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PubMedDate not supplied

Amyloid in cytologic specimens. Differential diagnosis and diagnostic pitfalls.

OBJECTIVE: To describe and illustrate the characteristic features of amyloid in cytologic preparations and point out its diagnostic pitfalls. STUDY DESIGN: Five fine needle aspirates and one bronchial washing that contained amyloid were retrospectively reviewed. The aspirates were obtained from each of the five following sites: lung, occipital lymph node, thyroid gland, proximal humerus and subcutaneous soft tissue. Smears of all of the aspirates were stained with Papanicolaou stain, and in two cases they were also stained with Diff-Quik. Cell block sections were stained with hematoxylin and eosin. Congo red, CD45 and CD20 were used on selected cases. RESULTS: Amyloid appears as either flocculent material or irregularly shaped fragments with scalloped and pointed edges. The amorphous fragments are acellular and frequently associated with connective tissue cells. They stain eosinophilic to cyanophilic with Papanicolaou stain and deep blue with Diff-Quik. In two cases an exuberant giant cell reaction almost obscured the amyloid. In the thyroid aspirate, the amyloid was misinterpreted as colloid. In bronchial washings and lung aspirates, amyloid has to be distinguished from mucus, alveolar proteinosis, chondroid material and corpora amylacea. When circumferentially surrounded by lymphocytes or plasma cells, flocculent amyloid deposits may simulate adenoid cystic carcinoma. CONCLUSION: Amyloid can be easily overlooked or mistaken for other entities with similar staining qualities. Congo red staining can help to confirm the diagnosis.

Aged↗
PubMed2001

[Analysis of mouse model exhibiting neurofibrillary changes].

Dysfunction and filamentous microtubule-binding tau protein are key markers of neurodegenerative pathologies, including the pathology and neural degeneration associated with Alzheimer's disease (AD). Immunocytochemical studies of NFT-bearing neurons showed that NFTs are composed of ubiquitin and phosphorylation-dependent tau. Congo-red birefringency and thioflavin-S reactivity in NFT-bearing neurons also demonstrated that the tau aggregation forms a beta-sheet structure. Discovery of the molecular mechanisms of NFT formation may lead to more insight about events occurring during neurodegeneration. In frontotemporal dementia parkinsonism 17 (FTDP17), genetic studies indicated that tau is a causative gene, and mutation is found in exons and introns of tau gene. A patient who possesses this mutation exhibits pathologically NFT and clinically personality change and cognitive dysfunction. Then, we produced the Tg mice expressing human longest tau with missense mutation V337M. In the present study, neurons of hippocampus and cerebral cortex in our Tg mice showed phosphorylated and ubiquitinated tau aggregations with a beta-sheet structure. This was demonstrated by Congo-red and thioflavin-S positive staining, a histological criterion used to identify NFTs observed in neurodegenerative disorders. The mice also displayed altered behaviors that were associated with NFT formation. Thus, V337M mice provide a first animal model exhibiting altered behavior due to NFTs.

Animals↗
PubMed2001

Improvement of melatonin to the learning and memory impairment induced by amyloid beta-peptide 25 - 35 in elder rats.

AIM: To investigate improvement of melatonin on learning and memory impairment induced by amyloid beta-peptide 25 - 35 (Abeta25-35) in elder rats. METHODS: Step-down type passive avoidance test, shuttle-box test, and Morris water maze were used together to determine effects of Abeta25-35 and melatonin on learning and memory. Pathological changes were observed by HE, Congo red, and Ag staining. RESULTS: The elder rats were injected bilaterally Abeta25-35 20 microg into the hippocampus to induce learning and memory dysfunction. Melatonin administration (0.1, 1, and 10 mg/kg, ig x 8 d) to the Abeta25-35-treated rats prolonged the latency, shortened the total stimulating time, and decreased the number of errors in the step-down test. Shuttle-box test showed that melatonin improved amnesic rats' performance at the same doses. Melatonin (0.1, 1, and 10 mg/kg ), giving for 10 d, could enhance the spatial resolution of amnesic rats in Morris water maze test. Also in Abeta25-35-treated group, a decrease in the number of neurons in cortex and hippocampus, a massive glial reaction, and neurophilic phenomenon were detected by HE staining; the positive vascular amyloidosis by Congo red and fibrils by Ag staining were observed. Melatonin (0.1 and 1 mg/kg)could inhibit above pathological changes in Abeta25-35 group. CONCLUSION: Melatonin improved the impaired learning and memory induced by Abeta25-35 in elder rats.

Amyloid beta-Peptides↗
PubMed1982

The release of 4,4'-diaminobiphenyls from azodyes in the rat.

Six azodyes derived from benzidine, o-tolidine or o-dianisidine were separately administered orally by gavage to rats. Urine was collected over a 24 h period. Following dichloromethane extraction, urines were analysed by h.p.l.c. for the presence of the respective parent amine and its N-acetylated and N,N'-diacetylated derivatives. After alkaline hydrolysis, urines were analysed for the amines resulting from the cleavage of N-conjugates. All six dyes, direct black 38, direct brown 95, direct blue 6, Congo red, trypan blue and Chicago sky blue were found to be reduced, N-acetylated and N-conjugated. However, no N,N'-diacetylated metabolites were detected. After administration of the same dyes via injection into the hepatic portal vein, bile was collected over a 3 h period by cannulation of the bile duct. Urine was withdrawn from the bladder by syringe at the end of the three hours. Both body fluids were analysed for reduction products which were found only in the case of direct black 38, direct brown 95 and direct blue 6. Of the six dyes examined only the three direct dyes were mutagenic to S. typhimurium strains TA98 and TA1538 in the absence of flavin mononucleotide. The same three dyes were also substrates for rat liver microsomal azoreductase enzymes whereas Congo red, trypan blue and Chicago sky blue were shown to be inactive in a previous publication. The possible relationship between these results and the potent carcinogenicity exhibited by direct black 38, direct blue 6 and direct brown 95 is discussed.

Aminobiphenyl Compounds↗
PubMed1983

Unanticipated amyloidosis in dogs infused with insulin.

Highly purified regular porcine insulin was given by portable insulin pumps through indwelling vena caval catheters to 17 (13 normal, and 4 pancreatectomized) dogs initially weighing 15 +/- 2 kg at rates ranging from 2 to 10 mU/min (total 17-250 mg) over time periods ranging from 37 to 252 days. During the course of the study, many of the animals lost weight and became anemic. Since these conditions persisted and weight loss progressed even after cessation of insulin infusion, as many of the dogs as possible (15 of 17) were autopsied for microscopic studies. Large amounts of amyloid were demonstrated in the liver, kidney, spleen, and/or pancreas in 55% (6/11) of normal, and in 75% (3/4) of pancreatectomized dogs. The amyloid deposits were Congo red positive, exhibited classical apple green fluorescence under polarized light, and possessed the characteristic ultrastructural features of amyloid. Massive deposits of amyloid were observed in animals receiving as little as 17 mg of insulin over a time span of 52 days. In those animals with hepatic amyloid, marked hepatomegaly was present (i.e., 1200 +/- 250, X +/- SD, versus 300 +/- 25 g for normal animals) and preterminal serum alkaline phosphatase levels were markedly elevated (434 +/- 285 versus 30 +/- 14 IU/L for animals without hepatic amyloid). The magnitude of the hepatic amyloid deposits precludes the possibility that they represent insulin aggregates or insulin-derived products per se. No evidence of amyloid was present in any of the tissue biopsy specimens obtained prior to insulin infusion. Moreover, the possibility that this represents an immune response to the injected porcine insulin has to be viewed in light of the fact that the amino acid sequences of dog and porcine insulins are identical. It is of particular interest that the affinity of the amyloid deposits for Congo red stain was totally abolished by prior permanganate treatment, suggesting that the amyloid was derived from serum amyloid A protein rather than from immunoglobulin light chains or insulin aggregates per se. Further evidence that the protein was of the AA-type came from the initial biochemical characterization. Gel filtration on Sephadex G100 in 6 M guanidine hydrochloride identified two small molecular weight peaks of about 13,000 and 25,000 daltons, both of which inhibited the radioimmunoassay for human AA protein.(ABSTRACT TRUNCATED AT 400 WORDS)

Amyloid↗
PubMed1989

Outer membrane peptides of Yersinia pestis mediating siderophore-independent assimilation of iron.

It is established that wild-type cells of Yersinia pestis absorb exogenous hemin or Congo red and thus grow as pigmented colonies at 26 degrees C on media containing these chromatophores (Pgm+). Pgm+ isolated are known to possess a siderophore-independent mechanism of iron-transport (required for growth in iron-deficient medium) which is absent in avirulent Pgm- mutants. Production of the bacteriocin pesticin and linked invasins (Pst+) is an additional defined virulence factor of yersiniae; mutation of Pgm+,Pst- organisms to pesticin-resistance (Pstr) results in concomitant conversion to Pgm-. In this study, autoradiograms of two-dimensional gels of [35S]methionine-labeled outer membranes from Pgm- mutants were compared to those of the Pgm+,Pst+ or Pgm+,Pst- parent. An apparently single predominant peptide present in these preparations (greater than 10% of total membrane protein) existed as a family of iron-modifiable 17.9-kDa molecules focusing down to isoelectric points of about 4.6 and up to 5.89. Expression of eight detectable Pst(+)-specific peptides was not significantly influenced by exogenous iron. Pgm+ yersiniae constitutively produced pigmentation-specific peptide F and five iron-repressible peptides termed IrpA to IrpE. Typical spontaneous mutation to Pgm- resulted in loss of peptide F and IrpB-E. A rare Pgm+,Pstr mutant, selected on Congo red agar containing pesticin, also lost IrpB-E but retained peptide F. This isolate, like Pgm- mutants, failed to grow in iron-deficient medium. Regardless of phenotype, all yersiniae utilized hemin, hemopexin, myoglobin, hemoglobin, and ferritin, but not transferrin or lactoferrin, as sole sources of iron.

Bacterial Outer Membrane Proteins↗
PubMed1998

Development of gastrointestinal beta2-microglobulin amyloidosis correlates with time on dialysis.

Dialysis-associated beta2-microglobulin (beta2m) amyloidosis affects predominantly musculoskeletal tissue, but visceral involvement also occurs. To evaluate the clinical significance and prevalence of gastrointestinal beta2m amyloidosis, we studied hemodialysis patients admitted for gastrointestinal-related complaints. Hemodialysis patients (excluding those with non-beta2m amyloidosis) who were admitted with gastrointestinal complaints from 1984 to 1994 were identified. Gastrointestinal tissues from patients with available autopsy or surgical specimens were examined using hematoxylin and eosin stain, Congo red stain, and beta2m immunostain. Each case was evaluated independently by two pathologists and scored for quantity and location of beta2m amyloid and associated pathology. Of 24 patients, eight (four men and 4 women) had beta2m amyloid deposits within the gastrointestinal tract. Acute clinical presentation ranged from abdominal pain to gastrointestinal bleeding and was not significantly different for patients with or without gastrointestinal beta2m amyloid deposits. However, the mean time on dialysis of 15.3 +/- 5.7 years (range 6-24 years) for patients with gastrointestinal beta2m amyloidosis was significantly greater than that of patients without gastrointestinal beta2m amyloidosis (10.5 +/- 7.0 years, range <1 to 22 years, p < 0.05). Vascular histopathology ranged from mild focal thickening of vessel walls to massive vascular beta2m amyloid deposition with thrombosis. Extravascular beta2m amyloid ranged from mild to severe with marked expansion of the submucosa. Mucosal pathology ranged from none to severe ulceration. The degree of beta2m amyloid and the associated pathology tended to increase in severity with time on dialysis. Gastrointestinal beta2m amyloid deposition is an underappreciated complication of chronic hemodialysis that is significantly associated with increased time on dialysis. Gastrointestinal beta2m amyloidosis should be considered in any patient on hemodialysis 10 years or more who has gastrointestinal symptoms and can be identified in resection specimens as well as some biopsy specimens. Congo red stain and beta2m immunostains may be necessary for sensitive histopathologic evaluation of gastrointestinal beta2m amyloidosis.

Adult↗
PubMed1978

Corpora amylacea in mesothelioma of the atrioventricular node.

Rounded or polyhedral, acellular, dense lamellated structures were seen within gland-like spaces in a case of atrioventricular mesothelioma. These structures exhibited many of the histochemical characteristics of amyloid, viz., pink colour with green birefringence and bright red fluorescence with alkaline Congo red; ortochromasia and red birefringence with standardised toluidine blue; positive DMAB-nitrite and diazotisation coupling reactions and spontaneous autofluorescence. It is suggested that these bodies are derived from spontaneous assembly or polymerisation of microfibrils of desquamated cells lining the cystic spaces of the tumour as occurs in prostatic corpora amylacea. The peculiar intramyofibre proliferation of tumour cells in the peripheral part of the tumour suggests that viable tumour cells can penetrate, survive and proliferate within atrial or nodal myofibres leaving an intact sarcolemmal sheath. The slow tumour cell growth and the successive degeneration of central tumour cells may explain the tubular and/or glandular pattern constantly seen in this tumour.

Aged↗
PubMed1982

beta-Fibrillary bodies in low-grade adenocarcinoma of parotid gland: a histochemical and ultrastructural study.

Rounded or polyhedral, acellular, dense lamellated structures were seen within the cystic and glandular spaces in a case of low-grade papillary adenocarcinoma of the parotid gland. These structures displayed the histochemical characteristics of amyloid, namely, pink color with apple-green birefringence and bright red fluorescence with alkaline congo red, orthochromasia and red birefringence with standardized toluidine blue, positive dimethylaminobenzaldehyde nitrite and diazotization coupling reactions, and spontaneous autofluorescence. At the ultrastructural level the tumor consisted of cuboid, flattened, or elongated epithelial cells with varying degrees of differentiation, but most mature tumor cells had numerous intracellular intermediate filaments. These filaments were randomly oriented and had no lateral fasciation; they were 10 nm wide and similar to those constituting the intraluminal corpora amylacea. These bodies displayed increased fibrillary density. Cellular organelles and pyknotic nuclei were frequently present at the periphery of the fibrillary masses. Amyloid masses, histochemically and ultrastructurally indistinguishable from those in the lumens, were present in the stroma as well. It is postulated that both stromal and intraluminal beta-fibrillary bodies result from apoptosis and desquamation of neoplastic cells, with progressive release and confluency of intracellular intermediate filaments within closed cystic spaces. This additional evidence of beta-fibrillosis associated with a slow-growing non-hormone-secreting salivary gland tumor suggests that these tumors may be associated with amyloidosis more frequently than was previously suspected.

Adenocarcinoma, Papillary↗
PubMed1978

Corpora amylacea in adenolymphoma (Warthin's tumor).

Round or polyhedral, acellular, lamellated or amorphous eosinophilic structures were observed in the cystic spaces of adenolymphomas. These eosinophilic bodies ahd several of the histochemical characteristics of amyloid, viz., pink color with green specific birefringence and bright red fluorescence with alkaline Congo red; positive DMAB-nitrite and DC reactions, and spontaneous autofluorescence. It is suggested that these bodies are derived from spontaneous assembly or polymerization of microfibrils of desquamated epithelial cells lining the cystic spaces of the tumor, as has been described to occur in prostatic corpora amylacea.

Adenolymphoma↗
PubMed2004

Formation of amyloid fibrils from fully reduced hen egg white lysozyme.

The fully reduced hen egg white lysozyme (HEWL), which is a good model of random coil structure, has been converted to highly organized amyloid fibrils at low pH by adding ethanol. In the presence of 90% (v/v) ethanol, the fully reduced HEWL adopts beta-sheet secondary structure at pH 4.5 and 5.0, and an alpha-to-beta transition is observed at pH 4.0. A red shift of the Congo red absorption spectrum caused by the precipitation of the fully reduced HEWL in the presence of 90% (v/v) ethanol is typical of the presence of amyloid aggregation. EM reveals unbranched fibrils with a diameter of 2-5 nm and as long as 1-2 microm. The pH dependence of the initial structure of the fully reduced HEWL in the presence of 90% (v/v) ethanol suggests that Asp and His residues may play an important role.

Amyloid↗
PubMed2002

Morphology of the cricopharyngeal muscle in Zenker and control specimens.

The cricopharyngeal muscle (CPM) is essential for normal deglutition. Pharyngeal dysphagia commonly results from impaired or uncoordinated CPM dilation. Dysfunction of the CPM has also been implicated in the genesis of Zenker's (pharyngoesophageal) diverticulum. Despite the CPM's significance, little is understood about its morphology. We studied CPM biopsy specimens from 20 patients with Zenker's diverticulum and from 5 fresh cadaver patients with detailed histologic techniques to include fiber size and shape and adenosine triphosphatase, reduced nicotinamide adenine dinucleotide, trichrome, succinate dehydrogenase, cytochrome C oxidase, periodic acid-Schiff reaction, oil red O, acid phosphatase, Congo red, crystal violet, and monoadenylate deaminase stains. The normal CPM has unique morphological characteristics, with some myofibers having staining properties that are a hybrid between striated muscle and muscle spindle. The variable orientation of the muscle fibers is also different from that of most other striated musculature. Of the 20 Zenker CPM specimens, 4 specimens did not reveal any significant differences from controls (2 of which had insufficient amounts of tissue for complete analysis). In the remaining 16 specimens, several abnormalities existed, including excessive size variation (16/16), grouping of atrophic fibers (9/16), target or targetoid formations (4/16), cores (2/16), and ragged red fibers (2/16). The final pathological pattern of the 16 specimens was neurogenic in 7, myopathic in 4, and mixed (with neurogenic predominance) in the remaining 5. Two specimens contained significant lymphocytic inflammatory infiltrates. We conclude that the unique neuromuscular function of the CPM in deglutition is likely due to its fiber orientation and the hybrid nature of some of the myofibers. Morphological disturbances of the CPM impair its dilation and may account for the development of Zenker's diverticulum. This disturbance is most often due to progressive denervation of the CPM.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Amyloidosis of the iris and sclera in the pathogenesis of glaucoma].

Morphological analysis of 173 biopsies of the iris and sclera removed during antiglaucoma operations in 115 patients with open angle glaucoma showed extracellular deposits of amyloid in 44.4% of cases, which complicated the course of glaucomatous process and had pathogenetic importance. Amyloid was identified by Congo red [correction of Congo-rot] staining with the control in the polarized light and also by toluidine blue staining for chondroitin and dermatan sulfates. The vascular and muscle (pupillary muscle) forms of amyloidosis were found in the iris and the pericollagen and focal forms in the drainage system and sclera. We propose to classify the amyloid form of glaucoma with specific morphological picture.

Adult↗
PubMed2003

Plasma cell myeloma producing IgG, IgM, and IgA immunoglobulins in a cow.

A diagnosis of plasma cell myeloma was made in a 6-year-old Holstein cow that showed continuous nosebleed, progressing emaciation, and hyperglobulinemia. Necropsy revealed enlargement of the caudal mesenteric lymph nodes. Lymph nodes and spleen were infiltrated by neoplastic plasma cells. Renal lymph nodes, bone marrow, and kidneys also were affected. Amyloid-like material that was negative for Congo red was present in most of the affected lymph nodes. Congo red-positive amyloid material was noted in spleen, kidneys, liver, and adrenal glands. Neoplastic plasma cells exhibited immunohistochemical reactions for lambda-light chain and 3 classes of heavy chain but not for kappa-light chain. Nonamyloid deposits were labeled with antisera against lambda-light chain and heavy chains. Plasmacytoid cells, which stained positively for IgG, IgM, or IgA, were intermingled in all lesions. Production of 3 types of immunoglobulins may be caused by heavy-chain class switching, constantly occurring in certain proportions.

Animals↗
PubMed1992

Morphology of cerebral plaque-like lesions in hereditary cerebral hemorrhage with amyloidosis (Dutch).

We studied the presence and morphology of plaque-like lesions in the frontal cortex of six patients, aged 40 to 76 years, with hereditary cerebral hemorrhage with amyloidosis--Dutch type (HCHWA-D), using beta/A4 immuno-, silver, Congo red and thioflavin S staining. Two types of beta/A4 immunoreactive and Congo red-negative plaques were detected. The first type was composed of argyrophilic fibrous material in periodic acid-methenamine silver (PAM) and modified Bielschowsky staining and lacked silver-stained degenerating neurites. Therefore, this type of plaque has the same staining properties as the diffuse plaque described in Alzheimer's disease, Down's syndrome and nondemented elderly. The second type of plaque, occurring only in the three oldest patients and numerically increasing with age, consisted of a spherical non-argyrophilic area of granular texture with a rim of PAM-positive material. The PAM-positive fibrous material of both types of plaques was mingled with coarser and compact, irregular-shaped argyrophilic structures in the oldest patient. The described plaques did not show bright fluorescence with thioflavin S staining. These results indicate, that the morphology of plaques, encountered in HCHWA-D, is diverse and changes with age.

Adult↗
PubMed2005

Histochemical and topo-optical investigations on tissue-isolated and in vitro amyloid fibrils.

An improved microscopic slide preparation for staining of tissue-isolated and in vitro amyloid fibrils is described in detail. Specimens were prepared by slow drying of an amyloid fibril suspension on aminoalkyl-silanised glass slides underneath a coverglass. The purpose of this method is to obtain microscopically visible fibers. Polarization microscopy was performed on unstained fibers in different embedding media, on fibers stained with Congo red, toluidine blue, 1,9-dimethylmethylene blue, anisotropic PAS reaction and Sudan black. Results were identical in 8 tissue-isolated amyloid fibril preparations. The refractive index of amyloid was about 1.5, as expected for protein fibrils. Congo red-stained fibrils showed yellow or blue-green polarization colors, while staining with toluidine blue or 1,9-dimethylmethylene blue induced green or orange polarization colors. The latter dyes stained the fibrils even in buffers with low pH or high ionic strength, pointing to strong acidic groups like sulphates in amyloid. The anisotropic PAS reaction for selective demonstration of periodate reactive carbohydrates in tissue-isolated amyloid fibrils was positive. Thus, linearly ordered acidic groups and carbohydrate residues could be detected for the first time in tissue-isolated amyloid fibrils using an improved technique for microscopic slide preparation on one side and topo-optical reactions on the other.

Amyloid↗
PubMed2005

A case report of dystrophic localized amyloidosis that developed in the left thigh.

We report on a 50-year-old man with dystrophic localized amyloidosis who noticed a soft tumor in his left thigh about 20 years ago, after which the tumor has gradually enlarged. The multicystic tumor showed hemorrhage, hematoma, necrosis, fibrosis, and tiny nodules and various polymorphous granulomas were observed. One was rich in eosinophilic amorphous materials and cholesterol crystals, and was poor in cell reaction. Another was formed by granuloma consisting of multinucleated giant cells, foamy cells, and macrophages. Transitional granulomas between the two were also observed. The materials showed eosinophilia and red staining and apple-green birefringence in polarized light by alkaline Congo-red stain, and they were also resistant to potassium permanganate pretreatment. They were also positive for amyloid P component and consistently negative for amyloid A, kappa- and lambda-light chains, beta2-microglobulin, and transthyretin. Therefore, it was suggested that this might be an amyloid derived from the hematoma, which has not been reported to date.

Amyloid↗