Mechanical competence of ovariectomy-induced compromised bone after single or combined treatment with high-frequency loading and bisphosphonates

Osteoporosis leads to increased bone fragility, thus effective approaches enhancing bone strength are needed. Hence, this study investigated the effect of single or combined application of high-frequency (HF) loading through whole body vibration (WBV) and alendronate (ALN) on the mechanical competence of ovariectomy-induced osteoporotic bone. Thirty-four female Wistar rats were ovariectomized (OVX) or sham-operated (shOVX) and divided into five groups: shOVX, OVX-shWBV, OVX-WBV, ALN-shWBV and ALN-WBV. (Sham)WBV loading was applied for 10 min/day (130 to 150 Hz at 0.3g) for 14 days and ALN at 2 mg/kg/dose was administered 3x/week. Finite element analysis based on micro-CT was employed to assess bone biomechanical properties, relative to bone micro-structural parameters. HF loading application to OVX resulted in an enlarged cortex, but it was not able to improve the biomechanical properties. ALN prevented trabecular bone deterioration and increased bone stiffness and bone strength of OVX bone. Finally, the combination of ALN with HF resulted in an increased cortical thickness in OVX rats when compared to single treatments. Compared to HF loading, ALN treatment is preferred for improving the compromised mechanical competence of OVX bone. In addition, the association of ALN with HF loading results in an additive effect on the cortical thickness

Electron paramagnetic resonance signature of point defects in neutron-irradiated hexagonal boron nitride

© 2018 American Physical Society. Hexagonal boron nitride (h-BN) is an attractive van der Waals material for studying fluorescent defects due to its large band gap. In this work, we demonstrate enhanced pink color due to neutron irradiation and perform electron paramagnetic resonance (EPR) measurements. The point defects are tentatively assigned to doubly occupied nitrogen vacancies with (S=1) and a zero-field splitting (D=1.2GHz). These defects are associated with a broad visible optical absorption band and a near-infrared photoluminescence band centered at ∼490 and 820 nm, respectively. The EPR signal intensities are strongly affected by thermal treatments in the temperature range between 600 °C and 800 °C, where also the irradiation-induced pink color is lost. Our results are important for understanding of point defects in h-BN and their deployment for quantum and integrated photonic applications

The infectivity of SfMNPV on fall armyworm is influenced by the host plant.

This work evaluated the infectivity and production of occlusion bodies (OBs) of the SfMNPV-6NR on fall armyworm (FAW), Spodoptera frugiperda, when fed on different host plants. The experiment was performed in laboratory, in a completely randomized design using two concentrations of SfMNPV-6NR (2×106 and 2×107 OBs/mL) and six different host plants (soybean, corn, cotton, bean, sorghum and millet). The larval mortality, larval weight (LW), pupal weight (PW) of S. frugiperda and the production of OBs by virus were evaluated. S. frugiperda larvae were less susceptible to baculovirus when fed on cotton leaves (38 ± 4.17 and 70 ± 6.44% mortality) in the two concentrations tested (2×106 and 2×107 OBs/mL, respectively). The LW was affected by the virus concentration depending on the plant species consumed and the virus concentrations. The PW was affected by the plant species used to feed larvae. There was no effect of the host plant on the OBs virus production. The results demonstrate adverse effects of the host plant on the infectivity of the SfMNPV-6NR in S. frugiperda, especially a deleterious effect of the cotton plant in the virus infection capacity

Role of microbial biofilms in the maintenance of oral health and in the development of dental caries and periodontal diseases. Consensus report of group 1 of the Joint EFP/ORCA workshop on the boundaries between caries and periodontal disease.

BACKGROUND AND AIMS: The scope of this working group was to review (1) ecological interactions at the dental biofilm in health and disease, (2) the role of microbial communities in the pathogenesis of periodontitis and caries, and (3) the innate host response in caries and periodontal diseases. RESULTS AND CONCLUSIONS: A health-associated biofilm includes genera such as Neisseria, Streptococcus, Actinomyces, Veillonella and Granulicatella. Microorganisms associated with both caries and periodontal diseases are metabolically highly specialized and organized as multispecies microbial biofilms. Progression of these diseases involves multiple microbial interactions driven by different stressors. In caries, the exposure of dental biofilms to dietary sugars and their fermentation to organic acids results in increasing proportions of acidogenic and aciduric species. In gingivitis, plaque accumulation at the gingival margin leads to inflammation and increasing proportions of proteolytic and often obligately anaerobic species. The natural mucosal barriers and saliva are the main innate defence mechanisms against soft tissue bacterial invasion. Similarly, enamel and dentin are important hard tissue barriers to the caries process. Given that the present state of knowledge suggests that the aetiologies of caries and periodontal diseases are mutually independent, the elements of innate immunity that appear to contribute to resistance to both are somewhat coincidental

Levantamento da incidência de dentes extranumerários na dentição permanente, através de radiografias panorâmicas

A espécie humana apresenta um número constante de dentes nas arcadas, tanto na dentição decídua quanto na permanente. Os dentes formados em excesso, ou seja, os que excedem os 20 elementos decíduos ou os 32 elementos permanentes normais são chamados de extranumerários (RIOS et al., 2002). O objetivo do presente trabalho foi o de gerar maiores informações a respeito da incidência de dentes extranumerários na população de Volta Redonda, bem como aperfeiçoar o reconhecimento de tais alterações pelos alunos de graduação do curso de Odontologia do UniFOA. Para tal foram avaliadas 2000 radiografias panorâmicas pertencentes ao acervo da Disciplina de Patologia Bucal do Curso de Odontologia do UniFOA, em relação a presença de imagens compatíveis com dentes extranumerários. As radiografias foram inicialmente examinadas pelos alunos participantes, e posteriormente conferidas pelos professores orientadores. Foram encontrados 37 (1,85%) pacientes portadores de dentes extranumerários, sendo 20 (54%) do gênero masculino e 17 (46%) do feminino. A idade variou de 7 a 38 anos, com média de 18,7 anos. Dos 37 pacientes, 24 (64,9%) apresentaram um único dente extranumerário, 13 (35,1%) apresentaram 2 elementos extranumerários, totalizando 50 dentes. Não foram encontrados pacientes com 3 ou mais elementos nessa amostra. A incidência encontrada em Volta Redonda foi de 1,85%, semelhante ao relatado na literatura. A avaliação de um número grande de radiografias panorâmicas permitiu aos alunos participantes melhor discernimento no que se refere às imagens compatíveis com dentes extranumerários

Biossolubilização de potássio por microrganismos in vitro a partir de rocha verdete.

FertBio 2016