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91.
92.
Mohini Tiwary Nipanshu Agarwal Amit Dinda Subhash C. Yadav 《Molecular biology reports》2016,43(5):349-358
Overexpression of domains of a human protein using recombinant DNA technology has been challenging because individual domains intend to accumulate as non-soluble aggregate when expressed separately. Studies on identifying right sequences for a domain to be able to fold independently may help understand the folding pattern and underlying protein-engineering events to isolate the functional domains of a protein. In this report, individual domains of prostate cancer related biomarkers; MSMB and PSA were overexpressed in bacterial system and purified in their folded forms using affinity chromatography. The western blotting experiment using domain specific antibodies further confirmed these proteins. The designed nucleotide sequences domains were truncated using fold index software and folding were predicted by phyre2 and I-TASSER software. Other parameters were optimized for their overexpression and purification using Co-NTA affinity chromatography. Purified domains of each protein showed secondary structures such as α + β type for PSA, α/β and β type for the each domains of PSA and MSMB respectively. This is the first report on producing PSA and MSMB individual domains in functional folded forms. This study may help produce the folded domain of many such proteins to be used for better diagnostic purpose. 相似文献
93.
C S Narayanan J Fujimoto E Geras-Raaka M C Gershengorn 《The Journal of biological chemistry》1992,267(24):17296-17303
In rat pituitary GH3 cells, thyrotropin-releasing hormone (TRH) down-regulates TRH receptor (TRH-R) mRNA (Fujimoto, J., Straub, R.E., and Gershengorn, M.C. (1991) Mol. Endocrinol. 5, 1527-1532), at least in part, by stimulating its degradation (Fujimoto, J., Narayanan, C.S., Benjamin, J.E., Heinflink, M., and Gershengorn, M.C. (1992) Endocrinology 130, 1879-1884). Here we show that TRH regulates RNase activity in GH3 cells and that specific mRNA sequences are needed for in vivo regulation of TRH-R mRNA by TRH. TRH affected RNase activity in a biphasic manner with rapid stimulation (by 10 min) followed by a decrease to a rate slower than in control lysates within 6 h. This time course paralleled the effects of TRH on degradation of TRH-R mRNA in vivo. The regulated RNase activity was in a polysome-free fraction of the lysates and was not specific for TRH-R RNA. A truncated form of TRH-R RNA that was missing the entire 3'-untranslated region (TRHR-R5) was more stable than full-length TRH-R RNA (TRHR-WT). In contrast to TRHR-WT mRNA, TRHR-R5 mRNA and TRHR-D9 mRNA, which was missing the 143 nucleotides 5' of the poly(A) tail, were not down-regulated by TRH in stably transfected GH3 cells as their rates of degradation were not increased. These data show that TRH regulates RNase activity in GH3 cells, that the 3'-untranslated region bestows decreased stability on TRH-R mRNA and that the 3' end of the mRNA is necessary for regulation by TRH of TRH-R mRNA degradation. We present an hypothesis that explains specific regulation of TRH-R mRNA degradation by TRH in GH3 pituitary cells. 相似文献
94.
Ma Tao Kandhare Amit D. Mukherjee-Kandhare Anwesha A. Bodhankar Subhash L. 《Molecular biology reports》2019,46(1):105-118
Molecular Biology Reports - Doxorubicin (DOX) is a widely used anthracycline antibiotic for the management of carcinoma. However, it is associated with cardiotoxicity. Fisetin is a plant flavonoid... 相似文献
95.
We address the hypothesis that postures adopted during grammatical pauses in speech production are more “mechanically advantageous” than absolute rest positions for facilitating efficient postural motor control of vocal tract articulators. We quantify vocal tract posture corresponding to inter-speech pauses, absolute rest intervals as well as vowel and consonant intervals using automated analysis of video captured with real-time magnetic resonance imaging during production of read and spontaneous speech by 5 healthy speakers of American English. We then use locally-weighted linear regression to estimate the articulatory forward map from low-level articulator variables to high-level task/goal variables for these postures. We quantify the overall magnitude of the first derivative of the forward map as a measure of mechanical advantage. We find that postures assumed during grammatical pauses in speech as well as speech-ready postures are significantly more mechanically advantageous than postures assumed during absolute rest. Further, these postures represent empirical extremes of mechanical advantage, between which lie the postures assumed during various vowels and consonants. Relative mechanical advantage of different postures might be an important physical constraint influencing planning and control of speech production. 相似文献
96.
97.
Aruliah Rajasekar Thambidurai Ganesh Babu Sundaram Maruthamuthu Shunmugiah Thevar Karutha Pandian Sidhan Mohanan Narayanan Palaniswamy 《World journal of microbiology & biotechnology》2007,23(8):1065-1074
A facultative anaerobic species Serratia marcescens ACE2 isolated from the corrosion products of a diesel-transporting pipeline in North West India was identified by 16S rDNA
sequence analysis. The role of Serratia marcesens ACE2 on biodegradation of commercial corrosion inhibitor (CCI) and its influence on the corrosion of API 5LX steel has been
enlightened. The degrading strain ACE2 is involved in the process of corrosion of steel API 5LX and also utilizes the inhibitor
as organic source. The quantitative biodegradation efficiency of corrosion inhibitor was 58%, which was calculated by gas
chromatography mass spectrum analysis. The effect of CCI on the growth of bacteria and its corrosion inhibition efficiency
were investigated. Additionally, the role of this bacterium in corrosion of steel has been investigated by powder X-ray diffractometer
(XRD) and scanning electron microscope studies. The presence of high-intensity ferric oxides and manganese oxides noticed
from the XRD indicates that ACE2 enhances the corrosion process in presence of inhibitor as a carbon source. This basic study
will be useful for the development of new approaches for the detection, monitoring and control of microbial corrosion in petroleum
product pipelines. 相似文献
98.
Zambre AP Kulkarni VM Padhye S Sandur SK Aggarwal BB 《Bioorganic & medicinal chemistry》2006,14(21):7196-7204
Novel curcumin analogs were synthesized using Knoevenagel condensation to convert enolic diketones of curcumin into non-enolizable ones and Schiff bases were prepared using a bioactive thiosemicarbazide pharmacophore. Copper(II) conjugates of all synthesized ligands were prepared and structurally characterized as well as evaluated for their potential of inhibiting TNF-induced NF-kappaB activation and proliferation in human leukemic KBM-5 cells wherein compound 13 was found to be more potent than curcumin. Compounds were further examined on other tumor cell lines such as Jurkat, H1299, and MM1, respectively. 相似文献
99.
Nireeksha Sudhir Rama Varma Marah Damdoum Mohammed Amjed Alsaegh Mithra N. Hegde Suchetha N. Kumari Srinivasan Ramamurthy Jayaraj Narayanan Eisha Imran Juzer Shabbir Zohaib Khurshid 《Current issues in molecular biology》2021,43(1):116
The role of inflammatory mediators in dental pulp is unique. The local environment of pulp responds to any changes in the physiology that are highly fundamental, like odontoblast cell differentiation and other secretory activity. The aim of this review is to assess the role of cathelicidins based on their capacity to heal wounds, their immunomodulatory potential, and their ability to stimulate cytokine production and stimulate immune-inflammatory response in pulp and periapex. Accessible electronic databases were searched to find studies reporting the role of cathelicidins in pulpal inflammation and regeneration published between September 2010 and September 2020. The search was performed using the following databases: Medline, Scopus, Web of Science, SciELO and PubMed. The electronic search was performed using the combination of keywords “cathelicidins” and “dental pulp inflammation”. On the basis of previous studies, it can be inferred that LL-37 plays an important role in odontoblastic cell differentiation and stimulation of antimicrobial peptides. Furthermore, based on these outcomes, it can be concluded that LL-37 plays an important role in reparative dentin formation and provides signaling for defense by activating the innate immune system. 相似文献
100.
Effect of Triphala on oxidative stress and on cell-mediated immune response against noise stress in rats 总被引:2,自引:0,他引:2
Srikumar R Parthasarathy NJ Manikandan S Narayanan GS Sheeladevi R 《Molecular and cellular biochemistry》2006,283(1-2):67-74
Stress is one of the basic factors in the etiology of number of diseases. The present study was aimed to investigate the effect
of Triphala (Terminalia chebula, Terminalia belerica and Emblica officinalis) on noise-stress induced alterations in the antioxidant status and on the cell-mediated immune response in Wistar strain
male albino rats. Noise-stress employed in this study was 100 dB for 4 h/d/15 days and Triphala was used at a dose of 1 g/kg/b.w/48
days. Eight different groups of rats namely, non-immunized: control, Triphala, noise-stress, Triphala with noise-stress, and
corresponding immunized groups were used. Sheep red blood cells (5×109 cells/ml) were used to immunize the animals. Biochemical indicators of oxidative stress namely lipid peroxidation, antioxidants
superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), ascorbic acid in plasma and tissues (thymus and
spleen) and SOD, GPx and corticosterone level in plasma were estimated. Cell-mediated immune response namely foot pad thickness
(FPT) and leukocyte migration inhibition (LMI) test were performed only in immunized groups. Results showed that noise-stress
significantly increased the lipid peroxidation and corticosterone level with concomitant depletion of antioxidants in plasma
and tissues of both non-immunized and immunized rats. Noise-stress significantly suppressed the cell-mediated immune response
by decreased FPT with an enhanced LMI test. The supplementation with Triphala prevents the noise-stress induced changes in
the antioxidant as well as cell-mediated immune response in rats. This study concludes that Triphala restores the noise-stress
induced changes may be due to its antioxidant properties. 相似文献