Respiratory virus detection among healthcare professionals in Brazil: work-related contact and episode recurrence during the COVID-19 pandemic.

OBJECTIVES: Since the beginning of the COVID-19 pandemic, changes in the circulation of respiratory viruses have been observed after measures to control the spread of SARS-CoV-2 were implemented. In this sense, we aimed to understand the circulation of the respiratory virus and its impact in a controlled healthy population of healthcare professional (HCP) volunteers in phase III of the clinical trial of the ChadOx nCoV1 conducted in São Paulo, Brazil. STUDY DESIGN: This was a nested observational cohort study within a clinical trial. METHODS: We performed RT-qPCR to detect SARS-CoV-2, influenza virus A and B (IVA and IVB), respiratory syncytial virus (RSV), human rhinovirus (HRV), human metapneumovirus (hMPV), human coronaviruses (hCoVs: HKU-1, NL63, OC43, and 229-E), parainfluenza virus (PiV) I-IV, and q-PCR for adenovirus in nasopharyngeal and oropharyngeal samples obtained from HCP enrolled in the clinical trial to assess respiratory viruses infection among vaccinated and non-vaccinated. RESULTS: From July 2020 to January 2022, 876 samples were included from 737 volunteers (median age: 33 years, 62.9% female). New episodes were registered for 119 individuals. We observed an overall positivity of 37.7% for SARS-CoV-2 and 16.4% for other respiratory viruses; HRV was the second most detected virus (8%), followed by RSV (2.4%). Fully vaccinated individuals accounted for 53.3% of collected samples, and 52.9% presented at least one respiratory virus infection, with SARS-CoV-2 being the most predominant etiologic agent (62.3%). Influenza and hMPV were not detected among the tested samples. Among the subjects that presented more than one episode, SARS-CoV-2 and HRV infections were related to direct contact with patients (P < 0.002). CONCLUSIONS: Data show high infection rates among HCPs even under mask policies and contact precautions, highlighting the need for improvement in infection control measures in this population regardless of the vaccination program.

A laboratory evaluation of cell viability, radiopacity and tooth discoloration induced by regenerative endodontic materials.

AIM: To analyse the cytotoxicity, colour change and radiopacity of MTA Flow (MTA), UltraCal XS (UC) and Bio-C Temp (BT). METHODOLOGY: Human dental pulp cells (hDPCs) stimulated with lipopolysaccharide (LPS) were placed in contact with several dilutions of culture media previously exposed to the experimental materials and tested for cell viability using MTT. Bovine teeth were prepared to simulate an open apex and to mimic extensive crown fracture. The roots were filled with a mixture of agar and blood, and the materials placed over this mixture. The control group consisted of teeth filled only with agar and blood. Colour assessment analyses were performed before and immediately after material insertion and repeated at 30, 45 and 60 days using a spectrophotometer. The total colour change (ΔEab , ΔE00 and whiteness index (WI)) was calculated based on the CIELAB colour space. Digital radiographs were acquired for radiopacity analysis. Cell viability was analysed by one-way anova, whilst differences in colour parameters (ΔEab , ΔE00 and WI) were assessed by two-way repeated measures anova (α = 0.05). Tukey's test was used to compare the experimental groups, and Dunnett's test was used to compare the experimental groups with the control group. RESULTS: MTA, UC and BT had similar cell viability to that of the control group (DMEM) (P > 0.05), except for the BT group at the 1 : 1 and 1 : 2 dilutions, which had significantly lower viability (P < 0.001). All materials were associated with discoloration values greater than what is considered to be the acceptable threshold, and BT resulted in less or similar tooth colour change than MTA and UC, respectively. Decreasing radiopacity over time was observed only in the MTA group (P = 0.007). Lower values of radiopacity were found in the BT group compared with the UC and MTA groups (P < 0.001). CONCLUSIONS: The new bioceramic material (BT) had acceptable cell viability, similar to that of MTA and UC at the highest dilutions, and BT resulted in less tooth colour change than MTA and UC. Despite its lower radiopacity, BT was identified radiographically.

Immunolocalization of leptin and its receptor in the sheep ovary and in vitro effect of leptin on follicular development and oocyte maturation.

The aims of the study were to characterize leptin and it is receptor (LEPR) proteins immunoexpression in ovine ovaries and to evaluate the effects of leptin on development of secondary follicles cultured in vitro. The ovaries were collected and fixed for immunohistochemical analysis. Additional pairs of ovaries were collected and secondary follicles were isolated and cultured, for 18 days, in α-MEM+ alone or supplemented with 10 or 25 ng/mL of leptin. The antrum formation and fully grown oocytes rates were higher in 25 ng/mL leptin than all treatments. GSH levels and mitochondrial activity were higher in 10 or 25 ng/mL leptin than α-MEM+. 25 ng/mL leptin showed a higher percentage of MII than the α-MEM+. In conclusion, leptin and its receptor are expressed in ovine ovaries and 25 ng/mL leptin promoted higher in vitro maturation rates by improving follicular development, GSH levels and mitochondrial activity of ovine oocytes compared to control medium.

The Centre for Data and Knowledge Integration for Health (CIDACS): Linking Health and Social Data in Brazil.

The Centre for Data and Knowledge Integration for Health (CIDACS) was created in 2016 in Salvador, Bahia-Brazil with the objective of integrating data and knowledge aiming to answer scientific questions related to the health of the Brazilian population. This article details our experiences in the establishment and operations of CIDACS, as well as efforts made to obtain high-quality linked data while adhering to security, ethical use and privacy issues. Every effort has been made to conduct operations while implementing appropriate structures, procedures, processes and controls over the original and integrated databases in order to provide adequate datasets to answer relevant research questions. Looking forward, CIDACS is expected to be an important resource for researchers and policymakers interested in enhancing the evidence base pertaining to different aspects of health, in particular when investigating, from a nation-wide perspective, the role of social determinants of health and the effects of social and environmental policies on different health outcomes.

Risk factors for early onset prosthetic valve endocarditis: a case-control study.

BACKGROUND: Early onset prosthetic valve endocarditis (EO-PVE) is an infrequent complication of cardiac valve surgery. It is considered a healthcare-associated infection due to contamination of the prosthesis during the implant or in the early postoperative period. AIM: To evaluate which factors may be related to the acquisition of EO-PVE. METHODS: A nested case-control study was conducted from 2006 to 2016. Cases were patients who had definite prosthetic endocarditis by the modified Duke criteria up to 12 months of heart valve replacement. Cases and controls were matched by age, gender, date and type of surgery. FINDINGS: There were 26 cases and 78 controls, in 2496 valve surgeries. The median incidence of EO-PVE was 1.1%. Risk factors identified during surgery were: use of ≥2 cryoprecipitate units (odds ratio (OR): 5.95; 95% confidence interval (CI): 1.31-27.0) and ≥2 plasma units (OR: 2.73; 95% CI: 1.0-7.5). In the postoperative period, associated factors were bloodstream infection (OR: 14.00; CI: 1.49-131.77), pneumonia (4.38; 1.21-15.84), any infection (4.46; 1.63-12.21), central line for ≥2 weeks (5.33; 2.06-13.78), presence of dialysis catheter (3.22; 1.15-9.03), and new open chest surgery (3.89; 1.28-11.78). Mortality at 12 months was 34.6% in cases and 6.4% in controls (OR: 7.73; CI: 2.3-26.06). CONCLUSION: Cases had more infections, invasive procedures and surgical re-interventions in the early postoperative period, which favoured contamination of the newly implanted prosthesis. A preventive approach, with reinforcement of infection control practices, may curb the incidence of this condition.

Physical activity prevents alterations in mitochondrial ultrastructure and glucometabolic parameters in a high-sugar diet model.

Endurance exercise is a remarkable intervention for the treatment of many diseases. Mitochondrial changes on skeletal muscle are likely important for many of the benefits provided by exercise. In this study, we aimed to evaluate the effects that a regular physical activity (swimming without workload) has on mitochondrial morphological alterations and glucometabolic parameters induced by a high-sugar diet (HSD). Weaned male Wistar rats fed with a standard diet or a HSD (68% carbohydrate) were subjected to 60 minutes of regular physical activity by swimming (without workload) for four- (20 sessions) or eight-week (40 sessions) periods. After training, animals were euthanized and the sera, adipose tissues, and skeletal muscles were collected for further analysis. The HSD increased body weight after an 8-week period; it also increased the fat pads and the adipose index, resulting in glucose intolerance and insulin resistance (IR). Transmission electron microscopy showed an increase in alterations of mitochondrial ultrastructure in the gastrocnemius muscle, as well as a decrease in superoxide dismutase (SOD) activity, and an increase in protein carbonylation. Regular physical activity partially reverted these alterations in rats fed a HSD, preventing mitochondrial morphological alterations and IR. Moreover, we observed a decrease in Pgc1α expression (qPCR analysis) in STD-EXE group and a less pronounced reduction in HSD-EXE group after an 8-week period. Thus, regular physical activity (swimming without workload) in rats fed a HSD can prevent mitochondrial dysfunction and IR, highlighting the crucial role for physical activity on metabolic homeostasis.

GAND classification and volumetric assessment of unilateral cleft lip and palate malformations using cone beam computed tomography.

The aim of this study was to propose a classification for unilateral cleft lip and palate (UCLP) malformations based on cone beam computed tomography (CBCT) images, as well as to estimate the amount of bone necessary for grafting, and to evaluate the relationship of this volume with scores obtained using the classification. CBCT images of 33 subjects with UCLP were evaluated according to gap, arch, nasal, and dental parameters (GAND classification). Additionally, these defects were segmented and the amount of graft needed for alveolar bone grafting was estimated. The reproducibility of GAND classification was analyzed by weighted kappa test. The association of volume assessment with the classification (gap and nasal parameters) was verified using analysis of variance, while the intra-observer agreement was analyzed using the intra-class correlation coefficient. The intra-observer reproducibility of the classification ranged from 0.29 to 0.92 and the inter-observer agreement ranged from 0.29 to 0.91. There were no statistically significant values when evaluating the association of the volume with the classification (P>0.05). The GAND classification is a novel system that allows the quick estimation of the extent and complexity of the cleft. It is not possible to estimate the amount of bone needed for alveolar bone grafting based on the classification; individualized surgical planning should be done for each patient specifically.

Multimodal and non-linear optical microscopy applications in reproductive biology.

A plethora of optical techniques is currently available to obtain non-destructive, contactless, real time information with subcellular spatial resolution to observe cell processes. Each technique has its own unique features for imaging and for obtaining certain biological information. However none of the available techniques can be of universal use. For a comprehensive investigation of biological specimens and events, one needs to use a combination of bioimaging methods, often at the same time. Some modern confocal/multiphoton microscopes provide simultaneous fluorescence, fluorescence lifetime imaging, and four-dimensional imaging. Some of them can also easily be adapted for harmonic generation imaging, and to permit cell manipulation technique. In this work we present a multimodal optical workstation that extends a commercially available confocal microscope to include nonlinear/multiphoton microscopy and optical manipulation/stimulation tools. The nonlinear microscopy capabilities were added to the commercial confocal microscope by exploiting all the flexibility offered by the manufacturer. The various capabilities of this workstation as applied directly to reproductive biology are discussed. Microsc. Res. Tech. 79:567-582, 2016. © 2016 Wiley Periodicals, Inc.

Impairment of toll-like receptors 2 and 4 leads to compensatory mechanisms after sciatic nerve axotomy.

BACKGROUND: Peripheral nerve injury results in retrograde cell body-related changes in the spinal motoneurons that will contribute to the regenerative response of their axons. Successful functional recovery also depends on molecular events mediated by innate immune response during Wallerian degeneration in the nerve microenvironment. A previous study in our lab demonstrated that TLR 2 and 4 develop opposite effects on synaptic stability in the spinal cord after peripheral nerve injury. Therefore, we suggested that the better preservation of spinal cord microenvironment would positively influence distal axonal regrowth. In this context, the present work aimed to investigate the influence of TLR2 and TLR4 on regeneration and functional recovery after peripheral nerve injury. METHODS: Eighty-eight mice were anesthetized and subjected to unilateral sciatic nerve crush (C3H/HeJ, n = 22, C3H/HePas, n = 22; C57Bl6/J, n = 22 and TLR2(-/-), n = 22). After the appropriate survival times (3, 7, 14 days, and 5 weeks), all mice were killed and the sciatic nerves and tibialis cranialis muscles were processed for immunohistochemistry and transmission electron microscopy (TEM). Gait analysis, after sciatic nerve crushing, was performed in another set of mice (minimum of n = 8 per group), by using the walking track test (CatWalk system). RESULTS: TLR4 mutant mice presented greater functional recovery as well as an enhanced p75(NTR) and neurofilament protein expression as compared to the wild-type strain. Moreover, the better functional recovery in mutant mice was correlated to a greater number of nerve terminal sprouts. Knockout mice for TLR2 exhibited 30 % greater number of degenerated axons in the distal stump of the sciatic nerve and a decreased p75(NTR) and neurofilament protein expression compared to the wild type. However, the absence of TLR2 receptor did not influence the overall functional recovery. End-point equivalent functional recovery in transgenic mice may be a result of enhanced axonal diameter found at 2 weeks after lesion. CONCLUSIONS: Altogether, the present results indicate that the lack of TLR2 or the absence of functional TLR4 does affect the nerve regeneration process; however, such changes are minimized through different compensatory mechanisms, resulting in similar motor function recovery, as compared to wild-type mice. These findings contribute to the concept that innate immune-related molecules influence peripheral nerve regeneration by concurrently participating in processes taking place both at the CNS and PNS.

Performance of an artefact reduction algorithm in the diagnosis of in vitro vertical root fracture in four different root filling conditions on CBCT images.

AIM: To evaluate the influence of an artefact reduction algorithm (ARA) and several root filling materials on the detection of root fractures on cone-beam computed tomography (CBCT) images. METHODOLOGY: Forty-four teeth were divided into control and fractured groups and scanned on a Picasso Trio CBCT device under four conditions: unrestored, filled with gutta-percha cones, cast-gold or fibreglass posts; either with or without applying the ARA. Three calibrated examiners assessed the images. ROC analysis, anova and pairwise Tukey LSD test were performed. RESULTS: No significant difference between the groups with and without the ARA was observed. There was no significant interaction between the algorithm and root condition. On the other hand, there was a significant difference in the mean values of sensitivity (Sn) and accuracy (Ac) amongst the different root filling groups (P ≤ 0.001). CONCLUSIONS: The application of the ARA did not influence the diagnosis of root fractures, and its effects did not depend on root conditions. In relation to the filling materials, gold posts reduced the overall CBCT diagnostic ability, regardless of the use of the ARA.

Effect of different helminth extracts on the development of asthma in mice: The influence of early-life exposure and the role of IL-10 response.

It is not currently clear whether different parasites have distinct effects on the airway inflammatory response in asthma and whether exposure in early life to helminths have a stronger impact in a potential inhibitory effect on asthma. The aim of this study is to evaluate the effect of exposure to different helminth extracts on the development of allergic pulmonary response in mice, including early-life exposure. Different helminth extracts (Angiostrongylus costaricensis, Angiostrongylus cantonensis and Ascaris lumbricoides) were studied in female adult BALB/c and C57BL/6 IL-10-deficient mice in a protocol of murine asthma, injected intraperitoneally in different periods of exposure (early, pre-sensitization and post-sensitization). Cell counts in bronchoalveolar lavage (BAL), eosinophil peroxidase (EPO) from lung tissue, cytokine levels from BAL/spleen cell cultures, and lung histology were analyzed. Airway cellular influx induced by OVA was significantly inhibited by extracts of A. cantonensis and A. lumbricoides. Extracts of A. lumbricoides and A. costaricensis led to a significant reduction of IL-5 in BAL (p < 0.001). Only the exposure to A. lumbricoides led to an increased production of IL-10 in the lungs (p < 0.001). In IL-10-deficient mice exposed to A. costaricensis pre-sensitization, eosinophil counts and IL-5 levels in BAL and EPO in lung tissue were significantly reduced. In the early exposure to A. cantonensis, lung inflammation was clearly inhibited. In conclusion, different helminth extracts inhibit allergic lung inflammation in mice. IL-10 may not play a central role in some helminth-host interactions. Early exposure to helminth extracts could be a potential strategy to explore primary prevention in asthma.

Helminth extracts inhibit eosinophilic inflammation in a murine model of allergic rhinitis

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Development and reproduction of Spodoptera eridania (Lepidoptera: Noctuidae) and its egg parasitoid Telenomus remus (Hymenoptera: Platygastridae) on the genetically modified soybean (Bt) MON 87701×MON 89788.

Genetically modified crops with insect resistance genes from Bacillus thuringiensis Berliner (Bt-plants) are increasingly being cultivated worldwide. Therefore, it is critical to improve our knowledge of their direct or indirect impact not only on target pests but also on non-target arthropods. Hence, this study evaluates comparative leaf consumption and performance of Spodoptera eridania (Cramer), a species that is tolerant of the Cry1Ac protein, fed with Bt soybean, MON 87701×MON 89788 or its near [corrected] non-Bt isoline. Using this species as a model, we assessed [corrected] the comparative performance of the egg parasitoid Telenomus remus Nixon on eggs of S. eridania produced from individuals that fed on these two soybean genotypes [corrected] as larvae. Results showed that Bt soybean did not affect pest foliage consumption, but did reduce larvel duration by two days despite larvae in both treatments having six instars. Nevertheless, survival of S. eridania larvae, pupal weight, sex ratio, fecundity and longevity of female moths, and egg viability did not differ between Bt and non-Bt soybeans. Adult longevity of S. eridania males was increased when caterpillars were fed with Bt soybean versus the near isoline. No adverse effects of this technology were observed for the egg parasitoid T. remus. [corrected].

Comparison of median and paramedian regions for planning palatal mini-implants: a study in vivo using cone beam computed tomography.

The purpose of this study was to compare the bone height at the median and paramedian sites of the hard palate using cone beam computed tomography (CBCT). CBCT images of 110 subjects were selected and the palatal bone height measured in the coronal view of multiplanar reconstruction (MPR) images at the midsagittal site and at paramedian sites, 3mm and 6mm bilaterally, in the region of the upper first premolars; NemoCeph 3D software was used. Intra-observer and inter-observer agreement was assessed using the intra-class correlation coefficient. Differences between the median site and paramedian sites were calculated with the Friedman test. No significant differences were found among the sites evaluated (P>0.05). Paramedian sites at 3mm and 6mm bilaterally from the palatal suture showed comparable height to the central site. The observed comparable bone height might be helpful in increasing the choice of host sites for palatal implants. The alternative placement of implants in the paramedian regions is not indicated as a viable treatment option for patients with insufficient bone height, but represents a feasible alternative for mini-implant insertion in patients in whom the middle region should be avoided.

A comparison of the mandibular index on panoramic and cross-sectional images from CBCT exams from osteoporosis risk group.

UNLABELLED: Osteoporosis is a degenerative disease that primarily affects postmenopausal women. Based on panoramic radiographs, several assessment methods have been proposed for the diagnosis and evaluation of bone changes and as a predictor of osteoporosis for example the mandibular index. INTRODUCTION: The purpose of this study is to compare the assessment of mandibular indices on panoramic and cross-sectional images. METHODS: Forty-four cone beam computed tomography (CBCT) images from postmenopausal female subjects aged more than 45 years without systemic changes were selected for this study. From those images, cross-sectional and panoramic reconstruction images were assembled into a template for evaluation. The evaluation was conducted by observing the panoramic images and parasagittal sections. The appearance of the inferior cortex of the mandible was classified according to the mandibular index: C1, the endosteal margin of the cortex was even and sharp; C2, the endosteal margin presented semilunar defects or appeared to form endosteal cortical residues; or C3, the cortical layer formed heavy endosteal cortical residues and was clearly porous. RESULTS: Based on Wilcoxon statistical test (p > 0.01), the data showed no statistically significant difference between the exams. CONCLUSION: The mandibular index assigned in tomographic images is comparable to that obtained in panoramic images, indicating a valid use of the index in CBCT images, which can lead to the identification of patients with bone mass loss and a premature referral to further exams and treatment.

Efeito analgésico e anti-inflamatório do extrato aquoso das folhas de trevo-roxo (Scutellaria agrestis A. St. -Hil. ex Benth. - Lamiaceae) em roedores / Analgesic and anti-inflammatory effect of the aqueous extract of "trevo-roxo" (Scutellaria agrestis A. St. -Hil. ex Benth. - Lamiaceae) leaves in rodents

Scutellaria agrestis é utilizada por comunidades ribeirinhas do Amazonas principalmente para o tratamento de otites por via tópica utilizando-se o extrato bruto obtido por maceração. O presente trabalho visou investigar preliminarmente o perfil fitoquímico, a segurança toxicológica e as ações analgésica, anti-inflamatória e antiedematogência do extrato aquoso das folhas de S. agrestis. Foram coletados 80 indivíduos da espécie no horto medicinal da Universidade Nilton Lins, Manaus, Brasil. O perfil fitoquímico foi obtido por meio de prospecção da droga vegetal para heterosídeos cianogênicos, terpenos, compostos fenólicos e alcaloides. A toxicologia foi avaliada pelo teste de toxicidade aguda. As atividades analgésicas/ anti-inflamatórias foram analisadas por meio dos testes de formalina em camundongos e a atividade antiedematogência, pelo teste de edema de pata em ratos. Os metabólitos detectados foram fenóis (taninos hidrolisáveis, cumarinas e várias classes de flavonoides) e terpenos (esteroides livres, saponinas). Não foi possível estabelecer DL50, haja visto que o extrato não provocou a morte de nenhum animal durante o teste de toxicidade aguda, provavelmente devido à ausência de heterosídeos cianogênicos na sua composição. Apesar de não provocar morte, considerou-se que o extrato apresenta uma discreta toxicidade, uma vez que foi observada a ocorrência de espasmos na primeira hora de observação dos animais. O extrato apresentou ainda efeito analgésico e anti-inflamatório significativo nas doses de 30, 100 e 300 mg/kg pelo teste da formalina, sendo o resultado na maior dose equivalente ao obtido com a droga padrão (fentanil). No entanto, não observamos efeito antiedematogênico nas doses testadas durante as 5 horas de registro do edema de pata. Os resultados obtidos nesta pesquisa conferem base científica preliminar quanto à segurança e ao efeito analgésico e antiinflamatório da droga vegetal, o que indica que tal espécie é promissora e expressamente recomendada para maiores estudos farmacológicos in vitro e in vivo.

The Scutellaria agrestis is used by Amazonas riverine communities, especially for otitis externa topical treatment, by using the crude extract obtained by maceration. This study aimed to investigate the preliminary phytochemical profile, the safety/toxicity and the analgesic, anti-inflammatory and antiedematogenic activities of the aqueous extract of the S. agrestis leaves. Eighty individuals were collected at the Nilton Lins University medicinal garden, Manaus, Brazil. The phytochemical profile was obtained through a plant drug survey for cyanogenic heterosides, terpenes, alkaloids and phenolic compounds. The extract safety was evaluated by acute toxicity test. Analgesic and anti-inflammatory activities were accessed using formalin test in mice and the antiedematogenic activity, using paw edema test in mice. We detected phenolic (hydrolysable tannins, coumarins and several classes of flavonoids) and terpenoid (free steroids, saponins) metabolites. We could not establish LD50 because no animals died during the acute toxicity test, probably because of the absence of cyanogenic glycosides on the composition of the extract. However, we found that the extract is slightly toxic as animal spasms were observed in the first hour of the test. The extract showed significant analgesic and anti-inflammatory activity on the formalin test (30, 100 and 300 mg/kg p.o.), and the highest dose result was equivalent to the standard drug (Fentanyl). However, no significant antiedematogenic effect was observed during the paw edema test. The results obtained in this study provide preliminary scientific basis about the safety and analgesic/anti-inflammatory actions of the aqueous extract of S. agrestis, which indicates that this species is a promising option for further in vitro and in vivo pharmacological studies.

Counselling and self-management therapies for temporomandibular disorders: a systematic review.

The aim of this review was to investigate the effectiveness of counselling and other self-management-based therapies on muscle and temporomandibular joint (TMJ) pain relief and increasing the functional abilities of patients with temporomandibular disorders (TMD). A systematic literature review was conducted by three independent reviewers and included articles published up to 2012. PubMed and Cochrane Library electronic databases were used in addition to hand-searching to assess clinical outcomes for counselling and self-management approaches for TMD treatment. The review yielded 581 records that were narrowed down to 7. All included studies were classified as blind-randomized controlled clinical trials. The selected articles analysed revealed that counselling was able to improve tenderness upon masticatory muscle palpation and maximum mouth opening with and without pain in patients with TMD, with similar results to those of interocclusal appliances approaches. Thus, counselling- and self-management-based therapies could be considered a conservative low-cost and beneficial treatment alternative for treating TMD to potentially improve psychological domains and remove harmful behaviours for the control of the signs and symptoms of TMD.