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991.
Spirulina is a microscopic, filamentous cyanobacterium that grows in alkaline water bodies. It is extensively utilized as a nutraceutical food supplement all over the world due to its high levels of functional compounds, such as phycocyanins, phenols and polysaccharides, with anti-inflammatory, antioxidant, immunomodulating properties both in vivo and in vitro. Several scientific publications have suggested its positive effects in various pathologies such as cardiovascular diseases, hypercholesterolemia, hyperglycemia, obesity, hypertension, tumors and inflammatory diseases. Lately, different studies have demonstrated the neuroprotective role of Spirulina on the development of the neural system, senility and a number of pathological conditions, including neurological and neurodegenerative diseases. This review focuses on the role of Spirulina in the brain, highlighting how it exerts its beneficial anti-inflammatory and antioxidant effects, acting on glial cell activation, and in the prevention and/or progression of neurodegenerative diseases, in particular Parkinson’s disease, Alzheimer’s disease and Multiple Sclerosis; due to these properties, Spirulina could be considered a potential natural drug.  相似文献   
992.
BACKGROUND: Phthalates may pose a risk for perinatal developmental effects. An important question relates to the choice of suitable biological matrices for assessing exposure during this period. OBJECTIVES: This study was designed to measure the concentrations of phthalate diesters or their metabolites in breast milk, blood or serum, and urine and to evaluate their suitability for assessing perinatal exposure to phthalates. METHODS: In 2001, 2-3 weeks after delivery, 42 Swedish primipara provided breast milk, blood, and urine samples at home. Special care was taken to minimize contamination with phthalates (e.g., use of a special breast milk pump, heat treatment of glassware and needles, addition of phosphoric acid). RESULTS: Phthalate diesters and metabolites in milk and blood or serum, if detected, were present at concentrations close to the limit of detection. By contrast, most phthalate metabolites were detectable in urine at concentrations comparable to those from the general population in the United States and in Germany. No correlations existed between urine concentrations and those found in milk or blood/serum for single phthalate metabolites. Our data are at odds with a previous study documenting frequent detection and comparatively high concentrations of phthalate metabolites in Finnish and Danish mothers' milk. CONCLUSIONS: Concentrations of phthalate metabolites in urine are more informative than those in milk or serum. Furthermore, collection of milk or blood may be associated with discomfort and potential technical problems such as contamination (unless oxidative metabolites are measured). Although urine is a suitable matrix for health-related phthalate monitoring, urinary concentrations in nursing mothers cannot be used to estimate exposure to phthalates through milk ingestion by breast-fed infants.  相似文献   
993.
994.
IntroductionExposure to feather bedding may be an unnoticed cause of hypersensitivity pneumonitis (HP) and idiopathic pulmonary fibrosis (IPF). Thus, an in-depth clinical study of the diagnosis of patients with suspected HP and IPF is required in order to determine their etiologies. The objective of the present study is to raise awareness of HP and pulmonary fibrosis due to exposure to feather bedding, and to study the prevalence and describe long-term outcomes.MethodsWe describe a series of 33 patients diagnosed with HP and pulmonary fibrosis due to feather bedding exposure and followed over a 10-year period. The patients were from a subgroup of 127 individuals with HP undergoing in-depth evaluation using a diagnostic protocol at a regional referral center.ResultsEleven (33%) patients were clinically diagnosed with acute HP and 22 (67%) with chronic HP. Ten (45%) chronic HP patients showed a high resolution computed tomography (HRCT) pattern of usual interstitial pneumonia (UIP) with suspected IPF. The prevalence of HP was 6.2/100 000 feather bedding users (compared with 54.6 per 100 000 bird-breeders). The survival rates of patients over the 10-year period was 100% for acute HP and 64% for chronic HP.ConclusionsIn a series of HP patients, the diagnosis was attributed to feather bedding exposure in 26%. UIP pattern on HRCT was present in nearly half of the chronic cases. The survival of patients with chronic HP at ten years was 64%, despite avoiding further exposure.  相似文献   
995.
Increasing attention is focused on developing biomaterials as temporary scaffolds that provide a specific environment and microstructure for bone tissue regeneration. The aim of the present work was to synthesize silicon-doped biomimetic multi-phase composite scaffolds based on bioactive inorganic phases and biocompatible polymers (poly(ε-caprolactone), PCL) using simple and inexpensive methods. Porous multi-phase composite scaffolds from cuttlefish bone were synthesized using a hydrothermal method and were further impregnated with (3-aminopropyl)triethoxysilane 1–4 times, heat-treated (1000 °C) and coated with PCL. The effect of silicon doping and the PCL coating on the microstructure and mechanical and biological properties of the scaffolds has been investigated. Multi-phase scaffolds based on calcium phosphate (hydroxyapatite, α-tricalcium phosphate, β-tricalcium phosphate) and calcium silicate (wollastonite, larnite, dicalcium silicate) phases were obtained. Elemental mapping revealed homogeneously dispersed silicon throughout the scaffolds, whereas silicon doping increased bovine serum albumin protein adsorption. The highly porous structure of cuttlefish bone was preserved with a composite scaffold porosity of ~78%. A compressive strength of ~1.4 MPa makes the obtained composite scaffolds appropriate for non-load-bearing applications. Cytocompatibility assessment by an MTT assay of human mesenchymal stem cells revealed the non-cytotoxicity of the obtained scaffolds.  相似文献   
996.
The WHO European Region has the lowest exclusive breastfeeding (EBF) rates at 6 months in the world. In Austria, 55.5% of infants are EBF at the age of one week, although breastfeeding initiation is 97.5%. The study was conducted in 2019/2020 and considered 1214 mothers of legal age, who received four online questionnaires during their child’s first year of life. The influence of different variables on total/exclusive breastfeeding duration were analysed by using a Cox model (Extension of the Cox Proportional Hazards Model) with time-dependent covariates. Multivariate analyses showed a significant influence of maternal BMI, lifestyle factors, such as smoking, and breastfeeding support on total breastfeeding duration. Remarkable differences in the median duration of any breastfeeding were found for breastfeeding support, where mothers breastfed twice as long. Support came primarily from hospital staff, the midwife and the partner. A higher monthly household net income, delivery in a baby-friendly certified hospital (BFH) and breastfeeding support were associated with a longer EBF duration. Obese mothers started feeding infant formula earlier and had a higher risk of early weaning. The results offer valuable insights into the importance of breastfeeding-friendly structures such as BFHs, a focus on breastfeeding aftercare and support of the mother to promote and protect breastfeeding.  相似文献   
997.
Stephen AE  Milas M  Garner CN  Wagner KE  Siperstein AE 《Surgery》2005,138(6):1143-50; discussion 1150-1
BACKGROUND: This study investigates the utility of ultrasound guided parathyroid fine needle aspiration (FNA) as a localizing technique in patients with hyperparathyroidism (HPT) undergoing re-operative neck surgery or with unusually appearing or ectopically located glands. METHODS: Selected patients with HPT underwent surgeon-performed FNA with ultrasound guidance. Aspirate contents were sent for cytology and parathyroid hormone (PTH) levels. All patients subsequently underwent parathyroid exploration. RESULTS: 54 patients underwent 57 ultrasound guided parathyroid biopsies. Indications for FNA included prior parathyroid (n = 29), thyroid (n = 11), or other neck surgery (n = 2), or unusual parathyroid appearance or location (n = 12). A true positive was defined as a site where the PTH aspirate was >40 pg/mL and a hypercellular gland was removed at surgery. Based on this, there were 44 true positives, 10 true negatives, and 3 false negatives; there were no false positives. The median PTH level in positive aspirates was 11,665 pg/mL. Cytology was primarily helpful in excluding other diagnoses. CONCLUSION: Ultrasound guided FNA is a highly specific localization test for parathyroid tumors. This procedure can be successfully performed by surgeons in the office setting and is extremely valuable for directing parathyroid exploration in challenging cases. We recommend incorporating ultrasound and FNA as a pre-operative localization strategy for selected patients with HPT.  相似文献   
998.
Arterial stiffness, a significant prognostic factor of cardiovascular disease, may be affected by dietary factors. Research on the effects of oral vitamin supplements on arterial stiffness and/or endothelial function has produced controversial results. Therefore, the aim of this network meta-analysis was to comparatively assess the effect of different types of oral vitamin supplements on arterial stiffness in the adult population. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for randomized controlled trials from their inception to 30 September 2021. A network meta-analysis using a frequentist perspective was conducted to assess the effects of different types of oral vitamin supplements on arterial stiffness, as determined by pulse wave velocity. In total, 22 studies were included, with a total of 1318 participants in the intervention group and 1115 participants in the placebo group. The included studies were listed in an ad hoc table describing direct and indirect comparisons of the different types of vitamins. Our findings showed that, in both pairwise comparison and frequentist network meta-analysis, the different types of oral vitamin supplements did not show statistically significant effects on arterial stiffness. However, when oral vitamin supplementation was longer than 12 weeks, vitamin D3 showed a significant reduction in arterial stiffness, compared with the placebo (ES: −0.15; 95% CI: −0.30, −0.00; −60.0% m/s) and vitamin D2 (ES: −0.25; 95% CI: −0.48, −0.02, −52.0% m/s). In summary, our study confirms that oral vitamin D3 supplementation for more than 12 weeks could be an effective approach to reduce arterial stiffness and could be considered a useful approach to improve vascular health in patients at high risk of cardiovascular disease.  相似文献   
999.
Radial glia-like cells in the hypothalamus and dorsal vagal complex are neural precursors (NPs) located near subventricular organs: median eminence and area postrema, respectively. Their strategic position can detect blood-borne nutrients, hormones, and mitogenic signals. Hypothalamic NPs increase their proliferation with a mechanism that involves hemichannel (HC) activity. NPs can originate new neurons in response to a short-term high-fat diet as a compensatory mechanism. The effects of high carbohydrate Western diets on adult neurogenesis are unknown. Although sugars are usually consumed as sucrose, more free fructose is now incorporated into food items. Here, we studied the proliferation of both types of NPs in Sprague Dawley rats exposed to a short-term high sucrose diet (HSD) and a control diet. In tanycyte cultures, we evaluated the effects of glucose and fructose and a mix of both hexoses on HC activity. In rats fed an HSD, we observed an increase in the proliferative state of both precursors. Glucose, either in the presence or absence of fructose, but not fructose alone, induced in vitro HC activity. These results should broaden the understanding of the nutrient monitoring capacity of NPs in reacting to changes in feeding behavior, specifically to high sugar western diets.  相似文献   
1000.
In this article the method of Work Discussion is introduced as an instrument for improving the capacity for mentalization. The authors refer to a vocational training project with early child care teachers in kindergartens and a short case study is presented. The authors use this project to outline how work discussion was used to reflect on professional practice and the goals pursued by applying this method in the course of vocational training. The concept of ‘mentalization’ is defined and the paper discusses whether and how using work discussion can contribute to stimulating, developing or enhancing the early child care teachers’ capacity mentalize.  相似文献   
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