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1.
Asia Pac Policy Stud ; 9(1): 5-22, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35441033

RESUMO

The Chinese Communist Party is consolidating one party rule under the leadership of Xi Jinping. Beijing seeks to rule by central mandate while limiting local autonomy. The central government response to the COVID-19 public health emergency reinforces this view. In January 2020 Beijing established the Central Epidemic Response Leading Group to mobilise a comprehensive nationwide policy effort to contain the virus. The exceptional nature of the COVID-19 national emergency allows the central government to project power over local authorities and leverage over citizens, but we argue that this is a short-term phenomenon because local disease control initiatives remain important, with local authorities adapting national policies to meet constituent needs. There are degrees of policy discretion and divergence at the subnational level that enable context-specific responses to the virus within China's strict bureaucratic hierarchy. Primary data derives from interviews and observations in Nancun village, Hebei Province, conducted from January to April 2020. Evidence from Nancun explains how local authorities interpret the edicts and mandates of the central government.

2.
Sci Rep ; 12(1): 867, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042882

RESUMO

High-resolution whole-brain microscopy provides a means for post hoc determination of the location of implanted devices and labelled cell populations that are necessary to interpret in vivo experiments designed to understand brain function. Here we have developed two plugins (brainreg and brainreg-segment) for the Python-based image viewer napari, to accurately map any object in a common coordinate space. We analysed the position of dye-labelled electrode tracks and two-photon imaged cell populations expressing fluorescent proteins. The precise location of probes and cells were physiologically interrogated and revealed accurate segmentation with near-cellular resolution.


Assuntos
Microscopia
3.
Prog Biophys Mol Biol ; 168: 81-93, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34216639

RESUMO

Over the last ten years, developments in whole-brain microscopy now allow for high-resolution imaging of intact brains of small animals such as mice. These complex images contain a wealth of information, but many neuroscience laboratories do not have all of the computational knowledge and tools needed to process these data. We review recent open source tools for registration of images to atlases, and the segmentation, visualisation and analysis of brain regions and labelled structures such as neurons. Since the field lacks fully integrated analysis pipelines for all types of whole-brain microscopy analysis, we propose a pathway for tool developers to work together to meet this challenge.


Assuntos
Fenômenos Fisiológicos do Sistema Nervoso , Neurociências , Animais , Encéfalo , Processamento de Imagem Assistida por Computador , Camundongos , Microscopia
4.
Neuron ; 110(3): 532-543.e9, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34788632

RESUMO

To successfully navigate the environment, animals depend on their ability to continuously track their heading direction and speed. Neurons that encode angular head velocity (AHV) are fundamental to this process, yet the contribution of various motion signals to AHV coding in the cortex remains elusive. By performing chronic single-unit recordings in the retrosplenial cortex (RSP) of the mouse and tracking the activity of individual AHV cells between freely moving and head-restrained conditions, we find that vestibular inputs dominate AHV signaling. Moreover, the addition of visual inputs onto these neurons increases the gain and signal-to-noise ratio of their tuning during active exploration. Psychophysical experiments and neural decoding further reveal that vestibular-visual integration increases the perceptual accuracy of angular self-motion and the fidelity of its representation by RSP ensembles. We conclude that while cortical AHV coding requires vestibular input, where possible, it also uses vision to optimize heading estimation during navigation.


Assuntos
Percepção de Movimento , Vestíbulo do Labirinto , Animais , Giro do Cíngulo/fisiologia , Movimentos da Cabeça/fisiologia , Camundongos , Percepção de Movimento/fisiologia , Neurônios/fisiologia , Vestíbulo do Labirinto/fisiologia
5.
PLoS Comput Biol ; 17(5): e1009074, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34048426

RESUMO

Understanding the function of the nervous system necessitates mapping the spatial distributions of its constituent cells defined by function, anatomy or gene expression. Recently, developments in tissue preparation and microscopy allow cellular populations to be imaged throughout the entire rodent brain. However, mapping these neurons manually is prone to bias and is often impractically time consuming. Here we present an open-source algorithm for fully automated 3D detection of neuronal somata in mouse whole-brain microscopy images using standard desktop computer hardware. We demonstrate the applicability and power of our approach by mapping the brain-wide locations of large populations of cells labeled with cytoplasmic fluorescent proteins expressed via retrograde trans-synaptic viral infection.


Assuntos
Algoritmos , Encéfalo/diagnóstico por imagem , Conjuntos de Dados como Assunto , Aprendizado Profundo , Animais , Encéfalo/citologia , Camundongos
6.
Sci Rep ; 11(1): 4983, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654118

RESUMO

Quantitatively comparing brain-wide connectivity of different types of neuron is of vital importance in understanding the function of the mammalian cortex. Here we have designed an analytical approach to examine and compare datasets from hierarchical segmentation ontologies, and applied it to long-range presynaptic connectivity onto excitatory and inhibitory neurons, mainly located in layer 2/3 (L2/3), of mouse primary visual cortex (V1). We find that the origins of long-range connections onto these two general cell classes-as well as their proportions-are quite similar, in contrast to the inputs on to a cell type in L6. These anatomical data suggest that distal inputs received by the general excitatory and inhibitory classes of neuron in L2/3 overlap considerably.


Assuntos
Neurônios/fisiologia , Córtex Visual Primário , Sinapses/fisiologia , Animais , Camundongos , Camundongos Transgênicos , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Córtex Visual Primário/anatomia & histologia , Córtex Visual Primário/fisiologia
7.
Elife ; 102021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33739286

RESUMO

Three-dimensional (3D) digital brain atlases and high-throughput brain-wide imaging techniques generate large multidimensional datasets that can be registered to a common reference frame. Generating insights from such datasets depends critically on visualization and interactive data exploration, but this a challenging task. Currently available software is dedicated to single atlases, model species or data types, and generating 3D renderings that merge anatomically registered data from diverse sources requires extensive development and programming skills. Here, we present brainrender: an open-source Python package for interactive visualization of multidimensional datasets registered to brain atlases. Brainrender facilitates the creation of complex renderings with different data types in the same visualization and enables seamless use of different atlas sources. High-quality visualizations can be used interactively and exported as high-resolution figures and animated videos. By facilitating the visualization of anatomically registered data, brainrender should accelerate the analysis, interpretation, and dissemination of brain-wide multidimensional data.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Neuroimagem/métodos , Encéfalo , Software
8.
Asia Eur J ; 19(2): 189-208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33488320

RESUMO

There are persistent tensions of both a technical and political nature between Southeast Asia's two major palm oil producers, Indonesia and Malaysia, and the sustainability governance mechanisms shaping global environmental and trade standards emerging from Europe. The establishment of the national Indonesian Sustainable Palm Oil (ISPO) certification standard in 2011 is a sign of discontent with the transnational Roundtable on Sustainable Palm Oil (RSPO) regime, sparking debate about the legitimacy of private governance models initiated by non-governmental organizations and companies in Europe. This article questions whether the adoption of sustainability norms by Indonesia signals normative convergence or the emergence of rival governance structures that challenge the state. Evidence suggests that elements of norm adoption and rival governance coexist in Indonesia and that ISPO certification is an ambiguous policy with degrees of internal incoherence. The ambiguous nature of ISPO certification gives rise to unresolved disputes over power and authority between various actors. This article shows how these disputes came into being by framing these dynamics as part of a long historical process. Novel insights are gained by employing the state transformation framework and the concept of governance rescaling. Within this framework, we argue that the ambiguous nature of the ISPO results from complex interrelated processes of fragmentation, decentralization and the internationalization of the Indonesian state.

9.
Clin Pract Cases Emerg Med ; 4(3): 304-307, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32926672

RESUMO

INTRODUCTION: The evaluation of an unstable peripartum patient in the emergency department includes a differential diagnosis spanning multiple organ systems. Splenic artery aneurysm (SAA) is one of those rare diagnoses with potentially high morbidity and mortality. CASE SERIES: This case series explores two unusual cases of postpartum SAAs. Despite differences in presentation, both patients had a ruptured SAA. CONCLUSION: Often, SAAs are misdiagnosed. Early diagnosis is key, especially for the fetus. If the patient presents in shock, the expedited diagnosis and treatment can be lifesaving for both the mother and the fetus.

10.
Cell ; 181(7): 1596-1611.e27, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32559461

RESUMO

Oncogenic transformation is associated with profound changes in cellular metabolism, but whether tracking these can improve disease stratification or influence therapy decision-making is largely unknown. Using the iKnife to sample the aerosol of cauterized specimens, we demonstrate a new mode of real-time diagnosis, coupling metabolic phenotype to mutant PIK3CA genotype. Oncogenic PIK3CA results in an increase in arachidonic acid and a concomitant overproduction of eicosanoids, acting to promote cell proliferation beyond a cell-autonomous manner. Mechanistically, mutant PIK3CA drives a multimodal signaling network involving mTORC2-PKCζ-mediated activation of the calcium-dependent phospholipase A2 (cPLA2). Notably, inhibiting cPLA2 synergizes with fatty acid-free diet to restore immunogenicity and selectively reduce mutant PIK3CA-induced tumorigenicity. Besides highlighting the potential for metabolic phenotyping in stratified medicine, this study reveals an important role for activated PI3K signaling in regulating arachidonic acid metabolism, uncovering a targetable metabolic vulnerability that largely depends on dietary fat restriction. VIDEO ABSTRACT.


Assuntos
Ácido Araquidônico/análise , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Eicosanoides/metabolismo , Animais , Ácido Araquidônico/metabolismo , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Citosol/metabolismo , Eicosanoides/fisiologia , Ativação Enzimática , Feminino , Humanos , Metabolismo dos Lipídeos/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Redes e Vias Metabólicas/genética , Redes e Vias Metabólicas/fisiologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipases A2/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Cell Biol ; 219(6)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236513

RESUMO

How the cell rapidly and completely reorganizes its architecture when it divides is a problem that has fascinated researchers for almost 150 yr. We now know that the core regulatory machinery is highly conserved in eukaryotes, but how these multiple protein kinases, protein phosphatases, and ubiquitin ligases are coordinated in space and time to remodel the cell in a matter of minutes remains a major question. Cyclin B1-Cdk is the primary kinase that drives mitotic remodeling; here we show that it is targeted to the nuclear pore complex (NPC) by binding an acidic face of the kinetochore checkpoint protein, MAD1, where it coordinates NPC disassembly with kinetochore assembly. Localized cyclin B1-Cdk1 is needed for the proper release of MAD1 from the embrace of TPR at the nuclear pore so that it can be recruited to kinetochores before nuclear envelope breakdown to maintain genomic stability.


Assuntos
Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclina B1/metabolismo , Cinetocoros/metabolismo , Poro Nuclear/metabolismo , Transdução de Sinais/genética , Sistemas CRISPR-Cas , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Ciclina B1/genética , Éxons , Edição de Genes , Instabilidade Genômica/genética , Células HeLa , Humanos , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Espectrometria de Massas , Mutação , Membrana Nuclear/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas Nucleares/metabolismo , Ligação Proteica , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais/fisiologia , Fuso Acromático/metabolismo
12.
Sci Rep ; 9(1): 12084, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427619

RESUMO

Imaging of fixed tissue is routine in experimental neuroscience, but is limited by the depth of tissue that can be imaged using conventional methods. Optical clearing of brain tissue using hydrogel-based methods (e.g. CLARITY) allows imaging of large volumes of tissue and is rapidly becoming commonplace in the field. However, these methods suffer from a lack of standardized protocols and validation of the effect they have upon tissue morphology. We present a simple and reliable protocol for tissue clearing along with a quantitative assessment of the effect of tissue clearing upon morphology. Tissue clearing caused tissue swelling (compared to conventional methods), but this swelling was shown to be similar across spatial scales and the variation was within limits acceptable to the field. The results of many studies rely upon an assumption of uniformity in tissue swelling, and by demonstrating this quantitatively, research using these methods can be interpreted more reliably.


Assuntos
Encéfalo/ultraestrutura , Imageamento Tridimensional/métodos , Neurociências/métodos , Fixação de Tecidos/métodos , Animais , Encéfalo/efeitos dos fármacos , Hidrogéis/farmacologia , Camundongos
13.
Mol Autism ; 10: 8, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30858964

RESUMO

Background: Of the many genetic mutations known to increase the risk of autism spectrum disorder, a large proportion cluster upon synaptic proteins. One such family of presynaptic proteins are the neurexins (NRXN), and recent genetic and mouse evidence has suggested a causative role for NRXN2 in generating altered social behaviours. Autism has been conceptualised as a disorder of atypical connectivity, yet how single-gene mutations affect such connectivity remains under-explored. To attempt to address this, we have developed a quantitative analysis of microstructure and structural connectivity leveraging diffusion tensor MRI (DTI) with high-resolution 3D imaging in optically cleared (CLARITY) brain tissue in the same mouse, applied here to the Nrxn2α knockout (KO) model. Methods: Fixed brains of Nrxn2α KO mice underwent DTI using 9.4 T MRI, and diffusion properties of socially relevant brain regions were quantified. The same tissue was then subjected to CLARITY to immunolabel axons and cell bodies, which were also quantified. Results: DTI revealed increases in fractional anisotropy in the amygdala (including the basolateral nuclei), the anterior cingulate cortex, the orbitofrontal cortex and the hippocampus. Axial diffusivity of the anterior cingulate cortex and orbitofrontal cortex was significantly increased in Nrxn2α KO mice, as were tracts between the amygdala and the orbitofrontal cortex. Using CLARITY, we find significantly altered axonal orientation in the amygdala, orbitofrontal cortex and the anterior cingulate cortex, which was unrelated to cell density. Conclusions: Our findings demonstrate that deleting a single neurexin gene (Nrxn2α) induces atypical structural connectivity within socially relevant brain regions. More generally, our combined within-subject DTI and CLARITY approach presents a new, more sensitive method of revealing hitherto undetectable differences in the autistic brain.


Assuntos
Transtorno do Espectro Autista/genética , Encéfalo/diagnóstico por imagem , Proteínas do Tecido Nervoso/genética , Animais , Transtorno do Espectro Autista/diagnóstico por imagem , Imagem de Tensor de Difusão , Deleção de Genes , Imageamento Tridimensional , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Epilepsia Open ; 2(2): 214-225, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-29588950

RESUMO

Objective: Benign epilepsy with centrotemporal spikes (BECTS, also known as Rolandic epilepsy) is a common epilepsy syndrome that is associated with literacy and language impairments. The neural mechanisms of the syndrome are not known. The primary objective of this study was to test the hypothesis that functional connectivity within the language network is decreased in children with BECTS. We also tested the hypothesis that siblings of children with BECTS have similar abnormalities. Methods: Echo planar magnetic resonance (MR) imaging data were acquired from 25 children with BECTS, 12 siblings, and 20 healthy controls, at rest. After preprocessing with particular attention to intrascan motion, the mean signal was extracted from each of 90 regions of interest. Sparse, undirected graphs were constructed from adjacency matrices consisting of Spearman's rank correlation coefficients. Global and nodal graph metrics and subnetwork and pairwise connectivity were compared between groups. Results: There were no significant differences in graph metrics between groups. Children with BECTS had decreased functional connectivity relative to controls within a four-node subnetwork, which consisted of the left inferior frontal gyrus, the left superior frontal gyrus, the left supramarginal gyrus, and the right inferior parietal lobe (p = 0.04). A similar but nonsignificant decrease was also observed for the siblings. The BECTS groups had significant increases in connectivity within a five-node, five-edge frontal subnetwork. Significance: The results provide further evidence of decreased functional connectivity between key mediators of speech processing, language, and reading in children with BECTS. We hypothesize that these decreases reflect delayed lateralization of the language network and contribute to specific cognitive impairments.

15.
J Minim Invasive Gynecol ; 23(1): 126-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26260300

RESUMO

Essure is a popular method of permanent sterilization that offers a minimally invasive approach that avoids the risks of traditional sterilization procedures in the operating room. Despite the rarity of complications, there has been concern in the popular media over the safety of Essure. We describe the third reported case of systemic contact dermatitis due to the nickel component of the device, with a resolution of symptoms following surgical removal of the inserts. Despite these cases, we believe that extremely rare complications such as this should not dissuade patients from choosing this safe, effective method of sterilization.


Assuntos
Abdome/patologia , Hipersensibilidade/patologia , Histeroscopia/efeitos adversos , Níquel/efeitos adversos , Esterilização Tubária/efeitos adversos , Adulto , Feminino , Humanos , Histeroscopia/métodos , Gravidez , Salpingectomia , Esterilização Tubária/métodos , Falha de Tratamento
16.
Int J Pharm ; 494(2): 651-656, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25797056

RESUMO

The cost of 3D printing has reduced dramatically over the last few years and is now within reach of many scientific laboratories. This work presents an example of how 3D printing can be applied to the development of custom laboratory equipment that is specifically adapted for use with the novel brain tissue clearing technique, CLARITY. A simple, freely available online software tool was used, along with consumer-grade equipment, to produce a brain slicing chamber and a combined antibody staining and imaging chamber. Using standard 3D printers we were able to produce research-grade parts in an iterative manner at a fraction of the cost of commercial equipment. 3D printing provides a reproducible, flexible, simple and cost-effective method for researchers to produce the equipment needed to quickly adopt new methods.


Assuntos
Encéfalo/patologia , Microscopia de Fluorescência/instrumentação , Impressão Tridimensional/instrumentação , Software , Animais , Camundongos , Camundongos Endogâmicos C57BL
17.
Conn Med ; 73(10): 589-91, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19947057

RESUMO

Most urinary tract calculi are formed in the upper urinary tract while urethral calculi are uncommon. In young men, lower urinary tract symptoms are often due to infections and are treated with antibiotics, but unusual causes may be overlooked. We present a case of an impacted urethral calculus in an otherwise healthy young male who presented with several months of lower urinary tract symptoms.


Assuntos
Obstrução Uretral/diagnóstico por imagem , Cálculos Urinários/diagnóstico por imagem , Adulto , Cistoscopia , Humanos , Masculino , Pelve/diagnóstico por imagem , Ultrassonografia , Uretra/diagnóstico por imagem , Uretra/cirurgia , Obstrução Uretral/cirurgia , Cálculos Urinários/cirurgia
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