rechingeri) were discriminated by equally high contents of both octyl acetate (13.84–20.48%) and hexyl butyrate (17.73–38.36%). On the other hand, the oils of H. rawianum, H. pastinacifolium and H. anisactis, belonging to section Wendia, showed lower hexyl butyrate contents (3.62–6.6%) and higher octyl acetate contents (48.71–75.36%) than the former. Moreover, isoelemicin was identified at low amounts (0.10–2.51%) only in the oils of the latter species. The differences in the oil composition among the six species were investigated by hierarchical cluster and principal component analyses, which indicated that the oil composition confirmed well the taxonomical classification based on the morphological and botanical data, and, thus, may provide a reliable marker to discriminate Heracleum species at the intersectional level.  相似文献   
37.
38.
We have previously shown that butyrylcholinesterase-K (BCHE-K, G1615A/Ala539Thr) variant increases the risk of coronary artery disease (CAD). In addition, we have found that the presence of APOE-ε4 allele augments the risk of CAD in patients with type II diabetes mellitus (T2DM/CAD). Here we explored the concomitant presences of two alleles of the BCHE-K and APOE-ε4 in increasing the risk of CAD or diabetes in T2DM patients with or without CAD and CAD patients without T2DM. This case–control study comprised 631 subjects undergoing their first coronary angiography. They were matched and randomly assigned into four groups: type II diabetic patients with no sign of CAD (T2DM), type II diabetic patients with CAD/ND (T2DM/CAD), CAD patients with no sign of diabetes (CAD/ND), and healthy individuals (NCAD/ND). BCHE-K variant and APOE genotypes were detected by PCR-RFLP and serum lipid level was measured enzymatically. We found that BCHE-K and APOE-ε4 allele act synergistically to increase the risk of CAD in both T2DM, non-diabetic and total CAD (TCAD = T2DM/CAD + CAD/ND) individuals. The level of synergy 1.5 and 1.2 fold are higher in CAD patients (OR = 4.5; P = 0.011) with T2DM than the non-diabetic CAD patients (OR = 3.07; P = 0.024) and TCAD patients (OR = 3.74; P = 0.018), respectively. The CAD subjects with and without T2DM and TCAD patients carrying both APOE-ε4 allele and BCHE-K had significantly lower plasma HDL-C (P values = 0.008, 0.047, and 0.036, respectively) and higher plasma LDL-C (P values = 0.025, 0.048, and 0.04, respectively), than that of the control carriers both APOE-ε4 and BCHE-K. We have found that BCHE-K and APOE-ε4 allele not only act synergistically to increase the risk of CAD, particularly in T2DM subjects in population from western Iran, who have high levels of LDL-C and low levels of HDL-C, suggesting that a specific therapeutic intervention should be considered for these particular groups of patients.  相似文献   
39.
International Journal of Peptide Research and Therapeutics - Melittin is a 26 amino acid amphipathic peptide, the main part of a bee venom. It has been confirmed that melittin can act against a...  相似文献   
40.
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