1,604 research outputs found
Non-Classical Crystallization of Thin Films and Nanostructures in CVD Process
Non-classical crystallization, where crystals grow by the building blocks of nanoparticles, has become a significant issue not only in solution but also in the gas phase synthesis such as chemical vapor deposition (CVD). Recently, non-classical crystallization was observed in solution in-situ by transmission electron microscope (TEM) using a liquid cell technique. In various CVD processes, the generation of charged nanoparticles (CNPs) in the gas phase has been persistently reported. Many evidences supporting these CNPs to be the building blocks of thin films and nanostructures were reported. According to non-classical crystallization, many thin films and nanostructures which had been believed to grow by individual atoms or molecules turned out to grow by the building blocks of CNPs. The purpose of this paper is to review the development and the main results of non-classical crystallization in the CVD process. The concept of non-classical crystallization is briefly described. Further, it will be shown that the puzzling phenomenon of simultaneous diamond deposition and graphite etching, which violates the second law of thermodynamics when approached by classical crystallization, can be approached successfully by non-classical crystallization. Then, various aspects of non-classical crystallization in the growth of thin films and nanostructures by CVD will be described
Antimicrobial, Antioxidative, Elastase and Tyrosinase Inhibitory Effect of Supercritical and Hydrothermal Halopteris scoparia Extract
To find out a good candidate of cosmetic source and screened for antimicrobial, antioxidant and whitening activities. In the antioxidant experiment, supercritical Halopteris scoparia extraction (SHE) and hydrothermal Halopteris scoparia extraction (HHE) were slightly different depending on the experimental method (Total polyphenol content measurement, DPPH radical scavenging ability, ABTS radical scavenging ability, and SOD-like activity) and in the enzyme experiment (Elastase, Tyrosinase inhibition activity), the supercritical extract was more effective. In supercritical fluid, Halopteris scoparia extracts showed good antimicrobial activity against Propionibacterium acnes, Staphylococcus aureus, Bacillus subtilis and Escherichia coli but hydrothermal extract had no effect about the rest of the strains. Therefore, it can be expected that the supercritical Halopteris scoparia extract with excellent antibacterial activity can be used as a cosmetic material
Mild Hypothermia Attenuates Intercellular Adhesion Molecule-1 Induction via Activation of Extracellular Signal-Regulated Kinase-1/2 in a Focal Cerebral Ischemia Model
Intercellular adhesion molecule-1 (ICAM-1) in cerebral vascular endothelium induced by ischemic insult triggers leukocyte infiltration and inflammatory reaction. We investigated the mechanism of hypothermic suppression of ICAM-1 in a model of focal cerebral ischemia. Rats underwent 2 hours of middle cerebral artery occlusion and were kept at 37°C or 33°C during occlusion and rewarmed to normal temperature immediately after reperfusion. Under hypothermic condition, robust activation of extracellular signal-regulated kinase-1/2 (ERK1/2) was observed in vascular endothelium of ischemic brain. Hypothermic suppression of ICAM-1 was reversed by ERK1/2 inhibition. Phosphorylation of signal transducer and activator of transcription 3 (STAT3) in ischemic vessel was attenuated by hypothermia. STAT3 inhibitor suppressed ICAM-1 production induced by stroke. ERK1/2 inhibition enhanced phosphorylation and DNA binding activity of STAT3 in hypothermic condition. In this study, we demonstrated that hypothermic suppression of ICAM-1 induction is mediated by enhanced ERK1/2 activation and subsequent attenuation of STAT3 action
Severe recurrent nocturnal hypoglycemia during chemotherapy with 6-mercaptopurine in a child with acute lymphoblastic leukemia
Various endocrine dysfunctions occur during chemotherapy, including hypoglycemia. However, reports of hypoglycemia associated with 6-mercaptopurine (6-MP) are rare. Herein, we report an 8-year-old boy with severe symptomatic hypoglycemia likely due to 6-MP during chemotherapy. He had been diagnosed with acute lymphoblastic leukemia 3 years previously and was in the maintenance chemotherapy period. Treatment included oral dexamethasone, methotrexate, and 6-MP, of which only 6-MP was administered daily. Hypoglycemic symptoms appeared mainly at dawn, and his serum glucose dropped to a minimum of 37 mg/dL. Laboratory findings showed nothing specific other than increased serum cortisol, free fatty acids, ketone, alanine aminotransferase, and aspartate aminotransferase. Under the hypothesis of hypoglycemia due to chemotherapy drugs, we changed the time of 6-MP from evening to morning and recommended him to ingest carbohydrate-rich foods before bedtime. Hypoglycemia improved dramatically, and there was no further episode during the remaining maintenance chemotherapy period. To the best of our knowledge, this is the first report of this type of hypoglycemia occurring in an Asian child including Korean
Case of seropositive allergic bronchopulmonary aspergillosis in a 10-year-old girl without previously documented asthma
Allergic bronchopulmonary aspergillosis (ABPA) is a hypersensitivity lung disease due to bronchial colonization of Aspergillus fumigatus that occurs in susceptible patients with asthma or cystic fibrosis. A 10-year-old girl was referred to the Department of Pediatric Pulmonology for persistent consolidations on chest radiography. Pulmonary consolidations were observed in the right upper and left lower lobes and were not resolved with a 4-week prescription of broad-spectrum antibiotics. The patient had a history of atopic dermatitis and allergic rhinitis but no history of asthma. She had no fever but produced thick and greenish sputum. Her breathing sounds were clear. On laboratory testing, her total blood eosinophil count was 1,412/mm3 and total serum IgE level was 2,200 kU/L. Aspergillus was isolated in the sputum culture. The A. fumigatus-specific IgE level was 15.4 kU/L, and the Aspergillus antibody test was also positive. A chest computed tomography scan demonstrated bronchial wall thickening and consolidation without bronchiectasis. An antifungal agent was added but resulted in no improvement of pulmonary consolidations after 3 weeks. Pulmonary function test was normal. Methacholine provocation test was performed, revealing bronchial hyperreactivity (PC20=5.31 mg/mL). Although the patient had no history of asthma or bronchiectasis, ABPA-seropositivity was suspected. Oral prednisolone (1 mg/kg/day) combined with antifungal therapy was started. Pulmonary consolidations began decreasing after 1 week of treatment and completely resolved after 1 month. This is the first observed and treated case of seropositive ABPA in Korean children without previously documented asthma
Calcifying Aponeurotic Fibroma with Osseous Involvement of the Finger: a Case Report with Radiologic and US Findings
Calcifying aponeurotic fibroma is a rare soft tissue tumor that occurs in the distal extremities of children and adolescents. We report ultrasound and X-ray findings of a calcifying aponeurotic fibroma in the finger of a 36-year-old woman, associated with distal phalangeal bone involvement
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