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Conventional Histology (conventional + histology)
Selected AbstractsModulation of the pathology of late xenograft rejection by PAF-antagonist UR-12670 in the hamster-to-rat liver xenotransplant model,APMIS, Issue 3 2003PAF antagonist alleviates xenogeneic rejection PAF antagonists have been used in xenotransplantation to alleviate the pathogenesis of hyperacute rejection. This study evaluated the ability of the PAF antagonist UR-12670 to improve graft function in late xenograft rejection (LXR) in an orthotopic liver xenotransplantation model, and the involvement of PAF (platelet activating factor) in this type of rejection. The recipients of a hamster xenograft received standard immunosuppression (tacrolimus 0.2 mg/kg/30 days, MMF 25 mg/kg/8 days). Study groups: group A, without UR-12670, group B, UR-12670 (20 mg/kg/8 d) and group C, continuous administration of UR-12670 (20 mg/kg/d). Serum levels of xenoantibodies were evaluated by flow cytometry and tissue deposits by immunofluorescence. Immunoblot and indirect immunofluorescence assessed specificity of xenoantibodies. Conventional histology was performed. Continuous administration of UR-12670 improved the histological pattern of liver xenografts, especially necrosis, loss of hepatocytes, hemorrhage, sinusoidal congestion and lymphocyte infiltration. There was not a shift in specificity of xenoantibodies at different times posttransplantation, as demonstrated by immunoblotting and indirect immunofluorescence. UR-12670 administration had a beneficial effect on graft function and considerably improved the histopathological pattern, but it failed to induce tolerance after withdrawal of immunosuppression. UR-12670 had an immunomodulatory effect on cellular response but not on antibody production. There was not a change in the specificity of xenoantibodies produced at LXR compared with pretransplant antibodies. [source] Monitoring of DNA breakage in embryonic stages of the African catfish Clarias gariepinus (Burchell, 1822) after exposure to lead nitrate using alkaline comet assayENVIRONMENTAL TOXICOLOGY, Issue 6 2008Alaa G. M. Osman Abstract Increasing lead contamination in Egyptian ecosystems and high lead concentrations in food items have raised concern for human health and stimulated studies on monitoring ecotoxicological impact of lead-caused genotoxicity. In this work, the alkaline comet assay was modified for monitoring DNA strand breakage in sensitive early life stages of the African catfish Clarias gariepinus. Following exposure to 100, 300, and 500 ,g/L lead nitrate, DNA strand breakage was quantified in embryos at 30, 48, 96, 144, and 168 h post-fertilization (PFS). For quantitative analysis, four commonly used parameters (tail % DNA, %TDNA; head % DNA, %HDNA; tail length, TL; tail moment, TM) were analyzed in 96 nuclei (in triplicates) at each sampling point. The parameter %TDNA revealed highest resolution and lowest variation. A strong correlation between lead concentration, time of exposure, and DNA strand breakage was observed. Here, genotoxicity detected by comet assay preceded the manifested malformations assessed with conventional histology. Qualitative evaluation was carried out using five categories are as follows: undamaged (%TDNA , 10%), low damaged (10% < %TDNA , 25%), median damaged (25 < %TDNA , 50%), highly damaged (50 < %TDNA , 75%), and extremely damaged (%TDNA > 75%) nuclei confirming a dose and time-dependent shift towards increased frequencies of highly and extremely damaged nuclei. A protective capacity provided by a hardened chorion is a an interesting finding in this study as DNA damage in the prehatching stages 30 h-PFS and 48 h-PFS was low in all treatments (qualitative and quantitative analyses). These results clearly show that the comet assay is a sensitive tool for the detection of genotoxicity in vulnerable early life stages of the African catfish and is a method more sensitive than histological parameters for monitoring genotoxic effects. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008. [source] Dissolved copper triggers cell death in the peripheral mechanosensory system of larval fishENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2006Tiffany L. Linbo Abstract Dissolved copper is an increasingly common non,point source contaminant in urban and urbanizing watersheds. In the present study, we investigated the sublethal effects of dissolved copper on the peripheral mechanosensory system, or lateral line, of larval zebrafish (Danio rerio). Zebrafish larvae were exposed to copper (0,65 ,g/L), and the cytotoxic responses of individual lateral line receptor neurons were examined using a combination of in vivo fluorescence imaging, confocal microscopy, scanning electron microscopy, and conventional histology. Dissolved copper triggered a dose-dependent loss of neurons in identified lateral line neuromasts at concentrations ,20 ,g/L. The onset of cell death in the larval mechanosensory system was rapid (<1 h). When copper-exposed zebrafish were transferred to clean water, the lateral line regenerated over the course of 2 d. In contrast, the lateral line of larvae exposed continuously to dissolved copper (50 ,g/L) for 3 d did not recover. Collectively, these results show that peripheral mechanosensory neurons are vulnerable to the neurotoxic effects of copper. Consequently, dissolved copper in non-point source storm-water runoff has the potential to interfere with rheotaxis, schooling, predator avoidance, and other mechanosensory-mediated behaviors that are important for the migration and survival of fish. [source] Hydroxyethyl starch-induced itch: Relevance of light microscopic analysis of semi-thin sections and electron microscopyJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 3 2007Stefanie Kamann Summary Background: Hydroxyethyl starch (HES) is widely used as a plasma substitute for improving microcirculation. A major side effect of HES is severe pruritus caused by HES deposits in the skin. Since specific changes are difficult to see in paraffin sections, electron microscopy is the golden standard technique in the diagnosis of HES-induced skin disease. Our aim was to compare electron microscopic search for HES deposits with other techniques. Patients and Methods: During the last ten years, we biopsied 21 patients suspected of having HES-induced pruritus. We compared conventional microscopy with hematoxylin & eosin and toluidine blue-stained paraffin sections, toluidine blue-stained glycide ether-embedded, semithin sections and transmission electron microscopy. Results: In 9 patients specific HES deposits could be found by evaluating toluidine blue stained semithin sections by light microscopy alone. In 6 of these cases electron microscopy was also done and confirmed the findings. In contrast, no specific findings due to HES deposits could be detected by conventional histology. Conclusions: If specific HES deposits are found in toluidine blue-stained, glycide ether-embedded semithin sections, electron microscopy is not required. [source] A Quantitative Study of the Neural Changes Underlying Pyloric Stenosis in DogsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2002R. M. Abel Summary This study aimed to quantify the neural changes in congenital pyloric stenosis in dogs and to study the comparative anatomy between this condition in dogs and that in infantile hypertrophic pyloric stenosis. Eight specimens from the pylorus of dogs with pyloric stenosis and six control specimens were examined using conventional histology and immunohistochemistry for a range of neural antigens. The changes in the proportion of nerves immunoreactive for each antigen were quantified and analysed statistically. The morphology of the nerves in the diseased dogs was similar to that in controls. Only vasoactive intestinal peptide was reduced in expression in dogs (median proportion in control dogs 0.57, in diseased dogs 0.17; P = 0.065). This study demonstrates both morphological similarities and significant differences between closely related conditions in dogs, humans and other species. [source] ES07 MICROARRAY GENE EXPRESSION ANALYSIS OF HUMAN ADRENOCORTICAL TUMOURSANZ JOURNAL OF SURGERY, Issue 2007P. S. H. Soon Introduction Adrenal tumours are common, occurring in 7% of patients over the age of 50. Adrenocortical carcinomas, however, are rare, with an incidence of two per million population per year. The management of adrenocortical tumours is complex, compounded by the difficulty in discriminating benign from malignant tumours using conventional histology. A molecular marker which could reliably distinguish between the two groups would be valuable in patient management. Objectives The aim of this study was to identify molecular markers which will discriminate between adrenocortical carcinomas and adenomas using microarray gene expression analysis. Methods This study used RNA from 6 normal adrenal cortices, 16 adrenocortical adenomas and 12 carcinomas. Only samples with an RNA integrity number of 7.5 or greater were used. The samples were hybridised to Affymetrix HGU133plus2.0 genechips. Data analysis was performed with Partek and affylmgui softwares. Results Using a cutoff of B > 2 and M > 2 or <,2, 217 genes were found to be significantly differentially expressed between adrenocortical adenomas and carcinomas. Of these genes, 120 were unpregulated while 97 were downregulated. Seven of these genes have been selected for validation studies with real time reverse transcription polymerase chain reaction. Conclusion In this study, we found 217 genes which were significantly differentially expressed between adrenocortical adenomas and carcinomas. With validation and further studies, these genes will provide further insight into the pathogenesis of adrenocortical tumours as well as possibly proving to be reliable discriminators between adrenocortical adenomas and carcinomas. [source] MAGNETIC RESONANCE IN SURGICAL ONCOLOGY: II , LITERATURE REVIEWANZ JOURNAL OF SURGERY, Issue 6 2005Laurence Gluch Ex vivo and in vivo applications of magnetic resonance spectroscopy have been developed which aid in distinguishing malignant from normal tissues. Studies of breast, colon, cervix, oesophageal and prostate cancer reveal both the successes and failings of present technology. Verification that these non-invasive tests might supplant conventional histology in obtaining spatial diagnostic and chemical prognostic information remains for the time being illusive. [source] Pathological tumour diameter predicts risk of conventional subtype in small renal cortical tumoursBJU INTERNATIONAL, Issue 10 2008Melissa A. Laudano OBJECTIVE To examine whether pathological tumour diameter assists in predicting conventional vs other histological subtypes in renal cortical tumours (RCTs) of ,4 cm diameter. PATIENTS AND METHODS In all, 393 patients from Columbia University's Comprehensive Urologic Oncology Database who underwent radical or partial nephrectomy between 1988 and 2005 and had RCTs of ,4 cm were analysed. Logistic regression analysis using tumour diameter as a continuous variable was used to determine whether size predicted histological subtype. Odds ratios (ORs) were calculated to estimate the likelihood of having conventional histology based on diameter. RESULTS The median patient age at surgery was 64.3 years and median tumour diameter was 3 cm, In all, 256 (65.1%) of the RCTs were conventional subtype and 137 (34.9%) were nonconventional. Logistic regression analysis showed that for every 1 cm increase in diameter up to 4 cm, the RCT was 1.27 times more likely to be conventional (P = 0.020). The ORs showed that a 4-cm RCT was 2.06 times more likely to be conventional than tumours of 0.6,1.5 cm. CONCLUSION There was a positive association between RCT diameter and the risk of having conventional renal cell carcinoma (RCC). Given that RCC histological subtype is a prognostic indicator for outcome, these findings may be applied in the selection of treatment options. Further studies investigating tumour size and other variables predictive of tumour histology will help clinicians better predict the RCC subtype. [source] | |||||||||||||