Objective To compare the different doses of low-temperature plasma (LTP) on wound healing in BALB/c mice so as to discuss the effects of the optimal dose of low-temperature plasma dealing with wound in mice and the acting mechanism of wound healing.Methods Adoptatmospheric pressure plasma jet discharged by the dielectric barrier was used to treat mouse skin wound.According to the processing time, the wounds were divided into 10s, 20s, 30s, 40s and 50s experimental groups, while naturally healing wounds served as negative controls and the wounds dealt with recombinant human epidermal growth factor served as positive controls.We recorded the wound size every day, observed the histopathological changes, the expression level of type Ⅰ collagen by immunofluorescence, and analyzed the composition of low-temperature plasma jet.Results The wounds with plasma treatment time of 10s, 20s, 30s, and 40s showed significant daily improvement and almost complete closure at days 12, 10, 7, 13, respectively.However, the wounds with plasma treatment time of 50s remained unhealed atday 14.The wounds in positive control group all healed, and the wound healing effect in positive control group could be achieved in 30s group.HE staining and immunofluorescence staining assays showed the optimal result of epidermal cell regeneration, granulation tissue hyperplasia, and collagen deposition in histological aspect at day 7 in 30 s group.The low-temperature plasma jet contained highly reactive free radicals of nitrogen and oxygen, which play an important role in wound healing process.Conclusion Appropriate doses of cold plasma can accelerate wound healing whereas over-doses of plasma can suppress wound healing.The process of wound healing may be related to reactive oxygen and nitrogen species in LTP.

OBJECTIVETo investigate the expression and significance of miR-125a and anti-apoptotic protein Mcl-1 in intestinal tissue after massive small bowel resection in intestinal adaptation.

METHODSSprague-Dawley rats (54 male rats, 8-week old) were divided into 3 groups randomly, including two control groups. Rats in the experiment group were subjected to 70% massive small bowel resection. Rats in the resection group underwent simple intestinal resection and anastomosis. Rats in the control group underwent laparotomy alone. A 5 cm intestine approximately 1 cm distal to the anastomosis was harvested a week after operation. Expression of Mcl-1 was assessed by immunohistochemistry and real-time PCR was used to detect the expression of miR-125a in intestinal tissue.

RESULTSThe positive expression of Mcl-1 in the experiment group was 18.8%(3/16), significantly lower than that in the control group(76.5%, 13/17) and the resection group (83.33%, 15/18)(both P<0.01). The expression of miR-125a in the experiment group was 1.92, significantly higher than that in the control group (1.01) and the resection group (1.05)(both P<0.01).

CONCLUSIONmiR-125a and anti-apoptotic protein Mcl-1 may play an important role in intestinal adaptation process and they may regulate each other through a certain pathway.

Anastomosis, Surgical ; Animals ; Disease Models, Animal ; Intestine, Small ; metabolism ; surgery ; Male ; MicroRNAs ; metabolism ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Rats ; Rats, Sprague-Dawley ; Short Bowel Syndrome ; metabolism

Objective:To analyze the risk factors of bronchopulmonary dysplasia(BPD)in very preterm infants(VPI), and to provide scientific basis for the prevention and treatment of BPD in VPI.Methods:A prospective multicenter study was designed to collect the clinical data of VPI in department of neonatology of 28 hospitals in 7 regions from September 2019 to December 2020.According to the continuous oxygen dependence at 28 days after birth, VPI were divided into non BPD group and BPD group, and the risk factors of BPD in VPI were analyzed.Results:A total of 2 514 cases of VPI including 1 364 cases without BPD and 1 150 cases with BPD were enrolled.The incidence of BPD was 45.7%.The smaller the gestational age and weight, the higher the incidence of BPD( P<0.001). Compared with non BPD group, the average birth age, weight and cesarean section rate in BPD group were lower, and the incidence of male infants, small for gestational age and 5-minute apgar score≤7 were higher( P<0.01). In BPD group, the incidences of neonatal respiratory distress syndrome(NRDS), hemodynamically significant patent ductus arteriosus, retinopathy of prematurity, feeding intolerance, extrauterine growth restriction, grade Ⅲ~Ⅳ intracranial hemorrhage, anemia, early-onset and late-onset sepsis, nosocomial infection, parenteral nutrition-associated cholestasis were higher( P<0.05), the use of pulmonary surfactant(PS), postnatal hormone exposure, anemia and blood transfusion were also higher, and the time of invasive and non-invasive mechanical ventilation, oxygen use and total hospital stay were longer( P<0.001). The time of starting enteral nutrition, cumulative fasting days, days of reaching total enteral nutrition, days of continuous parenteral nutrition, days of reaching 110 kcal/(kg·d) total calorie, days of reaching 110 kcal/(kg·d) oral calorie were longer and the breastfeeding rate was lower in BPD group than those in non BPD group( P<0.001). The cumulative doses of amino acid and fat emulsion during the first week of hospitalization were higher in BPD group( P<0.001). Multivariate Logistic regression analysis showed that NRDS, invasive mechanical ventilation, age of reaching total enteral nutrition, anemia and blood transfusion were the independent risk factors for BPD in VPI, and older gestational age was the protective factor for BPD. Conclusion:Strengthening perinatal management, avoiding premature delivery and severe NRDS, shortening the time of invasive mechanical ventilation, paying attention to enteral nutrition management, reaching whole intestinal feeding as soon as possible, and strictly mastering the indications of blood transfusion are very important to reduce the incidence of BPD in VPI.