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1.
Environ Res ; 249: 118346, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38311204

RESUMEN

Quantitative next-generation sequencing techniques have been critical in gaining a better understanding of microbial ecosystems. In soils, denitrifying microorganisms are responsible for dinitrogen (N2) production. The nosZ gene codes for nitrous oxide reductase, the enzyme facilitating the reduction of nitrous oxide (N2O) to N2. The objectives of this research were to: 1) understand how soil depth influences RNA concentration and nosZ gene abundance; 2) assess the spatial dependence of nosZ gene abundance in two claypan soil fields; and 3) compare and evaluate multiple RNA-based sequencing methods for quantifying nosZ gene abundance in soils in relation to dinitrogen (N2) production. Research sites consisted of two intensively studied claypan soil fields in Central Missouri, USA. Soil cores were collected from two landscape transects across both fields and analyzed for extractable soil RNA at two depths (0-15 cm and 15-30 cm). Measurements of nosZ gene abundance were obtained using real-time quantitative polymerase chain reaction (RT-qPCR), droplet digital polymerase chain reaction (ddPCR), and nanostring sequencing (NS). In both fields, soil RNA concentrations were significantly greater at 0-15 cm depth compared to 15-30 cm. These data indicated low overall soil microbial activity below 15 cm. Due to low quantities of extractable soil RNA in the subsoil, nosZ gene abundance was only determined in the 0-15 cm depth. Sequencing method comparisons of average nosZ gene abundance showed that NS results were constrained to a narrow range and were 10-20-fold lower than ddPCR and RT-qPCR at each landscape position within each field. Droplet digital PCR appears to be the most promising method, as it reflected changes in N2 production across landscape position.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Microbiología del Suelo , Suelo , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Missouri , Oxidorreductasas/genética , Suelo/química
2.
J Neurosci ; 39(7): 1206-1221, 2019 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-30541908

RESUMEN

Song learning in zebra finches (Taeniopygia guttata) requires exposure to the song of a tutor, resulting in an auditory memory. This memory is the foundation for later sensorimotor learning, resulting in the production of a copy of the tutor's song. The cortical premotor nucleus HVC (proper name) is necessary for auditory and sensorimotor learning as well as the eventual production of adult song. We recently discovered that the intrinsic physiology of HVC neurons changes across stages of song learning, but are those changes the result of learning or are they experience-independent developmental changes? To test the role of auditory experience in driving intrinsic changes, patch-clamp experiments were performed comparing HVC neurons in juvenile birds with varying amounts of tutor exposure. The intrinsic physiology of HVC neurons changed as a function of tutor exposure. Counterintuitively, tutor deprivation resulted in juvenile HVC neurons showing an adult-like phenotype not present in tutor-exposed juveniles. Biophysical models were developed to predict which ion channels were modulated by experience. The models indicate that tutor exposure transiently suppressed the Ih and T-type Ca2+ currents in HVC neurons that target the basal ganglia, whereas tutor exposure increased the resting membrane potential and decreased the spike amplitude in HVC neurons that drive singing. Our findings suggest that intrinsic plasticity may be part of the mechanism for auditory learning in the HVC. More broadly, models of learning and memory should consider intrinsic plasticity as a possible mechanism by which the nervous system encodes the lasting effects of experience.SIGNIFICANCE STATEMENT It is well established that learning involves plasticity of the synapses between neurons. However, the activity of a neural circuit can also be dramatically altered by changes in the intrinsic properties (ion channels) of the component neurons. The present experiments show experience-dependent changes in the intrinsic physiology of neurons in the cortical premotor nucleus HVC (proper name) in juvenile zebra finches (Taeniopygia guttata) during auditory learning of a tutor's song. Tutor deprivation does not "arrest" development of intrinsic properties, but rather results in neurons with a premature adult-like physiological phenotype. It is possible that auditory learning involves a form of nonsynaptic plasticity and that experience-dependent suppression of specific ion channels may work in concert with synaptic plasticity to promote vocal learning.


Asunto(s)
Percepción Auditiva/fisiología , Pinzones/fisiología , Aprendizaje/fisiología , Plasticidad Neuronal/fisiología , Animales , Ganglios Basales/fisiología , Canales de Calcio Tipo T/fisiología , Corteza Cerebral/fisiología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/fisiología , Canales Iónicos/fisiología , Masculino , Potenciales de la Membrana/fisiología , Ratones , Vocalización Animal
3.
J Cell Physiol ; 233(4): 2681-2692, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28833090

RESUMEN

CRSBP-1 (mammalian LYVE-1) is a membrane glycoprotein highly expressed in lymphatic endothelial cells (LECs). It has multiple ligands, including hyaluronic acid (HA) and growth factors/cytokines (e.g., PDGF-BB and VEGF-A) containing CRS motifs (clusters of basic amino-acid residues). The ligand binding activities are mediated by Link module and acidic-amino-acid-rich (AAAR) domains, respectively. These CRSBP-1/LYVE-1 ligands have been shown to induce opening of lymphatic intercellular junctions in LEC monolayers and in lymphatic vessels in wild-type mice. We hypothesize that CRSBP-1/LYVE-1 ligands, particularly CRS-containing growth factors/cytokines, are secreted by immune and cancer cells for lymphatic entry during adaptive immune responses and lymphatic metastasis. We have looked into the origin of the Link module and AAAR domain of LYVE-1 in evolution and its association with the development of lymph nodes and efficient adaptive immunity. Lymph nodes represent the only major recent innovation of the adaptive immune systems in evolution particularly to mammals and bird. Here we demonstrate that the development of the LYVE-1 gene with the AAAR domain in evolution is associated with acquisition of lymph nodes and adaptive immunity. LYVE-1 from other species, which have no lymph nodes, lack the AAAR domain and efficient adaptive immunity. Synthetic CRSBP-1 ligands PDGF and VEGF peptides, which contain the CRS motifs of PDGF-BB and VEGF-A, respectively, specifically bind to CRSBP-1 but do not interact with either PDGFßR or VEGFR2. These peptides function as adjuvants by enhancing adaptive immunity of pseudorabies virus (PRV) vaccine in pigs. These results support the notion that LYVE-1 is involved in adaptive immunity in mammals.


Asunto(s)
Inmunidad Adaptativa , Aminoácidos Acídicos/metabolismo , Evolución Molecular , Ganglios Linfáticos/inmunología , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Inmunidad Adaptativa/efectos de los fármacos , Adyuvantes Inmunológicos/farmacología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Femenino , Ligandos , Ganglios Linfáticos/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Péptidos/farmacología , Filogenia , Factor de Crecimiento Derivado de Plaquetas/farmacología , Dominios Proteicos , Vacunas contra la Seudorrabia/inmunología , Alineación de Secuencia , Tiburones , Homología Estructural de Proteína , Relación Estructura-Actividad , Sus scrofa , Factor A de Crecimiento Endotelial Vascular/farmacología , Pez Cebra
4.
J Neurophysiol ; 120(3): 1186-1197, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29924715

RESUMEN

Male zebra finches produce a sequence-invariant set of syllables, separated by short inspiratory gaps. These songs are learned from an adult tutor and maintained throughout life, making them a tractable model system for learned, sequentially ordered behaviors, particularly speech production. Moreover, much is known about the cortical, thalamic, and brain stem areas involved in producing this behavior, with the premotor cortical nucleus HVC (proper name) being of primary importance. In a previous study, our group developed a behavioral neural network model for birdsong constrained by the structural connectivity of the song system, the signaling properties of individual neurons and circuits, and circuit-breaking behavioral studies. Here we describe a more computationally tractable model and use it to explain the behavioral effects of unilateral cooling and electrical stimulations of HVC on song production. The model demonstrates that interhemispheric switching of song control is sufficient to explain these results, consistent with the hypotheses proposed when the experiments were initially conducted. Finally, we use the model to make testable predictions that can be used to validate the model framework and explain the effects of other perturbations of the song system, such as unilateral ablations of the primary input and output nuclei of HVC. NEW & NOTEWORTHY In this report, we propose a two-hemisphere neural network model for the bilaterally symmetrical song system underlying birdsong in the male zebra finch. This model captures the behavioral effects of unilateral cooling and electrical stimulations of the premotor cortical nucleus HVC during song production, supporting the hypothesis of interhemispheric switching of song control. We use the model to make testable predictions regarding the behavioral effects of other unilateral perturbations to the song system.


Asunto(s)
Lateralidad Funcional , Modelos Neurológicos , Corteza Motora/fisiología , Redes Neurales de la Computación , Neuronas/fisiología , Vocalización Animal/fisiología , Animales , Frío , Estimulación Eléctrica , Pinzones , Vías Nerviosas/fisiología
5.
J Cell Biochem ; 118(6): 1387-1400, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27862220

RESUMEN

For several decades, cholesterol has been thought to cause ASCVD. Limiting dietary cholesterol intake has been recommended to reduce the risk of the disease. However, several recent epidemiological studies do not support a relationship between dietary cholesterol and/or blood cholesterol and ASCVD. Consequently, the role of cholesterol in atherogenesis is now uncertain. Much evidence indicates that TGF-ß, an anti-inflammatory cytokine, protects against ASCVD and that suppression of canonical TGF-ß signaling (Smad2-dependent) is involved in atherogenesis. We had hypothesized that cholesterol causes ASCVD by suppressing canonical TGF-ß signaling in vascular endothelium. To test this hypothesis, we determine the effects of cholesterol, 7-dehydrocholesterol (7-DHC; the biosynthetic precursor of cholesterol), and other sterols on canonical TGF-ß signaling. We use Mv1Lu cells (a model cell system for studying TGF-ß activity) stably expressing the Smad2-dependent luciferase reporter gene. We demonstrate that 7-DHC (but not cholesterol or other sterols) effectively suppresses the TGF-ß-stimulated luciferase activity. We also demonstrate that 7-DHC suppresses TGF-ß-stimulated luciferase activity by promoting lipid raft/caveolae formation and subsequently recruiting cell-surface TGF-ß receptors from non-lipid raft microdomains to lipid rafts/caveolae where TGF-ß receptors become inactive in transducing canonical signaling and undergo rapid degradation upon TGF-ß binding. We determine this by cell-surface 125 I-TGF-ß-cross-linking and sucrose density gradient ultracentrifugation. We further demonstrate that methyl-ß-cyclodextrin (MßCD), a sterol-chelating agent, reverses 7-DHC-induced suppression of TGF-ß-stimulated luciferase activity by extrusion of 7-DHC from resident lipid rafts/caveolae. These results suggest that 7-DHC, but not cholesterol, promotes lipid raft/caveolae formation, leading to suppression of canonical TGF-ß signaling and atherogenesis. J. Cell. Biochem. 118: 1387-1400, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Aterosclerosis/metabolismo , Colesterol/farmacología , Deshidrocolesteroles/farmacología , Factor de Crecimiento Transformador beta/metabolismo , Caveolas/metabolismo , Línea Celular , Humanos , Microdominios de Membrana/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína Smad2/metabolismo
6.
J Neurophysiol ; 118(2): 677-692, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28381490

RESUMEN

Male zebra finches produce a song consisting of a canonical sequence of syllables, learned from a tutor and repeated throughout its adult life. Much of the neural circuitry responsible for this behavior is located in the cortical premotor region HVC (acronym is name). In a recent study from our laboratory, we found that partial bilateral ablation of the medial portion of HVC has effects on the song that are qualitatively different from those of bilateral ablation of the lateral portion. In this report we describe a neural network organization that can explain these data, and in so doing suggests key roles for other brain nuclei in the production of song. We also suggest that syllables and the gaps between them are each coded separately by neural chains within HVC, and that the timing mechanisms for syllables and gaps are distinct. The design principles underlying this model assign distinct roles for medial and lateral HVC circuitry that explain the data on medial and lateral ablations. In addition, despite the fact that the neural coding of song sequence is distributed among several brain nuclei in our model, it accounts for data showing that cooling of HVC stretches syllables uniformly and to a greater extent than gaps. Finally, the model made unanticipated predictions about details of the effects of medial and lateral HVC ablations that were then confirmed by reanalysis of these previously acquired behavioral data.NEW & NOTEWORTHY Zebra finch song consists of a string of syllables repeated in a nearly invariant sequence. We propose a neural network organization that can explain recent data indicating that the medial and lateral portions of the premotor cortical nucleus HVC have different roles in zebra finch song production. Our model explains these data, as well as data on the effects on song of cooling HVC, and makes predictions that we test in the singing bird.


Asunto(s)
Corteza Cerebral/fisiología , Pinzones/fisiología , Modelos Neurológicos , Neuronas/fisiología , Vocalización Animal/fisiología , Animales , Corteza Cerebral/fisiopatología , Aprendizaje/fisiología , Masculino , Vías Nerviosas/fisiología , Vías Nerviosas/fisiopatología , Espectrografía del Sonido , Sinapsis/fisiología , Temperatura , Factores de Tiempo
7.
J Cell Biochem ; 117(4): 860-71, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26419316

RESUMEN

Regular consumption of moderate amounts of ethanol has important health benefits on atherosclerotic cardiovascular disease (ASCVD). Overindulgence can cause many diseases, particularly alcoholic liver disease (ALD). The mechanisms by which ethanol causes both beneficial and harmful effects on human health are poorly understood. Here we demonstrate that ethanol enhances TGF-ß-stimulated luciferase activity with a maximum of 0.5-1% (v/v) in Mv1Lu cells stably expressing a luciferase reporter gene containing Smad2-dependent elements. In Mv1Lu cells, 0.5% ethanol increases the level of P-Smad2, a canonical TGF-ß signaling sensor, by ∼ 2-3-fold. Ethanol (0.5%) increases cell-surface expression of the type II TGF-ß receptor (TßR-II) by ∼ 2-3-fold from its intracellular pool, as determined by I(125) -TGF-ß-cross-linking/Western blot analysis. Sucrose density gradient ultracentrifugation and indirect immunofluorescence staining analyses reveal that ethanol (0.5% and 1%) also displaces cell-surface TßR-I and TßR-II from lipid rafts/caveolae and facilitates translocation of these receptors to non-lipid raft microdomains where canonical signaling occurs. These results suggest that ethanol enhances canonical TGF-ß signaling by increasing non-lipid raft microdomain localization of the TGF-ß receptors. Since TGF-ß plays a protective role in ASCVD but can also cause ALD, the TGF-ß enhancer activity of ethanol at low and high doses appears to be responsible for both beneficial and harmful effects. Ethanol also disrupts the location of lipid raft/caveolae of other membrane proteins (e.g., neurotransmitter, growth factor/cytokine, and G protein-coupled receptors) which utilize lipid rafts/caveolae as signaling platforms. Displacement of these membrane proteins induced by ethanol may result in a variety of pathologies in nerve, heart and other tissues.


Asunto(s)
Caveolas/efectos de los fármacos , Vesículas Citoplasmáticas/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Etanol/farmacología , Receptores de Factores de Crecimiento Transformadores beta/genética , Factor de Crecimiento Transformador beta/genética , Animales , Caveolas/química , Caveolas/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Fraccionamiento Celular , Línea Celular Transformada , Vesículas Citoplasmáticas/química , Vesículas Citoplasmáticas/metabolismo , Relación Dosis-Respuesta a Droga , Células Epiteliales/citología , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Genes Reporteros , Luciferasas/genética , Luciferasas/metabolismo , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Microdominios de Membrana/química , Microdominios de Membrana/efectos de los fármacos , Microdominios de Membrana/metabolismo , Visón , Fosforilación , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal , Proteína Smad2/genética , Proteína Smad2/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
8.
South Med J ; 109(11): 690-693, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27812708

RESUMEN

OBJECTIVES: To evaluate the effectiveness of pharmacist-physician collaboration in the treatment of type 2 diabetes mellitus (DM) with severe insulin resistance, using 500 U/mL concentrated regular insulin (U-500) in a primary care clinic that is not staffed by an endocrinologist. METHODS: A retrospective chart review was conducted searching for patients who were prescribed U-500 insulin from January 1, 2008 through December 31, 2014. Subjects were included in the analysis if the pharmacist initiated U-500 insulin therapy, received treatment for at least 6 months, and who attended at least one follow-up visit with the pharmacist. Anyone who received U-500 insulin before the initial pharmacist consultation, managed by an endocrinologist, or who was missing follow-up hemoglobin A1c (HbA1c) laboratory values during the follow-up period was excluded. The primary endpoint was the change in HbA1c from U-500 initiation to 6 months later. Secondary endpoints included changes in weight, confirmed hypoglycemia events, changes in other anti-DM medications and the number of pharmacist and primary care physician visits during the follow-up period. RESULTS: Eighty-one patients were identified and screened, and 44 patients were included in the analysis. Baseline HbA1c (mean ± standard deviation) was 9.7% ± 1.6% and decreased to 8.6% ± 1.6% after 6 months of follow-up, representing a reduction of 1.1% (95% confidence interval -1.6 to -0.6, P < 0.001). Body weight increased (mean ± standard deviation) by 6.7 ± 15.1 lb from baseline (P = 0.005). The frequency of confirmed hypoglycemia events was low (0.8 events per patient). Treatment with metformin was preserved, whereas most other DM medications were discontinued. A similar number of pharmacist and physician follow-up visits were completed by the end of the study period (2.0 and 2.7 visits, respectively; P = 0.805). CONCLUSIONS: Initiation of U-500 insulin by clinical pharmacists collaborating with primary care physicians results in improved DM control in patients with severe insulin resistance. Our findings suggest this interprofessional partnership provides an alternative referral approach for primary care physicians when endocrinology services are absent or limited.


Asunto(s)
Conducta Cooperativa , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Resistencia a la Insulina , Insulina/administración & dosificación , Farmacéuticos , Médicos de Atención Primaria , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Hipoglucemia/inducido químicamente , Masculino , Persona de Mediana Edad , Grupo de Atención al Paciente , Estudios Retrospectivos , Tennessee , Aumento de Peso
9.
J Neurosci ; 34(50): 16821-34, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25505334

RESUMEN

How the brain coordinates rapid sequences of learned behavior, such as human speech, remains a fundamental problem in neuroscience. Birdsong is a model of such behavior, which is learned and controlled by a neural circuit that spans avian cortex, basal ganglia, and thalamus. The songs of adult male zebra finches (Taeniopygia guttata), produced as rapid sequences of vocal gestures (syllables), are encoded by the cortical premotor region HVC (proper name). While the motor encoding of song within HVC has traditionally been viewed as unitary and distributed, we used an ablation technique to ask whether the sequence and structure of song are processed independently within HVC. Results revealed a functional topography across the medial-lateral axis of HVC. Bilateral ablation of medial HVC induced a positive disruption of song (increase in atypical syllable sequences), whereas bilateral ablation of lateral HVC induced a negative disruption (omission of individual syllables). Bilateral ablation of central HVC either had no effect on song or induced syllable omission, similar to lateral HVC ablation. We then investigated HVC connectivity and found parallel afferent and efferent pathways that transit medial and lateral HVC and converge at vocal motor cortex. In light of recent evidence that syntactic and lexical components of human speech are processed independently by neighboring regions of cortex (Menenti et al., 2012), our demonstration of anatomically distinct pathways that differentially process the sequence and structure of birdsong in parallel suggests that the vertebrate brain relies on a common approach to encode rapid sequences of vocal gestures.


Asunto(s)
Pinzones/fisiología , Centro Vocal Superior/fisiología , Corteza Motora/fisiología , Red Nerviosa/fisiología , Vocalización Animal/fisiología , Animales , Masculino , Pájaros Cantores
10.
Proc Natl Acad Sci U S A ; 109 Suppl 2: 17245-52, 2012 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-23045667

RESUMEN

Songbirds provide rich natural models for studying the relationships between brain anatomy, behavior, environmental signals, and gene expression. Under the Songbird Neurogenomics Initiative, investigators from 11 laboratories collected brain samples from six species of songbird under a range of experimental conditions, and 488 of these samples were analyzed systematically for gene expression by microarray. ANOVA was used to test 32 planned contrasts in the data, revealing the relative impact of different factors. The brain region from which tissue was taken had the greatest influence on gene expression profile, affecting the majority of signals measured by 18,848 cDNA spots on the microarray. Social and environmental manipulations had a highly variable impact, interpreted here as a manifestation of paradoxical "constitutive plasticity" (fewer inducible genes) during periods of enhanced behavioral responsiveness. Several specific genes were identified that may be important in the evolution of linkages between environmental signals and behavior. The data were also analyzed using weighted gene coexpression network analysis, followed by gene ontology analysis. This revealed modules of coexpressed genes that are also enriched for specific functional annotations, such as "ribosome" (expressed more highly in juvenile brain) and "dopamine metabolic process" (expressed more highly in striatal song control nucleus area X). These results underscore the complexity of influences on neural gene expression and provide a resource for studying how these influences are integrated during natural experience.


Asunto(s)
Encéfalo/fisiología , Pájaros Cantores/genética , Pájaros Cantores/fisiología , Animales , Conducta Animal/fisiología , Encéfalo/anatomía & histología , Encéfalo/crecimiento & desarrollo , Femenino , Alimentos , Interacción Gen-Ambiente , Masculino , Transducción de Señal/genética , Conducta Social , Pájaros Cantores/anatomía & histología , Pájaros Cantores/crecimiento & desarrollo , Especificidad de la Especie , Transcriptoma , Vocalización Animal/fisiología
11.
Ann Surg Oncol ; 21(3): 733-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24046113

RESUMEN

The incidence of breast cancer has been on the rise in the United States over the past several decades. The advanced longevity of the population during this same time period, specifically of elderly women, translates to increases in the absolute number of women diagnosed with breast cancer yearly. This, in combination with decreasing mortality rates, has now led to an increase in the number of breast cancer survivors who need long-term follow-up. There has been significant debate over what tests should be obtained, how often they should be obtained, how long surveillance should be continued, and by whom this should be performed. We review the published guidelines for surveillance, available data regarding low- versus high-intensity surveillance plans, current practice patterns, and recommendations for future strategies.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/cirugía , Continuidad de la Atención al Paciente , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Pruebas Diagnósticas de Rutina/tendencias , Femenino , Estudios de Seguimiento , Humanos , Vigilancia de la Población , Pronóstico , Tasa de Supervivencia , Sobrevivientes
12.
J Environ Qual ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816346

RESUMEN

The Lower Mississippi River Basin-Long-Term Agroecosystem Research Site (LMRB-LTAR) encompasses six states from Missouri to the Gulf of Mexico and is coordinated by the USDA-ARS National Sedimentation Laboratory, Oxford, MS. The overarching goal of LTAR is to assess regionally diverse and geographically scalable farming practices for enhanced sustainability of agroecosystem goods and services under changing environment and resource-use conditions. The LMRB-LTAR overall goal is to assess sustainable row crop agricultural production systems that integrate regional environmental and socioeconomic needs. Primary row crops in the region include soybeans, corn, cotton, rice, and sugarcane with crop rotations influenced by commodity crop price and other factors. The field-scale common experiment (CE) includes four row crop farms (26-101 ha) established in 2021 and 2023. Three fields are managed with alternative practices, including reduced tillage, cover crops, and automated prescription irrigation, and three fields are managed with prevailing farming practices, consisting of conventional tillage, no cover crop, and nonprescription irrigation. Treatment effects on crop productivity, soil quality, water use efficiency, water quality, and carbon storage are assessed. Research from the LMRB CE will deliver outcomes linked to overarching LTAR network goals, including innovative agricultural systems, strengthened partnerships, data management technologies, and precision environmental tools.

13.
J Neurosci ; 32(27): 9312-22, 2012 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-22764238

RESUMEN

Neural activity within HVC (proper name), a premotor nucleus of the songbird telencephalon analogous to premotor cortical regions in mammals, controls the temporal structure of learned song in male zebra finches (Taeniopygia guttata). HVC is composed of a superficially isomorphic neuronal mosaic, implying that song is encoded in a distributed network within HVC. Here, we combined HVC microlesions (10% focal ablation) with singing-driven immediate-early gene (IEG) labeling to explore the network architecture of HVC during singing. Microlesions produce a transient disruption of HVC activity that results in a temporary (≈ 1 week) loss of vocal patterning. Results showed an asymmetrical reduction in the density of IEG-labeled cells 3-5 d after microlesions: swaths of unlabeled cells extended rostrally and/or caudally depending on the position of the HVC microlesion. Labeling returned once birds recovered their songs. Axial swaths of unlabeled cells occurred whether microlesions were located at rostral or caudal poles of HVC, indicating that the localized reduction in IEG labeling could not be attributable solely to transection of afferents that enter HVC rostrally. The asymmetrical pattern of reduced IEG labeling could be explained if synaptic connectivity within HVC is organized preferentially within the rostrocaudal axis. In vivo retrograde tracer injections and in vitro stimulation and recording experiments in horizontal slices of HVC confirmed a rostrocaudal organization of HVC neural connectivity. Our findings suggest that HVC contains an axially organized network architecture that may encode the temporal structure of song.


Asunto(s)
Pinzones/fisiología , Centro Vocal Superior/fisiología , Aprendizaje/fisiología , Telencéfalo/anatomía & histología , Telencéfalo/fisiología , Animales , Daño Encefálico Crónico/patología , Daño Encefálico Crónico/fisiopatología , Desnervación/métodos , Electrofisiología , Pinzones/anatomía & histología , Centro Vocal Superior/anatomía & histología , Centro Vocal Superior/lesiones , Masculino , Técnicas de Cultivo de Órganos , Vocalización Animal/fisiología
14.
J Neurophysiol ; 110(5): 1227-45, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23719205

RESUMEN

The nucleus HVC (proper name) within the avian analog of mammal premotor cortex produces stereotyped instructions through the motor pathway leading to precise, learned vocalization by songbirds. Electrophysiological characterization of component HVC neurons is an important requirement in building a model to understand HVC function. The HVC contains three neural populations: neurons that project to the RA (robust nucleus of arcopallium), neurons that project to Area X (of the avian basal ganglia), and interneurons. These three populations are interconnected with specific patterns of excitatory and inhibitory connectivity, and they fire with characteristic patterns both in vivo and in vitro. We performed whole cell current-clamp recordings on HVC neurons within brain slices to examine their intrinsic firing properties and determine which ionic currents are responsible for their characteristic firing patterns. We also developed conductance-based models for the different neurons and calibrated the models using data from our brain slice work. These models were then used to generate predictions about the makeup of the ionic currents that are responsible for the different responses to stimuli. These predictions were then tested and verified in the slice using pharmacological manipulations. The model and the slice work highlight roles of a hyperpolarization-activated inward current (Ih), a low-threshold T-type Ca(2+) current (ICa-T), an A-type K(+) current (IA), a Ca(2+)-activated K(+) current (ISK), and a Na(+)-dependent K(+) current (IKNa) in driving the characteristic neural patterns observed in the three HVC neuronal populations. The result is an improved characterization of the HVC neurons responsible for song production in the songbird.


Asunto(s)
Potenciales de Acción , Centro Vocal Superior/fisiología , Modelos Neurológicos , Neuronas/fisiología , Animales , Pinzones/fisiología , Técnicas In Vitro , Masculino
15.
J Cell Sci ; 124(Pt 8): 1231-44, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21444752

RESUMEN

Cell-surface retention sequence (CRS) binding protein (CRSBP-1) is a membrane glycoprotein identified by its ability to bind PDGF-BB and VEGF-A via their CRS motifs (clusters of basic amino acid residues). CRSBP-1 is identical to LYVE-1 and exhibits dual ligand (CRS-containing proteins and hyaluronic acid) binding activity, suggesting the importance of CRSBP-1 ligands in lymphatic function. Here, we show that CRSBP-1 ligands induce disruption of VE-cadherin-mediated intercellular adhesion and opening of intercellular junctions in lymphatic endothelial cell (LEC) monolayers as determined by immunofluorescence microscopy and Transwell permeability assay. This occurs by interaction with CRSBP-1 in the CRSBP-1-PDGFßR-ß-catenin complex, resulting in tyrosine phosphorylation of the complex, dissociation of ß-catenin and p120-catenin from VE-cadherin, and internalization of VE-cadherin. Pretreatment of LECs with a PDGFßR kinase inhibitor abolishes ligand-stimulated tyrosine phosphorylation of VE-cadherin, halts the ligand-induced disruption of VE-cadherin intercellular adhesion and blocks the ligand-induced opening of intercellular junctions. These CRSBP-1 ligands also induce opening of lymphatic intercellular junctions that respond to PDGFßR kinase inhibitor in wild-type mice (but not in Crsbp1-null mice) as evidenced by increased transit of injected FITC-dextran and induced edema fluid from the interstitial space into lymphatic vessels. These results disclose a novel mechanism involved in the opening of lymphatic intercellular junctions.


Asunto(s)
Antígenos CD/metabolismo , Cadherinas/metabolismo , Células Endoteliales/fisiología , Proteínas de la Membrana/metabolismo , Tirosina/metabolismo , Animales , Antígenos CD/genética , Cadherinas/genética , Adhesión Celular , Línea Celular , Ácido Hialurónico/metabolismo , Ligandos , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Unión Proteica , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
16.
Microb Ecol ; 65(4): 1024-38, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23508733

RESUMEN

In May of 2011, a live mass stranding of 26 short-finned pilot whales (Globicephala macrorhynchus) occurred in the lower Florida Keys. Five surviving whales were transferred from the original stranding site to a nearby marine mammal rehabilitation facility where they were constantly attended to by a team of volunteers. Bacteria cultured during the routine clinical care of the whales and necropsy of a deceased whale included methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA). In order to investigate potential sources or reservoirs of MSSA and MRSA, samples were obtained from human volunteers, whales, seawater, and sand from multiple sites at the facility, nearby recreational beaches, and a canal. Samples were collected on 3 days. The second collection day was 2 weeks after the first, and the third collection day was 2 months after the last animal was removed from the facility. MRSA and MSSA were isolated on each day from the facility when animals and volunteers were present. MSSA was found at an adjacent beach on all three collection days. Isolates were characterized by utilizing a combination of quantitative real-time PCR to determine the presence of mecA and genes associated with virulence, staphylococcal protein A typing, staphylococcal cassette chromosome mec typing, multilocus sequence typing, and pulsed field gel electrophoresis (PFGE). Using these methods, clonally related MRSA were isolated from multiple environmental locations as well as from humans and animals. Non-identical but genetically similar MSSA and MRSA were also identified from distinct sources within this sample pool. PFGE indicated that the majority of MRSA isolates were clonally related to the prototype human strain USA300. These studies support the notion that S. aureus may be shed into an environment by humans or pilot whales and subsequently colonize or infect exposed new hosts.


Asunto(s)
Cetáceos/microbiología , Ballena de Aleta/microbiología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/veterinaria , Animales , Antibacterianos/farmacología , Florida , Humanos , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Voluntarios
17.
Nature ; 448(7157): 1050-3, 2007 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-17660834

RESUMEN

A dense map of genetic variation in the laboratory mouse genome will provide insights into the evolutionary history of the species and lead to an improved understanding of the relationship between inter-strain genotypic and phenotypic differences. Here we resequence the genomes of four wild-derived and eleven classical strains. We identify 8.27 million high-quality single nucleotide polymorphisms (SNPs) densely distributed across the genome, and determine the locations of the high (divergent subspecies ancestry) and low (common subspecies ancestry) SNP-rate intervals for every pairwise combination of classical strains. Using these data, we generate a genome-wide haplotype map containing 40,898 segments, each with an average of three distinct ancestral haplotypes. For the haplotypes in the classical strains that are unequivocally assigned ancestry, the genetic contributions of the Mus musculus subspecies--M. m. domesticus, M. m. musculus, M. m. castaneus and the hybrid M. m. molossinus--are 68%, 6%, 3% and 10%, respectively; the remaining 13% of haplotypes are of unknown ancestral origin. The considerable regional redundancy of the SNP data will facilitate imputation of the majority of these genotypes in less-densely typed classical inbred strains to provide a complete view of variation in additional strains.


Asunto(s)
Ratones Endogámicos/genética , Polimorfismo de Nucleótido Simple/genética , Animales , Cromosomas de los Mamíferos/genética , Análisis Mutacional de ADN , Bases de Datos Genéticas , Genoma/genética , Genómica , Haplotipos/genética , Ratones , Ratones Endogámicos C57BL , Análisis de Secuencia por Matrices de Oligonucleótidos
18.
J Spinal Cord Med ; 36(3): 207-12, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23809590

RESUMEN

OBJECTIVE: Patients with spinal cord injury (SCI) typically have difficulty with constipation. Some undergo surgery for bowel management. We predicted that SCI patients would have higher mortality and/or morbidity rates following such surgery than neurally intact patients receiving the same procedures. We sought to evaluate this using a large population-based data set. METHODS: Patients receiving care at Department of Veterans Affairs Medical Centers (DVAMCs) with computer codes for SCI and constipation who later underwent colectomy, colostomy, or ileostomy during fiscal years 1993-2002 were identified. Charts were requested from the VAMCs where the surgery had been performed and a retrospective chart review of these charts was done. We collected data on patient demographics, six specific pre-operative co-morbidities, surgical complications, and post-operative mortality. Comparisons were made to current literature evaluating a population receiving total abdominal colectomy and ileorectal anastomosis for constipation but not selected for SCI. RESULTS: Of 299 patients identified by computer search, 43 (14%) had codes for SCI and 10 of 43 (24%) met our inclusion criteria. All were symptomatic and had received appropriate medical management. Co-morbid conditions were present in 9 of 10 patients (90%). There were no deaths within 30 days. The complication rate was zero. The mean post-operative length of stay was 17 days. CONCLUSIONS: Patients with SCI comprise about 14% of the population who receive surgery for severe constipation in the Department of Veterans Affairs system. The mortality and morbidity rates in these patients are similar to those reported in other constipated patients who have surgery for intractable constipation. Our data suggest that stoma formation ± bowel resection in patients with SCI is a safe and effective treatment for chronic constipation.


Asunto(s)
Estreñimiento/etiología , Estreñimiento/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/mortalidad , Traumatismos de la Médula Espinal/complicaciones , Estreñimiento/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Intestino Neurogénico/etiología , Intestino Neurogénico/mortalidad , Intestino Neurogénico/cirugía , Traumatismos de la Médula Espinal/mortalidad , Veteranos
19.
Addiction ; 118(8): 1540-1548, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36905290

RESUMEN

BACKGROUND AND AIMS: The Opioid Use Disorder (OUD) Cascade of Care is a public health model that has been used to measure population-level OUD risk, treatment engagement, retention, service and outcome indicators. However, no studies have examined its relevance for American Indian and Alaska Native (AI/AN) communities. Thus, we aimed to understand (1) the utility of existing stages and (2) the relative 'fit' of the OUD Cascade of Care from a tribal perspective. DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS: Qualitative analysis of in-depth interviews with 20 individuals who were knowledgeable regarding the treatment of OUD in an Anishinaabe tribal setting in Minnesota, USA. Community member roles included clinicians, peer support specialists and cultural practitioners, among others. Thematic analysis was used to analyze the data. FINDINGS: Participants identified the key transition points of prevention, assessment, inpatient/outpatient pathways and recovery as relevant to their community. They re-imagined an Aanji'bide (Changing our Paths) model of opioid recovery and change that was non-linear; included developmental stage and individual pathways; and demonstrated resilience through connection to culture/spirituality, community and others. CONCLUSIONS: Community members living/working in a rural tribal nation in Minnesota, USA identified non-linearity and cultural connection as key elements to include in an Anishinaabe-centered model of opioid recovery and change.


Asunto(s)
Asistencia Sanitaria Culturalmente Competente , Indígenas Norteamericanos , Trastornos Relacionados con Opioides , Atención Dirigida al Paciente , Humanos , Minnesota , Trastornos Relacionados con Opioides/diagnóstico , Trastornos Relacionados con Opioides/etnología , Trastornos Relacionados con Opioides/terapia , Estados Unidos , Asistencia Sanitaria Culturalmente Competente/etnología , Asistencia Sanitaria Culturalmente Competente/métodos , Población Rural , Atención Dirigida al Paciente/métodos
20.
J Neurosci ; 31(1): 322-30, 2011 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-21209218

RESUMEN

Many forms of learning, including songbird vocal learning, rely on the brain's ability to use pre-motor variation and sensory feedback to guide behavior toward a specific target or goal. In the vocal control system of zebra finches (Taeniopygia guttata) the pre-motor mechanisms of vocal variation are thought to be vested primarily in a neural pathway that includes the basal ganglia. A second circuit that includes avian analogues of mammalian pre-motor and motor cortex (the vocal motor pathway) generates the patterned structure of learned adult song. Here, we tested the ability of the basal ganglia pathway to generate pre-motor vocal variation within the spectral and temporal dimensions of zebra finch song structure. In adult birds, ablation of the basal ganglia pathway significantly reduced the spectral and temporal dispersion of individual song syllables, with the exception of syllable pitch, where the reduction was not statistically significant when compared against surgical controls. We found a similar pattern of results using longitudinal comparisons (juvenile vs adult) to isolate the contribution of the basal ganglia pathway to spectral dispersion in populations of developing song syllables--variation in syllable pitch was significantly smaller than in all other measured spectral features. The results indicate that pre-motor variation generated by the basal ganglia pathway may be sufficient to adjust vocal output toward highly acoustically dispersed targets of imitation, but suggest that complete acquisition of the pronounced variation in syllable pitch that characterizes adult song will necessitate a gradual developmental interaction between the basal ganglia and vocal motor pathways.


Asunto(s)
Vías Auditivas/fisiología , Percepción Auditiva/fisiología , Ganglios Basales/fisiología , Aprendizaje/fisiología , Vocalización Animal/fisiología , Estimulación Acústica/métodos , Factores de Edad , Análisis de Varianza , Animales , Ganglios Basales/lesiones , Conducta Animal , Pinzones , Masculino , Prosencéfalo/fisiología , Psicoacústica , Distribución Aleatoria , Análisis Espectral , Estadísticas no Paramétricas
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