946 resultados para Fos immunoreactivity


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The transforming growth factor-beta (TGFbeta) superfamily and its downstream effector genes are key regulators of epithelial homeostasis. Altered expression of these genes may be associated with malignant transformation of the prostate gland. The cDNA array analysis of differential expression of the TGFbeta superfamily and functionally related genes between patient-matched noncancerous prostate (NP) and prostate cancer (PC) bulk tissue specimens highlighted two genes, namely TGFbeta-stimulated clone-22 (TSC-22) and Id4. Verification of their mRNA expression by real-time PCR in patient-matched NP and PC bulk tissue, in laser-captured pure epithelial and cancer cells and in NP and PC cell lines confirmed TSC-22 underexpression, but not Id4 overexpression, in PC and in human PC cell lines. Immunohistochemical analysis showed that TSC-22 protein expression in NP is restricted to the basal cells and colocalizes with the basal cell marker cytokeratin 5. In contrast, all matched PC samples lack TSC-22 immunoreactivity. Likewise, PC cell lines do not show detectable TSC-22 protein expression as shown by immunoblotting. TSC-22 should be considered as a novel basal cell marker, potentially useful for studying lineage determination within the epithelial compartment of the prostate. Conversely, lack of TSC-22 seems to be a hallmark of malignant transformation of the prostate epithelium. Accordingly, TSC-22 immunohistochemistry may prove to be a diagnostic tool for discriminating benign lesions from malignant ones of the prostate. The suggested tumour suppressor function of TSC-22 warrants further investigation on its role in prostate carcinogenesis and on the TSC-22 pathway as a candidate therapeutic target in PC.

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The heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been implicated in wound-healing processes of various tissues. However, it is not known whether HB-EGF may represent a factor implicated in overstimulated wound-healing processes of the retina during proliferative retinopathies. Therefore, we investigated whether human retinal pigment epithelial (RPE) cells, which are crucially involved in proliferative retinopathies, express and respond to HB-EGF. RPE cells express mRNAs for various members of the EGF-related growth factor family, among them for HB-EGF, as well as for the EGF receptors ErbB1, -2, -3, and -4. The gene expression of HB-EGF is stimulated in the presence of transforming and basic fibroblast growth factors and by oxidative stress and is suppressed during chemical hypoxia. Exogenous HB-EGF stimulates proliferation and migration of RPE cells and the gene and protein expression of the vascular endothelial growth factor (VEGF). HB-EGF activates at least three signal transduction pathways in RPE cells including the extracellular signal-regulated kinases (involved in the proliferation-stimulating action of HB-EGF), p38 (mediates the effects on chemotaxis and secretion of VEGF), and the phosphatidylinositol-3 kinase (necessary for the stimulation of chemotaxis). In epiretinal membranes of patients with proliferative retinopathies, HB-EGF immunoreactivity was partially colocalized with the RPE cell marker, cytokeratins; this observation suggests that RPE cell-derived HB-EGF may represent one factor that drives the uncontrolled wound-healing process of the retina. The stimulating effect on the secretion of VEGF may suggest that HB-EGF is also implicated in the pathological angiogenesis of the retina.

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We report on clinicopathological findings in two cases of rosette-forming glioneuronal tumor of the fourth ventricle (RGNT) occurring in females aged 16 years (Case 1) and 30 years (Case 2). Symptoms included vertigo, nausea, cerebellar ataxia, as well as headaches, and had been present for 4-months and 1 week, respectively. Magnetic resonance imaging (MRI) indicated a cerebellar-based tumor of 1.8cm (Case 1) and 5cm (Case 2) diameter each, bulging into the fourth ventricle. Case 2 involved a cyst-mural-nodule configuration. In both instances, the solid component appeared isointense on T(1) sequences, hyperintense in the T(2) mode, and enhanced moderately. Gross total resection was achieved via suboccipital craniotomy. However, functional recovery was disappointing in Case 1. On microscopy, both tumors comprised an admixture of low-grade astrocytoma interspersed with circular aggregates of synaptophysin-expressing round cells harboring oligodendrocyte-like nuclei. The astrocytic moiety in Case 1 was nondescript, and overtly pilocytic in Case 2. The architecture of neuronal elements variously consisted of neurocytic rosettes, of pseudorosettes centered on a capillary core, as well as of concentric ribbons along irregular lumina. Gangliocytic maturation, especially "floating neurons", or a corresponding immunoreactivity for neurofilament protein was absent. Neither of these populations exhibited atypia, mitotic activity, or a significant labeling for MIB-1. Cerebellar parenchyma included in the surgical specimen did not reveal any preexisting malformative anomaly. Despite sharing some overlapping histologic traits with dysembryoplastic neuroepithelial tumor (DNT), the presentation of RGNT with respect to both patient age and location is consistent enough for this lesion to be singled out as an autonomous entity.

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The amygdala has been studied extensively for its critical role in associative fear conditioning in animals and humans. Noxious stimuli, such as those used for fear conditioning, are most effective in eliciting behavioral responses and amygdala activation when experienced in an unpredictable manner. Here, we show, using a translational approach in mice and humans, that unpredictability per se without interaction with motivational information is sufficient to induce sustained neural activity in the amygdala and to elicit anxiety-like behavior. Exposing mice to mere temporal unpredictability within a time series of neutral sound pulses in an otherwise neutral sensory environment increased expression of the immediate-early gene c-fos and prevented rapid habituation of single neuron activity in the basolateral amygdala. At the behavioral level, unpredictable, but not predictable, auditory stimulation induced avoidance and anxiety-like behavior. In humans, functional magnetic resonance imaging revealed that temporal unpredictably causes sustained neural activity in amygdala and anxiety-like behavior as quantified by enhanced attention toward emotional faces. Our findings show that unpredictability per se is an important feature of the sensory environment influencing habituation of neuronal activity in amygdala and emotional behavior and indicate that regulation of amygdala habituation represents an evolutionary-conserved mechanism for adapting behavior in anticipation of temporally unpredictable events.

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AIMS: To evaluate the expression of matrix metalloproteinase-19 (MMP-19) in oropharyngeal squamous cell carcinoma along with its association with structural features of invasiveness. To investigate whether MMP-19 expression correlates with lymphatic or systemic metastasis and prognosis in patients who have received definitive radiotherapy. METHODS AND RESULTS: The histological evaluation of the invasive front was based on Bryne's malignancy grading system. We correlated the immunohistochemical expression pattern with morphological parameters which characterize tumor invasiveness such as keratinization, nuclear polymorphism, invasion pattern, and the host inflammatory response. Local immunoreactivity for MMP-19 was positively correlated with tumor invasiveness as reflected in its structural characteristics and the degree of nuclear polymorphism, and negatively correlated with the inflammatory response of the host. No correlation existed between MMP-19 expression and clinicopathological features (TNM stage, grade of differentiation) or a patient''s outcome and prognosis. CONCLUSIONS: This latter finding probably reflects the unique change for MMPs from high immunoreactivity within healthy tissue areas and non-invasive tumor parts, through absence in the least invasive neoplastic regions, to strong re-expression at a highly invasive front of the same tumor. Our findings indicate that MMP-19 can be used as a marker for tumor invasiveness in patients with oropharyngeal squamous cell carcinoma.

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Zymosan-induced peritonitis is associated with an increased production of reactive nitrogen oxides that may contribute to the often-observed failure of multiple organ systems in this model of acute inflammation. Quantitative biochemical evidence is provided for a marked 13-fold increase in protein-bound 3-nitrotyrosine (NTyr), a biomarker of reactive nitrogen oxides, in liver tissue of zymosan-treated rats. In order to investigate the localization of NTyr in this affected tissue, a monoclonal antibody, designated 39B6, was raised against 3-(4-hydroxy-3-nitrophenylacetamido) propionic acid-bovine serum albumin conjugate and its performance characterized. 39B6 was judged by competition ELISA to be approximately 2 orders of magnitude more sensitive than a commercial anti-NTyr monoclonal antibody. Binding characteristics of 39B6 were similar, but not identical, to that of a commercial affinity-purified polyclonal antibody in ELISA and immunohistochemical analyses. Western blot experiments revealed high specificity of 39B6 against NTyr and increased immunoreactivity of specific proteins from liver tissue homogenates of zymosan-treated rats. Immunohistochemical analysis of liver sections indicated a marked zymosan-induced increase in immunofluorescent staining, which was particularly intense in or adjacent to nonparenchymal cells, but not in the parenchymal cells of this tissue. Quantitative analysis of fractions enriched in these cell populations corroborated the immunofluorescent data, although the relative amounts detected in response to zymosan treatment was greatly reduced compared to whole liver tissue. These results demonstrate the high specificity of the newly developed antibody and its usefulness in Western blot and immunohistochemical analysis for NTyr, confirm the presence of NTyr by complementary methods, and suggest the possible involvement of reactive nitrogen oxides in hepatic vascular dysfunction.

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OBJECTIVE: Vasa vasorum (VV) have been implicated to play a role in the pathogenesis of atherosclerosis. This study was designed to describe the distribution of VV density in different vascular beds in humans and to investigate the association between VV density and the known distribution of atherosclerosis in human arteries. METHODS: Forty-two human arteries, harvested at autopsy or after explantation, were analyzed by three-dimensional microscopic-computed tomography (micro-CT). VV density, endothelial-surface-fraction (Sigma VV endothelial-surface-area/vessel-wall-volume) and vascular-area-fraction (Sigma VV area/vessel-wall-area) were calculated for coronary, renal and femoral arteries. Representatively five coronary, renal and femoral arteries were stained for endothelial cells (von Willebrand-Factor), macrophages (CD68), vascular endothelial growth factor (VEGF) and collagen (Sirius Red). RESULTS: Coronary arteries showed a higher VV density compared to renal and femoral arteries (2.12+/-0.26 n/mm(2) versus 0.61+/-0.06 n/mm(2) and 0.66+/-0.11 n/mm(2); P<0.05 for both) as well as a higher endothelial-surface-fraction and vascular-area-fraction. Histology showed a positive correlation between histologically derived VV density and CD68-positive cells/area (r=0.54, P<0.01), VEGF-immunoreactivity/area (r=0.55, P<0.01) and a negative correlation between VV density and collagen I content (r=0.66, P<0.05). CONCLUSION: This micro-CT study highlights a higher VV density in coronary than in peripheral arteries, supporting the relation between VV density and the susceptibility to atherosclerosis in different vascular beds in humans.

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Nitric oxide mediates a wide array of cellular functions in many tissues. It is generated by three known isoforms of nitric oxide synthases (NOS). Recently, the endothelial isoform, NOSIII, was shown to be abundantly expressed in the rat thyroid gland and its expression increased in goitrous glands. In this study, we analyzed whether NOSIII is expressed in human thyroid tissue and whether levels of expression vary in different states of thyroid gland function. Semiquantitative RT-PCR was used to assess variations in NOSIII gene expression in seven patients with Graves' disease, one with a TSH-receptor germline mutation and six hypothyroid patients (Hashimoto's thyroiditis). Protein expression and subcellular localization were determined by immunohistochemistry (two normal thyroids, five multinodular goiters, ten hyperthyroid patients and two hypothyroid patients). NOSIII mRNA was detected in all samples: the levels were significantly higher in tissues from hyperthyroid patients compared with euthyroid and hypothyroid patients. NOSIII immunoreactivity was detected in vascular endothelial cells, but was also found in thyroid follicular cells. In patients with Graves' disease, the immunostaining was diffusely enhanced in all follicular cells. A more intense signal was observed in toxic adenomas and in samples obtained from a patient with severe hyperthyroidism due to an activating mutation in the TSH receptor. In multinodular goiters, large follicles displayed a weak signal whereas small proliferative follicles showed intense immunoreactivity near the apical plasma membrane. In hypothyroid patients, NOSIII immunoreactivity was barely detectable. In summary, NOSIII is expressed both in endothelial cells and thyroid follicular cells. The endothelial localization of NOSIII is consistent with a role for nitric oxide in the vascular control of the thyroid. NOSIII expression in thyroid follicular cells and the variations in its immunoreactivity suggest a possible role for nitric oxide in thyrocyte function and/or growth.

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In contrast to the current belief that angiotensin II (Ang II) interacts with the sympathetic nervous system only as a circulating hormone, we document here the existence of endogenous Ang II in the neurons of rat and human sympathetic coeliac ganglia and their angiotensinergic innervation with mesenteric resistance blood vessels. Angiotensinogen - and angiotensin converting enzyme-mRNA were detected by using quantitative real time polymerase chain reaction in total RNA extracts of rat coeliac ganglia, while renin mRNA was untraceable. Cathepsin D, a protease responsible for cleavage beneath other substrates also angiotensinogen to angiotensin I, was successfully detected in rat coeliac ganglia indicating the possibility of existence of alternative pathways. Angiotensinogen mRNA was also detected by in situ hybridization in the cytoplasm of neurons of rat coeliac ganglia. Immunoreactivity for Ang II was demonstrated in rat and human coeliac ganglia as well as with mesenteric resistance blood vessels. By using confocal laser scanning microscopy we were able to demonstrate the presence of angiotensinergic synapses en passant along side of vascular smooth muscle cells. Our findings indicate that Ang II is synthesized inside the neurons of sympathetic coeliac ganglia and may act as an endogenous neurotransmitter locally with the mesenteric resistance blood vessels.

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This study investigated the anatomical consequences of a photoreceptor toxin, iodoacetic acid (IAA), in the rabbit retina. Retinae were examined 2 weeks, 1, 3, and 6 months after systemic IAA injection. The retinae were processed using standard histological methods to assess the gross morphology and topographical distribution of damage, and by immunohistochemistry to examine specific cell populations in the retina. Degeneration was restricted to the photoreceptors and was most common in the ventral retina and visual streak. In damaged regions, the outer nuclear layer was reduced in thickness or eliminated entirely, with a concomitant loss of immunoreactivity for rhodopsin. However, the magnitude of the effect varied between animals with the same IAA dose and survival time, suggesting individual differences in the bioavailability of the toxin. In all eyes, the inner retina remained intact, as judged by the thickness of the inner nuclear layer, and by the pattern of immunoreactivity for protein kinase C-alpha (rod bipolar cells) and calbindin D-28 (horizontal cells). Müller cell stalks became immunoreactive for glial fibrillary acidic protein (GFAP) even in IAA-treated retinae that had no signs of cell loss, indicating a response of the retina to the toxin. However, no marked hypertrophy or proliferation of Müller cells was observed with either GFAP or vimentin immunohistochemistry. Thus the selective, long lasting damage to the photoreceptors produced by this toxin did not lead to a reorganization of the surviving cells, at least with survival as long as 6 months, in contrast to the remodeling of the inner retina that is observed in inherited retinal degenerations such as retinitis pigmentosa and retinal injuries such as retinal detachment.

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Dopamine deficiency in Parkinson's disease leads to numerous molecular changes in basal ganglia. However, the consequences of these changes on the motor cortex remain unclear. Here we show that the immunoreactivity of parvalbumin, which is expressed in GABAergic interneurons, increases in the primary motor cortex of parkinsonian rats. This increase can be reversed by a subsequent lesion of the subthalamic nucleus. These results suggest that dopamine deficiency induces reversible changes in GABAergic cortical cells, which might be linked with parkinsonian symptoms.

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CONTEXT: The success of pancreatic islet transplantation depends largely on the capacity of the islet graft to survive the initial phase immediately after transplantation until revascularization is completed. Endothelin-1 (ET-1) is a strong vasoconstrictor which has been involved in solid organ graft failure but is also known to be a potent mitogenic/anti-apoptotic factor which could also potentially enhance the survival of the transplanted islets. OBJECTIVE: Characterization of the endothelin system with regard to a potential endothelin agonist/antagonist treatment. DESIGN: Regulated expression of the endothelin system in human and rat pancreatic islets and beta-cell lines was assessed by means of immunohistochemistry, competition binding studies, western blot, RT-PCR, real-time PCR and transplant studies. RESULTS: ET-1, ETA- and ETB-receptor immunoreactivity was identified in the endocrine cells of human and rat pancreatic islets. The corresponding mRNA was detectable in rat beta-cell lines and isolated rat and human pancreatic islets. Competition binding studies on rat islets revealed binding sites for both receptor types. ET-1 stimulated the phosphorylation of mitogen-activated protein kinase, which was prevented by ETA- and ETB-receptor antagonists. After exposure to hypoxia equal to post-transplant environment oxygen tension, mRNA levels of ET-1 and ETB-receptor of human islets were robustly induced whereas ETA-receptor mRNA did not show significant changes. Immunostaining signals for ET-1 and ETA-receptor of transplanted rat islets were markedly decreased when compared to native pancreatic sections. CONCLUSIONS: In pancreatic islets, ET-1 and its receptors are differentially expressed by hypoxia and after transplantation. Our results provide the biological basis for the study of the potential use of endothelin agonists/antagonists to improve islet transplantation outcome.

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BACKGROUND: Psoriasis is a chronic immune-mediated skin disease, in which interleukins 12 and 23 have been postulated to play a critical role. However, the cellular source of these cytokines in psoriatic lesions are still poorly defined and their relative contribution in inducing skin inflammation has been discussed controversially. OBJECTIVES: To investigate immunoreactivity of the bioactive forms of IL-12 and IL-23 in plaque psoriasis and to characterize the dendritic cell (DC) and macrophage subsets responsible for the production of these cytokines. METHODS: Immunohistochemistry was performed on normal skin (n=11) as well as non-lesional (n=11) and lesional (n=11) skin of patients with plaque psoriasis using monoclonal antibodies targeting the bioactive forms of IL-12 (IL-12p70) and IL-23 (IL-23p19/p40) on serial cryostat sections using the alkaline phosphatase-antialkaline phosphatase. Co-localization of IL-12 and IL-23 with different dendritic cells and macrophage cell markers (CD1a, CD11c, CD14, CD32, CD68, CD163, CD208/DC-LAMP) was performed using double immunofluorescence staining. RESULTS: Immunoreactivity for IL-12 and IL-23 was significantly enhanced in lesional psoriatic skin as compared to non-lesional and normal skin. No difference was observed between IL-12 and IL-23 immunoreactivity in any skin types. Both IL-12 and IL-23 immunoreactivity was readily detected mainly in CD11c+, CD14+, CD32+, CD68+ and some CD163+, DC-LAMP+ cells. IL-12 and occasionally IL-23 were also found in some CD1a+ dendritic cells. In addition, an enhanced expression mainly of IL-23 was observed in keratinocytes. CONCLUSIONS: Bioactive forms of IL-12 and IL-23 are highly expressed in various DC and macrophage subsets and their marked in situ production suggest that both cytokines have crucial pathogenic role in psoriasis.

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CCAAT/enhancer binding protein alpha (CEBPA) mutations in AML are associated with favourable prognosis and are divided into N- and C-terminal mutations. The majority of AML patients have both types of mutations. We assessed the prognostic significance of single (n=7) and double (n=12) CEBPA mutations among 224 AML patients. Double CEBPA mutations conferred a decisively favourable overall (P=0.006) and disease-free survival (P=0.013). However, clinical outcome of patients with single CEBPA mutations was not different from CEBPA wild-type patients. In a multivariable analysis, only double -- but not single -- CEBPA mutations were identified as independent prognostic factors. These findings indicate heterogeneity within AML patients with CEBPA mutations.

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BACKGROUND: An increasing body of evidence suggests a possible role of suburothelial myofibroblasts (MFs) in bladder mechanosensation and in the pathophysiology of detrusor overactivity (DO). OBJECTIVE: To determine whether markers of MFs, including gap junction protein connexin43 (Cx43) and c-kit have altered immunohistochemical expression in the suburothelium of patients with neurogenic DO (NDO) or idiopathic DO (IDO) and whether this is affected by successful treatment of DO with botulinum neurotoxin type A (BoNTA). DESIGN, SETTING, AND PARTICIPANTS: Patients with NDO (n=10) or IDO (n=11) were treated in a single-centre, open-label study of intradetrusor BoNTA injections. Control tissue was obtained from 10 patients undergoing pelvic-floor repair procedures who had no overactive bladder (OAB) symptoms. This study is registered with ClinicalTrials.gov, number NCT00662064. INTERVENTIONS: Bladder biopsies performed with flexible cystoscopes were obtained from control subjects and from NDO and IDO patients before BoNTA treatment and at 4 wk and 16 wk after treatment. They were studied with quantitative immunofluorescence using antibodies to connexin 43 (Cx43), vimentin, and c-kit. MEASUREMENTS: Differences in Cx43, vimentin, and c-kit immunoreactivity between control subjects and NDO or IDO patients (primary outcomes). Changes in NDO or IDO, Cx43 immunoreactivity, and c-kit immunoreactivity after BoNTA treatment (secondary outcomes). RESULTS AND LIMITATIONS: Cx43 immunoreactivity was increased in both IDO and NDO patients compared to controls, but remained unchanged after BoNTA treatment. C-kit immunoreactivity was similar in NDO/IDO patients and controls and remained unchanged after BoNTA treatment. CONCLUSIONS: Increased gap junction formation in the suburothelium has been demonstrated in biopsies from humans with DO. It is hypothesised that this change could have a significant role in the pathogenesis of the detrusor abnormality. Successful treatment of NDO or IDO does not appear to be associated with changes in the expression of Cx43 or c-kit on suburothelial MFs.