ABSTRACT
AIM: Molecular analysis of Streptococcus pyogenes types emm1 and emm12 genomes on the presence of genes belonging to prophage DNA. MATERIALS AND METHODS: Thirty-one strains of S. pyogenes type emm1 and 22 strains of S. pyogenes type emm12 were objects of the study. Polymerase chain reaction with special primers for detection of 24 phage genes was used in the study. RESULTS: Prevalence of phage genes in strains of different emm types was assessed. The following phage genes were most frequently detected: speA, speC, ssa genes for emm1 type and speC and speH for emm12 type. On the basis of the study, 19 different profiles of phage genes were identified. CONCLUSION: The study allowed to identify not only differences but also similarities between strains of emm1 and emm12 types on prophage gene repertoire in bacterial genome. Presence of similarities allows to assume the possibility of circulation in the studied region similar or identical bacteriophages between streptococci group A (SGA) strains of different emm types.
Subject(s)
Genes, Viral , Prophages/genetics , Streptococcus Phages/genetics , Streptococcus pyogenes/genetics , Streptococcus pyogenes/virology , ChinaABSTRACT
Down syndrome (DS) results from triplication of the whole or distal part of human chromosome 21. Persons with DS suffer from deficits in learning and memory and cognitive functions in general, and, starting from early development, their brains show dendritic and spine structural alterations and cell loss. These defects concern many cortical brain regions as well as the hippocampus, which is known to play a critical role in memory and cognition. Most of these abnormalities are reproduced in the mouse model Ts65Dn, which is partially trisomic for the mouse chromosome 16 that is homologous to a portion of human chromosome 21. Thus, Ts65Dn is widely utilized as an animal model of DS. To better understand the molecular defects underlying the cognitive and particularly the memory impairments of DS, we investigated whether the expression of several molecules known to play critical roles in long-term synaptic plasticity and long-term memory in a variety of species is dysregulated in either the neonatal brain or adult hippocampus of Ts65Dn mice. We found abnormal expression of the synaptic proteins synaptophysin, microtubule-associated protein 2 (MAP2) and cyclin-dependent kinase 5 (CDK5) and of the neurotrophin-3 (NT-3). Both the neonatal brain and adult hippocampus revealed significant abnormalities. These results suggest that a dysregulation in the expression of neurotrophins as well as proteins involved in synaptic development and plasticity may play a potential role in the neural pathology of DS in humans.
Subject(s)
Brain/metabolism , Down Syndrome/metabolism , Neurotrophin 3/metabolism , Synapses/metabolism , Synaptophysin/metabolism , Animals , Animals, Genetically Modified , Animals, Newborn , Brain/pathology , Brain/physiopathology , Cyclin-Dependent Kinase 5/genetics , Cyclin-Dependent Kinase 5/metabolism , Disease Models, Animal , Down Syndrome/genetics , Down Syndrome/physiopathology , Female , Hippocampus/metabolism , Hippocampus/pathology , Hippocampus/physiopathology , Male , Memory Disorders/genetics , Memory Disorders/metabolism , Memory Disorders/physiopathology , Mice , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Neuronal Plasticity/genetics , Neurotrophin 3/genetics , Synapses/genetics , Synaptophysin/geneticsABSTRACT
A high-throughput liquid chromatography-tandem mass spectrometry method is described for the determination of multiple compounds in dog and rat plasma. After acetonitrile precipitation of plasma proteins, the analytes are pre-concentrated and back-flushed on a reversed-phase column for separation using a switching valve. The analytes are ionized using TurboIon Spray in a positive mode, and detected by multiple reaction monitoring. Automatic tuning software is used for fast method development. The data processing is greatly speeded up by using a powerful quantitation software package. Chromatography of multiple compounds takes only 4 min. The linear calibration curve ranges from 0.5 to 1000 ng/ml. This method was successfully used in the analysis of multi-compounds for preclinical pharmacokinetic studies.
