Pluronic lecithin organogel of 5-aminosalicylic acid for wound healing

5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-β) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p?相似文献   

A Multifunctional Pro‐Healing Zwitterionic Hydrogel for Simultaneous Optical Monitoring of pH and Glucose in Diabetic Wound Treatment

Diabetic ulcer is the most common kind of chronic wound worldwide. Though great efforts have been devoted, diabetic ulcer still remains as a challenge that requires constant monitoring and management. In this work, a multifunctional zwitterionic hydrogel is developed to simultaneously detect two fluctuant wound parameters, pH and glucose level, to monitor the diabetic wound status. A pH indicator dye (phenol red) and two glucose sensing enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), are encapsulated in the anti‐biofouling and biocompatible zwitterionic poly‐carboxybetaine (PCB) hydrogel matrix. The visible images are collected by a smartphone and transformed into RGB signals to quantify the wound parameters. Results show that the activity and stability of both two enzymes are improved within PCB hydrogel, and the K_cat/K_m value of PCB‐HRP is ≈5.5 fold of free HRP in artificial wound exudate. This novel wound dressing can successfully monitor the pH range of 4–8 and glucose level of 0.1–10 × 10^?3 m . Meanwhile, it also provides a moist healing environment that can promote diabetic wound healing. This multifunctional wound dressing may open vistas in chronic wound management and guide the diabetes treatment in clinical applications.     

基于多尺度子带能量集特征的膛口波识别方法

面向实际复杂环境下的枪声探测应用,提出一种基于多尺度子带能量集特征的膛口波识别方法。采用一组低频子带滤波器增强膛口波信号,通过膛口波检测和波峰搜索确定候选膛口波的起点位置,并基于该起点以嵌套方式截取候选膛口波及其各子带分量的多尺度数据片段,用各片段数据的短时能量和能量比构成多尺度子带能量集特征输入支持向量机和k近邻分类器,进行膛口波和非膛口波识别。对372段外场实录枪声数据进行数值实验,结果表明：所提方法对膛口波识别的查全率、查准率均高于93%,加权调和平均高于0.95;两种分类器下的识别结果无明显差别,但所用特征维数和计算耗时却远低于常用的离散小波方法,更接近实际应用需求。     

低秩及几何约束的嵌入式阵列膛口波测向方法

针对部分阵元受壳体遮挡导致的小型嵌入式麦克风阵列枪声探测系统目标定位偏差问题,提出了一种枪声膛口波测向新方法。该方法通过分析非通视传播对阵元间波达时间差（TDOA）的不利影响,采用低秩及几何约束下的凸优化校正算法抑制实测TDOA矩阵中的随机噪声和衍射传播偏差;同时选取距离目标最近的通视麦克风作为参考阵元,进一步减小最小二乘测向偏差的统计均值与方差。外场试验结果表明,膛口波测向误差不大于实际产品指标要求的累积概率,由常规方法的0.86提升至新方法的0.94.     

Polymeric Multilayers that Contain Silver Nanoparticles can be Stamped onto Biological Tissues to Provide Antibacterial Activity

The design of polyelectrolyte multilayers (PEMs) that can be prefabricated on an elastomeric stamp and mechanically transferred onto biomedically‐relevant soft materials, including medical‐grade silicone elastomers (E’～450–1500 kPa; E’‐elastic modulus) and the dermis of cadaver skin (E’～200–600 kPa), is reported. Whereas initial attempts to stamp PEMs formed from poly(allylamine hydrochloride) and poly(acrylic acid) resulted in minimal transfer onto soft materials, we report that integration of micrometer‐sized beads into the PEMs (thicknesses of 6–160 nm) led to their quantitative transfer within 30 seconds of contact at a pressure of ～196 kPa. To demonstrate the utility of this approach, PEMs were impregnated with a range of loadings of silver‐nanoparticles and stamped onto the dermis of human cadaver skin (a wound‐simulant) that was subsequently incubated with bacterial cultures. Skin dermis stamped with PEMs that released 0.25 ± 0.01 μg cm^?2 of silver ions caused a 6 log₁₀ reduction in colony forming units of Staphylococcus epidermidis and Pseudomonas aeruginosa within 12 h. Significantly, this level of silver release is below that which is cytotoxic to NIH 3T3 mouse fibroblast cells. Overall, this study describes a general and facile approach for the functionalization of biomaterial surfaces without subjecting them to potentially deleterious processing conditions.     

Digital image analysis of gunshot residue dimensional dispersion by computer vision method

Detection and identification of gunshot residues (GSR) have been used as base evidence in elucidating forensic cases. GSR particles consist of burnt and partially unburned material and contaminate the hands, face, hair, and clothes of the shooter when coming out of the gun. Nowadays, GSR samples are collected from the hands of the suspect and are analyzed routinely in forensic laboratories by the scanning electron microscope/energy dispersive spectroscopy (SEM/EDS) method. GSR particles are comprised of a morphological and specific structure (generally spherical and have a diameter between 0 and 100 μm [occasionally even larger]). In addition, the present studies in the field have claimed that GSR particles during formation are formed under equilibrium surface distribution and are unrelated to morphological dimensional classification. Our contribution to this study is two-folded. First, this study offers a new approach to identify images of GSR particles by computer vision gathered by SEM/EDS method from the hand of the shooter. Second, it presents open access to the SEM/EDS image data set of the analyzed GSR. During the study, a new data set consisting of 22,408 samples from three different types of MKEK (Mechanical and Chemical Industries Corporation) brand ammunition has been used. It is seen in the results that the computer vision method has been successful in the dimensional classification of GSR.     

应用系统工程于扩大火炮射程的研究

射程为火炮主要指标之一。本文应用系统工程思想与方法,就扩大火炮射程问题进行了讨论。经分析指,出运用火箭弹以增程的方法是可取的。     

根据创口射击残留物推断"7.9"式轻型冲锋枪射击距离的研究

目的:研究枪弹射入门周围射击残留物(GsR)与射击距离的关系,探讨其能否用于射击距离的判断.方法采用"7.9"式轻型冲锋枪分别在5cm、loom、15cm、20cm、30cm、40cm、50cm、70cm、80cm、90cm、120cm、120cm处射击乳猪,用SEM/EDX观察创口周围GSR的分布和成分,建立回归方程.结果射击距离和GSR颗粒数量之间总体表现为直线关系.结论根据创口周围GSR可以判断"7.9"式轻型冲锋枪的射击距离.     

Bioinspired Intrinsic Versatile Hydrogel Fabricated by Amyloidal Toxin Simulant-Based Nanofibrous Assemblies for Accelerated Diabetic Wound Healing

Persistent microbial infection and decreased neovascularization are common issues associated with diabetic wound treatment. Hydrogel dressings that offer intrinsic antibacterial and angiogenesis-inducing may substantially avoid the use of antibiotics or angiogenic agents. Herein, a versatile hydrogel is fabricated using an amyloid-derived toxin simulant (Fmoc-LFKFFK-NH₂, FLN) as building blocks, inspired by the defense strategy of Staphylococcus aureus (S. aureus). The simulant assemblies of the hydrogel function as both matrix components and functional elements for diabetic wound treatment. The hydrogel undergoes quick assembly from random monomers to nanofibrils with abundant b-sheet driven by multiple non-covalent interactions. The developed hydrogel demonstrates excellent biocompatibility and accelerates angiogenesis via hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor A (VEGFA) signaling as a consequence of its amyloidal structure. The simulant-based nanofibrils endow the hydrogel with broad-spectrum antibacterial activity dominated by a membrane-disruption mechanism. In addition, the hydrogel exhibits excellent performance compared with the commercial hydrogel Prontosan in accelerating wound healing of diabetic mice infected with methicillin-resistant S. aureus (MRSA). This study highlights the fabrication of a single component and versatile hydrogel platform, thereby avoiding the drug-related side effects and complicated preparations and demonstrating its profound potential as a clinical dressing for the management of microbe-infected diabetic wounds.     

Biofilms in Diabetic Foot Ulcers: Impact,Risk Factors and Control Strategies

Diabetic foot ulcers (DFUs) are a serious complication from diabetes mellitus, with a huge economic, social and psychological impact on the patients’ life. One of the main reasons why DFUs are so difficult to heal is related to the presence of biofilms. Biofilms promote wound inflammation and a remarkable lack of response to host defences/treatment options, which can lead to disease progression and chronicity. In fact, appropriate treatment for the elimination of these microbial communities can prevent the disease evolution and, in some cases, even avoid more serious outcomes, such as amputation or death. However, the detection of biofilm-associated DFUs is difficult due to the lack of methods for diagnostics in clinical settings. In this review, the current knowledge on the involvement of biofilms in DFUs is discussed, as well as how the surrounding environment influences biofilm formation and regulation, along with its clinical implications. A special focus is also given to biofilm-associated DFU diagnosis and therapeutic strategies. An overview on promising alternative therapeutics is provided and an algorithm considering biofilm detection and treatment is proposed.