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The association between obesity and vitamin A has been studied. Some studies point to the anti-obesity activity related to this vitamin, carotenoids with provitamin A activity, and carotenoid conversion products. This performance has been evaluated in respect of adipogenesis, metabolic activity, oxidation processes, secretory function, and oxidative stress modulation, showing a new property attributed to vitamin A in preventing and treating obesity. However, vitamin A and its precursors are highly sensitive and easily degraded when subjected to heat, the presence of light, and oxygen, in addition to losses related to the processes of digestion and absorption. In this context, encapsulation presents itself as an alternative capable of increasing vitamin A’s stability in the face of unfavorable conditions in the environment, which can reduce its functionality. Considering that vitamin A’s status shows a strong correlation with obesity and is an innovative theme, this article addresses the associations between vitamin A’s consumption and its precursors, encapsulated or not, and its physiological effects on obesity. The present narrative review points out those recent studies that demonstrate that vitamin A and its encapsulated precursors have the most preserved functionality, which guarantees better effects on obesity therapy.  相似文献   
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Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in...  相似文献   
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Background

Non-alcoholic fatty liver disease (NAFLD) is a common, severe disease in obese patients. However, NAFLD is usually underestimated by ultrasonography. Liver biopsy is not routinely done in bariatric surgery or during the follow-up. This study therefore examined the correlation between metabolic syndrome and NAFLD in morbidly obese patients based on an assessment using transient hepatic elastography (THE).

Material and Methods

This study involved 50 female patients in the pre-operative phase for bariatric surgery. Before surgery, we collected clinical, laboratory, and anthropometric variables. THE measurements were obtained using a FibroScan® device (Echosens, Paris, France), and steatosis was quantified using Controlled Attenuation Parameter software (CAP). Statistical analyses were done using linear correlation and the Kruskal-Wallis test.

Results

The mean of THE and CAP values were 7.56?±?4.78 kPa and 279.94?±?45.69 dB/m, respectively, and there was a significant linear correlation between the two measurements (r?=?0.651; p?<?0.001). The numbers of metabolic syndrome parameters did not influence the THE (p?=?0.436) or CAP (p?=?0.422) values. HbA1c and HOMA-IR showed a strong linear correlation with CAP (r?=?0.643, p?=?0.013 and r?=?0.668, p?=?0.009, respectively) and a tendency to some linear correlation with THE (r?=?0.500, p?=?0.05 and r?=?0.500, p?=?0.002, respectively).

Conclusion

Morbidly obese women submitted to FibroScan® presented a high prevalence of severe steatosis and advanced fibrosis in our sample. Insulin resistance parameters were correlated with steatosis, but less with fibrosis.
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BACKGROUND: Nitric oxide is an important regulator of various biological activities in human physiology, and it has been studied in the physiopathology of asthma, especially in exhaled air. OBJECTIVE: We studied the presence of NO in sera of patients with distinct degrees of asthma severity in order to determine a parameter of diagnosis and control of efficacious treatment. METHODS: We determined the presence of NO based upon the Griess reaction in the sera of 124 donors--34 controls and 90 asthmatic subjects. RESULTS: Asthmatic patients presented higher levels of nitric oxide in peripheral blood (56.54 +/- 33.37) compared to the control group (3.06 +/- 4.48). A statistically significant difference (p < 0.0001) between the nitric oxide sera levels from the two groups was demonstrated. CONCLUSION: This study demonstrates that nitric oxide sera levels can be used as an additional inflammatory marker in asthma, especially as an auxiliary diagnostic method in children where NO exhaled air analysis is difficult.  相似文献   
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ObjectiveTo assess and compare the effects produced in the maxillary dental arch by means of Connecticut intrusion arch (CIA) with or without a cinch back on the distal end of the tube of the first molars.Materials and MethodsThis study included 44 patients with a mean age of 13.1 ± 1.8 years treated for deep bite with a CIA randomly divided into two groups: group 1 (G1), 22 patients with initial mean age of 12.72 ± 1.74 years treated with the CIA in the upper arch without a cinch back on the distal surface of the tube of the first molars, and group 2 (G2), 22 patients with an initial mean age of 13.67 ± 2.03 years treated with the CIA with a cinch back. Lateral cephalograms were available before treatment (T1) and after intrusion of maxillary incisors (T2). The mean treatment period was 5.5 ± 1.45 months. Intragroup and intergroup changes in the maxillary incisor and molar positions were analyzed by paired and independent t-tests associated with the Holm-Bonferroni correction method for multiple comparisons (P < .05).ResultsThere were significant differences between groups in terms of maxillary incisor displacement. The maxillary incisors flared labially (2.17°) and proclined (1.68 mm) in group 1, whereas a palatal inclination (−1.99°) and retroclination (−1.13 mm) was observed in group 2. No significant differences were found for the molar positions between the groups.ConclusionsThe presence or absence of a distal bend in CIA affects incisor tipping and proclination during intrusion mechanics.  相似文献   
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