268 research outputs found

    STRUCTURAL EFFECTS OF VERAPAMIL ON CELL MEMBRANES AND MOLECULAR MODELS

    Get PDF
    ABSTRACT Verapamil is one of the frequently prescribed calcium channel blockers used in the treatment of hypertension and angina pectoris . Results of evaluations of the therapy have led to reports of toxic effects. This study presents several evidences that verapamil affects human cells. Scanning electron microscopy observations of intact human erythrocytes indicated that they underwent morphological alterations as increasing verapamil concentrations starting from 5 μM changed their discoid normal shape, and finally to hemolysis. Fluorescence spectroscopy on isolated unsealed human erythrocyte membranes confirmed these outcomes. In fact, the assays showed that verapamil induced a significant increase of the anisotropy parameters and a moderate one of the generalized polarization, indicative of enhanced order at the acyl chain and polar head regions of the erythrocyte membrane lipid bilayer. X-ray diffraction experiments on dimyristoylphosphatidylcholine and dimyristoylphosphatidylethanolamine bilayers, classes of the major phospholipids present in both outer and inner sides of the erythrocyte membrane, respectively showed that verapamil perturbed the polar head and acyl chain regions of both lipid bilayers. These interactions were found to be stronger with DMPC bilayers. On the other hand, human SH-SY5Y neuroblastoma cells incubated with verapamil suffered a sharp decrease of cell viability

    Sistem pengendalian internal dalam upaya mencegah penyimpangan dana pembiayaan di KSPPS BMT Aulia Magelang

    Get PDF
    Pengendalian internal merupakan sistem dan prosedur yang digunakan perusahaan untuk mencapai sasaran dan tujuan yang diinginkan, yaitu menghasilkan laporan keuangan yang akurat serta mendorong ketaatan terhadap kebiajakn dan peraturan yang telah ditetapkan. sistem pengendalian mencegah penyimpangan dana pembiayaan pada KSPPS Amanah Usaha Mulia Magelang dapat diambil sebagai berikut : Sistem Pengendalian Internal KSPPS Amanah Usaha Mulia Magelang. Sistem pengendalian internal yang digunakan KSPPS Amanah Usaha Mulia Magelang dalam pencegah penyimpangan dana pembiayaan yaitu dengan melakukan pengecekan rutin untuk mencegah resiko yang tidak diinginkan. setiap pegawai dituntut untuk jujur dan bertanggungjawab dengan tugas dan wewenangnya masing-masing, dan paling penting semua pegawai saling berkerjasama untuk mencapai tujuan yang telah ditetapkan KSPPS Amanah Usaha Mulia Magelang. Efektivitas sistem pengendalian internal KSPPS Amanah Usaha Mulia Magelang. Keefektivitasan sistem pengendalian internal KSPPS Amanah Usaha Mulia Magelang sudah berjalan sesuai dengan perencanaan yang telah dituju, dalam pengoperasiannya juga sudah sesuai dengan prinsip dan komponen di pengendalian internal. Prinsip dan komponen tersebut antara lain : pegawai yang berkualitas dan dapat dipercaya, pemisahan wewennag, pengawasan, penetapan tanggungjawab secara perseorangan, pencatatan yang seksama dengan segera, penjagaan fisik, pemisaan oleh petugas yang bebas dari tugas rutin merupakan prinsip pengendalian internal dan komponen pengendalian meliputi lingkungan pengendalian, penentuan risiko manajemen, aktivitas pengendalian, informasi dan komunikasi dan pemantauan

    MICROALGAE BIOPOLYMERS: A REVIEW

    Get PDF
    Algae are ubiquitous organisms whose capabilities have drawn much attention as of late in the bioengineering field due to their potential to enable a wide range of bioproducts. Microalgae are ideal organisms for the application of the biorefinery concept since they can be grown in wastewater and, at the same time, produce many products of commercial interest. These microorganisms are also known for their resilience to extreme environmental conditions and suitable cell growth rates. Beyond the known potential for biofuel production, these microorganisms can still produce other compounds, being lipids, pigments, vitamins, proteins, and polysaccharides, whose applications go from pharmaceutical to agricultural industries. Recently, the research focus has been directed to the biopolymer-producing ability of both micro- and macroalgae, as they can be rather varied and useful to many applications. However, this is still an ongoing research field, and new data are frequently added in the literature, notably on biomass processing, which can be done with the intent of use into dyes, bioplastics, paints, and even as biochar in solid fuel cells. Microalgae-based biopolymers can be used in a wide range of products, nevertheless, the resulting process efficiency and yields depend on the extraction process utilized, as well as on the microalgae species used and the culture conditions. Furthermore, the polymer extraction can be done directly with common solvents at atmospheric pressure or with other fluids, such as supercritical CO2 or subcritical solvents, and assisted by specific treatments, e.g., ultrasound and microwave. The residual biomass can still be used to produce other less valuable products, such as feedstock, and energy via combustion. In this sense, the present work aims to provide a state-of-the-art review on microalgae biopolymers. Issues related to the efficiency of current treatment methods, industrial applications, and environmental performance are presented and discussed. Besides, the perspectives in this area of knowledge are also a contribution of the present work, the extent to which scientific research is still under development

    Experimental aluminum pathology in rabbits: effects of hydrophilic and lipophilic compounds.

    Get PDF
    Aluminum lactate [Al(lact)3] (hydrophilic, hydrolytically unstable) and aluminum acetylacetonate [Al(acae)3] (lipophilic, hydrolytically stable) were tested as potential toxicants to rabbits upon IV administration both as aqueous solutions and as liposome suspensions. Both chemicals behaved as cardiotoxic agents when administered as aqueous solutions, but Al(acae)3 was at least two orders of magnitude more active than Al(lact)3. Al(acae)3, but not Al(lact)3, caused myocardial infarcts resembling those in humans (with contraction bands) at doses as low as 0.24 mg/kg body weight, as well as a prominent acanthocytosis. Al(lact)3, when administered as a liposome suspension, was about 300 times more toxic than in aqueous solution, although cardiac damage was not infarctual in character. Both chemical and physical speciation of aluminum(III) thus play an essential role in determining the toxicity of the metal

    Improving outcomes for hospital patients with critical bleeding requiring massive transfusion: The Australian and New Zealand Massive Transfusion Registry study methodology

    Get PDF
    Background: The Australian and New Zealand (ANZ) Massive Transfusion (MT) Registry (MTR) has been established to improve the quality of care of patients with critical bleeding (CB) requiring MT (≥ 5 units red blood cells (RBC) over 4 h). The MTR is providing data to: (1) improve the evidence base for transfusion practice by systematically collecting data on transfusion practice and clinical outcomes; (2) monitor variations in practice and provide an opportunity for benchmarking, and feedback on practice/blood product use; (3) inform blood supply planning, inventory management and development of future clinical trials; and (4) measure and enhance translation of evidence into policy and patient blood management guidelines. The MTR commenced in 2011. At each participating site, all eligible patients aged ≥18 years with CB from any clinical context receiving MT are included using a waived consent model. Patient information and clinical coding, transfusion history, and laboratory test results are extracted for each patient’s hospital admission at the episode level. Results: Thirty-two hospitals have enrolled and 3566 MT patients have been identified across Australia and New Zealand between 2011 and 2015. The majority of CB contexts are surgical, followed by trauma and gastrointestinal haemorrhage. Validation studies have verified that the definition of MT used in the registry correctly identifies 94 % of CB events, and that the median time of transfusion for the majority of fresh products is the ‘product event issue time’ from the hospital blood bank plus 20 min. Data linkage between the MTR and mortality databases in Australia and New Zealand will allow comparisons of risk-adjusted mortality estimates across different bleeding contexts, and between countries. Data extracts will be examined to determine if there are differences in patient outcomes according to transfusion practice. The ratios of blood components (e.g. FFP:RBC) used in different types of critical bleeding will also be investigated. Conclusions: The MTR is generating data with the potential to have an impact on management and policy decision-making in CB and MT and provide benchmarking and monitoring tools for immediate application

    Resveratrol Acts Not through Anti-Aggregative Pathways but Mainly via Its Scavenging Properties against Aβ and Aβ-Metal Complexes Toxicity

    Get PDF
    It has been recently suggested that resveratrol can be effective in slowing down Alzheimer's disease (AD) development. As reported in many biochemical studies, resveratrol seems to exert its neuro-protective role through inhibition of β-amyloid aggregation (Aβ), by scavenging oxidants and exerting anti-inflammatory activities. In this paper, we demonstrate that resveratrol is cytoprotective in human neuroblastoma cells exposed to Aβ and or to Aβ-metal complex. Our findings suggest that resveratrol acts not through anti-aggregative pathways but mainly via its scavenging properties
    • …
    corecore