bluuebunny/crossref_metadata_2025 huggingface dataset:
Basement membrane laminin‐5 is deposited in colorectal adenomas and carcinomas and serves as a ligand for α3β1 integrin
Authors: Lohi Jouni , Oivula Jan , Kivilaakso Eero , Kiviluoto Tuula , FrÖjdman Kim , Yamada YOshihiko , Burgeson Robert E. , Leivo Ilmo , Virtanen Ismo
Published: October 2003

Interplay between laminin‐5 (Ln‐5) and its integrin (Int) receptors α2β1, α3β1 and α6β4 has been implicated in the progression and invasion of carcinomas. In this study we found abundant immuno‐reactivity for chains of Ln‐5 (α3‐β3‐γ2) and Ln‐10 (α5‐β1), as well as for type VII collagen, in basement membranes (BM) of colorectal adenomas. In carcinomas of all differentiation grades, Lns were seen in tumor BMs, whereas type VII collagen was almost absent. Ln‐5 appeared to accumulate along the invading edges of carcinomas, while Ln‐10 was mostly absent. Immunoreactivity for Ln α1 chain, a component of Lns‐1 and ‐3, was not seen in adenomas or carcinomas. Immunoreactivity for α2, α6, β1 and β4 Ints was found in all tumors and that for α3 Int in all adenomas and most of the carcinomas, often in colocalization with Ln‐5. Immunoblotting of carcinoma tissues showed that the γ2 chain of Ln‐5 was present as typical Mr 105000 and 155000 isoforms. Immunoprecipitation experiments showed production of Ln‐5 by cultured colon carcinoma cells. In quantitative cell adhesion experiments, function‐blocking MAbs to α3 and β1 Int subunits, but not those to Int α2 or α6 subunits, significantly inhibited the adhesion of cells to Ln‐5. Our results suggest that BM composition in colorectal adenomas reflects the properties of surface epithelial BM of colorectal mucosa. In invading carcinomas, trimeric Ln‐5, produced by carcinoma cells, is a major BM component and the cells use the α3β1 Int complex for adhesion to Ln‐5.
Well‐differentiated adenocarcinoma of the gallbladder mimicking minimal deviation adenocarcinoma of the cervix.
Authors: Tashiro Takashi , Hirokawa Mitsuyoshi , Horiguchi Hidehisa , Wakatsuki Shingo , Sano Toshiaki , Yada SEigo
Published: October 2003

We report a case of well‐differentiated adenocarcinoma of the gallbladder, histologically mimicking minimal deviation adenocarcinoma (MDA) of the cervix. A 71‐year‐old Japanese male underwent cholecystectomy because of the suggestion of gallbladder carcinoma. The resected gallbladder showed a localized thickening of the gallbladder wall with a polypoid lesion measuring 12 × 7 mm in diameter. Microscopically, the polypoid lesion proved to be a well‐differentiated adenocarcinoma composed of columnar cells with a clear cytoplasm. In the thickened gallbladder wall, well‐formed glands were extensively distributed; they were surrounded by a slightly desmoplastic reaction instead of lamina propria, or were directly in contact with smooth muscle cells. The diagnostic criteria for cervical MDA may be useful in distinguishing well‐differentiated adenocarcinoma of the gallbladder from benign conditions, such as Rokitansky‐Aschoff sinus and adenomyomatosis. It is remarkable that the tumor cells of the present case expressed gastric type mucin which is characteristic of mucinous type cervical MDA.
Mucosal and systemic antibody responses after peroral or intranasal immunization: Effects of conjugation to enterotoxin B subunits and/or of co‐administration with free toxin as adjuvant
Authors: Rask C. , Fredriksson M. , Lindblad M. , Czerkinsky C. , Holmgren J.
Published: October 2003

The mucosa‐binding molecules cholera toxin (CT) from Vibrio cholerae and heat‐labile enterotoxin (LT) from Escherichia coli have previously been used as mucosal adjuvants and carriers for many types of antigen. However, since these molecules are toxic and cannot be used in human vaccines, it is important to study whether their non‐toxic mucosa‐binding B subunits, CTB and LTB, can be used as alternative safe mucosal adjuvants and/or carrier molecules. We have as a model protein antigen used human gammaglobulin (HGG) for admixture with or chemical conjugation to recombinantly produced CTB and LTB, respectively, and measured antigen‐specific local secretory IgA antibodies in saponin extracts from intestine and lung tissue by ELISA following intra‐nasal (i.n.) or per‐oral (p.o.) immunization. The results show that local antibody formation against HGG was increased after immunization with conjugated as compared to free HGG. However, while the conjugates alone gave rise to significant immune responses in the lung and also, to a lesser degree, in the intestine after i.n. immunization, co‐administration of a small amount of free CT/LT as adjuvant was needed to induce a significant immune response in the intestine after p.o. immunization. We also found that following i.n. immunization, the addition of CTB to HGG, without coupling, increased the mucosal immune response to some extent, indicating that CTB by itself can work as an adjuvant by the i.n. route of immunization. A striking finding was that, as a carrier, CTB was superior to LTB when the conjugates were used by the oral but not by the i.n. route of immunization. In conclusion, conjugation of an antigen to mucosa‐binding molecules such as CTB and/or LTB can dramatically increase their mucosal immunogenicity. This approach may thus be useful in the preparation of mucosal vaccines.
Histopathological and morphometric analyses of late rectal injury after irradiation
Authors: Lundby Lilli , Overgaard Jens , Laurberg Søren
Published: October 2003

The aim of the present study was to assess and quantify changes in the structural components of the rectal wall after irradiation with varying single doses of x‐rays. A total of 70 CDF1/Bom male mice were irradiated at a selective 1.5 cm of the distal rectum with varying single doses of 0–30 Gy. At 32 weeks postirradiation the mice were sacrificed and the rectum was removed. Sampling of the specimens was based on unbiased stereological principles using systematic random sampling. Vertical tissue sections were used to estimate mucosal surface area density and to measure the thickness and volume fraction of the different intestinal wall layers. The surface area density decreased with increasing dose (p<0.02) due to pronounced injury of the crypts and mucosal morphology. The thickness and the volume fraction of the submucosa were significantly increased in the 20, 25 and 30 Gy treatment groups (p<0.0001 and p<0.0001), whereas the thicknesses of the mucosa, the lamina muscularis propria and the serosa did not change after irradiation. It is concluded that irradiation causes histopathological changes in the rectal mucosa and submucosa, and changes in the thickness of the submucosal intestinal layer. These changes were found to be dose‐dependent.
Application of four molecular techniques for typing outbreak‐associated Mycobacterium tuberculosis strains
Authors: Rodriguez J. C. , Royo G. , Rodriguez‐Valera F.
Published: October 2003

We applied four molecular techniques for the typing of strains of Mycobacterium tuberculosis associated with outbreaks: RFLP of the IS6110 insertion sequence, spoligotyping, RAPD, and PCR‐IS6110. All 4 techniques were applied to 18 strains which were shown by epidemiological data to be involved in 6 outbreaks. All the methods classified the strains into the same groups as the classical epidemiological data did, but RFLP of the IS6110 insertion sequence and spoligotyping are laborious techniques requiring more than a full day's work, whilst RAPD and PCR IS6110 are simple methods easily incorporated into the daily routine. Nevertheless, a large‐scale process of standardization and evaluation is necessary in order to be able to establish the true value of the latter two methods as intraspecific characterization markers for M. tuberculosis isolates.
Evaluation of post‐antibiotic effects of antipseudomonal antibiotics using an automated system
Authors: Mayer I. , Nagy E.
Published: October 2003

Different methods have been described for determination of the post‐antibiotic effects (PAEs) of antibiotics, from the conventional methods to the automatic measurement of bacterial regrowth. The PAEs of ciprofloxacin, ofloxacin and pefloxacin, as compared with those of amikacin, netilmicin and ceftazidime, have now been investigated for three clinical isolates of Pseudomonas species, using automated measurement of the growth with an Anthos microplate reader. It was found that, besides the well‐known PAEs of aminoglycosides, quinolone antibiotics also exhibit drug‐ and concentration‐dependent PAEs against clinical isolates of Pseudomonas when used in concentrations of 1/2x, 1x or 5x MIC. Of the three quinolones tested, pefloxacin showed the greatest PAE, independently of its MICs against the different strains. Ofloxacin had no or only an insignificant PAE, while ciprofloxacin had a marked PAE for all strains, including the reference strains.
The effects of live Neisseria meningitidis and tumour necrosis factor‐α on neutrophil oxidative burst and β2‐integrin expression
Authors: Kragsbjerg P. , Fogelqvist M. , Fredlund H.
Published: October 2003

The effects of human recombinant tumour necrosis factor‐α (TNF‐α) on neutrophil (PMNL) oxidative burst and on CD11b/CD18 and CD14 expression after stimulation with pathogenic or nonpathogenic Neisseria meningitidis were studied using chemiluminescence and flow cytometry. PMNL oxidative burst increased more when stimulated with the apathogenic 29E strain than with the pathogenic B strain both when studied by chemiluminescence and by flow cytometry. When TNF‐α was added to whole blood or PMNL together with bacteria a significant increase in the oxidative burst was seen for the B strain only. When whole blood was preincubated for 30 min with TNF‐α the increase in oxidative burst was significant for both meningococcal strains. TNF‐α caused a significant increase in PMNL CD11b/CD18 expression after 30 min of incubation at 37°C. TNF‐α added simultaneously with the bacteria induced a significant increase in PMNL CD11b/CD18 in both strains. Incubation with the B strain alone caused a low but significant increase in CD11b/CD18 expression, but the addition of TNF‐α increased this expression to the same high level as incubation with TNF‐α alone or the 29E strain alone. Only TNF‐α and the 29E strain caused significant increases in CD14 expression. In conclusion, human PMNLs react differentially when stimulated with pathogenic and nonpathogenic N. meningitidis and the activating effect of TNF‐α is variable depending on the bacteria involved.
Intravenous tufted angioma
Authors: Fukunaga Masaharu
Published: October 2003

A case of a rare vascular tumor, intravenous tufted angioma, is described. A 51‐year‐old Japanese man presented with a 12x8 mm solitary reddish nodule on the right foot, which had been found at birth. Histologically, the tumor was confined to a malformed vein and was characterized by nodular aggregates of plump cells. The aggregates showed a compact proliferation of round cells, including capillary‐forming cells. Venous angiomatous areas were also observed. No multinucleated giant cells were seen. Immunohistochemically, the capillary‐forming cells in the aggregates and the endothelial cells in the angiomatous areas were positive for endothelial markers (factor VIII‐related antigen, CD31, CD34). Pericyte‐like cells expressing α‐smooth muscle actin and muscle actin, and macrophage‐like cells, which stained for factor XIIIa, were intermingled in the cellular aggregates. Flow cytometric analysis showed diploidy. The tumor may be a hamartomatous lesion modified by secondary reactive changes, and it may represent a distinctive clinicopathological entity that is closely related histogenetically and perhaps pathologically to tufted angioma and the recently described “giant cell angioblastoma”.
Emm gene polymorphism among temporally clustered group A streptococcal isolates in western Norway
Authors: Mylvaganam H. , Bjorvatn B. , Hofstad T. , Osland A.
Published: October 2003

Nineteen group A streptococcal isolates obtained in western Norway from patients with invasive disease during a period of high morbidity and mortality were examined for clonality and emm gene polymorphism. These isolates belonged to the prevalent serotypes during the outbreak, namely T1, T3 or T6. Restriction fragment length polymorphism and sequencing of the emm genes were used to compare these isolates with 14 isolates of the same serotype but from non‐invasive infections. The restriction analysis did not identify specific invasive clones. The emm genes in three of the four T3 isolates from invasive disease had nucleotide substitutions inducing a charge difference in the N‐terminal part of the M protein. The 4 T6 isolates had a longer emm amplicon when compared to 15 isolates from superficial infections and also showed nucleotide substitutions that could induce conformational changes in the hypervariable end of the M protein. Restriction analysis of the emm amplicon of the T6 isolates in order to estimate the number of A‐ and C‐repeats is described. The emm gene sequence served as an epidemiological marker within the serotypes T3 and T6, but the significance of the emm polymorphism displayed by the isolates from invasive disease is uncertain at this stage.
Overexpression of human lecithin:cholesterol acyltransferase in mice offers no protection against diet‐induced atherosclerosisNote
Authors: MEHLUM ANJA , GJERNES ELISABETH , SOLBERG LARS AAGE , HAGVE TOR ARNE , PRYDZ HANS
Published: October 2003

Human lecithin:cholesterol acyltransferase (LCAT) is a key enzyme in the metabolism of cholesterol. We have used homozygous transgenic mice overexpressing the human LCAT transgene to study the effect of a “Western‐type” atherogenic diet (30% fat, 5% cholesterol and 2% cholic acid) on their LCAT expression, activity, lipoprotein profile and tendency to develop atherosclerosis. The LCAT activity was 35‐fold higher in serum of the homozygous transgenic mice than in murine control serum, and decreased 11–20% in the transgenic mice when fed the atherogenic diet. The total cholesterol and high‐density lipoprotein cholesterol (HDL‐C) concentrations were approximately doubled in the transgenic mice compared with the controls when both groups were fed a regular chow diet. In mice on the atherogenic diet, the triglyceride concentration decreased about 50% to the same level in transgenic and control mice. Total cholesterol and HDL‐C concentrations increased and were 60–80% higher in the transgenic mice. The expression of LCAT mRNA in the liver was decreased by 49–60% in the transgenic mice when fed the atherogenic diet. The development of atherosclerosis was similar in transgenic and control mice. Thus, the 14‐ to 27‐fold higher LCAT activity and the higher HDL‐C concentrations in the homozygous LCAT transgenic mice had no significant protective influence on the development of diet‐induced atherosclerosis.
A new model for evaluation of thrombosis and ischaemia/reperfusion injury
Authors: Ravn Hanne B. , MøLdrup Ulla , Ilkjær Lars B. , Chew Michelle , Jensen Liselotte , Johnsen SøRen , Birk‐SøRensen Lene , TøNnesen Else , Hjortdal VIbeke E.
Published: October 2003

Background: The purpose of the present study was to describe infarct size and platelet accumulation when reperfusion injury was combined with a thrombogenic lesion in the coronary artery. The left anterior descending artery was damaged in 11 pigs and subsequently occluded proximal to the lesion for 50 min, followed by 4 h of reperfusion.Results: The infarct size/area at risk was 40 (35–63)%. Infarct size correlated with troponin‐T‐3 h (p=0.85, p<0.002), but not with creatine kinase‐3 h. Platelet aggregation decreased by 34% (p<0.01) at 15 min of reperfusion, but returned to baseline. Platelet accumulation in the left ventricle was significantly higher in the area at risk (194 (157–206)%) compared to the right ventricle (137 (120–142)%); p<0.05).Conclusion: A decreased platelet reactivity and increased accumulation of platelets in the area at risk indicates that activated platelets become entrapped in the myocardium. Troponin‐T was a better marker of myocardial damage than creatine kinase in this in vivo model with pigs.
Argyrophilic nucleolar organizer regions in Helicobacter pylori‐associated gastric lesions
Authors: Misra Vatsala , Bisht Dipti , Misra Sri Prakash , Dwivedi Manisha , Bhatia Ritu
Published: October 2003

Three hundred and fifty biopsies from patients undergoing upper gastrointestinal endoscopy were studied for histopathological changes, H. pylori infection and argyrophilic nucleolar organizer region (AgNOR) counts. Histopathological examination revealed normal gastric mucosa in 10 (2.85%), gastritis in 254 (72.56%), intestinal metaplasia in 12 (4.0%), dysplasia in 13 (3.7%) and adenocarcinoma in 61 (17.4%). The mean (SD) AgNOR count was 1.66 (0.20) in normal, 2.43 (0.64) in gastritis, 3.09 (0.52) in intestinal metaplasia, 4.17 (0.31) in dysplasia, and 6.57 (0.98) in carcinoma. A statistically significant difference was observed between the AgNOR count of normal gastric mucosa and gastritis (p<0.001), gastritis and dysplasia (p<0.001), and dysplasia and adenocarcinoma (p<0.001). A statistically significant increase in mean AgNOR count was found with increase in H. pylori density in gastric biopsies (p<0.001) with gastritis. No significant difference was observed between mean AgNOR count of intestinal and diffuse type carcinomas. The AgNOR count in gastric biopsies with adenocarcinoma and H. pylori infection was 7.03 (0.85) as compared to 6.89 (0.73) in gastric biopsies with evidence of adenocarcinoma but without H. pylori infection. The difference was not statistically significant. The findings support the role of H. pylori as a promoting agent in gastric carcinogenesis by stimulating gastric epithelial cell proliferation at the stage of chronic inflammation, thereby making the cells more susceptible to endogenous or exogenous carcinogenic agents.
Human T‐lymphocyte virus type I (HTLV‐I)‐induced myeloneuropathy in rats: Oligodendrocytes undergo apoptosis in the presence of HTLV‐I
Authors: Ohya Osamu , Ikeda Hitoshi , Tomaru Utano , Yamashita Isao , Kasai Takefumi , Morita Keisuke , Wakisaka Akemi , Yoshiki Takashi
Published: October 2003

To investigate the pathogenetic role of human T‐lymphocyte virus type I (HTLV‐I) in central nervous system disease, a rat model for HTLV‐I‐associated myelopathy/tropical spastic paraparesis, designated as HAM rat disease, was examined with regard to chronological neuropathology, from early asymptomatic phase to late disease. In the thoracic spinal cord of rats with HTLV‐I infection, the first event was the appearance of apoptosis of oligodendrocytes beginning at 7 months after induced infection, thereafter followed by the appearance of white matter degeneration, increase of macrophages/activated microglia and of gemistocytic astrocytes at 12, 15 and 20 months, respectively. In the spinal cord, HTLV‐I provirus DNA was evident as early as 4 months after the infection, and HTLV‐I pX and the tumor necrosis factor (TNF)‐α messages began to be expressed at age 7 months, just before or at the same time as the appearance of apoptotic cells. Collective evidence suggests that the apoptotic death of oligodendrocytes, which may be induced either directly by the local expression of HTLV‐I or indirectly by TNF‐α, through the transactive function of p40Tax, is the major cause of chronic progressive myeloneuropathy in Wistar‐King‐Aptekman‐Hokudai rats with HTLV‐I infection.
Regulation of IgE‐receptor expression, IgE occupancy and secretory capacity of mast cells
Authors: Chen XIAO‐JUN , EnerbÄCk LENNART
Published: October 2003

Mast cells play an important role in initiating and modulating allergic and inflammatory reactions. Their responsiveness is determined by three important factors: the expression of IgE receptors on the cell surface, the IgE occupancy of these receptors, and the intrinsic secretory capacity of the cells. In this review, we will summarise some findings relevant to these three aspects of mast cell function, and discuss possible regulatory mechanisms. It appears that the genetic background as well as environmental factors influence all three of these components of the response. T cells appear to play an important role in regulating the IgE‐receptor expression and also, independently, the intrinsic secretory capacity of mast cells via an unidentified route, possibly involving the secretory signal transduction chain directly. IgE itself appears to have an important role in the regulation of IgE‐receptor expression, as indicated by the upregulation of receptors in vitro in the presence of IgE, and the absence of IgE‐binding capacity of mast cells in IL‐4 gene knockout mice, lacking IgE production. The IgE‐receptors of mast cells are saturated to a high degree under different normal conditions, without an obvious relation to antigenic stimulation, also in athymic animals. We have suggested that this basal IgE content on mast cells may be the result of an antigen‐independent production of IgE directed by the mast cells themselves and serving regulatory purposes, modifying the secretory response and preventing a massive possibly harmful degranulation.
Characterisation of isolates ofStaphylococcus aureusfrom acute, chronic and subclinical mastitis in cows in Norway
Authors: Tollersrud TORE , Kenny KEVIN , Caugant DOMINIQUE A. , Lund ARVE
Published: October 2003

Eighty‐sixStaphylococcus aureusisolates from cases of bovine mastitis were characterised biochemically and with respect to serotype, multilocus enzyme electrophoresis genotypes, antibiotic sensitivity, and production of enterotoxins A through D (SEA‐D) and toxic shock syndrome toxin‐1 (TSST‐1). The samples were obtained from 81 different cows from 79 Norwegian dairy herds in 10 different counties in southern Norway. There was an equal representation of isolates from cases of acute, chronic and subclinical mastitis. Multilocus enzyme electrophoresis using 13 genetic loci showed that 69 of 86 isolates had the same electrophoretic type. This common electrophoretic type comprised isolates that differed in the expression of other phenotypical characteristics studied. Fifty‐eight percent of the isolates produced one or more enterotoxins, predominantly a combination of SEC and TSST‐1. Capsular serotyping revealed that 95% of the isolates belonged to serotype 8. No correlation was found between the factors studied and the clinical classification of mastitis. It appears that the majority ofS. aureusisolates recovered from cases of bovine mastitis in Norway are genetically closely related and express common phenotypical characteristics.
Possible health impact of phytoestrogens and xenoestrogens in foodNote
Authors: Ibarreta Dolores , Daxenberger Andreas , Meyer Heinrich H. D.
Published: October 2003

Plants produce estrogen‐like substances, denominated phytoestrogens, which are present in many human foodstuffs. The consumption of phytoestrogens has been associated with a variety of protective effects. Their relative estrogenic potency combined with their concentrations in food and human plasma indicate biological relevance. However, their biological properties differ from those of estradiol or other endogenous estrogens in humans. For instance, their possible effects on SHBG, inhibition of steroid metabolizing enzymes, anti‐proliferative and anti‐angiogenetic and other side effects have been described. Furthermore, phytoestrogens can exert estrogenic and antiestrogenic activities at the same time and their potency and metabolism have not been yet elucidated in all cases. In recent decades growing evidence has accumulated on the hormone‐like effects of synthetic chemicals that appeared in the environment. The possible impact of xenoestrogens, to which humans are also exposed through the food chain, needs to be further clarified as well. The molecular effects and control mechanisms of these substances, their pharmacokinetics, threshold levels and dose‐response differences are issues that require further research before a full assessment of their effect on humans can be drawn. Evaluating the total exposure and impact of this estrogenic effect is very challenging because of the lack of specific knowledge in some areas and the differences in the biological activity among these substances, as pinpointed in this review.
Threshold analysis of selected dose‐response data for endocrine active chemicalsNote
Authors: Blair Robert M. , Fang Hong , Gaylor David , Sheehan Daniel M.
Published: October 2003

Using a biologically relevant mathematical model, the Michaelis‐Menten equation, we examined published data from endocrine active chemicals for evidence of no‐threshold dose‐response curves. Data were fit to a modified Michaelis‐Menten equation which accounted for total background response. Subsequently, the data sets were analyzed using non‐linear regression in order to estimate the four parameters of interest (non‐hormone controlled background (Bnh), maximum response (Rmax), endogenous hormone level (D0), and the dose at which a half‐maximal response was observed (ED50)) and to determine the fit to the fully modified Michaelis‐Menten equation. Subsequently, response data were adjusted to account for Bnh and then normalized to Rmax, while dose data were adjusted to account for D0 and then normalized to the ED50. This data set was combined into a single, composite data set and fit to the fully modified Michaelis‐Menten equation. We examined 31 data sets (24 endpoints) from studies on 9 different chemical/hormone treatments. Twenty‐six of the data sets fit the modified Michaelis‐Menten equation with high multiple correlation coefficients (r>0.90). The normalized data demonstrated a good fit to the modified Michaelis‐Menten equation. These results indicate that a variety of biological responses fit the modified Michaelis‐Menten equation, which does not have a threshold dose term.
Genetic variation in physiological sensitivity to estrogen in miceNote
Authors: Spearow Jimmy L. , O'Henley Peter , Doemeny Paul , Sera Robyn , Leffler Rachael , Sofos Taki , Barkley Marylynn
Published: October 2003

Genetic variation in susceptibility to endocrine disruption by estrogenic agents was examined in juvenile male mice. Mice were implanted with increasing doses of estradiol (E2) at 3 weeks of age and reproductive responses were determined 3 weeks later. Greater than 16‐fold differences in susceptibility to the disruption of reproductive development by E2 were detected between strains of mice. CD‐1 was much more resistant to the inhibition of testes weight, vesicular gland weight and spermatogenesis by increasing doses of E2. Spermatid maturation was eliminated by low doses of E2 in unselected strains such as C17/Jls and C57BL/6J. In contrast, widely used, large litter size selected CD‐1 mice showed little or no inhibition in spermatogenesis even in response to 16‐fold higher doses of E2. Testicular sulfotransferase activity (EST) per gram body weight was 3.5‐fold higher in untreated CD‐1 than in B6 strain males. This suggests that genetic differences in testicular EST activity may play a critical role in the detoxification of estrogens. These and other findings emphasize the need to identify and study genetic variation in sensitivity to estrogen in laboratory animal models used to assess the risk of xenobiotic estrogen exposure.
Immunolocalization of intercellular adhesion molecule‐1 and leukocyte functional associated antigen‐1 in schistosomal soluble egg antigen‐induced granulomatous hyporesponsivenessNote
Authors: Hassanein Hanaa , Hanallah Soad , El‐Ahwany Eman , Doughty Barbara , El‐Ghorab Nemat , Badir Bahaa , Sharmy Ragia , Zada Suher
Published: October 2003

In this work, the changes in expression of the adhesion molecules ICAM‐1/LFA‐1 on inflammatory cells of the liver were studied by immunohistochemistry. Mice sensitized with SEA and infected with S. mansoni and S. mansoni‐infected controls were examined from day 35 to day 56 postinfection. A significant upregulation of ICAM‐1 and LFA‐1 in both the SEA group and the infected control group started shortly after egg deposition at day 35 and persisted up to day 56 p.i. Notably, both ICAM‐1 and LFA‐1 expression peaks were shifted earlier to day 38 p.i. in the SEA group compared to day 40 in the infected control group. The distribution of ICAM‐1 and LFA‐1 in both groups was comparable. At the early phase of infection before granuloma formation, both ICAM‐1 and LFA‐1 were detected along the sinusoidal wall of small blood vessels. At the acute cellular granuloma phase, they were homogeneously distributed all over the inflammatory cells, while at the chronic fibrocellular stage a non‐homogeneous staining of granuloma cells at the periphery of the granuloma was apparent. The present data suggest that adhesion molecules play a role in the initiation and maintenance of granuloma formation. Thus, the granulomatous hyporesponsiveness induced by sensitization with SEA was associated with reduced expression of adhesion molecules.
Human herpesvirus 6 in the pathogenesis of multiple sclerosis
Authors: Enbom Malin
Published: October 2003

Multiple sclerosis (MS) is one of the most common disabling neurological diseases affecting young adults. It is a chronic disease characterised by inflammation and demyelination. The aetiology of MS is still unknown, but involvement of viruses has been suspected for many years. Recently much interest has focused on human herpesvirus 6 (HHV‐6), since the virus has been detected in MS plaques in the brain and patients with MS have been shown to have an aberrant immune response to HHV‐6. Results from different studies are, however, conflicting and in the light of the long list of previous claims to have found the viral aetiology of MS it is necessary to interpret the HHV‐6 findings with great caution. Possible mechanisms for virally induced demyelination and autoimmunity are discussed in this review, and the evidence for and against a role for HHV‐6 in MS is summarised.
RANTES in otitis media with effusion: Presence, role and correlation with cytokines and microbiology
Authors: Schousboe Lars Peter , Rasmussen Lars Melholt , Ovesen Therese
Published: October 2003

Various inflammatory cells and cytokines have been identified in otitis media with effusion (OME). The presence of neutrophils has been linked to interleukin‐8, but no chemotactic factor has as yet been identified for monocytes. The chemokine RANTES (Regulated upon Activation, Normal T Expressed and Secreted) attracts and activates primarily monocytes and may contribute to the pathogenesis of middle ear inflammation. We investigated the presence of RANTES by: 1) ELISA measurement in 114 middle ear effusions from children suffering from OME, 2) immunohistochemical localisation in experimental OME rabbit middle ear mucosa, and 3) expression in cultured rabbit middle ear epithelium in response to proinflammatory stimuli. RANTES was detectable in 94 (82%) of 114 effusions with a median concentration of 79.7 pg/mg total protein content. The concentration of RANTES was positively correlated with the endotoxin content. Immunohistochemically, RANTES was localized to the epithelial layer in experimental OME. In vitro, RANTES was expressed in middle ear epithelium in response to proinflammatory stimuli (TNF‐α) in a dose‐dependent manner. The expression of RANTES may explain the recruitment of monocytes in OME, possibly as a result of TNF‐α‐mediated endotoxin stimulation.
Immunohistochemical detection of Fas and Fas ligand in sarcomatoid renal cell carcinoma
Authors: Leroy Xavier , Wacrenier Agnes , De La Taille Alexandre , Gosset Pierre , Saint Fabien , Biserte Jacques , Gosselin Bernard
Published: October 2003

Sarcomatoid renal cell carcinomas (SRC) are rare neoplasms associated with a very poor prognosis. The aim of this study was to evaluate biomarker expression and clinical significance in this uncommon renal cancer. Cytokeratin, epithelial membrane antigen, vimentin, desmin, smooth muscle actin, CD34, S‐100 protein, MIB 1, p53, Fas and Fas ligand immunohistochemical expression was investigated in seven renal cell carcinomas with sarcomatoid changes. No significant difference between sarcomatoid and nonsarcomatoid areas was observed with the different biomarkers, excepted for Fas ligand. Fas expression was diffuse in sarcomatoid and nonsarcomatoid areas. However, Fas ligand had a higher expression in sarcomatoid in comparison to nonsarcomatoid areas. Our results showed that Fas and Fas ligand are both expressed in renal cancer. We suggest that the aggressive behavior of sarcomatoid carcinoma may be related to a higher expression of Fas ligand by tumor sarcomatoid cells. These findings may indicate that Fas ligand is a possible therapeutic molecular target for treatment of SRC.
Lymph node necrosis in systemic lupus erythematosusNote
Authors: KOJIMA MASARU , NAKAMURA SHIGEO , ITOH HIDEAKI , YOSHIDA KATSUE , SUCHI TAIZAN , MASAWA NOBUHIDE
Published: October 2003

The lymph node lesions of lupus lymphadenitis are characterized by necrosis sometimes accompanied by hematoxylin bodies, but only a few immunohistological analyses of this unique lesion have been reported. In this study we investigated the immunopathogenesis of these lesions. Lymph node specimens from four patients were analyzed immunohistochemically by applying recently developed monoclonal antibodies to immunocompetent cells. Necrosis occupied almost the entire lymph node in two cases (extensive type), whereas small foci of necrosis were found in the paracortex in the remaining two (localized type). No hematoxylin body formation was detected in any of the samples. Necrosis of the small muscular arteries, arterioles and venules was seen in the necrotic areas in all four cases. In one case of the localized type, necrotizing angitis was seen in a few arterioles and venules in the non‐necrotic area. By immunohistology, amorphous depositions of immunoglobulins and C3 were demonstrated in the walls of the arterioles and venules in two cases. Our findings indicate that vasculitis due to local deposition of immune complexes in the blood vessels may play an important role in the pathogenesis of necrosis in lupus lymphadenitis.
Tumor cell adhesion under hydrodynamic conditions of fluid flow
Authors: Haier Jörg , Nicolson Garth L.
Published: October 2003

Current evidence indicates that tumor cell adhesion to the microvasculature in host organs during formation of distant metastases is a complex process involving various types of cell adhesion molecules. Recent results have shown that stabilization of tumor cell adhesion to the microvascular vessel wall is a very important step for successful tumor cell migration and colonization of host organs. We are beginning to understand the influences of fluid flow and local shear forces on these adhesive interactions and cellular responses within the circulation. Mechanosensory molecules or molecular complexes can transform shear forces acting on circulating tumor cells into intracellular signals and modulate cell signaling pathways, gene expression and other cellular functions. Flowing tumor cells can interact with microvascular endothelial cells mediated mainly by selectins, but the strength of these bonds is relatively low and not sufficient for stable cell adhesions. Integrin‐mediated tumor cell adhesion and changes in the binding affinity of these adhesion molecules appear to be required for stabilized tumor cell adhesion and subsequent cell migration into the host organ. Failure of the conformational affinity switch in integrins results in breaking of these bonds and recirculation or mechanical damage of the tumor cells. Various cell signaling molecules, such as focal adhesion kinase, pp60src or paxillin, and cytoskeletal components, such as actin or microtubules, appear to be required for tumor cell adhesion and its stabilization under hydrodynamic conditions of fluid flow.
An enzyme‐based in situ hybridisation method for the identification of Streptococcus suisNote
Authors: MADSEN LARS W. , BOYE METTE , JENSEN HENRIK E.
Published: October 2003

A method for enzyme‐based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin‐fixed paraffin‐embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment protocols were applied to facilitate probe penetration and multiple detection systems were tested. The results were compared to those obtained by immunohistochemistry. Pretreatment was necessary to obtain a signal by in situ hybridisation. The use of proteinase‐K pretreatment was optimal regarding sensitivity and preservation of tissue morphology. A strong specific in situ hybridisation signal was achieved in tissue sections containing S. suis in microcolonies and the microanatomy of the surrounding tissue was easily assessed. However, the signal distribution differed from that found immunohistochemically and low‐grade infection could not be detected by in situ hybridisation. These findings were interpreted as reflecting the physiological state of the bacteria. Thus, this method could prove useful in future studies of the infection pathogenesis.
Killing of Gram‐positive cocci by fatty acids and monoglyceridesNote
Authors: BERGSSON GUDMUNDUR , ARNFINNSSON JÓHANN , STEINGRÍMSSON ÓLAFUR , THORMAR HALLDOR
Published: October 2003

The susceptibilities of three Gram‐positive cocci to medium‐chain saturated and long‐chain unsaturated fatty acids and their one‐monoglycerides were studied. The bacteria were incubated with equal volumes of lipid solutions for 10 min. Lauric acid, palmitoleic acid and monocaprin reduced the number of CFU by 6.0 log10 or greater at 5 mM concentration for streptococci of group A (GAS) and group B (GBS). When further compared at lower concentrations and after longer incubation time monocaprin proved to be the most active. Capric acid showed the highest activity against Staphylococcus aureus at 10 mM. However, at lower concentrations monocaprin was the only lipid that showed significant activity against S. aureus. The mode of action of monocaprin against GBS was studied by a novel two‐color fluorescent assay of bacterial viability and by electron microscopy. The results indicate that the bacteria are killed by disintegration of the cell membrane by the lipid, leaving the bacterial cell wall intact. The highly lethal effect of monocaprin indicates that this lipid might be useful as a microbicidal agent for prevention and treatment of infections caused by these bacteria.
Postmitotic basal cells in squamous cell epithelia are identified with Dolichos biflorus agglutinin – functional consequencesNote
Authors: HRDLIČKOVÁ‐CELA ENKELA , PLZÁK JAN , HOLÍKOVÁ ZUZANA , DVOŘÁNKOVÁ BARBORA , SMETANA KAREL
Published: October 2003

Dolichos biflorus agglutinin (DBA) is a plant lectin specifically recognizing α‐N‐acetylgalactosamine. Controversial reports regarding the binding of DBA to the epidermis have been published. Using a double labeling procedure at the single‐cell level, we studied the expression of DBA‐reactive binding sites in conjunction with markers of cell proliferation and differentiation in normal human epidermis, cornea, and malignant tumors as well as in cultured keratinocytes. The results characterize the cells recognized by DBA as postmitotic early differentiating cells, identifiable by their lack of expression of the proliferation marker (Ki‐67). The Golgi complex of a limited number of cultured keratinocytes was recognized by DBA and some of these cells show the accumulation of β1 integrin chain in the Golgi complex. This process seems to be important for the migration of postmitotic cells from the basal to the suprabasal layers.
High prevalence rates of adult silent coeliac disease, as seen in Sweden, must be expected in Denmark
Authors: WEILE BIRGITTE , GRODZINSKY EWA , SKOGH THOMAS , JORDAL ROBERT , CAVELL BERTIL , KRASILNIKOFF PETER A.
Published: October 2003

Aim: To disclose the prevalence of adult “silent” coeliac disease in Denmark and Sweden. Experimental design: 1573 Danish and 1866 Swedish healthy blood donors were screened for the presence of serum anti‐gliadin antibodies (AGA) by enzyme‐linked immunosorbent assay. AGA‐positive serum samples were further analysed for IgA anti‐endomysium antibodies (EmA) by indirect immunofluorescence microscopy. Main results: The Danish donor population had a higher mean age than the Swedish (41.4 years versus 37.6 years) and a higher proportion of females (41% versus 32%), and had a lower mean level of AGA (17.3 units versus 20.6 units). Sixty‐one (3.9%) Danish donors had AGA above the cut‐off limit, and four of these also had positive EmA tests. Sixty (3.2%) Swedish donors had AGA above the cut‐off limit, and five of these also had positive EmA. Coeliac pathology was proven by biopsy in all five coeliac disease‐suspected Swedish donors. No small intestinal biopsy was performed in the coeliac disease‐suspected Danish donors. Conclusions: Based upon the finding of EmA in AGA‐positive serum samples, silent coeliac disease may be suspected in 1 per 394 Danish blood donors (2.5 per 1,000). A similar rate was proven in 1 per 373 Swedish blood donors (2.7 per 1,000), indicating no major differences in the prevalence of adult silent coeliac disease between the two neighbouring countries.
Renal structures in type 2 diabetic patients with elevated albumin excretion rate
Authors: ØSTERBY R. , TAPIA J. , NYBERG G. , TENCER J. , WILLNER J. , RIPPE B. , TORFFVIT O.
Published: October 2003

Renal biopsies were obtained from type 2 diabetic patients with elevated albumin excretion. The aim was to obtain quantitative structural data to correlate with clinical findings. Biopsies from 27 diabetic patients and 12 non‐diabetic cases were analysed. Stereological methods were applied by light‐ and electron microscopy. Diabetic patients showed quantitatively markedly expressed diabetic glomerulopathy, but also an increase in glomerular volume, in prevalence of new‐vessel formation at the vascular pole, prevalence of glomerular occlusion and in interstitial volume fraction. A significant correlation was not observed between the degree of interstitial and glomerular involvement. The glomerular hypertrophy is interpreted as a compensatory phenomenon, leading to preservation of filtration surface in the open glomeruli. Close correlation was seen between glomerulopathy and glomerular function, and also with the stage of retinopathy. New vessel formation at the vascular pole was most frequent in patients with proliferative retinopathy. Signs of non‐diabetic glomerulopathy were not observed, but various atypical ultrastructural changes accompanying the advanced stages are illustrated. Our present findings correspond to data from type 1 diabetic patients. It is emphasised that all compartments of the kidney are affected by the diabetic state. It is suggested that the interstitial and glomerular lesions are influenced by different factors.
Stereological study of the cells of dorsal root ganglia in male diabetic rats
Authors: NOORAFSHAN A. , EBRAHIMPOOR M. R. , SADEGHI Y.
Published: October 2003

Most research on diabetes mellitus has focused on physiological and biochemical aspects of the peripheral nervous system, whilst little work has been done on morphological changes of the neurons. In the present study the effects of diabetes mellitus on cervical and lumbar dorsal root ganglia (C7 and L5) were investigated using modern stereological methods. Twelve adult male Sprague‐Dawley rats were randomly divided into two groups. Each group contained six male rats. Diabetes was induced in the experimental group by intraperitoneal injection of 50 mg/kg streptozotocin. At the end of 6 weeks, the rats were fixed by whole body perfusion transcardially with a buffered formalin solution. The seventh cervical and fifth lumbar dorsal root ganglia were removed and immersed in buffered formalin. After tissue processing, the ganglia were embedded in cylindrical paraffin blocks. Isotropic uniform random sections were obtained using the orientator method. Sections (5 μm thick) were selected and stained with Heidenhain's azan. Volume of perikarya of A‐ and B‐cells and their nuclei was estimated using the nucleator method. Before estimating the mean volume, the cells were sampled using the physical disector and point sampling method. Measurements showed that mean perikaryal and nuclear volume of A‐ and B‐cells of dorsal root ganglia (C7 and L5) was reduced in diabetic rats (p<0.05). B‐cell mean perikaryal volume in diabetic rats and A‐ and B‐cell mean nuclear volume were reduced by 66% on average. The mean volume of A‐cell perikarya was affected less than the others (average 33%). In addition, the difference between the perikaryal and nuclear volume of the seventh cervical and fifth lumbar dorsal root ganglia was not statistically significant. The present study, using stereological techniques, demonstrates reduced perikaryal and nuclear volume of the seventh cervical and fifth lumbar dorsal root ganglia in diabetic rats.
Long‐term studies of the juxtaglomerular apparatus in young microalbuminuric type 1 diabetic patients
Authors: GULMANN CHRISTIAN , ØSTERBY RUTH , BANGSTAD HANS‐JACOB
Published: October 2003

Aim: To determine the long‐term changes of the juxtaglomerular apparatus in incipient diabetic nephropathy. Methods: Three renal needle biopsies were performed on 15 young type 1 diabetic patients with microalbuminuria; at baseline and after an average of 2.4 and 8.2 years. Using light microscopy, 1 μm serial sections of the plastic‐embedded biopsies were investigated and volumes of the juxtaglomerular apparatus and glomerulus and areas of the macula densa and lumina of the afferent and efferent arterioles were measured. Results: From baseline to second follow‐up there was a significant decrease in JGA relative to glomerular volume. There was an increase in luminal area of the efferent arteriole which was paralleled by (non‐significant) changes in the afferent arteriole. Conclusion: Over a period of 8.2 years JGA size remained stable, but decreased relative to glomerular size. Also, an increase in luminal area was noted in efferent arterioles. This may be due to increased single nephron blood flow secondary to nephron loss.
Tumour necrosis factor‐α (TNF), lymphotoxin and TNF receptor levels in serum from patients with Wegener's granulomatosis
Authors: JÓNASDÓTTIR O. , PETERSEN J. , BENDTZEN K.
Published: October 2003

Wegener's granulomatosis (WG) is a systemic inflammatory disease with vasculitis as the key feature. Abnormal expression of tumour necrosis factor α (TNFα) is considered of prime pathogenic importance in several inflammatory diseases. The effects of TNFα are mediated by TNF receptors (TNF‐R), and these receptors are often found in soluble forms (sTNF‐R), which can modulate TNFα actions. To evaluate the clinical importance of the TNF family of cytokines, the serum levels of TNFα, TNFβ, now termed lymphotoxin (LTα), and sTNF‐R1 and sTNF‐R2 were measured by ELISA in 8 patients with WG during active disease and during immunosuppressive treatment, and in 11 healthy controls in parallel. Serum concentrations of TNFα were undetectable in all except two controls (18%) and three patients with WG (37%). After 7 days of therapy, six of the WG patients had measurable TNFα levels. Examination of the relative amounts of TNFα and sTNF‐R indicated that TNFα was mostly bound to its soluble receptors. In WG, the serum levels of sTNF‐R1 and sTNF‐R2 were dramatically increased (p<0.01), with little or no variation during treatment. While the IL‐1β levels did not deviate significantly from controls, the IL‐1ra levels were significantly elevated in the WG patients throughout the study period (p<0.01).