Search results for "AMA"
showing 10 items of 8558 documents
Nitric oxide/cGMP signaling via guanylyl cyclase isoform 1 modulates glutamate and GABA release in somatosensory cortex of mice
2017
Abstract In hippocampus, two guanylyl cyclases (NO-GC1 and NO-GC2) are involved in the transduction of the effects of nitric oxide (NO) on synaptic transmission. However, the respective roles of the NO-GC isoforms on synaptic transmission are less clear in other regions of the brain. In the present study, we used knock-out mice deficient for the NO-GC1 isoform (NO-GC1 KO) to analyze its role in the glutamatergic and GABAergic neurotransmission at pyramidal neurons in layers II/III of somatosensory cortex. NO-GC1 KO slices revealed reduced frequencies of miniature excitatory- and inhibitory-postsynaptic currents, increased paired-pulse ratios and decreased input–output curves of evoked signa…
Melatonin reduces inflammatory response in human intestinal epithelial cells stimulated by interleukin‐1β
2019
Melatonin is the main secretory product of the pineal gland, and it is involved in the regulation of periodic events. A melatonin production independent of the photoperiod is typical of the gut. However, the local physiological role of melatonin at the intestinal tract is poorly characterized. In this study, we evaluated the anti-inflammatory activities of melatonin in an in vitro model of inflamed intestinal epithelium. To this purpose, we assessed different parameters usually associated with intestinal inflammation using IL-1 beta-stimulated Caco-2 cells. Differentiated monolayers of Caco-2 cells were preincubated with melatonin (1 nmol/L-50 mu mol/L) and then exposed to IL-1 beta. After …
Prevalence of Extended Spectrum Beta Lactamase Producing Bacteria in Two Surgical Wards of a General Hospital
2019
Abstract Colonisation of gastrointestinal tract by extended spectrum beta lactamase (ESBL)-producing Gram-negative bacteria is a source for infections. The present work is a prospective study in Latvia aimed to determine the role of two surgical profile wards in transmission of ESBL-producing bacteria. Differences between hospital wards were not analysed due to low number of patients. We have also determined a correlation between the duration of hospitalisation and risk of ESBL colonisation. Tests for ESBL-producing bacteria were made twice for 136 patients — upon admission and upon discharge from the hospital. Of them, 21 (15.4%) patients already were ESBL-positive at the time of admission…
The effect of organic solvents on selected microorganisms and model liposome membrane
2019
The effect of methanol, ethanol, acetone, N,N-dimethylformamide (DMF), dimethyl sulfoxide and Nujol on the growth of Escherichia coli DH5α, Bacillus subtilis and Saccharomyces cerevisiae D273 was investigated. All of the tested cultures appeared susceptible to the organic media they were treated with, which evinced in apparent hindering of cell development. The observed diverse solvent tolerance, except from their different biochemical activity, may also be related to the changes in cell membrane fluidity induced by the solvent species. Parallel electron paramagnetic resonance investigations using egg yolk lecithin model liposomes revealed that the fluidity of the phospholipid system in cel…
Berries extracts as natural antioxidants in meat products: A review.
2018
The aim was to evaluate antioxidants from berries as replacement food additives for inhibition of lipid and protein oxidation in meat and meat products, since meats are highly susceptible to oxidation. Oxidation can be delayed/retarded by synthetic antioxidants with phenolic structures (e.g. butylated hydroxytoluene). However, new natural alternatives are needed for synthetic antioxidants due to the controversy regarding their possible negative health effects and consumers' demand for more ‘natural’ food additives. Berries are a good source of phenolic compounds, especially anthocyanins, which can be used as the potential alternative. Reviewed berries included bearberry (Arctostaphylos sp.)…
Endocannabinoid LTD in Accumbal D1 Neurons Mediates Reward-Seeking Behavior
2020
Summary The nucleus accumbens (NAc) plays a key role in drug-related behavior and natural reward learning. Synaptic plasticity in dopamine D1 and D2 receptor medium spiny neurons (MSNs) of the NAc and the endogenous cannabinoid (eCB) system have been implicated in reward seeking. However, the precise molecular and physiological basis of reward-seeking behavior remains unknown. We found that the specific deletion of metabotropic glutamate receptor 5 (mGluR5) in D1-expressing MSNs (D1miRmGluR5 mice) abolishes eCB-mediated long-term depression (LTD) and prevents the expression of drug (cocaine and ethanol), natural reward (saccharin), and brain-stimulation-seeking behavior. In vivo enhancement…
The Amino Acid Transporter JhI-21 Coevolves with Glutamate Receptors, Impacts NMJ Physiology, and Influences Locomotor Activity in Drosophila Larvae
2015
AbstractChanges in synaptic physiology underlie neuronal network plasticity and behavioral phenomena, which are adjusted during development. The Drosophila larval glutamatergic neuromuscular junction (NMJ) represents a powerful synaptic model to investigate factors impacting these processes. Amino acids such as glutamate have been shown to regulate Drosophila NMJ physiology by modulating the clustering of postsynaptic glutamate receptors and thereby regulating the strength of signal transmission from the motor neuron to the muscle cell. To identify amino acid transporters impacting glutmatergic signal transmission, we used Evolutionary Rate Covariation (ERC), a recently developed bioinforma…
Chlorinative stress in age-related diseases: A literature review
2017
Abstract Aging is an agglomerate of biological long-lasting processes that result being inevitable. Main actors in this scenario are both long-term inflammation and oxidative stress. It has been proved that oxidative stress induce alteration in proteins and this fact itself is critically important in the pathophysiological mechanisms leading to diseases typical of aging. Among reactive species, chlorine ones such as hypochlorous acid (HOCl) are cytotoxic oxidants produced by activated neutrophils during chronic inflammation processes. HOCl can also cause damages by reacting with biological molecules. HOCl is generated by myeloperoxidase (MPO) and augmented serum levels of MPO have been desc…
RNase H2 Loss in Murine Astrocytes Results in Cellular Defects Reminiscent of Nucleic Acid-Mediated Autoinflammation
2018
Aicardi-Goutières syndrome (AGS) is a rare early onset childhood encephalopathy caused by persistent neuroinflammation of autoimmune origin. AGS is a genetic disorder and >50% of affected individuals bear hypomorphic mutations in ribonuclease H2 (RNase H2). All available RNase H2 mouse models so far fail to mimic the prominent CNS involvement seen in AGS. To establish a mouse model recapitulating the human disease, we deleted RNase H2 specifically in the brain, the most severely affected organ in AGS. Although RNase H2δGFAPmice lacked the nuclease in astrocytes and a majority of neurons, no disease signs were apparent in these animals. We additionally confirmed these results…
Unexpected associated microalgal diversity in the lichen Ramalina farinacea is uncovered by pyrosequencing analyses
2017
The current literature reveals that the intrathalline coexistence of multiple microalgal taxa in lichens is more common than previously thought, and additional complexity is supported by the coexistence of bacteria and basidiomycete yeasts in lichen thalli. This replaces the old paradigm that lichen symbiosis occurs between a fungus and a single photobiont. The lichen Ramalina farinacea has proven to be a suitable model to study the multiplicity of microalgae in lichen thalli due to the constant coexistence of Trebouxia sp. TR9 and T. jamesii in long-distance populations. To date, studies involving phycobiont diversity within entire thalli are based on Sanger sequencing, but this method see…