There was poor or slight concordance in disclosure preferences between patients with cancer and their families. More patients than their families wanted to be informed completely, immediately, and directly by doctors. Farmer patients with cancer were less likely to prefer to be informed completely, immediately, and directly by doctors.
Recent studies demonstrated that NADPH oxidase 2 (NOX2) expression in myocardium after ischemia-reperfusion (IR) is significantly upregulated. However, the underlying mechanisms remain unknown. This study aims to determine if nuclear cardiac myosin light chain 2 (MYL2), a well-known regulatory subunit of myosin, functions as a transcription factor to promote NOX2 expression following myocardial IR in a phosphorylation-dependent manner. We examined the phosphorylation status of nuclear MYL2 (p-MYL2) in a rat model of myocardial IR (left main coronary artery subjected to 1 h ligation and 3 h reperfusion) injury, which showed IR injury and upregulated NOX2 expression as expected, accompanied by elevated H₂O₂ and nuclear p-MYL2 levels; these effects were attenuated by inhibition of myosin light chain kinase (MLCK). Next, we explored the functional relationship of nuclear p-MYL2 with NOX2 expression in H9c2 cell model of hypoxia-reoxygenation (HR) injury. In agreement with our in vivo findings, HR treatment increased apoptosis, NOX2 expression, nuclear p-MYL2 and H₂O₂ levels, and the increases were ameliorated by inhibition of MLCK or knockdown of MYL2. Finally, molecular biology techniques including co-immunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP), DNA pull-down and luciferase reporter gene assay were utilized to decipher the molecular mechanisms. We found that nuclear p-MYL2 binds to the consensus sequence AGCTCC in NOX2 gene promoter, interacts with RNA polymerase II and transcription factor IIB to form a transcription preinitiation complex, and thus activates NOX2 gene transcription. Our results demonstrate that nuclear MYL2 plays an important role in IR injury by transcriptionally upregulating NOX2 expression to enhance oxidative stress in a phosphorylation-dependent manner.
Acquisition of vancomycin resistance in Staphylococcus aureus is often accompanied by a reduction in virulence, but the mechanisms underlying this change remain unclear. The present study was undertaken to investigate this process in a clinical heterogeneous vancomycin-intermediate S. aureus (hVISA) strain, 10827; an hVISA reference strain, Mu3; and a VISA reference strain, Mu50, along with their respective series of vancomycin-induced resistant strains. In these strains, increasing MICs of vancomycin were associated with increased expression of the vancomycin resistance-associated regulator gene (vraR) and decreased expression of virulence genes (hla, hlb, and coa) and virulence-regulated genes (RNAIII, agrA, and saeR). These results suggested that VraR might have a direct or indirect effect on virulence in S. aureus. In electrophoretic mobility shift assays, VraR did not bind to promoter sequences of hla, hlb, and coa genes, but it did bind to the agr promoter region. In DNase I footprinting assays, VraR protected a 15-nucleotide (nt) sequence in the intergenic region between the agr P2 and P3 promoters. These results indicated that when S. aureus is subject to induction by vancomycin, expression of vraR is upregulated, and VraR binding inhibits the function of the Agr quorum-sensing system, causing reductions in the virulence of VISA/hVISA strains. Our results suggested that VraR in S. aureus is involved not only in the regulation of vancomycin resistance but also in the regulation of virulence.
Klebsiella pneumoniae-associated pathology is largely mediated by neutrophilic inflammation. In this study, we administered Klebsiella pneumoniae to experimental guinea pig groups and the ELR-CXC chemokine antagonist CXCL8(3–72), ceftazidime, and dexamethasone to different groups, respectively. After 24 h, we assessed the animal's pulmonary inflammatory levels, including gross histopathology, airway neutrophilia, lung myeloperoxidase levels, expressions of CXCL8 and TNF, and airway bacterial loads. Compared with ceftazidime and dexamethasone treatments, the administration of the ELR-CXC chemokine antagonist CXCL8(3–72) alone was more effective than other methods, although it did not markedly attenuate the bacterial load. These results suggest new methods for the treatment of Klebsiella pneumoniae pathology.
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