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71.
Several studies have demonstrated that selenium (Se) at low concentrations is beneficial, whereas high Se concentrations can induce toxicity. Controlling Se uptake, metabolism, translocation and accumulation in plants is important to decrease potential health risks and helping to select proper biofortification methods to improve the nutritional content of plant-based foods. The uptake and distribution of Se, changes in Se content, and effects of various concentrations of Se in two forms (sodium selenite and sodium selenate) on sunflower and maize plants were measured in nutrient solution experiments. Results revealed the Se content in shoots and roots of both sunflower and maize plants significantly increased as the Se level increased. In this study, the highest exposure concentrations (30 and 90 mg/L, respectively) caused toxicity in both sunflower and maize. While both Se forms damaged and inhibited plant growth, each behaved differently, as toxicity due to selenite was observed more than in the selenate treatments. Sunflower demonstrated a high Se accumulation capacity, with higher translocation of selenate from roots to shoots compared with selenite. Since in seleniferous soils, a high change in plants’ capability exists to uptake Se from these soils and also most of the cultivated crop plants have a bit tolerance to high Se levels, distinction of plants with different Se tolerance is important. This study has tried to discuss about it.  相似文献   
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Objective: This study was designed to assess the effects of omega-3 fatty acid supplementation on inflammatory factors, biomarkers of oxidative stress, and pregnancy outcomes among pregnant women with gestational diabetes (GDM).

Methods: This randomized, double-blind, placebo-controlled clinical trial was performed among 56 women with GDM. Subjects were randomly selected to receive either 1000?mg omega-3 fatty acid supplements (containing 180?mg eicosapentaenoic acid and 120?mg docosahexanoic acid) (n?=?27) or a placebo (n?=?27) for 6 weeks. Fasting blood samples were taken at study baseline and after 6 weeks of intervention to quantify biochemical variables. Newborn’s weight, height, head circumference, Apgar score, and hyperbilirubinemia were determined.

Results: At the end of the 6 weeks, taking omega-3 fatty acid significantly decreased serum high-sensitivity C-reactive protein (hs-CRP) (change from baseline: ?245.1?±?1570.5 versus?+?913.9?±?2329.4?ng/mL, p?=?0.03) and plasma malondialdehyde (MDA) concentrations (?0.4?±?1.3 versus?+?0.6±2.3, p?=?0.04) compared with the placebo. Supplementation with omega-3 had a low incidence of hyperbilirubinemiain newborns (7.7% versus 33.3%, p?=?0.02) and decreased newborns’ hospitalization rate (7.7% versus 33.3%, p?=?0.02).

Conclusions: Taken together, omega-3 fatty acid supplementation in GDM women had beneficial effects on maternal serum hs-CRP, plasma MDA levels, incidence of newborn’s hyperbilirubinemia, and hospitalization.  相似文献   
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Introduction  The timed barium study (TBS) is used to assess esophageal emptying in patients with achalasia. Improvement in emptying correlates with outcome after endoscopic therapy, but the results of the TBS have been variable after myotomy. Our aim was to evaluate a new method for assessing improvement in emptying after myotomy. Methods  A TBS was performed before and 3–6 months after myotomy in 30 patients. Emptying was assessed by measuring the percent difference in area of the barium column on films obtained 1 and 5 min after ingesting 150 ml of barium. Initial esophageal clearance was also assessed by comparing the area of the barium column on 1-min images obtained before and after therapy. Both measures were compared to clinical outcome. Results  After myotomy, 21 patients (70%) had no symptoms, four (13%) had mild, and five (17%) had moderate/severe symptoms. Using the standard method, esophageal emptying before and after surgery were not significantly different (25% vs. 37%; p = 0.22) and did not correlate with clinical outcome. In contrast, initial esophageal clearance improved significantly (median 81%) and correlated with clinical outcome. Conclusion  Esophageal emptying measured by the standard method is not useful to assess outcome after myotomy. However, initial esophageal clearance correlates well with clinical outcome. Previous presentations: 49th SSAT Annual Meeting at Digestive Disease Week, San Diego, 2008 and 23rd Annual SSAT Residents and Fellows Research Conference, San Diego, 2008  相似文献   
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Bladder cancer (BC) is known as a prevalent genitourinary malignancy and has a significant mortality rate worldwide. Despite recent therapeutic approaches, the recurrence rate is high, highlighting the need for a new strategy to reduce the BC cell progression. Quercetin, a flavonoid compound, demonstrated promising anticancer properties and could be used in the management of various malignancies such as BC. This comprehensive review summarized quercetin's cellular and molecular mechanisms underlying anticancer activities. The study's findings indicated that quercetin prevents the proliferation of the human BC cell line, promotes apoptosis of BIU-87 cells, reduces the expression of p-P70S6K, and induces apoptosis by p-AMPK. Moreover, quercetin restricts tumor growth through the AMPK/mTOR cascade and prevents colony formation of human BC cells by triggering DNA damage. Studying this review article will help researchers better understand quercetin's functional role in the prevention and treatment of BC.  相似文献   
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Background: Keratoconus is a connective tissue-related eye disease with unknown etiology that causes the loss of visual acuity. Lysyl oxidase (LOX) is an amine oxidase that catalyzes the covalent cross-link of collagens and elastin in the extracellular environment, thus determining the mechanical properties of connective tissue. The current study aimed to investigate the possible associations between two LOX polymorphisms, rs1800449 and rs2288393, and susceptibility to keratoconus.

Methods: A total of 262 Iranian subjects including 112 patients with keratoconus and 150 healthy individuals as controls were recruited. Genotyping for the LOX variants was performed using allele-specific PCR.

Results: A significant difference was found between two groups regarding allelic and genotyping distribution of LOX polymorphism at position rs1800449 G>A. The frequency of AA and GA?+?AA genotypes were increased in patients compared to controls (17% versus 8% and 62.5% versus 50%, respectively), showing a statistically significant difference (OR?=?2.827, 95% CI: 1.251–6.391, p?=?0.012). The A allele was associated with an increased risk for keratoconus, with the frequency of 39.9% and 29% in patients and controls, respectively (OR?=?1.614, 95% CI: 1.119–2.326, p?=?0.011). Furthermore, the haplotype analysis revealed that the rs1800449G/rs2288393C is a protective factor against keratoconus (OR?=?0.425, 95% CI?=?0.296–0.609, p?=?0.001). Conversely, the +473A/rs2288393C (OR?=?3.703, 95% CI?=?2.230–6.149, p?=?0.001) and +473G/rs2288393G (OR?=?15.48, 95% CI?=?3.805–63.03, p?=?0.001) haplotypes were identified as risk factors for keratoconus.

Conclusion: Our study demonstrated that the LOX rs1800449 genotypes (AA and GA?+?AA) and allele (A) appears to confer risk for susceptibility to keratoconus.  相似文献   
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