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Schizophrenia is a serious mental disorder, and existing antipsychotic drugs show limited efficacy and cause unwanted side effects. The development of glutamatergic drugs for schizophrenia is currently challenging. Most functions of histamine in the brain are mediated by the histamine H1 receptor; however, the role of the H2 receptor (H2R) is not quite clear, especially in schizophrenia. Here, we found that expression of H2R in glutamatergic neurons of the frontal cortex was decreased in schizophrenia patients. Selective knockout of the H2R gene (Hrh2) in glutamatergic neurons (CaMKIIα-Cre; Hrh2 fl/fl) induced schizophrenia-like phenotypes including sensorimotor gating deficits, increased susceptibility to hyperactivity, social withdrawal, anhedonia, and impaired working memory, as well as decreased firing of glutamatergic neurons in the medial prefrontal cortex (mPFC) in in vivo electrophysiological tests. Selective knockdown of H2R in glutamatergic neurons in the mPFC but not those in the hippocampus also mimicked these schizophrenia-like phenotypes. Furthermore, electrophysiology experiments established that H2R deficiency decreased the firing of glutamatergic neurons by enhancing the current through hyperpolarization-activated cyclic nucleotide-gated channels. In addition, either H2R overexpression in glutamatergic neurons or H2R agonism in the mPFC counteracted schizophrenia-like phenotypes in an MK-801-induced mouse model of schizophrenia. Taken together, our results suggest that deficit of H2R in mPFC glutamatergic neurons may be pivotal to the pathogenesis of schizophrenia and that H2R agonists can be regarded as potentially efficacious medications for schizophrenia therapy. The findings also provide evidence for enriching the conventional glutamate hypothesis for the pathogenesis of schizophrenia and improve the understanding of the functional role of H2R in the brain, especially in glutamatergic neurons.
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Histamina , Esquizofrenia , Ratones , Animales , Histamina/metabolismo , Neuronas/metabolismo , Receptores Histamínicos H2 , Memoria a Corto PlazoRESUMEN
Microglia regulate synaptic function in various ways, including the microglial displacement of the surrounding GABAergic synapses, which provides important neuroprotection from certain diseases. However, the physiological role and underlying mechanisms of microglial synaptic displacement remain unclear. In this study, we observed that microglia exhibited heterogeneity during the displacement of GABAergic synapses surrounding neuronal soma in different cortical regions under physiological conditions. Through three-dimensional reconstruction, in vitro co-culture, two-photon calcium imaging, and local field potentials recording, we found that IL-1ß negatively modulated microglial synaptic displacement to coordinate regional heterogeneity in the motor cortex, which impacted the homeostasis of the neural network and improved motor learning ability. We used the Cre-Loxp system and found that IL-1R1 on glutamatergic neurons, rather than that on microglia or GABAergic neurons, mediated the negative effect of IL-1ß on synaptic displacement. This study demonstrates that IL-1ß is critical for the regional heterogeneity of synaptic displacement by coordinating different actions of neurons and microglia via IL-1R1, which impacts both neural network homeostasis and motor learning ability. It provides a theoretical basis for elucidating the physiological role and mechanism of microglial displacement of GABAergic synapses.
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Aprendizaje , Microglía , Calcio , Neuronas GABAérgicas , Interleucina-1beta , SinapsisRESUMEN
Recent studies based on animal models of various neurological disorders have indicated that mitophagy, a selective autophagy that eliminates damaged and superfluous mitochondria through autophagic degradation, may be involved in various neurological diseases. As an important mechanism of cellular stress response, much less is known about the role of mitophagy in stress-related mood disorders. Here, we found that tumor necrosis factor-α (TNF-α), an inflammation cytokine that plays a particular role in stress responses, impaired the mitophagy in the medial prefrontal cortex (mPFC) via triggering degradation of an outer mitochondrial membrane protein, NIP3-like protein X (NIX). The deficits in the NIX-mediated mitophagy by TNF-α led to the accumulation of damaged mitochondria, which triggered synaptic defects and behavioral abnormalities. Genetic ablation of NIX in the excitatory neurons of mPFC caused passive coping behaviors to stress, and overexpression of NIX in the mPFC improved TNF-α-induced synaptic and behavioral abnormalities. Notably, ketamine, a rapid on-set and long-lasting antidepressant, reversed the TNF-α-induced behavioral abnormalities through activation of NIX-mediated mitophagy. Furthermore, the downregulation of NIX level was also observed in the blood of major depressive disorder patients and the mPFC tissue of animal models. Infliximab, a clinically used TNF-α antagonist, alleviated both chronic stress- and inflammation-induced behavioral abnormalities via restoring NIX level. Taken together, these results suggest that NIX-mediated mitophagy links inflammation signaling to passive coping behaviors to stress, which underlies the pathophysiology of stress-related emotional disorders.
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A fluorescent and colorimetric dual-mode strategy based on carbon dots (CDs) was rationally designed for sensitive determination of Cu2+. Green fluorescent CDs with high absolute quantum yield of 72.9% were synthesized by facile one-step hydrothermal treatment of triethylenetetramine and Rose Bengal. Cu2+ could trigger the oxidative and chromogenic reaction of p-phenylenediamine (PPD) to generate chromogenic PPDox, accompanied by the fluorescence quenching of the CDs. The quenching mechanism was identified as the inner filter effect between PPDox and CDs. Therefore, a colorimetric/fluorescent dual-mode detection method for Cu2+ recognition was constructed. The limits of detection for Cu2+ were 4.14 µM and 1.28 µM for colorimetric and fluorescent mode, respectively. In addition, this method had achieved satisfactory results in the detection of Cu2+ in real serum samples.
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We aimed to build cellular aggregates of TS/A and normal fibroblasts (LX-2) or CAFs (ME-iLX-2), verifying the value of this model in the screening of anticancer drugs and demonstrating the effect of CD44 on aggregate formation. We improved soft agar culture medium to coculture CAFs (NFs) and TS/A and compared the amount and area of cellular aggregates. Eugenol was added to this model to test its value. The transcription of human CD44 was analyzed through RT-qPCR. Cellular aggregates were formed, and both the amount and area of aggregates in the TS/A-ME-iLX-2 coculture group were higher than those in other groups. The eugenol inhibited the formation of TS/A-fibroblasts aggregates. Human CD44 was highly transcripted in TS/A-ME-iLX-2 aggregates. Cocultured cellular aggregates of fibroblasts and TS/A were successfully formed in the improved soft agar culture medium, and the promotion effect of CAFs on cancer cells was further confirmed. The eugenol test showed its value in the screening of anticancer drugs. The RT-qPCR results demonstrated the important effect of CD44 on aggregate formation.
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Neoplasias de la Mama , Humanos , Animales , Ratones , Femenino , Agar , Eugenol , Fibroblastos , Técnicas de Cocultivo , Línea Celular Tumoral , Medios de Cultivo , Proliferación CelularRESUMEN
Bortezomib (BTZ) is a proteasome inhibitor serves as a first-line drug for multiple myeloma treatment. BTZ-induced peripheral neuropathy (BIPN) is the most common adverse effect of BTZ with an incidence as high as 40-60%. However, the pathological mechanisms underlying BIPN remain largely unclear. BTZ leads to dramatic Schwann cell demyelination in sciatic nerves. Previous studies implied that myelin debris was predominantly degraded via autophagy-lysosome pathway in Schwann cells. However, the association of autophagy with BIPN has not been made. Mice were treated with BTZ (2 mg/kg, i.v.) on Day1 and Day4 each week for continuous 4 weeks. BTZ-treated mice showed enhanced mechanical hyperalgesia, decreased tail nerve conduction and sciatic nerve demyelination. Unexpectedly, BTZ led to the accumulation of autophagic vesicles, LC3-II and p62 in the sciatic nerve. Moreover, BTZ blocked autophagic flux in RSC96 Schwann cells as determined by mcherry-GFP-LC3 assay, suggesting BTZ may impair lysosomal function rather than inducing autophagy in Schwann cells. BTZ significantly reduced the lysosomal activity in Schwann cells as determined by reduced LysoTracker Red and DQ-Red-BSA staining and increased the level of immature Cathepsin B (CTSB). Remarkably, lysosomal activators PP242 and Torin1, significantly reversed the blockage of autophagic flux by BTZ. We further verified that Torin1 rescued the demyelination, nerve conduction and reduced the mechanical hyperalgesia in BIPN mice. Additionally, Torin1 did not compromise the efficacy of BTZ in suppressing multiple myeloma RPMI8226 cell. Taken together, we identified that lysosomal dysfunction in Schwann cells caused by BTZ is involved in the BIPN pathology. Improved lysosomal function in Schwann cells can be a promising strategy for BIPN treatment.
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Enfermedades Desmielinizantes , Mieloma Múltiple , Síndromes de Neurotoxicidad , Ratones , Animales , Bortezomib/efectos adversos , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Hiperalgesia/inducido químicamente , Células de Schwann/patología , Síndromes de Neurotoxicidad/patología , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/patologíaRESUMEN
OBJECTIVE: To explore the frequency and effect of extreme temperature on the non-accidental death rate in Hulunbuir, a Chinese ice city. METHODS: From 2014 to 2018, mortality data of residents residing in Hulunbuir City were collected. The lag and cumulative effects of extreme temperature conditions on non-accidental death and respiratory and circulatory diseases were analyzed by distributed lag non-linear models (DLNM). RESULTS: The risk of death was the highest during high-temperature conditions, the RR value was 1.111 (95% CI 1.031 ~ 1.198). The effect was severe and acute. The risk of death during extreme low-temperature conditions peaked on the fifth day, (RR 1.057; 95% CI 1.012 ~ 1.112), then decreased and was maintained for 12 days. The cumulative RR value was 1.289 (95% CI 1.045 ~ 1.589). Heat significantly influenced the incidence of non-accidental death in both men (RR 1.187; 95% CI 1.059-1.331) and women (RR 1.252; 95% CI 1.085-1.445). CONCLUSIONS: Regardless of the temperature effect, the risk of death in the elderly group (≥ 65 years) was significantly higher than that of the young group (0-64 years). High-temperature and low-temperature conditions can contribute to the increased number of deaths in Hulunbei. While high-temperature has an acute effect, low-temperature has a lagging effect. Elderly and women, as well as people with circulatory diseases, are more sensitive to extreme temperatures.
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Enfermedades Cardiovasculares , Dinámicas no Lineales , Masculino , Humanos , Femenino , Anciano , Temperatura , Estudios Longitudinales , Frío , Calor , China/epidemiologíaRESUMEN
Our previous study showed that H3 receptor antagonists reduced neuronal apoptosis and cerebral infarction in the acute stage after cerebral ischemia, but through an action independent of activation of histaminergic neurons. Because enhanced angiogenesis facilitates neurogenesis and neurological recovery after ischemic stroke, we herein investigated whether antagonism of H3R promoted angiogenesis after brain ischemia. Photothrombotic stroke was induced in mice. We showed that administration of H3R antagonist thioperamide (THIO, 10 mg·kg-1·d-1, i.p., from D1 after cerebral ischemia) significantly improved angiogenesis assessed on D14, and attenuated neurological defects on D28 after cerebral ischemia. Compared with wild-type mice, Hrh3-/- mice displayed more blood vessels in the ischemic boundary zone on D14, and THIO administration did not promote angiogenesis in these knockout mice. THIO-promoted angiogenesis in mice was reversed by i.c.v. injection of H3R agonist immepip, but not by H1 and H2 receptor antagonists, histidine decarboxylase inhibitor α-fluoromethylhistidine, or histidine decarboxylase gene knockout (HDC-/-), suggesting that THIO-promoted angiogenesis was independent of activation of histaminergic neurons. In vascular endothelial cells (bEnd.3), THIO (10-9-10-7 M) dose-dependently facilitated cell migration and tube formation after oxygen glucose deprivation (OGD), and H3R knockdown caused similar effects. We further revealed that H3R antagonism reduced the interaction between H3R and Annexin A2, while knockdown of Annexin A2 abrogated THIO-promoted angiogenesis in bEnd.3 cells after OGD. Annexin A2-overexpressing mice displayed more blood vessels in the ischemic boundary zone, which was reversed by i.c.v. injection of immepip. In conclusion, this study demonstrates that H3R antagonism promotes angiogenesis after cerebral ischemia, which is independent of activation of histaminergic neurons, but related to the H3R on vascular endothelial cells and its interaction with Annexin A2. Thus, H3R antagonists might be promising drug candidates to improve angiogenesis and neurological recovery after ischemic stroke.
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Anexina A2 , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Receptores Histamínicos H3 , Animales , Ratones , Histidina Descarboxilasa/genética , Histidina Descarboxilasa/metabolismo , Receptores Histamínicos H3/metabolismo , Histamina , Células Endoteliales/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Ratones Noqueados , Infarto CerebralRESUMEN
Sevoflurane inhalation is prone to initiate cognitive deficits in infants. The early growth response-2 (Egr-2) gene is DNA-binding transcription factor, involving in cognitive function. In this study we explored the molecular mechanisms underlying the vulnerability to cognitive deficits after sevoflurane administration. Six-day-old (young) and 6-week-old (early adult) mice received anesthesia with 3% sevoflurane for 2 h daily for 3 days. We showed that multiple exposures of sevoflurane induced significant learning ability impairment in young but not early adult mice, assessed in Morris water maze test on postnatal days 65. The integrated differential expression analysis revealed distinct transcription responses of Egr family members in the hippocampus of the young and early adult mice after sevoflurane administration. Particularly, Egr2 was significantly upregulated after sevoflurane exposure only in young mice. Microinjection of Egr2 shRNA recombinant adeno-associated virus into the dentate gyrus alleviated sevoflurane-induced cognitive deficits, and abolished sevoflurane-induced dendritic spins loss and BDNF downregulation in young mice. On the contrary, microinjection of the Egr2 overexpression virus in the dentate gyrus aggravated learning ability impairment induced by sevoflurane in young mice but not early adult mice. Furthermore, we revealed that sevoflurane markedly upregulated the nuclear factors of activated T-cells NFATC1 and NFATC2 in young mice, which were involved in Egr2 regulation. In conclusion, Egr2 serves as a critical factor for age-dependent vulnerability to sevoflurane-induced cognitive deficits.
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Anestésicos por Inhalación , Disfunción Cognitiva , Proteína 2 de la Respuesta de Crecimiento Precoz , Éteres Metílicos , Animales , Ratones , Anestésicos por Inhalación/toxicidad , Animales Recién Nacidos , Cognición , Disfunción Cognitiva/inducido químicamente , Proteína 2 de la Respuesta de Crecimiento Precoz/genética , Proteína 2 de la Respuesta de Crecimiento Precoz/metabolismo , Hipocampo/metabolismo , Aprendizaje por Laberinto , Sevoflurano/efectos adversosRESUMEN
Progressive ischemic stroke (PIS) is featured by progressive neurological dysfunction after ischemia. Ischemia-evoked neuroinflammation is implicated in the progressive brain injury after cerebral ischemia, while Caspase-1, an active component of inflammasome, exaggerates ischemic brain injury. Current Caspase-1 inhibitors are inadequate in safety and druggability. Here, we investigated the efficacy of CZL80, a novel Caspase-1 inhibitor, in mice with PIS. Mice and Caspase-1-/- mice were subjected to photothrombotic (PT)-induced cerebral ischemia. CZL80 (10, 30 mg·kg-1·d-1, i.p.) was administered for one week after PT onset. The transient and the progressive neurological dysfunction (as foot faults in the grid-walking task and forelimb symmetry in the cylinder task) was assessed on Day1 and Day4-7, respectively, after PT onset. Treatment with CZL80 (30 mg/kg) during Day1-7 significantly reduced the progressive, but not the transient neurological dysfunction. Furthermore, we showed that CZL80 administered on Day4-7, when the progressive neurological dysfunction occurred, produced significant beneficial effects against PIS, suggesting an extended therapeutic time-window. CZL80 administration could improve the neurological function even as late as Day43 after PT. In Caspase-1-/- mice with PIS, the beneficial effects of CZL80 were abolished. We found that Caspase-1 was upregulated during Day4-7 after PT and predominantly located in activated microglia, which was coincided with the progressive neurological deficits, and attenuated by CZL80. We showed that CZL80 administration did not reduce the infarct volume, but significantly suppressed microglia activation in the peri-infarct cortex, suggesting the involvement of microglial inflammasome in the pathology of PIS. Taken together, this study demonstrates that Caspase-1 is required for the progressive neurological dysfunction in PIS. CZL80 is a promising drug to promote the neurological recovery in PIS by inhibiting Caspase-1 within a long therapeutic time-window.
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Lesiones Encefálicas , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Ratones , Animales , Inflamasomas , Modelos Animales de Enfermedad , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/patología , Microglía , Infarto Cerebral , Caspasa 1 , Lesiones Encefálicas/patología , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/patología , Ratones Endogámicos C57BLRESUMEN
BACKGROUND AND PURPOSE: We present a retrospective analysis of patients who underwent minimally invasive endoscopic intracerebral hemorrhage (ICH) evacuation to identify variables that were associated with long-term outcome. METHODS: Minimally invasive endoscopic ICH evacuation was performed on patients with supratentorial ICH who fit prespecified clinical inclusion and exclusion criteria. Demographic, clinical, and radiographic factors previously demonstrated to impact functional outcome in ICH were included in a univariate analysis to identify factors associated with favorable outcome (modified Rankin Scale score, 0-3) at 6 months. Factors associated with a favorable outcome in the univariate analysis (P≤0.20) were included in a multivariate logistic regression analysis with the same dependent variable. RESULTS: Ninety patients underwent MIS endoscopic ICH evacuation within 72 hours of ictus. In a multivariate analysis, factors associated with good long-term functional outcome included time to evacuation (per hour; OR, 0.95 [95% CI, 0.92-0.98], P=0.004), age (per decade, odds ratio [OR], 0.49 [95% CI, 0.28-0.77], P=0.005), presence of intraventricular hemorrhage (OR, 0.15 [95% CI, 0.04-0.47], P=0.002), and lobar location (OR, 18.5 [95% CI, 4.5-103], P=0.0005). Early evacuation was not associated with an increased risk of rebleeding. CONCLUSIONS: Young age, lack of intraventricular hemorrhage, lobar location, and time to evacuation were independently associated with good long-term functional outcome in patients undergoing minimally invasive endoscopic ICH evacuation. The OR for time to evacuation suggests that for each additional hour, there was a 5% reduction in the odds of achieving a favorable outcome.
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Hemorragia Cerebral/cirugía , Hematoma/cirugía , Accidente Cerebrovascular/cirugía , Resultado del Tratamiento , Adulto , Anciano , Hemorragia Cerebral/complicaciones , Craneotomía/métodos , Hematoma/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Oportunidad RelativaRESUMEN
BACKGROUND AND PURPOSE: Endovascular thrombectomy for large vessel occlusion stroke is a time-sensitive intervention. The use of a Mobile Interventional Stroke Team (MIST) traveling to Thrombectomy Capable Stroke Centers to perform endovascular thrombectomy has been shown to be significantly faster with improved discharge outcomes, as compared with the drip-and-ship (DS) model. The effect of the MIST model stratified by time of presentation has yet to be studied. We hypothesize that patients who present in the early window (last known well of ≤6 hours) will have better clinical outcomes in the MIST model. METHODS: The NYC MIST Trial and a prospectively collected stroke database were assessed for patients undergoing endovascular thrombectomy from January 2017 to February 2020. Patients presenting in early and late time windows were analyzed separately. The primary end point was the proportion with a good outcome (modified Rankin Scale score of 0-2) at 90 days. Secondary end points included discharge National Institutes of Health Stroke Scale and modified Rankin Scale. RESULTS: Among 561 cases, 226 patients fit inclusion criteria and were categorized into MIST and DS cohorts. Exclusion criteria included a baseline modified Rankin Scale score of >2, inpatient status, or fluctuating exams. In the early window, 54% (40/74) had a good 90-day outcome in the MIST model, as compared with 28% (24/86) in the DS model (P<0.01). In the late window, outcomes were similar (35% versus 41%; P=0.77). The median National Institutes of Health Stroke Scale at discharge was 5.0 and 12.0 in the early window (P<0.01) and 5.0 and 11.0 in the late window (P=0.11) in the MIST and DS models, respectively. The early window discharge modified Rankin Scale was significantly better in the MIST model (P<0.01) and similar in the late window (P=0.41). CONCLUSIONS: The MIST model in the early time window results in better 90-day outcomes compared with the DS model. This may be due to the MIST capturing high-risk fast progressors at an earlier time point. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03048292.
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Isquemia Encefálica/terapia , Intervención Médica Temprana , Accidente Cerebrovascular Isquémico/terapia , Tiempo de Tratamiento , Lesiones del Sistema Vascular/terapia , Intervención Médica Temprana/métodos , Procedimientos Endovasculares/métodos , Humanos , Recuperación de la Función/fisiología , Accidente Cerebrovascular , Trombectomía/métodos , Resultado del TratamientoRESUMEN
Cellulose is one of the most abundant organic polymers in nature. It contains multiple ß-1,4-glucan chains synthesized by cellulose synthases (CesAs) on the plasma membrane of higher plants. CesA subunits assemble into a pseudo-sixfold symmetric cellulose synthase complex (CSC), known as a 'rosette complex'. The structure of CesA remains enigmatic. Here, we report the cryo-EM structure of the homotrimeric CesA7 from Gossypium hirsutum at 3.5-angstrom resolution. The GhCesA7 homotrimer shows a C3 symmetrical assembly. Each protomer contains seven transmembrane helices (TMs) which form a channel potentially facilitating the release of newly synthesized glucans. The cytoplasmic glycosyltransferase domain (GT domain) of GhCesA7 protrudes from the membrane, and its catalytic pocket is directed towards the TM pore. The homotrimer GhCesA7 is stabilized by the transmembrane helix 7 (TM7) and the plant-conserved region (PCR) domains. It represents the building block of CSCs and facilitates microfibril formation. This structure provides insight into how eukaryotic cellulose synthase assembles and provides a mechanistic basis for the improvement of cotton fibre quality in the future.
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Glucosiltransferasas , Gossypium , Celulosa , Fibra de Algodón , Glucosiltransferasas/genética , Gossypium/genéticaRESUMEN
BACKGROUND AND PURPOSE: Randomized controlled trials have demonstrated the importance of time to endovascular therapy (EVT) in clinical outcomes in large vessel occlusion (LVO) acute ischemic stroke. Delays to treatment are particularly prevalent when patients require a transfer from hospitals without EVT capability onsite. A computer-aided triage system, Viz LVO, has the potential to streamline workflows. This platform includes an image viewer, a communication system, and an artificial intelligence (AI) algorithm that automatically identifies suspected LVO strokes on CTA imaging and rapidly triggers alerts. We hypothesize that the Viz application will decrease time-to-treatment, leading to improved clinical outcomes. METHODS: A retrospective analysis of a prospectively maintained database was assessed for patients who presented to a stroke center currently utilizing Viz LVO and underwent EVT following transfer for LVO stroke between July 2018 and March 2020. Time intervals and clinical outcomes were compared for 55 patients divided into pre- and post-Viz cohorts. RESULTS: The median initial door-to-neuroendovascular team (NT) notification time interval was significantly faster (25.0 min [IQR = 12.0] vs. 40.0 min [IQR = 61.0]; p = 0.01) with less variation (p < 0.05) following Viz LVO implementation. The median initial door-to-skin puncture time interval was 25 min shorter in the post-Viz cohort, although this was not statistically significant (p = 0.15). CONCLUSIONS: Preliminary results have shown that Viz LVO implementation is associated with earlier, more consistent NT notification times. This application can serve as an early warning system and a failsafe to ensure that no LVO is left behind.
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Inteligencia Artificial , Angiografía Cerebral , Angiografía por Tomografía Computarizada , Técnicas de Apoyo para la Decisión , Diagnóstico por Computador , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Triaje , Anciano , Anciano de 80 o más Años , Toma de Decisiones Clínicas , Bases de Datos Factuales , Prestación Integrada de Atención de Salud , Procedimientos Endovasculares , Femenino , Humanos , Accidente Cerebrovascular Isquémico/terapia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Tiempo de Tratamiento , Flujo de TrabajoRESUMEN
Thanks to the advances in optical microscope technology and our knowledge of autophagic biomarkers, single-molecule events of autophagy are now accessible to human eyes. Different proteins are involved hierarchically in the biogenesis and maturation of autophagosomes. Detecting these autophagy-related proteins either by immunostaining or fluorescent protein labelling makes the dynamic autophagic process visible. However, low antibody specificity and weak endogenous expression of autophagy-related proteins in certain tissues limit the applicability of immunostaining in autophagy detection. To cope with this, live-cell imaging combined with various fluorescent probes has been developed and employed in monitoring autophagy. As the most widely used autophagic biomarker, LC3 can be used to visualize autophagosomes, and fluorescent probes targeting LC3, i.e., RFP/mCherry-GFP-LC3, and GFP-LC3-RFP-LC3ΔG, can examine autophagy flux dynamically and quantitatively. In addition, the application of novel fluorophores such as Keima helps to detect the temporal and spatial characteristics of autophagy. Furthermore, selective autophagy can be clarified by labelling corresponding substrates and autophagosomes or lysosomes simultaneously. With the help of two-photon microscopy, the process of autophagy in live animals has been uncovered. Here, we summarize the methods for observing autophagy by optical microscopy and the selection of fluorescent markers.
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Autofagia , Proteínas Asociadas a Microtúbulos , Animales , Autofagosomas , Proteínas Fluorescentes Verdes , Humanos , Lisosomas , Proteínas Asociadas a Microtúbulos/genéticaRESUMEN
BACKGROUND AND PURPOSE: Triage of patients with emergent large vessel occlusion stroke to primary stroke centers followed by transfer to comprehensive stroke centers leads to increased time to endovascular therapy. A Mobile Interventional Stroke Team (MIST) provides an alternative model by transferring a MIST to a Thrombectomy Capable Stroke Center (TSC) to perform endovascular therapy. Our aim is to determine whether the MIST model is more time-efficient and leads to improved clinical outcomes compared with standard drip-and-ship (DS) and mothership models. METHODS: This is a prospective observational cohort study with 3-month follow-up between June 2016 and December 2018 at a multicenter health system, consisting of one comprehensive stroke center, 4 TSCs, and several primary stroke centers. A total of 228 of 373 patients received endovascular therapy via 1 of 4 models: mothership with patient presentation to a comprehensive stroke center, DS with patient transfer from primary stroke center or TSC to comprehensive stroke center, MIST with patient presentation to TSC and MIST transfer, or a combination of DS with patient transfer from primary stroke center to TSC and MIST. The prespecified primary end point was initial door-to-recanalization time and secondary end points measured additional time intervals and clinical outcomes at discharge and 3 months. RESULTS: MIST had a faster mean initial door-to-recanalization time than DS by 83 minutes (P<0.01). MIST and mothership had similar median door-to-recanalization times of 192 minutes and 179 minutes, respectively (P=0.83). A greater proportion had a complete recovery (National Institutes of Health Stroke Scale of 0 or 1) at discharge in MIST compared with DS (37.9% versus 16.7%; P<0.01). MIST had 52.8% of patients with modified Rankin Scale of ≤2 at 3 months compared with 38.9% in DS (P=0.10). CONCLUSIONS: MIST led to significantly faster initial door-to-recanalization times compared with DS, which was comparable to mothership. This decrease in time has translated into improved short-term outcomes and a trend towards improved long-term outcomes. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03048292.
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Servicios Médicos de Urgencia/organización & administración , Accidente Cerebrovascular Isquémico/terapia , Unidades Móviles de Salud/organización & administración , Transferencia de Pacientes/organización & administración , Trombectomía/métodos , Terapia Trombolítica/métodos , Tiempo de Tratamiento/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Trombosis de las Arterias Carótidas/terapia , Atención a la Salud/organización & administración , Procedimientos Endovasculares/métodos , Femenino , Humanos , Infarto de la Arteria Cerebral Media/terapia , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Microplastics (MPs) pollution has drawn increasing concern due to its widespread occurrence and potential risks in the environment. The reliable methods and instruments for fast analysis of microplastics (MPs) less than 5 mm are urgently needed. In this study, a new method based on custom-made portable pyrolysis-mass spectrometry (Pyr-MS) is developed, which enables rapid identification and mass related quantification of MPs. MPs are decomposed in the compact pyrolyzer and then directly analyzed in the portable MS by the chemical fingerprints of polymers including characteristic ions and their special ratio. It avoids the complex extraction and separation procedures of the pyrolysis/thermogravimetric-gas chromatography-mass spectrometry (Pyr/TGA-GC-MS), realizes the rapid analysis of MPs in 5 min, and thus can practically apply to a large number of MPs samples. In comparison to Fourier transform infrared spectroscopy (FT-IR) and Raman, this method is not limited by the shape, size, and color of MPs. Four common plastics including polyethylene (PE), polypropylene (PP), polystyrene (PS), and poly(methyl methacrylate) (PMMA) were investigated to verify the feasibility of this method. The environmental MPs samples collected from a beach were successfully identified and quantified, demonstrating the simplicity and practicality of this approach. The influence of plastics aging on the chemical fingerprints and the potential of mixed plastics detection by Pyr-MS are also assessed. The portable Pyr-MS could provide a promising tool for in-field analysis of MPs such as ship-based marine MPs surveys.
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The cotton fibre serves as a valuable experimental system to study cell wall synthesis in plants, but our understanding of the genetic regulation of this process during fibre development remains limited. We performed a genome-wide association study (GWAS) and identified 28 genetic loci associated with fibre quality in allotetraploid cotton. To investigate the regulatory roles of these loci, we sequenced fibre transcriptomes of 251 cotton accessions and identified 15 330 expression quantitative trait loci (eQTL). Analysis of local eQTL and GWAS data prioritised 13 likely causal genes for differential fibre quality in a transcriptome-wide association study (TWAS). Characterisation of distal eQTL revealed unequal genetic regulation patterns between two subgenomes, highlighted by an eQTL hotspot (Hot216) that established a genome-wide genetic network regulating the expression of 962 genes. The primary regulatory role of Hot216, and specifically the gene encoding a KIP-related protein, was found to be the transcriptional regulation of genes responsible for cell wall synthesis, which contributes to fibre length by modulating the developmental transition from rapid cell elongation to secondary cell wall synthesis. This study uncovered the genetic regulation of fibre-cell development and revealed the molecular basis of the temporal modulation of secondary cell wall synthesis during plant cell elongation.
Asunto(s)
Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Pared Celular/genética , Fibra de Algodón , Redes Reguladoras de Genes , Gossypium/genética , Sitios de Carácter Cuantitativo/genéticaRESUMEN
Melatonin receptors (MTs) are potential drug targets for stroke therapy. Ramelteon is a selective melatonin receptor agonist used to treat insomnia. In this study we investigated whether ramelteon could attenuate cerebral ischemia in mice. Acute focal cerebral ischemia was induced in mice via middle cerebral artery occlusion (MCAO). We found oral administration of ramelteon (3.0 mg/kg) significantly attenuated ischemic injury even when it was given 4 h after the onset of ischemia. We showed that administration of ramelteon (3.0 mg/kg) displayed comparable protective efficacy and length of effective time window as administration of edaravone (10 mg/kg, i.p.), which was used in clinic to treat ischemic stroke. Chronic ischemic brain injury was induced in mice using photothrombosis. Oral administration of ramelteon (3.0 mg · kg-1 · d-1) for 7 days after ischemia significantly attenuated functional deficits for at least 15 days. The neuroprotection of ramelteon was blocked by 4-P-PDOT, a specific MT antagonist. We further revealed that ramelteon significantly inhibited autophagy in the peri-infarct cortex in both the mouse ischemia models via regulating AMPK/mTOR signaling pathway. Intracerebroventricular injection of rapamycin, an autophagy activator, compromised the neuroprotection of ramelteon, suggesting ramelteon might attenuate ischemic injury by counteracting autophagic cell death. These data demonstrate for the first time the potential benefits of ramelteon in the treatment of both acute and chronic ischemic brain injury and provide the rationale for the application of ramelteon in stroke therapy.
Asunto(s)
Lesión Encefálica Crónica/tratamiento farmacológico , Indenos/uso terapéutico , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Receptores de Melatonina/agonistas , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Autofagia/efectos de los fármacos , Encéfalo/patología , Lesión Encefálica Crónica/patología , Edaravona/uso terapéutico , Infarto de la Arteria Cerebral Media/patología , Ratones , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Mitochondrial encephalomyopathies are a group of disorders affecting skeletal muscles and brain. Although the symptoms vary among these disorders, mitochondrial DNA mutation or loss is the common characteristic. The abnormality of mitochondrial genome usually causes the dysfunction of mitochondrial respiratory and even mitochondrial damage. As a critical way of degradation, attention has been paid to the involvement of autophagy in encephalomyopathies. Autophagy is found activated in these encephalomyopathies-relevant cells as a compensatory manner to eliminate these damaged and dysfunctional mitochondria. However, accumulating evidences indicate that autophagy is incompetent to clear them. The insufficient mitophagy may ultimately accelerate cell death. Here we discuss the involvement of autophagy in encephalomyopathies based on the current evidence. We further look into the future to rescue encephalomyopathies by regulating autophagy. Only five encephalomyopathies are included in this chapter due to the availability of evidence. Nevertheless, these encephalomyopathies share a variety of common features and autophagy may also be regulated in the other encephalomyopathies.