Atypical presentations of supraventricular arrhythmias constitute a diagnostic challenge which are not frequently reported in literature. Swallowing-induced supraventricular arrhythmia (SI-SVA), ...which was first described in 1926, is an intriguing presentation of supraventricular tachycardia and occurs during a wet or solid swallow. A 67-year-old man presented to our outpatient clinic complaining from recurrent episodes of sensation of palpitations and short duration pressure on his chest while swallowing since the last 2 weeks. Ambulatory rhythm Holter monitoring was suggestive of atrial fibrillation (AF) or atrial tachycardia attacks during swallowing. In addition, electrocardiography performed during solid food swallowing, showed short duration of AF consistent with the patient's symptoms. The patient was successfully treated with amiodarone. The main cause of SI-SVA is not known. Cross-talk of nerves during the impulse propagation might be the underlying cause of this phenomenon.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The aim of the present study was to determine the prevalence of and risk factors for venous thromboembolism (VTE) in exacerbations of chronic obstructive pulmonary disease (COPD). COPD patients ...hospitalised with an exacerbation were included consecutively. Symptoms, signs and clinical, haematological and epidemiological parameters on admission were noted. All patients underwent computed tomographic angiography and ultrasonographic examination for deep vein thrombosis and pulmonary embolism (PE). Wells and Geneva scores were calculated. Patients were followed-up for 1 yr in order to determine mortality. Deep vein thrombosis and PE were detected in 14 and 18 patients, respectively. The prevalence of VTE was three times higher in patients with an exacerbation of unknown origin than in patients with an exacerbation of known origin (p = 0.016). Of patients with VTE, 20 (95%) had high D-dimer levels. The negative predictive value of D-dimer testing was 0.98. Although the moderate- and high-risk categories of both the Wells and Geneva methods covered all PE patients, the Wells method identified 49% less potential patients for PE investigation. Mortality at 1 yr was higher (61.9% versus 31.8%) in VTE patients (p = 0.013). VTE is a common problem in COPD patients hospitalised with an exacerbation, leading to high long-term mortality. D-dimer levels and the Wells criteria can be used to determine whether or not these patients are assessed for a thromboembolic event.
Benzimidazolium salts and their Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation (PEPPSI) palladium N-heterocyclic carbene (Pd-NHC) based complexes have been synthesized and ...their structures characterized with a number of different instrumental techniques including NMR (1H and 13C), IR, EI-MS (for 2), X-ray (for 1, 2 and 4) and elemental analysis. The cytotoxicity of all the compounds was tested using the human embryonic kidney (HEK-293T), human breast epithelial adenocarcinoma (MDA-MB-231), and human colon epithelial colorectal adenocarcinoma (DLD-1) cell lines. The benzimidazolium salts (2–5) had more cytotoxic activity against cancerous cells compared with the metal complexes (6–9), which curiously exhibited no activity against any of the cell lines. Based on the IC50 values, compound 5 displayed the highest in vitro anticancer activity among compounds 2–9.
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•Benzimidazolium salts and Pd-NHC complexes were prepared and characterized with a number of instrumental techniques.•The cytotoxicity of compounds was tested against various cell lines.•While compounds 2–5 exhibited cytotoxicity against tested cell lines, metal complexes 6–9 had no cytotoxic activity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Meningiomas are very commonly diagnosed intracranial primary neoplasms, of which the chordoid subtype is seldom encountered. Our aim was to retrospectively review preoperative MR imaging of ...intracranial chordoid meningiomas, a rare WHO grade II variant, in an effort to determine if there exist distinguishing MR imaging characteristics that can aid in differentiating this atypical variety from other meningioma subtypes.
Ten cases of WHO grade II chordoid meningioma were diagnosed at our institution over an 11-year span, 8 of which had preoperative MR imaging available for review and were included in our analysis. Chordoid meningioma MR imaging characteristics, including ADC values and normalized ADC ratios, were compared with those of 80 consecutive cases of WHO grade I meningioma, 21 consecutive cases of nonchordoid WHO grade II meningioma, and 1 case of WHO grade III meningioma.
Preoperative MR imaging revealed no significant differences in size, location, signal characteristics, or contrast enhancement between chordoid meningiomas and other meningiomas. There were, however, clear differences in the ADC values and normalized ADC ratios, with a mean absolute ADC value of 1.62 ± 0.33 × 10(-3) mm(2)/s and a mean normalized ADC ratio of 2.22 ± 0.47 × 10(-3) mm(2)/s in chordoid meningiomas compared with mean ADC and normalized ADC values, respectively, of 0.88 ± 0.13 × 10(-3) mm(2)/s and 1.17 ± 0.16 × 10(-3) mm(2)/s in benign WHO grade I meningiomas, 0.84 ± 0.11 × 10(-3) mm(2)/s and 1.11 ± 0.15 × 10(-3) mm(2)/s in nonchordoid WHO grade II meningiomas, and 0.57 × 10(-3) mm(2)/s and 0.75 × 10(-3) mm(2)/s in the 1 WHO grade III meningioma.
Chordoid meningiomas have statistically significant elevations of ADC and normalized ADC values when compared with all other WHO grade I, II, and III subtypes, which enables reliable preoperative prediction of this atypical histopathologic diagnosis.
Although the large majority of sellar tumours are pituitary adenomas, several other pituitary and non-pituitary origin tumours arise in the sellar and parasellar regions. Given their location, ...non-adenomatous lesions frequently mimic pituitary macroadenomas and can pose a diagnostic challenge for the radiologist. Distinguishing rare sellar lesions from the common macroadenoma helps to direct the correct surgical approach and reduce the risk of incomplete resection and/or complications such as cerebrospinal fluid leak with the potential for meningitis. The purpose of this article is to review the imaging features of non-pituitary-origin sellar tumours, focusing on characteristics that may distinguish them from pituitary macroadenomas. Lesions include meningioma, metastatic disease, epidermoid cyst, germinoma, chondrosarcoma, giant cell tumour, and giant aneurysm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Thyroid incidentaloma is a common disorder in endocrinology practice. Current literature regarding the risk of thyroid cancer in incidentalomas found in patients with non-thyroid cancer is limited.
...The aim of the present study was to investigate the frequency of thyroid malignancy in thyroid incidentalomas detected in patients with non-thyroid cancer.
Case control study.
The database of 287 thyroid nodules from 161 patients with a history of non-thyroid cancer followed between 2008 and 2014 were retrospectively evaluated.
From 287 thyroid nodules, 69.7 % had a benign final cytology. Thyroid cancer detected in one nodule while follicular neoplasia detected in 4 nodules, atypia of unknown significance (AUS) detected in 10 nodules, Hurthle cell neoplasia detected in 5 nodules and suspicious for malignancy detected in 6 nodules according to fine needle aspiration biopsy results. Metastasis of the non-thyroid cancer to the thyroid gland was detected in 4 nodules. Twenty seven nodules from 15 patients were removed with surgery. There were 3 malignant nodules found after surgery (1 papillary, 1 follicular and 1 medullary cancer). In addition to these three thyroid cancers, two patients with benign nodules had co-incidental thyroid cancer detected after surgery. Finally, 11.1 % of thyroid nodules which underwent thyroid surgery had malignant histopathology except for co-incidental and metastatic cancers.
The frequency of thyroid malignancy seems not to be substantially increased in incidental thyroid nodules detected in patients with non-thyroid cancer when these patients were evaluated in nodule-based approach.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Computational capabilities of the largest high performance computing systems have increased by more than 100 folds in the last 10 years and keep increasing substantially every year. This increase is ...made possible mostly by multi-core technology besides the increase in clock speed of CPUs. Nowadays, there are systems with more than 100 thousand cores installed and available for processing simultaneously. Computational simulation tools are always in need of more than available computational sources. This is the case for especially complex, large scale flow problems. For these large scale problems, the soft error tolerance of the simulation codes should also be encountered where it is not an issue in relatively small scale problems due to the low occurrence probabilities. In this study, we analyzed the reaction of an incompressible flow solver to randomly generated soft errors at several levels of computation. Soft errors are induced into the final global assembly matrix of the solver by manipulating predetermined bit-flip operations. Behaviour of the computational fluid dynamics (CFD) solver is observed after iterative matrix solver, flow convergence and CFD iterations. Results show that the iterative solvers of CFD matrices are highly sensitive to customized soft errors while the final solutions seem more intact to bit-flip operations. But, the solutions might still differ from the real physical results depending on the bit-flip location and iteration number. So, the next generation computing platforms and codes should be designed to be able to detect bit-flip operations and be designed bit-flip resistant.
Graphic abstract
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CEKLJ, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The aim of the present study is to evaluate a gamma probe with active shielding by using GEANT4 simulation framework. We used BGO scintillators both for gamma detection and active shielding from a ...point radioactive source, namely 140 keV gammas from
99
m
Tc
. All scintillators were coupled to the silicon photomultipliers with an active area of
3
×
3
mm
2
. The response of the gamma probe to radiation was simulated using the optical photon transportation available in the GEANT4 package. We used the simulation results to determine the sensitivity, spatial and angular resolution, and shielding efficiencies in the air and scattering medium for the proposed gamma probe model according to NEMA NU 3-2004 standards. The ability of the probe to find the direction of emission was also evaluated. The sensitivity of the probe was found between 1262 - 42284 cps/MBq in the scattering medium based on two scenarios based on active shielding use. In terms of FWHM, the spatial resolution in scattering medium at 30 mm source-to-probe distance was 31 mm and the angular resolution at the same distance was
59
∘
. The shielding effectiveness of the probe was in the range of 89.90 ±
0.65
%
and 97.20 ±
0.19
%
. The emission directions of gammas were found with an error of less than 8°.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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