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61.
62.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
63.
No contribution of multipotent mesenchymal stromal cells to liver regeneration in a rat model of prolonged hepatic injury 总被引:6,自引:0,他引:6
Popp FC Slowik P Eggenhofer E Renner P Lang SA Stoeltzing O Geissler EK Piso P Schlitt HJ Dahlke MH 《Stem cells (Dayton, Ohio)》2007,25(3):639-645
Multipotent mesenchymal stromal (MS) cells from adult bone marrow are a cell population that can be expanded to large numbers in culture. MS cells might be differentiated toward hepatocytes in vitro and thus are promising candidates for therapeutic applications in vivo. The efficacy of bone marrow-derived MS cells versus hepatocytes to contribute to liver regeneration was compared in a rat model of prolonged toxic hepatic injury. Liver damage was induced by injection of carbon tetrachloride (CCl(4)) or allyl alcohol (AA) with and without retrorsine (R) pretreatment. MS cells or hepatocytes of wild-type F344 rats were injected into dipeptidyl peptidase IV (DPPIV)-deficient syngeneic rats. Hepatocyte chimerism was higher after intraportal hepatocyte transplantation in the R/AA group (mean maximal cluster size [MCS] = 21 cells) compared with the R/CCl(4) treatment group (MCS = 18). No hepatocyte engraftment was outlined following post-transplant CCl(4) injection only, whereas mere AA injection resulted in small clusters of donor-derived hepatocytes (MCS = 2). Intraparenchymal injection of hepatocytes was associated with a MCS = 11 after R/AA treatment and a MCS = 6 after AA administration alone. Redistribution of MS cells to the liver was shown after intraportal and intraparenchymal injection. In contrast to hepatocyte transplantation, however, donor-derived DPPIV-positive cells could not be demonstrated in any recipient after MS cell transplantation. Data from the present study indicate that a well-defined population of MS cells obtained according to established standard protocols does not differentiate into hepatocytes in vivo when transplanted under regenerative conditions, in which the application of hepatocytes results in stable hepatic engraftment. 相似文献
64.
Burkhard Maria Helmke Marcus Renner Annemarie Poustka Peter Schirmacher Jan Mollenhauer & Michael André Kern 《Histopathology》2009,54(2):233-240
Aims: Anorectal melanoma (AM) forms a rare but highly malignant subset of mucosal melanoma with an extremely poor prognosis. Although AMs display histological and immunohistochemical features very similar to cutaneous melanoma (CM), no association exists either with exposure to ultraviolet light or with melanocytic naevi. While AMs are clearly distinguished from CM by displaying few BRAF mutations, they are commonly indistinguishable from CM at the level of gene expression. The aim was to carry out expression analyses of classical immunohistochemical markers and of the protein deleted in malignant brain tumours 1 (DMBT1) in cases of primary anorectal malignant melanoma and CM.
Methods and results: Expression analyses of classical immunohistochemical markers (S100, HMB45, Melan A and MiTF) and of the protein DMBT1 were carried out in 27 cases of primary anorectal malignant melanoma and 26 cases of CM. All AM cases analysed showed expression of at least three of the classical markers for melanoma. However, immunohistochemistry showed 19 out of 27 AM to be positive for DMBT1, which represented a statistically significant difference ( P = 0.0009) compared with CM (six out of 26), which more commonly are negative for DMBT1 expression.
Conclusion: These results identify DMBT1 as a molecular feature that may allow distinction between AM and CM and support the notion that AM represents an entity molecularly distinct from CM. 相似文献
Methods and results: Expression analyses of classical immunohistochemical markers (S100, HMB45, Melan A and MiTF) and of the protein DMBT1 were carried out in 27 cases of primary anorectal malignant melanoma and 26 cases of CM. All AM cases analysed showed expression of at least three of the classical markers for melanoma. However, immunohistochemistry showed 19 out of 27 AM to be positive for DMBT1, which represented a statistically significant difference ( P = 0.0009) compared with CM (six out of 26), which more commonly are negative for DMBT1 expression.
Conclusion: These results identify DMBT1 as a molecular feature that may allow distinction between AM and CM and support the notion that AM represents an entity molecularly distinct from CM. 相似文献
65.
Corticotropin releasing factor influences aggression and monoamines: modulation of attacks and retreats 总被引:1,自引:0,他引:1
Carpenter RE Korzan WJ Bockholt C Watt MJ Forster GL Renner KJ Summers CH 《Neuroscience》2009,158(2):412-425
Salmonids establish social hierarchies as a result of aggressive social interactions. The establishment of dominant or subordinate status is strongly linked to neuroendocrine responses mediated through the stress axis. In this study, we tested the effects of introcerebroventricular (icv) corticotropin releasing factor (CRF) on the behavioral outcome, plasma cortisol and monoamine function in trout subjected to a socially aggressive encounter. Rainbow trout were treated with an icv injection of artificial cerebrospinal fluid (aCSF), 500 or 2000 ng ovine CRF, or not injected. Fish were allowed to interact with a similarly sized conspecific for 15 min. Following the behavioral interaction, plasma cortisol and central monoamine concentrations were analyzed. Trout treated with CRF were victorious in approximately 66% of the aggressive encounters against aCSF-treated opponents. Trout injected with CRF exhibited a reduction in the total number of attacks and decreased latency to attack. When trout were divided into winners and losers, only victorious CRF-treated fish exhibited a reduced latency to attack and fewer retreats. Social stress increased cortisol levels in both winners and losers of aggressive interaction. This effect was enhanced with the additional stress incurred from icv injection of aCSF. However, icv CRF in addition to social stress decreased plasma cortisol in both winners and losers. While aggression stimulated significant changes in serotonergic and dopaminergic activity, the magnitude and direction were dependent on limbic brain region, CRF dose, and outcome of social aggression. With broad effects on aggressive behavior, anxiety, stress responsiveness, and central monoaminergic activity, CRF plays an important role in modulating the behavioral components of social interaction. 相似文献
66.
Male Anolis carolinensis that win aggressive interactions mobilize neuroendocrine responses to social stress more rapidly than defeated lizards. We initially examined temporal patterns of neuroendocrine response to restraint stress in lizards of unknown status, and then investigated whether winning males respond more rapidly to this non-social stressor. Size-matched male pairs interacted to establish social status, and then were returned to individual home cages for 3 days. Plasma and brains were collected from non-restrained dominants and subordinates, and from a non-interacting control group. Additional groups of dominants and subordinates underwent 90 s restraint stress, with plasma and brains collected either immediately or 300 s after restraint. In lizards of unknown social status restraint stimulated rapid monoaminergic responses in nucleus accumbens, hippocampus, amygdala, and locus ceruleus, with delayed responses seen in VTA and raphé. Non-restrained dominants and subordinates had lower levels of raphé serotonergic activity and lower hippocampal dopaminergic activity 3 days after interacting, compared to controls. Dominants had higher corticosterone levels, both immediately and 300 s after restraint, than either non-restrained dominants or restrained subordinates. Restraint induced higher raphé serotonergic activity in dominants. However, subordinates also showed rapid responses to restraint; exhibiting lower hippocampal dopamine (DA) levels than non-restrained subordinates. At 300 s after the stress, amygdalar serotonin levels increased in dominants, while subordinates showed higher amygdalar DA levels. These results suggest that stressful aggressive interactions will not only alter basal neurochemical activity, but also influence neuroendocrine responses to non-social stressors according to individual social status. 相似文献
67.
E. Turkstra J. Gamble D. K. Creedy J. Fenwick L. Barclay A. Buist EL. Ryding P. A. Scuffham 《Archives of women's mental health》2013,16(6):561-564
We investigated the impact of pre-existing mental ill health on postpartum maternal outcomes. Women reporting childbirth trauma received counselling (Promoting Resilience in Mothers' Emotions; n?=?137) or parenting support (n?=?125) at birth and 6 weeks. The EuroQol Five dimensional (EQ-5D)-measured health-related quality of life at 6 weeks, 6 and 12 months. At 12 months, EQ-5D was better for women without mental health problems receiving PRIME (mean difference (MD) 0.06; 95 % confidence interval (CI) 0.02 to 0.10) or parenting support (MD 0.08; 95 % CI 0.01 to 0.14). Pre-existing mental health conditions influence quality of life in women with childbirth trauma. 相似文献
68.
69.
70.
Regina-Maria Renner Anna de Guzman Dalia Brahmi 《International journal of gynaecology and obstetrics》2014