14 research outputs found
THE DESIGN OF A DUAL-POLARIZED SMALL BASE STATION ANTENNA WITH HIGH ISOLATION HAVING DIELECTRIC FEEDING STRUCTURE
Abstract-A dual-polarized small base station antenna with a dielectric feeding structure is presented. The proposed antenna is composed of a micro-strip feed line board, eight metallic shorting plates, four dielectric feed substrates, four metallic radiators, a metallic cube, and a radome. A wide impedance bandwidth of 20% (2.45 to 3.0 GHz) is achieved. The proposed antenna has an isolation of greater than 50 dB over the operating bandwidth. Details of the proposed antenna design, and the simulated and measured results are presented and discussed
Fine-Needle Aspiration Cytology of Carcinosarcoma in the Salivary Gland: An Extremely Rare Case Report
Carcinosarcoma of the salivary gland is an extremely rare tumor that is composed of both malignant epithelial and mesenchymal components. Diagnosing carcinosarcoma with fine-needle aspiration cytology is challenging because of its overlapping cytomorphologic characteristics with other high-grade malignant salivary gland tumors. Among the many features, including pleomorphic oncocytoid epithelial components, necrotic background, and mitoses, recognizing the singly scattered atypical spindle cells is most essential in carcinosarcoma. We present a case of a 66-year-old male patient with characteristic features of carcinosarcoma, who was successfully treated by wide local excision and subsequent radiation therapy
Programmed Death-Ligand 1 Expression and Its Correlation with Lymph Node Metastasis in Papillary Thyroid Carcinoma
Background The immunotherapeutic role of programmed death-ligand 1 (PD-L1) in life expectancy in many cancers has been highlighted. However, data regarding PD-L1 expression in papillary thyroid carcinoma (PTC) are limited. In this study, we describe the PD-L1 and programmed cell death protein 1 (PD-1) expressions in PTC and analyze their correlation with lymph node (LN) metastasis. Methods Clinicopathological data were obtained from 116 patients with PTC who were treated in Gyeongsang National University Hospital, Jinju, Korea in 2009. Tissue microarray blocks were made using representative paraffin blocks of classical PTCs excluding follicular variants. Two pathologists graded the proportion and intensity of PD-L1 and PD-1 expression in both tumor and inflammatory cells. According to their proportions, positive PTC cells were scored as negative (0%), grade 1 (1%–50%), and grade 2 (51%–100%). Similarly, positive inflammatory cells were graded as negative (0%), grade 1 (1%–10%), and grade 2 (11%–20%). The intensity of each protein expression was simplified as positive or negative. Results A statistically significant correlation exists between the proportions of PD-1 and PD-L1 expression both in papillary carcinoma (p=.001) and peritumoral lymphoid cells in the thyroid (p<.001). In addition, the proportion of PD-L1 expression in PTC cells was closely related to metastatic LNs (p=.036). Conclusions PD-L1 is a valuable predictive marker for LN metastasis in PTC. Immunomodulating therapies that inhibit PD-L1 might be an option for patients with LN metastasis
Factors Associated with Occurrence of Atelectasis during Sedation for Imaging in Pediatric Patients: A Retrospective Single Center Cohort Study
Sedation can induce atelectasis which may cause suboptimal image quality. This study aimed to identify factors associated with the occurrence of atelectasis during sedation for imaging in pediatric patients. Patients < 18 years who had undergone whole-body magnetic resonance imaging (MRI) under sedation with propofol or dexmedetomidine were included in this study. The development of atelectasis was visually and quantitatively assessed by coronal short tau inversion recovery images of the thoracic level. Multivariable logistic regression was performed to identify the independent factors associated with the development of atelectasis. Ninety-one patients were included in the analysis. In the multivariable analysis, administration of supplemental oxygen was the only factor significantly associated with the occurrence of atelectasis (adjusted odds ratio, 4.84; 95% confidence interval, 1.48–15.83; p = 0.009). Univariable analysis showed that the use of dexmedetomidine was associated with a lower incidence of atelectasis; however, this could not be verified in the multivariable analysis. Among the pediatric patients who had undergone imaging under sedation, additional oxygen supplementation was the only independent factor associated with atelectasis occurrence. A prospective clinical trial is required to identify the cause-effect relationship between oxygen administration and occurrence of atelectasis during sedation
Delayed diagnosis of extrapulmonary tuberculosis presenting as fever of unknown origin in an intermediate-burden country
Abstract Background Tuberculosis (TB), especially extrapulmonary tuberculosis (EPTB), is an important cause of fever of unknown origin (FUO) in TB-burdened areas. Little information is known about patients with EPTB with clinical features presenting as FUO and about the factor of delaying the diagnosis. Methods We retrospectively analyzed EPTB patients who were referred with FUO at 3 university-affiliated hospitals over 8 years (2010–2017). The subjects were assigned to groups of early diagnosis and delayed diagnosis within 3 days of an initial comprehensive evaluation from the referral. Clinical and laboratory variables were compared between the groups. Results A total of 95 patients with febrile EPTB were included. Localizing symptoms and/or signs suggestive of anatomy were identified in 62.1% of the patients. Concurrent lung involvement by TB was presented by 49.5% (47/95) of the patients, and only 23.4% of them showed typical findings of pulmonary TB on simple chest X-ray. Most of the patients showed abnormal lesions on cross-sectional CT (98.9%) and MRI (100%). The clinical variables and blood test results of patients were not significantly different between the two groups. The less typical imaging finding of EPTB on CT (38.5% vs. 79.0%) and MRI (37.5% vs. 79.0%) in the delayed diagnosis group was a risk factor for delayed diagnosis. Conclusion Febrile EPTB referred as FUO showed nonspecific clinical manifestations. The active application of cross-sectional imaging tests according to clinical clues or randomly in the absence of local manifestations, combined with invasive diagnostic approaches even for atypical presentations may lead to an earlier diagnosis of febrile EPTB