The HACEK group microorganisms(Haemophilus parainfluenzae,Aggregatibacter actinomycetem-comitans,Cardiobacterium spp.,Eikenella corrodens,Kingella kingae)belong to Gram-negative bacilli and are members of the normal oropharyngeal microbiota,which can cause invasive opportunistic infection when the host immune barrier is damaged,with infective endocarditis being one of the most serious diseases.HACEK endocarditis is characterized by an insidious course,prolonged delay of diagnosis,and dependence on third-generation cephalo-sporins for treatment.In recent years,with the emergence and development of 16S ribosomal RNA gene sequencing technique,the rapid diagnosis of this disease is expected to be achieved.This paper summarizes the main clinical characteristics and research progress of infective endocarditis caused by HACEK group bacteria,aiming to provide reference for clinical diagnosis and treatment.

The HACEK group microorganisms(Haemophilus parainfluenzae,Aggregatibacter actinomycetem-comitans,Cardiobacterium spp.,Eikenella corrodens,Kingella kingae)belong to Gram-negative bacilli and are members of the normal oropharyngeal microbiota,which can cause invasive opportunistic infection when the host immune barrier is damaged,with infective endocarditis being one of the most serious diseases.HACEK endocarditis is characterized by an insidious course,prolonged delay of diagnosis,and dependence on third-generation cephalo-sporins for treatment.In recent years,with the emergence and development of 16S ribosomal RNA gene sequencing technique,the rapid diagnosis of this disease is expected to be achieved.This paper summarizes the main clinical characteristics and research progress of infective endocarditis caused by HACEK group bacteria,aiming to provide reference for clinical diagnosis and treatment.

Objective: To investigate the relationship between chemosensitivity to L-OHP and expressions of multidrug resistance (MDR) associated factors in lymph node metastases (LNMs) of gastric carcinoma. Methods: The chemosensitivity to L-OHP was measured by MIT assay, and the expressions of P-gp, GST-π, P53, Survivin and Bcl-2 were determined by immunohistochemistry in 54 paired primary tumor (PT) and LNMs of gastric carcinoma. Results: The inhibition rates of LNMs cells for L-OHP were lower than those of PT (P<0.05). The expressions of P-gp, GST-π and Bcl-2 were higher in LNMs than in PT (P<0.05), and no signifi-cant difference was found in the expression of P53 and Survivin between LNMs and PT (P>0.05). Positive cor-relations among P-gp, P53 and Bcl-2 were found in PT and LNMs (r=0.3424, 0.7123, 0.4548, P<0.05). There was no significant difference in the expression of GST-π and Survivin between PT and LNMs (P>0.05). There was statistically negative correlation between inhibition rates and expression of P-gp, GST-π, and Survivin in PT (P<0.05). In LNMs, only Survivin was negatively correlated with inhibition rates of L-OHP (P<0.05). Conclu-sion: The LNMs of gastric carcinoma are heterogeneous with PT in respect to chemosensitivity to L-OHP and expression of multidrug resistance associated factors. The main factors that affect chemosensitivity to L-OHP are also significantly different between PT and LNMs. Effective adjuvant chemotherapy after surgery and re-version to multidrug resistance (MDR) of gastric carcinoma depend on targeting the metastatic lesions of gas-tric carcinoma.