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Aims This study aimed to investigate the presence of beta-lactams resistance genes and the clonal relationship of clinical isolates of Enterobacterales obtained from patients with and without COVID-19, in a hospital in northeastern Brazil. Methods and results The study analyzed 45 carbapenem-resistant clinical isolates using enterobacterial repetitive intergenic consensus (ERIC-PCR), PCR, and amplicon sequencing to detect resistance genes (bla KPC, bla GES, bla NDM, bla VIM, and bla IMP). The main species were Klebsiella pneumoniae, Serratia marcescens , and Proteus mirabilis. Detected genes included bla NDM (46.66%), bla KPC (35.55%), and both (17.79%). ERIC-PCR showed multiclonal dissemination and high genetic variability. The main resistance gene was bla NDM, including bla NDM-5 and bla NDM-7. Conclusions The presence of Enterobacterales carrying bla KPC and bla NDM in this study, particularly K. pneumoniae , in infections and colonizations of patients with COVID-19 and non-COVID-19, highlights genetic variability and resistance to carbapenems observed in multiple species of this order. [ABSTRACT FROM AUTHOR]

Aims To investigate the genetic profile and characterize antimicrobial resistance, including the main β-lactam antibiotic resistance genes, in Acinetobacterbaumannii isolates from a tertiary hospital in Recife-PE, Brazil, in the post-COVID-19 pandemic period. Methods and Results Acinetobacter baumannii isolates were collected between 2023 and 2024 from diverse clinical samples. Antimicrobial resistance testing followed standardized protocols, with β-lactamase-encoding genes detected via PCR and sequencing. Investigation into ISAba1 upstream of bla OXA-carbapenemase and bla ADC genes was also conducted. Genetic diversity was assessed through ERIC-PCR. Among the 78 A. baumannii , widespread resistance to multiple antimicrobials was evident. Various acquired β-lactamase-encoding genes (bla OXA-23,-24,-58,-143, bla VIM, and bla NDM) were detected. Furthermore, this is the first report of bla VIM-2 in A. baumannii isolates harboring either the bla OXA-23-like or the bla OXA-143 gene in Brazil. Molecular typing revealed a high genetic heterogeneity among the isolates, and multi-clonal dissemination. Conclusion The accumulation of genetic resistance determinants underscores the necessity for stringent infection control measures and robust antimicrobial stewardship programs to curb multidrug-resistant strains. [ABSTRACT FROM AUTHOR]

Aims Investigated and compared the occurrence of virulence genes fimH, mrkD, irp2, entB, cps, rmpA , and wabG , resistance genes bla KPC and bla NDM, and the genetic variability and clonal relationship of 29 Klebsiella pneumoniae clinical isolates of patients with and without COVID-19, from a hospital in Brazil. Methods and results All isolates were resistant to beta-lactams. The genes were investigated by PCR, and for molecular typing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and MLST were used. The detection of bla NDM was greater (n  = 23) when compared to that of bla KPC (n  = 14). The virulence genes that most occurred were fimH, entB, cps , and wabG , which are responsible for adhesins, siderophore enterobactin, capsule, and lipopolysaccharides, respectively. Among the isolates, 21 distinct genetic profiles were found by ERIC-PCR, with multiclonal dissemination. Four isolates belonged to the ST11 clone. Conclusions The occurrence of the ST11 is worrying as it is a high-risk clone involved in the dissemination of virulent strains throughout the world. [ABSTRACT FROM AUTHOR]

This study aimed to co-encapsulate ceftazidime and tobramycin in zein nanoparticles coated with chitosan and to characterize and evaluate the antibacterial and antibiofilm activity against antibiotic-resistant Pseudomonas aeruginosa and Klebsiella pneumoniae. Zein nanoparticles, synthesized using the nanoprecipitation method, were characterized by their particle size (Ø), polydispersity index (PDI), zeta potential (ζ), pH, and encapsulation efficiency (%EE). The chitosan coating provided stability, and physicochemical analyses revealed chemical interactions, efficient drug encapsulation, and thermal stability. The release kinetics demonstrated controlled release in simulated gastric and intestinal pH. The antibacterial activity, assessed by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), indicated effectiveness against both pathogens. Antibiofilm assays, conducted using the crystal violet method, demonstrated the inhibition and eradication of biofilms. The chitosan-coated zein nanoparticles with CAZ and/or TOB exhibited Ø (315–335 nm), PDI (<0.2), ζ (+40 to +50 mV), pH (5), and %EE (>55%). Notably, the co-encapsulation formulation (CAZ–TOB–ZNP–CH) showed enhanced antibacterial and antibiofilm activities compared to the individual formulations. These findings suggest that the developed nanoparticles present a promising alternative for treating respiratory and intestinal infections caused by antibiotic-resistant and biofilm-producing P. aeruginosa and K. pneumoniae. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has engendered significant scientific efforts in the understanding of its infectious agent SARS-CoV-2 and of its associated symptoms. A peculiar characteristic of this virus lies in its ability to challenge our senses, as its infection can lead to anosmia and ageusia. While ocular symptoms, such as conjunctivitis, optic neuritis or dry eyes, are also reported after viral infection, they have lower frequencies and severities, and their functional development is still elusive. Here, using combined technical approaches based on histological and gene profiling methods, we characterized the expression of SARS-CoV-2 binding sites (Ace2/Tmprss2) in the mouse eye. We found that ACE2 was ectopically expressed in subtissular ocular regions, such as in the optic nerve and in the Harderian/intraorbital lacrimal glands. Moreover, we observed an important variation of Ace2/Tmprss2 expression that is not only dependent on the age and sex of the animal, but also highly heterogenous between individuals. Our results thus give new insight into the expression of SARS-CoV-2 binding sites in the mouse eye and propose an interpretation of the human ocular-associated symptoms linked to SARS-CoV-2. [ABSTRACT FROM AUTHOR]

OBJETIVOS: investigar a prevalência Streptococus pyogenes em secreção de orofaringe de escolares procedentes de duas escolas públicas da cidade Recife. MÉTODOS: estudo epidemiológico e clínico-microbiológico descritivo no qual foram examinados 753 escolares. A cultura bacteriana da secreção orofaringeana foi realizada em ágar-sangue de carneiro 5% e as cepas SBGA identificadas através dos testes de bacitracina, Pyr e aglutinação em látex. RESULTADOS: a faixa etária dos 753 escolares analisados variou de cinco a 19 anos, sendo 54,3% do sexo masculino e 45,7% do sexo feminino. Seis eram portadores assintomáticos de SBGA e foram submetidos ao tratamento com penicilina. Após o tratamento, realizou-se a dosagem da antiestreptolisina o (ASLO), cujos títulos séricos foram inferiores a 200UT. CONCLUSÕES: uma prevalência de SBGA de 0,8% foi estimada em portadores assintomáticos, considerada baixa, quando comparado a outros resultados em estudos semelhantes. Os autores sugerem a realização de outros estudos para estimar a prevalência de SBGA em crianças com faringite e sua relação com a febre reumática aguda.

To characterize phenotypically and genotypically an isolate of multidrug-resistant (MDR) K. pneumoniae from a patient with septicemia in a hospital in Recife-PE, Brazil, resistance and virulence genes were investigated using PCR and sequencing the amplicons, and the plasmid DNA was also sequenced. The K74-A3 isolate was resistant to all β-lactams, including carbapenems, as well as to aminoglycosides and quinolones. By conducting a PCR analysis and sequencing, the variants blaNDM-7 associated with blaKPC-2 and the cps, wabG, fim-H, mrkD and entB virulence genes were identified. The analysis of plasmid revealed the presence of blaCTX-M15, aac(3)-IVa, aph(3′)-Ia, aph(4)-Ia, aac(6′)ib-cr, mph(A) and catB3, and also the plasmids IncX3, IncFIB, IncQ1, ColRNAI and ColpVC. To our knowledge, this is the first report of the blaNDM-7 gene in Recife-PE and we suggest that this variant is located in IncX3. These results alert us to the risk of spreading an isolate with a vast genetic arsenal of resistance, in addition to which several plasmids are present that favor the horizontal transfer of these genes. [ABSTRACT FROM AUTHOR]

Magnetoelastic resonant platforms are gaining attention in different sensing applications due mainly to their wireless detecting capacity. In that way, the improvement of the main parameters of those devices turns out to be essential in the development of advanced functional magnetoelastic resonators. In our attempt to improve such systems, we concluded that modified geometries of the resonant platforms can be a good alternative to achieve higher mass sensitivities. In this work, a novel high sensitive rhombus shaped magnetoelastic resonant platform design has been proposed. The obtained mass sensitivities have been both experimentally and theoretically compared with the classical rectangular sensors case. The results of these novel sensor geometry performance show an increase on the resonance frequency value by a factor of 1.53 with respect to the traditional rectangular one and, as a first consequence, an improvement of more than a 60 % in the mass sensitivity value. Besides, a multiple detection system based on a combination of both magnetoelastic platform geometries has been developed. The obtained results are very promising in the goal of achieving improved and novel multiple detection systems. [ABSTRACT FROM AUTHOR]

Acute CrVI water pollution due to anthropogenic activities is an increasing worldwide concern. The high toxicity and mobility of CrVI makes it necessary to develop dual adsorbent/ion‐reductive materials that are able to capture CrVI and transform it efficiently into the less hazardous CrIII. An accurate description of chromium speciation at the adsorbent/ion‐reductive matrix is key to assessing whether CrVI is completely reduced to CrIII, or if its incomplete transformation has led to the stabilization of highly reactive, transient CrV species within the material. With this goal in mind, a dual ultraviolet–visible and electron paramagnetic spectroscopy approach has been applied to determine the chromium speciation within zirconium‐based metal–organic frameworks (MOFs). Our findings point out that the generation of defects at Zr‐MOFs boosts CrVI adsorption, whilst the presence of reductive groups on the organic linkers play a key role in stabilizing it as isolated and/or clustered CrIII ions. [ABSTRACT FROM AUTHOR]

The monitoring of different harmful gases such as volatile organic compounds (VOCs) is essential to ensure the air quality and population security. Therefore, the development of rapid, cheap and accurate sensing devices is a key to enable continuous monitoring of the air quality. On this matter, magnetoelastic sensors, particularly the rhombus-shaped ones, have become an interesting alternative to the current sensing systems because, besides exhibiting a fast response, they present a wireless sensing capacity. Moreover, the addition of metal–organic frameworks (MOFs) as highly porous active layers to different sensing devices endows them with the desired adsorption capacity and selectivity to detect VOCs. Therefore, in this work, we explore the performance of a highly sensitive rhombic magnetoelastic Metglas 2826 MB resonator functionalized with a high-toluene adsorption capacity MOF layer (i.e. UiO66-NH2) for its wireless detection. Our findings confirm the feasibility of the Metglas/MOF system for fast and reversible toluene detection, being key the control of the active layer mass to improve its sensitivity. From the toluene sensing experiments, a maximum sensitivity of 0.27 Hz ppm−1 was determined. Finally, the sensor selectivity has been evaluated through the analysis of the sensor response to different atmospheres (water, acetone, ethanol and toluene) and it was observed that the sensor presents an enhanced selectivity towards toluene. Given the structural diversity and chemical tunability of MOF materials, their use as active sorbent layers in resonator systems together with the possibility to further optimize the resonator geometry to improve the sensitivity and the MOF structure to gain more selectivity, opens up the possibility for the facile and straightforward designing of future wireless sensors for any kind of environmentally hazardous substance. [ABSTRACT FROM AUTHOR]

This work aimed to investigate the chemical composition, antimicrobial, antinociceptive, acute toxicity and antioxidant activity of the essential oil of Algrizea minor (EOAm). The essential oil presented as the major constituents β-Pinene (56.99%), α-Pinene (16.57%), Germacrene D (4.67%), Bicyclogermacrene (4.66%), (E)-Caryophyllene (3.76%) and Limonene (1.71%). It was verified that the essential oil did not show acute toxicity in the maximum dose of 5,000 mg/kg. In the evaluation of the antinociceptive activity it was verified that the essential oil reduced in 65.84% the number of writhing in the mice, reducing the pain in 59.17%, and the mechanism of action in pain reduction was opioid, similar to morphine. The essential oil also presented significant antimicrobial against Gram positive and Gram-negative bacteria and fungi, and the antioxidant activity was relevant. Therefore, these results demonstrate the great potential for the future development of pharmaceutical products with the essential oil of Algrizea minor (EOAm). [ABSTRACT FROM AUTHOR]

Novel piezo-ionic/magnetostrictive bi-layer composites for new energy generation devices are presented. These structures, fabricated with Metglas® 2826MB ferromagnetic alloys and ionic liquid based PVDF-HFP polymer composites, show an induced electric response as a consequence of the coupling between the magnetostrictive properties of the Metglas® 2826MB and the piezo-ionic ones of the ionic liquid based PVDF-HFP polymer composites. These flexible, simple and low cost structures do not need to be polarized to exhibit an electric response, and show an increased induced voltage as the percentage of the ionic liquid in the PVDF-HFP matrix does. This response is a consequence of the asymmetric deformation caused by the magnetostrictive material on the piezo-ionic composite, which induces a non-uniform distribution of the cations and anions in the polymer matrix. The laminates present a maximum response under the application of a low magnetic fields of 9 Oe, and a normalized magneto-ionic coefficient values up to 550 mV cm−1.Oe for the structure with an ionic liquid content of 30 %. These values are even higher than others obtained with piezoelectric materials based ME composites. The simple fabrication process and potentiality of these new piezo-ionic/magnetostrictive laminates contributes to broaden and improve the state of the art of the energy generation systems. [ABSTRACT FROM AUTHOR]

Abstract The increase in urbanization and industrialization has contributed to the contamination of different environments by means of xenobiotic compounds, such as heavy metals, causing changes in microbial communities. Among these metals, the Mercury (Hg2+) is one the most prevalent toxic metals for the environment The present study aimed to evaluate the effect of mercury on the formation of biofilm by environmental (collected from urban stream water) and clinical isolates of Klebsiella pneumoniae. In addition, antibiotic resistance, virulence factors, and genetic diversity were investigated. Taxonomic identity of eight isolates (one reference, two clinical, and five environmental isolates) was performed by MALDI-TOF-MS, while the antibiotic susceptibility profile was assessed by the disc diffusion method. The ability to form biofilms was evaluated by culture on Congo red agar and by crystal violet staining. Biofilm structure was analyzed by scanning electron microscopy. The hydrophobicity profile and the presence of the virulence genes cps , fimH , and mrkD was investigated. The presence of merA and its relationship with antimicrobial resistance were also assessed. The identity of all isolates was confirmed by MALDI-TOF-MS, and different profiles of resistance to mercury and antibiotics as well as of biofilm formation were identified for the clinical and environmental isolates. All isolates were hydrophilic and positive for the virulence genes cps , fimH , and mrkD ; only the clinical isolate K36-A2 was positive for merA. The diversity of the isolates was confirmed by ERIC-PCR, which revealed high heterogeneity among the isolates. In conclusion, the data demonstrate that the investigated isolates present different responses to exposure to Hg2+ and correspond to distinct populations of K. pneumoniae disseminated in the investigated environment. The data obtained in this work will aid in understanding the mechanisms of survival of this pathogen under adverse conditions. Highlights • In vitro effect of Hg2+ was observed on the formation of biofilms in K. pneumoniae. • Hg2+ can act as a stress factor for most isolates of K. pneumoniae. • Different populations of K. pneumoniae were observed in the analyzed ecosystem. • The work discusses mechanisms of survival of this pathogen under adverse conditions. [ABSTRACT FROM AUTHOR]

We report the fabrication by melt spinning, the magnetic and magnetoelastic characterization and corrosion behaviour study (by potentiodynamic methods) of an Fe-based, Fe-Ni-Cr-Si-B metallic glass to be used as resonant platform for biological and chemical detection purposes. The same study has been performed in Fe-Co-Si-B (with excellent magnetoelastic properties) and Fe-Ni-B (with good corrosion properties due to the substitution of Co by Ni) composition amorphous alloys. The well-known, commercial metallic glass with high corrosion resistance Metglas 2826MB®(Fe40Ni38Mo4B18), widely used for such biological and chemical detection purposes, has been also fully characterized and used as reference. For our Fe-Ni-Cr-Si-B alloy, we have measured values of magnetization (1.22 T), magnetostriction (11.5 ppm) and ΔE effect (6.8 %) values, as well as corrosion potential (-0.25 V), current density (2.54 A/m2), and polarization resistance (56.22 Ω.cm2) that make this composition very promising for the desired biosensing applications. The obtained parameters from our exhaustive characterization are compared with the values obtained for the other different composition metallic glasses and discussed in terms of Ni and Cr content. [ABSTRACT FROM AUTHOR]

The main parameters of magnetoelastic resonators in the detection of chemical (i.e., salts, gases, etc.) or biological (i.e., bacteria, phages, etc.) agents are the sensitivity S (or external agent change magnitude per Hz change in the resonance frequency) and the quality factor Q of the resonance. We present an extensive study on the experimental determination of the Q factor in such magnetoelastic resonant platforms, using three different strategies: (a) analyzing the real and imaginary components of the susceptibility at resonance; (b) numerical fitting of the modulus of the susceptibility; (c) using an exact mathematical expression for the real part of the susceptibility. Q values obtained by the three methods are analyzed and discussed, aiming to establish the most adequate one to accurately determine the quality factor of the magnetoelastic resonance. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the ultrastructural effects caused by β-lactam antibiotics in Klebsiella pneumoniae isolates. Three K. pneumoniae clinical isolates were selected for the study with resistance profiles for third-generation cephalosporins, aztreonam, and/or imipenem and with different resistance genes for extended-spectrum β-lactamases (ESBL) or Klebsiella pneumoniae carbapenemase (KPC). Two K. pneumoniae isolates obtained from the microbiota, which were both resistant to amoxicillin and ampicillin, were also analyzed. In accordance with the susceptibility profile, the clinical isolates were subjected to subminimum inhibitory concentrations (sub-MICs) of cefotaxime, ceftazidime, aztreonam, and imipenem and the isolates from the microbiota to ampicillin and amoxicillin, for analysis by means of scanning and transmission electron microscopy. The K. pneumoniae isolates showed different morphological and ultrastructural changes after subjection to β-lactams tested at different concentrations, such as cell filamentation, loss of cytoplasmic material, and deformation of dividing septa. Our results demonstrate that K. pneumoniae isolates harboring different genes that encode for β-lactamases show cell alterations when subjected to different β-lactam antibiotics, thus suggesting that they possess residual activity in vitro, despite the phenotypic resistance presented in the isolates analyzed. [ABSTRACT FROM AUTHOR]

Eighty-five isolates of Klebsiella pneumoniae and Enterobacter spp., originating from hospital- and community-acquired infections and from oropharyngeal and faecal microbiota from patients in Recife-PE, Brazil, were analyzed regarding the presence of irp2 gene. This is a Yersinia typical gene involved in the synthesis of siderophore yersiniabactin. DNA sequencing confirmed the identity of irp2 gene in five K. pneumoniae , five Enterobacter aerogenes and one Enterobacter amnigenus isolates. To our knowledge in the current literature, this is the first report of the irp2 gene in E. amnigenus , a species considered an unusual human pathogen, and in K. pneumoniae and E. aerogenes isolates from the normal microbiota and from community infections, respectively. Additionally, the analyses of nucleotide and amino acid sequences suggest the irp2 genes derived from isolates used in this study are more closely related to that of Yersinia pestis P.CE882 than to that of Yersinia enterocolitica 8081. These data demonstrated that K. pneumoniae and Enterobacter spp. from normal microbiota and from community- and hospital-acquired infections possess virulence factors important for the establishment of extra-intestinal infections. [ABSTRACT FROM AUTHOR]

A systematic study for the production of porous poly(vinylidene fluoride-trifluoroethylene), P(VDF-TrFE), films using solvent evaporation and nonsolvent induced phase separation techniques is presented. Processing parameters such as copolymer volume fraction, solvent, preset exposure time to air before immersion, and nonsolvent and temperature of the coagulation bath were varied and the corresponding sample morphology, hydrophobicity, thermal, and mechanical properties were determined. Film morphologies including homogeneous pore distributions, micropores, microvoids, spherulites, and nonporous films were obtained. The morphology variations strongly influence sample hydrophobicity and mechanical properties. All samples crystallized in the electroactive β-phase with a degree of crystallinity around 30%. [ABSTRACT FROM PUBLISHER]

The periodic assessment of claddings adhesion during the facade life cycle becomes an important preventive in-service issue. This paper discusses the pull-off test, anin-situdiagnosis technique, which characterizes the in-service performance of ceramic tile claddings, by measuring adherence resistance to tension. Adherence is one of the main required properties of external coating, not only for aesthetical reasons but also for safety purposes. Throughout this research, an experimental campaign is performed in laboratory andin-situ, analyzing the variability of the pull-off testing technique.In-situtests have been undertaken in existing construction sites and test walls. The laboratory results were compared to thein-situones. Standards requirements were evaluated and different failure modes were verified. In this work the impact of several parameters is analyzed such as the use of metallic discs with different thickness levels, geometries, and dimensions; the location of the testing at different heights; and the use of different dynamometer equipment. The main conclusion of this work is in order to reduce the uncertainty of the in-service diagnosis used for decision process of facade interventions, the previous parameters should be taking into account despite pull-off being a standardized technique. [ABSTRACT FROM PUBLISHER]

Simple Summary: The mouse olfactory system is essential for danger detection with a critical role in the Grueneberg ganglion subsystem. This organ, which is localized at the tip of the nose, is implicated in the recognition of kairomones, or chemical cues released by predators which allow interspecies communication. These kairomones, which are present in the secretions of predators, will induce fear-related behaviours in mice. It is not yet known how the Grueneberg ganglion neurons can detect these molecules; however, three specific bitter taste receptors, known as TAS2Rs, that are present in the Grueneberg ganglion play a role in this detection. Here, using in vitro, ex vivo and in vivo experimental approaches, we identified two novel and potent sources of kairomones that are recognized by the mouse Grueneberg ganglion neurons, namely the biological secretions from the raccoon (Procyon lotor) and the skunk (Mephitis mephitis). In the wild, mice have developed survival strategies to detect volatile cues that warn them of potential danger. Specific olfactory neurons found in the Grueneberg ganglion olfactory subsystem can detect alarm pheromones emitted by stressed conspecifics, as well as kairomones involuntarily released by their predators. These volatile chemical cues allow intra- and interspecies communication of danger, respectively. Alarm pheromones, kairomones and bitter taste ligands share a common chemical motif containing sulfur or nitrogen. Interestingly, three specific bitter taste receptors (TAS2Rs) have been found in the Grueneberg ganglion neurons that are implicated in danger signalling pathways. We have recently developed a TAS2R–expressing heterologous system that mimics the Grueneberg ganglion neuron responses after kairomone stimulation. Here, we demonstrated by in vitro, ex vivo and in vivo experiments that the biological secretions from the raccoon (Procyon lotor) and the skunk (Mephitis mephitis) were acting as potent sources of kairomones. They activated the Grueneberg ganglion neurons and induced fear-related behaviours in mice. Identification of new sources of semiochemicals is a first step towards an understanding of the interspecies danger communication that takes place in the Grueneberg ganglion. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the prevalence of the bla gene in Klebsiella pneumoniae isolates from hospital and community infections and from the normal microbiota of healthy individuals in Recife, PE, Brazil. Fifty-two K. pneumoniae isolates were analyzed regarding the presence of the bla gene, using PCR, and eight isolates were analyzed by DNA sequencing. This gene was detected in 16 isolates from hospital infections, four from community infections, and nine from the normal microbiota. This was the first study to find the bla gene in K. pneumoniae isolates from the normal microbiota. Through DNA sequencing of eight K. pneumoniae isolates from hospital and community infections, with a resistance phenotype indicative of extended-spectrum β-lactamase production, a new SHV variant named SHV-122 was found. We also detected the presence of bla, bla, bla, and bla. The results show that in Recife, Brazil, K. pneumoniae isolates that presented resistance to oxyimino-β-lactams had high prevalence and diversity of the bla gene. We also conclude that there was a high presence of the bla gene among isolates from the normal microbiota of healthy individuals. [ABSTRACT FROM AUTHOR]

Summary: Thirty nosocomial isolates of Klebsiella pneumoniae, collected from three public hospitals in Recife, Brazil, between 1999 and 2000, were analysed in order to determine their epidemiological relatedness and genetic characteristics. The isolates were characterised by biotyping, antibiotyping, protein analysis, plasmid profile and random amplified polymorphic DNA (RAPD). The majority of the clinical isolates were resistant to multiple antibiotics, in particular to β-lactams, and 30% were found to be ESBLs producers. RAPD proved to be the most effective technique in discriminating unrelated K. pneumoniae isolates. It was confirmed by the highly genetic similarity found among related isolates from an hospital outbreak. We conclude that K. pneumoniae infections in Recife has been caused by a variety of bacterial genotypes. This is the first report that revealed the subtypes of K. pneumoniae in Brazil by plasmid analysis and RAPD. [Copyright &y& Elsevier]

We have performed a study of the magnetic, magnetoelastic, and corrosion resistance properties of seven different composition magnetoelastic-resonant platforms. For some applications, such as structural health monitoring, these materials must have not only good magnetomechanical properties, but also a high corrosion resistance. In the fabricated metallic glasses of composition Fe 73 − x Ni x Cr 5 Si 10 B 12 , the Fe/Ni ratio was varied (Fe + Ni = 73% at.) thus changing the magnetic and magnetoelastic properties. A small amount of chromium ( Cr 5) was added in order to achieve the desired good corrosion resistance. As expected, all the studied properties change with the composition of the samples. Alloys containing a higher amount of Ni than Fe do not show magnetic behavior at room temperature, while iron-rich alloys have demonstrated not only good magnetic properties, but also good magnetoelastic ones, with magnetoelastic coupling coefficient as high as 0.41 for x = 0 in the Fe 73 Ni 0 Cr 5 Si 10 B 12 (the sample containing only Fe but not Ni ). Concerning corrosion resistance, we have found a continuous degradation of these properties as the Ni content increases in the composition. Thus, the corrosion potential decreases monotonously from 46.74 mV for the x = 0 , composition Fe 73 Ni 0 Cr 5 Si 10 B 12 to −239.47 mV for the x = 73 , composition Fe 0 Ni 73 Cr 5 Si 10 B 12 . [ABSTRACT FROM AUTHOR]

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