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51.

Evidence is provided here supporting the existence of a novel autacoid mechanism negatively modulating mast cell behaviour in response to noxious stimuliin vivo; hence, the denomination “autacoid local inflammation antagonism” (ALIA). In particular, as lipid amides of theN-acylethanolamine type have been reported to accumulate in tissues in degenerative inflammatory conditions, we examined whether theseN-acylated lipids could exert regulatory effects on mast cell activationin vivo. The results reported show that both long- and short-chainN-acylethanolamines, when systemically administered, are effective in reducing mast cell degranulation induced by local injection of substance P in the earpinna of developing rats. These and other data suggest that the endogenous production ofN-acylethanolamines may constitute a local autocrine/paracrine response for the negative feedback control of mast cell responses to various activating signals. Such a process may be of physio-pathological relevance in the regulation of functional neuroimmune-mast cell interactions.

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52.
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG.  相似文献   
53.
BACKGROUND: Up to 20 million persons are infected with the human retroviruses human T-lymphotropic virus (HTLV)-I and HTLV-II globally. Most data on the seroprevalence of HTLV-I and HTLV-II in Europe are from studies of low-risk blood donors or high-risk injection drug users (IDUs). Little is known about the general population. METHODS: A prospective anonymous study of HTLV-I and HTLV-II seroprevalence among 234,078 pregnant women in Belgium, France, Germany, Italy, Portugal, Spain, and the United Kingdom was conducted. Maternal antibody status was determined by standard methods using sera obtained for routine antenatal infection screens or eluted from infant heel prick dried blood spots obtained for routine neonatal metabolic screens. RESULTS: Anti-HTLV-I/II antibodies were detected and confirmed in 96 pregnant women (4.4 per 10,000, 95% confidence interval [CI]: 3.5-5.2). Of these, 73 were anti-HTLV-I, 17 were anti-HTLV-II, and 6 were specifically anti-HTLV but untyped. The seroprevalence ranged from 0.7 per 10,000 in Germany to 11.5 per 10,000 in France. CONCLUSIONS: Pregnant women better reflect the general population than blood donors or IDUs. The seroprevalence of HTLV-I and HTLV-II in Western Europe is 6-fold higher among pregnant women (4.4 per 10,000) than among blood donors (0.07 per 10,000). These data provide a robust baseline against which changes in HTLV-I and HTLV-II seroprevalence in Europe can be measured.  相似文献   
54.
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms.  相似文献   
55.
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS.  相似文献   
56.
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D.  相似文献   
57.
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée.  相似文献   
58.
Preservation of vascular endothelium integrity and functionality represents an unmet medical need. Indeed, endothelial dysfunction leads to decreased nitric oxide biosynthesis, which is prodromic of hypertension and hypercoagulability. In this panorama, the nutraceutical supplement Taurisolo®, a polyphenolic extract from Aglianico cultivar grape, rich in catechin and procyanidins, was evaluated as a vasoprotective, vasorelaxing, anti-hypertensive and anti-coagulant agent in: cell lines, isolated vessels, in vivo models of chronic hypertension and hypercoagulability, and in clinical tests of endothelial reactivity. Taurisolo® demonstrated to fully protect vascular cell viability from oxidative stimulus at 100 µg/mL and evoke vasorelaxing effects (Emax = 80.6% ± 1.9 and pEC50 = 1.19 ± 0.03) by activation of the Sirtuins-AMPK-pathway. Moreover, Taurisolo®, chronically administered at 20 mg/Kg/die in in vivo experiments, inhibited the onset of cardiac hypertrophy (heart weight/rat weight = 3.96 ± 0.09 vs. 4.30 ± 0.03), hypercoagulability (decrease of fibrinogen vs. control: p < 0.01) and hypertension (mean of Psys: 200 ± 2 vs. control 234 ± 2 mmHg) and improved endothelial function (Emax = 88.9% ± 1.5 vs. control 59.6% ± 3.6; flow-mediated dilation in healthy volunteers after 400 mg twice daily for 8 weeks vs. baseline: p = 0.019). In conclusion, Taurisolo® preserves the vascular function against ox-inflamm-ageing process and the consequent cardiovascular accidents.  相似文献   
59.
Individual differences in the chronotype, an attitude that best expresses the individual circadian preference in behavioral and biological rhythms, have been associated with cardiometabolic risk and gut dysbiosis. Up to now, there are no studies evaluating the association between chronotypes and circulating TMAO concentrations, a predictor of cardiometabolic risk and a useful marker of gut dysbiosis. In this study population (147 females and 100 males), subjects with the morning chronotype had the lowest BMI and waist circumference (p < 0.001), and a better metabolic profile compared to the other chronotypes. In addition, the morning chronotype had the highest adherence to the Mediterranean diet (p < 0.001) and the lowest circulating TMAO concentrations (p < 0.001). After adjusting for BMI and adherence to the Mediterranean diet, the correlation between circulating TMAO concentrations and chronotype score was still kept (r = −0.627, p < 0.001). Using a linear regression analysis, higher chronotype scores were mostly associated with lower circulating TMAO concentrations (β = −0.479, t = −12.08, and p < 0.001). Using a restricted cubic spline analysis, we found that a chronotype score ≥59 (p < 0.001, R2 = −0.824) demonstrated a more significant inverse linear relationship with circulating TMAO concentrations compared with knots <59 (neither chronotype) and <41 (evening chronotype). The current study reported the first evidence that higher circulating TMAO concentrations were associated with the evening chronotype that, in turn, is usually linked to an unhealthy lifestyle mostly characterized by low adherence to the MD.  相似文献   
60.
We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners.  相似文献   
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