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51.
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Elin Nilsson Constantin Bodolea Torsten Gordh Anders Larsson 《Neurological sciences》2013,34(4):445-448
Cathepsins are increased in the brain of elderly animals. We investigate the presence of cathepsin B and S in human cerebrospinal fluid (CSF) plasma and the associations with cystatin C, age and sex. We measured cathepsin B and S concentrations in CSFs from 118 persons, undergoing elective surgical procedures, with ELISA. Both cathepsin B and cathepsin S were positively correlated with age. No correlation was observed between cathepsin B or S and length, height or body mass index. Both cathepsin B and S were positively correlated to the cystatin C concentration in CSF. Calculated reference intervals were 4,893–17,636 pg/mL for cathepsin B and 2,681–11,459 pg/mL for cathepsin S. Elderly individuals had significantly higher levels of both cathepsin B (r s = 0.38, p = 0.00002) and cathepsin S (r s = 0.35, p = 0.0001) in CSF. 相似文献
53.
Mugurel Constantin Rusu Andreea Cristiana Didilescu Ruxandra Stănescu Florinel Pop Valentina Mariana Mănoiu Adelina Maria Jianu Marek Vâlcu 《Anatomical record (Hoboken, N.J. : 2007)》2013,296(2):350-363
This study aimed to evaluate by immunohistochemistry and transmission electron microscopy (TEM) the morphological features of the oral mucosa endothelial tip cells (ETCs) and to determine the immune and ultrastructural patterns of the stromal nonimmune cells which could influence healing processes. Immune labeling was performed on bioptic samples obtained from six edentulous patients undergoing surgery for dental implants placement; three normal samples were collected from patients prior to the extraction of the third mandibular molar. The antibodies were tested for CD34, CD117(c‐kit), platelet derived growth factor receptor‐alpha (PDGFR‐α), Mast Cell Tryptase, CD44, vimentin, CD45, CD105, alpha‐smooth muscle actin, FGF2, Ki67. In light microscopy, while stromal cells (StrCs) of the reparatory and normal oral mucosa, with a fibroblastic appearance, were found positive for a CD34/CD44/CD45/CD105/PDGFR‐α/vimentin immune phenotype, the CD117/c‐kit labeling led to a positive stromal reaction only in the reparatory mucosa. In TEM, non‐immune StrCs presenting particular ultrastructural features were identified as circulating fibrocytes (CFCs). Within the lamina propria CFCs were in close contact with ETCs. Long processes of the ETCs were moniliform, and hook‐like collaterals were arising from the dilated segments, suggestive for a different stage migration. Maintenance and healing of oral mucosa are so supported by extensive processes of angiogenesis, guided by ETCs that, in turn, are influenced by the CFCs that populate the stromal compartment both in normal and reparatory states. Therefore, CFCs could be targeted by specific therapies, with pro‐ or anti‐angiogenic purposes. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
54.
Constantin Lürenbaum Britta Vortmann-Westhoven Marco Evertz Martin Winter Sascha Nowak 《RSC advances》2020,10(12):7083
Diminishing the loss of performance of lithium ion batteries (LIBs) is a challenge that is yet to be fulfilled. Understanding of deterioration processes and mechanisms (i.e., so-called aging) requires analytically accurate examination of aged cells. Changes in the distribution of lithium or transition metals in the LIB cells can influence their cycle and calendar life significantly. As electrochemically treated cells and especially their electrodes do not age homogeneously and the local electrochemistry (e.g. deposition patterns) is strongly dependent on surface properties, bulk analysis is not a satisfactory investigation method. Therefore, a surface sensitive method, namely laser ablation-inductively coupled plasma-optical emission spectrometry (LA-ICP-OES) is presented. LIB cells with lithium metal oxide LiNi1/3Co1/3Mn1/3O2 (NCM111) as cathode material and graphite as anode material are investigated using a 213 nm Nd:YAG laser.An LA-ICP-OES method was developed and applied to investigate the transition metal dissolution in lithium batteries as well as lithium deposition e.g. in case of short circuits. 相似文献
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Emmanuel P. Gilissen Karelle Leroy Zehra Yilmaz Enikö Kövari Constantin Bouras Alain Boom Luc Poncelet Joseph M. Erwin Chet C. Sherwood Patrick R. Hof Jean-Pierre Brion 《Brain structure & function》2016,221(1):647-664
Lipofuscin pigment accumulation is among the most prominent markers of cellular aging in postmitotic cells. The formation of lipofuscin is related to oxidative enzymatic activity and free radical-induced lipid peroxidation. In various mammals such as rat, dog, macaque as well as in cheirogaleid primates, most of the large neurons, such as cerebellar Purkinje cells and neocortical pyramidal cells, show heavy lipofuscin accumulation in adulthood. In contrast, a well-known yet poorly studied feature of the aging human brain is that although lipofuscin accumulation is most marked in large neurons of the cerebral cortex, the large neurons of the cerebellar cortex—the Purkinje cells—appear to remain free of lipofuscin accumulation. It is however, not known whether this characteristic of human Purkinje cells is shared with other primates or other mammals. This study reports results from histological observation of Purkinje cells in humans, non-human primates, and other mammals. Procedures include histochemistry, immunocytochemistry, and fluorescence microscopy. Abundant lipofuscin deposition was observed in Purkinje cells of all the species we examined except Homo sapiens (including Alzheimer’s disease cases) and Pan troglodytes. In contrast, lipofuscin deposition was observed in neurons of the dentate nucleus. Our findings suggest that when compared with other primates, Purkinje cells in chimpanzees and humans might share a common aging pattern that involves mechanisms for neuroprotection. This observation is important when considering animal models of aging. 相似文献
59.
T and B lymphocyte depletion has a marked effect on the fibrosis of dystrophic skeletal muscles in the scid/mdx mouse 总被引:1,自引:0,他引:1
Farini A Meregalli M Belicchi M Battistelli M Parolini D D'Antona G Gavina M Ottoboni L Constantin G Bottinelli R Torrente Y 《The Journal of pathology》2007,213(2):229-238
Abnormal connective tissue proliferation following muscle degeneration is a major pathological feature of Duchenne muscular dystrophy (DMD), a genetic myopathy due to lack of the sarcolemmal dystrophin protein. Since this fibrotic proliferation is likely to be a major obstacle to the efficacy of future therapies, research is needed to understand and prevent the fibrotic process in order to develop an effective treatment. Murine muscular dystrophy (mdx) is genetically homologous to DMD, and histopatological alterations are comparable to those of the muscles of patients with DMD. To investigate the development of fibrosis, we bred the mdx mouse with the scid immunodepressed mouse and analysed fibrosis histologically; we used ELISA analysis to determine TGF-beta1 expression. Significant reduction of fibrosis and TGF-beta1 expression was found in the muscles of the scid/mdx mice. However, we observed similar centrally located nuclei, necrosis, muscle degeneration and muscle force compared to the mdx animals. These data demonstrate a correlation between the absence of B and T lymphocytes and loss of fibrosis accompanied by reduction of TGF-beta1, suggesting the importance of modulation of the immune system in DMD. 相似文献
60.
Treatment of rheumatoid arthritis was deeply modified with the availability since 1999 of anti-TNFalpha. The clinical superiority of these drugs compared to traditional treatments is proven, but can one make the assumption that the cost of these innovative treatments is partially compensated by a reduction of consumption of other health resources? A retrospective observational study was carried out in the Midi-Pyrenees area, from the point of view of health insurance, to compare the consumed health resources between two cohorts of patients, one treated by etanercept (Enbrel) and the other by leflunomide (Arava). Two hundred and fifty three patients were included in the etanercept cohort and 539 in the leflunomide cohort. The average annual PR cost for a patient treated with etanercept is 13 936 euro and 5 764 euro for a patient treated with leflunomide. The health costs avoided by recourse to etanercept do not compensate the high cost of this drug. 相似文献