Evaluation of atherosclerosis as a risk factor in COPD patients by measuring the carotid intima-media thickness.

BACKGROUND: This study aimed to evaluate atherosclerosis as comorbidity by measuring the carotid (bulb and common carotid artery) Carotid intima-media thickness in COPD-diagnosed patients and to evaluate the relationship of atherosclerosis with the prevalence of COPD, hypoxemia and hypercapnia. METHODS: This study was conducted out between January 2019-December 2019 consisting of a total of 140 participants (70 COPD-diagnosed patients-70 healthy individuals). The COPD-diagnosed patients have been planned according to the selection and diagnosis criteria as per the GOLD 2019 guide. It is planned to evaluate as per prospective matching case-control study of the carotid thickness, radial gas analysis, spirometric and demographic characteristics of COPD diagnosed patients and healthy individuals. RESULTS: The average Carotid intima-media thickness in COPD patients was 0.8746±0.161 (p<0.05), and the thickness of the carotid bulb was 1.04±0.150 (p<0.05). In the control group, the average CCA intima-media thickness was 0.6650±0.139 (p<0.05), and the thickness of the carotid bulb was 0.8250±0.15(p<0.05) For the carotid thickness that has increased in COPD diagnosed patients a significant relationship is determined between hypoxemia (p<0.05) and hypercapnia(p<0.05). A significant relationship determined between CIMT and severity of COPD (p<0.05) The CIMT was high in COPD patients with hypoxemia and hypercapnia(p<0.05). CONCLUSION: Significant difference was determined between the severity (grades) of COPD (mild, moderate, severe, very severe) in carotid thickness. Also, CIMT was found to be high in patients who is in the early phases of the prevalence of COPD. In COPD-diagnosed patients, it was determined that severity of COPD, hypoxemia, hypercapnia and age were determining factors of atherosclerosis.

The efficacy of 18F-FDG PET/CT in monitoring disease progression in malignant pleural mesothelioma.

OBJECTIVE: In the event of suspicion of malignant pleural mesothelioma (MPM) progression, imaging plays an important role. We aimed to evaluate the efficacy of 18F-FDG PET/CT in monitoring disease progression by comparing it with CT, and estimate median overall survival (OS) according to progression status with CT and 18F-FDG PET/CT. MATERIALS AND METHODS: This was an observational, retrospective, single-institution study with MPM patients who had both 18F-FDG PET/CT and CT for monitoring disease progression from March 2009 to February 2020. Clinical features, radiological findings, and progression status according to CT [radiologic progression negative (RPN), radiologic progression positive (RPP)] and 18F-FDG PET/CT [metabolic progression negative (MPN), metabolic progression positive (MPP)] were recorded. The discrepancies and concordance between two methods were evaluated. The OS was estimated using the Kaplan-Meier method. RESULTS: A total of 56 patients were included. There were thirty-one (55.3%) RPN and 25 (44.7%) RPP, while there were 26 (46.5%) MPN and 30 (53.5%) MPP. All RPP patients were also found to be MPP, however, among RPN, 5 patients (8.9% of all patients) were evaluated as MPP. The concordance between two methods in monitoring disease progression was very good (K = 0.423; p < 0.01). The OS was 26 ±â€¯2.6 months in all patients. Kaplan-Meier curves between RPN and RPP, and between MPN and MPP did not show statistically significant differences (p = 0.56 and p = 0.25, respectively). CONCLUSIONS: Both methods are equally acceptable in monitoring disease progression in MPM, even though 18F-FDG PET/CT detected more progression than CT did.

The Differentiation of Metastatic Mediastinal Lymph Nodes From Benign Hypermetabolic Lesions.

Background Anthracosis may cause a positron emission tomography/computed tomography (PET/CT) false positivity in mediastinal and hilar lymph nodes. We aimed to evaluate the radiological features and the maximum standardized uptake values (SUVmax) of the mediastinal lymph nodes with anthracosis or squamous cell lung cancer metastasized. Methodology Patients diagnosed with anthracosis or squamous cell lung cancer with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) between January 1, 2015, and November 15, 2020, in a tertiary hospital were enrolled. The squamous cell subtype of lung cancer was selected due to its association with tobacco use, biomass, and air pollution. Anthracosis may occur due to the same etiologic reasons. Results A total of 190 patients met the study enrollment criteria, of which 86 were diagnosed with anthracosis and 33 with squamous cell lung cancer lymph metastasis. Median values for short axis, long axis, SUVmax, shape features, and presence of calcification were found significantly different between the groups. In receiver operating characteristic (ROC) analysis, the SUVmax cut-off value was calculated as 6.61. With this cutoff value, the negative predictive value (NPV) was 92.5% and the positive predictive value (PPV) was 54% for differentiating anthracosis and malignant lymph nodes metastasis. Conclusions We conclude that the evaluation of the shape and metabolic activities of the anthracotic lymph nodes detected by PET/CT together with EBUS-TBNA granted a more accurate staging of the patients and more cancer patients will benefit from surgical treatment.

A novel method for hemodynamic analysis of penile erection.

Measurement of blood flow velocity through the cavernosal arteries via penile color Doppler ultrasound (PDUS) is the most common objective method for the assessment of erectile function. However, in some clinical cases, this method needs to be augmented via the invasive intracavernosal pressure (ICP) measurement, which is arguably a more direct index for erectile function. The aim of this study is to develop a lumped parameter model (LPM) of the penile circulation mechanism integrated to a pulsatile, patient-specific, bi-ventricular circulation system to estimate ICP values non-invasively. PDUS data obtained from four random patients with erectile dysfunction are used to develop patient-specific LPMs. Cardiac output is estimated from the body surface area. Systemic pressure is obtained by a sphygmomanometer. Through the appropriate parameter set determined by optimization, patient-specific ICP values are predicted with only using PDUS data and validated by pre- and post-papaverine injection cavernosometry measurements. The developed model predicts the ICP with an average error value of 3 mmHg for both phases. Penile size change during erection is predicted with a ~15% error, according to the clinical size measurements. The developed mathematical model has the potential to be used as an effective non-invasive tool in erectile function evaluation, expanding the existing clinical decision parameters significantly.

Monte Carlo method solution of the broadband fluorescent radiative transfer equation considering fluorescent cascade.

Altering wavelength via fluorescent particles is used in various applications. The solution of the broadband radiative transfer equation (RTE) for absorbing and anisotropically scattering a fluorescent medium is presented in this study considering fluorescent cascade, along with a Monte-Carlo-method-based solution of the equation. The path-length-based Monte Carlo method, the dual-stage method, and its modified version, the multi-stage method, which are used for solving the RTE in a fluorescent medium for biomedical and lighting applications, are not capable of accurately solving the broadband RTE with fluorescent cascade. Therefore, a collision-based Monte Carlo method is applied to overcome the limitations of these approaches. An accuracy comparison with the alternative methods is presented along with the flow chart and codes of the proposed method.

Imaging Features of Thoracic Manifestations of Behçet's Disease: Beyond Pulmonary Artery Involvement.

BACKGROUND: Behçet's disease is a chronic multisystemic vasculitis affecting vessels of different sizes in various organs. Thoracic manifestations of the disease show a wide spectrum involving a variety of anatomic structures within the chest. However, pulmonary artery involvement is a typical manifestation of the disease that contributes significantly to mortality in patients. The study aimed to analyze CT features of thoracic manifestations, particularly pulmonary artery involvement, and to quantitatively assess bronchial arteries in Behçet's disease. METHODS: Patients with Behçet's disease who underwent CT scans for suspected thoracic involvement between 2010 and 2018 were included. CT findings of 52 patients were retrospectively analyzed for thoracic manifestations of the disease. Bronchial arteries were assessed regarding diameter in patients with/without pulmonary artery involvement. The pulmonary symptoms were noted. RESULTS: Of the 52 patients, 67% had thoracic manifestations including pulmonary artery involvement, parenchymal changes, superior vena cava thrombosis, and intracardiac thrombus. Pulmonary artery involvement was observed in 50% of the cohort. Peripheral pulmonary arteries (77%) were the most commonly affected branches, followed by lobar (42%) and central (35%) pulmonary arteries. Other thoracic findings were significantly correlated with pulmonary artery involvement (p<0.05). Compared to patients without pulmonary artery involvement, those with pulmonary artery involvement had a higher bronchial artery diameter (p<0.05) and occurrence rate of dilated bronchial arteries. CONCLUSION: Involvement of peripheral pulmonary arteries is frequently encountered in Behçet's disease and it can resemble pulmonary nodules. Dilated bronchial arteries, which can be observed in cases of pulmonary artery involvement, should be considered in patients with hemoptysis.

Unusual cause of filling defect in pulmonary artery: pulmonary artery sarcoma.

Pulmonary artery (PA) sarcoma is an extremely rare malignant tumor of pulmonary artery. It is often misdiagnosed as pulmonary thromboembolism (PTE) because of its clinical and imaging features which are quite similar to PTE. Multimodality diagnostic imaging and recognition of specific imaging characteristics with appropriate clinical suspicion are required to make correct diagnosis. In this report, we present a case of PA sarcoma with imaging and clinical features as well as emphasize significance of using multimodality imaging.

Video-Assisted Thoracoscopic Treatment of Coelomic Cysts.

Background: Coelomic cysts are uncommon benign cyctic lesions of the mediastinum. Complete resection of the cyst with surgical treatment is indicated depending on whether the patient is symptomatic or whether the cyst grows during follow-up, or whether the diagnosis is uncertain. Surgical treatment prevents complications, relieves symptoms, and establishes diagnosis. Video-assisted thoracoscopic surgery (VATS) is the best method for excision of these cysts. This approach is safe and effective, has low morbidity, and shortens the length of hospital stay Objectives: We aimed to analyze our experience with coelomic cysts through VATS, reviewing clinical, radiological, and pathological features, early and long-term results of surgical management. Patients and Methods: Between January 2011 and December 2018, 20 patients with coelomic cysts who underwent VATS at our clinic were included in the study. Results: The study included 11 female and 9 male patients with a mean age of 45.6 years. Symptoms were present in 17 patients and 3 were asymptomatic. The average cyst diameter was 5.4 cm (range 2-8 cm). Fourteen of them were right sided, the others were left sided. There were no operative mortality and complications. Postoperatively there were no complications, in all cases course was uneventful, all of them were discharged after a mean of 3 days (range 2-6 days). Conclusions: Considering the low complication rate and hospital stay, excision of coelomic cysts through VATS is extremely safe and comfortable, so it should be considered the primary therapeutic procedure.

Prognostic significance of preoperative consolidation to maximum tumour diameter ratio and SUVmax in pathological stage I lung adenocarcinoma.

OBJECTIVES: Consolidation/tumour (C/T) ratio means the maximum diameter of the consolidation is divided by the maximum diameter of the tumour and it is predictive for pathologic subtypes and prognosis after resection of the tumour. The purpose of this study is to clarify impact of C/T ratio along with maximum standardized uptake value (SUV) in pathological stage I lung adenocarcinoma. METHODS: Only patients with pathological stage I lung adenocarcinoma diagnosed by resection were included. Prognostic impact of C/T ratio and SUVmax were analysed by using regression analyses. RESULTS: Totally 156 patients (121 males, 35 females) were evaluated retrospectively. Overall survival (OS) and progression free survival (PFS) were higher in patients with C/T ratio ≥0.5 (OS: 46.3 ± 23.7 vs 30.4 ± 14.6, P = 0.002 and PFS: 43.0 ± 25.4 vs 27.8 ± 15.8, P = 0.005). But PFS and OS curves did not reveal any significant differences with Kaplan-Meier method (P = 0.45 and P = 0.055 respectively). Resection type (limited vs anatomic) and C/T ratio were predictors for OS in multivariate analyses (resection type: HR: 2.21 (1.01-4.83), P = 0.045 and C/T ratio: HR: 0.44 (0.20-0.98), P = 0.045). For PFS, resection type and SUVmax had prognostic significance (resection type: HR: 3.56 (1.64-7.74), P = 0.001 and SUVmax: HR: 1.31 (0.82-2.99), P = .002). CONCLUSION: In pathological stage 1 lung adenocarcinomas, SUVmax and surgery type are important predictors for recurrence rates. For early stage, adenocarcinoma patients with high SUVmax value, tumour size ≥3 cm and high grade subtype, C/T ratio should not be considered significant alone on survival and recurrence.

A novel approach to describe chemical environments in high-dimensional neural network potentials.

A central concern of molecular dynamics simulations is the potential energy surfaces that govern atomic interactions. These hypersurfaces define the potential energy of the system and have generally been calculated using either predefined analytical formulas (classical) or quantum mechanical simulations (ab initio). The former can accurately reproduce only a selection of material properties, whereas the latter is restricted to short simulation times and small systems. Machine learning potentials have recently emerged as a third approach to model atomic interactions, and are purported to offer the accuracy of ab initio simulations with the speed of classical potentials. However, the performance of machine learning potentials depends crucially on the description of a local atomic environment. A set of invariant, orthogonal, and differentiable descriptors for an atomic environment is proposed, implemented in a neural network potential for solid-state silicon, and tested in molecular dynamics simulations. Neural networks using the proposed descriptors are found to outperform ones using the Behler-Parinello and smooth overlap of atomic position descriptors in the literature.

Could SUVmax be an auxiliary parameter in the clinical management of pulmonary hydatid disease?

OBJECTIVE: The aim of this study was to investigate the role of 18F-fluorodeoxyglucose positron emission tomography/computerized tomography (FDG-PET/CT) in the diagnosis and treatment of pulmonary hydatid disease and also compare the morphological characteristics of the lesions with SUVmax values and identify complicated disease. METHODS: Thirty-six patients with a diagnosis of pulmonary hydatid disease who underwent 18F-FDG PET/CT imaging were included in this retrospective study. The size of the lesions, morphological characteristics, accompanying parenchymal and pleural findings, SUVmax and HUmean values and FDG uptake in mediastinal lymph nodes were noted. The relationship between morphologic properties, SUVmax of the lesions and lymphatic FDG uptake was analysed. RESULTS: A total of 99 lesions of 36 patients were classified as solid (7.1%), cystic (53.5%), semisolid (20.2%) and cavitary (19.2%). Thirty-two of the lesions were encapsulated, 38 of the lesions had border irregularity. Accompanying consolidation was present in 10 cases, bronchial obstruction in 9, pleural thickening in 28 and effusion in 3. There was positive correlation between lesions HUmean and SUVmax values (r = 0.285). SUVmax values were significantly higher in lesions with irregular borders, solid or semisolid type and presence of consolidation, bronchial obstruction and pleural thickening. Also more lymphatic FDG uptake was detected in this group. CONCLUSION: Higher SUVmax values may be a useful parameter in the diagnosis of complicated pulmonary hydatid disease. FDG-PET may provide guidance for determining the priority of lesion for surgery in cases with multiple lesions and may be helpful to evaluate the response to medical treatment.

Plasmon coupling between complex gold nanostructures and a dielectric substrate.

Intercoupling of an incident electric field in metal nanoparticles causes asymmetric distribution of surface charges, which eventuates in shifting of the surface plasmon resonance frequency. This feature can be used in tuning the surface plasmon resonance and controlling the light absorption in a desired wavelength. This work provides a theoretical study of the plasmonic properties of complex gold nanostructures on a dielectric substrate where the nanoparticles have different morphologies. For analysis, we have developed a discrete dipole approximation with surface interactions-z, which is the third version of the MATLAB-based DDA-SI toolbox. In this version, lower-upper decomposition of the interaction matrix is used as a preconditioning of the LSQR iterative solver. This method accelerates the DDA-SI calculations by decreasing the total number of iteration steps and decreases the relative residual to achieve more accurate results. In the analysis, nanostructures are assumed to be gold dimers, trimers, and quadrumers with different sizes and elongations of cubical or spherical geometries on a BK7 substrate. The results show that absorption spectra exhibit both red- and blueshifted plasmon resonances in array, depending on the particle shape and elongation. The cubic structure of gold array provides the highest absorption efficiency, while the spherical structures give wider bandwidth; the combination of these structures could be used to design a system with intended features. We demonstrate that the geometrical symmetry plays an important role in the plasmon resonance of gold arrays, and it is shifted when the symmetry of the array is broken.

Approximate Bayesian computation techniques for optical characterization of nanoparticle clusters.

Characterization of nanoparticle aggregates from observed scattered light leads to a highly complex inverse problem. Even the forward model is so complex that it prohibits the use of classical likelihood-based inference methods. In this study, we compare four so-called likelihood-free methods based on approximate Bayesian computation (ABC) that requires only numeric simulation of the forward model without the need of evaluating a likelihood. In particular, rejection, Markov chain Monte Carlo, population Monte Carlo, and adaptive population Monte Carlo (APMC) are compared in terms of accuracy. In the current model, we assume that the nanoparticle aggregates are mutually well separated and made up of particles of same size. Filippov's particle-cluster algorithm is used to generate aggregates, and discrete dipole approximation is used to estimate scattering behavior. It is found that the APMC algorithm is superior to others in terms of time and acceptance rates, although all algorithms produce similar posterior distributions. Using ABC techniques and utilizing unpolarized light experiments at 266 nm wavelength, characterization of soot aggregates is performed with less than 2 nm deviation in nanoparticle radius and 3-4 deviation in number of nanoparticles forming the monodisperse aggregates. Promising results are also observed for the polydisperse aggregate with log-normal particle size distribution.

Nanolayering around and thermal resistivity of the water-hexagonal boron nitride interface.

The water-hexagonal boron nitride interface was investigated by molecular dynamics simulations. Since the properties of the interface change significantly with the interatomic potential, a new method for calibrating the solid-liquid interatomic potential is proposed based on the experimental energy of the interface. The result is markedly different from that given by Lorentz-Berthelot mixing for the Lennard-Jones parameters commonly used in the literature. Specifically, the extent of nanolayering and interfacial thermal resistivity is measured for several interatomic potentials, and the one calibrated by the proposed method gives the least thermal resistivity.

Surgical treatment of pulmonary arteriovenous malformations.

BACKGROUND/AIM: Pulmonary arteriovenous malformations (PAVMs) are direct communications between the branches of pulmonary arteries and veins. This study evaluates surgically treated cases of pulmonary arteriovenous malformations. MATERIALS AND METHODS: We retrospectively examined 41 cases of PAVM that were operated in our clinic between 1995 and 2012. We obtained the clinical, radiological, and surgical data of the patients from their files. RESULTS: The 41 cases comprised 27 males and 14 females. Their mean age at diagnosis was 39.8 years (range: 9-71). The symptoms were hemoptysis in 28 cases, dyspnea in five, cough in three, and epistaxis in two; three patients were asymptomatic. Twenty-three right and 19 left posterolateral thoracotomies were performed, including one case which was operated bilaterally. Lower lobectomy was performed in 17 patients, lower lobectomy and lingulectomy in two, upper lobectomy in ten, middle lobectomy in two, segmentectomy in seven, and wedge resection in four. Postoperative histopathology was arteriovenous malformation in all cases. CONCLUSION: PAVMs are rare clinical conditions. Surgery remains the first choice when embolization treatment cannot be performed or is not successful, in symptomatic and complicated patients with PAVM, and/or in cases where the PAVM diagnosis cannot be established.

Computed Tomography-Guided Methylene Blue Labeling Prior to Thoracoscopic Resection of Small Deeply Placed Pulmonary Nodules. Do We Really Need Palpation?

Background Video-assisted thoracic surgery (VATS) is widely used for thoracic surgery operations, and day by day it becomes routine for the excision of undetermined pulmonary nodules. However, it is sometimes hard to reach millimetric nodules through a VATS incision. Therefore, some additional techniques were developed to reach such nodules little in size and which are settled on a challenging localization. In the literature, coils, hook wires, methylene blue, lipidol, and barium staining, and also ultrasound guidance were described for this aim. Herein we discuss our experience with CT-guided methylene blue labeling of small, deeply located pulmonary nodules just before VATS excision. Method From April 2013 to October 2016, 11 patients with millimetric pulmonary nodules (average 8, 7 mm) were evaluated in our clinic. For all these patients who had strong predisposing factors for malignancy, an 18F-FDG PET-CT scan was also performed. The patients whose nodules were decided to be excised were consulted the radiology clinic. The favorable patients were taken to CT room 2 hours prior to the operation, and CT-guided methylene blue staining were performed under sterile conditions. Results Mean nodule size of 11 patients was 8.7 mm (6, 2-12). Mean distance from the visceral pleural surface was 12.7 mm (4-29.3). Four of the nodules were located on the left (2 upper lobes, 2 lower lobes), and seven of them were on the right (four lower lobes, two upper lobes, one middle lobe). The maximum standardized uptake values (SUV max) on 18F-FDG PET/CT scan ranged between 0 and 2, 79. Conclusion CT-guided methylene blue staining of millimetric deeply located pulmonary nodules is a safe and feasible technique that helps surgeon find these undetermined nodules by VATS technique without any need of digital palpation.

A new interlayer potential for hexagonal boron nitride.

A new interlayer potential is developed for interlayer interactions of hexagonal boron nitride sheets, and its performance is compared with other potentials in the literature using molecular dynamics simulations. The proposed potential contains Coulombic and Lennard-Jones 6-12 terms, and is calibrated with recent experimental data including the hexagonal boron nitride interlayer distance and elastic constants. The potentials are evaluated by comparing the experimental and simulated values of interlayer distance, density, elastic constants, and thermal conductivity using non-equilibrium molecular dynamics. The proposed potential is found to be in reasonable agreement with experiments, and improves on earlier potentials in several respects. Simulated thermal conductivity values as a function of the number of layers and of temperature suggest that the proposed LJ 6-12 potential has the ability to predict some phonon behaviour during heat transport in the out-of-plane direction.

Thromboembolic Events in Malignant Pleural Mesothelioma.

AIM: Malignant pleural mesothelioma (MPM) increases the risk of thromboembolic events (TEEs). In this retrospective study, we aimed to determine the rate of TEEs in MPM and investigate its relationship with the presence of thrombocytosis, the disease stage, and the tumor histopathology. METHODS: The study included 178 patients who were histopathologically diagnosed as MPM between the years January 2008 and June 2014. RESULTS: The mean age was 58.7 ± 11.8 years, and the median follow-up time was 8 months. Seventy-one patients (39.9%) had thrombocytosis (>350 × 10(3)/mL). In total, 14 (7.9%) TEEs were identified: 6 (3.4%) pulmonary thromboembolism, 6 (3.4%) deep venous thrombosis, and 2 (1.1%) myocardial infarctions. Although 5 (2.8%) of the TEEs preceded the diagnosis of MPM, 1 (0.6%) occurred simultaneously with the diagnosis of MPM and 8 (4.5%) followed the diagnosis of MPM. Thromboembolic event rates were not statistically different based on the presence of thrombocytosis (P = .51), disease stage (P = .14), and histopathology (P = .38). CONCLUSION: The rate of TEEs was 7.9%. Presence of thrombocytosis, disease stage, and histopathology did not affect the incidence of TEEs.

Pulmonary involvement in sea-blue histiocytosis.

Sea-blue histiocytosis is one of the six types of Niemann-Pick disease. It is characterized by childhood onset of hepatosplenomegaly, lack of neurological involvement and diminished sphingomyelinase activity. Pulmonary system is rarely involved sea-blue histiocytosis. In this paper, we present a 39-years-old male who had previously diagnosed as sea-blue histiocytosis at the age of 15. He was admitted to our clinic due to productive cough, hemoptysis, fever and weight loss. His symptoms did not resolve with the antibiotic treatment and further investigations revealed pulmonary involvement of sea-blue histiocytosis. After diagnostic bronchoalveolar lavage, his symptoms were improved, interestingly. This rare entity was discussed with literature survey.

The diagnostic role of capnography in pulmonary embolism.

The aim of this study was to evaluate the diagnostic contribution of alveolar dead space fraction (AVDSf) measured using capnography in patients admitted with suspected pulmonary embolism (PE). A total of 58 patients who were admitted to our hospital with suspected PE between October 2006 and January 2008 were included in this study. All patients were assessed using the Wells clinical score, capnography, computed tomographic pulmonary angiography, D-dimer measurement, lower-extremity venous Doppler ultrasonography, and V/Q scintigraphy. Forty patients (69%) had PE based on computed tomographic pulmonary angiography findings. The AVDSf value with the highest sensitivity and specificity, which was at the same time statistically significant, was 0.09. This value was consistent with the AVDSf value obtained using receiver operating characteristic analysis. In our study, the sensitivity of capnography was 70%, with a specificity of 61.1%, positive predictive value of 80%, and negative predictive value of 47.8%. The use of AVDSf in combination with any of the several scoring systems that evaluate clinical likelihood of PE and D-dimer levels resulted in higher sensitivity and specificity rates for the diagnosis of PE.