BACKGROUND Klebsiella pneumoniae(K.pneumoniae)used to affect mainly people with compromised immunity or weakened by other infections,but recent emergence of hypervirulent strains has increased infections even in healt...BACKGROUND Klebsiella pneumoniae(K.pneumoniae)used to affect mainly people with compromised immunity or weakened by other infections,but recent emergence of hypervirulent strains has increased infections even in healthy individuals.These infections include liver abscess,pneumonia,bacteremia,meningitis,necrotizing fasciitis,and endophthalmitis.Although metastatic infection by hypervirulent K.pneumoniae(hvKP)is increasingly recognized,co-infection with Cryptococcus neoformans(C.neoformans)meningitis in immunocompetent hosts is rare but fatal.So,it is necessary to determine the risk factors,complications,and comorbidity of this disease.CASE SUMMARY This report describes a 58-year-old man with hvKP pulmonary abscess,bacteremia,and meningitis,accompanied by fatal Cryptococcus meningitis.This patient presented with fever for 1 wk and drowsiness for 3 d.Laboratory findings revealed pulmonary abscess and bacteremia of K.pneumoniae.He was given intravenous antibiotic therapy,and the infection was under control for about 1 wk.However,his condition deteriorated rapidly because of metastatic purulent meningitis.Although hvKP and C.neoformans were isolated and confirmed,the patient died of spontaneous respiratory and cardiac arrest caused by cerebral hernia.CONCLUSION HvKP has emerged as a cause of metastatic infections in immunocompetent hosts.polymicrobial co-infections should be taken into consideration when metastatic infection is present.展开更多
This paper is motivated by the concept of the signed k-domination problem and dedicated to the complexity of the problem on graphs. For any fixed nonnegative integer k, we show that the signed k-domination problem is ...This paper is motivated by the concept of the signed k-domination problem and dedicated to the complexity of the problem on graphs. For any fixed nonnegative integer k, we show that the signed k-domination problem is NP-complete for doubly chordal graphs. For strongly chordal graphs and distance-hereditary graphs, we show that the signed k-domination problem can be solved in polynomial time. We also show that the problem is linear-time solvable for trees, interval graphs, and chordal comparability graphs.展开更多
基金Supported by Science and Technology Planning Project of Guangdong Province of China,No.2017A020215177
文摘BACKGROUND Klebsiella pneumoniae(K.pneumoniae)used to affect mainly people with compromised immunity or weakened by other infections,but recent emergence of hypervirulent strains has increased infections even in healthy individuals.These infections include liver abscess,pneumonia,bacteremia,meningitis,necrotizing fasciitis,and endophthalmitis.Although metastatic infection by hypervirulent K.pneumoniae(hvKP)is increasingly recognized,co-infection with Cryptococcus neoformans(C.neoformans)meningitis in immunocompetent hosts is rare but fatal.So,it is necessary to determine the risk factors,complications,and comorbidity of this disease.CASE SUMMARY This report describes a 58-year-old man with hvKP pulmonary abscess,bacteremia,and meningitis,accompanied by fatal Cryptococcus meningitis.This patient presented with fever for 1 wk and drowsiness for 3 d.Laboratory findings revealed pulmonary abscess and bacteremia of K.pneumoniae.He was given intravenous antibiotic therapy,and the infection was under control for about 1 wk.However,his condition deteriorated rapidly because of metastatic purulent meningitis.Although hvKP and C.neoformans were isolated and confirmed,the patient died of spontaneous respiratory and cardiac arrest caused by cerebral hernia.CONCLUSION HvKP has emerged as a cause of metastatic infections in immunocompetent hosts.polymicrobial co-infections should be taken into consideration when metastatic infection is present.
文摘This paper is motivated by the concept of the signed k-domination problem and dedicated to the complexity of the problem on graphs. For any fixed nonnegative integer k, we show that the signed k-domination problem is NP-complete for doubly chordal graphs. For strongly chordal graphs and distance-hereditary graphs, we show that the signed k-domination problem can be solved in polynomial time. We also show that the problem is linear-time solvable for trees, interval graphs, and chordal comparability graphs.
