Effect of Synthesis Time and Composition on Magnetic Properties of FeCo Nanoparticles by Polyol Method.

This study investigated the effect of synthesis time and composition on magnetic properties of FeCo nanoparticles. Fe75Co25, Fe66Co34, Fe52Co48 nanoparticles were synthesized by the polyol method. The saturation magnetization of Fe75 Co25, Fe66Co34, Fe52Co48 nanoparticles was 178 emu/g, 191 emu/g and 197 emu/g, respectively. The coercivity of Fe75 Co25, Fe66Co34, Fe52Co48 was 113 Oe, 131 Oe and 89.2 Oe respectively. The synthesis time of Fe52Co48 nanoparticles was also varied (2 h and 3 h) to determine the optimal synthesis time. The saturation magnetization of Fe52Co48 synthesized for 2 h, 3 h was 243 emu/g, 202 emu/g, respectively. The coercivity of Fe52Co48 synthesized for 2 h and 3 h was 46 Oe and 111 Oe, respectively. The highest saturation magnetization and lowest coercivity was obtained using a synthesis time of 2 h. Based on these results, it was confirmed that Fe52Co48 had the highest saturation magnetization and lowest coercivity among all of the compositions tested, and optimal synthesis time was 2 h.

Safflower seed extract inhibits osteoclast differentiation by suppression of the p38 mitogen-activated protein kinase and IκB kinase activity.

Safflower seed has been reported to have a protective effect against bone loss diseases. However, the precise molecular mechanisms underlying the inhibitory effect of safflower seed in osteoclast differentiation remain unclear. In this study, we investigated the inhibitory action of safflower seed extract (SSE) on the receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclastogenesis in cultured mouse-derived bone marrow macrophages (BMMs). We found that SSE significantly inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells in BMMs without cytotoxicity. The gene expressions of nuclear factor of activated T-cells (NFATc1) and TRAP, which are genetic markers of osteoclast differentiation, were substantially decreased by SSE in a dose-dependent manner. Also, SSE diminished RANKL-mediated intracellular reactive oxygen species (ROS) generation on osteoclastogenesis in a dose-dependent manner. The SSE thereafter suppressed RANKL-induced p38 mitogen-activated protein kinase and IκBα kinase signalling activities which were activated by ROS generation for osteoclastogenesis. Additionally, SSE was found to decrease RANKL-induced actin ring formation, which is required for bone resorption activity. Taken together, our results suggest that SSE acts as a RANKL-induced osteoclastogenesis inhibitor by suppression of ROS generation. This induces a remarkable suppression of the p38 and IκBα kinase pathways, thereby suppressing the gene expression of NFATc1 in osteoclast precursors.

Serum and aqueous humor adiponectin levels correlate with diabetic retinopathy development and progression.

PURPOSE: To compare adiponectin (APN) levels in the serum and aqueous humor (AH) and evaluate their association with the development/progression of diabetic retinopathy (DR). METHODS: Diabetic patients with (group 3; n = 59) and without (group 2; n = 39) DR and age- and sex-matched normal subjects (group 1; n = 35) were compared. Duration of diabetes, body mass index, serum HbA1c, vascular endothelial growth factor (VEGF), APN, pentraxin 3 (PTX3), platelet derived growth factor (PDGF), intercellular adhesion molecule-1 (ICAM-1), and APN were measured and analyzed. RESULTS: One hundred and thirty-three participants were included. Compared to patients without diabetes, diabetic patients with DR had significantly elevated average serum APN levels (5.99±3.89 µg/ml versus 3.51±1.44 µg/ml, P = 0.002) and average AH APN levels (10.94±11.74 ng/ml versus 3.65±3.33 ng/ml, P<0.001). Serum APN was significantly correlated with AH APN (R = 0.512, P<0.001) and AH VEGF (R = 0.202, P = 0.020). The log serum APN was significantly correlated with intraocular cytokines, including log APN, log VEGF, log ICAM, log leptin, log PTX3, log PDGF, angiopoietin, C-reactive protein, and interleukins (IL)-5 and IL-10 (P<0.001, P = 0.020, P<0.001, P<0.001, P = 0.001, P<0.001, P = 0.008, P = 0.009, P<0.001, and P = 0.046, respectively). Log serum VEGF showed a significant correlation only with log AH VEGF (P = 0.001). Multivariate logistic analysis was performed to evaluate the association of DR progression and cytokine concentrations; log Serum APN and log AH APN showed good correlation with the DR progression in each model. CONCLUSIONS: AH APN levels correlated well with DR development and progression. Serum APN could be a better marker for estimating intraocular cytokines, including both intraocular APN and VEGF concentrations in clinical field, than serum VEGF in DR patients.

Thermal Conductivity and Electromagnetic Interference (EMI) Absorbing Properties of Composite Sheets Composed of Dry Processed Core-Shell Structured Fillers and Silicone Polymers.

This paper proposes dual-functional sheets (DFSs) that simultaneously have high thermal conductivity (TC) and electromagnetic interference (EMI) absorbing properties, making them suitable for use in mobile electronics. By adopting a simple but highly efficient dry process for manufacturing core-shell structured fillers (CSSFs) and formulating a close-packed filler composition, the DFSs show high performance, TC of 5.1 W m-1 K-1, and a -4 dB inter-decoupling ratio (IDR) at a 1 GHz frequency. Especially, the DFSs show a high dielectric breakdown voltage (BDV) of 3 kV mm-1, which is beneficial for application in most electronic devices. The DFSs consist of two kinds of CSSFs that are blended in accordance with the close-packing rule, Horsfield's packing model, and with polydimethylsiloxane (PDMS) polymers. The core materials are soft magnetic Fe-12.5%Cr and Fe-6.5%Si alloy powders of different sizes, and Al2O3 ceramic powders of a 1-µm diameter are used as the shell material. The high performance of the DFS is supposed to originate from the thick and stable shell layer and the maximized filler loading capability owing to the close-packed structure.

Synthesis of FeCo Alloy Nanoparticles for Electromagnetic Absorber by Polyol Method.

The correlations among magnetic properties, synthesis temperature, and composition of FeCo nanoparticles were investigated herein. Fe80Co20 alloy nanoparticles synthesized at different temperatures (383, 393, 403, 413, 428, and 443 K) showed variable compositions and aggregation degrees of the FeCo nanoparticles. Under the optimized conditions of synthesis temperature of 403 K and duration of 1 h, FeCo nanoparticles were synthesized at molar ratios of 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, and 1:9. The FeCo alloy nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, vibrating sample magnetometer, fourier transform infrared, and network analyzer. With increasing Co content, the extent of aggregation increased. The cobalt ferrite phase was detected under some conditions, and all FeCo nanoparticles showed high saturation magnetization and low coercive forces. The prepared FeCo nanoparticles exhibited high permeability at a high frequency range.

Quantitative evaluation of choriocapillaris using optical coherence tomography and optical coherence tomography angiography in patients with central serous chorioretinopathy after half-dose photodynamic therapy.

PURPOSE: To quantify the structural and perfusion changes in choriocapillaris in chronic central serous chorioretinopathy after half-dose photodynamic therapy by using spectral-domain optical coherence tomography and optical coherence tomography angiography. METHODS: This retrospective interventional case series examined the eyes of patients with central serous chorioretinopathy. Patients underwent full ophthalmic examinations, including spectral-domain optical coherence tomography and angiography, prior to and 1, 3, and 6 months after the treatment. Clinical and tomographic features of the choriocapillaris and choroidal thickness and vascular changes were evaluated by assessing flow signal voids. RESULTS: All 56 eyes of 56 patients showed complete resolution of subretinal fluid at 3 months after photodynamic therapy. The best-corrected visual acuity significantly improved at 6 months (p<0.001). The central subfield thickness, subfoveal choroidal thickness, subfoveal choroidal large vessel layer thickness, and mean total area of flow signal voids decreased significantly at 6 months (all p values < 0.001), but the subfoveal choriocapillaris layer thickness did not change significantly at 6 months (p≥0.16). Multivariate analysis revealed positive linear correlations of the central subfield thickness and subfoveal choroidal large vessel layer thickness with the mean total area of flow signal voids at 6 months (p<0.001). There was a negative linear correlation between the subfoveal choriocapillaris layer and the mean total area of flow signal voids at 6 months (p = 0.013). CONCLUSION: Half-dose photodynamic therapy improved the anatomic and functional outcomes of central serous chorioretinopathy, induced subfoveal choroidal thickness thinning, and increased choriocapillaris perfusion. In addition, the recovery of the subfoveal choriocapillaris layer thickness and improved choriocapillaris perfusion were closely associated.

Synthesis of titanate nanotube from different phases of TiO2 powders and its hydrogen absorption capacity.

Titanate nanotubes were synthesized by hydrothermal method with different NaOH concentration using various TiO2 powders (P-25, rutile, anatase, and Ni doped TiO2) at 120 degrees C for 24 hrs. At 10 M NaOH, Ni doped TiO2 powders formed the titanate nanotubes which consisted of layered structure such as A2Ti2O5.H2O, A2Ti3O7, H2TiO.H2O (A = Na and/or H) with outer and inner diameter of approximately 10 nm and 6 nm. Ni doped nanotubes absorbed a small amount of hydrogen at 6 and 10 atm, however, uptake of hydrogen was 1.2 wt% at 20 atm.

Synthesis and characterization of titanate nanotube for hydrogen storage using hydrothermal method with various alkaline treatment.

Titanate nanotubes and nanofibers were synthesized by hydrothermal method using various alkaline solutions (NaOH and KOH) in order to study the effect of synthesis condition for hydrogen storage. The microstructures of titanate nanotube and nanofibers were characterized by XRD, TEM, FE-SEM. It was found that interlayer spacing of titanate nanotubes and nanofibers depended on the alkaline solution, because some of the Ti-O-Ti bonds were broken and layered titanate nanosheet of Ti-O-A (Na+ and K+) bonds were formed. The sorption of hydrogen of the titanate nanotubes and nanofibers were studied by the conventional volumetric pressure-composition isothermal method at RT, 30 atm. The relationships between interlayer spacing, ionic radius of alkaline solution and hydrogen capacity have been discussed.

Structural characterization of titanate nanotubes for lithium storage.

Titanate nanotubes were synthesized by hydrothermal method using various TiO2 precursors as starting materials. The electrochemical properties were investigated by cyclic voltammetric methods. The microstructure and morphology of the synthesized powders were characterized by XRD, TEM. Titanate nanotubes composed of H2Ti2O5 x H2O with outer and inner diameter of approximately 10 nm and 6 nm, and the interlayer spacing was about 0.65 approximately 0.74 nm. Also, the titanate nanotubes showed a discharge capacity of 303 mAh/g and the highest cycle stability because of the open-end and rolled layers with suitable spacing. The relationships between morphology and electrochemical properties have been also discussed.

Nerve growth factor concentration and implications in photorefractive keratectomy vs laser in situ keratomileusis.

PURPOSE: To determine whether tear nerve growth factor (NGF) concentration correlates with corneal sensation and ocular surface dryness after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). DESIGN: Prospective, nonrandomized comparative clinical trial. METHODS: Seventy eyes of 35 patients and 76 eyes of 38 patients underwent PRK and LASIK procedures to correct myopia and myopic astigmatism, respectively. Total tear protein level, tear NGF concentration, tear film breakup time (BUT) and Schirmer values were measured before and 1 day, 1 week, 1 month, 3 months, and 6 months after surgery. RESULTS: The postoperative mean tear NGF/total tear protein (NGF/tP) ratio increased in both PRK and LASIK patients compared with preoperative levels (P < .0001). At 1 week and 1 month postoperatively, the NGF/tP ratio was higher in PRK than in LASIK subjects (P < .0001). Before 6 months postoperatively, the mean corneal sensation after LASIK in the ablated zone was lower than the preoperative sensation (P < .0001), but this was not the case in PRK subjects. Mean BUT and Schirmer values were significantly lower in LASIK-treated eyes compared with PRK-treated eyes up to 6 months postoperatively (P < .0001). The early postoperative tear NGF/tP ratio correlated with the postoperative 6-month value of corneal sensation, BUT, and Schirmer values. CONCLUSIONS: The difference in the postoperative corneal sensation and ocular surface dryness between PRK-treated and LASIK-treated eyes might be related to the difference in the early postoperative levels of NGF, which is a potent nerve growth stimulator.

Epithelial healing and clinical outcomes in excimer laser photorefractive surgery following three epithelial removal techniques: mechanical, alcohol, and excimer laser.

PURPOSE: To evaluate epithelial healing, postoperative pain, and visual and refractive outcomes after photorefractive keratectomy (PRK) using three epithelial removal techniques. DESIGN: Prospective, nonrandomized, comparative trial. SETTING: Department of Ophthalmology, Yonsei University College of Medicine and Balgensesang Ophthalmology Clinic, Seoul, Korea. INTERVENTIONS: For the PRK procedure, the corneal epithelium was removed in one of three ways: mechanically (conventional PRK [PRK]) in 88 eyes of 44 patients; using excimer laser (transepithelial PRK [tPRK]) in 106 eyes of 53 patients; or using 20% diluted alcohol, laser-assisted subepithelial keratomileusis (LASEK) in 106 eyes of 53 patients. MAIN OUTCOME MEASURES: Epithelial healing, postoperative pain, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and remaining refractive error. RESULTS: The mean postoperative pain scores were 4.84 +/- 1.45 for PRK, 4.71 +/- 1.62 for tPRK, and 4.63 +/- 1.52 for LASEK (P = .125). The mean epithelial healing rates were 12.3 +/- 4.6 for PRK, 15.2 +/- 4.9 for tPRK, and 18.1 +/- 5.2 mm2/day for LASEK (P < .001). The postoperative 6-month remaining mean spherical equivalents (diopters) were -0.46 +/- 1.01 for PRK, 0.18 +/- 0.91 for tPRK, and -0.82 +/- 1.18 for LASEK (P = .01). The LASEK group showed less favorable UCVA than other groups. There was no significant difference in BSCVA between the groups. CONCLUSIONS: Postoperative pain, subepithelial opacity and BSCVA were similar regardless of the epithelial removal procedure. A faster epithelial healing rate did not result in better visual or refractive outcomes. Using the same nomogram, tPRK resulted in a slight overcorrection, and LASEK resulted in a slight undercorrection.

Clinical trial of herbal formula on weight loss in obese Korean children.

A traditional Korean herbal formula (KH), which is based on Taeumjowi-tang, is currently the most widely used herbal formula in Korea. In this study, KH was administered to obese children for 30 days, and was found to be clinically safe and effective. The subjects were children admitted to hospital to be treated for obesity with relative body weights (%RBW) of 20% or more. Originally, there were 31 subjects, but nine dropped out during the experiment. There were eight girls and 14 boys, whose average age was 11.00 +/- 2.62 years, average weight was 53.37 +/- 17.29 kg, and average period (30-day amount) of KH dosage was 51.18 +/- 22.58 days. The short-term effects of KH on obese children were the reduction of their BMI from 24.34 +/- 3.10 to 23.26 +/- 3.00 kg/m2, of %RBW from 34.41 +/- 10.90 to 25.94 +/- 11.18% (p < 0.01), of body fat mass from 17.99 +/- 5.37 to 16.50 +/- 4.82 kg, and of body fat from 34.16 +/- 3.75 to 32.08 +/- 3.15% (p < 0.01). Concerning anthropometrical measurements, abdominal skin-fold decreased from 26.16 +/- 9.08 to 22.90 +/- 8.35 mm, as did subscapular skin-fold from 20.86 +/- 5.20 to 18.46 +/- 5.31 mm (p < 0.01). In terms of serum lipid levels, which are indices of heart disease, their total cholesterol decreased from 195.38 +/- 31.39 to 183.25 +/- 33.27 mg/dl, the arteriosclerosis index from 4.100 +/- 0.81 to 3.84 +/- 0.64 mg/dl (p < 0.05), and serum leptin level from 14.91 +/- 6.59 to 12.24 +/- 4.98 ng/ml (p < 0.01). Concerning the safety of KH, there were no significant changes in the subjects' livers, hearts, or kidneys. Nor were there any short-term signs of clinically serious side effects or withdrawal symptoms observed. The short-term effects of KH on obese children are weight loss and a decrease in obesity.

Effect of Korean red ginseng on cold hypersensitivity in the hands and feet: study protocol for a randomized controlled trial.

BACKGROUND: Cold hypersensitivity in the hands and feet (CHHF) is one of the most common complaints among Asians, especially in women. Korean red ginseng (KRG), which is a steamed form of Panax ginseng, has vasodilating action in the peripheral vessels and increases blood flow under cold stress. However, few studies have evaluated the effect of KRG on cold hypersensitivity. METHODS/DESIGN: This trial is a randomized, double-blind, placebo-controlled trial in 80 CHHF patients. The trial will be implemented at Kyung Hee University Hospital at Gangdong in Seoul, Korea. The participants will take KRG or a placebo for eight weeks, after which they will be followed-up for four weeks. During the administration period, six capsules of 500 mg KRG or placebo will be provided twice a day. The primary outcome is change of skin temperature in the hands between baseline and after treatment. The secondary outcomes include the visual analogue scale scores of cold hypersensitivity in the hands, change of skin temperature and the VAS scores of cold hypersensitivity in the feet, the recovery rate of the skin temperature by the cold stress test of the hands, the distal-dorsal difference of the hands, power variables of heart rate variability, and the 36-item short form health survey. DISCUSSION: This study is the first trial to evaluate the efficacy of KRG on CHHF by using infrared thermography. Our study will provide basic evidence regarding CHHF. TRIAL REGISTRATION: CliniacalTrials.gov NCT01664156.

Dangguijakyak-san, a medicinal herbal formula, protects dopaminergic neurons from 6-hydroxydopamine-induced neurotoxicity.

AIM OF THE STUDY: Dangguijakyak-san (DJS) is a multi-herbal formula that has long been widely used in traditional Oriental medicine to treat gynecologic disorders, including neurological symptoms. Recent clinical and experimental studies have reported aging and anti-neurodegenerative effects of DJS. In this study, we evaluated the neuroprotective effects of DJS on dopaminergic (DA) neurons damaged by 6-hydroxydopamine (6-OHDA). MATERIALS AND METHODS: To evaluate the protective effects of DJS, we analyzed viability in SH-SY5Y neuroblastoma cells and tyrosine hydroxylase (TH) staining in primary DA cells. To explore the possible mechanism(s) of neuroprotection, we assessed anti-oxidant activity by measuring reactive oxygen species (ROS) and glutathione (GSH) levels. To determine mitochondria-mediated apoptotic activity, we examined mitochondrial membrane potential, cytochrome c release, and caspase-3 activation. RESULTS: DJS at 0.05-5 µg/mL significantly protected SH-SY5Y cells from 6-OHDA toxicity, dose-dependently, and attenuated 6-OHDA damage in primary DA cells. DJS reduced 6-OHDA-induced intracellular ROS production and GSH depletion and inhibited mitochondrial membrane instability, cytosolic cytochrome c release, and caspase-3 activation. CONCLUSIONS: These results demonstrate that DJS has neuroprotective effects in DA neurons against 6-OHDA-induced toxicity through anti-oxidant and anti-mitochondrial-mediated apoptotic activities.

Protective effect of Cyperi rhizoma against 6-hydroxydopamine-induced neuronal damage.

Cyperi rhizoma, the rhizome of Cyperus rotundus L. (Family Cyperaceae), is a well-known functional food and traditional herbal medicine in Korea. It has been reported that Cyperi rhizoma has antioxidant and free radical scavenging activities that play a major role in protection of neurodegenerative disorders, such as Parkinson's disease (PD). In the present study, the neuroprotective effects of a water extract of Cyperi rhizoma (CRE) against 6-hydroxydopamine (6-OHDA)-induced neuronal damage were evaluated in an experimental model of PD. In PC12 cells, CRE showed a significant protective effect on cell viability at 50 and 100 microg/mL. CRE inhibited generation of reactive oxygen species and nitric oxide, reduction of mitochondrial membrane potential, and caspase-3 activity, which were induced by 6-OHDA. CRE also showed a significant protective effect against damage to dopaminergic neurons in primary mesencephalic culture. These results suggest that CRE has neuroprotective effects against 6-OHDA-induced toxicity through antioxidant and anti-apoptotic activities in an in vitro PD model.

Therapeutic effects of Chiljehyangbuhwan on primary dysmenorrhea: a randomized, double blind, placebo-controlled study.

OBJECTIVE: This clinical study was conducted to investigate the efficacy and safety of an oriental herbal medicine native to Korea, Chiljehyangbuhwan, in treating primary dysmenorrhea. DESIGN AND SETTING: A total of 100 primary dysmenorrhea patients who visited Kyung Hee University Korean Oriental Medicine Hospital between July 19 2004 and August 27 2004 were recruited. Secondary or drug-related dysmenorrhea was screened out through interviews and examination. The patients were grouped by fixed blocked randomization and administered either Chiljehyangbuhwan or placebo for one menstrual period in a double blind model. Visual Analogue Scale (VAS), Verbal Rating Scale (VRS), and Multidimensional Verbal Rating Scale (MVRS) were used to evaluate dysmenorrhea severity. A total of 71 patients who passed the screening test and remained to the last were divided into either placebo or Chiljehyangbuhwan group, and each were further split into smaller subsets (indication, non-indication, and unspecified group) according to Korean Oriental medical diagnosis. RESULTS: In the non-indication group, the placebo and Chiljehyangbuhwan group did not show significant difference in VAS, VRS, and MVRS scores before medication (1st VAS, 1st VRS, 1st MVRS), after medication (2nd VAS, 2nd VRS, 2nd MVRS), and in changes in scores before and after (DeltaVAS, DeltaVRS, DeltaMVRS). In the indication group, the placebo and Chiljehyangbuhwan group showed significant difference in change in VAS and MVRS scores (DeltaVAS and DeltaMVRS). No evidence of toxicity could be found, and no serious adverse reactions to Chiljehyangbuhwan were reported. CONCLUSION: The results suggest that Chiljehyangbuhwan is effective and safe in treating primary dysmenorrhea when prescribed appropriately under Korean Oriental medical diagnosis.