Accuracy of silicone impressions and stone models using two laboratory scanners: a 3D evaluation.

PURPOSE: To evaluate the in vitro accuracy of impressions obtained with two silicone and corresponding stone models using two laboratory scanners. MATERIAL AND METHODS: A master model with synthetic resin teeth with two single-unit crown preparations was created and scanned using a 12-MP scanner. Five conventional impressions of the physical model were prepared with different silicone impression systems (Zhermack and Coltene) using the double-mix technique and poured with gypsum. The impressions and stone models obtained were scanned by two extraoral scanning systems (Identica T500 Medit and S600 ARTI Zirkonzahn). All best-fit superimpositions of the teeth areas were conducted between the master model and the scans of the impressions and models obtained with the two scanners. A P < .05 significance level was considered. RESULTS: The Identica T500 Medit scanner showed an accuracy of 102.34 (89.67, 115.01) µm for Coltene silicone and 79.51 (67.82, 91.21) µm for Zhermack silicone, while the S600 ARTI Zirkonzhan scanner presented 110.79 (98.24, 123.33) µm and 91.91 (81.29, 102.54) µm, respectively, with significant differences between scanners for Zhermack silicone (P = .008) and for the corresponding stone models (P = .002). Zhermack silicone presented overall discrepancies lower than Coltene silicone, with statistically significant differences in both scanners analyzed (P < .001; P = .017). However, the discrepancies found were within clinically acceptable values. With the Zirkonzahn scanner, discrepancies found in the Zhermack impressions were lower than in the corresponding stone models (P < .001). CONCLUSION: The direct digitalization of silicone impressions by laboratory scanners presented comparable results to conventional techniques with stone models.

Proposal of a formula mouth opening reduction assessment, for forensic purposes.

OBJECTIVES: To propose a formula for determining reduced mouth opening due to oral and maxillofacial trauma, based on the normal standard of the Brazilian population. MATERIALS AND METHODS: First, the maximum mouth opening was established, in millimeters, using a digital pachymeter, in patients between 22 and 60 years of age. The opening was measured from the upper to the lower incisor, at maximum amplitude, without pain and overbite. Second, the facial profile type and height were determined. A formula was developed to calculate the percentage of reduced mouth opening based on the normal average. RESULTS: The average mouth opening was found to be 51.71 mm in men and 47.94 mm in women, thus establishing a statistically significant difference in mouth opening between sexes. However, there was no statistically significant difference between age and profile type with mouth opening. The following formulas were developed to calculate the reduced mouth opening, based on the averages found, by using RA= [100-(A.1.93)].0.3 for males and RA= [100-(A.2,08)] .0.3 for female patients. CONCLUSION: Considering that mouth opening tends to be larger in men than in women, valid formulas can be used to determine the correct percentage of reduced mouth opening.

Physically Active Bioreactors for Tissue Engineering Applications.

Tissue engineering (TE) is a strongly expanding research area. TE approaches require biocompatible scaffolds, cells, and different applied stimuli, which altogether mimic the natural tissue microenvironment. Also, the extracellular matrix serves as a structural base for cells and as a source of growth factors and biophysical cues. The 3D characteristics of the microenvironment is one of the most recognized key factors for obtaining specific cell responses in vivo, being the physical cues increasingly investigated. Supporting those advances is the progress of smart and multifunctional materials design, whose properties improve the cell behavior control through the possibility of providing specific chemical and physical stimuli to the cellular environment. In this sense, a varying set of bioreactors that properly stimulate those materials and cells in vitro, creating an appropriate biomimetic microenvironment, is developed to obtain active bioreactors. This review provides a comprehensive overview on the important microenvironments of different cells and tissues, the smart materials type used for providing such microenvironments and the specific bioreactor technologies that allow subjecting the cells/tissues to the required biomimetic biochemical and biophysical cues. Further, it is shown that microfluidic bioreactors represent a growing and interesting field that hold great promise for achieving suitable TE strategies.

Photocatalytic and antimicrobial multifunctional nanocomposite membranes for emerging pollutants water treatment applications.

Emerging pollutants represent a new global problem for water quality. As these compounds get into the environment, they cause severe threats to aquatic environments and human health and are typically resistant to conventional wastewater treatments. In this work, TiO2 nanoparticles surface was functionalized with silver (Ag) nanoparticles, and solvent cast and electrospun membranes of poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) were prepared with different concentrations of TiO2 and Ag-TiO2 to produce a multifunctional material. The photocatalytic activity of the nanocomposites was evaluated through the degradation of norfloxacin under ultraviolet (UV) and visible radiation. It is shown that nanocomposites with Ag-TiO2 show the highest degradation efficiencies: 64.2% under UV and 80.7% under visible radiation, for 90 and 300 min, respectively. Furthermore, the recyclability of the membranes has also been demonstrated. Finally, it is shown the antimicrobial activity of the nanocomposite membranes, demonstrating the suitability of the Ag-TiO2/PVDF-HFP nanocomposites as multifunctional photocatalytic and antimicrobial membranes for water remediation applications.

Avaliação clínica e bioquímica de cães submetidos a dois métodos de hidroterapia / Clinical and biochemical evaluation of dogs submitted to two methods of hydrotherapy

Avaliou-se a resposta dos parâmetros fisiológicos de frequência cardíaca (FC) e respiratória (FR), temperatura retal (TR) e a atividade sérica das enzimas creatina quinase (CK) e lactato desidrogenase (LDH) em cães adultos hígidos, machos e fêmeas, sob duas modalidades de hidroterapia. Dez cães foram distribuídos em dois grupos de cinco animais, denominados de grupo I (caminhada em esteira aquática) e grupo II (natação) e submetidos a duas sessões por semana com duração inicial de 10 minutos, acrescida de cinco minutos por sessão até 30 minutos, durante nove semanas. As avaliações foram realizadas antes, imediatamente depois e quatro horas após o exercício em todas as sessões para as variáveis de FC, FR e TR e nos dias um, sete, 28 e 60 para CK e LDH. Não houve diferença (P>0,05) quando comparados os valores médios dos parâmetros fisiológicos de frequência cardíaca e respiratória e de temperatura retal. Os níveis de CK e LDH não se elevaram após a hidroterapia nos diferentes tempos e dias avaliados. Dessa forma, foi possível concluir que as sessões de natação e de caminhada em esteira aquática não causaram alterações nos parâmetros fisiológicos de frequência cardíaca e respiratória, temperatura retal e nos níveis sanguíneos de creatina quinase (CK) e lactato desidrogenase (LDH) no protocolo proposto.(AU)

The physiological parameters of heart rate (HR), respiratory rate (RR), rectal temperature (TR), and serum activity of creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes were determined in healthy dogs, male and female, under two hydrotherapy modalities. Ten dogs were distributed in two groups of five animals, named Group I (underwater treadmill walk) and Group II (swimming), submitted to two sessions per week with initial duration of 10 minutes, plus 5 minutes per session up to 30 minutes, during 9 weeks. The evaluations were performed before, immediately after and 4 hours after exercise in all sessions for the HR, RR and TR variables and on days one, seven, 28 and 60 for CK and LDH. There was no difference (P> 0.05) when comparing the mean values of physiological parameters of heart and respiratory rate and rectal temperature. CK and LDH levels did not rise after hydrotherapy at different times and days evaluated. So, it was possible to conclude that swimming sessions and underwater treadmill walking did not cause alterations in the physiological parameters of heart and respiratory rate, rectal temperature, and the blood levels of creatine kinase (CK) and lactate dehydrogenase (LDH) in the proposed protocol.(AU)

Biocompounds from rapeseed oil industry co-stream as active ingredients for skin care applications.

OBJECTIVE: Despite the great number of substances produced by the skincare industry, very few of them seem to truly have an effect on the skin. Therefore, given the social implications surrounding physical appearance, the search for new bioactive compounds to prevent or attenuate skin ageing and enhance self-image is a priority of current research. In this context, being rich in valuable compounds, such as proteins, phenolics, lipids and vitamins, this study is focused on the potential activity of rapeseed press cake hydrolysates to be used as raw materials for skincare applications. METHODS: In this study, the protein-rich press residue from the rapeseed oil industry was converted enzymatically into short-chain biologically active peptides using four protease products with varying substrate specificity - Alcalase 2.4L FG, Protex 6L, Protamex and Corolase 7089. The antioxidant, anti-wrinkle and anti-inflammatory activities of the obtained hydrolysates were evaluated in vitro while their biocompatibility with human skin fibroblasts was tested. RESULTS: All hydrolysates were biocompatible with skin fibroblasts after 24 h of exposure, while the non-hydrolysed extract induced cell toxicity. Alcalase 2,4L FG and Protex 6L-obtained hydrolysates were the most promising extracts showing improved bioactivities suitable for skin anti-ageing formulations, namely antioxidant activity, inhibiting approximately 80% cellular reactive oxidative species, anti-inflammatory and anti-wrinkle properties, inhibiting around 36% of myeloperoxidase activity and over 83% of elastase activity. CONCLUSION: The enzymatic technology applied to the rapeseed oil industry costream results in the release of bioactive compounds suitable for skincare applications.

Keratins and lipids in ethnic hair.

Human hair has an important and undeniable relevance in society due to its important role in visual appearance and social communication. Hair is mainly composed of structural proteins, mainly keratin and keratin associated proteins and lipids. Herein, we report a comprehensive study of the content and distribution of the lipids among ethnic hair, African, Asian and Caucasian hair. More interestingly, we also report the study of the interaction between those two main components of hair, specifically, the influence of the hair internal lipids in the structure of the hair keratin. This was achieved by the use of a complete set of analytical tools, such as thin layer chromatography-flame ionization detector, X-ray analysis, molecular dynamics simulation and confocal microscopy. The experimental results indicated different amounts of lipids on ethnic hair compositions and higher percentage of hair internal lipids in African hair. In this type of hair, the axial diffraction of keratin was not observed in X-ray analysis, but after hair lipids removal, the keratin returned to its typical packing arrangement. In molecular dynamic simulation, lipids were shown to intercalate dimers of keratin, changing its structure. From those results, we assume that keratin structure may be influenced by higher concentration of lipids in African hair.

Keratin-based peptide: biological evaluation and strengthening properties on relaxed hair.

A peptide based on a fragment of hair keratin type II cuticular protein, keratin peptide (KP), was studied as a possible strengthening agent for weakened relaxed hair. The peptide was prepared both in aqueous water formulation (WF) and organic solvent formulations (OF), to determine the effect of organic solvents on peptide interaction with hair and the differences in hair recovery. Both peptide formulations were shown to improve mechanical and thermal properties of weakened hair with peptide in OF showing the stronger effect. As a potential new hair care product, and so would necessitate contact with skin, the cytotoxicity and genotoxicity of the peptide were also evaluated through different methodologies (Alamar Blue assay, 2'-7'-dichlorofluorescein probe, cell morphology and growth and evaluation of DNA damage by an alkaline version of the comet assay) in skin fibroblasts. These tests are indicators of the potential of peptide to cause irritation on skin or to be carcinogenic, respectively. The peptide in WF did not cause cytotoxicity or genotoxicity in any of the concentrations tested. The presence of OF, however, induced a 20% decrease in cell viability in all of the range of concentrations used after 72-h incubation. Moreover, OF inhibited cell growth and was considered genotoxic at first contact with cells. The peptide was therefore considered a promising strengthening agent for hair and was shown to be innocuous when applied in WF.

Polimiosite tuberculosa. / Tuberculous polymyositis

Os autores descrevem um caso de comprometimento muscular da tuberculose, cujo foco primario nao foi evidenciado. A manifestacao inicial foi tromboflebites de repeticao. Seguiram-se artralgias, diminuicao da forca muscular, alem de coxas e bracos; atrofia muscular importante das regioes escapulares e glutea; emagrecimento importante e massas musculares endurecidas. A biopsia muscular mostrou granuloma tuberculoide com necrose de caseificacao. Houve excelente resposta com o esquema triplice antituberculoso