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41.
AIM: To assess a relationship between longitudinal changes in liver fat content and biochemical parameters in obese children after 1-year nutritional intervention.METHODS: Forty-six obese children, 21 males and 25 females, aged 6-14 years, underwent metabolic measurements, liver ultrasonography (US) and chemical-shift magnetic resonance imaging (MRI) examinations at baseline and after 1-year nutritional intervention. A child was defined obese if her/his body mass index (BMI) was above the age- and sex-adjusted BMI Cole’s curve passing through the cut-off of 30 kg/m2 at 18 years. BMI Z scores were calculated and adjusted for age and gender by using the Cole’s LMS-method and Italian reference data. Biochemistry included serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Abdominal US and chemical-shift MRI were performed according to a randomized sequence. The same radiologist performed US by a GE Logiq 9 (General Electric Healthcare Medical Systems, Milwaukee, WI, United States) using a 3.5-MHz convex array transducer. Liver echogenicity was evaluated independently on videotape by 3 radiologists unaware of the child and MRI outcomes, and a consensus was established. Another experienced radiologist, unaware of the child and US data, performed the abdominal chemical-shift MRI with a 1-t system NT-Intera (Philips Medical Systems, Best, The Netherlands) and a phased-array coil. Liver fat fraction (FF) on MRI was judged elevated when greater than 9%. A FF > 18% was considered expressing more severe cases of fatty liver according to Fishbein. A nutritional-behavioral intervention was recommended to promote a normocaloric balanced diet and active lifestyle based on the Italian guidelines for treatment of childhood obesity.RESULTS: Compared to baseline, at the end of intervention children showed lower intakes of energy (mean ± SD: 2549 ± 1238 Kcal vs 1770 ± 622 Kcal, P < 0.0001), total fat (90 ± 47 g vs 52 ± 23 g, P < 0.0001), carbohydrates (356 ± 174 g vs 241 ± 111 g, P = 0.001), and protein (99 ± 48 g vs 75 ± 23 g, P = 0.006) intakes. Prevalence of FF ≥ 9% declined from 34.8% to 8.7% (P < 0.01), with a mean reduction of 7.8% (95%CI: 5.0-10.6). At baseline, FF was associated with liver biochemical parameters (maximum P < 0.001). At the end of the intervention association was found with AST (P = 0.017). Change of FF was associated with change in AST (P = 0.027) and ALT (P = 0.024). Rate of increased liver echogenicity declined from 45.6% to 21.7% (P < 0.0001). Liver echogenicity was associated with ALT at baseline only (P < 0.001). An age- and sex- adjusted multiple regression analysis showed that FF change was independently associated with change in serum AST (adjusted regression coefficient 0.348, P = 0.048).CONCLUSION: The results suggest that in obese children longitudinal changes in liver fat content based on MRI may be associated with change in serum transaminases suggesting novelty in monitoring nonalcoholic fatty liver disease.  相似文献   
42.
Sleep and Breathing - Excessive daytime sleepiness (EDS) and fatigue are some of the most frequent symptoms in neurological diseases and could impact on quality of life by increasing the risk of...  相似文献   
43.
Summary. α-interferon (α-IFN) has been used to treat chronic non-A non-B hepatitis in thalassaemic patients with response rates from 45% to 83%. Unfortunately, treatment with α-IFN is associated with side-effects which have a negative effect on the quality of life of the patient. Therefore it would be useful if we could distinguish in advance those patients who would benefit from such therapy from those who would not. In the present study we found that the modification of lymphocyte subsets 20 h after the administration of the first dose of α-IFN revealed that relative numbers of T helper lymphocytes (CD4+) increased in three non-responding patients and decreased in five responding patients, whereas those of T suppressor lymphocytes (CD8+), and natural killer cells (CD57+. CD16+) decreased in non-responding patients and increased in responding patients. Therefore analysis of the lymphocyte subsets CD4, CD8, CD57 and CD16 before and 20 h after the administration of α-IFN can be used to predict the clinical response to treatment with α-IFN.  相似文献   
44.
45.
Eur J Clin Invest 2012; 42 (10): 1068-1078 ABSTRACT: Background In many countries, the introduction of generic proton pump inhibitors (PPIs) onto the pharmaceutical market increased the phenomenon of therapeutic substitution in acid-related disorders (ARDs). Aim To investigate the treatment of ARDs in an Italian primary care setting from 2005 to 2008 by verifying: (i) dynamics of PPI prescribing; (ii) predictors of PPI switching; and (iii) healthcare resource consumption costs. Methods This was a retrospective cohort study of 102 general practitioners (GPs) who managed an average of 150?000 inhabitants in Naples. Multilevel logistic regression was used to assess the potential predictors of both PPI switching and termination. Primary care costs were expressed as the cost of ARD management per PPI user year. Results The percentage of PPI users with ARD increased from 5·5% (2005) to 7·0% (2008) (P?相似文献   
46.
Aberrant promoter hypermethylation is a mechanism of tumour suppressor gene inactivation. We explored aberrant promoter hypermethylation of multiple genes in 88 human immunodeficiency virus (HIV)-non Hodgkin lymphomas (NHL), 25 post-transplant lymphoproliferative disorders (PTLD) and five common variable immunodeficiency (CVI)-related NHL. Twenty-six of 79 (32.9%) HIV-NHL, eight of 14 (57.1%) PTLD and two of five (40.0%) CVI-NHL showed aberrant hypermethylation of O6-methylguanine-DNA methyltransferase (MGMT). Aberrant hypermethylation of death-associated protein-kinase (DAP-K) occurred in 70 of 84 (83.3%) HIV-NHL, 19 of 25 (72.0%) PTLD and three of five (60.0%) CVI-NHL. These data implicate MGMT and DAP-K hypermethylation in lymphomagenesis of immunodeficient hosts. In particular, promoter hypermethylation of DAP-K represents the most frequent molecular alteration yet identified in immunodeficiency-related lymphomas.  相似文献   
47.
The potential of immunotherapy with autologous virus-specific T cells to affect the course of feline immunodeficiency virus (FIV) infection was explored in a group of specific-pathogen-free cats infected with FIV a minimum of 10 months earlier. Popliteal lymph node cells were stimulated by cocultivation with UV-inactivated autologous fibroblasts infected with recombinant vaccinia viruses expressing either FIV gag or env gene products, followed by expansion in interleukin-2. One or two infusions of both Gag- and Env-stimulated cells resulted in a slow increase in FIV-specific gamma interferon-secreting T cells in the circulation of cats. In the same animals, viral set points fluctuated widely during the first 2 to 3 weeks after adoptive transfer and then returned to pretreatment levels. The preexisting viral quasispecies was also found to be modulated, whereas no novel viral variants were detected. Circulating CD4(+) counts underwent a dramatic decline early after treatment. CD4/CD8 ratios remained instead essentially unchanged and eventually improved in some animals. In contrast, a single infusion of Gag-stimulated cells alone produced no apparent modulations of infection.  相似文献   
48.
Ti-6Al-7Nb samples treated by innovative multi-step chemical and thermal processes were characterized in order to evaluate their surface properties and cell interaction. The main object was to asses if the treatments were effective in order to obtain a surface presenting at the same time bone-like apatite induction ability, low metal ion release, good cell response and high protein binding. The morphology, crystallographic structure, porosity and wettability of the treated materials were investigated, as well as their interaction with simulated body fluid during soaking for different times. Cytotoxicity, protein adsorption tests and in vitro fibroblast and osteoblast-like cell cultures were also performed.  相似文献   
49.
Losi P  Lombardi S  Briganti E  Soldani G 《Biomaterials》2004,25(18):4447-4455
One of the major problems when using small-diameter vascular grafts in arterial reconstruction is the development of platelet-rich thrombi as a consequence of blood contact with artificial surfaces. The degree of occlusion is certainly affected by the thrombogenicity of the internal surface that seems to play a key role in patency and long-term wound healing of grafts. In this study, the blood compatibility of Cardiothane (CA) vascular grafts was investigated. The CA material, a blend of polyurethane and polydimethylsiloxane that has shown relatively good physical and biocompatibility properties, was manufactured into vascular grafts by the instrument named "spray-machine". Grafts with different luminal surface porosity were produced using increasing CA concentrations by the "spray-machine" and the blood compatibility was evaluated in vitro by a circulation system in which the human blood was allowed to interact with the material in a well-controlled setting. The samples of circulating blood were collected at different times of circulation and platelet adhesion and activation were studied. Grafts with a highly porous luminal surface induced a lower adhesion and activation of platelets in vitro than the low-porosity ones. These results underlined the importance of the microgeometry of the graft luminal surface in the interaction with blood.  相似文献   
50.
OBJECTIVE: We tested the effects of chloroquine (CQ) on glycosylation of HIV particles and in combination with protease inhibitors (PIs) on HIV replication and on P-glycoprotein (P-gp)/multidrug resistance protein-1 (MRP1). DESIGN: CD4 cell lines were infected with laboratory strains and peripheral blood mononuclear cells were infected with primary isolates for evaluation of the anti-HIV effects. Peripheral blood lymphocytes were evaluated for of P-gp and MRP1 functions. METHODS: HIV replication was assessed by enzyme-linked immunosorbent assay. HIV glycosylation was measured by metabolic labeling of viral particles with [H] glucosamine. Synergism was tested using isobolograms. P-gp and MRP1 functions were assayed using rhodamine 123 (Rh123) and carboxyfluorescein (CF) efflux assays, respectively. RESULTS: CQ alone inhibited HIV replication and glycosylation in a dose-dependent manner. In combination with indinavir (IDV), ritonavir, or saquinavir (SQV), CQ had a synergistic effect at concentrations found in plasma of subjects receiving malaria prophylaxis. CQ decreased the 50% effective concentration of IDV in primary isolates from Africa and restored the response to IDV or SQV in 3 PI-resistant isolates. CQ increased the block of Rh123 and CF efflux activity exerted by PIs. CONCLUSION: The inhibitory effects of CQ on HIV glycosylation are associated with synergistic effects in combination with PIs. The CQ/PI combination exerts combined inhibitory effects on P-gp and MRP1 function.  相似文献   
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