MicroRNAs and lung development

MicroRNAs (miRNAs) constitute a large group of small (～22 nucleotides), non‐coding RNA sequences that are highly conserved among animals, plants and microorganisms, suggesting that microRNAs represent a highly conserved and important regulatory mechanism. They have been demonstrated to play an important role in gene regulation. Recently, miRNAs have become a major focus of interest for research in organ development. Research focusing on the potential role of microRNAs during lung development is slowly starting to emerge. A number of miRNAs have been demonstrated to play important roles during early and late lung development. Several studies have begun to profile miRNA expression at various stages of lung development and this article provides an overview of the various miRNAs that have been implicated in lung organogenesis. Pediatr Pulmonol. 2013; 48:317–323. © 2012 Wiley Periodicals, Inc.     

Rectal bleeding secondary to fecal disimpaction: angiographic diagnosis and treatment.

Two cases of bleeding caused by manual disimpaction of fecal material are presented. Angiography played a critical role in the diagnosis and treatment. One case was managed with balloon tamponade, and the other was successfully treated by selective intra-arterial vasopressin infusion, after prior intravenous infusion had been ineffective. A history of fecal disimpaction should suggest the possibility of low rectal bleeding which can be diagnosed and treated angiographically.     

Degradation of cyclin D3 independent of Thr-283 phosphorylation

Cyclin D3 has been shown to play a major role in the regulation of cell cycle progression in lymphocytes. It is therefore important to understand the mechanisms involved in the regulation of this protein. We have previously shown that both basal and cAMP-induced degradation of cyclin D3 in Reh cells is dependent on Thr-283 phosphorylation by glycogen synthase kinase-3beta (GSK-3beta). We now provide evidence of an alternative mechanism being involved in the regulation of cyclin D3 degradation. Treatment of lymphoid cells with okadaic acid (OA), an inhibitor of protein phosphatases 1 and 2A (PP1 and PP2A), induces rapid phosphorylation and proteasomal degradation of cyclin D3. This degradation is not inhibited by the GSK-3beta inhibitors lithium or Kenpaullone, or by substitution of Thr-283 with Ala on cyclin D3, indicating that cyclin D3 can be degraded independently of Thr-283 phosphorylation and GSK-3beta activity. Interestingly, in vitro experiments revealed that PP1, but not PP2A, was able to dephosphorylate cyclin D3 efficiently, and PP1 was found to associate with His-tagged cyclin D3. These results support the hypothesis that PP1 constitutively keeps cyclin D3 in a stable, dephosphorylated state, and that treatment of cells with OA leads to phosphorylation and degradation of cyclin D3 through inhibition of PP1.     

Body Fat Distribution and Its Association with Cardiovascular Risk Factors in Adolescent Iranian Girls

Objective

The relationships between body fat distribution, lipid profile and blood pressure, have not been studied extensively in young population. This study was designed to evaluate the association between measures of adiposity and established cardiovascular risk factors in adolescent girls.

Methods

A total of 477 adolescent girls aged 15 to 18 years were recruited from Mashhad high schools. Socio-demographic characteristics were assessed using a self-administered questionnaire. Anthropometric assessments, blood pressure measurement and biochemical assessment were performed. Total and regional fat mass were determined by bio-impedance analysis. Cardiovascular disease risk factors were assessed in relation to body fat measures with adjustment for confounder factors including age and family socioeconomic status.

Findings

The prevalence of overweight and obesity was 14.6% and 3.4% respectively; 16% of study population had greater fat mass compared to its ideal distribution. The majority of cardiovascular risk factors, especially systolic and diastolic blood pressure, triglyceride concentration, CRP and fasting blood sugar were significantly higher in group with a high body fat when compared to those with normal and low values. All anthropometric indices showed significant correlation with fat mass, fat free mass, total and regional body fat percent (P<0.001). After adjustment for age and family socioeconomic status, a high fat mass especially, truncal fat, was positively associated with triglyceride and blood pressure.

Conclusion

Adiposity, especially truncal adiposity, which can be assessed by simple measures such as Body Mass Index (BMI) and Waist Circumference (WC) may predispose adolescent girls for demonstration of metabolic abnormalities and consequently cardiovascular diseases.     

Genetic Characterization of a Vancomycin-Resistant Staphylococcus aureus Isolate from the Respiratory Tract of a Patient in a University Hospital in Northeastern Iran

Emergence of vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains has led to global concerns about treatments for staphylococcal infections. These strains are currently rare even though there is an upward trend in their reported incidence. Therefore, appropriate screening and epidemiological evaluation of VRSA strains can affect future global health care policies. Isolates of Staphylococcus aureus were obtained from various clinical samples and were then evaluated with agar screening, disk diffusion, and MIC methods to determine resistance to vancomycin and methicillin. After confirmation of the isolated VRSA strain, genetic analysis was performed by evaluating mecA and vanA gene presence, SCCmec, agr, and spa types, and toxin profiles. Multilocus sequence typing (MLST) and plasmid analysis were also performed. The VRSA strain was resistant to oxacillin (MIC of 128 μg/ml) and vancomycin (MIC of 512 μg/ml). Disk diffusion antimicrobial susceptibility tests showed resistance to oxacillin, vancomycin, levofloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, clindamycin, rifampin, and tetracycline. The isolate was susceptible to minocycline and gentamicin. PCRs were positive for the mecA and vanA genes. Other genetic characteristics include SCCmec type III, agr I, spa type t037, and sequence type (ST) 1283. The plasmid profile shows five plasmids with a size of ∼1.7 kb to >10 kb. The isolated VRSA strain was obtained from a critically ill hospitalized patient. Genetic analysis of this strain suggested that the strain was a methicillin-resistant S. aureus (MRSA) clone endemic in Asia that underwent some genetic changes, such as mutation in the gmk gene and acquisition of the vanA gene.     

Kidney function tests in children with beta-thalassemia minor in Zahedan, southeast of Iran

There is little information regarding kidney function in patients with beta-thalassemia minor. In this study we investigated kidney function tests in 50 children with beta-thalassemia minor (22 boys and 28 girls). Twenty-four-hour urine samples were collected and analyzed for sodium, potassium, calcium, magnesium, creatinine, phosphate, uric acid, protein, and beta2-microglobulin. Blood samples were obtained for hematologic and biochemical analyses including complete blood count, serum ferritin, sodium, potassium, calcium, phosphate, magnesium, creatinine, and uric acid. This group of children with beta-thalassemia showed some evidence of tubulopathy such as proteinuria (32%), beta2-microglobulin excretion (36%), calciuria (4%), phosphaturia (4%), and uricosuria (20%). Our findings support the existence of renal tubular dysfunction in beta-thalassemia minor. However, further studies in large series are needed to shed light on the possible relation of these two distinct diseases.     

Response to a letter to the editor by Mohammad Rasoul Ghadami et al.: “Obstructive sleep apnea in veterans with post-traumatic stress disorder: looking beyond their complaint”

Sleep and Breathing -     

Nailfold capillaroscopy in Beh?et’s disease,analysis of 128 patients

The aims of this study were to find the characteristics and prevalence of nailfold capillary changes in a large series of patients with Behçet’s disease (BD) and to analyze their possible relation to other clinical characteristics of the disease. We performed nailfold capillaroscopy in 128 randomly selected patients fulfilling the international classification criteria for BD. Capillaroscopy was done in eight fingers with a ×3.2 microscopy. All patients were questioned for history of Raynaud's phenomenon, ischemic ulcers, smoking, and hypertension. A computerized form including demographic, clinical, and para-clinical features was used to collect data. Univariate and multivariate logistic regressions were used to analyze the relation between capillaroscopic findings and disease characteristics. Odds ratio and a confidence interval at 95% (CI) were calculated for each item. The mean age of the patients was 37?±?10 years, and the male to female ratio was 1.56:1. Capillaroscopy was abnormal in 51 patients (40%, CI 8.5). Enlarged capillaries were seen in 33 patients (26%, CI 7.6), hemorrhages in 21 (16%, CI 6.4), and capillary loss only in one patient. In univariate logistic regression analysis, the presence of enlarged capillaries was associated with lower age at disease onset (OR?=?0.9, CI 0.9–1; p?=?0.04), hypertension (OR?=?4.2, CI 1.5–11.4; p?=?0.006), superficial phlebitis (OR?=?5.5, CI 1.2–24.4; p?=?0.03), and negative pathergy test (OR?=?0.4, CI 0.2–0.9; p?=?0.04). The presence of hemorrhages tended to be associated with articular symptoms (p?=?0.05). Multivariate analysis also confirmed the association of enlarged capillaries with lower age at disease onset (p?=?0.01), hypertension (p?=?0.001), and superficial phlebitis (p?=?0.03). Nailfold abnormalities, mainly enlarged capillaries, are frequent in patients with BD. Our results suggest that these abnormalities may be related to other vascular features of the disease such as superficial phlebitis, but it does not seem to confer special risk for any other specific clinical symptom of the disease.