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1.
Int J Biol Macromol ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31712153

RESUMO

Ganoderma lucidum polysaccharides (GLP), a kind of medicinal mushrooms, were widely used in southeastern countries with putative anti-diabetic effects. In order to unravel the underlying mechanism of its anti-diabetic effect, this study examines the effects of GLP on gut microbiota composition and functions in type 2 diabetes mellitus (T2DM) status. In this study, the effects of GLP on the gut microbiota and fecal metabolites in high-fat diet and streptozotocin-induced T2DM rats were examined by 16S rDNA sequencing and 1H NMR profiling. As a result, administration of GLP led to significant decreases in the levels of fasting blood glucose and insulin. Moreover, GLP treatment reduced the abundance of harmful bacteria, such as Aerococcus, Ruminococcus, Corynebactrium and Proteus, and increased the level of Blautia, Dehalobacterium, Parabacteroides and Bacteroides. The PICRUSt analysis indicated that GLP could restore the disturbed amino acids metabolism, carbohydrates metabolism, inflammatory substances metabolism and nucleic acid metabolism of gut bacterial community in T2DM rats and most metabolic changes observed by metabolomics analysis were consistent with these consequences. Taken collectively, GLP can restore the disordered gut microbiota of T2DM rats to a normal level and modify metabolites of the host to realize its antidiabetic effects.

2.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3435-3442, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621230

RESUMO

To examine the effects of soil structure improvement due to the amendment of biochar and polyacrylamide (PAM) on the chlorophyll fluorescence characteristics of rice leaves and the yield of rice, a pit cultivation experiment was carried out in a coastal reclamation region. Three levels of biochar (0%, 2% and 5% by the mass of 0-20 cm surface soil and noted as B1, B2 and B3, respectively) and PAM (0‰, 0.4‰ and 1‰ by the mass of 0-20 cm surface soil and noted as P1,P2 and P3, respectively) were applied to the adopted soil, respectively. The results of the three-year experiment showed that an appropriate application quantity of biochar and PAM could improve the fluorescence characteristics of rice leaves. However, high levels of biochar and PAM had no obvious or even a negative effect. Among all the treatments, the B2P2 treatment always had the highest the maximum photochemical efficiency (Fv/Fm), the actual photochemical efficiency of photosystem II (ΦPS2), the photochemical quenching coefficient (qP) and the non-photochemical quenching coefficient (NPQ) values during the whole growth period. The chlorophyll content (SPAD value) of rice leaves showed no significant difference among different biochar application levels. However, it showed significant differences among different PAM application levels, with the highest value under the soil amended with 0.4‰ PAM (the P2 treatment). The application of biochar and PAM had significant impacts on rice yield, with the highest yield, namely 7236 kg·hm-2, presenting under the B2P2 treatment, which was 28.5% higher than that of the control. The improved soil structure of the coastal saline soil due to the amendment of biochar and PAM affects rice yield mainly through its influences on the 1000-grain weight, the spike number per hole, the grain number per spike and the seed setting rate. It is concluded that improving soil structure by applying an appropriate quantity of biochar and PAM is conducive to increase the chlorophyll fluorescence characteristics and the yield of rice in the coastal reclamation region.


Assuntos
Oryza , Solo , Clorofila , Fluorescência , Folhas de Planta
3.
Phys Chem Chem Phys ; 21(37): 20822-20828, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31515548

RESUMO

Vibrational energy redistribution (VER) of energetic materials plays an important role in transferring the injected energy to the hot spots, but it is extremely challenging to understand the mechanism of VER from experimental or theoretical studies. Here, we combined nonequilibrium molecular dynamics with density functional theory to study the processes of VER for solid nitromethane after the selective excitation of the C-H stretching vibration. The VER processes are traced by monitoring the normal-mode kinetic energies of both excited and unexcited vibrations. To explore the underlying VER mechanism, we also analyzed the spectral energy density for the normal mode, obtained from the squared modulus of the short-time Fourier transition of their normal mode momentum. The results showed that the simulated VER progress was reproduced well compared with the previous 3D IR-Raman experiments of liquid nitromethane. Interestingly, the symmetric dependence of the coupling mechanism between the normal modes has been found.

4.
Molecules ; 23(8)2018 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-30060618

RESUMO

Obesity and nonalcoholic fatty liver disease (NAFLD) are highly prevalent and cause numerous metabolic diseases. However, drugs for the prevention and treatment of obesity and NAFLD remain unavailable. In this study, we investigated the effects of mogrosides (luo han guo, LH) in Siraitia grosvenorii saponins on high-fat-diet-induced obesity and NAFLD in mice. We found that compared with the negative control, LH reduced body and liver weight. LH also decreased fat accumulation and increased AMP-activated protein kinase (AMPK) phosphorylation (pAMPK) levels in mouse livers. We also found that high-purity mogroside V upregulated pAMPK expression in HepG2 cells. In addition, high-purity mogroside V inhibited reactive oxygen species production and upregulated sequestosome-1 (SQSTM1, p62) expression in THP-1 cells. These results suggest that LH may affect obesity and NAFLD by enhancing fat metabolism and antioxidative defenses. Mogroside V may be a main component of LH. However, the exact molecular mechanisms and active components responsible for the inhibitory effects of LH on obesity and NAFLD require further investigation.


Assuntos
Fármacos Antiobesidade/farmacologia , Anticolesterolemiantes/farmacologia , Momordica/química , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Triterpenos/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Anticolesterolemiantes/química , Anticolesterolemiantes/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Tamanho do Órgão/efeitos dos fármacos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Saponinas/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Proteína Sequestossoma-1/agonistas , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Células THP-1 , Triterpenos/química , Triterpenos/isolamento & purificação
5.
Sheng Wu Gong Cheng Xue Bao ; 33(5): 817-827, 2017 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-28876036

RESUMO

A rapid quantitative evaluation method for Siraitia grosvenorii cells was successfully developed based on plant cells' capacitance value detected by a viable cell mass monitor and the cryopreservation of S. grosvenorii suspension cells was optimized. The survival rate of S. grosvenorii cells was quantitatively measured by viable cell mass monitor and 2, 3, 5-triphenyltetrazolium chloride (TTC). An optimum cryoprotectant recipe is that the growth medium contained 10% sucrose and 10% DMSO. The experimental results also showed higher cell survival rates and cell viabilities were achieved when suspension cells were treated with pretreatment of 0.2 mol/L sucrose. With the increase of concentration of sucrose, however, the cell survival rate was decreased. And the cell survival rate represented a bell shape with the increase of pretreatment time. The highest cell survival rate and cell viability were obtained with the 9 h' s pretreatment. In addition, there was a good correlation between the cell survival rate measured by cell recovery test and that measured by viable cell mass monitor, while there were no significant differences in the cell morphology and the ability of mogrosides V production by S. grosvenorii cells cultured in suspension after cryopreservation. Therefore, the evaluation method developed based on the viable cell mass monitor has good feasibility and reliability.


Assuntos
Criopreservação , Cucurbitaceae/citologia , Células Vegetais/fisiologia , Sobrevivência Celular , Crioprotetores , Dimetil Sulfóxido , Reprodutibilidade dos Testes , Sacarose
6.
Opt Lett ; 42(19): 3793-3795, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28957129

RESUMO

An optical method based on the multiphonon-assisted anti-Stokes-to-Stokes fluorescence intensity ratio (ASFIR) has been developed for temperature sensing. The ASFIR of YAG:Ce is found to exhibit a near linear and monotonic temperature dependence. Based on these properties, a thermometry using the ASFIR technique has been demonstrated in the range extending from 300 to 800 K with a nearly constant sensitivity of 0.07% K-1 and a precision of ±2% at 800 K. Also, the conventional dual-Stokes emission bands intensity ratio of YAG:Ce is shown to depend non-monotonically on temperature; thus the suggested ASFIR technique offers an effective method for luminescence thermometry.

7.
J Sep Sci ; 40(21): 4264-4271, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28834206

RESUMO

A simple and sensitive gas chromatography with tandem mass spectrometry method was developed and validated for the simultaneous determination of borneol and muscone in rat plasma. The analytes and internal standard, naphthalene, were extracted using a convenient one-step liquid-liquid extraction method with ethyl acetate. The chromatographic separation was realized on a HP-5MS capillary column and detected in multiple reaction monitoring mode. Excellent linearity (R2  ≥ 0.996) was shown over 10.0-5000 ng/mL for borneol and 2.5-250 ng/mL for muscone. The lower limit of quantitation was 10 and 2.5 ng/mL for borneol and muscone, respectively. The intra- and interday precisions were less than 7.52%, and the accuracy values were between  -8.03 and 14.52%. The extraction recovery, matrix effect, and stability were sufficient to meet the Food and Drug Administration criteria. Meanwhile, the assay was successfully applied to the preclinical pharmacokinetic study of borneol and muscone following intravenous administration of Xingnaojing injection, a modern Chinese herbal medicine preparation.


Assuntos
/farmacocinética , Cicloparafinas/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Cromatografia Gasosa-Espectrometria de Massas , Administração Intravenosa , Animais , Ratos , Reprodutibilidade dos Testes
8.
J Phys Chem A ; 121(26): 4948-4952, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28610422

RESUMO

Selective excitation of C-H stretching vibrational modes, detection of intramolecular vibrational energy redistribution (IVR), and vibrational modes coupling in the electronic ground state of benzene are performed by using femtosecond time- and frequency-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy. Both of the parent modes in the Raman-active bands are coherently excited by an ultrafast stimulated Raman pump, giving initial excitations of 3056 cm-1 (A1g) and 3074 cm-1 (E2g) and subsequent IVR from the parent modes to daughter modes of 1181 and 992 cm-1, and the coherent vibrational coupling of the relevant modes is tracked. The directionality and selectivity of IVR and coherent coupling among all of the relevant vibrational modes are discussed in the view of molecular symmetry.

9.
J Phys Chem A ; 121(13): 2565-2571, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28319388

RESUMO

The femtosecond time-resolved multiplex coherent anti-Stokes Raman scattering (CARS) technique has been performed to investigate intramolecular vibrational redistribution (IVR) through vibrational couplings in 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) molecules. In the multiplex CARS experiment, the supercontinuum (SC) was used as broad-band Stokes light to coherently and collectively excite multiple vibrational modes, and quantum beats arising from vibrational couplings among these modes were observed. The IVR of RDX is visualized by a topological graph of these vibrational couplings, and with analysis of the topological graph, two vibrational modes, both of which are assigned to ring bending, are confirmed to have coupling interactions with most of the other vibrational modes and are considered to have a tendency of energy transfer with these vibrational modes. We suggest that the mode at 466 cm-1 is a portal of energy transfer from outside to inside of the RDX molecule and the mode at 672 cm-1 is an important transit point of energy transfer in the IVR.

10.
J Ethnopharmacol ; 202: 67-77, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28237302

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: YiQiFuMai Powder Injection (YQFM), a traditional Chinese medicine prescription re-developed based on Sheng-Mai-San, is a classical and traditional therapeutic for clinical heart failure (HF) and angina. However, its potential mechanism against HF remains unclear. AIM OF THE STUDY: The present study observes the therapeutic role of YQFM and mechanisms underlying its effects on coronary artery ligation (CAL)-induced myocardial remodeling (MR) and HF. METHODS: MR and HF were induced by permanent CAL for 2 weeks in ICR mice. Then mice were treated with YQFM (0.13g/kg, 0.26g/kg and 0.53g/kg) once a day until 2 weeks later. Cardiac structure and function were evaluated by echocardiography. Serum lactate dehydrogenase (LDH), creatine kinase (CK) and malondialdehyde (MDA) were measured by biochemical kits and cardiomyocyte morphology was assessed by hematoxylin-eosin (HE) staining. Myocardial hydroxyproline (HYP), serum amino-terminal pro-peptide of pro-collagen type III (PIIINP), and Masson's trichrome staining were employed to evaluate cardiac fibrosis. Circulating level of N-terminal pro-B-type natriuretic peptide (NT-proBNP) was tested by ELISA kit to predict prognosis of CAL-induced HF. Effects of YQFM on the mitogen-activated protein kinases (MAPKs) pathway after CAL operation was evaluated by Western blotting and immunohistochemistry assay. RESULTS: YQFM (0.53g/kg) improved the left ventricular (LV) function and structure impairment after 2 weeks in CAL mice. YQFM administration also decreased LDH and CK activities, circulating levels of MDA, PIIINP, NT-proBNP, and HYP contents. Moreover, YQFM ameliorated cardiac injury and fibrosis. Furthermore, YQFM (0.53g/kg) inhibited the myocardial phosphorylation of MAPKs in HF mice. CONCLUSION: Our findings suggest that YQFM attenuates CAL-induced HF via improving cardiac function, attenuating structure damage, oxidative stress, necrosis, collagen deposition, and fibrosis. In addition, YQFM ameliorates cardiac remodeling and HF, partially through inhibiting the MAPKs signaling pathways. These data provide insights and mechanisms into the widely application of YQFM in patients with HF, MI and other ischemic heart diseases.


Assuntos
Vasos Coronários/fisiopatologia , Medicamentos de Ervas Chinesas/farmacologia , Insuficiência Cardíaca/prevenção & controle , Insuficiência Cardíaca/fisiopatologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Animais , Creatina Quinase/metabolismo , Combinação de Medicamentos , Ecocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , L-Lactato Desidrogenase/metabolismo , Ligadura , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos ICR , Miocárdio/metabolismo , Pós
11.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1673-8, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26572018

RESUMO

This study focused on the nitrogen loss via runoff, change of nitrogen in different forms in surface water in paddy field, and grain yield, through further reduction of nitrogen fertilizer application rate under green manuring without basal dressing. Results showed that with 150 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil, no basal dressing could not only sharply reduce N concentration in surface water and decrease 17.2% of N loss, but also increase 2.8% of grain yield in comparison with basal dressing. It was a worthwhile farming method that inorganic nitrogen fertilizer was not used for basal dressing but for topdressing after return of green ma- nure to soil in Taihu Area. However, the grain yield would decrease if the rate of topdressing nitro- gen was excessively reduced or increased. After all, it was feasible to realize harmonization of grain yield and environmental benefits in Taihu Area, with 133 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil as well as no application of basal dressing, which could greatly reduce N fertilizer input and N loss as well as ensure rice yield.


Assuntos
Agricultura/métodos , Fertilizantes , Esterco , Nitrogênio/análise , Oryza , China , Solo/química , Água/química
12.
Rejuvenation Res ; 18(6): 517-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26058543

RESUMO

SMXZF, a combination of four active components including ginsenoside Rb1, ginsenoside Rg1, schizandrin, and DT-13 (6:9:5:4) that is derived from Sheng Mai San, has previously been shown to exhibit a neuroprotective effect against focal ischemia/reperfusion injury. Due to the key role of oxidative stress-induced neuronal apoptosis in the pathogenesis of stroke, we examined the effect of SMXZF in oxidative stress responses and related signaling pathways in differentiated pheochromocytoma (PC12) cells. Our results showed that incubation with 100 µM hydrogen peroxide (H2O2) for 12 hr could reduce cell viability and superoxide dismutase (SOD) activity with an increase of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA). In contrast, SMXZF alleviated oxidative stress by reducing the over-production of ROS and MDA in parallel to concentration dependently increasing SOD activity. In addition, SMXZF significantly attenuated H2O2-induced caspase-3 cleavage, Rho-associated coiled-coil-containing protein kinase-1 (ROCK1) activation, and myosin light-chain (MLC) phosphorylation. Inhibiting either caspase-3 or ROCK1 mimicked the effect. Consequently, our results suggest that SMXZF inhibits H2O2-induced neuronal apoptosis linked with the caspase-3/ROCK1/MLC pathway, which has also been confirmed to be a positive feedback loop in oxidative stress-injured PC12 cells. These findings support the pharmacological potential of SMXZF for neurodegenerative diseases and stroke.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Peróxido de Hidrogênio/farmacologia , Cadeias Leves de Miosina/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/química , Espaço Intracelular/metabolismo , Malondialdeído/metabolismo , Neurotoxinas/toxicidade , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Gene ; 555(2): 88-94, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25455099

RESUMO

Slc7a11 encoding solute carrier family 7 member 11 (amionic amino acid transporter light chain, xCT), has been identified to be a critical genetic regulator of pheomelanin synthesis in hair and melanocytes. To better understand the molecular characterization of Slc7a11 and the expression patterns in skin of white versus brown alpaca (lama paco), we cloned the full length coding sequence (CDS) of alpaca Slc7a11 gene and analyzed the expression patterns using Real Time PCR, Western blotting and immunohistochemistry. The full length CDS of 1512bp encodes a 503 amino acid polypeptide. Sequence analysis showed that alpaca xCT contains 12 transmembrane regions consistent with the highly conserved amino acid permease (AA_permease_2) domain similar to other vertebrates. Sequence alignment and phylogenetic analysis revealed that alpaca xCT had the highest identity and shared the same branch with Camelus ferus. Real Time PCR and Western blotting suggested that xCT was expressed at significantly high levels in brown alpaca skin, and transcripts and protein possessed the same expression pattern in white and brown alpaca skins. Additionally, immunohistochemical analysis further demonstrated that xCT staining was robustly increased in the matrix and root sheath of brown alpaca skin compared with that of white. These results suggest that Slc7a11 functions in alpaca coat color regulation and offer essential information for further exploration on the role of Slc7a11 in melanogenesis.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Camelídeos Americanos/genética , Cabelo , Pigmentação , Sequência de Aminoácidos , Sistema y+ de Transporte de Aminoácidos/genética , Animais , Sequência de Bases , Camelídeos Americanos/metabolismo , Clonagem Molecular , Perfilação da Expressão Gênica , Cabelo/metabolismo , Imuno-Histoquímica , Melaninas/metabolismo , Melanócitos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA/metabolismo , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Pele/metabolismo
14.
Molecules ; 19(8): 12676-89, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25140446

RESUMO

Mogroside IIE is a bitter triterpenoid saponin which is the main component of unripe Luo Han Guo fruit and a precursor of the commercially available sweetener mogroside V. In this study, we developed an enzymatic glycosyl transfer method, by which bitter mogroside IIE could be converted into a sweet triterpenoid saponin mixture. The reactant concentration, temperature, pH and buffer system were studied. New saponins with the α-glucose group were isolated from the resulting mixtures, and the structures of three components of the extract were determined. The structure-taste relationships of these derivatives were also studied together with those of the natural mogrosides. The number and stereoconfiguration of glucose groups present in the mogroside molecules were found to be the main factor to determine the sweet or bitter taste of a compound. The antioxidant and food safety properties were initially evaluated by their radical scavenging ability and via 7 day mice survival tests, respectively. The results showed that the sweet triterpenoid saponin mixture has the same favorable physiological and safety characteristics as the natural mogrosides.


Assuntos
Glicosídeos/química , Saponinas/química , Edulcorantes/química , Triterpenos/química , Animais , Antioxidantes/química , Frutas/química , Glicosídeos/síntese química , Análise de Perigos e Pontos Críticos de Controle , Camundongos , Oxirredução , Relação Estrutura-Atividade , Edulcorantes/administração & dosagem , Paladar , Triterpenos/síntese química
15.
Opt Express ; 22(3): 2414-22, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663532

RESUMO

Photodynamic therapy for deep-lying lesions needs an appropriate imaging modality, precise evaluation of tissue oxygen and an effective photosensitizer. Gadolinium based metalloporphyrins Gd(III)-HMME is proposed in this study as a potential multifunctional theranostic agent, as photosensitizer, ratiometric oxygen sensor and MRI contrast agent. The time resolved spectroscopy revealed the luminescence peak of Gd(III)-HMME at 710 and 779 nm with a lifetime of 64 µs in oxygen-free methanol to be phosphorescent. This phosphorescence is strongly dependent on dissolved oxygen concentration. Its intensity in oxygen saturated methanol solution is 21% of that in deoxygenated solution. The singlet oxygen quantum yields ΦΔ of HMME and Gd(III)-HMME in air saturated methanol solution were determined to be 0.79 and 0.40 respectively using comparative spectra method. These phenomena indicate that the oxygen sensibility and production of singlet oxygen of Gd(III)-HMME can fulfill the requirement of PDT treatment.


Assuntos
Gadolínio/química , Hematoporfirinas/química , Oxigênio/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Gadolínio/efeitos da radiação , Hematoporfirinas/efeitos da radiação , Luz , Medições Luminescentes , Teste de Materiais , Oxigênio/efeitos da radiação , Doses de Radiação , Coloração e Rotulagem
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2100-4, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24159855

RESUMO

Raman spectra of two typical carotenoids (beta-carotene and lutein) and some short (n = 2-5) polyenes were calculated using density functional theory. The wavenumber-linear scaling (WLS) and other frequency scaling methods were used to calibrate the calculated frequencies. It was found that the most commonly used uniform scaling (UFS) method can only calibrate several individual frequencies perfectly, and the systematic result of this method is not very good. The fitting parameters obtained by the WLS method are upsilon(obs)/upsilon(calc)) = 0.999 9-0.000 027 4upsilon(calc) and upsilon(obs)/upsilon(calc)= 0.993 8-0.000 024 8upsilon(calc) for short polyenes and carotenoids, respectively. The calibration results of the WLS method are much better than the UFS method. This result suggests that the WLS method can be used for the frequency scaling of the molecules as large as carotenoids. The similar fitting parameters for short polyenes and carotenoids indicate that the fitting parameters obtained by WLS for short polyenes can be used for calibrating the calculated vibrational frequencies of carotenoids. This presents a new frequency scaling method for vibrational spectroscopic analysis of carotenoids.


Assuntos
Carotenoides/análise , Polienos/análise , Análise Espectral Raman , Calibragem , Modelos Teóricos
17.
BMC Genomics ; 14: 389, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23758853

RESUMO

BACKGROUND: Previous molecular genetic studies of physiology and pigmentation of sheep skin have focused primarily on a limited number of genes and proteins. To identify additional genes that may play important roles in coat color regulation, Illumina sequencing technology was used to catalog global gene expression profiles in skin of sheep with white versus black coat color. RESULTS: There were 90,006 and 74,533 unigenes assembled from the reads obtained from white and black sheep skin, respectively. Genes encoding for the ribosomal proteins and keratin associated proteins were most highly expressed. A total of 2,235 known genes were differentially expressed in black versus white sheep skin, with 479 genes up-regulated and 1,756 genes down-regulated. A total of 845 novel genes were differentially expressed in black versus white sheep skin, consisting of 107 genes which were up-regulated (including 2 highly expressed genes exclusively expressed in black sheep skin) and 738 genes that were down-regulated. There was also a total of 49 known coat color genes expressed in sheep skin, from which 13 genes showed higher expression in black sheep skin. Many of these up-regulated genes, such as DCT, MATP, TYR and TYRP1, are members of the components of melanosomes and their precursor ontology category. CONCLUSION: The white and black sheep skin transcriptome profiles obtained provide a valuable resource for future research to understand the network of gene expression controlling skin physiology and melanogenesis in sheep.


Assuntos
Perfilação da Expressão Gênica , Cabelo/anatomia & histologia , Ovinos/anatomia & histologia , Ovinos/genética , Pigmentação da Pele/genética , Pele/metabolismo , Animais , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Melaninas/biossíntese , Análise de Sequência de RNA , Fatores de Transcrição/metabolismo
18.
BMC Genomics ; 13: 555, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23067000

RESUMO

UNLABELLED: AB BACKGROUND: MicroRNAs (miRNAs) are small, non-coding 21-25 nt RNA molecules that play an important role in regulating gene expression. Little is known about the expression profiles and functions of miRNAs in skin and their role in pigmentation. Alpacas have more than 22 natural coat colors, more than any other fiber producing species. To better understand the role of miRNAs in control of coat color we performed a comprehensive analysis of miRNA expression profiles in skin of white versus brown alpacas. RESULTS: Two small RNA libraries from white alpaca (WA) and brown alpaca (BA) skin were sequenced with the aid of Illumina sequencing technology. 272 and 267 conserved miRNAs were obtained from the WA and BA skin libraries, respectively. Of these conserved miRNAs, 35 and 13 were more abundant in WA and BA skin, respectively. The targets of these miRNAs were predicted and grouped based on Gene Ontology and KEGG pathway analysis. Many predicted target genes for these miRNAs are involved in the melanogenesis pathway controlling pigmentation. In addition to the conserved miRNAs, we also obtained 22 potentially novel miRNAs from the WA and BA skin libraries. CONCLUSION: This study represents the first comprehensive survey of miRNAs expressed in skin of animals of different coat colors by deep sequencing analysis. We discovered a collection of miRNAs that are differentially expressed in WA and BA skin. The results suggest important potential functions of miRNAs in coat color regulation.


Assuntos
Camelídeos Americanos/genética , MicroRNAs/metabolismo , Pele/metabolismo , Animais , Sequência de Bases , Biblioteca Gênica , MicroRNAs/genética , Análise de Sequência de RNA
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(5): 1348-51, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21800598

RESUMO

The absorption, fluorescence and time-resolved fluorescence spectra of Rhodamine 101 dye in both methanol and acidic methanol solutions were measured. The authors achieved the characteristic information of the absorption and fluorescence spectra, and obtained the S1 lifetimes. The authors assigned vibrational modes of the Rhodanmine 101 dye molecule through spontaneous Raman spectrum, infrared spectrum, and density function theory calculation. This work systemically characterizes the spectral, molecular structural, and vibrational information of Rhodamine 101 dye molecule, and provides necessary information for the application of Rhodamine 101 dye in dye sensitized solar cell and biological fluorescence marker.

20.
Opt Express ; 18(22): 22937-43, 2010 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-21164632

RESUMO

We have studied the ultrafast dynamics of coherent phonons in sapphire crystals irradiated with 60Co γ-rays for three different doses by femtosecond time-resolved coherent anti-Stokes Raman scattering (fs-CARS) technique at room temperature. The obtained fs-CARS signals exhibit well-defined quantum beats, which are ascribed to the interference of the 645 and 750 cm-1 phonon modes. The dephasing times of the two modes both decrease with increasing irradiation dose, which is due to the scattering of coherent phonons by the defects introduced by γ-ray irradiation.

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