单唾液酸四己糖神经节苷脂联合复方丹参对极低出生体重儿神经系统预后的影响

目的单唾液酸四己糖神经节苷脂（GMI）与复方丹参对极低出生体重儿神经系统预后的影响。方法108例极低出生体重儿分为两组：在治疗原发病和早产儿各项并发症的基础上,治疗组在生后3天给予GM1（20mg／d）和复方丹参注射液（2ml／d）,对照组给予复方丹参注射液（2ml／d）,均连用14天为一个疗程。纠正胎龄37周后两组NBNA评分进行比较。结果纠正胎龄足月后治疗组NBNA评分明显高于不用GM1的对照组（P〈0．01）。结论GM1联用复方丹参在改善极低出生体重儿神经系统预后方面有较好的疗效。     

单唾液酸四己糖神经节苷脂(GM1)作为T细胞活化标志的探讨

目的:比较、分析单唾液酸四己糖神经节苷脂(GM1)和CD69分子在人外周血γδT和CD3 T细胞上的表达规律。方法:用抗CD3单克隆抗体(mAb)和结核杆菌抗原(MtbAg)等刺激剂分别刺激人外周血单个核细胞(PBMC),部分实验组同时使用信号转导途径阻断剂处理。用流式细胞术检测不同时相γδT和CD3 T细胞上GM1和CD69分子的表达率。结果:MtbAg刺激PBMC后0.5h,γδT细胞上即表达GM1,随着时间的推移表达水平持续升高;而CD69的表达出现在刺激后的3h,于24h达高峰,然后逐渐下降,72h明显降低,6d时已接近静止状态。抗CD3mAb刺激的CD3 T细胞上,GM1和CD69表达的规律类似于γδT细胞。PD98059和LY294002均能够阻断MtbAg刺激所致的γδT细胞上GM1的表达,PMA能够促进GM1的表达。结论:GM1可作为一种新的T细胞活化的标志,其与早期短暂表达的CD69分子有不同的表达规律。GM1的表达可能与RasErk通路、PI3K和PKC有关。     

单唾液酸四己糖神经节苷脂治疗新生儿缺氧缺血性脑病疗效观察

目的观察单唾液酸四己糖神经节苷脂（GM1）与胞二磷胆碱治疗新生儿缺氧缺血性脑病（HIE）的疗效比较。方法将HIE患儿40例分为GM1治疗组（n=20）和对照组（n=20）．新生儿期采用NBNA评分,随访至1a时采用Gesell量表法对其进行发育评价。结果两组在新生几期NBNA评分上差异有统计学意义（p〈0．05）,随访期Gesell量表法测定在精细运动和语言方面差异有统计学意义（P〈0．01）。结论早期应用GMI治疗新生儿HIE对急性期恢复及改善远期神经系统发育障碍有较好的疗效．     

单唾液酸神经节苷脂（GM1）对经MPTP破坏的小鼠黑质纹状体多巴胺…

将１－甲基－４苯基－１．２．３．６四氢吡啶经腹腔注入小鼠，连续注射６天，一组动物注射后次日处死。另一组动物存活二周后处死；第三组动物在给予１－甲基－４苯基－１．２．３．６四氢吡啶的同时，经腹膜腔注射神经节苷脂持续三周；第四组为对照组。各组动物脑用酶氨酸羟化酶抗体进行免疫组化观察。     

联合应用神经生长因子和神经节苷脂1对坐骨神经损伤大鼠脊髓神经元的保护作用

目的：了解联合应用神经生长因子(NGF)和神经节苷脂1(GMl)对大鼠周围神经损伤后脊髓神经元的保护作用。方法：选用SD大鼠,分为生理盐水(NS)组、NGF组、GM1组和NGF GM1组,将大鼠坐骨神经造成5mm缺损,术中硅胶管内局部加药、术后大鼠损伤侧小腿肌注药物。术后定期光、电镜观察L4～I6脊髓前角神经元结构变化,测定损伤远段和近段神经传导速度。结果：脊髓运动神经元数目以及神经传导速度4周时,NGF组和GM1组均多于或快于NS组,NGF GM1组则多于或快于NS组、NGF组和GM1组,8周时NGF GM1组、NGF组、GM1组组间无显著性差异但均多于或快于NS组。结论：NGF GM1对周围神经损伤后脊髓运动神经元退变的保护作用与单用NGF或GM1相比,能更早期地发挥作用,并且效果优于单用NGF或GM1。     

甲基-β-环糊精对T细胞膜分子CD69和GM1表达的影响

目的：探讨甲基-β-环糊精（Methyl-β-eyclodextfin，MβCD）去除细胞膜胆固醇诱导人外周血T细胞CD69和单唾液酸四己糖神经节苷脂（GangliosideGMl，GMl）的表达及机理。方法：用高浓度MβCD（10mmol／L）处理PBMC，或预先加阻断剂PD98059或／和LY294002，用流式细胞术检测T细胞GMl及CD69的表达；免疫印迹法检测MβCD诱导的CD3^＋T细胞中ZAP-70的磷酸化。结果：MβCD（10mmol／L）处理PBMC30分钟，GMl在T细胞上即有高水平表达（〉90％），CD69于处理后2小时高水平表达（〉80％）；预先加入PD98059或LY294002均能够大部分阻断MβCD诱导的T细胞CIM9表达，部分阻断GMl表达，联合应用两种抑制剂也不能完全阻断GMl的表达；MβCD能够促进CD3^＋T细胞中ZAP-70分子的酪氨酸磷酸化。结论：MβCD能够促进T细胞GMl及CD69的表达；且这两种分子的表达可能与信号分子ZAP-70、MEK／ERK及PBK有关。     

NGF和GM1联合应用对去细胞异种神经支架移植后神经再生和修复的影响

为了探讨神经生长因子(NGF)和单唾液酸四己糖神经节苷脂(GM1)联合应用对去细胞异种神经支架移植后神经再生及功能恢复的影响,本研究将SD大鼠随机分为生理盐水对照组、NGF治疗组、GM1治疗组、NGF+GM1联合治疗组,选取兔胫神经进行化学萃取,形成去细胞异种神经支架桥接大鼠10mm坐骨神经缺损,移植前分别用等渗盐水(NS)、NGF液、GM1液或NGF+GM1液浸泡去细胞异种神经支架,术后各组大鼠术侧小腿肌内分别注射NS液、NGF液、GM1液或NGF+GM1液。术后4、8周行大体观察并用神经电生理、肌湿重、免疫组织化学等方法测定神经纤维再生及功能恢复情况。结果显示:在同一时间点,NGF+GM1联合治疗组坐骨神经运动传导速度恢复率、小腿腓肠肌复合动作电位波幅恢复率、小腿三头肌湿重恢复率均优于单独用药组(P<0.05);免疫组织化学结果显示NGF+GM1联合治疗组有大量再生有髓神经纤维顺畅地通过远端吻合口。本研究结果提示联合应用NGF和GM1可明显促进去细胞异种神经支架移植后的神经纤维再生与功能恢复。     

补阳还五汤和GM1对去细胞异种神经支架移植后神经再生和修复的实验研究

目的:探讨补阳还五汤对异种去细胞神经支架移植后神经再生及功能恢复的影响以及与GM1(monosialotetrahexosy 1 gangliosides)的效果比较.方法:36只健康成年SD大鼠随机分为3组:补阳还五汤(BYHWD)治疗组、GM1治疗组和生理盐水(NS)对照组.动物分别存活4、8周,不同时段各组为6只...     

Monosialotetrahexosyl ganglioside at an optimal concentration: Inducing neuron-like differentiation of human umbilical cord mesenchymal stem cells北大核心

BACKGROUND: Studies have confirmed that monosialotetrahexosyl ganglioside can induce human umbilical cord mesenchymal stem cells to differentiate into neuron-like cells, but little is reported on its optimal concentration. OBJECTIVE: To explore the optimal concentration of monosialotetrahexosyl ganglioside that induces human umbilical cord mesenchymal stem cells to differentiate into neuron-like cells in vitro. METHODS: Human umbilical cord mesenchymal stem cells were isolated by using collagenase digestion method, and after expansion, passage 3 cells were randomly allocated into five groups. When 70%-80% of cells were confluent, 50, 100, 150 and 200 mg/L monosialotetrahexosyl ganglioside induction solutions were added in corresponding experimental groups, while cells in the blank control group were cultured in the same volume of L-DMEM medium. Cell morphology was observed under inverted phase contrast microscope. Expression levels of microtubule-associated protein 2, neurofilament protein and glial fibrillar acidic protein were measured by using immunohistochemistry ot 6 hours ofter induction. RESULTS AND CONCLUSION: Human umbilical cord mesenchymal stem cells were isolated successfully and sub-cultured stably. These cells could express surface markers of mesenchymal stem cells. Monosialotetrahexosyl ganglioside at the optimal concentration of 150 mg/L was confirmed to induce the neuron-like differentiation of human umbilical cord mesenchymal stem cells, and differentiated cells could express microtubule-associated protein 2 and neurofilament protein as neuron-specific markers. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.     

Synthesis and biological evaluation of novel structure-related hGHRH agonistic analogs

Abstract

Activity and half-life play key roles in the application of GHRH analogues. The GHRH monomers produced in a solid synthesizer were incubated, respectively, in NH₄OH solution and lyophilized to obtain their dimers. The activities, specificities, and receptor affinities of the GHRH dimers were evaluated in rGH release/inhibition, rACTH/LH/PRL release, pituitary homogenate binding, and fluorescent staining. Compared to hGHRH(1-44)NH₂ (S), PP-hGHRH(1-44)-GGC-CGG-hGHRH(44-1)-PP (2D), P-hGHRH(1-44)-GGC-CGG-hGHRH(44-1)-P (2E), ¹P-hGHRH(2-44)-GGC-CGG-hGHRH(44-2)-¹P (2F), or hGHRH(1-44)-GGC-CGG-hGHRH(44-1) (2Y) had potency of 104?±?16.7%, 94?±?32.6%, 114?±?16.6%, or 122?±?14.5% and similar specificities. The inhibition effect of GHIH on rGH stimulated by GHRH dimer was in dose-/time-dependent manner. The staining of FITC-labeled dimer showed cytomembrane distribution and the binding ranking was 2F>2D>2Y>2E>S. 2F presents the strongest activity and the highest affinity to pituitary cells. The dimer with ¹Pro-GHRH stimulates stronger rGH release than that with ¹Tyr-GHRH and the N-terminal single cyclic amino acid is required for the stimulation.     

B cells and Autoimmunity 2013

The beginning stages of liver damage induced by various etiologies (i.e. high fat diet, alcohol consumption, toxin exposure) are characterized by abnormal accumulation of lipid in liver. Alterations in intracellular lipid transport, storage, and metabolism accompanied by cellular insult within the liver play an important role in the pathogenesis of liver disease, often involving a sustained inflammatory response. The intracellular lipid transporter, fatty acid binding protein 5 (FABP₅), is highly expressed in macrophages and may play an important role in the hepatic inflammatory response after endotoxin exposure in mice. This study tested the hypothesis that FABP₅ regulates macrophage response to LPS in male C57bl/6 (wild type) and FABP₅ knockout mice, both in vitro and in vivo. Treatment with LPS revealed that loss of FABP₅ enhances the number of hepatic F4/80⁺ macrophages in the liver despite limited liver injury. Conversely, FABP₅ knock out mice display higher mRNA levels of anti-inflammatory cytokines IL-10, arginase, YM-1, and Fizz-1 in liver compared to wild type mice. Bone marrow derived macrophages stimulated with inflammatory (LPS and IFN-γ) or anti-inflammatory (IL-4) mediators also showed significantly higher expression of anti-inflammatory/regulatory factors. These findings reveal a regulatory role of FABP₅ in the acute inflammatory response to LPS-induced liver injury, which is consistent with the principle finding that FABP₅ is a regulator of macrophage phenotype. Specifically, these findings demonstrate that loss of FABP₅ promotes a more anti-inflammatory response.     

Physiological mechanisms of signal termination in biological systems

Studies on the regulation of cellular activity mainly focus on signal generation, but termination of signalling is an equally important factor, which prevents inappropriate activity. This paper reviews the mechanisms, which can cause termination of signalling, and provides examples that illustrate the importance of these processes. Inactivation of voltage-gated Na(+) channels and the photoactivated rhodopsin molecule is caused by rapid conformational rearrangements. Negative feedback can also contribute to the termination of signalling for various mechanisms, including plasma membrane ion channels or cAMP signal generation. In immune cells, the tyrosine-based inhibitory motif (ITIM)-containing molecules are essential negative regulatory components. Desensitization of G-protein-coupled receptors can occur with homologous and heterologous mechanisms, mediated by β-arrestin molecules and second messenger-induced kinases respectively. In NF-κB signalling, resynthetized IκB and other enzymes form negative feedback loops. GTPase-activating proteins are also dedicated to termination of signalling, because they can switch off the small G proteins by increasing their endogenous GTP hydrolysis. In many systems, signal termination is a result of a combined action of several different mechanisms, which underlines the importance of these processes.     

Ethnic differences in the occurrence of the M1(ala213) haplotype of alpha-1-antitrypsin in asthmatic and non-asthmatic black and white South Africans

An ethnic study of 175 individuals, comprising 65 black and 110 white South Africans, has shown a conclusive difference in the frequency of the M1(ala²¹³) haplotype of α¹-antitrypsin (P < 0.00001). The M1(ala²¹³) haplotype occurred more frequently in the black group. In the latter group, the frequency of the M1(ala²¹³) haplotype was the same in both controls (0.55) and asthmatics (0.53). However, there was a significant difference in the frequencies (0.19 and 0.36) for the respective white groups (P < 0.01), the frequency of the M1(ala²¹³) haplotype being much higher in the asthmatics. Apart from the above differences, there was also a difference in the elastase-inhibitory capacities of the homozygote phenotypes M1(val²¹³) vs M1(ala²¹³) (P < 0.0001), this capacity being lower in the latter phenotype. We conclude that the occurrence of the M1(ala²¹³) allele of α¹-antitrypsin differs in various ethnic groups and may play a role in asthma.     

鼠抗人Syndecan-1分子功能性单克隆抗体的制备及其生物学特性

制备鼠抗人Syndecan-1(CD138)分子的功能性单克隆抗体,研究其对高表达CD138分子细胞的生物学效应。以人多发性骨髓瘤(MM)细胞株8226作为免疫原,8226和B淋巴瘤细胞株Daudi作为检测细胞株,利用B淋巴细胞杂交瘤技术制备单克隆抗体。以快速定性试纸分析法鉴定单抗所属的IgG亚类,采用间接免疫荧光标记法及竞争抑制实验分析单抗的亲和力和特异性,以高表达Syndecan-1的人多发性骨髓瘤细胞株XG-1为靶细胞,分析单抗对其生长的影响。结果:成功地获得1株鼠抗人Syndecan-1分子的功能性单克隆抗体杂交瘤细胞株(克隆4B3),经体外长期传代培养,液氮冻存半年以上反复复苏良好,分泌特异性抗体性能稳定。4B3分泌的单克隆抗体识别位点与单抗BB4识别位点相同或相近,重链为IgG1亚类,轻链为κ型,纯化后腹水中单克隆抗体蛋白的得率为2.9 mg/ml,加入4B3单克隆抗体后的XG-1细胞体外生长受到抑制,并可用于神经胶质瘤细胞的免疫组织化学检测。由此表明,4B3为功能性抗人Syndecan-1单克隆抗体,具有一定的基础研究和临床应用前景,这对进一步研究Syndecan-1分子的生物学特性也具有重要的价值。     

SLC40A1 Q248H allele frequencies and associated SLC40A1 haplotypes in three West African population samples

Background: Ferroportin is a transmembrane protein responsible for iron export from enterocytes and macrophages. Mutation c.744G → T (Q248H), located in exon 6 of the ferroportin gene SLC40A1, is found as a polymorphism in populations of African origin. This mutation has been extensively analysed in African-Americans, but poorly studied in native African populations.

Aim: To increase information about Q248H mutation frequency in native sub-Saharan populations examining three West African populations.

Subjects and methods: Samples from S. Tomé e Príncipe (n = 115), Angola (n = 156) and Republic of Guinea (n = 170) were analysed for Q248H mutation and for two polymorphisms, IVS1( ? 24)G → C and microsatellite (CGG)_n, using standard molecular methodology.

Results: The estimated frequencies of Q248H allele were 2.2% in S. Tomé e Príncipe, 3.5% in Angola and 4.1% in Republic of Guinea. Analysis of polymorphisms IVS1( ? 24)G → C and (CGG)_n showed mutation allele c.744T to be strongly associated with haplotype IVS1( ? 24)G/(CGG)₇.

Conclusions: This study confirmed the presence of Q248H mutation at polymorphic frequencies in three native sub-Saharan populations. Analysis of two additional markers in the same gene support a single origin of the mutant allele c.744T in the haplotype background IVS1( ? 24)G/(CGG)₇.     

Morphologic Analysis of M2 Macrophage in Glioblastoma: Involvement of Macrophage Extracellular Traps (METs)

Macrophages are classified into two phenotypes, M1 and M2, based on their roles. M2 macrophages suppress inflammation and increase in proportion to the malignancy of brain tumors. Recently, macrophage extracellular traps (METs), which change into a network, have been reported as a unique form of macrophage cell death. In this study, immunohistochemical analysis of macrophages in METs in human glioblastoma was performed. To distinguish between M1 and M2 macrophages, multiple immunostainings with Iba1 combined with CD163 or CD204 were performed. M2 macrophages were present in small amounts in normal and borderline areas but showed an increasing trend as they shifted to tumor areas, and most of them were the activated- or phagocytic-type. We also successfully detected METs coexisting with fibrin and lactoferrin near the border between the tumor and necrotic area. M2 macrophages not only suppressed inflammation but also were involved in the formation of METs. This study found that M2 macrophages play various roles in unstable situations.     

Determination of trace aflatoxin M1 levels in milk and milk products consumed in Turkey by using enzyme-linked immunosorbent assay

Aflatoxin M1 (AFM1) levels in milk and milk products (kasar cheese, tulum cheese, dil cheese, cream cheese, white cheese) consumed in Turkey were determined in this study by using enzyme-linked immunosorbent assay (ELISA). Extraction procedure was optimised to obtain high extraction efficiency. Recovery experiment was also performed to test the suitability of the extraction system and it was observed that % recovery values for AFM1 were higher than 92%. The method used in this study was simple and suitable for the detection of AFM1 in these matrices. Results found from the samples were compared with the requirements of Turkish Food Codex (TFC). As much as 42.16% of cheese samples analysed were contaminated while 61/77 milk samples were found to be contaminated with AFM1 in the range of 0.005–0.410 µg/L. It was found that five white cheese, one kasar cheese and four milk samples exceeded the criteria of 0.5 μg/kg for cheese and 0.05 μg/L for milk set by TFC.