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21.
Analysis of HL and O serotypes of Campylobacter strains by the flagellin gene typing system. 总被引:4,自引:1,他引:4
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We recently developed a molecular typing system for Campylobacter jejuni and Campylobacter coli based on restriction fragment length polymorphism analysis of the flagellin gene,flaA (I.Nachamkin, K. Bohachick, and C.M. Patton, J. Clin. Microbiol. 31:1531-1536, 1993). We extended the typing system to 83 flagellin types (designated flaA-1,flaA-2, etc.) on the basis of analysis of 404 isolates of C. jejuni and C. coli including common serotypes isolated in the United States, a selection of less common serotypes, and serotype reference strains. Of the 295 strains previously shown to belong to common HL and O serotypes (C. M. Patton, M.A. Nicholson, S.M. Ostroff, A.A. Ries, I.K. Wachsmuth, and R.V. Tauxe, J. Clin. Microbiol. 31:1525-1530, 1993), six flaA types accounted for 53.6% of strains as follows: flaA-1, 21.7%; flaA-7, 14.9%; flaA-27, 5.1%; flaA-49, 4.4%; flaA-13, 3.7%; and flaA-21, 3.7%. Seventy-five percent of the strains were within 15 flaA types, 90% were within 30 flaA types, and all 295 strains were contained within 52 flaA types. Within each HL or O serotype, there usually were multiple flaA types. For 12 common HL serotypes and 7 common O serotypes, more than 50% of these isolates were a single flaA type. A database was developed by using commercially available restriction fragment length polymorphism analysis software (ProRFLP; DNA ProScan, Inc., Nashville, Tenn.) that should allow other investigators to perform typing with this system. 相似文献
22.
Kwak Arim Kim Jae Hyun Choi Cheol Ung Kim In-Wha Oh Jung Mi Kim Kyungim 《International journal of clinical pharmacy》2019,41(2):460-469
International Journal of Clinical Pharmacy - Background While there is clear evidence for the benefit of statins in the secondary prevention of cardiovascular and cerebrovascular events, there is a... 相似文献
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Kyung Jin Nam Ki Seok Choo Ung Bae Jeon Tae Un Kim Jae-Yeon Hwang Jeong A Yeom Hee Seok Jeong Yoon Young Choi Jin You Kim Sang Hyup Lee Hyun Yul Kim Youn Joo Jung Young Hye Cho 《Japanese journal of radiology》2016,34(6):409-413
Purpose
We compared maximal diameters of ipsilateral (IMA) and contralateral (IMA) internal mammary arteries in patients with unilateral breast cancer and analyze the implications of enlargements of ipsilateral or contralateral IMAs in relation to histopathologic factors.Materials and methods
Of 568 women who underwent breast magnetic resonance imaging (MRI) examinations from January 2009 to May 2012, 196 had unilateral, histologically proven breast cancer. In 156 women, maximal IMA diameters in the second intercostal space were measured by two blinded radiologists in left and right sides using nonenhanced axial T2-weighted turbo spin-echo sequence images.Results
In the 156 study patients, mean maximal diameter of ipsilateral IMAs (2.37 ± 0.60 mm) was significantly larger than that of contralateral IMAs (2.03 ± 0.58 mm) (p = 0.00). Ipsilateral IMA enlargement was present in 66.7 % of the patients (104 of 156). Furthermore, ipsilateral IMA enlargement was found to be significantly associated with human epidermal growth factor receptor-2 (HER-2) expression (p = 0.039).Conclusions
Maximal IMA diameter was significantly greater in ipsilateral sides in breast cancer patients. Findings suggest ipsilateral IMA enlargement detected by MRI might be a useful additional predictor of HER-2 expression in unilateral breast cancer.25.
Computer prediction of allergen proteins from sequence-derived protein structural and physicochemical properties 总被引:1,自引:0,他引:1
BACKGROUND: Computational methods have been developed for predicting allergen proteins from sequence segments that show identity, homology, or motif match to a known allergen. These methods achieve good prediction accuracies, but are less effective for novel proteins with no similarity to any known allergen. METHODS: This work tests the feasibility of using a statistical learning method, support vector machines, as such a method. The prediction system is trained and tested by using 1005 allergen proteins from the Allergome database and 22,469 non-allergen proteins from 7871 Pfam families. RESULTS: Testing results by an independent set of 229 allergen and 6717 non-allergen proteins from 7871 Pfam families show that 93.0% and 99.9% of these are correctly predicted, which are comparable to the best results of other methods. Of the 18 novel allergen proteins non-homologous to any other proteins in the Swissprot database, 88.9% is correctly predicted. A further screening of 168,128 proteins in the Swissprot database finds that 2.9% of the proteins are predicted as allergen proteins, which is consistent with the estimated numbers from motif-based methods. CONCLUSIONS: Our study suggests that SVM is a potentially useful method for predicting allergen proteins and it has certain capability for predicting novel allergen proteins. Our software can be accessed at . 相似文献
26.
Neuronal plasticity has been traditionally associated with learning and memory processes in the hippocampal regions of the brain. It is now generally accepted that plasticity phenomena are also associated with other kinds of cellular changes and modifications occurring in all areas of the CNS after injury or intense neuronal activity. For instance, spinal cord injuries have been associated with a series of cellular modifications and adaptations taking place distally in sublesional areas. Some of these modifications include changes in the expression of immediate early genes (e.g., c-fos and nor-1), TNF-alpha, preprodynorphin, neurotrophic factors (e.g., BDNF and NT-3), and several subtypes of transmembranal receptors (e.g., 5-HT(1A) and 5-HT(2A)). This review constitutes an update of the current knowledge regarding this broadly defined plasticity phenomenon that occurs spontaneously or can be modulated by training in sublesional segments of the spinal cord. Spinal cord plasticity is an increasingly popular field of research, believed by many as being a complex phenomenon that may contribute to the development of innovative therapeutics and rehabilitative approaches for spinal cord injured patients. 相似文献
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28.
Akinori Kan Toshiyuki Ikeda Taku Saito Fumiko Yano Atushi Fukai Hironori Hojo Toru Ogasawara Naoshi Ogata Kozo Nakamura Ung‐Il Chung Hiroshi Kawaguchi 《Arthritis \u0026amp; Rheumatology》2009,60(11):3314-3323
Objective
To establish a cell culture system for noninvasive and real‐time monitoring of chondrogenic differentiation in order to screen for chondrogenic factors.Methods
The optimum reporter construct transfected into chondrogenic ATDC5 cells was selected by a luciferase reporter assay and fluorescence analysis during cultures with insulin. The established cell line was validated according to its fluorescence following stimulation with SOX proteins, bone morphogenetic protein 2 (BMP‐2), or transforming growth factor β (TGFβ) and was compared with the level of messenger RNA for COL2A1 as well as with the degree of Alcian blue staining. Screening of chondrogenic factors was performed by expression cloning using a retroviral expression library prepared from human tracheal cartilage. The expression pattern of the identified molecule was examined by in situ hybridization and immunohistochemistry. Functional analysis was performed by transfection of the identified gene, the small interfering RNA, and the mutated gene.Results
We established an ATDC5 cell line with 4 repeats of a highly conserved enhancer ligated to a COL2A1 basal promoter and the DsRed2 reporter (ATDC5‐C2ER). Fluorescence was induced under the stimulations with SOX proteins, BMP‐2, or TGFβ, showing good correspondence to the chondrogenic markers. Screening using the ATDC5‐C2ER system identified several chondrogenic factors, including sorting nexin 19 (SNX19). SNX19 was expressed in the limb cartilage of mouse embryos and in the degraded cartilage of adult mouse knee joints during osteoarthritis progression. The gain‐of‐function and loss‐of‐function analyses revealed a potent chondrogenic activity of SNX19.Conclusion
We established the ATDC5‐C2ER system for efficient monitoring of chondrogenic differentiation by fluorescence analysis, and we identified a novel chondrogenic factor (SNX19) using this system. This system will be useful for elucidating the molecular network of chondrogenic differentiation.29.
Background Sequentially evolving intracranial bilateral haematomas, where the second haematoma develops after the surgical removal of
the first one is rarely reported.
Aim To report a patient who developed an epidural haematoma after evacuation of a contralateral subdural haematoma.
Methods A 49-year-old male was admitted to our department after head injury. A brain computerized tomography (CT) scan revealed an
acute subdural haematoma in the right temporal area which was evacuated. During his stay in the intensive care unit, he was
submitted to intracranial pressure monitoring, which soon rose.
Results A new CT scan showed an acute epidural haematoma in the contralateral parietal area that was also evacuated.
Conclusions While rising intracranial pressure after the evacuation of a traumatic haematoma is usually attributed to brain oedema or
recurrent haematoma at the craniotomy site, the development of a contralateral epidural haematoma requiring surgical treatment
should not be overlooked. 相似文献
30.
Alleviation of capsular formations on silicone implants in rats using biomembrane-mimicking coatings
Ji Ung Park Jiyeon Ham Sukwha Kim Ji-Hun Seo Sang-Hyon Kim Seonju Lee Hye Jeong Min Sunghyun Choi Ra Mi Choi Heejin Kim Sohee Oh Ji An Hur Tae Hyun Choi Yan Lee 《Acta biomaterialia》2014,10(10):4217-4225
Despite their popular use in breast augmentation and reconstruction surgeries, the limited biocompatibility of silicone implants can induce severe side effects, including capsular contracture – an excessive foreign body reaction that forms a tight and hard fibrous capsule around the implant. This study examines the effects of using biomembrane-mimicking surface coatings to prevent capsular formations on silicone implants. The covalently attached biomembrane-mimicking polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), prevented nonspecific protein adsorption and fibroblast adhesion on the silicone surface. More importantly, in vivo capsule formations around PMPC-grafted silicone implants in rats were significantly thinner and exhibited lower collagen densities and more regular collagen alignments than bare silicone implants. The observed decrease in α-smooth muscle actin also supported the alleviation of capsular formations by the biomembrane-mimicking coating. Decreases in inflammation-related cells, myeloperoxidase and transforming growth factor-β resulted in reduced inflammation in the capsular tissue. The biomembrane-mimicking coatings used on these silicone implants demonstrate great potential for preventing capsular contracture and developing biocompatible materials for various biomedical applications. 相似文献