Background concentrations of airborne, culturable fungi and dust particles in urban, rural and mountain regions.

Geographic location and meteorological factors can affect the content of bioaerosol concentrations. This study was conducted to determine the natural background concentrations of culturable fungal spores and dust particles in three different geographical areas. Focus was given to the dominant airborne genera Cladosporium, Penicillium, Aspergillus and the species Aspergillus fumigatus. The influence of weather conditions on the microorganism concentrations in urban, rural and mountain regions were examined. Possible correlations between particle counts and culturable fungal spore concentrations were investigated. 125 measurements of the air were conducted using the air sampler MAS-100NT® and the particle counter Alphasense OPC-N3. The analyses of the collected samples were based on culture methods using different media. The highest median of fungal spore concentrations was detected in the urban region and was of 2.0 × 103 CFU/m3 for xerophilic fungi and 1.7 × 103 CFU/m3 for the genus Cladosporium. The concentrations of fine and coarse particles in rural and urban regions were the highest of 1.9 × 107 pa/m3 and 1.3 × 107 pa/m3, respectively. Little cloud cover and slight wind had a positive influence on the concentration of fungal spores. Furthermore, correlations were observed between air temperature and the concentrations of xerophilic fungi as well as the genera Cladosporium. In contrast, relative humidity correlated negatively with total fungi and Cladosporium and no correlation was found with the other fungi. For the region of Styria in summer and early autumn, the natural background concentration for xerophilic fungi ranged between 3.5 × 102 and 4.7 × 103 CFU/m3 air. No significant differences were detected between the fungal spore concentrations in urban, rural and mountainous regions. The data of this study could be used as a reference to compare the natural background concentrations of airborne culturable fungi in further studies concerning air quality assessment.

A comparison of mount of preparation and finish lines used by dental students in Damascus University and Al Baath University using (CAD/CAM) scanner.

Introduction: Fixed prosthodontics is considered one of the most vital dental treatments that patients receive. Sometimes, however, complication is encountered along with limited information regarding the quality and precision of preparation. Which that led to the conception of this study in order to highlight the shortcomings and obstacles in an attempt to avoid them. This study aims to evaluate the quality of preparation by students of the faculty of dentistry in Damascus University and Al-Baath University by assessing the finish lines. Materials and methods: The specimen of this study consists of 244 prepared abutments divided into two groups: the first group consists of 122 clinically prepared abutments conducted by fifth year students in Damascus University. The second group consists of 122 clinically prepared abutments conducted by fifth year students in Al-Baath University. The specimen also consists of gypsum casts containing replicas of the clinically prepared teeth in addition to the primary casts. All casts - primary casts and post preparation casts - were collected and 3D scans were conducted to each abutment - before and after preparation - and a 3D image was acquired. Statistical analysis was conducted using SPSS v.26 (IBM, USA) with a P-Value of 0.05. Results: The preparation with a simple finishing line at Al-Baath University was 103% greater than it with a statistically significant difference at 56% at Damascus University, by 38%, and the percentage of preparation with a semi-shoulder finish line at Al-Baath University was 5% and at Damascus University was 3% without there being a statistically significant difference Between the two universities, the percentage of preparation with a shoulder finish line in Al-Baath University 14% was lower by a statistically significant difference than in Damascus University 63% by 40% (P < 0.001). Conclusion: The percentage of preparation with a simple finishing line at Al-Baath University was 103% greater than it with a statistically significant difference at 56% at Damascus University, by 38%, and the percentage of preparation with a semi-shoulder finish line at Al-Baath University was 5% and at Damascus University was 3%.

Specific inflammatory osteoclast precursors induced during chronic inflammation give rise to highly active osteoclasts associated with inflammatory bone loss.

Elevated osteoclast (OC) activity is a major contributor to inflammatory bone loss (IBL) during chronic inflammatory diseases. However, the specific OC precursors (OCPs) responding to inflammatory cues and the underlying mechanisms leading to IBL are poorly understood. We identified two distinct OCP subsets: Ly6ChiCD11bhi inflammatory OCPs (iOCPs) induced during chronic inflammation, and homeostatic Ly6ChiCD11blo OCPs (hOCPs) which remained unchanged. Functional and proteomic characterization revealed that while iOCPs were rare and displayed low osteoclastogenic potential under normal conditions, they expanded during chronic inflammation and generated OCs with enhanced activity. In contrast, hOCPs were abundant and manifested high osteoclastogenic potential under normal conditions but generated OCs with low activity and were unresponsive to the inflammatory environment. Osteoclasts derived from iOCPs expressed higher levels of resorptive and metabolic proteins than those generated from hOCPs, highlighting that different osteoclast populations are formed by distinct precursors. We further identified the TNF-α and S100A8/A9 proteins as key regulators that control the iOCP response during chronic inflammation. Furthermore, we demonstrated that the response of iOCPs but not that of hOCPs was abrogated in tnf-α-/- mice, in correlation with attenuated IBL. Our findings suggest a central role for iOCPs in IBL induction. iOCPs can serve as potential biomarkers for IBL detection and possibly as new therapeutic targets to combat IBL in a wide range of inflammatory conditions.

Concentrations of mesophilic bacteria in a poultry farm over two fattening periods focusing on the presence of staphylococci and enterococci.

The increasing animal numbers have a potential impact on the air quality of stables. The aim of this study was to assess the microbial load in the barn air from the day of entry of the chickens to the day of removal for slaughter. A total of 10 measurements in two fattening periods were conducted in a poultry farm with a capacity of 400 chickens in Styria, Austria. The samples were collected with an Air-Sampling Impinger for the investigation of mesophilic bacteria, staphylococci and enterococci. Chicken skin swab samples were collected to detect Staphylococcus aureus. The total colony forming units per cubic meter of mesophilic bacteria of the first measurement series of period I was 7.8 × 104 and increased to 1.4 × 108 at the end and at the fattening period II it increased from 2.5 × 105 to 4.2 × 107. In the measurement series of the fattening period I, the concentration of Staphylococcus spp. increased from 0 to 4.9 × 107 CFUs/m3 and from 0 to 2.1 × 107 CFUs/m3 in the fattening period II. Staphylococcus aureus could not be found on the chicken skin. An interesting finding was the increase of staphylococci while the intestinal enterococci were not detectable in the air of the barn toward the end of both fattening periods.

Multiresistant Bacteria Isolated from Intestinal Faeces of Farm Animals in Austria.

In recent years, antibiotic-resistant bacteria with an impact on human health, such as extended spectrum ß-lactamase (ESBL)-containing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), have become more common in food. This is due to the use of antibiotics in animal husbandry, which leads to the promotion of antibiotic resistance and thus also makes food a source of such resistant bacteria. Most studies dealing with this issue usually focus on the animals or processed food products to examine the antibiotic resistant bacteria. This study investigated the intestine as another main habitat besides the skin for multiresistant bacteria. For this purpose, faeces samples were taken directly from the intestines of swine (n = 71) and broiler (n = 100) during the slaughter process and analysed. All samples were from animals fed in Austria and slaughtered in Austrian slaughterhouses for food production. The samples were examined for the presence of ESBL-producing Enterobacteriaceae, MRSA, MRCoNS and VRE. The resistance genes of the isolated bacteria were detected and sequenced by PCR. Phenotypic ESBL-producing Escherichia coli could be isolated in 10% of broiler casings (10 out of 100) and 43.6% of swine casings (31 out of 71). In line with previous studies, the results of this study showed that CTX-M-1 was the dominant ESBL produced by E. coli from swine (n = 25, 83.3%) and SHV-12 from broilers (n = 13, 81.3%). Overall, the frequency of positive samples with multidrug-resistant bacteria was lower than in most comparable studies focusing on meat products.

Background Concentrations of Cultivable, Mesophilic Bacteria and Dust Particles in the Air in Urban, Rural and Mountain Regions.

Particulate air components can be of anthropogenic or natural origin. It is assumed that in different geographical areas varying concentrations of mesophilic bacteria are present in the ambient air. The aim of this study was to determine the background concentrations of airborne culturable mesophilic bacteria and particulate matter in the ambient air. Furthermore, the association between their concentrations and some environmental factors was analysed. In the period from July to October 2019, concentrations of mesophilic bacteria and dust particles were measured in urban, rural and mountain areas using the single-stage air sampler and the particle counter. The concentrations of bacteria and dust particles in the air were counted as number of Colony Forming Units per cubic metre (CFU/m3) and particles per cubic metre (pa/m3). Staphylococcus sp. were identified. The median values of the cultivated mesophilic bacteria at 30 °C and 37 °C were 7.1 × 102 CFU/m3 and 2.3 × 101 CFU/m3 in mountain regions, 1.3 × 102 CFU/m3 and 6.9 × 101 CFU/m3 in rural regions and 2.1 × 102 CFU/m3 and 6.5 × 101 CFU/m3 in urban regions. The median of Staphylococcus sp. was 2.5 × 100 CFU/m3 in alpine areas and 7.5 × 100 CFU/m3 in urban and rural areas. Higher bacterial concentrations were measured in sunshine and in windy weather. A relationship was observed between the concentrations of airborne mesophilic bacteria and the coarse particles in all three areas. The present study determined values between 5.0 × 100 and 4.6 × 102 CFU/m3 as natural background concentrations of airborne mesophilic bacteria and 1.2 × 107 pa/m3 and 6.5 × 104 pa/m3 for fine and coarse particles, respectively. These results can be proposed as baseline for the assessment of the emission sources of mesophilic bacteria for summer and early autumn.

Correction: Comparative study of impaction and sedimentation in an aerosol chamber using defined fungal spore and bacterial concentrations.

[This corrects the article DOI: 10.1371/journal.pone.0187039.].

Multiresistant Bacteria Isolated from Activated Sludge in Austria.

Wastewater contains different kinds of contaminants, including antibiotics and bacterial isolates with human-generated antibiotic resistances. In industrialized countries most of the wastewater is processed in wastewater treatment plants which do not only include commercial wastewater, but also wastewater from hospitals. Three multiresistant pathogens-extended spectrum ß-lactamase (ESBL)-harbouring Enterobacteriaceae (Gram negative bacilli), methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococci (VRE)-were chosen for screening in a state of the art wastewater treatment plant in Austria. Over an investigation period of six months all three multiresistant pathogens could be isolated from activated sludge. ESBL was the most common resistance mechanism, which was found in different species of Enterobacteriaceae, and in one Aeromonas spp. Sequencing of ESBL genes revealed the dominance of genes encoding members of CTX-M ß-lactamases family and a gene encoding for PER-1 ESBL was detected for the first time in Austria. MRSA and VRE could be isolated sporadically, including one EMRSA-15 isolate. Whereas ESBL is well documented as a surface water contaminant, reports of MRSA and VRE are rare. The results of this study show that these three multiresistant phenotypes were present in activated sludge, as well as species and genes which were not reported before in the region. The ESBL-harbouring Gram negative bacilli were most common.

Comparative study of impaction and sedimentation in an aerosol chamber using defined fungal spore and bacterial concentrations.

Biocontamination control is a very significant part of the manufacturing process of sterile drugs. Sterility is frequently monitored by active or passive air sampling measurements, but there are no specific rules as to how this is to be done. This study tested air sampling methods of active impaction and passive sedimentation under standardized conditions. Aspergillus niger (A. niger) and Staphylococcus aureus (S. aureus) were selected in this experiment to examine parallels, correlations and differences between the two methods. The results show that the number of colony forming units per plate (CFU/plate) was higher for A. niger in the active method, whereas for S. aureus it was higher in the sedimentation method. A high correlation coefficient was found between the impaction and sedimentation methods for A. niger. For S. aureus, depending on the culture media used and the time for passive air sampling, a larger number of CFU/plate was found than in active air sampling. This study concludes that active and passive air sampling can be used for monitoring the air in clean rooms. For fungal spore detection, the impaction is more efficient, as it is possible to sample a higher volume of air in a shorter period of time, whereas the optimal measurement methods for S. aureus depend on a number of factors.

Culturable fungi in potting soils and compost.

In the present study the spectrum and the incidence of fungi in potting soils and compost was investigated. Since soil is one of the most important biotopes for fungi, relatively high concentrations of fungal propagules are to be expected. For detection of fungi, samples of commercial soils, compost and soils from potted plants (both surface and sub-surface) were suspended and plated onto several mycological media. The resulting colonies were evaluated qualitatively and quantitatively. The results from the different sampling series vary, but concentrations on the surface of potted plants and in commercial soils are increased tenfold compared to compost and sub-surface soils. Median values range from 9.5 × 10(4) colony forming units (CFU)/g to 5.5 × 10(5) CFU/g. The spectrum of fungi also varies in the soils. However, all sampling series show high proportion of Aspergillus and Penicillium species, including potentially pathogenic species such as Aspergillus fumigatus. Cladosporium, a genus dominant in the ambient air, was found preferably in samples which were in contact with the air. The results show that potentially pathogenic fungi are present in soils. Immunocompromised individuals should avoid handling soils or potted plants in their immediate vicinity.