Estimating cancer induction risk from abdominopelvic scanning with 6- and 16-slice computed tomography

Purpose: The biological effects of ionizing radiation (BEIR VII) report estimates that the risk of getting cancer from radiation is increased by about a third from current regulation risk levels. The propose of this study was to estimate cancer induction risk from abdominopelvic computed tomography (CT) scanning of adult patients using 6- and 16-slice CT scanners.

Materials and methods: A cross-sectional study on 200 patients with abdominopelvic CT scan in 6- and 16-slice scanners was conducted. The dose-length product (DLP) and volume CT Dose Index (CTDI_vol) values from the scanners as well as the effective dose values from the ImPACT CT patient dosimetry calculator with the biological effects of ionizing radiation (BEIR VII) method were used to estimate the cancer induction risk.

Results: The mean (and standard deviation) values of CTDI_vol and DLP were 6.9 (±1.07) mGy and 306.44 (±?60.57) mGy.cm for 6-slice, and 5.19 (±0.91) mGy and 219.7 (±49.31) mGy.cm for 16-slice scanner, respectively. The range of effective dose in the 6-slice scanner was 2.61–8.15 mSv and, in the 16-slice scanner, it was 1.47–4.72 mSv. The mean and standard deviation values of total cancer induction risk in abdominopelvic examinations were 0.136?±?0.059% for men and 0.135?±?0.063% for women in the 6-slice CT scanner. The values were 0.126?±?0.051% for men and 0.127?±?0.056% for women in the 16-slice scanner.

Conclusions: The cancer induction risk of abdominopelvic scanning was noticeable. Therefore, radiation dose should be minimized by optimizing the protocols and applying appropriate methods.     

A randomized,triple masked,placebo-controlled clinical trial for controlling childhood obesity

Background  

The efficacy of pharmacological treatment in controlling childhood obesity is controversial. We aimed to compare the effects of three types of drug regimens and placebo on generalized and abdominal obesity among obese children and adolescents who did not succeed to lose weight 3 months after lifestyle modification (diet and exercise).     

Surface fluids effects on the bladder tissue characterisation using electrical impedance spectroscopy

The electrical impedance of the human urinary bladder in both benign and malignant areas can be measured using an electrical impedance spectroscopy system (EIS). Glycine is usually used in the bladder surgery in the theatre to make an insulation medium for electro-surgery and the extension of the mucosa. In addition, a saline solution is usually used to wash the inside of the bladder after bladder surgery and it is used to extend the bladder tissue mucosa. Therefore, the effect of glycine and the saline solution that fills the bladder is important, because it was expected that the application of common surface fluids (air, saline solution and glycine solution) in the bladder epithelium would affect the measured electrical impedance of the urothelium, to differentiate the malignant area from the normal bladder tissue. In this study, bladders were removed from the patients' bodies and then were moved from theatre to the histopathology department immediately after excision. These bladder samples were then opened and pinned to a corkboard to take the impedance readings, using the impedance spectroscopy system. Following this, the bladder and corkboard were completely submerged in a saline solution and readings were taken at about 1cm from the sutures. Subsequently, this procedure was repeated with the bladder submerged in glycine and then air, respectively. According to the statistical work, these fluids were found to have a significant effect on the measured impedance of the bladder tissue in benign and malignant areas. Furthermore, the best fluid between air, glycine and saline, to measure the impedance of the urinary bladder, is air (P<0.0001).     

TOX provides a link between calcineurin activation and CD8 lineage commitment

T cell development is dependent on the integration of multiple signaling pathways, although few links between signaling cascades and downstream nuclear factors that play a role in thymocyte differentiation have been identified. We show here that expression of the HMG box protein TOX is sufficient to induce changes in coreceptor gene expression associated with beta-selection, including CD8 gene demethylation. TOX expression is also sufficient to initiate positive selection to the CD8 lineage in the absence of MHC-TCR interactions. TOX-mediated positive selection is associated with up-regulation of Runx3, implicating CD4 silencing in the process. Interestingly, a strong T cell receptor-mediated signal can modify this cell fate. We further demonstrate that up-regulation of TOX in double positive thymocytes is calcineurin dependent, linking this critical signaling pathway to nuclear changes during positive selection.     

Factors affecting the release of nifedipine from a swellable elementary osmotic pump

Oral osmotic devices including an elementary osmotic pump (EOP) are efficient systems for the delivery of drugs with high/moderately water-solubility. In this study we designed a new type of EOP for the efficient delivery of poorly water-soluble and practically insoluble drugs. In this system, called swellable elementary osmotic pump (SEOP), drug is released from the delivery orifice in the form of a very fine dispersion of drug in gel which is ready for dissolution and absorption. Factors affecting the release of drug from the SEOP containing a poorly water-soluble drug, nifedipine, were explored extensively. To this end, effect of swelling and wetting agents, orifice size, concentration of osmotic agent, and hydrophobic plasticizer were investigated. Interestingly, in the absence or low concentration of a hydrophobic plasticizer (caster oil), the osmotic devices did not retain their integrity in dissolution media. Caster oil in concentration of > 1% was necessary for tablets to retain their integrity during dissolution process. A zero-order release kinetics for nifedipine was achieved following the effective optimization of the concentrations of swelling agent, osmotic agent, wetting agent, and also size of orifice and membrane thickness in SEOP. The zero-order release lasted for 10 hr at pH 6.8 dissolution medium. The designed SEOP is suggested as an efficient controlled delivery system for oral delivery of a poorly water soluble drug such as nifedipine.     

Globin chain synthesis is a useful complementary tool in the differential diagnosis of thalassemias

The present study aimed at differentiating rare types of heterozygous beta-thalassemia (thal) with normal Hb A(2) values from alpha-thal in Iranian carriers by globin chain synthesis in addition to other hematological parameters. Our study groups consisted of 51 normal subjects, 24 heterozygous beta- thalassemic subjects with high Hb A(2), 62 alpha-thal-2 subjects, 34 alpha-thal-1 subjects, six Hb H disease thalassemic subjects, 14 silent beta-thal subjects with normal Hb A(2) values, five deltabeta-thal subjects and two subjects with an association of alpha- and deltabeta-thal (total = 198). Analysis of globin chains was performed by high performance liquid chromatography (HPLC). The results showed that the alpha/beta ratio averages were close to the ones in the published literature, but with a greater standard deviation and a wider range. Globin chain synthesis (GCS) could be valuable in differentiating between microcytosis produced by silent beta-thal (heterozygous beta-thal with a normal Hb A(2) level) and that caused by alpha-thal. Since the complex genotype/phenotype relationship can lead to diagnostic difficulties, GCS cannot be used as the only diagnostic tool for thalassemia carrier detection. Therefore, a combination of different tests for each patient is required.