RESUMEN
Interaction of doxorubicin hydrochloride (DOX) (anti-cancer drug) with hydro-compacted nanosilica A-300 (cA-300) alone or cA-300/human serum albumin (HSA) at a small content of water (hâ¯=â¯0.4â¯g per gram of dry silica) in different dispersion media (air, chloroform, and chloroform/trifluoroacetic acid) was analyzed using low-temperature 1H NMR spectroscopy, NMR cryoporometry and quantum chemistry to elucidate specific changes in the interfacial layers. Initial (bulk density ρbâ¯≈â¯0.046â¯g/cm3) and hydro-compacted (ρbâ¯≈â¯0.051-0.265â¯g/cm3 as a function of the hydration degree) nanosilicas were analyzed using nitrogen adsorption-desorption, gelatin adsorption, small angle X-ray scattering (SAXS), TEM, and infrared (FTIR) spectroscopy. Equilibrium adsorption of DOX onto cA-300 and cA-300/HSA was analyzed using ultraviolet-visible light spectroscopy. Photon correlation spectroscopy was used to analyze the particle size distribution in aqueous suspensions with various contents of components. DOX more strongly bound to HSA than silica also affects structure of interfacial water layers that depends on dispersion media because chloroform as immiscible with water changes the water organization to enlarge water structures. In aqueous media, DOX alone remains mainly in the form of nano/microparticles (50â¯nm-2⯵m in size). However, with the presence of cA-300, cA-300/HSA, and HSA alone DOX transforms into pure nano-sized structures. These effects are explained by effective bonding of DOX to HSA having good transport properties with respect to drug molecules/ions that exceed similar properties of nanosilica alone, but cA-300/HSA can be a more effective composite as a drug carrier.
Asunto(s)
Antibióticos Antineoplásicos/metabolismo , Doxorrubicina/metabolismo , Portadores de Fármacos/química , Nanopartículas/química , Albúmina Sérica Humana/metabolismo , Dióxido de Silicio/metabolismo , Antibióticos Antineoplásicos/química , Doxorrubicina/química , Humanos , Albúmina Sérica Humana/química , Dióxido de Silicio/química , SuspensionesRESUMEN
AIM: To study toxicity of lypooligosaccharides (LOS) of non-typable Haemophilus influenzae (NTHi) strain and products of their detoxication obtained using different reagents. MATERIALS AND METHODS: LPS was obtained from the NTHi strain grown on solid brain-heart infusion nutrient medium using previously described method of isolation and purification of LOS. Obtained LPS was treated in same conditions by one of the 3 detoxifying agents: anhydrous hydrazine (AH), alkali (NaOH), and hydrochloric hydroxylamine (HH). Toxicity of LOS and its detoxified derivatives was measured on outbred mice which were administered 0.5 ml of actinomycin D intraperitoneally 1 day before immunization. Death of animals was assessed on day 2 after immunization. Polyacrylamide gel electrophoresis was used for study the influence of detoxifying agents on physico-chemical properties of LOS. RESULTS: As a result of treatment of NTHi No.45 LOS by different detoxifying agents, 3 preparations of detoxified LOS (d-LOS) and 3 preparations from precipitates (nd-LOS) were obtained. Preparation d-LOSAH was the least toxic. Toxic properties of nd-LOSHH did not reliably change. PAAG electrophoresis showed that virtually all detoxified preparations were characterized by higher migration of lypooligosaccharide components compared to original LOS of NTHi No. 45, which indicates the lowering of LOS molecular weight after treatment by detoxifying agents, associated with elimination of lipid A higher fatty acids. CONCLUSION: Analysis of effects of detoxifying agents indicates the need to select individual conditions for treatment by each of them.
Asunto(s)
Infecciones por Haemophilus/prevención & control , Vacunas contra Haemophilus/inmunología , Vacunas contra Haemophilus/toxicidad , Haemophilus influenzae/inmunología , Lipopolisacáridos/inmunología , Lipopolisacáridos/toxicidad , Álcalis/química , Animales , Infecciones por Haemophilus/inmunología , Infecciones por Haemophilus/microbiología , Vacunas contra Haemophilus/química , Humanos , Hidrazinas/química , Hidroxilamina/química , Dosificación Letal Mediana , Lipopolisacáridos/química , RatonesRESUMEN
Baikal planaria from genus Bdellocephala were typified using rDNA locus coding 5'--end domain of 18S ribosome RNA. Five colour forms of 24 possible variants that differ in diapason 0-1.3% of genotype were determined by comparative analysis of nucleotide sequences. The authors use back colour--one of the most variable and typical character in the given group--to collect material for investigation. It allows to minimize the size of investigation sample and at the same time to cover maximum variability of Bdellocephala. One of the positive result of molecular typification of colour forms was a discovery of unique individuals that belong to new species. Karyological analysis of colour forms shows variations in chromosome numbers that divide planaria into 3 groups (2n = 20, 24, 26). Comparative analysis of morphological and ecological characters and karyotypes of some forms united by the same genotype allows to distinguish them as separate species. Criteria of modern phenetic system of Baikal planaria are discussed.
Asunto(s)
Planarias/genética , Animales , Secuencia de Bases , ADN de Helmintos/clasificación , ADN de Helmintos/genética , ADN de Helmintos/aislamiento & purificación , Agua Dulce , Genotipo , Cariotipificación , Datos de Secuencia Molecular , Planarias/clasificación , Reacción en Cadena de la Polimerasa/métodos , ARN de Helminto/clasificación , ARN de Helminto/genética , ARN Ribosómico 18S/clasificación , ARN Ribosómico 18S/genética , Siberia , Especificidad de la EspecieRESUMEN
Ethonium in solution and on the surface of surgical threads displays different antistaphylococcal activity in the presence of biological fluids: under the influence of bile, it decreases essentially, blood serum--decreases to a less degree, urine doesn't change it. A conclusion is made that for optimal use of the ethonium and surgical threads modified with ethonium it is necessary to take into account the location of a pathological focus.
Asunto(s)
Antibacterianos/farmacología , Bilis/fisiología , Actividad Bactericida de la Sangre/fisiología , Modelos Biológicos , Compuestos de Amonio Cuaternario/farmacología , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Infección de la Herida Quirúrgica/prevención & control , Suturas , Orina/fisiología , Antibacterianos/administración & dosificación , Medios de Cultivo , Humanos , Técnicas In Vitro , Compuestos de Amonio Cuaternario/administración & dosificación , Staphylococcus aureus/patogenicidadRESUMEN
The authors suggest a unified system of designation of type--sizes of surgical suture materials of various nature and structure, which removes the existing discrepancy between the numbering of foreign and Soviet threads as well as of Soviet threads produced by different enterprises of the country. Introduction of the new system of metric sizes of the suture threads will allow surgeons to be properly orientated in the choice of the necessary suture material and make easier the work of services engaged in the development and realization of surgical suture materials.