[UPLC-Q-TOF-MS-based metabolomics reveals mechanism of Morinda officinalis iridoid glycosides in treating rheumatoid arthritis and bone loss].

This study aimed to investigate the therapeutic effects of Morinda officinalis iridoid glycosides(MOIG) on paw edema and bone loss of rheumatoid arthritis(RA) rats, and analyze its potential mechanism based on ultra-high performance liguid chromatography-guadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS) serum metabolomics. RA rats were established by injecting bovin type Ⅱ collagen. The collagen-induced arthritis(CIA) rats were administered drug by gavage for 8 weeks, the arthritic score were used to evaluate the severity of paw edem, serum bone metabolism biochemical parameters were measured by ELISA kits, Masson staining was used to observe the bone microstructure of the femur in CIA rats. UPLC-Q-TOF-MS was used to analyze the alteration of serum metabolite of CIA rats, principal component analysis(PCA) and partial least squares-discriminant analysis(PLS-DA) were used to screen the potential biomarkers, KEGG database analysis were used to construct related metabolic pathways. The results demonstrated that the arthritic score, serum levels of IL-6 and parameters related with bone metabolism including OCN, CTX-Ⅰ, DPD and TRAP were significantly increased, and the ratio of OPG and RANKL was significantly decreased, the microstructure of bone tissue and cartilage were destructed in CIA rats, while MOIG treatments could significantly reduce arthritis score, mitigate the paw edema, reverse the changes of serum biochemical indicators related with bone metabolism, and improve the microstructure of bone tissue and cartilage of CIA rats. The non-targeted metabolomics results showed that 24 altered metabolites were identified in serum of CIA rats; compared with normal group, 13 significantly altered metabolites related to RA were identified in serum of CIA rats, mainly involving alanine, aspartate and glutamate metabolism; compared with CIA model group, MOIG treatment reversed the alteration of 15 differential metabolites, mainly involving into alanine, aspartate and glutamate metabolism, D-glutamine and D-glutamate metabolism, taurine and hypotaurine metabolism, valine, leucine and isoleucine biosynthesis. Therefore, MOIG significantly alleviated paw edema, improved the destruction of microstructure of bone and cartilage in CIA rats maybe through involving into the regulation of amino acid metabolism.

Self-Q-switched, orthogonally polarized, dual-wavelength laser using long-lifetime Yb³âº crystal as both gain medium and saturable absorber.

A novel self-Q-switched and orthogonally polarized dual-wavelength laser has been investigated with Yb³âº-doped CGB disordered crystals. By slightly inclining output coupler to introduce the Fresnel loss, we realized simultaneously dual-wavelength laser operation at 1052.6 nm in E//b polarization and 1057.7 nm in E//c polarization with a frequency difference of 1.38 THz. Self-Q-switched pulse generation was observed in this free-running laser, originating from the nonlinear reabsorption effect of Yb:CGB as well as the strong storage of inversion population induced by the long excited-state lifetime (~1 ms). Pulse duration of 287 ns was obtained with an output average power of 416 mW and a repetition rate of 35 kHz. The self-Q-switching effect increased the peak power by 100 times the average power. This very simple laser, free from the complexity and high-cost of additional intracavity polarization modulator and Q-switcher, may be applied for constructing miniature, integrated and portable laser system.

[Studies on fluorescence spectral characteristics of fulvic acid (FA) from Xingkai Lake sediments].

Four samples (sample No. HXXD, HXXX, HXDX and HXDB) were taken from Xingkai Lake Sediments in Heilongjiang province and fluorescence spectral characteristics of Fulvic acid (FA) from sediments were studied. Conventional and excitation-emission matrix (EEM) all indicated that FA from HXXD sediment exhibited primary peaks at longer wavelengths. The analysis of fluorescence characteristic parameters indicated that the degree of humification of FA from all sample points were in the order: HXXD > HXDX > HXDB > HXXX. Fluorescence index (f450/500) suggested that FA from HXXD mainly originated from terrestrial sources, while the FA from other samples mainly originated from aquatic organism sources and terrestrial sources. Based on EEM fluorescence regional integration (FIR), the percent fluorescence responses (P(i, n)) of five regions in 3EEMs was calculated. The distributions of P(V, n) (humic acid-like region) and P(III, n) (fulvic acid-like region) were the largest in all samples. The conclusion of the degree of humification of FA based on FIR was consistent with the analysis of conventional fluorescence parameters. The correlation analysis showed that, gamma(A, C) was significantly correlative with P(V, n)/P(III, n), (P(V, n) + P(III, n))/(P(I, n) + P(II, n) + P(III, n)) and P(V, n). The results suggest that gamma(A, C) index is a reasonable tool for assessing humification degree of FA from Xingkai Lake sediments.

[Effects of staged acupuncture on endometrial receptivity and anxiety in patients with recurrent implantation failure of thin endometrium based on "thoroughfare vessel is the sea of blood" theory].

OBJECTIVE: To compare the clinical efficacy between staged acupuncture based on "thoroughfare vessel is the sea of blood" theory combined with routine hormone replacement cycle treatment and routine hormone replacement cycle treatment for patients with recurrent implantation failure (RIF) of thin endometrium. METHODS: A total of 72 RIF patients with thin endometrium were randomly divided into an observation group and a control group, 36 cases in each group. The patients in the control group were treated with routine hormone replacement cycle treatment. Based on the treatment of the control group, the patients in the observation group were treated with staged acupuncture based on "thoroughfare vessel is the sea of blood" theory. The main acupoints were Neiguan (PC 6) and Gongsun (SP 4), and the supplementary acupoints were selected according to the menstrual cycle and syndrome differentiation; the acupuncture was given once every other day, 3 times a week, for 3 consecutive menstrual cycles. The thickness and shape of endometrium, and Hamilton anxiety scale (HAMA) score were observed at implantation window before and after treatment; the clinical pregnancy rate, live birth rate and cycle cancellation rate were compared between the two groups; the correlation between endometrial thickness and HAMA score was analyzed. RESULTS: Compared before treatment, the endometrial thickness in the two groups and the proportion of type A+B endometrium in the observation group were increased (P<0.05), and the HAMA scores in the two groups were decreased (P<0.05) after treatment. The above indexes in the observation group were superior to those in the control group (P<0.05). The clinical pregnancy rate and live birth rate in the observation group were higher than those in the control group (P<0.05), and the cycle cancellation rate was lower than that in the control group (P<0.05). There was a negative correlation between endometrial thickness and HAMA score (P<0.05). CONCLUSION: Based on the routine hormone replacement cycle treatment, the addition use of staged acupuncture based on "thoroughfare vessel is the sea of blood" theory could improve the thickness and shape of endometrium, relieve anxiety, increase the clinical pregnancy rate and live birth rate, and reduce the cycle cancellation rate in RIF patients with thin endometrium. The curative effect is superior to the routine hormone replacement cycle treatment alone.

Efficient graphene Q switching and mode locking of 1.34 µm neodymium lasers.

We demonstrate that few-layered graphene sheets used as a saturable absorber can provide efficient Q-switching and mode-locking modulation in 1.34 µm Nd:GdVO(4) bulk lasers. The minimum Q-switched pulses were 450 ns for 260 mW average power, 43 kHz repetition rate, and 2.5 µJ pulse energy. For the mode-locked laser, an average power of 1.29 W was achieved with 11 ps pulse duration and 13 nJ pulse energy. To our knowledge, this average power is the highest yet obtained from a graphene mode-locked laser, and the corresponding optical-optical efficiency of 23% is the best result among 1.3 µm neodymium mode-locked lasers. The quality factor M(2) of the Q-switched beam was 1.4 and 1.6 in the horizontal and longitudinal planes, respectively, and the M(2) of the mode-locked beam reached 1.1 and 1.0. These results clearly indicate the advantages of few-layered graphene as a saturable absorber.

Large energy laser pulses with high repetition rate by graphene Q-switched solid-state laser.

We demonstrated that the graphene could be used as an effective saturable absorber for Q-switched solid-state lasers. A graphene saturable absorber mirror was fabricated with large and high-quality graphene sheets deprived from the liquid phase exfoliation. Using this mirror, 105-ns pulses and 2.3-W average output power are obtained from a passively Q-switched Nd:GdVO(4) laser. The maximum pulse energy is 3.2 µJ. The slope efficiency is as high as 37% approximating to 40% of the continue-wave laser, indicating a low intrinsic loss of the graphene.

Graphene saturable absorber mirror for ultra-fast-pulse solid-state laser.

High-quality graphene sheets with lateral size over 20 µm have been obtained by bath sonicating after subjecting the wormlike graphite marginally to mixed oxidizer. To date, to our knowledge, they are the largest graphene sheets prepared by exfoliation in the liquid phase. A saturable absorber mirror was fabricated based on these sheets. We exploited it to realize mode-locking operation in a diode-pumped Nd:GdVO(4) laser. A pulse duration of 16 ps was produced with an average power of 360 mW and a highest pulse energy of 8.4 nJ for a graphene mode-locked laser.

Diode-pumped passively mode-locked Nd:YAG laser at 1338 nm with a semiconductor saturable absorber mirror.

We demonstrate a diode-end-pumped passively mode-locked 1338 nm Nd:YAG laser with a semiconductor saturable absorber mirror. At the absorbed pump power of 8.89 W, an average output power of 1.12 W was obtained with a slope efficiency of 14%. The pulse width was 22.4 ps with a repetition rate of 63.9 MHz, corresponding to a peak power of 782 W. In addition, the bandwidth of the mode-locking spectrum is as narrow as 20.44 GHz, which shows the potential application in long-distance ranging and fiber information transmission because of the low dispersion of these ultrashort pulses.

V3+:YAG as the saturable absorber for a diode-pumped quasi-three-level dual-wavelength Nd:GGG laser.

The performance of a diode-end-pumped passively Q-switched dual-wavelength Nd:GGG laser operating at 932.9 and 936.5 nm with V(3+):YAG as the saturable absorber was demonstrated for the first time to the best of our knowledge. The maximum dual-wavelength average output power of 150 mW was achieved with a T = 2% output coupler under the absorbed pump power of 2.55 W, corresponding to the optical-to-optical conversion and slope efficiency of 5.9% and 8.0%, respectively. The minimum pulse width was 395 ns with the pulse repetition frequency of 140 kHz, which was attained with a T = 5% output coupler under the absorbed pump power of 2.55 W.

Diode-pumped passively Q-switched Nd:Gd0.5Y0.5VO4 laser at 1.34 microm with V3+:YAG as the saturable absorber.

The performance of a diode-pumped passively Q-switched Nd:Gd(0.5)Y(0.5)VO(4) laser at 1.34 microm with V(3+):YAG as the saturable absorber was demonstrated for the first time to the best of our knowledge. The focal lengths of thermal lens in the diode-end-pumped Nd:Gd(0.5)Y(0.5)VO(4) laser for the 1.34 microm transition was experimentally investigated, with the corresponding proportion constant estimated to be approximately1.5x10(4) W/mm. For the passive Q-switching operation, the maximum average output power of 0.96 W was achieved under the pump power of 7.28 W, corresponding to optical-to-optical conversion and slope efficiency of 13.2% and 17.6%, respectively. The minimum pulse width attained was 47.8 ns with the pulse repetition frequency of 76 kHz, with the single pulse energy and peak power estimated to be 8.7 microJ and 182 W, respectively.

Structure Elucidation of a Polysaccharide from Umbilicaria esculenta and Its Immunostimulatory Activity.

Umbilicaria esculenta has been used as a tonic food in China for several centuries owing to its pleasant flavor and health benefits. In this study, a water soluble polysaccharide, which we designated as UP2, with an average molecular weight of 3.33 × 105 Da, was isolated from U. esculenta cultivated in the Huangshan Mountain, by consecutive hot water extraction and anion-exchange chromatography. Gas chromatography analysis indicated that UP2 contained three kinds of monosaccharides, including mannose, glucose, and galactose at a molar ratio of 1.7:1.0:1.2. Linkage analysis of UP2 revealed the presence of (1 → 6)-linked glucosyl, (1 → 3,6)-linked glucosyl, t-linked galactosyl, (1 → 6)-linked galactosyl and (1 → 6)-linked mannosyl at a molar ratio of 0.7:4.6:4.1:2.2:9.1. Structural analysis determined that UP2 possessed a backbone consisting of (1 → 6)-linked ß-D-glucopyranosyl and (1 → 6)-linked α-D-mannopyranosyl residues, which substituted at the O-3 position of (1 → 6)-linked ß-D-glucopyranosyl residues by branches of (1 → 6)-linked α-D-galactopyranosyl and 1-linked ß-D-galactopyranosyl residues. Immunostimulatory activity analysis showed that UP2 could stimulate the proliferation of RAW264.7 cells in a dose-dependent manner, and all the samples (20-500 µg/mL) were found to enhance nitric oxide production. The highest phagocytic activity of UP2 was observed at 200 µg/mL. Thus, UP2 may be a potential source of biological and pharmacological agents.

Rheological properties of a polysaccharide from floral mushrooms cultivated in Huangshan Mountain.

A polysaccharide fraction (FMPS) was isolated from floral mushrooms cultivated in Huangshan Mountain, and the rheological properties of FMPS in aqueous solutions were investigated. The FMPS solution showed shear-thinning behavior at 25°C. Dynamic viscoelastic tests revealed that G' and G″ exhibited strong dependences on the concentration and temperature. The FMPS/water system exhibited sol and weak gel behavior with the change of concentration and temperature. The exponent n of G'∼ω(n) and tan δ also exhibited strong dependences on the concentration and temperature. The gel point (cgel) of FMPS solution was 1.16×10(-2)g/mL at 15°C, and the Tgel of 1.4×10(-2)g/mL FMPS solution was 20.6°C. Dynamic frequency sweep measurements indicated that the FMPS gel system was stable in the selected range of frequency. The heating-cooling process proved that the sol-gel transition of FMPS in aqueous solutions was thermally reversible.

Physicochemical properties and antioxidant activities of polysaccharide from floral mushroom cultivated in Huangshan Mountain.

In this paper, a polysaccharide fraction (FMPS) was purified from the floral mushroom cultivated in Huangshan Mountain for the first time. Physicochemical properties and antioxidant activities of FMPS were investigated. FMPS had an average molecular weight of 7.2×10(5)Da and was composed of glucose. On the basis of FT-IR, NMR and methylation analysis, the repeating unit of FMPS was established as (1→3)-linked ß-d-glucopyranosyl backbone with 1-linked ß-d-glucopyranosyl branches substituted at O-6 position of (1→3)-linked ß-d-glucopyranosyl residues. The advanced structure studies indicated that FMPS was a triple-helical polysaccharide. The main hydrodynamic radius (Rh) of FMPS was 23.4nm and it could form a stable system with water in 1.2×10(-2)g/mL solutions. In addition, FMPS exhibited high DPPH radical scavenging activities (79.46% at 5mg/mL) and hydroxyl radical scavenging activities (74.18% at 5mg/mL), as well as Fe(2+)chelating activities and ABTS radical scavenging activities to some extent.

Ultrasensitive nonlinear absorption response of large-size topological insulator and application in low-threshold bulk pulsed lasers.

Dirac-like topological insulators have attracted strong interest in optoelectronic application because of their unusual and startling properties. Here we report for the first time that the pure topological insulator Bi2Te3 exhibited a naturally ultrasensitive nonlinear absorption response to photoexcitation. The Bi2Te3 sheets with lateral size up to a few micrometers showed extremely low saturation absorption intensities of only 1.1 W/cm(2) at 1.0 and 1.3 µm, respectively. Benefiting from this sensitive response, a Q-switching pulsed laser was achieved in a 1.0 µm Nd:YVO4 laser where the threshold absorbed pump power was only 31 mW. This is the lowest threshold in Q-switched solid-state bulk lasers to the best of our knowledge. A pulse duration of 97 ns was observed with an average power of 26.1 mW. A Q-switched laser at 1.3 µm was also realized with a pulse duration as short as 93 ns. Moreover, the mode locking operation was demonstrated. These results strongly exhibit that Bi2Te3 is a promising optical device for constructing broadband, miniature and integrated high-energy pulsed laser systems with low power consumption. Our work clearly points out a significantly potential avenue for the development of two-dimensional-material-based broadband ultrasensitive photodetector and other optoelectronic devices.