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51.
Lillesaar C Eriksson C Johansson CS Fried K Hildebrand C 《Journal of neurocytology》1999,28(8):663-670
The mammalian tooth pulp becomes innervated by nociceptive and sympathetic axons relatively late during development, when part of the root has formed. In the adult, regenerating axons from an injured tooth nerve or sprouting axons from uninjured nerves in the vicinity rapidly reinnervate denervated tooth pulps. These observations indicate that tooth pulp tissue can use molecular factors to attract pulpal axons from local nerve trunks. The present study examines the hypothesis that these factors include nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and glial cell line derived neurotrophic factor (GDNF). Explants of trigeminal ganglia from neonatal rat pups showed a distinct neurite outgrowth when co-cultured with pulpal explants collected from molar teeth of 12-day old pups, or after application of a pulpal extract. Control cultures, containing single ganglionic explants, or explants co-cultured with heat-treated pulpal tissue, exhibited a sparse neurite outgrowth. Exogenous NGF and/or GDNF, but not exogenous BDNF, stimulated neurite outgrowth from ganglionic explants. Unexpectedly, application of antibodies against NGF, BDNF and/or GDNF to co-cultures of ganglionic and pulpal explants did not inhibit neuritogenesis. Control experiments showed that IgG molecules readily penetrate the gel used for culture and that even very high concentrations of NGF and GDNF antibodies in combination failed to block neurite growth. On the basis of these data we suggest that other as yet unknown neurite-promoting factors might be present and active in TG/pulpal co-cultures. 相似文献
52.
Hendrik Schimmelpenning Elina T. Eriksson Bo Franzén Anders Zetterberg Gert U. Auer 《Virchows Archiv : an international journal of pathology》1993,423(4):273-279
The expression of theS-phase associated, nuclear protein proliferating cell nuclear antigen (PCNA) was investigated in routinely paraffin-embedded surgical specimens from 209 breast cancer patients. Cytometric DNA assessments were performed on fine-needle aspirates, upon which the primary diagnosis of breast cancer had been based. The mean clinical follow-up was 16 years (range 13–20 years). The percentage of PCNA immunoreactive tumour cells ranged between less than 5 to 60% (mean value 13.34%). There was a direct association between PCNA expression, high histological tumour grade (p<0.01), and DNA aneuploidy (p=0.009). In a subgroup of 22 patients with near-diploid DNA distribution patterns the PCNA expression yielded additional prognostic information. Patients with tumours of near-diploid DNA histograms and more than 20% of PCNA immunoreactive neoplastic cells had a significantly worse clinical course, than patients with neardiploid tumours containing less than 20% PCNA immunoreactive cells (p=0.0001). In contrast, the PCNA immunoreactivity did not yield additional prognostic information for patients with distinctly diploid or highly aneuploid tumour variants. In a multivariate analysis comprising all 209 patients, nodal status (p<0.01), tumour size (p<0.01), and DNA ploidy (p<0.01) were found to have significant prognostic effect. The findings indicate that carcinomas characterised by high proliferative activity and near-diploid DNA distribution patterns can show rapid tumour progression. The combined assessment of the PCNA immunoreactivity and of the nuclear DNA content in routinely processed surgical specimens of breast cancer patients appears to be of prognostic value. 相似文献
53.
Stephan G. M. Meuwissen Anne Bosma Evert van Donk Reinier Waalewijn Gerard Pals Jan C. Pronk Aldur W. Eriksson Hendrik Mullink Chris J. L. M. Meijer 《Virchows Archiv : an international journal of pathology》1988,413(1):11-16
Summary No data are available on the localization of Pepsinogen A (PGA=PG I) and Pepsinogen C (PGC=PG II) positive cells in Barrett's epithelium. Endoscopic biopsy specimens were taken from the columnar epithelium from 23 patients (n=93), and in addition from the cardia from eight healthy control subjects (n=38). The tissue was stained by the immunoperoxidase technique with specific anti-pepsinogen antisera, and double immunostained for PGA and PGC. In the Barrett's epithelium PGA was found in 28 out of 93 biopsy specimens (30.1%) and PGC in 55 out of 93 (59.1%). Chief cells always stained both for PGA and PGC, while clear mucous cells were often PGA– and PGC+. PGA+ and PGC+ cells were found each in 100% of the biopsy specimens with fundic type epithelium, in 21.7% and 70.7% of biopsy specimens with junctional type, in 0% and 26.1% of biopsy specimens with specialized epithelium and in 12.5% and 43.5% of biopsy specimens with mixed junctional/specialized features respectively. Dysplastic epithelium stained always negatively with both anti-pepsinogen antisera. In most control cardia biopsy specimens PGA as well as PGC were demonstrable; occasionally clear mucous glands were PGA– and PGC+.It is concluded that pepsinogen-containing cells can be accurately identified in the Barrett's epithelium; their presence seems related to the histological cell type. Identification of pepsinogen positive cells may contribute to a more accurate morphological classification of the Barrett's epithelium.Presented in part at the Annual Meeting of the American Gastroenterological Association, San Francisco, May 1986 相似文献
54.
Genome of the European elk papillomavirus (EEPV) 总被引:1,自引:0,他引:1
The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%). 相似文献
55.
56.
Effects of HDL3 on the expression of matrix-degrading proteases in human endothelial cells 总被引:1,自引:0,他引:1
Norata GD Pellegatta F Hamsten A Catapano AL Eriksson P 《International journal of molecular medicine》2003,12(1):73-78
Modified lipoproteins have been suggested to modulate the expression of matrix-degrading proteases in the vascular wall. Since oxidized high density lipoprotein (HDL) has been found in atheromatous plaques and receptors for modified HDL are present on endothelial cells, we investigated the role of native and oxidized HDL3 on the expression of 35 proteases and their inhibitors in human endothelial cells using microarray analysis. Matrix metalloproteinase (MMP)-1, -2, -10, -13 and -14, tissue inhibitor of MMP (TIMP)-1, -2 and -3, cathepsin B and D, and cystatin C were expressed under basal conditions, of which MMP-10 and cystatin C expression have not been described before in endothelial cells. Native HDL3 increased MMP-1 and MMP-14 expression and decreased MMP-13 expression, whereas oxidized HDL3 increased PAI-1 and MMP-1 expression. The expression pattern was confirmed by quantitative real-time PCR. In summary, a large repertoire of matrix-degrading proteases is expressed in endothelial cells, an expression that can be modulated by native and oxidized HDL3. 相似文献
57.
Amir?R?RazaviEmail author Hans?Gill Olle?St?l Marie?Sundquist Sten?Thorstenson Hans??hlfeldt Nosrat?Shahsavar the South-East Swedish Breast Cancer Study Group 《BMC medical informatics and decision making》2005,5(1):29
Background
A common approach in exploring register data is to find relationships between outcomes and predictors by using multiple regression analysis (MRA). If there is more than one outcome variable, the analysis must then be repeated, and the results combined in some arbitrary fashion. In contrast, Canonical Correlation Analysis (CCA) has the ability to analyze multiple outcomes at the same time. 相似文献58.
COMT Gene Polymorphism Is Associated with Declarative Memory in Adulthood and Old Age 总被引:5,自引:0,他引:5
de Frias CM Annerbrink K Westberg L Eriksson E Adolfsson R Nilsson LG 《Behavior genetics》2004,34(5):533-539
Variation in memory performance is to a large extent explained by genes. In the prefrontal cortex, the catechol O-methyltransferase (COMT) gene is essential in the metabolic degradation of dopamine, a neurotransmitter implicated in cognitive functions. The present study examined the effect of a polymorphism in the COMT gene on individual differences and changes in memory in adulthood and old age. Tests assessing episodic and semantic memory were administered to 286 men (initially aged 35-85 years) from a random sample of the population (i.e., the Betula prospective cohort study) at two occasions followed over a 5-year period. Carriers of the Met/Met genotype (with low enzyme activity) performed better on episodic and semantic memory, as compared to carriers of the Val allele (with higher enzyme activity). Division of episodic memory into its recall and recognition components showed that the difference was specific to episodic recall, not recognition tasks; an effect that was observed across three age groups (middle-age, young-old, and old-old adults) and over a 5-year period. The COMT gene is a plausible candidate gene for memory functioning in adulthood and old age. 相似文献
59.
Immunobiology of human mesenchymal stem cells and future use in hematopoietic stem cell transplantation. 总被引:25,自引:0,他引:25
Mesenchymal stem cells (MSCs) may be derived from adult bone marrow, fat, and several fetal tissues. In vitro, MSCs can be expanded and have the capacity to differentiate into several mesenchymal tissues, such as bone, cartilage, and fat. They escape the immune system in vitro, and this may make them candidates for cellular therapy in an allogeneic setting. They also have immunomodulatory effects, inhibit T-cell proliferation in mixed lymphocyte cultures, prolong skin allograft survival, and may decrease graft-versus-host disease (GVHD) when cotransplanted with hematopoietic stem cells. MSCs induce their immunosuppressive effect via a soluble factor. Some candidates have been suggested, and various mechanisms have also been suggested, although contradictory data exist; this may be due to differences in the cells and systems tested. A major problem has been that it has been difficult to identify and isolate MSCs after transplantation in vivo. However, MSCs seem to enhance hematopoietic engraftment in recipients of autologous and allogeneic grafts. Recently, they were found to reverse grade IV acute GVHD of the gut and liver. No tolerance was induced, however. Controlled studies are warranted. Thus, in allogeneic stem cell transplantation, MSCs may be used for hematopoiesis enhancement, as GVHD prophylaxis, and for the treatment of severe acute GVHD. They are also of potential use in the treatment of organ transplant rejection and in autoimmune inflammatory bowel disorders where immunomodulation and tissue repair are needed. 相似文献
60.
M Rundgren H Jónasson B Appelgren S Eriksson L G Leksell 《Acta physiologica Scandinavica》1984,121(4):393-399
The renal arginine vasopressin (AVP) excretion in response to acute systemic hypotension induced by intravenous infusion of sodium nitroprusside (SNP) (30-40 micrograms/kg min-1) at different experiment intervals (0, 2, 4, 7 and greater than or equal to 12 days) was studied in the conscious hyperhydrated sheep. During the first post-infusion hour, 2.5 times more AVP was excreted in response to hypotension induced at greater than or equal to 12 day intervals than that observed at intervals of 0-7 days. No interexperimental time dependence of the AVP response to SNP infusion was seen with intervals of 0-7 days. The attenuated AVP release obtained with reduced experiment intervals (0-7 days) was accompanied by shorter antidiuresis and a less accentuated natriuresis during the post-hypotensive period in comparison to what was observed with greater than or equal to 12 day experiment intervals. There were no interval-dependent differences in maximal fall of mean arterial pressure, or onset and recovery of the hypotension induced by SNP administration. It is suggested that acute systemic hypotension causes such a massive AVP release that more than one week is needed for complete restoration of a releasable neurohypophyseal pool of the hormone. 相似文献