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41.
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   
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This study aimed to determine whether pupils who have breakfast just before a cognitive demand, do not regularly skip breakfast, and consume a high-quality breakfast present higher cognitive performance than those who do not; furthermore, to establish differences according to their nutritional status. In this study, 1181 Chilean adolescents aged 10–14 years participated. A global cognitive score was computed through eight tasks, and the body mass index z-score (BMIz) was calculated using a growth reference for school-aged adolescents. The characteristics of breakfast were self-reported. Analyses of covariance were performed to determine differences in cognitive performance according to BMIz groups adjusted to sex, peak height velocity, physical fitness global score, and their schools. A positive association was found in adolescents’ cognitive performance when they had breakfast just before cognitive tasks, did not regularly skip breakfast, presented at least two breakfast quality components, and included dairy products. No significant differences were found between breakfast components, including cereal/bread and fruits/fruit juice. Finally, pupils who were overweight/obese who declared that they skipped breakfast regularly presented a lower cognitive performance than their normal-BMIz peers. These findings suggest that adolescents who have breakfast just prior to a cognitive demand and regularly have a high quality breakfast have better cognitive performance than those who do not. Educative nutritional strategies should be prioritized, especially in “breakfast skippers” adolescents living with overweight/obesity.  相似文献   
43.
Background: Vitamin D plays a pivotal role in calcium and phosphorus metabolism, also influencing bone tissue. Several studies have reported that vitamin D blood levels were significantly lower in people with obesity, probably due to its uptake by the adipose tissue. Clinical studies that investigated the changes of circulating levels of vitamin D following weight loss reported controversial data. A very low-calorie ketogenic diet is acknowledged as a reliable treatment to achieve a rapid weight loss. Therefore, we investigated the effect of weight loss, consequent to a very low-calorie ketogenic diet, on vitamin D blood concentrations. Methods: A cohort of 31 people with obesity underwent a very low-calorie ketogenic diet for 10–12 weeks. The serum concentrations of vitamin D, parathormone, calcium and phosphorous were measured before and after weight loss; they were compared to a control group of 20 non-obese, non-diabetic, age- and gender-matched persons. Results: Patients with obesity had a higher habitual intake of vitamin D than the control group (p < 0.05). However, the vitamin D blood levels of the obese group were significantly lower than those of the control group (p < 0.005) and they increased after weight loss (p < 0.001). At baseline, vitamin D blood concentrations of the persons with obesity were significantly correlated with both fat mass–kg (r = −0.40; p < 0.05) and body mass index (r = −0.47; p < 0.01). Following very low-calorie ketogenic diet, the change in vitamin D serum concentrations was correlated only with the change in fat mass–kg (r = −0.43; p < 0.01). Conclusion: This study confirmed that patients with obesity have lower vitamin D levels that normalize after significant weight loss, supporting the hypothesis that vitamin D is stored in the adipose tissue and released following weight loss.  相似文献   
44.
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   
45.
Our purpose was to review and analyse the impact of pyrethroids and organophosphates exposure on human semen parameters. A comprehensive literature search was performed through MEDLINE via PubMed, Scopus and Webscience. Only cohort studies examining semen parameters in workers or general populations exposed to pyrethroids or organophosphates were included. Ejaculate volume, sperm count, concentration, motility, viability, normal morphology and seminal pH alterations were pooled using the Cochran–Mantel–Haenszel Method with the random effect model and expressed as weighted mean difference, risk ratios, 95% confidence intervals and p-values. Seven cross-sectional studies regarding pyrethroids were included. Four of them were eligible for meta-analysis. The only parameter affected by pyrethroid exposure was normal sperm morphology (WMD-7,61%, 95%CI –11,92 to −3,30;p = 0,0,005). Nine studies were selected to evaluate the impact of organophosphates on semen parameters with six of them eligible for meta-analysis. A significant reduction was detected for the following: ejaculate volume (WMD −0,47ml, 95%CI −0,69 to −0,25; p < 0,0001), sperm count (WMD-40,03, 95%CI −66,81 to −13,25;p = 0,003), concentration (WMD-13,69 x10⁶/mL, 95%CI −23, 27 to-4,12;p = 0,005) and motility (WMD −5,70%, 95%CI −12,89 to 1,50;p = 0,12). Despite the increase in sperm abnormality, it has been shown that pyrethroids are unrelated to reduced sperm quality. However, the negative association of organophosphates with spermatogenesis is noteworthy.  相似文献   
46.
The determinants of the susceptibility to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection and severe coronavirus disease 2019 (COVID-19) manifestations are yet not fully understood. Amino-bisphosphonates (N-BPs) have anti-inflammatory properties and have been shown to reduce the incidence of lower respiratory infections, cardiovascular events, and cancer. We conducted a population-based retrospective observational cohort study with the primary objective of determining if oral N-BPs treatment can play a role in the susceptibility to development of severe COVID-19. Administrative International Classification of Diseases, Ninth Revision, Clinical ModificationI (ICD-9-CM) and anatomical-therapeutic chemical (ATC) code data, representative of Italian population (9% sample of the overall population), were analyzed. Oral N-BPs (mainly alendronate and risedronate) were included in the analysis, zoledronic acid was excluded because of the low number of patients at risk. Incidence of COVID-19 hospitalization was 12.32 (95% confidence interval [CI], 9.61–15.04) and 11.55 (95% CI, 8.91–14.20), of intensive care unit (ICU) utilization because of COVID-19 was 1.25 (95% CI, 0.38–2.11) and 1.42 (95% CI, 0.49–2.36), and of all-cause death was 4.06 (95% CI, 2.50–5.61) and 3.96 (95% CI, 2.41–5.51) for oral N-BPs users and nonusers, respectively. Sensitivity analyses that excluded patients with prevalent vertebral or hip fragility fractures and without concomitant glucocorticoid treatment yielded similar results. In conclusion, we found that the incidence of COVID-19 hospitalization, intensive care unit (ICU) utilization, and COVID-19 potentially related mortality were similar in N-BPs–treated and nontreated subjects. Similar results were found in N-BPs versus other anti-osteoporotic drugs. We provide real-life data on the safety of oral N-BPs in terms of severe COVID-19 risk on a population-based cohort. Our results do not support the hypothesis that oral N-BPs can prevent COVID-19 infection and/or severe COVID-19; however, they do not seem to increase the risk. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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The purpose of this retrospective study was to determine the diagnostic and therapeutic usefulness of gut angiography in patients with massive upper gastrointestinal bleeding from a nonvariceal source. All patients (n = 64) in this category who underwent a gut angiogram between 1980 and 1986 were studied. Pre-angiogram endoscopy was attempted in all patients and was nondiagnostic in 14 (22%). Contrast extravasation at angiography was seen in 25 of 64 patients (39%), and in over half of these patients endoscopy was nondiagnostic (n = 11) or wrong (n = 3). Attempts to control bleeding in this group by selective arterial embolization (n = 14) or intra-arterial vasopressin (n = 11) successfully averted operation in 13 of 25 patients (52%) and was associated with a 50% reduction in mortality (83% versus 38%). Selective embolization of vessels thought to be bleeding on clinical grounds without evidence of contrast extravasation (i.e., "blind" embolization) was not helpful in controlling hemorrhage. Urgent gut angiography in patients with massive upper gastrointestinal bleeding of arteriocapillary source is a useful diagnostic and therapeutic maneuver and warrants continued application in this group of poor-risk patients.  相似文献   
50.
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