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OBJECTIVE: To determine the expression of tumour necrosis factor alpha (TNF alpha) and its soluble receptors (p55 and p75) in the sera and synovial fluid of patients with juvenile chronic arthritis (JCA), and their correlation with disease activity parameters. METHODS: Ninety eight sera from 45 patients with JCA (14 systemic, 12 polyarticular, 19 pauciarticular), 20 sera from age matched healthy controls, and five synovial fluids from five antinuclear antibody (ANA) positive pauciarticular JCA patients were tested for the presence of TNF alpha, soluble TNF receptors p55 and p75 (sTNFRp55, sTNFRp75), and interleukin-6 (IL-6) by an enzyme amplified sensitivity immunoassay. Physician global estimate of disease activity, weekly fever score and joint score, C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and haemoglobin concentration were evaluated as parameters of disease activity. The expression of p55 and p75 on peripheral mononuclear cells (MNCs) from five patients with systemic JCA and synovial MNCs from five ANA positive patients with pauciarticular JCA was evaluated by flow cytometry. RESULTS: TNF alpha serum concentrations did not differ significantly between the patients with active JCA and the control group. No correlation was found between TNF alpha and parameters of disease activity, but both p55 and p75 showed a significant positive correlation with the physician global estimate of disease activity (p < 0.001), ESR (p < 0.001), CRP (p < 0.001), and serum concentrations of IL-6 (p < 0.001). Serum concentrations of haemoglobin correlated inversely with the concentrations of p55 and p75 (p < 0.001). Synovial lymphocytes selectively expressed the p75 surface receptor. CONCLUSIONS: sTNFRp55 and sTNFRp75 each represent a sensitive marker of disease activity in JCA. Their increased expression in biological fluids may support the hypothesis that TNF alpha has a role in the pathogenesis of JCA.  相似文献   
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OBJECTIVE: Conservative treatment in vestibular schwannomas is mainly dependent on optimal tumor size determination. The first objective of this study was to establish interobserver and intraobserver variability and the accuracy and reproducibility of three different measurement methods: one bidimensional and two volumetrical. The second objective was to evaluate the influence of the use of different magnetic resonance imaging (MRI) slice thickness and the influence of patient's repositioning on the measurements' outcome. STUDY DESIGN: Two consecutive studies have been prospectively performed, both mainly concerning volumetrical measurements. SETTING: Both studies were performed in a tertiary academic, multidisciplinary center. PATIENTS: In the first study, 19 patients were included between March 1996 and May 2002, with a total of 52 scans. The second study comprised 14 patients. All patients in the first study had at least two MRI examinations performed according to a standard protocol (T1-weighted gadolinium-enhanced, slice thickness of 3 mm, and interslice gap of 0.3 mm). The population in the second study underwent a conservative wait and scan (W&S) treatment. METHODS: Both studies are discussed separately. In the first study, all scans were measured by four investigators, two of whom performed the measurements twice using three different methods. The first method concerns a manually performed bidimensional surface measurement along the petrous pyramid. The second method concerns a semiautomatic volumetrical measurement on a computer, relying on contour detection, and the last method concerns a fully automatic volume reconstruction also performed on a computer using different gray shade scales.All 14 patients included in the second study underwent three magnetic examinations. Three different T1-weighted gadolinium-enhanced sequences were used: the first using a slice thickness of 1 mm, the second again with 1-mm slice thickness but after having repositioned the patient. In the third sequence, a slice thickness of 3 mm was used. All scans were measured by two investigators using the three different methods, as described previously. RESULTS: The manual surface method shows large intraobserver variability, and its reproducibility is significantly lower compared with volume measurements. Because of a relatively large systematic error in small tumors, sensitivity of growth detection is low. Both volumetrical methods are hardly interobserver- and intraobserver-dependent, and the gray shade method turned out to be the most accurate. Radiologic progression is only significant at a volume increase of at least 50%. The influence of patient repositioning is negligible, whereas the use of 1-mm slice thickness seems to be superior to a 3-mm slice thickness. CONCLUSION: The volumetrical gray shade method is the most accurate method to detect early tumor progression. As tumor increase of at least 50% is needed to be able to speak of statistically significant tumor growth, the absence of radiologic progression does not mean that there is no tumor growth. Repositioning of the patient has no influence on the measurements' outcome, whereas for optimal magnetic resonance imaging examinations, a 1-mm slice thickness protocol seems to be superior.  相似文献   
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Patients with Taylor-type focal cortical dysplasia (TTFCD) generally present with medically intractable epilepsy and impaired neurological and/or intellectual functioning. Surgery usually proves to be the only treatment approach leading to control of seizures. We describe a 17-year-old girl with TTFCD who exhibited a very long period of seizure remission. Combined clinical and neuroimaging findings were compatible with a diagnosis of a balloon cell-subtype TTFCD. As for the clinical course, partial motor seizures began at one year of age and ceased at five: our patient has had no seizure recurrence over a 12-year-follow-up. Moreover, throughout the 15-year follow-up, neurological examinations and cognitive abilities always remained within normal limits. Neuropsychological assessment clearly showed no impairments in executive functions: planning abilities, working memory, attention and impulse control, or constructive aspects of motor coordination. The predominant deficits pertained to verbal abilities in the context of borderline intellectual performances. To our knowledge, this case report documents the longest duration of seizure remission in a patient with TTFCD, thus emphasizing the possible benign course of such dysplastic lesions which usually have a poor prognosis, leading to early surgical treatment.  相似文献   
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Detection of atypical megakaryocytes in bone marrow biopsies, especially in cases of myelodysplastic syndromes (MDS), chronic myeloproliferative disorders (CMPD) and acute leukemias, is facilitated by staining for markers such as Ulex europaeus agglutinin (UEA)-J, CD31, CD61 and von Willebrand factor (VWF), the latter being considered the most sensitive. Recently, LAT (linker for activation of T cells), a molecule involved in T-cell activation and platelet aggregation, was found to be expressed by megakaryocytes and platelets in tissue sections. We compared VWF and LAT immunoreactivity on megakaryocytes in 64 bone marrow biopsies from 12 normal controls (NC), and from patients with MDS (n=18), CMPD (n=21) and acute megakaryocytic leukemia (AML-M7, n=13). Immunostaining was performed on paraffin sections with polyclonal antibodies against VWF and LAT. Immunoreactivity was evaluated by counting positive megakaryocytes in 10 high-power fields, and values were compared using Student's t test for paired data. Both VWF and LAT predominantly stained the cytoplasm of megakaryocytes, although LAT was also recognizable on the cell membrane. In most biopsies, the immunoreactivity of the two antibodies was quite similar. No significant differences were noticed between the mean values of VWF+ and LAT+ megakaryocytes. However, in 22 cases (5 NC; 5 MDS; 6 CMPD; 6 AML-M7), the number of LAT+ megakaryocytes was at least 30% higher than VWF+cells, while in 3 cases opposite findings were found. In 3 AML-M7 cases, anti-LAT antibodies stained numerous megakaryocytes, but anti-VWF staining was practically negative; in another 5 AML-M7 cases, anti-LAT labeling was much stronger than anti-VWF staining. LAT represents a useful immunohistochemical marker for megakaryocytes in normal and pathological conditions. It seems to be expressed by megakaryocytes more than VWF in most cases and, particularly, in conditions associated with poorly differentiated megakaryocytes, such as acute megakaryocytic leukemias. The use of LAT staining should be recommended in association with other megakaryocyte markers in the study of bone marrow biopsies in cases of hematopoietic disorders.  相似文献   
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So-called plasmacytoid T cells represent a subset of monocyte related cells, which share with endothelium the CD36+CD11b (OKM5+OKM1) phenotype. The reactivity of plasmacytoid T cells with rat monoclonal antibody HECA-452, highly specific for high endothelial venules, was analyzed in reactive lymph nodes. In all cases, HECA-452 not only labelled the endothelium of high endothelial venules, but also strongly reacted with singular and clustered plasmacytoid T cells. The HECA-452 positivity for high endothelial venules and plasmacytoid T cells visualized a lymph node compartment extending from the subcapsular sinus to the corticomedullary junction. This compartment surrounded the composite nodule and was designated the ”extranodular“ compartment. The cooccurrence of plasmacytoid T cells and high endothelial venules in this extranodular compartment, together with their immunophenotypical similarities, may be indicative of functional co-operations.  相似文献   
7.
We evaluated the expression of T cell-restricted intracellular antigen (Tia-1), granzyme B, and perforin by lymphocytes and the degree of epithelial apoptosis in oral and cutaneous lichen planus (LP) in 51 untreated cases, including 27 oral LP (OLP) and 24 cutaneous LP (CLP) cases. The number of total dermal-positive lymphocytes in OLP and CLP was similar, indicating similar activity of the inflammatory process. Intraepithelial Tia-1-positive, perforin-positive, and granzyme B-positive lymphoid cells were more numerous in OLP than in CLP (P < .05). The epithelial cell apoptotic index (AI) was increased significantly in OLP (P < .05), particularly in erosive-atrophic variants. A linear correlation between AI and the mean +/- SEM number of intraepithelial and dermal perforin+ cells (6.85 +/- 2.44 and 27.48 +/- 10.19, respectively), per 10 high-power fields for OLP and for CLP (1.17 +/- 0.88 and 10.42 +/- 5.74, respectively), was found (intraepithelial, r = 0.50; dermal, r = 0.51; P < .01). These data suggest a pivotal role for perforin in triggering epithelial cell apoptosis. The differences of infiltrating cytotoxic cells and related AI observed in OLP and CLP are in keeping with the clinical behaviors that distinguish these LP variants.  相似文献   
8.
Within the GEN-COVID Multicenter Study, biospecimens from more than 1000 SARS-CoV-2 positive individuals have thus far been collected in the GEN-COVID Biobank (GCB). Sample types include whole blood, plasma, serum, leukocytes, and DNA. The GCB links samples to detailed clinical data available in the GEN-COVID Patient Registry (GCPR). It includes hospitalized patients (74.25%), broken down into intubated, treated by CPAP-biPAP, treated with O2 supplementation, and without respiratory support (9.5%, 18.4%, 31.55% and 14.8, respectively); and non-hospitalized subjects (25.75%), either pauci- or asymptomatic. More than 150 clinical patient-level data fields have been collected and binarized for further statistics according to the organs/systems primarily affected by COVID-19: heart, liver, pancreas, kidney, chemosensors, innate or adaptive immunity, and clotting system. Hierarchical clustering analysis identified five main clinical categories: (1) severe multisystemic failure with either thromboembolic or pancreatic variant; (2) cytokine storm type, either severe with liver involvement or moderate; (3) moderate heart type, either with or without liver damage; (4) moderate multisystemic involvement, either with or without liver damage; (5) mild, either with or without hyposmia. GCB and GCPR are further linked to the GCGDR, which includes data from whole-exome sequencing and high-density SNP genotyping. The data are available for sharing through the Network for Italian Genomes, found within the COVID-19 dedicated section. The study objective is to systematize this comprehensive data collection and begin identifying multi-organ involvement in COVID-19, defining genetic parameters for infection susceptibility within the population, and mapping genetically COVID-19 severity and clinical complexity among patients.Subject terms: Genetics research, Viral infection  相似文献   
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We describe the identification of a variant of the "Rome clone" of methicillin-resistant Staphylococcus aureus (MRSA), responsible for an outbreak involving 5 patients in a Cardiac Surgery Intensive Care Unit (CS-ICU) of a tertiary-care University Hospital in Rome. All strains isolated from patients and from nasal swabs obtained from four members of the CS-ICU personnel, belonged to the same identified clone. The characteristics of this clone were: (1) resistance to ampicillin, oxacillin, gentamicin, ciprofloxacin, erythromycin, clindamycin, rifampin, spectinomycin, and tetracycline; (2) vancomycin and teicoplanin MICs respectively of 2 and 4 mg/L; (3) heteroresistant subpopulations in the presence of 4 and 6 mg/L of vancomycin (10(-3) and 10(-5), respectively); (4) clonal type I::J::C determined following an established protocol (mec A::Tn 554 ::PFGE); (5) sequence type ST247 (3-3-1-12-4-4-16), obtained by multilocus sequence typing (MLST); and (6) the staphylococcal cassette chromosome mec (SCC) IA, obtained by multiplex PCR method. This new strain had different characteristics from the epidemic clone circulating in the same hospital from 1997 and designed "Rome clone," which was susceptible to erythromycin, clindamycin, and spectinomycin and belonged to the II::NH::C genetic background. A high genetic similarity between this Rome clone and the previously classified Archaic and Iberian clones was found, because they shared the same allelic profile (ST247), probably originating from the same S. aureus ancestor of the Iberian MRSA strains. Therefore, the strains responsible for the outbreak, with vancomycin MICs 2-4 mg/L, are variant clones, showing the genotype of the "Rome clone," the ST247 in association with SCC mec type IA (ST247-MRSA-IA), and are characterized by a uniform susceptibility to fosfomycin.  相似文献   
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