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While antibiotics are intended to specifically target bacteria, most are known to affect host cell physiology. In addition, some antibiotic classes are reported as immunosuppressive for reasons that remain unclear. Here, we show that Linezolid, a ribosomal-targeting antibiotic (RAbo), effectively blocked the course of a T cell-mediated autoimmune disease. Linezolid and other RAbos were strong inhibitors of T helper-17 cell effector function in vitro, showing that this effect was independent of their antibiotic activity. Perturbing mitochondrial translation in differentiating T cells, either with RAbos or through the inhibition of mitochondrial elongation factor G1 (mEF-G1) progressively compromised the integrity of the electron transport chain. Ultimately, this led to deficient oxidative phosphorylation, diminishing nicotinamide adenine dinucleotide concentrations and impairing cytokine production in differentiating T cells. In accordance, mice lacking mEF-G1 in T cells were protected from experimental autoimmune encephalomyelitis, demonstrating that this pathway is crucial in maintaining T cell function and pathogenicity.
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Antibacterianos/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Linezolida/uso terapêutico , Mitocôndrias/metabolismo , Peptídeos Cíclicos/uso terapêutico , Ribossomos/metabolismo , Células Th17/fisiologia , Animais , Autoimunidade/efeitos dos fármacos , Diferenciação Celular , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/genética , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Terapia de Alvo Molecular , Esclerose Múltipla/tratamento farmacológico , NAD/metabolismo , Fosforilação Oxidativa , Fator G para Elongação de Peptídeos/genética , Fator G para Elongação de Peptídeos/metabolismoRESUMO
Spinocerebellar ataxia type 3/Machado-Joseph disease is the most common autosomal dominant ataxia. In view of the development of targeted therapies, knowledge of early biomarker changes is needed. We analyzed cross-sectional data of 292 spinocerebellar ataxia type 3/Machado-Joseph disease mutation carriers. Blood concentrations of mutant ATXN3 were high before and after ataxia onset, whereas neurofilament light deviated from normal 13.3 years before onset. Pons and cerebellar white matter volumes decreased and deviated from normal 2.2 years and 0.6 years before ataxia onset. We propose a staging model of spinocerebellar ataxia type 3/Machado-Joseph disease that includes a biomarker stage characterized by objective indicators of neurodegeneration before ataxia onset. ANN NEUROL 2024;95:400-406.
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Ataxia Cerebelar , Doença de Machado-Joseph , Humanos , Doença de Machado-Joseph/genética , Estudos Transversais , Ataxia , BiomarcadoresRESUMO
Chronic stress exerts profound negative effects on cognitive and emotional behaviours and is a major risk factor for the development of neuropsychiatric disorders. However, the molecular links between chronic stress and its deleterious effects on neuronal and synaptic function remain elusive. Here, using a combination of in vitro and in vivo approaches, we demonstrate that the upregulation of miR-186-5p triggered by chronic stress may be a key mediator of such changes, leading to synaptic dysfunction. Our results show that the expression levels of miR-186-5p are increased both in the prefrontal cortex (PFC) of mice exposed to chronic stress and in cortical neurons chronically exposed to dexamethasone. Additionally, viral overexpression of miR-186-5p in the PFC of naïve mice induces anxiety- and depressive-like behaviours. The upregulation of miR-186-5p through prolonged glucocorticoid receptor activation in vitro, or in a mouse model of chronic stress, differentially affects glutamatergic and GABAergic synaptic transmission, causing an imbalance in excitation/inhibition that leads to altered neuronal network activity. At glutamatergic synapses, we observed both a reduction in synaptic AMPARs and synaptic transmission, whereas GABAergic synaptic transmission was strengthened. These changes could be rescued in vitro by a miR-186-5p inhibitor. Overall, our results establish a novel molecular link between chronic glucocorticoid receptor activation, the upregulation of miR-186-5p and the synaptic changes induced by chronic stress, that may be amenable to therapeutic intervention.
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Polyglutamine disorders are a complex group of incurable neurodegenerative disorders caused by an abnormal expansion in the trinucleotide cytosine-adenine-guanine tract of the affected gene. To better understand these disorders, our dependence on animal models persists, primarily relying on transgenic models. In an effort to complement and deepen our knowledge, researchers have also developed animal models of polyglutamine disorders employing viral vectors. Viral vectors have been extensively used to deliver genes to the brain, not only for therapeutic purposes but also for the development of animal models, given their remarkable flexibility. In a time- and cost-effective manner, it is possible to use different transgenes, at varying doses, in diverse targeted tissues, at different ages, and in different species, to recreate polyglutamine pathology. This paper aims to showcase the utility of viral vectors in disease modelling, share essential considerations for developing animal models with viral vectors, and provide a comprehensive review of existing viral-based animal models for polyglutamine disorders.
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Peptídeos , Expansão das Repetições de Trinucleotídeos , Animais , Peptídeos/genética , Modelos Animais de Doenças , TransgenesRESUMO
Spinocerebellar ataxia type 3 (SCA3)/Machado-Joseph disease (MJD) is a heritable proteinopathy disorder, whose causative gene, ATXN3, undergoes alternative splicing. Ataxin-3 protein isoforms differ in their toxicity, suggesting that certain ATXN3 splice variants may be crucial in driving the selective toxicity in SCA3. Using RNA-seq datasets we identified and determined the abundance of annotated ATXN3 transcripts in blood (n = 60) and cerebellum (n = 12) of SCA3 subjects and controls. The reference transcript (ATXN3-251), translating into an ataxin-3 isoform harbouring three ubiquitin-interacting motifs (UIMs), showed the highest abundance in blood, while the most abundant transcript in the cerebellum (ATXN3-208) was of unclear function. Noteworthy, two of the four transcripts that encode full-length ataxin-3 isoforms but differ in the C-terminus were strongly related with tissue expression specificity: ATXN3-251 (3UIM) was expressed in blood 50-fold more than in the cerebellum, whereas ATXN3-214 (2UIM) was expressed in the cerebellum 20-fold more than in the blood. These findings shed light on ATXN3 alternative splicing, aiding in the comprehension of SCA3 pathogenesis and providing guidance in the design of future ATXN3 mRNA-lowering therapies.
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Doença de Machado-Joseph , Humanos , Doença de Machado-Joseph/metabolismo , Ataxina-3/genética , Ataxina-3/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Cerebelo/patologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismoRESUMO
The root cause of sickle cell disease (SCD) has been known for nearly a century, however, few therapies to treat the disease are available. Over several decades of work, with advances in gene editing technology and after several iterations of mice with differing genotype/phenotype relationships, researchers have developed humanized SCD mouse models. However, while a large body of preclinical studies has led to huge gains in basic science knowledge about SCD in mice, this knowledge has not led to the development of effective therapies to treat SCD-related complications in humans, thus leading to frustration with the paucity of translational progress in the SCD field. The use of mouse models to study human diseases is based on the genetic and phenotypic similarities between mouse and humans (face validity). The Berkeley and Townes SCD mice express only human globin chains and no mouse hemoglobin. With this genetic composition, these models present many phenotypic similarities, but also significant discrepancies that should be considered when interpreting preclinical studies results. Reviewing genetic and phenotypic similarities and discrepancies and examining studies that have translated to humans and those that have not, offer a better perspective of construct, face, and predictive validities of humanized SCD mouse models.
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Anemia Falciforme , Camundongos , Humanos , Animais , Anemia Falciforme/genética , Anemia Falciforme/terapia , Anemia Falciforme/complicações , Modelos Animais de Doenças , HemoglobinasRESUMO
Red blood cells (RBC) from patients with sickle cell disease (SCD) have elevated calcium levels at baseline, which are further elevated upon deoxygenation. Here we examined baseline calcium levels and calcium flux in RBCs from a mouse model of SCD mice. We found that akin to humans with SCD, sickle (HbSS) Townes mice, have higher baseline levels and increased calcium flux in RBCs compared to control (HbAA) animals. As HbSS mice, unlike humans with SCD, have high mean corpuscular volume compared with HbAA, we highlight the importance of adjusting biochemical results to number of RBCs rather than hematocrit during the analysis and interpretation of the results. Our findings add to the face validity of humanized sickle cell mice and support its use for studies of RBC calcium flux in SCD.
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Anemia Falciforme , Índices de Eritrócitos , Humanos , Camundongos , Animais , Cálcio , Eritrócitos , Eritrócitos Anormais , Hemoglobina Falciforme/genéticaRESUMO
In recentin vitroexperiments on co-culture between breast tumour spheroids and activated immune cells, it was observed that the introduction of the stress hormone cortisol resulted in a decreased immune cell infiltration into the spheroids. Moreover, the presence of cortisol deregulated the normal levels of the pro- and anti-inflammatory cytokines IFN-γand IL-10. We present an individual-based model to explore the interaction dynamics between tumour and immune cells under psychological stress conditions. With our model, we explore the processes underlying the emergence of different levels of immune infiltration, with particular focus on the biological mechanisms regulated by IFN-γand IL-10. The set-up of numerical simulations is defined to mimic the scenarios considered in the experimental study. Similarly to the experimental quantitative analysis, we compute a score that quantifies the level of immune cell infiltration into the tumour. The results of numerical simulations indicate that the motility of immune cells, their capability to infiltrate through tumour cells, their growth rate and the interplay between these cell parameters can affect the level of immune cell infiltration in different ways. Ultimately, numerical simulations of this model support a deeper understanding of the impact of biological stress-induced mechanisms on immune infiltration.
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Interleucina-10 , Neoplasias , Humanos , Hidrocortisona , Neoplasias/patologia , Fenômenos Biofísicos , Estresse Psicológico , Esferoides CelularesRESUMO
The spread of fungi resistant to conventional drugs has become a threatening problem. In this context, antimicrobial peptides (AMPs) have been considered as one of the main alternatives for controlling fungal infections. Here, we report the antifungal and antibiofilm activity and some clues about peptide RQ18's mechanism of action against Candida and Cryptococcus. This peptide inhibited yeast growth from 2.5 µM and killed all Candida tropicalis cells within 2 h incubation. Moreover, it showed a synergistic effect with antifungal agent the amphotericin b. RQ18 reduced biofilm formation and promoted C. tropicalis mature biofilms eradication. RQ18's mechanism of action involves fungal cell membrane damage, which was confirmed by the results of RQ18 in the presence of free ergosterol in the medium and fluorescence microscopy by Sytox green. No toxic effects were observed in murine macrophage cell lines and Galleria mellonella larvae, suggesting fungal target selectivity. Therefore, peptide RQ18 represents a promising strategy as a dual antifungal and antibiofilm agent that contributes to infection control without damaging mammalian cells.
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Anfotericina B , Antifúngicos , Animais , Camundongos , Antifúngicos/farmacologia , Anfotericina B/farmacologia , Peptídeos/farmacologia , Candida tropicalis , Biofilmes , Testes de Sensibilidade Microbiana , MamíferosRESUMO
AIMS: Dopamine beta-hydroxylase (DßH) inhibitors, like zamicastat, hold promise for treating pulmonary arterial hypertension. This study aimed to validate the mechanism of action of zamicastat by studying its effect on the overdrive of the sympathetic nervous system (SNS). METHODS: A single-centre, prospective, double-blind, randomized, placebo-controlled, crossover study evaluated the effect of 400 mg zamicastat in 22 healthy male subjects. Cold pressor test (CPT) was performed at screening and each treatment period on Days -1 and 10. Plasma and 24 h-urine levels of dopamine (DA), epinephrine (EPI) and norepinephrine (NE), and plasma DßH activity, were measured. RESULTS: Compared to placebo, zamicastat showed a - 4.62 mmHg decrease in systolic blood pressure during the cold stimulus vs. rest phases on Day 10 of CPT (P = .020). Zamicastat decreased mean arterial pressure response to cold stimulus during CPT (-2.62 mmHg; P = .025). At Day 10, zamicastat significantly increased plasma DA, before CPT (12.63 ng/L; P = .040) and after CPT (19.22 ng/L; P = .001) as well as the estimated plasma EPI change from baseline after CPT (P = .040). Inhibition of plasma DßH activity ranged from 19.8% to 25.0%. At Day 10, significant reductions in 24-h urinary excretion of EPI (P = .002) and NE (P = .001) were observed. Zamicastat Cτ geometric mean ± GSD ranged from 45.86 ± 1.46 ng/mL on Day 3 to 58.64 ± 1.52 ng/mL on Day 10, with moderate inter-individual variability (CV: 32.6%-36.6%). Steady state was already achieved on Day 6. CONCLUSIONS: Our results demonstrated the effect of zamicastat on the overdrive sympathetic response to cold stimulus, confirming its potential as SNS modulator.
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Pressão Sanguínea , Temperatura Baixa , Estudos Cross-Over , Dopamina beta-Hidroxilase , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Masculino , Método Duplo-Cego , Adulto , Adulto Jovem , Frequência Cardíaca/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Dopamina beta-Hidroxilase/antagonistas & inibidores , Estudos Prospectivos , Norepinefrina/sangue , Sistema Nervoso Simpático/efeitos dos fármacos , Dopamina , Epinefrina/sangueRESUMO
Polyglutamine diseases are a group of neurodegenerative disorders caused by an abnormal expansion of CAG repeat tracts in the codifying regions of nine, otherwise unrelated, genes. While the protein products of these genes are suggested to play diverse cellular roles, the pathogenic mutant proteins bearing an expanded polyglutamine sequence share a tendency to self-assemble, aggregate and engage in abnormal molecular interactions. Understanding the shared paths that link polyglutamine protein expansion to the nervous system dysfunction and the degeneration that takes place in these disorders is instrumental to the identification of targets for therapeutic intervention. Among polyglutamine diseases, spinocerebellar ataxias (SCAs) share many common aspects, including the fact that they involve dysfunction of the cerebellum, resulting in ataxia. Our work aimed at exploring a putative new therapeutic target for the two forms of SCA with higher worldwide prevalence, SCA type 2 (SCA2) and type 3 (SCA3), which are caused by expanded forms of ataxin-2 (ATXN2) and ataxin-3 (ATXN3), respectively. The pathophysiology of polyglutamine diseases has been described to involve an inability to properly respond to cell stress. We evaluated the ability of GTPase-activating protein-binding protein 1 (G3BP1), an RNA-binding protein involved in RNA metabolism regulation and stress responses, to counteract SCA2 and SCA3 pathology, using both in vitro and in vivo disease models. Our results indicate that G3BP1 overexpression in cell models leads to a reduction of ATXN2 and ATXN3 aggregation, associated with a decrease in protein expression. This protective effect of G3BP1 against polyglutamine protein aggregation was reinforced by the fact that silencing G3bp1 in the mouse brain increases human expanded ATXN2 and ATXN3 aggregation. Moreover, a decrease of G3BP1 levels was detected in cells derived from patients with SCA2 and SCA3, suggesting that G3BP1 function is compromised in the context of these diseases. In lentiviral mouse models of SCA2 and SCA3, G3BP1 overexpression not only decreased protein aggregation but also contributed to the preservation of neuronal cells. Finally, in an SCA3 transgenic mouse model with a severe ataxic phenotype, G3BP1 lentiviral delivery to the cerebellum led to amelioration of several motor behavioural deficits. Overall, our results indicate that a decrease in G3BP1 levels may be a contributing factor to SCA2 and SCA3 pathophysiology, and that administration of this protein through viral vector-mediated delivery may constitute a putative approach to therapy for these diseases, and possibly other polyglutamine disorders.
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Doença de Machado-Joseph , Ataxias Espinocerebelares , Humanos , Camundongos , Animais , DNA Helicases/metabolismo , Proteínas de Choque Térmico , Agregados Proteicos , Grânulos de Estresse , Proteínas de Ligação a Poli-ADP-Ribose/genética , RNA Helicases/genética , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/genética , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Ataxina-3/genética , Camundongos Transgênicos , Doença de Machado-Joseph/genéticaRESUMO
Transcriptional dysregulation has been described in spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD), an autosomal dominant ataxia caused by a polyglutamine expansion in the ataxin-3 protein. As ataxin-3 is ubiquitously expressed, transcriptional alterations in blood may reflect early changes that start before clinical onset and might serve as peripheral biomarkers in clinical and research settings. Our goal was to describe enriched pathways and report dysregulated genes, which can track disease onset, severity or progression in carriers of the ATXN3 mutation (pre-ataxic subjects and patients). Global dysregulation patterns were identified by RNA sequencing of blood samples from 40 carriers of ATXN3 mutation and 20 controls and further compared with transcriptomic data from post-mortem cerebellum samples of MJD patients and controls. Ten genes-ABCA1, CEP72, PTGDS, SAFB2, SFSWAP, CCDC88C, SH2B1, LTBP4, MEG3 and TSPOAP1-whose expression in blood was altered in the pre-ataxic stage and simultaneously, correlated with ataxia severity in the overt disease stage, were analysed by quantitative real-time PCR in blood samples from an independent set of 170 SCA3/MJD subjects and 57 controls. Pathway enrichment analysis indicated the Gαi signalling and the oestrogen receptor signalling to be similarly affected in blood and cerebellum. SAFB2, SFSWAP and LTBP4 were consistently dysregulated in pre-ataxic subjects compared to controls, displaying a combined discriminatory ability of 79%. In patients, ataxia severity was associated with higher levels of MEG3 and TSPOAP1. We propose expression levels of SAFB2, SFSWAP and LTBP4 as well as MEG3 and TSPOAP1 as stratification markers of SCA3/MJD progression, deserving further validation in longitudinal studies and in independent cohorts.
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Doença de Machado-Joseph , Ataxias Espinocerebelares , Humanos , Doença de Machado-Joseph/genética , Transcriptoma , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/complicações , Ataxina-3/genética , Biomarcadores , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas dos Microfilamentos/genética , Peptídeos e Proteínas de Sinalização Intracelular/genéticaRESUMO
In the central nervous system (CNS), the crosstalk between neural cells is mediated by extracellular mechanisms, including brain-derived extracellular vesicles (bdEVs). To study endogenous communication across the brain and periphery, we explored Cre-mediated DNA recombination to permanently record the functional uptake of bdEVs cargo over time. To elucidate functional cargo transfer within the brain at physiological levels, we promoted the continuous secretion of physiological levels of neural bdEVs containing Cre mRNA from a localized region in the brain by in situ lentiviral transduction of the striatum of Flox-tdTomato Ai9 mice reporter of Cre activity. Our approach efficiently detected in vivo transfer of functional events mediated by physiological levels of endogenous bdEVs throughout the brain. Remarkably, a spatial gradient of persistent tdTomato expression was observed along the whole brain, exhibiting an increment of more than 10-fold over 4 months. Moreover, bdEVs containing Cre mRNA were detected in the bloodstream and extracted from brain tissue to further confirm their functional delivery of Cre mRNA in a novel and highly sensitive Nanoluc reporter system. Overall, we report a sensitive method to track bdEV transfer at physiological levels, which will shed light on the role of bdEVs in neural communication within the brain and beyond.
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Vesículas Extracelulares , Integrases , Camundongos , Animais , Camundongos Transgênicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Integrases/genética , Integrases/metabolismo , Encéfalo/metabolismo , Vesículas Extracelulares/metabolismoRESUMO
Machado-Joseph disease (MJD)/spinocerebellar ataxia type 3 (SCA3) is the most common autosomal dominantly inherited ataxia worldwide. It is caused by an over-repetition of the trinucleotide CAG within the ATXN3 gene, which confers toxic properties to ataxin-3 (ATXN3) species. RNA interference technology has shown promising therapeutic outcomes but still lacks a non-invasive delivery method to the brain. Extracellular vesicles (EVs) emerged as promising delivery vehicles due to their capacity to deliver small nucleic acids, such as microRNAs (miRNAs). miRNAs were found to be enriched into EVs due to specific signal motifs designated as ExoMotifs. In this study, we aimed at investigating whether ExoMotifs would promote the packaging of artificial miRNAs into EVs to be used as non-invasive therapeutic delivery vehicles to treat MJD/SCA3. We found that miRNA-based silencing sequences, associated with ExoMotif GGAG and ribonucleoprotein A2B1 (hnRNPA2B1), retained the capacity to silence mutant ATXN3 (mutATXN3) and were 3-fold enriched into EVs. Bioengineered EVs containing the neuronal targeting peptide RVG on the surface significantly decreased mutATXN3 mRNA in primary cerebellar neurons from MJD YAC 84.2 and in a novel dual-luciferase MJD mouse model upon daily intranasal administration. Altogether, these findings indicate that bioengineered EVs carrying miRNA-based silencing sequences are a promising delivery vehicle for brain therapy.
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Doença de Machado-Joseph , MicroRNAs , Camundongos , Animais , Doença de Machado-Joseph/genética , Doença de Machado-Joseph/terapia , MicroRNAs/genética , Ataxina-3/genética , Interferência de RNA , Peptídeos/genéticaRESUMO
Neurodegenerative diseases are characterized by extensive loss of function or death of brain cells, hampering the life quality of patients. Brain-targeted drug delivery is challenging, with a low success rate this far. Therefore, the application of targeting ligands in drug vehicles, such as lipid-based and polymeric nanoparticles, holds the promise to overcome the blood-brain barrier (BBB) and direct therapies to the brain, in addition to protect their cargo from degradation and metabolization. In this review, we discuss the barriers to brain delivery and the different types of brain-targeting ligands currently in use in brain-targeted nanoparticles, such as peptides, proteins, aptamers, small molecules, and antibodies. Moreover, we present a detailed review of the different targeting ligands used to direct nanoparticles to specific brain cells, like neurons (C4-3 aptamer, neurotensin, Tet-1, RVG, and IKRG peptides), astrocytes (Aquaporin-4, D4, and Bradykinin B2 antibodies), oligodendrocytes (NG-2 antibody and the biotinylated DNA aptamer conjugated to a streptavidin core Myaptavin-3064), microglia (CD11b antibody), neural stem cells (QTRFLLH, VPTQSSG, and NFL-TBS.40-63 peptides), and to endothelial cells of the BBB (transferrin and insulin proteins, and choline). Reports demonstrated enhanced brain-targeted delivery with improved transport to the specific cell type targeted with the conjugation of these ligands to nanoparticles. Hence, this strategy allows the implementation of high-precision medicine, with reduced side effects or unwanted therapy clearance from the body. Nevertheless, the accumulation of some of these nanoparticles in peripheral organs has been reported indicating that there are still factors to be improved to achieve higher levels of brain targeting. This review is a collection of studies exploring targeting ligands for the delivery of nanoparticles to the brain and we highlight the advantages and limitations of this type of approach in precision therapies.
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Barreira Hematoencefálica , Encéfalo , Sistemas de Liberação de Medicamentos , Nanopartículas , Humanos , Barreira Hematoencefálica/metabolismo , Animais , Encéfalo/metabolismo , Ligantes , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Peptídeos/químicaRESUMO
A 63-year-old woman presented at our emergency department with a disseminated dermatosis that developed after undergoing a cardiac catheterization procedure. Her past medical history included an end-stage renal disease undergoing hemodialysis. Clinical examination revealed erosions and hemorrhagic crusts located on her lips and along the arteriovenous fistula. Additionally, we observed five hyperpigmented macules on her left hand's dorsum and palm and multiple hypopigmented macules in the genital area. Upon medical record review, we discovered the occurrence of prior bullous eruptions following contrast administration. A fixed drug eruption (FDE) due to radiocontrast was diagnosed based on clinical history, clinical examination, eruption timeframe, and positive drug provocation test. Intravenous contrast media reactions can be immediate or delayed, with delayed hypersensitivity reactions (DHR) occurring one hour to seven days post-administration. DHRs often present as maculopapular rashes. FDEs are rare. Skin tests are used to identify culprit agents. Ideally, intradermal tests, with delayed readings, and patch tests are combined for optimal sensitivity. Despite lacking standardized protocols, premedication with corticosteroids may mitigate reaction severity.
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Phosphorylation plays a key role in Alzheimer's disease (AD) pathogenesis, impacting distinct processes such as amyloid-beta (Aß) peptide production and tau phosphorylation. Impaired phosphorylation events contribute to senile plaques and neurofibrillary tangles' formation, two major histopathological hallmarks of AD. Blood-derived extracellular particles (bdEP) can represent a disease-related source of phosphobiomarker candidates, and hence, in this pilot study, bdEP of Control and AD cases were analyzed by a targeted phosphoproteomics approach using a high-density microarray that featured at least 1145 pan-specific and 913 phosphosite-specific antibodies. This approach, innovatively applied to bdEP, allowed the identification of 150 proteins whose expression levels and/or phosphorylation patterns were significantly altered across AD cases. Gene Ontology enrichment and Reactome pathway analysis unraveled potentially relevant molecular targets and disease-associated pathways, and protein-protein interaction networks were constructed to highlight key targets. The discriminatory value of both the total proteome and the phosphoproteome was evaluated by univariate and multivariate approaches. This pilot experiment supports that bdEP are enriched in phosphotargets relevant in an AD context, holding value as peripheral biomarker candidates for disease diagnosis.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Proteoma , Projetos Piloto , Peptídeos beta-Amiloides/metabolismo , Biomarcadores , Emaranhados Neurofibrilares/metabolismoRESUMO
Among the many lysosomal storage disorders (LSDs) that would benefit from the establishment of novel cell models, either patient-derived or genetically engineered, is mucopolysaccharidosis type II (MPS II). Here, we present our results on the establishment and characterization of two MPS II patient-derived stem cell line(s) from deciduous baby teeth. To the best of our knowledge, this is the first time a stem cell population has been isolated from LSD patient samples obtained from the dental pulp. Taking into account our results on the molecular and biochemical characterization of those cells and the fact that they exhibit visible and measurable disease phenotypes, we consider these cells may qualify as a valuable disease model, which may be useful for both pathophysiological assessments and in vitro screenings. Ultimately, we believe that patient-derived dental pulp stem cells (DPSCs), particularly those isolated from human exfoliated deciduous teeth (SHEDs), may represent a feasible alternative to induced pluripotent stem cells (iPSCs) in many labs with standard cell culture conditions and limited (human and economic) resources.
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Doenças por Armazenamento dos Lisossomos , Mucopolissacaridose II , Humanos , Células-Tronco , Linhagem Celular , Dente Decíduo , Lisossomos , Polpa Dentária , Diferenciação Celular/fisiologia , Proliferação de CélulasRESUMO
Nodular hidradenoma is an infrequent benign tumor originating from the proximal portion of the sweat glands, most commonly associated with the apocrine glands. Owing to its variable clinical presentation, correctly diagnosing nodular hidradenoma can be challenging, with several potential conditions in the differential diagnosis to consider. This article presents a healthy 52-year-old woman with an atypical location of nodular hidradenoma, highlighting the critical role of integrating clinical, dermoscopic, and histopathological characteristics for an accurate diagnosis. We discuss the clinical features, dermoscopic findings, histological examination, differential diagnosis, and treatment options for nodular hidradenoma, emphasizing the importance of surgical intervention in preventing potential malignant transformation.
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Acrospiroma , Dermoscopia , Neoplasias das Glândulas Sudoríparas , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias das Glândulas Sudoríparas/patologia , Neoplasias das Glândulas Sudoríparas/diagnóstico , Acrospiroma/patologia , Acrospiroma/diagnóstico , Diagnóstico DiferencialRESUMO
The European Spinocerebellar Ataxia Type 3/Machado-Joseph Disease Initiative (ESMI) is a consortium established with the ambition to set up the largest European longitudinal trial-ready cohort of Spinocerebellar Ataxia Type 3/Machado-Joseph Disease (SCA3/MJD), the most common autosomal dominantly inherited ataxia worldwide. A major focus of ESMI has been the identification of SCA3/MJD biomarkers to enable future interventional studies. As biosample collection and processing variables significantly impact the outcomes of biomarkers studies, biosampling procedures standardisation was done previously to study visit initiation. Here, we describe the ESMI consensus biosampling protocol, developed within the scope of ESMI, that ultimately might be translated to other neurodegenerative disorders, particularly ataxias, being the first step to protocol harmonisation in the field.