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61.
Age and ApoE genotype interaction in Alzheimer's disease: an FDG-PET study   总被引:1,自引:0,他引:1  
Previous positron emission tomography (PET) studies with fluorodeoxglucose (FDG) as tracer in healthy elders showed that the epsilon4 allele of the apolipoprotein E (ApoE) gene is disruptive to cerebral glucose metabolism (rCMRglu), possibly through the interaction with the aging process. The present study was aimed at assessing whether this interaction occurs in patients with Alzheimer's disease (AD). Eight-six AD patients, including 40 ApoE4 carriers and 46 non-carriers, underwent (18)F-FDG PET scanning at rest. ApoE groups were comparable for age, gender, age at onset and disease duration. SPM'99 was used to assess rCMRGlu correlations with age, differences between ApoE groups and ApoE by age interaction, correcting for disease severity. Results were reported at P<0.001, uncorrected. Correlations between age and rCMRGlu confirmed the well-known negative relationship for both groups. Lower rCMRGlu was found within the frontal and cingulate areas for ApoE4 carriers as compared with the non-carriers. Additionally, a significant ApoE by age interaction was detected in the frontal and anterior cingulate cortex, with the ApoE4 carriers having a steeper regression slope with respect to the non-carriers. These results indicate that age-related regional rCMRglu decreases within the frontal and anterior cingulate areas may be more severe in AD patients carrying the ApoE4 allele.  相似文献   
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International Ophthalmology - The advancement of tissue engineering and cell therapy research has resulted in innovative therapeutic options for patients with corneal endothelial diseases. The aim...  相似文献   
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Abstract

Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants which occur in considerable amounts in the environment and food. In this study, a meta-analysis study was conducted on PAHs concentrations in fish in different parts of the world. The results showed that the PAHs were observed and quantified in fish in the most considered studies. The maximum and minimum concentration of PAHs was found in Cynoglossus Bilineatus fish of Persian Gulf (3970?ng/kg) and Cyprinus Carpio fish of Caspian Sea (0.004?ng/kg), respectively. These values are below the maximum value currently allowed by European Union regulations (12.0?μg/kg wet weight).  相似文献   
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Von Willebrand disease (VWD), the most common genetic bleeding disorder, is caused by defects in Von Willebrand factor (VWF). Quantitative deficiencies of the protein lead to either VWD type3, the severe form of the disease or VWD type1 with milder clinical manifestation. Null alleles are the most common mutations in VWF gene causing type3. However, some of these mutations are not translated into the protein and are selectively degraded at mRNA level by nonsense-mediated decay (NMD) pathway. Here, we have studied a large VWD type3 pedigree with a premature termination codon (PTC) causing insertion mutation (c.7674-7675insC) in VWF exon 45. We further investigated the impact of the mutation on the VWF mRNA expression using a quantitative Real-time PCR assay and cDNA sequencing. The relative expression of the gene was significantly decreased in the patients' platelets (Mean ratio=0.03 (0.01-0.05), p=0.001) compared to their normal relatives. The heterozygote carriers of the mutation had lower than normal VWF mRNA levels (Mean ratio=0.62 (0.29-0.91), p=0.006). Direct sequencing of exon 45 on the platelet-derived cDNA in the carriers revealed only the wild-type allele confirming the decay of the mutation carrying allele. In conclusion, quantitative analysis of VWF gene expression showed that c.7674-7675insC mutation in VWF gene resulted in degradation of VWF mRNA via NMD. This pathway might play an important role in the pathogenesis of VWD characterized by quantitative deficiency of VWF due to reduced mRNA levels.  相似文献   
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Transforming growth factor beta‐3 (TGF‐β3) has been shown to decrease scar formation after scheduled topical applications to the cutaneous wounds. This study aimed to continuously deliver TGF‐β3, during the early phase of wound healing, by engineering a dermal equivalent (DE) using TGF‐β3 expressing bone marrow stromal cells (BM‐SCs) and human dehydrated amniotic membrane (hDAM). To engineer a DE, rat BM‐SCs were seeded on the hDAM and TGF‐β3 was transiently transfected into the BM‐SCs using a plasmid vector. Pieces of the dermal equivalent were transplanted onto the full‐thickness excisional skin wounds in rats. The process of wound healing was assessed by image analysis, Manchester Scar Scale (MSS), and histopathological studies 7, 14, 21, and 85 days after the excision. The results confirmed accurate construction of recombinant pcDNA3.1‐TGF‐β3 expression system and showed that the transfected BM‐SCs seeded on hDAM expressed TGF‐β3 mRNA and protein from day 3 through day 7 after transfection. After implantation of the DE, contraction of the wounds was measured from day 7 through 21 and analyzed by linear regression, which revealed that the rate of wound contraction in all experimental groups was similar. Histologic evaluation demonstrated that transfected BM‐SCs decreased retention and recruitment of the cells during the early stage of wound healing, decreased the formation of vascular structures and led to formation of uniformly parallel collagen bundles. MSS scores showed that TGF‐β3 secreting cells significantly improved the cosmetic appearance of the healed skin and decreased the scar formation. From these results, it could be concluded that transient secretion of TGF‐β3, during the early phase of healing, by BM‐SCs seeded on hDAM can improve the cosmetic appearance of the scar in cutaneous wounds without negatively affecting the process of wound repair.  相似文献   
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Sleep disorders are a common problem during pregnancy and may affect quality of life. This study aimed to determine the status of sleep quality and its relationship with quality of life in Iranian pregnant women. This cross‐sectional study was conducted on 565 women recruited using 2‐stage cluster sampling methods. Data were collected using sociodemographic characteristics; quality of life; and Pittsburgh sleep quality questionnaire between March and May 2015. About 6% of the women had a sleep disorder. There were significant correlations between quality of life and total score of sleep quality, subdomains of habitual sleep efficiency, sleep disturbance, and daytime dysfunction. Paying attention to the sleep quality as an effective factor of quality of life can promote sleep quality and hence quality of life of pregnant women.  相似文献   
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The purpose of this study was to investigate the effect of educational text messages, based on the health belief model, on osteoporosis preventive behaviors among women aged 30–45 years. This trial was conducted on 121 women from November until September 2017 in Shabestar, Iran. The intervention group received a daily educational text message about osteoporosis for one month, and the control group received educational text messages on frequently occurring cancers in women. Two months after the training, data were collected using the osteoporosis health belief scale, a food frequency questionnaire and the International Physical Activity Questionnaire. No significant differences were observed at baseline between the two groups, except for the perceived benefits construct. After the intervention, controlling for baseline score and adjusting for educational level, a statistically significant difference was observed between the two groups in HBM structures and nutrition performance, while no significant difference was observed in physical activity between the two groups. This study showed that educational text messages can be effective in increasing awareness, perceived susceptibility and severity, and nutritional behavior change related to risk of osteoporosis.  相似文献   
69.
Johanson–Blizzard syndrome is a rare autosomal recessive disorder, characterized by exocrine pancreatic deficiency and a wide range of other abnormalities. We present here an infant with failure to thrive, exocrine pancreatic deficiency, short stature and developmental delay, cutis aplasia on the scalp, aplasia of alae nasi, hypospadias, hypothyroidism, myxomatous mitral valve, and patent ductus arteriosus. Molecular studies revealed a novel homozygous nonsense mutation in exon 38 of the UBR1 gene, which confirmed the diagnosis of Johanson–Blizzard syndrome. It should be acknowledged that the combination of exocrine pancreatic insufficiency and nasal wing hypo-aplasia is pathognomonic for this syndrome. Prompt diagnosis and exact monitoring of the patients with JBS are required to avoid further complications.  相似文献   
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