No abstract

This study determined the serum procalcitonin (PCT) levels in patients with myocardial infarction complicated by pulmonary infection and explore its clinical significance and diagnostic value. A total of 473 patients who were admitted to the Third Affiliated Hospital of Qiqihar Medical University from January 2016 to June 2017 were enrolled as research subjects. Patients were divided into four groups based on their symptom status in myocardial infarction and pulmonary infection. There were 109 patients in normal control group who did not experience symptoms of either myocardial infarction or pulmonary infection. Blood samples were collected from each patient, and PCT levels were measured. The data were analyzed. The serum PCT levels prior to treatment were compared with each other. The PCT levels in the myocardial infarction and the pulmonary infection group were all higher than that in the normal control group (0.040±0.015) (p<0.05). On the contrary, the serum PCT level in the myocardial infarction complicated by pulmonary infection group was higher than that in the normal control group (p<0.001). The serum PCT level after treatment was compared with that before treatment within the same group. The serum PCT levels in the three disease groups were comparable after treatment. The differences in PCT levels before and after treatment were all statistically significant within all three groups (p<0.05). A patient's serum PCT level was correlated with myocardial infarction complicated by pulmonary infection, which suggested it can be used as an important diagnostic marker for this complication. This finding has important clinical value for predicting and evaluating the complicated condition of myocardial infarction and pulmonary infection by providing a more accurate, sensitive, and specific method for early diagnosis of the disease.

Activated macrophages possess tumoricidal ability associated with a cell-cell contact mechanism. However, the nature of the cell surface proteins involved in this tumoricidal process is not yet known. In this research, macrophages activated by bacterium Mycobacterium bovis bacillus Calmette-Guerin (BCG) and by thioglycolate (TGC) were chosen as two comparative models for the large-scale detection of cell surface protein alterations involved in this process. A proteomics approach involving SDS-PAGE followed by LC-MS/MS was used to characterize membrane proteins of the two models. A total of 421 uniquely expressed proteins were identified on the BCG-activated macrophage membrane. Functional groups indicating signal transduction, transport, and cell adhesion, among others, were significantly enriched in this group of proteins. In addition, 42 proteins associated with the plasma membrane were detected. These membrane proteins may contact tumor cells directly and play important roles in the tumoricidal process. In general, this study provides an initial database of candidate proteins that can now be screened as potential regulators of the adherence-dependent tumoricidal properties associated with macrophages.