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121.
122.
Most anuran larvae show large lateral oscillations at both the tip of the tail and the snout while swimming in a straight line. Although the lateral deflections at the snout have long been considered an inefficient aspect of tadpole locomotion, a recent hydrodynamic model suggests that they may in fact help generate thrust. It is not clear though exactly where this bending takes place. The vertebral column is extremely short and seemingly inflexible in anurans, and any axial flexion that might occur there is hidden within the globose body of the tadpole. Here we test the hypothesis that lateral deflections of the snout correlate with bending of the vertebral column within the torso of tadpoles. To quantify vertebral curvature, three sonomicrometry crystals were surgically implanted along the dorsal midline in locations corresponding to the anterior, middle, and posterior region of the presacral vertebral column. Swimming trials were conducted in a flume where synchronized video recordings were collected in dorsal view. Our results confirm that cyclic lateral bending occurs along the vertebral column during swimming and indicate that vertebral curvature is temporally in phase with lateral oscillation of the snout. Lateral oscillation of the snout increased significantly with increasing vertebral curvature. Similarly, tail beat amplitude also increases significantly with increasing vertebral curvature. Our results suggest that cyclic lateral flexion of the vertebral column, activated by the axial muscle within the torso of tadpoles contributes to snout oscillations and the generation of thrust during undulatory swimming in anuran larvae. 相似文献
123.
High c-myc levels are linked to poor prognosis in medulloblastoma (MB), and it was the aim of the current study to search for c-myc-dependent proteins in the MB cell line D425Med. For this purpose D425Med cells and cells with knocked-down c-myc (by siRNA) were analysed by a gel-based differential proteomics study using mass spectrometry. Heterogeneous nuclear ribonucleoproteins C1/C2, heterogeneous nuclear ribonucleoprotein A/B, stathmin, endoplasmic reticulum protein ERp29 precursor and guanidinoacetate N-methyltransferase were c-myc dependently expressed. Signalling, the protein machinery, metabolism and endoplasmic reticulum function may be affected and these results enable studying tumour tissue for these proteins as potential dignity markers or pharmacological targets. 相似文献
124.
Sheida Azizi Mohammad Ali Nematollahi Bagher Mojazi Amiri Emilio J. Vélez Esmail Lutfi Isabel Navarro Encarnación Capilla Joaquim Gutiérrez 《PloS one》2016,11(1)
Optimizing aquaculture production requires better knowledge of growth regulation and improvement in diet formulation. A great effort has been made to replace fish meal for plant protein sources in aquafeeds, making necessary the supplementation of such diets with crystalline amino acids (AA) to cover the nutritional requirements of each species. Lysine and Leucine are limiting essential AA in fish, and it has been demonstrated that supplementation with them improves growth in different species. However, the specific effects of AA deficiencies in myogenesis are completely unknown and have only been studied at the level of hepatic metabolism. It is well-known that the TOR pathway integrates the nutritional and hormonal signals to regulate protein synthesis and cell proliferation, to finally control muscle growth, a process also coordinated by the expression of myogenic regulatory factors (MRFs). This study aimed to provide new information on the impact of Lysine and Leucine deficiencies in gilthead sea bream cultured myocytes examining their development and the response of insulin-like growth factors (IGFs), MRFs, as well as key molecules involved in muscle growth regulation like TOR. Leucine deficiency did not cause significant differences in most of the molecules analyzed, whereas Lysine deficiency appeared crucial in IGFs regulation, decreasing significantly IGF-I, IGF-II and IGF-IRb mRNA levels. This treatment also down-regulated the gene expression of different MRFs, including Myf5, Myogenin and MyoD2. These changes were also corroborated by a significant decrease in proliferation and differentiation markers in the Lysine-deficient treatment. Moreover, both Lysine and Leucine limitation induced a significant down-regulation in FOXO3 gene expression, which deserves further investigation. We believe that these results will be relevant for the production of a species as appreciated for human consumption as it is gilthead sea bream and demonstrates the importance of an adequate level of Lysine in fishmeal diet formulation for optimum growth. 相似文献
125.
Golaleh Asghari Emad Yuzbashian Parvin Mirmiran Behnaz Mahmoodi Fereidoun Azizi 《PloS one》2015,10(10)
The aim of the study was to evaluate the association between fast food consumption and incidence of metabolic syndrome (MetS) and its components among children and adolescents over a 3.6 year follow-up. Dietary data of 424 healthy subjects, aged 6–18 years, was collected using a valid and reliable food frequency questionnaire. Metabolic syndrome was defined according to the Cook et al criteria. Consumption of fast foods including hamburgers, sausages, bologna (beef), and fried potatoes was calculated and further categorized to quartiles. Multiple logistic regression models were used to estimate the incidence of MetS and its components in each quartile of fast food intake. The incidence of MetS was 11.3% after a 3.6 year follow up. In the fully adjusted model, compared to the lowest quartile of fast food intake, individuals in the highest had odds ratios of 2.96 (95% CI: 1.02–8.63; P for trend<0.001), 2.82 (95% CI: 1.01–7.87; P for trend = 0.037), and 2.58 (95% CI: 1.01–6.61; P for trend = 0.009) for incidence of MetS, hypertriglyceridemia, and abdominal obesity, respectively. No significant association was found between fast food intakes and other components of MetS. Fast food consumption is associated with the incidence of MetS, abdominal obesity, and hypertriglyceridemia in Tehranian children and adolescents. 相似文献
126.
Introduction
Different variants of haplotype frequencies may lead to various frequencies of the same variants in individuals with drug resistance and disease susceptibility at the population level.Materials and methods
In this study, the haplotype frequencies of 4 STR loci including the D8S1132, D8S1779, D8S514 and D8S1743, and 3 STR loci including D11S1304, D11S1998 and D11S934 were investigated in 563 individuals of four Iranian ethnic groups in the capital city of Iran, Tehran. One hundred thirty subjects had the metabolic syndrome. Haplotype frequencies of all markers were calculated.Results
There were significant differences in the haplotype frequencies in short and long alleles between the metabolic affected subjects and controls. In addition, haplotype frequencies were significant in the four ethnic groups in both chromosomes 8 and 11.Conclusion
Our findings show a relation between the short allele of D8S1743 in all related haplotype frequencies of subjects with metabolic syndrome. These findings may require more studies of some candidate genes, including the lipoprotein lipase gene, in this chromosomal region. 相似文献127.
Maryam Tohidi Mitra Hasheminia Reza Mohebi Davood Khalili Farhad Hosseinpanah Babak Yazdani Amir Ahmad Nasiri Fereidoun Azizi Farzad Hadaegh 《PloS one》2012,7(9)
To examine, the predictors of incident chronic kidney disease (CKD) in a community-based cohort of Middle East population, during a mean follow-up of 9.9 years. In a sample of 3313 non-CKD Iranian adults ≥20 years the estimated glomerular filtration rate (eGFR) was calculated at baseline and at three year intervals during three consecutive phases. The eGFR <60 mL/min/1.73 m2 was defined as CKD. Multivariate Logistic regression analysis was used to determine the independent variables associated with incident CKD. The incidence density rates of CKD were 285.3 and 132.6 per 10,000 person-year, among women and men, respectively. Female gender per se was associated with higher risk of CKD, compared with males. Among women, age, eGFR, known diabetes, being single or divorced/widowed, hypertension (marginally significant) and current smoking were independent risk factors for CKD; however the intermediate degree of education and family history of diabetes decreased the risk by 40% (P<0.05). Among male subjects, independent predictors of developing CKD included aging and hypertension (with significantly higher risk than in women, P for interaction<0.05), eGFR, new diagnosed diabetes, high normal blood pressure; abdominal obesity decreased the risk of CKD about 30% which was marginally significant. In the Iranian population,>2% of individuals develops CKD each year. Our findings confirmed that sex- specific risk predictors should be considered in primary prevention for incident CKD. 相似文献
128.
Khalili D Mosavi-Jarrahi A Eskandari F Mousavi-Jarrahi Y Hadaegh F Mohagheghi M Azizi F 《PloS one》2012,7(2):e31427
Objective
The aim of this study was to evaluate the validity of cause of death stated in death certificates in Tehran using outcome measures of the Tehran Lipid and Glucose Study (TLGS), an ongoing prospective cohort study.Methods
The cohort was established in 1999 in a population of 15005 people, 3 years old and over, living in Tehran; 3551 individuals were added to this population three years later. As part of cohort''s outcome measures, deaths occurring in the cohort are investigated by a panel of medical specialists (Cohort Outcome Panel-COP) and underlying cause of death is determined for each death. The cause of death assigned in a deceased''s original death certificate was evaluated against the cause of death determined by COP and sensitivity and positive predictive values (PPV) were determined. In addition, determinants of assigning accurate underlying cause of death were determined using logistic regression model.Result
A total of 231 death certificates were evaluated. The original death certificates over reported deaths due to neoplasms and underreported death due to circulatory system and transport accidents. Neoplasms with sensitivity of 0.91 and PPV of 0.71 were the most valid category. The disease of circulatory system showed moderate degree of validity with sensitivity of 0.67 and PPV of 0.78. The result of logistic regression indicated if the death certificate is issued by a general practitioner, there is 2.3 (95% CI 1.1, 5.1) times chance of being misclassified compared with when it is issued by a specialist. If the deceased is more than 60 years, the chance of misclassification would be 2.5 times (95% CI of 1.1, 5.9) compared with when the deceased is less than 60 years. 相似文献129.
SS Eghbali R Amirinejad N Obeidi S Mosadeghzadeh K Vahdat F Azizi R Pazoki Z Sanjdideh Z Amiri I Nabipour K Zandi 《Virology journal》2012,9(1):194
ABSTRACT: BACKGROUND: Epidemiological studies on genital human papilloma viruses infection (HPVs) in general population are crucial for the implementation of health policy guidelines for developing the strategies to prevent the primary and secondary cervical cancer. In different parts of Iran, there is a lack of population-based studies to determine the prevalence of HPV in the general population. The aim of this population-based study is to compare the prevalence rate of genital HPV infection among reproductive women with our previous clinic-based data, which showed a prevalence rate of 5% in women in southern Iran. RESULTS: Using general primers for all genotypes of HPV, of 799 randomly selected women, five (0.63%, 95% CI 0.23-1.55%) tested positive for HPV DNA. Overall, seven different HPV genotypes were detected: six types (16, 18, 31, 33, 51 and 56) were carcinogenic, or "high risk genotypes" and one genotype (HPV-66) was "probably carcinogenic." CONCLUSIONS: In a population-based study, the prevalence of HPV infection among southern Iranian women was lower than that observed worldwide. However, our gynaecological clinic-based study on the prevalence of HPV infection showed results comparable with other studies in the Middle East and Persian Gulf countries. Since gynaecological clinic-based data may generally overestimate HPV prevalence, estimates of prevalence according to clinic-based data should be adjusted downward by the population-based survey estimates. 相似文献
130.
Deregulation of microRNAs by HIV-1 Vpr protein leads to the development of neurocognitive disorders.