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Rômulo Maia de Alencar

Bio: Rômulo Maia de Alencar is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 8 citations.

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Journal ArticleDOI
TL;DR: It is recommended the adoption of a minimum safety distance of more than 2 m and the use of boxes between the dental chairs, as well as a biweekly cleaning of the air-conditioned system and water lines as viable and efficient measures for reduction of the formation and dispersion of fungal aerosols in these environments.
Abstract: This quantitative and qualitative study aimed to evaluate the level of fungal contamination in aerosols dispersed by high rotation pens in dental clinics from Teresina, Piaui, Brazil. The data were collected during the attendance at two dental clinics. Petri dishes containing Sabouraud agar with chloramphenicol were opened for 15 min in the following places: in front of the chair, on the partitions to the right and left of the chair, and in the neighboring workbench. The plates were incubated at room temperature to allow the fungal growth and subsequent species identification. Colonies were formed in 100% of the plaques, accounting for 49 isolates belonging to 19 species, where the most frequent were: Curvularia clavata, Aspergillus niger, Phialemonium obovatum, Curvularia geniculata, and Scopulariopsis koningii. All identified species are pathogenic, and may develop allergic respiratory tract infections and even systemic infections in the patient and the dental surgeon. Our results indicate that the minimum safety distance between the dental chairs defended by the National Sanitary Surveillance Agency is insufficient and that the boxes are an efficient variable to minimize the dispersion of fungal aerosols in the dental environment. Based on these findings, we recommend the adoption of a minimum safety distance of more than 2 m and the use of boxes between the dental chairs, as well as a biweekly cleaning of the air-conditioned system and water lines as viable and efficient measures for reduction of the formation and dispersion of fungal aerosols in these environments.

12 citations


Cited by
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TL;DR: In this paper, the effects of incubation temperature (15, 25, and 37°C) and the type of growth media on fungal index microbial airborne (IMA) in a hospital building were investigated.
Abstract: This study aimed to consider the effects of incubation temperature (15, 25, and 37°C) and the type of growth media on fungal index microbial airborne (IMA) in a hospital building. Because there weren't any integrated guidelines for these variables, the results weren't comparable. Moreover, some studies have investigated the effects of ambient temperature and other factors by the active sampling method. Therefore, we tried to indicate the difference between use of several media and incubation temperature by passive method. Sampling was taken by an open plate during (1hr, 1 m above the ground). Results were shown that IMA was 112–552 CFU/m2/hr., while its highest level was detected in the dialysis ward at 15°C. The predominant fungal species were A.niger and Cladosporium. Besides, the distribution of IMA in indoor air of the hospital was verified base on the Fourier model (R2 = 0.41 and RMSE = 81.65). Moreover, there were significant differences between IMA at various temperatures (p

20 citations

Journal ArticleDOI
03 Aug 2018
TL;DR: This review focuses on waterborne filamentous fungi, unreported from food, that offer a pathogenic potential that are frequently related to soil, air, and food.
Abstract: Clean drinking water and sanitation are fundamental human rights recognized by the United Nations (UN) General Assembly and the Human Rights Council in 2010 (Resolution 64/292). In modern societies, water is not related only to drinking, it is also widely used for personal and home hygiene, and leisure. Ongoing human population and subsequent environmental stressors challenge the current standards on safe drinking and recreational water, requiring regular updating. Also, a changing Earth and its increasingly frequent extreme weather events and climatic changes underpin the necessity to adjust regulation to a risk-based approach. Although fungi were never introduced to water quality regulations, the incidence of fungal infections worldwide is growing, and changes in antimicrobial resistance patterns are taking place. The presence of fungi in different types of water has been thoroughly investigated during the past 30 years only in Europe, and more than 400 different species were reported from ground-, surface-, and tap-water. The most frequently reported fungi, however, were not waterborne, but are frequently related to soil, air, and food. This review focuses on waterborne filamentous fungi, unreported from food, that offer a pathogenic potential.

12 citations

Journal ArticleDOI
TL;DR: In this paper, the authors determined the levels and diversity of microbial aerosol in relation to particle load in five different departments of a dental school clinic and found that the dominant bacteria and fungi were identified as Micrococcus, Bacillus, Streptococcus, Staphylococcus and Penicillium.
Abstract: In the indoor environment of dental clinics, dental staff and patients are exposed to various types of infectious agents transported by aerosols and particles, generated during dental procedures, promoting an increased risk of cross-infection. The aim of this study was to determine the levels and diversity of microbial aerosol in relation to particle load in five different departments of a dental school clinic. The air samples were collected by an active single-stage Andersen sampler during the treatment procedure. The mean concentrations of airborne bacteria were in the range of 52–1030 and 8–844 CFU/m3 at the distances of 0.5 and 2 m, respectively. Bacterial aerosols in pediatric, endodontics, and restorative wards and fungal aerosols in all the sampling wards were significantly higher at the distances of 0.5 m. The dominant bacteria and fungi were identified as Micrococcus, Bacillus, Streptococcus, Staphylococcus, Penicillium, Cladosporium, Aspergillus, Rhizopus, and Alternaria. The positive associations were also obtained between bacteria and fungi levels and particulate matter (PM) concentrations.

5 citations

Journal ArticleDOI
TL;DR: In this paper , a trained dentist performed drilling procedures on a manikin's incisors (teeth nos. 8 and 9) using a high-speed drill and high-volume evacuator.
Abstract: Aerosols are generated routinely during patient care in dentistry. Managing exposure risk requires understanding characteristics of aerosols created during procedures such as those performed using high-speed drills that operate at 200,000 revolutions per minute.A trained dentist performed drilling procedures on a manikin's incisors (teeth nos. 8 and 9) using a high-speed drill and high-volume evacuator. The authors used high-speed imaging to visualize the formation and transport of aerosol clouds and particle sampling to measure aerosol concentration and size distribution at several locations. The authors studied several aerosol mitigation strategies.Aerosols produced during high-speed drilling were erratic and yielded high concentrations that were at least an order of magnitude above baseline. High-speed imaging showed aerosols initially travelled at 1 m per second. Owing to erratic behavior of aerosols, supplemental suction was not effective at collecting all aerosols; however, barriers were effective.Barriers are the most effective mitigation strategy. Other methods studied have limitations and risks. To the authors' knowledge, this article presents the first characterization of aerosols generated during high-speed drilling by a dentist.With thorough preoperative planning and the use of this investigation's findings about effectiveness of mitigation strategies as a guide, dental offices may be able to return to prepandemic productivity.

4 citations

Journal ArticleDOI
TL;DR: A daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes are suggested, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.
Abstract: This quantitative and qualitative study aimed to evaluate the level of fungal contamination in computer keyboards from an Integrated Health Center (IHC) at Piaui, Brazil, and to evaluate the efficacy of 50% sodium bicarbonate and 50% alcoholic vinegar solutions to eliminate these microorganisms. Ten keyboards from six sectors of the IHC were chosen randomly, and the collection was performed in three situations: (i) before of disinfection, (ii) after disinfection with solution of sodium bicarbonate, and (iii) after disinfection with solution of alcoholic vinegar. Samples were inoculated in Petri dishes with dextrose agar potato plus chloramphenicol and incubated at room temperature for 72 h. All keyboards were contaminated with opportunistic fungi, with Cladosporium cladosporioides (29.4%) being the most frequent species, followed by Curvularia lunata (17.6%) and Aspergillus niger, Alternaria alternata, and Curvularia clavata with 11.8% each. The two solutions were proven to be efficient in eliminating fungal contamination; however, the sodium bicarbonate solution caused esthetic damages in keyboards. In addition, this study is the first report of the antifungal activity of alcoholic vinegar in filamentous fungi. Based on our findings, we suggest a daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.

4 citations