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121.
Molecular and Cellular Biochemistry - Pregnancy is a challenging physiological process that involves maternal adaptations to the increasing energetics demands imposed by the growing conceptus.... 相似文献
122.
Molecular Biology Reports - Research activities aiming to investigate the genetic diversity are very crucial because they provide information for the breeding and germplasm conservation activities.... 相似文献
123.
Srinivasan Raj Samuel Syed Kuduruthullah Al Moutassem Billah Khair Maher Al Shayeb Abed Elkaseh Sudhir Rama Varma Gulrez Nadeem Issameldin Abdalla Elkhader Awad Ashekhi 《Saudi Journal of Biological Sciences》2021,28(1):492-494
Corona virus disease (COVID-19) has crippled life, families and oral health care delivery. Hence, we assessed the impact of dental pain, fear of COVID-19 and psychological distress during lockdown on the oral health related quality of life of individuals visiting a tertiary dental care center during COVID-19 pandemic. Cross sectional study conducted among patients between 18 and 60 years. Demographics, access to pain killers, dental care (yes/no), duration (</> 15 days) and intensity of pain were self reported. Fear of COVID-19 was assessed using fear of corona virus scale (FCV-19S); psychological distress in the last 30 days and oral health related quality of life was evaluated. Oral examination was performed and dental caries status (DMFT) was assessed using the world health organization method. Univariate and multivariate regression analysis was conducted to evaluate significant predictors and 5% was set as level of significance. 2966 patients visited our dental emergency due to painful decayed tooth between March-June 2020. Mean age was 42.7 years, 53.97% were males and most common cause of painful teeth was upper right third molar (7.7%). 73.4% reported lack of pain medication; 95% reported closure of dental clinics close to home. Almost 79% suffered from dental pain for >15 days. Higher self reported pain (OR 2.1; 95% CI 1.36–14.71), >15 days of suffering from pain (OR 6.8; 95% CI 2.18–23.14), greater fear of COVID-19 (OR 4.14; 95% CI 1.98–16.07) and psychological distress (OR 4.41; 95% CI 1.09–16.76) were associated with poorer OHRQOL of adults during COVID-19 pandemic. Our findings strongly suggest that COVID-19 pandemic negatively impacts the mental and oral health of individuals affecting their overall health. 相似文献
124.
Nonenzymatic glycation of macromolecules, especially proteins, takes place mainly due to hyperglycemia in diabetes mellitus. Increased glycolysis during cancer and inflammation during rheumatoid arthritis also contribute to the process of glycation. As lysine residues of proteins are a potential site for glycation, it could be used as a marker for early glycation induced changes in lysine-rich proteins. In the present study, a lysine polymer was incubated with increasing concentrations of glucose for 24 h, and the early glycation product was evaluated by nitroblue tetrazolium assay. The modified polymer together with unmodified one was characterized by gel electrophoresis and UV, fluorescence spectroscopy. Results of the study clearly demonstrate that structural perturbation in the lysine polymer was caused by the early glycation. Further study on detection of antibodies against theglycated proteins in diseased patients might be helpful in early diagnosis of the disease. 相似文献
125.
Kaakoush NO Deshpande NP Wilkins MR Tan CG Burgos-Portugal JA Raftery MJ Day AS Lemberg DA Mitchell H 《PloS one》2011,6(12):e29045
Campylobacter concisus has garnered increasing attention due to its association with intestinal disease, thus, the pathogenic potential of strains isolated from different intestinal diseases was investigated. A method to isolate C. concisus was developed and the ability of eight strains from chronic and acute intestinal diseases to adhere to and invade intestinal epithelial cells was determined. Features associated with bacterial invasion were investigated using comparative genomic analyses and the effect of C. concisus on host protein expression was examined using proteomics. Our isolation method from intestinal biopsies resulted in the isolation of three C. concisus strains from children with Crohn's disease or chronic gastroenteritis. Four C. concisus strains from patients with chronic intestinal diseases can attach to and invade host cells using mechanisms such as chemoattraction to mucin, aggregation, flagellum-mediated attachment, "membrane ruffling", cell penetration and damage. C. concisus strains isolated from patients with chronic intestinal diseases have significantly higher invasive potential than those from acute intestinal diseases. Investigation of the cause of this increased pathogenic potential revealed a plasmid to be responsible. 78 and 47 proteins were upregulated and downregulated in cells infected with C. concisus, respectively. Functional analysis of these proteins showed that C. concisus infection regulated processes related to interleukin-12 production, proteasome activation and NF-κB activation. Infection with all eight C. concisus strains resulted in host cells producing high levels of interleukin-12, however, only strains capable of invading host cells resulted in interferon-γ production as confirmed by ELISA. These findings considerably support the emergence of C. concisus as an intestinal pathogen, but more significantly, provide novel insights into the host immune response and an explanation for the heterogeneity observed in the outcome of C. concisus infection. Moreover, response to infection with invasive strains has substantial similarities to that observed in the inflamed mucosa of Crohn's disease patients. 相似文献
126.
Stefan F. Schreier Irene Suomi Peter Bröde Herbert Formayer Harald E. Rieder Imram Nadeem Gerd Jendritzky Ekaterina Batchvarova Philipp Weihs 《International journal of biometeorology》2013,57(2):207-223
In this study we examine the determination accuracy of both the mean radiant temperature (Tmrt) and the Universal Thermal Climate Index (UTCI) within the scope of numerical weather prediction (NWP), and global (GCM) and regional (RCM) climate model simulations. First, Tmrt is determined and the so-called UTCI-Fiala model is then used for the calculation of UTCI. Taking into account the uncertainties of NWP model (among others the HIgh Resolution Limited Area Model HIRLAM) output (temperature, downwelling short-wave and long-wave radiation) stated in the literature, we simulate and discuss the uncertainties of Tmrt and UTCI at three stations in different climatic regions of Europe. The results show that highest negative (positive) differences to reference cases (under assumed clear-sky conditions) of up to ?21°C (9°C) for Tmrt and up to ?6°C (3.5°C) for UTCI occur in summer (winter) due to cloudiness. In a second step, the uncertainties of RCM simulations are analyzed: three RCMs, namely ALADIN (Aire Limitée Adaptation dynamique Développement InterNational), RegCM (REGional Climate Model) and REMO (REgional MOdel) are nested into GCMs and used for the prediction of temperature and radiation fluxes in order to estimate Tmrt and UTCI. The inter-comparison of RCM output for the three selected locations shows that biases between 0.0 and ±17.7°C (between 0.0 and ±13.3°C) for Tmrt (UTCI), and RMSE between ±0.5 and ±17.8°C (between ±0.8 and ±13.4°C) for Tmrt (UTCI) may be expected. In general the study shows that uncertainties of UTCI, due to uncertainties arising from calculations of radiation fluxes (based on NWP models) required for the prediction of Tmrt, are well below ±2°C for clear-sky cases. However, significant higher uncertainties in UTCI of up to ±6°C are found, especially when prediction of cloudiness is wrong. 相似文献
127.
Lea Vacca Michel Joy Snyder Rachel Schmidt Jennifer Milillo Kyle Grimaldi Breanna Kalmeta M. Nadeem Khan Sharad Sharma Leslie Kate Wright Michael E. Pichichero 《Journal of bacteriology》2013,195(14):3252-3259
The majority of outer membrane (OM) lipoproteins in Gram-negative bacteria are tethered to the membrane via an attached lipid moiety and oriented facing in toward the periplasmic space; a few lipoproteins have been shown to be surface exposed. The outer membrane lipoprotein P6 from the Gram-negative pathogenic bacterium nontypeable Haemophilus influenzae (NTHi) is surface exposed and a leading vaccine candidate for prevention of NTHi infections. However, we recently found that P6 is not a transmembrane protein as previously thought (L. V. Michel, B. Kalmeta, M. McCreary, J. Snyder, P. Craig, M. E. Pichichero, Vaccine 29:1624–1627, 2011). Here we pursued studies to show that P6 has a dual orientation, existing infrequently as surface exposed and predominantly as internally oriented toward the periplasmic space. Flow cytometry using three monoclonal antibodies with specificity for P6 showed surface staining of whole NTHi cells. Confocal microscopy imaging confirmed that antibodies targeted surface-exposed P6 of intact NTHi cells and not internal P6 in membrane-compromised or dead cells. Western blots of two wild-type NTHi strains and a mutant NTHi strain that does not express P6 showed that P6 antibodies do not detect a promiscuous epitope on NTHi. Depletion of targets to nonlipidated P6 significantly decreased bactericidal activity of human serum. Protease digestion of surface-exposed P6 demonstrated that P6 is predominantly internally localized in a manner similar to its homologue Pal in Escherichia coli. We conclude that P6 of NTHi is likely inserted into the OM in two distinct orientations, with the predominant orientation facing in toward the periplasm. 相似文献
128.
Greco Hernández Mathieu Miron Hong Han Niankun Liu Jérémy Magescas Gritta Tettweiler Filipp Frank Nadeem Siddiqui Nahum Sonenberg Paul Lasko 《Molecular and cellular biology》2013,33(15):2854-2864
Translation is a fundamental step in gene expression, and translational control is exerted in many developmental processes. Most eukaryotic mRNAs are translated by a cap-dependent mechanism, which requires recognition of the 5′-cap structure of the mRNA by eukaryotic translation initiation factor 4E (eIF4E). eIF4E activity is controlled by eIF4E-binding proteins (4E-BPs), which by competing with eIF4G for eIF4E binding act as translational repressors. Here, we report the discovery of Mextli (Mxt), a novel Drosophila melanogaster 4E-BP that in sharp contrast to other 4E-BPs, has a modular structure, binds RNA, eIF3, and several eIF4Es, and promotes translation. Mxt is expressed at high levels in ovarian germ line stem cells (GSCs) and early-stage cystocytes, as is eIF4E-1, and we demonstrate the two proteins interact in these cells. Phenotypic analysis of mxt mutants indicates a role for Mxt in germ line stem cell (GSC) maintenance and in early embryogenesis. Our results support the idea that Mxt, like eIF4G, coordinates the assembly of translation initiation complexes, rendering Mxt the first example of evolutionary convergence of eIF4G function. 相似文献
129.
Giovanni Dinelli Ilaria Marotti Pietro Catizone Sara Bosi Asif Tanveer Rana Nadeem Abbas Danijela Pavlovic 《Central European Journal of Biology》2013,8(3):286-296
The germination ecology of Ambrosia artemisiifolia and A. trifida glyphosate susceptible biotypes sampled in marginal areas, was compared with that of the same species but different biotypes suspected of glyphosate resistance, common and giant ragweed, respectively. The suspected resistant biotypes were sampled in Roundup Ready® soybean fields. Within each weed species, the seeds of the biotype sampled in marginal area were significantly bigger and heavier than those of the biotype sampled in the soybean fields. A. artemisiifolia biotypes exhibited a similar dormancy and germination, while differences between A. trifida biotypes were observed. A. artemisiifolia biotypes showed similar threshold temperature for germination, whereas, the threshold temperature of the susceptible A. trifida biotype was half as compared to that of the resistant A. trifida biotype. No significant differences in emergence as a function of sowing depth were observed between susceptible A. artemisiifolia and suspected resistant A. trifida biotype, while at a six-cm seedling depth the emergence of the A. artemisiifolia susceptible biotype was 2.5 times higher than that of the A. trifida suspected resistant biotype. This study identified important differences in seed germination between herbicide resistant and susceptible biotypes and relates this information to the ecology of species adapted to Roundup Ready® fields. Information obtained in this study supports sustainable management strategies, with continued use of glyphosate as a possibility. 相似文献
130.
Jenkins W Perone P Walker K Bhagavathula N Aslam MN DaSilva M Dame MK Varani J 《Biological trace element research》2011,144(1-3):621-635
The purpose of this study was to compare each of the 14 naturally occurring lanthanoid metal ions for ability to stimulate pro-fibrotic responses in human dermal fibroblasts. When fibroblasts were exposed to individual lanthanoids over the concentration range of 1-100?μM, increased proliferation was observed with each of the agents as compared with control cells that were already proliferating rapidly in a growth factor-enriched culture medium. Dose-response differences were observed among the individual metal ions. Matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 levels were also increased in response to lanthanoid exposure but type I procollagen production was not. A dose-response relationship between induction of proliferation and increased MMP-1 was observed. Non-lanthanoid transition metal ions (aluminum, copper, cobalt, iron, magnesium, manganese, nickel, and zinc) were examined in the same assays; there was little stimulation with any of these metals. When epidermal keratinocytes were examined in place of dermal fibroblasts, there was no growth stimulation with any of the lanthanoids. Several of the lanthanoid metals inhibited keratinocyte proliferation at higher concentrations (50-100?μM). 相似文献