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1.
BMC Immunol ; 25(1): 24, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38689233

RESUMEN

BACKGROUND: Bacillus Calmette-Guérin (BCG) vaccination has off-target protective effects against infections unrelated to tuberculosis. Among these, murine and human studies suggest that BCG vaccination may protect against malaria. We investigated whether BCG vaccination influences neonatal in vitro cytokine responses to Plasmodium falciparum. Blood samples were collected from 108 participants in the Melbourne Infant Study BCG for Allergy and Infection Reduction (MIS BAIR) randomised controlled trial (Clinical trials registration NCT01906853, registered July 2013), seven days after randomisation to neonatal BCG (n = 66) or no BCG vaccination (BCG-naïve, n = 42). In vitro cytokine responses were measured following stimulation with P. falciparum-infected erythrocytes (PfIE) or E. coli. RESULTS: No difference in the measured cytokines were observed between BCG-vaccinated and BCG-naïve neonates following stimulation with PfIE or E. coli. However, age at which blood was sampled was independently associated with altered cytokine responses to PfIE. Being male was also independently associated with increased TNF-a responses to both PfIE and E. coli. CONCLUSION: These findings do not support a role for BCG vaccination in influencing in vitro neonatal cytokine responses to P. falciparum. Older neonates are more likely to develop P. falciparum-induced IFN-γ and IFN-γ-inducible chemokine responses implicated in early protection against malaria and malaria pathogenesis.


Asunto(s)
Vacuna BCG , Citocinas , Malaria Falciparum , Plasmodium falciparum , Vacunación , Humanos , Plasmodium falciparum/inmunología , Vacuna BCG/inmunología , Recién Nacido , Femenino , Malaria Falciparum/inmunología , Malaria Falciparum/prevención & control , Citocinas/metabolismo , Masculino , Eritrocitos/inmunología , Eritrocitos/parasitología , Escherichia coli/inmunología , Lactante
2.
Parkinsonism Relat Disord ; 120: 106007, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38241953

RESUMEN

INTRODUCTION: Palliative care focuses on improving patient and family quality of life by managing symptoms, psychosocial issues and spiritual concerns. Huntington's disease is a progressive neurodegenerative disorder with no current disease modifying therapy. Although the palliative care model has been postulated to be an integral part of HD care, there are gaps in knowledge about how this care should be implemented. This study aims to identify perceptions of palliative care in Huntington's Disease (HD), palliative care needs of people living with HD, and at what point they feel they would benefit from these resources. METHODS: Participants volunteered from a large academic institution patient base to be involved in semi structured interviews that explored patient and caregiver experience surrounding their diagnosis, disease management, quality of life, and areas for improvement. Inclusion criteria for participants was a diagnosis of Huntington's disease and/or a self-identified caregiver of a person living with the disease. RESULTS: A total of 12 independent patients, three independent caregivers, and five dyads completed the interviews. Themes identified included needs that would provide patient and caregiver centered treatment, current gaps in care, an openness and desire for palliative care, and knowledge about the desired timing of palliative care in treatment plans. CONCLUSION: People living with HD and caregivers of people with HD most desire access to treatment that would focus on symptom management, availability of social resources, advanced care planning and spiritual wellbeing. The preferred timing of this intervention for most individuals would be at the onset of symptoms.


Asunto(s)
Enfermedad de Huntington , Cuidados Paliativos , Humanos , Enfermedad de Huntington/terapia , Enfermedad de Huntington/psicología , Calidad de Vida , Investigación Cualitativa , Cuidadores/psicología
3.
J Affect Disord ; 347: 249-261, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-37995926

RESUMEN

BACKGROUND: Anhedonia is a transdiagnostic symptom of severe mental illness (SMI) and emerges during adolescence. Possible subphenotypes and neural mechanisms of anhedonia in adolescents at risk for SMI are understudied. METHODS: Adolescents at familial risk for SMI (N = 81) completed anhedonia (e.g., consummatory, anticipatory, social), demographic, and clinical measures and one year prior, a subsample (N = 46) completed fMRI scanning during a monetary reward task. Profiles were identified using k-means clustering of anhedonia type and differences in demographics, suicidal ideation, impulsivity, and emotional processes were examined. Moderation analyses were conducted to investigate whether levels of brain activation of reward regions moderated the relationships between anhedonia type and behaviors. RESULTS: Two-clusters emerged: a high anhedonia profile (high-anhedonia), characterized by high levels of all types of anhedonia, (N = 32) and a low anhedonia profile (low-anhedonia), characterized by low levels of anhedonia types (N = 49). Adolescents in the high-anhedonia profile reported more suicidal ideation and negative affect, and less positive affect and desire for emotional closeness than low-anhedonia profile. Furthermore, more suicidal ideation, less positive affect, and less desire for emotional closeness differentiated the familial high-risk, high-anhedonia profile adolescents from the familial high-risk, low-anhedonia profile adolescents. Across anhedonia profiles, moderation analyses revealed that adolescents with high dmPFC neural activation in response to reward had positive relationships between social, anticipatory, and consummatory anhedonia and suicidal ideation. LIMITATIONS: Small subsample with fMRI data. CONCLUSION: Profiles of anhedonia emerge transdiagnostically and vary on clinical features. Anhedonia severity and activation in frontostriatal reward areas have value for clinically important outcomes such as suicidal ideation.


Asunto(s)
Anhedonia , Trastornos Mentales , Humanos , Adolescente , Anhedonia/fisiología , Trastornos Mentales/diagnóstico por imagen , Encéfalo , Análisis por Conglomerados , Predisposición Genética a la Enfermedad
4.
J Affect Disord ; 319: 325-328, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36087789

RESUMEN

INTRODUCTION: Identification of neural markers associated with risk for manic symptoms is an important challenge for neuropsychiatric research. Previous work has highlighted the association between predisposition for mania/hypomania and elevated reward sensitivity. Elevated activity in the left ventrolateral prefrontal cortex (L vlPFC) during reward expectancy (RE) is associated with measures predictive of risk for manic/hypomanic symptoms. However, no studies have examined this relationship longitudinally. The goal of this study was to identify a neural marker associated with longitudinal risk for manic/hypomanic symptoms. METHODS: We used a card guessing functional magnetic resonance imaging (fMRI) paradigm to examine RE-related L vlPFC activity. One hundred and three young adults who were either healthy or experiencing psychological distress completed a single baseline fMRI scan and self-report measures of manic/hypomanic symptoms. Self-report measures were repeated up to two follow up visits over one year. RESULTS: We identified a significant positive relationship between baseline RE-related L vlPFC activity and MOODS Manic Domain scores up to one-year post scan. This relationship was specific to manic symptoms and was not present for MOODS depression-related domains. LIMITATIONS: This study was not designed to predict conversion to bipolar disorder, but rather the more proximal construct of lifetime risk for mania/hypomania. CONCLUSIONS: RE-related L vlPFC activity may serve as an important marker of risk for future manic/hypomanic symptoms and may also be a potential target for intervention.


Asunto(s)
Trastorno Bipolar , Manía , Adulto Joven , Humanos , Recompensa , Trastorno Bipolar/diagnóstico , Corteza Cerebral , Imagen por Resonancia Magnética
5.
Environ Microbiol ; 24(8): 3390-3404, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35641308

RESUMEN

Fine root endophyte mycorrhizal fungi in the Endogonales (Mucoromycota arbuscular mycorrhizal fungi, M-AMF) are now recognized as at least as important globally as Glomeromycota AMF (G-AMF), yet little is known about the environmental factors which influence M-AMF diversity and colonization, partly because they typically only co-colonize plants with G-AMF. Wild populations of Lycopodiella inundata predominantly form mycorrhizas with M-AMF and therefore allow focussed study of M-AMF environmental drivers. Using microscopic examination and DNA sequencing we measured M-AMF colonization and diversity over three consecutive seasons and modelled interactions between these response variables and environmental data. Significant relationships were found between M-AMF colonization and soil S, P, C:N ratio, electrical conductivity, and the previously overlooked micronutrient Mn. Estimated N deposition was negatively related to M-AMF colonization. Thirty-nine Endogonales Operational Taxonomic Units (OTUs) were identified in L. inundata roots, a greater diversity than previously recognized in this plant. Endogonales OTU richness correlated negatively with soil C:N while community composition was mostly influenced by soil P. This study provides first evidence that M-AMF have distinct ecological preferences in response to edaphic variables also related to air pollution. Future studies require site-level atmospheric pollution monitoring to guide critical load policy for mycorrhizal fungi in heathlands and grasslands.


Asunto(s)
Glomeromycota , Micorrizas , Contaminación Ambiental , Hongos/fisiología , Glomeromycota/genética , Micorrizas/genética , Nutrientes , Raíces de Plantas/microbiología , Plantas , Suelo , Microbiología del Suelo
6.
J Orthop Res ; 39(6): 1217-1226, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32333606

RESUMEN

In vitro biomechanical studies of the osteoligamentous spine are widely used to characterize normal biomechanics, identify injury mechanisms, and assess the effects of degeneration and surgical instrumentation on spine mechanics. The objective of this study was to determine how well four standards in vitro loading paradigms replicate in vivo kinematics with regards to the instantaneous center of rotation and arthrokinematics in relation to disc deformation. In vivo data were previously collected from 20 asymptomatic participants (45.5 ± 5.8 years) who performed full range of motion neck flexion-extension (FE) within a biplane x-ray system. Intervertebral kinematics were determined with sub-millimeter precision using a validated model-based tracking process. Ten cadaveric spines (51.8 ± 7.3 years) were tested in FE within a robotic testing system. Each specimen was tested under four loading conditions: pure moment, axial loading, follower loading, and combined loading. The in vivo and in vitro bone motion data were directly compared. The average in vitro instant center of rotation was significantly more anterior in all four loading paradigms for all levels. In general, the anterior and posterior disc heights were larger in the in vitro models than in vivo. However, after adjusting for gender, the observed differences in disc height were not statistically significant. This data suggests that in vitro biomechanical testing alone may fail to replicate in vivo conditions, with significant implications for novel motion preservation devices such as cervical disc arthroplasty implants.


Asunto(s)
Vértebras Cervicales/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Disco Intervertebral/fisiología , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Rotación
7.
Rev Sci Instrum ; 91(8): 083104, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32872970

RESUMEN

Ion Doppler Spectroscopy (IDS) is a diagnostic technique that measures plasma ion temperature and velocity without perturbing the plasma with a physical probe. The ZaP-HD Flow Z-Pinch Experiment at the University of Washington uses this technique to resolve radial temperature and velocity profiles of a Z-pinch plasma. The pinch lifetime is ∼100 µs; therefore, diagnostics capable of sub-microsecond resolution are required to measure the evolution of temperature and velocity profiles. The previous IDS diagnostic system was only capable of collecting a single measurement during a plasma pulse. An improved system has been developed to measure the radially resolved ion temperature and velocity for the entire Z-pinch lifetime. A Kirana 05M ultra-fast framing camera and Specialized Imaging lens ultraviolet intensifier are used to record up to 100 spectra per plasma pulse. The temperature is computed from Doppler broadening of the carbon-III (229.687 nm) impurity ion radiation, and the velocity is computed from the Doppler shift of carbon-III. Measurements are able to resolve the evolution of the ion temperature and velocity over the course of a plasma pulse. The diagnostic has significantly reduced the number of pulses required and provides a more coherent measurement of plasma dynamics than the previous system.

8.
Phys Rev Lett ; 122(13): 135001, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-31012637

RESUMEN

The sheared-flow stabilized Z pinch has demonstrated long-lived plasmas with fusion-relevant parameters. We present the first experimental results demonstrating sustained, quasi-steady-state neutron production from the fusion Z-pinch experiment, operated with a mixture of 20% deuterium/80% hydrogen by pressure. Neutron emissions lasting approximately 5 µs are reproducibly observed with pinch currents of approximately 200 kA during an approximately 16 µs period of plasma quiescence. The average neutron yield is estimated to be (1.25±0.45)×10^{5} neutrons/pulse and scales with the square of the deuterium concentration. Coincident with the neutron signal, plasma temperatures of 1-2 keV and densities of approximately 10^{17} cm^{-3} with 0.3 cm pinch radii are measured with fully integrated diagnostics.

9.
Transl Psychiatry ; 7(4): e1096, 2017 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-28418404

RESUMEN

High trait impulsive sensation seeking (ISS) is common in 18-25-year olds, and is associated with risky decision-making and deleterious outcomes. We examined relationships among: activity in reward regions previously associated with ISS during an ISS-relevant context, uncertain reward expectancy (RE), using fMRI; ISS impulsivity and sensation-seeking subcomponents; and risky decision-making in 100, transdiagnostically recruited 18-25-year olds. ISS, anhedonia, anxiety, depression and mania were measured using self-report scales; clinician-administered scales also assessed the latter four. A post-scan risky decision-making task measured 'risky' (possible win/loss/mixed/neutral) fMRI-task versus 'sure thing' stimuli. 'Bias' reflected risky over safe choices. Uncertain RE-related activity in left ventrolateral prefrontal cortex and bilateral ventral striatum was positively associated with an ISS composite score, comprising impulsivity and sensation-seeking-fun-seeking subcomponents (ISSc; P⩽0.001). Bias positively associated with sensation seeking-experience seeking (ES; P=0.003). This relationship was moderated by ISSc (P=0.009): it was evident only in high ISSc individuals. Whole-brain analyses showed a positive relationship between: uncertain RE-related left ventrolateral prefrontal cortical activity and ISSc; uncertain RE-related visual attention and motor preparation neural network activity and ES; and uncertain RE-related dorsal anterior cingulate cortical activity and bias, specifically in high ISSc participants (all ps<0.05, peak-level, family-wise error corrected). We identify an indirect pathway linking greater levels of uncertain RE-related activity in reward, visual attention and motor networks with greater risky decision-making, via positive relationships with impulsivity, fun seeking and ES. These objective neural markers of high ISS can guide new treatment developments for young adults with high levels of this debilitating personality trait.


Asunto(s)
Nivel de Alerta/fisiología , Encéfalo/fisiopatología , Toma de Decisiones/fisiología , Conducta Exploratoria/fisiología , Red Nerviosa/fisiología , Recompensa , Asunción de Riesgos , Adolescente , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
10.
Psychol Med ; 47(8): 1357-1369, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27998326

RESUMEN

BACKGROUND: Identifying youth who may engage in future substance use could facilitate early identification of substance use disorder vulnerability. We aimed to identify biomarkers that predicted future substance use in psychiatrically un-well youth. METHOD: LASSO regression for variable selection was used to predict substance use 24.3 months after neuroimaging assessment in 73 behaviorally and emotionally dysregulated youth aged 13.9 (s.d. = 2.0) years, 30 female, from three clinical sites in the Longitudinal Assessment of Manic Symptoms (LAMS) study. Predictor variables included neural activity during a reward task, cortical thickness, and clinical and demographic variables. RESULTS: Future substance use was associated with higher left middle prefrontal cortex activity, lower left ventral anterior insula activity, thicker caudal anterior cingulate cortex, higher depression and lower mania scores, not using antipsychotic medication, more parental stress, older age. This combination of variables explained 60.4% of the variance in future substance use, and accurately classified 83.6%. CONCLUSIONS: These variables explained a large proportion of the variance, were useful classifiers of future substance use, and showed the value of combining multiple domains to provide a comprehensive understanding of substance use development. This may be a step toward identifying neural measures that can identify future substance use disorder risk, and act as targets for therapeutic interventions.


Asunto(s)
Conducta del Adolescente/fisiología , Síntomas Afectivos/fisiopatología , Corteza Cerebral , Depresión/fisiopatología , Problema de Conducta , Recompensa , Trastornos Relacionados con Sustancias/diagnóstico , Adolescente , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Corteza Cerebral/fisiopatología , Niño , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos Relacionados con Sustancias/diagnóstico por imagen , Trastornos Relacionados con Sustancias/patología , Trastornos Relacionados con Sustancias/fisiopatología
11.
Mol Psychiatry ; 21(9): 1194-201, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26903272

RESUMEN

Behavioral and emotional dysregulation in childhood may be understood as prodromal to adult psychopathology. Additionally, there is a critical need to identify biomarkers reflecting underlying neuropathological processes that predict clinical/behavioral outcomes in youth. We aimed to identify such biomarkers in youth with behavioral and emotional dysregulation in the Longitudinal Assessment of Manic Symptoms (LAMS) study. We examined neuroimaging measures of function and white matter in the whole brain using 80 youth aged 14.0 (s.d.=2.0) from three clinical sites. Linear regression using the LASSO (Least Absolute Shrinkage and Selection Operator) method for variable selection was used to predict severity of future behavioral and emotional dysregulation measured by the Parent General Behavior Inventory-10 Item Mania Scale (PGBI-10M)) at a mean of 14.2 months follow-up after neuroimaging assessment. Neuroimaging measures, together with near-scan PGBI-10M, a score of manic behaviors, depressive behaviors and sex, explained 28% of the variance in follow-up PGBI-10M. Neuroimaging measures alone, after accounting for other identified predictors, explained ~1/3 of the explained variance, in follow-up PGBI-10M. Specifically, greater bilateral cingulum length predicted lower PGBI-10M at follow-up. Greater functional connectivity in parietal-subcortical reward circuitry predicted greater PGBI-10M at follow-up. For the first time, data suggest that multimodal neuroimaging measures of underlying neuropathologic processes account for over a third of the explained variance in clinical outcome in a large sample of behaviorally and emotionally dysregulated youth. This may be an important first step toward identifying neurobiological measures with the potential to act as novel targets for early detection and future therapeutic interventions.


Asunto(s)
Síntomas Afectivos/fisiopatología , Sustancia Blanca/fisiopatología , Adolescente , Síntomas Afectivos/genética , Trastorno Bipolar/diagnóstico , Encéfalo/fisiopatología , Niño , Emociones/fisiología , Femenino , Predicción/métodos , Humanos , Estudios Longitudinales , Masculino , Padres/psicología , Escalas de Valoración Psiquiátrica , Recompensa , Resultado del Tratamiento
12.
J Anim Sci ; 93(1): 117-26, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25568362

RESUMEN

The use of genetic markers to aid in selection decisions to improve carcass and growth characteristics is of great interest to the beef industry. However, it is important to examine potential antagonistic interactions with fertility in cows before widespread application of marker-assisted selection. The objective of the current experiment was to examine the influence of 2 commercially available markers currently in use for improving carcass traits, the myostatin (MSTN) F94L and µ-calpain (CAPN1) 316 and 4751 polymorphisms, on heifer development and reproductive performance. In Exp. 1, beef heifers (n = 146) were evaluated for growth and reproductive traits over a 3-yr period to determine if these polymorphisms influenced reproductive performance. In Exp. 2, heifers representing the 2 homozygous genotypes for the MSTN F94L polymorphism were slaughtered on d 4 of the estrous cycle and reproductive tracts were collected for morphological examination. In Exp. 1, there was a tendency (P = 0.06) for birth BW to be affected by MSTN with the Leu allele increasing birth BW in an additive fashion. Additionally, MSTN significantly affected the proportion of pubertal heifers by the start of the breeding season (P < 0.05) with the Leu allele additively decreasing the proportion pubertal; however, this did not result in a delay in conception or a decrease in pregnancy rates during the first breeding season (P > 0.15). The GT haplotype of CAPN1, which was previously associated with decreased meat tenderness, was associated with an additive decrease in birth BW of the first calf born to these heifers (P < 0.05). In Exp. 2, there were no differences between the MSTN genotypes for gross or histological morphology of the anterior pituitary, uterus, or ovaries (P > 0.05). From these results, we concluded that the MSTN F94L and CAPN1 polymorphisms can be used to improve carcass traits without compromising fertility in beef heifers. The influence of these markers on cow performance and herd life remains to be determined. While the delay in puberty associated with the MSTN F94L polymorphism did not negatively impact reproductive performance in heifers, caution should be used when combining this marker with other markers for growth or carcass traits until the potential interactions are more clearly understood.


Asunto(s)
Peso al Nacer/fisiología , Calpaína/fisiología , Fertilidad/fisiología , Miostatina/fisiología , Fenotipo , Polimorfismo Genético/genética , Pubertad/fisiología , Animales , Peso al Nacer/genética , Cruzamiento/métodos , Calpaína/genética , Bovinos , Femenino , Fertilidad/genética , Marcadores Genéticos , Haplotipos/genética , Miostatina/genética , Embarazo , Pubertad/genética
13.
J Anim Sci ; 92(12): 5437-43, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25403194

RESUMEN

Replacing cows in the herd is second only to nutrition as the single greatest input cost in cow/calf beef production. The increased availability of cereal grains for feeding livestock has allowed replacement heifers to enter the production system at younger ages. Many heifer development programs feed to ensure heifers reach puberty before the time that they are mated to calve at 2 yr of age. Nutrition level during development has been associated with altered milk production and stayability. We hypothesized that heifers exposed to a lower nutrition level during the peripubertal period would have less methylation of the DNA in the mammary gland and ovarian cortex. We also hypothesized that the ovarian reserve would decrease in heifers fed for rapid growth compared to heifers fed for slow growth during puberty. At 257±1 d of age, heifers in the Stair-Step treatment (n=6) received 157 kcal ME/BW kg0.75 for 84 d and heifers in the Conventional treatment (n=6) were offered 228 kcal ME/BW kg0.75. At d 84, heifers were fed for an additional 83 d. Stair-Step heifers were offered 277 kcal ME/BW kg0.75, and heifers on the Conventional treatment received 228 kcal ME/BW kg0.75. Mammary weights (P=0.43), capillary area density (P=0.74), and capillary surface density (P=0.18) did not differ between treatments and neither did alveolar number (P=0.55) and alveolar density (P=0.49). Reproductive tract weights (P=0.69) and ovarian weight (P=0.68) and ovarian size (P>0.75) did not differ between treatments. In histological sections, Stair-Step heifers had more primordial follicles than Conventional heifers (P=0.02), but primary (P=0.59) and secondary (P=0.15) follicles did not differ. Global methylation of parenchymal tissue (P=0.82), mammary fat pad (P=0.45), and ovarian cortex (P=0.14) did not differ between treatments. Anterior pituitary weight did not differ between treatments (P=0.16). Our hypothesis that modifying peripubertal nutrition modifies global methylation of the mammary and ovary is not supported; however, our hypothesis that it modifies the ovarian reserve is supported.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Bovinos/crecimiento & desarrollo , Metilación de ADN/fisiología , Glándulas Mamarias Animales/crecimiento & desarrollo , Folículo Ovárico/crecimiento & desarrollo , Reproducción/fisiología , Maduración Sexual/fisiología , Factores de Edad , Análisis de Varianza , Animales , Peso Corporal/fisiología , Capilares/crecimiento & desarrollo , Ingestión de Energía/fisiología , Femenino , Técnicas Histológicas/veterinaria , Glándulas Mamarias Animales/química , Estado Nutricional/fisiología , Tamaño de los Órganos/fisiología , Folículo Ovárico/química , Reserva Ovárica/fisiología
14.
Psychol Med ; 43(10): 2215-25, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23286303

RESUMEN

BACKGROUND: Sleep loss produces abnormal increases in reward seeking but the mechanisms underlying this phenomenon are poorly understood. The present study examined the influence of one night of sleep deprivation on neural responses to a monetary reward task in a sample of late adolescents/young adults. METHOD: Using a within-subjects crossover design, 27 healthy, right-handed late adolescents/young adults (16 females, 11 males; mean age 23.1 years) underwent functional magnetic resonance imaging (fMRI) following a night of sleep deprivation and following a night of normal sleep. Participants' recent sleep history was monitored using actigraphy for 1 week prior to each sleep condition. RESULTS: Following sleep deprivation, participants exhibited increased activity in the ventral striatum (VS) and reduced deactivation in the medial prefrontal cortex (mPFC) during the winning of monetary reward, relative to the same task following normal sleep conditions. Shorter total sleep time over the five nights before the sleep-deprived testing condition was associated with reduced deactivation in the mPFC during reward. CONCLUSIONS: These findings support the hypothesis that sleep loss produces aberrant functioning in reward neural circuitry, increasing the salience of positively reinforcing stimuli. Aberrant reward functioning related to insufficient sleep may contribute to the development and maintenance of reward dysfunction-related disorders, such as compulsive gambling, eating, substance abuse and mood disorders.


Asunto(s)
Cuerpo Estriado/fisiopatología , Neuroimagen Funcional/métodos , Corteza Prefrontal/fisiopatología , Recompensa , Privación de Sueño/fisiopatología , Sueño/fisiología , Actigrafía , Adolescente , Adulto , Cuerpo Estriado/fisiología , Estudios Cruzados , Femenino , Neuroimagen Funcional/instrumentación , Humanos , Imagen por Resonancia Magnética , Masculino , Corteza Prefrontal/fisiología , Adulto Joven
15.
N Z Vet J ; 61(5): 292-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23227946

RESUMEN

AIM: To establish a method of gonad biopsy for ovarian tissue collection in the declining giant kokopu Galaxias argenteus (Gmelin 1789) as an alternative to lethal sampling in order to understand the species' reproductive biology. METHODS: Six female giant kokopu weighing between 200 and 350 g were caught from the wild in early December of 2009 and transferred to a holding facility (Department of Zoology, University of Otago, Dunedin) where they were kept under a simulated natural photo-thermal regime for 10 months. Fish were repeatedly biopsied for ovarian tissue at near-monthly intervals (mean number of days between biopsies = 33) until ovulation. RESULTS AND CONCLUSIONS: Ovarian samples were successfully collected from giant kokopu by biopsy for use in downstream analyses. Among a total of 23 biopsy events, a single death occurred when a two-layered suturing approach was used, highlighting the value of this method for study of the reproductive biology of valuable fish. CLINICAL RELEVANCE: This biopsy method may have implications for veterinary research on fish physiology, pathology, conservation and development, when repeated tissue samples need to be collected over a prolonged period of time or for general surgical manipulations on fish when accessing the coelom. Furthermore, this approach allows the implementation of a more powerful experimental design, as repeated measures reduces the variability of estimates due to the removal of inherent stage differences among individuals.


Asunto(s)
Peces/anatomía & histología , Ovario/anatomía & histología , Animales , Biopsia/métodos , Biopsia/veterinaria , Femenino , Peces/fisiología , Ovario/patología , Reproducción/fisiología
16.
Neuroscience ; 222: 333-42, 2012 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-22796077

RESUMEN

Brain-implantable electrodes such as those used in deep brain stimulation (DBS) have a promising future in end-stage Parkinson's disease therapy. However, there is considerable injury when electrodes penetrate brain tissue. For instance, broken blood vessels and glial scar formation may impede continual DBS or electrical recording from specific neurons. To begin addressing this key safety issue, we tested the therapeutic potential of resveratrol in reducing brain trauma caused by DBS-like surgery. Microinfusion of resveratrol (10 µM) directly applied to the sub-thalamic nucleus (STN) of the rat brain significantly minimized the formation of astrocytic gliosis in response to a 27-G precision-glide cannula implant. The therapeutic effects of resveratrol extended to the "kill zone", a boundary zone of about 100 µm comprising the cannula implant and surrounding neurons. We also found that resveratrol not only provided almost complete protection from mechanical injury to the brain, but that it also prevented undesirable motor deficits often seen in animals with lesions to the STN. Lastly, continuous infusion of resveratrol over a 4-week period led to the inhibition of pro-apoptotic, neurodegenerative and cell division cycle genes that may be associated with a reduction in astrocytic gliosis and glial scar formation within the STN. Taken together, these data suggest that application of resveratrol to the brain is an effective adjunct surgical procedure for minimizing acute neuronal injury when electrodes are implanted directly into the STN.


Asunto(s)
Antioxidantes/farmacología , Cateterismo/efectos adversos , Estimulación Encefálica Profunda/métodos , Electrodos Implantados/efectos adversos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores , Estilbenos/farmacología , Animales , Conducta Animal/fisiología , Estimulación Encefálica Profunda/efectos adversos , Dimetilsulfóxido/farmacología , Fluoresceínas , Colorantes Fluorescentes , Expresión Génica/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Masculino , Microinyecciones , Neuronas/patología , Compuestos Orgánicos , Reacción en Cadena de la Polimerasa , Equilibrio Postural/efectos de los fármacos , Ratas , Ratas Long-Evans , Resveratrol , Núcleo Subtalámico/patología
17.
Psychol Med ; 42(10): 2095-107, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22340187

RESUMEN

BACKGROUND: Depression is a leading cause of worldwide disability. Adolescence represents a key developmental window in which rates of this disorder increase markedly. Children with an anxiety disorder show a particular risk of developing depression during adolescence. METHOD: We present and review evidence for a developmental model that considers the intersection of two vulnerabilities relevant to the trajectory from anxiety to depression: difficulties in response to potential social evaluation and changes in reward processing at puberty. RESULTS: Evidence suggests that these vulnerabilities (a) have been associated with depression, (b) are likely to be problematic in many, but not all, anxious youth, and (c) may be exacerbated by maturational processes that occur around pubertal development in ways that can create a negative spiral into a depressive disorder. CONCLUSIONS: We discuss the possibility that early intervention strategies targeting key aspects of these vulnerabilities could alter the trajectory away from depression for many anxious youth.


Asunto(s)
Trastornos de Ansiedad/complicaciones , Trastornos de Ansiedad/psicología , Trastorno Depresivo/complicaciones , Trastorno Depresivo/psicología , Recompensa , Conducta Social , Adolescente , Niño , Femenino , Humanos , Masculino , Procesos Mentales , Factores de Riesgo , Autoimagen , Factores Sexuales
18.
Water Sci Technol ; 64(1): 22-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22053453

RESUMEN

Constructed wetlands (CWs) have been used to treat agricultural effluents with varying success especially with respect to their operational efficiency in winter and ability to retain phosphorus. Dirty water (DW) from dairy farms is a mixture of manure contaminated runoff and milk parlour washings with a highly polluting biochemical oxygen demand (BOD) < or =3000 mg/L. The initial performance a CW of a 1.2 ha horizontal flow CW consisting of five ponds in series designed to treat DW from a dairy unit was assessed over four years. Ponds were earth-lined and shallow (0.3 m) with a water residence time of 100 days and planted with five species of emergent macrophytes. In comparison to CW inflow, annual reductions were as follows: BOD 99%, P 95% and N 92.8%. Coliforms were reduced by a 10(-5) factor to natural levels. From May to October there was little CW discharge due to evaporative losses. Final effluent quality was poorest in February but remained within a regulatory effluent standard for BOD of 40 mg/L. If the CW had only four ponds (25% less surface area) effluent would have failed the BOD standard in three years.


Asunto(s)
Industria Lechera , Eliminación de Residuos Líquidos/métodos , Contaminación Química del Agua/análisis , Análisis de la Demanda Biológica de Oxígeno/normas , Enterobacteriaceae/aislamiento & purificación , Irlanda del Norte , Fósforo/análisis , Estanques/microbiología , Compuestos de Amonio Cuaternario/análisis , Estaciones del Año , Humedales
19.
Int J Androl ; 34(3): 212-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20497260

RESUMEN

The aim of this study was to determine the variability in total testosterone (TT) levels in healthy, non-obese ageing men with symptoms of androgen deficiency. Men aged ≥55 years were recruited from the community. Morning TT levels were measured on four occasions in a 12-month period. In all, 96 men aged 62.7 ± 6.8 years were studied. Geometric mean values (95% confidence interval) of TT levels for the cohort at each time point were 14.5 (13.4-15.7), 14.6 (13.5-15.8), 15.5 (14.4-16.8) and 15.0 (13.9-16.2) nmol/L. The maximum intra-individual difference in TT between the four samples was 4.1 nmol/L (interquartile range: 2.9-6.4). Using the average of two baseline TT values reduces the maximum difference to 2.3 nmol/L (1.0-3.8). Only 1 of 25 men with a documented TT <10 nmol/L at baseline had TT levels <10 nmol/L at all subsequent time points. A single TT level is a reliable predictor of repeat measures taken within a 12-month period for a cohort of healthy ageing men with symptoms of androgen deficiency. However, given that the diagnostic criteria for androgen deficiency are, in part, predicated upon serum TT, there is sufficient intra-subject variability to warrant repeat sampling to confirm an initial low TT level. Using an average of two baseline TT values reduces this variability.


Asunto(s)
Envejecimiento , Andrógenos/deficiencia , Testosterona/sangre , Testosterona/deficiencia , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Estudios de Cohortes , Humanos , Hipogonadismo , Masculino , Persona de Mediana Edad
20.
J Perinatol ; 30(8): 563-5, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20668465

RESUMEN

A term infant developed stridor, hoarse cry and respiratory distress after forceps-assisted delivery. Oral feeding resulted in aspiration. Flexible laryngoscopy showed a right-sided vocal cord paralysis (VCP). A magnetic resonance image (MRI) of the brain revealed an ovoid lesion in the posterior fossa impinging on the brainstem, which was considered to represent a subdural haematoma. Clinical signs of vocal cord palsy and the associated MRI changes resolved spontaneously by 6 weeks of age. Vocal cord palsy is a common cause of stridor in newborn infants, although in many cases it is considered idiopathic. This is the first report of vocal cord palsy associated with subdural haemorrhage after instrumental delivery, and may represent an important and previously unappreciated cause of VCP. This case highlights the importance of magnetic resonance brain imaging in those infants with VCP in whom the aetiology is uncertain.


Asunto(s)
Traumatismos del Nacimiento/diagnóstico , Extracción Obstétrica/efectos adversos , Hematoma Subdural/complicaciones , Hematoma Subdural/etiología , Parálisis de los Pliegues Vocales/etiología , Hematoma Subdural/diagnóstico , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Forceps Obstétrico/efectos adversos
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