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In this article, a fully integrated dual-band gallium nitride (GaN) Doherty power amplifier (DPA) based on multi-resonant circuits (MRCs) is presented. A lumped T-type network in combination with the output capacitances of the main and auxiliary transistors is able to realize the quarter-wavelength transformer (QWT) in DPA, and its component values are totally decided by the operating frequency, given a certain characteristic impedance. MRCs are proposed to exhibit the required component values at two different frequencies. By replacing each component in the T-type network with an MRC, a dual-band QWT can be achieved. An integrated dual-band DPA is implemented in a commercial 0.25-μm GaN-HEMT process to validate the proposed method. The fabricated DPA shows a saturated output power of 43.8-44.7/44.4-44.8 dBm, a 6-dB back-off drain efficiency (DE) of 41%-46%/41.5%-47%, and a saturated DE of 49%-52%/56%-59% in 3.35-3.6/4.8-5.2 GHz, with a compact size of 2.8 x 3.5 mm². Applying a 100-MHz OFDM signal with a 7.8-dB peak-to-average power ratio (PAPR), an average efficiency of 37%/40% and an average power of 37/37 dBm are measured at 3.5/5.0 GHz, and the adjacent channel power ratio (ACPR) is better than -49 dBc after digital predistortion (DPD). To the best of our knowledge, the proposed DPA is the first demonstration of fully integrated dual-band GaN DPAs.

A series of covalent organic frameworks substituted with azo groups (AzoCOFs) have been synthesized via imine condensation. The obtained frameworks show crystallinity and high stability. More importantly, the AzoCOFs exhibit exceptionally high ideal adsorption solution theory (IAST) selectivity in adsorption of C2H2 (35-2891) over CH4 at 273 K and 1 bar, owing to the favorable interactions between azo groups and acetylene molecules. The dependence of the gas adsorption property on pore size and polarity of the frameworks was also studied. The triethylene glycol substituted Tg-AzoCOF shows the highest C2H2/CH4 selectivity (IAST selectivity of 2891), which represents the highest reported for all porous materials. The AzoCOFs also exhibit high IAST adsorption selectivity of C2H4/CH4 (11-20), C2H6/CH4 (15-22), and CO2/CH4 (12-37), which is comparable with most porous materials, thus showing their great potential in gas separation applications.

Lumbar disc herniation (LDH) with radicular pain is a common and complicated musculoskeletal disorder. Our previous study showed that LDH-induced methylglyoxal (MG) accumulation contributed to radicular pain. The underlying mechanisms through which MG accumulates are poorly understood. In the present study, we found that both MG and tumor necrosis factor-alpha (TNF-ɑ) levels in the herniated disc of patients with radicular pain were significantly increased, and the activity of Glyoxalase 1 (GLO1), the rate-limiting enzyme that metabolizes MG, was decreased. In rats, the LDH model was mimicked by implantation of autologous nucleus pulposus (NP) to the left lumbar five spinal nerve root. The mechanical allodynia was observed in LDH rats. Besides, MG and TNF-ɑ levels were increased, and GLO1 activity was significantly decreased in the implanted NP. In cultured rat NP cells, stimulation with the inflammatory mediator TNF-ɑ reduced GLO1 activity and expression. These results suggested that TNF-ɑ-induced GLO1 activity decrease contributed to MG accumulation in the herniated disc of patients with radicular pain.

Ionic covalent organic frameworks (ICOFs) have recently emerged as promising candidates for solid-state electrolytes. Herein, we report the first example of a series of crystalline imidazolate-containing ICOFs as single-ion conducting COF solid electrolyte materials, where lithium cations freely travel through the intrinsic channels with outstanding ion conductivity (up to 7.2 × 10-3 S cm-1) and impressively low activation energy (as low as 0.10 eV). These properties are attributed to the weak Li ion-imidazolate binding interactions and well-defined porous 2D framework structures of such ICOFs. We also investigated the structure-property relationship by varying the electronic properties of substituents (electron donating/withdrawing) that covalently attached to the imidazolate groups. We found electron-withdrawing substituents significantly improve the ion-conducting ability of imidazolate-ICOF by weakening ion-pair interactions. Our study provides a convenient bottom-up approach toward a novel class of highly efficient single-ion conducting ICOFs which could be used in all solid-state electrolytic devices.

Diabetic retinopathy (DR) is the common cause of diabetic vascular complications. The NOD-like receptor (NLR) family, pyrin domain containing 1 (NLRP1), also known as NALP1, inflammasome is the first member of the NLR family to be discovered, playing an important role in inflammatory response. However, its effect on DR development has not been reported. In the study, the wild type (WT) and NLRP1−/− mice were injected with streptozotocin (STZ) to induce DR. The results indicated that NLRP1−/− significantly increased bodyweight reduction and decreased blood glucose levels induced by STZ. WT/DR mice exhibited higher levels of NLRP1 in retinas. NLRP1−/− ameliorated retinal abnormalities in DR mice using H&E staining. In addition, attenuated avascular areas and neovascular tufts were also observed in NLRP1−/−/DR mice. The levels of pro-inflammatory cytokines in serum and retinas were highly induced in WT/DR mice, whereas being markedly reduced by NLRP1−/−. In addition, vascular endothelial growth factor (VEGF) and Iba1 expressions induced by STZ in serum or retinas were significantly down-regulated in NLRP1−/−/DR mice. Consistently, NLRP1−/− attenuated ASC and Caspase-1 expressions in retinas of DR mice. Compared to WT/DR group, NLRP1−/− markedly decreased retina p-nuclear factor-κB (NF-κB), interleukin-1β (IL-1β) and IL-18 levels. And similar results were confirmed in vitro that suppressing NLRP1/ASC inflammasome ameliorated inflammatory response in fructose-treated retinal ganglion cells. The results above indicated that the modulation of NLRP1 inflammasome might be a promising strategy for DR therapy.

A simple and versatile strategy, borrowing ideas from the chemistry of MOFs and COFs, is developed for the synthesis of coordination-supported organic polymers (COPs) via coordination between Al3+ and 5-amino-8-hydroxyquinoline together with organic imine- or imide-based polycondensation. The COPs with high surface areas (up to 1123 m2 g−1) and abundant mesopores (2.5 nm or 14 nm) possess good crystalline and porous structure after being soaked in boiling water.

Covalent organic frameworks (COFs) with well-defined and customizable pore structures are promising templates for the synthesis of nanomaterials with controllable sizes and dispersity. Herein, a thioether-containing COF has been rationally designed and used for the confined growth of ultrafine metal nanoparticles (NPs). Pt or Pd nanoparticles (Pt NPs and Pd NPs) immobilized inside the cavity of the COF material have been successfully prepared at a high loading with a narrow size distribution (1.7 ± 0.2 nm). We found the crystallinity of the COF support and the presence of thioether groups inside the cavities are critical for the size-controlled synthesis of ultrafine NPs. The as-prepared COF-supported ultrafine Pt NPs and Pd NPs show excellent catalytic activity respectively in nitrophenol reduction and Suzuki-Miyaura coupling reaction under mild conditions and low catalyst loading. More importantly, they are highly stable and easily recycled and reused without loss of their catalytic activities. Such COF-supported size-controlled synthesis of nanoparticles will open a new frontier on design and preparation of metal NP@COF composite materials for various potential applications, such as catalysis and development of optical and electronic materials.

Background Colorectal cancer (CRC) is a prevalent malignancy of the digestive tract. miR-410-3p is involved in oncogenesis and development of CRC, but the specific regulation mechanism is still not known clearly. Methods The expression of miR-410-3p and zinc finger CCHC-type containing 10 (ZCCHC10) in CRC cells was detected by qRT-PCR and western blot method, respectively. The dual-luciferase reporter gene detection was applied for determination of interaction between miR-410-3p and ZCCHC10. The wound healing assay and transwell assay were carried out to measure cell migration and invasive ability, respectively. Results The miR-410-3p expression levels were markedly increased, but ZCCHC10 levels were reduced in CRC cells and tissues. Dual-luciferase reporter gene detection indicated that miR-410-3p targeted ZCCHC10 directly. Functionally knockdown of ZCCHC10 or overexpression of miR-410-3p activated nuclear factor-κB (NF-κB) signaling pathway, promoted epithelial-mesenchymal transition (EMT) process, as well as cell migration and invasion of CRC cells. After adding NF-κB inhibitor BAY 11-708 to inhibit NF-κB pathway, the promoting effects of si-ZCCHC10 on cell migration, invasion and EMT of HT29 and SW480 cells were suppressed. Meanwhile, overexpression of ZCCHC10 inhibited the effects of miR-410-3p on cell migration, invasion and EMT of HT29 and SW480. Conclusion miR-410-3p-mediated ZCCHC10 suppression regulates NF-κB activation, thereby promoting EMT process, cell migration and invasion of CRC cells. This study provides a new insight into the specific mechanism by which miR-410-3p mediates CRC progression.

This study aims at examining the hypolipidemic effect of piceatannol on high fat diet (HFD)-induced hypercholesterolemic Sprague-Dawley rats and serum metabolite changes. Piceatannol supplement significantly lowered the total cholesterols, low density lipoprotein cholesterol levels and the atherogenic index as compared to the HFD model which only have increased dietary cholesterol intake. Using untargeted mass spectrometry-based metabolomic platforms, multivariate statistics revealed that HFD significantly perturbed fatty acids, lysophospholipids, bile acids and conjugated bile acids. Reduced CYP7A1 protein expression and increase in glycocholate and taurodeoxycholate after piceatannol treatment suggested the conjugated bile acid might contribute to the cholesterol-lowering effect. For lipid profiles, lysoPC (20:2) and lysoPC (20:0) were decreased while the ratio of esterified arachidonic acid to esterified dihomo-γ linoleic acid was up-regulated for rats after piceatannol supplement. These results indicated that the therapeutic effect of piceatannol is associated with bile acid and fatty acid metabolisms and reduced absorption of dietary cholesterols.

A novel type of porous coordination polymer with titanium alkoxide linkages (Ti-PCP) was successfully constructed through reaction of a 1,3-diol-substituted shape-persistent arylene–ethynylene macrocycle with Ti(OiPr)4. The polymer exhibits a high Brunauer–Emmett–Teller (BET) surface area (1029 m2 g−1) and good adsorption selectivity for CO2 over N2. With n-Bu4NBr as a co-catalyst, Ti-PCP can serve as a highly efficient catalyst to convert CO2 into cyclocarbonates through the cycloaddition reaction with epoxides under mild conditions. This framework-based heterogeneous catalyst not only has excellent catalytic activity, but also can be recycled and reused many times with easy product separation, thus showing its great potential for industrial applications as a green catalyst. With high uptake of CO2 and catalytic ability to convert CO2 to useful chemical compounds, this type of porous polymer with embedded catalytic centers could have important applications to solve environmental problems regarding post-combustion CO2 capture and conversion.

Equilibrative nucleoside transporters (ENTs) play a crucial role in the transport of nucleoside and nucleoside analogues, which are important for nucleotide synthesis and chemotherapy. In addition, ENTs regulate extracellular adenosine levels in the vicinity of its receptors and hence influence adenosine-related functions. The clinical applications of ENT inhibitors in the treatment of cardiovascular diseases and cancer therapy have been explored in numerous studies. However, all ENT inhibitors to date are selective for ENT1 but not ENT2. In the present study, we investigated the novel compound 4-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-6-imino-N-(naphthalen-2-yl)-1,3,5-triazin-2-amine (FPMINT) as an inhibitor of ENT1 and ENT2. Nucleoside transporter-deficient PK15NTD cells stably expressing ENT1 and ENT2 showed that FPMINT inhibited [3H]uridine and [3H]adenosine transport through both ENT1 and ENT2 in a concentration-dependent manner. The IC50 value of FPMINT for ENT2 was 5-10-fold less than for ENT1, and FPMINT could not be displaced with excess washing. Kinetic studies revealed that FPMINT reduced Vmax of [3H]uridine transport in ENT1 and ENT2 without affecting KM. Therefore, we conclude that FPMINT inhibits ENTs in an irreversible and non-competitive manner. Although already selective for ENT2 over ENT1, further modification of the chemical structure of FPMINT may lead to even better ENT2-selective inhibitors of potential clinical, physiological and pharmacological importance.

Epoxy resin (EP) modified polyurethane prepolymer (PUP) was prepared by synthesizing prepolymer method, and then EP/PU interpenetrating polymer networks (IPN) composites was produced with better adhesive properties as the foam expands further. The effects of the process on graft reaction and spatial structure of EP/PU IPN composites was studied by FT-IR and scanning electron microscopy (SEM). And a study on the adhesive properties of polyurethane foams with different content of epoxy resins was done by adhesion strength test. The adhesive strength of the IPNs composites were significantly improved when the EP content was 50%. The thermal stability and the expansion ratio of EP/PU IPNs composites were reduced slightly. The modified IPN composites were expected to be used as the preparation of high viscosity and high dilatability of the special - purpose materials in future.

Flavonoid dimer FD18 is a new class of dimeric P-gp modulator that can reverse cancer drug resistance. FD18 is a potent (EC50 = 148 nM for paclitaxel), safe (selective index = 574), and selective P-glycoprotein (P-gp) modulator. FD18 can modulate multidrug resistance toward paclitaxel, vinblastine, vincristine, doxorubicin, daunorubicin, and mitoxantrone in human breast cancer LCC6MDR in vitro. FD18 (1 μM) can revert chemosensitivity of LCC6MDR back to parental LCC6 level. FD18 was 11- to 46-fold more potent than verapamil. FD18 (1 μM) can increase accumulation of doxorubicin by 2.7-fold, daunorubicin (2.1-fold), and rhodamine 123 (5.2-fold) in LCC6MDR. FD18 inhibited P-gp-mediated doxorubicin efflux and has no effect on influx. FD18 at 1 μM did not affect the protein expression level of P-gp. Pharmacokinetics studies indicated that intraperitoneal administration of 45 mg/kg FD18 was enough to maintain a plasma level above EC50 (148 nM) for more than 600 min. Toxicity studies with FD18 (90 mg/kg, i.p. for 12 times in 22 days) with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) revealed no obvious toxicity or death in mice. In vivo efficacy studies indicated that FD18 (45 mg/kg, i.p. for 12 times in 22 days) together with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) resulted in a 46% reduction in LCC6MDR xenograft volume (n = 11; 648 ± 84 mm(3)) compared to paclitaxel control (n = 8; 1201 ± 118 mm(3)). There were no animal deaths or significant drop in body weight and vital organ wet weight. FD18 can increase paclitaxel accumulation in LCC6MDR xenograft by 1.8- to 2.2-fold. The present study suggests that FD18 represents a new class of safe and potent P-gp modulator in vivo.

Lycium barbarum fruit (Goji or wolfberry) is widely used as a functional food as well as an herb in Chinese medicine. The polysaccharides of L. barbarum (LBPs) are well-known for immunomodulation and antioxidant activities. This study evaluated the yields, properties and bioactivities of LBPs extracted from L. barbarum fruit by different methods including hot water (HWE 100 °C), ultrasonic water (UWE 30–40 °C), subcritical water (SWE 110 °C), and ultrasound-enhanced subcritical water extraction (USWE 110 °C). The total LBP yield (80 min extraction followed by ethanol precipitation) was the highest from USWE (14% w/w) and the lowest from HWE (7.6%). The LBP from USWE also showed the highest protein (27.9%) and phenolic content (5.3%, w/w), and the highest antioxidant activities (scavenging radicals by DPPH and trolox equivalent antioxidant capacity assays; ferric reducing power). It also showed the highest immunoactivities in activating the phagocytosis and NO production of RAW264.7 macrophages. USWE was proven the most efficient method for extraction of LBPs. Temperature and ultrasound were two chief factors affecting the extraction yield, chemical properties and bioactivities of LBP.

Background The role of Kdr (VEGFR-2/Flk-1) in vascular formation has been well described, but the role of Flt1 (VEGFR-1) is not well studied and is generally considered as a decoy receptor for trapping VEGF. Methods The effects of VEGFR1/2 kinase inhibitor (VRI) and calycosin on Flt1 tyrosine kinase (TK) activity were evaluated by molecular docking, enzymatic inhibition assay, protein co-immunoprecipitation and siRNA gene knock-down analysis in HUVECs. Toxicities of the chemicals were examined using HUVECs viability. Their effects on angiogenesis and vessel formation were furthered studied in HUVECs in vitro and Tg ( fli-1 : EGFP ) zebrafish in vivo . The gene and protein expression of VEGF and VEGF receptors were investigated by quantitative RT-PCR and Western blot. Results VRI strongly inhibited physiological functions of both VEGF receptors and suppressed endothelial cell survival. This resulted in blood vessel loss in zebrafish embryos. Interestingly, calycosin co-treatment impeded VRI-induced blood vessel loss. Docking and kinase inhibition assay revealed that calycosin competed with VRI for the tyrosine kinase domain of Flt1 without affecting ATP binding. On the contrary, calycosin did not affect the interaction between VRI and Kdr-TK. Consistent with these results, calycosin counteracted the inhibition of Flt1-TK and PI3K phosphorylation induced by VRI in HUVECs. Further studies in vitro and in vivo showed that the minimizing effect of calycosin on VRI-mediated endothelial cytotoxicity was blocked by wortmannin (a PI3K inhibitor). The impeding effect of calycosin on VRI-induced blood vessel loss was absent in zebrafish embryos injected with Flt1 MO. Conclusions Flt1-tyrosine kinase (TK) activity contributed significantly in endothelial cells survival and vascular development during embryo angiogenesis in zebrafish by engaging PI3K/Akt pathway. General significance The roles of Flt1 activity in endothelial cell survival in physiological vascular formation may have been previously under-appreciated.

A new fluorinated and alkylated lithium malonatoborate salt, lithium bis(2-methyl-2-fluoromalonato)borate (LiBMFMB), has been synthesized for lithium ion battery application. A 0.8 M LiBMFMB solution is obtained in a mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) (1 : 2 by wt). The new LiBMFMB based electrolyte exhibits good cycling stability and rate capability in LiNi0.5Mn1.5O4 and graphite based half-cells.

The thermodynamics and kinetics of crystallization of sodium sulfate with a tripodal tris-urea receptor (L1) from aqueous alkaline solutions have been measured in the 15–55 °C temperature range for a fundamental understanding of the elementary steps involved in this sulfate separation method. The use of radiolabeled Na235SO4 provided a practical way to monitor the sulfate concentration in solution by β liquid scintillation counting. Our results are consistent with a two-step crystallization mechanism, involving relatively quick dissolution of crystalline L1 followed by the rate-limiting crystallization of the Na2SO4(L1)2(H2O)4 capsules. We found that temperature exerted relatively little influence over the equilibrium sulfate concentration, which ranged between 0.004 and 0.011 M. This corresponds to 77–91% removal of sulfate from a solution containing 0.0475 M initial sulfate concentration, as found in a typical Hanford waste tank. The apparent pseudo-first-order rate constant for sulfate removal increase...

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural polyphenolic compound that exists in Polygonum cuspidatum, grapes, peanuts and berries, as well as their manufactured products, especially red wine. Resveratrol is a pharmacologically active compound that interacts with multiple targets in a variety of cardiovascular disease models to exert protective effects or induce a reduction in cardiovascular risks parameters. This review attempts to primarily serve to summarize the current research findings regarding the putative cardioprotective effects of resveratrol and the molecular pathways underlying these effects. One intent is to hopefully provide a relatively comprehensive resource for clues that may prompt ideas for additional mechanistic studies which might further elucidate and strengthen the role of the stilbene family of compounds in cardiovascular disease and cardioprotection. Model systems that incorporate a significant functional association with tissues outside of the cardiovascular system proper, such as adipose (cell culture, obesity models) and pancreatic (diabetes) tissues, were reviewed, and the molecular pathways and/or targets related to these models and influenced by resveratrol are discussed. Because the body of work encompassing the stilbenes and other phytochemicals in the context of longevity and the ability to presumably mitigate a plethora of afflictions is replete with conflicting information and controversy, especially so with respect to the human response, we tried to remain as neutral as possible in compiling and presenting the more current data with minimal commentary, permitting the reader free reign to extract the knowledge most helpful to their own investigations.

The hypocholesterolemic protective effect of the dried seed of Astragalus complanatus (ACS) was investigated in rats fed with normal diet, high cholesterol diet (HCD), and HCD plus 70% ethanol extract of ACS (600 mg/kg/day) by oral gavage for four weeks. ACS extract was tested to be rich in antioxidants, which may be contributed to its high content of phenolic compounds. Consumption of ACS remarkably suppressed the elevated total cholesterol (p < 0.01) and LDL-C (p < 0.001) induced by HCD. Chemical constituents of ACS extract were analyzed by ultra-performance liquid chromatography coupled with electrospray ionization orbitrap mass spectrometry and the results showed that the ACS extract mainly consisted of phenolic compounds including flavonoids and flavonoid glycosides. In addition, based on the serum fatty acid profiles, elucidated using gas chromatography-mass spectrometry, free and esterified fatty acids including docosapentaenoic acid, adrenic acid, dihomo-γ-linolenic acid and arachidonic acid were regulated in ACS treatment group. Western blot results further indicated the protein expression of peroxisome proliferator-activated receptor alpha (PPARα) (p < 0.05) in liver was upregulated in ACS treatment group. To conclude, our results clearly demonstrated that ACS provides beneficial effect on lowering HCD associated detrimental change.

The onsets of left ventricular hypertrophy (LVH) and endothelial dysfunction (ED) in diabetics, especially in those with elevated homocysteine (Hcy), precede the development of cardiovascular (CV) events. Salvianic acid A (SAA) is a renowned Traditional Chinese Medicine (TCM) that has been applied in the treatment of cardiovascular disease for many decades. In this study, we aimed (1) to investigate the CV protective effects of SAA on ameliorating LVH and ED in db/db mice with elevated blood Hcy level and (2) to decipher whether the observed CV protective effects of SAA are associated with Hcy metabolism by modulating the methylation potential and redox status in the liver of the db/db mice with elevated blood Hcy level. Our results found that the administration of SAA could significantly slow down the build-up of left ventricular mass and ameliorate ED. Immunological assay analysis on the mouse liver tissue also indicated that SAA treatment on db/db mice with elevated Hcy was associated with reduced methylation potential but improved redox status. In conclusion, we revealed that SAA has the potential to protect against the hyperglycemia- and hyperhomocysteinemia-induced oxidative stress on diabetic mice via modulation in Hcy metabolism.

Ergothioneine is a thiourea derivative of histidine found in food, especially mushrooms. Experiments in cell-free systems and chemical assays identified this compound as a powerful antioxidant. Experiments were designed to test the ability of endothelial cells to take up ergothioneine and hence benefit from protection against oxidative stress. Reverse-transcription polymerase chain reaction and Western blotting demonstrated transcription and translation of an ergothioneine transporter in human brain microvascular endothelial cells (HBMECs). Uptake of [(3)H]ergothioneine occurred by the organic cation transporter novel type-1 (OCTN-1), was sodium-dependent, and was reduced when expression of OCTN-1 was silenced by small interfering RNA (siRNA). The effect of ergothioneine on the production of reactive oxygen species (ROS) in HBMECs was measured using dichlorodihydrofluorescein and lucigenin, and the effect on cell viability was studied using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. ROS production and cell death induced by pyrogallol, xanthine oxidase plus xanthine, and high glucose were suppressed by ergothioneine. The antioxidant and cytoprotective effects of ergothioneine were abolished when OCTN-1 was silenced using siRNA. The expression of NADPH oxidase 1 was decreased, and those of glutathione reductase, catalase, and superoxide dismutase enhanced by the compound. In isolated rat basilar arteries, ergothioneine attenuated the reduction in acetylcholine-induced relaxation caused by pyrogallol, xanthine oxidase plus xanthine, or incubation in high glucose. Chronic treatment with the compound improved the response to acetylcholine in arteries of rats with streptozotocin-induced diabetes. In summary, ergothioneine is taken up by endothelial cells via OCTN-1, where the compound then protects against oxidative stress, curtailing endothelial dysfunction.

The incidence of cardiovascular diseases (CVDs) is high in both developed and developing countries. It has a high global rate of mortality and causes heavy social burden. Drugs are available for managing or treating CVDs and its complications. Consumption of dietary supplements or functional foods for reducing the risk of CVDs has also gained wide recognition by the general public. Piceatannol, an analog and metabolite of resveratrol, is a natural stilbene commonly found in the skin of grapes and wine. Piceatannol is believed to be a potent compound with certain cardiovascular therapeutic effects, such as the prevention of hypercholesterolemia, arrhythmia, atherosclerosis, and angiogenesis. It also has vasorelaxation and antioxidant activities. A comprehensive review of piceatannol concludes that piceatannol has the potential to be developed into health products for the cardiovascular system to help modern society reduce the high CVD incidence. However, further investigations are warranted in order to increase the bioavailability and understand the biological mechanisms and safety of using piceatannol.

Nowadays, continuous scientific endeavors are being directed toward low-cost, mild, scalable and reliable synthesis of graphene-based materials, in order to advance various graphene-related applications. So far, specific surface areas of current bulk graphene powders or graphene-like nanosheets are much lower than the theoretical value (2630 m2 g−1) of individual graphene, remaining a challenge for carbon chemists. Herein, mesoporous graphene-like carbon sheets with high specific surface area (up to 2607 m2 g−1) and high pore volume (up to 3.12 cm3 g−1) were synthesized by using polyimide chemistry in the molten salt “solvent.” In this process, abundant pyromellitic dianhydride and aromatic diamine undergo polycondensation together with further carbonization in molten KCl–ZnCl2, in which in situ formed linear aromatic polyimide with a sp2 hybridized carbon skeleton could be directly coupled and rearranged into a two-dimensional graphene-like nanosheet around the “salt scaffold”. Carbon nanosheets with well-defined mesopores (∼3.5 nm) could be easily obtained by washing salt melts in water, while the salts could be recovered and reused for the subsequent reaction. The nitrogen atoms in amine also afforded the resulting carbon with uniform foreign atoms (nitrogen content = ∼6%). Moreover, holey carbon sheets with well-dispersed and through-plane nanoholes (diameter: 5–10 nm) could be constructed by using different monomers. Being a potential electrode material in supercapacitors, the as-made carbon nanosheet possessed a significant specific capacitance (131.4–275.5 F g−1) even at a scan rate of 2000 mV s−1. Additionally, powerful nanohybrids of carbon sheet–Co3O4 were also prepared with good performance in the aerobic oxidation of alcohols and amines to aldehydes and imines, respectively.

The oxidation behavior of CeFe4Sb12 compound in air was studied in this work. x-Ray diffractometry, scanning electron microscopy observation, and activation energy calculation suggest that CeFe4Sb12 is very easily oxidized at elevated temperature. The reason for the weak resistance to oxidation is mainly due to the unstable “FeSb3” structure and the high Ce filling fraction in the skutterudite voids. At elevated temperature, Ce fillers which have high oxygen affinity firstly react with oxygen. This process proceeds accompanied by decomposition of “Fe4Sb12” into FeSb2 and Sb, which in turn accelerates the oxidation rate. The Ce fillers in CeFe4Sb12 provide a short path for rapid interdiffusion of oxygen, which leads to fast growth of the oxide layer, with thickness of about 200 μm at 900 K after only 1 h exposure in air. This result suggests that appropriate protection from oxidation is necessary for real applications of CeFe4Sb12.

Polycrystalline samples of Ba x CoO 2 ( x = 0.19, 0.28, 0.30, 0.33) were prepared by an ion-exchange technique. The high-temperature thermoelectric properties were measured for the first time. The electrical and thermal conductivity of Ba x CoO 2 decrease with decreasing the barium content from 0.33 to 0.19, while the Seebeck coefficient is not sensitive to the barium content. The maximum ZT value is 0.21 for Ba 0.19 CoO 2 at 800 K. The results suggest that Ba x CoO 2 might be another possible candidate for thermoelectric oxide materials.

A poly (sodium acrylate)-polyvinyl alcohol superabsorbent resin is synthesized from acrylic acid (AA) and polyvinyl alcohol. A new method is established to measure the adhesion properties. Then the influence of different experimental conditions on the adhesion properties of the resin is discussed. The results indicate that the adhesion properties of super absorbent resin have some variation with the water absorption increased, the initial pressure and the separation rate. It can be explained by the theory of polymer structure, mechanical interlock and stress relaxation.

This study investigated the mechanism of the cytotoxic effect of emodin, an active anthraquinone, on human lung adenocarcinoma A549 cells. In vitro growth inhibition and suppression on colony forming were used to evaluate the effects of emodin on A549 cells. Emodin's ability in changing the expressions of apoptosis-related genes was studied by real-time RT-PCR. Emodin could significantly inhibit the growth of A549 cells with IC50 = 16.85 μg/ml (~60 μM). It also concentration dependently inhibited the colony-forming ability of A549 cells with IC50 = 7.60 μg/ml (~30 μM). Hallmarks of apoptosis, such as single-strand DNA breakage and DNA fragmentation, were observed in A549 cells treated with emodin. Emodin (72 h) treatment could up-regulate the gene expression of FASL (p < 0.05) and down-regulate the gene expression of C-MYC (p < 0.01), but induce no significant changes in the gene expressions of MCL1, GAPDH, BAX and CCND1. These results suggest that emodin could induce growth inhibition and apoptosis in A549 cells through modifying the extrinsic apoptotic pathways and the induction of cell cycle arrest.

Panax notoginseng saponins (PNS) are major active constituents of P. notoginseng. This study investigated the mechanisms of the hypocholesterolaemic and atheroscleroprotective effects of PNS. It was found that treatment of PNS (30 or 100 mg/kg/day, p.o.) could significantly reduce elevated serum total cholesterol, triacylglycerol, low-density lipoprotein cholesterol and atherogenic index induced by feeding rats with high cholesterol diet for 28 days. High-density lipoprotein cholesterol could also be increased by PNS treatment. Additionally, PNS significantly enhanced the hypercholesterolaemia-induced reduction of superoxide dismutase activity in the liver. In hypercholesterolaemic rats, PNS significantly improved the endothelium-dependent vasodilatation, acetylcholine-induced nitric oxide production and endothelial nitric oxide synthase mRNA expression in a dose-dependent manner. It also significantly reversed the hypercholesterolaemia-induced changes in mRNA expressions of cholesterol 7α-hydroxylase and peroxisome proliferator-activated receptor α but not HMG-CoA reductase. The findings provided evidence for using PNS to prevent the development of hypercholesterolaemia and atherosclerosis. The hypocholesterolaemic activity of PNS is likely to be resulted from inducing the biosynthesis of bile acids from cholesterol and promoting the β-oxidation of fatty acids in the liver. The vasoprotective function of PNS may be brought about by increasing the gene expression of eNOS in endothelial cells, its antioxidative activity, or both.

Consumption of functional foods for managing plasma cholesterol level has gained acceptance globally. The hypocholesterolaemic and vascular protective effects of the dried fruit of Crataegus pinnatifida, hawthorn (Shan Zha), were investigated in rats fed with normal diet, high cholesterol diet (HCD) or HCD plus Shan Zha 80% ethanolic extract treatment (30 or 100 mg/kg/day, p.o.) for 4 weeks. Shan Zha extract markedly reversed the increased plasma total cholesterol and high density lipoprotein cholesterol induced by HCD with a dose-dependent improvement on the atherogenic index. It also demonstrated good hepatoprotective function by reducing lipid content in the liver. The blunted endothelium-mediated aortic relaxation in HCD-fed rats was restored by high dosage of Shan Zha extract treatment. The current results showed that Shan Zha extract could provide its cholesterol lowering effect by up-regulating hepatic CYP7A1 mRNA expression which leads to enhanced bile acid biosynthesis. It is postulated that the hypocholesterolaemic effect is the primary beneficial effect given by Shan Zha extract; it then leads to other secondary beneficial effects such as vascular protective and hepatoprotective functions. Thus, Shan Zha extract could provide an overall improvement on the hepatic and vascular systems that may be important in relieving hypercholesterolaemia-related complications.

Co-crystallization of two urea-functionalized ligandswith tetrabutylammonium (TBA) dihydrogen phosphate resulted in the isolation of discrete (H2PO4–)4 and (H2PO4–)6 clusters stabilized in the crystalline state by multiple urea hydrogen bonds. Structural analysis by single-crystal X-ray diffraction, combined with a Cambridge Structural Database survey of (H2PO4–)n aggregates, established that these clusters display unique topologies and hydrogen-bonding connectivities.

Gui-ling-gao (GLG), also known as turtle jelly, is a popular medicinal Chinese health/functional food prepared from several traditional Chinese medicinal herbs. The present study aimed at examining and explaining the anti-inflammatory properties of GLG by using lipopolysaccharide (LPS)-induced inflammation in splenocytes isolated from BALB/c mice. Additionally, the effects of GLG on mRNA and protein expressions of inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines in LPS-stimulated splenocyte proliferation were evaluated by real-time RT-PCR and Western blot assays. We demonstrated that GLG significantly inhibited LPS-induced splenocyte proliferation in a concentration-dependent manner. LPS-mediated up-regulations in the gene and protein expressions of iNOS, interleukin-1β (IL-1β) and tumour necrosis factor-alpha (TNF-α) were suppressed by GLG. These findings suggest for the first time that GLG exerts anti-inflammatory effects by inhibiting the expression of iNOS and pro-inflammatory cytokines such as IL-1β and TNF-α. The current study provides strong scientific evidence for the health-beneficial claim that consumption of GLG could help the body to modulate the immune system.

The dried ripe seed ofRaphanus sativusL., commonly known as radish seed (or Raphani Semen), is used as traditional Chinese medicine (TCM) to treat constipation, chronic tracheitis, and hypertension. The major active compounds in Raphani Semen are alkaloids, glucosinolates, brassinosteroids, and flavonoids. Fatty acids are its main nutritional contents. Raphani Semen has been demonstrated to have beneficial effects on hypertension, obesity, diabetes mellitus, constipation, and cough. So far, there is no report about the adverse/toxic effects of this herb on humans. However, Raphani Semen processed by roasting was reported to exhibit some adverse effects on mice. Additionally, erucic acid, the main fatty acid in Raphani Semen, was shown to enhance the toxicity of doxorubicin. Thus, Raphani Semen has a potential risk of causing toxicity and drug interaction. In summary, Raphani Semen is a valuable TCM herb with multiple pharmacological effects. More studies on Raphani Semen could help better understand its pharmacological mechanisms so as to provide clear scientific evidence to explain its traditional uses, to identify its therapeutic potential on other diseases, and to understand its possible harmful effects.

Post-menopause, there is an increase in body weight, visceral adiposity, and risk of developing non-alcoholic fatty liver disease (NAFLD), which leads to various cardiovascular diseases (CVDs). Some natural products have proven useful for counteracting the detrimental effects of menopause. The rhizome of Ligusticum chuanxiong Hort. (LC) is a well-known medicinal herb widely used in Chinese communities for the treatment of CVDs. The hepatic and vascular protective effects of LC ethanolic extract under postmenopausal conditions were investigated on ovariectomized (OVX) rats supplemented with or without LC ethanolic extract (600 mg/kg body weight/day, p.o.) or 17β-estradiol (1 mg/kg body weight/day, p.o.) for 12 weeks. The current findings demonstrated that consumption of LC ethanolic extract could reduce the body weight gain, improve serum lipid profile (lowering low density lipoprotein cholesterol but raising high density lipoprotein cholesterol), combat NAFLD, and protect vascular endothelium in the OVX rats. The beneficial effects of LC may be associated with its antioxidant or vasorelaxant compounds, which enhance the levels of hepatic antioxidant enzymes and up-regulate endothelial nitric oxide synthase mRNA expression, respectively. Taken together, LC may be a promising natural supplement for postmenopausal women to prevent NAFLD and CVDs.

A series of interpenetrating polymer networks (IPN) spongy foams based on polyurethane (PU) and epoxy resin (EP) were prepared by a simultaneous polymerization technique. The PU/EP IPN spongy foams with different epoxy content were investigated. The results showed that initial adhesion increased with the increment of EP content, and gained the highest value when the content reached to 20%; FTIR suggested the formation of PU/EP IPN; the density also increased with the increasing content of epoxy; the highest degree of uniformity in bubbles were observed in foams with 20% content of epoxy resin.

Some of the major components of Danshen (Salvia miltiorrhiza), a widely used Chinese herbal medicine rich in phenolic acids, are thermosensitive and may degrade to other phenolic acids during extractions with heating. The chemical profiles of Danshen water-extract may vary with different heat water extraction at different temperatures, affecting the composition and bioactivity of the extracts. In this study, six water-extracts of Danshen obtained from heat reflux water extraction and microwave-assisted extraction with water (MAE-W) at different temperatures were tested for their composition and pharmacological effects. Among these extracts, the third-round MAE-W (100°C) extract had the highest phenolic acids and tanshinones contents, with the strongest antioxidant activity in 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) assay and ferric reducing/antioxidant potential (FRAP) assay. This extract also showed the strongest inhibitory effects on 2,2'-azobis-2-amidinopropane (AAPH)-induced hemolysis in human red blood cells, hydrogen peroxide-induced apoptosis in rat heart H9c2 cells and the highest relaxation effects on rat basilar artery. The antioxidant effects of Danshen water-extracts linearly correlated to their relaxation effects (r=0.895-0.977). Through multiple linear regression analysis, danshensu was found to be the most significant marker in the antioxidant and vasodilation effects of Danshen water-extract, while tanshinone IIA as the marker on hydrogen peroxide-induced apoptosis in rat heart H9c2 cells. Danshensu is, therefore, a useful marker for the quality control of Danshen water-extracts in antioxidant and vasodilation, while tanshinone IIA for anti-apoptotic potential of different extracts.

Background This study reported a comprehensive approach (comparing the extraction yields, chemical profiles, antioxidant properties and CYP450-inhibitory effects) to evaluated the effectiveness of various extraction methods [microwave-assisted extraction using water (MAE-W), heat reflux extraction using water (HRE-W), ultrasonic extraction using 70 % ethanol and ultrasonic extraction using ethanol (UE-E)] for Huang-Qin (HQ), the dried root of Scutellaria baicalensis Georgi. Results The HQ extraction efficiency by MAE-W was the best. The chemical profiles of extracts obtained using HRE-W and MAE-W were similar; whereas more flavones but less flavone glycosides were detected in the UE-E extract. There was no difference in the antioxidant properties among different extracts. In vitro human liver microsome assays illustrated that all extracts possessed herb–drug interaction potentials but the UE-E extract are shown with a potent interaction with CYP3A4-metabolized drugs. Conclusion MAE-W is a favorable method for the preparation of HQ extracts based on extraction yield, pharmacological properties and safety.

Cardiovascular disease (CVD) is a category of chronic noncommunicable diseases causing high global mortality and has been a heavy social burden in many countries. In the search of chemicals that arise from natural food source, allicin is one such ingredient from garlic that was discovered with the potential to provide beneficial effects to the cardiovascular system. From the pharmacokinetic studies, allicin is known to be hydrophobic and can be readily absorbed through the cell membrane without inducing any damage to the phospholipid bilayer and then rapidly metabolized to exert pharmacological effects that are important to the cardiovascular system. It was found to provide cardio-protective effects by inducing vasorelaxation and alleviating various pathological conditions of CVD, including cardiac hypertrophy, angiogenesis, platelet aggregation, hyperlipidemia and hyperglycemia. Allicin was also discovered to further protect the cardiovascular system by enhancing the antioxidant status by lowering the level of reactive oxygen species and stimulating the production of glutathione. Other pharmacological benefits such as anticancer and antimicrobial activities were also discussed. It is concluded that allicin can be potentially developed into a health product for the cardiovascular system.

Hypercholesterolemia is a major risk factor for the development of cardiovascular disease and nonalcoholic fatty liver disease. Natural compounds have been proved to be useful in lowering serum cholesterol to slow down the progression of cardiovascular disease and nonalcoholic fatty liver disease. In the present study, the hypocholesterolemic and hepatoprotective effects of the dietary consumption of chlorogenic acid were investigated by monitoring plasma lipid profile (total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein) in Sprague-Dawley rats fed with a normal diet, a high-cholesterol diet or a high-cholesterol diet supplemented with chlorogenic acid (1 or 10 mg/kg/day p.o.) for 28 days. Chlorogenic acid markedly altered the increased plasma total cholesterol and low-density lipoprotein but decreased high-density lipoprotein induced by a hypercholesterolemic diet with a dose-dependent improvement on both atherogenic index and cardiac risk factor. Lipid depositions in liver were attenuated significantly in hypercholesterolemic animals supplemented with chlorogenic acid. It is postulated that hypocholesterolemic effect is the primary beneficial effect given by chlorogenic acid, which leads to other secondary beneficial effects such as atheroscleroprotective, cardioprotective and hepatoprotective functions. The hypocholesterolemic functions of chlorogenic acid are probably due to the increase in fatty acids unitization in liver via the up-regulation of peroxisome proliferation-activated receptor α mRNA.

The anticancer effects of traditional Chinese medicine (TCM) have attracted the attention of the public vis-à-vis existing cancer therapies with various side effects. Lycium barbarum fruit, commonly known as Gou Qi Zi in China, is a potential anticancer agent/adjuvant. Its major active ingredients, L. barbarum polysaccharides (LBP), scopoletin and 2-O-β-D-glucopyranosyl-L-ascorbic acid (AA-2βG), are found to have apoptotic and antiproliferative effects on cancer cell lines. Moreover, LBP also contributes to body's immunomodulatory effects and enhances effects of other cancer therapies. It is not known whether there are any undesirable effects. Further studies on its pharmacological mechanisms and toxicology could facilitate a safe usage of this TCM herb.

Two types (imine and boronate) of covalent organic frameworks (COFs) having a porphyrin unit have been synthesized. The two highly crystalline porphyrin COFs (COF-366 and COF-66) display excellent chemical and thermal stability and are permanently porous. Two-dimensional extended layered structures of the two COFs demonstrate very high charge carrier mobility values (8.1 cm2 V−1 s−1).

The hypocholesterolemic and atheroscleroprotective potentials of dietary consumption of hawthorn (dried fruit of Crataegus pinnatifida , Shan Zha) were investigated by monitoring plasma lipid profiles and aortic relaxation in Sprague–Dawley rats fed with either normal diet, high-cholesterol diet (HCD) or HCD supplemented with hawthorn powder (2%, w/w) (4 weeks). In HCD-fed rats, an increased plasma total cholesterol and LDL-cholesterol with a decreased HDL-cholesterol was observed, and consumption of hawthorn markedly suppressed the elevated total cholesterol and LDL-lipoprotein levels plus an increased HDL-cholesterol level. The blunted acetylcholine-induced, endothelium-dependent relaxation of isolated aortas of HCD-fed rats was improved by hawthorn. The development of fatty liver, an increased nitric oxide synthase (NOS) activity and an elevated oxidative stress (as estimated by the attenuated levels of anti-oxidant enzymes) associated with HCD were attenuated by hawthorn. Thus, the results demonstrated that hawthorn consumption provides overall beneficial effects on reversing HCD associated detrimental changes.

We evaluated the vasorelaxation effects of formononetin, an isoflavone/phytoestrogen found abundantly in Astragalus mongholicus Bunge, on rat isolated aorta and the underlying mechanisms involved. Cumulative administration of formononetin, genistein, daidzein and biochanin A relaxed phenylephrine-preconstricted aorta. Formononetin and biochanin A caused a similar magnitude of relaxation whereas daidzein was least potent. Mechanical removal of endothelium, L-NAME (100 microM) and methylene blue (10 microM) suppressed formononetin-induced relaxation. Formononetin increased endothelial nitric oxide (NO) synthase (eNOS), but not inducible NO synthase, activity with an up-regulation of eNOS mRNA and p-eNOS(Ser1177) protein expression. In endothelium-denuded preparations, formononetin-induced vasorelaxation was significantly reduced by glibenclamide (3 microM) and iberiotoxin (100 nM), and a combination of glibenclamide (3 microM) plus iberiotoxin (100 nM) abolished the relaxation. In contrast, formononetin-elicited endothelium-independent relaxation was not altered by ICI 182,780 (10 microM, an estrogen receptor (ER alpha/ER beta) antagonist) or mifepristone (10 microM, a progesterone receptor antagonist). In single aortic smooth muscle cells, formononetin caused opening of iberiotoxin-sensitive Ca(2+)-activated K(+) (BK(Ca)) channels and glibenclamide-sensitive adenosine triphosphate (ATP)-dependent K(+) (K(ATP)) channels. Thus, our results suggest that formononetin caused vascular relaxation via endothelium/NO-dependent mechanism and endothelium-independent mechanism which involves the activation of BK(Ca) and K(ATP) channels.

A validated high performance liquid chromatographic (HPLC) method with dual wavelength detection was developed and applied to the determination of chlorogenic acid in rat plasma. Elution was performed on C18 column at 27°C with acetronitrile–water (0.2% phosphoric acid, pH = 2.0) at different proportions according to a time scheduled programme and pumped at a flow rate of 1.0 mL min−1. The eluent was detected at 325 nm for chlorogenic acid and 370 nm for the internal standard, kaempferol. The intra-day and inter-day precisions were better than 3.58% and 3.66%, respectively. The standard curve for chlorogenic acid was linear (r2 = 0.9993) in the concentration range of 0.1–15 μg mL−1. Accuracy in the measurement of samples ranged from 91.97 to 101.81%. The limit of detection and the limit of quantification for chlorogenic acid in plasma were 30 and 90 ng mL−1, respectively. This assay has been successfully applied in the pharmacokinetic study of chlorogenic acid through oral and intravenous administration i...

Hypercholesterolemia is a major risk factor for the development and progression of cardiovascular diseases including atherosclerosis. A major ac tive ingredient, scutellarin, from the plant Erigeron breviscapus was investigated for its hypocholesterolemic and atheroscleroprotective effects (30 and 100 mg/kg/day, p. o.). The serum lipid profile (total cholesterol, triglycerides, high density lipoprotein cholesterol and low density lipoprotein cholesterol) was monitored and aortic functions in Sprague-Dawley rats fed with normal diet, atherogenic diet or atherogenic diet plus oral administration of either scutellarin or simvastatin (a positive control) were tested. It was found that scutellarin markedly attenuated the increased serum total cholesterol induced by atherogenic diet. It caused a significant reduction in the atherogenic index. In addition, scutellarin administration could significantly enhance acetylcholine-induced nitrate/nitrite production, increase the gene expression of endothelial nitric oxide synthase and improve acetylcholine-induced endothelium-dependent vasorelaxation in rat isolated aortas. These data revealed that scutellarin could reduce the atherogenic properties of dietary cholesterol in rats. However, whether scutellarin's atheroscleroprotective potential targets endothelial function directly or indirectly on its antioxidative activity remains to be determined.

Scutellaria baicalensis Georgi (Labiatae) (“huang qin”), Ligusticum chuanxiong Hort. (Umbelliferae) (“chuang xiong”), Panax notoginseng (Burk.) F.H. Chen (Araliaceae) (“san qi”), Uncaria rhynchophylla (Miq.) Jackson. (Rubiaceae) (“gou teng”), Rhokiola rosea L. (Crassulaceae) (“hong jing tian”) and Stephania tetrandra S. Moore (Menispermaceae) (“fang ji”) are commonly used traditional Chinese medicine (TCM) for hypertensive patients. The pharmacologically active compounds found in these TCMs are baicalin, ligustrazine, notoginsenoside R1, rhynchophylline, salidroside and tetrandrine, respectively, which possess antihypertensive properties with diverse cellular mechanisms. In this study, we attempted to evaluate a possible correlation of the antioxidative activities (using the DPPH assay) and the vaso-relaxation effects (using rat isolated thoracic aorta) of these compounds. In the antioxidative study, a relative order of free radical scavenging capacity (SR%) of baicalin ≥ tetradrine >> salidroside ≥ ligus...

Nanoparticles based on amorphous poly(3-hydroxybutyrate)–poly(ethylene glycol)–poly(3-hydroxybutyrate) (PHB-PEG-PHB) are potential drug delivery vehicles, and so their cytotoxicity and hemolysis assay were investigated in vitro using two kinds of animal cells. The PHB-PEG-PHB nanoparticles showed excellent biocompatibility and had no cytotoxicity on animal cells, even when the concentrations of the PHB-PEG-PHB nanoparticle dispersions were increased to 120 μg/mL. Moreover, no hemolysis was detected with the PHB-PEG-PHB nanoparticles, suggesting that the PHB-PEG-PHB nanoparticles were obviously much hemocompatible for drug delivery applications. In the presence of intracellular enzyme esterase, the biocompatible PHB-PEG-PHB nanoparticles might be hydrolyzed, and their biodegradable behavior was monitored by the fluorescence spectrum and the pH meter. The initial biodegradation rate of the PHB-PEG-PHB nanoparticles was closely related to the enzymatic amount and the PHB block length. Compared with that obtained from the fluorescence determination, the initial biodegradation rate from pH measurement was faster. The biodegraded products mainly consisted of 3HB monomer and dimer, which were the metabolites present in the body. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 87A: 290–298, 2008

Sequential extraction with petroleum ether, chloroform–ethyl acetate, methanol, and water was carried out on 40 commonly used Chinese medicinal herbs. The antioxidant power of different fraction extracts was measured with both the DPPH assay and the FRAP assay. Ascorbic acid and butylated hydroxytoluene were used as two reference antioxidants. The total phenolic content of the extracts was measured by Folin-Ciocalteu method. The fraction extracts showed different antioxidant activity in the two assays; however, there was a significant positive correlation between the DPPH assay and the FRAP assay. Methanol fraction extracts generally demonstrated stronger antioxidant power and higher total phenolic content than did the others. The results suggest that Radix Sanguisorbae, Cortex cinnamomi, Herba taxilli, Semen arecae, and L., Cinnamomum cassia Presl ., Taxillus sutchuenensis (Lecomte) Danser, Areca catechu Linn. and Scutellaria baicalensis Georgi contain relatively high values in antioxidant power ...

In this study, we determined the in vitro effect of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activation on the aortic relaxation, lipolysis and insulin-induced [(3)H]-glucose uptake of the abdominal (omental) adipocytes of the non-diabetic (+db/+m) and obese/diabetic (+db/+db) mice. The expression of PPAR-gamma (mRNA and protein) in aorta and adipose tissues was evaluated and compared. Cumulative application of ciglitazone, pioglitazone and troglitazone (PPAR-gamma agonists) caused a concentration-dependent aortic relaxation (sensitive to 2-chloro-5-nitro-N-phenylbenzamide (GW9662) (1 microM, a selective PPAR-gamma antagonist) and N(omega)-nitro-l-arginine methyl ester (l-NAME) (20 microM, a nitric oxide synthase inhibitor)) with a maximum relaxation of approximately 30% (3 microM) in +db/+m mice, whereas no relaxation was observed in +db/+db mice. All PPAR-gamma agonists examined did not alter the basal lipolysis of both species, but forskolin caused a concentration-dependent lipolysis, with a greater magnitude observed in +db/+m mice. Insulin (0.1 and 1 microM) caused an enhancement of [(3)H]-glucose uptake into adipocytes with a greater magnitude in +db/+m mice. In contrast, none of the PPAR-gamma agonists tested (0.1, 1 and 10 microM) altered the basal and the insulin (0.1 microM)-induced [(3)H]-glucose uptake into adipocytes of both species. In addition, there was no difference in PPAR-gamma expression (mRNA and protein) in the aorta and adipose tissues between the species. In conclusion, our results demonstrate that PPAR-gamma is present in the abdominal (omental) adipose tissue and thoracic aorta. An acute activation of PPAR-gamma produced a small ( approximately 30%) aortic relaxation (nitric oxide/endothelium-dependent) of +db/+m mice. However, all PPAR-gamma agonists examined have no acute effect on lipolysis and the insulin-induced glucose uptake into adipocytes of both +db/+m and +db/+db mice.

We evaluated the acute effect of homocysteine on the iberiotoxin-sensitive, Ca 2+ -activated K + (BK Ca ) channels of the porcine coronary artery smooth muscle cells. NS 1619 (1 to 30 μM) caused a concentration-dependent enhancement of the BK Ca amplitude (recorded using the whole-cell, membrane-rupture configuration) only with an elevated [Ca 2+ ] i of ∼ 444 nM, but not with [Ca 2+ ] i of ∼ 100 nM. Homocysteine (30 μM) caused a small inhibition (∼ 16%) of the BK Ca amplitude ([Ca 2+ ] i = ∼ 444 nM), and a greater inhibition (∼ 77%) was observed with 100 μM NADH present in the pipette solution. The inhibition persisted after washing. With NADPH (100 μM), a smaller magnitude of inhibition (∼ 34%) of the BK Ca amplitude was recorded. The NS 1619-mediated enhancement of the BK Ca amplitude (with elevated [Ca 2+ ] i plus NADH in the pipette) was attenuated by homocysteine. The homocysteine-mediated inhibition of the BK Ca amplitude was suppressed by Tiron (10 mM) or diphenylene iodonium (30 nM), applied alone, but not by superoxide dismutase (500 U/ml) and catalase (500 U/ml). Generation of superoxide ( O 2 − ) of the smooth muscle cells (with NADH presence), measured using the lucigenin-enhanced chemiluminescence, was markedly increased by angiotensin II (100 nM) and homocysteine (30 μM). The chemiluminescence signal was sensitive to apocynin (300 μM) or Tiron, applied alone, but not to superoxide dismutase and catalase. In conclusion, our results demonstrate that acute homocysteine application inhibits the iberiotoxin-sensitive BK Ca channels (with elevated [Ca 2+ ] i and NADH present) which is probably caused by the NADH oxidase activation and the concomitant generation of intracellular superoxide.

A high performance liquid chromatographic method was developed and applied to the simultaneous determination of puerarin and danshensu in a traditional Chinese medicinal preparation containing Pueraria lobata and Salvia miltiorrhiza as its major herbal constituents. Elution was performed on a C18 column at 27°C with acetonitrile–water (0.5% acetic acid) at different proportions according to a time scheduled programme, and pumped at a flow rate of 1.0 mL/min. Indomethacin was used as an internal standard. High resolution was obtained between the analytes and the internal standard. The intra‐day and inter‐day precisions were better than 1.9% and 2.2%, respectively. The coefficient of determination for each analyte was above 0.997. It is a simple and sensitive analytical method with good accuracy and reproducibility.