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Certain Compounds (certain + compound)
Selected AbstractsImbalance of plasma membrane ion leak and pump relationship as a new aetiological basis of certain disease statesJOURNAL OF INTERNAL MEDICINE, Issue 6 2003G. Ronquist Abstract. The basis for life is the ability of the cell to maintain ion gradients across biological membranes. Such gradients are created by specific membrane-bound ion pumps [adenosine triphosphatases (ATPases)]. According to physicochemical rules passive forces equilibrate (dissipate) ion gradients. The cholesterol/phospholipid ratio of the membrane and the degree of saturation of phospholipid fatty acids are important factors for membrane molecular order and herewith a determinant of the degree of non-specific membrane leakiness. Other operative principles, i.e. specific ion channels can be opened and closed according to mechanisms that are specific to the cell. Certain compounds called ionophores can be integrated in the plasma membrane and permit specific inorganic ions to pass. Irrespective of which mechanism ions leak across the plasma membrane the homeostasis may be kept by increasing ion pumping (ATPase activity) in an attempt to restore the physiological ion gradient. The energy source for this work seems to be glycolytically derived ATP formation. Thus an increase in ion pumping is reflected by increased ATP hydrolysis and rate of glycolysis. This can be measured as an accumulation of breakdown products of ATP and end-products of anaerobic glycolysis (lactate). In certain disease entities, the balance between ATP formation and ion pumping may be disordered resulting in a decrease in inter alia (i.a.) cellular energy charge, and an increase in lactate formation and catabolites of adenylates. Cardiac syndrome X is proposed to be due to an excessive leakage of potassium ions, leading to electrocardiographic (ECG) changes, abnormal Tl-scintigraphy of the heart and anginal pain (induced by adenosine). Cocksackie B3 infections, a common agent in myocarditis might also induce an ionophore-like effect. Moreover, Alzheimer's disease is characterized by the formation of extracellular amyloid deposits in the brain of patients. Perturbation of cellular membranes by the amyloid peptide during the development of Alzheimer's disease is one of several mechanisms proposed to account for the toxicity of this peptide on neuronal membranes. We have studied the effects of the peptide and fragments thereof on 45Ca2+ -uptake in human erythrocytes and the energetic consequences. Treatment of erythrocytes with the ,1,40 peptide, results in qualitatively similar nucleotide pattern and decrease of energy charge as the treatment with Ca2+ -ionophore A23187. Finally, in recent studies we have revealed and published in this journal that a rare condition, Tarui's disease or glycogenosis type VII, primarily associated with a defect M-subunit of phosphofructokinase, demonstrates as a cophenomenon an increased leak of Ca2+ into erythrocytes. [source] Synthesis and Antistaphylococcal Activity of N -Substituted-1H -benzimidazole-sulphonamidesARCHIV DER PHARMAZIE, Issue 1 2010M. Orhan Püsküllü Abstract A series of N -substituted-1H -benzimidazole-5(6)-sulfonamides and 3-(5,6-dichloro-1H -benzimidazol-2-yl)- N -substituted benzensulfonamides were synthesized and evaluated for antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). Certain compounds inhibit bacterial growth with low MIC (,g/mL) values. The most active compounds 30, 31, and 32 have the lowest MIC values with 0.39 to 0.19 ,g/mL. Among the compounds having sulfonamido moities, 16, 23, and 24 exhibited the strongest antibacterial activity with 1.56 ,g/mL MIC values. [source] Cryopreservation of fish sperm: applications and perspectivesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010E. Cabrita Summary Cryopreservation is of interest not only for fish farming but also for the conservation and genetic improvement of resources. This technique has been well established in some freshwater fish species mainly, salmonid, sturgeons and carps, however, only in the last decade research was focused in marine fish species. The benefits of sperm cryopreservation include: (i) synchronization of gamete availability of both sexes, (ii) sperm economy; (iii) simplification of broodstock management, (iv) transport of gametes from different fish farms, and (v) germplasm storage for genetic selection programs or conservation of species. These issues would certainly benefit the aquaculture industry. The tremendous impact that biotechnology is having in aquaculture has been particularly obvious in recent years. Several species are being used as research models not only for aquaculture development applications but also for medical research. Sperm cryopreservation can give an important contribution in the germ storage of all transgenic lines. However, in all applications in fish sperm, cryopreservation needs to overcome a lack in standardization of methodologies and procedures, a correct assay of seminal quality and the development of tools to characterize cryoinjury. Many efforts have recently been made in the study of DNA using different approaches such as the comet assay (single cell gel electrophoresis), TUNEL (terminal deoxynucleotidyl transferase-nick-end-labelling), SCSA (sperm chromatin structure assay) and the analysis of specific DNA sequences using RT-PCR, since DNA damage may impair fertility or embryo development. Cryopreservation of gametes would certainly benefit from a higher concern on male improvement, basically through nutrition or selection of resistant stocks (e.g. stress resistant individuals or highly adapted to captivity) producing gametes of higher quality. There is a huge window of opportunities for improve the resistance of cells to cryopreservation through diet supplementation of certain compounds such as amino acids (taurine and hypotaurine), vitamins (Vit. E and C) and lipids or through a direct supplementation of the extender media. An equilibrium of those compounds will improve spermatozoa and seminal plasma composition protecting cells against oxidative stress (lipid peroxidation, protein oxidation, DNA fragmentation, enzyme protection) that is gaining each day more importance in cryodamage research. [source] Phytotherapeutics: an evaluation of the potential of 1000 plantsJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 1 2010G. Cravotto MD Summary Objective:, The aim of this review is to evaluate and summarize the available scientific information on the commonest plant extracts marketed in Western countries. In view of the intense, ongoing search for new plant extracts with powerful anti-inflammatory activity, we paid particular attention to this topic. The aim is to provide broad coverage of as many potentially useful plants as possible and then to focus on those with the greatest therapeutic potential. Methods:, Our bibliographic sources were the SciFinder databases: CAPLUS, MEDLINE, REGISTRY, CASREACT, CHEMLIST, CHEMCATS (update to October 2007). In order to assess the value of clinical trials, we focused a specific search on clinical investigations concerning nine plants with the most trial data, viz., Althaea officinalis, Calendula officinalis, Centella asiatica, Echinacea purpurea, Passiflora incarnata, Punica granatum, Vaccinium macrocarpon, Vaccinium myrtillus, Valeriana officinalis. This was carried out in several databases (update to June 2008): ISI Web of KnowledgeSM (ISI WoK), SciFinder (CAPLUS, MEDLINE, REGISTRY, CASREACT, CHEMLIST, CHEMCATS) and PubMed (indexed for MEDLINE). Results:, Our survey covers roughly a 1000 plants, although clinical trials have been published only for 156 plants supporting specific pharmacological activities and therapeutic applications. However, for about half of the plants, in vitro and in vivo studies provide some support for therapeutic use. For one-fifth of the plants included in our search, only phytochemical studies were found. Their properties and indications were often attributed to the presence of certain compounds, but no evidence concerning the activities of the whole extracts was presented. We found that for about 12% of the plants, currently available on the Western market, no substantial studies on their properties had been published, while there was strong evidence that 1 in 200 were toxic or allergenic, so that their use ought to be discouraged or forbidden. Nine plants had considerable evidence of therapeutic effect, viz., A. officinalis, Calendula officinalis, Centella asiatica, E. purpurea, Passiflora incarnata, Punica granatum, Vaccinium macrocarpon, Vaccinium myrtillus, Valeriana officinalis. Conclusion:, The present review provides a baseline on the level of evidence available on many herbal preparations and should be of help to those intending to research further on these topics. [source] Management of complications after implantation of fillersJOURNAL OF COSMETIC DERMATOLOGY, Issue 1 2004Koenraad De Boulle Summary Soft tissue augmentation is widely practised by a variety of different practitioners. A new classification of filler substances and procedures, taking into account long-term safety and reversibility of side effects, is proposed: i non-permanent and biodegradable, ii,semi-permanent and biodegradable, iii,permanent and reversible, iv,permanent and non-reversible. Complications and adverse effects occur with all fillers and all filler procedures. Insufficient experience is an important contributory factor. Underreporting is probably common. Commonest are haematomas, ecchymoses, infections, papulopustular or acneiform lesions, non-hypersensitivity related swelling and oedema, erythema, changes in pigmentation, palpability of the implant and necrosis of overlying tissue. Specific therapeutic approaches for these complications and practical recommendations to minimize or avoid them are discussed. Hypersensitivity reactions and granuloma formation are the most distressing adverse effects. They can occur with most fillers. Mostly these hypersensitivity reactions are local granulomas but, rarely, generalized reactions also occur. Case reports of systemic reactions after injection of hyaluronic acid are documented. Treatments include steroids, minocycline and immunomodulatory agents, such as cyclosporin, tacrolimus and ascomycin. In selected cases, surgical procedures are necessary to elimirate granulomatous reactions. Implant migration and facial lipoatrophy are encountered with certain compounds. Extreme caution is therefore advocated before using permanent and non-reversible products for soft tissue augmentation. Those who use fillers need to be familiar with the complications of fillers and with the treatment of those complications. [source] GC-MS analysis of multiply derivatized opioids in urineJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2007Bud-Gen Chen Abstract Opiates such as hydrocodone, hydromorphone, oxycodone, noroxycodone, and oxymorphone reportedly may interfere with the analysis of morphine and codeine. The analysis of these compounds themselves also is an important issue. Thus, double derivatization approaches utilizing methoxyamine and hydroxylamine to first form oxime products with keto-opiates, followed by the derivatization with trimethylsilyl (TMS) or propionyl groups, have been developed for the simultaneous analysis of these compounds. However, these studies have not included all compounds of interest and resulted in inadequate chromatographic resolution or significant intensity cross-contribution between the ions designating the analyte and its deuterated internal standard for certain compounds. By exploring three-step derivatization approaches with the combination of various derivatization groups and orders, this study concluded that application of methoxyimino/propionyl/TMS groups, in the order listed, facilitated the simultaneous analysis of eight opiates (morphine, 6-acetylmorphine, hydromorphone, oxymorphone, codeine, hydrocodone, oxycodone and noroxycodone) in urine samples, achieving satisfactory limits of quantitation and detection. In addition, the adapted approach resulted in two usable products for morphine and codeine providing alternatives, should interferences render any of these products non-usable. Copyright © 2007 John Wiley & Sons, Ltd. [source] Determination of phenol using an enhanced chemiluminescent assayLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 1 2003A. D. Ilyina Abstract Enhanced chemiluminescence (ECL) describes the phenomenon of increased light output in the luminol oxidation reaction catalysed by horseradish peroxidase (HRP) in the presence of certain compounds, such as para -iodophenol. In this work, the effects of phenol on the para -iodophenol-enhanced HRP-catalysed chemiluninescent reaction intensity in an aqueous buffer (Tris,HCl buffer, pH 8.5) and in a surfactant,water,octane mixture were compared. Preincubation of HRP at low phenol concentrations stimulated the chemiluminescent intensity in the assay performed in an aqueous buffer, but did not have significant effect in the sodium bis(2-ethylhexyl)sulphosuccinate) (Aerosol OT, AOT) applied system. It was also observed that HRP preincubation with phenol concentration higher than 0.003,mg/mL produced an inhibitory effect on the enzyme activity for both assay systems. Only an inhibitory effect of phenol on the chemiluminescent intensity in the surfactant system in octane (as organic solvent) was observed. Three assays were developed to determine phenol concentration in water and in an organic solvent mixture. The detection limits were 0.006, 0.003 and 0.0005,mg/mL, respectively, for the buffer-containing system, the AOT-applied system with phenol standard solutions in water and for the AOT-applied system with phenol standard solutions in octane. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||