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BackgroundPollinosis from Amaranthus retroflexus pollen is a common cause of respiratory allergy in Iran with a high positive rate (68.8%) among Iranian allergic patients. The aim of the present study was to evaluate the allergenicity of the A. retroflexus pollen profilin.MethodsUsing sera from twelve patients allergic to A. retroflexus pollen, IgE-binding proteins from the A. retroflexus pollen extract was identified by immunoblotting. The cDNA of A. retroflexus pollen profilin was amplified, then cloned into the pET-21b (+) vector, expressed in Escherichia coli, and finally purified by metal affinity chromatography. The IgE-binding capacity of the recombinant protein was then analyzed by the ELISA, immunoblotting, and inhibition assays, as well as by the skin prick test (SPT).ResultsImmunoblotting results indicated a 14.6 kDa protein with IgE-reactivity to 33% (4/12) among A. retroflexus pollen-allergic patients. Nucleotide sequencing of the cDNA revealed an open reading frame of 399 bp encoding for 133 amino acid residues which was belonged to the profilin family and designated as Ama r 2. A recombinant Ama r 2 (rAma r 2) was then produced in E. coli as a soluble protein which showed a strong IgEreactivity via ELISA confirmed by the SPT. Inhibition experiments revealed high IgE cross-reactivities with the profilins from other plants.ConclusionsThe profilin from the A. retroflexus pollen, Ama r 2, was firstly identified as an allergen. Moreover, rAma r 2 was produced in E. coli as a soluble immunoreactive protein with an IgE-reactivity similar to that of its natural counterpart.  相似文献   
994.
The observed increased risks of gastric cancer among first-generation immigrants compared to those in Swedes suggest the role of childhood environmental exposure in the risk of this disease.  相似文献   
995.
Increases in antioxidant defense capacity have been associated with increases in the health and life span of calorie restricted animals. Emory mice develop late-life cataract, a lesion associated with oxidative damage and loss of lens glutathione (GSH). The effect of calorie restriction on GSH in liver and kidney in this model has not been explored. GSH and oxidized GSH (GSSG) were measured by HPLC in liver and kidney of Emory mice fed a control diet (C; 85% calories of ad-lib fed mice) or 60% calorie intake of C (R; 40% calorie restriction relative to C mice) for up to 22 mo age. Liver GSH concentration increased significantly in C and R mice from 4.5 to 12 mo old with no difference observed between the two groups. At 22 mo of age, liver GSH was lower than that of 12 mo old in both groups. As compared with GSH at 12 mo old, this decrease was almost twice as greater in C (70%, p=0.001) than in R mice (36%, p=0.02), so that R mice had a significantly higher concentration of GSH in liver than C mice at 22 mo of age (R = 32.8+5.1, C= 22.1+8.3 imol GSH/g protein, p<0.01). Liver GSSG was similar in C and R mice at 12 mo of age (4.45+1.35 vs. 4.75+1.83 imol GSSG/g protein), but increased in R mice at 22 mo (R=5:43±1.48; C=3.22±1.02, p<0.01). Therefore, at 22 mo old, total liver glutathione (GSH+GSSG) was higher in R than in C mice. There was no significant difference in GSH, GSSG and total GSH in kidney from C and R mice at these ages. Thus, calorie restriction reduces the age-related loss of GSH antioxidant capacity in liver but not kidney of Emory mice.  相似文献   
996.
Bisphenol A (BPA), an estrogenic compound, is used in manufacture of polycarbonate plastics and epoxy resins. Curcumin, the active ingredient of turmeric, is a potent protective compound against cardiac diseases. In this study the protective effect of nanomicelle curcumin on BPA‐induced subchronic cardiotoxicity in rats was evaluated. Rats were divided into 6 groups including control, nanomicelle curcumin (50 mg/kg, gavage), BPA (50 mg/kg, gavage), nanomicelle curcumin (10, 25, and 50 mg/kg) plus BPA. The treatments were continued for 4 weeks. Results revealed that BPA significantly induced histophatological injuries including focal lymphatic inflammation, nuclear degenerative changes and cytoplasmic vacuolation, increased body weight, systolic and diastolic blood pressures, malondialdehyde and Creatine phosphokinase‐MB level and decreased glutathione content in comparison with control group. In addition, in electrocardiographic graph, RR, QT, and PQ intervals were increased by BPA. Western blot analysis showed that BPA up‐regulated phosphorylated p38 (p38‐mitogen‐activated protein kinase) and JNK (c‐jun NH2 terminal kinases), while down‐regulated phosphorylated AKT (Protein Kinase B) and ERK1/2 (extracellular signal‐regulated protein kinases 1 and 2). However, nanomicelle curcumin (50 mg/kg) significantly improved these toxic effects of BPA in rat heart tissue. The results provide evidence that nanomicelle curcumin showed preventive effects on subchronic exposure to BPA induced toxicity in the heart tissue in rats.  相似文献   
997.
Patients with type 2 diabetes often present with cardiovascular complications; however, it is not clear how diabetes promotes cardiac dysfunction. In murine models, deletion of the gene encoding aryl hydrocarbon nuclear translocator (ARNT, also known as HIF1β) in the liver or pancreas leads to a diabetic phenotype; however, the role of ARNT in cardiac metabolism is unknown. Here, we determined that cardiac-specific deletion of Arnt in adult mice results in rapid development of cardiomyopathy (CM) that is characterized by accumulation of lipid droplets. Compared with hearts from ARNT-expressing mice, ex vivo analysis of ARNT-deficient hearts revealed a 2-fold increase in fatty acid (FA) oxidation as well as a substantial increase in the expression of PPARα and its target genes. Furthermore, deletion of both Arnt and Ppara preserved cardiac function, improved survival, and completely reversed the FA accumulation phenotype, indicating that PPARα mediates the detrimental effects of Arnt deletion in the heart. Finally, we determined that ARNT directly regulates Ppara expression by binding to its promoter and forming a complex with HIF2α. Together, these findings suggest that ARNT is a critical regulator of myocardial FA metabolism and that its deletion leads to CM and an increase in triglyceride accumulation through PPARα.  相似文献   
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Background  

Pancreatic fistula is a significant problem for patients undergoing distal pancreatectomy with fistula rates up to 61%. Fistulas lead to substantial morbidity. The study objective was to compare radiofrequency dissector closure with traditional stump closure for distal pancreatectomy.  相似文献   
1000.
Our aim was to determine if zoledronic acid (ZA) changes 45Ca pharmacokinetics and bone microstructure in irradiated, ovary-intact (I) and irradiated, ovariectomized mice (OVX), two groups with different patterns of skeletal damage. The hind limbs of I and OVX BALB/c mice received a single 16-Gy radiation dose, simulating pre- and postmenopausal female cancer patients undergoing radiation treatment. All I and OVX mice were radiolabeled with 15 μCi 45Ca. Mice were treated with or without a 0.5 mg/kg injection of ZA. The time course of bone mineral remodeling was evaluated using a fecal 45Ca assay, measured by liquid scintillation. A group of nonirradiated, intact mice were used for the longitudinal evaluation of 45Ca biodistribution. Distal femur bone histomorphometric parameters were measured using microCT at 50 days post–ZA intervention. Most 45Ca was incorporated into the skeleton and eliminated from the soft tissues within 3–5 days postirradiation, attaining a steady state of excretion at 25–30 days. ZA intervention in both groups resulted in a rapid decrease in fecal 45Ca excretion. There was a significant difference in 45Ca excretion in the OVX ± ZA (P = 0.005) group but not in the I ± ZA (P = 0.655) group. The rate of excretion of fecal 45Ca was slower in the OVX + ZA compared to the I + ZA group (P = 0.064). 45Ca assay is useful to monitor the time course of bone mineral remodeling after an antiresorptive intervention in irradiated mice, providing a basis to investigate bone effects of cancer therapy protocols. For equivalent doses of ZA, recovery may depend on the nature and degree of skeletal damage.  相似文献   
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