Development and calibration of a new mathematical model for the description of an ion-exchange process for ammonia removal in the presence of competing ions.

Ammonia ion removal and recovery via an ion-exchange process using zeolites is a promising alternative to traditional biological treatments. The analysis of its efficiency is not straightforward as it depends on various factors, such as the cation exchange capacity of the zeolite, amount of zeolite available, initial ammonia concentration, contact time, ammonia speciation depending on pH or the presence of competing ions. Mathematical modelling and simulation tools are very useful to analyse the effect of different operational conditions on the efficiency and optimal operation of the process. This paper experimentally analyses the effect that the presence of competing ions has on the efficiency of ammonia removal. This experimental work has shown a reduction of around 21% of ammonia removal efficiency in the presence of competing ions. The main contribution of this paper is the development new mathematical model able to describe the ion-exchange process in the presence of competing ions. The mathematical model developed is able to analyse the performance of the IEX process under different empty bed contact times, influent loads, pH and concentrations of competing ions. The capability of the model to reproduce real data has been proven comparing the experimental and simulation results. Finally, an exploration by simulation has been undertaken to show the potential of the mathematical model developed.

Xenograft materials in maxillary sinus floor elevation surgery: a systematic review with network meta-analyses.

A systematic review and network meta-analysis was conducted to compare different commercially available xenograft materials used in maxillary sinus floor elevation surgery (MSFES). Embase, PubMed, the Cochrane Library, Web of Science, Scopus, LILACS, and grey literature were searched up to 13 July 2020. Only randomised controlled trials (RCTs) were included. A frequentist network meta-analysis using a random effects model compared different commercially available xenograft materials. The primary outcomes were the percentage of newly-formed bone and residual bone-substitute rate. Both were measured by histomorphometric analysis from bone biopsies obtained during preparation of the implant site. Of the 659 studies initially identified, 11 involving 242 MSFES were included in the quantitative analyses. A total of six bone-substitute materials were analysed (Bio-Oss® (Geistlich Pharma), InduCera® Dual Coat, Lumina-Bone Porous® (Critéria), Osseous® (SIN - Sistema de Implantes Nacional), THE Graft® (Purgo Biologics), and Osteoplant Osteoxenon® (Bioteck)). The P-score estimation showed that Osteoplant Osteoxenon® produced the most newly-formed bone and reabsorbed faster than other xenograft materials after six months. The combination of Bio-Oss® plus bone marrow aspirate concentrate (BMAC) significantly increased the percentage of newly-formed bone compared with Bio-Oss® alone. In contrast, the addition of Emdogain® (Straumann) and leucocyte and platelet-rich fibrin (L-PRF) to Bio-Oss® did not significantly improve the amount of regenerated bone. Study-level data indicated that the percentage of newly-formed bone differs among commercially available xenograft materials. Osteoplant Osteoxenon® seems to result in the highest amount of new bone in MSFES.

Histomorphometric evaluation of different grafting materials used for alveolar ridge preservation: a systematic review and network meta-analysis.

In this systematic review and network meta-analysis including only randomized clinical trials (RCTs), different grafting materials used in alveolar ridge preservation after tooth extraction were analysed, focusing on histomorphometric new bone formation (NBF) in core biopsies obtained during implant placement. The PubMed, Embase, Cochrane Library, Web of Science, Scopus, and LILACS databases, as well as the grey literature, were searched for published and unpublished trials (from database inception to January 14, 2019). The primary outcome was the percentage of NBF. The secondary outcomes were the percentage of residual biomaterial and the percentage of soft tissue. An arm-based network meta-analysis was performed. The rank of intervention efficacy was obtained to measure the probability of each biomaterial being ranked first across all interventions. A total of 1526 studies were found, of which 38 were included for quantitative analysis. Three trials were rated as having a high risk of bias and 35 trials as having an unclear risk of bias. The network meta-analysis showed that nine grafting materials decreased NBF and 25 did not decrease NBF. The grafting material with the highest amount of NBF was plasma rich in growth factors. Due to the lack of studies with a low risk of bias, further RCTs are needed for definitive conclusions.

Randomized double-blind clinical trial evaluation of bone healing after third molar surgery with the use of leukocyte- and platelet-rich fibrin.

The objective of this study was to evaluate the use of leukocyte- and platelet-rich fibrin (L-PRF) in bone healing after mandibular third molar extraction. In this prospective, double-blind, split-mouth study, 34 extractions were performed. On one side, the socket was sutured primarily (control side); on the other side, L-PRF was inserted before suturing. The patients were assessed for postoperative bone regeneration, pain and soft tissue healing. The primary outcome was bone regeneration, which was performed through tomographic evaluation in the immediate postoperative period and 3 months after the procedure. The ITK-SNAP software was used for image evaluation by the intensity of grey of each voxel. Pain was analysed using a visual analogue scale (VAS), and soft tissue healing was analysed both based on the modified healing index of Landry et al., and by comparing pre- and postoperative periodontal probing at the distal of the lower second molar. The application of L-PRF improved bone density, which was higher in test group (p=0.007). There was no statistical difference related to pain or soft tissue between the groups (p>0.05). There was evidence for improved bone healing in response to L-PRF. However, to better understand the effect of L-PRF more clinical trials with larger samples are necessary.

Platelet-rich fibrin in oral surgical procedures: a systematic review and meta-analysis.

The effect of platelet-rich fibrin (PRF) in enhancing the healing after oral surgical interventions is still a matter of debate. The purpose of this study was to identify instances where PRF has been shown to be effective in oral surgical procedures. A comprehensive literature search was performed up to 2017 on PubMed/MEDLINE, Cochrane Library, Web of Science, Scopus and LILACS databases and grey literature. The full-text of potentially relevant studies were reviewed and only randomized clinical trials (RCTs) were included. A total of 559 studies were found, of which 30 were included for qualitative analysis and 13 for quantitative analysis. Three review authors assessed the risk of bias independently. The available literature suggests that PRF has a positive effect in improving alveolar preservation on extraction sockets and around dental implants. The qualitative analysis showed a significantly better effect of PRF in promoting bone regeneration for alveolar cleft reconstruction. The meta-analysis for third molar surgery showed a decrease in prevalence of alveolar osteitis. PRF increased implant stability 1 week and 1 month after surgery (P=0.0005 and 0.0003). Due to the lack of studies with low risk of bias and a limited number of patients available, further RCTs are needed to confirm these results.

Comparison of the accuracy of maxillary position between conventional model surgery and virtual surgical planning.

The aim of this study was to determine whether virtual surgical planning (VSP) is an accurate method for positioning the maxilla when compared to conventional articulator model surgery (CMS), through the superimposition of computed tomography (CT) images. This retrospective study included the records of 30 adult patients submitted to bimaxillary orthognathic surgery. Two groups were created according to the treatment planning performed: CMS and VSP. The treatment planning protocol was the same for all patients. Pre- and postoperative CT images were superimposed and the linear distances between upper jaw reference points were measured. Measurements were then compared to the treatment planning, and the difference in accuracy between CMS and VSP was determined using the t-test for independent samples. The success criterion adopted was a mean linear difference of <2mm. The mean linear difference between planned and obtained movements for CMS was 1.27±1.05mm, and for VSP was 1.20±1.08mm. With CMS, 80% of overlapping reference points had a difference of <2mm, while for VSP this value was 83.6%. There was no statistically significant difference between the two techniques regarding accuracy (P>0.05).

Evaluation of postoperative complications after mandibular third molar surgery with the use of platelet-rich fibrin: a systematic review and meta-analysis.

The current literature was reviewed to analyze the effects of platelet-rich fibrin (PRF) on postoperative complications after mandibular third molar surgery (pain, alveolar osteitis, swelling, and bone healing). A comprehensive literature search was performed up to 2016 in the PubMed/MEDLINE, Cochrane Library, LILACS, and ScienceDirect databases and the grey literature. Additional records were identified through manual and reference searches. The full-text articles of potentially relevant studies were reviewed; only randomized clinical trials were included. Two review authors assessed the risk of bias independently. A total of 1430 publications were evaluated, of which seven were selected for qualitative analysis and two for quantitative analysis. A meta-analysis was performed only for alveolar osteitis, due to the considerable heterogeneity among studies for the other outcome variables. There were 485 extractions (243 test, 242 control) in 280 patients. PRF appeared to accelerate healing in mandibular third molar surgery, reducing postoperative pain and swelling. Quantitative analysis showed a decrease in prevalence of alveolar osteitis (odds ratio 0.31, 95% confidence interval 0.13-0.77, Z=2.54, P=0.01). Although more clinical trials of a better design and with larger samples are necessary to allow definitive conclusions to be drawn, PRF is a potentially useful biomaterial.

Effects of surgical correction of class III malocclusion on the pharyngeal airway and its influence on sleep apnoea.

The objective of this study was to evaluate, through cone beam computed tomography, the immediate changes in pharyngeal airway space (PAS) after orthognathic surgery in class III patients, and to determine the influence of surgery on the development of obstructive sleep apnoea hypopnoea syndrome (OSAHS). A prospective study was conducted; 33 patients were divided into three groups: mandibular setback surgery (nine patients), bimaxillary surgery (18 patients), and maxillary advancement surgery (six patients). PAS measurements obtained pre- and postoperatively were compared using the t-test. All patients were assessed clinically for OSAHS before surgery and at 6 months postoperative using the Berlin questionnaire and a combined clinical assessment, which included the assessment of OSAHS symptoms, Epworth Sleepiness Scale score, and body mass index. Patients undergoing isolated mandibular setback surgery demonstrated a decrease in total PAS volume, in hypopharynx volume, and in minimum cross-sectional area of the pharynx immediately after surgery (P<0.05). The clinical analysis did not reveal signs or symptoms of OSAHS in any of the 33 patients. Although patients who underwent mandibular setback surgery alone demonstrated a volume reduction in the PAS and a decrease in minimum cross-sectional area, these reductions were not accompanied by signs or symptoms of OSAHS.

The use of anatomical models for learning anesthesia techniques in oral surgery.

AIM: The objective of this work is to present a new collaborative method for teaching administration of anesthetic block in dentistry, with three-dimensional anatomical models used to improve learning and thereby increase safety, reduce anxiety, and improve the performance of students during the administration of anesthesia in the patients. MATERIALS AND METHODS: Three-dimensional (3D) models of skulls were made that reproduced all innervations of the V th cranial nerve (trigeminal nerve), as well as some blood vessels, glands, and muscles of mastication. For teaching the local anesthetic techniques we prepared pictures and videos of the administration of anesthesia in the models , which were presented to 130 students in two universities in Brazil. With the help of the models the students could follow the path of the nerves to be anesthetized and identify the anatomical points of reference for the correct positioning of the needle in the tissues. After the presentation the students answered a questionnaire aiming to assess the effect of the 3D models on learning. RESULTS: Eighty-eight percent of students rated the material as excellent, 12% as good, 0% as regular, and 0% as bad (unnecessary materials). After the presentation, 70% of the students felt confident about being able to achieve the nerve block in patients. CONCLUSION: When exposed to an appropriate method, students recognized the importance of knowledge of anatomy for learning local anesthetic techniques. This method improved the quality of education and increased patient safety during the first injection.

Treatment of severe facial asymmetry secondary to osteochondroma of the mandibular condyle: case report.

Osteochondroma (OC) is the most common benign tumor of long bones. However it is rarely found in the facial skeleton, being the coronoid process and mandibular condyle the most affected sites in this region. It basically consists in bone growth covered by cartilage. The etiology is still controversial: neoplastic, developmental, reparative and traumatic origins have been discussed in literature. The treatments of these lesions include total condylectomy or local resection of the lesion. This paper aims to report a case of a patient with history of trauma and possible fracture of the mandibular condyle in childhood, which in youth developed dentofacial deformity with severe facial asymmetry. The treatment consisted of resection of lesion both with maxillary and mandibular osteotomies associated with graft from the iliac crest bone. Actually, the patient is with a favorable aesthetic, without functional deficit and absence of lesion's recurrence.

[Sugammadex, efficacious in reversing a neuromuscular block in a woman with Becker muscular dystrophy]. / Eficacia de sugammadex para la reversión del bloqueo neuromuscular en una paciente con distrofia muscular de Becker.

Becker muscular dystrophy affects mainly the musculoskeletal system, causing muscle wasting and progressive weakness. A 61-year-old woman with breast cancer, who had been diagnosed with Becker muscular dystrophy 45 years earlier, was scheduled for right mastectomy. We induced general anesthesia with propofol, fentanyl, and a nondepolarizing muscle blocker (rocuronium). Neuromuscular function was monitored continuously by acceleromyographic train-of-four ratio (TOFr) (Watch-SX monitor). The block was reversed with sugammadex. After preoxygenation with fentanyl and propofol, the device was calibrated and the baseline TOFr was recorded. We injected 1 mg/kg of rocuronium and assessed TOF responses every 15 seconds. The maximum decrease in TOF response (to 0 twitches) was at 52 seconds. Tracheal intubation was uneventful. Anesthesia was maintained by intravenous infusion. The operation lasted 74 minutes. The second TOF twitch (T2) reappeared 86 minutes after the initial dose. After we injected 2 mg/kg of sugammadex, a TOFr of 0.7 was reached at 79 seconds; a TOFr of 0.9 was reached at 108 seconds and a TOFr of 1.0 at 152 seconds. No electrocardiographic or hemodynamic abnormalities occurred during sugammadex administration and there were no signs of residual neuromuscular blockade on awakening or adverse events in the following 24 hours.

Case-finding of pulmonary tuberculosis on admission to a penitentiary centre.

SETTING: The prison population is considered to be at high risk of tuberculosis infection and illness. Therefore, a tuberculosis prevention and control program was put into effect upon the opening of a penitentiary center in Barcelona whose inmates suffered a high prevalence of intravenous drug use (IVDU) (48.4%) and HIV-1 infection (36.0%). OBJECTIVE: To ascertain the prevalence of tuberculosis infection and pulmonary tuberculosis detected on admission to jail among those prisoners who had no history of tuberculosis; and to study as predictors of tuberculosis infection and illness the variables age, IVDU and HIV-1 infection. DESIGN: Cross-sectional study. RESULTS: Of the 729 prisoners studied, 56.2% were considered infected with Mycobacterium tuberculosis. Age was the only variable associated with the infection, with an Odds Ratio (OR) of 1.017 per year (Confidence Interval [CI] 95% = 1.006-1.029) (P = 0.004). The rates of HIV-1 and M. tuberculosis co-infection, which may run between 18.9% and 21.7%, reached 42.8% in the IVDU. A 2.7% prevalence of pulmonary tuberculosis was observed. The most accurate logistic regression model for pulmonary tuberculosis diagnosis (P = 0.09) includes the variables tuberculosis infection (OR = 13.00; CI 95% = 1.7-98), IVDU (OR = 2.60; CI 95% = 0.66-7.81) and age (OR = 1.05; CI 95% = 0.99-1.11). CONCLUSION: Given the high prevalences observed, we propose the activation and maintenance of programs designed to seek out and identify cases of M. tuberculosis infection and illness within the prison population.

Semiautomatic quantification of silver-stained nucleolar organizer regions in tissue sections and cellular smears.

Silver staining of nucleoli reveals argyrophilic proteins associated with nucleolar organizer region (Ag-NOR) proteins. Argyrophilic components appear as dots about 1 micron in diameter dispersed throughout the nucleolus (Ag-NOR dots). The count of Ag-NOR dots is a useful index for improving the cancer diagnosis and determination of prognosis. Here we describe software developed on a medium-cost image analyzer in order to evaluate the mean area of NORs and their number relative to an internal reference, the number and areas of clusters of NORs and the area of the nucleus. Statistical analysis of the data was performed during counting. The first application concerned counting NOR dots during mitosis in cell imprints; those counts were 2.3, 15.3 and 55.56 for the metaphase, telophase and interphase, respectively (relative to unitary dots of metaphase cells). In the second application we demonstrated a significant difference in NOR numbers between two groups of prostatic cancers with good and poor prognoses (6.05 +/- 2.79 SD and 7.96 +/- 3.01, respectively; with Student's t test, = 1.999; P = .05).

[Effect of water containing calcium and magnesium sulfates on the elimination of cholesterol in the rat]. / Rôle d'une eau sulfatée calcique et magnésienne sur l'élimination du cholestérol chez le rat.

In the rat, the activity of the thermal water of Capvern and of its ionic components on the modification of the flow rate and composition of hepatic bile has been investigated. Two groups of rats were selected: the first group received per os an overload of the thermal water during six weeks. At that time on empty stomach a great increase of biliary phospholipids was observed. An intraduodenal injection of the thermal water produced a significant and rapid increase of biliary flow rate and biliary cholesterol. the animals of the second group received through intraduodenal injections the thermal water or an anionic solution composed of calcium, of magnesium sulphate or of both salts at their concentration in the thermal water, respectively. We observed an increase in biliary flow rate and biliary calcium concentration in the rats receiving the solution of calcium sulphate only and an increase of choleresis in the rats receiving the thermal water only. These data suggest that the thermal water has a specific action on the metabolism of cholesterol in increasing its biliary elimination particularly through the calcium ion content of the water.

[Influence of calcic and magnesic sulphurous thermal water on the metabolism of lipoproteins in the rat]. / Influence d'une eau thermale sulfatée calcique magnésienne sur le métabolisme des lipoprotéines chez le rat.

We have studied in rats fed hypercholesterolemic diet the action of calcic and magnesic sulphurous water from Capvern on the modification of the lipoproteins metabolism caused by hypercholesterolemia. The rats subjected to a hypercholesterolemic diet with thermal water of Capvern was found to have a plasma level of cholesterol significantly less increased (P less than 0.01) compared to those subjected to the same diet with ordinary drinking water (25%). We demonstrated after 105 days of experimentation on tested rats that thermal water may affect the cholesterol catabolism by increased level of cholesterol HDL (52%) and stabilizing level of cholesterol LDL comparatively to the controls. These data suggest that the thermal water from Capvern enhanced the transformation of cholesterol to biliary acids and their biliary secretion. A possible relationship between the influence of the thermal water and the metabolism of lipoproteins would be explained by a possible increase of hepatic receptors which identify apolipoproteins B (LDL) and E (HDLc) on cholesterol fed rats, suggesting a great synthesis of nascent apolipoproteins HDL which are antiatherogenic.

A chemical study of the protein fraction of Mediterranean sweet almond varieties (Prunus amygdalus).

The protein contents and amino-acid compositions of five Mediterranean almond varieties were determined. The protein contents were between 18 and 24 g/100 g of almond, according to variety. The content of each amino-acid, expressed in g/100 g of protein, was similar in all varieties. The essential amino-acid composition was compared with the FAO pattern of amino-acid requirements and to the protein of milk and eggs. Percentages of albumins, globulins, glutelins and prolamines were also determined.