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1.
Objective: Animal environments for the growth of stem cells cause the transmission of some diseases and immune problems for the recipient. Accordingly, replacing these environments with healthy environments, at least with human resources, is essential.  One of the media that can be used as an alternative to animal serums is Wharton acellular jelly (AWJ).  Therefore, in this study, we intend to replace FBS with Wharton jelly and investigate its effect on the expression of megakaryocyte-related genes and markers in stem cells. Materials and Methods: In this study, cord blood-derived CD34 positive HSCs were cultured and expanded in the presence of cytokines including SCF, TPO, and FLT3-L. Then, the culture of expanded CD34 positive HSCs was performed in two groups: 1) IMDM culture medium containing 10% FBS and 100 ng / ml thrombopoietin cytokine 2) IMDM culture medium containing 10% AWJ, 100 ng / ml thrombopoietin cytokine.  Finally, CD41 expressing cells were analyzed with the flow cytometry method. The genes related to megakaryocyte lineage including FLI1 and GATA2 were also evaluated using the RT-PCR technique.  Results: The expression of CD41, a specific marker of megakaryocyte lineage in culture medium containing Wharton acellular jelly was increased compared to the FBS group. Additionally, the expression of GATA2 and FLI1 genes was significantly increased related to the control group. Conclusion: This study provided evidence of differentiation of CD34 positive hematopoietic stem cells from umbilical cord blood to megakaryocytes in a culture medium containing AWJ.  相似文献   
2.
Abstract

Wharton’s Jelly (WJ) tissue is a promising biomaterial, for tissue engineering applications. However, its preservation over a long period in order to be readily available needs further optimization. A possible solution could be the vitrification and storage of WJ tissue at low temperatures. The aim of this study is to evaluate the effect of low temperature in the WJ tissue, which was stored at ?196?°C, either with the vitrification or conventional cryopreservation methods. WJ tissues were isolated from human umbilical cords, cryopreserved with the above methods and remained for 1?year at ?196?°C. Histological analysis of tissue’s extracellular matrix (ECM), isolation, and characterization of mesenchymal stromal cells (MSCs) were performed. Histological analysis revealed the presence of ECM components such as collagen, sulfated glycosaminoglycans (sGAGs), and the presence of cell nuclei only in vitrified samples. Furthermore, MSCs were isolated and expanded successfully from vitrified WJ tissues, whereas a few viable cells were obtained from conventionally cryopreserved tissues that were not further expanded. In conclusion, this study indicated the proper preservation of vitrified WJ tissues after 1?year of storage, which eventually could be used in tissue engineering and regenerative medicine approaches.  相似文献   
3.
《Saudi Pharmaceutical Journal》2022,30(10):1435-1447
Etilefrine hydrochloride (ET) is a water-soluble drug that is used to treat hypotension, but it has a bitter taste and low bioavailability due to undergoing the first-pass effect. Thus, this study aimed to develop and evaluate oral medicated jelly (OMJ) containing ET that could offer an easily taken palatable dosage form with higher bioavailability. OMJ is a novel palatable drug delivery system that can easily be taken by pediatric and geriatric patients, as well as those with dysphagia. Moreover, OMJs offer rapid disintegration in saliva and rapid drug absorption through the buccal mucosa, avoiding the first-pass effect and increasing the drug bioavailability. Natural polymers such as pectin, guar gum, xanthan gum, tragacanth gum, and sodium alginate were used as jellifying agents, with the addition of calcium chloride as a crosslinking agent, to prepare OMJs using the heat and congealing method. The prepared OMJs were investigated by testing their viscosity, in vitro release, and texture analysis of firmness, consistency, stickiness, cohesiveness, springiness, gumminess, and chewiness using a texture analyzer. A full factorial design (21 × 51) was utilized to select the optimized OMJ. The optimized OMJ (J2), containing 4 % pectin, had a 7563 ± 55 cps viscosity, 8.32 ± 0.21 N firmness, 5.72 ± 0.18 µJ consistency, 1.30 ± 0.04 mJ stickiness, and 96.02 ± 3.74 % ET dissolved after 10 min. ET release was significantly increased (greater than4-fold) from the optimized OMJ compared with the market tablet. Moreover, the obtained results clarified the stability and the acceptable palatability of the optimized OMJ. The clinical investigation on healthy human volunteers revealed that the optimized OMJ (J2) had significantly higher Cmax (1.7 folds) when compared with the market tablet with a relative bioavailability of 154.55 %. Therefore, OMJs can be considered as promising, palatable, and easily swallowed dosage form that could enhance the bioavailability of drugs undergoing the first-pass effect.  相似文献   
4.
目的:将脐带华通胶间充质干细胞(WJMSCs)移植到子宫切口瘢痕缺陷(PCSD)模型大鼠体内,探讨其治疗效果。方法:取雌性SD大鼠50只、将其随机分为3组:正常手术组(N-O组)10只、模型对照组(M-C组)20只和模型治疗组(M-T组)20只。孕第19天N-O组剖宫取胎后连续缝合子宫切口;M-C组与M-T组剖宫产术后子宫肌壁注射脂多糖(LPS)联合电凝(功率为10 W)子宫切缘,间断缝合切口。M-T组分A、B亚组(各10只),A组静脉注射0.5 m L+阴道灌注0.5 m L(1×10~9/L)WJMSCs,B组阴道灌注1 m L同浓度WJMSCs,每周1次,共3次;M-C亦分A、B亚组(各10只),与M-T组同样方法处理,仅将生理盐水替代WJMSCs。各组治疗后第1和4周,分别处死6和4只,留双侧子宫进行HE染色、Masson染色、肌动蛋白(actin)和细胞角蛋白免疫组化染色,通过体视学分析,检测子宫肌层和内膜的修复情况。结果:WJMSCs治疗后第1和4周,M-C组子宫肌层厚度和actin体积密度(Vv)均显著低于N-O组,肌层胶原纤维Vv和内膜缺陷率高于N-O组(P0.05);WJMSCs治疗后第1和4周,M-T的A和B组的肌层厚度和actin Vv均显著高于M-C组,肌层胶原纤维Vv低于M-C组;M-C组内膜缺陷率高于其它组(P0.05)。结论:WJMSCs可促进PCSD大鼠子宫肌层结构和功能的修复。静脉+局部联合治疗和单纯阴道治疗效果无明显差别。  相似文献   
5.
6.
目的探讨两种麻醉方式在绝经后妇女宫内节育器(intrauterine contraceptive device,IUD)取出术中的临床疗效。方法将要求取IUD的240例绝经后妇女按不同麻醉方式分为3组:盐酸丁卡因胶浆组(A组);丙泊酚组(B组);不用药物对照组(C组),每组各80例。结果 A、B组与C组比较,镇痛效果、手术成功率差异均有统计学意义(P<0.05),B组的镇痛效果、困难取IUD、取器失败率明显优于A组(P<0.05)。结论在取IUD过程中根据绝经后妇女自身特点采取一定的措施,可改善宫颈条件,避免不必要的损伤,减轻患者痛苦,提高取IUD成功率。  相似文献   
7.
Objective: The aim of the study was to compare the neuroglial phenotype of Wharton's jelly-derived mesenchymal stem cells (WJ-MSC) from pregnancies complicated with preeclampsia and gestational age (GA)-matched controls.

Methods: WJ-MSC were isolated from umbilical cords from both groups and analyzed for the cell surface expression of MSC markers and the gene and protein expression of neuroglial markers.

Results: All WJ cells were highly positive for the MSC markers CD105, CD90 and CD73, but negative for markers specific for hematopoietic (CD34) and immunological cells (CD45, CD14, CD19 and HLA-DR). WJ-MSC from both groups expressed neuroglial markers (MAP-2, GFAP, MBP, Musashi-1 and Nestin) at the mRNA and protein level. The protein expressions of neuronal (MAP-2) and oligodendrocytic (MBP) markers were significantly increased in WJ-MSC from preeclampsia versus GA-matched controls.

Conclusions: WJ-MSC from preeclamptic patients are possibly more committed to neuroglial differentiation through the activation of pathways involved both in the pathophysiology of the disease and in neurogenesis.  相似文献   

8.
Alginate scaffold has been considered as an appropriate biomaterial for promoting the differentiation of embryonic stem cells toward neuronal cell lineage. We hypothesized that alginate scaffold is suitable for culturing Wharton's jelly mesenchymal stem cells(WJMSCs) and can promote the differentiation of WJMSCs into neuron-like cells. In this study, we cultured WJMSCs in a three-dimensional scaffold fabricated by 0.25% alginate and 50 m M Ca Cl2 in the presence of neurogenic medium containing 10 μM retinoic acid and 20 ng/m L basic fibroblast growth factor. These cells were also cultured in conventional two-dimensional culture condition in the presence of neurogenic medium as controls. After 10 days, immunofluorescence staining was performed for detecting β-tubulin(marker for WJMSCs-differentiated neuron) and CD271(motor neuron marker). β-Tubulin and CD271 expression levels were significantly greater in the WJMSCs cultured in the three-dimensional alginate scaffold than in the conventional two-dimensional culture condition. These findings suggest that three-dimensional alginate scaffold cell culture system can induce neuronal differentiation of WJMSCs effectively.  相似文献   
9.
10.
目的 了解郑州市凉粉类淀粉制品中微生物污染状况,为预防食源性疾病提供依据。 方法 根据GB 4789.2-2010、GB 4789.3-2010、GB 4789.4-2010以及GB 4789.10-2010对凉粉类淀粉制品中菌落总数、大肠菌群、沙门氏菌以及金黄色葡萄球菌分别进行检测。 结果 按照GB 2713-2003《淀粉制品卫生标准》要求判断,260份样品菌落总数合格率为23.08%,大肠菌群检出率为75.00%;样品间菌落总数存在差异(P<0.01),大肠菌群含量差异也较大。沙门氏菌检出率为11.54%,金黄色葡萄球菌检出率为3.85%。 结论 郑州市凉粉类淀粉制品微生物污染问题较为普遍,应加强对该类食品的监管,以改善该类食品的卫生状况。  相似文献   
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