Ataxia telangictasia mutated (ATM) is involved in DNA repair pathway and cell-cycle checkpoints. ATM alterations were found in medulloblastomas, gliomas, but not in astrocytoma. The polymorphism D1853N was reported in healthy individuals and medulloblastomas. We could observe this polymorphism, heterozygously, in a proband affected with astrocytoma and traced it through her pedigree. We propose the three-hit hypothesis as a triangle initiators includes D1853N as a first predisposing hit, IVS 38- 63T --> A as a second hit deriving from the first somatic evolution before differentiation and IVS 38- 30 A --> G as a third hit through the development of an astrocytoma. In addition, the D1853N polymorphism was occurred in different allele from IVS 38- 63T --> A and IVS 38- 30 A --> G.

One of the most complex and important features of both the nervous and immune systems is their data storage and retrieval capability. Both systems encounter a common and complex challenge on how to overcome the cumbersome task of data management. Because each neuron makes many synapses with other neurons, they are capable of receiving data from thousands of synaptic connections. The immune system B and T cells have to deal with a similar level of complexity because of their unlimited task of recognizing foreign antigens. As for the complexity of memory storage, it has been proposed that both systems may share a common set of molecular mechanisms. Here, we review the molecular bases of memory storage in neurons and immune cells based on recent studies and findings. The expression of certain molecules and mechanisms shared between the two systems, including cytokine networks, and cell surface receptors, are reviewed. Intracellular signaling similarities and certain mechanisms such as diversity, memory storage, and their related molecular properties are briefly discussed. Moreover, two similar genetic mechanisms used by both systems is discussed, putting forward the idea that DNA recombination may be an underlying mechanism involved in CNS memory storage.

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Background: Respiratory system is an important section in development of maxillofacial components and many studies indicated its effect on normal growth of the jaws. The aim of this study is to evaluate upper airway in different skeletal classifications of jaws in lateral cephalogram and its relation to age and gender. Materials and Methods: Study samples were 105 digital cephalometric radiographies, 72 females and 33 males. Lateral cephalograms were hand traced and based on Stainer analysis, there were 30 samples in Class I, 30 samples in Class II and 45 samples in Class III subgroup. Vertical linear measurements, horizontal linear measurements, and angular measurement, proportions and space measurements of the airway in the Cephalograms were analyzed by AutoCAD software. Results: Data were analyzed using SPSS software version 20. Two horizontal linear measurement (the hypo pharyngeal airway depth, the nasopharyngeal airway depth) and one space measurement (soft palate space) were significantly different in skeletal classes. Vertical and horizontal linear measurements in the 3 groups were increased significantly in men rather than women. The developmental age of groups showed some significant differences. Conclusion: Upper airway dimension is different in different skeletal classes, developmental ages, and gender.

The long interspersed elements-1 (LINE1 or L1 retrotransposon) constitute 17% of the human genome and retain mobility properties within the genome. At present, 80-100 human L1 elements are thought to be active in the genome. The mobilization of these active elements may be influenced upon exposure to the heavy metals. In the present study, we evaluated the association of aluminum, lead, and copper exposure with L1 retrotransposition in human hepatocellular carcinoma (HepG2) cell line. An in vitro retrotransposition assay using an enhanced green fluorescent protein (EGFP)-tagged L1RP cassette was established to track EGFP shining as the mark of retrotransposition. Following determination of noncytotoxic concentrations of these metals, pL1RP-EGFP-transfected HepG2 cells were subjected to long-term treatment. Flow cytometry analysis of cells treated with various concentrations of these metals along with quantitative real-time PCR was used to quantify L1 retrotransposition frequencies. Aluminum significantly increased L1 retrotransposition frequency, while no significant association was found concerning lead exposure and L1 retrotransposition. Copper treatment downregulated L1 retrotransposition as a result of EGFP-tagged L1RP expression. Our findings suggest that aluminum might have the potential to cause genomic instability by the enhancement of L1 mobilization. Thus, the risk of induced L1 retrotransposition should be considered during drug safety evaluation and risk assessments of exposure to toxic environmental agents. Further studies are needed for a more robust assay to evaluate any associations between long-term lead exposure and L1 mobility in cell culture assay.