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Bowles KR, Silva MC, Whitney K, Bertucci T, Berlind JE, Lai JD, Garza JC, Boles NC, Mahali S, Strang KH, Marsh JA, Chen C, Pugh DA, Liu Y, Gordon RE, Goderie SK, Chowdhury R, Lotz S, Lane K, Crary JF, Haggarty SJ, Karch CM, Ichida JK, Goate AM, Temple S. ELAVL4, splicing, and glutamatergic dysfunction precede neuron loss in MAPT mutation cerebral organoids. Cell 2021; 184:4547-4563.e17. [PMID: 34314701 PMCID: PMC8635409 DOI: 10.1016/j.cell.2021.07.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/06/2021] [Accepted: 06/30/2021] [Indexed: 12/21/2022]
Abstract
Frontotemporal dementia (FTD) because of MAPT mutation causes pathological accumulation of tau and glutamatergic cortical neuronal death by unknown mechanisms. We used human induced pluripotent stem cell (iPSC)-derived cerebral organoids expressing tau-V337M and isogenic corrected controls to discover early alterations because of the mutation that precede neurodegeneration. At 2 months, mutant organoids show upregulated expression of MAPT, glutamatergic signaling pathways, and regulators, including the RNA-binding protein ELAVL4, and increased stress granules. Over the following 4 months, mutant organoids accumulate splicing changes, disruption of autophagy function, and build-up of tau and P-tau-S396. By 6 months, tau-V337M organoids show specific loss of glutamatergic neurons as seen in individuals with FTD. Mutant neurons are susceptible to glutamate toxicity, which can be rescued pharmacologically by the PIKFYVE kinase inhibitor apilimod. Our results demonstrate a sequence of events that precede neurodegeneration, revealing molecular pathways associated with glutamate signaling as potential targets for therapeutic intervention in FTD.
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Bomfim EMS, Coelho AAOP, Silva MC, Marques EJ, Vale VLC. Phytochemical composition and biological activities of extracts from ten species of the family Melastomataceae Juss. BRAZ J BIOL 2021; 82:e242112. [PMID: 34133563 DOI: 10.1590/1519-6984.242112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 11/22/2020] [Indexed: 11/22/2022] Open
Abstract
Plants possess a renewable source of metabolites with enormous chemical structural diversity, which may have potential therapeutic relevance. Furthermore, this chemical diversity favors the possibility of finding new and different chemical constituents with antimicrobial, antioxidant and anti-tumor activities. This work analyzed preliminary phytochemical profiles and evaluated the antimicrobial, antioxidant and cytotoxic activities of hexane extracts of leaves of ten species of the family Melastomataceae. Phytochemical screening was performed using staining methods while total phenols and flavonoids were quantified by spectrophotometry. Antimicrobial activity was evaluated using the disk diffusion method. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazil (DPPH) method. Toxicity was recorded using the lethality test with Artemia salina Leach (1819). Cytotoxic activity of the extracts was assessed in vitro with acute monocytic leukemia cells (THP-1). Phytochemical analysis detected the presence of tannins, terpenes, steroids, polyphenols and flavonoids and the absence of alkaloids. Clidemia capitellata (Bonpl.) D. Don had the greatest amount of polyphenols (205.95 mg/g ± 4.14) while Clidemia hirta (L.) D. Don had the highest content of total flavonoids (143.99 mg/g ± 4.18). The hexane extracts did not show antimicrobial activity nor toxicity against Artemia salina. The extract of Tibouchina francavillana Cogn. was the most active in sequestering the DPPH radical. The extracts showed cytotoxicity in THP-1 cells with the appearance of apoptotic bodies and cell death. The extracts of Miconia amoena, Clidemia sericea and Clidemia capitellata are non-toxic against Artemia salina and induce the formation of apoptotic bodies and cell death of the THP-1 lineage.
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Patnaik D, Pao PC, Zhao WN, Silva MC, Hylton NK, Chindavong PS, Pan L, Tsai LH, Haggarty SJ. Exifone Is a Potent HDAC1 Activator with Neuroprotective Activity in Human Neuronal Models of Neurodegeneration. ACS Chem Neurosci 2021; 12:271-284. [PMID: 33417763 DOI: 10.1021/acschemneuro.0c00308] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Genomic instability caused by a deficiency in the DNA damage response and repair has been linked to age-related cognitive decline and neurodegenerative diseases. Preventing genomic instability that ultimately leads to neuronal death may provide a broadly effective strategy to protect against multiple potential genotoxic stressors. Recently, the zinc-dependent class I histone deacetylase (HDAC1) has been identified as a critical factor for protecting neurons from deleterious effects of DNA damage in Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and frontotemporal dementia (FTD). Translating these observations to a novel neuroprotective therapy for AD, ALS, and FTD may be advanced by the identification of small molecules capable of increasing the deacetylase activity of HDAC1 selectively over other structurally similar HDACs. Here, we demonstrate that exifone, a drug previously shown to be effective in treating cognitive deficits associated with AD and Parkinson's disease, the molecular mechanism of which has remained poorly understood, potently activates the deacetylase activity of HDAC1. We show that exifone acts as a mixed, nonessential activator of HDAC1 that is capable of binding to both free and substrate-bound enzyme, resulting in an increased relative maximal rate of HDAC1-catalyzed deacetylation. Exifone can directly bind to HDAC1 based upon biolayer interferometry assays with kinetic and selectivity profiling, suggesting that HDAC1 is preferentially targeted compared to other class I HDACs and the kinase CDK5, which have also been implicated in neurodegeneration. Consistent with a mechanism of deacetylase activation intracellularly, the treatment of human induced pluripotent stem cell (iPSC)-derived neuronal cells resulted in globally decreased histone acetylation. Moreover, exifone treatment was neuroprotective in a tauopathy patient iPSC-derived neuronal model subject to oxidative stress. Taken together, these findings reveal exifone as a potent activator of HDAC1-mediated deacetylation, thereby offering a lead for novel therapeutic development aiming to protect genomic integrity in the context of neurodegeneration and aging.
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Silva MC, Haggarty SJ. Tauopathies: Deciphering Disease Mechanisms to Develop Effective Therapies. Int J Mol Sci 2020; 21:ijms21238948. [PMID: 33255694 PMCID: PMC7728099 DOI: 10.3390/ijms21238948] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/20/2020] [Accepted: 11/22/2020] [Indexed: 12/13/2022] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by the pathological accumulation of microtubule-associated protein tau (MAPT) in the form of neurofibrillary tangles and paired helical filaments in neurons and glia, leading to brain cell death. These diseases include frontotemporal dementia (FTD) and Alzheimer's disease (AD) and can be sporadic or inherited when caused by mutations in the MAPT gene. Despite an incredibly high socio-economic burden worldwide, there are still no effective disease-modifying therapies, and few tau-focused experimental drugs have reached clinical trials. One major hindrance for therapeutic development is the knowledge gap in molecular mechanisms of tau-mediated neuronal toxicity and death. For the promise of precision medicine for brain disorders to be fulfilled, it is necessary to integrate known genetic causes of disease, i.e., MAPT mutations, with an understanding of the dysregulated molecular pathways that constitute potential therapeutic targets. Here, the growing understanding of known and proposed mechanisms of disease etiology will be reviewed, together with promising experimental tau-directed therapeutics, such as recently developed tau degraders. Current challenges faced by the fields of tau research and drug discovery will also be addressed.
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Vieira-Neta MRA, Soares-da-Silva J, Viana JL, Silva MC, Tadei WP, Pinheiro VCS. Strain of Bacillus thuringiensis from Restinga, toxic to Aedes (Stegomyia) aegypti (Linnaeus) (Diptera, Culicidae). BRAZ J BIOL 2020; 81:872-880. [PMID: 33053121 DOI: 10.1590/1519-6984.228790] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 04/20/2020] [Indexed: 11/22/2022] Open
Abstract
Bacillus thuringiensis is the most commonly used entomopathogen in the control of Aedes aegypti, which is a vector for different etiological agents that cause serious infections in humans. Several studies aim to isolate strains of this bacterium from different environments, with the perspective of selecting isolates with larvicidal activity for mosquitoes. Aiming at the insecticidal action of B. thuringiensis, the present study aimed to prospect B. thuringiensis of restinga and mangrove soils from the state of Maranhão, Brazil, with toxic potential for use in the biological control of Ae. aegypti. Bioassays were performed to determine the entomopathogenic activity of the bacilli against Ae. aegypti and lethal concentrations (LC50 and CL90) were estimated after the tests. Polymerase Chain Reaction and SDS-PAGE techniques were performed to verify the gene and protein content of the isolates, respectively. The soil of the mangrove and restinga ecosystems showed potential for obtaining B. thuringiensis. This isolate, in addition to having proteins with molecular mass similar to the toxins Cry and Cyt, also presented several diptera-specific genes cry and cyt, demonstrating that it has high potential to be used in the biological control of Ae. aegypti.
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Silva MC, Haggarty SJ. Human pluripotent stem cell-derived models and drug screening in CNS precision medicine. Ann N Y Acad Sci 2020; 1471:18-56. [PMID: 30875083 PMCID: PMC8193821 DOI: 10.1111/nyas.14012] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 01/02/2019] [Accepted: 01/07/2019] [Indexed: 12/12/2022]
Abstract
Development of effective therapeutics for neurological disorders has historically been challenging partly because of lack of accurate model systems in which to investigate disease etiology and test new therapeutics at the preclinical stage. Human stem cells, particularly patient-derived induced pluripotent stem cells (iPSCs) upon differentiation, have the ability to recapitulate aspects of disease pathophysiology and are increasingly recognized as robust scalable systems for drug discovery. We review advances in deriving cellular models of human central nervous system (CNS) disorders using iPSCs along with strategies for investigating disease-relevant phenotypes, translatable biomarkers, and therapeutic targets. Given their potential to identify novel therapeutic targets and leads, we focus on phenotype-based, small-molecule screens employing human stem cell-derived models. Integrated efforts to assemble patient iPSC-derived cell models with deeply annotated clinicopathological data, along with molecular and drug-response signatures, may aid in the stratification of patients, diagnostics, and clinical trial success, shifting translational science and precision medicine approaches. A number of remaining challenges, including the optimization of cost-effective, large-scale culture of iPSC-derived cell types, incorporation of aging into neuronal models, as well as robustness and automation of phenotypic assays to support quantitative drug efficacy, toxicity, and metabolism testing workflows, are covered. Continued advancement of the field is expected to help fully humanize the process of CNS drug discovery.
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Silva MC, Nandi GA, Tentarelli S, Gurrell IK, Jamier T, Lucente D, Dickerson BC, Brown DG, Brandon NJ, Haggarty SJ. Prolonged tau clearance and stress vulnerability rescue by pharmacological activation of autophagy in tauopathy neurons. Nat Commun 2020; 11:3258. [PMID: 32591533 PMCID: PMC7320012 DOI: 10.1038/s41467-020-16984-1] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 05/30/2020] [Indexed: 12/27/2022] Open
Abstract
Tauopathies are neurodegenerative diseases associated with accumulation of abnormal tau protein in the brain. Patient iPSC-derived neuronal cell models replicate disease-relevant phenotypes ex vivo that can be pharmacologically targeted for drug discovery. Here, we explored autophagy as a mechanism to reduce tau burden in human neurons and, from a small-molecule screen, identify the mTOR inhibitors OSI-027, AZD2014 and AZD8055. These compounds are more potent than rapamycin, and robustly downregulate phosphorylated and insoluble tau, consequently reducing tau-mediated neuronal stress vulnerability. MTORC1 inhibition and autophagy activity are directly linked to tau clearance. Notably, single-dose treatment followed by washout leads to a prolonged reduction of tau levels and toxicity for 12 days, which is mirrored by a sustained effect on mTORC1 inhibition and autophagy. This new insight into the pharmacodynamics of mTOR inhibitors in regulation of neuronal autophagy may contribute to development of therapies for tauopathies.
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Grom LC, Rocha RS, Balthazar CF, Guimarães JT, Coutinho NM, Barros CP, Pimentel TC, Venâncio EL, Collopy Junior I, Maciel PMC, Silva PHF, Granato D, Freitas MQ, Esmerino EA, Silva MC, Cruz AG. Postprandial glycemia in healthy subjects: Which probiotic dairy food is more adequate? J Dairy Sci 2019; 103:1110-1119. [PMID: 31785881 DOI: 10.3168/jds.2019-17401] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/07/2019] [Indexed: 02/02/2023]
Abstract
The consumption of probiotic-enriched dairy products has been associated with many health benefits, including anti-hyperglycemic activity. The effect on health is dependent on the type of probiotic culture used and the dairy product consumed. This study evaluated the effect of different probiotic-enriched dairy matrices (Minas Frescal cheese, Prato cheese, and whey dairy beverage) containing Lactobacillus casei on in vitro and in vivo anti-hyperglycemic activity. For this purpose, in vitro anti-hyperglycemic activity was determined by the inhibition of α-glucosidase and α-amylase activities, and a human study was performed with healthy individuals (n = 15, consumption of bread as a control; bread + Minas Frescal cheese; bread + Prato cheese; bread + dairy beverage) to assess the effects of different probiotic foods on postprandial glycemia. In vitro data showed that Prato cheese presented the highest lipid (36.9 g/100 g) and protein (26.5 g/100 g) contents as well as the highest α-amylase (60.7%) and α-glucosidase (52.6%) inhibition. The consumption of Prato cheese resulted in a lesser increase in blood glucose level (13 mg/dL) compared with the consumption of bread alone (19 mg/dL), Minas Frescal cheese (20 mg/dL), and whey dairy beverage (30 mg/dL), with glycemic indices similar to that observed for the control. The present results demonstrated a good correlation between in vitro and in vivo data, in which the type of dairy matrix affects the anti-hyperglycemic activity. It is concluded that the consumption of probiotic Prato cheese can contribute to the reduction of postprandial glycemia in healthy individuals.
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Treichel CAS, Silva MC, Presotto RF, Onocko-Campos RT. Research Management Committee as strategic device for Implementation Research. Eur J Public Health 2019. [DOI: 10.1093/eurpub/ckz186.353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Issue/problem
Implementation Research (IR) are particularly useful in identifying whether when an intervention does not succeed, this is because the intervention was ineffective in the new scenario or if a good intervention was poorly implemented. In order to do this, it is important to establish evaluation strategies capable of provide feedback and encourage learning and incorporation of changes. However, the best strategies for this are not clear yet.
Description of the problem
Despite the existence of references with clear definitions of the outcomes for IR, it is still unclear what are the best strategies for the stakeholders’ participation in these outcomes evaluation. By identifying that, the framework of participatory research could contribute to the choice of these strategies. We sought to retrieve some of the devices already used in other research to test whether they would be able to respond to the assumptions of IR. The chosen device was the Research Management Committee (RMC) which has its use evaluated by a qualitative study with focus group and the data review of the minutes of meetings held by the RMC.
Results
The RMC functioned as a space where members of the research team, managers and workers from the services where the intervention occurred could meet systematically to plan, monitor and make adaptations in the IR. Besides its success as a tool for accessing outcomes, the RMC has also proved to be an important strategy to promote the increasing of acceptability, adoption, penetration and sustainability.
Lessons
The RMC was an important promoter of the participation for the stakeholders in several aspects of the research; made possible the evaluation and monitoring of the meaning and feasibility of the research in the field of study from the point of view of those who live the experience of daily work and care; and favored access to the outcomes of IR in a transversal and organic way.
Key messages
The RMC is a strategic device for Implementation Research and configures a possibility to make the research a more dialogic and potentially transformative process. Besides its success as a tool for accessing outcomes, the RMC has also proved to be an important strategy to promote the increasing of acceptability, adoption, penetration and sustainability.
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Karch CM, Kao AW, Karydas A, Onanuga K, Martinez R, Argouarch A, Wang C, Huang C, Sohn PD, Bowles KR, Spina S, Silva MC, Marsh JA, Hsu S, Pugh DA, Ghoshal N, Norton J, Huang Y, Lee SE, Seeley WW, Theofilas P, Grinberg LT, Moreno F, McIlroy K, Boeve BF, Cairns NJ, Crary JF, Haggarty SJ, Ichida JK, Kosik KS, Miller BL, Gan L, Goate AM, Temple S. A Comprehensive Resource for Induced Pluripotent Stem Cells from Patients with Primary Tauopathies. Stem Cell Reports 2019; 13:939-955. [PMID: 31631020 PMCID: PMC6895712 DOI: 10.1016/j.stemcr.2019.09.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 12/14/2022] Open
Abstract
Primary tauopathies are characterized neuropathologically by inclusions containing abnormal forms of the microtubule-associated protein tau (MAPT) and clinically by diverse neuropsychiatric, cognitive, and motor impairments. Autosomal dominant mutations in the MAPT gene cause heterogeneous forms of frontotemporal lobar degeneration with tauopathy (FTLD-Tau). Common and rare variants in the MAPT gene increase the risk for sporadic FTLD-Tau, including progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). We generated a collection of fibroblasts from 140 MAPT mutation/risk variant carriers, PSP, CBD, and cognitively normal controls; 31 induced pluripotent stem cell (iPSC) lines from MAPT mutation carriers, non-carrier family members, and autopsy-confirmed PSP patients; 33 genome engineered iPSCs that were corrected or mutagenized; and forebrain neural progenitor cells (NPCs). Here, we present a resource of fibroblasts, iPSCs, and NPCs with comprehensive clinical histories that can be accessed by the scientific community for disease modeling and development of novel therapeutics for tauopathies. A collection of fibroblasts from 140 MAPT mutation carriers, PSP, CBD, and controls 31 iPSC lines reprogrammed from MAPT mutation carriers, PSP patients, and controls 33 iPSC lines engineered with CRISPR/Cas9 or TALENs Comprehensive resource for tauopathy modeling and discovery of novel therapeutics
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Abreu A, Matos B, Silva C, Silva MC, Dias H, Amendoeira J, Silva M. P18 The influence of alcohol in the practice of safe sex in adolescence. Eur J Public Health 2019. [DOI: 10.1093/eurpub/ckz095.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Silva MC, Ferguson FM, Cai Q, Donovan KA, Nandi G, Patnaik D, Zhang T, Huang HT, Lucente DE, Dickerson BC, Mitchison TJ, Fischer ES, Gray NS, Haggarty SJ. Targeted degradation of aberrant tau in frontotemporal dementia patient-derived neuronal cell models. eLife 2019; 8:e45457. [PMID: 30907729 PMCID: PMC6450673 DOI: 10.7554/elife.45457] [Citation(s) in RCA: 161] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/23/2019] [Indexed: 12/11/2022] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by aberrant forms of tau protein accumulation leading to neuronal death in focal brain areas. Positron emission tomography (PET) tracers that bind to pathological tau are used in diagnosis, but there are no current therapies to eliminate these tau species. We employed targeted protein degradation technology to convert a tau PET-probe into a functional degrader of pathogenic tau. The hetero-bifunctional molecule QC-01-175 was designed to engage both tau and Cereblon (CRBN), a substrate-receptor for the E3-ubiquitin ligase CRL4CRBN, to trigger tau ubiquitination and proteasomal degradation. QC-01-175 effected clearance of tau in frontotemporal dementia (FTD) patient-derived neuronal cell models, with minimal effect on tau from neurons of healthy controls, indicating specificity for disease-relevant forms. QC-01-175 also rescued stress vulnerability in FTD neurons, phenocopying CRISPR-mediated MAPT-knockout. This work demonstrates that aberrant tau in FTD patient-derived neurons is amenable to targeted degradation, representing an important advance for therapeutics.
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Torres JA, Silva MC, Lopes JH, Nogueira AE, Nogueira FGE, Corrêa AD. Development of a reusable and sustainable biocatalyst by immobilization of soybean peroxidase onto magnetic adsorbent. Int J Biol Macromol 2018; 114:1279-1287. [PMID: 29578014 DOI: 10.1016/j.ijbiomac.2018.03.136] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 03/14/2018] [Accepted: 03/22/2018] [Indexed: 01/09/2023]
Abstract
In this work we synthesized an activated carbon/magnetite composite by a simple co-precipitation method. The activated carbon (AC) was synthesized from the solid waste obtained in the extraction process of the peroxidase enzyme and the magnetic composite was used as support for the immobilization of soybean peroxidase (SP). After the determination of the optimal immobilization parameters, a 100% yield was achieved under the following conditions: support:enzyme proportion of 1.0:0.05 g, equilibration time of 7 h, pH 3.0 (citrate buffer phosphate 0.1 mol L-1) and temperature of 50 °C. The determination of pH to the point of zero charge was also done to assist in the understanding of the immobilization process at different pH values. Several characterization techniques were used, such as thermogravimetric analysis, elemental analysis composition, X-ray powder diffraction, Fourier transform infrared spectroscopy and Scanning electron microscopy. The biocatalyst presented excellent operational stability and was reused for 11 consecutive cycles. The magnetic properties inserted in the AC contributed to the removal of the biocatalyst from the reaction medium without interfering in the adsorptive characteristics of the AC. Thus, the activated carbon/magnetite composite can be applied to different research fields with high performance.
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Silva LM, Silva MC, Silva SMFA, Alves RC, Siqueira HAA, Marques EJ. Toxin Gene Contents and Activity of Bacillus thuringiensis Strains Against Two Sugarcane Borer Species, Diatraea saccharalis (F.) and D. flavipennella (Box). NEOTROPICAL ENTOMOLOGY 2018; 47:292-301. [PMID: 28866859 DOI: 10.1007/s13744-017-0558-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 08/22/2017] [Indexed: 06/07/2023]
Abstract
Bacillus thuringiensis (Berliner) bears essential characteristics in the control of insect pests, such as its unique mode of action, which confers specificity and selectivity. This study assessed cry gene contents from Bt strains and their entomotoxicity against Diatraea saccharalis (F.) and Diatraea flavipennella (Box) (Lepidoptera: Crambidae). Bioassays with Bt strains were performed against neonates to evaluate their lethal and sublethal activities and were further analyzed by PCR, using primers to identify toxin genes. For D. saccharalis and D. flavipennella, 16 and 18 strains showed over 30% larval mortality in the 7th day, respectively. The LC50 values of strains for D. saccharalis varied from 0.08 × 105 (LIIT-0105) to 4104 × 105 (LIIT-2707) spores + crystals mL-1. For D. flavipennella, the LC50 values of strains varied from 0.40 × 105 (LIIT-2707) to 542 × 105 (LIIT-2109) spores + crystals mL-1. For the LIIT-0105 strain, which was the most toxic to D. saccharalis, the genes cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, cry8, and cry9C were detected, whereas for the strain LIIT-2707, which was the most toxic to D. flavipennella, detected genes were cry1Aa, cry1Ab, cry1Ac, cry1B, cry1D, cry1F, cry1I, cry2Aa, cry2Ab, and cry9. The toxicity data and toxin gene content in these strains of Bt suggest a great variability of activity with potential to be used in the development of novel biopesticides or as source of resistance genes that can be expressed in plants to control pests.
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Silva MC, Azevedo MA, Figueiredo VP, Moura Junior MR, Coelho Junior D, Martinelli PM, Machado RP, Alzamora AC, Talvani A. Renovascular hypertension increases serum TNF and CX3CL1 in experimental Trypanosoma cruzi infection. ACTA ACUST UNITED AC 2018; 51:e6690. [PMID: 29590257 PMCID: PMC5886554 DOI: 10.1590/1414-431x20186690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 01/22/2018] [Indexed: 11/22/2022]
Abstract
Trypanosoma cruzi triggers a progressive inflammatory response affecting cardiovascular functions in humans and experimental models. Angiotensin II, a key effector of the renin-angiotensin system, plays roles in mediating hypertension, heart failure, and inflammatory responses. T. cruzi and AngII can induce inflammatory responses by releasing inflammatory mediators. The aim of this study was to evaluate systemic AngII, tumor necrosis factor (TNF), and CX3CL1 mediators in a two-kidney one-clip (2K1C) renovascular hypertension model using Wistar rats infected with T. cruzi. Our data showed an increase in serum AngII in uninfected and T. cruzi-infected rats 1 week after 2K1C surgery compared to non-2K1C (Sham) animals. The baseline systolic blood pressure was higher in both uninfected and infected 2K1C rats. Despite no difference in circulating parasites in the acute phase of infection, elevated serum TNF and CX3CL1 were observed at 8 weeks post-infection in 2K1C rats in association with higher cardiac inflammatory infiltration. In summary, AngII-induced hypertension associated with T. cruzi infection may act synergistically to increase TNF and CX3CL1 in the 2K1C rat model, thereby intensifying cardiac inflammatory infiltration and worsening the underlying inflammation triggered by this protozoan.
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Quirino TF, Ferreira AJMG, Silva MC, Silva RJ, Morais DH, Ávila RW. New records of Helminths in Reptiles from five states of Brazil. BRAZ J BIOL 2018; 78:750-754. [PMID: 29489929 DOI: 10.1590/1519-6984.175745] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 05/18/2017] [Indexed: 11/21/2022] Open
Abstract
Forty five specimens representing nine species of reptile (Salvator merianae, Enyalius bilineatus, Amphisbaena alba, Xenopholis undulatus, Chironius fuscus, Helicops angulatus, Chironius flavolineatus, Erythrolamprus viridis and Crotalus durissus) collected in five Brazilian states were examined for helminths. Twelve helminth species were found as follow: nine Nematoda (Physaloptera tupinambae, Strongyluris oscari, Paracapillaria sp., Dracunculus brasiliensis, Physaloptera liophis, Serpentirhabias sp. 1, Serpentirhabias sp. 2, Serpentirhabias sp. 3 and Aplectana sp.), one Cestoda (Semenoviella amphisbaenia), one Trematoda (Paracotyletrema sp.), and one Acantocephala (Centrorhynchus sp.). Ten new host records and seven new locality records were reported.
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Boselli M, Lee BH, Robert J, Prado MA, Min SW, Cheng C, Silva MC, Seong C, Elsasser S, Hatle KM, Gahman TC, Gygi SP, Haggarty SJ, Gan L, King RW, Finley D. An inhibitor of the proteasomal deubiquitinating enzyme USP14 induces tau elimination in cultured neurons. J Biol Chem 2017; 292:19209-19225. [PMID: 28972160 DOI: 10.1074/jbc.m117.815126] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Indexed: 11/06/2022] Open
Abstract
The ubiquitin-proteasome system (UPS) is responsible for most selective protein degradation in eukaryotes and regulates numerous cellular processes, including cell cycle control and protein quality control. A component of this system, the deubiquitinating enzyme USP14, associates with the proteasome where it can rescue substrates from degradation by removal of the ubiquitin tag. We previously found that a small-molecule inhibitor of USP14, known as IU1, can increase the rate of degradation of a subset of proteasome substrates. We report here the synthesis and characterization of 87 variants of IU1, which resulted in the identification of a 10-fold more potent USP14 inhibitor that retains specificity for USP14. The capacity of this compound, IU1-47, to enhance protein degradation in cells was tested using as a reporter the microtubule-associated protein tau, which has been implicated in many neurodegenerative diseases. Using primary neuronal cultures, IU1-47 was found to accelerate the rate of degradation of wild-type tau, the pathological tau mutants P301L and P301S, and the A152T tau variant. We also report that a specific residue in tau, lysine 174, is critical for the IU1-47-mediated tau degradation by the proteasome. Finally, we show that IU1-47 stimulates autophagic flux in primary neurons. In summary, these findings provide a powerful research tool for investigating the complex biology of USP14.
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Balthazar CF, Silva HLA, Vieira AH, Neto RPC, Cappato LP, Coimbra PT, Moraes J, Andrade MM, Calado VMA, Granato D, Freitas MQ, Tavares MIB, Raices RSL, Silva MC, Cruz AG. Assessing the effects of different prebiotic dietary oligosaccharides in sheep milk ice cream. Food Res Int 2016; 91:38-46. [PMID: 28290325 DOI: 10.1016/j.foodres.2016.11.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 01/12/2023]
Abstract
The objective of this study was to assess the effects of different prebiotic dietary oligosaccharides (inulin, fructo-oligosaccharide, galacto-oligossacaride, short-chain fructo-oligosaccharide, resistant starch, corn dietary oligosaccharide and polydextrose) in non-fat sheep milk ice cream processing through physical parameters, water mobility and thermal analysis. Overall, the fat replacement by dietary prebiotic oligosaccharides significantly decreased the melting time, melting temperature and the fraction and relaxation time for fat and bound water (T22) while increased the white intensity and glass transition temperature. The replacement of sheep milk fat by prebiotics in sheep milk ice cream constitutes an interesting option to enhance nutritional aspects and develop a functional food.
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Moura CS, Lollo PCB, Morato PN, Esmerino EA, Margalho LP, Santos-Junior VA, Coimbra PT, Cappato LP, Silva MC, Garcia-Gomes AS, Granato D, Bolini HMA, Sant'Ana AS, Cruz AG, Amaya-Farfan J. Assessment of antioxidant activity, lipid profile, general biochemical and immune system responses of Wistar rats fed with dairy dessert containing Lactobacillus acidophilus La-5. Food Res Int 2016; 90:275-280. [PMID: 29195882 DOI: 10.1016/j.foodres.2016.10.042] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/24/2016] [Accepted: 10/24/2016] [Indexed: 12/11/2022]
Abstract
The viability and survival of Lactobacillus acidophilus La5 under in vitro simulated gastrointestinal in probiotic dairy dessert was assessed. In addition, the effects of regular consumption of the dessert (5g/day) on the lipid profile, immune system, and antioxidant/biochemical status of Wistar rats were also evaluated after 2weeks of treatment. Adequate counts of L. acidophilus La-5 were observed regards the viability and gastrointestinal conditions. The probiotic dairy dessert was efficient in reducing the LDL-cholesterol, triacylglycerol and increased the HDL-cholesterol in serum. Aspartate amino transferase, alanine aminotransferase, total protein, albumin, heat shock proteins, immune system responses, and blood-cells counts (monocyte, lymphocyte, neutrophil and leucocyte) were not affected (p>0.05) after 15days of treatment. Overall, the probiotic dairy dessert may be a viable alternative to enhance the blood lipid profile and could be used to improve the antioxidant defenses.
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Silva MC, Cheng C, Mair W, Almeida S, Fong H, Biswas MHU, Zhang Z, Huang Y, Temple S, Coppola G, Geschwind DH, Karydas A, Miller BL, Kosik KS, Gao FB, Steen JA, Haggarty SJ. Human iPSC-Derived Neuronal Model of Tau-A152T Frontotemporal Dementia Reveals Tau-Mediated Mechanisms of Neuronal Vulnerability. Stem Cell Reports 2016; 7:325-340. [PMID: 27594585 PMCID: PMC5032560 DOI: 10.1016/j.stemcr.2016.08.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 07/27/2016] [Accepted: 08/01/2016] [Indexed: 12/30/2022] Open
Abstract
Frontotemporal dementia (FTD) and other tauopathies characterized by focal brain neurodegeneration and pathological accumulation of proteins are commonly associated with tau mutations. However, the mechanism of neuronal loss is not fully understood. To identify molecular events associated with tauopathy, we studied induced pluripotent stem cell (iPSC)-derived neurons from individuals carrying the tau-A152T variant. We highlight the potential of in-depth phenotyping of human neuronal cell models for pre-clinical studies and identification of modulators of endogenous tau toxicity. Through a panel of biochemical and cellular assays, A152T neurons showed accumulation, redistribution, and decreased solubility of tau. Upregulation of tau was coupled to enhanced stress-inducible markers and cell vulnerability to proteotoxic, excitotoxic, and mitochondrial stressors, which was rescued upon CRISPR/Cas9-mediated targeting of tau or by pharmacological activation of autophagy. Our findings unmask tau-mediated perturbations of specific pathways associated with neuronal vulnerability, revealing potential early disease biomarkers and therapeutic targets for FTD and other tauopathies. Upregulation of tau and phospho-tau in FTD patient iPSC-derived tau A152T neurons Upregulation of insoluble tau in A152T neurons Altered proteostasis stress-inducible pathways in tau A152T neurons Tau-dependent vulnerability to stress in A152T neurons reverted by tau downregulation
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Silva MC, Siqueira HAA, Silva LM, Marques EJ, Barros R. Cry Proteins from Bacillus thuringiensis Active against Diamondback Moth and Fall Armyworm. NEOTROPICAL ENTOMOLOGY 2015; 44:392-401. [PMID: 26070631 DOI: 10.1007/s13744-015-0302-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 05/08/2015] [Indexed: 06/04/2023]
Abstract
Biopesticides based on Bacillus thuringiensis and genetically modified plants with genes from this bacterium have been used to control Plutella xylostella (L.) and Spodoptera frugiperda (J.E. Smith). However, the selection pressure imposed by these technologies may undermine the efficiency of this important alternative to synthetic insecticides. Toxins with different modes of action allow a satisfactory control of these insects. The purpose of this study was to characterize the protein and gene contents of 20 B. thuringiensis isolates from soil and insect samples collected in several areas of Northeast Brazil which are active against P. xylostella and S. frugiperda. Protein profiles were obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Polymerase chain reaction assays were used to determine toxin genes present within bacterial isolates. The protein profile of the majority of the isolates produced bands of approximately 130 kDa, suggesting the presence of Cry1, Cry8 and Cry9 proteins. The gene content of the isolates of B. thuringiensis investigated showed different gene profiles. Isolates LIIT-4306 and LIIT-4311 were the most actives against both species, with LC50 of 0.03 and 0.02 × 10(8) spores mL(-1), respectively, for P. xylostella, and LC50 of 0.001 × 10(8) spores mL(-1) for S. frugiperda. These isolates carried the cry1, cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C, cry1D, cry1F, cry2, cry2A, cry8, and cry9C genes. The obtained gene profiles showed great potential for the control of P. xylostella and S. frugiperda, primarily because of the presence of several cry1A genes, which are found in isolates of B. thuringiensis active against these insects.
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Godinho AF, Stanzani SL, Ferreira FC, Braga TC, Silva MC, Chaguri JL, Dias-Júnior CA. "Permethrin chronic exposure alters motor coordination in rats: effect of calcium supplementation and amlodipine". ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:878-884. [PMID: 24667353 DOI: 10.1016/j.etap.2014.02.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 02/21/2014] [Accepted: 02/24/2014] [Indexed: 06/03/2023]
Abstract
Recently was observed that pyrethroids decrease motor coordination and that calcium channels can be important targets for this effect. To contribute with this observation, this work studied the motor coordination and exploration (using hole-board apparatus), and locomotion (using open-field apparatus) of rats exposed to following treatments: permethrin (PM), PM plus calcium gluconate (CG) and PM plus amlodipine (AML). The results obtained show that CG or AML alone not changed the motor coordination while PM decreases it. CG kept the effect of permethrin; AML, however, decreased the values of permethrin to the control. Locomotor activity and exploration, which could confound results of motor coordination, were not modified by treatments. The concentration of PM in brain tissue was increased by the CG and AML. The neurosomatic index (weight brain/body weight) was increased by the PM and PM+CG. In conclusion, the combined results here obtained indicates that the calcium ion and the channels in which it is involved can be important targets for the toxic effect of pyrethroid insecticide permethrin on motor nerve activity of rats.
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Silva MC, Amaral MD, Morimoto RI. Neuronal reprograming of protein homeostasis by calcium-dependent regulation of the heat shock response. PLoS Genet 2013; 9:e1003711. [PMID: 24009518 PMCID: PMC3757039 DOI: 10.1371/journal.pgen.1003711] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 06/25/2013] [Indexed: 12/20/2022] Open
Abstract
Protein quality control requires constant surveillance to prevent misfolding, aggregation, and loss of cellular function. There is increasing evidence in metazoans that communication between cells has an important role to ensure organismal health and to prevent stressed cells and tissues from compromising lifespan. Here, we show in C. elegans that a moderate increase in physiological cholinergic signaling at the neuromuscular junction (NMJ) induces the calcium (Ca(2+))-dependent activation of HSF-1 in post-synaptic muscle cells, resulting in suppression of protein misfolding. This protective effect on muscle cell protein homeostasis was identified in an unbiased genome-wide screening for modifiers of protein aggregation, and is triggered by downregulation of gei-11, a Myb-family factor and proposed regulator of the L-type acetylcholine receptor (AChR). This, in-turn, activates the voltage-gated Ca(2+) channel, EGL-19, and the sarcoplasmic reticulum ryanodine receptor in response to acetylcholine signaling. The release of calcium into the cytoplasm of muscle cells activates Ca(2+)-dependent kinases and induces HSF-1-dependent expression of cytoplasmic chaperones, which suppress misfolding of metastable proteins and stabilize the folding environment of muscle cells. This demonstrates that the heat shock response (HSR) can be activated in muscle cells by neuronal signaling across the NMJ to protect proteome health.
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Ubiali DG, Cruz RAS, De Paula DAJ, Silva MC, Mendonça FS, Dutra V, Nakazato L, Colodel EM, Pescador CA. Pathology of nasal infection caused by Conidiobolus lamprauges and Pythium insidiosum in sheep. J Comp Pathol 2013; 149:137-45. [PMID: 23375916 DOI: 10.1016/j.jcpa.2012.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/04/2012] [Accepted: 12/05/2012] [Indexed: 10/27/2022]
Abstract
Conidiobolomycosis and pythiosis are important diseases of sheep in midwestern Brazil. Veterinary practitioners consider it difficult to differentiate between these diseases because they have similar clinical features. In this study, 186 sheep were subjected to necropsy examination over a 6-year period. Thirty (16.1%) cases of rhinitis in sheep that were caused by Conidiobolus lamprauges (n = 15) or Pythium insidiosum (n = 15) were investigated further. The lesions of C. lamprauges infection were mainly rhinopharyngeal (86.7%), localized to the ethmoidal region and associated with exophthalmos. The lesions appear as a white to yellow, firm mass that microscopically appears as a granulomatous inflammatory reaction with numerous giant cells. In contrast, P. insidiosum infection is associated with rhinofacial (93.3%) lesions that mainly involve the frontal region and hard palate and appear as an irregular, friable, yellow to red mass. Microscopically, pythiosis presents as diffuse necrotizing eosinophilic rhinitis. Immunohistochemistry using polyclonal antisera raised specifically against the two organisms was used to confirm the identity of the infectious agent in each disease. This study reports the first immunohistochemical diagnosis of conidiobolomycosis and the first description of a rhinopharyngeal lesion caused by P. insidiosum in sheep.
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Beam M, Silva MC, Morimoto RI. Dynamic imaging by fluorescence correlation spectroscopy identifies diverse populations of polyglutamine oligomers formed in vivo. J Biol Chem 2012; 287:26136-45. [PMID: 22669943 DOI: 10.1074/jbc.m112.362764] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein misfolding and aggregation are exacerbated by aging and diseases of protein conformation including neurodegeneration, metabolic diseases, and cancer. In the cellular environment, aggregates can exist as discrete entities, or heterogeneous complexes of diverse solubility and conformational state. In this study, we have examined the in vivo dynamics of aggregation using imaging methods including fluorescence microscopy, fluorescence recovery after photobleaching (FRAP), and fluorescence correlation spectroscopy (FCS), to monitor the diverse biophysical states of expanded polyglutamine (polyQ) proteins expressed in Caenorhabditis elegans. We show that monomers, oligomers and aggregates co-exist at different concentrations in young and aged animals expressing different polyQ-lengths. During aging, when aggregation and toxicity are exacerbated, FCS-based burst analysis and purified single molecule FCS detected a populational shift toward an increase in the frequency of brighter and larger oligomeric species. Regardless of age or polyQ-length, oligomers were maintained in a heterogeneous distribution that spans multiple orders of magnitude in brightness. We employed genetic suppressors that prevent polyQ aggregation and observed a reduction in visible immobile species with the persistence of heterogeneous oligomers, yet our analysis did not detect the appearance of any discrete oligomeric states associated with toxicity. These studies reveal that the reversible transition from monomers to immobile aggregates is not represented by discrete oligomeric states, but rather suggests that the process of aggregation involves a more complex pattern of molecular interactions of diverse intermediate species that can appear in vivo and contribute to aggregate formation and toxicity.
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