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1.
Nature ; 622(7984): 775-783, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37821706

RESUMO

Latin America continues to be severely underrepresented in genomics research, and fine-scale genetic histories and complex trait architectures remain hidden owing to insufficient data1. To fill this gap, the Mexican Biobank project genotyped 6,057 individuals from 898 rural and urban localities across all 32 states in Mexico at a resolution of 1.8 million genome-wide markers with linked complex trait and disease information creating a valuable nationwide genotype-phenotype database. Here, using ancestry deconvolution and inference of identity-by-descent segments, we inferred ancestral population sizes across Mesoamerican regions over time, unravelling Indigenous, colonial and postcolonial demographic dynamics2-6. We observed variation in runs of homozygosity among genomic regions with different ancestries reflecting distinct demographic histories and, in turn, different distributions of rare deleterious variants. We conducted genome-wide association studies (GWAS) for 22 complex traits and found that several traits are better predicted using the Mexican Biobank GWAS compared to the UK Biobank GWAS7,8. We identified genetic and environmental factors associating with trait variation, such as the length of the genome in runs of homozygosity as a predictor for body mass index, triglycerides, glucose and height. This study provides insights into the genetic histories of individuals in Mexico and dissects their complex trait architectures, both crucial for making precision and preventive medicine initiatives accessible worldwide.


Assuntos
Bancos de Espécimes Biológicos , Genética Médica , Genoma Humano , Genômica , Hispânico ou Latino , Humanos , Glicemia/genética , Glicemia/metabolismo , Estatura/genética , Índice de Massa Corporal , Interação Gene-Ambiente , Marcadores Genéticos/genética , Estudo de Associação Genômica Ampla , Hispânico ou Latino/classificação , Hispânico ou Latino/genética , Homozigoto , México , Fenótipo , Triglicerídeos/sangue , Triglicerídeos/genética , Reino Unido , Genoma Humano/genética
2.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612604

RESUMO

Metastasis and drug resistance are major contributors to cancer-related fatalities worldwide. In ovarian cancer (OC), a staggering 70% develop resistance to the front-line therapy, cisplatin. Despite proposed mechanisms, the molecular events driving cisplatin resistance remain unclear. Dysregulated microRNAs (miRNAs) play a role in OC initiation, progression, and chemoresistance, yet few studies have compared miRNA expression in OC samples and cell lines. This study aimed to identify key miRNAs involved in the cisplatin resistance of high-grade-serous-ovarian-cancer (HGSOC), the most common gynecological malignancy. MiRNA expression profiles were conducted on RNA isolated from formalin-fixed-paraffin-embedded human ovarian tumor samples and HGSOC cell lines. Nine miRNAs were identified in both sample types. Targeting these with oligonucleotide miRNA inhibitors (OMIs) reduced proliferation by more than 50% for miR-203a, miR-96-5p, miR-10a-5p, miR-141-3p, miR-200c-3p, miR-182-5p, miR-183-5p, and miR-1206. OMIs significantly reduced migration for miR-183-5p, miR-203a, miR-296-5p, and miR-1206. Molecular pathway analysis revealed that the nine miRNAs regulate pathways associated with proliferation, invasion, and chemoresistance through PTEN, ZEB1, FOXO1, and SNAI2. High expression of miR-1206, miR-10a-5p, miR-141-3p, and miR-96-5p correlated with poor prognosis in OC patients according to the KM plotter database. These nine miRNAs could be used as targets for therapy and as markers of cisplatin response.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , MicroRNAs/genética , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Linhagem Celular , Oligonucleotídeos
3.
Int J Mol Sci ; 24(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769075

RESUMO

The main cause of subretinal neovascularisation in wet age-related macular degeneration (AMD) is an abnormal expression in the retinal pigment epithelium (RPE) of the vascular endothelial growth factor (VEGF). Current approaches for the treatment of AMD present considerable issues that could be overcome by encapsulating anti-VEGF drugs in suitable nanocarriers, thus providing better penetration, higher retention times, and sustained release. In this work, the ability of large pore mesoporous silica nanoparticles (LP-MSNs) to transport and protect nucleic acid molecules is exploited to develop an innovative LP-MSN-based nanosystem for the topical administration of anti-VEGF siRNA molecules to RPE cells. siRNA is loaded into LP-MSN mesopores, while the external surface of the nanodevices is functionalised with polyethylenimine (PEI) chains that allow the controlled release of siRNA and promote endosomal escape to facilitate cytosolic delivery of the cargo. The successful results obtained for VEGF silencing in ARPE-19 RPE cells demonstrate that the designed nanodevice is suitable as an siRNA transporter.


Assuntos
Nanopartículas , Fator A de Crescimento do Endotélio Vascular , RNA Interferente Pequeno/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Dióxido de Silício/metabolismo , Epitélio Pigmentado da Retina/metabolismo
4.
J Sci Food Agric ; 103(8): 3860-3870, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36308762

RESUMO

BACKGROUND: The application of chia mucilage still remains restricted due to the difficulty in achieving high extraction yields. The effect of ultrasonic-assisted extraction (UAE) conditions (temperature, seed:water ratio and time) on the rheological properties of chia mucilage extracts and the relation to the proportion of translucent phase (TP) and opaque phase (OP) of the mucilage in the extract were evaluated. RESULTS: UAE allowed the efficient extraction of chia mucilage from chia seeds. The desired overall optimal combination to maximize both yield and apparent viscosity was achieved at a seed:water ratio 1:10, a temperature of 25.3 °C and 53.7 min extraction time; the optimal conditions to obtain the maximum yield and minimum apparent viscosity were a seed:water ratio close to 1:20, temperature of 48.8 °C and 208.4 min extraction time. CONCLUSION: The results obtained in the present work demonstrated that the differences in rheological properties of chia mucilage extracts are due to the extraction methods used. Therefore, it is possible to modulate the extraction conditions in order to obtain different characteristics of the mucilage, maintaining a high extraction yield. © 2022 Society of Chemical Industry.


Assuntos
Mucilagem Vegetal , Salvia , Mucilagem Vegetal/química , Viscosidade , Ultrassom , Salvia/química , Polissacarídeos/química , Sementes/química , Extratos Vegetais/química , Água/análise
5.
Violence Vict ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35728926

RESUMO

In the study of child-to-parent violence (CPV), the perspective of the victimized aggressor has not been analyzed in depth, and the impact of different contexts of victimization even less so. The aim of this study was to examine the unique and additive effects of family victimization (direct and vicarious) and school victimization (bullying and cyberbullying) on predicting CPV toward fathers and mothers. The sample included 3,142 adolescents aged 12-18 years (M age = 14.32) from schools in southern Spain. The participants completed the Child-to-Parent Violence Questionnaire adolescent version, the Violence Exposure Scale, and the European Bullying/Cyberbullying Intervention Project Questionnaires. The findings showed that independently, both family and school victimization predicted CPV, with direct family victimization being the best predictor, and that jointly, contributed to a significant improvement in prediction, explaining approximately 20% of CPV. Furthermore, a correspondence was found between the type of violence experienced and the type of violence perpetrated. It is necessary to study the profile of the victimized aggressor in CPV in order to design interventions adapted to the specific needs of this profile.

6.
Proc Natl Acad Sci U S A ; 115(45): 11597-11602, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30348770

RESUMO

Receptor-type protein tyrosine phosphatase D (PTPRD) is a neuronal cell-adhesion molecule/synaptic specifier that has been implicated in addiction vulnerability and stimulant reward by human genomewide association and mouse cocaine-conditioned place-preference data. However, there have been no reports of effects of reduced expression on cocaine self-administration. There have been no reports of PTPRD targeting by any small molecule. There are no data about behavioral effects of any PTPRD ligand. We now report (i) robust effects of heterozygous PTPRD KO on cocaine self-administration (These data substantially extend prior conditioned place-preference data and add to the rationale for PTPRD as a target for addiction therapeutics.); (ii) identification of 7-butoxy illudalic acid analog (7-BIA) as a small molecule that targets PTPRD and inhibits its phosphatase with some specificity; (iii) lack of toxicity when 7-BIA is administered to mice acutely or with repeated dosing; (iv) reduced cocaine-conditioned place preference when 7-BIA is administered before conditioning sessions; and (v) reductions in well-established cocaine self-administration when 7-BIA is administered before a session (in WT, not PTPRD heterozygous KOs). These results add to support for PTPRD as a target for medications to combat cocaine use disorders. 7-BIA provides a lead compound for addiction therapeutics.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Cumarínicos/farmacologia , Antagonistas de Entorpecentes/farmacologia , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/genética , Recompensa , Abuso de Substâncias por Via Intravenosa/tratamento farmacológico , Animais , Cateteres de Demora , Transtornos Relacionados ao Uso de Cocaína/enzimologia , Transtornos Relacionados ao Uso de Cocaína/genética , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Condicionamento Psicológico , Cumarínicos/síntese química , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Injeções Intravenosas , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antagonistas de Entorpecentes/síntese química , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Neurônios/patologia , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/antagonistas & inibidores , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/deficiência , Autoadministração , Transdução de Sinais , Abuso de Substâncias por Via Intravenosa/enzimologia , Abuso de Substâncias por Via Intravenosa/genética , Abuso de Substâncias por Via Intravenosa/fisiopatologia , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
7.
Rheumatology (Oxford) ; 59(9): 2556-2562, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31998955

RESUMO

OBJECTIVES: Prevalence of SLE varies among studies, being influenced by study design, geographical area and ethnicity. Data about the prevalence of SLE in Spain are scarce. In the EPISER2016 study, promoted by the Spanish Society of Rheumatology, the prevalence estimate of SLE in the general adult population in Spain has been updated and its association with sociodemographic, anthropometric and lifestyle variables has been explored. METHODS: Population-based multicentre cross-sectional study, with multistage stratified and cluster random sampling. Participants were contacted by telephone to carry out a questionnaire for the screening of SLE. Investigating rheumatologists evaluated positive results (review of medical records and/or telephone interview, with medical visit if needed) to confirm the diagnosis. To calculate the prevalence and its 95% CI, the sample design was taken into account and weighing was calculated considering age, sex and geographic origin. Multivariate logistic regression models were defined to analyse which sociodemographic, anthropometric and lifestyle variables included in the telephone questionnaire were associated with the presence of SLE. RESULTS: 4916 subjects aged 20 years or over were included. 16.52% (812/4916) had a positive screening result for SLE. 12 cases of SLE were detected. The estimated prevalence was 0.21% (95% CI: 0.11, 0.40). SLE was more prevalent in the rural municipalities, with an odds ratio (OR) = 4.041 (95% CI: 1.216, 13.424). CONCLUSION: The estimated prevalence of SLE in Spain is higher than that described in most international epidemiological studies, but lower than that observed in ethnic minorities in the United States or the United Kingdom.


Assuntos
Lúpus Eritematoso Sistêmico , Adulto , Estudos Transversais , Demografia , Feminino , Humanos , Entrevistas como Assunto/métodos , Entrevistas como Assunto/estatística & dados numéricos , Estilo de Vida , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/psicologia , Masculino , Registros Médicos Orientados a Problemas/estatística & dados numéricos , Gravidade do Paciente , Prevalência , Fatores Socioeconômicos , Espanha/epidemiologia
8.
Am J Hum Genet ; 98(2): 363-72, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26833329

RESUMO

Genetic studies of intellectual disability and identification of monogenic causes of obesity in humans have made immense contribution toward the understanding of the brain and control of body mass. The leptin > melanocortin > SIM1 pathway is dysregulated in multiple monogenic human obesity syndromes but its downstream targets are still unknown. In ten individuals from six families, with overlapping 6q16.1 deletions, we describe a disorder of variable developmental delay, intellectual disability, and susceptibility to obesity and hyperphagia. The 6q16.1 deletions segregated with the phenotype in multiplex families and were shown to be de novo in four families, and there was dramatic phenotypic overlap among affected individuals who were independently ascertained without bias from clinical features. Analysis of the deletions revealed a ∼350 kb critical region on chromosome 6q16.1 that encompasses a gene for proneuronal transcription factor POU3F2, which is important for hypothalamic development and function. Using morpholino and mutant zebrafish models, we show that POU3F2 lies downstream of SIM1 and controls oxytocin expression in the hypothalamic neuroendocrine preoptic area. We show that this finding is consistent with the expression patterns of POU3F2 and related genes in the human brain. Our work helps to further delineate the neuro-endocrine control of energy balance/body mass and demonstrates that this molecular pathway is conserved across multiple species.


Assuntos
Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Obesidade/genética , Fatores do Domínio POU/genética , Deleção de Sequência , Adolescente , Adulto , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Índice de Massa Corporal , Linhagem Celular , Criança , Pré-Escolar , Cromossomos Humanos Par 6/genética , Modelos Animais de Doenças , Metabolismo Energético , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Hipotálamo/metabolismo , Masculino , Pessoa de Meia-Idade , Ocitocina/metabolismo , Fatores do Domínio POU/metabolismo , Linhagem , Fenótipo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Adulto Jovem , Peixe-Zebra
9.
Mol Syst Biol ; 14(8): e8202, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30108134

RESUMO

Identifying critical pathways governing disease progression is essential for accurate prognosis and effective therapy. We developed a broadly applicable and novel systems-level gene discovery strategy. This approach focused on constitutively active androgen receptor (AR) splice variant-driven pathways as representative of an intractable mechanism of prostate cancer (PC) therapeutic resistance. We performed a meta-analysis of human prostate samples using weighted gene co-expression network analysis combined with experimental AR variant transcriptome analyses. An AR variant-driven gene module that is upregulated during human PC progression was identified. We filtered this module by identifying genes that functionally interacted with AR variants using a high-throughput synthetic genetic array screen in Schizosaccharomyces pombe This strategy identified seven AR variant-regulated genes that also enhance AR activity and drive cancer progression. Expression of the seven genes predicted poor disease-free survival in large independent PC patient cohorts. Pharmacologic inhibition of interacting members of the gene set potently and synergistically decreased PC cell proliferation. This unbiased and novel gene discovery strategy identified a clinically relevant, oncogenic, interacting gene hub with strong prognostic and therapeutic potential in PC.


Assuntos
Carcinogênese/genética , Proliferação de Células/genética , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Linhagem Celular Tumoral , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Prognóstico , Neoplasias da Próstata/patologia , Splicing de RNA/genética , Receptores Androgênicos/química , Schizosaccharomyces/genética , Transdução de Sinais/genética
10.
Pediatr Res ; 83(1-1): 119-127, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28820871

RESUMO

BackgroundFetal alcohol syndrome (FAS) is caused by maternal alcohol consumption during pregnancy; although additional factors might be involved, as development and severity are not directly related to alcohol intake. The abnormal glycosylation caused by alcohol might play a role in FAS according to the clinical similarities shared with congenital disorders of glycosylation (CDG). Thus, mutations underlying CDG, affecting genes involved in glycosylation, could also be involved in FAS.MethodsA panel of 74 genes involved in N-glycosylation was sequenced in 25 FAS patients and 20 controls with prenatal alcohol exposure. Transferrin glycoforms were evaluated by HPLC.ResultsRare (minor allele frequency<0.009) missense/splice site variants were more frequent in FAS than controls (84% vs. 50%; P=0.034, odds ratio: 5.25, 95% confidence interval: 1.3-20.9). Remarkably, three patients, but no controls, carried variants with functional effects identified in CDG patients. Moreover, the patient with the most severe clinical phenotype was the only one carrying two variants with functional effects. Family studies support that the combination of a genetic defect and alcohol consumption during pregnancy might have a role in FAS development.ConclusionsOur study supports that the rare variants of genes involved in N-glycosylation could play a role in the development and severity of FAS under prenatal alcohol exposure.


Assuntos
Defeitos Congênitos da Glicosilação/genética , Transtornos do Espectro Alcoólico Fetal/genética , Predisposição Genética para Doença , Mutação , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Defeitos Congênitos da Glicosilação/complicações , Feminino , Variação Genética , Glicosilação , Humanos , Lactente , Masculino , Exposição Materna , Pessoa de Meia-Idade , Mães , Razão de Chances , Gravidez , Estudos Retrospectivos , Análise de Sequência de DNA , Transferrina/química
11.
J Sci Food Agric ; 98(15): 5822-5831, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29756351

RESUMO

BACKGROUND: The insecticidal and repellent effects on adult Sitophilus zeamais of 12 cinnamaldehyde-related compounds was evaluated by contact toxicity bioassays and a two-choice olfactometer. To determine non-toxicity in mammals, body weight, serum biochemical profiles, liver weight, physiological parameters, sperm motility, and histopathological data were obtained as complementary information in C57BL/6 mice treated with the best natural compound. RESULTS: Based on 24 h LC95 and LC50 values, α-methyl-cinnamaldehyde and cinnamaldehyde exhibited better insecticidal action than the other compounds. The best repellent effect was observed with α-bromo-cinnamaldehyde, which even repelled at the lowest concentration studied (0.28 µmol L-1 ). The evaluation of a quantitative structure-activity relationship found a linear relationship between the LC50 values for adult weevil toxicity and dipolo with Q values (giving the difference between orbital electronegativity carbon 1 and orbital electronegativity carbon 3 of the molecule) in cinnamaldehyde-related compounds. The polar surface and Log P descriptors also revealed a linear relationship with the S. zeamais repellent effect for cinnamaldehyde analogues. Cinnamaldehyde did not show toxicity in the parameters evaluated in mice. CONCLUSION: From the phenylpropanoid components studied, the natural compound that had the best insecticidal and repellent action against S. zeamais was cinnamaldehyde. It presented no mammalian toxicity. © 2018 Society of Chemical Industry.


Assuntos
Acroleína/análogos & derivados , Repelentes de Insetos/química , Repelentes de Insetos/toxicidade , Inseticidas/química , Inseticidas/toxicidade , Gorgulhos/efeitos dos fármacos , Acroleína/química , Acroleína/toxicidade , Animais , Feminino , Masculino , Camundongos Endogâmicos C57BL , Motilidade dos Espermatozoides/efeitos dos fármacos , Relação Estrutura-Atividade , Gorgulhos/fisiologia
13.
BMC Biotechnol ; 15: 74, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26268358

RESUMO

BACKGROUND: Fungal laccases are multicopper oxidases (MCOs) with high biotechnological potential due to their capability to oxidize a wide range of aromatic contaminants using oxygen from the air. Albeit the numerous laccase-like genes described in ascomycete fungi, ascomycete laccases have been less thoroughly studied than white-rot basidiomycetous laccases. A variety of MCO genes has recently been discovered in plant pathogenic ascomycete fungi, however little is known about the presence and function of laccases in these fungi or their potential use as biocatalysts. We aim here to identify the laccase-type oxidoreductases that might be involved in the decolorization of dyes by Leptosphaerulina sp. and to characterize them as potential biotechnological tools. RESULTS: A Leptosphaerulina fungal strain, isolated from lignocellulosic material in Colombia, produces laccase as the main ligninolytic oxidoreductase activity during decolorization of synthetic organic dyes. Four laccase-type MCO genes were partially amplified from the genomic DNA using degenerate primers based on laccase-specific signature sequences. The phylogenetic analysis showed the clustering of Lac1, Lac4 and Lac3 with ascomycete laccases, whereas Lac2 grouped with fungal ferroxidases (together with other hypothetical laccases). Lac3, the main laccase produced by Leptosphaerulina sp. in dye decolorizing and laccase-induced cultures (according to the shotgun analysis of both secretomes) was purified and characterized in this study. It is a sensu-stricto laccase able to decolorize synthetic organic dyes with high efficiency particularly in the presence of natural mediator compounds. CONCLUSIONS: The searching for laccase-type MCOs in ascomycetous families where their presence is poorly known, might provide a source of biocatalysts with potential biotechnological interest and shed light on their role in the fungus. The information provided by the use of genomic and proteomic tools must be combined with the biochemical evaluation of the enzyme to prove its catalytic activity and applicability potential.


Assuntos
Lacase/genética , Oxirredutases/genética , Filogenia , Sequência de Aminoácidos , Ascomicetos/enzimologia , Clonagem Molecular , Lacase/isolamento & purificação , Lacase/metabolismo , Oxirredução , Oxirredutases/isolamento & purificação , Oxigênio/metabolismo
14.
Am J Med Genet A ; 167A(4): 786-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25655674

RESUMO

The 10q26 deletion syndrome is a clinically heterogeneous disorder. The most common phenotypic characteristics include pre- and/or postnatal growth retardation, microcephaly, developmental delay/intellectual disability and a facial appearance consisting of a broad nasal bridge with a prominent nose, low-set malformed ears, strabismus, and a thin vermilion of the upper lip. In addition, limb and cardiac anomalies as well as urogenital anomalies are occasionally observed. In this report, we describe three unrelated females with 10q26 terminal deletions who shared clinical features of the syndrome, including urogenital defects. Cytogenetic studies showed an apparently de novo isolated deletion of the long arm of chromosome 10, with breakpoints in 10q26.1, and subsequent oligo array-CGH analysis confirmed the terminal location and defined the size of the overlapping deletions as ∼ 13.46, ∼ 9.31 and ∼ 9.17 Mb. We compared the phenotypic characteristics of the present patients with others reported to have isolated deletions and we suggest that small 10q26.2 terminal deletions may be associated with growth retardation, developmental delay/intellectual disability, craniofacial features and external genital anomalies whereas longer terminal deletions affecting the 10q26.12 and/or 10q26.13 regions may be responsible for renal/urinary tract anomalies. We propose that the haploinsufficiency of one or several genes located in the 10q26.12-q26.13 region may contribute to the renal or urinary tract pathogenesis and we highlight the importance of FGFR2 and probably of CTBP2 as candidate genes.


Assuntos
Deficiências da Aprendizagem/diagnóstico , Anormalidades Urogenitais/diagnóstico , Adolescente , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 10/genética , Hibridização Genômica Comparativa , Fácies , Feminino , Estudos de Associação Genética , Humanos , Deficiências da Aprendizagem/genética , Anormalidades Urogenitais/genética
15.
Nanomedicine ; 11(1): 39-46, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25072378

RESUMO

Blood clots when it contacts foreign surfaces following platelet activation. This can be catastrophic in clinical settings involving extracorporeal circulation such as during heart-lung bypass where blood is circulated in polyvinyl chloride tubing. Studies have shown, however, that surface-bound carbon nanotubes may prevent platelet activation, the initiator of thrombosis. We studied the blood biocompatibility of polyvinyl chloride, surface-modified with multi-walled carbon nanotubes in vitro and in vivo. Our results show that surface-bound multi-walled carbon nanotubes cause platelet activation in vitro and devastating thrombosis in an in vivo animal model of extracorporeal circulation. The mechanism of the pro-thrombotic effect likely involves direct multi-walled carbon nanotube-platelet interaction with Ca(2+)-dependant platelet activation. These experiments provide evidence, for the first time, that modification of surfaces with nanomaterials modulates blood biocompatibility in extracorporeal circulation.


Assuntos
Materiais Biocompatíveis/química , Nanomedicina/métodos , Nanotubos de Carbono/química , Animais , Coagulação Sanguínea , Plaquetas/efeitos dos fármacos , Cálcio/química , Ponte Cardiopulmonar , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Perfusão , Ativação Plaquetária , Cloreto de Polivinila/química , Proteômica , Coelhos , Propriedades de Superfície , Trombose/metabolismo
16.
Carcinogenesis ; 35(2): 324-32, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24085798

RESUMO

Platelets have been implicated in colon cancer metastasis and prognosis but the underlying molecular mechanisms remain unclear. We evaluated the role of the different mitogen-activated protein kinase (MAPK) pathways in platelet-stimulated matrix metalloproteinase-9 (MMP-9) generation and colon cancer invasion. In addition, proteins released during platelet-tumour cell interactions were studied. For this purpose, interactions of Caco-2 and HT29 cells with platelets were studied using scanning electron microscopy, aggregometry, flow cytometry and cell invasion chambers. Quantitative PCR and zymography were used to study MMP-9 gene expression and activity, respectively, whereas western blot was used to study p38MAPK. Finally, the origin of proteins during platelet-cancer cell interactions was investigated using stable isotope labelling by amino acids in cell culture (SILAC)-based proteomics. We found that platelets promoted p38MAPK phosphorylation and MMP-9 up-regulation in both cell lines, with the subsequent cell-invasion-promoting effects. Pharmacological inhibition of p38MAPK led to a significant down-regulation of MMP-9 and colon cancer cell invasiveness. Also, p38MAPK-small interfering RNA abolished the induction of platelet-stimulated MMP-9. SILAC experiments demonstrated that thrombospondin 1 (TSP1) was released mainly from platelets and clusterin by both platelets and cancer cells. Finally, inhibition of TSP1 and clusterin abolished p38MAPK phosphorylation, MMP-9 activity and platelet-stimulated colon cancer invasion. Our results indicate that platelet-secreted TSP1 and clusterin promote the signal regulation of MMP-9 in platelet-induced colonic cancer invasion via a P38MAPK-regulated pathway. These findings are relevant to the development of therapeutic approaches to preventing and reducing tumour cell metastasis induced by colon adenocarcinoma.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Plaquetas/metabolismo , Clusterina/metabolismo , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Apoptose , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Western Blotting , Células CACO-2 , Movimento Celular , Proliferação de Células , Cromatografia Líquida , Clusterina/genética , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Citometria de Fluxo , Células HT29 , Humanos , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica , Fosforilação , Proteômica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Espectrometria de Massas em Tandem , Proteínas Quinases p38 Ativadas por Mitógeno/genética
17.
Environ Microbiol ; 16(6): 1779-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24428705

RESUMO

Although homologs of the ATP-dependent Lon protease exist in all domains of life, the relevance of this protease in archaeal physiology remains a mystery. In this study, we have constructed and phenotypically characterized deletion and conditional lon mutants in the model haloarchaeon Haloferax volcanii to elucidate the role of the unusual membrane-bound LonB protease in archaea. Hvlon could be deleted from the chromosome only when a copy of the wild type gene was provided in trans suggesting that Lon is essential for survival in this archaeon. Successful complementation of the lethal phenotype of ΔHvlon was attained by expression of the heterologous protease gene Nmlon from the haloalkaliphilic archaeon Natrialba magadii, meaning that the biological function of Lon is conserved in these organisms. Suboptimal cellular levels of Lon protein affected growth rate, cell shape, cell pigmentation, lipid composition and sensitivity to various antibiotics. The contents of bacterioruberins and some polar lipids were increased in the lon mutants suggesting that Lon is linked to maintenance of membrane lipid balance which likely affects cell viability in this archaeon. The phenotypes associated to a membrane-bound LonB protease mutant were examined for the first time providing insight on the relevance of this protease in archaeal physiology.


Assuntos
Proteínas Arqueais/genética , Haloferax volcanii/enzimologia , Lipídeos de Membrana/metabolismo , Peptídeo Hidrolases/genética , Antibacterianos/farmacologia , Proteínas Arqueais/metabolismo , Bacitracina/farmacologia , Sequência de Bases , Expressão Gênica , Regulação da Expressão Gênica em Archaea , Haloferax volcanii/efeitos dos fármacos , Lovastatina/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Novobiocina/farmacologia , Peptídeo Hidrolases/metabolismo , Pigmentação , Ligação Proteica , Puromicina/farmacologia
18.
Anal Bioanal Chem ; 406(1): 139-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24150283

RESUMO

The processing of particles, cells, and droplets for reactions, analyses, labeling, and coating is an important aspect of many microfluidic workflows. However, performing multi-step processes is typically a laborious and time-consuming endeavor. By exploiting the laminar nature of flow within microchannels, such procedures can benefit in terms of both speed and simplicity. This can be achieved either by manipulating the flow streams around the objects of interest, particularly for the localized perfusion of cells, or by manipulating the objects themselves within the streams via a range of forces. Here, we review the variety of methods that have been employed for performing such "multilaminar flow" procedures on particles, cells, and droplets.


Assuntos
Fenômenos Biomecânicos/fisiologia , Técnicas Analíticas Microfluídicas , Microfluídica/métodos , Reologia/métodos , Animais , Arabidopsis/citologia , Arabidopsis/fisiologia , Adesão Celular , Difusão , Células Eucarióticas/citologia , Células Eucarióticas/fisiologia , Humanos , Campos Magnéticos , Microfluídica/instrumentação , Pinças Ópticas , Tamanho da Partícula
19.
J Ind Microbiol Biotechnol ; 41(4): 607-17, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24519502

RESUMO

In the last two decades, a significant amount of work aimed at studying the ability of the white-rot fungus Coriolopsis rigida strain LPSC no. 232 to degrade lignin, sterols, as well as several hazardous pollutants like dyes and aliphatic and aromatic fractions of crude oil, including polycyclic aromatic hydrocarbons, has been performed. Additionally, C. rigida in association with arbuscular mycorrhizal fungi appears to enhance plant growth, albeit the physiological and molecular bases of this effect remain to be elucidated. C. rigida's ability to degrade lignin and lignin-related compounds and the capacity to transform the aromatic fraction of crude oil in the soil might be partially ascribed to its ligninolytic enzyme system. Two extracellular laccases are the only enzymatic components of its lignin-degrading system. We reviewed the most relevant findings regarding the activity and role of C. rigida LPSC no. 232 and its laccases and discussed the work that remains to be done in order to assess, more precisely, the potential use of this fungus and its extracellular enzymes as a model in several applied processes.


Assuntos
Coriolaceae/enzimologia , Lacase/metabolismo , Biodegradação Ambiental , Coriolaceae/classificação , Lacase/biossíntese , Lignina/metabolismo , Modelos Biológicos
20.
Bol Asoc Med P R ; 106(3): 36-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25470908

RESUMO

Follicular thyroid carcinoma is the second most common type of thyroid cancer, and its incidence has increased dramatically in recent years. Although it typically presents as a thyroid nodule, it can spread to distant sites via hematogenous dissemination. Bone metastasis is diagnosed clinically in 2%-13% of patients with differentiated thyroid cancer; nevertheless spinal cord compression complicating thyroid carcinoma is rare and only few cases has been reported in the literature. This case illustrates a strange case of a minimally invasive follicular carcinoma that showed an aggressive behavior, and thus the importance of considering metastatic thyroid carcinoma in the differential diagnosis of chronic back pain progressing to spinal cord compression carrying a severe morbidity.


Assuntos
Adenocarcinoma Folicular/diagnóstico , Dor nas Costas/etiologia , Compressão da Medula Espinal/etiologia , Neoplasias da Glândula Tireoide/diagnóstico , Adenocarcinoma Folicular/patologia , Dor Crônica/etiologia , Diagnóstico Diferencial , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias da Glândula Tireoide/patologia
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