scholarly journals Molecular Epidemiology of Invasive Listeriosis due toListeria monocytogenesin a Spanish Hospital over a Nine-Year Study Period, 2006–2014

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Jaime Ariza-Miguel ◽  
María Isabel Fernández-Natal ◽  
Francisco Soriano ◽  
Marta Hernández ◽  
Beatrix Stessl ◽  
...  
Keyword(s):  
Genetic Relatedness ◽  
Growth Patterns ◽  
Phenotypic Characteristics ◽  
Genetic Studies ◽  
Epidemiological Analysis ◽  
Spanish Hospital ◽  
Northwestern Spain ◽  
High Degree ◽  
Sequence Types ◽  
Invasion Assays

We investigated the pathogenicity, invasiveness, and genetic relatedness of 17 clinicalListeria monocytogenesstains isolated over a period of nine years (2006–2014). All isolates were phenotypically characterised and growth patterns were determined. The antimicrobial susceptibility ofL. monocytogenesisolates was determined in E-tests. Invasion assays were performed with epithelial HeLa cells. Finally,L. monocytogenesisolates were subtyped by PFGE and MLST. All isolates had similar phenotypic characteristics (β-haemolysis and lecithinase activity), and three types of growth curve were observed. Bacterial recovery rates after invasion assays ranged from 0.09% to 7.26% (1.62 ± 0.46). MLST identified 11 sequence types (STs), and 14 PFGE profiles were obtained, indicating a high degree of genetic diversity. Genetic studies unequivocally revealed the occurrence of one outbreak of listeriosis in humans that had not previously been reported. This outbreak occurred in October 2009 and affected three patients from neighbouring towns. In conclusion, the molecular epidemiological analysis clearly revealed a cluster (three human cases, all ST1) of not previously reported listeriosis cases in northwestern Spain. Our findings indicate that molecular subtyping, in combination with epidemiological case analysis, is essential and should be implemented in routine diagnosis, to improve the tracing of the sources of outbreaks.

scholarly journals Molecular Diversity and Genetic Relatedness of Candida albicans Isolates from Birds in Hungary

2021 ◽  
Vol 186 (2) ◽  
pp. 237-244
Author(s):  
M. Domán ◽  
L. Makrai ◽  
Gy. Lengyel ◽  
R. Kovács ◽  
L. Majoros ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Molecular Diversity ◽  
Genetic Relatedness ◽  
Group Method ◽  
Pair Group ◽  
Degree Of Separation ◽  
Avian Origin ◽  
Species Specific ◽  
Sequence Types ◽  
Unweighted Pair Group Method

AbstractThe molecular epidemiology of Candida albicans infections in animals has been rarely studied. In this study, multilocus sequence typing was used to characterise the genetic diversity and population structure of 24 avian origin C. albicans isolates collected from different birds with candidiasis and compared to human isolates. Fourteen diploid sequence types (DSTs) including six new DSTs were determined. Cluster analysis revealed that isolates grouped into 8 clades. Bird isolates mainly belonged to minor clades and Clade 15 with DST 172 was the most common (11 isolates; 45.8%). The remaining isolates were clustered into Clade 7 (5 isolates; 20.8%), Clade 10 (4 isolates; 16.6%), Clade 8 (2 isolates; 8.3%), Clade 4 (1 isolate; 4.2%) and Clade 16 (1 isolate; 4.2%). Unweighted pair group method with arithmetic averages (UPGMA) and eBURST analyses showed that the genetic construction of avian origin C. albicans population is fairly diverse. Although species-specific lineages were not found, some degree of separation in the evolution of bird and human strains could be observed.

scholarly journals Evaluation of Two Supplemented Culture Media for Long-Term, Room-Temperature Preservation ofStreptococcus pneumoniaeStrains

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Beatriz Quintero Moreno ◽  
María Araque ◽  
Evelyn Mendoza
Keyword(s):  
Survival Time ◽  
Room Temperature ◽  
Culture Media ◽  
Skim Milk ◽  
Extended Period ◽  
Phenotypic Characteristics ◽  
Genetic Profiles ◽  
Sequence Types ◽  
Over Time

Objective. To produce two supplemented agar types in order to store pneumococci for several months at room temperature.Methods. Todd-Hewitt/Hemoglobin/Yeast/Charcoal/Agar (TH-HYC) and Todd-Hewitt/Skim-Milk/Yeast/Charcoal/Agar (TH-SYC) were used to prepare two supplemented agar types. Nineteen pneumococci isolated from patients or asymptomatic carriers displaying diverse serotypes and multilocus sequence types (MLST) were subcultured and stored onto supplemented agar types, in four different tests, at room temperature.Findings. At the end of all tests (4–6 months) all noncontaminated subcultures were viable and maintained all phenotypic characteristics. Survival-time curves revealed a slow decrease of viable CFU over time on agar types, but at the end the number of viable CFU was satisfactory (≥2+ of growth). Decreasing of CFU was significantly higher for clinical versus nasopharyngeal isolates. Subcultures contamination rates were 6.25% and 14.58% after 2 and 6 months of storage, respectively.Conclusion. TH-HYC and TH-SYC agar types allowed the viability of pneumococci with several serotypes, MLST, and genetic profiles, after 6 months of storage at room temperature. We consider that these agar types are a valid alternative to preserve pneumococci over an extended period, especially when methods as cryopreservation or lyophilization are not available, and are useful for transporting strains between laboratories.

scholarly journals Quantifying the prevalence of assortative mating in a human population

2019 ◽  
Author(s):  
Klaus Jaffe
Keyword(s):  
Assortative Mating ◽  
Genetic Relatedness ◽  
Random Mating ◽  
Human Populations ◽  
Genetic Composition ◽  
Genetic Studies ◽  
Maintenance Of Sex ◽  
Animal Populations ◽  
The Uk ◽  
First Time

AbstractFor the first time, empirical evidence allowed to construct the frequency distribution of a genetic relatedness index between the parents of about half a million individuals living in the UK. The results suggest that over 30% of the population is the product of parents mating assortatively. The rest is probably the offspring of parents matching the genetic composition of their partners randomly. High degrees of genetic relatedness between parents, i.e. extreme inbreeding, was rare. This result shows that assortative mating is likely to be highly prevalent in human populations. Thus, assuming only random mating among humans, as widely done in ecology and population genetic studies, is not an appropriate approximation to reality. The existence of assortative mating has to be accounted for. The results suggest the conclusion that both, assortative and random mating, are evolutionary stable strategies. This improved insight allows to better understand complex evolutionary phenomena, such as the emergence and maintenance of sex, the speed of adaptation, runaway adaptation, maintenance of cooperation, and many others in human and animal populations.

scholarly journals Molecular characterization of Anaplasma phagocytophilum infection in the cervids and feeding ticks from Lithuania

Biologija ◽  
2020 ◽  
Vol 66 (3) ◽  
Author(s):  
Jana Radzijevskaja ◽  
Justina Snegiriovaitė ◽  
Artūras Kibiša ◽  
Irma Ražanskė ◽  
Algimantas Paulauskas
Keyword(s):  
Sequence Analysis ◽  
Anaplasma Phagocytophilum ◽  
Red Deer ◽  
Roe Deer ◽  
Bacterial Pathogen ◽  
Epidemiological Studies ◽  
Msp4 Gene ◽  
Ixodes Ticks ◽  
High Degree ◽  
Sequence Types

Anaplasma phagocytophilum is a bacterial pathogen, which is a major cause of zoonotic disease, anaplasmosis. The main vectors of A. phagocytophilum are ticks of the Ixodes ricinus complex. A. phagocytophilum has a broad geographic distribution and a high degree of biological and clinical diversity. Epidemiological studies in multiple countries have shown that the prevalence of A. phagocytophilum highly depends on the density of ticks and their potential hosts such as the cervids, which are one of the main sources of nutrition for Ixodes ticks. In Lithuania, the cervids are important game animals but their contribution as reservoirs for A. phagocytophilum remains unknown. The objectives of the study were to investigate the prevalence of A. phagocytophilum infections in the cervids and feeding ticks and to characterize the A. phagocytophilum strains obtained from the cervids and ticks based on sequence analysis of msp4 gene. A total of 187 ticks were collected from 44 cervids (roe deer, red deer, and moose) harvested by professional hunters during the hunting seasons of 2010–2013 and 2016–2017 in Lithuania. Blood and spleen samples were collected from 29 animals (27 roe deer and two red deer). A. phagocytophilum DNA was identified in ten (37.04%) of the 27 roe deer. The overall prevalence of A. phagocytophilum in I. ricinus and D. reticulatus ticks was 39.3% (70/178) and 22.2% (2/9) respectively. The sequence analysis of the msp4 gene of A. phagocytophilum revealed nine different sequence types: five msp4 sequence types were detected in ticks and seven in roe deer.

scholarly journals Multiple sequence types responsible for healthcare-associated Acinetobacter baumannii dissemination in a single centre in Egypt

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Leena Al-Hassan ◽  
Mai M. Zafer ◽  
Hadir El-Mahallawy
Keyword(s):  
Acinetobacter Baumannii ◽  
Migratory Birds ◽  
Significant Risk ◽  
Carbapenem Resistance ◽  
Healthcare Setting ◽  
Multiple Sequence ◽  
Appropriate Treatment ◽  
Healthcare Associated ◽  
High Degree ◽  
Sequence Types

Abstract Background Acinetobacter baumannii is an increasingly worrying organism in the healthcare setting, due to its multidrug resistance and persistence. Prolonged hospitalisation, immunocompromised patients and excessive antibiotic exposure all contribute to increasing the risk of A. baumannii infections, which makes cancer patients a significant risk group. This study aims to investigate the dissemination of A. baumannii at the National Cancer Institute (NCI) in Cairo – Egypt. Methods All bacterial isolates were typed using Multi-locus Sequence Typing (MLST) to characterise the epidemiology of isolates. The intrinsic OXA-51-like, and the acquired carbapanemases OXA-23, − 24/40, − 58, NDM, IMP, and VIM were also amplified and sequenced to genetically identify mechanisms of carbapenem resistance. Results MLST results show a high degree of multi-clonal dissemination, with 18 different Sequence Types (STs) identified, including 5 novel. The majority of isolates belonged to International Clone (IC) 2, and carbapenem resistance was detected in 93% of isolates and mediated by blaOXA-23, blaOXA-58, blaNDM-1 and blaVIM-1. We also report the presence of a resistant ST732 (OXA-378) which has been previously identified in migratory birds. Conclusions Multiple highly resistant clones were identified in a Cancer hospital in Cairo. It is vital that clinicians and healthcare workers are aware of the population of A. baumannii present in order to have appropriate treatment and infection control practices.

Coreoleuciscus aeruginos (Teleostei: Cypriniformes: Cyprinidae), a new species from the Seomjin and Nakdong rivers, Korea

Zootaxa ◽  
2015 ◽  
Vol 3931 (1) ◽  
pp. 140 ◽  
Author(s):  
HA-YOON SONG ◽  
IN-CHUL BANG
Keyword(s):  
New Species ◽  
South Korea ◽  
Supporting Evidence ◽  
The South ◽  
Genetic Studies ◽  
Body Coloration ◽  
Morphological Differences ◽  
High Degree ◽  
A New Species ◽  
I Gene

Coreoleuciscus splendidus was first reported as a monotypic species. Recent morphological and genetic studies have revealed that the species is represented by two disjunct and distinct lineages. The two lineages of C. splendidus include populations inhabiting the Han and Geum rivers in the East Korea Subdistrict and populations inhabiting the Seomjin and Nakdong rivers in the South Korea Subdistrict. In this study, significant differences were found between these two independent lineages through a high degree of genetic divergence in the mitochondrial cytochrome c oxidase subunit I gene as well as conspicuous morphological differences in body coloration and shapes of black stripes on dorsal, anal and caudal fin rays. These morphological and genetic differences provide supporting evidence that the populations in the South Korea Subdistrict represent a new species, Coreoleuciscus aeruginos. 

scholarly journals Cross reactivity of neutralizing antibodies to the encephalitic California Serogroup orthobunyaviruses varies by virus and genetic relatedness

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alyssa B. Evans ◽  
Karin E. Peterson
Keyword(s):  
Gold Standard ◽  
Neutralizing Antibodies ◽  
Viral Encephalitis ◽  
Genetic Relatedness ◽  
Cross Reactivity ◽  
Etiologic Agent ◽  
Snowshoe Hare ◽  
Neuroinvasive Disease ◽  
California Serogroup ◽  
High Degree

AbstractThe California Serogroup (CSG) of Orthobunyaviruses comprises several viruses capable of causing neuroinvasive disease in humans, including La Crosse (LACV), Snowshoe Hare (SSHV), Tahyna (TAHV), Jamestown Canyon (JCV), and Inkoo (INKV) viruses. Diagnosis of specific CSG viruses is complicated by the high degree of antibody cross-reactivity between them, with laboratory standards requiring a fourfold higher titer of neutralizating antibody (NAb) activity to positively identify the etiologic virus. To help elucidate NAb relationships between neuroinvasive CSG viruses, we directly compared the cross-reactivity of NAb between LACV, SSHV, TAHV, JCV, and INKV. Mice were inoculated with individual viruses and the NAb activity of plasma samples was compared by plaque reduction neutralization tests against all five viruses. Overall, the results from these studies show that the CSG viruses induced high levels of NAb against the inoculum virus, and differing amounts of cross-reactive NAb against heterologous viruses. LACV, SSHV, and INKV elicited the highest amount of cross-reactive NAb. Interestingly, a fourfold difference in NAb titer between the inoculum virus and the other CSG viruses was not always observed. Thus, NAb titers, which are the gold-standard for diagnosing the etiologic agent for viral encephalitis, may not clearly differentiate between different CSG viruses.

scholarly journals Hyper-Aerotolerant Campylobacter coli from Duck Sources and Its Potential Threat to Public Health: Virulence, Antimicrobial Resistance, and Genetic Relatedness

2019 ◽  
Vol 7 (11) ◽  
pp. 579 ◽  
Author(s):  
Jae-Ho Guk ◽  
Junhyung Kim ◽  
Hyokeun Song ◽  
Jinshil Kim ◽  
Jae-Uk An ◽  
...  
Keyword(s):  
Public Health ◽  
Antimicrobial Resistance ◽  
Inhibitory Concentration ◽  
Genetic Relatedness ◽  
Control Strategies ◽  
Campylobacter Coli ◽  
Potential Threat ◽  
High Level ◽  
Sequence Types ◽  
Level Resistance

Campylobacter, a common foodborne human pathogen, is considered sensitive to oxygen. Recently, aerotolerant (AT) Campylobacter jejuni with the ability to survive under aerobic stress has been reported. Here, we investigated the prevalence of hyper-aerotolerant (HAT) Campylobacter coli from duck sources (118 carcasses and meat) and its characteristics to assess potential impacts on public health. Half of 56 C. coli isolates were HAT and most harbored various virulence genes including flaA, cadF, cdtA, ceuB, and wlaN. Moreover, 98.2% of C. coli isolates showed resistance to quinolones, including ciprofloxacin (CIP), and nine (16.1%) showed high-level resistance to ciprofloxacin (Minimum Inhibitory Concentration, MIC ≥ 32 μg/mL) and most of these were HAT. Based on genetic relatedness between C. coli from duck sources and those from human sources (PubMLST and NCBI), HAT isolates sharing the same MLST sequence types were significantly more prevalent than those not sharing the same sequence types as those from human sources. Therefore, HAT C. coli is prevalent in duck sources, and is most likely transmitted to humans through the food chain given its aerotolerance. This being so, it might pose a threat to public health given its virulence and antimicrobial resistance (AMR). This study will assist in improving control strategies to reduce farm-to-table HAT C. coli transmission to humans.

scholarly journals Genetic Relatedness and Superantigen Expression in Group A Streptococcus Serotype M1 Isolates from Patients with Severe and Nonsevere Invasive Diseases

2000 ◽  
Vol 68 (6) ◽  
pp. 3523-3534 ◽  
Author(s):  
Sonia Chatellier ◽  
Nahla Ihendyane ◽  
Rita G. Kansal ◽  
Farukh Khambaty ◽  
Hesham Basma ◽  
...  
Keyword(s):  
Disease Severity ◽  
Genetic Relatedness ◽  
Group A Streptococcus ◽  
Phenotypic Expression ◽  
Invasive Disease ◽  
Banding Patterns ◽  
Clinical Criteria ◽  
Group A ◽  
High Degree ◽  
Culture Supernatants

ABSTRACT The relatedness of group A streptococcal (GAS) strains isolated from 35 Canadian patients with invasive disease of different severity was investigated by a variety of molecular methods. All patients were infected with M1T1 strains and, based on clinical criteria, were classified as severe (n = 21) and nonsevere (n = 14) invasive GAS infection cases. All the M1 strains studied had the emm1.0 allele and the same streptococcal pyrogenic exotoxin (Spe) genotype,speA+ speB+ speC speF+speG+ speH smeZ+ ssa. All isolates had the same speA allotype, speA2. The randomly amplified polymorphic DNA banding pattern with two different primers was identical for all strains, and pulsed field gel electrophoresis analysis showed that 33 and 30 isolates had identical banding patterns after DNA digestion with SfiI or SmaI, respectively; the nonidentical isolates differed from the main pattern by only one band. A relatively high degree of polymorphism in specific regions of the sic gene was observed among isolates; however, this polymorphism was not associated with disease severity. Likewise, although the phenotypic expression of SpeA, SpeB, and SpeF proteins varied among the M1T1 isolates, there was no correlation between the amount of Spe expressed and disease severity. Importantly, mitogenic and cytokine responses induced by partially purified bacterial culture supernatants containing a mixture of expressed superantigens were very similar for isolates from severe and nonsevere cases (P > 0.1). Together, the data indicate that highly related invasive M1T1 isolates, some indistinguishable, can cause disease of varying severity in different individuals. These findings underscore the contribution of host factors to the outcome of invasive GAS infections.

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