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31.
The NK cell maturation from CD34(+) Lin(-) hematopoietic cell precursors is a complex process that requires the direct contact with stromal cells and/or the synergistic effect of different cytokines. In this study we show that IL-21 is capable of inducing an accelerated NK cell maturation when added to cultures of CD34(+) Lin(-) cells isolated from human cord blood supplemented with IL-15, Flt3-L and SCF. After 25 days of culture, 50% of CD56(+) cells expressed various NK cell markers including the NKp46 and NKp30 triggering receptors, the CD94/NKG2A inhibitory receptor and CD16. At day 35, substantial fractions of NK cells expressed KIR, CD8 and CD2, i.e. surface markers expressed by mature NK cells, that are virtually undetectable in developing NK cells cultured in the absence of IL-21. Remarkably, similar to mature NK cells all these markers were included in the CD56(dim) cell fraction, while the CD56(bright) population was only composed of CD94/NKG2A(-) and CD94/NKG2A(+) cells. Thus, IL-21 allows the induction of a full NK cell maturation in vitro and offers an important tool for dissecting the molecular mechanisms involved in different steps of NK cell maturation and in the acquisition of a mature KIR repertoire.  相似文献   
32.
Summary: CD40 is a member of the tumor necrosis factor receptor family, which is expressed by a variety of cells including B cells, macrophages, dendritic cells, and other nonimmune cell types. CD40 activation is critical for B‐cell proliferation, immunoglobulin (Ig)‐isotype switching, and germinal center formation. In physiological conditions, the activation of CD40 occurs by binding to its natural ligand, CD154, which is expressed on activated T cells. The in vivo critical role of CD40–CD154 interaction on B‐cell differentiation and isotype switching is provided by the discovery that mutations in either CD40 or CD154 gene cause the hyper IgM syndrome, termed HIGM3 or HIGM1, respectively, characterized by very low levels of serum IgG, IgA, and IgE, with normal or elevated IgM, associated with a defective germinal center formation. Originally considered humoral primary immunodeficiencies, the clinical features and the defect of T‐cell priming, resulting from a defective T–B cell or dendritic cell interaction, is now considered as combined immunodeficiencies. In this article, we present a comprehensive overview of the clinical, genetic, and immunological features of patients with hyper IgM syndrome due to CD40 mutations.  相似文献   
33.
Bacteria of the genus Wolbachia constitute a group of intracellular and maternally inherited micro-organisms that are widespread in arthropods, inducing several reproductive disorders such as cytoplasmic incompatibility in their hosts. Considering relevant biological implications related to the presence of Wolbachia in several insect orders, for example its potential role as mechanism for rapid speciation and as vehicle to drive genetic markers in wild populations of vectors of medical and veterinary interest, we carried out an extensive polymerase chain reaction survey to detect Wolbachia in several species of mosquito belonging to genera involved in the transmission of pathogens. Five species out of 26 tested have shown to be infected; for four of them this is the first evidence of the Wolbachia infection. A phylogenetic analysis was also performed, positioning the five Wolbachia strains in the phyletic subdivision B.  相似文献   
34.
The purpose of this study was to identify the most cost effective method for screening subjects for hepatitis B vaccination. Such a method would ideally permit detection of all susceptible individuals at the lowest possible cost.Two-hundred-five hospital workers from the Piedmont region of Italy participated in the study. The sero-epidemiological conditions of this group with regard to hepatitis B markers was representative of hospital workers in this region as a whole. All subjects, excluding carriers, persons with anti-HBs titers 10 mIU and subjects positive for anti-HBc at a 1/100 dilution, were vaccinated. Their responses were evaluated 15 days and 1 month after vaccination. The presence of a booster effect following vaccination was correlated with the immunological status of the subject at the time of pre-vaccination screening.In the light of the results obtained, 5 screening procedures and the procedure of vaccination without screening were evaluated. The most cost effective screening strategy proved to be that of sequential testing for anti-HBc, anti-HBs and finally HBsAg and vaccination of the following subjects: those who were negative for anti-HBc, those who were anti-HBc-positive with anti-HBs titers 10相似文献   
35.
More than one year has passed since the first cases of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome (SARS)-CoV-2 coronavirus were reported in Wuhan (China), rapidly evolving into a global pandemic. This infectious disease has become a major public health challenge in the world. Unfortunately, to date, no specific antivirals have been proven to be effective against COVID-19, and although a few vaccines are available, the mortality rate is not decreasing but is still increasing. One therapeutic strategy has been focused on infection prevention and control measures. In this regard, the use of nutraceutical supports may play a role against some aspect of the infection, particularly the inflammatory state and the immune system function of patients, thus representing a strategy to control the worst outcomes of this pandemic. For this reason, we performed an overview including meta-analyses and systematic reviews to assess the association among melatonin, vitamin C, vitamin D, zinc supplementation and inflammatory markers using three databases, namely, MEDLINE, PubMed Central and the Cochrane Library of Systematic Reviews. According to the evidence available, an intake of 50,000 IU/month of vitamin D showed efficacy in CRP. An amount of 1 to 2 g per day of vitamin C demonstrated efficacy both in CRP and endothelial function, and a dosage of melatonin ranging from 5 to 25 mg /day showed good evidence of efficacy in CRP, TNF and IL6. A dose of 50 mg/day of elemental zinc supplementation showed positive results in CRP. Based on the data reported in this review, the public health system could consider whether it is possible to supplement the current limited preventive measures through targeted nutraceutical large-scale administration.  相似文献   
36.
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   
37.
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.  相似文献   
38.
Bisphenol A (BPA) is an organic chemical compound widely used for manufacturing plastics. BPA exposure originates principally from the diet, but it can also originate from dermal contact. In over 90% of individuals, including pregnant women, BPA is detectable in several body fluids. The effects of this exposure on the fetus are under active investigation in several research laboratories. The aim of our work was to study the impact of prenatal exposure to BPA in the liver of rat fetuses from a sex-dependent point of view. We particularly investigated the effects of prenatal BPA exposure on hepatic lipids because of their crucial role, not only for the liver, but also for the whole-body functions. Our results demonstrate that the liver of rat fetuses, in utero exposed to a very low dose of BPA (2.5 µg/kg/day), displays significant modulations with regard to proteins involved in cholesterol and fatty acid biosynthesis and trafficking. Moreover, an impact on inflammatory process has been observed. All these effects are dependent on sex, being observable only in female rat fetuses. In conclusion, this work demonstrates that maternal exposure to BPA compromises hepatic lipid metabolism in female offspring, and it also reveals the perspective impact of BPA on human health at doses currently considered safe.  相似文献   
39.

Asian American immigrant (AAI) women may have suboptimal 24-h activity patterns due to traditional gender role and caregiving responsibilities. However, little is known about their objectively-measured activity. We measured AAI women’s 24-h activity patterns using accelerometry and examined cultural correlates of time in sedentary behavior (SB), light intensity physical activity (LIPA), moderate-to-vigorous physical activity (MVPA) and sleep. Seventy-five AAI women completed surveys on acculturation (years of U.S. residency and English proficiency), discrimination, and sleep quality, and 7 days of wrist- and hip-accelerometer monitoring. Linear regression was conducted controlling for age, BMI, and education. We also compared activity patterns across Asian subgroups (East, Southeast, South Asians). On average, AAI women had 33 min of MVPA, 6.1 h of LIPA, 10 h of SB, and 5.3 h of sleep per day. South Asian women had the longest SB and the shortest sleep and MVPA hours. English proficiency was negatively related to MVPA (p?=?0.03) and LIPA (p?<?0.01). Years of U.S. residency was positively related to SB (p?=?0.07). Discrimination was related to shorter (p?=?0.03) and poorer quality sleep (p?=?0.06). Culturally-tailored programs targeting SB and sleep and integrating coping strategies against discrimination could help optimize AAI women’s 24-h activity patterns.

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40.
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