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41.
Abstract

We report here the case of a 48-year-old Japanese woman showing plaque-forming scattered indurative papules on her face, buttock and extremities. Histological examination revealed a large amount of interstitial mucin deposition, and negative direct immunofluorescence was observed. The provocative phototesting reproduced the skin lesion, and the patient was diagnosed with lupus erythematosus tumidus (LET). A review of ten LET cases previously reported in Japan revealed that all of these cases had clinicopathological features similar to those reported for European cases, although not all of the former fully satisfied the European criteria.  相似文献   
42.
The presence of antinuclear antibodies (ANAs), directed against intracellular antigens, is a hallmark of systemic autoimmune rheumatic diseases. The indirect immunofluorescence (IIF) assay is among the most commonly used routine methods for ANA detection as the screening test. The objective of the study was to evaluate ANA patterns in a 4‐year period retrospectively. All 19 996 serum samples that were sent to the Laboratory of Medical Microbiology of the tertiary Hospital by any hospital department between 1 January 2009 and 1 January 2013 with a request to test for ANA, anti‐ENA or both were included in the study. Of these samples, 4375 (21.9%) were ANA‐IIF‐positive and 15621 (78.1%) were ANA‐IIF‐negative. The presented ANA‐positive samples consisted of 2392 (54.67%) homogenous, 818 (18.70%) speckled, 396 (9.05%) centromere, 242 (5.53%) nucleolar, 213 (4.87%) nuclear dots, 178 (4.07%) cytoplasmic (except for actin and golgi), 24 (0.55%) actin, 9 (0.21%) golgi, 53 (1.21%) nuclear membrane and 50 (1.14%) mixed pattern. Totally 7800 samples were examined by LIA. Of these samples, 3440 were positive and 4307 were negative with IIF and LIA. In addition, 22 samples were detected as IIF‐positive but LIA‐negative, whereas the rest 31 samples were IIF‐negative but LIA‐positive. ANA patterns in 22 IIF‐positive samples were homogenous (9), speckled (5), golgi (4), cytoplasmic (3) and nucleolar (1). SSA/Ro‐52, SSB/La and Scl‐70 positivity were detected in 31 IIF‐negative/LIA‐positive samples by LIA. The present study comes forward with its overall scope, which covers 4‐year data obtained in tertiary hospital located in the western part of Turkey.  相似文献   
43.
《REV BRAS REUMATOL》2014,54(1):13-20
ObjectiveTo establish the abnormal title and the appropriate screening dilution for ANA (antinuclear antibodies) test by indirect immunofluorescence on HEp-2 cells (ANA HEp-2).MethodsAn analysis of ANA Hep-2 in serum samples from 126 healthy individuals was performed. The samples were screened at a dilution of 1:80, and those positive were di- luted to the title of 1:5120. The abnormal title of ANA was defined as that corresponding to the 95th percentile of the test in this population. The sensitivity of the different titles of antinuclear antibodies was determined in a group of 136 patients with a diagnosis of auto- immune rheumatic disease, and the specificity was determined in a group of 118 patients with other rheumatic diseases. The optimal cutoff value of the test was determined by ROC curve analysis.ResultsThe frequency of ANA positivity in healthy subjects was 13.2%. There was no dif- ference in the frequency of positive results according to gender or age. The abnormal title of ANA was defined as the dilution of 1:160. The 1:80 dilution had sensitivity of 87.7% and specificity of 67.8%, while the 1:160 dilution had sensitivity of 82% and specificity of 73.7%. By ROC curve analysis, a dilution of 1:160 corresponded to the optimal cutoff value.ConclusionThe abnormal title and the optimal cutoff value of ANA HEp-2 in the population was 1:160. Therefore, the dilution of 1:160 is the optimal screening dilution, with better specificity but without significantly compromising the sensitivity of the diagnostic test.  相似文献   
44.
45.
Reg family proteins such as Reg1 and islet neogenesis-associated protein (INGAP) have long been implicated in the growth and/or neogenesis of pancreatic islet cells. Recent reports further suggest similar roles to be played by new members such as Reg2, Reg3α, and Reg3β. We have studied their age-, isoform-, and tissue-specific expressions. RNA and protein were isolated from C57BL/6 mice aged 7, 30, and 90 days. Using real-time polymerase chain reaction, the levels of Reg gene expression in the pancreas were 20–600-fold higher than that in other tissues (?duodenum>stomach>liver); gene expression of Reg2, Reg3α, and Reg3β was age dependent as it was hardly detectable at day 7, increased drastically at day 30, and significantly decreased at day 90; the levels of pancreatic proteins displayed similar age-dependent variations. Using dual-labeled immunofluorescence, Reg2, Reg3α, and Reg3β were abundantly expressed in most acinar cells of the pancreas, in contrast to INGAP which exhibited stepwise increases from day 7 to day 90 and colocalized with the α-cells. These new Reg genes were mainly expressed in the pancreas, with clear age-dependent and isoform-specific patterns.  相似文献   
46.
47.
OBJECTIVE: To evaluate an immunofluorescence antibody test (IFAT) for diagnosis of schistosomiasis in nonimmune travellers and immigrants from endemic areas. METHODS: 65 patients (48 Danes and 17 immigrants) with schistosomiasis were included. The diagnosis of schistosomiasis was based on the presence of schistosome eggs in faeces, urine, sperm, rectal or bladder biopsies and/or the presence of specific antibodies determined by the serological immunofluorescence antibody test (IFAT). Egg excretion was detected using conventional methods and the IFAT performed on whole S. mansoni schistosomula worms, harvested after 8 weeks from mice. Two patterns of immunofluorescence were observed: Fluorescence in the gut of the schistosome called 'Gut Associated Antigen, GAA', and fluorescence of the surface of the schistosomula called 'Membrane Bound Antigen, MBA'. RESULTS: Eggs were found in 44% of the Danish patients and in 76% of immigrants. The diagnosis was based on a positive IFAT in 48% of the patients. In patients from nonendemic areas, the finding of antibodies against GAA was diagnostic while optimal sensitivity in the immigrants was reached by measuring antibodies against both GAA and MBA. CONCLUSION: In patients from nonendemic areas GAA is a sensitive marker of acute infection with schistosomiasis. In patients from endemic areas the demonstration of both GAA and MBA is necessary to properly identify long-lasting, nonacute infections. Egg-detection and/or measurement of CAA and CCA remain the methods of choice to monitor treatment as the immunofluorescence assay may remain positive for several years after treatment.  相似文献   
48.
《Vaccine》2015,33(45):6085-6092
The varicella-zoster virus (VZV) Oka vaccine strain (vOka) is highly efficient and causes few adverse events; therefore, it is used worldwide. We previously constructed recombinant vOka (rvOka) harboring the mumps virus gene. Immunizing guinea pigs with rvOka induced the production of neutralizing antibodies against the mumps virus and VZV.Here, we constructed recombinant vOka viruses containing either the respiratory syncytial virus (RSV) subgroup A fusion glycoprotein (RSV A–F) gene or RSV subgroup B fusion glycoprotein (RSV B–F) gene (rvOka-RSV A–F or rvOka-RSV B–F). Indirect immunofluorescence and Western blot analyses confirmed the expression of each recombinant RSV protein in virus-infected cells. Immunizing guinea pigs with rvOka-RSV A–F or rvOka-RSV B–F led to the induction of antibodies against RSV proteins. These results suggest that the current varicella vaccine genome can be used to generate custom-made vaccine vectors to develop the next generation of live vaccines.  相似文献   
49.
Apart from qualitative flags, that are typically inefficient and uninformative, haematology instruments provide little meaningful information about lymphocyte populations or the lineage of atypical or immature elements, The CELL‐DYN Sapphire haematology analyser uses integrated optical and fluorescence (488 nm) measurements, with FL1 (FITC) and FL2 (PE) detectors being configured for fluorescent analysis. As monoclonal antibodies (Mab) are widely used as cellular probes, and are likely to constitute the future basis for immunodifferentials, we explored the feasibility of implementing immunofluorescence on this routine haematology analyser. An extensive series of Mab (CD2, CD3, CD4, CD8, CD11b, CD13, CD14, CD16, CD19, CD22, CD33, CD34, CD41, CD42b, CD45, CD56, CD61, CD64, CD235a and HLA‐DR) were tested singly or in FITC/PE combinations. Analyser processing and data acquisition was achieved using CD‐Sapphire automated CD61 immunoplatelet or CD3/4/8 assay procedures and, apart from mixing EDTA‐blood and antibody, no further sample manipulation was required. Downloaded raw files were processed with cytometry software, and all evaluated reagents showed population discrimination analogous to flow cytometry. Practical procedures were straightforward and required minimal operator training. Extended information that can be obtained from monoclonal antibodies with a routine haematology analyser has the potential to extend haematology laboratory practices and positively impact laboratory and clinical efficiency.  相似文献   
50.
Summary Conventional detection of islet cell antibodies is based on indirect immunofluorescence performed on frozen human pancreas sections. The number and nature of epitopes recognized by antibodies detected by such techniques are unknown. To determine the existence of heterogeneous fluorescence patterns of islet cell antibodies on pancreatic sections, we selected two sera showing a distinctive granular fluorescence. We then tested random sera from patients with Type 1 (insulin-dependent) diabetes mellitus for their ability to block ultimate binding of fluorescein isothiocyanate-labelled immunoglobulins purified from these two sera with a characteristic granular pattern. Among 102 subjects with recent-onset Type 1 diabetes, 79 had detectable anti-islet cell antibodies; 21 showed complete blockade of the binding to islets of granular fluorescein isothiocyanate-labelled immunoglobulins. The majority of these 21 patients were women carrying a DR3 non-DR4 DQB1*0201 allele, with under-representation of DRB1*0402 and 0405. Discrimination between islet cell antigenic specificities may help in identifying islet cell autoantibodies in autoimmune Type 1 diabetes.  相似文献   
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