22 research outputs found
High doses of medroxyprogesterone as the cause of disappearance of adherence of the zona pellucida to an oocyte
The zona pellucida (ZP) is an external glycoprotein membrane of oocytes of mammals and embryos in the early stage of their development. ZP first appears in growing ovarian follicles as an extracellular substance between the oocyte and granular cells. The zona pellucid markedly affects the development and maturation of the oocyte. The morphology of the ZP-oocyte complex allows a more precise determination of the oocyte maturity. According to numerous experimental studies, ZP is essential for preimplantation embryonic development of humans and other mammals. It prevents dispersion of blastomeres and enhances their mutual interactions. ZP is a dynamic structure responsible for the provision of nutrients to early forms of oocytes in mammals. The aim of the present study was untrastructural evaluation of the ZP-oocyte contact during inhibited ovulation. Female white rats (Wistar strain) received a suspension of medroxyprogesterone acetate (MPA) in incremental intramuscular bolus doses of 3.7Â mg (therapeutic dose), 7.4Â mg and 11.1Â mg. The animals were decapitated 5Â days after the administration of MPA. Ovarian sections were evaluated under a transmission electron microscope (TEM) Zeiss EM 900. Morphometric analysis of ZP was conducted using the cell imaging system by Olympus. In females exposed to therapeutic doses of MPA, ZP showed the structure of granular-fibrous reticulum of a medium electron density with single cytoplasmic processes originating from the surrounding structures. The oocyte cell membrane generated single, delicate processes directed toward ZP. Microvilli of the oocyte were short and thin. In the group receiving 7.4Â mg of MPA, ZP had the structure of a delicate, loose granular-fibrous reticulum, and the oocyte cell membrane generated single microvilli directed toward ZP. In both those groups, the close ZP-oocyte contact was observed. Otherwise, in the group exposed to the highest MPA doses (11.1Â mg), thicker and more numerous oocyte microvilli were found, which did not penetrate ZP matrix. They were dense, irregularly separated contour, forming a barrier between ZP and oocyte. The present findings are likely to suggest that MPA has inhibiting effects on the synthesis of binding proteins and causes the loss of the oocyte contact with ZP
A microfluidic device with fluorimetric detection for intracellular components analysis
An integrated microfluidic system that coupled lysis of two cell lines: L929 fibroblasts and A549 epithelial cells, with fluorescence-based enzyme assay was developed to determine ÎČ-glucocerebrosidase activity. The microdevice fabricated in poly(dimethylsiloxane) consists of three main parts: a chemical cell lysis zone based on the sheath flow geometry, a micromeander and an optical fibers detection zone. Unlike many methods described in literature that are designed to analyse intracellular components, the presented system enables to perform enzyme assays just after cell lysis process. It reduces the effect of proteases released in lysis process on determined enzymes. Glucocerebrosidase activity, the diagnostic marker for Gaucherâs disease, is the most commonly measured in leukocytes and fibroblasts using 4-methylumbelliferyl-ÎČ-D-glucopyranoside as synthetic ÎČ-glucoside. The enzyme cleavage releases the fluorescent product, i.e. 4-methylumbelliferone, and its fluorescence is measured as a function of time. The method of enzyme activity determination described in this paper was adapted for flow measurements in the microdevice. The curve of the enzymatic reaction advancement was prepared for three reaction times obtained from application of different flow rates of solutions introduced to the microsystem. Afterwards, determined ÎČ-glucocerebrosidase activity was recalculated with regard to 105 cells present in samples used for the tests. The obtained results were compared with a cuvette-based measurements. The lysosomal ÎČ-glucosidase activities determined in the microsystem were in good correlation with the values determined during macro-scale measurements
Does administration of non-steroidal anti-inflammatory drug determine morphological changes in adrenal cortex: ultrastructural studies
Rofecoxib (Vioxx© made by Merck Sharp & Dohme, the USA) is a non-steroidal anti-inflammatory drug which belongs to the group of selective inhibitors of cyclooxygenasis-2, i.e., coxibs. Rofecoxib was first registered in the USA, in May 1999. Since then the drug was received by millions of patients. Drugs of this group were expected to exhibit increased therapeutic action. Additionally, there were expectations concerning possibilities of their application, at least as auxiliary drugs, in neoplastic therpy due to intensifying of apoptosis. In connection with the withdrawal of Vioxx© (rofecoxib) from pharmaceutical market, attempts were made to conduct electron-microscopic evaluation of cortical part of the adrenal gland in preparations obtained from animals under influence of the drug. Every morning animals from the experimental group (15 rats) received rofecoxib (suspension in physiological saline)ânon-steroidal anti-inflammatory drug (Vioxx©, Merck Sharp and Dohme, the USA), through an intragastric tube in the dose of 1.25 mg during 8 weeks. In the evaluated material, there was found a greater number of secretory vacuoles and large, containing cholesterol and other lipids as well as generated glucocorticoids, lipid drops in cytoplasm containing prominent endoplasmic reticulum. There were also found cells with cytoplasm of smaller densityâespecially in apical and basal parts of cells. Mitochondria occasionally demonstrated features of delicate swelling. The observed changes, which occurred on cellular level with application of large doses of the drug, result from mobilization of adaptation mechanisms of the organism
Microfluidic devices â application in anticancer studies
A rapidly growing pharmaceutical industry requires faster and more efficient ways to find and test new drugs. One of the new method for cell culture and examining the toxic effects of drugs is application of microfluidic systems. They provide new types of microenvironments and new methods for investigation of anticancer therapy. The use of microsystems is a solution that gives the opportunity to reduce not only cost and time, but also a number of tests on animals. In this paper we present designed and fabricated hybrid microfluidic systems which are applicable for cell culture, cell based cytotoxicity assays and photodynamic therapy procedures. Polydimethylsiloxane (PDMS) and sodium glass were used for fabrication of microdevices. The designed geometry of the microdevices includes cell culture microchambers and a concentration gradient generator (CGG). The CGG enables to obtain diff erent concentrations of tested drugs in a single step, which is a significant simplification of cytotoxicity assay procedure. In the designed microsystems three various cell lines (normal and carcinoma) were cultured and analyzed
Application of Sentinel-2 and EnMAP new satellite data to the mapping of alpine vegetation of the Karkonosze Mountains
Effective assessment of environmental changes requires an update of vegetation maps as it is an indicator of both local and global development. It is therefore important to formulate methods which would ensure constant monitoring. It can be achieved with the use of satellite data which makes the analysis of hard-to-reach areas such as alpine ecosystems easier.
Every year, more new satellite data is available. Its spatial, spectral, time, and radiometric resolution is improving as well. Despite significant achievements in terms of the methodology of image classification, there is still the need to improve it. It results from the changing needs of spatial data users, availability of new kinds of satellite sensors, and development of classification algorithms. The article focuses on the application of Sentinel-2 and hyperspectral EnMAP images to the classification of alpine plants of the Karkonosze (Giant) Mountains according to the: Support Vector Machine (SVM), Random Forest (RF), and Maximum Likelihood (ML) algorithms. The effects of their work is a set of maps of alpine and subalpine vegetation as well as classification error matrices. The achieved results are satisfactory as the overall accuracy of classification with the SVM method has reached 82% for Sentinel-2 data and 83% for EnMAP data, which confirms the applicability of image data to the monitoring of alpine plants
New microfluidic device for lactate dehydrogenase (LDH) activity analysis
In this paper, we present cytotoxicity analysis (determination of lactate dehydrogenase â LDH activity performed in a designed and fabricated microfl uidic system. This method allowed for analysis of a supernatant collected from A549 (human lung cancer) and HT-29 (human colon cancer epithelial) cells, which were incubated for 24 h with selected compounds. LDH is an intracellular enzyme present in tissues, which is released into the supernatant caused by membrane damage or cell lyses. In our tests, LDH-Cytotoxicity Assay Kit (BioVision) was used. The toxic eff ect of drugs was measured in the developed microsystem made of PDMS (poly(dimethylsiloxane)). Analytical reaction took place in the special designed microchannel geometry. Then, the LDH activity was measured at 490 nm using spectrophotometer. In subsequent experiments, appropriate conditions for measurements using a microfl uidic system were chosen. It was found that the selected reagent is sensitive to temperature changes and light exposure. Reaction time in the microsystem was determined by changes of fl ow rates of reagents. Afterwards, for the various reaction time, the toxic eff ect of 5-fl uorouracil, celecoxib and 1,4-dioxane was performed. The obtained results were compared with the results carried out in 96-well plates. Based on these results, it was noted that the enzymatic reaction time in the microsystem is shorter than in 96-well plate. Moreover, the advantage of using microsystem is also the small amount of reagents
Photodynamic therapy procedures in the microfluidic system
Evaluation of the effi ciency of photodynamic therapy (PDT) in a hybrid microfl uidic culture system was studied. The geometry of the utilized microsystem for PDT procedures consists microchambers for cell culture and microchannels, which create a concentration gradient generator (CGG). 5-aminolevulinic acid (ALA) as a precursor of the photosensitizer was used. The geometry of the microchip allowed to test diff erent concentrations of ALA in a single assay. Evaluation of the effi ciency of photodynamic therapy was determined 24 hours after PDT procedure (irradiation with light which induced accumulated in carcinoma cells). The performed microsystem contained two independent micropatterns, that enables examination simultaneously various cell lines (carcinoma and normal) or various photosensitizers
Place of residence and age as variables differentiating health behaviours and perception of health by women past menopause
Introduction. Research on the meaning of health and health behaviors is important for the development of health education
programmes which should be tailored to the needs of patients.
Objective. The aim of the study is to determine whether the place of residence and age have an impact on health behaviours
and the perception of health by women past menopause.
Materials and method. A survey method and three research instruments were employed: authorsâ questionnaire, the
Health Behaviour Inventory and the Health Criteria List by JuczyĆski, and the Kupperman Index. The study was carried out
among a sample of 102 women after menopause hospitalised in a hospital in eastern Poland.
Results. The overall health behaviour indicator (HBI) in the study group was found to reach an average value of 80.1±12.7points.
A higher HBI indicator was found to be characteristic of urban rather than rural residents; however, there was no statistically
significant difference (p>0.05). The age of respondents did not differentiate statistically their health behaviours (p>0.05).
Women who reported their last menstruation before the age of 50 obtained higher results in the dimension of health
practices (HPs) than those whose last menstruation ceased after the age of 50 (p<0.05). The respondents attributed the
highest importance to health, understood as a property, a state and a goal. Statistically significant differences were observed
in the importance of the statement according to which health is a process of âbeing able to work without tension and stressâ,
as the respondents from urban areas assigned to it a higher average weight than those from rural areas (p< 0.05).
Conclusions. A higher overall HBI, as well as indicators for particular categories, were characteristic of women from urban
areas. Age did not significantly differentiate the womenâs health behaviours. Rural residents were dominant in the group
of women who rated their health to be very good or good. The respondents attributed the highest importance to health
understood as a property, state and goal
Hope of patients in the terminal phase of cancer and place of residence
Objective. The aim of the study is to compare the hope of rural and urban inhabitants in the terminal stage of a neoplastic disease covered by stationary hospice care.
Materials and method. The study was carried out among patients in the terminal phase of a neoplastic disease. They were patients of both 24-hour and daily palliative and hospice care units throughout the country. The study group consisted of 246 patients, average age â 59.5, the youngest respondent was 18 and the oldest â 90. The B. L. Block (NCN-36) test, prepared for people struggling with serious life-threatening diseases, was used. Comparison of the results with regard to the place of residence was based on the test Friedman ANOVA and Kendall compatibility factor. The general comparison of hope in individual dimensions and globally with the division into the degree of urbanization, was based on the Kruskal-Wallis test. Results. On the basis of factor analysis, 4 scales constructed from 8 items branch were distinguished. The following scales are used to study hope in the situational dimension â health, the telek-temporal dimension â goals, the spiritual dimension â religious beliefs and in the emotional-affective (affective) dimension â motivations.
Conclusions. The strength of hope in people in the terminal phase of cancer, residing in villages, settlements, small, medium and large cities, was similar and depended on its magnitude. Of all the manifestations of hope, the greatest variation in results occurred in the subjects when they encountered serious problems and difficulties. The inhabitants of medium-sized cities were characterized by a higher hope at that time