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Find video protocols related to scientific articles indexed in Pubmed.
Mutagenicity and tumor-promoting effects of Tiglium seed extract via PKC and MAPK signaling pathways.
Biosci. Biotechnol. Biochem.
PUBLISHED: 11-14-2014
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Tiglium seed is a seed of mature Croton Tiglium Linne containing croton oils, which have been traditionally used as laxative or purgative. As it contains phorbol derivatives, we investigated the mutagenicity and tumor-promoting activity of Tiglium seed. Tiglium seed extract produced the mutagenic responses in five Salmonella typhimurium strains in Ames assay, whereas it did not alter the frequencies of chromosomal aberrations or micronuclei, indicating that it exerted the mutagenic potential, not clastogenicity. Accompanied with phosphorylation of connexin43 (Cx43) and extracellular signal-regulated kinases 1/2 (ERK1/2), Tiglium seed extract inhibited gap junctional intercellular communication (GJIC) associated with tumor-promoting potential. Importantly, these effects were blocked by a protein kinase C (PKC) inhibitor or mitogen-activated protein kinase (MAPKs) inhibitors, suggesting that Tiglium seed-induced GJIC inhibition was regulated by phosphorylation of Cx43 via PKC and MAPKs signaling. In conclusion, Tiglium seed has mutagenicity, possibly linking to tumor-promoting potential through the dysfunction of GJIC.
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Trabecular bone score as an indicator for skeletal deterioration in diabetes.
J. Clin. Endocrinol. Metab.
PUBLISHED: 11-05-2014
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Context: Trabecular bone score (TBS) is a novel texture index that evaluates pixel gray-level variations in lumbar spine dual energy X-ray absorptiometry (DXA) images, and is related to bone microarchitecture independent of bone mineral density (BMD). Objective: We investigated lumbar spine TBS as an indicator for skeletal deterioration in diabetes. Design and Setting: Cross-sectional data were collected from subjects participating in an ongoing prospective community-based cohort study from 2009 to 2010. Participants: We included 1,229 men and 1,529 postmenopausal women over 50 years old in the Ansung cohort. Outcome: measures: Biochemical parameters, lumbar spine TBS and BMD from DXA image were measured. Results: Lumbar spine TBS was lower in men with diabetes than in non-diabetic men (1.287 ± 0.005 vs. 1.316 ± 0.003, p<0.001), whereas lumbar spine BMD was higher in men with diabetes (1.135 ± 0.010 vs.1.088 ± 0.006 g/cm(2)). Lumbar spine TBS was lower in women with diabetes than in non-diabetic women only in an unadjusted model (1.333 ± 0.004 vs. 1.353 ± 0.003). However, women <65 years (n=707) with diabetes had lower TBS than those without diabetes even after adjusted for covariates (p<0.001). Diabetes was not associated with BMD at femur sites in both genders. TBS was negatively correlated with HbA1c, fasting plasma glucose, fasting insulin, and homeostasis model assessment -insulin resistance (HOMA-IR), but not with HOMA-? cell function in both genders. Conclusions: The inverse association between lumbar spine TBS and insulin resistance may make it an indicator for determining skeletal deterioration in diabetic patients who have high BMD.
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Recent developments and directions in printed nanomaterials.
Nanoscale
PUBLISHED: 11-05-2014
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In this review, we survey several recent developments in printing of nanomaterials for contacts, transistors, sensors of various kinds, light-emitting diodes, solar cells, memory devices, and bone and organ implants. The commonly used nanomaterials are classified according to whether they are conductive, semiconducting/insulating or biological in nature. While many printing processes are covered, special attention is paid to inkjet printing and roll-to-roll printing in light of their complexity and popularity. In conclusion, we present our view of the future development of this field.
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Triblock cylinders at fluid-fluid interfaces.
Langmuir
PUBLISHED: 11-04-2014
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We present the interactions and assembly of triblock cylinders at oil-water and air-water interfaces. ABA-type triblock cylinders with different block ratios and surface wettabilities are prepared using a micromolding method. These triblock cylinders at fluid-fluid interfaces induce complex interface deformation depending upon their relative block ratio and the surface wettability. It is observed that triblock cylinders generate octapolar interface deformation at the air-water interface, whereas the same cylinders cause quadrupolar deformation at the oil-water interface. Consequently, the interactions and assembly behavior of these triblock cylinders at each fluid interface strongly depend upon the nature of the interface deformation.
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Small angle neutron scattering study of complex coacervate micelles and hydrogels formed from ionic diblock and triblock copolymers.
J Phys Chem B
PUBLISHED: 11-03-2014
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A complex coacervate is a fluid phase that results from the electrostatic interactions between two oppositely charged macromolecules. The nature of the coacervate core structure of hydrogels and micelles formed from complexation between pairs of diblock or triblock copolymers containing oppositely charged end-blocks as a function of polymer and salt concentration was investigated. Both ABA triblock copolymers of poly[(allyl glycidyl ether)-b-(ethylene oxide)-b-(allyl glycidyl ether)] and analogous poly[(allyl glycidyl ether)-b-(ethylene oxide)] diblock copolymers, which were synthesized to be nearly one-half of the symmetrical triblock copolymers, were studied. The poly(allyl glycidyl ether) blocks were functionalized with either guanidinium or sulfonate groups via postpolymerization modification. Mixing of oppositely charged block copolymers resulted in the formation of nanometer-scale coacervate domains. Small angle neutron scattering (SANS) experiments were used to investigate the size and spacing of the coacervate domains. The SANS patterns were fit using a previously vetted, detailed model consisting of polydisperse core-shell micelles with a randomly distributed sphere or body-centered cubic (BCC) structure factor. For increasing polymer concentration, the size of the coacervate domains remained constant while the spatial extent of the poly(ethylene oxide) (PEO) corona decreased. However, increasing salt concentration resulted in a decrease in both the coacervate domain size and the corona size due to a combination of the electrostatic interactions being screened and the shrinkage of the neutral PEO blocks. Additionally, for the triblock copolymers that formed BCC ordered domains, the water content in the coacervate domains was calculated to increase from approximately 16.8% to 27.5% as the polymer concentration decreased from 20 to 15 wt %.
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Acute pulmonary complications in patients with hematologic malignancies.
Radiographics
PUBLISHED: 10-14-2014
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Various acute pulmonary complications may occur in patients with hematologic malignancies because they are in an immunocompromised state due to systemic disease or to chemotherapy or hematopoietic stem cell transplantation. Pulmonary complications may arise from other treatment regimens, as well, or from direct pulmonary involvement in the malignant disease process. The differential diagnosis of pulmonary opacities in patients with hematologic malignancies is broad and includes both infectious and noninfectious causes. Pulmonary hemorrhage, edema, leukostasis, and pneumonia are well-known and common acute pulmonary complications. Less common complications are now encountered with increasing frequency because of the increasing complexity of therapeutic regimens for hematologic malignancies, which may include various drugs that are in clinical trials or were recently released to market. These once uncommon acute pulmonary complications include retinoic acid syndrome, tyrosine kinase inhibitor-induced pulmonary complications, engraftment syndrome, and hemophagocytic lymphohistiocytosis. It is often difficult to differentiate between these entities. However, the clinical setting and radiologic imaging findings may provide clues for interpreting imaging findings of abnormal pulmonary opacity in patients with a hematologic malignancy. Pulmonary hemorrhage is characterized by a sudden onset of symptoms and rapid progression of pulmonary imaging abnormalities and usually occurs in patients with impaired coagulation or a predisposition to bleed. Pulmonary edema should be considered when typical findings of hydrostatic pulmonary edema are seen. Pulmonary leukostasis develops in patients with hyperleukocytosis and leads to symptoms such as a cough, fever, and dyspnea. Various types of pneumonia may develop, depending on the degree and duration of immunosuppression in the patient. Retinoic acid syndrome, tyrosine kinase inhibitor-induced pulmonary complications, and engraftment syndrome occur after specific treatments, so a detailed medical history including recent or current treatments may be helpful for diagnosis. Accurate differentiation of these entities allows their appropriate management, with resultant decreases in morbidity and mortality. ©RSNA, 2014.
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Tunable Volatile Organic Compounds Sensor by Using Thiolated Ligand Conjugation on MoS2.
Nano Lett.
PUBLISHED: 09-11-2014
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One of the most important issues in the development of gas sensors for breath analysis is the fabrication of gas sensor arrays that possess different responses for recognizing patterns for volatile organic compounds (VOCs). Here, we develop a high-performance chemiresistor with a tunable sensor response and high sensitivity for representative VOC groups by using molybdenum disulfide (MoS2) and by conjugating a thiolated ligand (mercaptoundecanoic acid (MUA)) to MoS2 surface. Primitive and MUA-conjugated MoS2 sensing channels exhibit distinctly different sensor responses toward VOCs. In particular, the primitive MoS2 sensor presents positive responses for oxygen-functionalized VOCs, while the MUA-conjugated MoS2 sensor presents negative responses for the same analytes. Such characteristic sensor responses demonstrate that ligand conjugation successfully adds functionality to a MoS2 matrix. Thus, this will be a promising approach to constructing a versatile sensor array, by conjugating a wide variety of thiolated ligands on the MoS2 surface. Furthermore, these MoS2 sensors in this study exhibit high sensitivity to representative VOCs down to a concentration of 1 ppm. This approach to fabricating a tunable and sensitive VOC sensor may lead to a valuable real-world application for lung cancer diagnosis by breath analysis.
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Enhanced transparency, mechanical durability, and antibacterial activity of zinc nanoparticles on glass substrate.
Sci Rep
PUBLISHED: 09-03-2014
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Homogeneously distributed zinc nanoparticles (NPs) on the glass substrate were investigated for the transmittance, mechanical durability, and antibacterial effect. The buffered Ti NPs between Zn NPs and glass substrate were studied for an enhancement of the transmittance and mechanical endurance. The Ti NPs buffered Zn NPs showed a high transmittance of approximately 91.5% (at a wavelength of 550 nm) and a strong antibacterial activity for Staphylococcus aureus and Escherichia coli bacteria. The buffered Ti NPs are attractive for an excellent mechanical endurance of the Zn NPs. The Zn NPs did not require the protection layer to prevent the degradation of the performance for both the antibacterial effect and the transmittance.
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Effect of heated humidified ventilation on bronchial mucus transport velocity in general anaesthesia: A randomized trial.
J. Int. Med. Res.
PUBLISHED: 09-02-2014
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To evaluate the effects of heated humidified ventilation on mucociliary function during general anaesthesia.
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Association between Appendicular Fat Mass and Metabolic Risk Factors.
Korean J Fam Med
PUBLISHED: 07-25-2014
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Different regional fat depots have different effects on lipid and glucose metabolism. The purpose of this study is to examine the relationship between body fat distribution as measured by dual-energy X-ray absorptiometry (DEXA) and metabolic risk factors and to disclose whether there is any difference between groups with and without metabolic syndrome (MS).
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Dynamics of alloplastic bone grafts on an early stage of corticotomy-facilitated orthodontic tooth movement in beagle dogs.
Biomed Res Int
PUBLISHED: 07-22-2014
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Alveolar augmented corticotomy is effective in accelerating orthodontic tooth movement, but the effect only lasts for a relatively short time. Therefore, the purpose of this study was to investigate the underlying biology of the immediate periodontal response to orthodontic tooth movement after a corticotomy with alloplastic bone grafts. The results demonstrated that measurable tooth movement began as early as 3 days after the intervention in beagle dogs. Based on the results and histological findings, augmented corticotomy-facilitated orthodontic tooth movement might enhance the condition of the periodontal tissue and the stability of the outcomes of orthodontic treatment.
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Impact of hyperglycemia on survival and infection-related adverse events in patients with metastatic colorectal cancer who were receiving palliative chemotherapy.
Cancer Res Treat
PUBLISHED: 07-15-2014
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Non-metastatic colorectal cancer patients with diabetes have poor overall survival than those without diabetes. However, the effect of hyperglycemia on survival after diagnosis of metastatic colorectal cancer (CRC) has not been assessed. Therefore, we assessed the impact of hyperglycemia on the survival and infection-related adverse events (AEs) in patients with metastatic CRC.
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Evaluation of radiofrequency exposure levels from multiple wireless installations in population dense areas in Korea.
Bioelectromagnetics
PUBLISHED: 07-09-2014
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This paper presents the results of measurements from simultaneous human exposure to various radiofrequency (RF) signals at densely populated areas. Measurements were performed at 1260 positions across Korea to determine exposure compliance to electromagnetic fields for the general public. The measured exposure levels were very low compared with the international exposure guidelines and Korean human protection notice. The highest total exposure ratio was 5.1?×?10(-3) (approximately 7.1% of guideline limits). Bioelectromagnetics 35:603-606, 2014. © 2014 Wiley Periodicals, Inc.
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Nationwide rate of attention-deficit hyperactivity disorder diagnosis and pharmacotherapy in Korea in 2008-2011.
Asia Pac Psychiatry
PUBLISHED: 06-23-2014
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Using the National Health Insurance database in Korea, we examined the diagnostic and treatment incidence and comorbidity of attention-deficit hyperactivity disorder (ADHD).
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Inhibitory effects of (-)-loliolide on cellular senescence in human dermal fibroblasts.
Arch. Pharm. Res.
PUBLISHED: 06-23-2014
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Cellular senescence influences tumor suppression and progress, tissue repair and regeneration, tissue and organismal aging, and age-related diseases. Aging intervention might be an advantageous target for prevention and treatment of diverse age-related diseases. In this study, we investigated whether (-)-loliolide purified from the crude extract of Polygonum aviculare exerted inhibitory activity against cellular senescence in human dermal fibroblasts (HDFs). (-)-Loliolide diminished senescence-associated ?-galactosidase activity (SA-?-gal), the level of p21 protein, and the level of reactive oxygen species in senescent cells induced by adriamycin treatment. (-)-Loliolide also attenuated SA-?-gal activity in HDFs under replicative senescence. These findings imply that (-)-loliolide rescues cellular senescence in HDFs and might be useful for the development of dietary supplements or cosmetics that ameliorate tissue aging or age-associated diseases.
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Therapeutic hypothermia after cardiac arrest caused by self-inflicted intoxication: a multicenter retrospective cohort study.
Am J Emerg Med
PUBLISHED: 06-11-2014
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The aim of this study was to describe the epidemiology and outcomes of patients with therapeutic hypothermia after out-of-hospital cardiac arrest (OHCA) caused by self-inflicted intoxication.
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Location and characteristics of warfarin associated intracranial hemorrhage.
J Cerebrovasc Endovasc Neurosurg
PUBLISHED: 05-26-2014
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In the so-called primary intracerebral hemorrhage (ICH), lobar and deep ICH were mainly due to cerebral amyloid angiopathy and deep perforating arterial disease. Our aim was to identify specifics of warfarin associated ICH (WAICH) and to focus on differences in susceptibility to warfarin according to the underlying vasculopathies, expressed by ICH location.
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Anti-inflammatory effects of Rubus coreanus Miquel through inhibition of NF-?B and MAP Kinase.
Nutr Res Pract
PUBLISHED: 05-15-2014
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Rubus Coreanus Miquel (RCM), used as a traditional Korean medicine, reduces chronic inflammatory diseases such as cancer and rheumatoid arthritis. However, its mechanism has not been elucidated. In this study, we examine the anti-inflammatory effects of RCM and their possible mechanisms using RAW 264.7 cells.
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The rCBV ratio on perfusion-weighted imaging reveals the extent of blood flow on conventional angiography after acute ischemic stroke.
Clin Neurol Neurosurg
PUBLISHED: 04-03-2014
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In this study, we evaluated the relationship between the rCBV (regional cerebral blood flow volume) ratio on perfusion-weighted imaging (PWI) and the extent of collateral flow on conventional angiography.
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Role of 1D metallic nanowires in polydomain graphene for highly transparent conducting films.
Adv. Mater. Weinheim
PUBLISHED: 04-03-2014
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Upon the addition of silver nanowires (AgNWs), the electrical conductance of graphene film is improved. According to the film's optical birefringence, as shown by studies using liquid crystals (LCs), the improvements do not result from the chemical doping properties of the AgNWs; instead, they arise because the AgNWs facilitate connections among the domains in the graphene film. This is further supported by the film's Dirac point voltage, Raman spectra, and electrical resistance.
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A novel experimental design method to optimize hydrophilic matrix formulations with drug release profiles and mechanical properties.
J Pharm Sci
PUBLISHED: 03-29-2014
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To investigate the effects of hydrophilic polymers on the matrix system, an experimental design method was developed to integrate response surface methodology and the time series modeling. Moreover, the relationships among polymers on the matrix system were studied with the evaluation of physical properties including water uptake, mass loss, diffusion, and gelling index. A mixture simplex lattice design was proposed while considering eight input control factors: Polyethylene glycol 6000 (x1 ), polyethylene oxide (PEO) N-10 (x2 ), PEO 301 (x3 ), PEO coagulant (x4 ), PEO 303 (x5 ), hydroxypropyl methylcellulose (HPMC) 100SR (x6 ), HPMC 4000SR (x7 ), and HPMC 10(5) SR (x8 ). With the modeling, optimal formulations were obtained depending on the four types of targets. The optimal formulations showed the four significant factors (x1 , x2 , x3 , and x8 ) and other four input factors (x4 , x5 , x6 , and x7 ) were not significant based on drug release profiles. Moreover, the optimization results were analyzed with estimated values, targets values, absolute biases, and relative biases based on observed times for the drug release rates with four different targets. The result showed that optimal solutions and target values had consistent patterns with small biases. On the basis of the physical properties of the optimal solutions, the type and ratio of the hydrophilic polymer and the relationships between polymers significantly influenced the physical properties of the system and drug release. This experimental design method is very useful in formulating a matrix system with optimal drug release. Moreover, it can distinctly confirm the relationships between excipients and the effects on the system with extensive and intensive evaluations.
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Descending necrotizing mediastinitis with diffuse ST elevation mimicking pericarditis: a case report.
J Emerg Med
PUBLISHED: 03-12-2014
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Descending necrotizing mediastinitis (DNM) is a potentially fatal disease that requires aggressive treatment, including mediastinal exploration. The inflammation associated with DNM may involve the heart, which produces acute changes in the electrocardiogram (ECG). As a result, the ECG may mimic pericarditis, causing some diagnostic confusion.
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A new type of dental anomaly: molar-incisor malformation (MIM).
Oral Surg Oral Med Oral Pathol Oral Radiol
PUBLISHED: 03-07-2014
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A molar-incisor malformation (MIM) is a newly discovered type of dental anomaly of the permanent first molars, deciduous second molars, and permanent maxillary central incisors. MIM anomalies of the permanent first molars and deciduous second molars may include normal crowns with a constricted cervical region and thin, narrow, and short roots, whereas the affected maxillary central incisors may exhibit a hypoplastic enamel notch near the cervical third of the clinical crown. Although the etiology of MIM remains to be determined, it is thought to be attributable to an epigenetic factor linked to brain- and central nervous system-related systemic diseases at around age 1 to 2 years. MIM teeth are associated with clinical problems such as impaction, early exfoliation, space loss, spontaneous pain, periapical abscess, and poor incisor esthetics. Children with MIM teeth should be observed closely with respect to their medical history, and dentists should formulate a wider-ranging treatment plan.
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A rapid one-step fabrication of patternable superhydrophobic surfaces driven by Marangoni instability.
Langmuir
PUBLISHED: 03-06-2014
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We present a facile and inexpensive approach without any fluorinated chemistry to create superhydrophobic surface with exceptional liquid repellency, transportation of oil, selective capture of oil, optical bar code, and self-cleaning. Here we show experimentally that the control of evaporation is important and can be used to form superhydrophobic surface driven by Marangoni instability: the method involves in-situ photopolymerization in the presence of a volatile solvent and porous PDMS cover to afford superhydrophobic surfaces with the desired combination of micro- and nanoscale roughness. The porous PDMS cover significantly affects Marangoni convection of coating fluid, inducing composition gradients at the same time. In addition, the change of concentration of ethanol is able to produce versatile surfaces from hydrophilic to superhydrophobic and as a consequence to determine contact angles as well as roughness factors. In conclusion, the control of evaporation under the polymerization provides a convenient parameter to fabricate the superhydrophobic surface, without application of fluorinated chemistry and the elegant nanofabrication technique.
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In vitro and in vivo characteristics of stem cells from human exfoliated deciduous teeth obtained by enzymatic disaggregation and outgrowth.
Arch. Oral Biol.
PUBLISHED: 03-04-2014
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Stem cells from human exfoliated deciduous teeth (SHED) are a good source of dental tissue for regeneration therapy, and can be obtained using different primary culture methods. The aim of this study was to determine the differences in the in vitro and in vivo characteristics between SHED isolated via enzymatic disaggregation (e-SHED) and outgrowth (o-SHED) primary culture methods.
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Direct access to a hospital offering intravenous thrombolysis therapy improves functional outcome of acute ischemic stroke patients.
J Clin Neurosci
PUBLISHED: 02-28-2014
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Referral from other hospitals is one of the primary causes of delayed thrombolysis therapy after acute ischemic stroke (AIS). We aimed to evaluate whether direct access to a hospital offering intravenous thrombolysis therapy was associated with good functional outcome in AIS patients treated with thrombolysis. We enrolled patients who received intravenous thrombolysis within 3 hours of symptom onset at our stroke center. We divided these patients into two groups: those with a direct admission to our stroke center and those with indirect admission by referral from other community hospitals. We investigated onset-to-door time and onset-to-recombinant tissue plasminogen activator (rtPA) time according to admission mode. We then assessed the association between a direct admission and favorable outcome at 90 days. A total of 232 patients (mean age of 66.6 years, median National Institutes of Health Stroke Scale score of 10) were included. A total of 48.7% of AIS patients treated with intravenous thrombolytic therapy were transferred from other hospitals. Patients who were directly admitted to our stroke center had a shorter onset-to-door time (61 versus 120 minutes, p<0.001) and onset-to-rtPA time (103 versus 155 minutes, p<0.001) than those referred from other hospitals. Direct admission was associated with a good outcome with an odds ratio of 2.03 (95% confidence interval 1.051-3.917, p=0.035), after adjusting for baseline variables. Thrombolysis after direct admission to a hospital offering intravenous thrombolysis therapy could shorten onset-to-rtPA time and improve stroke outcome in patients with AIS.
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The effect of epigallocatechin-3-gallate (EGCG) on human alveolar bone cells both in vitro and in vivo.
Arch. Oral Biol.
PUBLISHED: 02-15-2014
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The effects of epigallocatechin-3-gallate (EGCG), a major catechin in green tea, on human and mouse osteoblasts remain controversial. This study investigated the direct effects of EGCG on human alveolar bone-derived cells (hABCs) both in vitro and in vivo.
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Comprehensive evaluation of layer separation tendency of novel three-layered tablets with geometric and mechanical properties.
Int J Pharm
PUBLISHED: 02-08-2014
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The layer separation tendency of a novel three-layered matrix tablet was investigated according to various physical properties and novel experiments. Even though layer separation did not occur during manufacturing process and storage, it was observed during a dissolution test depending on the mid-layer formulation. According to the powder properties of the mid-layer substances, Form A, which had higher porosity and lower density than Form B, displayed a tendency of layer separation. These properties correlated with the degree of absorption of the aqueous medium into the mid-layer, which was evaluated by water uptake and mass loss tests. Water uptake and mass loss profiles of the formulations were similar, but the mass loss property of Form A was about 5% higher at the time points, due to the faster dissolution rate of the mid-layer in the first 0.5h. Using a texture analyzer, the layer separation force of the system and adhesion force between the barrier layers were evaluated to understand the correlation between the geometric property and layer separation tendency. During the first 0.5h, the wrapping property of the swollen barrier layers significantly affected the layer separation tendency. The drug release profiles of two formulations could be divided into three stages on the basis of their geometric property as it showed a sigmoid-type. However, for the first stage (about initial 1h in duration), the drug release of Form A was more than Form B due to the mid-layer's powder properties. The results provided valuable information for detailed understanding of issues in the development of a multi-layered system and indicated the importance of a well-designed tablet formulation and manufacturing process.
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Reflectometric interference spectroscopy-based immunosensing using immobilized antibody via His-tagged recombinant protein A.
J. Biosci. Bioeng.
PUBLISHED: 01-23-2014
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The proposed approach demonstrated in this study provides an immunosensing system based on reflectometric interference spectroscopy (RIfS) in combination with an antibody immobilization method using histidine-tagged recombinant protein A. Carboxymethyldextran (CMD) was immobilized on a 3-aminopropyltriethoxysilane-treated a silicon nitride-coated silicon wafer, followed by chelating histidine-tagged recombinant protein A with copper (II) ions. The CMD-layer was found to be advantageous in terms of not only immobilization of histidine-tagged recombinant protein A-mediated an antibody against myoglobin (anti-Myo) but also prevention of non-specific binding of myoglobin. Myoglobin was repeatedly detected, and the apparent detection limit was 0.1 ?g mL(-1). The proposed RIfS-based protein sensing system, in conjunction with the easy preparation of silicon-based inexpensive immunosensing chips, is expected to be applicable for label-free optical detection for other proteins in various fields.
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Transcription factor 7-like 2 (TCF7L2) gene polymorphism rs7903146 is associated with stroke in type 2 diabetes patients with long disease duration.
Diabetes Res. Clin. Pract.
PUBLISHED: 01-15-2014
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Associations between TCF7L2 SNP and diabetic complications and diabetes-related factors were investigated. Subjects with rs7903146 variant had significantly higher prevalence of stroke (24.1% vs. 11.1%; P=0.039) among subjects exhibiting a long disease duration (?10 years). In conclusion, the TCF7L2 SNP variant may confer a higher risk of stroke in diabetic patients.
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Microfluidic design of complex emulsions.
Chemphyschem
PUBLISHED: 01-09-2014
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Controllable generation of complex emulsions comprising exceptional features such as several compartments and shape anisotropy is becoming increasingly important. Complex emulsions are attracting great interest due to their significant potential in many applications, including foods, pharmaceuticals, cosmetics, materials, and chemical separations. Microfluidics is emerging as a promising route to the generation of complex emulsions, providing precise control over emulsion shape, size, and compartments. The aim of this Minireview is to mainly describe the progress of microfluidic approaches to design complex emulsions using hydrodynamic control and phase separation. The emulsions formed are classified according to their morphology, anisotropy, and internal structure. Emerging applications of complex emulsions formed using these microfluidic techniques are discussed.
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Diagnostic Value of Thrombus Size on T2(*)-weighted Gradient Echo Imaging in Acute Middle Cerebral Artery Occlusion.
J Cerebrovasc Endovasc Neurosurg
PUBLISHED: 01-06-2014
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The T2(*)-weighted gradient echo image susceptibility vessel sign (GRE SVS) is a well-known indicator of intraluminal thrombi in acute cerebral infarction. The purpose of this study was to evaluate the relationships between thrombus size on GRE SVS and recanalization after intravenous administration of tissue plasminogen activator (IV-tPA).
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NMR and GC-MS based metabolic profiling and free-radical scavenging activities of Cordyceps pruinosa mycelia cultivated under different media and light conditions.
PLoS ONE
PUBLISHED: 01-01-2014
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Variation of metabolic profiles in Cordyceps pruinosa mycelia cultivated under various media and light conditions was investigated using 1H nuclear magnetic resonance (NMR) analysis and gas chromatography mass spectrometry (GC-MS) with multivariate statistical analysis. A total of 71 metabolites were identified (5 alcohols, 21 amino acids, 15 organic acids, 4 purines, 3 pyrimidines, 7 sugars, 11 fatty acids, and 5 other metabolites) by NMR and GC-MS analysis. The mycelia grown in nitrogen media and under dark conditions showed the lowest growth and ergosterol levels, essential to a functional fungal cell membrane; these mycelia, however, had the highest levels of putrescine, which is involved in abiotic stress tolerance. In contrast, mycelia cultivated in sabouraud dextrose agar with yeast extract (SDAY) media and under light conditions contained relatively higher levels of fatty acids, including valeric acid, stearic acid, lignoceric acid, myristic acid, oleic acid, palmitoleic acid, hepadecenoic acid, and linoleic acid. These mycelia also had the highest phenolic content and antioxidant activity, and did not exhibit growth retardation due to enhanced asexual development caused by higher levels of linoleic acid. Therefore, we suggested that a light-enriched environment with SDAY media was more optimal than dark condition for cultivation of C. pruinosa mycelia as biopharmaceutical or nutraceutical resources.
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High prevalence of low bone mass and associated factors in Korean HIV-positive male patients undergoing antiretroviral therapy.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Low bone mass is prevalent in HIV-positive patients. However, compared to Western countries, less is known about HIV-associated osteopenia in Asian populations.
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Large-scale fabrication of 2-D nanoporous graphene using a thin anodic aluminum oxide etching mask.
J Nanosci Nanotechnol
PUBLISHED: 11-20-2013
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A large-scale nanoporous graphene (NPG) fabrication method via a thin anodic aluminum oxide (AAO) etching mask is presented in this paper. A thin AAO film is successfully transferred onto a hydrophobic graphene surface under no external force. The AAO film is completely stacked on the graphene due to the van der Waals force. The neck width of the NPG can be controlled ranging from 10 nm to 30 nm with different AAO pore widening times. Extension of the NPG structure is demonstrated on a centimeter scale up to 2 cm2. AAO and NPG structures are characterized using optical microscopy (OM), Raman spectroscopy and field-emission scanning electron microscopy (FE-SEM). A field effect transistor (FET) is realized by using NPG. Its electrical characteristics turn out to be different from that of pristine graphene, which is due to the periodic nanostructures. The proposed fabrication method could be adapted to a future graphene-based nano device.
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Preparation of silica-encapsulated ZnSe nanocrystals by mixed surfactant microemulsions.
J Nanosci Nanotechnol
PUBLISHED: 11-20-2013
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Silica-encapsulated ZnSe nanocrystals (NCs) have been prepared by employing sodium (2-ethylhexyl)sulfonate (AOT)/water/cyclohexane microemulsions containing ZnSe quantum dots with polyoxyethylenenonylphenylether (NP5)/water/cyclohexane microemulsions containing tetraethylorthosilicate (TEOS). Size tunable silica nanoparticles were achieved by using various water-to-surfactant ratios, W ([H2O]/[surfactant]). In order to characterize as-synthesized nanocrystals, photoluminescence (PL) spectroscopy, UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) were employed. Cubic zinc blende quantum dots (QDs) (2.5 nm in diameter) were successfully encapsulated by silica nanoparticles (14.3-28.9 nm in diameter). The enhanced photoluminescence efficiency about 10% has been observed when compared with the results from the similar work using AOT microemulsions. The entire size of the silica-encapsulated nanocrystals increased with increasing W, then decreased slightly when free water exists in the core of the NP5/AOT microemulsion. On the other hand, the ZnSe NCs in the silica did not change their size during the synthesis. In addition, the possible mechanisms for growth of silica particles and the kinetics of silica particles formation were discussed.
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Multistage genome-wide association meta-analyses identified two new loci for bone mineral density.
Hum. Mol. Genet.
PUBLISHED: 11-17-2013
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Aiming to identify novel genetic variants and to confirm previously identified genetic variants associated with bone mineral density (BMD), we conducted a three-stage genome-wide association (GWA) meta-analysis in 27 061 study subjects. Stage 1 meta-analyzed seven GWA samples and 11 140 subjects for BMDs at the lumbar spine, hip and femoral neck, followed by a Stage 2 in silico replication of 33 SNPs in 9258 subjects, and by a Stage 3 de novo validation of three SNPs in 6663 subjects. Combining evidence from all the stages, we have identified two novel loci that have not been reported previously at the genome-wide significance (GWS; 5.0 × 10(-8)) level: 14q24.2 (rs227425, P-value 3.98 × 10(-13), SMOC1) in the combined sample of males and females and 21q22.13 (rs170183, P-value 4.15 × 10(-9), CLDN14) in the female-specific sample. The two newly identified SNPs were also significant in the GEnetic Factors for OSteoporosis consortium (GEFOS, n = 32 960) summary results. We have also independently confirmed 13 previously reported loci at the GWS level: 1p36.12 (ZBTB40), 1p31.3 (GPR177), 4p16.3 (FGFRL1), 4q22.1 (MEPE), 5q14.3 (MEF2C), 6q25.1 (C6orf97, ESR1), 7q21.3 (FLJ42280, SHFM1), 7q31.31 (FAM3C, WNT16), 8q24.12 (TNFRSF11B), 11p15.3 (SOX6), 11q13.4 (LRP5), 13q14.11 (AKAP11) and 16q24 (FOXL1). Gene expression analysis in osteogenic cells implied potential functional association of the two candidate genes (SMOC1 and CLDN14) in bone metabolism. Our findings independently confirm previously identified biological pathways underlying bone metabolism and contribute to the discovery of novel pathways, thus providing valuable insights into the intervention and treatment of osteoporosis.
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Characteristics of Ga-Al doped ZnO thin films with plasma treatment prepared by using facing target sputtering method.
J Nanosci Nanotechnol
PUBLISHED: 11-12-2013
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Ga-Al-doped ZnO (GAZO) thin films were prepared on glass substrates using facing targets sputtering at room temperature. GAZO thin films have been treated in O2 plasma to modify surface roughness in order to enhance the efficiency of OLED anodes made from the films. After deposition of the thin films, the substrate was subjected to plasma surface treatment. The electrical, optical, and surface properties of the deposited thin films were investigated by hall-effect measurement, UV/Vis spectrometry, and atomic force microscopy (AFM), respectively. As a result of increasing the plasma treatment time from 0 to 45 sec, the surface roughness of films after plasma treatment was improved, but their electrical, optical, and structural properties were slightly changed. The lowest values of the surface roughness were 1.409 nm for the as-deposited GAZO thin films for an O2 plasma treatment time of 40 sec. All GAZO thin films have an average transmittance of 90% in the visible range (400-800 nm).
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Low-frequency noise in multilayer MoS2 field-effect transistors: the effect of high-k passivation.
Nanoscale
PUBLISHED: 11-11-2013
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Diagnosing of the interface quality and the interactions between insulators and semiconductors is significant to achieve the high performance of nanodevices. Herein, low-frequency noise (LFN) in mechanically exfoliated multilayer molybdenum disulfide (MoS2) (?11.3 nm-thick) field-effect transistors with back-gate control was characterized with and without an Al2O3 high-k passivation layer. The carrier number fluctuation (CNF) model associated with trapping/detrapping the charge carriers at the interface nicely described the noise behavior in the strong accumulation regime both with and without the Al2O3 passivation layer. The interface trap density at the MoS2-SiO2 interface was extracted from the LFN analysis, and estimated to be Nit? 10(10) eV(-1) cm(-2) without and with the passivation layer. This suggested that the accumulation channel induced by the back-gate was not significantly influenced by the passivation layer. The Hooge mobility fluctuation (HMF) model implying the bulk conduction was found to describe the drain current fluctuations in the subthreshold regime, which is rarely observed in other nanodevices, attributed to those extremely thin channel sizes. In the case of the thick-MoS2 (?40 nm-thick) without the passivation, the HMF model was clearly observed all over the operation regime, ensuring the existence of the bulk conduction in multilayer MoS2. With the Al2O3 passivation layer, the change in the noise behavior was explained from the point of formation of the additional top channel in the MoS2 because of the fixed charges in the Al2O3. The interface trap density from the additional CNF model was Nit = 1.8 × 10(12) eV(-1) cm(-2) at the MoS2-Al2O3 interface.
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Ellagic Acid Identified through Metabolomic Analysis Is an Active Metabolite in Strawberry (Seolhyang) Regulating Lipopolysaccharide-Induced Inflammation.
J. Agric. Food Chem.
PUBLISHED: 11-08-2013
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This study employed the metabolomic approach to identify the key constituent exerting anti-inflammatory activity in murine macrophage RAW 264.7 cells. Among the six different fractions (SF1-SF6) of the strawberry Seolhyang, SF4 showed more significant inhibition on iNOS expression than SF3, and ellagic acid was determined as the most significant different component between SF4 and SF3 using orthogonal partial least-squares discriminant analysis. Ellagic acid (0.3 and 1.0 ?M) and SF4 (100 ?g/mL) were found to regulate the same inflammatory mediators, inhibitory ?B (I?B) and mitogen-activated protein kinases (MAPKs), which led to the reduction of tumor necrosis factor (TNF-?), interleukin-1? (IL-1?), and iNOS expressions. These results demonstrate that ellagic acid from strawberry Seolhyang is the major component playing a crucial role in inflammation, suggesting the possible application of metabolomic analysis to determining the key ingredients having biological functions in the complicated food matrix.
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Temporal variation and morphologic characteristics of J-waves in patients with early repolarisation syndrome.
Heart
PUBLISHED: 10-22-2013
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Electrocardiographic markers identifying malignant forms of early repolarisation (ER) from ER of normal variants are of prime clinical importance. We compared the ECG parameters of ER patterns in patients with early repolarisation syndrome (ERS) proximate to the ventricular fibrillation (VF) episodes, remote from the events and those with normal controls with ER.
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Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells.
J. Radiat. Res.
PUBLISHED: 10-08-2013
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The objective of this study was to investigate the effects of the combined RF radiation (837 MHz CDMA plus 1950 MHz WCDMA) signal on levels of intracellular reactive oxygen species (ROS) in neuronal cells. Exposure of the combined RF signal was conducted at specific absorption rate values of 2 W/kg of CDMA plus 2 W/kg of WCDMA for 2 h. Co-exposure to combined RF radiation with either H2O2 or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H2O2 or menadione groups. The intracellular ROS level was measured by flow cytometry using the fluorescent probe dichlorofluorescein diacetate. Intracellular ROS levels were not consistently affected by combined RF radiation exposure alone in a time-dependent manner in U87, PC12 or SH-SY5Y cells. In neuronal cells exposed to combined RF radiation with either H2O2 or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H2O2 alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H2O2 influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y.
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Induction of steroid sulfatase expression in PC-3 human prostate cancer cells by insulin-like growth factor II.
Toxicol. Lett.
PUBLISHED: 09-03-2013
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Human steroid sulfatase (STS) plays an important role in regulating the formation of biologically active estrogens and may be a promising target for treating estrogen-mediated carcinogenesis. The molecular mechanism of STS gene expression, however, is still not clear. Growth factors are known to increase STS activity but the changes in STS expression have not been completely understood. To determine whether insulin-like growth factor (IGF)-II can induce STS gene expression, the effects of IGF-II on STS expression were studied in PC-3 human prostate cancer cells. RT-PCR and Western blot analysis showed that IGF-II treatment significantly increased the expression of STS mRNA and protein in concentration- and time-dependent manners. To understand the signaling pathway by which IGF-II induces STS gene expression, the effects of specific PI3-kinase/Akt and NF-?B inhibitors were determined. When the cells were treated with IGF-II and PI3-kinase/Akt inhibitors, such as LY294002, wortmannin, or Akt inhibitor IV, STS expression induced by IGF-II was significantly blocked. Moreover, we found that NF-?B inhibitors, such as MG-132, bortezomib, Bay 11-7082 or Nemo binding domain (NBD) binding peptide, also strongly prevented IGF-II from inducing STS gene expression. We assessed whether IGF-II activates STS promoter activity using transient transfection with a luciferase reporter. IGF-II significantly stimulated STS reporter activity. Furthermore, IGF-II induced expression of 17?-hydroxysteroid dehydrogenase (HSD) 1 and 3, whereas it reduced estrone sulfotransferase (EST) gene expression, causing enhanced estrone and ?-estradiol production. Taken together, these results strongly suggest that IGF-II induces STS expression via a PI3-kinase/Akt-NF-?B signaling pathway in PC-3 cells and may induce estrogen production and estrogen-mediated carcinogenesis.
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Adenosine Diphosphate-Induced Platelet Aggregation Might Contribute to Poor Outcomes in Atrial Fibrillation-Related Ischemic Stroke.
J Stroke Cerebrovasc Dis
PUBLISHED: 07-30-2013
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Systemic atherosclerosis is involved in ischemic damages and cardioembolism after atrial fibrillation (AF)-related ischemic stroke (IS). Platelet activation is a critical factor in systemic atherosclerosis; however, there is little information regarding the role of platelet activation on the outcome of AF-related IS. We investigated the relationship between adenosine diphosphate (ADP)-induced platelet aggregation and the long-term outcomes of AF-related IS. We studied 249 patients who were exclusively treated with anticoagulation therapy after they had experienced AF-related IS. We evaluated their platelet function 5 days after admission to the hospital by using an optic platelet aggregometer test. We also assessed the prognoses of patients 90 days after the AF-related IS. Our results showed that ADP-induced platelet aggregation was positively correlated with CHA2DS2-VASc scores (r = .285, P < .01). Totally, 107 (43.0%) patients had a poor outcome at 90 days after IS. Univariate analysis showed that the following factors significantly contribute to a poor outcome: older age (odds ratio [OR] = 1.07, confidence interval [CI] 1.04-1.10, P < .01), a history of stroke (OR = 3.24, CI 1.61-6.53, P < .01), high scores on the National Institutes of Health Stroke Scale (NIHSS; OR = 1.25, CI 1.18-1.32, P < .01), increased white blood cell counts (OR = 1.12, CI 1.02-1.24, P < .01), high CHA2DS2-VASc scores (?5, OR = 7.31, CI 3.36-15.93, P = .025), and the highest tertile of ADP-induced platelet aggregation (?72%, OR = 3.17, CI 1.67-5.99, P < .01). Of these factors, high NIHSS scores (OR = 1.27, CI 1.20-1.36, P < .01), high CHA2DS2-VASc scores (OR = 4.69, CI 1.21-18.14, P = .03), and the highest tertile of ADP-induced platelet aggregation (OR = 2.49, CI 1.17-5.27, P = .02) were independently associated with a poor outcome at 90 days after IS. Therefore, our results suggest that platelet activation might affect the outcome of AF-related IS.
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Controllable preparation of monodisperse microspheres using geometrically mediated droplet formation in a single mold.
Langmuir
PUBLISHED: 06-27-2013
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We present a surfactant-free fabrication method for simultaneous generation of monodisperse microspheres with controllable size manner. Droplets that become microspheres by solidification processes are made in a two-step process: capillary rising-induced fluid division and wetting of immiscible fluid in a micromold. Design of the mold geometry and the monomer concentration primarily determines the microsphere size and the size distribution. Furthermore, the synergistic effect of two parameters is able to efficiently manipulate the microsphere sizes from submicrometers to a few hundred micrometers.
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Evaluation of taste-masking effects of pharmaceutical sweeteners with an electronic tongue system.
Drug Dev Ind Pharm
PUBLISHED: 06-20-2013
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Abstract Electronic tongue systems have been developed for taste measurement of bitter drug substances in accurate taste comparison to development palatable oral formulations. This study was to evaluate the taste masking effect of conventional pharmaceutical sweeteners such as neohesperidin dihydrochalcone, sucrose, sucralose and aspartame. The model drugs were acetaminophen, ibuprofen, tramadol hydrochloride, and sildenafil citrate (all at 20?mM). The degree of bitterness was measured by a multichannel taste sensor system (an electronic tongue). The data was collected by seven sensors and analyzed by a statistical method of principal components analysis (PCA). The effect of taste masking excipient was dependent on the type of model drug. Changing the concentration of taste masking excipients affected the sensitivity of taste masking effect according to the type of drug. As the excipient concentration increased, the effect of taste masking increased. Moreover, most of the sensors showed a concentration-dependent pattern of the taste-masking agents as higher concentration provided higher selectivity. This might indicate that the sensors can detect small concentration changes of a chemical in solution. These results suggest that the taste masking could be evaluated based on the data of the electronic tongue system and that the formulation development process could be performed in a more efficient way.
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Nanoporous bicontinuous structures via addition of thermally-stable amphiphilic nanoparticles within block copolymer templates.
ACS Appl Mater Interfaces
PUBLISHED: 06-11-2013
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Herein, we fabricated the bicontinuous structures from nanocomposites of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) block copolymer and the shell-cross-linked, thermally stable gold nanoparticles (Au NPs). The surface property of Au NPs was controlled with ligands containing various compositions of PS and PMMA so that the resulting Au NPs were selective to PS or PMMA block or nonselective (i.e., neutral) to both blocks. The amphiphilic Au NPs were also prepared by coating the surface of Au NPs with equimolar mixtures of PS and PMMA selective ligands. Consequently, it was found that the morphological behaviors of thermally annealed nanocomposites containing amphiphilic Au NPs and PS-b-PMMA were dramatically different from the case of neutral Au NPs that were coated with nonselective ligands. With increasing the amount of amphiphilic Au NPs, a transition from lamellar to bicontinuous structures was observed, whereas the neutral Au NPs were aggregated within the PS-b-PMMA lamellae. Furthermore, the nanoporous bicontinuous thin films were fabricated on the silicon substrates and the morphological behaviors were quantitatively investigated by grazing-incidence small-angle X-ray scattering (GISAXS) analysis.
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A facile synthesis-fabrication strategy for integration of catalytically active viral-palladium nanostructures into polymeric hydrogel microparticles via replica molding.
ACS Nano
PUBLISHED: 05-23-2013
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The synthesis of small, uniform, well-dispersed and active Pd nanocatalysts under mild conditions in a predictable and controlled manner is an unmet challenge. Viral nanomaterials are attractive biotemplates for the controlled synthesis of nanoparticles due to their well-defined and monodisperse structure along with abundant surface functionalities. Here, we demonstrate spontaneous formation of small (1-2 nm), uniform and highly crystalline palladium (Pd) nanoparticles along genetically modified tobacco mosaic virus (TMV1cys) biotemplates without external reducing agents. The ratio between TMV and Pd precursor plays an important role in the exclusive formation of well-dispersed Pd nanoparticles along TMV biotemplates. The as-prepared Pd-TMV complexes are then integrated into the poly(ethylene glycol) (PEG)-based microparticles via replica molding (RM) technique in a simple, robust and highly reproducible manner. High catalytic activity, recyclability and stability of the hybrid Pd-TMV-PEG microparticles are further demonstrated through dichromate reduction as a model reaction. Taken together, these findings demonstrate a significant step toward simple, robust, and scalable synthesis and fabrication of efficient biotemplate-supported Pd nanocatalysts in readily deployable polymeric scaffolds with high capacity in a controlled manner.
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Similar neuroprotective effects of ischemic and hypoxic preconditioning on hypoxia-ischemia in the neonatal rat: a proton MRS study.
Int. J. Dev. Neurosci.
PUBLISHED: 05-14-2013
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The aim of this study was to evaluate the effect of ischemic and hypoxic preconditioning on hypoxia-ischemia (HI) in the neonatal rat. Seven-day-old Sprague-Dawley rats were divided into four groups: control, sham, ischemic preconditioning, and hypoxic preconditioning. Ischemic preconditioning with a 10-min occlusion of the right carotid artery and hypoxic preconditioning with 4-h of hypoxia (8% oxygen) were performed 24-h before HI. For HI, all rats underwent right carotid artery ligature, followed by 2.5-h of hypoxia. Proton magnetic resonance spectroscopy ((1)H MRS) and TUNEL staining were evaluated at 1 and 7 days after HI. At 2 weeks after HI, all rats were sacrificed for morphological analysis. The lipid (Lip), N-acetyl aspartate (NAA), creatine (Cr), and choline-ratios were calculated and compared with TUNEL staining and brain morphologies. Both the ischemic and hypoxic preconditioning groups showed lower Lip/NAA and Lip/Cr ratios and morphological scores, and fewer TUNEL-positive cells than the control and sham groups (P < 0.05). There were no significant differences between the two preconditioning groups. In addition, the ratios correlated with the TUNEL staining and the degrees of morphological changes in all of the groups (P < 0.05). These results suggest that ischemic and hypoxic preconditioning in neonatal rats with HI similarly attenuate brain injury. Moreover, Lip/NAA and Lip/Cr ratios may be used as markers for assessing the extent of brain damage.
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Evaluation of drug delivery profiles in geometric three-layered tablets with various mechanical properties, in vitro-in vivo drug release, and Raman imaging.
J Control Release
PUBLISHED: 05-06-2013
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Even though various multi-layered tablets have been developed for sustained release formulations, evaluations of mechanical properties during dissolution with drug release and imaging in the tablets have been limited. A novel geometric system consisting of an inner immediate release layer and two extended release barrier layers with swellable hydrophilic polymers was suggested as a once-a-day formulation. To evaluate drug release mechanisms with geometric properties, various mechanical characteristics during swelling were investigated to comprehend the relationship among in vitro drug release, human pharmacokinetics, and geometric characteristics. Imaging of drug movement was also studied in real-time using Raman spectroscopy. Drug delivery in the tablets might be divided into three processes through the geometric properties. When exposed to aqueous environments, the drug in the mid-layer was released until wrapped by the swollen barrier layers. Then, the drug in the mid-layer was mainly delivered to the barrier layers and a small amount of the drug was delivered to the contact region of the swollen barrier layers. Finally, the delivered drug to the barrier layers was consistently released out in response to the characteristics of the polymer of the barrier layers. Using Raman spectroscopy, these processes were confirmed in real-time analysis. Moreover, in vitro drug release profiles and human pharmacokinetics showed consistent results suggesting that drug release might be dependent on the various geometric properties and be modified consistently during the formulation development.
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Investigation of polymeric excipients for dutasteride solid dispersion and its physicochemical characterization.
Arch. Pharm. Res.
PUBLISHED: 04-29-2013
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To investigate the effects of polymeric excipients for dutasteride solid dispersion, experimental approaches together with physical interactions at molecular level were evaluated. The drug and various polymers (anionic, amphiphilic, and hydrophilic) were mixed physically into different ratios and their thermodynamic and physical properties were analyzed by differential scanning calorimetry and Fourier transform-infrared spectroscopy, respectively. The enhanced equilibrium solubility of dutasteride was also investigated. Dutasteride is non-ionic and showed low solubility in the tested pH ranges (lower than the detection limit of 20 ng/mL). Kollidon(®) MAE 100P, an anionic polymer, showed enhanced dutasteride solubility in aqueous solution followed by hydrophilic Kollidon(®) SR and the amphiphilic polymer, Soluplus(®). Melting point (T m ) of dutasteride was 249.7 °C and was decreased to 229.84 °C when mixed evenly with Kollidon(®) MAE 100P. However, the melting point was not detected at a ratio of 1:4 since it fully dissolved or dispersed in the polymer. Glass transition temperature (T g ) of different compositions exhibited strong interaction of polymer and drug. The result was supported by spectra evidence that Kollidon(®) MAE 100P forms hydrogen bonds with dutasteride presenting strong physical interaction with the primary amine group of dutasteride. This study supports a convenient method that together with microscopic observation can perform polymer selection and characterize solid dispersions.
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Effects of whole-body exposure to 915?MHz RFID on secretory functions of the thyroid system in rats.
Bioelectromagnetics
PUBLISHED: 04-23-2013
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As a part of an investigation on the potential risks of radiofrequency identification (RFID) on human health, we studied whether exposure to 915?MHz RFID in rats significantly affected the secretory function of the thyroid system. A reverberation chamber was used as a whole-body exposure system. Male Sprague-Dawley rats were exposed for 8?h per day, 5 days per week, for a duration of 2, 4, 8, or 16 weeks. The estimated whole-body average specific absorption rate (SAR) varied from 3.2 to 4.6?W/kg depending on the age/mass of the animals for the field of the 915?MHz RFID reader. Plasma levels of triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) were evaluated via enzyme-linked immunosorbent assay. Morphological changes in the thyroid gland were then analyzed. No changes in T3, T4, or TSH were observed over time between the sham- and RFID-exposed groups. We suggest that subchronic exposure to 915?MHz RFID at a SAR of 4?W/kg does not cause significant effects on thyroid secretory function.
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Prevalence of vitamin d deficiency and effects of supplementation with cholecalciferol in patients with chronic kidney disease.
J Ren Nutr
PUBLISHED: 04-05-2013
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We aimed to evaluate the vitamin D status, the effect of cholecalciferol supplementation, and the factors associated with vitamin D restoration in nondialytic patients with chronic kidney disease (CKD).
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Association of monocyte chemoattractant protein-1 (MCP-1) 2518A/G polymorphism with proliferative diabetic retinopathy in Korean type 2 diabetes.
Yonsei Med. J.
PUBLISHED: 04-04-2013
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Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that can increase adhesion molecule expression on monocytes and produce superoxide anions. Hyperglycemia induces MCP-1 production in vascular endothelial cells and retinal pigmented epithelial cells, and has been implicated as a causal factor in the facilitation of vascular complications in diabetes. In the present study, we evaluated the association of a single nucleotide polymorphism (SNP) in the MCP-1 gene with proliferative diabetic retinopathy (PDR) in a Korean population with type 2 diabetes.
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Direct Relationship between Angiographic Characteristics of Carotid Atherosclerotic Plaque and Filling Defect in the Cerebral Protection Filters : Based on the Conventional Angiography.
J Korean Neurosurg Soc
PUBLISHED: 03-30-2013
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Neurologic complications during carotid artery stenting (CAS) are usually associated with distal embolic event. These embolic incident during CAS are highly associated with the carotid plaque instability. The current study was undertaken to identify the angiographic characteristics of carotid plaque vulnerability, which was represented as filling defect in the cerebral protection filters during CAS.
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Endobronchial Mycobacterium avium Infection in an Immunocompetent Patient.
Infect Chemother
PUBLISHED: 03-29-2013
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Although Mycobacterium avium complex (MAC) is the most common pathogen in nontuberculous mycobacterial (NTM) pulmonary diseases, endobronchial lesions caused by MAC infections are very rare even in an immunocompromised host. Herein, we describe the case of a 59-year-old, HIV-negative and non-immunocompromised woman who developed multifocal pulmonary infiltrations with endobronchial lesion caused by M. avium. Bronchoscopic examination revealed white- and yellow-colored irregular mucosal lesions in the bronchus of the left lingular division. M. avium was identified using sputum culture and bronchial washing fluid culture. Following the recommendations of the American Thoracic Society and Infectious Diseases Society of America (ATS/IDSA), the patient was begun on treatment with antimycobacterial drugs. After treatment, pneumonic infiltration decreased.
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Leptin and urinary leukotriene E4 and 9?,11?-prostaglandin F2 release after exercise challenge.
Ann. Allergy Asthma Immunol.
PUBLISHED: 03-26-2013
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Leptin-related effects on inflammation and bronchial hyperresponsiveness (BHR) in the human airway have not been demonstrated.
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Positive regulation of osteogenesis by bile acid through FXR.
J. Bone Miner. Res.
PUBLISHED: 03-11-2013
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Farnesoid X receptor (FXR) is a nuclear receptor that functions as a bile acid sensor controlling bile acid homeostasis. We investigated the role of FXR in regulating bone metabolism. We identified the expression of FXR in calvaria and bone marrow cells, which gradually increased during osteoblastic differentiation in vitro. In male mice, deletion of FXR (FXR(-/-) ) in vivo resulted in a significant reduction in bone mineral density by 4.3% to 6.6% in mice 8 to 20 weeks of age compared with FXR(+/+) mice. Histological analysis of the lumbar spine showed that FXR deficiency reduced the bone formation rate as well as the trabecular bone volume and thickness. Moreover, tartrate-resistant acid phosphatase (TRACP) staining of the femurs revealed that both the osteoclast number and osteoclast surface were significantly increased in FXR(-/-) mice compared with FXR(+/+) mice. At the cellular level, induction of alkaline phosphatase (ALP) activities was blunted in primary calvarial cells in FXR(-/-) mice compared with FXR(+/+) mice in concert with a significant reduction in type I collagen a1(Col1a1), ALP, and runt-related transcription factor 2 (Runx2) gene expressions. Cultures of bone marrow-derived macrophages from FXR(-/-) mice exhibited an increased number of osteoclast formations and protein expression of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1). In female FXR(-/-) mice, although bone mineral density (BMD) was not significantly different from that in FXR(+/+) mice, bone loss was accelerated after an ovariectomy compared with FXR(+/+) mice. In vitro, activation of FXR by bile acids (chenodeoxycholic acid [CDCA] or 6-ECDCA) or FXR agonists (GW4064 or Fexaramine) significantly enhanced osteoblastic differentiation through the upregulation of Runx2 and enhanced extracellular signal-regulated kinase (ERK) and ?-catenin signaling. FXR agonists also suppressed osteoclast differentiation from bone marrow macrophages. Finally, administration of a farnesol (FOH 1%) diet marginally prevented ovariectomy (OVX)-induced bone loss and enhanced bone mass gain in growing C57BL/6J mice. Taken together, these results suggest that FXR positively regulates bone metabolism through both arms of the bone remodeling pathways; ie, bone formation and resorption.
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Ruptured mycotic aneurysm of the distal middle cerebral artery manifesting as subacute subdural hematoma.
J Cerebrovasc Endovasc Neurosurg
PUBLISHED: 03-10-2013
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Mycotic aneurysms are rare inflammatory neurovascular lesions. Ruptured mycotic aneurysm manifesting as subdural hematoma is extremely rare. A 72-year-old male patient was admitted to our hospital with headache and drowsiness. Computer tomography (CT) of brain and CT angiography revealed subdural hematoma and an aneurysm located at the M4 segment of the left middle cerebral artery (MCA). Cerebral angiogram revealed 2 aneurysms; one located at the left distal MCA and the other at the bifurcation of left MCA. Laboratory studies showed leukocytosis and elevated inflammatory factors. The patent was treated with antibiotic therapy for 4 weeks. The follow-up CT and cerebral angiography showed that the mycotic aneurysm was completely resolved, and the patient was nearly free of symptoms.
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Integrative analysis of time course microarray data and DNA sequence data via log-linear models for identifying dynamic transcriptional regulatory networks.
Int J Data Min Bioinform
PUBLISHED: 02-27-2013
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Since eukaryotic transcription is regulated by sets of Transcription Factors (TFs) having various transcriptional time delays, identification of temporal combinations of activated TFs is important to reconstruct Transcriptional Regulatory Networks (TRNs). Our methods combine time course microarray data, information on physical binding between the TFs and their targets and the regulatory sequences of genes using a log-linear model to reconstruct dynamic functional TRNs of the yeast cell cycle and human apoptosis. In conclusion, our results suggest that the proposed dynamic motif search method is more effective in reconstructing TRNs than the static motif search method.
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reliable Synthesis of Monodisperse Microparticles: Prevention of Oxygen Diffusion and Organic Solvents Using Conformal Polymeric Coating onto Poly(dimethylsiloxane) Micromold.
Langmuir
PUBLISHED: 02-25-2013
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An effective polymeric thin film deposited by initiated chemical vapor deposition (iCVD) process was presented and its application as a barrier film on the PDMS micromold blocking the penetration of oxygen and organic solvents was investigated. With this barrier film, we were able to synthesize monodisperse polymeric particles of sizes down to 3 ?m, which has been reported to be extremely challenging with bare PDMS micromold. The polymeric barrier film on the PDMS micromold enabled this successful synthesis of microparticles by effectively blocking the diffusion of oxygen, which is a well-known radical quencher in radical polymerization, through the PDMS micromold. Furthermore, the iCVD barrier film substantially decreased the penetration of various organic solvents such as acetone, tert-butanol, PDMS oil, and decane as well as organic substances including fluorescent molecules like rhodamine B and fluorescein isothiocyanate (FITC). Therefore, the polymeric barrier film coated on PDMS micromold via iCVD process will broaden the application of PDMS to microfluidic area for the synthesis of smaller microparticles with various organic substances.
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Mobile phone use, blood lead levels, and attention deficit hyperactivity symptoms in children: a longitudinal study.
PLoS ONE
PUBLISHED: 02-21-2013
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Concerns have developed for the possible negative health effects of radiofrequency electromagnetic field (RF-EMF) exposure to childrens brains. The purpose of this longitudinal study was to investigate the association between mobile phone use and symptoms of Attention Deficit Hyperactivity Disorder (ADHD) considering the modifying effect of lead exposure.
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Thermogravimetric characteristics and pyrolysis kinetics of Alga Sagarssum sp. biomass.
Bioresour. Technol.
PUBLISHED: 02-15-2013
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Alga Sagarssum sp. can be converted to bio-oil, gas, and char through pyrolysis. In this study, the pyrolysis characteristics and kinetics of Sagarssum sp. were investigated using a thermogravimetric analyzer and tubing reactor, respectively. Sagarssum sp. decomposed below 550°C, but the majority of materials decomposed between 200 and 350°C at heating rates of 5-20°C/min. The apparent activation energy increased from 183.53 to 505.57 kJ mol(-1) with increasing pyrolysis conversion. The kinetic parameters of Sagarssum sp. pyrolysis were determined using nonlinear least-squares regression of the experimental data, assuming second-order kinetics. The proposed lumped kinetic model represented the experimental results well and the kinetic rate constants suggested a predominant pyrolysis reaction pathway from Sagarssum sp. to bio-oil, rather than from Sagarssum sp. to gas. The kinetic rate constants indicated that the predominant reaction pathway was A (Sagarssum sp.) to B (bio-oil), rather than A (Sagarssum sp.) to C (gas; C1-C4).
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Effect of glucose ingestion in plasma markers of inflammation and oxidative stress: analysis of 16 plasma markers from oral glucose tolerance test samples of normal and diabetic patients.
Diabetes Res. Clin. Pract.
PUBLISHED: 02-11-2013
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Sixteen plasma markers of inflammation and oxidative stress were measured during OGTT in 54 subjects. Leptin, RBP4, CRP, OPN, ANG, MDC, and MCSF concentrations significantly decreased during OGTT (P<0.05). IL6, IL8, and MCP3 concentrations significantly increased during OGTT (P<0.05). These results provide evidence that glucose ingestion affects systemic inflammation and oxidative stress.
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Double hydrophilic Janus cylinders at an air-water interface.
Langmuir
PUBLISHED: 01-31-2013
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Colloidal particles spontaneously attach to the interface between two immiscible fluids to minimize the interfacial area between the two phases. The shape and wettability of particles have a strong influence on their configuration and interactions at fluid-fluid interfaces. In this study, we investigate the behavior of asymmetrically hydrophilic Janus cylinders (or double hydrophilic Janus cylinders with two different hydrophilic regions) trapped at an air-water interface. We find that these double hydrophilic Janus cylinders with aspect ratios of 0.9, 1.2, and 2.4 adopt both end-on and tilted configurations with respect to the interface. Our numerical calculations show that the coexistence of these configurations is a result of multiple energy minima present in the attachment energy profile that can be represented as a complex energy landscape. Double hydrophilic Janus cylinders with tilted orientations induce hexapolar interface deformation, which accounts for the pair interactions between the particles as well as the nondeterministic assembly behaviors of these particles at the interface.
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TRPM7 Is Essential for RANKL-Induced Osteoclastogenesis.
Korean J. Physiol. Pharmacol.
PUBLISHED: 01-20-2013
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The transient receptor potential melastatin type 7 (TRPM7) channel is a widely expressed non-selective cation channel with fusion to the C-terminal alpha kinase domain and regarded as a key regulator of whole body Mg(2+) homeostasis in mammals. However, the roles of TRPM7 during osteoclastogenesis in RAW264.7 cells and bone marrow-derived monocyte/macrophage precursor cells (BMMs) are not clear. In the present study, we investigate the roles of TRPM7 in osteoclastogenesis using methods of small interfering RNA (siRNA), RT-PCR, patch-clamp, and calcium imaging. RANKL (receptor activator of NF-?B ligand) stimulation did not affect the TRPM7 expression and TRPM7-mediated current was activated in HEK293, RAW264.7, and BMM cells by the regulation of Mg(2+). Knock-down of TRPM7 by siTRPM7 reduced intracellular Ca(2+) concentration ([Ca(2+)](i)) increases by 0 mM [Mg(2+)](e) in HEK293 cells and inhibited the generation of RANKL-induced Ca(2+) oscillations in RAW264.7 cells. Finally, knock-down of TRPM7 suppressed RANKL-mediated osteoclastogenesis such as activation and translocation of NFATc1, formation of multinucleated cells, and the bone resorptive activity, sequentially. These results suggest that TRPM7 plays an essential role in the RANKL-induced [Ca(2+)](i) oscillations that triggers the late stages of osteoclastogenesis.
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Organized Comprehensive Stroke Center is Associated with Reduced Mortality: Analysis of Consecutive Patients in a Single Hospital.
J Stroke
PUBLISHED: 01-16-2013
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Organized inpatient stroke care is one of the most effective therapies for improving patient outcomes. Many stroke centers have been established to meet this need, however, there are limited data on the effectiveness of these organized comprehensive stroke center (CSC) in the real-world setting. Our aim is to determine whether inpatient care following the establishment of CSC lowers mortality of patients with acute ischemic stroke (AIS).
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Alteration of media composition and light conditions change morphology, metabolic profile, and beauvericin biosynthesis in Cordyceps bassiana mycelium.
J. Microbiol. Biotechnol.
PUBLISHED: 01-15-2013
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Metabolic alterations of Cordyceps bassiana mycelium were investigated under the following culture medium and light conditions: dextrose agar supplemented with 0.5% yeast extract (SDAY) medium with light (SL), SDAY medium without light (SD), nut medium without light (ND), and iron-supplemented SDAY medium without light (FD). The levels of asparagine, aspartic acid, glutamic acid, glutamine, histidine, lysine, ornithine, and proline were significantly higher under SD and SL conditions. The levels of most of the alcohols, saturated fatty acids, unsaturated fatty acids, fatty acid esters, sterols, and terpenes were higher under the ND condition than in the other conditions, but beauvericin was not detectable under the ND condition. The FD condition was favorable for the enhanced production of aminomalonic acid, malic acid, mannonic acid, and erythritol. Thus, the metabolic characteristics of C. bassiana can be manipulated by varying the cultivation conditions, rendering this fungus potentially favorable as a nutraceutical and medicinal resource.
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One step formation of controllable complex emulsions: from functional particles to simultaneous encapsulation of hydrophilic and hydrophobic agents into desired position.
Adv. Mater. Weinheim
PUBLISHED: 01-06-2013
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This article presents a one-step method for generating complex emulsions that exploits the phase separation of the emulsion droplet generated in the microchannel. This approach easily produces double, triple, quadruple, and Janus emulsions with monodisperse size. These emulsions can be used as useful templates for the synthesis of new functional materials, such as microcapsules, hemispheres, Janus particles and microcarriers that are capable of simultaneously encapsulating hydrophilic and hydrophobic compounds with selective compartmentalization in a one-step process.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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