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91.
Clinical decision is often difficult with chlorhexidine mouthwash. The use of antioxidant mouthwashes for the treatment of periodontal disease is in practise. Therefore, it is of interest to collect gleaned information on Antioxidant mouthwashes as periodontal therapy from known literature. Improvement in treatment using antioxidant mouthwashes is reported in several studies. The mouthwash with antioxidants has similar anti-gingivitis, antiplaque and antimicrobial effects as that of chlorhexidine mouthwash. 相似文献
92.
Synthesis of Highly Immunogenic Multiple Antigenic Peptides for Epitopes of Viral Antigen to Use in ELISA 总被引:1,自引:0,他引:1
Paramasivam Saravanan Sameer Shrivastava Satish Kumar 《International journal of peptide research and therapeutics》2009,15(4):313-321
Synthesis of multiple antigenic peptides (MAPs) for predicted antigenic determinants of a viral antigen is described. The
method includes prediction of linear epitopes using predictive computer algorithms, synthesis of peptides for the predicted
regions, testing of peptides to find the most reactive sites, synthesis of MAPs and their testing. The procedure involves
manual synthesis of MAPs by solid phase peptide synthesis with Wang resin as solid support. The MAPs were prepared in eight
copies and used for immunization of rabbits to generate anti-peptide antibodies. Further, the reactivity of MAPs in detecting
the native cognate antigen in the whole virus was confirmed by ELISA. The MAP and anti-peptide antibodies could serve as diagnostic
tools for viral diseases. MAPs have efficiently been used to confirm the presence of linear antigenic and immunogenic epitopes
on viral proteins, for possible use in diagnostic and vaccine. It was suggested that this method could help in epitope mapping
of dreadful human or animal pathogens as it involves production of safe, chemically defined and non-infectious materials for
use as antigen as well as immunogen. 相似文献
93.
Singh Awtar Bali Aradhana Kumar Ashwani Yadav Rajender Kumar Minhas Paramjit Singh 《Journal of Plant Growth Regulation》2022,41(5):1989-1998
Journal of Plant Growth Regulation - Exogenous applications of plant growth regulators (PGRs) were evaluated for their effects on growth, physiological attributes, and yield of sodicity stressed... 相似文献
94.
Manoj Bhosale Anujith Kumar Mrinmoy Das Chetana Bhaskarla Vikas Agarwal Dipankar Nandi 《Microbiological research》2013,168(1):56-64
Peptidase N (PepN), the sole M1 family member in Escherichia coli, displays broad substrate specificity and modulates stress responses: it lowers resistance to sodium salicylate (NaSal)-induced stress but is required during nutritional downshift and high temperature (NDHT) stress. The expression of PepN does not significantly change during different growth phases in LB or NaSal-induced stress; however, PepN amounts are lower during NDHT stress. To gain mechanistic insights on the roles of catalytic activity of PepN in modulating these two stress responses, alanine mutants of PepN replacing E264 (GAMEN motif) and E298 (HEXXH motif) were generated. There are no major structural changes between purified wild type (WT) and mutant proteins, which are catalytically inactive. Importantly, growth profiles of ΔpepN upon expression of WT or mutant proteins demonstrated the importance of catalytic activity during NDHT but not NaSal-induced stress. Further fluorescamine reactivity studies demonstrated that the catalytic activity of PepN is required to generate higher intracellular amounts of free N-terminal amino acids; consequently, the lower growth of ΔpepN during NDHT stress increases with high amounts of casamino acids. Together, this study sheds insights on the expression and functional roles of the catalytic activity of PepN during adaptation to NDHT stress. 相似文献
95.
96.
Madhvi Kamalvanshi Anil Kumar Anuradha Jha Shiv Kumar Dhyani 《Indian journal of microbiology》2012,52(3):492-494
A study was conducted to identify common arbuscular mycorrhizal (AM) fungi present in rhizosphere of Jatropha curcas L., an important bio-diesel crop, from different arid and semi arid regions of India viz., Jodhpur (Rajasthan), Hissar (Haryana), Jhansi and Lalitpur (Uttar Pradesh) and Hyderabad (Andhra Pradesh). A total of 20 AM species were recorded, which consisted of two species of Acaulospora and 18 species of Glomus. The highest frequency of occurrence was recorded for Glomus intraradix (100%), followed by Acaulospora scrobiculata (83%), G. etunicatum (50%) and Glomus 1 (50%). Maximum species richness was recorded at Jodhpur, followed by Jhansi, Hissar, Hyderabad and Lalitpur. The results seem to suggest that species richness was more in arid regions as compared to semi arid areas. 相似文献
97.
Pramod Kumar Yadav Peter Xie Ruma Banerjee 《The Journal of biological chemistry》2012,287(45):37611-37620
Human cystathionine β-synthase (CBS) is a unique pyridoxal 5′-phosphate (PLP)-dependent enzyme that has a regulatory heme cofactor. Previous studies have demonstrated the importance of Arg-266, a residue at the heme pocket end of α-helix 8, for communication between the heme and PLP sites. In this study, we have examined the role of the conserved Thr-257 and Thr-260 residues, located at the other end of α-helix 8 on the heme electronic environment and on activity. The mutations at the two positions destabilize PLP binding, leading to lower PLP content and ∼2- to ∼500-fold lower activity compared with the wild-type enzyme. Activity is unresponsive to PLP supplementation, consistent with the pyridoxine-nonresponsive phenotype of the T257M mutation in a homocystinuric patient. The H2S-producing activities, also impacted by the mutations, show a different pattern of inhibition compared with the canonical transsulfuration reaction. Interestingly, the mutants exhibit contrasting sensitivities to the allosteric effector, S-adenosylmethionine (AdoMet); whereas T257M and T257I are inhibited, the other mutants are hyperactivated by AdoMet. All mutants showed an increased propensity of the ferrous heme to form an inactive species with a 424 nm Soret peak and exhibited significantly reduced enzyme activity in the ferrous and ferrous-CO states. Our results provide the first evidence for bidirectional transmission of information between the cofactor binding sites, suggest the additional involvement of this region in allosteric communication with the regulatory AdoMet-binding domain, and reveal the potential for independent modulation of the canonical transsulfuration versus H2S-generating reactions catalyzed by CBS. 相似文献
98.
Haimanti Biswas Subhadra Devi Gadi V. Venkata Ramana M. Durga Bharathi R. Kesava Priyan D. Taruni Manjari M. Dileep Kumar 《Biodiversity and Conservation》2012,21(5):1309-1326
The role of microzooplankton (MZP) in the pelagic trophodynamics is highly significant, but the responses of marine MZP to increasing CO2 levels are rather poorly understood. Hence the present study was undertaken to understand the responses of marine plankton to increasing CO2 concentrations. Natural water samples from the coastal Bay of Bengal were incubated under the ambient condition and high CO2 levels (703–711 μatm) for 5 days in May and June 2010. A significant negative correlation was obtained between phytoplankton and MZP abundance which indicated that phytoplankton community structure can considerably be controlled by MZP in this region. The average relative abundances of tintinnids under elevated CO2 levels were found to be significantly higher (68.65 ± 5.63% in May; 85.46 ± 9.56% in June) than observed in the ambient condition (35.68 ± 6.83% in May; 79 ± 5.36% in June). The observed dominance of small chain forming diatom species probably played a crucial role as they can be potentially grazed by tintinnids. This fact was strengthened by the observed high negative correlations between the relative abundance of major phytoplankton and tintinnids. Moreover, particulate organic carbon and total bacterial counts were also enhanced under elevated CO2 level and can serve as additional food source for ciliates. The observed responses of tintinnids to increasing CO2 might have multiple impacts on the energy transfer, nutrient and carbon cycling in the coastal water. The duration of the present study was relatively short and therefore further investigation on longer time scale needs to be done and might give us a better insight about phytoplankton and MZP species succession under elevated CO2 level. 相似文献
99.
Manon Grube Sukhbinder Kumar Freya E. Cooper Stuart Turton Timothy D. Griffiths 《Proceedings. Biological sciences / The Royal Society》2012,279(1746):4496-4504
This work tests the relationship between auditory and phonological skill in a non-selected cohort of 238 school students (age 11) with the specific hypothesis that sound-sequence analysis would be more relevant to phonological skill than the analysis of basic, single sounds. Auditory processing was assessed across the domains of pitch, time and timbre; a combination of six standard tests of literacy and language ability was used to assess phonological skill. A significant correlation between general auditory and phonological skill was demonstrated, plus a significant, specific correlation between measures of phonological skill and the auditory analysis of short sequences in pitch and time. The data support a limited but significant link between auditory and phonological ability with a specific role for sound-sequence analysis, and provide a possible new focus for auditory training strategies to aid language development in early adolescence. 相似文献
100.