1,457 research outputs found
Band structure and atomic sum rules for x-ray dichroism
Corrections to the atomic orbital sum rule for circular magnetic x-ray
dichroism in solids are derived using orthonormal LMTOs as a single-particle
basis for electron band states.Comment: 7 pages, no figure
Primordial and primary prevention of peri-implant diseases: A systematic review and meta-analysis
Aim: This systematic review and meta-analysis aims to assess the efficacy of risk factor control to prevent the occurrence of peri-implant diseases (PIDs) in adult patients awaiting dental implant rehabilitation (primordial prevention) or in patients with dental implants surrounded by healthy peri-implant tissues (primary prevention). Materials and Methods: A literature search was performed without any time limit on different databases up to August 2022. Interventional and observational studies with at least 6 months of follow-up were considered. The occurrence of peri-implant mucositis and/or peri-implantitis was the primary outcome. Pooled data analyses were performed using random effect models according to the type of risk factor and outcome. Results: Overall, 48 studies were selected. None assessed the efficacy of primordial preventive interventions for PIDs. Indirect evidence on the primary prevention of PID indicated that diabetic patients with dental implants and good glycaemic control have a significantly lower risk of peri-implantitis (odds ratio [OR] = 0.16; 95% confidence interval [CI]: 0.03–0.96; I2: 0%), and lower marginal bone level (MBL) changes (OR = –0.36 mm; 95% CI: −0.65 to −0.07; I2: 95%) compared to diabetic patients with poor glycaemic control. Patients attending supportive periodontal/peri-implant care (SPC) regularly have a lower risk of overall PIDs (OR = 0.42; 95% CI: 0.24–0.75; I2: 57%) and peri-implantitis compared to irregular attendees. The risk of dental implant failure (OR = 3.76; 95% CI: 1.50–9.45; I2: 0%) appears to be greater under irregular or no SPC than regular SPC. Implants sites with augmented peri-implant keratinized mucosa (PIKM) show lower peri-implant inflammation (SMD = –1.18; 95% CI: −1.85 to −0.51; I2: 69%) and lower MBL changes (MD = –0.25; 95% CI: −0.45 to −0.05; I2: 62%) compared to dental implants with PIKM deficiency. Studies on smoking cessation and oral hygiene behaviors were inconclusive. Conclusions: Within the limitations of available evidence, the present findings indicate that in patients with diabetes, glycaemic control should be promoted to avoid peri-implantitis development. The primary prevention of peri-implantitis should involve regular SPC. PIKM augmentation procedures, where a PIKM deficiency exists, may favour the control of peri-implant inflammation and the stability of MBL. Further studies are needed to assess the impact of smoking cessation and oral hygiene behaviours, as well as the implementation of standardized primordial and primary prevention protocols for PIDs
Effectiveness of implant-supported fixed partial denture in patients with history of periodontitis: A systematic review and meta-analysis
Aim: This systematic review investigates the effectiveness of implant-supported fixed partial denture (IS-FPD) in patients with history of periodontitis (HP) vs. patients with no history of periodontitis (NHP). Methods: A literature search was performed on different databases on May 2020. Prospective and retrospective studies assessing survival (primary outcome), success and biological/mechanical complications of IS-FPDs in HP vs. NHP patients at ≥1 year after implant loading were evaluated. Meta-analyses were conducted by estimating hazard ratio (HR), risk ratio (RR) and standardized mean differences (SMD) with 95% confidence intervals (CI) using random effect models. Results: Of the initially identified 4096 articles, 349 underwent a full-text evaluation. Finally, 17 were included. Pooled data analyses showed that overall implant survival was significantly higher in the NHP than the HP group (HR = 2.06; 95% CI = 1.37–3.09; I2 = 0%). This difference was noted when follow-up ≥5 years. The risk of peri-implantitis was higher in HP than NHP patients (RR = 3.3; 95% CI = 1.31–8.3; I2 = 0%), whereas the mean marginal bone level change over time was not different between the groups (SMD = −0.16 mm; 95% CI = −1.04–0.73; I2 = 98%). Conclusions: In partially edentulous patients receiving IS-FPDs, a history of periodontitis is associated with poorer survival rate and higher risk of peri-implantitis during a 5–10 years period after implant loading
Verifying synonymies between grape cultivars from France and Northwestern Italy using molecular markers
Thirty-one grape cultivars from France and Northwestern Italy, presumed to be synonymous, were analyzed using RAPD (Random Amplified Polymorphic DNA) and SSR (Simple Sequence Repeats or microsatellite) markers to verify 25 synonym hypotheses. RAPD analyses were performed with 8 selected decamer primers and the profiles of 7 microsatellite loci were used in order to confirm RAPD results, if required. Sixteen synonymies were confirmed, including the French cv. Verdesse with the Italian cv. Bian ver, the French cv. Persan with the Italian cv. Biquet, the French cv. Chatus with the Italian cv. Neiret, the French cv. Gouais blanc with the Italian cvs Preveiral and Liseiret. Most of the investigated cultivars belong to the Vitis vinifera germplasm of both sides of the Western Alps and the occurrence of synonyms indicates the existence of a common pool of grapes grown under different names in this part of Europe.
Shared detection of Porphyromonas gingivalis in cohabiting family members: a systematic review and meta-analysis
Introduction: Periodontitis is an inflammatory dysbiotic disease. Among putative dysbiosis causes, transmission of Porphyromonas gingivalis between individuals of the same family remains unclear. The aim of this systematic review and meta-analysis is to assess the likelihood of shared detection of Porphyromonas gingivalis among cohabiting family members. Methods: A literature search?was conducted on different databases up to September 2018. Articles assessing the presence of P.gingivalis between members of the same family were screened. Only English literature was retrieved, whereas no limits were applied for bacterial sampling and detection methods. Results: Overall, 26 articles published between 1993 and 2017 met the inclusion criteria. Of these, 18 articles were used for meta-analyses. Based on bacterial culture, the likelihood of an intra-familial transmission of P.gingivalis once a member of the family harbors the bacterium is estimated at 63.5% (n = 132 pairs of family members); this drops to 45% when pooling together culture and Polymerase-Chain-Reaction (n = 481 pairs), whereas it is estimated at 35.7% when genotyping is applied (n = 137 pairs). Conclusion: Pooled results suggest that the likelihood of detecting P.gingivalis within within family members is moderately frequent. Personalized periodontal screening and prevention may consider intra-familial co-occurrence of P.gingivalis as feasible
Promoting behavioural changes to improve oral hygiene in patients with periodontal diseases: a systematic review
Aim: This systematic review investigates the impact of specific interventions aiming at promoting behavioural changes to improve oral hygiene (OH) in patients with periodontal diseases. Methods: A literature search was performed on different databases up to March 2019. Randomized and non-randomized controlled trials evaluating the effects of behavioural interventions on plaque and bleeding scores in patients with gingivitis or periodontitis were considered. Pooled data analysis was conducted by estimating standardized mean difference between groups. Results: Of 288 articles screened, 14 were included as follows: 4 studies evaluated the effect of motivational interviewing (MI) associated with OH instructions, 7 the impact of oral health educational programmes based on cognitive behavioural therapies, and 3 the use of self-inspections/videotapes. Studies were heterogeneous and reported contrasting results. Meta-analyses for psychological interventions showed no significant group difference for both plaque and bleeding scores. No effect was observed in studies applying self-inspection/videotapes. Conclusions: Within the limitations of the current evidence, OH may be reinforced in patients with periodontal diseases by psychological interventions based on cognitive constructs and MI principles provided by oral health professionals. However, no conclusion can be drawn on their specific clinical efficacy as measured by reduction of plaque and bleeding scores over time
Impact of risk factor control interventions for smoking cessation and promotion of healthy lifestyles in patients with periodontitis: a systematic review
Aim: The aim of this systematic review was to identify the most recent widely accepted guidelines for risk factor control interventions and to assess their impact in patients with periodontitis. Materials and methods: The electronic search strategy included a first systematic search to identify guidelines for interventions for smoking cessation, diabetes control, physical exercise (activity), change of diet, carbohydrate (dietary sugar) reduction and weight loss in the general population and a second systematic search to identify the studies evaluating these interventions in periodontitis patients. Results: A total of 13 guidelines and 25 studies were selected. Most guidelines included recommendations for all healthcare providers to provide interventions and follow-up counselling with the risk factors considered in the present review. In patients with periodontitis, interventions for smoking cessation and diabetes control were shown to improve periodontal health while the impact of dietary interventions and the promotion of other healthy lifestyles were moderate or limited. Conclusions: While aiming to improve treatment outcomes and the maintenance of periodontal health, current evidence suggests that interventions for smoking cessation and diabetes control are effective, thus emphasizing the need of behavioural support in periodontal care
Clearance of the mutant androgen receptor in motoneuronal models of spinal and bulbar muscular atrophy.
Spinal and bulbar muscular atrophy (SBMA) is an X-linked motoneuron disease caused by an abnormal expansion of a tandem CAG repeat in exon 1 of the androgen receptor (AR) gene that results in an abnormally long polyglutamine tract (polyQ) in the AR protein. As a result, the mutant AR (ARpolyQ) misfolds, forming cytoplasmic and nuclear aggregates in the affected neurons. Neurotoxicity only appears to be associated with the formation of nuclear aggregates. Thus, improved ARpolyQ cytoplasmic clearance, which indirectly decreases ARpolyQ nuclear accumulation, has beneficial effects on affected motoneurons. In addition, increased ARpolyQ clearance contributes to maintenance of motoneuron proteostasis and viability, preventing the blockage of the proteasome and autophagy pathways that might play a role in the neuropathy in SBMA. The expression of heat shock protein B8 (HspB8), a member of the small heat shock protein family, is highly induced in surviving motoneurons of patients affected by motoneuron diseases, where it seems to participate in the stress response aimed at cell protection. We report here that HspB8 facilitates the autophagic removal of misfolded aggregating species of ARpolyQ. In addition, though HspB8 does not influence p62 and LC3 (two key autophagic molecules) expression, it does prevent p62 bodies formation, and restores the normal autophagic flux in these cells. Interestingly, trehalose, a well-known autophagy stimulator, induces HspB8 expression, suggesting that HspB8 might act as one of the molecular mediators of the proautophagic activity of trehalose. Collectively, these data support the hypothesis that treatments aimed at restoring a normal autophagic flux that result in the more efficient clearance of mutant ARpolyQ might produce beneficial effects in SBMA patients
Effect of atmospheric nitric oxide (NO) on measurements of exhaled NO in asthmatic children
The measurement of exhaled nitric oxide concentrations [NO] may provide a simple, noninvasive means for measuring airway inflammation. However, several measurement conditions may influence exhaled NO levels, and ambient NO may be one of these. We measured exhaled NO levels in 47 stable asthmatic children age 5 to 17 years and in 47 healthy children, gender and age matched. Exhaled [NO] in expired air was measured by a tidal breathing method with a chemiluminescence analyzer, sampling at the expiratory side of the mouthpiece. NO steady\u2010state levels were recorded. In order to keep the soft palate closed and avoid nasal contamination, the breathing circuit had a restrictor providing an expiratory pressure of 3\u20134 cm H2O at the mouthpiece. To evaluate the effect of [NO] in ambient air, measurements were randomly performed by breathing ambient air or NO\u2010free air from a closed circuit. Breathing NO\u2010free air, exhaled [NO] in asthmatics (mean \ub1 SEM) was 23.7 \ub1 1.4 ppb, significantly higher (P < 0.001) than in healthy controls (8.7 \ub1 0.4 ppb). Exhaled NO concentrations measured during ambient air breathing were higher (49 \ub1 4.6 ppb, P < 0.001) than when breathing NO\u2010free air (23.7 \ub1 1.4 ppb) and were significantly correlated (r = 0.89, P < 0.001) with atmospheric concentrations of NO (range 3\u2013430 ppb). These findings show that (1) exhaled [NO] values of asthmatic children are significantly higher than in healthy controls, and (2) atmospheric NO levels critically influence the measurement of exhaled [NO]. Therefore, using a tidal breathing method the inhalation of NO\u2010free air during the test is recommended. Pediatr Pulmonol. 1998; 26:30\u201334. \ua9 1998 Wiley\u2010Liss, Inc
- …