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1.
Julie Despres Yasmina Ramdani Marine di Giovanni Magalie Bnard Abderrakib Zahid Mait Montero‐Hadjadje Florent Yvergnaux Thibaut Saguet Azeddine Driouich Marie‐Laure Follet‐Gueye 《Experimental dermatology》2019,28(8):922-932
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing. 相似文献
2.
《Vaccine》2022,40(11):1594-1605
In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes. 相似文献
3.
4.
张献彩 《山西医科大学学报》2015,(1)
目的:观察糖尿病小鼠小肠绒毛杯状细胞分泌的黏原颗粒是否改变,为进一步研究糖尿病的消化系统并发症提供形态学基础。方法分别选取3,5,8,10月龄db/db糖尿病小鼠及相应年龄段的db/+m正常小鼠,每组6只,标本用4%多聚甲醛灌流固定后,从距Treitz韧带约10 cm处切下一段空肠,用PAS染色方法对小肠杯状细胞分泌的黏原颗粒进行观察。结果糖尿病组小肠绒毛易被破坏,糖尿病组中杯状细胞的分泌物比同月份正常对照组显著增加(P<0.05);糖尿病组中3月龄的杯状细胞分泌物最多,8月龄最少,并且8月龄分别与3月龄、5月龄比较均存在着显著差异(P<0.05);正常对照组随月龄增长无显著性差异(P>0.05)。结论糖尿病时杯状细胞分泌物增多可能对小肠绒毛有保护作用。 相似文献
5.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD. 相似文献
6.
P16INK4、PCNA在肺癌中表达的研究 总被引:3,自引:0,他引:3
目的 通过检测肺癌组织中p16、PCNA的表达,探讨其在肺癌发生发展中的作用及相互关系。方法 采用S—P免疫组化方法,检测83例肺癌标本及15例正常肺组织标本中P16^INK4和PCNA的表达。结果 P16^INK4和PCNA在正常肺组织和肺癌组织中表达的阳性率存在显著性差异。P16^INK4表达的阳性率在小细胞癌与非小细胞癌之间有显著性差异。PNTM分期高的肺癌标本P16^INK4及PCNA表达阳性率显著高于分期低的肺癌标本。不同分化程度的肺癌组织P16^INK4及PCNA表达阳性率有显著性差异。结论 肺癌的发生与P16^INK4的低表达和PCNA的高表达有关。而P16^INK4的表达与肺癌的组织学类型、分化程度、临床分期有关;PCNA的表达与肺癌的分化程度、临床分期有关。 相似文献
7.
L Peichl 《The Journal of comparative neurology》1992,324(4):590-602
The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat. 相似文献
8.
M Marín-Padilla 《The Journal of comparative neurology》1992,321(2):223-240
The prenatal development of the mammalian neocortex has been analyzed, with the rapid Golgi method, in a variety of experimental animals (hamster, mouse, rat, and cat) and in humans. A new developmental conception of the structural organization of the mammalian neocortex is discussed. Neocortical development begins with the establishment of the primordial plexiform layer (PPL) which precedes and is a prerequisite for the subsequent formation of the cortical plate (CP). The formation of the CP occurs, in its entirety, within the PPL. During its development, three fundamental neuronal events occur: migration, early differentiation, and late maturation. All migrating neurons, travelling on radial glial fibers, reach layer I, develop an apical dendrite, and establish contacts with its elements. These newly differentiated neurons assume similar morphology resembling embryonic pyramidal cells. As such, an early differentiation stage common to all neurons of the CP is established. During the late maturation stage, all CP neurons acquire their specific phenotypic structural and functional features. Only pyramidal neurons retain and expand their original connections with layer I while other neuronal types lose these connections. The pyramidal cell is redefined in developmental terms: the neocortex's pyramidal cell is both structurally and functionally locked into position between layer I and the cortical depth of its soma. During mammalian evolution pyramidal cells are forced to structurally and functionally elongate their apical dendrite outwardly to accommodate an increasing amount of information without losing either their original anchorage to layer I or their cortical depth. This unique property of pyramidal neurons is considered to be a mammalian innovation. Based on these observations, a unifying developmental cytoarchitectonic theory applicable to all mammals is proposed. The theory considers the CP to be a mammalian innovation and to represent a single, stratified, and expanding telencephalic nucleus. The theory envisions the mammalian neocortex as an open biological system capable of progressive expansion by the recruitment and transformation of primitive neurons from upper layer II into pyramidal cells. Hence, the number of pyramidal cell strata increases over the course of mammalian phylogeny. The developmental roles of layer I in the migration of neurons, formation of the CP, unique morphology of pyramidal cells, and overall structural organization of the mammalian neocortex are emphasized. 相似文献
9.
10.
目的 探讨河南汉族群体的D1S5 49、D3S175 4、D2 2S683和CSF1PO、TPOX、TH0 1基因座遗传多态性分布。方法 ACD抗凝血样采自 2 19名无血缘关系汉族个体 ,酚 氯仿法提取DNA ,应用复合扩增技术对D1S5 49等 6个短串重复序列 (STR)基因座进行扩增 ,采用高分辨率的聚丙烯酰胺凝胶电泳分离、银染法显影技术。统计各基因频率、计算杂合度、多态信息含量、个人识别概率及亲权否定概率。结果 6个STR基因座基因频率的分布均符合Hardy Weinberg平衡 ,各基因座的杂合度分别为 0 .7964、0 .72 3 1、0 .815 9、0 .75 81、0 .65 2 3、0 .6816;非父排除概率为 0 .62 46、0 .4914、0 .65 0 1、0 .5 2 3 6、0 .40 98、0 .42 87;个人识别机率为 0 .8996、0 .8781、0 .92 3 1、0 .8896、0 .8167、0 .83 92 ;多态信息含量为 0 .72 16、0 .6994、0 .742 1、0 .7169、0 .65 17、0 .710 6。结论 D1S5 49等 6个STR基因座是一组高度多态性的遗传标记系统 ,在人类遗传学及法医学研究中具有重要意义 相似文献