Cloud condensation nuclei activity of internally mixed particle populations at a remote marine free troposphere site in the North Atlantic Ocean.

This study reports results from research conducted at the Observatory of Mount Pico (OMP), 2225 m above mean sea level on Pico Island in the Azores archipelago in June and July 2017. We investigated the chemical composition, mixing state, and cloud condensation nuclei (CCN) activities of long-range transported free tropospheric (FT) particles. FLEXible PARTicle Lagrangian particle dispersion model (FLEXPART) simulations reveal that most air masses that arrived at the OMP during the sampling period originated in North America and were highly aged (average plume age > 10 days). We probed size-resolved chemical composition, mixing state, and hygroscopicity parameter (κ) of individual particles using computer-controlled scanning electron microscopy with an energy-dispersive X-ray spectrometer (CCSEM-EDX). Based on the estimated individual particle mass from elemental composition, we calculated the mixing state index, χ. During our study, FT particle populations were internally mixed (χ of samples are between 53 % and 87 %), owing to the long atmospheric aging time. We used data from a miniature Cloud Condensation Nucleus Counter (miniCCNC) to derive the hygroscopicity parameter, κCCNC. Combining κCCNC and FLEXPART, we found that air masses recirculated above the North Atlantic Ocean with lower mean altitude had higher κCCNC due to the higher contribution of sea salt particles. We used CCSEM-EDX and phase state measurements to predict single-particle κ (κCCSEM-EDX) values, which overlap with the lower range of κCCNC measured below 0.15 % SS. Therefore, CCSEM-EDX measurements can be useful in predicting the lower bound of κ, which can be used in climate models to predict CCN activities, especially in remote locations where online CCN measurements are unavailable.

Effect of high-fluoride dentifrice on root dentine de-remineralization exposed to erosion challenge in vitro.

Background: High-fluoride dentifrice can be used to manage dental erosion; however, little is known about it effect on root dentine previously demineralized. This study evaluated the effect of high-fluoride treatment on dentin de/remineralization exposed to an erosion challenge in vitro. Material and Methods: Sound and demineralized dentine blocks were submitted to a 5-days-erosive challenge in soft drink (4/day during 90 s) and treated with fluoride solutions (0, 1,100, or 5,000 µg F/mL). After this, the percentage of surface hardness loss (%SHL) or recovery (%SHR) was calculated. Data were analyzed by one-way ANOVA and Tukey post hoc test with p fixed at 5%. Results: High-fluoride treatment was able to reduce dentine remineralization and increase mineral recovery of previously demineralized dentine compared to other treatments tested (p<0.05). Conclusions: High-fluoride treatment was able to increase the remineralization and reduce the demineralization of root dentine submitted to an erosive challenge in vitro, being an option for the erosion prevention/treatment. Key words:Fluorides, root caries, tooth erosion, toothpastes.

Effect of high-fluoride dentifrice and bracket bonding composite material on enamel demineralization adjacent to orthodontic brackets in vitro.

BACKGROUND: There is a lack of information about the association of high-fluoride dentrifrice and fluoride-containing bonding material to prevent enamel white spot lesions development adjacent to brackets. The aim of this in vitro study was to evaluate the effect of high-fluoride dentifrice and fluoride-containing bonding material on enamel demineralization adjacent to orthodontic brackets. MATERIAL AND METHODS: Forty-eight enamel specimens with 7x7x2 mm were obtained from bovine incisors. Orthodontic brackets were bonded with fluoride-containing resin composite (OrthoCem®) or fluoride-free low viscosity resin. The specimens were submitted to an 8-day pH cycling that consisted in the daily immersion of specimens in the demineralizing solution for 4 h and in artificial saliva for 20 h in an incubator at 37° C. The treatments consisted in 5 min-immersion between the cycles of fluoride (F) suspensions containing 275 µg F/mL, 1,250 µg F/mL or distilled water (negative control). The 275 and 1,250 µg F/mL concentrations were used to simulate salivary dilution of 1,100 and 5,000 µg F/g dentifrices during toothbrushing. After the experiment, cross-sectional hardness was performed to analyze the lesion area of the specimens. Tukey post hoc test after two-way ANOVA with p at 5% was used as statistical analysis. RESULTS: The specimens treated with high-fluoride dentifrice showed significantly less demineralization in comparison with the other treatments (p>0.05). There was a significant difference in the cross-sectional hardness values for the specimens bonded with OrthoCem when compared to the low viscosity resin (p>0,05). CONCLUSIONS: The use of high-fluoride dentifrice associated with fluoride-containing bonding material promoted a greater reduction of enamel demineralization adjacent to orthodontic brackets. Key words:Demineralization, dentifrice, fluoride, bonding materials, orthodontic brackets.

Development of Chlorhexidine Digluconate and Lippia sidoides Essential Oil Loaded in Microemulsion for Disinfection of Dental Root Canals: Substantivity Profile and Antimicrobial Activity.

The dental intracanal disinfection is crucial to achieve the success of endodontic treatment, avoiding the maintenance of endodontic infections. Chlorhexidine digluconate can act as an irrigating agent for it. However, it can cause tissue irritation in high concentrations. Therefore, combinations with other antimicrobial agents and more efficient therapeutic alternatives are studied, which make it possible to administer drugs more safely and with minimal adverse effects. Thus, the objective of this study was the development of a microemulsion containing chlorhexidine digluconate and essential oil of Lippia sidoides to be used for disinfection of dental root canals and to evaluate its profile of substantivity and antimicrobial activity. The microemulsions were obtained through phase diagrams, using the spontaneous formation method. We completed a physical-chemical characterization and evaluate the stability of the microemulsions, in addition to the substantivity profile in a bovine root dentin model, and in vitro antibacterial effect on Enterococcus faecalis. A method for quantifying chlorhexidine was developed using UV-Vis spectroscopy. The microemulsions showed acid pH, conductivity above 1.3 µScm-1, and dispersion index similar to water. The microemulsions showed antimicrobial inhibition halos similar to the commercial gel conventionally used, but with four times more substantivity to dentinal tissues. Microemulsions were obtained as a therapeutic alternative to formulations available on the market, presenting themselves as a system with great potential for the administration of drugs for disinfection of root canals.

Extensive Soot Compaction by Cloud Processing from Laboratory and Field Observations.

Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models.

Wet deposition of particulate carbon to the Central North Atlantic Ocean.

Elemental carbon (EC) and water-insoluble organic carbon (WIOC) concentrations were measured in wet-only precipitation samples collected on Terceira Island (Azores, Portugal) between December 2009 and October 2010, to investigate temporal variations, source regions and wet deposition fluxes. The global volume-weighted average (vwa) concentrations were 134 ± 19 µgC L(-1) for WIOC and 15.0 ± 1.6 µgC L(-1) for EC, which fall within the range of values that have been found in the European background atmosphere. The WIOC concentration exhibited a temporal variation over the study period with a minimum in winter (vwa 88 ± 16 µgC L(-1)) and a maximum in summer (vwa 477 ± 86 µgC L(-1)). This trend was due to the higher dilution effect of winter rains and possibly to an increase of biogenic particulate carbon incorporation during the growing season. A different temporal variation was observed for the EC concentration with a minimum in summer (vwa 4.2 ± 3.3 µgC L(-1)) and a maximum in spring (vwa 17.5 ± 2.2 µgC L(-1)). The observed trend was mainly related to changes in atmospheric circulation patterns over the Azores. A backward trajectory analysis was applied to identify possible source regions of particulate carbon. The highest WIOC and EC concentrations were associated with air masses that persisted for more than four days over the Central North Atlantic Ocean and with air masses arriving from Europe, respectively. Lower concentrations were observed in samples collected under the influence of back-trajectories from North America. Despite the lower abundance of particulate carbon, the wet deposition fluxes were higher for this group of samples, which reflects the higher amount of precipitation that is normally associated with air masses arriving in the Azores from the west and northwest sectors.

Idosos com acidente vascular encefálico isquêmico: caracterização sociodemográfica e funcional / Elderly with ischemic stroke: social-demographic and functional characterization

Objetivou-se descrever as características sociodemográficas e funcionais do idoso após o acidente vascular encefálico isquêmico. Estudo descritivo, quantitativo, realizado com amostra de acessibilidade de 52 idosos acometidos por acidente vascular encefálico isquêmico, em serviço de saúde de Fortaleza-CE-Brasil, entre maio e agosto de 2009. Calcularam-se média e desvio padrão para as variáveis contínuas e teste qui-quadrado para comparar proporções nas variáveis categóricas. Os resultados mostraram que 37 (71,2%) estavam entre 60 e 79 anos de idade, 43 (82,7%) residiam em Fortaleza, 30 (57,7%) eram casados, com renda familiar média de 2,5 salários mínimos e 16 (30,8%) tinham histórico da doença na família. A proporção de idosos se distribuiu de maneira uniforme nas faixas de incapacidade funcional e de dependência (p=0,972 e p=0,780). O conhecimento do perfil desses idosos é fundamental, pois a qualidade de vida destes tem estreita ligação com a realidade social e econômica, bem como a capacidade funcional.

Chromoblastomycosis: a clinical and molecular study of 18 cases in Rio de Janeiro, Brazil.

BACKGROUND: Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by dematiaceous fungi. METHODS: We described epidemiological data, clinical presentation, and treatment of 18 cases of CBM diagnosed in Rio de Janeiro, Brazil. Diagnosis was obtained by mycological, histopathological findings demonstrating typical muriform cells with confirmation of isolated by DNA sequencing of the ribosomal internal transcribed spacer. RESULTS: The majority of patients were male (72.2%) ranging from 39 to 83 years old, farm laborers and construction workers. The duration of disease varied from four months to 32 years. The most common presentations were verrucous form in ten (55.6%) patients, followed by tumoral in three (16.7%) patients, primarily of moderate (55.6%) and severe (38.9%) intensity. Lower (44.4%) and upper limbs (33.3%) were the most affected sites. Fonsecaea pedrosoi isolated from 14 (77.8%), and Cladophialophora carrionii isolated from one case (5.6%). Fifteen patients (83.3%) were treated. Six patients (40%) received oral itraconazole 200-400 mg/day, five patients (33.3%) received oral itraconazole 200-400 mg/day combined with fluconazole 200 mg/day, and four (26.7%) patients were submitted to surgery. The duration of therapy varied from 12 to 48 months. Cure rate was 80% (12/15). No relapse was observed after two years of follow-up. CONCLUSIONS: Success was due to attending a center with specialized clinical care, laboratory support, and pharmaceutical care.

Cladophialophora carrionii: a rare agent of chromoblastomycosis in Rio de Janeiro State, Brazil.

A 73 year-old male farm laborer from a rural area presented a 15 year history of extensive tumoral lesions over his left leg. Histological studies of skin biopsy showed pseudoepitheliomatous hyperplasia and granulomatous chronic inflammatory process with muriform cells, confirming chromoblastomycosis (CBM). Cladophialophora carrionii was isolated in culture. Treatment with itraconazole 400 mg/day for 12 months resulted in complete remission of lesions. As far we aware, this is the first case report of CBM caused by Cladophialophora carrionii in Rio de Janeiro State, Brazil.

Cladophialophora carrionii: a rare agent of chromoblastomycosis in Rio de Janeiro State, Brazil / Cladophialophora carrionii: agente raro de cromoblastomicose no estado do Rio de Janeiro, Brasil

A 73 year-old male farm laborer from a rural area presented a 15 year history of extensive tumoral lesions over his left leg. Histological studies of skin biopsy showed pseudoepitheliomatous hyperplasia and granulomatous chronic inflammatory process with muriform cells, confirming chromoblastomycosis (CBM). Cladophialophora carrionii was isolated in culture. Treatment with itraconazole 400 mg/day for 12 months resulted in complete remission of lesions. As far we aware, this is the first case report of CBM caused by Cladophialophora carrionii in Rio de Janeiro State, Brazil.

Lavrador, com 73 anos, residente em área rural apresentava há 15 anos lesões tumorais disseminadas na perna esquerda. Exame histopatológico de biópsia de pele mostrou hiperplasia pseudo-epiteliomatosa e processo inflamatório crônico granulomatoso com células muriformes, confirmando o diagnóstico de cromoblastomicose (CBM). Cladophialophora carrionii foi isolado na cultura. Tratamento com itraconazol 400 mg/dia durante 12 meses resultou na completa remissão das lesões. Este é o primeiro relato de CBM causado por C. carrionii no estado do Rio de Janeiro, Brasil.