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91.
Synthesis and in vitro activity of new methylenepiperidinyl and methylenepyrrolidinyl oxazolidinone antibacterial agents 总被引:2,自引:0,他引:2
Kim HY Lee JS Cha JH Pae AN Cho YS Chang MH Koh HY 《Bioorganic & medicinal chemistry letters》2003,13(13):2227-2230
We have prepared and evaluated the antibacterial activities of a series of substituted methylenepiperidinyl and methylenepyrrolidinyl oxazolidinones against several gram-positive strains including the resistant strains of Staphyloccus and Enterococcus, such as MRSA, CRSA, MSSA and VRE. Some of them showed comparable or superior in vitro activities (MIC) to vancomycin. 相似文献
92.
Lee JS Cho YS Chang MH Koh HY Chung BY Pae AN 《Bioorganic & medicinal chemistry letters》2003,13(22):4117-4120
A series of isoxazolyl tetrahydropyridinyl oxazolidinones with various substituents at the 3-position of the isoxazole ring have been synthesized and their in vitro antibacterial activities (MIC) were evaluated against several Gram-positive strains including the resistant strains of Staphyloccus and Enterococcus, such as MRSA and VRE. One of the most potent compounds synthesized, 4f, showed comparable or better activity against selected bacterial strains than those of linezolid and vancomycin. 相似文献
93.
Sung Hae Chang Jin Kyun Park Yun Jong Lee Ji Ae Yang Eun Young Lee Yeong Wook Song Eun Bong Lee 《Arthritis research & therapy》2014,16(4)
Introduction
Rheumatic diseases (RDs) are associated with different cancers; however, it is unclear whether particular cancers are more prevalent in certain RDs. In the present study, we examined the relative incidence of several cancers in a single homogeneous cohort of patients with different RDs.Methods
Patients (N = 3,586) diagnosed with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), dermatomyositis (DM) or polymyositis were included. Cancer diagnosis was based on histopathology. The 2008 Korean National Cancer Registry served as the reference for calculating standardized incidence ratios (SIRs).Results
During the follow-up period of 31,064 person-years, 187 patients developed cancer. RA and SLE patients showed an increased risk of non-Hodgkin’s lymphoma (SIR for RA patients = 3.387, 95% confidence interval (CI) = 1.462 to 6.673; SIR for SLE patients = 7.408, 95% CI = 2.405 to 17.287). SLE patients also had a higher risk of cervical cancer (SIR = 4.282, 95% CI = 1.722 to 8.824). SSc patients showed a higher risk of lung cancer (SIR = 4.917, 95% CI = 1.977 to 10.131). Endometrial cancer was increased only in patients with DM (SIR = 30.529, 95% CI = 3.697 to 110.283). RA patients had a lower risk for gastric cancer (SIR = 0.663, 95% CI = 0.327 to 0.998). The mean time between the RD and cancer diagnoses ranged from 0.1 to 16.6 years, with the shortest time observed in patients with DM (2.0 ± 2.1 years).Conclusions
Different RDs are associated with particular cancers. Thus, cancer surveillance tailored to specific RDs might be beneficial.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0428-x) contains supplementary material, which is available to authorized users. 相似文献94.
Limei Ouyang Jeeyun Lee Cheol-Keun Park Mao Mao Yujian Shi Zhuolin Gong Hancheng Zheng Yingrui Li Yonggang Zhao Guangbiao Wang Huiling Fu Jhingook Kim Ho Yeong Lim 《BMC medical genomics》2014,7(1):1-13
Background
To gain biological insights into lung metastases from hepatocellular carcinoma (HCC), we compared the whole-genome sequencing profiles of primary HCC and paired lung metastases.Methods
We used whole-genome sequencing at 33X-43X coverage to profile somatic mutations in primary HCC (HBV+) and metachronous lung metastases (> 2 years interval).Results
In total, 5,027-13,961 and 5,275-12,624 somatic single-nucleotide variants (SNVs) were detected in primary HCC and lung metastases, respectively. Generally, 38.88-78.49% of SNVs detected in metastases were present in primary tumors. We identified 65–221 structural variations (SVs) in primary tumors and 60–232 SVs in metastases. Comparison of these SVs shows very similar and largely overlapped mutated segments between primary and metastatic tumors. Copy number alterations between primary and metastatic pairs were also found to be closely related. Together, these preservations in genomic profiles from liver primary tumors to metachronous lung metastases indicate that the genomic features during tumorigenesis may be retained during metastasis.Conclusions
We found very similar genomic alterations between primary and metastatic tumors, with a few mutations found specifically in lung metastases, which may explain the clinical observation that both primary and metastatic tumors are usually sensitive or resistant to the same systemic treatments. 相似文献95.
Shun Kamoi Christopher Pretty Paul Docherty Dougie Squire James Revie Yeong Shiong Chiew Thomas Desaive Geoffrey M. Shaw J. Geoffrey Chase 《PloS one》2014,9(7)
Introduction
Accurate, continuous, left ventricular stroke volume (SV) measurements can convey large amounts of information about patient hemodynamic status and response to therapy. However, direct measurements are highly invasive in clinical practice, and current procedures for estimating SV require specialized devices and significant approximation.Method
This study investigates the accuracy of a three element Windkessel model combined with an aortic pressure waveform to estimate SV. Aortic pressure is separated into two components capturing; 1) resistance and compliance, 2) characteristic impedance. This separation provides model-element relationships enabling SV to be estimated while requiring only one of the three element values to be known or estimated. Beat-to-beat SV estimation was performed using population-representative optimal values for each model element. This method was validated using measured SV data from porcine experiments (N = 3 female Pietrain pigs, 29–37 kg) in which both ventricular volume and aortic pressure waveforms were measured simultaneously.Results
The median difference between measured SV from left ventricle (LV) output and estimated SV was 0.6 ml with a 90% range (5th–95th percentile) −12.4 ml–14.3 ml. During periods when changes in SV were induced, cross correlations in between estimated and measured SV were above R = 0.65 for all cases.Conclusion
The method presented demonstrates that the magnitude and trends of SV can be accurately estimated from pressure waveforms alone, without the need for identification of complex physiological metrics where strength of correlations may vary significantly from patient to patient. 相似文献96.
Hae Jin Jeong Sung Yeon Lee Nam Seon Kang Yeong Du Yoo An Suk Lim Moo Joon Lee Hyung Seop Kim Wonho Yih Hiroshi Yamashita Todd C. LaJeunesse 《The Journal of eukaryotic microbiology》2014,61(1):75-94
Dinoflagellates in the genus Symbiodinium are ubiquitous in shallow marine habitats where they commonly exist in symbiosis with cnidarians. Attempts to culture them often retrieve isolates that may not be symbiotic, but instead exist as free‐living species. In particular, cultures of Symbiodinium clade E obtained from temperate environments were recently shown to feed phagotrophically on bacteria and microalgae. Genetic, behavioral, and morphological evidence indicate that strains of clade E obtained from the northwestern, southwestern, and northeastern temperate Pacific Ocean as well as the Mediterranean Sea constitute a single species: Symbiodinium voratum n. sp. Chloroplast ribosomal 23S and mitochondrial cytochrome b nucleotide sequences were the same for all isolates. The D1/D2 domains of nuclear ribosomal DNA were identical among Western Pacific strains, but single nucleotide substitutions differentiated isolates from California (USA) and Spain. Phylogenetic analyses demonstrated that S. voratum is well‐separated evolutionarily from other Symbiodinium spp. The motile, or mastigote, cells from different cultures were morphologically similar when observed using light, scanning, and transmission electron microscopy; and the first complete Kofoidian plate formula for a Symbiodinium sp. was characterized. As the largest of known Symbiodinium spp., the average coccoid cell diameters measured among cultured isolates ranged between 12.2 (± 0.2 SE) and 13.3 (± 0.2 SE) μm. Unique among species in the genus, a high proportion (approximately 10–20%) of cells remain motile in culture during the dark cycle. Although S. voratum occurs on surfaces of various substrates and is potentially common in the plankton of coastal areas, it may be incapable of forming stable mutualistic symbioses. 相似文献
97.
98.
Min Hyung Shin Hyung-Keun Ku Jin Sue Song Saehae Choi Se Young Son Hee-Dai Kim Sook-Kyung Kim Il Yeong Park Soo Jae Lee 《Journal of microbiology (Seoul, Korea)》2014,52(6):490-495
Prephenate dehydratase is a key enzyme of the biosynthesis of L-phenylalanine in the organisms that utilize shikimate pathway. Since this enzymatic pathway does not exist in mammals, prephenate dehydratase can provide a new drug targets for antibiotics or herbicide. Prephenate dehydratase is an allosteric enzyme regulated by its end product. The enzyme composed of two domains, catalytic PDT domain located near the N-terminal and regulatory ACT domain located near the C-terminal. The allosteric enzyme is suggested to have two different conformations. When the regulatory molecule, phenylalanine, is not bound to its ACT domain, the catalytic site of PDT domain maintain open (active) state conformation as Sa-PDT structure. And the open state of its catalytic site become closed (allosterically inhibited) state if the regulatory molecule is bound to its ACT domain as Ct-PDT structure. However, the X-ray structure of prephenate dehydratase from Streptococcus mutans (Sm-PDT) shows that the catalytic site of Sm-PDT has closed state conformation without phenylalanine molecule bound to its regulatory site. The structure suggests a possibility that the binding of phenylalanine in its regulatory site may not be the only prerequisite for the closed state conformation of Sm-PDT. 相似文献
99.
Rapid prototyping in tissue engineering: challenges and potential 总被引:14,自引:0,他引:14
Tissue engineering aims to produce patient-specific biological substitutes in an attempt to circumvent the limitations of existing clinical treatments for damaged tissue or organs. The main regenerative tissue engineering approach involves transplantation of cells onto scaffolds. The scaffold attempts to mimic the function of the natural extracellular matrix, providing a temporary template for the growth of target tissues. Scaffolds should have suitable architecture and strength to serve their intended function. This paper presents a comprehensive review of the fabrication methods, including conventional, mainly manual, techniques and advanced processing methods such as rapid prototyping (RP) techniques. The potential and challenges of scaffold-based technology are discussed from the perspective of RP technology. 相似文献
100.
An Appropriate Cutoff Value for Determining the Colonization of Helicobacter pylori by the Pyrosequencing Method: Comparison with Conventional Methods
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