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1.
J Affect Disord ; 261: 164-171, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31630038

RESUMO

BACKGROUND: To study the association of n-3 polyunsaturated fatty acid (n-3 PUFA) intake from diet with depressive symptoms in midlife women. METHODS: Data for this cross-sectional study were retrieved from baseline assessment of the Study of Women's Health Across the Nation (SWAN). Logistic regression and restricted cubic spline models were performed to examine the association n-3 PUFA intake with depressive symptoms. RESULTS: A total of 3054 women aged 42-52 years were included in the present study. In overall midlife women, n-3 PUFA intake was not significantly associated with depressive symptoms (CES-D score ≥16) after adjustment for potential confounders. In early perimenopausal women, n-3 PUFA intake was inversely associated with depressive symptoms after adjustment for potential confounders. The fully adjusted OR with 95% CI of depressive symptoms were 0.062 (0.009-0.457) in the highest quartile (n-3 PUFAs intake was categorized by quartiles) compared with the lowest quartile for n-3 PUFA intake. Restricted cubic spline analyses showed that n-3 PUFA intake were dose-response inversely associated with depressive symptoms in early perimenopausal women. However, in premenopausal women, no significant association between depressive symptoms and n-3 PUFA intake was observed. LIMITATIONS: This was a cross-sectional study, limiting causal inferences. CONCLUSION: Dietary n-3 PUFA may be inversely associated with depressive symptoms in early perimenopausal women, but not in premenopausal women.

2.
J Affect Disord ; 260: 194-199, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499375

RESUMO

BACKGROUND: To study the association of trans fatty acid intake from diet with depressive symptoms in midlife women. METHODS: Data for this cross-sectional study were retrieved from baseline assessment of the Study of Women's Health Across the Nation (SWAN). Linear regression, logistic regression and restricted cubic spline models were performed to examine the association trans fatty acid intake with depressive symptoms. RESULTS: A total of 3095 women aged 42-52 years were included in the present study. Trans fatty acid intake was positively associated with CES-D (Center for Epidemiological Studies-Depression) scores in unadjusted, age-, race/ethnicity-, total family income- and education-adjusted and fully adjusted linear regression model. The fully adjusted regression coefficient with 95% confidence intervals (CIs) of trans fatty acid intake were 0.146 (0.047-0.246) for CES-D score. Trans fatty acid intake was positively associated with depressive symptoms (CES-D score ≥16) in each logistic regression model. The fully adjusted odds ratios (ORs) with 95% CI of depressive symptoms were 1.410 (1.019-1.951) in quartile 4 compared with quartile 1 for trans fatty acid intake. Sensitivity analyses showed that the association between trans fatty acid and depressive symptoms were not affected by use of antidepressant. Stratified analysis showed that, in fully adjusted model, the trans fatty acid intake was not significantly associated with depressive symptoms in early perimenopausal women. LIMITATIONS: This was a cross-sectional study, limiting causal inferences. CONCLUSION: Trans fatty acid may be positively associated with depressive symptoms in premenopausal women, but not in early perimenopausal women.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31446160

RESUMO

Neuroinflammation and metabolic deficits contribute to the etiology of human affective disorders, such as anxiety and depression. The zebrafish (Danio rerio) has recently emerged as a powerful new model organism in CNS disease modeling. Here, we exposed zebrafish to 2% glucose and 10% cholesterol for 19 days to experimentally induce type 2 diabetes (DM) and to assess stress responses, microglia, inflammation and apoptosis. We analyzed zebrafish anxiety-like behavior in the novel tank and light-dark box (Days 15-16) tests, as well as examined their biochemical and genomic biomarkers (Day 19). Confirming DM-like state in zebrafish, we found higher whole-body glucose, triglyceride, total cholesterol, low-density lipoprotein levels and glucagon mRNA expression, and lower high-density lipoprotein levels. DM zebrafish also showed anxiety-like behavior, elevated whole-body cortisol and cytokines IFN-γ and IL-4, as well as higher brain mRNA expression of the glucocorticoid receptor, CD11b (a microglial biomarker), pro-inflammatory cytokines IL-6 and TNF-α (but not IL-1ß or anti-inflammatory cytokines IL-4 and IL-10), GFAP (an astrocytal biomarker), neurotrophin BDNF, its receptors p75 and TrkB, as well as apoptotic Bax and Caspase-3 (but not BCl-2) genes. Collectively, this supports the overlapping nature of DM-related affective pathogenesis and emphasizes the role of peripheral and central inflammation and apoptosis in DM-related affective and neuroendocrine deficits in zebrafish.

4.
J Pharm Biomed Anal ; 177: 112809, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31541942

RESUMO

A simple and specific, rapid resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for determination of chlorogenic acid in human plasma using neochlorogenic acid as the internal standard. Plasma samples were precipitated with methanol and separated on a Zorbax C18 column (50 × 2.1 mm, i.d. 1.8 µm) at a flow rate of 0.4 mL/min using a gradient mobile phase of methanol-water containing 0.1% formic acid (v/v). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring in negative ESI mode. The method was fully validated over the concentration range of 10-2000 ng/mL. The indicators of inter- and intra-day precision (RSD%) were all within 10.7%, and the accuracy (RE%) was ranged from -3.0% to 10.6%. Moreover, we evaluated this bioanalytical method by re-analysis of incurred samples as an additional measure of assay reproducibility. This method was successfully applied to pharmacokinetic study of CGA in Chinese subjects with advanced solid tumor after intramuscular injection administration of Chlorogenic acid for injection (CAFI).

5.
Biomed Pharmacother ; 121: 109425, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726370

RESUMO

Gastric carcinoma (GC) is still one of the most common digestive system neoplasms and the primary reason for malignant cancer-associated death. Long non-coding RNAs (lncRNAs) have been reported to play critical roles in GC progression. In this study, we demonstrated that lncRNA testis development-related gene 1 (TDRG1) is markedly upregulated in clinical GC tissues and GC cells. High level of lncRNA TDRG1 correlates with the metastasis and prognosis of patients with GC. Overexpression of lncRNA TDRG1 promotes GC growth and metastatic-related traits in vitro and in vivo, and silencing TDRG1 causes opposite results. We future find that TDRG1 is inversely associated with miR-873-5p and positively modulates the expression of hepatoma-derived growth factor (HDGF), a functional target gene of miR-873-5p. Finally, lncRNA TDRG1 regulates the progression of GC through regulating miR-873-5p/HDGF pathway. Taken together, our data uncover the crucial function of TDRG1-miR-873-5p-HDGF axis in human gastric cancer.

6.
Biomed Pharmacother ; 121: 109574, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31766097

RESUMO

This study aimed to investigate the levels of growth differentiation factor 15 (GDF15), a stress-induced factor, and sex hormones in male patients with HBV-related hepatocellular carcinoma (HCC) and the association between the two. In this study, we recruited 298 male participants including 83 healthy individuals as controls, 67 patients with chronic hepatitis B (CHB), 56 patients with HBV-related liver cirrhosis (HBV-related LC), and 92 patients with HBV-related HCC. Serum levels of GDF15, total testosterone (TT), estradiol (E2), free testosterone (FT) and other biochemical variables were measured. Serum GDF15 levels were significantly increased and serum FT and free testosterone/estradiol ratio (FT/E2 ratio) were significantly decreased in HCC compared with healthy controls and CHB patients, though there was no significant difference between HCC and LC patients. Furthermore, the Barcelona Clinic Liver Cancer stage C (BCLC-C) and BCLC-B patients had higher GDF15 levels than those in the controls and BCLC-A patients (all P<0.05). In addition, levels of FT were significantly reduced in BCLC-B and BCLC-C patients compared to controls (all P<0.05). The FT/E2 ratio was significantly decreased in all HCC staging patients compared with controls (all P<0.05). Correlation analyses showed that GDF15 levels were inversely correlated with TT levels (r =-0.326, P = 0.002), FT levels (r =-0.344, P<0.001) and E2 (r =-0.206, P<0.05). Together, these results suggest that upregulation of GDF15, downregulation of FT and FT/E2 ratio may be involved in the outcome of HBV infection and the severity of HCC. And high levels of serum GDF15 were negatively associated with sex hormones in male patients with HBV-related HCC, suggesting an important role of GDF15 in the presence of low and imbalanced sex hormones levels. Thus, regulation of GDF15 levels by rebalancing sex hormones has the potential to guide strategies for new cancer therapeutics.

7.
J Antibiot (Tokyo) ; 73(1): 35-39, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31434994

RESUMO

A Gram-staining positive and nonmotile strain designated SYSUP0005T was isolated from tubers of Gastrodia elata Blume. The 16S rRNA gene sequence result showed that strain SYSUP0005T shared highest sequence similarity with the type strain of Amycolatopsis cappadoca (95.7%), Amycolatopsis taiwanensis (95.4%), Amycolatopsis pigmentata (95.4%), Amycolatopsis ruanii (95.1%), and Amycolatopsis helveola (94.8%). Growth occurs at 14-37 °C (optimum temperature, 28 °C), at pH 6-9 (optimum, pH 8) and in the presence of up to 6% (w/v) NaCl. Strain SYSUP0005T had meso-diaminopimelic acid in its peptidoglycan. The whole cell sugars were galactose, ribose, and xylose. The predominant menaquinone was MK-9(H4) and minor menaquinones were MK-9(H2) and MK-9(H8). The polar lipids were diphosphatidylglycerol (DPG); phosphatidylmonomethylethanolamine (PME), phosphatidylethanolamine (PE), phosphatidylinositol (PI), unidentified glycolipid (GL), and unidentified phospholipid (PL). The genomic DNA G + C content was 69.6 mol%. The major fatty acids were iso-C16:0, anteiso-C17:0, C16:0, iso-C14:0, C17:1 ω6c, C17:0, and Summed Feature 3 (C16:1 ω7c/C16:1 ω6c). On the basis of the phenotypic, phylogenetic, chemotaxonomic characters, and genomic comparison, SYSUP0005T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis alkalitolerans sp. nov. is proposed. The type strain is SYSUP0005T (=KCTC 49024T = CGMCC4.7463T).

8.
J Hypertens ; 38(1): 82-94, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31356401

RESUMO

BACKGROUND: Endothelial progenitor cells (EPCs) play a crucial role in the endothelial repair after arterial injury. Shear stress has a beneficial effect on modulating EPC functions. The molecular mechanism underlying the influence of EPCs on the endothelial integrity and shear stress effects on EPC regulation remained unclear. Herein, we investigated the influence of ß2 adrenergic receptor (ß2AR)-dependent signaling on in-vitro shear stress-mediated function and in-vivo reendothelialization capacity of human EPCs. METHOD: The human EPCs from healthy population were exposed to in-vitro 5, 10, and 20 dyn/cm shear stress for 15 h, and 10 dyn/cm for 5, 10, and 15 h, respectively. The in-vitro proliferation was assessed by CCK8 and BrDU tests. The migration and adhesion were evaluated by Transwell system and human umbilical vein endothelial cells (HUVECs) incorporation assays. Meanwhile, the angiogenic cytokine stromal derived factor-1 (SDF-1) and vascular endothelial growth factor (VEGF) concentration of supernatant were tested by ELISA. Phosphorylated ß2AR, Akt, and eNOS were detected by western blot. In an in-vivo study, mice carotid injury models were produced through denuding the endothelium with a curved flexible wire, and thereafter CM-Dil-labeled EPCs were injected intravenously. After 3 days, cells recruited to the injury sites were detected by fluorescent microscopy, and the in-vivo reendothelialization capacity was assessed by Evans blue dye. RESULTS: Shear stress improved in-vitro functions and in-vivo reendothelialization capacity of human EPCs. In parallel, shear stress up-regulated the phosphorylation of ß2AR, Akt, and eNOS, and promoted vascular endothelial growth factor (VEGF) secretion of human EPCs. With ICI118,551 (a ß2AR inhibitor) treatment, shear stress-induced Akt and eNOS phosphorylation as well as VEGF secretion were suppressed. After ß2AR/PI3K/Akt/eNOS pathway of EPCs was blocked, the effects of shear stress on in-vitro functions and in-vivo reendothelialization capacity of EPCs were inhibited. CONCLUSION: The present study provided the novel data that shear stress-induced ß2AR/Akt/eNOS pathway enhanced reendothelialization capacity of EPCs. Shear stress-induced ß2AR-dependent pathway may be a novel and important therapeutic target for endothelial repair.

9.
J Environ Manage ; 253: 109732, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31698331

RESUMO

Numerous studies have shown that a wide range of pharmaceuticals are present in the environment and many of their adverse biological effects on the aquatic ecosystem and human health are unknown. Due to the high population density and large number of pharmaceuticals produced and consumed in China, a systematic approach is needed to identify pharmaceuticals that require greater attention. The present study provides a ranking of pharmaceuticals in China in terms of their occurrence (O), persistence, bioaccumulation, and toxicity (PBT) based on the predicted environmental concentration (PEC). The total and partial ranking method implemented in the decision analysis by ranking techniques (DART) tool was used, which is an easy-to-use tool for the analysis of datasets. Using the DART approach, 10 pharmaceuticals were selected as priority compounds. These pharmaceuticals included antibiotics, anti-inflammatory and antilipidemic. In order to identify the characteristics of the priority pharmaceuticals, ecotoxicological endpoints were considered. The results of this study and the priority list facilitate the selection of candidate pollutants in future monitoring studies.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental , Humanos , Medição de Risco
10.
Biochim Biophys Acta Mol Basis Dis ; 1866(1): 165578, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672550

RESUMO

Atherosclerosis is an inflammatory disease of the arterial wall, which involves endothelial cells and immune cells. Endothelial dysfunction has been considered an important step in the initiation of the disease. TIPE1 is a newly identified protein of the TIPE family, and plays a vital role in inflammation and tumorigenesis. However, its role in atherogenesis remains unclear. In this study, we demonstrated that TIPE1 promoted atherogenesis by inducing endothelial dysfunction. When human umbilical vein endothelial cells (HUVECs) were exposed to oxidative stress, the level of TIPE1 was significantly up-regulated, and the ROS generation markedly increased in TIPE1 over-expressing HUVECs. As a result, the growth of HUVECs was inhibited, and the apoptosis was enhanced. However, the cell contact ability between HUVECs and THP-1 cells were augmented due to the up-regulation of adhesion molecules such as E-selectin and ICAM-1 induced by TIPE1 overexpression. Importantly, ApoE-/- mice injected with TIPE1 recombinant lentivirus developed significantly severe atherosclerosis accompanied by hyperglycemia, hypercholesterolemia and increased white blood count. These findings indicated that excessive ROS induced by the overexpression of TIPE1 in endothelial cells accelerated the process of atherogenesis.

11.
Cancer Lett ; 468: 27-40, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604115

RESUMO

Patients with recurrent nasopharyngeal carcinoma (NPC) have more co-existing distant metastasis than those of no-recurrence and are more likely to suffer distant metastasis after re-irradiation than patients with newly diagnosed NPC. However, the relationship between radioresistance and distant metastasis and the mechanisms involved in radioresistance-associated metastasis are still unclear. In this study, we proved that C-C motif chemokine ligand 2 (CCL2) expression was significantly elevated in HONE1-IR cells and recurrent NPC tumour. Inhibition of CCL2 enhanced sensitivity to radiotherapy in NPC cells. Moreover, autocrine CCL2 promoted NPC cell adaptive radioresistance, metastasis and epithelial-mesenchymal transition. Additionally, p53 activated CCL2 transcription. High CCL2 expression was highly associated with poorer locoregional recurrence free survival, progression free survival and overall survival in patients with newly diagnosed NPC. Notably, high CCL2 expression was an independent prognostic factor for distant metastasis free survival in recurrent NPC patients. Our results provide insights into the autocrine signalling mechanisms of CCL2 and suggest that inhibition of autocrine CCL2 may be a candidate treatment strategy for management of radioresistant NPC.

12.
Biosens Bioelectron ; 147: 111752, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630033

RESUMO

The sensitive and efficient strategy remains a central challenge for early diagnosis of pathogenic bacteria. Herein, an ultrasensitive electrochemical biosensor was proposed based on the multiple amplification strategy via the 3D DNA walker, rolling circle amplification (RCA) and hybridization chain reaction (HCR) for the accurate detection of Escherichiacoli O157:H7 (E. coli O157:H7). Firstly, the target sequence extracted from E. coli O157:H7 was transformed and amplified by the DNA walker firstly. Subsequently, a large number of transformed nucleic acid sequences were amplified by the RCA reaction. And then, the progress of HCR was triggered by every fragment in RCA products to form a long double-stranded DNA sequence to immobilize electrochemical indicators, generating a significantly enhanced electrochemical signal. As expected, a high sensitivity with a detection limit of 7 CFU/mL was achieved based on the proposed multiple amplification strategy, which is superior to most current methods for E. coli O157: H7 assay. The multiple amplification strategy could be readily expanded for the detection of various pathogenic bacteria, providing a new approach for early diagnosis of pathogenic microorganisms or other diseases.

14.
Chemosphere ; 240: 124866, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31546191

RESUMO

Three series of co-graft cationic starch (St)-based flocculants with distinct structural characteristics, namely, charge density (CD), graft-chain length (L), and graft-chain distribution (N), were successfully synthesized through graft copolymerization of [(2-methacryloyloxyethyl) trimethyl ammonium chloride] and acrylamide. These St-based flocculants with different molecular structures were used to flocculate various kaolin suspensions with different initial turbidities and a sodium humate (NaHA) aqueous solution. The experimental results indicated that CD contributed to flocculation evidently, whereas average L and its N were insignificant in experimentally measured ranges. On the basis of phenomenological theory, a second-order polynomial equation was used to further quantitatively analyze the effects of the three structural factors on the flocculation performance of these St-based flocculants, which were fully consistent with the experimental results. Besides, the optimal dose and its corresponding removal rate could be predicted exactly, and the flocculation mechanisms were discussed in detail according to the established models. With the combination of floc properties and zeta potentials, the flocculation mechanisms of these St-based flocculants for flocculation of kaolin suspensions and NaHA aqueous solution were mainly ascribed to charge patching and simple charge neutralization, respectively. These results improve the understanding of the structure-activity relationship of these graft St-based flocculants, which is of significant guidance for the utilization and design of novel flocculants.

15.
Talanta ; 207: 120313, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594600

RESUMO

Peptidomics research is of great significance for discovering potential biomarkers and monitoring human diseases. As a kind of common clinical biofluid, saliva known for its noninvasive collection and easy accessibility has been widely used in peptidomics research. In this article, we combined immobilized metal ions affinity chromotography (IMAC) with mesoporous material and proposed the copper ion doped magnetic mesoporous silica material (denoted as Fe3O4@mSiO2-Cu2+) which had a large surface area of 221 m2 g-1 and pore volume of 0.20 cm3 g-1. By immobilizing copper ions onto the mesopore walls, the standard peptide Angiotensin II could be identified in an extremely low concentration of 0.1 fmol µl-1 and in a mass ratio of 1:500 (Angiotensin II:BSA, m/m), which indicated significant sensitivity and a great size-exclusive ability. In addition, the introduction of polydopamine (PDA) made Fe3O4@mSiO2-Cu2+ more hydrophilic and biocompatible which could improve the profiling of endogenous peptides in bio-sample. Finally, 131 endogenous peptides were identified in human saliva after enrichment with Fe3O4@mSiO2-Cu2+. Therefore, Fe3O4@mSiO2-Cu2+ nanoparticles provided a promising candidate protocol for biomarker discovery.

16.
Carbohydr Polym ; 227: 115338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590863

RESUMO

New sources of AIE materials with good water solubility, biocompatibility, degradability, and mass production are urgently needed. Here, we found that chitosan, a very abundant polysaccharide in nature, has fluorescence emission in both solid and solution states with AIE effect, and explored its multifunctional applications. Chitosan can emit a variety of colors from blue to red at different excitation wavelengths with excellent multicolor imaging capabilities at the cellular level. Utilizing the cationic and antibacterial properties of chitosan, the quantification of bacteria can be achieved through the AIE effect. Concurrently, it can be used as fluorescent probes for multi-channel bacterial imaging via lighting-up bacteria. Furthermore, the chitosan solution exhibits a sensitive quenching response to Fe3+, which can be used as a biosensor for detecting the concentration of Fe3+. These interesting results indicate that chitosan will have broad application prospects as a new class of AIE material.

17.
Magn Reson Imaging ; 65: 129-135, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31644925

RESUMO

PURPOSE: To investigate the correlation between the FA parameters and Ki-67 labeling index, and their diagnostic performance in grading supratentorial non-enhancing gliomas and neuronal-glial tumors (GNGT). METHODS: This institutional review board-approved, Health Insurance Portability and Accountability (HIPAA) compliant retrospective study enrolled 35 patients, including 19 with low grade GNGT and 16 with high grade GNGT. The mean FA, maximal FA and mean maximal FA values derived from diffusion tensor imaging were measured. The correlation between the FA parameters and the Ki-67 labeling index was assessed by Spearman rank test. The receiver operating characteristic curve analysis and multivariate logistic regression analysis were performed to detect the optimal imaging parameters in grading GNGT. RESULTS: The three FA parameters of low grade GNGT were significantly lower than the high grade GNGT (p < 0.001). The mean FA, maximal FA and mean maximal FA had significant positive correlation with Ki-67 labeling index (p = 0.001, p < 0.001, p < 0.001 respectively). The maximal FA showed a higher sensitivity and specificity in grading of non-enhancing GNGT with specificity of 78.9%, sensitivity of 100.0%, respectively. CONCLUSIONS: The FA parameters correlated with Ki-67 labeling index, and were useful surrogates in preoperative grading supratentorial non-enhancing GNGT.

18.
Magn Reson Imaging ; 65: 55-61, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31655137

RESUMO

The habenulae consist of a pair of small nuclei which bridge the limbic forebrain and midbrain monoaminergic centers. They are implicated in major depressive disorders due to abnormal phasic response when provoked by a conditioned stimulus. The lateral habenula (Lhb) is believed to be involved in dopamine metabolism and is now a target for deep brain stimulation, a treatment which has shown promising anti-depression effects. We imaged the habenulae with susceptibility weighted imaging (SWI) and quantitative susceptibility mapping (QSM) in order to localize the lateral habenula. Fifty-six healthy controls were recruited for this study. For the quantitative assessment, we traced the structure to compute volume from magnitude images and mean susceptibility bilaterally for the habenula on QSM. Thresholding methods were used to delineate the Lhb habenula on QSM. SWI, true SWI (tSWI), and QSM data were subjectively reviewed for increased Lhb contrast. SWI, QSM, and tSWI showed bilateral signal changes in the posterior location of the habenulae relative to the anterior location, which may indicate increased putative iron content within the Lhb. This signal behavior was shown in 41/44 (93%) subjects. In summary, it is possible to localize the lateral component of the habenula using SWI and QSM at 3 T.

19.
J Phys Condens Matter ; 32(5): 055402, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600738

RESUMO

The coupling of lattice vibrations with macroscopic electric fields in ionic crystals is examined from first principles based on density functional theory and density functional perturbation theory. Our analyses show that the coupled optical phonon-photon modes are well represented by using the pure phonon modes evaluated at [Formula: see text] as a basis. In addition, we find that apparent 'discontinuities' and mode 'disappearances' in the phonon dispersion curves of ionic materials for [Formula: see text] in hexagonal and other anisotropic materials are caused by the directional dependence of the Born effective charge tensor which is responsible for this coupling. The full dispersion curves, including the phonon-photon transverse modes are shown to be continuous functions of wavevector. Our work in this report provides a promising tool for first principles evaluation of phonon polaritons that may be accessible to experiment. Explicit examples are explored for cubic and hexagonal BN; the calculated results are in good agreement with previous computational values and available experimental measurements.

20.
J Ethnopharmacol ; 246: 112221, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31494203

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Donkey (Equus asinus) milk has become a medical and nutrient product since ancient times. In addition, donkey milk was regarded as a medicinal food and substitute product for infant formula in some ancient western countries. Chinese ancient medical books documented the medicinal value of donkey milk, using donkey milk to treat diabetes, cough and jaundice. AIM OF THE STUDY: To investigate the donkey milk's components and anti-diabetic effect of donkey milk in vitro and in vivo and to study the molecular mechanism of donkey milk was an anti-diabetic medication. MATERIALS AND METHODS: In this study, the gastrointestinal digested donkey milk was simulated in vitro and its products of protein digestion were analyzed by SDS-PAGE. We then performed cell viability assay, insulin secretion assay, animal experiments and ELISA assays to study the anti-diabetic effect of donkey milk in vitro and in vivo. Donkey milk's anti-diabetic molecular mechanism and specific targets were detected by using quantitative real time PCR. RESULTS: Lysozyme (LZ) and α-lactalbumin (α-La) exhibited significantly lower digestibility and higher retention than the other components of donkey milk. In vitro, 500 µg/mL of donkey milk could improve damaged ß-cells viability significantly (P < 0.0001). In vivo, the blood glucose and HOMA-IR of diabetic rats treated with donkey milk were 14.23 ±â€¯5.18 mM and 74.94 ±â€¯23.62, respectively, whereas the diabetic group were 22.18 ±â€¯2.23 mM and 112.16 ±â€¯18.44, respectively (P < 0.01). The SOD value of donkey milk group was 265.87 ±â€¯21.29 U/L, while the SOD value of diabetic group was 193.20 ±â€¯52.07 U/L (P < 0.05). These results indicated that the blood glucose was reduced, the ability of the body to eliminate free radicals was enhanced, antioxidant levels in the body was increased, insulin resistance was improved in type 2 diabetic rats after donkey milk powder fed for 4 weeks. Furthermore, donkey milk could treat diabetes through down-regulating phosphoenolpyruvate carboxykinase 1 (Pck1) and glucose-6-phosphatase (G6PC). CONCLUSIONS: Donkey milk has played an important role in the treatment of type 2 diabetes, and contributed to the development of the donkey milk products.

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