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21.

In the recent past, huge emphasis has been given to the epigenetic alterations of the genes responsible for the cause of neurological disorders. Earlier, the scientists believed somatic changes and modifications in the genetic makeup of DNA to be the main cause of the neurodegenerative diseases. With the increase in understanding of the neural network and associated diseases, it was observed that alterations in the gene expression were not always originated by the change in the genetic sequence. For this reason, extensive research has been conducted to understand the role of epigenetics in the pathophysiology of several neurological disorders including Alzheimer’s disease, Parkinson’s disease and, Huntington’s disease. In a healthy person, the epigenetic modifications play a crucial role in maintaining the homeostasis of a cell by either up-regulating or down-regulating the genes. Therefore, improved understanding of these modifications may provide better insight about the diseases and may serve as potential therapeutic targets for their treatment. The present review describes various epigenetic modifications involved in the pathology of Parkinson’s Disease (PD) backed by multiple researches carried out to study the gene expression regulation related to the epigenetic alterations. Additionally, we will briefly go through the current scenario about the various treatment therapies including small molecules and multiple phytochemicals potent enough to reverse these alterations and the future directions for a better management of PD.

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23.
EcoHealth - Wild birds are important in the transmission of many zoonotic pathogens such as salmonella and avian influenza virus (AIV). The current study investigated the presence of bacterial and...  相似文献   
24.
International Journal of Peptide Research and Therapeutics - Cervical cancer is the second most common leading cause of women's death due to cancer worldwide, about 528,000 patients’...  相似文献   
25.

Auction designs have recently been adopted for static and dynamic resource provisioning in IaaS clouds, such as Microsoft Azure and Amazon EC2. However, the existing mechanisms are mostly restricted to simple auctions, single-objective, offline setting, one-sided interactions either among cloud users or cloud service providers (CSPs), and possible misreports of cloud user’s private information. This paper proposes a more realistic scenario of online auctioning for IaaS clouds, with the unique characteristics of elasticity for time-varying arrival of cloud user requests under the time-based server maintenance in cloud data centers. We propose an online truthful double auction technique for balancing the multi-objective trade-offs between energy, revenue, and performance in IaaS clouds, consisting of a weighted bipartite matching based winning-bid determination algorithm for resource allocation and a Vickrey–Clarke–Groves (VCG) driven algorithm for payment calculation of winning bids. Through rigorous theoretical analysis and extensive trace-driven simulation studies exploiting Google cluster workload traces, we demonstrate that our mechanism significantly improves the performance while promising truthfulness, heterogeneity, economic efficiency, individual rationality, and has a polynomial-time computational complexity.

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26.
Inflammatory cytokines exert different effects on hematopoietic stem cells (HSCs), lead to the development of various cell lineages in bone marrow (BM) and are thus a differentiation axis for HSCs. The content used in this article has been obtained by searching PubMed database and Google Scholar search engine of English-language articles (1995–2020) using “Hematopoietic stem cell,” “Inflammatory cytokine,” “Homeostasis,” and “Myelopoiesis.” Inflammatory cytokines are involved in the differentiation and proliferation of hematopoietic progenitors to compensate for cellular death due to inflammation. Since each of these cytokines differentiates HSCs into a specific cell line, the difference in the effect of these cytokines on the fate of HSC progenitors can be predicted. Inhibitors of these cytokines can also control the inflammatory process as well as the cells involved in leukemic conditions. In general, inflammatory signaling can specify the dominant cell line in BM to counteract inflammation and leukemic condition via stimulating or inhibiting hematopoietic progenitors. Therefore, detection of the effects of inflammatory cytokines on the differentiation of HSCs can be an appropriate approach to check inflammatory and leukemic conditions and the suppression of these cytokines by their inhibitors allows for control of homeostasis in stressful conditions.  相似文献   
27.

Background

The exact mechanisms of morphine-induced dependence and withdrawal symptoms remain unclear. In order to identify an agent that can prevent withdrawal syndrome, many studies have been performed. This study was aimed to evaluate the effect of gap junction blockers; carbenoxolone (CBX) or mefloquine (MFQ); on morphine withdrawal symptoms in male rat.Adult male Wistar rats (225 – 275 g) were selected randomly and divided into 10 groups. All groups underwent stereotaxic surgery and in order to induce dependency, morphine was administered subcutaneously) Sc) at an interval of 12 hours for nine continuous days. On the ninth day of the experiment, animals received vehicle or CBX (100, 400, 600 μg/10 μl/rat, icv) or MFQ (50, 100 and 200 μg/10 μl/rat, icv) after the last saline or morphine (Sc) injection. Morphine withdrawal symptoms were precipitated by naloxone hydrochloride 10 min after the treatments. The withdrawal signs including: jumping, rearing, genital grooming, abdomen writhing, wet dog shake and stool weight, were recorded for 60 minutes.

Results

Results showed that CBX and MFQ decreased all withdrawal signs; and the analysis indicated that they could attenuate the total withdrawal scores significantly.

Conclusion

Taking together it is concluded that gap junction blockers prevented naloxone-precipitated withdrawal symptoms.  相似文献   
28.
Enterotoxigenic Escherichia coli (ETEC) is the most common cause of children diarrhea in the world. Adhesion of ETEC to small intestine is an important virulence trait. One of the most prevalent colonization factors (CFs) in human is CFA/I fimbriae and CfaE which is the required binding factor for adhesion of ETEC to intestinal mucosa.We optimized cfaE gene codons according to codon bias of E. coli to achieve a high level of recombinant protein expression. The optimized gene was expressed in E. coli and rCFaE protein was used for mice immunization. Blocking activity of the obtained antibody was examined by microplate agglutination inhibition test. SDS-PAGE analysis indicated that the optimized sequence of cfaE produces a suitable amount of rCFaE in comparison with native gene sequence. This optimized rCFaE protein could induces strong humoral response in mice and the antibody obtained against rCFaE inhibited the adhesion of ETEC to human group A erythrocytes. It is concluded that codon optimization is a useful approach for obtaining large quantities of recombinant rCFaE protein. With regard to the results of hemagglutination inhibition test, codon optimization and increased production of recombinant protein expressed in E. coli did not affect the immunogenicity potential of CFaE.  相似文献   
29.
Aβ is the main constituent of the amyloid plaque found in the brains of patients with Alzheimer’s disease. There are two common isoforms of Aβ: the more common form, Aβ40, and the less common but more amyloidogenic form, Aβ42. Crocin is a carotenoid from the stigma of the saffron flower and it has many medicinal properties, including antioxidant effects. In this study, we examined the potential of crocin as a drug candidate against Aβ42 amyloid formation. The thioflavin T-binding assay and electron microscopy were used to examine the effects of crocin on the extension and disruption of Aβ42 amyloids. To further investigate the relationship between crocin and Aβ42 structure, we analyzed peptide conformation using the ANS-binding assay and circular dichroism (CD) spectroscopy. An increase in the thioflavin T fluorescence intensity upon incubation revealed amyloid formation in Aβ42. It was found that crocin has the ability to prevent amyloid formation by decreasing the fluorescence intensity. Electron microscopy data also indicated that crocin decreased the amyloid fibril content of Aβ. The ANS-binding assay showed that crocin decreased the hydrophobic area in incubated Aβ42. CD spectroscopy results also showed that the peptide undergoes a structural change to α-helical and β-turn. Our study shows that the anti-amyloidogenic effect of crocin may be exerted not only by the inhibition of Aβ amyloid formation but also by the disruption of amyloid aggregates. Therefore, crocin could be essential in the search for therapies inhibiting aggregation or disrupting aggregation.  相似文献   
30.
Circulating nucleic acids (CNAs) are under investigation as a liquid biopsy in cancer. However there is wide variation in blood processing and methods for isolation of circulating free DNA (cfDNA) and microRNAs (miRNAs). Here we compare the extraction efficiency and reproducibility of 4 commercially available kits for cfDNA and 3 for miRNA using spike-in of reference templates. We also compare the effects of increasing time between venepuncture and centrifugation and differential centrifugation force on recovery of CNAs. cfDNA was quantified by TaqMan qPCR and targeted deep sequencing. miRNA profiles were assessed with TaqMan low-density arrays and assays. The QIAamp® DNA Blood Mini and Circulating nucleic acid kits gave the highest recovery of cfDNA and efficient recovery (>90%) of a 564bp spike-in. Moreover, targeted sequencing revealed overlapping cfDNA profiles and variant depth, including detection of HER2 gene amplification, using the Ion AmpliSeq™Cancer Hotspot Panel v2. Highest yields of miRNA and the synthetic Arabidopsis thaliana miR-159a spike-in were obtained using the miRNeasy Serum/Plasma kit, with saturation above 200 µl of plasma. miRNA profiles showed significant variation with increasing time before centrifugation (p<0.001) and increasing centrifugation force, with depletion of platelet associated miRNAs, whereas cfDNA was unaffected. However, sample replicates showed excellent reproducibility on TaqMan low density arrays (ρ = 0.96, p<0.0001). We also successfully generated miRNA profiles for plasma samples stored > 12 years, highlighting the potential for analysis of stored sample biobanks. In the era of the liquid biopsy, standardisation of methods is required to minimise variation, particularly for miRNA.  相似文献   
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