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11.

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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12.
Probiotics and Antimicrobial Proteins - In this study, a bacterial strain COFCAU_P1, isolated from the digestive tract of a freshwater teleost rohu (Labeo rohita), was identified as Bacillus...  相似文献   
13.
R.R. Janghel  Y.K. Rathore 《IRBM》2021,42(4):258-267
ObjectivesAlzheimer's Disease (AD) is the most general type of dementia. In all leading countries, it is one of the primary reasons of death in senior citizens. Currently, it is diagnosed by calculating the MSME score and by the manual study of MRI Scan. Also, different machine learning methods are utilized for automatic diagnosis but existing has some limitations in terms of accuracy. So, main objective of this paper to include a preprocessing method before CNN model to increase the accuracy of classification.Materials and methodIn this paper, we present a deep learning-based approach for detection of Alzheimer's Disease from ADNI database of Alzheimer's disease patients, the dataset contains fMRI and PET images of Alzheimer's patients along with normal person's image. We have applied 3D to 2D conversion and resizing of images before applying VGG-16 architecture of Convolution neural network for feature extraction. Finally, for classification SVM, Linear Discriminate, K means clustering, and Decision tree classifiers are used.ResultsThe experimental result shows that the average accuracy of 99.95% is achieved for the classification of the fMRI dataset, while the average accuracy of 73.46% is achieved with the PET dataset. On comparing results on the basis of accuracy, specificity, sensitivity and on some other parameters we found that these results are better than existing methods.Conclusionsthis paper, suggested a unique way to increase the performance of CNN models by applying some preprocessing on image dataset before sending to CNN architecture for feature extraction. We applied this method on ADNI database and on comparing the accuracies with other similar approaches it shows better results.  相似文献   
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15.
Cottonseed remains a low‐value by‐product of lint production mainly due to the presence of toxic gossypol that makes it unfit for monogastrics. Ultra‐low gossypol cottonseed (ULGCS) lines were developed using RNAi knockdown of δ‐cadinene synthase gene(s) in Gossypium hirsutum. The purpose of the current study was to assess the stability and specificity of the ULGCS trait and evaluate the agronomic performance of the transgenic lines. Trials conducted over a period of 3 years show that the ULGCS trait was stable under field conditions and the foliage/floral organs of transgenic lines contained wild‐type levels of gossypol and related terpenoids. Although it was a relatively small‐scale study, we did not observe any negative effects on either the yield or quality of the fibre and seed in the transgenic lines compared with the nontransgenic parental plants. Compositional analysis was performed on the seeds obtained from plants grown in the field during 2009. As expected, the major difference between the ULGCS and wild‐type cottonseeds was in terms of their gossypol levels. With the exception of oil content, the composition of ULGCS was similar to that of nontransgenic cottonseeds. Interestingly, the ULGCS had significantly higher (4%–8%) oil content compared with the seeds from the nontransgenic parent. Field trial results confirmed the stability and specificity of the ULGCS trait suggesting that this RNAi‐based product has the potential to be commercially viable. Thus, it may be possible to enhance and expand the nutritional utility of the annual cottonseed output to fulfil the ever‐increasing needs of humanity.  相似文献   
16.
HapR has been given the status of a high cell density master regulatory protein in Vibrio cholerae. Though many facts are known regarding its structural and functional aspects, much still can be learnt from natural variants of the wild type protein. This work aims at investigating the nature of functional inertness of a HapR natural variant harboring a substitution of a conserved glutamate residue at position 117 which participates in forming a salt bridge by lysine (HapRV2G-E117K). Experimental evidence presented here reveals the inability of this variant to interact with various cognate promoters by in vitro gel shift assay. Furthermore, the elution profiles of HapRV2G-E117K protein along with the wild type functional HapRV2G in size-exclusion chromatography as well as circular dichroism spectra did not reflect any significant differences in its structure, thereby indicating the intactness of dimer in the variant protein. To gain further insight into the global shape of the proteins, small angle X-ray scattering analysis (SAXS) was performed. Intriguingly, increased radius of gyration of HapRV2G-E117K of 27.5 Å in comparison to the wild type protein from SAXS data analyses implied a significant alteration in the global shape of the dimeric HapRV2G-E117K protein. Structure reconstruction brought forth that the DNA binding domains were substantially “parted away” in this variant. Taken together, our data illustrates that substitution of the conserved glutamate residue by lysine in the dimerization domain induces separation of the two DNA binding domains from their native-like positioning without altering the dimeric status of HapR variant.  相似文献   
17.

Alzheimer’s disease pathogenesis is measured by two key hallmarks viz extracellular senile plaques composed of insoluble amyloid beta (Aβ) and neurofibrillary tangles composed of hyperphosphorylated tau, resulting in microtubule destabilization, synaptic damage and neurodegeneration. Accumulation of Aβ is an introducing pathological incident in Alzheimer’s disease; hence, the effect of dimethyl fumarate (DMF) on Aβ1-42-induced alterations in phosphorylated tau, related protein kinases, fibrillogenesis and microtubule assembly in neuroblastoma SH-SY5Y cells was determined. DMF attenuated Aβ1-42-induced neuronal apoptosis by down-regulating protein levels of Bcl-2/Bax, cleaved caspase-3 and caspase-9. Aβ1-42-induced upsurge in tau phosphorylation at Ser396 and Thr231 epitopes was found to be declined by DMF pretreatment. The upregulated activity of glycogen synthase kinase-3 beta (GSK-3β) by Aβ1?42 treatment was blocked by DMF pretreatment. PI3K substrate Akt (at Ser473) as well as Wnt dependent β-catenin and cyclin D1 activity was found to be upregulated by DMF pretreatment in Aβ1-42 treated cells. ThT fluorescence and MTT assay showed that DMF reduces Aβ fibrillogenesis and inhibit related cytotoxicity. Also, DMF exerts a protective effect on Aβ1-42-induced microtubule disassembly caused due to a reduction in polymerized β3-and α-tubulin. These results indicate that down-regulation of GSK-3β activity and subsequent activation of PI3K/Akt and Wnt/β-catenin signaling pathways are closely involved in the shielding effect of DMF against Aβ1-42-induced tau hyperphosphorylation. Modulating cellular events related to Aβ1-42-induced tau hyperphosphorylation, aggregation and microtubule stabilization offers new molecular insights into the defensive outcome of DMF towards appropriate management for Alzheimer’s disease.

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18.
The post-flowering stalk rots (PFSR) are a complex disease, which are widely distributed in almost all the maize growing regions across the globe. A number of fungi are involved in causing decay of the pith resulting in pre-mature wilting of the plants. Most of the commercially grown cultivars have shown a high level of disease incidence at the grain filling stage. A systematic breeding programme on PFSR was initiated in India in collaboration with Asian Regional Maize Program of CIMMYT. Under this programme, germplasm screening was carried out at four ‘hot spot’ locations in India for different diseases: Hyderabad (Cephalosporium maydis), Udaipur (Fusarium moniliforme), Ludhiana and Delhi (Macrophomina phaseolina). Across the locations, promising maize genotypes were artificially inoculated using the toothpick method, year after year; resistant plants were selfed to derive resistant inbreds. After extensive screening, three resistant lines, namely PFSR-13-5, JCY2-2-4-1-1-1-1 and JCY3-7-1-2-1-b-1, were identified. In addition, the resistance level of five pools/populations; (PFSR (Y)-C1, PFSR (white), Extra-early (White), P-100, P-300 and P-345) was upgraded to an acceptable level. These genotypes may prove useful for utilisation in breeding cultivars for resistance to PFSR.  相似文献   
19.
A cell line, CTE, derived from catla (Catla catla) thymus has been established by explant method and subcultured for more than 70 passages over a period of 400 days. The cell line has been maintained in L-15 (Leibovitz) medium supplemented with 10% fetal bovine serum. CTE cell line consists of homogeneous population of epithelial-like cells and grows optimally at 28 °C. Karyotype analysis revealed that the modal chromosome number of CTE cells was 50. Partial amplification, sequencing and alignment of fragments of two mitochondrial genes 16S rRNA and COI confirmed that CTE cell line originated from catla. Significant green fluorescent signals were observed when the cell line was transfected with phrGFP II-N mammalian expression vector, indicating its potential utility for transgenic and genetic manipulation studies. The CTE cells showed strong positivity for cytokeratin, indicating that cell line was epithelial in nature. The flow cytometric analysis of cell line revealed a higher number of cells in S-phase at 48 h, suggesting a high growth rate. The extracellular products of Vibrio cholerae MTCC 3904 were toxic to the CTE cells. This cell line was not susceptible to fish betanodavirus, the causative agent of viral nervous necrosis in a large variety of marine fish.  相似文献   
20.
We developed a micropropagation protocol for Cleome gynandra, a C4 model plant with medicinal importance. Surface-sterilized nodal segments obtained from 1 to 2-month-old field grown plant were used as explants for culture establishment and plant regeneration. Multiple shoots differentiated through bud breaking on Murashige and Skoog (MS) medium with different concentrations of benzyladenine (BA) and kinetin (Kin). The optimum shoot differentiation occurred on medium with 1.5 mg l?1 BA. Out of various concentrations and combinations of cytokinins and auxins, MS medium containing 0.5 mg l?1 BA and 0.1 mg l?1 IAA (indole-3-acetic acid) was found best for shoot multiplication. However, the differentiated shoots exhibited hyperhydration, leaf curling and early leaf fall during subculturing. To overcome these problems, regenerated shoots were transferred to the modified MS medium with reduced nitrates (825 mg l?1 NH4NO3 and 950 mg l?1 KNO3) and 100 mg l?1 (NH4)2SO4. The micropropagated shoots were rooted (i) in vitro on one-fourth strength of MS salts with 0.25 mg l?1 each of IBA (indole-3 butyric acid) and NOA (2-naphthoxyacetic acid) + 100 mg l?1 activated charcoal, and (ii) ex vitro, by treating the shoot base(s) with 200 mg l?1 of IBA for 3 min and transferred to soilrite moistened with one-fourth strength of MS macro salts in culture bottles. The plants were hardened in the greenhouse with 85 % survival rate. Micromorphological studies of the plants were conducted during hardening with reference to development and changes in vein spacing, glandular trichome and stomata. In comparison to leaves under in vitro condition, higher density of veins and glandular trichomes was observed in the leaves of hardened plants. In addition, stomata became functional during hardening which were non-functional under in vitro condition.  相似文献   
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