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1.
Proc Natl Acad Sci U S A ; 119(28): e2200721119, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35867756

RESUMEN

Most retinoblastomas develop from maturing cone precursors in response to biallelic RB1 loss and are dependent on cone maturation-related signaling. Additionally, ∼2% lack RB1 mutations but have MYCN amplification (MYCNA), N-Myc protein overexpression, and more rapid and invasive growth, yet the MYCNA retinoblastoma cell of origin and basis for its responses to deregulated N-Myc are unknown. Here, using explanted cultured retinae, we show that ectopic N-Myc induces cell cycle entry in cells expressing markers of several retinal types yet induces continuous proliferation and tumorigenesis only in cone precursors. Unlike the response to RB1 loss, both immature cone arrestin-negative (ARR3-) and maturing ARR3+ cone precursors proliferate, and maturing cone precursors rapidly dedifferentiate, losing ARR3 as well as L/M-opsin expression. N-Myc-overexpressing retinal cells also lose cell lineage constraints, occasionally coexpressing the cone-specific RXRγ with the rod-specific NRL or amacrine-specific AP2α and widely coexpressing RXRγ with the progenitor and Müller cell-specific SOX9 and retinal ganglion cell-specific BRN3 and GAP43. Mechanistically, N-Myc induced Cyclin D2 and CDK4 overexpression, pRB phosphorylation, and SOX9-dependent proliferation without a retinoma-like stage that characterizes pRB-deficient retinoblastoma, despite continuous p16INK4A expression. Orthotopic xenografts of N-Myc-overexpressing retinal cells formed tumors with retinal cell marker expression similar to those in MYCN-transduced retinae and MYCNA retinoblastomas in patients. These findings demonstrate the MYCNA retinoblastoma origin from immature and lineage-deconstrained cone precursors, reveal their opportunistic use of an undifferentiated retinal progenitor cell feature, and illustrate that different cancer-initiating mutations cooperate with distinct developmental stage-specific cell signaling circuitries to drive retinoblastoma tumorigenesis.


Asunto(s)
Carcinogénesis , Proteína Proto-Oncogénica N-Myc , Células Fotorreceptoras Retinianas Conos , Neoplasias de la Retina , Retinoblastoma , Carcinogénesis/genética , Ciclo Celular , Humanos , Proteína Proto-Oncogénica N-Myc/genética , Proteína Proto-Oncogénica N-Myc/metabolismo , Células Fotorreceptoras Retinianas Conos/metabolismo , Células Fotorreceptoras Retinianas Conos/patología , Neoplasias de la Retina/metabolismo , Neoplasias de la Retina/patología , Retinoblastoma/metabolismo , Retinoblastoma/patología
2.
Br J Cancer ; 131(1): 90-100, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38806726

RESUMEN

BACKGROUND: Intrinsic and extrinsic factors in the tumour microenvironment (TME) contribute to therapeutic resistance. Here we demonstrate that transforming growth factor (TGF)-ß1 produced in the TME increased drug resistance of neuroblastoma (NB) cells. METHODS: Human NB cell lines were tested in vitro for their sensitivity to Doxorubicin (DOX) and Etoposide (ETOP) in the presence of tumour-associated macrophages (TAM) and mesenchymal stromal cells/cancer-associated fibroblasts (MSC/CAF). These experiments were validated in xenotransplanted and primary tumour samples. RESULTS: Drug resistance was associated with an increased expression of efflux transporter and anti-apoptotic proteins. Upregulation was dependent on activation of nuclear factor (NF)-κB by TGF-ß-activated kinase (TAK1) and SMAD2. Resistance was reversed upon pharmacologic and genetic inhibitions of NF-κB, and TAK1/SMAD2. Interleukin-6, leukaemia inhibitory factor and oncostatin M were upregulated by this TGF-ß/TAK1/NF-κB/SMAD2 signalling pathway contributing to drug resistance via an autocrine loop activating STAT3. An analysis of xenotransplanted NB tumours revealed an increased presence of phospho (p)-NF-κB in tumours co-injected with MSC/CAF and TAM, and these tumours failed to respond to Etoposide but responded if treated with a TGF-ßR1/ALK5 inhibitor. Nuclear p-NF-κB was increased in patient-derived tumours rich in TME cells. CONCLUSIONS: The data provides a novel insight into a targetable mechanism of environment-mediated drug resistance.


Asunto(s)
Doxorrubicina , Resistencia a Antineoplásicos , FN-kappa B , Neuroblastoma , Factor de Crecimiento Transformador beta1 , Microambiente Tumoral , Humanos , Microambiente Tumoral/efectos de los fármacos , Neuroblastoma/metabolismo , Neuroblastoma/patología , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/genética , FN-kappa B/metabolismo , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Línea Celular Tumoral , Doxorrubicina/farmacología , Ratones , Etopósido/farmacología , Transducción de Señal/efectos de los fármacos , Quinasas Quinasa Quinasa PAM/metabolismo , Proteína Smad2/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/efectos de los fármacos , Fibroblastos Asociados al Cáncer/patología , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Development ; 148(23)2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34738615

RESUMEN

The development of the first synapse of the visual system between photoreceptors and bipolar cells in the outer plexiform layer (OPL) of the human retina is crucial for visual processing but poorly understood. By studying the maturation state and spatial organization of photoreceptors, depolarizing bipolar cells and horizontal cells in the human fetal retina, we establish a pseudo-temporal staging system for OPL development that we term OPL-Stages 0 to 4. This was validated through quantification of increasingly precise subcellular localization of bassoon to the OPL with each stage (P<0.0001). By applying these OPL staging criteria to human retinal organoids (HROs) derived from human embryonic and induced pluripotent stem cells, we observed comparable maturation from OPL-Stage 0 at day 100 in culture up to OPL-Stage 3 by day 160. Quantification of presynaptic protein localization confirmed progression from OPL-Stage 0 to 3 (P<0.0001). Overall, this study defines stages of human OPL development through mid-gestation and establishes HROs as a model system that recapitulates key aspects of human photoreceptor-bipolar cell synaptogenesis in vitro.


Asunto(s)
Células Madre Embrionarias Humanas/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Organoides/metabolismo , Retina/metabolismo , Línea Celular , Células Madre Embrionarias Humanas/citología , Humanos , Células Madre Pluripotentes Inducidas/citología , Organoides/citología , Retina/citología
4.
Exp Eye Res ; 244: 109947, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38815793

RESUMEN

The non-canonical Wnt pathway is an evolutionarily conserved pathway essential for tissue patterning and development across species and tissues. In mammals, this pathway plays a role in neuronal migration, dendritogenesis, axon growth, and synapse formation. However, its role in development and synaptogenesis of the human retina remains less established. In order to address this knowledge gap, we analyzed publicly available single-cell RNA sequencing (scRNAseq) datasets for mouse retina, human retina, and human retinal organoids over multiple developmental time points during outer retinal maturation. We identified ligands, receptors, and mediator genes with a putative role in retinal development, including those with novel or species-specific expression, and validated this expression using fluorescence in situ hybridization (FISH). By quantifying outer nuclear layer (ONL) versus inner nuclear layer (INL) expression, we provide evidence for the differential expression of certain non-canonical Wnt signaling components in the developing mouse and human retina during outer plexiform layer (OPL) development. Importantly, we identified distinct expression patterns of mouse and human FZD3 and WNT10A, as well as previously undescribed expression, such as for mouse Wnt2b in Chat+ starburst amacrine cells. Human retinal organoids largely recapitulated the human non-canonical Wnt pathway expression. Together, this work provides the basis for further study of non-canonical Wnt signaling in mouse and human retinal development and synaptogenesis.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Retina , Vía de Señalización Wnt , Animales , Ratones , Humanos , Retina/metabolismo , Retina/crecimiento & desarrollo , Retina/embriología , Vía de Señalización Wnt/fisiología , Hibridación Fluorescente in Situ , Organoides/metabolismo , Ratones Endogámicos C57BL
5.
Med Vet Entomol ; 37(3): 499-510, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36896712

RESUMEN

To identify the questing tick populations in urban and suburban areas from the city of Lugo (NW Spain), ticks were collected monthly by flagging. The presence of Borrelia spp., Rickettsia spp. and Anaplasma phagocytophilum also was determined by polymerase chain reaction (PCR) and sequence analysis. Overall, 342 questing ticks were collected; the tick abundance was higher in suburban (95.9%) than in urban areas (4.1%). Ixodes frontalis was the most abundant (86.5%); 88.5% were larvae, 11.1% nymphs and 0.3% adults. All development stages of I. ricinus (7.3%) and adults of Rhipicephalus sanguineus sensu lato (5.8%) and Dermacentor reticulatus (0.3%) were found. Rickettsia spp. (31.9%) was more prevalent than Borrelia spp. (2.7%); no ticks were positive to A. phagocytophilum. Six Rickettsia species were identified (R. slovaca, R. monacensis, R. massiliae, R. raoultii, R. sibirica subsp. mongolitimonae and R. aeschielmanii); Candidatus Rickettsia rioja and two novel Rickettsia species also were detected. In addition, Borrelia turdi (1.8%) and B. valaisiana (0.9%) were identified in Ixodes ticks. This is the first report of R. slovaca in R. sanguineus s.l. and of R. monacensis, R. raoultii, R. slovaca, R. sibirica subsp. mongolitimonae and Ca. R. rioja in I. frontalis. Since most of the pathogens detected are zoonotic, their presence in these areas may have implications for public health.


Asunto(s)
Borrelia , Ixodes , Rickettsia , Animales , España , Ciudades
6.
Trop Anim Health Prod ; 56(1): 20, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110670

RESUMEN

Argentina is a small player in the global pork market, contributing only 0.7% of the total production. With increasing global demand for meat, there is an opportunity for countries with an agricultural profile to grow their pork production. However, there is a need to understand the current state of the pork production sector in all aspects to inform decision-making. The aim of this study was to genetically characterize pig herds from different production strata in the primary region for pork production in the country. For this purpose, phylogenetic and genetic variability analyses were performed using the mitochondrial control region marker (n=95 pig samples). Moreover, genotyping of ryr1 and PRKAG3 genes (n=108 pig samples) were performed to evaluate the frequency of deleterious alleles for meat quality traits in the region. The results showed high levels of genetic variability in the pig herds (Hd= 0.840 ± 0.031 and π= 0.010 ± 0.001), with a creole sow and Iberian lineage standing out in the phylogeny. The genotyping of the ryr1 marker revealed the presence of the deleterious t allele in all analyzed strata. However, the RN-allele of the PRKAG3 gene was detected only in the two lower strata. This study represents the first analysis of the phylogenetic relationships among domestic pigs from Argentina and provides an initial assessment of genetic variability in the region. Additionally, the results present, for the first time, the frequency of deleterious alleles for pig production in the productive core area, demonstrating their prevalence.


Asunto(s)
Canal Liberador de Calcio Receptor de Rianodina , Sus scrofa , Porcinos/genética , Animales , Femenino , Sus scrofa/genética , Canal Liberador de Calcio Receptor de Rianodina/genética , Argentina , Filogenia , Carne/análisis
7.
Langenbecks Arch Surg ; 407(8): 3631-3642, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36251077

RESUMEN

PURPOSE: Familial papillary thyroid microcarcinoma (FPTMC) can present a more aggressive behavior than the sporadic microcarcinoma. However, few studies have analyzed this situation. The objective is to analyze the recurrence rate of FPTMC and the prognostic factors which determine that recurrence in Spain. METHODS: Spanish multicenter longitudinal analytical observational study was conducted. Patients with FPTMC received treatment with curative intent and presented cure criteria 6 months after treatment. Recurrence rate and disease-free survival (DFS) were analyzed. Two groups were analyzed: group A (no tumor recurrence) vs. group B (tumor recurrence). RESULTS: Ninety-four patients were analyzed. During a mean follow-up of 73.3 ± 59.3 months, 13 recurrences of FPTMC (13.83%) were detected and mean DFS was 207.9 ± 11.5 months. There were multifocality in 56%, bilateral thyroid involvement in 30%, and vascular invasion in 7.5%; that is to say, they are tumors with histological factors of poor prognosis in a high percentage of cases. The main risk factors for recurrence obtained in the multivariate analysis were the tumor size (OR: 2.574, 95% CI 1.210-5.473; p = 0.014) and the assessment of the risk of recurrence of the American Thyroid Association (ATA), both intermediate risk versus low risk (OR: 125, 95% CI 10.638-1000; p < 0.001) and high risk versus low risk (OR: 45.454, 95% CI 5.405-333.333; p < 0.001). CONCLUSION: FPTMC has a recurrence rate higher than sporadic cases. Poor prognosis is mainly associated with the tumor size and the risk of recurrence of the ATA.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/cirugía , Supervivencia sin Enfermedad , Pronóstico , Estudios Retrospectivos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología
8.
Neurobiol Learn Mem ; 179: 107409, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33609738

RESUMEN

Ghrelin (Gr) is an orexigenic peptide that acts via its specific receptor, GHSR-1a distributed throughout the brain, being mainly enriched in pituitary, cortex and hippocampus (Hp) modulating a variety of brain functions. Behavioral, electrophysiological and biochemical evidence indicated that Gr modulates the excitability and the synaptic plasticity in Hp. The present experiments were designed in order to extend the knowledge about the Gr effect upon structural synaptic plasticity since morphological and quantitative changes in spine density after Gr administration were analyzed "in vitro" and "in vivo". The results show that Gr administered to hippocampal cultures or stereotactically injected in vivo to Thy-1 mice increases the density of dendritic spines (DS) being the mushroom type highly increased in secondary and tertiary extensions. Spines classified as thin type were increased particularly in primary extensions. Furthermore, we show that Gr enhances selectively the expression of BDNF-mRNA species.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/efectos de los fármacos , Ghrelina/farmacología , Hipocampo/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Células Piramidales/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/patología , Hipocampo/citología , Hipocampo/metabolismo , Microscopía Confocal , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Células Piramidales/metabolismo , Células Piramidales/patología , ARN Mensajero/metabolismo , Ratas
9.
Med Vet Entomol ; 35(1): 51-58, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32757238

RESUMEN

Anaplasma phagocytophilum and some piroplasm species are pathogens mainly transmitted by Ixodes ricinus. Considering that this tick species is predominant in north-western Spain, individual specimens (652 nymphs, 202 females and 202 males) and 23 larval pools were processed to determine the prevalence of these pathogens in questing I. ricinus from that region. Additionally, Dermacentor marginatus, Dermacentor reticulatus, Ixodes frontalis and Ixodes acuminatus were individually analysed. The groESL operon as well as the 16S rRNA and msp2 genes of Anaplasma were analysed. Similarly, piroplasms were identified at the 18S rRNA gene and the ITS1 of Babesia spp. and Theileria spp. Babesia venatorum (1.5%), A. phagocytophilum (0.7%), Babesia microti (0.3%) and Theileria sp. OT3 (0.2%) were detected in I. ricinus. A single I. frontalis (8.3%) tested positive to A. phagocytophilum. Although a low percentage of I. ricinus were infected with A. phagocytophilum and piroplasms, a potentially human pathogenic variant of A. phagocytophilum was detected, and both Babesia species found were zoonotic. Since the vector of Theileria sp. OT3 remains unknown, further investigations are needed to unravel the role of I. ricinus in the transmission of this piroplasm.


Asunto(s)
Anaplasma phagocytophilum/aislamiento & purificación , Babesia/aislamiento & purificación , Ixodidae/microbiología , Ixodidae/parasitología , Theileria/aislamiento & purificación , Animales , Proteínas de la Membrana Bacteriana Externa/análisis , Femenino , Genoma Bacteriano , Ixodidae/crecimiento & desarrollo , Larva/microbiología , Larva/parasitología , Masculino , Ninfa/microbiología , Ninfa/parasitología , Operón , ARN Bacteriano/análisis , ARN Protozoario/análisis , ARN Ribosómico 16S/análisis , ARN Ribosómico 18S/análisis , España
10.
J Intellect Disabil Res ; 65(9): 831-848, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34196436

RESUMEN

BACKGROUND: Individuals with developmental disabilities (DD) often have severe impairments and maladaptive behaviours that make it difficult to reliably assess their cognitive abilities. Given these challenges, the Rapid Assessment of Developmental Disabilities, Second Edition (RADD-2), was designed to measure general cognitive ability in this population. The purpose of this study is to demonstrate the battery's psychometric properties when used with individuals with DD who have challenging behavioural and psychiatric conditions and for those who have limited verbal skills. METHOD: The cognitive and adaptive behaviour skills of 193 children and adults with DD and considerable medical, behavioural and/or psychiatric problems were evaluated using the first and second editions of the RADD, Kaufmann Brief Intelligence Test - 2nd Edition, and Scales of Independent Behaviour - Revised Edition. Medication side effects and challenging behaviours were assessed using the Aberrant Behaviour Checklist. RESULTS: There were no floor or ceiling effects on the RADD-2. Both the nonverbal index and total scores had strong concurrent validity with other abbreviated tests of intellectual ability and good discriminant validity from measures of adaptive behaviour and medication side effects. RADD-2 scores also had strong criterion validity as they successfully differentiated between all levels of intellectual functioning. Age and sex did not differentially affect RADD-2 performance, and the co-occurrence of psychiatric conditions did not negatively affect performance. The only medical condition associated with lower RADD-2 performance was epilepsy. CONCLUSIONS: The RADD-2 can quantify the differential cognitive abilities of individuals with DD, even for those with minimal communication skills, challenging behaviours or severe medication side effects that can typically complicate assessment. This brief cognitive battery can be used to measure changes due to interventions, on the one hand, and progression of neurological disease, on the other.


Asunto(s)
Adaptación Psicológica , Discapacidades del Desarrollo , Adulto , Niño , Cognición , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/diagnóstico , Humanos , Psicometría
11.
Neuroimage ; 210: 116543, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31940475

RESUMEN

In the last few years the involvement of the medial prefrontal cortex (mPFC) in memory processing has received increased attention. It has been shown to be centrally involved when we use prior knowledge (schemas) to improve learning of related material. With the mPFC also being one of the core hubs of the default mode network (DMN) and the DMN's role in memory retrieval, we decided to investigate whether the mPFC in a schema paradigm acts independent of the DMN. We tested this with data from a cross-sectional developmental study with a schema paradigm. During retrieval of schema items, the mPFC decoupled from the DMN with the degree of decoupling predicting memory performance. This finding suggests that a demand specific reconfiguration of the DMN supports schema memory. Additionally, we found that in the control condition, which relied on episodic memory, activity in the parahippocampal gyrus was positively related to memory performance. We interpret these results as a demand specific network reconfiguration of the DMN: a decoupling of the mPFC to support schema memory and a decoupling of the parahippocampal gyrus facilitating episodic memory.


Asunto(s)
Aprendizaje por Asociación , Asociación , Conectoma , Red en Modo Predeterminado/fisiología , Memoria Episódica , Recuerdo Mental/fisiología , Red Nerviosa/fisiología , Giro Parahipocampal/fisiología , Corteza Prefrontal/fisiología , Adolescente , Adulto , Niño , Conectoma/métodos , Red en Modo Predeterminado/diagnóstico por imagen , Femenino , Humanos , Individualidad , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Giro Parahipocampal/diagnóstico por imagen , Reconocimiento Visual de Modelos/fisiología , Corteza Prefrontal/diagnóstico por imagen , Percepción Espacial/fisiología , Adulto Joven
12.
Insect Mol Biol ; 29(5): 431-443, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32484986

RESUMEN

Insect cuticle hydrocarbons are involved primarily in waterproofing the cuticle, but also participate in chemical communication and regulate the penetration of insecticides and microorganisms. The last step in insect hydrocarbon biosynthesis is carried out by an insect-specific cytochrome P450 of the 4G subfamily (CYP4G). Two genes (CYP4G106 and CYP4G107) have been reported in the triatomines Rhodnius prolixus and Triatoma infestans. In this work, their molecular and functional characterization is carried out in R. prolixus, and their relevance to insect survival is assessed. Both genes are expressed almost exclusively in the integument and have an expression pattern dependent on the developmental stage and feeding status. CYP4G106 silencing diminished significantly the straight-chain hydrocarbon production while a significant reduction - mostly of methyl-branched chain hydrocarbons - was observed after CYP4G107 silencing. Molecular docking analyses using different aldehydes as hydrocarbon precursors predicted a better fit of straight-chain aldehydes with CYP4G106 and methyl-branched aldehydes with CYP4G107. Survival bioassays exposing the silenced insects to desiccation stress showed that CYP4G107 is determinant for the waterproofing properties of the R. prolixus cuticle. This is the first report on the in vivo specificity of two CYP4Gs to make mostly straight or methyl-branched hydrocarbons, and also on their differential contribution to insect desiccation.


Asunto(s)
Familia 4 del Citocromo P450/genética , Desecación , Hidrocarburos/metabolismo , Proteínas de Insectos/genética , Rhodnius/fisiología , Animales , Familia 4 del Citocromo P450/metabolismo , Proteínas de Insectos/metabolismo , Ninfa/genética , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Rhodnius/genética , Rhodnius/crecimiento & desarrollo
13.
Med Vet Entomol ; 34(1): 44-48, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31444796

RESUMEN

The host switching of Hypoderma actaeon (Diptera: Oestridae), a specific parasite of red deer (Cervus elaphus), towards roe deer (Capreolus capreolus) has been recently reported in Spain. To provide information about the temporal and spatial spreading of H. actaeon infection in roe deer, 244 serum samples from animals hunted in Spain between 2013 and 2018 were analysed by an indirect enzyme-linked immunosorbent assay. The overall seropositivity was 13.9%. Seropositivity was higher in continental (27.7%) and mountainous (12%) areas from central Spain, followed by southern-Mediterranean (11.2%) and northern-oceanic regions (3.5%). Differences were significant between central-continental and northern-oceanic regions (P = 0.003). No differences were found according to the sex and age of roe deer (P > 0.05). In 2013, all seropositive animals were concentrated in two distant areas in central and southern Spain, suggesting that the host switch could have occurred independently in both regions. Changes in the pattern of distribution of red deer and roe deer could have favoured the spreading of this myiasis towards roe deer, indicating that roe deer may become infested by H. actaeon in areas where both cervids coexist at high densities.


Asunto(s)
Ciervos , Dípteros/fisiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Hipodermosis/veterinaria , Animales , Dípteros/crecimiento & desarrollo , Femenino , Hipodermosis/epidemiología , Larva/fisiología , Masculino , Estudios Seroepidemiológicos , España/epidemiología
14.
Nat Mater ; 17(1): 28-35, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29180774

RESUMEN

Most of the magnetic devices in advanced electronics rely on the exchange bias effect, a magnetic interaction that couples a ferromagnetic and an antiferromagnetic material, resulting in a unidirectional displacement of the ferromagnetic hysteresis loop by an amount called the 'exchange bias field'. Setting and optimizing exchange bias involves cooling through the Néel temperature of the antiferromagnetic material in the presence of a magnetic field. Here we demonstrate an alternative process for the generation of exchange bias. In IrMn/FeCo bilayers, a structural phase transition in the IrMn layer develops at room temperature, exchange biasing the FeCo layer as it propagates. Once the process is completed, the IrMn layer contains very large single-crystal grains, with a large density of structural defects within each grain, which are promoted by the FeCo layer. The magnetic characterization indicates that these structural defects in the antiferromagnetic layer are behind the resulting large value of the exchange bias field and its good thermal stability. This mechanism for establishing the exchange bias in such a system can contribute towards the clarification of fundamental aspects of this exchange interaction.

15.
Expert Rev Proteomics ; 16(7): 583-591, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31195841

RESUMEN

Introduction: Hypertension is a multifactorial disease that has, thus far, proven to be a difficult target for pharmacological intervention. The application of proteomic strategies may help to identify new biomarkers for the early diagnosis and prompt treatment of hypertension, in order to control blood pressure and prevent organ damage. Areas covered: Advances in proteomics have led to the discovery of new biomarkers to help track the pathophysiological processes implicated in hypertension. These findings not only help to better understand the nature of the disease, but will also contribute to the clinical needs for a timely diagnosis and more precise treatment. In this review, we provide an overview of new biomarkers identified in hypertension through the application of proteomic techniques, and we also discuss the difficulties and challenges in identifying biomarkers in this clinical setting. We performed a literature search in PubMed with the key words 'hypertension' and 'proteomics', and focused specifically on the most recent literature on the utility of proteomics in hypertension research. Expert opinion: There have been several promising biomarkers of hypertension identified by proteomics, but too few have been introduced to the clinic. Thus, further investigations in larger cohorts are necessary to test the feasibility of this strategy for patients. Also, this emerging field would profit from more collaboration between clinicians and researchers.


Asunto(s)
Biomarcadores/metabolismo , Hipertensión/metabolismo , Proteómica/métodos , Humanos , Medicina de Precisión/métodos
16.
Insect Mol Biol ; 28(6): 850-861, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31125161

RESUMEN

Fatty acid synthase is a multifunctional enzyme involved in the formation of fatty acids. Despite the role of fatty acids in cell signalling and energy metabolism, and as precursors to pheromones and hydrocarbons that waterproof the cuticle, the insect fatty acid synthases have been scarcely studied. Here we perform the molecular characterization of three fatty acid synthase genes (fatty acid synthase RPRC000123, RPRC000269 and RPRC002909) in the Chagas disease vector, Rhodnius prolixus. Gene expression screening by reverse transcription quantitative PCR showed that RPRC000123 and RPRC002909 are expressed almost exclusively in the integument tissue whilst RPRC000269 is mostly expressed in the fat body and also in several body organs. Phylogenetic analysis, together with gene expression results, showed that RPRC000269, RPRC002909 and RPRC000123 are orthologues of Drosophila melanogaster fatty acid synthase 1 (FASN1), FASN2 and FASN3 genes, respectively. After RNA interference-mediated knockdown of RPRC000123, insects died immediately after moulting to the next developmental stage. However, mortality was prevented by placing the insects under saturated humidity conditions, suggesting that dehydration might play a role in the insects' death. Lipid analyses in RPRC000123-silenced insects showed reduced amounts of integument fatty acids and methyl-branched hydrocarbons, compared to controls. These data support an important role for FASN3 in the biosynthesis of the precursors to hydrocarbons that waterproof the insect cuticle.


Asunto(s)
Ácido Graso Sintasas/genética , Proteínas de Insectos/genética , Agua/metabolismo , Animales , Ácido Graso Sintasas/metabolismo , Proteínas de Insectos/metabolismo , Integumento Común/fisiología , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Filogenia , Rhodnius , Pérdida Insensible de Agua
17.
Med Vet Entomol ; 33(3): 427-430, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30730054

RESUMEN

Ixodes ricinus, comprising the predominant tick species in Europe, can transmit important human pathogens, including Borreliella spp., the causal agent of Lyme borreliosis. One hundred and seventy five roe deer hunted in two areas (plateau and mountain) of Galicia (northwest Spain) were examined for the presence of ticks; all roe deer were infested by I. ricinus. Nymphs (n = 1000), males (n = 1449) and females (n = 1000) of I. ricinus were analysed in pools of up to 10 ticks to detect both Borreliella and Borrelia DNA. The average number of I. ricinus per roe deer was similar in both areas, regardless of the life stage; although the percentage of Borreliella and Borrelia positive pools was higher in ticks collected from roe deer hunted in the plateau area, no significant differences were detected. Sequence analysis at the flagellin gene allowed the identification of four Borreliella species (Borreliella afzelii, Borreliella garinii, Borreliella lusitaniae and Borreliella valaisiana) and Borrelia miyamotoi in adult males; only B. valaisiana and B. miyamotoi were detected in nymphs and all females were negative. All Borreliella and Borrelia species found in roe deer were previously identified in questing I. ricinus collected in the same study area, although the prevalence was lower in the present study. The analysis of male I. ricinus ticks collected from roe deer gives a good estimation of Borreliella diversity in questing ticks.


Asunto(s)
Ciervos/parasitología , Ixodes/microbiología , Spirochaetaceae/aislamiento & purificación , Animales , Borrelia/aislamiento & purificación , Femenino , Especificidad del Huésped , Interacciones Huésped-Parásitos , Ixodes/crecimiento & desarrollo , Masculino , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , España
19.
J Esthet Restor Dent ; 31(5): 493-499, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31192538

RESUMEN

OBJECTIVES: This split-mouth, double-blind, randomized clinical trial evaluated the 1-year bleaching efficacy produced by two hydrogen peroxide gels with different pHs. MATERIALS AND METHODS: Twenty-eight patients were divided into two groups corresponding to two different products: Pola Office (pH = 2.0/SDI) and Pola Office Plus (pH = 7.0/SDI). The treatment was assessed during and after the bleaching procedure up to 12 months post-treatment. The assessment consisted of two bleaching scales shade guide units (ΔSGU) and spectrophotometric device (ΔE, ΔE00, and Whiteness Index) of both maxillary quadrants. Results for ΔSGUs in both scales and ΔE00 and Whiteness Index were compared using Mann Whitney test and ΔE measurements through the t-Student test for paired samples in each evaluation time. The color rebound (1- vs 12-month postbleaching data) was evaluated with Wilcoxon test (alpha = .05). RESULTS: During the different times of evaluation, the color variation was similar for both products (P > .05), both for subjective (ΔSGUs) and objective assessments (ΔE, ΔE00, and Whiteness Index). Also, both products showed a slight rebound after 12-month postbleaching (P > .05). CONCLUSIONS: Concerning the stability of color, in-office dental whitening with two hydrogen peroxide gels of different pHs produced similar results, with no significant of regression, for 12 months postwhitening. CLINICAL SIGNIFICANCE: Bleaching using a neutral (pH = 7.0) in-office gel demonstrated similar stability and rebound effect than an acidic one (pH = 2.0).


Asunto(s)
Sensibilidad de la Dentina , Blanqueadores Dentales , Blanqueamiento de Dientes , Color , Método Doble Ciego , Geles , Humanos , Peróxido de Hidrógeno , Resultado del Tratamiento
20.
N Z Vet J ; 67(5): 249-256, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31131738

RESUMEN

Aims: To examine the association between the detection of Ureaplasma diversum in vaginal swabs from dairy cows in north western Spain with the diagnosis of granular vulvovaginitis (GVV) and reproductive performance, and the association with subclinical endometritis (SE) in slaughterhouse material. The presence of this microorganism in cases of abortion was also investigated. Methods: From 106 dairy farms in the province of Lugo, 40 herds were randomly selected. Vaginal swabs were obtained from 10 randomly selected cows per farm, then pooled for analysis to detect the presence of U. diversum by quantitative real-time PCR (qPCR). In five of these herds samples from the 10 animals were individually tested for U. diversum, and the presence of GVV lesions and their reproductive efficiency (number of inseminations to achieve pregnancy over two subsequent pregnancies) were determined. Vaginal swabs from uteri of cattle obtained at a slaughterhouse (n = 100) were tested for U. diversum and the presence of SE, defined as >5% polymorphonuclear cells in cytobrush smears, was determined. Sixteen farms with abortion problems submitted samples for culture and PCR testing including for U. diversum. Results: Of the 40 herds, 39 (98%) tested positive for U. diversum. On the five farms, 25/50 (50%) cows tested positive for U. diversum, and more cows with GGV-lesions (16/25; 64%) tested positive than cows without lesions (9/25; 36%) (p = 0.047). There were more cows with poor reproductive efficacy that tested positive (8/11; 57%) than tested negative (3/17; 18%) for U. diversum (p = 0.029). Of the 100 uteri, five tested positive for U. diversum and there were more uteri with SE that tested positive (3/19; 16%) than uteri without SE (2/81; 2%) (p = 0.036). U. diversum was also diagnosed in 4/16 farms with abortion problems and liver appeared to be the best tissue for detecting U. diversum DNA in the fetuses analysed. Conclusions and Clinical Relevance: Infection with U. diversum was present in most of herds investigated and it was statistically associated with GVV, SE and poor reproductive performance. It was also detected in abortions and the liver may also be an additional tissue to be considered in the diagnosis of U. diversum abortion by PCR. The possible association with different diseases in the same area suggests that different presentations should be considered when studying the implications of U. diversum on the reproductive diseases of cattle.


Asunto(s)
Aborto Veterinario/microbiología , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Endometritis/veterinaria , Infecciones por Ureaplasma/veterinaria , Vulvovaginitis/veterinaria , Aborto Veterinario/epidemiología , Crianza de Animales Domésticos , Animales , Bovinos , Industria Lechera , Endometritis/epidemiología , Endometritis/microbiología , Femenino , Modelos Logísticos , Reacción en Cadena de la Polimerasa , Embarazo , España/epidemiología , Ureaplasma/aislamiento & purificación , Infecciones por Ureaplasma/epidemiología , Frotis Vaginal/veterinaria , Vulvovaginitis/epidemiología , Vulvovaginitis/microbiología
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