Lifespan Trajectories of White Matter Changes in Rhesus Monkeys.

Progress in neurodevelopmental brain research has been achieved through the use of animal models. Such models not only help understanding biological changes that govern brain development, maturation and aging, but are also essential for identifying possible mechanisms of neurodevelopmental and age-related chronic disorders, and to evaluate possible interventions with potential relevance to human disease. Genetic relationship of rhesus monkeys to humans makes those animals a great candidate for such models. With the typical lifespan of 25 years, they undergo cognitive maturation and aging that is similar to this observed in humans. Quantitative structural neuroimaging has been proposed as one of the candidate in vivo biomarkers for tracking white matter brain maturation and aging. While lifespan trajectories of white matter changes have been mapped in humans, such knowledge is not available for nonhuman primates. Here, we analyze and model lifespan trajectories of white matter microstructure using in vivo diffusion imaging in a sample of 44 rhesus monkeys. We report quantitative parameters (including slopes and peaks) of lifespan trajectories for 8 individual white matter tracts. We show different trajectories for cellular and extracellular microstructural imaging components that are associated with white matter maturation and aging, and discuss similarities and differences between those in humans and rhesus monkeys, the importance of our findings, and future directions for the field. Significance Statement: Quantitative structural neuroimaging has been proposed as one of the candidate in vivo biomarkers for tracking brain maturation and aging. While lifespan trajectories of structural white matter changes have been mapped in humans, such knowledge is not available for rhesus monkeys. We present here results of the analysis and modeling of the lifespan trajectories of white matter microstructure using in vivo diffusion imaging in a sample of 44 rhesus monkeys (age 4-27). We report and anatomically map lifespan changes related to cellular and extracellular microstructural components that are associated with white matter maturation and aging.

Estimation of birth weight by measurement of fundal height and abdominal girth in parturients at term.

in a prospective descriptive study, the usefulness of symphysis-fundal height and the product of abdominal girth and fundal height in predicting birth weight < 2500 g and > 4000 g were examined. Fundal height and abdominal girth were measured at the time of admission on a sample of 795 parturient women at ateaching hospital in the Islamic Republic of Iran. Receiver operating characteristics curve analysis was used to select the best cut-off points. The product of abdominal girth x fundal height with the cut-off at 3900 g performed better for predicting birth weight > 4000 g, but for low birth weight, the regression model of fundal height with cut-off at 3000 g was a better predictor.

Marginal adaptation of composite restorations versus hybrid ionomer/composite sandwich restorations.

The aim of this in vitro study was to compare the approximal marginal quality of composite fillings using a dentin bonding system to the marginal quality of hybrid ionomer/composite sandwich restorations. Forty-eight standardized class 2 cavity preparations were prepared in caries-free, human third molars. Twelve preparations at a time were filled either with a composite using the matching dentin bonding system, SZ (Scotchbond MP/Z100) or PP (PROBOND/Prisma TPH) or with hybrid ionomer/composite sandwich fillings VZ (Vitremer/Z100) or DP (Dyract/Prisma TPH). Margins were evaluated before and after thermomechanical loading (TCML) (5000 cycles [+5 degrees C/+55 degrees C], 72.5 N [1,7 Hz]) by quantitative scanning electron microscope analysis using an image analyzing system. Furthermore, microleakage was assessed by dye penetration before and after TCML. Statistical analysis was performed using the Mann-Whitney test at the 0.05 level of significance. SEM analysis after TCML showed significantly fewer marginal gaps at the material/dentin interface with VZ (2.2%), DP (7.3%), and PP (6.0%) compared to SZ (29.6%). After TCML, SZ showed significantly more marginal gaps at the material/dentin interface, whereas VZ, DP, and PP were not susceptible to TCML. PP showed the highest percentage in marginal swelling before (18.2%) and after TCML (15.9%), while VZ showed no marginal swelling at all. VZ showed significantly fewer marginal gaps at the composite/hybrid ionomer interface than DP. After TCML there was no significant difference in marginal gaps between the hybrid ionomer/enamel and the hybrid ionomer/dentin interface for both Vitremer and Dyract. Using the sandwich technique the Z100/enamel interface had significantly more marginal gaps than all other composite/enamel interfaces after TCML. There was no significant difference in microleakage between the test groups at the material/dentin interface. SEM analysis and dye penetration showed that hybrid ionomer/composite sandwich restorations have good marginal qualities and may be an alternative to composite restorations using a dentin bonding system.

NPHS1 gene mutations in children with Nephrotic Syndrome in northwest Iran.

Idiopathic Nephrotic Syndrome (NS) is the prevalent glomerular disease in childhood. It is treated with steroid and according to its response is defined as steroid sensitive NS (SSNS) and steroid resistance NS (SRNS). Mutation in NPHS 1 gene is reported in children with SRNS and few cases of SSNS. The aim of current study is to evaluate NPHS1 gene mutations in idiopathic NS (SSNS and SSRS) in Northwest Iran. In this cross-sectional analytic study 20 children from Azeri population in Iran with idiopathic NS including 10 cases with SRNS (5 male and 5 female) and 10 cases with SSNS (7 male and 3 female) were evaluated for NPHS1 gene mutations. DNA was extracted from peripheral blood and NPHSI gene analysis was performed by PCR and direct sequencing method with the use of standard primers. Mutations in NPHS1 gene occurred in 6 cases of SSNS including 3 heterozygous and 3 homozygous mutations and in 8 cases of SRNS including 5 homozygous, one compound heterozygous and 2 heterozygous mutations. Overall 6 different mutations were detected in NPHS1 gene: one deletion, one insertion, 3 missense and one nonsense mutations. Mutations in exon 4 and 27 were only seen in SRNS patients. Mutations in NPHS1 gene could occur in both SRNS and SSNS patients; however, considering higher incidence of heterozygous mutations in SSNS, the existence of milder phenotype in these cases would be the reason for steroid response.

Management and outcome of children with end-stage renal disease in northwest Iran.

Outcome of end-stage renal disease (ESRD) in children has considerably improved since the development of dialysis and kidney transplantation. This study was conducted to evaluate the management and outcome of ESRD children in a referral pediatric center in northwest Iran. A cross-sectional study of medical records of ESRD children (glomerular filtration rate less than 15 ml/min/1.73 m(2)) younger than 16 years who were admitted in Children's Hospital of Tabriz between October 1999 and October 2009 was performed. Ninety-four children with ESRD including 51 boys (54.3%) and 43 girls (45.7%) with a mean age of 7.9 ± 3.49 years were studied. Parents of nine patients (7.8%) refused treatment. Eighty patients underwent renal replacement therapy (RRT) and were followed for a mean period of 4.86 ± 2.77 years. Initial modality of RRT was hemodialysis in 81.25%, continuous ambulatory peritoneal dialysis in 16.25%, and preemptive kidney transplantation in 2.5%. Thirty-two patients (34%) underwent renal transplantation. The mean duration of staying on dialysis before transplantation was 12.4 ± 11 months. Twenty-nine of kidney donors (90.6%) were living unrelated donors. The 1-and 3-year graft survival rates were 81.2% and 68.8% and the 1- and 3-year patient survival rates were 96.9% and 93.8%, respectively. Thirty-one patients died (33%). The mortality of girls was significantly higher than boys (P=0.04). There was a significant negative correlation between age and mortality (P=0.01). Heart failure and infections were the most common cause of death. This study showed that ESRD children in our area have a poor outcome in comparison with developed countries.

Etiology of pediatric chronic kidney diseases in north-west of Iran.

The aim of this study was to evaluate the etiology of pediatric Chronic Kidney Disease (CKD) in a tertiary care hospital in north-west of Iran. Medical records of admitted children with CKD in Children's Hospital of Tabriz from 1999 to 2009 were studied retrospectively. CKD was defined as GFR less than 60 mL min(-1) 1.73 m2 for more than 3 month. The etiology of CKD was determined by clinical, biological, radiological and histopathological examination. During 10 years 115 children including 61 boys (53%) and 54 girls (47%) were studied. The mean age of patients was 8.1 +/- 3.53 years (range: 4 months to 14 years). Urological abnormalities were the most common cause of CKD (36.5%) followed by acquired glomerular diseases (23.5%), hereditary nephropathies (21.7%), unknown etiology (9.5%) and systemic diseases (6%). The most common urologic anomaly was vesicoureteral reflux (VUR) that accounted for 24.3% of total etiologies followed by obstructive uropathies. Focal segmental glomerulosclerosis was the most frequent glomerular disease and was responsible for 13.9% of patients. Nephronophtisis, cystinosis, infantile polycystic disease and congenital nephrotic syndrome were the most frequent hereditary nephropathies in a descending order. Frequency of parental consanguinity in patients with hereditary nephropathy was significantly higher than other patients (p = 0.001). High frequency of VUR in present study compared with developed countries necessitates more efforts for improving the management and follow up of urinary tract infections.

Underlying etiologies of prolonged icterus in neonates.

The purpose of this study was to determine underlying causes of prolonged neonatal icterus. Icterus or jaundice is an important common problem in neonatology. When this condition persists beyond 14 days, it is called prolonged or protracted neonatal icterus. Determining underlying causes of this problem is a pivotal step for management, because a delay in treatment may lead to serious complications or even death. In a prospective study, newborns with diagnosis of prolonged icterus were evaluated during a six-month period in Tabriz Children Teaching Hospital. Data regarding the past medical history, physical examination and appropriate laboratory and paraclinical investigations were gathered and accordingly, the underlying cause of jaundice was documented. One hundred newborns, 67 males and 33 females with a mean age of 21.5 +/- 4.5 days were enrolled. Breastfeeding, urinary tract infection, glucose 6-phosphate dehydrogenase deficiency and hypothyroidism were found as the main underlying causes in 75, 7, 7 and 4% of the cases. The exact etiology was unknown in 4% of newborns. ABO incompatibility, sepsis and Down syndrome were underlying etiologies in remaining three patients. Present study showed that the underlying causes of prolonged neonatal jaundice could be determined in majority of cases and breastfeeding is the most common one in this regard.

Estimation of birth weight by measurement of fundal height and abdominal girth in parturients at term

In a prospective descriptive study, the usefulness of symphysis-fundal height and the product of abdominal girth and fundal height in predicting birth weight < 2500 g and > 4000 g were examined. Fundal height and abdominal girth were measured at the time of admission on a sample of 795 parturient women at a teaching hospital in the Islamic Republic of Iran. Receiver operating characteristics curve analysis was used to select the best cut-off points. The product of abdominal girth _ fundal height with the cut-off at 3900 g performed better for predicting birth weight > 4000 g, but for low birth weight, the regression model of fundal height with cut-off at 3000 g was a better predictor