Search

• Highly monodisperse starch nano/microparticles synthesized by self-assembly process. • The factors affecting the nucleation and growth kinetics were investigated. • Steric stabilization plays a key role in the formation of monodisperse particles. • The size of starch particles could be controlled by the rate of debranching reaction. • Fully applicable for the synthesis of a food-grade drug delivery system. Here, we report a sustainable approach for the synthesis of starch-based microparticles with well-defined shape and size through molecular self-assembly of short-chain glucan (SCG) obtained enzymatically from waxy maize starch. We employed chitosan as a steric stabilizer to modulate the nucleation process, which significantly reduced undesirable aggregations during the nucleation and growth phases, resulting in the production of highly monodisperse microparticles. The size of chitosan-assisted starch microparticles (CS-SMPs) was effectively controlled by the concentration of debranching enzyme as well as by debranching time, of which the factors influencing the final size were investigated. By modulating the rate and time of debranching reaction in combination with the steric stabilizing effect of chitosan, we were able to prepare highly monodisperse CS-SMPs from 200 nm to 5 μm with a production yield of over 70% from natural starch. Furthermore, the potential of CS-SMPs as a carrier system for oral delivery of bioactive compounds were demonstrated using model guest molecules. [ABSTRACT FROM AUTHOR]

The recyclable silicone-based thermoset was successfully synthesized by making use of a Diels-Alder (DA) adduct as a cross-linker. The incorporation of the furan-tethered diol 1 into the polymer backbones realized the crosslinking of polymers via the DA reaction. The thermosetting polymer was dissolved in DMF after the retro DA reaction which was monitored by 1 H NMR spectroscopy. Due to the retro DA reaction, polymer showed the mendable behavior when it was scratched followed by being heated. This polymer was mixed with alumina powders to fabricate the thermal pad. The thermal resistance of this pad was measured to be 0.48 K/W by a thermal transient test. The thermosetting composite was recycled via the retro DA reaction. The thermal resistance of the recycled one was similar to that of the original one. [ABSTRACT FROM AUTHOR]

CF 4 , which is widely used in the production of semiconductors and aluminum, has a very high global warming potential and extremely long atmospheric lifetime. Adsorption is an alternative technique to the energy-consuming conventional CF 4 combustion disposal method, and the development of appropriate adsorbents is important for a competent CF 4 adsorption process. Here, microporous carbons are synthesized for new CF 4 adsorbents by the selective etching of titanium carbide using chlorine gas at high temperatures (800, 900, and 1000 °C). Additionally, post-treatment with H 2 eliminates any unreacted chlorine. Interestingly, the CF 4 adsorption capacity has a linear relation with the micropore volume for pores less than 0.9 nm. The titanium carbide-based microporous carbon chlorinated at 800 °C and post-treated with H 2 has the highest CF 4 adsorption capacity of 2.96 mol kg −1 at 25 °C and 1 atm, which is the highest reported value to date. Besides the high CF 4 adsorption capacity, the prepared microporous carbon shows a high selectivity for CF 4 over N 2 at low CF 4 partial pressures and an excellent cyclic stability. [ABSTRACT FROM AUTHOR]

Flavonoid myricetin has been shown to exhibit anti-inflammatory and anti-oxidant effects. Nevertheless, the effect of myricetin on the TNF-α-stimulated production of inflammatory mediators in keratinocytes has not been studied. Using human keratinocytes, we examined the effect of myricetin on the TNF-α-stimulated production of inflammatory mediators in relation to the Akt, mTOR and NF-κB pathways, which regulate the transcription genes involved in immune and inflammatory responses. TNF-α stimulated production of the inflammatory mediators and reactive oxygen species in keratinocytes, and activation of the Akt, mTOR and NF-κB pathways in HaCaT cells and primary keratinocytes. Myricetin, Akt inhibitor, Bay 11-7085 (an inhibitor of NF-κB activation), rapamycin (mTOR inhibitor) and N -acetylcysteine attenuated TNF-α-induced activation of Akt, mTOR and NF-κB. Myricetin and N -acetylcysteine attenuated the TNF-α-stimulated production of cytokines and chemokines, and production of reactive oxygen species in keratinocytes. The results show that myricetin may reduce TNF-α-stimulated inflammatory mediator production in keratinocytes by suppressing the activation of the Akt, mTOR and NF-κB pathways. The effect of myricetin appears to be associated with inhibition of the production of reactive oxygen species. Further, myricetin appears to attenuate the proinflammatory mediator-induced inflammatory skin diseases. [ABSTRACT FROM AUTHOR]

Dysfunction of the proteasome system has been suggested to be implicated in neuronal degeneration. Modulation of K ATP channels appears to affect the viability of neuronal cells exposed to toxic insults. However, the effect of K ATP channel blockers on the neuronal cell death mediated by proteasome inhibition has not been studied. The present study investigated the effect of K ATP channel blockers on proteasome inhibitor-induced apoptosis in differentiated PC12 cells and SH-SY5Y cells. 5-Hydroxydecanoate (a selective K ATP channel blocker) and glibenclamide (a cell surface and mitochondrial K ATP channel inhibitor) reduced the proteasome inhibitor-induced apoptosis. Addition of the K ATP channel blockers attenuated the proteasome inhibitor-induced changes in the levels of apoptosis-related proteins, the loss of the mitochondrial transmembrane potential, the increase in the formation of reactive oxygen species and the depletion of glutathione in both cell lines. The results show that K ATP channel blockers may attenuate proteasome inhibitor-induced apoptosis in PC12 cells by suppressing activation of the mitochondrial pathway and of the caspase-8- and Bid-dependent pathways. The preventive effect appears to be associated with the inhibition of the formation of reactive oxygen species and the depletion of glutathione. K ATP channel blockade appears to prevent proteasome inhibition-induced neuronal cell death. [ABSTRACT FROM AUTHOR]

Cholesterol oxidation products are suggested to be involved in neuronal degeneration. Apocynin has demonstrated to have anti-inflammatory and anti-oxidant effects. We assessed the effect of apocynin on the cholesterol oxidation product-induced programmed cell death in neuronal cells using differentiated PC12 cells in relation to NF-κB-mediated cell death process. 7-Ketocholesterol and 25-hydroxycholesterol decreased the levels of Bid and Bcl-2, increased the levels of Bax and p53, and induced loss of the mitochondrial transmembrane potential, release of cytochrome c and activation of caspases (-8, -9 and -3). 7-Ketocholesterol caused an increase in the levels of cytosolic and nuclear NF-κB p65, cytosolic NF-κB p50 and cytosolic phospho-IκB-α, which was inhibited by the addition of 0.5 μM Bay11-7085 (an inhibitor of NF-κB activation). Apocynin attenuated the cholesterol oxidation product-induced changes in the programmed cell death-related protein levels, NF-κB activation, production of reactive oxygen species, and depletion of GSH. The results show that apocynin appears to attenuate the cholesterol oxidation product-induced programmed cell death in PC12 cells by suppressing the activation of the mitochondrial pathway and the caspase-8- and Bid-dependent pathways that are mediated by NF-κB activation. The preventive effect appears to be associated with the inhibitory effect on the production of reactive oxygen species and depletion of GSH. [ABSTRACT FROM AUTHOR]

The extract of from the barks of Ilex Rotunda Thunb has demonstrated anti-inflammatory and anti-oxidant effects. Nevertheless, the effect of rotundarpene (4-caffeoyl-3-methyl-but-2-ene-1,4-diol) on the neuronal cell death induced by cholesterol oxidation products is unclear. We assessed the preventive effect of rotundarpene on the cholesterol oxidation product-induced apoptosis in neuronal cells using differentiated PC12 cells. 7-Ketocholesterol and 25-hydroxycholesterol induced a decrease in Bid, Bcl-2, Bcl-xL and survivin protein levels, increase in Bax levels, loss of the mitochondrial transmembrane potential, cytochrome c release, activation of caspases (-8, -9 and -3), cleavage of PARP-1 and an increase in the tumor suppressor p53 levels. Rotundarpene attenuated the cholesterol oxidation product-induced changes in the apoptosis-related protein levels, formation of reactive oxygen species, depletion of GSH, nuclear damage and cell death. The results show that rotundarpene may attenuate the cholesterol oxidation product-induced apoptosis in PC12 cells by suppressing the activation of the mitochondrial pathway and the caspase-8- and Bid-dependent pathways. The preventive effect appears to be attributed to its inhibitory effect on the formation of reactive oxygen species and depletion of GSH. Rotundarpene appears to attenuate cholesterol-oxidation product-mediated neuronal degeneration. [ABSTRACT FROM AUTHOR]

Intimate partner violence (IPV) is often studied as a problem that predominantly affects younger women. However, studies show that older women are also frequently victims of abuse even though the physical effects of abuse are harder to detect. In this study, we mined the electronic health records (EHR) available through IBM Explorys to identify health correlates of IPV that are specific to older women. Our analyses suggested that diagnostic terms that are co-morbid with IPV in older women are dominated by substance abuse and associated toxicities. When we considered differential co-morbidity, i.e., terms that are significantly more associated with IPV in older women compared to younger women, we identified terms spanning mental health issues, musculoskeletal issues, neoplasms, and disorders of various organ systems including skin, ears, nose and throat. Our findings provide pointers for further investigation in understanding the health effects of IPV among older women, as well as potential markers that can be used for screening IPV. [ABSTRACT FROM AUTHOR]

Objectives: In this study we investigated the effects of native inulin on formula-fed babies. The influence of inulin on the microbial composition, pH, consistency and amount of faeces, and on frequency of defecation was assessed.Methods: In this study a daily dosage of 0.25 g/kg/d was used: 3 weeks of inulin consumption were inulin followed by 3 weeks without or vice versa. The study group consisted of 14 babies with an average age of 12.6 weeks (+/-6.4 weeks) and the average intake of inulin was 1.5 (+/-0.3) g/d.Results: The consumption of inulin increased the content of Bifidobacterium and Lactobacillus in the faeces of formula-fed babies, without affecting the number of Bacteroides or the total anaerobic count. With inulin a trend for stools becoming softer and the amount of faeces increased significantly. Frequency of defecation was not affected by the consumption of inulin. No adverse effects were reported during the periods of inulin consumption.Conclusions: We conclude that with native inulin a prebiotic effect can be observed in formula-fed babies. Inulin may therefore be a useful ingredient in the formulation of baby formula to enhance the nutritional properties. [ABSTRACT FROM AUTHOR]

(a, b, e, f) H1299 cells were treated with the indicated concentrations of metformin or phenformin for 24 h. (c, d) H1299 cells were transfected with control or ATF4 siRNA for 12 h and were then treated with 10 mM metformin for 24 h. (a-d) H1299 cells were transfected with control, AMPK , ATF4, REDD1, or Sestrin2 siRNA for 12 h and then treated with 10 mM metformin for 24 h. (a) H1299 cells were treated with the indicated concentrations of metformin or phenformin for 24 h. (b) H1299 cells were transfected with control or AMPK siRNA for 12 h and were then treated with 10 mM metformin for 24 h. (a, b) Data are representative of two independent experiments. [Extracted from the article]

Background: Although the major anticancer effect of metformin involves AMPK-dependent or AMPK-independent mTORC1 inhibition, the mechanisms of action are still not fully understood.Methods: To investigate the molecular mechanisms underlying the effect of metformin on the mTORC1 inhibition, MTT assay, RT-PCR, and western blot analysis were performed.Results: Metformin induced the expression of ATF4, REDD1, and Sestrin2 concomitant with its inhibition of mTORC1 activity. Treatment with REDD1 or Sestrin2 siRNA reversed the mTORC1 inhibition induced by metformin, indicating that REDD1 and Sestrin2 are important for the inhibition of mTORC1 triggered by metformin treatment. Moreover, REDD1- and Sestrin2-mediated mTORC1 inhibition in response to metformin was independent of AMPK activation. Additionally, lapatinib enhances cell sensitivity to metformin, and knockdown of REDD1 and Sestrin2 decreased cell sensitivity to metformin and lapatinib.Conclusions: ATF4-induced REDD1 and Sestrin2 expression in response to metformin plays an important role in mTORC1 inhibition independent of AMPK activation, and this signalling pathway could have therapeutic value. [ABSTRACT FROM AUTHOR]

Mechanistic target of rapamycin complex 1 (mTORC1) integrates various environmental signals to regulate cell growth and metabolism. mTORC1 activity is sensitive to changes in amino acid levels. Here, we investigated the effect of lysine on mTORC1 activity in non-small cell lung cancer (NSCLC) cells. Lysine deprivation suppressed mTORC1 activity and lysine replenishment restored the decreased mTORC1 activity in lysine-deprived cells. Supplementing growth factors, such as insulin growth factor-1 or insulin restored the decreased mTORC1 activity in serum-deprived cells. However, in serum/lysine-deprived cells, supplementing growth factors was not sufficient to restore mTORC1 activity, suggesting that growth factors could not activate mTORC1 efficiently in the absence of lysine. General control nonderepressible 2 and AMP-activated protein kinase were involved in lysine deprivation-mediated inhibition of mTORC1. Taken together, these results suggest that lysine might play role in the regulation of mTORC1 activation in NSCLC cells. • Lysine deprivation inhibits mTORC1 activity. • Lysine replenishment restores the decreased mTORC1 activity by lysine deprivation. • Lysine is necessary for growth factor-induced mTORC1 activation. • GCN2 and AMPK are involved in lysine deprivation-mediated inhibition of mTORC1. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Well-defined starch microparticles (SMPs) were synthesized from waxy maize starch. • Debranching of amylopectin followed by self-assembly led to the formation of SMPs. • Nucleation and growth kinetics of SMPs were investigated. • The ratio of short-chain glucan is the key to determine the size of SMPs. • Their potential as an effective immunomagnetic materials was demonstrated. Abstract Starch microparticles (SMPs) of well-defined size and morphology were synthesized through pullulanase-mediated debranching of waxy maize starch followed by spontaneous re-assembly of the resulting short-chain glucan molecules in aqueous solution. Enzymatic debranching of amylopectins from native starch generated two major fractions corresponding to a smaller glucan and partially digested larger amylopectin molecules. The ratio of short-chain glucan (SCG) over partially digested amylopectin (PDAp) turned out to be the deterministic factors for the size and crystallinity of SMPs, of which the ratio could be controlled by the concentration of debranching enzyme. The PDAp fraction was closely associated with the creation of nuclei, determining the growth kinetics of SMPs which led to the formation of SMPs with a diameter ranging from 0.52.5 μm. In addition, we demonstrated that iron oxide nanoparticles (IONPs) were successfully incorporated into the starch microstructure by introducing them during the self-assembly reaction, conferring desired functionality onto the final SMPs. The incorporated IONPs rendered the SMPs an excellent magnetic sensitivity, which were successfully applied for the separation and concentration of target bacteria upon conjugation of specific antibody on the surface of SMPs. The simple processes and biocompatible nature of starch would make this approach attractive for many applications in the area of food, medicine and other related materials sciences. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate clinical manifestations, age distribution and risk factors of adverse drug reactions ( ADRs) of statins. Korean Adverse Event Reporting System ( KAERS) database records (July 2009-June 2014) on statin-treated adults were used. ADRs classified as 'certain', 'probable' and 'possible' based on the WHO-Uppsala Monitoring Centre criteria were analysed. The frequency of ADRs was compared between adults (18-64 years) and older people (age ≥65 years) groups. In total, 2161 ADRs from 1690 patients (579, 34.3% older people) were included for analysis. Mean patient age and ADRs per patient were 60.46 ± 12.72 years and 1.28, respectively. ADRs were reported with atorvastatin (48.4%), rosuvastatin (23.0%), pitavastatin (10.4%) and simvastatin (9.1%). The frequent ADRs were gastrointestinal (421 events, 19.5%), musculoskeletal (331, 15.3%), skin (312, 14.4%) and hepatobiliary disorders (286, 13.2%). Skin disorders were significantly more frequent in adults compared to those in older patients (16.3% versus 12.4%, p = 0.021). Common clinical symptoms were myalgia (263 events, 12.2%), dyspepsia (133, 6.2%) and pruritus (103, 4.8%). Myalgia was more frequently reported in adults (12.7% versus 9.5%, p = 0.039) and dizziness was more frequent in older people (3.4% versus 5.8%, p = 0.015). According to KAERS data, leading statin ADRs were gastrointestinal and musculoskeletal disorders. Myalgia and dyspepsia were the common clinical symptoms. [ABSTRACT FROM AUTHOR]

Abstract: We developed a series of micro-size hexagon-faced plate and rods from Mn(III)-porphyrin and In(III) whose lengths were modulated by water. Regardless of a wide range of length distribution, they are isostructural. In addition, the heterogeneous olefin oxidation was performed. [Copyright &y& Elsevier]

Abstract: The physiologic consequences of using white rice or mixed rice were evaluated in overweight Korean women (body mass index ≥25kg/m2) over a period of 6 weeks. Forty women between 20 and 35 years of age were randomly divided into 2 groups who consumed 1 of 2 low-energy meal replacements containing either white rice (WR group) or mixture of brown rice and black rice (BRBL group). The subjects were not allowed to have any food other than the low-energy meal replacement 3 times a day and snacks provided by the researcher. The changes in anthropometric indices and blood parameters such as lipid levels and antioxidant activities were measured every 3 weeks during the dietary intervention. The subjects showed a significant reduction in weight, body mass index, and body fat (%) during the experimental period, with the BRBL group exhibiting levels of all 3 parameters significantly lower than those of the WR group (P < .05). The levels of total cholesterol and triacylglycerols decreased gradually and significantly after intervention in both groups, with no significant difference between groups. High-density lipoprotein cholesterol was significantly elevated in the BRBL group but not in the WR group. Superoxide dismutase activity was not affected by dietary intervention, but glutathione peroxidase activity in the BRBL group was higher than in the WR group, and the level of thiobarbituric acid–reactive substance was lower in the BRBL group compared to the WR group. In conclusion, meal replacement with mixed rice was superior to replacement with white rice in weight control, improving antioxidant enzyme activity, and as such, should be recommended for diet therapy in obese women. [Copyright &y& Elsevier]

Amylose microparticles can be produced by self-assembly of amylose molecules through an amylosucrase-mediated synthesis. Here we investigated the role of short-chain fatty acids in the formation of amylose microparticles and the fate of these fatty acids at the end of the reaction. The rate of self-assembly and production yields of amylose microparticles were significantly enhanced in the presence of fatty acids. The effect was dependent on the length of the fatty acid carbon tail; butanoic acid (C4) was the most effective, followed by hexanoic acid (C6) and octanoic acid (C8). The amylose microparticles were investigated by carrying out SEM, XRD, Raman, NMR, FT-IR and DSC analysis. The size, morphology and crystal structure of the resulting amylose microparticles were comparable with those of amylose microparticles produced without fatty acids. The results indicated the carboxyl group of the fatty acid to be responsible for promoting the self-assembly of amylose chains to form microparticles. The fatty acids were eventually removed from the microstructure through the tight association of amylose double helices to form the amylose microparticles. [ABSTRACT FROM AUTHOR]