BACKGROUND:Present treatments for chronic skin wounds have certain limitations, and adult stem cels play a potentialpart in cutaneous repair and regeneration.
OBJECTIVE:To review effects of stem cels in skin regeneration and wound healing.
METHODS:The first author retrieved CNKI and Medline databases by computer for relevant articles published from 2000 to 2010. Thekeywords were “epidermal stem cels, hair folicle stem cels, stem cels, transplantation, dermal stem cels” in Chinese and in English, respectively. Then totaly 489 papers were obtained after initial survey, and according to the inclusion criteria, 30articles were selected for review.
RESULTS AND CONCLUSION:Epidermal stem cels and other adult stem celshave beenapplied to treat wounds and other skin diseases. Epidermal stem celsarethe crucialcelsource of skin development, repairandremodeling.Epidermal stem celsarealwaysina resting statein vivo.Unless,skin injure or culturein vitro, celdivision and proliferation wilbe significantly fastened. The stability of the epidermis mainly dependson the asymmetric divisionof a subpopulation, in which two daughter celsare produced, including one with characteristics of stem cels, and the other differentiated into transient amplifying cels that wil be differentiated intopost mitotic celsafter a series of cel divisions (3-5 times). Afterwards, those post mitotic celsaredeveloped into terminal differentiation cels onthe basal layer, finaly detachfromthe epidermisasdander. In addition, it is unclear whether epidermal factors are related to apoptosis, migration and differentiation in the process of wound repairandeven under physiological conditions. Therefore, application ofstem celsinwound healing requiresa further discussion.

Two hundred cases of early pregnant women to receiveartificial abortion were randomly divided into 4groups,viz.analgesic solution,dicaine,normal saline,and blank control groups of which the action on dilata-tion of uterus and of mitigating the comprehensive re-actions to artificval abortion were observed.Resultsrevealed that the analgesic solution and dicaine groupshad better effect on dilatation of uterus and ameliorat-ing the reactions of artificial abortion,analgesic solu-tion was especially good at mitigating the comprehen-sive reactions to artificial abortion than the dicainegroup.

Objective To explore the role of pulmonary function analysis in drug efficacy evaluation of radiation-induced lung injury.Methods Totally 30 C57BL/6 mice were randomly divided into 3 groups:control group, radiation group and dexamethasone group.Mice in radiation group and dexamethasone group were irradiated with 20 Gy X-ray on the whole chest.Then mice in dexamethasone group was intraperitoneally injected with dexamethasone at the dose of 4.5 mg/( kg· d) for 2 weeks and then the dose was halved up to 1 month after radiation while control group and radiation group were intraperitoneally injected with 0.9%saline.One month after irradiation, pulmonary function of all the mice was tested with EMKA system.Then mice were sacrificed and pathological changes of pulmonary tissue were observed by HE staining. Furthermore, the area of alveolar cavity was measured with the Image-pro plus software.Results One month after irradiation, the pulmonary function parameters of mice in radiation and dexamethasone groups, such as mid-expiratory flow, minute volume,tidal volume,peak inspiratory flow,and peak expiratory flow,decreased obviously compared with the control group, but those parameters of the dexamethasone group decreased much less significantly than in the radiation group.The pathological changes of pulmonary tissues showed that the area of alveolar cavity of radiation group and dexamethasone group was smaller than that of the control group, but the extent of the loss of alveolar cavity area of the dexamethasone group was less than in the radiation group.Neutrophils infiltration could be found in the radiation group and dexamethasone group, but was less serious in the dexamethasone group.The result of pulmonary function analysis was coincident with pathological changes of the lung.Conclusion Dexamethasone can alleviate radiation induced pulmonary injury.Pulmonary function analysis combined with pathological observation of pulmonary tissues can effectively evaluate the efficacy of drugs in radiation induced lung injury.

Objective:To explore the mediating role of working memory (WM) in the cortisol-awakening response (CAR) and multiple object tracking (MOT) in children with attention deficit hyperactivity disorder (ADHD).Methods:92 children with ADHD (ADHD group) and 94 typically developing children (control group) were selected from January 2022 to October 2022. Salivary cortisol levels were detected and analyzed in all children at four time points after awakening. Children's WM and MOT performance were assessed by the 1-back and MOT paradigms, respectively. SPSS 26.0 software was used for t-test and Pearson correlation analysis of the data, and plug-in PROCESS model 4 of SPSS 26.0 was used for mediated effects analysis. Results:(1) ADHD group showed significantly lower CAR, 1-back accuracy and MOT performance((30.97±5.63), (81.33±10.64) %, (2.36±0.37)) than the control group((32.41±3.48), (91.19±7.12) %, (2.62±0.28))( t=-2.09, -7.22, -5.31, all P<0.05). (2) Pearson analysis showed that CAR was positively correlated with 1-back accuracy ( r=0.293, P<0.01) and MOT performance ( r=0.740, P<0.01). 1-back accuracy was positively correlated with MOT performance ( r=0.368, P<0.01). (3) WM partially mediated the effect of CAR on MOT in children with ADHD, accounting for 6.13% (0.003/0.049) of the total effect. Conclusion:Children with ADHD have deficits in MOT.WM plays a mediating role between CAR and MOT performance in children with ADHD.