Environmental assessment and durability performance of cement mortar incorporating sugarcane vinasse in replacement of water.

Sugarcane vinasse wastewater (SVW) is one of the most voluminous waste generated in the ethanol industry and usually applied in fertigation. It is characterized by presenting high COD and BOD; thus, continued disposal of vinasse results in negative environmental impacts. In this paper, we investigated the potential of SVW in replacement of water in mortar, rethinking about reuse of effluent, reduction of pollutants in the environment, and water consumption in civil construction. Mortar composites with 0, 20, 40, 60, 80, and 100% of water replaced by SVW were studied in order to determine the optimum content. Mortars with 60 to 100% of SVW result in improved workability and reduction in water demand. The mortars with 20, 40, and 60% SVW resulted in satisfactory mechanical properties, i.e., similar to the control mortar. However, XRD analysis of cement pastes showed that the SVW causes a delay in CH formation, reaching mechanical strength after 28 days. Durability tests results showed that SVW contributes to the mortar becoming more impermeable; therefore, less susceptible to weathering. This study provides an important evaluation of the potential of SVW for application in civil construction, indicating relevant results for replacement of water by liquid wastes in cementitious composites and reduction the use of natural resources.

Electron Spin Resonance Dosimetry Studies of Irradiated Sulfite Salts.

The study of new materials for radiation dosimetry is important to improve the present state of the art and to help in cases of accidents for retrospective dosimetry. Sulfites are compounds that contain a sulfur ion, widely used in the food industry. Due to the significant application of these compounds, sulfites are interesting candidates for accidental dosimetry, as fortuitous radiation detectors. The presence of the SO3- anion enables its detection by electron spin resonance (ESR) spectroscopy. The Dose-Response behavior, signal stability and other spectral features were investigated for sodium sulfite, sodium bisulfite, sodium metabisulfite and potassium metabisulfite, all in crystalline forms. The ESR spectrum of salts presented stability and proportional response with dose, presenting potential for dosimetry applications.

Influence of silver nanoparticles on the tissue reaction of polyacrylic acid-based gel.

PURPOSE: To study the influence of silver nanoparticles (AgNP) on tissue reaction when incorporated into a polymeric matrix of polyacrylic acid-based (Carbopol®) gel as a proposal for a new low-cost type of biomaterial that is simple to manufacture for use as an antimicrobial and antioxidative dressing. METHODS: In-vivo tests of implantation in the subcutaneous tissue of the back of rats were performed using polyethylene tubes in three situations: empty, only the gel, and gel incorporated with AgNP. Then, the tissue reaction was studied by counting inflammatory cells. Additionally, in-vitro tests of the antioxidative and antimicrobial activity of AgNP were performed. The radical 2,2 diphenyl-1 picrylhydrazyl (DPPH) was used to test the antioxidative activity of AgNP using electron spin resonance. The antimicrobial activity of AgNP was determined by minimum inhibitory concentration against the microorganisms: Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. RESULTS: The results indicated that AgNP presents antioxidative activity and was able to inhibit the growth of the microorganisms tested. The addition of AgNP in Carbopol® did not alter the tissue inflammatory response (p>0.05, Kruskal-Wallis's test). CONCLUSIONS: The new biomaterial is promising for future use as a dressing for its beneficial properties for regenerative processes.

Effect of the cranberry ( Vaccinium macrocarpon ) juice on reducing dentin erosion: an in vitro study.

Vaccinium macrocarpon (cranberry) is a fruit that has an inhibitory effect on matrix metalloproteinases (MMPs) present in dentin and saliva. The inhibition of MMPs has been shown to prevent dentin erosion. The aim of this study was to analyze the effect of cranberry juice on the reduction of dentin erosion in vitro. Specimens of bovine dentin (4×4×2 mm) were randomized and divided into 4 groups (n = 17/group): distilled water (C-control, pH 7.2); green tea extract solution containing 400 µm epigallo-catechin-gallate (EGCg, positive control, pH 4.5); 10% cranberry extract (CrE, pH 3.9), and cranberry juice (CrJ, Cranberry JuxxTM, pH 2.8). Specimens were submitted to erosive pH cycles for 5 days. Each day, four demineralizations were carried out with 0.1% citric acid (90 s). After the acid challenges, specimens were rinsed and kept in treatment solutions for 1 min; afterwards, they were rinsed and stored in artificial saliva for 1 h at 37°C (or overnight at the end of each day). After the experimental period of 5 days, dentin loss was evaluated by contact profilometry. Data were analyzed by ANOVA and Tukey's test (p < 0.05). Dentin loss (µm ± SD) was significantly lower for all treatments (EGCg = 9.93 ± 2.90; CrE = 12.10 ± 5.44; CrJ = 11.04 ± 5.70) compared to control (21.23 ± 11.96), but it did not significantly differ from each other. These results indicate that the commercial cranberry juice, despite its low pH, is able to reduce dentin erosion, which might be due to the ability of cranberry components to inhibit MMPs.

ESR dosimetry with lithium, potassium, and sodium compounds.

This work consists of a first investigation of materials that could be used as ESR dosimeters with doses up to 5 Gy aiming possible applications that would include retrospective dosimetry or dosimetry in specific applications. The characteristics considered were radiological properties close to that of soft tissues, evaluated through their effective atomic number and mass attenuation coefficient, ESR signal dependence on the irradiation dose, sensitivity to dose in the range of ∼5 Gy when exposed to a 50 kV x-ray source and signal stability over a 30-day period. A total of 16 compounds of lithium, potassium and sodium were analyzed, including the already known dosimeter material, lithium formate. Among them, lithium carbonate, lithium phosphate, sodium formate, sodium acetate, sodium citrate, sodium dithionite, sodium carbonate, showed eligible characteristics. After analyzing the ESR dose-response curves, the molecules that showed greater sensitivity to radiation in descending order are: sodium formate, sodium acetate, sodium citrate and sodium dithionite, however, lower than lithium formate. Sodium formate and sodium citrate presented ESR signals with high stability, similar to lithium formate, with fading of ∼3% in 30 days, different from sodium acetate, which showed a 19% reduction. Sodium citrate also presents radiological properties close to soft tissue. Therefore, considering all properties, in the set of the new materials studied in this work, sodium citrate is a promising material for ESR dosimetry.

Effect of the cranberry ( Vaccinium macrocarpon ) juice on reducing dentin erosion: an in vitro study

Abstract Vaccinium macrocarpon (cranberry) is a fruit that has an inhibitory effect on matrix metalloproteinases (MMPs) present in dentin and saliva. The inhibition of MMPs has been shown to prevent dentin erosion. The aim of this study was to analyze the effect of cranberry juice on the reduction of dentin erosion in vitro. Specimens of bovine dentin (4×4×2 mm) were randomized and divided into 4 groups (n = 17/group): distilled water (C-control, pH 7.2); green tea extract solution containing 400 µm epigallo-catechin-gallate (EGCg, positive control, pH 4.5); 10% cranberry extract (CrE, pH 3.9), and cranberry juice (CrJ, Cranberry JuxxTM, pH 2.8). Specimens were submitted to erosive pH cycles for 5 days. Each day, four demineralizations were carried out with 0.1% citric acid (90 s). After the acid challenges, specimens were rinsed and kept in treatment solutions for 1 min; afterwards, they were rinsed and stored in artificial saliva for 1 h at 37°C (or overnight at the end of each day). After the experimental period of 5 days, dentin loss was evaluated by contact profilometry. Data were analyzed by ANOVA and Tukey's test (p < 0.05). Dentin loss (µm ± SD) was significantly lower for all treatments (EGCg = 9.93 ± 2.90; CrE = 12.10 ± 5.44; CrJ = 11.04 ± 5.70) compared to control (21.23 ± 11.96), but it did not significantly differ from each other. These results indicate that the commercial cranberry juice, despite its low pH, is able to reduce dentin erosion, which might be due to the ability of cranberry components to inhibit MMPs.

Tissue reaction and anti-biofilm action of new biomaterial composed of latex from Hancornia speciosa Gomes and silver nanoparticles.

In this work, the natural latex extracted from Harconia speciosa was incorporated with silver nanoparticles (AgNP) to compose a functional biomaterial associating the intrinsic angiogenic activity of the latex and the antimicrobial activity of AgNP. Tissue reaction after subcutaneous implantation in dorsum of rats of membranes without AgNP and with 0.05%, 0.4% AgNP was compared at 3, 7 and 25 days. No statistically significant difference in the tissue response of the different biomaterials was observed, indicating that AgNP did not interfere with the inflammatory reaction (p > 0.05) or with the angiogenic activity of latex. Biomembranes were also tested against bacterial biofilm formation by Staphylococcus aureus and the antimicrobial activity of the new biomaterial can be found with bacteria crenation (0.05% AgNP) and no biofilm deposition (0.4% AgNP). Therefore, this biomaterial has interesting properties for the tissue repair process and may be feasible for future applications as dressing.

Detection of rare-earth elements using fiddler crabs Leptuca leptodactyla (Crustacea: Ocypodidae) as bioindicators in mangroves on the coast of São Paulo, Brazil.

Rare-earth elements have gained significant attention as they are currently widely used in high tech, chemical, and pharmaceutical industries. Here we used the fiddler crabs Leptuca leptodactyla as bioindicators to verify the presence of rare-earth elements in two mangrove areas of the Ubatuba, northern littoral of São Paulo state, Brazil. The specimens were collected in the mangrove areas of the Tavares River and Quiririm-Puruba river system, separated by season (dry and rainy). A total of 243 individuals were collected and analyzed. For determination and quantification of the elements we used the instrumental neutron activation analysis (INAA) technique. In both the dry and rainy season, the elements La, Ce, Sm, Eu, Tb, Yb and Sc were detected in samples of both mangroves, with La and Ce presenting higher concentrations. Samples from Tavares River mangrove had higher concentration levels of rare-earth elements than those of the Quiririm-Puruba river system. That is probably due to the central geographic position of the Tavares River in Ubatuba, which crosses a large portion of the city and receives a great amount of sewage. On the other hand, the Quiririm-Puruba river system has less anthropogenic inputs, thus, it receives much fewer rare-earth elements when compared to the Tavares River.

Xenotransplantation of human dental pulp stem cells in platelet-rich plasma for the treatment of full-thickness articular cartilage defects in a rabbit model.

Stem cells in platelet-rich plasma (PRP) scaffolds may be a promising treatment for cartilage repair. Human dental pulp stem cell (hDPSC) subpopulations have been identified to have substantial angiogenic, neurogenic and regenerative potential when compared with other stem cell sources. The present study evaluated the potential of hDPSCs in a PRP scaffold to regenerate full-thickness cartilage defects in rabbits. Full-thickness articular cartilage defects were created in the patellar groove of the femur of 30 rabbits allocated into three experimental groups: Those with an untreated critical defect (CTL), those treated with PRP (PRP) and those treated with stem cells in a PRP scaffold (PRP+SC). The patellar grooves of the femurs from the experimental groups were evaluated macroscopically and histologically at 6 and 12 weeks post-surgery. The synovial membranes were also collected and evaluated for histopathological analysis. The synovial lining cell layer was enlarged in the CTL group compared with the PRP group at 6 weeks (P=0.037) but not with the PRP+SC group. All groups exhibited low-grade synovitis at 6 weeks and no synovitis at 12 weeks. Notably, macroscopic grades for the area of articular cartilage repair for the PRP+SC group were significantly improved compared with those in the CTL (P=0.001) and PRP (P=0.049) groups at 12 weeks. Furthermore, histological scores (modified O'Driscoll scoring system) of the patellar groove articular cartilage in the PRP+SC and PRP groups, in which the articular cartilage was primarily hyaline-like, were significantly higher compared with those in the CTL group at 12 weeks (P=0.002 and P=0.007, respectively). The present results support the therapeutic use of hDPSCs for the treatment of full-thickness articular cartilage defects.

Toxicity of silver nanoparticles released by Hancornia speciosa (Mangabeira) biomembrane.

Recent research has shown that latex from different species is able to produce tissue replacement and regeneration. Particularly, biomembranes obtained from Hancornia speciosa latex (HSB) have shown high angiogenic and osteogenic activity. Considering new materials for wound healing, it would be interesting to develop a product combining antibacterial and antifungal activities. Silver nanoparticles (AgNP) have been commonly used for this purpose in medicinal products and devices for decades. In order to combine angiogenic, antibacterial and antifungal properties on the same platform, we developed an HSB containing 3 concentrations of AgNP. It was observed that the HSB successfully accommodated the AgNP in the matrix and released them in a controlled way. The release dynamics of AgNP by HSB was described by UV-vis absorption spectroscopy. The released nanoparticles were evaluated by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) measurements. In addition, the cytotoxic and genotoxic effects were evaluated using the Allium cepa assay. The results showed no cytotoxic effect of HSB-AgNP in all studied concentrations. The genotoxic effect was observed in HSB-AgNP at the two highest concentrations, however not at the lowest concentration. Thus, the addition of AgNP at the lowest concentration can improve the pharmacological activity of HSB without causing a toxic effect on vegetal cells. Therefore, the H. speciosa latex biomembrane presented in this paper combines angiogenic, anti-inflammatory and antibacterial properties and can be considered potentially new biomaterial for wound-healing.

Tissue reaction after subcutaneous implants of a new material composed of ethylene-vinyl acetate and starch for future use as a biomaterial.

This study aimed to evaluate the tissue reaction of ethylene-vinyl acetate (EVA) in 4 different compositions and processing: EVA foamed at high pressure with ultrasound (EVACU); EVA with 15% starch foamed at high pressure with ultrasound (EVAMCU); EVA with 15% starch foamed at high pressure without ultrasound and EVA foamed at high pressure without ultrasound as future use as a porous scaffold. Scanning electron microscopy images showed the influence of starch, reducing the diameter of pores. The number of open pores was also reduced with the addition of starch. The ultrasound applied during the manufacturing of composites does not affect these characteristics. Eighteen rats were used to test the tissue reaction of materials and PTFE (polytetrafluoroethylene), proven biocompatible material. After 7, 15, and 60 days of surgery, the materials were removed and processed for microscopic evaluation and counting of the inflammatory infiltrate. The data shows inflammatory reaction similar to PTFE. However, in the quantitative analysis at 60 days, the EVACU and EVAMCU showed less quantity of mononuclear cells (p < 0.05). Thus, the results suggest that the use of ultrasound in the production method (EVA) seems to have improved cell behavior regarding the reduction of infiltration over the period, with tissue response equivalent to the PTFE. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 400-407, 2019.

Application of botulinum toxin type A in gummy smile: case report / Aplicação da toxina botulínica tipo A em sorriso gengival: relato de caso

ABSTRACT Gummy smile is one of the major complaints of patients, due to its influence on the self-esteem. It is known that it has a multifactorial cause and can be present in the excessive vertical growth of the maxilla, excessive labial contraction, short upper lip and extrusion of the anterior teeth. The use of the botulinum toxin can be associated with additional treatments or be applied individually, according to the need of each patient. The goal of this research study was to present a clinical case using botulinum toxin type A as an alternative therapy to correct the gummy smile. A 22-year-old patient, presenting vertical maxillary growth, reporting aesthetic discomfort while smiling, chose for an alternative treatment therapy with the application of botulinum toxin to correct the accentuated gingival display. The results show that the toxin is a satisfactory treatment option and its indication is considered a fast, effective, easy and safe treatment method, being a more conservative approach compared to surgical procedures.

RESUMO O sorriso gengival, é uma das grandes queixas dos pacientes, devido a sua influência na auto estima do mesmo. Sua causa é multifatorial, podendo estar presente no excesso de crescimento vertical da maxila, contração labial excessiva, lábio superior curto e extrusão dos dentes anteriores. A aplicação da toxina botulínica pode ser associada a outros tratamentos ou isoladamente, de acordo com a necessidade de cada paciente. O objetivo desse trabalho foi apresentar um caso clinico utilizando a toxina botulínica tipo A como uma alternativa terapêutica para a correção do sorriso gengival. Paciente, 22 anos, apresentando crescimento vertical da maxila, relatando desconforto estético ao sorrir, optou pela alternativa terapêutica, com a aplicação da toxina botulínica para correção da exposição gengival acentuada. Os resultados encontrados mostram que a toxina é um tratamento satisfatório e sua indicação é considerada um tratamento rápido, eficaz, fácil e seguro. Um método mais conservador quando comparado aos procedimentos cirúrgicos.

Electron spin resonance (ESR) dose measurement in bone of Hiroshima A-bomb victim.

Explosion of the bombs in Hiroshima and Nagasaki corresponds to the only historical moment when atomic bombs were used against civilians. This event triggered countless investigations into the effects and dosimetry of ionizing radiation. However, none of the investigations has used the victims' bones as dosimeter. Here, we assess samples of bones obtained from fatal victims of the explosion by Electron Spin Resonance (ESR). In 1973, one of the authors of the present study (SM) traveled to Japan and conducted a preliminary experiment on the victims' bone samples. The idea was to use the paramagnetism induced in bone after irradiation to measure the radiation dose. Technological advances involved in the construction of spectrometers, better knowledge of the paramagnetic center, and improvement in signal processing techniques have allowed us to resume the investigation. We obtained a reconstructed dose of 9.46 ± 3.4 Gy from the jawbone, which was compatible with the dose distribution in different locations as measured in non-biological materials such as wall bricks and roof tiles.

A utilização da Ressonância magnética para auxílio do diagnóstico de fraturas por estresse: revisão sistemática / Magnetic resonance imaging in the diagnosis of stress fractures: a systematic review

Introdução: as fraturas por estresse são lesões causadas por fadiga ou insuficiência do osso acometido. Ocorrem após a formação e o acúmulo de micro fraturas nas trabéculas ósseas normais. Objetivo: avaliação das principais potencialidades do uso da Ressonância magnética para auxílio do diagnóstico de fraturas por estresse. Metodologia: 15 artigos foram selecionados nas línguas portuguesa e inglesa indexados nas bases de dados eletrônicos Web of Science, LILACS, SciELO, e Pubmed partindo dos descritores ressonância magnética, fraturas fechadas e diagnóstico, de acordo com os Descritores em Ciências da Saúde (DeCS). Resultado: foram analisados 68 artigos dos quais 53 artigos foram excluídos por não se enquadrarem nos critérios de seleção e 15 preencheram os critérios de inclusão. Conclusão: a ressonância magnética é o método mais indicado para se diagnosticar as fraturas por estresse, além de ser muito sensível e evidenciar as fraturas precocemente, além de não expor os pacientes à radiação ionizante.

Introduction: Stress fractures are injuries caused by fatigue or insufficiency of the affected bone. They occur after formation and the accumulation of micro fractures in normal bone trabeculae. Objective: to evaluate the main potentialities of magnetic resonance imaging to aid in the diagnosis of stress fractures. Methodology: 15 articles were selected in the Portuguese and English languages indexed in the electronic databases Web of Science, LILACS, SciELO, and Pubmed starting from the descriptors magnetic resonance, closed fractures and diagnosis, according to the Descriptors in Health Sciences (DeCS). Results: We analyzed 68 articles in which 53 articles were excluded because they did not fit the selection criteria and 15 met the inclusion criteria. Conclusion: magnetic resonance imaging the most appropriate method to diagnose stress fractures, as well as being very sensitive and showing fractures early, and not exposing patients to ionizing radiation.

Biomateriais utilizados na artroplastia parcial ou total da articulação temporomandibular: uma revisão de literatura / Biomaterials used in partial or total temporomandibular joint arthroplasty: a review of the literature

Introdução: as disfunções da articulação temporomandibular constituem uma variedade de doenças que compreendem disfunções nos músculos da mastigação, nas estruturas articulares ou em ambos. Em alguns casos a melhora da disfunção pode decorrer apenas de tratamento clínico conservador, porém, quando os resultados não são favoráveis, o tratamento cirúrgico deve ser considerado. A reconstrução articular parcial ou total é uma das formas de tratamento cirúrgico disponível. Objetivo: objetivo deste trabalho foi realizar uma revisão bibliográfica sobre os principais biomateriais disponíveis para a reconstrução da articulação temporomandibular. Método: o trabalho foi realizado na base de dados da Pubmed, Scielo e Periódicos Capes. Os descritores empregados foram: artoplastia temporomandibular, prótese articular, disfunção temporomandibular. As referências foram avaliadas quanto à relevância correlacionadas ao tema proposto. Foram selecionados os artigos em português e inglês, publicados no período de Janeiro 1971 a outubro de 2017. Considerações finais: existe a recomendação de haver uma continuidade de esforços para melhorar o material aloplástico para que os resultados obtidos com essa técnica se tornem o tratamento padrão para a DTM severa, contudo é importante não se esquecer de esgotar as modalidades terapêuticas conservadoras antes de se prosseguir para qualquer tipo de cirurgia. Nos casos onde uma prótese articular total é indicada, que os princípios biomecânicos sejam respeitados e que estudos clínicos metodologicamente adequados sejam realizados para fundamentarem esta condição de maneira referendada para a substituição aloplástica da ATM.

Introduction: temporomandibular joint dysfunctions are a variety of diseases that include dysfunctions in masticatory muscles, joint structures, or both. In some cases the improvement of the dysfunction may only result from conservative clinical treatment, however, when the results are not favorable the surgical treatment should be considered. Partial or total joint reconstruction is one of the forms of surgical treatment available. Objective: the objective of this work was to perform a bibliographic review on the main biomaterials available for the reconstruction of the temporomandibular joint. Method: work was carried out in the database of Pubmed, Scielo and Capes Periodicals. The descriptors employed were: temporomandibular arthroplasty, joint prosthesis, temporomandibular dysfunction. The references were evaluated regarding the relevance correlated to the proposed theme. The articles in Portuguese and English, published between January 1971 and October 2017, were selected. Final remarks: there is a recommendation for continuity of efforts to improve the alloplastic material so that the results obtained with this technique become the treatment standard for severe TMD, but it is important to remember to exhaust the conservative therapeutic modalities before proceeding for any type of surgery. In cases where a total joint prosthesis is indicated, biomechanical principles are respected and methodologically adequate clinical studies are performed to support this condition in a manner recommended for the alloplastic replacement of TMJ.

Biomateriais utilizados em artroplastia de quadril / Biomaterials used in hip arthroplasty

Introdução: a artroplastia de quadril é um procedimento cirúrgico utilizado com frequência na recuperação do quadril lesado, sendo necessário a utilização de biomateriais na confecção das próteses que farão a nova função dessa articulação. Os biomateriais mais frequentemente utilizados em reconstruções de quadril podem ser agrupados em: metálicos, poliméricos, cerâmicos e compósitos. Objetivo: discorrer sobre tipos de biomateriais utilizados nos implantes das artroplastias de quadril, apresentando suas características, vantagens e falhas, descritas na literatura. Método: foi realizado uma revisão da literatura nas bases de dados eletrônicos: PubMED/Medline, Lilacs e Scielo. Conclusão: os materiais utilizados em artroplastia de quadril evoluíram muito nos últimos 20 anos, especialmente considerando a resistência ao desgaste. Porém, não é somente o tipo de material implantado que determina os resultados em artroplastia do quadril. Bons resultados dependem de uma cirurgia bem indicada, bem planejada, bem realizada e do uso de material adequado.

Introduction: hip arthroplasty is a surgical procedure frequently used in the recovery of the injured hip, and it is necessary to use biomaterials in the preparation of prostheses that will perform a new function of this joint. The biomaterials most used in hip reconstructions can be grouped into metallic, polymeric, ceramic and composite. Objective: to describe the types of biomaterials used in hip arthroplasty implants, presenting their characteristics, advantages and failures, descriptions in the literature. Method: a literature review was performed in the electronic databases: PubMED / Medline, Lilacs and Scielo. Conclusion: the materials used in hip arthroplasty have evolved a lot in the last 20 years, considering the resistance to wear. However, it is not the type of implanted material that determines the results in hip arthroplasty. Good results depend on well-indicated, well-planned, well-performed surgery and use of the right material.

Effect of ovariectomy in bone structure of mandibular condyle.

PURPOSE: To evaluate the bone structure of the mandibular condyle through an animal model, after ovariectomy. METHODS: Thirty-six female Wistar rats were divided into 2 groups. The OVX group was submitted to bilateral ovariectomy, the SHAM group underwent the same surgical treatment, but without removal of the ovaries. After 90, 105 and 135 days after surgery, six animals from each group were submitted to euthanasia and the part containing the condyle was removed. RESULTS: The microscopic analysis shows an increase in marrow spaces over time in the OVX group. The morphometric study shows reduction in the amount of bone tissue in the OVX group 135 days period in comparison with for the initial period (90 days) (p <0.05, ANOVA, Tukey). CONCLUSION: The estrogen deficiency also affects the bone structure of the condyle.

Effect of ovariectomy in bone structure of mandibular condyle

Abstract Purpose: To evaluate the bone structure of the mandibular condyle through an animal model, after ovariectomy. Methods: Thirty-six female Wistar rats were divided into 2 groups. The OVX group was submitted to bilateral ovariectomy, the SHAM group underwent the same surgical treatment, but without removal of the ovaries. After 90, 105 and 135 days after surgery, six animals from each group were submitted to euthanasia and the part containing the condyle was removed. Results: The microscopic analysis shows an increase in marrow spaces over time in the OVX group. The morphometric study shows reduction in the amount of bone tissue in the OVX group 135 days period in comparison with for the initial period (90 days) (p <0.05, ANOVA, Tukey). Conclusion: The estrogen deficiency also affects the bone structure of the condyle.

Contracaecum sp. parasitizing Acestrorhynchus lacustris as a bioindicator for metal pollution in the Batalha River, southeast Brazil.

Pollution in aquatic ecosystems due to negative human activities remains a problem in both freshwater and marine environments and is an ongoing subject of research. Several studies have shown that some fish parasites can be used as a tool for biomonitoring because they demonstrate higher metal accumulation capacity compared to their host tissues. However, compared to acanthocephalans, information regarding the absorption mechanisms and accumulation rates in nematodes is relatively limited. Here, we evaluated the potential of larvae Contracaecum sp. (L3) as indicators of contamination by metals by analyzing thirteen element concentrations: magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), barium (Ba), and lead (Pb) in the parasites and host Acestrorhynchus lacustris, using inductively coupled plasma mass spectrometry. Twelve of the thirteen analyzed elements were detected in at least 2-fold higher concentrations (e.g. Ni) and were up to approximately 50-fold higher (e.g. Pb) in parasites than in host tissues, including elements known for their high toxicity (As, Cd, Pb) and those considered to be essential (Cu and Zn). Our results suggest that Contracaecum sp. larvae can be used as bioindicators of metal contamination because even in early stages of development, numerous essential and non-essential elements were accumulated, making this system a useful tool for monitoring polluted environments.

ESR dating of Smilodon populator from Toca de Cima dos Pilão, Piauí, Brazil.

Smilodon is a genus of big cats that lived from the early to the late Pleistocene in regions extending from North to South America. The fossil records of the "saber-toothed cats" are uneven, with some taxa being quite abundant in certain regions. In Brazil, Smilodon populator is a well-known species whose remains, although scarce in comparison to other large mammals, are found all across the country. In particular, there are multiple records of this species in the region of the Serra da Capivara National Park. This area was home to a rich Pleistocene-Holocene fauna, including many mammals. Here, we report on the Electron Spin Resonance dating of a Smilodon populator tooth found in "Toca de Cima dos Pilão", located in the surroundings of the Serra da Capivara National Park. The equivalent dose found after exponential fitting of dose-response curve was (2.7±0.3)x102Gy. Neutron Activation Analysis was used to determine the concentration of radioisotopes present in the sample and in the sediment to calculate the internal and external dose rates. The result of age found is 93±9ka, which confirmed the presence of this species in Serra da Capivara National Park in the late Pleistocene.