Advances in surface design and biomedical applications of magnetic nanoparticles.

Despite significant efforts by scientists in the development of advanced nanotechnology materials for smart diagnosis devices and drug delivery systems, the success of clinical trials remains largely elusive. In order to address this biomedical challenge, magnetic nanoparticles (MNPs) have gained attention as a promising candidate due to their theranostic properties, which allow the simultaneous treatment and diagnosis of a disease. Moreover, MNPs have advantageous characteristics such as a larger surface area, high surface-to-volume ratio, enhanced mobility, mass transference and, more notably, easy manipulation under external magnetic fields. Besides, certain magnetic particle types based on the magnetite (Fe3O4) phase have already been FDA-approved, demonstrating biocompatible and low toxicity. Typically, surface modification and/or functional group conjugation are required to prevent oxidation and particle aggregation. A wide range of inorganic and organic molecules have been utilized to coat the surface of MNPs, including surfactants, antibodies, synthetic and natural polymers, silica, metals, and various other substances. Furthermore, various strategies have been developed for the synthesis and surface functionalization of MNPs to enhance their colloidal stability, biocompatibility, good response to an external magnetic field, etc. Both uncoated MNPs and those coated with inorganic and organic compounds exhibit versatility, making them suitable for a range of applications such as drug delivery systems (DDS), magnetic hyperthermia, fluorescent biological labels, biodetection and magnetic resonance imaging (MRI). Thus, this review provides an update of recently published MNPs works, providing a current discussion regarding their strategies of synthesis and surface modifications, biomedical applications, and perspectives.

The "Sniffin' Kids-PT" test: A smell test variant for Portuguese children.

OBJECTIVE: Olfactory tests tailored for children are essential, as diagnosing olfactory dysfunction at these ages can be challenging. The 16-item "Sniffin' Sticks" is reliable and easy to perform. To the best of our knowledge, there is currently no validated olfactory test for the Portuguese pediatric population. This study aimed to adapt and validate the "Sniffin' Sticks" olfactory test for the Portuguese pediatric population. METHODS: Between August 2020 and September 2021, 354 children aged between 6 and 17years old enrolled in the study, 336 healthy children with a normal sense of smell, and 18 anosmic children with Kallmann syndrome. The study consisted of two parts. Firstly, the "Sniffin' Sticks" olfactory identification test was applied to healthy children and the odors with statistically significant low identification rates were excluded. A modified version of "Sniffin' Sticks" was defined and named "Sniffin' Kids-PT" test. Secondly, normative data were assessed and test-retest and validation tests were performed. RESULTS: Apple and Cloves odors were identified with a low rate and were excluded from the "Sniffin' Sticks" olfactory test. In the modified 14-item "Sniffin' Kids-PT", scoring <6 (from 6-8years old), <7 (from 9-11years old) or <8 (from 12-14years old and 15-17years old) was indicative of olfactory dysfunction. The test-retest reliability was good (r=0.81; P<0.001) and the differences between scores of healthy children and anosmic children were statistically significant (U213=13.00; P<0.001). CONCLUSION: The modified "Sniffin' Kids-PT" is a reliable test to discriminate between normosmia and olfactory dysfunction in Portuguese children over 5years old.

Complications associated with submental liposuction: a scoping review.

BACKGROUND: Liposuction is one of the most commonly performed cosmetic procedures worldwide. Complications associated with submental liposuction are rare. However, when they occur they are significant and can cause disfiguring consequences. The objective of this study was evaluated complications from submentual liposuction in literature and description of clinical experience of complication after submentual liposuction. MATERIAL AND METHODS: At first, a scoping review was carried out online search with no time restrictions for complications after submental liposuction was performed in the databases Medline / PubMed, Embase, and Web of Science. The variables analyzed were: age, sex, type of esthetic procedure, anesthesia, complications, time after Procedure, treatment, follow-up care, and sequelae. Then, a case of a patient with submental hematoma after an aesthetic procedure for submental liposuction was described. RESULTS: Firstly, 539 articles were selected, after application of the inclusion criteria, 4 studies were included. Most cases were female (8:1), with a mean age of 55.77 years. Postoperative complications were found, such as submental depression, submental edema, hypertrophic scar formation, scar contracture, cervical necrotizing fasciitis, Cervico-facial dystonia and transient facial nerve paralysis. The follow-up period for cases ranged from 3 to 12 months. The clinical case presented there was no sequelae. CONCLUSIONS: Submental liposuction requires the surgeon's attention. Anatomical knowledge, correct clinical and surgical management, diagnosis, and immediate approach to adverse situations are points that must be respected in this type of esthetic procedure to avoid more serious complications.

Nontuberculous Mycobacteria in Portugal: Trends from the last decade.

INTRODUCTION AND OBJECTIVES: Nontuberculous mycobacteria (NTM) are opportunistic human pathogens found in the environment. The transmission seems to be associated with inhalation of aerosol droplets, ingestion or trauma events. Recent studies indicate that NTM disease is increasing worldwide, however, the true clinical impact of NTM infections is difficult to determine due to challenges in discriminating between disease and colonization as they are ubiquitous in the environment. In addition, understanding the epidemiology of NTM is difficult and has not yet been established. In this work, we used a country NTM representative collection from the National Reference Laboratory for Tuberculosis (NRL-TB) of the National Institute of Health (INSA), to characterize the circulation trends of NTM species in Portugal and the most affected regions, contributing to a better understanding of the NTM epidemiology. MATERIAL AND METHODS: We conducted a nationwide retrospective study where all individuals with positive NTM cultures at the NRL-TB of the INSA from 2014 to December 2020 were included. Positive cultures were identified using GenoType Mycobacterium CM/AS® (Hain Lifescience) according to manufacturer's instructions, or hsp65 DNA sequencing as previously described. Social-demographic data from patients were also analyzed and patients classified into 3 groups according only to microbiological data, "definite NTM disease", "NTM colonization" and, "possible NTM disease". RESULTS: In the period 2014-2020, the NRL-TB performed 50397 cultures. Among these, 1118 cultures were NTM positive retrieved from 944. Most of our cases were in patients whose mean age was 64±15.9 years, and no significant differences between gender was observed, although more frequent in male patients. Overall, from the 944 cases, we were able to identified 93 "definite NTM disease" cases and 79 "possible NTM disease". Mycobacterium avium complex (MAC) (40,8%), Mycobacterium abscessus-chelonae complex (MABC) (9,6%) and Mycobacterium fortuitum (6,3%) were responsible for most of the infections. The geographical distribution of NTM cases varied significantly and was possible to observe that was independent of population density. The region were most cases occurred was Lisbon Metropolitan Area (31,9%), followed by North (25,3%) and Centre (24,4%), however North region has the highest number of "definite NTM disease" cases (n=33). CONCLUSIONS: This is the first national wide epidemiological study on this subject, contributing to a better understanding of NTM dynamics in Portugal. MAC was the NTM species responsible for the majority of infections and, LMA the region with the highest number of cases. It was also possible to conclude that the number of NTM isolates is independent of the demography of the region.

Is there an association between the use of antidepressants and complications involving dental implants? A systematic review and meta-analysis.

The aim of this systematic review was to evaluate published evidence on the association between the use of antidepressants and complications involving dental implants. Two reviewers independently performed electronic searches of the MEDLINE/PubMed, Cochrane Library, and Scopus databases for relevant articles published up to May 30, 2019. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Newcastle-Ottawa Scale was used for the appraisal of the methodological quality of the studies included. A meta-analysis was performed to determine the risk of dental implant failure in individuals taking antidepressants. Five comparative observational studies were selected for this review; these included a total of 2056 participants with 5302 implants. The results suggest a risk ratio of 3.73 (95% confidence interval 1.85-7.52, P=0.0002) for implant failure in antidepressant users submitted to oral rehabilitation when compared to non-users. However, these studies did not present methodological rigour or standardize the drugs used. Thus, there is insufficient evidence for an association between antidepressant use and dental implant complications.

Investigation of oral atopic diseases: Correlation between geographic tongue and fungiform papillary glossitis.

INTRODUCTION: The correlation between oral lesions and atopy is not new, but few studies have investigated the prevalence of mucosal changes in diseases within the atopic spectrum, leading to conflicting data. Some studies found a possible relationship between geographic tongue, transient lingual papillitis and atopic diseases. AIM: To investigate the frequency of geographic tongue and fungiform papillary glossitis in patients with atopic diseases, and its correlation with serum IgE levels and skin test results. MATERIAL AND METHODS: The sample was comprised of participants with atopic diseases paired with participants who received negative puncture skin tests. All were submitted to stomatological and medical evaluations, prick test and oral cytopathological. RESULTS: The female sex was more numerous in both groups. Mean age was 21 years. A total of 60 diagnoses of atopic diseases were obtained, with allergic rhinitis being the most prevalent. Fungiform papillary glossitis was the most frequent oral lesion in both groups, while geographic tongue was present in 2 cases (2%) in the test group and 2 (2%) in the control group. Atopic patients with fungiform papillary glossitis presented high serum IgE levels. In atopic patients with geographic tongue, the prick test positively identified extracts of Dermatophagoides pteronyssinus (100%) and Dermatophagoides farinae (100%). CONCLUSION: Due to the low frequency of geographic tongue lesions found in the study, it is no possible to conclude if that could be an oral manifestation of atopy. However fungiform papillary glossitis is a common alteration in atopic and non-atopic patients and has a relationship with high IgE serum levels. However, the consolidation of this result requires a larger sample size.

International league of associations for rheumatology recommendations for the management of psoriatic arthritis in resource-poor settings.

BACKGROUND: Psoriatic arthritis (PsA) is a challenging heterogeneous disease. The European League Against Rheumatism (EULAR) and the Group for Research and Assessment of Psoriasis and PsA (GRAPPA) last published their respective recommendations for the management of PsA in 2015. However, these guidelines are primarily based on studies conducted in resource replete countries and may not be applicable in countries in the Americas (except Canada and USA) and Africa. We sought to adapt the existing recommendations for these regions under the auspices of the International League of Associations for Rheumatology (ILAR). PROCESS: The ADAPTE Collaboration (2009) process for guideline adaptation was followed to adapt the EULAR and GRAPPA PsA treatment recommendations for the Americas and Africa. The process was conducted in three recommended phases: set-up phase; adaptation phase (defining health questions, assessing source recommendations, drafting report), and finalization phase (external review, aftercare planning, and final production). RESULT: ILAR recommendations have been derived principally by adapting the GRAPPA recommendations, additionally, EULAR recommendations where appropriate and supplemented by expert opinion and literature from these regions. A paucity of data relevant to resource-poor settings was found in PsA management literature. CONCLUSION: The ILAR Treatment Recommendations for PsA intends to serve as reference for the management of PsA in the Americas and Africa. This paper illustrates the experience of an international working group in adapting existing recommendations to a resource-poor setting. It highlights the need to conduct research on the management of PsA in these regions as data are currently lacking.Key Points• The paper presents adapted recommendations for the management of psoriatic arthritis in resource-poor settings.• The ADAPTE process was used to adapt existing GRAPPA and EULAR recommendations by collaboration with practicing clinicians from the Americas and Africa.• The evidence from resource-poor settings to answer clinically relevant questions was scant or non-existent; hence, a research agenda is proposed.

Retrospective pathological survey of pulmonary disease in free-ranging Amazon river dolphin Inia geoffrensis and tucuxi Sotalia fluviatilis.

The Amazon river dolphin Inia geoffrensis and tucuxi Sotalia fluviatilis are classified as Data Deficient species. Despite very limited knowledge on health and disease aspects of these species, the main threats to their conservation include incidental mortality in fishing gear, population fragmentation, habitat loss and environmental pollution. It is also suggested that underlying diseases may contribute to their mortality rates. Herein, we retrospectively describe gross and microscopic pulmonary lesions in free-ranging I. geoffrensis (n = 24) and S. fluviatilis (n = 28) found dead. Nearly 85% of the examined animals presented some kind of primary lung disease, wherein the main etiological diagnoses were verminous pneumonia by Halocercus brasiliensis (25%), bacterial pneumonia (25%) and a single case of meconium aspiration syndrome (1.9%). An etiology was not determined in 36.5% (19/52) of animals. These results indicate a high incidence of pulmonary pathology in these species, raising concerns about population impacts and potential zoonotic implications in some instances. These data may provide a scientific basis for future medical and conservation efforts focused on Amazonian dolphins.

Anti-Leishmania activity of essential oil of Myracrodruon urundeuva (Engl.) Fr. All.: Composition, cytotoxity and possible mechanisms of action.

Myracrodruon urundeuva (Engl.) Fr. All., commonly known as "aroeira-do-sertão", is a medicinal plant from Anacardiaceae family. In this study, the chemical composition of M. urundeuva essential oil (MuEO) was evaluated by gas chromatography-mass spectrometry (GC-MS), as well as its anti-Leishmania potential, cytotoxicity, and macrophage activation capability as possible antiprotozoal mechanism of action were assessed. Fourteen compounds were identified, which constituted 94.87% of total oil composition. The most abundant components were monoterpenes (80.35%), with ß-myrcene (42.46%), α-myrcene (37.23%), and caryophyllene (4.28%) as the major constituents. The MuEO inhibited the growth of promastigotes (IC50 205 ± 13.4 µg mL-1), axenic amastigotes (IC50 104.5 ± 11.82 µg mL-1) and decreased percentage of macrophage infection and number of amastigotes per macrophage (IC50 of 44.5 ± 4.37 µg⋅mL-1), suggesting significant anti-Leishmania activity. The cytotoxicity of MuEO was assessed by MTT test in Balb/c murine macrophages and by human erythrocytes lysis assay and low cytotoxicity for these cells was observed. The CC50 value against macrophages were 550 ± 29.21 µg mL-1, while cytotoxicity for erythrocytes was around 20% at the highest concentration assessed, with HC50 > 800 µg mL-1. While MuEO-induced anti-Leishmania activity is not mediated by increases in both lysosomal activity and nitric oxide production in macrophages, the results suggest the antiamastigote activity is associated with an immunomodulatory activity of macrophages due to an increase of phagocytic capability induced by MuEO. Thus, MuEO presented significant activity against Leishmania amazonensis, probably modulating the activation of macrophages, with low cytotoxicity to murine macrophages and human erythrocytes.

Alcohol abusive use increases facial trauma?

BACKGROUND: Trauma is among the main death causes and morbidity in the world and is often related to the use of alcohol and its abuse has reached massive proportions, no matter if the country is developed or not, being considered as public health problem. Since there are very few randomized and prospective studies in literature about the association of facial trauma and the use of alcohol, this study aims to investigate the impact of alcohol use in facial trauma. MATERIAL AND METHODS: This was a prospective and cross sectional study, involving facial trauma patients attended at Oral Maxillofacial Surgery Division of a State Hospital. Variables included patient's profile, trauma etiology, facial region involved, type of injury and treatment and days of hospitalization. AUDIT test was applied to identify risks and damages of alcohol use and chemical dependence. Absolute distribution, uni and mutilvaried percentages were made for data evaluation. Pearson's qui-squared and Fisher's Exact tests were also used. RESULTS: One hundred patients were evaluated. The patient's mean age was 33.50 years-old, 48% had between 17 and 29 years old, 28% had 30 to 39, and 24% 40 or more. Most of them were male (86%). The most frequent etiology was traffic accident (57%), the extraoral area was most committed (62%), the most frequent type of injury was fractures (78%) and the most affected bone was the mandible (36%). More than half of the patients (53%) had surgical treatment. 38% had their discharge from hospital right after the first attendance. The AUDIT most frequent answer was "moderate use" (46%) and use at risk (39%). There was significant difference between the use of alcohol (AUDIT) and hematoma (0.003) and number of days of hospitalization (p=0.005). CONCLUSIONS: In this study it was not observed association between alcohol consumption using the AUDIT and trauma etiology, but patient victims of traffic accidents were classified as with risk in the scale. Most of the trauma were caused by traffic accidents using motorcycles and occurred in young aged men.

Acne in women.

This review focuses on the subject of acne in women, a disease that is increasingly common and that can also affect men. Adult acne differs from the type of acne that occurs in teenagers, and it may persist beyond adolescence or have its onset at an older age (adult-onset acne or late acne). Acne can have a negative impact on the quality of life of patients at any age, leading to a negative body image and decrease in self-esteem, and in older patients it can result in discrimination in the workplace and in other social environments. Acne in women must be understood as a specific problem, and here we discuss the pathogenesis, clinical presentation, psychology and treatment of this very prevalent problem.

A possible relationship of human leucocyte antigens with psoriasis vulgaris and geographic tongue.

BACKGROUND: Geographic tongue (GT) is the most frequent oral lesion in psoriatic patients (PP), and genetic involvement in these conditions has been described. The association of psoriasis with GT is still not clear, and the study of human leucocyte antigen (HLA) may help clarify this relation. OBJECTIVE: The aim of this study was to investigate the association of HLA alleles with psoriasis vulgaris and GT. METHODS: Fifty-eight Brazilian PP, 29 GT patients and 125 healthy controls individuals were selected. Information on demographic and clinical characteristics was collected. All patients underwent an oral examination and blood collection for HLA typing. RESULTS: HLA-A did not show significant differences in frequencies among the groups. HLA-B*57 allele was more frequently found in PP and was not found in GT. HLA-B*58 allele was more frequently found in GT. HLA-C*06 and -C*18 alleles were associated with psoriasis. No significant differences in HLA-DRB1 and HLA-DQB1 were observed. CONCLUSION: HLA-B*58 was associated with GT and HLA-B*57 was possibly associated with psoriasis. This suggested that some GT cases may represent true oral psoriasis and some may represent only GT. Therefore, it is necessary to make this distinction and increase our sample size to improve the correct diagnosis and treatment of these conditions.

Burnout syndrome in oral and maxillofacial surgeons: a critical analysis.

The aim of this study was to determine the prevalence of burnout syndrome among Brazilian oral and maxillofacial surgeons and its relationship with socio-demographic, clinical, and habit variables. The sample of this study comprised 116 surgeons. The syndrome was quantified using the Maslach Burnout Inventory (General Survey), which defines burnout as the triad of high emotional exhaustion, high depersonalization, and low personal accomplishment. The criteria of Grunfeld et al. were used to evaluate the presence of the syndrome (17.2%). No significant differences between the surgeons diagnosed with and without the syndrome were observed according to age (P=0.804), sex (P=0.197), marital status (P=0.238), number of children (P=0.336), years of professional experience (P=0.102), patients attended per day (P=0.735), hours worked per week (P=0.350), use of alcohol (P=0.148), sports practice (P=0.243), hobbies (P=0.161), or vacation period per year (P=0.215). Significant differences occurred in the variables sex in the emotional exhaustion subscale (P=0.002) and use or not of alcohol in the personal accomplishment subscale (P=0.035). Burnout syndrome among Brazilian surgeons is average, showing a low personal accomplishment.

Análise de mutações no gene da hemocromatose e ferritina sérica em pacientes com porfiria cutânea tardía / Investigation of mutations in the gene of haemohcromatosis and the serum levels of ferritine in patients with porphiria cutanea tarda

A porfiria cutanea tardia (PCT) é uma doença que gera fotos sensibilidade pelo acúmulo de porfirinas decorrente do metabolismo de ferro alterado. O reflexo desse erro é observado bioquimicamente através das porfirinas urinárias, ferritina sérica entre outros parâmetros. Mutações no gene HFE1 são associadas tanto ao prognóstico quanto ao desencadeamento da PCT. No presente trabalho analisamos em 11 pacientes, acompanhados no ambulatório de dermatologia do Hospital Universitário Pedro Ernestro (HUPE), os genótipos do gene HFE1 para as mutações H63D, S65C e C282Y e os níveis de ferritina sérica.Material e métodos: Foram convidados 11 pacientes diagnosticados com PCT no ambulatório de dermatologia do HUPE mediante TCLE e coletados urina e sangue para determinação bioquímica de uroporfirinas e níveis de ferro/ferritina sérica respectivamente. A amostra de sangue também foi utilizada para detecção das mutações H63D, S65C e C282Y por PCR tempo real e sequenciamento.Resultados e comentários: Em oito (72%) pacientes do estudo observamos elevada ferritina sérica, sendo seis pacientes carreadores de pelo menos um alelo da mutação D63 (54%), cinco pacientes heterozigotos (45%) e um homozigoto (9%). Não foi observada a presença das mutações S65C e C282Y em nenhum dos pacientes. Mutações do gene HFE1 tem se mostrado pertinentes ao prognóstico da PCT em diversos estudos internacionais. Entretanto, não foi possível determinar a mesma importância neste trabalho, provavelmente, devido ao reduzido número de pacientes. Contudo, o estudo demonstra que adinâmica das mutações do gene HFE1 e sua relevância na população do Rio de Janeiro diferem de outras populações acometidas pela PCT.Palavras-chave: ferritina, gene HFE1, mutações C282Y e H63D, porfiria cutánea tardía (AU)

The Porphyria Cutanea Tarda (PCT) is a disease that generates photosensitivity by the accumulation of porphyries due to the metabolism of the overload of iron amount. The consequences of such mistake can be biochemically observed through the urinary porphyries, serum ferritine, among other parameters. Mutations in the gene HFE1 have been associated not only to the prognosis, but also to the development of the PCT. In this study we had analyzed in 11 patients, assisted at the dermatological outpatient clinic of the Hospital Universitário Pedro Ernestro (HUPE), the genotypes of the geneHFE1 to the mutations H63D, S65C, and C28y, as well as the levels of serum ferritine. Material and methods: We performed our study in 11 patients diagnosed with PCT at the dermatological outpatient clinic at the HUPE, who have agreed to the Terms of Consent (TC) for the study. It had been collected both urine and blood samples to the biochemical analysis of urine-porphyries, as well as the levels of iron/serum ferritine respectively. The blood sample had also been utilized to detect mutations H63D, S65C, and C282Y by PCR in real timing, and sequencing. Results and comments: It had been observed in eight patients a high level of serum ferrite (72%); six patients had been identified as carriers of at least one focus of the mutation D63 (54%): five were heterozygous patients (45%); and one homozygous patient (9%). It had not been observed the presence of mutations S65C, and C282Y in any of the patients. Mutations of the gene HFE1 have been noticed relevant to the prognosis of the PCT in various international studies. Nevertheless, it has not been possible to determine the same relevance on our study probably due to the reduced number of patients. However, this study shows that the dynamics of the gene mutations HFE1 and its relevance in the population of shows differences among populations from other places affected by the PCT (AU)

Effect of age at disease onset in the clinical profile of spondyloarthritis: a study of 1424 Brazilian patients.

OBJECTIVES: To analyse demographic and clinical variables in patients with disease onset before and after 40, 45 and 50 years in a large series of Brazilian SpA patients. METHODS: A common protocol of investigation was prospectively applied to 1424 SpA patients in 29 centres distributed through the main geographical regions in Brazil. The mean age at disease onset was 28.56 ± 12.34 years, with 259 patients (18.2%) referring disease onset after 40 years, 151 (10.6%) after 45 years and 81 (5.8%) after 50 years. Clinical and demographic variables and disease indices (BASDAI, BASFI, BASRI, MASES, ASQoL) were investigated. Ankylosing spondylitis was the most frequent disease (66.3%), followed by psoriatic arthritis (18%), undifferentiated SpA (6.7%), reactive arthritis (5.5%), and enteropathic arthritis (3.5%). RESULTS: Comparing the groups according to age of disease onset, those patients with later onset presented statistical association with female gender, peripheral arthritis, dactylitis, nail involvement and psoriasis, as well as negative statistical association with inflammatory low back pain, alternating buttock pain, radiographic sacroiliitis, hip involvement, positive familial history, HLA-B27 and uveitis. BASDAI, BASFI and quality of life, as well as physicians and patient's global assessment, were similar in all the groups. Radiographic indices showed worse results in the younger age groups. CONCLUSIONS: There are two different clinical patterns in SpA defined by age at disease onset: one with predominance of axial symptoms in the group with disease onset ≤ 40 years and another favouring the peripheral manifestations in those with later disease onset.

Push-out strength of root fillings with or without thermomechanical compaction.

AIM: To evaluate the influence of thermomechanical compaction (Tagger's hybrid technique - THT) on the push-out strength of several root filling materials to root dentine. METHODOLOGY: Root canals of eighty roots in human canines were prepared with the ProTaper system and filled with one of the following materials, using either lateral compaction (LC) (n = 40) or THT (n = 40): AH Plus/gutta-percha (GP) (n = 10), Sealer 26/GP (n = 10), Epiphany SE/Resilon (n = 10) and Epiphany SE/GP (n = 10). Three 2-mm-thick dentine slices were obtained from each third of each root. The root filling in the first slice was subjected to a push-out test to evaluate the bond strength of the materials to intraradicular dentine. Data (in MPa) were analysed using anova and post hoc Tukey's test (P < 0.05). Failure mode was determined at × 25 magnification. The other two slices were prepared for scanning electron microscopy (SEM) to examine the surface of the filling materials. RESULTS: Lateral compaction (1.34 ± 1.14 MPa) was associated with a significantly higher bond strength (P < 0.05) than the THT (0.97 ± 0.88 MPa). AH Plus/GP (2.23 ± 0.83 MPa) and Sealer 26/GP (1.86 ± 0.50 MPa) had significantly higher bond strengths than the other materials and differed significantly from each other (P < 0.05). There was a significant difference (P < 0.05) between the coronal (1.36 ± 1.15 MPa), middle (1.14 ± 1.05 MPa) and apical thirds (0.95 ± 0.83 MPa). Considering the technique and root filling material interaction, AH Plus/GP-LC was associated with the highest mean values (2.65 ± 0.66 MPa) (P < 0.05). Sealer 26/GP-LC (2.10 ± 0.46 MPa), AH Plus/GP-THT (1.81 ± 0.78 MPa) and Sealer 26/GP-TH (1.63 ± 0.44 MPa) had intermediate values that were not significantly different from each other (P > 0.05). Epiphany SE was associated with the lowest mean values (3.70 ± 0.86 MPa) (P < 0.05), regardless of the root filling technique and type of solid material (cone). Adhesive failures predominated in the specimens filled with Epiphany SE, whilst mixed and cohesive failures were more frequent in those filled with AH Plus and Sealer 26, regardless of the root filling technique. SEM analysis revealed that LC produced a dense and well-compacted filling whilst the use of a hybrid thermomechanical technique resulted in the solid material (GP or Resilon) intermingled within sealer to form a nonhomogenous mass. CONCLUSION: Lateral compaction was associated with higher bond strengths of the materials to intraradicular dentine than a hybrid technique using thermomechanical compaction. The greatest push-out strengths were obtained when the canals were filled with LC of AH Plus and GP cones.

Treatment of chronic mandibular dislocations using a new miniplate.

Temporomandibular joint (TMJ) dislocation is defined as an excessive forward movement of the condyle beyond the articular eminence with complete separation of the articular surfaces and fixation in that position. The aim of this study was to describe a modified miniplate designed for treating chronic mandibular dislocations and evaluate the results of its placement in one patient, who was followed for 18 months. The treatment of chronic mandibular dislocation using this modified miniplate was shown to be efficient in relation to the postoperative maximal mouth opening, recurrence and articular function.

Characterization of the biocompatible magnetic colloid on the basis of Fe3O4 nanoparticles coated with dextran, used as contrast agent in magnetic resonance imaging.

The magnetic resonance imaging contrast agent, the so-called Endorem colloidal suspension on the basis of superparamagnetic iron oxide nanoparticles (mean diameter of 5.5 nm) coated with dextran, were characterized on the basis of several measurement techniques to determine the parameters of their most important physical and chemical properties. It is assumed that each nanoparticle is consisted of Fe3O4 monodomain and it was observed that its oxidation to gamma-Fe2O3 occurs at 253.1 degrees C. The Mössbauer spectroscopy have shown a superparamagnetic behavior of the magnetic nanoparticles. The Magnetic Resonance results show an increase of the relaxation times T1, T2, and T2* with decreasing concentration of iron oxide nanoparticles. The relaxation effects of SPIONs contrast agents are influenced by their local concentration as well as the applied field strength and the environment in which these agents interact with surrounding protons. The proton relaxation rates presented a linear behavior with concentration. The measured values of thermo-optic coefficient dn/dT, thermal conductivity kappa, optical birefringence delta n0, nonlinear refractive index n2, nonlinear absorption beta' and third-order nonlinear susceptibility |chi(3)| are also reported.

Characterization of superparamagnetic iron oxide coated with silicone used as contrast agent for magnetic resonance image for the gastrointestinal tract.

The present work is a report of the characterization of superparamagnetic iron oxide nanoparticles coated with silicone used as a contrast agent in magnetic resonance imaging of the gastrointestinal tract. The hydrodynamic size of the contrast agent is 281.2 nm, where it was determined by transmission electron microscopy and a Fe3O4 crystalline structure was identified by X-ray diffraction, also confirmed by Mössbauer Spectroscopy. The blocking temperature of 190 K was determined from magnetic measurements based on the Zero Field Cooled and Field Cooled methods. The hysteresis loops were measured at different temperatures below and above the blocking temperature. Ferromagnetic resonance analysis indicated the superparamagnetic nature of the nanoparticles and a strong temperature dependence of the peak-to-peak linewidth deltaH(pp), giromagnetic factor g, number of spins N(s) and relaxation time T2 were observed. This behavior can be attributed to an increase in the superexchange interaction.