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211.
Gordh T  Sharma HS  Azizi M  Alm P  Westman J 《Amino acids》2000,19(1):373-381
The influence of carbon monoxide (CO) on chronic spinal nerve lesion induced spinal cord neurodegeneration was examined using immunohistochemical expression of the constitutive isoform of its synthesising enzyme, hemeoxygenase-2 (HO-2) in a rat model. Spinal nerve lesion at L-5 and L-6 level was produced according to the Chung model of neuropathic pain and rats were allowed to survive for 8 weeks. Sham operated rats, in which the spinal nerves were exposed but not ligated, served as controls. Ligation of spinal nerves in rats resulted in an upregulation of HO-2 expression which was most pronounced in the ipsilateral gray matter of the spinal cord compared to the contralateral side. In these rats, morphological investigations showed distorted neurons, membrane disruption, synaptic damage and myelin vesiculation. Sham operated rats did not show an upregulation of HO-2 expression and the structural changes in the spinal cord were absent. These observations strongly suggest that spinal nerve lesion is associated with an increased production of CO which is somehow contributing to the neurodegenerative changes in the spinal cord, not reported earlier.  相似文献   
212.
Oxidative stress in obesity leads to insulin resistance in type 2 diabetes. Some selenoproteins possess antioxidant properties, suggesting that selenium (Se) may protect against type 2 diabetes; however, evidence from epidemiological studies is contradictory. We hypothesized that Se status before supplementation (baseline) contributes to the supplementation outcome. This study aimed to clarify the influence of baseline Se status on the effect of Se supplementation on the diabetic condition. Six-week-old KKAy mice were fed a diet without supplemental Se or with 0.1 ppm Se in the form of l-selenomethionine (SeM) for 2 weeks to create low-Se and sufficient-Se baseline statuses, respectively. For the next 4 weeks, low-Se mice were given a SeM (0.5 ppm Se)-supplemented diet, and sufficient-Se mice were given either a SeM (0.5 ppm Se)- or sodium selenite (0.5 ppm Se)-supplemented diet; control groups continued on baseline diets. Serum Se concentrations, glutathione peroxidase (GPx) activities, adiponectin levels, glucose tolerance, and insulin sensitivity were analyzed. All mice became diabetic during the 2-week baseline induction period. At the end of the supplementation period, Se-receiving groups demonstrated significantly higher Se concentrations and GPx activities than their respective controls. Sufficient-Se mice receiving SeM had lower blood glucose levels and better insulin sensitivity than control and sodium selenite-receiving mice, whereas low-Se mice receiving SeM showed no such improvements compared with their controls. Our results suggest that Se supplementation in the form of SeM may help prevent type 2 diabetes aggravation in people taking the 55 μg/day Se recommended dietary allowance.  相似文献   
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Aptamers are DNA or RNA single-stranded molecules that bind specifically to target molecules with high affinity. Function of nucleic acid aptamers is based on organized tertiary structure of them that is related to primary sequence, length of nucleic acid molecule, and environmental conditions. Herein, a localized surface plasmon resonance (LSPR) nanobioprobe has been developed based on specific aptamer-conjugated gold nanoparticles for rapid detection of methamphetamine. Detection of methamphetamine was studied via monitoring the gold nanoparticles (GNPs) LSPR band alterations in the presence of different concentrations. The covalent conjugation has been confirmed with FT-IR spectroscopy, and size alterations of gold nanoparticles before and after the conjugation state were monitored using dynamic light scattering (DLS) technique. The results show high affinity of aptamer to methamphetamine. Moreover, the results show conjugated aptamer with GNP in different concentrations of methamphetamine that contribute to color changes that is visible with unaided eye. Also, 14 nm LSPR shift was seen after conjugation of aptamer with GNP. Nanoparticle diameter after conjugation with aptamer was increased from 30 to 91 nm and decreased after incubation with methamphetamine (due to folding) from 91 to 84 nm. Detection limit of this designed nanoprobe is 500 nM. Plasmonic nanoparticle-based nanobioprobe is a new field for development of sensitive detection systems.

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216.
Etanercept is a soluble fusion protein of the tumor necrosis factor receptor (TNFR) extracellular domain, linked to an Fc part of IgG1. It possesses three N- and 13 O-glycosylation sites. Due to its complex structure, an analytical challenge is facing the development and approval of biosimilars. In the current study, physicochemical characterization using state-of-the-art analytics was performed to analyze intact and subunit masses, post-translational modifications (PTMs), higher order structure and potency of Etanercept originator Enbrel® and its biosimilar Altebrel? (AryoGen Pharmed) in accordance to critical quality attributes of biopharmaceuticals. Intact mass and subunit analysis revealed a size of about 126 kDa for both biologicals. Similar glycoprotein species for the complete monomer and the Fc domain of originator and follow-on product were observed, however, small differences in lysine variants and oxidation were found. N-Glycopeptide analysis with UHPLC-QTOF-MSE confirmed the N-glycosylation sites (N149, N171 and N317) as well as Fc-specific glycosylation on N317, and TNFR-specific highly sialylated glycans on N149 and N171 on both investigated products. Small quantitative variations in the N-glycan profile were detected, although the N-glycans were qualitatively similar. Four different O-glycopeptides bearing core 1-type glycans were detected. For both, N- and O-glycopeptide analysis, determination was achieved without prior cleavage of the sialic acid residues for the first time. In addition, ion mobility spectrometry data confirmed close similarity of higher-order structure of both biologics. Furthermore, a neutralization assay, investigating the impact of altered PTMs on potency, indicated that the differences within all batches are still in the acceptable range for biosimilarity.  相似文献   
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Specific learning disorder (SLD) can occur along with the problems of attention performance and be complicated by them. Recent studies have reported the positive effects of cognitive rehabilitation (CR) and neurofeedback (NFB) on sustained attention (SA) in SLD. Nevertheless, it has not yet been determinedwhat kind of treatment may be the most appropriate option for this disorder in terms of the different functions of cognitive status, especially SA. This preliminary study aimed to compare CR and NFB effects on SA among elementary school students with SLD using a randomized controlled clinical trial (RCT). Fifty- three eligible students with a DSM-5 SLD diagnosis, aged 7–10, were randomly allocated in NFB (n?=?18), CR (n?=?18), and control groups (n?=?17). All the participants were evaluated for SA by performing the continuous performance test (CPT) on the studied groups at the time of their inclusion in the study and 7 weeks after it. The intervention groups took part in 20 sessions of CR and 20 sessions of NFB. Conversely, the untreated group were evaluated without any intervention.15 boys and 30 girls in 3 groups completed the study (n?=?15 per group). The mean and standard deviation of participants’ age were (8.66?±?1.48) years, (8.40?±?1.73) years and (8.53?±?1.63) years in CR, NFB and untreated groups, respectively. The results showed significant differences between the groups based on the variables of the CPT test (p?<?0.05). Also, the significant effects of the variables represented the higher scores of the CR compared to the NFB group (p?<?0.001). This study provides einitial evidence that CR is more effective than NFB on SA improvement among students with SLD.  相似文献   
218.

Purpose

Studies indicate that milk intake is associated with insulin-like growth factor 1 (IGF-1) concentrations and height in childhood, whether milk and other dairy products promote puberty remains unclear. This study aimed to investigate influences of pre-pubertal intakes of milk, yogurt and cheese on menarcheal age in Tehranian girls. The associations of total dietary calcium (Ca), magnesium (Mg), and phosphorus (P) with menarcheal age were also examined.

Methods

This prospective study was conducted on 134 pre-pubertal girls, aged 4-12 years at baseline, who participated in the Tehran Lipid and Glucose Study (TLGS), and were followed for a median of 6.5 years. Dietary intakes were determined at initiation of the study using two non-consecutive 24-h dietary recalls and the age of menarche was documented during the follow-up. Logistic regression was used to calculate the risk of reaching menarche ≤ 12 years according to pre-pubertal levels of dairy or mineral intakes.

Results

The risk of earlier menarche was higher in girls with higher intakes of milk [OR: 2.28 (95% CI: 1.03–5.05)], Ca [OR: 3.20 (95%CI: 1.39–7.42)], Mg [OR: 2.43 (95% CI: 1.12–5.27)] and P [OR: 3.37 (95 % CI: 1.44–7.87) after controlling for energy and protein intake, interval between the age at study initiation and the age of menarche, and maternal age at menarche (Model 1). Girls in the middle tertile of cheese intakes had a lower risk of reaching menarche ≤ 12 years than those in the lowest tertile after controlling for covariates in model 1. These associations remained significant after further adjustment of BMI Z-score at baseline. The relationship of Ca, Mg, and P with menarche remained after further adjustment for height Z-score at baseline, whereas the association between milk and cheese intakes became non-significant.

Conclusions

Pre-pubertal intake of milk, but not cheese and yogurt, may hasten age at menarche.  相似文献   
219.
Molecular Biology Reports - Preeclampsia (PE) is a major complication of pregnancy and remains a leading cause of neonatal and maternal mortality worldwide. Several studies have revealed that the...  相似文献   
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