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821.
Raina N. Fichorova Hidemi S. Yamamoto Titilayo Fashemi Evan Foley Stanthia Ryan Noah Beatty Hassan Dawood Gary R. Hayes Guillaume St-Pierre Sachiko Sato Bibhuti N. Singh 《The Journal of biological chemistry》2016,291(2):998-1013
Trichomoniasis is the most common non-viral sexually transmitted infection caused by the vaginotropic extracellular protozoan parasite Trichomonas vaginalis. The infection is recurrent, with no lasting immunity, often asymptomatic, and linked to pregnancy complications and risk of viral infection. The molecular mechanisms of immune evasion by the parasite are poorly understood. We demonstrate that galectin-1 and -3 are expressed by the human cervical and vaginal epithelial cells and act as pathogen-recognition receptors for the ceramide phosphoinositol glycan core (CPI-GC) of the dominant surface protozoan lipophosphoglycan (LPG). We used an in vitro model with siRNA galectin knockdown epithelial clones, recombinant galectins, clinical Trichomonas isolates, and mutant protozoan derivatives to dissect the function of galectin-1 and -3 in the context of Trichomonas infection. Galectin-1 suppressed chemokines that facilitate recruitment of phagocytes, which can eliminate extracellular protozoa (IL-8) or bridge innate to adaptive immunity (MIP-3α and RANTES (regulated on activation normal T cell expressed and secreted)). Silencing galectin-1 increased and adding exogenous galectin-1 suppressed chemokine responses to Trichomonas or CPI-GC/LPG. In contrast, silencing galectin-3 reduced IL-8 response to LPG. Live Trichomonas depleted the extracellular levels of galectin-3. Clinical isolates and mutant Trichomonas CPI-GC that had reduced affinity to galectin-3 but maintained affinity to galectin-1 suppressed chemokine expression. Thus via CPI-GC binding, Trichomonas is capable of regulating galectin bioavailability and function to the benefit of its parasitic survival. These findings suggest novel approaches to control trichomoniasis and warrant further studies of galectin-binding diversity among clinical isolates as a possible source for symptom disparity in parasitic infections. 相似文献
822.
gamma-Glutamyl transpeptidase (gamma-GT) activity in various organs of mice during ontogenesis has been determined. The activity profile in foetus, neonates and the adult animal were compared to ascertain the functional significance of the enzyme. In addition, the effect of cortisol on gamma-GT activity in adult kidney is presented. 相似文献
823.
Preeti Gupta Ritu Verma Anita Kamra Verma Pratima Chaudhuri Chattopadhyay 《Biochemistry and Biophysics Reports》2020
BackgroundProteins have tendency to form inactive aggregates at higher temperatures due to thermal instability. Maintenance of thermal stability is essential to gain the protein in sufficient quantity and biologically active form during their commercial production.MethodsBL21-DE3 Rosetta E. coli cells which contains plasmid pET43.1a vector was used for producing zDHFR protein commercially. The purification of N-terminal Histidine tagged zDHFR was performed by Immobilized Metal Ion chromatography (IMAC). Investigations were performed in existence and non existence of Silver nanoparticles (AgNPs). The inactivation kinetics of zDHFR in existence and non existence of AgNPs were monitored over a range of 40–80 °C as monitored by UV–Visible absorption spectroscopy.ResultsThe protein completely lost its activity at 55 °C. Kinetics of inactivated zDHFR follows first order model in presence and absence of AgNPs. Decrease in rate constant (k) values at respective temperatures depicts that AgNPs contribute in the thermostability of the protein. AgNPs also assists in regaining the activity of zDHFR protein.ConclusionsAgNPs helps in maintaining thermostability and reducing the aggregation propensity of zDHFR protein.General significanceResult explains that AgNPs are recommended as a valuable system in enhancing the industrial production of biologically active zDHFR protein which is an important component in folate cycle and essential for survival of cells and prevents the protein from being aggregated. 相似文献
824.
One hundred and fifteen strains ofMoraxella catarrhalis from inpatients and healthy children were collected from 2000 to 2005. MICs to 17 antimicrobial agents from different groups were determined. High resistance rate to penicillin G, aminopenicillins and first generation cephalosporins (98.26%) was found. Susceptibility to cefuroxime, cefotaxime and ceftriaxone was from 86.08 to 97.40%. AllM. catarrhalis strains were susceptible to aminopenicillin/inhibitor combinations, ceftazidime, ceftibuten, ciprofloxacin and gentamicin. The susceptibility rates to azithromycin, clarithromycin, tetracycline and trimethoprim/sulfamethoxazole were reduced in range of 6–9%. Presence ofbro1 orbro2 genes was revealed in 113M. catarrhalis strains by PCR. The overall prevalence of the BRO-1 and BRO-2 enzymes was 92.92 and 7.08% respectively. MICs of Penicllin were significantly higher inbro1 positive isolates. 相似文献
825.
826.
Research examining the association between exposure to a wide range of adverse childhood experiences (ACEs) and accelerated biological aging in older adults is limited. The purpose of this study was to examine the association of ACEs, both as a cumulative score and individual forms of adversity, with epigenetic age acceleration assessed using the DNA methylation (DNAm) GrimAge and DNAm PhenoAge epigenetic clocks in middle and older-aged adults. This cross-sectional study analyzed baseline and first follow-up data on 1445 participants aged 45–85 years from the Canadian Longitudinal Study on Aging (CLSA) who provided blood samples for DNAm analysis. ACEs were assessed using a validated self-reported questionnaire. Epigenetic age acceleration was estimated by regressing each epigenetic clock estimate on chronological age. Cumulative ACEs score was associated with higher DNAm GrimAge acceleration (β: 0.07; 95% CI: 0.02, 0.11) after adjusting for covariates. Childhood exposure to parental separation or divorce (β: 0.06; 95% CI: 0.00, 0.11) and emotional abuse (β: 0.06; 95% CI: 0.00, 0.12) were associated with higher DNAm GrimAge acceleration after adjusting for other adversities and covariates. There was no statistical association between ACEs and DNAm PhenoAge acceleration. Early life adversity may become biologically embedded and lead to premature biological aging, in relation to DNAm GrimAge, which estimates risk of mortality. Strategies that increase awareness of ACEs and promote healthy child development are needed to prevent ACEs. 相似文献
827.
Sushma Koul Vishal Raina Sham Krishen Sharma 《Journal of plant biochemistry and biotechnology.》2005,14(1):57-59
The micropropagation of H.spicatum, a medicinal and aromatic plant was investigated as an option for conservation and propagation, as wild populations are fast depleting. The source of raw material is rhizomes of plants that are collected from the wild. There is no planned cultivation of the plant. Multiple shoot cultures were established on MS medium supplemented with BAP and IAA from the pre-existing buds on the rhizome. Prolonged cultivation on the same medium or transfer to hormone free medium induced roots/rhizome formation; liquid medium proved more suitable. Greenhouse hardened plants were transferred to field. A successful protocol with 99% root formation and 80–85.5% field survival has been formulated. 相似文献