scholarly journals Legionella Detection in Water Networks as per ISO 11731:2017: Can Different Filter Pore Sizes and Direct Placement on Culture Media Influence Laboratory Results?

2020 ◽  
Vol 17 (6) ◽  
pp. 2077
Author(s):  
Osvalda De Giglio ◽  
Giusy Diella ◽  
Paolo Trerotoli ◽  
Michela Consonni ◽  
Roberta Palermo ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Culture Media ◽  
Experimental Studies ◽  
Culture Technique ◽  
Environmental Surveillance ◽  
Water Networks ◽  
National Guidelines ◽  
Pore Sizes ◽  
Standard Culture ◽  
Membrane Porosity

Determination of Legionella concentrations in water networks is useful for predicting legionellosis risks. The standard culture technique using concentration with membranes filters is the most commonly used method for environmental surveillance of Legionella. The aim of this study was to verify whether filtration with different filter pore sizes (0.2 and 0.45 µm) according to (ISO) 11731:2017, followed by directly placing them on culture media, can influence Legionella detection. Three laboratories participated in an experimental study that tested a known suspension of Legionella pneumophila (Lpn) serogroup 1 (ATCC 33152) (approximate final cell density of 15 CFU/mL). E. coli (ATCC 11775) and Pseudomonas aeruginosa (ATCC 25668) were included as control tests. The average (95% CI) percentage of recovery of Lpn was 65% using 0.45-µm filters and 15% using 0.2-µm filters (p < 0.0001). For control tests, the average (95% CI) percentage of recovery was higher with 0.45 vs. 0.2 µm filters: 97% vs. 64% for Escherichia coli (p < 0.00001) and 105% vs. 97% (p = 0.0244) for P. aeruginosa. Our results showed that the 0.45-µm filters provided the greatest detection of Legionella. Because the current national guidelines leave the choice of membrane porosity to the operator, experimental studies are important for directing operators towards a conscious choice to standardize Legionella environmental surveillance methods.

scholarly journals How Molecular Typing Can Support Legionella Environmental Surveillance in Hot Water Distribution Systems: A Hospital Experience

2020 ◽  
Vol 17 (22) ◽  
pp. 8662
Author(s):  
Luna Girolamini ◽  
Silvano Salaris ◽  
Jessica Lizzadro ◽  
Marta Mazzotta ◽  
Maria Rosaria Pascale ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Molecular Typing ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Gene Sequencing ◽  
Culture Technique ◽  
Hot Water ◽  
Environmental Surveillance ◽  
Risk Map

In this study, we aimed to associate the molecular typing of Legionella isolates with a culture technique during routine Legionella hospital environmental surveillance in hot water distribution systems (HWDSs) to develop a risk map able to be used to prevent nosocomial infections and formulate appropriate preventive measures. Hot water samples were cultured according to ISO 11731:2017. The isolates were serotyped using an agglutination test and genotyped by sequence-based typing (SBT) for Legionella pneumophila or macrophage infectivity potentiator (mip) gene sequencing for non-pneumophila Legionella species. The isolates’ relationship was phylogenetically analyzed. The Legionella distribution and level of contamination were studied in relation to temperature and disinfectant residues. The culture technique detected 62.21% of Legionella positive samples, characterized by L. pneumophila serogroup 1, Legionella non-pneumophila, or both simultaneously. The SBT assigned two sequence types (STs): ST1, the most prevalent in Italy, and ST104, which had never been isolated before. The mip gene sequencing detected L. anisa and L. rubrilucens. The phylogenetic analysis showed distinct clusters for each species. The distribution of Legionella isolates showed significant differences between buildings, with a negative correlation between the measured level of contamination, disinfectant, and temperature. The Legionella molecular approach introduced in HWDSs environmental surveillance permits (i) a risk map to be outlined that can help formulate appropriate disinfection strategies and (ii) rapid epidemiological investigations to quickly identify the source of Legionella infections.

scholarly journals Environmental Surveillance of Legionella spp. in an Italian University Hospital Results of 10 Years of Analysis

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2304
Author(s):  
Giovanna Deiana ◽  
Antonella Arghittu ◽  
Marco Dettori ◽  
Maria Dolores Masia ◽  
Maria Grazia Deriu ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Distribution Systems ◽  
Water Distribution ◽  
Linear Trend ◽  
Water Distribution Systems ◽  
University Hospital ◽  
Environmental Surveillance ◽  
National Guidelines ◽  
Increased Risk ◽  
Definitive Method

The occurrence of Legionella spp. in the water distribution systems of large hospitals and other healthcare facilities is considered particularly dangerous, due to the critical nature of the hospitalized patients. The aim of this study is to present a pluri-annual environmental surveillance in a large university hospital assessing the prevalence of Legionella spp. and underlining its variability over the years. The samples of water were collected in accordance with the Italian National Guidelines and the sampling sites considered in this study were selected favoring wards with very high-risk patients and with patients at increased risk. The laboratory analyzed a total of 305 water samples deriving from 24 different sampling points. Legionella spp. were detected in 39.4% of samples, the majority of which were contaminated by Legionella pneumophila serogroups 2–14 (68.7%). Statistically significant differences were found among different seasons with a linear trend in positive proportion from summer to spring. Several experimental interventions to prevent and reduce Legionella colonization were attempted, but there is no a definitive method for the complete eradication of this microorganism. The permanent monitoring of hospital water distribution systems is fundamental to preventing the potential risk of nosocomial Legionellosis and to implementing procedures to minimize the risk of Legionella spp. colonization.

Croissance et fructification de Ceratocystis spp. avec attention particulière à C. piceae et C. fimbriata, en fonction du substrat

1982 ◽  
Vol 60 (4) ◽  
pp. 358-363
Author(s):  
A. Thuillier ◽  
P. Neumann
Keyword(s):  
Nutrient Solution ◽  
Culture Media ◽  
Basal Medium ◽  
Malt Agar ◽  
Fruiting Bodies ◽  
Ceratocystis Fimbriata ◽  
Good Production ◽  
Wood Extracts ◽  
Standard Culture ◽  
Better Than

Ceratocystis coerulescens, C. fimbriata, C. ips, and C. minor were tested for production of sexual fruiting bodies, and C. penicillata and C. piceae for asexual fruiting bodies. Ceratocystis fimbriata produced perithecia easily on standard culture media, but there were marked differences between the two strains tested (503, 560). Strain 503 had a good production of fruiting bodies on malt agar (M) and a basal nutrient solution (N). Strain 560 fared better than 503 on Leonian agar (L), but did not fructify on M and N. Supplementing media with various wood extracts produced better results. M + maple sapwood extracts and L + poplar sapwood extracts gave the best results with strain 503, and L + pine sapwood extracts was the best with strain 560.Production of coremia was also influenced by the basal medium and the kind of extracts added as supplements. Fir and maple extracts stimulated the production of fruiting bodies, whereas pine and poplar extracts had no or very little stimulating effects. In every other species tested, the production of fruiting bodies was none or very irregular. [Journal translation]

Experimental studies on Lecanora rupicola (L.) Zahlbr.: chemical and microscopical investigations of the mycobiont and re-synthesis stages

2006 ◽  
Vol 38 (6) ◽  
pp. 577-585 ◽  
Author(s):  
Georg BRUNAUER ◽  
Armin HAGER ◽  
Wolf Dietrich KRAUTGARTNER ◽  
Roman TÜRK ◽  
Elfie STOCKER-WÖRGÖTTER
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sequence Data ◽  
Experimental Studies ◽  
Culture Conditions ◽  
Voucher Specimen ◽  
Dna Sequence Data ◽  
Standard Culture ◽  
Voucher Specimens ◽  
Scanning Electron

Culture experiments that trigger the axenically grown mycobionts of Lecanora rupicola to produce the polyketide chemosyndrome typical of the naturally grown lichen are reported. This chemosyndrome comprises lecanoric, haematommic and orsellinic acids, sordidone, eugenitol and atranorin, all of which were hardly produced under standard culture conditions. The only exception was arthothelin that was only present in the voucher specimen. It has been shown that almost the complete acetyl-polymalonyl-pathway leading to depsides and chromones can be induced in culture, but apparently not the xanthones. The mycobiont was also successfully re-synthesized with its original photobiont, as confirmed by Scanning Electron Microscope studies (SEM). Cultures of the resynthesised lichen biosynthesized additional satellite substances, which were not detected either in the voucher specimens or in the aposymbiontically (without the photobiont) grown mycobiont cultures. The identity of cultured mycobionts of L. rupicola was confirmed by comparing ITS-DNA-sequence data from the original lichen with publicly available (GeneBank) sequences of that species.

scholarly journals The effect of Malaysian stingless bee, Trigona spp. honey in promoting proliferation of the undifferentiated stem cell

2019 ◽  
pp. 10-19 ◽  
Author(s):  
Mohd Amin Marwan Mohamad ◽  
Muhammad Alif Mazlan ◽  
Muhammad Ibrahim ◽  
Afzan Mat Yusof ◽  
Shamsul Azlin Ahmad Shamsuddin ◽  
...  
Keyword(s):  
Stem Cells ◽  
Culture Media ◽  
Proliferative Effect ◽  
Natural Medicine ◽  
Ability To Regenerate ◽  
Potential Applications ◽  
Standard Culture ◽  
The Stability ◽  
Dose Dependent ◽  
Standard Culture Medium

Stem cells provide various potential applications in regenerative medicine through its ability of self-renewal and differentiation. Among the various stem cells, dental pulp stem cells (DPSCs) have shown encouraging results in their ability to regenerate. Honey has been used in traditional culture as a natural medicine in supporting wound healing. Yet, very few studies on honey were conducted for its potential as a proliferative agent for stem cells. The aim of this study is to evaluate the stability of two Trigona spp. honeys (1 and 2) added in culture media and its proliferative effect on DPSCs. Both honeys were diluted with standard culture medium through dilution process to prepare the concentrations of 0.01%, 0.04%, 0.10% and 0.25%. DPSCs were treated with the diluted honeys for 24 hours. The proliferative activity was determined through the images taken using an inverted microscope for every six hours. In addition, the MTT assay was conducted to determine the cell viability of DPSCs when treated with both honey 1 and 2 at various concentrations. The results showed a stable culture media added with honey for three days and a dose-dependent proliferative effect of both Trigona spp. honey samples on DPSCs. Optimum proliferative effects were observed at 24 hours for both Trigona spp. honey 1 and 2 on DPSCs. The optimum concentration of Trigona spp. honey 1 was from 0.04% to 0.10% and Trigona spp. honey 2 was below 0.01%. It is concluded that Trigona spp. honey has a promising proliferative effect on DPSCs.

scholarly journals Effect of some species of bacteria on viability of human hydatid cysts

2010 ◽  
Vol 7 (3) ◽  
pp. 1153-1158
Author(s):  
Baghdad Science Journal
Keyword(s):  
Bacterial Infections ◽  
Public Hospital ◽  
Culture Media ◽  
Cell Activity ◽  
Culture Technique ◽  
Hydatid Cysts ◽  
Streptococcus Pneumonia ◽  
Hydatid Fluid ◽  
Negative Culture ◽  
Biliary Ducts

A total of 50 fertile human hydatid cases {33(66%) females and (34%) males}, obtained from Al-Ramadi public Hospital during the period from December 2003 to July 2004 were examined to study any bacterial infections. The specimens were obtained from hydatid fluid and then cultured on appropriate culture media to distinguish some species of bacteria which resulted in obtaining: Staphylococcus aureus (18%), Pseudomonas aeruginosa(12%), Escherichia coli(6%) and Streptococcus pneumonia (4%). These bacteria were confirmed by isolation from interacyst fluid and blood culture technique. The possible routs of infection may be through blood, biliary ducts and bronchioles .The selectivity permeable of the cyst wall may be absent and that may allow some species of bacteria to enter inside the cyst. Further, the percent viability decreased among cyst which yielded S. aureus , P. aeruginosa and other bacteria isolated after culturing compared with those of negative culture .Besides, the two types of protoscoleces motilities (flame cell activity and constriction –relaxation movement )increased in cases of negative culture .This association holds true at three different temperature (25ºC,37ºC and 40ºC).

scholarly journals Application of Flow Cytometry to Segregated Kinetic Modeling Based on the Physiological States of Microorganisms

2007 ◽  
Vol 73 (12) ◽  
pp. 3993-4000 ◽  
Author(s):  
Covadonga Quir�s ◽  
M�nica Herrero ◽  
Luis A. Garc�a ◽  
Mario D�az
Keyword(s):  
Flow Cytometry ◽  
Culture Media ◽  
Glucose Consumption ◽  
Viable Cell ◽  
Counting Method ◽  
Batch Cultures ◽  
Viable Cells ◽  
The Status ◽  
Standard Culture

ABSTRACT Flow cytometry (FC) has been introduced to characterize and to assess the physiological states of microorganisms in conjunction with the classical plate-counting method. To show the applicability of the technique, in particular for the development of kinetic models, pure culture fermentation experiments were followed over time, using both prokaryotic (Lactobacillus hilgardii) and eukaryotic (Saccharomyces cerevisiae) microorganisms growing in standard culture media (MRS and YPD). The differences observed between the active and viable cells determined by FC and CFU, respectively, allowed us to determine that a large number of cells were in a viable but nonculturable (VBNC) state, which resulted in a subpopulation much larger than the damaged-cell (double-stained) subpopulation. Finally, the determination of the evolution of viable, the VBNC, and the dead cells allowed us to develop a segregated kinetic model to describe the yeast and the bacteria population dynamics and glucose consumption in batch cultures. This model, more complete than that which is traditionally used, based only on viable cell measurements, describes better the behavior and the functionality of the cultures, giving a deeper knowledge in real time about the status and the course of the bioprocesses.

Modern H1- antihistamines in the treatment of allergic rhinitis: focus on bilastine

2021 ◽  
Vol 18 (2) ◽  
pp. 66-76
Author(s):  
Alexander V. Emelyanov ◽  
Galina R. Sergeeva ◽  
Evgenia V. Leshenkova
Keyword(s):  
Allergic Rhinitis ◽  
Experimental Studies ◽  
Hepatic Metabolism ◽  
Rapid Onset ◽  
Perennial Allergic Rhinitis ◽  
National Guidelines ◽  
Duration Of Action ◽  
Ocular Symptoms ◽  
H1 Antihistamines ◽  
Adults And Children

The second generation of H1-antihistamines is approved for the stepwise treatment of seasonal and perennial allergic rhinitis in adults and children by international and national guidelines. They reduce the severity of nasal and ocular symptoms of rhinitis and improve the quality of life of patients. Bilastine, a piperidine derivative, is a novel H1-antihistamine. It has a potent and selective effect on H1- receptors and a rapid onset and long duration of action and substantially reduces nasal and ocular symptoms of seasonal and perennial allergic rhinitis. Bilastine has no clinically substantial hepatic metabolism and has a high safety profile: it has no sedative effect, does not affect cognitive functions, has no cardiotoxic effects, and does not interact with alcohol and benzodiazepines in normal and high doses. Tachyphylaxis does not develop despite long-term (up to 1 year) use. Bilastine is registered for clinical use in adults and children aged 12 years. The results of clinical and experimental studies have demonstrated that bilastine has many of the features of modern H1-antihistamines recommended by international guidelines.

scholarly journals Human chronic myelogenous leukemia cell-line with positive Philadelphia chromosome

Blood ◽  
1975 ◽  
Vol 45 (3) ◽  
pp. 321-334 ◽  
Author(s):  
CB Lozzio ◽  
BB Lozzio
Keyword(s):  
Cell Line ◽  
Chronic Myelogenous Leukemia ◽  
Culture Media ◽  
Specific Antigen ◽  
Philadelphia Chromosome ◽  
Experimental Studies ◽  
Leukemia Cell ◽  
Myelogenous Leukemia ◽  
Chromosome 17 ◽  
Leukemia Cell Line

Abstract A cell-line derived from a patient with chronic myelogenous leukemia (CML) is described. The new cell-line, which has over 175 serial passanges in a 3 1/2-yr period, has the following characteristics: (1) CML cells started to proliferate actively since they were first incubated in culture media. A threefold increase in the total number of cells was observed during the first seven passages; the cell population increased by a factor of 10 to 20 every 7 days from passage 8 through 85; from 20 to 40 times from passage 86 through 150, and more than 40 times after 150 passages. (2) The majority of the nononucleated cells are undifferentiated blasts. (3) The karyotype of all the cells examined show the Philadelphia (Ph1) chromosome and a long acrocentric marker plus aneuploidy. The Giemsa-banding studies identified the Ph1 chromosome as a terminal deletion of the long arm of chromosome 22:del(22)(q12) and the long acrocentric marker as an unbalanced reciprocal translocation of one chromosome 17 and the long arm of one chromosome 15. (4) The CML cells do not produce immunoglobulins, are free of mycoplasma, Epstein-Barr virus, and herpes-like virus particles. (5) CML cells have no alkaline phosphatase and myeloperoxidase activities and did not engulf inert particles. (6) Cultured CML cells provide a constant source of a specific antigen. This CML cell-line represents a unique source of CML cells with meaningful indicators of malignancy for clinical and experimental studies.

scholarly journals Microscopy and Microanalysis of an Extreme Case of Salt and Biodegradation in 17th Century Wall Paintings

2015 ◽  
Vol 21 (3) ◽  
pp. 606-616 ◽  
Author(s):  
Milene Gil ◽  
Maria Rosário Martins ◽  
Maria Luisa Carvalho ◽  
Cátia Souto ◽  
Stephane Longelin ◽  
...  
Keyword(s):  
Culture Media ◽  
Extreme Case ◽  
Biological Assessment ◽  
Salt Weathering ◽  
Bacterial Strains ◽  
Isolation And Identification ◽  
Mineralogical Characterization ◽  
Fungal Isolation ◽  
X Ray ◽  
Standard Culture

AbstractThe present study characterizes the main deterioration mechanisms affecting the early 17th frescoes of Casa de Fresco, the only known example in Portugal of a semi-underground leisure room richly decorated with a balcony over a water well. Frescoes from the vault are at risk due to salt weathering and biodeterioration. The aim of the research was identification of the deterioration materials, determination of their origin, and their effect on the frescoes before future intervention. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was used to determine salt morphology and microanalysis. The mineralogical characterization was performed by X-ray powder diffraction, complemented with µ-Raman and µ-Fourier transform infrared spectroscopy. Biological assessment was evaluated with optical microscopy and SEM-EDS. Bacterial and fungal isolation and identification were performed using standard culture media and methods according to Bergey’s Manual of Systematic Bacteriology and from the Compendium of Soil Fungi. The results show that Ca and Ca-Mg carbonates from the paint renderings are the predominant salt species affecting the site. Bacterial strains from the genera Bacillus and Pseudomonas and fungal strains from the Cladosporium spp. and Penicillium spp. were isolated in the salt formations, within and between the mortar layers. Azurite, malachite, and smalt paint layers are the most affected by the weathering conditions.

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