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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.
蜂王浆冻干粉对小鼠肿瘤的抑制作用   总被引:4,自引:0,他引:4  
目的研究蜂王浆冻干粉对小鼠肿瘤的抑制作用.方法按每公斤体重0g、0.25g、0.50g、0.75g设对照及低、中、高3个剂量组,经口给予蜂王浆冻干粉30d后,接种小鼠肉瘤180(S180)和艾氏癌腹水型(EAC)两个瘤种.结果在两次重复的小鼠S180和EAC抑瘤试验中发现中剂量组瘤重明显低于阴性对照组(P<0.05),抑制率可达34%;中剂量组荷瘤小鼠平均生存时间均明显高于对照组(P<0.05).结论蜂王浆冻干粉具有抑制肿瘤的作用.  相似文献   
3.
Neonatal diseases such as hypoxic ischemic encephalopathy, diseases of prematurity and congenital disorders carry increased morbidity and mortality. Despite technological advancements, their incidence remains largely unabated. Stem cell (SC) interventions are novel therapies in the neonatal world. In pre-clinical models of neonatal diseases, SC applications have shown encouraging results. SC sources vary, with the bone marrow being the most utilized. However, the ability to harvest bone marrow SCs from neonates is limited. Placental-tissue derived SCs (PTSCs), provide an alternative and highly attractive source. Human placentas, the cornerstone of fetal survival, are abundant with such cells. Comparing to adult pools, PTSCs exhibit increased potency, decreased immunogenicity and stronger anti-inflammatory effects. Several types of PTSCs have been identified, with mesenchymal stem cells being the most utilized population. This review will focus on PTSCs and their pre-clinical and clinical applications in neonatology.  相似文献   
4.
5.
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   

6.
Nucleotides are composed of nitrogen bases, ribose units and phosphate groups. Adenine (Ade), adenosine monophosphate (AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP) all play important roles in physiological metabolism. Royal jelly, a secretion produced by worker bees, contains a variety of natural ingredients and several studies have shown that royal jelly can serve as a source of nutrition for humans. In this study, a rapid and effective LC/ MS method coupled with pre-processing methods was developed and validated for the accurate quantification of Ade, AMP, ADP and ATP in royal jelly. To achieve the best extraction efficiency, two pretreatment methods, namely, solid-phase extraction (SPE) and dispersive solid-phase extraction (dSPE), were developed and investigated. Silica-based cyanopropyl (CN) liquid chromatography was employed using pH programming with a quaternary mobile phase system for the analyses. The total LC/MS run time was less than 12 min with a constant flow rate of 0.25 mL/min. The linear range were 2.5–1000 ng/mL with a correlation coefficient r = 0.9995. The limit of detection (LOD) of Ade, AMP, ADP and ATP was 1, 1, 2.5 and 5 ng/mL; the limit of quantitation (LOQ) was 2.5, 2.5, 5 and 10 ng/mL, respectively. Precision (RSD% <10.5%) and accuracy (recovery 81.3–118.4%) were satisfactory for both two pre-processing methods. Nucleotides were successfully quantified from 2-day and 3-day royal jelly samples, with concentrations within 6.2–2126.0 mg/kg.  相似文献   
7.
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   
8.
Objective:To investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric medicine.Methods:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant extract.For the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),orally.This w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or non-mortality.Incision wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under anesthesia.The first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,respectively.Results:The percentage yield of the extract was 49.80%w/w dry matter.The phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,perpenoids.saponins,steroids,proteins,and carbohydrates.The LD_(50) was beyond our experimental limit and was not determined.Increased concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,P0.05) healing effect on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:These data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine.  相似文献   
9.
目的:研究蜂王浆冻干粉对免疫力低下患者免疫球蛋白IgG、IgA、IgM以及补体C3、C4水平的影响,评价蜂王浆冻干粉治疗免疫力低下综合征的临床疗效。方法采用自身对照临床研究,予确诊的32例免疫力低下患者服用蜂王浆冻干粉,每天2次,1次2粒。于服药28 d后检测患者免疫球蛋白IgG、IgA、IgM和补体C3、C4等指标,并测定AST、ALT水平,评价蜂王浆冻干粉的疗效和安全性。结果服药后患者IgG、IgA、IgM水平[(10.31±2.03)g/L,(1.69±0.55)g/L,(1.51±0.55)g/L]显著高于服药前[(8.52±1.94)g/L,(1.38±0.57)g/L,(1.36±0.55)g/L](t=5.21、2.25、1.56,均P<0.05);服药后患者血清补体C3、C4水平[(0.93±0.15)g/L,(0.30±0.07)g/L]显著高于服药前[(0.83±0.12)g/L,(0.26±0.08)g/L](t=1.94、1.78,均P<0.05);服药后AST、ALT水平[(36.13±11.47)U/L,(31.83±12.36)U/L]与服药前[(38.17±12.84)U/L,(32.63±12.81)U/L]差异无统计学意义(t=0.82、0.44,均P>0.05)。结论蜂王浆冻干粉通过提高免疫力低下患者免疫球蛋白IgG、IgA、IgM和补体C3、C4,继而改善患者免疫力低下症状。  相似文献   
10.
Bee products including propolis, bee wax, pollen and royal jelly (RJ) have been used as medicine from ancient times. A vast number of in-vivo and in-vitro studies as well as clinical trials have been conducted to investigate potential health related properties of RJ. A growing number of clinical trials have been performed to assess effects of RJ ingestion on different metabolic markers including glycemia, with diverse results. In the current meataanalysis, we aimed to evaluate effects of RJ ingestion on glycemic markers compared with placebo and set directions for future research. Electronic databases including Scopus, Pubmed, Scholar, Cochrane, Proquest, SID and Magiran were searched and 5 eligible studies were included in the quantitative analysis. Review Manager Software was used for statistical analysis and random effects model was used for pooling data. A total of 205 participants for FPG and 130 participants for HbA1c were included. The overall analysis revealed that RJ consumption reduced FPG by 0.95 mg/dl (95% CI: −5.83 to 3.87; p = 0.69; I2 = 0%; Tau2 = 0.00) and HbA1c by 0.32 (95% CI: −0.87 to 0.23; p = 0.25; I2 = 69 %; Tau2 = 0.16) which were not statistically significant. Funnel plot demonstrated no publication bias. In conclusion, RJ supplementation did not beneficially affect markers of glycemia. However, due to methodology issues and potential confounders like diet as well as diverse populations, we recommend future studies well designed and well controlled for major confounders so we can update these data to more precise results and more accurate conclusion.  相似文献   
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