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1.
Mikrobiyol Bul ; 57(3): 432-443, 2023 Jul.
Article in Turkish | MEDLINE | ID: mdl-37462306

ABSTRACT

The Malassezia yeast species colonize on the skin immediately after birth and could be found on the healthy skin flora for life. Although they are more frequently involved in the etiology of common skin infections in the community, particularly Malassezia furfur could cause life-threatening infections such as fungemia. Detection of biofilm during the colonization of these yeasts on the skin is an important criterion for its virulence. Since they are lipophilic yeasts, commonly used biofilm detection methods are not applicable to the Malassezia strains. The aim of the study was to describe the growth and measurement of M.furfur isolates on a polypropylene membrane to demonstrate their biofilm-forming capacities. Twenty-seven M.furfur strains colonized in the newborns were included in the study. Basically, sterile polypropylene membranes were placed on different polysorbates (tween 20, 40, and 80) which were spread on Sabouraud dextrose agar. Ten µl saline suspension of M.furfur was dropped on the polypropylene membrane and incubated in standard growth conditions for three days. Later, the visible colony was removed gently by washing with running water and the biofilm structure formed on the membrane was stained with safranin. The stained biofilm was photographed. Performing image analysis, the values obtained against background activity were digitized according to the specified protocol. Moreover, XTT reduction test was performed and the measured metabolic activity results were compared with the safranin-stained biofilm data. The safranin hydrolysis of the strains was measured spectrometrically. Twenty-five (92.6%) of the strains included in the study were stained with safranin, which indicated the presence of biofilm on the polypropylene membrane. The strains grown with tween 20 and tween 80 formed a higher biofilm layer density than those supplied with tween 40. Isolates with low and high biofilm-forming capacity were clearly separated by tween 20 (p< 0.05). XTT activity was detected in 26 (96.3%) isolates. No correlation was found between biofilm density obtained by the described method and XTT reduction. It was observed that hydrolysis of safranin did not affect the biofilm evaluation method. In this study, it was shown that as a result of sufficient diffusion through hydrophobic membranes, polysorbate-based growth factors could maintain measurement of the biofilm layer formed by lipophilic M.furfur strains. The best grouping properties for M.furfur were obtained with tween 20 which could determine low and high level of biofilm formation. Image analysis was used with high performance for this method. As conclusion, the utilization of different hydrophobic membranes and dyes would lead to the development of new techniques for the application in other lipophilic yeasts.


Subject(s)
Malassezia , Humans , Infant, Newborn , Polysorbates/metabolism , Polypropylenes/metabolism , Skin , Biofilms
2.
Jpn J Infect Dis ; 76(6): 335-342, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37394461

ABSTRACT

Myroides species have recently been reported more frequently in outbreaks in clinics and intensive care units (ICUs). In this study, we aimed to investigate the epidemic potential, antibiotic resistance profile, and risk factors of M. odoratimimus isolates that are increasingly being isolated from the ICUs of our hospital. Data from patients whose Myroides spp. were isolated from their clinical specimens over a 5-year period (September 2016 to January 2022) were retrospectively analyzed. Bacterial identification was performed using a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The presence of antibiotic resistance genes was analyzed using polymerase chain reaction (PCR). Possible clonal associations between isolates were investigated using enterobacterial repetitive intergenic consensus (ERIC)-PCR. As a result, 66 isolates were identified as M. odoratimimus and one isolate was identified as M. odoratus. The blaMUS resistance gene was detected in all M. odoratimimus isolates, whereas sul2 was detected in ten isolates and tetX was detected in 11 isolates. No other resistance genes, such as blaTUS, were detected. Additionally, two different clonal association patterns were discovered in the 24 selected isolates through the ERIC-PCR method. The increase in the immunosuppressive patient population indicate the possibility of encountering this agent and other opportunistic pathogens more frequently in the future.


Subject(s)
Enterobacteriaceae , Persistent Infection , Humans , Retrospective Studies , Drug Resistance, Multiple, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Disease Outbreaks , Hospitals , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
3.
Mikrobiyol Bul ; 56(2): 218-229, 2022 Apr.
Article in Turkish | MEDLINE | ID: mdl-35477226

ABSTRACT

Infections caused by multi drug-resistant gram-negative bacilli are increasingly reported worldwide. Colistin, tigecycline and aminoglycosides are almost the only and last choice antibiotics in the treatment of infections caused by carbapenem-resistant Enterobacterales members. Ceftazidime-avibactam is a novel antibiotic combination consisting of a broad-spectrum cephalosporin and avibactam with good antimicrobial activity against carbapenem-resistant Enterobacterales members. The aim of this study was to assess the in vitro activity of ceftazidime-avibactam and colistin against carbapenem-resistant Klebsiella pneumoniae isolates and to obtain local antimicrobial surveillance data. A total of 150 carbapenem-resistant K.pneumoniae isolates obtained from various clinical samples of the patients hospitalized in our hospital between 2018-2021 were included in the study. Duplicate isolates were excluded from the study. The isolates were recovered from blood (n= 72), tracheal aspirate (n= 40), wound (n= 20), biopsy and abscess (n= 10), steril body fluid (n= 5), and peripheral venous catheter (n= 3) samples. Isolates were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS, Bruker Daltonics, Germany). The minimum inhibitory concentration (MIC) values of the isolates for meropenem, colistin, ceftazidime, and ceftazidime-avibactam were determined by broth microdilution method. Susceptibility of the isolates to the tested antibiotics was evaluated by the European Committee of Antimicrobial Susceptibility Testing (EUCAST) criteria. The presence of carbapenemases (VIM, IMP, NDM, KPC, and OXA-48) was investigated by polymerase chain reaction (PCR) using specific primers. The mcr-1, mcr-2, mcr-3, mcr-4, and mcr-5 genes were evaluated by PCR for plasmid-mediated colistin resistance. All K.pneumoniae isolates were found to be positive for at least one of the carbapenemase genes evaluated in the study. The blaOXA-48 gene was detected in 107 (71.3%), blaKPC gene in 25 (16.7%); blaNDM gene in 7 (4.7%), co-production of blaOXA-48 and blaKPC genes in 10 (6.7%), co-production of blaOXA-48 and blaNDM genes in 1 (0.6%) isolate. None of the isolates harbored the blaVIM and blaIMP genes. None of the mcr genes screened in the study were detected among the isolates. The susceptibility of the isolates to ceftazidime-avibactam and colistin was 92.7% (139/150) and 48% (72/150), respectively. The MIC50 and MIC90 values for meropenem, ceftazidime, ceftazidime-avibactam, and colistin of the isolates were determined as 32/256, > 128/> 128, 1/8, and 4/16 µg/ml, respectively. Of the ceftazidimeavibactam resistant isolates, seven were positive for blaNDM, three for blaKPC, and one for both blaOXA-48 and blaNDM genes. High ceftazidime-avibactam MIC levels (> 128 µg/ml) were detected in metallo-betalactamase producing isolates. Consequently, our data suggested that ceftazidime-avibactam exhibited as a good alternative therapeutic choice for carbapenem-resistant K.pneumoniae isolates. It is noteworthy that high rate of colistin resistance was detected in K.pneumoniae isolates. Another notable finding of this study is the increase in K.pneumoniae isolates producing blaKPC for our country. To prevent the development of resistance which is observed even in last-choice therapeutic antibiotics, the principles of rational antibiotic use should be followed. The appropriate antimicrobial susceptibility testing should be routinely performed for surveillance of ceftazidime-avibactam and colistin.


Subject(s)
Ceftazidime , Klebsiella pneumoniae , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Azabicyclo Compounds , Carbapenems/pharmacology , Ceftazidime/pharmacology , Colistin/pharmacology , Drug Combinations , Humans , Meropenem
4.
Open Forum Infect Dis ; 9(4): ofac078, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35345665

ABSTRACT

Background: We evaluated the epidemiology of candidemia among coronavirus disease 2019 (COVID-19) patients admitted to intensive care units (ICUs). Methods: We conducted a retrospective multicenter study in Turkey between April and December 2020. Results: Twenty-eight of 148 enrolled patients developed candidemia, yielding an incidence of 19% and incidence rate of 14/1000 patient-days. The probability of acquiring candidemia at 10, 20, and 30 days of ICU admission was 6%, 26%, and 50%, respectively. More than 80% of patients received antibiotics, corticosteroid, and mechanical ventilation. Receipt of a carbapenem (odds ratio [OR] = 6.0, 95% confidence interval [CI] = 1.6-22.3, P = .008), central venous catheter (OR = 4.3, 95% CI = 1.3-14.2, P = .02), and bacteremia preceding candidemia (OR = 6.6, 95% CI = 2.1-20.1, P = .001) were independent risk factors for candidemia. The mortality rate did not differ between patients with and without candidemia. Age (OR = 1.05, 95% CI = 1.01-1.09, P = .02) and mechanical ventilation (OR = 61, 95% CI = 15.8-234.9, P < .0001) were independent risk factors for death. Candida albicans was the most prevalent species overall. In Izmir, Candida parapsilosis accounted for 50% (2 of 4) of candidemia. Both C parapsilosis isolates were fluconazole nonsusceptible, harbored Erg11-Y132F mutation, and were clonal based on whole-genome sequencing. The 2 infected patients resided in ICUs with ongoing outbreaks due to fluconazole-resistant C parapsilosis. Conclusions: Physicians should be aware of the elevated risk for candidemia among patients with COVID-19 who require ICU care. Prolonged ICU exposure and ICU practices rendered to COVID-19 patients are important contributing factors to candidemia. Emphasis should be placed on (1) heightened infection control in the ICU and (2) developing antibiotic stewardship strategies to reduce irrational antimicrobial therapy.

5.
Mikrobiyol Bul ; 55(4): 480-491, 2021 Oct.
Article in Turkish | MEDLINE | ID: mdl-34666650

ABSTRACT

Increasing resistance to first-line antibiotics used in the treatment of infections caused by Salmonella and Shigella species is emerging. Azithromycin presents a good alternative treatment option for Salmonella and Shigella infections. However, there are limited data regarding the susceptibility of azithromycin in Turkey. In this study, we aimed to evaluate the susceptibility of Salmonella and Shigella species to azithromycin, to determine and compare the minimum inhibitory concentration (MIC) values and disk diffusion zone diameters. In addition, susceptibility to meropenem and first-line antibiotic options in isolates was also investigated. A total of 170 Salmonella, 76 Shigella clinical isolates collected between 2014 and 2018 in our hospital were tested for their susceptibility to azithromycin, meropenem, ampicillin, pefloxacin, trimetoprim-sulfamethoxazole, ceftazidime, and cefotaxime. Isolates were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry. The isolates were confirmed and serotyped by the reference laboratory using the conventional slide agglutination method. Susceptibility of the isolates to azithromycin and other antibiotics was evaluated by Kirby-Bauer disk diffusion method. MIC values of azithromycin were determined by the reference broth microdilution method. Combined disk diffusion test was used for the detection of extended spectrum beta-lactamase (ESBL) production. Polymerase chain reaction was performed for macrolide and carbapenem resistance genes and the detected resistance genes were confirmed by sequencing. Of the 76 Shigella isolates tested, 64 (84.2%) were identified as Shigella sonnei, 10 (13.2%) as Shigella flexneri, one (1.3%) as Shigella boydii, and one (1.3%) as Shigella dysenteriae. Among the 170 Salmonella isolates, 131 (77%) were identified as Salmonella enteritidis, 11(6.5%) as Salmonella Typhimurium, 8 (4.7%) as Salmonella Kentucky, 5 (2.9%) as Salmonella Paratyphi B, 4 (2.4%) as Salmonella Infantis, 3 (1.8%) as Salmonella Cholerasuis, and 8 (4.7%) as other serovars (Salmonella Agona, Salmonella Dabou, Salmonella Gallinarum, Salmonella Hadar, Salmonella Muenchen, Salmonella Newport, Salmonella Paratyphi C, Salmonella Senftenberg), respectively. ESBL production was determined as 7.9% (6/76) in Shigella isolates and 2.9% (5/170) in Salmonella isolates. A carbapenem resistant S.Senftenberg isolate positive for the blaOXA-48 resistance gene was detected in our study. Meropenem MIC value of the isolate was detected as > 32 µg/ml with gradient diffusion test. Among all isolates, only one S.boydii isolate was detected as resistant to azithromycin with a MIC value of 128 µg/ml. The isolate was positive for the existence of mphA gene by PCR. In the disk diffusion test, azithromycin inhibition zone diameters were ≥ 12 mm in all of the tested isolates, except for the azithromycin-resistant isolate, and the azithromycin MICs were determined as ≤ 16 µg/ ml by broth microdilution. Increasing resistance to commonly used antibiotics in Salmonella and Shigella species is emerging. The detection of a carbapenem-resistant Salmonella isolate in our study indicates that the spread of carbapenem resistance to other Enterobacterales species may cause global problems. Antimicrobial susceptibility testing of azithromycin for Salmonella and Shigella species has been difficult to establish due to the lack of approval in vitro breakpoints for all species. Consequently, our data shows that azithromycin exhibits as a good alternative therapeutic choice for the treatment of gastrointestinal diseases caused by Salmonella and Shigella species. Further studies are needed to provide appropriate in vitro breakpoints supported by clinical data.


Subject(s)
Azithromycin , Shigella , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Azithromycin/pharmacology , Carbapenems/pharmacology , Drug Resistance, Bacterial/genetics , Humans , Microbial Sensitivity Tests , Salmonella/genetics , Shigella/genetics
6.
Mycopathologia ; 186(1): 41-51, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33392857

ABSTRACT

The arthroconidial yeasts Magnusiomyces capitatus and M. clavatus are emerging opportunistic pulmonary pathogens. They are closely related and difficult to distinguish based on morphological and physiological traits. We applied an SYBR® green-based quantitative PCR (qPCR) assay to identify the species. We analyzed 30 reference strains originating from clinical and environmental sources by targeting the Rpb2 gene encoding the second largest subunit of RNA polymerase II. The qPCR assays were tested by direct identification of M. capitatus and M. clavatus in spiked sputum and household dishwasher swabs, respectively, as models for clinical and environmental samples. The assays were proved to be reliable for species-level identification of both species, with 100% sensitivity and 100% specificity, lowest inter-assay deviations (RSDr ≤ 1.65%, R2 values >0.99), detection limit of 10 theoretical copy number of target DNA, and detection cell limit of ≥5000 yeast cells from spiked sputum samples. The developed qPCR assay is a practical molecular approach for the detection of M. capitatus and M. clavatus that can be used as a stand-alone assay or in conjunction with culture-dependent approaches.


Subject(s)
Saccharomycetales , Yeasts , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity
7.
Mycoses ; 59(6): 343-50, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26857806

ABSTRACT

The black yeast genus Exophiala is known to cause a wide variety of diseases in severely ill individuals but can also affect immunocompetent individuals. Virulence markers and other physiological parameters were tested in eight clinical and 218 environmental strains, with a specific focus on human-dominated habitats for the latter. Urease and catalase were consistently present in all samples; four strains expressed proteinase and three strains expressed DNase, whereas none of the strains showed phospholipase, haemolysis, or co-haemolysis activities. Biofilm formation was identified in 30 (13.8%) of the environmental isolates, particularly in strains from dishwashers, and was noted in only two (25%) of the clinical strains. These results indicate that virulence factors are inconsistently present in the investigated Exophiala species, suggesting opportunism rather than pathogenicity.


Subject(s)
Environmental Microbiology , Exophiala/pathogenicity , Opportunistic Infections/microbiology , Phaeohyphomycosis/microbiology , Virulence Factors/metabolism , Biofilms/growth & development , Catalase/metabolism , DNA, Fungal , DNA, Ribosomal Spacer , Deoxyribonucleases/genetics , Deoxyribonucleases/metabolism , Exophiala/metabolism , Exophiala/physiology , Humans , Peptide Hydrolases/genetics , Peptide Hydrolases/metabolism , Phospholipases/genetics , Phospholipases/metabolism , Phylogeny , Sequence Analysis, DNA , Urease/metabolism , Virulence
8.
Microb Ecol ; 71(2): 339-46, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26373644

ABSTRACT

The present study compared two chemical-based methods, namely, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, to understand the misidentification of Exophiala dermatitidis and Exophiala phaeomuriformis. The study utilized 44 E. dermatitidis and 26 E. phaeomuriformis strains, which were partially treated with strong acids and bases for further evaluation. MALDI-TOF MS and ATR-FTIR spectroscopy data of the two Exophiala species were compared. Data groupings were observed for the chromic acid- and nitric acid-treated species when the black yeast sources were categorized as creosoted-oak sleepers, concrete sleepers, or dishwasher isolates. The MALDI-TOF MS data for the metalloenzyme-containing regions were consistent with the ATR-FTIR spectroscopy data. These results indicated that environmental isolates might contain metals not found in human isolates and might interfere with chemical-based identification methods. Therefore, MALDI-TOF MS reference libraries should be created for clinical strains and should exclude petroleum-associated environmental isolates.


Subject(s)
Exophiala/chemistry , Mycological Typing Techniques/methods , Phaeohyphomycosis/microbiology , Spectroscopy, Fourier Transform Infrared/methods , Tandem Mass Spectrometry/methods , Exophiala/classification , Exophiala/isolation & purification , Humans , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
9.
Turk J Med Sci ; 45(3): 587-92, 2015.
Article in English | MEDLINE | ID: mdl-26281324

ABSTRACT

BACKGROUND/AIM: Mycological media that promote spore production are essential for the diagnosis of dermatophytosis. However, these culture media frequently become contaminated by multiple fungal or bacterial species during culture. The aim of this study was to compare the contamination rates of 6 culture media used for the isolation and identification of dermatophytes, including Borelli's lactritmel agar (BLA), brain-heart infusion agar (BHIA), Lowenstein-Jensen agar (LJA), malt extract agar (MEA), potato dextrose agar (PDA), and Sabouraud glucose agar (SGA). MATERIALS AND METHODS: Agar plates were inoculated with 43 well-characterized dermatophyte strains, belonging to the genera Arthroderma, Epidermophyton, Microsporum, or Trichophyton. The agar plates were incubated at 26 °C and examined every 5 days for 1 month. RESULTS: By the end of the incubation period, 97 of the 258 plates (37.6%) were contaminated by fungi. No bacteria were detected. Overall, BLA demonstrated the lowest rate of contamination, followed by SGA, MEA, BHIA, PDA, and LJA. Sequencing of the internal transcribed spacer region rDNA of the contaminant fungi revealed that Aspergillus and Penicillium species were the most common contaminants. CONCLUSION: These results suggest that nonenriched culture media types, such as BLA or SGA, reduced contamination during dermatophyte subculture.


Subject(s)
Agar/chemistry , Arthrodermataceae/classification , Arthrodermataceae/isolation & purification , Culture Media/chemistry , Equipment Contamination/statistics & numerical data , Spores, Fungal/growth & development , Mycological Typing Techniques
10.
Eur Arch Otorhinolaryngol ; 272(6): 1525-8, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25510984

ABSTRACT

The aim of this study was to investigate the effects of commonly used antibiotics on bacterial flora of the tonsil core. Patients who underwent tonsillectomy for recurrent chronic tonsillitis were included in the study. Three groups were formed: group 1 was treated for 10 days preoperatively with amoxicillin/clavulanic acid; group 2 was treated for 10 days preoperatively with clarithromycin; and group 3 included patients who underwent tonsillectomy without preoperative antibiotic use. The removed palatine tonsils were sent to our microbiology department in sterile tubes for bacteriological analysis. Seventy-three patients (group 1 = 19, group 2 = 20, group 3 = 34 patients) aged 3-18 years (mean 7 years) were included in the study. At least one bacterium was isolated from all tonsils, except for two cases in group 1; the difference in single bacterial growth among groups was not significant (p = 0.06). On the other hand, the numbers of patients with pathogenic bacterial growth was significantly lower in group 2 (n = 2) compared with group 1 (n = 10) and group 3 (n = 27) (p < 0.001). The bacterium isolated most frequently from the tonsils was Streptococcus viridans. Pseudomonas aeruginosa was the only pathogenic bacterium that grew in all three groups. Clarithromycin was more effective than amoxicillin/clavulanic acid in eradicating pathogenic bacteria in the tonsil core. Pseudomonas aeruginosa might be responsible for resistant or recurrent tonsil infections. To prevent endocarditis, antibiotic prophylaxis toward S. viridians, which is the most prevalent bacterium in the tonsil core, should be kept in mind for patients with heart valve damage.


Subject(s)
Amoxicillin-Potassium Clavulanate Combination/administration & dosage , Clarithromycin/administration & dosage , Palatine Tonsil , Pseudomonas aeruginosa , Tonsillitis , Viridans Streptococci , Anti-Bacterial Agents/administration & dosage , Bacteria/isolation & purification , Chemoprevention/methods , Chemoprevention/statistics & numerical data , Child , Chronic Disease , Female , Humans , Male , Palatine Tonsil/microbiology , Palatine Tonsil/pathology , Prevalence , Prospective Studies , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/isolation & purification , Recurrence , Tonsillectomy/methods , Tonsillitis/microbiology , Tonsillitis/physiopathology , Tonsillitis/surgery , Turkey , Viridans Streptococci/drug effects , Viridans Streptococci/isolation & purification
11.
Mycoses ; 58(1): 40-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25476038

ABSTRACT

Dermatophytes are some of the most common fungal pathogens in both humans and animals. These fungi release enzymes (e.g., keratinases) that play roles in their pathogenesis. Little is known about their haemolytic and co-haemolytic (CAMP-like) activities; however, in bacteria, these components play significant roles in pathogenesis. This study characterised these two factors in 45 dermatophyte strains (representing the genera Arthroderma, Epidermophyton, Microsporum and Trichophyton) using Columbia agar (CA) supplemented with 5% bovine, ovine and equine erythrocytes. Haemolysis was best observed on CA supplemented with ovine erythrocytes followed by equine and bovine erythrocytes, while CAMP-like reactions occurred using bovine and ovine but not equine erythrocytes. Haemolytic and CAMP-like activities were best observed using ovine and bovine erythrocytes in CA in 44 and 38 strains at 7 and 3 days respectively. Most dermatophytes recovered from both symptomatic and asymptomatic lesions had haemolytic and CAMP-like activities. We suggest that the haemolytic and CAMP-like activities are not correlated with ecological characteristics, isolation sites or clinical manifestations of dermatophytic fungi. We also believe that this study has the potential to contribute to the existing literature on dermatophytes and dermatophyte pathogenesis.


Subject(s)
Arthrodermataceae/metabolism , Arthrodermataceae/pathogenicity , Fungal Proteins/metabolism , Hemolysin Proteins/metabolism , Hemolysis , Animals , Arthrodermataceae/isolation & purification , Cattle , Epidermophyton/isolation & purification , Epidermophyton/metabolism , Epidermophyton/pathogenicity , Horses , Humans , Microsporum/isolation & purification , Microsporum/metabolism , Microsporum/pathogenicity , Sheep , Trichophyton/isolation & purification , Trichophyton/metabolism , Trichophyton/pathogenicity
12.
Microb Ecol ; 68(4): 699-707, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25027275

ABSTRACT

The environmental isolation of opportunistic pathogenic black yeasts, which are responsible for a wide spectrum of human infections, is essential to understanding the ecology of clinical fungi. Extreme outdoor environments polluted with aromatic hydrocarbons support the growth of black yeasts in unlikely places, such as railway sleepers. However, there are limited data concerning the diversity of these fungi growing on polluted railway sleepers. In this investigation, we examined 845 railway sleeper samples, obtained from 11 Turkish cities representing altitudes from 25 to 1,893 m, and inoculated the samples onto mycological media for the isolation of black yeasts. Ninety-four samples (11.1 %) yielded positive results for black yeast, with creosoted oak sleepers having a significantly higher number of isolates than concrete sleepers (p < 0.05). Identification based on the ribosomal DNA (rDNA) internal transcribed spacer region revealed the highest prevalence of Exophiala phaeomuriformis, followed by Exophiala dermatitidis, Exophiala heteromorpha, Exophiala xenobiotica, and Exophiala crusticola. This study revealed that railway sleepers harboring black yeasts were predominantly (>75 %) populated with thermophilic species. We observed that altitude might have a significant effect on species diversity. Briefly, E. phaeomuriformis exhibited growth over a wide altitude range, from 30 to 1,893 m. In contrast, E. dermatitidis had a remarkable aversion to low altitudes and exhibited maximum growth at 1,285 m. In conclusion, we speculate that one can predict what species will be found on railway sleepers and their probability and that species diversity primarily depends on sleeper type and altitude height. We believe that this study can contribute new insights into the ecology of black yeasts on railway sleepers and the railway factors that influence their diversity.


Subject(s)
Biodiversity , Climate , Exophiala/physiology , Railroads , Wood/microbiology , Altitude , Creosote/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Exophiala/genetics , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Turkey
13.
Diagn Microbiol Infect Dis ; 80(1): 43-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24953539

ABSTRACT

Human papillomavirus (HPV) DNA testing has become an important component of cervical cancer screening programs. In this study, we aimed to evaluate the efficiency of MY09/11 consensus polymerase chain reaction (PCR) for the detection of multiple HPV infections. For this purpose, MY09/11 PCR was compared to an original TaqMan-based type-specific real-time PCR assay, which can detect 20 different HPV types. Of the 654 samples, 34.1% (223/654) were HPV DNA positive according to at least one method. The relative sensitivities of MY09/11 PCR and type-specific PCR were 80.7% (180/223) and 97.8% (218/223), respectively. In all, 352 different HPV isolates (66 low-risk and 286 high-risk or probable high-risk types) were identified in 218 samples, but 5 samples, which were positive by consensus PCR only, could not be genotyped. The distribution of the 286 high-risk or probable high-risk HPVs were as follows: 24.5% HPV-16, 8.4% HPV-52, 7.7% HPV-51, 6.3% HPV-39, 6.3% HPV-82, 5.6% HPV-35, 5.6% HPV-58, 5.6% HPV-66, 5.2% HPV-18, 5.2% HPV-68, and 19.6% the other 8 types. A single HPV type was detected in 57.3% (125/218) of the genotyped samples, and multiple HPV types were found in the remaining 42.7% (93/218). The false-negative rates of MY09/11 PCR were found to be 17.4% in single infections, 23.3% in multiple infections, and 34.6% in multiple infections that contained 3 or more HPV types, with the condition that the low-risk types HPV-6 and HPV-11 be considered as a monotype. These data suggest that broad-range PCR assays may lead to significant data loss and that type-specific PCR assays can provide accurate and reliable results during cervical cancer screening.


Subject(s)
Human Papillomavirus DNA Tests/methods , Papillomaviridae/genetics , Papillomavirus Infections/diagnosis , Papillomavirus Infections/virology , Adolescent , Adult , Aged , Aged, 80 and over , Cervix Uteri/virology , Female , Humans , Middle Aged , Papillomaviridae/classification , Polymerase Chain Reaction , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Dysplasia/virology , Young Adult
14.
Int J Pediatr Otorhinolaryngol ; 78(8): 1288-93, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24882454

ABSTRACT

OBJECTIVE: In this study, we aimed to investigate the presence and copy number of six different viruses in tonsillar tissue samples removed surgically because of chronic recurrent tonsillitis or chronic obstructive tonsillar hypertrophy. METHODS: In total, 56 tissue samples (tonsillar core) collected from 44 children and 12 adults were included in this study. The presence of viruses was investigated using a new TaqMan-based quantitative real-time PCR assay. RESULTS: Of the 56 tissue samples, 67.9% (38/56) were positive for at least one of the six viruses. Epstein-Barr virus was the most frequently detected virus, being found in 53.6% (30/56), followed by human Parvovirus B19 21.4% (12/56), human adenovirus 12.5% (7/56), human Cytomegalovirus 5.4% (3/56), BK polyomavirus 1.8% (1/56), and Herpes simplex virus 1.8% (1/56). Precancerous or cancerous changes were not detected in the tonsillar tissue samples by pathologic examination, whereas lymphoid hyperplasia was observed in 24 patients. In contrast to other viruses, B19 virus was present in high copy number in tonsillar tissues. The rates of EBV and B19 virus with high copy number (>500.000 copies/ml) were higher in children than in adults, and a positive relationship was also found between the presence of EBV and the presence of B19 virus with high copy number (P=0.037). CONCLUSIONS: It is previously reported that some viral agents are associated with different chronic tonsillar pathologies. In the present study, the presence of B19 virus in tonsillar core samples was investigated quantitatively for the first time, and our data suggests that EBV infections could be associated with B19 virus infections or could facilitate B19 virus replication. However, further detailed studies are needed to clarify this observation.


Subject(s)
Herpesvirus 4, Human/isolation & purification , Palatine Tonsil/pathology , Palatine Tonsil/virology , Parvovirus B19, Human/isolation & purification , Tonsillitis/virology , Adenoviruses, Human/genetics , Adenoviruses, Human/isolation & purification , Adult , BK Virus/genetics , BK Virus/isolation & purification , Child , Child, Preschool , Chronic Disease , Cytomegalovirus/genetics , Cytomegalovirus/isolation & purification , DNA, Viral/isolation & purification , Female , Herpesvirus 4, Human/genetics , Humans , Hyperplasia , Hypertrophy , Infant , Lymphoid Tissue/pathology , Male , Parvovirus B19, Human/genetics , Real-Time Polymerase Chain Reaction , Tonsillectomy , Tonsillitis/surgery , Young Adult
15.
Mycopathologia ; 178(1-2): 111-5, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24925144

ABSTRACT

Mucormycosis is increasingly common in patients with risk factors such as diabetes mellitus, neutropenia, and corticosteroid therapy. However, mucormycosis seems to be less common in patients with human immunodeficiency virus (HIV) infection compared to patients with other risk factors. Despite their lower virulence, Lichtheimia species should be regarded as emerging pathogens among Mucoralean fungi. We report a fatal case of pulmonary mucormycosis due to Lichtheimia ramosa in a 52-year-old man with an end-stage HIV infection. He had a cachectic appearance and his CD4 count was 8 cells/mm(3). The fungal infection was diagnosed based on a positive sputum culture with histopathologic confirmation. The fungus was resistant to caspofungin, anidulafungin, and voriconazole [minimum inhibitory concentration (MCI) >32 µg/ml], whereas the E test MIC values of itraconazole, posaconazole, and amphotericin B were 0.38, 0.38, and 0.5 µg/ml, respectively. Although intravenous drug use is the main risk factor for the development of mucormycosis in HIV-infected patients, it may also develop in patients with low CD4 count, opportunistic infections and/or additional diseases, such as Kaposi's sarcoma or severe immunodeficiency, as in our case.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , AIDS-Related Opportunistic Infections/microbiology , Mucorales/isolation & purification , Mucormycosis/diagnosis , Mucormycosis/microbiology , AIDS-Related Opportunistic Infections/pathology , Antifungal Agents/pharmacology , CD4 Lymphocyte Count , Drug Resistance, Fungal , Fatal Outcome , Histocytochemistry , Humans , Immunocompromised Host , Male , Microbial Sensitivity Tests , Middle Aged , Mucorales/classification , Mucorales/drug effects , Mucormycosis/pathology , Sputum/microbiology
16.
J Microbiol Methods ; 97: 44-50, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24365111

ABSTRACT

In this study, we aimed to develop a cost-effective, practical, and sensitive method to be used for the diagnosis of HPV infections. The presence of HPV-DNA was investigated in cervical smear samples using three different methods: MY09/11 consensus PCR, TaqMan-based type-specific real-time PCR, and SYBR Green-based multiplex PCR. Of the 315 samples, 21.6% (68/315) were HPV-DNA positive by using at least one of the three methods. The relative sensitivities of MY09/11 PCR, type-specific PCR, and multiplex PCR were found to be 86.8% (59/68), 91.2% (62/68), and 91.2% (62/68), respectively. Genotyping analyses were successfully carried out in 62 of 68 HPV-DNA positive samples, and 77 isolates (8 low-risk and 69 high-risk HPV) were identified, while six samples were determined to be positive by consensus PCR only and could not be genotyped. The type distribution of the 69 high-risk HPV strains was as follows: 37.7% HPV 16, 13.0% HPV 52, 11.6% HPV 58, 7.2% HPV 18, 7.2% HPV 31, 7.2% HPV 68, 4.3% HPV 35, 4.3% HPV 39, 4.3% HPV 82, 1.4% HPV 33, and 1.4% HPV 45. Our data suggests that the diagnosis of HPV infections using only consensus PCR may lead to epidemiologically significant data loss, and that our multiplex PCR is more sensitive than consensus PCR and lower in cost than the type-specific PCR. We believe that the SYBR Green-based multiplex PCR may be useful and cost-effective for other microbiological fields. In addition, type-specific screening of HPV-DNA gives more reliable results, but it may also be used in combination with consensus PCR if the type spectrum of the test is not large enough.


Subject(s)
Human Papillomavirus DNA Tests/standards , Multiplex Polymerase Chain Reaction/standards , Papillomaviridae/genetics , Papillomavirus Infections/diagnosis , Real-Time Polymerase Chain Reaction/standards , Adolescent , Adult , Aged , DNA Primers/genetics , DNA, Viral/genetics , Female , Genotype , Humans , Middle Aged , Papillomavirus Infections/virology , Sensitivity and Specificity , Young Adult
17.
Mycopathologia ; 176(1-2): 23-31, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23591622

ABSTRACT

An in vitro hair perforation test is used to differentiate isolates of Trichophyton mentagrophytes and Trichophyton rubrum complexes because morphological criteria are insufficient. Here, we performed in vitro hair perforation tests using blond prepubertal hair and albino adult hair to determine whether they differentiate between fungal species. We tested 43 well-characterized dermatophyte strains, Arthroderma spp. [n = 4], Epidermophyton floccosum [n = 1], Microsporum spp. [n = 8], and Trichophyton spp. [n = 30], and examined hair perforation at 3-30 days postinoculation (p.i.). The perforation times were not significantly different between the two hair types (P > 0.05). The T. mentagrophytes complex strains perforated hair 4-5 days p.i., whereas T. rubrum complex strains perforated hair 13-30 days p.i., except for Trichophyton violaceum, which perforated hair after 6-7 days. Thus, the hair perforation test is highly sensitive (100 %) and specific (100 %) for differentiating T. mentagrophytes from T. rubrum complexes 5 days p.i. At 14 and 30 days, the sensitivity and negative predictive value of the test remained unchanged (100 %), but the specificity was reduced (64.3 and 14.3 %, respectively). Consistent with previous reports, we observed "perforating organs" of zoophilic Microsporum canis and geophilic Microsporum gypseum at 4 and 3 days, respectively. This paper offers a "low-cost" and "low-tech" alternative to differentiating dermatophyte species where standard morphological techniques fail and/or where molecular techniques are not a viable option.


Subject(s)
Arthrodermataceae/classification , Arthrodermataceae/growth & development , Hair/metabolism , Hair/microbiology , Mycology/methods , Arthrodermataceae/metabolism , Child, Preschool , Female , Humans , Male , Sensitivity and Specificity , Time Factors , Young Adult
18.
Mycoses ; 56(3): 250-5, 2013 May.
Article in English | MEDLINE | ID: mdl-23006021

ABSTRACT

We investigated the epidemiological characteristics of both symptomatic and asymptomatic dermatophytic groin infections in 1970 women (age: 36.2 ± 12.5) during routine gynaecologic examinations. Bilateral groin samples were collected with sterile cotton swabs premoistened with sterile physiological saline. The samples were then separately inoculated onto Sabouraud glucose agar. Fungi were identified by sequencing the rDNA internal transcribed spacer region. Dermatophytes were recovered from five patients (four Trichophyton rubrum and one Arthroderma vanbreuseghemii, 0.25%) with a diagnosis of asymptomatic carriers (four) and tinea inguinalis (one). In one case, groin carriage converted into tinea inguinalis after 3 weeks. Analysis of risk factors indicated that patients of at least 49 years were more likely to be positive for dermatophyte isolation (P = 0.002). In conclusion, groin dermatophyte carriage is more common than tinea inguinalis and can potentially convert into a symptomatic infection.


Subject(s)
Carrier State/diagnosis , DNA, Fungal/analysis , Groin/microbiology , Tinea/pathology , Trichophyton/isolation & purification , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Arthrodermataceae/isolation & purification , Carrier State/microbiology , Child , DNA, Ribosomal Spacer/analysis , Female , Groin/pathology , Humans , Middle Aged , Naphthalenes/therapeutic use , Risk Factors , Terbinafine , Tinea/drug therapy , Young Adult
19.
Mycoses ; 56(2): 95-100, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22621172

ABSTRACT

Participation in competitive sports is popular and widely encouraged worldwide. Herein, we investigated 252 male and 67 female sports players, aged 16.4 ± 1.3 years, active in 15 different types of combat (n = 143) and non-combat (n = 176) sports. Of the 319 participants in this study, 11 (3.5%) players, including six wrestlers, four football players and one handball player, all of whom were men, harboured dermatophytic fungi. Briefly, Trichophyton tonsurans was present in three athletes, who were scalp carriers of the fungus. Furthermore, T. rubrum (4), T. interdigitale (3) and Arthroderma simii (1) were recovered from eight participants with tinea inguinalis (4), tinea pedis (2) or both (1). One patient was a trunk carrier of concomitant tinea pedis. All dermatophytic fungi were identified using both direction sequence of the rDNA regions spanning the internal transcribed spacers (ITS1 and ITS2) and 5.8 rRNA gene. Although sports-active individuals are active and sweat more, we observed a low prevalence of dermatophytosis, both in combat (5.2%) and non-combat sports participants (3.4%) (P > 0.05). However, dermatophyte infections require more attention and appropriate management to eradicate the infection and to prevent possible outbreaks. This study also documents the first case of zoophilic A. simii in Turkey.


Subject(s)
Athletes , Tinea/epidemiology , Adolescent , Athletes/statistics & numerical data , Female , Humans , Male , Prevalence , Sports/classification , Sports/statistics & numerical data , Tinea/microbiology , Turkey/epidemiology , Young Adult
20.
Mikrobiyol Bul ; 46(4): 624-36, 2012 Oct.
Article in Turkish | MEDLINE | ID: mdl-23188576

ABSTRACT

Cervical cancer that has been proven to be associated with human papillomavirus (HPV) is the second most common cancer in women worldwide and is a leading cause of cancer deaths in women in developing countries. Cervical cancers can be detected in the early stages by screening programs since a long latency period exists between the beginning of HPV infection and the development of cervical cancer. HPV-DNA testing is widely used throughout the world and today is an important part of cervical cancer screening programs. In this study, we analyzed the presence of HPV-DNA in 356 cervical smear samples by two different methods which are MY09/11 consensus real-time polymerase chain reaction (Rt-PCR) and type-specific Rt-PCR. All samples were also tested by type-specific PCR, regardless of consensus PCR results. PCR analysis were performed using the type- specific primers and TaqMan probes that were designed for a total of 13 different HPV types; two low risk HPV and 11 high risk HPV types. A total of 142 different isolates, 95 being high risk HPV isolates, 39 low risk HPV isolates and eight unidentified isolates, were determined in 109 (30.6%) smear samples that were defined as HPV-DNA positive by at least one of the two methods. Frequencies of detection of high risk HPV types in HPV-positive samples were as follows respectively: HPV-16; 32 (33.7%), HPV-52; 12 (12.6%), HPV-58; 11 (11.6%), HPV-18; 7 (7.4%), HPV-31; 7 (7.4%), HPV-35; 7 (7.4%), HPV-68; 6 (6.3%), HPV-33; 4 (4.2%), HPV-82; 4 (4.2%), HPV-39; 3 (3.2%) and HPV-45; 2 (2.1%). Various cytologic atypia were reported in 84 (23.6%) smear samples according to the simultaneously performed cytopathologic examination. Single HPV type was detected in 72 (71.3%) and multiple HPV types were detected in 29 (28.7%) of 101 smear samples with the exception of the unidentified isolates by type-specific RtPCR. HPV-18, HPV-33 and HPV-35 had higher detection rates of 7.4, 3.7 and 3.0 fold in mixed infections than single ones, respectively. HPV-DNA could not be detected by MY09/11 consensus primers in 24 (23.8%) of 101 cervical smear samples that were accepted as HPV-DNA positive by type-specific PCR. Thus, investigation of the presence of HPV-DNA by only consensus primers would be insufficient for the diagnosis, treatment and follow-up of HPV infections. Initial assessment of smear samples by using consensus primers and genotyping only positive samples seem to be the most practical strategy for the diagnosis and screening of HPV infections throughout the world. When this situation is taken into consideration, we think that the current prevalence data in our country and around the world must be updated by using large-scale studies that apply new generation screening and diagnostic tests.


Subject(s)
Alphapapillomavirus/isolation & purification , Cervix Uteri/virology , Human Papillomavirus DNA Tests/methods , Papillomavirus Infections/diagnosis , Real-Time Polymerase Chain Reaction/methods , Uterine Cervical Neoplasms/diagnosis , Adolescent , Adult , Alphapapillomavirus/genetics , DNA Primers/chemistry , DNA, Viral/chemistry , DNA, Viral/isolation & purification , Female , Humans , Mass Screening , Middle Aged , Papillomavirus Infections/complications , Papillomavirus Infections/virology , Real-Time Polymerase Chain Reaction/standards , Uterine Cervical Neoplasms/prevention & control , Uterine Cervical Neoplasms/virology , Vaginal Smears , Young Adult
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