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Surgical Samples (surgical + sample)
Selected AbstractsSampling variability of liver fibrosis in chronic hepatitis CHEPATOLOGY, Issue 6 2003Pierre Bedossa M.D. Fibrosis is a common endpoint of clinical trials in chronic hepatitis C, and liver biopsy remains the gold standard for fibrosis evaluation. However, variability in the distribution of fibrosis within the liver is a potential limitation. Our aim was to assess the heterogeneity of liver fibrosis and its influence on the accuracy of assessment of fibrosis with liver biopsy. Surgical samples of livers from patients with chronic hepatitis C were studied. Measurement of fibrosis was performed on the whole section by using both image analysis and METAVIR score (reference value). From the digitized image of the whole section, virtual biopsy specimens of increasing length were produced. Fibrosis was assessed independently on each individual virtual biopsy specimen. Results were compared with the reference value according to the length of the biopsy specimen. By using image analysis, the coefficient of variation of fibrosis measurement with 15-mm long biopsy specimens was 55%; and for biopsy specimens of 25-mm length it was 45%. By using the METAVIR scoring system, 65% of biopsies 15 mm in length were categorized correctly according to the reference value. This increased to 75% for a 25-mm liver biopsy specimen without any substantial benefit for longer biopsy specimens. Sampling variability of fibrosis is a significant limitation in the assessment of fibrosis with liver biopsy. In conclusion, this study suggests that a length of at least 25 mm is necessary to evaluate fibrosis accurately with a semiquantitative score. Sampling variability becomes a major limitation when using more accurate methods such as automated image analysis. [source] Ribosomal DNA sequence analysis of mucosa-associated bacteria in Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 6 2004Tom Prindiville MD Abstract Background: Enteric bacteria are implicated in the pathogenesis of Crohn's disease (CD); however, no specific causative organisms have been identified. Aims: This study was undertaken to correlate disease activity with changes in intestinal biota in patients with CD. Subjects: Ribosomal DNA analysis was used to explore the composition of the intestinal biota in patients with (1) CD undergoing colonoscopy, (2) CD undergoing surgical resection, and (3) no inflammatory bowel disease. Methods: Primers targeting bacterial 16S ribosomal DNA (rDNA) were used to amplify bacterial DNA associated with active CD lesions, comparable normal tissue from patients with CD, and normal control tissue. Each amplicon was cloned. Seven hundred thirty-nine rDNA clones were sequenced from 16 biopsies from CD patients, 15 surgical samples, and 10 biopsies from normal control patients. Results: Known extracellular or intracellular pathogens were not found. No rDNA sequence, phylogenetic group, or subgroup was consistently associated with CD lesions compared with normal tissues from the same patients. Colonic biopsies from CD-afflicted patients compared with biopsies from normal control subjects had an increase in facultative bacteria; in small bowel, CD patients had an increase in the Ruminococcus gnavus subgroup with a decrease in the Clostridium leptum and Prevotella nigrescens subgroups. However, differences in small bowel may have reflected individual variation rather than disease association. Surgical samples showed differences when compared with biopsy-derived samples. Conclusions: These findings suggest that CD is not caused by invasive pathogens associated specifically with the sites of lesions but that dysbiosis exists in this condition. [source] Expression of osteopontin in chronic rhinosinusitis with and without nasal polypsALLERGY, Issue 1 2009X. Lu Background:, Osteopontin (OPN) is a multifunctional 34-kDa extracellular matrix protein that can influence the inflammatory process. However, the presence of OPN in human sinonasal mucosa and its roles in the inflammatory process of chronic rhinosinusitis (CRS) are not clear. This study investigated the expression of OPN in human sinonasal mucosa, its cytokine-driven expression regulation, and its effect on cytokine production in sinonasal mucosa. Methods:, Surgical samples were investigated by means of quantitative reverse transcriptase polymerase chain reaction for evaluation of OPN messenger RNA (mRNA) expression, and the presence and location of OPN protein expression were analyzed using immunohistochemistry. Furthermore, nasal explant culture was used to investigate the mutual regulatory interactions between interferon (IFN)-,, interleukin (IL)-4, IL-5, IL-13, IL-1,, and tumor necrosis factor (TNF)-, and OPN in sinonasal mucosa. Results:, Osteopontin expression was significantly upregulated in CRS tissues compared with control tissues. There was a further significant increase of OPN expression in patients with nasal polyps (NPs) and asthma. Immunohistochemistry revealed positive staining of OPN in epithelial cells, submucosal glands, infiltrating cells, and extracellular matrix. Osteopontin mRNA was induced by IFN-,, IL-1,, and TNF-,, but inhibited by IL-4 and IL-13. On the contrary, OPN induced IFN-,, IL-4, IL-5, IL-13, IL-1,, and TNF-, production in sinonasal mucosa. Conclusions:, The expression of OPN is upregulated in CRS. The mutual regulatory interactions between OPN and inflammatory cytokines suggest that OPN may play an important role in the pathogenesis of CRS. [source] Nasal polyps in patients with and without cystic fibrosis: a differentiation by innate markers and inflammatory mediatorsCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2005S. Claeys Summary Background The dysfunction of the mucosal interface of the upper respiratory tract in cystic fibrosis (CF) patients is clinically visible by the development of nasal polyps (NP) at a young age. Innate defence markers and inflammatory mediators in NP from patients with CF were compared with non-cystic fibrosis nasal polyps (non-CF-NP) to determine a possible different immunological background in macroscopically similar tissue. Methods Surgical samples were obtained from patients with non-CF-NP, cystic fibrosis patients with nasal polyps (CF-NP) and control patients (CO). With real time PCR, the mRNA expression of human , defensins (HBD) 2 and 3, toll-like receptors (TLR) 2 and 4 and the macrophage mannose receptor (MMR) were measured. On homogenates of the surgical samples eotaxin, myeloperoxidase (MPO), IL-5 and IL-8 protein content was measured using commercial ELISA kits; IgE and eosinophilic cationic protein (ECP) were measured by the Unicap system. Results In CF-NP we found a statistically significant higher mRNA expression of HBD 2 compared with non-CF-NP and CO and of TLR 2 compared with non-CF-NP. In the non-CF-NP group, MMR mRNA expression was significantly elevated compared with CO and CF-NP. For TLR 4 mRNA expression no statistically significant differences were found between groups. IL-5 was below detection level in all CO and CF-NP, but was measurable in 80% of the non-CF-NP. MPO and IL-8 concentrations were significantly higher in CF-NP compared with CO and non-CF-NP, whereas ECP, eotaxin and IgE were significantly higher in the non-CF-NP group. Conclusions We here demonstrate that CF-NP and non-CF-NP not only differ in terms of inflammatory mediator profile, but also in terms of innate markers. [source] Localization of the A kinase anchoring protein AKAP79 in the human hippocampusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2000Attila Sík Abstract The phosphorylation state of the proteins, regulated by phosphatases and kinases, plays an important role in signal transduction and long-term changes in neuronal excitability. In neurons, cAMP-dependent protein kinase (PKA), protein kinase C (PKC) and calcineurin (CN) are attached to a scaffold protein, A kinase anchoring protein (AKAP), thought to anchor these three enzymes to specific sites of action. However, the localization of AKAP, and the predicted sites of linked phosphatase and kinase activities, are still unknown at the fine structural level. In the present study, we investigated the distribution of AKAP79 in the hippocampus from postmortem human brains and lobectomy samples from patients with intractable epilepsy, using preembedding immunoperoxidase and immunogold histochemical methods. AKAP79 was found in the CA1, presubicular and subicular regions, mostly in pyramidal cell dendrites, whereas pyramidal cells in the CA3, CA2 regions and dentate granule cells were negative both in postmortem and in surgical samples. In some epileptic cases, the dentate molecular layer and hilar interneurons also became immunoreactive. At the subcellular level, AKAP79 immunoreactivity was present in postsynaptic profiles near, but not attached to, the postsynaptic density of asymmetrical (presumed excitatory) synapses. We conclude that the spatial selectivity for the action of certain kinases and phosphatases regulating various ligand- and voltage-gated channels may be ensured by the selective presence of their anchoring protein, AKAP79, at the majority of glutamatergic synapses in the CA1, but not in the CA2/CA3 regions, suggesting profound differences in signal transduction and long-term synaptic plasticity between these regions of the human hippocampus. [source] Ribosomal DNA sequence analysis of mucosa-associated bacteria in Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 6 2004Tom Prindiville MD Abstract Background: Enteric bacteria are implicated in the pathogenesis of Crohn's disease (CD); however, no specific causative organisms have been identified. Aims: This study was undertaken to correlate disease activity with changes in intestinal biota in patients with CD. Subjects: Ribosomal DNA analysis was used to explore the composition of the intestinal biota in patients with (1) CD undergoing colonoscopy, (2) CD undergoing surgical resection, and (3) no inflammatory bowel disease. Methods: Primers targeting bacterial 16S ribosomal DNA (rDNA) were used to amplify bacterial DNA associated with active CD lesions, comparable normal tissue from patients with CD, and normal control tissue. Each amplicon was cloned. Seven hundred thirty-nine rDNA clones were sequenced from 16 biopsies from CD patients, 15 surgical samples, and 10 biopsies from normal control patients. Results: Known extracellular or intracellular pathogens were not found. No rDNA sequence, phylogenetic group, or subgroup was consistently associated with CD lesions compared with normal tissues from the same patients. Colonic biopsies from CD-afflicted patients compared with biopsies from normal control subjects had an increase in facultative bacteria; in small bowel, CD patients had an increase in the Ruminococcus gnavus subgroup with a decrease in the Clostridium leptum and Prevotella nigrescens subgroups. However, differences in small bowel may have reflected individual variation rather than disease association. Surgical samples showed differences when compared with biopsy-derived samples. Conclusions: These findings suggest that CD is not caused by invasive pathogens associated specifically with the sites of lesions but that dysbiosis exists in this condition. [source] Ultrastructural localization of glycodelin oligosaccharides Le-x and Le-y in human seminal vesicles by immunogold stainingJOURNAL OF ANATOMY, Issue 3 2007M. Piludu Abstract Histo-blood group antigens Le-x and Le-y are oligosaccharidic terminals that characterize many glycoproteins in the human tissues. In seminal plasma, they are expressed as part of the so-called glycodelin S, which is suggested to regulate sperm capacitation/decapacitation. It has recently been demonstrated that the core protein of glycodelin S is secreted by seminal vesicles. Here we show that epithelial cells of human seminal vesicles also release the Le-x and Le-y antigens. The presence of these substances in secretory material was revealed by means of an immunogold staining method in normal surgical samples. The results suggest that glycodelin S is secreted by seminal vesicles in its finished glycosylated form. Moreover, antigen reactivity was also revealed associated with plasma membranes. [source] Vascular endothelial growth factor (VEGF)-induced angiogenesis in herniated disc resorptionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2002Hirotaka Haro Abstract Intervertebral disc herniation is a major cause of low back pain and sciatica. Spontaneous resorption of herniated disc (HD) is frequently detected by magnetic resonance imaging (MRI). Marked infiltration by macrophages and neo-vascularization are observed upon histogical examination of HD. In addition, enhanced MRI studies suggest that HD resorption occurs more frequently in those completely exposed to the epidural space and that this correlates with their degree of vascularization. We have postulated that the angiogenic factor, vascular endothelial growth factor (VEGF), may be implicated in the neo-vascularization of HD tissues. Here we demonstrate that VEGF and its receptors VEGFR-1 and VEGFR-2 are expressed in human surgical samples of HD. Using a co-culture system comprised of murine peritoneal macrophages and intervertebral disc tissue as a model of the acute phase of HD developed previously, an increase in macrophage VEGF protein and mRNA expression was observed upon exposure to disc tissue. Tumor necrosis factor alpha (TNF-,) was required for this induction of VEGF. Use of a novel angiogenesis assay revealed that addition of the conditioned media from the co-culture system resulted in an increase of vascular tubule formation. This effect was strongly inhibited by anti-VEGF antibody, but augmented by recombinant VEGF. We conclude that VEGF induction, under the co-culture conditions tested can result in neo-vascularization of intervertebral disc tissue and may thus play a role in the resorption of HD. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Oncogenic and ligand-dependent activation of KIT/PDGFRA in surgical samples of imatinib-treated gastrointestinal stromal tumours (GISTs),THE JOURNAL OF PATHOLOGY, Issue 1 2009T Negri Abstract As the range of receptor tyrosine kinase (RTK) inhibitors widens, a detailed understanding of the activating mechanisms of KIT/platelet-derived growth factor receptor (PDGFR)A and the related downstream pathways involved in the development and maintenance of GISTs is becoming increasingly important. We analysed areas with different histological response ratios in surgical specimens taken from imatinib-treated and untreated GIST patients in order to investigate KIT and PDGFRA expression/activation, the presence of their cognate ligands and the activation of downstream signalling, by means of biochemistry, immunohistochemistry and flow cytometry. All of the cases showed KIT and PDGFRA co-expression. In addition to the oncogenic activation of mutated receptors, activation of wild-type KIT and wild-type PDGFRA, sustained by heterodimerization and an autocrine,paracrine loop, was demonstrated by the presence of their specific ligands, stem cell factor (SCF) and PDGFA. To confirm RTK activation further, all of the samples (including those with the highest regression ratios) were investigated for downstream effectors, and all proved to have activated downstream signalling. The results show that after the mutated receptors are switched off, heterologous wild-type receptors become important in imatinib-treated GISTs as a means of maintaining signalling activation. Taken together, our findings suggest that drugs targeting wild-type receptors should be tested in imatinib-treated GIST patients. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] P-cadherin expression reduced in squamous cell carcinoma of the oral cavityCANCER, Issue 5 2005An indicator of poor prognosis Abstract BACKGROUND The loss of cadherin expression has been shown to correlate to the invasion and metastasis of many types of carcinomas. The purpose of the current study was to evaluate whether the impaired expression of E-cadherin (E-cad) and P-cadherin (P-cad) correlated with the clinical evolution and prognosis of oral squamous cell carcinoma (OSCC). METHODS The authors used immunohistochemical methods to analyze the expression pattern of E-cad and P-cad in healthy oral mucosa, in oral carcinoma in situ (CIS), and in surgical samples of 50 patients with the early stages (Stages I,II) of OSCC. RESULTS E-cad showed weak expression in the basal layer of the healthy oral mucosa and reduced expression in patients with oral CIS. P-cad expression was conserved on the basal and suprabasal layers of the healthy mucosa and, also, in the CIS. In the group of patients with OSCC, univariate analysis demonstrated that reduced expression of E-cad or P-cad correlated significantly with locoregional disease recurrence in the follow-up (P = 0.03 and P = 0.01, respectively). However, only the reduction in the expression of P-cad emerged as an independent prognostic marker in the multivariate analysis (P = 0.04, hazard ratio = 8.06). CONCLUSIONS These findings suggested that a decrease in E-cad and/or P-cad expression may contribute to the invasive potential of early OSCC. According to the current data, P-cad expression may be a potential independent prognostic factor in patients with OSCC. Cancer 2005. © 2005 American Cancer Society. [source] Predictive value of pentagastrin test for preoperative differential diagnosis between C-cell hyperplasia and medullary thyroid carcinoma in patients with moderately elevated basal calcitonin levelsCLINICAL ENDOCRINOLOGY, Issue 1 2010F. Milone Summary Background and Objectives, Medullary thyroid carcinoma (MTC) is a calcitonin (CT)-secreting neuroendocrine tumour originating from thyroid C cells. Serum CT concentrations are helpful in the early detection of MTC, while it is still unclear whether they can be used also for the differential diagnosis between MTC and C-cell hyperplasia (CCH), a precancerous condition in familial MTCs but with unclear clinical significance in sporadic MTCs. Nowadays, surgery is recommended in all patients with basal or pentagastrin (PG)-stimulated CT value of 100 pg/ml or more, without discriminating if they are affected with MTC or CCH only. The objective of this study was to investigate the utility of the PG test for CT in distinguishing CCH from MTC before surgery. Patients and Methods, Sixteen of 20 patients with thyroid nodules and basal CT levels between 15 and 100 ng/l had a positive PG test (>100 ng/l PG CT peak) and form the basis of the data analysis. A diagnosis of MTC was histologically proved on surgical samples in seven patients and of CCH in nine other patients. Four patients with neither FNAB nor PG test consistent with a diagnosis of MTC did not undergo thyroidectomy. Results, A peak of CT of 275 ng/l after PG was able to significantly distinguish patients with MTC from patients with CCH, with 100% sensitivity and 89% specificity (P = 0·002). PG-stimulated calcitonin levels >275 ng/l had a positive predictive value (PPV) value for diagnosis of MTC of 100%, and PG-stimulated calcitonin levels <275 had a PPV for the diagnosis of CCH of 89%. Conclusions, A CT cut-off after PG of 275 ng/l is suggested to be highly predictive in distinguishing CCH from MTC before surgery, and this may be helpful in selecting patients for thyroid surgery. [source] | |||||||||||||