Effect of social isolation on oral health status - A systematic review.

AIM: To determine the magnitude of the association between social isolation and oral health in adults. MATERIALS AND METHODS: Systematic review based on PRISMA guidelines. Observational studies and clinical trials were obtained by searching the electronic databases of PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library electronic, SciELO, Science Direct and Embase. Hand searches and gray literature were included. Two researchers independently selected the studies, extracted data, and analyzed and assessed their methodological quality. The Rayyan QCRI web-based tool was used to manage and cite references, and the risk of bias was estimated according to the Cochrane Handbook for Systematic Reviews of Interventions. Meta-analysis was not performed due to insufficient data. RESULTS: The search retrieved 2545 articles. Full texts of 14 articles were read, and 1 clinical trial and 3 cross-sectional studies were included. All the studies reported on oral function, but none assessed plaque or caries parameters. The cross-sectional studies presented high risk of bias. None of the studies associated social isolation with oral health. CONCLUSIONS: There is no strong evidence for an association between social isolation and oral health in adults. Regular oral hygiene practice should be encouraged, recommended and maintained at this time of social isolation, to maintain oral health.

GUP1 and its close homologue GUP2, encoding multimembrane-spanning proteins involved in active glycerol uptake in Saccharomyces cerevisiae.

Many yeast species can utilize glycerol, both as a sole carbon source and as an osmolyte. In Saccharomyces cerevisiae, physiological studies have previously shown the presence of an active uptake system driven by electrogenic proton symport. We have used transposon mutagenesis to isolate mutants affected in the transport of glycerol into the cell. Here we present the identification of YGL084c, encoding a multimembrane-spanning protein, as being essential for proton symport of glycerol into S. cerevisiae. The gene is named GUP1 (glycerol uptake) and, for growth on glycerol, is important as a carbon and energy source. In addition, in strains deficient in glycerol production it also provides osmotic protection by the addition of glycerol. Another open reading frame (ORF), YPL189w, presenting a high degree of homology to YGL084c, similarly appears to be involved in active glycerol uptake in salt-containing glucose-based media in strains deficient in glycerol production. Analogously, this gene is named GUP2. To our knowledge, this is the first report on a gene product involved in active transport of glycerol in yeasts. Mutations with the same phenotypes occurred in two other ORFs of previously unknown function, YDL074c and YPL180w.

Contribution to the physiological characterization of glycerol active uptake in Saccharomyces cerevisiae.

Evidence is presented here that in Saccharomyces cerevisiae IGC 3507, grown either on glycerol, ethanol or acetate, glycerol is transported by a high affinity uptake system of the electrogenic proton symport type, with Km of 1.7 +/- 0.7 mM, Vmax 441 +/- 19 micromolh(-1) g(-1) dry weight and a stoichiometry of 1:1 proton per molecule of glycerol, at 30 degrees C and pH 5.0. No competitors were found among other polyols and sugars. Glycerol maximum accumulation ratios followed p.m.f. with extracellular pH. CCCP prevented glycerol accumulation, and inhibited uptake. NaCl did not interfere with H+/glycerol kinetics and energetics. This transport system was shown to be under glucose repression and inactivation. Glucose-grown cells presented, instead, a lower affinity permease for glycerol, probably a facilitated diffusion. Growth on glucose in the presence of NaCl did not induce the high affinity carrier. The stringent control of cell physiological condition over induction suggests for glycerol proton symport rather a physiological role connected with growth under gluconeogenic conditions.

Characteristics of Fps1-dependent and -independent glycerol transport in Saccharomyces cerevisiae.

Eadie-Hofstee plots of glycerol uptake in wild-type Saccharomyces cerevisiae W303-1A grown on glucose showed the presence of both saturable transport and simple diffusion, whereas an fps1delta mutant displayed only simple diffusion. Transformation of the fps1delta mutant with the glpF gene, which encodes glycerol transport in Escherichia coli, restored biphasic transport kinetics. Yeast extract-peptone-dextrose-grown wild-type cells had a higher passive diffusion constant than the fps1delta mutant, and ethanol enhanced the rate of proton diffusion to a greater extent in the wild type than in the fps1delta mutant. In addition, the lipid fraction of the fps1delta mutant contained a lower percentage of phospholipids and a higher percentage of glycolipids than that of the wild type. Fps1p, therefore, may be involved in the regulation of lipid metabolism in S. cerevisiae, affecting membrane permeability in addition to fulfilling its specific role in glycerol transport. Simultaneous uptake of glycerol and protons occurred in both glycerol- and ethanol-grown wild-type and fps1delta cells and resulted in the accumulation of glycerol at an inside-to-outside ratio of 12:1 to 15:1. Carbonyl cyanide m-chlorophenylhydrazone prevented glycerol accumulation in both strains and abolished transport in the fps1delta mutant grown on ethanol. Likewise, 2,4-dinitrophenol inhibited transport in glycerol-grown wild-type cells. These results indicate the presence of an Fps1p-dependent facilitated diffusion system in glucose-grown cells and an Fps1p-independent proton symport system in derepressed cells.

Isolation and characterisation of mutants from the halotolerant yeast Pichia sorbitophila defective in H+/glycerol symport activity.

Pichia sorbitophila, a yeast species that is highly resistant to osmotic stress in general and to salt stress in particular, was subjected to a mutagenesis strategy in order to obtain mutants deficient in the glycerol active uptake previously described. Density centrifugation was used for enrichment of NaCl sensitive mutants in either glucose or glycerol media. Several phenotypic classes of mutants were identified, to which physiological tests were applied concerning the activity of the symporter, its accumulation capacity and the detection of the activity of glycerol pathway specific enzymes. From these, two mutant strains were selected, presenting a clearly deficient phenotype on H+/glycerol symport activity.

Characterization of a glycerol/H+ symport in the halotolerant yeast Pichia sorbitophila.

Pichia sorbitophila is a halotolerant yeast capable of surviving to extracellular NaCl concentrations up to 4 M in mineral medium when glucose or glycerol are the only carbon and energy sources. Evidence is presented here that glycerol, the main compatible solute this yeast accumulates so as to maintain osmotic balance, is actively co-transported with protons. This transport system was shown to be constitutive, not needing induction by either glycerol or salt, and was not repressible by glucose. In glucose- or glycerol-grown cells, a simple diffusion was detectable, and iterative calculations were performed to calculate kinetic parameters, in the presence and in the absence of NaCl. At 25 degrees C, pH 5.0, in glucose-grown cells these were: Km = 0.81 +/- 0.11 mM and Vmax = 634.2 +/- 164.8 mumol h-1 per g (glycerol); Km = 1.28 +/- 0.60 mM and Vmax = 558.6 +/- 100.6 mumol h-1 per g (protons). Correspondent stoichiometry was approximately 1, either for these conditions or in the presence of 1 M-NaCl. An increase in accumulation capacity was evident when different concentrations of NaCl were present. This capacity was shown to be dependent on delta pH and membrane potential, consistently with an electrogenic character. We suggest that the main role of this system is in osmoregulation, by keeping glycerol accumulated inside the cells, compensating for leakage, due to its liposoluble character.

[Endocavitary fulguration of accessory pathways in the treatment of Wolff-Parkinson-White syndrome]. / Fulguração endocavitária de vias acessórias no tratamento da síndrome de Wolff-Parkinson-White.

PURPOSE: To show our first experiments with the treatment of Wolff-Parkinson-White syndrome through endocavitary fulguration of accessory pathway. PATIENTS AND METHODS: Fourteen endocavitary fulguration sessions applied in 9 patients with the Wolff-Parkinson-White syndrome. Five were men and the average age was 35 years. RESULTS: We obtained complete interruption of the conduction by the anomalous pathway in 7 cases: 4 of them needed only one session and the remaining 3, two sessions. Three fulguration sessions were carried out with the remaining patient (actually the first to be submitted to the treatment), and the procedure in that case proved to be unable to interrupt the conduction by the anomalous pathway. This patient was submitted to surgical ablation. In all cases it was not observed any cardiologic complications due to the application of this technique. CONCLUSION: The endocavitary fulguration of the accessory pathway is a safe and efficient method and must be considered as a first option when the ablation of the anomalous pathways is indicated.

[Cardiac stimulation in children. 20 years' experience]. / La stimulation cardiaque infantile. Expérience de vingt ans.

Between July, 1967 and December, 1987, 71 children and adolescents (43 boys, 28 girls) aged from 9 days to 20 years (mean 7.8 years) underwent pacemaker implantation. In 91 p. 100 of the cases this treatment was performed for complete atrioventricular block (CAVB). Surgical CAVB was the reason for 59 p. 100 of implantations (correction of tetralogy of Fallot and, more recently, of complex cardiopathies), the second main reason (16.9 p. 100) being nonsurgical CAVB associated with heart disease; the children in this group were young (mean age 4.2 years), and the prognosis mainly depended on the heart disease. Isolated congenital CAVB accounted for only 8.5 p. 100 of pacemaker implantations; these were older children (mean age 13.7 years), and the decision to implant was often difficult to reach in the absence of major functional disorders; following implantation, it was frequently found that isolated congenital CAVBs regarded as being well tolerated in fact were unrecognized handicaps. Acquired CAVB (7 p. 100) mostly consisted of Kearns' syndrome (4/5 cases). In addition, 3 children with sinus node disease and 1 with Romano-Ward syndrome benefited from cardiac pacing. Seven children died; death was in no case due to pacing but to the heart disease associated with CAVB. Endocardial pacing (68.2 p. 100 of primary implantations during the last decade) was preferred to epicardial pacing. Since 1985 we have been using exclusively screwed endocardial monopolar electrodes. The pacemakers were usually of the single-chamber ventricular type (85.9 p. 100 of primary implantations), but since 1987 dual-chamber pacemakers have been increasingly preferred for children with permanent CAVB or for replacement of pacemaker cases. Single-chamber noncompetitive ("demand") pacemakers were implanted in only 2 children: one pacemaker was connected to a ventricular electrode (atrial paralysis), the other to an atrial electrode. Whatever the type of electrode used, the pacemakers were implanted in the abdominal region in very young infants and in the pectoral region in children older than 3 or 4 years. Breakage of the wire was the main complication. Rises in threshold are the major drawback of epicardial pacing, as they require reoperation when the energy delivered cannot be effectively programmed. Endocardial pacing, preferably with a dual-chamber instrument, seems to be the best method, being the least aggressive, with minimal complications in short and very long term; it is justified as first-line treatment of permanent or predominant CAVB.(ABSTRACT TRUNCATED AT 400 WORDS)