The Corona Virus Disease of 2019 (COVID-19) pandemic has upset the students' daily routine, forcing them at first into a sudden transition to distance learning and then to a return to school modelled on the basis of infection containment measures. The present research involved 157 students from schools in central Italy with a mean age of 13.58 years old to investigate the affective impact of the pandemic on the school experience and its components (recess, oral testing, relationships with classmates, and relationship pupils-teachers).
View Article and Find Full Text PDFNeuronal α7 and α4β2 are the predominant nicotinic acetylcholine receptor (nAChR) subtypes found in the brain, particularly in the hippocampus. The effects of lovastatin, an inhibitor of cholesterol biosynthesis, on these two nAChRs endogenously expressed in rat hippocampal neuronal cells were evaluated in the 0.01-1 µM range.
View Article and Find Full Text PDFDiacylglycerol (DAG), a second messenger involved in different cell signaling cascades, activates protein kinase C (PKC) and D (PKD), among other kinases. The present work analyzes the effects resulting from the alteration of DAG levels on neuronal and muscle nicotinic acetylcholine receptor (AChR) distribution. We employ CHO-K1/A5 cells, expressing adult muscle-type AChR in a stable manner, and hippocampal neurons, which endogenously express various subtypes of neuronal AChR.
View Article and Find Full Text PDFThe distribution of nicotinic acetylcholine receptor (AChR) clusters at the cell membrane was studied in CHO-K1/A5 cells using fluorescence microscopy. Di-4-ANEPPDHQ, a fluorescent probe that differentiates between liquid-ordered (Lo) and liquid-disordered (Ld) phases in model membranes, was used in combination with monoclonal anti-AChR antibody labeling of live cells, which induces AChR clustering. The so-called generalized polarization (GP) of di-4-ANEPPDHQ was measured in regions of the cell-surface membrane associated with or devoid of antibody-induced AChR clusters, respectively.
View Article and Find Full Text PDFThe structural and functional properties of the nicotinic acetylcholine receptor (AChR), the archetype molecule in the superfamily of Cys-looped ligand-gated ion channels, are strongly dependent on the lipids in the vicinal microenvironment. The influence on receptor properties is mainly exerted by the AChR-vicinal ("shell" or "annular") lipids, which occur in the liquid-ordered phase as opposed to the more disordered and "fluid" bulk membrane lipids. Fluorescence studies from our laboratory have identified discrete sites for fatty acids, phospholipids, and cholesterol on the AChR protein, and electron-spin resonance spectroscopy has enabled the establishment of the stoichiometry and selectivity of the shell lipid for the AChR and the disclosure of lipid sites in the AChR transmembrane region.
View Article and Find Full Text PDFThe effects of ceramides (Cer) on the trafficking of the nicotinic acetylcholine receptor (AChR) to the plasma membrane were studied in CHO-K1/A5 cells, a clonal cell line that heterologously expresses the adult murine form of the receptor. When cells were incubated with short- (C6-Cer) or long- (brain-Cer) chain Cer at low concentrations, an increase in the number of cell-surface AChRs was observed concomitant with a decrease in intracellular receptor levels. The alteration in AChR distribution by low Cer treatment does not appear to be a general mechanism since the surface expression of the green fluorescent protein derivative of the vesicular stomatitis virus protein (VSVG-GFP) was not affected.
View Article and Find Full Text PDFThe effects of metabolic inhibition of cholesterol biosynthesis on the trafficking of the nicotinic acetylcholine receptor (AChR) to the cell membrane were studied in living CHO-K1/A5, a Chinese hamster ovary clonal line that heterologously expresses adult alpha2betadeltaepsilon mouse AChR. To this end, we submitted CHO-K1/A5 cells to long-term cholesterol deprivation, elicited by Mevinolin, a potent inhibitor of 3-hydroxy-3-methyl-glutaryl-CoA reductase and applied a combination of biochemical, pharmacological and fluorescence microscopy techniques to follow the fate of the AChR. When CHO-K1/A5 cells were grown for 48 h in lipid-deficient medium supplemented with 0.
View Article and Find Full Text PDFAnn Ist Super Sanita
February 2000
Induced abortion was legalized in Italy in 1978. After an initial increase in the incidence, from 187,631 in 1979 to 234,801 in 1983, induced abortion has steadily decreased to 140,398 in 1996. Analysis of the abortion rates has shown that the main decrease has been among married women aged 25-35, while there has been an increase among unmarried women.
View Article and Find Full Text PDFIn 1995-96 a KAP (knowledge, attitude and practice) survey on care during pregnancy, delivery and in the post-natal period was carried out in Italy by the National Institute of Health (Istituto Superiore di Sanità). A sample of 9004 women was interviewed in 13 regions within two months of the delivery. Care during pregnancy was generally at a good standard, but with an excessive use of some medical procedures.
View Article and Find Full Text PDFThe properties of the nicotinic acetylcholine receptor (AChR) are modulated by its lipid microenvironment. Studies of such modulation are hampered by the cell's homeostatic mechanisms that impede sustained modification of membrane lipid composition. We have devised a novel strategy to circumvent this problem and study the effect of changes in plasma membrane lipid composition on the functional properties of AChR.
View Article and Find Full Text PDFSustained agonist stimulation induces an asymmetric down-regulation of brain muscarinic acetylcholine receptor (mAChR): 43 +/- 2% in the right and 26 +/- 2% in the left cerebral hemisphere, respectively (Ref. 1). In order to determine the possible involvement of endogenous diacylglycerols produced under muscarinic stimulation in the down-regulation phenomenon, here we have studied the effects of synthetic diacylglycerols and a phorbol ester on cells dissociated from rat cerebral cortex.
View Article and Find Full Text PDFThe distribution and down-regulation of the muscarinic acetylcholine receptor (mAChR) were studied in dissociated cells from right (RCC) and left (LCC) cerebral cortex. For this purpose [3H]quinuclidinyl benzilate (QNB) and [3H]pirenzepine (Pz), two muscarinic antagonists, were used. The mAChR binding sites detected with [3H]QNB were asymmetrically distributed between the two hemispheres, the majority being found in the RCC.
View Article and Find Full Text PDFIn order to characterize some of the lateralized biochemical events promoted in brain upon massive neurotransmitter release, the labeling of lipids under specific stimulation of the muscarinic acetylcholine receptor (mAChR) has been studied in synaptosomes obtained from right and left cerebral cortex (RCC and LCC respectively). Synaptosomes were incubated with [32P]phosphate in the absence and in the presence of the cholinergic agonist carbamoylcholine and the muscarinic antagonist atropine. Binding of the agonist to the mAChR promoted an enhanced labeling of polyphosphoinositides, such effect being considerably more pronounced in the LCC than in the RCC.
View Article and Find Full Text PDFPhospholipid and neutral lipid composition was studied in the course of myogenic differentiation of the clonal cell line BC3H-1. Total phospholipid content increased during differentiation, predominantly in the major classes of choline and ethanolamine glycerophospholipids. The contents of other lipids, such as triacylglycerols, diminished more than 50% during this period.
View Article and Find Full Text PDFPhospholipid content and 32P-incorporation have been studied in individual rat cerebral hemispheres. The total phospholipid content was 44.9 +/- 0.
View Article and Find Full Text PDFBiochim Biophys Acta
September 1987
The level and proportion of lipids and their fatty acid composition were analyzed in highly purified transverse tubule membranes of amphibian skeletal muscle. Tubule membranes show (a) a higher content of lipids, (b) a higher phospholipid/cholesterol ratio and (c) a different phospholipid composition from other subcellular fractions, such as the light and heavy membranes from sarcoplasmic reticulum, which are similar in lipid profile. Transverse tubule membranes are characterized by a high percentage of phosphatidylserine and sphingomyelin and a low proportion of phosphatidylcholine compared with the other membranes.
View Article and Find Full Text PDFThe effects of short- and long-term ethanol administration to rats on basal levels and formation of prostacyclin (PGI2) measured as 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), and on lipid class content and fatty acid composition of isolated brain microvessels (BMV) were studied. After acute treatment (2 h, at the peak of plasma ethanol concentration) basal 6-keto-PGF1 alpha levels in BMV and release on incubation were reduced to 50% of control values. After chronic administration (15 days), PGI2 release was reduced to about 40% of control values, without changes in basal levels.
View Article and Find Full Text PDFThe effect of electroconvulsive shock on the labeling of phospholipids and neutral lipids in mice brains was examined after intracerebral injection of [1-14C] arachidonic acid or [1-14C]palmitic acid. Electroconvulsive shock reduced greatly the removal of radiolabeled arachidonic acid from the free fatty acid pool. At the same time, the incorporation of arachidonic acid was partially inhibited in triacylglycerol, diacylglycerol, and phosphatidylinositol, whereas the incorporation of [1-14C]palmitic acid was not affected.
View Article and Find Full Text PDFThe effects of acute (3 g/kg i.p. two hours before sacrifice) and chronic (6% in drinking water and libitum for 15 days) ethanol administration to male rats (200 g body weight) on basal levels and release of TxB2 and 6-keto-PGF1 alpha in brain cortex were studied.
View Article and Find Full Text PDFFree fatty acid (FFA) content was analyzed in mouse cerebral hemispheres and cerebellum under basal and postdecapitative ischemic conditions. Total FFA content immediately after decapitation (2 s) was about two-fold higher in the left hemisphere than in the right. Marked dissimilarities between hemispheres were also apparent when FFA levels were measured during short periods of ischemia.
View Article and Find Full Text PDFThe effect of postdecapitation ischemia on the labeling of the free fatty acid pool and their incorporation in lipids was examined during the first 10 min after decapitation in mouse brain that had been injected intracerebrally with either [1-14C]arachidonic acid or [1-14C]palmitic acid. One min after decapitation, animals injected with labeled arachidonic acid exhibited a greatly reduced incorporation of label in brain phospholipids, diglycerides, and triglycerides. When radioactive palmitic acid was used, brain lipids exhibited considerably less inhibition of label.
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