ObjectiveTo review the current progresses in purification strategies, biological characters, and functions of endothelial progenitor cells (EPCs) derived extracellular vesicles (EVs) (EPC-EVs). MethodsRecent relevant publications on the EPC-EVs were extensively reviewed, analyzed, and summarized. ResultsEPC-EVs are usually isolated by differential centrifugation and exhibit a homogenous pattern of spheroid particles with a diameter ranging from 60 to 160 nm under transmission electron microscopy. EPC-EVs are positive for cell-surface markers of EPCs (CD31, CD34, and CD133), and negative for markers of platelets (P-selectin and CD42b) and monocytes (CD14). Recent studies have shown the effectiveness of EPC-EVs in ischemic injuries, anti-Thy1 glomerulonephritis, and cardiomyocyte hypertrophy, and also shown their predictive role in cardio-cerebral-vascular diseases. ConclusionAn alluring prospect exists on the EPC-EVs-related research. Further studies are required to decipher the composition of EPC-EVs and their precise role in pathophysiological processes, and to investigate the molecular mechanisms for their targeting and function.
ObjectiveTo review the mechanisms of bioactive substances of mesenchymal stem cells-derived exosomes (MEX) in tissue repair and analyze the therapeutic values of MEX. MethodRecent relevant literature about MEX for tissue repair was extensively reviewed and analyzed. ResultsThe diameter of exosomes ranges from 30 to 100 nm which contain an abundance of bioactive substances, such as mRNA, microRNA, and protein. The majority of the exact bioactive substances in MEX, which are therapeutically beneficial to a wide range of diseases, are still unclear. ConclusionsBioactive substances contained in the MEX have repairing effect in tissue injury, which could provide a new insight for the clinical treatment of tissue damage. However, further studies are required to investigate the individual differences of MEX and the possible risk of accelerating cancer progression of MEX.
ObjectiveTo review the current progresses in purification strategies, biological characters, and the uses in tissue engineering of urine-derived stem cells (USCs). MethodsRecent relevant publications on the USCs were extensively reviewed, analyzed, and summarized. ResultsUSCs, usually isolated by adherence screening method, are a population of mesenchymal stem cells (MSCs)-like somatic stem cells possessing robust self-renew and multi-potential differentiation ability. Combined with using appropriate biomaterials and biological molecules, USCs can be used as a good cell source for tissue engineering. ConclusionAn alluring prospect exists on the USCs-related research. Further studies are required to investigate the origin, individual differences, and the therapeutic values of USCs.
Objective To construct human recombinant lentiviral expression vector of microRNA-210 (miR-210)and to explore the over-expression of miR-210 on the capillary formation in human umbilical vein endothelial cells 12 (HUVE-12). Methods The recombinant lentiviral expression vector of pGCSIL-green fluorescent protein (GFP)-pre-miR-210 wasconstructed by molecular cloning and transfected to HUVE-12 (LV-miR-210-GFP group), only pGCSIL-GFP was transfectedas control group (LV-GFP group). The miR-210 expression activity was evaluated by GFP reporter through fluorescencedetection and real-time fluorescent quantitative PCR. The ephrinA3 protein expression was measured by flow cytometry. Theconcentration of vascular endothelial growth factor (VEGF) in culture supernatant was determined by ELISA. The cells werecultured in 96-well culture plate coated with Matrigel to assess the abil ity of capillary formation. Results The recombinantplasmid pGCSIL-GFP-pre-miR-210 was confirmed by restriction endonuclease analysis and DNA sequencing. Fluorescencedetection showed that the fluorescence intensity of GFP was highest between 48 and 72 hours after transfection. Real-timefluorescent quantitative PCR showed that the miR-210 expression of LV-miR-210-GFP group was 9.72 times higher than thatin LV-GFP group (t= —11.10，P=0.00). Flow cytometry analysis showed that the positive cell rate of enphrinA3 in LV-miR-210-GFP group (12.52% ± 0.67%) was significantly lower than that in LV-GFP group (73.22% ± 1.45%) (t= —66.12，P=0.00).The concentration of VEGF in supernatant in LV-miR-210-GFP group was significantly higher than that in LV-GFP group[(305.29 ± 16.52) pg/mL vs. (42.52 ± 3.11) pg/mL, t= —27.06，P=0.00]. In vitro capillary-l ike formation assay showed that thenumber of capillaries was significantly larger in LV-miR-210-GFP group than in LV-GFP group (17.33 ± 6.33 vs. 6.33 ± 2.33,t= —2.83，P=0.04). Conclusion The recombinant lentiviral expression vector of miR-210 is constructed successfully andHUVE-12 over-expressing miR-210 can significantly increase the capillary formation, which facil itates further study on themolecular functions of miR-210 in angiogenesis.
ObjectiveTo investigate clinical characteristics and influencing factors of lower respiratory tract infection of Acinetobacter baumannii (AB-LRTI) in respiratory intensive care unit (RICU).MethodsClinical data were collected from 204 RICU patients who were isolated Acinetobacter baumannii (AB). The bacteriological specimens were derived from sputum, bronchoscopic endotracheal aspiration, bronchoalveolar lavage fluid, pleural effusion and blood. The definition of bacterial colonization was based on the responsible criteria from Centers for Disease Control and Prevention/National Medical Safety Network (CDC/NHSN). The patients were divided into three groups as follows, AB colonization group (only AB was isolated, n=40); simple AB-LRTI group (only AB was isolated and defined as infection, n=63), AB with another bacteria LRTI group (AB and another pathogen were isolated simultaneously, n=101). The epidemiology, clinical characteristics and influencing factors of each group were analyzed and compared. ResultsCompared with the AB colonization group, the AB with another bacteria LRTI group had higher proportion of patients with immunosuppression, specimens from sputum and bronchoalveolar lavage fluid, more than 4 invasive procedures, 90-day mortality, white blood cell count >10×109/L (or <4×109/L), neutrophil percent >75% (or <40%), lymphocyte count <1.1×109/L, platelet count <100×109/L, albumin <30 g/L, high sensitivity C-reactive protein >10 mg/L, and neutrophil-to-lymphocyte ratio (NLR). The frequency of bronchoscopy and days of infusing carbapenem within 90 days before isolating AB, the Acute Physiology and Chronic Health Evaluation Ⅱ score, the proportion of patients with invasive mechanical ventilation and the duration of invasive mechanical ventilation in the AB with another pathogen LRTI group were higher than those in the AB colonization group (all P<0.05). Days of infusing carbapenem and β-lactams/β-lactamase inhibitors within 90 days before isolating AB, proportion of septic shock, NLR and 90-day mortality of the patients from the AB with another pathogen LRTI group were more than those in the simple AB-LRTI group (all P<0.05). After regression analysis, more than 4 invasive procedures, or immunosuppression, or with more days of infusing carbapenem within 90 days before isolating AB were all the independent risk factors for AB-LRTI.ConclusionsThere are significant differences in epidemiology, clinical symptoms and laboratory indicators between simple AB-LRTI, AB with another pathogen LRTI and AB colonization in RICU patients. For RICU patients, who suffered more than 4 invasive procedures, immunosuppression, or with more days of infusing carbapenem within 90 days before isolating AB, are more susceptible to AB-LRTI.