ZA6-1锌合金骨植入体表面沉积抗菌及耐腐蚀型生物活性涂层

通过在商用ZA6-1锌合金表面沉积负载十二烷基硫酸钠(SDS)和乙酰丙酸(LA)的聚乳酸羟基乙酸共聚物(PLGA)赋予其抗菌性能。首先,在ZA6-1锌合金表面聚合化沉积APTES接枝层,获得氨基官能团;随后,利用氨基官能团与羧基官能团的正负电荷吸引作用使与SDS/LA混合的PLGA负载于基体表面。所制备的PLGA−SDS/LA涂层具有良好的耐腐蚀能力,其腐蚀速率低至0.005 mm/a,并且可通过改变涂层厚度对其进行调控。该涂层除具有良好的成骨细胞相容性外,还具有优良的抗菌性能,其对金黄色葡萄球菌和大肠杆菌的抗菌率分别达到98.9%和99.8%。

High dose glargine alters the expression profiles of microRNAs in pancreatic cancer cells

AIM: To investigate the effect of high dose glargine on the expression profiles of microRNAs in human pancreatic cancer cells. METHODS: Real-time polymerase chain reaction array (RT-PCR) was applied to investigate miRNAs differentially expressed in Sw1990 cells treated with or without 100 IU/L glargine. Stem-loop RT-PCR was used to confirm the results of the array assay in Sw1990 and Panc-1 cells. The effects of miR-95 on cell growth, apoptosis, invasion and migration abilities were respectively examined by CCK8 assay, apoptosis assay, Matrigel invasion and migration assay in Sw1990 and Panc-1 cells. Nude mice xenograft models with Sw1990 cells were built to investigate pancreatic cancer growth in vivo after transfection by the lentivirus pGLV3-GFP-miR-95. RESULTS: Ten miRNAs were significantly up-regulated and 2 miRNAs down-regulated in glargine treated Sw1990 cells when compared with non-treated cells (2.48-fold changes on average, P < 0.01). miR-95, miR-134 and miR-34c-3p are the top three miRNAs regulated by glargine (3.65-fold, 2.67-fold and 2.60-fold changes respectively, P < 0.01) in Sw1990 cells. Stem-loop RT-PCR confirmed that high dose glargine up-regulated the expression of miR-95 and miR-134 in both Sw1990 and Panc-1 cells. The most obvious change is the apparent increase of miR-95. Forced expression of miR-95 significantly increased cell proliferation (Sw1990: 2.510 ± 0.129 vs 2.305 ± 0.187, P < 0.05; Panc-1: 2.439 ± 0.211 vs 2.264 ± 0.117, P < 0.05), invasion (Sw1990: 67.90 ± 12.33 vs 47.30 ± 5.89, P < 0.01; Panc-1: 37.80 ± 8.93 vs 30.20 ± 5.14, P < 0.01), migration (Sw1990: 101 ± 6.00 vs 51.20 ± 8.34, P < 0.01; Panc-1: 91.80 ± 9.22 vs 81.50 ± 7.47, P < 0.01) and inhibited cell apoptosis (Sw1990: 22.05% ± 1.92% vs 40.32% ± 1.93%, P < 0.05; Panc-1: 20.17% ± 0.85% vs 45.60% ± 1.43%, P < 0.05) when compared with paired negative controls, whereas knockdown of miR-95 obtained the opposite effect. Nude mice xenograft models confirmed that miR-95 promoted the growth of pancreatic cancer in vivo when compared with negative control (tumor volume: 373.82 ± 23.67 mLvs 219.69 ± 17.82 mL,P < 0.05). CONCLUSION: These observations suggested that mod- ulation of miRNA expression may be an important mechanism underlying the biological effects of glargine.

Establishment and evaluation of O/W type-based microemulsion on crossbow medicine of the Miao ethnic group

Background:Crossbow medicine needle is a traditional external therapy.However,acupuncture pain,inaccurate administration,secondary infection,and poor patient compliance limit the application of specialty therapies.Since the most effective components of crossbow medicine are lipid-soluble,the crossbow medicine needle was prepared as an innovative O/W-type microemulsion to solve these problems.In this study,the crossbow medicine microemulsion preparation method was established and its quality was evaluated.Methods:A single factor and pseudoternary phase diagram,combined with a D-optimal mixture design,optimized the formulation of crossbow medicine microemulsion through particle size,polydispersity index,zeta potential,microstructure,and contents of benzoyl neoaconitine,benzoyl hypoaconitine,neoaconitine,periplocin,and methyl salicylate to evaluate the final prescription.Results:The best prescription for preparing crossbow medicine microemulsion is 0.1500 g crossbow medicine dry extract,0.1500 g isopropyl myristate,0.8625 g polyoxyethylene castor oil-35,0.2875 g ethanol,3.700 g water,and 5.1500 g microemulsion.The prepared microemulsion is an oil-in-water type with a clear and transparent appearance.Its average particle size is 19.83±0.78 nm,average polydispersity index is 0.15±0.02,and average zeta potential is−0.51±0.1 mV.The pH value is 5.17±0.02.The microstructure of crossbow medicine microemulsion illustrated a uniform distribution of spherical oil globules.The average contents of benzoyl neoaconitine,benzoyl hypoaconitine,neoaconitine,periplocin,and methyl salicylate were 13.34,113.05,43.45,628.27 and 27.93μg/g,respectively.Conclusion:The preparation process of crossbow medicine microemulsion is reasonable and feasible.The method to determine the content is accurate and straightforward,laying the foundation for further research.

In vitro evaluation of transdermal permeation effects of Fu’s cupping therapy via six diffusion kinetics models

In this study,six kinetics models of indomethacin hydrophilic gel patch transdermal in vitro release was established,including zero-level,first-order,Higuchi-level,Ritger-Peppas,Weibull and Hixcon-Crowell dynamic equations.The chemical permeation enhancers,including 3%and 5%Azone,and iontophoresis were used as the control.Transdermal diffusion tests were performed in vitro and indomethacin was quantified by high performance liquid chromatography system.The transdermal parameter of the Higuchi and Weibull dynamic equations,indicated that Fu’s cupping therapy(FCT)could significantly improve Higuchi and Weibull kinetic parameters in vitro transdermal,increased transdermal rate and permeability coefficient,reduced lagging time.Additionally,statistical analysis speculated the skin barrier function could be restored after 46 h treatment.Hence,as a new physical transdermal drug delivery technology,transdermal permeation effects produced by FCT are obvious,which has the characteristics of traditional Chinese medicine and has important clinical application value.

Artificial neural network techniques to predict the moisture ratio content during hot air drying and vacuum drying of Radix isatidis extract

Background:To predict the moisture ratio of Radix isatidis extract during drying.Methods:Artificial neural networks were designed using the MATLAB neural network toolbox to produce a moisture ratio prediction model of Radix isatidis extract during hot air drying and vacuum drying,where regression values and mean squared error were used as evaluation indexes to optimize the number of hidden layer nodes and determine the topological structure of artificial neural networks model.In addition,the drying curves for the different drying parameters were analyzed.Results:The optimal topological structure of the moisture ratio prediction model for hot air drying and vacuum drying of Radix isatidis extract were“4-9-1”and“5-9-1”respectively,and the regression values between the predicted value and the experimental value is close to 1.This indicates that it has a high prediction accuracy.The moisture ratio gradually decreases with an increase in the drying time,reducing the loading,initial moisture content,increasing the temperature,and pressure can shorten the drying time and improve the drying efficiency.Conclusion:Artificial neural networks technology has the advantages of rapid and accurate prediction,and can provide a theoretical basis and technical support for online prediction during the drying process of the extract.

Learning curve for a surgeon in robotic pancreaticoduodenectomy through a“G”-shaped approach:A cumulative sum analysis

BACKGROUND Robotic pancreaticoduodenectomy(RPD)can achieve similar surgical results to open and PD;however,RPD has a long learning curve and operation time(OT).To address this issue,we have summarized a surgical path to shorten the surgical learning curve and OT.AIM To investigate the effective learning curve of a“G”-shaped surgical approach in RPD for patients.METHODS A total of 60 patients,who received“G”-shaped RPD(GRPD)by a single surgeon in the First Hospital of Shanxi Medical University from May 2017 to April 2020,were included in this study.The OT,demographic data,intraoperative blood loss,complications,hospitalization time,and pathological results were recorded,and the cumulative sum(CUSUM)analysis was performed to evaluate the learning curve for GRPD.RESULTS According to the CUSUM analysis,the learning curve for GRPD was grouped into two phases:The early and late phases.The OT was 480±81.65 min vs 331±76.54 min,hospitalization time was 22±4.53 d vs 17±6.08 d,and blood loss was 308±54.78 mL vs 169.2±35.33 mL in the respective groups.Complications,including pancreatic fistula,bile leakage,reoperation rate,postoperative death,and delayed gastric emptying,were significantly decreased after this surgical technique.CONCLUSION GRPD can improve the learning curve and operative time,providing a new method for shortening the RPD learning curve.

A valid evaluation method for UPLC fingerprint analysis and moisture ratio prediction model:application to microwave vacuum drying of Radix isatidis extract

Background:Drying is a necessary component of traditional Chinese medicine extracts.The heating principle of microwave vacuum drying is different from that of the conventional heat method.However,at present,there is paucity of information on the drying process of traditional Chinese medicine extract by microwave vacuum drying,and the results of such process are unclear.Methods:To study the dynamic changes in the chemical characteristics of microwave vacuum drying under different drying conditions,ultrahigh-performance liquid chromatography fingerprint profiles were established using Radix isatidis extract as a model drug and analyzed using similarity analysis,partial least squares-discriminant analysis,and semi-quantitative analysis.In addition,a backpropagation artificial neural network model was developed to predict the moisture ratio of the drying process.Results:Qualitative results showed that the similarity between different drying conditions was greater than 0.95,and 2 amino acid components(peaks 5 and 6)affected by process fluctuations were screened out.The quantitative results showed that the mass concentration of component 1 fluctuated after drying,while that of component 2 increased.The optimal backpropagation artificial neural network model structure used to predict the moisture ratio was 5-4-1,with regression and mean squared error values of 0.996 and 0.0003,respectively,after training,which were well fitted and had a strong approximation ability.Conclusion:Upon comparison of fingerprints and the evaluation of statistical methods,common components of Radix isatidis extract had little variation under different drying conditions,and the selected components provided a reference for the establishment of process evaluation indexes.The establishment of backpropagation artificial neural network provides a theoretical basis for the application of microwave vacuum drying technology and online monitoring of moisture ratio.

Numerical simulation of partial-interaction load-deflection behavior of corroded reinforced concrete beams based on a segmental approach and evaluation of reinforcement corrosion level

Corrosion of reinforcement has a significant effect on the deformation of reinforced concrete beams by deteriorating the bond-slip characteristics, diminishing the cross-sectional area of reinforcement, and causing cracking. The traditional way of quantifying the load capacity and simulating deflection is the moment-curvature(M/χ) approach. The problem is that the M/χ approach is semi-empirical after cracking as it is strain-based and cannot allow for tension stiffening. This paper introduces the new displacement-based moment-rotation(M/θ) approach which directly simulates the development of cracks and hence allows for tension stiffening. This M/θ approach is then used to predict the load-deflection behavior of reinforced concrete beams with corrosion effect by incorporating the corrosion-affected bond-slip model. The bond-slip model only considers the corrosion effect but ignores the confinement effect. It is used here as an example to describe the procedure of how to quantify the corrosion effect on reinforced concrete beam behavior. The load-deflection curves obtained from the numerical simulation show a good agreement with test results. For reinforced concrete beams with confinement, the only difference is to replace the bond-slip model with the one which includes both corrosion and stirrup effects. Additionally, the paper shows how to use the M/θ approach with the bond-slip model to predict the real corrosion level of reinforcement in some tests in which only the theoretical corrosion levels are provided.