Cytotoxicity of silver dressings on diabetic fibroblasts.

A large number of silver-based dressings are commonly used in the management of chronic wounds that are at risk of infection, including diabetic foot ulcers. However, there are still controversies regarding the toxicity of silver dressings on wound healing. The purpose of this study was to objectively test the cytotoxicity of silver dressings on human diabetic fibroblasts. Human diabetic fibroblasts were obtained from the foot skin of four diabetic foot ulcer patients and cultured. The effect of five silver-containing dressing products (Aquacel Ag, Acticoat*Absorbent, Medifoam Ag, Biatain Ag and PolyMem Ag) and their comparable silver-free dressing products on morphology, proliferation and collagen synthesis of the cultured human diabetic fibroblasts were compared in vitro. In addition, extracts of each dressing were tested in order to examine the effect of other chemical components found in the dressings on cytotoxicity. The diabetic fibroblasts cultured with each silver-free dressing adopted the typical dendritic and fusiform shape. On the other hand, the diabetic fibroblasts did not adopt this typical morphology when treated with the different silver dressings. All silver dressings tested in the study reduced the viability of the diabetic fibroblasts and collagen synthesis by 54-70 and 48-68%, respectively, when compared to silver-free dressings. Silver dressings significantly changed the cell morphology and decreased cell proliferation and collagen synthesis of diabetic fibroblasts. Therefore, silver dressings should be used with caution when treating diabetic wounds.

[Effects of water and nitrogen coupling on grain yield formation and nitrogen accumulation, transportation of oil flax in dryland]. / æ°´æ°®è€¦åˆå¯¹æ—±åœ°èƒ¡éº»äº§é‡å½¢æˆä¸ŽèŠ±åŽæ°®ç´ ç§¯ç´¯è½¬è¿çš„å½±å“.

A completely random split zone experiment with irrigation as main plots and nitrogen application rate as sub-plots was carried out to examine the optimal water-nitrogen coupling mode for oil flax planting in dryland. There were three irrigation levels, no irrigation (0 m3·hm-2, I0), irrigation at 1200 m3·hm-2(I1200) and at 1800 m3·hm-2(I1800); and three nitrogen application rates, no nitrogen (0 kg N·hm-2, N0), 60 kg·N hm-2(N60) and 120 kg·N hm-2(N120). We investigated nitrogen accumulation content at different growth stages, nitrogen transport characteristics after anthesis, grain yield and nitrogen utilization efficiency of oil flax. Results showed that the coupling effects of water and nitrogen application on nitrogen uptake in different organs, nitrogen accumulation during different growth stages and grain yield of dry land oil flax varied greatly. Under no irrigation, nitrogen application was beneficial to stem nitrogen absorption at anthesis and maturity stages, but 120 kg N·hm-2 inhibited it at different irrigation levels. At the 1200 m3·hm-2(I1200) irrigation level, foliar nitrogen content at anthesis stage increased first and then decreased with increasing nitrogen rates, and N60 increased foliar nitrogen content by 11.0% and 28.9% respectively compared with N0 and N120. At the 1800 m3·hm-2(I1800) irrigation level, nitrogen application increased foliar nitrogen content at maturity stage, with that in N60 and N120 treatments being 39.7% and 26.9% higher than N0, respectively. The effects of water-nitrogen coupling on nitrogen accumulation in different growth stages of oil flax was mainly shown after budding stage. Under the same irrigation level, N60 promoted and N120 inhibited nitrogen accumulation in each stage after budding. Nitrogen application increased nitrogen transport rate and contribution rate of leaves and stems under I1200 and I1800. The coupling of I1800 and N60 significantly increased the number of effective capsules per plant and grain yield of oil flax (6.6%-22.8%), which was a suitable water-nitrogen coupling management mode in this area.

Effects of simvastatin on iNOS and caspase­3 levels and oxidative stress following smoke inhalation injury.

The overexpression of inducible nitric oxide synthase (iNOS) induces cell apoptosis through various signal transduction pathways and aggravates lung injury. Caspase­3 is an important protein in the apoptotic pathway and its activation can exacerbate apoptosis. Simvastatin, a hydroxymethyl glutaryl­A reductase inhibitor, protects against smoke inhalation injury by inhibiting the synthesis and release of inflammatory factors and decreasing cell apoptosis. Following the establishment of an animal model of smoke inhalation injury, lung tissue and serum were collected at different time points and the protein and mRNA expression of iNOS and caspase­3 in lung tissue by immunochemistry, western blot and reverse transcription­quantitative polymerase chain reaction, the malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in lung tissue and serum were analyzed using thiobarbituric acid method and the WST­1 method. The results were statistically analyzed. The lung tissues of the rats in the saline group and the low­, middle­ and high­dose groups exhibited clear edema and hemorrhage, and had significantly higher pathological scores at the various time points compared with the rats in the control group (P<0.05). Furthermore, lung tissue and serum samples obtained from these four groups had significantly higher mRNA and protein expression levels of iNOS and caspase­3 (P<0.05), significantly lower SOD activity and higher MDA content (P<0.05). Compared with the saline group, the low­, middle­ and high­dose groups had significantly lower pathological scores (P<0.05), significantly lower mRNA and protein expression levels of iNOS, caspase­3 and MDA content in lung tissues (P<0.05) and significantly higher SOD activity in lung tissues and serum. The middle­ and high­dose groups had significantly lower pathological scores (P<0.05), significantly decreased iNOS and caspase­3 mRNA and protein expression in lung tissues, significantly higher SOD activity in lung tissues and serum and a significantly lower MDA content (P<0.05) compared with the low­dose group. With the exception of SOD activity in lung tissues at 24 and 72 h and MDA content in serum at 48 h, no significant differences were observed between the middle­ and high­dose groups. The present study demonstrated that there was an association between the therapeutic effect and dosage of simvastatin within a definitive range. In rats with smoke inhalation injury, simvastatin inhibited iNOS and caspase­3 expression in lung tissues and mitigated oxidative stress, thereby exerting a protective effect. In addition, the effect and dose were associated within a definitive range.

[Corrigendum] Effects of simvastatin on iNOS and caspase­3 levels and oxidative stress following smoke inhalation injury.

After the publication of the above paper, the authors have noticed that the affiliations were presented incorrectly; essentially, Drs Rong­qiang Yang, Peng­fei Guo, Qing­nan Meng, Ya Gao, Imran Khan, Xiao­bo Wang and Zheng­jun Cui are based at the Department of Burn and Repair Reconstruction Surgery, The First Affiliated Hospital of Zhengzhou University, whereas Drs Zhao Ma and Cheng Chang are located at The School of Basic Medical Science of Zhengzhou University. Therefore, the affiliations for this paper should have appeared as follows: Rong­Qiang Yang1, Peng­Fei Guo1, Zhao Ma2, Cheng Chang2, Qing­Nan Meng1, Ya Gao1, Imran Khan1, Xiao­Bo Wang1 and Zheng­Jun Cui1. 1Department of Burn and Repair Reconstruction Surgery, The First Affiliated Hospital of Zhengzhou University; 2The School of Basic Medical Science of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China. The authors regret that these errors with the author affiliations were not noticed prior to the publication of their paper, and apologize for any inconvenience caused. [the original article was published in Molecular Medicine Reports 22: 3405-3417, 2020; DOI: 10.3892/mmr.2020.11413].

[Responses of water consumption characteristics and grain yield of maize to different nitrogen form ratios with full film mulching on double ridges and planting in furrows]. / å ¨è†œåŒåž„æ²Ÿæ’­çŽ‰ç±³è€—æ°´ç‰¹æ€§å’Œç±½ç²’äº§é‡å¯¹ä¸åŒæ°®ç´ å½¢æ€é æ¯”çš„å“åº”.

To optimize the effects of nitrate (NO3--N) to ammonium (NH4+-N) ratios on water consumption characteristics, grain yield and water use efficiency (WUE) of maize under full film mulching on double ridges, a field experiment was conducted at semi-arid Loess Plateau of Gansu Province, China during 2015 to 2017 cropping seasons. The treatments with different ratios of NO3--N to NH4+-N included: N1 (1:0), N2 (1:1), N3 (1:3) and N4 (3:1). The results showed that different NO3--N/NH4+-N ratios had significant impacts on soil water storage in 0-200 cm soil layer. Treatment N3 had the lowest soil water storage. Treatment N4 significantly increased total water consumption by 2.9%, 1.9% and 0.9% in 2015, and 2.3%, 1.4%, and 2.2% in 2017, compared with N1, N2 and N3 treatments, respectively. Compared with the other treatments, treatment N4 increased grain yield by 3.3%-9.9%, 3.5%-24.2% and 8.3%-36.1% and improved WUE by 1.6%-6.8%, 4.9%-21.8%, and 6.6%-32.9% in 2015, 2016 and 2017, respectively. Treatment N4 had the highest partial productivity of nitrogen fertilizer, followed by N2, N3 and N1, respectively. We recommended treatment N4 as the best nitrate and ammonium ratio to improve water use efficiency, N partial productivity, and grain yield of maize in arid and semi-arid Loess Plateau.

[The influence of Ad-AVEGF165 on human malignant melanoma growth in nude mice].

OBJECTIVE: To investigate the effect of antisense VEGF165 infection on the growth of A375 cells in nude mice. METHODS: A375 cells were injected s.c into the axilla of the nude mouse. After the tumor formed, we cut it into 16 pieces equally, then transplanted into another 15 nude mice. There were three groups: Group PBS, Group Ad-GFP, and Group Ad-aVEGF. Four weeks after interfere, the mice were sacrificed and their tumors were excised for naked eye and histological observation. The VEGF expression was checked with ISH and immunohistochemistry staining. The micro-vessel density (MVD) in tumor mass was counted by VIII factor immunohistochemistry staining. RESULTS: The visible and palpable nodules had developed at all the injected sites. Tumor growth speed was more slowly in Group Ad-aVEGF than that in other groups. GFP gene could express effectively in tumor mass. Ad-aVEGF infection could suppress the growth of tumors, and there were no obvious side effects. Ad-aVEGF resulted more tissue necrosis, but it had no obvious effect on cell apoptosis. VEGF expression was inhibited significantly in Group Ad-aVEGF, and MVD was decreased accordingly. CONCLUSIONS: Ad-aVEGF interfere may be a new method against human malignant melanoma, whose main mechanism is to induce ischemia, but not apoptosis.

[Analysis of curative result for keloid with integrated methods].

OBJECTIVE: To study the curative effects of keloid by operation combined with postoperative beta radiation and silicone gel sheeting. METHODS: From 1996 to 2002, 598 patients with keloid (243 males, 355 females, aging 15-55 years with an average of 28.6 years) were treated by integrated therapy. Their disease courses were from 6 months to 6 years. The keloid area ranged from 1.0 cm x 1.5 cm-8.0 cm x 15 cm. First, keloid was removed by operation, and then the wounds were sutured directly (group suture) or covered with skin graft (group graft). In group suture, the operational sites were managed by beta ray radiotherapy 24-48 hours after operation. The total doses of radiation were 12-15 Gy, 5 times 1 week (group suture A) and 10 times 2 weeks (group suture B). Radiotherapy was not taken until stitches were taken out in group graft, and then the same methods were adopted as group suture B. After radiotherapy, silicone gel sheeting was used in 325 cases for 3-6 months. RESULTS: All patients were followed up for 12-18 months. (1) The overall efficacy was 91.3% in group suture A (n = 196), and 95.8% in group suture B (n = 383), respectively. There was significant difference between the two groups (P < 0.01). (2) Radiotherapy was of no effect in 6 cases of group graft (n = 19). (3) Silicone gel sheeting had effectiveness in 185 cases. Silicone gel sheeting had no obvious effect on the overall efficacy, but it could improve the quality of texture and color of skin. CONCLUSION: By use of integrated methods to treat keloid, if the wound can be sutured directly, skin grafting should not be adopted. The results in group suture B are better than those in group suture A; silicone gel sheeting should be used as possible.