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In this letter, a ray tracing (RT) acceleration method based on the total variation norm minimization (TVNM) scheme is presented. RT is a general tool used to analyze wireless communication environments. However, the simulation is time consuming because of the large number of ray calculations. This letter focuses on radio map interpolation as an acceleration approach. For radio map interpolation, we adopt TVNM, which is a representative edge-preserving interpolation method in the field of image processing. We regard the non-line-of-sight and line-of-sight region boundary as the edge of the radio map and use TVNM to achieve accurate interpolation. Furthermore, we consider known position selection to enhance the interpolation accuracy of TVNM. A computational simulation using commercial RT software revealed that the interpolation accuracy of the proposed method was better than those of other radio map interpolation methods and that RT simulation can be accelerated with an acceptable interpolation error.

Purpose The forced oscillation technique (FOT) is a non-invasive method to measure respiratory impedance, the respiratory resistance (Rrs) and reactance (Xrs). The disease probability measure (DPM) is a useful computed tomography (CT) imaging variable for the assessment of gas trapping and emphysema in patients with chronic obstructive pulmonary disease (COPD) using pairs of inspiratory and expiratory CT images. We aimed to develop FOT-based phenotypes and determine whether the phenotypes and their imaging characteristics could facilitate the understanding of COPD pathophysiology. Patients and methods FOT and spirometry were examined in 164 COPD patients and 22 non-COPD smokers. COPD patients were divided into four FOT-based phenotypes (NL, normal group; RD, resistance-dominant group; XD, reactance-dominant group; and MIX, mixed group) based on the 3rd quartile values of R5 (Rrs at 5Hz) and X5 (Xrs at 5Hz) in the non-COPD group. The emphysematous lesions and the airway lesions were quantitatively assessed in CT images by low attenuation volume and the square root of the wall area of a hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10), respectively. DPM imaging analysis was also performed in 131 COPD patients. We investigated the differences in COPD parameters between the FOT-based phenotypes. Results √Aaw at Pi10 were significantly higher in the RD, XD, and MIX groups than in the NL group. The XD group showed lower pulmonary function and higher dyspnea scores than the RD group. No significant changes in DPM values were observed between the RD and the NL groups. The gas-trapping area was significantly higher in the XD group than in the NL group. The MIX group showed the highest dyspnea score, most emphysematous lesions, and the lowest forced expiratory volume in 1 s % predicted value. Conclusion The FOT-based phenotyping may be useful to assess pathophysiological changes of COPD with CT assessments.

The constraint values of dose-volume histogram (DVH) parameters for radiation pneumonitis (RP) prediction have not been uniform in previous studies. We compared the differences between conventional DVH parameters and DVH parameters with high attenuation volume (HAV) in CT imaging in both esophageal cancer and lung cancer patients to determine the most suitable DVH parameters in predicting RP onset. Seventy-seven and 72 patients who underwent radiation therapy for lung cancer and esophageal cancer, respectively, were retrospectively assessed. RP was valued according to the Common Terminology Criteria for Adverse Events. We quantified HAV with quantitative computed tomography analysis. We compared conventional DVH parameters and DVH parameters with HAV in both groups of patients. Then, the thresholds of DVH parameters that predicted symptomatic RP and the differences in threshold of DVH parameters between lung cancer and esophageal cancer patient groups were compared. The predictive performance of DVH parameters for symptomatic RP was compared using the area under the receiver operating characteristic curve. Mean lung dose, HAV30% (the proportion of the lung with HAV receiving ≥30 Gy), and HAV20% were the top three parameters in lung cancer, while HAV10%, HAV5%, and V10 (the percentage of lung volume receiving 10 Gy or more) were the top three in esophageal cancer. By comparing the differences in the threshold for parameters predicting RP between the two cancers, we saw that HAV30% retained the same value in both cancers. DVH parameters with HAV showed narrow differences in the threshold between the two cancer patient groups compared to conventional DVH parameters. DVH parameters with HAV may have higher commonality than conventional DVH parameters in both patient groups tested.

Background The risk factors for radiation pneumonitis (RP) in patients with chronic obstructive pulmonary disease (COPD) are unclear. Mean lung dose (MLD) and percentage of irradiated lung volume are common predictors of RP, but the most accurate dosimetric parameter has not been established. We hypothesized that the total lung volume irradiated without emphysema would influence the onset of RP. Methods We retrospectively evaluated 100 patients who received radiotherapy for lung cancer. RP was graded according to the Common Terminology Criteria for Adverse Events (version 4.03). We quantified low attenuation volume (LAV) using quantitative computed tomography analysis. The association between RP and traditional dosimetric parameters including MLD, volume of the lung receiving a dose of ≥2 Gy, ≥ 5 Gy, ≥ 10 Gy, ≥ 20 Gy, and ≥30 Gy, and counterpart measurements of the lung without LAV, were analyzed by logistic regression. We compared each dosimetric parameter for RP using multiple predictive performance measures including area under the receiver operating characteristic curve (AUC) and integrated discrimination improvement (IDI). Results Of 100 patients, RP of Grades 1, 2, 3, 4, and 5 was diagnosed in 24, 12, 13, 1, and 1 patients, respectively. Compared with traditional dosimetric parameters, counterpart measurements without LAV improved risk prediction of symptomatic RP. The ratio of the lung without LAV receiving ≥30 Gy to the total lung volume without LAV most accurately predicted symptomatic RP (AUC, 0.894; IDI, 0.064). Conclusion Irradiated lung volume without LAV predicted RP more accurately than traditional dosimetric parameters. Electronic supplementary material The online version of this article (10.1186/s13014-017-0891-z) contains supplementary material, which is available to authorized users.

Introduction: Eosinophilic airway inflammation is now recognized as one of the important pathophysiology of chronic obstructive pulmonary disease (COPD). Objectives: To investigate the usability of fractional exhaled nitric oxide (FeNO) as a maker of eosinophilic inflammation compared with other biomarkers like blood eosinophil counts and serum IgE level in stable COPD patients. Patients and methods: A total of 146 stable COPD patients were enrolled from the outpatient clinic of respiratory medicine in our hospital from May 2011 to June 2016. The patients underwent spirometry and chest CT. FeNO was measured before spirometry. Peripheral blood eosinophil counts and serum IgE level were also measured. Using chest CT data, emphysematous lesions and the airway wall thickness were assessed by the percentage of low attenuation voxels (LAV%) and by the square root of airway wall area of the hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10), respectively. Results: The participants were 10 females and 136 males with a mean age of 71.8 ± 7.3 (mean ± SD) years old. FEV1 %predicted was 68.5 ± 21.2% and FeNO was 29 ± 20 ppb. Laboratory findings showed that blood eosinophils were 237.0 ± 181.1/μL, and median serum IgE was 121.4 IU/ml (IQR, 27.9 - 439.3 IU/ml). FeNO was positively correlated with serum IgE (p=0.003), but not correlated with blood eosinophils (p=0.064). Serum IgE and blood eosinophils were positively correlated with each other (p=0.03). FeNO was not correlated with CT measured markers such as LAV% and √Aaw at Pi10. Conclusions: FeNO can be an easy, noninvasive and useful marker of eosinophilic airway inflammation in stable COPD patients.

Background and objective: COPD is one of the leading causes of morbidity and mortality worldwide, and its prevalence continues to increase. Although spirometry is indispensable for the diagnosis of COPD, other simple and reliable tools are necessary for screening of COPD because spirometry is not widely available. This study investigated the usefulness of a combination of an electronic FEV1/FEV6 meter (PiKo-6) with a COPD questionnaire as a screening method in patients with cardiovascular diseases. Methods: The PiKo-6 and the COPD questionnaire of the International Primary Care Airways Group were used to screen patients attending a cardiovascular outpatient clinic. Patients with FEV1/FEV6

This paper presents the effects of the cross-sectional in-plane crystal orientation (θ) on the structural strength of single crystal turbine vanes using the finite element method (FEM). The material of the turbine vanes is the single crystal superalloy TMS-75. The obtained results show that the elastic constant matrix (c'44) changes were by above 60% due to the orientation variation (0° < θ < 90°). The dependency of the structural strength of the turbine vane on the crystal orientation was calculated using von Mises stress equation. The strength of the turbine vane was strongly related to θ, and also related to the model shape and load. This influence becomes more significant near the leading edge of the turbine vane where it is most likely to fracture.

A 29-year-old woman with primary myelofibrosis developed severe pneumonia, and 20 days later her 31-year-old sister also contracted pneumonia. The first patient had been in contact with parakeets but the second patient had not been in contact with any birds. Psittacosis was diagnosed in both cases by microplate immunofluorescence antibody technique. Person-to-person transmission between the sisters was suspected to have taken place.

A 21-year-old man presented persistent dry cough, general malaise, loss of appetite, decreased sexual desire and double vision. Chest radiograph revealed a mass shadow in the left upper lobe. Histopathological diagnosis of the tumor was squamous cell carcinoma. Brain computed tomography and magnetic resonance imaging revealed a metastasis to the pituitary gland. Hypopituitarism was diagnosed by pituitary function tests. Diabetes insipidus was absent and the function of the posterior lobe of the pituitary gland was preserved. Hypopituitarism due to pituitary metastasis is a rare complication of lung cancer, and has never been reported in a patient as young as 21 years old.

Study objective To compare the etiology of community-acquired pneumonia in Japan and Western countries, the causative pathogens were prospectively investigated in patients requiring hospitalization. Design Prospective study over a 3-year period. Setting A community general hospital in Japan. Patients Three hundred twenty-six episodes of community-acquired pneumonia in 318 patients admitted to the hospital between July 1994 and June 1997. Methods The microbiological diagnosis was based on the results of quantitative sputum culture, blood culture, and other invasive procedures, including transthoracic needle aspiration or bronchoscopic examination. Serologic tests for Mycoplasma pneumoniae , Chlamydia spp, Legionella spp, and viruses were also routinely performed. Results Causative pathogens were identified in 199 episodes (61%). Streptococcus pneumoniae was the most common pathogen (23%), followed by Haemophilus influenzae (7.4%), M pneumoniae (4.9%), and Klebsiella pneumoniae (4.3%). The Streptococcus milleri group and Chlamydia pneumoniae were detected in 3.7 and 3.4% of the episodes, respectively. Pneumonia due to Legionella spp was recognized in only two patients. Conclusions The etiology of community-acquired pneumonia in Japan did not differ markedly when compared with that of Western countries except for the low incidence of Legionella pneumonia. C pneumoniae and the S milleri group, which are emerging or newly recognized pathogens, were also significant causative microorganisms.

Mesoscopic structures of SiC fibers produced from polycarbosilane by different methods were studied by diffraction and small-angle scattering of neutrons and x-rays. Microvoids of a size of 4–10 Å in diameter have been observed for the first time by neutron scattering in a medium momentum transfer range (Q = 0.1–1.0 Å−1). The size and the volume fraction of β–SiC particles were determined for fibers prepared at different heat-treatment temperatures. The results show that wide-angle neutron scattering measurements are especially useful for the study of the mesoscopic structure of multicomponent materials.

We report a case of a 60-year-old woman who developed a tracheal fistula 20 months after mediastinal radiation while being treated with bevacizumab. She presented with a large right-sided mediastinal mass given a diagnosis of stage IIIB adenocarcinoma. She was treated with definitive thoracic radiation (figure 1) and a concurrent chemotherapy, including both cisplatin and docetaxel. Eleven months after chemoradiotherapy …

Background In patients with pulmonary tuberculosis (TB), shortening the time to sputum culture conversion is desirable to reduce the likelihood of mycobacterial transmission. A persistent positive sputum culture after 2 months of treatment is reported to be associated with the presence of cavitation and the extent of disease on chest X-ray, high colony count, diabetes mellitus, and smoking. However, little is known about factors affecting the time to sputum culture conversion. This study was conducted to evaluate factors affecting the time to sputum culture conversion throughout the course of treatment in adults with pulmonary TB. Methods This study was performed using a database of the medical records of patients with active pulmonary TB who were treated at Hirakata Kohsai Hospital in Hirakata City, Osaka, Japan, from October 2000 to October 2002. Cox proportional-hazards analysis was used to evaluate factors affecting the time to sputum culture conversion after adjusting for potential confounders. Results The data of 86 patients with pulmonary TB were analyzed. The median time to sputum culture conversion was 39 days, and the maximum time was 116 days. The Cox proportional-hazards analysis showed that a higher smear grading (HR, 0.40; 95%CI, 0.23–0.71) and a history of ever smoking (HR, 0.48; 95%CI, 0.25–0.94) were associated with delayed sputum culture conversion. Conclusion High smear grading and smoking prolonged the time to sputum culture conversion in adults with pulmonary TB. To effectively control TB, measures to decrease the cigarette smoking rate should be implemented, in addition to early detection and timely anti-TB treatment.

A case of pulmonary Mycobacterium avium (M. avium) disease associated with idiopathic CD4+ T lymphocytopenia is reported. A rapidly growing pulmonary nodule was detected on a chest roentgenogram in a young man. Bronchoscopic examination revealed M. avium infection. Hematological studies showed a low CD4+ cell count in the absence of any identifiable immunodeficiency, including human immunodeficiency virus (HIV) infection. With the combination of chemotherapy and surgery, he had a good clinical outcome. Idiopathic CD4+ T lymphocytopenia should be considered in patients with unexplained opportunistic infection.

We report 2 cases of Legionella pneumonia in individuals who were exposed to aerosols during maintenance of a cooling tower at a waste processing plant. This report documents the first known occupation-related outbreak of Legionella pneumonia in Japan.

A new time-of-flight neutron powder diffractometer, VEGA, with three banks of one-dimensional position-sensitive detectors has been constructed and is now being commissioned at KENS. The design and performance are briefly described together with some initial experimental results.

A 33-y-old man with Hyper-IgM syndrome developed a severe tuberculous disease complicated by pleuritis and spondylitis. An abnormally decreased CD4/CD8 ratio, decreased CD4 + T-cell count and depressed natural killer cell activity implicated a coexistent cell-mediated immunodeficiency. To our knowledge, this is the first detailed report of tuberculosis associated with Hyper-IgM syndrome.

A 63-year-old male with liver cirrhosis due to type-C hepatitis virus was admitted on June 14, 1999 to our hospital with complaints of dyspnea, and blisters, swelling and purpuras on his legs. He had consumed raw fish one or two days before. He was already in a state of shock with sepsis and disseminated intravascular coagulation shortly after the admission. Although treatment with MEPM and MINO for sepsis, and daltepalin sodium, antithrombin III and gabexate mesilate for disseminated intravascular coagulation was begun within 12 hours, he died only 30 hours after admission. The causative organism was detected from the blood and the contents of blisters, and was determined as Vibrio vulnificus. On autopsy, Vibrio vulnificus was also detected from skin and muscular tissue of his legs, but necrotizing fasciitis were not apparently revealed. Coagulating necrosis and acute tubular necrosis were verified in intestine and kidneys respectively probably due to ischemic changes. Pseudolobuli were formed and a small hepatocellular carcinoma was detected in the liver. Vibrio vulnificus has two infection channels; one is oral intake and the other is an external wound. The former is said to become serious. It has a rather short period from the starting of the symptom to death, and is highly fatal. If this bacteria is suspected by the clinical coarse of the patients or the laboratory examinations, it is necessary to dose effective antibiotics in its early stage. And for prevention, susceptible patients must be informed of the existence of this disease and the necessity of adequately heating raw seafood.

Objective To evaluate the indications, efficacy, and safety of transthoracic needle aspiration (TNA) in diagnosing community-acquired pneumonia (CAP). Methods TNA procedure was performed using an ultrathin needle with ultrasonography and/or computed tomography. The aspirate samples were Gram-stained and sent for cultures. The results were compared with those from conventional microbiological studies. Patients Sixty patients with CAP who were admitted to the hospital and were studied prospectively between July 1994 and June 1999 were included in the study. Results TNA culture was positive in 30 cases (50.0%). Streptococcus pneumoniae was the most frequently isolated pathogen, followed by the Streptococcus milleri group, and anaerobes. The results of TNA were consistent with those of quantitative sputum cultures in 9 patients and with those of blood cultures in 4. Complications arose in 3 patients who developed small to moderate pneumothorax. Conclusions TNA is a safe procedure with a good diagnostic yield. In particular, anaerobes or microaerophils such as the S. milleri group were highly detectable by TNA. The results obtained by TNA were highly consistent with those obtained by the gold standard methods. Combined with conventional methods, TNA is considered highly useful for determining the etiology of CAP.(Internal Medicine 40: 873-877, 2001)

No report has been found comparing Chlamydia pneumoniae (C. pneumoniae) pneumonia radiographically with other atypical pneumonias, Chlamydia psittaci (C. psittaci) pneumonia and Mycoplasma pneumoniae (M. pneumoniae) pneumonia. We described the chest radiographs of three kinds of pneumonia cases: 46 cases of C. pneumoniae pneumonia, 39 cases of C. psittaci pneumonia, and 131 cases of M. pneumoniae pneumonia. Radiographic shadows were categorized into main shadows and sub-shadows. The main shadows are classified from the viewpoint of the characteristics; air space consolidation(AS), ground-glass opacity(GG), reticular shadow(RS), bronchopneumonia(BP), and small nodular shadows (SN). The size, the site, and the number of the main shadows were also analyzed. In comparison among the three pneumonias, BP was the most frequent in M. pneumoniae pneumonia (0.40/case). AS predominated in C. pneumoniae pneumonia (0.67/case), and GG in C. psittaci pneumonia (0.62/case). The number of main shadows was equal, about 1.4/case in three pneumonias. Large shadows were less frequent in M. pneumoniae pneumonia than C. pneumoniae pneumonia (p = 0.02) and C. psittaci pneumonia (p = 0.01). Main shadows were more frequent in the outer zone in M. pneumoniae pneumonia than C. psittaci pneumonia (p = 0.01), and in the middle zone in C. psittaci pneumonia than in M. pneumoniae pneumonia (p = 0.02). Cases with bilateral main shadows were less common in M. pneumoniae pneumonia (9%) than C. pneumoniae pneumonia(33%, p = 0.001) and C. psittaci pneumonia(30%, p = 0.005). Thickening of bronchovascular bundles as a sub-shadow was most frequently noted in M. pneumoniae pneumonia. Some differences among the three atypical pneumonias were seen in the chest radiograph. However, no specific findings of C. pneumoniae pneumonia were shown radiographically in this study.

We report two cases of severe measles pneumonia. Patient 1, a 17-year-old boy who contracted measles in the acute phase of infectious mononucleosis caused by Epstein-Barr virus (EBV), transmitted the disease to patient 2, his father. Both patients presented severe pneumonia with bilateral diffuse micronodular shadows. Diagnoses were established in both patients by antibody titers for measles and reverse transcriptase-polymerase chain reaction (RT-PCR) of blood and throat swab. Multinucleated giant cells with intranuclear inclusion bodies were revealed in the transbronchial lung biopsy (TBLB) specimen of patient 2. Both patients recovered with pulse steroid therapy.

Vibrio vulnificus (V. vulnificus) infection has recently been drawing attention as a high mortality disease especially in a patient with the preexisting chronic liver disease. The illness caused by V. vulnificus is divided into three groups such as primary septicemia, wound infection and gastrointestinal illness. Primary septicemia, which is the most common in Japan, is defined as a systemic illness presenting fever or hypotension with recovery of V. vulnificus from blood or tissue without the apparent primary focus of infection. We diagnosed four cases as infectious diseases of V. vulnificus by isolating it from each clinical material in Kurashiki Central Hospital from 1984 through 1997. We investigated clinical manifestations of the four cases including season of the onset, presence of drinking habit, underlying diseases, consumption of raw seafood, symptoms, presence of disseminated intravascular coagulation (DIC) or shock, laboratory data, administered antibiotics and the outcomes of the treatment. And for each strain, we also performed in vitro drug susceptibility tests. The age of the patients ranged from 49 to 61 years old (mean 56), and all of the patients were male. Each of them had a chronic liver disease as an underlying disease. Two of them had a history of raw seafood consumption prior to the onset of the illness. Skin manifestations appeared in two of the four patients. All the patients complicated septic shock and DIC. V. vulnificus was isolated from the venous blood cultures of them. Three of the four were given a diagnosis of primary septicemia and one was made a diagnosis of acute cholecystitis which has never been reported previously. Three of the four patients died and only the rest was alive as a result of antimicrobial therapy. In the sensitivity tests, the four strains were revealed to be very sensitive to the antimicrobials such as minocycline, cephalosporins of the third generation and carbapenems. Once patients with a chronic liver disease are infected with V. vulnificus, their prognosis is poor. Every effort should be made to advise not to have uncooked seafood. Physicians should be informed about the characteristics of the disease caused by this bacteria and treat any suspicious case promptly and appropriately.

The authors present a rare case where acute respiratory failure occurred after the intravitreal bevacizumab injection for a branch retinal vein occlusion. Chest CT scan showed ground-glass opacity in the bilateral lung fields. The finding of bronchoalveolar lavage fluid revealed alveolar haemorrhage. Corticosteroid therapy resulted in a rapid improvement of respiratory failure. This report suggests that intravitreal injection of bevacizumab may be associated with diffuse alveolar haemorrhage and acute lung injury.

Asthma and chronic obstructive pulmonary disease (COPD) are among the most prevalent lung diseases. In both asthma and COPD, airway inflammation leads to airway remodeling. Parenchyma of the lung is also influenced by disease conditions. Airway wall thickening/lumen narrowing and parenchymal destruction occur in COPD. In asthma, airway remodeling contributes to the lung parenchyma. Computed tomography (CT) has been widely used as an imaging tool for lung diseases. With the technical advancement of CT, together with the development of analysis software, it is now possible to analyze the lung parenchymal change and airway remodeling quantitatively using CT. This article reviews the role of CT in assessing the lung structure and functions of patients with asthma and COPD.