Iodine quantification with dual-energy CT: phantom study and preliminary experience with VX2 residual tumour in rabbits after radiofrequency ablation

OBJECTIVE

The purpose of our study was to validate iodine quantification in a phantom study with dual-source dual-energy CT (DECT) and to apply this technique to differentiate benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after radiofrequency ablation (RFA).

METHODS

We applied iodine quantification with DECT in a phantom and in VX2 carcinoma in rabbits after incomplete RFA to differentiate benign periablational reactive tissue from residual tumour and evaluated its efficacy in demonstrating response to therapeutic RFA. A series of tubes containing solutions of varying iodine concentration were scanned with DECT. The iodine concentration was calculated and compared with known true iodine concentration. Triple-phase contrast-enhanced DECT data on 24 rabbits with VX2 carcinoma were then assessed at Day 3 (n=6), 1 week (n=6), 2 weeks (n=6) and 3 weeks (n=6) after incomplete RFA independently by 2 readers. Dual-energy postprocessing was used to produce iodine-only images. Regions of interest were positioned on the iodine image over the lesion and, as a reference, over the aorta, to record iodine concentration in the lesion and in the aorta. The pathological specimens were sectioned in the same plane as DECT imaging, and the lesion iodine concentration and lesion-to-aorta iodine ratio of residual tumour and benign periablational reactive tissue were assessed.

RESULTS

There was excellent correlation between calculated and true iodine concentration (r=0.999, p<0.0001) in the phantom study. The lesion iodine concentration and lesion-to-aorta iodine ratio in residual tumour were significantly higher than in benign periablational reactive tissue in the 2-week group during the arterial phase (AP) (p<0.01) and in the 3-week group during both the AP (p<0.05) and the portal venous phase (p<0.05). There was no significant difference between them with respect to the lesion iodine concentration or lesion-to-aorta iodine ratio in the 3-day and 1-week groups.

CONCLUSION

Iodine quantification with DECT is accurate in a phantom study and can be used to differentiate benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after RFA.

ADVANCES IN KNOWLEDGE

Iodine quantification with DECT may help in differentiating benign periablational reactive tissue from residual tumour in VX2 carcinoma in rabbits after RFA.

Effects of ischemic preconditioning in the late phase on homing of endothelial progenitor cells in renal ischemia/reperfusion injury

OBJECTIVE

The aim of this study was to determine whether the mobilization and recruitment of endothelial progenitor cells (EPCs) contribute to the protection of kidneys from ischemia/reperfusion (I/R) injury after ischemic preconditioning (IPC) during the late phase.

METHODS

Seventy-five male Sprague-Dawley rats were divided into the following groups: sham-operated (group A; n = 25), ischemia/reperfusion hosts that underwent 45 minutes of left renal artery ischemia (group B; n = 25), and ischemic preconditioning-treated group (group C; n = 25). Group C underwent 3 cycles of 5 minutes of occlusion and 5 minutes of reperfusion followed by 24 hours of reperfusion before the following 45 minutes of occlusion. Serum samples were collected and renal tissues harvested for histological examination terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, immunohistochemical staining, and Western blot analysis to determine the expression levels of CD34, VEGFR-2 (Vascular Endothelial Growth Factor Receptor 2)/flk-1, vascular endothelial growth factor (VEGF), and stromal cell-derived factor-1α (SDF-1α).

RESULTS

Compared with group B, the levels of blood urea nitrogen (BUN), serum creatinine (Scr) and acute tubulointerstitial injury at 24 hours after operation were significantly reduced in group C. At 72 hours, tubular epithelial cell apoptosis was also decreased (17.6 ± 4.45 vs 63.8 ± 6.10; P < .01). CD34+ and flk-1+ cells that mostly accumulated in the medullopapillary parenchyma were significantly increased at 72 hours (P < .05). Expression levels of VEGF and SDF-1α were also significantly higher in group C (P < .05).

CONCLUSION

The present work suggested that IPC protected kidneys from IR injury in the later phase through enhanced mobilization and recruitment of EPCs. VEGF and SDF-1α may play important roles in this protective effect.

A peptide that inhibits function of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS) reduces lung cancer metastasis

Myristoylated Alanine-Rich C Kinase Substrate (MARCKS), a substrate of protein kinase C, is a key regulatory molecule controlling mucus granule secretion by airway epithelial cells as well as directed migration of leukocytes, stem cells and fibroblasts. Phosphorylation of MARKCS may be involved in these responses. However, the functionality of MARCKS and its related phosphorylation in lung cancer malignancy have not been characterized. This study demonstrated elevated levels of MARCKS and phospho-MARCKS in highly invasive lung cancer cell lines and lung cancer specimens from non-small-cell lung cancer patients. siRNA knockdown of MARCKS expression in these highly invasive lung cancer cell lines reduced cell migration and suppressed PI3K (phosphatidylinositol 3'-kinase)/Akt phosphorylation and Slug level. Interestingly, treatment with a peptide identical to the MARCKS N-terminus sequence (the MANS peptide) impaired cell migration in vitro and also the metastatic potential of invasive lung cancer cells in vivo. Mechanistically, MANS peptide treatment resulted in a coordination of increase of E-cadherin expression, suppression of MARCKS phosphorylation and AKT/Slug signalling pathway but not the expression of total MARCKS. These results indicate a crucial role for MARCKS, specifically its phosphorylated form, in potentiating lung cancer cell migration/metastasis and suggest a potential use of MARCKS-related peptides in the treatment of lung cancer metastasis.

Anti-tumour necrosis factor therapy enhances mucosal healing through down-regulation of interleukin-21 expression and T helper type 17 cell infiltration in Crohn's disease

Anti-tumour necrosis factor (TNF) monoclonal antibody (mAb) (infliximab, IFX) has been shown to be highly effective in the management of Crohn's disease (CD). Herein we investigated the potential role of IFX in inducing clinical remission and regulating interleukin (IL)-21 expression and T helper type 17 (Th17) cell infiltration in the intestinal mucosa of CD patients. Twenty-six CD patients were treated with IFX at weeks 0, 2 and 6. Clinical response, mucosal healing, serum C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were evaluated at week 10 after IFX administration. Expression of IL-21, IL-17A and retinoic acid-related orphan receptor C (RORC) in intestinal mucosa were analysed by quantitative real-time polymerase chain reaction (PCR) and immunohistochemistry. Peripheral blood and lamina propria CD4(+) T cells were stimulated with anti-CD3 and anti-CD28 mAbs in the presence of IFX. Cytokine profiles and RORC were determined with enzyme-linked immunosorbent assay (ELISA) and real-time PCR. IL-21 and Th17 cells were found to be expressed highly in inflamed mucosa of active CD patients compared with healthy controls. Ten weeks after IFX infusion, CD activity index, ESR, CRP and intestinal mucosal healing were improved markedly in CD patients, and IL-21 expression and Th17 cell infiltration were decreased significantly compared with those before IFX therapy. In-vitro study demonstrated that IFX treatment could suppress IL-21, IL-17A and RORC expression in cultured CD biopsies. Moreover, IFX was also observed to down-regulate markedly IL-17A, IL-21 and RORC expression by CD CD4(+) T cells. IFX is highly effective in inducing clinical remission and promoting intestinal mucosal healing in CD patients through down-regulation of IL-21 expression and Th17 cell infiltration in intestinal mucosa.

Deletion of ATG5 shows a role of autophagy in salivary homeostatic control

Autophagy is a catabolic pathway utilized to maintain a balance among the synthesis, degradation, and recycling of cellular components, thereby playing a role in cell growth, development, and homeostasis. Previous studies revealed that a conditional knockout of essential member(s) of autophagy in a variety of tissues causes changes in structure and function of these tissues. Acinar cell-specific expression of knocked-in Cre recombinase through control of aquaporin 5 (Aqp5) promoter/enhancer (Aqp5-Cre) allows us to specifically inactivate Atg5, a protein necessary for autophagy, in salivary acinar cells of Atg5(f/f);Aqp5-Cre mice. There was no difference in apoptotic or proliferation levels in salivary glands of Atg5/Cre mice from each genotype. However, H&E staining and electron microscopy studies revealed modestly enlarged acinar cells and accumulated secretory granules in salivary glands of Atg5(f/f);Aqp5-Cre mice. Salivary flow rates and amylase contents of Atg5/Cre mice indicated that acinar-specific inactivation of ATG5 did not alter carbachol-evoked saliva and amylase secretion. Conversely, autophagy intersected with salivary morphological and secretory manifestations induced by isoproterenol administration. These results identified a role for autophagy as a homeostasis control in salivary glands. Collectively, Atg5(f/f);Aqp5-Cre mice would be a useful tool to enhance our understanding of autophagy in adaptive responses following targeted head and neck radiation or Sjögren syndrome.

Mapping shape quantitative trait loci using a radius-centroid-contour model

As the consequence of complex interactions between different parts of an organ, shape can be used as a predictor of structural-functional relationships implicated in changing environments. Despite such importance, however, it is no surprise that little is known about the genetic detail involved in shape variation, because no approach is currently available for mapping quantitative trait loci (QTLs) that control shape. Here, we address this problem by developing a statistical model that integrates the principle of shape analysis into a mixture-model-based likelihood formulated for QTL mapping. One state-of-the-art approach for shape analysis is to identify and analyze the polar coordinates of anatomical landmarks on a shape measured in terms of radii from the centroid to the contour at regular intervals. A procrustes analysis is used to align shapes to filter out position, scale and rotation effects on shape variation. To the end, the accurate and quantitative representation of a shape is produced with aligned radius-centroid-contour (RCC) curves, that is, a function of radial angle at the centroid. The high dimensionality of the RCC data, crucial for a comprehensive description of the geometric feature of a shape, is reduced by principal component (PC) analysis, and the resulting PC axes are treated as phenotypic traits, allowing specific QTLs for global and local shape variability to be mapped, respectively. The usefulness and utilization of the new model for shape mapping in practice are validated by analyzing a mapping data collected from a natural population of poplar, Populus szechuanica var tibetica, and identifying several QTLs for leaf shape in this species. The model provides a powerful tool to compute which genes determine biological shape in plants, animals and humans.

Odor representation in the olfactory bulb under different brain states revealed by intrinsic optical signals imaging

The olfactory system responds to the same stimulus with great variability according to the current state of the brain. At the levels of multi-unit activity and local field potentials, the response of the olfactory bulb (OB) to a given olfactory stimulus during a state of lower background activity is stronger than the response that occurs during higher background activity, but the distribution pattern of activity remains similar. However, these results have only been established at the individual neuron and neuron cluster scales in previous studies. It remains unclear whether these results are consistent at a larger scale (e.g., OB regions); therefore, intrinsic optical signals imaging was employed in the present study to clarify this issue. The basal brain states of rats were manipulated by using different levels of anesthesia. Under a state of low basal brain activity, the intensity of the activity pattern elicited in the dorsal OB by a given odorant was significantly higher than that under high basal brain activity, but the topography was highly similar across different brain states. These results were consistent across the levels of individual neurons, neuron clusters, glomeruli, and the OB regions, which suggest that the OB contains as yet unknown neural mechanisms that ensure the high-fidelity representation of the same olfactory stimulation under different brain states.

Insight into the sporulation phosphorelay: crystal structure of the sensor domain of Bacillus subtilis histidine kinase, KinD

The Bacillus subtilis KinD signal-transducing histidine kinase is a part of the sporulation phosphorelay known to regulate important developmental decisions such as sporulation and biofilm formation. We have determined crystal structures of the extracytoplasmic sensing domain of KinD, which was copurified and crystallized with a pyruvate ligand. The structure of a ligand-binding site mutant was also determined; it was copurified and crystallized with an acetate ligand. The structure of the KinD extracytoplasmic segment is similar to that of several other sensing domains of signal transduction proteins and is composed of tandem Per-Arnt-Sim (PAS)-like domains. The KinD ligand-binding site is located on the membrane distal PAS-like domain and appears to be highly selective; a single mutation, R131A, abolishes pyruvate binding and the mutant binds acetate instead. Differential scanning fluorimetry, using a variety of monocarboxylic and dicarboxylic acids, identified pyruvate, propionate, and butyrate but not lactate, acetate, or malate as KinD ligands. A recent report found that malate induces biofilm formation in a KinD-dependent manner. It was suggested that malate might induce a metabolic shift and increased secretion of the KinD ligand of unknown identity. The structure and binding assays now suggests that this ligand is pyruvate and/or other small monocarboxylic acids. In summary, this study gives a first insight into the identity of a molecular ligand for one of the five phosphorelay kinases of B. subtilis.

CASP-9 gene functional polymorphisms and cancer risk: a large-scale association study plus meta-analysis

We investigated the association between CASP-9 polymorphisms and susceptibility to neoplasm. Fourteen studies with a total of 2733 neoplasm cases and 3352 healthy controls were included. Meta-analysis showed that the rs4645981 T allele and the rs4645981 T allele carrier were positively associated with neoplasm susceptibility [odds ratio (OR) = 1.43, 95% confidence interval (95%CI) = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009, respectively]. However, the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might decrease the risk of cancer (OR = 0.72, 95%CI = 0.58-0.89, P = 0.003; OR = 0.76, 95%CI = 0.63-0.92, P = 0.004; OR = 0.20, 95%CI = 0.09-0.45, P < 0.0001; OR = 0.21, 95%CI = 0.06-0.75, P = 0.02, respectively). There was no significant association between rs1263, rs1052571, rs2308950, rs4645978, rs4645980, rs4645982, and rs4646018 and cancer risk (all P > 0.05). In conclusion, this meta-analysis suggests that CASP-9 gene polymorphisms are involved in the pathogenesis of various cancers. The rs4645981 T allele and the rs4645981 T allele carrier might increase the risk of cancer, but the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might be protective.

Exome sequencing-driven discovery of coding polymorphisms associated with common metabolic phenotypes

AIMS/HYPOTHESIS

Human complex metabolic traits are in part regulated by genetic determinants. Here we applied exome sequencing to identify novel associations of coding polymorphisms at minor allele frequencies (MAFs) >1% with common metabolic phenotypes.

METHODS

The study comprised three stages. We performed medium-depth (8×) whole exome sequencing in 1,000 cases with type 2 diabetes, BMI >27.5 kg/m(2) and hypertension and in 1,000 controls (stage 1). We selected 16,192 polymorphisms nominally associated (p < 0.05) with case-control status, from four selected annotation categories or from loci reported to associate with metabolic traits. These variants were genotyped in 15,989 Danes to search for association with 12 metabolic phenotypes (stage 2). In stage 3, polymorphisms showing potential associations were genotyped in a further 63,896 Europeans.

RESULTS

Exome sequencing identified 70,182 polymorphisms with MAF >1%. In stage 2 we identified 51 potential associations with one or more of eight metabolic phenotypes covered by 45 unique polymorphisms. In meta-analyses of stage 2 and stage 3 results, we demonstrated robust associations for coding polymorphisms in CD300LG (fasting HDL-cholesterol: MAF 3.5%, p = 8.5 × 10(-14)), COBLL1 (type 2 diabetes: MAF 12.5%, OR 0.88, p = 1.2 × 10(-11)) and MACF1 (type 2 diabetes: MAF 23.4%, OR 1.10, p = 8.2 × 10(-10)).

CONCLUSIONS/INTERPRETATION

We applied exome sequencing as a basis for finding genetic determinants of metabolic traits and show the existence of low-frequency and common coding polymorphisms with impact on common metabolic traits. Based on our study, coding polymorphisms with MAF above 1% do not seem to have particularly high effect sizes on the measured metabolic traits.

Meta-analysis demonstrates association of XRCC1 genetic polymorphism Arg399Gln with esophageal cancer risk in the Chinese population

We made a meta-analysis of the association between X-ray cross-complementing gene 1 (XRCC1) genetic polymorphism Arg399Gln and esophageal cancer (EC) risk. Statistical analysis was performed with the Review Manager version 4.2.8 software program and STATA version 11.0. We selected 16 case-control studies for this meta-analysis, including 3591 EC cases and 5752 controls. Overall, the Gln399 allele was not associated with EC risk, compared with the Arg399 allele in the populations included in the analysis. However, stratified analysis revealed that the Gln399 allele was associated with increased EC risk among the Chinese population in a recessive model [odds ratio (OR) = 1.42; 95% confidence interval (95%CI) = 1.07-1.90; P = 0.02 for heterogeneity] and by homozygote contrast (OR = 1.43; 95%CI = 1.05-1.96; P = 0.02 for heterogeneity), particularly for the tumor histology of squamous cell carcinoma (OR = 1.46; 95%CI = 1.10-1.95 for the recessive model and OR = 1.42; 95%CI = 1.03-1.95 for the homozygote contrast). We conclude that the XRCC1 Arg399Gln polymorphism has potential as a biomarker for EC susceptibility in the Chinese population, particularly for squamous cell carcinoma.

A literature-based systematic HuGE review and meta-analysis show that CASP gene family polymorphisms are associated with risk of lung cancer

The caspase (CASP) gene family is known to be involved in apoptosis, cytokine maturation, cell growth, and differentiation. A large number of single nucleotide polymorphisms (SNPs) in the CASP gene family have been increasingly recognized as important regulators in the development of lung cancer. However, this specific association is still controversial. In this Human Genome Epidemiology review and meta-analysis, we summarized the available evidence associating lung cancer with the CASP gene family. Seven studies, which included 1155 lung cancer cases and 1120 healthy controls, met the inclusion criteria and were included in our meta-analysis. In seven studies, 19 different SNPs have been studied in seven CASP genes, including CASP-1, -2, -5, -7, -8, -9, and -10. Meta-analysis results showed positive associations between heterozygote (A/G) of rs507879 in the CASP-5 gene, the T allele of rs12415607 in the CASP-7 gene, and the T allele and T carrier (C/T+T/T) of rs4645981 in the CASP-9 gene with lung cancer susceptibility [odds ratio (OR) = 1.83, 95% confidence interval (95%CI) = 1.07-3.12, P = 0.03; OR = 1.18, 95%CI = 1.02-1.37, P = 0.03; OR = 1.43, 95%CI = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009; respectively]. However, we found that homozygote (G/G) of rs2227310 in the CASP-7 gene, del allele, heterozygote (ins/del), and del carrier (ins/del + del/del) of rs3834129 in CASP-8 could be protective factors for lung cancer (OR = 0.17, 95%CI = 0.14-0.21, P = 0.0003; OR = 0.83, 95%CI = 0.72-0.97, P = 0.02; OR = 0.74, 95%CI = 0.64-0.85, P < 0.0001; OR = 0.81, 95%CI = 0.71-0.93, P = 0.002; respectively). In conclusion, based on this meta-analysis, we suggest that SNPs in CASP-5, -7, -8, and -9 are associated with susceptibility to lung cancer.

Culture of normal human airway epithelial cells and measurement of mucin synthesis and secretion

The plasticity of conducting airway epithelia is well recognized (1-3). Under normal conditions, the epithelia express mucociliary function, which is the first pulmonary defense mechanism against inhaled air pollutants. Aberrance in this function is either the cause or one of the major contributors to the pathogenesis of various pulmonary diseases, such as asthma and bronchitis. To exert this vital defense function, mucus-secreting cell types of surface epithelium and sub- mucosal gland synthesize and secrete a high-mol-wt mucous glycoprotein, mucin, which is responsible for the viscoelastic property of the surface mucus layer. Secreted mucus, which is able to trap air pollutants and microorganisms, is steadily removed from the airway surface by ciliary escalation. Overall, the coordinated mucociliary function helps to maintain homeostasis in airway lumen.

Lung effects of inhaled corticosteroids in a rhesus monkey model of childhood asthma

BACKGROUND

The risks for infants and young children receiving inhaled corticosteroid (ICS) therapy are largely unknown. Recent clinical studies indicate that ICS therapy in pre-school children with symptoms of asthma result in decreased symptoms without influencing the clinical disease course, but potentially affect postnatal growth and development. The current study employs a primate experimental model to identify the risks posed by ICS therapy.

OBJECTIVE

To (1) establish whether ICS therapy in developing primate lungs reverses pulmonary pathobiology associated with allergic airway disease (AAD) and (2) define the impact of ICS on postnatal lung growth and development in primates.

METHODS

Infant rhesus monkeys were exposed, from 1 through 6 months, to filtered air (FA) with house dust mite allergen and ozone using a protocol that produces AAD (AAD monkeys), or to FA alone (Control monkeys). From three through 6 months, the monkeys were treated daily with ICS (budesonide) or saline.

RESULTS

Several AAD manifestations (airflow restrictions, lavage eosinophilia, basement membrane zone thickening, epithelial mucin composition) were reduced with ICS treatment, without adverse effects on body growth or adrenal function; however, airway branching abnormalities and intraepithelial innervation were not reduced. In addition, several indicators of postnatal lung growth and differentiation: vital capacity, inspiratory capacity, compliance, non-parenchymal lung volume and alveolarization, were increased in both AAD and Control monkeys that received ICS treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Incomplete prevention of pathobiological changes in the airways and disruption of postnatal growth and differentiation of airways and lung parenchyma in response to ICS pose risks for developing primate lungs. These responses also represent two mechanisms that could compromise ICS therapy's ability to alter clinical disease course in young children.

Ovine prion protein genotype frequencies in northwestern China

Anti-scrapie breeding programs have been initiated to screen for scrapie-resistant sheep based on ovine prion protein gene (PRNP) genotypes at codons 136, 154 and 171 in many countries, especially European Union member states. However, investigation of sheep PRNP genotypes is limited in China, despite the large number of sheep breeds. We analyzed 432 sheep of five different breeds from farms in northwestern China, using PCR-single-strand conformational polymorphism analysis (PCR-SSCP); the corresponding haplotypes of different PRNP alleles were cloned. PRNP allele genotyping was done by amplification refractory mutation system-PCR (ARMS-PCR), according to the haplotype clones of each PRNP allele. The validity of ARMS-PCR was checked by PCR-SSCP. Another 325 unknown PRNP genotypes of other sheep breeds were analyzed according to the established ARMS-PCR. Genotype frequencies of 757 sheep were analyzed with these two methods to evaluate susceptibility to scrapie in northwestern China. Relevant mutations were also detected at other sites. Both methods were effective for ovine PRNP allele genotyping, and the results of the analysis completely coincided. Scrapie-resistant genotypes were found to be uncommon, indicating a high risk for ovine scrapie in northwest China. In addition to codons 136, 154 and 171, we found numerous new mutations; nearly half of them were previously unreported. These sheep populations have a high degree of polymorphism at the PRNP locus.

Expression and biological relationship of vascular endothelial growth factor-A and matrix metalloproteinase-9 in gastric carcinoma

Protein expression of vascular endothelial growth factor A (VEGF-A) and matrix metalloproteinase 9 (MMP-9) was studied in gastric carcinoma patients in relation to clinicopathological characteristics and prognosis. Fifty-four samples of gastric carcinoma tissue and 15 samples of adjacent normal gastric mucosal tissue were examined immunohistochemically. Expression rates of VEGF-A (66.7%) and MMP-9 (63.0%) in carcinoma tissue were significantly higher than in normal tissue (6.7% for both proteins). VEGF-A and MMP9 expression was associated with tumour size, invasion depth, lymph node metastasis, degree of histological differentiation and pathological stage, but not age or sex. VEGF-A expression was positively correlated with that of MMP-9. Expression of VEGF-A and MMP-9 were each inversely correlated with 5-year survival. VEGF-A and MMP-9 were overexpressed in tumours compared with normal tissue; they may act together to increase carcinogenesis and the progression, invasion and metastasis of gastric carcinoma, and could be used as biomarkers for the prognosis of gastric carcinoma.

Accuracy of high-pitch prospectively ECG-triggering CT coronary angiography for assessment of stenosis in 103 patients: comparison with invasive coronary angiography

AIM

To investigate the accuracy of high-pitch prospectively electrocardiogram (ECG)-triggering low-dose, dual-source computed tomography (CT) coronary angiography for assessing coronary artery stenosis compared with conventional coronary angiography.

MATERIALS AND METHODS

One hundred and three patients undergoing high-pitch CT coronary angiography (CTCA) and conventional coronary angiography (CCA) within 30 days were enrolled. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of high-pitch CTCA for detecting >50 and >70% stenosis were evaluated using CCA as the reference standard on a per-segment, per-vessel, and per-patient basis. Two experienced radiologists independently rated high-pitch CTCA images for quality using a four-point scale (1 = excellent, 4 = non-diagnostic) on a per-segment basis. The effective dose was calculated by multiplying the conversion coefficient of 0.028 by the dose-length product.

RESULTS

The mean heart rate of patients was 57 ± 6 beats/min. For detecting >50% stenosis, the sensitivity, specificity, PPV, and NPV of high-pitch CTCA were 89, 97, 87, and 97% on a per-segment basis; 91, 92, 92, and 91% on a per-vessel basis; and 99, 85, 96, and 94% on a per-patient basis. For detecting >70% stenosis, the sensitivity, specificity, PPV, and NPV of high-pitch CTCA were 96, 98, 90, and 99% on a per-segment basis. Coronary segments were rated as diagnostic in 98.6% (1355/1375) of cases (score 1, 72.5%; score 2, 23.1%; score 3, 3%; score 4, 1.4%). The effective dose of high-pitch CTCA was 1.51 ± 0.31 mSv.

CONCLUSION

High-pitch prospectively ECG-triggering dual-source CTCA provides good image quality and high diagnostic accuracy with a 1.51 mSv radiation dose.

Vitreous surgery for macular hole-related retinal detachment after phacoemulsification cataract extraction: 10-year retrospective review

PURPOSE

To evaluate the visual and anatomical results of surgery for macular hole-related retinal detachment (MHRD) after phacoemulsification cataract extraction.

METHODS

Data for all patients who underwent surgery for MHRD after phacoemulsification cataract extraction from 1 December 1998 to 30 September 2008 in one hospital were evaluated. Patient characteristics, best-corrected visual acuity (VA) preoperatively and at last examination, surgical technique, anatomical success, and follow-up period were extracted and analysed statistically.

RESULTS

A total of 13 625 eyes of 10 076 patients who had phacoemulsification cataract surgery were included. In the follow-up period, 10 cases of MHRD in nine patients were observed, of which seven eyes had high myopia. The mean axial length was 30.97 ± 1.36 mm (29.19, 32.97) and mean myopia was-19.35 ± 1.93 (-7.5,-3.5) dioptres. Overall anatomical success was achieved in 90% (9 out of 10 eyes). There was no statistically significant difference (P=0.240) between the logarithm of the MAR VA before the phacoemulsification cataract extraction and after MHRD surgical repair. VA increased in three eyes but decreased in the other seven after MHRD surgery.

CONCLUSIONS

As a primary procedure, vitreous surgery combined with other necessary adjunct procedures such as membrane peeling and retinal tamponade seems to be successful in achieving anatomical success. However, VA improvement is dependent on the type of macular lesion and not the surgical procedure.

Serum levels of selenium in patients with brain metastases from non-small cell lung cancer before and after radiotherapy

PURPOSE

This study was to evaluate the influence of radiotherapy on the selenium serum levels of non-small cell cancer patients with brain metastases.

PATIENTS AND METHODS

This prospective study included 95 non-small cell cancer patients with brain metastases treated by radiotherapy from December 2007 until November 2010. Plasma selenium levels were determined before and at the end of the radiotherapy. Age, body mass index (BMI), prior chemotherapy, pathological type and personal habits (smoking and alcoholism) were recorded for each patient.

RESULTS

The mean age was 63 years; the mean BMI was 27.6. Seventy-six patients (80%) were non-smokers. Sixty-two patients (65.3%) showed no drinking habits and 8 (8.4%) have no prior chemotherapy. Thirty-nine patients (41.1%) were adenocarcinoma, 51 (53.7%) were squamous cell carcinoma and five (5.3%) were large cell carcinoma. At the beginning of radiotherapy, the mean selenium level for all patients was 90.4 μg/l and after radiation this value dropped to 56.3 μg/l. Multivariate analysis showed statistically significant difference in the plasma selenium concentration before and after radiotherapy for age (P<0.001), BMI (P<0.001), smoking (P<0.001), alcoholism (P<0.001), prior chemotherapy (P<0.001) and pathological type (P<0.001).

CONCLUSION

Significant reduction in plasma levels of selenium was recorded in patients undergoing radiotherapy, suggesting attention to the nutritional status of this micronutrient and other antioxidant agents.