M genotyping and DNA fingerprinting of Streptococcus 
pyogenes isolates from an area of central Italy

M protein gene typing was used to analyse Streptococcus pyogenes clinical isolates collected between 1983 and 1995 in an area of central Italy from patients presenting different types of infections; the same isolates were also characterized by means of DNA fingerprinting.M type 1 was the most common (50% of study strains), followed by M types 4, 12 and 6. The proportion of M type 12 decreased with time, whereas M type 1 increased, in agreement with data obtained in many different areas. Most invasive strains belonged to types M1 (30%) and M12 (30%); on the other hand, the M1 type did frequently occur also among non-invasive isolates. DNA fingerprinting showed a correlation between M types and DNA patterns. This report provides epidemiological information from a geographic area not sampled recently, and further shows the usefulness of the M genotyping technique, which offers potential advantages over conventional serological typing methods.

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Distribution of virulence genes and the molecular epidemiology of Streptococcus pyogenes clinical isolates by emm and multilocus sequence typing methods

10.21203/rs.3.rs-44181/v1 ◽

2020 ◽

Author(s):

Siti Nur Adila Hamzah ◽

Mohd Nasir Mohd Desa ◽

Azmiza Syawani Jasni ◽

Niazlin Mohd Taib ◽

Siti Norbaya Masri ◽

...

Keyword(s):

Molecular Epidemiology ◽

Virulence Factors ◽

Streptococcus Pyogenes ◽

Multilocus Sequence Typing ◽

Virulence Genes ◽

Clinical Samples ◽

Pcr Analysis ◽

Gold Standard Method ◽

Non Invasive ◽

Typing Methods

Abstract Background: Streptococcus pyogenes has a variety of virulence factors and the predominant invasive strains differ according to specific emm types and geographical orientation. Although emm typing is commonly used as the gold standard method for the molecular characterization, multilocus sequence typing (MLST) has become an important tool for comparing the genetic profiles globally. This study aimed to screen selected virulence genes from invasive and non-invasive clinical samples and to characterize the molecular epidemiology by emm typing and MLST methods. Methods: A total of 42 S. pyogenes isolates from invasive and non-invasive samples collected from 2014 to 2015 from two different tertiary hospitals were investigated for the distribution of virulence factors and their molecular epidemiology by emm and multilocus sequence typing methods. Detection of five virulence genes (speA , speB , speJ , ssa and sdaB) was performed using multiplex polymerase chain reaction (PCR) using the standard primers and established protocol. Results: Multiplex PCR analysis revealed that sdaB/speF (78.6%) and speB (61.9%) were the predominant virulence genes. Regardless of the type of invasiveness, diverse distribution of emm types/subtypes was noted which comprised of 27 different emm types/subtypes. The predominant emm types/subtypes were emm63 and emm18 with each gene accounted for 11.8% whereas 12% for each gene was noted for emm28, emm97.4 and emm91. The MLST revealed that the main sequence type (ST) in invasive samples was ST402 (17.7%) while ST473 and ST318 (12% for each ST) were the major types in non-invasive samples. Out of 18 virulotypes, Virulotype A (five genes, 55.6%) and Virulotype B (two genes, 27.8%) were the major virulotypes found in this study. Phylogenetic analysis indicated the presence of seven different clusters of S. pyogenes. Interestingly, Cluster VI showed that selected emm/ST types such as emm71/ST318 (n=2), emm70.1/ST318 (n=1), emm44/ST31 (n=1) and emm18/ST442 (n=1) have clustered within a common group (Virulotype A) for both hospitals studied. Conclusion: The present study showed that group A streptococci (GAS) are genetically diverse and possess virulence genes regardless of their invasiveness. Majority of the GAS exhibited no restricted pattern of virulotypes except for a few distinct clusters. Therefore, it can be concluded that virulotyping is partially useful for characterizing a heterogeneous population of GAS in hospitals.

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Comparison of biochemical and serological typing results and antimicrobial susceptibility patterns in the epidemiological investigation of Klebsiella spp

Epidemiology and Infection ◽

10.1017/s0950268800066474 ◽

1987 ◽

Vol 99 (3) ◽

pp. 625-634 ◽

Cited By ~ 1

Author(s):

A. M. Simoons-Smit ◽

A. M. J. J. Verweij-Van Vught ◽

P. M. J. M. De Vries ◽

D. M. Maclaren

Keyword(s):

Antimicrobial Susceptibility ◽

Clinical Isolates ◽

Epidemiological Investigation ◽

Serological Typing ◽

Typing Methods ◽

Environmental Surveys ◽

Klebsiella Spp ◽

Neonatal Ward ◽

Susceptibility Patterns ◽

Epidemiological Information

SUMMARYAn analysis of the serological and biochemical typing results of 925 clinical isolates of klebsiella revealed that biotyping and serotyping of klebsiella could replace each other for epidemiological purposes. The combination of both typing methods provided even more epidemiological information in analysing clusters of particular serotypes and biotypes in time. Clustering serotypes, mainly of neonatal origin, were nearly uniformly more resistant to the antibiotics in common use than other serotypes. Biotyping as well as serotyping of klebsiella isolates recovered from environmental surveys in the neonatal ward showed that epidemic and non-epidemic klebsiella isolates could occasionally be cultured from the environment and from the staff.

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EVALUATION OF ANTIMICROBIAL SUSCEPTIBILITY AND SEROLOGICAL TYPING OF STREPTOCOCCUS PYOGENES ISOLATED IN CHILDREN WITH INVASIVE DISEASE FROM A TERTIARY HOSPITAL IN MADRID

10.26226/morressier.58fa1766d462b80290b508e1 ◽

2017 ◽

Author(s):

Lucía Marcela Figueroa Ospina

Keyword(s):

Streptococcus Pyogenes ◽

Antimicrobial Susceptibility ◽

Tertiary Hospital ◽

Invasive Disease ◽

Serological Typing

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Association between central non-dipping pattern and platelet morphology in adults with type 1 diabetes without cardiovascular disease: a cross-sectional study

Scientific Reports ◽

10.1038/s41598-021-94414-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Michal Kulecki ◽

Dariusz Naskret ◽

Mikolaj Kaminski ◽

Dominika Kasprzak ◽

Pawel Lachowski ◽

...

Keyword(s):

Blood Pressure ◽

Type 1 Diabetes ◽

Smoking Status ◽

Cross Sectional Study ◽

Cross Sectional ◽

Distribution Width ◽

Non Invasive ◽

Platelet Morphology ◽

Oscillometric Device

AbstractThe non-dipping pattern is nighttime systolic blood pressure (SBP) fall of less than 10%. Several studies showed that the non-dipping pattern, increased mean platelet volume (MPV), and platelet distribution width (PDW) are associated with elevated cardiovascular risk. Hypertensives with the non-dipping pattern have higher MPV than the dippers but this relationship was never investigated among people with type 1 diabetes mellitus (T1DM). This study aimed to investigate the association between the central dipping pattern and platelet morphology in T1DM subjects. We measured the central and brachial blood pressure with a validated non-invasive brachial oscillometric device—Arteriograph 24—during twenty-four-hour analysis in T1DM subjects without diagnosed hypertension. The group was divided based on the central dipping pattern for the dippers and the non-dippers. From a total of 62 subjects (32 males) aged 30.1 (25.7–37) years with T1DM duration 15.0 (9.0–20) years, 36 were non-dippers. The non-dipper group had significantly higher MPV (MPV (10.8 [10.3–11.5] vs 10.4 [10.0–10.7] fl; p = 0.041) and PDW (13.2 [11.7–14.9] vs 12.3 [11.7–12.8] fl; p = 0.029) than dipper group. Multivariable logistic regression revealed that MPV (OR 3.74; 95% CI 1.48–9.45; p = 0.005) and PDW (OR 1.91; 95% CI 1.22–3.00; p = 0.005) were positively associated with central non-dipping pattern adjusting for age, sex, smoking status, daily insulin intake, and height. MPV and PDW are positively associated with the central non-dipping pattern among people with T1DM.

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Intra- and Interspecies Signaling betweenStreptococcus salivarius and Streptococcus pyogenes Mediated by SalA and SalA1 Lantibiotic Peptides

Journal of Bacteriology ◽

10.1128/jb.183.13.3931-3938.2001 ◽

2001 ◽

Vol 183 (13) ◽

pp. 3931-3938 ◽

Cited By ~ 99

Author(s):

M. Upton ◽

J. R. Tagg ◽

P. Wescombe ◽

H. F. Jenkinson

Keyword(s):

Streptococcus Pyogenes ◽

Response Regulator ◽

Genetic Locus ◽

Two Component System ◽

Peptide Modification ◽

Insertional Inactivation ◽

Two Component ◽

Genes Encoding ◽

Dose Dependent

ABSTRACT Streptococcus salivarius 20P3 produces a 22-amino-acid residue lantibiotic, designated salivaricin A (SalA), that inhibits the growth of a range of streptococci, including all strains ofStreptococcus pyogenes. Lantibiotic production is associated with the sal genetic locus comprisingsalA, the lantibiotic structural gene; salBCTXgenes encoding peptide modification and export machinery proteins; andsalYKR genes encoding a putative immunity protein and two-component sensor-regulator system. Insertional inactivation ofsalB in S. salivarius 20P3 resulted in abrogation of SalA peptide production, of immunity to SalA, and ofsalA transcription. Addition of exogenous SalA peptide tosalB mutant cultures induced dose-dependent expression ofsalA mRNA (0.2 kb), demonstrating that SalA production was normally autoregulated. Inactivation of salR encoding the response regulator of the SalKR two-component system led to reduced production of, and immunity to, SalA. The sal genetic locus was also present in S. pyogenes SF370 (M type 1), but because of a deletion across the salBCT genes, the corresponding lantibiotic peptide, designated SalA1, was not produced. However, in S. pyogenes T11 (M type 4) the sallocus gene complement was apparently complete, and active SalA1 peptide was synthesized. Exogenously added SalA1 peptide from S. pyogenes T11 induced salA1 transcription in S. pyogenes SF370 and in an isogenic S. pyogenes T11salB mutant and salA transcription in S. salivarius 20P3 salB. Thus, SalA and SalA1 are examples of streptococcal lantibiotics whose production is autoregulated. These peptides act as intra- and interspecies signaling molecules, modulating lantibiotic production and possibly influencing streptococcal population ecology in the oral cavity.

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Non invasive mechanical ventilation in myotonic dystrophy type 1? Hypoventilation versus quality of life perspective

Neuromuscular Disorders ◽

10.1016/j.nmd.2017.11.019 ◽

2018 ◽

Vol 28 (2) ◽

pp. 193

Author(s):

Giuseppe Fiorentino ◽

Antonio M. Esquinas

Keyword(s):

Quality Of Life ◽

Mechanical Ventilation ◽

Myotonic Dystrophy ◽

Invasive Mechanical Ventilation ◽

Myotonic Dystrophy Type 1 ◽

Myotonic Dystrophy Type ◽

Non Invasive

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Measurement of corneal thickness, optic nerve sheath diameter and retinal nerve fiber layer as potential new non-invasive methods in assessing a risk of cerebral edema in type 1 diabetes in children

Acta Diabetologica ◽

10.1007/s00592-018-1242-8 ◽

2018 ◽

Vol 55 (12) ◽

pp. 1295-1301 ◽

Cited By ~ 9

Author(s):

Krzysztof Jeziorny ◽

Anna Niwald ◽

Agnieszka Moll ◽

Katarzyna Piasecka ◽

Aleksandra Pyziak-Skupien ◽

...

Keyword(s):

Type 1 Diabetes ◽

Optic Nerve ◽

Corneal Thickness ◽

Optic Nerve Sheath Diameter ◽

Study Group ◽

Newly Diagnosed ◽

Fiber Layer ◽

Non Invasive ◽

Nerve Sheath

Abstract Aims Some patients with diabetic ketoacidosis develop cerebral edema (CE) in the course of type 1 diabetes mellitus (T1D), which may result in central nervous system disorders and high mortality. The imperfection of existing neuroimaging techniques for early recognition of CE forces us to search for the new and non-invasive methods. The aim of the study was to assess the usefulness of new methods (pachymetry, transorbital ultrasonography—USG, optical coherence tomography—OCT study) in the assessment of the risk of CE occurrence in children with newly diagnosed T1D. Methods The study group included 50 children with newly diagnosed T1D, 54 patients with long-term T1D as a reference group and 40 children without glucose tolerance disorders as controls. In all subjects, a corneal thickness (CCT) index with pachymeter, optic nerve sheath diameter (ONSD) using transorbital USG and retinal nerve fiber layer (RNFL) during OCT study were measured and compared with selected clinical parameters of T1D. Results In patients from a study group at onset of T1D, the higher CCT (p < 0.001) and ONSD (p < 0.001) values were observed as compared to the results obtained after 48 h of metabolic compensation. The ONSD correlated negatively with pH value (r = − 0.64; p < 0.001), BE (r = − 0.54, p < 0.001) and HCO3− (r = − 0.50; p < 0.001). A positive correlation between RNFL and Na+ levels (r = 0.47; p < 0.005) was also observed. Conclusions Transorbital USG and pachymetry may serve as the potential promising methods for the non-invasive assessment of the increased risk of development of CE in patients with T1D.

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