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Abstract: A self-assembled nanoparticle was prepared using a hydrophobically modified glycol chitosan for gene delivery. A primary amine of glycol chitosan was modified with 5β-cholanic acid to prepare a hydrophobically modified glycol chitosan (HGC). The modified chitosan spontaneously formed DNA nanoparticles by a hydrophobic interaction between HGC and hydrophobized DNA. As the HGC content increased, the encapsulation efficiencies of DNA increased while the size of HGC nanoparticles decreased. Upon increasing HGC contents, HGC nanoparticle became less cytotoxic. The increased HGC contents also facilitated endocytic uptakes of HGC nanoparticles by COS-1 cells, which were confirmed by a confocal microscopy. The HGC nanoparticles showed increasing in vitro transfection efficiencies in the presence serum. In vivo results also showed that the HGC nanoparticles had superior transfection efficiencies to naked DNA and a commercialized transfection agent. The HGC nanoparticles composed of hydrophobized DNA and hydrophobically modified glycol chitosan played a significant role in enhancing transfection efficiencies in vitro as well as in vivo. [Copyright &y& Elsevier]

Molybdenum disilicide was produced from elemental powder compacts of molybdenum and silicon by self-propagating high-temperature synthesis. The effects of the reactant ratio, particle size of silicon, and density of the compact were investigated in a high-pressure microreactor. In order to get the relationships among them, the atomic ratio of silicon to molybdenum (Si/Mo) was changed from the values of 1.0 to 2.6 with steps of 0.2. Stable combustion was observed for values of atomic ratio of silicon to molybdenum of 1.8, 2.0, and 2.2. The SHS-produced material consisted of uniform and single-phased molybdenum disilicide (MoSi 2 ) for the atomic ratio of silicon to molybdenum of 2.0. In the meantime unstable combustion such as oscillatory and spinning combustion was detected for values of atomic ratio of silicon to molybdenum beyond the limits of stable combustion. The SHS-produced material under unstable combustion includes impurities of Mo 5 Si 3 , unreacted Mo and Si resulting from the layered structure which gives a lower degree of reaction and poor electrical properties of MoSi 2 heating element. A significant amount of unreacted molybdenum (≈17%) was found for the atomic ratio of silicon to molybdenum of 1.0. This may result from the spinning combustion as well as from the low combustion temperature below the melting point of silicon (≈1414 °C). The value of criterion α suggested by Shkadinskii et al. to differentiate stable combustion from unstable one, is found to be 0.74 for the production of molybdenum disilicide by self-propagating high-temperature synthesis. Stable combustion was observed for α ≥0.74 to give uniform products while unstable combustion was detected for α <0.74 to result in non-uniform and multi-phased products. This critical value should be useful for the industrial production of uniform molybdenum disilicide by self-propagating high-temperature synthesis. [ABSTRACT FROM AUTHOR]

Abstract: Fungal bioaerosols, which are major constituents of ambient airborne microorganisms, are well known for their adverse health effects. However, thus far, the effective control of fungal bioaerosols has rarely been studied. A major reason for this is a lack of stable and reliable methods of generating fungal bioaerosols that can simulate real environmental dispersal. As a first step towards developing an efficient means of controlling fungal bioaerosols, we designed and evaluated a new fungal bioaerosol generator. The multi-orifice air jets and the rotating substrate inside the generator were used to uniformly scan a fungal culture Petri plate and to maintain uniformity of the production rate of fungal bioaerosols. We conducted the experimental tests on Aspergillus versicolor and Cladosporium cladosporioides. The particle size distribution and the total particle number concentration of generated fungal bioaerosols were measured using a particle size distribution analyzer and a condensation particle counter. The effects of the air flow rate and the rotating speed of the substrate on the generation of fungal bioaerosols were investigated. The results demonstrate that the fungal bioaerosol generator can produce mono-dispersed fungal bioaerosols under various experimental conditions and that it is possible to control the rates of production of fungal bioaerosols by adjusting the flow rate through the fungal generator and the rotating speed of the substrate. [Copyright &y& Elsevier]

• Functional connectivity (FC) of firefighters with low sleep quality was explored. • Poor sleepers had weaker FC centred on attentional network seeds. • Sleep duration was associated with FC centred on the ventral frontal cortex. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Historical records reveal that in traditional medicine, a disease similar to diabetes was treated with ginseng. Korean red ginseng has been considered beneficial as a dietary supplement for its anti-diabetic potential. Aim: This study was designed to investigate the prophylactic potential of Korean red ginseng (KRG) extract (Panax ginseng C.A. Meyer Radix Rubra) in a well-established mouse model of Type 1 diabetes (T1D). Materials and methods: The prophylactic effect of KRG extract was evaluated in mice fed with KRG extract for two weeks prior to induction of diabetes by streptozotocin (STZ) administration. Glucose levels and glucose challenge test results of KRG-treated diabetic mice were compared to those of untreated diabetic mice and healthy control mice. Examination of the immune compartments in lymphoid organs and immunohistochemical staining of pancreas for islet cell morphology and insulin producing beta cells were performed. Results: KRG extract significantly lowered blood glucose levels to an average of 250mg/dl from 350mg/dl and improved glucose challenge testing when applied as prophylaxis. Histological findings indicated that KRG extract protected against STZ-induced destruction of pancreatic tissue and restored insulin secretion. Strikingly, this effect was accompanied by restoration of lymphocytes in secondary lymphoid organs, suggesting that KRG extract facilitated immune homeostasis. Conclusion: This is the first report to demonstrate the prophylactic function of KRG extract in ameliorating the hyperglycemia of T1D. Immune compartments of diabetic mice were found to be preserved in KRG-treated mice suggesting that Korean red ginseng may benefit T1D patients, not only for its hypoglycemic but also for its immunomodulatory effects. [Copyright &y& Elsevier]

Background: Acute kidney injury (AKI) is a serious complication after coronary artery bypass grafting and is closely associated with high mortality. The objective of the present study was to identify the incidence and risk factors for AKI after off-pump coronary artery bypass grafting (OPCAB) and to construct a risk model for prediction of AKI after OPCAB. Methods: We retrospectively studied 448 adult patients who underwent isolated OPCAB between April 2006 and July 2007. AKI was defined as an increase in serum creatinine of 0.3 mg//dL or 50%% within 48 h after surgery. Multivariate analysis was used to evaluate risk factors for AKI after OPCAB and a risk model was developed with a weighted score based on the odds ratio. Results: The incidence of AKI was 7.6%% ( n == 34). Most patients (97%%) had mild AKI. Independent preoperative risk factors of postoperative AKI were identified as high systolic blood pressure, decreased glomerular filtration rate, and coronary angiography (CAG) less than 7 days prior to OPCAB. The incidence of AKI across each increasing score level increased from 2.2%% to 60%%. Conclusion: AKI after OPCAB was common. High systolic blood pressure, renal dysfunction, and CAG less than 7 days prior to cardiac surgery were associated with AKI after OPCAB. Our risk model may provide information to clinicians and patients about the risk of postoperative AKI. [ABSTRACT FROM AUTHOR]