A highly sensitive fluorescence spectroscopic method was established for the selective determination of estradiol, which took advantages of the excellent molecular recognition capability of aptamer and the energy transfer between the specific fluorescent groups. The effects of the pH value, buffer constituent and concentration, the concentration of DNA, the experimental temperature and response time on the detection of estradiol were studied. Under the optimal conditions (50 mmol/L BR buffer solution with pH value at 7. 4, 1. 0×10-7 mol/L for each DNA strand, incubation at 45 ℃, response time 19 min), the change of the fluorescence intensity (ΔI) versus the logarithm of the concentration of estradiol ( lgC) was linear over a concentration range from 1. 0×10-11 mol/L to 5. 0×10-9 mol/L with good linear correlation (r=0. 9953). The limit of detection (LOD) was found to be 6. 0×10-12 mol/L (S/N=3). This method was successfully applied to the detection of estradiol in human urine, with the recovery in the range of 94. 0%-103. 5%. This method showed good precision and accuracy.

How to promote rapid wound healing and reduce scar hyperplasia is an urgent problem to be solved in plastic surgery. Mesenchymal stem cells (MSCs) is a research hotspot in current cell therapy. The author reviewed the literature and summarized the mechanism of the MSCs effect on the macrophage. MSCs release multiple soluble cytokines, leading the polarization of anti-inflammatory type M2 cell which can reduce the inflammatory cytokines and promote tissue repair and regeneration.The writer concluded that the polarization effect of mesenchymal stem cells on macrophages provides a new therapeutic strategy and theoretical basis for solving the problem of wound healing.

Objective To explore the underlying mechanism of β2 adrenergic receptor(ADRB2)in fibrogenesis during wound healing.Methods Non-specific ADRB2 gene knockdown adeno-associated virus(AAV-ADRB2 group,6 mice)and control virus(AAV-NC group,6 mice)was injected randomly into the back skin of 12 mice for 21 days,a full-thickness skin defected wound healing murine model was established.Wound healing rates were recorded at the 1st,3rd,5th,and 7th day after operation.Histological examinations by H-E staining,Masson staining,and immunohistochemistry were conducted to observe wounded skin tissue structure,fibrosis,and α-SMA protein expression;quantitative PCR was employed to analyze ADRB2 and matrix metalloproteinase(MMP)mRNA levels;Western blotting was utilized to assess the protein expression levels of COL1A1,COL3A1,TGF-β1,and Smad3.Results On postoperative day 5 and 7,the wound healing rate of the AAV-ADRB2 group significantly decreased(P＜0.05),accompanied by a series pathological changes,including thickened epidermis,exaggerated inflammation,reduced fibroblast count,and inhibited collagen deposition;the α-SMA expression showed a significant decrease(P＜0.05),and the ratio of COL1A1 to COL3A1 decreased(P＜0.05);ADRB2 mRNA levels significantly decreased(P＜0.01),while MMP-1 and MMP-8 mRNA levels increased(P＜0.01);the protein levels of TGF-β1 and Smad3 exhibited a significant decrease(P＜0.05).Conclusions ADRB2 knockdown reduced fibrosis during wound healing and degenerated connective tissue content around the wound bed by inhibiting the TGF-β1/Smad3 signaling pathway,which leads to an increase in MMP mRNA levels and a decrease in the ratio of type Ⅰ to type Ⅲ collagen.

Objective:To investigate the psychological stress and related factors of community medical staff in Shanghai during infectious public health emergencies.Methods:Random cluster sampling, questionnaires combining general demographic information, self-rating anxiety scale(SAS), self-rating depression scale(SDS)and yale-brown obsessive compulsive scale(YB)were administrated to investigate the psychological stress of medical staff from 20 community healthcare centers in 10 Shanghai districts.Results:A total of 696 valid questionnaires were collected. 17.36% of the staff had SAS scores exceeding the boundary value. Nurses, staff with per capita monthly family income<5 000 yuan, or with below-average family relations presented higher SAS scores. 28.19% of the staff had SDS scores exceeding the boundary value. Staff with 5-10 years seniority, nurses, with per capita monthly family income<5 000 yuan, and with poor family relations presented higher SDS scores. 6.68% of the staff had YB score≥16. Nurses presented a higher YB score.Conclusions:Some community healthcare center staff experienced psychological stress during public health emergencies.Factors associated with psychological stress, such as 5-10 years′ seniority, nurses, per capita monthly family income<5 000 yuan, below-average or poor family relations, deserve more attention in order to prevent from or alleviate harmful psychological stress.