Marine Metabolomics: a Method for Nontargeted Measurement of Metabolites in Seawater by Gas Chromatography-Mass Spectrometry.

Microbial communities exchange molecules with their environment, which plays a major role in regulating global biogeochemical cycles and climate. While extracellular metabolites are commonly measured in terrestrial and limnic ecosystems, the presence of salt in marine habitats limits the nontargeted analyses of the ocean exometabolome using mass spectrometry (MS). Current methods require salt removal prior to sample measurements, which can alter the molecular composition of the metabolome and limit the types of compounds detected by MS.

Drying Enhances Signal Intensities for Global GC⁻MS Metabolomics.

We report here that a straightforward change of the standard derivatization procedure for GC⁻MS metabolomics is leading to a strong increase in metabolite signal intensity. Drying samples between methoxymation and trimethylsilylation significantly increased signals by two- to tenfold in extracts of yeast cells, plant and animal tissue, and human urine. This easy step reduces the cost of sample material and the need for expensive new hardware.

Surveillance of human rotaviruses in 2007-2011, Hungary: exploring the genetic relatedness between vaccine and field strains.

Background: The availability of rotavirus vaccines has resulted in an intensification of post vaccine strain surveillance efforts worldwide to gain information on the impact of vaccines on prevalence of circulating rotavirus strains.

Objectives: In this study, the distribution of human rotavirus G and P types in Hungary is reported. In addition, the VP4 and VP7 genes of G1P[8] strains were sequenced to monitor if vaccine-derived strains were introduced and/or some strains/lineages were selected against.

Phylogenetic analysis of a nosocomial transmission of hepatitis B virus at a paediatric haematology ward.

A nosocomial Hepatitis B virus (HBV) outbreak at a paediatric onco-haematology unit was investigated using molecular biological methods to determine the origin of the infections. The National Reference Laboratory of Hepatitis Viruses received seven HBsAg positive sera from patients and one from the brother of a patient. A fragment of the preS1/preS2/S genes from all samples was amplified, the PCR products were sequenced and a rooted phylogenetic tree was constructed.

Emergence of a colistin-resistant KPC-2-producing Klebsiella pneumoniae ST258 clone in Hungary.

Nine Klebsiella pneumoniae isolates showing non-susceptibility to carbapenems were collected from three centres in the north-eastern region of Hungary. The minimum inhibitory concentrations (MICs) of antibiotics were determined by Etest. The putative production of a carbapenemase was tested by the modified Hodge test.