Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Mol Psychiatry ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806690

RESUMO

Major depression (MD) and obesity are complex genetic disorders that are frequently comorbid. However, the study of both diseases concurrently remains poorly addressed and therefore the underlying genetic mechanisms involved in this comorbidity remain largely unknown. Here we examine the contribution of common and rare variants to this comorbidity through a next-generation sequencing (NGS) approach. Specific genomic regions of interest in MD and obesity were sequenced in a group of 654 individuals from the PISMA-ep epidemiological study. We obtained variants across the entire frequency spectrum and assessed their association with comorbid MD and obesity, both at variant and gene levels. We identified 55 independent common variants and a burden of rare variants in 4 genes (PARK2, FGF21, HIST1H3D and RSRC1) associated with the comorbid phenotype. Follow-up analyses revealed significantly enriched gene-sets associated with biological processes and pathways involved in metabolic dysregulation, hormone signaling and cell cycle regulation. Our results suggest that, while risk variants specific to the comorbid phenotype have been identified, the genes functionally impacted by the risk variants share cell biological processes and signaling pathways with MD and obesity phenotypes separately. To the best of our knowledge, this is the first study involving a targeted sequencing approach toward the study of the comorbid MD and obesity. The framework presented here allowed a deep characterization of the genetics of the co-occurring MD and obesity, revealing insights into the mutational and functional profile that underlies this comorbidity and contributing to a better understanding of the relationship between these two disabling disorders.

2.
Hum Genomics ; 17(1): 20, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894999

RESUMO

BACKGROUND: Despite being a very common type of genetic variation, the distribution of copy-number variations (CNVs) in the population is still poorly understood. The knowledge of the genetic variability, especially at the level of the local population, is a critical factor for distinguishing pathogenic from non-pathogenic variation in the discovery of new disease variants. RESULTS: Here, we present the SPAnish Copy Number Alterations Collaborative Server (SPACNACS), which currently contains copy number variation profiles obtained from more than 400 genomes and exomes of unrelated Spanish individuals. By means of a collaborative crowdsourcing effort whole genome and whole exome sequencing data, produced by local genomic projects and for other purposes, is continuously collected. Once checked both, the Spanish ancestry and the lack of kinship with other individuals in the SPACNACS, the CNVs are inferred for these sequences and they are used to populate the database. A web interface allows querying the database with different filters that include ICD10 upper categories. This allows discarding samples from the disease under study and obtaining pseudo-control CNV profiles from the local population. We also show here additional studies on the local impact of CNVs in some phenotypes and on pharmacogenomic variants. SPACNACS can be accessed at: http://csvs.clinbioinfosspa.es/spacnacs/ . CONCLUSION: SPACNACS facilitates disease gene discovery by providing detailed information of the local variability of the population and exemplifies how to reuse genomic data produced for other purposes to build a local reference database.


Assuntos
Crowdsourcing , Variações do Número de Cópias de DNA , Variações do Número de Cópias de DNA/genética , Genômica , Fenótipo , Bases de Dados Factuais
3.
BMC Cancer ; 23(1): 47, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639629

RESUMO

BACKGROUND: New concepts for a more effective anti-cancer therapy are urgently needed. Experimental flaws represent a major counter player of this development and lead to inaccurate and unreproducible data as well as unsuccessful translation of research approaches into clinics. In a previous study we have created epithelial cell cultures from head and neck squamous cell carcinoma (HNSCC) tissue. METHODS: We characterize primary cell populations isolated from human papillomavirus positive HNSCC tissue for their marker expression by RT-qPCR, flow cytometry, and immunofluorescence staining. Their sensitivity to MDM2-inhibition was measured using cell viability assays. RESULTS: Primary HNSCC cell cultures showed the delayed formation of spheroids at higher passages. These spheroids mimicked the morphology and growth characteristics of other established HNSCC spheroid models. However, expression of epithelial and mesenchymal markers could not be detected in these cells despite the presence of the HNSCC stem cell marker aldehyde dehydrogenase 1 family member A1. Instead, strong expression of B- and T-lymphocytes markers was observed. Flow cytometry analysis revealed a heterogeneous mixture of CD3 + /CD25 + T-lymphocytes and CD19 + B-lymphocytes at a ratio of 4:1 at passage 5 and transformed lymphocytes at late passages (≥ passage 12) with CD45 + CD19 + CD20 + , of which around 10 to 20% were CD3 + CD25 + CD56 + . Interestingly, the whole population was FOXP3-positive indicative of regulatory B-cells (Bregs). Expression of transcripts specific for the Epstein-Barr-virus (EBV) was detected to increase in these spheroid cells along late passages, and this population was vulnerable to MDM2 inhibition. HPV + HNSCC cells but not EBV + lymphocytes were detected to engraft into immunodeficient mice. CONCLUSIONS: In this study we present a primary cell culture of EBV-infected tumor-infiltrating B-lymphocytes, which could be used to study the role of these cells in tumor biology in future research projects. Moreover, by describing the detailed characteristics of these cells, we aim to caution other researchers in the HNSCC field to test for EBV-infected lymphocyte contaminations in primary cell cultures ahead of further experiments. Especially researchers who are interested in TIL-based adopted immunotherapy should exclude these cells in their primary tumor models, e.g. by MDM2-inhibitor treatment. BI-12-derived xenograft tumors represent a suitable model for in vivo targeting studies.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias de Cabeça e Pescoço , Humanos , Camundongos , Animais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Herpesvirus Humano 4 , Linfócitos , Proliferação de Células , Técnicas de Cultura de Células
4.
Epidemiol Infect ; 151: e201, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37997654

RESUMO

This study aimed to assess the ability of a real-time reverse transcription polymerase chain reaction (RT-PCR) with multiple targets to detect SARS-CoV-2 and its variants in a single test. Nasopharyngeal specimens were collected from patients in Granada, Spain, between January 2021 and December 2022. Five allele-specific RT-PCR kits were used sequentially, with each kit designed to detect a predominant variant at the time. When the Alpha variant was dominant, the kit included the HV69/70 deletion, E and N genes. When Delta replaced Alpha, the kit incorporated the L452R mutation in addition to E and N genes. When Omicron became dominant, L452R was replaced with the N679K mutation. Before incorporating each variant kit, a comparative analysis was carried out with SARS-CoV-2 whole genome sequencing (WGS). The results demonstrated that RT-PCR with multiple targets can provide rapid and effective detection of SARS-CoV-2 and its variants in a single test. A very high degree of agreement (96.2%) was obtained between the comparison of RT-PCR and WGS. Allele-specific RT-PCR assays make it easier to implement epidemiological surveillance systems for effective public health decision making.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/genética , Alelos , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Teste para COVID-19
5.
Nucleic Acids Res ; 49(D1): D1130-D1137, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-32990755

RESUMO

The knowledge of the genetic variability of the local population is of utmost importance in personalized medicine and has been revealed as a critical factor for the discovery of new disease variants. Here, we present the Collaborative Spanish Variability Server (CSVS), which currently contains more than 2000 genomes and exomes of unrelated Spanish individuals. This database has been generated in a collaborative crowdsourcing effort collecting sequencing data produced by local genomic projects and for other purposes. Sequences have been grouped by ICD10 upper categories. A web interface allows querying the database removing one or more ICD10 categories. In this way, aggregated counts of allele frequencies of the pseudo-control Spanish population can be obtained for diseases belonging to the category removed. Interestingly, in addition to pseudo-control studies, some population studies can be made, as, for example, prevalence of pharmacogenomic variants, etc. In addition, this genomic data has been used to define the first Spanish Genome Reference Panel (SGRP1.0) for imputation. This is the first local repository of variability entirely produced by a crowdsourcing effort and constitutes an example for future initiatives to characterize local variability worldwide. CSVS is also part of the GA4GH Beacon network. CSVS can be accessed at: http://csvs.babelomics.org/.


Assuntos
Crowdsourcing , Bases de Dados Genéticas , Genética Populacional/métodos , Genoma Humano , Software , Alelos , Mapeamento Cromossômico , Exoma , Frequência do Gene , Variação Genética , Genômica , Humanos , Internet , Medicina de Precisão/métodos , Espanha
6.
Int J Mol Sci ; 24(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36768253

RESUMO

The circadian clock is a regulatory system, with a periodicity of approximately 24 h, that generates rhythmic changes in many physiological processes. Increasing evidence links chronodisruption with aberrant functionality in clock gene expression, resulting in multiple diseases, including cancer. In this context, tumor cells have an altered circadian machinery compared to normal cells, which deregulates the cell cycle, repair mechanisms, energy metabolism and other processes. Melatonin is the main hormone produced by the pineal gland, whose production and secretion oscillates in accordance with the light:dark cycle. In addition, melatonin regulates the expression of clock genes, including those in cancer cells, which could play a key role in the numerous oncostatic effects of this hormone. This review aims to describe and clarify the role of clock genes in cancer, as well as the possible mechanisms of the action of melatonin through which it regulates the expression of the tumor's circadian machinery, in order to propose future anti-neoplastic clinical treatments.


Assuntos
Relógios Circadianos , Melatonina , Neoplasias , Glândula Pineal , Melatonina/metabolismo , Ritmo Circadiano/genética , Glândula Pineal/metabolismo , Relógios Circadianos/genética , Fotoperíodo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo
7.
Int J Mol Sci ; 24(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37834478

RESUMO

The circadian clock is a regulatory system, with a periodicity of approximately 24 h, which generates rhythmic changes in many physiological processes, including mitochondrial activity. Increasing evidence links chronodisruption with aberrant functionality in clock gene expression, resulting in multiple diseases such as cancer. Melatonin, whose production and secretion oscillates according to the light-dark cycle, is the principal regulator of clock gene expression. In addition, the oncostatic effects of melatonin correlate with an increase in mitochondrial activity. However, the direct links between circadian clock gene expression, mitochondrial activity, and the antiproliferative effects of melatonin in cancers, including head and neck squamous cell carcinoma (HNSCC), remain largely unknown. In this study, we analyzed the effects of melatonin on HNSCC cell lines (Cal-27 and SCC9), which were treated with 500 and 1000 µM melatonin. We found that the antiproliferative effect of melatonin is not mediated by the Bmal1 clock gene. Additionally, high doses of melatonin were observed to result in resynchronization of oscillatory circadian rhythm genes (Per2 and Sirt1). Surprisingly, the resynchronizing effect of melatonin on Per2 and Sirt1 did not produce alterations in the oscillation of mitochondrial respiratory activity. These results increase our understanding of the possible antiproliferative mechanisms in melatonin in the treatment of head and neck squamous cell carcinoma and suggest that its antiproliferative effects are independent of clock genes but are directly related to mitochondrial activity.


Assuntos
Neoplasias de Cabeça e Pescoço , Melatonina , Neoplasias de Células Escamosas , Humanos , Melatonina/farmacologia , Melatonina/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Sirtuína 1 , Ritmo Circadiano/fisiologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética
8.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36768752

RESUMO

Recombination is an evolutionary strategy to quickly acquire new viral properties inherited from the parental lineages. The systematic survey of the SARS-CoV-2 genome sequences of the Andalusian genomic surveillance strategy has allowed the detection of an unexpectedly high number of co-infections, which constitute the ideal scenario for the emergence of new recombinants. Whole genome sequence of SARS-CoV-2 has been carried out as part of the genomic surveillance programme. Sample sources included the main hospitals in the Andalusia region. In addition to the increase of co-infections and known recombinants, three novel SARS-CoV-2 delta-omicron and omicron-omicron recombinant variants with two break points have been detected. Our observations document an epidemiological scenario in which co-infection and recombination are detected more frequently. Finally, we describe a family case in which co-infection is followed by the detection of a recombinant made from the two co-infecting variants. This increased number of recombinants raises the risk of emergence of recombinant variants with increased transmissibility and pathogenicity.


Assuntos
COVID-19 , Coinfecção , Humanos , Coinfecção/epidemiologia , COVID-19/epidemiologia , SARS-CoV-2/genética , Evolução Biológica , Genômica
9.
J Pineal Res ; 73(3): e12824, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35986493

RESUMO

The oncostatic effects of melatonin correlate with increased reactive oxygen species (ROS) levels, but how melatonin induces this ROS generation is unknown. In the present study, we aimed to elucidate the two seemingly opposing actions of melatonin regarding its relationship with free radicals. We analyzed the effects of melatonin on head and neck squamous cell carcinoma cell lines (Cal-27 and SCC-9), which were treated with 0.5 or 1 mM melatonin. We further examined the potential effects of melatonin to induce ROS and apoptosis in Cal-27 xenograft mice. Here we report that melatonin mediates apoptosis in head and neck cancer by driving mitochondrial reverse electron transport (RET) to induce ROS production. Melatonin-induced changes in tumoral metabolism led to increased mitochondrial activity, which, in turn, induced ROS-dependent mitochondrial uncoupling. Interestingly, mitochondrial complex inhibitors, including rotenone, abolished the ROS elevation indicating that melatonin increased ROS generation via RET. Melatonin also increased membrane potential and CoQ10 H2 /CoQ10 ratio to elevate mitochondrial ROS production, which are essential conditions for RET. We found that genetic manipulation of cancer cells with alternative oxidase, which transfers electrons from QH2 to oxygen, inhibited melatonin-induced ROS generation, and apoptosis. RET restored the melatonin-induced oncostatic effect, highlighting the importance of RET as the site of ROS production. These results illustrate that RET and ROS production are crucial factors in melatonin's effects in cancer cells and establish the dual effect of melatonin in protecting normal cells and inducing apoptosis in cancer cells.


Assuntos
Neoplasias de Cabeça e Pescoço , Melatonina , Animais , Apoptose , Transporte de Elétrons , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Melatonina/farmacologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo
10.
Int J Mol Sci ; 20(19)2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31597233

RESUMO

When exposed to hostile environments such as radiation, physical injuries, chemicals, pollution, and microorganisms, the skin requires protective chemical molecules and pathways. Melatonin, a highly conserved ancient molecule, plays a crucial role in the maintenance of skin. As human skin has functional melatonin receptors and also acts as a complete system that is capable of producing and regulating melatonin synthesis, melatonin is a promising candidate for its maintenance and protection. Below, we review the studies of new metabolic pathways involved in the protective functions of melatonin in dermal cells. We also discuss the advantages of the topical use of melatonin for therapeutic purposes and skin protection. In our view, endogenous intracutaneous melatonin production, together with topically-applied exogenous melatonin and its metabolites, represent two of the most potent defense systems against external damage to the skin.


Assuntos
Melatonina/metabolismo , Melatonina/farmacologia , Substâncias Protetoras/metabolismo , Substâncias Protetoras/farmacologia , Pele/metabolismo , Administração Tópica , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Humanos , Melatonina/administração & dosagem , Redes e Vias Metabólicas , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/administração & dosagem , Pele/efeitos dos fármacos
11.
J Pineal Res ; 64(3)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29247557

RESUMO

Head and neck squamous cell carcinoma (HNSCC) clearly involves activation of the Akt mammalian target of rapamycin (mTOR) signalling pathway. However, the effectiveness of treatment with the mTOR inhibitor rapamycin is often limited by chemoresistance. Melatonin suppresses neoplastic growth via different mechanisms in a variety of tumours. In this study, we aimed to elucidate the effects of melatonin on rapamycin-induced HNSCC cell death and to identify potential cross-talk pathways. We analysed the dose-dependent effects of melatonin in rapamycin-treated HNSCC cell lines (Cal-27 and SCC-9). These cells were treated with 0.1, 0.5 or 1 mmol/L melatonin combined with 20 nM rapamycin. We further examined the potential synergistic effects of melatonin with rapamycin in Cal-27 xenograft mice. Relationships between inhibition of the mTOR pathway, reactive oxygen species (ROS), and apoptosis and mitophagy reportedly increased the cytotoxic effects of rapamycin in HNSCC. Our results demonstrated that combined treatment with rapamycin and melatonin blocked the negative feedback loop from the specific downstream effector of mTOR activation S6K1 to Akt signalling, which decreased cell viability, proliferation and clonogenic capacity. Interestingly, combined treatment with rapamycin and melatonin-induced changes in mitochondrial function, which were associated with increased ROS production, increasing apoptosis and mitophagy. This led to increase cell death and cellular differentiation. Our data further indicated that melatonin administration reduced rapamycin-associated toxicity to healthy cells. Overall, our findings suggested that melatonin could be used as an adjuvant agent with rapamycin, improving effectiveness while minimizing its side effects.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Mitofagia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melatonina/farmacologia , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirolimo/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Mol Biol Evol ; 33(5): 1205-18, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26764160

RESUMO

Recent results from large-scale genomic projects suggest that allele frequencies, which are highly relevant for medical purposes, differ considerably across different populations. The need for a detailed catalog of local variability motivated the whole-exome sequencing of 267 unrelated individuals, representative of the healthy Spanish population. Like in other studies, a considerable number of rare variants were found (almost one-third of the described variants). There were also relevant differences in allelic frequencies in polymorphic variants, including ∼10,000 polymorphisms private to the Spanish population. The allelic frequencies of variants conferring susceptibility to complex diseases (including cancer, schizophrenia, Alzheimer disease, type 2 diabetes, and other pathologies) were overall similar to those of other populations. However, the trend is the opposite for variants linked to Mendelian and rare diseases (including several retinal degenerative dystrophies and cardiomyopathies) that show marked frequency differences between populations. Interestingly, a correspondence between differences in allelic frequencies and disease prevalence was found, highlighting the relevance of frequency differences in disease risk. These differences are also observed in variants that disrupt known drug binding sites, suggesting an important role for local variability in population-specific drug resistances or adverse effects. We have made the Spanish population variant server web page that contains population frequency information for the complete list of 170,888 variant positions we found publicly available (http://spv.babelomics.org/), We show that it if fundamental to determine population-specific variant frequencies to distinguish real disease associations from population-specific polymorphisms.


Assuntos
Doença/genética , Exoma , Bases de Dados de Ácidos Nucleicos , Resistência a Medicamentos/genética , Frequência do Gene , Predisposição Genética para Doença , Variação Genética , Genética Populacional/métodos , Humanos , Internet , Testes Farmacogenômicos , Polimorfismo Genético , Espanha/epidemiologia
13.
J Pineal Res ; 63(2)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28423196

RESUMO

Neural stem cells (NSCs) are regarded as a promising therapeutic approach to protecting and restoring damaged neurons in neurodegenerative diseases (NDs) such as Parkinson's disease and Alzheimer's disease (PD and AD, respectively). However, new research suggests that NSC differentiation is required to make this strategy effective. Several studies have demonstrated that melatonin increases mature neuronal markers, which reflects NSC differentiation into neurons. Nevertheless, the possible involvement of mitochondria in the effects of melatonin during NSC differentiation has not yet been fully established. We therefore tested the impact of melatonin on NSC proliferation and differentiation in an attempt to determine whether these actions depend on modulating mitochondrial activity. We measured proliferation and differentiation markers, mitochondrial structural and functional parameters as well as oxidative stress indicators and also evaluated cell transplant engraftment. This enabled us to show that melatonin (25 µM) induces NSC differentiation into oligodendrocytes and neurons. These effects depend on increased mitochondrial mass/DNA/complexes, mitochondrial respiration, and membrane potential as well as ATP synthesis in NSCs. It is also interesting to note that melatonin prevented oxidative stress caused by high levels of mitochondrial activity. Finally, we found that melatonin enriches NSC engraftment in the ND mouse model following transplantation. We concluded that a combined therapy involving transplantation of NSCs pretreated with pharmacological doses of melatonin could efficiently restore neuronal cell populations in PD and AD mouse models depending on mitochondrial activity promotion.


Assuntos
Doença de Alzheimer , Diferenciação Celular/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Melatonina/farmacologia , Mitocôndrias/metabolismo , Células-Tronco Neurais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Animais , Antígenos de Diferenciação/biossíntese , Masculino , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Células-Tronco Neurais/transplante , Neurônios/metabolismo , Neurônios/patologia
14.
Int J Mol Sci ; 18(5)2017 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-28481279

RESUMO

The current treatment for cervico-facial cancer involves radio and/or chemotherapy. Unfortunately, cancer therapies can lead to local and systemic complications such as mucositis, which is the most common dose-dependent complication in the oral cavity and gastrointestinal tract. Mucositis can cause a considerably reduced quality of life in cancer patients already suffering from physical and psychological exhaustion. However, the role of melatonin in the treatment of mucositis has recently been investigated, and offers an effective alternative therapy in the prevention and/or management of radio and/or chemotherapy-induced mucositis. This review focuses on the pathobiology and management of mucositis in order to improve the quality of cancer patients' lives.


Assuntos
Antioxidantes/uso terapêutico , Melatonina/uso terapêutico , Estomatite/tratamento farmacológico , Animais , Antioxidantes/administração & dosagem , Géis/química , Humanos , Melatonina/administração & dosagem , Estomatite/etiologia
15.
Diabetologia ; 59(4): 755-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26813254

RESUMO

AIMS/HYPOTHESIS: A strategy to enhance pancreatic islet functional beta cell mass (BCM) while restraining inflammation, through the manipulation of molecular and cellular targets, would provide a means to counteract the deteriorating glycaemic control associated with diabetes mellitus. The aims of the current study were to investigate the therapeutic potential of such a target, the islet-enriched and diabetes-linked transcription factor paired box 4 (PAX4), to restrain experimental autoimmune diabetes (EAD) in the RIP-B7.1 mouse model background and to characterise putative cellular mechanisms associated with preserved BCM. METHODS: Two groups of RIP-B7.1 mice were genetically engineered to: (1) conditionally express either PAX4 (BPTL) or its diabetes-linked mutant variant R129W (mutBPTL) using doxycycline (DOX); and (2) constitutively express luciferase in beta cells through the use of RIP. Mice were treated or not with DOX, and EAD was induced by immunisation with a murine preproinsulin II cDNA expression plasmid. The development of hyperglycaemia was monitored for up to 4 weeks following immunisation and alterations in the BCM were assessed weekly by non-invasive in vivo bioluminescence intensity (BLI). In parallel, BCM, islet cell proliferation and apoptosis were evaluated by immunocytochemistry. Alterations in PAX4- and PAX4R129W-mediated islet gene expression were investigated by microarray profiling. PAX4 preservation of endoplasmic reticulum (ER) homeostasis was assessed using thapsigargin, electron microscopy and intracellular calcium measurements. RESULTS: PAX4 overexpression blunted EAD, whereas the diabetes-linked mutant variant PAX4R129W did not convey protection. PAX4-expressing islets exhibited reduced insulitis and decreased beta cell apoptosis, correlating with diminished DNA damage and increased islet cell proliferation. Microarray profiling revealed that PAX4 but not PAX4R129W targeted expression of genes implicated in cell cycle and ER homeostasis. Consistent with the latter, islets overexpressing PAX4 were protected against thapsigargin-mediated ER-stress-related apoptosis. Luminal swelling associated with ER stress induced by thapsigargin was rescued in PAX4-overexpressing beta cells, correlating with preserved cytosolic calcium oscillations in response to glucose. In contrast, RNA interference mediated repression of PAX4-sensitised MIN6 cells to thapsigargin cell death. CONCLUSIONS/INTERPRETATION: The coordinated regulation of distinct cellular pathways particularly related to ER homeostasis by PAX4 not achieved by the mutant variant PAX4R129W alleviates beta cell degeneration and protects against diabetes mellitus. The raw data for the RNA microarray described herein are accessible in the Gene Expression Omnibus database under accession number GSE62846.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Homeodomínio/metabolismo , Células Secretoras de Insulina/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Animais , Apoptose/fisiologia , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 1/patologia , Feminino , Células Secretoras de Insulina/patologia , Masculino , Camundongos , Camundongos Mutantes
16.
Bioinformatics ; 30(12): 1767-8, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24578402

RESUMO

MOTIVATION: Targeted enrichment sequencing by next-generation sequencing is a common approach to interrogate specific loci or the whole exome in the human genome. The efficiency and the lack of bias in the enrichment process need to be assessed as a quality control step before performing downstream analysis of the sequence data. Tools that can report on the sensitivity, specificity, uniformity and other enrichment-specific features are needed. RESULTS: We have implemented the next-generation sequencing data Capture Assessment Tool (ngsCAT), a tool that takes the information of the mapped reads and the coordinates of the targeted regions as input files, and generates a report with metrics and figures that allows the evaluation of the efficiency of the enrichment process. The tool can also take as input the information of two samples allowing the comparison of two different experiments. AVAILABILITY AND IMPLEMENTATION: Documentation and downloads for ngsCAT can be found at http://www.bioinfomgp.org/ngscat.


Assuntos
Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Software , Exoma , Humanos
17.
Nucleic Acids Res ; 41(1): e26, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23066102

RESUMO

Multiple sequence alignments (MSAs) have become one of the most studied approaches in bioinformatics to perform other outstanding tasks such as structure prediction, biological function analysis or next-generation sequencing. However, current MSA algorithms do not always provide consistent solutions, since alignments become increasingly difficult when dealing with low similarity sequences. As widely known, these algorithms directly depend on specific features of the sequences, causing relevant influence on the alignment accuracy. Many MSA tools have been recently designed but it is not possible to know in advance which one is the most suitable for a particular set of sequences. In this work, we analyze some of the most used algorithms presented in the bibliography and their dependences on several features. A novel intelligent algorithm based on least square support vector machine is then developed to predict how accurate each alignment could be, depending on its analyzed features. This algorithm is performed with a dataset of 2180 MSAs. The proposed system first estimates the accuracy of possible alignments. The most promising methodologies are then selected in order to align each set of sequences. Since only one selected algorithm is run, the computational time is not excessively increased.


Assuntos
Alinhamento de Sequência/métodos , Máquina de Vetores de Suporte , Bases de Dados Genéticas , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes , Análise de Sequência de Proteína
18.
Bioinformatics ; 29(17): 2112-21, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23793754

RESUMO

MOTIVATION: Multiple sequence alignments (MSAs) are widely used approaches in bioinformatics to carry out other tasks such as structure predictions, biological function analyses or phylogenetic modeling. However, current tools usually provide partially optimal alignments, as each one is focused on specific biological features. Thus, the same set of sequences can produce different alignments, above all when sequences are less similar. Consequently, researchers and biologists do not agree about which is the most suitable way to evaluate MSAs. Recent evaluations tend to use more complex scores including further biological features. Among them, 3D structures are increasingly being used to evaluate alignments. Because structures are more conserved in proteins than sequences, scores with structural information are better suited to evaluate more distant relationships between sequences. RESULTS: The proposed multiobjective algorithm, based on the non-dominated sorting genetic algorithm, aims to jointly optimize three objectives: STRIKE score, non-gaps percentage and totally conserved columns. It was significantly assessed on the BAliBASE benchmark according to the Kruskal-Wallis test (P < 0.01). This algorithm also outperforms other aligners, such as ClustalW, Multiple Sequence Alignment Genetic Algorithm (MSA-GA), PRRP, DIALIGN, Hidden Markov Model Training (HMMT), Pattern-Induced Multi-sequence Alignment (PIMA), MULTIALIGN, Sequence Alignment Genetic Algorithm (SAGA), PILEUP, Rubber Band Technique Genetic Algorithm (RBT-GA) and Vertical Decomposition Genetic Algorithm (VDGA), according to the Wilcoxon signed-rank test (P < 0.05), whereas it shows results not significantly different to 3D-COFFEE (P > 0.05) with the advantage of being able to use less structures. Structural information is included within the objective function to evaluate more accurately the obtained alignments. AVAILABILITY: The source code is available at http://www.ugr.es/~fortuno/MOSAStrE/MO-SAStrE.zip.


Assuntos
Algoritmos , Alinhamento de Sequência/métodos , Análise de Sequência de Proteína , Bases de Dados de Proteínas , Filogenia , Conformação Proteica , Proteínas/classificação
19.
Dig Dis Sci ; 59(11): 2714-20, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25069573

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy associated with poor survival rates. Fast detection of PDAC appears to be the most relevant strategy to improve the long-term survival of patients. AIMS: Our objective was to identify new markers in peripheral blood that differentiates between PDAC patients and healthy controls. METHODS: Peripheral blood samples from PDAC patients (n = 18) and controls (n = 18) were analyzed by whole genome cDNA microarray hybridization. The most relevant genes were validated by quantitative real-time PCR (RT-qPCR) in the same set of samples. Finally, our gene prediction set was tested in a blinded set of new peripheral blood samples (n = 30). RESULTS: Microarray studies identified 87 genes differentially expressed in peripheral blood samples from PDAC patients. Four of these genes were selected for analysis by RT-qPCR, which confirmed the previously observed changes. In our blinded validation study, the combination of CLEC4D and IRAK3 predicted the diagnosis of PDAC with 93 % accuracy, with a sensitivity of 86 % and specificity of 100 %. CONCLUSIONS: Peripheral blood gene expression profiling is an useful tool for the diagnosis of PDAC. We present a validated four-gene predictor set (ANKRD22, CLEC4D, VNN1, and IRAK3) that may be useful in PDAC diagnosis.


Assuntos
Carcinoma Ductal Pancreático/sangue , Neoplasias Pancreáticas/sangue , Transcriptoma , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/metabolismo
20.
Health Sci Rep ; 7(3): e1965, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38524774

RESUMO

Background and Aim: Until the May 2022 Monkeypox (MPXV) outbreak, which spread rapidly to many non-endemic countries, the virus was considered a viral zoonosis limited to some African countries. The Andalusian circuit of genomic surveillance was rapidly applied to characterize the MPXV outbreak in the South of Spain. Methods: Whole genome sequencing was used to obtain the genomic profiles of samples collected across the south of Spain, representative of all the provinces of Andalusia. Phylogenetic analysis was used to study the relationship of the isolates and the available sequences of the 2022 outbreak. Results: Whole genome sequencing of a total of 160 MPXV viruses from the different provinces that reported cases were obtained. Interestingly, we report the sequences of MPXV viruses obtained from two patients who died. While one of the isolates bore no noteworthy mutations that explain a potential heightened virulence, in another patient the second consecutive genome sequence, performed after the administration of tecovirimat, uncovered a mutation within the A0A7H0DN30 gene, known to be a prime target for tecovirimat in its Vaccinia counterpart. In general, a low number of mutations were observed in the sequences reported, which were very similar to the reference of the 2022 outbreak (OX044336), as expected from a DNA virus. The samples likely correspond to several introductions of the circulating MPXV viruses from the last outbreak. The virus sequenced from one of the two patients that died presented a mutation in a gene that bears potential connections to drug resistance. This mutation was absent in the initial sequencing before treatment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA