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131.
132.
Ex vivo expanded decidua-basalis(DB)-derived mesenchymal stem cells (MSCs) obtained from single donors have demonstrated therapeutic benefits in in vitro and in vivo studies. In this report, the intravenous and subcutaneous administration of DB-MSCs obtained from five healthy donors was assessed considering clinical grade proliferation, accessibility, and toxic effects in Wistar albino rats. The ability of the obtained DB-MSCs for differentiating, as well as their expression of several cell surface markers and immunomodulatory activities, were all assessed. Clinical standard proliferated cells were administered to animals intravenously and subcutaneously in a series of preclinical models in order to assess their in vivo toxicity, general safety, and tumorigenic possibilities. We established that DB cells exhibit structural and functional traits with MSCs. At various doses supplied intravenously or subcutaneously, the research showed no fatality, abnormal response to therapy, or substantial pathological modifications in the rats. Furthermore, there was no indication of prenatal damage in the same animal species when the rats were repeatedly treated with DBMSCs. Thus, DBMSCs were demonstrated to be non-toxic, non-teratogenic, and non-tumorigenic. To determine whether they can be administrated to human patients without risk, more investigation is recommended.  相似文献   
133.
The rise and expansion of Tibetan Empire in the 7th to 9th centuries AD affected the course of history across East Eurasia, but the genetic impact of Tibetans on surrounding populations remains undefined. We sequenced 60 genomes for four populations from Pakistan and Tajikistan to explore their demographic history. We showed that the genomes of Balti people from Baltistan comprised 22.6–26% Tibetan ancestry. We inferred a single admixture event and dated it to about 39–21 generations ago, a period that postdated the conquest of Baltistan by the ancient Tibetan Empire. The analyses of mitochondrial DNA, Y, and X chromosome data indicated that both ancient Tibetan males and females were involved in the male-biased dispersal. Given the fact that the Balti people adopted Tibetan language and culture in history, our study suggested the impact of Tibetan Empire on Baltistan involved dominant cultural and minor demic diffusion.  相似文献   
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Abstract

The modular structure of bacterial ribonuclease P (RNase P) ribozymes, which recognize tertiary structures of precursor tRNAs (pre-tRNAs) to cleave their 5′ leader sequence, can be dissected physically into the two structured domain RNAs (S-domain and C-domain). Separately prepared S-domain RNA and C-domain RNA assemble to form bimolecular forms of RNase P ribozymes. We analyzed the effects of polyethylene glycols (PEGs) on pre-tRNA cleavage catalyzed by bimolecular RNase P ribozymes to examine the effects of molecular crowding on the reaction. PEG molecular crowders significantly enhanced the activities of bimolecular RNase P ribozymes, some of which were hardly active without PEGs.  相似文献   
136.
Grapevine fanleaf virus (GFLV) is the major causal agent of the grapevine degeneration disease. To characterize the genomic RNA2 segment from Iranian isolates of GFLV, leaf samples were collected from infected vineyards in different locations with a long history of vine cultivation. Four isolates were selected for cloning and sequencing on the basis of the restriction profiles of RT‐PCR products. The sequencing data revealed that the RNA2 of the Iranian GFLV isolates were the shortest compared with that of all previously described GFLV isolates. The sizes were 3730 nucleotides (nt) for Shir‐Amin and Urmia isolates and 3749 nt for Takestan and Bonab isolates (excluding the poly (A) tail), due to deletion events in both 5′ and 3′ non‐coding regions. In the phylogenetic tree based on the full‐length nucleotide sequences of GFLV RNA2, all the GFLV isolates clustered into two groups with the exception of the Hungarian isolate (GHu). The Iranian isolates grouped as a distinct cluster. Recombination analyses showed that GFLV‐NW (Germany), GFLV‐F13 (reference isolate), GFLV isolate Shir‐Amin (Iran) and Arabis mosaic virus isolate Lv were recombinant isolates and one of their parents belonged to the same lineage as the Iranian isolates. These findings suggest that these isolates originated from a common ancestor.  相似文献   
137.
This research was carried out to evaluate the antidiabetic effects of zinc oxide nanoparticles (ZnO NPs) and thiamine following experimental diabetes. Fifty-six 6-week-old female mice were used and divided into seven groups of eight animals. Diabetes was induced in fasted mice by using intraperitoneal (IP) injection of alloxan (180 mg/kg). Groups included (I) non-diabetic control, (II) thiamine (30 mg/l, IP), (III) alloxan-induced diabetic mice, (IV) diabetes + ZnO NPs (0.1 mg/kg IP), (V) diabetes + ZnO NPs (0.5 mg/kg IP), (VI) diabetes + ZnO NPs (0.1 mg/kg IP) + thiamine (30 mg/l, IP), and (VII) diabetes + ZnO NPs (0.5 mg/kg IP) + thiamine (30 mg/l, IP). Coincident with pancreas recovery, in diabetic treated mice (groups IV to VII), the mean islet volume, islets per square micrometer, and volume density of the pancreas had increased than in alloxan-induced diabetic mice. ZnO NPs and thiamine induced a decreasing blood glucose, lower serum triglyceride (TG), LDL, and total cholesterol (TC) levels in alloxan-induced diabetic mice treated with ZnO NPs and thiamine, simultaneously increasing HDL as well. In conclusion, ZnO NPs and thiamine are potent antidiabetic factors, and that, these compound supplementation possesses hypoglycemic properties and have effect on serum lipid parameters in diabetes mice.  相似文献   
138.
Parkinson’s disease is the second most common neurodegenerative disease that occurs due to cellular autophagy deficiency and the accumulation of alpha-synuclein in the dopaminergic neurons of the substantia nigra pars compacta (SNc) of the brainstem. The SMER28 (also known as 6-Bromo-N-prop-2-enylquinazolin-4-amine) is an autophagy inducer. In this study, the neuroprotective effects of SMER28 were evaluated on autophagy induction, antioxidant system activation, and microgliosis attenuation. The Parkinson’s disease model was developed in the male Wistar rats by injection of 6-OHDA into the left striatum. Apomorphine-induced behavior assessment test and SNc cell counting were performed to investigate the neuroprotective effects of SMER28. This study examined the pharmacological roles of SMER28, especially by focusing on the autophagy (p62/ SQSTM1 and LC3II/LC3I ratio where LC3 is microtubule-associated protein 1A/1B-light chain 3), inhibiting free radicals, and activating the antioxidant system. The levels of malondialdehyde (MDA), reactive oxygen species (ROS), glutathione (GSH), GSH/glutathione peroxidase (GPX), superoxide dismutase (SOD) activity and nuclear factor-erythroid 2-related factor-2 (Nrf2) were measured to evaluate the antioxidant activity of SMER28. Moreover, Iba-1 (ionized calcium binding adaptor molecule, indicating microgliosis) and tyrosine hydroxylase immunoreactivities were evaluated in the SNc. In the behavioral assessment, SMER28 (50 µg/kg) attenuated damages to the SNc dopaminergic neurons, characterized by improved motor function. The tissue observations revealed that SMER28 prevented the destruction of SNc neurons and attenuated microgliosis as well. It also reduced MDA and ROS production and increased GSH, GPX, SOD, and Nrf2 activities by inducing autophagy (decreasing p62 and increasing LC3II/LC3I ratio). Consequently, possibly with further studies, it can be considered as a drug for neurodegenerative diseases with proteinopathy etiology.  相似文献   
139.
Japanese encephalitis (JE), a viral disease has seen a drastic and fatal enlargement in the northern states of India in the current decade. The better and exact cure for the disease is still in waiting. For the cause an in silico strategy in the development of the peptide vaccine has been taken here for the study. A computational approach to find out the Major Histocompatibility Complex (MHC) binding peptide has been implemented. The prediction analysis identified MHC class I (using propred I) and MHC class II (using propred) binding peptides at an expectable percent predicted IC (50) threshold values. These predicted Human leukocyte antigen [HLA] allele binding peptides were further analyzed for potential conserved region using an Immune Epitope Database and Analysis Resource (IEDB). This analysis shows that HLA-DRB1*0101, HLA-DRB3*0101, HLA-DRB1*0401, HLA-DRB1*0102 and HLA-DRB1*07:01% of class II (in genotype 2) and HLA-A*0101, HLA-A*02, HLA-A*0301, HLA-A*2402, HLA-B*0702 and HLA-B*4402% of HLA I (in genotype 3) bound peptides are conserved. The predicted peptides MHC class I are ILDSNGDIIGLY, FVMDEAHFTDPA, KTRKILPQIIK, RLMSPNRVPNYNLF, APTRVVAAEMAEAL, YENVFHTLW and MHC class II molecule are TTGVYRIMARGILGT, NYNLFVMDEAHFTDP, AAAIFMTATPPGTTD, GDTTTGVYRIMARGI and FGEVGAVSL found to be top ranking with potential super antigenic property by binding to all HLA. Out of these the predicted peptide FVMDEAHFTDPA for allele HLA-A*02:01 in MHC class I and NYNLFVMDEAHFTDP for allele HLA-DRB3*01:01 in MHC class II was observed to be most potent and can be further proposed as a significant vaccine in the process. The reported results revealed that the immune-informatics techniques implemented in the development of small size peptide is useful in the development of vaccines against the Japanese encephalitis virus (JEV).  相似文献   
140.
Polyamines are a promising class of molecules that can modulate RNA enzyme activities. To analyze the effects of the number of amine moieties systematically, we employed four polyamines sharing dimethylene units to connect amine moieties. As a model RNA enzyme, we used a structurally unstable group I ribozyme, which was activated most and least efficiently by tetraethylenepentamine and diethylenetriamine respectively.  相似文献   
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