Dynamically tunable vortex four-wave mixing in a six-level system.

We investigate the orbital angular momentum of vortex light in a six-level atomic system with a closed loop. We find that a vortex light field via four-wave mixing (FWM) is sensitive to the relative phase of the driving fields due to forming a closed loop configuration. Thus, it could periodically tune the phase and intensity of the vortex FWM field by adjusting the relative phase of the driving fields. Moreover, the spatial modulation of the vortex FWM phase and intensity also can be achieved by tuning the intensity of the microwave field and detuning of the driving fields.

Pressure-Induced Phase Transition in Weyl Semimetallic WTe2.

Tungsten ditelluride (WTe2 ) is a semimetal with orthorhombic Td phase that possesses some unique properties such as Weyl semimetal states, pressure-induced superconductivity, and giant magnetoresistance. Here, the high-pressure properties of WTe2 single crystals are investigated by Raman microspectroscopy and ab initio calculations. WTe2 shows strong plane-parallel/plane-vertical vibrational anisotropy, stemming from its intrinsic Raman tensor. Under pressure, the Raman peaks at ≈120 cm-1 exhibit redshift, indicating structural instability of the orthorhombic Td phase. WTe2 undergoes a phase transition to a monoclinic T' phase at 8 GPa, where the Weyl states vanish in the new T' phase due to the presence of inversion symmetry. Such Td to T' phase transition provides a feasible method to achieve Weyl state switching in a single material without doping. The new T' phase also coincides with the appearance of superconductivity reported in the literature.

[Effect on Fermi Resonance by Some External Fields: Investigation of Fermi Resonance According to Raman Spectra].

Fermi resonance is a phenomenon of molecular vibrational coupling and energy transfer occurred between different groups of a single molecule or neighboring molecules. Many properties of Fermi resonance under different external fields, the investigation method of Raman spectroscopy as well as the application of Fermi resonance, etc need to be developed and extended further. In this article the research results and development about Fermi resonance obtained by Raman spectral technique were introduced systematically according to our work and the results by other researchers. Especially, the results of the behaviors of intramolecular and intermolecular Fermi resonance of some molecules under some external fields such as molecular field, pressure field and temperature field, etc were investigated and demonstrated in detail according to the Raman spectra obtained by high pressure DAC technique, temperature variation technique as well as the methods we planed originally in our group such as solution concentration variation method and LCOF resonance Raman spectroscopic technique, and some novel properties of Fermi resonance were found firstly. Concretely, (1) Under molecular field. a. The Raman spectra of C5H5 N in CH3 OH and H2O indicates that solvent effect can influence Fermi resonance distinctly; b. The phenomena of the asymmetric movement of the Fermi resonance doublets as well as the fundamental involved is tuned by the Fermi resonance which had not been found by other methods were found firstly by our variation solution concentration method; c. The Fermi resonance properties can be influenced distinctly by the molecular group reorganization induced by the hydrogen bond and anti-hydrogen bond in solution; d. Fermi resonance can occurred between C7 H8 and m-C8H10, and the Fermi resonance properties behave quite differently with the solution concentration; (2) Under pressure field. a. The spectral lines shift towards high wavenumber with increasing pressure, and frequency difference Δ varies with pressure, which induced the change of W; b. The W of νi + ν4 ν3 of CCl4 in C6H6 decreased more quickly in solution than in pure liquid with increasing pressure and the Fermi resonance disappeared ahead of that in pure liquid, which indicates that the phenomenon of Fermi resonance induced by pressure effect can reveal the mechanism of some solvent effects. (3) Under temperature field. a. The Fermi resonance properties of different molecules behave quite differently with temperature. For an instance, the one of CO2 can be influenced distinctly by temperature, while the one of CS2 behaves no change with temperature. This article offers systematic theoretical and experimental support to the investigation of identification and assignment of molecular spectral line, the confirmation of molecular conformation and conformers, the effect of hydrogen bond on molecular structure and properties, etc.

Chinese medicine formula lingguizhugan decoction improves Beta-oxidation and metabolism of Fatty Acid in high-fat-diet-induced rat model of Fatty liver disease.

Lingguizhugan decoction (LGZG), a classic traditional Chinese medicine (TCM) formula, has been used to treat obesity and hyperlipidemia in recent years, but the related mechanisms underlying the regulation of lipid metabolism by LGZG are not clear yet. Here, we reported the effectiveness and possible mechanisms of LGZG on rats with fatty liver disease induced by high-fat diet (HFD). Our results demonstrated that LGZG significantly attenuated HFD-induced fatty liver disease, as measured by body weight, liver index, epididymal fat pad-body weight ratio (EFP/BW), liver injury, and hepatic triglycerides (TG) probably through increasing serum thyroid hormone levels, improving beta-oxidation (via modulation of TR ß 1 and CPT1A expression), metabolism and transport (through modulation of SREBP-1c, ACSL and ApoB100 expression) of fatty acid. In addition, we discovered the herbal combination with the properties of warming yang to relieve water retention in the formula and proposed the biological basis of LGZG conventional effect via further study on disassembled formula. This study, for the first time, revealed the mechanisms through which LGZG regulates lipid metabolism. Furthermore, our study suggested that it might be feasible to understand the scientific implications of TCM from the perspective of classic formulas' conventional efficacy.

[Comparative study on the effects of different therapeutic methods in preventing and treating nonalcoholic fatty liver in rats].

OBJECTIVE: To explore the pathogenesis of nonalcoholic fatty liver (NAFL) in traditional Chinese medicine (TCM) by comparing the therapeutic efficacy of methods for fortifying the spleen and replenishing qi, warming yang and fortifying the spleen and warming yang to move water. METHODS: Male Wistar rats were randomly divided into normal, model, Sijunzi Tang (SJZ), Lizhong Tang (LZ), Linggui Zhugan Tang (LGZG) and Shenzhuo Tang (SZ) groups. Rats in the normal group were fed with ordinary diet, while the rats in the other groups were fed with high fat diet including 88% ordinary food, 10% lard oil and 2% cholesterol. After four weeks of treatment, the weight of liver and epididymal fat was recorded respectively for calculating the indexes of liver (liver weight/body weight) and epididymal fat (weight of epididymal fat pads/body weight); the pathological changes in liver tissues were observed by hematoxylin and eosin (HE) staining; the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triacylglycerol (TAG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and very-low-density lipoprotein cholesterol (VLDL-C) and liver TAG concentration were analyzed by biochemical test. RESULTS: Body weight, liver and epididymal fat indexes and liver TAG level of rats all significantly increased in the model group as compared with the normal group (P<0.05). Hepatic fatty infiltration, TAG concentration and the levels of serum TAG and ALT were significantly decreased in the LGZG and SZ groups when compared to those in the model group (P<0.05). In addition, epididymal fat index and serum TC level also significantly decreased in the LGZG group as compared with the model group (P<0.05). However, there was no significant change in liver TAG concentration in LZ and model groups. CONCLUSION: Method of warming yang or moving water can promote the lipid metabolism. It may be an effective strategy in preventing and treating NAFL by treating with warming yang and moving water together.

[Effects of the mixture of Swertia pseudochinensis Hara and Silybum marianum Gaertn extracts on CCl(4)-induced liver injury in rats with non-alcoholic fatty liver disease].

OBJECTIVE: To study the mechanism of liver injury induced by carbon tetrachloride (CCl(4)) in rats with non-alcoholic fatty liver disease (NAFLD), and the therapeutic effects of the extract mixture of Dangyao (Swertia pseudochinensis Hara) and Shuifeiji (Silybum marianum Gaertn) on NAFLD rats with liver injury. METHODS: Male Wistar rats were randomized into normal control group, CCl(4) group, high-fat diet group, high-fat diet plus CCl(4) injection group (model group), diammonium glycyrrhizinate group and extract mixture group. Except the normal control and CCl(4) groups, rats were fed with high-fat diet (88% normal chow, 10% lard and 2% cholesterol) to induce NAFLD. Diammonium glycyrrhizinate and extracts were given by gavage. After eight weeks, a nonlethal dose of CCl(4) was injected intraperitoneally to all rats except the normal and high-fat diet groups. And 48 h later, all rats were sacrificed, and serum and liver tissues were collected for further study. Paraffin-processed liver tissue was stained with hematoxylin-eosin (HE) to observe the pathological changes. Serum alamine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The levels of triacylglycerol (TAG), malondialdehyde (MDA) and glutathione (GSH) in liver tissues were also examined. Expression of uncoupling protein 2 (UCP2) was determined by reverse transcription-polymerase chain reaction and Western blotting. RESULTS: Liver sections stained with HE showed that the histopathological changes in the normal control group and the CCl(4) group were mild; massive hepatosteatosis diffusing in lobules was shown in the high-fat diet groups; steatosis, hepatocellular ballooning degeneration and inflammatory infiltration were severe around the central vein in sections of the model group. Compared with the model group, hepatosteatosis and ballooning were significantly attenuated in the treatment groups. Levels of serum ALT and AST, contents of TAG and MDA and the UCP2 expression in liver tissues of the model group increased obviously, while the level of liver GSH decreased. Compared with rats in the model group, the above biomarkers in the treatment groups were improved significantly. CONCLUSION: The mixture of Dangyao and Shuifeiji extracts can decrease the susceptibility and degree of liver injury induced by hepatotoxin in rats with NAFLD. Regulation of the balance of pro- and anti-oxidative stress factors is involved in the mechanism.

The effect of the Fermi resonance on the Raman scattering cross sections of the Fermi doublet ν1 and 2ν2 of liquid carbon disulfide in benzene.

The effect of the Fermi resonance (FR) on the Raman scattering cross sections (RSCSs) of the Fermi doublet ν1, 2ν2 of liquid CS2 in C6H6 using the method of changing the volume concentration of the solution is investigated. We have calculated the RSCSs of the Fermi doublet ν1, 2ν2 using Onsager's theory with the 992 cm(-1) Raman line of C6H6 as the internal standard. The result shows that the RSCS of the ν1 line decreases with decreasing the volume concentration of CS2, while that of the 2ν2 line unexpectedly increases. With decreasing the volume concentration of CS2, two main effects of the solvent effect (SE) and the FR in binary solution that can make the ν1, 2ν2 RSCSs change: the SE, as calculated, reduces both the ν1 and 2ν2 RSCSs; the FR plays a significant role in reducing the ν1 RSCS and enhancing the 2ν2 RSCS. In comparison with our previous investigation [J. Raman Spectrosc. 41 (2010) 776-779], it was found that the stronger the FR is, the more the RSCS of the ν1 decreases and the 2ν2 increases. Thus, we proposed that the result can be best explained by taking into account the effect of the FR on the RSCSs of the Fermi doublet. In addition, this paper also gives an explanation to the experimental results deviating from the theoretical results of the scattering coefficients of CS2 in solvent C6H6 as mentioned in Fini's paper.

[Effects of Chinese herbal medicine Jiangzhi Granule on expressions of liver X receptor α and sterol regulatory element-binding protein-1c in a rat model of non-alcoholic fatty liver disease].

OBJECTIVE: To study the effects of Jiangzhi Granule (JZG), a compound traditional Chinese herbal medicine, in regulating liver X receptor α (LXRα) and sterol regulatory element-binding protein-1c (SREBP-1c) expressions in a rat model of non-alcoholic fatty liver disease (NAFLD). METHODS: Forty specific pathogen-free Wistar male rats were randomly divided into normal group, untreated group, pioglitazone (PIO) group and JZG group. All rats were fed with high-fat diet (88% normal chow plus 10% lard plus 2% cholesterol) for 4 weeks except for the normal group. After the NAFLD model was established, PIO and JZG were fed to rats in the corresponding groups respectively for another 4 weeks. At the end of the 8th week, liver steatosis level was observed under a light microscope with hematoxylin and eosin (HE) staining; serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and triacylglycerol (TAG) and free fatty acid (FFA) contents in liver tissues were measured. LXRα and SREBP-1c expressions in liver tissues were determined by real-time polymerase chain reaction and Western blot methods. RESULTS: Compared with the normal group, there were physiological changes for hepatic steatosis in liver tissues in the untreated group as observed by HE staining. JZG improved serum ALT and AST levels which were significantly increased in the untreated group. Both JZG and PIO improved FFA and TAG levels in liver tissues which were significantly increased in the untreated group. mRNA and protein levels of LXRα and SREBP-1c in the untreated group were higher than those in the normal group, while the treatment of JZG and PIO lowered their expressions. CONCLUSION: JZG may regulate fatty acid metabolic disorder by decreasing the levels of LXRα and SREBP-1c.

[Study of Fermi resonance by means of solution concentration variation].

The values of Raman scattering coefficients of some molecules in which Fermi resonance occurs vary with solution concentration variation. We measured the Raman spectra of some solvents such as CCl4, CS2, C6H6, etc by changing the concentration of the solutions ranging from 10% to 100% in volume. As a result, the authors obtained the general law of Fermi resonance. We found some weak Fermi resonance phenomena as well that the two bands of Raman spectrum shift asymmetrically and that the fundamental of overtone is tuned by Fermi resonance and moves towards the same direction with the overtone simultaneously, which is same as the results Bier K. D. obtained by means of high-pressure technique. By means of this method, the authors demonstrated the conclusion that only the fundamental in combinations which has the same symmetry as the fundamental involved in Fermi resonance directly can its intensity variation influence the Fermi resonance. In this article, the authors present a new method to study Fermi resonance. This method is valuable in the identification and the assignment of spectral lines of solutions, the determination of molecular configuration of enzyme, the discrimination of isomer, as well as the influences on the molecular structures and properties caused by hydrogen bond.

Dangfei liganning capsules attenuate the susceptibility of rat nonalcoholic fatty liver to carbon tetrachloride toxicity.

OBJECTIVE: To test whether nonalcoholic hepatic steatosis sensitizes carbon tetrachloride (CCl4)-induced liver injury, and to assess the therapeutic effect of Chinese medicine extracts of Dangfei Liganning capsules and their potential underlying mechanisms. METHODS: Male Wistar rats were fed a high-fat diet to induce nonalcoholic fatty liver disease (NAFLD) or a normal diet (N). Eight weeks later, a nonlethal dose of CCl4 was applied intraperitoneally. From the start, HF-CCl4 rats were administered daily Dangyao extracts (D), Dangfei Liganning capsules (DF), or Diammonium Glycyrrhizinate (G) intragastrically. Rats were sacrificed 48 h after CCl4 administration. In addition to serum biochemistry, liver histopathology was observed using hematoxylin-eosin (HE) and oil red O staining, and hepatic levels of triglyceride (TG), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), caspase-3 activation and cytochrome P450 (CYP2E1) expression were assessed. RESULTS: There was almost no response to the nonlethal dose of CCl4 in the N control group. However, the HF group demonstrated massive steatosis, and elevated levels of serum ALT and AST, liver MDA, CYP2E1, and caspase-3 activation, whereas the levels of GSH and SOD were significantly decreased. All indexes assessed were dramatically worse in the HF-CCl4 group compared to the HF group, in addition to the more severe steatosis, hepatocyte ballooning, and inflammatory infiltration apparent in the centrilobular area. The medicines we tested affected the pathological changes in HF-CCl4 rats to differing degrees: DF and G led to improvements in all of the above examined indexes, including an obvious improvement in histopathology, and DF improved serum ALT and MDA levels more markedly than G, whereas D extracts produced only mild liver injury attenuation. CONCLUSION: Liver with NAFLD is more sensitive to hepatotoxicity; furthermore, the disrupted balance of oxidative stress and anti-oxidant defense contributes to the underlying mechanisms. Dangfei Liganning capsules potentially decrease this toxic susceptibility and alleviate liver injury in non-alcoholic fatty liver.

[Immunophenotypic comparison of adipose-derived mesenchymal stem cells from the greater omentums and subcutaneous adipose tissues of rats].

OBJECTIVE: To compare the adipose-derived mesenchymal stem cells (ADMSCs) isolated from the greater omentums and subcutaneous adipose tissues of rats for their characteristics in cell morphology, growth kinetics and immunophenotypes. METHODS: ADMSCs were isolated from the greater omentums and inguinal fat pads of 6 SD rats and cultured in vitro. The morphologies of the ADMSCs were observed using phase-contrast microscopy, and their growth curves were generated and the doubling times determined. The phenotypic marker profiles including CD11b, CD29, CD45, CD49d, CD90 and CD106 of the ADMSCs in the fourth passage were determined using flow cytometry. RESULTS: The ADMSCs harvested from the greater omentums and inguinal fat pads showed almost identical morphologies. The growth curves and the mean doubling time of the ADMSCs from the two different sources showed no obvious difference. With similar positivity rates for CD11b, CD29, CD106 and CD90, the two ADMSCs exhibited different expression rates of CD45 and CD49d. CONCLUSIONS: The immunophenotypic characteristics of the ADMSCs from the greater omentums and subcutaneous adipose tissues are not totally identical.

Roux-en-Y gastric bypass promotes expression of PDX-1 and regeneration of beta-cells in Goto-Kakizaki rats.

AIM: To study the effects of Roux-en-Y gastric bypass (RYGB) on the expression of pancreatic duodenal homeobox-1 (PDX-1) and pancreatic beta-cell regeneration/neogenesis, and their possible mechanisms in diabetics. METHODS: Three groups of randomly selected non-obese diabetic Goto-Kakizaki (GK) rats were subjected to RYGB, sham-RYGB and sham-operation (sham-op) surgery, respectively. The rats were euthanized at post-operative 1, 2, 4 and 12 wk. Their pancreases were resected and analyzed using reverse transcription polymerase chain reaction to detect the mRNA of PDX-1. Anti-PDX-1 immunohistochemical (IHC) staining and Western blotting were used to detect the protein of PDX-1. Double IHC staining of anti-Brdu and -insulin was performed to detect regenerated beta-cells. The index of double Brdu and insulin positive cells was calculated. RESULTS: In comparison with sham-RYGB and sham-op groups, a significant increase in the expressions of PDX-1 mRNA in RYGB group was observed at all experimental time points (1 wk: 0.378 +/- 0.013 vs 0.120 +/- 0.010, 0.100 +/- 0.010, F = 727.717, P < 0.001; 2 wk: 0.318 +/- 0.013 vs 0.110 +/- 0.010, 0.143 +/- 0.015, F = 301.509, P < 0.001; 4 wk: 0.172 +/- 0.011 vs 0.107 +/- 0.012, 0.090 +/- 0.010, F = 64.297, P < 0.001; 12 wk: 0.140 +/- 0.007 vs 0.120 +/- 0.010, 0.097 +/- 0.015, F = 16.392, P < 0.001); PDX-1 protein in RYGB group was also increased significantly (1 wk: 0.61 +/- 0.01 vs 0.21 +/- 0.01, 0.15 +/- 0.01, F = 3031.127, P < 0.001; 2 wk: 0.55 +/- 0.00 vs 0.15 +/- 0.01, 0.17 +/- 0.01, F = 3426.455, P < 0.001; 4 wk: 0.39 +/- 0.01 vs 0.18 +/- 0.01, 0.22 +/- 0.01, F = 882.909, P < 0.001; 12 wk: 0.41 +/- 0.01 vs 0.20 +/- 0.01, 0.18 +/- 0.01, F = 515.833, P < 0.001). PDX-1 mRNA and PDX-1 protein production showed no statistical significance between the two sham groups. Many PDX-1 positive cells could be found in the pancreatic islets of the rats in RYGB group at all time points. In addition, the percentage of Brdu-insulin double staining positive cells was higher in RYGB group than in the other two groups (1 wk: 0.22 +/- 0.13 vs 0.03 +/- 0.06, 0.03 +/- 0.06, P < 0.05; 2 wk: 0.28 +/- 0.08 vs 0.00 +/- 0.00, 0.03 +/- 0.06, P < 0.05; 4 wk: 0.24 +/- 0.11 vs 0.07 +/- 0.06, 0.00 +/- 0.00, P < 0.001; 12 wk: 0.20 +/- 0.07 vs 0.03 +/- 0.06, 0.00 +/- 0.00, P < 0.05). CONCLUSION: RYGB can increase the expression of pancreatic PDX-1 and induce the regeneration of beta-cells in GK rats. The associated regeneration of islet cells may be a possible mechanism that how RYGB could improve type 2 diabetes mellitus.

[Effect of the change in fundamental Raman scattering coefficient with the concentration on Fermi resonance in binary solution].

The Raman scattering coefficients of the fundamental v1 (992 cm(-1)) of C6 H6 and the fundamental v1 (656 cm(-1) ) of CS2 changed dramatically with relative concentration of the binary solution of CS2 and C6 H6. The Raman spectra of the binary solution with different relative concentrations were measured. The results show that both the v1 fundamentals intensities changed dramatically with the relative concentration of the solution and the fundamental v1 of C6 H6 has little effect on the Fermi resonance v1 +v6-v8. On the contrary, the change in the v1 fundamental intensity of the CS2 changed which has more effect not only on the Fermi resonance v1 - 2v2 but also on the v2 fundamental. In this report, the experimental results were analyzed based on the J. F. Bertran theory and group theory.