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981.
982.
Jongsoo Jeon Jae-won Kim Dongeun Yong Kyungwon Lee Yunsop Chong 《Journal of virology》2012,86(24):13876-13877
Multidrug-resistant Pseudomonas aeruginosa commonly causes serious nosocomial infections. In this study, a novel lytic bacteriophage belonging to a member of the family Podoviridae, YMC01/01/P52 PAE BP, which infects carbapenem-resistant Pseudomonas aeruginosa, was isolated and characterized. YMC01/01/P52 PAE BP genome was analyzed by whole-genome sequencing and putative function identification. The bacteriophage genome consists of a double-stranded linear DNA genome of 49,381 bp with a GC content of 62.16%. 相似文献
983.
984.
Min Soo Byun Song E. Kim Jinsick Park Dahyun Yi Young Min Choe Bo Kyung Sohn Hyo Jung Choi Hyewon Baek Ji Young Han Jong Inn Woo Dong Young Lee Alzheimer’s Disease Neuroimaging Initiative 《PloS one》2015,10(11)
We aimed to identify and characterize subtypes of Alzheimer’s disease (AD) exhibiting different patterns of regional brain atrophy on MRI using age- and gender-specific norms of regional brain volumes. AD subjects included in the Alzheimer''s Disease Neuroimaging Initiative study were classified into subtypes based on standardized values (Z-scores) of hippocampal and regional cortical volumes on MRI with reference to age- and gender-specific norms obtained from 222 cognitively normal (CN) subjects. Baseline and longitudinal changes of clinical characteristics over 2 years were compared across subtypes. Whole-brain-level gray matter (GM) atrophy pattern using voxel-based morphometry (VBM) and cerebrospinal fluid (CSF) biomarkers of the subtypes were also investigated. Of 163 AD subjects, 58.9% were classified as the “both impaired” subtype with the typical hippocampal and cortical atrophy pattern, whereas 41.1% were classified as the subtypes with atypical atrophy patterns: “hippocampal atrophy only” (19.0%), “cortical atrophy only” (11.7%), and “both spared” (10.4%). Voxel-based morphometric analysis demonstrated whole-brain-level differences in overall GM atrophy across the subtypes. These subtypes showed different progression rates over 2 years; and all subtypes had significantly lower CSF amyloid-β1–42 levels compared to CN. In conclusion, we identified four AD subtypes exhibiting heterogeneous atrophy patterns on MRI with different progression rates after controlling the effects of aging and gender on atrophy with normative information. CSF biomarker analysis suggests the presence of Aβ neuropathology irrespective of subtypes. Such heterogeneity of MRI-based neuronal injury biomarker and related heterogeneous progression patterns should be considered in clinical trials and practice with AD patients. 相似文献
985.
Hong Jun Jeon Young Rong Bang Hye Youn Park Seul A. Kim 《Chronobiology international》2017,34(6):677-686
Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. The present study included a total of 1794 healthy hospital employees, and they completed the Morningness–Eveningness Questionnaire, Connor–Davidson Resilience Scale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Hospital Anxiety and Depression Scale and World Health Organization Quality of Life Scale Abbreviated Version. Subjects with evening type showed lower sleep quality, more daytime sleepiness and physical fatigue than neither types and morning types. Additionally, evening types were more depressed and anxious and reported a poorer quality of life. CT was found to be a significant predictor of sleep quality, but CT was minimally associated with physical fatigue and psychological well-being in the regression analysis. Instead, resilience was substantially related to all of the variables measured. In conclusion, CT independently predicts sleep quality, but the effects of CT on physical fatigue and psychological well-being are negligible compared to those of resilience. 相似文献
986.
Streptococcus pyogenes is commonly found on pharynx, mouth and rarely on skin, lower gastrointestinal tract. It is a potential pathogen causing tonsillitis, pneumonia, endocarditis. The present study was undertaken to study the effects of low shear modeled microgravity on growth, morphology, antibiotic resistance, cross-stress resistance to various stresses and alteration in gene expression of S. pyogenes. The growth analysis performed using UV–Visible spectroscopy indicated decrease in growth of S. pyogenes under low shear modeled microgravity. Morphological analysis by Bio-transmission electron microscopy (TEM), Bio-scanning electron microscopy (SEM) did not reveal much difference between normal and low shear modeled microgravity grown S. pyogenes. The sensitivity of S. pyogenes to antibiotics ampicillin, penicillin, streptomycin, kanamycin, hygromycin, rifampicin indicates that the bacterium is resistant to hygromycin. Further S. pyogenes cultured under low shear modeled microgravity was found to be more sensitive to ampicillin and rifampicin as compared with normal gravity grown S. pyogenes. The bacteria were tested for the acid, osmotic, temperature and oxidative cross stress resistances. The gene expression of S. pyogenes under low shear modeled microgravity analyzed by microarray revealed upregulation of 26 genes and down regulation of 22 genes by a fold change of 1.5. 相似文献
987.
Hyun Soo Lee Romerson D. Dimla Peter G. Schultz 《Bioorganic & medicinal chemistry letters》2009,19(17):5222-5224
The photo-crosslinking amino acid, p-benzoyl-l-phenylalanine (pBpa), was genetically incorporated into Escherichia coli catabolite activator protein (CAP) in bacteria in response to an amber nonsense codon using an orthogonal tRNA/aminoacyl-tRNA synthetase pair. The mutant CAP (CAP-K26Bpa) containing pBpa formed a covalent complex with a DNA fragment containing the consensus operator sequence upon UV irradiation. Because this amino acid can be genetically incorporated into any DNA-binding protein in E. coli, yeast or mammalian cells with minimal perturbation of protein structure, this method should be generally useful for investigating DNA–protein interactions. 相似文献
988.
D Maysinger O Berezovska R Savic P L Soo A Eisenberg 《Biochimica et biophysica acta》2001,1539(3):205-217
An important therapeutic concern is rate and extent of internalization of drugs into cells. Hydrophilic agents often internalize poorly and slowly, and highly lipophilic ones too rapidly. The incorporation of drugs into micelles allows regulation of their internalization parameters, and newly-described block copolymers can be selectively tailored to suit specific drugs. This report compares internalization of Cell Tracker CM-DiI (DiI), a highly lipophilic non-cytotoxic fluorescent probe in common use in biology, from the freely-presented (non-micelle-incorporated) and micelle-incorporated states. DiI was effectively incorporated (>60%) into 25-50 nm diameter spherical micelles made from polycaprolactone-b-polyethylene oxide block copolymer. Confocal microscopy was used to evaluate the internalization of DiI into mixed neuron-glia cultures (2-14 days in vitro, 2DIV-14DIV). Incorporation of DiI into micelles strikingly reduced the rate and extent of its internalization in both 2DIV and 14DIV cultures. Both the age of the cultures and the block copolymer employed to construct the micelles significantly influence the internalization of micelle-incorporated probe. 相似文献
989.
Molecular Biology Reports - We present here on an innovative assay for detecting miRNAs using a uniquely designed specific extension sequence that provides high efficiency and accuracy. This assay... 相似文献
990.