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31.
The genus Phlebovirus of the family Bunyaviridae consists of approximately 70 named viruses, currently assigned to nine serocomplexes (species) based on antigenic similarities. Sixteen other named viruses that show little serologic relationship to the nine recognized groups are also classified as tentative species in the genus. In an effort to develop a more precise classification system for phleboviruses, we are attempting to sequence most of the named viruses in the genus with the goal of clarifying their phylogenetic relationships. In this report, we describe the serologic and phylogenetic relationships of 13 viruses that were found to be members of the Candiru serocomplex; 6 of them cause disease in humans. Analysis of full genome sequences revealed branching inconsistencies that suggest five reassortment events, all involving the M segment, and thus appear to be natural reassortants. This high rate of reassortment illustrates the inaccuracy of a classification system based solely on antigenic relationships.  相似文献   
32.
Arsenic (As) toxicity and its biochemical effects have been mostly evaluated in ferns and a few higher plants. In this study, we investigated the effect of As (10.0 and 50.0 μM) on seedling growth, root anatomy, lipid peroxidation (malondialdehyde and conjugated dienes), electrolyte leakage, H2O2 content, root oxidizability and the activities of antioxidant enzymes in mung bean (Phaseolus aureus Roxb.). Arsenic significantly enhanced lipid peroxidation (by 52% at 50.0 μM As), electrolyte leakage and oxidizability in roots. However, there was no significant change in H2O2 content. Arsenic toxicity was associated with an increase in the activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX) and glutathione reductase (GR). In response to 50.0 μM As, the activities of SOD and GR increased by over 60% and 90%, respectively. At 10.0 μM As, the activity of ascorbate peroxidase (APX) increased by 83%, whereas at 50.0 μM it declined significantly. The catalase (CAT) activity, on the other hand, decreased in response to As exposure, and it corresponded to the observed decrease in H2O2 content. We conclude that As causes a reduction in root elongation by inducing an oxidative stress that is related to enhanced lipid peroxidation, but not to H2O2 accumulation.  相似文献   
33.

Background

Neo-vascularization, an indispensible phenomenon for tissue regeneration, facilitates repair and remodeling of wound tissues. This process is impaired in chronic wounds due to reduced number and recruitment of endothelial cells (ECs), thereby necessitating development of newer strategies to enhance the EC repertoire as a therapeutic approach.

Methods

We explored the ‘plasticity’ of Wharton's jelly derived–mesenchymal stromal cells (WJ-MSCs) using an anti-inflammatory drug-mediated enhanced trans-differentiation into ECs, based on our observation of temporal decrease in COX-2 expression during trans-differentiation of MSCs into ECs at day 7 and 14 along with mature ECs.

Results

At a physiological level, an increased DiI-labeled acetylated-low density lipoprotein (DiI-Ac-LDL) uptake, proliferation, migration and chick chorio allantoic membrane (CAM)-vasculogenesis occurred while at a molecular level significant up-regulation in messenger RNA (mRNA) and protein expression of endothelial-specific markers, Vegfr2, Pecam, eNOS, VE-Cadh and Tie-2, along with an activated p-VEGFR2 and its downstream mediators were observed in celecoxib-preconditioned ECs as compared with WJ-MSCs. Green fluorescent protein (GFP)-expressing stable WJ-MSCs and trans-differentiated EC-D14 in the absence/presence of celecoxib were generated using antibiotic selection for intradermal transplantation at the wound site on a murine ‘excisional splinting wound’ model. Engraftment of transplanted human cells in immunosuppressant-treated mice was confirmed by a significant increase in the expression levels of human gene-specific endothelial markers at the regenerated wound sites. Morphometrically, increased vascularity and percent wound closure were observed in regenerated wounds of mice transplanted with celecoxib-preconditioned-EC-D14.

Conclusion

Cox-2 inhibition led to an enhanced trans-differentiation of WJ-MSCs into ECs that, when transplanted, accelerated the skin regeneration by engraftment and neo-vascularization at the wound bed, suggesting a plausible new therapeutic role of celecoxib.  相似文献   
34.
35.
Among putative downstream synaptic targets of β-amyloid (Aβ) are signaling molecules involved in synaptic function, memory formation and cognition, such as the MAP kinases, MKPs, CaMKII, CREB, Fyn, and Tau. Here, we assessed the activation and interaction of signaling pathways upon prolonged exposure to Aβ in model nerve cells expressing nicotinic acetylcholine receptors (nAChRs). Our goal was to characterize the steps underlying sensitization of the nerve cells to neurotoxicity when Aβ-target receptors are present. Of particular focus was the connection of the activated signaling molecules to oxidative stress. Differentiated neuroblastoma cells expressing mouse α4β2-nAChRs were exposed to Aβ1–42 for intervals from 30 min to 3 days. The cells and cell-derived protein extracts were then probed for activation of signaling pathway molecules (ERK, JNK, CaMKII, CREB, MARCKS, Fyn, tau). Our results show substantial, progressive activation of ERK in response to nanomolar Aβ exposure, starting at the earliest time point. Increased ERK activation was followed by JNK activation as well as an increased expression of PHF-tau, paralleled by increased levels of reactive oxygen species (ROS). The impact of prolonged Aβ on the levels of pERK, pJNK, and ROS was attenuated by MEK-selective and JNK-selective inhibitors. In addition, the MEK inhibitor as well as a JNK inhibitor attenuated Aβ-induced nuclear fragmentation, which followed the changes in ROS levels. These results demonstrate that the presence of nAChRs sensitizes neurons to the neurotoxic action of Aβ through the timed activation of discrete intracellular signaling molecules, suggesting pathways involved in the early stages of Alzheimer disease.  相似文献   
36.

Background

Current study has been designed to evaluate the chemical composition of essential and fixed oils from stem and leaves of Perovskia abrotanoides and antioxidant and antimicrobial activities of these oils.

Results

GC-MS analysis of essential oil identified 19 compounds with (E)-9-dodecenal being the major component in stem and hexadecanoic acid in leaves. In contrast, GC-MS analysis of fixed oil showed 40 constituents with α-amyrin the major component in stem and α-copaene in leaves. The antioxidant activity showed the highest value of 76.7% in essential oil from leaves in comparison with fixed oil from stem (45.9%) through inhibition of peroxidation in linoleic acid system. The antimicrobial assay tested on different microorganisms (e.g. E. coli, S. aureus, B. cereus, Nitrospira, S. epidermis, A. niger, A. flavus and C. albicans) showed the higher inhibition zone at essential oil from leaves (15.2 mm on B. cereus) as compared to fixed oil from stem (8.34 mm on S. aureus) and leaves (11.2 mm on S. aureus).

Conclusions

The present study revealed the fact that essential oil analyzed from Perovskia abrotanoides stem and leaves could be a promising source of natural products with potential antioxidant and antimicrobial activities, as compared to fixed oil.  相似文献   
37.
Japanese encephalitis (JE), a viral disease has significantly increased worldwide especially, in the developing region due to challenges in immunization, vector control and lack of appropriate treatment methods. An effective, yet an expensive heat-killed vaccine is available for the disease. Therefore, the design and development of short peptide vaccine candidate is promising. We used immune-informatics methods to perform a comprehensive analysis of the entire JEV proteome of north Indian isolate to identify the conserved peptides binding known specific HLA alleles among the documented JEV genotypes 1, 2, 3, 4 and 5. The prediction analysis identified 102 class I (using propred I) and 118 class II (using propred) binding peptides at 4% threshold value. These predicted HLA allele binding peptides were further analyzed for potential conserved region using IEDB (an immune epitope database and analysis resource). This analysis shows that 78.81% of class II (in genotype 2) and 76.47% of HLA I (in genotype 3) bound peptides are conserved. The peptides IPIVSVASL, KGAQRLAAL, LAVFLICVL and FRTLFGGMS, VFLICVLTV, are top ranking with potential super antigenic property by binding to all HLA allele members of B7 and DR4 super-types, respectively. This data finds application in the design and development of short peptide vaccine candidates and diagnostic agents for JE following adequate validation and verification.  相似文献   
38.

Objective

Our primary objective was to evaluate the effect of peer counselling by mother support groups (MSG''s) in improving the infant and young child feeding (IYCF) practices in the community.

Methods

We conducted this repeated-measure before and after study in the Lalitpur district of Uttar Pradesh, India between 2006 and 2011. We assessed the IYCF practices before and after creating MSG''s within the community. The feeding practices were reassessed at two time points–2 (T1) and 5 years (T2) after the intervention and compared with that of the pre-intervention phase (T0).

Results

The total population covered by the project from the time of its initiation was 105000. A total of 425 (T0), 480 (T1) and 521 (T2) mother infant pairs were selected from this population. There was significant improvement in the following IYCF practices in the community (represented as %; adjOR (95% CI, p) such as initiation of breast feeding within 1 hour at both T1 (71% vs. 11%); 19.6 (13.6, 28.2, p = <0.0001)and T2 (62% vs. 11%); 13.3 (9.4, 18.9, p = <0.0001); use of prelacteal feeds at both T1 (67% vs. 15%); 12.6 (CI: 9.0, 17.6, p<0.0001) and T2 (67% vs. 5%); 44.4 (28.8, 68.4, p = <0.0001); rates of exclusive breast feeding for 6 months at both T1 (50% vs. 7%); 13.6 (7.6, 25.0, p = <0.0001) and T2 (60% vs. 7%); 20.5 (11.3, 37.2, p = <0.0001); initiation of complementary feeding at T1 (85% vs. 54%); 5.6 (3.6, 8.7, p = <0.0001) and T2 (96% vs. 54%); 22.9 (11.8, 44.1, p = <0.0001) and complementary feeding along with continued breast feeding at both T1 (36% vs. 4.5%); 6 (1.15, 31.4, p = 0.033) and T2 (42% vs. 4.5%); 8.06 (1.96, 49.1, p = 0.005) as compared to pre-intervention period (T0) after adjusting for important social and demographic variables.

Conclusions

Peer counseling by MSG''s improved the IYCF practices in the district and could be sustained.  相似文献   
39.
As part of our drug discovery program for anti-filarial agents from Indian medicinal plants, leaves of Eucalyptus tereticornis were chemically investigated, which resulted in the isolation and characterization of an anti-filarial agent, ursolic acid (UA) as a major constituent. Antifilarial activity of UA against the human lymphatic filarial parasite Brugia malayi using in vitro and in vivo assays, and in silico docking search on glutathione-s-transferase (GST) parasitic enzyme were carried out. The UA was lethal to microfilariae (mf; LC100: 50; IC50: 8.84 µM) and female adult worms (LC100: 100; IC50: 35.36 µM) as observed by motility assay; it exerted 86% inhibition in MTT reduction potential of the adult parasites. The selectivity index (SI) of UA for the parasites was found safe. This was supported by the molecular docking studies, which showed adequate docking (LibDock) scores for UA (−8.6) with respect to the standard antifilarial drugs, ivermectin (IVM −8.4) and diethylcarbamazine (DEC-C −4.6) on glutathione-s-transferase enzyme. Further, in silico pharmacokinetic and drug-likeness studies showed that UA possesses drug-like properties. Furthermore, UA was evaluated in vivo in B. malayi-M. coucha model (natural infection), which showed 54% macrofilaricidal activity, 56% female worm sterility and almost unchanged microfilaraemia maintained throughout observation period with no adverse effect on the host. Thus, in conclusion in vitro, in silico and in vivo results indicate that UA is a promising, inexpensive, widely available natural lead, which can be designed and developed into a macrofilaricidal drug. To the best of our knowledge this is the first ever report on the anti-filarial potential of UA from E. tereticornis, which is in full agreement with the Thomson Reuter''s ‘Metadrug’ tool screening predictions.  相似文献   
40.
Cancer drug development generally performs in vivo evaluation of treatment effects that have traditionally relied on detection of morphologic changes. The emergence of new targeted therapies, which may not result in gross morphologic changes, has spurred investigation into more specific imaging methods to quantify response, such as targeted fluorescent probes and bioluminescent cells. The present study investigated tissue response to docetaxel or zoledronic acid (ZA) in a mouse model of bony metastasis. Intratibial implantations of breast cancer cells (MDA-MB-231) were monitored throughout this study using several modalities: molecular resonance imaging (MRI) tumor volume and apparent diffusion coefficient (ADC), micro-computed tomography (µCT) bone volume, bioluminescence imaging (BLI) reporting cancer cell apoptosis, and fluorescence using Osteosense 800 and CatK 680-FAST. Docetaxel treatment resulted in tumor cell kill reflected by ADC and BLI increases and tumor volume reduction, with delayed bone recovery seen in µCT prefaced by increased osteoblastic activity (Osteosense 800). In contrast, the ZA treatment group produced similar values in MRI, BLI, and Osteosense 800 fluorescence imaging readouts when compared to controls. However, µCT bone volume increased significantly by the first week post-treatment and the CatK 680-FAST signal was slightly diminished by 4 weeks following ZA treatment. Multimodality imaging provides a more comprehensive tool for new drug evaluation and efficacy screening through identification of morphology as well as function and apoptotic signaling.  相似文献   
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