Determination of hyoscyamine and scopolamine in serum and urine of humans by liquid chromatography with tandem mass spectrometry

A simple method was developed for the analysis of hyoscyamine and scopolamine in human serum and urine using liquid chromatography with tandem mass spectrometry (LC/MS/MS). Hyoscyamine and scopolamine in serum and urine were cleaned up with an Oasis HLB cartridge and a PSA cartridge. The LC separation was carried out on an ODS column, using linear gradient elution with 5 mmol/L IPCC-MS3-methanol as the mobile phase. The mass spectral acquisition was done in the positive ion mode by applying selected reaction monitoring (SRM). The recoveries of hyoscyamine and scopolamine were 86.0-105% from human serum and urine fortified at 0.2 ng/mL and 10 ng/mL. The detection limits of hyoscyamine and scopolamine were 0.02 ng/mL. Four serum and three urine samples of humans poisoned by eating Datura innoxia Mill. were analyzed by this method. Hyoscyamine and scopolamine were detected at the levels of 0.45-3.5 ng/mL in all serum samples and 170-670 ng/mL in all urine samples.     

Amelioration of scopolamine induced cognitive dysfunction and oxidative stress by Inonotus obliquus - a medicinal mushroom

The present study was aimed to investigate the cognitive enhancing and anti-oxidant activities of Inonotus obliquus (Chaga) against scopolamine-induced experimental amnesia. Methanolic extract of Chaga (MEC) at 50 and 100 mg kg (-1)doses were administered orally for 7 days to amnesic mice. Learning and memory was assessed by passive avoidance task (PAT) and Morris water maze (MWM) test. Tacrine (THA, 10 mg kg (-1), orally (p.o)) used as a reference drug. To elucidate the mechanism of the cognitive enhancing activity of MEC, the activities of acetylcholinesterase (AChE), anti-oxidant enzymes, the levels of acetylcholine (ACh) and nitrite of mice brain homogenates were evaluated. MEC treatment for 7 days significantly improved the learning and memory as measured by PAT and MWM paradigms. Further, MEC significantly reduced the oxidative-nitritive stress, as evidenced by a decrease in malondialdehyde and nitrite levels and restored the glutathione and superoxide dismutase levels in a dose dependent manner. In addition, MEC treatment significantly decreased the AChE activity in both the salt and detergent-soluble fraction of brain homogenates. Further, treatment with MEC restored the levels of ACh as did THA. Thus, the significant cognitive enhancement observed in mice after MEC administration is closely related to higher brain anti-oxidant properties and inhibition of AChE activity. These findings stress the critical impact of Chaga, a medicinal mushroom, on the higher brain functions like learning and memory.     

Nondestructive determination of fatty acid composition of husked sunflower (Helianthus annua L.) seeds by near-infrared spectroscopy

Determination of the fatty acid composition of sunflower (Helianthus annua L.) seeds by near-infrared (NIR) spectroscopy was examined. Sunflower seeds were husked (removed from their hulls by a husking machine or manually with a knife). NIR spectra of these seeds were scanned from 1100 to 2500 nm at 2-nm intervals in a whole-grain cell with a wideangle moving drawer for machine-husked seeds or in a single-grain cup for a manually husked single-grain seed. The extracted oils from machine-husked seeds also were scanned by sandwiching them between a pair of slide glasses to create a thin layer and by placing them on a syrup cup. For extracted oil, the absorption band around 1720 nm filled out to the shorter wavelength region in the NIR second-derivative spectra as the percentage of the linoleic acid moiety increased, because linoleic acid absorbs in this region. On the other hand, for husked seeds and for a single-grain seed, as the percentage of linoleic acid increased, the trough at 1724 nm where oleic and saturated acids absorb decreased in the second-derivative NIR spectra. Determination of the fatty acid composition of sunflower seeds could be carried out successfully according to the NIR spectral pattern for both extracted oil (r=−0.989) and kernel seed (r=−0.993). This is important, especially for a manually husked single-grain seed (r=−0.971), because it can still be germinated after such nondestructive analysis.     

Kinetic Study of the Prooxidant Effect of α-Tocopherol. Hydrogen Abstraction from Lipids by α-Tocopheroxyl Radical

A kinetic study of the prooxidant effect of α-tocopherol was performed. The rates of allylic hydrogen abstraction from various unsaturated fatty acid esters (ethyl stearate 1, ethyl oleate 2, ethyl linoleate 3, ethyl linolenate 4, and ethyl arachidonate 5) by α-tocopheroxyl radical in toluene were determined, using a double-mixing stopped-flow spectrophotometer. The second-order rate constants (k _p) obtained are <1 × 10⁻² M⁻¹ s⁻¹ for 1, 1.90 × 10⁻² M⁻¹ s⁻¹ for 2, 8.33 × 10⁻² M⁻¹ s⁻¹ for 3, 1.92 × 10⁻¹ M⁻¹ s⁻¹ for 4, and 2.43 × 10⁻¹ M⁻¹ s⁻¹ for 5 at 25.0 °C. Fatty acid esters 3, 4, and 5 contain two, four, and six –CH₂– hydrogen atoms activated by two π-electron systems (–C=C–CH₂–C=C–). On the other hand, fatty acid ester 2 has four –CH₂– hydrogen atoms activated by a single π-electron system (–CH₂–C=C–CH₂–). Thus, the rate constants, k _abstr/H, given on an available hydrogen basis are k _p/4 = 4.75 × 10⁻³ M⁻¹ s⁻¹ for 2, k _p/2 = 4.16 × 10⁻² M⁻¹ s⁻¹ for 3, k _p/4 = 4.79 × 10⁻² M⁻¹ s⁻¹ for 4, and k _p/6 = 4.05 × 10⁻² M⁻¹ s⁻¹ for 5. The k _abstr/H values obtained for 3, 4, and 5 are similar to each other, and are by about one order of magnitude higher than that for 2. From these results, it is suggested that the prooxidant effect of α-tocopherol in edible oils, fats, and low-density lipoproteins may be induced by the above hydrogen abstraction reaction.     

Temperature- and pH-responsive photosensitization activity of polymeric sensitizers based on poly-N-isopropylacrylamide

We previously reported that a copolymer consisting of N-isopropylacrylamide (NIPAM) and benzophenone (BP) units, behaves as a photosensitizer showing temperature-controlled oxygenation activity in water (J. Am. Chem. Soc.2006, 128, 8751). This polymer shows a heat-induced oxygenation enhancement at low temperature region (5-20 °C), while showing a heat-induced oxygenation suppression at high temperature region (20-60 °C), resulting in an off-on-off activity profile against the temperature window. This is driven by a heat-induced phase transition of the polymer from coil to micelle and then to globule states. In the present work, effects of adding an amine component (N-[3-(dimethylamino)propyl]acrylamide: DMAPAM) to the polymer on the sensitization activity were studied, where the relationship between the phase transition behavior and the activity was clarified by several spectroscopic analyses. The polymers, poly(NIPAM_x-co-BP_y-co-DMAPAM_z), show activity controlled by temperature and pH. The off-on-off activity profile shifts to higher temperature with a pH decrease. This is because protonation of the DMAPAM units leads to an increase in the polymer polarity and, hence, the polymer aggregates at higher temperature. In addition, increase in the DMAPAM content of the polymer leads to further shift of the activity profile. In contrast, at pH < 8, no activity enhancement is observed because complete protonation of the DMAPAM units suppresses polymer aggregation.     

Structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics for a-IGZO thin-film transistors

In this letter, we investigated the structural and electrical characteristics of high-κ Er₂O₃ and Er₂TiO₅ gate dielectrics on the amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) devices. Compared with the Er₂O₃ dielectric, the a-IGZO TFT device incorporating an Er₂TiO₅ gate dielectric exhibited a low threshold voltage of 0.39 V, a high field-effect mobility of 8.8 cm²/Vs, a small subthreshold swing of 143 mV/decade, and a high I_on/I_off current ratio of 4.23 × 10⁷, presumably because of the reduction in the oxygen vacancies and the formation of the smooth surface roughness as a result of the incorporation of Ti into the Er₂TiO₅ film. Furthermore, the reliability of voltage stress can be improved using an Er₂TiO₅ gate dielectric.     

Structural hierarchy developed in injection molding of nylon 6/clay/carbon black nanocomposites

The influence of platelet-type clay nanoparticle (nanoplatelet) on the structural evolution in injection-molded nylon 6)/carbon composites was investigated. In the absence of nanoplatelets, the nylon 6/CB systems were found to exhibit unoriented structure with nylon 6 crystalline regions exhibiting exclusively α crystal form throughout the thickness of the samples. However, inclusion of nanoplatelets induces substantial local orientation of the nylon 6 chains in the molded parts in all processing conditions and compositions. In these clay/nylon 6/CB ternary nano systems, nylon 6 matrix was found to be exclusively in γ crystal form at the skin regions and α crystal form fraction increases towards the core of the molded parts as a result of decrease in cooling rate with depth during the solidification stage. Two nanoplatelet orientation behaviors were identified: (i) in the absence of irregular shaped CB, the nanoplatelets align parallel with one another following the local flow patterns. The latter behavior also causes enhanced orientation of the nylon 6 chains undergoing substantial shear amplification trapped in between the nanoplatelets (ii) in the CB-enriched regions, nanoplatelets though still remaining parallel to one another, are randomized by following the local contours of irregular shaped CB aggregates. These CB aggregates themselves were found to organize to form trains in larger scale as a result of flow alignment.     

添加钛、铌、锰、硫及镁对亚共晶灰铸铁初生奥氏体形核及生长的影响

共晶铸铁在共晶凝固时,熔体中碳的状态,即“C的微小集合体”已经被深入研究.然而时于与初生奥氏体密切相关的铁原子的状态,即“铁的微小集合体”却缺乏研究.本文作者提出,在亚共晶灰铸铁熔体中,初晶γ的形核受“Fe的富集部”的影响,而“Fe的富集部”的形成及消失与“C的微小集合体”有关.研究表明,初生奥氏体的形核过冷度、形核数和晶核生长形貌随工艺条件如过热度、保温时间和冷却速率而变化.本文讨论了在熔体的过热度、保温时间和冷却速率固定的条件下,钛、铌、锰、硫和镁这五种添加元素对亚共晶灰铸铁初晶γ的凝固过程的影响.     

The result of a wall failure in-pile experiment under the EAGLE project

The WF (wall failure) test of the EAGLE program, in which 2 kg of uranium dioxide fuel-pins were melted by nuclear heating, was successfully conducted in the IGR (Impulse Graphite Reactor) of NNC/Kazakhstan. In this test, a 3 mm-thick stainless steel (SS) wall structure was placed between fuel pins and a 10 mm-thick sodium-filled channel (sodium gap). During the transient, fuel pins were heated, which led to the formation of a fuel-steel mixture pool. Under the transient nuclear heating condition, the SS wall was strongly heated by the molten pool, leading to wall failure. The time needed for fuel penetration into the sodium-filled gap was very short (less than 1 s after the pool formation). The result suggests that molten core materials formed in hypothetical LMFBR core disruptive accidents have a certain potential to destroy SS-wall boundaries early in the accident phase, thereby providing fuel escape paths from the core region. The early establishment of such fuel escape paths is regarded as a favorable characteristic in eliminating the possibility of severe re-criticality events. A preliminary interpretation on the WF test results is presented in this paper.     

Occurrence of 70 pharmaceutical and personal care products in Tone River basin in Japan.

The occurrence of 70 pharmaceutical and personal care products (PPCPs) was investigated in the Tone River. The river has the largest basin in Japan, and the water is utilized not only for farming, but also as a source of water supply. One day in both January and October 2006, surface waters in the river and its tributaries and effluents from sewage treatment plants (STPs) directly discharging into the Tone River were collected, the location of which ranged over 150 km along the river. The 70 PPCPs in the samples were concentrated by solid phase cartridge and were measured by LC-MS/MS using three analytical methods. Fifty-seven PPCPs were detected in one or more samples. Bezafibrate, caffeine, carbamazepine, clarithromycin, crotamiton and sulpiride were frequently detected. Mass flow profiles of some PPCPs (e.g., crotamiton) were comparable to cumulative inhabitants in the basin, suggesting that these PPCPs could be markers of population. Total load of each PPCP into the basin from upstream, the tributaries, and the STPs were calculated. The contribution of selected PPCPs from the tributaries with lower sewerage system coverage was dominant compared to those from upstream and the STPs, suggesting the installation of sewerage systems is necessary to reduce the load of PPCPs in the Tone River basin.