Does the Incorporation of Graphene Oxide into PMMA Influence its Antimicrobial Activity?

INTRODUCTION: The increase in infectious diseases mediated by oral bacteria has been one of the most potent threats to human health, specifically to the elderly. Researchers seek to incorporate antimicrobial nanomaterials into PMMA to control the colonization of microorganisms and reduce deadly diseases. OBJECTIVE: To conduct a systematic review to answer the question: "Does graphene oxide incorporated into polymethylmethacrylate influence its antimicrobial activity?" METHODS: The electronic search was performed in PubMed, Embase, Web of Science, Scopus, and Google Scholar databases, and articles published until October 2021 were selected. The search terms were: ("acrylic resin" OR PMMA) AND (graphene OR "oxide graphene") AND (antimicrobial OR antibacterial OR "anti-infective agent"). The risk of bias analysis of the articles was performed using the quasi-experimental study assessment tool adapted from the JBI. RESULTS: Two hundred and fifty-nine articles were found in the databases. After removing the duplicates, 245 were analyzed by title and abstract. Of these, 06 were selected for full reading, of which 03 met the eligibility criteria and were included in this systematic review. CONCLUSION: This systematic review's findings can infer that the incorporation of graphene in the form of graphene-based coatings to PMMA showed antimicrobial effectiveness.

Denture Adhesives Associated with Silver Vanadate: Antimicrobial Approach Against Multi- Species Biofilms on Acrylic Resin Surfaces.

Alternatives have been sought to add an antimicrobial property to denture adhesives. This study evaluated the antimicrobial potential of adhesives associated with nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3). Specimens in acrylic resin were treated with the adhesives associated with ß-AgVO3 (1%, 2.5%, 5% and 10%). As control, specimens treated only with Ultra Corega Cream (UCC) or Ultra Corega Powder (UCP) adhesive were used. Multispecies biofilm of Candida albicans, Candida glabrata, Streptococcus mutans and Staphylococcus aureus was evaluated by counting colony forming units per milliliter (CFU/mL), colorimetric assay and fluorescence microscopy. The data were analyzed using the two-way analysis of variance (ANOVA) and Bonferroni multiple comparisons test (α=0.05). For both adhesives, a small amount of ß-AgVO3 (1%) completely inhibited S. mutans (P⟨0.05). For the other microorganisms, there was a reduction in metabolic activity and complete inhibition in the groups with intermediate or greater amounts of nanomaterial (P⟨0.05), except for C. albicans, which was reduced (P⟨0.05) but not completely inhibited in UCP. Microscopy that showed less biofilm in the groups with ß-AgVO3 and in the UCC than UCP. Denture adhesives in powder and cream form with ß-AgVO3 showed potential antimicrobial activity against multispecies biofilm. Powder adhesive showed higher biofilm formation.

Zirconia Implants Produced by Additive Manufacturing - A Scoping Review.

INTRODUCTION: Additive manufacturing is a tool with potential use in medicine and dentistry. The manufacture of metals and composites is already advanced, however, concerns about titanium hypersensitivity, tissue staining, and corrosion caused by gradual material degradation encourage research into more biocompatible alternatives. OBJECTIVE: This systematic scoping review aimed to gather studies that evaluated zirconia implants produced by additive manufacturing to describe the current stage of the printing technique and the final product. METHODS: Searches in Embase, PubMed, SCOPUS, Web of Science, and Google Scholar databases were enriched with manual searches between February and March 2021 and updated in June 2022 using keywords: zirconium implants, zirconium oxide, additive manufacturing, rapid prototyping, 3D printing, selective laser melting, and electron beam melting. The criteria included studies that evaluated or described zirconia implants obtained by 3D printing, with a direct relationship to dentistry or orthopedics. RESULTS: The database search resulted in 671 articles. Eight articles were selected for full reading and remained in this systematic review. CONCLUSION: The printing technique for zirconia implants is promising. However, further studies are required before implants produced by the printing technique can be tested clinically. The literature with results regarding the impression product is still limited.

Factors that Affect the Shear Bond Strength of Pit and Fissure Sealants to Tooth Structure: A Systematic Review.

INTRODUCTION: Pit and fissure sealants are effective in preventing caries disease, however, they may present flaws that damage the physical barrier leading to treatment failure. OBJECTIVE: To answer the question ''Do pit and fissure sealants present good adhering to the dental structure when analyzed by their resistance to shear/microshear?". METHODS: This systematic review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) and was recorded in Open Science Framework. Embase, PubMed, SCOPUS, and Web of Science databases were used for the search strategy. The articles were selected according to the eligibility criteria. The risk of bias was performed with the adaptation of the quasi-experimental studies tool by Joanna Briggs Institute (JBI). RESULTS: 1245 studies were found in the databases when applying the search strategy, after removal of duplicates 881 were evaluated and 44 were selected. After applying the JBI tool, 30 studies presented low risk and 15 moderate risk of bias. Meta-analysis was not possible to performed due to the heterogeneity of the studies. CONCLUSION: The adhesion is dependent on the application protocol, and among the protocols evaluated, conditioning with 37% phosphoric acid for 60 seconds and contamination of the substrate, as these can affect sealant adhesion.

Prevention of Caries in Cancer Patients: A Systematic Review on the Effectiveness of Dental Materials.

This study aims to identify dental materials and their effectiveness in preventing caries in patients after chemotherapy and radiotherapy for the head and neck. The electronic search was performed in PubMed, Science Direct, Embase and Scopus. All 653 articles found passed through a double-blinded screening process. The exclusion of articles by reading titles and abstracts selected 16 articles for full reading, of which 4 were included into the study. A risk of bias analysis for non-randomized and randomized articles was performed using respectively the ROBINS I and ROB II tools. The data extraction suggested that the casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), in association with fluorine, is able to form harder surfaces compared to the control group, the intraoral fluoride-releasing system (IFRS) effectiveness is similar to the fluorine in gel and a mouthwash composed of natural enzymes (Oral7) did not demonstrate effectiveness in the prevention dental caries. New randomized controlled clinical trials are necessary to evaluate the effectiveness of prevention when applying dental materials in patients after treatment of head and neck cancer.

Surface Characteristics and Microbial Adhesion in Polymethylmethacrylate for Denture Base Submitted to Antimicrobial Agents and Cleaning Agents: A Systematic Review.

This review aimed to identify the influence of antimicrobial and cleaning agents on surface characteristics such as surface free energy (SFE) and wettability, and microbial adhesion in polymethylmethacrylate (PMMA) for denture base. The review question, based on PICO, was: "Does intervention with antimicrobial and cleaning agents in PMMA influence the surface free energy, wettability, and consequently the microbial adhesion?" and the protocol was registered in Open Science Framework (osf. io/v3xgn). The search was performed in PubMed, Lilacs, Embase, Scopus, and Science Direct databases, using the terms: ("acrylic resin" OR PMMA) AND (antimicrobial OR antibacterial) AND ("electrostatic interaction" OR surface free energy) AND (biofilm OR "bacteria adhesion"), and resulted in 462 articles, of which 7 were included. The antimicrobials polypara-xylylene, carboxybetaine methacrylate, ethylene glycol methacrylate phosphate, and deposition of F and Ag ions in PMMA influenced the SFE and wettability. Denture cleaners reduced microbial adhesion. Five of the included studies evaluated the microbial adhesion, however, only two observed a direct relationship between SFE, wettability, and microbial adhesion. It was concluded that the intervention with antimicrobial and cleaning agents in PMMA can interfere in SFE and surface wettability, but no correlation was observed between microbial adhesion and these surface characteristics in PMMA.

Mini-Implants for Mandibular Overdentures: Cost-Effectiveness Analysis alongside a Randomized Trial.

Mandibular overdentures retained by 2 conventional implants have been considered the standard of care for complete edentulism, according to the McGill and York consensuses. However, many patients refuse this treatment modality due to the associated costs and postsurgical discomfort. Mini-implants have the chance to overcome these limitations due to their potentially lower costs and a relatively uncomplicated surgical technique. This study compared treatment costs and incremental cost-effectiveness following the insertion of mini-implants (2 or 4) or 2 standard-size implants for the retention of mandibular overdentures, by means of a randomized clinical trial. In total, 120 edentulous participants (mean age 59.5 ± 8.5 y) were randomly allocated into 3 groups according to treatment received: 4 mini-implants (group 1), 2 mini-implants (group 2), or 2 standard implants (group 3). Treatment costs and outcomes (Oral Health Impact Profile for Edentulous [OHIP-EDENT] and satisfaction with the dentures) were evaluated after 6 mo. Incremental cost-effectiveness ratios (ICERs) were calculated for each intervention in terms of cost per 1-point change in patient outcomes. A 1-way sensitivity analysis was performed considering a 95% confidence interval variation in cost and outcome parameters, represented in tornado diagrams. Overall treatment cost was the lowest for group 2 (average cost: US$318.08), followed by group 1 (US$510.75) and group 3 (US$566.13). Groups did not differ in terms of the length of unscheduled appointments and time spent by participants. In summary, our findings indicate that mandibular overdentures retained by 2 or 4 mini-implants are less costly compared to 2-implant overdentures. Despite the lower costs of overdentures retained by 2 mini-implants, those retained by 4 mini-implants showed further improvement in patient-reported outcomes and reduced costs compared to standard implants ( ClinicalTrials.gov NCT01411683). Knowledge Transfer Statement: This report shows that mini-implant retained overdentures are less costly than overdenture treatment on 2 standard-sized implants. Treatment with 2 mini-implants is an effective procedure to substantially save resources, whereas treatment with 4 mini-implants provides better results from a patient perspective combined with slightly reduced costs compared to the treatment with 2 standard implants. Therefore, mini-implant overdentures may be effective and more accessible than overdentures on 2 standard-size implants for those with limited incomes.

Effect of exercise on cardiovascular parameters in search and rescue-trained dogs / Efeito do exercício sobre parâmetros cardiovasculares em cães em treinamento de busca, resgate e salvamento

Physical activity alters the cardiovascular system of dogs, depending on the exercise characteristics and the animal's physical conditioning. Little is known about the cardiovascular changes in rescue-trained dogs. This study evaluated the cardiovascular responses to a search and rescue exercise session to differentiate these alterations from cases of exhaustion or some possible pathology. Nine healthy rescue-trained dogs that trained for at least one year were used. Seven German Shepherds and two Belgian Shepherd Malinois were evaluated twice, immediately before exercise (M0) and immediately after a 20-minute training (M1). Electrocardiographic, echocardiographic, and systemic blood pressure (SBP) measurements were performed at each evaluation. Heart rate was evaluated in three moments, M0, M1 and five minutes after the end of the physical activity (M2). The results indicated that training increased oxygen demand and significantly increased cardiac output, left ventricular volume in diastole and aortic artery diameter, and the contraction force with the increased mitral annular motion without impairing systolic and diastolic cardiac functions. Heart rate values immediately and five minutes after exercise were similar to baseline values. Training did not alter SBP and the electrocardiographic parameters. The present study indicated good cardiac performance to the physical effort of rescue-trained dogs and reduced the chances of poor performance and the occurrence of sudden death caused by exercise in response to the pattern of activity performed.(AU)

A atividade física acarreta diversas mudanças no sistema cardiovascular dos cães, dependendo das características do exercício realizado e do condicionamento físico do animal. Pouco se sabe sobre as alterações cardiovasculares causadas pelo treinamento de busca, resgate e salvamento. Objetivou-se, com este estudo, avaliar as respostas cardiovasculares após uma sessão desse tipo de treino, a fim de diferenciar essas alterações de casos de exaustão ou de alguma possível patologia. Foram utilizados nove cães saudáveis em treinamento de busca, resgate e salvamento há pelo menos um ano, sendo sete da raça Pastor Alemão e dois da raça Pastor Belga Malinois. Os cães foram submetidos a dois momentos de avaliação: M0 imediatamente antes do exercício e M1 imediatamente após um treinamento de 20 minutos. Em cada avaliação, foram realizados os exames eletrocardiográfico e ecocardiográfico e a aferição da pressão arterial sistólica sistêmica. Apenas a frequência cardíaca foi avaliada em três momentos, em M0, M1 e após cinco minutos do término da atividade física (M2). Os resultados obtidos indicam que o treinamento causa um aumento na demanda de oxigênio, provocando um aumento significativo no débito cardíaco, no volume ventricular esquerdo em diástole e no diâmetro da artéria aorta, assim como um aumento em um dos parâmetros de contratilidade cardíaca (movimento anular de mitral), sem causar prejuízo às funções cardíacas sistólicas e diastólicas. Os valores da FC imediatamente após e cinco minutos após o exercício foram similares aos valores basais. A PASS e os parâmetros eletrocardiográficos não se alteraram após o treinamento. Os achados encontrados indicam um bom desempenho cardíaco ao esforço físico dos cães de busca, resgate e salvamento, reduzindo-se as chances de má performance e de ocorrência de morte súbita causada pelo exercício, em resposta ao padrão da atividade realizada.(AU)

Echocardiographic parameters in dogs treated with acepromazine and fentanyl / Parâmetros ecocardiográficos em cães tratados com acepromazina e fentanil

Considering that the use of tranquillizers could optimize the performance of the echocardiogram, this study aimed to evaluate the effect of protocols with acepromazine and fentanyl on the echocardiographic parameters of healthy dogs, besides their effect in systolic blood pressure (SBP), respiratory rate (RR), heart rate (HR), time spent for examination and sedation scale. Ten adult dogs were submitted to different tranquilizing protocols 20 minutes before the echocardiographic examination, totalling five treatments for each pair, performed at seven-day intervals between evaluations. The treatments were CT (control treatment), IAT (intramuscular acepromazine), OAT (oral acepromazine), FT (fentanyl) and AFT (acepromazine associated with fentanyl). In addition to the echocardiographic evaluation, SBP, degree of reassurance, duration of the exam, HR and RR in the different protocols were evaluated. There was a significant decrease of SBP in OAT. There was a significant reduction in left ventricular diameter during systole and diastole and mitral annular movement in IAT, OAT and AFT, compared with CT. There was a decrease in tricuspid annular plane systolic excursion and increase in mitral E/mitral A ratio in IAT and OAT when compared with CT. All the tranquillizer protocols studied were found to significantly reduce HR, that facilitated the echocardiographic examination.(AU)

Considerando que o uso de tranquilizantes poderia otimizar a realização do ecocardiograma, objetivou-se com este estudo avaliar o efeito da tranquilização com acepromazina e fentanil sobre os parâmetros ecocardiográficos em cães saudáveis, bem como o efeito na pressão arterial sistólica (PAS), na frequência respiratória (FR), na frequência cardíaca (FC), no tempo gasto para a realização do exame e na escala de sedação. Dez cães adultos foram submetidos a diferentes protocolos tranquilizantes, 20 minutos antes da avaliação ecocardiográfica, totalizando cinco tratamentos para cada dupla, realizados com intervalos de sete dias entre as avaliações. Os tratamentos foram: TC (tratamento controle), TAI (acepromazina intramuscular), TAO (acepromazina oral), TF (fentanil) e TAF (acepromazina associada ao fentanil). Além dos parâmetros ecocardiográficos, foram avaliados a PAS, o grau de tranquilização, o tempo de duração do exame e a FC e a FR nos diferentes protocolos. Houve diminuição significativa da PAS no TAO. Observou-se redução significativa do diâmetro do ventrículo esquerdo em sístole e diástole e do movimento anular de mitral nos protocolos TAI, TAO e TAF, comparados com o TC. Observou-se também uma redução da excursão sistólica do plano anular tricúspide e aumento da relação mitral E/mitral A nos protocolos TAI e TAO quando comparados ao TC. Todos os protocolos de tranquilização reduziram significativamente a FC, o que facilitou a realização do exame.(AU)

Parâmetros ecocardiográficos em cães saudáveis tratados com acepromazina, meperidina e sua associação / Echocardiographic parameters in healthy dogs treated with acepromazine, meperidine and their association

Objetivou-se avaliar os efeitos da tranquilização com meperidina, acepromazina e de sua associação sobre os parâmetros ecocardiográficos em cães. Foram utilizados 12 cães adultos, da raça Rottweiler, submetidos ao exame ecocardiográfico sem utilização de sedação (controle - TC) e a três protocolos de tratamento, utilizando-se meperidina (TM), acepromazina (TA) e a associação dos medicamentos (TMA). As variáveis foram analisadas pelo teste de Tukey (P<0,05). Observou-se que as médias obtidas na onda A do fluxo mitral em TA e TMA diminuíram significativamente com relação ao TM, que não diferiu do TC. Houve uma diminuição significativa no valor de movimento anular mitral (MAM) e excursão sistólica do plano anular tricúspide (ESPAT) no TA. Não houve diferença significativa para os valores de fração de encurtamento (FE) entre TA e os demais tratamentos. Entretanto, observou-se que 57,3% dos cães apresentaram valores de FE abaixo da normalidade. As alterações encontradas podem ser decorrentes dos efeitos hipotensores da acepromazina utilizada de forma isolada. Conclui-se que a meperidina ou sua associação com acepromazina não alteram os parâmetros ecocardiográficos em cães saudáveis e que a acepromazina, utilizada isoladamente, causa alteração nos parâmetros de função sistólica dos cães, não sendo recomendada para a contenção química dos cães submetidos ao ecocardiograma, o que poderia levar à má interpretação do exame.(AU)

The aim of this study was to evaluate the effects of sedation with meperidine, acepromazine and its association on the echocardiographic parameters in dogs. Twelve adult Rottweilers were used and subjected to the echocardiography examination without the use of sedation (control - CT) and subjected to three treatment protocols using meperidine (MT), acepromazine (AT), and the combination of drugs (MAT). Variables were analyzed by Tukey test (p<0,05). The averages obtained in A-wave of mitral inflow in AT and MAT decreased significantly compared to MT, which did not differ from CT. There was a significant decrease in the measurement of mitral annulus motion (MAM) and tricuspid annular plane systolic excursion (TAPSE) at TA. There was no significant difference in shortening fraction (SF) values between TA and other treatments. However, it was observed that 57.3% of the dogs showed SF values below the normal range for the species. All changes found may be due to the hypotensive effects of acepromazine used in isolation. In conclusion, meperidine or its association with acepromazine does not alter echocardiographic parameters in healthy dogs and acepromazine, used alone, causes changes in the parameters of systolic function and is not recommended for sedation of dogs submitted to echocardiogram, since it could cause a misinterpretation of the exam.(AU)

Impact of biogenic substrates on sulfamethoxazole biodegradation kinetics by Achromobacter denitrificans strain PR1.

Pure cultures have been found to degrade pharmaceutical compounds. However, these cultures are rarely characterized kinetically at environmentally relevant concentrations. This study investigated the kinetics of sulfamethoxazole (SMX) degradation by Achromobacter denitrificans strain PR1 at a wide range of concentrations, from ng/L to mg/L, to assess the feasibility of using it for bioaugmentation purposes. Complete removal of SMX occurred for all concentrations tested, i.e., 150 mg/L, 500 µg/L, 20 µg/L, and 600 ng/L. The reaction rate coefficients (kbio) for the strain at the ng/L SMX range were: 63.4 ± 8.6, 570.1 ± 15.1 and 414.9 ± 124.2 L/g[Formula: see text]·day), for tests fed without a supplemental carbon source, with acetate, and with succinate, respectively. These results were significantly higher than the value reported for non-augmented activated sludge (0.41 L/(g [Formula: see text]·day) with hundreds of ng/L of SMX. The simultaneous consumption of an additional carbon source and SMX suggested that the energetic efficiency of the cells, boosted by the presence of biogenic substrates, was important in increasing the SMX degradation rate. The accumulation of 3-amino-5-methylisoxazole was observed as the only metabolite, which was found to be non-toxic. SMX inhibited the Vibrio fischeri luminescence after 5 min of contact, with EC50 values of about 53 mg/L. However, this study suggested that the strain PR1 still can degrade SMX up to 150 mg/L. The results of this work demonstrated that SMX degradation kinetics by A. denitrificans PR1 compares favorably with activated sludge and the strain is a potentially interesting organism for bioaugmentation for SMX removal from polluted waters.

Mini vs. Standard Implants for Mandibular Overdentures: A Randomized Trial.

A mandibular implant-retained overdenture is considered a first-choice treatment for edentulism. However, some aspects limit the use of standard implants-for example, the width of edentulous ridges, chronic diseases, fear, or costs. This randomized trial compared mandibular overdentures retained by 2 or 4 mini-implants with standard implants, considering oral health-related quality of life (OHRQoL), patient satisfaction, and complications such as lost implant. In sum, 120 edentulous men and women (mean age, 59.5 ± 8.5 y) randomly received 4 mini-implants, 2 mini-implants, or 2 standard implants. Participants provided data regarding OHRQoL and satisfaction until 12 mo. Clinical parameters, including implant survival rate, were also recorded. Both 2 and 4 mini-implants led to better OHRQoL, compared with 2 standard implants. Treatment with 4 mini-implants was more satisfying than 2 standard implants, with 2 mini-implants presenting intermediate results. Implant survival rate was 89%, 82%, and 99% for 4 mini-implants, 2 mini-implants, or 2 standard implants, respectively. Overdentures retained by 4 or 2 mini-implants can achieve OHRQoL and satisfaction at least comparable with that of 2 standard implants. However, the survival rate of mini implants is not as high as that of standard implants (ClinicalTrials.gov NCT01411683).

[Kikuchi-Fujimoto's disease and adult-onset Still's disease. A rare co-occurence]. / Kikuchi-Fujimoto-Syndrom und adulter Morbus Still. Eine seltene Koinzidenz.

Kikuchi-Fujimoto's disease and adult-onset Still's disease are rare inflammatory conditions with overlapping clinical features. Adult-onset Still's disease causes high fevers, a typical salmon-colored rash, and joint pain. The principal symptom of Kikuchi's disease is cervical lymphadenopathy with typical histopathological features including extensive necrosis of the involved lymph nodes. Here, we report on a rare case of concurrent adult-onset Still's disease and Kikuchi-Fujimoto syndrome in a young Caucasian patient.

Short-term post-operative pain and discomfort following insertion of mini-implants for retaining mandibular overdentures: a randomized controlled trial.

The retention of removable dentures by mini-implants is a relatively recent treatment modality and may lead to minimal post-operative trauma. This study compared post-operative pain and discomfort following the insertion of mini-implants (two or four) or two standard-size implants for the retention of mandibular overdentures. One hundred and twenty edentulous participants (mean age 59.5 ± 8.5 years) were randomly allocated into three groups according to received treatment: (GI) four mini-implants, (GII) two mini-implants or (GIII) two standard implants. Seven days after implant insertion, patients answered questions (100-mm VAS) relating to pain, swelling, and discomfort with chewing, speech and hygiene, considering their experiences during the 1st and 6th day. Groups were compared by two-way anova (α = 0.05). All participants (GI: 38; GII: 42; GIII: 40) were analysed after 7 days. At the 6th day, GI felt significantly higher pain than GII and GIII. GI also reported more difficulty in performing oral hygiene practices than GIII during the 1st day. There was no significant difference between groups for the other questions and periods. No participant suffered unexpected side effects. The use of four mini-implants induces more intense post-operative pain at the 6th day than the insertion of two mini- or conventional fixtures, as well as more difficult oral hygiene on the 1st day. Clinicaltrials.gov, NCT01411683; FAPESP, 2011/00688-7 and 2011/23347-0.

Induction of eosinophil apoptosis by hydrogen peroxide promotes the resolution of allergic inflammation.

Eosinophils are effector cells that have an important role in the pathogenesis of allergic disease. Defective removal of these cells likely leads to chronic inflammatory diseases such as asthma. Thus, there is great interest in understanding the mechanisms responsible for the elimination of eosinophils from inflammatory sites. Previous studies have demonstrated a role for certain mediators and molecular pathways responsible for the survival and death of leukocytes at sites of inflammation. Reactive oxygen species have been described as proinflammatory mediators but their role in the resolution phase of inflammation is poorly understood. The aim of this study was to investigate the effect of reactive oxygen species in the resolution of allergic inflammatory responses. An eosinophilic cell line (Eol-1) was treated with hydrogen peroxide and apoptosis was measured. Allergic inflammation was induced in ovalbumin sensitized and challenged mouse models and reactive oxygen species were administered at the peak of inflammatory cell infiltrate. Inflammatory cell numbers, cytokine and chemokine levels, mucus production, inflammatory cell apoptosis and peribronchiolar matrix deposition was quantified in the lungs. Resistance and elastance were measured at baseline and after aerosolized methacholine. Hydrogen peroxide accelerates resolution of airway inflammation by induction of caspase-dependent apoptosis of eosinophils and decrease remodeling, mucus deposition, inflammatory cytokine production and airway hyperreactivity. Moreover, the inhibition of reactive oxygen species production by apocynin or in gp91(phox-/-) mice prolonged the inflammatory response. Hydrogen peroxide induces Eol-1 apoptosis in vitro and enhances the resolution of inflammation and improves lung function in vivo by inducing caspase-dependent apoptosis of eosinophils.

O uso do peritônio de paca conservado em solução supersaturada de açúcar a 300 por cento ou glicerina a 98 por cento implantados na parede abdominal de ratos / The use of paca peritoneum preserved in supersaturated sugar solution 300 percent or glycerine 98 percent implanted in the abdominal wall of rats

Na busca de material biológico alternativo para a realização de implantes, objetivou-se com o presente estudo avaliar comparativamente a implantação do peritônio de paca, uma nova opção de biomaterial, conservado em solução supersaturada de açúcar a 300 por cento e conservado em glicerina a 98 por cento na parede abdominal de ratos Wistar. Foram utilizados 60 ratos, machos, da linhagem Wistar, pesando entre 150 e 200 gramas, organizados nos seguintes grupos experimentais: grupo controle (GI), grupo peritônio conservado em solução supersaturada de açúcar a 300 por cento (GII) e grupo peritônio conservado em glicerina a 98 por cento (GIII), cada um com 20 animais. Os grupos GII e GIII receberam o enxerto de peritônio da paca conservado em solução de açúcar 300 por cento e glicerina 98 por cento, respectivamente, e o grupo GI não recebeu a membrana. Cinco ratos de cada grupo foram submetidos à eutanásia em quatro momentos distintos: sete, 15, 30 e 60 dias de pós-operatório para avaliações macroscópicas e microscópicas da interface implante-tecido nativo. Apesar de reações adversas observadas em 57,5 por cento dos animais do grupo GII e GIII, em 95 por cento dos animais desses grupos houve boa cicatrização da membrana. Na análise histológica, verificou-se a presença de grande infiltrado inflamatório nos períodos iniciais (sete e 15 dias) e grande presença de tecido conjuntivo nos momentos finais (30 e 60 dias). Concluiu-se que o peritônio da paca como membrana biológica conservado nos meios estudados pode ser utilizado com segurança na parede abdominal de ratos; ainda, que sua conservação em solução supersaturada de açúcar a 300 por cento permitiu melhor maleabilidade no ato cirúrgico...

In the search for alternative biological material to perform implants, this study aimed to compare the implantation of paca peritoneum, a new biomaterial option, preserved in supersaturated sugar solution 300 percent and preserved in glycerin 98 percent in the abdominal wall of Wistar rats. A total of 60 male rats from the Wistar strain weighing between 150 and 200 grams were housed into three different experimental groups: control group (GI), peritoneum preserved in supersaturated sugar solution 300 percent group (GII) and peritoneum preserved in glycerin 98 percent group (GIII), with 20 animals each. The GII and GIII received the paca peritoneum graft preserved in sugar solution 300 percent and glycerin 98 percent, respectively and group GI did not receive any membrane. Five rats from each group were euthanized at four different times: seven, 15, 30 and 60 days post-surgery for macroscopic and microscopic evaluations in graft-native tissue interface. Despite the adverse reactions observed in 57.5 percent of GII and GIII, there was good healing of the membrane in 95 percent of the animals in these groups. Upon histological examination there was a large presence of inflammatory infiltrates in the initial periods (seven and 15 days) and a large presence of connective tissue in the final stages (30 and 60). It was concluded that the paca peritoneum as biological membrane preserved as presented in this study can be used safely in the abdominal wall of rats, the preservation in supersaturated sugar solution 300 percent allowed better flexibility during surgery...

Assessment of surface hardness of acrylic resins submitted to accelerated artificial aging.

AIM: The aim of this study was to assess the influence of accelerated artificial aging (AAA) on the surface hardness of acrylic resins. METHODS: The following three commercial brands of acrylic resins were tested: Vipi Flash (autopolymerized resin), Vipi Wave (microwave heat-polymerized resin) and Vipi Cril (conventional heat-polymerized resin). To perform the tests, 21 test specimens (65x10x3 mm) were made, 7 for each resin. Three surface hardness readings were performed for each test specimen, before and after AAA, and the means were submitted to the following tests: Kolmogorov-Smirnov (P>0.05), Levene Statistic, Two-way ANOVA, Tukey Post Hoc (P<0.05) with the SPSS Statistical Software 17.0. RESULTS: The analysis of the factors showed significant differences in the hardness values (P<0.05). Before aging, the autopolymerized acrylic resin Vipi Flash showed lower hardness values when compared with the heat-polymerized resin Vipi Cril (P=0.001). After aging, the 3 materials showed similar performance when compared among them. The Vipi Cril was the only one affected by AAA and showed lower hardness values after this procedure (Pp=0.003). CONCLUSION: It may be concluded that accelerated artificial aging influenced surface hardness of heat-polymerized acrylic resin Vipi Cril.

Estrutura, ultraestrutura e morfometria da aorta de paca (Cuniculus paca, Linnaeus, 1766) criada em cativeiro / Structure, ultrastructure and morphometry of the aorta in the paca (Cuniculus paca, Linnaeus, 1766) raised in captivity

Descreveram-se a morfologia, morfometria e ultraestrutura de segmentos das porções torácica e abdominal da aorta de quatro pacas (Cuniculus paca) adultas. Os segmentos aórticos foram analisados à microscopia de luz e à microscopia eletrônica de varredura. Mensuraram-se as espessuras do complexo formado pelas túnicas íntima e média, além da túnica adventícia. Os valores referentes à espessura do complexo formado pelas túnicas íntima e média da aorta torácica cranial foram significativamente maiores (média: 702,19µm) que os valores de outros segmentos aórticos analisados (médias: 354,18µm; 243,55µm). As camadas das paredes do vaso apresentaram variações entre si quanto à estrutura e espessura, supostamente em razão de adaptação à exigência funcional.

The aim of this study was to describe the morphology, morphometry and ultrastructure of segments of thoracic and abdominal aorta portions in four male and female paca (Cuniculus paca). Parts of the segments were examined by light microscopy and part by scanning electron microscopy. Thickness measurements of the tunica intima and media complex and tunica adventitia of the aorta were taken. In all animals the thickness values for the tunica intima and media complex of the cranial thoracic aorta were significantly higher (mean: 702.19µm) when compared to the values of other aortic segments analyzed (means: 354.18µm; 243.55µm). The layers of the vessel walls show variations in structure and thickness, presumably due to an adaptation to functionaldemand.

Malignant pilomatricoma in a dog.

An 11-year-old female German shepherd dog was presented with a history of lameness and pain in the left forelimb. Clinical examination revealed ataxia of the hindlimbs and a subcutaneous mass in the left prescapular region. Radiography revealed metastatic foci in the left humerus, lung and abdomen. Gross necropsy examination revealed a firm, white mass in the left prescapular region. Multiple nodules with similar characteristics were observed in the lung, liver and spleen. Bone lysis was noted in the humerus and the fifth to seventh lumbar vertebrae. Microscopical examination revealed a proliferation of basal cells forming irregular islands of various sizes and surrounding extensive zones of keratinized 'ghost' cells. A definitive diagnosis of malignant pilomatricoma was made. This is a rare tumour in dogs with no previous report of metastasis to the spleen and liver.

Cutaneous myxosarcoma with pulmonary metastases in a dog.

The pathological findings in a 13-year-old dog with cutaneous myxosarcoma with pulmonary metastases are described. Grossly, there was a large subcutaneous mass in the right scapular region, a smaller nodule in the caudal abdominal region and a fibrotic mass at a fracture site in the right hindlimb. Radiographic examination revealed several pulmonary nodules. Microscopical evaluation revealed a myxosarcoma characterized by the proliferation of spindle to stellate cells with multiple prominent nucleoli and vascular invasion. The neoplastic cells were haphazardly arranged in a mucopolysaccharide matrix. Immunohistochemically, the neoplastic cells expressed vimentin, but not cytokeratin or glial fibrillary acidic protein. There was restricted expression of desmin, smooth muscle actin and S-100 protein.