220 research outputs found
Toxic compounds in honey
No full textThere is a wealth of information about the nutritional and medicinal properties of honey. However, honey may contain compounds that may lead to toxicity. A compound not naturally present in honey, named 5‐hydroxymethylfurfural (HMF), may be formed during the heating or preservation processes of honey. HMF has gained much interest, as it is commonly detected in honey samples, especially samples that have been stored for a long time. HMF is a compound that may be mutagenic, carcinogenic and cytotoxic. It has also been reported that honey can be contaminated with heavy metals such as lead, arsenic, mercury and cadmium. Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. In addition, Melicope ternata and Coriaria arborea from New Zealand produce toxic honey that can be fatal. There are reports that honey is not safe to be consumed when it is collected from Datura plants (from Mexico and Hungary), belladonna flowers and Hyoscamus niger plants (from Hungary), Serjania lethalis (from Brazil), Gelsemium sempervirens (from the American Southwest), Kalmia latifolia, Tripetalia paniculata and Ledum palustre. Although the symptoms of poisoning due to honey consumption may differ depending on the source of toxins, most common symptoms generally include dizziness, nausea, vomiting, convulsions, headache, palpitations or even death. It has been suggested that honey should not be considered a completely safe food. Copyright © 2013 John Wiley & Sons, Ltd
Physicochemical and Antioxidant Properties of Algerian Honey
No full textThe aim of the present study was to characterize the physical, biochemical and antioxidant properties of Algerian honey samples (n = 4). Physical parameters, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content were measured. Several biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. The mean pH was 3.84 ± 0.01, and moisture the content was 13.21 ± 0.16%. The mean EC was 0.636 ± 0.001, and the mean TDS was 316.92 ± 0.92. The mean color was 120.58 ± 0.64 mm Pfund, and the mean 5-hydroxymethylfurfural (HMF) content was 21.49 mg/kg. The mean total sugar and reducing sugar contents were 67.03 ± 0.68 g/mL and 64.72 ± 0.52 g/g, respectively. The mean sucrose content was 2.29 ± 0.65%. High mean values of phenolic (459.83 ± 1.92 mg gallic acid/kg), flavonoid (54.23 ± 0.62 mg catechin/kg), ascorbic acid (159.70 ± 0.78 mg/kg), AEAC (278.15 ± 4.34 mg/kg), protein (3381.83 ± 6.19 mg/kg) and proline (2131.47 ± 0.90) contents, as well as DPPH (39.57% ± 4.18) and FRAP activities [337.77 ± 1.01 µM Fe (II)/100 g], were also detected, indicating that Algerian honey has a high antioxidant potential. Strong positive correlations were found between flavonoid, proline and ascorbic acid contents and color intensity with DPPH and FRAP values. Thus, the present study revealed that Algerian honey is a good source of antioxidants
A 15-year single centre retrospective study of antiphospholipid syndrome patients from Northern Malaysia
No full text78.6%) followed by recurrent venous thrombosis (10/1758.8%). For other clinical features, menorrhagia was the most frequently observed manifestation (4/1428.6%) followed by aPLs-associated thrombocytopenia (4/1723.5%) and ovarian cyst (3/1
Physicochemical and antioxidant properties of Bangladeshi honeys stored for more than one year
No full textBackgroundThere is no available information on physicochemical and antioxidant properties on Bangladeshi honey. We investigated five different monofloral and three different multifloral honey samples collected from different parts of Bangladesh.MethodsThe levels of phenolics, flavonoids, ascorbic acid, ascorbic acid equivalent antioxidant content (AEAC), proline, protein and antioxidants were determined in the honey samples using ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays.ResultsThe highest level of phenolic was 688.5 ± 5.9 mg Gallic acid/kg, and the highest level of flavonoid was 155 ± 6.9 mg Catechin/kg. The highest color intensity was 2034.00 ± 17.5 mAU, and the highest protein content was 8.6 ± 0.0mg/g. High levels of proline (2932.8 ± 3.7 mg/kg), ascorbic acid (154.3 ± 0.3 mg/kg), AEAC (34.1 ± 1.4mg/100 g) and FRAP (772.4 ± 2.5 μmol Fe (II)/100 g) were detected in some of the samples, especially the multifloral honey samples, indicating good antioxidant properties. A strong positive correlation was found between phenolics, flavonoids, DPPH, FRAP and color intensity, indicating that in addition to total phenolic and flavonoid concentrations, color intensity and amino acid are good indicators of the antioxidant potential of honey. Except for a single sample (BDH-6), the honey samples stored for 1.5 years at room temperature still had 5-hydroxymethylfurfural (HMF) values within the recommended range (mean = 10.93 mg/kg), indicating that the rate of HMF production in Bangladeshi honey samples is low.ConclusionIt is postulated that the low rate of HMF formation could be attributed to the acidic and low moisture content in the samples. In general, multifloral honeys have higher antioxidant properties based on their high levels of phenolics, flavonoids, AEAC, DPPH and FRAP when compared to monofloral honeys. We also found that monofloral honey samples from Guizotia abyssinica and Nigella sativa had high antioxidant properties
Investigating the Decision-Making Process of Physicians in Rural Ontario: The Perspectives and Attitudes on Medical Cannabis
No full textThis thesis will guide health communities to better understand the clinical decision-making process that physicians from rural Ontario undergo when considering whether to prescribe medical cannabis to patients for their medical condition. Very few studies have been conducted which examine the perspectives of physicians on medical cannabis, especially in rural areas, and these studies have found that most physicians are skeptical towards medical cannabis. This skeptical perspective of physicians has complicated the clinical decision-making process as “recent changes in media reports and changing trends in social media propose a change in the attitudes towards cannabis (Zolotov et al., 2018, p.5).” Physicians practicing in rural Ontario are currently being recruited to participate in semi-structured interviews to explore the issues which they prioritize the most. Once completed, the findings from this study will identify common themes and trends that could help influence change in physician practice and healthcare policy
An Implicit Hybrid Turbulence Model for Wall-Bounded Turbulent Aerodynamics
No full textResolving the small-scale streaks in viscous boundary layers require excessively refined, isotropic grids beyond the capability of all but the most powerful supercomputing facilities. This thesis contributes to the widespread effort in developing hybrid turbulence closures, which aim to reduce near-wall resolution requirements yet maintain turbulence-resolving capability in free-shear flow regions. This thesis evaluated the performance of an Implicit Large-Eddy Simulation (ILES) approach implemented within a very high-order accurate framework for a structured finite-volume, compressible solver. A new hybrid RANS-ILES model was proposed and systematically developed using hybrid length-scale modifications, a blending function, a boundary layer detection variable and a smoothing function. Different formulations for each of these mechanisms were numerically assessed, classified and eliminated to form the most optimal algorithm. This avoids some limitations of eddy-viscosity based subgrid-scale models used in conventional Large-Eddy Simulation and reduces case-specific calibration. The RANS-ILES hybrid model was used to simulate turbulent boundary layers highlighting its robust performance even on grids designed to induce Modelled-Stress Depletion. Under-resolved ILES results were degraded compared to URANS for such grids. Two Reynolds number regimes were used for flow around a cylinder and force coefficients, separation angles, wake profiles and shedding frequencies agreed well with past hybrid models, LES and experiments. The auxiliary transport equation successfully identified turbulent and non-turbulent regions in two automotive test cases. Surface pressures agreed well with experiments and a commercial LBM solver, despite some modelling simplifications. These simulations also leveraged high-order numerics and accurately predicted dominant spectral modes and coherent structures
MicroRNA (miRNA): A New Dimension in the Pathogenesis of Antiphospholipid Syndrome (APS)
No full textMicroRNAs (miRNAs) are single-stranded, endogenous RNA molecules that play a significant role in the regulation of gene expression as well as cell development, differentiation, and function. Recent data suggest that these small molecules are responsible for the regulation of immune responses. Therefore, they may act as potent modulators of the immune system and play an important role in the development of several autoimmune diseases. Antiphospholipid syndrome (APS) is an autoimmune systemic disease characterized by venous and/or arterial thromboses and/or recurrent fetal losses in the presence of antiphospholipid antibodies (aPLs). Several lines of evidence suggest that like other autoimmune disorders, miRNAs are deeply involved in the pathogenesis of APS, interacting with the function of innate and adaptive immune responses. In this review, we characterize miRNAs in the light of having a functional role in the immune system and autoimmune responses focusing on APS. In addition, we also discuss miRNAs as potential biomarkers and target molecules in treating APS
Antiphospholipid antibodies and antiphospholipid syndrome in cancer: Uninvited guests in troubled times
No full textAntiphospholipid antibodies (aPLs) are autoantibodies with laboratory significance in developing thrombosis and pregnancy morbidity in antiphospholipid syndrome (APS). High prevalence of aPLs namely - anticardiolipin, anti-β2-glycoprotein I, lupus anticoagulant, antiphosphatidylcholine, antiphosphatidylserine, antiphosphatidylinositol, antiphosphatidylethanolamine and antiprothrombin antibodies have been observed in patients with different types of haematological malignancies and solid tumours. Although cancer patients have high risk of developing thrombosis, the risk becomes even higher in aPLs carriers. Although the relationship between aPLs and cancer has to be further investigated, however, the presence of aPLs in neoplastic patients can possibly increase the risk of developing thrombosis. As the pathogenic role of aPLs in cancer is still a matter of debate, more researches should be conducted on the association between the aPLs and malignancies towards the potential impact on understanding the pathogenicity and treatment when cancer and APS coexists.</p
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