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1.
Exp Neurol ; 374: 114695, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38246304

RESUMEN

Mild traumatic brain injury (mTBI) is a leading cause of disability in the United States, with neuropsychiatric disturbances such as depression, anxiety, PTSD, and social disturbances being common comorbidities following injury. The molecular mechanisms driving neuropsychiatric complications following neurotrauma are not well understood and current FDA-approved pharmacotherapies employed to ameliorate these comorbidities lack desired efficacy. Concerted efforts to understand the molecular mechanisms of and identify novel drug candidates for treating neurotrauma-elicited neuropsychiatric sequelae are clearly needed. Serotonin (5-HT) is linked to the etiology of neuropsychiatric disorders, however our understanding of how various forms of TBI directly affect 5-HT neurotransmission is limited. 5-HT neurons originate in the raphe nucleus (RN) of the midbrain and project throughout the brain to regulate diverse behavioral phenotypes. We hypothesize that the characterization of the dynamics governing 5-HT neurotransmission after injury will drive the discovery of novel drug targets and lead to a greater understanding of the mechanisms associated with neuropsychiatric disturbances following mild TBI (mTBI). Herein, we provide evidence that closed-head mTBI alters total DRN 5-HT levels, with RNA sequencing of the DRN revealing injury-derived alterations in transcripts required for the development, identity, and functional stability of 5-HT neurons. Further, using gene ontology analyses combined with immunohistological analyses, we have identified a novel mechanism of transcriptomic control within 5-HT neurons that may directly influence 5-HT neuron identity/function post-injury. These studies provide molecular evidence of injury-elicited 5-HT neuron dysregulation, data which may expedite the identification of novel therapeutic targets to attenuate TBI-elicited neuropsychiatric sequelae.


Asunto(s)
Conmoción Encefálica , Núcleo Dorsal del Rafe , Humanos , Serotonina , Conmoción Encefálica/complicaciones , Neuronas , Perfilación de la Expresión Génica , Neuronas Serotoninérgicas
2.
Brain Sci ; 14(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38248266

RESUMEN

Traumatic brain injury (TBI) is a pervasive public health crisis that severely impacts the quality of life of affected individuals. Like peripheral forms of trauma, TBI results from extraordinarily heterogeneous environmental forces being imparted on the cranial space, resulting in heterogeneous disease pathologies. This has made therapies for TBI notoriously difficult to develop, and currently, there are no FDA-approved pharmacotherapies specifically for the acute or chronic treatment of TBI. TBI is associated with changes in cognition and can precipitate the onset of debilitating psychiatric disorders like major depressive disorder (MDD), generalized anxiety disorder (GAD), and post-traumatic stress disorder (PTSD). Complicating these effects of TBI, FDA-approved pharmacotherapies utilized to treat these disorders often fail to reach the desired level of efficacy in the context of neurotrauma. Although a complicated association, decades of work have linked central serotonin (5-HT) neurotransmission as being involved in the etiology of a myriad of neuropsychiatric disorders, including MDD and GAD. 5-HT is a biogenic monoamine neurotransmitter that is highly conserved across scales of biology. Though the majority of 5-HT is isolated to peripheral sites such as the gastrointestinal (GI) tract, 5-HT neurotransmission within the CNS exerts exquisite control over diverse biological functions, including sleep, appetite and respiration, while simultaneously establishing normal mood, perception, and attention. Although several key studies have begun to elucidate how various forms of neurotrauma impact central 5-HT neurotransmission, a full determination of precisely how TBI disrupts the highly regulated dynamics of 5-HT neuron function and/or 5-HT neurotransmission has yet to be conceptually or experimentally resolved. The purpose of the current review is, therefore, to integrate the disparate bodies of 5-HT and TBI research and synthesize insight into how new combinatorial research regarding 5-HT neurotransmission and TBI may offer an informed perspective into the nature of TBI-induced neuropsychiatric complications.

3.
J Vis Exp ; (196)2023 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-37458423

RESUMEN

Mitochondria play many essential roles in the cell, including energy production, regulation of Ca2+ homeostasis, lipid biosynthesis, and production of reactive oxygen species (ROS). These mitochondria-mediated processes take on specialized roles in neurons, coordinating aerobic metabolism to meet the high energy demands of these cells, modulating Ca2+ signaling, providing lipids for axon growth and regeneration, and tuning ROS production for neuronal development and function. Mitochondrial dysfunction is therefore a central driver in neurodegenerative diseases. Mitochondrial structure and function are inextricably linked. The morphologically complex inner membrane with structural infolds called cristae harbors many molecular systems that perform the signature processes of the mitochondrion. The architectural features of the inner membrane are ultrastructural and therefore, too small to be visualized by traditional diffraction-limited resolved microscopy. Thus, most insights on mitochondrial ultrastructure have come from electron microscopy on fixed samples. However, emerging technologies in super-resolution fluorescence microscopy now provide resolution down to tens of nanometers, allowing visualization of ultrastructural features in live cells. Super-resolution imaging therefore offers an unprecedented ability to directly image fine details of mitochondrial structure, nanoscale protein distributions, and cristae dynamics, providing fundamental new insights that link mitochondria to human health and disease. This protocol presents the use of stimulated emission depletion (STED) super-resolution microscopy to visualize the mitochondrial ultrastructure of live human neuroblastoma cells and primary rat neurons. This procedure is organized into five sections: (1) growth and differentiation of the SH-SY5Y cell line, (2) isolation, plating, and growth of primary rat hippocampal neurons, (3) procedures for staining cells for live STED imaging, (4) procedures for live cell STED experiments using a STED microscope for reference, and (5) guidance for segmentation and image processing using examples to measure and quantify morphological features of the inner membrane.


Asunto(s)
Neuroblastoma , Humanos , Ratas , Animales , Especies Reactivas de Oxígeno/metabolismo , Neuroblastoma/metabolismo , Membranas Mitocondriales/metabolismo , Microscopía Fluorescente/métodos , Neuronas
4.
Neuroscience ; 509: 20-35, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36332692

RESUMEN

Acceleration/deceleration forces are a common component of various causes of mild traumatic brain injury (mTBI) and result in strain and shear forces on brain tissue. A small quantifiable volume dubbed the compensatory reserve volume (CRV) permits energy transmission to brain tissue during acceleration/deceleration events. The CRV is principally regulated by cerebral blood flow (CBF) and CBF is primarily determined by the concentration of inspired carbon dioxide (CO2). We hypothesized that experimental hypercapnia (i.e. increased inspired concentration of CO2) may act to prevent and mitigate the actions of acceleration/deceleration-induced TBI. To determine these effects C57Bl/6 mice underwent experimental hypercapnia whereby they were exposed to medical-grade atmospheric air or 5% CO2 immediately prior to an acceleration/deceleration-induced mTBI paradigm. mTBI results in significant increases in righting reflex time (RRT), reductions in core body temperature, and reductions in general locomotor activity-three hours post injury (hpi). Experimental hypercapnia immediately preceding mTBI was found to prevent mTBI-induced increases in RRT and reductions in core body temperature and general locomotor activity. Ribonucleic acid (RNA) sequencing conducted four hpi revealed that CO2 exposure prevented mTBI-induced transcriptional alterations of several targets related to oxidative stress, immune, and inflammatory signaling. Quantitative real-time PCR analysis confirmed the prevention of mTBI-induced increases in mitogen-activated protein kinase kinase kinase 6 and metallothionein-2. These initial proof of concept studies reveal that increases in inspired CO2 mitigate the detrimental contributions of acceleration/deceleration events in mTBI and may feasibly be translated in the future to humans using a medical device seeking to prevent mTBI among high-risk groups.


Asunto(s)
Conmoción Encefálica , Ratones , Humanos , Animales , Conmoción Encefálica/prevención & control , Dióxido de Carbono , Desaceleración , Hipercapnia , Aceleración , Respiración
5.
J Int AIDS Soc ; 25(11): e26029, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36408717

RESUMEN

INTRODUCTION: Hazardous alcohol use (HAU), defined as a pattern of alcohol consumption that increases the risk of harmful consequences for the user or others, is associated with an elevated risk of human immunodeficiency virus (HIV) infection and poor health outcomes. We describe the association between people living with HIV (PLHIV) who report HAU and key HIV indicators. Gaps in current literature in estimating HAU on HIV outcomes at the regional level of Eastern and Southern Africa still exist and our analysis aims to address this issue. METHODS: We used weighted pooled data (2015-2017) from the nationally representative Population-based HIV Impact Assessments among adults who provided written consent aged 18-59 years from Eswatini, Malawi, Namibia, Tanzania, Zambia and Zimbabwe. We estimated differences in the prevalence of HIV infection and The Joint United Nations Programme on HIV and AIDS (UNAIDS) 90-90-90 indicators between PLHIV by HAU status using log-binomial regression, stratified by sex. HAU was determined using the Alcohol Use Identification Test-Consumption. RESULTS: Among the 9755 women and 4444 men who tested HIV positive, 6.6% of women and 21.8% of men engaged in HAU. Women who reported HAU were more likely to be HIV positive (adjusted prevalence ratio [aPR] = 1.31, 95% CI: 1.18-1.46) compared to those who did not report HAU. For the UNAIDS 90-90-90 targets, women who engaged in HAU were more likely to be unaware of their HIV-positive status (aPR = 1.22, 95% CI: 1.01-1.47) and not on antiretroviral therapy (ART) (aPR = 1.73, 95% CI: 1.26-2.37). Men who engaged in HAU were more likely to be unaware of their HIV-positive status (aPR = 1.56, 95% CI 1.39-1.76) and not on ART (aPR = 1.72, 95% CI: 1.30-2.29). No difference in viral load suppression, defined as <1000 copies/ml of HIV RNA, was seen by sex. CONCLUSIONS: PLHIV who engage in HAU were more likely to have suboptimal outcomes along the HIV care continuum when compared to those who did not engage in HAU. Targeted interventions, such as alcohol screening for HAU in HIV testing and treatment settings and HIV prevention efforts in alcohol-based venues, may help countries reach HIV epidemic control by 2030.


Asunto(s)
Epidemias , Infecciones por VIH , Seropositividad para VIH , Adulto , Masculino , Femenino , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Prueba de VIH , Carga Viral , Epidemias/prevención & control , Seropositividad para VIH/complicaciones , Zimbabwe/epidemiología
6.
Biomed Phys Eng Express ; 8(6)2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36252558

RESUMEN

With the evolution of modern warfare and the increased use of improvised explosive devices (IEDs), there has been an increase in blast-induced traumatic brain injuries (bTBI) among military personnel and civilians. The increased prevalence of bTBI necessitates bTBI models that result in a properly scaled injury for the model organism being used. The primary laboratory model for bTBI is the shock tube, wherein a compressed gas ruptures a thin membrane, generating a shockwave. To generate a shock wave that is properly scaled from human to rodent subjects many pre-clinical models strive for a short duration and high peak overpressure while fitting a Friedlander waveform, the ideal representation of a blast wave. A large variety of factors have been experimentally characterized in attempts to create an ideal waveform, however we found current research on the gas composition being used to drive shock wave formation to be lacking. To better understand the effect the driver gas has on the waveform being produced, we utilized a previously established murine shock tube bTBI model in conjunction with several distinct driver gasses. In agreement with previous findings, helium produced a shock wave most closely fitting the Friedlander waveform in contrast to the plateau-like waveforms produced by some other gases. The peak static pressure at the exit of the shock tube and total pressure 5 cm from the exit have a strong negative correlation with the density of the gas being used: helium the least dense gas used produces the highest peak overpressure. Density of the driver gas also exerts a strong positive effect on the duration of the shock wave, with helium producing the shortest duration wave. Due to its ability to produce a Friedlander waveform and produce a waveform following proper injury scaling guidelines, helium is an ideal gas for use in shock tube models for bTBI.


Asunto(s)
Traumatismos por Explosión , Lesiones Encefálicas , Ratones , Humanos , Animales , Helio , Modelos Animales de Enfermedad , Explosiones
7.
Neuroreport ; 33(14): 612-616, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36062511

RESUMEN

The monoamine neurotransmitter serotonin (5-HT) is important for the regulation of behavior, and aberrations in 5-HT signaling are linked to several neuropsychiatric and neurodevelopmental disorders. 5-HT signaling is dependent on and tightly regulated by the functional activity of the 5-HT transporter (SERT). Neurotrauma is known to structurally and functionally impact 5-HT neuronal tracts and 5-HT signaling; however, the extent to which various forms of neurotrauma alter homeostatic 5-HT signaling through the modulation of SERT expression and/or functional uptake capacity is currently not well characterized. We aimed to better characterize the protein expression and uptake activity of SERT following mild traumatic brain injury (mTBI). A murine model of blast-induced mTBI was utilized to characterize alterations in SERT expression and function following injury. mTBI was found to decrease (≈26%) the protein levels of SERT 3 days postinjury (DPI) in the dorsal raphe nucleus (DRN), the primary locale of 5-HT neuronal cell bodies within the central nervous system. Concomitant reductions in midbrain SERT-dependent radiolabeled 5-HT uptake were observed 3 DPI (≈24%). No alterations in SERT expression were observed 10 DPI in the DRN. Additionally, no alterations in SERT expression or function were observed in prefrontal cortex samples at any time point observed. This data reveals time- and location-dependent alterations in SERT expression and function following mTBI. These studies illustrate the critical importance of ongoing research efforts to characterize the molecular effects of various forms of neurotrauma on SERT protein expression and function, which may yield novel drug targets within 5-HT systems.


Asunto(s)
Conmoción Encefálica , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Animales , Núcleo Dorsal del Rafe , Ratones , Neuronas/metabolismo , Serotonina/metabolismo , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo
8.
Front Pharmacol ; 13: 930346, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35910378

RESUMEN

Various forms of traumatic brain injury (TBI) are a leading cause of disability in the United States, with the generation of neuropsychiatric complications such as depression, anxiety, social dysfunction, and suicidality being common comorbidities. Serotonin (5-HT) signaling is linked to psychiatric disorders; however, the effects of neurotrauma on normal, homeostatic 5-HT signaling within the central nervous system (CNS) have not been well characterized. We hypothesize that TBI alters specific components of 5-HT signaling within the CNS and that the elucidation of specific TBI-induced alterations in 5-HT signaling may identify novel targets for pharmacotherapies that ameliorate the neuropsychiatric complications of TBI. Herein, we provide evidence that closed-head blast-induced mild TBI (mTBI) results in selective alterations in cortical 5-HT2A receptor signaling. We find that mTBI increases in vivo cortical 5-HT2A receptor sensitivity and ex vivo radioligand binding at time points corresponding with mTBI-induced deficits in social behavior. In contrast, in vivo characterizations of 5-HT1A receptor function revealed no effect of mTBI. Notably, we find that repeated pharmacologic activation of 5-HT2A receptors post-injury reverses deficits in social dominance resulting from mTBI. Cumulatively, these studies provide evidence that mTBI drives alterations in cortical 5-HT2A receptor function and that selective targeting of TBI-elicited alterations in 5-HT2A receptor signaling may represent a promising avenue for the development of pharmacotherapies for TBI-induced generation of neuropsychiatric disorders.

9.
Popul Health Manag ; 25(1): 31-38, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34161148

RESUMEN

Approximately 1 in 3 American adults has prediabetes, a condition characterized by blood glucose levels that are above normal, not in the type 2 diabetes ranges, and that increases the risk of developing type 2 diabetes. Evidence-based treatments can be used to prevent or delay type 2 diabetes in adults with prediabetes. The American Medical Association (AMA) has collaborated with health care organizations across the country to build sustainable diabetes prevention strategies. In 2017, the AMA formed the Diabetes Prevention Best Practices Workgroup (DPBP) with representatives from 6 health care organizations actively implementing diabetes prevention. Each organization had a unique strategy, but all included the National Diabetes Prevention Program lifestyle change program as a core evidence-based intervention. DPBP established the goal of disseminating best practices to guide other health care organizations in implementing diabetes prevention and identifying and managing patients with prediabetes. Workgroup members recognized similarities in some of their basic steps and considerations and synthesized their practices to develop best practice recommendations for 3 strategy maturity phases. Recommendations for each maturity phase are classified into 6 categories: (1) organizational support; (2) workforce and funding; (3) promotion and dissemination; (4) clinical integration and support; (5) evaluation and outcomes; (6) and program. As the burden of chronic disease grows, prevention must be prioritized and integrated into health care. These maturity phases and best practice recommendations can be used by any health care organization committed to diabetes prevention. Further research is suggested to assess the impact and adoption of diabetes prevention best practices.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estado Prediabético , Adulto , Atención a la Salud , Diabetes Mellitus Tipo 2/prevención & control , Humanos , Estilo de Vida , Estado Prediabético/terapia
10.
JAMIA Open ; 4(4): ooab101, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34870108

RESUMEN

The objective of this study was to determine if certified electronic health record technology (CEHRT) can be used to identify and refer patients with prediabetes to lifestyle change programs (LCPs) recognized by the National Diabetes Prevention Program (DPP). This pilot utilized a prediabetes registry, patient portal, and clinical decision support to increase referrals. Data from 36 primary care providers showed 4930 patients were eligible for DPP LCP, 293 referrals were generated, compared to 20 referrals in the baseline period, and 116 patients enrolled. Referral to enrollment conversion rates were 41% in the study period and 69% in the post-study 1-year period. CEHRT functionalities can support systematic identification and management of prediabetes. The referral rate increased 7-fold compared to the baseline period, with high referral to enrollment conversion rates. CEHRT coupled with active provider engagement can serve as a tool to identify prediabetes patients and facilitate LCP referrals and enrollment.

11.
ACS Appl Mater Interfaces ; 10(2): 2058-2066, 2018 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-29303241

RESUMEN

Metal-assisted chemical etching (MacEtch) has been established as a low-cost, benchtop, and versatile method for large-scale fabrication of semiconductor nanostructures and has been heralded as an alternative to conventional top-down approaches such as reactive-ion etching. However, extension of this technique to ternary III-V compound semiconductor alloys and heteroepitaxial systems has remained relatively unexplored. Here, Au-assisted and inverse-progression MacEtch (I-MacEtch) of the heteroepitaxial In0.49Ga0.51P/GaAs material system is demonstrated, along with a method for fabricating suspended InGaP nanofoils of tunable thickness in solutions of hydrofluoric acid (HF) and hydrogen peroxide (H2O2). A comparison between Au- and Cr-patterned samples is used to demonstrate the catalytic role of Au in the observed etching behavior. Vertical etch rates for nominally undoped, p-type, and n-type InGaP are determined to be ∼9.7, ∼8.7, and ∼8.8 nm/min, respectively. The evolution of I-MacEtch in the InGaP/GaAs system is tracked, leading to the formation of nanocavities located at the center of off-metal windows. Upon nanocavity formation, additional localized mass-transport pathways to the underlying GaAs substrate permit its rapid dissolution. Differential etch rates between the epilayer and substrate are exploited in the fabrication of InGaP nanofoils that are suspended over micro-trenches formed in the GaAs substrate. A model is provided for the observed I-MacEtch mechanism, based on an overlap of neighboring injected hole distribution profiles. The nanofabrication methodology shown here can be applied to various heteroepitaxial III-V systems and can directly impact the conventional processing of device applications in photonics, optoelectronics, photovoltaics, and nanoelectronics.

12.
Langmuir ; 34(1): 191-197, 2018 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-29256617

RESUMEN

Autofluorescent bovine serum albumin (BSA) hydrogel microspheres were prepared through the spray-drying of glutaraldehyde cross-linked BSA nanoparticles and then used for a proteinase K based degradation study in an aqueous solution. Experimental results and empirical models are presented to characterize the kinetics of BSA hydrogel microsphere degradation, as well as the accompanying release of synthesized fluorophore. The BSA gel degradation dynamics is primarily controlled by the concentration of proteinase K within the Tris buffer. The coupling of swelling dynamics and the transient distributions of fluorophore are traced by confocal microscopy. Models are developed based on the linear theory of elastic deformation coupled to enzyme and fluorophore transport. This study represents a fundamental investigation of the degradation and release kinetics of protein-based materials, which can potentially be applied for the dynamic and photostable tracking of relevant in vivo systems.


Asunto(s)
Endopeptidasa K/metabolismo , Colorantes Fluorescentes/química , Microesferas , Proteolisis , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Animales , Bovinos , Glutaral/química , Hidrogeles/química , Modelos Moleculares , Conformación Proteica
13.
PLoS One ; 12(8): e0183106, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28806772

RESUMEN

Extreme heat events will become more frequent under anthropogenic climate change, especially in Mediterranean ecosystems. Microhabitats can considerably moderate (buffer) the effects of extreme weather events and hence facilitate the persistence of some components of the biodiversity. We investigate the microclimatic moderation provided by two important microhabitats (cavities formed by the leaves of the grass-tree Xanthorrhoea semiplana F.Muell., Xanthorrhoeaceae; and inside the leaf-litter) during the summer of 2015/16 on the Fleurieu Peninsula of South Australia. We placed microsensors inside and outside these microhabitats, as well as above the ground below the forest canopy. Grass-tree and leaf-litter microhabitats significantly buffered against high temperatures and low relative humidity, compared to ground-below-canopy sensors. There was no significant difference between grass-tree and leaf-litter temperatures: in both microhabitats, daily temperature variation was reduced, day temperatures were 1-5°C cooler, night temperatures were 0.5-3°C warmer, and maximum temperatures were up to 14.4°C lower, compared to ground-below-canopy sensors. Grass-tree and leaf-litter microhabitats moderated heat increase at an average rate of 0.24°C temperature per 1°C increase of ambient temperature in the ground-below-canopy microhabitat. The average daily variation in temperature was determined by the type (grass-tree and leaf-litter versus ground-below-canopy) of microhabitat (explaining 67%), the amount of canopy cover and the area of the vegetation fragment (together explaining almost 10% of the variation). Greater canopy cover increased the amount of microclimatic moderation provided, especially in the leaf-litter. Our study highlights the importance of microhabitats in moderating macroclimatic conditions. However, this moderating effect is currently not considered in species distribution modelling under anthropogenic climate change nor in the management of vegetation. This shortcoming will have to be addressed to obtain realistic forecasts of future species distributions and to achieve effective management of biodiversity.


Asunto(s)
Ecosistema , Microclima , Estaciones del Año , Temperatura , Geografía , Humedad , Modelos Lineales , Región Mediterránea
14.
J Cell Biol ; 212(3): 307-19, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26833787

RESUMEN

Kinetochores attach chromosomes to the spindle microtubules and signal the spindle assembly checkpoint to delay mitotic exit until all chromosomes are attached. Light microscopy approaches aimed to indirectly determine distances between various proteins within the kinetochore (termed Delta) suggest that kinetochores become stretched by spindle forces and compact elastically when the force is suppressed. Low Delta is believed to arrest mitotic progression in taxol-treated cells. However, the structural basis of Delta remains unknown. By integrating same-kinetochore light microscopy and electron microscopy, we demonstrate that the value of Delta is affected by the variability in the shape and size of outer kinetochore domains. The outer kinetochore compacts when spindle forces are maximal during metaphase. When the forces are weakened by taxol treatment, the outer kinetochore expands radially and some kinetochores completely lose microtubule attachment, a condition known to arrest mitotic progression. These observations offer an alternative interpretation of intrakinetochore tension and question whether Delta plays a direct role in the control of mitotic progression.


Asunto(s)
Cinetocoros/efectos de los fármacos , Mitosis/efectos de los fármacos , Paclitaxel/farmacología , Epitelio Pigmentado de la Retina/efectos de los fármacos , Línea Celular , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Proteínas del Citoesqueleto , Elasticidad , Cinetocoros/metabolismo , Cinetocoros/ultraestructura , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Microscopía Electrónica , Microscopía Fluorescente , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Conformación Proteica , Proteínas Recombinantes de Fusión/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/ultraestructura , Estrés Mecánico , Factores de Tiempo , Transfección
16.
Nat Cell Biol ; 17(9): 1134-44, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26258631

RESUMEN

Mitotic spindle formation relies on the stochastic capture of microtubules at kinetochores. Kinetochore architecture affects the efficiency and fidelity of this process with large kinetochores expected to accelerate assembly at the expense of accuracy, and smaller kinetochores to suppress errors at the expense of efficiency. We demonstrate that on mitotic entry, kinetochores in cultured human cells form large crescents that subsequently compact into discrete structures on opposite sides of the centromere. This compaction occurs only after the formation of end-on microtubule attachments. Live-cell microscopy reveals that centromere rotation mediated by lateral kinetochore-microtubule interactions precedes the formation of end-on attachments and kinetochore compaction. Computational analyses of kinetochore expansion-compaction in the context of lateral interactions correctly predict experimentally observed spindle assembly times with reasonable error rates. The computational model suggests that larger kinetochores reduce both errors and assembly times, which can explain the robustness of spindle assembly and the functional significance of enlarged kinetochores.


Asunto(s)
Cinetocoros/ultraestructura , Huso Acromático/metabolismo , Línea Celular , Cromosomas Humanos/metabolismo , Humanos , Cinetocoros/metabolismo , Puntos de Control de la Fase M del Ciclo Celular , Microtúbulos/metabolismo , Transporte de Proteínas
17.
Nurs Ethics ; 22(1): 32-42, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24482261

RESUMEN

BACKGROUND: Nursing practice is complex, as nurses are challenged by increasingly intricate moral and ethical judgments. Inadequately studied in underrepresented groups in nursing, moral distress is a serious problem internationally for healthcare professionals with deleterious effects to patients, nurses, and organizations. Moral distress among nurses has been shown to contribute to decreased job satisfaction and increased turnover, withdrawal from patients, physical and psychological symptoms, and intent to leave current position or to leave the profession altogether. RESEARCH QUESTION: Do significant gender differences exist in the moral distress scores of critical care nurses? RESEARCH DESIGN: This study utilized a quantitative, descriptive methodology to explore moral distress levels in a sample of critical care nurses to determine whether gender differences exist in their mean moral distress scores. PARTICIPANTS AND RESEARCH CONTEXT: Participants (n = 31) were critical care nurses from an American Internet nursing community who completed the Moral Distress Scale-Revised online over a 5-day period in July 2013. ETHICAL CONSIDERATIONS: Institutional review board review approved the study, and accessing and completing the survey implied informed consent. FINDINGS: The results revealed a statistically significant gender difference in the mean moral distress scores of participants. Females reported statistically significantly higher moral distress scores than did males. Overall, the moral distress scores for both groups were relatively low. DISCUSSION: The findings of a gender difference have not previously been reported in the literature. However, other findings are consistent with previous studies on moral distress. CONCLUSION: Although the results of this study are not generalizable, they do suggest the need for continuing research on moral distress in underrepresented groups in nursing, including cultural and ethnic groups.


Asunto(s)
Actitud del Personal de Salud , Enfermería de Cuidados Críticos , Identidad de Género , Principios Morales , Conflicto Psicológico , Ética en Enfermería , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Enfermeras y Enfermeros/psicología , Enfermeras y Enfermeros/estadística & datos numéricos , Proyectos de Investigación , Estrés Psicológico/etiología , Estrés Psicológico/psicología
18.
J Cell Biol ; 207(1): 123-37, 2014 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-25313408

RESUMEN

Airway multiciliated epithelial cells play crucial roles in the mucosal defense system, but their differentiation process remains poorly understood. Mice lacking the basal body component Chibby (Cby) exhibit impaired mucociliary transport caused by defective ciliogenesis, resulting in chronic airway infection. In this paper, using primary cultures of mouse tracheal epithelial cells, we show that Cby facilitates basal body docking to the apical cell membrane through proper formation of ciliary vesicles at the distal appendage during the early stages of ciliogenesis. Cby is recruited to the distal appendages of centrioles via physical interaction with the distal appendage protein CEP164. Cby then associates with the membrane trafficking machinery component Rabin8, a guanine nucleotide exchange factor for the small guanosine triphosphatase Rab8, to promote recruitment of Rab8 and efficient assembly of ciliary vesicles. Thus, our study identifies Cby as a key regulator of ciliary vesicle formation and basal body docking during the differentiation of airway ciliated cells.


Asunto(s)
Proteínas Portadoras/metabolismo , Cilios/metabolismo , Células Epiteliales/citología , Proteínas de Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Mucosa Respiratoria/citología , Secuencias de Aminoácidos/genética , Animales , Cuerpos Basales/fisiología , Proteínas Portadoras/genética , Diferenciación Celular , Línea Celular Tumoral , Membrana Celular/metabolismo , Centriolos/fisiología , Cilios/genética , Quinasas del Centro Germinal , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Microtúbulos/genética , Depuración Mucociliar/genética , Naftalenos , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Estructura Terciaria de Proteína , Transporte de Proteínas , Interferencia de ARN , ARN Interferente Pequeño , Proteínas de Unión al GTP rab/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-25667814

RESUMEN

OBJECTIVE: To determine if any monotherapy drug treatment has robust efficacy to treat comorbid bipolar disorder and chronic pain. DATA SOURCES: The American Psychiatric Association (APA) treatment guidelines for bipolar mood disorder and the 2012 Cochrane database for pain disorders. STUDY SELECTION: We relied on the treatment guides to determine if the drugs that are APA guideline-supported to treat bipolar disorder have supporting data from the Cochrane database for chronic pain. DATA SYNTHESIS: No single drug was mentioned by either guideline to treat this comorbidity. However, carbamazepine was the only drug that has guideline-supported robust efficacy in the management of each condition separately. CONCLUSIONS: Carbamazepine was found to have strong preclinical data for the treatment of comorbid bipolar mood disorder and chronic pain disorders. While requiring more studies in this population, we propose that this treatment modality may benefit patients.

20.
Curr Protoc Cytom ; Chapter 2: 2.20.1-2.20.11, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23292708

RESUMEN

Super-resolution microscopy overcomes diffraction to generate images with superior resolution compared to conventional light microscopy. Localization-based super-resolution methods result in up to ten-fold improvement in resolution by determining the positions of fluorescent molecules with sub-pixel accuracy. This process critically depends on controlled emission at the level of individual fluorophores so that fluorescence is non-overlapping, allowing for accurate centroid determination of diffraction-limited spots by Gaussian fitting of the pixel intensities. The intrinsic photoswitching behavior of many fluorophores provides a convenient way to achieve emitter isolation. Here, we describe methods for label preparation and staining of cellular structures to obtain high-quality images using localization super resolution. We also compare labeling strategies and dye characteristics relevant to all localization-based techniques, such as STORM and PALM.


Asunto(s)
Aumento de la Imagen , Microscopía/instrumentación , Microscopía/métodos , Animales , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Humanos , Citometría de Imagen/instrumentación , Citometría de Imagen/métodos , Aumento de la Imagen/instrumentación , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Fluorescente/instrumentación , Microscopía Fluorescente/métodos , Microtúbulos/química , Microtúbulos/ultraestructura , Mitocondrias/química , Mitocondrias/ultraestructura , Práctica Profesional , Coloración y Etiquetado/métodos
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