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51.
Tamas Papp Angela Polyak Krisztina Papp Zoltan Meszar Roza Zakany Eva Meszar-Katona Palne Terdik Tünde Chang Hwa Ham Szabolcs Felszeghy 《International journal of oral science》2016,8(1):24-31
Although several heat shock proteins have been investigated in relation to tooth development, no available information is available about the spatial and temporal expression pattern of heat shock protein 60 (Hsp 60). To characterize Hsp 60 expression in the structures of the developing tooth germ, we used Western blotting, immunohistochemistry and in situ hybridization. Hsp 60 was present in high amounts in the inner and outer enamel epithelia, enamel knot (EK) and stratum intermedium (SI). Hsp 60 also appeared in odontoblasts beginning in the bell stage. To obtain data on the possible effect of Hsp 60 on isolated lower incisors from mice, we performed in vitro culturing. To investigate the effect of exogenous Hsp 60 on the cell cycle during culturing, we used the 5-bromo-2- deoxyuridine (BrdU) incorporation test on dental cells. Exogenously administered Hsp 60 caused bluntness at the apical part of the 16.5-day-old tooth germs, but it did not influence the proliferation rate of dental cells. We identified the expression of Hsp 60 in the developing tooth germ, which was present in high concentrations in the inner and outer enamel epithelia, EK, SI and odontoblasts. High concentration of exogenous Hsp 60 can cause abnormal morphology of the tooth germ, but it did not influence the proliferation rate of the dental cells. Our results suggest that increased levels of Hsp 60 may cause abnormalities in the morphological development of the tooth germ and support the data on the significance of Hsp during the developmental processes. 相似文献
52.
Mannion Anne F. Mariaux Francine Reitmeir Raluca Fekete Tamas F. Haschtmann Daniel Loibl Markus Jeszenszky Dezsö Kleinstück Frank S. Porchet François Elfering Achim 《European spine journal》2020,29(8):1935-1952
European Spine Journal - Depression, anxiety, catastrophising, and fear-avoidance beliefs are key "yellow flags" (YFs) that predict a poor outcome in back patients. Most surgeons... 相似文献
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Z.s. Varga M.P. Jacob L. Robert J. Csongor T. Fulop Jr. 《Experimental gerontology》1997,32(6):260-662
Effector functions of the elastin receptor on human phagocytic cells from young and older individuals were studied. In cells of young healthy subjects the elastin peptides, the agonists of receptor, stimulated both superoxide anion release from PMNs and phagocytosis of coated human red cells by monocytes. Elastin appeared to inhibit the cholesterol synthesis in monocytes, measured by the incorporation of 14C-acetate. In comparison with phagocytic cells of young (≤25 ± 6 years) subjects, PMNs of elderly donors (≥75 ±10 years) bore a similar number of binding sites for soluble elastin peptides, and the affinity of the elastin receptor was unchanged as shown by Scatchard analysis. The phagocytosis of coated human red cells stimulated by elastin peptides was also similar in the two age groups. However, several differences were found between phagocytic cells of young and elderly donors 1) PMNs of elderly released increased amounts of elastase from both resting and elastin peptide stimulated cells, and 2) monocytes of elderly showed a lack of inhibition of cholesterol synthesis by elastin peptides when maintained in cholesterol-free medium. These changes in effector functions of phagocytic cells from elderly donors might contribute to the age-dependent increase of susceptibility to the development of atherosclerotic lesions. 相似文献
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Eszter Banki Krisztina Kovacs Daniel Nagy Tamas Juhasz Peter Degrell Katalin Csanaky Peter Kiss Gabor Jancso Gabor Toth Andrea Tamas Dora Reglodi 《Journal of molecular neuroscience : MN》2014,54(3):300-309
Diabetic nephropathy is the leading cause of end-stage renal failure and accounts for 30–40 % of patients entering renal transplant programmes. The nephroprotective effects of the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP38) against diabetes have been shown previously, but the molecular mechanisms responsible for these effects remain unknown. In the present study, we showed that PACAP treatment counteracted the diabetes-induced increase in the level of the proapoptotic pp38MAPK and cleaved caspase-3 and also decreased the p60 subunit of NFκB. The examined antiapoptotic factors, including pAkt and pERK1/2, showed a slight increase in the diabetic kidneys, while PACAP treatment resulted in a notable elevation of these proteins. PCR and Western blot revealed the downregulation of fibrotic markers, like collagen IV and TGF-β1 in the kidney. PACAP treatment resulted in increased expression of the antioxidant glutathione. We conclude that the nephroprotective effect of PACAP in diabetes is, at least partly, due to its antiapoptotic, antifibrotic and antioxidative effect in addition to the previously described antiinflammatory effect. 相似文献
58.
G. Horvath D. Reglodi R. Brubel M. Halasz A. Barakonyi A. Tamas E. Fabian B. Opper G. Toth M. Cohen L. Szereday 《Journal of molecular neuroscience : MN》2014,54(3):320-330
Pituitary adenylate cyclase activating polypeptide (PACAP) is an endogenous neuropeptide having a widespread distribution both in the nervous system and peripheral organs including the female reproductive system. Both the peptide and its receptors have been shown in the placenta but its role in placental growth, especially its human aspects, remains unknown. The aim of the present study was to investigate the effects of PACAP on invasion, proliferation, cell survival, and angiogenesis of trophoblast cells. Furthermore, cytokine production was investigated in human decidual and peripheral blood mononuclear cells. For in vitro studies, human invasive proliferative extravillous cytotrophoblast (HIPEC) cells and HTR-8/SVneo human trophoblast cells were used. Both cell types were used for testing the effects of PACAP on invasion and cell survival in order to investigate whether the effects of PACAP in trophoblasts depend on the examined cell type. Invasion was studied by standardized invasion assay. PACAP increased proliferation in HIPEC cells, but not in HTR-8 cells. Cell viability was examined using MTT test, WST-1 assay, and annexin V/propidium iodide flow cytometry assay. Survival of HTR-8/SVneo cells was studied under oxidative stress conditions induced by hydrogen peroxide. PACAP as pretreatment, but not as co-treatment, significantly increased the number of surviving HTR-8 cells. Viability of HIPEC cells was investigated using methotrexate (MTX) toxicity, but PACAP1-38 could not counteract its toxic effect. Angiogenic molecules were determined both in the supernatant and the cell lysate by angiogenesis array. In the supernatant, we found that PACAP decreased the secretion of various angiogenic markers, such as angiopoietin, angiogenin, activin, endoglin, ADAMTS-1, and VEGF. For the cytokine assay, human decidual and peripheral blood lymphocytes were separated and treated with PACAP1-38. Th1 and Th2 cytokines were analyzed with CBA assay and the results showed that there were no significant differences in control and PACAP-treated cells. In summary, PACAP seems to play various roles in human trophoblast cells, depending on the cell type and microenvironmental influences. 相似文献
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Scott Nugent Sebastien Tremblay Kewei W. Chen Napatkamon Ayutyanont Auttawut Roontiva Christian-Alexandre Castellano Melanie Fortier Maggie Roy Alexandre Courchesne-Loyer Christian Bocti Martin Lepage Eric Turcotte Tamas Fulop Eric M. Reiman Stephen C. Cunnane 《Neurobiology of aging》2014
The extent to which the age-related decline in regional brain glucose uptake also applies to other important brain fuels is presently unknown. Ketones are the brain's major alternative fuel to glucose, so we developed a dual tracer positron emission tomography protocol to quantify and compare regional cerebral metabolic rates for glucose and the ketone, acetoacetate. Twenty healthy young adults (mean age, 26 years) and 24 healthy older adults (mean age, 74 years) were studied. In comparison with younger adults, older adults had 8 ± 6% (mean ± SD) lower cerebral metabolic rates for glucose in gray matter as a whole (p = 0.035), specifically in several frontal, temporal, and subcortical regions, as well as in the cingulate and insula (p ≤ 0.01, false discovery rate correction). The effect of age on cerebral metabolic rates for acetoacetate in gray matter did not reach significance (p = 0.11). Rate constants (min−1) of glucose (Kg) and acetoacetate (Ka) were significantly lower (−11 ± 6%; [p = 0.005], and −19 ± 5%; [p = 0.006], respectively) in older adults compared with younger adults. There were differential effects of age on Kg and Ka as seen by significant interaction effects in the caudate (p = 0.030) and post-central gyrus (p = 0.023). The acetoacetate index, which expresses the scaled residuals of the voxel-wise linear regression of glucose on ketone uptake, identifies regions taking up higher or lower amounts of acetoacetate relative to glucose. The acetoacetate index was higher in the caudate of young adults when compared with older adults (p ≤ 0.05 false discovery rate correction). This study provides new information about glucose and ketone metabolism in the human brain and a comparison of the extent to which their regional use changes during normal aging. 相似文献