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Sample records for amyloid polyneuropathy assessed

  1. Permanent dysphagia in familial amyloid polyneuropathy (ATTRVal30Met).

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    Monteiro, Cecília; Magalhães, Marina; Correia, Carlos; Taipa, Ricardo

    2012-06-01

    Gastrointestinal symptoms are frequent in familial amyloid polyneuropathy, mainly resulting from autonomic nervous system involvement. Dysphagia is one of the possible symptoms, although rarely severe or sudden. We describe a case of a sudden onset and severe dysphagia, a rare form of presentation, in a patient whose polyneuropathy was still beeing investigated and turned out to be ATTRVal30Met-polyneuropathy.

  2. Tafamidis for transthyretin familial amyloid polyneuropathy

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    Maia, Luis F.; Martins da Silva, Ana; Waddington Cruz, Marcia; Planté-Bordeneuve, Violaine; Lozeron, Pierre; Suhr, Ole B.; Campistol, Josep M.; Conceição, Isabel Maria; Schmidt, Hartmut H.-J.; Trigo, Pedro; Kelly, Jeffery W.; Labaudinière, Richard; Chan, Jason; Packman, Jeff; Wilson, Amy; Grogan, Donna R.

    2012-01-01

    Objectives: To evaluate the efficacy and safety of 18 months of tafamidis treatment in patients with early-stage V30M transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods: In this randomized, double-blind trial, patients received tafamidis 20 mg QD or placebo. Coprimary endpoints were the Neuropathy Impairment Score–Lower Limbs (NIS-LL) responder analysis (<2-point worsening) and treatment-group difference in the mean change from baseline in Norfolk Quality of Life–Diabetic Neuropathy total score (TQOL) in the intent-to-treat (ITT) population (n = 125). These endpoints were also evaluated in the efficacy-evaluable (EE; n = 87) population. Secondary endpoints, including changes in neurologic function, nutritional status, and TTR stabilization, were analyzed in the ITT population. Results: There was a higher-than-anticipated liver transplantation dropout rate. No differences were observed between the tafamidis and placebo groups for the coprimary endpoints, NIS-LL responder analysis (45.3% vs 29.5% responders; p = 0.068) and change in TQOL (2.0 vs 7.2; p = 0.116) in the ITT population. In the EE population, significantly more tafamidis patients than placebo patients were NIS-LL responders (60.0% vs 38.1%; p = 0.041), and tafamidis patients had better-preserved TQOL (0.1 vs 8.9; p = 0.045). Significant differences in most secondary endpoints favored tafamidis. TTR was stabilized in 98% of tafamidis and 0% of placebo patients (p < 0.0001). Adverse events were similar between groups. Conclusions: Although the coprimary endpoints were not met in the ITT population, tafamidis was associated with no trend toward more NIS-LL responders and a significant reduction in worsening of most neurologic variables, supporting the hypothesis that preventing TTR dissociation can delay peripheral neurologic impairment. Classification of evidence: This study provides Class II evidence that 20 mg tafamidis QD was associated with no difference in clinical progression in

  3. [Sequential heart and liver transplantation for familial amyloid polyneuropathy].

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    Lladó, Laura; Fabregat, Joan; Ramos, Emilio; Baliellas, Carme; Roca, Josep; Casasnovas, Carlos

    2014-03-04

    Combined heart and liver transplantation for familial amyloid polyneuropathy (FAP) is currently the best treatment for patients with cardiomyopathy related to FAP. However, its optimal timing and the possibility of domino liver transplantation in this setting remain under discussion. Most such cases in the medical literature have been performed simultaneously, although many of them have required the use of veno-venous bypass and the majority have not used the liver as a graft for domino liver transplantation. We report 3 cases of non-Val30Met mutation that underwent sequential heart and domino liver transplantation at our institution. We describe the 3 cases and the medical literature, with special attention to the reason for sequential heart and liver transplantation, the role of transient elastography in this setting, and the feasibility of domino liver transplantation. In our experience, combined heart and liver transplantation is a feasible but challenging procedure for patients with FAP. Performing the procedure sequentially rather than simultaneously seems safer and easier, both technically and hemodynamically. More importantly, such an approach allows the use of livers from FAP patients as grafts for domino liver transplantation. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  4. Discredited legacy: Stigma and familial amyloid polyneuropathy in Northwestern Portugal.

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    Mendes, Álvaro; Sousa, Liliana; Sequeiros, Jorge; Clarke, Angus

    2017-06-01

    Genetic inherited conditions may result in feelings of stigmatisation, mainly because of visible physical appearance and its transmissibility to offspring. This article reports accounts of stigmatisation from Portuguese patients affected by the inherited neurodegenerative disease, familial amyloid polyneuropathy (FAP), living in the largest cluster of patients worldwide. We draw on semi-structured interviews conducted with individuals at-risk or affected by FAP, recruited through the national patients' association, about their experiences of stigmatisation related to the illness. Findings highlight the influence of a discrediting social context in the enactment of stigma. FAP was described as a source of devaluation and social distance and was permeated by beliefs of contagion in the community, especially in the past. The multigenerational nature of the illness within small communities was felt as a source of rejection for courtship and of devalued reproductive worth. Decisions to have (potentially affected) children seemed to be a target of implicit negative judgment. Dealing with stigma entailed restraint in talking about FAP especially outside the family, resistance to being treated as different, and social withdrawal. Some participants referred to recent substantial improvements in their social acceptance and a reduction in the intensity of the stigmatisation to which they are subject. The pattern of stigma may have changed considerably within the past few decades, as medical information about the disease became more widespread, as new medications have been introduced and as clinical trials of other potential treatments have been established. Our findings report the social consequences of stigma towards this disease group and may help to understand how stigma is experienced in other heritable diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. First European consensus for diagnosis, management, and treatment of transthyretin familial amyloid polyneuropathy

    NARCIS (Netherlands)

    Adams, David; Suhr, Ole B.; Hund, Ernst; Obici, Laura; Tournev, Ivailo; Campistol, Josep M.; Slama, Michel S.; Hazenberg, Bouke P.; Coelho, Teresa

    Purpose of review Early and accurate diagnosis of transthyretin familial amyloid polyneuropathy (TTR-FAP) represents one of the major challenges faced by physicians when caring for patients with idiopathic progressive neuropathy. There is little consensus in diagnostic and management approaches

  6. First European consensus for diagnosis, management, and treatment of transthyretin familial amyloid polyneuropathy

    OpenAIRE

    Adams, David; Suhr, Ole B.; Hund, Ernst; Obici, Laura; Tournev, Ivailo; Campistol, Josep M.; Slama, Michel S.; Hazenberg, Bouke P.; Coelho, Teresa

    2016-01-01

    Purpose of review Early and accurate diagnosis of transthyretin familial amyloid polyneuropathy (TTR-FAP) represents one of the major challenges faced by physicians when caring for patients with idiopathic progressive neuropathy. There is little consensus in diagnostic and management approaches across Europe. Recent findings The low prevalence of TTR-FAP across Europe and the high variation in both genotype and phenotypic expression of the disease means that recognizing symptoms can be diffic...

  7. Polyneuropathies.

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    Sommer, Claudia; Geber, Christian; Young, Peter; Forst, Raimund; Birklein, Frank; Schoser, Benedikt

    2018-02-09

    Polyneuropathies (peripheral neuropathies) are the most common type of disorder of the peripheral nervous system in adults, and specifically in the elderly, with an estimated prevalence of 5-8%, depending on age. The options for treatment depend on the cause, which should therefore be identified as precisely as possible by an appropriate diagnostic evaluation. This review is based on the current guidelines and on large-scale cohort studies and randomized, controlled trials published from 2000 to 2017, with an emphasis on non-hereditary types of polyneuropathy, that were retrieved by a selective search in PubMed. Diabetes is the most common cause of polyneuropathy in Europe and North America. Alcohol-associated polyneuropathy has a prevalence of 22-66% among persons with chronic alcoholism. Because of the increasing prevalence of malignant disease and the use of new chemotherapeutic drugs, chemotherapy-induced neuropathies (CIN) have gained in clinical importance; their prevalence is often stated to be 30-40%, with high variation depending on the drug(s) and treatment regimen used. Polyneuropathy can also arise from genetic causes or as a consequence of vitamin deficiency or overdose, exposure to toxic substances and drugs, and a variety of immunological processes. About half of all cases of polyneu - ropathy are associated with pain. Neuropathic pain can be treated symptomatically with medication. Exercise, physiotherapy, and ergotherapy can also be beneficial, depending on the patient's symptoms and functional deficits. A timely diagnosis of the cause of polyneuropathy is a prerequisite for the initiation of appropriate specific treatment. Patients with severe neuropathy of unidentified cause should be referred to a specialized center for a thorough diagnostic evaluation.

  8. Single-centre experience on transthyretin familial amyloid polyneuropathy: case series and literature review.

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    Martens, Broes; De Pauw, Michel; De Bleecker, Jan L

    2018-03-09

    Familial amyloid polyneuropathy (FAP) is a most often length-dependent axonal neuropathy, often part of a multisystem disorder also affecting other organs, such as cardiac, gastrointestinal, genitourinary, renal, meningeal and eye tissue. It is most frequently the result of a mutation in the TTR gene, most commonly a p.Val50Met mutation. TTR-FAP is a rare autosomal dominant heritable disabling, heterogeneous disease in which early diagnosis is of pivotal importance when attempting treatment. This paper discusses the course of four Belgian FAP patients with different TTR mutations (p.Val48Met; p.Val52Ala; p.Ala59Val; p.Val50Met). We also review the diagnosis and differential diagnosis of TTR-FAP, diagnostic studies, follow-up, its current treatment and those in development, prognosis and the importance of genetic counseling. At first, TTR-FAP is often misdiagnosed as a chronic inflammatory demyelinating polyneuropathy or chronic idiopathic axonal polyneuropathy. Genetic testing is obligatory to confirm the diagnosis of TTR-FAP, except in familial cases. Biopsy samples are an asset in diagnosing TTR-FAP but can be falsely negative. At the moment, tafamidis meglumine is considered as first-line treatment in stage I neurological disease. Patients eligible for liver transplantation should be carefully selected when first-line therapy fails.

  9. Familial amyloid polyneuropathy (TTR ala 60) in north west Ireland: a clinical, genetic, and epidemiological study.

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    Reilly, M M; Staunton, H; Harding, A E

    1995-01-01

    A cluster of cases of familial amyloid polyneuropathy has been described in Donegal, north west Ireland. Two patients from this region have been shown to have the ala 60 mutation in the transthyretin gene. Three kindreds with this mutation have also been described in the United States. Genealogical and haplotype studies indicate that all known patients with this mutation are related and are descended from a founder in north west Ireland. There is evidence for reduced penetrance of this disorder. A population based study showed that 1.1% of the population in this area in north west Ireland carry the mutation. This has implications in terms of diagnosis, genetic counselling, and treatment in the future. PMID:7608709

  10. In vivo detection of nerve injury in familial amyloid polyneuropathy by magnetic resonance neurography.

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    Kollmer, Jennifer; Hund, Ernst; Hornung, Benjamin; Hegenbart, Ute; Schönland, Stefan O; Kimmich, Christoph; Kristen, Arnt V; Purrucker, Jan; Röcken, Christoph; Heiland, Sabine; Bendszus, Martin; Pham, Mirko

    2015-03-01

    Transthyretin familial amyloid polyneuropathy is a rare, autosomal-dominant inherited multisystem disorder usually manifesting with a rapidly progressive, axonal, distally-symmetric polyneuropathy. The detection of nerve injury by nerve conduction studies is limited, due to preferential involvement of small-fibres in early stages. We investigated whether lower limb nerve-injury can be detected, localized and quantified in vivo by high-resolution magnetic resonance neurography. We prospectively included 20 patients (12 male and eight female patients, mean age 47.9 years, range 26-66) with confirmed mutation in the transthyretin gene: 13 with symptomatic polyneuropathy and seven asymptomatic gene carriers. A large age- and sex-matched cohort of healthy volunteers served as controls (20 male and 20 female, mean age 48.1 years, range 30-73). All patients received detailed neurological and electrophysiological examinations and were scored using the Neuropathy Impairment Score-Lower Limbs, Neuropathy Deficit and Neuropathy Symptom Score. Magnetic resonance neurography (3 T) was performed with large longitudinal coverage from proximal thigh to ankle-level and separately for each leg (140 axial slices/leg) by using axial T2-weighted (repetition time/echo time = 5970/55 ms) and dual echo (repetition time 5210 ms, echo times 12 and 73 ms) turbo spin echo 2D sequences with spectral fat saturation. A 3D T2-weighted inversion-recovery sequence (repetition time/echo time 3000/202 ms) was acquired for imaging of the spinal nerves and lumbar plexus (50 axial slice reformations). Precise manual segmentation of the spinal/sciatic/tibial/common peroneal nerves was performed on each slice. Histogram-based normalization of nerve-voxel signal intensities was performed using the age- and sex-matched control group as normative reference. Nerve-voxels were subsequently classified as lesion-voxels if a threshold of >1.2 (normalized signal-intensity) was exceeded. At distal thigh level

  11. Potential Role of In Vivo Confocal Microscopy for Imaging Corneal Nerves in Transthyretin Familial Amyloid Polyneuropathy.

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    Rousseau, Antoine; Cauquil, Cecile; Dupas, Benedicte; Labbé, Antoine; Baudouin, Christophe; Barreau, Emmanuel; Théaudin, Marie; Lacroix, Catherine; Guiochon-Mantel, Anne; Benmalek, Anouar; Labetoulle, Marc; Adams, David

    2016-09-01

    Small fiber neuropathy (SFN) is an important feature of transthyretin familial amyloid polyneuropathy (TTR-FAP). A practical and objective method for the clinical evaluation of SFN is needed to improve the management of this disease. In vivo confocal microscopy (IVCM) of the corneal nerves, a rapid noninvasive technique, may be used as a surrogate marker of SFN. To determine the correlation of SFN with IVCM in patients with TTR-FAP. A prospective, single-center, cross-sectional controlled study was conducted at the French National Reference Center for TTR-FAP from June 1, 2013, to June 30, 2014. Fifteen patients with TTR-FAP underwent a complete neurologic examination, including Neuropathy Impairment Score of the Lower Limbs, hand grip strength, and evaluation of vegetative dysfunction, as well as electrophysiologic studies (nerve conduction and electrochemical skin conductance) and intraepidermal nerve fiber density quantification. Patients and 15 controls (matched for age and sex) underwent ophthalmologic assessments, including corneal esthesiometry and IVCM. Correlation of corneal nerve fiber length (CNFL) with the severity of SFN. Of the 15 patients enrolled in the study, 6 were women (40%); mean (SD) age was 54.4 [13.7] years. The CNFL was shorter in the patients than in controls (13.08 vs 17.57 mm/mm2; difference of 4.49 [95% CI, 0.72 to 8.27]; P = .02). The patients' CNFL correlated with the severity of both autonomic neuropathy assessed by the Compound Autonomic Dysfunction Test (rs = 0.66 [95% CI, 0.22 to 0.87]; P = .008) or electrochemical skin conductance (rs = 0.80 [95% CI, 0.50 to 0.93]; P < .001) and sensorimotor neuropathy assessed using the Neuropathy Impairment Score of the Lower Limbs (rs = -0.58 [95% CI, -0.84 to -0.11]; P = .02). Patients with altered sensory nerve action potentials and intraepidermal nerve fiber density had a shorter CNFL (P = .04 and P = .02, respectively). The CNFL could be measured in all

  12. Unwanted road to anaemia in transthyretin familial amyloid polyneuropathy may continue irrespective of tafamidis treatment.

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    Ikeda, Tokunori; Masuda, Teruaki; Ueda, Mitsuharu; Yamashita, Taro; Misumi, Yohei; Shinriki, Satoru; Ando, Yukio

    2018-01-01

    Background This retrospective longitudinal study was performed to determine whether tafamidis treatment leads to improvements in commonly used blood data for transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods Commonly used blood data (complete blood count [including a haemogram], total protein, albumin, blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, γ-glutamyl transpeptidase, total bilirubin [T-Bil], creatine kinase, choline esterase, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, estimated glomerular filtration rate [eGFR], serum amyloid A protein, TTR, haemoglobin A1c, free triiodothyronine [FT3] and free thyroxine [FT4]) were investigated in 33 TTR-FAP patients. These values included longitudinal data at three time points: six months before or after tafamidis treatment and one year after tafamidis treatment. Longitudinal changes in each blood item were examined using a linear mixed model, adjusting for age at starting tafamidis, sex, TTR-FAP stage and value before tafamidis treatment. Results Our results show elevated TTR concentrations after tafamidis treatment. In contrast, haemoglobin, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, mean platelet volume, platelet distribution width, T-Bil, eGFR, FT3 and FT4, gradually decreased through a reference range. There were no characteristic observations in any other items. TTR binds to thyroid hormone; therefore, FT3 and FT4 decreased in inverse proportion to increased TTR concentrations. Conclusion Unfortunately, progression to anaemia may occur regardless of tafamidis treatment. Because anaemia is sometimes present in TTR-FAP, attention should be paid to longitudinal changes in commonly used blood data, irrespective of tafamidis treatment.

  13. First European consensus for diagnosis, management, and treatment of transthyretin familial amyloid polyneuropathy

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    Adams, David; Suhr, Ole B.; Hund, Ernst; Obici, Laura; Tournev, Ivailo; Campistol, Josep M.; Slama, Michel S.; Hazenberg, Bouke P.; Coelho, Teresa

    2016-01-01

    Purpose of review Early and accurate diagnosis of transthyretin familial amyloid polyneuropathy (TTR-FAP) represents one of the major challenges faced by physicians when caring for patients with idiopathic progressive neuropathy. There is little consensus in diagnostic and management approaches across Europe. Recent findings The low prevalence of TTR-FAP across Europe and the high variation in both genotype and phenotypic expression of the disease means that recognizing symptoms can be difficult outside of a specialized diagnostic environment. The resulting delay in diagnosis and the possibility of misdiagnosis can misguide clinical decision-making and negatively impact subsequent treatment approaches and outcomes. Summary This review summarizes the findings from two meetings of the European Network for TTR-FAP (ATTReuNET). This is an emerging group comprising representatives from 10 European countries with expertise in the diagnosis and management of TTR-FAP, including nine National Reference Centres. The current review presents management strategies and a consensus on the gold standard for diagnosis of TTR-FAP as well as a structured approach to ongoing multidisciplinary care for the patient. Greater communication, not just between members of an individual patient's treatment team, but also between regional and national centres of expertise, is the key to the effective management of TTR-FAP. PMID:26734952

  14. The Val30Met familial amyloid polyneuropathy specific Rasch-built overall disability scale (FAP-RODS(©) ).

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    Pruppers, Mariëlle H J; Merkies, Ingemar S J; Faber, Catharina G; Da Silva, Ana M; Costa, Vanessa; Coelho, Teresa

    2015-09-01

    Familial amyloid polyneuropathy (FAP) is a chronic debilitating multi-organic disorder, mainly assessed using ordinal-based impairment measures. To date, no outcome measure at the activity and participation level has been constructed in FAP. The current study aimed to design an interval activity/participation scale for FAP through Rasch methodology. A preliminary FAP Rasch-built overall disability scale (pre-FAP-RODS) containing 146 activity/participation items was assessed twice (interval: 2-4 week; test-retest reliability) in 248 patients with Val30Met FAP examined in Porto, Portugal, of which 65.7% have received liver transplantation. An ordinal-based 24-item FAP-symptoms inventory questionnaire (FAP-SIQ) was also assessed (validity purposes). The pre-FAP-RODS and FAP-SIQ data were subjected to Rasch analyses. The pre-FAP-RODS did not meet model's expectations. On the basis of requirements such as misfit statistics, differential item functioning, and local dependency, items were systematically removed until a final 34-item FAP-RODS(©) was constructed fulfilling all Rasch requirements. Acceptable reliability/validity scores were demonstrated. In conclusion, the 34-item FAP-RODS(©) is a disease-specific interval measure suitable for detecting activity and participation restrictions in patients with FAP. The use of the FAP-RODS(©) is recommended for future international clinical trials in patients with Val30Met FAP determining its responsiveness and its cross-cultural validation. Its expansion to other forms of FAP should also be focus of future clinical studies. © 2015 Peripheral Nerve Society.

  15. Familial amyloid polyneuropathy: elaboration of a therapeutic patient education programme, "EdAmyl".

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    Théaudin, Marie; Cauquil, Cécile; Antonini, Teresa; Algalarrondo, Vincent; Labeyrie, Céline; Aycaguer, Sophie; Clément, Mireille; Kubezyk, Marie; Nonnez, Géraldine; Morier, Agnès; Bourges, Catherine; Darras, Amandine; Mouzat, Laurence; Adams, David

    2014-12-01

    Transthyretin-related amyloidosis (ATTR) is an autosomal dominant disease affecting the peripheral and autonomic nervous system, heart, eyes and kidneys. It is the most disabling hereditary polyneuropathy in adults. The French National Reference centre for this disease was accredited in 2005 with 10 lines of action. One of them is to inform and educate patients about their disease to improve their care and reduce morbidities. We thus decided to elaborate a therapeutic patient education (TPE) programme, starting with patients' needs assessment. A qualitative research study was conducted with one-to-one semi-structured interviews of selected individuals. Recorded interviews were analysed to identify the skills that patients need to acquire. A TPE programme was elaborated on the basis of these findings. Seven patients, one asymptomatic carrier and two healthy spouses were interviewed. Analysis of the interviews showed that interviewees had a good knowledge of the disease and its symptoms but they had difficulties explaining the disease mechanism and did not have an adequate knowledge of the available treatment options, although they knew that liver transplant might halt progression of the disease. ATTR amyloidosis appeared to have a major negative impact on the patient's physical and mental well-being. Patients feared loss of autonomy and having to require assistance from their relatives and spouses. All interviewees were keen to participate in a TPE programme. Based on this needs assessment, we identified seven skills that patients need to acquire and several pedagogical goals to be achieved during the education programme. An interdisciplinary team then elaborated a complete TPE programme. Elaboration of a TPE programme for ATTR amyloidosis required to obtain useful information from the patients themselves, and their relatives, concerning their perception of their disease. This needs' assessment constituted the basis for designing the first TPE programme, to our

  16. Diagnosis and management of transthyretin familial amyloid polyneuropathy in Japan: red-flag symptom clusters and treatment algorithm.

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    Sekijima, Yoshiki; Ueda, Mitsuharu; Koike, Haruki; Misawa, Sonoko; Ishii, Tomonori; Ando, Yukio

    2018-01-17

    Hereditary ATTR (ATTRm) amyloidosis (also called transthyretin-type familial amyloid polyneuropathy [ATTR-FAP]) is an autosomal-dominant, adult-onset, rare systemic disorder predominantly characterized by irreversible, progressive, and persistent peripheral nerve damage. TTR gene mutations (e.g. replacement of valine with methionine at position 30 [Val30Met (p.Val50Met)]) lead to destabilization and dissociation of TTR tetramers into variant TTR monomers, which form amyloid fibrils that deposit in peripheral nerves and various organs, giving rise to peripheral and autonomic neuropathy and several non-disease specific symptoms.Phenotypic and genetic variability and non-disease-specific symptoms often delay diagnosis and lead to misdiagnosis. Red-flag symptom clusters simplify diagnosis globally. However, in Japan, types of TTR variants, age of onset, penetrance, and clinical symptoms of Val30Met are more varied than in other countries. Hence, development of a Japan-specific red-flag symptom cluster is warranted. Presence of progressive peripheral sensory-motor polyneuropathy and ≥1 red-flag sign/symptom (e.g. family history, autonomic dysfunction, cardiac involvement, carpal tunnel syndrome, gastrointestinal disturbances, unexplained weight loss, and immunotherapy resistance) suggests ATTR-FAP. Outside of Japan, pharmacotherapeutic options are first-line therapy. However, because of positive outcomes (better life expectancy and higher survival rates) with living donor transplant in Japan, liver transplantation remains first-line treatment, necessitating a Japan-specific treatment algorithm.Herein, we present a consolidated review of the ATTR-FAP Val30Met landscape in Japan and summarize findings from a medical advisory board meeting held in Tokyo on 18th August 2016, at which a Japan-specific ATTR-FAP red-flag symptom cluster and treatment algorithm was developed. Beside liver transplantation, a TTR-stabilizing agent (e.g. tafamidis) is a treatment option. Early

  17. Cardiovascular magnetic resonance myocardial T1 mapping to detect and quantify cardiac involvement in familial amyloid polyneuropathy

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    Oda, Seitaro [Kumamoto University, Faculty of Life Sciences, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Utsunomiya, Daisuke; Nakaura, Takeshi; Yuki, Hideaki; Kidoh, Masafumi; Hirata, Kenichiro; Taguchi, Narumi; Tsuda, Noriko; Shiraishi, Shinya; Namimoto, Tomohiro; Yamashita, Yasuyuki [Kumamoto University, Faculty of Life Sciences, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Morita, Kosuke [Kumamoto University Hospital, Department of Central Radiology, Kumamoto (Japan); Hirakawa, Kyoko; Takashio, Seiji; Izumiya, Yasuhiro; Yamamuro, Megumi; Hokimoto, Seiji; Tsujita, Kenichi [Kumamoto University, Faculty of Life Sciences, Department of Cardiology, Kumamoto (Japan); Ueda, Mitsuharu; Yamashita, Taro; Ando, Yukio [Kumamoto University, Faculty of Life Sciences, Department of Neurology, Kumamoto (Japan)

    2017-11-15

    This study sought to explore the potential role of non-contrast T1 mapping for the detection and quantification of cardiac involvement in familial amyloid polyneuropathy (FAP). Japanese patients with FAP [n = 41, age 53.2 ± 13.9 years, genotype Val30Met (n = 25), non-Val30Met (n = 16)] underwent cardiac magnetic resonance imaging that included T1 mapping (saturation-recovery method) and late gadolinium-enhanced (LGE) imaging on a 3.0-T MR scanner. Their native T1 was measured on mid-ventricular short-axis images and compared with 30 controls. Of the 41 FAP patients 29 were LGE positive. The native T1 was significantly higher in FAP patients than in the controls (1,634.1 ± 126.3 ms vs. 1,432.4 ± 69.0 ms, p < 0.01), significantly higher in LGE-positive- than LGE-negative FAP patients (1,687.1 ± 104.4 ms vs. 1,505.4 ± 68.5 ms, p < 0.01), and significantly higher in LGE-negative FAP patients than the controls (p < 0.01). A native T1 cutoff value of 1,610 ms yielded 85.4% accuracy for identifying LGE-positive FAP. The native T1 significantly correlated with the interventricular septum wall thickness, the left ventricular mass, the LGE volume, the plasma B-type natriuretic peptide level, and the E/e{sup '} ratio (all p < 0.01). T1 mapping is of high diagnostic accuracy for the detection of LGE-positive FAP. The native myocardial T1 may be correlated with the severity of cardiac amyloid deposition. (orig.)

  18. Curcumin could reduce the monomer of TTR with Tyr114Cys mutation via autophagy in cell model of familial amyloid polyneuropathy

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    Li H

    2014-10-01

    Full Text Available Hui Li,1,* Yu Zhang,1,* Li Cao,1 Ran Xiong,1 Bei Zhang,1 Li Wu,1 Zongbo Zhao,1 Sheng-Di Chen1,2 1Department of Neurology and Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 2Key Laboratory of Stem Cell Biology and Laboratory of Neurodegenerative Diseases, Institute of Health Science, Shanghai Institutes of Biological Sciences, Chinese Academy of Science, and Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Transthyretin (TTR familial amyloid polyneuropathy (FAP is an autosomal ­dominant inherited neurodegenerative disorder caused by various mutations in the transthyretin gene. We aimed to identify the mechanisms underlying TTR FAP with Tyr114Cys (Y114C mutation. Our study showed that TTR Y114C mutation led to an increase in monomeric TTR and impaired autophagy. Treatment with curcumin resulted in a significant decrease of monomeric TTR by recovering autophagy. Our research suggests that impairment of autophagy might be involved in the pathogenesis of TTR FAP with Y114C mutation, and curcumin might be a potential therapeutic approach for TTR FAP. Keywords: curcumin, familial amyloid polyneuropathy, transthyretin, autophagy

  19. Involvement of Macrophages in the Pathogenesis of Familial Amyloid Polyneuropathy and Efficacy of Human iPS Cell-Derived Macrophages in Its Treatment.

    Directory of Open Access Journals (Sweden)

    Genki Suenaga

    Full Text Available We hypothesized that tissue-resident macrophages in familial amyloid polyneuropathy (FAP patients will exhibit qualitative or quantitative abnormalities, that may accelerate transthyretin (TTR-derived amyloid deposition. To evaluate this, we examined the number and subset of tissue-resident macrophages in heart tissue from amyloid-deposited FAP and control patients. In both FAP and control patients, tissue-resident macrophages in heart tissue were all Iba+/CD163+/CD206+ macrophages. However, the number of macrophages was significantly decreased in FAP patients compared with control patients. Furthermore, the proportion of intracellular TTR in CD14+ monocytes was reduced in peripheral blood compared with healthy donors. Based on these results, we next examined degradation and endocytosis of TTR in human induced pluripotent stem (iPS cell-derived myeloid lineage cells (MLs, which function like macrophages. iPS-MLs express CD163 and CD206, and belong to the inhibitory macrophage category. In addition, iPS-MLs degrade both native and aggregated TTR in a cell-dependent manner in vitro. Further, iPS-MLs endocytose aggregated, and especially polymerized, TTR. These results suggest that decreased tissue-localized macrophages disrupt clearance of TTR-derived amyloid deposits, leading to progression of a pathological condition in FAP patients. To improve this situation, clinical application of pluripotent stem cell-derived MLs may be useful as an approach for FAP therapy.

  20. Graded assessment and classification of impaired temperature sensibility in patients with diabetic polyneuropathy.

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    Hansson, P; Lindblom, U; Lindström, P

    1991-01-01

    Thermal sensibility was quantitatively assessed in the feet of 46 diabetic patients. In subjects with sensibility deficits the perception threshold for warmth or cold, or of heat pain, was either increased or lost. Four stages of impaired thermal sensibility were defined, and a classification of dysfunction is proposed which could be useful in routine clinical examination of patients with diabetic polyneuropathy. The classification of impaired thermal sensibility correlated significantly with the results of a bedside screening examination aimed at describing the severity of the polyneuropathy in terms of its regional extent. PMID:1880516

  1. Comparison between (99m)Tc-diphosphonate imaging and MRI with late gadolinium enhancement in evaluating cardiac involvement in patients with transthyretin familial amyloid polyneuropathy.

    Science.gov (United States)

    Minutoli, Fabio; Di Bella, Gianluca; Mazzeo, Anna; Donato, Rocco; Russo, Massimo; Scribano, Emanuele; Baldari, Sergio

    2013-03-01

    Cardiac involvement is not rare in systemic amyloidosis and is associated with poor prognosis. Both (99m)Tc-diphosphonate imaging and cardiac MRI with late gadolinium enhancement are considered valuable tools in revealing amyloid deposition in the myocardium; however, to our knowledge, no comparative study between the two techniques exists. We compared findings of these two techniques in patients with transthyretin-familial amyloid polyneuropathy (FAP). Eighteen patients with transthyretin-FAP underwent (99m)Tc-diphosphonate imaging and MRI with late gadolinium enhancement. Images were visually evaluated by independent readers to determine the presence of radiotracer accumulation or late gadolinium enhancement-positive areas at the level of cardiac chambers. Interobserver agreement ranged from moderate to very good for (99m)Tc-diphosphonate imaging findings and was very good for findings of MRI with late gadolinium enhancement. Left ventricle (LV) radiotracer uptake was found in 10 of 18 patients, whereas LV late gadolinium enhancement-positive areas were found in eight of 18 patients (χ(2) = 0.9; p = 0.343). One hundred fifty-nine LV segments showed (99m)Tc-diphosphonate accumulation, and 57 LV segments were late gadolinium enhancement positive (p < 0.0001). Radiotracer uptake was found in the right ventricle (RV) in eight patients and in both atria in five patients, whereas MRI showed that RV was involved in three patients and both atria in six patients; the differences were not statistically significant (RV, p = 0.07; atria, p = 1). Intermodality agreement between (99m)Tc-diphosphonate imaging and MRI ranged from fair to good. Our study shows that, although (99m)Tc-diphosphonate imaging and MRI with late gadolinium enhancement have similar capabilities to identify patients with myocardial amyloid deposition, cardiac amyloid infiltration burden can be significantly underestimated by visual analysis of MRI with late gadolinium enhancement compared with (99m

  2. Sixty years of transthyretin familial amyloid polyneuropathy (TTR-FAP) in Europe: where are we now? A European network approach to defining the epidemiology and management patterns for TTR-FAP

    Science.gov (United States)

    Parman, Yesim; Adams, David; Obici, Laura; Galán, Lucía; Guergueltcheva, Velina; Suhr, Ole B.; Coelho, Teresa

    2016-01-01

    Purpose of review Transthyretin familial amyloid polyneuropathy (TTR-FAP) is a highly disabling, life-threatening disease characterized by progressive sensorimotor and autonomic neuropathy. The profile of the disease across Europe is inadequately understood at present. Recent findings The incidence and clinical presentation of TTR-FAP varies widely within Europe, with early and late-onset disease subtypes. In those regions in which the disease is endemic (Portugal, Sweden, Cyprus, and Majorca), a Val30Met substitution in the TTR gene is the predominant genetic cause, whereas in the rest of Europe, cases of TTR-FAP are mainly sporadic with genetic heterogeneity. Current management strategies lack cohesion and patients can experience years of misdiagnosis and suboptimal treatment. Summary The article aims to disseminate the findings and recommendations from two recent meetings of the European Network for TTR-FAP (ATTReuNET), a panel comprising representatives from 10 European countries (Bulgaria, Cyprus, France, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, and Turkey) with expertise in the diagnosis and management of TTR-FAP. We explore the epidemiology and genetic mark of TTR-FAP across Europe and assess current management strategies, with a view to developing an alternative framework – a networked approach to disease management with an emphasis on collaboration and sharing of best practice. PMID:26734951

  3. Sensory nerve degeneration in a mouse model mimicking early manifestations of familial amyloid polyneuropathy due to transthyretin Ala97Ser.

    Science.gov (United States)

    Kan, H-W; Chiang, H; Lin, W-M; Yu, I-S; Lin, S-W; Hsieh, S-T

    2018-02-08

    Sensory nerve degeneration and consequent abnormal sensations are the earliest and most prevalent manifestations of familial amyloid polyneuropathy (FAP) due to amyloidogenic transthyretin (TTR). FAP is a relentlessly progressive degenerative disease of the peripheral nervous system. However, there is a lack of mouse models to replicate the early neuropathic manifestations of FAP. We established human TTR knock-in mice by replacing one allele of the mouse Ttr locus with human wild-type TTR (hTTR wt ) or human TTR with the A97S mutation (hTTR A97S ). Given the late onset of neuropathic manifestations in A97S-FAP, we investigated nerve pathology, physiology, and behavioural tests in these mice at two age points: the adult group (8 - 56 weeks) and the ageing group (> 104 weeks). In the adult group, nerve profiles, neurophysiology and behaviour were similar between hTTR wt and hTTR A97S mice. By contrast, ageing hTTR A97S mice showed small fibre neuropathy with decreased intraepidermal nerve fibre density and behavioural signs of mechanical allodynia. Furthermore, significant reductions in sural nerve myelinated nerve fibre density and sensory nerve action potential amplitudes in these mice indicated degeneration of large sensory fibres. The unaffected motor nerve physiology replicated the early symptoms of FAP patients, that is, sensory nerves were more vulnerable to mutant TTR than motor nerves. These results demonstrate that the hTTR A97S mouse model develops sensory nerve pathology and corresponding physiology mimicking A97S-FAP and provides a platform to develop new therapies for the early stage of A97S-FAP. © 2018 British Neuropathological Society.

  4. [Polyneuropathy in the elderly].

    Science.gov (United States)

    Löscher, Wolfgang; Iglseder, Bernhard

    2017-06-01

    The peripheral nervous system is subject to changes during the ageing process, e. g. deep tendon reflexes decrease, as does proprioception. Polyneuropathies, on the other hand, need to be distinguished from age-related changes as independent diseases with etiologies similar to those at younger ages. Etiologies includes metabolic disorders, primary inflammatory polyneuropathies, and systemic disorders. Neuropathies associated with diabetes, malignancy, and monoclonal gammopathies appear to be more common in older patients. Using a systematic approach, it is possible to establish a specific diagnosis in the majority of cases. Since polyneuropathies contribute to reduced mobility in the elderly, an assessment of functional skills is mandatory. Polyneuropathy therapy is primarily based on the treatment of underlying conditions and neuropathic pain management. Physiotherapy and rehabilitation target pain relief and maintaining activities of daily living.

  5. Methods for assessing diabetic polyneuropathy : validity and reproducibility of the measurement of sensory symptom severity and nerve function tests

    NARCIS (Netherlands)

    Valk, G D; Grootenhuis, P A; van Eijk, J T; Bouter, L M; Bertelsmann, F W

    The usefulness of sensory symptoms in the assessment of diabetic polyneuropathy is unclear. In the present study, we studied the hypothesis that pain is associated with small nerve fibre function, and that sensory alteration is associated with large nerve fibre function. In addition, we assessed the

  6. Methods for assessing diabetic polyneuropathy: validity and reproducibility of the measurement of sensory symptom severity and nerve function tests.

    NARCIS (Netherlands)

    Valk, G.D.; Grootenhuis, P.A.; van Eijk, J.T.M.; Bouter, L.M.; Bertelsmann, F.W.

    2000-01-01

    The usefulness of sensory symptoms in the assessment of diabetic polyneuropathy is unclear. In the present study, we studied the hypothesis that pain is associated with small nerve fibre function, and that sensory alteration is associated with large nerve fibre function. In addition, we assessed the

  7. Drug therapy for chronic idiopathic axonal polyneuropathy

    NARCIS (Netherlands)

    Vrancken, A. F. J. E.; van Schaik, I. N.; Hughes, R. A. C.; Notermans, N. C.

    2004-01-01

    BACKGROUND: Chronic idiopathic axonal polyneuropathy is an insidiously progressive sensory or sensorimotor polyneuropathy that affects elderly people. Although severe disability or handicap does not occur, it reduces quality of life. OBJECTIVES: To assess whether drug therapy for chronic idiopathic

  8. Diagnóstico de polineuropatía amiloidótica familiar tipo I en la Argentina Diagnosis of familial amyloid polyneuropathy type I in Argentina

    Directory of Open Access Journals (Sweden)

    Gladys Pérez

    2008-08-01

    transthyretin (TTR the principal component of amyloid fibrils. TTR is a normal plasma protein (previously called prealbumin that functions as a transport protein binding tiroxine and retinol. Among many mutations that have been found in the TTR gene, the variant with a single amino acid substitution of methionine for valine at position 30 (TTR Val30Met is the responsible of the Portuguese-type Familial Amyloidotic Polyneuropathy (FAP Type I. Interest in this pathology has arisen in Argentina because of the finding of an endemic area where a group of Portuguese immigrant families is localized. Since liver transplantation is a widely accepted treatment because it results in the disappearance of variant transthyretin from plasma, an early detection of the altered gene is essential. Thus, the objective of the present work was to optimize a methodology to detect the Val30Met mutation introducing modifications into techniques that were previously developed. The simple method here described is useful to confirm the diagnosis of the potential disease and, therefore, make it possible for patients to gain access to early liver transplantation.

  9. Validity of the shuttle walk test as a functional assessment of walking ability in individuals with polyneuropathy.

    Science.gov (United States)

    Erdmann, Peter G; Teunissen, Laurien L; van den Berg, Leonard H; Notermans, Nicolette C; Schröder, Carin D; Bongers, Bart C; van Meeteren, Nico L U

    2017-10-01

    This study assessed the validity of the shuttle walk test (SWT) to evaluate walking ability in patients with polyneuropathy. Forty-one patients with chronic idiopathic axonal polyneuropathy (CIAP) and 49 patients with multifocal motor neuropathy (MMN) performed both the 10-meter walk test (10MWT) and the SWT. Face validity was assessed by evaluating whether patients considered both tests to reflect their walking ability (Likert scale: 1 = not at all, 10 = very well). Concurrent validity was determined by Spearman rank-correlation analyses performed on the outcomes of both tests. Mean (SD) scores for how well the 10MWT and SWT reflected daily walking ability were 6.8 (1.3) and 7.4 (1.6) (p = 0.117) in patients with CIAP and 6.9 (1.2) and 7.9 (1.0) (p = 0.001) in patients with MMN, respectively. Correlation scores between both tests ranged from -0.70 to -0.82, except for 18 patients with MMN with a "normal" walking speed at the 10MWT (-0.21). The SWT seems a valid instrument for assessing walking ability in individuals with CIAP and MMN. Moreover, the SWT seems to be useful for investigating the symptoms elicited by walking long distances and may be more sensitive to changes when compared to the 10MWT. Implications for Rehabilitation Patients with polyneuropathy mainly experience problems when walking long distances. The 10-meter walk test does not possess sufficient psychometrics to diagnose walking abilities in these circumstances. The shuttle walk test is a valid instrument for assessing walking ability in individuals with polyneuropathy and might be the preferred instrument of choice when compared to the 10-meter walk test.

  10. Assessment of somatosensory indicators of polyneuropathy in patients with eating disorders.

    Science.gov (United States)

    Pauls, A M; Lautenbacher, S; Strian, F; Pirke, K M; Krieg, J C

    1991-01-01

    The somatosensory functions of small-diameter nerve fibres were tested on the lower and upper extremities in nine patients with anorexia nervosa, ten patients with bulimia nervosa and ten control subjects, by analysing warmth, cold, and pain thresholds. To test large-diameter nerve fibres, the vibration threshold was also measured. Both patient groups had markedly elevated pain thresholds compared with the control subjects. In contrast, warmth and cold thresholds were only suggestively elevated while vibration thresholds were not at all increased in the patients. A distal-proximal pattern of somatosensory deficits, suggestive of peripheral polyneuropathy, was not observed. Hence, a peripheral polyneuropathy affecting small or large afferent fibres as a consequence of an eating disorder seems to be a rare event.

  11. Concordance Between Different Amyloid Immunoassays and Visual Amyloid Positron Emission Tomographic Assessment.

    Science.gov (United States)

    Janelidze, Shorena; Pannee, Josef; Mikulskis, Alvydas; Chiao, Ping; Zetterberg, Henrik; Blennow, Kaj; Hansson, Oskar

    2017-12-01

    Visual assessment of amyloid positron emission tomographic (PET) images has been approved by regulatory authorities for clinical use. Several immunoassays have been developed to measure β-amyloid (Aβ) 42 in cerebrospinal fluid (CSF). The agreement between CSF Aβ42 measures from different immunoassays and visual PET readings may influence the use of CSF biomarkers and/or amyloid PET assessment in clinical practice and trials. To determine the concordance between CSF Aβ42 levels measured using 5 different immunoassays and visual amyloid PET analysis. The study included 262 patients with mild cognitive impairment or subjective cognitive decline from the Swedish BioFINDER (Biomarkers for Identifying Neurodegenerative Disorders Early and Reliably) cohort (recruited from September 1, 2010, through December 31, 2014) who had undergone flutemetamol F 18 ([18F]flutemetamol)-labeled PET. Levels of CSF Aβ42 were analyzed using the classic INNOTEST and the newer modified INNOTEST, fully automated Lumipulse (FL), EUROIMMUN (EI), and Meso Scale Discovery (MSD) assays. Concentrations of CSF Aβ were assessed using an antibody-independent mass spectrometry-based reference measurement procedure. The concordance of CSF Aβ42 levels and Aβ42:Aβ40 and Aβ42:tau ratios with visual [18F]flutemetamol PET status. Of 262 participants (mean [SD] age, 70.9 [5.5] years), 108 were women (41.2%) and 154 were men (58.8%). The mass spectrometry-derived Aβ42 values showed higher correlations with the modified Aβ42-INNOTEST (r = 0.97), Aβ42-FL (r = 0.93), Aβ42-EI (r = 0.93), and Aβ42-MSD (r = 0.95) assays compared with the classic Aβ42-INNOTEST assay (r = 0.88; P ≤ .01). The signal in the classic Aβ42-INNOTEST assay was partly quenched by recombinant Aβ1-40 peptide. However, the classic Aβ42-INNOTEST assay showed better concordance with visual [18F]flutemetamol PET status (area under the receiver operating characteristic curve [AUC], 0.92) compared with the

  12. Chronic inflammatory demyelinative polyneuropathy

    DEFF Research Database (Denmark)

    Said, Gérard; Krarup, Christian

    2013-01-01

    Chronic inflammatory demyelinative polyneuropathy (CIDP) is an acquired polyneuropathy presumably of immunological origin. It is characterized by a progressive or a relapsing course with predominant motor deficit. The diagnosis rests on the association of non-length-dependent predominantly motor ...

  13. Statins and polyneuropathy revisited

    DEFF Research Database (Denmark)

    Svendsen, Toke de Koning; Hansen, Peter Nørregaard; García-Rodríguez, Luis Alberto

    2017-01-01

    "); current use was further classified into long-term use (5+ years) and high or low intensity use. We used conditional logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs) to examine associations between polyneuropathy and statin use. RESULTS: We included 370 validated cases...... and 7400 controls. Ever use of statins was not associated with elevated risk of polyneuropathy (OR: 1.14, 95%CI: 0.84-1.54). Similarly, we found no associations between polyneuropathy risk and current use (OR: 1.11, 95% CI: 0.79-1.53), long-term use (OR: 1.13, 95%CI: 0.66-1.92), or high intensity statin......AIM: In a previous study, we found a positive association between statin use and polyneuropathy risk. Other studies reported equivocal results. The present study aimed to confirm our findings with a design similar to our previous study, but with a larger data set. METHODS: We searched medical...

  14. Organophosphate induced delayed polyneuropathy.

    Science.gov (United States)

    Qureshi, Asif; Ali, Rajab; Yaqoob, M Yousuf; Saleem, Omema

    2007-07-01

    Organophosphate induced delayed polyneuropathy (OPIDP) is a rare sensory-motor distal axonopathy, which usually occur after ingestion of large doses of certain organophosphate insecticide. The clinical picture is characterized by the distal paresis in lower limb associated with sensory symptoms. Electrodiagnostic studies show a motor axonal neuropathy. This case occurred in a 14 years old girl who developed cramping pain in both calves associated with lower limbs paresis 6 weeks after accidental organophosphate poisoning. After another week, she also developed weakness in both hands. Electrophysiological study was characterized by an axonal polyneuropathy pattern. Patient improved upon oral multivitamin therapy and physiotherapy.

  15. Critical care polyneuropathy in burn injuries: An integrative review.

    Science.gov (United States)

    Mc Kittrick, A; Kornhaber, R; Harats, M; Cleary, M; Visentin, D C; Haik, J

    2017-12-01

    Polyneuropathy is a debilitating condition which may be associated with large burns. The aim of this integrative review is to identify factors that contribute to the development of critical care polyneuropathy in patients admitted to an intensive care unit with a severe burn injury. PubMed, Scopus, CINHAL and EMBASE were searched up until July 2016. Studies/case reports focusing on critical care polyneuropathy for burn injured patients were included. The ten studies, included a total of 2755 burns subjects and identified 128 critical care polyneuropathy patients with an incidence of 4.4%. Three case reports identified prolonged ventilation and development of critical care neuropathy. Overall, factors identified as contributing to the development of critical care polyneuropathy in burn injured patients included prolonged ventilation (>7 days), large and deep total body surface area burns (mean TBSA 40%), and sepsis. Critical care polyneuropathy in burn patients remains challenging to diagnose and treat. To date, there is a lack of long term studies describing the impact of critical care polyneuropathy on functional performance or participation in activities of daily living in the burns population and this is consistent with the general literature addressing the lack of follow up assessments and long term consequences of persistent muscle weakness. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  16. Assessment of diabetic polyneuropathy in Zanzibar: Comparison between traditional methods and an automated point-of-care nerve conduction device

    Directory of Open Access Journals (Sweden)

    Elinor C. Vogt

    2017-12-01

    Full Text Available Aim: Scant information is available about the prevalence of diabetic polyneuropathy, as well as the applicability of screening tools in sub-Saharan Africa. We aimed to investigate these issues in Zanzibar (Tanzania. Methods: One hundred consecutive diabetes patients were included from the diabetes clinic at Mnazi Mmoja Hospital. Clinical characteristics were recorded. Further, we investigated: a self-reported numbness of the lower limbs, b ten-point monofilament test, c the Sibbald 60-s Tool and d nerve conduction studies (NCS, using an automated handheld point-of-care device, the NC-stat DPNCheck. Results: Mean age was 54 years, 90% had type 2 diabetes, and with 9 year average disease duration. Mean HbA1c was 8.5% (69 mmol/mol, blood pressure 155/88 mmHg. Sixty-two% reported numbness, 61% had positive monofilament and 79% positive Sibbald tool. NCS defined neuropathy in 45% of the patients. Only the monofilament showed appreciable concordance with the NCS, Cohen’s κ 0.43. Conclusions: The patient population was characterised by poor glycaemic control and hypertension. In line with this, neuropathy was rampant. The monofilament test tended to define more cases of probable neuropathy than the NCS, however specificity was rather low. Plantar skin thickening may have led to false positives in this population. Overall concordance was, however, appreciable, and could support continued use of monofilament as a neuropathy screening tool. The NC-stat DPNCheck could be useful in cases of diagnostic uncertainty or for research purposes in a low resource setting. Keywords: Diabetes mellitus, Sub-Saharan Africa, Diabetic polyneuropathy (DPN, Nerve conduction studies, NC-stat DPNCheck

  17. A routine PET/CT protocol with simple calculations for assessing cardiac amyloid using 18F-Florbetapir

    Directory of Open Access Journals (Sweden)

    Dustin Ryan Osborne

    2015-05-01

    Full Text Available Introduction: Cardiac amyloidosis is a rare condition characterized by the deposition of well-structured protein fibrils, proteoglycans, and serum proteins as amyloid. Recent work has shown that it may be possible to use 18F-Florbetapir to image cardiac amyloidosis. Current methods for assessment include invasive biopsy techniques. This work enhances foundational work by Dorbala et al. by developing a routine imaging and analysis protocol using 18F-Florbetapir for cardiac amyloid assessment.Methods: Ten patients, 3 healthy controls and 7 amyloid positive patients, were imaged using 18F-Florbetapir to assess cardiac amyloid burden. Four of the patients also were imaged using 82Rb-Chloride to evaluate possible 18F-Florbetapir retention because of reduced myocardial blood flow. Quantitative methods using modeling, SUVs and SUV ratios were used to define a new streamlined clinical imaging protocol that could be used routinely and provide patient stratification.Results: Quantitative analysis of 18F-Florbetapir cardiac amyloid data were compiled from a 20 minute listmode protocol with data histogrammed into two static images at 0-5 minutes and, 10-15 min or 15-20 min. Data analysis indicated the use of SUVs or ratios of SUVs calculated from regions draw in the septal wall were adequate in identification of all healthy controls from amyloid positive patients in this small cohort. Additionally, we found that it may be possible to use this method to differentiate patients suffering from AL vs. TTR amyloid.Conclusions: This work builds on the seminal work by Dorbala et Al. by describing a short 18F-Florbetapir imaging protocol that is suitable for routine clinical use and uses a simple method for quantitative analysis of cardiac amyloid disease.

  18. Sensorimotor polyneuropathy after hexavalent vaccination.

    Science.gov (United States)

    Gorczyca, Daiva; Schwirten, Ulrike

    2014-01-01

    New vaccines in infants are generally well tolerated and serious adverse events are rare. We present a patient who developed severe sensorimotor polyneuropathy 2 weeks after the first immunization with hexavalent routine vaccine (INFANRIX hexa). Through intense physiotherapy the infant made a complete recovery.

  19. Assessment of the nature interactions of β-amyloid protein by a nanoprobe method.

    Science.gov (United States)

    Caballero, Leonardo; Mena, Juan; Morales-Alvarez, Aurora; Kogan, Marcelo J; Melo, Francisco

    2015-01-01

    We present a method based on atomic force microscopy (AFM) to assess the work of adhesion between the interfaces of gold AFM tips functionalized with three peptides derived from β-sheet breaker LPFFD [CLPFFD-NH2 (i0) and their isomers CDLPFF-NH2 (i1) and CLPDFF-NH2 (i2)], and the beta-amyloid protein (Aβ1-42). β-Amyloid protein was deposited onto a highly oriented graphite (HOPG) surface as protofibrils and fibrils. The presence of the residues Leu (L), Phe (F), and Phe (F), which are also present in the native sequence, confirm that the peptides are able to bind to the aggregates of Aβ1-42 fibrils and protofibrils. Force of adhesion data were directly obtained from the maximum force on retraction, and the work of adhesion was calculated from the Jhonson-Kendall-Roberts model (JKR-Model). Both the polar and dispersive contributions to the surface energy of the peptides i0, i1, and i2, as well as Aβ1-42 fibrils and protofibrils, were determined by means of measuring the contact angle and using the two-fluid method. The macroscopic energies of the functionalized gold surfaces do not differ significantly between isomers, which confirms the similar nature of the peptides i0, i1, and i2 but suggests that the macroscopic measurements are not able to distinguish specific sequences. The nanoprobe reveals a typical adhesion work value associated with the interaction of protofibrils with i0 and i2; this value is three times higher than that of i1. The difference is attributed to the hydrophobic nature of protofibrils, the predominant exposition of hydrophobic residues of the peptides i0 and i2, with respect to i1, and the degree of functionalization. i0 and i2 presented a slight adhesion with Aβ fibrils, which is associated with the exposed hydrophilic groups of these fibrils (onto HOPG) compared to the protofibrils. However, i1 showed interaction with both Aβ fibrils and protofibrils. For this, we propose an explanation based on the fact that the peptide i1 locates

  20. Clinical and electrophysiological Signs of diabetic Polyneuropathy – EFFECT of Glycemia and Duration of Diabetes Mellitus

    OpenAIRE

    Kovač, Biserka; Kovač, Branislav; Marušić-Emedi, Slavica; Svalina, Sanja; Demarin, Vida

    2011-01-01

    Diabetic polyneuropathy occurs in around 50% of diabetic patients. Its pathophysiological mechanism is not completely clarified and major occurrences boil down to the change in neural phenotype and vasa nervorum. As glucose neurotoxicity has been suggested by plenty of evidence, the aim of the study was to assess the effect of glycemia on the severity of diabetic polyneuropathy. Considering that some practical experiences point to serious complications in patients suffering from diabetes of s...

  1. Clinical and electrophysiological signs of diabetic polyneuropathy -- effect of glycemia and duration of diabetes mellitus.

    Science.gov (United States)

    Kovac, Biserka; Kovac, Branislav; Marusić-Emedi, Slavica; Svalina, Sanja; Demarin, Vida

    2011-06-01

    Diabetic polyneuropathy occurs in around 50% of diabetic patients. Its pathophysiological mechanism is not completely clarified and major occurrences boil down to the change in neural phenotype and vasa nervorum. As glucose neurotoxicity has been suggested by plenty of evidence, the aim of the study was to assess the effect of glycemia on the severity of diabetic polyneuropathy. Considering that some practical experiences point to serious complications in patients suffering from diabetes of shorter duration, another aim was to assess the effect of diabetes duration on the severity of related neuropathy. Clinical and electromyoneurographic examinations were performed in 100 patients with diabetic polyneuropathy free from any laboratory signs of renal failure. The effect of HbA1c value and duration of disease on clinical symptoms, signs and electrophysiological indicators of polyneuropathy was analyzed. Study results indicated that 78% of patients with diabetic polyneuropathy did not have well-regulated glycemia. Diabetes duration was associated with a growing number of sensory symptoms, among which the sensation of pain similar to electric shock was present in 63% of patients. In addition, it also had negative impact on the sensory and motor nerve conduction velocity. HbA1c influenced the whole range of electrophysiological indicators of diabetic polyneuropathy.

  2. [Therapy of polyneuropathies. Causal and symptomatic].

    Science.gov (United States)

    Müller-Felber, W

    2001-05-28

    In the first instance, polyneuropathies are treated causally. The most common underlying cause is diabetes mellitus or alcohol abuse. In a large number of patients with polyneuropathy, however, the underlying cause cannot be definitively identified. For these--but equally for patients with etiologically clear polyneuropathy--a stock-taking of clinical symptoms should be carried out and, where indicated, symptomatic treatment initiated. In addition to medication aimed at combating pain, muscular spasm, autonomic functional disorders, and for the prevention of thrombosis, physical measures (physiotherapy, foot care, orthopedic shoes) are of primary importance.

  3. Characteristics of muscle cramps in patients with polyneuropathy.

    Science.gov (United States)

    Maxwell, Sarah K; Kokokyi, Seint; Breiner, Ari; Ebadi, Hamid; Bril, Vera; Katzberg, Hans D

    2014-08-01

    Muscle cramps are common in the general population and can be disabling for patients, but there is little evidence comprehensively evaluating cramp characteristics in patients with polyneuropathy. This study describes the prevalence and characteristics of muscle cramps in this patient group. Patients over 18 diagnosed with polyneuropathy were invited to join the study. Patients completed nerve conduction studies, the Toronto Clinical Neuropathy score, neuropathy-specific Vickrey's Quality of Life Assessment and a self-administered questionnaire examining demographics, neuropathy symptoms and cramp characteristics. Two hundred and twenty-five participants were enrolled (28.0% female). Sixty-three percent of patients experienced cramps, occurring on average 6 times per week, lasting 10.5 min and scoring 6 out of 10 on a pain scale and described as disabling by 43.6% of patients. No significant difference was found in cramp prevalence according to underlying pathophysiology (p = 0.52) or fiber type (p = 0.41). Patients with disabling cramps rated their physical (p cramps. This study confirms that muscle cramps are common, disabling and associated with reduced quality of life in patients with polyneuropathy. Similar prevalence of cramps across predominant nerve fiber type suggests a role of sensory afferents in cramp generation, although this needs to be confirmed in larger cohorts. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Correspondence between in vivo (11)C-PiB-PET amyloid imaging and postmortem, region-matched assessment of plaques.

    Science.gov (United States)

    Driscoll, Ira; Troncoso, Juan C; Rudow, Gay; Sojkova, Jitka; Pletnikova, Olga; Zhou, Yun; Kraut, Michael A; Ferrucci, Luigi; Mathis, Chester A; Klunk, William E; O'Brien, Richard J; Davatzikos, Christos; Wong, Dean F; Resnick, Susan M

    2012-12-01

    The definitive Alzheimer's disease (AD) diagnosis requires postmortem confirmation of neuropathological hallmarks-amyloid-β (Aβ) plaques and neurofibrillary tangles (NFTs). The advent of radiotracers for amyloid imaging presents an opportunity to investigate amyloid deposition in vivo. The (11)C-Pittsburgh compound-B (PiB)-PET ligand remains the most widely studied to date; however, regional variations in (11)C-PiB binding and the extent of agreement with neuropathological assessment have not been thoroughly investigated. Sojkova and colleagues [35] reported variable agreement between CERAD-based neuropathologic diagnosis of AD lesions and mean cortical PiB, suggesting the need for a more direct quantification of regional Aβ in relation to in vivo imaging. In the present study, we extend these findings by examining the correspondence among regional (11)C-PiB load, region-matched quantitative immunohistological assessments of Aβ and NFTs, and brain atrophy (MRI) in six older Baltimore Longitudinal Study of Aging participants who came to autopsy (imaging-autopsy interval range 0.2-2.4 years). The total number of Aβ plaques (6E10) and NFTs (PHF1) in paraffin sections from hippocampus, orbito-frontal cortex, anterior and posterior cingulate gyrus, precuneus and cerebellum was quantified using a technique guided by unbiased stereological principles. We report a general agreement between the regional measures of amyloid obtained via stereological assessment and imaging, with significant relationships evident for the anterior (r = 0.83; p = 0.04) and posterior (r = 0.94; p = 0.005) cingulate gyri, and the precuneus (r = 0.94; p = 0.005). No associations were observed between (11)C-PiB load and NFT count for any of the regions examined (p > 0.2 in all regions), or between regional Aβ or NFT counts and corresponding brain volumes. The strong associations of PiB retention with region-matched, quantitative analyses of Aβ in postmortem tissue offer

  5. MR-less surface-based amyloid assessment based on 11C PiB PET.

    Science.gov (United States)

    Zhou, Luping; Salvado, Olivier; Dore, Vincent; Bourgeat, Pierrick; Raniga, Parnesh; Macaulay, S Lance; Ames, David; Masters, Colin L; Ellis, Kathryn A; Villemagne, Victor L; Rowe, Christopher C; Fripp, Jurgen

    2014-01-01

    β-amyloid (Aβ) plaques in brain's grey matter (GM) are one of the pathological hallmarks of Alzheimer's disease (AD), and can be imaged in vivo using Positron Emission Tomography (PET) with (11)C or (18)F radiotracers. Estimating Aβ burden in cortical GM has been shown to improve diagnosis and monitoring of AD. However, lacking structural information in PET images requires such assessments to be performed with anatomical MRI scans, which may not be available at different clinical settings or being contraindicated for particular reasons. This study aimed to develop an MR-less Aβ imaging quantification method that requires only PET images for reliable Aβ burden estimations. The proposed method has been developed using a multi-atlas based approach on (11)C-PiB scans from 143 subjects (75 PiB+ and 68 PiB- subjects) in AIBL study. A subset of 20 subjects (PET and MRI) were used as atlases: 1) MRI images were co-registered with tissue segmentation; 2) 3D surface at the GM-WM interfacing was extracted and registered to a canonical space; 3) Mean PiB retention within GM was estimated and mapped to the surface. For other participants, each atlas PET image (and surface) was registered to the subject's PET image for PiB estimation within GM. The results are combined by subject-specific atlas selection and Bayesian fusion to generate estimated surface values. All PiB+ subjects (N = 75) were highly correlated between the MR-dependent and the PET-only methods with Intraclass Correlation (ICC) of 0.94, and an average relative difference error of 13% (or 0.23 SUVR) per surface vertex. All PiB- subjects (N = 68) revealed visually akin patterns with a relative difference error of 16% (or 0.19 SUVR) per surface vertex. The demonstrated accuracy suggests that the proposed method could be an effective clinical inspection tool for Aβ imaging scans when MRI images are unavailable.

  6. Recurrent Syncope, a Clue in Amyloid Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Julian A. Marin-Acevedo

    2018-01-01

    Full Text Available Infiltrative cardiomyopathies include a variety of disorders that lead to myocardial thickening resulting in a constellation of clinical manifestations and eventually heart failure that could be the first clue to reach the diagnosis. Among the more described infiltrative diseases of the heart is amyloid cardiomyopathy. The disease usually presents with subtle, nonspecific symptoms. Herein, we illustrate a case of recurrent syncope as the initial presenting symptom for systemic amyloid with polyneuropathy and cardiomyopathy as a cause of syncope. The article illustrates the role of advanced cardiac imaging in the diagnosis of the disease with a focused literature review. We also highlight the role of early, shared decision-making between patient, family, and medical team in the management of cardiac amyloidosis.

  7. Can Mustard Gas Induce Late Onset Polyneuropathy?

    Directory of Open Access Journals (Sweden)

    SJ. Mousavi

    2007-11-01

    Full Text Available Background:Mustard gas, lethal in high doses, affects multiple organs such as skin, eye and respiratory system. We studied the development of late onset mustardinduced polyneuropathy among chemically wounded Iranian veterans.Methods:In this descriptive study,100 chemically wounded Iranian veterans with severe eye involvement were examined for any signs and symptoms of polyneuropathy by an internist.20 patients were suspected to have neurological symptoms or signs.These patients were examined by a neurologist again. 13 showed abnormal neurological symptoms. Electrodiagnostic exams were performed for this group by another physician.Results:13 veterans had abnormal neurological exam results with prominent sensory signs and symptoms in almost all of them. Brisk deep tendon reflexes were found in 3 cases. Electrodiagnostic studies were compatible with axonal type distal sensory polyneuropathy in 6 subjects. Conclusion: To the best of our knowledge, this is the first report of late onset polyneuropathy among chemically-wounded victims who were exposed to mustard gas. The pathophysiology of this form of neuropathy is still unknown. Unlike most toxic neuropathies,obvious clinical signs and symptoms appeared several years after exposure. No specific treatment for.polyneuropathy due to chemical weapons exposure has been described to date.

  8. Association between Diabetic Polyneuropathy and Cardiovascular Complications in Type 2 Diabetic Patients

    OpenAIRE

    Jin Ook Chung; Dong Hyeok Cho; Dong Jin Chung; Min Young Chung

    2011-01-01

    Background Diabetes mellitus is a major independent risk factor for cardiovascular disease (CVD), but high cardiovascular risk in diabetes mellitus patients is not completely explained by clustering traditional risk factors. Recently, associations between diabetic polyneuropathy (DPN) and macrovasculopathy have been suggested. We aimed to assess associations between DPN and cardiovascular complications in type 2 diabetic patients. Methods Microvascular and cardiovascular complications were ev...

  9. Pathological features of polyneuropathy in three dogs.

    Science.gov (United States)

    Tsuboi, Masaya; Uchida, Kazuyuki; Ide, Tetsuya; Ogawa, Mizue; Inagaki, Takehiko; Tamura, Shinji; Saito, Miyoko; Chambers, James K; Nakayama, Hiroyuki

    2013-01-01

    Canine polyneuropathy is a neurological disorder characterized by a dysfunction of multiple peripheral nerves. The etiology of the disease is diverse; it may occur in cases of infectious, immune-mediated, or hereditary conditions or in association with endocrinopathy, neoplasm, or chemical intoxication. It is often difficult to determine the etiology through clinical symptoms. The aim of this study is to investigate pathological differences among three canine polyneuropathy cases with each presumably having a different etiology. Cases included a 13-month-old female border collie (Dog No.1), a 21-month-old male chihuahua (Dog No.2) and an 11-year-old male beagle (Dog No.3). Clinical examinations revealed hindlimb ataxia and sensory loss in Dog No.1, forelimb paralysis and vertebral pain in Dog No.2, and paddling-gait and hypothyroidism in Dog No.3. Histopathologically, axonal swelling and pale myelin were observed in Dog No.1. Giant axons mimicking giant axonal neuropathy were obvious in Dog No.2. Dog No.3 showed atrophic axons and severe interstitial edema. Distributions of peripheral nerve lesions coincided with respective clinical symptoms. According to their clinical and pathological features, Dogs No.1 and No.2 were suspected of hereditary polyneuropathy, while Dog No.3 seemed to have hypothyroidism-associated polyneuropathy. As each case demonstrated unique pathological features, different pathogeneses of peripheral nerve dysfunction were suggested.

  10. Chronic inflammatory demyelinating polyneuropathy: a case report ...

    African Journals Online (AJOL)

    Chronic inflammatory demyelinating polyneuropathy: a case report and review of the literature. ... Vol 12, No 1 (2013) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access ...

  11. Assessment of serum amyloid A testing of horses and its clinical application in a specialized equine practice.

    Science.gov (United States)

    Belgrave, Rodney L; Dickey, Meranda M; Arheart, Kristopher L; Cray, Carolyn

    2013-07-01

    To compare serum amyloid A (SAA) concentration, plasma fibrinogen concentration, total WBC count, and serum albumin-to-globulin concentration ratio (A:G ratio) in clinically normal (CN) and clinically abnormal (CA) horses. Prospective cohort study. 111 CN horses and 101 CA horses hospitalized at a specialty clinical practice. Shortly after admission, a blood sample (20 mL) was collected from each horse for a CBC, serum protein electrophoresis, and determination of plasma fibrinogen concentration; SAA concentration was assessed with a previously validated immunoturbidometric assay. Similar testing of a subset of CA horses was conducted at various points during treatment. Total WBC count, A:G ratio, and SAA concentration were determined for all 212 horses; data regarding plasma fibrinogen concentration were available for 127 horses (of which 47 were CN and 80 were CA). Median SAA concentration, total WBC count, and plasma fibrinogen concentration and mean A:G ratio differed significantly between CN horses and CA horses. Correlations between these variables were poor to weak. For discrimination of CN horses from CA horses, the SAA assay had sensitivity of 53% and specificity of 94% (diagnostic accuracy, 75%); for the other assessments, accuracy ranged from 59% to 62%. Repeated assessment of SAA concentration in some CA horses revealed a gradual return to normal concentrations. Results indicated that assessment of SAA concentration can provide valuable information regarding the clinical state of horses and may be more useful for patient monitoring and as a prognostic indicator than are traditional markers of inflammation.

  12. [Amyloid goiter].

    Science.gov (United States)

    Hrívó, A; Péter, I; Bánkúti, B; Péley, G; Baska, F; Besznyák, I

    1999-03-21

    Amyloid goitre is at an extremely rare occurrence. Authors review the origin of disease and its symptoms, diagnostic and therapeutic tools. The disease may be due to either primary or secondary systemic or local amyloidosis. Diagnosis may be made even before surgery on anamnestic data, on very rapid growth of thyroid glands, on diffuse appearance, on other symptoms of systemic amyloidosis, on findings of iconographic procedures and on detection of amyloid in aspirates. Final diagnosis is based on histology. Surgical therapy is aiming at avoidance of the existing and the threatening consequences of expanding mass. The outcome is independent from thyroid surgery, it is related to other manifestations of amyloidosis. Concerning with the present case the chronic superior vena cava syndrome and chylous pleural effusion as first described symptoms and asymptomatic hyperthyroxinaemia is emphasised. Neither other organ involvement, nor primary amyloidogenous molecula was found during the 18 months follow up, so patient has secondary and localised amyloidosis.

  13. Selected Physical Therapy Modalities for the treatment of Diabetic Polyneuropathy

    International Nuclear Information System (INIS)

    Sawan, S.; Sayed, N.; Al-Gazzar, S.

    2006-01-01

    The purpose of this study was to examine the effect of using selected physical therapy modalities for the treatment of diabetic polyneuropathy. Thirty patients participated in this study. Patients were randomly divided into study group (ten males and five females) and control group (six males and nine females). The study group received interferential current on the lumbosacral region, followed by repeated contraction as specific technique of proprioceptive neuromuscular facilitation (PNF) to the anterior tibial group muscles. The control group did not receive physical therapy treatment. The treatment for the study group was conducted three times per week, for a period of six weeks. The patients were assessed for intensity of pain, manual muscle testing of the anterior tibial group muscles, and the level of superficial sensation on their feet. Patients were assessed the beginning of the treatment session and after the last session. The result of this study showed a significant decrease in the pain intensity, increase anterior tibial group muscles strength and increase level of superficial sensation in patients of study group in comparison to the control group at the end of the treatment. The control group did not show significant changes. It can be concluded that the combination of interferential current and repeated contraction (specific technique of PNF to the anterior tibial group muscles) is effective in decreasing the pain, increasing anterior tibial group muscles strength and the level of superficial sensation in patients suffering from diabetic polyneuropathy. (author)

  14. Kinetic studies with iodine-123-labeled serum amyloid P component in patients with systemic AA and AL amyloidosis and assessment of clinical value

    NARCIS (Netherlands)

    Jager, PL; Hazenberg, BPC; Franssen, EJF; Limburg, PC; van Rijswijk, MH; Piers, DA

    In systemic amyloidosis, widespread amyloid deposition interferes with organ function, frequently with fatal consequences. Diagnosis rests on demonstrating amyloid deposits in the tissues, traditionally with histology although scintigraphic imaging with radiolabeled serum amyloid P component (SAP)

  15. Diagnosis of Late Stage, Early Onset, Small Fiber Polyneuropathy

    Science.gov (United States)

    2016-10-01

    polyneuropathy underlies some illnesses currently labeled as fibromyalgia. Pain 2013; 154:2310-2316. 2. Oaklander AL and...Patient Data Registry SFPN Small-fiber polyneuropathy USAMRMC US Army Medical Research and Materiel Command VA Veterans Administration VSO Veterans’ Service Organization WRIISC War-Related Illness and Injury Study Center ...AWARD NUMBER: W81XWH-15-1-0683 TITLE: Diagnosis of Late-Stage, Early-Onset, Small-Fiber Polyneuropathy PRINCIPAL INVESTIGATOR: Anne

  16. Health, Social and Economic Consequences of Polyneuropathy

    DEFF Research Database (Denmark)

    Jennum, Poul; Ibsen, Rikke; Kjellberg, Jakob

    2015-01-01

    socioeconomic costs than controls. They had very marginally lower employment rates, and those who were employed generally had lower incomes. The sum of direct net healthcare costs after the injury (general practitioner services, hospital services and medication) and indirect costs (loss of labor market income......OBJECTIVES: To estimate the direct and indirect factual costs of polyneuropathy in a national sample of patients and their spouses based on a national register-based cohort study with matched controls. METHODS: Using records from the Danish National Patient Registry (1997-2009) all patients...... with a diagnosis of polyneuropathy and their partners were identified and compared with randomly chosen controls matched for age, gender, geographic area and civil status. Direct costs included frequencies of primary and secondary sector contacts and procedures, and medication. Indirect costs included the effect...

  17. Transplantation of dental pulp stem cells improves long-term diabetic polyneuropathy together with improvement of nerve morphometrical evaluation.

    Science.gov (United States)

    Omi, Maiko; Hata, Masaki; Nakamura, Nobuhisa; Miyabe, Megumi; Ozawa, Shogo; Nukada, Hitoshi; Tsukamoto, Masami; Sango, Kazunori; Himeno, Tatsuhito; Kamiya, Hideki; Nakamura, Jiro; Takebe, Jun; Matsubara, Tatsuaki; Naruse, Keiko

    2017-12-13

    Although previous reports have revealed the therapeutic potential of stem cell transplantation in diabetic polyneuropathy, the effects of cell transplantation on long-term diabetic polyneuropathy have not been investigated. In this study, we investigated whether the transplantation of dental pulp stem cells (DPSCs) ameliorated long-term diabetic polyneuropathy in streptozotocin (STZ)-induced diabetic rats. Forty-eight weeks after STZ injection, we transplanted DPSCs into the unilateral hindlimb skeletal muscles. Four weeks after DPSC transplantation (i.e., 52 weeks after STZ injection) the effects of DPSC transplantation on diabetic polyneuropathy were assessed. STZ-induced diabetic rats showed significant reductions in the sciatic motor/sensory nerve conduction velocity, increases in the current perception threshold, and decreases in capillary density in skeletal muscles and intra-epidermal nerve fiber density compared with normal rats, all of which were ameliorated by DPSC transplantation. Furthermore, sural nerve morphometrical analysis revealed that the transplantation of DPSCs significantly increased the myelin thickness and area. DPSC-conditioned media promoted the neurite outgrowth of dorsal root ganglion neurons and increased the viability and myelin-related protein expression of Schwann cells. These results indicated that the transplantation of DPSCs contributed to the neurophysiological and neuropathological recovery from a long duration of diabetic polyneuropathy.

  18. Multimodal imaging Gd-nanoparticles functionalized with Pittsburgh compound B or a nanobody for amyloid plaques targeting.

    Science.gov (United States)

    Pansieri, Jonathan; Plissonneau, Marie; Stransky-Heilkron, Nathalie; Dumoulin, Mireille; Heinrich-Balard, Laurence; Rivory, Pascaline; Morfin, Jean-François; Toth, Eva; Saraiva, Maria Joao; Allémann, Eric; Tillement, Olivier; Forge, Vincent; Lux, François; Marquette, Christel

    2017-07-01

    Gadolinium-based nanoparticles were functionalized with either the Pittsburgh compound B or a nanobody (B10AP) in order to create multimodal tools for an early diagnosis of amyloidoses. The ability of the functionalized nanoparticles to target amyloid fibrils made of β-amyloid peptide, amylin or Val30Met-mutated transthyretin formed in vitro or from pathological tissues was investigated by a range of spectroscopic and biophysics techniques including fluorescence microscopy. Nanoparticles functionalized by both probes efficiently interacted with the three types of amyloid fibrils, with K D values in 10 micromolar and 10 nanomolar range for, respectively, Pittsburgh compound B and B10AP nanoparticles. Moreover, they allowed the detection of amyloid deposits on pathological tissues. Such functionalized nanoparticles could represent promising flexible and multimodal imaging tools for the early diagnostic of amyloid diseases, in other words, Alzheimer's disease, Type 2 diabetes mellitus and the familial amyloidotic polyneuropathy.

  19. How to work up a patient with polyneuropathy?

    LENUS (Irish Health Repository)

    Renganathan, R

    2009-01-01

    Undiagnosed and untreated neuropathy may lead to disability and poor quality of life. Ordering every possible test to find the cause of polyneuropathy can waste time and resources. In this study, we investigated what could be used as a routine neuropathy screen. A retrospective audit of all charts of patients diagnosed to have polyneuropathy by nerve conduction studies from November 2001 to November 2002 were carried out. Demographics, background history, type of neuropathy and investigations done were documented. The charts of 61 patients were audited. 12 patients had a background history of diabetes mellitus. 2 patients had history of alcohol abuse. 23 patients presented with paraesthesia and 33 with weakness of limbs. We found a cause of polyneuropathy in 79% of cases. In most patients with polyneuropathy where a cause can be identified, this can be achieved by the medical history, neurological examination, nerve conduction studies and the baseline blood tests. We suggest a 3-step approach to the diagnostic workup of polyneuropathy.

  20. Functional Amyloids in Reproduction.

    Science.gov (United States)

    Hewetson, Aveline; Do, Hoa Quynh; Myers, Caitlyn; Muthusubramanian, Archana; Sutton, Roger Bryan; Wylie, Benjamin J; Cornwall, Gail A

    2017-06-29

    Amyloids are traditionally considered pathological protein aggregates that play causative roles in neurodegenerative disease, diabetes and prionopathies. However, increasing evidence indicates that in many biological systems nonpathological amyloids are formed for functional purposes. In this review, we will specifically describe amyloids that carry out biological roles in sexual reproduction including the processes of gametogenesis, germline specification, sperm maturation and fertilization. Several of these functional amyloids are evolutionarily conserved across several taxa, including human, emphasizing the critical role amyloids perform in reproduction. Evidence will also be presented suggesting that, if altered, some functional amyloids may become pathological.

  1. Risk Factors for Incident Diabetic Polyneuropathy in a Cohort With Screen-Detected Type 2 Diabetes Followed for 13 Years

    DEFF Research Database (Denmark)

    Andersen, Signe T; Witte, Daniel R; Dalsgaard, Else-Marie

    2018-01-01

    OBJECTIVE: To study incident diabetic polyneuropathy (DPN) prospectively during the first 13 years after a screening-based diagnosis of type 2 diabetes and determine the associated risk factors for the development of DPN. RESEARCH DESIGN AND METHODS: We assessed DPN longitudinally in the Danish arm...

  2. Amyloid and immune homeostasis.

    Science.gov (United States)

    Wang, Ying-Hui; Zhang, Yu-Gen

    2018-03-01

    Extracellular amyloid deposition defines a range of amyloidosis and amyloid-related disease. Addition to primary and secondary amyloidosis, amyloid-related disease can be observed in different tissue/organ that sharing the common pathogenesis based on the formation of amyloid deposition. Currently, both Alzheimer's disease and type 2 diabetes can be diagnosed with certainly only based on the autopsy results, by which amyloidosis of the associative tissue/organ is observed. Intriguingly, since it demonstrated that amyloid deposits trigger inflammatory reaction through the activation of cascaded immune response, wherein several lines of evidence implies a protective role of amyloid in preventing autoimmunity. Furthermore, attempts for preventing amyloid formation and/or removing amyloid deposits from the brain have caused meningoencephalitis and consequent deaths among the subjects. Hence, it is important to note that amyloid positively participates in maintaining immune homeostasis and contributes to irreversible inflammatory response. In this review, we will focus on the interactive relationship between amyloid and the immune system, discussing the potential functional roles of amyloid in immune tolerance and homeostasis. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Amyloid detection in the transverse carpal ligament of patients with hereditary ATTR V30M amyloidosis and carpal tunnel syndrome.

    Science.gov (United States)

    Samões, Raquel; Taipa, Ricardo; Valdrez, Kátia; Gonçalves, Isabel; Melo Pires, Manuel; Martins da Silva, Ana; Coelho, Teresa

    2017-06-01

    Carpal tunnel syndrome (CTS) is a nonspecific manifestation of hereditary ATTR amyloidosis (ATTRm). Amyloid deposition of wild-type TTR (WT-ATTR) has been found in transverse carpal ligament (TCL) in idiopathic CTS. We retrospectively studied a group of patients with ATTRm and CTS submitted to carpal tunnel release surgery (CTRS). From the nerve conduction studies performed in our Clinical Unit dedicated to hereditary amyloidosis between July 2009 and October 2013, we selected patients who fulfilled neurophysiological criteria for CTS, had been submitted to CTRS and whose TCL was available for pathology. Clinical registries were reviewed and amyloid detection in the ligaments was performed using Congo-red staining. We included 16 patients: three males (18.8%), mean age = 46.1 years old, all with V30M mutation. At the time of surgery, four patients were considered asymptomatic and 12 symptomatic carriers, five of them late-onset ATTRm (onset age >50 years old). In all but one patient, the CTS preceded the polyneuropathy. Amyloid detection in the TCL was positive in 14 patients (87.5%). In most patients, CTS preceded or was contemporary to the polyneuropathy and amyloid detection in TCL was positive. The detection of amyloid in TCL may add specificity to CTS as an early manifestation of the disease but more studies are needed.

  4. Detection of diphtheritic polyneuropathy by acute flaccid paralysis surveillance, India.

    Science.gov (United States)

    Mateen, Farrah J; Bahl, Sunil; Khera, Ajay; Sutter, Roland W

    2013-01-01

    Diphtheritic polyneuropathy is a vaccine-preventable illness caused by exotoxin-producing strains of Corynebacterium diphtheriae. We present a retrospective convenience case series of 15 children (6 girls)paralysis surveillance, which was designed to detect poliomyelitis in India during 2002-2008. We also report data on detection of diphtheritic polyneuropathy compared with other causes of acute flaccid paralysis identified by this surveillance system.

  5. Peripheral polyneuropathy after bariatric surgery for morbid obesity

    OpenAIRE

    I-Ching Lin; Ying Li Lin

    2011-01-01

    A patient with peripheral polyneuropathy after bariatric surgery for morbid obesity is reported. She suffered from frequent episodes of vomiting and abdominal pain after surgery. Muscle weakness in her lower limbs developed 5 months later and she experienced difficulty in walking and standing. Wrist drop, foot drop, and marked distal limb muscle atrophy were found bilaterally. Electromyography showed the presence of sensorimotor axonal polyneuropathy. Nutritional deficiencies may play an impo...

  6. Imipramine and pregabalin combination for painful polyneuropathy

    DEFF Research Database (Denmark)

    Holbech, Jakob V; Bach, Flemming W; Finnerup, Nanna B

    2015-01-01

    scores than both monotherapies: combination vs imipramine (P = 0.009), combination vs pregabalin (P combination therapy, the dropout rate was higher and the patients reported a higher rate and severity of side effects. Combination of moderate doses of the tricyclic antidepressant......Monotherapy with first-line drugs for neuropathic pain often fails to provide sufficient pain relief or has unacceptable side effects because of the need for high doses. The aim of this trial was to test whether the combination of imipramine and pregabalin in moderate doses would relieve pain more...... effectively than monotherapy with either of the drugs. This was a randomized, double-blind, placebo-controlled, crossover, multicenter trial consisting of four 5-week treatment periods in patients with painful polyneuropathy. Treatment arms were imipramine 75 mg/d vs pregabalin 300 mg/d vs combination therapy...

  7. Pharmacologic treatment of pain in polyneuropathy

    DEFF Research Database (Denmark)

    Sindrup, Søren H.; Jensen, Troels Staehelin

    2000-01-01

    Tricyclic antidepressants and anticonvulsants have become the mainstay in the treatment of pain in polyneuropathy. Within the last decade, controlled trials have shown that numerous other drugs relieve such pain. To estimate the efficacy of the different treatments, the authors identified all...... placebo-controlled trials and calculated numbers needed to treat (NNT) to obtain one patient with more than 50% pain relief. The NNT was 2.6 for tricyclic antidepressants, 6.7 for selective serotonin reuptake inhibitors, 2.5 for anticonvulsant sodium channel blockers, 4.1 for the anticonvulsant calcium...... channel blocker gabapentin, and 3.4 for the mixed opioid and monoaminergic drug tramadol, as calculated from a sufficiently large number of patients. Favorable point estimates of NNT of 1.9 for the NMDA-antagonist dextromethorphan and 3.4 for L-dopa were determined from a limited number of data...

  8. [Critical illness polyneuropathy and critical illness myopathy].

    Science.gov (United States)

    Grimm, A; Günther, A; Witte, O W; Axer, H

    2012-11-01

    Critical illness polyneuropathy (CIP) and critical illness myopathy (CIM) are frequent complications in critically ill patients and both are associated with sepsis, systemic inflammatory response syndrome (SIRS) and multiorgan failure. Major signs are muscle weakness and problems of weaning from the ventilator. Both CIP and CIM lead to elongated times of ventilation, elongated hospital stay, elongated times of rehabilitation and increased mortality. Electrophysiological measurements help to detect CIP and CIM early in the course of the disease. State of the art sepsis therapy is the major target to prevent the development of CIP and CIM. Although no specific therapy of CIP and CIM has been established in the past, the diagnosis generally improves the therapeutic management (weaning from the ventilator, early physiotherapy, etc.). This review provides an overview of clinical and diagnostic features of CIP and CIM and summarizes current pathophysiological and therapeutic concepts.

  9. Update on the management of diabetic polyneuropathies

    Directory of Open Access Journals (Sweden)

    Shakher J

    2011-07-01

    Full Text Available Jayadave Shakher1, Martin J Stevens1,21Heart of England NHS Foundation Trust, Birmingham, UK; 2School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UKAbstract: The prevalence of diabetic polyneuropathy (DPN can approach 50% in subjects with longer-duration diabetes. The most common neuropathies are generalized symmetrical chronic sensorimotor polyneuropathy and autonomic neuropathy. It is important to recognize that 50% of subjects with DPN may have no symptoms and only careful clinical examination may reveal the diagnosis. DPN, especially painful diabetic peripheral neuropathy, is associated with poor quality of life. Although there is a better understanding of the pathophysiology of DPN and the mechanisms of pain, treatment remains challenging and is limited by variable efficacy and side effects of therapies. Intensification of glycemic control remains the cornerstone for the prevention or delay of DPN but optimization of other traditional cardiovascular risk factors may also be of benefit. The management of DPN relies on its early recognition and needs to be individually based on comorbidities and tolerability to medications. To date, most pharmacological strategies focus upon symptom control. In the management of pain, tricyclic antidepressants, selective serotonin noradrenaline reuptake inhibitors, and anticonvulsants alone or in combination are current first-line therapies followed by use of opiates. Topical agents may offer symptomatic relief in some patients. Disease-modifying agents are still in development and to date, antioxidant α-lipoic acid has shown the most promising effect. Further development and testing of therapies based upon improved understanding of the complex pathophysiology of this common and disabling complication is urgently required.Keywords: diabetes, neuropathic pain, microvascular, glucose 

  10. A standardized clinical evaluation of phenotypic diversity in diabetic polyneuropathy.

    Science.gov (United States)

    Scholz, Joachim; Rathmell, James P; David, William S; Chad, David A; Broderick, Alithia C; Perros, Stephen G; Shin, Naomi S; Wells, Jenna L; Davis, John B; DiMaggio, Charles J; Wang, Shuang; Tate, Simon N

    2016-10-01

    Diabetic polyneuropathy (DPN) is a major cause of neuropathic pain and a frequent target condition in analgesic treatment trials. Differences in the clinical symptoms and signs associated with DPN suggest distinct pathophysiological mechanisms underlying nerve damage and dysfunction that are likely to have therapeutic relevance. The aim of this study was to develop a tool for the bedside assessment of painful neuropathies such as DPN that captures the diversity of phenotypes. Sixty-one patients with type 2 diabetes and painful neuropathy, 19 patients with painless DPN, 25 patients with type 2 diabetes but no clinical evidence of neuropathy, and 20 healthy control subjects completed a structured interview (47 items) and a standardized physical examination (39 items). After analyzing critical features of pain and painless symptoms and examining the outcome of physical tests of sensory function, we determined principal components of the phenotypic variance among patients. Increased sensitivity to mechanical or thermal stimuli and, to a lesser extent, the sensory quality of pain or paresthesia were the most discriminating elements of DPN phenotypes. Correlation patterns of symptoms and signs indicated the involvement of functionally distinct nerve fiber populations. We combined interview questions and physical tests identifying these differences in a shortened assessment protocol that we named Standardized Evaluation of Pain and Somatosensory Function (StEPS). The protocol StEPS generates a phenotypic profile of patients with neuropathy. Separate intensity ratings for spontaneous painful symptoms and pain evoked by standard stimuli support a detailed documentation of neuropathic pain and its response to analgesic treatment.

  11. Small Nerve Fiber Quantification in the Diagnosis of Diabetic Sensorimotor Polyneuropathy: Comparing Corneal Confocal Microscopy With Intraepidermal Nerve Fiber Density

    OpenAIRE

    Chen, Xin; Graham, Jim; Dabbah, Mohammad A.; Petropoulos, Ioannis N.; Ponirakis, Georgios; Asghar, Omar; Alam, Uazman; Marshall, Andrew; Fadavi, Hassan; Ferdousi, Maryam; Azmi, Shazli; Tavakoli, Mitra; Efron, Nathan; Jeziorska, Maria; Malik, Rayaz A.

    2015-01-01

    OBJECTIVE Quantitative assessment of small fiber damage is key to the early diagnosis and assessment of progression or regression of diabetic sensorimotor polyneuropathy (DSPN). Intraepidermal nerve fiber density (IENFD) is the current gold standard, but corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, has the potential to be a noninvasive and objective image biomarker for identifying small fiber damage. The purpose of this study was to determine the diagnostic perfo...

  12. Small nerve fibre quantification in the diagnosis of diabetic sensorimotor polyneuropathy: comparing corneal confocal microscopy with intraepidermal nerve fibre density

    OpenAIRE

    Chen, Xin; Graham, Jim; Dabbah, Mohammad; Petropoulos, Ioannis N.; Ponirakis, Georgis; Asghar, Omar; Alam, Uazman; Marshall, Andrew; Fadavi, Hassan; Ferdousi, Maryam; Azmir, Shazli; Tavakoli, Mitra; Efron, Nathan; Jeziorska, Maria; Malik, Rayaz

    2015-01-01

    OBJECTIVE: Quantitative assessment of small fiber damage is key to the early diagnosis and assessment of progression or regression of diabetic sensorimotor polyneuropathy (DSPN). Intraepidermal nerve fiber density (IENFD) is the current gold standard, but corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, has the potential to be a noninvasive and objective image biomarker for identifying small fiber damage. The purpose of this study was to determine the diagnostic perf...

  13. Validation of the Toronto Clinical Scoring System for diabetic polyneuropathy.

    Science.gov (United States)

    Bril, Vera; Perkins, Bruce A

    2002-11-01

    The aim of the current study was to determine the validity of the Toronto Clinical Scoring System (CSS) in reflecting the presence and severity of diabetic peripheral sensorimotor polyneuropathy (DSP) as determined by myelinated fiber density (FD) on sural nerve biopsy. Eighty-nine patients with both type 1 and type 2 diabetes, ascertained from a large therapeutic randomized controlled trial, were included in this cross-sectional, observational cohort study. Morphological severity of DSP was expressed as the FD in the sural nerve biopsy. The Toronto CSS was applied to all patients to determine a clinical neuropathy score. General linear regression models were used to assess the relationship between the morphological severity of DSP and the Toronto CSS. The Toronto CSS showed a significant negative correlation with sural nerve FD (R(2) = 0.256, P current study underscore the interrelationships between clinical deficits, electrophysiological findings, and morphological changes in DSP. This evidence suggests that the Toronto CSS may prove useful in documenting and monitoring DSP in the clinic and in clinical research trials.

  14. Histopathological confirmation of polyneuropathy in 11 dogs with laryngeal paralysis.

    Science.gov (United States)

    Thieman, Kelley M; Krahwinkel, D J; Sims, Michael H; Shelton, G Diane

    2010-01-01

    Acquired laryngeal paralysis (LP) is an important cause of upper airway obstruction in dogs. We hypothesize that LP may be part of a generalized polyneuropathy complex. Electro-diagnostic studies were performed in six dogs, and histopathological studies of muscle and nerve biopsies were obtained from 11 dogs diagnosed with acquired LP. Abnormalities in electrodiagnostic procedures were consistent with a generalized polyneuropathy. Loss of large-caliber nerve fibers and axonal degeneration were identified in nerve biopsies, and neurogenic atrophy was observed in muscle specimens. Abnormalities in electrodiagnostic studies and histopathology provide evidence that LP may be part of a generalized polyneuropathy. Establishing a diagnosis of a more involved disease process is relevant for long-term prognosis.

  15. Randomized controlled trial of the combined monoaminergic and opioid investigational compound GRT9906 in painful polyneuropathy

    DEFF Research Database (Denmark)

    Sindrup, S H; Konder, R; Lehmann, R

    2012-01-01

    GRT9906 is an investigational novel compound with μ-opioid receptor agonism and inhibition of noradrenalin/serotonin re-uptake. In this randomized, double-blind, placebo-controlled, three-way cross-over trial in painful polyneuropathy, the efficacy and safety of GRT9906 was assessed and compared...... with tramadol. During 4-week treatment periods, daily oral doses of either GRT9906 120-240 mg, or placebo, or tramadol 200-400 mg were given. These were separated by 1-week washout periods. The primary endpoint was the average pain intensity (average of daily current pain intensity over the last 3 days of each...

  16. Confocal Cornea Microscopy Detects Involvement of Corneal Nerve Fibers in a Patient with Light-Chain Amyloid Neuropathy Caused by Multiple Myeloma: A Case Report

    Directory of Open Access Journals (Sweden)

    Dietrich Sturm

    2016-06-01

    Full Text Available Changes in the subbasal corneal plexus detected by confocal cornea microscopy (CCM have been described for various types of neuropathy. An involvement of these nerves within light-chain (AL amyloid neuropathy (a rare cause of polyneuropathy has never been shown. Here, we report on a case of a patient suffering from neuropathy caused by AL amyloidosis and underlying multiple myeloma. Small-fiber damage was detected by CCM.

  17. Critical illness polyneuropathy and myopathy in pediatric intensive care: A review.

    Science.gov (United States)

    Williams, Stephen; Horrocks, Iain A; Ouvrier, Robert A; Gillis, Jonathan; Ryan, Monique M

    2007-01-01

    To review the medical literature on critical illness polyneuropathy and myopathy in childhood. Medline and EMBASE were searched using the following terms: critical illness (neuropathy, polyneuropathy, and myopathy), critical care (neuropathy, polyneuropathy, and myopathy), acute myopathy, acute necrotizing myopathy, children, and pediatric. The references listed in publications thus identified were also reviewed. All studies relating to pediatric critical illness polyneuropathy and myopathy were included. The adult literature was also reviewed as to the current understanding of critical illness polyneuropathy and myopathy. Critical illness polyneuropathy and critical illness myopathy are well recognized in adults, in whom they commonly cause generalized weakness and muscle wasting, with failure to wean from mechanical ventilation. Critical illness polyneuropathy and critical illness myopathy are reported in 32-100% of critically ill adult patients ventilated for >3 days. There is significant clinical and neurophysiologic overlap between the two conditions, such that the term critical illness polyneuropathy and myopathy (CIPNM) is often used. Critical illness polyneuropathy and critical illness myopathy have only occasionally been reported in childhood, and little is known of their prevalence or clinical significance in this population. This article summarizes the pediatric literature on critical illness polyneuropathy and critical illness myopathy and highlights areas for future research in critically ill children. Critical illness polyneuropathy and myopathy may cause significant morbidity in critically ill children. These conditions seem to be clinically and electrophysiologically similar in children and adults, but prospective studies of these entities are required to better characterize their frequency, natural history, and clinical significance in pediatric practice.

  18. Corneal sensitivity in chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Bansal, Surbhi; Myneni, Ajay A; Mu, Lina; Myers, Bennett H; Patel, Sangita P

    2014-07-01

    Neurotrophic keratitis may result from a variety of ocular or systemic diseases. Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune neuropathy that affects any nerve plexus but with no known association with corneal disease. We observed 2 patients with CIDP and visually compromising neurotrophic corneal ulcers. This study was performed to determine the prevalence of neurotrophic corneas in patients with CIDP to identify a subpopulation of asymptomatic patients who are at risk for vision loss. This is an observational case series of 2 patients with CIDP with visually compromising neurotrophic corneal ulcers and a prospective clinical study comparing corneal sensitivity in 9 patients with CIDP versus 9 age- and sex-matched controls. Corneal sensitivity was tested with an esthesiometer. Statistical analyses were performed to determine patterns or significances in relation to the subject's age, gender, and duration and severity of the disease. The overall median corneal sensitivity was 5.7 for patients with CIDP and 6.0 for controls (P = 0.09). The mean corneal sensitivity was 5.6 ± 0.4 in patients with CIDP compared with 5.8 ± 0.3 in controls. No specific pattern was found with age, gender, or duration and severity of the disease among patients with CIDP. Although the case series demonstrated decreased corneal sensitivity in both patients with CIDP, the prospective study detected reduced corneal sensitivity in patients with CIDP when compared with controls, but did not reach statistical significance. Ophthalmic examinations with measurement of corneal sensitivity should be considered in the management of patients with CIDP.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01379833.

  19. Biochemical nature of familial amyloiditic polyneuropathy and a new diagnostic method by radioimmunoassay

    International Nuclear Information System (INIS)

    Nakazato, M.; Kanagawa, K.; Kurihara, T.

    1986-01-01

    Familial amyloidotic polyneuropathy (FAP) in Japan is clinically similar to that of Portugal. We have reported that amyloid fibril protein isolated from Japanese FAP cases is composed of a prealbumin variant in which a valine residue at position 30 is replaced by a methionine (Tawara et al., 1983). Furthermore, we have clarified that this prealbumin variant is present in the sera of Japanese FAP patients. There has been no definite method to detect this progressive illness before clinical manifestations appear. For the purpose of developing a new, noninvasive diagnostic method, we have established a radioimmunoassay (RIA) using a nonapeptide corresponding to the subsequence (22-30) of the prealbumin variant. The serum levels of the prealbumin variant in normal individuals, FAP patients, asymptomatic members of FAP families, primary and secondary amyloidosis cases are studied. The present RIA serves as a simple and definite method for an early detection of this disease and an appropriate genetic advice can be given to FAP patients and their families

  20. Correlation of clinical and neurophysiological findings with health related quality of life in patients with diabetic polyneuropathy

    Directory of Open Access Journals (Sweden)

    Vukojević Zoran

    2014-01-01

    Full Text Available Background/Aim. Diabetic polyneuropathy is defined as the presence of clinical or subclinical symptoms and/or signs of peripheral nerve damage in patients with diabetes mellitus in the absence of the other causes of peripheral neuropathy. The aim of this study was to assess healthrelated quality of life (HRQoL in patients with diabetic polyneuropathy and its correlation with clinical and neurophysiological findings. Methods. This study comprised 60 patients with distal, symmetric, sensorimotor diabetic polyneuropathy and type 2 diabetes mellitus. For evaluation of clinical findings the following scales were used: Medical Research Council strenth score (MRC sum score, Inflammatory Neuropathy Cause and Treatment (INCAT disability scale (arm disability and leg disability scales, INCAT sensory sum score, Hamilton depression and anxiety rating scales. Nerve conduction study (NCS was performed on the motor part of the median and peroneal nerves, the sensory part of the median nerve and sural nerve. All the patients completed the Serbian version of the SF-36 questionnaire as a measure of HRQoL. Results. Our results showed mild to moderate QoL impairment in the patients with diabetic polyneuropathy with no difference in physical and mental composite scores (p > 0.05. The age of the patients, mean MRC sum score, arm disability scale score, leg disability scale score and mean INCAT sensory sum score correlated with scores in the SF-36 questionnaire (p < 0.01. The patients with higher scores of anxiety and depression had significantly worse health perception for all QoL domains, for both composite scores and for the total SF-36 score (p < 0.01. Both motor and sensory NCS parameters of the median nerve showed significant correlations with QoL scores (p < 0.05. Conclusion. Our results showed mild to moderate QoL impairment in the patients with diabetic polyneuropathy. HRQoL significantly correlated with the age of the patients, muscle strength, disability

  1. A prospective multi-centric open clinical trial of homeopathy in diabetic distal symmetric polyneuropathy.

    Science.gov (United States)

    Nayak, Chaturbhuja; Oberai, Praveen; Varanasi, Roja; Baig, Hafeezullah; Ch, Raveender; Reddy, G R C; Devi, Pratima; S, Bhubaneshwari; Singh, Vikram; Singh, V P; Singh, Hari; Shitanshu, Shashi Shekhar

    2013-04-01

    To evaluate homeopathic treatment in the management of diabetic distal symmetric polyneuropathy. A prospective multi-centric clinical observational study was carried out from October 2005 to September 2009 by Central Council for Research in Homeopathy (CCRH) (India) at its five institutes/units. Patients suffering from diabetes mellitus (DM) and presenting with symptoms of diabetic polyneuropathy (DPN) were screened, investigated and were enrolled in the study after fulfilling the inclusion and exclusion criteria. Patients were evaluated by the diabetic distal symmetric polyneuropathy symptom score (DDSPSS) developed by the Council. A total of 15 homeopathic medicines were identified after repertorizing the nosological symptoms and signs of the disease. The appropriate constitutional medicine was selected and prescribed in 30, 200 and 1 M potency on an individualized basis. Patients were followed up regularly for 12 months. Out of 336 patients (167 males and 169 females) enrolled in the study, 247 patients (123 males and 124 females) were analyzed. All patients who attended at least three follow-up appointments and baseline curve conduction studies were included in the analysis.). A statistically significant improvement in DDSPSS total score (p = 0.0001) was found at 12 months from baseline. Most objective measures did not show significant improvement. Lycopodium clavatum (n = 132), Phosphorus (n = 27) and Sulphur (n = 26) were the medicines most frequently prescribed. Adverse event of hypoglycaemia was observed in one patient only. This study suggests homeopathic medicines may be effective in managing the symptoms of DPN patients. Further studies should be controlled and include the quality of life (QOL) assessment. Copyright © 2013 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  2. Human Islet Amyloid Polypeptide

    DEFF Research Database (Denmark)

    Kosicka, Iga

    2014-01-01

    Diabetes mellitus type II is a metabolic disease affecting millions of people worldwide. The disease is associated with occurence of insoluble, fibrillar, protein aggregates in islets of Langerhans in the pancreas - islet amyloid. The main constituent of these protein fibers is the human islet...... of diabetes type II, while revealing the structure(s) of islet amyloid fibrils is necessary for potential design of therapeutic agents....

  3. Amyloid Fibril Solubility

    OpenAIRE

    Rizzi, L. G.; Auer, S.

    2015-01-01

    It is well established that amyloid fibril solubility is protein specific, but how solubility depends on the interactions between the fibril building blocks is not clear. Here we use a simple protein model and perform Monte Carlo simulations to directly measure the solubility of amyloid fibrils as a function of the interaction between the fibril building blocks. Our simulations confirms that the fibril solubility depends on the fibril thickness and that the relationship between the interactio...

  4. Diagnostic efficiency and treatment strategy in chronic axonal polyneuropathy

    NARCIS (Netherlands)

    Vrancken, A.F.J.E.

    2007-01-01

    Polyneuropathy is a common peripheral nerve disorder that often has a well known cause such as diabetes, chronic renal disease, alcohol abuse, vitamin deficiency, hypothyroidism, or use of toxic medication. Elderly people are more often affected, but the differentiation from signs of normal ageing

  5. Mechanisms of conduction block in immune-mediated polyneuropathies

    NARCIS (Netherlands)

    Straver, D.C.G.

    2013-01-01

    Multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyneuropathy (CIDP) are immune-mediated neuropathies. Despite treatment being available, patients suffer from disabling weakness of arm and leg muscles and fatigue. Pathogenesis of MMN and CIDP is unclear, but the development

  6. Lower extremity nerve decompression in painful diabetic polyneuropathy

    NARCIS (Netherlands)

    Macare van Maurik, A.F.

    2014-01-01

    The aim of the study was to evaluate the effect of surgical decompression of nerves in the lower extremity in patients with painful diabetic polyneuropathy (DPN). Influences on pain, tactile sensation, anatomical aspects of the tibial nerve and thickness of the flexor retinaculum, use of pain

  7. Muscle fiber conduction abnormalities in early diabetic polyneuropathy

    NARCIS (Netherlands)

    Meijer, J. W. G.; Lange, F.; Links, T. P.; van der Hoeven, J. H.

    Objective: Diabetic polyneuropathy (PNP) has been proposed to be a primary disorder of sensory nerves. At an early stage motor nerve conduction velocity (MNCV) and muscle strength remain preserved due to compensatory mechanisms (axonal sprouting, reinnervation). We evaluated the use of invasive

  8. Salinomycin-induced polyneuropathy in cats: Morphologic and epidemiologic data

    NARCIS (Netherlands)

    Linde-Sipman, J.S. van der; Inch, T.S.G.A.M. van den; Nes, J.J. van; Verhagen, H.; Kersten, J.G.T.M.; Beynen, A.C.; Plekkringa, R.

    1999-01-01

    In April 1996, an outbreak of toxic polyneuropathy in cats occurred in the Netherlands. All cats had been fed one of two brands of dry cat food from one manufacturer. Chemical analyses of these foods, stomach contents, and liver and kidney of affected cats revealed contamination with the ionophor

  9. {beta} - amyloid imaging probes

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jae Min [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    Imaging distribution of {beta} - amyloid plaques in Alzheimer's disease is very important for early and accurate diagnosis. Early trial of the {beta} -amyloid plaques includes using radiolabeled peptides which can be only applied for peripheral {beta} - amyloid plaques due to limited penetration through the blood brain barrier (BBB). Congo red or Chrysamine G derivatives were labeled with Tc-99m for imaging {beta} - amyloid plaques of Alzheimer patient's brain without success due to problem with BBB penetration. Thioflavin T derivatives gave breakthrough for {beta} - amyloid imaging in vivo, and a benzothiazole derivative [C-11]6-OH-BTA-1 brought a great success. Many other benzothiazole, benzoxazole, benzofuran, imidazopyridine, and styrylbenzene derivatives have been labeled with F-18 and I-123 to improve the imaging quality. However, [C-11]6-OH-BTA-1 still remains as the best. However, short half-life of C-11 is a limitation of wide distribution of this agent. So, it is still required to develop an Tc-99m, F-18 or I-123 labeled agent for {beta} - amyloid imaging agent.

  10. Dynamics of electrophysiological parameters of distal symmetric polyneuropathy in the course of pregnancy of women with type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    A. I. Poroshnichenko

    2015-01-01

    Full Text Available Objective of the study: assessment of clinical and electroneuromyographic (ENMG parameters of distal symmetric polyneuropathy during pregnancy.Materials and methods. 32 pregnant women with type I diabetes mellitus were examined. Signs of diabetic polyneuropathy (DPNP were revealed in 87.5 percent (n = 28 of patients. Duration of diabetes in patients with DPNP varied from 1 to 30 years (in average, 11.0 ± 6.4 years. Subjective (NSS scale and objective assessment (NDS scale of neuropathy symptoms, as well as the nerve conduction studies of the peroneal, tibial, and sural nerves were performed twice, on the 15–16 and 32–33 weeks of pregnancy.Results. Increase in subjective and objective symptoms of polyneuropathy along the pregnancy according to NSS and NDS scales (р < 0.05, as well as significant decrease of CMAP and SNAP amplitudes (р < 0.05 in the second half of pregnancy, indicating the progression of the DPNP. The most frequent pathological changes were observed in the peroneal and sural nerves.Conclusions. Pregnancy has an adverse effect on the course of the DPNP contributing to the axonal damage of peripheral nerves, progression of neurological impairment and aggravation of subjective neuropathic symptoms.

  11. High energy diets-induced metabolic and prediabetic painful polyneuropathy in rats.

    Directory of Open Access Journals (Sweden)

    Fang Xie

    Full Text Available To establish the role of the metabolic state in the pathogenesis of polyneuropathy, an age- and sex-matched, longitudinal study in rats fed high-fat and high-sucrose diets (HFSD or high-fat, high-sucrose and high-salt diets (HFSSD relative to controls was performed. Time courses of body weight, systolic blood pressure, fasting plasma glucose (FPG, insulin, free fatty acids (FFA, homeostasis model assessment-insulin resistance index (HOMA-IR, thermal and mechanical sensitivity and motor coordination were measured in parallel. Finally, large and small myelinated fibers (LMF, SMF as well as unmyelinated fibers (UMF in the sciatic nerves and ascending fibers in the spinal dorsal column were quantitatively assessed under electron microscopy. The results showed that early metabolic syndrome (hyperinsulinemia, dyslipidemia, and hypertension and prediabetic conditions (impaired fasting glucose could be induced by high energy diet, and these animals later developed painful polyneuropathy characterized by myelin breakdown and LMF loss in both peripheral and central nervous system. In contrast SMF and UMF in the sciatic nerves were changed little, in the same animals. Therefore the phenomenon that high energy diets induce bilateral mechanical, but not thermal, pain hypersensitivity is reflected by severe damage to LMF, but mild damage to SMF and UMF. Moreover, dietary sodium (high-salt deteriorates the neuropathic pathological process induced by high energy diets, but paradoxically high salt consumption, may reduce, at least temporarily, chronic pain perception in these animals.

  12. Sensory disturbance and polyneuropathy in rheumatoid arthritis patients with foot deformity

    Directory of Open Access Journals (Sweden)

    Ebru Karaca Umay

    2016-06-01

    Full Text Available Abstract Introduction Our aim in this study was to present the results of sensory evaluation tests and electrophysiological evaluations in rheumatoid arthritis (RA patients with foot deformity and to determine their relation with general health status and lower extremity functionality. Materials and methods Fifty-one patients with RA diagnosis and foot deformity were included in the study. Demographic and disease characteristics of the patients were recorded, and a detailed neurological examination was performed. Superficial sensation, pain, heat, vibration, and two-point discrimination sensation were evaluated in each foot, and their sum was used to determine the sensory deficits index (SDI of 0–10. The presence of polyneuropathy was evaluated with electrophysiological methods. The Health Assessment Questionnaire and mobility and walking subscales of the Arthritis Impact Measurement Scales-2 were used to assess general health status and lower extremity functionality, respectively. According to the sensory examination and electromyography results, patients were compared in terms of their general health status and lower extremity functional status. Results Sensory disturbance was detected in 39 patients (74% during the examination; however, 27 patients (52.9% had polyneuropathy determined electrophysiologically. In patients with sensory deficits, statistically significant deterioration was detected in general health and foot functionality, including mobility and walking, when compared to patients with a normal sensory evaluation. Conclusions Even in the presence of normal electrophysiological tests, sensory dysfunction alone seems to be associated with severe disability in general health status and foot functionality when compared to patients with a normal sensory examination.

  13. Sensory disturbance and polyneuropathy in rheumatoid arthritis patients with foot deformity.

    Science.gov (United States)

    Karaca Umay, Ebru; Gurcay, Eda; Karsli, Pinar Bora; Cakci, Aytul

    2016-01-01

    Our aim in this study was to present the results of sensory evaluation tests and electrophysiological evaluations in rheumatoid arthritis (RA) patients with foot deformity and to determine their relation with general health status and lower extremity functionality. Fifty-one patients with RA diagnosis and foot deformity were included in the study. Demographic and disease characteristics of the patients were recorded, and a detailed neurological examination was performed. Superficial sensation, pain, heat, vibration, and two-point discrimination sensation were evaluated in each foot, and their sum was used to determine the sensory deficits index (SDI) of 0-10. The presence of polyneuropathy was evaluated with electrophysiological methods. The Health Assessment Questionnaire and mobility and walking subscales of the Arthritis Impact Measurement Scales-2 were used to assess general health status and lower extremity functionality, respectively. According to the sensory examination and electromyography results, patients were compared in terms of their general health status and lower extremity functional status. Sensory disturbance was detected in 39 patients (74%) during the examination; however, 27 patients (52.9%) had polyneuropathy determined electrophysiologically. In patients with sensory deficits, statistically significant deterioration was detected in general health and foot functionality, including mobility and walking, when compared to patients with a normal sensory evaluation. Even in the presence of normal electrophysiological tests, sensory dysfunction alone seems to be associated with severe disability in general health status and foot functionality when compared to patients with a normal sensory examination. Copyright © 2015 Elsevier Editora Ltda. All rights reserved.

  14. High Energy Diets-Induced Metabolic and Prediabetic Painful Polyneuropathy in Rats

    Science.gov (United States)

    Hou, Jun-Feng; Jiao, Kai; Costigan, Michael; Chen, Jun

    2013-01-01

    To establish the role of the metabolic state in the pathogenesis of polyneuropathy, an age- and sex-matched, longitudinal study in rats fed high-fat and high-sucrose diets (HFSD) or high-fat, high-sucrose and high-salt diets (HFSSD) relative to controls was performed. Time courses of body weight, systolic blood pressure, fasting plasma glucose (FPG), insulin, free fatty acids (FFA), homeostasis model assessment-insulin resistance index (HOMA-IR), thermal and mechanical sensitivity and motor coordination were measured in parallel. Finally, large and small myelinated fibers (LMF, SMF) as well as unmyelinated fibers (UMF) in the sciatic nerves and ascending fibers in the spinal dorsal column were quantitatively assessed under electron microscopy. The results showed that early metabolic syndrome (hyperinsulinemia, dyslipidemia, and hypertension) and prediabetic conditions (impaired fasting glucose) could be induced by high energy diet, and these animals later developed painful polyneuropathy characterized by myelin breakdown and LMF loss in both peripheral and central nervous system. In contrast SMF and UMF in the sciatic nerves were changed little, in the same animals. Therefore the phenomenon that high energy diets induce bilateral mechanical, but not thermal, pain hypersensitivity is reflected by severe damage to LMF, but mild damage to SMF and UMF. Moreover, dietary sodium (high-salt) deteriorates the neuropathic pathological process induced by high energy diets, but paradoxically high salt consumption, may reduce, at least temporarily, chronic pain perception in these animals. PMID:23451227

  15. [Diabetic somatic polyneuropathy. Pathogenesis, clinical manifestations and therapeutic concepts].

    Science.gov (United States)

    Hilz, M J; Marthol, H; Neundörfer, B

    2000-06-01

    Diabetic polyneuropathy is the most frequent neuropathy in western countries. In Germany, there are 3.5 to 4 million diabetic patients. Diagnosis should rule out other polyneuropathies and assess two out of the five diagnostic criteria: neuropathic symptoms, neuropathic deficits, pathological nerve conduction studies, pathological quantitative sensory testing and pathological quantitative autonomic testing. So far, the pathophysiology of diabetic neuropathy remains to be fully understood. Among the various pathophysiological concepts are the Sorbitol-Myo-Inositol hypothesis attributing Myo-Inositol depletion to the accumulation of Sorbitol and Fructose, the concept of deficiency of essential fatty acids with reduced availability of gamma-linolenic-acid and prostanoids, the pseudohypoxia- and hypoxia-hypothesis attributing endothelial and axonal dysfunction and structural lesions to increased oxidative stress and free radical production. Obviously, the hyperglycemia induced generation of advanced glycation end products (AGEs) also contributes to structural dysfunctions and lesions. Elevated levels of circulating immune complexes and activated T-lymphocytes as well the identification of autoantibodies against vagus nerve or sympathetic ganglia support the concept of an immune mediated neuropathy. The reduction of neurotrophic factors such as nerve growth factor, neurotrophin-3 or insulin-like growth factors also seems to further diabetic neuropathy. The symmetrical, distally pronounced and predominantly sensory neuropathy is far more frequent than the symmetrical neuropathy with predominant motor weakness or the asymmetrical neuropathy. The painless neuropathy manifests with impaired light touch sensation, position sense, vibratory perception and diminished or absent ankle deep tendon reflexes. The painful sensory diabetic neuropathy primarily affects small nerve fibers and accounts for decreased temperature perception and paresthesias. The proximal, diabetic

  16. Familial amyloidotic polyneuropathy: current and emerging treatment options for transthyretin-mediated amyloidosis

    Directory of Open Access Journals (Sweden)

    Hund E

    2012-06-01

    Full Text Available Ernst HundDepartment of Neurology, University of Heidelberg, Heidelberg, GermanyAbstract: Transthyretin familial amyloid polyneuropathy (TTR-FAP is a fatal clinical disorder characterized by extracellular deposition of abnormal fibrils derived from misfolded, normally soluble transthyretin (TTR molecules. The disease is most commonly caused by a point mutation within the TTR gene inherited in an autosomal dominant fashion. Over 100 of such mutations have been identified, leading to destabilization of the physiological TTR tetramer. As a result, many monomers originate with a tendency for spontaneous conformational changes and self-aggregation. The main clinical feature of TTR-FAP is progressive sensorimotor and autonomic neuropathy. In the beginning, this polyneuropathy predominantly involves small unmyelinated nerve fibers with the result of dissociated sensory loss disproportionately affecting sensation of pain and temperature. Autonomic neuropathy typically accompanies sensory deficits early in the disease course. The symptoms include orthostatic hypotension, constipation alternating with diarrhea, erectile dysfunction, anhydrosis, and urinary retention or incontinence. Later, involvement of motor fibers causes rapidly progressive weakness and gait disturbances. In addition to the peripheral nervous system, the heart and the gut are frequently affected. Onset of symptoms is bimodal, with one peak at age 33 years (early onset and another distinct peak in the sixth decade of life (late onset. The course of TTR-FAP is uniformly progressive and fatal. Death occurs an average of 10.8 years after the onset of symptoms in Portuguese patients, and 7.3 years in late-onset Japanese patients. Common causes include cachexia, cardiac failure, arrhythmia, and secondary infections. Liver transplantation is the standard therapy for patients who are in a clinical condition good enough to tolerate this intervention because it stops progression of neuropathy by

  17. Development, appraisal, validation and implementation of a consensus protocol for the assessment of cerebral amyloid angiopathy in post-mortem brain tissue

    Science.gov (United States)

    Love, Seth; Chalmers, Katy; Ince, Paul; Esiri, Margaret; Attems, Johannes; Jellinger, Kurt; Yamada, Masahito; McCarron, Mark; Minett, Thais; Matthews, Fiona; Greenberg, Steven; Mann, David; Kehoe, Patrick Gavin

    2014-01-01

    In a collaboration involving 11 groups with research interests in cerebral amyloid angiopathy (CAA), we used a two-stage process to develop and in turn validate a new consensus protocol and scoring scheme for the assessment of CAA and associated vasculopathic abnormalities in post-mortem brain tissue. Stage one used an iterative Delphi-style survey to develop the consensus protocol. The resultant scoring scheme was tested on a series of digital images and paraffin sections that were circulated blind to a number of scorers. The scoring scheme and choice of staining methods were refined by open-forum discussion. The agreed protocol scored parenchymal and meningeal CAA on a 0-3 scale, capillary CAA as present/absent and vasculopathy on 0-2 scale, in the 4 cortical lobes that were scored separately. A further assessment involving three centres was then undertaken. Neuropathologists in three centres (Bristol, Oxford and Sheffield) independently scored sections from 75 cases (25 from each centre) and high inter-rater reliability was demonstrated. Stage two used the results of the three-centre assessment to validate the protocol by investigating previously described associations between APOE genotype (previously determined), and both CAA and vasculopathy. Association of capillary CAA with or without arteriolar CAA with APOE ε4 was confirmed. However APOE ε2 was also found to be a strong risk factor for the development of CAA, not only in AD but also in elderly non-demented controls. Further validation of this protocol and scoring scheme is encouraged, to aid its wider adoption to facilitate collaborative and replication studies of CAA. PMID:24754000

  18. Erratum: Development, appraisal, validation and implementation of a consensus protocol for the assessment of cerebral amyloid angiopathy in post-mortem brain tissue.

    Science.gov (United States)

    Love, Seth; Chalmers, Katy; Ince, Paul; Esiri, Margaret; Attems, Johannes; Kalaria, Raj; Jellinger, Kurt; Yamada, Masahito; McCarron, Mark; Minett, Thais; Matthews, Fiona; Greenberg, Steven; Mann, David; Kehoe, Patrick Gavin

    2015-01-01

    In a collaboration involving 11 groups with research interests in cerebral amyloid angiopathy (CAA), we used a two-stage process to develop and in turn validate a new consensus protocol and scoring scheme for the assessment of CAA and associated vasculopathic abnormalities in post-mortem brain tissue. Stage one used an iterative Delphi-style survey to develop the consensus protocol. The resultant scoring scheme was tested on a series of digital images and paraffin sections that were circulated blind to a number of scorers. The scoring scheme and choice of staining methods were refined by open-forum discussion. The agreed protocol scored parenchymal and meningeal CAA on a 0-3 scale, capillary CAA as present/absent and vasculopathy on 0-2 scale, in the 4 cortical lobes that were scored separately. A further assessment involving three centres was then undertaken. Neuropathologists in three centres (Bristol, Oxford and Sheffield) independently scored sections from 75 cases (25 from each centre) and high inter-rater reliability was demonstrated. Stage two used the results of the three-centre assessment to validate the protocol by investigating previously described associations between APOE genotype (previously determined), and both CAA and vasculopathy. Association of capillary CAA with or without arteriolar CAA with APOE ε4 was confirmed. However APOE ε2 was also found to be a strong risk factor for the development of CAA, not only in AD but also in elderly non-demented controls. Further validation of this protocol and scoring scheme is encouraged, to aid its wider adoption to facilitate collaborative and replication studies of CAA.[This corrects the article on p. 19 in vol. 3, PMID: 24754000.].

  19. Undiagnosed Small-Fiber Polyneuropathy - Is it a Component of Gulf-War Illness

    Science.gov (United States)

    2013-07-01

    Research Program. Small-fiber polyneuropathy (SFPN) subjects from the neurology practice at Massachusetts General Hospital were also invited to...in the journal PAIN®. A related study of juvenile-onset small-fiber polyneuropathy , to which support by the Gulf War Illness Research Program was...that small-fiber polyneuropathy underlies some illnesses currently labeled as fibromyalgia. Pain. 2013 Jun 5. doi:pii: S0304-3959(13)00294-7. 10.1016

  20. Undiagnosed Small-Fiber Polyneuropathy: Is it a Component of Gulf War Illness?

    Science.gov (United States)

    2014-09-01

    journal PAIN® [13]. A related study of juvenile-onset small-fiber polyneuropathy , to which support by the Gulf War Illness Research Program was...Herzog ZD, Downs HM, Klein MM. Objective evidence that small-fiber polyneuropathy underlies some illnesses currently labeled as fibromyalgia. Pain... polyneuropathy done in our laboratory. The Gulf War Illness Research Program is credited with partial support of this study because several of the adult

  1. Amyloid Beta Mediates Memory Formation

    Science.gov (United States)

    Garcia-Osta, Ana; Alberini, Cristina M.

    2009-01-01

    The amyloid precursor protein (APP) undergoes sequential cleavages to generate various polypeptides, including the amyloid [beta] (1-42) peptide (A[beta][1-42]), which is believed to play a major role in amyloid plaque formation in Alzheimer's disease (AD). Here we provide evidence that, in contrast with its pathological role when accumulated,…

  2. DIABETIC POLYNEUROPATHY: CURRENT APPROACHES TO DIAGNOSIS AND PATHOGENETIC THERAPY

    Directory of Open Access Journals (Sweden)

    O. S. Levin

    2013-01-01

    Full Text Available The paper considers the current views of the prevalence, clinical picture, approaches to the diagnosis and treatment of one of the most commonneurological complications of diabetes mellitus – diabetic polyneuropathy, and both its somatic and autonomous manifestations. Neuropathy ismost common in diabetic patients and its clinical forms reflect the severe course of diabetes mellitus and serve as an unfavorable prognostic signthat is associated with an approximately 5-fold increase in mortality. At the same time, the timely detection and adequate correction of the manifestations of neuropathy may substantially improve quality of life in the patients. The possibilities of pathogenetic therapy for diabetic polyneuropathy associated mainly with the use of benfotiamine and alpha-lipoic acid, as well as symptomatic therapy for its individual manifestationsare considered.

  3. Peripheral polyneuropathy after bariatric surgery for morbid obesity

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    I-Ching Lin

    2011-01-01

    Full Text Available A patient with peripheral polyneuropathy after bariatric surgery for morbid obesity is reported. She suffered from frequent episodes of vomiting and abdominal pain after surgery. Muscle weakness in her lower limbs developed 5 months later and she experienced difficulty in walking and standing. Wrist drop, foot drop, and marked distal limb muscle atrophy were found bilaterally. Electromyography showed the presence of sensorimotor axonal polyneuropathy. Nutritional deficiencies may play an important role in pathogenesis. This uncommon neurological complication might be due to rapid weight loss and vitamin deficiency. Physicians who take care for patients after bariatric surgery should have a high index of awareness for the neurologic complications, and routine vitamin supplementation might be useful for these patients.

  4. Amyloid positron emission tomography in sporadic cerebral amyloid angiopathy: A systematic critical update

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    Karim Farid

    2017-01-01

    . A total of six small-scale studies have addressed (or reported data useful to address the diagnostic utility of late-phase amyloid PET imaging in CAA, and one additional study dealt with early PiB images as a proxy of brain perfusion. Across these studies, amyloid PET imaging has definite diagnostic utility (currently tested only in probable CAA: it helps rule out CAA if negative, whether compared to healthy controls or to hypertensive deep ICH controls. If positive, however, differentiation from underlying incipient Alzheimer's disease (AD can be challenging and so far, no approach (regional values, ratios, visual assessment seems sufficient and specific enough, although early PiB data seem to hold promise. Based on the available evidence reviewed, we suggest a tentative diagnostic flow algorithm for amyloid-PET use in the clinical setting of suspected CAA, combining early- and late-phase PiB-PET images. We also identified ten mechanistic amyloid-PET studies providing early but promising proof-of-concept data on CAA pathophysiology and its various manifestations including key MRI lesions, cognitive impairment and large scale brain alterations. Key open questions that should be addressed in future studies of amyloid-PET imaging in CAA are identified and highlighted.

  5. Is Regenerative Medicine Ready for Prime Time in Diabetic Polyneuropathy?

    OpenAIRE

    Himeno, Tatsuhito; Kamiya, Hideki; Nakamura, Jiro

    2018-01-01

    Purpose of Review After a prolonged warm-up period of basic research, several modalities of cell replacement therapies are under development for diseases with no available cure. Diabetic polyneuropathy (DPN) is one of the most prevalent chronic diabetes complications that causes sensorimotor dysfunction, subsequent high risks for lower limb amputations, and high mortality. Currently, no disease modifying therapy exists for DPN. Recent Findings Several types of well-documented stem/progenitor ...

  6. [Electron microscopic findings in a polyneuropathy complicating panarteritis nodosa].

    Science.gov (United States)

    Backwinkel, K P; Feyerabend, H; Sitzer, G; Richter, H W; Themann, H

    1976-01-01

    Electromicroscopial changes were observed in arterioles, nerves, and striated skeleton muscle cells in a case of clinically and histologically definite polyarteritis nodosa with polyneuropathy. Inflammatory infiltrates were found in and around arteriolar walls; motor nerves were partly demarkated and presynaptic motor endplates were degenerated. The myofibrills of skeleton muscle cells showed a disorganization that is regarded as the morphological substrate for the clinically observed muscular weakness in this case.

  7. Lower urinary tract dysfunction in critical illness polyneuropathy.

    Science.gov (United States)

    Reitz, André

    2013-01-01

    Critical illness polyneuropathy is a frequent complication of critical illness in intensive care units. Reports on autonomic systems like lower urinary tract and bowel functions in patients with CIP are not available in medical literature. This study performed during primary rehabilitation of patients with critical illness polyneuropathy explores if sensory and motor pathways controlling the lower urinary tract function are affected from the disease. Neurourological examinations, urodynamics, electromyography and lower urinary tract imaging were performed in 28 patients with critical illness polyneuropathy. Sacral sensation was impaired in 1 patient (4%). Sacral reflexes were absent in 8 patients (30%). Anal sphincter resting tone was reduced in 3 (12%), anal sphincter voluntary contraction was absent or reduced in 8 patients (30%). Urodynamic findings were detrusor overactivity and detrusor overactivity incontinence in 9 (37.5%), incomplete voiding in 8 (30%), abnormal sphincter activity in 4 (16%), abnormal bladder sensation in 4 (16%) and detrusor acontractility in 2 patients (8.3%). Morphological abnormalities of the lower urinary tract had 10 patients (41.6%). Sensory and motor pathways controlling the lower urinary tract might be affected from CIP. During urodynamics dysfunctions of the storage as well as the voiding phase were found. Morphological lower urinary tract abnormalities were common.

  8. [Thallium poisoning induced polyneuropathy--clinical and electrophysiological data].

    Science.gov (United States)

    Lukács, Miklós

    2003-11-20

    The aim of the study was the electrophysiological investigation of thallium induced polyneuropathy. Beyond the rarity of the illness, the motivation of this work was the possibility of following up the pattern of neuronal damage. Thallium is one of the most toxic heavy metal and its wide use increases the chance of chronic or accidental acute poisoning. The entero-hepatic circulation makes the accumulation of this toxic agent in tissues possible, mostly in neurons, in the epithelial cells of the digestive tract, in the germinative cells of the skin and testicles. In addition to alopecia and digestive complaints, the clinical picture of thallium poisoning is dominated by neurological signs. Severe axonal polyneuropathy develops in almost all cases, with further damage to the retina and impairment of cognitive functions being not unusual. The diagnosis is confirmed by finding high levels of thallium in body fluids, especially in saliva and urine. Electrophysiological examination of our accidentally poisoned patient revealed severe, sensory-motor, predominant motor axonal polyneuropathy and pointed out some aspects of the pattern of neurotoxic process: the initially distal lesion, the dying-back course and the capacity for regeneration. Because thallium has the same molecular targets as potassium ion thus impairing the energetical supply of the nerve cell, the most effective treatment is carefully loading with potassium. If recognized and treated early, thallium poisoning has a favourable prognosis.

  9. Heterogeneity of Polyneuropathy Associated with Anti-MAG Antibodies

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    Laurent Magy

    2015-01-01

    Full Text Available Polyneuropathy associated with IgM monoclonal gammopathy and anti-myelin associated glycoprotein (MAG antibodies is an immune-mediated demyelinating neuropathy. The pathophysiology of this condition is likely to involve anti-MAG antibody deposition on myelin sheaths of the peripheral nerves and it is supposed to be distinct from chronic inflammatory demyelinating neuropathy (CIDP, another immune-mediated demyelinating peripheral neuropathy. In this series, we have retrospectively reviewed clinical and laboratory findings from 60 patients with polyneuropathy, IgM gammopathy, and anti-MAG antibodies. We found that the clinical picture in these patients is highly variable suggesting a direct link between the monoclonal gammopathy and the neuropathy. Conversely, one-third of patients had a CIDP-like phenotype on electrodiagnostic testing and this was correlated with a low titer of anti-MAG antibodies and the absence of widening of myelin lamellae. Our data suggest that polyneuropathy associated with anti-MAG antibodies is less homogeneous than previously said and that the pathophysiology of the condition is likely to be heterogeneous as well with the self-antigen being MAG in most of the patients but possibly being another component of myelin in the others.

  10. Diagnostic performance and prognostic value of extravascular retention of I-123-labeled serum amyloid P component in systemic amyloidosis

    NARCIS (Netherlands)

    Hazenberg, Bouke P. C.; van Rijswijk, Martin H.; Lub-de Hooge, Marjolijn N.; Vellenga, Edo; Haagsma, Elizabeth B.; Posthumus, Marcel D.; Jager, Pieter L.

    Serum amyloid P component (SAP) binds to amyloid.I-123-SAP scintigraphy is used to evaluate the extent and distribution of amyloid in systemic amyloidosis and has great clinical value in the detection of systemic amyloidosis. The aim of the study was to assess during scintigraphy the diagnostic

  11. Electrodiagnostic studies in presumptive primary hypothyroidism and polyneuropathy in dogs with reevaluation during hormone replacement therapy.

    Science.gov (United States)

    Giza, Elżbieta Gabriela; Płonek, Marta; Nicpoń, Józef Marian; Wrzosek, Marcin Adam

    2016-05-21

    Peripheral neuropathy is the most common neurological manifestation of canine hypothyroidism. Data concerning electrodiagnostic studies in hypothyroid associated polyneuropathy in dogs are very limited and usually lack a reevaluation after hormone replacement therapy. The objective of this study was to perform a detailed, retrospective analysis of electromyographic (EMG), motor nerve conduction velocity (MNCV), F-wave and brainstem auditory evoked response (BAER) findings in 24 dogs with presumptive primary hypothyroidism and polyneuropathy with a comparison of the results before and after initiation of levothyroxine treatment with the assessment of the clinical outcome. The results obtained from hypothyroid dogs showed a significant reduction in MNCV at a proximal-distal and middle-distal stimulation, decreased amplitudes of compound muscle action potentials (CMAP), an increased CMAP duration and a prolonged distal latency prior to treatment. Fifty percent of the dogs had an increased F-wave latency. A normal BAER recording was found in 78 % of the hypothyroid patients without vestibular impairment. Bilaterally increased peak V latencies and increased interpeak I-V latencies were found in the remaining individuals. Dogs with concurrent vestibular impairment had ipsilaterally increased peak latencies with normal interpeak latencies and decreased amplitudes of wave I and II. A comparison of the findings before and after 2 months of treatment revealed a decrease in the pathological activity on EMG, an improvement of proximal, middle and distal CMAP amplitudes and an increase in the proximal-distal conduction velocity in all dogs. F-wave latency improved in 38 % of dogs. The BAER reexamination revealed a persistent prolongation of peak I, II, III and V latencies and decreased wave I amplitude on the affected side in all dogs manifesting vestibular signs. Conversely, in dogs without vestibular signs, the peak V and interpeak I-V latencies decreased to normal values

  12. Intratubular amyloid in light chain cast nephropathy is a risk factor for systemic light chain amyloidosis.

    Science.gov (United States)

    Gibier, Jean-Baptiste; Gnemmi, Viviane; Glowacki, François; Boyle, Eileen M; Lopez, Benjamin; MacNamara, Evelyne; Hoffmann, Maxime; Azar, Raymond; Guincestre, Thomas; Bourdon, Franck; Copin, Marie-Christine; Buob, David

    2017-10-20

    Light chain cast nephropathy is the most common form of kidney disease in patients with multiple myeloma. Light chain casts may occasionally show amyloid staining properties, that is, green birefringence after Congo red staining. The frequency and clinical significance of this intratubular amyloid are poorly understood. Here, we retrospectively assessed the clinicopathological features of 60 patients with histologically proven light chain cast nephropathy with a specific emphasis on intratubular amyloid, especially, its association with extrarenal systemic light chain amyloidosis. We found intratubular amyloid in 17 cases (17/60, 28%) and it was more frequent in patients with λ light chain gammopathy (13/17 in the 'intratubular amyloid' group vs 19/43 in the 'no intratubular amyloid' group, P=0.02). Pathological examination of extrarenal specimens showed that intratubular amyloid was significantly associated with the occurrence of systemic light chain amyloidosis (5/13 in the 'intratubular amyloid' group vs 0/30 in the 'no intratubular amyloid' group, P=0.001). Our results indicate that first, intratubular amyloid is not a rare finding in kidney biopsies of patients with light chain cast nephropathy, and, second, it reflects an amyloidogenic capacity of light chains that can manifest as systemic light chain amyloidosis. Thus, intratubular amyloid should be systematically screened for in kidney biopsies from patients with light chain cast nephropathy and, if detected, should prompt a work-up for associated systemic light chain amyloidosis.Modern Pathology advance online publication, 20 October 2017; doi:10.1038/modpathol.2017.124.

  13. Fish β-parvalbumin acquires allergenic properties by amyloid assembly.

    Science.gov (United States)

    Martínez, Javier; Sánchez, Rosa; Castellanos, Milagros; Fernández-Escamilla, Ana M; Vázquez-Cortés, Sonia; Fernández-Rivas, Montserrat; Gasset, María

    2015-01-01

    Amyloids are highly cross-β-sheet-rich aggregated states that confer protease resistance, membrane activity and multivalence properties to proteins, all essential features for the undesired preservation of food proteins transiting the gastrointestinal tract and causing type I allergy. Amyloid propensity of β-parvalbumin, the major fish allergen, was theoretically analysed and assayed under gastrointestinal-relevant conditions using the binding of thioflavin T, the formation of sodium dodecyl sulphate- (SDS-) resistant aggregates, circular dichroism spectroscopy and atomic force microscopy fibril imaging. Impact of amyloid aggregates on allergenicity was assessed with dot blot. Sequences of β-parvalbumin from species with commercial value contain several adhesive hexapeptides capable of driving amyloid formation. Using Atlantic cod β-parvalbumin (rGad m 1) displaying high IgE cross-reactivity, we found that formation of amyloid fibres under simulated gastrointestinal conditions accounts for the resistance to acid and neutral proteases, for the presence of membrane active species under gastrointestinal relevant conditions and for the IgE-recognition in the sera of allergic patients. Incorporation of the anti-amyloid compound epigallocatechin gallate prevents rGad m 1 fibrillation, facilitates its protease digestion and impairs its recognition by IgE. the formation of amyloid by rGad m 1 explains its degradation resistance, its facilitated passage across the intestinal epithelial barrier and its epitope architecture as allergen.

  14. The Prevalence and Severity of Autonomic Dysfunction in Chronic Inflammatory Demyelinating Polyneuropathy.

    Science.gov (United States)

    Pasangulapati, Suresh Babu; Murthy, T V; Sivadasan, Ajith; Gideon, L Rynjah; Prabhakar, A T; Sanjith, Aaron; Mathew, Vivek; Alexander, Mathew

    2017-01-01

    In chronic inflammatory demyelinating polyneuropathy (CIDP), emphasis has been on motor disabilities, and autonomic dysfunction in these patients has not been addressed systematically. Autonomic function was prospectively analyzed in 38 patients with CIDP. Quantitative autonomic function testing was done using Finometer ® PRO and severity of adrenergic and cardiovagal dysfunction graded according to composite autonomic severity score and sudomotor dysfunction assessed using sympathetic skin response. Thirty-four (89%) patients had features of autonomic dysfunction. Thirty-three (86%) patients had cardiovagal dysfunction, 21 (55%) had adrenergic dysfunction, and 24 (63%) had sudomotor dysfunction. Autonomic dysfunction was mild to moderate in the majority (86%). Autonomic dysfunction in CIDP is underreported and potentially amenable to therapy. Our cohort had a high proportion of adrenergic dysfunction compared to previous studies.

  15. Changes in spatiotemporal gait parameters following intravenous immunoglobulin treatment for chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Vo, Mary L; Chin, Russell L; Miranda, Caroline; Latov, Norman

    2017-10-01

    Gait impairment is a common presenting symptom in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, gait parameters have not previously been evaluated in detail as potential independent outcome measures. We prospectively measured changes in spatiotemporal gait parameters of 20 patients with CIDP at baseline and following treatment with intravenous immunoglobulin (IVIG), using GAITRite® a computerized walkway system with embedded sensors. Overall, study patients showed significant improvements in gait velocity, cadence, stride length, double support time, stance phase, and swing phase following IVIG treatment. Mean changes in velocity, stance phase, and swing phase, exhibited the greatest statistical significance among the subgroup that exhibited clinically meaningful improvement in Inflammatory Neuropathy Cause and Treatment disability score, Medical Research Council sum score, and grip strength. Assessment of gait parameters, in particular velocity, step phase and swing phase, is a potentially sensitive outcome measure for evaluating treatment response in CIDP. Muscle Nerve 56: 732-736, 2017. © 2017 Wiley Periodicals, Inc.

  16. ISOKINETIC TESTING OF ANKLE MUSCULAR STRENGTH AND PROPRIOCEPTION, BALANCE AND NERVE CONDUCTION IN PATIENTS WITH POLYNEUROPATHY

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    Ashraf Darwesh

    2017-12-01

    Full Text Available Background: Polyneuropathy is one of the most common chronic complications associated with diabetes mellitus, it is a damage to the peripheral nerves and manifested by signs and symptoms as numbness, irritation, and pain in the upper and lower limbs. This study aimed to evaluate muscular performance and proprioception at the ankle in diabetic neuropathic patients with quantitative and standardized tools and correlate these findings with those of sural nerve conduction velocity (sural NCV and amplitude. Methods: Fifteen male patients with diabetic neuropathy participated in this study, with age ranged from 40 to 55 years, and fifteen age-matched healthy subjects participated as a control group. Biodex Isokinetic System was used to assess the strength of ankle dorsiflexors and planter flexors and ankle reposition accuracy. Berg balance test was used to assess balance. Sural nerve conduction velocity (NCV and amplitude were examined by diabetic polyneuropathy check (DPN-check device. Results: The results showed a significant decrease in the mean peak torque values of the plantar flexors and dorsiflexors and a significant increase in the reposition error in the diabetic neuropathic group (p=0.0001. The results also revealed a significant decrease in the mean values of the Berg balance scores in diabetic neuropathy group (p=0.0001. Sural NCV and amplitude tests revealed abnormal values (p<0.05. Conclusion: It was concluded that the isokinetic system is an objective and sensitive tool to detect the motor and sensory changes of the diabetic neuropathic patients, also an examination by DPN-check device help in the determination of the severity of the disease. Moreover, it can be concluded that there are strong correlations between duration of diabetes and sural nerve NCV and amplitude and the peak torque of the muscles around the ankle.

  17. Homocysteine metabolism is associated with cerebrospinal fluid levels of soluble amyloid precursor protein and amyloid beta.

    Science.gov (United States)

    Oikonomidi, Aikaterini; Lewczuk, Piotr; Kornhuber, Johannes; Smulders, Yvo; Linnebank, Michael; Semmler, Alexander; Popp, Julius

    2016-10-01

    Disturbed homocysteine metabolism may contribute to amyloidogenesis by modulating the amyloid precursor protein (APP) production and processing. The objective of this study was to investigate the relationships between cerebral amyloid production and both blood and cerebrospinal fluid (CSF) markers of the homocysteine metabolism. We assessed CSF concentrations of soluble APPα, soluble APPβ, and amyloid β1-42 (Aβ1-42), as well as plasma levels of homocysteine (Hcys), total vitamin B12, and folate, and CSF concentrations of homocysteine (Hcys-CSF), 5-methyltetrahydrofolate (5-MTHF), S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH) in 59 subjects with normal cognition. Linear regression analyses were performed to assess associations between homocysteine metabolism parameters and amyloid production. The study was approved by the Ethical Committee of the University of Bonn. After controlling for age, gender, APOEe4 status, and albumin ratio (Qalb), higher Aβ1-42 CSF levels were associated with high Hcys and low vitamin B12 plasma levels as well as with high Hcys, high SAH, and low 5-MTHF CSF levels. Higher CSF concentrations of sAPPα and sAPPβ were associated with high SAH levels. The results suggest that disturbed homocysteine metabolism is related to increased CSF levels of sAPP forms and Aβ1-42, and may contribute to the accumulation of amyloid pathology in the brain. Disturbed homocysteine metabolism may contribute to amyloidogenesis by modulating the amyloid precursor protein (APP) production and processing. We found associations between CSF levels of soluble APP forms and Aβ1-42, and markers of the homocysteine metabolism in both plasma and CSF in adults with normal cognition. Disturbed homocysteine metabolism may represent a target for preventive and early disease-modifying interventions in Alzheimer's disease. © 2016 International Society for Neurochemistry.

  18. Neuromuscular ultrasound in polyneuropathies and motor neuron disease.

    Science.gov (United States)

    Hobson-Webb, Lisa D

    2013-06-01

    Current standards for diagnosing polyneuropathies (PN) and motor neuron disease (MND) sometimes lack early sensitivity and result in delayed diagnosis and treatment. Neuromuscular ultrasound (NMUS), already established in the diagnosis of entrapment neuropathies, may offer another means of diagnosis and monitoring response to therapy. This review of current evidence discusses diffuse nerve hypertrophy in hereditary demyelinating neuropathies, multifocal nerve enlargement in acquired demyelinating PN and the lack of readily apparent structural change in axonal neuropathies. NMUS detection of fasciculations and muscular change in MND is also reviewed, along with the need for further research to better define the role of nerve imaging in patients with PN. Copyright © 2013 Wiley Periodicals, Inc.

  19. [Critical illness polyneuropathy and myopathy as neurological complications of sepsis].

    Science.gov (United States)

    Kollmar, R

    2016-03-01

    Intensive care unit acquired weakness (ICUAW) is a frequent and severe complication of intensive care management. Within ICUAW critical illness polyneuropathy (CIP) and myopathy (CIM) can be differentiated. The major symptom of ICUAW is progressive quadriparesis, which makes weaning from the respirator more difficult, can appear early after admission to an ICU and can often be detected several months after discharge from the ICU. The pathophysiology of ICUAW is multifactorial and complex. Potential therapeutic approaches are the early and sufficient therapy of mulitorgan dysfunction, optimal control of glucose levels as well as early and intensive physiotherapy. This review article discusses the data on incidence, pathophysiology, diagnostic approaches and prognosis of ICUAW.

  20. Urinary 2,5-hexanedione excretion in cryptogenic polyneuropathy compared to the general Swedish population

    OpenAIRE

    Persson, Bodil; Vrethem, Magnus; Murgia, Nicola; Lindh, Jonas; Hallsten, Anna-Lena; Fredrikson, Mats; Tondel, Martin

    2013-01-01

    Background 2,5-hexanedione (2,5-HD) is the main neurotoxic metabolite of methyl-n-butyl ketone (MBK) and n-hexane, and known to cause polyneuropathy. The aim of our study was to compare the urinary levels of 2,5-HD between cases with cryptogenic polyneuropathy and the general Swedish population, and to elucidate the role of certain external factors. Methods Morning urine samples were collected from 114 cases with cryptogenic polyneuropathy (77 men and 37 women) and 227 referents (110 men and ...

  1. Functional outcomes and efficiency of rehabilitation in a national cohort of patients with Guillain-Barré syndrome and other inflammatory polyneuropathies.

    Directory of Open Access Journals (Sweden)

    Roxana Alexandrescu

    Full Text Available To describe functional outcomes, care needs and cost-efficiency of hospital rehabilitation for a UK cohort of inpatients with complex rehabilitation needs arising from inflammatory polyneuropathies.186 patients consecutively admitted to specialist neurorehabilitation centres in England with Guillain-Barré Syndrome (n = 118 (63.4% or other inflammatory polyneuropathies, including chronic inflammatory demyelinating polyneuropathy (n = 15 (8.1% or critical illness neuropathy (n = 32 (17.2%.Cohort analysis of data from the UK Rehabilitation Outcomes Collaborative national clinical dataset. Outcome measures include the UK Functional Assessment Measure, Northwick Park Dependency Score (NPDS and Care Needs Assessment (NPCNA. Patients were analysed in three groups of dependency based on their admission NPDS score: 'low' (NPDS<10, 'medium' (NPDS 10-24 and 'high' (NPDS ≥ 25. Cost-efficiency was measured as the time taken to offset the cost of rehabilitation by savings in NPCNA-estimated costs of on-going care in the community.The mean rehabilitation length of stay was 72.2 (sd = 66.6 days. Significant differences were seen between the diagnostic groups on admission, but all showed significant improvements between admission and discharge, in both motor and cognitive function (p<0.0001. Patients who were highly dependent on admission had the longest lengths of stay (mean 97.0 (SD 79.0 days, but also showed the greatest reduction in on-going care costs (£1049 per week (SD £994, so that overall they were the most cost-efficient to treat.Patients with polyneuropathies have both physical and cognitive disabilities that are amenable to change with rehabilitation, resulting in significant reduction in on-going care-costs, especially for highly dependent patients.

  2. Progressive cerebellar atrophy and polyneuropathy: expanding the spectrum of PNKP mutations

    NARCIS (Netherlands)

    Poulton, C.; Oegema, R.; Heijsman, D.; Hoogeboom, J.; Schot, R.; Stroink, H.; Willemsen, M.A.A.P.; Verheijen, F.W.; Spek, P. van der; Kremer, A.; Mancini, G.M.S.

    2013-01-01

    We present a neurodegenerative disorder starting in early childhood of two brothers consisting of severe progressive polyneuropathy, severe progressive cerebellar atrophy, microcephaly, mild epilepsy, and intellectual disability. The cause of this rare syndrome was found to be a homozygous mutation

  3. Clinical diagnosis of distal diabetic polyneuropathy using neurological examination scores: correlation with nerve conduction studies

    Directory of Open Access Journals (Sweden)

    Shereen R Kamel

    2015-01-01

    Conclusion Neurological examination scores can detect and grade neuropathy in the majority of cases. However, NCS was accurate for detection of diabetic sensorimotor polyneuropathy, especially for the subclinical neuropathies.

  4. 2 SISTERS WITH MENTAL-RETARDATION, CATARACT, ATAXIA, PROGRESSIVE HEARING-LOSS, AND POLYNEUROPATHY

    NARCIS (Netherlands)

    BEGEER, JH; SCHOLTE, FA; VANESSEN, AJ

    1991-01-01

    Two sisters are described with a disorder characterised by mental retardation, congenital cataract, progressive spinocerebellar ataxia, sensorineural deafness, and signs of peripheral neuropathy. Progressive hearing loss, ataxia, and polyneuropathy became evident in the third decade. The

  5. Treatment with α-Lipoic Acid over 16 Weeks in Type 2 Diabetic Patients with Symptomatic Polyneuropathy Who Responded to Initial 4-Week High-Dose Loading

    Science.gov (United States)

    Garcia-Alcala, Hector; Santos Vichido, Celia Isabel; Islas Macedo, Silverio; Genestier-Tamborero, Christelle Nathalie; Minutti-Palacios, Marissa; Hirales Tamez, Omara; García, Carlos; Ziegler, Dan

    2015-01-01

    Effective treatment of diabetic sensorimotor polyneuropathy remains a challenge. To assess the efficacy and safety of α-lipoic acid (ALA) over 20 weeks, we conducted a multicenter randomized withdrawal open-label study, in which 45 patients with type 2 diabetes and symptomatic polyneuropathy were initially treated with ALA (600 mg tid) for 4 weeks (phase 1). Subsequently, responders were randomized to receive ALA (600 mg qd; n = 16) or to ALA withdrawal (n = 17) for 16 weeks (phase 2). During phase 1, the Total Symptom Score (TSS) decreased from 8.9 ± 1.8 points to 3.46 ± 2.0 points. During phase 2, TSS improved from 3.7 ± 1.9 points to 2.5 ± 2.5 points in the ALA treated group (p < 0.05) and remained unchanged in the ALA withdrawal group. The use of analgesic rescue medication was higher in the ALA withdrawal group than ALA treated group (p < 0.05). In conclusion, in type 2 diabetic patients with symptomatic polyneuropathy who responded to initial 4-week high-dose (600 mg tid) administration of ALA, subsequent treatment with ALA (600 mg qd) over 16 weeks improved neuropathic symptoms, whereas ALA withdrawal was associated with a higher use of rescue analgesic drugs. This trial is registered with ClinicalTrials.gov Identifier: NCT02439879. PMID:26345602

  6. Treatment with α-Lipoic Acid over 16 Weeks in Type 2 Diabetic Patients with Symptomatic Polyneuropathy Who Responded to Initial 4-Week High-Dose Loading

    Directory of Open Access Journals (Sweden)

    Hector Garcia-Alcala

    2015-01-01

    Full Text Available Effective treatment of diabetic sensorimotor polyneuropathy remains a challenge. To assess the efficacy and safety of α-lipoic acid (ALA over 20 weeks, we conducted a multicenter randomized withdrawal open-label study, in which 45 patients with type 2 diabetes and symptomatic polyneuropathy were initially treated with ALA (600 mg tid for 4 weeks (phase 1. Subsequently, responders were randomized to receive ALA (600 mg qd; n=16 or to ALA withdrawal (n=17 for 16 weeks (phase 2. During phase 1, the Total Symptom Score (TSS decreased from 8.9 ± 1.8 points to 3.46 ± 2.0 points. During phase 2, TSS improved from 3.7 ± 1.9 points to 2.5 ± 2.5 points in the ALA treated group (p<0.05 and remained unchanged in the ALA withdrawal group. The use of analgesic rescue medication was higher in the ALA withdrawal group than ALA treated group (p<0.05. In conclusion, in type 2 diabetic patients with symptomatic polyneuropathy who responded to initial 4-week high-dose (600 mg tid administration of ALA, subsequent treatment with ALA (600 mg qd over 16 weeks improved neuropathic symptoms, whereas ALA withdrawal was associated with a higher use of rescue analgesic drugs. This trial is registered with ClinicalTrials.gov Identifier: NCT02439879.

  7. MRI evaluation of amyloid myopathy

    International Nuclear Information System (INIS)

    Metzler, J.P.; Fleckenstein, J.L.; Veterans Affairs Medical Center, Dallas, TX; White, C.L. III; Veterans Affairs Medical Center, Dallas, TX; Haller, R.G.; Greenlee, R.G. Jr.; Veterans Affairs Medical Center, Dallas, TX; Frenkel, E.P.; Veterans Affairs Medical Center, Dallas, TX

    1992-01-01

    Amyloid myopathy is a rare complication of primary amyloidosis. The magnetic resonance imaging (MRI) features of two patients with amyloid myopathy were studied. Slight prolongation of muscle T1 and T2 relaxation times was evident but the striking abnormality was marked reticulation of the subcutaneous fat. The clinical findings of indurated extremities far exceeds the minimal signal intenisty alteration seen in the muscles. The MR appearance of amyloid myopathy differs from that of other neuromuscular conditions in the minimal changes found in muscle, but the striking abnormality seen in subcutaneous fat makes it distinct from many neuromuscular conditions. (orig.)

  8. Endocytosed 2-Microglobulin Amyloid Fibrils Induce Necrosis and Apoptosis of Rabbit Synovial Fibroblasts by Disrupting Endosomal/Lysosomal Membranes: A Novel Mechanism on the Cytotoxicity of Amyloid Fibrils.

    Directory of Open Access Journals (Sweden)

    Tadakazu Okoshi

    Full Text Available Dialysis-related amyloidosis is a major complication in long-term hemodialysis patients. In dialysis-related amyloidosis, β2-microglobulin (β2-m amyloid fibrils deposit in the osteoarticular tissue, leading to carpal tunnel syndrome and destructive arthropathy with cystic bone lesions, but the mechanism by which these amyloid fibrils destruct bone and joint tissue is not fully understood. In this study, we assessed the cytotoxic effect of β2-m amyloid fibrils on the cultured rabbit synovial fibroblasts. Under light microscopy, the cells treated with amyloid fibrils exhibited both necrotic and apoptotic changes, while the cells treated with β2-m monomers and vehicle buffer exhibited no morphological changes. As compared to β2-m monomers and vehicle buffer, β2-m amyloid fibrils significantly reduced cellular viability as measured by the lactate dehydrogenase release assay and the 3-(4,5-di-methylthiazol-2-yl-2,5-diphenyltetrazolium bromide reduction assay and significantly increased the percentage of apoptotic cells as measured by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method. β2-m amyloid fibrils added to the medium adhered to cell surfaces, but did not disrupt artificial plasma membranes as measured by the liposome dye release assay. Interestingly, when the cells were incubated with amyloid fibrils for several hours, many endosomes/lysosomes filled with amyloid fibrils were observed under confocal laser microscopy and electron microscopy, Moreover, some endosomal/lysosomal membranes were disrupted by intravesicular fibrils, leading to the leakage of the fibrils into the cytosol and adjacent to mitochondria. Inhibition of actin-dependent endocytosis by cytochalasin D attenuated the toxicity of amyloid fibrils. These results suggest that endocytosed β2-m amyloid fibrils induce necrosis and apoptosis by disrupting endosomal/lysosomal membranes, and this novel mechanism on the cytotoxicity of amyloid

  9. Chronic inflammatory demyelinating polyneuropathy in adults: diagnostic approaches and first line therapy

    Directory of Open Access Journals (Sweden)

    N. А. Suponevа

    2016-01-01

    Full Text Available Chronic inflammatory demyelinating polyneuropathy (CIDP is among the key reasons of chronic polyneuropathies in adults. Diagnostic algorithm of CIDP in adults is presented. Diagnosis of CIDP is based on clinical and electrodiagnostic criteria of European Federation of Neurological Societies/Peripheral Nervous System in 2010. Principles of CIDP treatment are discussed, including modern trends of standard and 10 % IVIG solutions. 

  10. Demyelinating polyneuropathy, dermatomyositis, and interstitial pneumonitis associated with autoantibody against melanoma differentiation-associated gene 5

    Directory of Open Access Journals (Sweden)

    Yu-Hsiang Chiu

    2017-01-01

    Full Text Available Patients with serum anti-melanoma differentiation-associated gene 5 autoantibodies (anti-MDA5 are related to amyopathic dermatomyositis, especially in Asians. Here, we present a 46-year-old woman who was diagnosed with anti-MDA5-mediated demyelinating polyneuropathy clinically mimicking dermatomyositis. She had rapid progression of interstitial pneumonitis complicated with Pneumocystis jirovecii and Aspergillus pneumonia with septic shock. It is rare that patients with anti-MDA5-positive dermatomyositis present as demyelinating polyneuropathy.

  11. Subcutaneous immunoglobulin preserves muscle strength in chronic inflammatory demyelinating polyneuropathy

    DEFF Research Database (Denmark)

    Markvardsen, Lars Høj; Harbo, Thomas; Sindrup, Søren Hein

    2014-01-01

    evaluated after 3, 6 and 12 months. Primary end-points were changes in muscle strength evaluated by isokinetic dynamometry in four affected muscle groups and a composite score of muscle performance and function tests, including Medical Research Council (MRC) score, grip strength, 40-m walking test (40-MWT......BACKGROUND AND PURPOSE: Subcutaneous immunoglobulin (SCIG) is superior to placebo treatment for maintenance of muscle strength during 12 weeks in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). The present study evaluated whether SCIG preserves muscle strength for 1 year......) and nine-hole peg test (9-HPT). Secondary end-points were changes of each of the listed parameters at each time point as well as an overall disability sum score (ODSS). RESULTS: The dose of SCIG was significantly unaltered during the follow-up period. Overall the isokinetic dynamometry value increased by 7...

  12. Amyloid PET in pseudotumoral multiple sclerosis.

    Science.gov (United States)

    Matías-Guiu, Jordi A; Cabrera-Martín, María Nieves; Cortés-Martínez, Ana; Pytel, Vanesa; Moreno-Ramos, Teresa; Oreja-Guevara, Celia; Carreras, José Luis; Matías-Guiu, Jorge

    2017-07-01

    Pseudotumoral multiple sclerosis is a rare form of demyelinating disease of the central nervous system. Positron emission tomography (PET) using amyloid-tracers has also been suggested as a marker of damage in white matter lesions in multiple sclerosis due to the nonspecific uptake of these tracers in white matter. We present the case of a 59 year-old woman with a pathological-confirmed pseudotumoral multiple sclerosis, who was studied with the amyloid tracer 18 F-florbetaben. The patient had developed word-finding difficulties and right hemianopia twelve years ago. In that time, MRI showed a lesion on the left hemisphere with an infiltrating aspect in frontotemporal lobes. Brain biopsy showed demyelinating areas and inflammation. During the following years, two new clinical relapses occurred. 18 F-florbetaben PET showed lower uptake in the white matter lesion visualized in the CT and MRI images. Decreased tracer uptake was also observed in a larger area of the left hemisphere beyond the lesions observed on MRI or CT. White matter lesion volume on FLAIR was 44.2mL, and tracer uptake change between damaged white matter and normal appearing white matter was - 40.5%. Standardized uptake value was inferior in the pseudotumoral lesion than in the other white matter lesions. We report the findings of amyloid PET in a patient with pseudotumoral multiple sclerosis. This case provides further evidence on the role of amyloid PET in the assessment of white matter and demyelinating diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. No association of cortical amyloid load and EEG connectivity in older people with subjective memory complaints

    Directory of Open Access Journals (Sweden)

    Stefan Teipel

    2018-01-01

    Full Text Available Changes in functional connectivity of cortical networks have been observed in resting-state EEG studies in healthy aging as well as preclinical and clinical stages of AD. Little information, however, exists on associations between EEG connectivity and cortical amyloid load in people with subjective memory complaints. Here, we determined the association of global cortical amyloid load, as measured by florbetapir-PET, with functional connectivity based on the phase-lag index of resting state EEG data for alpha and beta frequency bands in 318 cognitively normal individuals aged 70–85 years with subjective memory complaints from the INSIGHT-preAD cohort. Within the entire group we did not find any significant associations between global amyloid load and phase-lag index in any frequency band. Assessing exclusively the subgroup of amyloid-positive participants, we found enhancement of functional connectivity with higher global amyloid load in the alpha and a reduction in the beta frequency bands. In the amyloid-negative participants, higher amyloid load was associated with lower connectivity in the low alpha band. However, these correlations failed to reach significance after controlling for multiple comparisons. The absence of a strong amyloid effect on functional connectivity may represent a selection effect, where individuals remain in the cognitively normal group only if amyloid accumulation does not impair cortical functional connectivity.

  14. Protein Polymers and Amyloids

    DEFF Research Database (Denmark)

    Risør, Michael Wulff

    2014-01-01

    Several human disorders are caused by a common general disease mechanism arising from abnormal folding and aggregation of the underlying protein. These include the prevalent dementias like Alzheimer’s and Parkinson’s, where accumulation of protein fibrillar structures, known as amyloid fibrils...... that inhibits its target protease through a large conformational change but mutations compromise this function and cause premature structural collapse into hyperstable polymers. Understanding the conformational disorders at a molecular level is not only important for our general knowledge on protein folding......, underlining the importance of understanding this relationship. The monomeric C-36 peptide was investigated by liquid-state NMR spectroscopy and found to be intrinsically disordered with minor propensities towards β-sheet structure. The plasticity of such a peptide makes it suitable for a whole range...

  15. Transplantation of dental pulp stem cells improves long-term diabetic polyneuropathy together with improvement of nerve morphometrical evaluation

    OpenAIRE

    Omi, Maiko; Hata, Masaki; Nakamura, Nobuhisa; Miyabe, Megumi; Ozawa, Shogo; Nukada, Hitoshi; Tsukamoto, Masami; Sango, Kazunori; Himeno, Tatsuhito; Kamiya, Hideki; Nakamura, Jiro; Takebe, Jun; Matsubara, Tatsuaki; Naruse, Keiko

    2017-01-01

    Background Although previous reports have revealed the therapeutic potential of stem cell transplantation in diabetic polyneuropathy, the effects of cell transplantation on long-term diabetic polyneuropathy have not been investigated. In this study, we investigated whether the transplantation of dental pulp stem cells (DPSCs) ameliorated long-term diabetic polyneuropathy in streptozotocin (STZ)-induced diabetic rats. Methods Forty-eight weeks after STZ injection, we transplanted DPSCs into th...

  16. Distal polyneuropathy in an adult Birman cat with toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Lorenzo Mari

    2016-02-01

    Full Text Available Case summary A 6-year-old female spayed Birman cat presented with a history of weight loss, stiff and short-strided gait in the pelvic limbs and reluctance to jump, progressing to non-ambulatory tetraparesis over 6 weeks. Poor body condition, dehydration and generalised muscle wastage were evident on general examination. Neurological examination revealed mildly depressed mental status, non-ambulatory flaccid tetraparesis and severely decreased proprioception and spinal reflexes in all four limbs. The neuroanatomical localisation was to the peripheral nervous system. Haematology, feline immunodeficiency virus/feline leukaemia virus serology, serum biochemistry, including creatine kinase and thyroxine, thoracic radiographs and abdominal ultrasound did not reveal significant abnormalities. Electromyography revealed fibrillation potentials and positive sharp waves in axial and appendicular muscles. Decreased motor conduction velocities and compound muscle action potential amplitudes were detected in ulnar and sciatic–tibial nerves. Residual latency was increased in the sciatic–tibial nerve. Histologically, several intramuscular nerve branches were depleted of myelinated fibres and a few showed mononuclear infiltrations. Toxoplasma gondii serology titres were compatible with active toxoplasmosis. Four days after treatment initiation with oral clindamycin the cat recovered the ability to walk. T gondii serology titres and neurological examination were normal after 11 and 16 weeks, respectively. Clindamycin was discontinued after 16 weeks. One year after presentation the cat showed mild relapse of clinical signs and seroconversion, which again resolved following treatment with clindamycin. Relevance and novel information To our knowledge, this is the first report of distal polyneuropathy associated with toxoplasmosis in a cat. This case suggests the inclusion of toxoplasmosis as a possible differential diagnosis for acquired polyneuropathies in

  17. Silymarin effect on amyloid-β plaque accumulation and gene expression of APP in an Alzheimer’s disease rat model

    OpenAIRE

    Yaghmaei, Parichehreh; Azarfar, Katia; Dezfulian, Mehrooz; Ebrahim-Habibi, Azadeh

    2014-01-01

    Background The deposition of amyloid peptides is associated with Alzheimer’s disease (AD). These amyloid peptides are derived from the amyloid protein precursor (APP). Silymarin, a standardized extract of milk thistle, which is currently used in liver diseases, may be effective in the inhibition of amyloid formation. However, its effect has not been assessed on APP expression. Results In this study, first, the effect of silymarin was examined on the passive avoidance learning in a rat model o...

  18. Clinical and imaging correlates of amyloid deposition in dementia with Lewy bodies.

    Science.gov (United States)

    Donaghy, Paul C; Firbank, Michael J; Thomas, Alan J; Lloyd, Jim; Petrides, George; Barnett, Nicola; Olsen, Kirsty; O'Brien, John T

    2018-04-19

    Amyloid deposition is common in dementia with Lewy bodies, but its pathophysiological significance is unclear. The objective of this study was to investigate the relationship between amyloid deposition and clinical profile, gray matter volume, and brain perfusion in dementia with Lewy bodies. Dementia with Lewy bodies (n = 37), Alzheimer's disease (n = 20), and controls (n = 20) underwent a thorough clinical assessment, 3T MRI, and early- and late-phase 18 F-Florbetapir PET-CT to assess cortical perfusion and amyloid deposition, respectively. Amyloid scans were visually categorized as positive or negative. Image analysis was carried out using statistical parametric mapping (SPM) 8. There were no significant differences between amyloid-positive and amyloid-negative dementia with Lewy bodies cases in age (P = .78), overall cognitive impairment (P = .83), level of functional impairment (P = .80), or any other clinical or cognitive scale. There were also no significant differences in hippocampal or gray matter volumes. However, amyloid-positive dementia with Lewy bodies cases had lower medial temporal lobe perfusion (P = .03) than amyloid-negative cases, although a combination of medial temporal lobe perfusion, hippocampal volume, and cognitive measures was unable to accurately predict amyloid status in dementia with Lewy bodies. Amyloid deposition was not associated with differences in clinical or neuropsychological profiles in dementia with Lewy bodies, but was associated with imaging evidence of medial temporal lobe dysfunction. The presence of amyloid in dementia with Lewy bodies cannot be identified on the basis of clinical and other imaging features and will require direct assessment via PET imaging or CSF. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf

  19. Cerebrospinal Fluid Amyloid β40 Is Decreased in Cerebral Amyloid Angiopathy

    Science.gov (United States)

    Verbeek, Marcel M.; Kremer, Berry P. H.; Rikkert, Marcel Olde; van Domburg, Peter H. M. F.; Skehan, Maureen E.; Greenberg, Steven M.

    2013-01-01

    Cerebral amyloid angiopathy is caused by deposition of the amyloid β protein in the cerebral vasculature. In analogy to previous observations in Alzheimer disease, we hypothesized that analysis of amyloid β40 and β42 proteins in the cerebrospinal fluid might serve as a molecular biomarker. We observed strongly decreased cerebrospinal fluid amyloid β40 (p < 0.01 vs controls or Alzheimer disease) and amyloid β42 concentrations (p < 0.001 vs controls and p < 0.05 vs Alzheimer disease) in cerebral amyloid angiopathy patients. The combination of amyloid β42 and total tau discriminated cerebral amyloid angiopathy from controls, with an area under the receiver operator curve of 0.98. Our data are consistent with neuropathological evidence that amyloid β40 as well as amyloid β42 protein are selectively trapped in the cerebral vasculature from interstitial fluid drainage pathways that otherwise transport amyloid β proteins toward the cerebrospinal fluid. PMID:19743453

  20. Towards a Pharmacophore for Amyloid

    Energy Technology Data Exchange (ETDEWEB)

    Landau, Meytal; Sawaya, Michael R.; Faull, Kym F.; Laganowsky, Arthur; Jiang, Lin; Sievers, Stuart A.; Liu, Jie; Barrio, Jorge R.; Eisenberg, David (UCLA)

    2011-09-16

    Diagnosing and treating Alzheimer's and other diseases associated with amyloid fibers remains a great challenge despite intensive research. To aid in this effort, we present atomic structures of fiber-forming segments of proteins involved in Alzheimer's disease in complex with small molecule binders, determined by X-ray microcrystallography. The fiber-like complexes consist of pairs of {beta}-sheets, with small molecules binding between the sheets, roughly parallel to the fiber axis. The structures suggest that apolar molecules drift along the fiber, consistent with the observation of nonspecific binding to a variety of amyloid proteins. In contrast, negatively charged orange-G binds specifically to lysine side chains of adjacent sheets. These structures provide molecular frameworks for the design of diagnostics and drugs for protein aggregation diseases. The devastating and incurable dementia known as Alzheimer's disease affects the thinking, memory, and behavior of dozens of millions of people worldwide. Although amyloid fibers and oligomers of two proteins, tau and amyloid-{beta}, have been identified in association with this disease, the development of diagnostics and therapeutics has proceeded to date in a near vacuum of information about their structures. Here we report the first atomic structures of small molecules bound to amyloid. These are of the dye orange-G, the natural compound curcumin, and the Alzheimer's diagnostic compound DDNP bound to amyloid-like segments of tau and amyloid-{beta}. The structures reveal the molecular framework of small-molecule binding, within cylindrical cavities running along the {beta}-spines of the fibers. Negatively charged orange-G wedges into a specific binding site between two sheets of the fiber, combining apolar binding with electrostatic interactions, whereas uncharged compounds slide along the cavity. We observed that different amyloid polymorphs bind different small molecules, revealing that a

  1. Amyloid PET in European and North American cohorts; and exploring age as a limit to clinical use of amyloid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chiotis, Konstantinos [Karolinska Institutet, Department of NVS, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Stockholm (Sweden); Carter, Stephen F. [Karolinska Institutet, Department of NVS, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Stockholm (Sweden); University of Manchester, Wolfson Molecular Imaging Centre, Institute of Brain, Behaviour and Mental Health, Manchester (United Kingdom); Farid, Karim [Karolinska Institutet, Department of NVS, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Stockholm (Sweden); APHP, Hotel-Dieu Hospital, Department of Nuclear Medicine, Paris (France); Savitcheva, Irina [Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden); Nordberg, Agneta [Karolinska Institutet, Department of NVS, Center for Alzheimer Research, Translational Alzheimer Neurobiology, Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Geriatric Medicine, Stockholm (Sweden); Collaboration: for the Diagnostic Molecular Imaging (DiMI) network and the Alzheimer' s Disease Neuroimaging Initiative

    2015-09-15

    Several radiotracers that bind to fibrillar amyloid-beta in the brain have been developed and used in various patient cohorts. This study aimed to investigate the comparability of two amyloid positron emission tomography (PET) tracers as well as examine how age affects the discriminative properties of amyloid PET imaging. Fifty-one healthy controls (HCs), 72 patients with mild cognitive impairment (MCI) and 90 patients with Alzheimer's disease (AD) from a European cohort were scanned with [11C]Pittsburgh compound-B (PIB) and compared with an age-, sex- and disease severity-matched population of 51 HC, 72 MCI and 84 AD patients from a North American cohort who were scanned with [18F]Florbetapir. An additional North American population of 246 HC, 342 MCI and 138 AD patients with a Florbetapir scan was split by age (55-75 vs 76-93 y) into groups matched for gender and disease severity. PET template-based analyses were used to quantify regional tracer uptake. The mean regional uptake patterns were similar and strong correlations were found between the two tracers across the regions of interest in HC (ρ = 0.671, p = 0.02), amyloid-positive MCI (ρ = 0.902, p < 0.001) and AD patients (ρ = 0.853, p < 0.001). The application of the Florbetapir cut-off point resulted in a higher proportion of amyloid-positive HC and a lower proportion of amyloid-positive AD patients in the older group (28 and 30 %, respectively) than in the younger group (19 and 20 %, respectively). These results illustrate the comparability of Florbetapir and PIB in unrelated but matched patient populations. The role of amyloid PET imaging becomes increasingly important with increasing age in the diagnostic assessment of clinically impaired patients. (orig.)

  2. Amyloid PET in European and North American cohorts; and exploring age as a limit to clinical use of amyloid imaging

    International Nuclear Information System (INIS)

    Chiotis, Konstantinos; Carter, Stephen F.; Farid, Karim; Savitcheva, Irina; Nordberg, Agneta

    2015-01-01

    Several radiotracers that bind to fibrillar amyloid-beta in the brain have been developed and used in various patient cohorts. This study aimed to investigate the comparability of two amyloid positron emission tomography (PET) tracers as well as examine how age affects the discriminative properties of amyloid PET imaging. Fifty-one healthy controls (HCs), 72 patients with mild cognitive impairment (MCI) and 90 patients with Alzheimer's disease (AD) from a European cohort were scanned with [11C]Pittsburgh compound-B (PIB) and compared with an age-, sex- and disease severity-matched population of 51 HC, 72 MCI and 84 AD patients from a North American cohort who were scanned with [18F]Florbetapir. An additional North American population of 246 HC, 342 MCI and 138 AD patients with a Florbetapir scan was split by age (55-75 vs 76-93 y) into groups matched for gender and disease severity. PET template-based analyses were used to quantify regional tracer uptake. The mean regional uptake patterns were similar and strong correlations were found between the two tracers across the regions of interest in HC (ρ = 0.671, p = 0.02), amyloid-positive MCI (ρ = 0.902, p < 0.001) and AD patients (ρ = 0.853, p < 0.001). The application of the Florbetapir cut-off point resulted in a higher proportion of amyloid-positive HC and a lower proportion of amyloid-positive AD patients in the older group (28 and 30 %, respectively) than in the younger group (19 and 20 %, respectively). These results illustrate the comparability of Florbetapir and PIB in unrelated but matched patient populations. The role of amyloid PET imaging becomes increasingly important with increasing age in the diagnostic assessment of clinically impaired patients. (orig.)

  3. Proteomic screening for amyloid proteins.

    Directory of Open Access Journals (Sweden)

    Anton A Nizhnikov

    Full Text Available Despite extensive study, progress in elucidation of biological functions of amyloids and their role in pathology is largely restrained due to the lack of universal and reliable biochemical methods for their discovery. All biochemical methods developed so far allowed only identification of glutamine/asparagine-rich amyloid-forming proteins or proteins comprising amyloids that form large deposits. In this article we present a proteomic approach which may enable identification of a broad range of amyloid-forming proteins independently of specific features of their sequences or levels of expression. This approach is based on the isolation of protein fractions enriched with amyloid aggregates via sedimentation by ultracentrifugation in the presence of strong ionic detergents, such as sarkosyl or SDS. Sedimented proteins are then separated either by 2D difference gel electrophoresis or by SDS-PAGE, if they are insoluble in the buffer used for 2D difference gel electrophoresis, after which they are identified by mass-spectrometry. We validated this approach by detection of known yeast prions and mammalian proteins with established capacity for amyloid formation and also revealed yeast proteins forming detergent-insoluble aggregates in the presence of human huntingtin with expanded polyglutamine domain. Notably, with one exception, all these proteins contained glutamine/asparagine-rich stretches suggesting that their aggregates arose due to polymerization cross-seeding by human huntingtin. Importantly, though the approach was developed in a yeast model, it can easily be applied to any organism thus representing an efficient and universal tool for screening for amyloid proteins.

  4. 11C-PiB PET assessment of change in fibrillar amyloid-beta load in patients with Alzheimer's disease treated with bapineuzumab: a phase 2, double-blind, placebo-controlled, ascending-dose study.

    Science.gov (United States)

    Rinne, Juha O; Brooks, David J; Rossor, Martin N; Fox, Nick C; Bullock, Roger; Klunk, William E; Mathis, Chester A; Blennow, Kaj; Barakos, Jerome; Okello, Aren A; Rodriguez Martinez de Liano, Sofia; Liu, Enchi; Koller, Martin; Gregg, Keith M; Schenk, Dale; Black, Ronald; Grundman, Michael

    2010-04-01

    the overall mean difference. Adverse events were typically mild to moderate in severity and transient. Two patients in the 2.0 mg/kg bapineuzumab group had transient cerebral vasogenic oedema. Treatment with bapineuzumab for 78 weeks reduced cortical (11)C-PiB retention compared with both baseline and placebo. (11)C-PiB PET seems to be useful in assessing the effects of potential Alzheimer's disease treatments on cortical fibrillar amyloid-beta load in vivo. Elan Pharmaceuticals and Wyeth Research. 2010 Elsevier Ltd. All rights reserved.

  5. The evaluation of distal symmetric polyneuropathy: a physician survey of clinical practice.

    Science.gov (United States)

    Callaghan, Brian C; Kerber, Kevin; Smith, Andrea L; Fendrick, A Mark; Feldman, Eva L

    2012-03-01

    To define current clinical practice for evaluating distal symmetric polyneuropathy. Using a modified Dillman method, we sent surveys to 600 internists, 600 neurologists, and 45 neuromuscular specialists selected from the American Medical Association Physician Masterfile. Survey questions pertained to which tests providers would order in the following 3 scenarios: (1) the initial evaluation of distal symmetric polyneuropathy, (2) the use of additional tests if the initial evaluation was unrevealing, and (3) patients with diabetes. The t test was used to compare the number of tests ordered by physician type, and the χ(2) test was used to compare proportions of tests ordered. National survey of physicians. Internists, neurologists, and neuromuscular specialists. The response rate was 35%. Overall, many tests were ordered for the full evaluation of distal symmetric polyneuropathy (mean [SD], 16.5 [7.2] tests), and there was substantial variation within and between provider types. Internists ordered fewer tests (mean [SD], 14.5 [6.1] tests) than did neurologists (mean [SD], 17.5 [7.9] tests) (P current practice intent on evaluating distal symmetric polyneuropathy is highly variable and differs widely. For this disorder of the peripheral nerves, a high-yield test such as the glucose tolerance test is rarely used, whereas magnetic resonance imaging is likely overused. Research that defines the optimal evaluation of distal symmetric polyneuropathy has the potential to result in more efficient care.

  6. Identification of Plant Extracts that Inhibit the Formation of Diabetes-Linked IAPP Amyloid.

    Science.gov (United States)

    Fuentes, Ana Lucia; Hennessy, Kathleen; Pascual, Jacob; Pepe, Nicole; Wang, In; Santiago, Alexander; Chaggan, Cynthia; Martinez, Jessica; Rivera, Evelyn; Cota, Paola; Cunha, Christina; Nogaj, Luiza A; Moffet, David A

    2016-03-01

    The extracts of 27 vegetables, spices and herbs were screened for their functional ability to inhibit the aggregation of islet amyloid polypeptide (IAPP, amylin) into toxic amyloid aggregates. The aggregation of IAPP has been directly linked to the death of pancreatic β-islet cells in type 2 diabetes. Inhibiting the aggregation of IAPP is believed to have the potential to slow, if not prevent entirely, the progression of this disease. As vegetables, spices and herbs are known to possess many different positive health effects, the extracts of 27 plants (abundant within the United States and spanning several plant families) were screened for their ability to inhibit the formation of toxic IAPP aggregates. Their anti-amyloid activities were assessed through (1) thioflavin T binding assays, (2) visualization of amyloid fibers using atomic force microscopy and (3) cell rescue studies. From this research, mint, peppermint, red bell pepper and thyme emerged as possessing the greatest anti-amyloid activity.

  7. Association of Cerebral Amyloid-β Aggregation With Cognitive Functioning in Persons Without Dementia

    DEFF Research Database (Denmark)

    Jansen, Willemijn J; Ossenkoppele, Rik; Tijms, Betty M

    2018-01-01

    Importance: Cerebral amyloid-β aggregation is an early event in Alzheimer disease (AD). Understanding the association between amyloid aggregation and cognitive manifestation in persons without dementia is important for a better understanding of the course of AD and for the design of prevention...... trials. Objective: To investigate whether amyloid-β aggregation is associated with cognitive functioning in persons without dementia. Design, Setting, and Participants: This cross-sectional study included 2908 participants with normal cognition and 4133 with mild cognitive impairment (MCI) from 53.......28) and to assess whether this association was moderated by age, sex, educational level, or apolipoprotein E genotype. Results: Among 2908 persons with normal cognition (mean [SD] age, 67.4 [12.8] years), amyloid positivity was associated with low memory scores after age 70 years (mean difference in amyloid...

  8. Health-related quality of life and its predictive role for analgesic effect in patients with painful polyneuropathy

    DEFF Research Database (Denmark)

    Otto, Marit; Bach, Flemming W; Jensen, Troels S

    2007-01-01

    Painful polyneuropathy is a common neuropathic pain condition. The present study describes health-related quality of life (HRQL) in a sample of patients with painful polyneuropathy of different origin and the possible predictive role of HRQL for analgesic effect. Ninety-three patients with a diag...

  9. The anticonvulsant levetiracetam for the treatment of pain in polyneuropathy: A randomized, placebo-controlled, cross-over trial

    DEFF Research Database (Denmark)

    Holbech, Jakob V; Otto, Marit; Bach, Flemming Winther

    2011-01-01

    of this study was to test the analgesic effect of levetiracetam in painful polyneuropathy. METHODS: This was a randomized, double-blind, placebo-controlled, cross-over trial with levetiracetam 3000mg/day versus placebo (6-week treatment periods). Patients with diagnosed polyneuropathy and symptoms for more than...

  10. Re-emergence of hereditary polyneuropathy in scandinavian alaskan malamute dogs-old enemy or new entity? A case series

    DEFF Research Database (Denmark)

    Jäderlund, Karin Hultin; Rohdin, Cecilia; Berendt, Mette

    2017-01-01

    A homozygous mutation has been identified in the N-myc downstream-regulated gene 1 (NDRG1) in recent cases of polyneuropathy in Alaskan malamute dogs from the Nordic countries and USA. The objective of the present study was to determine if cases diagnosed 30-40 years ago with polyneuropathy...

  11. Diabetic Polyneuropathy in Type 2 Diabetes Mellitus: Inflammation, Oxidative Stress, and Mitochondrial Function

    Directory of Open Access Journals (Sweden)

    Luis Miguel Román-Pintos

    2016-01-01

    Full Text Available Diabetic polyneuropathy (DPN is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients. Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids.

  12. Association between Diabetic Polyneuropathy and Cardiovascular Complications in Type 2 Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Jin Ook Chung

    2011-08-01

    Full Text Available BackgroundDiabetes mellitus is a major independent risk factor for cardiovascular disease (CVD, but high cardiovascular risk in diabetes mellitus patients is not completely explained by clustering traditional risk factors. Recently, associations between diabetic polyneuropathy (DPN and macrovasculopathy have been suggested. We aimed to assess associations between DPN and cardiovascular complications in type 2 diabetic patients.MethodsMicrovascular and cardiovascular complications were evaluated in 1,041 type 2 diabetic patients.ResultsIn patients with DPN, the age, prevalence of hypertension, diabetes duration, systolic blood pressure, pulse pressure, and hemoglobin glycation (HbA1c levels were significantly higher, while the high density lipoprotein cholesterol (HDL-C levels were lower than in those without DPN. The prevalence of CVD was higher in patients with DPN. In multivariate analysis, DPN was independently associated with CVD (odds ratio, 1.801; 95% confidence interval, 1.009 to 3.214.ConclusionOur results showed that DPN was associated with a high prevalence of cardiovascular disease in type 2 diabetic patients, but further studies are needed to investigate the causative nature of associations between DPN and CVD.

  13. Diabetic Polyneuropathy in Type 2 Diabetes Mellitus: Inflammation, Oxidative Stress, and Mitochondrial Function.

    Science.gov (United States)

    Román-Pintos, Luis Miguel; Villegas-Rivera, Geannyne; Rodríguez-Carrizalez, Adolfo Daniel; Miranda-Díaz, Alejandra Guillermina; Cardona-Muñoz, Ernesto Germán

    2016-01-01

    Diabetic polyneuropathy (DPN) is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients). Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids).

  14. Jamar hand-held grip dynamometry in chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Rajabally, Yusuf A; Narasimhan, Manisha

    2013-02-15

    Few studies have evaluated the functional and electrophysiological correlates of hand-held grip dynamometry in neuromuscular disease. The practical value of normative values remains uncertain in clinical practice. We aimed to ascertain the value, clinical and electrophysiological correlates, as well as utility of normative values for grip dynamometry, in a cohort of subjects with chronic inflammatory demyelinating polyneuropathy (CIDP). We performed a cross-sectional study of 31 prospectively recruited subjects with CIDP, using Jamar hand-held grip dynamometry, conventional clinical assessments and electrophysiology. Grip dynamometry correlated highly with motor, sensory and functional scores in the upper limbs as well as with global function. There were significant correlations with summated median/ulnar, and ulnar compound muscle action potentials. Patients' readings were significantly lower than median normative values but comparable to fifth percentile normative figures. Jamar grip dynamometry is a reliable measure of global neurological status in patients with CIDP, not limited to upper limb or exclusively motor function. At optimum level of function, CIDP patients had comparable dynamometry recordings to fifth percentile normative values, which may represent a realistic aim for treated subjects with the disorder, with currently available therapies. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  15. Clinical and diagnostic characteristics of patients with suspected polyneuropathy

    Directory of Open Access Journals (Sweden)

    Mikhailova Е.V.

    2013-09-01

    Full Text Available Objective: to study the causes and clinical manifestations of disease in children referred for hospitalization in children infectious diseases hospital in Saratov with a diagnosis of «acute flaccid paralysis». Material and methods: 157 children with the diagnosis on admission of the guide «acute flaccid paralysis». Conducted clinical examination and laboratory tests included a general analysis of cerebrospinal fluid, urine, virological examination of nasal swabs and faeces, with the definition of a serological ELISA method and RPHA immunoglobulins to influenza, rubella, and enterovirus, immunological study of blood, cerebrospinal fluid PCR, electromyography of the affected limbs. Results. 77 patients (49% with the disease associated with the violation of the musculoskeletal system were registered. In the other cases revealed polyneuropathy was not of poliovirus etiology. Etiological nature of the disease could be explained by 54% of patients. In 37 (46% patients the diagnosis was formulated in accordance with the severity of paralysis. One child was diagnosed with a vaccine-associated poliomyelitis. Conclusion. The diagnosis of «acute flaccid paralysis» used as administered requires a detailed interpretation in a hospital.

  16. In situ hybridization of nucleus basalis neurons shows increased β-amyloid mRNA in Alzheimer disease

    International Nuclear Information System (INIS)

    Cohen, M.L.; Golde, T.E.; Usiak, M.F.; Younkin, L.H.; Younkin, S.G.

    1988-01-01

    To determine which cells within the brain produce β-amyloid mRNA and to assess expression of the β-amyloid gene in Alzheimer disease, the authors analyzed brain tissue from Alzheimer and control patients by in situ hybridization. The results demonstrate that β-amyloid mRNA is produced by neurons in the nucleus basalis of Meynert and cerebral cortex and that nuclues basalis perikarya from Alzheimer patients consistently hybridize more β-amyloid probe than those from controls. These observations support the hypothesis that increased expression of the β-amyloid gene plays an important role in the deposition of amyloid in the brains of patients with Alzheimer disease

  17. Late-onset distal polyneuropathy due to acute organophosphate intoxication case report.

    Science.gov (United States)

    Genel, Ferah; Arslanoğlu, Sertaç; Uran, Nedret; Doğan, Mustafa; Atlihan, Füsun

    2003-01-01

    Intoxications due to organophosphate insecticides are common in our country, since agriculture has an important place. Besides the well known acute cholinergic toxicity, these compounds may cause late-onset distal polyneuropathy occurring two to three weeks after the acute exposure. An eight-year-old boy and a 13-year-old girl admitted to the hospital with gait disturbances. Beginning 15 and 20 days, respectively, after organophosphate ingestion. Neurologic examination revealed bilateral dropped foot, absent Achilles tendon reflexes and peripheral sensory loss. Electromyography demonstrated motor weighed sensory-motor polyneuropathy with axonal degeneration significant in the distal parts of bilateral lower extremities. Biochemical, radiological findings and magnetic resonance imagings were normal. The two cases were taken under a physiotherapy program. The two cases are presented here since organophosphate poisonings are common in our country, and since late-onset polyneuropathy is not a well known clinical presentation as acute toxicity.

  18. B-Amyloid Precursor Protein Staining of the Brain in Sudden Infant and Early Childhood Death

    DEFF Research Database (Denmark)

    Jensen, Lisbeth Lund; Banner, Jytte; Ulhøi, Benedicte Parm

    2013-01-01

    To develop and validate a scoring method for assessing β-amyloid precursor protein (APP) staining in cerebral white matter and to investigate the occurrence, amount and deposition pattern based on the cause of death in infants and young children....

  19. Altered β-Amyloid Precursor Protein Isoforms in Mexican Alzheimer’s Disease Patients

    Directory of Open Access Journals (Sweden)

    V. J. Sánchez-González

    2006-01-01

    Full Text Available Objective: To determine the β-amyloid precursor protein (βAPP isoforms ratio as a risk factor for Alzheimer’s Disease and to assess its relationship with demographic and genetic variables of the disease.

  20. Cognitive reserve and β-amyloid pathology in Parkinson disease.

    Science.gov (United States)

    Lucero, Carolyn; Campbell, Meghan C; Flores, Hubert; Maiti, Baijayanta; Perlmutter, Joel S; Foster, Erin R

    2015-08-01

    Dementia in Parkinson disease (PD) is associated with abnormal accumulation of proteins, including β-amyloid, in cortical regions. High cognitive reserve capacity may protect cognition from β-amyloid and delay the onset of dementia. We tested the cognitive reserve theory in PD by determining whether educational attainment, a proxy for cognitive reserve, modifies the correlation between cortical β-amyloid accumulation and cognitive impairment. PD participants (N = 155) underwent MRI to quantify brain volume and [(11)C] PiB PET imaging to quantify fibrillar β-amyloid deposition. Mean cortical binding potentials (MCBP) were calculated for each participant, with higher scores indicating more fibrillar β-amyloid. Global cognitive function was assessed using the Clinical Dementia Rating (CDR) and Mini-Mental State Examination (MMSE). Multiple linear regression analysis was used to determine whether education modified the relationship between MCBP and cognitive function after controlling for brain volume. MCBP interacted with educational attainment to predict scores on each of the cognitive outcome measures (ps ≤ 0.02). Post-hoc analysis revealed that the effect of MCBP on cognitive function changed once the level of education reached 16 years. For participants with less than 16 years of education (n = 68), higher MCBP correlated with worse cognitive function, with MCBP accounting for 8-30% of the variance in MMSE and CDR scores (ps ≤ 0.02). For participants with at least 16 years of education (n = 87), MCBP did not correlate with MMSE or CDR scores (R(2)s cognitive reserve theory in PD and suggest that education may protect PD patients' cognition against cortical β-amyloid pathology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Nanomechanical properties of single amyloid fibrils

    International Nuclear Information System (INIS)

    Sweers, K K M; Bennink, M L; Subramaniam, V

    2012-01-01

    Amyloid fibrils are traditionally associated with neurodegenerative diseases like Alzheimer’s disease, Parkinson’s disease or Creutzfeldt-Jakob disease. However, the ability to form amyloid fibrils appears to be a more generic property of proteins. While disease-related, or pathological, amyloid fibrils are relevant for understanding the pathology and course of the disease, functional amyloids are involved, for example, in the exceptionally strong adhesive properties of natural adhesives. Amyloid fibrils are thus becoming increasingly interesting as versatile nanobiomaterials for applications in biotechnology. In the last decade a number of studies have reported on the intriguing mechanical characteristics of amyloid fibrils. In most of these studies atomic force microscopy (AFM) and atomic force spectroscopy play a central role. AFM techniques make it possible to probe, at nanometer length scales, and with exquisite control over the applied forces, biological samples in different environmental conditions. In this review we describe the different AFM techniques used for probing mechanical properties of single amyloid fibrils on the nanoscale. An overview is given of the existing mechanical studies on amyloid. We discuss the difficulties encountered with respect to the small fibril sizes and polymorphic behavior of amyloid fibrils. In particular, the different conformational packing of monomers within the fibrils leads to a heterogeneity in mechanical properties. We conclude with a brief outlook on how our knowledge of these mechanical properties of the amyloid fibrils can be exploited in the construction of nanomaterials from amyloid fibrils. (topical review)

  2. Functional Amyloid Formation within Mammalian Tissue.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available Amyloid is a generally insoluble, fibrous cross-beta sheet protein aggregate. The process of amyloidogenesis is associated with a variety of neurodegenerative diseases including Alzheimer, Parkinson, and Huntington disease. We report the discovery of an unprecedented functional mammalian amyloid structure generated by the protein Pmel17. This discovery demonstrates that amyloid is a fundamental nonpathological protein fold utilized by organisms from bacteria to humans. We have found that Pmel17 amyloid templates and accelerates the covalent polymerization of reactive small molecules into melanin-a critically important biopolymer that protects against a broad range of cytotoxic insults including UV and oxidative damage. Pmel17 amyloid also appears to play a role in mitigating the toxicity associated with melanin formation by sequestering and minimizing diffusion of highly reactive, toxic melanin precursors out of the melanosome. Intracellular Pmel17 amyloidogenesis is carefully orchestrated by the secretory pathway, utilizing membrane sequestration and proteolytic steps to protect the cell from amyloid and amyloidogenic intermediates that can be toxic. While functional and pathological amyloid share similar structural features, critical differences in packaging and kinetics of assembly enable the usage of Pmel17 amyloid for normal function. The discovery of native Pmel17 amyloid in mammals provides key insight into the molecular basis of both melanin formation and amyloid pathology, and demonstrates that native amyloid (amyloidin may be an ancient, evolutionarily conserved protein quaternary structure underpinning diverse pathways contributing to normal cell and tissue physiology.

  3. Functional amyloid formation within mammalian tissue.

    Directory of Open Access Journals (Sweden)

    Douglas M Fowler

    2006-01-01

    Full Text Available Amyloid is a generally insoluble, fibrous cross-beta sheet protein aggregate. The process of amyloidogenesis is associated with a variety of neurodegenerative diseases including Alzheimer, Parkinson, and Huntington disease. We report the discovery of an unprecedented functional mammalian amyloid structure generated by the protein Pmel17. This discovery demonstrates that amyloid is a fundamental nonpathological protein fold utilized by organisms from bacteria to humans. We have found that Pmel17 amyloid templates and accelerates the covalent polymerization of reactive small molecules into melanin-a critically important biopolymer that protects against a broad range of cytotoxic insults including UV and oxidative damage. Pmel17 amyloid also appears to play a role in mitigating the toxicity associated with melanin formation by sequestering and minimizing diffusion of highly reactive, toxic melanin precursors out of the melanosome. Intracellular Pmel17 amyloidogenesis is carefully orchestrated by the secretory pathway, utilizing membrane sequestration and proteolytic steps to protect the cell from amyloid and amyloidogenic intermediates that can be toxic. While functional and pathological amyloid share similar structural features, critical differences in packaging and kinetics of assembly enable the usage of Pmel17 amyloid for normal function. The discovery of native Pmel17 amyloid in mammals provides key insight into the molecular basis of both melanin formation and amyloid pathology, and demonstrates that native amyloid (amyloidin may be an ancient, evolutionarily conserved protein quaternary structure underpinning diverse pathways contributing to normal cell and tissue physiology.

  4. Pyramidal tract deficits and polyneuropathy in hyperthyroidism, Combination clinically mimicking amyotrophic lateral sclerosis.

    Science.gov (United States)

    Fisher, M; Mateer, J E; Ullrich, I; Gutrecht, J A

    1985-06-01

    Generalized weakness, intermittent dysphagia, and a 40-pound weight loss developed in an elderly man over a six-month period. Examination revealed weakness, atrophy and fasciculations of extremity musculature, pseudobulbar speech, hyperactive upper extremity reflexes, and extensor toe signs without sensory loss. Results of electrodiagnostic studies were consistent with an axonal polyneuropathy. Endocrinologic results were compatible with hyperthyroidism. Radioiodine therapy resulted in resolution of clinical neurologic symptoms and signs within seven months. This case illustrates a previously undescribed concurrence of hyperthyroid associated polyneuropathy and pyramidal tract dysfunction that led to an initial clinical diagnosis of amyotrophic lateral sclerosis.

  5. Wernicke-korsakoff encephalopathy and polyneuropathy after gastroplasty for morbid obesity: report of a case.

    Science.gov (United States)

    Cirignotta, F; Manconi, M; Mondini, S; Buzzi, G; Ambrosetto, P

    2000-09-01

    Gastric partitioning is a surgical procedure for the treatment of morbid obesity that may engender neurological complications, such as Wernicke encephalopathy and polyneuropathy. A specialist hospital. A 36-year-old woman developed Wernicke-Korsakoff encephalopathy and polyneuropathy 3 months after gastroplasty for morbid obesity. A magnetic resonance scan documented the diagnosis, and a clear improvement occurred after parenteral thiamine treatment. In our patient and in previously described cases of the literature, postsurgical vomiting is a constant finding that seems to be the precipitating factor of neurological complications of gastric partitioning. Persistent vomiting after gastroplasty for morbid obesity should be considered an alarming symptom to treat immediately with appropriate measures.

  6. Sensory-motor axonal polyneuropathy involving cranial nerves: An uncommon manifestation of disulfiram toxicity.

    Science.gov (United States)

    Santos, Telma; Martins Campos, António; Morais, Hugo

    2017-01-01

    Disulfiram (tetraethylthiuram disulfide) has been used for the treatment of alcohol dependence. An axonal sensory-motor polyneuropathy with involvement of cranial pairs due to disulfiram is exceedingly rare. The authors report a unique case of an extremely severe axonal polyneuropathy involving cranial nerves that developed within weeks after a regular dosage of 500mg/day disulfiram. To the authors best knowledge, such a severe and rapidly-progressive course has never been described with disulfiram dosages of only 500mg/day. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Terapeutika amyloidóz

    Czech Academy of Sciences Publication Activity Database

    Holubová, Monika; Hrubý, Martin

    2016-01-01

    Roč. 110, č. 12 (2016), s. 851-859 ISSN 0009-2770 R&D Projects: GA MŠk(CZ) LO1507 Institutional support: RVO:61389013 Keywords : amyloidosis * amyloid * Alzheimer's disease Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.387, year: 2016 http://www.chemicke-listy.cz/common/article-vol_110-issue_12-page_851.html

  8. Histological regression of amyloid in AL amyloidosis is exclusively seen after normalization of serum free light chain

    NARCIS (Netherlands)

    van Gameren, Ingrid I.; van Rijswijk, Martin H.; Bijzet, Johan; Vellenga, Edo; Hazenberg, Bouke P.

    Background Histological regression of amyloid has not been studied systematically but is assessed by clinical parameters. We analyzed the change of amyloid deposition in fat tissue in patients with AL amyloidosis following chemotherapy and studied the relation with type of hematologic response.

  9. 18F-FPYBF-2, a new F-18 labelled amyloid imaging PET tracer: biodistribution and radiation dosimetry assessment of first-in-man 18F-FPYBF-2 PET imaging.

    Science.gov (United States)

    Nishii, Ryuichi; Higashi, Tatsuya; Kagawa, Shinya; Okuyama, Chio; Kishibe, Yoshihiko; Takahashi, Masaaki; Okina, Tomoko; Suzuki, Norio; Hasegawa, Hiroshi; Nagahama, Yasuhiro; Ishizu, Koichi; Oishi, Naoya; Kimura, Hiroyuki; Watanabe, Hiroyuki; Ono, Masahiro; Saji, Hideo; Yamauchi, Hiroshi

    2018-05-01

    Recently, a benzofuran derivative for the imaging of β-amyloid plaques, 5-(5-(2-(2-(2- 18 F-fluoroethoxy)ethoxy)ethoxy)benzofuran-2-yl)- N-methylpyridin-2-amine ( 18 F-FPYBF-2) has been validated as a tracer for amyloid imaging and it was found that 18 F-FPYBF-2 PET/CT is a useful and reliable diagnostic tool for the evaluation of AD (Higashi et al. Ann Nucl Med, https://doi.org/10.1007/s12149-018-1236-1 , 2018). The aim of this study was to assess the biodistribution and radiation dosimetry of diagnostic dosages of 18 F-FPYBF-2 in normal healthy volunteers as a first-in-man study. Four normal healthy volunteers (male: 3, female: 1; mean age: 40 ± 17; age range 25-56) were included and underwent 18 F-FPYBF-2 PET/CT study for the evaluation of radiation exposure and pharmacokinetics. A 10-min dynamic PET/CT scan of the body (chest and abdomen) was performed at 0-10 min and a 15-min whole-body static scan was performed six times after the injection of 18 F-FPYBF-2. After reconstructing PET and CT image data, individual organ time-activity curves were estimated by fitting volume of interest data from the dynamic scan and whole-body scans. The OLINDA/EXM version 2.0 software was used to determine the whole-body effective doses. Dynamic PET imaging demonstrated that the hepatobiliary and renal systems were the principal pathways of clearance of 18 F-FPYBF-2. High uptake in the liver and the gall bladder, the stomach, and the kidneys were demonstrated, followed by the intestines and the urinary bladder. The ED for the adult dosimetric model was estimated to be 8.48 ± 1.25 µSv/MBq. The higher absorbed doses were estimated for the liver (28.98 ± 12.49 and 36.21 ± 15.64 µGy/MBq), the brain (20.93 ± 4.56 and 23.05 ± 5.03µ Gy/MBq), the osteogenic cells (9.67 ± 1.67 and 10.29 ± 1.70 µGy/MBq), the small intestines (9.12 ± 2.61 and 11.12 ± 3.15 µGy/MBq), and the kidneys (7.81 ± 2.62 and 8.71 ± 2.90 µGy/MBq) for

  10. The impact of type 1 diabetes and diabetic polyneuropathy on muscle strength and fatigability.

    Science.gov (United States)

    Orlando, Giorgio; Balducci, Stefano; Bazzucchi, Ilenia; Pugliese, Giuseppe; Sacchetti, Massimo

    2017-06-01

    Although it is widely accepted that diabetic polyneuropathy (DPN) is linked to a marked decline in neuromuscular performance, information on the possible impact of type 1 diabetes (T1D) on muscle strength and fatigue remains unclear. The purpose of this study was to investigate the effects of T1D and DPN on strength and fatigability in knee extensor muscles. Thirty-one T1D patients (T1D), 22 T1D patients with DPN (DPN) and 23 matched healthy control participants (C) were enrolled. Maximal voluntary contraction (MVC) and endurance time at an intensity level of 50% of the MVC were assessed at the knee extensor muscles with an isometric dynamometer. Clinical characteristics of diabetic patients were assessed by considering a wide range of vascular and neurological parameters. DPN group had lower knee extensor muscles strength than T1D (-19%) and the C group (-37.5%). T1D group was 22% weaker when compared to the C group. Lower body muscle fatigability of DPN group was 22 and 45.5% higher than T1D and C group, respectively. T1D group possessed a higher fatigability (29.4%) compared to C group. A correlation was found between motor and sensory nerve conduction velocity and muscle strength and fatigability. Patients with T1D are characterised by both a higher fatigability and a lower muscle strength, which are aggravated by DPN. Our data suggest that factors other than nervous damage play a role in the pathogenesis of such defect.

  11. Functioning and related determinants in patients with inflammatory and idiopathic polyneuropathy

    NARCIS (Netherlands)

    Erdmann, P.G.

    2010-01-01

    The aim of the studies described in the thesis was to study the functioning of patients with CIDP, MMN, or CIAP, and the determinants of their functioning. Specific research questions were: 1. What are the functional health profiles of patients with different inflammatory polyneuropathies (CIDP and

  12. Interleukin-10 overexpression promotes Fas-ligand-dependent chronic macrophage-mediated demyelinating polyneuropathy.

    Directory of Open Access Journals (Sweden)

    Dru S Dace

    Full Text Available BACKGROUND: Demyelinating polyneuropathy is a debilitating, poorly understood disease that can exist in acute (Guillain-Barré syndrome or chronic forms. Interleukin-10 (IL-10, although traditionally considered an anti-inflammatory cytokine, has also been implicated in promoting abnormal angiogenesis in the eye and in the pathobiology of autoimmune diseases such as lupus and encephalomyelitis. PRINCIPAL FINDINGS: Overexpression of IL-10 in a transgenic mouse model leads to macrophage-mediated demyelinating polyneuropathy. IL-10 upregulates ICAM-1 within neural tissues, promoting massive macrophage influx, inflammation-induced demyelination, and subsequent loss of neural tissue resulting in muscle weakness and paralysis. The primary insult is to perineural myelin followed by secondary axonal loss. Infiltrating macrophages within the peripheral nerves demonstrate a highly pro-inflammatory signature. Macrophages are central players in the pathophysiology, as in vivo depletion of macrophages using clodronate liposomes reverses the phenotype, including progressive nerve loss and paralysis. Macrophage-mediate demyelination is dependent on Fas-ligand (FasL-mediated Schwann cell death. SIGNIFICANCE: These findings mimic the human disease chronic idiopathic demyelinating polyneuropathy (CIDP and may also promote further understanding of the pathobiology of related conditions such as acute idiopathic demyelinating polyneuropathy (AIDP or Guillain-Barré syndrome.

  13. Serum IgG levels in IV immunoglobulin treated chronic inflammatory demyelinating polyneuropathy

    NARCIS (Netherlands)

    K. Kuitwaard (Krista); P.A. van Doorn (Pieter); M. Vermeulen (Marinus); L.H. van den Berg (Leonard); E. Brusse (Esther); A.J. Kooj (Anneke); W.L. van der Pol (Ludo); I.N. van Schaik (Ivo); N.C. Notermans (Nicolette); A.P. Tio-Gillen (Anne); W. van Rijs (Wouter); T. van Gelder (Teun); B.C. Jacobs (Bart)

    2013-01-01

    textabstractObjective: To determine the variability of serum IgG in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Methods: All 25 CIDP patients had active but stable disease and were treated with individually optimised fixed dose IVIg regimens. IgG was measured by

  14. Serum IgG levels in IV immunoglobulin treated chronic inflammatory demyelinating polyneuropathy

    NARCIS (Netherlands)

    Kuitwaard, Krista; van Doorn, Pieter A.; Vermeulen, Marinus; van den Berg, Leonard H.; Brusse, Esther; van der Kooi, Anneke J.; van der Pol, W.-Ludo; van Schaik, Ivo N.; Notermans, Nicolette; Tio-Gillen, Anne P.; van Rijs, Wouter; van Gelder, Teun; Jacobs, Bart C.

    2013-01-01

    Objective To determine the variability of serum IgG in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Methods All 25 CIDP patients had active but stable disease and were treated with individually optimised fixed dose IVIg regimens. IgG was measured by turbidimetry and

  15. The Dutch neuromuscular database CRAMP (Computer Registry of All Myopathies and Polyneuropathies) : Development and preliminary data

    NARCIS (Netherlands)

    van Engelen, B. G. M.; van Veenendaal, H.; van Doorn, P. A.; van der Hoeven, J. H.; Janssen, N. G.; Notermans, N. C.; van Schaik, I. N.; Visser, L. H.; Verschuuren, J. J. G. M.

    Each of the various neuromuscular diseases is rare. Consequently, solid epidemiological data are not available and it is often difficult to find sufficient patients for studies. For this reason, the Dutch neuromuscular database, CRAMP (Computer Registry of All Myopathies and Polyneuropathies), was

  16. The Dutch neuromuscular database CRAMP (Computer Registry of All Myopathies and Polyneuropathies): development and preliminary data.

    NARCIS (Netherlands)

    Engelen, B.G.M. van; Veenendaal, H. van; Doorn, P.A. van; Faber, C.G.; Hoeven, J.H. van; Janssen, N.G.; Notermans, N.C.; Schaik, I.N. van; Visser, L.H.; Verschuuren, J.J.

    2007-01-01

    Each of the various neuromuscular diseases is rare. Consequently, solid epidemiological data are not available and it is often difficult to find sufficient patients for studies. For this reason, the Dutch neuromuscular database, CRAMP (Computer Registry of All Myopathies and Polyneuropathies), was

  17. Symptom scoring systems to diagnose distal polyneuropathy in diabetes : the Diabetic Neuropathy Symptom score

    NARCIS (Netherlands)

    Meijer, J.W.G.; Smit, A.J.; van Sonderen, E.; Groothoff, J.W.; Eisma, W.H.; Links, T.P.

    2002-01-01

    AIMS: To provide one of the diagnostic categories for distal diabetic polyneuro-pathy,several symptom scoring systems are available, which are often extensive andlack in validation. We validated a new four-item Diabetic Neuropathy Symptom (DNS) scorefor diagnosing distal diabetic polyneuropathy.

  18. [Characteristics of pain syndrome in patients with upper limbs occupational polyneuropathies].

    Science.gov (United States)

    Kochetova, O A; Mal'kova, N Yu

    2015-01-01

    Pain syndrome accompanies various diseases of central and peripheral nervous system--that is one of the most important problems in contemporary neurology. Many scientists are in search for effective diagnostic and therapeutic tools. The article covers characteristics of the pain syndrome and its mechanisms in patients with upper limbs occupational polyneuropathies.

  19. Evidence-based interventional pain medicine according to clinical diagnoses. 18. Painful diabetic polyneuropathy.

    NARCIS (Netherlands)

    Pluijms, W.A.; Huygen, F.; Cheng, J.; Mekhail, N.; Kleef, M. van; Zundert, J. van; Dongen, R.T.M. van

    2011-01-01

    In the industrialized world, polyneuropathy induced by diabetes mellitus (DM) is one of the most prevalent forms of neuropathy. Diabetic neuropathy can result from a direct toxic effect of glucose on nerve cells. Additionally, the damage of the nerve structures (central and peripheral) is

  20. Clinical diagnosis of diabetic polyneuropathy with the diabetic neuropathy symptom and diabetic neuropathy examination scores

    NARCIS (Netherlands)

    Meijer, J.W.; Lefrandt, J.D.; Links, T.P.; Smit, J.A.; Stewart, R.E.; van der Hoeven, J.H.; Hoogenberg, K.

    OBJECTIVE - To evaluate the discriminative power of the Diabetic Neuropathy Symptom (DNS) and Diabetic Neuropathy Examination (DNE) scores for diagnosing diabetic polyneuropathy (PNP), as well as their relation with cardiovascular autonomic function testing (cAFT) and electro-diagnostic studies

  1. Back to basics in diagnosing diabetic polyneuropathy with the tuning fork!

    NARCIS (Netherlands)

    Meijer, JWG; Smit, AJ; Lefrandt, JD; van der Hoeven, JH; Hoogenberg, K; Links, TP

    OBJECTIVE- Several national and international scoring systems are used to diagnose diabetic polyneuropathy (PNP). The variety in these scores and the lack of data on validity and predictive value has led to a comparison and validation of the scores with clinical standards for PNP to determine the

  2. 'Numbness of the feet' is a poor indicator for polyneuropathy in Type 2 diabetic patients

    NARCIS (Netherlands)

    Franse, LV; Valk, GD; Dekker, Janny; Heine, RJ; van Eijk, JTM

    Aims To identify neuropathic sensory symptoms associated with a clinical neurological examination (CNE) and to investigate whether these symptoms could be used as a diagnostic or screening tool for diabetic polyneuropathy in general practice. Methods Five hundred and eighty-eight patients with Type

  3. A Dutch kindred with familial amyloidotic polyneuropathy associated with the transthyretin Cys 114 mutant

    NARCIS (Netherlands)

    Haagsma, EB; Post, JG; DeJager, AEJ; Nikkels, PGJ; Hamel, BCJ; Hazenberg, BPC

    A Dutch kindred with transthyretin Cys 114 related familial amyloidotic polyneuropathy is reported. The finding of early involvement of the heart is of great concern and of special relevance to the optimal timing for liver transplantation. To date, the variant had only been reported to be present in

  4. Anti-beta-tubulin antibodies have no diagnostic value in patients with chronic inflammatory demyelinating polyneuropathy

    NARCIS (Netherlands)

    van Schaik, I. N.; Vermeulen, M.; van Doorn, P. A.; Brand, A.

    1995-01-01

    High-titre anti-beta-tubulin antibodies were recently reported to occur in over 50% of sera from patients with chronic inflammatory demyelinating polyneuropathy (CIDP). It was concluded that these antibodies may help to distinguish CIDP from other neuropathies and that they are diagnostically

  5. Polyneuropathy in a patient with malignant pleural mesothelioma: a paraneoplastic syndrome

    DEFF Research Database (Denmark)

    Bech, C.; Sørensen, Jens Benn

    2008-01-01

    Paraneoplastic syndromes have only been reported in malignant pleural mesothelioma (MPM) in a few cases. In this case, we describe a 57-year-old man with MPM who developed sensory-motor polyneuropathy 18 days after diagnosis. Thorough endocrinological, neurological, and paraclinical examinations...

  6. Peripheral treatment with enoxaparin exacerbates amyloid plaque pathology in Tg2576 mice.

    Science.gov (United States)

    Cui, Hao; King, Anna E; Jacobson, Glenn A; Small, David H

    2017-04-01

    Alzheimer's disease (AD) is a complex, progressive neurological disorder characterized by the formation of extracellular amyloid plaques composed of β-amyloid protein (Aβ), the key component in pathogenesis of AD. Peripheral administration of enoxaparin (ENO) reportedly reduces the level of Aβ and the amyloid plaques in the cortex of amyloid precursor protein (APP) transgenic mice. However, the exact mechanism of these effects is unclear. Our previous studies indicated that ENO can inhibit APP processing to Aβ in primary cortical cells from Tg2576 mice by downregulating BACE1 levels. This study examines whether ENO-induced reduction of amyloid load is due to the decreased APP processing to Aβ in Tg2576 mice. Surprisingly, our results indicated that ENO significantly increases the Aβ42/Aβ40 ratio in cortex and enhances the amyloid plaque load in both cortex and hippocampus, although overall APP processing was not influenced by ENO. Moreover, ENO stimulated the aggregation of both Aβ40 and Aβ42 in vitro. Although ENO has been reported to improve cognition in vivo and has potential as a therapeutic agent for AD, the results from our study suggest that ENO can exacerbate the amyloid pathology, and the strategy of using ENO for the treatment of AD may require further assessment. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Amyloid Goiter Secondary to Ulcerative Colitis

    Directory of Open Access Journals (Sweden)

    Bunyamin Aydin

    2016-01-01

    Full Text Available Diffuse amyloid goiter (AG is an entity characterized by the deposition of amyloid in the thyroid gland. AG may be associated with either primary or secondary amyloidosis. Secondary amyloidosis is rarely caused by inflammatory bowel diseases. Secondary amyloidosis is relatively more common in the patients with Crohn’s disease, whereas it is highly rare in patients with ulcerative colitis. Diffuse amyloid goiter caused by ulcerative colitis is also a rare condition. In the presence of amyloid in the thyroid gland, medullary thyroid cancer should be kept in mind in the differential diagnosis. Imaging techniques and biochemical tests are not very helpful in the diagnosis of secondary amyloid goiter and the definitive diagnosis is established based on the histopathologic analysis and histochemical staining techniques. In this report, we present a 35-year-old male patient with diffuse amyloid goiter caused by secondary amyloidosis associated with ulcerative colitis.

  8. Amyloid myopathy: a diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Heli Tuomaala

    2009-08-01

    Full Text Available Amyloid myopathy (AM is a rare manifestation of primary systemic amyloidosis (AL. Like inflammatory myopathies, it presents with proximal muscle weakness and an increased creatine kinase level. We describe a case of AL with severe, rapidly progressive myopathy as the initial symptom. The clinical manifestation and muscle biopsy were suggestive of inclusion body myositis. AM was not suspected until amyloidosis was seen in the gastric mucosal biopsy. The muscle biopsy was then re-examined more specifically, and Congo red staining eventually showed vascular and interstitial amyloid accumulation, which led to a diagnosis of AM. The present case illustrates the fact that the clinical picture of AM can mimic that of inclusion body myositis.

  9. Working hand syndrome: A new definition of non-classified polyneuropathy condition.

    Science.gov (United States)

    Özdemir, Gökhan

    2017-06-01

    The aim of this paper was to define an unexplained non-classified polyneuropathy condition as a new neurological disease. This new diagnosis of occupation related polyneuropathy has been named as "WORKING HAND SYNDROME (WHS)."This study collected and compared clinic and electrophysiological analyze data from healthy controls, WHS patients, carpal tunnel syndrome (CTS) patients and polyneuropathy patients. The WHS patients presented to the clinic with pain, numbness, tingling, and burning sensations in their hands that increased significantly during rest and nighttime. However, there was no weakness in the muscles, and the deep tendon reflexes were normal in this disease. The patients had all been working in physically demanding jobs requiring the use of their hands/arms for at least 1 year, but no vibrating tools were used by the patients. All of the cases were men. I supposed that overload caused by an action repeated chronically by the hand/arm may impair the sensory nerves in mentioned hand/arm. In patients with these complaints, for a definitive diagnosis, similar diseases must be excluded. Nonetheless, the specific electrophysiological finding that the sural nerves are normal on the lower sides, as well as the occurrence of sensory axonal polyneuropathy in the sensory nerves without a significant effect on velocity and latency in the work-ups of the upper extremity are enough to make a diagnosis.In conclusion, WHS has been defined as a polyneuropathy and occupational disease. Patients with WHS present with pain, numbness, tingling, and burning sensations in their hands that increases significantly during rest and nighttime. They also use their arms/hands for jobs that require heavy labor. The neurological examinations of patients with WHS are normal. Only the sensory nerves in the upper extremities are affected. This article is suggested to serve as a resource for patients, health care professionals, and members of the neurology community at large.

  10. Sympathetic re-innervation of myocardium after liver transplant in the hereditary amyloid neuropathy; Reinnervation sympathique du myocarde apres transplantation hepatique dans la neuropathie amyloide hereditaire

    Energy Technology Data Exchange (ETDEWEB)

    Delahaye, N.; Le Guludec, D. [Medecine Nucleaire, Hopital Bichat, Paris (France); Slama, M. [Cardiologie, Hopital A.Beclere, Paris (France); Guyen, C.N. [SHFJ, DSV-CEA, Orsay (France); Dinanian, S. [Cardiologie, Hopital A.Beclere, Paris (France); Merlet, P. [SHFJ, DSV-CEA, Orsay (France)

    1997-12-31

    The hereditary amyloid neuropathy (HAN) is characterized by a progressive sensory-motor poly-neuropathy and a dysautonomia with myocardium sympathetic denervation. This is established by MIBL scintigraphy and may enhance the troubles of conduction and of cardiac rhythm. The amyloid deposits are constituted of anomalous pre-albumin fabricated by liver. The hepatic transplant (HT) is the only known treatment. Four patients (GI: 39 {+-} 5 years) have been studied by MIBG scintigraphy, 2.2 {+-} 0.7 years after HT, and compared with 12 patients (GII: 39 {+-} 12 years) studied before HT. The left ventricular function, the coronary arteries and the at-rest scintigraphy with thallium were normal for all of them. The cardiac capture of MIBG, evaluated by the cardio-mediastinal activity ratio (C/M), measured on an anterior thoracic planar acquisition performed 4 hours after the intravenous injection of 300 MBq, was higher for GI than for GII (1.49 {+-} 0.12 vs 1.29 {+-} 0.13, p 0.02). The washouts (4 h / 20 min) were not different. In tomography, the patients of GI presented focal anomalies with a more-or-less extended apical defect, a satisfying fixation of the basal half of the anterior wall, more-or-less overflowing the septal and lateral walls, and for 2 patients, a satisfying inferior fixation. On the contrary, 9/12 patients of GII have had a diffuse absence of fixation, the other three heaving a satisfying antero-basal fixation ({chi}{sup 2}, p = 0.05). The results are not explained by difference of severity or evolution duration of HAN. Thus, it appears that there exists a sympathetic re-innervation of myocardium after HT in the HAN, debuting by the heart base, similarly with the effect of anatomic interruption of innervation in cardiac transplants

  11. Depressive symptoms accelerate cognitive decline in amyloid-positive MCI patients

    International Nuclear Information System (INIS)

    Brendel, Matthias; Xiong, Guoming; Delker, Andreas; Pogarell, Oliver; Bartenstein, Peter; Rominger, Axel

    2015-01-01

    Late-life depression even in subsyndromal stages is strongly associated with Alzheimer's disease (AD). Furthermore, brain amyloidosis is an early biomarker in subjects who subsequently suffer from AD and can be sensitively detected by amyloid PET. Therefore, we aimed to compare amyloid load and glucose metabolism in subsyndromally depressed subjects with mild cognitive impairment (MCI). [ 18 F]AV45 PET, [ 18 F]FDG PET and MRI were performed in 371 MCI subjects from the Alzheimer's Disease Neuroimaging Initiative Subjects were judged β-amyloid-positive (Aβ+; 206 patients) or β-amyloid-negative (Aβ-; 165 patients) according to [ 18 F]AV45 PET. Depressive symptoms were assessed by the Neuropsychiatric Inventory Questionnaire depression item 4. Subjects with depressive symptoms (65 Aβ+, 41 Aβ-) were compared with their nondepressed counterparts. Conversion rates to AD were analysed (mean follow-up time 21.5 ± 9.1 months) with regard to coexisting depressive symptoms and brain amyloid load. Aβ+ depressed subjects showed large clusters with a higher amyloid load in the frontotemporal and insular cortices (p < 0.001) with coincident hypermetabolism (p < 0.001) in the frontal cortices than nondepressed subjects. Faster progression to AD was observed in subjects with depressive symptoms (p < 0.005) and in Aβ+ subjects (p < 0.001). Coincident depressive symptoms additionally shortened the conversion time in all Aβ+ subjects (p < 0.005) and to a greater extent in those with a high amyloid load (p < 0.001). Our results clearly indicate that Aβ+ MCI subjects with depressive symptoms have an elevated amyloid load together with relative hypermetabolism of connected brain areas compared with cognitively matched nondepressed individuals. MCI subjects with high amyloid load and coexistent depressive symptoms are at high risk of faster conversion to AD. (orig.)

  12. Amyloid polymorphisms constitute distinct clouds of conformational variants in different etiological subtypes of Alzheimer's disease.

    Science.gov (United States)

    Rasmussen, Jay; Mahler, Jasmin; Beschorner, Natalie; Kaeser, Stephan A; Häsler, Lisa M; Baumann, Frank; Nyström, Sofie; Portelius, Erik; Blennow, Kaj; Lashley, Tammaryn; Fox, Nick C; Sepulveda-Falla, Diego; Glatzel, Markus; Oblak, Adrian L; Ghetti, Bernardino; Nilsson, K Peter R; Hammarström, Per; Staufenbiel, Matthias; Walker, Lary C; Jucker, Mathias

    2017-12-05

    The molecular architecture of amyloids formed in vivo can be interrogated using luminescent conjugated oligothiophenes (LCOs), a unique class of amyloid dyes. When bound to amyloid, LCOs yield fluorescence emission spectra that reflect the 3D structure of the protein aggregates. Given that synthetic amyloid-β peptide (Aβ) has been shown to adopt distinct structural conformations with different biological activities, we asked whether Aβ can assume structurally and functionally distinct conformations within the brain. To this end, we analyzed the LCO-stained cores of β-amyloid plaques in postmortem tissue sections from frontal, temporal, and occipital neocortices in 40 cases of familial Alzheimer's disease (AD) or sporadic (idiopathic) AD (sAD). The spectral attributes of LCO-bound plaques varied markedly in the brain, but the mean spectral properties of the amyloid cores were generally similar in all three cortical regions of individual patients. Remarkably, the LCO amyloid spectra differed significantly among some of the familial and sAD subtypes, and between typical patients with sAD and those with posterior cortical atrophy AD. Neither the amount of Aβ nor its protease resistance correlated with LCO spectral properties. LCO spectral amyloid phenotypes could be partially conveyed to Aβ plaques induced by experimental transmission in a mouse model. These findings indicate that polymorphic Aβ-amyloid deposits within the brain cluster as clouds of conformational variants in different AD cases. Heterogeneity in the molecular architecture of pathogenic Aβ among individuals and in etiologically distinct subtypes of AD justifies further studies to assess putative links between Aβ conformation and clinical phenotype.

  13. Depressive symptoms accelerate cognitive decline in amyloid-positive MCI patients

    Energy Technology Data Exchange (ETDEWEB)

    Brendel, Matthias; Xiong, Guoming; Delker, Andreas [University of Munich, Department of Nuclear Medicine, Munich (Germany); Pogarell, Oliver [University of Munich, Department of Psychiatry, Munich (Germany); Bartenstein, Peter; Rominger, Axel [University of Munich, Department of Nuclear Medicine, Munich (Germany); Munich Cluster for Systems Neurology (SyNergy), Munich (Germany); Collaboration: for the Alzheimer' s Disease Neuroimaging Initiative

    2015-04-01

    Late-life depression even in subsyndromal stages is strongly associated with Alzheimer's disease (AD). Furthermore, brain amyloidosis is an early biomarker in subjects who subsequently suffer from AD and can be sensitively detected by amyloid PET. Therefore, we aimed to compare amyloid load and glucose metabolism in subsyndromally depressed subjects with mild cognitive impairment (MCI). [{sup 18}F]AV45 PET, [{sup 18}F]FDG PET and MRI were performed in 371 MCI subjects from the Alzheimer's Disease Neuroimaging Initiative Subjects were judged β-amyloid-positive (Aβ+; 206 patients) or β-amyloid-negative (Aβ-; 165 patients) according to [{sup 18}F]AV45 PET. Depressive symptoms were assessed by the Neuropsychiatric Inventory Questionnaire depression item 4. Subjects with depressive symptoms (65 Aβ+, 41 Aβ-) were compared with their nondepressed counterparts. Conversion rates to AD were analysed (mean follow-up time 21.5 ± 9.1 months) with regard to coexisting depressive symptoms and brain amyloid load. Aβ+ depressed subjects showed large clusters with a higher amyloid load in the frontotemporal and insular cortices (p < 0.001) with coincident hypermetabolism (p < 0.001) in the frontal cortices than nondepressed subjects. Faster progression to AD was observed in subjects with depressive symptoms (p < 0.005) and in Aβ+ subjects (p < 0.001). Coincident depressive symptoms additionally shortened the conversion time in all Aβ+ subjects (p < 0.005) and to a greater extent in those with a high amyloid load (p < 0.001). Our results clearly indicate that Aβ+ MCI subjects with depressive symptoms have an elevated amyloid load together with relative hypermetabolism of connected brain areas compared with cognitively matched nondepressed individuals. MCI subjects with high amyloid load and coexistent depressive symptoms are at high risk of faster conversion to AD. (orig.)

  14. Amyloid imaging: the court of public opinion.

    Science.gov (United States)

    Lerner, Alan J

    2013-09-24

    Human amyloid imaging is one of the great recent translational medicine stories. Beginning with the recognition that Thioflavin T derivatives could be used as PET tracers, through development of Pittsburgh compound B, to Food and Drug Administration (FDA) approval of Florbetapir in 2012, human amyloid imaging has held great promise to allow in vivo inclusive diagnosis of Alzheimer disease (AD), even though the first principle of amyloid PET is that it functions as a surrogate for β-amyloid pathology, and not necessarily as a surrogate for the diagnosis of AD.(1,2.)

  15. Acute inflammatory demyelinating polyneuropathy associated with pegylated interferon α 2a therapy for chronic hepatitis C virus infection

    OpenAIRE

    Khiani, Vijay; Kelly, Thomas; Shibli, Adeel; Jensen, Donald; Mohanty, Smruti R

    2008-01-01

    The combination of pegylated interferon (Peg-IFN) and ribavirin is the standard of care for chronic hepatitis C virus (HCV) infection treatment. In general, common side effects related to this combination therapy are mild and are very well tolerated. However, peripheral neuropathy including demyelinating polyneuropathy related to Peg-IFN is extremely rare. We present the first case of an acute inflammatory demyelinating polyneuropathy (AIDP) associated with Peg-IFN-α 2a (Pegasys) after 16 wk ...

  16. Why are Functional Amyloids Non-Toxic in Humans?

    Directory of Open Access Journals (Sweden)

    Matthew P. Jackson

    2017-09-01

    Full Text Available Amyloids were first identified in association with amyloidoses, human diseases in which proteins and peptides misfold into amyloid fibrils. Subsequent studies have identified an array of functional amyloid fibrils that perform physiological roles in humans. Given the potential for the production of toxic species in amyloid assembly reactions, it is remarkable that cells can produce these functional amyloids without suffering any obvious ill effect. Although the precise mechanisms are unclear, there are a number of ways in which amyloid toxicity may be prevented. These include regulating the level of the amyloidogenic peptides and proteins, minimising the production of prefibrillar oligomers in amyloid assembly reactions, sequestrating amyloids within membrane bound organelles, controlling amyloid assembly by other molecules, and disassembling the fibrils under physiological conditions. Crucially, a better understanding of how toxicity is avoided in the production of functional amyloids may provide insights into the prevention of amyloid toxicity in amyloidoses.

  17. Antibodies to human serum amyloid P component eliminate visceral amyloid deposits.

    Science.gov (United States)

    Bodin, Karl; Ellmerich, Stephan; Kahan, Melvyn C; Tennent, Glenys A; Loesch, Andrzej; Gilbertson, Janet A; Hutchinson, Winston L; Mangione, Palma P; Gallimore, J Ruth; Millar, David J; Minogue, Shane; Dhillon, Amar P; Taylor, Graham W; Bradwell, Arthur R; Petrie, Aviva; Gillmore, Julian D; Bellotti, Vittorio; Botto, Marina; Hawkins, Philip N; Pepys, Mark B

    2010-11-04

    Accumulation of amyloid fibrils in the viscera and connective tissues causes systemic amyloidosis, which is responsible for about one in a thousand deaths in developed countries. Localized amyloid can also have serious consequences; for example, cerebral amyloid angiopathy is an important cause of haemorrhagic stroke. The clinical presentations of amyloidosis are extremely diverse and the diagnosis is rarely made before significant organ damage is present. There is therefore a major unmet need for therapy that safely promotes the clearance of established amyloid deposits. Over 20 different amyloid fibril proteins are responsible for different forms of clinically significant amyloidosis and treatments that substantially reduce the abundance of the respective amyloid fibril precursor proteins can arrest amyloid accumulation. Unfortunately, control of fibril-protein production is not possible in some forms of amyloidosis and in others it is often slow and hazardous. There is no therapy that directly targets amyloid deposits for enhanced clearance. However, all amyloid deposits contain the normal, non-fibrillar plasma glycoprotein, serum amyloid P component (SAP). Here we show that administration of anti-human-SAP antibodies to mice with amyloid deposits containing human SAP triggers a potent, complement-dependent, macrophage-derived giant cell reaction that swiftly removes massive visceral amyloid deposits without adverse effects. Anti-SAP-antibody treatment is clinically feasible because circulating human SAP can be depleted in patients by the bis-d-proline compound CPHPC, thereby enabling injected anti-SAP antibodies to reach residual SAP in the amyloid deposits. The unprecedented capacity of this novel combined therapy to eliminate amyloid deposits should be applicable to all forms of systemic and local amyloidosis.

  18. Anti-amyloid treatments in Alzheimer's disease.

    Science.gov (United States)

    Sapra, Mamta; Kim, Kye Y

    2009-06-01

    Alzheimer's disease is one of the most challenging threats to the healthcare system in society. One of the main characteristic of Alzheimer's disease (AD) pathology is formation of amyloid plaques from accumulation of amyloid beta peptide. The therapeutic agents that are currently available for AD including acetylcholinesterase inhibitors (AchEIs) and the N-methyl-D-aspartate (NMDA) antagonist are focused on improving the symptoms and do not revert the progression of the disease. This limitation coupled with the burgeoning increase in the prevalence of AD and resultant impact on healthcare economics calls for more substantial treatments for AD. According to the leading amyloid hypothesis, cleavage of amyloid precursor protein to release amyloid beta peptide is the critical event in pathogenesis of Alzheimer's disease. Recently treatment strategies have been focused on modifying the formation, clearance and accumulation of neurotoxic amyloid beta peptide. This article reviews different therapeutic approaches that have been investigated to target amyloid beta ranging from secretase modulators, antiaggregation agents to amyloid immunotherapy. Authors review the different novel drugs which are in clinical trials.

  19. Carbon nanospecies affecting amyloid formation

    Czech Academy of Sciences Publication Activity Database

    Holubová, Monika; Konefal, Rafal; Morávková, Zuzana; Zhigunov, Alexander; Svoboda, Jan; Pop-Georgievski, Ognen; Hromádková, Jiřina; Groborz, Ondřej; Štěpánek, Petr; Hrubý, Martin

    2017-01-01

    Roč. 7, č. 85 (2017), s. 53887-53898 ISSN 2046-2069 R&D Projects: GA MŠk(CZ) LM2015064; GA MZd(CZ) NV16-30544A; GA ČR(CZ) GA16-03156S; GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LO1507 Grant - others:OPPK(XE) CZ.2.16/3.1.00/21545 Program:OPPK Institutional support: RVO:61389013 Keywords : amyloid fibril * nanodiamond * fullerene Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 3.108, year: 2016

  20. Chiral recognition in amyloid fiber growth.

    Science.gov (United States)

    Torbeev, Vladimir; Grogg, Marcel; Ruiz, Jérémy; Boehringer, Régis; Schirer, Alicia; Hellwig, Petra; Jeschke, Gunnar; Hilvert, Donald

    2016-05-01

    Insoluble amyloid fibers represent a pathological signature of many human diseases. To treat such diseases, inhibition of amyloid formation has been proposed as a possible therapeutic strategy. d-Peptides, which possess high proteolytic stability and lessened immunogenicity, are attractive candidates in this context. However, a molecular understanding of chiral recognition phenomena for d-peptides and l-amyloids is currently incomplete. Here we report experiments on amyloid growth of individual enantiomers and their mixtures for two distinct polypeptide systems of different length and structural organization: a 44-residue covalently-linked dimer derived from a peptide corresponding to the [20-41]-fragment of human β2-microglobulin (β2m) and the 99-residue full-length protein. For the dimeric [20-41]β2m construct, a combination of electron paramagnetic resonance of nitroxide-labeled constructs and (13) C-isotope edited FT-IR spectroscopy of (13) C-labeled preparations was used to show that racemic mixtures precipitate as intact homochiral fibers, i.e. undergo spontaneous Pasteur-like resolution into a mixture of left- and right-handed amyloids. In the case of full-length β2m, the presence of the mirror-image d-protein affords morphologically distinct amyloids that are composed largely of enantiopure domains. Removal of the l-component from hybrid amyloids by proteolytic digestion results in their rapid transformation into characteristic long straight d-β2m amyloids. Furthermore, the full-length d-enantiomer of β2m was found to be an efficient inhibitor of l-β2m amyloid growth. This observation highlights the potential of longer d-polypeptides for future development into inhibitors of amyloid propagation. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

  1. Amyloid beta peptide immunotherapy in Alzheimer disease.

    Science.gov (United States)

    Delrieu, J; Ousset, P J; Voisin, T; Vellas, B

    2014-12-01

    Recent advances in the understanding of Alzheimer's disease pathogenesis have led to the development of numerous compounds that might modify the disease process. Amyloid β peptide represents an important molecular target for intervention in Alzheimer's disease. The main purpose of this work is to review immunotherapy studies in relation to the Alzheimer's disease. Several types of amyloid β peptide immunotherapy for Alzheimer's disease are under investigation, active immunization and passive administration with monoclonal antibodies directed against amyloid β peptide. Although immunotherapy approaches resulted in clearance of amyloid plaques in patients with Alzheimer's disease, this clearance did not show significant cognitive effect for the moment. Currently, several amyloid β peptide immunotherapy approaches are under investigation but also against tau pathology. Results from amyloid-based immunotherapy studies in clinical trials indicate that intervention appears to be more effective in early stages of amyloid accumulation in particular solanezumab with a potential impact at mild Alzheimer's disease, highlighting the importance of diagnosing Alzheimer's disease as early as possible and undertaking clinical trials at this stage. In both phase III solanezumab and bapineuzumab trials, PET imaging revealed that about a quarter of patients lacked fibrillar amyloid pathology at baseline, suggesting that they did not have Alzheimer's disease in the first place. So a new third phase 3 clinical trial for solanezumab, called Expedition 3, in patients with mild Alzheimer's disease and evidence of amyloid burden has been started. Thus, currently, amyloid intervention is realized at early stage of the Alzheimer's disease in clinical trials, at prodromal Alzheimer's disease, or at asymptomatic subjects or at risk to develop Alzheimer's disease and or at asymptomatic subjects with autosomal dominant mutation. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Overview of the pathogenesis and treatment of chronic inflammatory demyelinating polyneuropathy with intravenous immunoglobulins

    Directory of Open Access Journals (Sweden)

    Mohamed Mahdi-Rogers

    2010-03-01

    Full Text Available Mohamed Mahdi-Rogers, Yusuf A RajaballyNeuromuscular Clinic, Department of Neurology, University Hospitals of Leicester, Leicester, UKAbstract: Chronic inflammatory demyelinating polyneuropathy (CIDP is an acquired heterogeneous disorder of immune origin affecting the peripheral nerves, causing motor weakness and sensory symptoms and signs. The precise pathophysiology of CIDP remains uncertain although B and T cell mechanisms are believed to be implicated. Intravenous immunoglobulins (IVIg have been shown in a number of trials to be an effective treatment for CIDP. IVIg is thought to exert its immunomodulatory effects by affecting several components of the immune system including B-cells, T-cells, macrophages and complement. This article provides an overview of the pathogenesis of CIDP and of its treatment with IVIg.Keywords: chronic inflammatory demyelinating polyneuropathy, intravenous immunoglobulin, pathogenesis, treatment

  3. Post bariatric Surgery Acute Axonal Polyneuropathy: Doing Your Best is Not Always Enough.

    Science.gov (United States)

    Yasawy, Zakia Mohammad; Hassan, Ali

    2017-01-01

    Neurological complications are frequently recognized with weight reduction surgeries for morbid obesity. The spectrum of peripheral neuropathies complicating the weight loss surgery is wide, and among them, the acute axonal peripheral neuropathy resembling Guillain-Barre syndrome is rare and only less than a dozen cases are reported. We present three cases, which after bariatric surgery developed acute polyneuropathy that rapidly progressed over 4 weeks from the onset. All patients responded to aggressive parenteral Vitamin B1 and B12 replacement therapy. These cases highlight the fact that bariatric surgery although is a promising option to treat morbid obesity; it is certainly not devoid of potential neurological complications due to micronutrient deficiencies. Delay in the diagnosis of acute polyneuropathy may worsen its long-term sequelae. A multidisciplinary team management with careful nutritional monitoring at regular interval is crucial in all patients for early recognition and intervention to avoid these complications after bariatric surgery.

  4. General amyloid inhibitors? A critical examination of the inhibition of IAPP amyloid formation by inositol stereoisomers.

    Directory of Open Access Journals (Sweden)

    Hui Wang

    Full Text Available Islet amyloid polypeptide (IAPP or amylin forms amyloid deposits in the islets of Langerhans; a process that is believed to contribute to the progression of type 2 diabetes and to the failure of islet transplants. An emerging theme in amyloid research is the hypothesis that the toxic species produced during amyloid formation by different polypeptides share common features and exert their effects by common mechanisms. If correct, this suggests that inhibitors of amyloid formation by one polypeptide might be effective against other amyloidogenic sequences. IAPP and Aβ, the peptide responsible for amyloid formation in Alzheimer's disease, are particularly interesting in this regard as they are both natively unfolded in their monomeric states and share some common characteristics. Comparatively little effort has been expended on the design of IAPP amyloid inhibitors, thus it is natural to inquire if Aβ inhibitors are effective against IAPP, especially since no IAPP inhibitors have been clinically approved. A range of compounds inhibit Aβ amyloid formation, including various stereoisomers of inositol. Myo-, scyllo-, and epi-inositol have been shown to induce conformational changes in Aβ and prevent Aβ amyloid fibril formation by stabilizing non-fibrillar β-sheet structures. We investigate the ability of inositol stereoisomers to inhibit amyloid formation by IAPP. The compounds do not induce a conformational change in IAPP and are ineffective inhibitors of IAPP amyloid formation, although some do lead to modest apparent changes in IAPP amyloid fibril morphology. Thus not all classes of Aβ inhibitors are effective against IAPP. This work provides a basis of comparison to work on polyphenol based inhibitors of IAPP amyloid formation and helps provide clues as to the features which render them effective. The study also helps provide information for further efforts in rational inhibitor design.

  5. General Amyloid Inhibitors? A Critical Examination of the Inhibition of IAPP Amyloid Formation by Inositol Stereoisomers

    Science.gov (United States)

    Wang, Hui; Raleigh, Daniel P.

    2014-01-01

    Islet amyloid polypeptide (IAPP or amylin) forms amyloid deposits in the islets of Langerhans; a process that is believed to contribute to the progression of type 2 diabetes and to the failure of islet transplants. An emerging theme in amyloid research is the hypothesis that the toxic species produced during amyloid formation by different polypeptides share common features and exert their effects by common mechanisms. If correct, this suggests that inhibitors of amyloid formation by one polypeptide might be effective against other amyloidogenic sequences. IAPP and Aβ, the peptide responsible for amyloid formation in Alzheimer's disease, are particularly interesting in this regard as they are both natively unfolded in their monomeric states and share some common characteristics. Comparatively little effort has been expended on the design of IAPP amyloid inhibitors, thus it is natural to inquire if Aβ inhibitors are effective against IAPP, especially since no IAPP inhibitors have been clinically approved. A range of compounds inhibit Aβ amyloid formation, including various stereoisomers of inositol. Myo-, scyllo-, and epi-inositol have been shown to induce conformational changes in Aβ and prevent Aβ amyloid fibril formation by stabilizing non-fibrillar β-sheet structures. We investigate the ability of inositol stereoisomers to inhibit amyloid formation by IAPP. The compounds do not induce a conformational change in IAPP and are ineffective inhibitors of IAPP amyloid formation, although some do lead to modest apparent changes in IAPP amyloid fibril morphology. Thus not all classes of Aβ inhibitors are effective against IAPP. This work provides a basis of comparison to work on polyphenol based inhibitors of IAPP amyloid formation and helps provide clues as to the features which render them effective. The study also helps provide information for further efforts in rational inhibitor design. PMID:25260075

  6. Comorbidity of psychiatric disorders and symmetric distal polyneuropathy among type II diabetic outpatients

    OpenAIRE

    Moreira,R.O.; Papelbaum,M.; Fontenelle,L.F.; Appolinario,J.C.; Ellinger,V.C.M.; Coutinho,W.F.; Zagury,L.

    2007-01-01

    The objective of the present study was to establish the frequency of psychiatric comorbidity in a sample of diabetic patients with symmetric distal polyneuropathy (SDPN). Sixty-five patients with type 2 diabetes mellitus were selected consecutively to participate in the study at Instituto Estadual de Diabetes e Endocrinologia. All patients were submitted to a complete clinical and psychiatric evaluation, including the Portuguese version of the structured clinical interview for DSM-IV, the Bec...

  7. PHYTO-PHARMACEUTICAL ASSAY OF DASHAMOOLADI RASAYANA COMPOUND: A NOVEL COMPOUND FOR DIABETIC POLYNEUROPATHY

    OpenAIRE

    Niranjan Y; Shukla VJ; Baghel MS

    2011-01-01

    At least 171 million people worldwide have diabetes; among them 47% suffer from symptom of diabetic sensorimotor peripheral polyneuropathy (DSPN). Despite advances in understanding metabolic causes of neuropathy, treatments aimed at interrupting these pathological processes have been limited by side effects and lack of efficacy. Even though it is not mentioned directly in Ayurvedic literature, critical analysis of the lakshanas of DSPN gives certain insights to the role of Avarana of Vata by ...

  8. The Effects of Pulsed Electromagnetic Field Treatment in Pain Due to Diabetic Polyneuropathy

    OpenAIRE

    FEZYİOĞLU, Pervin; Özdemir, Ferda; ÖZDEMİR, Ferda; GÜLDİKEN, Sibel; BALCI, Kemal; Süt, Necdet

    2014-01-01

    Objectives: Diabetic polyneuropathy is the most common and disabled complication of diabetes mellitus. Pharmacological treatment of diabetic neuropathy is limited because of the side efects of the drugs, used in the treatment of diabetic neuropthy. Alternative treatments are also used in diabetic neuropathy. Systemic side effects of non-pharmacological treatment modalities are rare. We evaluated the value of pulsed electromagnetic field treatment in patients with pain due to diabetic polyneur...

  9. Association Between Elevated Brain Amyloid and Subsequent Cognitive Decline Among Cognitively Normal Persons.

    Science.gov (United States)

    Donohue, Michael C; Sperling, Reisa A; Petersen, Ronald; Sun, Chung-Kai; Weiner, Michael W; Aisen, Paul S

    2017-06-13

    amyloid level, was associated with higher likelihood of cognitive decline, although the findings are of uncertain clinical significance. Further research is needed to assess the clinical importance of these differences and measure longer-term associations.

  10. Neurophysiological and clinical responses to rituximab in patients with anti-MAG polyneuropathy.

    Science.gov (United States)

    Zara, Gabriella; Zambello, Renato; Ermani, M

    2011-12-01

    Rituximab treatment has shown clinical improvement in anti-myelin associated glycoprotein (MAG) polyneuropathy. We analyzed scores of clinical scales and the most sensitive electrophysiological parameters before and after immunomodulating treatment with rituximab in a group of patients affected by anti-MAG demyelinating polyneuropathy. Clinical scores, the percentage of CD20 B-lymphocytes, anti-MAG antibody titers and electrophysiological data in 7 patients with anti-MAG polyneuropathy were analyzed. The patients were examined before a cycle with rituximab, 6, 12 and 24 months after the end of the treatment. Two patients were treated with rituximab additional cycles and re-evaluated 48 months after the first treatment. There were no evident correlation between anti-MAG serum antibody titers or clinical scales and electrodiagnostic data. Significant decrease in the proportion of CD20 B-lymphocytes was observed. Significant anti-MAG antibodies titers reduction was detected after re-treatment. At follow-up, pinprik sensation and two point discrimination presented a significant improvement compared with the score before treatment. In our patients, rituximab did not improve any electrophysiological data. No correlation with anti-MAG serum antibodies course was found. With rituximab only pin sensibility improved. Rituximab re-treatment significantly reduces anti-MAG serum antibodies titers but improves only small fibers sensibility. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  11. Diabetic polyneuropathy, sensory neurons, nuclear structure and spliceosome alterations: a role for CWC22

    Directory of Open Access Journals (Sweden)

    Masaki Kobayashi

    2017-03-01

    Full Text Available Unique deficits in the function of adult sensory neurons as part of their early neurodegeneration might account for progressive polyneuropathy during chronic diabetes mellitus. Here, we provide structural and functional evidence for aberrant pre-mRNA splicing in a chronic type 1 model of experimental diabetic polyneuropathy (DPN. Cajal bodies (CBs, unique nuclear substructures involved in RNA splicing, increased in number in diabetic sensory neurons, but their expected colocalization with survival motor neuron (SMN proteins was reduced – a mislocalization described in motor neurons of spinal muscular atrophy. Small nuclear ribonucleoprotein particles (snRNPs, also participants in the spliceosome, had abnormal multiple nuclear foci unassociated with CBs, and their associated snRNAs were reduced. CWC22, a key spliceosome protein, was aberrantly upregulated in diabetic dorsal root ganglia (DRG, and impaired neuronal function. CWC22 attenuated sensory neuron plasticity, with knockdown in vitro enhancing their neurite outgrowth. Further, axonal delivery of CWC22 siRNA unilaterally to locally knock down the aberrant protein in diabetic nerves improved aspects of sensory function in diabetic mice. Collectively, our findings identify subtle but significant alterations in spliceosome structure and function, including dysregulated CBs and CWC22 overexpression, in diabetic sensory neurons that offer new ideas regarding diabetic sensory neurodegeneration in polyneuropathy.

  12. Recurrent Isolated Sixth Nerve Palsy in Relapsing-Remitting Chronic Inflammatory Demyelinating Polyneuropathy.

    Science.gov (United States)

    Al-Bustani, Najwa; Weiss, Michael D

    2015-09-01

    Chronic inflammatory demyelinating polyneuropathy (CIDP) is an immune-mediated sensory and motor demyelinating polyneuropathy that typically presents as a relapsing-remitting or progressive disorder. Cranial neuropathies infrequently occur in association with other more typical symptoms of CIDP. We report a case of CIDP with recurrent isolated sixth nerve palsy. Her physical examination showed a right sixth nerve palsy and absent deep tendon reflexes as the only indicator of her disease. Magnetic resonance imaging revealed thickening without enhancement of the trigeminal and sixth cranial nerves. Nerve conduction study (NCS) revealed a sensory and motor demyelinating polyneuropathy with conduction block and temporal dispersion in multiple nerves consistent with CIDP. Cerebrospinal fluid demonstrated albuminic-cytologic dissociation. She had a remarkable response to intravenous immunoglobulin and remains asymptomatic without any additional immunomodulating therapy. Isolated cranial neuropathies can rarely occur as the sole manifestation of relapsing-remitting CIDP. The profound demyelination found on NCS in this case demonstrates that there can be a dramatic discordance between the clinical and electrodiagnostic findings in some patients with this disorder.

  13. Human immunodeficiency virus seroconversion presenting with acute inflammatory demyelinating polyneuropathy: a case report

    Directory of Open Access Journals (Sweden)

    Sloan Derek J

    2008-12-01

    Full Text Available Abstract Introduction Acute Human Immunodeficiency Virus infection is associated with a range of neurological conditions. Guillain-Barré syndrome is a rare presentation; acute inflammatory demyelinating polyneuropathy is the commonest form of Guillain-Barré syndrome. Acute inflammatory demyelinating polyneuropathy has occasionally been reported in acute Immunodeficiency Virus infection but little data exists on frequency, management and outcome. Case presentation We describe an episode of Guillain-Barré syndrome presenting as acute inflammatory demyelinating polyneuropathy in a 30-year-old man testing positive for Immunodeficiency Virus, probably during acute seroconversion. Clinical suspicion was confirmed by cerebrospinal fluid analysis and nerve conduction studies. Rapid clinical deterioration prompted intravenous immunoglobulin therapy and early commencement of highly active anti-retroviral therapy. All symptoms resolved within nine weeks. Conclusion Unusual neurological presentations in previously fit patients are an appropriate indication for Immunodeficiency-Virus testing. Highly active anti-retroviral therapy with adequate penetration of the central nervous system should be considered as an early intervention, alongside conventional therapies such as intravenous immunoglobulin.

  14. Feasibility and acceptance of simultaneous amyloid PET/MRI

    International Nuclear Information System (INIS)

    Schuetz, Lisa; Tiepolt, Solveig; Werner, Peter; Jochimsen, Thies; Rullmann, Michael; Sattler, Bernhard; Patt, Marianne; Barthel, Henryk; Lobsien, Donald; Fritzsch, Dominik; Hoffmann, Karl-Titus; Schroeter, Matthias L.; Villringer, Arno; Berrouschot, Joerg; Saur, Dorothee; Classen, Joseph; Hesse, Swen; Sabri, Osama; Gertz, Hermann-Josef

    2016-01-01

    Established Alzheimer's disease (AD) biomarker concepts classify into amyloid pathology and neuronal injury biomarkers, while recent alternative concepts classify into diagnostic and progression AD biomarkers. However, combined amyloid positron emission tomography/magnetic resonance imaging (PET/MRI) offers the chance to obtain both biomarker category read-outs within one imaging session, with increased patient as well as referrer convenience. The aim of this pilot study was to investigate this matter for the first time. 100 subjects (age 70 ± 10 yrs, 46 female), n = 51 with clinically defined mild cognitive impairment (MCI), n = 44 with possible/probable AD dementia, and n = 5 with frontotemporal lobe degeneration, underwent simultaneous [ 18 F]florbetaben or [ 11 C]PIB PET/MRI (3 Tesla Siemens mMR). Brain amyloid load, mesial temporal lobe atrophy (MTLA) by means of the Scheltens scale, and other morphological brain pathologies were scored by respective experts. The patients/caregivers as well as the referrers were asked to assess on a five-point scale the convenience related to the one-stop-shop PET and MRI approach. In three subjects, MRI revealed temporal lobe abnormalities other than MTLA. According to the National Institute on Aging-Alzheimer's Association classification, the combined amyloid-beta PET/MRI evaluation resulted in 31 %, 45 %, and 24 % of the MCI subjects being categorized as ''MCI-unlikely due to AD'', ''MCI due to AD-intermediate likelihood'', and ''MCI due to AD-high likelihood'', respectively. 50 % of the probable AD dementia patients were categorized as ''High level of evidence of AD pathophysiological process'', and 56 % of the possible AD dementia patients as ''Possible AD dementia - with evidence of AD pathophysiological process''. With regard to the International Working Group 2 classification, 36 subjects had both positive

  15. Feasibility and acceptance of simultaneous amyloid PET/MRI.

    Science.gov (United States)

    Schütz, Lisa; Lobsien, Donald; Fritzsch, Dominik; Tiepolt, Solveig; Werner, Peter; Schroeter, Matthias L; Berrouschot, Jörg; Saur, Dorothee; Hesse, Swen; Jochimsen, Thies; Rullmann, Michael; Sattler, Bernhard; Patt, Marianne; Gertz, Hermann-Josef; Villringer, Arno; Claßen, Joseph; Hoffmann, Karl-Titus; Sabri, Osama; Barthel, Henryk

    2016-11-01

    Established Alzheimer's disease (AD) biomarker concepts classify into amyloid pathology and neuronal injury biomarkers, while recent alternative concepts classify into diagnostic and progression AD biomarkers. However, combined amyloid positron emission tomography/magnetic resonance imaging (PET/MRI) offers the chance to obtain both biomarker category read-outs within one imaging session, with increased patient as well as referrer convenience. The aim of this pilot study was to investigate this matter for the first time. 100 subjects (age 70 ± 10 yrs, 46 female), n = 51 with clinically defined mild cognitive impairment (MCI), n = 44 with possible/probable AD dementia, and n = 5 with frontotemporal lobe degeneration, underwent simultaneous [ 18 F]florbetaben or [ 11 C]PIB PET/MRI (3 Tesla Siemens mMR). Brain amyloid load, mesial temporal lobe atrophy (MTLA) by means of the Scheltens scale, and other morphological brain pathologies were scored by respective experts. The patients/caregivers as well as the referrers were asked to assess on a five-point scale the convenience related to the one-stop-shop PET and MRI approach. In three subjects, MRI revealed temporal lobe abnormalities other than MTLA. According to the National Institute on Aging-Alzheimer's Association classification, the combined amyloid-beta PET/MRI evaluation resulted in 31 %, 45 %, and 24 % of the MCI subjects being categorized as "MCI-unlikely due to AD", "MCI due to AD-intermediate likelihood", and "MCI due to AD-high likelihood", respectively. 50 % of the probable AD dementia patients were categorized as "High level of evidence of AD pathophysiological process", and 56 % of the possible AD dementia patients as "Possible AD dementia - with evidence of AD pathophysiological process". With regard to the International Working Group 2 classification, 36 subjects had both positive diagnostic and progression biomarkers. The patient/caregiver survey revealed a gain of convenience in

  16. Neuroinflammation in Lyme neuroborreliosis affects amyloid metabolism

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    Anckarsäter Henrik

    2010-06-01

    Full Text Available Abstract Background The metabolism of amyloid precursor protein (APP and β-amyloid (Aβ is widely studied in Alzheimer's disease, where Aβ deposition and plaque development are essential components of the pathogenesis. However, the physiological role of amyloid in the adult nervous system remains largely unknown. We have previously found altered cerebral amyloid metabolism in other neuroinflammatory conditions. To further elucidate this, we investigated amyloid metabolism in patients with Lyme neuroborreliosis (LNB. Methods The first part of the study was a cross-sectional cohort study in 61 patients with acute facial palsy (19 with LNB and 42 with idiopathic facial paresis, Bell's palsy and 22 healthy controls. CSF was analysed for the β-amyloid peptides Aβ38, Aβ40 and Aβ42, and the amyloid precursor protein (APP isoforms α-sAPP and β-sAPP. CSF total-tau (T-tau, phosphorylated tau (P-tau and neurofilament protein (NFL were measured to monitor neural cell damage. The second part of the study was a prospective cohort-study in 26 LNB patients undergoing consecutive lumbar punctures before and after antibiotic treatment to study time-dependent dynamics of the biomarkers. Results In the cross-sectional study, LNB patients had lower levels of CSF α-sAPP, β-sAPP and P-tau, and higher levels of CSF NFL than healthy controls and patients with Bell's palsy. In the prospective study, LNB patients had low levels of CSF α-sAPP, β-sAPP and P-tau at baseline, which all increased towards normal at follow-up. Conclusions Amyloid metabolism is altered in LNB. CSF levels of α-sAPP, β-sAPP and P-tau are decreased in acute infection and increase after treatment. In combination with earlier findings in multiple sclerosis, cerebral SLE and HIV with cerebral engagement, this points to an influence of neuroinflammation on amyloid metabolism.

  17. Magnetic Fluids Have Ability to Decrease Amyloid Aggregation Associated with Amyloid-Related Diseases

    Science.gov (United States)

    Antosova, Andrea; Koneracka, Martina; Siposova, Katarina; Zavisova, Vlasta; Daxnerova, Zuzana; Vavra, Ivo; Fabian, Martin; Kopcansky, Peter; Gazova, Zuzana

    2010-12-01

    At least twenty human proteins can fold abnormally to form pathological deposits that are associated with several amyloid-related diseases. We have investigated the effect of four magnetic fluids (MFs)—electrostatically stabilized Fe3O4 magnetic nanoparticles (MF1) and sterically stabilized Fe3O4 magnetic nanoparticles by sodium oleate (MF2, MF3 and MF4) with adsorbed BSA (MF2) or dextran (MF4)—on amyloid aggregation of two proteins, human insulin and chicken egg lysozyme. The morphology, particle size and size distribution of the prepared magnetic fluids were characterized. We have found that MFs are able to decrease amyloid aggregation of both studied proteins and the extent of depolymerization depended on the MF properties. The most effective reduction was observed for MF4 as 90% decrease of amyloids was detected for insulin and lysozyme amyloid aggregates. Our findings indicate that MFs have potential to be used for treatment of amyloid diseases.

  18. S-sulfonation of transthyretin is an important trigger step in the formation of transthyretin-related amyloid fibril.

    Science.gov (United States)

    Nakanishi, Toyofumi; Yoshioka, Masanori; Moriuchi, Kazuyoshi; Yamamoto, Daisuke; Tsuji, Motomu; Takubo, Takayuki

    2010-07-01

    Senile systemic amyloidosis and familial amyloid polyneuropathy are caused by oxidative deposition of conformationally altered transthyretin (TTR). We identified oxidative modification of the 10th cysteine of TTR through S-sulfonation in vitro. Based on mass spectrometric analysis, we determined the spectrophotometric, western blotting, and fluorescent microscopic properties of TTR incubated with and without cysteine-S-sulfonate in acidic (pH 4) and alkaline (pH 8) conditions at 37 degrees. The absorption of the aggregated TTR molecules increased more with incubation time and the concentration of cysteine-S-sulfonate at pH 4 than at pH 8. The Congo red binding to the S-sulfonated TTR at pH 4 was saturated with an apparent Bmax of 2.01 mol per mole of the S-sulfonated TTR and apparent KD of 7.75x10(-6) M. On the other hand, the Bmax of cysteinyl TTR was 1.38, and its KD was 3.52x10(-6) M while the Bmax of reduced TTR was 0.86, and its KD was 2.86x10(-6) M. Moreover, we detected positive amyloid fibril staining using Thioflavin T and Congo red with the S-sulfonated TTR but not with untreated or reduced TTR by microscopic fluorescent analysis. After modification of TTR in vitro, oligomers resisted reduction and denaturation was irreversibly induced, and which contributed differences in the Western blotting patterns obtained with four anti-TTR antibodies. In conclusion, this study showed that the formation of S-sulfonation of TTR through oxidative modifications of the thiol residue on the 10th cysteine of TTR is an important trigger step in the formation of transthyretin-related amyloid fibril. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  19. Self-reported confusion is related to global and regional β-amyloid: data from the Women's healthy ageing project.

    Science.gov (United States)

    McCluskey, Georgia E; Yates, Paul; Villemagne, Victor L; Rowe, Christopher; Szoeke, Cassandra E I

    2018-02-01

    Disease-modifying treatments for Alzheimer's disease (AD) may require implementation during early stages of β-amyloid accumulation, well before patients have objective cognitive decline. In this study we aimed to assess the clinical value of subjective cognitive impairment (SCI) by examining the cross-sectional relationship between β-amyloid load and SCI. Cerebral β-amyloid and SCI was assessed in a cohort of 112 cognitively normal subjects. Subjective cognition was evaluated using specific questions on memory and cognition and the MAC-Q. Participants had cerebral β-amyloid load measured with 18 F-Florbetaben Positron Emission Tomography (PET). No associations were found between measures of subjective memory impairment and cerebral β-amyloid. However, by self-reported confusion was predictive of a higher global β-amyloid burden (p = 0.002), after controlling for confounders. Regional analysis revealed significant associations of confusion with β-amyloid in the prefrontal region (p = 0.004), posterior cingulate and precuneus cortices (p = 0.004) and the lateral temporal lobes (p = 0.001) after controlling for confounders. An in vivo biomarker for AD pathology was associated with SCI by self-reported confusion on cross-sectional analysis. Whilst there has been a large body of research on SMC, our results indicate more research is needed to explore symptoms of confusion.

  20. Vascular and amyloid pathologies are independent predictors of cognitive decline in normal elderly.

    Science.gov (United States)

    Vemuri, Prashanthi; Lesnick, Timothy G; Przybelski, Scott A; Knopman, David S; Preboske, Greg M; Kantarci, Kejal; Raman, Mekala R; Machulda, Mary M; Mielke, Michelle M; Lowe, Val J; Senjem, Matthew L; Gunter, Jeffrey L; Rocca, Walter A; Roberts, Rosebud O; Petersen, Ronald C; Jack, Clifford R

    2015-03-01

    Our primary objective was to investigate a biomarker driven model for the interrelationships between vascular disease pathology, amyloid pathology, and longitudinal cognitive decline in cognitively normal elderly subjects between 70 and 90 years of age. Our secondary objective was to investigate the beneficial effect of cognitive reserve on these interrelationships. We used brain amyloid-β load measured using Pittsburgh compound B positron emission tomography as a marker for amyloid pathology. White matter hyperintensities and brain infarcts were measured using fluid-attenuated inversion recovery magnetic resonance imaging as a marker for vascular pathology. We studied 393 cognitively normal elderly participants in the population-based Mayo Clinic Study of Aging who had a baseline 3 T fluid-attenuated inversion recovery magnetic resonance imaging assessment, Pittsburgh compound B positron emission tomography scan, baseline cognitive assessment, lifestyle measures, and at least one additional clinical follow-up. We classified subjects as being on the amyloid pathway if they had a global cortical amyloid-β load of ≥1.5 standard uptake value ratio and those on the vascular pathway if they had a brain infarct and/or white matter hyperintensities load ≥1.11% of total intracranial volume (which corresponds to the top 25% of white matter hyperintensities in an independent non-demented sample). We used a global cognitive z-score as a measure of cognition. We found no evidence that the presence or absence of vascular pathology influenced the presence or absence of amyloid pathology and vice versa, suggesting that the two processes seem to be independent. Baseline cognitive performance was lower in older individuals, in males, those with lower education/occupation, and those on the amyloid pathway. The rate of cognitive decline was higher in older individuals (P pathologies. In those subjects with both vascular and amyloid pathologies, the effect of both pathologies on

  1. Amyloid Imaging in Aging and Dementia: Testing the Amyloid Hypothesis In Vivo

    Directory of Open Access Journals (Sweden)

    G. D. Rabinovici

    2009-01-01

    Full Text Available Amyloid imaging represents a major advance in neuroscience, enabling the detection and quantification of pathologic protein aggregations in the brain. In this review we survey current amyloid imaging techniques, focusing on positron emission tomography (PET with ^{11}carbon-labelled Pittsburgh Compound-B (11C-PIB, the most extensively studied and best validated tracer. PIB binds specifically to fibrillar beta-amyloid (Aβ deposits, and is a sensitive marker for Aβ pathology in cognitively normal older individuals and patients with mild cognitive impairment (MCI and Alzheimer’s disease (AD. PIB-PET provides us with a powerful tool to examine in vivo the relationship between amyloid deposition, clinical symptoms, and structural and functional brain changes in the continuum between normal aging and AD. Amyloid imaging studies support a model in which amyloid deposition is an early event on the path to dementia, beginning insidiously in cognitively normal individuals, and accompanied by subtle cognitive decline and functional and structural brain changes suggestive of incipient AD. As patients progress to dementia, clinical decline and neurodegeneration accelerate and proceed independently of amyloid accumulation. In the future, amyloid imaging is likely to supplement clinical evaluation in selecting patients for anti-amyloid therapies, while MRI and FDG-PET may be more appropriate markers of clinical progression.

  2. Multimodal PET Imaging of Amyloid and Tau Pathology in Alzheimer Disease and Non-Alzheimer Disease Dementias.

    Science.gov (United States)

    Xia, Chenjie; Dickerson, Bradford C

    2017-07-01

    Biomarkers of the molecular pathology underpinning dementia syndromes are increasingly recognized as crucial for diagnosis and development of disease-modifying treatments. Amyloid PET imaging is an integral part of the diagnostic assessment of Alzheimer disease. Its use has also deepened understanding of the role of amyloid pathology in Lewy body disorders and aging. Tau PET imaging is an imaging biomarker that will likely play an important role in the diagnosis, monitoring, and treatment in dementias. Using tau PET imaging to examine how tau pathology relates to amyloid and other markers of neurodegeneration will serve to better understand the pathophysiologic cascade that leads to dementia. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Acute paretic syndrome in juvenile White Leghorn chickens resembles late stages of acute inflammatory demyelinating polyneuropathies in humans

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    Preisinger Rudolf

    2010-01-01

    Full Text Available Abstract Background Sudden limb paresis is a common problem in White Leghorn flocks, affecting about 1% of the chicken population before achievement of sexual maturity. Previously, a similar clinical syndrome has been reported as being caused by inflammatory demyelination of peripheral nerve fibres. Here, we investigated in detail the immunopathology of this paretic syndrome and its possible resemblance to human neuropathies. Methods Neurologically affected chickens and control animals from one single flock underwent clinical and neuropathological examination. Peripheral nervous system (PNS alterations were characterised using standard morphological techniques, including nerve fibre teasing and transmission electron microscopy. Infiltrating cells were phenotyped immunohistologically and quantified by flow cytometry. The cytokine expression pattern was assessed by quantitative real-time PCR (qRT-PCR. These investigations were accomplished by MHC genotyping and a PCR screen for Marek's disease virus (MDV. Results Spontaneous paresis of White Leghorns is caused by cell-mediated, inflammatory demyelination affecting multiple cranial and spinal nerves and nerve roots with a proximodistal tapering. Clinical manifestation coincides with the employment of humoral immune mechanisms, enrolling plasma cell recruitment, deposition of myelin-bound IgG and antibody-dependent macrophageal myelin-stripping. Disease development was significantly linked to a 539 bp microsatellite in MHC locus LEI0258. An aetiological role for MDV was excluded. Conclusions The paretic phase of avian inflammatory demyelinating polyradiculoneuritis immunobiologically resembles the late-acute disease stages of human acute inflammatory demyelinating polyneuropathy, and is characterised by a Th1-to-Th2 shift.

  4. Calumenin interacts with serum amyloid P component

    DEFF Research Database (Denmark)

    Vorum, H; Jacobsen, Christian; Honoré, Bent

    2000-01-01

    with calumenin in the presence of Ca(2+). Amino acid sequencing identified this protein as serum amyloid P component (SAP). Furthermore, we verified and characterized the calumenin-SAP interaction by the surface plasmon resonance technique. The findings indicate that calumenin may participate...... in the immunological defense system and could be involved in the pathological process of amyloidosis that leads to formation of amyloid deposits seen in different types of tissues. Udgivelsesdato: 2000-Jan-14...

  5. Natural product-based amyloid inhibitors.

    Science.gov (United States)

    Velander, Paul; Wu, Ling; Henderson, Frances; Zhang, Shijun; Bevan, David R; Xu, Bin

    2017-09-01

    Many chronic human diseases, including multiple neurodegenerative diseases, are associated with deleterious protein aggregates, also called protein amyloids. One common therapeutic strategy is to develop protein aggregation inhibitors that can slow down, prevent, or remodel toxic amyloids. Natural products are a major class of amyloid inhibitors, and several dozens of natural product-based amyloid inhibitors have been identified and characterized in recent years. These plant- or microorganism-extracted compounds have shown significant therapeutic potential from in vitro studies as well as in vivo animal tests. Despite the technical challenges of intrinsic disordered or partially unfolded amyloid proteins that are less amenable to characterizations by structural biology, a significant amount of research has been performed, yielding biochemical and pharmacological insights into how inhibitors function. This review aims to summarize recent progress in natural product-based amyloid inhibitors and to analyze their mechanisms of inhibition in vitro. Major classes of natural product inhibitors and how they were identified are described. Our analyses comprehensively address the molecular interactions between the inhibitors and relevant amyloidogenic proteins. These interactions are delineated at molecular and atomic levels, which include covalent, non-covalent, and metal-mediated mechanisms. In vivo animal studies and clinical trials have been summarized as an extension. To enhance natural product bioavailability in vivo, emerging work using nanocarriers for delivery has also been described. Finally, issues and challenges as well as future development of such inhibitors are envisioned. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Hybrid Amyloid Membranes for Continuous Flow Catalysis.

    Science.gov (United States)

    Bolisetty, Sreenath; Arcari, Mario; Adamcik, Jozef; Mezzenga, Raffaele

    2015-12-29

    Amyloid fibrils are promising nanomaterials for technological applications such as biosensors, tissue engineering, drug delivery, and optoelectronics. Here we show that amyloid-metal nanoparticle hybrids can be used both as efficient active materials for wet catalysis and as membranes for continuous flow catalysis applications. Initially, amyloid fibrils generated in vitro from the nontoxic β-lactoglobulin protein act as templates for the synthesis of gold and palladium metal nanoparticles from salt precursors. The resulting hybrids possess catalytic features as demonstrated by evaluating their activity in a model catalytic reaction in water, e.g., the reduction of 4-nitrophenol into 4-aminophenol, with the rate constant of the reduction increasing with the concentration of amyloid-nanoparticle hybrids. Importantly, the same nanoparticles adsorbed onto fibrils surface show improved catalytic efficiency compared to the same unattached particles, pointing at the important role played by the amyloid fibril templates. Then, filter membranes are prepared from the metal nanoparticle-decorated amyloid fibrils by vacuum filtration. The resulting membranes serve as efficient flow catalysis active materials, with a complete catalytic conversion achieved within a single flow passage of a feeding solution through the membrane.

  7. Islet Amyloid Polypeptide: Structure, Function, and Pathophysiology

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    Rehana Akter

    2016-01-01

    Full Text Available The hormone islet amyloid polypeptide (IAPP, or amylin plays a role in glucose homeostasis but aggregates to form islet amyloid in type-2 diabetes. Islet amyloid formation contributes to β-cell dysfunction and death in the disease and to the failure of islet transplants. Recent work suggests a role for IAPP aggregation in cardiovascular complications of type-2 diabetes and hints at a possible role in type-1 diabetes. The mechanisms of IAPP amyloid formation in vivo or in vitro are not understood and the mechanisms of IAPP induced β-cell death are not fully defined. Activation of the inflammasome, defects in autophagy, ER stress, generation of reactive oxygen species, membrane disruption, and receptor mediated mechanisms have all been proposed to play a role. Open questions in the field include the relative importance of the various mechanisms of β-cell death, the relevance of reductionist biophysical studies to the situation in vivo, the molecular mechanism of amyloid formation in vitro and in vivo, the factors which trigger amyloid formation in type-2 diabetes, the potential role of IAPP in type-1 diabetes, the development of clinically relevant inhibitors of islet amyloidosis toxicity, and the design of soluble, bioactive variants of IAPP for use as adjuncts to insulin therapy.

  8. Evaluation of diabetic polyneuropathy in Type 2 diabetes mellitus by nerve conduction study and association of severity of neuropathy with serum sFasL level

    Directory of Open Access Journals (Sweden)

    Avijit Mondal

    2012-01-01

    Full Text Available Introduction: Diabetes mellitus (DM, a growing health problem globally, has reached epidemic proportions in India. Recently, Fas-mediated apoptosis has been proposed as a causative factor responsible for neuronal degeneration in diabetic polyneuropathy (DPN, but there are very few studies to show association of serum soluble Fas ligand (sFasL level with severity of neuropathy. Aim and Objective: The aim of this study was to investigate whether serum sFasL, a transmembrane glycoprotein involved in apoptosis, has any association with severity of peripheral neuropathy in Type 2 DM. Materials and Methods: The study was conducted in Department of Physiology in collaboration with Department of Endocrinology, IPGME&R. sFasL levels in serum were assessed using ELISA method in healthy individuals (n = 16, newly diagnosed diabetic controls (n = 16 without any complications, and in DPN cases (n = 33 with predominant neuropathy only. All subjects underwent both electrodiagnostic procedures and vibration perception threshold (VPT for quantitative assessment of the severity of neuropathy. Using nerve conduction studies, amplitudes, velocities, and latencies of both sensory and motor nerves were recorded. Results: In DPN patients, concentration of sFasL levels (87.53 ± 3.49 was significantly decreased (P < 0.0001 not only when compared with normal controls (225.30 ± 2.97 but also when compared with diabetic patients without any complication (161 ± 3.63. Moreover, the concentration of sFasL is significantly (P < 0.0001 associated with the severity of neuropathy both by VPT and nerve conduction velocity (NCV. Conclusion: Fas-mediated apoptosis is involved in Type 2 DM and might be associated with the severity of polyneuropathy.

  9. Immunoprecipitation of amyloid fibrils by the use of an antibody that recognizes a generic epitope common to amyloid fibrils.

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    Erin R Greiner

    Full Text Available Amyloid fibrils are associated with many maladies, including Alzheimer's disease (AD. The isolation of amyloids from natural materials is very challenging because the extreme structural stability of amyloid fibrils makes it difficult to apply conventional protein science protocols to their purification. A protocol to isolate and detect amyloids is desired for the diagnosis of amyloid diseases and for the identification of new functional amyloids. Our aim was to develop a protocol to purify amyloid from organisms, based on the particular characteristics of the amyloid fold, such as its resistance to proteolysis and its capacity to be recognized by specific conformational antibodies. We used a two-step strategy with proteolytic digestion as the first step followed by immunoprecipitation using the amyloid conformational antibody LOC. We tested the efficacy of this method using as models amyloid fibrils produced in vitro, tissue extracts from C. elegans that overexpress Aβ peptide, and cerebrospinal fluid (CSF from patients diagnosed with AD. We were able to immunoprecipitate Aβ(1-40 amyloid fibrils, produced in vitro and then added to complex biological extracts, but not α-synuclein and gelsolin fibrils. This method was useful for isolating amyloid fibrils from tissue homogenates from a C. elegans AD model, especially from aged worms. Although we were able to capture picogram quantities of Aβ(1-40 amyloid fibrils produced in vitro when added to complex biological solutions, we could not detect any Aβ amyloid aggregates in CSF from AD patients. Our results show that although immunoprecipitation using the LOC antibody is useful for isolating Aβ(1-40 amyloid fibrils, it fails to capture fibrils of other amyloidogenic proteins, such as α-synuclein and gelsolin. Additional research might be needed to improve the affinity of these amyloid conformational antibodies for an array of amyloid fibrils without compromising their selectivity before

  10. Cognitive and functional patterns of nondemented subjects with equivocal visual amyloid PET findings

    International Nuclear Information System (INIS)

    Payoux, P.; Delrieu, J.; Gallini, A.; Cantet, C.; Voisin, T.; Gillette-Guyonnet, S.; Vellas, B.; Adel, D.; Salabert, A.S.; Hitzel, A.; Tafani, M.; Verbizier, D. de; Darcourt, J.; Fernandez, P.; Monteil, J.; Carrie, I.; Pontecorvo, M.; Andrieu, S.

    2015-01-01

    Despite good to excellent inter-reader agreement in the evaluation of amyloid load on PET scans in subjects with Alzheimer's disease, some equivocal findings have been reported in the literature. We aimed to describe the clinical characteristics of subjects with equivocal PET images. Nondemented subjects aged 70 years or more were enrolled from the MAPT trial. Cognitive and functional assessments were conducted at baseline, at 6 months, and annually for 3 years. During the follow-up period, 271 subjects had 18 F-AV45 PET scans. Images were visually assessed by three observers and classified as positive, negative or equivocal (if one observer disagreed). After debate, equivocal images were reclassified as positive (EP+) or negative (EP-). Scans were also classified by semiautomated quantitative analysis using mean amyloid uptake of cortical regions. We evaluated agreement among the observers, and between visual and quantitative assessments using kappa coefficients, and compared the clinical characteristics of the subjects according to their PET results. In 158 subjects (58.30 %) the PET scan was negative for amyloid, in 77 (28.41 %) the scan was positive and in 36 (13.28 %) the scan was equivocal. Agreement among the three observers was excellent (kappa 0.80). Subjects with equivocal images were more frequently men (58 % vs. 37 %) and exhibited intermediate scores on cognitive and functional scales between those of subjects with positive and negative scans. Amyloid load differed between the EP- and negative groups and between the EP+ and positive groups after reclassification. Equivocal amyloid PET images could represent a neuroimaging entity with intermediate amyloid load but without a specific neuropsychological pattern. Clinical follow-up to assess cognitive evolution in subjects with equivocal scans is needed. (orig.)

  11. Cognitive and functional patterns of nondemented subjects with equivocal visual amyloid PET findings

    Energy Technology Data Exchange (ETDEWEB)

    Payoux, P. [Purpan University Hospital, Department of Nuclear Medicine, CHU Toulouse, Toulouse (France); Inserm, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); INSERM U825, CHU Purpan, Toulouse Cedex (France); Delrieu, J. [Purpan University Hospital, Gerontopole, Department of Geriatrics, CHU Toulouse, Toulouse (France); INSERM UMR 1027, Toulouse (France); Gallini, A.; Cantet, C.; Voisin, T.; Gillette-Guyonnet, S.; Vellas, B. [Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Purpan University Hospital, Gerontopole, Department of Geriatrics, CHU Toulouse, Toulouse (France); INSERM UMR 1027, Toulouse (France); Adel, D.; Salabert, A.S. [Inserm, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Hitzel, A. [Purpan University Hospital, Department of Nuclear Medicine, CHU Toulouse, Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Tafani, M. [Purpan University Hospital, Department of Nuclear Medicine, CHU Toulouse, Toulouse (France); Inserm, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Verbizier, D. de [Montpellier University Hospital, Department of Nuclear Medicine, Montpellier (France); Darcourt, J. [Centre Antoine Lacassagne, Nuclear Medicine Department, Nice (France); University of Nice-Sophia Antipolis, Nice (France); Fernandez, P. [Pellegrin University Hospital Bordeaux, Nuclear Medicine Department, Bordeaux (France); University Bordeaux II, CNRS UMR 5287 - INCIA, Victor Segalen, Bordeaux (France); Monteil, J. [University Hospital, Department of Nuclear Medicine, Limoges (France); University of Limoges, Limoges (France); Carrie, I. [Purpan University Hospital, Gerontopole, Department of Geriatrics, CHU Toulouse, Toulouse (France); Pontecorvo, M. [Avid Radiopharmaceuticals, Philadelphia, PA (United States); Andrieu, S. [Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques, UMR 825, Toulouse (France); Purpan University Hospital, Gerontopole, Department of Geriatrics, CHU Toulouse, Toulouse (France); INSERM UMR 1027, Toulouse (France); CHU Toulouse, Department of Epidemiology and Public Health, Toulouse (France)

    2015-08-15

    Despite good to excellent inter-reader agreement in the evaluation of amyloid load on PET scans in subjects with Alzheimer's disease, some equivocal findings have been reported in the literature. We aimed to describe the clinical characteristics of subjects with equivocal PET images. Nondemented subjects aged 70 years or more were enrolled from the MAPT trial. Cognitive and functional assessments were conducted at baseline, at 6 months, and annually for 3 years. During the follow-up period, 271 subjects had {sup 18}F-AV45 PET scans. Images were visually assessed by three observers and classified as positive, negative or equivocal (if one observer disagreed). After debate, equivocal images were reclassified as positive (EP+) or negative (EP-). Scans were also classified by semiautomated quantitative analysis using mean amyloid uptake of cortical regions. We evaluated agreement among the observers, and between visual and quantitative assessments using kappa coefficients, and compared the clinical characteristics of the subjects according to their PET results. In 158 subjects (58.30 %) the PET scan was negative for amyloid, in 77 (28.41 %) the scan was positive and in 36 (13.28 %) the scan was equivocal. Agreement among the three observers was excellent (kappa 0.80). Subjects with equivocal images were more frequently men (58 % vs. 37 %) and exhibited intermediate scores on cognitive and functional scales between those of subjects with positive and negative scans. Amyloid load differed between the EP- and negative groups and between the EP+ and positive groups after reclassification. Equivocal amyloid PET images could represent a neuroimaging entity with intermediate amyloid load but without a specific neuropsychological pattern. Clinical follow-up to assess cognitive evolution in subjects with equivocal scans is needed. (orig.)

  12. Augmenting Amyloid PET Interpretations With Quantitative Information Improves Consistency of Early Amyloid Detection.

    Science.gov (United States)

    Harn, Nicholas R; Hunt, Suzanne L; Hill, Jacqueline; Vidoni, Eric; Perry, Mark; Burns, Jeffrey M

    2017-08-01

    Establishing reliable methods for interpreting elevated cerebral amyloid-β plaque on PET scans is increasingly important for radiologists, as availability of PET imaging in clinical practice increases. We examined a 3-step method to detect plaque in cognitively normal older adults, focusing on the additive value of quantitative information during the PET scan interpretation process. Fifty-five F-florbetapir PET scans were evaluated by 3 experienced raters. Scans were first visually interpreted as having "elevated" or "nonelevated" plaque burden ("Visual Read"). Images were then processed using a standardized quantitative analysis software (MIMneuro) to generate whole brain and region of interest SUV ratios. This "Quantitative Read" was considered elevated if at least 2 of 6 regions of interest had an SUV ratio of more than 1.1. The final interpretation combined both visual and quantitative data together ("VisQ Read"). Cohen kappa values were assessed as a measure of interpretation agreement. Plaque was elevated in 25.5% to 29.1% of the 165 total Visual Reads. Interrater agreement was strong (kappa = 0.73-0.82) and consistent with reported values. Quantitative Reads were elevated in 45.5% of participants. Final VisQ Reads changed from initial Visual Reads in 16 interpretations (9.7%), with most changing from "nonelevated" Visual Reads to "elevated." These changed interpretations demonstrated lower plaque quantification than those initially read as "elevated" that remained unchanged. Interrater variability improved for VisQ Reads with the addition of quantitative information (kappa = 0.88-0.96). Inclusion of quantitative information increases consistency of PET scan interpretations for early detection of cerebral amyloid-β plaque accumulation.

  13. Impact of etiology and duration of pain on pharmacological treatment effects in painful polyneuropathy

    DEFF Research Database (Denmark)

    Sindrup, Søren Hein; Holbech, J.; Demant, Dyveke T

    2017-01-01

    baseline registration of symptoms, signs and quantitative sensory testing. 244 patient records of drug effect distributed over treatments with three antidepressants (imipramine, venlafaxine, escitalopram) and two anticonvulsants (pregabalin, oxcarbazepine) were analysed. Results: Diabetes as etiology...... of polyneuropathy had no impact on the effect of antidepressants (imipramine, venlafaxine, escitalopram), but there was a significant interaction with treatment effect on anticonvulsants with better effects in diabetics (0.86 NRS points, p = 0.021) with most pronounced interaction for oxcarbazepine (1.47 NRS points...

  14. Exercise engagement as a moderator of APOE effects on amyloid deposition

    Science.gov (United States)

    Head, Denise; Bugg, Julie M.; Goate, Alison M.; Fagan, Anne M.; Mintun, Mark A.; Benzinger, Tammie; Holtzman, David M.; Morris, John C.

    2012-01-01

    Objective APOE ε4 status has been associated with greater cortical amyloid deposition whereas exercise has been associated with less in cognitively normal adults. The primary objective here was to examine whether physical exercise moderates the association between APOE genotype and amyloid deposition in cognitively normal adults. Method APOE genotyping and a questionnaire on physical exercise engagement over the last decade were obtained in conjunction with cerebrospinal fluid (CSF) samples and amyloid imaging with PET-PIB. Participants were classified as either low or high exercisers based on exercise guidelines of the American Heart Association. Subjects 201 cognitively normal adults (135 females) aged 45–88 were recruited from the Knight Alzheimer Disease Research Center at Washington University. CSF samples were collected from 165 participants. Amyloid imaging was performed on 163 participants. Results APOE ε4 carriers evidenced higher PIB binding (pexercise engagement for PIB binding (p=.008) such that a more sedentary lifestyle was significantly associated with higher PIB binding for ε4 carriers (p=.013) but not for ε4 non-carriers (p=.208). All findings remained significant after controlling for age, gender, education, hypertension, body mass index, diabetes, heart problems, history of depression and interval between assessments. Conclusion Collectively, these results suggest that cognitively normal sedentary APOE ε4+ individuals may be at augmented risk for cerebral amyloid deposition. PMID:22232206

  15. Computational Modelling of the Human Islet Amyloid Polypeptide

    DEFF Research Database (Denmark)

    Skeby, Katrine Kirkeby

    2014-01-01

    of a specific protein into amyloid fibrils. During this process, a cytotoxic event occurs which can be a serious actor in the evolvement of the disease. This thesis is concerned with elucidating the biological processes concerning amyloid proteins, more specifically, the peptide hormone human islet amyloid...... setup. We have exploited these strengths to study the interactions between an amyloid fibril and amyloid imaging agents. Imaging agents are promising tools for the detection of amyloid deposits in the brain of AD patients. This could aid in the early diagnosis as well as evaluation of new treatments......When proteins do not fold correctly, it can lead to very serious diseases. One such group of diseases is the amyloid diseases, of which Alzheimer’s disease (AD), Parkinson’s disease, and type 2 diabetes mellitus (T2DM) are members. The amyloid diseases are characterized by the aggregation...

  16. Interaction of magnetic nanoparticles with lysozyme amyloid fibrils

    International Nuclear Information System (INIS)

    Gdovinová, Veronika; Tomašovičová, Natália; Batko, Ivan; Batková, Marianna; Balejčíková, Lucia; Garamus, Vasyl M.; Petrenko, Viktor I.; Avdeev, Mikhail V.; Kopčanský, Peter

    2017-01-01

    This work is devoted to the structural study of complex solutions of magnetic nanoparticles with lysozyme amyloid fibrils due to possible ordering of such system by applying the external magnetic field. The interaction of magnetic nanoparticles with amyloid fibrils has been followed by atomic force microscopy and small-angle X-ray scattering. It has been observed that magnetic nanoparticles (MNPs) adsorb to lysozyme amyloid fibrils. It was found that MNPs alter amyloids structures, namely the diameter of lysozyme amyloid fibrils is increased whereas the length of fibrils is decreased. In the same time MNPs do not change the helical pitch significantly. - Highlights: • Solution of MNPs with lysozyme amyloid fibrils was characterized by AFM and SAXS. • MNPs adsorb to lysozyme amyloid fibrils. • Diameter and size of lysozyme amyloid fibrils change due to doping with MNPs.

  17. Interaction of magnetic nanoparticles with lysozyme amyloid fibrils

    Energy Technology Data Exchange (ETDEWEB)

    Gdovinová, Veronika [Institute of Experimental Physics SAS, Watsonova 47, 040 01 Košice (Slovakia); Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Tomašovičová, Natália, E-mail: nhudak@saske.sk [Institute of Experimental Physics SAS, Watsonova 47, 040 01 Košice (Slovakia); Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Batko, Ivan; Batková, Marianna; Balejčíková, Lucia [Institute of Experimental Physics SAS, Watsonova 47, 040 01 Košice (Slovakia); Garamus, Vasyl M. [Helmholtz-Zentrum Geesthacht: Zentrum fr Material, und Kstenforschung GmbH, Max-Plank-Strae 1, Geesthacht 216502 (Germany); Petrenko, Viktor I. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Physics Department, Taras Shevchenko Kyiv National University, Volodymyrska Street 64, 01601 Kyiv (Ukraine); Avdeev, Mikhail V. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, 141980 Dubna, Moscow Region (Russian Federation); Kopčanský, Peter [Institute of Experimental Physics SAS, Watsonova 47, 040 01 Košice (Slovakia)

    2017-06-01

    This work is devoted to the structural study of complex solutions of magnetic nanoparticles with lysozyme amyloid fibrils due to possible ordering of such system by applying the external magnetic field. The interaction of magnetic nanoparticles with amyloid fibrils has been followed by atomic force microscopy and small-angle X-ray scattering. It has been observed that magnetic nanoparticles (MNPs) adsorb to lysozyme amyloid fibrils. It was found that MNPs alter amyloids structures, namely the diameter of lysozyme amyloid fibrils is increased whereas the length of fibrils is decreased. In the same time MNPs do not change the helical pitch significantly. - Highlights: • Solution of MNPs with lysozyme amyloid fibrils was characterized by AFM and SAXS. • MNPs adsorb to lysozyme amyloid fibrils. • Diameter and size of lysozyme amyloid fibrils change due to doping with MNPs.

  18. Amyloid formation via supramolecular peptide assemblies.

    Science.gov (United States)

    Moore, Roger A; Hayes, Stanley F; Fischer, Elizabeth R; Priola, Suzette A

    2007-06-19

    Amyloid fibrils have been classically defined as linear, nonbranched polymeric proteins with a cross beta-sheet structure and the ability to alter the optical properties of the amyloid-specific dye Congo Red. Mounting evidence suggests that soluble oligomeric peptide assemblies approximately 2-20 nm in diameter are critical intermediates in amyloid formation. Using a pathogenic prion protein peptide comprised of residues 23-144, we demonstrate that, under quiescent but not agitated conditions, much larger globular assemblies up to 1 mum in diameter are made. These globules precede fibril formation and directly interact with growing fibril bundles. Fibrils made via these large spherical peptide assemblies displayed a remarkable diversity of ultrastructural features. Fibrillization of the Abeta1-40 peptide under similar conditions yielded similar results, suggesting a mechanism of general amyloid formation that can proceed through intermediates much larger than those previously described. Our data suggest that simply changing the physical microenvironment can profoundly influence the mechanism of amyloid formation and yield fibrils with novel ultrastructural properties.

  19. Halogenation dictates the architecture of amyloid peptide nanostructures.

    Science.gov (United States)

    Pizzi, Andrea; Pigliacelli, Claudia; Gori, Alessandro; Nonappa; Ikkala, Olli; Demitri, Nicola; Terraneo, Giancarlo; Castelletto, Valeria; Hamley, Ian W; Baldelli Bombelli, Francesca; Metrangolo, Pierangelo

    2017-07-20

    Amyloid peptides yield a plethora of interesting nanostructures though difficult to control. Here we report that depending on the number, position, and nature of the halogen atoms introduced into either one or both phenylalanine benzene rings of the amyloid β peptide-derived core-sequence KLVFF, four different architectures were obtained in a controlled manner. Our findings demonstrate that halogenation may develop as a general strategy to engineer amyloidal peptide self-assembly and obtain new amyloidal nanostructures.

  20. Orientation of aromatic residues in amyloid cores: Structural insights into prion fiber diversity

    KAUST Repository

    Reymer, Anna

    2014-11-17

    Structural conversion of one given protein sequence into different amyloid states, resulting in distinct phenotypes, is one of the most intriguing phenomena of protein biology. Despite great efforts the structural origin of prion diversity remains elusive, mainly because amyloids are insoluble yet noncrystalline and therefore not easily amenable to traditional structural-biology methods. We investigate two different phenotypic prion strains, weak and strong, of yeast translation termination factor Sup35 with respect to angular orientation of tyrosines using polarized light spectroscopy. By applying a combination of alignment methods the degree of fiber orientation can be assessed, which allows a relatively accurate determination of the aromatic ring angles. Surprisingly, the strains show identical average orientations of the tyrosines, which are evenly spread through the amyloid core. Small variations between the two strains are related to the local environment of a fraction of tyrosines outside the core, potentially reflecting differences in fibril packing.

  1. The pattern of amyloid accumulation in the brains of adults with Down syndrome

    Science.gov (United States)

    Annus, Tiina; Wilson, Liam R.; Hong, Young T.; Acosta–Cabronero, Julio; Fryer, Tim D.; Cardenas–Blanco, Arturo; Smith, Robert; Boros, Istvan; Coles, Jonathan P.; Aigbirhio, Franklin I.; Menon, David K.; Zaman, Shahid H.; Nestor, Peter J.; Holland, Anthony J.

    2016-01-01

    Introduction Adults with Down syndrome (DS) invariably develop Alzheimer's disease (AD) neuropathology. Understanding amyloid deposition in DS can yield crucial information about disease pathogenesis. Methods Forty-nine adults with DS aged 25–65 underwent positron emission tomography with Pittsburgh compound–B (PIB). Regional PIB binding was assessed with respect to age, clinical, and cognitive status. Results Abnormal PIB binding became evident from 39 years, first in striatum followed by rostral prefrontal-cingulo-parietal regions, then caudal frontal, rostral temporal, primary sensorimotor and occipital, and finally parahippocampal cortex, thalamus, and amygdala. PIB binding was related to age, diagnostic status, and cognitive function. Discussion PIB binding in DS, first appearing in striatum, began around age 40 and was strongly associated with dementia and cognitive decline. The absence of a substantial time lag between amyloid accumulation and cognitive decline contrasts to sporadic/familial AD and suggests this population's suitability for an amyloid primary prevention trial. PMID:26362596

  2. AL amyloid imaging and therapy with a monoclonal antibody to a cryptic epitope on amyloid fibrils.

    Directory of Open Access Journals (Sweden)

    Jonathan S Wall

    Full Text Available The monoclonal antibody 2A4 binds an epitope derived from a cleavage site of serum amyloid protein A (sAA containing a -Glu-Asp- amino acid pairing. In addition to its reactivity with sAA amyloid deposits, the antibody was also found to bind amyloid fibrils composed of immunoglobulin light chains. The antibody binds to synthetic fibrils and human light chain (AL amyloid extracts with high affinity even in the presence of soluble light chain proteins. Immunohistochemistry with biotinylated 2A4 demonstrated positive reaction with ALκ and ALλ human amyloid deposits in various organs. Surface plasmon resonance analyses using synthetic AL fibrils as a substrate revealed that 2A4 bound with a K(D of ∼10 nM. Binding was inhibited in the presence of the -Glu-Asp- containing immunogen peptide. Radiolabeled 2A4 specifically localized with human AL amyloid extracts implanted in mice (amyloidomas as evidenced by single photon emission (SPECT imaging. Furthermore, co-localization of the radiolabeled mAb with amyloid was shown in biodistribution and micro-autoradiography studies. Treatment with 2A4 expedited regression of ALκ amyloidomas in mice, likely mediated by the action of macrophages and neutrophils, relative to animals that received a control antibody. These data indicate that the 2A4 mAb might be of interest for potential imaging and immunotherapy in patients with AL amyloidosis.

  3. Long-Term Spinal Cord Stimulation Alleviates Mechanical Hypersensitivity and Increases Peripheral Cutaneous Blood Perfusion in Experimental Painful Diabetic Polyneuropathy.

    Science.gov (United States)

    van Beek, Maarten; Hermes, Denise; Honig, Wiel M; Linderoth, Bengt; van Kuijk, Sander M J; van Kleef, Maarten; Joosten, Elbert A

    2018-03-09

    This study utilizes a model of long-term spinal cord stimulation (SCS) in experimental painful diabetic polyneuropathy (PDPN) to investigate the behavioral response during and after four weeks of SCS (12 hours/day). Second, we investigated the effect of long-term SCS on peripheral cutaneous blood perfusion in experimental PDPN. Mechanical sensitivity was assessed in streptozotocin induced diabetic rats (n = 50) with von Frey analysis. Hypersensitive rats (n = 24) were implanted with an internal SCS battery, coupled to an SCS electrode covering spinal levels L2-L5. The effects of four weeks of daily conventional SCS for 12 hours (n = 12) or Sham SCS (n = 12) were evaluated with von Frey assessment, and laser Doppler imaging (LDI). Average paw withdrawal thresholds (PWT) increased during long-term SCS in the SCS group, in contrast to a decrease in the Sham group (Sham vs. SCS; p = 0.029). Twenty-four hours after long-term SCS average PWT remained higher in the SCS group. Furthermore, the SCS group showed a higher cutaneous blood perfusion during long-term SCS compared to the Sham group (Sham vs. SCS; p = 0.048). Forty-eight hours after long-term SCS, no differences in skin perfusion were observed. We demonstrated that long-term SCS results in decreased baseline mechanical hypersensitivity and results in increased peripheral blood perfusion during stimulation in a rat model of PDPN. Together, these findings indicate that long-term SCS results in modulation of the physiological circuitry related to the nociceptive system in addition to symptomatic treatment of painful symptoms. © 2018 The Authors. Neuromodulation: Technology at the Neural Interface published by Wiley Periodicals, Inc. on behalf of International Neuromodulation Society.

  4. The prion protein as a receptor for amyloid-beta

    NARCIS (Netherlands)

    Kessels, Helmut W.; Nguyen, Louis N.; Nabavi, Sadegh; Malinow, Roberto

    2010-01-01

    Increased levels of brain amyloid-beta, a secreted peptide cleavage product of amyloid precursor protein (APP), is believed to be critical in the aetiology of Alzheimer's disease. Increased amyloid-beta can cause synaptic depression, reduce the number of spine protrusions (that is, sites of synaptic

  5. Brazilin inhibits amyloid β-protein fibrillogenesis, remodels amyloid fibrils and reduces amyloid cytotoxicity

    Science.gov (United States)

    Du, Wen-Jie; Guo, Jing-Jing; Gao, Ming-Tao; Hu, Sheng-Quan; Dong, Xiao-Yan; Han, Yi-Fan; Liu, Fu-Feng; Jiang, Shaoyi; Sun, Yan

    2015-01-01

    Soluble amyloid β-protein (Aβ) oligomers, the main neurotoxic species, are predominantly formed from monomers through a fibril-catalyzed secondary nucleation. Herein, we virtually screened an in-house library of natural compounds and discovered brazilin as a dual functional compound in both Aβ42 fibrillogenesis inhibition and mature fibril remodeling, leading to significant reduction in Aβ42 cytotoxicity. The potent inhibitory effect of brazilin was proven by an IC50 of 1.5 +/- 0.3 μM, which was smaller than that of (-)-epigallocatechin gallate in Phase III clinical trials and about one order of magnitude smaller than those of curcumin and resveratrol. Most importantly, it was found that brazilin redirected Aβ42 monomers and its mature fibrils into unstructured Aβ aggregates with some β-sheet structures, which could prevent both the primary nucleation and the fibril-catalyzed secondary nucleation. Molecular simulations demonstrated that brazilin inhibited Aβ42 fibrillogenesis by directly binding to Aβ42 species via hydrophobic interactions and hydrogen bonding and remodeled mature fibrils by disrupting the intermolecular salt bridge Asp23-Lys28 via hydrogen bonding. Both experimental and computational studies revealed a different working mechanism of brazilin from that of known inhibitors. These findings indicate that brazilin is of great potential as a neuroprotective and therapeutic agent for Alzheimer's disease.

  6. [Proteomic technologies for identification of serum potential biomarkers of autoimmune demyelinating polyneuropathies].

    Science.gov (United States)

    Ziganshin, R Kh; Arapidi, G P; Azarkin, I V; Balmasova, I P; Timchenko, O L; Fed'kina, Iu A; Morozova, E A; Piradov, M A; Suponeva, N A; Iushchuk, N D; Govorun, V M

    2011-01-01

    Time-of-flight MALDI mass spectrometry (MALDI-TOF-MS) profiling of blood serum of patients with Guillain-Barré syndrome (GBS, 36 samples), chronic inflammatory demyelinating polyneuropathy (CIDP, 24 samples) and practically healthy donors (HD) (35 samples) was carried out in order to identify potential biomarkers of autoimmune demyelinating polyneuropathies (ADP). To simplify the peptide-protein mixture of serum prior to MALDI-TOF-MS analysis samples were pre-fractionated on magnetic microparticles with a weak cation-exchange (MB-WCX) surface. Comparative analysis of mass spectrometric data using the classification algorithms (genetic and neural network-controlled) revealed a characteristic set of peaks, agreed change area with a high specificity and sensitivity of the differentiated mass spectrometry profiles of the blood serum of patients with DPNP and healthy donors (for GBS values of these characteristics reached 100 and 100, and for CIDP 94.1 and 100% respectively). Comparative analysis of mass spectrometric profiles of serum samples obtained from patients with GBS and CIDP, allowed to build a classification model to differentiate these diseases from each other, with a specificity of 88.9 and a sensitivity of 80%.

  7. Development of Spontaneous Autoimmune Peripheral Polyneuropathy in B7-2–Deficient Nod Mice

    Science.gov (United States)

    Salomon, Benoît; Rhee, Lesley; Bour-Jordan, Helene; Hsin, Honor; Montag, Anthony; Soliven, Betty; Arcella, Jennifer; Girvin, Ann M.; Miller, Stephen D.; Bluestone, Jeffrey A.

    2001-01-01

    An increasing number of studies have documented the central role of T cell costimulation in autoimmunity. Here we show that the autoimmune diabetes-prone nonobese diabetic (NOD) mouse strain, deficient in B7-2 costimulation, is protected from diabetes but develops a spontaneous autoimmune peripheral polyneuropathy. All the female and one third of the male mice exhibited limb paralysis with histologic and electrophysiologic evidence of severe demyelination in the peripheral nerves beginning at 20 wk of age. No central nervous system lesions were apparent. The peripheral nerve tissue was infiltrated with dendritic cells, CD4+, and CD8+ T cells. Finally, CD4+ T cells isolated from affected animals induced the disease in NOD.SCID mice. Thus, the B7-2–deficient NOD mouse constitutes the first model of a spontaneous autoimmune disease of the peripheral nervous system, which has many similarities to the human disease, chronic inflammatory demyelinating polyneuropathy (CIDP). This model demonstrates that NOD mice have “cryptic” autoimmune defects that can polarize toward the nervous tissue after the selective disruption of CD28/B7-2 costimulatory pathway. PMID:11535635

  8. Tramadol relieves pain and allodynia in polyneuropathy: a randomised, double-blind, controlled trial.

    Science.gov (United States)

    Sindrup, S H; Andersen, G; Madsen, C; Smith, T; Brøsen, K; Jensen, T S

    1999-10-01

    It is generally believed that opioids relieve neuropathic pain less effectively than nociceptive pain and that they have no effect on some of the key characteristics of neuropathic pain such as touch-evoked pain (allodynia). Tramadol is an analgesic drug acting directly on opioid receptors and indirectly on monoaminergic receptor systems. The aim of this trial was to determine whether tramadol relieved painful polyneuropathy and reduced allodynia. The study design was randomised, double-blind, placebo-controlled and cross-over. After baseline observations, 45 patients were assigned to one of the two treatment sequences. The dose of tramadol slow-release tablets was titrated to at least 200 mg/day and at highest 400 mg/day. During the two treatment periods of 4 weeks duration, patients rated pain, paraesthesia and touch-evoked pain by use of 0-10 point numeric rating scales. Mechanical allodynia induced by stimulation with an electronic toothbrush was rated at the end of each treatment period with a similar scale. Thirty-four patients completed the study. Their ratings for pain (median 4 vs. 6, P=0.001), paraesthesia (4 vs. 6, P=0.001) and touch-evoked pain (3 vs. 5, P/=50% pain relief was 4.3 (95% confidence interval 2.4-20). It is concluded that tramadol appears to relieve both ongoing pain symptoms and the key neuropathic pain feature allodynia in polyneuropathy.

  9. Acute Inflammatory Demyelinating Polyneuropathy and a Unilateral Babinski/Plantar Reflex

    Directory of Open Access Journals (Sweden)

    Davide Cattano

    2008-01-01

    Full Text Available Acquired acute demyelinating peripheral polyneuropathy (AADP is a general classification of pathologies that could affect secondary the peripheral nervous system. They are characterized by an autoimmune process directed towards myelin. Clinically they are characterized by progressive weakness and mild sensory changes. Acute inflammatory demyelinating polyneuropathy often is referred to as Guillain-Barré syndrome (GBS. GBS is the major cause of acute nontraumatic paralysis in healthy people and it is caused by autoimmune response to viral agents (influenza, coxsackie, Epstein-Barr virus, or cytomegalovirus or bacterial infective organisms (Campylobacter jejuni, Mycoplasma pneumoniae. A detailed history, with symptoms of progressive usually bilateral weakness, hyporeflexia, with a typical demyelinating EMG pattern supports the diagnosis. Progressive affection of respiratory muscles and autonomic instability coupled with a protracted and unpredictable recovery normally results in the need for ICU management. We present a case report of a patient with a typical GBS presentation but with a unilateral upgoing plantar reflex (Babinski sign. A unifying diagnosis was made and based on a literature search in Pubmed appears to be the first described case of its kind.

  10. Fibrillar dimer formation of islet amyloid polypeptides

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Chi-cheng [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); de Pablo, Juan J. [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-05-08

    Amyloid deposits of human islet amyloid polypeptide (hIAPP), a 37-residue hormone co-produced with insulin, have been implicated in the development of type 2 diabetes. Residues 20 – 29 of hIAPP have been proposed to constitute the amyloidogenic core for the aggregation process, yet the segment is mostly unstructured in the mature fibril, according to solid-state NMR data. Here we use molecular simulations combined with bias-exchange metadynamics to characterize the conformational free energies of hIAPP fibrillar dimer and its derivative, pramlintide. We show that residues 20 – 29 are involved in an intermediate that exhibits transient β-sheets, consistent with recent experimental and simulation results. By comparing the aggregation of hIAPP and pramlintide, we illustrate the effects of proline residues on inhibition of the dimerization of IAPP. The mechanistic insights presented here could be useful for development of therapeutic inhibitors of hIAPP amyloid formation.

  11. Cerebral hemorrhage caused by amyloid angiopathy

    International Nuclear Information System (INIS)

    Hanyu, Haruo; Tomonaga, Masanori; Yoshimura, Masahiro; Yamanouchi, Hiroshi; Shimada, Hiroyuki.

    1985-01-01

    Cerebral hemorrhage caused by amyloid angiopathy was studied clinicopathologically, with special attention given to the CT images. Cerebral hemorrhage caused by amyloid angiopathy is characterized, by a lobar-type hemorrhage involving the cortex, with direct extension into the subarachnoid space. Multiple hemorrhages are frequent, and cortical infarctions are present as complications in elderly patients without risk factors. CT scans taken in 5 cases demonstrated lobar hemorrhages in superficial locations, frequently in multiple sites or recurrently, with surrounding edema and mass effect. A subarachnoid extension of the hemorrhage through the superficial cortex, proven pathologically in all cases, was noted by CT in 4 of the 5 cases. However, cortical infarction was not detected by CT in any case. Therefore, CT is of value in the diagnosis of cerebral hemorrhage due to amyloid angiopathy based on distinctive findings such as a lobar hemorrhage in superficial regions, with extension into the subarachnoid space, frequently in multiple sites or recurrently. (author)

  12. Fibrillar dimer formation of islet amyloid polypeptides

    Science.gov (United States)

    Chiu, Chi-cheng; de Pablo, Juan J.

    2015-09-01

    Amyloid deposits of human islet amyloid polypeptide (hIAPP), a 37-residue hormone co-produced with insulin, have been implicated in the development of type 2 diabetes. Residues 20 - 29 of hIAPP have been proposed to constitute the amyloidogenic core for the aggregation process, yet the segment is mostly unstructured in the mature fibril, according to solid-state NMR data. Here we use molecular simulations combined with bias-exchange metadynamics to characterize the conformational free energies of hIAPP fibrillar dimer and its derivative, pramlintide. We show that residues 20 - 29 are involved in an intermediate that exhibits transient β-sheets, consistent with recent experimental and simulation results. By comparing the aggregation of hIAPP and pramlintide, we illustrate the effects of proline residues on inhibition of the dimerization of IAPP. The mechanistic insights presented here could be useful for development of therapeutic inhibitors of hIAPP amyloid formation.

  13. Antimicrobial activity of human islet amyloid polypeptides: an insight into amyloid peptides' connection with antimicrobial peptides.

    Science.gov (United States)

    Wang, Lan; Liu, Qian; Chen, Jin-Chun; Cui, Yi-Xian; Zhou, Bing; Chen, Yong-Xiang; Zhao, Yu-Fen; Li, Yan-Mei

    2012-07-01

    Human islet amyloid polypeptide (hIAPP) shows an antimicrobial activity towards two types of clinically relevant bacteria. The potency of hIAPP varies with its aggregation states. Circular dichroism was employed to determine the interaction between hIAPP and bacteria lipid membrane mimic. The antimicrobial activity of each aggregate species is associated with their ability to induce membrane disruption. Our findings provide new evidence revealing the antimicrobial activity of amyloid peptide, which suggest a possible connection between amyloid peptides and antimicrobial peptides.

  14. Diagnostic performance of I-123-labeled serum amyloid P component scintigraphy in patients with amyloidosis

    NARCIS (Netherlands)

    Hazenberg, BPC; van Rijswijk, MH; Piers, DA; Lub-de Hooge, MN; Vellenga, E; Haagsma, EB; Hawkins, PN; Jager, PL

    Purpose: To assess the diagnostic accuracy and additional information provided by I-123-labeled serum amyloid P component ( SAP) scintigraphy in patients with systemic and localized amyloidosis. Subjects and Methods: I-123-labeled human SAP was injected intravenously into 20 controls and 189

  15. Diagnostic performance of amyloid A protein quantification in fat tissue of patients with clinical AA amyloidosis

    NARCIS (Netherlands)

    Hazenberg, Bouke P. C.; Bijzet, Johannes; Limburg, Pieter C.; Skinner, Martha; Hawkins, Philip N.; Butrimiene, Irena; Livneh, Avi; Lesnyak, Olga; Nasonov, Evgeney L.; Filipowicz-Sosnowska, Anna; Guel, Ahmet; Merlini, Giampaolo; Wiland, Piotr; Oezdogan, Huri; Gorevic, Peter D.; Ben Maiz, Hedi; Benson, Merrill D.; Direskeneli, Haner; Kaarela, Kalevi; Garceau, Denis; Hauck, Wendy; van Rijswijk, Martin

    Objective. Amyloid A protein quantification in fat tissue is a new immunochemical method for detecting AA amyloidosis, a rare but serious disease. The objective was to assess diagnostic performance in clinical AA amyloidosis. Methods. Abdominal subcutaneous fat tissue of patients with AA amyloidosis

  16. Case report 480: Periosteal amyloid tumor

    International Nuclear Information System (INIS)

    Yoshida, S.O.; Karjoo, R.; Johnstone, M.R.

    1988-01-01

    In summary, a 66-year-old woman presented with an asymptomatic left pretibial tumor of 7 years duration. Serial radiographs over this period demonstrated a slowly enlarging periosteal tumor with focal and increasing calcifications/ossifications. No involvement of the underlying medullary bone, as demonstrated by computed tomography was noted. Following the diagnosis by biopsy of an amyloid tumor, serum and urine electrophoreses, complete blood count, SMAC panel, erythrocyte sedimentation rate, and serum rheumatoid factor level were found to be within reference ranges. A needle biopsy of the abdominal wall failed to reveal amyloid in the fat by Congo-red staining. (orig.)

  17. A subset of fibromyalgia patients have findings suggestive of chronic inflammatory demyelinating polyneuropathy and appear to respond to IVIg.

    Science.gov (United States)

    Caro, X J; Winter, E F; Dumas, A J

    2008-02-01

    The aetiopathogenesis of the fibromyalgia syndrome (FMS) remains unknown. Recent reports, however, suggest that a subgroup of FMS subjects has an immune-mediated disease. Therefore, our primary objective was to study FMS subjects for evidence of an immune-mediated demyelinating polyneuropathy. Our secondary objective was to determine the effects of treating these FMS subjects with the immune modulator, intravenous immunoglobulin (IVIg). Fifty-eight FMS subjects, 26 rheumatic non-FMS subjects and 52 non-rheumatic non-FMS subjects were studied. Subjective measures of paraesthesias, weakness, stocking hypaesthesia, pain, fatigue and stiffness were made. Objective measures of tenderness, proximal muscle strength and electrodiagnostic (EDX) evidence of polyneuropathy and demyelination were also made. Eleven other FMS subjects underwent sural nerve biopsy. Paraesthesias, subjective weakness and stocking hypaesthesia were more common in FMS than in rheumatic non-FMS (P < or = 0.0001). Proximal muscle strength was less in FMS than in rheumatic non-FMS (P < or = 0.0001). EDX demonstrated a distal demyelinating polyneuropathy, suggestive of chronic inflammatory demyelinating polyneuropathy (CIDP), in 33% of FMS subjects. No rheumatic non-FMS subject had polyneuropathy (P = 0.005), or demyelination (P = 0.05). Fifteen FMS/CIDP subjects were subsequently treated with IVIg (400 mg/kg each day for 5 days). Pain (P = 0.01), tenderness (P = 0.001) and strength (P = 0.04) improved significantly. Fatigue and stiffness trended towards improvement. A significant subset of FMS subjects have clinical and EDX findings suggestive of CIDP. IVIg treatment shows promise in treating this subset. These observations have implications for better understanding and treating some FMS patients.

  18. Designed amyloid fibers as materials for selective carbon dioxide capture.

    Science.gov (United States)

    Li, Dan; Furukawa, Hiroyasu; Deng, Hexiang; Liu, Cong; Yaghi, Omar M; Eisenberg, David S

    2014-01-07

    New materials capable of binding carbon dioxide are essential for addressing climate change. Here, we demonstrate that amyloids, self-assembling protein fibers, are effective for selective carbon dioxide capture. Solid-state NMR proves that amyloid fibers containing alkylamine groups reversibly bind carbon dioxide via carbamate formation. Thermodynamic and kinetic capture-and-release tests show the carbamate formation rate is fast enough to capture carbon dioxide by dynamic separation, undiminished by the presence of water, in both a natural amyloid and designed amyloids having increased carbon dioxide capacity. Heating to 100 °C regenerates the material. These results demonstrate the potential of amyloid fibers for environmental carbon dioxide capture.

  19. Amyloid in basal cell carcinoma and seborrheic keratosis

    DEFF Research Database (Denmark)

    Olsen, K E; Westermark, Per

    1994-01-01

    The frequency of amyloid substance was studied in two different types of skin tumours: basal cell carcinoma and seborrheic keratosis. In 9 out of 49 cases of seborrheic keratosis amyloid substance was found. In the basal cell carcinomas, 194 out of 260 cases showed amyloid deposits, a rate...... that is higher than that previously reported. The basal cell carcinoma material was further studied regarding the amount of amyloid, mitotic rate, degree of apoptosis and the age of the patients. There was no correlation between the amount of amyloid and the mitotic rate, or the degree of apoptosis...

  20. Amyloid beta 1-42 and phoshorylated tau threonin 231 in brains of aged cynomolgus monkeys (Macaca fascicularis

    Directory of Open Access Journals (Sweden)

    Huda Shalahudin Darusman

    2014-11-01

    Full Text Available Pathological hallmarks indicative of Alzheimer’s disease, which are the plaques of Amyloid Beta 1-42 and neurofibrillary tangles, were found in brain of aged cynomolgus monkey. The aim of the study was to investigate if aged monkeys exhibiting spatial memory impairment and levels of biomarkers indicative of Alzheimer’s disease, had brain lesions similar to human patients suffering from senile dementia. Generating immunohistochemistry technique to biomarkers of Amyloid beta 1-42 and the phosphorylated tau 231, our study assessed the amyloidopathy, such as indicative to the senile plaques and cerebral amyloid angiopathy, and the tauopathy, to possible neurofibrillary tangles. Six aged monkeys were selected based on their spatial memory performance and profile of biomarkers of Alzheimer’s disease, divided equally to affected aged subject - with Memory-affected and low amyloid level, and aged with higher performance in memory and amyloid, as the age-matched subjects. Using immunohistochemistry, plaques of Amyloid Beta 1-42 were observed in two out of three brains of aged subjects with memory impairment and biomarkers indicative of Alzheimer’s disease. The cerebral amyloid angiopathy was observed in both aged monkey groups, and unlike in the human, the amyloids were found to deposit in the small veins and capillaries. In one of the affected individuals, phosphorylated tau was positively stained intracellularly of the neurons, indicating a possibility of an early stage of the formation of tangles. These findings add to the body of evidence of the utility of the aged cynomolgus monkeys as a spontaneous model for Alzheimer-related disease.

  1. Protein misfolding, congophilia, oligomerization, and defective amyloid processing in preeclampsia.

    Science.gov (United States)

    Buhimschi, Irina A; Nayeri, Unzila A; Zhao, Guomao; Shook, Lydia L; Pensalfini, Anna; Funai, Edmund F; Bernstein, Ira M; Glabe, Charles G; Buhimschi, Catalin S

    2014-07-16

    Preeclampsia is a pregnancy-specific disorder of unknown etiology and a leading contributor to maternal and perinatal morbidity and mortality worldwide. Because there is no cure other than delivery, preeclampsia is the leading cause of iatrogenic preterm birth. We show that preeclampsia shares pathophysiologic features with recognized protein misfolding disorders. These features include urine congophilia (affinity for the amyloidophilic dye Congo red), affinity for conformational state-dependent antibodies, and dysregulation of prototype proteolytic enzymes involved in amyloid precursor protein (APP) processing. Assessment of global protein misfolding load in pregnancy based on urine congophilia (Congo red dot test) carries diagnostic and prognostic potential for preeclampsia. We used conformational state-dependent antibodies to demonstrate the presence of generic supramolecular assemblies (prefibrillar oligomers and annular protofibrils), which vary in quantitative and qualitative representation with preeclampsia severity. In the first attempt to characterize the preeclampsia misfoldome, we report that the urine congophilic material includes proteoforms of ceruloplasmin, immunoglobulin free light chains, SERPINA1, albumin, interferon-inducible protein 6-16, and Alzheimer's β-amyloid. The human placenta abundantly expresses APP along with prototype APP-processing enzymes, of which the α-secretase ADAM10, the β-secretases BACE1 and BACE2, and the γ-secretase presenilin-1 were all up-regulated in preeclampsia. The presence of β-amyloid aggregates in placentas of women with preeclampsia and fetal growth restriction further supports the notion that this condition should join the growing list of protein conformational disorders. If these aggregates play a pathophysiologic role, our findings may lead to treatment for preeclampsia. Copyright © 2014, American Association for the Advancement of Science.

  2. Amyloid- and FDG-PET imaging in amyotrophic lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Matias-Guiu, Jordi A.; Pytel, Vanesa; Galan, Lucia; Valles-Salgado, Maria; Guerrero, Antonio; Moreno-Ramos, Teresa; Matias-Guiu, Jorge [Hospital Clinico San Carlos, San Carlos Institute for Health Research (IdISSC), Universidad Complutense de Madrid, Department of Neurology, Madrid (Spain); Cabrera-Martin, Maria Nieves; Carreras, Jose Luis [Hospital Clinico San Carlos, San Carlos Institute for Health Research (IdISSC), Universidad Complutense de Madrid, Department of Nuclear Medicine, Madrid (Spain)

    2016-10-15

    We aimed to study brain metabolism and presence of beta-amyloid deposits using positron emission tomography (PET) in patients with amyotrophic lateral sclerosis (ALS). This prospective cross-sectional study included 18 patients with definite or probable ALS according to the revised El Escorial diagnostic criteria, and 24 healthy controls. Patients underwent neurological and neuropsychological assessments, PET with {sup 18}F-fluorodeoxyglucose (FDG), and amyloid-PET with {sup 18}F-florbetaben. Patients with ALS showed hypometabolism in the frontal area and hypermetabolism in the cerebellum compared to healthy controls. Four patients (22 %) displayed cognitive impairment and decreased metabolism in the frontal area extending bilaterally to the parietal regions, and increased metabolism in the posterior area of the cerebellum. In patients with no cognitive impairment, metabolism was lower in the left superior frontal gyrus and higher in the anterior and posterior lobes of the cerebellum. In the individual analysis, six patients (35 %) displayed more anterior involvement with hypometabolism affecting the superior frontal, medial, and inferior gyri; six patients (35 %) exhibited a more posterior pattern with hypometabolism in the precentral and postcentral gyri and in the superior and inferior parietal lobules; two patients (11 %) showed a mixed pattern; and three patients (17 %) showed no alterations in brain metabolism. Three (16 %) showed increased {sup 18}F-florbetaben uptake compared to controls. We have identified two main patterns of brain metabolism with an association to cognitive status. Only a subgroup of patients showed an increased uptake of the amyloid tracer. Our results suggest that ALS is heterogeneous from a clinical, metabolic, and molecular standpoint. (orig.)

  3. Protective Effects of Indian Spice Curcumin Against Amyloid Beta in Alzheimer’s Disease

    Science.gov (United States)

    Reddy, P. Hemachandra; Manczak, Maria; Yin, Xiangling; Grady, Mary Catherine; Mitchell, Andrew; Tonk, Sahil; Kuruva, Chandra Sekhar; Bhatti, Jasvinder Singh; Kandimalla, Ramesh; Vijayan, Murali; Kumar, Subodh; Wang, Rui; Adi Pradeepkiran, Jangampalli; Ogunmokun, Gilbert; Thamarai, Kavya; Quesada, Kandi; Boles, Annette; Reddy, Arubala P

    2018-01-01

    The purpose of our article is to assess the current understanding of Indian spice ‘Curcumin’ against amyloid-β (Aβ)-induced toxicity in Alzheimer’s disease (AD) pathogenesis. Natural products, such as ginger, curcumin and gingko biloba have been used as diets and dietary supplements to treat human diseases, including cancer, cardiovascular, respiratory, infectious, diabetes, obesity, metabolic syndromes and neurological disorders. Products derived from plants are known to have protective effects, including anti-inflammatory, anti-oxidant, anti-arthritis, pro-healing and boosting memory cognitive functions. In the last decade, several groups have designed and synthesized curcumin and its derivatives and extensively tested using cell and mouse models of AD. Recent research on amyloid-β and curcumin has revealed that curcumin prevents amyloid-β aggregation and crosses the blood brain barrier (BBB), reach brain cells and protect neurons from various toxic insults of aging and amyloid-β in humans. Recent research has also reported that curcumin ameliorates cognitive decline and improves synaptic functions in mouse models of AD. Further, recent groups have initiated studies on elderly individuals and patients with AD and the outcome of these studies is currently being assessed. This article highlights the beneficial effects of curcumin on AD. This article also critically assesses the current limitations of curcumin’s bioavailability and urgent need for new formulation to increase its brain levels to treat patients with AD. PMID:29332042

  4. Radiologically Isolated Cerebral Amyloid Angiopathy-Related Inflammation.

    Science.gov (United States)

    Renard, Dimitri; Wacongne, Anne; Thouvenot, Eric

    2017-11-01

    In amyloid β-related angiitis of the central nervous system (also called cerebral amyloid angiopathy-related inflammation), cerebral amyloid angiopathy occurs in association with primary vasculitis of small- and medium-sized leptomeningeal and cortical arteries. To avoid brain biopsy, clinicoradiological criteria (including clinical features due to inflammation-related uni/multifocal white matter hyperintensities) for the diagnosis of cerebral amyloid angiopathy-related inflammation have been validated recently. We report 3 cases with acute symptoms directly related to cerebral amyloid angiopathy in the presence of asymptomatic cerebral amyloid angiopathy-related inflammation hyperintensities on initial magnetic resonance imaging. Recognizing radiological features of cerebral amyloid angiopathy-related inflammation in patients with cerebral amyloid angiopathy is important because radiological isolated cerebral amyloid angiopathy-related inflammation may become symptomatic and immunosuppressive treatment is often effective in cerebral amyloid angiopathy-related inflammation, although optimal treatment regimen is yet unknown. In contrast, apart from hypertension treatment, few therapeutic options exist in cerebral amyloid angiopathy. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  5. Nonpathological extracellular amyloid is present during normal epididymal sperm maturation.

    Directory of Open Access Journals (Sweden)

    Sandra Whelly

    Full Text Available Amyloids are aggregated proteins characterized by a specific cross-β-sheet structure and are typically associated with neurodegenerative diseases including Alzheimer's disease. Recently, however, several nonpathological amyloids have been found in intracellular organelles of normal mammalian tissues suggesting that amyloid may also carry out biological functions. We previously have shown that the epididymal cystatin CRES (cystatin-related epididymal spermatogenic, cst8, a reproductive-specific member of the cystatin superfamily of cysteine protease inhibitors, forms amyloid in vitro suggesting that CRES amyloid may also form in vivo within the epididymal lumen. Here we show that amyloid structures containing CRES are a component of the normal mouse epididymal lumen without any apparent cytotoxic effects on spermatozoa and that these structures change along the length of the tubule. These studies suggest the presence of a functional amyloid structure that may carry out roles in sperm maturation or maintenance of the luminal milieu and which itself may undergo maturational changes along the epididymis. In contrast to previous examples of functional amyloid which were intracellular, our studies now show that nonpathological/functional amyloid can also be extracellular. The presence of an extracellular and nonpathological amyloid in the epididymis suggests that similar amyloid structures may be present in other organ systems and may carry out distinctive tissue-specific functions.

  6. Stabilization of a β-hairpin in monomeric Alzheimer's amyloid-β peptide inhibits amyloid formation

    OpenAIRE

    Hoyer, Wolfgang; Grönwall, Caroline; Jonsson, Andreas; Ståhl, Stefan; Härd, Torleif

    2008-01-01

    According to the amyloid hypothesis, the pathogenesis of Alzheimer's disease is triggered by the oligomerization and aggregation of the amyloid-β (Aβ) peptide into protein plaques. Formation of the potentially toxic oligomeric and fibrillar Aβ assemblies is accompanied by a conformational change toward a high content of β-structure. Here, we report the solution structure of Aβ(1–40) in complex with the phage-display selected affibody protein ZAβ3, a binding protein of nanomolar affinity. Boun...

  7. Genetic Dissection of the Amyloid Precursor Protein in Developmental Function and Amyloid Pathogenesis*♦

    OpenAIRE

    Li, Hongmei; Wang, Zilai; Wang, Baiping; Guo, Qinxi; Dolios, Georgia; Tabuchi, Katsuhiko; Hammer, Robert E.; Südhof, Thomas C.; Wang, Rong; Zheng, Hui

    2010-01-01

    Proteolytic processing of the amyloid precursor protein (APP) generates large soluble APP derivatives, β-amyloid (Aβ) peptides, and APP intracellular domain. Expression of the extracellular sequences of APP or its Caenorhabditis elegans counterpart has been shown to be sufficient in partially rescuing the CNS phenotypes of the APP-deficient mice and the lethality of the apl-1 null C. elegans, respectively, leaving open the question as what is the role of the highly conserved APP intracellular...

  8. Polineuropatia nutricional entre índios Xavantes Polyneuropathy deficiency among Xavante indians

    Directory of Open Access Journals (Sweden)

    J.P.B. Vieira Filho

    1997-03-01

    polineuropatia dos Xavantes é diferente da neuropatia verificada entre os índios Kreen-Akrore e a observada entre os adolescentes índios do Parque do Xingu.The authors present two cases of polyneuropathy deficiency among Xavante indians where the sole food was rice in case 1 and almost so in case 2. The rice consumed by these indians was processed or hulled. Intoxication by cyanide from maniot or other vegetables was excluded. CASE REPORT - Two indians aged 18 and 25 years with a progressive history of weaness, decrease in muscular force and thinning were observed in their villages. On removal to the Hospital São Paulo, atrophy of the distal musculature of the upper and lower limbs, motor deficit distally with zero degree in the flexor musculature, abolished deep reflexes, plantar cutaneous reflex without response bilaterally, decreased tactile, painful and pallesthetic sensitivity distally in the lower limbs were noted on neurological examination of case 1. On neurological examination of case 2 proximal hyporeflexia in the upper limbs, areflexia in the distal portions of the upper and lower limbs, tactile and painful hypoesthesia in the feet, right hypoacousis were noted. Electromyography showed abnormalities compatible with symmetric sensorimotor polyneuropathy with an axonal demyelination pattern in case 1 and predominantly demyelinizing in case 2. Cerebrospinal fluid tests were normal. DISCUSSION - Polyneuropathy was characterized by the clinical history and by neurological, electromyographic and cerebrospinal fluid tests. The diagnosis of polyneuropathy deficiency was established by the clinical history and by electromyography suggesting peripheral polyneuropathy of nutritional origin. This neuropathy deficiency does not fit myeloneuropathies such as ataxic tropical neuropathy, spastic paraparesis and Cuba neuropathy. CONCLUSION - The Xavante polyneuropathy deficiency is caused by thiamine (vitamin B1 deficiency, that is dry beriberi, owing to consumption of

  9. Formation of amyloid fibers by monomeric light chain variable domains.

    Science.gov (United States)

    Brumshtein, Boris; Esswein, Shannon R; Landau, Meytal; Ryan, Christopher M; Whitelegge, Julian P; Phillips, Martin L; Cascio, Duilio; Sawaya, Michael R; Eisenberg, David S

    2014-10-03

    Systemic light chain amyloidosis is a lethal disease characterized by excess immunoglobulin light chains and light chain fragments composed of variable domains, which aggregate into amyloid fibers. These fibers accumulate and damage organs. Some light chains induce formation of amyloid fibers, whereas others do not, making it unclear what distinguishes amyloid formers from non-formers. One mechanism by which sequence variation may reduce propensity to form amyloid fibers is by shifting the equilibrium toward an amyloid-resistant quaternary structure. Here we identify the monomeric form of the Mcg immunoglobulin light chain variable domain as the quaternary unit required for amyloid fiber assembly. Dimers of Mcg variable domains remain stable and soluble, yet become prone to assemble into amyloid fibers upon disassociation into monomers. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Feasibility and acceptance of simultaneous amyloid PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Schuetz, Lisa; Tiepolt, Solveig; Werner, Peter; Jochimsen, Thies; Rullmann, Michael; Sattler, Bernhard; Patt, Marianne; Barthel, Henryk [Leipzig University Hospital, Department of Nuclear Medicine, Leipzig (Germany); Lobsien, Donald; Fritzsch, Dominik; Hoffmann, Karl-Titus [Leipzig University Hospital, Department of Neuroradiology, Leipzig (Germany); Schroeter, Matthias L.; Villringer, Arno [Leipzig University Hospital and Max Planck Institute for Human Cognitive and Brain Sciences, Day Clinic for Cognitive Neurology, Leipzig (Germany); Leipzig University Hospital, IFB Adiposity Diseases, Leipzig (Germany); Berrouschot, Joerg [Clinical Centre Altenburger Land, Altenburg (Germany); Saur, Dorothee; Classen, Joseph [Leipzig University Hospital, Department of Neurology, Leipzig (Germany); Hesse, Swen; Sabri, Osama [Leipzig University Hospital, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Hospital, IFB Adiposity Diseases, Leipzig (Germany); Gertz, Hermann-Josef [Leipzig University Hospital, Department of Psychiatry, Leipzig (Germany)

    2016-11-15

    Established Alzheimer's disease (AD) biomarker concepts classify into amyloid pathology and neuronal injury biomarkers, while recent alternative concepts classify into diagnostic and progression AD biomarkers. However, combined amyloid positron emission tomography/magnetic resonance imaging (PET/MRI) offers the chance to obtain both biomarker category read-outs within one imaging session, with increased patient as well as referrer convenience. The aim of this pilot study was to investigate this matter for the first time. 100 subjects (age 70 ± 10 yrs, 46 female), n = 51 with clinically defined mild cognitive impairment (MCI), n = 44 with possible/probable AD dementia, and n = 5 with frontotemporal lobe degeneration, underwent simultaneous [{sup 18}F]florbetaben or [{sup 11}C]PIB PET/MRI (3 Tesla Siemens mMR). Brain amyloid load, mesial temporal lobe atrophy (MTLA) by means of the Scheltens scale, and other morphological brain pathologies were scored by respective experts. The patients/caregivers as well as the referrers were asked to assess on a five-point scale the convenience related to the one-stop-shop PET and MRI approach. In three subjects, MRI revealed temporal lobe abnormalities other than MTLA. According to the National Institute on Aging-Alzheimer's Association classification, the combined amyloid-beta PET/MRI evaluation resulted in 31 %, 45 %, and 24 % of the MCI subjects being categorized as ''MCI-unlikely due to AD'', ''MCI due to AD-intermediate likelihood'', and ''MCI due to AD-high likelihood'', respectively. 50 % of the probable AD dementia patients were categorized as ''High level of evidence of AD pathophysiological process'', and 56 % of the possible AD dementia patients as ''Possible AD dementia - with evidence of AD pathophysiological process''. With regard to the International Working Group 2 classification, 36 subjects had both

  11. A recurrence of Guillain-Barr and eacute; syndrome or a case of acute-onset chronic inflammatory demyelinating polyneuropathy in the course of chronic hepatitis B?

    Directory of Open Access Journals (Sweden)

    Guner Celik Koyuncu

    2016-12-01

    Full Text Available Chronic inflammatory demyelinating polyneuropathy is a demyelinating polyneuropathy characterized by distal/proximal weakness, which shows gradual progression over a period of 8 weeks or longer. Guillan-Barre Syndrome is a condition characterized by acute monophasic paralysis typically following an infectious assault, and it usually peaks in severity over 3-4 weeks at most. Although rare, there are acute-onset chronic inflammatory demyelinating polyneuropathy cases that show progression over a period shorter than 4 weeks, as is the case in Guillan-Barre Syndrome .This report discusses a case of chronic inflammatory demyelinating polyneuropathy in a HBsAg-positive patient, which started as Guillan-Barre Syndrome but showed 3 recurrences within 6 months, each with rapidly progressing quadriplegia, respiratory arrest, and elevated liver enzymes and HBV DNA. [Cukurova Med J 2016; 41(4.000: 782-786

  12. A randomised, double-blinded, placebo-controlled trial of the effect of subcuta-neous immunoglobulin on muscular performance in chronic inflammatory de-myelinating polyneuropathy

    DEFF Research Database (Denmark)

    Harbo, Thomas; Markvardsen, Lars Høj; Sindrup, Søren Hein

    Objectives: Subcutaneous treatment with large amounts of immunoglobulins is feasible and effective in multifocal motor neuropathy and has been reported in a few cases in chronic inflammatory demyelinating polyneuropathy (CIDP). We hypothesized that the effect of subcutaneous treatment with immuno...

  13. Genetics Home Reference: hereditary cerebral amyloid angiopathy

    Science.gov (United States)

    ... the genes associated with hereditary cerebral amyloid angiopathy APP CST3 ITM2B Related Information What is a gene? What is a gene mutation ... a disorder seems to run in my family? What are the different ways in which a genetic condition can be inherited? More about ... APP-related Genetic Testing Registry: Dementia familial British Genetic ...

  14. Amyloid plaque formation precedes dendritic spine loss.

    Science.gov (United States)

    Bittner, Tobias; Burgold, Steffen; Dorostkar, Mario M; Fuhrmann, Martin; Wegenast-Braun, Bettina M; Schmidt, Boris; Kretzschmar, Hans; Herms, Jochen

    2012-12-01

    Amyloid-beta plaque deposition represents a major neuropathological hallmark of Alzheimer's disease. While numerous studies have described dendritic spine loss in proximity to plaques, much less is known about the kinetics of these processes. In particular, the question as to whether synapse loss precedes or follows plaque formation remains unanswered. To address this question, and to learn more about the underlying kinetics, we simultaneously imaged amyloid plaque deposition and dendritic spine loss by applying two-photon in vivo microscopy through a cranial window in double transgenic APPPS1 mice. As a result, we first observed that the rate of dendritic spine loss in proximity to plaques is the same in both young and aged animals. However, plaque size only increased significantly in the young cohort, indicating that spine loss persists even many months after initial plaque appearance. Tracking the fate of individual spines revealed that net spine loss is caused by increased spine elimination, with the rate of spine formation remaining constant. Imaging of dendritic spines before and during plaque formation demonstrated that spine loss around plaques commences at least 4 weeks after initial plaque formation. In conclusion, spine loss occurs, shortly but with a significant time delay, after the birth of new plaques, and persists in the vicinity of amyloid plaques over many months. These findings hence give further hope to the possibility that there is a therapeutic window between initial amyloid plaque deposition and the onset of structural damage at spines.

  15. Fibrillar amyloid plaque formation precedes microglial activation.

    Science.gov (United States)

    Jung, Christian K E; Keppler, Kevin; Steinbach, Sonja; Blazquez-Llorca, Lidia; Herms, Jochen

    2015-01-01

    In Alzheimer's disease (AD), hallmark β-amyloid deposits are characterized by the presence of activated microglia around them. Despite an extensive characterization of the relation of amyloid plaques with microglia, little is known about the initiation of this interaction. In this study, the detailed investigation of very small plaques in brain slices in AD transgenic mice of the line APP-PS1(dE9) revealed different levels of microglia recruitment. Analysing plaques with a diameter of up to 10 μm we find that only the half are associated with clear morphologically activated microglia. Utilizing in vivo imaging of new appearing amyloid plaques in double-transgenic APP-PS1(dE9)xCX3CR1+/- mice further characterized the dynamic of morphological microglia activation. We observed no correlation of morphological microglia activation and plaque volume or plaque lifetime. Taken together, our results demonstrate a very prominent variation in size as well as in lifetime of new plaques relative to the state of microglia reaction. These observations might question the existing view that amyloid deposits by themselves are sufficient to attract and activate microglia in vivo.

  16. Infectious particles, stress, and induced prion amyloids

    Science.gov (United States)

    2013-01-01

    Transmissible encephalopathies (TSEs) are believed by many to arise by spontaneous conversion of host prion protein (PrP) into an infectious amyloid (PrP-res, PrPSc) without nucleic acid. Many TSE agents reside in the environment, with infection controlled by public health measures. These include the disappearance of kuru with the cessation of ritual cannibalism, the dramatic reduction of epidemic bovine encephalopathy (BSE) by removal of contaminated feed, and the lack of endemic scrapie in geographically isolated Australian sheep with susceptible PrP genotypes. While prion protein modeling has engendered an intense focus on common types of protein misfolding and amyloid formation in diverse organisms and diseases, the biological characteristics of infectious TSE agents, and their recognition by the host as foreign entities, raises several fundamental new directions for fruitful investigation such as: (1) unrecognized microbial agents in the environmental metagenome that may cause latent neurodegenerative disease, (2) the evolutionary social and protective functions of different amyloid proteins in diverse organisms from bacteria to mammals, and (3) amyloid formation as a beneficial innate immune response to stress (infectious and non-infectious). This innate process however, once initiated, can become unstoppable in accelerated neuronal aging. PMID:23633671

  17. Energetics Underlying Twist Polymorphisms in Amyloid Fibrils

    NARCIS (Netherlands)

    Periole, Xavier; Huber, Thomas; Bonito-Oliva, Alessandra; Aberg, Karina C; van der Wel, Patrick C A; Sakmar, Thomas P; Marrink, Siewert J

    2018-01-01

    Amyloid fibrils are highly ordered protein aggregates associated with more than 40 human diseases. The exact conditions in which the fibrils are grown determine many types of reported fibril polymorphism, including different twist patterns. Twist-based polymorphs display unique mechanical properties

  18. Classification of amyloid status using machine learning with histograms of oriented 3D gradients

    Directory of Open Access Journals (Sweden)

    Liam Cattell

    2016-01-01

    Full Text Available Brain amyloid burden may be quantitatively assessed from positron emission tomography imaging using standardised uptake value ratios. Using these ratios as an adjunct to visual image assessment has been shown to improve inter-reader reliability, however, the amyloid positivity threshold is dependent on the tracer and specific image regions used to calculate the uptake ratio. To address this problem, we propose a machine learning approach to amyloid status classification, which is independent of tracer and does not require a specific set of regions of interest. Our method extracts feature vectors from amyloid images, which are based on histograms of oriented three-dimensional gradients. We optimised our method on 133 18F-florbetapir brain volumes, and applied it to a separate test set of 131 volumes. Using the same parameter settings, we then applied our method to 209 11C-PiB images and 128 18F-florbetaben images. We compared our method to classification results achieved using two other methods: standardised uptake value ratios and a machine learning method based on voxel intensities. Our method resulted in the largest mean distances between the subjects and the classification boundary, suggesting that it is less likely to make low-confidence classification decisions. Moreover, our method obtained the highest classification accuracy for all three tracers, and consistently achieved above 96% accuracy.

  19. Escitalopram in painful polyneuropathy: A randomized, placebo-controlled, cross-over trial

    DEFF Research Database (Denmark)

    Otto, Marit; Bach, Flemming W; Jensen, Troels S

    2008-01-01

    Serotonin (5-HT) is involved in pain modulation via descending pathways in the central nervous system. The aim of this study was to test if escitalopram, a selective serotonin reuptake inhibitor (SSRI), would relieve pain in polyneuropathy. The study design was a randomized, double-blind, placebo......-controlled cross-over trial. The daily dose of escitalopram was 20mg once daily. During the two treatment periods of 5 weeks duration, patients rated pain relief (primary outcome variable) on a 6-point ordered nominal scale. Secondary outcome measures comprised total pain and different pain symptoms (touch...... in the data analysis. Patients reported a better pain relief during treatment with escitalopram compared with placebo (p=0.001). Total pain and different pain symptoms were lower during escitalopram treatment (p=0.001-0.024). The Number needed to treat (NNT) to obtain one patient with good or complete pain...

  20. Treatment of Chronic Inflammatory Demyelinating Polyneuropathy: From Molecular Bases to Practical Considerations

    Directory of Open Access Journals (Sweden)

    Paolo Ripellino

    2014-01-01

    Full Text Available Chronic inflammatory demyelinating polyneuropathy (CIDP is an autoimmune disease of the peripheral nervous system, in which both cellular and humoral immune responses are involved. The disease is clinically heterogeneous with some patients displaying pure motor form and others also showing a variable degree of sensory dysfunction; disease evolution may also differ from patient to patient, since monophasic, progressive, and relapsing forms are reported. Underlying such clinical variability there is probably a broad spectrum of molecular dysfunctions that are and will be the target of therapeutic strategies. In this review we first explore the biological bases of current treatments and subsequently we focus on the practical management that must also take into account pharmacoeconomic issues.

  1. Acute Demyelinating Polyneuropathy after Lung Transplantation: Guillain-Barré Syndrome or Tacrolimus Toxicity?

    Directory of Open Access Journals (Sweden)

    Nirmal S. Sharma

    2014-01-01

    Full Text Available Guillain-Barré syndrome (GBS has been described after solid organ and bone marrow transplantation mostly due to viral infections and possibly calcineurin inhibitors. Incidence after bone marrow transplant is 0.3–0.7%, though incidence in other transplants is not well known. We present the first description of tacrolimus associated GBS in lung transplant recipients in the English language literature. The pathophysiology of tacrolimus-induced polyneuropathy is not known, but some have hypothesized that tacrolimus induces an inflammatory phenomenon by differential effects on T cell subsets. Diagnosis of association may be challenging and requires high index of suspicion. The optimal treatment of GBS-associated with tacrolimus after lung transplantation is unknown, although drug discontinuation may result in improvement in some patients, while some reports suggest that the use of IVIG and/or plasmapheresis may be helpful and safe in organ transplant recipients with severe symptoms.

  2. Acute axonal polyneuropathy with predominant proximal involvement: an uncommon neurological complication of bariatric surgery

    Directory of Open Access Journals (Sweden)

    Machado Flavia Costa Nunes

    2006-01-01

    Full Text Available Bariatric surgery is frequently indicated in the treatment of morbid obesity. Previously unreported complications have been associated to this surgery; among them, neurological complications have gained attention. We report the case of a 25-year-old man submitted to gastric surgery for treatment of morbid obesity who developed, two months after surgery, acute proximal weakness in lower limbs. The electroneuromyography revealed axonal peripheral polyneuropathy with predominant proximal involvement. After treatment with immunoglobulin and vitamin supplementation, rapid clinical and neurophysiologic recovery was observed. We describe the clinical and electroneuromyographic features of this case, stressing the difficulty of initial diagnosis, particularly in the differential diagnosis with Guillain-Barré syndrome. We discuss the importance of nutritional follow-up and the eventual indication of routine vitamin supplementation in these patients.

  3. Resistance training and aerobic training improve muscle strength and aerobic capacity in chronic inflammatory demyelinating polyneuropathy

    DEFF Research Database (Denmark)

    Markvardsen, Lars H; Overgaard, Kristian; Heje, Karen

    2018-01-01

    INTRODUCTION: We investigated the effects of aerobic and resistance exercise in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: Eighteen CIDP patients treated with subcutaneous immunoglobulin performed 12 weeks of aerobic exercise and 12 weeks of resistance exercise...... after a run-in period of 12 weeks without exercise. Three times weekly the participants performed aerobic exercise on an ergometer bike or resistance exercise with unilateral training of knee and elbow flexion/extension. Primary outcomes were maximal oxygen consumption velocity (VO2 -max) and maximal...... resulted in an increase of 13.8% ± 16.0% (P = 0.0004) in cIKS. DISCUSSION: Aerobic exercise training and resistance exercise training improve fitness and strength in CIDP patients. Muscle Nerve, 2017....

  4. Vocal Cord Paralysis and Hypercapnic Respiratory Failure in a Patient with Familial Amyloidotic Polyneuropathy.

    Science.gov (United States)

    Pıhtılı, Aylin; Bingol, Züleyha; Durmuş, Hacer; Parman, Yeşim; Kıyan, Esen

    2016-01-01

    We herein report a patient case with familial amyloidotic polyneuropathy (FAP) who presented with vocal cord paralysis (VCP). A 60-year-old man with FAP (Gly89Gln) presented with hoarseness and snoring for the previous two years. A chest X-ray demonstrated cardiomegaly and bilateral diaphragmatic elevation. The findings of a restrictive pattern on spirometry and daytime hypercapnia were consistent with respiratory muscle weakness related to neuropathy [forced expiratory volume (FEV1): 38%, forced vital capacity (FVC): 39%, FEV1/FVC: 77, partial pressure of arterial oxygen (PaO2): 80 mmHg, partial pressure of carbon dioxide in arterial blood (PaCO2): 52 mmHg]. An ear-nose-throat examination showed VCP. Polysomnography revealed severe obstructive sleep apnea (OSA). FAP may cause OSA by VCP and hypercapnic respiratory failure by respiratory muscle weakness. Therefore, an ear-nose-throat examination, spirometry, arterial blood gases analysis and polysomnography are important for these patients.

  5. Critical illness myopathy and polyneuropathy - A challenge for physiotherapists in the intensive care units.

    Science.gov (United States)

    Pattanshetty, Renu B; Gaude, Gajanan S

    2011-04-01

    The development of critical patient related generalized neuromuscular weakness, referred to as critical illness polyneuropathy (CIP) and critical illness myopathy (CIM), is a major complication in patients admitted to intensive care units (ICU). Both CIP and CIM cause muscle weakness and paresis in critically ill patients during their ICU stay. Early mobilization or kinesiotherapy have shown muscle weakness reversion in critically ill patients providing faster return to function, reducing weaning time, and length of hospitalization. Exercises in the form of passive, active, and resisted forms have proved to improve strength and psychological well being. Clinical trials using neuromuscular electrical stimulation to increase muscle mass, muscle strength and improve blood circulation to the surrounding tissue have proved beneficial. The role of electrical stimulation is unproven as yet. Recent evidence indicates no difference between treated and untreated muscles. Future research is recommended to conduct clinical trials using neuromuscular electrical stimulation, exercises, and early mobilization as a treatment protocol in larger populations of patients in ICU.

  6. Biomathematical screening of amyloid radiotracers with clinical usefulness index.

    Science.gov (United States)

    Nai, Ying-Hwey; Shidahara, Miho; Seki, Chie; Watabe, Hiroshi

    2017-11-01

    To facilitate radiotracers' development, a screening methodology using a biomathematical model and clinical usefulness index (CUI) was proposed to evaluate radiotracers' diagnostic capabilities. A total of 31 amyloid positron emission tomography radiotracers were evaluated. A previously developed biomathematical model was used to simulate 1000 standardized uptake value ratios with population and noise simulations, which were used to determine the integrated receiver operating characteristics curve (Az), effect size (Es), and standardized uptake value ratio (Sr) of conditions-pairs of healthy control-mild cognitive impaired and mild cognitive impaired-Alzheimer's disease. CUI was obtained from the product of averaged [Formula: see text], [Formula: see text], and [Formula: see text]. The relationships of [Formula: see text], [Formula: see text], and [Formula: see text] with CUI were different, suggesting that they assessed different radiotracer properties. The combination of Az, Es, and Sr complemented each other and resulted in CUI of 0.10 to 5.72, with clinically applied amyloid positron emission tomography radiotracers having CUI greater than 3.0. The CUI rankings of clinically applied radiotracers were close to their reported clinical results, attesting to the applicability of the screening methodology.

  7. Serum amyloid A protein in amyloidosis, rheumatic, and neoplastic diseases

    International Nuclear Information System (INIS)

    Benson, M.D.; Cohen, A.S.

    1979-01-01

    Serum levels of amyloid protein A (SAA) have been shown to be elevated in different types of amyloidosis and in rheumatic diseases by radioimmunoassay using 125 iodine labeled AA and anti-AA. SAA levels were elevated in both primary and secondary amyloidosis, but there were highly significant differences between these levels. In heredofamilial amyloid, SAA levels were within normal limits. While the mean SAA level was elevated in persons over 70 years, the fact that some persons in this age group had normal levels suggested that marked elevation after age 70 may be due to occult inflammatory or neoplastic disease. High SAA levels in patients with rheumatoid arthritis correlated, in most cases, with physician evaluation of disease activity and Westergren ESR. SAA levels in patients with systemic lupus erythematosus were lower than those in patients with rheumatoid arthritis, and most patients with degenerative joint disease had normal levels. Very high levels of SAA were found in patients with neoplastic diseases. Patients with carcinoma of the lung and bowel had much higher levels than patients with carcinoma of the breast. Determination of SAA levels may be of value in evaluating different forms of systemic amyloidosis, assessing the activity of rheumatic disease, and screening for occult inflammatory or neoplastic disease

  8. Objective evidence that small-fiber polyneuropathy underlies some illnesses currently labeled as fibromyalgia

    Science.gov (United States)

    Oaklander, Anne Louise; Herzog, Zeva Daniela; Downs, Heather; Klein, Max M.

    2013-01-01

    Fibromyalgia is a common, disabling, syndrome that includes chronic widespread pain plus other diverse symptoms. No specific objective abnormalities have been identified, precluding definitive testing, disease-modifying treatments, and identification of causes. In contrast, small-fiber polyneuropathy (SFPN), despite causing similar symptoms, is definitionally a disease caused by dysfunction and degeneration of peripheral small-fiber neurons. SFPN has established etiologies, some diagnosable and definitively treatable, e.g., diabetes. To evaluate the hypothesis that some patients labeled with “fibromyalgia” have unrecognized SFPN causing their illness symptoms, we analyzed SFPN-associated symptoms, signs, and pathological and physiological markers in 27 fibromyalgia patients and 30 matched normal controls. Fibromyalgia subjects had to satisfy American College of Rheumatology criteria plus present documented evidence of a physician’s actual fibromyalgia diagnosis. Study instruments comprised the Michigan Neuropathy Screening Instrument (MNSI), the Utah Early Neuropathy Scale (UENS), distal-leg neurodiagnostic skin biopsies, plus autonomic-function testing (AFT). 41% of skin biopsies from fibromyalgia subjects vs. 3% of biopsies from control subjects were diagnostic for SFPN, and MNSI and UENS scores were higher among fibromyalgia than control subjects (all P ≤ 0.001). Abnormal AFTs were equally prevalent suggesting that fibromyalgia-associated SFPN is primarily somatic. Blood tests from all 13 fibromyalgia subjects with SFPN-diagnostic skin biopsies provided insights into etiologies. All glucose tolerance tests were normal, but eight subjects had dysimmune markers, 2 had hepatitis C serologies, and one family had apparent genetic causality. These findings suggest that some patients with chronic pain labeled as “fibromyalgia” have unrecognized small-fiber polyneuropathy, a distinct disease that can be objectively tested for and sometimes definitively

  9. Whole-body MR neurography: Prospective feasibility study in polyneuropathy and Charcot-Marie-Tooth disease.

    Science.gov (United States)

    Chhabra, Avneesh; Carrino, John A; Farahani, Sahar J; Thawait, Gaurav K; Sumner, Charlotte J; Wadhwa, Vibhor; Chaudhary, Vinay; Lloyd, Thomas E

    2016-12-01

    To evaluate the feasibility of whole-body magnetic resonance neurography (WBMRN) in polyneuropathy for technical feasibility, distribution of nerve abnormalities, and differentiation. Twenty WBMRN examinations were performed on a 3T scanner over 2 years. Patient demographics including history of hereditary and acquired neuropathy were recorded. The images were evaluated by two independent readers with nerve imaging experience for quality. The nerve signal and size alterations were measured in the brachial plexus, lumbosacral plexus, and femoral and sciatic nerves; diffusion tensor imaging parameters (fractional anisotropy [FA] and apparent diffusion coefficient [ADC]) were determined in plexuses, and tractography was performed. Nonparametric Wilcoxon rank sum test, receiver operating characteristic (ROC) analysis, and intraclass correlation coefficients (ICCs) were obtained. Excellent image quality was obtained for the majority of lumbosacral (LS) plexus (18/20) and 50% of brachial plexus (10/20) regions. Qualitatively among cases, the nerve hyperintensity and/or thickening involved the brachial plexus (11/11), LS plexus (7/11), and both plexuses (7/11), with most nerve thickenings observed in Charcot-Marie-Tooth disease type 1. The nerve signal intensity alterations were significantly different for both brachial (P < 0.05) and LS (P < 0.05) plexuses in cases versus controls. The femoral and sciatic nerve size alterations were different (P < 0.05), while signal intensity differences were not significant (P = 0.1-0.97). Transverse dimensions of C8 (4 mm), L5 (6.2 mm) and S1 (5.1 mm) nerve roots, and sciatic nerves (10.2 mm) were the most accurate diagnostic performance measures in distinguishing cases from controls. WBMRN is feasible for use in the clinical practice for the identification and potential characterization of polyneuropathy. J. Magn. Reson. Imaging 2016;44:1513-1521. © 2016 International Society for Magnetic Resonance in Medicine.

  10. Sensorimotor polyneuropathy

    Science.gov (United States)

    ... that may slip on the floor). Test water temperature before bathing. Use railings. Wear protective shoes (such ... In some cases, you can fully recover from peripheral neuropathy if your provider can find the cause ...

  11. A Peptide Derived from the HIV-1 gp120 Coreceptor-Binding Region Promotes Formation of PAP248-286 Amyloid Fibrils to Enhance HIV-1 Infection.

    Directory of Open Access Journals (Sweden)

    Jinquan Chen

    Full Text Available Semen is a major vehicle for HIV transmission. Prostatic acid phosphatase (PAP fragments, such as PAP248-286, in human semen can form amyloid fibrils to enhance HIV infection. Other endogenous or exogenous factors present during sexual intercourse have also been reported to promote the formation of seminal amyloid fibrils.Here, we demonstrated that a synthetic 15-residue peptide derived from the HIV-1 gp120 coreceptor-binding region, designated enhancing peptide 2 (EP2, can rapidly self-assemble into nanofibers. These EP2-derivated nanofibers promptly accelerated the formation of semen amyloid fibrils by PAP248-286, as shown by Thioflavin T (ThT and Congo red assays. The amyloid fibrils presented similar morphology, assessed via transmission electron microscopy (TEM, in the presence or absence of EP2. Circular dichroism (CD spectroscopy revealed that EP2 accelerates PAP248-286 amyloid fibril formation by promoting the structural transition of PAP248-286 from a random coil into a cross-β-sheet. Newly formed semen amyloid fibrils effectively enhanced HIV-1 infection in TZM-bl cells and U87 cells by promoting the binding of HIV-1 virions to target cells.Nanofibers composed of EP2 promote the formation of PAP248-286 amyloid fibrils and enhance HIV-1 infection.

  12. β-Amyloid burden in healthy aging: regional distribution and cognitive consequences.

    Science.gov (United States)

    Rodrigue, K M; Kennedy, K M; Devous, M D; Rieck, J R; Hebrank, A C; Diaz-Arrastia, R; Mathews, D; Park, D C

    2012-02-07

    Several lines of evidence suggest that pathologic changes underlying Alzheimer disease (AD) begin years prior to the clinical expression of the disease, underscoring the need for studies of cognitively healthy adults to capture these early changes. The overall goal of the current study was to map the cortical distribution of β-amyloid (Aβ) in a healthy adult lifespan sample (aged 30-89), and to assess the relationship between elevated amyloid and cognitive performance across multiple domains. A total of 137 well-screened and cognitively normal adults underwent Aβ PET imaging with radiotracer (18)F-florbetapir. Aβ load was estimated from 8 cortical regions. Participants were genotyped for APOE and tested for processing speed, working memory, fluid reasoning, episodic memory, and verbal ability. Aβ deposition is distributed differentially across the cortex and progresses at varying rates with age across cortical brain regions. A subset of cognitively normal adults aged 60 and over show markedly elevated deposition, and also had a higher rate of APOE ε4 (38%) than nonelevated adults (19%). Aβ burden was linked to poorer cognitive performance on measures of processing speed, working memory, and reasoning. Even in a highly selected lifespan sample of adults, Aβ deposition is apparent in some adults and is influenced by APOE status. Greater amyloid burden was related to deleterious effects on cognition, suggesting that subtle cognitive changes accrue as amyloid progresses.

  13. Neuroprotective and nootropic drug noopept rescues α-synuclein amyloid cytotoxicity.

    Science.gov (United States)

    Jia, Xueen; Gharibyan, Anna L; Öhman, Anders; Liu, Yonggang; Olofsson, Anders; Morozova-Roche, Ludmilla A

    2011-12-16

    Parkinson's disease is a common neurodegenerative disorder characterized by α-synuclein (α-Syn)-containing Lewy body formation and selective loss of dopaminergic neurons in the substantia nigra. We have demonstrated the modulating effect of noopept, a novel proline-containing dipeptide drug with nootropic and neuroprotective properties, on α-Syn oligomerization and fibrillation by using thioflavin T fluorescence, far-UV CD, and atomic force microscopy techniques. Noopept does not bind to a sterically specific site in the α-Syn molecule as revealed by heteronuclear two-dimensional NMR analysis, but due to hydrophobic interactions with toxic amyloid oligomers, it prompts their rapid sequestration into larger fibrillar amyloid aggregates. Consequently, this process rescues the cytotoxic effect of amyloid oligomers on neuroblastoma SH-SY5Y cells as demonstrated by using cell viability assays and fluorescent staining of apoptotic and necrotic cells and by assessing the level of intracellular oxidative stress. The mitigating effect of noopept against amyloid oligomeric cytotoxicity may offer additional benefits to the already well-established therapeutic functions of this new pharmaceutical. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. AURAMINE O AS POTENTIAL AMYLOID MARKER: FLUORESCENCE AND MOLECULAR DOCKING STUDIES

    Directory of Open Access Journals (Sweden)

    K. Vus

    2017-10-01

    Full Text Available The applicability of Auramine O to the detection and characterization of lysozyme and serum albumin amyloid fibrils has been assessed using the fluorimetric titration and molecular docking. The parameters of the dye binding to native and fibrillar proteins were estimated in terms of the Langmuir adsorption model. It was found that Auramine O displays the high affinity for amyloid fibrils, being of the same order of magnitude as that of the classical amyloid markers. The dye also showed greater fluorescence response to lysozyme fibrils and lower sensitivity to the native protein, than Thioflavin T. Furthermore, unlike Thioflavin T, Auramine O was able to detect the morphological differences between lysozyme and albumin fibrils due to the shifts in the position of the emission maxima of the fibril-incorporated fluorophore. The molecular docking studies revealed that Auramine O and Thioflavin T form the most stable complexes with the G54_L56/S60_W62 groove of lysozyme fibrils, running parallel to the fibril axis. The results obtained suggest the contribution of both hydrophobic and electrostatic interactions to the stabilization of the dye complexes with amyloid fibrils.

  15. Cerebral Amyloid Angiopathy-Related Inflammation: Report of a Case with Very Difficult Therapeutic Management

    Directory of Open Access Journals (Sweden)

    Francesca Crosta

    2015-01-01

    Full Text Available Background. Cerebral amyloid angiopathy-related inflammation (CAA-ri results from autoimmune response to beta-amyloid deposits in cerebral vessels. Its clinical course and complications have seldom been described in literature. Case Report. In a patient presenting with delirium and left hemiparesis the diagnosis of CAA-ri was supported by the finding of elevated anti-amyloid autoantibodies in the cerebrospinal fluid (CSF. Steroid therapy produced significant improvements in clinical and investigational assessments, but after two months, it caused Acute Respiratory Distress Syndrome. After steroid therapy discontinuation the patient presented a rapidly progressive dementia, Guillain-Barré syndrome, new cerebral ischemic lesions, and thrombosis of the right cephalic and subclavian veins that were treated with subcutaneous heparin. After a week the patient died because of brain hemorrhage. Conclusion. This case suggests caution in steroid therapy discontinuation and antithrombotic therapy administration in patients with CAA-ri. The CSF search of anti-amyloid autoantibodies could be helpful to support the diagnosis.

  16. [Landry-type motor polyneuropathy and spinal transection syndrome with flaccid paraplegia. Rare neurological syndromes in panarteritis nodosa].

    Science.gov (United States)

    Patzold, U; Haller, P

    1975-03-07

    In a 59-year-old man in complete health a pure motor polyneuropathic syndrome with quadruplegia, swallowing and respiratory paralysis developed over a few hours. A few days later he died with the clinical picture of septicaemia. In a 59-year-old woman who had been investigated and treated for a suspected carcinoma for several months a predominantly distal sensomotoric polyneuropathy syndrome developed. The further course of disease was completely misleading as regards the diagnosis due to an acutely occurring transection syndrome with flaccid paraplegia, loss of reflexes, and bladder and rectal paralysis. Due to the very unusual neurological symptoms panarteritis nodosa was only diagnosed at autopsy and by histology in both cases. Panarteritis nodosa must be considered as a differential diagnosis in Landry-type polyneuropathy as well as in an acute spinal transection syndrome. The first patient demonstrates toxic damages, the second vascular damages of the nervous system which in general determine the neurological symptomatology of this vascular disease.

  17. Chemical Methods to Knock Down the Amyloid Proteins

    Directory of Open Access Journals (Sweden)

    Na Gao

    2017-06-01

    Full Text Available Amyloid proteins are closely related with amyloid diseases and do tremendous harm to human health. However, there is still a lack of effective strategies to treat these amyloid diseases, so it is important to develop novel methods. Accelerating the clearance of amyloid proteins is a favorable method for amyloid disease treatment. Recently, chemical methods for protein reduction have been developed and have attracted much attention. In this review, we focus on the latest progress of chemical methods that knock down amyloid proteins, including the proteolysis-targeting chimera (PROTAC strategy, the “recognition-cleavage” strategy, the chaperone-mediated autophagy (CMA strategy, the selectively light-activatable organic and inorganic molecules strategy and other chemical strategies.

  18. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Vad, Brian S; Dueholm, Morten S

    2015-01-01

    The success of Pseudomonas species as opportunistic pathogens derives in great part from their ability to form stable biofilms that offer protection against chemical and mechanical attack. The extracellular matrix of biofilms contains numerous biomolecules, and it has recently been discovered...... that in Pseudomonas one of the components includes β-sheet rich amyloid fibrils (functional amyloid) produced by the fap operon. However, the role of the functional amyloid within the biofilm has not yet been investigated in detail. Here we investigate how the fap-based amyloid produced by Pseudomonas affects biofilm...... hydrophobicity and mechanical properties. Using atomic force microscopy imaging and force spectroscopy, we show that the amyloid renders individual cells more resistant to drying and alters their interactions with hydrophobic probes. Importantly, amyloid makes Pseudomonas more hydrophobic and increases biofilm...

  19. Calumenin interacts with serum amyloid P component

    DEFF Research Database (Denmark)

    Vorum, H; Jacobsen, Christian; Honoré, Bent

    2000-01-01

    We recently reported the identification of human calumenin, a novel Ca(2+) binding, transformation-sensitive and secreted protein [Vorum et al. (1998) Biochim. Biophys. Acta 1386, 121-131; Vorum et al. (1999) Exp. Cell Res. 248, 473-481] belonging to the family of multiple EF-hand proteins...... with calumenin in the presence of Ca(2+). Amino acid sequencing identified this protein as serum amyloid P component (SAP). Furthermore, we verified and characterized the calumenin-SAP interaction by the surface plasmon resonance technique. The findings indicate that calumenin may participate...... in the immunological defense system and could be involved in the pathological process of amyloidosis that leads to formation of amyloid deposits seen in different types of tissues. Udgivelsesdato: 2000-Jan-14...

  20. Les Polyneuropathies Chez Les Patients Infectés Par Le Vih À L\\'ère ...

    African Journals Online (AJOL)

    Les polyneuropathies (PN) figurent parmi les complications neurologiques les plus fréquentes au cours de l\\'infection par le virus de l\\'immunodéficience humaine (VIH). Elles peuvent être en rapport avec le VIH lui-même en raison de son neurotropisme propre ou être la conséquence de la neurotoxicité des antirétroviraux ...

  1. Mesenchymal Stem Cell-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Ameliorate Diabetic Polyneuropathy in Mice

    OpenAIRE

    Himeno, Tatsuhito; Kamiya, Hideki; Naruse, Keiko; Cheng, Zhao; Ito, Sachiko; Kondo, Masaki; Okawa, Tetsuji; Fujiya, Atsushi; Kato, Jiro; Suzuki, Hirohiko; Kito, Tetsutaro; Hamada, Yoji; Oiso, Yutaka; Isobe, Kenichi; Nakamura, Jiro

    2013-01-01

    Background. Although pathological involvements of diabetic polyneuropathy (DPN) have been reported, no dependable treatment of DPN has been achieved. Recent studies have shown that mesenchymal stem cells (MSCs) ameliorate DPN. Here we demonstrate a differentiation of induced pluripotent stem cells (iPSCs) into MSC-like cells and investigate the therapeutic potential of the MSC-like cell transplantation on DPN. Research Design and Methods. For induction into MSC-like cells, GFP-expressing iPSC...

  2. What is the role of amyloid precursor protein dimerization?

    OpenAIRE

    Khalifa, Naouel Ben; Van Hees, Joanne; Tasiaux, Bernadette; Huysseune, Sandra; Smith, Steven O.; Constantinescu, Stefan N.; Octave, Jean-Noël; Kienlen-Campard, Pascal

    2010-01-01

    Extensive research efforts have been conducted over the past decades to understand the processing of the Amyloid Precursor Protein (APP). APP cleavage leads to the production of the beta-amyloid peptide (Abeta), which is the major constituent of the amyloid core of senile plaques found in the brains of patients with Alzheimer's disease (AD). Abeta is produced by the sequential cleavage of APP by beta- and gamma-secretases. Cleavage of APP by gamma-secretase also generates the APP Intracellula...

  3. Strong transthyretin immunostaining: potential pitfall in cardiac amyloid typing.

    Science.gov (United States)

    Satoskar, Anjali A; Efebera, Yvonne; Hasan, Ayesha; Brodsky, Sergey; Nadasdy, Gyongyi; Dogan, Ahmet; Nadasdy, Tibor

    2011-11-01

    Although systemic amyloidosis commonly presents with renal disease, cardiac involvement usually determines the patient's prognosis. Cardiac involvement is seen in light chain amyloid and transthyretin amyloidosis. Distinguishing between these two is critical because prognosis and treatment differ. Our study demonstrates the unreliability of transthyretin immunostaining in subtyping cardiac amyloid. Between January 2003 and August 2010, we retrieved 229 native endomyocardial biopsies, of which 24 had amyloid. Immunohistochemistry for κ, λ, transthyretin, and serum amyloid A protein was performed on formalin-fixed, paraffin-embedded sections. Staining was graded as weak (trace to 1+) or strong (2 to 3+). Mass spectrometry (MS)-based proteomic typing of microdissected amyloid material was performed on selected cases. Fifteen patients had monoclonal gammopathy/plasma cell dyscrasia with cardiac amyloid. Eight of them (53%) showed strong transthyretin staining in the cardiac amyloid deposits. MS was performed in 5 of these 8 biopsies, and all 5 biopsies revealed light chain amyloid-type amyloid. Two of these 5 light chain amyloid biopsies did not even have concomitant strong staining for the appropriate light chain. Among the 15 cases with plasma cell dyscrasia, only 7 biopsies showed strong staining for the corresponding monoclonal light chain. Strong, false-positive immunostaining for transthyretin in cardiac amyloid is a potential pitfall, augmented by the frequent lack of staining for immunoglobulin light chains. Therefore, the presence of amyloid in the cardiac biopsy should prompt a search for plasma cell dyscrasia irrespective of transthyretin staining. Confirmation with MS should be sought, particularly if there is any discrepancy between κ/λ staining and serum immunofixation results.

  4. Generation of amyloid-β is reduced by the interaction of calreticulin with amyloid precursor protein, presenilin and nicastrin.

    Directory of Open Access Journals (Sweden)

    Nina Stemmer

    Full Text Available Dysregulation of the proteolytic processing of amyloid precursor protein by γ-secretase and the ensuing generation of amyloid-β is associated with the pathogenesis of Alzheimer's disease. Thus, the identification of amyloid precursor protein binding proteins involved in regulating processing of amyloid precursor protein by the γ-secretase complex is essential for understanding the mechanisms underlying the molecular pathology of the disease. We identified calreticulin as novel amyloid precursor protein interaction partner that binds to the γ-secretase cleavage site within amyloid precursor protein and showed that this Ca(2+- and N-glycan-independent interaction is mediated by amino acids 330-344 in the C-terminal C-domain of calreticulin. Co-immunoprecipitation confirmed that calreticulin is not only associated with amyloid precursor protein but also with the γ-secretase complex members presenilin and nicastrin. Calreticulin was detected at the cell surface by surface biotinylation of cells overexpressing amyloid precursor protein and was co-localized by immunostaining with amyloid precursor protein and presenilin at the cell surface of hippocampal neurons. The P-domain of calreticulin located between the N-terminal N-domain and the C-domain interacts with presenilin, the catalytic subunit of the γ-secretase complex. The P- and C-domains also interact with nicastrin, another functionally important subunit of this complex. Transfection of amyloid precursor protein overexpressing cells with full-length calreticulin leads to a decrease in amyloid-β42 levels in culture supernatants, while transfection with the P-domain increases amyloid-β40 levels. Similarly, application of the recombinant P- or C-domains and of a synthetic calreticulin peptide comprising amino acid 330-344 to amyloid precursor protein overexpressing cells result in elevated amyloid-β40 and amyloid-β42 levels, respectively. These findings indicate that the interaction of

  5. Development of magnetic resonance imaging based detection methods for beta amyloids via sialic acid-functionalized magnetic nanoparticles

    Science.gov (United States)

    Kouyoumdjian, Hovig

    The development of a non-invasive method for the detection of Alzheimer's disease is of high current interest, which can be critical in early diagnosis and in guiding preventive treatment of the disease. The aggregates of beta amyloids are a pathological hallmark of Alzheimer's disease. Carbohydrates such as sialic acid terminated gangliosides have been shown to play significant roles in initiation of amyloid aggregation. Herein, we report a biomimetic approach using sialic acid coated iron oxide superparamagnetic nanoparticles for in vitro detection in addition to the assessment of the in vivo mouse-BBB (Blood brain barrier) crossing of the BSA (bovine serum albumin)-modified ones. The sialic acid functionalized dextran nanoparticles were shown to bind with beta amyloids through several techniques including ELISA (enzyme linked immunosorbent assay), MRI (magnetic resonance imaging), TEM (transmission electron microscopy), gel electrophoresis and tyrosine fluorescence assay. The superparamagnetic nature of the nanoparticles allowed easy detection of the beta amyloids in mouse brains in both in vitro and ex vivo model by magnetic resonance imaging. Furthermore, the sialic acid nanoparticles greatly reduced beta amyloid induced cytotoxicity to SH-SY5Y neuroblastoma cells, highlighting the potential of the glyconanoparticles for detection and imaging of beta amyloids. Sialic acid functionalized BSA (bovine serum albumin) nanoparticles also showed significant binding to beta amyloids, through ELISA and ex vivo mouse brain MRI experiments. Alternatively, the BBB crossing was demonstrated by several techniques such as confocal microscopy, endocytosis, exocytosis assays and were affirmed by nanoparticles transcytosis assays through bEnd.3 endothelial cells. Finally, the BBB crossing was confirmed by analyzing the MRI signal of nanoparticle-injected CD-1 mice.

  6. Amyloid-hydroxyapatite bone biomimetic composites.

    Science.gov (United States)

    Li, Chaoxu; Born, Anne-Kathrin; Schweizer, Thomas; Zenobi-Wong, Marcy; Cerruti, Marta; Mezzenga, Raffaele

    2014-05-28

    A "bottom up" strategy is proposed to synthesize high aspect ratio hydroxyapatite (and brushite) platelets, and combine them with amyloid fibrils into layered hybrid nanocomposites. Their hierarchical structure, despite the differences from natural bone, confers to the nanocomposites a density and elastic modulus matching those of cancellous bone. Evidence of good adhesion and spreading of human trabecular bone-derived pre-osteoblasts cells on these nanocomposites is provided. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Beta-amyloid and cholinergic neurons

    Czech Academy of Sciences Publication Activity Database

    Doležal, Vladimír; Kašparová, Jana

    2003-01-01

    Roč. 28, 3-4 (2003), s. 499-506 ISSN 0364-3190 R&D Projects: GA ČR GA305/01/0283; GA AV ČR IAA5011206 Institutional research plan: CEZ:AV0Z5011922 Keywords : cholinergic neurons * AlzheimerŽs disease * beta-amyloid Subject RIV: FH - Neurology Impact factor: 1.511, year: 2003

  8. Amyloid Beta Peptide Folding in Reverse Micelles.

    Science.gov (United States)

    Eskici, Gözde; Axelsen, Paul H

    2017-07-19

    Previously published experimental studies have suggested that when the 40-residue amyloid beta peptide is encapsulated in a reverse micelle, it folds into a structure that may nucleate amyloid fibril formation (Yeung, P. S.-W.; Axelsen, P. H. J. Am. Chem. Soc. 2012, 134, 6061 ). The factors that induce the formation of this structure have now been identified in a multi-microsecond simulation of the same reverse micelle system that was studied experimentally. Key features of the polypeptide-micelle interaction include the anchoring of a hydrophobic residue cluster into gaps in the reverse micelle surface, the formation of a beta turn at the anchor point that brings N- and C-terminal segments of the polypeptide into proximity, high ionic strength that promotes intramolecular hydrogen bond formation, and deformation of the reverse micelle surface to facilitate interactions with the surface along the entire length of the polypeptide. Together, these features cause the simulation-derived vibrational spectrum to red shift in a manner that reproduces the red-shift previously reported experimentally. On the basis of these findings, a new mechanism is proposed whereby membranes nucleate fibril formation and facilitate the in-register alignment of polypeptide strands that is characteristic of amyloid fibrils.

  9. Design and Construction of Large Amyloid Fibers

    Directory of Open Access Journals (Sweden)

    Devin M. Ridgley

    2015-04-01

    Full Text Available Mixtures of “template” and “adder” proteins self-assemble into large amyloid fibers of varying morphology and modulus. Fibers range from low modulus, rectangular cross-sectioned tapes to high modulus, circular cross-sectioned cylinders. Varying the proteins in the mixture can elicit “in-between” morphologies, such as elliptical cross-sectioned fibers and twisted tapes, both of which have moduli in-between rectangular tapes and cylindrical fibers. Experiments on mixtures of proteins of known amino acid sequence show that control of the large amyloid fiber morphology is dependent on the amount of glutamine repeats or “Q-blocks” relative to hydrophobic side chained amino acids such as alanine, isoleucine, leucine, and valine in the adder protein. Adder proteins with only hydrophobic groups form low modulus rectangular cross-sections and increasing the Q-block content allows excess hydrogen bonding on amide groups that results in twist and higher modulus. The experimental results show that large amyloid fibers of specific shape and modulus can be designed and controlled at the molecular level.

  10. Amyloid osteoarthropathy in long term hemodialysis patients

    International Nuclear Information System (INIS)

    Orzincolo, C.; Cardona, P.; Vita, G.; Bedani, P.L.; Farinelli, A.; Scutellari, P.N.

    1988-01-01

    The accumulation of amyloid in the bone and joint system has recently been recognized as a peculiar disease in patients undergoing long-term hemodialysis (5 years at least), especially in those who use cuprophan membranes. The pathology of amyloidosis is characterized by deposits of amyloid (β microglobulin mainly) in the bone, in the synovia, and in pericapsular soft tissues. The skeleton of 46 long-term hemodialysis patients (19 males and 27 females) was studied by X-ray; bone and joint abnormalities due to amyloid deposition were observed in 45% of cases. The shoulder, hip, and wrist were the most frequently involved joints. Destructive spondyloarthorapathy was present in 15% of cases. The radiographic patterns of AOD are generally divided into axial and peripheral lesions. In the appendicular skeleton abnormalities include: well-defined lytic areas (geodes), pathologic fractures, marginal erosions, and particular soft tissue swelling. Destructive spondyloarthropathy is frequently present in the cervical spine (85% of our cases) and is characterized by narrowing of the invertebral space, marginal erosion, and subchondral bone sclerosis of the vertebral body

  11. Amyloid goiter: two cases and a review of the Literature

    International Nuclear Information System (INIS)

    Yildiz, Levent; Kefeli, Mehmet; Kose, Behiye; Baris, Sancar

    2007-01-01

    Although involvement of the thyroid gland by amyloid is a relatively common phenomenon, clinically significant enlargement of the thyroid owing to amyloid deposition is an extremely rare occurrence. We describe two cases of amyloid goiter and review the relevant literature. The first case was systemic amylloidosis secondary to familial Mediterranean fever. The second case was a chronic renal failure patient who presented with an enlarged thyroid and upper airway obstructive symptoms. To date, true amyloid goiter secondary to amyloidosis associated with familial Mediterranean fever has only been reported in twelve patients. (author)

  12. Amyloid-plaque imaging in diagnosis of dementia; Amyloidplaque-Bildgebung in der Demenzdiagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Drzezga, A. [Klinikum rechts der Isar, Technische Univ. Muenchen (Germany). Nuklearmedizinische Klinik

    2009-06-15

    The increasing life-expectancy of our society results in a continuously growing number of patients suffering from dementing disorders, particularly Alzheimer's disease (AD). Apart from the deleterious consequences for the patients and their relatives, this has also alarming effects on our social systems. These facts have justified increased scientific efforts regarding the identification of basic pathomechanisms of dementia and the development of new treatment options. Increased production of specific proteins and their pathologic aggregation in the brain appears to be a pathomechanism which occurs early in the course of many different neurodegenerative disorders. Among the most well-known of these protein aggregations are the amyloid-plaques, which arise from the aggregation of the {beta}-amyloid protein. Currently, this amyloid-aggregation pathology is regarded as a key pathology, playing a causal role in the development of AD. Consequently, modern therapy approaches are directed towards this target. Limited access to brain tissue has so far restricted the definite diagnosis of AD to post mortem histopathological assessment of brain tissue. For the same reason, a clear association between extent of amyloid deposition pathology and clinical course of AD has not been established so far. However, particularly with regard to new therapeutic options a reliable in vivo diagnosis is required. Modern molecular imaging tracers such as [{sup 11}C]PIB do now open the possibility to visualize amyloid-depositions in vivo, using Positron Emission Tomography (PET). These techniques allow the characterization of dementing disorders on the basis of the underlying pathology rather than on their symptomatic appearance. This type of ''in vivo histopathology''-approach may offer improved options for early and differential diagnosis, as well as for patient selection for therapy trials and for objective therapy monitoring. (orig.)

  13. Disrupting beta-amyloid aggregation for Alzheimer disease treatment.

    Science.gov (United States)

    Estrada, L D; Soto, C

    2007-01-01

    Alzheimer's disease is a devastating degenerative disorder for which there is no cure or effective treatment. Although the etiology of Alzheimer's disease is not fully understood, compelling evidence indicates that deposition of aggregates composed by a misfolded form of the amyloid beta peptide (Abeta) is the central event in the disease pathogenesis. Therefore, an attractive therapeutic strategy is to prevent or reverse Abeta misfolding and aggregation. Diverse strategies have been described to identify inhibitors of this process, including screening of libraries of small molecules chemical compounds, rational design of synthetic peptides, assessment of natural Abeta-binding proteins and stimulation of the immune system by vaccination. In this article we describe these different approaches, their principles and their potential strengths and weaknesses. Overall the available data suggest that the development of drugs to interfere with Abeta misfolding and aggregation is a feasible target that hold great promise for the treatment of Alzheimer's disease.

  14. Adherence to the Mediterranean Diet Is not Related to Beta-Amyloid Deposition: Data from the Women's Healthy Ageing Project.

    Science.gov (United States)

    Hill, E; Szoeke, C; Dennerstein, L; Campbell, S; Clifton, P

    2018-01-01

    Research has indicated the neuroprotective potential of the Mediterranean diet. Adherence to the Mediterranean diet has shown preventative potential for Alzheimer's disease incidence and prevalence, yet few studies have investigated the impact of Mediterranean diet adherence on the hallmark protein; beta-amyloid. To investigate the association between Mediterranean diet adherence and beta-amyloid deposition in a cohort of healthy older Australian women. This study was a cross-sectional investigation of participants from the longitudinal, epidemiologically sourced Women's Healthy Ageing Project which is a follow-up of the Melbourne Women's Midlife Health Project. Assessments were conducted at the Centre for Medical Research, Royal Melbourne Hospital in Melbourne, Australia. F-18 Florbetaben positron emission tomography scanning was conducted at the Austin Centre for PET in Victoria, Australia. One hundred and eleven Women's Healthy Ageing Project participants were included in the study. Mediterranean diet adherence scores for all participants were calculated from the administration of a validated food frequency questionnaire constructed by the Cancer Council of Victoria. Beta-amyloid deposition was measured using positron emission tomography standardised uptake value ratios. Gamma regression analysis displayed no association between Mediterranean diet adherence and beta-amyloid deposition. This result was consistent across APOE-ε4 +/- cohorts and with the inclusion of covariates such as age, education, body mass index and cognition. This study found no association between adherence to the Mediterranean diet and beta-amyloid deposition in a cohort of healthy Australian women.

  15. Regional brain hypometabolism is unrelated to regional amyloid plaque burden.

    Science.gov (United States)

    Altmann, Andre; Ng, Bernard; Landau, Susan M; Jagust, William J; Greicius, Michael D

    2015-12-01

    In its original form, the amyloid cascade hypothesis of Alzheimer's disease holds that fibrillar deposits of amyloid are an early, driving force in pathological events leading ultimately to neuronal death. Early clinicopathological investigations highlighted a number of inconsistencies leading to an updated hypothesis in which amyloid plaques give way to amyloid oligomers as the driving force in pathogenesis. Rather than focusing on the inconsistencies, amyloid imaging studies have tended to highlight the overlap between regions that show early amyloid plaque signal on positron emission tomography and that also happen to be affected early in Alzheimer's disease. Recent imaging studies investigating the regional dependency between metabolism and amyloid plaque deposition have arrived at conflicting results, with some showing regional associations and other not. We extracted multimodal neuroimaging data from the Alzheimer's disease neuroimaging database for 227 healthy controls and 434 subjects with mild cognitive impairment. We analysed regional patterns of amyloid deposition, regional glucose metabolism and regional atrophy using florbetapir ((18)F) positron emission tomography, (18)F-fluordeoxyglucose positron emission tomography and T1-weighted magnetic resonance imaging, respectively. Specifically, we derived grey matter density and standardized uptake value ratios for both positron emission tomography tracers in 404 functionally defined regions of interest. We examined the relation between regional glucose metabolism and amyloid plaques using linear models. For each region of interest, correcting for regional grey matter density, age, education and disease status, we tested the association of regional glucose metabolism with (i) cortex-wide florbetapir uptake; (ii) regional (i.e. in the same region of interest) florbetapir uptake; and (iii) regional florbetapir uptake while correcting in addition for cortex-wide florbetapir uptake. P-values for each setting

  16. Amyloid cascade in Alzheimer's disease: Recent advances in medicinal chemistry.

    Science.gov (United States)

    Mohamed, Tarek; Shakeri, Arash; Rao, Praveen P N

    2016-05-04

    Alzheimer's disease is of major concern all over the world due to a number of factors including (i) an aging population (ii) increasing life span and (iii) lack of effective pharmacotherapy options. The past decade has seen intense research in discovering disease-modifying multitargeting small molecules as therapeutic options. The pathophysiology of Alzheimer's disease is attributed to a number of factors such as the cholinergic dysfunction, amyloid/tau toxicity and oxidative stress/mitochondrial dysfunction. In recent years, targeting the amyloid cascade has emerged as an attractive strategy to discover novel neurotherapeutics. Formation of beta-amyloid species, with different degrees of solubility and neurotoxicity is associated with the gradual decline in cognition leading to dementia. The two commonly used approaches to prevent beta-amyloid accumulation in the brain include (i) development of beta-secretase inhibitors and (ii) designing direct inhibitors of beta-amyloid (self-induced) aggregation. This review highlights the amyloid cascade hypothesis and the key chemical features required to design small molecules that inhibit lower and higher order beta-amyloid aggregates. Several recent examples of small synthetic molecules with disease-modifying properties were considered and their molecular docking studies were conducted using either a dimer or steric-zipper assembly of beta-amyloid. These investigations provide a mechanistic understanding on the structural requirements needed to design novel small molecules with anti-amyloid aggregation properties. Significantly, this work also demonstrates that the structural requirements to prevent aggregation of various amyloid species differs considerably, which explains the fact that many small molecules do not exhibit similar inhibition profile toward diverse amyloid species such as dimers, trimers, tetramers, oligomers, protofibrils and fibrils. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Rapidly progressive polyneuropathy due to dry beriberi in a man: a case report

    Directory of Open Access Journals (Sweden)

    Lekwuwa Godwin

    2010-12-01

    Full Text Available Abstract Introduction We describe a case of rapidly progressive and severely debilitating polyneuropathy in a patient with confirmed hypovitaminosis B1, consistent with dry beriberi. Crucially, this is a treatable condition, although sometimes with incomplete recovery, but it is probably under-recognized yet increasingly common given increasing levels of alcohol abuse in the western world. Case presentation A 49-year-old Caucasian British man presented with progressive weakness of both lower limbs of approximately seven months' duration. He noted difficulty climbing stairs. He also complained of lethargy, and loss of muscle bulk, including his thighs. He had a history of type 2 diabetes mellitus and admitted prior alcohol abuse but denied excessive alcohol intake in the five years prior to presentation. Initial clinical and neurophysiological examinations were consistent with a mild peripheral neuropathy and probable proximal myopathy. However, over the subsequent four months he evolved a marked tetraparesis, with profound sensory disturbance of all limbs. Repeat neurophysiology revealed a widespread polyneuropathy with extensive acute and sub-acute denervation changes in all four limbs, and reduced or absent sensory nerve action potentials. Hypovitaminosis B1 was confirmed (45 nmol/L, reference range 66-200 nmol/L. His rapid clinical deterioration was in keeping with dry beriberi. He was treated with thiamine. Subsequent follow-up revealed slow but significant improvement, such that by 15-16 months from the initial onset of symptoms, and approximately six months after the onset of his marked tetraparesis, he was able to stand independently and was gradually gaining confidence in walking pending a period of in-patient neurorehabilitation. Conclusion A potentially wide differential diagnosis exists for this type of presentation. Confirming hypovitaminosis B1 by requesting the assay prior to vitamin replacement ensures accurate diagnosis and

  18. The Pattern of Brain Amyloid Load in Posterior Cortical Atrophy Using 18F-AV45: Is Amyloid the Principal Actor in the Disease

    Directory of Open Access Journals (Sweden)

    Emilie Beaufils

    2014-11-01

    Full Text Available Background: Posterior cortical atrophy (PCA is characterized by progressive higher-order visuoperceptual dysfunction and praxis declines. This syndrome is related to a number of underlying diseases, including, in most cases, Alzheimer's disease (AD. The aim of this study was to compare the amyloid load with 18F-AV45 positron emission tomography (PET between PCA and AD subjects. Methods: We performed 18F-AV45 PET, cerebrospinal fluid (CSF biomarker analysis and a neuropsychological assessment in 11 PCA patients and 12 AD patients. Results: The global and regional 18F-AV45 uptake was similar in the PCA and AD groups. No significant correlation was observed between global 18F-AV45 uptake and CSF biomarkers or between regional 18F-AV45 uptake and cognitive and affective symptoms. Conclusion: This 18F-AV45 PET amyloid imaging study showed no specific regional pattern of cortical 18F-AV45 binding in PCA patients. These results confirm that a distinct clinical phenotype in amnestic AD and PCA is not related to amyloid distribution.

  19. The Pattern of Brain Amyloid Load in Posterior Cortical Atrophy Using (18)F-AV45: Is Amyloid the Principal Actor in the Disease?

    Science.gov (United States)

    Beaufils, Emilie; Ribeiro, Maria Joao; Vierron, Emilie; Vercouillie, Johnny; Dufour-Rainfray, Diane; Cottier, Jean-Philippe; Camus, Vincent; Mondon, Karl; Guilloteau, Denis; Hommet, Caroline

    2014-09-01

    Posterior cortical atrophy (PCA) is characterized by progressive higher-order visuoperceptual dysfunction and praxis declines. This syndrome is related to a number of underlying diseases, including, in most cases, Alzheimer's disease (AD). The aim of this study was to compare the amyloid load with (18)F-AV45 positron emission tomography (PET) between PCA and AD subjects. We performed (18)F-AV45 PET, cerebrospinal fluid (CSF) biomarker analysis and a neuropsychological assessment in 11 PCA patients and 12 AD patients. The global and regional (18)F-AV45 uptake was similar in the PCA and AD groups. No significant correlation was observed between global (18)F-AV45 uptake and CSF biomarkers or between regional (18)F-AV45 uptake and cognitive and affective symptoms. This (18)F-AV45 PET amyloid imaging study showed no specific regional pattern of cortical (18)F-AV45 binding in PCA patients. These results confirm that a distinct clinical phenotype in amnestic AD and PCA is not related to amyloid distribution.

  20. Memory Impairment in Estrogen Receptor ? Knockout Mice Through Accumulation of Amyloid-? Peptides

    OpenAIRE

    Hwang, Chul Ju; Yun, Hyung-Mun; Park, Kyung-Ran; Song, Ju Kyung; Seo, Hyun Ok; Hyun, Byung Kook; Choi, Dong Young; Yoo, Hwan-Soo; Oh, Ki-Wan; Hwang, Dae Yeun; Han, Sang-Bae; Hong, Jin Tae

    2014-01-01

    Estrogen has been known to reduce the development of Alzheimer?s disease (AD). However, exact mechanisms are not clear. We investigated whether estrogen can increase amyloid-beta (A?) degradation and affects A?-induced memory impairment in an estrogen deficiency model. Estrogen receptor alpha (ER?) knockout mice and wild-type mice were intracerebroventricular (ICV) infused with A? (300?pmol) for 2?weeks. Cognitive function was then assessed by the Morris water maze test and passive avoidance ...

  1. Protective Effects of Indian Spice Curcumin Against Amyloid Beta in Alzheimer’s Disease

    OpenAIRE

    Reddy, P. Hemachandra; Manczak, Maria; Yin, Xiangling; Grady, Mary Catherine; Mitchell, Andrew; Tonk, Sahil; Kuruva, Chandra Sekhar; Bhatti, Jasvinder Singh; Kandimalla, Ramesh; Vijayan, Murali; Kumar, Subodh; Wang, Rui; Adi Pradeepkiran, Jangampalli; Ogunmokun, Gilbert; Thamarai, Kavya

    2018-01-01

    The purpose of our article is to assess the current understanding of Indian spice ‘Curcumin’ against amyloid-β (Aβ)-induced toxicity in Alzheimer’s disease (AD) pathogenesis. Natural products, such as ginger, curcumin and gingko biloba have been used as diets and dietary supplements to treat human diseases, including cancer, cardiovascular, respiratory, infectious, diabetes, obesity, metabolic syndromes and neurological disorders. Products derived from plants are known to have protective effe...

  2. A Peptide-Fc Opsonin with Pan-Amyloid Reactivity

    Directory of Open Access Journals (Sweden)

    James S. Foster

    2017-09-01

    Full Text Available There is a continuing need for therapeutic interventions for patients with the protein misfolding disorders that result in systemic amyloidosis. Recently, specific antibodies have been employed to treat AL amyloidosis by opsonizing tissue amyloid deposits thereby inducing cell-mediated dissolution and organ improvement. To develop a pan-amyloid therapeutic agent, we have produced an Fc-fusion product incorporating a peptide, p5, which binds many if not all forms of amyloid. This protein, designated Fcp5, expressed in mammalian cells, forms the desired bivalent dimer structure and retains pan-amyloid reactivity similar to the p5 peptide as measured by immunosorbent assays, immunohistochemistry, surface plasmon resonance, and pulldown assays using radioiodinated Fcp5. Additionally, Fcp5 was capable of opsonizing amyloid fibrils in vitro using a pH-sensitive fluorescence assay of phagocytosis. In mice,125 I-labeled Fcp5 exhibited an extended serum circulation time, relative to the p5 peptide. It specifically bound AA amyloid deposits in diseased mice, as evidenced by biodistribution and microautoradiographic methods, which coincided with an increase in active, Iba-1-positive macrophages in the liver at 48 h postinjection of Fcp5. In healthy mice, no specific tissue accumulation was observed. The data indicate that polybasic, pan-amyloid-targeting peptides, in the context of an Fc fusion, can yield amyloid reactive, opsonizing reagents that may serve as next-generation immunotherapeutics.

  3. Native human serum amyloid P component is a single pentamer

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH

    1995-01-01

    Serum amyloid P component (SAP) and C-reactive protein (CRP) are members of the pentraxin protein family. SAP is the precursor protein to amyloid P component present in all forms of amyloidosis. The prevailing notion is that SAP in circulation has the form of a double pentameric molecule (decamer...

  4. Beyond Amyloid - Widening the View on Alzheimer's Disease.

    Science.gov (United States)

    Behl, Christian; Ziegler, Christine

    2017-11-01

    For 25 years, the amyloid cascade hypothesis, based on the finding that mutations in the amyloid precursor protein are closely linked to familial forms of Alzheimer's disease (AD), dominated the research on this disease. Recent failures of clinical anti-amyloidogenic trials, however, substantially support the reasoning (i) that the pathomechanisms that trigger familial AD, namely the generation, aggregation, and deposition of amyloid beta, cannot necessarily be extrapolated to sporadic cases and (ii) that amyloid beta represents a prominent histopathological feature in AD but not its exclusive causative factor. In autumn 2016, the Volkswagen Foundation hosted the Herrenhausen Symposium 'Beyond Amyloid - Widening the View on Alzheimer's Disease' in Hannover, Germany, to bring together current knowledge on cellular and molecular processes that contribute to AD pathogenesis independent of or alongside with the amyloid biochemistry. The following mini review series was authored by key speakers at the meeting, and highlights some of the mechanisms potentially involved in AD etiology that provide alternative viewpoints and mechanisms beyond the amyloid cascade hypothesis. This article is part of the series "Beyond Amyloid". © 2017 International Society for Neurochemistry.

  5. Amyloid goitre following chronic osteomyelitis: case report and ...

    African Journals Online (AJOL)

    Amyloid goitre following chronic osteomyelitis: case report and review of literature. AZ Mohammed, ST Edino, O Ochicha. Abstract. Amyloid Goitre is a rare clinical entity associated with systemic amyloidosis. It poses a significant diagnostic and therapeutic challenge and may be confused with a neoplastic goiter. We present ...

  6. Effects of diet-induced hypercholesterolemia on amyloid ...

    Indian Academy of Sciences (India)

    2012-10-27

    Oct 27, 2012 ... To test the above hypothesis, we used ovariectomized with diet-induced hypercholesterolemia (OVX) and hypercholesterolemia (HCL) diet alone mouse models. HPLC analysis reveals the presence of beta amyloid in the OVX and HCL mice brain. Congo red staining analysis revealed the extent of amyloid ...

  7. Collapsed state of polyglutamic acid results in amyloid spherulite formation

    Science.gov (United States)

    Stehli, Daniel; Mulaj, Mentor; Miti, Tatiana; Traina, Joshua; Foley, Joseph; Muschol, Martin

    2015-01-01

    Self-assembly of proteins and peptides into amyloid fibrils involves multiple distinct intermediates and late-stage fibrillar polymorphs. Understanding the conditions and mechanisms that promote the formation of one type of intermediate and polymorph over the other represents a fundamental challenge. Answers to this question are also of immediate biomedical relevance since different amyloid aggregate species have been shown to have distinct pathogenic potencies. One amyloid polymorph that has received comparatively little attention are amyloid spherulites. Here we report that self-assembly of the intrinsically disordered polymer poly(L-glutamic) acid (PLE) can generate amyloid spherulites. We characterize spherulite growth kinetics, as well as the morphological, optical and tinctorial features of this amyloid polymorph previously unreported for PLE. We find that PLE spherulites share both tinctorial and structural characteristics with their amyloid fibril counterparts. Differences in PLE's molecular weight, polydispersity or chemistry could not explain the selective propensity toward either fibril or spherulite formation. Instead, we provide evidence that PLE polymers can exist in either a collapsed globule or an extended random coil conformation. The collapsed globule consistently produces spherulites while the extended coil assembles into disordered fibril bundles. This results suggests that these 2 PLE conformers directly affect the morphology of the resulting macroscopic amyloid assembly. PMID:28232889

  8. Prevalence of amyloid PET positivity in dementia syndromes

    DEFF Research Database (Denmark)

    Ossenkoppele, Rik; Jansen, Willemijn J; Rabinovici, Gil D

    2015-01-01

    IMPORTANCE: Amyloid-β positron emission tomography (PET) imaging allows in vivo detection of fibrillar plaques, a core neuropathological feature of Alzheimer disease (AD). Its diagnostic utility is still unclear because amyloid plaques also occur in patients with non-AD dementia. OBJECTIVE: To us...

  9. Specific Triazine Herbicides Induce Amyloid-beta(42) Production

    NARCIS (Netherlands)

    Portelius, Erik; Durieu, Emilie; Bodin, Marion; Cam, Morgane; Pannee, Josef; Leuxe, Charlotte; Mabondzo, Aloise; Oumata, Nassima; Galons, Herve; Lee, Jung Yeol; Chang, Young-Tae; Stuber, Kathrin; Koch, Philipp; Fontaine, Gaelle; Potier, Marie-Claude; Manousopoulou, Antigoni; Garbis, Spiros D.; Covaci, Adrian; Van Dam, Debby; De Deyn, Peter; Karg, Frank; Flajolet, Marc; Omori, Chiori; Hata, Saori; Suzuki, Toshiharu; Blennow, Kaj; Zetterberg, Henrik; Meijer, Laurent

    2016-01-01

    Proteolytic cleavage of the amyloid-beta protein precursor (A beta PP) ecretases leads to extracellular release of amyloid-beta (A beta) peptides. Increased production of A beta(42) over A beta(40) and aggregation into oligomers and plaques constitute an Alzheimer's disease (AD) hallmark.

  10. Ligand-binding sites in human serum amyloid P component

    DEFF Research Database (Denmark)

    Heegaard, N.H.H.; Heegaard, Peter M. H.; Roepstorff, P.

    1996-01-01

    Amyloid P component (AP) is a naturally occurring glycoprotein that is found in serum and basement membranes, AP is also a component of all types of amyloid, including that found in individuals who suffer from Alzheimer's disease and Down's syndrome. Because AP has been found to bind strongly...

  11. The effect of amyloid pathology and glucose metabolism on cortical volume loss over time in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Adriaanse, Sofie M. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); VU University Medical Center, Department of Radiology and Nuclear Medicine, Alzheimer Center, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Van Dijk, Koene R.A. [Harvard University, Department of Psychology, Center for Brain Science, Cambridge, MA (United States); Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Ossenkoppele, Rik; Tolboom, Nelleke; Zwan, Marissa D.; Barkhof, Frederik; Berckel, Bart N.M. van [VU University Medical Center, Department of Radiology and Nuclear Medicine, Alzheimer Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Reuter, Martin [Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA (United States); Massachusetts Institute of Technology, Computer Science and Artificial Intelligence Laboratory, Division of Health Sciences and Technology, Cambridge, MA (United States); Yaqub, Maqsood; Boellaard, Ronald; Windhorst, Albert D.; Lammertsma, Adriaan A. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Flier, Wiesje M. van der; Scheltens, Philip [VU University Medical Center, Department of Neurology, Alzheimer Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands)

    2014-06-15

    The present multimodal neuroimaging study examined whether amyloid pathology and glucose metabolism are related to cortical volume loss over time in Alzheimer's disease (AD) patients and healthy elderly controls. Structural MRI scans of eleven AD patients and ten controls were available at baseline and follow-up (mean interval 2.5 years). Change in brain structure over time was defined as percent change of cortical volume within seven a-priori defined regions that typically show the strongest structural loss in AD. In addition, two PET scans were performed at baseline: [{sup 11}C]PIB to assess amyloid-β plaque load and [{sup 18}F]FDG to assess glucose metabolism. [{sup 11}C]PIB binding and [{sup 18}F]FDG uptake were measured in the precuneus, a region in which both amyloid deposition and glucose hypometabolism occur early in the course of AD. While amyloid-β plaque load at baseline was not related to cortical volume loss over time in either group, glucose metabolism within the group of AD patients was significantly related to volume loss over time (rho = 0.56, p < 0.05). The present study shows that in a group of AD patients amyloid-β plaque load as measured by [{sup 11}C]PIB behaves as a trait marker (i.e., all AD patients showed elevated levels of amyloid, not related to subsequent disease course), whilst hypometabolism as measured by [{sup 18}F]FDG changed over time indicating that it could serve as a state marker that is predictive of neurodegeneration. (orig.)

  12. Ulnar sensory-motor amplitude ratio: a new tool to differentiate ganglionopathy from polyneuropathy

    Directory of Open Access Journals (Sweden)

    Raphael Ubirajara Garcia

    2013-07-01

    Full Text Available The objective of this study was to evaluate if the ratio of ulnar sensory nerve action potential (SNAP over compound muscle action potential (CMAP amplitudes (USMAR would help in the distinction between ganglionopathy (GNP and polyneuropathy (PNP. Methods We reviewed the nerve conductions studies and electromyography (EMG of 18 GNP patients, 33 diabetic PNP patients and 56 controls. GNP was defined by simultaneous nerve conduction studies (NCS and magnetic resonance imaging (MRI abnormalities. PNP was defined by usual clinical and NCS criteria. We used ANOVA with post-hoc Tukey test and ROC curve analysis to compare ulnar SNAP and CMAP, as well as USMAR in the groups. Results Ulnar CMAP amplitudes were similar between GNP x PNP x Controls (p=0.253, but ulnar SNAP amplitudes (1.6±3.2 x 11.9±9.1 × 45.7±24.7 and USMAR values (0.3±0.3 × 1.5±0.9 × 4.6±2.2 were significantly different. A USMAR threshold of 0.71 was able to differentiate GNP and PNP (94.4% sensitivity and 90.9% specificity. Conclusions USMAR is a practical and reliable tool for the differentiation between GNP and PNP.

  13. Exploring a new therapy for diabetic polyneuropathy –the application of stem cell transplantation-

    Directory of Open Access Journals (Sweden)

    Hiroki eMizukami

    2014-04-01

    Full Text Available Diabetic polyneuropathy (DPN is the most common complication that emerges early in diabetic patients. Intervention with strict blood glucose control or treatment with aldose reductase inhibitor is reported to be effective in early stages of DPN. Curative treatment for overt or symptomatic DPN, however, has not been established, thus requiring much effort to explore a new therapy. Recent preclinical studies on the use of gene or cell therapy have provided promising results in the treatment of DPN. Of particular interest, induced pluripotent stem (iPS cells are introduced. In these studies, restoration of DPN was proposed to be attributed to either neurotrophic factors released from transplanted stem cells or differentiation of stem cells to substitute the damaged peripheral nerve. There are still several problems, however, that remain to be overcome, such as perturbed function, fragility or limited survival of transplanted cells in diabetes milieu and risk for malignant transformation of transplanted cells. Questions, which cell is the most appropriate as the source for cell therapy, or which site is the best for transplantation to obtain the most effective results, remain to be answered. In this communication, we overview the current status of preclinical studies on the cell therapy for DPN and discuss the future prospect.

  14. Comparison of electrodiagnostic abnormalities and criteria in a cohort of patients with chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Magda, Paul; Latov, Norman; Brannagan, Thomas H; Weimer, Louis H; Chin, Russell L; Sander, Howard W

    2003-12-01

    Current electrodiagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP) are research oriented favoring specificity over sensitivity. Application of such criteria in clinical practice may miss the diagnosis in potentially treatable patients. To analyze the electrophysiologic abnormalities in a cohort of patients with clinically defined CIDP, to compare these data with published electrodiagnostic criteria, and to identify a set of abnormalities that is shared by all patients with CIDP. Retrospective medical record review. Academically based neuromuscular clinic. Patients Fifteen patients with clinically diagnosed relapsing sensorimotor CIDP. Administration of intravenous immunoglobulin or prednisone. Electrodiagnostic studies. All patients had electrodiagnostic abnormalities in at least 3 nerves with possible partial conduction block or demyelinating range abnormalities in at least 1 nerve. The diagnostic sensitivities of 5 published CIDP criteria were as follows: the Ad Hoc Subcommittee of the American Academy of Neurology AIDS Task Force (40%), Saperstein et al (47%), Nicolas et al (53%), Hughes et al for the Inflammatory Neuropathy Cause and Treatment Group (60%), and Thaisetthawatkul et al (70%). Current electrodiagnostic criteria for CIDP are insensitive and may fail to diagnose the condition in a substantial number of patients. More inclusive criteria that allow identification of patients in routine clinical practice are needed.

  15. [Total antioxidant blood capacity in patients with type 2 diabetes mellitus and distal symmetrical polyneuropathy].

    Science.gov (United States)

    Dordević, Gordana; Durić, Stojanka; Apostolskit, Slobodan; Dordević, Vidosava; Zivković, Miroslava

    2008-09-01

    Reduced systemic antioxidant defence is considerd to play an important mediating role in pathogenesis of diabetic neuropathy. The aim of this study was to evaluate if the total antioxidant blood capacity (TAC) is reduced in patients with type 2 diabetes mellitus (DM) and diabetic distal symmetrical polyneuropathy (DDSP) and to correlate this antioxidant capacity with the degree of peripheral nerve dysfunction. This study involved 100 patients with type 2 DM and signs of DDSP, as well as the control group of 50 healthy subjects. The evaluation of DDSP was based on physical examination and nerve conduction studies. The degree of peripheral nerve dysfunction was estimated by scoring and analysing sensory and motor nerve conduction parameters (distal latency and amplitude of evoked potential, conduction velocity). Laboratory analyses involved blood glucose and HbA1C levels, as well as plasma TAC. Blood glucose and HbA1C level was significantly higher in the patients than in the control group (p diabetic group and the depletion was statistically significant (p nerve conduction parameters. Total antioxidant blood capacity is reduced in patients with DDSP, but it does not correlate with blood sugar level, with the duration of DM or with the degree of functional nerve damage. These results show a reduced systemic antioxidant defence in patients with type 2 DM and DDSP. However, it is still unclear to what extent the oxidative stress is a contributing factor or leading cause of diabetic neuropathy, suggesting that further studies are necessary.

  16. Elevated leukocyte count in cerebrospinal fluid of patients with chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Lucke, Ilse M; Peric, Stojan; van Lieverloo, Gwen G A; Wieske, Luuk; Verhamme, Camiel; van Schaik, Ivo N; Basta, Ivana; Eftimov, Filip

    2018-01-17

    Cerebrospinal fluid (CSF) examination is often part of the diagnostic work-up of a patient suspected of having chronic inflammatory demyelinating polyneuropathy (CIDP). According to the European Federation of Neurological Societies and the Peripheral Nerve Society (EFNS/PNS) criteria, an elevated protein level without pleocytosis (leukocytes leukocytes are compatible with the diagnosis CIDP and how extensive the diagnostic work-up should be in patients with a demyelinating neuropathy and pleocytosis. We performed a retrospective study at two tertiary neuromuscular referral clinics and identified 14 out of 273 (6%) patients with CIDP with elevated CSF leukocytes (≥10 cells/µl). All these patients met the EFNS/PNS criteria for definite or probable CIDP. Eight patients (57%) presented with a subacute onset and four patients with an antecedent infection. Most patients responded well to therapy, and eight patients are currently in remission. In four patients, lumbar puncture was repeated. A spontaneous decrease in leukocytes before start of treatment was found in three patients. Our data indicate that a mild to moderate pleocytosis in CSF does not exclude the diagnosis of CIDP, especially in patients with a subacute onset of disease. © 2018 Peripheral Nerve Society.

  17. Quantitative muscle ultrasound is useful for evaluating secondary axonal degeneration in chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Hokkoku, Keiichi; Matsukura, Kiyoshi; Uchida, Yudai; Kuwabara, Midori; Furukawa, Yuichi; Tsukamoto, Hiroshi; Hatanaka, Yuki; Sonoo, Masahiro

    2017-10-01

    In chronic inflammatory demyelinating polyneuropathy (CIDP), exclusion of secondary axonal degeneration is challenging with conventional methods such as nerve conduction study (NCS), needle electromyography, and nerve biopsy. Increased echo intensity (EI) and decreased muscle thickness (MT) identified on muscle ultrasound (MUS) examination represent muscle denervation due to axonal degeneration in neurogenic disorders, suggesting MUS as a new tool to detect secondary axonal degeneration in patients with CIDP. EI and MT of abductor pollicis brevis, abductor digiti minimi, and first dorsal interosseous muscles were measured in 16 CIDP patients. Raw values were converted into z -scores using data from 60 normal controls (NCs). Six of 45 muscles showed abnormally high EI and low MT, suggesting denervation following secondary axonal degeneration. These six muscles belonged to two patients with long disease history, unresponsiveness to treatment, and long interval from onset to initial therapy. There were no significant differences in EI and MT ( p  = .23 and .67, respectively) between the CIDP and NC groups, although NCS results revealed obvious demyelinating abnormalities in all CIDP patients, suggesting the fact that muscle structures will be preserved, and EI and MT will not change unless secondary axonal degeneration occurs in CIDP. MUS is a promising tool for evaluating secondary axonal degeneration in patients with CIDP.

  18. Isoniazid-induced polyneuropathy in a tuberculosis patient - implication for individual risk stratification with genotyping?

    Science.gov (United States)

    Stettner, Mark; Steinberger, Daniela; Hartmann, Christian J; Pabst, Tatjana; Konta, Lidija; Hartung, Hans Peter; Kieseier, Bernd C

    2015-08-01

    Development of polyneuropathy (PNP) under treatment for tuberculosis (TB), including isoniazid (INH), is a highly relevant adverse drug effect. The NAT2 acetylation status is a predictor of potential toxic effects of INH. The question as to whether individual risk stratification by genotyping is useful to avoid suffering of patients and to lower costs for the health care system is of considerable clinical importance. After drug treatment for TB, including INH, a 23-year-old man developed severe PNP. During the treatment, laboratory results have been indicating incipient liver and renal injury. Later, molecular genetic analyses were performed and revealed a variation in the NAT2 gene and the c1/c2 genotype of the CYP2E1 gene, both described to contribute to an elevated risk for anti-tuberculostatic-induced liver damages (ATIL). The combination of metabolizer genotypes should be taken into account as a cause for toxic effects and the development of PNP. Individual genotyping, performed before medication or at least if an elevation of liver parameters is observed, may reduce the risk of severe cases of PNP by early adjustment of treatment. Our case study indicates that evaluation of individual risk stratification with systematic pharmacogenetic genotyping of metabolizer gene combinations in the context of TB treatment should be addressed in clinical studies with larger cohorts.

  19. Critical illness myopathy and polyneuropathy - A challenge for physiotherapists in the intensive care units

    Science.gov (United States)

    Pattanshetty, Renu B.; Gaude, Gajanan S.

    2011-01-01

    The development of critical patient related generalized neuromuscular weakness, referred to as critical illness polyneuropathy (CIP) and critical illness myopathy (CIM), is a major complication in patients admitted to intensive care units (ICU). Both CIP and CIM cause muscle weakness and paresis in critically ill patients during their ICU stay. Early mobilization or kinesiotherapy have shown muscle weakness reversion in critically ill patients providing faster return to function, reducing weaning time, and length of hospitalization. Exercises in the form of passive, active, and resisted forms have proved to improve strength and psychological well being. Clinical trials using neuromuscular electrical stimulation to increase muscle mass, muscle strength and improve blood circulation to the surrounding tissue have proved beneficial. The role of electrical stimulation is unproven as yet. Recent evidence indicates no difference between treated and untreated muscles. Future research is recommended to conduct clinical trials using neuromuscular electrical stimulation, exercises, and early mobilization as a treatment protocol in larger populations of patients in ICU. PMID:21814370

  20. Treatment of critical illness polyneuropathy and/or myopathy - a systematic review.

    Science.gov (United States)

    Ydemann, Mogens; Eddelien, Heidi Shil; Lauritsen, Anne Øberg

    2012-10-01

    The objective was to search the literature with a view to providing a general description of critical illness myopathy/polyneuropathy (CIM/CIP), including its genesis and prevention. Furthermore, it was our aim to determine whether new treatments have occurred in the past five years. PubMed, Cinahl and Swedmed+ were searched using the terms CIM, CIP and intensive care. The search was narrowed by adding the limits: humans, English, Danish, Norwegian, Swedish and, furthermore, articles had to have been published in the past five years as we aimed to focus on new knowledge. A total of 74 articles were found. We excluded articles focusing on children and intensive care, tight insulin therapy in patients without CIM/CIP and articles focusing on Guillain-Barré syndrome, triage, bleeding, alcohol or meningitis. Of the remaining 36 articles, only five focused on CIM/CIP treatment. Their relevant original references were found and used too. CIM/CIP is the most commonly occurring intensive care unit (ICU)-acquired neuromuscular dysfunction, and it is associated with a significant increase in length of stay, delayed weaning from mechanical ventilation, prolonged rehabilitation and, consequently, more expenses. To treat/prevent this condition, it seems reasonable to ensure maximal functional status for survivors of an ICU-stay by applying a multimodal therapeutic approach that includes intensive insulin therapy, minimal sedation and, as suggested by new evidence, early physiotherapy and electrical muscle stimulation.

  1. Standing postural reaction to visual and proprioceptive stimulation in chronic acquired demyelinating polyneuropathy

    Directory of Open Access Journals (Sweden)

    Clement P. Provost

    2018-01-01

    Full Text Available Objective: To investigate the weight of visual and proprioceptive inputs, measured indirectly in standing position control, in patients with chronic acquired demyelinating polyneuropathy (CADP. Design: Prospective case study. Subjects: Twenty-five patients with CADP and 25 healthy controls. Methods: Posture was recorded on a double force platform. Stimulations were optokinetic (60°/s for visual input and vibration (50 Hz for proprioceptive input. Visual stimulation involved 4 tests (upward, downward, rightward and leftward and proprioceptive stimulation 2 tests (triceps surae and tibialis anterior. A composite score, previously published and slightly modified, was used for the recorded postural signals from the different stimulations. Results: Despite their sensitivity deficits, patients with CADP were more sensitive to proprioceptive stimuli than were healthy controls (mean composite score 13.9 ((standard deviation; SD 4.8 vs 18.4 (SD 4.8, p = 0.002. As expected, they were also more sensitive to visual stimuli (mean composite score 10.5 (SD 8.7 vs 22.9 (SD 7.5, p< 0.0001. Conclusion: These results encourage balance rehabilitation of patients with CADP, aimed at promoting the use of proprioceptive information, thereby reducing too-early development of visual compensation while proprioception is still available.

  2. Cardio-Ankle Vascular Index and Indices of Diabetic Polyneuropathy in Patients with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Akihiko Ando

    2017-01-01

    Full Text Available The cardio-ankle vascular index (CAVI is used to test vascular function and is an arterial stiffness marker and potential predictor of cardiovascular events. This study aimed to analyze the relation between objective indices of diabetic polyneuropathy (DPN and the CAVI. One hundred sixty-six patients with type 2 diabetes mellitus were included in this study. We used nerve conduction studies (NCSs and the coefficient of variation of the R-R interval to evaluate DPN. We estimated arteriosclerosis by the CAVI. Simple and multiple linear regression analyses were performed between neuropathy indices and the CAVI. In univariate analysis, the CAVI showed significant associations with sural sensory nerve conduction velocity and median F-wave conduction velocity. Multiple linear regression analysis for the CAVI showed that sural nerve conduction velocity and median F-wave conduction velocity were significant explanatory variables second only to age. In multiple linear regression analysis for sural nerve conduction velocity among neuropathy indices, the CAVI remained the most significant explanatory variable. In multiple linear regression analysis for median nerve F-wave conduction velocity among neuropathy indices, the CAVI remained the second most significant explanatory variable following HbA1c. These results suggest a close relationship between macroangiopathy and DPN.

  3. Screening for amyloid in subcutaneous fat tissue of Egyptian patients with rheumatoid arthritis : clinical and laboratory characteristics

    NARCIS (Netherlands)

    El Mansoury, T.M.; Hazenberg, B. P. C.; Badawy, S. A. El; Ahmed, A.H.; Bijzet, J.; Limburg, P.C.; Van Rijswijk, M.H.

    Objective: To screen for amyloid and to assess associated clinical and laboratory characteristics in Egyptian patients with rheumatoid arthritis (RA). Methods: Abdominal subcutaneous fat aspirates were consecutively collected from 112 patients (103 women, nine men) having RA for five years or more.

  4. Conformational dynamics of amyloid proteins at the aqueous interface

    Science.gov (United States)

    Armbruster, Matthew; Horst, Nathan; Aoki, Brendy; Malik, Saad; Soto, Patricia

    2013-03-01

    Amyloid proteins is a class of proteins that exhibit distinct monomeric and oligomeric conformational states hallmark of deleterious neurological diseases for which there are not yet cures. Our goal is to examine the extent of which the aqueous/membrane interface modulates the folding energy landscape of amyloid proteins. To this end, we probe the dynamic conformational ensemble of amyloids (monomer prion protein and Alzheimer's Ab protofilaments) interacting with model bilayers. We will present the results of our coarse grain molecular modeling study in terms of the existence of preferential binding spots of the amyloid to the bilayer and the response of the bilayer to the interaction with the amyloid. NSF Nebraska EPSCoR First Award

  5. Inhibition of Toxic IAPP Amyloid by Extracts of Common Fruits.

    Science.gov (United States)

    Kao, Pei-Yu; Green, Evangeline; Pereira, Catalina; Ekimura, Shauna; Juarez, Dennis; Whyte, Travis; Arhar, Taylor; Malaspina, Bianca; Nogaj, Luiza A; Moffet, David A

    2015-01-01

    The aggregation of the 37-amino acid polypeptide islet amyloid polypeptide (IAPP, amylin), as either insoluble amyloid or as small oligomers, appears to play a direct role in the death of pancreatic β-islet cells in type 2 diabetes. It is believed that inhibiting the aggregation of IAPP may slow down, if not prevent entirely, the progression of this disease. Extracts of thirteen different common fruits were analyzed for their ability to prevent the aggregation of amyloidogenic IAPP. Thioflavin T binding, immuno-detection and circular dichroism assays were performed to test the in vitro inhibitory potential of each extract. Atomic force microscopy was used to visualize the formation of amyloid fibrils with and without each fruit extract. Finally, extracts were tested for their ability to protect living mammalian cells from the toxic effects of amyloid IAPP. Several fruits showed substantial ability to inhibit IAPP aggregation and protect living cells from toxic IAPP amyloid.

  6. Microbiosensor for Alzheimer's disease diagnostics: detection of amyloid beta biomarkers.

    Science.gov (United States)

    Prabhulkar, Shradha; Piatyszek, Rudolph; Cirrito, John R; Wu, Ze-Zhi; Li, Chen-Zhong

    2012-07-01

    Alzheimer's disease (AD) affects about 35.6 million people worldwide, and if current trends continue with no medical advancement, one in 85 people will be affected by 2050. Thus, there is an urgent need to develop a cost-effective, easy to use, sensor platform to diagnose and study AD. The measurement of peptide amyloid beta (Aβ) found in CSF has been assessed as an avenue to diagnose and study the disease. The quantification of the ratio of Aβ1-40/42 (or Aβ ratio) has been established as a reliable test to diagnose AD through human clinical trials. Therefore, we have developed a multiplexed, implantable immunosensor to detect amyloid beta (Aβ) isoforms using triple barrel carbon fiber microelectrodes as the sensor platform. Antibodies act as the biorecognition element of the sensor and selectively capture and bind Aβ1-40 and Aβ1-42 to the electrode surface. Electrochemistry was used to measure the intrinsic oxidation signal of Aβ at 0.65 V (vs. Ag/AgCl), originating from a single tyrosine residue found at position 10 in its amino acid sequence. Using the proposed immunosensor Aβ1-40 and Aβ1-42 could be specifically detected in CSF from mice within a detection range of 20-50 nM and 20-140 nM respectively. The immunosensor enables real-time, highly sensitive detection of Aβ and opens up the possibilities for diagnostic ex vivo applications and research-based in vivo studies. © 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry.

  7. Design and Construction of Large Amyloid Fibers

    OpenAIRE

    Ridgley, Devin M.; Rippner, Caitlin M. W.; Barone, Justin R.

    2015-01-01

    Mixtures of “template” and “adder” proteins self-assemble into large amyloid fibers of varying morphology and modulus. Fibers range from low modulus, rectangular cross-sectioned tapes to high modulus, circular cross-sectioned cylinders. Varying the proteins in the mixture can elicit “in-between” morphologies, such as elliptical cross-sectioned fibers and twisted tapes, both of which have moduli in-between rectangular tapes and cylindrical fibers. Experiments on mixtures of proteins of known a...

  8. Imaging of dialysis-related amyloid (AB-amyloid) deposits with 131I-beta 2-microglobulin

    International Nuclear Information System (INIS)

    Floege, J.; Burchert, W.; Brandis, A.; Gielow, P.; Nonnast-Daniel, B.; Spindler, E.; Hundeshagen, H.; Shaldon, S.; Koch, K.M.

    1990-01-01

    The diagnosis of dialysis-related amyloid (AB-amyloid) has been based usually on clinical and radiological criteria. Following the discovery that beta 2-microglobulin was the major protein of this amyloid, we isolated and radiolabelled uremic plasma beta 2-microglobulin. After intravenous injection, gamma-camera images of selected joint areas were obtained from 42 patients who were on regular hemodialysis therapy. Positive scans involving the shoulder, hip, knee and carpal regions were found in 13 of 14 patients treated for more than 10 years and 10 of 16 patients treated for 5 to 10 years. Patients treated for less time had negative scans. Specificity was indicated by negative scans in non-amyloid inflammatory lesions in control hemodialysis patients. Up to 48-fold tracer enrichment was detected in excised AB-amyloid containing tissue as compared to amyloid-free tissue. These findings suggest that circulating radiolabelled beta 2-microglobulin is taken up by the amyloid deposits. This method may non-invasively detect tissue infiltrates of amyloid. It may also permit prospective evaluation of the efficacy of prophylactic dialysis strategies which are designed to prevent or delay the onset of this complication of long-term dialysis

  9. Amyloid-related imaging abnormalities in amyloid-modifying therapeutic trials: Recommendations from the Alzheimer's Association Research Roundtable Workgroup

    NARCIS (Netherlands)

    Sperling, R.A.; Jack, C.R.; Black, S.E.; Frosch, M.P.; Greenberg, S.M.; Hyman, B.T.; Scheltens, P.; Carrillo, M.C.; Thies, W.; Bednar, M.M.; Black, R.S.; Brashear, H.R.; Grundman, M.; Siemers, E.R.; Feldman, H.H.; Schindler, R.J.

    2011-01-01

    Amyloid imaging related abnormalities (ARIA) have now been reported in clinical trials with multiple therapeutic avenues to lower amyloid-β burden in Alzheimer's disease (AD). In response to concerns raised by the Food and Drug Administration, the Alzheimer's Association Research Roundtable convened

  10. Animal models of cerebral amyloid angiopathy.

    Science.gov (United States)

    Jäkel, Lieke; Van Nostrand, William E; Nicoll, James A R; Werring, David J; Verbeek, Marcel M

    2017-10-15

    Cerebral amyloid angiopathy (CAA), due to vascular amyloid β (Aβ) deposition, is a risk factor for intracerebral haemorrhage and dementia. CAA can occur in sporadic or rare hereditary forms, and is almost invariably associated with Alzheimer's disease (AD). Experimental (animal) models are of great interest in studying mechanisms and potential treatments for CAA. Naturally occurring animal models of CAA exist, including cats, dogs and non-human primates, which can be used for longitudinal studies. However, due to ethical considerations and low throughput of these models, other animal models are more favourable for research. In the past two decades, a variety of transgenic mouse models expressing the human Aβ precursor protein (APP) has been developed. Many of these mouse models develop CAA in addition to senile plaques, whereas some of these models were generated specifically to study CAA. In addition, other animal models make use of a second stimulus, such as hypoperfusion or hyperhomocysteinemia (HHcy), to accelerate CAA. In this manuscript, we provide a comprehensive review of existing animal models for CAA, which can aid in understanding the pathophysiology of CAA and explore the response to potential therapies. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  11. Human serum amyloid genes--molecular characterization

    International Nuclear Information System (INIS)

    Sack, G.H.; Lease, J.J.

    1986-01-01

    Three clones containing human genes for serum amyloid A protein (SAA) have been isolated and characterized. Each of two clones, GSAA 1 and 2 (of 12.8 and 15.9 kilobases, respectively), contains two exons, accouting for amino acids 12-58 and 58-103 of mature SAA; the extreme 5' termini and 5' untranslated regions have not yet been defined but are anticipated to be close based on studies of murine SAA genes. Initial amino acid sequence comparisons show 78/89 identical residues. At 4 of the 11 discrepant residues, the amino acid specified by the codon is the same as the corresponding residue in murine SAA. Identification of regions containing coding regions has permitted use of selected subclones for blot hybridization studies of larger human SAA chromosomal gene organization. The third clone, GSAA 3 also contains SAA coding information by DNA sequence analysis but has a different organization which has not yet been fully described. We have reported the isolation of clones of human DNA hybridizing with pRS48 - a plasmid containing a complementary DNA (cDNA) clone for murine serum amyloid A (SAA; 1, 2). We now present more detailed data confirming the identity and defining some of the organizational features of these clones

  12. Using bacterial inclusion bodies to screen for amyloid aggregation inhibitors

    Science.gov (United States)

    2012-01-01

    Background The amyloid-β peptide (Aβ42) is the main component of the inter-neuronal amyloid plaques characteristic of Alzheimer's disease (AD). The mechanism by which Aβ42 and other amyloid peptides assemble into insoluble neurotoxic deposits is still not completely understood and multiple factors have been reported to trigger their formation. In particular, the presence of endogenous metal ions has been linked to the pathogenesis of AD and other neurodegenerative disorders. Results Here we describe a rapid and high-throughput screening method to identify molecules able to modulate amyloid aggregation. The approach exploits the inclusion bodies (IBs) formed by Aβ42 when expressed in bacteria. We have shown previously that these aggregates retain amyloid structural and functional properties. In the present work, we demonstrate that their in vitro refolding is selectively sensitive to the presence of aggregation-promoting metal ions, allowing the detection of inhibitors of metal-promoted amyloid aggregation with potential therapeutic interest. Conclusions Because IBs can be produced at high levels and easily purified, the method overcomes one of the main limitations in screens to detect amyloid modulators: the use of expensive and usually highly insoluble synthetic peptides. PMID:22553999

  13. Amyloid plaque imaging in vivo: current achievement and future prospects

    Energy Technology Data Exchange (ETDEWEB)

    Nordberg, Agneta [Karolinska University Hospital Huddinge, Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Division of Alzheimer Neurobiology, Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Geriatric Medicine, Stockholm (Sweden)

    2008-03-15

    Alzheimer's disease (AD) is a very complex neurodegenerative disorder, the exact cause of which is still not known. The major histopathological features, amyloid plaques and neurofibrillary tangles, already described by Alois Alzheimer, have been the focus in research for decades. Despite a probable whole cascade of events in the brain leading to impairment of cognition, amyloid is still the target for diagnosis and treatment. The rapid development of molecular imaging techniques now allows imaging of amyloid plaques in vivo in Alzheimer patients by PET amyloid ligands such as Pittsburgh compound B (PIB). Studies so far have revealed high {sup 11}C-PIB retention in brain at prodromal stages of AD and a possibility to discriminate AD from other dementia disorders by {sup 11}C-PIB. Ongoing studies are focussing to understand the relationship between brain and CSF amyloid processes and cognitive processes. In vivo imaging of amyloid will be important for early diagnosis and evaluation of new anti-amyloid therapies in AD. (orig.)

  14. Kinetically controlled thermal response of beta2-microglobulin amyloid fibrils.

    Science.gov (United States)

    Sasahara, Kenji; Naiki, Hironobu; Goto, Yuji

    2005-09-23

    Calorimetric measurements were carried out using a differential scanning calorimeter in the temperature range from 10 to 120 degrees C for characterizing the thermal response of beta2-microglobulin amyloid fibrils. The thermograms of amyloid fibril solution showed a remarkably large decrease in heat capacity that was essentially released upon the thermal unfolding of the fibrils, in which the magnitude of negative heat capacity change was not explicable in terms of the current accessible surface area model of protein structural thermodynamics. The heat capacity-temperature curve of amyloid fibrils prior to the fibril unfolding exhibited an unusual dependence on the fibril concentration and the heating rate. Particularly, the heat needed to induce the thermal response was found to be linearly dependent on the heating rate, indicating that its thermal response is under a kinetic control and precluding the interpretation in terms of equilibrium thermodynamics. Furthermore, amyloid fibrils of amyloid beta peptides also exhibited a heating rate-dependent exothermic process before the fibril unfolding, indicating that the kinetically controlled thermal response may be a common phenomenon to amyloid fibrils. We suggest that the heating rate-dependent negative change in heat capacity is coupled to the association of amyloid fibrils with characteristic hydration pattern.

  15. Amyloid plaque imaging in vivo: current achievement and future prospects

    International Nuclear Information System (INIS)

    Nordberg, Agneta

    2008-01-01

    Alzheimer's disease (AD) is a very complex neurodegenerative disorder, the exact cause of which is still not known. The major histopathological features, amyloid plaques and neurofibrillary tangles, already described by Alois Alzheimer, have been the focus in research for decades. Despite a probable whole cascade of events in the brain leading to impairment of cognition, amyloid is still the target for diagnosis and treatment. The rapid development of molecular imaging techniques now allows imaging of amyloid plaques in vivo in Alzheimer patients by PET amyloid ligands such as Pittsburgh compound B (PIB). Studies so far have revealed high 11 C-PIB retention in brain at prodromal stages of AD and a possibility to discriminate AD from other dementia disorders by 11 C-PIB. Ongoing studies are focussing to understand the relationship between brain and CSF amyloid processes and cognitive processes. In vivo imaging of amyloid will be important for early diagnosis and evaluation of new anti-amyloid therapies in AD. (orig.)

  16. Reversible acute axonal polyneuropathy associated with Wernicke-Korsakoff syndrome: impaired physiological nerve conduction due to thiamine deficiency?

    Science.gov (United States)

    Ishibashi, S; Yokota, T; Shiojiri, T; Matunaga, T; Tanaka, H; Nishina, K; Hirota, H; Inaba, A; Yamada, M; Kanda, T; Mizusawa, H

    2003-05-01

    Acute axonal polyneuropathy and Wernicke-Korsakoff encephalopathy developed simultaneously in three patients. Nerve conduction studies (NCS) detected markedly decreased compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) with minimal conduction slowing; sympathetic skin responses (SSRs) were also notably decreased. Sural nerve biopsies showed only mild axonal degeneration with scattered myelin ovoid formation. The symptoms of neuropathy lessened within two weeks after an intravenous thiamine infusion. CMAPs, SNAPs, and SSRs also increased considerably. We suggest that this is a new type of peripheral nerve impairment: physiological conduction failure with minimal conduction delay due to thiamine deficiency.

  17. Amyloid-β and Astrocytes Interplay in Amyloid-β Related Disorders

    Directory of Open Access Journals (Sweden)

    Yazan S. Batarseh

    2016-03-01

    Full Text Available Amyloid-β (Aβ pathology is known to promote chronic inflammatory responses in the brain. It was thought previously that Aβ is only associated with Alzheimer’s disease and Down syndrome. However, studies have shown its involvement in many other neurological disorders. The role of astrocytes in handling the excess levels of Aβ has been highlighted in the literature. Astrocytes have a distinctive function in both neuronal support and protection, thus its involvement in Aβ pathological process may tip the balance toward chronic inflammation and neuronal death. In this review we describe the involvement of astrocytes in Aβ related disorders including Alzheimer’s disease, Down syndrome, cerebral amyloid angiopathy, and frontotemporal dementia.

  18. Evidence of amyloid-β cerebral amyloid angiopathy transmission through neurosurgery.

    Science.gov (United States)

    Jaunmuktane, Zane; Quaegebeur, Annelies; Taipa, Ricardo; Viana-Baptista, Miguel; Barbosa, Raquel; Koriath, Carolin; Sciot, Raf; Mead, Simon; Brandner, Sebastian

    2018-02-15

    Amyloid-β (Aβ) is a peptide deposited in the brain parenchyma in Alzheimer's disease and in cerebral blood vessels, causing cerebral amyloid angiopathy (CAA). Aβ pathology is transmissible experimentally in animals and through medical procedures in humans, such as contaminated growth hormone or dura mater transplantation in the context of iatrogenic prion disease. Here, we present four patients who underwent neurosurgical procedures during childhood or teenage years and presented with intracerebral haemorrhage approximately three decades later, caused by severe CAA. None of these patients carried pathogenic mutations associated with early Aβ pathology development. In addition, we identified in the literature four patients with a history of neurosurgical intervention and subsequent development of CAA. These findings raise the possibility that Aβ pathology may be transmissible, as prion disease is, through neurosurgical procedures.

  19. Static balance in patients presenting diabetes mellitus type 2 with and without diabetic polyneuropathy.

    Science.gov (United States)

    Palma, Felipe H; Antigual, Diego U; Martínez, Sergio F; Monrroy, Manuel A; Gajardo, Rubén E

    2013-12-01

    To contrast the static balance in patients presenting diabetes mellitus type 2 (DM2) with and without polyneuropathy (DPN); and to correlate the rates from the scale Diabetic Neuropathy Examination (DNE) with the mean ratio of the center of pressure (CoP). Twenty patients, aged between 40 and 54, presenting DM2 and classified, according to DNE scale, in groups with (n = 10) and without (n = 10) DPN, were compared. Static balance was evaluated by means of the CoP mean ratio on a Wii Balance Board® under the conditions of open and closed eyes. After normality verification (Shapiro-Wilk), balance between both groups was compared by means of the Student t test and Mann-Whitney U test, as applicable. DNE rating was correlated with the mean ratio of CoP in the group with DPN, considering a significance level p CoP ratio in the group with DPN (0.548 cm vs. 0.442 cm). The group with DPN showed a tendency (p = 0.059) towards a greater CoP mean ratio under the open eyes condition (0.351 cm vs. 0.239 cm). There was a strong correlation (r = 0.751) between the DNE rating and the CoP mean ratio under the closed eyes condition (p = 0.012). Patients showing DPN demonstrated worse static balance than patients without DPN in the closed eyes condition. Furthermore, the higher the rating in DNE, the stronger the displacement of CoP, which may be associated with higher risk of falls.

  20. BAG3-related myopathy, polyneuropathy and cardiomyopathy with long QT syndrome.

    Science.gov (United States)

    Kostera-Pruszczyk, Anna; Suszek, Małgorzata; Płoski, Rafał; Franaszczyk, Maria; Potulska-Chromik, Anna; Pruszczyk, Piotr; Sadurska, Elżbieta; Karolczak, Justyna; Kamińska, Anna M; Rędowicz, Maria Jolanta

    2015-12-01

    BAG3 belongs to BAG family of molecular chaperone regulators interacting with HSP70 and anti-apoptotic protein Bcl-2. It is ubiquitously expressed with strong expression in skeletal and cardiac muscle, and is involved in a panoply of cellular processes. Mutations in BAG3 and aberrations in its expression cause fulminant myopathies, presenting with progressive limb and axial muscle weakness, and respiratory insufficiency and neuropathy. Herein, we report a sporadic case of a 15-years old girl with symptoms of myopathy, demyelinating polyneuropathy and asymptomatic long QT syndrome. Genetic testing demonstrated heterozygous mutation Pro209Leu (c.626C > T) in exon 3 of BAG3 gene causing severe myopathy and neuropathy, often associated with restrictive cardiomyopathy. We did not find a mutation in any known LQT syndrome genes. Analysis of muscle biopsy revealed profound disintegration of Z-discs with extensive accumulation of granular debris and large inclusions within fibers. We demonstrated profound alterations in BAG3 distribution as the protein localized to long filamentous structures present across the fibers that were positively stained not only for α-actinin but also for desmin and filamin indicating that those disintegrated Z-disc regions contained also other sarcomeric proteins. The mutation caused a decrease in the content of BAG3 and HSP70, and also of α-actinin desmin, filamin and fast myosin heavy chain, confirming its severe effect on the muscle fiber morphology and thus function. We provide further evidence that BAG3 is associated with Z-disc maintenance, and the Pro209Leu mutation may occur worldwide. We also provide a summary of cases associated with this mutation reported so far.

  1. Comorbidity of psychiatric disorders and symmetric distal polyneuropathy among type II diabetic outpatients

    Directory of Open Access Journals (Sweden)

    R.O. Moreira

    2007-02-01

    Full Text Available The objective of the present study was to establish the frequency of psychiatric comorbidity in a sample of diabetic patients with symmetric distal polyneuropathy (SDPN. Sixty-five patients with type 2 diabetes mellitus were selected consecutively to participate in the study at Instituto Estadual de Diabetes e Endocrinologia. All patients were submitted to a complete clinical and psychiatric evaluation, including the Portuguese version of the structured clinical interview for DSM-IV, the Beck Depression Inventory, the Neuropathy Symptom Score, and Neuropathy Disability Score. SDPN was identified in 22 subjects (33.8%. Patients with and without SDPN did not differ significantly regarding sociodemographic characteristics. However, a trend toward a worse glycemic control was found in patients with SDPN in comparison to patients without SDPN (HbA1c = 8.43 ± 1.97 vs 7.48 ± 1.95; P = 0.08. Patients with SDPN exhibited axis I psychiatric disorders significantly more often than those without SDPN (especially anxiety disorders, in general (81.8 vs 60.0%; P = 0.01, and major depression - current episode, in particular (18.2 vs 7.7%; P = 0.04. The severity of the depressive symptoms correlated positively with the severity of SDPN symptoms (r = 0.38; P = 0.006, but not with the severity of SDPN signs (r = 0.07; P = 0.56. In conclusion, the presence of SDPN seems to be associated with a trend toward glycemic control. The diagnosis of SDPN in diabetic subjects seems also to be associated with relevant psychiatric comorbidity, including anxiety and current mood disorders.

  2. From treatment to preventive actions: improving function in patients with diabetic polyneuropathy.

    Science.gov (United States)

    Sacco, Isabel C N; Sartor, Cristina D

    2016-01-01

    Diabetic polyneuropathy is an insidious and long-term complication of this disease. Synergistic treatments and preventive actions are crucial because there are no clear boundaries for determining when health professionals should intervene or what intervention would best avoid the consequences of neuropathy. Until now, most therapies to any diabetic individual were applied only after the patient's limb was ulcerated or amputated. The loss of muscle and joint functions is recognized as the main cause of plantar overloading. However, if foot and ankle exercises are performed following the early diagnosis of diabetes, they can enable the patient to maintain sufficient residual function to interact with the environment. This article summarizes the current knowledge about the musculoskeletal deficits and biomechanical alterations caused by neuropathy. It also describes the potential benefits of foot and ankle exercises for any diabetic patient that is not undergoing the plantar ulcer healing process. We concentrate on the prevention of the long-term deficits of neuropathy. We also discuss the main strategies and protocols of therapeutic exercises for joints and muscles with deficits, which are applicable to all diabetic patients with mild to moderate neuropathy. We describe further efforts in exploiting the applicability of assistive technologies to improve the adherence to an exercise program. Following the contemporary trends towards self-monitoring and self-care, we developed a software to monitor and promote personalized exercises with the aim of improving autonomous performance in daily living tasks. Initiatives to prevent the complications of functional diabetes are highly recommended before it is too late for the patient and there is no longer an opportunity to reverse the tragic consequences of neuropathy progression. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Alemtuzumab in the treatment of IVIG-dependent chronic inflammatory demyelinating polyneuropathy.

    LENUS (Irish Health Repository)

    Marsh, E A

    2010-06-01

    Chronic inflammatory demyelinating polyneuropathy (CIDP) is an idiopathic immune mediated neuropathy causing demyelination and conduction block thought to occur as the result of an aberrant autoimmune response resulting in peripheral nerve inflammation mediated by T cells and humoral factors. Diagnosis commonly prompts initial treatment with steroids or intravenous immunoglobulin (IVIG) on which 5-35% subsequently become dependent to maintain function. Despite a number of small scale trials, the role for alternative long-term immunosuppression remains unclear. Alemtuzumab is a humanised monoclonal antibody targeting the CD52 antigen present on the surface of lymphocytes and monocytes. A single intravenous infusion results in rapid and profound lymphopoenia lasting >12 months. We report its use and clinical outcome in a small series of patients with severe IVIG-dependent CIDP. Seven patients (4 Males; 3 Females) who had failed to respond to conventional immunosuppression were treated in 5 centres receiving 9 courses of alemtuzumab (dose range 60-150 mg). Following treatment, mean monthly IVIG use fell 26% from 202 to 149 g and IVIG administration frequency from 22 to 136 days. Two patients had prolonged remission, two patients had a partial response and no clear benefit was observed in the remaining three patients (2 Males, 1 Females). Responding patients had a younger age at onset (19.5 years) and shorter disease duration than non-responders. Three patients developed autoimmune disease following treatment. Alemtuzumab may offer an alternative treatment for a subset of early onset IVIG dependent CIDP patients failing conventional immunosuppressive agents, but concerns about toxicity may limit its use.

  4. Total antioxidant blood capacity in patients with type 2 diabetes mellitus and distal symmetrical polyneuropathy

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    Đorđević Gordana

    2008-01-01

    Full Text Available Background/Aim. Reduced systemic antioxidant defense is considered to play an important mediating role in pathogenesis of diabetic neuropathy. The aim of this study was to evaluate if the total antioxidant blood capacity (TAC is reduced in patients with type 2 diabetes mellitus (DM and diabetic distal symmetrical polyneuropathy (DDSP and to correlate this antioxidant capacity with the degree of peripheral nerve dysfunction. Methods. This study involved 100 patients with type 2 DM and signs of DDSP, as well as the control group of 50 healthy subjects. The evaluation of DDSP was based on physical examination and nerve conduction studies. The degree of peripheral nerve dysfunction was estimated by scoring and analysing sensory and motor nerve conduction parameters (distal latency and amplitude of evoked potential, conduction velocity. Laboratory analyses involved blood glucose and HbA1C levels, as well as plasma TAC. Results. Blood glucose and HbA1C level was significantly higher in the patients than in the control group (p < 0.0001. The TAC was depleted in the diabetic group and the depletion was statistically significant (p < 0.0001. There was no significant correlation between the TAC and the serum glucose level, TAC and HbA1C level as well as between TAC and the duration of DM. There was no significant correlation between TAC and peripheral nerve conduction parameters. Conclusion. Total antioxidant blood capacity is reduced in patients with DDSP, but it does not correlate with blood sugar level, with the duration of DM or with the degree of functional nerve damage. These results show a reduced systemic antioxidant defence in patients with type 2 DM and DDSP. However, it is still unclear to what extent the oxidative stress is a contributing factor or leading cause of diabetic neuropathy, suggesting that further studies are necessary.

  5. Long-term follow-up of Norwegian horses affected with acquired equine polyneuropathy.

    Science.gov (United States)

    Hanche-Olsen, S; Kielland, C; Ihler, C F; Hultin Jäderlund, K

    2017-09-01

    Acquired equine polyneuropathy (AEP), a neurological disease clinically characterised by knuckling of metatarsophalangeal joints, has been described in numerous Nordic horses during the last 20 years. Although clinical recovery has been reported, large-scale data on long-term follow-up of survivors have been lacking. To describe long-term survival of AEP affected horses registered in Norway, with a focus on athletic performance and possible residual clinical signs connected to the disease. A retrospective cohort study. The study includes 143 horses recorded with AEP in Norway from 2000 to 2012, with the follow-up period continuing until 2015. Participating owners of survivors completed a standardised questionnaire, providing information on disease and convalescence, management, performance-level and possible residual clinical signs. To investigate the follow-up of survivors, we performed 2 multivariable linear regression models. The follow-up time of survivors was 1.0-14.5 years (median 5.3, interquartile range 2.5-7.2). Fifty-seven horses survived and all but 3 horses returned to previous or higher level of performance. However, possible disease-related residual clinical signs were reported in 14/57 horses. Forty-nine of the survivors were in athletic use at time of contact. The majority of survivors were categorised with low severity-grades at time of diagnosis and the initial grade was significantly associated with time to resumed training. Only 3 horses had experienced relapse/new attack during the follow-up period. Athletic performance was judged by owners, which renders a possible source of bias. Although AEP is a potential fatal disease, most survivors will recover and return to minimum previous level of athletic performance. Some horses display residual clinical signs, but often without negative effect on performance and relapse of disease is rare. © 2017 EVJ Ltd.

  6. Age, Sex, and APOE ε4 Effects on Memory, Brain Structure, and β-Amyloid Across the Adult Life Span.

    Science.gov (United States)

    Jack, Clifford R; Wiste, Heather J; Weigand, Stephen D; Knopman, David S; Vemuri, Prashanthi; Mielke, Michelle M; Lowe, Val; Senjem, Matthew L; Gunter, Jeffrey L; Machulda, Mary M; Gregg, Brian E; Pankratz, V Shane; Rocca, Walter A; Petersen, Ronald C

    2015-05-01

    Typical cognitive aging may be defined as age-associated changes in cognitive performance in individuals who remain free of dementia. Ideally, the full adult age spectrum should be included to assess brain imaging findings associated with typical aging. To compare age, sex, and APOE ε4 effects on memory, brain structure (adjusted hippocampal volume [HVa]), and amyloid positron emission tomography (PET) in cognitively normal individuals aged 30 to 95 years old. Cross-sectional observational study (March 2006 to October 2014) at an academic medical center. We studied 1246 cognitively normal individuals, including 1209 participants aged 50 to 95 years old enrolled in a population-based study of cognitive aging and 37 self-selected volunteers aged 30 to 49 years old. Memory, HVa, and amyloid PET. Overall, memory worsened from age 30 years through the 90s. The HVa worsened gradually from age 30 years to the mid-60s and more steeply beyond that age. The median amyloid PET was low until age 70 years and increased thereafter. Memory was worse in men than in women overall (P memory performance and HVa were not different by APOE ε4 status at any age. From age 70 years onward, APOE ε4 carriers had significantly greater median amyloid PET than noncarriers. However, the ages at which 10% of the population were amyloid PET positive were 57 years for APOE ε4 carriers and 64 years for noncarriers. Male sex is associated with worse memory and HVa among cognitively normal individuals, while APOE ε4 is not. In contrast, APOE ε4 is associated with greater amyloid PET (from age 70 years onward), while sex is not. Worsening memory and HVa occur at earlier ages than abnormal amyloid PET. Therefore, neuropathological processes other than β-amyloidosis must underlie declines in brain structure and memory function in middle age. Our findings are consistent with a model of late-onset Alzheimer disease in which β-amyloidosis arises in later life on a background of preexisting

  7. Overexpression of heparanase lowers the amyloid burden in amyloid-β precursor protein transgenic mice.

    Science.gov (United States)

    Jendresen, Charlotte B; Cui, Hao; Zhang, Xiao; Vlodavsky, Israel; Nilsson, Lars N G; Li, Jin-Ping

    2015-02-20

    Heparan sulfate (HS) and HS proteoglycans (HSPGs) colocalize with amyloid-β (Aβ) deposits in Alzheimer disease brain and in Aβ precursor protein (AβPP) transgenic mouse models. Heparanase is an endoglycosidase that specifically degrades the unbranched glycosaminoglycan side chains of HSPGs. The aim of this study was to test the hypothesis that HS and HSPGs are active participators of Aβ pathogenesis in vivo. We therefore generated a double-transgenic mouse model overexpressing both human heparanase and human AβPP harboring the Swedish mutation (tgHpa*Swe). Overexpression of heparanase did not affect AβPP processing because the steady-state levels of Aβ1-40, Aβ1-42, and soluble AβPP β were the same in 2- to 3-month-old double-transgenic tgHpa*Swe and single-transgenic tgSwe mice. In contrast, the Congo red-positive amyloid burden was significantly lower in 15-month-old tgHpa*Swe brain than in tgSwe brain. Likewise, the Aβ burden, measured by Aβx-40 and Aβx-42 immunohistochemistry, was reduced significantly in tgHpa*Swe brain. The intensity of HS-stained plaques correlated with the Aβx-42 burden and was reduced in tgHpa*Swe mice. Moreover, the HS-like molecule heparin facilitated Aβ1-42-aggregation in an in vitro Thioflavin T assay. The findings suggest that HSPGs contribute to amyloid deposition in tgSwe mice by increasing Aβ fibril formation because heparanase-induced fragmentation of HS led to a reduced amyloid burden. Therefore, drugs interfering with Aβ-HSPG interactions might be a potential strategy for Alzheimer disease treatment. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Silver ions as em marker of congo red ligation sites in amyloids and amyloid-like aggregates.

    Science.gov (United States)

    Rybarska, Janina; Konieczny, Leszek; Jagusiak, Anna; Chłopaś, Katarzyna; Zemanek, Grzegorz; Piekarska, Barbara; Stopa, Barbara; Piwowar, Piotr; Woźnicka, Olga; Roterman, Irena

    2017-01-01

    Congo red (CR) is a known selective amyloid ligand. The focus of our work is identification (by EM imaging) of dye binding sites and their distribution in amyloids and amyloid-like aggregates formed in vitro. In order to produce the required contrast, CR has been indirectly combined with metal via including Titan yellow (TY) by intercalation which exhibits a relatively strong affinity for silver ions. The resulting combined ligand retains its ability to bind to proteins (which it owes to CR) and can easily be detected in EM studies thanks to TY. We have found, however, that in protein aggregates where unfolding is stabilized by aggregation and therefore is irreversible, TY alone may serve as both, the ligand and the metal carrier. The formation of ordered structures in amyloids was studied using IgG light chains with amyloidogenic properties, converted into amyloids by shaking. The resulting EM images were subjected to interpretation on the basis of the authors' earlier research on the CR/light chain complexation process. Our results indicate that dimeric light chains, which are the subject of our study, produce amyloids or amyloid-like complexes with chain-like properties and strong helicalization tendencies. Cursory analysis suggests that the edge polypeptide loops belonging to unstable light chains form intermolecular bridges which promote creation of loose gel deposits, or are otherwise engaged in the swapping processes leading to higher structural ordering.

  9. Stabilization of a β-hairpin in monomeric Alzheimer's amyloid-β peptide inhibits amyloid formation

    Science.gov (United States)

    Hoyer, Wolfgang; Grönwall, Caroline; Jonsson, Andreas; Ståhl, Stefan; Härd, Torleif

    2008-01-01

    According to the amyloid hypothesis, the pathogenesis of Alzheimer's disease is triggered by the oligomerization and aggregation of the amyloid-β (Aβ) peptide into protein plaques. Formation of the potentially toxic oligomeric and fibrillar Aβ assemblies is accompanied by a conformational change toward a high content of β-structure. Here, we report the solution structure of Aβ(1–40) in complex with the phage-display selected affibody protein ZAβ3, a binding protein of nanomolar affinity. Bound Aβ(1–40) features a β-hairpin comprising residues 17–36, providing the first high-resolution structure of Aβ in β conformation. The positions of the secondary structure elements strongly resemble those observed for fibrillar Aβ. ZAβ3 stabilizes the β-sheet by extending it intermolecularly and by burying both of the mostly nonpolar faces of the Aβ hairpin within a large hydrophobic tunnel-like cavity. Consequently, ZAβ3 acts as a stoichiometric inhibitor of Aβ fibrillation. The selected Aβ conformation allows us to suggest a structural mechanism for amyloid formation based on soluble oligomeric hairpin intermediates. PMID:18375754

  10. Interaction of amyloid inhibitor proteins with amyloid beta peptides: insight from molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Payel Das

    Full Text Available Knowledge of the detailed mechanism by which proteins such as human αB- crystallin and human lysozyme inhibit amyloid beta (Aβ peptide aggregation is crucial for designing treatment for Alzheimer's disease. Thus, unconstrained, atomistic molecular dynamics simulations in explicit solvent have been performed to characterize the Aβ17-42 assembly in presence of the αB-crystallin core domain and of lysozyme. Simulations reveal that both inhibitor proteins compete with inter-peptide interaction by binding to the peptides during the early stage of aggregation, which is consistent with their inhibitory action reported in experiments. However, the Aβ binding dynamics appear different for each inhibitor. The binding between crystallin and the peptide monomer, dominated by electrostatics, is relatively weak and transient due to the heterogeneous amino acid distribution of the inhibitor surface. The crystallin-bound Aβ oligomers are relatively long-lived, as they form more extensive contact surface with the inhibitor protein. In contrast, a high local density of arginines from lysozyme allows strong binding with Aβ peptide monomers, resulting in stable complexes. Our findings not only illustrate, in atomic detail, how the amyloid inhibitory mechanism of human αB-crystallin, a natural chaperone, is different from that of human lysozyme, but also may aid de novo design of amyloid inhibitors.

  11. Amyloid β Oligomeric Species Present in the Lag Phase of Amyloid Formation.

    Directory of Open Access Journals (Sweden)

    Martin Wolff

    Full Text Available Alzheimer's disease (AD-associated amyloid β peptide (Aβ is one of the main actors in AD pathogenesis. Aβ is characterized by its high tendency to self-associate, leading to the generation of oligomers and amyloid fibrils. The elucidation of pathways and intermediates is crucial for the understanding of protein assembly mechanisms in general and in conjunction with neurodegenerative diseases, e.g., for the identification of new therapeutic targets. Our study focused on Aβ42 and its oligomeric assemblies in the lag phase of amyloid formation, as studied by sedimentation velocity (SV centrifugation. The assembly state of Aβ during the lag phase, the time required by an Aβ solution to reach the exponential growth phase of aggregation, was characterized by a dominant monomer fraction below 1 S and a population of oligomeric species between 4 and 16 S. From the oligomer population, two major species close to a 12-mer and an 18-mer with a globular shape were identified. The recurrence of these two species at different initial concentrations and experimental conditions as the smallest assemblies present in solution supports the existence of distinct, energetically favored assemblies in solution. The sizes of the two species suggest an Aβ42 aggregation pathway that is based on a basic hexameric building block. The study demonstrates the potential of SV analysis for the evaluation of protein aggregation pathways.

  12. Impact of peripheral myeloid cells on amyloid-β pathology in Alzheimer's disease-like mice.

    Science.gov (United States)

    Prokop, Stefan; Miller, Kelly R; Drost, Natalia; Handrick, Susann; Mathur, Vidhu; Luo, Jian; Wegner, Anja; Wyss-Coray, Tony; Heppner, Frank L

    2015-10-19

    Although central nervous system-resident microglia are believed to be ineffective at phagocytosing and clearing amyloid-β (Aβ), a major pathological hallmark of Alzheimer's disease (AD), it has been suggested that peripheral myeloid cells constitute a heterogeneous cell population with greater Aβ-clearing capabilities. Here, we demonstrate that the conditional ablation of resident microglia in CD11b-HSVTK (TK) mice is followed by a rapid repopulation of the brain by peripherally derived myeloid cells. We used this system to directly assess the ability of peripheral macrophages to reduce Aβ plaque pathology and therefore depleted and replaced the pool of resident microglia with peripherally derived myeloid cells in Aβ-carrying APPPS1 mice crossed to TK mice (APPPS1;TK). Despite a nearly complete exchange of resident microglia with peripheral myeloid cells, there was no significant change in Aβ burden or APP processing in APPPS1;TK mice. Importantly, however, newly recruited peripheral myeloid cells failed to cluster around Aβ deposits. Even additional anti-Aβ antibody treatment aimed at engaging myeloid cells with amyloid plaques neither directed peripherally derived myeloid cells to amyloid plaques nor altered Aβ burden. These data demonstrate that mere recruitment of peripheral myeloid cells to the brain is insufficient in substantially clearing Aβ burden and suggest that specific additional triggers appear to be required to exploit the full potential of myeloid cell-based therapies for AD. © 2015 Prokop et al.

  13. APOE ε4 influences β-amyloid deposition in primary progressive aphasia and speech apraxia.

    Science.gov (United States)

    Josephs, Keith A; Duffy, Joseph R; Strand, Edythe A; Machulda, Mary M; Senjem, Matthew L; Lowe, Val J; Jack, Clifford R; Whitwell, Jennifer L

    2014-11-01

    Apolipoprotein E ε4 (APOE ε4) is a risk factor for β-amyloid deposition in Alzheimer's disease dementia. Its influence on β-amyloid deposition in speech and language disorders, including primary progressive aphasia (PPA), is unclear. One hundred thirty subjects with PPA or progressive speech apraxia underwent APOE genotyping and Pittsburgh compound B (PiB) PET scanning. The relationship between APOE ε4 and PiB status, as well as severity and regional distribution of PiB, was assessed. Forty-five subjects had an APOE ε4 allele and 60 subjects were PiB-positive. The odds ratio for a subject with APOE ε4 being PiB-positive compared with a subject without APOE ε4 being PiB-positive was 10.2 (95% confidence interval, 4.4-25.5; P speech apraxia but does not influence regional β-amyloid distribution or severity. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  14. In vitro binding of [³H]PIB to human amyloid deposits of different types.

    Science.gov (United States)

    Hellström-Lindahl, Ewa; Westermark, Per; Antoni, Gunnar; Estrada, Sergio

    2014-03-01

    Systemic amyloidosis is caused by extracellular deposition of insoluble fibrillar proteins arranged in β-pleated sheets. [(11)C]PIB has been used in PET studies to assess Aβ deposition in brain of patients with Alzheimer's disease (AD). The possibility to visualize other types of amyloid deposits with [(11)C]PIB would be of potential clinical importance in early diagnosis and for following therapeutic effects. In the present study, we evaluated in vitro binding of [(3)H]PIB to tissues containing transthyretin (ATTR), immunoglobulin light-chain (AL), amyloid protein A (AA) and Aβ amyloid. We found significantly higher binding of [(3)H]PIB in tissue from systemic amyloidoses than in control tissue, i.e. 4.7 times higher (p PIB showed the highest affinity to cortex of AD brain (IC50 = 3.84 nM), while IC50 values were much higher for ATTR, AA and AL type of amyloidosis and large variations in affinity were observed even within tissues having the same type of amyloidosis. Extraction with guanidine-HCl, which disrupts the β-sheet structure, decreased the protein levels and, concomitantly, the binding of [(3)H]PIB in all four types of amyloidoses.

  15. Brain-predicted age in Down syndrome is associated with beta amyloid deposition and cognitive decline.

    Science.gov (United States)

    Cole, James H; Annus, Tiina; Wilson, Liam R; Remtulla, Ridhaa; Hong, Young T; Fryer, Tim D; Acosta-Cabronero, Julio; Cardenas-Blanco, Arturo; Smith, Robert; Menon, David K; Zaman, Shahid H; Nestor, Peter J; Holland, Anthony J

    2017-08-01

    Individuals with Down syndrome (DS) are more likely to experience earlier onset of multiple facets of physiological aging. This includes brain atrophy, beta amyloid deposition, cognitive decline, and Alzheimer's disease-factors indicative of brain aging. Here, we employed a machine learning approach, using structural neuroimaging data to predict age (i.e., brain-predicted age) in people with DS (N = 46) and typically developing controls (N = 30). Chronological age was then subtracted from brain-predicted age to generate a brain-predicted age difference (brain-PAD) score. DS participants also underwent [ 11 C]-PiB positron emission tomography (PET) scans to index the levels of cerebral beta amyloid deposition, and cognitive assessment. Mean brain-PAD in DS participants' was +2.49 years, significantly greater than controls (p brain-PAD was associated with the presence and the magnitude of PiB-binding and levels of cognitive performance. Our study indicates that DS is associated with premature structural brain aging, and that age-related alterations in brain structure are associated with individual differences in the rate of beta amyloid deposition and cognitive impairment. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Toluidine blue O modifies hippocampal amyloid pathology in a transgenic mouse model of Alzheimer's disease.

    Science.gov (United States)

    Yuksel, Melike; Biberoglu, Kevser; Onder, Seda; Akbulut, K Gonca; Tacal, Ozden

    2018-03-01

    Recently, we have demonstrated that toluidine blue O (TBO), a phenothiazine dye, shows inhibitory effects on both cholinesterases and amyloid pathology in Alzheimer's disease (AD) cellular model. In the present study, we aimed to determine the effects of TBO (in a purity of 85%) on amyloid and tau pathologies in a triple transgenic mouse model of AD (3xTg-AD). Beginning at 7.5 (mild pathology) or 13 (severe pathology) months of age, 3xTg-AD mice were treated intraperitoneally with 4 mg/kg TBO or vehicle daily for 30 days. TBO treatment significantly reduced the levels of insoluble Aβ40 and Aβ42 in the hippocampi of mild and severe pathology groups compared to vehicle-treated counterparts. When the levels of full-length amyloid precursor protein (APP) and β-site APP-cleaving enzyme 1 (BACE1) were assessed in 3xTg-AD mice at late pathological stage, no significant changes were observed after TBO treatment. Similarly, TBO did not recover hyperphosphorylation of tau at residues Thr181 and Ser202/Thr205 significantly in soluble and insoluble hippocampal fractions of 3xTg-AD mice. Taken together, the current study is the first in vivo report, to our knowledge, demonstrating that TBO mitigates amyloid pathology in 3xTg-AD mice with no apparent change on tau phosphorylation. Overall, the preliminary data presented here support the possible use of TBO as a disease-modifying drug for AD treatment. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  17. Chinese herbal medicine TangBi Formula treatment of patients with type 2 diabetic distal symmetric polyneuropathy disease: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Jin, De; Huang, Wen-Jing; Meng, Xiang; Yang, Fan; Zheng, Yu-Jiao; Bao, Qi; Zhang, Mei-Zhen; Yang, Ya-Nan; Ni, Qing; Lian, Feng-Mei; Tong, Xiao-Lin

    2017-12-29

    Diabetic distal symmetric polyneuropathy (DSPN) is one of the most common microvascular complications of diabetes mellitus, and it has become a major public health problem worldwide because of its high and increasing prevalence, morbidity, and disability rate. The current medications for DSPN are not entirely satisfactory. Preliminary studies indicated that the Chinese herbal TangBi Formula may alleviate signs and symptoms and improve the velocity of nerve conduction in patients with DSPN. This study was designed to determine if Chinese herbal medicine used in combination with conventional treatment is more effective than conventional treatment alone. We are conducting a multicenter, placebo-controlled, double-blind, randomized, controlled clinical trial as a means of assessing the therapeutic effects of traditional Chinese medicine (TCM) treatment. A total of 188 patients will be randomized in a 1:1 ratio to a treatment group (TangBi Formula plus mecobalamin) and a control group (placebo plus mecobalamin). The test period lasts 6 months, during which all of the patients will be given standard medical care as recommended by established guidelines. The primary outcome will be development of differences in changes in clinical symptoms and signs in patients and changes in Michigan Diabetic Neuropathy Score (MDNS) between the two groups before and after treatment. The secondary outcome will be changes in nerve conduction velocity and in single clinical signs and symptoms. Safety assessments and adverse events will also be evaluated. We postulate that patients with DSPN will benefit from therapy that includes TCM. If successful, this work will provide an evidence-based complementary therapeutic approach for treatment of DSPN. ClinicalTrials.gov, NCT03010241 . Registered on 2 January 2017.

  18. Electrochemistry of Alzheimer disease amyloid beta peptides.

    Science.gov (United States)

    Chiorcea-Paquim, Ana-Maria; Enache, Teodor Adrian; Oliveira-Brett, Ana Maria

    2018-02-13

    Alzheimer's disease (AD) is a widespread form of dementia that is estimated to affect 44.4 million people worldwide. AD pathology is closely related to the accumulation of amyloid beta (Aβ) peptides in fibrils and plagues, the small oligomeric intermediate species formed during the Aβ peptides aggregation presenting the highest neurotoxicity. This review discusses the recent advances on the Aβ peptides electrochemical characterisation. The Aβ peptides oxidation at a glassy carbon electrode occurs in one or two steps, depending on the amino acid sequence, length and content. The first electron transfer reaction corresponds to the tyrosine Tyr10 amino acid residue oxidation, and the second to all three histidine (His6, His13 and His14) and one methionine (Met35) amino acid residues. The Aβ peptides aggregation and amyloid fibril formation is electrochemically detected via the electroactive amino acids oxidation peak currents decrease that occurs in a time dependent manner. The Aβ peptides redox behaviour is correlated with changes in the adsorption morphology from initially random coiled structures, corresponding to the Aβ peptide monomers in random coil or in α-helix conformations, to aggregates and protofibrils and two types of fibrils, corresponding to the Aβ peptides in a β-sheet configuration, observed by atomic force microscopy. Electrochemical studies of Aβ peptides aggregation, mediated by the interaction with metal ions, in particular zinc, copper, and iron, and different methodologies concerning the detection of Aβ peptide biomarkers of AD in biological fluids, using electrochemical biosensors, are also discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Mutations in HADHB, which encodes the β-subunit of mitochondrial trifunctional protein, cause infantile onset hypoparathyroidism and peripheral polyneuropathy.

    Science.gov (United States)

    Naiki, Misako; Ochi, Nobuhiko; Kato, Yusuke S; Purevsuren, Jamiyan; Yamada, Kenichiro; Kimura, Reiko; Fukushi, Daisuke; Hara, Shinya; Yamada, Yasukazu; Kumagai, Toshiyuki; Yamaguchi, Seiji; Wakamatsu, Nobuaki

    2014-05-01

    Mitochondrial trifunctional protein (MTP) is a hetero-octamer composed of four α- and four β-subunits that catalyzes the final three steps of mitochondrial β-oxidation of long chain fatty acids. HADHA and HADHB encode the α-subunit and the β-subunit of MTP, respectively. To date, only two cases with MTP deficiency have been reported to be associated with hypoparathyroidism and peripheral polyneuropathy. Here, we report on two siblings with autosomal recessive infantile onset hypoparathyroidism, peripheral polyneuropathy, and rhabdomyolysis. Sequence analysis of HADHA and HADHB in both siblings shows that they were homozygous for a mutation in exon 14 of HADHB (c.1175C>T, [p.A392V]) and the parents were heterozygous for the mutation. Biochemical analysis revealed that the patients had MTP deficiency. Structural analysis indicated that the A392V mutation identified in this study and the N389D mutation previously reported to be associated with hypoparathyroidism are both located near the active site of MTP and affect the conformation of the β-subunit. Thus, the present patients are the second and third cases of MTP deficiency associated with missense HADHB mutation and infantile onset hypoparathyroidism. Since MTP deficiency is a treatable disease, MTP deficiency should be considered when patients have hypoparathyroidism as the initial presenting feature in infancy. © 2014 Wiley Periodicals, Inc.

  20. The proton-pump inhibitor lansoprazole enhances amyloid beta production.

    Science.gov (United States)

    Badiola, Nahuai; Alcalde, Victor; Pujol, Albert; Münter, Lisa-Marie; Multhaup, Gerd; Lleó, Alberto; Coma, Mireia; Soler-López, Montserrat; Aloy, Patrick

    2013-01-01

    A key event in the pathogenesis of Alzheimer's disease (AD) is the accumulation of amyloid-β (Aβ) species in the brain, derived from the sequential cleavage of the amyloid precursor protein (APP) by β- and γ-secretases. Based on a systems biology study to repurpose drugs for AD, we explore the effect of lansoprazole, and other proton-pump inhibitors (PPIs), on Aβ production in AD cellular and animal models. We found that lansoprazole enhances Aβ37, Aβ40 and Aβ42 production and lowers Aβ38 levels on amyloid cell models. Interestingly, acute lansoprazole treatment in wild type and AD transgenic mice promoted higher Aβ40 levels in brain, indicating that lansoprazole may also exacerbate Aβ production in vivo. Overall, our data presents for the first time that PPIs can affect amyloid metabolism, both in vitro and in vivo.

  1. The effect of tachykinin neuropeptides on amyloid β aggregation.

    Science.gov (United States)

    Flashner, Efrat; Raviv, Uri; Friedler, Assaf

    2011-04-01

    A hallmark of Alzheimer's disease is production of amyloid β peptides resulting from aberrant cleavage of the amyloid precursor protein. Amyloid β assembles into fibrils under physiological conditions, through formation of neurotoxic intermediate oligomers. Tachykinin peptides are known to affect amyloid β neurotoxicity in cells. To understand the mechanism of this effect, we studied how tachykinins affect Aβ(1-40) aggregation in vitro. Fibrils grown in the presence of tachykinins exhibited reduced thioflavin T (ThT) fluorescence, while their morphology, observed in transmission electron microscopy (TEM), did not alter. Cross linking studies revealed that the distribution of low molecular weight species was not affected by tachykinins. Our results suggest that there may be a specific interaction between tachykinins and Aβ(1-40) that allows them to co-assemble. This effect may explain the reduction of Aβ(1-40) neurotoxicity in cells treated with tachykinins. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Prevalence of cerebral amyloid pathology in persons without dementia

    DEFF Research Database (Denmark)

    Jansen, Willemijn J; Ossenkoppele, Rik; Knol, Dirk L

    2015-01-01

    or in cerebrospinal fluid according to AD risk factors (age, apolipoprotein E [APOE] genotype, sex, and education) estimated by generalized estimating equations. RESULTS: The prevalence of amyloid pathology increased from age 50 to 90 years from 10% (95% CI, 8%-13%) to 44% (95% CI, 37%-51%) among participants...... with normal cognition were amyloid positive was approximately 40 years for APOE ε4ε4 carriers, 50 years for ε2ε4 carriers, 55 years for ε3ε4 carriers, 65 years for ε3ε3 carriers, and 95 years for ε2ε3 carriers. Amyloid positivity was more common in highly educated participants but not associated with sex....... OBJECTIVE: To use individual participant data meta-analysis to estimate the prevalence of amyloid pathology as measured with biomarkers in participants with normal cognition, subjective cognitive impairment (SCI), or mild cognitive impairment (MCI). DATA SOURCES: Relevant biomarker studies identified...

  3. Mechanism of prion propagation: amyloid growth occurs by monomer addition.

    Directory of Open Access Journals (Sweden)

    Sean R Collins

    2004-10-01

    Full Text Available Abundant nonfibrillar oligomeric intermediates are a common feature of amyloid formation, and these oligomers, rather than the final fibers, have been suggested to be the toxic species in some amyloid diseases. Whether such oligomers are critical intermediates for fiber assembly or form in an alternate, potentially separable pathway, however, remains unclear. Here we study the polymerization of the amyloidogenic yeast prion protein Sup35. Rapid polymerization occurs in the absence of observable intermediates, and both targeted kinetic and direct single-molecule fluorescence measurements indicate that fibers grow by monomer addition. A three-step model (nucleation, monomer addition, and fiber fragmentation accurately accounts for the distinctive kinetic features of amyloid formation, including weak concentration dependence, acceleration by agitation, and sigmoidal shape of the polymerization time course. Thus, amyloid growth can occur by monomer addition in a reaction distinct from and competitive with formation of potentially toxic oligomeric intermediates.

  4. Imaging amyloid beta peptide oligomeric particles in solution.

    Science.gov (United States)

    Dong, Jijun; Apkarian, Robert P; Lynn, David G

    2005-09-01

    While all protein misfolding diseases are characterized by fibrous amyloid deposits, the favorable free energy and strongly cooperative nature of the self-assembly have complicated the development of therapeutic strategies aimed at preventing their formation. As structural models for the amyloid fibrils approach atomic resolution, increasing evidence suggests that early folding intermediates, rather than the final structure, are more strongly associated with the loss of neuronal function. For that reason we now demonstrate the use of cryo-etch high-resolution scanning electron microscopy (cryo-HRSEM) for the direct observation of pathway intermediates in amyloid assembly. A congener of the Abeta peptide of Alzheimer's disease, Abeta(13-21), samples a variety of time-dependent self-assembles in a manner similar to those seen for larger proteins. A morphological description of these intermediates is the first step towards their structural characterization and the definition of their role in both amyloid assembly and neurotoxicity.

  5. Interactions driving the collapse of islet amyloid polypeptide: Implications for amyloid aggregation

    Science.gov (United States)

    Cope, Stephanie M.

    Human islet amyloid polypeptide (hIAPP), also known as amylin, is a 37-residue intrinsically disordered hormone involved in glucose regulation and gastric emptying. The aggregation of hIAPP into amyloid fibrils is believed to play a causal role in type 2 diabetes. To date, not much is known about the monomeric state of hIAPP or how it undergoes an irreversible transformation from disordered peptide to insoluble aggregate. IAPP contains a highly conserved disulfide bond that restricts hIAPP(1-8) into a short ring-like structure: N_loop. Removal or chemical reduction of N_loop not only prevents cell response upon binding to the CGRP receptor, but also alters the mass per length distribution of hIAPP fibers and the kinetics of fibril formation. The mechanism by which N_loop affects hIAPP aggregation is not yet understood, but is important for rationalizing kinetics and developing potential inhibitors. By measuring end-to-end contact formation rates, Vaiana et al. showed that N_loop induces collapsed states in IAPP monomers, implying attractive interactions between N_loop and other regions of the disordered polypeptide chain . We show that in addition to being involved in intra-protein interactions, the N_loop is involved in inter-protein interactions, which lead to the formation of extremely long and stable beta-turn fibers. These non-amyloid fibers are present in the 10 muM concentration range, under the same solution conditions in which hIAPP forms amyloid fibers. We discuss the effect of peptide cyclization on both intra- and inter-protein interactions, and its possible implications for aggregation. Our findings indicate a potential role of N_loop-N_loop interactions in hIAPP aggregation, which has not previously been explored. Though our findings suggest that N_loop plays an important role in the pathway of amyloid formation, other naturally occurring IAPP variants that contain this structural feature are incapable of forming amyloids. For example, hIAPP readily

  6. Urinary Methylmalonic Acid as an Indicator of Early Vitamin B12 Deficiency and Its Role in Polyneuropathy in Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Ai-li Sun

    2014-01-01

    Full Text Available The rising incidence of diabetes and its negative impact on quality of life highlights the urgent need to develop biomarkers of early nerve damage. Measurement of total vitamin B12 has some limitations. We want to determine the levels of urinary methylmalonic acid and its relationships with serum vitamin B12 and polyneuropathy. The 176 Chinese patients with Type 2 diabetes mellitus were divided into 3 groups according to the levels of vitamin B12. A gas chromatography mass spectrometric technique was used to determine blood methylmalonic acid and urinary methylmalonic acid. The diagnosis of distal diabetic polyneuropathy was based on the determination of bilateral limb sensory and motor nerve conduction velocity and amplitude with electromyogram. Multiple regression analysis revealed that urinary methylmalonic acid/creatinine, blood methylmalonic acid, and so forth were variables that influenced diabetic polyneuropathy significantly. Nerve sensory conduction velocity and nerve amplitude in the group of urinary methylmalonic acid/creatinine >3.5 mmol/mol decreased significantly. Superficial peroneal nerve sensory and motor conduction velocity and ulnar nerve compound motor active potential amplitude were inversely correlated with urinary methylmalonic acid/creatinine. Urinary methylmalonic acid correlates with serum vitamin B12 levels in person with diabetes and is a sensitive marker of early polyneuropathy.

  7. Urinary methylmalonic acid as an indicator of early vitamin B12 deficiency and its role in polyneuropathy in type 2 diabetes.

    Science.gov (United States)

    Sun, Ai-li; Ni, Yi-hong; Li, Xiao-bo; Zhuang, Xiang-hua; Liu, Yuan-tao; Liu, Xin-hua; Chen, Shi-hong

    2014-01-01

    The rising incidence of diabetes and its negative impact on quality of life highlights the urgent need to develop biomarkers of early nerve damage. Measurement of total vitamin B12 has some limitations. We want to determine the levels of urinary methylmalonic acid and its relationships with serum vitamin B12 and polyneuropathy. The 176 Chinese patients with Type 2 diabetes mellitus were divided into 3 groups according to the levels of vitamin B12. A gas chromatography mass spectrometric technique was used to determine blood methylmalonic acid and urinary methylmalonic acid. The diagnosis of distal diabetic polyneuropathy was based on the determination of bilateral limb sensory and motor nerve conduction velocity and amplitude with electromyogram. Multiple regression analysis revealed that urinary methylmalonic acid/creatinine, blood methylmalonic acid, and so forth were variables that influenced diabetic polyneuropathy significantly. Nerve sensory conduction velocity and nerve amplitude in the group of urinary methylmalonic acid/creatinine >3.5 mmol/mol decreased significantly. Superficial peroneal nerve sensory and motor conduction velocity and ulnar nerve compound motor active potential amplitude were inversely correlated with urinary methylmalonic acid/creatinine. Urinary methylmalonic acid correlates with serum vitamin B12 levels in person with diabetes and is a sensitive marker of early polyneuropathy.

  8. A RHIM with a View: FLYing with Functional Amyloids.

    Science.gov (United States)

    Shin, Sunny; Cherry, Sara

    2017-10-17

    Recognition of bacterial peptidoglycan by the Drosophila IMD pathway triggers NF-κB activation and an associated immune response. In this issue of Immunity, Kleino et al. (2017) show that proteins in the IMD pathway form functional amyloids via a cryptic motif resembling the RHIM motif found in mammalian RIPK proteins. Amyloid formation can be negatively regulated, suggesting that it presents a regulatory point in multiple biological processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Light Chain Amyloid Fibrils Cause Metabolic Dysfunction in Human Cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Helen P McWilliams-Koeppen

    Full Text Available Light chain (AL amyloidosis is the most common form of systemic amyloid disease, and cardiomyopathy is a dire consequence, resulting in an extremely poor prognosis. AL is characterized by the production of monoclonal free light chains that deposit as amyloid fibrils principally in the heart, liver, and kidneys causing organ dysfunction. We have studied the effects of amyloid fibrils, produced from recombinant λ6 light chain variable domains, on metabolic activity of human cardiomyocytes. The data indicate that fibrils at 0.1 μM, but not monomer, significantly decrease the enzymatic activity of cellular NAD(PH-dependent oxidoreductase, without causing significant cell death. The presence of amyloid fibrils did not affect ATP levels; however, oxygen consumption was increased and reactive oxygen species were detected. Confocal fluorescence microscopy showed that fibrils bound to and remained at the cell surface with little fibril internalization. These data indicate that AL amyloid fibrils severely impair cardiomyocyte metabolism in a dose dependent manner. These data suggest that effective therapeutic intervention for these patients should include methods for removing potentially toxic amyloid fibrils.

  10. Thermal Stability Threshold for Amyloid Formation in Light Chain Amyloidosis

    Directory of Open Access Journals (Sweden)

    Tanya L. Poshusta

    2013-11-01

    Full Text Available Light chain (AL amyloidosis is a devastating disease characterized by amyloid deposits formed by immunoglobulin light chains. Current available treatments involve conventional chemotherapy and autologous stem cell transplant. We have recently concluded a phase III trial comparing these two treatments. AL amyloidosis patients who achieve hematological complete response (CR do not necessarily achieve organ response regardless of the treatment they received. In order to investigate the possible correlation between amyloid formation kinetics and organ response, we selected AL amyloidosis patients from the trial with kidney involvement and CR after treatment. Six patients were selected and their monoclonal immunoglobulin light chains were characterized. The proteins showed differences in their stability and their kinetics of amyloid formation. A correlation was detected at pH 7.4, showing that less stable proteins are more likely to form amyloid fibrils. AL-T03 is too unstable to form amyloid fibrils at pH 7.4. This protein was found in the only patient in the study that had organ response, suggesting that partially folded species are required for amyloid formation to occur in AL amyloidosis.

  11. PMEL Amyloid Fibril Formation: The Bright Steps of Pigmentation

    Directory of Open Access Journals (Sweden)

    Christin Bissig

    2016-08-01

    Full Text Available In pigment cells, melanin synthesis takes place in specialized organelles, called melanosomes. The biogenesis and maturation of melanosomes is initiated by an unpigmented step that takes place prior to the initiation of melanin synthesis and leads to the formation of luminal fibrils deriving from the pigment cell-specific pre-melanosomal protein (PMEL. In the lumen of melanosomes, PMEL fibrils optimize sequestration and condensation of the pigment melanin. Interestingly, PMEL fibrils have been described to adopt a typical amyloid-like structure. In contrast to pathological amyloids often associated with neurodegenerative diseases, PMEL fibrils represent an emergent category of physiological amyloids due to their beneficial cellular functions. The formation of PMEL fibrils within melanosomes is tightly regulated by diverse mechanisms, such as PMEL traffic, cleavage and sorting. These mechanisms revealed increasing analogies between the formation of physiological PMEL fibrils and pathological amyloid fibrils. In this review we summarize the known mechanisms of PMEL fibrillation and discuss how the recent understanding of physiological PMEL amyloid formation may help to shed light on processes involved in pathological amyloid formation.

  12. Toxic species in amyloid disorders: Oligomers or mature fibrils

    Directory of Open Access Journals (Sweden)

    Meenakshi Verma

    2015-01-01

    Full Text Available Protein aggregation is the hallmark of several neurodegenerative disorders. These protein aggregation (fibrillization disorders are also known as amyloid disorders. The mechanism of protein aggregation involves conformation switch of the native protein, oligomer formation leading to protofibrils and finally mature fibrils. Mature fibrils have long been considered as the cause of disease pathogenesis; however, recent evidences suggest oligomeric intermediates formed during fibrillization to be toxic. In this review, we have tried to address the ongoing debate for these toxic amyloid species. We did an extensive literature search and collated information from Pubmed (http://www.ncbi.nlm.nih.gov and Google search using various permutations and combinations of the following keywords: Neurodegeneration, amyloid disorders, protein aggregation, fibrils, oligomers, toxicity, Alzheimer′s Disease, Parkinson′s Disease. We describe different instances showing the toxicity of mature fibrils as well as oligomers in Alzheimer′s Disease and Parkinson′s Disease. Distinct structural framework and morphology of amyloid oligomers suggests difference in toxic effect between oligomers and fibrils. We highlight the difference in structure and proposed toxicity pathways for fibrils and oligomers. We also highlight the evidences indicating that intermediary oligomeric species can act as potential diagnostic biomarker. Since the formation of these toxic species follow a common structural switch among various amyloid disorders, the protein aggregation events can be targeted for developing broad-range therapeutics. The therapeutic trials based on the understanding of different protein conformers (monomers, oligomers, protofibrils and fibrils in amyloid cascade are also described.

  13. Amyloid Imaging: Poised for Integration into Medical Practice.

    Science.gov (United States)

    Anand, Keshav; Sabbagh, Marwan

    2017-01-01

    Amyloid imaging represents a significant advance as an adjunct in the diagnosis of Alzheimer's disease (AD) because it is the first imaging modality that identifies in vivo changes known to be associated with the pathogenesis. Initially, 11 C-PIB was developed, which was the prototype for many 18 F compounds, including florbetapir, florbetaben, and flutemetamol, among others. Despite the high sensitivity and specificity of amyloid imaging, it is not commonly used in clinical practice, mainly because it is not reimbursed under current Center for Medicare and Medicaid Services guidelines in the USA. To guide the field in who would be most appropriate for the utility of amyloid positron emission tomography, current studies are underway [Imaging Dementia Evidence for Amyloid Scanning (IDEAS) Study] that will inform the field on the utilization of amyloid positron emission tomography in clinical practice. With the advent of monoclonal antibodies that specifically target amyloid antibody, there is an interest, possibly a mandate, to screen potential treatment recipients to ensure that they are suitable for treatment. In this review, we summarize progress in the field to date.

  14. Detection of amyloid fibrils in Parkinson's disease using plasmonic chirality.

    Science.gov (United States)

    Kumar, Jatish; Eraña, Hasier; López-Martínez, Elena; Claes, Nathalie; Martín, Víctor F; Solís, Diego M; Bals, Sara; Cortajarena, Aitziber L; Castilla, Joaquín; Liz-Marzán, Luis M

    2018-03-27

    Amyloid fibrils, which are closely associated with various neurodegenerative diseases, are the final products in many protein aggregation pathways. The identification of fibrils at low concentration is, therefore, pivotal in disease diagnosis and development of therapeutic strategies. We report a methodology for the specific identification of amyloid fibrils using chiroptical effects in plasmonic nanoparticles. The formation of amyloid fibrils based on α-synuclein was probed using gold nanorods, which showed no apparent interaction with monomeric proteins but effective adsorption onto fibril structures via noncovalent interactions. The amyloid structure drives a helical nanorod arrangement, resulting in intense optical activity at the surface plasmon resonance wavelengths. This sensing technique was successfully applied to human brain homogenates of patients affected by Parkinson's disease, wherein protein fibrils related to the disease were identified through chiral signals from Au nanorods in the visible and near IR, whereas healthy brain samples did not exhibit any meaningful optical activity. The technique was additionally extended to the specific detection of infectious amyloids formed by prion proteins, thereby confirming the wide potential of the technique. The intense chiral response driven by strong dipolar coupling in helical Au nanorod arrangements allowed us to detect amyloid fibrils down to nanomolar concentrations.

  15. Amyloid- and FDG-PET in sporadic Creutzfeldt-Jakob disease: Correlation with pathological prion protein in neuropathology.

    Science.gov (United States)

    Matías-Guiu, Jordi A; Guerrero-Márquez, Carmen; Cabrera-Martín, María Nieves; Gómez-Pinedo, Ulises; Romeral, María; Mayo, Diego; Porta-Etessam, Jesús; Moreno-Ramos, Teresa; Carreras, José Luis; Matías-Guiu, Jorge

    2017-05-04

    The role of positron emission tomography (PET) in Creutzfeldt-Jakob disease is less defined than in other neurodegenerative diseases. We studied the correlation between the uptake of 18 F-florbetaben and 18 F-fluorodeoxyglucose with pathological prion protein deposition in histopathology in a case. A patient with 80 y old with a rapid neurological deterioration with a confirmed diagnosis of CJD was studied. PET and MRI studies were performed between 13-20 d before the death. A region of interest analysis was performed using Statistical Parametric Mapping. MRI showed atrophy with no other alterations. FDG-PET showed extensive areas of hypometabolism including left frontoparietal lobes as well as bilateral thalamus. Correlation between uptake of 18 F-florbetaben and pathological prion protein deposition was r = 0.786 (p < 0.05). Otherwise, correlation between uptake of 18 F-FDG and pathological prion protein was r = 0.357 (p = 0.385). Immunohistochemistry with β-amyloid did not show amyloid deposition or neuritic plaques. Our study supports the use of FDG-PET in the assessment of CJD. FDG-PET may be especially useful in cases of suspected CJD and negative MRI. Furthermore, this case report provides more evidence about the behavioral of amyloid tracers, and the possibility of a low-affinity binding to other non-amyloid proteins, such as the pathological prion protein, is discussed.

  16. Utility of Amyloid and FDG-PET in Clinical Practice: Differences Between Secondary and Tertiary Care Memory Units.

    Science.gov (United States)

    Lage, Carmen; Suarez, Andrea Gonzalez; Pozueta, Ana; Riancho, Javier; Kazimierczak, Martha; Bravo, Maria; Jimenez Bonilla, Julio; de Arcocha Torres, Marıa; Quirce, Remedios; Banzo, Ignacio; Vazquez-Higuera, Jose Luis; Rabinovici, Gil D; Rodriguez-Rodriguez, Eloy; Sánchez-Juan, Pascual

    2018-04-27

    The clinical utility of amyloid positron emission tomography (PET) has not been fully established. Our aim was to evaluate the effect of amyloid imaging on clinical decision making in a secondary care unit and compare our results with a previous study in a tertiary center following the same methods. We reviewed retrospectively 151 cognitively impaired patients who underwent amyloid (Pittsburgh compound B [PiB]) PET and were evaluated clinically before and after the scan in a secondary care unit. One hundred and fifty concurrently underwent fluorodeoxyglucose (FDG)-PET. We assessed changes between the pre- and post-PET clinical diagnosis and Alzheimer's disease treatment plan. The association between PiB/FDG results and changes in management was evaluated using χ2 and multivariate logistic regression. Concordance between classification based on scan readings and baseline diagnosis was 66% for PiB and 47% for FDG. The primary diagnosis changed after PET in 17.2% of cases. When examined independently, discordant PiB and discordant FDG were both associated with diagnostic change (p PET due to a higher likelihood of diagnostic change. We found that changes in diagnosis after PET in our secondary center almost doubled those of our previous analysis of a tertiary unit (9% versus 17.2%). Our results offer some clues about the rational use of amyloid PET in a secondary care memory unit stressing its utility in mild cognitive impairment patients.

  17. Nasal administration of amyloid-beta peptide decreases cerebral amyloid burden in a mouse model of Alzheimer's disease

    DEFF Research Database (Denmark)

    Weiner, H L; Lemere, C A; Maron, R

    2000-01-01

    Progressive cerebral deposition of amyloid-beta (Abeta) peptide, an early and essential feature of Alzheimer's disease (AD), is accompanied by an inflammatory reaction marked by microgliosis, astrocytosis, and the release of proinflammatory cytokines. Mucosal administration of disease-implicated ......Progressive cerebral deposition of amyloid-beta (Abeta) peptide, an early and essential feature of Alzheimer's disease (AD), is accompanied by an inflammatory reaction marked by microgliosis, astrocytosis, and the release of proinflammatory cytokines. Mucosal administration of disease...

  18. Measurement of cooling detection thresholds for identification of diabetic sensorimotor polyneuropathy in type 1 diabetes.

    Directory of Open Access Journals (Sweden)

    Zoe Lysy

    Full Text Available OBJECTIVE: Compared to recently-studied novel morphological measures, conventional small nerve fiber functional tests have not been systematically studied for identification of diabetic sensorimotor polyneuropathy (DSP. We aimed to determine and compare the diagnostic performance of cooling detection thresholds (CDT in a cross-sectional type 1 diabetes cohort. RESEARCH DESIGN AND METHODS: 136 subjects with type 1 diabetes and 52 healthy volunteers underwent clinical and electrophysiological examination for DSP classification concomitantly with the Toronto Clinical Neuropathy Score (TCNS and three small fiber function tests: CDT, heart rate variability (HRV, and laser doppler imaging of axon-mediated neurogenic flare responses to cutaneous heating (LDIFLARE. Area under the curve (AUC and optimal thresholds were determined by receiver operating characteristic (ROC curves in the type 1 diabetes cohort. RESULTS: Type 1 diabetes subjects were 42±17 years of age with mean HbA1c 7.9±1.7%. Fifty-nine (45% met the case definition for DSP. CDT values were lowest in cases with DSP (18.3±8.4°C compared to controls without DSP (28.4±3.5°C and to healthy volunteers (29.6±1.8°C; p-value for both comparisons<0.0001. AUCCDT was 0.863 which was similar to AUCTCNS (0.858, p = 0.24 and AUCHRV (0.788, p = 0.05, but exceeded AUCLDIFLARE (0.750, p = 0.001. The threshold of <25.1°C was equivalent to the lower bound of the healthy volunteer 95% distribution [25.1, 30.8°C] and performed with 83% sensitivity and 82% specificity. CONCLUSIONS: Akin to novel small fiber morphological measures, CDT is a functional test that identifies DSP with very good diagnostic performance. These findings support further research that revisits the role of CDT in early DSP detection.

  19. Lack of evidence for protein AA reactivity in amyloid deposits of lattice corneal dystrophy and amyloid corneal degeneration.

    Science.gov (United States)

    Gorevic, P D; Rodrigues, M M; Krachmer, J H; Green, C; Fujihara, S; Glenner, G G

    1984-08-15

    Amyloid fibrils occurring in primary and myeloma-associated (AL), secondary (AA), and certain neuropathic hereditary forms of systemic amyloidosis can be distinguished biochemically or immunohistologically as being composed of immunoglobulin light chain, protein AA, or prealbumin respectively. All types of systemic and several localized forms of amyloidosis contain amyloid P component (protein AP). We studied formalin-fixed tissue from eight cases of lattice corneal dystrophy by the immunoperoxidase method using antisera to proteins AA and AP, to normal serum prealbumin and prealbumin isolated from a case of hereditary amyloidosis, and to light-chain determinants; additional cases were examined by indirect immunofluorescence of fresh-frozen material. We found weak (1:10 dilution) staining with anti-AP, but no reactivity with other antisera. Congo red staining was resistant to pretreatment of sections with potassium permanganate, a characteristic of non-AA amyloid. Two-dimensional gels of solubilized proteins from frozen tissue from two cases of lattice corneal dystrophy resembled those obtained from normal human cornea. Western blots of two cases of polymorphous amyloid degeneration and solubilized protein from normal cornea did not react with radioactive iodine-labeled anti-AA or anti-AP with purified protein AP and unfixed protein AA amyloid tissue as controls. We were unable to corroborate the presence of protein AA in the amyloid deposits of lattice corneal dystrophy. Although staining with antiserum to protein AP was demonstrable, the molecular configuration of this protein in stromal deposits remains to be defined.

  20. Ubiquilin 1 modulates amyloid precursor protein trafficking and Abeta secretion.

    Science.gov (United States)

    Hiltunen, Mikko; Lu, Alice; Thomas, Anne V; Romano, Donna M; Kim, Minji; Jones, Phill B; Xie, Zhongcong; Kounnas, Maria Z; Wagner, Steven L; Berezovska, Oksana; Hyman, Bradley T; Tesco, Giuseppina; Bertram, Lars; Tanzi, Rudolph E

    2006-10-27

    Ubiquilin 1 (UBQLN1) is a ubiquitin-like protein, which has been shown to play a central role in regulating the proteasomal degradation of various proteins, including the presenilins. We recently reported that DNA variants in UBQLN1 increase the risk for Alzheimer disease, by influencing expression of this gene in brain. Here we present the first assessment of the effects of UBQLN1 on the metabolism of the amyloid precursor protein (APP). For this purpose, we employed RNA interference to down-regulate UBQLN1 in a variety of neuronal and non-neuronal cell lines. We demonstrate that down-regulation of UBQLN1 accelerates the maturation and intracellular trafficking of APP, while not interfering with alpha-, beta-, or gamma-secretase levels or activity. UBQLN1 knockdown increased the ratio of APP mature/immature, increased levels of full-length APP on the cell surface, and enhanced the secretion of sAPP (alpha- and beta-forms). Moreover, UBQLN1 knockdown increased levels of secreted Abeta40 and Abeta42. Finally, employing a fluorescence resonance energy transfer-based assay, we show that UBQLN1 and APP come into close proximity in intact cells, independently of the presence of the presenilins. Collectively, our findings suggest that UBQLN1 may normally serve as a cytoplasmic "gatekeeper" that may control APP trafficking from intracellular compartments to the cell surface. These findings suggest that changes in UBQLN1 steady-state levels affect APP trafficking and processing, thereby influencing the generation of Abeta.

  1. Serum amyloid A in the diagnosis of feline sepsis.

    Science.gov (United States)

    Troìa, Roberta; Gruarin, Marta; Foglia, Armando; Agnoli, Chiara; Dondi, Francesco; Giunti, Massimo

    2017-11-01

    Systemic inflammatory response syndrome (SIRS) and sepsis can be challenging to diagnose in cats. Retrospectively, we investigated the diagnostic and prognostic potential of serum amyloid A (SAA), a major feline acute-phase protein (APP), in a population of critically ill cats with SIRS related to trauma or sepsis. A total of 56 SIRS cats (trauma n = 27; sepsis n = 29) were included and compared with healthy controls ( n = 18). SAA concentration was significantly increased in SIRS cats compared to controls, confirming its potential for the detection of systemic inflammation in this species. Significantly higher values of SAA were detected in cats belonging to the sepsis group; however, according to the results of the receiver operating characteristic curve analysis, the value of using SAA (>81 mg/L) to discriminate septic cats was only moderate (AUC = 0.76). Additionally, cats with sepsis had significantly higher serum bilirubin concentrations and toxic neutrophil changes compared to the trauma group. Overall, 38 of 56 cats were survivors; 18 of 56 were non-survivors, with 83% of the non-survivors (15 of 18) belonging to the sepsis group. Serum bilirubin concentration, but not SAA, was able to predict outcome. Prospective studies are needed to assess the potential of SAA in the diagnosis of feline sepsis and outcome prediction.

  2. Posterior atrophy predicts time to dementia in patients with amyloid-positive mild cognitive impairment.

    Science.gov (United States)

    Pyun, Jung-Min; Park, Young Ho; Kim, Hang-Rai; Suh, Jeewon; Kang, Min Ju; Kim, Beom Joon; Youn, Young Chul; Jang, Jae-Won; Kim, SangYun

    2017-12-16

    In patients with amyloid-positive mild cognitive impairment (MCI), neurodegenerative biomarkers such as medial temporal lobe atrophy (MTA) are useful to predict disease progression to dementia. Although posterior atrophy (PA) is a well-known neurodegenerative biomarker of Alzheimer's disease, little is known about PA as a predictor in patients with amyloid-positive MCI. We included 258 patients with amyloid-positive MCI with at least one follow-up visit, and who had low cerebrospinal fluid (CSF) β-amyloid 1-42 concentration. Data were obtained from the Alzheimer's Disease Neuroimaging Initiative study. We assessed PA and MTA on magnetic resonance imaging (MRI) using visual rating scales and retrospectively determined progression to dementia during the follow-up period of up to 3 years (median 24 months). The Cox proportional hazards model was used to analyze hazard ratios (HRs) of PA and MTA for disease progression. Additionally, subjects were divided into four groups according to brain atrophy pattern (no atrophy, MTA only, PA only, both MTA and PA), and HRs for disease progression were compared with the no atrophy reference group. Analyses were conducted with and without adjustment for CSF phosphorylated tau 181p (p-tau) and baseline demographics. A total of 123 patients (47.7%) showed MTA and 174 patients (67.4%) showed PA. Of the total cohort, 139 cases (53.9%) progressed to dementia. PA and MTA were associated with an increased risk for progression to dementia (HR 2.244, 95% confidence interval (CI) 1.497-3.364, and HR 1.682, 95% CI 1.203-2.352, respectively). In the analysis according to atrophy pattern, HR (95% CI) for progression was 2.998 (1.443-6.227) in the MTA only group, 3.126 (1.666-5.864) in the PA only group, and 3.814 (2.045-7.110) in both MTA and PA group. These results remained significant after adjustment. In patients with amyloid-positive MCI, PA could predict progression to dementia independently of MTA.

  3. TDP-43 inclusion bodies formed in bacteria are structurally amorphous, non-amyloid and inherently toxic to neuroblastoma cells.

    Directory of Open Access Journals (Sweden)

    Claudia Capitini

    Full Text Available Accumulation of ubiquitin-positive, tau- and α-synuclein-negative intracellular inclusions of TDP-43 in the central nervous system represents the major hallmark correlated to amyotrophic lateral sclerosis and frontotemporal lobar degeneration with ubiquitin-positive inclusions. Such inclusions have variably been described as amorphous aggregates or more structured deposits having an amyloid structure. Following the observations that bacterial inclusion bodies generally consist of amyloid aggregates, we have overexpressed full-length TDP-43 and C-terminal TDP-43 in E. coli, purified the resulting full-length and C-terminal TDP-43 containing inclusion bodies (FL and Ct TDP-43 IBs and subjected them to biophysical analyses to assess their structure/morphology. We show that both FL and Ct TDP-43 aggregates contained in the bacterial IBs do not bind amyloid dyes such as thioflavin T and Congo red, possess a disordered secondary structure, as inferred using circular dichroism and infrared spectroscopies, and are susceptible to proteinase K digestion, thus possessing none of the hallmarks for amyloid. Moreover, atomic force microscopy revealed an irregular structure for both types of TDP-43 IBs and confirmed the absence of amyloid-like species after proteinase K treatment. Cell biology experiments showed that FL TDP-43 IBs were able to impair the viability of cultured neuroblastoma cells when added to their extracellular medium and, more markedly, when transfected into their cytosol, where they are at least in part ubiquitinated and phosphorylated. These data reveal an inherently high propensity of TDP-43 to form amorphous aggregates, which possess, however, an inherently high ability to cause cell dysfunction. This indicates that a gain of toxic function caused by TDP-43 deposits is effective in TDP-43 pathologies, in addition to possible loss of function mechanisms originating from the cellular mistrafficking of the protein.

  4. Early enriched environment exposure protects spatial memory and accelerates amyloid plaque formation in APP(Swe/PS1(L166P mice.

    Directory of Open Access Journals (Sweden)

    Francesca Montarolo

    Full Text Available Enriched environment exposure improves several aspects of cognitive performance in Alzheimer's disease patients and in animal models and, although the role of amyloid plaques is questionable, several studies also assessed their response to enriched environment, with contrasting results. Here we report that rearing APP(Swe/PS1(L166P mice in an enriched environment since birth rescued the spatial memory impairment otherwise present at 6 months of age. At the same time, the exposure to the enriched environment caused a transient acceleration of plaque formation, while there was no effect on intracellular staining with the 6E10 antibody, which recognizes β-amyloid, full length amyloid precursor protein and its C-terminal fragments. The anticipation of plaque formation required exposure during early development, suggesting an action within critical periods for circuits formation. On the other hand, chronic neuronal activity suppression by tetrodotoxin decreased the number of plaques without affecting intracellular amyloid. These results indicate that enriched environment exposure since early life has a protective effect on cognitive deterioration although transiently accelerates amyloid deposition. In addition, the effects of the enriched environment might be due to increased neuronal activity, because plaques were reduced by suppression of electrical signaling by tetrodotoxin.

  5. Dietary fish oil, and to a lesser extent the fat-1 transgene, increases astrocyte activation in response to intracerebroventricular amyloid-β 1-40 in mice.

    Science.gov (United States)

    Hopperton, Kathryn E; James, Nicholas C E; Mohammad, Dana; Irfan, Maha; Bazinet, Richard P

    2017-11-07

    Increases in astrocytes and one of their markers, glial fibrillary acidic protein (GFAP) have been reported in the brains of patients with Alzheimer's disease (AD). N-3 polyunsaturated fatty acids (PUFA) modulate neuroinflammation in animal models; however, their effect on astrocytes is unclear. Fat-1 mice and their wildtype littermates were fed either a fish oil diet or a safflower oil diet deprived of n-3 PUFA. At 12 weeks, mice underwent intracerebroventricular infusion of amyloid-β 1-40. Astrocyte phenotype in the hippocampus was assessed at baseline and 10 days post-surgery using immunohistochemistry with various microscopy and image analysis techniques. GFAP increased in all groups in response to amyloid-β, with a greater increase in fish oil-fed mice than either fat-1 or wildtype safflower oil-fed mice. Astrocytes in this group were also more hypertrophic, suggesting increased activation. Both fat-1- and fish oil-fed mice had greater increases in branch number and length in response to amyloid-β infusion than wildtype safflower animals. Fish oil feeding, and to a lesser extent the fat-1 transgene, enhances the astrocyte activation phenotype in response to amyloid-β 1-40. Astrocytes in mice fed fish oil were more activated in response to amyloid-β than in fat-1 mice despite similar levels of hippocampal n-3 PUFA, which suggests that other fatty acids or dietary factors contribute to this effect.

  6. Nonequilibrium and generalized-ensemble molecular dynamics simulations for amyloid fibril

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Hisashi [Research Center for Computational Science, Institute for Molecular Science, Okazaki, Aichi 444-8585 (Japan); Department of Structural Molecular Science, The Graduate University for Advanced Studies, Okazaki, Aichi 444-8585 (Japan)

    2015-12-31

    Amyloids are insoluble and misfolded fibrous protein aggregates and associated with more than 20 serious human diseases. We perform all-atom molecular dynamics simulations of amyloid fibril assembly and disassembly.

  7. Identification of a Common Binding Mode for Imaging Agents to Amyloid Fibrils from Molecular Dynamics Simulations

    DEFF Research Database (Denmark)

    Skeby, Katrine Kirkeby; Sørensen, Jesper; Schiøtt, Birgit

    2013-01-01

    Amyloid diseases are characterized by the misfolding and deposition of proteins in the body in the form of insoluble amyloid fibrils. Alzheimer’s disease and type 2 diabetes mellitus are two examples of amyloid diseases which are closely related both with respect to the atomic structures of the a...... binding modes for imaging agents is proposed to originate from subtle differences in amino acid composition of the surface grooves on an amyloid fibril, resulting in fine tuning of the binding affinities for a specific amyloid fibril....... experimentally due to the insoluble nature of amyloid fibrils. This study uses molecular dynamics simulations to investigate the interactions between 13 aromatic amyloid imaging agents, entailing 4 different organic scaffolds, and a model of an amyloid fibril. Clustering analysis combined with free energy...

  8. Key aromatic/hydrophobic amino acids controlling a cross-amyloid peptide interaction versus amyloid self-assembly.

    Science.gov (United States)

    Bakou, Maria; Hille, Kathleen; Kracklauer, Michael; Spanopoulou, Anna; Frost, Christina V; Malideli, Eleni; Yan, Li-Mei; Caporale, Andrea; Zacharias, Martin; Kapurniotu, Aphrodite

    2017-09-01

    The interaction of the intrinsically disordered polypeptide islet amyloid polypeptide (IAPP), which is associated with type 2 diabetes (T2D), with the Alzheimer's disease amyloid-β (Aβ) peptide modulates their self-assembly into amyloid fibrils and may link the pathogeneses of these two cell-degenerative diseases. However, the molecular determinants of this interaction remain elusive. Using a systematic alanine scan approach, fluorescence spectroscopy, and other biophysical methods, including heterocomplex pulldown assays, far-UV CD spectroscopy, the thioflavin T binding assay, transmission EM, and molecular dynamics simulations, here we identified single aromatic/hydrophobic residues within the amyloid core IAPP region as hot spots or key residues of its cross-interaction with Aβ40(42) peptide. Importantly, we also find that none of these residues in isolation plays a key role in IAPP self-assembly, whereas simultaneous substitution of four aromatic/hydrophobic residues with Ala dramatically impairs both IAPP self-assembly and hetero-assembly with Aβ40(42). Furthermore, our experiments yielded several novel IAPP analogs, whose sequences are highly similar to that of IAPP but have distinct amyloid self- or cross-interaction potentials. The identified similarities and major differences controlling IAPP cross-peptide interaction with Aβ40(42) versus its amyloid self-assembly offer a molecular basis for understanding the underlying mechanisms. We propose that these insights will aid in designing intervention strategies and novel IAPP analogs for the management of type 2 diabetes, Alzheimer's disease, or other diseases related to IAPP dysfunction or cross-amyloid interactions. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Phenolsulfonphthalein, but not phenolphthalein, inhibits amyloid fibril formation: implications for the modulation of amyloid self-assembly.

    Science.gov (United States)

    Levy, Michal; Porat, Yair; Bacharach, Eran; Shalev, Deborah E; Gazit, Ehud

    2008-06-03

    The study of the mechanism of amyloid fibril formation and its inhibition is of key medical importance due to the lack of amyloid assembly inhibitors that are approved for clinical use. We have previously demonstrated the potent inhibitory potential of phenolsulfonphthalein, a nontoxic compound that was approved for diagnostic use in human subjects, on aggregation of islet amyloid polypeptide (IAPP) that is associated with type 2 diabetes. Here, we extend our studies on the mechanism of action of phenolsulfonphthalein by comparing its antiamyloidogenic effect to a very similar compound that is also approved for human use, phenolphthalein. While these compounds have very similar primary chemical structures, they significantly differ in their three-dimensional conformation. Our results clearly demonstrated that these two compounds had completely different inhibitory potencies: While phenolsulfonphthalein was a very potent inhibitor of amyloid fibril formation by IAPP, phenolphthalein did not show significant antiamyloidogenic activity. This behavior was observed with a short amyloid fragment of IAPP and also with the full-length polypeptide. The NMR spectrum of IAPP 20-29 in the presence of phenolsulfonphthalein showed chemical shift deviations that were different from the unbound or phenolphthalein-bound peptide. Differential activity was also observed in the inhibition of insulin amyloid formation by these two compounds, and density-gradient experiments clearly demonstrated the different inhibitory effect of the two compounds on the formation of prefibrillar assemblies. Taken together, our studies suggest that the three-dimensional arrangement of the polyphenol phenolsulfonphthalein has a central role in its amyloid formation inhibition activity.

  10. Subcutaneous immunoglobulin as first-line therapy in treatment-naive patients with chronic inflammatory demyelinating polyneuropathy

    DEFF Research Database (Denmark)

    Markvardsen, L. H.; Sindrup, S. H.; Christiansen, I.

    2017-01-01

    Background and purpose: Subcutaneous immunoglobulin (SCIG) is effective as maintenance treatment in chronic inflammatory demyelinating polyneuropathy (CIDP). We investigated whether multiple subcutaneous infusions are as effective as conventional therapy with intravenous loading doses in treatment...... treatment arm and followed for a further 10 weeks. All participants were evaluated at weeks 0, 2, 5 and 10 during both therapies. Primary outcome was combined isokinetic muscle strength (cIKS). Secondary outcomes were disability, clinical evaluation of muscle strength and the performance of various function...... tests. Results: All participants received both therapies, 14 completing the protocol. Overall, cIKS increased by 7.4 ± 14.5% (P = 0.0003) during SCIG and by 6.9 ± 16.8% (P = 0.002) during IVIG, the effect being similar (P = 0.80). Improvement of cIKS peaked 2 weeks after IVIG and 5 weeks after SCIG...

  11. Understanding the Disease Course and Therapeutic Benefit of Tafamidis Across Real-World Studies of Hereditary Transthyretin Amyloidosis with Polyneuropathy: A Proof of Concept for Integrative Data Analytic Approaches.

    Science.gov (United States)

    Serrano, Daniel; Atzinger, Christopher B; Botteman, Marc F

    2018-04-02

    Hereditary transthyretin (TTR) amyloidosis with polyneuropathy (hATTR-PN) is a rare, autosomal dominant amyloidosis characterized primarily by progressive ascending sensorimotor neuropathy often associated with  autonomic involvement. hATTR-PN is caused by a mutation in the TTR gene leading to protein misfolding and amyloid accumulation in peripheral nerves and vital organs. The latest global prevalence estimates point to 10,000 cases worldwide, with an upper end of about 40,000. Tafamidis has been approved in over 40 countries for delaying neurologic disease progression in early-stage hATTR-PN. Multiple observational studies have examined clinical outcomes in hATTR-PN patients treated with tafamidis in the routine clinical setting. Integrative data analysis (IDA) is a technique for optimally constructing synthetic treatment and control cohorts from multiple independent studies, which allows meta-analysis of patient-level data. Herein, we provide a proof of concept for the application of IDA to real-world and natural history hATTR-PN data. IDA permits increased understanding of outcomes in tafamidis-treated and untreated persons with hATTR-PN by optimally pooling all available information. Summary statistics corresponding to the Neuropathy Impairment Score-Lower Limb (NIS-LL) from five published studies were pooled, converted to change from baseline means and variances, and analyzed using IDA. IDA-based synthetic cohorts were generated by averaging across studies stratified on treatment versus control cohort. Trends in change from baseline in each study and the corresponding synthetic cohorts were plotted. Patient-level data were simulated from the synthetic cohort trends in a Monte Carlo simulation to highlight the ability to contrast synthetic cohort trends using the mixed model for repeated measures (MMRM). The average sample size among the five studies was 71 (37-128) patients. The average NIS-LL trends indicated that tafamidis-treated patients experienced

  12. Amyloid Structure and Assembly: Insights from Scanning Transmission Electron Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Goldsbury, C.; Wall, J.; Baxa, U.; Simon, M. N.; Steven, A. C.; Engel, A.; Aebi, U.; Muller, S. A.

    2011-01-01

    Amyloid fibrils are filamentous protein aggregates implicated in several common diseases such as Alzheimer's disease and type II diabetes. Similar structures are also the molecular principle of the infectious spongiform encephalopathies such as Creutzfeldt-Jakob disease in humans, scrapie in sheep, and of the so-called yeast prions, inherited non-chromosomal elements found in yeast and fungi. Scanning transmission electron microscopy (STEM) is often used to delineate the assembly mechanism and structural properties of amyloid aggregates. In this review we consider specifically contributions and limitations of STEM for the investigation of amyloid assembly pathways, fibril polymorphisms and structural models of amyloid fibrils. This type of microscopy provides the only method to directly measure the mass-per-length (MPL) of individual filaments. Made on both in vitro assembled and ex vivo samples, STEM mass measurements have illuminated the hierarchical relationships between amyloid fibrils and revealed that polymorphic fibrils and various globular oligomers can assemble simultaneously from a single polypeptide. The MPLs also impose strong constraints on possible packing schemes, assisting in molecular model building when combined with high-resolution methods like solid-state nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR).

  13. New Insights in the Amyloid-Beta Interaction with Mitochondria

    Directory of Open Access Journals (Sweden)

    Carlos Spuch

    2012-01-01

    Full Text Available Biochemical and morphological alterations of mitochondria may play an important role in the pathogenesis of Alzheimer’s disease (AD. Particularly, mitochondrial dysfunction is a hallmark of amyloid-beta-induced neuronal toxicity in Alzheimer’s disease. The recent emphasis on the intracellular biology of amyloid-beta and its precursor protein (APP has led researchers to consider the possibility that mitochondria-associated and mitochondrial amyloid-beta may directly cause neurotoxicity. Both proteins are known to localize to mitochondrial membranes, block the transport of nuclear-encoded mitochondrial proteins to mitochondria, interact with mitochondrial proteins, disrupt the electron transport chain, increase reactive oxygen species production, cause mitochondrial damage, and prevent neurons from functioning normally. In this paper, we will outline current knowledge of the intracellular localization of amyloid-beta. Moreover, we summarize evidence from AD postmortem brain as well as animal AD models showing that amyloid-beta triggers mitochondrial dysfunction through a number of pathways such as impairment of oxidative phosphorylation, elevation of reactive oxygen species production, alteration of mitochondrial dynamics, and interaction with mitochondrial proteins. Thus, this paper supports the Alzheimer cascade mitochondrial hypothesis such as the most important early events in this disease, and probably one of the future strategies on the therapy of this neurodegenerative disease.

  14. Intracellular tracing of amyloid vaccines through direct fluorescent labelling.

    Science.gov (United States)

    Mold, Matthew; Kumar, Manpreet; Mirza, Ambreen; Shardlow, Emma; Exley, Christopher

    2018-02-05

    Alzheimer's disease is a debilitating neurodegenerative condition that progressively causes synaptic loss and major neuronal damage. Immunotherapy utilising Aβ as an active immunogen or via passive treatment utilising antibodies raised to amyloid have shown therapeutic promise. The migratory properties of peripheral blood-borne monocytes and their ability to enter the central nervous system, suggests a beneficial role in mediating tissue damage and neuroinflammation. However, the intrinsic phagocytic properties of such cells have pre-disposed them to internalise misfolded amyloidogenic peptides that could act as seeds capable of nucleating amyloid formation in the brain. Mechanisms governing the cellular fate of amyloid therefore, may prove to be key in the development of future vaccination regimes. Herein, we have developed unequivocal and direct conformation-sensitive fluorescent molecular probes that reveal the intracytoplasmic and intranuclear persistence of amyloid in a monocytic T helper 1 (THP-1) cell line. Use of the pathogenic Aβ 42 species as a model antigen in simulated vaccine formulations suggested differing mechanisms of cellular internalisation, in which fibrillar amyloid evaded lysosomal capture, even when co-deposited on particulate adjuvant materials. Taken collectively, direct fluorescent labelling of antigen-adjuvant complexes may serve as critical tools in understanding subsequent immunopotentiation in vaccines directed against amyloidosis and wider dementia.

  15. Amylin under examination. Fibrillogenic polypeptide of pancreatic amyloid

    Directory of Open Access Journals (Sweden)

    Małgorzata Marszałek

    2015-06-01

    Full Text Available In patients or animals affected by 2 type diabetes mellitus (diabetes mellitus type 2, DM2, non-insulin-dependent diabetes mellitus, NIDDM or pancreatic tumor disease e.g., insulinoma, some pathological deposits, called amyloid, are observed among cells of islets of Langerhans. Among other constituents, pancreatic deposits consist of an insoluble, fibrillar form of peptide neurohormone termed amylin, produced by pancreatic beta cells. It is thought that formation of fibrillar deposits of misfolded and aggregated peptide is highly toxic to beta cells and leads to cell dysfunction, cell loss, pancreas destruction and progress of the disease. This relatively small, 37-amino acid peptide constitutes a serious scientific, research and to some extent a medical problem. This article presents amylin as a fibrillating molecule which participates in formation of amyloid deposits in human and animal pancreas, Langerhans islets as a microenvironment of pancreatic amyloid formation, occurrence of amylin and amyloid in animals and humans, and physico-chemical requirements to meet to name amylin deposit as amyloid.

  16. Imaging and quantification of amyloid fibrillation in the cell nucleus.

    Science.gov (United States)

    Arnhold, Florian; Scharf, Andrea; von Mikecz, Anna

    2015-01-01

    Xenobiotics, as well as intrinsic processes such as cellular aging, contribute to an environment that constantly challenges nuclear organization and function. While it becomes increasingly clear that proteasome-dependent proteolysis is a major player, the topology and molecular mechanisms of nuclear protein homeostasis remain largely unknown. We have shown previously that (1) proteasome-dependent protein degradation is organized in focal microenvironments throughout the nucleoplasm and (2) heavy metals as well as nanoparticles induce nuclear protein fibrillation with amyloid characteristics. Here, we describe methods to characterize the landscape of intranuclear amyloid on the global and local level in different systems such as cultures of mammalian cells and the soil nematode Caenorhabditis elegans. Application of discrete mathematics to imaging data is introduced as a tool to develop pattern recognition of intracellular protein fibrillation. Since stepwise fibrillation of otherwise soluble proteins to insoluble amyloid-like protein aggregates is a hallmark of neurodegenerative protein-misfolding disorders including Alzheimer's disease, CAG repeat diseases, and the prion encephalopathies, investigation of intracellular amyloid may likewise aid to a better understanding of the pathomechanisms involved. We consider aggregate profiling as an important experimental approach to determine if nuclear amyloid has toxic or protective roles in various disease processes.

  17. The effect of tachykinin neuropeptides on amyloid {beta} aggregation

    Energy Technology Data Exchange (ETDEWEB)

    Flashner, Efrat [The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904 (Israel); Raviv, Uri, E-mail: raviv@chem.ch.huji.ac.il [The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904 (Israel); Friedler, Assaf, E-mail: assaf@chem.ch.huji.ac.il [The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 91904 (Israel)

    2011-04-01

    Research highlights: {yields} Mechanistic explanation of how tachykinin neuropeptides reduce A{beta}-induced neurotoxicity. {yields} Biophysical studies suggest that tachykinins do not modulate the distribution of A{beta} oligomeric states, but rather may incorporate into the fibrils. {yields} A possible strategy to inhibit toxicity of amyloid fibrils. -- Abstract: A hallmark of Alzheimer's disease is production of amyloid {beta} peptides resulting from aberrant cleavage of the amyloid precursor protein. Amyloid {beta} assembles into fibrils under physiological conditions, through formation of neurotoxic intermediate oligomers. Tachykinin peptides are known to affect amyloid {beta} neurotoxicity in cells. To understand the mechanism of this effect, we studied how tachykinins affect A{beta}(1-40) aggregation in vitro. Fibrils grown in the presence of tachykinins exhibited reduced thioflavin T (ThT) fluorescence, while their morphology, observed in transmission electron microscopy (TEM), did not alter. Cross linking studies revealed that the distribution of low molecular weight species was not affected by tachykinins. Our results suggest that there may be a specific interaction between tachykinins and A{beta}(1-40) that allows them to co-assemble. This effect may explain the reduction of A{beta}(1-40) neurotoxicity in cells treated with tachykinins.

  18. An ARHGEF10 deletion is highly associated with a juvenile-onset inherited polyneuropathy in Leonberger and Saint Bernard dogs.

    Directory of Open Access Journals (Sweden)

    Kari J Ekenstedt

    2014-10-01

    Full Text Available An inherited polyneuropathy (PN observed in Leonberger dogs has clinical similarities to a genetically heterogeneous group of peripheral neuropathies termed Charcot-Marie-Tooth (CMT disease in humans. The Leonberger disorder is a severe, juvenile-onset, chronic, progressive, and mixed PN, characterized by exercise intolerance, gait abnormalities and muscle atrophy of the pelvic limbs, as well as inspiratory stridor and dyspnea. We mapped a PN locus in Leonbergers to a 250 kb region on canine chromosome 16 (Praw = 1.16×10-10, Pgenome, corrected = 0.006 utilizing a high-density SNP array. Within this interval is the ARHGEF10 gene, a member of the rho family of GTPases known to be involved in neuronal growth and axonal migration, and implicated in human hypomyelination. ARHGEF10 sequencing identified a 10 bp deletion in affected dogs that removes four nucleotides from the 3'-end of exon 17 and six nucleotides from the 5'-end of intron 17 (c.1955_1958+6delCACGGTGAGC. This eliminates the 3'-splice junction of exon 17, creates an alternate splice site immediately downstream in which the processed mRNA contains a frame shift, and generates a premature stop codon predicted to truncate approximately 50% of the protein. Homozygosity for the deletion was highly associated with the severe juvenile-onset PN phenotype in both Leonberger and Saint Bernard dogs. The overall clinical picture of PN in these breeds, and the effects of sex and heterozygosity of the ARHGEF10 deletion, are less clear due to the likely presence of other forms of PN with variable ages of onset and severity of clinical signs. This is the first documented severe polyneuropathy associated with a mutation in ARHGEF10 in any species.

  19. Cerebrospinal Fluid Amyloid Beta and Tau Concentrations Are Not Modulated by 16 Weeks of Moderate- to High-Intensity Physical Exercise in Patients with Alzheimer Disease

    DEFF Research Database (Denmark)

    Jensen, Camilla Steen; Portelius, Erik; Siersma, Volkert

    2016-01-01

    Background: Physical exercise may have some effect on cognition in patients with Alzheimer disease (AD). However, the underlying biochemical effects are unclear. Animal studies have shown that amyloid beta (Aβ), one of the pathological hallmarks of AD, can be altered with high levels of physical...... of Life, Physical Health and Functional Ability in Alzheimer's Disease: The Effect of Physical Exercise (ADEX) study we analyzed cerebrospinal fluid samples for Aβ species, total tau (t-tau), phosphorylated tau (p-tau) and soluble amyloid precursor protein (sAPP) species. We also assessed the patients...

  20. Whole body amyloid deposition imaging by 123I-SAP scintigraphy

    NARCIS (Netherlands)

    van Rheenen, Ronald; Glaudemans, Andor; Hazenberg, Bouke

    2011-01-01

    Amyloidosis is the name of a group of diseases characterized by extracellular deposition of amyloid fibrils. Deposition of amyloid can be localized or systemic. The 123I-SAP-scan can be used to image extent and distribution of amyloid deposition in patients with systemic AA, AL and ATTR amyloidosis.

  1. Trifluoroethanol modulates α-synuclein amyloid-like aggregate formation, stability and dissolution

    DEFF Research Database (Denmark)

    Di Carlo, Maria Giovanna; Vetri, Valeria; Buscarino, Gianpiero

    2016-01-01

    The conversion of proteins into amyloid fibrils and other amyloid-like aggregates is closely connected to the onset of a series of age-related pathologies. Upon changes in environmental conditions, amyloid-like aggregates may also undergo disassembly into oligomeric aggregates, the latter being r...

  2. Analysis of amyloid fibrils in the cheetah (Acinonyx jubatus).

    Science.gov (United States)

    Bergström, Joakim; Ueda, Mitsuharu; Une, Yumi; Sun, Xuguo; Misumi, Shogo; Shoji, Shozo; Ando, Yukio

    2006-06-01

    Recently, a high prevalence of amyloid A (AA) amyloidosis has been documented among captive cheetahs worldwide. Biochemical analysis of amyloid fibrils extracted from the liver of a Japanese captive cheetah unequivocally showed that protein AA was the main fibril constituent. Further characterization of the AA fibril components by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis revealed three main protein AA bands with approximate molecular weights of 8, 10 and 12 kDa. Mass spectrometry analysis of the 12-kDa component observed in SDS-PAGE and Western blotting confirmed the molecular weight of a 12,381-Da peak. Our finding of a 12-kDa protein AA component provides evidence that the cheetah SAA sequence is longer than the previously reported 90 amino acid residues (approximately 10 kDa), and hence SAA is part of the amyloid fibril.

  3. Amyloid cascade hypothesis: Pathogenesis and therapeutic strategies in Alzheimer's disease.

    Science.gov (United States)

    Barage, Sagar H; Sonawane, Kailas D

    2015-08-01

    Alzheimer's disease is an irreversible, progressive neurodegenerative disorder. Various therapeutic approaches are being used to improve the cholinergic neurotransmission, but their role in AD pathogenesis is still unknown. Although, an increase in tau protein concentration in CSF has been described in AD, but several issues remains unclear. Extensive and accurate analysis of CSF could be helpful to define presence of tau proteins in physiological conditions, or released during the progression of neurodegenerative disease. The amyloid cascade hypothesis postulates that the neurodegeneration in AD caused by abnormal accumulation of amyloid beta (Aβ) plaques in various areas of the brain. The amyloid hypothesis has continued to gain support over the last two decades, particularly from genetic studies. Therefore, current research progress in several areas of therapies shall provide an effective treatment to cure this devastating disease. This review critically evaluates general biochemical and physiological functions of Aβ directed therapeutics and their relevance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Destroying activity of magnetoferritin on lysozyme amyloid fibrils

    Energy Technology Data Exchange (ETDEWEB)

    Kopcansky, Peter; Siposova, Katarina [Institute of Experimental Physics, SAS, Watsonova 47, 040 01 Kosice (Slovakia); Melnikova, Lucia, E-mail: melnikova@saske.sk [Institute of Experimental Physics, SAS, Watsonova 47, 040 01 Kosice (Slovakia); Bednarikova, Zuzana [Institute of Experimental Physics, SAS, Watsonova 47, 040 01 Kosice (Slovakia); Institute of Chemical Sciences, Faculty of Sciences, Safarik University, Kosice (Slovakia); Timko, Milan; Mitroova, Zuzana; Antosova, Andrea [Institute of Experimental Physics, SAS, Watsonova 47, 040 01 Kosice (Slovakia); Garamus, Vasil M. [Helmholtz-Zentrum Geesthacht: Centre for Materials and Coastal Research, Max-Planck-Street 1, 21502 Geesthacht (Germany); Petrenko, Viktor I. [Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, 141980 Moscow Region (Russian Federation); Kyiv Taras Shevchenko National University, Volodymyrska Street 64, Kyiv 01033 (Ukraine); Avdeev, Mikhail V. [Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, 141980 Moscow Region (Russian Federation); Gazova, Zuzana [Institute of Experimental Physics, SAS, Watsonova 47, 040 01 Kosice (Slovakia); Department of Medical and Clinical Biochemistry and LABMED, Tr. SNP 1, 040 11 Kosice (Slovakia)

    2015-03-01

    Presence of protein amyloid aggregates (oligomers, protofilaments, fibrils) is associated with many diseases as diabetes mellitus or Alzheimer's disease. The interaction between lysozyme amyloid fibrils and magnetoferritin loaded with different amount of iron atoms (168 or 532 atoms) has been investigated by small-angle X-rays scattering and thioflavin T fluorescence measurements. Results suggest that magnetoferritin caused an iron atom-concentration dependent reduction of lysozyme fibril size. - Highlights: • The interaction between lysozyme amyloid fibrils and magnetoferritin loaded with different amount of iron atoms (168 or 532 atoms) has been investigated by small-angle X-rays scattering and thioflavin T fluorescence measurements. • Results suggest that magnetoferritin caused an iron atom-concentration dependent reduction of lysozyme fibril size.

  5. Alzheimer's disease: the amyloid hypothesis and the Inverse Warburg effect

    KAUST Repository

    Demetrius, Lloyd A.

    2015-01-14

    Epidemiological and biochemical studies show that the sporadic forms of Alzheimer\\'s disease (AD) are characterized by the following hallmarks: (a) An exponential increase with age; (b) Selective neuronal vulnerability; (c) Inverse cancer comorbidity. The present article appeals to these hallmarks to evaluate and contrast two competing models of AD: the amyloid hypothesis (a neuron-centric mechanism) and the Inverse Warburg hypothesis (a neuron-astrocytic mechanism). We show that these three hallmarks of AD conflict with the amyloid hypothesis, but are consistent with the Inverse Warburg hypothesis, a bioenergetic model which postulates that AD is the result of a cascade of three events—mitochondrial dysregulation, metabolic reprogramming (the Inverse Warburg effect), and natural selection. We also provide an explanation for the failures of the clinical trials based on amyloid immunization, and we propose a new class of therapeutic strategies consistent with the neuroenergetic selection model.

  6. Radiological findings of amyloid arthropathy in long-term haemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Rios Camacho, C. [Dept. of Nephrology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Talegon Melendez, A. [Dept. of Radiology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Valenzuela, A. [Dept. of Rheumatology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Gonzalez Guirao, M. [Dept. of Radiology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Gomez Benitez, S. [Dept. of Radiology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Gil, L. [Dept. of Nephrology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain); Palma Alvarez, A. [Dept. of Nephrology, Hospital Universitario ``Virgen Macarena``, Sevilla (Spain); Mateos Aguilar, J. [Dept. of Nephrology, Hospital Universitario ``Virgen del Rocio``, Sevilla (Spain)

    1992-08-01

    Radiological features of cystic lesions due to beta-2-microglobulin-related amyloidosis have been studied in 88 patients receiving haemodialysis for more than 4 years. Amyloid arthropathy was confirmed by demonstration of amyloid-beta-2-microglobulin deposition on different substrates. Plain radiographs of shoulder, spine, pelvis, hands and knees revealed cystic lesions in 31 patients (35.2%), the distribution being: 71% shoulder, 56.7% carpal bones, 25.8% pelvis, 16.5% femur and 13.3% knees. Discitis was found in 34 patients (38.6%). The ocurrence of geodes was frequent in patients suffering from amyloid arthropathy (63% vs. 23%, P = 0.0001). No significant differences were found in the frequency of discitis or erosive arthropathy in the hands of both groups. The former was related to age and the latter to secondary hyperparathyroidism. We stress the radiographic appearance and the high incidence of these lesions in patients on long-term haemodialysis. (orig.)

  7. Perforin Promotes Amyloid Beta Internalisation in Neurons.

    Science.gov (United States)

    Lana, Erica; Khanbolouki, Mahbod; Degavre, Charline; Samuelsson, Eva-Britt; Åkesson, Elisabet; Winblad, Bengt; Alici, Evren; Lithner, Christina Unger; Behbahani, Homira

    2017-03-01

    Studies on the mechanisms of neuronal amyloid-β (Aβ) internalisation are crucial for understanding the neuropathological progression of Alzheimer's disease (AD). We here investigated how extracellular Aβ peptides are internalised and focused on three different pathways: (i) via endocytic mechanisms, (ii) via the receptor for advanced glycation end products (RAGE) and (iii) via the pore-forming protein perforin. Both Aβ 40 and Aβ 42 were internalised in retinoic acid differentiated neuroblastoma (RA-SH-SY5Y) cells. A higher concentration was required for Aβ 40 (250 nM) compared with Aβ 42 (100 nM). The internalised Aβ 40 showed a dot-like pattern of distribution whereas Aβ 42 accumulated in larger and distinct formations. By confocal microscopy, we showed that Aβ 40 and Aβ 42 co-localised with mitochondria, endoplasmic reticulum (ER) and lysosomes. Aβ treatment of human primary cortical neurons (hPCN) confirmed our findings in RA-SH-SY5Y cells, but hPCN were less sensitive to Aβ; therefore, a 20 (Aβ 40 ) and 50 (Aβ 42 ) times higher concentration was needed for inducing uptake. The blocking of endocytosis completely inhibited the internalisation of Aβ peptides in RA-SH-SY5Y cells and hPCN, indicating that this is a major pathway by which Aβ enters the cells. In addition, the internalisation of Aβ 42 , but not Aβ 40 , was reduced by 55 % by blocking RAGE. Finally, for the first time we showed that pore formation in cell membranes by perforin led to Aβ internalisation in hPCN. Understanding how Aβ is internalised sheds light on the pathological role of Aβ and provides further ideas of inhibitory strategies for preventing Aβ internalisation and the spreading of neurodegeneration in AD.

  8. Structural origin of polymorphism of Alzheimer's amyloid β-fibrils.

    Science.gov (United States)

    Agopian, Audrey; Guo, Zhefeng

    2012-10-01

    Formation of senile plaques containing amyloid fibrils of Aβ (amyloid β-peptide) is a pathological hallmark of Alzheimer's disease. Unlike globular proteins, which fold into unique structures, the fibrils of Aβ and other amyloid proteins often contain multiple polymorphs. Polymorphism of amyloid fibrils leads to different toxicity in amyloid diseases and may be the basis for prion strains, but the structural origin for fibril polymorphism is still elusive. In the present study we investigate the structural origin of two major fibril polymorphs of Aβ40: an untwisted polymorph formed under agitated conditions and a twisted polymorph formed under quiescent conditions. Using electron paramagnetic resonance spectroscopy, we studied the inter-strand side-chain interactions at 14 spin-labelled positions in the Aβ40 sequence. The results of the present study show that the agitated fibrils have stronger inter-strand spin-spin interactions at most of the residue positions investigated. The two hydrophobic regions at residues 17-20 and 31-36 have the strongest interactions in agitated fibrils. Distance estimates on the basis of the spin exchange frequencies suggest that inter-strand distances at residues 17, 20, 32, 34 and 36 in agitated fibrils are approximately 0.2 Å (1 Å=0.1 nm) closer than in quiescent fibrils. We propose that the strength of inter-strand side-chain interactions determines the degree of β-sheet twist, which then leads to the different association patterns between different cross β-units and thus distinct fibril morphologies. Therefore the inter-strand side-chain interaction may be a structural origin for fibril polymorphism in Aβ and other amyloid proteins.

  9. BETASCAN: probable beta-amyloids identified by pairwise probabilistic analysis.

    Directory of Open Access Journals (Sweden)

    Allen W Bryan

    2009-03-01

    Full Text Available Amyloids and prion proteins are clinically and biologically important beta-structures, whose supersecondary structures are difficult to determine by standard experimental or computational means. In addition, significant conformational heterogeneity is known or suspected to exist in many amyloid fibrils. Recent work has indicated the utility of pairwise probabilistic statistics in beta-structure prediction. We develop here a new strategy for beta-structure prediction, emphasizing the determination of beta-strands and pairs of beta-strands as fundamental units of beta-structure. Our program, BETASCAN, calculates likelihood scores for potential beta-strands and strand-pairs based on correlations observed in parallel beta-sheets. The program then determines the strands and pairs with the greatest local likelihood for all of the sequence's potential beta-structures. BETASCAN suggests multiple alternate folding patterns and assigns relative a priori probabilities based solely on amino acid sequence, probability tables, and pre-chosen parameters. The algorithm compares favorably with the results of previous algorithms (BETAPRO, PASTA, SALSA, TANGO, and Zyggregator in beta-structure prediction and amyloid propensity prediction. Accurate prediction is demonstrated for experimentally determined amyloid beta-structures, for a set of known beta-aggregates, and for the parallel beta-strands of beta-helices, amyloid-like globular proteins. BETASCAN is able both to detect beta-strands with higher sensitivity and to detect the edges of beta-strands in a richly beta-like sequence. For two proteins (Abeta and Het-s, there exist multiple sets of experimental data implying contradictory structures; BETASCAN is able to detect each competing structure as a potential structure variant. The ability to correlate multiple alternate beta-structures to experiment opens the possibility of computational investigation of prion strains and structural heterogeneity of amyloid

  10. Native human serum amyloid P component is a single pentamer

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH

    1995-01-01

    Serum amyloid P component (SAP) and C-reactive protein (CRP) are members of the pentraxin protein family. SAP is the precursor protein to amyloid P component present in all forms of amyloidosis. The prevailing notion is that SAP in circulation has the form of a double pentameric molecule (decamer...... by rocket immunoelectrophoresis and electron microscopy. Thus, electron micrographs of purified SAP showed a predominance of decamers. However, the decamer form of SAP reversed to single pentamers when purified SAP was incorporated into SAP-depleted serum....

  11. Polyneuropathy as Novel Initial Manifestation in a Case of “Nonsecretory” POEMS Syndrome with Sjögren’s Syndrome

    Directory of Open Access Journals (Sweden)

    Minrui Liang

    2017-01-01

    Full Text Available POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes is a paraneoplastic syndrome driven by plasma cell dyscrasias. We report a patient with novel initial manifestation of polyneuropathy, which was considered due to Sjögren’s syndrome but with poor response to methylprednisolone (120 mg/d and intravenous immunoglobulin (IVIg. Further investigation by imaging tests and following biopsy eventually confirmed the diagnosis of POEMS syndrome secondary to solitary plasmocytoma. To our knowledge, this is the first reported case of POEMS syndrome with Sjögren’s syndrome occurring in the absence of a peripheral monoclonal gammopathy, highlighting the diagnostic challenges posed by this disease and reviewing the diagnostic role of (18 F-FDG PET/CT in POEMS syndrome.

  12. Amyloid Cardiomyopathy in Hereditary Transthyretin V30M Amyloidosis - Impact of Sex and Amyloid Fibril Composition.

    Directory of Open Access Journals (Sweden)

    Sandra Arvidsson

    Full Text Available Transthyretin V30M (ATTR V30M amyloidosis is a phenotypically diverse disease with symptoms ranging from predominant neuropathy to exclusive cardiac manifestations. The aims of this study were to determine the dispersion of the two types of fibrils found in Swedish ATTR V30M patients -Type A consisting of a mixture of truncated and full length ATTR fibrils and type B fibrils consisting of full length fibrils, and to estimate the severity of cardiac dysfunction in relation to fibril composition and sex.Echocardiographic data were analysed in 107 Swedish ATTR V30M patients with their fibril composition determined as either type A or type B. Measurements of left ventricular (LV dimensions and evaluation of systolic and diastolic function including speckle tracking derived strain were performed. Patients were grouped according to fibril type and sex. Multivariate linear regression was utilised to determine factors of significant impact on LV thickness.There was no significant difference in proportions of the two types of fibrils between men and women. In patients with type A fibrils, women had significantly lower median septal (p = 0.007 and posterior wall thicknesses (p = 0.010, lower median LV mass indexed to height (p = 0.008, and higher septal strain (p = 0.037, as compared to males. These differences were not apparent in patients with type B fibrils. Multiple linear regression analysis revealed that fibril type, sex and age all had significant impact on LV septal thickness.This study demonstrates a clear difference between sexes in the severity of amyloid heart disease in ATTR V30M amyloidosis patients. Even though type A fibrils were associated with more advanced amyloid heart disease compared to type B, women with type A fibrils generally developed less cardiac infiltration than men. The differences may explain the better outcome for liver transplanted late-onset female patients compared to males.

  13. The facilitative effect of transcranial direct current stimulation on visuospatial working memory in patients with diabetic polyneuropathy: a pre-post sham-controlled study

    Directory of Open Access Journals (Sweden)

    YI-JEN WU

    2016-09-01

    Full Text Available Diabetes mellitus (DM can lead to diabetic polyneuropathy (DPN and cognitive deficits that manifest as peripheral and central neuropathy, respectively. In this study we investigated the relationship between visuospatial working memory (VSWM capacity and DPN severity, and attempted to improve VSWM in DPN patients via the use of transcranial direct current stimulation (tDCS. Sixteen DPN patients and sixteen age- and education-matched healthy control subjects received Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV and Montreal Cognitive Assessment (MOCA for baseline cognitive assessment. A forward- and backward-recall computerized Corsi block tapping task (CBT, both with and without a concurrent motor interference task was used to measure VSWM capacity. Each DPN patient underwent a pre-treatment CBT, followed by tDCS or sham treatment, then a post-treatment CBT on two separate days. We found that although patients with severe DPN (Dyck’s grade 2a or 2b showed comparable general intelligence scores on WAIS-IV as their age- and education-matched healthy counterparts, they nonetheless showed mild cognitive impairment on MOCA and working memory deficit on digit-span test of WAIS-IV. Furthermore, patients’ peripheral nerve conduction velocity (NCV was positively correlated with their VSWM span in the most difficult CBT condition that involved backward-recall with motor interference such that patients with worse NCV also had lower VSWM span. Most importantly, anodal tDCS over the right DLPFC was able to improve low-performing patients’ VSWM span to be on par with the high-performers, thereby eliminating the correlation between NCV and VSWM. In summary, these findings suggest that 1 mild cognitive impairment and severe peripheral neuropathy can coexist with unequal severity in diabetic patients, 2 the positive correlation of VSWM and NCV suggests a link between peripheral and central neuropathies and 3 anodal tDCS over the right DLPFC can

  14. Different Factors Affecting Human ANP Amyloid Aggregation and Their Implications in Congestive Heart Failure

    Science.gov (United States)

    Millucci, Lia; Paccagnini, Eugenio; Ghezzi, Lorenzo; Bernardini, Giulia; Braconi, Daniela; Laschi, Marcella; Consumi, Marco; Spreafico, Adriano; Tanganelli, Piero; Lupetti, Pietro; Magnani, Agnese; Santucci, Annalisa

    2011-01-01

    Aims Atrial Natriuretic Peptide (ANP)-containing amyloid is frequently found in the elderly heart. No data exist regarding ANP aggregation process and its link to pathologies. Our aims were: i) to experimentally prove the presumptive association of Congestive Heart Failure (CHF) and Isolated Atrial Amyloidosis (IAA); ii) to characterize ANP aggregation, thereby elucidating IAA implication in the CHF pathogenesis. Methods and Results A significant prevalence (85%) of IAA was immunohistochemically proven ex vivo in biopsies from CHF patients. We investigated in vitro (using Congo Red, Thioflavin T, SDS-PAGE, transmission electron microscopy, infrared spectroscopy) ANP fibrillogenesis, starting from α-ANP as well as the ability of dimeric β-ANP to promote amyloid formation. Different conditions were adopted, including those reproducing β-ANP prevalence in CHF. Our results defined the uncommon rapidity of α-ANP self-assembly at acidic pH supporting the hypothesis that such aggregates constitute the onset of a fibrillization process subsequently proceeding at physiological pH. Interestingly, CHF-like conditions induced the production of the most stable and time-resistant ANP fibrils suggesting that CHF affected people may be prone to develop IAA. Conclusions We established a link between IAA and CHF by ex vivo examination and assessed that β-ANP is, in vitro, the seed of ANP fibrils. Our results indicate that β-ANP plays a crucial role in ANP amyloid deposition under physiopathological CHF conditions. Overall, our findings indicate that early IAA-related ANP deposition may occur in CHF and suggest that these latter patients should be monitored for the development of cardiac amyloidosis. PMID:21814559

  15. Population studies of sporadic cerebral amyloid angiopathy and dementia: a systematic review

    Directory of Open Access Journals (Sweden)

    Wharton Stephen B

    2009-01-01

    Full Text Available Abstract Background Deposition of amyloid-β (Aβ in vessel walls of the brain as cerebral amyloid angiopathy (CAA could be a major factor in the pathogenesis of dementia. Here we investigate the relationship between dementia and the prevalence of CAA in older populations. We searched the literature for prospective population-based epidemiological clinicopathological studies, free of the biases of other sampling techniques, which were used as a comparison. Methods To identify population-based studies assessing CAA and dementia, a previous systematic review of population-based clinicopathological studies of ageing and dementia was employed. To identify selected-sample studies, PsychInfo (1806–April Week 3 2008, OVID MEDLINE (1950–April Week 2 2008 and Pubmed (searched 21 April 2008 databases were searched using the term "amyloid angiopathy". These databases were also employed to search for any population-based studies not included in the previous systematic review. Studies were included if they reported the prevalence of CAA relative to a dementia classification (clinical or neuropathological. Results Four population-based studies were identified. They showed that on average 55–59% of those with dementia displayed CAA (of any severity compared to 28–38% of the non-demented. 37–43% of the demented displayed severe CAA in contrast to 7–24% of the non-demented. There was no overlap in the range of these averages and they were less variable and lower than those reported in 38 selected sample studies (demented v non-demented: 32–100 v 0–77% regardless of severity; 0–50 v 0–11% for severe only. Conclusion CAA prevalence in populations is consistently higher in the demented as compared to the non-demented. This supports a significant role for CAA in the pathogenesis of dementia.

  16. Enhancement of Herpes Simplex Virus (HSV Infection by Seminal Plasma and Semen Amyloids Implicates a New Target for the Prevention of HSV Infection

    Directory of Open Access Journals (Sweden)

    Lilith Torres

    2015-04-01

    Full Text Available Human herpesviruses cause different infectious diseases, resulting in world-wide health problems. Sexual transmission is a major route for the spread of both herpes simplex virus-1 (HSV-1 and -2. Semen plays an important role in carrying the viral particle that invades the vaginal or rectal mucosa and, thereby, initiates viral replication. Previously, we demonstrated that the amyloid fibrils semenogelin (SEM and semen-derived enhancer of viral infection (SEVI, and seminal plasma (SP augment cytomegalovirus infection (Tang et al., J. Virol 2013. Whether SEM or SEVI amyloids or SP could also enhance other herpesvirus infections has not been examined. In this study, we found that the two amyloids as well as SP strongly enhance both HSV-1 and -2 infections in cell culture. Along with SP, SEM and SEVI amyloids enhanced viral entry and increased infection rates by more than 10-fold, as assessed by flow cytometry assay and fluorescence microscopy. Viral replication was increased by about 50- to 100-fold. Moreover, viral growth curve assays showed that SEM and SEVI amyloids, as well as SP, sped up the kinetics of HSV replication such that the virus reached its replicative peak more quickly. The interactions of SEM, SEVI, and SP with HSVs are direct. Furthermore, we discovered that the enhancing effects of SP, SEM, and SEVI can be significantly reduced by heparin, a sulfated polysaccharide with an anionic charge. It is probable that heparin abrogates said enhancing effects by interfering with the interaction of the viral particle and the amyloids, which interaction results in the binding of the viral particles and both SEM and SEVI.

  17. Establishing and validating the fluorescent amyloid ligand h-FTAA (heptamer formyl thiophene acetic acid) to identify transthyretin amyloid deposits in carpal tunnel syndrome.

    Science.gov (United States)

    Hahn, Katharina; Nilsson, K Peter R; Hammarström, Per; Urban, Peter; Meliss, Rolf Rüdiger; Behrens, Hans-Michael; Krüger, Sandra; Röcken, Christoph

    2017-06-01

    Transthyretin-derived (ATTR) amyloidosis is a frequent finding in carpal tunnel syndrome. We tested the following hypotheses: the novel fluorescent amyloid ligand heptameric formic thiophene acetic acid (h-FTAA) has a superior sensitivity for the detection of amyloid compared with Congo red-staining; Amyloid load correlates with patient gender and/or patient age. We retrieved 208 resection specimens obtained from 184 patients with ATTR amyloid in the carpal tunnel. Serial sections were stained with Congo red, h-FTAA and an antibody directed against transthyretin (TTR). Stained sections were digitalized and forwarded to computational analyses. The amount of amyloid was correlated with patient demographics. Amyloid stained intensely with h-FTAA and an anti-TTR-antibody. Congo red-staining combined with fluorescence microscopy was significantly less sensitive than h-FTAA-fluorescence and TTR-immunostaining: the highest percentage area was found in TTR-immunostained sections, followed by h-FTAA and Congo red. The Pearson correlation coefficient was .8 (Congo red vs. h-FTAA) and .9 (TTR vs. h-FTAA). Amyloid load correlated with patient gender, anatomical site and patient age. h-FTAA is a highly sensitive method to detect even small amounts of ATTR amyloid in the carpal tunnel. The staining protocol is easy and h-FTAA may be a much more sensitive procedure to detect amyloid at an earlier stage.

  18. Difference in aggregation between functional and toxic amyloids studied by atomistic simulations

    Science.gov (United States)

    Carballo Pacheco, Martin; Ismail, Ahmed E.; Strodel, Birgit

    Amyloids are highly structured protein aggregates, normally associated with neurodegenerative diseases such as Alzheimer's disease. In recent years, a number of nontoxic amyloids with physiologically normal functions, called functional amyloids, have been found. It is known that soluble small oligomers are more toxic than large fibrils. Thus, we study with atomistic explicit-solvent molecular dynamics simulations the oligomer formation of the amyloid- β peptide Aβ25 - 35, associated with Alzheimer's disease, and two functional amyloid-forming tachykinin peptides: kassinin and neuromedin K. Our simulations show that monomeric peptides in extended conformations aggregate faster than those in collapsed hairpin-like conformations. In addition, we observe faster aggregation by functional amyloids than toxic amyloids, which could explain their lack of toxicity.

  19. Multiple isoforms of the human pentraxin serum amyloid P component

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH

    1995-01-01

    Human serum amyloid P component (SAP) isolated from 20 healthy individuals was analyzed by anion exchange chromatography and isoelectric focusing (IEF) in order to investigate the existence of multiple forms of SAP and interindividual structural differences. Anion exchange chromatography showed one...

  20. Amyloid-β positron emission tomography imaging probes

    DEFF Research Database (Denmark)

    Kepe, Vladimir; Moghbel, Mateen C; Långström, Bengt

    2013-01-01

    , a number of factors appear to preclude these probes from clinical utilization. As the available "amyloid specific" positron emission tomography imaging probes have failed to demonstrate diagnostic value and have shown limited utility for monitoring therapeutic interventions in humans, a debate...

  1. Aggregation properties of a short peptide that mediates amyloid fibril ...

    Indian Academy of Sciences (India)

    Short peptides have been identified from amyloidogenic proteins that form amyloid fibrils in isolation. The hexapeptide stretch 21DIDLHL26 has been shown to be important in the self-assembly of the Src homology 3 (SH3) domain of p85 subunit of bovine phosphatidylinositol-3-kinase (PI3-SH3). The SH3 domain of ...

  2. Cold denaturation of α-synuclein amyloid fibrils.

    Science.gov (United States)

    Ikenoue, Tatsuya; Lee, Young-Ho; Kardos, József; Saiki, Miyu; Yagi, Hisashi; Kawata, Yasushi; Goto, Yuji

    2014-07-21

    Although amyloid fibrils are associated with numerous pathologies, their conformational stability remains largely unclear. Herein, we probe the thermal stability of various amyloid fibrils. α-Synuclein fibrils cold-denatured to monomers at 0-20 °C and heat-denatured at 60-110 °C. Meanwhile, the fibrils of β2-microglobulin, Alzheimer's Aβ1-40/Aβ1-42 peptides, and insulin exhibited only heat denaturation, although they showed a decrease in stability at low temperature. A comparison of structural parameters with positive enthalpy and heat capacity changes which showed opposite signs to protein folding suggested that the burial of charged residues in fibril cores contributed to the cold denaturation of α-synuclein fibrils. We propose that although cold-denaturation is common to both native proteins and misfolded fibrillar states, the main-chain dominated amyloid structures may explain amyloid-specific cold denaturation arising from the unfavorable burial of charged side-chains in fibril cores. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Outcome markers for clinical trials in cerebral amyloid angiopathy

    NARCIS (Netherlands)

    S.M. Greenberg (Steven); R.A.S. Salman (Rustam Al-Shahi); G.J. Biessels (Geert Jan); M.A. van Buchem (Mark); C. Cordonnier (Charlotte); J.-M. Lee (Jin-Moo); J. Montaner (Joan); J.A. Schneider (Julie); E.E. Smith (Eric); M.W. Vernooij (Meike); D.J. Werring (David)

    2014-01-01

    textabstractEfforts are underway for early-phase trials of candidate treatments for cerebral amyloid angiopathy, an untreatable cause of haemorrhagic stroke and vascular cognitive impairment. A major barrier to these trials is the absence of consensus on measurement of treatment effectiveness. A

  4. Renal amyloid A amyloidosis as a complication of hidradenitis suppurativa

    DEFF Research Database (Denmark)

    Schandorff, Kristine D; Miller, Iben M; Krustrup, Dorrit

    2016-01-01

    Rheumatic disease is the dominant cause of amyloid A (AA) amyloidosis, but other chronic inflammatory diseases may have similar consequences. Hidradenitis suppurativa (HS) is a relatively common, but little known skin disease characterized by chronic inflammation. Here we present a case of chroni...... HS leading to biopsy-verified severe renal AA amyloidosis and dialysis dependency....

  5. Neuronal activity and amyloid plaque pathology: an update.

    Science.gov (United States)

    Ovsepian, Saak V; O'Leary, Valerie B

    2016-01-01

    A breakthrough in Alzheimer's disease (AD) research came with the discovery of the link between activity-dependent release of amyloid-β (Aβ) from neurons and formation of amyloid plaques. Along with elucidating the cellular basis of behavioral-dependent fluctuations in Aβ levels in the brain, insights have been gained toward understanding the mechanisms that warrant selective vulnerability of various forebrain circuits to amyloid pathology. The notion of elevated activity as a source of excessive Aβ production and plaque formation is, however, in conflict with ample electrophysiological data, which demonstrate exceedingly intense activity (both intrinsic and synaptic) of neurons in several brain regions that are spared or marginally affected by amyloid plaques of AD. Thus, the link between the functional load of brain circuits and their vulnerability to amyloidosis, while evident, is also complex and remains poorly understood. Here, we discuss emerging data suggestive of a major role for super-intense synchronous activity of cortical and limbic networks in excessive Aβ production and plaque formation. It is proposed that dense recurrent wiring of associative areas prone to epileptic seizures might be of critical relevance to their higher susceptibility to plaque pathology and related functional impairments.

  6. Effects of diet-induced hypercholesterolemia on amyloid ...

    Indian Academy of Sciences (India)

    2012-10-27

    Oct 27, 2012 ... A central hypothesis in the study of Alzheimer's disease (AD) is the accumulation and aggregation of β-amyloid peptide (Aβ). Recent epidemiological studies suggest that patients with elevated cholesterol and decreased estrogen levels are more susceptible to AD through Aβ accumulation. To test the ...

  7. Cooperativity among short amyloid stretches in long amyloidogenic sequences.

    Directory of Open Access Journals (Sweden)

    Lele Hu

    Full Text Available Amyloid fibrillar aggregates of polypeptides are associated with many neurodegenerative diseases. Short peptide segments in protein sequences may trigger aggregation. Identifying these stretches and examining their behavior in longer protein segments is critical for understanding these diseases and obtaining potential therapies. In this study, we combined machine learning and structure-based energy evaluation to examine and predict amyloidogenic segments. Our feature selection method discovered that windows consisting of long amino acid segments of ~30 residues, instead of the commonly used short hexapeptides, provided the highest accuracy. Weighted contributions of an amino acid at each position in a 27 residue window revealed three cooperative regions of short stretch, resemble the β-strand-turn-β-strand motif in A-βpeptide amyloid and β-solenoid structure of HET-s(218-289 prion (C. Using an in-house energy evaluation algorithm, the interaction energy between two short stretches in long segment is computed and incorporated as an additional feature. The algorithm successfully predicted and classified amyloid segments with an overall accuracy of 75%. Our study revealed that genome-wide amyloid segments are not only dependent on short high propensity stretches, but also on nearby residues.

  8. Infectious particles, stress, and induced prion amyloids: a unifying perspective.

    Science.gov (United States)

    Manuelidis, Laura

    2013-07-01

    Transmissible encephalopathies (TSEs) are believed by many to arise by spontaneous conversion of host prion protein (PrP) into an infectious amyloid (PrP-res, PrP (Sc) ) without nucleic acid. Many TSE agents reside in the environment, with infection controlled by public health measures. These include the disappearance of kuru with the cessation of ritual cannibalism, the dramatic reduction of epidemic bovine encephalopathy (BSE) by removal of contaminated feed, and the lack of endemic scrapie in geographically isolated Australian sheep with susceptible PrP genotypes. While prion protein modeling has engendered an intense focus on common types of protein misfolding and amyloid formation in diverse organisms and diseases, the biological characteristics of infectious TSE agents, and their recognition by the host as foreign entities, raises several fundamental new directions for fruitful investigation such as: (1) unrecognized microbial agents in the environmental metagenome that may cause latent neurodegenerative disease, (2) the evolutionary social and protective functions of different amyloid proteins in diverse organisms from bacteria to mammals, and (3) amyloid formation as a beneficial innate immune response to stress (infectious and non-infectious). This innate process however, once initiated, can become unstoppable in accelerated neuronal aging.

  9. Beta-amyloid, cholinergní neurony a Alzheimerova choroba

    Czech Academy of Sciences Publication Activity Database

    Kašparová, Jana; Doležal, Vladimír

    2002-01-01

    Roč. 51, č. 2 (2002), s. 82-94 ISSN 0009-0557 R&D Projects: GA MZd NF5183; GA ČR GA305/01/0283 Institutional research plan: CEZ:AV0Z5011922 Keywords : Alzheimer 's disease * beta-amyloid * cholinergic neurons Subject RIV: FR - Pharmacology ; Medidal Chemistry

  10. Raman optical activity study on insulin amyloid- and prefibril intermediate

    Czech Academy of Sciences Publication Activity Database

    Yamamoto, Shigeki; Watarai, H.

    2012-01-01

    Roč. 24, č. 2 (2012), s. 97-103 ISSN 0899-0042 Institutional research plan: CEZ:AV0Z40550506 Keywords : raman optical activity * amyloid * fibril * intermediate * insulin Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.718, year: 2012

  11. Effects of diet-induced hypercholesterolemia on amyloid ...

    Indian Academy of Sciences (India)

    A central hypothesis in the study of Alzheimer's disease (AD) is the accumulation and aggregation of -amyloid peptide (A). Recent epidemiological studies suggest that patients with elevated cholesterol and decreased estrogen levels are more susceptible to AD through A accumulation. To test the above hypothesis, we ...

  12. Multiple isoforms of the human pentraxin serum amyloid P component

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH

    1995-01-01

    Human serum amyloid P component (SAP) isolated from 20 healthy individuals was analyzed by anion exchange chromatography and isoelectric focusing (IEF) in order to investigate the existence of multiple forms of SAP and interindividual structural differences. Anion exchange chromatography showed one...... the number of bands in IEF to two indicating the existence of two types of polypeptide chains....

  13. Cerebrospinal Fluid, MRI, and Florbetaben-PET in Cerebral Amyloid Angiopathy-Related Inflammation.

    Science.gov (United States)

    Renard, Dimitri; Collombier, Laurent; Demattei, Christophe; Wacongne, Anne; Charif, Mahmoud; Ayrignac, Xavier; Azakri, Souhayla; Gaillard, Nicolas; Boudousq, Vincent; Lehmann, Sylvain; Menjot de Champfleur, Nicolas; Thouvenot, Eric

    2018-01-01

    Cerebral amyloid angiopathy-related inflammation (CAA-ri) is associated with a cerebrospinal fluid (CSF) biomarker profile similar to that observed in CAA. Few CAA-ri patients have been studied by fibrillar amyloid-β (Aβ) imaging (using 11C-Pittsburgh compound B and 18F-florbetapir, but not 18F-florbetaben). To describe CSF biomarkers, magnetic resonance imaging (MRI), and 18F-florbetaben (FBB)-positron emission tomography (PET) changes in CAA-ri patients. CSF levels of total tau, phosphorylated tau, Aβ1-42, and Aβ1-40, MRI (cerebral microbleeds count on susceptibility-weighted imaging and semi-quantitative analysis of fluid-attenuation inversion recovery white matter hyperintensities), and FBB-PET (using both cerebellar cortex and pons to calculate standardized uptake value ratios) were analyzed in nine consecutive CAA-ri patients. A median number of 769 cerebral microbleeds/patient were counted on MRI. When using the pons as reference region, amyloid load on FBB-PET was very strongly correlated to CSF Aβ1-40 levels (rho = -0.83, p = 0.008) and moderately correlated to cerebral microbleed numbers in the occipital lobes (rho = 0.59, p = 0.001), while comparisons with other CSF biomarkers were not statistically significant (total tau, rho = -0.63, p = 0.076; phosphorylated tau, rho = -0.68, p = 0.05; Aβ1-42, rho = -0.59, p = 0.09). All correlations were weaker, and not statistically significant, when using the cerebellum as reference region. A non-significant correlation (rho = -0.50, p = 0.18) was observed between CSF Aβ1-40 levels and cerebral microbleed numbers. In CAA-ri, CSF Aβ1-40 levels correlated well with amyloid load assessed by FBB-PET when the pons was used as reference, and to a lesser degree with cerebral microbleeds count on MRI. This confirms earlier data on CSF Aβ1-40 as an in vivo marker for CAA and CAA-ri.

  14. Amyloid Associated Intermittent Network Disruptions in Cognitively Intact Older Subjects: Structural Connectivity Matters

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    Susanne G. Mueller

    2017-12-01

    Full Text Available Observations in animal models suggest that amyloid can cause network hypersynchrony in the early preclinical phase of Alzheimer's disease (AD. The aim of this study was (a to obtain evidence of paroxysmal hypersynchrony in cognitively intact subjects (CN with increased brain amyloid load from task-free fMRI exams using a dynamic analysis approach, (b to investigate if and how hypersynchrony interferes with memory performance, and (c to describe its relationship with gray and white matter connectivity. Florbetapir-F18 PET and task-free 3T functional and structural MRI were acquired in 47 CN (age = 70.6 ± 6.6, 17 were amyloid pos (florbetapir SUVR >1.11. A parcellation scheme encompassing 382 regions of interest was used to extract regional gray matter volumes, FA-weighted fiber tracts and regional BOLD signals. Graph analysis was used to characterize the gray matter atrophy profile and the white matter connectivity of each subject. The fMRI data was processed using a combination of sliding windows, graph and hierarchical cluster analysis. Each activity cluster was characterized by identifying strength dispersion (difference between pos and neg strength their maximal and minimal pos and neg strength rois and by investigating their distribution and association with memory performance and gray and white matter connectivity using spearman rank correlations (FDR p < 0.05. The cluster analysis identified eight different activity clusters. Cluster 8 was characterized by the largest strength dispersion indicating hypersynchrony. Its duration/subject was positively correlated with amyloid load (r = 0.42, p = 0.03 and negatively with memory performance (CVLT delayed recall r = −0.39 p = 0.04. The assessment of the regional strength distribution indicated a functional disconnection between mesial temporal structures and the rest of the brain. White matter connectivity was increased in left lateral and mesial temporal lobe and was positively correlated

  15. Polymorphic structures of Alzheimer's β-amyloid globulomers.

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    Xiang Yu

    Full Text Available BACKGROUND: Misfolding and self-assembly of Amyloid-β (Aβ peptides into amyloid fibrils is pathologically linked to the development of Alzheimer's disease. Polymorphic Aβ structures derived from monomers to intermediate oligomers, protofilaments, and mature fibrils have been often observed in solution. Some aggregates are on-pathway species to amyloid fibrils, while the others are off-pathway species that do not evolve into amyloid fibrils. Both on-pathway and off-pathway species could be biologically relevant species. But, the lack of atomic-level structural information for these Aβ species leads to the difficulty in the understanding of their biological roles in amyloid toxicity and amyloid formation. METHODS AND FINDINGS: Here, we model a series of molecular structures of Aβ globulomers assembled by monomer and dimer building blocks using our peptide-packing program and explicit-solvent molecular dynamics (MD simulations. Structural and energetic analysis shows that although Aβ globulomers could adopt different energetically favorable but structurally heterogeneous conformations in a rugged energy landscape, they are still preferentially organized by dynamic dimeric subunits with a hydrophobic core formed by the C-terminal residues independence of initial peptide packing and organization. Such structural organizations offer high structural stability by maximizing peptide-peptide association and optimizing peptide-water solvation. Moreover, curved surface, compact size, and less populated β-structure in Aβ globulomers make them difficult to convert into other high-order Aβ aggregates and fibrils with dominant β-structure, suggesting that they are likely to be off-pathway species to amyloid fibrils. These Aβ globulomers are compatible with experimental data in overall size, subunit organization, and molecular weight from AFM images and H/D amide exchange NMR. CONCLUSIONS: Our computationally modeled Aβ globulomers provide useful

  16. Amyloid and tau cerebrospinal fluid biomarkers in HIV infection

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    Rosengren Lars

    2009-12-01

    Full Text Available Abstract Background Because of the emerging intersections of HIV infection and Alzheimer's disease, we examined cerebrospinal fluid (CSF biomarkers related of amyloid and tau metabolism in HIV-infected patients. Methods In this cross-sectional study we measured soluble amyloid precursor proteins alpha and beta (sAPPα and sAPPβ, amyloid beta fragment 1-42 (Aβ1-42, and total and hyperphosphorylated tau (t-tau and p-tau in CSF of 86 HIV-infected (HIV+ subjects, including 21 with AIDS dementia complex (ADC, 25 with central nervous system (CNS opportunistic infections and 40 without neurological symptoms and signs. We also measured these CSF biomarkers in 64 uninfected (HIV- subjects, including 21 with Alzheimer's disease, and both younger and older controls without neurological disease. Results CSF sAPPα and sAPPβ concentrations were highly correlated and reduced in patients with ADC and opportunistic infections compared to the other groups. The opportunistic infection group but not the ADC patients had lower CSF Aβ1-42 in comparison to the other HIV+ subjects. CSF t-tau levels were high in some ADC patients, but did not differ significantly from the HIV+ neuroasymptomatic group, while CSF p-tau was not increased in any of the HIV+ groups. Together, CSF amyloid and tau markers segregated the ADC patients from both HIV+ and HIV- neuroasymptomatics and from Alzheimer's disease patients, but not from those with opportunistic infections. Conclusions Parallel reductions of CSF sAPPα and sAPPβ in ADC and CNS opportunistic infections suggest an effect of CNS immune activation or inflammation on neuronal amyloid synthesis or processing. Elevation of CSF t-tau in some ADC and CNS infection patients without concomitant increase in p-tau indicates neural injury without preferential accumulation of hyperphosphorylated tau as found in Alzheimer's disease. These biomarker changes define pathogenetic pathways to brain injury in ADC that differ from those

  17. Surface Mediated Self-Assembly of Amyloid Peptides

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    Fakhraai, Zahra

    2015-03-01

    Amyloid fibrils have been considered as causative agents in many neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, type II diabetes and amyloidosis. Amyloid fibrils form when proteins or peptides misfold into one dimensional crystals of stacked beta-sheets. In solution, amyloid fibrils form through a nucleation and growth mechanism. The rate limiting nucleation step requires a critical concentration much larger than those measured in physiological conditions. As such the exact origins of the seeds or oligomers that result in the formation of fully mature fibrils in the body remain topic intense studies. It has been suggested that surfaces and interfaces can enhance the fibrillization rate. However, studies of the mechanism and kinetics of the surface-mediated fibrillization are technologically challenging due to the small size of the oligomer and protofibril species. Using smart sample preparation technique to dry the samples after various incubation times we are able to study the kinetics of fibril formation both in solution and in the vicinity of various surfaces using high-resolution atomic force microscopy. These studies elucidate the role of surfaces in catalyzing amyloid peptide formation through a nucleation-free process. The nucleation free self-assembly is rapid and requires much smaller concentrations of peptides or proteins. We show that this process resembles diffusion limited aggregation and is governed by the peptide adhesion rate, two -dimensional diffusion of the peptides on the surface, and preferential interactions between the peptides. These studies suggest an alternative pathway for amyloid formation may exist, which could lead to new criteria for disease prevention and alternative therapies. Research was partially supported by a seed grant from the National Institute of Aging of the National Institutes of Health (NIH) under Award Number P30AG010124 (PI: John Trojanowski) and the University of Pennsylvania.

  18. A Survey of FDG- and Amyloid-PET Imaging in Dementia and GRADE Analysis

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    Perani Daniela

    2014-01-01

    Full Text Available PET based tools can improve the early diagnosis of Alzheimer’s disease (AD and differential diagnosis of dementia. The importance of identifying individuals at risk of developing dementia among people with subjective cognitive complaints or mild cognitive impairment has clinical, social, and therapeutic implications. Within the two major classes of AD biomarkers currently identified, that is, markers of pathology and neurodegeneration, amyloid- and FDG-PET imaging represent decisive tools for their measurement. As a consequence, the PET tools have been recognized to be of crucial value in the recent guidelines for the early diagnosis of AD and other dementia conditions. The references based recommendations, however, include large PET imaging literature based on visual methods that greatly reduces sensitivity and specificity and lacks a clear cut-off between normal and pathological findings. PET imaging can be assessed using parametric or voxel-wise analyses by comparing the subject’s scan with a normative data set, significantly increasing the diagnostic accuracy. This paper is a survey of the relevant literature on FDG and amyloid-PET imaging aimed at providing the value of quantification for the early and differential diagnosis of AD. This allowed a meta-analysis and GRADE analysis revealing high values for PET imaging that might be useful in considering recommendations.

  19. Detection of AA76, a Common Form of Amyloid A Protein, as a Way of Diagnosing AA Amyloidosis.

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    Sato, Junji; Okuda, Yasuaki; Kuroda, Takeshi; Yamada, Toshiyuki

    2016-01-01

    Reactive amyloid deposits consist of amyloid A (AA) proteins, the degradation products of serum amyloid A (SAA). Since the most common species of AA is the amino terminal portion produced by cleavage between residues 76 and 77 of SAA (AA76), the presence of AA76 in tissues could be a consequence of AA amyloid deposition. This study assessed the diagnostic significance of the detection of AA76 for AA amyloidosis using two different approaches. Biopsy specimens (n=130 from 54 subjects) from gastroduodenal mucosa or abdominal fat (n=9 from 9 subjects) of patients who had already been diagnosed with or were suspected of having AA amyloidosis were used. Fixed mucosal sections were subjected to immunohistochemistry using a newly developed antibody recognizing the carboxyl terminal end of AA76 (anti-AA76). The non-fixed materials from gastroduodenal mucosa or abdominal fat were subjected to immunoblotting for detection of the size of AA76. Among the gastroduodenal specimens (n=115) from already diagnosed patients, the positive rates of Congo red staining, immunohistochemistry using anti-AA76, and immunoblotting were 68.4%, 73.0%, and 92.2%, respectively. The anti-AA76 did not stain the supposed SAA in the blood or leakage, which was stained by anti-SAA antibody. AA76 was not detected either by immunohistochemistry or by immunoblot in the materials from patients in whom AA amyloidosis had been ruled out. In the abdominal fat, the immunoblot detected AA76 in 8 materials from 8 already diagnosed patients and did not in 1 patient whose gastroduodenal mucosa was negative. In conclusion, the detection of AA76 may alter the ability to diagnose AA amyloidosis. In immunohistochemistry for fixed specimens, the new anti-AA76 antibody can improve the specificity. Immunoblot for non-fixed materials, which can considerably improve the sensitivity, should be beneficial for small materials like abdominal fat. © 2016 by the Association of Clinical Scientists, Inc.

  20. The molecular mass of dextran used to modify magnetite nanoparticles affects insulin amyloid aggregation

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    Siposova, Katarina [Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Kosice (Slovakia); Pospiskova, Kristyna [Regional Centre of Advanced Technologies and Materials, Palacky University, Olomouc (Czech Republic); Bednarikova, Zuzana [Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Kosice (Slovakia); Department of Biochemistry, Faculty of Science, Safarik University, Kosice (Slovakia); Safarik, Ivo [Regional Centre of Advanced Technologies and Materials, Palacky University, Olomouc (Czech Republic); Department of Nanobiotechnology, Biology Centre, ISB, CAS, Ceske Budejovice (Czech Republic); Safarikova, Mirka [Department of Nanobiotechnology, Biology Centre, ISB, CAS, Ceske Budejovice (Czech Republic); Kubovcikova, Martina; Kopcansky, Peter [Department of Magnetism, Institute of Experimental Physics, Slovak Academy of Sciences, Kosice (Slovakia); Gazova, Zuzana, E-mail: gazova@saske.sk [Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Kosice (Slovakia)

    2017-04-01

    Protein transformation from its soluble state into amyloid aggregates is associated with amyloid-related diseases. Amyloid deposits of insulin fibrils have been found in the sites of subcutaneous insulin application in patients with prolonged diabetes. Using atomic force microscopy and ThT fluorescence assay we have investigated the interference of insulin amyloid aggregation with superparamagnetic Fe{sub 3}O{sub 4}-based nanoparticles (SPIONs) coated with dextran (DEX); molecular mass of dextran was equal to 15–20, 40 or 70 kDa. The obtained data indicate that all three types of dextran coated nanoparticles (NP-FeDEXs) are able to inhibit insulin fibrillization and to destroy amyloid fibrils. The extent of anti-amyloid activities depends on the properties of NP-FeDEXs, mainly on the size of nanoparticles which is determined by molecular mass of dextran molecules. The most effective inhibiting activity was observed for the smallest nanoparticles coated with 15–20 kDa dextran. Contrary, the highest destroying activity was observed for the largest NP-FeDEX (70 kDa dextran). - Highlights: • Interference of dextran- magnetite nanoparticles with insulin amyloid aggregation. • Nanoparticles inhibited insulin fibrillization and depolymerized insulin amyloid fibrils. • Size of nanoparticles significantly influences their anti-amyloid activities. • The most effective inhibition of insulin amyloid fibrillization was detected for the smallest nanoparticles. • Contrary, DC{sub 50} values decreased with increasing size of nanoparticles.

  1. Protective properties of lysozyme on β-amyloid pathology: implications for Alzheimer disease.

    Science.gov (United States)

    Helmfors, Linda; Boman, Andrea; Civitelli, Livia; Nath, Sangeeta; Sandin, Linnea; Janefjord, Camilla; McCann, Heather; Zetterberg, Henrik; Blennow, Kaj; Halliday, Glenda; Brorsson, Ann-Christin; Kågedal, Katarina

    2015-11-01

    The hallmarks of Alzheimer disease are amyloid-β plaques and neurofibrillary tangles accompanied by signs of neuroinflammation. Lysozyme is a major player in the innate immune system and has recently been shown to prevent the aggregation of amyloid-β1-40 in vitro. In this study we found that patients with Alzheimer disease have increased lysozyme levels in the cerebrospinal fluid and lysozyme co-localized with amyloid-β in plaques. In Drosophila neuronal co-expression of lysozyme and amyloid-β1-42 reduced the formation of soluble and insoluble amyloid-β species, prolonged survival and improved the activity of amyloid-β1-42 transgenic flies. This suggests that lysozyme levels rise in Alzheimer disease as a compensatory response to amyloid-β increases and aggregation. In support of this, in vitro aggregation assays revealed that lysozyme associates with amyloid-β1-42 and alters its aggregation pathway to counteract the formation of toxic amyloid-β species. Overall, these studies establish a protective role for lysozyme against amyloid-β associated toxicities and identify increased lysozyme in patients with Alzheimer disease. Therefore, lysozyme has potential as a new biomarker as well as a therapeutic target for Alzheimer disease. Copyright © 2015. Published by Elsevier Inc.

  2. Amyloid structure exhibits polymorphism on multiple length scales in human brain tissue

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    Liu, Jiliang; Costantino, Isabel; Venugopalan, Nagarajan; Fischetti, Robert F.; Hyman, Bradley; Frosch, Matthew; Gomez-Isla, Teresa; Makowski, Lee

    2016-09-15

    Although aggregation of Aβ amyloid fibrils into plaques in the brain is a hallmark of Alzheimer's Disease (AD), the correlation between amyloid burden and severity of symptoms is weak. One possible reason is that amyloid fibrils are structurally polymorphic and different polymorphs may contribute differentially to disease. However, the occurrence and distribution of amyloid polymorphisms in human brain is poorly documented. Here we seek to fill this knowledge gap by using X-ray microdiffraction of histological sections of human tissue to map the abundance, orientation and structural heterogeneities of amyloid within individual plaques; among proximal plaques and in subjects with distinct clinical histories. A 5 µ x-ray beam was used to generate diffraction data with each pattern arising from a scattering volume of only ~ 450 µ3 , making possible collection of dozens to hundreds of diffraction patterns from a single amyloid plaque. X-ray scattering from these samples exhibited all the properties expected for scattering from amyloid. Amyloid distribution was mapped using the intensity of its signature 4.7 Å reflection which also provided information on the orientation of amyloid fibrils across plaques. Margins of plaques exhibited a greater degree of orientation than cores and orientation around blood vessels frequently appeared tangential. Variation in the structure of Aβ fibrils is reflected in the shape of the 4.7 Å peak which usually appears as a doublet. Variations in this peak correspond to differences between the structure of amyloid within cores of plaques and at their periphery. Examination of tissue from a mismatch case - an individual with high plaque burden but no overt signs of dementia at time of death - revealed a diversity of structure and spatial distribution of amyloid that is distinct from typical AD cases. We demonstrate the existence of structural polymorphisms among amyloid within and among plaques of a single individual and suggest

  3. Interaction of the molecular chaperone DNAJB6 with growing amyloid-beta 42 (Aβ42) aggregates leads to sub-stoichiometric inhibition of amyloid formation

    NARCIS (Netherlands)

    Månsson, Cecilia; Arosio, Paolo; Hussein, Rasha; Kampinga, Harm H; Hashem, Reem M; Boelens, Wilbert C; Dobson, Christopher M; Knowles, Tuomas P J; Linse, Sara; Emanuelsson, Cecilia

    2014-01-01

    The human molecular chaperone protein DNAJB6 was recently found to inhibit the formation of amyloid fibrils from polyglutamine peptides associated with neurodegenerative disorders such as Huntington's disease. We show in the present study that DNAJB6 also inhibits amyloid formation by an even more

  4. Mesenchymal Stem Cell-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Ameliorate Diabetic Polyneuropathy in Mice

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    Tatsuhito Himeno

    2013-01-01

    Full Text Available Background. Although pathological involvements of diabetic polyneuropathy (DPN have been reported, no dependable treatment of DPN has been achieved. Recent studies have shown that mesenchymal stem cells (MSCs ameliorate DPN. Here we demonstrate a differentiation of induced pluripotent stem cells (iPSCs into MSC-like cells and investigate the therapeutic potential of the MSC-like cell transplantation on DPN. Research Design and Methods. For induction into MSC-like cells, GFP-expressing iPSCs were cultured with retinoic acid, followed by adherent culture for 4 months. The MSC-like cells, characterized with flow cytometry and RT-PCR analyses, were transplanted into muscles of streptozotocin-diabetic mice. Three weeks after the transplantation, neurophysiological functions were evaluated. Results. The MSC-like cells expressed MSC markers and angiogenic/neurotrophic factors. The transplanted cells resided in hindlimb muscles and peripheral nerves, and some transplanted cells expressed S100β in the nerves. Impairments of current perception thresholds, nerve conduction velocities, and plantar skin blood flow in the diabetic mice were ameliorated in limbs with the transplanted cells. The capillary number-to-muscle fiber ratios were increased in transplanted hindlimbs of diabetic mice. Conclusions. These results suggest that MSC-like cell transplantation might have therapeutic effects on DPN through secreting angiogenic/neurotrophic factors and differentiation to Schwann cell-like cells.

  5. Mesenchymal stem cell-like cells derived from mouse induced pluripotent stem cells ameliorate diabetic polyneuropathy in mice.

    Science.gov (United States)

    Himeno, Tatsuhito; Kamiya, Hideki; Naruse, Keiko; Cheng, Zhao; Ito, Sachiko; Kondo, Masaki; Okawa, Tetsuji; Fujiya, Atsushi; Kato, Jiro; Suzuki, Hirohiko; Kito, Tetsutaro; Hamada, Yoji; Oiso, Yutaka; Isobe, Kenichi; Nakamura, Jiro

    2013-01-01

    Although pathological involvements of diabetic polyneuropathy (DPN) have been reported, no dependable treatment of DPN has been achieved. Recent studies have shown that mesenchymal stem cells (MSCs) ameliorate DPN. Here we demonstrate a differentiation of induced pluripotent stem cells (iPSCs) into MSC-like cells and investigate the therapeutic potential of the MSC-like cell transplantation on DPN. For induction into MSC-like cells, GFP-expressing iPSCs were cultured with retinoic acid, followed by adherent culture for 4 months. The MSC-like cells, characterized with flow cytometry and RT-PCR analyses, were transplanted into muscles of streptozotocin-diabetic mice. Three weeks after the transplantation, neurophysiological functions were evaluated. The MSC-like cells expressed MSC markers and angiogenic/neurotrophic factors. The transplanted cells resided in hindlimb muscles and peripheral nerves, and some transplanted cells expressed S100 β in the nerves. Impairments of current perception thresholds, nerve conduction velocities, and plantar skin blood flow in the diabetic mice were ameliorated in limbs with the transplanted cells. The capillary number-to-muscle fiber ratios were increased in transplanted hindlimbs of diabetic mice. These results suggest that MSC-like cell transplantation might have therapeutic effects on DPN through secreting angiogenic/neurotrophic factors and differentiation to Schwann cell-like cells.

  6. Polyneuropathy, anti-tuberculosis treatment and the role of pyridoxine in the HIV/AIDS era: a systematic review.

    Science.gov (United States)

    van der Watt, J J; Harrison, T B; Benatar, M; Heckmann, J M

    2011-06-01

    Tuberculosis (TB) is increasing in incidence in certain parts of the world, particularly where there is a co-epidemic of human immunodeficiency virus/acquired immune-deficiency syndrome (HIV/AIDS), and it is associated with a significant degree of morbidity and mortality. One of the most common complications of anti-tuberculosis treatment is the development of a painful isoniazid (INH) associated polyneuropathy (PN), which is preventable with adequate pyridoxine supplementation. As PN is also the most frequent neurological complication associated with HIV infection, subjects who are HIV and TB co-infected may be at increased risk of developing PN. In this review, we explore current knowledge of anti-tuberculosis drug associated PN focusing on INH and its relationship to pyridoxine, as well as the additional impact of antiretroviral treatment and TB-HIV co-infection. It is evident that guidelines established for the prevention and treatment of this problem differ between industrialised and developing countries, and that further research is needed to define the optimum dosing of pyridoxine supplementation in populations where there is a significant burden of TB and HIV.

  7. Incidence and Natural History of Idiopathic Chronic Inflammatory Demyelinating Polyneuropathy: A Population-Based Study in Iceland.

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    Hafsteinsdottir, Brynhildur; Olafsson, Elias

    2016-01-01

    We report a population-based study conducted in Iceland to determine the incidence, clinical characteristics and prognosis of idiopathic chronic inflammatory demyelinating polyneuropathy (CIDP) during a 21-year period. Cases were identified from the records of all practicing neurologists in the country, the only neurology department in the country and both neurophysiology laboratories. All index cases met the 2010 European Federation of Neurological Societies/Peripheral Nerve Society criteria for CIDP. Nineteen individuals fulfilled the diagnostic criteria during the study period. The average annual incidence was 0.3/100,000 (95% CI 0.04-2.47). There were 14 men (74%) in a gender ratio of 1:2.8. The mean age at diagnosis was 57 (range 19-81 years): women, 36 years and men, 63 years; p = 0.0006. The disease course was remitting-relapsing in 21% and chronic progressive or monophasic in 79%. The average length of follow-up was 6.9 years. The standardized mortality ratio for the 21-year study period was 0.9 (95% CI 0.3-2.2). We believe we have identified all diagnosed with CIDP in Iceland during a 21-year period. Many had no or only limited disease progression over the years and mortality is not increased compared with the general population. © 2016 S. Karger AG, Basel.

  8. Weakness in the ICU: Guillain-Barré syndrome, myasthenia gravis, and critical illness polyneuropathy/myopathy.

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    Green, Deborah M

    2005-11-01

    Weakness in the ICU may be caused by a number of disorders. Guillain-Barré syndrome (GBS) and myasthenia gravis (MG) are examples of conditions that might lead to an ICU admission. The most likely cause of weakness after ICU admission is critical illness polyneuropathy/myopathy (CIP/M). Studies have attempted to determine both clinical and pulmonary function criteria for the proper timing of intubation in severe GBS and MG. Optimizing medical management of patients with GBS, MG, and CIP/M is essential in reducing the high morbidity and mortality associated with these conditions. This includes measures to prevent deep venous thrombosis, gastric and decubitus ulcer prophylaxis, and chest physiotherapy. Both intravenous immunoglobulin (IVIG) and therapeutic plasma exchange (TPE) are probably equal in efficacy for the treatment of GBS, although relapse rates may differ. Treatment of MG crisis with TPE or IVIG must be followed by long-term immunosuppression. Studies suggest possible preventative measures for CIP/M such as tighter glycemic control but there are still no definitive treatments. Research to advance our knowledge of the pathogenesis of GBS, MG, and CIP/M is clearly needed to develop more specific and more effective treatments in the future. In the meantime, measures that optimize medical management can be instituted to improve outcomes in patients with these conditions, preferably in a specialized neuroscience ICU setting.

  9. Charcot-Marie-Tooth disease type 2 caused by homozygous MME gene mutation superimposed by chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Fujisawa, Miwako; Sano, Yasuteru; Omoto, Masatoshi; Ogasawara, Jyun-Ichi; Koga, Michiaki; Takashima, Hiroshi; Kanda, Takashi

    2017-09-30

    We report a 59-year-old Japanese male who developed gradually worsening weakness and numbness of distal four extremities since age 50. His parents were first cousins, and blood and cerebral spinal examinations were unremarkable. Homozygous mutation of MME gene was detected and thus he was diagnosed as autosomal-recessive Charcot-Marie-Tooth disease 2T (AR-CMT2T); however, electrophysiological examinations revealed scattered demyelinative changes including elongated terminal latency in several peripheral nerve trunks. Sural nerve biopsy showed endoneurial edema and a lot of thinly myelinated nerve fibers with uneven distribution of remnant myelinated fibers within and between fascicles. Immunoglobulin treatment was initiated considering the possibility of superimposed inflammation and demyelination, and immediate clinical as well as electrophysiological improvements were noted. Our findings indicate that AR-CMT2T caused by MME mutation predisposes to a superimposed inflammatory demyelinating neuropathy. This is the first report which documented the co-existence of CMT2 and chronic inflammatory demyelinating polyneuropathy (CIDP); however, in the peripheral nervous system, neprilysin, a product of MME gene, is more abundant in myelin sheath than in axonal component. The fragility of myelin sheath due to mutated neprilysin may trigger the detrimental immune response against peripheral myelin in this patient.

  10. Preventing effect of L-type calcium channel blockade on electrophysiological alterations in dentate gyrus granule cells induced by entorhinal amyloid pathology.

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    Hamid Gholami Pourbadie

    Full Text Available The entorhinal cortex (EC is one of the earliest affected brain regions in Alzheimer's disease (AD. EC-amyloid pathology induces synaptic failure in the dentate gyrus (DG with resultant behavioral impairment, but there is little known about its impact on neuronal properties in the DG. It is believed that calcium dyshomeostasis plays a pivotal role in the etiology of AD. Here, the effect of the EC amyloid pathogenesis on cellular properties of DG granule cells and also possible neuroprotective role of L-type calcium channel blockers (CCBs, nimodipine and isradipine, were investigated. The amyloid beta (Aβ 1-42 was injected bilaterally into the EC of male rats and one week later, electrophysiological properties of DG granule cells were assessed. Voltage clamp recording revealed appearance of giant sIPSC in combination with a decrease in sEPSC frequency which was partially reversed by CCBs in granule cells from Aβ treated rats. EC amyloid pathogenesis induced a significant reduction of input resistance (Rin accompanied by a profound decreased excitability in the DG granule cells. However, daily administration of CCBs, isradipine or nimodipine (i.c.v. for 6 days, almost preserved the normal excitability against Aβ. In conclusion, lower tendency to fire AP along with reduced Rin suggest that DG granule cells might undergo an alteration in the membrane ion channel activities which finally lead to the behavioral deficits observed in animal models and patients with early-stage Alzheimer's disease.

  11. Nonsteroidal Selective Androgen Receptor Modulators and Selective Estrogen Receptor β Agonists Moderate Cognitive Deficits and Amyloid-β Levels in a Mouse Model of Alzheimer’s Disease

    Science.gov (United States)

    2013-01-01

    Decreases of the sex steroids, testosterone and estrogen, are associated with increased risk of Alzheimer’s disease. Testosterone and estrogen supplementation improves cognitive deficits in animal models of Alzheimer’s disease. Sex hormones play a role in the regulation of amyloid-β via induction of the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme. To mimic the effect of dihydrotestosterone (DHT), we administered a selective androgen receptor agonist, ACP-105, alone and in combination with the selective estrogen receptor β (ERβ) agonist AC-186 to male gonadectomized triple transgenic mice. We assessed long-term spatial memory in the Morris water maze, spontaneous locomotion, and anxiety-like behavior in the open field and in the elevated plus maze. We found that ACP-105 given alone decreases anxiety-like behavior. Furthermore, when ACP-105 is administered in combination with AC-186, they increase the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme and decrease amyloid-β levels in the brain as well as improve cognition. Interestingly, the androgen receptor level in the brain was increased by chronic treatment with the same combination treatment, ACP-105 and AC-186, not seen with DHT or ACP-105 alone. Based on these results, the beneficial effect of the selective ERβ agonist as a potential therapeutic for Alzheimer’s disease warrants further investigation. PMID:24020966

  12. Regional correlations between [11C]PIB PET and post-mortem burden of amyloid-beta pathology in a diverse neuropathological cohort

    Directory of Open Access Journals (Sweden)

    Sang Won Seo

    2017-01-01

    Full Text Available Imaging-pathological correlation studies show that in vivo amyloid-β (Aβ positron emission tomography (PET strongly predicts the presence of significant Aβ pathology at autopsy. We sought to determine whether regional PiB-PET uptake would improve sensitivity for amyloid detection in comparison with global measures (experiment 1, and to estimate the relative contributions of different Aβ aggregates to in vivo PET signal (experiment 2. In experiment 1, 54 subjects with [11C] PiB-PET during life and postmortem neuropathologic examination (85.2% with dementia, interval from PET to autopsy 3.1 ± 1.9 years were included. We assessed Thal amyloid phase (N = 36 and CERAD score (N = 54 versus both global and regional PiB SUVRs. In experiment 2 (N = 42, PiB SUVR and post-mortem amyloid β burden was analyzed in five customized regions of interest matching regions sampled at autopsy. We assessed the relative contribution of neuritic plaques (NPs, diffuse plaques (DPs and cerebral amyloid angiopathy (CAA to regional PIB SUVR using multi-linear regression. In experiment 1, there were no differences in Area Under the Curve for amyloid phase ≥ A2 and CERAD score ≥ C2 between global and highest regional PiB SUVR (p = 0.186 and 0.230. In experiment 2, when NPs, DPs, and/or CAA were included in the same model, moderate to severe NPs were independently correlated with PiB SUVR in all regions except for the inferior temporal and calcarine ROI (β = 0.414–0.804, p < 0.05, whereas DPs were independently correlated with PiB SUVR in the angular gyrus ROI (β = 0.446, p = 0.010. CAA was also associated with PiB SUVR in the inferior temporal and calcarine ROI (β = 0.222–0.355, p < 0.05. In conclusion, global PiB-PET SUVR performed as well as regional values for amyloid detection in our cohort. The substrate-specific binding of PiB might differ among the brain specific regions.

  13. Regional correlations between [11C]PIB PET and post-mortem burden of amyloid-beta pathology in a diverse neuropathological cohort.

    Science.gov (United States)

    Seo, Sang Won; Ayakta, Nagehan; Grinberg, Lea T; Villeneuve, Sylvia; Lehmann, Manja; Reed, Bruce; DeCarli, Charles; Miller, Bruce L; Rosen, Howard J; Boxer, Adam L; O'Neil, James P; Jin, Lee-Way; Seeley, William W; Jagust, William J; Rabinovici, Gil D

    2017-01-01

    Imaging-pathological correlation studies show that in vivo amyloid-β (Aβ) positron emission tomography (PET) strongly predicts the presence of significant Aβ pathology at autopsy. We sought to determine whether regional PiB-PET uptake would improve sensitivity for amyloid detection in comparison with global measures (experiment 1), and to estimate the relative contributions of different Aβ aggregates to in vivo PET signal (experiment 2). In experiment 1, 54 subjects with [ 11 C] PiB-PET during life and postmortem neuropathologic examination (85.2% with dementia, interval from PET to autopsy 3.1 ± 1.9 years) were included. We assessed Thal amyloid phase (N = 36) and CERAD score (N = 54) versus both global and regional PiB SUVRs. In experiment 2 (N = 42), PiB SUVR and post-mortem amyloid β burden was analyzed in five customized regions of interest matching regions sampled at autopsy. We assessed the relative contribution of neuritic plaques (NPs), diffuse plaques (DPs) and cerebral amyloid angiopathy (CAA) to regional PIB SUVR using multi-linear regression. In experiment 1, there were no differences in Area Under the Curve for amyloid phase ≥ A2 and CERAD score ≥ C2 between global and highest regional PiB SUVR ( p  = 0.186 and 0.230). In experiment 2, when NPs, DPs, and/or CAA were included in the same model, moderate to severe NPs were independently correlated with PiB SUVR in all regions except for the inferior temporal and calcarine ROI (β = 0.414-0.804, p  PiB SUVR in the angular gyrus ROI (β = 0.446, p  = 0.010). CAA was also associated with PiB SUVR in the inferior temporal and calcarine ROI (β = 0.222-0.355, p  PiB-PET SUVR performed as well as regional values for amyloid detection in our cohort. The substrate-specific binding of PiB might differ among the brain specific regions.

  14. Neurotrophic and Neurotoxic Effects of Amyloid |beta Protein: Reversal by Tachykinin Neuropeptides

    Science.gov (United States)

    Yankner, Bruce A.; Duffy, Lawrence K.; Kirschner, Daniel A.

    1990-10-01

    The amyloid β protein is deposited in the brains of patients with Alzheimer's disease but its pathogenic role is unknown. In culture, the amyloid β protein was neurotrophic to undifferentiated hippocampal neurons at low concentrations and neurotoxic to mature neurons at higher concentrations. In differentiated neurons, amyloid β protein caused dendritic and axonal retraction followed by neuronal death. A portion of the amyloid β protein (amino acids 25 to 35) mediated both the trophic and toxic effects and was homologous to the tachykinin neuropeptide family. The effects of the amyloid β protein were mimicked by tachykinin antagonists and completely reversed by specific tachykinin agonists. Thus, the amyloid β protein could function as a neurotrophic factor for differentiating neurons, but at high concentrations in mature neurons, as in Alzheimer's disease, could cause neuronal degeneration.

  15. Associations Between β-Amyloid Kinetics and the β-Amyloid Diurnal Pattern in the Central Nervous System.

    Science.gov (United States)

    Lucey, Brendan P; Mawuenyega, Kwasi G; Patterson, Bruce W; Elbert, Donald L; Ovod, Vitaliy; Kasten, Tom; Morris, John C; Bateman, Randall J

    2017-02-01

    Recent studies found that the concentration of amyloid-β (Aβ) fluctuates with the sleep-wake cycle. Although the amplitude of this day/night pattern attenuates with age and amyloid deposition, to our knowledge, the association of Aβ kinetics (ie, production, turnover, and clearance) with this oscillation has not been studied. To determine the association between Aβ kinetics, age, amyloid levels, and the Aβ day/night pattern in humans. We measured Aβ concentrations and kinetics in 77 adults aged 60 to 87 years with and without amyloid deposition by a novel precise mass spectrometry method at the Washington University School of Medicine in St Louis, Missouri. We compared findings of 2 orthogonal methods, enzyme-linked immunosorbent assay and mass spectrometry, to validate the day/night patterns and determine more precise estimates of the cosinor parameters. In vivo labeling of central nervous system proteins with stable isotopically labeled leucine was performed, and kinetics of Aβ40 and Aβ42 were measured. Serial cerebrospinal fluid collection via indwelling lumbar catheter over 36 to 48 hours before, during, and after in vivo labeling, with a 9-hour primed constant infusion of 13C6-leucine. The amplitude, linear increase, and other cosinor measures of each participant's serial cerebrospinal fluid Aβ concentrations and Aβ turnover rates. Of the 77 participants studied, 46 (59.7%) were men, and the mean (range) age was 72.6 (60.4-87.7) years. Day/night patterns in Aβ concentrations were more sharply defined by the precise mass spectrometry method than by enzyme-linked immunosorbent assay (mean difference of SD of residuals: Aβ40, -7.42 pM; P effects of age and amyloid on Aβ42 amplitude at least partially affect each other. Production and turnover rates suggest that day/night Aβ patterns are modulated by both production and clearance mechanisms active in sleep-wake cycles and that amyloid deposition may impair normal circadian patterns. These findings

  16. New Cyclolignans from Origanumglandulosum Active Against b -amyloid Aggregation

    Directory of Open Access Journals (Sweden)

    Abdelkader Basli

    2014-05-01

    Full Text Available Origanum glandulosum Desf is an endemic flavoring herb widely distributed in North Africa that is commonly used in traditional medicine. This oregano species is rich in essential oils but little is known about its phenolic composition. In the present study, a crude extract of O. glandulosum was prepared in order to isolate and investigate its neuroprotective potential to inhibit β-amyloid peptide (Aβ aggregation. The three major compounds of the extract were isolated: rosmarinic acid and two cyclolignans in Origanum genus, globoidnan A and a new derivative named globoidnan B. Rosmarinic acid and globoidnan A showed significant anti-aggregative activity against β amyloid aggregation (IC50 7.0 and 12.0 µM, respectively. In contrast, globoidnan B was found to be less active.

  17. Gold Nanoparticles and Microwave Irradiation Inhibit Beta-Amyloid Amyloidogenesis

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    Bastus Neus

    2008-01-01

    Full Text Available Abstract Peptide-Gold nanoparticles selectively attached to β-amyloid protein (Aβ amyloidogenic aggregates were irradiated with microwave. This treatment produces dramatic effects on the Aβ aggregates, inhibiting both the amyloidogenesis and the restoration of the amyloidogenic potential. This novel approach offers a new strategy to inhibit, locally and remotely, the amyloidogenic process, which could have application in Alzheimer’s disease therapy. We have studied the irradiation effect on the amyloidogenic process in the presence of conjugates peptide-nanoparticle by transmission electronic microscopy observations and by Thioflavine T assays to quantify the amount of fibrils in suspension. The amyloidogenic aggregates rather than the amyloid fibrils seem to be better targets for the treatment of the disease. Our results could contribute to the development of a new therapeutic strategy to inhibit the amyloidogenic process in Alzheimer’s disease.

  18. Cerebral Amyloid Angiopathy: A Case Report and Literature ...

    Directory of Open Access Journals (Sweden)

    Orkide Kutlu

    2015-03-01

    Full Text Available Cerebral amyloid angiopathy (CAA is a condition characterized by accumulation of amyloid-beta peptide in the walls of the small and medium-sized arteries of the brain and leptomeninges. This condition disrupts the structure of the vessel wall and makes it prone to bleeding. This is an important cause of intracerebral hemorrhage in elderly accompanying to Alzheimer’s disease or to a familial syndrome. Clinically, it usually presents with spontaneous lobar hemorrhage, as well as transient neurological signs, seizures, cognitive disorders, headache, incidental findings like microhaemorrhages and hemosiderosis observed on magnetic resonance (MR imaging. Herein, we report a hypertensive patient diagnosed with CAA who presented with the complaints of balance disorder while walking. CAA should be suspected in patients with lobar hemorrhage aged 65 years and over. Surgical treatment should not be performed because it could worsen the condition. Clinical improvement can be expected from supportive management, monitoring hypertension, and steroid - immunosuppressive therapies.

  19. Evolutionary perspectives on amyloid and inflammatory features of Alzheimer disease.

    Science.gov (United States)

    Finch, C E; Marchalonis, J J

    1996-01-01

    We propose that the amyloid deposits in senile plaques of Alzheimer's Disease (AD) result from ancient mechanisms in wound-healing and inflammatory processes that preceded the evolution of the inducible combinatorial immune responses characteristic of jawed vertebrates. AD plaques are unlike active plaques in MS, because antibodies, T-cells and, B cells are not conspicuous components of senile plaques or other loci of degeneration. However, senile plaques contain amyloids and other inflammatory proteins of ancient origin that appear to be made by local brain cells, including neurons, astrocytes, and microglia. We describe a highly conserved 16-mer found in pentrakins from mammals and from the horseshoe crab. The senile plaque thus provides a novel opportunity to study primitive features of complement-mediated inflammatory responses in the absence of immunoglobulins.

  20. Screening for Amyloid Aggregation by Semi-Denaturing Detergent-Agarose Gel Electrophoresis

    OpenAIRE

    Halfmann, Randal; Lindquist, Susan

    2008-01-01

    Amyloid aggregation is associated with numerous protein misfolding pathologies and underlies the infectious properties of prions, which are conformationally self-templating proteins that are thought to have beneficial roles in lower organisms. Amyloids have been notoriously difficult to study due to their insolubility and structural heterogeneity. However, resolution of amyloid polymers based on size and detergent insolubility has been made possible by Semi-Denaturing Detergent-Agarose Gel El...

  1. Primary amyloid heart disease presenting as hypertrophic obstructive cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Weston, L.T.; Raybuck, B.D.; Robinowitz, M.; Brinker, J.A.; Oetgen, W.J.

    1986-01-01

    This report describes the unusual presentation of a patient with primary cardiac amyloidosis. Initial clinical symptoms and hemodynamic studies, including Technetium-99m-pyrophosphate scintigraphy, suggested hypertrophic obstructive cardiomyopathy, but endomyocardial biopsy revealed diffuse amyloid infiltration. Only two other cases of left ventricular outflow tract obstruction due to cardiac amyloidosis have been reported. The false-negative technetium-99m-pyrophosphate scintigram in this patient argues for the use of endomyocardial biopsy to aid in the diagnosis of left ventricular hypertrophy.

  2. Crowding alone cannot account for cosolute effect on amyloid aggregation.

    Directory of Open Access Journals (Sweden)

    Shahar Sukenik

    Full Text Available Amyloid fiber formation is a specific form of protein aggregation, often resulting from the misfolding of native proteins. Aimed at modeling the crowded environment of the cell, recent experiments showed a reduction in fibrillation halftimes for amyloid-forming peptides in the presence of cosolutes that are preferentially excluded from proteins and peptides. The effect of excluded cosolutes has previously been attributed to the large volume excluded by such inert cellular solutes, sometimes termed "macromolecular crowding". Here, we studied a model peptide that can fold to a stable monomeric β-hairpin conformation, but under certain solution conditions aggregates in the form of amyloid fibrils. Using Circular Dichroism spectroscopy (CD, we found that, in the presence of polyols and polyethylene glycols acting as excluded cosolutes, the monomeric β-hairpin conformation was stabilized with respect to the unfolded state. Stabilization free energy was linear with cosolute concentration, and grew with molecular volume, as would also be predicted by crowding models. After initiating the aggregation process with a pH jump, fibrillation in the presence and absence of cosolutes was followed by ThT fluorescence, transmission electron microscopy, and CD spectroscopy. Polyols (glycerol and sorbitol increased the lag time for fibril formation and elevated the amount of aggregated peptide at equilibrium, in a cosolute size and concentration dependent manner. However, fibrillation rates remained almost unaffected by a wide range of molecular weights of soluble polyethylene glycols. Our results highlight the importance of other forces beyond the excluded volume interactions responsible for crowding that may contribute to the cosolute effects acting on amyloid formation.

  3. The contrasting effect of macromolecular crowding on amyloid fibril formation.

    Directory of Open Access Journals (Sweden)

    Qian Ma

    Full Text Available Amyloid fibrils associated with neurodegenerative diseases can be considered biologically relevant failures of cellular quality control mechanisms. It is known that in vivo human Tau protein, human prion protein, and human copper, zinc superoxide dismutase (SOD1 have the tendency to form fibril deposits in a variety of tissues and they are associated with different neurodegenerative diseases, while rabbit prion protein and hen egg white lysozyme do not readily form fibrils and are unlikely to cause neurodegenerative diseases. In this study, we have investigated the contrasting effect of macromolecular crowding on fibril formation of different proteins.As revealed by assays based on thioflavin T binding and turbidity, human Tau fragments, when phosphorylated by glycogen synthase kinase-3β, do not form filaments in the absence of a crowding agent but do form fibrils in the presence of a crowding agent, and the presence of a strong crowding agent dramatically promotes amyloid fibril formation of human prion protein and its two pathogenic mutants E196K and D178N. Such an enhancing effect of macromolecular crowding on fibril formation is also observed for a pathological human SOD1 mutant A4V. On the other hand, rabbit prion protein and hen lysozyme do not form amyloid fibrils when a crowding agent at 300 g/l is used but do form fibrils in the absence of a crowding agent. Furthermore, aggregation of these two proteins is remarkably inhibited by Ficoll 70 and dextran 70 at 200 g/l.We suggest that proteins associated with neurodegenerative diseases are more likely to form amyloid fibrils under crowded conditions than in dilute solutions. By contrast, some of the proteins that are not neurodegenerative disease-associated are unlikely to misfold in crowded physiological environments. A possible explanation for the contrasting effect of macromolecular crowding on these two sets of proteins (amyloidogenic proteins and non-amyloidogenic proteins has been

  4. Amyloid fibril systems reduce, stabilize and deliver bioavailable nanosized iron

    Science.gov (United States)

    Shen, Yi; Posavec, Lidija; Bolisetty, Sreenath; Hilty, Florentine M.; Nyström, Gustav; Kohlbrecher, Joachim; Hilbe, Monika; Rossi, Antonella; Baumgartner, Jeannine; Zimmermann, Michael B.; Mezzenga, Raffaele

    2017-07-01

    Iron-deficiency anaemia (IDA) is a major global public health problem. A sustainable and cost-effective strategy to reduce IDA is iron fortification of foods, but the most bioavailable fortificants cause adverse organoleptic changes in foods. Iron nanoparticles are a promising solution in food matrices, although their tendency to oxidize and rapidly aggregate in solution severely limits their use in fortification. Amyloid fibrils are protein aggregates initially known for their association with neurodegenerative disorders, but recently described in the context of biological functions in living organisms and emerging as unique biomaterial building blocks. Here, we show an original application for these protein fibrils as efficient carriers for iron fortification. We use biodegradable amyloid fibrils from β-lactoglobulin, an inexpensive milk protein with natural reducing effects, as anti-oxidizing nanocarriers and colloidal stabilizers for iron nanoparticles. The resulting hybrid material forms a stable protein-iron colloidal dispersion that undergoes rapid dissolution and releases iron ions during acidic and enzymatic in vitro digestion. Importantly, this hybrid shows high in vivo iron bioavailability, equivalent to ferrous sulfate in haemoglobin-repletion and stable-isotope studies in rats, but with reduced organoleptic changes in foods. Feeding the rats with these hybrid materials did not result in abnormal iron accumulation in any organs, or changes in whole blood glutathione concentrations, inferring their primary safety. Therefore, these iron-amyloid fibril hybrids emerge as novel, highly effective delivery systems for iron in both solid and liquid matrices.

  5. Curcumin Binding to Beta Amyloid: A Computational Study.

    Science.gov (United States)

    Rao, Praveen P N; Mohamed, Tarek; Teckwani, Karan; Tin, Gary

    2015-10-01

    Curcumin, a chemical constituent present in the spice turmeric, is known to prevent the aggregation of amyloid peptide implicated in the pathophysiology of Alzheimer's disease. While curcumin is known to bind directly to various amyloid aggregates, no systematic investigations have been carried out to understand its ability to bind to the amyloid aggregates including oligomers and fibrils. In this study, we constructed computational models of (i) Aβ hexapeptide (16) KLVFFA(21) octamer steric-zipper β-sheet assembly and (ii) full-length Aβ fibril β-sheet assembly. Curcumin binding in these models was evaluated by molecular docking and molecular dynamics (MD) simulation studies. In both the models, curcumin was oriented in a linear extended conformation parallel to fiber axis and exhibited better stability in the Aβ hexapeptide (16) KLVFFA(21) octamer steric-zipper model (Ebinding  = -10.05 kcal/mol) compared to full-length Aβ fibril model (Ebinding  = -3.47 kcal/mol). Analysis of MD trajectories of curcumin bound to full-length Aβ fibril shows good stability with minimum Cα-atom RMSD shifts. Interestingly, curcumin binding led to marked fluctuations in the (14) HQKLVFFA(21) region that constitute the fibril spine with RMSF values ranging from 1.4 to 3.6 Å. These results show that curcumin binding to Aβ shifts the equilibrium in the aggregation pathway by promoting the formation of non-toxic aggregates. © 2015 John Wiley & Sons A/S.

  6. Calcium signaling and amyloid toxicity in Alzheimer disease.

    Science.gov (United States)

    Demuro, Angelo; Parker, Ian; Stutzmann, Grace E

    2010-04-23

    Intracellular Ca(2+) signaling is fundamental to neuronal physiology and viability. Because of its ubiquitous roles, disruptions in Ca(2+) homeostasis are implicated in diverse disease processes and have become a major focus of study in multifactorial neurodegenerative diseases such as Alzheimer disease (AD). A hallmark of AD is the excessive production of beta-amyloid (Abeta) and its massive accumulation in amyloid plaques. In this minireview, we highlight the pathogenic interactions between altered cellular Ca(2+) signaling and Abeta in its different aggregation states and how these elements coalesce to alter the course of the neurodegenerative disease. Ca(2+) and Abeta intersect at several functional levels and temporal stages of AD, thereby altering neurotransmitter receptor properties, disrupting membrane integrity, and initiating apoptotic signaling cascades. Notably, there are reciprocal interactions between Ca(2+) pathways and amyloid pathology; altered Ca(2+) signaling accelerates Abeta formation, whereas Abeta peptides, particularly in soluble oligomeric forms, induce Ca(2+) disruptions. A degenerative feed-forward cycle of toxic Abeta generation and Ca(2+) perturbations results, which in turn can spin off to accelerate more global neuropathological cascades, ultimately leading to synaptic breakdown, cell death, and devastating memory loss. Although no cause or cure is currently known, targeting Ca(2+) dyshomeostasis as an underlying and integral component of AD pathology may result in novel and effective treatments for AD.

  7. MetAmyl: a METa-predictor for AMYLoid proteins.

    Directory of Open Access Journals (Sweden)

    Mathieu Emily

    Full Text Available The aggregation of proteins or peptides in amyloid fibrils is associated with a number of clinical disorders, including Alzheimer's, Huntington's and prion diseases, medullary thyroid cancer, renal and cardiac amyloidosis. Despite extensive studies, the molecular mechanisms underlying the initiation of fibril formation remain largely unknown. Several lines of evidence revealed that short amino-acid segments (hot spots, located in amyloid precursor proteins act as seeds for fibril elongation. Therefore, hot spots are potential targets for diagnostic/therapeutic applications, and a current challenge in bioinformatics is the development of methods to accurately predict hot spots from protein sequences. In this paper, we combined existing methods into a meta-predictor for hot spots prediction, called MetAmyl for METapredictor for AMYLoid proteins. MetAmyl is based on a logistic regression model that aims at weighting predictions from a set of popular algorithms, statistically selected as being the most informative and complementary predictors. We evaluated the performances of MetAmyl through a large scale comparative study based on three independent datasets and thus demonstrated its ability to differentiate between amyloidogenic and non-amyloidogenic polypeptides. Compared to 9 other methods, MetAmyl provides significant improvement in prediction on studied datasets. We further show that MetAmyl is efficient to highlight the effect of point mutations involved in human amyloidosis, so we suggest this program should be a useful complementary tool for the diagnosis of these diseases.

  8. Apolipoprotein E: Essential Catalyst of the Alzheimer Amyloid Cascade

    Directory of Open Access Journals (Sweden)

    Huntington Potter

    2012-01-01

    Full Text Available The amyloid cascade hypothesis remains a robust model of AD neurodegeneration. However, amyloid deposits contain proteins besides Aβ, such as apolipoprotein E (apoE. Inheritance of the apoE4 allele is the strongest genetic risk factor for late-onset AD. However, there is no consensus on how different apoE isotypes contribute to AD pathogenesis. It has been hypothesized that apoE and apoE4 in particular is an amyloid catalyst or “pathological chaperone”. Alternatively it has been posited that apoE regulates Aβ clearance, with apoE4 been worse at this function compared to apoE3. These views seem fundamentally opposed. The former would indicate that removing apoE will reduce AD pathology, while the latter suggests increasing brain ApoE levels may be beneficial. Here we consider the scientific basis of these different models of apoE function and suggest that these seemingly opposing views can be reconciled. The optimal therapeutic target may be to inhibit the interaction of apoE with Aβ rather than altering apoE levels. Such an approach will not have detrimental effects on the many beneficial roles apoE plays in neurobiology. Furthermore, other Aβ binding proteins, including ACT and apo J can inhibit or promote Aβ oligomerization/polymerization depending on conditions and might be manipulated to effect AD treatment.

  9. AMYPdb: A database dedicated to amyloid precursor proteins

    Directory of Open Access Journals (Sweden)

    Delamarche Christian

    2008-06-01

    Full Text Available Abstract Background Misfolding and aggregation of proteins into ordered fibrillar structures is associated with a number of severe pathologies, including Alzheimer's disease, prion diseases, and type II diabetes. The rapid accumulation of knowledge about the sequences and structures of these proteins allows using of in silico methods to investigate the molecular mechanisms of their abnormal conformational changes and assembly. However, such an approach requires the collection of accurate data, which are inconveniently dispersed among several generalist databases. Results We therefore created a free online knowledge database (AMYPdb dedicated to amyloid precursor proteins and we have performed large scale sequence analysis of the included data. Currently, AMYPdb integrates data on 31 families, including 1,705 proteins from nearly 600 organisms. It displays links to more than 2,300 bibliographic references and 1,200 3D-structures. A Wiki system is available to insert data into the database, providing a sharing and collaboration environment. We generated and analyzed 3,621 amino acid sequence patterns, reporting highly specific patterns for each amyloid family, along with patterns likely to be involved in protein misfolding and aggregation. Conclusion AMYPdb is a comprehensive online database aiming at the centralization of bioinformatic data regarding all amyloid proteins and their precursors. Our sequence pattern discovery and analysis approach unveiled protein regions of significant interest. AMYPdb is freely accessible 1.

  10. Amyloid Goiter: A Diagnosis to Consider in Diffuse Fatty Infiltration of the Thyroid.

    Science.gov (United States)

    Bakan, Selim; Kandemirli, Sedat Giray; Akbas, Serkan; Cingoz, Mehmet; Ozcan Guzelbey, Burcu; Kantarci, Fatih; Akman, Canan

    2017-05-01

    An amyloid goiter is the presence of amyloid protein in the thyroid in sufficient amounts to produce enlargement of the gland, accompanied by fat deposition of varying extents. It can be seen in long-standing inflammatory disorders such as familial Mediterranean fever. Imaging findings depend on the amount of fat and amyloid deposition; however, the main imaging finding is diffuse fatty infiltration of the thyroid. Herein, the multimodality imaging features in 3 cases of amyloid goiters secondary to familial Mediterranean fever are presented. © 2017 by the American Institute of Ultrasound in Medicine.

  11. A Novel Liposomal Nanoparticle for the Imaging of Amyloid Plaque by Magnetic Resonance Imaging.

    Science.gov (United States)

    Tanifum, Eric A; Ghaghada, Ketan; Vollert, Craig; Head, Elizabeth; Eriksen, Jason L; Annapragada, Ananth

    2016-01-01

    Amyloid binding molecules with greater hydrophilicity than existing ligands were synthesized. The lead candidate ET6-21 bound amyloid fibrils, and amyloid deposits in dog brain and human brain tissue ex vivo. The ligand was used to prepare novel amyloid-targeted liposomal nanoparticles. The preparation was tested in the Tg2576 and TetO/APP mouse models of amyloid deposition. Gd chelates and Indocyanine green were included in the particles for visualization by MRI and near-infrared microscopy. Upon intravenous injection, the particles successfully traversed the blood-brain barrier in these mice, and bound to the plaques. Magnetic resonance imaging (T1-MRI) conducted 4 days after injection demonstrated elevated signal in the brains of mice with amyloid plaques present. No signal was observed in amyloid-negative mice, or in amyloid-positive mice injected with an untargeted version of the same agent. The MRI results were confirmed by immunohistochemical and fluorescent microscopic examination of mouse brain sections, showing colocalization of the fluorescent tags and amyloid deposits.

  12. Molecular understanding of a potential functional link between antimicrobial and amyloid peptides.

    Science.gov (United States)

    Zhang, Mingzhen; Zhao, Jun; Zheng, Jie

    2014-10-14

    Antimicrobial and amyloid peptides do not share common sequences, typical secondary structures, or normal biological activity but both the classes of peptides exhibit membrane-disruption ability to induce cell toxicity. Different membrane-disruption mechanisms have been proposed for antimicrobial and amyloid peptides, individually, some of which are not exclusive to either peptide type, implying that certain common principles may govern the folding and functions of different cytolytic peptides and associated membrane disruption mechanisms. Particularly, some antimicrobial and amyloid peptides have been identified to have dual complementary amyloid and antimicrobial properties, suggesting a potential functional link between amyloid and antimicrobial peptides. Given that some similar structural and membrane-disruption characteristics exist between the two classes of peptides, this review summarizes major findings, recent advances, and future challenges related to antimicrobial and amyloid peptides and strives to illustrate the similarities, differences, and relationships in the sequences, structures, and membrane interaction modes between amyloid and antimicrobial peptides, with a special focus on direct interactions of the peptides with the membranes. We hope that this review will stimulate further research at the interface of antimicrobial and amyloid peptides - which has been studied less intensively than either type of peptides - to decipher a possible link between both amyloid pathology and antimicrobial activity, which can guide drug design and peptide engineering to influence peptide-membrane interactions important in human health and diseases.

  13. [Clinical Laboratory Test Using Proteomics: The Usefulness of Proteomic Techniques for Amyloid Typing].

    Science.gov (United States)

    Tasaki, Masayoshi; Obayashi, Konen; Ando, Yukio

    2015-08-01

    Amyloidosis is a heterogeneous group of disorders characterized by the deposition of amyloid fibrils. To diagnose amyloidosis, it is important to detect amyloid deposits and identify the amyloid precursor protein in specimens, such as tissues and serum. Mass spectrometry is a powerful tool to measure the molecular weight and identify the protein. Recently, mass spectrometries such as liquid chromatography/tandem mass spectrometry and surface-enhanced laser desorption/ionization time of flight mass spectrometry, have made a contribution to amyloid typing. In the paper, we describe the usefulness of mass spectrometric analyses for the typing of amyloidosis.

  14. Calcium-dependent and -independent binding of the pentraxin serum amyloid P component to glycosaminoglycans and amyloid proteins

    DEFF Research Database (Denmark)

    Danielsen, B; Sørensen, I J; Nybo, Mads

    1997-01-01

    and beta2M) by ELISA. An increase in the dose-dependent binding of SAP to heparan sulfate, AA-protein and beta2M was observed as the pH decreased from 8.0 to 5.0. Furthermore, a lower, but significant Ca2(+)-independent binding of SAP to heparan sulfate, dermatan sulfate, AA protein and the amyloid...... precursor protein beta2M was observed. This binding was also enhanced at slightly acid pH, most pronounced at pH 5.0. The results of this study indicate that SAP can exhibit both Ca2(+)-dependent and -independent binding to ligands involved in amyloid fibril formation and that the binding is enhanced under...

  15. Paraneoplastic Progressive Vasculopathy as the Presenting Manifestation of Polyneuropathy, Organomegaly, Endocrinopathy or Edema, M-Spike, and Skin Manifestations: A Case Report.

    Science.gov (United States)

    Yaghi, Shadi; Elkind, Mitchell S V

    2016-07-01

    Polyneuropathy, organomegaly, endocrinopathy or edema, M-spike, and skin manifestations (POEMS) syndrome is a rare multisystem disease. There are very few reports of stroke as the presenting manifestation of POEMS. We report a patient with ischemic stroke due to an underlying vasculopathy as the initial presentation of POEMS. This case highlights the importance of recognizing ischemic stroke as a presenting sign for POEMS as early diagnosis and treatment in patients with POEMS may prevent progression of multisystem involvement and may potentially stabilize the vasculopathy associated with it. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  16. Innate Immunity Stimulation via Toll-Like Receptor 9 Ameliorates Vascular Amyloid Pathology in Tg-SwDI Mice with Associated Cognitive Benefits.

    Science.gov (United States)

    Scholtzova, Henrieta; Do, Eileen; Dhakal, Shleshma; Sun, Yanjie; Liu, Shan; Mehta, Pankaj D; Wisniewski, Thomas

    2017-01-25

    Alzheimer's disease (AD) is characterized by the presence of parenchymal amyloid-β (Aβ) plaques, cerebral amyloid angiopathy (CAA) and neurofibrillary tangles. Currently there are no effective treatments for AD. Immunotherapeutic approaches under development are hampered by complications related to ineffectual clearance of CAA. Genome-wide association studies have demonstrated the importance of microglia in AD pathogenesis. Microglia are the primary innate immune cells of the brain. Depending on their activation state and environment, microglia can be beneficial or detrimental. In our prior work, we showed that stimulation of innate immunity with Toll-like receptor 9 agonist, class B CpG (cytosine-phosphate-guanine) oligodeoxynucleotides (ODNs), can reduce amyloid and tau pathologies without causing toxicity in Tg2576 and 3xTg-AD mouse models. However, these transgenic mice have relatively little CAA. In the current study, we evaluated the therapeutic profile of CpG ODN in a triple transgenic mouse model, Tg-SwDI, with abundant vascular amyloid, in association with low levels of parenchymal amyloid deposits. Peripheral administration of CpG ODN, both before and after the development of CAA, negated short-term memory deficits, as assessed by object-recognition tests, and was effective at improving spatial and working memory evaluated using a radial arm maze. These findings were associated with significant reductions of CAA pathology lacking adverse effects. Together, our extensive evidence suggests that this innovative immunomodulation may be a safe approach to ameliorate all hallmarks of AD pathology, supporting the potential clinical applicability of CpG ODN. Recent genetic studies have underscored the emerging role of microglia in Alzheimer's disease (AD) pathogenesis. Microglia lose their amyloid-β-clearing capabilities with age and as AD progresses. Therefore, the ability to modulate microglia profiles offers a promising therapeutic avenue for reducing AD

  17. In vivo detection of amyloid plaques by gadolinium-stained MRI can be used to demonstrate the efficacy of an anti-amyloid immunotherapy

    Directory of Open Access Journals (Sweden)

    Mathieu D. Santin

    2016-03-01

    Full Text Available Extracellular deposition of β amyloid plaques is an early event associated to Alzheimer's disease. Here we have used in vivo gadolinium-stained high resolution (29*29*117µm3 MRI to follow-up in a longitudinal way individual amyloid plaques in APP/PS1 mice and evaluate the efficacy of a new immunotherapy (SAR255952 directed against protofibrillar and fibrillary forms of Aβ. APP/PS1 mice were treated for 5 months between the age of 3.5 and 8.5 months. SAR255952 reduced amyloid load in 8.5-month-old animals, but not in 5.5-month animals compared to mice treated with a control antibody (DM4. Histological evaluation confirmed the reduction of amyloid load and revealed a lower density of amyloid plaques in 8.5-month SAR255952-treated animals. The longitudinal follow-up of individual amyloid plaques by MRI revealed that plaques that were visible at 5.5 months were still visible at 8.5 months in both SAR255952 and DM4-treated mice. This suggests that the amyloid load reduction induced by SAR255952 is related to a slowing down in the formation of new plaques rather than to the clearance of already formed plaques.

  18. Ipomoea batatas attenuates amyloid β peptide-induced neurotoxicity in ICR mice.

    Science.gov (United States)

    Kim, Jae Kyeom; Choi, Soo Jung; Cho, Hong Yon; Kim, Young Jun; Lim, Seung-Taik; Kim, Chang-Ju; Kim, Eun Ki; Kim, Hye Kyung; Peterson, Sabrina; Shin, Dong-Hoon

    2011-03-01

    In this study, the protective effects of 17 Korean native plants against amyloid β peptide (Aβ)-induced oxidative stress were screened using the 2',7'-dichlorofluorescin diacetate assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Ipomoea batatas exerted the highest protective effects against oxidative stress and was selected for further investigation. To confirm the protective activity of this extract, the I. batatas extract was fed to ICR mice that had been injected with Aβ to induce neuronal deficits. In these experiments, the extract of I. batatas significantly reversed Aβ-induced neurotoxicity as assessed by the passive avoidance test, a behavioral experiment. Moreover, I. batatas administration reduced the level of lipid peroxidation and increased catalase activities in biochemical studies using the brain tissue of mice. These results indicate that I. batatas might be beneficial against Alzheimer's disease, especially by limiting oxidative stress in the brain.

  19. Smart Soup, a traditional Chinese medicine formula, ameliorates amyloid pathology and related cognitive deficits.

    Directory of Open Access Journals (Sweden)

    Yujun Hou

    Full Text Available Alzheimer's disease (AD is a progressive neurodegenerative disease that causes substantial public health care burdens. Intensive efforts have been made to find effective and safe disease-modifying treatment and symptomatic intervention alternatives against AD. Smart Soup (SS, a Chinese medicine formula composed of Rhizoma Acori Tatarinowii (AT, Poria cum Radix Pini (PRP and Radix Polygalae (RP, is a typical prescription against memory deficits. Here, we assessed the efficacy of SS against AD. Oral administration of SS ameliorated the cognitive impairment of AD transgenic mice, with reduced Aβ levels, retarded Aβ amyloidosis and reduced Aβ-induced gliosis and n