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1.
Gen Comp Endocrinol ; 343: 114369, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611673

RESUMO

In starfish, a relaxin-like gonad-stimulating peptide (RGP) acts as a gonadotropin that triggers gamete maturation and spawning. In common with other relaxin/insulin superfamily peptides, RGP consists of an A- and a B-chain, with cross-linkages mediated by one intra- and two inter-chain disulfide bonds. In this study, a second relaxin-like peptide (RLP2) was identified in starfish species belonging to the orders Valvatida, Paxillosida, and Forcipulatida. Like RGP, RLP2 precursors comprise a signal peptide and a C-peptide in addition to the A- and B-chains. However, a unique cysteine motif [CC-(3X)-C-(10X)-C] is present in the A-chain of RLP2, which contrasts with the cysteine motif in other members of the relaxin/insulin superfamily [CC-(3X)-C-(8X)-C]. Importantly, in vitro pharmacological tests revealed that Patiria pectinifera RLP2 (Ppe-RLP2) and Asterias rubens RLP2 (Aru-RLP2) trigger shedding of mature eggs from ovaries of P. pectinifera and A. rubens, respectively. Furthermore, the potencies of Ppe-RLP2 and Aru-RLP2 as gonadotropic peptides were similar to those of Ppe-RGP and Aru-RGP, respectively, and the effect of RLP2 exhibited partial species-specificity. These findings indicate that two relaxin-type peptides regulate spawning in starfish and therefore we propose that RGP and RLP2 are renamed RGP1 and RGP2, respectively.


Assuntos
Asterias , Asterina , Relaxina , Animais , Estrelas-do-Mar , Cisteína , Peptídeo C , Insulina
2.
Eur J Clin Invest ; 51(3): e13474, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33336385

RESUMO

INTRODUCTION: Despite being widely used as a screening tool, a rigorous scientific evaluation of infrared thermography for the diagnosis of minimally symptomatic patients suspected of having COVID-19 infection has not been performed. METHODS: A consecutive sample of 60 adult individuals with a history of close contact with COVID-19 infected individuals and mild respiratory symptoms for less than 7 days and 20 confirmed COVID-19 negative healthy volunteers were enrolled in the study. Infrared thermograms of the face were obtained with a mobile camera, and RT-PCR was used as the reference standard test to diagnose COVID-19 infection. Temperature values and distribution of the face of healthy volunteers and patients with and without COVID-19 infection were then compared. RESULTS: Thirty-four patients had an RT-PCR confirmed diagnosis of COVID-19 and 26 had negative test results. The temperature asymmetry between the lacrimal caruncles and the forehead was significantly higher in COVID-19 positive individuals. Through a random forest analysis, a cut-off value of 0.55°C was found to discriminate with an 82% accuracy between patients with and without COVID-19 confirmed infection. CONCLUSIONS: Among adults with a history of COVID-19 exposure and mild respiratory symptoms, a temperature asymmetry of ≥ 0.55°C between the lacrimal caruncle and the forehead is highly suggestive of COVID-19 infection. This finding questions the widespread use of the measurement of absolute temperature values of the forehead as a COVID-19 screening tool.


Assuntos
Temperatura Corporal , COVID-19/diagnóstico , Olho , Testa , Termografia/métodos , Adulto , COVID-19/fisiopatologia , Teste de Ácido Nucleico para COVID-19 , Estudos de Casos e Controles , Feminino , Humanos , Raios Infravermelhos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , SARS-CoV-2 , Índice de Gravidade de Doença
3.
Int J Mol Sci ; 21(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340135

RESUMO

The mitogen-activated protein kinase (MAPK)-interacting kinases (MNKs) are involved in oncogenic transformation and can promote metastasis and tumor progression. In human cells, there are four MNKs isoforms (MNK1a/b and MNK2a/b), derived from two genes by alternative splicing. These kinases play an important role controlling the expression of specific proteins involved in cell cycle, cell survival and cell motility via eukaryotic initiation factor 4E (eIF4E) regulation, but also through other substrates such as heterogeneous nuclear ribonucleoprotein A1, polypyrimidine tract-binding protein-associated splicing factor and Sprouty 2. In this review, we provide an overview of the role of MNK in human cancers, describing the studies conducted to date to elucidate the mechanism involved in the action of MNKs, as well as the development of MNK inhibitors in different hematological cancers and solid tumors.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Antineoplásicos/farmacologia , Biomarcadores , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Suscetibilidade a Doenças , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias/mortalidade , Prognóstico , Inibidores de Proteínas Quinases/farmacologia
4.
Mol Ther ; 26(8): 2047-2059, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29910175

RESUMO

Since Toll-like receptor 4 (TLR4) mediates brain damage after stroke, development of TLR4 antagonists is a promising therapeutic strategy for this disease. Our aim was to generate TLR4-blocking DNA aptamers to be used for stroke treatment. From a random oligonucleotide pool, we identified two aptamers (ApTLR#1R, ApTLR#4F) with high affinity for human TLR4 by systematic evolution of ligands by exponential enrichment (SELEX). Optimized truncated forms (ApTLR#1RT, ApTLR#4FT) were obtained. Our data demonstrate specific binding of both aptamers to human TLR4 as well as a TLR4 antagonistic effect. ApTLR#4F and ApTLR#4FT showed a long-lasting protective effect against brain injury induced by middle cerebral artery occlusion (MCAO), an effect that was absent in TLR4-deficient mice. Similar effects were obtained in other MCAO models, including in rat. Additionally, efficacy of ApTLR#4FT in a model of brain ischemia-reperfusion in rat supports the use of this aptamer in patients undergoing artery recanalization induced by pharmacological or mechanical interventions. The absence of major toxicology aspects and the good safety profile of the aptamers further encourage their future clinical positioning for stroke therapy and possibly other diseases in which TLR4 plays a deleterious role.


Assuntos
Aptâmeros de Nucleotídeos/administração & dosagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Receptor 4 Toll-Like/metabolismo , Animais , Aptâmeros de Nucleotídeos/farmacologia , Modelos Animais de Doenças , Humanos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/etiologia , Camundongos , Ratos , Técnica de Seleção de Aptâmeros , Transdução de Sinais , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo
5.
Sensors (Basel) ; 18(5)2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29701721

RESUMO

Fall detection is a very important challenge that affects both elderly people and the carers. Improvements in fall detection would reduce the aid response time. This research focuses on a method for fall detection with a sensor placed on the wrist. Falls are detected using a published threshold-based solution, although a study on threshold tuning has been carried out. The feature extraction is extended in order to balance the dataset for the minority class. Alternative models have been analyzed to reduce the computational constraints so the solution can be embedded in smart-phones or smart wristbands. Several published datasets have been used in the Materials and Methods section. Although these datasets do not include data from real falls of elderly people, a complete comparison study of fall-related datasets shows statistical differences between the simulated falls and real falls from participants suffering from impairment diseases. Given the obtained results, the rule-based systems represent a promising research line as they perform similarly to neural networks, but with a reduced computational cost. Furthermore, support vector machines performed with a high specificity. However, further research to validate the proposal in real on-line scenarios is needed. Furthermore, a slight improvement should be made to reduce the number of false alarms.

6.
Proc Natl Acad Sci U S A ; 109(29): 11872-7, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22753475

RESUMO

We report the genome sequence of melon, an important horticultural crop worldwide. We assembled 375 Mb of the double-haploid line DHL92, representing 83.3% of the estimated melon genome. We predicted 27,427 protein-coding genes, which we analyzed by reconstructing 22,218 phylogenetic trees, allowing mapping of the orthology and paralogy relationships of sequenced plant genomes. We observed the absence of recent whole-genome duplications in the melon lineage since the ancient eudicot triplication, and our data suggest that transposon amplification may in part explain the increased size of the melon genome compared with the close relative cucumber. A low number of nucleotide-binding site-leucine-rich repeat disease resistance genes were annotated, suggesting the existence of specific defense mechanisms in this species. The DHL92 genome was compared with that of its parental lines allowing the quantification of sequence variability in the species. The use of the genome sequence in future investigations will facilitate the understanding of evolution of cucurbits and the improvement of breeding strategies.


Assuntos
Evolução Biológica , Cucumis melo/genética , Genoma de Planta/genética , Filogenia , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos/genética , Elementos de DNA Transponíveis/genética , Resistência à Doença/genética , Genes Duplicados/genética , Genes de Plantas/genética , Genômica/métodos , Funções Verossimilhança , Modelos Genéticos , Anotação de Sequência Molecular , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA
7.
BMC Genomics ; 15: 1131, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25523007

RESUMO

BACKGROUND: Plant NBS-LRR -resistance genes tend to be found in clusters, which have been shown to be hot spots of genome variability. In melon, half of the 81 predicted NBS-LRR genes group in nine clusters, and a 1 Mb region on linkage group V contains the highest density of R-genes and presence/absence gene polymorphisms found in the melon genome. This region is known to contain the locus of Vat, an agronomically important gene that confers resistance to aphids. However, the presence of duplications makes the sequencing and annotation of R-gene clusters difficult, usually resulting in multi-gapped sequences with higher than average errors. RESULTS: A 1-Mb sequence that contains the largest NBS-LRR gene cluster found in melon was improved using a strategy that combines Illumina paired-end mapping and PCR-based gap closing. Unknown sequence was decreased by 70% while about 3,000 SNPs and small indels were corrected. As a result, the annotations of 18 of a total of 23 NBS-LRR genes found in this region were modified, including additional coding sequences, amino acid changes, correction of splicing boundaries, or fussion of ORFs in common transcription units. A phylogeny analysis of the R-genes and their comparison with syntenic sequences in other cucurbits point to a pattern of local gene amplifications since the diversification of cucurbits from other families, and through speciation within the family. A candidate Vat gene is proposed based on the sequence similarity between a reported Vat gene from a Korean melon cultivar and a sequence fragment previously absent in the unrefined sequence. CONCLUSIONS: A sequence refinement strategy allowed substantial improvement of a 1 Mb fragment of the melon genome and the re-annotation of the largest cluster of NBS-LRR gene homologues found in melon. Analysis of the cluster revealed that resistance genes have been produced by sequence duplication in adjacent genome locations since the divergence of cucurbits from other close families, and through the process of speciation within the family a candidate Vat gene was also identified using sequence previously unavailable, which demonstrates the advantages of genome assembly refinements when analyzing complex regions such as those containing clusters of highly similar genes.


Assuntos
Cucurbitaceae/genética , Genes de Plantas/genética , Variação Genética , Família Multigênica/genética , Animais , Afídeos , Cucurbitaceae/fisiologia , Anotação de Sequência Molecular , Doenças das Plantas , Especificidade da Espécie , Sintenia
8.
J Comp Neurol ; 532(1): e25585, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289190

RESUMO

Reproductive processes are regulated by a variety of neuropeptides in vertebrates and invertebrates. In starfish (phylum Echinodermata), relaxin-like gonad-stimulating peptide triggers oocyte maturation and spawning. However, little is known about other neuropeptides as potential regulators of reproduction in starfish. To address this issue, here, we used histology and immunohistochemistry to analyze the reproductive system of the starfish Asterias rubens at four stages of the seasonal reproductive cycle in male and female animals, investigating the expression of eight neuropeptides: the corticotropin-releasing hormone-type neuropeptide ArCRH, the calcitonin-type neuropeptide ArCT, the pedal peptide-type neuropeptides ArPPLN1b and ArPPLN2h, the vasopressin/ocytocin-type neuropeptide asterotocin, the gonadotropin-releasing hormone-type neuropeptide ArGnRH, and the somatostatin/allatostatin-C-type neuropeptides ArSS1 and ArSS2. The expression of five neuropeptides, ArCRH, ArCT, ArPPLN1b, ArPPLN2h, and asterotocin, was detected in the gonoducts and/or gonads. For example, extensive ArPPLN2h expression was revealed in the coelomic epithelial layer of the gonads throughout the seasonal reproductive cycle in both males and females. However, seasonal and/or sexual differences in the patterns of neuropeptide expression were also observed. Informed by these findings, the in vitro pharmacological effects of neuropeptides on gonad preparations from male and female starfish were investigated. This revealed that ArSS1 causes gonadal contraction and that ArPPLN2h causes gonadal relaxation, with both neuropeptides being more effective on ovaries than testes. Collectively, these findings indicate that multiple neuropeptide signaling systems are involved in the regulation of reproductive function in starfish, with some neuropeptides exerting excitatory or inhibitory effects on gonad contractility that may be physiologically relevant when gametes are expelled during spawning.


Assuntos
Asterias , Neuropeptídeos , Feminino , Masculino , Animais , Estrelas-do-Mar , Genitália , Equinodermos
9.
Acad Emerg Med ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38450918

RESUMO

BACKGROUND: Federal regulations allow exception from informed consent (EFIC) to study emergent conditions when obtaining prospective consent is not feasible. Little is known about public views on including children in EFIC studies. The Pediatric Dose Optimization for Seizures in EMS (PediDOSE) trial implements age-based, standardized midazolam dosing for pediatric seizures. The primary objective of this study was to determine public support for and concerns about the PediDOSE EFIC trial. The secondary objective was to assess how support for PediDOSE varied by demographics. METHODS: We conducted a mixed-methods study in 20 U.S. communities. Participants reviewed information about PediDOSE before completing an online survey. Descriptive data were generated. Univariable and multivariable logistic regression analysis identified factors associated with support for PediDOSE. Reviewers identified themes from free-text response data regarding participant concerns. RESULTS: Of 2450 respondents, 79% were parents/guardians, and 20% had a child with previous seizures. A total of 96% of respondents supported PediDOSE being conducted, and 70% approved of children being enrolled without prior consent. Non-Hispanic Black respondents were less likely than non-Hispanic White respondents to support PediDOSE with an adjusted odds ratio (aOR) of 0.57 (95% CI 0.42-0.75). Health care providers were more likely to support PediDOSE, with strongest support among prehospital emergency medicine clinicians (aOR 5.82, 95% CI 3.19-10.62). Age, gender, parental status, and level of education were not associated with support of PediDOSE. Common concerns about PediDOSE included adverse effects, legal and ethical concerns about enrolling without consent, and potential racial bias. CONCLUSIONS: In communities where this study will occur, most respondents supported PediDOSE being conducted with EFIC and most approved of children being enrolled without prior consent. Support was lowest among non-Hispanic Black respondents and highest among health care providers. Further research is needed to determine optimal ways to address the concerns of specific racial and ethnic groups when conducting EFIC trials.

10.
Biochim Biophys Acta ; 1823(2): 430-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22178387

RESUMO

Poor oxygenation (hypoxia) influences important physiological and pathological situations, including development, ischemia, stroke and cancer. Hypoxia induces protein synthesis inhibition that is primarily regulated at the level of initiation step. This regulation generally takes place at two stages, the phosphorylation of the subunit α of the eukaryotic initiation factor (eIF) 2 and the inhibition of the eIF4F complex availability by dephosphorylation of the inhibitory protein 4E-BP1 (eukaryotic initiation factor 4E-binding protein 1). The contribution of each of them is mainly dependent of the extent of the oxygen deprivation. We have evaluated the regulation of hypoxia-induced translation inhibition in nerve growth factor (NGF)-differentiated PC12 cells subjected to a low oxygen concentration (0.1%) at several times. Our findings indicate that protein synthesis inhibition occurs primarily by the disruption of eIF4F complex through 4E-BP1 dephosphorylation, which is produced by the inhibition of the mammalian target of rapamycin (mTOR) activity via the activation of REDD1 (regulated in development and DNA damage 1) protein in a hypoxia-inducible factor 1 (HIF1)-dependent manner, as well as the translocation of eIF4E to the nucleus. In addition, this mechanism is reinforced by the increase in 4E-BP1 levels, mainly at prolonged times of hypoxia.


Assuntos
Hipóxia Celular , Fator de Iniciação 4F em Eucariotos/metabolismo , Fator de Crescimento Neural/farmacologia , Neurônios/metabolismo , Biossíntese de Proteínas , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Transporte/metabolismo , Diferenciação Celular , Fator de Iniciação 4F em Eucariotos/genética , Peptídeos e Proteínas de Sinalização Intracelular , Neurônios/citologia , Células PC12 , Fosfoproteínas/metabolismo , Ratos
11.
BMC Genomics ; 14: 782, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24219589

RESUMO

BACKGROUND: Changes in the copy number of DNA sequences are one of the main mechanisms generating genome variability in eukaryotes. These changes are often related to phenotypic effects such as genetic disorders or novel pathogen resistance. The increasing availability of genome sequences through the application of next-generation massive sequencing technologies has allowed the study of genomic polymorphisms at both the interspecific and intraspecific levels, thus helping to understand how species adapt to changing environments through genome variability. RESULTS: Data on gene presence/absence variation (PAV) in melon was obtained by resequencing a cultivated accession and an old-relative melon variety, and using previously obtained resequencing data from three other melon cultivars, among them DHL92, on which the current draft melon genome sequence is based. A total of 1,697 PAV events were detected, involving 4.4% of the predicted melon gene complement. In all, an average 1.5% of genes were absent from each analyzed cultivar as compared to the DHL92 reference genome. The most populated functional category among the 304 PAV genes of known function was that of stress response proteins (30% of all classified PAVs). Our results suggest that genes from multi-copy families are five times more likely to be affected by PAV than singleton genes. Also, the chance of genes present in the genome in tandem arrays being affected by PAV is double that of isolated genes, with PAV genes tending to be in longer clusters. The highest concentration of PAV events detected in the melon genome was found in a 1.1 Mb region of linkage group V, which also shows the highest density of melon stress-response genes. In particular, this region contains the longest continuous gene-containing PAV sequence so far identified in melon. CONCLUSIONS: The first genome-wide report of PAV variation among several melon cultivars is presented here. Multi-copy and clustered genes, especially those with putative stress-response functions, were found to be particularly affected by PAV polymorphisms. As cucurbits are known to possess a significantly lower number of defense-related genes compared to other plant species, PAV variation may play an important role in generating new pathogen resistances at the subspecies level. In addition, these results show the limitations of single reference genome sequences as the only basis for characterization and cloning of resistance genes.


Assuntos
Cucumis melo/imunologia , Cucurbitaceae/genética , Estresse Fisiológico/genética , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos/genética , Cromossomos de Plantas/genética , Cucumis melo/crescimento & desenvolvimento , Variação Genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala
12.
Methods Mol Biol ; 2570: 235-242, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36156787

RESUMO

Aptamers are single-stranded oligonucleotides able to recognize a target with high affinity and specificity. Aptamers are used in different diagnostics applications, highlighting, among all, variations of the traditional enzyme-linked immunosorbent assay (ELISA). In this chapter, we show the procedures for the development of two types of indirect ELONA: a sandwich ELONA and a direct ELONA coupled to either real-time quantitative PCR as a direct and sensitive readout.


Assuntos
Aptâmeros de Nucleotídeos , Ensaios Enzimáticos , Ensaio de Imunoadsorção Enzimática , Reação em Cadeia da Polimerase em Tempo Real , Técnica de Seleção de Aptâmeros/métodos
13.
J Comp Neurol ; 531(13): 1299-1316, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37212624

RESUMO

Oocyte maturation and gamete release (spawning) in starfish are triggered by relaxin-like gonad-stimulating peptide (RGP), a neuropeptide that was first isolated from the radial nerve cords of these animals. Hitherto, it has generally been assumed that the radial nerve cords are the source of RGP that triggers spawning physiologically. To investigate other sources of RGP, here we report the first comprehensive anatomical analysis of its expression, using both in situ hybridization and immunohistochemistry to map RGP precursor transcripts and RGP, respectively, in the starfish Asterias rubens. Cells expressing RGP precursor transcripts were revealed in the ectoneural epithelium of the radial nerve cords and circumoral nerve ring, arm tips, tube feet, cardiac stomach, pyloric stomach, and, most notably, gonoducts. Using specific antibodies to A. rubens RGP, immunostaining was revealed in cells and/or fibers in the ectoneural region of the radial nerve cords and circumoral nerve ring, tube feet, terminal tentacle and other arm tip-associated structures, body wall, peristomial membrane, esophagus, cardiac stomach, pyloric stomach, pyloric caeca, and gonoducts. Our discovery that RGP is expressed in the gonoducts of A. rubens proximal to its gonadotropic site of action in the gonads is important because it provides a new perspective on how RGP may act as a gonadotropin in starfish. Thus, we hypothesize that it is the release of RGP from the gonoducts that triggers gamete maturation and spawning in starfish, while RGP produced in other parts of the body may regulate other physiological/behavioral processes.


Assuntos
Asterias , Neuropeptídeos , Relaxina , Animais , Estrelas-do-Mar/metabolismo , Relaxina/química , Relaxina/metabolismo , Gônadas/metabolismo , Asterias/metabolismo , Neuropeptídeos/metabolismo
14.
Pathogens ; 12(7)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37513786

RESUMO

In 2020, the WHO established the road map for neglected tropical diseases 2021-2030, which aims to control and eradicate 20 diseases, including leishmaniosis and Chagas disease. In addition, since 2015, the WHO has been developing a Global Action Plan on Antimicrobial Resistance. In this context, the achievement of innovative strategies as an alternative to replace conventional therapies is a first-order socio-sanitary priority, especially regarding endemic zoonoses in poor regions, such as those caused by Trypanosoma cruzi and Leishmania spp. infections. In this scenario, it is worth highlighting a group of natural peptide molecules (AMPs and CPPs) that are promising strategies for improving therapeutic efficacy against these neglected zoonoses, as they avoid the development of toxicity and resistance of conventional treatments. This review presents the novelties of these peptide molecules and their ability to cross a whole system of cell membranes as well as stimulate host immune defenses or even serve as vectors of molecules. The efforts of the biotechnological sector will make it possible to overcome the limitations of antimicrobial peptides through encapsulation and functionalization methods to obtain approval for these treatments to be used in clinical programs for the eradication of leishmaniosis and Chagas disease.

15.
Nanoscale ; 15(47): 19110-19127, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37990926

RESUMO

Breast cancer is a complex and heterogeneous disease with a high mortality rate due to non-specific cytotoxicity, low intratumoral accumulation and drug resistance associated with the ineffectiveness of chemotherapy. In recent years, all efforts have been focused on finding new markers and therapeutic targets, protein kinase MNK1b being a promising candidate. Recently, an aptamer known as apMNK2F showed a highly specific interaction with this protein kinase, leading to a significant reduction in tumour cell proliferation, migration and colony formation. However, as aptamers are unable to penetrate the cell membrane and reach the target, these small biomolecules need to be conjugated to suitable vectors that can transport and protect them inside the cells. In this work, covalent conjugation between biocompatible and non-harmful nanoemulsions of vitamin E and sphingomyelin and the aptamer was performed to facilitate intracellular delivery of the therapeutic aptamer apMNK2F. All strategies employed were based on 2-step bioconjugation and optimized to get the simplest and most reproducible vehicle with the highest association efficiency (about 70% in all cases). The ability of the nanosystems to successfully deliver the conjugated therapeutic aptamer was demonstrated and compared to other commercial transfection agents such as Lipofectamine 2000, leading to an effective decrease of breast cancer cell proliferation in the MDA-MB-231 cell line. The proliferation inhibition of the aptamer nanoconjugates compared to the non-conjugated aptamer provides evidence that the antitumoral capacity derived from kinase interaction is improved in a dose-dependent manner. Furthermore, various experiments including cell migration and colony formation assays, along with apoptosis induction experiments, emphasize the significant antitumoral potential. Overall, the obtained results indicate that the developed formulation could be a promising therapy for the treatment of breast cancer.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias da Mama , Neoplasias Mamárias Animais , Animais , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Esfingomielinas , Aptâmeros de Nucleotídeos/química , Proliferação de Células , Proteínas Quinases , Linhagem Celular Tumoral
16.
Pharmaceutics ; 15(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37111758

RESUMO

Lung cancer is the leading cause of cancer-related death worldwide. Its late diagnosis and consequently poor survival make necessary the search for new therapeutic targets. The mitogen-activated protein kinase (MAPK)-interacting kinase 1 (MNK1) is overexpressed in lung cancer and correlates with poor overall survival in non-small cell lung cancer (NSCLC) patients. The previously identified and optimized aptamer from our laboratory against MNK1, apMNKQ2, showed promising results as an antitumor drug in breast cancer in vitro and in vivo. Thus, the present study shows the antitumor potential of apMNKQ2 in another type of cancer where MNK1 plays a significant role, such as NSCLC. The effect of apMNKQ2 in lung cancer was studied with viability, toxicity, clonogenic, migration, invasion, and in vivo efficacy assays. Our results show that apMNKQ2 arrests the cell cycle and reduces viability, colony formation, migration, invasion, and epithelial-mesenchymal transition (EMT) processes in NSCLC cells. In addition, apMNKQ2 reduces tumor growth in an A549-cell line NSCLC xenograft model. In summary, targeting MNK1 with a specific aptamer may provide an innovative strategy for lung cancer treatment.

17.
JAMA Neurol ; 80(8): 779-788, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37338893

RESUMO

Importance: ApTOLL is a TLR4 antagonist with proven preclinical neuroprotective effect and a safe profile in healthy volunteers. Objective: To assess the safety and efficacy of ApTOLL in combination with endovascular treatment (EVT) for patients with ischemic stroke. Design, Setting, and Participants: This phase 1b/2a, double-blind, randomized, placebo-controlled study was conducted at 15 sites in Spain and France from 2020 to 2022. Participants included patients aged 18 to 90 years who had ischemic stroke due to large vessel occlusion and were seen within 6 hours after stroke onset; other criteria were an Alberta Stroke Program Early CT Score of 6 to 10, estimated infarct core volume on baseline computed tomography perfusion of 5 to 70 mL, and the intention to undergo EVT. During the study period, 4174 patients underwent EVT. Interventions: In phase 1b, 0.025, 0.05, 0.1, or 0.2 mg/kg of ApTOLL or placebo; in phase 2a, 0.05 or 0.2 mg/kg of ApTOLL or placebo; and in both phases, treatment with EVT and intravenous thrombolysis if indicated. Main Outcomes and Measures: The primary end point was the safety of ApTOLL based on death, symptomatic intracranial hemorrhage (sICH), malignant stroke, and recurrent stroke. Secondary efficacy end points included final infarct volume (via MRI at 72 hours), NIHSS score at 72 hours, and disability at 90 days (modified Rankin Scale [mRS] score). Results: In phase Ib, 32 patients were allocated evenly to the 4 dose groups. After phase 1b was completed with no safety concerns, 2 doses were selected for phase 2a; these 119 patients were randomized to receive ApTOLL, 0.05 mg/kg (n = 36); ApTOLL, 0.2 mg/kg (n = 36), or placebo (n = 47) in a 1:1:√2 ratio. The pooled population of 139 patients had a mean (SD) age of 70 (12) years, 81 patients (58%) were male, and 58 (42%) were female. The primary end point occurred in 16 of 55 patients (29%) receiving placebo (10 deaths [18.2%], 4 sICH [7.3%], 4 malignant strokes [7.3%], and 2 recurrent strokes [3.6%]); in 15 of 42 patients (36%) receiving ApTOLL, 0.05 mg/kg (11 deaths [26.2%], 3 sICH [7.2%], 2 malignant strokes [4.8%], and 2 recurrent strokes [4.8%]); and in 6 of 42 patients (14%) receiving ApTOLL, 0.2 mg/kg (2 deaths [4.8%], 2 sICH [4.8%], and 3 recurrent strokes [7.1%]). ApTOLL, 0.2 mg/kg, was associated with lower NIHSS score at 72 hours (mean difference log-transformed vs placebo, -45%; 95% CI, -67% to -10%), smaller final infarct volume (mean difference log-transformed vs placebo, -42%; 95% CI, -66% to 1%), and lower degrees of disability at 90 days (common odds ratio for a better outcome vs placebo, 2.44; 95% CI, 1.76 to 5.00). Conclusions and Relevance: In acute ischemic stroke, 0.2 mg/kg of ApTOLL administered within 6 hours of onset in combination with EVT was safe and associated with a potential meaningful clinical effect, reducing mortality and disability at 90 days compared with placebo. These preliminary findings await confirmation from larger pivotal trials. Trial Registration: ClinicalTrials.gov Identifier: NCT04734548.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/complicações , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Infarto Cerebral/complicações , Hemorragias Intracranianas/etiologia , Trombectomia/métodos , Procedimentos Endovasculares/métodos
18.
Curr HIV Res ; 20(1): 7-19, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34503417

RESUMO

Human Immunodeficiency Virus (HIV) infection continues to be a significant health burden in many countries around the world. Current HIV treatment through a combination of different antiretroviral drugs (cART) effectively suppresses viral replication, but drug resistance and crossresistance are significant challenges. This has prompted the search for novel targets and agents, such as nucleic acid aptamers. Nucleic acid aptamers are oligonucleotides that attach to the target sites with high affinity and specificity. This review provides a target-by-target account of research into anti-HIV aptamers and summarises the challenges and prospects of this therapeutic strategy, specifically in the unique context of HIV infection.


Assuntos
Aptâmeros de Nucleotídeos , Infecções por HIV , Ácidos Nucleicos , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/uso terapêutico , Humanos , Ácidos Nucleicos/farmacologia , Ácidos Nucleicos/uso terapêutico , Oligonucleotídeos/farmacologia , Oligonucleotídeos/uso terapêutico , Replicação Viral
19.
J Invest Dermatol ; 142(8): 2238-2248.e8, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34979109

RESUMO

Chronic wounds represent a major health problem worldwide. Some of the available therapies based on recombinant proteins usually fail owing to the hostile environment found at the wound bed. Aptamers appear as an attractive alternative to recombinant factors owing in part to their stability, sensitivity, specificity, and low-cost production. In this study, the Cell-Systematic Evolution of Ligands by EXponential Enrichment technology was employed to generate aptamers that specifically recognize and modulate the function of the FPR2, a receptor expressed in a variety of cells involved in wound repair. Three aptamers were obtained that specifically bound to FPR2 stable transfectants generated in HaCaT cells. The targeted aptamers were shown to act as FPR2 agonists in different in vitro functional assays, including wound healing assays, and elicited a similar pattern of response to that obtained with other known FPR2 peptide agonists, such as the human LL37 cathelicidin. We have also obtained in vivo evidence for the prohealing activities of one of these FPR2 aptamers in a skin-humanized mouse model developed by us, previously shown to accurately recreate the main phases of physiological human wound repair process. In conclusion, we provide evidence of the potential therapeutic value of FPR2 aptamers for cutaneous repair.


Assuntos
Aptâmeros de Nucleotídeos , Receptores de Formil Peptídeo , Animais , Humanos , Ligantes , Camundongos , Receptores de Formil Peptídeo/agonistas , Receptores de Formil Peptídeo/genética , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/agonistas , Receptores de Lipoxinas/genética , Receptores de Lipoxinas/metabolismo , Cicatrização
20.
Clin Pediatr (Phila) ; 61(4): 335-346, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35152770

RESUMO

Moderate to vigorous physical activity (MVPA), sports, and reduced screen time are associated with favorable youth risk profiles. We evaluated the association of MVPA, sports, and screen time with adolescent behaviors among pediatric emergency department youth. Adolescents were assessed for alcohol/drug use, risky behavior, conduct disorder, and depressive mood. MVPA was activity for ≥5 days/week and ≥60 minutes/day. Increased screen time was ≥3 hours/day computer/TV use for non-schoolwork. Multivariable regression studied association between MVPA, sports, and increased screen time and outcomes adjusting for demographics and academic achievement. Older age and lower academic achievement were significantly associated with risky behaviors, conduct disorder, and depression. Youth who endorsed MVPA and sports participation had less depression (odds ratio [OR] = 0.76; confidence interval [CI] = 0.66-0.87). Increased screen time was associated with conduct disorder (OR = 1.6; CI = 1.3-2.1), depression (OR = 1.2; CI = 1.0-1.4), and drug use (OR = 1.8; CI = 1.1-2.8). In pediatric emergency department youth, MVPA and sports participation is associated with less depression. Increased screen time is associated with conduct disorders, depression, and drug use.


Assuntos
Comportamento do Adolescente , Esportes , Adolescente , Criança , Serviço Hospitalar de Emergência , Exercício Físico , Humanos , Tempo de Tela
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