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1.
Front Physiol ; 10: 990, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31427988

RESUMO

Caffeine is one of the few treatments available for infants with apnea of prematurity. As the recommended dosing regimen is not always sufficient to prevent apnea, higher doses may be prescribed. However, little is currently known about the impact of high-dose caffeine on the developing brain; thus, our aim was to investigate the consequences of a high-dose regimen on the immature ovine brain. High-dose caffeine (25 mg/kg caffeine base loading dose; 20 mg/kg daily maintenance dose; n = 9) or saline (n = 8) was administered to pregnant sheep from 105 to 118 days of gestation (DG; term = 147 days); this is broadly equivalent to 28-33 weeks of human gestation. At 119DG, the cerebral cortex, striatum, and cerebellum were assessed histologically and by immunohistochemistry. Compared with controls, caffeine-exposed fetuses showed (i) an increase in the density of Ctip2-positive layers V-VI projection neurons (p = 0.02), Tbr1-positive layers V-VI projection neurons (p < 0.0001), astrocytes (p = 0.03), and oligodendrocytes (p = 0.02) in the cerebral cortex, (ii) a decrease in the density of Cux1-positive layers II-IV projection neurons (p = 0.01) in the cerebral cortex, and (iii) a reduction in the area of Purkinje cell bodies in the cerebellum (p = 0.03). Comparing high-dose caffeine-exposed fetuses with controls, there was no difference (p > 0.05) in: (i) the volume of the cerebral cortex or striatum, (ii) the density of neurons (total and output projection neurons) in the striatum, (iii) dendritic spine density of layer V pyramidal cells, (iv) the density of cortical GABAergic interneurons, microglia, mature oligodendrocytes or proliferating cells, (v) total cerebellar area or dimensions of cerebellar layers, or (vi) the density of cerebellar white matter microglia, astrocytes, oligodendrocytes, or myelin. Daily exposure of the developing brain to high-dose caffeine affects some aspects of neuronal and glial development in the cerebral cortex and cerebellum in the short-term; the long-term structural and functional consequences of these alterations need to be investigated.

2.
Dev Neurosci ; 40(2): 162-174, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29763885

RESUMO

Intrauterine growth restriction (IUGR) can lead to adverse neurodevelopmental sequelae in postnatal life. However, the effects of IUGR on the cerebellum are still to be fully elucidated. A major determinant of growth and development of the cerebellum is proliferation and subsequent migration of cerebellar granule cells. Our objective was to determine whether IUGR, induced by chronic placental insufficiency (CPI) in guinea pigs, results in abnormal cerebellar development due to deficits suggestive of impaired granule cell proliferation and/or migration. CPI was induced by unilateral ligation of the uterine artery at mid-gestation, producing growth-restricted (GR) foetuses at 52 and 60 days of gestation (dg), and neonates at 1 week postnatal age (term approx. 67 dg). Controls were from sham-operated animals. In GR foetuses compared with controls at 52 dg, the external granular layer (EGL) width and internal granular layer (IGL) area were similar. In GR foetuses compared with controls at 60 dg: (a) the EGL width was greater (p < 0.005); (b) the IGL area was smaller (p < 0.005); (c) the density of Ki67-negative (postmitotic) granule cells in the EGL was greater (p < 0.01); (d) the somal area of Purkinje cells was reduced (p < 0.005), and (e) the linear density of Bergmann glia was similar. The EGL width in GR foetuses at 60 dg was comparable to that of 52 dg control and GR foetuses. The pattern of p27-immunoreactivity in the EGL was the inverse of Ki67-immunoreactivity at both foetal ages; there was no difference between control and GR foetuses at either age in the width of p27-immunoreactivity, or in the percentage of the EGL width that it occupied. In the molecular layer of GR neonates compared with controls there was an increase in the areal density of granule cells (p < 0.05) and in the percentage of migrating to total number of granule cells (p < 0.01) at 1 week but not at 60 dg (p > 0.05). Thus, we found no specific evidence that IUGR affects granule cell proliferation, but it alters the normal program of migration to the IGL and, in addition, the development of Purkinje cells. Such alterations will likely affect the development of appropriate circuitry and have implications for cerebellar function.


Assuntos
Cerebelo/embriologia , Cerebelo/patologia , Retardo do Crescimento Fetal/patologia , Neurônios/patologia , Animais , Feminino , Desenvolvimento Fetal , Feto , Cobaias , Neurogênese/fisiologia , Gravidez
3.
Front Cell Neurosci ; 11: 224, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804448

RESUMO

Erythropoietin (EPO) ameliorates inflammation-induced injury in cerebral white matter (WM). However, effects of inflammation on the cerebellum and neuroprotective effects of EPO are unknown. Our aims were to determine: (i) whether lipopolysaccharide (LPS)-induced intrauterine inflammation causes injury to, and/or impairs development of the cerebellum; and (ii) whether recombinant human EPO (rhEPO) mitigates these changes. At 107 ± 1 days gestational age (DGA; ~0.7 of term), fetal sheep received LPS (~0.9 µg/kg; i.v.) or an equivalent volume of saline, followed 1 h later with 5000 IU/kg rhEPO (i.v.) or an equivalent volume of saline (i.v.). This generated the following experimental groups: control (saline + saline; n = 6), LPS (LPS + saline, n = 8) and LPS + rhEPO (n = 8). At necropsy (116 ± 1 DGA; ~0.8 of term) the brain was perfusion-fixed and stained histologically (H&E) and immunostained to identify granule cells (Neuronal Nuclei, NeuN), granule cell proliferation (Ki67), Bergmann glia (glial fibrillary acidic protein, GFAP), astrogliosis (GFAP) and microgliosis (Iba-1). In comparison to controls, LPS fetuses had an increased density of Iba-1-positive microglia (p < 0.005) in the lobular WM; rhEPO prevented this increase (p < 0.05). The thickness of both the proliferative (Ki67-positive) and post-mitotic zones (Ki67-negative) of the EGL were increased in LPS-exposed fetuses compared to controls (p < 0.05), but were not different between controls and LPS + rhEPO fetuses. LPS also increased (p < 0.001) the density of granule cells (NeuN-positive) in the internal granule layer (IGL); rhEPO prevented the increase (p < 0.01). There was no difference between groups in the areas of the vermis (total cross-section), molecular layer (ML), IGL or WM, the density of NeuN-positive granule cells in the ML, the linear density of Bergmann glial fibers, the areal density or somal area of the Purkinje cells, the areal coverage of GFAP-positive astrocytes in the lobular and deep WM, the density of Iba-1-positive microglia in the deep WM or the density of apopotic cells in the cerebellum. LPS-induced intrauterine inflammation caused microgliosis and abnormal development of granule cells. rhEPO ameliorated these changes, suggesting that it is neuroprotective against LPS-induced inflammatory effects in the cerebellum.

4.
Can J Diabetes ; 41(2): 156-163, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27881298

RESUMO

OBJECTIVES: We involved patients and clinicians in Alberta, Canada, to establish research priorities in gestational diabetes mellitus (GDM), using an approach based on a model proposed by the James Lind Alliance (JLA). METHODS: We adapted the 4-step JLA process to engage women with GDM and clinicians to identify uncertainties about the management of GDM. Uncertainties were identified through a survey and a review of the clinical practice guidelines (CPG). Uncertainties were short-listed by a steering committee, followed by a 1-day facilitated workshop using a nominal group format and involving a similar number of patients and clinicians, who identified the top 10 research priorities. RESULTS: Across the various survey formats, 75 individuals submitted 389 uncertainties, the majority (44; 59%) coming from patients. We removed 9 questions as being out of scope or unclear, and 41 were identified on a review of CPG, resulting in a total of 421 uncertainties. After the priority setting process, the final top 10 research priorities included questions about a simpler, more accurate and convenient screening test; risk factors for GDM; improving postpartum diabetes screening; the impact of GDM on the future health of the children; lifestyle challenges and mental health issues; safety, effectiveness and/or impact of diet and/or medication treatments; appropriate timing for delivery; and how care is provided, organized or communicated. CONCLUSIONS: These top 10 research priorities were informed through a comprehensive and transparent process involving women who have experienced GDM as well as clinicians, and they may be regarded as research priorities for GDM.


Assuntos
Diabetes Gestacional , Participação do Paciente , Pesquisa , Feminino , Humanos , Médicos/psicologia , Guias de Prática Clínica como Assunto , Gravidez , Incerteza , Mulheres/psicologia
5.
Neuroimage ; 147: 841-851, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27725314

RESUMO

Investigating neonatal brain structure and function can offer valuable insights into behaviour and cognition in healthy and clinical populations; both at term age, and longitudinally in comparison with later time points. Parcellated brain atlases for adult populations are readily available, however warping infant data to adult template space is not ideal due to morphological and tissue differences between these groups. Several parcellated neonatal atlases have been developed, although there remains strong demand for manually parcellated ground truth data with detailed cortical definition. Additionally, compatibility with existing adult atlases is favourable for use in longitudinal investigations. We aimed to address these needs by replicating the widely-used Desikan-Killiany (2006) adult cortical atlas in neonates. We also aimed to extend brain coverage by complementing this cortical scheme with basal ganglia, thalamus, cerebellum and other subcortical segmentations. Thus, we have manually parcellated these areas volumetrically using high-resolution neonatal T2-weighted MRI scans, and initial automated and manually edited tissue classification, providing 100 regions in all. Linear and nonlinear T2-weighted structural templates were also generated. In this paper we provide manual parcellation protocols, and present the parcellated probability maps and structural templates together as the Melbourne Children's Regional Infant Brain (M-CRIB) atlas.


Assuntos
Atlas como Assunto , Encéfalo/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Feminino , Humanos , Recém-Nascido , Masculino
6.
BMC Health Serv Res ; 16: 316, 2016 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-27473755

RESUMO

BACKGROUND: Primary care reforms should be supported by high-quality evidence across the entire life cycle of research. Front-line healthcare providers play an increasing role in implementation research. We recently evaluated two interventions for people with type 2 diabetes (T2D) in partnership with four Primary Care Networks (PCNs) in Alberta, Canada. Here, we report healthcare professionals perspectives on participating in primary care implementation research. METHODS: Guided by the RE-AIM framework, we collected qualitative data before, during, and after both interventions. We conducted 34 in-person or telephone interviews with 17 individual PCN professionals. We used content analysis to identify emerging codes and concepts. RESULTS: Two major themes emerged from the data. First, healthcare managers were eager to conduct implementation research in a primary care setting. Second, regardless of willingness to conduct research, there were challenges to implementing experimental study designs for both interventions. PCN professionals presumed the interventions were better than usual care, expressed role conflict, and reported administrative burdens related to research participation. Perceptions of patient vulnerability and an obligation to intervene exacerbated these issues. CONCLUSIONS: Healthcare professionals with limited practical research experience might not foresee the challenges in implementing experimental study designs in primary care settings to generate high-quality evidence. These issues are intensified when healthcare professionals perceive target patient populations as vulnerable and in need of intervention based on the presenting illness. Possible solutions include further research training, involving healthcare professionals in study design development, and using non-clinical staff to conduct research activities, particularly among acutely unwell patient populations.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Pessoal de Saúde/psicologia , Pesquisa sobre Serviços de Saúde , Atenção Primária à Saúde/estatística & dados numéricos , Alberta , Atitude do Pessoal de Saúde , Atenção à Saúde/estatística & dados numéricos , Feminino , Pessoal de Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Pesquisa Qualitativa , Pesquisadores/psicologia
7.
Epilepsia ; 57(3): 484-94, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26786278

RESUMO

OBJECTIVE: Environmental exposures impart powerful effects on vulnerability to many brain diseases, including epilepsy. Mesial temporal lobe epilepsy (MTLE) is a common form of epilepsy, and it is often accompanied by neuropsychiatric comorbidities. This study tests the hypothesis that environmental enrichment (EE) confers antiepileptogenic, psychoprotective, and neuroprotective effects in the amygdala kindling model of MTLE, and explores potential neurobiologic mechanisms. METHODS: At weaning, male Wistar rats were allocated into either EE (large cages containing running wheels and toys; n = 43) or standard housing (SH; standard laboratory cages; n = 39) conditions. At P56, a bipolar electrode was implanted into the left amygdala, and rats underwent rapid amygdala kindling until experiencing five class V seizures (Racine scale, fully kindled). The elevated plus maze was used to assess anxiety. Postmortem histologic and molecular analyses investigated potential biologic mediators of effects. RESULTS: EE significantly delayed kindling epileptogenesis, with EE rats requiring a significantly greater number of kindling stimulations to reach a fully kindled state compared to SH rats (p < 0.05). EE and kindling both reduced anxiety (p < 0.05). Timm's staining revealed significant reductions in aberrant mossy fiber sprouting in EE rats (p < 0.05), and these effects of EE were accompanied by reduced expression of TrkB and CRH genes. SIGNIFICANCE: We identify beneficial effects of EE on vulnerability to limbic epileptogenesis and anxiety, and identify reduced pathologic neuroplasticity and plasticity-related gene expression as potential underlying mechanisms. Enhanced environmental stimulation represents a potential antiepileptogenic strategy that might also mitigate the common psychiatric comorbidities of MTLE.


Assuntos
Meio Ambiente , Epilepsia do Lobo Temporal/fisiopatologia , Abrigo para Animais , Plasticidade Neuronal , Tonsila do Cerebelo/fisiopatologia , Animais , Epilepsia do Lobo Temporal/patologia , Masculino , Plasticidade Neuronal/fisiologia , Ratos , Ratos Wistar , Fatores de Tempo
8.
Neuroinformatics ; 14(1): 69-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26381159

RESUMO

Volumetric and morphometric neuroimaging studies of the basal ganglia and thalamus in pediatric populations have utilized existing automated segmentation tools including FIRST (Functional Magnetic Resonance Imaging of the Brain's Integrated Registration and Segmentation Tool) and FreeSurfer. These segmentation packages, however, are mostly based on adult training data. Given that there are marked differences between the pediatric and adult brain, it is likely an age-specific segmentation technique will produce more accurate segmentation results. In this study, we describe a new automated segmentation technique for analysis of 7-year-old basal ganglia and thalamus, called Pediatric Subcortical Segmentation Technique (PSST). PSST consists of a probabilistic 7-year-old subcortical gray matter atlas (accumbens, caudate, pallidum, putamen and thalamus) combined with a customized segmentation pipeline using existing tools: ANTs (Advanced Normalization Tools) and SPM (Statistical Parametric Mapping). The segmentation accuracy of PSST in 7-year-old data was compared against FIRST and FreeSurfer, relative to manual segmentation as the ground truth, utilizing spatial overlap (Dice's coefficient), volume correlation (intraclass correlation coefficient, ICC) and limits of agreement (Bland-Altman plots). PSST achieved spatial overlap scores ≥90% and ICC scores ≥0.77 when compared with manual segmentation, for all structures except the accumbens. Compared with FIRST and FreeSurfer, PSST showed higher spatial overlap (p FDR < 0.05) and ICC scores, with less volumetric bias according to Bland-Altman plots. PSST is a customized segmentation pipeline with an age-specific atlas that accurately segments typical and atypical basal ganglia and thalami at age 7 years, and has the potential to be applied to other pediatric datasets.


Assuntos
Gânglios da Base/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Software , Tálamo/anatomia & histologia , Gânglios da Base/patologia , Criança , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/patologia , Humanos , Tálamo/patologia
9.
Can J Diabetes ; 39 Suppl 3: S113-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26243463

RESUMO

OBJECTIVE: To better understand the factors that affect care and outcomes in patients with type 2 diabetes, we developed the prospective Alberta's Caring for Diabetes (ABCD) cohort to collect, monitor and analyze data concerning several sociodemographic, behavioural, psychosocial, clinical and physiological factors that might influence diabetes care and outcomes. METHODS: We recruited 2040 individuals with type 2 diabetes through primary care networks, diabetes clinics and public advertisements. Data are being collected through self-administered surveys, including standardized measures of health status and self-care behaviours, and will eventually be linked to laboratory and administrative healthcare data and other novel databases. RESULTS: The average age of respondents was 64.4 years (SD=10.7); 45% were female, and 91% were white, with average duration of diabetes of 12 years (SD=10.0). The majority (76%) were physically inactive, and 10% were smokers. Most (88%) reported 2 or more chronic conditions in addition to diabetes, and 18% screened positively for depressive symptoms. The majority (92%) consented to future linkage with administrative data. Based on the literature and comparison with other surveys, the cohort appeared to fairly represent the general Alberta population with diabetes. CONCLUSIONS: The ABCD cohort will serve as the basis for explorations of the multidimensional and dynamic nature of diabetes care and complications. These data will contribute to broader scientific literature and will also help to identify local benchmarks and targets for intervention strategies, helping to guide policies and resource allocation related to the care and management of patients with type 2 diabetes in Alberta, Canada.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Adulto , Idoso , Alberta/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
10.
Can J Diabetes ; 39 Suppl 3: S83-91, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26227866

RESUMO

OBJECTIVE: We evaluated the implementation of an efficacious collaborative care model for patients with diabetes and depression in a controlled trial in 4 community-based primary care networks (PCNs) in Alberta, Canada. Similar to previous randomized trials, the nurse care manager-led TeamCare intervention demonstrated statistically significant improvements in depressive symptoms compared with usual care. We contextualized TeamCare's effectiveness by describing implementation fidelity at the organizational and patient levels. METHODS: We used the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework to evaluate TeamCare. Qualitative methods used to collect data regarding the RE-AIM dimensions of Implementation and Effectiveness included interviews with PCN staff and specialists (n=36), research team reflections (n=4) and systematic documentation. We used content analysis, and Nvivo 10 for data management. RESULTS: TeamCare was implemented as intended but with suboptimal fidelity. Deviations from the model included limited degrees of collaborative care practised within the PCNs, including varying physician participation, limited comfort in practising collaborative care and discontinuity of care managers. Despite suboptimal fidelity, respondents identified several implementation facilitators at the organizational level: training, ongoing implementation support, professional and personal qualities of the care manager and pre-existing relationships. Without knowledge of the effectiveness of the intervention in our controlled trial, respondents anticipated improved patient outcomes due to the main intervention components, including active patient follow up, specialist consultation and treat-to-target principles. CONCLUSIONS: Despite suboptimal implementation in Alberta's primary care context, TeamCare resulted in improved outcomes similar to those demonstrated in previous randomized trials. A stronger culture of collaborative care would likely have yielded greater implementation fidelity and possibly better outcomes.


Assuntos
Depressão , Diabetes Mellitus Tipo 2 , Pessoal de Saúde , Atenção Primária à Saúde/normas , Avaliação de Programas e Projetos de Saúde , Depressão/complicações , Depressão/terapia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Pessoal de Saúde/psicologia , Pessoal de Saúde/estatística & dados numéricos , Humanos , Modelos Teóricos , Pesquisa Qualitativa
11.
Can J Diabetes ; 39 Suppl 3: S100-12, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26145483

RESUMO

OBJECTIVE: Although there have been tremendous advances in diabetes care, including the development of efficacious interventions, there remain considerable challenges in translating these advances into practice. Four primary care networks (PCNs) in Alberta implemented 2 quality-improvement interventions focused on lifestyle and depression as part of the Alberta's Caring for Diabetes (ABCD) project. METHODS: We used the reach, effectiveness, adoption, implementation and maintenance (RE-AIM) framework to evaluate adoption of the quality-improvement interventions in the PCN setting. We undertook semistructured interviews with PCN staff (n=24); systematic documentation (e.g. field notes) and formal reflections by the research team (n=4). Content analysis was used to interrogate the data. RESULTS: The Ready? Set? Go! construct summarizes our findings well. We observed that the participating PCNs were in a favourable position to adopt the 2 interventions successfully. We implemented strategies to promote adoption (Ready), and respondents reported prioritization and willingness to initiate the interventions based on positive indicators (Set). Regardless, the interplay of organizational stability, leadership support, existing physician culture and organizational context influenced the overall degree of adoption of the interventions across the PCNs (Go). CONCLUSIONS: Our findings suggest that implementation of quality-improvement interventions into settings similar to the PCNs we studied will have the greatest likelihood of success when there is priority alignment, genuine and sustained leadership support and an innovative organizational culture. However, the stability of organizations may affect the degree to which staff can adopt quality-improvement interventions successfully, so organizational stability should be assessed on an ongoing basis.


Assuntos
Diabetes Mellitus/terapia , Atenção Primária à Saúde/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Melhoria de Qualidade/organização & administração , Humanos
12.
Can J Diabetes ; 39 Suppl 3: S77-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26145485

RESUMO

OBJECTIVE: Patient registries are considered an important foundation of chronic disease management, and diabetes patient registries are associated with better processes and outcomes of care. The purpose of this article is to describe the development and use of registries in the Alberta's Caring for Diabetes (ABCD) project to identify and reach target populations for quality-improvement interventions in the primary care setting. METHODS: We applied the reach, effectiveness, adoption, implementation and maintenance (RE-AIM) framework and expanded the definition of reach beyond the individual (i.e. patient) level to include the ability to identify target populations at an organizational level. To characterize reach and the implementation of registries, semistructured interviews were conducted with key informants, and a usual-care checklist was compiled for each participating Primary Care Network (PCN). Content analysis was used to analyze qualitative data. RESULTS: Using registries to identify and recruit participants for the ABCD interventions proved challenging. The quality of the registries depended on whether physicians granted PCN access to patient lists, the strategies used in development, the reliability of diagnostic information and the data elements collected. In addition, once a diabetes registry was developed, there was limited ability to update it. CONCLUSIONS: Proactive management of chronic diseases like diabetes requires the ability to reach targeted patients at the population level. We observed several challenges to the development and application of patient registries. Given the importance of valid registries, strong collaborations and novel strategies that involve policy-makers, PCNs and providers are needed to help find solutions to improve registry quality and resolve maintenance issues.


Assuntos
Diabetes Mellitus Tipo 2 , Atenção Primária à Saúde , Melhoria de Qualidade/organização & administração , Sistema de Registros , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Humanos , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/organização & administração
13.
Dev Neurosci ; 37(4-5): 453-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25720426

RESUMO

Exposure to adverse prenatal factors can result in abnormal brain development, contributing to the aetiology of several neurological disorders. Intrauterine insults could occur during neurogenesis and gliogenesis, disrupting these events. Here we investigate the effects of chronic placental insufficiency (CPI) on cell proliferation and the microenvironment in the subventricular zone (SVZ). At 30 days of gestation (DG; term ∼67 DG), CPI was induced in pregnant guinea pigs via unilateral uterine artery ligation to produce growth-restricted (GR) foetuses (n = 7); controls (n = 6) were from the unoperated horn. At 60 DG, foetal brains were stained immunohistochemically to identify proliferating cells (Ki67), immature neurons (polysialylated neuronal cell adhesion molecule), astrocytes (glial fibrillary acidic protein), microglia (ionised calcium-binding adaptor molecule-1, Iba-1) and the microvasculature (von Willebrand factor) in the SVZ. There was no overall difference (p > 0.05) in the total number of Ki67-immunoreactive (IR) cells, the percentage of SVZ occupied by blood vessels or the density of Iba-1-IR microglia in control versus GR foetuses. However, regression analysis across both groups revealed that both the number of Ki67-IR cells and the percentage of SVZ occupied by blood vessels in the ventral SVZ were negatively correlated (p < 0.05) with brain weight. Furthermore, in the SVZ (dorsal and ventral) the density of blood vessels positively correlated (p < 0.05) with the number of Ki67-IR cells. Double-labelling immunofluorescence suggested that the majority of proliferating cells were likely to be neural precursor cells. Thus, we have demonstrated an association between angiogenesis and neurogenesis in the foetal neurogenic niche and have identified a window of opportunity for the administration of trophic support to enhance a neuroregenerative response.


Assuntos
Proliferação de Células/fisiologia , Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/fisiopatologia , Ventrículos Laterais/crescimento & desenvolvimento , Neovascularização Fisiológica/fisiologia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Animais , Feminino , Cobaias , Insuficiência Placentária/fisiopatologia , Gravidez
14.
Diabetes Care ; 37(12): 3220-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25315205

RESUMO

OBJECTIVE: Depressive symptoms are common and, when coexisting with diabetes, worsen outcomes and increase health care costs. We evaluated a nurse case-manager-based collaborative primary care team model to improve depressive symptoms in diabetic patients. RESEARCH DESIGN AND METHODS: We conducted a controlled implementation trial in four nonmetropolitan primary care networks. Eligible patients had type 2 diabetes and screened positive for depressive symptoms, based on a Patient Health Questionnaire (PHQ) score of ≥10. Patients were allocated using an "on-off" monthly time series. Intervention consisted of case-managers working 1:1 with patients to deliver individualized care. The main outcome was improvement in PHQ scores at 12 months. A concurrent cohort of 71 comparable patients was used as nonscreened usual care control subjects. RESULTS: Of 1,924 patients screened, 476 (25%) had a PHQ score >10. Of these, 95 were allocated to intervention and 62 to active control. There were no baseline differences between groups: mean age was 57.8 years, 55% were women, and the mean PHQ score was 14.5 (SD 3.7). Intervention patients had greater 12-month improvements in PHQ (7.3 [SD 5.6]) compared with active-control subjects (5.2 [SD 5.7], P = 0.015). Recovery of depressive symptoms (i.e., PHQ reduced by 50%) was greater among intervention patients (61% vs. 44%, P = 0.03). Compared with trial patients, nonscreened control subjects had significantly less improvement at 12 months in the PHQ score (3.2 [SD 4.9]) and lower rates of recovery (24%, P < 0.05 for both). CONCLUSIONS: In patients with type 2 diabetes who screened positive for depressive symptoms, collaborative care improved depressive symptoms, but physician notification and follow-up was also a clinically effective initial strategy compared with usual care.


Assuntos
Redes Comunitárias , Comportamento Cooperativo , Depressão/complicações , Depressão/terapia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Atenção Primária à Saúde/métodos , Adulto , Idoso , Redes Comunitárias/organização & administração , Pesquisa Comparativa da Efetividade , Continuidade da Assistência ao Paciente/organização & administração , Depressão/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Medicina de Precisão/métodos , Atenção Primária à Saúde/organização & administração
15.
Pediatr Res ; 76(1): 54-63, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24739937

RESUMO

BACKGROUND: Caffeine is widely used to treat apnea of prematurity, but the standard dosing regimen is not always sufficient to prevent apnea. Before higher doses of caffeine can be used, their effects on the immature brain need to be carefully evaluated. Our aim was to determine the impact of daily high-dose caffeine administration on the developing white matter of the immature ovine brain. METHODS: High-dose caffeine (25 mg/kg caffeine base loading dose; 20 mg/kg daily maintenance dose; n = 9) or saline (n = 8) were administered to pregnant sheep from 0.7 to 0.8 of term, equivalent to approximately 27-34 wk in humans. At 0.8 of term, the white and gray matter were assessed histologically and immunohistochemically. RESULTS: Daily caffeine administration led to peak caffeine concentration of 32 mg/l in fetal plasma at 1 h, followed by a gradual decline, with no effects on mean arterial pressure and heart rate. Initial caffeine exposure led to transient, mild alkalosis in the fetus but did not alter oxygenation. At necropsy, there was no effect of daily high-dose caffeine on brain weight, oligodendrocyte density, myelination, axonal integrity, microgliosis, astrogliosis, apoptosis, or neuronal density. CONCLUSION: Daily high-dose caffeine administration does not appear to adversely affect the developing white matter at the microstructural level.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Cafeína/efeitos adversos , Exposição Materna/efeitos adversos , Animais , Apoptose , Axônios/metabolismo , Cafeína/sangue , Feminino , Gliose/patologia , Proteína Básica da Mielina/metabolismo , Bainha de Mielina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Oligodendroglia/citologia , Gravidez , Prenhez , Ovinos , Fatores de Tempo
16.
Pediatr Res ; 76(1): 64-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24713816

RESUMO

BACKGROUND: The effects of levosimendan (Levo) on injury patterns in the immature brain following cardiopulmonary bypass (CPB) are unknown. METHODS: Eighteen 3- to 4-wk-old anesthetized lambs, instrumented with vascular catheters and aortic and right carotid artery flow probes, were allocated to non-CPB, CPB, or CPB+Levo groups (each n = 6). After 120 min CPB with 90 min aortic cross-clamp, CPB animals received dopamine, and CPB+Levo animals both dopamine and Levo, for 4 h. All lambs then underwent brain magnetic resonance imaging, followed by postmortem brain perfusion fixation for immunohistochemical studies. RESULTS: In CPB lambs, aortic (P < 0.05) and carotid artery (P < 0.01) blood flows fell by 29 and 30%, respectively, between 2 and 4 h after cross-clamp removal but were unchanged in the CPB+Levo group. No brain injury was detectable with magnetic resonance imaging in either CPB or CPB+Levo lambs. However, on immunohistochemical analysis, white matter astrocyte density of both groups was higher than in non-CPB lambs (P < 0.05), while white matter microglial density was higher (P < 0.05), but markers of cortical oxidative stress were less prevalent in CPB+Levo than CPB lambs. CONCLUSION: While Levo prevented early postoperative falls in cardiac output and carotid artery blood flow in a lamb model of infant CPB, this was associated with heterogeneous neuroglial activation and manifestation of markers of oxidative stress.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Ponte Cardiopulmonar/efeitos adversos , Hidrazonas/uso terapêutico , Piridazinas/uso terapêutico , Animais , Antiarrítmicos/uso terapêutico , Gasometria , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Débito Cardíaco/efeitos dos fármacos , Ponte Cardiopulmonar/métodos , Artérias Carótidas/efeitos dos fármacos , Modelos Animais de Doenças , Dopamina/química , Hemodinâmica/efeitos dos fármacos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Neuroglia/efeitos dos fármacos , Estresse Oxidativo , Ovinos , Simendana
17.
Reprod Sci ; 21(5): 658-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-21421894

RESUMO

OBJECTIVE: To determine the effect of intrauterine inflammation on fetal responses to umbilical cord occlusion (UCO). STUDY DESIGN: In pregnant sheep, lipopolysaccharide (LPS) or saline (SAL) was infused intra-amniotically for 4 weeks from 80 days of gestation (d). At 110 d, fetuses were instrumented for UCOs (5 × 2-minutes, 30-minute intervals: LPS + UCO, n = 6; SAL + UCO, n = 8) or no UCO (sham, n = 6) on 117 and 118 d. Tissues were collected at 126 d. RESULTS: Fetal physiological responses to UCO were similar between LPS + UCO and SAL + UCO. Histologic chorioamnionitis and increased amniotic fluid interleukin 8 (IL-8) were observed in LPS + UCO pregnancies (versus SAL + UCO, P < .05). CNPase-positive oligodendrocyte number in the cerebral white matter was lower in LPS + UCO and SAL + UCO than sham (P < .05); there was no effect on astrocytes or activated microglia/macrophages. Two of the SAL + UCO fetuses had white matter lesions; none were observed in LPS + UCO or sham. CONCLUSION: Chronic pre-existing intrauterine inflammation did not exacerbate fetal brain injury induced by intermittent UCO.


Assuntos
Encéfalo/embriologia , Encéfalo/patologia , Desenvolvimento Fetal/fisiologia , Hipóxia Fetal/patologia , Cordão Umbilical/patologia , Animais , Encéfalo/metabolismo , Doença Crônica , Feminino , Hipóxia Fetal/sangue , Feto , Inflamação/sangue , Inflamação/patologia , Gravidez , Ovinos
18.
Psychoneuroendocrinology ; 38(2): 263-70, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22749310

RESUMO

Psychiatric disorders associated with elevated stress levels, such as depression, are present in many epilepsy patients, including those with mesial Temporal Lobe Epilepsy (mTLE). Evidence suggests that these psychiatric disorders can predate the onset of epilepsy, suggesting a causal/contributory role. Prolonged exposure to elevated corticosterone, used as a model of chronic stress/depression, accelerates limbic epileptogenesis in the amygdala kindling model. The current study examined whether exposure to repeated stress could similarly accelerate experimental epileptogenesis. Female adult non-epileptic Wistar rats were implanted with a bipolar electrode into the left amygdala, and were randomly assigned into stressed (n=18) or non-stressed (n=19) groups. Rats underwent conventional amygdala kindling (two electrical stimulations per day) until 5 Class V seizures had been experienced ('the fully kindled state'). Stressed rats were exposed to 30min restraint immediately prior to each kindling stimulation, whereas non-stressed rats received control handling. Restraint stress increased circulating corticosterone levels (pre-stress: 122±17ng/ml; post-stress: 632±33ng/ml), with no habituation observed over the experiment. Stressed rats reached the 'fully kindled state' in significantly fewer stimulations than non-stressed rats (21±1 vs 33±3 stimulations; p=0.022; ANOVA), indicative of a vulnerability to epileptogenesis. Further, seizure durations were significantly longer in stressed rats (p<0.001; ANOVA). These data demonstrate that exposure to repeated experimental stress accelerates the development of limbic epileptogenesis, an effect which may be related to elevated corticosterone levels. This may have implications for understanding the effects of chronic stress and depression in disease onset and progression of mTLE in humans.


Assuntos
Tonsila do Cerebelo/fisiologia , Epilepsia/fisiopatologia , Excitação Neurológica/fisiologia , Estresse Psicológico/fisiopatologia , Animais , Corticosterona/metabolismo , Modelos Animais de Doenças , Estimulação Elétrica/métodos , Epilepsia/sangue , Epilepsia/complicações , Feminino , Habituação Psicofisiológica/fisiologia , Ratos , Ratos Wistar , Restrição Física/métodos , Restrição Física/fisiologia , Estresse Psicológico/sangue , Estresse Psicológico/complicações
19.
Ann Fam Med ; 10(6): 538-46, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23149531

RESUMO

PURPOSE: Influenza and pneumococcal vaccination rates remain below national targets. We systematically reviewed the effectiveness of quality improvement interventions for increasing the rates of influenza and pneumococcal vaccinations among community-dwelling adults. METHODS: We included randomized and nonrandomized studies with a concurrent control group. We estimated pooled odds ratios using random effects models, and used the Downs and Black tool to assess the quality of included studies. RESULTS: Most studies involved elderly primary care patients. Interventions were associated with improvements in the rates of any vaccination (111 comparisons in 77 studies, pooled odds ratio [OR] = 1.61, 95% CI, 1.49-1.75), and influenza (93 comparisons, 65 studies, OR = 1.46, 95% CI, 1.35-1.57) and pneumococcal (58 comparisons, 35 studies, OR = 2.01, 95% CI, 1.72-2.3) vaccinations. Interventions that appeared effective were patient financial incentives (influenza only), audit and feedback (influenza only), clinician reminders, clinician financial incentives (influenza only), team change, patient outreach, delivery site changes (influenza only), clinician education (pneumococcus only), and case management (pneumococcus only). Patient outreach was more effective if personal contact was involved. Team changes were more effective where nurses administered influenza vaccinations independently. Heterogeneity in some pooled odds ratios was high, however, and funnel plots showed signs of potential publication bias. Study quality varied but was not associated with outcomes. CONCLUSIONS: Quality improvement interventions, especially those that assign vaccination responsibilities to nonphysician personnel or that activate patients through personal contact, can modestly improve vaccination rates in community-dwelling adults. To meet national policy targets, more-potent interventions should be developed and evaluated.


Assuntos
Programas de Imunização , Vacinas contra Influenza/administração & dosagem , Vacinas Pneumocócicas/administração & dosagem , Melhoria de Qualidade/estatística & dados numéricos , Qualidade da Assistência à Saúde/estatística & dados numéricos , Adulto , Humanos , Atenção Primária à Saúde
20.
BMJ Open ; 2(5)2012.
Artigo em Inglês | MEDLINE | ID: mdl-23103609

RESUMO

INTRODUCTION: Diabetes represents a major public health and health system burden. As part of the Alberta's Caring for Diabetes (ABCD) Project, two quality-improvement interventions are being piloted in four Primary Care Networks in Alberta. Gaps between health research, policy and practice have been documented and the need to evaluate the impact of public health interventions in real-world settings to inform decision-making and clinical practice is paramount. In this article, we describe the application of the RE-AIM framework to evaluate the interventions beyond effectiveness. METHODS AND ANALYSIS: Two quality-improvement interventions were implemented, based on previously proven effective models of care and are directed at improving the physical and mental health of patients with type-2 diabetes. Our goal is to adapt and apply the RE-AIM framework, using a mixed-methods approach, to understand the impact of the interventions to inform policy and clinical decision-making. We present the proposed measures, data sources and data management and analysis strategies used to evaluate the interventions by RE-AIM dimension. ETHICS AND DISSEMINATION: Ethics approval for the ABCD Project has been granted from the Health Research Ethics Board (HREB #PRO00012663) at the University of Alberta. The RE-AIM framework will be used to structure our dissemination activities by dimension. RESULTS: It will be presented at relevant conferences and prepared for publication in peer-reviewed journals. Various products, such as presentations, briefing reports and webinars, will be developed to inform key stakeholders of the findings. Presentation of findings by RE-AIM dimension will facilitate discussion regarding the public health impact of the two interventions within the primary care context of Alberta and lessons learned to be used in programme planning and care delivery for patients with type-2 diabetes. It will also promote the application of evaluation models to better assess the impact of community-based primary healthcare interventions through our dissemination activities.

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