31 research outputs found
Exceptional points in non-Hermitian Photonics: Applications and Recent Developments
Exceptional points are complex branching singularities of non-Hermitian bands
that have lately attracted considerable interest, particularly in non-Hermitian
photonics. In this article, we review some recent developments in non-Hermitian
photonic platforms such as waveguides, photonic crystals, Fabry-Perot
resonators and plasmonic systems, and suggest how optical non-linearities and
exceptional bound states can significantly impact the development of
non-Hermitian photonics in the near future
Effects of oligosaccharides from endophytic Fusarium oxysporum Dzf17 on activities of defense-related enzymes in Dioscorea zingiberensis suspension cell and seedling cultures
Background: Three oligosaccharides (EOS, WOS and SOS) were respectively
prepared from the corresponding polysaccharides, namely
exopolysaccharide (EPS), water-extracted mycelial polysaccharide (WPS)
and sodium hydroxide-extracted mycelial polysaccharides (SPS) from the
endophytic fungus Fusarium oxysporum Dzf17. In this study, the
effects of EOS,WOS and SOS on the activities of the defense-related
enzymes, namely phenylalanine ammonia lyase (PAL), polyphenoloxidase
(PPO) and peroxidase (POD) in its host plant Dioscorea zingiberensis
cultures were investigated. Results: For the suspension cell cultures
of D. zingiberensis, the highest PAL activity was induced by 0.5 mg/mL
of WOS at 48 h after treatment, which was 4.55-fold as that of control.
Both PPO and POD activities were increased to themaximumvalues by 0.25
mg/mL ofWOS at 48 h after treatment,whichwere respectively 3.74 and
3.45-fold as those of control. For the seedling cultures, the highest
PAL activity was elicited by 2.5 mg/mL of EOS at 48 h after treatment,
which was 3.62-fold as that of control. Both PPO and POD reached
theirmaximum values treatedwith 2.5 mg/mL ofWOS at 48 h after
treatment, whichwere 4.61 and 4.19-fold as those of control,
separately. Conclusions: Both EOS and WOS significantly increased the
activities of PAL, PPO and POD in the suspension cell and seedling
cultures of D. zingiberensis. The results suggested that the
oligosaccharides from the endophytic fungus F. oxysporum Dzf17 may be
related to the activation and enhancement of the defensivemechanisms of
D. zingiberensis suspension cell and seedling cultures
Investigation on the Potential Application of Na-Attapulgite as an Excipient in Domperidone Sustained-Release Tablets
In this study, Na-attapulgite was explored as an excipient to prepare domperidone sustained-release tablets and test them in accordance with United States Pharmacopoeia requirements. Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC) were employed to explore the compatibility between Na-attapulgite and domperidone. The XRD and DSC show no interaction between the drug and Na-attapulgite. The FTIR spectrum indicates a shift in the absorption of N-H in the drug molecule, which can be explained by the hydrogen bonding interaction between the N-H in the DOM molecule and the -OH on the surface of Na-ATP. The diameter, hardness, friability and drug content of the tablets were measured, and they all met the relevant requirements of the United States Pharmacopoeia. In addition, the tablets with Na-attapulgite as excipient exhibit a better release performance within the release time of 12 h. These results demonstrate that the domperidone sustained-release tablets have been successfully prepared by using Na-attapulgite as an excipient. The doping of Na-ATP in domperidone sustained-release tablets improves the cytocompatibility. Moreover, with the increase of Na-ATP content, cells proliferate remarkably and cell activity is significantly enhanced
The triglyceride glucose index was U-shape associated with all-cause mortality in population with cardiovascular diseases
Abstract Background The triglyceride and glucose (TyG) index has been considered a simple surrogate marker of insulin resistance, related to a high risk of mortality. However, few studies have investigated the specific relationship between the TyG index and all-cause mortality among population with cardiovascular diseases. Methods 2,072 participants with cardiovascular diseases were enrolled from the National Health and Nutrition Examination Survey (NHANES) 1999–2014. The TyG index was calculated as log [fasting triglycerides (mg/dL) x fasting glucose (mg/dL)/2]. Outcomes were all-cause mortality and cardiovascular mortality. The baseline levels of TyG associated with the risk of mortality were evaluated on a continuous scale (restricted cubic splines) and by a priori defined quantile categories with Cox regression models. Results After a follow-up of 16.8 years, 791 all-cause deaths and 184 cardiovascular deaths occurred. Restricted cubic splines showed that the association between levels of TyG index and the risk of all-cause mortality was non-linear (p < 0.001) and the TyG index associated with the lowest risk of all-cause mortality ranges 8.83 to 9.06 in individuals with cardiovascular diseases. Compared with the reference quartile of 8.84 ~ 9.29, the multivariate-adjusted hazards ratios and 95% confidence intervals were 1.40 (1.13–1.74; p = 0.002) in the lowest quartile and 1.08 (0.88, 1.32; p = 0.475) in the highest quartile for all-cause mortality. However, TyG was not associated with cardiovascular mortality. Conclusions TyG index was U-shape associated with the risk of all-cause mortality in participants with cardiovascular diseases and the level associated with the lowest risk ranged 8.83 to 9.06
Myricetin ameliorates atherosclerosis in the low-density-lipoprotein receptor knockout mice by suppression of cholesterol accumulation in macrophage foam cells
Abstract Background Myricetin, a major flavonoid found in several foods including berries, grapes and wine, exhibited strong antioxidant potency, yet the effect on atherosclerosis is not fully understood. In this study, we examined the effect of myricetin on lipid accumulation in macrophage and atherosclerosis in atherosclerosis-prone low density lipoprotein receptor-deficient (Ldlr −/− ) mice. Methods Ldlr −/− mice were fed an atherogenic diet supplemented with myricetin (0.15% in the diet, v/v) for 8 weeks. Body weight, adipose tissue weight, food intake, serum biochemical parameters were measured. Atherosclerosis lesions and macrophages accumulaton in lesions were analyzed and quantified. Macrophages were exposed to 20 μM of myricetin before incubated with oxidized low-density lipoprotein (ox-LDL) (25μg/mL) or Dil-ox-LDL for the indicated time. Lipid uptake and foam cell formation were evaluated by flow cytometry and microscopy. The intracellular lipids were extracted and measured. mRNA expression and protein of cholesterol metabolism related receptors were analyzed. Results Myricetin administration reduced the weight, plasma lipid levels but not food intake in Ldlr −/− mice when fed an atherogenic diet. Myceritin-treated Ldlr −/− mice displayed significantly less atherosclerotic areas and macrophages in the cross sections of the aortic root. There were also less lipophilic areas in En face Oil red O staining of aorta from myceritin-treated Ldlr −/− mice. Myceritin treatment also markedly ameliorated ox-LDL-induced cholesterol accumulation in macrophages. The expression of CD36 were decreased in myricetin treated macrophages with ox-LDL incubation, while scavenger receptors class A (SR-A) and scavenger receptors class B (SR-BI) expression was not altered, indicating that these effect of myricetin were dependent on CD36 pathway. Conclusions Our findings indicated that myricetin suppressed cholesterol accumulation in macrophage foam cells by inhibition of CD36-mediated ox-LDL uptake, and suggested myricetin may have an important therapeutic function for atherosclerosis
Role of Thylakoid Lipids in Protochlorophyllide Oxidoreductase Activation: Allosteric Mechanism Elucidated by a Computational Study
Light-dependent protochlorophyllide oxidoreductase (LPOR) is a chlorophyll synthetase that catalyzes the reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide) with indispensable roles in regulating photosynthesis processes. A recent study confirmed that thylakoid lipids (TL) were able to allosterically enhance modulator-induced LPOR activation. However, the allosteric modulation mechanism of LPOR by these compounds remains unclear. Herein, we integrated multiple computational approaches to explore the potential cavities in the Arabidopsis thaliana LPOR and an allosteric site around the helix-G region where high affinity for phosphatidyl glycerol (PG) was identified. Adopting accelerated molecular dynamics simulation for different LPOR states, we rigorously analyzed binary LPOR/PG and ternary LPOR/NADPH/PG complexes in terms of their dynamics, energetics, and attainable allosteric regulation. Our findings clarify the experimental observation of increased NADPH binding affinity for LPOR with PGs. Moreover, the simulations indicated that allosteric regulators targeting LPOR favor a mechanism involving lid opening upon binding to an allosteric hinge pocket mechanism. This understanding paves the way for designing novel LPOR activators and expanding the applications of LPOR
Effects of oligosaccharides from endophytic Fusarium oxysporum Dzf17 on activities of defense-related enzymes in Dioscorea zingiberensis suspension cell and seedling cultures
Background: Three oligosaccharides (EOS, WOS and SOS) were respectively prepared from the corresponding polysaccharides, namely exopolysaccharide (EPS), water-extracted mycelial polysaccharide (WPS) and sodium hydroxide-extracted mycelial polysaccharides (SPS) from the endophytic fungus Fusarium oxysporum Dzf17. In this study, the effects of EOS, WOS and SOS on the activities of the defense-related enzymes, namely phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD) in its host plant Dioscorea zingiberensis cultures were investigated.
Results: For the suspension cell cultures of D. zingiberensis, the highest PAL activity was induced by 0.5Â mg/mL of WOS at 48Â h after treatment, which was 4.55-fold as that of control. Both PPO and POD activities were increased to the maximum values by 0.25Â mg/mL of WOS at 48Â h after treatment, which were respectively 3.74 and 3.45-fold as those of control. For the seedling cultures, the highest PAL activity was elicited by 2.5Â mg/mL of EOS at 48Â h after treatment, which was 3.62-fold as that of control. Both PPO and POD reached their maximum values treated with 2.5Â mg/mL of WOS at 48Â h after treatment, which were 4.61 and 4.19-fold as those of control, separately.
Conclusions: Both EOS and WOS significantly increased the activities of PAL, PPO and POD in the suspension cell and seedling cultures of D. zingiberensis. The results suggested that the oligosaccharides from the endophytic fungus F. oxysporum Dzf17 may be related to the activation and enhancement of the defensive mechanisms of D. zingiberensis suspension cell and seedling cultures
Thermal Behavior and Char Structure Evolution of Bituminous Coal Blends with Edible Fungi Residue during Co-Pyrolysis
Co-pyrolysis of coal and lignocellulosic
biomass has the potential
to mitigate the emission of greenhouse gases from an energy supply.
Successful application of this technology requires proper investigation
on the influence of coal and lignocellulosic biomass mixing on thermal
behavior and product characteristics. Therefore, in this study, thermal
behavior of a kind of Chinese bituminous coal blended with edible
fungi residue (EFR) was evaluated through nonisothermal thermogravimertic
analysis. Raman spectroscopy and scanning electron microscopy with
energy dispersive spectroscopy techniques were applied to determine
the char structure evolution. The results revealed that the EFR promoted
thermal decomposition of the bituminous coal and synergy effect on
char yield was observed. The activation energy distribution calculated
via an isoconversional method showed nonadditivity performance, which
may be caused by the catalytic effects of alkali and alkaline earth
metals and the char structure evolution. The Raman spectrum results
indicated that the Raman intensity of the co-pyrolysis char increased
with the EFR ratio, which can be due to the combined effect of the
O-containing groups and nonproportional effects of alkali and alkaline
earth metallic species. The area ratio of the G (graphite) band to
all the bands (<i>A</i><sub>G</sub>/<i>A</i><sub>all</sub>) and that of the valley between D (disordered) and G bands
to the D band (<i>A</i><sub>GR</sub>/<i>A</i><sub>D</sub> and <i>A</i><sub>(GR+VL+VR)</sub>/<i>A</i><sub>D</sub>) had been found useful in evaluating the evolution of
the char structure. An increase in <i>A</i><sub>G</sub>/<i>A</i><sub>all</sub> seemed to suggest the increasing aromatization
of the chars. The increase in <i>A</i><sub>GR</sub><i>/A</i><sub>D</sub> and <i>A</i><sub>(GR+VL+VR)</sub><i>/A</i><sub>D</sub> implied the generation of more smaller
(3–5 rings) aromatic ring structures and the elimination of
lager (no less than 6 rings) aromatic ring systems in the char samples
as the EFR ratio increasing
Demographic Characteristics, Etiology, and Comorbidities of Patients with Cushing’s Syndrome: A 10-Year Retrospective Study at a Large General Hospital in China
Purpose. To investigate the demographic characteristics, etiology, and comorbidities of Cushing’s syndrome (CS) patients at a large medical center in China. Methods. Records on CS patients discharged from 2008 to 2017 were retrieved from the hospital discharge abstract database (DAD) using ICD-10 codes. Demographic characteristics, etiology, and comorbidity data were analyzed. Results. Cushing’s disease (CD) accounted for 63.0% of CS patients, followed by adrenocortical adenoma (ACA) (20.9%), primary bilateral macronodular adrenal hyperplasia (BMAH) (6.2%), ectopic ACTH syndrome (EAS) (5.9%), primary pigmented nodular adrenocortical disease (PPNAD) (1.8%), and adrenocortical carcinoma (ACC) (1.0%). CD, ACA, ACC, and PPNAD presented marked preponderances in women (4.1 : 1, 10.5 : 1, 4.3 : 1, and 2.3 : 1, respectively), while BMAH (59.8%) and EAS (51.0%) showed slightly higher preponderances in men. CD patients were younger than ACA and EAS patients (36.1±12.9 years vs. 39.4±12.7 years and 36.1±12.9 years vs. 41.0±15.8, P<0.001); PPNAD patients were the youngest (24.2±10.8 years, P<0.001), and BMAH patients were the oldest (51.3±9.9 years, P<0.001). Hypertension, diabetes mellitus, osteoporosis without fractures, osteoporotic fractures, dyslipidemia, and fatty liver occurred more frequently in CD patients than in ACA patients (P<0.001 for all). Osteoporotic fractures were observed more frequently in PPAND than in ACA (26.7% vs. 9.0%, P<0.001) and BMAH (26.7% vs. 4.9%, P<0.001) patients. EAS patients had more severe and diverse comorbidities, with higher prevalences of hypokalemia (52.0%), diabetes mellitus (61.2%), and osteoporotic fractures (28.6%). When adjusted for age, male CD patients were associated with hypertension (OR = 2.266, 95% CI: 1.524–3.371, and P<0.001), osteoporotic fractures (OR = 2.274, 95% CI: 1.568–3.298, and P<0.001), fatty liver (OR = 1.435, 95% CI: 1.028–2.003, and P=0.034), and hypokalemia (OR = 1.944, 95% CI: 1.280–2.951, and P=0.002). Conclusions. The proposed method efficiently evaluates CS patients’ epidemiological profiles using hospital DADs with ICD-10 codes and thus may enrich the limited epidemiological data and contribute to clinical practice for CS