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21.
Negative conversion of antimitochondrial antibody in primary biliary cirrhosis: a case of autoimmune cholangitis 总被引:3,自引:0,他引:3
Cho YJ Han DS Kim TY Jang SJ Jeon YC Sohn JH Lee IH Park KN 《Journal of Korean medical science》1999,14(1):102-106
Autoimmune cholangitis is a clinical constellation of chronic cholestasis, histological changes of chronic nonsuppurative cholangitis and the presence of autoantibodies other than antimitochondrial antibody (AMA). It is uncertain whether this entity is definitely different from AMA positive primary biliary cirrhosis (PBC), though it shows some differences. We report a case of autoimmune cholangitis in a 59-year-old woman, who had been previously diagnosed as AMA-positive PBC associated with rheumatoid arthritis, has been converted to an AMA-negative and anticentromere antibody-positive PBC during follow-up. The response to ursodeoxycholic acid treatment is poor except within the first few months, but prednisolone was dropping the biochemical laboratory data. 相似文献
22.
Shobana Sekar Livia Tomasini Christos Proukakis Taejeong Bae Logan Manlove Yeongjun Jang Soraya Scuderi Bo Zhou Maria Kalyva Anahita Amiri Jessica Mariani Fritz J. Sedlazeck Alexander E. Urban Flora M. Vaccarino Alexej Abyzov 《Genome research》2020,30(12):1695
Somatic mosaicism, manifesting as single nucleotide variants (SNVs), mobile element insertions, and structural changes in the DNA, is a common phenomenon in human brain cells, with potential functional consequences. Using a clonal approach, we previously detected 200–400 mosaic SNVs per cell in three human fetal brains (15–21 wk postconception). However, structural variation in the human fetal brain has not yet been investigated. Here, we discover and validate four mosaic structural variants (SVs) in the same brains and resolve their precise breakpoints. The SVs were of kilobase scale and complex, consisting of deletion(s) and rearranged genomic fragments, which sometimes originated from different chromosomes. Sequences at the breakpoints of these rearrangements had microhomologies, suggesting their origin from replication errors. One SV was found in two clones, and we timed its origin to ∼14 wk postconception. No large scale mosaic copy number variants (CNVs) were detectable in normal fetal human brains, suggesting that previously reported megabase-scale CNVs in neurons arise at later stages of development. By reanalysis of public single nuclei data from adult brain neurons, we detected an extrachromosomal circular DNA event. Our study reveals the existence of mosaic SVs in the developing human brain, likely arising from cell proliferation during mid-neurogenesis. Although relatively rare compared to SNVs and present in ∼10% of neurons, SVs in developing human brain affect a comparable number of bases in the genome (∼6200 vs. ∼4000 bp), implying that they may have similar functional consequences.Somatic mosaicism, the presence of more than one genotype in the somatic cells of an individual, is a prominent phenomenon in the human central nervous system. Forms of mosaicism include aneuploidies and smaller copy number variants (CNVs), structural variants (SVs), mobile element insertions, indels, and single nucleotide variants (SNVs). The developing human brain exhibits high levels of aneuploidy compared to other tissues, generating genetic diversity in neurons (Pack et al. 2005; Yurov et al. 2007; Bushman and Chun 2013). Such aneuploidy was suggested to be a natural feature of neurons, rather than a distinctive feature of neurodegeneration. However, the frequency of aneuploidy in neurons has been debated, with a separate study suggesting that aneuploidies occur in only about 2.2% of mature adult neurons (Knouse et al. 2014). They hence infer that such aneuploidy could have adverse effects at the cellular and organismal levels. Additionally, analysis of single cells from normal and pathological human brains identified large, private, and likely clonal somatic CNVs in both normal and diseased brains (Gole et al. 2013; McConnell et al. 2013; Cai et al. 2014; Knouse et al. 2016; Chronister et al. 2019; Perez-Rodriguez et al. 2019), with 3%–25% of human cerebral cortical nuclei carrying megabase-scale CNVs (Chronister et al. 2019) and deletions being twice as common as duplications (McConnell et al. 2013). Given that CNVs often arise from nonhomologous recombination and replication errors, their likely time of origin is during brain development. However, when CNVs first arise in human brain development has not yet been investigated. The present work is the first to examine this question using clonal populations of neuronal progenitor cells (NPCs) obtained from fetal human brains.Detection of CNVs in single neurons is challenging, given the need to amplify DNA. Such amplification may introduce artifacts that could, in turn, be misinterpreted as CNVs. In order to address this technical limitation, Hazen et al. reprogrammed adult postmitotic neurons using somatic cell nuclear transfer (SCNT) of neuronal nuclei into enucleated oocytes (Hazen et al. 2016). These oocytes then made sufficient copies of the neuronal genome allowing for whole-genome sequencing (WGS), thus eliminating the need for amplification in vitro. Using this method, they identified a total of nine structural variants in six neurons from mice, three of which were complex rearrangements. However, it is not possible to extend such studies to humans, given the ethical issues involved, besides the technical challenges in obtaining and cloning adult neurons. To circumvent the need of single-cell DNA amplification or nuclear cloning, we examined clonal cell populations obtained from neural progenitor cells from the frontal region of the cerebral cortex (FR), parietal cortex (PA) and basal ganglia (BG) and describe here the discovery and analysis of mosaic SVs in these NPCs (Bae et al. 2018). These clones were sequenced at 30× coverage (much higher than most previous single-cell studies), allowing identification of SVs other than large deletions and duplications as well as precise breakpoint resolution. 相似文献
23.
The immunity of a combined DNA vaccine of HSV-2 glycoproteins B2 (gB2) and D2 (gD2) genes in comparison to individual vaccines was studied with regard to protecting against the HSV infection. Two recombinant DNA vaccines of the pHS2-gB2 or pHS2-gD2 were constructed and formulated. The neutralizing antibody titers appeared higher in the B2:D2 gene cocktail-vaccinated mice than that of the individual B2 or D2 gene-vaccinated group alone, and the positive KOS control induced higher titer of the neutralizing antibody than combined or individual gene vaccines. The mock-immunized mice failed to induce enough. The ranks for the CTL activity and the protection rates against the lethal intravaginal challenge were shown as KOS>B2:D2 cocktail>D2>B2 gene vaccines. The vaginal external diseases in the B2:D2 or D-vaccinated mice were significantly reduced against the challenging dosages. The virus titers in the vaginal secretions of the vaccinated mice significantly reduced with time, and the B2:D2 gene vaccine decreased more than each individual vaccine alone. It can be concluded that the cocktailed vaccines are more effective in the humoral and cellular immune responses in the mice, and in the protection of the mice against the intravaginal challenging dosages when compared with individual gene vaccines. All the DNA vaccines failed to block the latent infection in sensory nerves. 相似文献
24.
Increased expression of glucose transporter1 (GLUT1) has been reported in many human cancers. We hypothesized that the degree of GLUT1 might provide a useful biological information in gastric adenocarcinoma. RT-PCR and immunostaining were used to analyze GLUT1 expression in gastric cancer. RT-PCR showed GLUT1 expression was not largely detected in normal gastric tissue but was detected in cancerous gastric tissue of counterpart. By immunohistochemistry, GLUT1 protein was absent in normal gastric epithelium and intestinal metaplasia. 11 of 65 patients with gastric adenocarcinoma had specific GLUT1 immunostaining in a plasma membrane pattern with varied intensities. GLUT1 protein did not show any significant correlation with tumor stage and nodal metastasis (p>0.05 by Mann-Whitney test). However, the positive immunostaining for GLUT1 is associated with intestinal differentiation (p=0.003). Our results suggest that GLUT1 protein is associated with intestinal type of gastric cancer. 相似文献
25.
Two cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice 总被引:2,自引:0,他引:2
Cho HG Min HY Jang DS Shin YW Kwon KS Kim YS Kim MY Kim KR 《Yonsei medical journal》2000,41(4):522-527
We recently treated two cases of chronic pancreatitis with obstructive jaundice due to compression of the common bile duct by pancreatic pseudocyst. The two cases were males admitted with the complaint of icteric skin color. The first, a 46-year-old male, admitted with the complaint of icteric skin color. He was treated by operative cystojejunostomy after percutaneous drainage of the pseudocyst and percutaneous transhepatic biliary drainage. The other case was a 58 year-old male who admitted with the complaint of icteric skin color. He had an infected pseudocyst in the pancreas and was endoscopically treated. Both of them were discharged with favorable clinical course and normal laboratory findings after the treatment. The former patient remained well 11 months after treatment, but the latter patient died from necrotizing pancreatitis and septic shock 6 months after treatment. Most cases of obstructive jaundice associated with pseudocysts appear to be due to fibrotic stricture of the intrapancreatic portion of the common bile duct rather than due to compression of the bile duct by the pseudocyst. In a patient with secondary pancreatic infection or obstructive jaundice following pancreatic disease, differentiating between these two conditions is an important aspect of accurate diagnosis and therapy. Herein we report two unusual cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice. 相似文献
26.
Evaluation of an Immunoglobulin M Capture Enzyme-Linked Immunosorbent Assay for Diagnosis of Orientia tsutsugamushi Infection
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Won-Jong Jang Myung-Suk Huh Kyung-Hee Park Myung-Sik Choi Ik-Sang Kim 《Clinical and Vaccine Immunology : CVI》2003,10(3):394-398
To differentiate scrub typhus from other acute febrile diseases, a rapid and reliable serological diagnosis is important. We developed an immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (ELISA) for diagnosis of recent Orientia tsutsugamushi infections in humans. The 56-kDa major outer membrane protein of O. tsutsugamushi is well known as the most immunodominant antigen in scrub typhus. The test is based on the use of the biotinylated recombinant 56-kDa protein of O. tsutsugamushi Boryong, Bor56, which was expressed as a fusion protein with a maltose-binding protein in Escherichia coli. In the test, the serum IgM antibodies were captured by anti-human IgM antibodies coated onto a microtiter plate. The captured IgM antibodies were revealed through sequential addition of biotinylated Bor56 antigen and peroxidase-conjugated streptavidin to the plate. The IgM capture ELISA was compared with the immunofluorescence antibody assay (IFA) by testing 176 serum samples from patients with diagnosed cases of rickettsial disease and patients with other acute febrile diseases. Of the 81 IgG IFA-positive samples, 78 tested positive (sensitivity, 96.3%) and all 31 IgM IFA-positive samples tested positive (sensitivity, 100%) by the IgM capture ELISA. The specificity of the IgM capture ELISA was 99%, and 1 of the 95 IFA-negative samples was positive in the assay. These results strongly suggest that IgM capture ELISA using the recombinant Bor56 antigen is a reliable and detailed method for the detection of early O. tsutsugamushi infection. 相似文献
27.
Oh S Yoon YW Jang GJ Ahn JB Hong Gp Gang Gh Gang MS Hong Yu Gee JH 《Journal of Korean medical science》2003,18(4):589-591
We report a case of ruptured mycotic aneurysm involving innominate artery requiring an urgent surgical treatment. A 62-yr-old woman presented with fever and dyspnea. Previously, she was diagnosed with colon cancer and received right hemicolectomy and one cycle of adjuvant chemotherapy. On echocardiogram, pericardial effusion was noted and emergency pericardiocentesis was performed. CT scan revealed aortic aneurysm involving ascending aorta and innominate artery, and thrombi surrounding those structures. Patch repair of the defect in the ascending aorta and ringed Goretex graft to bypass the innominate and ascending aorta were performed. We believe that this is the first case of ruptured mycotic aneurysm involving innominate artery. 相似文献
28.
Detection and genotyping of Mycobacterium species from clinical isolates and specimens by oligonucleotide array 总被引:3,自引:0,他引:3
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Park H Jang H Song E Chang CL Lee M Jeong S Park J Kang B Kim C 《Journal of clinical microbiology》2005,43(4):1782-1788
Identification of pathogenic Mycobacterium species is important for a successful diagnosis of mycobacteriosis. The purpose of this study was to develop an oligonucleotide array which could detect and differentiate mycobacteria to the species level by using the internal transcribed spacer (ITS) sequence. Using a genus-specific probe and 20 species-specific probes including two M. avium-intracellulare complex (MAC)-specific probes, we have developed an ITS-based oligonucleotide array for the rapid and reliable detection and discrimination of M. tuberculosis, MAC, M. fortuitum, M. chelonae, M. abscessus, M. kansasii, M. gordonae, M. scrofulaceum, M. szulgai, M. vaccae, M. xenopi, M. terrae, M. flavescens, M. smegmatis, M. malmoense, M. simiae, M. marinum, M. ulcerans, M. gastri, and M. leprae. All mycobacteria were hybridized with a genus-specific probe (PAN-03) for detection of the genus Mycobacterium. Mycobacterial species were expected to show a unique hybridization pattern with species-specific probes, except for M. marinum and M. ulcerans, which were not differentiated by ITS-based probe. Among the species-specific probes, two kinds of species-specific probes were designed for MAC in which there were many subspecies. The performance of the oligonucleotide array assay was demonstrated by using 46 reference strains, 149 clinical isolates, and 155 clinical specimens. The complete procedure (DNA extraction, PCR, DNA hybridization, and scanning) was carried out in 4.5 h. Our results indicated that the oligonucleotide array is useful for the identification and discrimination of mycobacteria from clinical isolates and specimens in an ordinary clinical laboratory. 相似文献
29.
Jiunn Rong Chen Shih Yi Lee Bing Heng Yang Jang Jih Lu 《Journal of microbiology, immunology, and infection》2008,41(3):259-264
BACKGROUND AND PURPOSE: In order to reduce the turnaround time for laboratory diagnosis of bacteremia, the efficacy of identification and antimicrobial susceptibility testing using samples taken directly from positive BacT/ALERT(R) standard aerobic and standard anaerobic blood culture bottles was evaluated. METHODS: 160 positive blood culture bottles were examined and incubated at 35 degrees C in 5% carbon dioxide for 4-24 h, and an aliquot of the culture fluid was Gram stained. Samples containing Gram-negative bacilli were inoculated on VITEK(R) 2 ID-GNB (identification-Gram-negative bacilli) and AST (antimicrobial susceptibility testing)-GN04 cards, and those containing Gram-positive cocci were inoculated on ID-GPC (identification-Gram-positive cocci) and AST-P526 cards. The same samples were also examined by the standard method, involving subculture from positive BacT/ALERT standard blood culture bottles. RESULTS: Eighty seven of 97 Gram-negative bacilli (89.7%) and 21 of 63 Gram-positive cocci (33.3%) were correctly identified to the species level. For antimicrobial susceptibility testing, the direct method had an overall error rate of 5.4% for Gram-negative bacilli, with 0.9% very major, 0.9% major, and 3.6% minor discrepancies compared to the standard method. The overall error rate in antimicrobial susceptibility testing for the 13 Staphylococcus spp. was 10.3%, with 6.0% very major, 2.6% major, and 1.7% minor discrepancies. CONCLUSION: These data suggest that VITEK 2 cards inoculated with samples taken directly from positive Bact/ALERT blood culture bottles would provide acceptable identification and antimicrobial susceptibility testing results for Gram-negative bacilli, but not for Gram-positive cocci. Compared to the standard method, the direct method would reduce turnaround time by at least 24 h. 相似文献
30.
M M Floyd L S Guthertz V A Silcox P S Duffey Y Jang E P Desmond J T Crawford W R Butler 《Journal of clinical microbiology》1996,34(12):2963-2967
Polyphasic taxonomic methods were employed to characterize a new species of slowly growing, nonpigmented mycobacteria. We propose the name Mycobacterium triplex sp. nov. for this new taxon. Conventional identification testing demonstrated a group of similar organisms that were geographically widespread in the United States. Commercially available nucleic-acid probes specific for the Mycobacterium avium complex were unreactive for these strains. High-performance liquid chromatography analysis of the mycolic acids revealed mycolate profiles that closely resembled Mycobacterium simiae. Comparative 16S rRNA sequence data confirmed the phylogenetic relationship of the strains with the slowly growing mycobacteria. Representative-type strains have been deposited in the American Type Culture Collection as strain ATCC 700071 [corrected]. 相似文献