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1.
Cell ; 185(12): 2184-2199.e16, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35649412

RESUMO

The factors driving therapy resistance in diffuse glioma remain poorly understood. To identify treatment-associated cellular and genetic changes, we analyzed RNA and/or DNA sequencing data from the temporally separated tumor pairs of 304 adult patients with isocitrate dehydrogenase (IDH)-wild-type and IDH-mutant glioma. Tumors recurred in distinct manners that were dependent on IDH mutation status and attributable to changes in histological feature composition, somatic alterations, and microenvironment interactions. Hypermutation and acquired CDKN2A deletions were associated with an increase in proliferating neoplastic cells at recurrence in both glioma subtypes, reflecting active tumor growth. IDH-wild-type tumors were more invasive at recurrence, and their neoplastic cells exhibited increased expression of neuronal signaling programs that reflected a possible role for neuronal interactions in promoting glioma progression. Mesenchymal transition was associated with the presence of a myeloid cell state defined by specific ligand-receptor interactions with neoplastic cells. Collectively, these recurrence-associated phenotypes represent potential targets to alter disease progression.


Assuntos
Neoplasias Encefálicas , Glioma , Microambiente Tumoral , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Evolução Molecular , Genes p16 , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Mutação , Recidiva Local de Neoplasia
2.
J Neurosci ; 44(6)2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38148152

RESUMO

The functional connectome supports information transmission through the brain at various spatial scales, from exchange between broad cortical regions to finer-scale, vertex-wise connections that underlie specific information processing mechanisms. In adults, while both the coarse- and fine-scale functional connectomes predict cognition, the fine scale can predict up to twice the variance as the coarse-scale functional connectome. Yet, past brain-wide association studies, particularly using large developmental samples, focus on the coarse connectome to understand the neural underpinnings of individual differences in cognition. Using a large cohort of children (age 9-10 years; n = 1,115 individuals; both sexes; 50% female, including 170 monozygotic and 219 dizygotic twin pairs and 337 unrelated individuals), we examine the reliability, heritability, and behavioral relevance of resting-state functional connectivity computed at different spatial scales. We use connectivity hyperalignment to improve access to reliable fine-scale (vertex-wise) connectivity information and compare the fine-scale connectome with the traditional parcel-wise (coarse scale) functional connectomes. Though individual differences in the fine-scale connectome are more reliable than those in the coarse-scale, they are less heritable. Further, the alignment and scale of connectomes influence their ability to predict behavior, whereby some cognitive traits are equally well predicted by both connectome scales, but other, less heritable cognitive traits are better predicted by the fine-scale connectome. Together, our findings suggest there are dissociable individual differences in information processing represented at different scales of the functional connectome which, in turn, have distinct implications for heritability and cognition.


Assuntos
Conectoma , Humanos , Masculino , Adulto , Criança , Feminino , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Cognição
3.
Nature ; 576(7785): 112-120, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31748746

RESUMO

The evolutionary processes that drive universal therapeutic resistance in adult patients with diffuse glioma remain unclear1,2. Here we analysed temporally separated DNA-sequencing data and matched clinical annotation from 222 adult patients with glioma. By analysing mutations and copy numbers across the three major subtypes of diffuse glioma, we found that driver genes detected at the initial stage of disease were retained at recurrence, whereas there was little evidence of recurrence-specific gene alterations. Treatment with alkylating agents resulted in a hypermutator phenotype at different rates across the glioma subtypes, and hypermutation was not associated with differences in overall survival. Acquired aneuploidy was frequently detected in recurrent gliomas and was characterized by IDH mutation but without co-deletion of chromosome arms 1p/19q, and further converged with acquired alterations in the cell cycle and poor outcomes. The clonal architecture of each tumour remained similar over time, but the presence of subclonal selection was associated with decreased survival. Finally, there were no differences in the levels of immunoediting between initial and recurrent gliomas. Collectively, our results suggest that the strongest selective pressures occur during early glioma development and that current therapies shape this evolution in a largely stochastic manner.


Assuntos
Glioma/genética , Adulto , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 19 , Progressão da Doença , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Mutação , Polimorfismo de Nucleotídeo Único , Recidiva
4.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33622790

RESUMO

Human cortex is patterned by a complex and interdigitated web of large-scale functional networks. Recent methodological breakthroughs reveal variation in the size, shape, and spatial topography of cortical networks across individuals. While spatial network organization emerges across development, is stable over time, and is predictive of behavior, it is not yet clear to what extent genetic factors underlie interindividual differences in network topography. Here, leveraging a nonlinear multidimensional estimation of heritability, we provide evidence that individual variability in the size and topographic organization of cortical networks are under genetic control. Using twin and family data from the Human Connectome Project (n = 1,023), we find increased variability and reduced heritability in the size of heteromodal association networks (h2 : M = 0.34, SD = 0.070), relative to unimodal sensory/motor cortex (h2 : M = 0.40, SD = 0.097). We then demonstrate that the spatial layout of cortical networks is influenced by genetics, using our multidimensional estimation of heritability (h2-multi; M = 0.14, SD = 0.015). However, topographic heritability did not differ between heteromodal and unimodal networks. Genetic factors had a regionally variable influence on brain organization, such that the heritability of network topography was greatest in prefrontal, precuneus, and posterior parietal cortex. Taken together, these data are consistent with relaxed genetic control of association cortices relative to primary sensory/motor regions and have implications for understanding population-level variability in brain functioning, guiding both individualized prediction and the interpretation of analyses that integrate genetics and neuroimaging.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/metabolismo , Conectoma , Humanos , Imageamento por Ressonância Magnética , Modelos Teóricos
5.
Proc Natl Acad Sci U S A ; 117(40): 25138-25149, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32958675

RESUMO

Major depressive disorder emerges from the complex interactions of biological systems that span genes and molecules through cells, networks, and behavior. Establishing how neurobiological processes coalesce to contribute to depression requires a multiscale approach, encompassing measures of brain structure and function as well as genetic and cell-specific transcriptional data. Here, we examine anatomical (cortical thickness) and functional (functional variability, global brain connectivity) correlates of depression and negative affect across three population-imaging datasets: UK Biobank, Brain Genomics Superstruct Project, and Enhancing NeuroImaging through Meta Analysis (ENIGMA; combined n ≥ 23,723). Integrative analyses incorporate measures of cortical gene expression, postmortem patient transcriptional data, depression genome-wide association study (GWAS), and single-cell gene transcription. Neuroimaging correlates of depression and negative affect were consistent across three independent datasets. Linking ex vivo gene down-regulation with in vivo neuroimaging, we find that transcriptional correlates of depression imaging phenotypes track gene down-regulation in postmortem cortical samples of patients with depression. Integrated analysis of single-cell and Allen Human Brain Atlas expression data reveal somatostatin interneurons and astrocytes to be consistent cell associates of depression, through both in vivo imaging and ex vivo cortical gene dysregulation. Providing converging evidence for these observations, GWAS-derived polygenic risk for depression was enriched for genes expressed in interneurons, but not glia. Underscoring the translational potential of multiscale approaches, the transcriptional correlates of depression-linked brain function and structure were enriched for disorder-relevant molecular pathways. These findings bridge levels to connect specific genes, cell classes, and biological pathways to in vivo imaging correlates of depression.


Assuntos
Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Transtorno Depressivo Maior/genética , Regulação da Expressão Gênica/genética , Somatostatina/genética , Astrócitos/metabolismo , Astrócitos/patologia , Autopsia , Encéfalo/patologia , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/fisiopatologia , Feminino , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Redes Reguladoras de Genes/genética , Estudo de Associação Genômica Ampla , Genômica/métodos , Humanos , Interneurônios/metabolismo , Interneurônios/patologia , Masculino , Herança Multifatorial/genética , Neuroimagem/métodos , Transdução de Sinais/genética , Análise de Célula Única/métodos
6.
Neuroimage ; 260: 119485, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35843514

RESUMO

Individual differences in brain anatomy can be used to predict variations in cognitive ability. Most studies to date have focused on broad population-level trends, but the extent to which the observed predictive features are shared across sexes and age groups remains to be established. While it is standard practice to account for intracranial volume (ICV) using proportion correction in both regional and whole-brain morphometric analyses, in the context of brain-behavior predictions the possible differential impact of ICV correction on anatomical features and subgroups within the population has yet to be systematically investigated. In this work, we evaluate the effect of proportional ICV correction on sex-independent and sex-specific predictive models of individual cognitive abilities across multiple anatomical properties (surface area, gray matter volume, and cortical thickness) in healthy young adults (Human Connectome Project; n = 1013, 548 females) and typically developing children (Adolescent Brain Cognitive Development study; n = 1823, 979 females). We demonstrate that ICV correction generally reduces predictive accuracies derived from surface area and gray matter volume, while increasing predictive accuracies based on cortical thickness in both adults and children. Furthermore, the extent to which predictive models generalize across sexes and age groups depends on ICV correction: models based on surface area and gray matter volume are more generalizable without ICV correction, while models based on cortical thickness are more generalizable with ICV correction. Finally, the observed neuroanatomical features predictive of cognitive abilities are unique across age groups regardless of ICV correction, but whether they are shared or unique across sexes (within age groups) depends on ICV correction. These findings highlight the importance of considering individual differences in ICV, and show that proportional ICV correction does not remove the effects of cranial volume from anatomical measurements and can introduce ICV bias where previously there was none. ICV correction choices affect not just the strength of the relationships captured, but also the conclusions drawn regarding the neuroanatomical features that underlie those relationships.


Assuntos
Córtex Cerebral , Imageamento por Ressonância Magnética , Adolescente , Viés , Encéfalo/diagnóstico por imagem , Córtex Cerebral/anatomia & histologia , Criança , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino , Adulto Jovem
7.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361784

RESUMO

Irrespective of the many strategies focused on dealing with spinal cord injury (SCI), there is still no way to restore motor function efficiently or an adequate regenerative therapy. One promising method that could potentially prove highly beneficial for rehabilitation in patients is to re-engage specific neuronal populations of the spinal cord following SCI. Targeted activation may maintain and strengthen existing neuronal connections and/or facilitate the reorganization and development of new connections. BioLuminescent-OptoGenetics (BL-OG) presents an avenue to non-invasively and specifically stimulate neurons; genetically targeted neurons express luminopsins (LMOs), light-emitting luciferases tethered to light-sensitive channelrhodopsins that are activated by adding the luciferase substrate coelenterazine (CTZ). This approach employs ion channels for current conduction while activating the channels through treatment with the small molecule CTZ, thus allowing non-invasive stimulation of all targeted neurons. We previously showed the efficacy of this approach for improving locomotor recovery following severe spinal cord contusion injury in rats expressing the excitatory luminopsin 3 (LMO3) under control of a pan-neuronal and motor-neuron-specific promoter with CTZ applied through a lateral ventricle cannula. The goal of the present study was to test a new generation of LMOs based on opsins with higher light sensitivity which will allow for peripheral delivery of the CTZ. In this construct, the slow-burn Gaussia luciferase variant (sbGLuc) is fused to the opsin CheRiff, creating LMO3.2. Taking advantage of the high light sensitivity of this opsin, we stimulated transduced lumbar neurons after thoracic SCI by intraperitoneal application of CTZ, allowing for a less invasive treatment. The efficacy of this non-invasive BioLuminescent-OptoGenetic approach was confirmed by improved locomotor function. This study demonstrates that peripheral delivery of the luciferin CTZ can be used to activate LMOs expressed in spinal cord neurons that employ an opsin with increased light sensitivity.


Assuntos
Optogenética , Traumatismos da Medula Espinal , Animais , Ratos , Optogenética/métodos , Fotofobia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Opsinas/genética , Medula Espinal , Luciferases/genética , Recuperação de Função Fisiológica/fisiologia
8.
Educ Prim Care ; 33(5): 288-295, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35770614

RESUMO

Covid-19 has altered medical education worldwide. Given recent events, UK Longitudinal Integrated Clerkships (LICs), which are relatively new innovations, may have changed in structure and delivery, or may have demonstrated resilience. Collating the responses and experiences of UK institutions may yield transferrable recommendations for institutions wishing to develop sustainable LICs. A mixed-methods survey concerning LIC prevalence, variety, and experiences of responses to Covid-19 was circulated to all 33 UK medical schools through academic networks. 25 survey responses were received, representing 20 institutions. 12 faculty completed follow up semi-structured interviews. 13 LICs were reported: 1 wasn't running during 2020, 5 were running unchanged, and 7 with alterations. 2 additional LICs were planned. Thematic analysis of free-text survey and interview responses revealed that relationships between faculty and institutions were central in facilitating recent adaptations to UK LICs. Given model flexibility, an increased drive to develop LICs was also evident. Barriers to adapting programmes included uncertainty regarding progression of Covid-19 restrictions and issues with secondary care access. Investing in faculty development and support networks could increase LIC sustainability. By highlighting the relative resilience of UK LIC placements during Covid-19, these findings offer important insight for the future delivery of sustainable LICs within, and beyond, the UK.


Assuntos
COVID-19 , Estágio Clínico , Educação de Graduação em Medicina , Estudantes de Medicina , COVID-19/epidemiologia , Estágio Clínico/métodos , Educação de Graduação em Medicina/métodos , Humanos , Faculdades de Medicina , Reino Unido/epidemiologia
9.
J Neurosci ; 40(26): 5090-5104, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32451322

RESUMO

Working memory function changes across development and varies across individuals. The patterns of behavior and brain function that track individual differences in working memory during human development, however, are not well understood. Here, we establish associations between working memory, other cognitive abilities, and functional MRI (fMRI) activation in data from over 11,500 9- to 10-year-old children (both sexes) enrolled in the Adolescent Brain Cognitive Development (ABCD) Study, an ongoing longitudinal study in the United States. Behavioral analyses reveal robust relationships between working memory, short-term memory, language skills, and fluid intelligence. Analyses relating out-of-scanner working memory performance to memory-related fMRI activation in an emotional n-back task demonstrate that frontoparietal activity during a working memory challenge indexes working memory performance. This relationship is domain specific, such that fMRI activation related to emotion processing during the emotional n-back task, inhibitory control during a stop-signal task (SST), and reward processing during a monetary incentive delay (MID) task does not track memory abilities. Together, these results inform our understanding of individual differences in working memory in childhood and lay the groundwork for characterizing the ways in which they change across adolescence.SIGNIFICANCE STATEMENT Working memory is a foundational cognitive ability that changes over time and varies across individuals. Here, we analyze data from over 11,500 9- to 10-year-olds to establish relationships between working memory, other cognitive abilities, and frontoparietal brain activity during a working memory challenge, but not during other cognitive challenges. Our results lay the groundwork for assessing longitudinal changes in working memory and predicting later academic and other real-world outcomes.


Assuntos
Encéfalo/fisiologia , Desenvolvimento Infantil/fisiologia , Memória de Curto Prazo/fisiologia , Encéfalo/crescimento & desenvolvimento , Criança , Feminino , Humanos , Individualidade , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino
10.
Neuroimage ; 244: 118602, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563679

RESUMO

The adaptive adjustment of behavior in pursuit of desired goals is critical for survival. To accomplish this complex feat, individuals must weigh the potential benefits of a given action against time, energy, and resource costs. Here, we examine brain responses associated with willingness to exert physical effort during the sustained pursuit of desired goals. Our analyses reveal a distributed pattern of brain activity in aspects of ventral medial prefrontal cortex that tracks with trial-level variability in effort expenditure. Indicating the brain represents echoes of effort at the point of feedback, whole-brain searchlights identified signals reflecting past effort expenditure in medial and lateral prefrontal cortices, encompassing broad swaths of frontoparietal and dorsal attention networks. These data have important implications for our understanding of how the brain's valuation mechanisms contend with the complexity of real-world dynamic environments with relevance for the study of behavior across health and disease.


Assuntos
Objetivos , Esforço Físico/fisiologia , Córtex Pré-Frontal/fisiologia , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Motivação , Adulto Jovem
11.
Educ Prim Care ; 32(3): 140-148, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32898461

RESUMO

Longitudinal integrated clerkships (LICs) are increasingly available within the United Kingdom, but gaps in knowledge remain regarding their efficacy and the influence of local context. In 2019-20, the Hull York Medical School ran a pilot LIC for 6 fourth-year medical students. This work describes the longitudinal qualitative programme evaluation. LIC students participated in two focus groups, one after four months, and another at the end of the programme. In total, 16 faculty were also interviewed regarding their experiences in developing, implementing and running the LIC. Students' GP supervisors were difficult to engage in detailed evaluation due to the COVID-19 pandemic, and so were briefly surveyed at the end of the LIC. All data were pooled and analysed together using reflexive thematic analysis. Two major themes were identified: 'Trajectory of the LIC', describing the learning curve students and faculty encounter, and 'Institutional decision making', describing the need for clarity regarding the programme's purpose. The programme was largely positively received, but areas for improvement locally, and transferrable recommendations, were identified. Aligning assessment to programme aims is an important area for future development, alongside balancing structured with unstructured time, and supporting students as they navigate a J-shaped learning curve.


Assuntos
Estágio Clínico/organização & administração , Educação de Graduação em Medicina/métodos , Medicina Geral/métodos , Adulto , COVID-19 , Inglaterra , Docentes de Medicina , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Estudantes de Medicina/psicologia
12.
Mol Phylogenet Evol ; 143: 106688, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31747540

RESUMO

Leeches of the family Erpobdellidae are important members of benthic freshwater environments, where they are voracious predators of other invertebrates and an important source of nutrition for several species of vertebrates. Beset by a lack of reliable diagnostic morphological characters and destructive identification processes, molecular approaches have, in recent years, been employed to illuminate the relationships within this family, and DNA barcoding has been employed for identification purposes. However, an understanding of the levels of genetic variation across the geographic distributions of members of the genus is still lacking. Herein, we sequence the mitochondrial COI locus for 249 newly collected North American individuals, representing 5 species, as well as mitochondrial 12S rDNA, nuclear 18S rDNA, and nuclear 28S rDNA for a select subset of these. Our COI dataset was leveraged to detect potential cryptic species, and to calculate genetic distances as a proxy for the degree of gene flow between populations. Augmented by numerous sequences from GenBank, the multilocus dataset was used to reconstruct a phylogenetic hypothesis for worldwide members of the genus. Beyond corroborating previous overarching phylogenetic frameworks, our results show that an undescribed species that is morphologically and genetically similar to Erpobdella punctata exists in sympatry with this species - the new species has likely been overlooked in previous studies due to its morphological similarity with Erpobdella punctata. Erpobdella bucera is reported from Canada for the first time; and Erpobdella microstoma is newly reported from Saskatchewan and placed in a phylogeny for the first time. Finally, we find evidence for genetic structure in both E. cf. punctata and Erpobdella obscura that is correlated with major river drainage basin boundaries in North America.


Assuntos
Anelídeos/genética , Variação Genética , Animais , Anelídeos/classificação , Biodiversidade , Canadá , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Haplótipos , Mitocôndrias/genética , Filogenia , RNA Ribossômico/classificação , RNA Ribossômico/genética
14.
Cereb Cortex ; 29(8): 3496-3504, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-30215680

RESUMO

People who score higher on intelligence tests tend to have larger brains. Twin studies suggest the same genetic factors influence both brain size and intelligence. This has led to the hypothesis that genetics influence intelligence partly by contributing to the development of larger brains. We tested this hypothesis using four large imaging genetics studies (combined N = 7965) with polygenic scores derived from a genome-wide association study (GWAS) of educational attainment, a correlate of intelligence. We conducted meta-analysis to test associations among participants' genetics, total brain volume (i.e., brain size), and cognitive test performance. Consistent with previous findings, participants with higher polygenic scores achieved higher scores on cognitive tests, as did participants with larger brains. Participants with higher polygenic scores also had larger brains. We found some evidence that brain size partly mediated associations between participants' education polygenic scores and their cognitive test performance. Effect sizes were larger in the population-based samples than in the convenience-based samples. Recruitment and retention of population-representative samples should be a priority for neuroscience research. Findings suggest promise for studies integrating GWAS discoveries with brain imaging to understand neurobiology linking genetics with cognitive performance.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição , Escolaridade , Inteligência/genética , Adolescente , Adulto , Idoso , Encéfalo/anatomia & histologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Nova Zelândia , Tamanho do Órgão , Reino Unido , Estados Unidos , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 114(20): 5247-5252, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28461466

RESUMO

To provide new preclinical evidence toward improving the efficacy of oxytocin (OT) in treating social dysfunction, we tested the benefit of administering OT under simultaneously induced opioid antagonism during dyadic gaze interactions in monkeys. OT coadministered with a µ-opioid receptor antagonist, naloxone, invoked a supralinear enhancement of prolonged and selective social attention, producing a stronger effect than the summed effects of each administered separately. These effects were consistently observed when averaging over entire sessions, as well as specifically following events of particular social importance, including mutual eye contact and mutual reward receipt. Furthermore, attention to various facial regions was differentially modulated depending on social context. Using the Allen Institute's transcriptional atlas, we further established the colocalization of µ-opioid and κ-opioid receptor genes and OT genes at the OT-releasing sites in the human brain. These data across monkeys and humans support a regulatory relationship between the OT and opioid systems and suggest that administering OT under opioid antagonism may boost the therapeutic efficacy of OT for enhancing social cognition.


Assuntos
Fixação Ocular/efeitos dos fármacos , Ocitocina/metabolismo , Ocitocina/farmacologia , Analgésicos Opioides/antagonistas & inibidores , Animais , Atenção/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Feminino , Macaca mulatta/fisiologia , Masculino , Naloxona/metabolismo , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Receptores Opioides kappa , Receptores Opioides mu/efeitos dos fármacos , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Comportamento Social
16.
J Dairy Res ; 87(3): 298-305, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32398175

RESUMO

We evaluated the effects of chronic subclinical mastitis (CSM) caused by different types of pathogens on milk yield and milk components at the cow level. A total of 388 Holstein cows had milk yield measured and were milk sampled three times at intervals of two weeks for determination of SCC and milk composition, and microbiological culture was performed. Cows were considered healthy if all three samples of SCC were ≤200 000 cells/ml and were culture-negative at the third milk sampling. Cows with one result of SCC > 200 000 cells/ml were considered to suffer non-chronic subclinical mastitis whereas cows with at least 2 out of 3 results of SCC > 200 000 cells/ml had CSM. These latter cows were further sorted according to culture results into chronic negative-culture or chronic positive-culture. This resulted in four udder health statuses: healthy, non-chronic, chronicNC or chronicPC. The milk and components yields were evaluated according to the udder health status and by pathogen using a linear mixed effects model. A total of 134 out of 388 cows (34.5%) were chronicPC, 57 cows (14.7%) were chronicNC, 78 cows (20.1%) were non-chronic and 119 cows (30.7%) were considered healthy, which resulted in a grand total of 1164 cow records included in the statistical model. The healthy cows produced more milk than each of the other groups (+2.1 to +5.7 kg/cow/day) and produced higher milk component yields than the chronicPC cows. The healthy cows produced more milk than cows with chronicPC caused by minor (+5.2 kg/cow/day) and major pathogens (+7.1 kg/cow/day) and losses varied from 5.8 to 11.8 kg/cow/day depending on the pathogen causing chronicPC mastitis. Chronic positive-culture cows had a reduction of at least 24.5% of milk yield and 22.4% of total solids yield.


Assuntos
Infecções Bacterianas/veterinária , Lactação , Mastite Bovina/diagnóstico , Leite , Animais , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Bovinos , Doença Crônica , Feminino , Mastite Bovina/microbiologia , Mastite Bovina/patologia
17.
Ann Surg Oncol ; 25(5): 1425-1431, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29500765

RESUMO

PURPOSE: Adrenocortical carcinoma (ACC) is a rare, aggressive cancer; complete surgical resection offers the best chance for long-term survival. The impact of surgical margin status on survival is poorly understood. Our objective was to determine the association of margin status with survival. METHODS: Patients with ACC were identified from the National Cancer Data Base, 1998-2012, and stratified based on surgical margin status (negative vs. microscopically positive [+] vs. macroscopically [+]). Univariate/multivariate regression/survival analyses were utilized to determine factors associated with margin status and overall survival (OS). RESULTS: A total of 1553 patients underwent surgery at 589 institutions: 86% had negative, 12% microscopically (+), and 2% macroscopically (+) margins. Those with microscopically (+) and macroscopically (+) margins more often received adjuvant chemotherapy (39.4% macroscopically (+) vs. 38.5% microscopically (+) vs. 25.2% negative margins, p < 0.001). For unadjusted analysis, there was a significant difference in OS between the groups (log-rank p < 0.001), with median survival times of 58 months (95% confidence interval [CI] 49-66) for those with negative margins, 22 months (95% CI 18-34) microscopically (+), and 14 months (95% CI 6-27) macroscopically (+) margins. After adjustment, both microscopically (+) (HR 1.76, p < 0.001) and macroscopically (+) (HR 2.10, p = 0.0019) margin status were associated with compromised survival. CONCLUSIONS: Having micro- or macroscopically (+) margin status after ACC resection is associated with dose-dependent compromised survival. These results underscore the importance of achieving negative surgical margins for optimizing long-term patient outcomes.


Assuntos
Neoplasias do Córtex Suprarrenal/cirurgia , Carcinoma Adrenocortical/cirurgia , Margens de Excisão , Adulto , Idoso , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Estudos Retrospectivos , Taxa de Sobrevida
18.
Eur Radiol ; 28(1): 235-242, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28710575

RESUMO

OBJECTIVES: To assess the performance of the "Computer-Aided Nodule Assessment and Risk Yield" (CANARY) software in the differentiation and risk assessment of histological subtypes of lung adenocarcinomas manifesting as pure ground glass nodules on computed tomography (CT). METHODS: 64 surgically resected and histologically proven adenocarcinomas manifesting as pure ground-glass nodules on CT were assessed using CANARY software, which classifies voxel-densities into three risk components (low, intermediate, and high risk). Differences in risk components between histological adenocarcinoma subtypes were analysed. To determine the optimal threshold reflecting the presence of an invasive focus, sensitivity, specificity, negative predictive value, and positive predictive value were calculated. RESULTS: 28/64 (44%) were adenocarcinomas in situ (AIS); 26/64 (41%) were minimally invasive adenocarcinomas (MIA); and 10/64 (16%) were invasive ACs (IAC). The software showed significant differences in risk components between histological subtypes (P<0.001-0.003). A relative volume of 45% or less of low-risk components was associated with histological invasiveness (specificity 100%, positive predictive value 100%). CONCLUSIONS: CANARY-based risk assessment of ACs manifesting as pure ground glass nodules on CT allows the differentiation of their histological subtypes. A threshold of 45% of low-risk components reflects invasiveness in these groups. KEY POINTS: • CANARY-based risk assessment allows the differentiation of their histological subtypes. • 45% or less of low-risk component reflects histological invasiveness. • CANARY has potential role in suspected adenocarcinomas manifesting as pure ground-glass nodules.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Diagnóstico por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma de Pulmão , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade
19.
Fam Pract ; 35(4): 511-516, 2018 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-29309587

RESUMO

Background: Primary care physicians are particularly prone to high levels of burnout and poor well-being. Despite this, no qualitative studies have specifically investigated the best ways to improve well-being and prevent burnout in primary care physicians. Previous interventions within primary care have been person-oriented and mainly focused on mindfulness, but there has been no prior research on whether general practitioners (GPs) deem this to be the best approach. Objectives: To explore strategies that could improve GP well-being and reduce or prevent burnout, based on GP perceptions of the workplace factors that affect their levels of well-being and burnout. Methods: Five focus groups were conducted, with 25 GPs (locums, salaried, trainees, and partners) in the UK, between September 2015 and February 2016. Focus groups took place in GP practices and private meeting rooms. Discussions were centered on the workplace factors that they perceived to influence their well-being, along with strategies that they use either personally, or as a practice, to try and prevent burnout. Furthermore, strategies that could feasibly be implemented by individuals and practices to improve well-being, as well as changes that are needed by groups or organizations that are external to their practice (e.g., the government) to improve the working conditions, were explored. Thematic analysis was conducted on the transcripts. Results: Based on the contributors to burnout and workplace well-being that the participants identified, the following feasible strategies were suggested: compulsory daily coffee breaks, increasing self- and organizational awareness of the risks of burnout and mentoring or buddy systems. System-level organizational changes were voiced as vital, however, to improve the well-being of all primary care physicians. Increasing resources seemed to be the ideal solution, to allow for more administrative staff and GPs. Conclusion: These strategies merit further consideration by researchers, physicians, healthcare organizations and policy makers both in the UK and beyond. Failure to do so may result in healthcare staff becoming even more burntout, potentially leading to a loss of doctors from the workforce.


Assuntos
Esgotamento Profissional/prevenção & controle , Clínicos Gerais/estatística & dados numéricos , Satisfação no Emprego , Carga de Trabalho/psicologia , Local de Trabalho/psicologia , Atitude do Pessoal de Saúde , Feminino , Grupos Focais , Clínicos Gerais/psicologia , Humanos , Masculino , Atenção Primária à Saúde , Pesquisa Qualitativa , Reino Unido
20.
Adv Physiol Educ ; 42(1): 21-25, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29341811

RESUMO

The impact of distance education via interactive videoconferencing on pharmacy students' performance in a course was assessed after implementation of a distance campus. Students filled out a "Student Demographic Survey" and a "Precourse Knowledge Assessment" at the start of the course and a "Postcourse Knowledge Assessment" and a "Postcourse Student Perceptions Survey" at the end of the course. The primary end point, a comparison of course grades (%) between the main and distance campuses, was examined using the two-sample t-test. We examined the relationships among demographics, campus location, course grades, grade point average, pre- and postcourse knowledge assessments, and postcourse perceptions as our secondary end points with parametric and nonparametric tests. Data from 93 students were included in the analysis [main campus ( n = 81); distance campus ( n = 12)]. Students on the main campus achieved a significantly higher final course grade (87 vs. 81%; P = 0.02). Scores on the Postcourse Knowledge Assessment were also significantly higher compared with those of students on the distance education campus (77 vs. 68%; P = 0.04). Students on both campuses reported self-perceived improvement in their knowledge base regarding various aspects of infectious diseases. Compared with the students on the distance campus, those on the main campus were more likely to subjectively perceive that they had succeeded in the course ( P = 0.04). Our study suggests that students on the main campus achieved a higher final course grade and were more likely to feel that they had succeeded in the course. Students on both campuses reported improvement in knowledge.


Assuntos
Educação a Distância/métodos , Educação em Farmácia/métodos , Avaliação Educacional/métodos , Treinamento por Simulação/métodos , Estudantes de Farmácia , Comunicação por Videoconferência , Adulto , Educação a Distância/tendências , Educação em Farmácia/tendências , Feminino , Humanos , Masculino , Satisfação Pessoal , Treinamento por Simulação/tendências , Comunicação por Videoconferência/tendências
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