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91.
We evaluated phenotypic and functional parameters of immune restoration of 27 HIV-infected patients on highly active antiretroviral therapy (HAART) (HIV-cases) with HIV-RNA levels below detectable limits at least during 18 months, and CD4+ cell per microliter higher than 500 at the moment of the study and lower than 300 anytime before. These patients were compared with 11 HIV-controls that never had less than 500 CD4+ cell per microliter and 20 healthy-controls (HIV seronegative subjects) in a cross-sectional study. HIV-cases had lower counts of naïve CD4+ than HIV-controls and healthy-controls. HIV-patients (both HIV-cases and HIV-controls) showed higher values of naïve and memory CD8+ counts than healthy-controls. TREC-bearing cell levels were significantly lower in HIV-cases than in healthy-controls. Peripheral blood mononuclear cells (PBMC) cultures, HIV-cases had lower values in proliferation to streptokinase (SK) and tetanus toxin (TT) than in healthy-controls. HIV-cases had lower IFN-γ and higher IL-5 production with pokeweed than healthy-controls (P < 0.01). However, IL-5 production of HIV-cases after TT stimulation was lower than in HIV-controls and healthy-controls. Total IgG and IgG1 levels were significantly higher in HIV-cases than in HIV-controls and healthy-controls. Also, IgM levels were significantly higher in HIV-cases than in healthy-controls. Nevertheless, IgG2 levels were significantly lower in HIV-cases and HIV-controls than in healthy-controls. The levels of specific Igs antipneumococcal capsular polysaccharide and TT were significantly lower in HIV-cases than in healthy-controls. HIV-patients with a previous state of severe-moderate immunosuppression normalizing their CD4+ counts have a incomplete immune reconstitution after HAART. Long-term consequences of this subclinical immune deficiency remain to be determined.  相似文献   
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Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes.  相似文献   
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Overexpression of cytokines in inflamed joints plays an important role in joint inflammation and in damage to articular tissue. Biological agents aimed at specifically antagonising tumour necrosis factor (TNF) are effective in the treatment of adult rheumatoid arthritis. A recent trial of etanercept, a genetically engineered fusion protein consisting of the Fc domain of human IgG1 and the TNF receptor p75, has demonstrated that this agent is also well tolerated and effective in patients with juvenile idiopathic arthritis (JIA). Etanercept offers a promising new alternative for patients with JIA who have persistently active arthritis despite treatment with methotrexate. Further studies are needed to clarify whether etanercept is equally effective in the various onset types of JIA (oligoarthritis, polyarthritis and systemic arthritis), whether it can modify disease progression and whether it can be administered safely for long periods of time to children.  相似文献   
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As a part of our interest in the performance of [Ti2(OC2H5)8Cl]2Mg2(μ-Cl)2 as Ziegler-Natta catalyst, the polymerization of styrene with a toluene solution of this compound and methyl-aluminoxane as cocatalyst was performed. It was found that the present catalytic system promotes the syndiospecific polymerization of styrene with high stereoregularity and the results were compared with those obtained with MgCl2-supported or unsupported Ti(OC2H5)4 catalysts. Determination of the titanium oxidation states and electron spin resonance (ESR) measurements both in the absence and in the presence of styrene were carried out for all the catalytic systems aimed at shedding some light on the nature of the active species.  相似文献   
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Cryopreserved human peripheral blood mononuclear cells (PBMC) were tested for natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) and for high-affinity (29°C) and total (4°C) rosette formation with sheep erythrocytes. PBMC produced variable NK activity following freezing and thawing, but consistently reacted well in ADCC. A significant correlation was found between low NK activity and a decreased percentage of low-affinity rosette-forming cells. On the contrary, the number of large granular lymphocytes (LGL), among which NK cells are restricted, and the reactivity with the monoclonal antibody OKT10, which recognizes the majority of LGL in the peripheral blood, were not significantly altered by cryopreservation. Cryopreserved cells proved to be excellent controls for determining the day-to-day variability of the NK assay and for selecting optimum conditions for this test in the clinical immunology laboratory.  相似文献   
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