Recently, various attempts have been made to apply diverse types of nanoparticles in biotechnology. Silica nanoparticles (SNPs) have been highlighted and studied for their selective accumulation in diseased parts, strong physical and chemical stability, and low cytotoxicity. SNPs, in particular, are very suitable for use in drug delivery and bioimaging, and have been sought as a treatment for ischemic diseases. In addition, mesoporous silica nanoparticles have been confirmed to efficiently deliver various types of drugs owing to their porous structure. Moreover, there have been innovative attempts to treat ischemic diseases using SNPs, which utilize the effects of Si ions on cells to improve cell viability, migration enhancement, and phenotype modulation. Recently, external stimulus-responsive treatments that control the movement of magnetic SNPs using external magnetic fields have been studied. This review addresses several original attempts to treat ischemic diseases using SNPs, including particle synthesis methods, and presents perspectives on future research directions.

BACKGROUND: To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix. METHODS: We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process. RESULTS: Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results. CONCLUSION With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion.

Background: There has been no comparison of the determinants of admission route between acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We examined whether factors associated with direct versus transferred-in admission to regional cardiocerebrovascular centers (RCVCs) differed between AIS and AMI. Methods: Using a nationwide RCVC registry, we identified consecutive patients presenting with AMI and AIS between July 2016 and December 2018. We explored factors associated with direct admission to RCVCs in patients with AIS and AMI and examined whether those associations differed between AIS and AMI, including interaction terms between each factor and disease type in multivariable models. To explore the influence of emergency medical service (EMS) paramedics on hospital selection, stratified analyses according to use of EMS were also performed. Results: Among the 17,897 and 8,927 AIS and AMI patients, 66.6% and 48.2% were directly admitted to RCVCs, respectively. Multivariable analysis showed that previous coronary heart disease, prehospital awareness, higher education level, and EMS use increased the odds of direct admission to RCVCs, but the odds ratio (OR) was different between AIS and AMI (for the first 3 factors, AMI > AIS; for EMS use, AMI < AIS). EMS use was the single most important factor for both AIS and AMI (OR, 4.72 vs. 3.90). Hypertension and hyperlipidemia increased, while living alone decreased the odds of direct admission only in AMI;additionally, age (65–74 years), previous stroke, and presentation during non-working hours increased the odds only in AIS. EMS use weakened the associations between direct admission and most factors in both AIS and AMI. Conclusions Various patient factors were differentially associated with direct admission to RCVCs between AIS and AMI. Public education for symptom awareness and use of EMS is essential in optimizing the transportation and hospitalization of patients with AMI and AIS.

Background: Tuberculous meningitis (TBM) is the most severe form of tuberculosis, but differentiating between the diagnosis of TBM and viral meningitis (VM) is difficult. Thus, we have developed machine-learning modules for differentiating TBM from VM.Material and Methods: For the training data, confirmed or probable TBM and confirmed VM cases were retrospectively collected from five teaching hospitals in Korea between January 2000 - July 2018. Various machine-learning algorithms were used for training. The machinelearning algorithms were tested by the leave-one-out cross-validation. Four residents and two infectious disease specialists were tested using the summarized medical information. Results: The training study comprised data from 60 patients with confirmed or probable TBM and 143 patients with confirmed VM. Older age, longer symptom duration before the visit, lower serum sodium, lower cerebrospinal fluid (CSF) glucose, higher CSF protein, and CSF adenosine deaminase were found in the TBM patients. Among the various machinelearning algorithms, the area under the curve (AUC) of the receiver operating characteristics of artificial neural network (ANN) with ImperativeImputer for matrix completion (0.85; 95% confidence interval 0.79 - 0.89) was found to be the highest. The AUC of the ANN model was statistically higher than those of all the residents (range 0.67 - 0.72, P <0.001) and an infectious disease specialist (AUC 0.76; P = 0.03). Conclusion The machine-learning techniques may play a role in differentiating between TBM and VM. Specifically, the ANN model seems to have better diagnostic performance than the non-expert clinician.

Background: Tuberculous meningitis (TBM) is the most severe form of tuberculosis, but differentiating between the diagnosis of TBM and viral meningitis (VM) is difficult. Thus, we have developed machine-learning modules for differentiating TBM from VM.Material and Methods: For the training data, confirmed or probable TBM and confirmed VM cases were retrospectively collected from five teaching hospitals in Korea between January 2000 - July 2018. Various machine-learning algorithms were used for training. The machinelearning algorithms were tested by the leave-one-out cross-validation. Four residents and two infectious disease specialists were tested using the summarized medical information. Results: The training study comprised data from 60 patients with confirmed or probable TBM and 143 patients with confirmed VM. Older age, longer symptom duration before the visit, lower serum sodium, lower cerebrospinal fluid (CSF) glucose, higher CSF protein, and CSF adenosine deaminase were found in the TBM patients. Among the various machinelearning algorithms, the area under the curve (AUC) of the receiver operating characteristics of artificial neural network (ANN) with ImperativeImputer for matrix completion (0.85; 95% confidence interval 0.79 - 0.89) was found to be the highest. The AUC of the ANN model was statistically higher than those of all the residents (range 0.67 - 0.72, P <0.001) and an infectious disease specialist (AUC 0.76; P = 0.03). Conclusion The machine-learning techniques may play a role in differentiating between TBM and VM. Specifically, the ANN model seems to have better diagnostic performance than the non-expert clinician.

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

PURPOSE: The traumatic transection is located in the normal sized aortic isthmus where the angle is curved. We found a reversal of upper and lower blood pressure differences among patients who underwent thoracic endovascular aortic repair (TEVAR) for transection of the thoracic aorta. We investigated the isthmus stenosis in patients who underwent TEVAR for aortic injury using computed tomography. MATERIALS AND METHODS: Sixteen patients who underwent TEVAR for transection were divided in two groups: the aortic narrowing (AN) group and the non-aortic narrowing (NAN) group. AN was defined as stent graft folding more than 5 mm at the isthmus confirmed by computed tomography. The length of aorta at isthmus, pseudoaneurysm, and angle of isthmus were measured. RESULTS: AN was noted in five patients (31.3%). The area index in the NAN group (2.16±0.35 cm2/m2) was larger than that in the AN group (1.74±0.77 cm2/m2). The size of the pseudoaneurysm in the NAN group (31.9±4.2 mm) was smaller than that in the AN group (37.4±7.5 mm). The distance from the subclavian artery in the NAN group (15.7±9.3 mm) was longer than that in the AN group (8.4±3.2 mm) but not statistically significant. The angle of the isthmus in the NAN group (131±6 degrees) was larger than that in the AN group (107±3 degrees), and this was the only statistically significant difference (P=0.002). CONCLUSION: AN by stent graft folding should be considered when performing TE-VAR in aortic injury with an acute angle of the isthmus less than 110 degrees.
Aneurysm, False ; Aorta ; Aorta, Thoracic ; Blood Pressure ; Blood Vessel Prosthesis ; Constriction, Pathologic ; Endovascular Procedures ; Humans ; Subclavian Artery ; Thoracic Injuries

BACKGROUND/AIMS: This study analyzed the diagnostic accuracy of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for pancreatic solid masses in patients with or without chronic pancreatitis as well as the clinical parameters relevant to a malignancy when EUS-FNA was negative or inconclusive. METHODS: A total of 97 patients, who underwent EUS-FNA for solid pancreatic masses over 2 years at a single institution, were evaluated. All patients underwent EUS-FNA for 3-5 passes with 22 or 25 G needles without an on-site cytopathologist. The final diagnosis was obtained by surgery or compatible clinical outcomes for a more than 12 month follow-up. The diagnostic yields in the patients with or without chronic pancreatitis were compared and the histories and laboratory data relevant to pancreatic ductal adenocarcinoma (PDAC) or pseudo-tumor were analyzed. RESULTS: The final diagnoses were adenocarcinoma in 88 patients (90.7%) and inflammatory pseudo-tumor in 9 (9.3%). The results of EUS-FNA were adenocarcinoma (74), suspicious (7), atypical (5), negative (10), and inadequate specimen (1). The diagnostic accuracies were 76.9% and 91.6% in patients with or without chronic pancreatitis, respectively. Among the 23 cases with non-diagnostic results of EUS-FNA, PDAC was finally diagnosed in 5 out of 7 suspicious, 3 out of 5 atypical, and 5 out of 10 negative cytology cases. The clinical parameters related to a pseudo-tumor were a history of alcohol consumption and pancreatitis, and normal alkaline phosphatase levels. CONCLUSIONS: The diagnostic accuracy of pancreatic masses in the background of chronic pancreatitis was low. When EUS-FNA produced inconclusive results, the histories of alcohol consumption, pancreatitis, and serum levels of alkaline phosphatase are useful for making a final diagnosis.
Adenocarcinoma ; Alcohol Drinking ; Alkaline Phosphatase ; Biopsy, Fine-Needle* ; Diagnosis ; Endoscopic Ultrasound-Guided Fine Needle Aspiration ; Endosonography ; Follow-Up Studies ; Humans ; Needles ; Pancreatic Ducts ; Pancreatic Neoplasms ; Pancreatitis ; Pancreatitis, Chronic

OBJECTIVE: Productivity loss was compared by 3-stage of disease activity and associations between higher disease activity and high productivity loss were identified. METHODS: Data were extracted from Rheumatoid Arthritis (RA) Patient-reported Outcomes Research, which enrolled 2,000 RA patients (>20-year) on disease-modifying-antirheumatic-drugs (DMARDs) (≥6-month) from December 2012 to June 2013. This included 1,457 RA patients with the disease activity score (DAS-28-ESR) in their medical charts. Productivity loss in time and indirect cost was estimated using The World Health Organization Health and Work Performance Questionnaire (HPQ). Baseline characteristics and productivity loss outcomes were compared according to DAS-28-ESR groups. RESULTS: 84.4% were females, 54.2% had low DAS-28-ESR ( < 3.2), and 38.2% and 7.6% had moderate (3.2∼5.1) and high DAS-28-ESR (>5.1). Patients with moderate to high DAS-28-ESR had higher lost productivity time (LPT) and monthly costs of LPT than those with low DAS-28-ESR (time in hours: 110.0±58.4 vs. 132.4±57.2 vs. 71.5±52.0, p < 0.0001; monthly costs of LPT in 1,000 Korean won: 1,097±607 vs. 1,302±554 vs. 741±531, p < 0.0001). Multiple regression analyses revealed significant associations with high LPT in high (adjusted odds ratio [OR]=3.87, 95% confidence interval [CI]: 2.18∼6.87) and moderate DAS-28-ESR (adjusted OR=1.88, 95% CI: 1.41∼2.52) compared to low DAS-28-ESR. In addition, positive associations with high monthly costs of LPT were observed in high (adjusted OR=3.45, 95% CI: 1.98∼5.99) and moderate DAS-28-ESR (adjusted OR=1.93, 95% CI: 1.43∼2.54) compared to low DAS-28-ESR. CONCLUSION: Timely therapeutic strategies should be taken into consideration given that the RA patients with moderate to high DAS-28-ESR showed strong associations with high productivity loss for effective management of RA.
Arthritis, Rheumatoid* ; Efficiency* ; Female ; Humans ; Odds Ratio ; Outcome Assessment (Health Care) ; Work Performance ; World Health Organization