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1.
Jinrui Li Feng Gao Shanshan Ma Yanting Zhang Junni Zhang Fangxia Guan Minghao Yao 《Journal of tissue engineering and regenerative medicine》2020,14(9):1261-1271
Stem‐cell‐based therapy is a promising strategy to treat challenging neurological diseases, while its application is hindered primarily by the low viability and uncontrolled differentiation of stem cell. Hydrogel can be properly engineered to share similar characteristics with the target tissue, thus promoting cell viability and directing cell differentiation. In this study, we proposed a new dual‐enzymatically cross‐linked and injectable gelatin hydrogel for regulating survival, proliferation, and differentiation of human umbilical cord mesenchymal stem cells (hUC‐MSCs) in a three‐dimensional matrix. This injectable gelatin hydrogel was formed by oxidative coupling of gelatin–hydroxyphenyl acid conjugates catalyzed by hydrogen horseradish peroxidase (HRP) and choline oxidase (ChOx). Modulus and H2O2 release can be well controlled by ChOx activity. Results from calcein‐AM/PI staining and Ki67 immunofluorescence tests demonstrated that the survival and proliferation behavior of hUC‐MSCs were highly enhanced in HRP1UChOx0.25U hydrogel with lower modulus and less H2O2 release compared with other groups. Attractively, the expression of neuron‐specific markers β‐III tubulin, neurofilament light chain (NFL), and synapsin‐1 was significantly increased in HRP1UChOx0.25U hydrogel as well. Additionally, in vitro hemolysis test and in vivo HE staining data highlighted the good biocompatibility. Undoubtedly, this injectable gelatin hydrogel's ability to control hUC‐MSCs' fate holds enormous potentials in nervous disorders' therapy and nerve regeneration. 相似文献
2.
Bernhard Wagner Thomas Brinz Johannes Khinast 《Pharmaceutical development and technology》2019,24(6):775-787
This paper addresses the relevance of automated content testing for the rapid automated process development (RAPD). Our previous work demonstrated that RAPD allowed a fast and efficient development of a continuous capsule-filling process. Target was the mean weight and the relative standard deviation of the weight. Likewise important are the content and the content uniformity. However, an implementation demands a certain level of automation. In general, technology is available that can detect active pharmaceutical ingredient (API) inside the capsules but the final application is linked to additional development and investment in machinery. To eliminate doubts regarding the benefits of an automated content check within the RAPD we present an application example. First, an X-ray system was used to detect barium sulfate accurately inside capsules. Second, a process was developed where barium sulfate was filled. The concentration of excipients was modified in the experiments, as well as the setting of the process parameter. The obtained model provided an explicit understanding of the process. Subsequently, the content uniformity model was compared to a model of the capsule weight relative standard deviation, confirming the benefits of an automated content check in the RAPD. Moreover, we presented another example illustrating the advantages of a connected continuous filling process, which permits evaluation of all process steps and their interactions (i.e. evaluation of the entire process). 相似文献
3.
Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle
《Journal of vascular and interventional radiology : JVIR》2020,31(12):2132-2140.e5
PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent. 相似文献
4.
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。 相似文献
5.
Tetsuya Katsumori Tatsuya Yoshikawa Yasuteru Sasakura Toshinori Yasumura Mitsuhiro Hisano 《Journal of vascular and interventional radiology : JVIR》2021,32(3):332-338
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. 相似文献
6.
Alexander Lisov Veronika Vrublevskaya Zoy Lisova Alexey Leontievsky Oleg Morenkov 《Viruses》2015,7(10):5343-5360
Various natural and synthetic polyanionic polymers with different chemical structures are known to exhibit potent antiviral activity in vitro toward a variety of enveloped viruses and may be considered as promising therapeutic agents. A water-soluble conjugate of 2,5-dihydroxybezoic acid (2,5-DHBA) with gelatin was synthesized by laccase-catalyzed oxidation of 2,5-DHBA in the presence of gelatin, and its antiviral activity against pseudorabies virus (PRV) and bovine herpesvirus type 1 (BoHV-1), two members of the Alphaherpesvirinae subfamily, was studied. The conjugate produced no direct cytotoxic effect on cells, and did not inhibit cell growth at concentrations up to 1000 µg/mL. It exhibited potent antiviral activity against PRV (IC50, 1.5–15 µg/mL for different virus strains) and BoHV-1 (IC50, 0.5–0.7 µg/mL). When present during virus adsorption, the conjugate strongly inhibited the attachment of PRV and BoHV-1 to cells. The 2,5-DHBA–gelatin conjugate had no direct virucidal effect on the viruses and did not influence their penetration into cells, cell-to-cell spread, production of infectious virus particles in cells, and expression of PRV glycoproteins E and B. The results indicated that the 2,5-DHBA–gelatin conjugate strongly inhibits the adsorption of alphaherpesviruses to cells and can be a promising synthetic polymer for the development of antiviral formulations against alphaherpesvirus infections. 相似文献
7.
可吸收止血流体明胶预防术后脑脊液漏 总被引:2,自引:2,他引:0
目的:探索可吸收止血流体明胶预防术后脑脊液漏的有效性。方法:对2013年3月至9月有硬脊膜撕裂脑脊液漏的脊柱损伤17例患者进行回顾性分析,男16例,女1例;年龄16~67岁,平均(39.6±15.4)岁;颈椎1例,胸椎9例,胸腰段4例,腰椎3例;爆裂骨折4例,骨折脱位13例。神经损伤ASIA分级:A级12例,B级2例,D级2例,E级1例。车祸伤2例,高处坠落伤10例,重物砸伤4例,地震时从楼梯滚落1例。术中应用可吸收止血流体明胶封堵以预防术后脑脊液漏。记录术后每日的引流量。结果:17例患者有15例术后无脑脊液漏出现。2例术后出现脑脊液漏者引流管保留至术后第6~7天。术后未出现头痛、头晕、发热、颈项抵抗、皮疹、切口不愈合、切口感染、血肿、神经症状加重等并发症。随访9个月均未见到切口周围有异常现象。结论:术中应用可吸收止血流体明胶封堵硬脊膜撕裂预防术后脑脊液漏是有效的方法。 相似文献
8.
盐酸米诺环素复合明胶海绵治疗干槽症的临床研究 总被引:1,自引:0,他引:1
目的:比较盐酸米诺环素复合明胶海绵与碘仿纱条治疗干槽症的疗效。方法:58例确诊为干槽症的患者经常规清创后,随机均分为2组。实验组牙槽窝内置入盐酸米诺环素复合明胶海绵;对照组填塞碘仿纱条,随访比较其疗效。结果:组间比较[实验组/对照组:优(例)23/16;良(例)6/11;可(例)0/2],Kruskal-Wallis检验法检验,疗效评价等级为"优"的实验组病例数多于对照组(P<0.05)。结论:盐酸米诺环素复合明胶海绵对干槽症的疗效优于碘仿纱条。 相似文献
9.
Takahashi D Odajima T Morita M Kawanami M Kato H 《Journal of periodontal research》2005,40(4):299-305
OBJECTIVES: Periodontal regeneration under application of bone morphogenetic protein (BMP) is compromised by ankylosis. Ankylosis disappearance following application of BMP has been observed in the case of a small defect, which might be beneficial change for periodontal regeneration. However, the histological observation of ankylosis disappearance has not been demonstrated in a large defect. The purpose of this present study was to confirm resolution of ankylosis during periodontal regeneration by recombinant human BMP-2 (rhBMP-2) applied to class III furcation defects. MATERIAL AND METHODS: Class III furcation defects were created in the premolars of six adult cats. The rhBMP-2 material, prepared by applying rhBMP-2 to a combination of polylactic acid-polygricolic copolymer and gelatin sponge (PGS; 0.33 microg rhBMP-2/mm(3) PGS) or control material containing only PGS, was implanted into each defect. The cats were killed at 3, 6 or 12 weeks after surgery and serial sections were prepared for histological and histometrical observation. RESULTS: Ankylosis was observed in some of the rhBMP-2/PGS group at 3 and 6 weeks, but not at 12 weeks. At 6 weeks, osteoclast-like cells were visible in the rhBMP-2/PGS group with ankylosis. Residual PGS was evident between the bone and root surface in the rhBMP-2/PGS group without ankylosis at 3 weeks. CONCLUSIONS: Resolution of ankylosis by osteoclast-like cells possibly occurred under application of rhBMP-2. Residual PGS might play an important role in preventing ankylosis formation. 相似文献
10.
纪志农 《现代口腔医学杂志》2007,21(2):153-155
目的 探讨术前急性高容量血液稀释对正颌外科病人血液动力学和凝血功能的影响,评估该方法临床应用的价值。方法 选择择期行正颌外科双颔手术的病人40例,随机分为ABCD四组,每组10例。A为贺斯实验组。术前输注6%羟乙基淀粉和乳酸林格液各占总量1/2,行急性高容血液稀释;B为贺斯对照组,用6%羟乙基淀粉和乳酸林格液补充术中丢失血液和体液;C为佳乐施实验组,术前输注4%琥珀酰明胶和乳酸林格液各占总量1/2,行急性高容血液稀释;D为佳乐施对照组,用4%琥珀酰明胶和乳酸林格液补充术中丢失血液和体液。四组病例术中均采用硝普钠控制性降压,平均动脉压(MAP)控制在50~60mmHg。实验组在插管后稀释前即刘(T0),稀释后手术开始前即刻(T1),手术结束即刻(T2),术后第一日8AM(T3)时;对照组在手术开始前即刻(T1),手术结束即刘(T2),术后第一日8AM(T3)时,记录RBC、HBG、HCT及凝血指标的变化,以及血液动力学的变化。结果 MAP:A、C组T1低于T0(P〈0.01);T2高于T1(P〈0.01)。HR:A、C组T2高于T0、T1(P〈0.01)。RBC、HGB、HCT和PLT:A、C组T1低于T0(P〈0.01),T3升高超过T1且接近T0。结论 术前急性高容量血液稀释对正颌外科病人血液动力学的稳定影响小,能减少血液的丢失。贺斯与佳乐施两种胶体液均可引起部分凝血指标的改变,但二者均不影响凝血功能。可以作为正颌外科手术选择性应用的一种有效的辅助方法。 相似文献