Heat shock protein A9 (HSPA9), a member of the heat shock protein family, is a putative receptor for Tembusu virus (TMUV). By using Western blot and co-immunoprecipitation assays, E protein domains I and II were identified as the functional domains that facilitate HSPA9 binding. Twenty-five overlapping peptides covering domain I and domain II sequences were synthesized and analyzed by using an HSPA9 binding assay. Two peptides showed the capability of binding to HSPA9. Dot blot assay of truncated peptides indicated that amino acid residues 19 to 22 and 245 to 252 of E protein constitute the minimal motifs required for TMUV binding to HSPA9. Importantly, peptides harboring those two minimal motifs could effectively inhibit TMUV infection. Our results provide insight into TMUV-receptor interaction, thereby creating opportunities for elucidating the mechanism of TMUV entry.
Blotting, Western ; Heat-Shock Proteins ; Hot Temperature ; Humans ; Immunoprecipitation ; Peptides ; Protein Structure, Tertiary

Objective:To evaluate a new type of draw-bar skin stretcher in repair of full-thickness skin defects.Methods:From May 2015 to January 2019, 52 patients with full-thickness skin defects were repaired with a new type of draw-bar skin stretcher at Daping Hospital, Army Medical University. They were 40 males and 12 females, aged from 4 to 61 years (average, 37.1 years). Their skin was stretched for primary wound closure. When primary wound closure failed, skin stretching was performed again to close the wound depending on the wound condition. When the Pinch test was negative after skin stretching, the wound was sutured directly. In cases of positive Pinch test, a skin graft or flap was used to repair the remaining wound. At 12 months after surgery, scar contracture and size of skin graft or flap were observed and wound healing after skin stretching was evaluated in comparison with the original wound.Results:After skin stretching, one-stage wound closure was achieved in 36 cases and multi-stage wound closure in 8 cases; of the remaining 8 cases, 2 were repaired by skin graft and 6 by skin flap after their wounds were reduced by skin stretching. In one-stage closed wounds, infection occurred in 3 cases and marginal necrosis in 5 cases; in the wounds repaired by skin graft or flap, no infection or necrosis was observed. The 12-month follow-up for all the patients showed fine healing of all the wounds after one-stage or multi-stage closure, linear scar, absence of scar contracture, and smaller wound sizes than the original ones after skin graft or flap repair.Conclusions:Skin stretching using our new type of draw-bar skin stretcher is an effective treatment for skin wounds. It can replace traditional skin grafting and flap surgery in some cases, but its indications should be strictly followed to avoid related complications.

Objective: To investigate the effect of papaverine on wound healing of full-thickness skin defect after skin stretching in swine. Methods: Eight Bama pigs were prepared. Standard full-thickness skin defect for 7 cm×7 cm was produced in the middle part of each pig's forelimb, and skin traction was used to close the wound. According to random number table method, the pigs were divided into experiment group and control group, with four pigs in each group. Percutaneous oxygen partial pressure (TcPO₂) was compared preoperatively and postoperatively. Wound healing clinical score was evaluated four and 10 days after operation. Weidner counting method was employed to determine the microvascular density (MVD) of the wound edge tissue 0 and 10 days after operation. Immunohistochemistry was used to observe the expression of hypoxia inducible factor 1-α (HIF- 1α) and vascular endothelial growth factor (VEGF) 0, 4 and 10 days after operation. Results: There was no statistically significant difference in TcPO₂ between the experiment group [(55.1±5.4)mmHg] and the control group [(54.7±5.9)mmHg] before skin stretching (P>0.05), while statistically significant difference was found after stretching [(22.7±3.3)mmHg vs. (16.4±3.4)mmHg] (P<0.01). There was no statistically significant difference in clinical wound healing scores between the control group and experiment group 4 days after skin stretching [(2.6±0.7)points vs. (2.1±0.4)points] (P>0.05), but better result was found in experiment group compared with the control group in 10 days [(1.3±0.5)points vs. (4.6±0.7)points] (P<0.01). MVD of skin tissue showed no statistically significant difference between the control group (8.5±1.3) and the experiment group (9.3±1.2) immediately after skin stretching (P>0.05), while the MVD of wound skin tissue in the experiment group (29.5±4.8) was significantly higher than that in the control group (21.1±3.4) 10 days after skin stretching (P<0.01). After skin stretching, the HIF-1 alpha expression in experiment group was significantly higher than the control group 4 days after skin stretching [(50.0±7.0) vs. (38.6±7.0)] (P<0.01), but no statistical significance was found between that at 0 day and 10 days(P>0.05). The expression of VEGF in the wound skin tissues of the experiment group was significantly higher than that of the control group [(49.9±10.8) vs. (39.2±6.3)] at 4 days after skin stretching (P<0.05), while no statistically significance was found at 0 and 10 days (P>0.05). Conclusion For full-thickness skin defect after skin stretching in pigs, papaverine can alleviate small vessel spasm, improve skin edge oxygen supply, and promote the growth of microvessels, thus promoting the healing, which might be associated with the increase of HIF-1ɑ and VEGF expression.

OBJECTIVE：To improve the quality standard of Taraxaci Herba ，and to evaluate the quality of T. officinale from different origins. METHODS ：Based on the provisions of the 2020 edition of Chinese Pharmacopoeia （part Ⅰ）under the item “Taraxaci Herba ”，the method of content determination was added for the detection of water-soluble extracts （hot extraction method）and alcohol-soluble extracts （hot extraction method ），total flavonoids ，chlorogenic acid ，caffeic acid ，cichoric acid and isochlorogenic acid A. HPLC fingerprint was established by using 42 batches of T. officinale from 8 producing areas as object ，and principal component analysis was performed on the basis of above results. RESULTS ：The contents of alcohol-soluble extracts in 42 batches of T. officinale were 15.30％-30.40％，and those of water-soluble extracts were 27.59％-38.96％. The concentration of total flavonoids（UV spectrophotometry ），chlorogenic acid ，caffeic acid ，cichoric acid and isochlorogenic acid A （HPLC method ）were 0.016-0.096，0.003-0.196，0.004-0.117，0.025-1.578，0.002-0.152 mg/mL，respectively （all R2＞0.999）；RSDs of precision ， stability and repeatability tests were all lower than 2.00％（n＝6）；average sample recovery were 98.97％-103.53％，and RSDs were 1.19％-1.58％. The contents of total flavonoids ，chlorogenic acid ，caffeic acid ，cichoric acid and isochlorogenic acid A were 0.734％ -3.700％ ，0.004％ -0.123％ ，0.006％ - 0.087％ ，0.073％ -1.499％ ，0.005％ -0.109％ respectively in 42 batches of T. officinale. For 42 batches of T. officinale samples in HPLC fingerprint ，RSDs of the relative retention time of the common peak were 0-0.94％，and RSDs of the relative peak area were 0-125.57％. Among them ，the similarity of 39 batches of samples was all higher than 0.900. Results of principal component analysis showed that the quality of T. officinale from Shaanxi province was better，followed by medicinal materials from Hebei province. CONCLUSIONS ：Tentatively，the contents of alcohol-soluble extract，water-soluble extract ，total flavonoids ，chlorogenic acid ，caffeic acid ，cichoric acid and isochlorogenic acid A shall not be less than 17.0％，27.0％，1.383％，0.024％，0.021％，0.450％，0.021％ for Taraxaci Herba. In addition to the low content of caffeic acid in T. officinale from Shaanxi province ，the other indexes were better ；the content of caffeic acid in T. officinale from Hebei province was higher than that from Shaanxi province ，and other indicators were slightly lower than that from Shaanxi province. The quality of comprehensive evaluation of T. officinale from other origins was relatively poor ，and the quality of different batches of medicinal materials from the same origin was unstable.