2,621 research outputs found
Evaluation of the inhibitory synergic effects of the Persian Gulf brittle star extract and taxol on ovarian cancer A2780cp
Paclitaxel is a current standard chemotherapeutic drug for ovarian cancer with several side effects. Recurrences of drug resistant clones have been considered the serious problem in the failure of chemotherapy. Medicinal marine natural products have been intensively proposed as diverse chemotherapeutic agents. Therefore there is an affinity to find efficient modality to overwhelm ovarian cancer chemo resistance complication. Here we examine whether brittle star extract as marine echinoderm natural resources can remarkably improve the cytotoxicity of paclitaxel in human ovarian cancer. MTT (dimethyl thiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay, PI (Propodium Iodide) assay, DAPI (4', 6-diamidino-2-phenylindole) staining, Acridine orange staining, caspase-3 and caspase-9 were performed to investigate cytotoxic effect. We found that a combination of sub-toxic concentrations of brittle star methanolic extract (lower than IC_50) can significantly enhance ovarian cell growth inhibition and intrinsic apoptosis pathways induced by paclitaxel. Consequently a combination of paclitaxel and brittle star extract may offer novel innovative strategies for ovarian cancer chemotherapy
Survival probability in Generalized Rosenzweig-Porter random matrix ensemble
We study analytically and numerically the dynamics of the generalized
Rosenzweig-Porter model, which is known to possess three distinct phases:
ergodic, multifractal and localized phases. Our focus is on the survival
probability , the probability of finding the initial state after time
. In particular, if the system is initially prepared in a highly-excited
non-stationary state (wave packet) confined in space and containing a fixed
fraction of all eigenstates, we show that can be used as a dynamical
indicator to distinguish these three phases. Three main aspects are identified
in different phases. The ergodic phase is characterized by the standard
power-law decay of with periodic oscillations in time, surviving in the
thermodynamic limit, with frequency equals to the energy bandwidth of the wave
packet. In multifractal extended phase the survival probability shows an
exponential decay but the decay rate vanishes in the thermodynamic limit in a
non-trivial manner determined by the fractal dimension of wave functions.
Localized phase is characterized by the saturation value of ,
finite in the thermodynamic limit , which approaches
in this limit.Comment: 21 pages, 12 figures, 61 reference
The Estimation Lie Algebra Associated with Quantum Filters
International audienceWe introduce the Lie algebra of super-operators associated with a quantum filter, specifically emerging from the Stratonovich calculus. In classical filtering, the analogue algebra leads to a geometric theory of nonlinear filtering which leads to well-known results by Brockett and by Mitter characterizing potential models where the curse-of-dimensionality may be avoided, and finite dimensional filters obtained. We discuss the quantum analogue to these results. In particular, we see that, in the case where all outputs are subjected to homodyne measurement, the Lie algebra of super-operators is isomorphic to a Lie algebra of system operators from which one may approach the question of the existence of finite-dimensional filters
Cytotoxic and antioxidant effect of chrysin on neonate mouse spermatogenic stem cells
Background: So far, many plants have been used for the treatment of infertility. Several studies have revealed that chrysin (as an active metabolite) improves animals' reproduction. Therefore, the objective of this study was to evaluate the effect of chrysin on Balb/C mice spermatogenic stem cells. Materials and Methods: In this in vitro experimental study Balb/C neonate spermatogonia stem cells cultured in DMEM-F12 medium were treated with various concentrations of chrysin (2.5, 5, 10, 20, 40 µg/ml) for 6 and 12 days. Then the cytotoxicity was assessed using MTT, Akredin orange/Propodium Idid, DAPI and antioxidant concentration DCF-DA tests. Results: Chrysin showed no remarkable cytoxicity in concentrations less than 5 µg/ml. While, after 6 days the viability of cells treated with chrysin 10, 20 and 40 µg/ml was decreased to 30, 45 and 56 (P<0.05 and P<0.001, respectiely); after 12 days the viability of cells was decreased to 44, 56 and 65 (P<0.05, P<0.01 and P<0.001, respectiely). DCF-DA results revealed a 80 antioxidant capacity of chrysin in 5 and 2.5µg/ml concentrations. Conclusion: Lower concentrations of chrysin has protective effect on Balb/C mice spermatogenic through improving cell viability, decreasing cells apoptosis and inhibiting free radicals
The effect of Fig on antioxidant and oxidative parameter of normal young men in a clinical trial study
Background and aim: Today, due to the increased production of free radicals such as pollution, there is a need to a good antioxidant resource. Fig which is one of the fruit mentioned in the Qur'an, may prevent increased production of free radicals because of its rich content of antioxidants. This study was aimed to study the effect of using figs on oxidant and antioxidant parameters on healthy young men. Materials and methods: In this clinical trial, 74 healthy male students were chosen randomly and divided into two groups of test and control. Age range was 18- 40, and residency in university’s dormitories were entry criteria and disease, smoking and taking other complements were exclude criteria. The test group receive daily 120 g dried fig for four weeks. Blood samples were obtained from two groups at beginning of study and after 4 weeks. Total Antioxidant Capacity (TAC) was measured by FRAP method, activity of GGT and the rate of Fe were matured by auto analyzer system BT 3000. Results: results indicate that Fe level has a significant decrease as an oxidative parameter in the test group (N= 37) after four weeks of interference (p=005/0). GGT and TAC levels showed a significant increase as antioxidant parameters in the test group after four weeks of interference (p= 0/001). Conclusion: Considering the significant decrease in Fe level as the oxidative parameter and substantial increase in GGT and TAC level as the antioxidant parameters, Figs can play an effective and useful role in increasing the antioxidant defend of the body against free radicals and so decrease damages caused by oxidative stress
Lecturers’ Compliance with Quality Assurance Mechanisms in Public Universities in Delta State
The study investigated the extent to which lecturers’ complied with quality assurance mechanisms in public universities in Delta State. Two objectives, two research questions and two hypotheses guided the study. The descriptive survey research design was adopted. The population of the study consisted of 1,299 lecturers and 6,826 students from the public universities in Delta State. A sample of 260 lecturers and 409 students representing 20% and 6% respectively, of the population was obtained using the proportionate random sampling technique. The instrument used for data collection was a researchers’ made questionnaire titled “Compliance with Quality Assurance Mechanisms Questionnaire (CQAMQ). The Cronbach Alpha method was used to determine the internal consistency of the items and it yielded a result of 0.76 and 0.97 for A and B respectively. The researchers and two assistants distributed 669 copies of the questionnaire and successfully collected 628 copies of the questionnaire administered. The research questions were analyzed using the mean, standard deviation and rank order statistics, while the hypotheses were tested using z-test at 0.05 level of significance. It was found that lecturers in public universities in Delta State complied with measurement and evaluation of students learning outcome and the use of interactive teaching and learning method in the classroom to a high extent. The findings revealed that lecturers’ compliance with measurement and evaluation of students learning outcomes in public universities in Delta State is high. Based on the findings, it was concluded that lecturers complied with the quality assurance mechanisms to a high extent, it was therefore recommended that the university management should formulate a policy that will make lecturers sustain the strategy of assessing the learning outcome ofstudents and organize more lectures and seminars on how lecturers can sustain the strategies in the use of interactive teaching and learning methods in the classroom
Comparison of ferment sugars, produce hemolysis and measuring growth in methicillin-resistant and methicillin-sensitive Staphylococcus aureus isolates from inpatients and healthcare workers in Gorgan Hospitals, North of Iran
The mec A gene in Staphylococcus aureus leads to production of new penicillin-binding protein called PBP2a.This change may follow some changes in other phenotypes. The aim of this study was the comparison of Ferment Sugars, Produce Hemolysis and Measuring Growth in MRSA and MSSA isolates. 188 Staphylococcus aureus isolates separated from inpatients and healthcare workers (healthy carriers)were studied.Bacterialcultures in blood agar environment at 37°C during 24h and at 4°C during other 24h were applied for studying hemolysis. Sugar fermentation carried out in phenol red Broth medium, containing glucose, galactose, arabinose, fructose, xylose, ramnose, mannose, sucrose, trehalose, raffinose or maltose. For determining bacterial growth,bacterial concentration of 103was taken each hour during 12 cultured in MHAand colonies were counted after 24h.The mean amount of hemolysis diameter in MRSA isolates was rather more than that of MSSA isolates. The difference between MRSA and MSSA isolates were significant as to fermenting ramnose, trehalose, galactose and xylose. The mean rate of growth in MRSAwere significantly different from that of MSSAisolates (p<0.05).Resistance to methicillin in Staphylococcus aureus isolates accompanies the increase of ability to ferment sugars. This phenomenon may be one of reasons for increased pathogenicity of MRSA isolates; So results shows the logarithmic phase is longer in MRSA isolates, This may implicate that PBP2a production in methicillin-resistant isolates follows slowing down nutrients entrance into the bacterium that in turn may causes slow growth
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