ABSTRACT
The effects of ultrasmall (2-3 nm) gold nanoparticles on native epididymal sperm chromatin of CBAxC57BL/6 hybrid mice and 129/IMG mice with a mutation in the DNA-polymerase iota gene were studied. It is shown that for both mouse strains after sperm incubation in a solution containing Au nanoparticles, at 23, 37 and 60 degrees C for 30 min followed by 1 hour treatment in dithiothreitol solution, a decrease in the number of nuclei with fully decondensed chromatin was observed compared with the control. Though, the manifestation of this effect in the population of 129/IMG mice mature sperm, was weaker. Also we have demonstrated that sperm of both strains that were incubated in a sol of Au nanoparticles at 60 degrees C behave differently under the action of dithiothreitol. A considerable part (-80%) of sperm of CBAxC57BL/6 hybrid mice treated with Au nanoparticles showed high resistance to the action of dithiothreitol, whereas in the case of 129/IMG mice only -30% did, and a partial or complete chromatin decondensation takes place in the remaining sperm. In general, using the method of nuclear chromatin decondensation in vitro for the native sperm, the patterns that we have identified in earlier studies on previously demembranized sperm are confirmed.
Subject(s)
Chromatin/drug effects , Gold/pharmacology , Metal Nanoparticles/chemistry , Spermatozoa/drug effects , Animals , Gold/administration & dosage , Male , Metal Nanoparticles/adverse effects , Mice , Mice, Inbred C57BL , Mice, Inbred CBAABSTRACT
The response of ejaculated bovine spermatozoa to gold nanoparticles was studied by the standard method of nuclear chromatin decondensation in vitro. After the treatment of semen samples with a hydrosol containing gold nanoparticles with an average diameter of 3.0 nm and a concentration of 1 x 10(15) particles/mL, the ability of sperm nuclei to decondense in the presence of sodium dodecyl sulfate (SDS) and dithiothreitol (DTT) dramatically changed compared to the control. The frequencies of gametes with nondecondensed ("intact"), partially decondensed, and completely decondensed nuclei correlated as 40 : 32 : 28% and 0 : 36 : 64% in the experiment and the control, respectively. Moreover, the appearance of a sufficiently large number of gametes with destructed and almost completely destroyed nuclei was noticed in the spermatozoa treated with gold nanoparticles. This article suggests the putative mechanisms of action of ultrasmall gold nanoparticles on the structural and functional integrity of the deoxyribonucleoprotein (DNP) complex of mature male gametes.
Subject(s)
Chromatin/drug effects , Gold/adverse effects , Metal Nanoparticles/adverse effects , Spermatozoa/drug effects , Animals , Cattle , Cell Nucleus , Gold/administration & dosage , Male , Metal Nanoparticles/administration & dosage , Particle Size , Spermatozoa/cytologyABSTRACT
The response of the mouse male germ cells exposed to gold nanoparticles (approximately 2.5 nm) was studied. Our investigation demonstrates that treatment with Au nanoparticles for four days does not impair the architecture of the spermatogenic epithelium. Cytogenetic evaluation using micronucleus assay showed that gold nanoparticles can affect the chromosomes of early primary spermatocytes. However, gold nanoparticles did not induce chromosome abnormalities in spermatogonial stem cells. Further, the cauda epididymal sperm was isolated on the 14th day after treatment and was incubated in SDS solution (Na sodium dodecyl) and then in a solution containing DTT (dithiothreitol) to induce nuclear chromatin decondensation. Observations showed that after four days of treatment of spermiogenic (postmeiotic) cells with gold nanoparticles the decondensation process had no differences from the control. On the contrary, in the experiment with the same cells and period of fixation but with a single exposure to gold nanoparticles, the number of mature gametes with totally decondensed nuclei reached 100% as opposed to 44% in the controls.
Subject(s)
Gold/pharmacology , Metal Nanoparticles , Spermatogenesis/drug effects , Spermatogonia/drug effects , Animals , Chromatin/drug effects , Dithiothreitol/pharmacology , Epididymis/cytology , Epididymis/drug effects , Epithelium/drug effects , Male , Mice , Mice, Inbred C57BL , Sodium Dodecyl Sulfate/pharmacologyABSTRACT
The possibility of one-step creating of pH-sensitive mesostructured silica-based nanocontainers with exceptionally high payload using associates of two antiseptics (including hydrolyzable one) as templates is demonstrated. The effects of the template nature and the conditions of the sol-gel process on the porous structure of silica nanocontainers are studied and discussed. The kinetics of the templating drug release from such containers is studied and some features of this process are analyzed. It is shown that the drug release rate can be tuned by varying the medium pH. The bactericidal activity of two encapsulated antiseptics against the Staphylococcus aureus is evaluated in vitro by agar diffusion method with replacement of agar with agarose. The diameters of the inhibition zones for silica-based containers loaded with antiseptics increased with the pre-diffusion time at 4⯰C. At the same time, empty containers (after elimination of antiseptics by etching) did not reveal any bactericidal properties.
Subject(s)
Benzalkonium Compounds/pharmacology , Decamethonium Compounds/pharmacology , Drug Carriers/chemistry , Drug Liberation , Nanoparticles/chemistry , Silicon Dioxide/chemistry , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Benzalkonium Compounds/chemistry , Decamethonium Compounds/chemistry , Porosity , Surface PropertiesABSTRACT
Frontotemporal degeneration is a frequent cause of presenile dementia that makes up from 5 to 17% of autopsy-confirmed cases developed at the age of 70 years. Authors report a case of this disease, discuss the possible causes of its development and present the results of diffusion tensor magnetic resonance tractography. Clinical features of this case are practically isolated speech disturbance with the most likely domination of a semantic variant of primary progressive aphasia. Magnetic-resonance imaging has an important practical significance for this pathology due to the possibility of assessing atrophic zones. The use of DTI-tractography allows to extend diagnostic possibilities.