Deforestation impacts on dengue incidence in the Brazilian Amazon.

The objective of the study is to perform the spatial analysis of the conditioning factors for the increase in the incidence rate of dengue cases in municipalities located in the Amazon biome, in the period from 2016 to 2021. Three statistical approaches were applied: Moran's index, ordinary least squares regression, and geographically weighted regression. The results revealed that the incidence rates of dengue cases cluster in two areas, both located in the south of the Amazon biome, which is associated with the Arc of Deforestation. The variable deforestation influences the increase in dengue incidence rates revealed by the OLS and GWR model. The adjusted R2 of the GWR model was 0.70, that is, the model explains about 70% of the total case variation of dengue incidence rates in the Amazon biome. The results of the study evidence the need for public policies aimed at the prevention and combat of deforestation in the Amazon region.

Prevalence and anatomopathological characterization of cutaneous squamous cell carcinomas with regional and distant metastases in dogs and cats: 20 cases (1985-2020).

The aim of this study was to assess the prevalence of regional and distant metastases from cutaneous squamous cell carcinomas (SCCs) in dogs (n = 11) and cats (n = 9) in a retrospective case series over 36 years (1985-2020), as well as to characterize its macroscopic aspects (location and size), degree of differentiation (well, moderately and poorly differentiated [WD, MD and PD, respectively]) and the rate of cell proliferation, by counting the AgNORs. Immunohistochemistry (IHC) was used to identify patterns of tumour migration and invasion (islands, ribbons, cords, small aggregates, individual cells [fusiform and amoeboid]) and to evaluate the intensity of desmoplasia and the amount of myofibroblasts. The prevalence of metastatic SCCs was 4.39% (21/478), being 3.8% in dog (12/309) and 5.3% in cat (9/169). Metastases affected lymph nodes in all dogs and 66% (6/9) of cats, and less frequently distant organs. Primary tumours predominantly affected the abdominal skin in dogs and the nasal planum in cats. Among the 20 cases, 52% were MDs, 34% were WDs, and 14% were PDs. Histological lesions suggestive of exposure to chronic solar radiation were present in 57% (8/14). The main patterns of tumour migration and invasion were islands for WD SCCs and individual cells for PD SCCs. MD SCCs had a mix of patterns. In cats, individual spindle cells were restricted to PDs. A marked desmoplastic reaction was more associated with PD SCCs and often with MDs. This study highlights that the prevalence of SCC metastases in dogs and cats is predominantly regional. The IHC was essential in the identification of individual fusiform keratinocytes, whose presence in surgical margins may represent a greater risk of recurrence. Although the presence of myofibroblasts was observed in all infiltrative and metastatic tumours, further studies evaluating these cells may be important to better understand their role in the tumour microenvironment of cutaneous SCCs with metastasis in dogs and cats.

Spatial analysis of socio-economic factors and their relationship with the cases of COVID-19 in Pernambuco, Brazil.

OBJECTIVES: To analyse the spatial distribution of rates of COVID-19 cases and its association with socio-economic conditions in the state of Pernambuco, Brazil. METHODS: Autocorrelation (Moran index) and spatial association (Geographically weighted regression) models were used to explain the interrelationships between municipalities and the possible effects of socio-economic factors on rates. RESULTS: Two isolated clusters were revealed in the inner part of the state in sparsely inhabited municipalities. The spatial model (Geographically Weighted Regression) was able to explain 50% of the variations in COVID-19 cases. The variables proportion of people with low income, percentage of rented homes, percentage of families in social programs, Gini index and running water had the greatest explanatory power for the increase in infection by COVID-19. CONCLUSIONS: Our results provide important information on socio-economic factors related to the spread of COVID-19 and can serve as a basis for decision-making in similar circumstances.

Three dimensional analysis and comparison of human anterior teeth and experimentally created bitemark depressions

A system was proposed to scan dental models to record three-dimensional features seen in the anterior teeth to create a database of dental profiles. Dental casts were randomly selected to create indentations in cowhide leather. Reid Bite Reader was used to measure the bite forces generated by Reynolds Controlled Bite Force Generator to make the teeth impressions. Using the Immersion MicroScribe® 3D, information from the 53 bitemark depressions and 62 sets of dental casts were transferred to an Excel Spreadsheet. Software was developed to perform the 3D comparison using metric and pattern analysis. Statistical analysis showed 100% success when comparing both arches together of the dental casts with the bitemarks or different dental casts.

Population-Based Multicentric Survey of Hepatitis B Infection and Risk Factors in the North, South, and Southeast Regions of Brazil, 10-20 Years After the Beginning of Vaccination.

A population-based hepatitis survey was carried out to estimate the prevalence of hepatitis B virus (HBV) infection and its predictive factors for the state capitals from the north, south, and southeast regions of Brazil. A multistage cluster sampling was used to select, successively, census tracts, blocks, households, and residents in the age group 10-69 years in each state capital. The prevalence of hepatitis B surface antigen (HBsAg) was lower than 1% in the north, southeast, and south regions. Socioeconomic condition was associated with HBV infection in north and south regions. Variables related to the blood route transmission were associated with HBV infection only in the south whereas those related to sexual behavior were associated with HBV infection in the north and south regions. Drug use was associated in all regions, but the type of drug differed. The findings presented herein highlight the diversity of the potential transmission routes for hepatitis B transmission in Brazil. In one hand, it reinforces the importance of national control strategies of large impact already in course (immunization of infants, adolescents, and adults up to 49 years of age and blood supply screening). On the other hand, it shows that there is still room for further control measures targeted to different groups within each region.

Perception of laypersons and dental professionals and students as regards the aesthetic impact of gingival plastic surgery.

OBJECTIVE: To evaluate the degree of perception of laypersons, professionals, and dental students, regarding the aesthetic appearance of the smile in cases of gingival plastic surgery of the maxilla for correction of a gingival smile, by examining alterations in photographs. MATERIALS/METHODS: Alterations were made to an extraoral front-view-photograph of a gingival smile in normal occlusion, by gingival recontouring of the maxilla, simulating a gingival plastic surgery procedure to diminish gingival exposure. For this purpose, specific image-manipulation program (Adobe-Photoshop-Software-CS3) was used. Images were printed on photographic-paper, attached to questionnaire, distributed among laypersons, professionals, and dental students to evaluate degree of aesthetics (n = 150). To evaluate degree of aesthetics, an attractiveness scale was used, with 0 representing hardly attractive, 5 for attractive, and 10 for very attractive. Differences between examiners were examined by Mann-Whitney test. All the statistics were performed with a confidence level of 95 per cent. RESULTS: Both dental professionals and students and laypersons were capable of identifying alterations resulting from gingival plastic surgery. In all evaluated groups, they demonstrated that large gingival extension does not always affect aesthetic appearance of the smile, and maxillary incisors not being much visualized is characterized as hardly attractive, with statistically lower scores being attributed (P < 0.05). CONCLUSIONS: According to aesthetic parameters, the presence of the gingiva is important in the composition of the smile, however, only when exposed to small extent.

Effect of Endodontic Irrigating Solutions on the Micro Push-out Bond Strength of a Fibre Glass Dowel.

PURPOSE: To evaluate the effect of different endodontic irrigating solutions on the micro push-out bond strength of a fiber glass dowel. MATERIAL AND METHODS: Seventy 16-mm long root segments of bovine incisors were prepared and randomly assigned to 7 groups (n=10) according to the type of irrigating solution used prior to the cementation of the intra-radicular fiber glass dowels: G1: 5.25% NaOCl + 17% EDTA; G2: 5.25% NaOCl; G3: 17% EDTA; G4: 2% chlorhexidine gel; G5: 70% alcohol; G6: 11.5% polyacrylic acid; and G7: saline (control). After treatment of intracanal dentin, the glass fibre dowels were cemented with self-adhesive resin cement (RelyX Unicem). Six slices with the thickness of 1.00 ± 0.05 mm were obtained from each tooth at the coronal, middle and apical root thirds (2 slices per third) using a low-speed saw. Micro push-out tests were performed at a crosshead speed of 0.5mm/min and the data (MPa) were analyzed statistically by ANOVA and Tukey's and Dunnett's tests. RESULTS: There were statistically significant differences (p<0.0001) among the irrigating solutions, but no significant difference (p=0.0591) was found among the root thirds. G5 presented the highest bond strength mean of all groups (p<0.0001). The use of 70% alcohol increased the adhesion values by 53% compared to the group control. CONCLUSION: The use of 70% alcohol increased the bond strength of the fiber glass dowel to the dentin walls. However, the push-out bond strength between the dowel and the root dentin was not affected by the root third (coronal, middle and apical).

Photos vs silhouettes for evaluation of profile esthetics between white and black evaluators.

OBJECTIVE: To determine whether photos or silhouettes are adequate methods for evaluating the esthetic profiles of black subjects and whether black and white evaluators have different preferences for esthetic profiles. MATERIALS AND METHODS: One photographic record of the profile of a black female patient with accentuated dental bimaxillary dentoalveolar protrusion was randomly selected. The image of the patient's profile was altered to produce a series of seven photos and seven silhouettes (a total of 14 images) with different lip positions but uniform distances in relation to the esthetic plane created by Ricketts (line E). Fifty black and 50 white lay evaluators were invited to enumerate the photos and silhouettes, produced according to the lip position, in the order in which they considered most esthetically pleasing. RESULTS: The number of preferences found to be within the esthetic norm was slightly higher among the photographs than among the silhouettes; the esthetic profile with a deviation of -2 mm from line E was elected as the most attractive, and the esthetic pattern with a deviation of +6 mm from the normal line E was considered the least attractive. There were no statistically significant differences between the preferences related to the variables race, sex, and educational background. CONCLUSIONS: The esthetic attractiveness of the facial profiles of black subjects in photos and silhouettes was evaluated in a similar manner among black and white evaluators. Among both black and white evaluators, the greatest preference was for the slightly concave profile, which was within the limit considered standard.

Perfil clínico-epidemiológico de vítimas de traumatismo torácico submetidas a tratamento cirúrgico em um hospital de referência / Clinical and epidemiological profile of victims of chest trauma undergoingsurgical treatment at a referral hospital

Objetivos: Descrever o perfil clínico-epidemiológico de vítimas de traumatismo torácico submetidas a tratamento cirúrgico em um hospital de referência em trauma.Métodos: Um estudo epidemiológico transversal analisou os prontuários de todos os pacientes admitidos por traumatismo torácico e submetidos a tratamento cirúrgico entre agosto e novembro de 2011 no Hospital de Urgências de Goiânia.Resultados: Fizeram parte do estudo 89 (89%) homens e 11 (11%) mulheres, a maioria entre 20 e 39 anos (49%). Os ferimentos por arma branca (57,9%) e o hemopneumotórax (45,6%) foram mais frequentes no trauma torácico aberto e os acidentes motociclísticos (62,8%) e o hemotórax (48,8%) mais frequentes no fechado. O raio-x (69%) e a drenagem torácica unilateral (78%) foram os principais meios de diagnóstico e tratamento. Entre os pacientes com trauma torácico aberto, 11 (19,3%) necessitaram de toracotomia; destes, 36,3% apresentavam lesões pulmonares. Grande parte dos pacientes (48%) ficaram internados entre três e quatro dias. A taxa de mortalidade foi de 11%.Conclusões: O perfil das vítimas de trauma torácico que necessitaram de atendimento cirúrgico corresponde principalmente a homens jovens, com lesão decorrente de ferimento por arma branca ou de acidente motociclístico, apresentando hemopneumotórax ou hemotórax. Na maioria dos casos essas lesões foram diagnosticadas por raios-x e tratadas com drenagem torácica fechada. A maior parte dos pacientes teve boa evolução, com tempo de internação curto seguido da alta hospitalar. Estas informações podem auxiliar na organização do atendimento hospitalar de urgência e na implementação de medidas preventivas e de conscientização.

Aims: To describe the clinical and epidemiological profile of victims of chest trauma undergoing surgical treatment at a referral hospital for trauma.Methods: A cross-sectional epidemiological study analysed medical records of all patients admitted with chest trauma and underwent surgery between August and November 2011 in Emergency Hospital of Goiânia.Results: Participants were 89 (89%) men and 11 (11%) women, most between 20 and 39 years (49%). The stab wounds (57.9%) and hemopneumothorax (45.6%) were more frequent in open chest injury and motorcycle accidents (62.8%), and hemothorax (48.8%) was more frequent in blunt trauma. The x-ray (69%) and unilateral chest tube drainage (78%) were the main means of diagnosis and treatment. Among patients with open chest trauma, 11 (19.3%) required thoracotomy and of these, 36.3% had lung lesions. Most patients (48%) were hospitalized for three to four days. The mortality rate was 11%.Conclusions: The profile of victims of chest trauma requiring surgical care consisted mainly of young men with injuries caused by stab wound or motorcycle accidents, presenting hemopneumothorax or hemothorax. In most cases these lesions were diagnosed by x-rays and treated with closed drainage. Most patients had a good outcome, with shorter hospitalization?s time followed by hospital discharge. This information can assist in the organization of emergency hospital care as well as in the implementation of preventive measures and awareness.

Dynamic behaviour of carbocations on zeolites: mobility and rearrangement of the C4H7(+) system.

The mobility and rearrangement of the C4H7(+) system over Chabazite were studied using ab initio molecular dynamics. The results indicated the high mobility of the cations, which can rearrange within picosecond time intervals. Experimental studies of nucleophilic substitution supported the theoretical findings.

Prevalence and risk factors of Hepatitis C virus infection in Brazil, 2005 through 2009: a cross-sectional study.

BACKGROUND: Hepatitis C chronic liver disease is a major cause of liver transplant in developed countries. This article reports the first nationwide population-based survey conducted to estimate the seroprevalence of HCV antibodies and associated risk factors in the urban population of Brazil. METHODS: The cross sectional study was conducted in all Brazilian macro-regions from 2005 to 2009, as a stratified multistage cluster sample of 19,503 inhabitants aged between 10 and 69 years, representing individuals living in all 26 State capitals and the Federal District. Hepatitis C antibodies were detected by a third-generation enzyme immunoassay. Seropositive individuals were retested by Polymerase Chain Reaction and genotyped. Adjusted prevalence was estimated by macro-regions. Potential risk factors associated with HCV infection were assessed by calculating the crude and adjusted odds ratios, 95% confidence intervals (95% CI) and p values. Population attributable risk was estimated for multiple factors using a case-control approach. RESULTS: The overall weighted prevalence of hepatitis C antibodies was 1.38% (95% CI: 1.12%-1.64%). Prevalence of infection increased in older groups but was similar for both sexes. The multivariate model showed the following to be predictors of HCV infection: age, injected drug use (OR = 6.65), sniffed drug use (OR = 2.59), hospitalization (OR = 1.90), groups socially deprived by the lack of sewage disposal (OR = 2.53), and injection with glass syringe (OR = 1.52, with a borderline p value). The genotypes 1 (subtypes 1a, 1b), 2b and 3a were identified. The estimated population attributable risk for the ensemble of risk factors was 40%. Approximately 1.3 million individuals would be expected to be anti-HCV-positive in the country. CONCLUSIONS: The large estimated absolute numbers of infected individuals reveals the burden of the disease in the near future, giving rise to costs for the health care system and society at large. The known risk factors explain less than 50% of the infected cases, limiting the prevention strategies. Our findings regarding risk behaviors associated with HCV infection showed that there is still room for improving strategies for reducing transmission among drug users and nosocomial infection, as well as a need for specific prevention and control strategies targeting individuals living in poverty.

Validation of the functional and social performance - DSF-84 checklist: preliminary study.

PURPOSE: To develop, implement and validate an instrument for assessing the functional and social performance of young male adults with lower limb amputees based on the international classification of functionality, incapacity, and health. METHODS: Developed the instrument, the items were grouped into domains (organic aspects - OA, daily activities - DA, performance components - PC, social participation - SP and environmental factors - EF) for statistical analysis. The implementation of the instrument was filmed for validation. Four assessors watched the films on two occasions and gave scores. Intra-class correlation was used to evaluate intra- and inter-rater reproducibility and to the internal consistency was calculated by Cronbach's alpha and the criterion validity was assessed by Student's t-test and the Mann-Whitney U-test. RESULTS: The results showed good reliability in the scores for OA, DA, PC and SP domains and a reasonable reliability for the EF domain. The differences between assessors performed by the analysis of variance were not significant. The reliability intra-rater, performed through the test-retest method, showed in all domains high levels of intra-rater correspondence. CONCLUSIONS: The results show the validity and reliability of DSF-84 to young male adults with amputation of the lower limb, being useful for this population. IMPLICATIONS FOR REHABILITATION: In this study have been developed, implemented, and validated an instrument (DSF-84) for assessing the functional and social performance of young male adults with lower limb amputees based on the ICF. The results show the validity and reliability of DSF-84 to young male adults with amputation of the lower limb, being useful for this population.

Efficacy of in-office bleaching techniques combined with the application of a casein phosphopeptide-amorphous calcium phosphate paste at different moments and its influence on enamel surface properties.

OBJECTIVES: The aim of this in vitro study was to investigate the efficacy of in-office bleaching technique combined with the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI Paste-MI) at different moments and its influence on enamel surface properties. METHODS: Eighty bovine dental crowns were randomly allocated into eight groups (n = 10), and bleached with either 35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four different protocols of application of MI were considered: without MI, MI applied before bleaching, MI applied after bleaching, and MI applied both before and after bleaching. Bleaching effectiveness was measured by the VITA EasyShade spectrophotometer utilizing the CIEL*a*b* system (ΔE, ΔL*, Δa*, and Δb*). Color readings were measured at baseline, 7, 14, and 21 days. Hardness and roughness were measured at baseline (T0) and immediately after bleaching (T14). Data were subjected to the two-way ANOVA for repeated measurements and Tukey's test at 5%. RESULTS: HP groups achieved the greatest color change. The application of a CPP-ACP paste did not reduce the efficacy of bleaching peroxides. Samples bleached with CP showed decreased hardness at T14. Samples bleached with HP that received the application of MI before and before/after bleaching did not present hardness decrease at T14. Samples bleached with peroxides only and received MI after bleaching showed increased roughness at T14. CONCLUSIONS: The use of CPP-ACP was able to prevent negative changes in roughness and hardness of bovine enamel when associated to hydrogen peroxide, and might be applied before/after the bleaching protocol.

Enamel properties after tooth bleaching with hydrogen/carbamide peroxides in association with a CPP-ACP paste.

BACKGROUND: This study evaluated the impact of bleaching teeth using blends of a CPP-ACP paste (MI Paste; MI) and carbamide/hydrogen peroxides in different proportions on surface properties of bleached enamel. METHODS: Ninety bovine incisors were bleached with 7.5% hydrogen peroxide (HP), 16% carbamide peroxide (CP), MI and blends of HP or CP:MI at three proportions (1:1, 2:1, 1:2). Hardness and roughness were measured at baseline and after bleaching. Enamel morphology was evaluated by Scanning Electron Microscopy (SEM). The data were analyzed by two-way ANOVA for repeated measurements and Tukey's test. RESULTS: Most of the samples bleached with MI in combination with peroxides presented increased hardness and roughness which were associated to mineral deposition, as observed by SEM images. Blends with higher fractions of MI did not offer superior benefits. CONCLUSIONS: The use of a CPP-ACP paste mixed to carbamide/hydrogen peroxides can decrease adverse side-effects from tooth bleaching on an enamel surface.

Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets.

CONTEXT: The effect of different curing units on bond strength of orthodontic brackets is still unclear when utilizing nanofilled composites in comparison with traditional Transbond-XT. AIM: To evaluate the influence of two adhesive promoters and two curing-light units on the shear bond strength (SBS) of orthodontic brackets. SETTINGS AND DESIGN: The factors under study were adhesive promoters (nanofilled composite - Filtek-Z350 flowable restorative and conventional orthodontic adhesive - Transbond XT) and curing-light units (halogen lamp - Ultralux and LED device - Radii-Call). MATERIAL AND METHODS: Forty lower bovine incisors were utilized. The teeth were distributed in four groups (n = 10) according to the combination between adhesive promoters and curing-light units. Scotchbond Multipurpose-Plus and Transbond-XT primer were used to bond Filtek-Z350 Flowable Restorative and Transbond-XT, respectively. After storage in distilled water for 24 h, the brackets were subjected to SBS test at a speed of 0.5 mm/min until bracket debonding. The Adhesive Remnant Index (ARI) was assigned at fractured specimens. STATISTICAL ANALYSIS USED: Analysis of variance and Tukey test were utilized. The Kruskal-Wallis test was used to compare ARI scores between the groups (p<0.05). RESULTS: There was statistically significant difference between the adhesive promoters tested. Transbond-XT showed higher SBS means than Filtek-Z350. There was no statistically significant difference between both curing-light units tested in this study, neither between ARI scores. CONCLUSIONS: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.

A new model of centrifugal blood pump for cardiopulmonary bypass: design improvement, performance, and hemolysis tests.

A new model of blood pump for cardiopulmonary bypass (CPB) application has been developed and evaluated in our laboratories. Inside the pump housing is a spiral impeller that is conically shaped and has threads on its surface. Worm gears provide an axial motion of the blood column. Rotational motion of the conical shape generates a centrifugal pumping effect and improves pumping performance. One annular magnet with six poles is inside the impeller, providing magnetic coupling to a brushless direct current motor. In order to study the pumping performance, a mock loop system was assembled. Mock loop was composed of Tygon tubes (Saint-Gobain Corporation, Courbevoie, France), oxygenator, digital flowmeter, pressure monitor, electronic driver, and adjustable clamp for flow control. Experiments were performed on six prototypes with small differences in their design. Each prototype was tested and flow and pressure data were obtained for rotational speed of 1000, 1500, 2000, 2500, and 3000 rpm. Hemolysis was studied using pumps with different internal gap sizes (1.35, 1.45, 1.55, and 1.7 mm). Hemolysis tests simulated CPB application with flow rate of 5 L/min against total pressure head of 350 mm Hg. The results from six prototypes were satisfactory, compared to the results from the literature. However, prototype #6 showed the best results. Best hemolysis results were observed with a gap of 1.45 mm, and showed a normalized index of hemolysis of 0.013 g/100 L. When combined, axial and centrifugal pumping principles produce better hydrodynamic performance without increasing hemolysis.

Update on nonsurgical, ultraconservative approaches to treat effectively non-cavitated caries lesions in permanent teeth.

Dental caries on tooth surfaces is still a problem in many industrialized countries. For many years, dentistry was influenced by a mechanical approach characterized by the use of high-speed rotary cutting instruments, and dentists predominantly used surgical methods to address caries. This included radical removal of diseased portions of the tooth, along with material-driven geometric extensions to areas that were assumed to be caries-resistant. This concept of extension for prevention was introduced by G. V. Black and influenced dentists for more than 120 years. Recently, a new paradigm of operative conservatism, sometimes referred to as "minimally invasive dentistry," has gained popularity. This paradigm is designed to promote maximum preservation of healthy dental structures over a lifetime. The aim of this review is to discuss the efficacy of current nonsurgical treatments for non-cavitated caries lesions in permanent teeth. Based on results obtained from clinical trials, this review evaluates treatments such as consumption of CPP-ACP added gums, resin infiltration and fissure sealing. Although in a few cases an invasive approach is needed to arrest caries progression, the non-surgical approach generally provides potential benefits that include conserving structure by delaying intervention or minimizing the operative procedure. All current non-invasive methods are effective in treating non-cavitated caries lesions. The adoption of non-invasive approaches in the management of these lesions can preserve dental tissues, thus increasing tooth longevity.

Preliminary clinical reports of a novel night-guard tooth bleaching technique modified by casein phosphopeptide-amorphous calcium phosphate (CCP-ACP).

Although supervised night-guard bleaching has proved successful for whitening teeth, both mineral loss and tooth sensitivity are still common problems. The present study introduces a novel remineralizer as well as describes the utilization of a possibly low sensitivity supervised night-guard vital tooth bleaching technique. A 22% carbamide peroxide gel was mixed with the casein phosphopeptide-amorphous calcium phosphate-containing MI Paste. The peroxide/MI Paste mixture was prepared with 1 ml of each material until obtaining a homogeneous paste. Five patients were instructed to follow a home bleaching protocol for 3 weeks. The outcome was assessed visually with a Vitapan scale. All subjects presented reduction of at least two Vitapan scale units after bleaching and no sensitivity was reported. The concomitant use of MI Paste and peroxide might not affect the gel effectiveness and still reduce hypersensitivity levels.

An improved method to obtain antigen-excreting Toxocara canis larvae.

Toxocara canis is a dog helminth which causes visceral larva migrans (VLM) when infecting humans as a larva. The infection is demonstrated by detecting IgG antibodies against excretory-secretory larval antigens (ESLA) in serum by ELISA. The production of ESLA involves the collection of adult worms from dog puppy stools, the separation of eggs from dissected uteri, and the in vitro growing of egg-derived larvae, following the time-consuming and laborious protocol described by De Savigny [De Savigny, D.H., 1975. In vitro maintenance of T. canis larvae and a simple method for the production of Toxocara ES antigen for the uses in serodiagnostic tests for visceral larva migrans. Journal of Parasitology 61, 781-782]. In this work, an improved protocol for obtaining T. canis larvae is described. The modifications proposed improved the efficiency of the original De Savigny method in three ways: (i) increasing the parasite yield up to five fold, (ii) improving the larval purity, and (iii) markedly reducing the execution time of the protocol.

Influence of air abrasion and long-term storage on the bond strength of self-etching adhesives to dentin.

This study tested the effects of long-term storage and aluminum oxide air abrasion on the bond strength of self-etching adhesive systems. Extracted human third molars were ground flat with 600-grit SiC paper to expose middle coronal dentin. Clearfil SE Bond and One-Up Bond F were applied to dentin surfaces in accordance with manufacturers instructions with or without previous aluminum oxide 50 microm air abrasion. A crown was built up with the resin composite TPH Spectrum and the specimens were stored in water for 24 hours. The bonded assemblies were vertically sectioned into beams for microtensile bond testing. The beams of each tooth were individually immersed in bottles containing water at 37 degrees C for one day, three and six months; the water was changed daily. The specimens were then subjected to microtensile bond testing. The bond strength data were subjected to ANOVA and Tukey Kramer test. Fractured specimens were analyzed in a scanning electron microscope to determine failure modes. Air abrasion improved Clearfil SE Bond bond strength in the three month evaluation. No significant difference was found between the two adhesives systems, but bond strengths gradually decreased over time. Failure modes varied significantly among groups and were influenced by long-term storage and aluminum oxide air abrasion.