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1.
Med Oral Patol Oral Cir Bucal ; 29(4): e498-e508, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38288851

RESUMEN

BACKGROUND: The aim was to evaluate the frequency, clinicopathological features, and HPV status of oropharyngeal squamous cell carcinoma (OP-SCC) and benign HPV-related epithelial lesions of the oropharynx over the last 25 years. Moreover, a literature review was performed to investigate HPV frequency in OP-SCC samples diagnosed in Brazilian Centers. MATERIAL AND METHODS: A cross-sectional study analyzed OP-SCC, squamous papilloma, verruca vulgaris, and condyloma accuminatum, diagnosed from 1997 to 2021. HPV status of OP-SCC was determined by immunohistochemistry and "in situ" hybridization. Bivariate statistics were performed (p≤0.05). For the literature review, MEDLINE/PubMed, Web of Science, EMBASE, and Scopus were searched. Two independent reviewers assessed the studies for eligibility. RESULTS: Cross-sectional: 211 OP-SCC (63.0%) and 124 benign lesions (37.0%) were included. OP-SCC frequency increased gradually over time, whereas benign lesions had steady trends. OP-SCC affected more males (n= 171; 81.0%), though the relative frequency in females rose over time. Smoking (n= 127; 60.2%) was common in OP-SCC. Nineteen OP-SCC (13.0%) were positive for HPV. HPV-positive and HPV-negative tumors had similar clinicopathological features (p>0.05). Benign lesions predominated in middle-aged (n= 32; 26.7%) women (n= 71; 57.3%), in the soft palate (n=101; 81.5%). LITERATURE REVIEW: 32 studies were included, and in 60% of them, HPV frequency in OP-SCC was less than 25%. CONCLUSIONS: OP-SCC prevalence has been increasing, and it was mostly associated with smoking and alcohol rather than with HPV infection in Brazil. Benign lesions had a stationary frequency over the evaluated period.


Asunto(s)
Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Estudios Transversales , Brasil/epidemiología , Neoplasias Orofaríngeas/virología , Neoplasias Orofaríngeas/epidemiología , Neoplasias Orofaríngeas/patología , Infecciones por Papillomavirus/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Carcinoma de Células Escamosas/virología , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Adulto , Anciano , Factores de Tiempo , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Carcinoma de Células Escamosas de Cabeza y Cuello/epidemiología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología
2.
Med Oral Patol Oral Cir Bucal ; 28(6): e512-e518, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37823302

RESUMEN

BACKGROUND: Oral Lichen Planus is a potential malignant disorder and shares clinical and histopathological features with other similar lesions. ALDH1 is a specific biomarker for stem cells identification, however its role in stromal cells of immune inflammatory infiltrate has not been explored. The aim of this study was to investigate the ALDH1 immunoexpression in epithelial and stromal cells of Oral Lichen Planus and other lesions with lichenoid inflammatory infiltrate. MATERIAL AND METHODS: 64 samples of Oral Lichen Planus, Oral Lichenoid Lesions, Oral Leukoplakia and Unspecific Chronic Inflammation were included. ALDH1 was evaluated in both epithelium and stromal cells. ALDH1+ cells ≥ 5% were considered positive in epithelium. Stromal cells were evaluated semi quantitatively. Fields were ranked in scores, according to criteria: 1 (0 to 10%); 2 (11 to 50%) and 3 (>50%). The mean value of the sum of the fields was the final score. Statistical differences among groups were investigated, considering p < 0.05. RESULTS: ALDH1 expression in epithelium was low in all groups without difference among them. ALDH1+ cells in the lamina propria were higher for Lichen Planus [2.0], followed by Leukoplakia [1.3], Lichenoid lesions [1.2] and control [1.1] (p<0.05). CONCLUSIONS: ALDH1 immunoexpression in epithelium of lichenoid potential malignant disorders did not show a contributory tool, however ALDH1 in stromal cells of lichen planus might be involved in the complex process of immune regulation associated with the pathogenesis of this disease.


Asunto(s)
Liquen Plano Oral , Erupciones Liquenoides , Humanos , Liquen Plano Oral/patología , Erupciones Liquenoides/patología , Epitelio/patología , Células del Estroma/patología
3.
Med Oral Patol Oral Cir Bucal ; 28(6): e588-e595, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37471299

RESUMEN

BACKGROUND: With the COVID-19 pandemic, there was a need to adopt online teaching methods in a generalized and sudden way, a situation that led to unprecedented changes in the routine of post-graduate students and research development. This study aimed to analyze the evaluation of remote teaching by graduates of master's degrees and advisors in master's programs in the Oral Pathology and Oral Medicine who needed to adapt to a remote teaching methodology in the pandemic. MATERIAL AND METHODS: This quantitative study evaluated the remote teaching in the perception of master's graduates and advisors from postgraduate programs in Oral Pathology and Oral Medicine. Data were collected through an online Google forms® questionnaire. RESULTS: Participated in the study 14 master graduates and 14 master's advisors. Master graduates evaluated that the professors had a good performance (p=0.001), that the duration of the classes was adequate (p=0.015), that the interaction with professors was satisfactory (p=0.007), that they had good interaction with the advisor (p=0.001), that they were satisfied with the remote guidance process (p=0.038) and that face-to-face practical activities were missed (p=0.002). Master's advisors reported satisfaction with remote teaching, good adaptation (p=0.018) and motivation for remote teaching (p=0.016), they evaluated that students were cooperative in activities (p=0.019) and that face-to-face practical activities were missed (p=0.002). CONCLUSIONS: Despite the difficulties, remote teaching proved to be an effective alternative to face-to-face teaching.


Asunto(s)
COVID-19 , Pandemias , Humanos , Brasil , Patología Bucal , Encuestas y Cuestionarios
4.
J Biol Inorg Chem ; 25(8): 1117-1128, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33104887

RESUMEN

Invasive fungal infections (IFIs) are life threatening and existing antifungal drugs are not completely effective due to undesirable side effects and resistance emergence. Azoles are often the treatment of choice for IFIs and growing evidence suggests that copper can act synergistically with these drugs. In this work, we designed a compound bringing together azole and copper(II)-binding groups and studied the molecular mechanisms underlying its biological toxicity. Our results show that both the compound, 4, and its copper(II) complex, Cu.4, are active against Candida spp. We found that Cu.4 acts as a copper(II) ionophore, which results in the intracellular accumulation of reactive oxygen species (ROS), whereas compound 4 is an iron chelator and exerts its toxicity by decreasing iron bioavailability. Interestingly, while 4 is not very toxic to macrophages or HeLa cells, Cu.4 significantly affects their viability. Overall, this work provides evidence of how copper can be combined with azoles to deregulate copper homeostasis, opening new horizons for the development of bifunctional antifungals.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Candida/efectos de los fármacos , Cobre/química , Ionóforos/química , Triazoles/química , Triazoles/farmacología , Antifúngicos/toxicidad , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Triazoles/toxicidad
5.
Public Health ; 188: 18-20, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33049491

RESUMEN

OBJECTIVES: With COVID-19 infections resulting in death according to a hierarchy of risks, with age and pre-existing health conditions enhancing disease severity, the objective of this study is to estimate the condition-specific case fatality ratio (CFR) for different subpopulations in Italy. STUDY DESIGN: The design of the study was to estimate the 'pre-existing comorbidity'-conditional CFR to eventually explain the mortality risk variability reported around in different countries. METHODS: We use the available information on pre-existing health conditions identified for deceased patients 'positive with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)' in Italy. We (i) estimated the total number of deaths for different pre-existing health conditions categories and (ii) calculated a conditional CFR based upon the number of comorbidities before SARS-CoV-2 infection. RESULTS: Our results show a 0.6% conditional CFR for a population with zero pre-existing pathology, increasing to 13.9% for a population diagnosed with one and more pre-existing health conditions. CONCLUSIONS: Condition-specific mortality risks are important to be evaluated during the COVID-19 pandemic, with potential elements to explain the CFR variability around the globe. A careful postmortem examination of deceased cases to differentiate death 'caused by COVID-19' from death 'positive with SARS-CoV-2' is therefore urgently needed and will likely improve our understanding of the COVID-19 mortality risk and virus pathogenicity.


Asunto(s)
Infecciones por Coronavirus/mortalidad , Salud Global/estadística & datos numéricos , Pandemias , Neumonía Viral/mortalidad , COVID-19 , Comorbilidad , Infecciones por Coronavirus/epidemiología , Humanos , Italia/epidemiología , Neumonía Viral/epidemiología , Medición de Riesgo
6.
Allergol Immunopathol (Madr) ; 47(5): 417-424, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31235184

RESUMEN

INTRODUCTION: The association regarding the atopic sensitization to mite aeroallergens and the socio-environmental features is still inconsistent. OBJECTIVES: We analyzed the role played by socioeconomic and environmental factors in the prevalence of sensitization to house dust mite (HDM) allergens, and associated with the risk of developing asthma symptoms. PATIENTS AND METHODS: This is a case-control study conducted with 108 patients, aged 1-17. We inquired about family habits, socioeconomic and environmental features. We applied the International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: We observed patients sensitized to all HDM tested, Derp (42%), Derf (37%) and Blot (33%). Middle family income (OR: 2.74; CI95%: 1.127-6.684), exposure to dog (OR: 3.758, CI95%: 1.127-6.684) and artificial climatization (OR: 4.319, CI95%: 1.398-13.348) were associated with sensitization to Derp. We also observed protective factors, such as sharing of dormitories, washing cycle for bedspreads and the presence of basic sanitation. An increased risk of sensitization to Derf was associated with Blot sensitization (OR: 3.172, CI95%: 1.083-9.292) and presence of mold on the walls (OR: 3.095, CI95%: 1.063-9.008). A protective factor was dormitory sharing. For sensitization to Blot, we observed an increase in the risk associated with Derp sensitization (OR: 3.462, CI95%: 1.191-10.061) and exposure to dog (OR: 3.255, CI95%: 0.987-10.736). In addition, sensitization to Blot increases the risk of developing asthma symptoms (OR: 2.732, CI95%: 0.981-7.606). CONCLUSION: Our data show distinct sociodemographic and environmental relations that lead to HDM sensitization and increased probability of development of allergic diseases.


Asunto(s)
Asma/epidemiología , Exposición a Riesgos Ambientales/efectos adversos , Hipersensibilidad/epidemiología , Factores Socioeconómicos , Adolescente , Animales , Antígenos Dermatofagoides/inmunología , Brasil/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Polvo , Femenino , Humanos , Lactante , Masculino , Prevalencia , Pyroglyphidae/inmunología
7.
Public Health ; 171: 31-40, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31082758

RESUMEN

OBJECTIVES: The aims of this study were (1) to identify attributes for patient safety at a primary healthcare level and (2) to analyze conceptions of patients, professionals, and managers about how these attributes are being addressed. STUDY DESIGN: This was a qualitative study. METHODS: Participants were recruited from three primary care settings in Brazil. A total of 37 subjects (four physicians, three nurses, three dentists, three managers, five community assistants, and 19 patients) participated on interviews about their perceptions of safety attributes at the primary care settings involved in the study. Some of these participants attended a focus group meeting. A thematic categorical analysis was carried out to interpret the interviews. RESULTS: The main attributes for patient safety were valued by the participants. However, barriers such as discontinuity of care, interruptions during consultations, breakdowns in the communication, and ineffective teamwork were reported as frequent sources of patient safety issues. Reports of patients left unattended for excessive time because of the lack of accurate information and disruptions that took up to 35 min show that there is still a long way to go for primary care to be safe and effective in the study settings. CONCLUSIONS: It is necessary that the strategies meet the patient safety needs more effectively and efficiently. Further research is needed to understand the complex nature of the problems that affect patient safety in these settings so that appropriate decisions can be made.


Asunto(s)
Evaluación de Necesidades , Seguridad del Paciente , Atención Primaria de Salud/organización & administración , Personal Administrativo/psicología , Personal Administrativo/estadística & datos numéricos , Adulto , Brasil , Comunicación , Femenino , Personal de Salud/psicología , Personal de Salud/estadística & datos numéricos , Humanos , Relaciones Interprofesionales , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Adulto Joven
8.
Phys Rev Lett ; 120(6): 067002, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29481286

RESUMEN

We study the relationship between the pseudogap and Fermi-surface topology in the two-dimensional Hubbard model by means of the cellular dynamical mean-field theory. We find two possible mean-field metallic solutions on a broad range of interactions, doping, and frustration: a conventional renormalized metal and an unconventional pseudogap metal. At half filling, the conventional metal is more stable and displays an interaction-driven Mott metal-insulator transition. However, for large interactions and small doping, a region that is relevant for cuprates, the pseudogap phase becomes the ground state. By increasing doping, we show that a first-order transition from the pseudogap to the conventional metal is tied to a change of the Fermi surface from hole- to electronlike, unveiling a correlation-driven mechanism for a Lifshitz transition. This explains the puzzling link between the pseudogap phase and Fermi surface topology that has been pointed out in recent experiments.

9.
Med Oral Patol Oral Cir Bucal ; 23(1): e1-e6, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29274148

RESUMEN

BACKGROUND: Williams-Beuren syndrome (WBS; OMIM #194050) is a developmental disorder characterized by congenital heart disease, intellectual disability, dysmorphic facial features and ophthalmologic abnormalities. Oral abnormalities are also described in clinical manifestations of the disease. This paper describes orofacial features in patients with WBS. MATERIAL AND METHODS: Seventeen patients with a confirmed molecular diagnosis of WBS were examined for oral abnormalities through clinical oral evaluations and panoramic radiography. RESULTS: Malocclusion, specifically with dental midline deviation, and high-arched palate were the most common findings. CONCLUSIONS: The present results contribute to knowledge on the orofacial manifestations of WBS. Since such patients with WBS may develop severe oral abnormalities, early detection and treatment can help improve their quality of life.


Asunto(s)
Anomalías Múltiples , Maloclusión/complicaciones , Anomalías Dentarias/complicaciones , Síndrome de Williams/complicaciones , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Adulto Joven
11.
Phys Rev Lett ; 117(5): 056402, 2016 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-27517782

RESUMEN

We present a theoretical investigation of the electronic structure of rutile (metallic) and M_{1} and M_{2} monoclinic (insulating) phases of VO_{2} employing a fully self-consistent combination of density functional theory and embedded dynamical mean field theory calculations. We describe the electronic structure of the metallic and both insulating phases of VO_{2}, and propose a distinct mechanism for the gap opening. We show that Mott physics plays an essential role in all phases of VO_{2}: undimerized vanadium atoms undergo classical Mott transition through local moment formation (in the M_{2} phase), while strong superexchange within V dimers adds significant dynamic intersite correlations, which remove the singularity of self-energy for dimerized V atoms. The resulting transition from rutile to dimerized M_{1} phase is adiabatically connected to the Peierls-like transition, but is better characterized as the Mott transition in the presence of strong intersite exchange. As a consequence of Mott physics, the gap in the dimerized M_{1} phase is temperature dependent. The sole increase of electronic temperature collapses the gap, reminiscent of recent experiments.

12.
Nature ; 460(7253): 384-7, 2009 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-19606148

RESUMEN

In recent years, strikingly consistent patterns of biodiversity have been identified over space, time, organism type and geographical region. A neutral theory (assuming no environmental selection or organismal interactions) has been shown to predict many patterns of ecological biodiversity. This theory is based on a mechanism by which new species arise similarly to point mutations in a population without sexual reproduction. Here we report the simulation of populations with sexual reproduction, mutation and dispersal. We found simulated time dependence of speciation rates, species-area relationships and species abundance distributions consistent with the behaviours found in nature. From our results, we predict steady speciation rates, more species in one-dimensional environments than two-dimensional environments, three scaling regimes of species-area relationships and lognormal distributions of species abundance with an excess of rare species and a tail that may be approximated by Fisher's logarithmic series. These are consistent with dependences reported for, among others, global birds and flowering plants, marine invertebrate fossils, ray-finned fishes, British birds and moths, North American songbirds, mammal fossils from Kansas and Panamanian shrubs. Quantitative comparisons of specific cases are remarkably successful. Our biodiversity results provide additional evidence that species diversity arises without specific physical barriers. This is similar to heavy traffic flows, where traffic jams can form even without accidents or barriers.


Asunto(s)
Biodiversidad , Especiación Genética , Reproducción/fisiología , Animales , Trastornos del Desarrollo Sexual , Extinción Biológica , Genotipo , Haploidia , Modelos Biológicos , Mutación/genética , Dinámica Poblacional , Reproducción/genética , Conducta Sexual Animal , Factores de Tiempo
13.
Ecol Lett ; 17(3): 273-83, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24304967

RESUMEN

Spatial structure in landscapes impacts population stability. Two linked components of stability have large consequences for persistence: first, statistical stability as the lack of temporal fluctuations; second, synchronisation as an aspect of dynamic stability, which erodes metapopulation rescue effects. Here, we determine the influence of river network structure on the stability of riverine metapopulations. We introduce an approach that converts river networks to metapopulation networks, and analytically show how fluctuation magnitude is influenced by interaction structure. We show that river metapopulation complexity (in terms of branching prevalence) has nonlinear dampening effects on population fluctuations, and can also buffer against synchronisation. We conclude by showing that river transects generally increase synchronisation, while the spatial scale of interaction has nonlinear effects on synchronised dynamics. Our results indicate that this dual stability - conferred by fluctuation and synchronisation dampening - emerges from interaction structure in rivers, and this may strongly influence the persistence of river metapopulations.


Asunto(s)
Ecosistema , Modelos Biológicos , Dinámica Poblacional , Ríos , Simulación por Computador , Especificidad de la Especie
14.
Epidemiol Infect ; 142(11): 2447-59, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25267408

RESUMEN

Models describing dengue epidemics are parametrized on disease incidence data and therefore high-quality data are essential. For Thailand, two different sources of long-term dengue data are available, the hard copy data from 1980 to 2005, where hospital admission cases were notified, and the electronic files, from 2003 to the present, where clinically classified forms of disease, i.e. dengue fever, dengue haemorrhagic fever, and dengue shock syndrome, are notified using separate files. The official dengue notification data, provided by the Bureau of Epidemiology, Ministry of Public Health in Thailand, were cross-checked with dengue data used in recent publications, where an inexact continuous time-series was observed to be consistently used since 2003, affecting considerably the model dynamics and its correct application. In this paper, numerical analysis and simulation techniques giving insights on predictability are performed to show the effects of model parametrization by using different datasets.


Asunto(s)
Bases de Datos Factuales , Dengue/epidemiología , Modelos Estadísticos , Dengue/diagnóstico , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Prevalencia , Sensibilidad y Especificidad , Dengue Grave/diagnóstico , Dengue Grave/epidemiología , Tailandia/epidemiología
15.
Allergol Immunopathol (Madr) ; 42(5): 493-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23830308

RESUMEN

The aim of this study was to systematically review the safety and efficacy of inhaled beclomethasone for asthma treatment in pregnant women. We performed a systematic review in Medline, LILACS and SciELO electronic databases in December 2012. A total of 3433 articles were found by using the keywords asthma, pregnancy and beclomethasone. Among these, 1666 were from Medline, via PubMed, and 1767 were from LILACS and SciELO. Nine of these articles were selected. Only one paper suggested an increased foetal risk for congenital malformations, and one other for offspring endocrine and metabolic disturbances. Data are mostly reassuring, supporting the use of glucocorticoid inhalants during pregnancy, and we found no evidence of inferiority in relation to efficacy and safety of beclomethasone compared to other drugs used in pregnant asthmatic women.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Beclometasona/uso terapéutico , Complicaciones del Embarazo/tratamiento farmacológico , Administración por Inhalación , Femenino , Humanos , Embarazo
17.
Phys Rev Lett ; 110(6): 066401, 2013 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-23432281

RESUMEN

We present a large N solution of a microscopic model describing the Mott-Anderson transition on a finite-coordination Bethe lattice. Our results demonstrate that strong spatial fluctuations, due to Anderson localization effects, dramatically modify the quantum critical behavior near disordered Mott transitions. The leading critical behavior of quasiparticle wave functions is shown to assume a universal form in the full range from weak to strong disorder, in contrast to disorder-driven non-Fermi liquid ("electronic Griffiths phase") behavior, which is found only in the strongly correlated regime.

18.
Nat Genet ; 7(1): 91-7, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8075648

RESUMEN

The genetics of Wilms' tumour (WT), a paediatric malignancy of the kidney, is complex. Inactivation of the tumour suppressor gene, WT1, is associated with tumour aetiology in approximately 10-15% of WTs. Chromosome 17p changes have been noted in cytogenetic studies of WTs, prompting us to screen 140 WTs for p53 mutations. When histopathology reports were available, p53 mutations were present in eight of eleven anaplastic WTs, a tumour subtype associated with poor prognosis. Amplification of MDM2, a gene whose product binds and sequesters p53, was excluded. Our results indicate that p53 alterations provide a molecular marker for anaplastic WTs.


Asunto(s)
Genes p53 , Neoplasias Renales/genética , Proteínas Nucleares , Proteínas Proto-Oncogénicas , Tumor de Wilms/genética , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Diferenciación Celular , Análisis Mutacional de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Renales/patología , Masculino , Datos de Secuencia Molecular , Proteínas de Neoplasias/genética , Reacción en Cadena de la Polimerasa , Pronóstico , Proteínas Proto-Oncogénicas c-mdm2 , Proteína p53 Supresora de Tumor/biosíntesis , Tumor de Wilms/patología
19.
Oxf Open Neurosci ; 2: kvad010, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38596242

RESUMEN

Pigs are an important large animal model for translational clinical research but underutilized in behavioral neuroscience. This is due, in part, to a lack of rigorous neurocognitive assessments for pigs. Here, we developed a new automated T-maze for pigs that takes advantage of their natural tendency to alternate. The T-maze has obvious cross-species value having served as a foundation for cognitive theories across species. The maze (17' × 13') was constructed typically and automated with flanking corridors, guillotine doors, cameras, and reward dispensers. We ran nine pigs in (1) a simple alternation task and (2) a delayed spatial alternation task. Our assessment focused on the delayed spatial alternation task which forced pigs to wait for random delays (5, 60, 120, and 240 s) and burdened spatial working memory. We also looked at self-paced trial latencies, error types, and coordinate-based video tracking. We found pigs naturally alternated but performance declined steeply across delays (R2 = 0.84). Self-paced delays had no effect on performance suggestive of an active interference model of working memory. Positional and head direction data could differentiate subsequent turns on short but not long delays. Performance levels were stable over weeks in diverse strains and sexes, and thus provide a benchmark for future neurocognitive assessments in pigs.

20.
Genet Mol Res ; 11(3): 2559-68, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22869076

RESUMEN

The causal agent of witches' broom disease, Moniliophthora perniciosa is a hemibiotrophic and endemic fungus of the Amazon basin and the most important cocoa disease in Brazil. The purpose of this study was to analyze the genetic diversity of polysporic isolates of M. perniciosa to evaluate the adaptation of the pathogen from different Brazilian regions and its association with different hosts. Polysporic isolates obtained previously in potato dextrose agar cultures of M. perniciosa from different Brazilian states and different hosts (Theobroma cacao, Solanum cernuum, S. paniculatum, S. lycocarpum, Solanum sp, and others) were analyzed by somatic compatibility grouping where the mycelium interactions were distinguished after 4-8 weeks of confrontation between the different isolates of M. perniciosa based on the precipitation line in the transition zone and by protein electrophoresis through SDS-PAGE. The diversity of polysporic isolates of M. perniciosa was grouped according to geographic proximity and respective hosts. The great genetic diversity of M. perniciosa strains from different Brazilian states and hosts favored adaptation in unusual environments and dissemination at long distances generating new biotypes.


Asunto(s)
Agaricales/genética , Agaricales/aislamiento & purificación , Variación Genética , Esporas Fúngicas/genética , Agaricales/fisiología , Brasil , Cacao/microbiología , Filogenia
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