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61.

Objective

To assess the national inequality of school readiness and autism among 6-year-old Iranian children before school entry using a national health assessment survey.

Methods

In a cross-sectional nationwide survey, all Iranian children entering public and private elementary schools were asked to participate in a mandatory national screening program in Iran in 2009 in two levels of screening and diagnostic levels.

Findings

The study population consisted of 955388 children (48.5% girls and 76.1% urban residents). Of the whole children, 3.1% of the 6-year-old children had impaired vision. In addition, 1.2, 1.8, 1.4, 7.6, 0.08, 10, 10.9, 56.7, 0.7, 0.8 and 0.6 percent had color blindness, hearing impaired, speech disorder, school readiness, autism, height to age retardation, body mass index extremes, decayed teeth, disease with special needs, spinal disorders, and hypertension, respectively. The distribution of these disorders was unequally distributed across provinces.

Conclusion

Our results confirmed that there is an inequality in distribution of school readiness and autism in 6-year-old children across Iranian provinces. The observed burden of these distributions among young children needs a comprehensive national policy with evidence-based province programs to identify the reason for different inequality among provinces.  相似文献   
62.
Background: Mammographic density determined according paranchymal patterns is a risk factor for breast cancer and its relationships with body and other breast characteristics of women is important. The purpose of the present study was to correlate breast parenchymal patterns and mammography abnormality findings with women's BMI, compressed breast thickness (CBT) and age in Tabriz city, Iran. Materials and Methods: From 1,100 mammograms interpreted by radiologists, breast parenchymal was classified into four categories from Types 1 (mostly fatty) through 4 (mostly fibroglandular tissue). Age, BMI, and CBT were recorded and their relation with risk for the development of breast abnormalities in mammograms was analyzed. Results: In women with a mean age of 45.88.63 years 17.7% were in the high density group (Type 3 and 4). A comparison of four types of breast paranchymal with BMI, CBT and age showed inverse relations to breast density. Abnormal mammographic findings were 25.8% of all reported mammograms with a circular mass (12.7%) as the most common abnormality. About 21% abnormal cases were in less than 40 years. Increasing of BMI had significant relation with breast abnormality but in CBT was not observed. Conclusions: Measurement of women's body characteristics is useful for assistance in mammography diagnosis as well as selection of imaging instrument by high sensitivity for following patient in future. The effects of age, CBT and BMI groups on the breast paranchymal were significant.  相似文献   
63.

Background

Proper patterning of dendritic and axonal arbors is a critical step in the formation of functional neuronal circuits. Developing circuits rely on an array of molecular cues to shape arbor morphology, but the underlying mechanisms guiding the structural formation and interconnectivity of pre- and postsynaptic arbors in real time remain unclear. Here we explore how Down syndrome cell adhesion molecule (DSCAM) differentially shapes the dendritic morphology of central neurons and their presynaptic retinal ganglion cell (RGC) axons in the developing vertebrate visual system.

Methods

The cell-autonomous role of DSCAM, in tectal neurons and in RGCs, was examined using targeted single-cell knockdown and overexpression approaches in developing Xenopus laevis tadpoles. Axonal arbors of RGCs and dendritic arbors of tectal neurons were visualized using real-time in vivo confocal microscopy imaging over the course of 3 days.

Results

In the Xenopus visual system, DSCAM immunoreactivity is present in RGCs, cells in the optic tectum and the tectal neuropil at the time retinotectal synaptic connections are made. Downregulating DSCAM in tectal neurons significantly increased dendritic growth and branching rates while inducing dendrites to take on tortuous paths. Overexpression of DSCAM, in contrast, reduced dendritic branching and growth rate. Functional deficits mediated by tectal DSCAM knockdown were examined using visually guided behavioral assays in swimming tadpoles, revealing irregular behavioral responses to visual stimulus. Functional deficits in visual behavior also corresponded with changes in VGLUT/VGAT expression, markers of excitatory and inhibitory transmission, in the tectum. Conversely, single-cell DSCAM knockdown in the retina revealed that RGC axon arborization at the target is influenced by DSCAM, where axons grew at a slower rate and remained relatively simple. In the retina, dendritic arbors of RGCs were not affected by the reduction of DSCAM expression.

Conclusions

Together, our observations implicate DSCAM in the control of both pre- and postsynaptic structural and functional connectivity in the developing retinotectal circuit, where it primarily acts as a neuronal brake to limit and guide postsynaptic dendrite growth of tectal neurons while it also facilitates arborization of presynaptic RGC axons cell autonomously.
  相似文献   
64.
Pharmaceutical Research - Sterile filtration can be a particular challenge when processing very large glycoconjugate vaccines. The objective of this study was to examine the sterile filtration...  相似文献   
65.

Introduction

This study aims to investigate the relationship of water hardness and its calcium and magnesium content with endothelial function in a population-based sample of healthy children and adolescents.

Material and methods

This case-control study was conducted in 2012 among 90 individuals living in two areas with moderate and high water hardness in Isfahan County, Iran. The flow-mediated dilatation (FMD) of the brachial artery and the serum levels of soluble adhesion molecules (sICAM-1, sVCAM-1) were measured as surrogate markers of endothelial function, and high-sensitivity C-reactive protein (hs-CRP), as a marker of inflammation.

Results

Data of 89 participants (51% boys, mean age 14.75 (2.9) years) were complete. Those participants living in the area with high water hardness had higher FMD, hs-CRP, and soluble adhesion molecules (sICAM-1, sVCAM-1) than their counterparts living in the area with moderate water hardness. Multiple linear regression analysis showed that after adjustment for confounding factors of age, gender, body mass index, healthy eating index and physical activity level, total water hardness, as well as water content of calcium and magnesium, had a significant positive relationship with FMD. The corresponding associations were inverse and significant with soluble adhesion molecules (p < 0.05).

Conclusions

This study, which to the best of our knowledge is the first of its kind in the pediatric age group, suggests that water hardness, as well as its calcium and magnesium content, may have a protective role against early stages of atherosclerosis in children and adolescents.  相似文献   
66.
ObjectiveThis nationwide study was conducted to determine the association of anthropometric measures with cardiovascular risk factors and metabolic syndrome (MetS) in Iranian normal-weight children and adolescents.MethodsWe analyzed the data of 3,565 children and adolescents (50.3% boys), aged 10-18 years, with a normal BMI (5th-84th percentile) obtained from the third survey of ‘Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease’ (CASPIAN III) study. The diagnostic criteria for MetS were defined by the International Diabetes Federation consensus.ResultsThe prevalence of MetS for 10- to 13.9-year-old boys, 14- to 18-year-old boys, 10- to 13.9-year-old girls, and 14- to 18-year-old girls were 1.4, 2.8, 2.3, and 3.3%, respectively. After adjustment for age and sex, each unit increase in BMI (within normal range) and waist circumference increased the odds of MetS from 6 to 72% and from 1 to 20%, respectively. The dominant pattern of dyslipidemia among the participants was high triglycerides and low high-density lipoprotein cholesterol.ConclusionThis study complements recent research about the high frequency of metabolic risk factors among normal-weight individuals in the pediatric age group.Key Words: Anthropometric, Cardiovascular, Metabolic syndrome, Children, Adolescents  相似文献   
67.
Objectivethis study aimed to evaluate the association of breakfast intake with cardiometabolic risk factors in a nationally-representative sample of Iranian pediatrics.Methodsthe study participants considered of 5,625 school students aged 10-18 years, studied in the third survey of the national school-based surveillance system (CASPIAN-III). They were classified into three groups based on the number of days they ate breakfast: “regular breakfast eater” (6-7days/week), “often breakfast eater” (3-5days/week), and “seldom breakfast eater” (0-2 days/week). Metabolic syndrome (MetS) was defined based on the Adult Treatment Panel III (ATP III) criteria modified for the pediatric age group. Moreover, high total cholesterol, high low-density lipoprotein cholesterol (LDL-C) and generalized obesity were included as other cardiometabolic risk factors. Multiple logistic regression analyses were used to evaluate the association between the breakfast intake category and cardiometabolic risk factors.Resultsthe number of subjects classified as “regular”, “often” and “seldom” breakfast eaters were 2,653(47.3%), 1,327(23.7%) and 1,624(29.0%), respectively. The average of triglycerides (TG), LDL-C, systolic blood pressure (SBP) and body mass index (BMI) were higher in the “seldom breakfast eater” group (P for trend<0.001), whereas the mean of high-density lipoprotein cholesterol (HDL-C) was lower in this group than their other counterparts. Seldom breakfast eaters had an increased risk of obesity, elevated TG and LDL-C, as well as low HDL-C compared to “regular breakfast eaters”. The risk of MetS was significantly increased in subjects who seldom ate breakfast (OR 1.96, 95% CI 1.18-3.27).Conclusionsskipping breakfast is associated with increased risk of MetS and other cardiometabooic factors in children and adolescents. Promoting the benefit of eating breakfast could be a simple and important implication to prevent these risk factors.  相似文献   
68.
69.
Introduction: The use of occipital nerve stimulators for the treatment of migraines has recently been suggested. However, there have been reports of complications, including lead migration causing local muscle stimulation and spasm with local burning sensation and loss of successful neuromodulation. Case: We report a case of a patient who had successful permanent implantation and then presented with suspicion of lead migration. Upon examination of the lead at time of repositioning it was found that the insulation had eroded and the conducting wires exposed at the anchor site. Discussion: Disruption of occipital nerve stimulator lead insulation may mimic lead migration with failure of neuromodulation, spasm, and local burning sensations. Prior to reimplanting, a lead should be thoroughly inspected to ensure there is no mechanical failure. Anchoring should be performed with gentle direct suturing or the use of a protective anchoring device.  相似文献   
70.
Natural polymer-derived materials have attracted increasing interest in the biomedical field. Polysaccharides have obvious advantages over other polymers employed for biomedical applications due to their exceptional biocompatibility and biodegradability. None of the spherical embolic agents used clinically is biodegradable. In the current study, microspheres prepared from chitosan and carboxymethyl cellulose (CMC) were investigated as a biodegradable embolic agent for arterial embolization applications. Aside from the enzymatic degradability of chitosan units, the cross-linking bonds in the matrix, Schiff bases, are susceptible to hydrolytic cleavage in aqueous conditions, which would overcome the possible shortage of enzymes inside the arteries. The size distribution, morphology, water retention capacity and degradability of the microspheres were found to be affected by the modification degree of CMC. An anticancer drug, doxorubicin, was successfully incorporated into these microspheres for local release and thus for killing cancerous cells. These microspheres demonstrated controllable degradation time, variable swelling and tunable drug release profiles. Co-culture with human umbilical vein endothelial cells revealed non-cytotoxic nature of these microspheres compared to monolayer control (P > 0.95). In addition, a preliminary study on the in vivo degradation of the microspheres (100–300 μm) was performed in a rabbit renal embolization model, which demonstrated that the microspheres were compatible with microcatheters for delivery, capable of occluding the arteries, and biodegradable inside arteries. These microspheres with biodegradability would be promising for embolization therapies.  相似文献   
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