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Stem cells used for clinical tissue regeneration therapy should have the capacity of self-renewal, high proliferation, and differentiation and be able to be transplanted in large numbers. Although high concentrations of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) may induce the differentiation of stem cells, these factors have been widely used to enhance the propagation of stem cells, including adipose-derived mesenchymal stem cells (ASCs). However, the effects of low concentrations of EGF and bFGF on stem cells need to be evaluated carefully. This study illustrates that low concentrations of EGF (5 ng/mL) and bFGF (10 ng/mL) increase the proliferative ability of ASCs and induce the typical spindle-shaped cell morphology. EGF and bFGF added to medium promoted neural lineage differentiation and impaired the mesodermal differentiation ability of ASCs. This study demonstrates that even low concentrations of EGF and bFGF may limit the differentiation ability of stem cells during stem cell expansion in vitro. EGF and bFGF supplementation should be carefully considered in stem cells for clinical applications.

Aim:To investigate the mechanism leading to in vivo carbapenem resistance development in Klebsiella pneumoniae. Methods: Carbapenemase was detected using the modified carbapenem inactivation method. β-lactamases resistant genes were identified by PCR and sequencing. Clonal relatedness was evaluated by random amplified polymorphic DNA and multiple locus sequence typing. The relationship between sequence typing and resistant genes was analyzed by using the chi-squared test. Results: All ST37 carbapenem-resistant isolates were bla OXA-1 positive and all ST37 carbapenem-sensitive isolates were bla OXA-1 negative at Stage I. A significant relationship between carbapenem resistance and bla OXA-1 was observed. The bla OXA-1 -positive rate was significantly higher in ST37 K. pneumoniae than others. Conclusion: This is the first study about the development of carbapenem resistance in vivo potentially mediated by bla OXA-1 in ST37 K. pneumoniae among neonates.

BackgroundGiven that adolescence is a critical epoch in the onset of schizophrenia, studying aberrant brain changes in adolescent-onset schizophrenia, particularly in patients with drug-naive first-episode schizophrenia, is important to understand the biological mechanism of this disorder. Previous resting-state functional magnetic resonance imaging studies have shown abnormal functional connectivity in separate hemispheres in patients with adult-onset schizophrenia. Our aim to study adolescent-onset schizophrenia can provide clues for the early aetiology of schizophrenia.MethodA total of 48 drug-naïve, first-episode, adolescent-onset schizophrenia outpatients and 31 healthy controls underwent resting-state functional magnetic resonance imaging scans. Data were subjected to voxel-mirrored homotopic connectivity and support vector machine analyses.ResultsCompared with the healthy controls, the adolescent-onset schizophrenia group showed significantly lower voxel-mirrored homotopic connectivity values in different brain regions, including the fusiform gyrus, superior temporal gyrus/insula, precentral gyrus, and precuneus. Decreased voxel-mirrored homotopic connectivity values in the superior temporal gyrus/insula were significantly correlated with Trail-Making Test: Part A performance (r = −0.437, P = .002). A combination of the voxel-mirrored homotopic connectivity values in the precentral gyrus and precuneus may be used to discriminate patients with adolescent-onset schizophrenia from controls with satisfactory classification results, which showed sensitivity of 100%, specificity of 87.09%, and accuracy of 94.93%.ConclusionOur findings highlight resting-state interhemispheric FC abnormalities within the sensorimotor network of patients with adolescent-onset schizophrenia and confirm the relationship between adolescent-onset schizophrenia and adult-onset schizophrenia. These findings suggest that reduced interhemispheric connectivity within the sensorimotor network has a pivotal role in the pathogenesis of schizophrenia.