1,487 research outputs found
MODULATION OF THE L-TYPE CALCIUM CHANNEL CAV1.2 BY NOCICEPTIN AND ITS RECEPTOR NOP1
The endogenous neuropeptide nociceptin (N/OFQ) and its receptor, the nociceptin receptor (NOP1), are highly expressed in the hippocampus, where they regulate learning and memory by inhibiting synaptic transmission and plasticity. The L-type calcium channel (LTCC) Cav1.2 is also expressed in the hippocampus and is one of the major sources of Ca2+ in the postsynaptic compartment of neurons. Activation of Cav1.2 regulates memory and learning-associated biochemical changes through activation of cAMP response element-binding protein (CREB) and NMDA receptor-independent long-term potentiation (LTP). It has previously been shown that activation of NOP1 receptor by nociceptin downregulates LTCCs as well as other voltage gated calcium channels in hippocampal neurons [2], but little is known regarding the molecular mechanisms of this modulation. We show that Cav1.2 and NOP1 receptor form a complex and co-immunoprecipitate from transfected tsA201 cells and from hippocampal brain tissue. Calcium imaging of cultured rat hippocampal neurons treated with nociceptin (1uM) and depolarized with 40mM KCl revealed a significant decrease in calcium influx. Treatment with the LTCC blocker, Nifedipine showed that calcium influx is partially mediated by Cav1.2. Subsequent imaging of cultured rat hippocampal neurons treated with nociceptin (100nM) and depolarized with 40mM KCl revealed a significant decrease in CREB phosphorylation in the nucleus, an important step for neuronal plasticity. Treatments with Nifedipine and NMDA receptor antagonists (MK-801 and APV) indicate that the activation of nuclear p-CREB results in part from the activation of Cav1.2, and is NMDA receptor-independent. Our data provide novel insights into the mechanisms by which the endogenous neuropeptide nociceptin affects hippocampal neuron function. Ultimately, this could identify new strategies for the alleviation of memory disorders
Prevalence of Obesity and Correlated Hypertension and Hyperglycaemia Status among Participants of a Health Screening Programme in Inanam Sub-district, Kota Kinabalu, Sabah, Malaysia
Obesity is a known risk factor for non-communicable diseases, including hypertension and diabetes mellitus, with Malaysia having the highest prevalence of obesity among Southeast Asian countries. Additionally, the delivery of medical services to the rural communities remains challenging despite efforts to increase accessibilities to the healthcare facilities. Therefore, regular health screening programmes specifically aiming at these communities are necessary for early diagnosis and intervention to prevent complications while improving the patients' quality of life. A health screening programme was conducted in a sub-district of Kota Kinabalu, Sabah, Malaysia, where 50 participants were examined for general obesity based on body mass index (BMI) together with central obesity according to waist circumference (WC) and waist-to-hip ratio (WHR). Bioelectrical impedance analysis was performed to estimate body fat percentage (fat%) and body fat mass, along with the measurement of systolic blood pressure (SBP), diastolic blood pressure (DBP), and capillary blood glucose. The median age of the participants was 39.50 years. The prevalence of general obesity, central obesity based on WC and WHR, hypertension, and hyperglycaemia was 28%, 78%, 74%, 24%, and 20%, respectively. Both fat% and fat mass had positive correlations to the BMI (fat%: r = 0.656, p = 0.001; fat mass: r = 0.868, p = 0.001) and WC (fat%: r = 0.505, p = 0.001; fat mass: r = 0.761, p = 0.001). DBP had positive correlations with the BMI (r = 0.390, p = 0.005), WC (r = 0.467, p = 0.001), and WHR (r = 0.331, p = 0.019), while SBP had a positive correlation only with WC (r = 0.341, p = 0.015). Conversely, capillary blood glucose had no significant correlation with either BMI, WC, or WHR. The higher prevalence of central obesity among participants of the health screening program compared to the national level should raise concern among the healthcare providers regarding the future risk for hypertension and hyperglycaemia in this community
2018-2019 Winds and Percussion
Featuring students from the woodwind and percussion studios under the direction of Associate Professor Eric Van der Veer Varner and Distinguished Artist in Residence Ted Atkatz.https://spiral.lynn.edu/foc-events/1027/thumbnail.jp
Chlorella vulgaris biomass enriched by biosorption of polyphenols
Cell walls of microalgae are variable and contain non-specific domains where different molecules can bind. The enrichment of microalgal biomass with nutrients through adsorption can be an interesting process for the food and feed industry. In this study, naturally occurring polyphenols ((+)-catechin, ()-epicatechin, quercetin, rutin and xanthohumol) were adsorbed onto nonliving cells of freshwater microalgae Chlorella vulgaris. The essential adsorption parameters such as biomass dose and contact time were examined and the adsorption was quantified with Langmuir, Sips and DubininRadushkevich adsorption isotherms. The evaluation of isotherms proved the highest affinity towards Chlorella vulgaris biomass for xanthohumol and quercetin. The biosorption mechanism of Chlorella vulgaris biomass was well described by a pseudo second order kinetic model, with a high regression coefficient. The polyphenol-enriched microalgal biomass was also evaluated for its antioxidant activity. The highest antioxidant activity was detected in the case of biomass enriched with quercetin (77.5% of decolorized DPPH).The financial support by the Ministry of Education, Youth and Sports of the Czech Republic through grant MSM6046137305 is gratefully acknowledged. Cristina Quintelas is thankful to Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) for funding the CEB researcher unit at the University of Minho and thanks the Project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN and FEDER
The RNA-binding protein hnRNP K mediates the effect of BDNF on dendritic mRNA metabolism and regulates synaptic NMDA receptors in hippocampal neurons
Brain-derived neurotrophic factor (BDNF) is an important mediator of long-term synaptic potentiation (LTP) in the hippocampus. The local effects of BDNF depend on the activation of translation activity, which requires the delivery of transcripts to the synapse. In this work, we found that neuronal activity regulates the dendritic localization of the RNA-binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K) in cultured rat hippocampal neurons by stimulating BDNF-Trk signaling. Microarray experiments identified a large number of transcripts that are coimmunoprecipitated with hnRNP K, and about 60% of these transcripts are dissociated from the protein upon stimulation of rat hippocampal neurons with BDNF. In vivo studies also showed a role for TrkB signaling in the dissociation of transcripts from hnRNP K upon high-frequency stimulation (HFS) of medial perforant path-granule cell synapses of male rat dentate gyrus (DG). Furthermore, treatment of rat hippocampal synaptoneurosomes with BDNF decreased the coimmunoprecipitation of hnRNP K with mRNAs coding for glutamate receptor subunits, Ca2+- and calmodulin-dependent protein kinase IIβ (CaMKIIβ) and BDNF. Downregulation of hnRNP K impaired the BDNF-induced enhancement of NMDA receptor (NMDAR)-mediated mEPSC, and similar results were obtained upon inhibition of protein synthesis with cycloheximide. The results demonstrate that BDNF regulates specific populations of hnRNP-associated mRNAs in neuronal dendrites and suggests an important role of hnRNP K in BDNF-dependent forms of synaptic plasticity.publishe
Spatial Variations of Heavy Metals in the Soils of Vegetable-Growing Land along Urban-Rural Gradient of Nanjing, China
China has experienced rapid urbanization in recent years. The acceleration of urbanization has created wealth and opportunity as well as intensified ecological and environmental problems, especially soil pollution. Our study concentrated on the variation of heavy metal content due to urbanization in the vegetable-growing soil. Laws and other causes of the spatial-temporal variation in heavy metal content of vegetable-growing soils were analyzed for the period of urbanization in Nanjing (the capital of Jiangsu province in China). The levels of Cu, Zn, Pb, Cd and Hg in samples of vegetable-growing soil were detected. The transverse, vertical spatio-temporal variation of heavy metals in soil was analyzed on the base of field investigations and laboratory analysis. The results show that: (1) in soil used for vegetable production, the levels of heavy metals decreased gradually from urban to rural areas; the levels of the main heavy metals in urban areas are significantly higher than suburban and rural areas; (2) the means of the levels of heavy metals, calculated by subtracting the sublayer (15–30 cm) from the toplayer (0–15 cm), are all above zero and large in absolute value in urban areas, but in suburban and rural areas, the means are all above or below zero and small in absolute value. The causes of spatial and temporal variation were analyzed as follows: one cause was associated with mellowness of the soil and the length of time the soil had been used for vegetable production; the other cause was associated with population density and industrial intensity decreasing along the urban to rural gradient (i.e., urbanization levels can explain the distribution of heavy metals in soil to some extent). Land uses should be planned on the basis of heavy metal pollution in soil, especially in urban and suburban regions. Heavily polluted soils have to be expected from food production. Further investigation should be done to determine whether and what kind of agricultural production could be established near urban centers
Formation and interactions of cold and ultracold molecules: new challenges for interdisciplinary physics
Progress on researches in the field of molecules at cold and ultracold
temperatures is reported in this review. It covers extensively the experimental
methods to produce, detect and characterize cold and ultracold molecules
including association of ultracold atoms, deceleration by external fields and
kinematic cooling. Confinement of molecules in different kinds of traps is also
discussed. The basic theoretical issues related to the knowledge of the
molecular structure, the atom-molecule and molecule-molecule mutual
interactions, and to their possible manipulation and control with external
fields, are reviewed. A short discussion on the broad area of applications
completes the review.Comment: to appear in Reports on Progress in Physic
New Trends in Impedimetric Biosensors for the Detection of Foodborne Pathogenic Bacteria
The development of a rapid, sensitive, specific method for the foodborne pathogenic bacteria detection is of great importance to ensure food safety and security. In recent years impedimetric biosensors which integrate biological recognition technology and impedance have gained widespread application in the field of bacteria detection. This paper presents an overview on the progress and application of impedimetric biosensors for detection of foodborne pathogenic bacteria, particularly the new trends in the past few years, including the new specific bio-recognition elements such as bacteriophage and lectin, the use of nanomaterials and microfluidics techniques. The applications of these new materials or techniques have provided unprecedented opportunities for the development of high-performance impedance bacteria biosensors. The significant developments of impedimetric biosensors for bacteria detection in the last five years have been reviewed according to the classification of with or without specific bio-recognition element. In addition, some microfluidics systems, which were used in the construction of impedimetric biosensors to improve analytical performance, are introduced in this review
Glucocorticoid enhancement of memory requires arousal-induced noradrenergic activation in the basolateral amygdala
Considerable evidence indicates that glucocorticoid hormones enhance the consolidation of long-term memories for emotionally arousing experiences but not that for less arousing or neutral information. However, previous studies have not determined the basis of such arousal-induced selectivity. Here we report the finding that endogenous noradrenergic activation of the basolateral complex of the amygdala (BLA) induced by emotional arousal is essential in enabling glucocorticoid memory enhancement. Corticosterone administered immediately after object recognition training enhanced 24-h memory of naïve male rats but not that of rats previously habituated to the training context in order to reduce novelty-induced emotional arousal. The β-adrenoceptor antagonist propranolol administered either systemically or into the BLA blocked the corticosterone-induced memory enhancement. Further, in habituated rats, corticosterone activated BLA neurons, as assessed by phosphorylated cAMP response element binding (pCREB) immunoreactivity levels, and enhanced memory only when norepinephrine release was stimulated by administration of the α2-adrenoceptor antagonist yohimbine. These findings strongly suggest that synergistic actions of glucocorticoids and emotional arousal-induced noradrenergic activation of the BLA constitute a neural mechanism by which glucocorticoids may selectively enhance memory consolidation for emotionally arousing experiences.
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