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1.
Cereb Cortex ; 33(11): 6543-6558, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-36734268

RESUMEN

The stability and flexibility of the functional parcellation of the cerebral cortex is fundamental to how familiar and novel information is both represented and stored. We leveraged new advances in Ca2+ sensors and microscopy to understand the dynamics of functional segmentation in the dorsal cerebral cortex. We performed wide-field Ca2+ imaging in head-fixed mice and used spatial independent component analysis (ICA) to identify independent spatial sources of Ca2+ fluorescence. The imaging data were evaluated over multiple timescales and discrete behaviors including resting, walking, and grooming. When evaluated over the entire dataset, a set of template independent components (ICs) were identified that were common across behaviors. Template ICs were present across a range of timescales, from days to 30 seconds, although with lower occurrence probability at shorter timescales, highlighting the stability of the functional segmentation. Importantly, unique ICs emerged at the shorter duration timescales that could act to transiently refine the cortical network. When data were evaluated by behavior, both common and behavior-specific ICs emerged. Each behavior is composed of unique combinations of common and behavior-specific ICs. These observations suggest that cerebral cortical functional segmentation exhibits considerable spatial stability over time and behaviors while retaining the flexibility for task-dependent reorganization.


Asunto(s)
Calcio , Neocórtex , Ratones , Animales , Neocórtex/diagnóstico por imagen , Factores de Tiempo , Imagen por Resonancia Magnética/métodos
2.
Neurobiol Dis ; 176: 105943, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36476979

RESUMEN

>2.5 million individuals in the United States suffer mild traumatic brain injuries (mTBI) annually. Mild TBI is characterized by a brief period of altered consciousness, without objective findings of anatomic injury on clinical imaging or physical deficit on examination. Nevertheless, a subset of mTBI patients experience persistent subjective symptoms and repeated mTBI can lead to quantifiable neurological deficits, suggesting that each mTBI alters neurophysiology in a deleterious manner not detected using current clinical methods. To better understand these effects, we performed mesoscopic Ca2+ imaging in mice to evaluate how mTBI alters patterns of neuronal interactions across the dorsal cerebral cortex. Spatial Independent Component Analysis (sICA) and Localized semi-Nonnegative Matrix Factorization (LocaNMF) were used to quantify changes in cerebral functional connectivity (FC). Repetitive, mild, controlled cortical impacts induce temporary neuroinflammatory responses, characterized by increased density of microglia exhibiting de-ramified morphology. These temporary neuro-inflammatory changes were not associated with compromised cognitive performance in the Barnes maze or motor function as assessed by rotarod. However, long-term alterations in functional connectivity (FC) were observed. Widespread, bilateral changes in FC occurred immediately following impact and persisted for up to 7 weeks, the duration of the experiment. Network alterations include decreases in global efficiency, clustering coefficient, and nodal strength, thereby disrupting functional interactions and information flow throughout the dorsal cerebral cortex. A subnetwork analysis shows the largest disruptions in FC were concentrated near the impact site. Therefore, mTBI induces a transient neuroinflammation, without alterations in cognitive or motor behavior, and a reorganized cortical network evidenced by the widespread, chronic alterations in cortical FC.


Asunto(s)
Conmoción Encefálica , Ratones , Animales , Conmoción Encefálica/diagnóstico por imagen , Calcio , Corteza Cerebral/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
3.
Cereb Cortex ; 32(12): 2668-2687, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34689209

RESUMEN

Motor behavior results in complex exchanges of motor and sensory information across cortical regions. Therefore, fully understanding the cerebral cortex's role in motor behavior requires a mesoscopic-level description of the cortical regions engaged, their functional interactions, and how these functional interactions change with behavioral state. Mesoscopic Ca2+ imaging through transparent polymer skulls in mice reveals elevated activation of the dorsal cerebral cortex during locomotion. Using the correlations between the time series of Ca2+ fluorescence from 28 regions (nodes) obtained using spatial independent component analysis (sICA), we examined the changes in functional connectivity of the cortex from rest to locomotion with a goal of understanding the changes to the cortical functional state that facilitate locomotion. Both the transitions from rest to locomotion and from locomotion to rest show marked increases in correlation among most nodes. However, once a steady state of continued locomotion is reached, many nodes, including primary motor and somatosensory nodes, show decreases in correlations, while retrosplenial and the most anterior nodes of the secondary motor cortex show increases. These results highlight the changes in functional connectivity in the cerebral cortex, representing a series of changes in the cortical state from rest to locomotion and on return to rest.


Asunto(s)
Calcio , Corteza Motora , Animales , Mapeo Encefálico , Diagnóstico por Imagen , Locomoción , Imagen por Resonancia Magnética , Ratones , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología
4.
Mycoses ; 62(9): 739-745, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31044442

RESUMEN

Mediastinal mucormycosis is an uncommon but lethal infection associated with an 83% mortality. We describe a case of fatal Rhizopus microsporus mediastinitis despite three exploratory mediastinal surgeries and complementary systemic and mediastinal irrigation with liposomal amphotericin B. We further review the literature on surgical and antifungal management of mediastinal mucormycosis.


Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Enfermedades del Mediastino/diagnóstico , Enfermedades del Mediastino/microbiología , Mucormicosis/diagnóstico , Mucormicosis/tratamiento farmacológico , Adulto , Resultado Fatal , Femenino , Humanos , Enfermedades del Mediastino/tratamiento farmacológico , Enfermedades del Mediastino/cirugía , Rhizopus/efectos de los fármacos , Irrigación Terapéutica
5.
Neurobiol Dis ; 112: 35-48, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29331264

RESUMEN

Myotonic dystrophy (DM) is a progressive, multisystem disorder affecting skeletal muscle, heart, and central nervous system. In both DM1 and DM2, microsatellite expansions of CUG and CCUG RNA repeats, respectively, accumulate and disrupt functions of alternative splicing factors, including muscleblind (MBNL) proteins. Grey matter loss and white matter changes, including the corpus callosum, likely underlie cognitive and executive function deficits in DM patients. However, little is known how cerebral cortical circuitry changes in DM. Here, flavoprotein optical imaging was used to assess local and contralateral responses to intracortical motor cortex stimulation in DM-related mouse models. In control mice, brief train stimulation generated ipsilateral and contralateral homotopic fluorescence increases, the latter mediated by the corpus callosum. Single pulse stimulation produced an excitatory response with an inhibitory-like surround response mediated by GABAA receptors. In a mouse model of DM2 (Mbnl2 KO), we observed prolonged and increased responsiveness to train stimulation and loss of the inhibition from single pulse stimulation. Conversely, mice overexpressing human MBNL1 (MBNL1-OE) exhibited decreased contralateral response to train stimulation and reduction of inhibitory-like surround to single pulse stimulation. Therefore, altering levels of two key DM-associated splicing factors modifies functions of local cortical circuits and contralateral responses mediated through the corpus callosum.


Asunto(s)
Empalme Alternativo/fisiología , Modelos Animales de Enfermedad , Corteza Motora/metabolismo , Distrofia Miotónica/metabolismo , Proteínas de Unión al ARN/biosíntesis , Animales , Estimulación Eléctrica/métodos , Potenciales Postsinápticos Excitadores/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Corteza Motora/fisiopatología , Distrofia Miotónica/genética , Distrofia Miotónica/fisiopatología , Empalme del ARN/fisiología , Proteínas de Unión al ARN/genética
6.
J Neurosci ; 35(14): 5664-79, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25855180

RESUMEN

The Ca(2+) channelopathies caused by mutations of the CACNA1A gene that encodes the pore-forming subunit of the human Cav2.1 (P/Q-type) voltage-gated Ca(2+) channel include episodic ataxia type 2 (EA2). Although, in EA2 the emphasis has been on cerebellar dysfunction, patients also exhibit episodic, nonmotoric abnormalities involving the cerebral cortex. This study demonstrates episodic, low-frequency oscillations (LFOs) throughout the cerebral cortex of tottering (tg/tg) mice, a widely used model of EA2. Ranging between 0.035 and 0.11 Hz, the LFOs in tg/tg mice can spontaneously develop very high power, referred to as a high-power state. The LFOs in tg/tg mice are mediated in part by neuronal activity as tetrodotoxin decreases the oscillations and cortical neuron discharge contain the same low frequencies. The high-power state involves compensatory mechanisms because acutely decreasing P/Q-type Ca(2+) channel function in either wild-type (WT) or tg/tg mice does not induce the high-power state. In contrast, blocking l-type Ca(2+) channels, known to be upregulated in tg/tg mice, reduces the high-power state. Intriguingly, basal excitatory glutamatergic neurotransmission constrains the high-power state because blocking ionotropic or metabotropic glutamate receptors results in high-power LFOs in tg/tg but not WT mice. The high-power LFOs are decreased markedly by acetazolamide and 4-aminopyridine, the primary treatments for EA2, suggesting disease relevance. Together, these results demonstrate that the high-power LFOs in the tg/tg cerebral cortex represent a highly abnormal excitability state that may underlie noncerebellar symptoms that characterize CACNA1A mutations.


Asunto(s)
Canales de Calcio Tipo N/genética , Corteza Cerebral/fisiopatología , Canalopatías/genética , Canalopatías/patología , Sincronización Cortical/genética , Mutación/genética , 4-Aminopiridina/farmacología , Acetazolamida/farmacología , Animales , Bencenoacetamidas , Corteza Cerebral/patología , Sincronización Cortical/efectos de los fármacos , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Femenino , Masculino , Ratones , Ratones Transgénicos , NG-Nitroarginina Metil Éster/farmacología , Neurotransmisores/farmacología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Bloqueadores de los Canales de Potasio/farmacología , Piridinas , Quinoxalinas/farmacología , Vibrisas/inervación
7.
J Interv Cardiol ; 28(3): 223-32, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25991082

RESUMEN

OBJECTIVE: We sought to examine the relationship between preoperative platelet function and perioperative bleeding in patients undergoing CABG. BACKGROUND: There are many ways to measure platelet aggregability. Little is known about their correlations with one another, or with bleeding. METHODS: We prospectively studied 50 patients undergoing a first isolated off-pump CABG. Thirty-four were exposed to a thienopyridine prior to surgery; 16 were not. Preoperative platelet function was measured by VerifyNow®, TEG®, AggreGuide™, Plateletworks®, vasodilator-stimulated phosphoprotein (VASP) phosphorylation, and light transmission aggregometry. Bleeding was assessed 2 ways: drop from pre- to nadir postoperative hematocrit, and chest tube drainage. Correlation coefficients were calculated using Spearman's rank-order correlation. RESULTS: Mean age was 62 years. Patient characteristics and surgical details were similar between the thienopyridine-exposed and non-exposed patients. The correlation coefficients between the 4 point-of-care platelet function measurements and hematocrit change ranged from -0.2274 to 0.2882. Only Plateletworks® correlated with drop in hematocrit (r = 0.2882, P = 0.0470). The correlation coefficients between each of the 4 point-of-care platelet function tests and the chest tube drainage were also poor, ranging from -0.3073 to 0.2272. Both AggreGuide™ (r = -0.3073, P = 0.0317) and VASP (r = -0.3187, P = 0.0272) were weakly but significantly correlated with chest tube drainage. The correlation among the 4 point-of-care platelet function measurements was poor, with coefficients ranging from -0.2504 to 0.1968. CONCLUSIONS: We observed little correlation among 4 platelet function tests, and between those assays and perioperative bleeding defined 2 different ways. Whether any of these assays should be used to guide decision making in individual patients is unclear.


Asunto(s)
Pruebas de Coagulación Sanguínea , Pérdida de Sangre Quirúrgica , Puente de Arteria Coronaria Off-Pump , Agregación Plaquetaria , Anciano , Tubos Torácicos , Drenaje , Femenino , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Sistemas de Atención de Punto , Periodo Preoperatorio , Estudios Prospectivos
8.
Health Promot Int ; 30(3): 793-802, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24052334

RESUMEN

Olympic Games have sometimes been considered as public health interventions capable of improving population health by encouraging increased physical activity levels. However, the evidence base does not appear to support this and is of poor quality, focussing on population level outcomes, usually related only to participation in organised sports. A new approach to research into the effects of such events is required focussing on the processes and mechanisms by which population physical activity levels might be increased enabling more effective use of such events in the future. Two separate processes, the 'demonstration effect' and 'festival effect,' have been proposed in Government guidance and are explored using qualitative methods in eight inactive people and four physical activity promotion specialists in Brighton & Hove. The findings appear to support the idea that watching elite athletes compete is unlikely to inspire participation among inactive people and may even discourage it by reducing self-efficacy as a result of the perceived competence gap. Despite this, positive attitudes towards the London Olympics were observed among inactive members of the public and a desire to become actively involved in the event. Examples of intention to continue participating in community events and physical activities as a result of positive experiences of Olympic related events were also observed.


Asunto(s)
Actitud , Ejercicio Físico/psicología , Motivación , Deportes/psicología , Adulto , Femenino , Humanos , Entrevistas como Asunto , Londres , Masculino , Persona de Mediana Edad , Investigación Cualitativa
9.
bioRxiv ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38948725

RESUMEN

Spinocerebellar Ataxia Type 8 (SCA8) is an inherited neurodegenerative disease caused by a bidirectionally expressed CTG●CAG expansion mutation in the ATXN-8 and ATXN8-OS genes. While primarily a motor disorder, psychiatric and cognitive symptoms have been reported. It is difficult to elucidate how the disease alters brain function in areas with little or no degeneration producing both motor and cognitive symptoms. Using transparent polymer skulls and CNS-wide GCaMP6f expression, we studied neocortical networks throughout SCA8 progression using wide-field Ca2+ imaging in a transgenic mouse model of SCA8. We observed that neocortical networks in SCA8+ mice were hyperconnected globally which led to network configurations with increased global efficiency and centrality. At the regional level, significant network changes occurred in nearly all cortical regions, however mainly involved sensory and association cortices. Changes in functional connectivity in anterior motor regions worsened later in the disease. Near perfect decoding of animal genotype was obtained using a generalized linear model based on canonical correlation strengths between activity in cortical regions. The major contributors to decoding were concentrated in the somatosensory, higher visual and retrosplenial cortices and occasionally extended into the motor regions, demonstrating that the areas with the largest network changes are predictive of disease state.

10.
J Neurochem ; 125(5): 673-84, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23495967

RESUMEN

Spreading depolarization (SD) is a feed-forward wave that propagates slowly throughout brain tissue and recovery from SD involves substantial metabolic demand. Presynaptic Zn(2+) release and intracellular accumulation occurs with SD, and elevated intracellular Zn(2+) ([Zn(2+) ]i ) can impair cellular metabolism through multiple pathways. We tested here whether increased [Zn(2+) ]i could exacerbate the metabolic challenge of SD, induced by KCl, and delay recovery in acute murine hippocampal slices. [Zn(2+) ]i loading prior to SD, by transient ZnCl2 application with the Zn(2+) ionophore pyrithione (Zn/Pyr), delayed recovery of field excitatory post-synaptic potentials (fEPSPs) in a concentration-dependent manner, prolonged DC shifts, and significantly increased extracellular adenosine accumulation. These effects could be due to metabolic inhibition, occurring downstream of pyruvate utilization. Prolonged [Zn(2+) ]i accumulation prior to SD was required for effects on fEPSP recovery and consistent with this, endogenous synaptic Zn(2+) release during SD propagation did not delay recovery from SD. The effects of exogenous [Zn(2+) ]i loading were also lost in slices preconditioned with repetitive SDs, implying a rapid adaptation. Together, these results suggest that [Zn(2+) ]i loading prior to SD can provide significant additional challenge to brain tissue, and could contribute to deleterious effects of [Zn(2+) ]i accumulation in a range of brain injury models.


Asunto(s)
Cloruros/metabolismo , Depresión de Propagación Cortical/fisiología , Líquido Intracelular/metabolismo , Sinapsis/metabolismo , Regulación hacia Arriba/fisiología , Compuestos de Zinc/metabolismo , Animales , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
11.
Dystonia ; 22023.
Artículo en Inglés | MEDLINE | ID: mdl-37800168

RESUMEN

Episodic Ataxia Type 2 (EA2) is a rare neurological disorder caused by a mutation in the CACNA1A gene, encoding the P/Q-type voltage-gated Ca2+ channel important for neurotransmitter release. Patients with this channelopathy exhibit both cerebellar and cerebral pathologies, suggesting the condition affects both regions. The tottering (tg/tg) mouse is the most commonly used EA2 model due to an orthologous mutation in the cacna1a gene. The tg/tg mouse has three prominent behavioral phenotypes: a dramatic episodic dystonia; absence seizures with generalized spike and wave discharges (GSWDs); and mild ataxia. We previously observed a novel brain state, transient low-frequency oscillations (LFOs) in the cerebellum and cerebral cortex under anesthesia. In this study, we examine the relationships among the dystonic attack, GSWDs, and LFOs in the cerebral cortex. Previous studies characterized LFOs in the motor cortex of anesthetized tg/tg mice using flavoprotein autofluorescence imaging testing the hypothesis that LFOs provide a mechanism for the paroxysmal dystonia. We sought to obtain a more direct understanding of motor cortex (M1) activity during the dystonic episodes. Using two-photon Ca2+ imaging to investigate neuronal activity in M1 before, during, and after the dystonic attack, we show that there is not a significant change in the activity of M1 neurons from baseline through the attack. We also conducted simultaneous, multi-electrode recordings to further understand how M1 cellular activity and local field potentials change throughout the progression of the dystonic attack. Neither putative pyramidal nor inhibitory interneuron firing rate changed during the dystonic attack. However, we did observe a near complete loss of GSWDs during the dystonic attack in M1. Finally, using spike triggered averaging to align simultaneously recorded limb kinematics to the peak Ca2+ response, and vice versa, revealed a reduction in the spike triggered average during the dystonic episodes. Both the loss of GSWDs and the reduction in the coupling suggest that, during the dystonic attack, M1 is effectively decoupled from other structures. Overall, these results indicate that the attack is not initiated or controlled in M1, but elsewhere in the motor circuitry. The findings also highlight that LFOs, GSWDs, and dystonic attacks represent three brain states in tg/tg mice.

12.
bioRxiv ; 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37333228

RESUMEN

Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.

13.
Res Sq ; 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38014260

RESUMEN

Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.

14.
Biology (Basel) ; 11(11)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358302

RESUMEN

A central tenet of neuroscience is that sensory, motor, and cognitive behaviors are generated by the communications and interactions among neurons, distributed within and across anatomically and functionally distinct brain regions. Therefore, to decipher how the brain plans, learns, and executes behaviors requires characterizing neuronal activity at multiple spatial and temporal scales. This includes simultaneously recording neuronal dynamics at the mesoscale level to understand the interactions among brain regions during different behavioral and brain states. Wide-field Ca2+ imaging, which uses single photon excitation and improved genetically encoded Ca2+ indicators, allows for simultaneous recordings of large brain areas and is proving to be a powerful tool to study neuronal activity at the mesoscopic scale in behaving animals. This review details the techniques used for wide-field Ca2+ imaging and the various approaches employed for the analyses of the rich neuronal-behavioral data sets obtained. Also discussed is how wide-field Ca2+ imaging is providing novel insights into both normal and altered neural processing in disease. Finally, we examine the limitations of the approach and new developments in wide-field Ca2+ imaging that are bringing new capabilities to this important technique for investigating large-scale neuronal dynamics.

15.
Curr Biol ; 32(1): 14-25.e4, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-34678162

RESUMEN

Schizophrenia results from hundreds of known causes, including genetic, environmental, and developmental insults that cooperatively increase risk of developing the disease. In spite of the diversity of causal factors, schizophrenia presents with a core set of symptoms and brain abnormalities (both structural and functional) that particularly impact the prefrontal cortex. This suggests that many different causal factors leading to schizophrenia may cause prefrontal neurons and circuits to fail in fundamentally similar ways. The nature of convergent malfunctions in prefrontal circuits at the cell and synaptic levels leading to schizophrenia are not known. Here, we apply convergence-guided search to identify core pathological changes in the functional properties of prefrontal circuits that lie downstream of mechanistically distinct insults relevant to the disease. We compare the impacts of blocking NMDA receptors in monkeys and deleting a schizophrenia risk gene in mice on activity timing and effective communication in prefrontal local circuits. Although these manipulations operate through distinct molecular pathways and biological mechanisms, we found they produced convergent pathophysiological effects on prefrontal local circuits. Both manipulations reduced the frequency of synchronous (0-lag) spiking between prefrontal neurons and weakened functional interactions between prefrontal neurons at monosynaptic lags as measured by information transfer between the neurons. The two observations may be related, as reduction in synchronous spiking between prefrontal neurons would be expected to weaken synaptic connections between them via spike-timing-dependent synaptic plasticity. These data suggest that the link between spike timing and synaptic connectivity could comprise the functional vulnerability that multiple risk factors exploit to produce disease.


Asunto(s)
Esquizofrenia , Animales , Ratones , Neuronas/metabolismo , Corteza Prefrontal/fisiología , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/genética
16.
Adv Healthc Mater ; 11(18): e2200626, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35869830

RESUMEN

Electrophysiology and optical imaging provide complementary neural sensing capabilities - electrophysiological recordings have high temporal resolution, while optical imaging allows recording of genetically-defined populations at high spatial resolution. Combining these two modalities for simultaneous large-scale, multimodal sensing of neural activity across multiple brain regions can be very powerful. Here, transparent, inkjet-printed electrode arrays with outstanding optical and electrical properties are seamlessly integrated with morphologically conformant transparent polymer skulls. Implanted on transgenic mice expressing the Calcium (Ca2+ ) indicator GCaMP6f in excitatory neurons, these "eSee-Shells" provide a robust opto-electrophysiological interface for over 100 days. eSee-Shells enable simultaneous mesoscale Ca2+ imaging and electrocorticography (ECoG) acquisition from multiple brain regions covering 45 mm2 of cortex under anesthesia and in awake animals. The clarity and transparency of eSee-Shells allow recording single-cell Ca2+ signals directly below the electrodes and interconnects. Simultaneous multimodal measurement of cortical dynamics reveals changes in both ECoG and Ca2+ signals that depend on the behavioral state.


Asunto(s)
Calcio , Polímeros , Animales , Electrodos Implantados , Fenómenos Electrofisiológicos , Ratones , Ratones Transgénicos , Cráneo
17.
J Neurosci Methods ; 354: 109100, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33600850

RESUMEN

Deciphering neurologic function is a daunting task, requiring understanding the neuronal networks and emergent properties that arise from the interactions among single neurons. Mechanistic insights into neuronal networks require tools that simultaneously assess both single neuron activity and the consequent mesoscale output. The development of cranial window technologies, in which the skull is thinned or replaced with a synthetic optical interface, has enabled monitoring neuronal activity from subcellular to mesoscale resolution in awake, behaving animals when coupled with advanced microscopy techniques. Here we review recent achievements in cranial window technologies, appraise the relative merits of each design and discuss the future research in cranial window design.


Asunto(s)
Encéfalo , Cráneo , Animales , Microscopía , Neuronas , Tecnología
18.
Physiother Theory Pract ; 36(6): 761-767, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29952692

RESUMEN

Sacroiliac joint (SIJ) pain has been identified as a primary or contributing source of pain in patients with low back pain. The Laslett cluster of SIJ pain provocation tests has the strongest evidence for noninvasive clinical testing. The purpose of this report was to describe the impact of physical therapy treatments for a patient postpartum with SIJ pain who satisfied the Laslett cluster. Specifically, the goal was to assess the impact of progressive pelvic floor muscle exercise and manual therapy. The Modified Oswestry Low Back Pain Disability Questionnaire (MODI) was the primary outcome measure used in this case. In addition, the Numeric Pain Rating Scale (NRPS) and Global Rating of Change (GROC) were used as secondary outcome measures. In this case report, the patient responded to the combined interventions with decreases in MODI, NRPS and GROC. Further research is warranted to develop stronger evidence to identify specific interventions for the treatment of SIJ pain.


Asunto(s)
Artralgia/rehabilitación , Diafragma Pélvico/fisiopatología , Modalidades de Fisioterapia , Articulación Sacroiliaca/fisiopatología , Evaluación de la Discapacidad , Femenino , Humanos , Persona de Mediana Edad , Dimensión del Dolor , Periodo Posparto
19.
World Neurosurg ; 138: 360-362, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32200012

RESUMEN

BACKGROUND: Retained old cerebrospinal fluid diversion shunt catheters in the neck, chest, or abdominal walls are frequently encountered in patients with lifelong shunt-dependent hydrocephalus who have undergone multiple shunt revisions. Particularly in cases where years and decades go between shunt revisions, the distal catheter portion can get calcified and nearly impossible to remove. Most patients tolerate a retained shunt catheter without problems. In some patients, however, retained catheters can cause pain and discomfort, particularly over the clavicle with head movements. Albeit trivial, we are unaware of innovative solutions to this problem. Here, we describe the use of an endoscopic vein harvest device used in cardiothoracic surgery to completely remove an old, calcified shunt catheter. METHODS: Removal of a calcified ventriculoperitoneal shunt catheter using an endoscopic vein harvesting system was performed in a 32-year-old man with shunt-dependent hydrocephalus from premature birth. At 14 years of age, the patient had his only shunt revision consisting of a new distal catheter being placed adjacent to the old catheter. The patient presented with significant discomfort from the retained original shunt catheter. RESULTS: Using the endoscopic vein harvesting system, the shunt catheter was removed minimally invasively and the patient had complete resolution of his symptomatology. CONCLUSIONS: The endoscopic vein harvesting system used in cardiothoracic surgery is a suitable instrument to remove long segments of a retained ventriculoperitoneal shunt catheter minimally invasively through a small skin incision. To our knowledge, this is the first report of minimally invasive removal of a retained ventriculoperitoneal catheter.


Asunto(s)
Catéteres de Permanencia/efectos adversos , Remoción de Dispositivos/instrumentación , Remoción de Dispositivos/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Derivación Ventriculoperitoneal/efectos adversos , Adulto , Humanos , Masculino
20.
Am J Cardiol ; 125(7): 1088-1095, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32046822

RESUMEN

There is growing interest in "minimalist" transcatheter aortic valve implantation (M-TAVI), performed with conscious sedation instead of general anesthesia (GA-TAVI). We assessed the impact of M-TAVI on procedural efficiency, long-term safety, and quality of life (QoL) in 477 patients with severe aortic stenosis (82 years, women 50%, STS 5.0), who underwent M-TAVI (n = 278) or GA-TAVI (n = 199). M-TAVI patients were less likely to have NYHA Class ≥3, valve-in-valve TAVI, and receive self-expanding valves. M-TAVI was completed without conversion to GA in 269 (97%) patients. M-TAVI was more efficient that GA-TAVI including shorter lengths of stay (2 vs 3 days, p <0.0001), higher likelihood of being discharged home (87% vs 72%, p <0.0001), less use of blood transfusions (10% vs 22%, p = 0.0008), inotropes (13% vs 32%, p <0.0001), contrast volume (50 vs 90 ml, p <0.0001), fluoroscopy time (20 vs 24 minute, p <0.0001), and need for >1 valves (0.4 vs 5.5%, p = 0.0004). At 1-month, death/stroke (M-TAVI vs GA-TAVI 4.0 vs 6.5%) and a "safety composite" end point (death, stroke, transient ischemic attack, myocardial infarction, new dialysis, major vascular complication, major or life-threatening bleeding, and new pacemaker: 17.6% vs 21.1%) were similar (p = NS for both). At a median follow-up of 365 days, survival curves showed similar incidence of death/stroke as well as the safety composite end point between the groups. QoL scores were similar at baseline and 1-month after TAVI. In multivariable analyses, M-TAVI showed significant improvements in all parameters of procedural efficiency. In conclusion, M-TAVI is more efficient than GA-TAVI, with similar safety at 1-month and long-term, and similar QoL scores at 1 month.


Asunto(s)
Anestesia General/métodos , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Sedación Consciente/métodos , Complicaciones Posoperatorias/epidemiología , Calidad de Vida , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/psicología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
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