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Micrometam C is a core of novel marine compound isolated from the mangrove associates Micromelum falcatum. In this study, we investigated the protective effects of micrometam C in inflammation models in the transgenic zebrafish line Tg (corola: eGFP) and RAW264.7 macrophages. We found that micrometam C significantly suppressed the migration of immune cells in tail-cutting-induced inflammation in transgenic zebrafish and reduced lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) in both zebrafish and macrophages. In addition, micrometam C also restored LPS-induced reduction of endogenous antioxidants, such as catalase (CAT), glutathione (GSH) and superoxide dismutase (SOD). The protective effects of micrometam C were in parallel to its inhibition of NADPH oxidase and nuclear factor-kappa-binding (NF-κB) activity. Thus, the present results demonstrate that micrometam C protects against LPS-induced inflammation possibly through its antioxidant property. [ABSTRACT FROM AUTHOR]

Aims The miR-9 family microRNAs (miRNAs) are tumour suppressor miRNAs implicated in carcinogenesis. We postulated that miR-9-1, miR-9-2 and miR-9-3 may be inactivated by aberrant promoter methylation in multiple myeloma (MM). Methods Methylation of miR-9-1, miR-9-2 and miR-9- 3 was studied by methylation-specific PCR (MSP) in six normal controls, including three each of healthy peripheral blood (PB) or bone marrow buffy coat, 10 MM cell lines, 62 primary MM marrow samples at diagnosis and 22 at relapse/progression. Results MSP, verified by quantitative pyrosequencing, showed that the promoters of miR-9-3 and miR-9-1 were unmethylated in normal controls but methylated in 4 (40%) and 5 (50%) of 10 MM cell lines, respectively. However, the promoter of miR-9-2 was methylated in three normal PB buffy coat controls and in CD138-sorted healthy marrow plasma cells, indicating possibly tissue specific rather than tumour-specific methylation of miR- 9-2, which was thus not studied further. In WL-2 cells, which were completely methylated for miR-9-3, 5-aza- 20-deoxycytidine treatment caused miR-9-3 promoter demethylation and pri-miR-9-3 re-expression. In primary samples, methylation of miR-9-3 was detected in 1 of 62 patients at diagnosis and 1 of 22 patients at relapse/ progression. However, miR-9-1 methylation was absent in both primary samples at diagnosis and at relapse/ progression. Conclusions Hypermethylation of miR-9-3 and miR-9- 1 is tumour-specific in MM, leading to reversible miRNA silencing. Frequent methylation of miR-9-3 and miR-9-1 in cell lines, but not in primary samples, may be acquired during in vitro culture, and indicates an unimportant role of miR-9 methylation in myelomagenesis. [ABSTRACT FROM AUTHOR]

Besides carbon solubility, the carbide formation possibility is another important factor to differentiate various substrate materials in graphene growth. A recent experiment indicates that the formation of transition metal carbides (TMCs) can suppress carbon precipitation. In this study, Mo2C, a representative of TMCs, is used to study the effects of carbide formation in graphene growth from first principles. Carbon diffusion in Mo2C bulk turns out to be very difficult and it becomes much easier on the Mo2C(001) surface. Therefore, carbon precipitation suppression and graphene growth can be realized simultaneously. A direction depended diffusion behavior is observed on the Mo2C(101) surface, which makes it less favorable for graphene growth compared to the (001) surface. [ABSTRACT FROM AUTHOR]

In this paper, a composite buffer layer structure (CBLS) with multiple AlGaN layers and grading of Al composition/u-GaN1/(AlN/GaN) superlattices/u-GaN2 and InAlGaN/AlGaN quaternary superlattices electron-blocking layers (QSLs-EBLs) are introduced into the epitaxial growth of InGaN-based light-emitting diodes (LEDs) on 6-inch Si (111) substrates to suppress cracking and improve the crystalline quality and emission efficiency. The effect of CBLS and QSLs-EBL on the crystalline quality and emission efficiency of InGaN-based LEDs on Si substrates was studied in detail. Optical microscopic images revealed the absence of cracks and Ga melt-back etching. The atomic force microscopy images exhibited that the root-mean-square value of the surface morphology was only 0.82 nm. The full widths at half maxima of the (0002) and (101̅2) reflections in the double crystal X-ray rocking curve were ~330 and 450 respectively. The total threading dislocation density, revealed by transmission electron microscopy, was <; 6× 108 cm-2. From the material characterizations, described above, blue and white LEDs emitters were fabricated using the epiwafers of InGaN-based LEDs on 6-inch Si substrates. The blue LEDs emitter that comprised blue LEDs chip and clear lenses had an emission power of 490 mW at 350 mA, a wall-plug efficiency of 45% at 350 mA, and an efficiency droop of 80%. The white LEDs emitter that comprised blue LEDs chip and yellow phosphor had an emission efficiency of ~110 lm/W at 350 mA and an efficiency droop of 78%. These results imply that the use of a CBLS and QSLs-EBL was found to be very simple and effective in fabricating high-efficiency InGaN-based LEDs on Si for solid-state lighting applications. [ABSTRACT FROM AUTHOR]

Background Tree bark of Eucommia ulmoides Oliv., (commonly well-known as “Du-zhong” in China), has been used to treat hypertension, hypercholesterolemia, hyperglycemia, hepatic fibrosis and renal injury. This study aims to investigate the effects of lignans extracted from the bark of Eucommia ulmoides Oliv. on Ang II-induced proliferation and extracellular matrix biosynthesis in rat mesangial cells. Methods Rat mesangial cells (RMCs) were cultured in vitro and divided into six groups (control, Ang II, losartan, and low, middle and high concentration lignans groups). RMC proliferation was measured by MTT assay. RT-qPCR and western blotting were used to detect mRNA and protein expression of collagen type I (Col I), collagen type III (Col III), collagen type IV (Col IV), fibronectin and aldose reductase (AR). Results Cellular proliferation induced by Ang II was significantly suppressed by Eucommia lignans of different concentrations (P = 0.034, P < 0.001, and P < 0.001). Treatment of cells with Ang II increased Col I, Col III, Col IV, and fibronectin mRNA expression, which was observed at the protein level (P < 0.001, P < 0.001, P = 0.004, and P = 0.004, respectively). The increased mRNA expression and protein levels of Col I, Col III, Col IV, and fibronectin were diminished remarkably with by treatment Eucommia lignans, and elevated AR expression stimulated by Ang II was significantly inhibited by Eucommia lignans. Conclusions Eucommia lignans (Du-zhong) inhibited Ang II-stimulated extracellular matrix biosynthesis in mesangial cells. [ABSTRACT FROM AUTHOR]

The lignan extracts from the tree bark of Eucommia ulmoides Oliv., a famons traditional Chinese medicine, have been demonstrated to have inhibitory effects on aldose reductase activity in spontaneously hypertensive rat myocardium. This study was aimed to investigate the hypertensive cardiac remodeling effects of the lignan extracts together with epalrestat. Ten-week-old male spontaneously hypertensive rats were randomly divided into three groups (n = 12, each) and administered 100 mg/kg/d of captopril (angiotensin converting enzyme inhibitor), 100mg/kg/d of epalrestat (aldose reductase inhibitor) or 300mg/kg/d of lignan extracts by gavage for 16 weeks. Sex-, age-, and number-matched normotensive Wistar Kyoto rats with spontaneously hypertensive rats were treated with distilled water (vehicle) as controls. Systolic blood pressures were measured periodically. Echocardiography examination was taken when rats were 24 weeks old. We found that both captopril and lignan extracts lowered blood pressure, and inhibited aldose reductase activity similarly to epalrestat. Echocardiography examination and histomorphometry indices were improved in all treated groups (p < 0.05). Therefore, lignan extracts could prevent hypertensive cardiac remodeling, which is likely related to aldose reductase inhibition. [ABSTRACT FROM AUTHOR]

Janus kinase 2 (JAK2) is an important mediator of cytokine receptor signaling and plays key roles in hematopoietic and immune responses. The acquired JAK2 R683G(S) somatic mutations are detected in 15% of patients with B-cell acute lymphoblastic leukemia (B-ALL) and are presumed to be a biomarker for B-ALL. However, how JAK2 R683G(S) mutations lead to B-ALL is still unclear. Our results indicated that the E627 and R683 interaction played a vital role in JAK2 autoinhibition. Mutations (R683S, R683G and E627A) disrupting this interaction led to JAK2 constitutive activation, while mutations (R683K, E627D) restoring this interaction decreased its activity. Furthermore, spectroscopy experiments implied that disruption of the E627 and R683 interaction abolished JH1/JH2 domain interactions and forced the JH1 domain into the open, active conformation. Mutations abolishing this interaction promoted the proliferation of Ba/F3 cells. The results herein may provide clues to understanding the mechanism of JAK2 R683G(S) mutation-associated B-ALL. [ABSTRACT FROM AUTHOR]

Tetrabutylammonium 4-(2-bromothiophene-5-sulfanilamide)-benzoate crystallizes in C lattice with a = 18.3389(17), b = 16.540(16), c = 15.8280(15) Å, β = 116.959(2), V = 4279.5(7) Å, Z = 4, and R = 0.0560. In the structure a very short centrosymmetric hydrogen bond and C=O···Br halogen bond interactions, together with N–H···O and C–H···O hydrogen bonds give a three-dimensional network. Graphical Abstract: A extremely short O–H···O hydrogen bond is observed between the two neighboring 4-(2-bromothiophene-5-sulfanilamide)-benzoates. The H atom is fixed at the crystallographic inversion center and bridges the two benzoates to form an anion dimer. Halogen bonds also aid in forming the interest structure in crystal.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The phylogenetic placement of the Old World Gesneriaceae genera Ramonda, Conandron, Bournea, Thamnocharis, and Tengia, all characterized by actinomorphic flowers, has been the subject of much debate. Actinornorphy in Gesneriaceae is rare, with most species exhibiting zygomorphic flowers. The actinomorphic genera have historically been considered "primitive" and lumped in the tribe Ramondeae separate from the remaining Old World Gesneriaceae. In this study, we used nuclear (ITS) and plastid (trnL-F) DNA for molecular phylogenetic analysis of these five genera along with representative species across the Cyrtandroideae. Our results show that the actinomorphic genera are scattered over several otherwise zygomorphic clades within Cyrtandroideae, and along with previous data, indicate that Ramondeae is an unnatural group. Floral actinomorphy has evolved convergently in different alliances of Old World Gesneriaceae. Ramonda is sister to I-faber/ca, Bournea is apparently paraphyletic, Conandron seems rather isolated, and Tengia is close to Petrocodon and sister to a group of Chirita sect. Gibbosaccus together with Calcareoboea. We hypothesize that the evolution from zygomorphy to actinomorphy with novel combinations of characters is possibly due to shifts in pollination strategies, such as a switch from nectarto pollen-rewards. [ABSTRACT FROM AUTHOR]

Gallium-doped ZnO films were grown on p-Si(111) substrates by atmospheric pressure metal-organic chemical vapor deposition (AP-MOCVD) using diethylzinc and water as reactant gases and triethyl gallium (TEG) as a n-type dopant gas. The structural, electrical, and optical properties of ZnO:Ga films obtained by varying the flow rate of TEG from 0.56 to 3.35 μmol/min were examined. X-ray diffraction patterns and scanning electron microscopy images indicated that Ga doping plays a role in forming microstructures in ZnO films. A flat surface with a predominant orientation (101) was obtained for the ZnO:Ga film fabricated at a flow rate of TEG=2.79 μmol/min. This film also revealed a lowest resistivity of 4.54×10-4 Ω cm, as measured using the van der Pauw method. Moreover, low temperature photoluminescence (PL) emission recorded at 12 K demonstrated the Burstein Moss shift of PL line from 3.365 to 3.403 eV and a line broadening from 100 to 165 meV as the TEG flow rate varied from 0.56 to 2.79 μmol/min. This blueshift behavior of PL spectra from ZnO:Ga films features the degeneracy of semiconductor, which helps to recognize the enhancing of transparency and conductivity of ZnO films fabricated by AP-MOCVD using Ga-doping technique. [ABSTRACT FROM AUTHOR]

In this paper, we report the fabrication of an In0.2Ga0.8N/GaN multiple-quantum-well (MQW) structure on vicinal sapphire substrates with a very small offset angle of 0-1° by low-pressure metallorganic chemical vapor deposition. Our study demonstrates that the quality of the In0.2Ga0.8N/GaN MQW structure is very sensitive to the offset angle of the vicinal substrate. High-resolution X-ray diffraction analyses demonstrated high-order satellite peaks and clear fringes between them for all MQW structures fabricated, from which the interface roughness (IRN) was estimated. The IRN of the In0.2Ga0.8N/GaN MQW structure fabricated on 0.2° off sapphire substrate was determined as 1.36% of the quantum well layer period. Besides, reciprocal lattice mapping was employed to examine the strain status of the MQW. The lattice relaxation of the same specimen mentioned above was estimated to be 7.4 X 10-5. It is therefore manifested that an In0.2Ga0.8N/GaN MQW structure with abrupt interfaces and good layer periodicity was grown. From it, a shortest radiative lifetime of 14.2 as and a lowest fluctuation of 5.6 meV in the emission energy of micro-photoluminescence mapping were achieved. In addition, superior material qualities of the whole film fabricated on 0.2° off substrate were recognized by cross-sectional transmission electron microscopy. Based on the results mentioned above, a high-quality In0.2Ga0.8N/GaN MQW blue light, emitting diode (LED) has been fabricated on 0.2° off substrate, which demonstrated a strong room-temperature electroluminescence emission at the wavelength of 465 nm and with the full width at half maximum of only 19 nm. The same device also showed an output power of 13.4 mW and an external quantum efficiency of 19.2%. Both these characteristics are improved drastically compared with the devices fabricated on the substrates with other offset angles. Conclusively, the use of an appropriately misoriented sapphire substrate is suggested to be effective for elevating the emission efficiency of In0.2Ga0.8N/GaN MQW blue LED fabricated thereon. [ABSTRACT FROM AUTHOR]

Well-aligned good-quality carbon nanotube (CNT) array was grown on silicon substrate by atmospheric pressure chemical vapor deposition (APCVD) through SiO2 masking. First, the patterned substrate was pretreated with NH3 and then CNTs were synthesized at 800 °C using Ni as the catalyst, acetylene (C2H2) as the carbon source material and N2 as the carrier gas. Effects of the NH3-pretreatment time, the flow ratio of [C2H2]/[NH3] and the CNT growth time on the qualities of CNT array were analyzed in detail. It was found that good-quality CNTs with an average length of around 15 μm could be grown by pretreating the Si substrate with NH3 for 10 min and then conducting the CNT growth with a flow ratio of [C2H2]/[NH3] = 30/100. Furthermore, the field emission property of CNT array was investigated using a diode structure. It was found that the turn-on electric field decreased with increasing CNT length. The turn-on electric field as low as about 2 V/μm with an emission current density of 10 μA/cm2 was achieved for a CNT-array diode with the tube length near 18 μm. For the same device, the emission current density could be elevated to 10 mA/cm2 with the applied voltage of 3.26 V/μm. [ABSTRACT FROM AUTHOR]

A new species of Gesneriaceae, Chirita maguanensis Z.Y.Li, H.Jiang & H.Xu, is described from Southern Yunnan, China. It is similar to C. eburnea Hance in its large, fleshy, white and parallel-veined bracts, but differs by having broad and oblique leaves with a repand–crenate or crenate margin, suborbicular bracts, membranous, white calyx, purple corolla-tube, 2-parted lower lip of stigma and lower disc. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 269–273. [ABSTRACT FROM AUTHOR]

Indium nitride (InN) epilayers have been successfully grown on Si (111) substrates with low-temperature (450 °C) grown InN and high-temperature (1050 °C) grown AlN (InN/AlN) double-buffer layers by atmospheric-pressure metal-organic chemical vapor deposition (AP-MOCVD). X-ray diffraction characterizations indicated that highly (0001)-oriented hexagonal InN was grown on Si (111) substrate. Photoluminescence (PL) analyses performed at room temperature showed a strong emission at 0.72 eV with a full width at half maximum of 121 meV. Excitation intensity dependent measurements demonstrated the PL mechanism to be the band-to-band transition. Time-resolved PL could be fitted by a single exponential exhibiting an ordered film and a recombination lifetime of around 0.85 ns. In particular, transmission electron microscopy characterizations indicated that the use of AlN first buffer is very important to achieve a structurally uniform (0001)-oriented InN epilayer on Si (111) by AP-MOCVD. [ABSTRACT FROM AUTHOR]

Five new polycyclic Daphniphyllum alkaloids, macropodumines F (1) and G (2), 17-oxoyuzurimine (3), and macropodumines H (4) and I (5), were isolated from the leaves of D. macropodumMiq., collected in Sichuan Province, China. The structures and relative configurations of the new compounds – as well as of four known, related alkaloids – were elucidated on the basis of in-depth spectroscopic and mass-spectrometric analyses, by chemical derivatization, and by comparison of spectroscopic data with those of known compounds. [ABSTRACT FROM AUTHOR]