ABSTRACT
Staphylococcus aureus, or methicillin-resistant S. aureus (MRSA), is a significant pathogen in both nosocomial and community infections. Community-associated MRSA (CA-MRSA) strains tend to be multi-drug resistant and to invade hospital settings. This study aimed to assess the antimicrobial resistance and molecular characteristicsof nasal S. aureus among newlyadmitted inpatients.In the present study, 66 S. aureus isolates, including 10 healthcare-associated MRSA (HA-MRSA), 8 CA-MRSA, and 48 methicillin-sensitive S. aureus (MSSA) strains, were found in the nasal cavities of 62 patients by screening 292 newlyadmitted patients. Antimicrobial resistance and molecular characteristics of these isolates, including spa-type, sequence type (ST) and SCCmec type, were investigated. All isolates were sensitive to linezolid, teicoplanin, and quinupristin/dalfopristin, but high levels of resistance to penicillin and erythromycin were detected. According to D-test and erm gene detection results, the cMLSB and iMLSB phenotypes were detected in 24 and 16 isolates, respectively. All 10 HA-MRSA strains displayed the cMLSB phenotypemediated by ermA or ermA/ermC, while the cMLSB CA-MRSA and MSSA strains carried the ermB gene. Molecular characterization revealedall 10 HA-MRSA strains were derived from the ST239-SCCmec III clone, and four out of eight CA-MRSA strains were t437-ST59-SCCmec V. The results suggest that patients play an indispensable role in transmitting epidemic CA-MRSA and HA-MRSA strains.
Subject(s)
Humans , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Drug Resistance, Multiple, Bacterial/genetics , Inpatients , Methicillin-Resistant Staphylococcus aureus/drug effects , Methyltransferases/genetics , Microbial Sensitivity Tests , Nasal Cavity/microbiology , Staphylococcal Infections/diagnosis , Staphylococcus aureus/drug effectsABSTRACT
SUMO (small ubiquitin-related modifier) is involved in the post-translational modifications of proteins,and this process is referred to as SUMOylation.SUMOylation plays an important role in the regulation of cellular activities such as strengthening the stability of the protein,nucleocytoplasmic transport,DNA repair,DNA replication,mitotic and meiotic chromosome behavior,et al.SUMOylation is a dynamic process and can be reversed by SUMO-specific proteases (SENP).Once the balance between SUMOylation and de-SUMOylation is broken,there will be an aberrant expression of SUMO or SENPs in cells to happen,which may lead to the tumor occturtrence.
ABSTRACT
Objective:To lay background for studying rejection mechanisms in xenotransplantation, class II DQA genes of swine leukocyte antigens (SLA) of three Chinese pig strains GXP, GZP and YNP were cloned and sequenced.Methods:RT-PCR was performed to proliferate SLA-DQA genes (GXPDQA, GZPDQA and YNPDQA),which were cloned into pGEM-T Easy vector for sequencing and analysis.Results:All three allelic sequences examined, are not identical to those reported, which allows the sequences receiving their accession numbers from GenBank as AY102473, AY102474 and AY102475, which encompass an open reading frame of 765, 768 and 768 nucleotides respectively.Conclusion:Three new alleles of SLA-DQA genes were obtained. Analysis of the amino acid sequences of swine, human and mouse DQA (or equivalent) also indicated that GXPDQA, GZPDQA and YNPDQA were more similar to human DQA than mouse H-2-A?, which might provide an understanding of how the immune system evolved.