bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host—parasite relationship in the brains of mice with congenital toxoplasmosis
Authors: Sims T. A. , Hay J. , Talbot I. C. 
Published: June 2005

AbstractThe wall of intact tissue cysts in the brains of mice with congenital toxoplasmosis was investigated using light and electron microscopy. Impregnation of the wall with reduced silver salts and protargol silver suggested that it was composed, at least in part, of components derived from the neuronal cytoskeleton. Electron microscopy extended these observations and revealed that intact cysts were separated from the extracellular compartment by a layer of neurofibrillae enclosed within the host cell membrane. It is suggested that this may be a means whereby intact Toxoplasma tissue cysts are protected from the host's immune response.
Epithelial cell markers and proliferating cells in odontogenic jaw cysts
Authors: Matthews John B. , Mason Gillian I. , Browne Roger M. 
Published: June 2005

AbstractThe expression of keratins, CEA, EMA, and rat liver antigen (RLA) and the presence of Ki67+ proliferating cells were studied in the epithelial linings of 50 odontogenic cysts using an indirect immunoperoxidase method on acetone‐fixed frozen sections. All cysts were positive with monoclonal antibodies of broad keratin specificty (CK1, AE1‐3), and between 40 and 100 per cent of epithelial cells expressed keratins 13 and 19. Keratins 7, 8, and 18 were rarely expressed although surface cells in areas of mucous metaplasia often expressed keratins 7 and 18. Expression of keratin 10/11 was related to the presence of a well‐ordered epithelial lining and was detected in isolated cells in 4/32 non‐keratinizing cysts and in the upper suprabasal cell layers of 17/18 keratocysts. Although CEA, EMA, and RLA were detected in the epithelium of all specimens, the pattern of expression of CEA and EMA differed between cyst types. Ki67+ proliferating cells were most prevalent in keratocyst epithelia, where they were usually found within lower suprabasal layers which were negative or weakly positive for keratins 10/11 and 13. These results indicate differences in keratin, CEA, and EMA expression between cyst types which appear to be dependent on epithelial differentiation/structure rather than cyst type or histogenesis. Although these differences may not be of diagnostic significance, the consistent expression of both keratins 13 and 19 may provide a useful marker of odontogenic epithelium in general.
Changes at the glomerulo‐tubular junction in renal transplants
Authors: Lee S. J. , Howie A. J. 
Published: June 2005

AbstractWe studied by microscopy 377 biopsies, nephrectomies, and necropsy kidneys from 123 human renal transplants. We discovered two common abnormalities of the renal corpuscle, both affecting the glomerulo‐tubular junction. Adhesion of the tip of the glomerular tuft to the origin of the tubule, as reported in various non‐transplant glomerulopathies, was seen in 197 specimens (52 per cent). This change was common in material showing acute or chronic vascular rejection and glomerulopathy, and was almost universal in transplants that had been in place for over 1 year. Another change at the glomerulo‐tubular junction, not previously highlighted, consisted of an infiltrate of lymphocytes or neutrophil polymorphs into the epithelium at the tubular origin. This change was seen in 145 specimens (38 per cent) and was associated with cellular rejection and ascending infection. These changes are of importance because they show two responses of the kidney to injury that involve the glomerulo‐tubular junction and thus suggest that this part of the kidney has some specific properties that have been largely neglected up to now.
Oncogenes and onco‐suppressor genes: Their involvement in cancer
Authors: Spandidos Demetrios A. , Anderson Margaret L. M. 
Published: June 2005

AbstractWe review the involvement of two groups of genes, oncogenes and onco‐suppressor genes, in malignant transformation. Approximately 40 oncogenes have been described mainly through studies on retroviruses and by in vitro functional analyses such as transfection of transforming genes into ‘normal’ cells. Because they are more difficult to identify, only a handful of onco‐suppressor genes have been described so far, but potentially they could number as many as oncogenes. Where these genes have been isolated and sequenced, they have been shown to be highly conserved among species, suggesting that these genes play an essential role in the normal cell. Although some properties of oncogenes have been identified, we do not know in detail the role these genes play in normal cells or how genetic damage contributes to malignancy. The effect of oncogene expression on a cell depends both on the cell type and on the oncogene, and in some circumstances oncogenes act as onco‐suppressor genes and vice versa. The elucidation of the mechanism of action of oncogenes and onco‐suppressor genes will not only increase our understanding of these important genes but might also provide the framework for a biological approach to the treatment of cancer.
Mast cells in human lungs
Authors: Heard Brian E. , Nunn Andrew J. , Kay A. B. 
Published: June 2005

AbstractMast cells were stained deeply in human lung tissue with acidic toluidine blue to obtain maximum numbers possible in paraffin sections. One hundred high‐power fields were counted per section, and mean and median values summarized as mast cells per mm2.Immersion‐fixed samples of fresh lung tissue (not bronchi) were taken as controls from seven patients after surgery, and showed mean values of 44.7 mast cells per mm2 after formalin fixation, and 51.9 per mm2 after Carnoy's fixative. Mast cell heterogeneity may explain these differences, but so could random variation between counts.In two patients with extrinsic allergic alveolitis (hypersensitivity pneumonitis), fresh lung tissue from open lung biopsies showed raised values of 90.8 and 101.9 mast cells per mm2, matching the high mast cell counts reported in bronchopulmonary lavage fluid in the condition.Control post‐mortem lung tissue from two patients dying of non‐pulmonary diseases showed mean values of 26.1 and 50.6 mast cells per mm2. Post‐mortem lung tissue from three patients dying of asthma showed very low mean values of 4.7, 5.7, and 5.9 mast cells per mm2. Low mast cell counts due to severe degranulation have been reported before in the bronchi in asthma deaths, but not, to our knowledge, in the lung parenchyma. This finding implies a wider area of mediator release, and helps to explain the severity of the acute attack, and the fatal outcome.
Macroscopic and microscopic early effects of tumour necrosis factor on murine Meth A sarcoma, and relation to curative activity
Authors: van de Wiel Paul A. , Bloksma Nanne , Kuper C. Frieke , Hofhuis Frans M. , Willers Jan. M. 
Published: June 2005

AbstractMice with solid Meth A sarcoma in the skin received an intravenous or intralesional injection of graded doses of recombinant human tumour necrosis factor (rTNF). Local treatment caused red discolouration and necrosis of the central portion of the tumour within 24 h over a larger range of doses than intravenous treatment. Effects showed a limited dose dependence and no significant correlation with subsequent cures, which were far more frequent after local treatment. A dose of rTNF that induced about equal macroscopic necrosis by both routes caused much more pronounced microscopic effects after local administration. Effects included mitotic arrest, granulocyte margination, endothelial damage, hyperaemia, congestion, oedema, and tumour cell necrosis. rTNF did not affect the Meth A cells in vitro. Locally injected skins showed moderate vascular effects which were more marked in tumour‐bearing mice, but skin necrosis was absent.Data show that quantitative histology rather than macroscopically visible necrosis correlates with cure rates. A broad interference of rTNF with tumour blood supply seems to be a major cause of the induced necrosis. Granulocytes may be involved in vascular damage. The different effects of rTNF on skin and tumour indicate that tumour vasculature has enhanced susceptibility to rTNF and probably lesser repair capacity.
Different types of segmental sclerosing glomerular lesions in six experimental models of proteinuria
Authors: Howie A. J. , Kizaki T. , Beaman M. , Morland C. M. , Birtwistle R. J. , Adu D. , Michael J. , Williams A. J. , Walls J. , Matsuyama M. , Shimizu F. 
Published: June 2005

AbstractFrom 133 to 615 glomeruli were examined in sections of kidneys from each of 60 animals, representing six rodent models of proteinuria. Particular attention was paid to the position of segmental lesions. Lewis rats given sheep anti‐rat glomerular basement membrane antibodies had lesions almost exclusively at the glomerulo‐tubular junction. Wistar rats on a diet of 24 per cent casein or with subtotal nephrectomy and a diet of 24 per cent soya had lesions mainly at the hilum. Wistar rats given bovine serum albumin had global lesions but virtually no segmental lesions. Wistar rats given puromycin aminonucleoside had lesions at the glomerulo‐tubular junction and global mesangial abnormalities shortly after the treatment but later developed segmental lesions at all parts of the glomerulus. Untreated BUF/Mna rats had lesions at the glomerulo‐tubular junction early in life but later had lesions at all parts of the glomerulus. Untreated NZB/NZW hybrid mice had various types of glomerulonephritis and also had lesions at the glomerulo‐tubular junction. These findings showed that (1) segmental lesions at the glomerulo‐tubular junction, or glomerular tip, occur in experimental animals, a fact not previously reported, and these tip changes are a common feature in several different models of proteinuria; (2) hilar segmental lesions are seen in conditions with hyperfiltration of protein; and (3) segmental lesions at various parts of the glomerulus are seen in some models of proteinuria and probably indicate late effects of random toxic damage to the glomerulus. Thus, there are at least three different types of segmental glomerular lesions in experimental animals—tip, hilar, and random—with different morphology and pathogenesis. It is likely that these findings can be extended to human renal diseases with segmental glomerular lesions. This will help to clarify the controversial and unsatisfactory term focal segmental glomerulosclerosis.
Expression of the nuclear oncogene p53 in colon tumours
Authors: Van Den Berg F. M. , Tigges A. J. , Schipper M. E. I. , Den Hartog‐Jager F. C. A. , Kroes W. G. M. , Walboomers J. M. M. 
Published: June 2005

AbstractThe nuclear tumour antigen p53 is expressed by a gene localized on the p‐arm of human chromosome 17, a region frequently deleted in colon carcinomas. Using a monoclonal antibody to p53 antigen, immunohistochemical analysis of carcinomas and dysplastic tubular adenomas of the colon has been performed to study the relation between p53 expression and dysplasia or malignancy. With this methods p53 was detectable in 55 per cent of colon carcinomas (n = 29).In 8 per cent of adenomas (n = 74), focal nuclear p53 expression was found in dysplastic epithelial cells. In general, these p53‐positive regions of the polyps were histologically indistinguishable from the neighbouring tubuli. Sometimes the p53‐positive nuclei were found in a focus of more highly dysplastic epithelium. The results suggest that expression of the p53 gene may be part of the process of malignant transformation of dysplastic colon polyps.
Immunohistological determination of oestrogen receptor, progesterone receptor, and intermediate filaments in Leydig cell tumours, Leydig cell hyperplasia, and normal Leydig cells of the human testis
Authors: Düe Wolfgang , Dieckmann Klaus‐Peter , Loy Volker , Stein Harald 
Published: June 2005

AbstractTesticular Leydig cell tumours are able to produce oestrogens and can be induced by exogeneous oestrogen administration. Oestrogen and progestrone receptors, cytokeratin, vimentin, and proliferative activity were determined immunohistologically in human testes in six Leydig cell tumours, 14cases of Leydig cell hyperplasia, and 13 cases with normal Leydig cells. While both steroid receptors were detected in about 70 per cent of the tumour cells in cryostat sections, no reaction was observed in normal Leydig cells. This supports the hypothesis of an enhanced receptor state in a Leydig cell subpopulation as a basic pathophysiological factor in the development of Leydig cell tumours. On cryostat sections, all tumours co‐express cytokeratin and vimentin. Neither the receptors nor the intermediate filaments could be detected reliably in paraffin sections. The low proliferative activity of Leydig cell tumours corresponds to their benign clinical course.
Vascular volume in B16 allografts and human melanoma xenografts estimated by means of Hoechst 33342
Authors: Fallowfield Mary E. 
Published: June 2005

AbstractThe vasculature of B16, a murine melanoma and Mel‐mo, a human melanoma, was studied using intravital staining of patent capillaries by the fluorescent bisbenzamine dy Hoechst 33342. Capillaries were numerous at the edge of tumours in both the lines studied, but were scarcer within the nodules. Vascular volume as a proportion of total tumour volume was estimated by means of point counting. In both B16 and Mel‐mo, the percentage vascular volume was inversely related to log tumour weight.Tumour necrosis, which increased with tumour size, was inversely correlated with percentage vascular volume, emphasizing the central under‐perfusion of these experimental tumour nodules. This pattern of perfusion, with greater density of functioning capillaries at the periphery of tumour nodules, was seen in both the tumour lines examined despite differences in the degree and pattern of necrosis.
Detection of latent virus mRNA in tissues using the polymerase chain reaction
Authors: Lynas Caroline , Cook Stuart D. , Laycock Keith A. , Bradfield John W. B. , Maitland Norman J. 
Published: June 2005

AbstractThe polymerase chain reaction (PCR) has been adapted for use in gene expression studies. Using this technique, we have been able to specifically detect Herpes simplex virus gene expression in the amount of RNA equivalent to that present in a single mouse ganglion. We have also detected specific transcription of the ras oncogene in biopsies of hepatocellular carcinoma tissue. The single tube RNA PCR reaction should be readily adaptable for use as a rapid screening tool in virus diagnosis; it is capable of detecting several virus infections simultaneously using extremely small tissue biopsies.
Silver‐binding nucleolar organizer regions (AgNORs) in benign and malignant breast lesions: Correlations with ploidy and growth phase by DNA flow cytometry
Authors: Giri D. D. , Nottingham J. F. , Lawry J. , Dundas S. A. C. , Underwood J. C. E. 
Published: June 2005

AbstractSilver‐binding nucleolar organizer regions (AgNORs) have been counted in sections of routinely processed paraffin‐embedded tissue blocks and have been shown to assist in the distinction between benign and malignant lesions. We have examined 214 benign and malignant breast lesions by this method. The AgNOR counts were fibroadenomas 1.87 + 0.20 (mean + SD; n = 39), papillomas 1.92 + 0.21 (n = 28), sclerosing adenosis 1.96 + 0.24 (n = 23), epitheliosis 2.21 + 0.30 (n = 38), lobular carcinoma in situ 2.67 + 0.54 (n =9), intraduct carcinoma 3.75 + 1.33 (n = 37), and invasive carcinoma 4.22 + 1.18 (n = 40). However, the counts in 25–30 per cent of epitheliosis lesions and intraduct carcinomas overlapped in the region of 2–3 AgNOR dots per nuclear profile. The AgNOR counts in carcinomas were also compared with ploidy and growth phase fractions (S + G2 + M%) by flow cytometry. Thirty‐three of the 46 cancers with counts over 3 AgNOR dots per nuclear profile contained aneuploid cells (> 10 per cent of the total), whereas 8 of the 12 with counts below 3 comprised diploid cells only (P <0.05). Similar trends were noted with regard to growth phase fractions which were 19.15 per cent + 12.31 and 13.98 per cent + 5.55, respectively, for the two groups (P>0.10). We conclude that this method alone does not offer a reliable histological discriminant for malignancy in the breast. However, AgNOR counting may provide information on breast cancer prognosis supplementary to that obtained from DNA flow cytometric analyses.
IgA nephropathy associated with chronic hepatitis B virus infection in adults: The pathogenetic role of HBsAG
Authors: Lai Kar Neng , Lai Fernand Mac‐Moune , Tam John S. 
Published: June 2005

AbstractFive adult cases of IgA nephropathy associated with chronic hepatitis B virus infection were studied. Serum HBsAg and anti‐HBc were present in five patients and HBeAg in four patients. Glomerular changes were typical of primary IgA nephropathy in four patients, and a mixed picture of IgA and membranous nephropathy was demonstrated in one patient. Immunofluorescence microscopy using polyclonal and monoclonal antibodies against HBsAg, HBcAg, and HBcAg revealed mesangial deposits of HBsAg in renal biopsies from four patients. One renal biopsy showed only mesangial and capillary HBcAg by polyclonal antiserum, and virus‐like particles were demonstrated in the intramembranous electron‐dense deposits on ultrastructural examination. Mesangial HBeAg was not detected in the renal biopsies from these patients with IgA nephropathy. As for the single patient with a mixed picture of IgA and membranous nephropathy, granular deposits of HBeAg with a distribution similar to IgG were detected in the glomerular capillary walls in addition to the mesangial deposition of HBsAg. These findings suggest that HBsAg rather than HBeAg may play a role of the pathogenesis in some of the adult patients with IgA nephropathy associated with chronic hepatitis B virus infection.
Primary liver neoplasms: Evaluation of proliferative index using MoAb Ki 67
Authors: Grigioni W. F. , D'Errico A. , Bacci F. , Gaudio M. , Mazziotti A. , Gozzetti G. , Mancini A. M. 
Published: June 2005

AbstractThirty‐two cases of primary liver neoplasms comprising 12 benign, 15 malignant, and 5 cases with equivocal histopathological features between benign and malignant have been investigated using monoclonal antibody (MoAb) Ki 67, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle.The Ki67 score (positive cells/total neoplastic cells) seems to correlate to the classes of lesions tested. In the hepatocellular carcinoma (HCC) group, the percentage of labelled nuclei, ranging from 15 to 50 per cent, showed a good correlation with Edmondson‐Steiner's histological tumour grade.A percentage of positive cells similar to that of the proved low‐grade HCCs was detected in the five neoplastic lesions in which the routine histopathological criteria of malignancy were not fulfilled. The benign neoplasms showed a very low growth fraction, similar to that of normal or cirrhotic tissues.The use of the Ki 67 score seems to offer useful information about the biological behaviour of some liver masses and may help in the differential diagnosis of hepatocellular adenoma versus carcinoma.
Pleural mesothelioma of connective tissue type, localized fibrous tumour of the pleura, and reactive submesothelial hyperplasia. An immunohistochemical comparison
Authors: Al‐Izzi Moutaiz , Thurlow Nicola P. , Corrin Bryan 
Published: June 2005

AbstractTen diffuse pleural mesotheliomas of connective tissue type have been compared with 14 examples of pleural granulation tissue and 7 localized fibrous tumours of the pleura, using immunohistochemistry to identify cytokeralins oflow and high molecular weight and vimentin. Low molecular weight cytokeratin and vimentin were both delected in 8 of the 10 mesotheliomas and in 12 of the 14 reactive iesions. High molecular weight cylokeratin was rarely detected in either lesion. The seven localized fibrous tumours of the pleura were all positive for virnentin and negative for both cytokeratins. These findings support an origin of connective tissue type mesotheliomas from multipotential submesothelial spindle cells and of localized fibrous tumours of the pleura from either conventional fibroblasts or resting submesothelial spindle cells. Antibodies to cytokeratin help distinguish these two neoplasms but provide no assistance in the more difficult diagnostic problem of distinguishing mesotheliomas of connective tissue type from pleural reactions characterized by abundant granulation tissue.
In situ evaluation of the stimulatory state of hepatic macrophages based on their ability to produce superoxide anions in rats
Authors: Mochida Satoshi , Ogata Itsuro , Ohta Yasuhiko , Yamada Shinwa , Fujiwara Kenji 
Published: June 2005

AbstractWhen a liver perfusion with nitro blue tetrazolium (NBT) and phorbol myristate acetate (PMA) was performed in carbon tetrachloridc (CCl4)‐intoxicated rats, formazan deposition was remarkable in macrophages in the necrotic areas of the liver, its intensity varying with the extent of injury. The deposits almost disappeared after addition of Cu(Lys)2 a scavenger of intra‐ and extracellular superoxide, but were not affected by superoxide dismutase (SOD), which acts extracellularly. The formazan content after incubation with NBT and PMA was higher in macrophages isolated from CCl4‐intoxicated liver than in those from normal liver, though their PMA‐induced chemiluminescence did not differ. In Corynebacteriun parvum‐treated liver, both Cu(Lys)2 and SOD reduced the deposits. This method cn estimate in situ the ability of hepatic macrophages to produce superoxide and the cellular sites of its production.
An immunohistochemical and in situ hybridization study of c‐myc and c‐erbB‐2 expression in primary human breast carcinomas
Authors: Walker Rosemary A. , Senior P. V. , Jones J. Louise , Critchley D. R. , Varley Jennifer M. 
Published: June 2005

AbstractIn previous studies of the expression and organization of proto‐oncogenes in human breast a significant correlation has been found between amplification of c‐myc and c‐erbB‐2 genes in carcinomas and poor short‐term prognosis. Gene expression was estimated by analysis of total RNA from tissues, and similarly assessment of gene organization relied upon extraction of DNA from tissues. The present study has compared the expression of c‐myc and c‐erbB‐2 mRNA as determined by in situ hybridization, and c‐myc and c‐erbB‐2 protein expression detected by immunohistochemistry in a group of carcinomas for which there was knowledge of genomic organization and/or expression.Formalin‐fixed, paraffin‐embedded tissues of 38 carcinomas were assessed for the presence of c‐myc protein, and 13 of these were examined for c‐myc mRNA by in situ hybridization. Similarly processed tissue from 14 tumours was tested for c‐erbB‐2 protein using the antiserum21N and ten of these carcinomas studied for c‐erbB‐2 mRN A localization.There was a good correlation between gene amplification, the presence of c‐erbB‐2 protein and mRNA: both the latter were detected in six of the seven carcinomas with an amplification but in none without. For some carcinomas there was a good correlation between c‐myc protein and mRNA levels. Three carcinomas with gene amplification had a lower percentage of cells with detectable protein than showed hybridization for mRNA. Other carcinomas had a lower level of mRNA expression than protein. Neither approach could predict which carcinomas had amplification of the c‐myc gene. The subcellular localization of the c‐myc protein was affected by fixation.Localization of c‐erbB‐2 protein and mRNA in routinely processed tissues could provide information of clinical value but the same cannot be said for expression of c‐myc.