Using single-species and algal communities to determine long-term adverse effects of silver nanoparticles on freshwater phytoplankton

The physical and chemical properties of silver nanoparticles (AgNPs) have led to their increasing use in various fields such as medicine, food, and industry. Evidence has proven that AgNPs cause adverse effects in aquatic ecosystems, especially when the release of Ag is prolonged in time. Several studies have shown short-term adverse effects of AgNPs on freshwater phytoplankton, but few studies have analysed the impact of long-term exposures on these populations. Our studies were carried out to assess the effects of AgNPs on growth rate, photosynthesis activity, and reactive oxygen species (ROS) generation on the freshwater green algae Scenedesmus armatus and the cyanobacteria Microcystis aeruginosa, and additionally on microcystin (MC-LR) generation from these cyanobacteria. The tests were conducted both in single-species cultures and in phytoplanktonic communities exposed to 1 ngL-1 AgNPs for 28 days. The results showed that cell growth rate of both single-species cultures decreased significantly at the beginning and progressively reached control-like values at 28 days post-exposure. This effect was similar for the community-cultured cyanobacteria, but not for the green algae, which maintained a sustained decrease in growth rate. While gross photosynthesis (Pg) increased in both strains exposed in single cultures, dark respiration (R) and net photosynthesis (Pn) decreased in S. armatus and M. aeruginosa, respectively. These effects were mitigated when both strains were exposed under community culture conditions. Similarly, the ROS generation shown by both strains exposed in single-species cultures was mitigated when exposure occurred in community cultures. MC-LR production and release were significantly decreased in both single-species and community exposures. These results can supply helpful information to further investigate the potential risks of AgNPs and ultimately help policymakers make better-informed decisions about their utilization for environmental restoration.

Tuberculosis in Spain: An opinion paper

This document is the result of the deliberations of the Committee on Emerging Pathogens and COVID-19 of the Illustrious Official College of Physicians of Madrid (ICOMEM) regarding the current situation of tuberculosis, particularly in Spain. We have reviewed aspects such as the evolution of its incidence, the populations currently most exposed and the health care circuits for the care of these patients in Spain. We have also discussed latent tuberculosis, the reality of extrapulmonary disease in the XXI century and the means available in daily practice for the diagnosis of both latent and active forms. The contribution of molecular biology, which has changed the perspective of this disease, was another topic of discussion. The paper tries to put into perspective both the classical drugs and their resistance figures and the availability and indications of the new ones. In addition, the reality of direct observation in the administration of antituberculosis drugs has been discussed. All this revolution is making it possible to shorten the treatment time for tuberculosis, a subject that has also been reviewed. If everything is done well, the risk of relapse of tuberculosis is small but it exists. On the other hand, many special situations have been discussed in this paper, such as tuberculosis in pediatric age and tuberculosis as a cause for concern in surgery and intensive care. The status of the BCG vaccine and its present indications as well as the future of new vaccines to achieve the old dream of eradicating this disease have been discussed. Finally, the ethical and medicolegal implications of this disease are not a minor issue and our situation in this regard has been reviewed.

Adverse effects of iron-based nanoparticles on freshwater phytoplankton Scenedesmus armatus and Microcystis aeruginosa strains

Zero-valent nano-iron particles (nZVI) are increasingly present in freshwater aquatic environments due to their numerous applications in environmental remediation. However, despite the broad benefits associated with the use and development of nZVI nanoparticles, the potential risks of introducing them into the aquatic environment need to be considered. Special attention should be focused on primary producer organisms, the basal trophic level, whose impact affects the rest of the food web. Although there are numerous acute studies on the acute effects of these nanoparticles on photosynthetic primary producers, few studies focus on long-term exposures. The present study aimed at assessing the effects of nZVI on growth rate, photosynthesis activity, and reactive oxygen activity (ROS) on the freshwater green algae Scenedesmus armatus and the cyanobacteria Microcystis aeruginosa. Moreover, microcystin production was also evaluated. These parameters were assessed on both organisms singly exposed to 72 h-effective nZVI concentration for 10% maximal response for 28 days. The results showed that the cell growth rate of S. armatus was initially significantly altered and progressively reached control-like values at 28 days post-exposure, while M. aeruginosa did not show any significant difference concerning control values at any time. In both strains dark respiration (R) increased, unlike net photosynthesis (Pn), while gross photosynthesis (Pg) only slightly increased at 7 days of exposure and then became equal to control values at 28 days of exposure. The nZVI nanoparticles generated ROS progressively during the 28 days of exposure in both strains, although their formation was significantly higher on green algae than on cyanobacteria. These data can provide additional information to further investigate the potential risks of nZVI and ultimately help decision-makers make better informed decisions regarding the use of nZVI for environmental remediation.

Advantages and disadvantages of maintaining the mandatory use of masks in health centers and nursing homes in Spain. How and when is it justified to maintain it?

We address the advantages and disadvantages of maintaining the mandatory use of masks in health centers and nursing homes in the current epidemiological situation in Spain and after the declaration of the World Health Organization on May 5, 2023 of the end of COVID-19 as public health emergency. We advocate for prudence and flexibility, respecting the individual decision to wear a mask and emphasizing the need for its use when symptoms suggestive of a respiratory infection appear, in situations of special vulnerability (such as immunosuppression), or when caring for patients with those infections. At present, given the observed low risk of severe COVID-19 and the low transmission of other respiratory infections, we believe that it is disproportionate to maintain the mandatory use of masks in a general way in health centers and nursing homes. However, this could change depending on the results of epidemiological surveillance and it would be necessary to reconsider returning to the obligation in periods with a high incidence of respiratory infections.

Human papillomavirus infection and lung adenocarcinoma: special benefit is observed in patients treated with immune checkpoint inhibitors

BACKGROUND

Human papilloma virus (HPV) has been associated with the development and modulation of response in a series of neoplasms. In the case of lung adenocarcinoma, its role in etiology and pathogenesis is still controversial. Considering that this infection brings foreign epitopes, it could be of prognostic significance in patients with lung adenocarcinoma treated with immunotherapy.

METHODS

In a retrospective cohort study we evaluated the presence of HPV genomic material in lung adenocarcinoma primary lesions with the INNO-LiPA platform. Viral replication was also evaluated by detecting the presence of oncoprotein E6/E7 messenger RNA (mRNA) by quantitative RT-PCR. To confirm possible hypotheses regarding viral oncogenesis, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1 (HIF1) were evaluated with stromal fibrosis and immunoscore.

RESULTS

A total of 133 patients were included in the analysis, of whom 34 tested positive for HPV, reaching an estimated prevalence of 25.6% [95% confidence interval (CI) 18.2% to 32.9%]. E6/7 mRNA was identified in 28 out of the 34 previously positive cases (82.3%). In immune checkpoint inhibitor (ICI)-treated patients, the median overall survival reached 22.3 months [95% CI 19.4 months- not reached (NR)] for HPV-negative and was not reached in HPV-positive (HPV+) ones (95% CI 27.7-NR; P = 0.008). With regard to progression-free survival, HPV- patients reached a median of 9.2 months (95% CI 7.9-11.2 months) compared to 14.3 months (95% CI 13.8-16.4 months) when HPV was positive (P = 0.001). The overall response rate for HPV+ patients yielded 82.4% compared to 47.1% in negative ones. No differences regarding programmed death-ligand 1, VEGF, HIF1, stromal fibrosis, or immunoscore were identified.

CONCLUSIONS

In patients with HPV+ lung adenocarcinoma, a significant benefit in overall response and survival outcomes is observed.

Burnout syndrome assessment among Spanish oral surgery consultants: A two populations comparative pilot study

Background

The professional Burnout Syndrome (BOS) or Burnout is considered a professional disease made up of three interrelated dimensions (emotional exhaustion, depersonalization and lack of personal fulfillment). BOS has been documented to most severely affect the healthcare professions, especially dentists. On the other hand, its appearance has been documented at an early age, during dental training. However, there are no studies that analyze its incidence in professionals dedicated to Oral Surgery and Implantology, determining the age of onset and related factors.

Material and Methods

The modified Maslach questionnaire was carried out anonymously among the professors and students of the Master of Oral Surgery and Implantology at the Complutense University of Madrid. A total of 36 participants were enrolled in this study and the results of the modified Maslach Questionnaire were established into four groups [1st year (n=6), 2nd year (n=6), 3rd year (n=6) postgraduate students and clinical teachers (n=18)]. The following variables were recorded: Age, sex, years of experience, weekly hours of work, dedication on weekends and scope of work. The statistical analysis performed included Pearson's correlation, analysis of variance, Student's t-test, F-Anova, Chi-Square and Gamma correlation. Statistical Significance of the tests was established of p≤0.05.

Results

36 questionnaires were analyzed, of which 22.2% (n = 8) presented BOS, and 77.8% (n = 28) a medium risk of suffering it. The mean values and standard deviation ​​of emotional exhaustion (7.50 ± 2.43; 9.83 ± 4.12; 15.83 ± 6.21; 30.22 ± 7.86), depersonalization (5.50 ± 1.23; 50 ± 3.27; 11.33 ± 1.75; 17.56 ± 4.13), low personal fulfillment (39.67 ± 3.72; 39.33 ± 2.34; 43.17 ± 3, 55; 37.33 ± 5.51) and professional burnout (54.33 ± 2.66; 61.67 ± 2.88; 70.33 ± 5.43; 85.11 ± 9.05) in the four groups respectively. A significant association was found in the appearance of emotional exhaustion and depersonalization, years of experience, weekly work hours and the work environment.

Conclusions

BOS is a disease that can appear from 30 years of age, after 5 years of professional experience and when there is a clinical consultation of 40 hours a week. Oral Surgery and Implantology seems to be a risk activity for the manifestation of depersonalization.

Key words:Burnout syndrome, oral surgery, dental implants, students, clinical teachers, dental education.

Glycosaminoglycans Are Involved in the Adhesion of Candida albicans and Malassezia Species to Keratinocytes But Not to Dermal Fibroblasts

BACKGROUND AND OBJECTIVE

Superficial mycoses are some of the most common diseases worldwide. The usual culprits-yeasts belonging to the genera Malassezia and Candida-are commensal species in the skin that can cause opportunistic infections. We aimed to determine whether these yeasts use glycosaminoglycans (GAGs) as adhesion receptors to mediate binding to epithelial cells.

MATERIAL AND METHODS

In keratinocyte and dermal fibroblast cultures, we used rhodamine B and genistein to inhibit GAG synthesis to study the role these molecules play in the adhesion of Candida albicans and Malassezia species to cells. We also analyzed GAG involvement by means of enzyme digestion, using specific lyases.

RESULTS

Rhodamine B partially inhibited the adhesion of both fungi to keratinocytes but not to fibroblasts. Selective digestion of heparan sulfate enhanced the binding of Malassezia species to keratinocytes and of both fungi to fibroblasts. Chondroitin sulfate digestion decreased Calbicans adhesion to keratinocytes, but increased the adhesion of the filamentous forms of this species to fibroblasts.

CONCLUSIONS

Cell surface GAGs appear to play a role in the adhesion of Calbicans and Malasezzia species to keratinocytes. In contrast, their adhesion to fibroblasts appears to be enhanced by GAG inhibition, suggesting that some other type of receptor is the mediator.

Glycosaminoglycans Are Involved in the Adhesion of Candida albicans and Malassezia Species to Keratinocytes But Not to Dermal Fibroblasts

BACKGROUND AND OBJECTIVE

Superficial mycoses are some of the most common diseases worldwide. The usual culprits - yeasts belonging to the genera Malassezia and Candida - are commensal species in the skin that can cause opportunistic infections. We aimed to determine whether these yeasts use glycosaminoglycans (GAGs) as adhesion receptors to mediate binding to epithelial cells.

MATERIAL AND METHODS

In keratinocyte and dermal fibroblast cultures, we used rhodamine B and genistein to inhibit GAG synthesis to study the role these molecules play in the adhesion of Candida albicans (C. albicans) and Malassezia species to cells. We also analyzed GAG involvement by means of enzyme digestion, using specific lyases.

RESULTS

Rhodamine B partially inhibited the adhesion of both fungi to keratinocytes but not to fibroblasts. Selective digestion of heparan sulfate enhanced the binding of Malassezia species to keratinocytes and of both fungi to fibroblasts. Chondroitin sulfate digestion decreased C. albicans adhesion to keratinocytes, but increased the adhesion of the filamentous forms of this species to fibroblasts.

CONCLUSIONS

Cell surface GAGs appear to play a role in the adhesion of C albicans and Malasezzia species to keratinocytes. In contrast, their adhesion to fibroblasts appears to be enhanced by GAG inhibition, suggesting that some other type of receptor is the mediator.

Rapid identification and antimicrobial susceptibility testing of Gram-negative rod on positive blood cultures using MicroScan panels

Shortening the turnaround time of antimicrobial susceptibility testing (AST) of bacteria permits a significant reduction of patient morbidity, mortality, and cost. Conventional blood culture methods are the gold standard diagnostic test to guide management of patient with sepsis, but the conventional process requires at least 12 to 24 h after the blood culture has been flagged as positive due to requirement for pure colonies. We describe a simple and inexpensive method to obtain faster AST with MicroScan system (Beckman Coulter) directly from positive blood cultures. Conventional and direct identification and AST were performed simultaneously by both methods in 1070 blood cultures, and 9106 MICs were determinated. About 96.5% were correctly identified with the direct method. Overall, categorical agreement was 92.86%. We found 46 very major errors, but globally the results showed a good correlation with the standard method, particularly favorable for E. coli and K. pneumoniae, except amoxicillin-clavulanate and piperacillin-tazobactam. For P. mirabilis, betalactams antibiotics (except second- and third-generation cephalosporines) showed a good correlation, and also a good correlation was found for ciprofloxacine and gentamicine in P. aeruginosa and amoxicillin-clavulanate, ciprofloxacine, gentamicine, and cotrimoxazole in E. cloacae. This method has the main advantage of providing reliable results 1 day earlier, being a simple, fast, and cheap method for identification and antimicrobial susceptibility testing results from positive blood cultures.

An evidence-based bundle improves the quality of care and outcomes of patients with candidaemia

Background

Candidaemia is a leading cause of bloodstream infections in hospitalized patients all over the world. It remains associated with high mortality.

Objectives

To assess the impact of implementing an evidence-based package of measures (bundle) on the quality of care and outcomes of candidaemia.

Methods

A systematic review of the literature was performed to identify measures related to better outcomes in candidaemia. Eight quality-of-care indicators (QCIs) were identified and a set of written recommendations (early treatment, echinocandins in septic shock, source control, follow-up blood culture, ophthalmoscopy, echocardiography, de-escalation, length of treatment) was prospectively implemented. The study was performed in 11 tertiary hospitals in Spain. A quasi-experimental design before and during bundle implementation (September 2016 to February 2018) was used. For the pre-intervention period, data from the prospective national surveillance were used (May 2010 to April 2011).

Results

A total of 385 and 263 episodes were included in the pre-intervention and intervention groups, respectively. Adherence to all QCIs improved in the intervention group. The intervention group had a decrease in early (OR 0.46; 95% CI 0.23–0.89; P = 0.022) and overall (OR 0.61; 95% CI 0.4–0.94; P = 0.023) mortality after controlling for potential confounders.

Conclusions

Implementing a structured, evidence-based intervention bundle significantly improved patient care and early and overall mortality in patients with candidaemia. Institutions should embrace this objective strategy and use the bundle as a means to measure high-quality medical care of patients.

Psychotic symptoms following oxycodone withdrawal, case report and update

Opiate withdrawal-induced psychosis is an uncommon clinical manifestation. We present a 36-year-old male patient, with no prior personal or familiar psychiatric history, in treatment with several analgesic drugs (including oxycodone) for non-inflammatory chronic rachialgia. The patient is hospitalized after exhibiting psychotic symptomatology (delusions of harm and contamination, olfactory hallucinations, and aberrant behavior). This psychotic symptomatology first manifested after abruptly interrupting his prescribed oxycodone intake. It had a fluctuating course over time (alternating between lucid states and delusional ones) and eventually subsided after the prescription of antipsychotic drugs. In this case report, we describe the follow-up of the patient and discuss the influence and relevance of oxycodone withdrawal on the psychotic symptomatology.

Widespread use of Lactobacillus OppA, a surface located protein, as an adhesin that recognises epithelial cell surface glycosaminoglycans

Specific adherence is the first requisite that a microorganism has to fulfil to become established onto a mucosal surface. It was previously shown that the OppA surface protein of Lactobacillus salivarius Lv72 bound HeLa cell cultures through interaction with glycosaminoglycans (GAGs). To determine whether this is a peculiarity of that strain or whether it can be extended to other lactobacilli, 12 strains, belonging to six species, were confronted with HeLa-cell cultures in the presence of soluble GAGs. Interference was observed to six of them, heparan sulphate and chondroitin sulphate C being more interfering than chondroitin sulphate A or chondroitin sulphate B. Furthermore, inhibition of the biosynthesis of GAGs or their elimination from the cell surface with specific enzymes also resulted in reduced adherence. Analysis of the surface proteome of Lactobacillus crispatus Lv25 and of Lactobacillus reuteri RC14 revealed single proteins that immunoreacted with antibodies raised against OppA, the main adhesin of L. salivarius Lv72. Upon MALDI-TOF-TOF analysis, they were identified as OppA-like proteins, thus indicating that these proteins participate as adhesins in attachment of diverse lactobacilli to the surface of human epithelial cells.

Heavy metals immobilization capability of two iron-based nanoparticles (nZVI and Fe3O4): Soil and freshwater bioassays to assess ecotoxicological impact

The contamination by heavy metals constitutes an environmental problem of great importance in the last decades, and demands of society for clean environments are increasingly evident. To achieve this goal, several strategies have appeared for the in situ remediation of soil contamination caused by heavy metals. This study evaluated two types of iron-based nanoparticles, zero-valent iron nanoparticles (nZVI) and Fe₃O₄ nanoparticles, for the effective immobilization of Furthermore, we conducted a set of ecotoxicological bioassays: Microtox® Test, Caenorhabditis elegans Test, and Phytoplankton Toxicity Tests, on selected soil and aquatic test organisms to both, i) evaluate the potential ecotoxicological risks associated with nanoparticles treatment, and ii) to define sensitive organisms to be used as suitable bioindicators of heavy metals pollution. The application of 5% nZVI significantly reduced the amount of bioavailable heavy metals, which was effective from an ecotoxicity point of view as a reduction of the toxicity of was observed. Among the bioassays used, C. elegans seems the most effective reference organism in detecting changes in the toxicity of and therefore, C. elegans was found to be a sensitive heavy metals pollution bioindicator. When the Combination index (CI) was obtained to determine combined heavy metals interactions, the results indicated that toxicity would be higher than that expected for Pb, Cd and Zn individually considered, due to the proved antagonistic interactions of those toxicants. The obtained results suggested that nZVI nanoparticles are susceptible to be used as a soil remediation strategy for heavy metal pollution, although a short reactive lifespan must be considered, and therefore its effectiveness in long periods remains to be elucidated.

Two alkaline motifs in the Lactobacillus salivarius Lv72 OppA surface are important to its adhesin function

Glycosaminoglycans are involved in the attachment of Lactobacillus salivarius Lv72, a strain of vaginal origin, to HeLa cell cultures, indicating that they play a fundamental role in the attachment of mutualistic bacteria to the epithelium lining cavities where the normal microbiota thrives. The bacterial OppA protein has been proposed as an adhesin involved in this adherence since, once purified, it significantly interferes with attachment of the lactobacilli to HeLa cell cultures. In this article, the role of OppA is confirmed through the determination of its location at the cell surface and its ability to promote Lactobacillus casei and Lactococcus lactis adherence to eukaryotic cell cultures upon cloning and expression of oppA in these bacteria. The OppA sequence showed five potential domains for glycosaminoglycan-binding, and structural modelling of the protein showed that two of them were located in the vicinity of an OppA superficial groove whose width approached the diameter of the helical form of heparin in solution. Their involvement in the binding was demonstrated through substitution of critical basic amino acids by acidic ones, which resulted in loss of affinity for heparan sulphate and chondroitin sulphate depending on the domain mutated, suggesting that there might be a certain degree of specialisation. In addition, circular dichroism analysis showed that the spectrum changes induced by OppA-heparan sulphate binding were attenuated by the variant proteins, indicating that these motifs are the OppA recognition domains for the eukaryotic cell surface.

Oat-Cell Carcinoma of Primary Location in the Pericardium. A Case Report

A case of oat-cell carcinoma arising in the pericardium of a 51-year-old woman is described. The patient had multiple nodes; the largest was 2 × 1 cm. Two years later the patient presented with a tumor on her lower gum; this measured 2 mm and had similar characteristics to the previous one. The immunohistochemical study showed strong positivity for neuron-specific enolase. From review of the literature, it may be concluded that this is the first report of oat-cell carcinoma occurring in the pericardium.

Incidence and evolution of sepsis-induced cardiomyopathy in a cohort of patients with sepsis and septic shock

OBJETIVE

The aim of this study was to establish the incidence of septic cardiomyopathy (SM) in patients with sepsis and septic shock, to describe its characteristics and testing its evolution.

DESIGN

Prospective cohort study.

PARTICIPANTS

We included 57 consecutive patients admitted to Intensive Care Unit, who met criteria of sepsis and septic shock.

PRINCIPAL VARIABLES OF INTEREST

Clinical and biochemical variables were analyzed. An echocardiogram was performed in the first 24hours of admission, determining myocardial function parameters, and if the patients had left ventricular ejection fraction (LVEF)<50%) a second echocardiogram was performed.

AMBIT

Intensive medical and surgical Care Service for Adults in University Hospital.

RESULTS

The mean age of the patients was 62,1±16,3 years. 58% were males. 22.8% had left ventricular dysfunction. The mean LVEF in patients with MS was lower than those without SM (34.1±10.6 vs 60.7±6.94%, P<.001), with complete recovery, in survivors, after the acute event (LVEF at discharge 56.1±6.3%, P=.04). Patients with SM had higher levels of procalcitonin (47.1±35.4 vs 18.9±24.5; P=.02) and higher score on the Sequential Organ Failure Assessment (SOFA score) (9.91±3.82 vs 7.47±3.41; P=.037). Mortality was not significantly different between both groups [4 (30.8%) vs 4 (9.1%); P=.07].

CONCLUSIONS

SM is not uncommon and is related to a higher scores on the severity scales. In the survivors, LVEF normalized after the recovery of the acute event.

Evaluation of the Mycobacterium tuberculosis SO2 vaccine using a natural tuberculosis infection model in goats

The development of new vaccines against animal tuberculosis (TB) is a priority for improving the control and eradication of this disease, particularly in those species not subjected to compulsory eradication programmes. In this study, the protection conferred by the Mycobacterium tuberculosis SO₂ experimental vaccine was evaluated using a natural infection model in goats. Twenty-six goats were distributed in three groups: (1) 10 goats served as a control group; (2) six goats were subcutaneously vaccinated with BCG; and (3) 10 goats were subcutaneously vaccinated with SO₂. Four months after vaccination, all groups were merged with goats infected with Mycobacterium bovis or Mycobacterium caprae, and tested over a 40 week period using a tuberculin intradermal test and an interferon-γ assay for mycobacterial reactivity. The severity of lesions was determined at post-mortem examination and the bacterial load in tissues were evaluated by culture. The two vaccinated groups had significantly lower lesion and bacterial culture scores than the control group (P<0.05); at the end of the study, the SO₂ vaccinated goats had the lowest lesion and culture scores. These results suggest that the SO₂ vaccine provides some protection against TB infection acquired from natural exposure.

Electromyographic activity of the jaw muscles and mandibular kinematics in young adults with theoretically ideal dental occlusion: Reference values

Background

A necessary step to use neuromuscular analysis as diagnostic tool is to establish normal reference values for the physiological range in a healthy population. Surface electromyographic (sEMG) activity of the jaw muscles and mandibular kinematics were measured in young adults with theoretically ideal dental occlusion to determine normal reference values during different tasks. Differences between the sexes were evaluated.

Material and Methods

Forty young adults (20 men, 20 women; mean age 22.8 ± 3.9 years) with theoretically ideal dental occlusion were selected using very restrictive criteria. sEMG activity of the anterior temporalis (AT), posterior temporalis, masseter (MA), and suprahyoid muscles were evaluated in the rest position and during swallowing, mastication, and clenching. Mandibular kinematics in the rest position and during maximum excursions were assessed. Asymmetry, activity, and torque indices and MA/AT ratios were calculated.

Results

For all muscles, sEMG values were 1.01-3.57 µV at rest, 3.50-10.85 µV during swallowing, and 41.04-86.59 µV during mastication. During clenching, values were 230.08-243.55 µV for the AT and MA muscles. Mean total asymmetry, activity, and torque indices at rest were 20.34 %, -15.04 %, and 19.02 %, respectively; during clenching, these values were 6.14 %, -2.62 %, and 4.46 %. MA/AT ratios were near 1. Kinematic measurements during lateral excursion, protrusive and maximum opening were 7.54, 8.44, and 37.38 mm respectively; lateral mandibular shift was 1.41 mm; free way and lateral displacement at rest were 1.40 and 0.26 mm. Right MA activity during mastication and clenching was higher in men than women.

Conclusions

Reference values for sEMG activity and mandibular kinematics were determined. Some muscular asymmetry and torque were observed.

Key words:Electromyography, masticatory muscles, kinesiography, jaw movements, normal dental occlusion, sexual dimorphism.