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1.
Eur Respir Rev ; 33(171)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296344

RESUMO

INTRODUCTION: Pseudomonas aeruginosa is the most commonly isolated pathogen in bronchiectasis and is associated with worse outcomes. Eradication treatment is recommended by guidelines, but the evidence base is limited. The expected success rate of eradication in clinical practice is not known. METHODS: We conducted a systematic review and meta-analysis according to Meta-Analysis of Observational Studies in Epidemiology guidelines. PubMed, Embase, the Cochrane Database of Systematic Reviews and Clinicaltrials.gov were searched for studies investigating P. aeruginosa eradication treatment using antibiotics (systemic or inhaled) in patients with bronchiectasis. The primary outcome was the percentage of patients negative for P. aeruginosa at 12 months after eradication treatment. Cystic fibrosis was excluded. RESULTS: Six observational studies including 289 patients were included in the meta-analysis. Our meta-analysis found a 12-month P. aeruginosa eradication rate of 40% (95% CI 34-45%; p<0.00001), with no significant heterogeneity (I2=0%). Combined systemic and inhaled antibiotic treatment was associated with a higher eradication rate (48%, 95% CI 41-55%) than systemic antibiotics alone (27%, 13-45%). CONCLUSION: Eradication treatment in bronchiectasis results in eradication of P. aeruginosa from sputum in ∼40% of cases at 12 months. Combined systemic and inhaled antibiotics achieve higher eradication rates than systemic antibiotics alone.


Assuntos
Bronquiectasia , Fibrose Cística , Infecções por Pseudomonas , Adulto , Humanos , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/induzido quimicamente , Administração por Inalação , Antibacterianos/efeitos adversos , Bronquiectasia/diagnóstico , Bronquiectasia/tratamento farmacológico , Fibrose Cística/complicações , Fibrose Cística/diagnóstico , Fibrose Cística/tratamento farmacológico , Pseudomonas aeruginosa
2.
J Appl Lab Med ; 9(1): 4-13, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37647590

RESUMO

BACKGROUND: The -13910 C/T single nucleotide polymorphism located within the MCM6 gene, an enhancer region located upstream of the lactase-phlorizin hydrolase gene, is associated with lactase persistence/non-persistence traits among the Caucasian population. The performance of a new point-of-care CE-IVD (In Vitro Diagnostic) marked isothermal lab-on-phone lactose intolerance assay, using crude samples, was assessed in comparison with Sanger sequencing using purified DNA, as reference method. METHODS: The study was conducted following a non-probability sampling using direct buccal swab (n = 63) and capillary blood (n = 43) clinical samples from a total of 63 volunteers. A 3 × 3 confusion matrix/contingency table was used to evaluate the performance of the isothermal lab-on-phone lactose intolerance assay. RESULTS: The isothermal lab-on-phone lactose intolerance assay successfully detected the -13910 C/T variant with a limit of detection of 5 cells/assay and demonstrated an overall accuracy of 98.41% (95% CI, 91.47%-99.96%) for buccal swab samples and 100% (95% CI, 91.19%-100%) for capillary blood, taking just 90 min from sample to result, with only 2 min hands-on. CONCLUSIONS: The lab-on-phone pocket-sized assay displayed good performance when using direct buccal swab and capillary blood samples, enabling a low-cost, real-time, and accurate genotyping of the -13910 C/T region for the rapid diagnosis of primary lactose intolerance at point-of-care, which enables a prompt implementation of appropriate diet habits and/or intolerance therapies. To our knowledge, this is the first point-of-care genetic test for lactose intolerance to be made available on the market.


Assuntos
Intolerância à Lactose , Humanos , Intolerância à Lactose/diagnóstico , Intolerância à Lactose/genética , Intolerância à Lactose/epidemiologia , Lactase/genética , Sistemas Automatizados de Assistência Junto ao Leito , Genótipo , Testes Imediatos
3.
Mol Ther Nucleic Acids ; 33: 511-528, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37602275

RESUMO

Extracellular vesicles (EVs) have been implicated in the regulation of myogenic differentiation. C2C12 murine myoblast differentiation was reduced following treatment with GW4869 or heparin (to inhibit exosome biogenesis and EV uptake, respectively). Conversely, treatment with C2C12 myotube-conditioned medium enhanced myogenic differentiation. Ultrafiltration-size exclusion liquid chromatography (UF-SEC) was used to isolate EVs and non-EV extracellular protein in parallel from C2C12 myoblast- and myotube-conditioned medium. UF-SEC-purified EVs promoted myogenic differentiation at low doses (≤2 × 108 particles/mL) and were inhibitory at the highest dose tested (2 × 1011 particles/mL). Conversely, extracellular protein fractions had no effect on myogenic differentiation. While the transfer of muscle-enriched miRNAs (myomiRs) has been proposed to mediate the pro-myogenic effects of EVs, we observed that they are scarce in EVs (e.g., 1 copy of miR-133a-3p per 195 EVs). Furthermore, we observed pro-myogenic effects with undifferentiated myoblast-derived EVs, in which myomiR concentrations are even lower, suggestive of a myomiR-independent mechanism underlying the observed pro-myogenic effects. During these investigations we identified technical factors with profound confounding effects on myogenic differentiation. Specifically, co-purification of insulin (a component of Opti-MEM) in non-EV LC fractions and polymer precipitated EV preparations. These findings provide further evidence that polymer-based precipitation techniques should be avoided in EV research.

4.
Ciênc. Saúde Colet. (Impr.) ; 28(6): 1863-1872, jun. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1439855

RESUMO

Abstract Professional drivers show a higher prevalence of obstructive sleep apnea (OSA) compared with the general population. OSA has been widely associated with an increased risk of traffic accidents. This article aims to investigate the presence of risk factors for OSA, its prevalence and the value of screening tools in a truck drivers' cohort. Descriptive and analytical prospective study. Demographic, anthropometric, Epworth Sleepiness Scale, STOP-Bang and Berlin Questionnaire were used to select subjects with suspicion of OSA. Polysomnography (PSG) was performed in individuals with positive screening. Mean age was 44.6±7 years, mean body mass index was 28.7±4 kg/m². Of the 281 truck drivers screened, 88 were positive for potential OSA. Of these, 63 completed PSG study and the diagnosis was confirmed in 85.7% (prevalence of 19.2%). The following variables showed a positive correlation with the apnea-hypopnea index: neck circumference and STOP-Bang. The combination of a predominantly male population, obesity, age distribution and lifestyle could account for the high prevalence of OSA in this specific population. Questionnaires proved to be a valuable screening tool. Screening, treatment, and management of OSA should be a priority as a public safety policy.


Resumo A prevalência de Síndrome de Apneia Obstrutiva do Sono (SAOS) em motoristas profissionais é superior à da população geral e esta tem sido amplamente associada ao risco aumentado de acidentes rodoviários. Este artigo tem por objetivos investigar fatores de risco de SAOS, estimar a sua prevalência e o valor de instrumentos de rastreio numa amostra de motoristas de pesados. Estudo prospetivo descritivo e analítico. Rastreio realizado com recurso a dados demográficos, antropométricos, Escala de Sonolência de Epworth, STOP-Bang e Questionário de Berlim. Nos indivíduos com rastreio positivo foi realizada polissonografia (PSG). A idade média era de 44,6±7 anos, índice de massa corporal 28,7±4 kg/m². Dos 281 motoristas incluídos, 88 apresentavam risco elevado de SAOS. Destes, 63 realizaram PSG, com confirmação diagnóstica em 85,7% (prevalência de 19,2%). O perímetro cervical e STOP-Bang apresentaram correlação positiva com o índice de apneia-hipopneia. A combinação de género predominantemente masculino, obesidade, distribuição de idade e estilo de vida pode justificar a elevada prevalência de SAOS nesta população. O uso de questionários é uma medida eficaz de rastreio. Nos motoristas, o rastreio e tratamento de SAOS deveria ser uma medida de saúde pública prioritária.

5.
Cien Saude Colet ; 28(6): 1863-1872, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37255162

RESUMO

Professional drivers show a higher prevalence of obstructive sleep apnea (OSA) compared with the general population. OSA has been widely associated with an increased risk of traffic accidents. This article aims to investigate the presence of risk factors for OSA, its prevalence and the value of screening tools in a truck drivers' cohort. Descriptive and analytical prospective study. Demographic, anthropometric, Epworth Sleepiness Scale, STOP-Bang and Berlin Questionnaire were used to select subjects with suspicion of OSA. Polysomnography (PSG) was performed in individuals with positive screening. Mean age was 44.6±7 years, mean body mass index was 28.7±4 kg/m². Of the 281 truck drivers screened, 88 were positive for potential OSA. Of these, 63 completed PSG study and the diagnosis was confirmed in 85.7% (prevalence of 19.2%). The following variables showed a positive correlation with the apnea-hypopnea index: neck circumference and STOP-Bang. The combination of a predominantly male population, obesity, age distribution and lifestyle could account for the high prevalence of OSA in this specific population. Questionnaires proved to be a valuable screening tool. Screening, treatment, and management of OSA should be a priority as a public safety policy.


Assuntos
Acidentes de Trânsito , Programas de Rastreamento , Apneia Obstrutiva do Sono , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Programas de Rastreamento/métodos , Veículos Automotores , Estudos Prospectivos , Fatores de Risco , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Inquéritos e Questionários , Prevalência
6.
Int J Biol Macromol ; 239: 124363, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031790

RESUMO

Strategies which are used to address the low levels of intracellular hydrogen peroxide and the development of biocompatible catalysts still need to be fulfilled in tumor chemodynamic therapy. Therefore, a novel tumor-targeted glycogen-based nanoparticle system (GN/He/GOx/HA) was developed to co-deliver hemin (He) and GOx, which can self-supply glucose formed upon degradation of glycogen by α-glycosidase in the lysosome environment, in order to achieve synergistic antitumor therapy. Hyaluronic acid (HA) was selected as the outer shell to protect the activity of GOx, and to increase the uptake by tumor cells via CD44 receptor-mediated endocytosis. GN/He/GOx/HA NPs had a good stability in the blood circulation, but fast release of the therapeutic cargos upon intracellular uptake. Hemin had a cascade catalytic reaction with GOx. Furthermore, GN/He/GOx/HA NPs had the strongest cytotoxicity in Hela cells in a glucose concentration dependent manner. The NPs could efficiently produce reactive oxygen species in tumor cells, resulting in a decrease in the mitochondrial membrane potential and apoptosis of tumor cells. The in vivo results showed that the drug-loaded nanoparticles had good safety, biocompatibility, and efficacious antitumor effect. Therefore, the glycogen-based nanoparticle delivery system provides potential application for self-enhancing CDT, which can be used for effective antitumor therapy.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Humanos , Antineoplásicos/farmacologia , Células HeLa , Glucose Oxidase/metabolismo , Hemina , Glicogênio , Neoplasias/metabolismo , Glucose , Peróxido de Hidrogênio/metabolismo , Linhagem Celular Tumoral
7.
J Control Release ; 354: 635-650, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36634710

RESUMO

Mesenchymal stem cell-derived exosomes (MSC-Exos) have attracted much attention as a potential cell-free therapy for ulcerative colitis (UC), mainly due to their anti-inflammatory, tissue repair, and immunomodulatory properties. Although intravenous injection of MSC-Exos is able to improve UC to a certain extent, oral administration of exosomes is the preferred method to treat gastrointestinal diseases such as UC. However, exosomes contain proteins and nucleic acids that are vulnerable to degradation by the gastrointestinal environment, making oral administration difficult to implement. Layer-by-layer (LbL) self-assembly technology provides a promising strategy for the oral delivery of exosomes. Therefore, an efficient LbL-Exos self-assembly system was constructed in this study for the oral delivery of exosomes targeted to the colon to improve UC treatment. Biocompatible and biodegradable N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) and oxidized konjac glucomannan (OKGM) polysaccharides were used as the outer layers to provide colon targeting and to protect exosomes from degradation. Similar to plain exosomes, LbL-Exos had a similar structure and features, but LbL provided controlled release of exosomes in the inflammatory colon. Compared with intravenous administration, oral administration of LbL-Exos could effectively alleviate UC using half the number of exosomes. Mechanistic studies showed that LbL-Exos were internalized by macrophages and intestinal epithelial cells to exert anti-inflammatory and tissue repair effects and therefore alleviate UC. Furthermore, the LbL-Exos system was able to improve UC via MAPK/NF-κB signaling pathway inhibition. Overall, our data show that LbL-MSC-Exos can alleviate UC after oral administration and therefore may constitute a new strategy for UC treatment in the future.


Assuntos
Colite Ulcerativa , Exossomos , Humanos , Exossomos/metabolismo , Transdução de Sinais , NF-kappa B/metabolismo , Cicatrização
8.
Chem Biol Interact ; 370: 110313, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36566914

RESUMO

Guttiferones belong to the polyisoprenylated benzophenone, a class of compounds, a very restricted group of natural plant products, especially in the Clusiaceae family. They are commonly found in bark, stem, leaves, and fruits of plants of the genus Garcinia and Symphonia. Guttiferones have the following classifications according to their chemical structure: A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, and T. All of them have received growing attention due to its multiple biological activities. This review provides a first comprehensive approach to plant sources, phytochemical profile, specific pharmacological effects, and mechanisms of guttiferones already described. Studies indicate a broad spectrum of pharmacological activities, such as: anti-inflammatory, immunomodulatory, antioxidant, antitumor, antiparasitic, antiviral, and antimicrobial. Despite the low toxicity of these compounds in healthy cells, there is a lack of studies in the literature related to toxicity in general. Given their beneficial effects, guttiferones are expected to be great potential drug candidates for treating cancer and infectious and transmissible diseases. However, further studies are needed to elucidate their toxicity, specific molecular mechanisms and targets, and to perform more in-depth pharmacokinetic studies. This review highlights chemical properties, biological characteristics, and mechanisms of action so far, offering a broad view of the subject and perspectives for the future of guttiferones in therapeutics.


Assuntos
Clusiaceae , Clusiaceae/química , Extratos Vegetais/farmacologia , Compostos Fitoquímicos/farmacologia
9.
Acta Biomater ; 158: 734-746, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563772

RESUMO

Methods capable of distributing antitumour therapeutics uniformly throughout an entire tumour and that can suppress metastasis at the same time, would be of great significance in improving cancer treatment. Bacteria-mediated synergistic therapies have been explored for better specificity, temporal and spatial controllability, as well for providing regulation of the immune microenvironment, in order to provide improved cancer treatment. To achieve this goal, here we developed an engineered bacteria delivery system (GDOX@HSEc) using synthetic biology and interfacial chemistry technologies. The engineered bacteria were concurrently modified to express heparin sulfatase 1 (HSulf-1) inside (HSEc), to attach doxorubicin-loaded glycogen nanoparticles (GDOX NPs) on their surface. Here we demonstrate that HSEc can actively target and colonise tumour sites resulting in HSulf-1 overexpression, thereby suppressing angiogenesis and metastasis. Simultaneously, the GDOX NPs were able to penetrate into tumour cells, leading to intracellular DNA damage. Our results confirmed that a combination of biotherapy and chemotherapy using GDOX@HSEc resulted in significant melanoma suppression in murine models, with reduced side effects. This study provides a powerful platform for the simultaneous delivery of biomacromolecules and chemotherapeutic drugs to tumours, representing an innovative strategy potentially more effective in treating solid tumours. STATEMENT OF SIGNIFICANCE: An original engineered bacteria-based system (GDOX@HSEc) was developed using synthetic biology and interfacial chemistry technologies to concurrently produce naturally occurring heparin sulfatase 1 (HSulf-1) inside and anchor doxorubicin-loaded glycogen nanoparticles on the surface. GDOX@HSEc allowed for combined local delivery of chemotherapeutic agents along with the enzymes and immunostimulatory bacterial adjuvants, which resulted in a synergistic action in the inhibition of tumour growth and metastasis. The study provides a potential therapeutic approach that allows therapeutic agents to be distributed in a spatiotemporally controllable manner in tumours for combinatorial enhanced therapy.


Assuntos
Melanoma , Nanopartículas , Animais , Camundongos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Melanoma/tratamento farmacológico , Nanopartículas/química , Sulfatases/uso terapêutico , Microambiente Tumoral
10.
Antioxidants (Basel) ; 11(11)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36358560

RESUMO

Skin wound healing is a complex process that requires the mutual work of cellular and molecular agents to promote tissue restoration. In order to improve such a process, especially in cases of impaired healing (e.g., diabetic ulcer, chronic wounds), there is a search for substances with healing properties and low toxicity: two features that some natural products-such as the bee product named propolis-exhibit. Propolis is a resinous substance obtained from plant resins and exudates with antioxidant, anti-inflammatory, and antitumoral activities, among other biological ones. Based on the previously reported healing actions of different types of propolis, the Brazilian red propolis (BRP) was tested for this matter. A skin wound excision model in male Wistar rats was performed using two topical formulations with 1% red propolis as treatments: hydroalcoholic extract and Paste. Macroscopical, histological and immunohistochemical analysis were performed, revealing that red propolis enhanced wound contraction, epithelialization, reduced crust formation, and modulated the distribution of healing associated factors, mainly collagen I, collagen III, MMP-9, TGF-ß3 and VEGF. Biochemical analysis with the antioxidants SOD, MPO, GSH and GR showed that propolis acts similarly to the positive control, collagenase, increasing these molecules' activity. These results suggest that BRP promotes enhanced wound healing by modulating growth factors and antioxidant molecules related to cutaneous wound healing.

11.
ESCAPE ; 51: 1081-1086, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36790943

RESUMO

We report progress of an ongoing work to develop a virtual sensor for flowability, which is a critical tool for enabling real time process monitoring in a granulation line. The sensor is based on camera imaging to measure the size and shape distribution of granules produced by wet granulation. Then, statistical methods were used to correlate them with flowability measurements such as ring shear tests, drained angle of repose, dynamic angle of repose, and tapped density. The virtual sensor addresses the issue with these flowability measurements, which are based on off-line characterization methods that can take hours to perform. With a virtual sensor based on real-time measurement methods, the prediction of granule flowability become faster, allowing for timely decisions regarding process control and the supply chain.

12.
Methods Mol Biol ; 2383: 119-141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34766286

RESUMO

Extracellular vesicles are lipid-bilayer-enclosed nanoparticles present in the majority of biological fluids that mediate intercellular communication. EVs are able to transfer their contents (including nucleic acids, proteins, lipids, and small molecules) to recipient cells, and thus hold great promise as drug delivery vehicles. However, their therapeutic application is limited by lack of efficient cargo loading strategies, a need to improve EV tissue-targeting capabilities and a requirement to improve escape from the endolysosomal system. These challenges can be effectively addressed by modifying EVs with peptides which confer specific advantageous properties, thus enhancing their therapeutic potential. Here we provide an overview of the applications of peptide technology with respect to EV therapeutics. We focus on the utility of EV-modifying peptides for the purposes of promoting cargo loading, tissue-targeting and endosomal escape, leading to enhanced delivery of the EV cargo to desired cells/tissues and subcellular target locations. Both endogenous and exogenous methods for modifying EVs with peptides are considered.


Assuntos
Vesículas Extracelulares , Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos , Tecnologia
14.
Nat Commun ; 12(1): 6666, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795295

RESUMO

Extracellular vesicles (EVs) are biological nanoparticles with important roles in intercellular communication, and potential as drug delivery vehicles. Here we demonstrate a role for the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in EV assembly and secretion. We observe high levels of GAPDH binding to the outer surface of EVs via a phosphatidylserine binding motif (G58), which promotes extensive EV clustering. Further studies in a Drosophila EV biogenesis model reveal that GAPDH is required for the normal generation of intraluminal vesicles in endosomal compartments, and promotes vesicle clustering. Fusion of the GAPDH-derived G58 peptide to dsRNA-binding motifs enables highly efficient loading of small interfering RNA (siRNA) onto the EV surface. Such vesicles efficiently deliver siRNA to multiple anatomical regions of the brain in a Huntington's disease mouse model after systemic injection, resulting in silencing of the huntingtin gene in different regions of the brain.


Assuntos
Encéfalo/metabolismo , Vesículas Extracelulares/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Células-Tronco Mesenquimais/metabolismo , RNA Interferente Pequeno/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares/ultraestrutura , Gliceraldeído-3-Fosfato Desidrogenases/genética , Células HEK293 , Células HeLa , Humanos , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/genética , Doença de Huntington/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos C57BL , Fosfatidilserinas/metabolismo , Ligação Proteica , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética
15.
Nat Biomed Eng ; 5(9): 1084-1098, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34616047

RESUMO

Extracellular vesicles (EVs) can be functionalized to display specific protein receptors on their surface. However, surface-display technology typically labels only a small fraction of the EV population. Here, we show that the joint display of two different therapeutically relevant protein receptors on EVs can be optimized by systematically screening EV-loading protein moieties. We used cytokine-binding domains derived from tumour necrosis factor receptor 1 (TNFR1) and interleukin-6 signal transducer (IL-6ST), which can act as decoy receptors for the pro-inflammatory cytokines tumour necrosis factor alpha (TNF-α) and IL-6, respectively. We found that the genetic engineering of EV-producing cells to express oligomerized exosomal sorting domains and the N-terminal fragment of syntenin (a cytosolic adaptor of the single transmembrane domain protein syndecan) increased the display efficiency and inhibitory activity of TNFR1 and IL-6ST and facilitated their joint display on EVs. In mouse models of systemic inflammation, neuroinflammation and intestinal inflammation, EVs displaying the cytokine decoys ameliorated the disease phenotypes with higher efficacy as compared with clinically approved biopharmaceutical agents targeting the TNF-α and IL-6 pathways.


Assuntos
Vesículas Extracelulares , Doenças Neuroinflamatórias , Animais , Citocinas , Inflamação , Camundongos , Fator de Necrose Tumoral alfa
16.
Sci Adv ; 7(34)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34417184

RESUMO

Spinal and bulbar muscular atrophy (SBMA) is an X-linked, adult-onset neuromuscular condition caused by an abnormal polyglutamine (polyQ) tract expansion in androgen receptor (AR) protein. SBMA is a disease with high unmet clinical need. Recent studies have shown that mutant AR-altered transcriptional activity is key to disease pathogenesis. Restoring the transcriptional dysregulation without affecting other AR critical functions holds great promise for the treatment of SBMA and other AR-related conditions; however, how this targeted approach can be achieved and translated into a clinical application remains to be understood. Here, we characterized the role of AR isoform 2, a naturally occurring variant encoding a truncated AR lacking the polyQ-harboring domain, as a regulatory switch of AR genomic functions in androgen-responsive tissues. Delivery of this isoform using a recombinant adeno-associated virus vector type 9 resulted in amelioration of the disease phenotype in SBMA mice by restoring polyQ AR-dysregulated transcriptional activity.


Assuntos
Atrofia Bulboespinal Ligada ao X , Receptores Androgênicos , Animais , Atrofia Bulboespinal Ligada ao X/genética , Atrofia Bulboespinal Ligada ao X/terapia , Terapia Genética , Camundongos , Fenótipo , Isoformas de Proteínas/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
17.
Eur J Case Rep Intern Med ; 8(7): 002744, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377706

RESUMO

Mediastinal tumours can be incidental findings on chest x-ray or present with systemic symptoms and/or direct effect of the mediastinal mass. We report the case of a woman with symptomatic thymoma B1 and simultaneous thymus tuberculosis. LEARNING POINTS: The association of tuberculosis (TB) of the thymus and thymoma is extremely rare.The differential diagnosis of a mediastinal mass should include TB, particularly in endemic regions.Mediastinal mass resection or biopsy can be of great value in diagnostic work-up.

18.
Cells ; 10(6)2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207405

RESUMO

The extracellular environment consists of a plethora of molecules, including extracellular miRNA that can be secreted in association with extracellular vesicles (EVs) or soluble protein complexes (non-EVs). Yet, interest in therapeutic short RNA carriers lies mainly in EVs, the vehicles conveying the great majority of the biological activity. Here, by overexpressing miRNA and shRNA sequences in parent cells and using size exclusion liquid chromatography (SEC) to separate the secretome into EV and non-EV fractions, we saw that >98% of overexpressed miRNA was secreted within the non-EV fraction. Furthermore, small RNA sequencing studies of native miRNA transcripts revealed that although the abundance of miRNAs in EVs, non-EVs and parent cells correlated well (R2 = 0.69-0.87), quantitatively an outstanding 96.2-99.9% of total miRNA was secreted in the non-EV fraction. Nevertheless, though EVs contained only a fraction of secreted miRNAs, these molecules were stable at 37 °C in a serum-containing environment, indicating that if sufficient miRNA loading is achieved, EVs can remain delivery-competent for a prolonged period of time. This study suggests that the passive endogenous EV loading strategy might be a relatively wasteful way of loading miRNA to EVs, and active miRNA loading approaches are needed for developing advanced EV miRNA therapies in the future.


Assuntos
Vesículas Extracelulares/genética , Vesículas Extracelulares/fisiologia , RNA Interferente Pequeno/genética , Linhagem Celular , Células HEK293 , Humanos , MicroRNAs/genética , Análise de Sequência de RNA/métodos
20.
Biomaterials ; 266: 120435, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049461

RESUMO

The cytokine interleukin 6 (IL6) is a key mediator of inflammation that contributes to skeletal muscle pathophysiology. IL6 activates target cells by two main mechanisms, the classical and trans-signalling pathways. While classical signalling is associated with the anti-inflammatory activities of the cytokine, the IL6 trans-signalling pathway mediates chronic inflammation and is therefore a target for therapeutic intervention. Extracellular vesicles (EVs) are natural, lipid-bound nanoparticles, with potential as targeted delivery vehicles for therapeutic macromolecules. Here, we engineered EVs to express IL6 signal transducer (IL6ST) decoy receptors to selectively inhibit the IL6 trans-signalling pathway. The potency of the IL6ST decoy receptor EVs was optimized by inclusion of a GCN4 dimerization domain and a peptide sequence derived from syntenin-1 which targets the decoy receptor to EVs. The resulting engineered EVs were able to efficiently inhibit activation of the IL6 trans-signalling pathway in reporter cells, while having no effect on the IL6 classical signalling. IL6ST decoy receptor EVs, were also capable of blocking the IL6 trans-signalling pathway in C2C12 myoblasts and myotubes, thereby inhibiting the phosphorylation of STAT3 and partially reversing the anti-differentiation effects observed when treating cells with IL6/IL6R complexes. Treatment of a Duchenne muscular dystrophy mouse model with IL6ST decoy receptor EVs resulted in a reduction in STAT3 phosphorylation in the quadriceps and gastrocnemius muscles of these mice, thereby demonstrating in vivo activity of the decoy receptor EVs as a potential therapy. Taken together, this study reveals the IL6 trans-signalling pathway as a promising therapeutic target in DMD, and demonstrates the therapeutic potential of IL6ST decoy receptor EVs.


Assuntos
Vesículas Extracelulares , Distrofia Muscular de Duchenne , Animais , Interleucina-6 , Camundongos , Fibras Musculares Esqueléticas , Transdução de Sinais
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