scholarly journals Molecular Epidemiological Characterization of Staphylococcus argenteus Clinical Isolates in Japan: Identification of Three Clones (ST1223, ST2198, and ST2550) and a Novel Staphylocoagulase Genotype XV

2019 ◽  
Vol 7 (10) ◽  
pp. 389 ◽  
Author(s):  
Aung ◽  
Urushibara ◽  
Kawaguchiya ◽  
Sumi ◽  
Takahashi ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Clonal Diversity ◽  
Clinical Isolates ◽  
High Sequence Identity ◽  
Genetic Characteristics ◽  
Single Locus Variant ◽  
Binding Protein Gene ◽  
A Minor ◽  
Epidemiological Characterization

Staphylococcus argenteus, a novel emerging species within Staphylococcus aureus complex (SAC), has been increasingly reported worldwide. In this study, prevalence of S. argenteus among human clinical isolates, and their clonal diversity and genetic characteristics of virulence factors were investigated in Hokkaido, the northern main island of Japan. During a four-month period starting from March 2019, twenty-four S. argenteus and 4330 S. aureus isolates were recovered from clinical specimens (the ratio of S. argenteus to S. aureus :0.0055). Half of S. argenteus isolates (n = 12) belonged to MLST sequence type (ST) 2250 and its single-locus variant, with staphylocoagulase genotype (coa-) XId, while the remaining isolates were assigned to ST2198/coa-XIV (n = 6), and ST1223 with a novel coa-XV identified in this study (n = 6). All the isolates were mecA-negative, and susceptible to all the antimicrobials tested, except for an ST2198 isolate with blaZ and an ST2250 isolate with tet(L) showing resistance to ampicillin and tetracyclines, respectively. Common virulence factors in the S. argenteus isolates were staphylococcal enterotoxin (-like) genes sey, selz, sel26, and sel27 in ST2250, selx in ST2198, and enterotoxin gene cluster (egc-1: seg-sei-sem-sen-seo) in ST1223 isolates, in addition to hemolysin genes (hla, hlb, and hld) distributed universally. Elastin binding protein gene (ebpS) and MSCRAMM family adhesin SdrE gene (sdrE) detected in all the isolates showed high sequence identity among them (> 97%), while relatively lower identity to those of S. aureus (78–92%). Phylogenetically, ebpS, sdrE, selx, sey, selw, sel26, and sel27 of S. argenteus formed clusters distinct from those of S. aureus, unlike sec, selz, tst-1, and staphylokinase gene (sak). The present study revealed the prevalence of S. argenteus among clinical isolates, and presence of three distinct S. argenteus clones (ST2250; ST2198 and ST1223) harboring different virulence factors in northern Japan. ST2198 S. argenteus, a minor clone (strain BN75-like) that had been rarely reported, was first identified in Japan as human isolates.

scholarly journals Application of kDNA Minicircle PCR-RFLP to Characterize Leishmania donovani Clinical Isolates Obtained from Post-Kala-Azar Dermal Leishmaniasis in Eastern Nepal

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Ojesh Pokhrel ◽  
Keshav Rai ◽  
Narayan Raj Bhattarai ◽  
Suman Rijal ◽  
Arpana Rijal ◽  
...  
Keyword(s):  
Leishmania Donovani ◽  
Clinical Isolates ◽  
Rdna Genes ◽  
Kala Azar ◽  
Pcr Rflp ◽  
Potential Reservoir ◽  
Rflp Assay ◽  
Epidemiological Characterization

Post-kala-azar dermal leishmaniasis (PKDL) is a skin manifestation of visceral leishmaniasis (VL) which develops after apparent cure in some patients. PKDL is considered as the potential reservoir for the VL infection. Molecular epidemiological characterization of L. donovani isolates obtained from VL and PKDL isolates is essentially required in order to understand the transmission dynamics of the VL infection. To date, genetic variation among the VL and PKDL L. donovani isolates was not fully elucidated. Therefore, 14 clinical isolates from VL and 4 clinical isolates from PKDL were speciated by hsp70 and rDNA genes. Further characterization of L. donovani by haspB PCR demonstrates two different genotypes. All PKDL isolates have the same genetic structure. kDNA PCR-RFLP assay revealed 18 different genotypes; however, structural analysis showed the two distinct kDNA genotype population (k = 2). The kDNA fingerprint patterns of parasites from hilly districts were clustered separately from low-land districts. Therefore, further study with a large number of samples is urgently required for systematic characterization of the clinical isolates to track the molecular epidemiology of the Leishmania donovani causing VL and the role of PKDL as a reservoir.

scholarly journals Characterization of Virulence Factors in Enterotoxin-Producing Staphylococcus Aureus From Bulk Tank Milk

2021 ◽  
Author(s):  
Hye-Ri Jung ◽  
Young Ju Lee
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Bovine Mastitis ◽  
Bulk Tank Milk ◽  
Genetic Characteristics ◽  
Enterotoxin Genes ◽  
High Prevalence ◽  
Bulk Tank

Abstract Background: Staphylococcus aureus, a persistent and chronic mastitis-causing pathogen, produces various virulence factors, including enterotoxins. This study analyzed the genetic characteristics of bovine mastitis-related virulence factors to evaluate potential pathogenesis in S. aureus isolated from bulk tank milk.Results: Among 93 S. aureus isolates from 396 dairy farms in six factories operated by three dairy companies in Korea, 40 (43.0%) isolates carried at least one or more enterotoxin genes and there were significant differences between factories within the same company (p < 0.05). Moreover, S. aureus carrying enterotoxin genes showed a higher prevalence in all virulence genes tested in this study except for pvl and lukM, which were not detected in any isolate, than the isolates without enterotoxin genes. In particular, the prevalence of six genes (hla, hlb, lukED, fnbA, clfA, and clfB) was significantly higher in S. aureus carrying enterotoxin genes than isolates without enterotoxin genes (p < 0.05). The most common multilocus sequence type (ST) of 40 enterotoxin-producing isolates was ST188, and all isolates of ST188 harbored the see gene. However, none of the isolates of ST1 and ST72 carried the see gene, and all isolates of ST1 carried the seh gene.Conclusions: Although S. aureus isolated from bulk tank milk, not from mastitis, had a high prevalence of enterotoxins and virulence factors simultaneously, posing a public health threat. Moreover, high enterotoxins in bulk tank milk may be reflected by poor hygiene; therefore, it is important to develop strong monitoring and sanitation programs to ensure that dairy factories produce hygienic milk.

scholarly journals Distribution of Virulence Factors and Resistance Determinants in Three Genotypes of Staphylococcus argenteus Clinical Isolates in Japan

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 163
Author(s):  
Meiji Soe Aung ◽  
Noriko Urushibara ◽  
Mitsuyo Kawaguchiya ◽  
Mina Hirose ◽  
Miyo Ike ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Virulence Factors ◽  
Detection Rate ◽  
Wide Spectrum ◽  
Clinical Isolates ◽  
Genetic Characteristics ◽  
Staphylococcal Species ◽  
Resistance Determinants ◽  
Major Cluster ◽  
Drug Resistance Profile

Staphylococcus argenteus, a novel staphylococcal species independent of S. aureus, causes a wide spectrum of infectious diseases. As detection of this species from humans and animals has been increasingly reported worldwide, its growing virulence and drug resistance via external genetic determinants has become concerning. In this study, the prevalence and genetic characteristics of virulence factors and drug resistance determinants were investigated for 82 S. argenteus clinical isolates in Hokkaido, Japan, for a one-year period starting in August 2019. These S. argenteus isolates corresponded to 0.66% of the total number of S. aureus isolates collected in the same period. The most prevalent genotype was sequence type (ST) 2250 and staphylocoagulase (coa) genotype XId (45.1%, n = 37), followed by ST1223-coa XV (30.5%, n = 25) and ST2198-coa XIV (24.4%, n = 20). Panton-Valentine leukocidin genes (lukS-PV-lukF-PV) were identified in a single ST2250 isolate. Only ST1223 isolates had the enterotoxin gene cluster (egc-2), seb, and selw (detection rate; 100%, 60%, and 84%, respectively), while sec, sey, sel26-sel27, tst-1 were only detected in ST2250 isolates (detection rate; 10.8%, 100%, 67.6%, and 10.8%, respectively). ST2198 isolates harbored selx at a significantly higher rate (60%) than isolates of other STs. Although most of S. argenteus isolates were susceptible to antimicrobials examined, ST2198 showed higher resistance rates to penicillin, macrolides, and aminoglycosides than other STs, and it harbored various resistance genes such as blaZ, erm(C), msr(A), lnuA, and aac(6′)-Ie-aph(2″)-Ia. Only one ST2250 isolate possessed SCCmec-IVc, showing resistance to oxacillin. blaZ was the most prevalent determinant of resistance in the three STs and belonged to two plasmid groups and a chromosomal group, suggesting its diverse origin. lnu(A) in ST2198 isolates was assigned to a major cluster with various staphylococcal species. The present study indicates that the prevalence of virulence factors and drug resistance profile/determinants differ depending on the lineage (ST) of S. argenteus.

scholarly journals Characterization of virulence factors and clonal diversity of Enterococcus faecalis isolates from treated dental root canals

2011 ◽  
Vol 162 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Gustavo O. Zoletti ◽  
Eliezer M. Pereira ◽  
Ricardo P. Schuenck ◽  
Lúcia M. Teixeira ◽  
José F. Siqueira ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Virulence Factors ◽  
Clonal Diversity ◽  
Root Canals

Epidemiological Characterization of the Infection by Treponema Pallidum in Pregnant Women in Beira City, Sofala, Mozambique

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Nchowela Guido
Keyword(s):  
Pregnant Women ◽  
Congenital Syphilis ◽  
Health Centre ◽  
Treponema Pallidum ◽  
Timely Manner ◽  
Pregnancy And Childbirth ◽  
Epidemiological Characterization ◽  
Active Syphilis ◽  
Structured Questionnaire

Introduction: Syphilis is one of several diseases that can be transmitted during pregnancy and childbirth, which can lead to complications during pregnancy and in the newborn. This is especially so when the pregnant woman is not diagnosed or treated properly and in a timely manner. Methodology: Data from 262 pregnant women prospectively included, aged 18-41years, attended at the Ponta Gêa Health Centre for antenatal clinics has been analyzed from January to September of 2016. In the prospective study, a rapid treponemal and a non-treponemal test were performed. A structured questionnaire was used to collect socio demographic and clinical variables, which was developed from the literature review. Results: The prevalence of active syphilis was 11.8%; the majority of reactive pregnant women were aged 18-25years (55.4%), (61.3%) of pregnant women were treated with doses below those recommended; only a small number of the partners were treated successfully. The highest seroprevalence of syphilis was found in housewives (77%), in those who attended primary education (71.6%) in those who had a monthly income of 1000- 3000 MZN (70.3%), in those with two or more pregnancies (55.7%) and living with someone has husband and wife (63.5%). The syphilis/HIV co-infection rate was high. Conclusion: According to the results obtained in this study, urgent measures are needed to assess the problems encountered and to improve the screening approach, treatment and monitoring of syphilis during pregnancy in order to prevent the cases of congenital syphilis.

scholarly journals Phenotypic and molecular characterization of Acinetobacter baumannii clinical isolates in Saudi Arabia

2020 ◽  
Vol 13 (2) ◽  
pp. 327
Author(s):  
R Bawazeer ◽  
M Algoribi ◽  
T Abujamel ◽  
L Okdah ◽  
M Alzayer ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Acinetobacter Baumannii ◽  
Molecular Characterization ◽  
Clinical Isolates
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