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1.
Biomacromolecules ; 24(12): 5578-5588, 2023 12 11.
Article in English | MEDLINE | ID: mdl-37934174

ABSTRACT

Biobased films were synthesized from starch oleate (DS = 2.2) cross-linked with polyethylene glycol with Mn = 2000 and 1000 g · mol-1, and ethylene glycol, all of which were esterified with either lipoic acid (LA) or 3-mercaptopropionic acid (MPA). Cross-linking was achieved through a UV-initiated thiol-ene click, and confirmed by Fourier transform infrared spectroscopy and rheometry. The films exhibit higher degradation temperatures, and an increased degree of crystallinity as cross-linker length increased. The introduction of MPA-based cross-linkers resulted in hydrophilic films, while the contact angle was barely affected by the addition of LA-based cross-linkers. A reduction in maximum strength upon introducing the cross-linkers was observed, while an increase in elongation was observed for most of the LA-based cross-linkers. Our results demonstrate the potential for tuning the mechanical and thermal properties of starch-based films through the cross-linker choice, with some formulations exhibiting increased flexibility that may be well suited for packaging applications.


Subject(s)
Starch , Sulfhydryl Compounds , Sulfhydryl Compounds/chemistry , Starch/chemistry , Oleic Acid , Polyethylene Glycols/chemistry , 3-Mercaptopropionic Acid/chemistry
2.
Polym Chem ; 14(44): 5014-5020, 2023 Nov 14.
Article in English | MEDLINE | ID: mdl-38013676

ABSTRACT

Dynamic covalent networks (DCNs) are materials that feature reversible bond formation and breaking, allowing for self-healing and recyclability. To speed up the bond exchange, significant amounts of catalyst are used, which creates safety concerns. To tackle this issue, we report the synthesis of a lipoic acid-based vitrimer-like elastomer (LAVE) by combining (i) ring-opening polymerization (ROP) of lactones, (ii) lipoic acid modification of polylactones, and (iii) UV crosslinking. The melting temperature (Tm) of LAVE is below room temperature, which ensures the elastic properties of LAVE at service temperature. By carefully altering the network, it is possible to tune the Tm, as well as the mechanical strength and stretchability of the material. An increase in polylactone chain length in LAVE was found to increase strain at break from 25% to 180% and stress at break from 0.34 to 1.41 MPa. The material showed excellent network stability under cyclic strain loading, with no apparent hysteresis. The introduction of disulfide bonds allows the material to self-heal under UV exposure, extending its shelf life. Overall, this work presents an environmentally friendly approach for producing a sustainable elastomer that has potential for use in applications such as intelligent robots, smart wearable technology, and human-machine interfaces.

3.
Clin Ther ; 45(11): e222-e233, 2023 11.
Article in English | MEDLINE | ID: mdl-37852812

ABSTRACT

PURPOSE: To date, no study has demonstrated the role of transdermal 17ß-estradiol + norethisterone acetate on all of the risk factors for cardiovascular disease in postmenopausal women. To overcome this knowledge gap, a systematic review and meta-analysis were conducted to determine the effects of this combination treatment on BMI, body weight, waist/hip ratio, fibrinogen, factor VII, lipoprotein(a), fasting blood sugar, insulin, HbA1c, TG, LDL-C, HDL-C, and TC in postmenopausal women. METHODS: PubMed/Medline, SCOPUS, Web of Science, Embase, and Google Scholar were searched for relevant articles published between the inception of each database and April 6, 2023. The sample size and mean (SD) were used to calculate overall effect size using a random-effects model. FINDINGS: A total of 10 articles with 14 arms were included in the meta-analysis. On pooled analysis of effect size, fibrinogen (weighted mean difference [WMD], -0.18 g/L; 95% CI, -0.25 to -0.10), factor VII (WMD, -9.58; 95% CI, -12.51 to -6.64), LDL-C (WMD, -13.09 mg/dL; 95% CI, -18.48 to -7.71), and TC (WMD, -12.61 mg/dL; 95% CI, -18.11 to -7.12) were significantly affected with the use of transdermal 17ß-estradiol + norethisterone acetate (all, P < 0.001), but effects on lipoprotein(a), TG, HDL-C, fasting blood sugar, insulin, HbA1c, BMI, body weight, and waist/hip ratio were not significant. IMPLICATIONS: Based on the findings from the present systematic review and meta-analysis, it was concluded that transdermal administration of 17ß-estradiol + norethisterone acetate had beneficial impacts on fibrinogen, factor VII, LDL-C, and TC, suggesting a possible application in the reduction of cardiovascular disease risk.


Subject(s)
Blood Glucose , Cardiovascular Diseases , Female , Humans , Norethindrone Acetate , Cholesterol, LDL , Administration, Cutaneous , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Postmenopause , Factor VII , Body Weight , Risk Factors , Heart Disease Risk Factors , Insulin , Estradiol/adverse effects , Fibrinogen , Lipoprotein(a) , Randomized Controlled Trials as Topic
4.
Medicine (Baltimore) ; 102(31): e34476, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37543801

ABSTRACT

Taohong Siwu Decoction (THSWD) was widely used for the treatment of varicocele-associated male infertility. However, the pharmacological mechanism of action is not completely clear. Therefore, network pharmacology and molecular docking were performed to explore potential mechanism of THSWD in the treatment of varicocele-associated male infertility. The Traditional Chinese Medicine Systems Pharmacology (TCMSP), Swiss Target Prediction, and GeneCards were used to retrieve candidate compounds, action targets, and disease-related targets. The construction of the protein-protein interaction (PPI) network and the screening of core genes were completed by the STRING and Cytoscape 3.9.1, respectively. The DAVID was used to obtain results of gene ontology function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The Mcule analysis platform was used to perform molecular docking. There were a total of 53 candidate compounds and 782 relevant targets in THSWD. There were 45 common targets between THSWD, varicocele, and male infertility, and 23 core genes were found in the PPI network. Biological processes involved response to hypoxia, regulation of blood pressure, cellular response to hypoxia, and regulation of the nitric oxide biosynthetic process. Furthermore, the KEGG pathway enrichment analysis showed that the common targets mainly regulated the disease of varicocele-associated male infertility through the HIF-1 signaling pathway, PI3K-Akt signaling pathway, Relaxin signaling pathway, and TNF signaling pathway. Finally, the molecular docking showed that luteolin, quercetin, and kaempferol had good intercalation with major targets. As predicted by network pharmacology, THSWD regulated varicocele-associated male infertility through multiple compounds and targets, and its mechanism was closely related to inflammatory response, reactive oxygen species damage, and function of blood vessels.


Subject(s)
Drugs, Chinese Herbal , Varicocele , Humans , Male , Molecular Docking Simulation , Network Pharmacology , Phosphatidylinositol 3-Kinases , Varicocele/complications , Varicocele/drug therapy , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Medicine, Chinese Traditional , Hypoxia
5.
Polymers (Basel) ; 15(11)2023 May 26.
Article in English | MEDLINE | ID: mdl-37299266

ABSTRACT

Starch oleate (degree of substitution = 2.2) films were cast and crosslinked in the presence of air using UV curing (UVC) or heat curing (HC). A commercial photoinitiator (CPI, Irgacure 184) and a natural photoinitiator (NPI, a mixture of biobased 3-hydroxyflavone and n-phenylglycine) were used for UVC. No initiator was used during HC. Isothermal gravimetric analyses, Fourier Transform Infrared (FTIR) measurements, and gel content measurements revealed that all three methods were effective in crosslinking, with HC being the most efficient. All methods increased the maximum strengths of film, with HC causing the largest increase (from 4.14 to 7.37 MPa). This is consistent with a higher degree of crosslinking occurring with HC. DSC analyses showed that the Tg signal flattened as film crosslink densities increased, even disappearing in the case of HC and UVC with CPI. Thermal gravimetric analyses (TGA) indicated that films cured with NPI were least affected by degradation during curing. These results suggest that cured starch oleate films could be suitable for replacing the fossil-fuel-derived plastics currently used in mulch films or packaging applications.

6.
Carbohydr Polym ; 316: 121043, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37321736

ABSTRACT

Oleic acid and 10-undecenoic acid were used to esterify corn, tapioca, potato and a waxy potato starch, with a maximum degree of substitution of 2.4 and 1.9 respectively. The thermal and mechanical properties were investigated as a function of the amylopectin content and Mw of starch, and by the fatty acid type. All starch esters had an improved degradation temperature regardless of their botanical origin. While the Tg did increase with increasing amylopectin content and Mw, it decreased with increasing fatty acid chain length. Moreover, films with different optical appearances were obtained by varying the casting temperature. SEM and polarized light microscopy showed that films cast at 20 °C had porous open structures with internal stress, which was absent when cast at higher temperatures. Tensile test measurements revealed that films had a higher Young's modulus when containing starch with a higher Mw and amylopectin content. Besides that, starch oleate films were more ductile than starch 10-undecenoate films. In addition, all films were resistant to water at least up to one month, while some light-induced crosslinking took place. Finally, starch oleate films showed antibacterial properties against Escherichia coli, whereas native starch and starch 10-undecenoate did not.


Subject(s)
Amylose , Starch , Starch/chemistry , Amylose/chemistry , Amylopectin/chemistry , Temperature , Molecular Weight , Esters , Oleic Acid
7.
ACS Appl Mater Interfaces ; 15(3): 4398-4407, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36514844

ABSTRACT

Elastomer-based wearables can improve people's lives; however, frictional wear caused by manipulation may pose significant concerns regarding their durability and sustainability. To address the aforementioned issue, a new class of advanced scalable supersoft elastic transparent material (ASSETm) is reported, which offers a unique combination of scalability (20 g scale), stretchability (up to 235%), and enzymatic degradability (up to 65% in 30 days). The key feature of our design is to render native dextrin hydrophobic, which turns it into a macroinitiator for bulk ring-opening polymerization. Based on ASSETm, a self-powered touch sensor (ASSETm-TS) for touch sensing and non-contact approaching detection, possessing excellent electrical potential (up to 65 V) and rapid response time (60 ms), is fabricated. This work is a step toward developing sustainable soft electronic systems, and ASSETm's tunability enables further improvement of electrical outputs, enhancing human-interactive applications.

8.
Carbohydr Polym ; 292: 119649, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-35725159

ABSTRACT

This work presents a series of starch esters synthesized via 1,5,7-triazabicyclo[4.4.0]-dec-5-ene (TBD) catalyzed transesterifications in dimethyl sulfoxide (DMSO). The reaction was performed with saturated and unsaturated fatty acids (8, 11, and 18 carbon atoms). The degree of substitution (DS) was raised by purging the reaction flask with nitrogen instead of simply performing the reaction under a nitrogen atmosphere. The increase of DS was most obvious for long-chain fatty acids, as an almost complete DS was observed for starch stearate (2.8) and starch oleate (2.7). The products were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and X-ray diffraction. Starch esters from unsaturated fatty acids have a lower Tg than their saturated analogues. Moreover, contact angle and moisture uptake measurements showed increased hydrophobicity for all starch esters in comparison to pristine starch. Our results show a more efficient method for synthesizing a biobased material that steers into the direction of a material that could replace conventional plastics.


Subject(s)
Esters , Starch , Esterification , Nitrogen , Oleic Acid , Starch/chemistry
9.
Opt Express ; 30(7): 10428-10442, 2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35473010

ABSTRACT

An all-photonic approach of microwave waveforms generation and transformation is proposed and experimentally demonstrated. From the perspective of envelope function operation in time domain, an initial triangular waveform is transformed into square waveform and sawtooth (or reversed-sawtooth) waveform via two types of differentiators, respectively. In addition, by using a SOA as a multiplier, both bright and dark parabolic pulses are achieved, which are further transformed into sawtooth (or reversed-sawtooth) waveform by taking the first derivative operation. The feasibility of the system is verified by theoretical analysis and simulation. In experiment, all of the expected results are successfully demonstrated and agree with the theoretical analysis well. This scheme provides a novel access to implement all-optical microwave waveforms generation, transformation, signal processing and computing.

10.
Breast ; 54: 264-271, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33212422

ABSTRACT

BACKGROUND: Early integration of palliative care (PC) for patients with advanced cancer has been recommended to improve quality of care. This study aims to describe prevalence, temporal trend and predictors of PC use in metastatic breast cancer (mBCa) patients receiving critical care therapies (CCT; included invasive mechanic ventilation, percutaneous endoscopic gastrostomy tube, total parenteral nutrition, tracheostomy and dialysis). METHODS: The National Inpatient Sample was queried for mBCa patients receiving CCT between 2005 and 2014. Annual percent changes (APC) were calculated for PC prevalence in the overall cohort and subgroups. Multivariable logistic analysis was used to explore predictors of PC use. RESULTS: Of 5833 mBCa patients receiving CCT, 880 (15.09%) received PC. Rate of PC use increased significantly from 2.53% in 2005 to 25.96% in 2014 (APC: 35.75%; p < 0.0001). Higher increase in PC use was observed in South (from 0.65% to 27.11%; APC: 59.42%; p < 0.0001), medium bedsize hospitals (from 3.75% to 26.05%; APC: 38.16%; p = 0.0006) and urban teaching hospitals (from 4.13% to 29.86%; APC: 37.33%; p = 0.0005). Multivariable analysis revealed that year interval, urban teaching hospitals, and invasive mechanical ventilation were associated with increased PC use, while primary diagnosis of gastrointestinal disorders, fractures, metastatic sites from lymph nodes and tracheostomy were associated with lower PC use. CONCLUSIONS: PC use in mBCa patients receiving CCT increases significantly over the period. However, it still remains low. Efforts to illustrate disparities in PC use are needed to improve quality of care for mBCa patients receiving CCT, especially for those hospitalized in rural and nonteaching hospitals.


Subject(s)
Breast Neoplasms/therapy , Healthcare Disparities/trends , Inpatients/statistics & numerical data , Palliative Care/trends , Patient Acceptance of Health Care/statistics & numerical data , Aged , Critical Care/statistics & numerical data , Databases, Factual , Female , Humans , Logistic Models , Middle Aged , Prevalence , Quality of Health Care/trends , United States/epidemiology
11.
J Food Sci ; 85(1): 57-64, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31769514

ABSTRACT

This study investigated effects of fermentation on compositions, color, and functional properties of gelatinized potato flours from Atlantic and Kexin No.1 cultivars. Atlantic flour (AF) and Kexin No.1 flour (KF) were fermented using 1% yeast concentration, respectively. Fermentation further improved the nutritional and physicochemical features of gelatinized potato flours by means of increased protein and ash contents, and decreased the levels of moisture, lipid, soluble amylose, amylopectin, and total starch. The lightness and whiteness of potato flours were enhanced with the increase in fermentation time. There are gradual increases in water absorption index, emulsifying capacity and emulsifying stability of potato flours during fermentation. However, bulk density of them slightly reduced with the increase in fermentation time. In addition, fermentation has no significant effect on freeze-thaw stability of gelatinized potato flours. These results indicate that yeast fermentation could enhance certain processing characteristics of potato flours and improve the applicability of them in food formulations. PRACTICAL APPLICATION: Lately, China has started national project regarding the use of potato flour in foods. However, due to dark color and low protein content of potato flours, their application in food formulations was limited. This study analyzed the possible mechanisms by which yeast fermentation improved the nutritional and functional characteristics of Atlantic flour (AF) and Kexin No. 1 flour (KF). From applications standpoint, findings of this study could provide knowledge on the selection of potato flours for various food formulations.


Subject(s)
Flour/analysis , Solanum tuberosum/chemistry , Yeasts/metabolism , Amylose/chemistry , Amylose/metabolism , China , Color , Fermentation , Flour/microbiology , Gels/chemistry , Gels/metabolism , Solanum tuberosum/metabolism , Solanum tuberosum/microbiology , Starch/chemistry , Starch/metabolism
12.
Food Chem ; 271: 62-69, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30236724

ABSTRACT

The lignin isolated from C. edulis ker residues showed a significant activating effect on α-amylase. Further studies revealed that the isolated lignin formed a 1:1 complex with α-amylase through hydrogen bonding and quenched fluorescence of α-amylase with a static quenching procedure. Binding with lignin led to conformational and granular size changes of α-amylase. Two-dimensional nuclear Overhauser spectroscopy (2D-NOESY) spectra suggested that OH in G units and ß-O-4 structure were the major binding sites of lignin on the α-amylase molecule. Molecular docking studies indicated that the binding residue on α-amylase for lignin was not the same as for chloride ions, and the major binding force was hydrogen bonding. Furthermore, the docking results also showed the structural change of lignin induced by α-amylase. Thus, this work provided a new insight into the interaction between lignin from Canna edulis ker residues and α-amylase, which may be beneficial to apply lignin in the food industry.


Subject(s)
Lignin/chemistry , Molecular Docking Simulation/methods , Zingiberales/chemistry , Zingiberales/enzymology , alpha-Amylases/metabolism , Binding Sites , Hydrogen Bonding , Kinetics
13.
Carbohydr Polym ; 196: 474-482, 2018 Sep 15.
Article in English | MEDLINE | ID: mdl-29891321

ABSTRACT

To better understand the effects of high pressure processing on potato peel waste pectins, the structural characteristics, physicochemical properties, and morphological features of the pectin treated with high hydrostatic pressure (HHP) and high pressure homogenization (HPH) at 200 MPa for 5 min were studied. The potato peel waste pectins subjected to high pressure treatments exhibited increased galacturonic acid contents as well as decreased esterification degree, (Gal + Ara)/Rha ratio, and molecular weight. Furthermore, the potato peel waste pectins treated with high pressure had an increased viscosity and improved emulsifying properties. The morphological features, determined by atomic force microscopy, shown the degradation of side chains of the pectin induced by high pressure treatments. The results suggest that high pressure processing is an efficient technique to modify pectin from potato peel waste to a thickener or stabilizer agent, but high pressure homogenization shows a better effect.

14.
J Food Sci ; 83(5): 1311-1320, 2018 May.
Article in English | MEDLINE | ID: mdl-29660758

ABSTRACT

Antifreeze peptides can protect living organisms from low temperatures by preventing damage or killing due to ice crystal formation between cells. Therefore, antifreeze peptides can be used as a low temperature protectant for cryopreservation of cells and tissues, and also in food production. In this study, a recombinant SF-P gene was constructed and inserted into pNZ8149 to construct a food grade expression vector, which was then electroporated into Lactococcus lactis NZ3900. The expression of the target protein was induced using Nisin, and the optimal expression condition was determined to be a pH of 6.0, Nisin concentration of 25 ng/mL, temperature of 37 °C, and incubation time of 6 hr. Compared to the strain NZ3900 and the recombinant strain SF-P1 without addition of Nisin, the recombinant strain SF-P2 showed the highest cell survival and thermal hysteresis activity, and had a reduction in the changes of activities of extracellular and intracellular lactate dehydrogenase and ß-galactosidase after freezing. Moreover, analysis by SEM showed that SF-P2 cells were more completely and regularly shaped than other strains, displayed no obvious leakage of cell contents, and had an intact boundary between cells after freezing. These results indicate that the recombinant strain SF-P2 has a protective effect against freezing. This paper presents a food grade expression system for an antifreeze peptide SF-P using L. lactis as a host, and shows that the intracellular expression of antifreeze peptide could protect the cellular integrity and physiological functions of L. lactis. PRACTICAL APPLICATION: The recombinant Lactococcus lactis with intracellular expression of antifreeze peptides SF-P could reduce the damage of bacteria cells induced by freezing or freeze drying, so, it could be applied in the process of freezing food without separation, such as the manufacture of yoghurt ice cream, frozen dough, and so on.


Subject(s)
Antifreeze Proteins/metabolism , Cryoprotective Agents/metabolism , Freezing , Lactococcus lactis/metabolism , Animals , Antifreeze Proteins/genetics , Antifreeze Proteins/pharmacology , Cryoprotective Agents/pharmacology , Fermented Foods , Food , Freeze Drying , Humans , L-Lactate Dehydrogenase/metabolism , Lactococcus lactis/growth & development , Lactococcus lactis/physiology , Nisin/pharmacology , Recombinant Proteins/genetics , Siphonaptera/genetics , Species Specificity , beta-Galactosidase/metabolism
15.
J Food Sci ; 82(5): 1247-1253, 2017 May.
Article in English | MEDLINE | ID: mdl-28339113

ABSTRACT

Compared to synthetic antioxidants, tea polyphenols (TPs) has its own advantages in edible oil industry, however, the hydrophilic properties have restricted its applications. In this study, the ternary phase diagram of TPs-loaded micro-emulsion (ME) system was constructed, in which glyceryl monooleate (GMO), Tween80, linoleic acid as the surfactants, ethanol as the co-surfactant and soybean, corn, sunflower oil as the oil phase, have been used for the preparation of ME. The results indicated that a composition of ME (57.5% oil, 18% Tween80, 18% GMO, 4% Linolic acid, and 2.5% water+ethanol) could dissolve maximum water and could stable for 2 mo at room temperature with an average diameter of 6 to 7 nm, as detected by means of dynamic light scattering (DLS). The loaded of TPs into ME led to an increase of particle size to 15 to 16 nm, due to increased polarity of the water phase. The antioxidant capacity of TPs in ME was characterized by the peroxide value (POV) method. The addition of 1% water phase with 0.1 g/mL TPs could retain the POV at low value for 30 d at accelerating temperature 50 °C. Meanwhile, comparing the three edible oil, ME with corn oil has lower conductivity and higher value of POV during the storage. This work provides an efficient and environmentally friendly approach for the preparation of TPs-loaded ME, which is beneficial to the application of TPs in edible oil.


Subject(s)
Camellia sinensis/chemistry , Polyphenols/chemistry , Antioxidants , Emulsions , Oxidation-Reduction , Particle Size , Surface-Active Agents , Temperature , Water
16.
Int J Biol Macromol ; 93(Pt A): 1210-1216, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27614197

ABSTRACT

Canna starch was annealed at sub-gelatinization temperature (50°C) with different annealing time. Small angle X-ray scattering (SAXS) was used to estimate the ultrastructure of the annealed starches with the combined two-phase lamellar model and one-dimensional correlation function. The results showed that, upon annealing, water preferably swelled the amorphous regions of canna starch granules while maintained the part of crystalline region, resulted in an increase in amorphous thickness (da) and lamellar repeat distance (d). Power law plots indicates that a mass fractal (self-similar) structure was observed in canna starch, and annealing induces a less compact structure compared to native canna starch (NCS). Correlation analysis showed that no correlation was existed between annealing time and lamellar peak area, width of peak, and volume crystallinity. However, due to the initial degradation of the amorphous region, the volume crystallinity increased significantly with the increase of crystalline thickness (dc).


Subject(s)
Starch/chemistry , Zingiberales/chemistry , Linear Models , Temperature
17.
Food Chem ; 188: 632-40, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26041241

ABSTRACT

Starches from five underutilized tubers (canna, potato, Chinese yam, water chestnut, and taro) were extracted to investigate quantitative structure-property relationships (QSPR) in each starch using a combination of X-ray diffraction (XRD) and small-angle X-ray scattering (SAXS). Structural parameters of the tuber starches were determined using the paracrystalline model. Swelling power (SP), water solubility index (WSI), amylose leaching (AML), and thermal properties were also measured. The XRD results indicated that starches from Chinese yam, water chestnut, and taro are C-type starches with relatively high crystallinity (29.23-35.02%). In contrast, canna and potato starches are B-type starches exhibiting lower crystallinity and higher amylose content. The paracrystalline model provided a better fit for the C-type starches than for the B-type starches because the former was highly compressible (indicated by a higher "ß" value). B-type starches, on the other hand, tend to be more rigid along the lamellar repeat direction, requiring the layers to bend to accommodate internal stress. The QSPR analysis showed that three structural parameters, "Ø", "ß", and "Δρu", correlate well with the SP and WSI, and thus can be used to predict certain physicochemical properties.


Subject(s)
Starch/chemistry , Starch/ultrastructure , X-Ray Diffraction/methods , Amylose/analysis , Quantitative Structure-Activity Relationship
18.
Acta Pharmacol Sin ; 36(4): 429-39, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25832423

ABSTRACT

AIM: To investigate the effect of chronic nicotine treatment on vascular function and to identify the underlying mechanisms. METHODS: Adult rats were treated with nicotine (3 mg·kg(-1)·d(-1), sc) for 6 weeks. After the rats were sacrificed, aortic rings were prepared for detecting vascular reactivity, and thoracic aorta and periaortic fat samples were collected for histological and molecular biology studies. RESULTS: Chronic nicotine treatment significantly reduced periaortic fat, and specifically enhanced smooth muscle relaxation without altering the aortic adventitial fat and endothelium function. Pretreatment with the soluble guanylyl cyclase inhibitor ODQ (3 µmol/L) or PKG inhibitor Rp-8-Br-PET-cGMP (30 µmol/L) abolished the nicotine-induced enhancement of smooth muscle relaxation, whereas the cGMP analogue 8-Br-cGMP could mimic the nicotine-induced enhancement of smooth muscle relaxation. However, the chronic nicotine treatment did not alter PKG protein expression and activity in aortic media. CONCLUSION: Chronic nicotine treatment enhances vascular smooth muscle relaxation of rats via activation of PKG pathway.


Subject(s)
Aorta/drug effects , Ganglionic Stimulants/pharmacology , Muscle Relaxation/drug effects , Muscle, Smooth, Vascular/drug effects , Nicotine/pharmacology , Nicotinic Agonists/pharmacology , Vasodilation/drug effects , Animals , Aorta/physiology , Cyclic GMP-Dependent Protein Kinase Type I/metabolism , Fats/metabolism , Ganglionic Stimulants/administration & dosage , Male , Muscle, Smooth, Vascular/physiology , Nicotine/administration & dosage , Nicotinic Agonists/administration & dosage , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects
19.
Zhongguo Zhong Yao Za Zhi ; 39(10): 1880-5, 2014 May.
Article in Chinese | MEDLINE | ID: mdl-25282899

ABSTRACT

In this study, an approach based on triple-color fluorescence probes was developed for screening potential nephro-protective bioactive substances. Three fluorescent probes (i. e. FDA, MTR and Hoechst 33342) were used to label HK-2 cells injured by doxorubicin hydrochloride, and cellular fluorescence images were subsequently acquired and analyzed by a cellular-fluorescence image microscopy platform. The established method was applied to screening 53 components of Carthami Flos, and three components C17, C18 and C19 were found to exhibit nephroprotective effects against doxorubicin hydrochloride induced injury on HK-2 cells. Eight compounds (i. e. hydroxysafflor yellow A, 6-hydroxykaempferol-3-O-rutinoside-6-O-glucoside, 6-hydroxykaempferol-3,6-di-O-gluco-side or 6-hydroxykaempferol-6, 7-di-O-glucoside, 6-hydroxykaempferol-3-O-rutinoside, 6-hydroxykaempferol-3-O-glucoside or 6-hydroxykaempferol-7-O-glucoside, rutin, isoquercetin, and kaempferol-3-O-rutinoside) in components C17, C18 and C19 were preliminarily identified by liquid chromatography-mass spectrometry (LC-MS). Isoquercetin, rutin, kaempferol-3-O-rutinoside, and hydroxysafflor yellow A were confirmed by comparing with reference substances, Further study indicated that these four compounds had moderate nephroprotective effects, while isoquercetin showed a significant nephroprotective effect in a dose-dependent manner. These results suggest that isoquercetin, rutin, kaempferol-3-O-rutinoside and hydroxysafflor yellow A might be the nephroprotective bioactive substances in Carthami Flos.


Subject(s)
Carthamus/chemistry , Drugs, Chinese Herbal/chemistry , Protective Agents/chemistry , Cell Line , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Drugs, Chinese Herbal/pharmacology , Flowers/chemistry , Fluorescent Dyes/chemistry , Humans , Kidney/chemistry , Kidney/cytology , Kidney/drug effects , Protective Agents/pharmacology
20.
Cardiovasc Res ; 102(3): 448-59, 2014 Jun 01.
Article in English | MEDLINE | ID: mdl-24604622

ABSTRACT

AIMS: Endothelial dysfunction is an initial and vascular smooth muscle cell (VSMC) apoptosis, a later step of atherosclerosis. Hypothyroidism accelerates atherosclerosis. However, the early events responsible for this pro-atherosclerotic effect are unclear. METHODS AND RESULTS: Rats were resistant to induction of atherosclerosis by high cholesterol diet alone, but became susceptible in hypothyroid state achieved by administration of propylthiouracil (PTU) for 6 weeks. VSMC dysfunction and apoptosis were obvious within 1 week after PTU treatment, without signs of endothelial dysfunction. This early VSMC damage was caused by hypothyroidism but not the high cholesterol diet. In ApoE knockout mice, PTU-induced hypothyroidism triggered early VSMC apoptosis, increased oxidative stress, and accelerated atherosclerosis development. Thyroid hormone supplementation (T4, 10, or 50 µg/kg) prevented atherogenic phenotypes in hypothyroid rats and mice. In rats, thyroidectomy caused severe hypothyroidism 5 days after operation, which also led to rapid VSMC dysfunction and apoptosis. In vitro studies did not show a direct toxic effect of PTU on VSMCs. In contrast, thyroid hormone (T3, 0.75 µg/L plus T4, 50 nmol/L) exerted a direct protection against VSMC apoptosis, which was reduced by knockdown of TRα1, rather than TRß1 and TRß2 receptors. TRα1-mediated inhibition of apoptotic signalling of JNKs and caspase-3 contributed to the anti-apoptotic action of thyroid hormone. CONCLUSION: These findings provide an in vivo example for VSMC apoptosis as an early trigger of hypothyroidism-associated atherosclerosis, and reveal activation of TRα1 receptors to prevent VSMC apoptosis as a therapeutic strategy in this disease.


Subject(s)
Apoptosis , Atherosclerosis/etiology , Hypothyroidism/complications , Muscle, Smooth, Vascular/pathology , Myocytes, Smooth Muscle/pathology , Animals , Apolipoproteins E/physiology , Cells, Cultured , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle, Smooth, Vascular/drug effects , Myocytes, Smooth Muscle/drug effects , Propylthiouracil/toxicity , Rats , Rats, Sprague-Dawley , Thyroid Hormone Receptors alpha/physiology , Thyroid Hormone Receptors beta/physiology , Thyroid Hormones/deficiency
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