The present work reports on the synthesis of chiral particles consisting of helical polylactide (PLA) and helical substituted polyacetylene, aiming to investigate the chiral synergetic effects of the ...two helical components in enantioselectivity. For this purpose, polylactide with polymerizable terminal alkynyl group was prepared and subsequently used as macromer to copolymerize with chiral alkynyl monomer to form the target particles. SEM images demonstrate that the particles possessed porous structures. Circular dichroism shows that the helical substituted polyacetylene had an influence on the helical screw sense of polylactide chains, thereby affecting the enantioselectivity of the chiral particles in releasing the model chiral drug naproxen. Compared with our earlier study on enantioselectivity of PLA, copolymerizing PLA with chiral alkynyl monomer improves PLA’s enantioselectively discriminating ability in naproxen release and even can reverse the particles’ preferential enantioselectivity in releasing naproxen enantiomers.
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IJS, KILJ, NUK, PNG, UL, UM
Chiral molecularly imprinted polymer microspheres (MIPMs) reported so far are majorly limited to being constructed by using achiral polymer together with chiral template. The present contribution ...reports on a unique type of chiral MIPMs consisting of chirally helical substituted polyacetylene, which are prepared through suspension polymerization by using (a)chiral acetylenics as monomer and chiral Boc-d/l-proline as template. The resulting MIPMs after removing the template show optical activity that is derived from the chirally helical structures of substituted polyacetylene. The microspheres demonstrate enantio-differentiating ability in releasing the enantiopure templates. A complete release of the template provides the chiral MIPMs. Worthy to mention is that the two chiral sources (chirally helical conformation and chiral template configuration) work in a synergistic way, obviously increasing the MIPMs’ enantiodiscrimination ability. The present study develops a strategy for preparing chiral MIPMs, which are expected to find significant applications in chiral separation, enantioselective release of chiral drugs, etc.
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IJS, KILJ, NUK, PNG, UL, UM
Hybrid materials are interesting because they combine the advantages of multiple components in one material entity. This article reports on a new type of chiral porous hybrid particle constructed by ...helical substituted polyacetylene and silica. To prepare the hybrid particles, chirally helical substituted acetylene copolymers containing pendent Si-O-Et groups were first synthesized and subsequently used as macromolecular silane couplers to perform a sol-gel reaction with TEOS. After aging, the designed hybrid particles were fabricated. Phase separation in the sol-gel reaction endowed the hybrid particles with abundant pores. In the resulting hybrid particles, inorganic silica constituted the rigid framework, whereas the organic helical substituted polyacetylene bonded with the framework and offered optical activity. SEM images confirmed the formation of spherical particles with regular morphology and porous structure. Circular dichroism and UV-vis absorption spectra demonstrated that the helical polymer chains had a preferential helicity and considerable optical activity in the hybrid particles. The hybrid materials demonstrated the capability of enantioselectively releasing cinchona alkaloid, which was used to model chiral drugs. The release process was found to be influenced by temperature: low temperature was more favorable for enantio-differentiating release.
Incorporating multi-functions into a single entity can provide various novel materials, well exemplified by interpenetrating polymer networks. In this contribution, we prepared the first chiral ...porous interpenetrating polymer networks (IPNs) by incorporating functional boronic acid-containing polymers to a pre-formed chiral porous framework which was constructed by chirally helical substituted polyacetylenes. The pore size in the resulting chiral IPNs can be tuned by adjusting the content of the boronic acid-containing polymer. Circular dichroism and UV-vis absorption spectra demonstrated that the helical polymer chains in both the pre-formed chiral porous framework and the final IPNs took preferential helicity, which rendered the IPNs with considerable optical activity. The as-prepared IPNs could adsorb glucose through esterification reaction occurring between the boronic acid groups contained in the networks and cis -diol in glucose. More importantly, the successful combination of boronic acid groups with the chiral framework enabled the IPNs to simultaneously exhibit enantioselectivity and pH sensitivity in the glucose adsorption process. The reversibility of the boronic acid-derived ester structure facilitated the IPNs to be easily recycled, thus endowing the novel IPNs with diverse promising applications.
ObjectiveOur study aims to examine the associations of visceral adipose tissue (VAT) and epicardial adipose tissue (EAT) with subclinical cardiac dysfunction in a Chinese ...population.DesignCross-sectional.BackgroundEAT and VAT are the most important ectopic fat pools which were previously shown to be associated with subclinical cardiac dysfunction. However, few studies simultaneously measured both EAT thickness and VAT area, and explored their associations with cardiac dysfunction. Our study aims to examine the associations of VAT and EAT with subclinical cardiac dysfunction in a Chinese population.MethodsThe study subjects were recruited from Danyang County from 2018 to 2019. Using Philips CX50, we recorded EAT thickness at the end-systole in a long-axis view. The subclinical systolic and diastolic function were assessed by two-dimensional speckle tracking, and transmitral and tissue Doppler imaging, respectively. Using Omron HDS-2000, we measured VAT area by dual bioelectrical impedance analysis.ResultsThe 1558 participants (age, 52.3±12.8 years) included 930 (59.7%) women. Compared with women, men had higher VAT area (99.4 vs 70.1 cm2; p<0.0001) but lower EAT thickness (4.02 vs 4.46 mm; p<0.0001). In simple correlation analyses, EAT thickness and VAT area were positively associated with E/e’ ratio (r=0.16 to 0.20; all p<0.0001) and negatively with global longitudinal strain (GLS) and e’ (r=−0.12 to −0.37; all p<0.0001). Furthermore, VAT area was associated with left ventricular ejection fraction (LVEF) (r=−0.14; p<0.0001). After adjustment for confounding factors, the association of EAT with GLS and that of VAT with e’ and E/e’ ratio remained significant (all p≤0.001), whereas the associations of EAT with subclinical diastolic dysfunction and that of VAT with systolic function became non-significant (all p≥0.11). Analyses on further adjustment for LVEF showed similar results.ConclusionsIncreased EAT thickness was associated with worse subclinical systolic dysfunction, while greater VAT area was associated with early diastolic dysfunction.
This article reports the first optically active macroporous materials constructed by helical substituted polyacetylene and prepared by a high internal phase emulsion (HIPE) technique. The macroporous ...(∼3 μm) materials were fabricated simply through polymerization of the continuous phase in HIPEs. The porous structures of the resulting materials can be adjusted by varying the fraction of the dispersed phase. The obtained materials were characterized by regular pore morphology, high porosity, and low density. Circular dichroism and UV–vis absorption spectra demonstrated that the substituted polyacetylene forming the materials adopted chirally helical conformations, which endowed the materials with considerable optical activity. The optically active porous materials were used as chiral inducers and efficiently induced enantioselective crystallization of threonine and alanine racemates. l-Threonine and l-alanine were preferably induced to form crystals from the respective racemic solutions. The prepared materials open a new type of functional chiral materials with potential applications in asymmetric catalysis, chiral resolution, etc.
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IJS, KILJ, NUK, PNG, UL, UM
The association of cardio‐ankle vascular index (CAVI), with subclinical cardiac dysfunction in hypertensive patients is unclear. We aim to examine their relationship in hypertensive patients compared ...with that in normotensive subjects. Our study included 1887 subjects enrolled from Danyang between 2018 and 2019. CAVI was measured using VaSera VS‐1500A device. We performed conventional echocardiography to measure ejection fraction (EF) and E/A, tissue Doppler to measure mitral annular early diastolic velocities (e’), and speckle‐tracking to estimate left ventricular (LV) global longitudinal strain (GLS). LV mass index (76.3, 80.0, and 84.0 g/m2), and E/e’ (7.6, 8.2, and 8.8) were increased and GLS (21.1, 21.0, and 20.4%), E/A (1.2, 1.0, and 0.8) and e’ velocity (11.2, 9.4, and 8.2 cm/s) was decreased from tertiles 1–3 of CAVI on unadjusted analyses (P < .001). After adjustment for covariates, GLS, E/A, and e’ were still significantly decreased from tertiles 1–3 of CAVI (P ≤ .04). Further sensitive analyses revealed a similar association pattern for diastolic function but not systolic function. Compared with the lowest tertile, subjects with a top tertile of CAVI were at higher risk of subclinical LV systolic dysfunction in hypertensive patients (OR = 2.61; P = .005). Increased CAVI is associated with worse subclinical diastolic function. However, this relationship of CAVI to subclinical systolic function was more prominent in hypertensive patients.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Aims
The association of strictly defined metabolic healthy obese (MHO) with subclinical cardiac function was unclear. Our study aims to examine the role of MHO in subclinical cardiac dysfunction in a ...Chinese population.
Methods and results
The study subjects were recruited from Danyang from 2017 to 2019. Obesity was defined by body mass index (BMI) categories (normal weight, overweight and obesity). Metabolic health was strictly defined as having neither any of the guidelines recommended metabolic syndrome components nor insulin resistance. Thus, subjects were grouped by BMI categories and metabolic health status as six groups. Preclinical systolic (global longitudinal strain GLS) and diastolic function were assessed by 2D speckle tracking, and transmitral and tissue Doppler imaging, respectively. The 2757 participants (mean age ± standard deviation, 52.7 ± 11.7 years) included 1613 (58.5%) women, 999 (36.2%) obese, 2080 (75.4%) metabolically unhealthy and 93 (3.4%) MHO participants. After adjustment for covariates, the trend was similar for left ventricular (LV) ejection fraction (Ptrend ≥ 0.07) but significantly worse for GLS, e′ and E/e′ (Ptrend ≤ 0.02) across the six groups or passing from normal weight to obese individuals irrespective of metabolic status. MHO participants had lower GLS (20.4 vs. 21.4%) and e′ (9.6 vs. 10.6 cm/s) compared with controls (P < 0.0001) but had similar GLS (P = 0.47) compared with metabolically unhealthy obese (MUO). Regardless of obesity status, metabolically unhealthy participants had worse diastolic function compared with their metabolically healthy counterparts (P ≤ 0.0004). Compared with controls, MHO individuals were at higher risk of subclinical LV systolic dysfunction (OR = 3.44, 95% CI = 1.25–9.49, P = 0.02). These results were robust to sensitivity analysis.
Conclusions
MHO was substantially associated with worse subclinical systolic function although early diastolic dysfunction seemed to be more accentuated in MUO.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Objective. Type 2 diabetes (T2DM) is a global epidemic and increases mortality due to its vascular complications. Chemerin has been found to exert a major role in glucose and lipid metabolism. The ...aim of this study was to explore the correlation between plasma chemerin levels and microangiopathy in patients with T2DM. Methods. A total of 598 T2DM patients were classified into two groups: with and without microvascular complications. Anthropometric parameters and blood pressure were taken. The amounts of glycosylated hemoglobin, glucose, lipid profiles, creatinine, and chemerin concentrations in the blood were determined. The presence and severity of nephropathy, retinopathy, and neuropathy were also evaluated by specific tests. Results. Plasma levels of chemerin in diabetic subjects with microvascular complications were markedly elevated compared to those without. The number of microvascular complications increased with high plasma chemerin levels. Patients with high chemerin levels had an increased incidence of nephropathy and retinopathy. Furthermore, the chemerin plasma concentrations increased with the progression of diabetic nephropathy with highest values in macroalbuminuria groups. In contrast, no significant difference was observed in plasma chemerin levels between subjects with and without peripheral neuropathy. Pearson correlation analysis showed that plasma chemerin levels were positively related to duration of diabetes, serum creatinine, and 24-hour urine albumin excretion, even after multiple adjustments. Using logistic regression analysis, plasma chemerin concentrations were independently associated with the presence of nephropathy and retinopathy, not neuropathy. Conclusion. This study elucidated a positive correlation between increased chemerin levels and the development of some subtypes of diabetic microangiopathy.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
While obesity and fat intake have been associated with the risk and prognosis of epithelial ovarian cancer, the association between the lipid levels and epithelial ovarian cancer phenotype remains ...controversial. We conducted a retrospective study of 349 epithelial ovarian cancer patients who received treatment at Jiangsu Cancer Hospital, China between 2011 and 2017. We analyzed age at diagnosis, blood pressure, plasma glucose content, body mass index (BMI), lipid levels and clinical parameters. Severity of epithelial ovarian cancer was classified according to the International Federation of Gynecology and Obstetrics (FIGO) grading system. Univariate analysis of the clinical factors according to the severity of epithelial ovarian cancer was followed by logistic regression analysis to identify clinical factors significantly associated with epithelial ovarian cancer severity. Univariate analysis indicated that age, BMI, triglyceride (TG), and high density lipoproteins (HDL) differed significantly among different stages of epithelial ovarian cancer (P<0.05). In the logistic regression model, elevated TG (OR: 1.883; 95% CI= 1.207-2.937), and low HDL (OR: 0.497; 95% CI= 0.298-0.829) levels were significantly associated with the high severity epithelial ovarian cancer. Our data indicate that high TG and low HDL levels correlate with a high severity of epithelial ovarian cancer. These data provide important insight into the potential relationship between the lipid pathway and epithelial ovarian cancer phenotype and development.
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