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PubMedDate not supplied

Vascular and parenchymal Abeta deposition in the aging dog: correlation with behavior.

The behavior of 25 dogs was indirectly assessed by a formal questionnaire (evaluation of Age-Related Cognitive and Affective Disorders-ARCAD), filled out by the owner. The density of diffuse and vascular deposits was evaluated using four anti-Abeta peptide antibodies, in four temporal areas. Parenchymal, diffuse deposits of Abeta42 peptide were found in all aged animals but one. They were Congo red negative and were not immunostained by the anti-Abeta40 antibody, contrary to the vascular deposits. The densities of vascular and parenchymal deposits were not correlated. The ARCAD score was correlated with age, density of Abeta parenchymal and vascular deposits, and with the number of areas containing deposits (extension index). Multivariate analysis showed that the age and the extension index explained most of the variance. Congo red positivity (indicating that the Abeta peptide has the characteristics of an amyloid substance) is limited in the dog to the vascular wall and is associated, as in man, with the deposition of the Abeta 1-40 isoform. Parenchymal Abeta deposition seems to be a common correlate of behavioral problems in aging dogs.

Aging↗
PubMed2001

Immunohistochemical investigation of the brain of aged dogs. I. Detection of neurofibrillary tangles and of 4-hydroxynonenal protein, an oxidative damage product, in senile plaques.

In the aging dog brain lesions develop spontaneously. They share some morphological characteristics with those of Alzheimer 's disease in man. Diffuse and primitive plaques are well known, whereas neuritic plaques rarely develop. Neurofibrillary tangles have not been seen in the canine. The aim of the present investigation was to study major age-related changes of the dog's brain using paraffin sections with respect to cross-immunoreactivity of tau, A beta protein and other immunoreactive components including hydroxynonenal protein, which is a marker for oxidative damage. The occurrence of neurofibrillary tangles and of the protein tau therein was studied in serial brain sections of two dogs with the Gallyas stain and by immunohistochemistry with three different antibodies against tau. Senile plaques were stained with a monoclonal anti-A beta (residues 8-17), polyclonal anti-apolipoprotein E and a monoclonal antibody against 4-hydroxynonenal (HNE). Amyloid deposits and controls were screened by Congo red staining viewed in fluorescent light, followed by polarized light for green birefringence. With the Gallyas stain and one of the antisera against tau, neurofibrillary tangles were revealed in a similar dispersed pattern, whereas the other antitau antisera gave negative results. With the anti-HNE a positive reaction was found in cerebral amyloid deposits and in vascular wall areas where amyloid deposition was confirmed by Congo-red staining, and in perivascular cells and in some neurons. These results indicate that the canine with his tangles and plaques which show oxidative changes, forms a spontaneous modelfor understanding the early changes and their interrelationships in Alzheimer's disease.

Aging↗
PubMed2002

Aggregation characteristics of ovalbumin in beta-sheet conformation determined by spectroscopy.

Protein misfolding and aggregation are involved in a number of the so-called "conformational" diseases (e.g., transmissible spongiform encephalopathies and Alzheimer disease). The development of rational strategies to interfere with aggregation is a potential therapeutic approach that requires complete knowledge of the aggregation process. We studied the aggregation of ovalbumin in beta-sheet conformation using mainly the spectral changes in the spectra of two dyes (Congo Red and pinacyanol) caused by the aggregates. We assumed a linear model of polymerization that fit to the experimental data. The critical aggregation constant, concentration of half-aggregation, nucleation parameter, growth parameter, and number of aggregation and free energy changes (total and per residue) were determined as aggregation-related parameters. Beta-Ovalbumin aggregates in a cooperative way. Moreover, the differences between such parameters obtained with Congo Red and pinacyanol suggest that each dye interacts with the protein in its own way.

Ovalbumin↗
PubMed1991

Case report of amyloidosis-like glomerulopathy with hepatic involvement.

A few cases of nephrotic syndrome with the glomerular deposition of an amyloid-like material which did not stain with Congo red have been documented. But extrarenal deposits have not been previously reported in this disease. We describe here a case of nephrotic syndrome associated with the deposition of an amyloid-like material in the liver as well as in the renal glomeruli. The deposits were made up of fibrillar structures which resembled those of amyloid when viewed through the electron microscope but they did not stain with Congo red. This is the first report of amyloidosis-like glomerulopathy with extrarenal deposits.

Amyloid↗
PubMed2002

Microglial activation and beta -amyloid deposit reduction caused by a nitric oxide-releasing nonsteroidal anti-inflammatory drug in amyloid precursor protein plus presenilin-1 transgenic mice.

3-4-(2-Fluoro-alpha-methyl-[1,1'-biphenyl]-4-acetyloxy)-3-methoxyphenyl]-2-propenoic acid 4-nitrooxy butyl ester (NCX-2216), a nitric oxide (NO)-releasing derivative of the cyclooxygenase-1-preferring nonsteroidal anti-inflammatory drug (NSAID) flurbiprofen, dramatically reduced both beta-amyloid (Abeta) loads and Congo red staining in doubly transgenic (Tg) amyloid precursor protein plus presenilin-1 mice when administered at 375 ppm in diet between 7 and 12 months of age. This reduction was associated with a dramatic increase in the number of microglia expressing major histocompatibility complex-II antigen, a marker for microglial activation. In contrast, ibuprofen at 375 ppm in diet caused modest reductions in Abeta load but not Congo red staining, suggesting that the effects of this nonselective NSAID were restricted primarily to nonfibrillar deposits. We detected no effects of the cyclooxygenase-2-selective NSAID celecoxib at 175 ppm on amyloid deposition. In short-term studies of 12-month-old Tg mice, we found that the microglia-activating properties of NCX-2216 (7.5 mg small middle dot kg(-1) small middle dot d(-1), s.c.) were present after 2 weeks of treatment. Microglia were not activated by NCX-2216 in non-Tg mice lacking Abeta deposits, nor were microglia activated in Tg animals by flurbiprofen (5 mg small middle dot kg(-1) small middle dot d(-1)) alone. These data are consistent with the argument that activated microglia can clear Abeta deposits. We conclude that the NO-generating component of NCX-2216 confers biological actions that go beyond those of typical NSAIDs. In conclusion, NCX-2216 is more efficacious than ibuprofen or celecoxib in clearing Abeta deposits from the brains of Tg mice, implying potential benefit in the treatment of Alzheimer's dementia.

Administration, Oral↗
PubMed1989

Histopathological study of corpora amylacea pulmonum.

In this paper, we present a rare disorder which is known as corpora amylacea pulmonum. X-ray CT scanning showed an abnormal focus of the lung as a solitary mass with high density and spicular features around the surface. The resected lung tissue was characterized by the appearance of round, concentrically laminated acellular bodies about 40-80 microns in diameter. The bodies were usually found lying free in the alveolar space and surrounded by the exudate alveolar macrophages or multinuclear giant cells. Some of these macrophages were in a state of progressive degeneration. The bodies showed an affinity for Congo red and exhibited partial birefringence. Moreover, all the bodies had a strong positivity for the PAS reaction and anti lysozyme antibodies. The exudate alveolar macrophages and multinuclear giant cells also displayed reactivity for PAS and lysozyme in a similar manner to that of the bodies. Electron microscopically the bodies were fundamentally composed of fibrillar elements, which bore some resemblance to amyloid fibrils and probably accounted for the partial affinity of the bodies for Congo red. These amyloid-like fibrils were also found in the cytoplasm of the macrophages. This suggested that the concentrically laminated bodies in corpora amylacea pulmonum might be formed by sequential aggregation, fusion, coalescence and compaction of degenerated alveolar macrophages.

Aged↗
PubMed2003

Beta-amyloid protein oligomers induced by metal ions and acid pH are distinct from those generated by slow spontaneous ageing at neutral pH.

Amyloid protein (Abeta1-40) aggregation and conformation was examined using native and sodium dodecyl sulfate/polyacrylamide gel electrophoresis, and the results compared with those obtained by atomic force microscopy, and with Congo red binding, sedimentation and turbidity assays. The amount of Abeta aggregation measured was different, depending upon the method used. Incubation for 15 min at pH 5.0 or in the presence of Fe2+, Cu2+ or Zn2+ did not alter the level of Abeta oligomers observed on SDS and native gels. However, the slow aggregation of Abeta to form high molecular mass species over 5 days was inhibited. In contrast, when Abeta aggregation was monitored using a Congo red binding assay or sedimentation assay, a rapid increase in Abeta aggregation was observed after incubation for 15 min at pH 5.0, or in the presence of Fe2+, Cu2+ or Zn2+. The low pH-, Zn2+- or Cu2+-induced Abeta aggregation measured in a turbidity assay was reversible. In contrast, a considerable proportion of the Abeta aggregation measured by native and SDS/PAGE was stable. Atomic force microscopy studies showed that Abeta aged at pH 5.0 or in the presence of Zn2+ produced larger looser rod-shaped aggregates than at pH 7.4. Abeta that had been aged at pH 7.4 was more cytotoxic than Abeta aged at pH 5.0. Taken together, the results suggest that Abeta oligomerizes via two mutually exclusive mechanisms to form two different types of aggregates, which differ in their cytotoxic properties.

Amyloid beta-Peptides↗
PubMed2007

Peculiar protein-protein interactions of the novel endoplasmic reticulum membrane protein Rcr1 and ubiquitin ligase Rsp5.

Overproduction of the ER membrane protein Rcr1 makes Saccharomyces cerevisiae resistant to Congo red by reducing the chitin content through a unknown mechanism. By both co-immunoprecipitation and yeast two-hybrid experiments, specific interaction between Rcr1 and the ubiquitin ligase Rsp5 was found. This binding was largely mediated by a singular VPEY sequence in Rcr1 in addition to PPSY, the consensus ligand motif of the WW domains. Mutant analysis indicated that Rsp5 and other Rcr1-interacting proteins discovered in the current screen were not engaged in Congo red resistance.

Endoplasmic Reticulum↗
PubMed2006

The secondary structure of pressure- and temperature-induced aggregates of equine serum albumin studied by FT-IR spectroscopy.

The protein aggregation is divided into amyloid fibrils and amorphous aggregates. Amyloid fibrils are composed of the 3-dimensional ordered structure and are bound to thioflavin T and Congo red dyes. The amorphous aggregates with the disordered structure do not bind to these dyes. We have investigated the pressure- and heat-induced aggregates of equine serum albumin (ESA) from the secondary structural viewpoint using FT-IR spectroscopy. We show the secondary structural differences between heat- and pressure-induced aggregates of ESA. The heat-induced irreversible aggregates of ESA are composed of the intermolecular beta-sheet structure without binding thioflavie T and Congo red to be amorphous form. On the other hand, the pressure-induced reversible aggregates are composed of the random structure to be also amorphous form. From the comparison of pressure effects on ESA in native and reducing conditions of disulfide bridges, we demonstrate that the restriction of structural flexibility by disulfide bridges is an important factor for the reversibility of the pressure-induced aggregation.

Animals↗
PubMed1994

Lymph node hyalinisation in rheumatoid arthritis and systemic sclerosis.

AIMS: To review the histological features of lymph nodes excised from seven patients with rheumatoid arthritis and one with systemic sclerosis. METHODS: Lymph nodes excised from seven patients with rheumatoid arthritis and one patient with systemic sclerosis over a 10 year period were examined using the stains haematoxylin and eosin, periodic acid Schiff (PAS), Masson-trichrome, and Congo red for amyloid. RESULTS: Of the seven nodes examined from the cases of rheumatoid arthritis, three showed definite reactive follicular hyperplasia with a prominence of plasma cells in the interfollicular areas, two showed subtotal replacement of the node by numerous sarcoid like granulomata, and one contained a large central area of necrosis with a surrounding palisade of histiocytes. In all six cases, focal areas of PAS positive eosinophilic hyaline material were present, which did not stain with Congo red. In some cases this hyaline material was focally calcified. In the seventh patient with rheumatoid arthritis the excised lymph node was almost totally replaced by similar PAS positive hyaline material which showed extensive areas of calcification. The lymph node removed from the patient with systemic sclerosis similarly showed almost total replacement by PAS positive hyaline material. CONCLUSION: In all cases the nodes contained PAS positive extracellular hyaline material to a greater or lesser degree. The lymph nodes from two of the patients with rheumatoid arthritis contained numerous sarcoid like granulomata, further indicating a possible association between sarcoidosis and rheumatoid arthritis. Pathologists and clinicians should include rheumatoid arthritis and systemic sclerosis in their differential diagnosis of lymph node hyalinisation of unknown aetiology.

Adult↗
PubMed1994

Non-fibrillar beta-amyloid protein is associated with smooth muscle cells of vessel walls in Alzheimer disease.

Meningeal blood vessels were studied in Alzheimer disease (AD) and control brain specimens obtained from autopsies within 16 hours after death. Serial sections were stained with thioflavine S and Congo red and immunostained for the presence of beta-amyloid precursor protein (beta PP) and beta-protein and for smooth muscle-specific proteins myosin, alpha-actin, and desmin. Isolated blood vessels were studied by immunoblotting for the presence of beta PP, fragments of beta PP, and beta-protein. The arteries that were strongly immunopositive for beta-protein in all layers of the walls were also positive for amyloid fibrils on thioflavine S and Congo red stainings. The focal immunostaining for beta-protein in less affected vessels was located in the tunica media in the cytoplasm of smooth muscle cells or formed granules between myocytes. The cytoplasmic beta-protein and some of the small deposits present between cells were negative for amyloid fibrils. The vessels isolated from specimens containing beta-protein-immunoreactive material contained 3 kD, 4.2-4.5 kD, 8.5-9 kD, and 17.5 kD beta-protein-immunoreactive bands. These bands were not found in the samples assessed as beta-protein-negative by immunocytochemistry. These data indicate that during formation of amyloid in AD vessel walls, nonfibrillar, monomeric, and oligomeric beta-protein accumulate.

Alzheimer Disease↗
PubMed1998

Clinical benefits of diagnosing incipient AA amyloidosis in pediatric rheumatic diseases as estimated from a retrospective study.

OBJECTIVE: The diagnosis of AA amyloidosis could not be made in eight patients with pediatric rheumatic diseases as later verified employing the more sensitive combination of Congo red and additional immunocytochemistry (CRIC). The objective of this paper is to estimate the benefit of CRIC by reevaluating the historical charts with respect to the question as to which of the diagnostic and therapeutic measures would have been altered if the correct diagnosis had been known at the time of the primary biopsy. METHODS: All subsequent biopsies of eight children with historically missed AA amyloidosis in their primary biopsies were retrieved, together with the historical data including the Congo red stains of the biopsies. The biopsies were reexamined blindly for the presence of amyloid and the results were compared with the historical data concerning diagnostic and therapeutic measures. RESULTS: Using CRIC, AA amyloidosis could be identified an average of approximately three years earlier as compared to the historical data. This gain in time would certainly have altered the diagnostic as well as the therapeutic options, i.e. 10 out of 21 biopsies would have been spared and the earlier diagnosis would have initiated more significant antiinflammatory therapy. CONCLUSION: Very early detection of amyloid reduces the diagnostic burden and unveils an option for a consequent antiinflammatory therapy very early in the course of AA amyloidosis.

Amyloidosis↗
PubMed1980

Studies on acid protease fractions and gastric mucosal atrophy. 3. Special reference to peptic ulcers.

In combination with routine gastric secretion test and endoscopic congo red test, alkali labile pepsin (ALP) and alkali stable pepsin (ASP) were separately determined in total of 41 patients with peptic ulcer including 20 gastric (GU), 12 duodenal (DU) and 9 gastroduodenal ulcers (GDU), and in 10 normal controls. In both of basal and tetragastrin stimulated states, percent of ASP in total acid protease (%ASP) was increased in order of GU, GDU, normal control and DU with a close relation to the dimension of acid secreting area determined by endoscopic congo red test. Percent ASP was decreased after tetragastrin provocation in all disease groups. GU had high % ASP and low maximal acid output (MAO), GDU had high %ASP and high MAO, and DU showed low %ASP and high MAO.

Adult↗
PubMed1989

Campylobacter pylori, duodenal ulcer, and gastric metaplasia: possible role of functional heterotopic tissue in ulcerogenesis.

Multiple pinch biopsies were taken from the duodenum and antrum of 137 subjects (46 active duodenal ulceration; 44 healed ulcers; 47 'normal'), and examined for the presence and grade of gastritis, gastric metaplasia, and Campylobacter pylori. These factors, as well as age, sex, cigarette, and anti-inflammatory agent intake were evaluated as possible risk factors for duodenal ulceration. Pentagastrin induced Congo Red staining of the duodenal bulb was performed in an additional 43 cases, to determine the presence of functioning parietal cells in the duodenum. Ninety eight per cent of patients with duodenal infection with C pylori had active or healed duodenal ulcers. Bacteria were confined to areas of gastric metaplasia which was always infiltrated with inflammatory cells. The metaplastic tissue was usually superficial in type, although patients had C pylori associated with heterotopic tissue: this has not been previously described. Congo Red staining of the duodenal bulb showed that functioning endogenous acid producing tissue could be found most often at the edges of duodenal ulcers, but also in non-ulcer subjects. Cigarette smoking, age, sex, and ingestion of non-steroidal anti-inflammatory agents were not to be found to be significant risk factors for duodenal ulceration. In contrast, the presence of duodenal infection with C pylori proved to be a strong risk factor for duodenal ulceration (RR = 51), together with gastric metaplasia (RR = 6.2), and antral C pylori infection (RR = 7.6). These data identify duodenal infection with C pylori as the strongest risk factor for development of duodenal ulceration. Our finding of endogenous acid production around the edges of duodenal ulcers suggests an active role for parietal cells in the duodenum. We postulate a synergistic role for duodenal C pylori and endogenous acid production in the development of duodenal ulceration.

Adult↗
PubMed1999

Inhibition of elastase-induced acute inflammation and pulmonary emphysema in hamsters by a novel neutrophil elastase inhibitor FR901277.

OBJECTIVE AND DESIGN: A neutrophil elastase inhibitor FR901277 was examined for its inhibitory effect on degradation of natural substrate elastin in vitro, and on acute inflammatory states and pulmonary emphysema in vivo. MATERIAL AND TREATMENT: Elastin-congo red was used as a substrate for elastin degradation assay. Paw edema in male C57BL mice (6 weeks old) and pulmonary hemorrhage in female golden hamsters (5 weeks old) were induced by topical injection of human neutrophil elastase (HNE). Pulmonary emphysema in male golden Syrian hamsters (10 weeks old) was provoked by intratracheal instillation of porcine pancreatic elastase. In all in vivo experiments. FR901277 was administered prior to elastase treatment. METHODS: Elastin degradation by HNE was monitored spectrophotometrically with elastin-congo red. Foot swelling was measured by calipers. Pulmonary hemorrhage was assessed by hemoglobin concentration in bronchoalveolar lavage fluid. As emphysematous parameters, quasi-static lung compliance and vital capacity were measured. RESULTS: FR901277 inhibited HNE-induced elastin degradation. Systemic treatment with FR901277 significantly inhibited paw edema and pulmonary hemorrhage. Intratracheal treatment with FR901277 significantly ameliorated changes in pulmonary function. CONCLUSIONS: These results suggest that FR901277 inhibits the elastase activity potently both in vitro and in vivo, and that elastase may play a role at least in part in pathogenesis of pulmonary emphysema.

Amides↗
PubMed1987

Inhibition of yeast binding to mouse peritoneal macrophages by wheat germ agglutinin: a novel effect of the lectin on phagocytic cells.

The ability of wheat germ agglutinin (WGA) to enhance the binding of bacteria and tumor cells to phagocytic cells, and to induce the killing of tumor cells by macrophages and monocytes, is well established. We observed, however, that WGA inhibits the binding to and phagocytosis of yeast cells by thioglycolate-elicited murine peritoneal macrophages. In order to follow these processes rapidly, the yeasts were labeled with Congo-red and their binding to the macrophages was measured spectrophotometrically after treatment with sodium dodecylsulfate. Phagocytosis was also followed by light microscopy. Binding of the yeasts was inhibited by about 80% after pretreating the macrophages with 150 micrograms/ml of WGA. This effect was reversed by subsequent incubation with N-acetyl-D-glucosamine, chitobiose or chitotriose, but was unaffected by methyl alpha-D-mannoside, N-acetyl-D-mannosamine, D-mannose or D-galactose. Pretreatment of the Congo-red yeasts with WGA did not inhibit their binding by the macrophages. Of a variety of lectins tested, only WGA and Datura stramonium lectin had this effect. Pretreating the macrophages with sialidase prevented the inhibition induced by WGA. Our findings suggest the presence on the macrophages of a class of WGA receptors not previously reported.

Animals↗
PubMed2004

Histochemical accumulation of oxidative damage products is associated with Alzheimer-like pathology in the canine.

An important lesion in Alzheimer's disease (AD) patient brains is the neurofibrillary tangle (NFT). Hyperphosphorylated tau is its major component. In a former paper we described some NFT in the canine brain. During aging, moreover, advanced glycation end products (AGE) might accumulate. Glycated tau induces lipid peroxidation in vivo and tau and AGE antigens have been mentioned to co-localize in NFT. This indicates that AGE may play an important role in Alzheimer disease (AD) by oxidation of tau. The aim of the present study was to investigate amyloid, neurofibrillary tangles, Abeta precursor protein, Abeta, tau, ubiquitin, advanced glycation end products, 4-hyroxynonenal protein and lipofuscin in a series of dogs of varying ages. The results showed a significant positive correlation between age and amyloid quantity (Congo red staining), HNE staining and lipofuscin (LF), and between amyloid quantity and HNE staining and LF. Staining for AbetaPP seemed to have a tendency to increase with age, whereas staining for tau, ubiquitin and AGE each only gave limited positive results in a proportion of the older dogs. Preliminary studies including loss of cognitive capabilities in the older dogs and chemical measurement of lipofuscin-like pigment (LFP) accumulation in brain extracts revealed an increase with old age and dementia. The Congo red, HNE and LF results suggest that deposition of amyloid with aging might be associated with formation of end products of lipid peroxidation. The finding of the limited positive signals for tau, ubiquitin and AGE in some old cases might indicate that the spontaneous brain pathology of the aged dog reveals similarities to early stages observed in AD in humans especially those with Down syndrome.

Aging↗
PubMed1993

Phase variation of slime production in Staphylococcus aureus: implications in colonization and virulence.

Two methods commonly used for slime detection in coagulase-negative staphylococci (tube biofilm formation and colony morphology in Congo red agar) were used to study 144 ruminant mastitis Staphylococcus aureus strains. Slime production was detected in 21 strains. A majority of cells (85%) in slime-producing (SP) strains and a minority of cells (5%) in non-slime-producing (NSP) strains showed a condensed exopolysaccharide matrix (slime) surrounding the bacterial cell wall, as revealed by electron microscopy and immunofluorescence. In vivo slime production was also detected immunohistochemically after experimental infection of the mammary gland in sheep. Upon repeated subcultures in Congo red agar, NSP variants were obtained from four ovine and four bovine SP strains at a frequency ranging from 0.5 x 10(-4) to 10(-4). Because SP variants could not be obtained from NSP strains within this range or at a higher frequency, they were obtained by the tube biofilm formation (requiring repeated subculturing of NSP strains in tryptic soy broth containing 2% glucose for subsequent recovery of colonies adherent to the walls of the culture tubes). In experimental challenge, the SP variant showed a significantly higher colonization capacity than did the NSP variant of the same strain used (P < 0.001). However, the NSP variant had a higher virulence than did the SP variant (P < 0.001). These results may help to explain the different roles of S. aureus slime production cell types (SP and NSP) coexisting in disease.

Animals↗