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Circadian variation in the effect of cephalothoracic nerve mass (CTNM) extract and blood of the oxygen consumption of the isolated hepatopancreas of the scorpion, Heterometrus fulvipes, was studied. Both CTNM extract and blood from 2000 animal cause maximum increase in oxygen consumption. Another maximum increase was also noted at 0800. It is inferred that a chemical factor from the CTNM is responsible for the observed changes in oxygen consumption of hepatopancreas. 相似文献
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Rui Yin Johnathan D. Guest Ghazaleh Taherzadeh Ragul Gowthaman Ipsa Mittra Jane Quackenbush Brian G. Pierce 《PLoS computational biology》2021,17(9)
The SARS-CoV-2 pandemic highlights the need for a detailed molecular understanding of protective antibody responses. This is underscored by the emergence and spread of SARS-CoV-2 variants, including Alpha (B.1.1.7) and Delta (B.1.617.2), some of which appear to be less effectively targeted by current monoclonal antibodies and vaccines. Here we report a high resolution and comprehensive map of antibody recognition of the SARS-CoV-2 spike receptor binding domain (RBD), which is the target of most neutralizing antibodies, using computational structural analysis. With a dataset of nonredundant experimentally determined antibody-RBD structures, we classified antibodies by RBD residue binding determinants using unsupervised clustering. We also identified the energetic and conservation features of epitope residues and assessed the capacity of viral variant mutations to disrupt antibody recognition, revealing sets of antibodies predicted to effectively target recently described viral variants. This detailed structure-based reference of antibody RBD recognition signatures can inform therapeutic and vaccine design strategies. 相似文献
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In silico tools for predicting peptides binding to HLA-class II molecules: more confusion than conclusion 总被引:2,自引:0,他引:2
Identification of promiscuous peptides, which bind to human leukocyte antigen, is indispensable for global vaccination. However, the development of such vaccines is impaired due to the exhaustive polymorphism in human leukocyte antigens. The use of in silico tools for mining such peptides circumvents the expensive and laborious experimental screening methods. Nevertheless, the intrepid use of such tools warrants a rational assessment with respect to experimental findings. Here, we have adopted a 'bottom up' approach, where we have used experimental data to assess the reliability of existing in silico methods. We have used a data set of 179 peptides from diverse antigens and have validated six commonly used in silico methods; ProPred, MHC2PRED, RANKPEP, SVMHC, MHCPred, and MHC-BPS. We observe that the prediction efficiency of the programs is not balanced for all the HLA-DR alleles and there is extremely high level of discrepancy in the prediction efficiency apropos of the nature of the antigen. It has not escaped our notice that the in silico methods studied here are not very proficient in identifying promiscuous peptides. This puts a much constraint on the intrepid use of such programs for human leukocyte antigen class II binding peptides. We conclude from this study that the in silico methods cannot be wholly relied for selecting crucial peptides for development of vaccines. 相似文献
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This paper describes a database for cell signaling enzymes. Our web database offers methods to study, interpret and compare cell-signaling enzymes. Searching and retrieving data from this database has been made easy and user friendly and it is well integrated with other related databases. We believe the end user will be benefited from this database. AVAILABILITY: http://www.sastra.edu/dcse/index.html. 相似文献
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M. K. Gowthaman S. K. Rakshit K. Krishnaiah A. Baradarajan 《Bioprocess and biosystems engineering》1991,7(1-2):41-46
The performance of a tapered reactor for the continuous cultivation of bakers' yeast (SCP) from cane molasses has been compared with that of a conventional cylindrical reactor. It is found that the tapered reactor has less non-idealities (bypass and deadspace).Using the experimentally evaluated bypass and deadspace values, a model for predicting conversions of substrate (cane molasses), based on the RTD model proposed by Cholette and Cloutier has been developed. The experimental substrate conversions are found to match the model satisfactorily.List of Symbols
D h–1
dilution rate
- E()
exit age distribution function
-
K
s
kg/m3
Monod's saturation constant
- -r
sa
kg/(m3 · h)
rate of substrate utilization
-
S kg/m3
substrate concentration expressed as dextrose equivalent (DE)
-
S
a
kg/m3
substrate concentration in active zone
-
S
0 kg/m3
initial substrate concentration
-
S/S
0
dimensionless substrate concentration
-
v
a
dm3/h
volumetric flow through active zone
-
v
b
dm3/h
volumetric flow through bypass stream
-
u
l
dm3/h
substrate feed rate
-
v
g
dm3/min
air-flow rate
-
V dm3
total working volume of the reactor
-
V
a
dm3
volume of active zone in reactor
-
V
d
dm3
volume of dead zone in reactor
-
X kg/m3
biomass concentration
Greek Letters
fraction of bypass of feed, v
b
/v
l
-
fraction of deadspace, V
d
/V
-
dimensionless residence time
-
m
h–1
maximum specific growth rate
-
h
mean residence time, V/v
l
相似文献
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BCG has been administered globally for more than 75 years, yet tuberculosis (TB) continues to kill more than 2 million people annually. Further, BCG protects childhood TB but is quite inefficient in adults. This indicates that BCG fails to induce long-term protection. Hence there is a need to explore alternative vaccination strategies that can stimulate enduring T cell memory response. Dendritic cell based vaccination has attained extensive popularity following their success in various malignancies. In our previous study, we have established a novel and unique vaccination strategy against Mycobacterium tuberculosis (M. tb) and Salmonella typhimurium by utilizing infected macrophages (IM). In short-term experiments (30 days), substantial degree of protection was observed. However, remarkable difference was not observed in long-term studies (240 days) due to failure of the vaccine to generate long-lasting memory T cells. Hence, in the present study we employed T cell memory augmenting cytokines IL-1+IL-6+TNF-α and IL-7+IL-15 for the induction of the enhancement of long-term protection by the vaccine. We co-administered the M. tb infected macrophages vaccine with IL-1+IL-6+TNF-α (IM-1.6.α) and IL-7+IL-15 (IM-7.15). The mice were then rested for a reasonably large period (240 days) to study the bona fide T cell memory response before exposing them to aerosolized M. tb. IM-1.6.α but not IM-7.15 significantly improved memory T cell response against M. tb, as evidenced by recall responses of memory T cells, expansion of both central as well as effector memory CD4 and CD8 T cell pools, elicitation of mainly Th1 memory response, reduction in the mycobacterial load and alleviated lung pathology. Importantly, the protection induced by IM-1.6.α was significantly better than BCG. Thus, this study demonstrates that not only antigen-pulsed DCs can be successfully employed as vaccines against cancer and infectious diseases but also macrophages infected with M. tb can be utilized with great efficacy especially in protection against TB. 相似文献
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Jessica L. Martin Phillip A. Yates Radika Soysa Joshua F. Alfaro Feng Yang Kristin E. Burnum-Johnson Vladislav A. Petyuk Karl K. Weitz David G. Camp II Richard D. Smith Phillip A. Wilmarth Larry L. David Gowthaman Ramasamy Peter J. Myler Nicola S. Carter 《PLoS pathogens》2014,10(2)
The ability of Leishmania to survive in their insect or mammalian host is dependent upon an ability to sense and adapt to changes in the microenvironment. However, little is known about the molecular mechanisms underlying the parasite response to environmental changes, such as nutrient availability. To elucidate nutrient stress response pathways in Leishmania donovani, we have used purine starvation as the paradigm. The salvage of purines from the host milieu is obligatory for parasite replication; nevertheless, purine-starved parasites can persist in culture without supplementary purine for over three months, indicating that the response to purine starvation is robust and engenders parasite survival under conditions of extreme scarcity. To understand metabolic reprogramming during purine starvation we have employed global approaches. Whole proteome comparisons between purine-starved and purine-replete parasites over a 6–48 h span have revealed a temporal and coordinated response to purine starvation. Purine transporters and enzymes involved in acquisition at the cell surface are upregulated within a few hours of purine removal from the media, while other key purine salvage components are upregulated later in the time-course and more modestly. After 48 h, the proteome of purine-starved parasites is extensively remodeled and adaptations to purine stress appear tailored to deal with both purine deprivation and general stress. To probe the molecular mechanisms affecting proteome remodeling in response to purine starvation, comparative RNA-seq analyses, qRT-PCR, and luciferase reporter assays were performed on purine-starved versus purine-replete parasites. While the regulation of a minority of proteins tracked with changes at the mRNA level, for many regulated proteins it appears that proteome remodeling during purine stress occurs primarily via translational and/or post-translational mechanisms. 相似文献