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71.
Deborah Schmitz Jan W. Robering Volker Weisbach Andreas Arkudas Ingo Ludolph Raymund E. Horch Anja M. Boos Annika KengelbachWeigand 《Journal of cellular and molecular medicine》2022,26(16):4463
Adipose‐derived stromal cells (ADSC) are increasingly used in clinical applications due to their regenerative capabilities. However, ADSC therapies show variable results. This study analysed the effects of specific factors of ex‐obese patients on ADSC functions. ADSC were harvested from abdominal tissues (N = 20) after massive weight loss. Patients were grouped according to age, sex, current and maximum body mass index (BMI), BMI difference, weight loss method, smoking and infection at the surgical site. ADSC surface markers, viability, migration, transmigration, sprouting, differentiation potential, cytokine secretion, telomere length and mtDNA copy number were analysed. All ADSC expressed CD73, CD90, CD105, while functional properties differed significantly among patients. A high BMI difference due to massive weight loss was negatively correlated with ADSC proliferation, migration and transmigration, while age, sex or weight loss method had a smaller effect. ADSC from female and younger donors and individuals after weight loss by increase of exercise and diet change had a higher activity. Telomere length, mtDNA copy number, differentiation potential and the secretome did not correlate with patient factors or cell function. Therefore, we suggest that factors such as age, sex, increase of exercise and especially weight loss should be considered for patient selection and planning of regenerative therapies. 相似文献
72.
TGF-beta and the regulation of neuron survival and death. 总被引:5,自引:0,他引:5
Kerstin Krieglstein Jens Strelau Andreas Schober Aideen Sullivan Klaus Unsicker 《Journal of Physiology》2002,96(1-2):25-30
Transforming growth factor-betas (TGF-betas) constitute a superfamily of multifunctional cytokines with important implications in morphogenesis, cell differentiation, and tissue remodeling. In the developing nervous system, TGF-beta2 and -beta3 occur in radial and astroglial cells as well as in many populations of postmitotic, differentiating neurons. TGF-beta1 is restricted to the choroid plexus and meninges. In addition to functions related to glial cell maturation and performances, TGF-beta2 and -beta3 are important regulators of neuron survival. In contrast to neurotrophic factors, as for example, neurotrophins, TGF-betas are most likely not neurotrophic by themselves. However, they can dramatically increase the potency of select neurotrophins, fibroblast growth factor-2, ciliary neurotrophic factor, and glial cell line-derived neurotrophic factor (GDNF). In the case of GDNF, we have shown that GDNF fails to promote the survival of highly purified neuron populations in vitro unless it is supplemented with TGF-beta. This also applies to the in vivo situation, where antibodies to all three TGF-beta isoforms fully prevent the trophic effect of GDNF on axotomized, target-deprived neurons. In addition to the TGF-beta isoforms -beta2 and -beta3, other members of the TGF-beta superfamily are expressed in the nervous system having important roles in embryonic patterning, cell migration, and neuronal transmitter determination. We have cloned and expressed a novel TGF-beta, named growth/differentiation factor-15 (GDF-15). GDF-15 is synthesized in the choroid plexus and released into the CSF, but also occurs in all regions investigated of the developing and adult brain. GDF-15 is a potent trophic factor for developing and 6-OHDA-lesioned midbrain dopaminergic neurons in vitro and in vivo, matching the potency of GDNF. 相似文献
73.
Clubroot, caused by Plasmodiophora brassicae, is a severe soil-borne disease that restricts the production of cruciferous crops worldwide. A better understanding of biotic and abiotic factors regulating germination of P. brassicae resting spores in the soil is significant for developing novel control methods. Previous studies reported that root exudates can trigger P. brassicae resting spore germination, thus enabling a targeted attack of P. brassicae on host plant roots. However, we found that native root exudates collected under sterile conditions from host or non-host plants cannot stimulate the germination of sterile spores, indicating that root exudates may not be direct stimulation factors. Instead, our studies demonstrate that soil bacteria are essential for triggering germination. Through 16s rRNA amplicon sequencing analysis, we found that certain carbon sources and nitrate can reshape the initial microbial community to an inducing community leading to the germination of P. brassicae resting spores. The stimulating communities significantly differed in composition and abundance of bacterial taxa compared to the non-stimulating ones. Several enriched bacterial taxa in stimulating community were significantly correlated with spore germination rates and may be involved as stimulation factors. Based on our findings, a multi-factorial ‘pathobiome’ model comprising abiotic and biotic factors is proposed to represent the putative plant-microbiome-pathogen interactions associated with breaking spore dormancy of P. brassicae in soil. This study presents novel views on P. brassicae pathogenicity and lays the foundation for novel sustainable control strategies of clubroot. 相似文献
74.
Huber M Bahr I Krätzschmar JR Becker A Müller EC Donner P Pohlenz HD Schneider MR Sommer A 《Molecular & cellular proteomics : MCP》2004,3(1):43-55
In search of novel mechanisms leading to the development of antiestrogen-resistance in human breast tumors, we analyzed differences in the gene and protein expression pattern of the human breast carcinoma cell line T47D and its derivative T47D-r, which is resistant toward the pure antiestrogen ZM 182780 (Faslodex trade mark, fulvestrant). Affymetrix DNA chip hybridizations on the commercially available HuGeneFL and Hu95A arrays were carried out in parallel to the proteomics analysis where the total cellular protein content of T47D or T47D-r was separated on two-dimensional gels. Thirty-eight proteins were found to be reproducibly up- or down-regulated more than 2-fold in T47D-r versus T47D in the proteomics analysis. Comparison with differential mRNA analysis revealed that 19 of these were up- or down-regulated in parallel with the corresponding mRNA molecules, among which are the protease cathepsin D, the GTPases Rab11a and MxA, and the secreted protein hAG-2. For 11 proteins, the corresponding mRNA was not found to be differentially expressed, and for eight proteins an inverse regulation was found at the mRNA level. In summary, mRNA expression data, when combined with proteomic information, provide a more detailed picture of how breast cancer cells are altered in their antiestrogen-resistant compared with the antiestrogen-sensitive state. 相似文献
75.
Peinelt C Vig M Koomoa DL Beck A Nadler MJ Koblan-Huberson M Lis A Fleig A Penner R Kinet JP 《Nature cell biology》2006,8(7):771-773
Depletion of intracellular calcium stores activates store-operated calcium entry across the plasma membrane in many cells. STIM1, the putative calcium sensor in the endoplasmic reticulum, and the calcium release-activated calcium (CRAC) modulator CRACM1 (also known as Orai1) in the plasma membrane have recently been shown to be essential for controlling the store-operated CRAC current (I(CRAC)). However, individual overexpression of either protein fails to significantly amplify I(CRAC). Here, we show that STIM1 and CRACM1 interact functionally. Overexpression of both proteins greatly potentiates I(CRAC), suggesting that STIM1 and CRACM1 mutually limit store-operated currents and that CRACM1 may be the long-sought CRAC channel. 相似文献
76.
Anja Mittag Dominik Lenz Andreas O H Gerstner Ulrich Sack Michael Steinbrecher Mario Koksch Alexander Raffael Jozsef Bocsi Attila Tárnok 《Cytometry. Part A》2005,65(2):103-115
BACKGROUND: Natural killer (NK) and NK T (NKT) cells are important in innate immune defense. Their unequivocal identification requires at least four antigens. Based on the expression of additional antigens, they can be further divided into functional subsets. For more accurate immunophenotyping and to describe multiple expression patterns of leukocyte subsets, an increased number of measurable colors is necessary. To take advantage of the technologic features offered by slide-based cytometry, repeated analysis was combined with sequential optical-filter changing. METHODS: Human peripheral blood leukocytes from healthy adult volunteers were labeled with antibodies by direct or indirect staining. Tandem dyes of Cy7 (phycoerythrin [PE]-/allophycocyanin [APC]-Cy7), Cy5.5 (PE-/APC-Cy5.5), and PE-Cy5 and the fluorochromes fluorescein isothiocyanate (FITC), PE, and APC were tested alone and in combinations. Optical filters of the laser scanning cytometer were 555 DRLP/BP 530/30 nm for photomultiplier tube (PMT) 1/FITC, 605 DRLP/BP 580/30 nm for PMT 2/PE, 740 DCXR/BP 670/20 nm for PMT 3/Cy5/APC, and BP 810/90 nm for PMT 4/Cy7. Filter PMT 3 was replaced for detection of PE/Cy5.5 and APC/Cy5.5 by 740 LP/BP 710/20 nm and the sample was remeasured. Both data files were merged into one to combine the different information on a single-cell basis. The combination of eight antibodies against CD3, CD4, CD8, CD14, CD16, CD19, CD45, and CD56 was used to characterize NK and NKT cells and their subsets. RESULTS: In this way Cy5.5 is measurable at 488-nm and 633-nm excitation. Further, with the two different filters it is possible to distinguish Cy5 from Cy5.5 in the same detection channel (PMT 3). With this method we identified NK and NKT cells, subsets of NK (CD3-16+56+, CD3-16+56-, CD3-16-56+) and NKT (CD3+16+56+, CD3+16-56+) and their CD4+8-, CD4-8+, CD4-8- and CD4+8+ subsets. CONCLUSION: With our adaptations it is possible to discriminate tandem conjugates of Cy5, Cy5.5, and Cy7 for eight-color immunophenotyping. Using this method, novel rare subsets of NK and NKT cells that are CD4/CD8 double positive are reported for the first time. 相似文献
77.
A number of hypotheses have been presented regarding the originsof the metazoans and, more specifically, the Bilateria. Usingvarious phylogenetic analyses, characteristics have been mappedon phylogenetic trees to infer ancestral body plans and lifehistory strategies of those ancestors. Many arguments on theevolution of the Bilateria are based on the presumed homologyof certain characteristics of extant larva and adults, includingvarious ciliated bands involved in feeding and locomotion. Thisarticle considers a recent study indicating that the second,downstream-collecting, ciliated band in the veliger larva ofthe gastropod mollusc, Crepidula fornicata, is actually derivedfrom secondary trochoblasts (derived from second quartet micromeres),that normally form part of the prototrochal band found in otherspiralian phyla (Hejnol et al. 2007). Despite previous arguments,these new findings suggest that the second ciliated band inthe veliger larva is not homologous to the metatroch found inthe trochophore larva of some other spiralians, such as theannelid, Polygordius lacteus. In the latter case, the metatrochwas reported to be formed by a different set of lineage precursors(derived from third quartet micromeres) (Woltereck 1904). Thesefindings have important implications for the interpretationof various hypotheses related to the evolution of metazoan phyla. 相似文献
78.
79.
Little detailed information exists on the anatomy of the nervous system and the musculature of Entoprocta. Herein we describe the distribution of the neurotransmitters RFamide and serotonin as well as the myo-anatomy of adults and asexually produced budding stages of the solitary entoproct species Loxosomella vivipara and L. parguerensis using immunocytochemistry and epifluorescence as well as confocal microscopy. The development of the RFamidergic and serotonergic nervous system starts in early budding stages. In the adults, RFamide is present in the bilateral symmetric cerebral ganglion, a pair of oral nerves that innervate two pairs of nerve cell clusters in the heel of the foot, a pair of aboral nerves, the paired lateral nerves, the calyx nerves, the atrial ring nerve, the tentacle nerves, the stomach nerves, and the rectal nerves. Serotonin is only found in the cerebral ganglion, the oral nerves, and in the tentacle nerves. Some differences in the distribution of both neurotransmitters were found between L. vivipara and L. parguerensis and are most obvious in the differing number of large serotonergic perikarya associated with the oral nerves. Nerves arising from the cerebral ganglion and running in a ventral direction have not been described for Entoprocta before, and the homology of these to the ventral nerve cords of other Spiralia is considered possible. The body musculature of both Loxosomella species comprises longitudinal and diagonal muscles in the foot, the stalk, and the calyx. We found several circular muscles in the calyx. The stalk and parts of the foot and the calyx are surrounded by a fine outer layer of ring muscles. In addition to the congruent details regarding the myo-anatomy of both species, species-specific muscle structures could be revealed. The comparison of our data with recent findings of the myo-anatomy of two Loxosoma species indicates that longitudinal and diagonal body muscles, atrial ring muscles, tentacle muscles, esophageal and rectal ring muscles, as well as intestinal and anal sphincters are probably part of the ancestral entoproct muscle bauplan. 相似文献
80.
Brunner S Herndler-Brandstetter D Arnold CR Wiegers GJ Villunger A Hackl M Grillari J Moreno-Villanueva M Bürkle A Grubeck-Loebenstein B 《Aging cell》2012,11(4):579-587
The life-long homeostasis of memory CD8(+) T cells as well as persistent viral infections have been shown to facilitate the accumulation of highly differentiated CD8(+) CD28(-) T cells, a phenomenon that has been associated with an impaired immune function in humans. However, the molecular mechanisms regulating homeostasis of CD8(+) CD28(-) T cells have not yet been elucidated. In this study, we demonstrate that the miR-23~24~27 cluster is up-regulated during post-thymic CD8(+) T-cell differentiation in humans. The increased expression of miR-24 in CD8(+) CD28(-) T cells is associated with decreased expression of the histone variant H2AX, a protein that plays a key role in the DNA damage response (DDR). Following treatment with the classic chemotherapeutic agent etoposide, a topoisomerase II inhibitor, apoptosis was increased in CD8(+) CD28(-) when compared to CD8(+) CD28(+) T cells and correlated with an impaired DDR in this cell type. The reduced capacity of CD8(+) CD28(-) T cell to repair DNA was characterized by the automated fluorimetric analysis of DNA unwinding (FADU) assay as well as by decreased phosphorylation of H2AX at Ser139, of ATM at Ser1981, and of p53 at Ser15. Interleukin (IL)-15 could prevent etoposide-mediated apoptosis of CD8(+) CD28(-) T cells, suggesting a role for IL-15 in the survival and the age-dependent accumulation of CD8(+) CD28(-) T cells in humans. 相似文献