Effect of a laser-ablated micron-scale modification of dental implant collar surface on changes in the vertical and fractal dimensions of peri-implant trabecular bone.

BACKGROUND: Marginal bone loss (MBL) represents an important indicator of peri-implant health and the measure of its level is considered a determining factor in the evaluation of the quality of survival. Aim of this study is to compare radiographic changes in the fractal and mesial/distal vertical dimensions of peri-implant trabecular bone of dental implants with a laser-ablated micron-scale modication (LAM) of collar surface after a 5-year follow-up period. MATERIALS AND METHODS: Thirty-four implants with LAM of collar surface (test group = TG) and 31 implants without LAM of collar surface (control group = CG) were placed in 45 non-smoking, periodontally healthy patients. Fractal and vertical dimensions of peri-implant trabecular bone were measured by comparing radiographs taken immediately after prosthesis delivery with those taken 3 years and 5 years after functional loading. RESULT: At the end of the 5-year follow-up, the MBL in the TG was 0.87±0.21 and 0.75±0.25 mm at the mesial and distal aspects, respectively, while a MBL of 2.05±0.25 mm at the mesial aspect and 2.01±0.34 mm at the distal site was recorded in the CG. A statistically significant difference was noted. In the TG the mean fractal dimension before loading was 1.4213±0.0525. It increased significantly to 1.4329±0.0479 at 3 years after loading and remained almost stable at 5 years after loading (1.4327±0.0291). In the CG the mean fractal dimension before loading was 1.4119±0.0414. It increased significantly to 1.4282±0.0324 at 3 years after loading and decreased significantly to 1.4111±0.0624 at 5 years after loading. At the end of the follow-up, differences between both study groups were statistically significant. CONCLUSION: The increased fractal dimension and the reduced MBL around TG implants after 5 years of functional loading indicates a positive effect of a laser-ablated micron-scale modication of collar surface on peri-implant trabecular bone remodeling.

A single high dose of dexamethasone affects the phosphorylation state of glutamate AMPA receptors in the human limbic system.

Glucocorticoids (GC) released during stress response exert feedforward effects in the whole brain, but particularly in the limbic circuits that modulates cognition, emotion and behavior. GC are the most commonly prescribed anti-inflammatory and immunosuppressant medication worldwide and pharmacological GC treatment has been paralleled by the high incidence of acute and chronic neuropsychiatric side effects, which reinforces the brain sensitivity for GC. Synapses can be bi-directionally modifiable via potentiation (long-term potentiation, LTP) or depotentiation (long-term depression, LTD) of synaptic transmission efficacy, and the phosphorylation state of Ser831 and Ser845 sites, in the GluA1 subunit of the glutamate AMPA receptors, are a critical event for these synaptic neuroplasticity events. Through a quasi-randomized controlled study, we show that a single high dexamethasone dose significantly reduces in a dose-dependent manner the levels of GluA1-Ser831 phosphorylation in the amygdala resected during surgery for temporal lobe epilepsy. This is the first report demonstrating GC effects on key markers of synaptic neuroplasticity in the human limbic system. The results contribute to understanding how GC affects the human brain under physiologic and pharmacologic conditions.

Impacted maxillary canines and root resorption of adjacent teeth: A retrospective observational study.

BACKGROUND: The prevalence of impacted maxillary canine is reported to be between 1% and 3%. The lack of monitoring and the delay in the treatment of the impacted canine can cause different complications such as: displacement of adjacent teeth, loss of vitality of neighbouring teeth, shortening of the dental arch, follicular cysts, canine ankylosis, recurrent infections, recurrent pain, internal resorption of the canine and the adjacent teeth, external resorption of the canine and the adjacent teeth, combination of these factors. An appropriate diagnosis, accurate predictive analysis and early intervention are likely to prevent such undesirable effects. The objective is to evaluate, by means of a retrospective observational study, the possibility of carrying out a predictive analysis of root resorption adjacent to the impacted canines by means of orthopantomographs, so as to limit the prescription of additional 3D radiography. MATERIAL AND METHODS: 120 subjects with unilateral or bilateral maxillary impacted canine were examined and 50 patients with 69 impacted maxillary canine (22 male, 28 female; mean age: 11.7 years) satisfied the inclusion criteria of the study. These patients were subjected to a basic clinical and radiographic investigation (orthopantomographs and computerized tomography). All panoramic films were viewed under standardized conditions for the evaluation of two main variables: maxillary canine angulations (a, b, g angles) and the overlapping between the impacted teeth and the lateral incisor (Analysis of Lindauer). Binary logistic regression was used to estimate the likelihood of resorbed lateral incisors depending on sector location and angle measurements. RESULTS: Results indicated that b angle has the greatest influence on the prediction of root resorption (predictive value of b angle = 76%). If ß angle <18° and Lindauer = I, the probability of resorption is 0.06. CONCLUSIONS: Evaluation of b angle and superimposition lateral incisor/impacted canine analysed on orthopantomographs could be one of the evaluation criteria for prescribing second level examination (CT and CTCB) and for detecting root resorption of impacted maxillary canine adjacent teeth.

Soft tissue conditions and marginal bone levels of implants with a laser-microtextured collar: a 5-year, retrospective, controlled study.

AIM: To compare clinical and radiographic outcomes of implants with a Laser-Lok®-microtextured collar to implants with a resorbable blast textured (RBT) collar after a 5-year follow-up period. MATERIALS AND METHODS: Thirty-four implants with a Laser-Lok®-microtextured collar (test group [TG]) and 31 implants with an RBT collar (control group [CG]) were placed in 45 non-smoking, periodontally healthy patients. The full-mouth plaque score, full-mouth bleeding score, number of sites with plaque, and the number of sites with bleeding on probing (BOP) were recorded at baseline, and at 1-, 2-, 3-, 4-, and 5-year follow-up. Probing depth (PD) and mucosal recession were assessed at baseline and after the 5-year follow-up period. The radiographic marginal bone loss (MBL) was calculated by subtracting the bone level at the time of crown insertion from the bone level at the 5-year follow-up. RESULTS: An implant survival rate of 94% and of 90% was reported for the TG and the CG, respectively. No statistical differences were found between the study groups for presence of plaque (10.1% vs. 25%) or for number of sites with BOP (10.3% vs. 23%). The differences between both study groups were statistically significant for mean MBL (0.81 ± 0.24 vs. 2.02 ± 0.32 mm), mean PD (2.32 ± 0.44 vs. 4.25 ± 0.87 mm), and mean mucosal recession (0.16 ± 0.3 vs. 0.22 ± 0.3 mm). CONCLUSIONS: Within the limitations of this study, results suggest that the laser-microtextured implant collar surface may provide more favorable conditions for the attachment of hard and soft tissues, and reduce the level of MBL.

Microwave-induced combustion of crude oil for further rare earth elements determination by USN-ICP-MS.

A procedure for light and heavy crude oils digestion by microwave-induced combustion (MIC) is proposed for the first time for further rare earth elements (REE) determination by inductively coupled plasma mass spectrometry (ICP-MS) equipped with an ultrasonic nebulizer (USN). Samples of crude oil (API density of 10.8-23.5, up to 250 mg) were inserted in polycarbonate capsules and combusted using 20 bar of oxygen and 50 µL of 6 mol L(-1) ammonium nitrate as igniter. Nitric acid solutions (1-14.4 mol L(-1)) were evaluated for analyte absorption and a reflux step was applied after combustion (5 min of microwave irradiation at 1400 W) in order to achieve better analyte recoveries. Accuracy was evaluated using a spiked sample and also by comparison of results obtained by microwave-assisted digestion combined to ultraviolet radiation (MW-UV) and by neutron activation analysis (NAA). Using 3 mol L(-1) HNO3, quantitative recoveries (better than 97%) were obtained for all analytes. Blank values were always negligible. Agreement was higher than 96% for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y by comparison of results with those obtained by MW-UV and by NAA (only for La, Ce, Nd, Sm, and Yb). Residual carbon content in digests using MIC was always below 1%. As an advantage over conventional procedures for crude oil digestion, using MIC, it was possible to use diluted acid as absorbing solution, obtaining better limits of detection and avoiding interferences in REE determination by USN-ICP-MS.

High-efficiency microwave-assisted digestion combined to in situ ultraviolet radiation for the determination of rare earth elements by ultrasonic nebulization ICPMS in crude oils.

A method for heavy and extraheavy crude oil digestion based on microwave-assisted wet digestion (MW-AD) and ultraviolet (UV) radiation using diluted HNO3 was applied for the determination of rare earth elements (REE) by inductively coupled plasma mass spectrometry (ICPMS) with an ultrasonic nebulizer (USN). Even using pressurized systems conventional acid digestion is not feasible for efficient crude oil digestion, especially for heavy and extraheavy crude oils that generally present high amounts of asphaltenes and resins. In the proposed system, UV radiation is generated in situ by immersed electrodeless Cd discharge lamps positioned inside quartz vessels. The use of diluted solutions (1-14.4 mol L(-1) HNO3 and 1-4 mol L(-1) H2O2) were evaluated for heavy and extraheavy crude oil digestion (API density of 11.1-19.0). With the proposed method the residual carbon content was lower than 13 mg C/100 mg of sample, and it was possible to digest sample masses up to 500 mg using 4 mol L(-1) HNO3 and 4 mol L(-1) H2O2. Interferences caused by excessive acid concentration and carbon content in digests were minimized allowing limits of quantification for REEs as low as 0.3 ng g(-1). Samples were also digested using MW-AD in pressurized systems with concentrated HNO3, but even using 280 °C, 80 bar, and concentrated HNO3, MW-AD method was not suitable for REE determination due to interferences in ICPMS determination. The combination of microwave heating with UV was considered a suitable and effective way to digest crude oil allowing further determination of low concentrations of REE by ICPMS.

Suppression of obsessive-compulsive symptoms after epilepsy surgery.

We report two male patients with medically intractable epilepsy and obsessive-compulsive disorder (OCD) symptoms. Both patients experienced remission of obsessive-compulsive symptoms after surgical treatment of epilepsy. Although the surgeries targeted different brain regions, the two patients had in common unilateral anterior cingulate cortex ablation. On the basis of these observations, we discuss the pathophysiology of OCD symptoms, emphasizing the role of corticosubcortical pathways in their genesis. Our data suggest that surgeries that affect neural loops associated with obsessive-compulsive symptoms can lead to an improvement of OCD; however, the structures responsible for this effect cannot be conclusively determined.

Cognitive performance of patients with mesial temporal lobe epilepsy and incidental calcified neurocysticercosis.

OBJECTIVES: Although chronic calcified neurocysticercosis (NCC) has been considered a major cause of symptomatic epilepsy in developing countries, it can also be an incidental pathological finding in epileptic patients from endemic regions. The mechanisms of brain plasticity occurring in patients with NCC during and after the inflammatory process related to the parasite infection, death, degeneration, and calcification within the host brain might be an independent factor for cognitive impairment in patients with NCC and epilepsy. In order to assess this possibility cognitive performance of patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) with and without NCC was investigated through structured neuropsychological testing. METHODS: Cognitive performance of long term MTLE-HS patients with (HS-NCC group, n = 32) and without NCC (HS only, n = 48) was compared. Imbalances between the two groups with respect to clinical, demographic, neuroimaging, and electrophysiological variables were adjusted by linear multiple regression analysis and Bonferroni correction for multiple tests. RESULTS AND CONCLUSIONS: There were no cognitive performance differences between HS-NCC and HS only patients, leading to the conclusion that chronic calcified NCC per se does not aggravate the cognitive performance of patients with long term MTLE-HS.

Surgical outcome in mesial temporal sclerosis correlates with prion protein gene variant.

BACKGROUND: Mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) is the most common surgically remediable epileptic syndrome. Ablation of the cellular prion protein (PrP(c)) gene (PRNP) enhances neuronal excitability of the hippocampus in vitro and sensitivity to seizure in vivo, indicating that PrP(c) might be related to epilepsy. OBJECTIVE: To evaluate the genetic contribution of PRNP to MTLE-HS. METHODS: The PRNP coding sequence of DNA from peripheral blood cells of 100 consecutive patients with surgically treated MTLE-HS was compared to that from a group of healthy controls adjusted for sex, age, and ethnicity (n = 180). The presence of PRNP variant alleles was correlated with clinical and presurgical parameters as well as surgical outcome. RESULTS: A variant allele at position 171 (Asn-->Ser), absent in controls, was found in heterozygosis (Asn171Ser) in 23% of patients (p < 0.0001). The PRNP genotypes were not correlated with any clinical or presurgical data investigated. However, patients carrying the Asn171Ser variant had a five times higher chance of continuing to have seizures after temporal lobectomy (95% CI 1.65 to 17.33, p = 0.005) than those carrying the normal allele. At 18 months after surgery, 91.8% of patients with the normal allele at codon 171 were seizure free, in comparison to 68.2% of those carrying Asn171Ser (p = 0.005). CONCLUSIONS: The PRNP variant allele Asn171Ser is highly prevalent in patients with medically untreatable MTLE-HS and influences their surgical outcome. The results suggest that the PRNP variant allele at codon 171 (Asn171Ser) is associated with epileptogenesis in MTLE-HS.

Cognitive Performance of Patients with Epilepsy and Calcified Neurocysticercotic Lesions: A Case-Control Study.

Neuropsychological tests were applied to 20 patients with focal epilepsy related to calcified neurocysticercosis (NCC) (mean: three lesions/patient; NCC group), 22 patients with focal epilepsy without NCC (EPI group), and 29 healthy controls matched for age, sex, and educational level. The EPI and NCC groups were matched for age at onset of epilepsy, epilepsy duration, frequency of attacks, seizure semiology, interictal EEG findings, and antiepileptic drugs used. There were no differences in the digit span, word span, calculus, and Mini-Mental State examination among the three groups studied. The NCC and EPI groups showed lower scores than controls in immediate and delayed verbal memory, famous faces test, spatial recognition span, abstractions and judgment, and visuoconstructional abilities. The EPI group, but not the NCC group, also had lower scores in a praxis tests. There were no differences between the NCC and EPI groups in any of the tests applied (P > 15), except for the spatial recognition span, which was lower in the former. Cognitive impairment is a prevalent neuropsychological feature of patients with epilepsy and NCC.

Atopy prevalence and spirometric performance in asymptomatic schoolchildren exposed to air pollution.

The association between respiratory disease and high levels of air pollution is well known. The most common risk factors associated with lung function decrease are air-borne particulates, ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2). The aim of our study was to evaluate any difference in the prevalence of atopy and any possible early impairment in lung function in two groups of children exposed to different levels of air pollution. We studied 220 children in two cities in northern Italy: Milan (107 children), considered a metropolitan area with a high level of air pollution, and Erba (113 children), a small town, close to Lake Como, considered a rural area with a low level of air pollution. All subjects underwent respiratory function tests and skin-prick tests for the main inhalatory allergens. Parents were requested to fill in a questionnaire about parents' smoking habits and subjective evaluation of local motor traffic intensity. Aerobiological surveys showed a significantly higher grass pollen concentration in Erba than in Milan in the study year and in the three previous years. Schoolchildren in Milan and Erba showed similar pulmonary function results, except for forced expiratory flow at 75% of forced vital capacity (FEF75) values that, while within the range of normality, were significantly lower in Milan than in Erba. A high incidence of atopy was evident in both groups: 45% among the children living in Erba and 35% among those in Milan; skin-prick-test positivity for grass-pollen was statistically more frequent in Erba than in Milan. No evidence of a link between atopy and FEF75 reduction emerged, nor between FEF75 reduction and exposure to passive smoke. The association between FEF75 reduction and chronic high levels of air pollution is appealing, but further confirmation studies are necessary.

Effect of atropine on ciliary beat in human upper respiratory tract epithelial cells.

The mucociliary apparatus is a fundamental element among the defensive mechanisms of the airways. In man, average ciliary beat frequency (CBF) has been reported to be between 600 and 1,000 beats/min and does not vary significantly at different sites along the respiratory tract. Ciliary function is altered by numerous factors, including temperature, pH, cigarette smoke, drugs, and alcohol. The aim of the present study was to evaluate whether intravenous (i.v.) infusion of atropine alters CBF. We studied nine patients (six females and three males, mean age 42.9 years) with otosclerosis, a nonrespiratory disease. All patients were scheduled for surgical stapedectomy. In all patients, nasal brushing was performed before and 20 min following i.v. injection of 0.5 mg atropine sulphate. The cellular samples, maintained viable in tissue medium, were observed under a microscope and filmed. A quantitative evaluation of ciliary activity was obtained by playing the film back in slow motion. The mean CBF value prior to atropine infusion in the nine patients studied was 588.12 (+/- 53.29 SD) beats/min. After infusion of atropine, mean CBF was 442.33 (+/- 52.82 SD) beats/min. The mean percentage drop in CBF following atropine infusion was 24.79% (t = 5.82, p < 0.001). Our data show a drop in in vitro CBF following atropine infusion which, presumably, reflects a fall in the in vivo efficacy of mucociliary transport. Atropine treatment determined a loss in CBF that was inversely correlated with increasing age.

Clinical efficacy of a vaccine-immunostimulant combination in the prevention of influenza in patients with chronic obstructive pulmonary disease and chronic asthma.

Influenza is a leading cause of morbidity and mortality in patients with chronic respiratory diseases. This study compares two influenza prevention schemes in patients with chronic obstructive pulmonary disease and chronic asthma. We enrolled 66 patients, distributed as follows: Group A: 32 subjects treated with influenza vaccine; Group B: 34 patients treated with influenza vaccine and bacterial immunostimulant. The rate of influenza episodes was recorded. Hemoagglutination inhibiting antibody titers for vaccine strains H1N1, H3N2, and B were determined at time 0 (prior to vaccination), and on days 30 and 90 following vaccination. We observed a lower rate of influenza episodes in Group B patients (8.82%) compared to Group A (31.25%) (p < 0.05). At day 90 Group B patients presented higher geometric mean antibody titers for strains H1N1 (p = 0.07) and H3N2 (p = 0.08). Bacterial immunostimulants appear as possible adjuvants in the prevention of influenza episodes, and may prolong antibody response to influenza vaccine strains.

Congenital bronchobiliary fistula: first case in an adult.

The first adult case of a congenital communication between the biliary tract and the right main bronchus is reported. Treatment by surgical excision and pneumonectomy was successful.

Effects of exogenous gangliosides on the pattern of respiratory enzymes in experimental diabetic retino-pathy in the rat.

The prevalence of LDH1 in the retina let us think that this tissue, in normal conditions, is particularly resistant to anoxia; yet the datum relative to the variations, of LDH1 pattern in the degenerating retina with decrease of LDH1, makes more probable the hypothesis of a variable sensitivity of the enzyme in the normal metabolic conditions. This consideration, which can also be extended to the other enzymatic systems, justifies our research line.