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81.
Swati Garg Shalini Agarwal Surbhi Dabral Naveen Kumar Seema Sehrawat Shailja Singh 《Systems and synthetic biology》2015,9(1):23-26
Malaria, a leading parasitic killer, is caused by Plasmodium spp. The pathology of the disease starts when Plasmodium merozoites infect erythrocytes to form rings, that matures through a large trophozoite form and develop into schizonts containing multiple merozoites. The number of intra-erythrocytic merozoites is a key-determining factor for multiplication rate of the parasite. Counting of intraerythrocytic merozoites by classical 2-D microscopy method is error prone due to insufficient representation of merozoite in one optical plane of a schizont. Here, we report an alternative 3-D microscopy based automated method for counting of intraerythrocytic merozoites in entire volume of schizont. This method offers a considerable amount of advantages in terms of both, ease and accuracy. 相似文献
82.
Effect of alcoholic extract of roots of Rubia cordifolia was studied on elevated blood glucose level in alloxan treated animals. The extract reduced the blood sugar level raised by alloxan. Effect of alcoholic extract was also investigated on cold restraint induced stress and on scopolamine-induced memory impairment. Alcoholic extract enhanced brain gamma-amino-n-butyric acid (GABA) levels and decreased brain dopamine and plasma corticosterone levels. Acidity and ulcers caused due to cold restraint stress were inhibited by alcoholic extract. Animals treated with alcoholic extract spent more time in open arm in elevated plus maze model. It also antagonized scopolamine induced learning and memory impairment. Baclofen induced catatonia was potentiated by alcoholic extract. 相似文献
83.
84.
Swati Singh Divya Bhatt Munmun Kumar Singh Velusamy Sundaresan Sudeep Tandon Rajendra Chandra Padalia Dnyaneshwar Umrao Bawankule Ram Swaroop Verma 《化学与生物多样性》2021,18(11):e2100531
Artemisia pallens Wall. ex DC., popularly known as davana, has gained considerable attention because of its unique fragrance, high economic value, and pharmacological properties. The compositional complexity of davana essential oil (DO) has been a challenge for quality control. In this study, the chemical profile of DO was developed using polarity-based fractionation and a combination of gas chromatographic (GC-FID), hyphenated chromatographic (GC/MS), and spectroscopic (Fourier-Transform Infra-Red, 1D, 2D-Nuclear Magnetic Resonance) techniques. The analysis led to the identification of ninety-nine compounds. Major components of the DO were cis-davanone (D3, 53.0 %), bicyclogermacrene (6.9 %), trans-ethyl cinnamate (4.9 %), davana ether isomer (3.4 %), spathulenol (2.8 %), cis-hydroxy davanone (2.4 %), and trans-davanone (2.1 %). The study led to identifying several co-eluting novel minor components, which could help determine the authenticity of DO. The rigorous column-chromatography led to the isolation of five compounds. Among these, bicyclogermacrene, trans-ethyl cinnamate, and spathulenol were isolated and characterized by spectroscopic methods for the first time from DO. Pharmacological profile revealed that the treatment of DO and D3 inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6) induced by lipopolysaccharide (LPS) in primary macrophages without any cytotoxic effect after administration of their effective concentrations. The result of this study indicates the suitability of DO and D3 for further investigation for the treatment of chronic skin inflammatory conditions. 相似文献
85.
A non-specific protease, subtilisin, was used to probe the existence of folded structure in thermal aggregates of bovine carbonic
anhydrase-II (BCA). BCA aggregates and native BCA were subjected to proteolysis and electrophoretic analyses which revealed
the accumulation of polypeptide fragments of similar size, indicating survival of similar sections of folded structure burying
peptide bonds away from scission in the two samples. N-terminal sequencing revealed that the termini of size-matched fragments
from the two samples were either identical, or located very close to each other, and predominantly on the surface of the 3-dimensional
structure of native BCA. The susceptibility to proteolysis of very nearly the same sites in the two samples suggests that
native-like elements of structure survive within BCA aggregates. The finding that thermal aggregation can involve interactions
among molecules retaining elements of native-like structure, suggests that complete chain unfolding may not be a necessary
prerequisite for all aggregation. 相似文献
86.
In this study, the kinetics of degradation of caffeine and related methylxanthines by induced cells of Pseudomonas sp. was performed. The kinetics data showed that degradation of caffeine, theobromine, and 7-methylxanthine followed Michealis–Menten
kinetics. The values of K
m
are low for caffeine and 7-methylxanthine and high for theobromine. Degradation of caffeine and theobromine was enhanced
in the presence of NADH and NADPH, whereas the degradation of 7-methylxanthine was unaffected. Among the various metal ions
tested, Fe2+ was found to enhance the rate of degradation for all three substrates, whereas Zn2+ and Cu2+ inhibited the degradation of caffeine and theobromine but not 7-methylxanthine. The differences in kinetic parameters and
cofactor requirement suggest the possibility of the involvement of more than one N-demethylases in the caffeine catabolic
pathway in Pseudomonas sp. The induced cells can serve as effective biocatalysts for the development of biodecaffeination techniques. 相似文献
87.
Vaish Swati Parveen Reshma Rajneesh Singh Nootan Gupta Divya Basantani Mahesh Kumar 《Journal of plant research》2022,135(6):823-852
Journal of Plant Research - Plant glutathione S-transferases are an ancient protein superfamily having antioxidant activity. These proteins are primarily involved in diverse plant functions such as... 相似文献
88.
89.
Trypanosomatids are typified by uniquely configured mitochondrial DNA--the kinetoplast. The replication timing of kinetoplast DNA (kDNA) is closely linked to nuclear S phase, but nuclear and kinetoplast compartments display staggered timing of segregation, post-replication. Kinetoplast division is completed before nuclear division in Trypanosoma species while nuclear division is completed first in Crithidia species. Leishmania donovani is the causative agent of visceral leishmaniasis, a form of leishmanial infection that is often fatal. Cell cycle related studies in Leishmania are hampered by difficulties in synchronizing these cells. This report examines the replication/segregation pattern and morphology of the kinetoplast in L. donovani with the aim of determining if these traits can be used to assign cell cycle stage to individual cells. By labeling replicating cells with bromodeoxyuridine after synchronization with hydroxyurea, we find that although both nuclear and kDNA initiate replication in early S phase, nuclear division precedes kinetoplast segregation in 80% of the cells. The kinetoplast is roundish/short rod-like in G1 and in early to mid-S phase, but prominently elongated/bilobed in late S phase and early G2/M. These morphological traits and segregation pattern of the kinetoplast can be used as a marker for cell cycle stage in a population of asynchronously growing L. donovani promastigotes, in place of cell synchronization procedures or instead of using antibody staining for cell cycle stage marker proteins. 相似文献
90.