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81.
Chia-Ying Liu Chih-Cheng Lai Hsiu-Tzy Chiang Min-Chi Lu Ling-Fang Wang Tsai-Ling Tsai Mei-Yu Kang Yi-Ni Jan Yi-Ting Lo Wen-Chien Ko Shu-Hui Tseng Chun-Ming Lee Po-Ren Hsueh 《Journal of microbiology, immunology, and infection》2019,52(1):62-74
Background/purpose
This study investigated the distribution and persistence of multidrug resistant organisms (MDROs) including methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and multidrug-resistant Acinetobacter baumannii (MDRAB) in six long-term care facilities (LTCFs).Methods
We investigated the distribution of MDROs in residents of six LTCFs and their environments from January to December 2016 (intervention period). Active surveillance of colonization of MDROs was performed by culturing rectal and nasal swab samples from the residents every three months. Multilocus sequence typing (MLST) was conducted, and genes for panton-valentine leukocidin (PVL) from MRSA isolates were determined.Results
A total of 521 samples were positive for MDROs, and MRSA was the most common organism (65.1%), followed by MDRAB (11.3%), carbapenem-resistant Klebsiella pneumoniae (11.1%), carbapenem-resistant Escherichia coli (4.6%), and carbapenem-resistant P. aeruginosa (2.1%, n = 11). By a linear regression model, positive MRSA isolates from the environment were found to be statistically significant and associated with the number of colonized LTCF residents (p = 0.01), while the timing of the surveillance culture was not (p = 0.227). The main MLST types associated with PVL-production were sequence type (ST) 59, (40.0%, 24/60), ST30 (21.4%, 3/14), ST8 (87.5%, 14/16), and ST45 (3.6%, 1/28). The susceptibility rates of tetracycline (96.7%), trimethoprim-sulfamethoxazole (96.7%), and ciprofloxacin (81.7%) were statistically significant and higher in MRSA ST59, compared to the rates in MRSA ST45 isolates.Conclusions
MRSA was the most commonly colonized MDRO, both in the LTCF residents and in the environment, followed by MDRAB and carbapenem-resistant K. pneumoniae. 相似文献82.
Fine-needle aspiration (FNA) of the lymph node was done in five patients with histiocytic necrotizing lymphadenitis (Kikuchi's disease). In four patients, the aspirates were found to have many small and large atypical lymphocytes, some reactive, phagocytic histiocytes, and intense extracellular debris. Neutrophils, plasma cells, or multinucleated giant cells were not seen. These cytologic findings were considered diagnostic for Kikuchi's disease. In one patient, the aspirate did not show significant histiocytosis or tissue necrosis and was considered nondiagnostic. In patients with both typical clinical features and characteristic cytologic findings in the lymph node aspirates, FNA of the lymph node alone will suffice for diagnosis. In those patients with typical clinical features but nondiagnostic findings in the FNA aspirates, the diagnosis of Kikuchi's disease may have to be established either on repeated nodal FNA or on lymph node biopsy. 相似文献
83.
Ko AC Choo-Smith LP Hewko M Leonardi L Sowa MG Dong CC Williams P Cleghorn B 《Journal of biomedical optics》2005,10(3):031118
Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity. 相似文献
84.
Ko KS Kim JM Kim JW Jung BY Kim W Kim IJ Kook YH 《Journal of clinical microbiology》2003,41(7):2908-2914
Comparative sequence analysis was performed upon Bacillus anthracis and its closest relatives, B. cereus and B. thuringiensis. Portions of rpoB DNA from 10 strains of B. anthracis, 16 of B. cereus, 10 of B. thuringiensis, 1 of B. mycoides, and 1 of B. megaterium were amplified and sequenced. The determined rpoB sequences (318 bp) of the 10 B. anthracis strains, including five Korean isolates, were identical to those of Ames, Florida, Kruger B, and Western NA strains. Strains of the "B. cereus group" were separated into two subgroups, in which the B. anthracis strains formed a separate clade in the phylogenetic tree. However, B. cereus and B. thuringiensis could not be differentiated. Sequence analysis confirmed the five Korean isolates as B. anthracis. Based on the rpoB sequences determined in the present study, multiplex PCR generating either B. anthracis-specific amplicons (359 and 208 bp) or cap DNA (291 bp) in a virulence plasmid could be used for the rapid differential detection and identification of virulent B. anthracis. 相似文献
85.
Noninfectious Virus-Like Particle Antigen for Detection of Swine Vesicular Disease Virus Antibodies in Pigs by Enzyme-Linked Immunosorbent Assay
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Young-Joon Ko Kang-Seuk Choi Jin-Ju Nah David J. Paton Jae-Ku Oem Ginette Wilsden Shien-Young Kang Nam-In Jo Joo-Ho Lee Jae-Hong Kim Hee-Woo Lee Jong-Myeong Park 《Clinical and Vaccine Immunology : CVI》2005,12(8):922-929
An inactivated SVDV antigen is used in current enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies to swine vesicular disease virus (SVDV). To develop a noninfectious recombinant alternative, we produced SVDV-like particles (VLPs) morphologically and antigenically resembling authentic SVDV particles by using a dual baculovirus recombinant, which expresses simultaneously the P1 and 3CD protein genes of SVDV under different promoters. Antigenic differences between recombinant VLPs and SVDV particles were not statistically significant in results obtained with a 5B7-ELISA kit, indicating that the VLPs could be used in the place of SVDV antigen in ELISA kits. We developed a blocking ELISA using the VLPs and SVDV-specific neutralizing monoclonal antibody 3H10 (VLP-ELISA) for detection of SVDV serum antibodies in pigs. The VLP-ELISA showed a high specificity of 99.9% when tested with pig sera that are negative for SVDV neutralization (n = 1,041). When tested using sera (n = 186) collected periodically from pigs (n = 19) with experimental infection with each of three different strains of SVDV, the VLP-ELISA detected SVDV serum antibodies as early as 3 days postinfection and continued to detect the antibodies from all infected pigs until termination of the experiments (up to 121 days postinfection). This test performance was similar to that of the gold standard virus neutralization test and indicates that the VLP-ELISA is a highly specific and sensitive method for the detection of SVDV serum antibodies in pigs. This is the first report of the production and diagnostic application of recombinant VLPs of SVDV. Further potential uses of the VLPs are discussed. 相似文献
86.
Hepatic lectin blocking experiments with D-galactose in Balb/c mice showed that parenchymal liver cells are obviously not involved in Listeria monocytogenes infection (strain SLCC 4013, 5 × 106 cells i.v.). Using the bacterial immunomodifier Propionibacterium avidum KP-40 the importance of an activated mononuclear phagocyte system in the early stage of Listeria infection could be demonstrated.This study was supported by the Deutsche Forschungsgemeinschaft 相似文献
87.
The IgG subclasses of immunoglobulin for intravenous injection (IVIg) were investigated after various different types of treatment.
The level of IgG2 was relatively low in preparations treated with pepsin, but by changing the clone producing anti-IgG2 antibody,
the level approached that of normal human serum. Though undetectable in sulfonated immunoglobulin preparations, IgG3 was detected
after reoxidation. When determining the IgG subclasses of IVIg, it must be kept in mind that the apparent value may subsequently
become lower due to the depressed reaction of the antibody. 相似文献
88.
Detection of highly pathogenic and low pathogenic avian influenza subtype H5 (Eurasian lineage) using NASBA 总被引:15,自引:0,他引:15
Nucleic acid sequence-based amplification (NASBA) is a technique that allows the rapid amplification of specific regions of nucleic acid obtained from a diverse range of sources. It is especially suitable for amplifying RNA sequences. A NASBA technique has been developed that allows the detection of avian influenza A subtype H5 from allantoic fluid harvested from inoculated chick embryos. The amplified viral RNA is detected by electrochemiluminescence. The NASBA technique described below is rapid and specific for the identification of influenza A subtype H5 viruses of the Eurasian lineage. More importantly, it can be used to distinguish highly pathogenic and low pathogenic strains of the H5 subtype. 相似文献
89.
The clinicopathologic and immunohistochemical finding of 10 cases of nasal non-Hodgkin's lymphoma (NHL) and 23 cases of Waldeyer's ring NHL were studied. Immunohistochemically, nasal NHL expressed T-cell markers exclusively, whereas the NHL of Waldeyer's ring were of both T-cell (56.5%) and B-cell lineages (43.5%). Angioinvasiveness by tumor cells was exclusively noted in the T-lineage lymphomas. Epithelial hyperplasia, epitheliotropism by tumor cells, and extensive invasion of adjacent normal tissue were more prominent in T-cell lymphomas than in B-cell lymphomas. T-lineage lymphomas showed distant extranodal spread pattern involving the skin, soft tissue, stomach, spleen, and the liver, whereas B-lineage lymphomas tended to localize in the lymph nodes. The survival rate of Nasal NHL was similar to that of Waldeyer's ring NHL. Although not statistically significant because of small sample numbers, immunophenotype, histologic groups of monomorphic lymphoma, and stage had prognostic importance. In general, T-lineage lymphomas presented with a higher stage than B-lineage lymphomas (p < 0.05)-and overall survival was poor. Stage I disease showed a much more favorable prognosis than stage II disease. Monomorphic lymphomas had a shorter survival than polymorphic reticulosis (PR) or lymphomas with features of PR. This result in conjunction with the morphologic transition between them suggested that monomorphic lymphoma may represent the most advanced stage in the spectrum of PR, lymphoma with features of PR, and monomorphic lymphoma. 相似文献
90.
Hematopoietic neoplasm coexpressing CD4 and CD56 includes a subset of acute myeloid leukemia with myelomonocytic differentiation, plasmacytoid monocyte tumor, and other immature hematopoietic neoplasms of undefined origin. Herein, we report a CD4+CD56+CD68+ hematopoietic tumor that was thought to be a tumor of plasmacytoid monocytes. This case is unique in the absence of accompanying myelomonocytic leukemia and the faint expression of cCD3 on the tumor cells. The patient was a 22-yr old man presented with multiple lymphadenopathy and an involvement of the bone marrow. Tumor cells were large and monomorphic with an angulated eosinophilic cytoplasm of moderate amount. Nuclei of most tumor cells were eccentric and round with one or two prominent nucleoli. Rough endoplasmic reticulum was prominent in electron microscopic examination. Tumor cells expressed CD4, CD7, CD10, CD45RB, CD56, CD68, and HLA-DR and were negative for CD1a, CD2, sCD3, CD5, CD13, CD14, CD20, CD33, CD34, CD43, CD45RA, TIA-1, S-100, and TdT. cCD3 was not detected in the immunostaining using paraffin tissue, but was faintly expressed in flow cytometry and immunostaining using a touch imprint slide. T-cell receptor gene rearrangement analysis and EBV in situ hybridization showed negative results. Cytochemically, myeloperoxidase, Sudan black B, and alpha naphthyl butyrate esterase were all negative. 相似文献