63 research outputs found

    Anticonvulsant effects of hesperetin in animal model of pentylenetetrazole-induced-seizures

    Get PDF
    Background and objective: Hesperetin as the main flavonoid in citrus possesses various pharmacological properties including anti-oxidant and anti-inflammatory effects. In this study, the effects of hesperetin on seizures behavior and its function on total antioxidant capacity and lipid peroxidation has been investigated in pentylenetetrazol (PTZ)-induced seizures model. Materials and methods: In this experimental study, thirty-five mice were divided into 5 experimental groups as control, saline and hesperetin at doses of 10, 20 or 50 mg/kg. Animals received orally the related interventions for 7 days. On day 7, 30 minutes after oral gavage, convulsion was induced by single intraperitoneal (i.p.) injection of PTZ at dose of 60 mg/kg. After recording of convulsion behaviors including latency to myoclonic jerks, latency and duration of generalized tonic-clonic seizures, time to death, measuring of Ferric Reducing Antioxidant Power (FRAP) and Thiobarbituric acid reactive substances (TBARS) carried out in hippocampus tissues. Findings: Pretreatment with hesperetin at dose of 50 mg/kg significantly increased the latency of myoclonic jerks (hesperetin 50: P=0.0323) and generalized tonic-clonic seizures (hesperetin 10: P= 0.0003, hesperetin 20: 0.0017, hesperetin 50: P=0.0040). Hesperetin application at dose of 10 mg/kg significantly reduced the levels of TBARS compared to control group. Any significant difference in FRAP levels was not observed between different experimental groups. Conclusion: The results of study indicate that hesperetin might be effective as supplementary treatment in epilepsy disorder

    TonEBP suppresses adipogenesis and insulin sensitivity by blocking epigenetic transition of PPAR gamma 2

    Get PDF
    TonEBP is a key transcription factor in cellular adaptation to hypertonic stress, and also in macrophage activation. Since TonEBP is involved in inflammatory diseases such as rheumatoid arthritis and atherosclerosis, we asked whether TonEBP played a role in adipogenesis and insulin resistance. Here we report that TonEBP suppresses adipogenesis and insulin signaling by inhibiting expression of the key transcription factor PPAR gamma 2. TonEBP binds to the PPAR gamma 2 promoter and blocks the epigenetic transition of the locus which is required for the activation of the promoter. When TonEBP expression is reduced, the epigenetic transition and PPAR gamma 2 expression are markedly increased leading to enhanced adipogenesis and insulin response while inflammation is reduced. Thus, TonEBP is an independent determinant of adipose insulin sensitivity and inflammation. TonEBP is an attractive therapeutic target for insulin resistance in lieu of PPAR gamma agonistsopen0

    Synaptic Neurotransmission Depression in Ventral Tegmental Dopamine Neurons and Cannabinoid-Associated Addictive Learning

    Get PDF
    Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction

    Global maps of soil temperature

    Get PDF
    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Perception of medical students participated in community-oriented medical education in Kermanshah (2007-2011)

    No full text
    Introduction: Physicians have a fundamental role in the health system. Therefore, investigation of different medical education approaches would have a major impact on improving the quality of education. The aim of this study was investigating the performance of community-based education center of Kermanshah from the viewpoint of medical interns. Methods: In this cross sectional analytic study, medical interns who were trained in community-oriented education center (n=175) over one month were enrolled and completed the researcher built questionnaire. Alpha reliability was 0.88 and its content validity was confirmed by the approval of five faculty members who were expert in the field of education. Data was analyzed by SPSS software and using of descriptive statistics, ANOVA and Friedman tests.  Results: Based on the viewpoint of our participants, community oriented education were desirable compare to education in hospital in terms of quality of education (42/4%), experienced of practical tips (48/3%), observing different cases (57/2%), preventive medicine education (55/6%)and time for communicating about patient (74%). Among reasons of difference between training in the COME center  compare to teaching hospitals, "possibility of learning of practical tips" was considered more important than other reasons (P<0.05). Conclusion: In this study, most participants have evaluated the training performance of the COME center as good and also more useful compared to training in teaching hospitals. Reinforcing of COME centers could be a priority in making future educational policies

    Time-frequency analysis of diesel engine noise using biodiesel fuel blends

    No full text
    In recent years, biodiesel has been demonstrated to offer a suitable level of reliability and attracted the attention of many researchers. Accordingly, various studies have been carried out to account for the biodiesel production and application, producing valuable reports and findings. In this research study, the effects of biodiesel on engine noise were studied on the basis of a time-frequency analysis. To do so, the acquired acoustic signal was initially filtered and denoised. Then the signal was transferred to the time-frequency SPL domain using short-time Fourier transform. In the A weighted signal, the SPL of all treatments were compared using an innovative visual technique. In this novel approach, the values of area percentages of the obtained SPL in the time-frequency domain were used to compare the propagated noise due to variables. The method revealed a consistent trend for all fuel blends at all engine rotational speeds. The analysis results showed that B10 (10% methyl/ethyl ester and 90% diesel fuel) and B30 had the lowest and highest A-Weighted SPL, respectively. Additionally, it was found that the engine had a maximum sensitivity for all fuel blends at an engine rotation speed of 1600 RPM. Moreover, Z-weighted (linear) signal processing was used to investigate what happens in a complete thermodynamic cycle at 1600 RPM. The developed time- frequency methodology successfully exposed all of the important acoustic events of the engine. The results of this study showed that the most effective acoustic events in engine noise were combustion, piston slap, and outlet valve closing. Furthermore, higher percentages of biodiesel blends resulted in longer combustion duration
    corecore