Mortality and prognostic factors for spontaneous pneumothorax in older adults.

Spontaneous pneumothorax occurs predominantly in young males and older adults, often as a secondary condition, and can be refractory and fatal. This study aimed to investigate the mortality and prognostic factors for pneumothorax in older patients. We retrospectively cohort studied patients with pneumothorax aged ≥65 years who visited our department from October 2012 to January 2019. Data on sex, age, medical history, smoking history, underlying lung disease, treatment, and prognosis were extracted from medical records. Cox proportional hazards regression analysis was used to investigate pneumothorax mortality and prognostic factors. In total, 239 patients were included. Among them, 36 (15%) died during hospitalization. Respiratory disease was the direct cause of death in 30 patients (83.3%), and 211 (88.3%) patients had underlying lung disease. The incidence of pneumonia in our hospital was 22.6% (54 cases). On admission, the mortality rate was 33% (18/54) in patients with concomitant pneumonia; univariate analysis showed significant differences in the Charlson Comorbidity Index (CCI), activities of daily living (ADL), and concomitant pneumonia. In the Cox proportional hazards analysis of ADL (p = 0.09), CCI (p = 0.05), and concomitant pneumonia on admission (p = 0.02), concomitant pneumonia on admission was found to be an independent predictor of in-hospital mortality. This study suggests that concomitant pneumonia at admission may be a mortality risk factor for pneumothorax.

Evaluation of Apparent Noise on CT Images Using Moving Average Filters.

This study aims to devise a simple method for evaluating the magnitude of texture noise (apparent noise) observed on computed tomography (CT) images scanned at a low radiation dose and reconstructed using iterative reconstruction (IR) and deep learning reconstruction (DLR) algorithms, and to evaluate the apparent noise in CT images reconstructed using the filtered back projection (FBP), IR, and two types of DLR (AiCE Body and AiCE Body Sharp) algorithms. We set a square region of interest (ROI) on CT images of standard- and obese-sized low-contrast phantoms, slid different-sized moving average filters in the ROI vertically and horizontally in steps of 1 pixel, and calculated the standard deviation (SD) of the mean CT values for each filter size. The SD of the mean CT values was fitted with a curve inversely proportional to the filter size, and an apparent noise index was determined from the curve-fitting formula. The apparent noise index of AiCE Body Sharp images for a given mAs value was approximately 58, 23, and 18% lower than that of the FBP, AIDR 3D, and AiCE Body images, respectively. The apparent noise index was considered to reflect noise power spectrum values at lower spatial frequency. Moreover, the apparent noise index was inversely proportional to the square roots of the mAs values. Thus, the apparent noise index could be a useful indicator to quantify and compare texture noise on CT images obtained with different scan parameters and reconstruction algorithms.

PATIENT-SPECIFIC ORGAN DOSE EVALUATION BASED ON MONTE CARLO SIMULATION AND DOSE METRICS IN PAEDIATRIC CHEST-ABDOMEN-PELVIS CT EXAMINATIONS.

This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual paediatric patients undergoing chest-abdomen-pelvis computed tomography (CT) examinations and to evaluate correlations of organ doses with dose metrics. MC simulations were performed by inputting detailed descriptions of a CT scanner, scanning parameters and CT images of 51 paediatric patients aged from 0 to 10 years into the simulation software. Organ doses for six radiosensitive organs were determined from dose distribution images obtained as the simulation results. The correlations of organ doses with dose metrics such as volume CT dose index, size-specific dose estimates (SSDEs), and organ-specific SSDEs were evaluated from the corresponding coefficients of determination. Organ doses for ages of 0-1 and 1-5 years were 22%-32% lower than those for ages of 5-10 years. Organ doses exhibited higher linear correlations with SSDEs and organ-specific SSDEs, and can be easily estimated using the linear regression.

Radiation Dose Reduction for Computed Tomography Localizer Radiography Using an Ag Additional Filter.

OBJECTIVE: This study aimed to assess the potential of an Ag additional filter attached to the bow tie filter of a computed tomography (CT) scanner to reduce the radiation dose in CT localizer radiography. METHODS: Radiation doses in CT localizer radiography with Cu and Ag additional filters were evaluated based on dose measurements and Monte Carlo simulations. Image quality evaluations of an adult torso phantom were performed, and the automatic exposure control performance was evaluated in terms of the water-equivalent thickness estimated from CT localizer radiographs. RESULTS: With the Ag additional filter, effective doses were approximately 72% to 75% lower than those with the Cu additional filter. The image quality and water-equivalent thickness with the Ag additional filter were similar to those with the Cu additional filter. CONCLUSIONS: The Ag additional filter helped significantly reduce radiation doses in CT localizer radiography while maintaining image quality and performance.

Correlation analysis of organ doses determined by Monte Carlo simulation with dose metrics for patients undergoing chest-abdomen-pelvis CT examinations.

OBJECTIVES: This study aimed to determine organ doses based on Monte Carlo (MC) simulations for individual patients undergoing routine adult chest abdomen-pelvis computed tomography (CT) examinations and to evaluate the correlations of organ doses with patient size and dose metrics. METHODS: MC simulations were performed by reading detailed descriptions of the CT scanner, scanning parameters, and CT images of phantoms and patients into the simulation software. The simulation models were validated by comparing the simulated doses with the doses measured by in-phantom dosimetry using radiophotoluminescent glass dosimeters and an adult anthropomorphic phantom, and organ doses for 80 patients were determined from the simulation results. To obtain patient size and dose metrics, body mass index and volume computed tomography dose index (CTDIvol) data were collected. Water equivalent diameter (WED) was calculated from the CT images of each patient. Size-specific dose estimates (SSDE) were calculated using CTDIvol and average WED over the scan range, and organ specific SSDE were calculated using the average CTDIvol and WED over each organ position. The correlations of organ doses with dose metrics were evaluated using coefficients of determination. RESULTS: Organ doses increased with patient size, and the doses for obese were approximately two to three times higher than those for underweight patients. Organ doses exhibited stronger linear relationships with organ specific SSDE (R2 ≥ 0.82) than other dose metrics. CONCLUSIONS: The linear regression fits between organ doses determined by MC simulation and organ-specific SSDE are valuable for simplified and accurate organ dose estimation for individual patients undergoing CT examinations.

Treatment and comorbidities of multiple sclerosis in an employed population in Japan: analysis of health claims data.

AIM: Use real-world data to investigate the treatment, comorbidities and prevalence of multiple sclerosis (MS) in an employed Japanese population. METHODS: Data from the Japanese Medical Data Center health insurance claims database were analyzed (January 2005-November 2014). Patients with claims associated with an MS diagnosis were identified (n = 494) and comorbidities and prescribed treatments were investigated. MS prevalence within the database was calculated for each calendar year (2011-2013) Results: IFN-ß and prednisolone were the most commonly prescribed treatments. Common comorbidities included astigmatism and gastric ulcer. Within the database, MS prevalence increased from 0.015 to 0.016%. CONCLUSION: MS prevalence increased from 2011 to 2013. Some comorbidities were considered unrelated to MS owing to how physicians use disease codes for reimbursement.

Discovery of the first potent and orally available agonist of the orphan G-protein-coupled receptor 52.

G-protein-coupled receptor 52 (GPR52) is an orphan Gs-coupled G-protein-coupled receptor. GPR52 inhibits dopamine D2 receptor signaling and activates dopamine D1/N-methyl-d-aspartate receptors via intracellular cAMP accumulation, and therefore, GPR52 agonists may have potential as a novel class of antipsychotics. A series of GPR52 agonists with a bicyclic core was designed to fix the conformation of the phenethyl ether moiety of compounds 2a and 2b. 3-[2-(3-Chloro-5-fluorobenzyl)-1-benzothiophen-7-yl]-N-(2-methoxyethyl)benzamide 7m showed potent activity (pEC50 = 7.53 ± 0.08) and good pharmacokinetic properties. Compound 7m significantly suppressed methamphetamine-induced hyperactivity in mice after oral administration of 3 mg/kg without disturbance of motor function.

Automated DNA extraction from genetically modified maize using aminosilane-modified bacterial magnetic particles.

A novel, automated system, PNE-1080, equipped with eight automated pestle units and a spectrophotometer was developed for genomic DNA extraction from maize using aminosilane-modified bacterial magnetic particles (BMPs). The use of aminosilane-modified BMPs allowed highly accurate DNA recovery. The (A(260)-A(320)):(A(280)-A(320)) ratio of the extracted DNA was 1.9+/-0.1. The DNA quality was sufficiently pure for PCR analysis. The PNE-1080 offered rapid assay completion (30 min) with high accuracy. Furthermore, the results of real-time PCR confirmed that our proposed method permitted the accurate determination of genetically modified DNA composition and correlated well with results obtained by conventional cetyltrimethylammonium bromide (CTAB)-based methods.

Single nucleotide mismatch analysis using oligonucleotide probes synthesized on bacterial magnetic particle.

An approach to analyze mismatches using short and specific oligonucleotide probes directly synthesized on bacterial magnetic particles (BMPs) by phosphoramidite methods was exploited. Approximately 126 molecules of 4-mer oligonucleotides/particle were synthesized on BMPs with high reaction efficiencies. Hybridization between FITC-labeled oligonucleotides and chemically synthesized oligonucleotides on BMPs was performed. Perfect matched and mismatched hybridizations were successfully discriminated by using the oligonucleotide probes on BMPs.

Rapid discovery and identification of a tissue-specific tumor biomarker from 39 human cancer cell lines using the SELDI ProteinChip platform.

Useful biomarkers are needed for early detection of cancers. To demonstrate the potential diagnostic usefulness of a new proteomic technology, we performed Expression Difference Mapping analysis on 39 cancer cell lines from 9 different tissues using ProteinChip technology. A protein biomarker candidate of 12kDa was found in colon cancer cells. We then optimized the purification conditions for this biomarker by utilizing Retentate Chromatography mass spectrometry (RC-MS). The optimized purification conditions developed "on-chip" were directly transferred to conventional chromatography to purify the biomarker, which was identified as prothymosin-alpha by ProteinChip time-of-flight mass spectrometry (TOF MS) and ProteinChip-Tandem MS systems. The relative expression level of prothymosin-alpha between colon cancer cells and normal colon mucosal cells was evaluated on the same ProteinChip platform. Prothymosin-alpha expression in colon cancer cells was clearly higher than in normal colon cells. These results indicate that prothymosin-alpha could be a potential biomarker for colon cancer, and that the ProteinChip platform could perform the whole process of biomarker discovery from screening to evaluation of the identified marker.

SNP detection in transforming growth factor-beta1 gene using bacterial magnetic particles.

A single nucleotide polymorphism (SNP) within the transforming growth factor-beta1 (TGF-beta1) gene was detected by hybridization-based method using bacterial magnetic particles (BMPs). TGF-beta1 is commonly associated with a single base change resulting in a Leu(10)-->Pro (T(869)-->C) polymorphism and is a genetic marker for susceptibility to osteoporosis. Short (9 bases) and specific probes were designed to detect SNP in TGF-beta1. Detection probes were immobilized on BMPs using cross-linking reagents. TGF-beta1 PCR products (139 bp) were labeled with the fluorescent dye coumarin and hybridized with detection probes on BMPs. Complementary hybridized targets gave over four times higher fluorescent intensities, compared with one base mismatched hybridizations. The SNP genotype was successfully discriminated using this technique.