Search

Purpose: To assess the diagnostic potential of whole-exome sequencing (WES) and elucidate the clinical and genetic characteristics of primary ciliary dyskinesia (PCD) in the Korean population. Materials and Methods: Forty-seven patients clinically suspected of having PCD were enrolled at a tertiary medical center. WES was performed in all patients, and seven patients received biopsy of cilia and transmission electron microscopy (TEM). Results: Overall, PCD was diagnosed in 10 (21.3%) patients: eight by WES (8/47, 17%), four by TEM. Among patients diagnosed as PCD based on TEM results, two patients showed consistent results with WES and TEM of PCD (2/4, 50%). In addition, five patients, who were not included in the final PCD diagnosis group, had variants of unknown significance in PCD-related genes (5/47, 10.6%). The most frequent pathogenic (P)/likely pathogenic (LP) variants were detected in DNAH11 (n=4, 21.1%), DRC1 (n=4, 21.1%), and DNAH5 (n=4, 21.1%). Among the detected 17 P/LP variants in PCD-related genes in this study, 8 (47.1%) were identified as novel variants. Regarding the genotype-phenotype correlation in this study, the authors experienced severe PCD cases caused by the LP/P variants in MCIDAS, DRC1, and CCDC39. Conclusion: Through this study, we were able to confirm the value of WES as one of the diagnostic tools for PCD, which increases with TEM, rather than single gene tests. These results will prove useful to hospitals with limited access to PCD diagnostic testing but with relatively efficient in-house or outsourced access to genetic testing at a pre-symptomatic or early disease stage. [ABSTRACT FROM AUTHOR]

Purpose: To obtain validated clinical values suitable for developing a gustatory function test, including umami taste, in a Korean population. Materials and Methods: The investigation involved 297 participants with self-reported normal sense of taste and smell. Liquid solutions were used for the assessment of gustatory function. The test consisted of 30 taste solutions [six concentrations of five tastants (sweet, bitter, salty, sour, and umami)]. For evaluation of overall gustatory function, the number of detected or correctly recognized taste thresholds was combined to form a "taste score." Results: Mean values of each detection and recognition threshold for the five tastes in men were consistently lower than those of women. The 10th percentile of taste score for recognition was used as the cut-off value for distinguishing normogeusia from hypogeusia. In subgroup analysis, total taste score from recognition thresholds revealed a significant negative correlation with age, indicating lower scores for increasing age. Taste score for non-smokers was significantly higher than that of smokers, in terms of detection and recognition of taste sensitivities. Conclusion: This gustatory function test was easy to perform, affordable, and time-saving, with the capacity to self-produce and obtain reliable data. Gustatory function was more sensitive in young people, women, and non-smokers. [ABSTRACT FROM AUTHOR]

The process of moving k nearest neighbor (MkNN) queries has been studied extensively in spatial network databases. Existing state-of-the-art algorithms have focused primarily on handling MkNN queries in undirected and static spatial networks where every edge is undirected and its weight does not change over time. However, little attention has been paid to MkNN queries in directed and dynamic spatial networks where each edge has a particular orientation and its weight may change over time. In this study, we propose a Safe Exit Algorithm, named SEAD, for MkNN queries in Directed and Dynamic spatial networks. The safe region of a moving query object is an area where the movement of the query object does not cause the current kNN set to change. A safe exit point is the contact point between the safe and non-safe regions. Thus, the set of safe exit points constitutes the border of the safe region. Before reaching a safe exit point, the query object is not required to request that the server reevaluate the ANN query. This significantly reduces the communication and computational costs between the server and query objects. We also introduce the concept of influential region to guarantee the validity of safe regions in dynamic spatial networks. The results of our experiments using real- life road maps confirm the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Reverse K-Nearest Neighbor (RKNN) queries in road networks have been studied extensively in recent years. However, at present, there is still a lack of algorithms for moving queries in a road network. In this paper, we study how to efficiently process moving queries. Existing algorithms do not efficiently handle query movement. For instance, whenever a query changes its location, the result of the query has to be recomputed. To avoid this recomputation, we introduce a new technique that can efficiently compute the safe exit points for continuous RKNNs. Within these safe exit points, the query result remains unchanged and a request for recomputation of the query does not have to be made to the server. This significantly reduces server processing costs and the communication costs between the server and moving clients. The results of extensive experiments conducted using real road network data indicate that our proposed algorithm significantly reduces communication and computation costs. [ABSTRACT FROM AUTHOR]

Purpose: Resistant hypertension (HTN) occurs in 15-20% of treated hypertensive patients, and 70-80% of resistant hypertensive patients have obstructive sleep apnea (OSA). The characteristics of resistant HTN that predispose patients to OSA have not been reported. Therefore, we aimed to determine the clinical, laboratory, and polysomnographic features of resistant HTN that are significantly associated with OSA. Materials and Methods: Hypertensive patients (n=475) who underwent portable polysomnography were enrolled. The patients were categorized into controlled (n=410) and resistant HTN (n=65) groups. The risk factors for the occurrence of OSA in controlled and resistant hypertensive patients were compared, and independent risk factors that are associated with OSA were analyzed. Materials and Methods: Hypertensive patients (n=475) who underwent portable polysomnography were enrolled. The patients were categorized into controlled (n=410) and resistant HTN (n=65) groups. The risk factors for the occurrence of OSA in controlled and resistant hypertensive patients were compared, and independent risk factors that are associated with OSA were analyzed. Conclusion: The higher prevalence and severity of OSA in resistant HTN may be due to the association of risk factors that are common to both conditions. [ABSTRACT FROM AUTHOR]

Most embedded systems are equipped with flash memory owing to its shock resistance, fast access, and low power consumption. However, some of its distinguishing characteristics, including out-of-place updates, an asymmetric read/write/erase speed, and a limited number of write/erase cycles, make it necessary to reconsider the existing system designs to explore its performance potential. For example, the buffer replacement policy of flash-based systems should not only consider the cache hit ratio, but also the relative heavy write and erase costs that are caused by flushing dirty pages. Most of the recent studies on buffer designs have focused on a Clean-First LRU strategy that evicts clean pages preferentially to reduce the number of writes to flash memory. However, each of them fails to distinguish dirty pages, which may have a different effect on the flash memory. In this paper, we propose a Lazy-Split LRU-based buffer management scheme that not only considers an imbalance of the read and write speeds but also different effects of different dirty pages and frequent changes of the B+-tree index structure caused by intensive overwrites. Specifically, it introduces a semi-clean state to further classify some dirty pages into clean part and dirty part and several efficient replacement policies to reduce the number of B+-tree splits. The experimental results show that our solution outperforms other algorithms including pure LRU and CFDC, and is effective and efficient for improving the performance of B'-tree on flash memory. [ABSTRACT FROM AUTHOR]

Background: Psoriasin is known to be expressed in diverse organs, where it exerts antimicrobial activity. Psoriasin is also involved in the local host defense mechanism against pathogens. We hypothesized that allergy-related T-helper cell type 2 (Th2) cytokines may regulate the expression of psoriasin. Methods: We treated normal human nasal epithelial (NHNE) cells with IL-4 or IL-13. Using human nasal tissues, we compared the expression level of psoriasin. We performed real-time polymerase chain reaction and Western blot assays using NHNE cells. Immunohistochemical staining and Western blot assays were performed with human nasal tissues. Furthermore, we studied the antimicrobial activity of nasal secretions from normal and allergic rhinitis patients. Results: IL-13 markedly down-regulated psoriasin expression at the gene and protein levels in NHNE cells, and it also decreased the amount of psoriasin protein that was secreted into the extracellular compartment in NHNE cells. IL-4 had no statistically significant effect. Results from immunohistochemical staining and Western blot assays shoived that psoriasin expression was decreased in allergic rhinitis patients compared with control subjects. Nasal secretions of allergic rhinitis patients exhibited decreased antimicrobial activity compared with control subjects. Conclusion: We found that Th2 cytokines regulated psoriasin expression in NHNE cells, and psoriasin expression was decreased in allergic rhinitis patients compared with control subjects. The decreased expression of psoriasin may be related to the reduction in antimicrobial capacity of nasal secretions under allergic conditions, resulting in an increase in susceptibility to viruses or bacterial infections. [ABSTRACT FROM AUTHOR]

Purpose: Obstructive sleep apnea (OSA) is considered an independent risk factor for hypertension. However, it is still not clear which clinical factors are related with the presence of hypertension in OSA patients. We aimed to find different physical features and compare the sleep study results which are associated with the occurrence of hypertension in OSA patients. Materials and Methods: Medical records were retrospectively reviewed for patients diagnosed with OSA at Severance Cardiovascular Hospital between 2010 and 2013. Males with moderate to severe OSA patients were enrolled in this study. Clinical and polysomnographic features were evaluated to assess clinical variables that are significantly associated with hypertension by statistical analysis. Results: Among men with moderate to severe OSA, age was negatively correlated with hypertension (odds ratio=0.956), while neck circumference was positively correlated with the presence of hypertension (odds ratio=1.363). Among the polysomnographic results, the lowest O2 saturation during sleep was significantly associated with the presence of hypertension (odds ratio=0.900). Conclusion: Age and neck circumference should be considered as clinically significant features, and the lowest blood O2 saturation during sleep should be emphasized in predicting the coexistence or development of hypertension in OSA patients. [ABSTRACT FROM AUTHOR]