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Characterization, pro-inflammatory response and cytotoxic profile of bioaerosols from urban and rural residential settings in Pune, India
2020
Roy, Ritwika | Jan, Rohi | Joshi, Uttara | Bhor, Renuka | Pai, Kalpana | Satsangi, P Gursumeeran
Microbiota associated with airborne particulate matter (PM) is an important indicator of indoor pollution as they can be pathogenic and cause serious health threats to the exposed occupants. Present study aimed to investigate the level of culturable microbes associated with PM and their toxicological characterization in urban and rural houses of Pune city. Highest concentration of bacterial aerosols observed to be associated with PM₁₀ size fraction in urban site (2136 ± 285 CFU/m³) whereas maximum fungal concentration has been measured in rural houses (1521 ± 302 CFU/m³). Predominantly found bacterial species were Bacillus sp., S. aureus, and Pseudomonas aeruginosa and fungal species were Aspergillus sp., Cladosporium sp., and Penicillium sp. in both urban and rural residential premises. Concentration of endotoxin measured using the kinetic Limulus Amebocyte Lysate assay exhibited that the level of endotoxin in both urban and rural sites are associated with household characteristics and the activities performed in indoor as well as outdoor. Cell free DTT assay confirmed the ability of these airborne microbes to induce the production of reactive oxygen species (ROS) varying along with the types of microorganisms. On exposure of A549 cells to airborne microbes, a significant decrease in cell viability was observed in terms of both necrosis and apoptosis pathway. Elevated production of nitric oxide (NO) and proinflammatory cytokines in epithelial cells and macrophages clearly suggest the inflammatory nature of these airborne microbes. Results derived from the present study demonstrated that the indoor air of urban and rural houses of Pune is contaminated in terms of microbial load. Therefore, attention should be paid to control the factors favoring the microbial growth in order to safeguard the health of exposed inhabitants.
Mostrar más [+] Menos [-]Bioburden in sleeping environments from Portuguese dwellings
2021
Viegas, Carla | Dias, Marta | Monteiro, Ana | Faria, Tiago | Lage, Joana | Carolino, Elisabete | Caetano, Liliana Aranha | Gomes, Anita Quintal | Almeida, Susana Marta | Verde, Sandra Cabo | Belo, Joana | Canha, Nuno
A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and after sleeping and bioburden. In addition, and driven by the lack of information regarding fungi azole-resistance in Portuguese dwellings, a screening with supplemented media was also performed. The most prevalent genera of airborne bacteria identified in the indoor air of the bedrooms were Micrococcus (41%), Staphylococcus (15%) and Neisseria (9%). The major indoor bacterial species isolated in all ten studied bedrooms were Micrococcus luteus (30%), Staphylococcus aureus (13%) and Micrococcus varians (11%). Our results highlight that our bodies are the source of the majority of the bacteria found in the indoor air of our homes. Regarding air fungal contamination, Chrysosporium spp. presented the highest prevalence both in after the sleeping period (40.8%) and before the sleeping period (28.8%) followed by Penicillium spp. (23.47% morning; 23.6% night) and Chrysonilia spp. (12.4% morning; 20.3% night). Several Aspergillus sections were identified in air and EDC samples. However, none of the fungal species/strains (Aspergillus sections Fumigati, Flavi, Nidulantes and Circumdati) were amplified by qPCR in the analyzed EDC. The correlations observed suggest reduced susceptibility to antifungal drugs of some fungal species found in sleeping environments. Toxigenic fungal species and indicators of harmful fungal contamination were observed in sleeping environments.
Mostrar más [+] Menos [-]The spatiotemporal distributions and determinants of ambient fungal spores in the Greater Taipei area
2015
Kallawicha, Kraiwuth | Tsai, Ying-Jie | Chuang, Ying-Chih | Lung, Shih-Chun Candice | Wu, Chih-Da | Chen, Tsun-Hsuan | Chen, Pang-Cheng | Chompuchan, Chuphan | Chao, Hsing Jasmine
Airborne fungal spores, a type of bioaerosols, are significant air pollutants. We conducted a study to determine the spatiotemporal distributions of ambient fungi in the Greater Taipei area and develop land use regression (LUR) models for total and major fungal taxa. Four seasonal sampling campaigns were conducted over a year at 44 representative sites. Multiple regressions were performed to construct the LUR models. Ascospores were the most prevalent category, followed by Aspergillus/Penicillium, basidiospores, and Cladosporium. The highest fungal concentrations were found in spring. According to the LUR models, higher concentrations of Aspergillus/Penicillium and basidiospores were respectively present in residential/commercial areas and in areas with shorter road lengths. Various meteorological factors, particulates with aerodynamic diameters of ≤10 μm, and elevation also had significant relationships with fungal concentrations. The LUR models developed in this study can be used to assess spatiotemporal fungal distribution in the Greater Taipei area.
Mostrar más [+] Menos [-]Potentially toxic filamentous fungi associated to the economically important Nodipecten nodosus (Linnaeus, 1758) scallop farmed in southeastern Rio de Janeiro, Brazil
2017
Numerous countries have been confronted with infectious diseases in mariculture activities, including fungi infections, although reports in scallops are scarce. Thus, this study aimed to investigate the occurrence of filamentous fungi in Nodipecten nodosus specimens from three marine farms in Southeastern Brazil. Eight fungi genera were observed in the branchial arches, intestine and muscle tissue of the scallop specimens. These include potentially toxin-producing species, such as Aspergillus, Penicillium and Fusarium. Their presence may lead to potential public health concerns, since all sampling sites showed the presence of fungi in all scallop organs, with special concern regarding edible muscle tissue. A significant number of species was observed at one of the study areas, which could indicate a previously unknown source of contamination, since increases in fungi species richness in polluted coastal waters have been reported. This is also, to the best of our knowledge, the first report of Pestalotiopsis in shellfish.
Mostrar más [+] Menos [-]Airborne molds and mycotoxins in Serpula lacrymans–damaged homes
2014
Pottier, Didier | André, Véronique | Rioult, Jean–Philippe | Bourreau, Alain | Duhamel, Chantal | Bouchart, Valerie Kientz | Richard, Estelle | Guibert, Mathieu | Verite, Philippe | Garon, David
For some years, the degradation of homes by the dry rot fungus Serpula lacrymans increased. This study described, for the first time, the fungal contamination in homes located in Low–Normandy (France) and damaged by Serpula lacrymans. Wood–decaying fungi, airborne molds, fungal species growing on building materials were investigated by cultural and molecular methods. Mycotoxins in the air were quantified by HPLC–MS/MS and the mutagenicity of fungal aerosols was also evaluated using the Ames test. The results showed that Serpula lacrymans was detected in the air for one third of homes with sometimes the co–occurrence of other ligninolytic basidiomycetes species like Donkioporia expansa. Various molds in the air and on materials (117 and 103 species, respectively) were also identified indicating the complexity of indoor mycoflora. Certain recurrent species like Aspergillus versicolor and Penicillium fellutanum were observed both on building materials and in the air. The presence of cellulolytic molds in fungal aerosols and on building materials could be used as an indicator of home degradation. Airborne culturable fungal levels were measured up to 5.8x105 Colony Forming Units (CFU) per cubic meter of the air (CFU/m3) depending on the home. Fungal concentrations also depended on the type of collector (filter or liquid) and were significantly correlated with the median of particles between 2–15μm in size. Two mycotoxins (alternariol and/or ochratoxin A) were observed in 4 homes but no mutagenic activity was found.
Mostrar más [+] Menos [-]Distribution, characterization and health risk assessment of size fractionated bioaerosols at an open landfill site in Dehradun, India
2020
Madhwal, Sandeep | Prabhu, Vignesh | Sundriyal, Sangeeta | Shridhar, Vijay
Open landfilling is a common practice of waste dumping in developing countries, generating a range of environmental and public health hazards. In this study, we determined the distribution, composition and exposure risk of the size-segregated fungal and bacterial bioaerosols in an open landfill site in Dehradun, India. Bioaerosol and particulate matter (PM) measurements were carried out using a six-stage viable Andersen Cascade Impactor and a Wide Range Aerosol Spectrometer, respectively. Pearson correlation analysis was used to determine the relation of bioaerosol concentration with meteorological parameters and PM. The mean concentration of fungal and bacterial aerosols was observed to be 4582.75 ± 1358.25 CFU/m3 and 3609.53 ± 1000.28 CFU/m3, respectively. The bioaerosol composition showed the predominance of potential pathogens including Aspergillus (25.42%), Penicillium (20.34%), Cladosporium (15.25%), Alternaria (13.56%); and gram-negative Bacillus (21.15%), Streptobacillus (17.31%), Coccus (13.46%). Also, an inhalation risk assessment was conducted for the age-specific predictions of bioaerosol and PM deposition in human airways using a multiple path particle dosimetry model. For bioaerosols, maximum submicron depositions in the pulmonary region were observed in adults, while for PM, in children and infants. Finally, to identify the bioaerosol exposure caused respiratory disorders, a questionnaire-based health survey was conducted among the exposed population around the landfill site. The chi-square test showed significantly higher respiratory complaints in females for cold, cough, chest pain and chest tightness than in males. This work highlights the role of bioaerosols and PM in human health disorders in occupational environments associated with waste management.
Mostrar más [+] Menos [-]Evaluation of bio-aerosols type, density, and modeling of dispersion in inside and outside of different wards of educational hospital
2022
Yousefzadeh, Ameneh | Maleki, Afshin | Athar, Saeed Dehestani | Darvishi, Ebrahim | Ahmadi, Manochehr | Mohammadi, Ebrahim | Tang, Van Tai | Kalmarzi, Rasoul Nassiri | Kashefi, Hajar
Exposure to bioaerosols in the air of hospitals is associated with a wide range of adverse health effects due to the presence of airborne microorganisms. Intensity and type of health effects depend on many factors such as the type, density, and diversity of bioaerosols in hospital environments. Therefore, identifying and determining their distribution in hospital environment contribute to reduce their adverse effects and maintain the physical health of patients and staff, as well as find the source of infections and possible allergies due to the presence of bioaerosols. Therefore, the present study was conducted to determine the type and concentration of the bacterial and fungal bioaerosols, and their distribution in the indoor and outdoor air of a teaching hospital to establish a reference for future studies or measures. The air samples were collected with a one-stage Anderson sampler and particle mass counter for a period of four months in the fall and winter of 2019. In total, 262 bacterial and fungal samples were collected from the air of the wards of Tohid Hospital, Sanandaj, Iran. Antibiotic resistance test, bacterial identification by PCR method, and modeling the dispersion of concentrations of bio-aerosols were also conducted. In order to identify bacteria and fungi, some biochemical and molecular tests and microscopic and macroscopic characteristic methods were applied, respectively. The results showed that the highest and lowest densities of the bioaerosols were observed in lung and operating wards (336.67 and 15.25 CFU/m³). Moreover, the highest and least concentrations of particles were seen in the emergency and operating wards, respectively. The most common fungi isolated from the hospital air were Penicillium (24.7%), Cladosporium (23. 4%), Aspergillus niger (13.3%), and Aspergillus Flavus (11.4%). Furthermore, the highest concentration of the isolated bacterium was Staphylococcus hemolyticus (31.84%). Most bacteria showed the highest resistance to gentamicin. The overall average hospital air pollution to bioaerosols was slightly higher than the standards proposed by international organizations. Due to the high concentration of bioaerosols and particles in the studied hospital, providing suitable conditions such as temperature, humidity, proper ventilation, and intelligent air conditioning system using efficient ventilation systems, and restricting the entrance of wards can reduce airborne particles in hospital environment.
Mostrar más [+] Menos [-]Assessing the relationship between airborne fungi and potential dust sources using a combined approach
2022
Tajiki, Forough | Asgari, Hossein Mohammad | Zamani, Isaac | Ghanbari, Farshid
Dust events impose negative socio-economic, health, and environmental impacts on vulnerable areas and reflect their sources’ physiochemical and biological characteristics. This study aimed to assess the impact of two dust sources on the concentration and diversity of airborne fungi in one of the dustiest areas in the world. This study is the first attempt to investigate the relationship between dust sources fungal community and those in airborne dust. Also, the contribution of dust sources to airborne fungi was estimated. Air masses arriving at the study area were assessed using local wind rose and the HYSPLIT model. Sampling was carried out from airborne dust at the Arvand Free Zone as target areas and soil in the dried parts of the Hor al-Azim and Shadegan wetlands as source areas to explore the relationship between fungi in the dust sources and the downwind area. The samples were analyzed in the lab to extract DNA. The internal transcribed spacer (ITS) regions of the rDNA gene were amplified using the primers ITS1F and ITS4, and then PCR products were sent to the lab for sequencing. The raw DNA data were processed using the QIIME virtual box to pick operational taxonomic units and taxonomy assignments. The most common fungi at the genus level were in the order of Penicillium > Aspergillus > Alternaria > Fusarium > Paradendryphiella > Talaromyces. The similarity between air and soil fungal genera was investigated using richness and diversity indices, the phylogenetic tree, and principal component analysis. The results showed that the community structures of ambient fungi in the Hor al-Azim and Shadegan dust sources were more similar to those on dusty days than non-dusty days. The source tracker model was used to quantify the contributions of known dust sources to airborne fungi. The results showed that the main source of airborne fungi was Hor al-Azim on dusty and non-dusty days. This study’s results can help managers identify and prioritize dust sources regarding fungal species.
Mostrar más [+] Menos [-]Bioaugmentation and Biostimulation of Total Petroleum Hydrocarbon Degradation in a Petroleum-contaminated Soil with Fungi Isolated from Olive Oil Effluent
2019
Essabri, Abduelbaset M. A. | Aydinlik, Nur Pasaoglulari | Williams, Ndifreke Etuk
In degradation of total petroleum hydrocarbon, 35 isolates belonging to 11 genera were sanitized and 3 isolates as well as their consortium were initiated to be able to raise in association with petroleum hydrocarbon as sole source of carbon under in vitro circumstances. The isolated strains were grounded on internal transcribed spacer (ITS) rDNA sequence analysis. The fungal strains with the utmost potentiality to reduce petroleum hydrocarbon without emerging antagonistic activities were Aspergillus niger, Penicillium ochrochloron, and Trichodema viride. For fungal growth on petroleum hydrocarbon, P. ochrocholon gained weight of 44%, A. niger 49%, and T. viride 39% within the first 30–40 days. As compared to the controls, these fungi accumulated significantly higher biomass, produced extracellular enzymes, and degraded total petroleum hydrocarbon and A. niger strongly degraded total petroleum hydrocarbon with a degradation of about 71.19%. These observations with GC-MS data confirm that these isolates displayed rapid total petroleum hydrocarbon biodegradation within a period of 60 days and the half-life showed that A. niger was the shortest with t1/2 = 21.280 day⁻¹ corresponding to the highest percent degradation of 71.19% and first-order kinetic fitted into the present study. By multivariate analysis, five main factors were identified by factor analysis (FA). The first factor (F1) of the fungi species accounts for 20.0% which signifies that fungi species controls the degradation of petroleum variability and hierarchical cluster analysis (HCA) as a dendrogram with five observations and three variables shows two predominant clusters order cluster 1 > 2.
Mostrar más [+] Menos [-]Fungal populations in the bedroom dust of children in Havana, Cuba, and its relationship with environmental conditions
2021
Sánchez Espinosa, Kenia C. | Rojas Flores, Teresa I. | Davydenko, Sonia Rodríguez | Venero Fernández, Silvia J. | Almaguer, Michel
The study of the fungal community composition in house dust is useful to assess the accumulative exposure to fungi in indoor environments. The objective of this research was to characterize the fungal diversity of house dust and its association with the environmental conditions of bedrooms. For this, the dust was collected from 41 bedrooms of children between the ages of 8 and 9 with a family history of asthma, residents of Havana, Cuba. The fungal content of each sample was determined by two methods: plate culture with malt extract agar and by direct microscopy. An ecological analysis was carried out from the fungal diversity detected. To describe the factors associated with the fungi detected, bivariate logistic regression was used. Through direct microscopy, between 10 and 2311 fragments of hyphae and spores corresponding mainly to Cladosporium, Coprinus, Curvularia, Aspergillus/Penicillium, Xylariaceae, and Periconia were identified. Through the culture, 0–208 CFU were quantified, where Aspergillus, Cladosporium, and Penicillium predominated. The culturability evidenced the differences between the quantification determined by both methods. A positive relationship was found between the type of cleaning of the furniture, the presence of trees in front of the bedroom, indoor relative humidity, indoor temperature, the presence of air conditioning, and natural ventilation with specific spore types and genera. The use of two different identification methods allowed to detect a greater fungal diversity in the residences evaluated. Monitoring the exposure to these fungal allergens in childhood can help to prevent sensitization in the allergic child, the development of asthma, and other respiratory diseases.
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