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1.
Phys Rev Lett ; 128(23): 232501, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35749172

RESUMO

The Baksan Experiment on Sterile Transitions (BEST) was designed to investigate the deficit of electron neutrinos ν_{e} observed in previous gallium-based radiochemical measurements with high-intensity neutrino sources, commonly referred to as the "gallium anomaly," which could be interpreted as evidence for oscillations between ν_{e} and sterile neutrino (ν_{s}) states. A 3.414-MCi ^{51}Cr ν_{e} source was placed at the center of two nested Ga volumes and measurements were made of the production of ^{71}Ge through the charged current reaction, ^{71}Ga(ν_{e},e^{-})^{71}Ge, at two average distances. The measured production rates for the inner and the outer targets, respectively, are [54.9_{-2.4}^{+2.5}(stat)±1.4(syst)] and [55.6_{-2.6}^{+2.7}(stat)±1.4(syst)] atoms of ^{71}Ge/d. The ratio (R) of the measured rate of ^{71}Ge production at each distance to the expected rate from the known cross section and experimental efficiencies are R_{in}=0.79±0.05 and R_{out}=0.77±0.05. The ratio of the outer to the inner result is 0.97±0.07, which is consistent with unity within uncertainty. The rates at each distance were found to be similar, but 20%-24% lower than expected, thus reaffirming the anomaly. These results are consistent with ν_{e}→ν_{s} oscillations with a relatively large Δm^{2} (>0.5 eV^{2}) and mixing sin^{2}2θ (≈0.4).

2.
J Frailty Aging ; 11(2): 163-168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35441193

RESUMO

BACKGROUND: Information on the spatial distribution of the frail population is crucial to inform service planning in health and social care. OBJECTIVES: To estimate small-area frailty prevalence among older adults using survey data. To assess whether prevalence differs between urban, rural, coastal and inland areas of England. DESIGN: Using data from the English Longitudinal Study of Ageing (ELSA), ordinal logistic regression was used to predict the probability of frailty, according to age, sex and area deprivation. Probabilities were applied to demographic and economic information in 2020 population projections to estimate the district-level prevalence of frailty. RESULTS: The prevalence of frailty in adults aged 50+ (2020) in England was estimated to be 8.1 [95% CI 7.3-8.8]%. We found substantial geographic variation, with the prevalence of frailty varying by a factor of 4.0 [3.5-4.4] between the most and least frail areas. A higher prevalence of frailty was found for urban than rural areas, and coastal than inland areas. There are widespread geographic inequalities in healthy ageing in England, with older people in urban and coastal areas disproportionately frail relative to those in rural and inland areas. CONCLUSIONS: Interventions aimed at reducing inequalities in healthy ageing should be targeted at urban and coastal areas, where the greatest benefit may be achieved.


Assuntos
Fragilidade , Idoso , Envelhecimento , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Humanos , Estudos Longitudinais , Prevalência
3.
Resusc Plus ; 7: 100148, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34286310

RESUMO

BACKGROUND: Research priority setting in health care has historically been done by expert health care providers and researchers and has not involved patients, family or the public. Survivors & family members have been particularly absent from this process in the field of resuscitation research and specifically adult out of hospital cardiac arrest (OHCA). As such, we sought to conduct a priority setting exercise in partnership with survivors, lay responders and their families in order to ensure that their priorities were visible. We partnered with the James Lind Alliance (UK) and used their commonly used consensus methodology for Public Priority Setting Partnerships (PSPs) to identify research priorities that reflected the perspectives of all stakeholders. METHODS: We used two rounds of public and health care professional surveys to create the initial priority lists. The initial survey collected open-ended questions while the second round consolidated the list of initial questions into a refined list for prioritization. This was done by reviewing existing evidence and thematic categorization by the multi-disciplinary steering committee. An in-person consensus workshop was conducted to come to consensus on the top ten priorities from all perspectives. The McMaster PPEET tool was used to measure engagement. RESULTS: The initial survey yielded more than 425 responses and 1450 "questions" from survivors and family members (18%), lay responders, health care providers and others. The second survey asked participants to rank a short list of 125 questions. The final top 25 questions were brought to the in-person meeting, and a top ten were selected through the JLA consensus process. The final list of top ten questions included how to improve the rate of lay responder CPR, what interventions used at the scene of an arrest can improve resuscitation and survival, how survival can be improved in rural areas of Canada, what resuscitation medications are most effective, what care patient's family members need, what post-discharge support is needed for survivors, how communication should work for everyone involved with a cardiac arrest, what factors best predict neurologically intact survival, whether biomarkers/genetic tests are effective in predicting OHCA and more research on the short and long-term psycho-social impacts of OHCA on survivors. The PPEET showed overwhelmingly positive results for the patient and family engagement experience during the final workshop. CONCLUSIONS: This inclusive research priority setting provides essential information for those doing resuscitation research internationally. The results provide a guide for priority areas of research and should drive our community to focus on questions that matter to survivors and their families in our work. In particular the Canadian Resuscitation Outcomes Consortium will be incorporating the top ten list into its strategic plan for the future.

4.
Epilepsy Res ; 175: 106680, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34102391

RESUMO

Temporal lobe epilepsy (TLE) in children is considered different from that in adults. As such, characterizing the structural lesions present in pediatric patients with TLE and their association with long-term seizure control is important. Here, we aimed to assess the concordance between preoperative imaging and postoperative histopathological diagnoses and their associations with seizure outcomes in pediatric patients with TLE undergoing temporal lobe surgery. We retrospectively reviewed the charts of pediatric patients with TLE who underwent surgical treatment between 1988 and 2020 as a part of the Comprehensive Epilepsy Program at the University of Alberta. Demographic, age at seizure onset, age at surgery, preoperative electroencephalography (EEG), long-term video EEG, imaging (magnetic resonance imaging [MRI] and computed tomography), neuropathology, and long-term seizure outcome data were acquired and analyzed. One hundred and seventeen patients underwent surgery for refractory TLE; the preoperative MRI diagnosis was concordant with the histopathological diagnosis in 76 % of cases. Tumors were identified with high accuracy (91 %). Mesial temporal sclerosis (MTS) was strongly associated with an excellent outcome after surgery (94 %). Patients with normal imaging results or non-specific pathologies were more likely to experience poor seizure outcomes after surgery (50 %). The radiological identification of lesions was associated with good long-term seizure outcomes, whereas normal MRI results were associated with significantly poorer long-term seizure outcomes. An accurate preoperative MRI is essential to epilepsy surgery since it impacts all stages of management; these results will thereafter help inform practitioners' efforts to predict seizure outcome.


Assuntos
Epilepsia do Lobo Temporal , Adulto , Criança , Eletroencefalografia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Estudos Retrospectivos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Lobo Temporal/cirurgia , Resultado do Tratamento
5.
Phys Chem Chem Phys ; 22(36): 20941-20950, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32926031

RESUMO

A nominal Bi-excess starting composition of sodium bismuth titanate, Na0.5Bi0.51TiO3.015 (NB0.51T) produces dielectric ceramics that exhibit mixed n-type and oxide-ion conductivity with an ionic transport number of ∼0.1 at ≥600 °C. The bulk electrical conductivity, σb, of NB0.51T ceramics under a dc bias field of ≤100 V cm-1 has been investigated by impedance spectroscopy. Over the temperature range ∼550 to 750 °C, σb increases by up to one order of magnitude under the dc bias and returns to its initial value on removal of the bias. The enhancement of conductivity is dependent on temperature, atmosphere, dc bias field and the electrode materials. A maximum conductivity enhancement of >2000% is achieved at 600 °C in nitrogen using Pt electrodes. This is in contrast to that observed for other n-type perovskite titanates and oxygen-deficient rutile where σb is suppressed under a dc bias. This 'unusual' non-ohmic behaviour is attributed mainly to the influence of highly mobile oxygen vacancies in NB0.51T. The field-enhanced σb is best described to be a consequence of increased pumping of oxygen from the cathode to the anode, in which the electrode reactions play an important role. In addition, dissociation of defect clusters may also contribute to the enhanced σb under a dc bias. The high, fast and reversible response to the dc bias voltage may expand the potential application of NBT-based materials to memory devices.

6.
J Child Neurol ; 34(10): 549-555, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31066328

RESUMO

INTRODUCTION: Neurovascular lesions are rare and understudied in the pediatric population. Their initial presentation can range from seizures to focal neurologic deficits, as well as headaches. The goal of this study was to examine the clinical presentation and natural history of neurovascular lesions in children with epilepsy. METHODS: We reviewed all pediatric epilepsy patients with neurovascular lesions diagnosed between 2006 and 2018 at the University of Alberta and the Stollery Children's Hospital, Edmonton, Canada. Initial clinical presentation and brain imaging, as well as long-term epilepsy and postsurgical outcome, were assessed. RESULTS: Of the 14 patients, 10 patients had an initial presentation of focal seizures with impaired awareness, whereas 2 patients presented with headache, 1 presented with visual field defects as well as chronic headaches, and 1 with decreased level of consciousness. Seven patients had cavernous angiomas, 6 had arteriovenous malformation, and 1 patient had an arteriovenous fistula. Notably, all patients with cavernous angiomas and 4 of 6 patients with arteriovenous malformations presented with seizures. Among 9 of the 14 who underwent neurovascular corrective surgery, all 9 patients required long-term antiepileptic treatment of at least 1 antiepileptic drug for seizure control after the operation. CONCLUSION: In this novel case series, we describe focal seizures as the initial presentation of pediatric neurovascular lesions. This clinical presentation appears to be independent of the type of neurovascular lesion. Furthermore, unlike our pediatric surgical patients with epilepsy due to other causes, seizure freedom following neurovascular surgery is limited, and patients require long-term antiepileptic treatment.


Assuntos
Epilepsia/complicações , Doenças Vasculares/complicações , Adolescente , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Criança , Pré-Escolar , Epilepsia/diagnóstico , Epilepsia/terapia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Convulsões/complicações , Convulsões/diagnóstico , Convulsões/terapia , Doenças Vasculares/diagnóstico , Doenças Vasculares/terapia
7.
J Neurosurg Pediatr ; 22(3): 276-282, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29932370

RESUMO

OBJECTIVE The aim of this study was to investigate long-term seizure outcome, rate of reoperation, and postoperative neuropsychological performance following selective amygdalohippocampectomy (SelAH) or anterior temporal lobectomy (ATL) in pediatric patients with medically refractory temporal lobe epilepsy (TLE). METHODS The authors performed a retrospective review of cases of medically refractory pediatric TLE treated initially with either SelAH or ATL. Standardized pre- and postoperative evaluation included seizure charting, surface and long-term video-electroencephalography, 1.5-T MRI, and neuropsychological testing. RESULTS A total of 79 patients treated initially with SelAH (n = 18) or ATL (n = 61) were included in this study, with a mean follow-up of 5.3 ± 4 years (range 1-16 years). The patients' average age at initial surgery was 10.6 ± 5 years, with an average surgical delay of 5.7 ± 4 years between seizure onset and surgery. Seizure freedom (Engel I) following the initial operation was significantly more likely following ATL (47/61, 77%) than SelAH (8/18, 44%; p = 0.017, Fisher's exact test). There was no statistically significant difference in the proportion of patients with postoperative neuropsychological deficits following SelAH (8/18, 44%) or ATL (21/61, 34%). However, reoperation was significantly more likely following SelAH (8/18, 44%) than after ATL (7/61, 11%; p = 0.004) and was more likely to result in Engel I outcome for ATL after failed SelAH (7/8, 88%) than for posterior extension after failed ATL (1/7, 14%; p = 0.01). Reoperation was well tolerated without significant neuropsychological deterioration. Ultimately, including 15 reoperations, 58 of 79 (73%) patients were free from disabling seizures at the most recent follow-up. CONCLUSIONS SelAH among pediatric patients with medically refractory unilateral TLE yields significantly worse rates of seizure control compared with ATL. Reoperation is significantly more likely following SelAH, is not associated with incremental neuropsychological deterioration, and frequently results in freedom from disabling seizures. These results are significant in that they argue against using SelAH for pediatric TLE surgery.


Assuntos
Tonsila do Cerebelo/cirurgia , Lobectomia Temporal Anterior/métodos , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/cirurgia , Psicocirurgia/métodos , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Masculino , Neuroimagem , Testes Neuropsicológicos , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
8.
Hum Reprod Open ; 2018(3): hoy010, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30895251

RESUMO

STUDY QUESTION: Can maternal and offspring high-fat diet (HFD)-induced changes in mRNA expression levels in mice be ameliorated by interventions in female offspring? SUMMARY ANSWER: Our results indicate that exercise and nicotinamide mononucleotide (NMN) can ameliorate the negative effects of maternal and post-weaning HFD in female offspring. WHAT IS KNOWN ALREADY: Maternal and post-weaning HFD can perturb offspring developmental trajectories. As rates of maternal obesity are rising globally, there is a need for effective treatments in offspring to ameliorate the negative effects from a maternal obesogenic environment. Modulation of the nicotinamide adenine dinucleotide (NAD+) pathway by exercise and the NAD+ precursor NMN has previously been shown to reduce the effects of obesity. STUDY DESIGN SIZE DURATION: This study consisted of a multigenerational study using C57Bl6 mice. Mice were fed a control (chow) or HFD ad libitum throughout mating, pregnancy and lactation (n = 13-25). Female offspring (n = 72) were then also supplied either a chow or HFD post-weaning. At 9 weeks of age offspring from HFD dams were subjected to exercise on a treadmill for 9 weeks or at 16 weeks of age administered NMN (i.p.) for 2.5 weeks. At 18.5 weeks mice were euthanized and ovaries and cumulus-oocyte complexes (COC) were collected to examine the possibility of ameliorating the negative effects of maternal and post-weaning HFD. PARTICIPANTS/MATERIALS SETTING METHODS: Ovary and COC mRNA expression was analysed using RT-qPCR. An initial screen of candidate genes was developed to test which molecular pathways may be involved in generating adverse reproductive system effects. For histological analysis, ovarian tissue was fixed in paraformaldehyde and embedded in paraffin and stained with haematoxylin and eosin. The numbers of primordial, primary, secondary and antral follicles were counted. MAIN RESULTS AND THE ROLE OF CHANCE: In the offspring's COC, maternal obesity increased both growth differentiation factor 9 (Gdf9: 2-fold; P < 0.05, HFD versus chow) and bone morphogenetic protein 15 (Bmp15: 4-fold; P < 0.05, HFD versus chow) mRNA expression levels while exercise and NMN interventions did not regulate Gdf9 and Bmp15 in the same manner. In whole ovary, maternal diet programmed a 25-50% reduction in FSH receptor and sirtuin-3 mRNA expression levels in daughter ovaries (P < 0.05, HFD versus chow). There was a significant interaction between HFD and intervention on the proportion of large preantral and preovulatory follicles (P < 0.05). However, the increase in preovulatory follicles did not translate to increased oocyte yield. NMN administration resulted in reduced body weight in HFD-fed individuals. LIMITATIONS REASONS FOR CAUTION: It is unclear if the changes in oocyte mRNA expression levels reported here will impact oocyte quality and fertility in offspring. Offspring ovulation rate or fecundity could not be studied here and fertility trials are required to determine if the changes in gene expression do reduce fertility. WIDER IMPLICATIONS OF THE FINDINGS: Our results demonstrate that maternal and offspring HFD perturbs key signalling pathways that are known to regulate fertility in mice, highlighting the importance of interventions in helping to prevent the declining rates of fertility in the context of the current obesity epidemic. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants and fellowships from the National Health and Medical Research Council to R.B.G. (APP1023210, APP1062762, APP1117538) and to M.J.M. and D.A.S. (APP1044295). DAS is a consultant to and inventor on patents licenced to Ovascience, Metrobiotech and GlaxoSmithKline. The other authors declare that there is no conflict of interest.

9.
Transl Psychiatry ; 7(8): e1192, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28786974

RESUMO

The immune system is implicated in the pathogenesis of schizophrenia, with elevated proinflammatory cytokine mRNAs found in the brains of ~40% of individuals with the disorder. However, it is not clear if antibodies (specifically immunoglobulin-γ (IgG)) can be found in the brain of people with schizophrenia and if their abundance relates to brain inflammatory cytokine mRNA levels. Therefore, we investigated the localization and abundance of IgG in the frontal cortex of people with schizophrenia and controls, and the impact of proinflammatory cytokine status on IgG abundance in these groups. Brain IgGs were detected surrounding blood vessels in the human and non-human primate frontal cortex by immunohistochemistry. IgG levels did not differ significantly between schizophrenia cases and controls, or between schizophrenia cases in 'high' and 'low' proinflammatory cytokine subgroups. Consistent with the existence of IgG in the parenchyma of human brain, mRNA and protein of the IgG transporter (FcGRT) were present in the brain, and did not differ according to diagnosis or inflammatory status. Finally, brain-reactive antibody presence and abundance was investigated in the blood of living people. The plasma of living schizophrenia patients and healthy controls contained antibodies that displayed positive binding to Rhesus macaque cerebellar tissue, and the abundance of these antibodies was significantly lower in patients than controls. These findings suggest that antibodies in the brain and brain-reactive antibodies in the blood are present under normal circumstances.


Assuntos
Córtex Cerebral/imunologia , Imunoglobulina G/metabolismo , Esquizofrenia/imunologia , Adulto , Animais , Córtex Cerebral/metabolismo , Feminino , Humanos , Imunoglobulina G/sangue , Macaca mulatta , Masculino , Esquizofrenia/metabolismo
10.
eNeuro ; 4(1)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28451631

RESUMO

Fragile X syndrome is a genetic condition resulting from FMR1 gene mutation that leads to intellectual disability, autism-like symptoms, and sensory hypersensitivity. Arbaclofen, a GABA-B agonist, has shown efficacy in some individuals with FXS but has become unavailable after unsuccessful clinical trials, prompting interest in publicly available, racemic baclofen. The present study investigated whether racemic baclofen can remediate abnormalities of neural circuit function, sensory processing, and behavior in Fmr1 knockout mice, a rodent model of fragile X syndrome. Fmr1 knockout mice showed increased baseline and auditory-evoked high-frequency gamma (30-80 Hz) power relative to C57BL/6 controls, as measured by electroencephalography. These deficits were accompanied by decreased T maze spontaneous alternation, decreased social interactions, and increased open field center time, suggestive of diminished working memory, sociability, and anxiety-like behavior, respectively. Abnormal auditory-evoked gamma oscillations, working memory, and anxiety-related behavior were normalized by treatment with baclofen, but impaired sociability was not. Improvements in working memory were evident predominantly in mice whose auditory-evoked gamma oscillations were dampened by baclofen. These findings suggest that racemic baclofen may be useful for targeting sensory and cognitive disturbances in fragile X syndrome.


Assuntos
Baclofeno/farmacologia , Potenciais Evocados Auditivos/efeitos dos fármacos , Síndrome do Cromossomo X Frágil/complicações , Agonistas dos Receptores de GABA-B/farmacologia , Transtornos Mentais/etiologia , Transtornos Mentais/patologia , Estimulação Acústica , Animais , Modelos Animais de Doenças , Eletroencefalografia , Potenciais Evocados Auditivos/genética , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/genética , Relações Interpessoais , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise Espectral
11.
Oncogene ; 36(4): 559-569, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-27345396

RESUMO

Tumors utilize aerobic glycolysis to support growth and invasion. However, the molecular mechanisms that link metabolism with invasion are not well understood. The nutrient sensor O-linked-ß-N-acetylglucosamine (O-GlcNAc) transferase (OGT) modifies intracellular proteins with N-acetylglucosamine. Cancers display elevated O-GlcNAcylation and suppression of O-GlcNAcylation inhibits cancer invasion and metastasis. Here, we show that the regulation of cancer invasion by OGT is dependent on the NAD+-dependent deacetylase SIRT1. Reducing O-GlcNAcylation elevates SIRT1 levels and activity in an AMPK (AMP-activated protein kinase α)-dependent manner. Reduced O-GlcNAcylation in cancer cells leads to SIRT1-mediated proteasomal degradation of oncogenic transcription factor FOXM1 in an MEK/ERK-dependent manner. SIRT1 is critical for OGT-mediated regulation of FOXM1 ubiquitination and reducing SIRT1 activity reverses OGT-mediated regulation of FOXM1. Moreover, we show that SIRT1 levels are required for OGT-mediated regulation of invasion and metastasis in breast cancer cells. Thus, O-GlcNAcylation is a central component linking metabolism to invasion and metastasis via an SIRT1/ERK/FOXM1 axis.


Assuntos
Neoplasias da Mama/metabolismo , Proteína Forkhead Box M1/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Sirtuína 1/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Proteína Forkhead Box M1/genética , Glicosilação , Xenoenxertos , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Metástase Neoplásica , Sirtuína 1/genética
12.
Neurosci Biobehav Rev ; 76(Pt B): 235-253, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27235081

RESUMO

Brains are constantly flooded with sensory information that needs to be filtered at the pre-attentional level and integrated into endogenous activity in order to allow for detection of salient information and an appropriate behavioral response. People with Autism Spectrum Disorder (ASD) or Fragile X Syndrome (FXS) are often over- or under-reactive to stimulation, leading to a wide range of behavioral symptoms. This altered sensitivity may be caused by disrupted sensory processing, signal integration and/or gating, and is often being neglected. Here, we review translational experimental approaches that are used to investigate sensory processing in humans with ASD and FXS, and in relevant rodent models. This includes electroencephalographic measurement of event related potentials, neural oscillations and mismatch negativity, as well as habituation and pre-pulse inhibition of startle. We outline robust evidence of disrupted sensory processing in individuals with ASD and FXS, and in respective animal models, focusing on the auditory sensory domain. Animal models provide an excellent opportunity to examine common mechanisms of sensory pathophysiology in order to develop therapeutics.


Assuntos
Transtorno do Espectro Autista , Síndrome do Cromossomo X Frágil , Animais , Encéfalo , Eletroencefalografia , Humanos , Modelos Animais
13.
BMJ Open Respir Res ; 3(1): e000156, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27843550

RESUMO

INTRODUCTION: Solitary pulmonary nodules (SPNs) are common on CT. The most cost-effective investigation algorithm is still to be determined. Dynamic contrast-enhanced CT (DCE-CT) is an established diagnostic test not widely available in the UK currently. METHODS AND ANALYSIS: The SPUtNIk study will assess the diagnostic accuracy, clinical utility and cost-effectiveness of DCE-CT, alongside the current CT and 18-flurodeoxyglucose-positron emission tomography) (18FDG-PET)-CT nodule characterisation strategies in the National Health Service (NHS). Image acquisition and data analysis for 18FDG-PET-CT and DCE-CT will follow a standardised protocol with central review of 10% to ensure quality assurance. Decision analytic modelling will assess the likely costs and health outcomes resulting from incorporation of DCE-CT into management strategies for patients with SPNs. ETHICS AND DISSEMINATION: Approval has been granted by the South West Research Ethics Committee. Ethics reference number 12/SW/0206. The results of the trial will be presented at national and international meetings and published in an Health Technology Assessment (HTA) Monograph and in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN30784948; Pre-results.

14.
Methods Enzymol ; 574: 213-244, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27423864

RESUMO

The NAD(+)-dependent deacetylase SIRT1 plays key roles in numerous cellular processes including DNA repair, gene transcription, cell differentiation, and metabolism. Overexpression of SIRT1 protects against a number of age-related diseases including diabetes, cancer, and Alzheimer's disease. Moreover, overexpression of SIRT1 in the murine brain extends lifespan. A number of small-molecule sirtuin-activating compounds (STACs) that increase SIRT1 activity in vitro and in cells have been developed. While the mechanism for how these compounds act on SIRT1 was once controversial, it is becoming increasingly clear that they directly interact with SIRT1 and enhance its activity through an allosteric mechanism. Here, we present detailed chemical syntheses for four STACs, each from a distinct structural class. Also, we provide a general protocol for purifying active SIRT1 enzyme and outline two complementary enzymatic assays for characterizing the effects of STACs and similar compounds on SIRT1 activity.


Assuntos
Ativadores de Enzimas/química , Ativadores de Enzimas/farmacologia , Ensaios Enzimáticos/métodos , Sirtuína 1/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Regulação Alostérica/efeitos dos fármacos , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/síntese química , Humanos , Bibliotecas de Moléculas Pequenas/síntese química
16.
Transl Psychiatry ; 5: e527, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25781226

RESUMO

The olfactory mucosa (OM) is a unique source of regenerative neural tissue that is readily obtainable from living human subjects and thus affords opportunities for the study of psychiatric illnesses. OM tissues can be used, either as ex vivo OM tissue or in vitro OM-derived neural cells, to explore parameters that have been difficult to assess in the brain of living individuals with psychiatric illness. As OM tissues are distinct from brain tissues, an understanding of the neurobiology of the OM is needed to relate findings in these tissues to those of the brain as well as to design and interpret ex vivo or in vitro OM studies. To that end, we discuss the molecular, cellular and functional characteristics of cell types within the olfactory mucosa, describe the organization of the OM and highlight its role in the olfactory neurocircuitry. In addition, we discuss various approaches to in vitro culture of OM-derived cells and their characterization, focusing on the extent to which they reflect the in vivo neurobiology of the OM. Finally, we review studies of ex vivo OM tissues and in vitro OM-derived cells from individuals with psychiatric, neurodegenerative and neurodevelopmental disorders. In particular, we discuss the concordance of this work with postmortem brain studies and highlight possible future approaches, which may offer distinct strengths in comparison to in vitro paradigms based on genomic reprogramming.


Assuntos
Transtornos Mentais/patologia , Pesquisa Translacional Biomédica/métodos , Animais , Células Cultivadas , Feminino , Humanos , Técnicas In Vitro/métodos , Neurônios/patologia , Mucosa Olfatória , Gravidez , Ratos
17.
Br J Surg ; 102(1): 37-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25332065

RESUMO

BACKGROUND: Mental practice, the cognitive rehearsal of a task without physical movement, is known to enhance performance in sports and music. Investigation of this technique in surgery has been limited to basic operations. The purpose of this study was to develop mental practice scripts, and to assess their effect on advanced laparoscopic skills and surgeon stress levels in a crisis scenario. METHODS: Twenty senior surgical trainees were randomized to either conventional training or mental practice groups, the latter being trained by an expert performance psychologist. Participants' skills were assessed while performing a porcine laparoscopic jejunojejunostomy as part of a crisis scenario in a simulated operating room, using the Objective Structured Assessment of Technical Skill (OSATS) and bariatric OSATS (BOSATS) instruments. Objective and subjective stress parameters were measured, as well as non-technical skills using the Non-Technical Skills for Surgeons rating tool. RESULTS: An improvement in OSATS (P = 0.003) and BOSATS (P = 0.003) scores was seen in the mental practice group compared with the conventional training group. Seven of ten trainees improved their technical performance during the crisis scenario, whereas four of the ten conventionally trained participants deteriorated. Mental imagery ability improved significantly following mental practice training (P = 0.011), but not in the conventional group (P = 0.083). No differences in objective or subjective stress levels or non-technical skills were evident. CONCLUSION: Mental practice improves technical performance for advanced laparoscopic tasks in the simulated operating room, and allows trainees to maintain or improve their performance despite added stress.


Assuntos
Competência Clínica/normas , Educação de Pós-Graduação em Medicina/métodos , Laparoscopia/normas , Prática Psicológica , Especialidades Cirúrgicas/educação , Anastomose em-Y de Roux/educação , Feminino , Lateralidade Funcional , Humanos , Jejunostomia/educação , Laparoscopia/educação , Masculino
18.
Transl Psychiatry ; 4: e365, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24569695

RESUMO

Schizophrenia and bipolar disorder share a number of common features, both symptomatically and biologically. Abnormalities in the neuroimmune and the stress-signaling pathways have been previously identified in brains of individuals with both diseases. However, the possible relationship between abnormalities in stress and neuroimmune signaling within the cortex of people with psychotic illness has not been defined. To test the hypothesis that combined alterations in brain stress responsiveness and neuroimmune/inflammatory status are characteristic of some individuals suffering from major mental illness, we examined gene expression in the Stanley Array Cohort of 35 controls, 35 individuals with schizophrenia and 34 individuals with bipolar disorder. We used levels of 8 inflammatory-related transcripts, of which SERPINA3 was significantly elevated in individuals with schizophrenia (F(2,88)=4.137, P<0.05), and 12 glucocorticoid receptor signaling (stress) pathway transcripts previously examined, to identify two clusters of individuals: a high inflammation/stress group (n=32) and a low (n=68) inflammation/stress group. The high inflammation/stress group has a significantly greater number of individuals with schizophrenia (n=15), and a trend toward having more bipolar disorder individuals (n=11), when compared with controls (n=6). Using these subgroups, we tested which microarray-assessed transcriptional changes may be associated with high inflammatory/stress groups using ingenuity analysis and found that an extended network of gene expression changes involving immune, growth factors, inhibitory signaling and cell death factors also distinguished these groups. Our work demonstrates that some of the heterogeneity in schizophrenia and bipolar disorder may be partially explained by inflammation/stress interactions, and that this biological subtype cuts across Diagnostic and Statistical Manual of Mental Disorders (DSM)-defined categories.


Assuntos
Transtorno Bipolar/imunologia , Córtex Cerebral/metabolismo , Expressão Gênica , Inflamação/imunologia , Esquizofrenia/imunologia , Estresse Psicológico/imunologia , Adulto , Biomarcadores/metabolismo , Transtorno Bipolar/classificação , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/classificação , Adulto Jovem
19.
J Neuroinflammation ; 10: 152, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24330827

RESUMO

BACKGROUND: Rasmussen's encephalitis (RE) is an inflammatory encephalopathy of unknown cause defined by seizures with progressive neurological disabilities. Herein, the pathogenesis of RE was investigated focusing on inflammasome activation in the brain. METHODS: Patients with RE at the University of Alberta, Edmonton, AB, Canada, were identified and analyzed by neuroimaging, neuropsychological, molecular, and pathological tools. Primary human microglia, astrocytes, and neurons were examined using RT-PCR, enzyme-linked immunosorbent assay (ELISA), and western blotting. RESULTS: Four patients with RE were identified at the University of Alberta. Magnetic resonance imaging (MRI) disclosed increased signal intensities in cerebral white matter adjacent to cortical lesions of RE patients, accompanied by a decline in neurocognitive processing speed (P <0.05). CD3ϵ, HLA-DRA, and TNFα together with several inflammasome-associated genes (IL-1ß, IL-18, NLRP1, NLRP3, and CASP1) showed increased transcript levels in RE brains compared to non-RE controls (n = 6; P <0.05). Cultured human microglia displayed expression of inflammasome-associated genes and responded to inflammasome activators by releasing IL-1ß, which was inhibited by the caspase inhibitor, zVAD-fmk. Major histocompatibility complex (MHC) class II, IL-1ß, caspase-1, and alanine/serine/cysteine (ASC) immunoreactivity were increased in RE brain tissues, especially in white matter myeloid cells, in conjunction with mononuclear cell infiltration and gliosis. Neuroinflammation in RE brains was present in both white matter and adjacent cortex with associated induction of inflammasome components, which was correlated with neuroimaging and neuropsychological deficits. CONCLUSION: Inflammasome activation likely contributes to the disease process underlying RE and offers a mechanistic target for future therapeutic interventions.


Assuntos
Encéfalo/imunologia , Encéfalo/fisiopatologia , Encefalite/imunologia , Encefalite/fisiopatologia , Inflamassomos/fisiologia , Adolescente , Western Blotting , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Hum Mol Genet ; 22(20): 4053-63, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23727838

RESUMO

Human cortical malformations, including lissencephaly, polymicrogyria and other diseases of neurodevelopment, have been associated with mutations in microtubule subunits and microtubule-associated proteins. Here we report our cloning of the brain dimple (brdp) mouse mutation, which we recovered from an ENU screen for recessive perinatal phenotypes affecting neurodevelopment. We identify the causal mutation in the tubulin, beta-2b (Tubb2b) gene as a missense mutation at a highly conserved residue (N247S). Brdp/brdp homozygous mutants have significant thinning of the cortical epithelium, which is markedly more severe in the caudo-lateral portion of the telencephalon, and do not survive past birth. The cortical defects are largely due to a major increase in apoptosis and we note abnormal proliferation of the basal progenitors. Adult brdp/+ mice are viable and fertile but exhibit behavioral phenotypes. This allele of Tubb2b represents the most severely affected mouse tubulin phenotype reported to date and this is the first report of a tubulin mutation affecting neuronal proliferation and survival.


Assuntos
Córtex Cerebral/anormalidades , Genes Letais , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/patologia , Mutação de Sentido Incorreto , Tubulina (Proteína)/genética , Animais , Encéfalo/anormalidades , Encéfalo/embriologia , Encéfalo/metabolismo , Proliferação de Células , Sobrevivência Celular , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Clonagem Molecular , Evolução Molecular , Feminino , Humanos , Masculino , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Células NIH 3T3 , Neurônios/fisiologia , Fenótipo , Conformação Proteica , Alinhamento de Sequência , Tubulina (Proteína)/química
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