Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMYLOIDOSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,279 records · Page 71Linked to original sources

Familial Mediterranean fever with amyloidosis associated with novel exon 2 mutation (S1791) of the MEFV gene.

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever, serositis, and a risk for AA amyloidosis. FMF is caused by mutations in the Mediterranean fever gene (MEFV), which is expressed in blood cells of the myelomonocytic differentiation pathway. We identified a novel mutation S1791 in exon 2 of MEFV in two members of a family of Turkish origin. In both cases, S1791 was in compound heterozygosity with MEFV mutation M694V, and the characteristic clinical syndrome of FMF including amyloidosis was found. The location of S1791 in exon 2 is of interest because (1) amyloidosis in FMF has previously been found to be strongly associated with compound exon 10 mutations and (2) it supports the notion that the mechanism causing FMF is connected to the cytoplasmic rather than nuclear function of the molecule.

Amyloidosis↗

Primary amyloidosis patients with significant organ dysfunction tolerate autologous transplantation after conditioning with single-dose total body irradiation alone: a feasibility study.

High-dose melphalan has been commonly used as conditioning for amyloidosis with considerable toxicity. We hypothesized that the novel conditioning regimen of 550 cGy total body irradiation (TBI) alone for autologous peripheral blood stem cell transplantation would have reduced organ toxicity and thus permit safer transplantation of primary amyloidosis patients, even those with poor risk disease. The comprehensive regimen included pretransplantation chemotherapy, single-dose TBI alone (550 cGy at 30 cGy/min) conditioning, and post-transplantation interferon-alpha maintenance. Thirteen patients were enrolled in this feasibility study. Patients with multiorgan involvement were included; 10 patients had poor or intermediate risk disease. Cardiac toxicity was significant. Treatment-related mortality through 100 days post-transplantation was 15% and was caused by cardiac mortality. One patient died from arrhythmia after receiving TBI; 2 patients had grade IV cardiac toxicity (with subsequent complete recovery). One patient died 1 month after mobilization from progressive cardiomyopathy and never received conditioning. However, noncardiac organ toxicity was mild. No patient required parenteral nutrition support; no patient developed mucositis; and no patient experienced gastrointestinal bleeding following transplantation. The complete hematologic remission rate was 45%, with pretransplantation chemotherapy being the most active part of the regimen. Survival estimates from enrollment to 1 and 2 years post-transplantation were 66% and 47%, respectively. Causes of death were disease progression (6), myelodysplasia (1), arrhythmia following TBI (1), and congestive heart failure after mobilization (1). In this cohort of primary amyloidosis patients, the transplantation regimen of 550 cGy TBI was feasible and associated with modest treatment-related mortality. Efficacy with TBI conditioning may be reduced compared with high-dose melphalan, but this should be explored in a future trial with a larger cohort of patients.

Adult↗

Amyloidosis: new strategies for treatment.

Amyloidosis is a disorder of protein folding in which normally soluble proteins are deposited extracellularly as insoluble fibrils, impairing tissue structure and function. Over 20 unrelated proteins form amyloid fibrils in vivo, with fibrils sharing a lamellar cross-beta sheet structure, composed of non-covalently associated protein or peptide subunits. Amyloidosis may be acquired or hereditary and local or systemic, and is defined according to the precursor protein. Of note, local amyloid deposition occurs in Alzheimer's disease (AD) and maturity onset diabetes but their precise role in the pathogenesis of these diseases remains uncertain. Glycosaminoglycans (GAG) and the pentraxin protein, serum amyloid P (SAP) component, are universal non-fibrillar constituents of amyloid deposits that contribute to fibrillogenesis. We review potential therapies for amyloidosis, which include measures to reduce the production of amyloidogenic precursor proteins, interference with fibrillogenesis, and enhancement of amyloid clearance, either by active or passive immunisation or by destabilising deposits through removal of serum amyloid P component.

Alzheimer Disease↗

Laryngeal amyloidosis.

Laryngeal amyloidosis is a rare disease. Surgery has been the mainstay of treatment either endoscopically or by an external neck approach. In more recent years, surgery with the carbon dioxide laser has been advocated for this condition. Four cases of laryngeal amyloidosis are presented. The application and the advantages of the carbon dioxide laser for the treatment of laryngeal amyloidosis are discussed.

Aged↗

Fatal massive upper respiratory tract haemorrhage: an unusual complication of localized amyloidosis of the larynx.

Localized amyloidosis of the larynx is usually described as a non-bleeding lesion. We report a patient with localized laryngeal amyloidosis who developed a massive upper respiratory tract haemorrhage and died. This potentially fatal complication of localized amyloidosis of the larynx merits recognition as the disease could be controlled in most instances by surgical excision of the amyloid deposit.

Adult↗

Familial systemic amyloidosis associated with bilateral sensorineural hearing loss and bilateral facial palsies.

The Finnish type of familial amyloid polyneuropathy due to variant gelsolin is a rare form of familial amyloidosis. The subtype was first described in 1969 and is characterized by progressive cranial neuropathies, corneal lattice dystrophy and distal sensorimotor dysfunction. It is extremely uncommon, with only two families known to be affected in the UK. We discuss the case of a 70-year-old woman who presented with bilateral facial nerve palsies, bilateral sensorineural hearing loss and Finnish type familial hereditary amyloidosis. A literature search of the Medline database (1966-2005) was performed, using the keywords 'amyloid', 'hearing loss' and 'facial palsy'; however, this association appears to be a novel finding. We review the current literature and discuss otorhinolaryngological presentations of amyloidosis.

Aged↗

Myopathy in primary systemic amyloidosis.

Involvement of the peripheral nervous system by amyloidosis is common. It is less well recognized that amyloid can directly infiltrate and weaken skeletal muscle. We report a case of a 73-year-old woman, known to have cardiac amyloidosis, who developed profound weakness secondary to amyloid myopathy. Review of the 8 other well documented cases in the literature has revealed a rather homogeneous syndrome. Proximal weakness, muscle stiffness, pseudohypertrophy and myalgia constitute the principal features. This syndrome usually develops in cases with well recognized generalized amyloidosis. Amyloid is deposited within the basal lamina of blood vessels and muscle fibers.

Aged↗

Hereditary transthyretin amyloidosis: molecular basis and therapeutical strategies.

Transthyretin (TTR) is a transport protein for thyroid hormones and vitamin A and might have an important role in the nervous system. However, TTR can undergo a conformational change and form amyloid fibrils, in both acquired and hereditary forms of systemic amyloidosis. More than 80 TTR mutations have been associated with autosomal dominant amyloidosis, usually presenting with peripheral and autonomic neuropathy and/or cardiomyopathy. Major areas of research in TTR amyloidosis include: molecular mechanisms leading to fibril formation; mechanisms of fibril-induced cell death; modulators of phenotypic expression of the disease; and therapeutic strategies.

Amyloid↗

Effect of nitric oxide in amyloid fibril formation on transthyretin-related amyloidosis.

Although oxidative stress is said to play an important role in the amyloid formation mechanism in several types of amyloidosis, few details about this role have been described. Amyloid is commonly deposited around the vessels that are the primary site of action of nitric oxide generated from endothelial cells and smooth muscle cells, so nitric oxide may be also implicated in amyloid formation. For this study, we examined the in vitro effect of S-nitrosylation on amyloid formation induced by wild-type transthyretin, a precursor protein of senile systemic amyloidosis, and amyloidogenic transthyretin V30M, a precursor protein of amyloid deposition in familial amyloidotic polyneuropathy. S-Nitrosylation of amyloidogenic transthyretin V30M via the cysteine at position 10 was 2 times more extensive than that of wild-type transthyretin in a nitric oxide-generating solution. Both wild-type transthyretin and amyloidogenic transthyretin V30M formed amyloid fibrils under acidic conditions, and S-nitrosylated transthyretins exhibited higher amyloidogenicity than did unmodified transthyretins. Moreover, S-nitrosylated amyloidogenic transthyretin V30M formed more fibrils than did S-nitrosylated wild-type transthyretin. Structural studies revealed that S-nitrosylation of amyloidogenic transthyretin V30M induced a change in its conformation, as well as instability of the tetramer conformation. These results suggest that the nitric oxide-mediated modification of transthyretin, especially variant transthyretin, may play an important role in amyloid formation in senile systemic amyloidosis and familial amyloidotic polyneuropathy.

Amino Acid Substitution↗

[Echocardiographic analysis in cardiac amyloidosis].

Systemic amyloidosis with cardiac involvement may clinically be suspected in the presence of heart failure or arrhythmia of unknown origin. Herein two cases of cardiac amyloidosis are described with a clinical presentation of heart failure refractory to usual treatment. The key role of echocardiography in the diagnosis and prognosis evaluation of cardiac amyloidosis is discussed. A treatment targeted against the generation of amyloid fibril should ideally be initiated before apparition of heart failure.

Aged↗

Bullous amyloidosis: the mechanism of blister formation revealed by electron microscopy.

BACKGROUND: Few electron microscopic studies of blister lesions in bullous amyloidosis have been reported, and the mechanism of blister formation remains to be elucidated. This study was designed to examine the nature of bullous amyloidosis ultrastructurally, and clarify the pathogenesis of blister formation. METHODS: We examined a 47-year-old woman with IgD-lambda type myeloma, suffering from bullous lesions on her hands and feet caused by trauma or rubbing. Light and electron microscopic studies were performed. RESULT: Ultrastructurally, amyloid deposits aggregated under the lamina densa. Keratinocyte protrusions penetrated the dermis through the gap in the lamina densa and enfolded amyloid deposits. Amyloid globules were found in enlarged intercellular spaces of keratinocytes. Desmosomes were sparsely distributed in some areas of the epidermis. CONCLUSION: These results indicate that keratinocytes enfold the amyloid globules and take them in the intercellular space of epidermis, and that the breakdown of the lamina densa and widening of the intercellular space between keratinocytes induce skin fragility. Trauma or rubbing of her hands and feet appears to act as the localized precipitating factor of blister formation in bullous amyloidosis.

Amyloid↗

Localized amyloidosis of the glans penis: a case report and literature review.

BACKGROUND: Primary localized cutaneous amyloidosis is an uncommon lesion with a varied pathogenesis. METHODS: We report the case of a 67-year-old-male discovered to have a localized amyloid lesion of the glans penis. RESULTS: Biopsy of the lesion revealed dermal deposits of amorphous eosinophilic material which stained positive with Congo red and amyloid P protein. Additional stains, including kappa and lambda light chains, amyloid A, and transthyretin, were negative. The lesion has remained asymptomatic, with no evidence of systemic disease identified, and no further treatment has been necessary. CONCLUSIONS: This is the sixth reported case of localized amyloidosis of the glans penis. Based on the clinical behavior and pathologic characteristics, this type of lesion is best classified as primary localized cutaneous amyloidosis, in the same family as the macular/lichenoid type lesions.

Aged↗

Primary (localised non-familial) conjunctival amyloidosis: three case reports.

Conjunctival amyloidosis is an uncommon condition which usually arises secondary to chronic infection or trauma to the eye. It is rare to find significant deposits of amyloid involving the conjunctiva alone in the absence of a known antecedent infective, traumatic or hereditofamilial disorder. We report three patients with primary localised conjunctival amyloidosis. Each patient presented with a painless swelling in the lower fornix; in two this gradually extended to involve the bulbar and palpebral conjunctiva of both eyes with friable yellow deposits. Detailed clinical photographs illustrate the specific features of the disease. None of the patients had previous ocular pathology and bacterial, viral and fungal cultures of the conjunctiva were negative. There were no signs of inflammation. Conjunctival biopsies in each case showed large amorphous nodular deposits of amyloid within the substantia propria. Extensive systemic investigations including serum and urinary protein immunoelectrophoresis were normal. Follow-up ranged from 2 to 15 years after presentation. Treatment was symptomatic. As the typical features of amyloidosis present late in the course of conjunctival disease a diagnostic biopsy is often delayed. Once there is histopathological verification plasma cell disease must be excluded, although if the amyloid is limited to the conjunctiva systemic involvement is unlikely.

Aged↗

Amyloid beta 2-microglobulin is modified with N epsilon-(carboxymethyl)lysine in dialysis-related amyloidosis.

Recent work from this laboratory revealed that advanced glycation end product was localized to amyloid deposits in patients with dialysis-related amyloidosis by immunohistochemistry using a monoclonal antibody to advanced glycation end product. To elucidate the epitope of the antibody, N alpha-p-tosyl-L-lysine-methyl ester was incubated with glucose in vitro, and then a compound reactive to the antibody was purified from the incubate by buthanol extraction, XAD-2 column chromatography, and high-performance liquid chromatography while the reactivity was examined by enzyme linked immunosorbent assay. The purified compound was identified as N epsilon-(carboxymethyl)-N alpha-p-tosyl-L-lysine-methyl ester by using secondary ion mass spectrometry, and 1H- and 13C-nuclear magnetic resonance spectroscopy. The epitope of the antibody was identified as -CH2-NH-CH2-COOH by enzyme-linked immunosorbent assay of compounds with structures similar to N epsilon-(carboxymethyl)lysine. Immunochemical study using the antibody demonstrated the presence of N epsilon-(carboxymethyl)lysine in the beta 2-microglobulin dimer (molecular weight 23929) isolated from the synovium amyloid of a hemodialysis patient with dialysis-related amyloidosis. In conclusion, amyloid beta 2-microglobulin is modified with N epsilon-(carboxymethyl)lysine in dialysis-related amyloidosis.

Amyloid↗

Two different types of amyloid deposits--apolipoprotein A-IV and transthyretin--in a patient with systemic amyloidosis.

Certain forms of systemic amyloidosis have been associated with the pathologic deposition as fibrils of three different apolipoprotein-related proteins--apolipoprotein A-I, apolipoprotein A-II, and serum amyloid A. We have previously reported (Bergström et al, Biochem Biophys Res Commun 2001;285:903-908) that amyloid fibrils extracted from the heart of an elderly male with senile systemic amyloidosis contained, in addition to wild-type transthyretin-related molecules, an N-terminal fragment of yet a fourth apolipoprotein--apolipoprotein A-IV (apoA-IV). We now provide the results of our studies that have established the complete amino-acid sequence of this approximately 70-residue component and, additionally, have shown this protein to be the product of an unmutated apoA-IV gene. Notably, the apoA-IV and transthyretin fibrils were not codeposited but, rather, had anatomically distinct patterns of distribution within the heart and other organs, as evidenced immunohistochemically, by variation in the ultra structural morphology and by differences in the intensity of Congo red birefringence. These findings provide the first conclusive evidence that two separate forms of amyloid, each derived from a wild-type amyloidogenic precursor protein, were present in a patient with systemic amyloidosis.

Aged↗

Amyloid and nonfibrillar deposits in mice transgenic for wild-type human transthyretin: a possible model for senile systemic amyloidosis.

The human serum protein transthyretin (TTR) is highly fibrillogenic in vitro and is the fibril precursor in both autosomal dominant (familial amyloidotic polyneuropathy [FAP] and familial amyloidotic cardiomyopathy [FAC]) and sporadic (senile systemic amyloidosis [SSA]) forms of human cardiac amyloidosis. We have produced mouse strains transgenic for either wild-type or mutant (TTRLeu55Pro) human TTR genes. Eighty-four percent of C57BI/6xDBA/2 mice older than 18 months, transgenic for the wild-type human TTR gene, develop TTR deposits that occur primarily in heart and kidney. In most of the animals, the deposits are nonfibrillar and non-Congophilic, but 20% of animals older than 18 months that bear the transgene have human TTR cardiac amyloid deposits identical to the lesions seen in SSA. Amino terminal amino acid sequence analysis and mass spectrometry of the major component extracted from amyloid and nonamyloid deposits revealed that both were intact human TTR monomers with no evidence of proteolysis or codeposition of murine TTR. This is the first instance in which the proteins from amyloid and nonfibrillar deposits in the same or syngeneic animals have been shown to be identical by sequence analysis. It is also the first time in any form of amyloidosis that nonfibrillar deposits have been shown to systematically occur temporally before the appearance of fibrils derived from the same precursor in the same tissues. These findings suggest, but do not prove, that the nonamyloid deposits represent a precursor of the fibril. The differences in the ultrastructure and binding properties of the deposits, despite the identical sizes and amino terminal amino acid sequences of the TTR and the dissociation of deposition and fibril formation, provide evidence that in vivo factors, perhaps associated with aging, impact on both systemic precursor deposition and amyloid fibril formation.

Aging↗

Gastrointestinal beta2microglobulin amyloidosis in hemodialysis patients: biochemical analysis of amyloid proteins in small formalin-fixed paraffin-embedded tissue specimens.

We present here a first report on the biochemical analysis of intestinal amyloid deposits found in two cases of hemodialysis-related amyloidosis. A new microtechnique was applied for extraction and immunochemical/chemical characterization of amyloid proteins in small amounts of fixed tissue, thus allowing precise identification of beta2microglobulin amyloid (Abeta2M) in both cases studied. The molecular mass of the identified amyloid beta2M was close to that of intact beta2M (12 kDa), with no evidence of the products of proteolytic fragmentation of these molecules. The isoelectrofocusing of the purified Abeta2M demonstrated a shift to more acidic pI as compared to the normal beta2M analyzed under the same experimental conditions. The obtained data suggest that the intestinal amyloid deposits in dialysis-related amyloidosis contain disease-specific beta2M isoforms, which could play a role in the pathogenesis of amyloid disease. The new methodology used might be useful in obtaining precise diagnosis of amyloidosis that is necessary for appropriate therapy, and also provide new important information on the chemical structure of amyloid proteins.

Aged↗

Gastrointestinal perforation early after peripheral blood stem cell transplantation for AL amyloidosis.

The morbidity and mortality of AL amyloidosis is caused by the deposition of Ig light chains as amyloid protein in vital organs. With conventional therapy median survival of patients with AL amyloidosis is 10-14 months. With high-dose chemotherapy clinical remissions of organ-specific disease have been reported. Here, we present a patient with high-risk AL amyloidosis who was given high-dose therapy and a peripheral blood stem cell transplant. Four days later she died of gastrointestinal perforation due to amyloid infiltrations.

Adult↗