Sequence type 11 (ST11) carbapenem-resistant Klebsiella pneumoniae (CRKP) has become the dominant clone in China. In this review, we trace the prevalence of ST11 CRKP in the China Antimicrobial Surveillance Network (CHINET), the key antimicrobial resistance mechanisms and virulence evolution. The recent emergence of ST11 carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) strains in China due to the acquisition of a pLVPK-like virulence plasmid, which may cause severe infections in relatively healthy individuals that are difficult to treat with current antibiotics, has attracted worldwide attention. There is a very close linkage among IncF plasmids, NTE_KPC and ST11 K. pneumoniae in China. Hybrid conjugative virulence plasmids are demonstrated to readily convert a ST11 CRKP strain to a CR-hvKP strain via conjugation. Understanding the molecular evolutionary mechanisms of resistance and virulence-bearing plasmids as well as the prevalence of ST11 CRKP in China allows improved tracking and control of such organisms.

The aim of this study was to analyze the correlation between dynamic changes in the nasopharyngeal viral load of patients infected with the new coronavirus causing pneumonia and lymphocyte count disease severity. Cases newly diagnosed with COVID-19 at the First Affiliated Hospital of Nanchang University from January 2020 to February 2020 were analyzed retrospectively. Quantitative real-time polymerase chain reaction was used to determine severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from throat swab sample ΔCT values; lymphocyte and lymphocyte subset counts, coagulation system factor levels, myocardial injury indexes, and laboratory biochemical indicators were compared between the mild group and the severe group. The correlation between the relative load of nasopharyngeal SARS-CoV-2 RNA and severe disease symptoms was analyzed. Of the 76 patients, 49 were male and 27 were female. The lymphocyte, CD4⁺ T lymphocyte, and CD8⁺ T lymphocyte counts all differed significantly between the two groups (p < 0.001), as did differences in interleukin (IL)-2R, IL-6, and IL-8 levels (p = 0.022, 0.026, and 0.012, respectively). Moreover, there were significant differences in prothrombin time, D-dimer, and fibrinogen levels between the mild group and the severe group (p = 0.029, 0.006, and <0.001, respectively), and in lactate dehydrogenase and troponin (p < 0.001 and p = 0.007, respectively). SARS-CoV-2 RNA load and lymphocyte count, CD4⁺ T lymphocyte count, and CD8⁺ T lymphocyte count were linearly negatively correlated (p < 0.001). SARS-CoV-2 RNA load was positively correlated with IL-2R, prothrombin time, lactate dehydrogenase, and hypersensitive troponin T (p = 0.002, p = 0.009, and p < 0.001, respectively). In addition, the time that it took for the nucleic acid test to turn negative was significantly shorter for patients in the mild group than for those in the severe group (Z = −6.713, p < 0.001). In conclusion, relative SARS-CoV-2 RNA load in the nasopharynx is closely related to COVID-19 severity. If the relative RNA load was higher, the lymphocyte count was lower, organ damage was greater, and the time it took for the nucleic acid test to turn negative was longer.

 
Background: Previous studies have demonstrated that obstructive sleep apnea (OSA) is associated with abnormal brain structural deficits. However, little is known about the changes in local synchronization of spontaneous activity in patients with OSA. The primary aim of the present study was to investigate spontaneous brain activity in patients with OSA compared with good sleepers (GSs) using regional homogeneity (ReHo) analysis based on resting-state ­functional magnetic resonance imaging (MRI). Methods: Twenty-five untreated male patients with severe OSA and 25 male GSs matched for age and years of education were included in this study. The ReHo method was calculated to assess the strength of local signal synchrony and was compared between the two groups. The observed mean ReHo values were entered into Statistical Package for the Social Sciences software to assess their correlation with behavioral performance. Results: Compared with GSs, patients with OSA showed significantly lower ReHo in the right medial frontal gyrus (BA11), right superior frontal gyrus (BA10), right cluster of the precuneus and angular gyrus (BA39), and left superior parietal lobule (BA7), and higher ReHo in the right posterior lobe of the cerebellum, right cingulate gyrus (BA23), and bilateral cluster covering the lentiform nucleus, putamen, and insula (BA13). The lower mean ReHo value in the right cluster of the precuneus and angular gyrus had a significant negative correlation with sleep time (r=-0.430, P=0.032), and higher ReHo in the right posterior lobe of the cerebellum showed a significant positive correlation with stage 3 sleep (r=0.458, P=0.021) and in the right cingulate gyrus showed a significant positive correlation with percent rapid eye movement sleep (r=0.405, P=0.045). Conclusion: Patients with OSA showed significant regional spontaneous activity deficits in default mode network areas. The ReHo method is a useful noninvasive imaging tool for detection of early changes in cerebral ReHo in patients with OSA.