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The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO2/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency.  相似文献   
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Epidemiologic studies have demonstrated that trans fat intake increases the risk of some chronic diseases. We hypothesize that trans fat intake would increase the risk of cardiovascular disease and type 2 diabetes mellitus by changing the lipid profile in plasma, the secretion of adipokines in adipose tissue, and the insulin sensitivity. Accordingly, the major objective of present study was to investigate the effect of dietary intake of trans fat on lipid profile, insulin sensitivity, and adipokine levels in plasma. Two groups of Wistar rats were fed a diet containing 4.5% trans fat or a control diet containing no trans fat for 16 weeks. Fasting glucose level was monitored every 2 weeks. At the end of feeding experiment, blood, heart, kidney, liver, omental adipose tissue, and semitendinosus muscle were collected. The trans fat content in organs, lipid profile, adipokine, insulin, and glucose levels in plasma were analyzed. The trans fat content in adipose tissue, heart, kidney, liver, and muscle of rats fed trans fat were 169.9, 0.6, 1.2, 1.7, and 2.5 mg/g samples, respectively. The trans fat content in these organs contributed to 15.9%, 1.2%, 2.3%, 4.3%, and 6.1% of the total fat, respectively. The plasma glucose level, insulin level, and insulin sensitivity index were not significantly different between the trans fat and control groups. The results indicated that trans fat intake might not be related to insulin resistance. However, lipid profile and plasma adipokine levels were significantly changed after trans fat feeding. The trans fat fed group showed significantly lower total cholesterol and high-density lipoprotein cholesterol levels than the control group. The decreased high-density lipoprotein cholesterol level may indicate the detrimental effect of trans fat intake on lipid profile. Adiponectin and resistin levels were significantly higher in the trans fat group than the control group. Leptin levels were significantly lower in the trans fat group than the control group. The results indicated that dietary intake of trans fat can significantly change the adipokine levels, but the possible links between adipokine level change caused by trans fat intake and metabolic effects of this change need further investigations.  相似文献   
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BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo.  相似文献   
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Forty eight patients with extensive occupational exposure to pneumatic grinding tools were evaluated at a university sponsored occupational health clinic. All patients were interviewed and examined by a physician and assessed neurologically with standard clinical, functional motor, quantitative vibrotactile, and electrodiagnostic tests. Sensorineural symptoms were nearly universal; 47 patients (98%) reported numbness and tingling of the hands and fingers. Among clinical tests, two point discrimination and 30 Hz vibration perception were most frequently abnormal. In order to evaluate associations between quantitative test results and sensorineural symptoms, patients were stratified into two groups of symptom severity according to a consensus sensorineural staging system. The tests that discriminated best between the groups of more and less symptomatic patients were hand strength dynamometry, and vibrotactile thresholds. Age standardised 120 Hz vibrotactile thresholds were significantly raised in digit II in 41% of hand measurements. Nerve conduction studies were neither significantly different between more and less symptomatic groups nor correlated with clinical and quantitative sensory tests. Twenty five per cent of the patients had slowing of sensory conduction velocities in the median nerve at the wrist (less than 48 m/s). Of this subset of patients only two showed abnormal slowing of the median nerve distal to the wrist, but half also showed ulnar nerve slowing (less than 47 m/s).This observation highlights the difficulty of differentiating median nerve entrapment from diffuse distal neuropathy in workers exposed to vibration and points to the need for concomitant quantitative sensory and functional motor assessment.  相似文献   
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