Ultrasonic resonator technology as a new quality control method evaluating gelatin nanoparticles

Nanomedicine is a quickly evolving field where more and more possible applications become evident and start entering clinical trials or even the market. However, the analytic methods are not always able to keep pace with the new formulations’ demands. One example of a promising medical implementation is oligodeoxynucleotide (ODN) delivery by gelatin nanoparticles (GNPs). Currently, quality control is dependent on either some time consuming or destructive spectrometric, chromatographic or electrophoretic methods. A possible enlargement of the portfolio by Ultrasonic Resonator Technology (URT) is investigated here by subjecting plain GNPs in various sizes and concentrations as well as ODN-loaded GNPs to URT analysis. If calibrated by photon correlation spectroscopy (PCS) and other spectroscopy methods for each single nanoparticle system parameter, URT is an efficient and non-destructive technique and serves as a broad characterization method. URT is emphasized to play a possible future part in the size, concentration and ODN loading monitoring, e.g. of gelatin nanoparticles in the course of formulation development.     

超高效液相色谱-三重四级杆质谱法检测阿归养血糖浆中阿胶及牛皮源成分

目的：建立阿归养血糖浆中阿胶及掺杂牛皮源成分的专属性检测方法。方法：用胰蛋白酶对阿归养血糖浆处方中胶类成分进行酶解，采用超高效液相色谱-三重四极杆质谱（UPLC-QQQ/MS），选择阿胶特征分子离子峰m/z 540.0（双电荷）→612.2、m/z 540.0（双电荷）→924.4及牛皮源特征离子对m/z 641.3（双电荷）→726.2、m/z 641.3（双电荷）→783.3作为检测离子对，离子化模式为ESI⁺，进行多反应监测。结果：26批阿归养血糖浆中未检出阿胶的有13批，其中3批检出牛皮源成分，1批检出牛皮源成分但未超出限度，9批均未检出阿胶及牛皮源成分；26批样品检出阿胶的有13批，其中同时检出牛皮源成分的有1批，未检出牛皮源成分的为12批。结论：该检测方法专属性强，可用于阿归养血糖浆中阿胶及牛皮源的检测。     

Timing of Uterine Artery Embolization for Leiomyoma during the Menstrual Cycle

PurposeTo investigate differences in outcomes of uterine artery embolization (UAE) for leiomyoma when performed during different phases of the menstrual cycle.Materials and MethodsIn this single-institution retrospective analysis, 111 premenopausal patients (median [range] age, 44 [33–52] years) undergoing UAE for symptomatic leiomyoma between June 2014 and February 2020 were included. Twenty-one patients underwent UAE in the menstrual phase (the early follicular phase), 27 in the late follicular phase, and 63 in the luteal phase. Baseline characteristics and technical and peri-procedural outcomes were compared among groups. Leiomyoma infarction on contrast-enhanced magnetic resonance imaging 1 week after UAE and 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire scores, the volume reduction rates of the uterus and largest leiomyoma, follicle stimulating hormone values, adverse events, and amenorrhea, were compared among groups.ResultsA 4-month follow-up was completed for all patients. No significant differences were observed among groups in baseline characteristics or technical and peri-procedural outcomes. There were no significant differences in the multivariate-adjusted 1-week infarction rates of all leiomyoma volumes (P = .161) or multivariate-adjusted 4-month outcomes, including changes in the Uterine Fibroid Symptom and Quality of Life questionnaire symptoms and total scores (P = .864 and P = .798, respectively), the volume reduction rates of the uterus and the largest leiomyoma (P = .865 and P = .965, respectively), and follicle stimulating hormone values (P = .186) among the groups. No significant differences were noted in the 4-month adverse events (P = .260) or amenorrhea (P = .793) among the groups.ConclusionsThe present study demonstrated no significant differences in the outcomes of UAE for leiomyoma when performed during different phases of the menstrual cycle.     

Preparation,characterization and bioactivities of nano anhydrous calcium phosphate added gelatin–chitosan scaffolds for bone tissue engineering

Abstract

Gelatin, chitosan and nano calcium phosphate based composite scaffold with tailored architectures and properties has great potential for bone regeneration. Herein, we aimed to improve the physico chemical, mechanical and osteogenic properties of 3D porous scaffold by incorporation of dihydrogen calcium phosphate anhydrous (DCPA) nanoparticles into biopolymer matrix with variation in composition in the prepared scaffolds. Scaffolds were prepared from the slurry containing gelatin, chitosan and synthesized nano DCPA particle using lyophilization technique. DCPA nano particles were synthesized using calcium carbonate and phosphoric acid in water–ethanol medium. XRD pattern showed phase pure DCPA in synthesized nanopowder. Scaffolds were prepared by addition of DCPA nanoparticles to the extent of 5–10?wt% of total polymer into gelatin–chitosan solution with solid loading varying between 2.5 and 2.75?wt%. The prepared scaffold showed interconnected porosity with pore size varying between 110 and 200 micrometer. With addition of DCPA nanoparticles, average pore size of the prepared scaffolds decreased. With increase in nano ceramic phase content from 5?wt% to 10?wt% of total polymer, the compressive strength of the scaffold increased. Scaffold containing 10?wt% DCPA showed the highest average compressive strength of 2.2?MPa. Higher cellular activities were observed in DCPA containing scaffolds as compared to pure gelatin chitosan scaffold suggesting the fact that nano DCPA addition into the scaffold promoted better osteoblast adhesion and proliferation as evident from MTT assay and scanning electron microscopic (SEM) investigation of osteoblast cultured scaffolds. A higher degree of lamellopodia and filopodia extensions and better spreading behavior of osteoblasts were observed in FESEM micrographs of MG 63 cultured DCPA containing scaffold. The results demonstrated that both mechanical strength and osteogenic properties of gelatin–chitosan scaffold could be improved by addition of anhydrous dihydrogen calcium phosphate nanoparticles into it.     

明胶微冰胶支架有利于脂肪来源间充质干细胞体外干性维持并提高其体内应用价值

目的研究人脂肪来源间充质干细胞(ADSCs)与明胶微冰胶材料体外联合培养时,材料是否能维持间充质干细胞的生物学特性。方法 ADSCs种植于明胶微冰胶材料后进行Calcein-AM和PI活细胞染色检测细胞活力,细胞滴度蓝法检测细胞增殖能力,定量PCR检测干性基因OCT4、Nanog、SOX2表达情况,以及在成脂成骨诱导过程比较ADSCs在二维环境和种植于明胶微冰胶材料后的分化潜能。结果 ADSCs在三维明胶微冰胶支架材料中能保持较高活性,增殖能力不受影响,干性基因表达上调,成脂成骨分化相关基因表达水平比二维诱导环境低。结论明胶微冰胶可以为ADSCs提供一个较二维培养更好的微环境,有利于ADSCs体外干性维持,从而在干细胞移植法治疗相关疾病时以非侵入性的细胞传递方式发挥更长期的应用价值。     

Chitosan/gelatin porous scaffolds containing hyaluronic acid and heparan sulfate for neural tissue engineering

The novel chitosan (Cs)/gelatin (Gel) porous scaffolds containing hyaluronic acid (HA) and heparan sulfate (HS) were fabricated via freeze-drying technique, and their physicochemical characteristics including pore size, porosity, water absorption, and in vitro degradation and biocompatibility were investigated. It was demonstrated that the Cs/Gel/HA/HS composite scaffolds had highly homogeneous and interconnected pores with porosity above 96% and average pore size ranging from 90 to 140?μm and a controllable degradation rate. The scanning electron microscopic images, cell viability assay, and fluorescence microscopy observation revealed that the presence of HA and HS in the scaffolds significantly promoted initial neural stem and progenitor cells (NS/PCs) adhesion and supported long-time growth in three-dimensional environment. Moreover, NS/PCs also maintained mutilineage differentiation potentials with enhanced neuronal differentiation upon induction in the Cs/Gel/HA/HS composite scaffolds in relation to Cs/Gel scaffolds. These results indicated that the Cs/Gel/HA/HS composite scaffolds were suitable for neural cells’ adhesion, survival, and growth and could offer new and important options for neural tissue engineering applications.     

In vitro evaluation of random and aligned polycaprolactone/gelatin fibers via electrospinning for bone tissue engineering

Scaffold, as an essential element of tissue engineering, should provide proper chemical and structural cues to direct tissue regeneration. In this study, aligned and random polycaprolactone (PCL)/gelatin fibrous scaffolds with different mass ratio were electrospun. Chemical, structural, and mechanical properties of PCL/gelatin fibrous scaffolds were characterized by FTIR and tensile measurements. The average diameters of different groups were between 334.96?±?41.43?nm and 363.78?±?50.49?nm. Blending PCL with gelatin increased the mechanical properties of the scaffolds. The cell culture results demonstrated that the mass ratio of PCL and gelatin showed no obvious effects on cell behavior, whereas the cell growth behavior was affected by the fibers orientation. Higher elongation ratio, enhanced cell proliferation and elevated alkaline phosphatase activity were observed for cells cultured on aligned fibers. The findings in our research provide insightful information for the design and fabrication of scaffolds for bone tissue engineering.     

Development of chitosan/gelatin hydrogels incorporation of biphasic calcium phosphate nanoparticles for bone tissue engineering

Abstract

The chitosan/gelatin hydrogel incorporated with biphasic calcium phosphate nanoparticles (BCP-NPs) as scaffold (CGB) for bone tissue engineering was reported in this article. Such nanocomposite hydrogels were fabricated by using cycled freeze-thawing method, of which physicochemical and biological properties were regulated by adjusting the weight ratio of chitosan/gelatin/BCP-NPs. The needle-like BCP-NPs were dispersed into composites uniformly, and physically cross-linked with chitosan and gelatin, which were identified via Scanning Electron Microscope (SEM) images and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The porosity, equilibrium swelling ratio, and compressive strength of CGB scaffolds were mainly influenced by the BCP-NPs concentration. In vitro degradation analysis in simulated body fluids (SBF) displayed that CGB scaffolds were degraded up to at least 30?wt% in one month. Also, CCK-8 analysis confirmed that the prepared scaffolds had a good cytocompatibility through in culturing with bone marrow mesenchymal stem cells (BMSCs). Finally, In vivo animal experiments revealed that new bone tissue was observed inside the scaffolds, and gradually increased with increasing months, when implanted CGB scaffolds into large necrotic lesions of rabbit femoral head. The above results suggested that prepared CGB nanocomposites had the potential to be applied in bone tissue engineering.     

Vascularization into a porous sponge by sustained release of basic fibroblast growth factor

Vascularization into a poly(vinyl alcohol) (PVA) sponge was investigated using basic fibroblast growth factor (bFGF). This growth factor was impregnated into biodegradable gelatin microspheres for its sustained release and then the bFGF-containing microspheres or free bFGF were incorporated into PVA sponges. Following subcutaneous implantation into the back of mice, the bFGF-containing gelatin microspheres induced vascularization in and around the sponge to a significantly greater extent than that of free bFGF from 3 days after implantation. Significant ingrowth of fibrous tissue into the sponge was also observed when bFGF-containing microspheres were added to the sponge in contrast to free bFGF. Tissue ingrowth occurred into the deeper portion of the sponge over time while it accompanied formation of new capillaries. Empty gelatin microspheres had no effect on vascularization and the level of fibrous tissue ingrowth into the sponge was similar to that of the control group. It was concluded that incorporation of gelatin microspheres containing bFGF into the PVA sponge was effective in prevascularization of the sponge pores.