Cluster of cases due to Shigella flexneri producing CTX-M-15 in Spain.

The aim of our study was to delineate an outbreak of gastroenteritis caused by Shigella flexneri and affecting sixteen persons between May and June 2014 in Bilbao, Spain. All patients exhibited symptoms after consuming kebab in the same kebab shop.The outbreak is described through the clinical cases, the microbiological and molecular genetic diagnosis, and the epidemiologic investigation. Minimum inhibitory concentrations for ampicillin, amoxicillin plus clavulanic acid, third and fourth generation cephalosporins, carbapenems, monobactams, aminoglycosides, fluoroquinolones, co-trimoxazole, colistin and tigecycline were measured. The S. flexneri strains were screened by PCR for TEM, SHV, CTX-M beta-lactamases and plasmidic AmpCs and aac(6')-Ib gene. Serotyping, pulsed field gel-electrophoresis, conjugation assay, plasmid sizing by S1 enzyme digestion and Southern blot hybridization were accomplished.All the S. flexneri isolates proved to be serotype 2 and produced extended-spectrum beta-lactamase (ESBL). Carbapenems, fluoroquinolones, tigecycline, colistin, and co-trimoxazole remained active antibiotics. All the strains harboured blaCTX-M-15 and blaOXA-1 genes. The strains hosted two high-molecular weight plasmids of 100 and 230 kb, respectively. According to the hybridization assay blaCTX-M-15 was located on the plasmid of 230 kb. The identical pulsotype verified the presence of outbreak.Remarkable, that one of the food handlers has travelled recently to Pakistan, where ESBL-producing Shigella strains had been reported previously. To the best of our knowledge, this is the first outbreak caused by CTX-M-15-expressing S. flexneri in Spain and as well as in Europe.

Co-infection by two linezolid-resistant coagulase-negative staphylococci with two different resistance determinants.

Linezolid resistance among Gram-positive pathogens is being reported with increasing frequency. We examined 14 linezolid-resistant coagulase-negative staphylococci (CoNS) isolated from blood cultures obtained from patients admitted to the Intensive Care Unit of Vicenza General Hospital, Italy. The species identification yielded 10 Staphylococcus epidermidis, 3 Staphylococcus hominis, and 1 Staphylococcus capitis. Minimal inhibitory concentrations of linezolid ranged between 16 and 32 mg/l. By sequencing domain V of the 23S rRNA gene, 4 isolates were found to harbour a G2576T mutation and 10 isolates a G2447T mutation. None of the strains under study presented either the cfr gene or cardinal mutations in the L3, L4, or L22 riboproteins. In this clinical collection of linezolid-resistant CoNS the G2447T mutation was dominantly associated with S. epidermidis, while the G2576T mutation was found in other CoNS species. Two different CoNS species endowed with either mutation were isolated from 2 patients.

Transfer of radionuclides from soil to Acacia auriculiformis trees in high radioactive background areas in North Vietnam.

The Acacia auriculiformis is a tree common in tropical Asian countries, capable of growing in many different soil types, so it could be used for biomonitoring for high natural radionuclide areas in tropical and subtropical climates. The transfer factor (TF) of radionuclides from soil to A. auriculiformis in eight uranium and rare earth element (REE) mining areas of North Vietnam was investigated. The activity concentrations 226Ra, 238U, 137Cs, 228Ra, and 40K in both soil and A. auriculiformis showed considerable variation. The TFs of these radionuclides also varied in a wide range. In most of the eight areas, the highest TF was observed for 137Cs and 228Ra. While the TFs for 226Ra and 238U were smallest. In addition, the TFs for radionuclides near REE mines were similar to those observed near uranium mines. The TFs for A. auriculiformis were within the ranges of TF reported for other plants, except for 137Cs.

Study of Well Waters from High-Level Natural Radiation Areas in Northern Vietnam.

The determination of natural radionuclide concentrations plays an important role for assuring public health and in the estimation of the radiological hazards. This is especially true for high level radiation areas. In this study, 226Ra, 228Ra and 238U concentrations were measured in well waters surrounding eight of the high-level natural radiation areas in northern Vietnam. The 226Ra, 228Ra and 238U activity concentrations vary from <1.2 × 10-3-2.7 (0.46), <2.6 × 10-3-0.43 (0.07) and <38 × 10-3-5.32 Bq/L (0.50 of median), respectively. 226Ra and 238U isotopes in most areas are in equilibrium, except for the DT-Thai Nguyen area. The calculated radiological hazard indices are generally higher than WHO (World Health Organization) recommendations. Average annual effective dose and excess lifetime cancer risk values due to drinking well water range from to 130 to 540 µSv/year and 7.4 × 10-6 to 3.1 × 10-5, respectively.

Relationship between arterial stiffness and regular physical activity / Az artériás érfali merevség és a rendszeres testmozgás kapcsolata.

Összefoglaló. A cardiovascularis megbetegedések kialakulását és progresszióját jelentosen befolyásolja az életmód, ezen belül a fizikai aktivitás. A rendszeres testmozgás csökkenti a szív- és érrendszeri kórképek kockázatát, többek között a magas vérnyomásra, a zsíranyagcsere-eltérésekre és az elhízásra gyakorolt kedvezo hatásán keresztül, továbbá független tényezo a cardiovascularis halálozás szempontjából is. Az artériás érfali merevség az elasztikus artériák falát alkotó extracelluláris mátrix degeneratív eltéréseinek következtében alakul ki a különbözo kockázati tényezok hatására. Korábban, különbözo populációkon már igazolták az érfali merevség prediktív értékét a cardiovascularis események kialakulásának tekintetében. A pulzushullám-terjedési sebesség mérése a leggyakrabban alkalmazott módszer az érfali merevség meghatározására. A pulzushullám-terjedési sebesség mérésének hasznát a cardiovascularis kimenetel és élettartam becslésében számos populációs szintu követéses vizsgálat igazolja. Jelen munkánkban áttekintjük a rendszeres fizikai aktivitás, az érfali merevség, az érelmeszesedés és a cardiovascularis események közötti összefüggéseket. Összefoglaljuk az edzésnek és az érfali merevség paramétereinek kapcsolatát egészséges populáción vizsgáló legfontosabb tanulmányok eredményeit. Megállapítjuk, hogy az érfali merevség figyelemre méltó, érdekes biomarker a cardiovascularis kockázat becslése során a rendszeresen sportoló személyek esetén is. Mindezek alapján, tekintve annak prognosztikai hasznát, felmerül a pulzushullám-terjedési sebesség mérésének beillesztése a klinikai döntéshozatali folyamatba mind amator, mind professzionális sportolók esetében. Orv Hetil. 2021; 162(16): 615-622. Summary. The development and progression of cardiovascular disorders is importantly dependent on lifestyle factors, including physical activity. Regular physical activity decreases cardiovascular morbidity by ameliorating risk factors such as hypertension, dyslipidemia and obesity, moreover, also independently affects cardiovascular mortality. Arterial stiffness results from a degenerative process affecting mainly the extracellular matrix of elastic arteries under the effect of risk factors. Previously, the independent predictive value of arterial stiffness for cardiovascular events has been demonstrated in various populations. Pulse wave velocity is the most commonly used method for the assessment of arterial stiffness. The value of measuring pulse wave velocity to predict cardiovascular health outcomes and longevity has been established in several population-based longitudinal studies. In this review, we summarize the main associations between regular physical exercise, arterial stiffness, atherosclerotic burden and incident cardiovascular events. We cite findings from the major studies focusing on the effect of training on arterial stiffness parameters in healthy subjects. We conclude that arterial stiffness is emerging as an interesting biomarker for cardiovascular risk stratification in subjects doing regular physical activity. Therefore, the incorporation of pulse wave velocity measurement into clinical decision-making could be indicated in the case of both amateur and professional athletes, given the prognostic information it provides. Orv Hetil. 2021; 162(16): 615-622.

Natural radioactivity and radiological risks of common building materials used in Semnan Province dwellings, Iran.

Impact assessment of building materials is a focused topic in the field of radioecology. A radiological survey has conducted to monitor radioactivity of most common building materials in Semnan Province, Iran, and assess the radiation risk. Activity concentrations of 226Ra, 232Th, and 40K were measured in 29 samples including nine commonly used building materials that were collected from local suppliers and manufacturers, using a high purity germanium gamma-ray detector. The activity concentrations of 226Ra, 232Th, and 40K varied from 6.7±1 to 43.6±9, 5.9±1 to 60±11, and 28.5±3 to 1085±113 Bq kg-1 with averages of 26.8±5, 22.7±4, and 322.4±4 Bq kg-1, respectively. By applying multivariate statistical approach (Pearson correlation, cluster, and principal component analyses (PCA)), the radiological health hazard parameters were analyzed to obtain similarities and correlations between the various samples. The Pearson correlation showed that the 226Ra distribution in the samples is controlled by changing the 232Th concentration. The variance of 95.58% obtained from PCA resulted that the main radiological health hazard parameters exist due to the concentration of 226Ra and 232Th. The resulting dendrogram of cluster analysis also shows a well coincidence with the correlation analysis.

Comparison of Austrian, Hungarian and Macedonian methicillin-resistant and methicillin-sensitive Staphylococcus aureus strains in relation to prevalence of cytotoxin genes.

Cytotoxin genes in 128 Austrian (AT) MSSA, 48 MRSA, 94 Hungarian (HU) MSSA, 110 MRSA and 67 Macedonian (MK) MSSA, 81 MRSA strains were examined. The presence of alfa-haemolysin gene (hla) was more common in HU MSSA strains compared to AT and MK (99%, 86%, 72%: p<0.001). AT and MK MRSA harboured hlb genes more frequently compared to HU (60%, 62%, 33%: p<0.001). HU and MK MRSA strains carried gamma-haemolysin gene (hlg) in higher percentage in contrast to AT (88%, 83%, 69%: p=0.01). Haemolysin gamma-variant gene (hlgv) was more prevalent in HU MSSA compared to AT and MK (84%, 56%, 69%: p<0.001). Panton-Valentine leukocidin genes were found only in AT, HU, MK MSSA and MK MRSA in 2.3%, 4%, 1.5% (p=0.53) and 1% (p=0.38), respectively. The 3-gene combination pattern comprising of hla, hlg and hld genes showed increased prevalence among AT MSSA compared to HU (27%, 11%: p<0.001). The 4-gene pattern composed of hla, hlg, hlgv and hld genes was significantly characteristic for HU MRSA in contrast to AT and MK MRSA (56%, 12.5%, 27%: p<0.001). Frequency of certain cytotoxin genes and combinations differed significantly in Staphylococcus aureus strains according to geographical origin and methicillin-resistance.

blaNDM-1 Carriage on IncR Plasmid in Enterobacteriaceae Strains.

Four NDM-1-producing Enterobacteriaceae strains (three Klebsiella pneumoniae and one Citrobacter koseri) were isolated between 2009 and 2011 through a nationwide surveillance for carbapenem-resistant Enterobacteriaceae in Croatia to study the molecular genetic background of blaNDM and the responsible plasmid types. Phenotypically, the clinical strains proved to be multidrug resistant. All strains remained susceptible to tigecycline and colistin. The clinical strains harbored variable antibiotic resistance determinants, notably, blaNDM-1, blaTEM-1, blaSHV-1, blaSHV-12, blaOXA-1, blaOXA-9, blaCTX-M-15, blaCMY-4, qnrB1, and aac(6')Ib-cr in different combinations. Two K. pneumoniae belonged to sequence type ST15 and one strain to ST16. As for the plasmid types, C. koseri and one of the ST15 K. pneumoniae carried IncR, and the second ST15 K. pneumoniae carried IncR and colE. The K. pneumoniae ST16 strain hosted A/C and colE plasmids. The blaNDM-1 gene was detected on conjugative high-molecular-weight plasmids, namely, A/C and IncR types. It is noteworthy that this is the first description of K. pneumoniae ST16 expressing NDM-1 in Europe. Remarkably, our study underscores the importance of the IncR plasmid as a reservoir of multidrug resistance. To the best of our knowledge, the IncR plasmid carrying blaNDM-1 in C. koseri is reported for the first time.

KPC-3 carbapenemase harbored in FIIk plasmid from Klebsiella pneumoniae ST512 and Escherichia coli ST43 in the same patient.

Five carbapenem-resistant strains (three Klebsiella pneumoniae, one Escherichia coli, and one Enterobacter aerogenes) were isolated between 2009 and 2012 at the Verona University Hospital, Italy, during an epidemiological analysis of antibiotic resistance determinants and plasmid profiles in Enterobacteriaceae. Two out of the five strains, K. pneumoniae E530 and E. coli E558, were cultured from bile and abdominal drainage, respectively, of a single patient. The strains were resistant to beta-lactams and fluoroquinolones, and susceptible to tigecycline and colistin. All the strains harboured bla(KPC-3), bla(TEM-1), and bla(OXA-9), and the three K. pneumoniae additionally carried blaSHV-11 and aac(6')Ib. The bla(KPC-3) was inserted in transposon Tn4401a. All the strains hosted an FIIk-type plasmid, and the three K. pneumoniae coharboured an colE-type plasmid. Transconjugants, besides bla(KPC-3), harboured bla(TEM-1) and bla(OXA-9) genes on FIIk-type plasmid. K. pneumoniae E301 was ST258, while strain E530 and C525 belonged to the ST512, and E. coli E558 was ST43. To our best knowledge, this is the first report that strongly supports the transmission of bla(KPC-3) from ST512 K. pneumoniae to E. coli ST43 in a single patient, a phenomenon of both clinical and microbiological importance.

Identification of blaLAP-2 and qnrS1 genes in the internationally successful Klebsiella pneumoniae ST147 clone.

We investigated the presence of ß-lactamase genes (bla) in 26 strains of Enterobacteriaceae already found positive for the qnrS1 gene, a plasmid-mediated quinolone resistance determinant. Three strains of K. pneumoniae, isolated in the period 2008-2009 at the University Hospital in Verona, were positive for LAP-2, a narrow-spectrum ß-lactamase. These strains, namely VRB586, VRE185 and VRE196, were cultured from urine, bile and peritoneal drainage, respectively, of different patients from different units. The bla(LAP-2) and qnrS1 resistance determinant genes were separated by ISEcl2 and were located on a 97 kb conjugable and untypable plasmid, which could be transferred to a recipient strain, E. coli J53. The fluoroquinolone and ceftazidime MICs increased 1-2-fold in the transconjugant cells. The three K. pneumoniae strains were found to be clonal by PFGE and were identified as belonging to ST147, an internationally successful clone, by MLST. The plasmid sequence, including ISEcl2 and qnrS1 genes, of K. pneumoniae ST147 was found to be highly similar to previously detected qnrS1-harbouring plasmids, suggesting the plasmid has a stable genetic structure and that these resistance determinants have a common source. To the best of our knowledge, this is the first report of the internationally successful K. pneumoniae ST147 strain carrying bla(LAP-2) and qnrS1 genes and is the first case of LAP ß-lactamase in Italy.

Role of direct bioautographic method for detection of antistaphylococcal activity of essential oils.

The aim of the present study was the chemical characterization of some traditionally used and therapeutically relevant essential oils (thyme, eucalyptus, cinnamon bark, clove, and tea tree) and the optimized microbiological investigation of the effect of these oils on clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA). The chemical composition of the oils was analyzed by TLC, and controlled by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The antibacterial effect was investigated using a TLC-bioautographic method. Antibacterial activity of thyme, clove and cinnamon oils, as well as their main components (thymol, carvacrol, eugenol, and cinnamic aldehyde) was observed against all the bacterial strains used in this study. The essential oils of eucalyptus and tea tree showed weak activity in the bioautographic system. On the whole, the antibacterial activity of the essential oils could be related to their most abundant components, but the effect of the minor components should also be taken into consideration. Direct bioautography is more cost-effective and better in comparison with traditional microbiological laboratory methods (e.g. disc-diffusion, agar-plate technique).

Design, synthesis and determination of antifungal activity of 5(6)-substituted benzotriazoles.

In an effort to find inhibitors that are effective against both Candida and Aspergillus spp., a series of 5(6)-(un)substituted benzotriazole analogs, represented by compounds 3a-3h and 3b'-3f', were prepared using a crystalline oxirane intermediate 1 previously synthesized in our laboratory. All the compounds were evaluated for inhibitory activity against various species of Candida and Aspergillus. Compounds 3b' (5,6-dimethylbenzotriazol-2-yl derivative), 3d (5-chlorobenzotriazol-1-yl derivative) and 3e' (6-methylbenzotriazol-1-yl derivative) exhibited potent antifungal activity, with the MICs for Candida spp. and Aspergillus niger, ranging from 1.6 microg/mL to 25 microg/mL and 12.5 microg/mL to 25 microg/mL, respectively. The present work describes the design, synthesis, regioisomer characterization (through COSY and NOESY 2D-NMR spectroscopy and single molecule X-ray crystallography), antifungal evaluation, molecular docking, and structure-activity relationships of the various 5(6)-(un)substituted benzotriazole analogs.

Clinical microbiology of early-onset and late-onset neonatal sepsis, particularly among preterm babies.

Prematurity has got special challenge for clinicians and also other medical staff, such as microbiologists. Immature host defense mechanisms support early-onset sepsis, which can be very serious with very high mortality. While the past decade has been marked by a significant decline in early-onset group B streptococcal (GBS) sepsis in both term and preterm neonates, the overall incidence of early-onset sepsis has not decreased in many centers, and several studies have found an increase in sepsis due to gram-negative organisms. With increasing survival of these more fastidious preterm infants, late-onset sepsis or specially nosocomial bloodstream infection (BSI) will continue to be a challenging complication that affects other morbidities, length of hospitalization, cost of care, and mortality rates. Especially the very low birthweight (VLBW) infants sensitive to serious systemic infection during their initial hospital stay. Sepsis caused by multiresistant organisms and Candida spp. are also increasing in incidence, has become the most common cause of death among preterm infants. This review focuses on the clinical microbiology of neonatal sepsis, particularly among preterm babies, summarizing the most frequent bacterial and fungal organisms causing perinatally acquired and also nosocomial sepsis.