Natural product analysis has gained wide attention in recent years, especially for herbal medicines, which contain complex ingredients and play a significant clinical role in the therapy of numerous ...diseases. The constituents of natural products are usually found at low concentrations, and the matrices are complex. Thus, the extraction of target compounds from natural products before analysis by analytical instruments is very significant for human health and its wide application. The commonly used traditional extraction methods are time‐consuming, using large amounts of sample and organic solvents, as well as expensive and inefficient. Recently, microextraction techniques have been used for natural product extraction to overcome the disadvantages of conventional extraction methods. In this paper, the successful applications of and recent developments in microextraction techniques including solvent‐based and sorbent‐based microextraction methods, in natural product analysis in recent years, especially in the last 5 years, are reviewed for the first time. Their features, advantages, disadvantages, and future development trends are also discussed.
Left ventricular (LV) myocardial strain impairment has been demonstrated in hypertension despite normal LV ejection fraction (LVEF); however, limited data exist on any difference in results between ...genders. The aim of this study was to investigate the impact of gender on LV deformation in patients with essential hypertension. This was a cross‐sectional study, in which 94 patients (47 men and 47 women) with essential hypertension and 62 age‐ and gender‐matched controls (31 men and 31 women) were enrolled. A 3.0 T/two‐dimensional balanced steady‐state free precession cine, late gadolinium enhancement was used. The LV endocardial and epicardial contours were drawn by radiologists, then LV volumes, mass, function, and myocardial strain, including peak global radial (GRS), circumferential (GCS), and longitudinal strain (GLS) were automatically calculated. Chi‐square test, Student's t‐test, general linear model analysis, univariate linear regression analysis, stepwise multivariate linear regression analysis, and intraclass correlation coefficient analysis were performed. Women had significantly higher magnitudes of LV GRS, GCS, and GLS than men in both patients and controls (all p < 0.05). In the overall patients, LV GLS was significantly reduced compared with controls (p < 0.05), while GRS and GCS were preserved (p = 0.092 and 0.27, respectively). Compared with their counterpart controls, LV GRS, GCS, and GLS (all p < 0.05) were significantly reduced in hypertensive men, while only GLS (p < 0.05) was reduced in hypertensive women. Male gender and its interaction with hypertension were associated with higher LV mass and volume, decreased LV GRS, GCS, and GLS compared with hypertensive women. Multivariate analyses revealed that gender and LVEF were independently associated with GRS, GCS, and GLS (all p < 0.001) in hypertension. LV deformation is significantly reduced in hypertension, and gender may influence the response of LV deformation to hypertension, with men suffering more pronounced subclinical myocardial dysfunction.
Level of Evidence
3
Technical Efficacy Stage
3
Metabolic syndrome (MetS) is associated with worse prognosis in patients with myocardial infarction (MI). However, it is unclear how MetS in MI patients is associated with left atrial (LA) and left ...ventricular (LV) deformation.
To determine the effect of MetS on LA and LV deformation and atrioventricular interactions in MI patients.
Retrospective.
One hundred eighty-one MI patients (73 MetS+ and 108 MetS-), 107 age- and sex-matched controls (49 MetS+ and 58 MetS-).
3.0 T/balanced steady-state free precession (SSFP)/segmented phase-sensitive inversion recovery SSFP sequence.
LA strain and strain rates (reservoir, conduit, and active), left atrioventricular coupling index (LACI), and LV geometry and radial, circumferential and longitudinal global peak strains (PS) were compared among groups.
Two-way analysis of variance, Spearman and Pearson's correlation coefficients, and multivariable linear regression analysis. P value <0.05 indicated statistical significance.
Compared with controls, the MI patients with or without MetS showed impaired LA function (reservoir, conduit, and active) and LV deformation (radial, circumferential, and longitudinal PS) and higher LACI. The MetS+ group had lower LA reservoir and conduit function and LV deformation than MetS- group. The MetS-MI interaction was not statistically significant. Furthermore, multivariable linear regression showed that MetS was independently associated with LA and LV deformation (β = -0.181 to -0.209) in MI patients; LA function was independently associated with LV circumferential PS (β = 0.230 to 0.394) and longitudinal PS (β = 0.189 to 0.420), and LA passive strain and strain rate were negatively associated with LV mass (β = -0.178 and -0.298).
MetS may be associated with the LA and LV dysfunction in MI patients. Impaired LV deformation and LV hypertrophy are independently associated with LA dysfunction in MI patients, and the MI patients have higher LACI than controls, suggesting atrioventricular interaction alterations.
4 TECHNICAL EFFICACY: 3.
An on-line cyclodextrin assisted sweeping-micellar electrokinetic chromatography (CD assisted sweeping-MEKC) was developed for the simultaneous separation and concentration of four neutral analytes ...(erianin, dendrophenol, naringenin and scoparone) in Dendrobium officinale Kimura et Migo (D. officinale). The D. officinale was directly determined by this on-line stacking method after simple extraction and dilution. The optimized background solution (BGS) was 50 mM phosphoric acid (PA) containing 100 mM SDS and 30% (v/v) methanol. The best separation and concentration performance of analytes dissolved in 90 mM CD and 100 mM PA was achieved in a short analysis time when injected at 50 mbar for 100 s. Compared with conventional sweeping-MEKC and MEKC method, significant improvement in enrichment efficiency was achieved by using this proposed method. A series of validation studies of the present method was performed under the optimal conditions. Good linearities were obtained with the correlation coefficients in the range of 0.994–0.999, the detection limits were ranged from 13 to 40 ng/mL. Sensitivity enhancement factors (SEFs) were in the range of 28.5–46.8 compared with traditional injection (injection time 3 s). Therefore, the proposed method was successfully applied for the separation and concentration of neutral analytes in real samples.
Display omitted
•An on-line CD assisted sweeping-MEKC method is developed for separation and concentration of neutral analytes.•Satisfactory resolution and enrichment efficiency are achieved in a short analysis time.•Compared with conventional sweeping-MEKC and MEKC method, the proposed method shows higher enrichment efficiency.
Type 2 diabetes mellitus (T2DM) increases the risks of heart failure and mortality in patients with hypertension, however the underlying mechanism is unclear. This study aims to investigate the ...impact of coexisting T2DM on left ventricular (LV) deformation and myocardial perfusion in hypertensive individuals.
Seventy hypertensive patients without T2DM HTN(T2DM-), forty patients with T2DM HTN(T2DM+) and 37 age- and sex-matched controls underwent cardiac magnetic resonance examination. Left ventricular (LV) myocardial strains, including global radial (GRPS), circumferential (GCPS) and longitudinal peak strain (GLPS), and resting myocardial perfusion indices, including upslope, time to maximum signal intensity (TTM), and max signal intensity (MaxSI), were measured and compared among groups by analysis of covariance after adjusting for age, sex, body mass index (BMI) and heart rate followed by Bonferroni's post hoc test. Backwards stepwise multivariable linear regression analyses were performed to determine the effects of T2DM on LV strains and myocardial perfusion indices in patients with hypertension.
Both GRPS and GLPS deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM+) group; GCPS in HTN(T2DM+) group was lower than those in both HTN(T2DM-) and control groups. Compared with controls, HTN(T2DM-) group showed higher myocardial perfusion, and HTN(T2DM+) group exhibited lower perfusion than HTN(T2DM-) group and controls. Multiple regression analyses considering covariates of systolic blood pressure, age, sex, BMI, heart rate, smoking, indexed LV mass and eGFR demonstrated that T2DM was independently associated with LV strains (GRPS: p = 0.002, model R
= 0.383; GCPS: p < 0.001, model R
= 0.472; and GLPS: p = 0.002, model R
= 0.424, respectively) and perfusion indices (upslope: p < 0.001, model R
= 0.293; TTM: p < 0.001, model R
= 0.299; and MaxSI: p < 0.001, model R
= 0.268, respectively) in hypertension. When both T2DM and perfusion indices were included in the regression analyses, both T2DM and TTM were independently associated with GRPS (p = 0.044 and 0.017, model R
= 0.390) and GCPS (p = 0.002 and 0.001, model R
= 0.424), and T2DM but not perfusion indices was independently associated with GLPS (p = 0.002, model R
= 0.424).
In patients with hypertension, T2DM had an additive deleterious effect on subclinical LV systolic dysfunction and myocardial perfusion, and impaired myocardial perfusion by coexisting T2DM was associated with deteriorated LV systolic dysfunction.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A rapid, simple, and efficient sample extraction method based on micro‐matrix‐solid‐phase dispersion (micro‐MSPD) was applied to the extraction of polyphenols from pomegranate peel. Five target ...analytes were determined by ultra‐HPLC coupled with Q‐TOF/MS. Carbon molecular sieve (CMS) was firstly used as dispersant to improve extraction efficiency in micro‐MSPD. The major micro‐MSPD parameters, such as type of dispersant, amount of dispersant, grinding time, and the type and the volume of elution solvents, were studied and optimized. Under optimized conditions, 26 mg of pomegranate peel was dispersed with 32.5 mg of CMS, the grinding time was selected as 90 s, the dispersed sample was eluted with 100 μL of methanol. Results showed that the proposed method was of good linearity for concentrations of analytes against their peak areas (coefficient of determination r2 > 0.990), the LOD was as low as 3.2 ng/mL, and the spiking recoveries were between 88.1 and 106%. Satisfactory results were obtained for the extraction of gallic acid, punicalagin A, punicalagin B, catechin, and ellagic acid from pomegranate peel sample, which demonstrated nice reliability and high sensitivity of this approach.
A simple, rapid and eco-friendly approach based on matrix solid-phase dispersion microextraction (MSPDM) followed by ultrahigh performance liquid chromatography coupled with electrochemical detection ...(UHPLC-ECD) was presented for the microextraction and determination of six phenolic acids in a plant preparation (Danshen tablets). The parameters that influenced the extraction performance of phenolic acids were investigated and optimized. The optimal MSPDM conditions were determined as follows: sorbent, using graphene nanoplatelets with sample/sorbent ratio of 1:1, grinding time set at 60 s, and 0.2 mL of water as elution solvent. Under the optimum conditions, the validation experiments indicated that the proposed method exhibited good linearity (r
≥ 0.9991), excellent precision (RSD ≤ 4.57%), and satisfactory recoveries (82.34-98.34%). The limits of detection were from 1.19 to 4.62 ng/mL for six phenolic acids. Compared with other reported methods, this proposal required less sample, solvent and extraction time. Consequently, the proposed method was successfully used to the extraction and determination of phenolic acids in Danshen tablets.
Previous studies reported that there was right ventricular (RV) systolic dysfunction in patients with hypertension. The aim of this study was to evaluate the impact of type 2 diabetes mellitus (T2DM) ...on RV systolic dysfunction and interventricular interactions using cardiac magnetic resonance feature tracking (CMR-FT) in patients with essential hypertension.
Eighty-five hypertensive patients without T2DM HTN(T2DM -), 58 patients with T2DM HTN(T2DM +) and 49 normal controls were included in this study. The biventricular global radial, circumferential and longitudinal peak strains (GRS, GCS, GLS, respectively) and RV regional strains at the basal-, mid- and apical-cavity, were calculated with CMR-FT and compared among controls and different patient groups. Backward stepwise multivariable linear regression analyses were used to determine the effects of T2DM and left ventricular (LV) strains on RV strains.
The biventricular GLS and RV apical longitudinal strain deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM +) groups. RV middle longitudinal strain in patient groups were significantly reduced, and LV GRS and GCS and RV basal longitudinal strain were decreased in HTN(T2DM +) but preserved in HTN(T2DM-) group. Multivariable regression analyses adjusted for covariates demonstrated that T2DM was independently associated with LV strains (LV GRS: β = - 4.278, p = 0.004, model R
= 0.285; GCS: β = 1.498, p = 0.006, model R
= 0.363; GLS: β = 1.133, p = 0.007, model R
= 0.372) and RV GLS (β = 1.454, p = 0.003, model R
= 0.142) in hypertension. When T2DM and LV GLS were included in the multiple regression analysis, both T2DM and LV GLS (β = 0.977 and 0.362, p = 0.039 and < 0.001, model R
= 0.224) were independently associated with RV GLS.
T2DM exacerbates RV systolic dysfunction in patients with hypertension, which may be associated with superimposed LV dysfunction by coexisting T2DM and suggests adverse interventricular interactions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introduction
The main active components in hawthorn leaves possess various biological activities such as anti‐inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to ...develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves.
Objective
To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves.
Methods
In this study, a microwave‐assisted reaction and extraction (MARE) combined with ultra‐high‐performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time‐of‐flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised.
Results
The optimal conditions were as follows: 0.1 g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01 g, extraction time was 10 min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5–37.7 ng/mL. The average recoveries ranged from 80.22% to 93.27%.
Conclusion
In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.
High extraction efficiencies and sensitivities of target compounds were achieved. The proposed method is a green, simple, easy operation, time‐saving and effective approach.
A novel dispersive micro‐SPE method with trace poly‐β‐CD wrapped multiwalled carbon nanotubes as sorbents was applied to extract flavonoids in honey samples. The analytes were then determined by CE ...with LED‐induced fluorescence detection. The influencing parameters, such as the sorbent concentration, extraction time, and eluent type, were properly optimized. The established method had the advantages of simplicity, low consumption of sorbent amount (0.009 mg) and organic solvent (100 μL), and high sensitivity, meeting the principle of green chemistry. Under the optimum conditions, the sorbents allowed the extraction and preconcentration of the flavonoids with enrichment factors in the range from 78 to 166. The recovery study performed at two different fortification levels provided an average recovery >91%. LODs for all the compounds ranged from 0.07 to 17.99 ng/mL. These results demonstrated that the proposed method could be used as a convenient and efficient extraction technique for analysis of flavonoids in different honey matrices.
PDF
