The LTAR cropland common experiment in the Lower Mississippi River Basin.

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.

Comparative analysis of three next-generation sequencing techniques to measure nosZ gene abundance in Missouri claypan soils.

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.

Community member perspectives on adapting the cascade of care for opioid use disorder for a tribal nation in the United States.

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.

Network dynamics underlie learning and performance of birdsong.

Understanding the sensorimotor control of the endless variety of human speech patterns stands as one of the apex problems in neuroscience. The capacity to learn - through imitation - to rapidly sequence vocal sounds in meaningful patterns is clearly one of the most derived of human behavioral traits. Selection pressure produced an analogous capacity in numerous species of vocal-learning birds, and due to an increasing appreciation for the cognitive and computational flexibility of avian cortex and basal ganglia, a general understanding of the forebrain network that supports the learning and production of birdsong is beginning to emerge. Here, we review recent advances in experimental studies of the zebra finch (Taeniopygia guttata), which offer new insights into the network dynamics that support this surprising analogue of human speech learning and production.

Experience-Dependent Intrinsic Plasticity During Auditory Learning.

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.

Female zebra finches do not sing yet share neural pathways necessary for singing in males.

Adult female zebra finches (Taeniopygia guttata), which do not produce learned songs, have long been thought to possess only vestiges of the forebrain network that supports learned song in males. This view ostensibly explains why females do not sing-many of the neural populations and pathways that make up the male song control network appear rudimentary or even missing in females. For example, classic studies of vocal-premotor cortex (HVC, acronym is name) in male zebra finches identified prominent efferent pathways from HVC to vocal-motor cortex (RA, robust nucleus of the arcopallium) and from HVC to the avian basal ganglia (Area X). In females, by comparison, the efferent targets of HVC were thought to be only partially innervated by HVC axons (RA) or absent (Area X). Here, using a novel visually guided surgical approach to target tracer injections with precision, we mapped the extrinsic connectivity of the adult female HVC. We find that female HVC shows a mostly male-typical pattern of afferent and efferent connectivity, including robust HVC innervation of RA and Area X. As noted by earlier investigators, we find large sex differences in the volume of many regions that control male singing (male > female). However, sex differences in volume were diminished in regions that convey ascending afferent input to HVC. Our findings do not support a vestigial interpretation of the song control network in females. Instead, our findings support the emerging view that the song control network may have an altogether different function in nonsinging females.

Interhemispheric dominance switching in a neural network model for birdsong.

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.

Development of the LYVE-1 gene with an acidic-amino-acid-rich (AAAR) domain in evolution is associated with acquisition of lymph nodes and efficient adaptive immunity.

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.

Neuronal Intrinsic Physiology Changes During Development of a Learned Behavior.

Juvenile male zebra finches learn their songs over distinct auditory and sensorimotor stages, the former requiring exposure to an adult tutor song pattern. The cortical premotor nucleus HVC (acronym is name) plays a necessary role in both learning stages, as well as the production of adult song. Consistent with neural network models where synaptic plasticity mediates developmental forms of learning, exposure to tutor song drives changes in the turnover, density, and morphology of HVC synapses during vocal development. A network's output, however, is also influenced by the intrinsic properties (e.g., ion channels) of the component neurons, which could change over development. Here, we use patch clamp recordings to show cell-type-specific changes in the intrinsic physiology of HVC projection neurons as a function of vocal development. Developmental changes in HVC neurons that project to the basal ganglia include an increased voltage sag response to hyperpolarizing currents and an increased rebound depolarization following hyperpolarization. Developmental changes in HVC neurons that project to vocal-motor cortex include a decreased resting membrane potential and an increased spike amplitude. HVC interneurons, however, show a relatively stable range of intrinsic features across vocal development. We used mathematical models to deduce possible changes in ionic currents that underlie the physiological changes and to show that the magnitude of the observed changes could alter HVC circuit function. The results demonstrate developmental plasticity in the intrinsic physiology of HVC projection neurons and suggest that intrinsic plasticity may have a role in the process of song learning.

A distributed neural network model for the distinct roles of medial and lateral HVC in zebra finch song production.

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.

Orthogonal topography in the parallel input architecture of songbird HVC.

Neural activity within the cortical premotor nucleus HVC (acronym is name) encodes the learned songs of adult male zebra finches (Taeniopygia guttata). HVC activity is driven and/or modulated by a group of five afferent nuclei (the Medial Magnocellular nucleus of the Anterior Nidopallium, MMAN; Nucleus Interface, NIf; nucleus Avalanche, Av; the Robust nucleus of the Arcopallium, RA; the Uvaeform nucleus, Uva). While earlier evidence suggested that HVC receives a uniformly distributed and nontopographic pattern of afferent input, recent evidence suggests this view is incorrect (Basista et al., ). Here, we used a double-labeling strategy (varying both the distance between and the axial orientation of dual tracer injections into HVC) to reveal a massively parallel and in some cases topographic pattern of afferent input. Afferent neurons target only one rostral or caudal location within medial or lateral HVC, and each HVC location receives convergent input from each afferent nucleus in parallel. Quantifying the distributions of single-labeled cells revealed an orthogonal topography in the organization of afferent input from MMAN and NIf, two cortical nuclei necessary for song learning. MMAN input is organized across the lateral-medial axis whereas NIf input is organized across the rostral-caudal axis. To the extent that HVC activity is influenced by afferent input during the learning, perception, or production of song, functional models of HVC activity may need revision to account for the parallel input architecture of HVC, along with the orthogonal input topography of MMAN and NIf.

7-Dehydrocholesterol (7-DHC), But Not Cholesterol, Causes Suppression of Canonical TGF-ß Signaling and Is Likely Involved in the Development of Atherosclerotic Cardiovascular Disease (ASCVD).

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.

Effectiveness of Pharmacist and Physician Collaboration in the Treatment of Type 2 Diabetes Mellitus With Severe Insulin Resistance Using U-500 Insulin.

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.

Optimal Colostomy Placement in Spinal Cord Injury Patients.

Barring unusual circumstances, sigmoid colostomy is the optimal technique for management of defecation in spinal cord injury (SCI) patients. We sought to provide evidence that a sigmoid colostomy is not difficult to perform in SCI patients and has better long-term results. The St. Louis Department of Veterans Affairs has a Commission on Accreditation of Rehabilitation Facilities (CARF)-approved SCI Unit. We reviewed the operative notes on all SCI patients who received a colostomy for fecal management by three ASCRS-certified colorectal surgeons at the St. Louis Department of Veterans Affairs from January 1, 2007 to November 26, 2012. There were 27 operations for which the recorded indication for surgery suggested that the primary disorder was SCI. Fourteen had traumatic SCI of the thoracic and/or lumbar spine and were evaluable. Of these 14 patients, 12 had laparoscopic sigmoid colostomy and two had open sigmoid colostomy. We encountered one evaluable patient with a remarkably large amount of retroperitoneal bony debris who successfully underwent laparoscopic sigmoid colostomy. In conclusion, sigmoid colostomy is the consensus optimal procedure for fecal management in SCI patients. Laparoscopic procedures are preferred. Care providers should specify sigmoid colostomy when contacting a surgeon.

Ethanol Enhances TGF-ß Activity by Recruiting TGF-ß Receptors From Intracellular Vesicles/Lipid Rafts/Caveolae to Non-Lipid Raft Microdomains.

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.

Adjuvant radiation therapy for breast cancer in patients with schizophrenia.

BACKGROUND: Schizophrenia affects approximately 1% of subjects in all populations studied thus far. We sought to evaluate how patients with schizophrenia who are later diagnosed with breast cancer fare when adjuvant radiation therapy (ART) is clinically indicated. METHODS: We searched patient treatment file, the national inpatient computer database of the Department of Veterans Affairs, to identify patients with schizophrenia who subsequently developed breast cancer. RESULTS: Forty patients had schizophrenia, who later developed breast cancer and were candidates for ART, according to well-established guidelines. Of the 40 patients who were considered candidates for ART, we found data about the decision to offer ART in 35; only 22 (63%) were offered ART and 5 of those 22 (23%) refused it. CONCLUSIONS: Patients with schizophrenia and breast cancer often do not understand the nature of their illnesses well. They often do not comply with recommended standard therapies such as ART. Treatment strategies that rely on ART are likely to be met with noncompliance. Breast-preserving treatment plans may be impractical. Initial radical surgery without ART may be preferable.

Independent premotor encoding of the sequence and structure of birdsong in avian cortex.

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.

Intensity of follow-up after breast cancer surgery: low versus high?

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.

Disconnection of a basal ganglia circuit in juvenile songbirds attenuates the spectral differentiation of song syllables.

Similar to language acquisition by human infants, juvenile male zebra finches (Taeniopygia guttata) imitate an adult (tutor) song by transitioning from repetitive production of one or two undifferentiated protosyllables to the sequential production of a larger and spectrally heterogeneous set of syllables. The primary motor region that controls learned song is driven by a confluence of input from two premotor pathways: a posterior pathway that encodes the adult song syllables and an anterior pathway that includes a basal ganglia (BG)-thalamo-cortical circuit. Similar to mammalian motor-learning systems, the songbird BG circuit is thought to be necessary for shaping juvenile vocal behaviour (undifferentiated protosyllables) toward specific targets (the tutor's song syllables). Here, we tested the hypothesis that anterior pathway activity contributes to the process of protosyllable differentiation. Bilateral ablation of lateral magnocellular nucleus of the anterior nidopallium (LMAN) was used to disconnect BG circuitry at ages before protosyllable production and differentiation. Comparison to surgical controls revealed that protosyllables fail to differentiate in birds that received juvenile LMAN ablation--the adult songs of birds with >80% bilateral LMAN ablation consisted of only one or two syllables produced with the repetitive form and spectral structure that characterizes undifferentiated protosyllables in normal juveniles. Our findings support a role for BG circuitry in shaping juvenile vocal behaviour toward the acoustic structure of the tutor song and suggest that posterior pathway function remains in an immature "default" state when developmental interaction with the anterior pathway is reduced or eliminated.

Surgery for constipation in patients with prior spinal cord injury: the Department of Veterans Affairs experience.

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.