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1.
bioRxiv ; 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36993242

RESUMO

Phase transitions of cellular proteins and lipids play a key role in governing the organisation and coordination of intracellular biology. The frequent juxtaposition of proteinaceous biomolecular condensates to cellular membranes raises the intriguing prospect that phase transitions in proteins and lipids could be co-regulated. Here we investigate this possibility in the ribonucleoprotein (RNP) granule-ANXA11-lysosome ensemble, where ANXA11 tethers RNP granule condensates to lysosomal membranes to enable their co-trafficking. We show that changes to the protein phase state within this system, driven by the low complexity ANXA11 N-terminus, induce a coupled phase state change in the lipids of the underlying membrane. We identify the ANXA11 interacting proteins ALG2 and CALC as potent regulators of ANXA11-based phase coupling and demonstrate their influence on the nanomechanical properties of the ANXA11-lysosome ensemble and its capacity to engage RNP granules. The phenomenon of protein-lipid phase coupling we observe within this system offers an important template to understand the numerous other examples across the cell whereby biomolecular condensates closely juxtapose cell membranes.

2.
Clin Endocrinol (Oxf) ; 98(2): 221-228, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36161316

RESUMO

OBJECTIVE: To investigate the impact of musculoskeletal (MSK)-related symptoms on the quality of life of patients with multiple endocrine neoplasia Type 2b (MEN2B). DESIGN: An online survey was distributed by the Association for Multiple Endocrine Neoplasia Disorders (AMEND) to their members and worldwide via a social media group for MEN2B patients. METHODS: The survey consisted of a detailed questionnaire analysing the MSK-related symptoms and structural deformities of MEN2B patients and their impact on patient's lives. PARTICIPANTS: Forty-eight participants completed the survey. RESULTS: Participants reported several musculoskeletal complaints; the most prevalent being musculoskeletal weakness at 73% (n = 35) and pain 58% (n = 28). The median pain score was 7 (interquartile range [IQR]: 5-8) and the frequency of pain was daily in 44% (n = 15) and constant in 21% (n = 7). Structural complaints were common with 63% (n = 30) stating their physique was 'different' and 40% (n = 19) describing marfanoid body features. Spinal curvature and foot deformities were the commonest structural abnormalities with scoliosis 70% (n = 16) and pes cavus 63% (n = 22) prevailing. Dental problems were mentioned by 69% (n = 33) with interdental spacing being the most common complaint at 61% (n = 20). The musculoskeletal symptoms of MEN2B had a median impact of 6 (IQR: 3-9) on quality of life (QOL) with structural deformities 53% (n = 18) and pain 26% (n = 9) listed as having the highest impact. Poor MSK health affected exercise, work and mobility. CONCLUSIONS: We report a high prevalence of musculoskeletal-related complaints in MEN2B which significantly affects QOL. This suggests a need to provide better holistic care including a multidisciplinary team with physiotherapist, orthopaedic and dental specialist input.


Assuntos
Neoplasia Endócrina Múltipla Tipo 2b , Humanos , Neoplasia Endócrina Múltipla Tipo 2b/diagnóstico , Qualidade de Vida , Dor , Proteínas Proto-Oncogênicas c-ret
3.
J Alzheimers Dis ; 69(1): 91-109, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30909239

RESUMO

BACKGROUND: Genetic factors that influence Alzheimer's disease (AD) risk include mutations in TREM2 and allelic variants of Apolipoprotein E, influencing AD pathology in the general population and in Down syndrome (DS). Evidence shows that dysfunction of the choroid plexus may compromise the blood-cerebrospinal fluid (CSF) barrier, altering secretary, transport and immune function that can affect AD pathology. OBJECTIVE: To investigate the genotype and phenotype of DS individuals in relation to choroid plexus damage and blood-CSF barrier leakage to identify markers that could facilitate early diagnosis of AD in DS. METHODS: To assess allele frequency and haplotype associations ApoE, Tau, TREM2, and HLA-DR were analyzed by SNP analysis in DS participants (n = 47) and controls (n = 50). The corresponding plasma protein levels were measured by ELISA. Postmortem brains from DS, AD, and age-matched controls were analyzed by immunohistochemistry. RESULTS: Haplotype analysis showed that individuals with Tau H1/H1 and ApoEɛ4 genotypes were more prevalent among DS participants with an earlier diagnosis of dementia (17%) compared to H1/H2 haplotypes (6%). Plasma TREM2 levels decreased whereas phospho-tau levels increased with age in DS. In AD and DS brain, insoluble tau and ApoE were found to accumulate in the choroid plexus. CONCLUSION: Accumulation of tau and ApoE in the choroid plexus may increase the oligomerization rate of Aß42 and impair tau trafficking, leading to AD pathology. We have identified a high-risk haplotype: ApoEɛ4, Tau/H1, and TREM2/T, that manifests age-related changes potentially opening a window for treatment many years prior to the manifestation of the AD dementia.


Assuntos
Doença de Alzheimer/metabolismo , Apolipoproteínas E/metabolismo , Plexo Corióideo/metabolismo , Demência/metabolismo , Síndrome de Down/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo , Proteínas tau/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação
4.
J Alzheimers Dis ; 61(3): 1143-1162, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29278889

RESUMO

BACKGROUND: Down syndrome (DS; trisomy 21) individuals have a spectrum of hematopoietic and neuronal dysfunctions and by the time they reach the age of 40 years, almost all develop Alzheimer's disease (AD) neuropathology which includes senile plaques and neurofibrillary tangles. Inflammation and innate immunity are key players in AD and DS. Triggering receptor expressed in myeloid cells-2 (TREM2) variants have been identified as risk factors for AD and other neurodegenerative diseases. OBJECTIVE: To investigate the effects of TREM2 and the AD-associated R47H mutation on brain pathology and hematopoietic state in AD and DS. METHODS: We analyzed peripheral blood, bone marrow, and brain tissue from DS, AD, and age-matched control subjects by immunohistochemistry and western blotting. TREM2-related phagocytosis was investigated using a human myeloid cell line. RESULTS: TREM2 protein levels in brain and sera declined with age and disease progression in DS. We observed soluble TREM2 in brain parenchyma that may be carried by a subset of microglia, macrophages, or exosomes. Two DS cases had the AD-associated TREM2-R47H mutation, which manifested a morphologically extreme phenotype of megakaryocytes and erythrocytes in addition to impaired trafficking of TREM2 to the erythroid membrane. TREM2 was shown to be involved in phagocytosis of red blood cells. TREM2 was seen in early and late endosomes. Silencing TREM2 using siRNA in THP1 cells resulted in significant cell death. CONCLUSION: We provide evidence that peripheral TREM2 originating from erythromyeloid cells significantly determines AD neuropathology in DS subjects. Understanding the molecular signaling pathways mediated by TREM2 may reveal novel therapeutic targets.


Assuntos
Doença de Alzheimer/genética , Encéfalo/patologia , Síndrome de Down/complicações , Glicoproteínas de Membrana/genética , Receptores Imunológicos/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Linhagem Celular , Progressão da Doença , Exossomos , Feminino , Humanos , Imunidade Inata , Macrófagos/metabolismo , Masculino , Microglia/metabolismo , Pessoa de Meia-Idade , Fagocitose , Polimorfismo de Nucleotídeo Único
5.
J Alzheimers Dis ; 55(1): 199-217, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27662313

RESUMO

Neuroinflammation and activation of innate immunity are early events in neurodegenerative diseases including Alzheimer's disease (AD). Recently, a rare mutation in the gene Triggering receptor expressed on myeloid cells 2 (TREM2) has been associated with a substantial increase in the risk of developing late onset AD. To uncover the molecular mechanisms underlying this association, we investigated the RNA and protein expression of TREM2 in APP/PS1 transgenic mice. Our findings suggest that TREM2 not only plays a critical role in inflammation, but is also involved in neuronal cell survival and in neurogenesis. We have shown that TREM2 is a soluble protein transported by macrophages through ventricle walls and choroid plexus, and then enters the brain parenchyma via radial glial cells. TREM2 protein is essential for neuroplasticity and myelination. During the late stages of life, a lack of TREM2 protein may accelerate aging processes and neuronal cell loss and reduce microglial activity, ultimately leading to neuroinflammation. As inflammation plays a major role in neurodegenerative diseases, a lack of TREM2 could be a missing link between immunomodulation and neuroprotection.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Glicoproteínas de Membrana/metabolismo , Neuroproteção/fisiologia , Receptores Imunológicos/metabolismo , Envelhecimento/patologia , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/patologia , Células Cultivadas , Humanos , Lipopolissacarídeos , Macrófagos/metabolismo , Macrófagos/patologia , Meninges/metabolismo , Meninges/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Microglia/patologia , Neurogênese/fisiologia , Neurônios/metabolismo , Neurônios/patologia , Presenilina-1/genética , Presenilina-1/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
6.
Pharmacoeconomics ; 25(5): 355-63, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17488135

RESUMO

Pharmaceutical patents are anachronistic holdovers from an era in which modern economic understanding and tax tools were unavailable. Superior mechanisms lie somewhere between a first best pricing solution for the entire economy at one extreme and the current arrangements at the other. We discuss the economics of suggested alternatives and suggest that the intertemporal bounty is the best way to meet the multiple objectives of immediate distribution at marginal cost pricing of newly innovated patented drugs and easily administered, efficient inducement to continued innovation. The intertemporal bounty prevents the expansion of monopoly power resulting from co-pay or -insurance provisions common to modern prescription drug plans.


Assuntos
Indústria Farmacêutica/economia , Patentes como Assunto/legislação & jurisprudência , Preparações Farmacêuticas/economia , Legislação de Medicamentos/tendências , Modelos Econômicos , Pesquisa
7.
Expert Rev Pharmacoecon Outcomes Res ; 4(3): 287-96, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19807311

RESUMO

Despite its low incidence in the developed world, cervical cancer is the second most common cancer among women worldwide and the third most common cause of cancer-related deaths. Screening saves lives. When diagnosed and treated in the preinvasive stage, 5-year survival probabilities approach 100%. This review addresses the cost-effectiveness of the various screening strategies commonly used worldwide. The starting age of screening, interval between screens and age of women at cessation of screening are the most important variables determining cost-effectiveness. While the traditional Pap test is still the most cost-effective screening method in most settings, human papillomavirus testing can improve outcomes at reasonable costs in certain high-risk populations.

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