305 research outputs found
The role of macrophage phenotypes in atherosclerosis
Background and aim: The rupture of atherosclerotic plaque is the key underlying cause of cardiovascular episodes including heart attack and stroke. A key contributor to plaque instability is the macrophage. We found that while M1 macrophages are associated with plaque instability, M2 macrophages are not; rather they produce matrix molecules such as collagen that provide structural integrity to the cap. Modulating the balance of macrophage phenotypes in the plaques may hence be a treatment option. However, since some matrices, particularly the proteoglycans, can retain lipoproteins in the arterial wall, this study examined what proteoglycans M1 and M2 macrophages produce, and how is their degree of lipid binding. Method: Human monocyte-like THP-1 cells or the monocytes isolated from healthy donors were differentiated into M1 and M2 macrophages (and foam cells). The structure and low-density lipoprotein (LDL) binding ability of the proteoglycans were assessed. Results: M1 and M2 macrophages secreted a range of proteoglycans such as biglycan, perlecan and versican, with M2 macrophages producing more perlecan and versican. The glycosaminoglycan (GAG) chains decorating the core protein of these proteoglycans included chondroitin sulphate and heparan sulphate. The chondroitin sulphate produced by M1 macrophages were more sulphated than M2. Heparan sulphate from both cells included non-sulphated and sulphated disaccharides, with the latter being more abundant in the M1. The M1 proteoglycans bound more LDL than those of M2 and this was mediated by heparan sulphate. In contrast, LDL binding sites were found on the M2 proteoglycan core proteins, such as perlecan, with increased LDL binding evident upon cleavage of GAGs. M2 macrophages were co-localised with perlecan and lipid accumulation in plaques, suggesting that they may help in LDL retention via perlecan. When M1 and M2 macrophages transformed into foam cells, they produced less proteoglycans. However, the proteoglycans did not differ in the degree of LDL binding between the phenotypes. Conclusion: Both M1 and M2 macrophages produced proteoglycans that could bind LDL, but in different ways: the M1 macrophage-derived proteoglycans bound LDL via heparan sulphate, whereas those produced by M2 macrophages used core proteins to bind LDL. Therefore, M1 and M2 macrophages are likely to contribute to LDL retention during the development of atherosclerosis
Association between Hypertension and Periodontitis: Possible Mechanisms
This review is to examine the current literatures on the relationship between periodontitis and hypertension as well as to explore the possible biological pathways underlying the linkage between these health conditions. Hypertension is one of the major risk factors for cardiovascular diseases. Oxidative stress and endothelial dysfunction are among the critical components in the development of hypertension. Inflammation has received much attention recently and may contribute to a pivotal role in hypertension. Periodontitis, a chronic low-grade inflammation of gingival tissue, has been linked to endothelial dysfunction, with blood pressure elevation and increased mortality risk in hypertensive patients. Inflammatory biomarkers are increased in hypertensive patients with periodontitis. Over the years, various researches have been performed to evaluate the involvement of periodontitis in the initiation and progression of hypertension. Many cross-sectional studies documented an association between hypertension and periodontitis. However, more well-designed prospective population trials need to be carried out to ascertain the role of periodontitis in hypertension
Na4Ir3O8 as a 3D spin liquid with fermionic spinons
Spin liquid states for spin-1/2 antiferromagnetic Heisenberg model on a
hyperkagome lattice are studied. We classify and study flux states according to
symmetries. Applying this model to Na4Ir3O8, we propose that the high
temperature state may be described by a spinon Fermi surface, which forms a
paired state with line nodes below 20 K. The possible mixed spin singlet and
spin triplet pairing states are discussed according to the lattice symmetry
which breaks inversion.Comment: final versio
Heated vegetable oils and cardiovascular disease risk factors
Cardiovascular disease (CVD) is one of the leading major causes of morbidity and mortality worldwide. It may result from the interactions between multiple genetic and environmental factors including sedentary lifestyle and dietary habits. The quality of dietary oils and fats has been widely recognised to be inextricably linked to the pathogenesis of CVD. Vegetable oil is one of the essential dietary components in daily food consumption. However, the benefits of vegetable oil can be deteriorated by repeated heating that leads to lipid oxidation. The practice of using repeatedly heated cooking oil is not uncommon as it will reduce the cost of food preparation. Thermal oxidation yields new functional groups which may be potentially hazardous to cardiovascular health. Prolonged consumption of the repeatedly heated oil has been shown to increase blood pressure and total cholesterol, cause vascular inflammation as well as vascular changes which predispose to atherosclerosis. The harmful effect of heated oils is attributed to products generated from lipid oxidation during heating process. In view of the potential hazard of oxidation products, therefore this review article will provide an insight and awareness to the general public on the consumption of repeatedly heated oils which is detrimental to health
Duration of untreated bipolar disorder: A multicenter study
Little is known about the demographic and clinical differences between short and long duration of untreated bipolar disorder (DUB) in Chinese patients. This study examined the demographic and clinical features of short (≤2 years) and long DUB (\u3e2 years) in China. A consecutively recruited sample of 555 patients with bipolar disorder (BD) was examined in 7 psychiatric hospitals and general hospital psychiatric units across China. Patients’ demographic and clinical characteristics were collected using a standardized protocol and data collection procedure. The mean DUB was 3.2 ± 6.0 years; long DUB accounted for 31.0% of the sample. Multivariate analyses revealed that longer duration of illness, diagnosis of BD type II, and earlier misdiagnosis of BD for major depressive disorder or schizophrenia were independently associated with long DUB. The mean DUB in Chinese BD patients was shorter than the reported figures from Western countries. The long-term impact of DUB on the outcome of BD is warranted
Poultry Drinking Water Used for Avian Influenza Surveillance
Samples of drinking water from poultry cages, which can be collected conveniently and noninvasively, provide higher rates of influenza (H9N2) virus isolation than do samples of fecal droppings. Studies to confirm the usefulness of poultry drinking water for detecting influenza (H5N1) should be conducted in disease-endemic areas
The association between post-stroke depression, aphasia, and physical independence in stroke patients at 3-month follow-up
Objective: Few studies have examined the association between post-stroke depression (PSD), aphasia, and physical independence in Chinese patients. This study investigated the above association in stroke patients in China at 3-month follow-up.
Methods: Altogether 270 patients within 14 days after ischemic stroke were recruited and followed up at 3 months. PSD, aphasia, and physical functional status were measured using the Stroke Aphasia Depression Questionnaire (SADQ), Western Aphasia Battery (WAB), and modified Rankin Scale (mRS), respectively. Patients with mRS total score \u3e2 were considered as having “physical dependence.”
Results: Out of 248 patients at 3-month follow up, 119 (48%) were rated as having physical dependence. Multiple logistic regression analyses revealed that female (p = 0.04; OR = 2.2; 95% CI: 1.0–5.1), more severe stroke at admission (p \u3c 0.01; OR = 1.4; 95% CI: 1.3–1.5), and more severe PSD at 3 months (p = 0.01; OR = 1.05; 95% CI: 1.01–1.1) were independently associated with physical dependence at 3 months.
Conclusions: Greater PSD and stroke severity were independently associated with physical dependence at 3months after stroke. Aphasia was also associated with physical dependence but the relationship was not significant. Early and effective depression screening, treatment and stroke rehabilitation appear to be important to improve the physical outcome and reduce the burden of stroke survivors
Electrochemical Determination of Some Triphenylmethane Dyes by Means of Voltammetry
AbstractThis paper provides the investigation of electrochemical properties of triphenylmethane dyes using a voltammetric method with constant-current potential sweep. Malachite green (MG) and basic fuchsin (BF) have been chosen as representatives of the triphenylmethane dyes. The electrochemical behavior of MG and BF on the surface of a mercury-film electrode depending on рН, the nature of background electrolyte and scan rate of potential sweep have been investigated. The conditions of registration have been determined for MG and BF detecting in the solution. It is demonstrated that the reduction peak currents of MG and BF increase linearly with their concentration in the range of 9.0·10-5- 7.0·10-3 mol/dm3 for MG, 6.0·10-5 – 8.0 10-3 mol/dm3 for BF with correlation coefficients of 0.9987 and 0.9961, respectively. The detection limit of MG is 5.0·10-5 mol/dm3 and for BF - 2.0·10-5 mol/dm3
Applying a Comprehensive Action Determination Model to Examine the Recycling Behavior of Taipei City Residents
With the occurrence of rapid global economic growth concerns about waste and its related effects on the environment are on the rise. There has been an increasing focus towards sustainable development and waste recycling as part of environmental sustainability strategies, and the encouraging of recycling behavior has received considerable attention from various environmental stakeholders. While numerous studies have used grounded theories such as the theory of planned behaviors and the norm activation model to examine environmental behaviors, a lack of consideration of other important variables in these studies has been revealed. This study aimed to address this gap by adopting the comprehensive action determination model, which comprises a wider group of influencing variables related to norms, intentions, situations, and habits. This model was tested using structural equation modelling with a sample of 386 valid questionnaires collected from Taipei City residents in the domain of recycling behaviors. Results indicated that awareness had a positive influence on personal norms towards recycling behaviors; social norms had a positive influence on personal norms towards recycling behaviors; attitudes had a positive influence on recycling intentions; social norms had a positive influence on recycling intentions; personal norms had a positive influence on recycling intentions; perceived behavior control had a positive influence on recycling intentions; recycling intentions had a positive influence on recycling behavior; and recycling habits had a positive influence on recycling behavior. However, findings did not support the positive impact of perceived behavioral control on recycling behavior
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