Fundamental niche prediction of the pathogenic yeasts cryptococcus neoformans and cryptococcus gattii in europe

Fundamental niche prediction of Cryptococcus neoformans and Cryptococcus gattii in Europe is an important tool to understand where these pathogenic yeasts have a high probability to survive in the environment and therefore to identify the areas with high risk of infection. In this study, occurrence data for C. neoformans and C. gattii were compared by MaxEnt software with several bioclimatic conditions as well as with soil characteristics and land use. The results showed that C. gattii distribution can be predicted with high probability along the Mediterranean coast. The analysis of variables showed that its distribution is limited by low temperatures during the coldest season, and by heavy precipitations in the driest season. C. neoformans var. grubii is able to colonize the same areas of C. gattii but is more tolerant to cold winter temperatures and summer precipitations. In contrast, the C. neoformans var. neoformans map was completely different. The best conditions for its survival were displayed in sub-continental areas and not along the Mediterranean coasts. In conclusion, we produced for the first time detailed prediction maps of the species and varieties of the C. neoformans and C. gattii species complex in Europe andMediterranean area

Kriptokokkoz için risk faktörü olarak Alanya şehir merkezinde Cryptococcus neoformans kolonizasyonunun ilk izolasyonu

Amaç: Bağışıklığı baskılanmış insanlarda ve hayvanlarda yaşamı tehdit eden enfeksiyonlara neden olabilen Cryptococcus neoformans ve Cryptococcus gattii, çevresel odaklardan hassas olan konağa bulaşır. Patojen biyoklimatik değişkenlere uygun şekilde çevresel kolonizasyon gösterir. Daha önceki MaxEnt makine öğrenmesi ile yapılan analizlerde, Alanya bölgesi muhtemel kolonizasyon bölgesi olarak saptanmıştır. Bu çalışmanın amacı, ülkemiz için önemli bir turizm bölgesi olan Alanya ve yakın çevresindeki kovuklu ağaç florasında C. neoformans ve C. gattii kolonizasyonunun araştırılmasıdır.Gereç ve yöntem: Alanya şehir merkezi ve yakınındaki Dim çayı çevresinden, üzerinde geniş kovuk olduğu belirlenen 49 zeytin (Olea europea), 17 keçiboynuzu (Ceratonia siliqua) ve 13 okaliptüs (Eucalyptus camaldulensis) olmak üzere toplam 79 ağaçtan standart eküvyon yöntemi ile örnekleme yapıldı. Bifenil ve kloramfenikol içeren Staib agar kültür için kullanıldı. Üreyen maya benzeri, kahverengi pigmentli koloniler konvansiyonel yöntemler ve kanavanin-glisin-bromtimol agar reaksiyonu ile tanımlandı. Bulgular: Alanya şehir merkezinde sadece bir (%2,04) zeytin (O. europea) ağacında C. neoformans kolonizasyonu saptandı. Sonuç: Bu çalışmada, C. neoformans'ın Türkiye'nin önemli turizm kenti olan Alanya şehir merkezinden izole ettiği ilk çevresel kolonizasyonu rapor edilmiştir. Çevresel insan patojenik mantarlarının kolonizasyonu için ülkemizin insan yerleşimlerinin ve turizm potansiyeli yüksek bölgelerinin sistematik olarak taranması riskli alanların bulunmasına yardımcı olacaktır

Prediction of the Species Distribution of Cryptococcus neoformans Throughout Turkey

WOS: 000465377600011PubMed ID: 31130127Cryptococcus neoformans is a human pathogenic yeast that causes life-threatening infections especially in immunosuppressed patients. The environmental isolation of C.neoformans from Turkey was reported as early as 2004, although this was mostly from Eucalyptus camaldulensis colonization. Successful isolations were also reported from pomegranate (Punica granatum), oriental plane (Platanus orientalis), pine tree (Pinaceae), chestnut (Castanea sativa) and salt cedar (Tamarix hispida). The investigation of the relationship between the bioclimatic factors affecting the environmental isolation sites and the colonization of pathogens is a frequently used method. With this method, detailed risk maps can be generated in which environmental colonization can be estimated. The aim of this study was to use the high-resolution bioclimatic and previously-isolated yeasts' coordinates to create a valid model for the occurrence of C.neoformans in Turkey and provide insight into ecological processes. A machine learning approach using presence-only data software, maximum entropy (MaxEnt), was used to for the prediction of C.neoformans distribution. Climatic data and environmental bioclimatic variables from WorldClim were downloaded as 30 seconds spatial resolutions. The correlation between different Turkey bioclimatic layers were analyzed with ENMTools and similar layers were discarded. Forty-one different coordinates representing C.neoformans isolation points were used to generate a predictive map. The area under the curve and the omission rate were used to validate the model. Meanwhile, Jackknife tests were applied to enumerate the contribution of different environmental variables, and then to predict the final model. Maps were created using QGIS mapping software. In this study, we have shown that the coastal region of Anatolia, which is geographically located in the Northeastern Mediterranean Basin, as well as the entire Aegean region, carry an extremely high risk for the colonization of C.neoformans. Other areas which have not previously been reported for the isolation of C.neoformans were predicted to be potential colonization hotspots, including the western part of Ataturk Dam, the Amik Plain and the Bakircay and Gediz valleys. The maximum temperature of the warmest month, the mean temperature of the warmest quarter and the precipitation of the coldest quarter were the most important factors influencing the model's predictions. It was determined that the humidity in the environment affected the colonization especially in November. In conclusion, we produced a C.neoformans colonization risk map of Turkey for the first time. Obtaining more regional data will facilitate the identification of the regions having similar risk. This approach is useful for the clinical prediagnosis of cryptococcosis cases, which may be more common in places with environmental niches

Flow Cytometry Optimization of Three Different BODIPY Molecules for Staining Lipid Droplets of Cryptococcus neoformans

The pathogenic Cryptococcus neoformans causes life-threatening disease in immunocompromised patients. Although there are hypotheses about the role of lipid droplets in C.neoformans pathogenesis, there is still not extensively data determined on the subject yet. Lipid droplets are dynamic cytoplasmic energy storage bodies in yeasts. Diazo dyes, Nile red, LD 540 and borradiazaindasen (BODIPY) molecules are frequently used in the lipid droplets studies. BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) dyestuffs are among the brightest green light emitting fluorophores. These neutral molecules have high lipophilicity and can easily pass through the cell wall and membrane. In this study, for the future studies on lipid droplets of C.neoformans, we aimed to optimize three different BODIPY (BODIPY480/525, BODIPY480/530, BODIPY480/535) molecules for fluorescence microscopy and flow cytometry system. Ten molecularly confirmed environmental C.neoformans strains were grown on Sabouraud dextrose agar with and without oleic acid. BODIPY staining protocols at different concentrations were used for C.neoformans lipid droplets fixed with paraformaldehyde. The visualization (by fluorescence microscopy) and detection (by flow cytometer) of the lipid droplet structures of C.neoformans strains were evaluated. Forwardscatter and side-scatter analysis were performed to evaluate the number of lipid droplets determined in the cytoplasmic region quadrant in flow cytometry. The staining of the lipid droplets of C.neoformans of all three BODIPY molecules used in the study was observed by fluorescence microscope with creating distinct brightness and sharp contrast with the background. All BODIPY molecules could be examined by fluorescence microscopy without loss of brightness in more than one minute. The optimal dye concentration of BODIPY compounds were found as 2 mu M. Incubation at room temperature for five minutes was sufficient for fluorochrome staining. They were also shown to be able to stain lipid droplets in heatinactivated C.neoformans strains in all three compounds. The synthesized BODIPY480/525, BODIPY480/53 and BODIPY480/535 molecules were evaluated in accordance with the staining of lipid droplets, which were claimed to play a role in the pathogenesis of C.neoformans, and analysis by fluorescence microscopy and analysis with flow cytometer. BODIPY molecules may exhibit different properties in staining lipid droplets. These molecules should be tested for demonstrating the presence of lipid droplets in different yeast species and their suitability for pathogenesis studies

An outbreak of tularemia in southwestern Turkey

Introduction: Tularemia has reemerged and spread throughout Turkey, and the number of cases has increased. In this study, we report on a waterborne outbreak of tularemia in the spring of 2013 in a region which was previously disease-free, and we investigated the reasons for the outbreak. Methodology: The index case, a 17-year-old male, was diagnosed with oropharyngeal tularemia. An outbreak investigation was initiated after receiving information from other patients with similar symptoms from the same village along with Balkica, Tavas, and Denizli. An epidemiological and environmental investigation was conducted. Tonsil swab specimens/lymph node aspirates collected from patients, and water samples collected from unchlorinated drinking water sources, were cultured. Additionally, a real-time polymerase chain reaction (RTPCR) was performed on these samples. Serum samples from patients were analyzed for antibody response. Results: A total of 7 patients were found in this outbreak investigation. The attack rate was found to be 1% among the people of the village and 25% among patients' family members. The drinking-water system was contaminated with F. tularensis during this outbreak. Conclusions: Lack of appropriate water infrastructure and sanitation was the primary reason for this tularemia outbreak in Turkey. Improving the water source infrastructure and sanitation should be the primary approach to preventing tularemia outbreaks

Exploiting processor features to implement error detection in reduced precision matrix multiplications

Modern processors incorporate complex arithmetic units that can work with large word-lengths. Those units are useful for applications that require high precision. There are however, many applications for which the use of reduced precision is sufficient. In those cases, one possibility is to use the large word-length arithmetic units to implement reduced precision operations with additional error detection. In this paper, this idea is explored for the case of matrix multiplications. A technique is presented and evaluated. The results show that it can detect most errors and that for large matrixes the overhead in terms of execution time is small. (C) 2014 Elsevier B.V. All rights reserved

Isolation of Cryptococcus neoformans from a chestnut tree (Castanea sativa), Denizli, Turkey

WOS: 000434852700767

Frequency of azole resistance in clinical and environmental strains of Aspergillus fumigatus in Turkey: a multicentre study

Objectives Aspergillus fumigatus causes several diseases in humans and azole resistance in A. fumigatus strains is an important issue. The aim of this multicentre epidemiological study was to investigate the prevalence of azole resistance in clinical and environmental A. fumigatus isolates in Turkey. Methods Twenty-one centres participated in this study from 1 May 2018 to 1 October 2019. One participant from each centre was asked to collect environmental and clinical A. fumigatus isolates. Azole resistance was screened for using EUCAST agar screening methodology (EUCAST E.DEF 10.1) and was confirmed by the EUCAST E.DEF 9.3 reference microdilution method. Isolates with a phenotypic resistance pattern were sequenced for the cyp51A gene and microsatellite genotyping was used to determine the genetic relationships between the resistant strains. Results In total, resistance was found in 1.3% of the strains that were isolated from environmental samples and 3.3% of the strains that were isolated from clinical samples. Mutations in the cyp51A gene were detected in 9 (47.4%) of the 19 azole-resistant isolates, all of which were found to be TR34/L98H mutations. Microsatellite genotyping clearly differentiated the strains with the TR34/L98H mutation in the cyp51A gene from the strains with no mutation in this gene. Conclusions The rate of observed azole resistance of A. fumigatus isolates was low in this study, but the fact that more than half of the examined strains had the wild-type cyp51A gene supports the idea that other mechanisms of resistance are gradually increasing.This work was partly supported by Bursa Uludag University Scientific Research Projects Commission (QUAP[T]-2015-5) and Ener Private Health Service Company.Bursa Uludag University Scientific Research Projects Commission [QUAP[T]-2015-5]; Ener Private Health Service Compan

Isolation of Cryptococcus neoformans from a Chesnut Tree (Castanea sativa), Denizli, Turkey

WOS: 000459548000007PubMed ID: 30683040Cryptococcus neoformans is a basidiomycetous encapsulated yeast that can cause life-threatening infections in immunosuppressed humans and animals. C. neoformans/Cryptococcus gattii infections are considered to be acquired via inhalation of aerosolized particles from the environment. Avian guano, decaying tree hollows and soil are known as environmental niches. In recent years, colonization of the woody structures of different trees such as Eucalyptus camaldulensis, Tamarix hispida, Platanus orientalis and Punica granatum has been reported in the environmental study of the western Anatolian region. Based on the results of previous studies, our country may have intensive Cryptococcus colonization niches in the western regions. The aim of this study was to investigate the presence of the colonization of C.neoformans niche in chestnut (Castanea spp.) trees on higher altitudes.. In the study, the colonization of C.neoformans was screened on chestnut trees (Castanea spp.) in Aydin-Odemis-Denizli geographical area. This area consists of mountainous terrain between the fertile plain formed by two major rivers.This region is one of the widespreading areas of chestnut farming in Anatolia. Two hundred and fourteen chestnut trees that had deep fissures or trunk hollows were screened during mid-summer 2017. A swabbing technique was used, and all samples were cultured on Staib agar medium containing biphenyl and antibiotics. Cultures were checked for ten days for suspicious brown colonies. Suspicious yeast colonies were tested for the identification of pathogenic Cryptococcus by conventional methods and canavanine-glycine-bromothymol agar reactions. ITS 1-4 primers were used for strain PCR tests. We determined the mating type and serotypes by PCR analysis of the STE20 genes using STE20 (Aa), STE20 (A alpha), STE20 (Da), and STE20 (D alpha) primers. V8 agar medium was used for mating cultivation. Only one (0.47%) strain of C. neoformans was isolated from 214 screened trees. This strain was confirmed by ITS 1-4 sequencing. The serotype A MAT alpha mating type was observed. Basidium, basidiospores and clamp connections in hyphal structure were noted with MAT alpha mating on V8 agar medium. In this study, the first C.neoformans isolate from a chestnut tree (Castanea sativa) was determined from Denizli region. Further studies of distribution of human pathogenic Cryptococcus will be helpful to determine the risk areas for the living organisms in our region