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941.
Evidence for photosynthetic independence of viral multiplication in cyanophage LPP-1 infected cyanobacterium Phormidium uncinatum 总被引:1,自引:0,他引:1
P.S. Bisen Surabhi Audholia H.D. Shukla Amit Gupta D.P. Singh 《FEMS microbiology letters》1988,52(3):225-228
Abstract Pigment decomposition, oxygen evolution and CO2 fixation were measured in the cyanobacterium Phormidium uncinatum after infection with cyanophage LPP-1, under light and dark conditions. A gradual decrease in para benzoquinone supported O2 evolution, chlorophyll a and phycocyanin level were noticed after 6 h of infection. These results demonstrated decreased photosynthetic activity of the host P. uncinatum prior to the start of LPP-1 multiplication. Metabolic inhibitor investigations confirmed that the cyanophage LPP-1 multiplication was independent of host photosynthesis. 相似文献
942.
The effect of a 2-week clofibrate (0.5%)-fortified diet on peroxisomal palmitoyl-CoA and lignoceroyl-CoA ligases was studied. The activities of palmitoyl-CoA and lignoceroyl-CoA ligases in peroxisomes isolated from clofibrate-treated animals were 4.4- and 4.0-fold higher than those of the controls. The different degrees of increases in these two enzyme activities support the previous conclusions that in peroxisomes palmitoyl-CoA ligase and lignoceroyl-CoA ligase are different enzymes. Since clofibrate treatment increases both of these peroxisomal acyl-CoA ligase activities and normal palmitoyl-CoA ligase is the source of the partial activity for the oxidation of lignoceric acid in X-ALD, treatment with a hypolipidemic drug, which can increase human peroxisomal enzyme activities, may be helpful in lowering the amount of the pathogen, VLC fatty acids, in X-ALD. 相似文献
943.
Saurabh Kumar Agnihotri Balawant Kumar Ankita Jain Anjali Anjali Mahendra Pal Singh Negi Rekha Sachan Madan Lal Brahma Bhatt Raj Kamal Tripathi Monika Sachdev 《Reports of Biochemistry & Molecular Biology》2022,10(4):711
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms 相似文献
944.
Yuen Ler Chow Shantanu Singh Anne E. Carpenter Gregory P. Way 《PLoS computational biology》2022,18(2)
A variational autoencoder (VAE) is a machine learning algorithm, useful for generating a compressed and interpretable latent space. These representations have been generated from various biomedical data types and can be used to produce realistic-looking simulated data. However, standard vanilla VAEs suffer from entangled and uninformative latent spaces, which can be mitigated using other types of VAEs such as β-VAE and MMD-VAE. In this project, we evaluated the ability of VAEs to learn cell morphology characteristics derived from cell images. We trained and evaluated these three VAE variants—Vanilla VAE, β-VAE, and MMD-VAE—on cell morphology readouts and explored the generative capacity of each model to predict compound polypharmacology (the interactions of a drug with more than one target) using an approach called latent space arithmetic (LSA). To test the generalizability of the strategy, we also trained these VAEs using gene expression data of the same compound perturbations and found that gene expression provides complementary information. We found that the β-VAE and MMD-VAE disentangle morphology signals and reveal a more interpretable latent space. We reliably simulated morphology and gene expression readouts from certain compounds thereby predicting cell states perturbed with compounds of known polypharmacology. Inferring cell state for specific drug mechanisms could aid researchers in developing and identifying targeted therapeutics and categorizing off-target effects in the future. 相似文献
945.
Animesh Sarker Abhishek Singh Rathore Md Fahim Khalid Rinkoo Devi Gupta 《The Journal of biological chemistry》2022,298(4)
Dengue is one of the most dominant arthropod-borne viral diseases, infecting at least 390 million people every year throughout the world. Despite this, there is no effective treatment against dengue, and the only available vaccine has already been withdrawn owing to the significant adverse effects. Therefore, passive immunotherapy using monoclonal antibodies is now being sought as a therapeutic option. To date, many dengue monoclonal antibodies have been identified, most of which are serotype-specific, and only a few of which are cross-reactive. Furthermore, antibodies that cross-react within serotypes are weakly neutralizing and frequently induce antibody-dependent enhancement, which promotes viral entry and replication. Therefore, broadly neutralizing antibodies with no risk of antibody-dependent enhancement are required for the treatment of dengue. Here, we developed a single-chain variable fragment (scFv) antibody from an anti-fusion loop E53 antibody (PDB: 2IGF). We introduced previously predicted favorable complementarity-determining region (CDR) mutations into the gene encoding the scFv antibody for affinity maturation, and the resultant variants were tested in vitro against the highly conserved fusion and bc epitope of the dengue virus envelope protein. We show some of these scFv variants with two to three substitution mutations in three different CDRs possess affinity constants (KD) ranging from 20 to 200 nM. The scFv-mutant15, containing D31L, Y105W, and S227W substitutions, showed the lowest affinity constant, (KD = 24 ± 7 nM), approximately 100-fold lower than its parental construct. We propose that the scFv-derivative antibody may be a good candidate for the development of an effective and safe immunotherapy. 相似文献
946.
Singh A. Amala Mithin Minther Arul Franco P. Binoj J. S. Sahaya Elsi S. Divin Kumar M. 《Plasmonics (Norwell, Mass.)》2019,14(3):595-610
Plasmonics - Corrosion is a natural process which gradually destructs the materials with their environment by chemical or electrochemical means. Mechanized boat hull structures used in fishing were... 相似文献
947.
948.
B Dhar B D Singh R B Singh J S Srivastava V P Singh R M Singh 《Acta microbiologica Polonica》1979,28(4):319-324
Soil samples from 30 fields in neighbouring districts of Varanasi were screened for rhizobiophages on 60 Rhizobium strains. Plaques were observed on five strains: P1, P5, SU391 (R. leguminosarum), CB756 and 32H1 (Rhizobium sp.). Rhizobiophages infective on one or more of the five strains were present in all fields. There seems to be no correlation between presence of phage and the standing crop or the pH (7.1-8.2) of the soil. Eight distinct rhizobiophages have been isolated and characterized for host specificity, plaque morphology and maximum titer in broth. 相似文献
949.
950.
Purification of chloroplast cytochrome b 559 总被引:1,自引:0,他引:1
H S Garewal J Singh A R Wasserman 《Biochemical and biophysical research communications》1971,44(6):1300-1305