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991.
Nine Brazilian Amaryllidaceae species were studied for their alkaloid composition and acetylcholinesterase (AChE) inhibitory activity via GC–MS and a modified Ellman assay, respectively. A total of thirty-six alkaloids were identified in these plants, of which Hippeastrum papilio and H. glaucescens exhibited the highest galanthamine content and the best IC50 values against AChE. Furthermore, Hippeastrum vittatum and Rhodophiala bifida also showed notable AChE inhibitory effects. X-ray crystallographic data for four galanthamine-type compounds revealed significant differences in the orientation of the N-methyl group, which are shown to be related to AChE inhibition.  相似文献   
992.
A series of Na15(SO4)5F4Cl phosphors doped with Ce3+ ions was prepared using the wet chemical method. X‐Ray diffraction studies were used to determine their phase formation and purity. Fourier transform infrared spectroscopy effectively identified the chemical bonds present in the molecule. The photoluminescence properties of the as‐prepared phosphors were investigated and the Ce3+ ions in these hosts were found to give broadband emission in the UV range. For the thermoluminescence study, phosphors were irradiated with a 5 Gy dose of γ‐rays from a 60Co source. Chen’s half‐width method was employed to calculate the trapping parameters from the thermoluminescence glow curve. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
993.

Background

The Government of India declared TB as a notifiable disease in 2012. There is a paucity of information on the government''s mandatory TB notification order from the perspective of private medical practitioners (PPs).

Objective

To understand the awareness, perception and barriers on TB notification among PPs in Chennai, India.

Methods

Total of 190 PPs were approached in their clinics by trained field staff who collected data using a semi-structured and pre-coded questionnaire after getting informed consent. The data collected included PPs'' specialization, TB management practices, awareness about the TB notification order, barriers in its implementation and their suggestions to improve notification.

Results

Of 190 PPs from varied specializations, 138 (73%) had diagnosed TB cases in the prior three months, of whom 78% referred these patients to government facilities. Of 138 PPs, 73% were aware of the order on mandatory TB notification, of whom 46 (33%) had ever notified a TB case. Of 120 PPs, 63% reported reasons for not notifying TB cases. The main reasons reported for not notifying were lack of time (50%), concerns regarding patients'' confidentiality (24%) and fear of offending patients (11%). Of 145 PPs, 76% provided feedback about information they felt uncomfortable reporting during notification. PPs felt most uncomfortable reporting patient''s government-issued Aadhar number (77%), followed by patient''s phone number (37%) and residential address (26%). The preferred means of notification was through mobile phone communication (24%), SMS (18%) and e-mail (17%).

Conclusion

This study highlights that one-fourth of PPs were not aware of the TB notification order and not all those who were aware were notifying. While it is important to sensitize PPs on the importance of TB notification it is also important to understand the barriers faced by PPs and to make the process user-friendly in order to increase TB notification.  相似文献   
994.
Ehrlichia chaffeensis is a tick-borne rickettsial pathogen and the causative agent of human monocytic ehrlichiosis. Transmitted by the Amblyomma americanum tick, E. chaffeensis also causes disease in several other vertebrate species including white-tailed deer and dogs. We have recently described the generation of an attenuated mutant strain of E. chaffeensis, with a mutation in the Ech_0660 gene, which is able to confer protection from secondary, intravenous-administered, wild-type E. chaffeensis infection in dogs. Here, we extend our previous results, demonstrating that vaccination with the Ech_0660 mutant protects dogs from physiologic, tick-transmitted, secondary challenge with wild-type E. chaffeensis; and describing, for the first time, the cellular and humoral immune responses induced by Ech_0660 mutant vaccination and wild-type E. chaffeensis infection in the canine host. Both vaccination and infection induced a rise in E. chaffeensis-specific antibody titers and a significant Th1 response in peripheral blood as measured by E. chaffeensis antigen-dependent CD4+ T cell proliferation and IFNγ production. Further, we describe for the first time significant IL-17 production by peripheral blood leukocytes from both Ech_0660 mutant vaccinated animals and control animals infected with wild-type E. chaffeensis, suggesting a previously unrecognized role for IL-17 and Th17 cells in the immune response to rickettsial pathogens. Our results are a critical first step towards defining the role of the immune system in vaccine-induced protection from E. chaffeensis infection in an incidental host; and confirm the potential of the attenuated mutant clone, Ech_0660, to be used as a vaccine candidate for protection against tick-transmitted E. chaffeensis infection.  相似文献   
995.
Macrophage migration inhibitory factor (MIF) is a glycosylated multi-functional protein that acts as an enzyme as well as a cytokine. MIF mediates its actions through a cell surface class II major histocompatibility chaperone, CD74 and co-receptors such as CD44, CXCR2, CXCR4 or CXCR7. MIF has been implicated in the pathogenesis of several acute and chronic inflammatory diseases. Although MIF is a molecule of biomedical importance, a public resource of MIF signaling pathway is currently lacking. In view of this, we carried out detailed data mining and documentation of the signaling events pertaining to MIF from published literature and developed an integrated reaction map of MIF signaling. This resulted in the cataloguing of 68 molecules belonging to MIF signaling pathway, which includes 24 protein-protein interactions, 44 post-translational modifications, 11 protein translocation events and 8 activation/inhibition events. In addition, 65 gene regulation events at the mRNA levels induced by MIF signaling have also been catalogued. This signaling pathway has been integrated into NetPath (http://www.netpath.org), a freely available human signaling pathway resource developed previously by our group. The MIF pathway data is freely available online in various community standard data exchange formats. We expect that data on signaling events and a detailed signaling map of MIF will provide the scientific community with an improved platform to facilitate further molecular as well as biomedical investigations on MIF.  相似文献   
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Plant Molecular Biology Reporter - Sesquiterpenoid Zerumbone, the principal secondary metabolite in Zingiber zerumbet Smith, has been identified as the putative molecule conferring resistance...  相似文献   
999.
In this article a characterisation of the Gumbel's Bivariate Exponential Distribution is established on the basis of the properties of the conditional expectation of the component variables. The characterising property is proposed as the definition of lack of memory in the bivariate case.  相似文献   
1000.
Morphogenesis and plant regeneration were analyzed in axenic tissueculture of the red alga Solieria filiformis (Kützing)Gabrielson. Thallus segments cultured in ASP 12-NTA synthetic medium showedgrowth of filaments formed by divisions of cortical, subcortical and medullarycells (filamentous explants), whereas in seawater enriched with Von Stosch'ssolution, thallus segments developed branches. Filamentous explants were abletoregenerate plants when transferred from a solid to a liquid medium. Plantregeneration was significantly promoted by treatment with plant growthregulators on filamentous explants formed from intercalary segments, up to 67plantlets per explant in treatments with 6-benzylaminopurine (5.0 mgl–1), in contrast to three plantlets in controlslackingplant growth regulators. These adventitious plantlets developed into plantsmorphologically similar to those originated from germinating spores. Theseresults indicate that plant growth regulators play a role on the regulation ofmorphogenesis, and could be useful for micropropagation of colloid-producingredalgae.  相似文献   
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