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An increase in ambient temperature leads to an increase in sleep. However, the mechanisms behind this phenomenon remain unknown. This study aimed to investigate the role of microglia in the increase of sleep caused by high ambient temperature. We confirmed that at 35 °C, slow-wave sleep was significantly increased relative to those observed at 25 °C. Notably, this effect was abolished upon treatment with PLX3397, a CSF1R inhibitor that can deplete microglia, while sleep amount at 25 °C was unaffected. These observations suggest that microglia play a pivotal role in modulating the homeostatic regulation of sleep in response to the fluctuations in ambient temperature.
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Calor , Microglía , Sueño de Onda Lenta , Animales , Aminopiridinas/farmacología , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Microglía/fisiología , Sueño de Onda Lenta/efectos de los fármacos , Sueño de Onda Lenta/fisiología , RatonesRESUMEN
In the terahertz (THz) band, modulation research has become a focal point, with precise control of the phase shift of THz waves playing a pivotal role. In this study, we investigate the optical control of THz phase shift modulation in a polydimethylsiloxane (PDMS)-vanadium dioxide (VO2) flexible material using THz time-domain spectroscopy. Under the influence of an 808-nm continuous wave (CW) laser with power densities ranging from 0 to 2.74 W/cm2, the PDMS-VO2 flexible material exhibits significant phase shift modulation in the frequency range of 0.2 to 1.0 THz. The maximum optical-pumping phase shift reaches 0.27π rad at 1.0 THz in a composite material with a VO2 mass fraction of 5% and a thickness of 360â µm, and the amplitude transmittance from 0.2 THz to 1.0 THz exceeds 70%. Furthermore, the composite material exhibits good stability under at least 640 switching cycle times, as confirmed through repeatability tests. The proposed composite devices offer a new approach for more flexible phase shift modulation owing to the flexibility of the composite material and the non-contact and precise modulation of light control. Additionally, the stress-adjustable characteristics of flexible materials make them highly suitable for use in wearable THz modulators, highlighting their significant application potential.
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BACKGROUND: G protein-coupled receptors play a critical role in atrial fibrillation (AF). Spexin is a novel ligand of galanin receptors (GALRs). In this study, we investigated the regulation of spexin and GALRs on AF and the underlying mechanisms. METHODS: Global spexin knockout (SPX-KO) and cardiomyocyte-specific GALRs knockout (GALR-cKO) mice underwent burst pacing electrical stimulation. Optical mapping was used to determine atrial conduction velocity and action potential duration. Atrial myocyte action potential duration and inward rectifying K+ current (IK1) were recorded using whole-cell patch clamps. Isolated cardiomyocytes were stained with Fluo-3/AM dye, and intracellular Ca2+ handling was examined by CCD camera. A mouse model of AF was established by Ang-II (angiotensin II) infusion. RESULTS: Spexin plasma levels in patients with AF were lower than those in subjects without AF, and knockout of spexin increased AF susceptibility in mice. In the atrium of SPX-KO mice, potassium inwardly rectifying channel subfamily J member 2 (KCNJ2) and sarcolipin (SLN) were upregulated; meanwhile, IK1 current was increased and Ca2+ handling was impaired in isolated atrial myocytes of SPX-KO mice. GALR2-cKO mice, but not GALR1-cKO and GALR3-cKO mice, had a higher incidence of AF, which was associated with higher IK1 current and intracellular Ca2+ overload. The phosphorylation level of CREB (cyclic AMP responsive element binding protein 1) was upregulated in atrial tissues of SPX-KO and GALR2-cKO mice. Chromatin immunoprecipitation confirmed the recruitment of p-CREB to the proximal promoter regions of KCNJ2 and SLN. Finally, spexin treatment suppressed CREB signaling, decreased IK1 current and decreased intracellular Ca2+ overload, which thus reduced the inducibility of AF in Ang-II-infused mice. CONCLUSIONS: Spexin reduces atrial fibrillation susceptibility by inhibiting CREB phosphorylation and thus downregulating KCNJ2 and SLN transcription by GALR2 receptor. The spexin/GALR2/CREB signaling pathway represents a novel therapeutic avenue in the development of agents against atrial fibrillation.
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Fibrilación Atrial , Ratones Noqueados , Miocitos Cardíacos , Hormonas Peptídicas , Receptor de Galanina Tipo 2 , Animales , Femenino , Humanos , Masculino , Ratones , Potenciales de Acción/efectos de los fármacos , Fibrilación Atrial/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Hormonas Peptídicas/metabolismo , Receptor de Galanina Tipo 2/metabolismo , Receptor de Galanina Tipo 2/genética , Transducción de SeñalRESUMEN
Microglia are the residential immune cells in the central nervous system. Their roles as innate immune cells and regulators of synaptic remodeling are critical to the development and the maintenance of the brain. Numerous studies have depleted microglia to elucidate their involvement in healthy and pathological conditions. PLX3397, a blocker of colony stimulating factor 1 receptor (CSF1R), is widely used to deplete mouse microglia due to its non-invasiveness and convenience. Recently, other small rodents, including Syrian hamsters (Mesocricetus auratus) and Mongolian gerbils (Meriones unguiculatus), have been recognized as valuable animal models for studying brain functions and diseases. However, whether microglia depletion via PLX3397 is feasible in these species remains unclear. Here, we administered PLX3397 orally via food pellets to hamsters and gerbils. PLX3397 successfully depleted gerbil microglia but had no effect on microglial density in hamsters. Comparative analysis of the CSF1R amino acid sequence in different species hints that amino acid substitutions in the juxtamembrane domain may potentially contribute to the inefficacy of PLX3397 in hamsters.
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Aminopiridinas , Encéfalo , Gerbillinae , Microglía , Pirroles , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos , Animales , Cricetinae , Administración Oral , Aminopiridinas/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/citología , Mesocricetus , Microglía/efectos de los fármacos , Microglía/metabolismo , Modelos Animales , Pirroles/farmacología , Pirrolidinas/farmacología , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Especificidad de la EspecieRESUMEN
BACKGROUND: Enhancing angiogenesis may be an effective strategy to promote functional recovery after ischemic stroke. Inflammation regulates angiogenesis. Microglia are crucial cells that initiate inflammatory responses after various brain injuries. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays a role in regulating brain injury. This study aimed to explore the effects of NEAT1-regulated microglial polarization on the neovascularization capacity of cerebrovascular endothelial cells and the underlying molecular regulatory mechanisms. METHODS: Mouse cerebral arterial endothelial cells (mCAECs) were co-cultured with BV-2 cells in different groups using a Transwell system. NEAT1 expression levels were measured by fluorescence quantitative reverse transcription PCR. Levels of IL-1ß, IL-6, TNF-α, Arg-1, IL-4, and IL-10 were determined using ELISA. Expression levels of CD86 and CD163 were detected by immunofluorescence. The neovascularization capacity of mCAECs was assessed using CCK-8, Transwell, Transwell-matrigel, and tube formation assays. Label-free quantification proteomics was carried out to identify differentially expressed proteins. Protein levels were measured by Western blotting. RESULTS: NEAT1 overexpression induced M1 polarization in BV-2 cells, whereas NEAT1 knockdown blocked lipopolysaccharide-induced M1 polarization in microglia. NEAT1-overexpressing BV-2 cells suppressed the angiogenic ability of mCAECs, and NEAT1-knocking BV-2 cells promoted the angiogenic ability of mCAECs under lipopolysaccharide treatment. Label-free quantitative proteomic analysis identified 144 upregulated and 131 downregulated proteins that were induced by NEAT1 overexpression. The AMP-activated protein kinase (AMPK) signaling pathway was enriched in the Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed proteins. Further verification showed that NEAT1 inactivated the AMPK signaling pathway. Moreover, the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleotide reversed the effect of NEAT1 on BV-2 polarization and the regulatory effect of NEAT1-overexpressing BV-2 cells on the angiogenic ability of mCAECs. CONCLUSIONS: NEAT1 inhibits the angiogenic activity of mCAECs by inducing M1 polarization of BV-2 cells through the AMPK signaling pathway. This study further clarified the impact and mechanism of NEAT1 on microglia and the angiogenic ability of cerebrovascular endothelial cells.
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Proteínas Quinasas Activadas por AMP , Células Endoteliales , Microglía , ARN Largo no Codificante , Transducción de Señal , Animales , Microglía/metabolismo , Microglía/efectos de los fármacos , Ratones , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Arterias Cerebrales/metabolismo , Arterias Cerebrales/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Neovascularización Fisiológica/genética , Línea Celular , Polaridad Celular/efectos de los fármacosRESUMEN
Two-dimensional (2D) tin halide perovskites are promising semiconductors for field-effect transistors (FETs) owing to their fascinating electronic properties. However, the correlation between the chemical nature of organic cations and charge carrier transport is still far from understanding. In this study, the influence of chain length of linear alkyl ammonium cations on film morphology, crystallinity, and charge transport in 2D tin halide perovskites is investigated. The carbon chain lengths of the organic spacers vary from propylammonium to heptanammonium. The increase of alkyl chain length leads to enhanced local charge carrier transport in the perovskite film with mobilities of up to 8 cm2 V-1 s-1, as confirmed by optical-pump terahertz spectroscopy. A similar improved macroscopic charge transport is also observed in FETs, only to the chain length of HA, due to the synergistic enhancement of film morphology and molecular organization. While the mobility increases with the temperature rise from 100 K to 200 K due to the thermally activated transport mechanism, the device performance decreases in the temperature range of 200 K to 295 K because of ion migration. These results provide guidelines on rational design principles of organic spacer cations for 2D tin halide perovskites and contribute to other optoelectronic applications.
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Cardiomyocyte maturation is the final stage of heart development, and abnormal cardiomyocyte maturation will lead to serious heart diseases. CXXC zinc finger protein 1 (Cfp1), a key epigenetic factor in multi-lineage cell development, remains underexplored in its influence on cardiomyocyte maturation. This study investigates the role and mechanisms of Cfp1 in this context. Cardiomyocyte-specific Cfp1 knockout (Cfp1-cKO) mice died within 4 weeks of birth. Cardiomyocytes derived from Cfp1-cKO mice showed an inhibited maturation phenotype, characterized by structural, metabolic, contractile, and cell cycle abnormalities. In contrast, cardiomyocyte-specific Cfp1 transgenic (Cfp1-TG) mice and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) overexpressing Cfp1 displayed a more mature phenotype. Mechanistically, deficiency of Cfp1 led to a reduction in trimethylation on lysine 4 of histone H3 (H3K4me3) modification, accompanied by the formation of ectopic H3K4me3. Furthermore, Cfp1 deletion decreased the level of H3K4me3 modification in adult genes and increased the level of H3K4me3 modification in fetal genes. Collectively, Cfp1 modulates the expression of genes crucial to cardiomyocyte maturation by regulating histone H3K4me3 modification, thereby intricately influencing the maturation process. This study implicates Cfp1 as an important molecule regulating cardiomyocyte maturation, with its dysfunction strongly linked to cardiac disease.
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Histonas , Células Madre Pluripotentes Inducidas , Animales , Humanos , Ratones , Histonas/genética , Células Madre Pluripotentes Inducidas/metabolismo , Miocitos Cardíacos/metabolismo , Transactivadores/genética , Transactivadores/metabolismoRESUMEN
Although diurnal animals displaying monophasic sleep patterns exhibit periodic cycles of alternating slow-wave sleep (SWS) and rapid eye movement sleep (REMS), the regulatory mechanisms underlying these regular sleep cycles remain unclear. Here, we report that in the Australian dragon Pogona vitticeps exposed to constant darkness (DD), sleep behavior and sleep-related neuronal activity emerged over a 24-h cycle. However, the regularity of the REMS/SWS alternation was disrupted under these conditions. Notably, when the lizards were then exposed to 12â h of light after DD, the regularity of the sleep stages was restored. These results suggest that sleep-related neuronal activity in lizards is regulated by circadian rhythms and that the regularity of REMS and SWS cycling is influenced by daytime light exposure.
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Electronic devices based on tin halide perovskites often exhibit a poor operational stability. Here, we report an additive engineering strategy to realize high-performance and stable field-effect transistors (FETs) based on 3D formamidinium tin iodide (FASnI3) films. By comparatively studying the modification effects of two additives, i.e., phenethylammonium iodide and 4-fluorophenylethylammonium iodide via combined experimental and theoretical investigations, we unambiguously point out the general effects of phenethylammonium (PEA) and its fluorinated derivative (FPEA) in enhancing crystallization of FASnI3 films and the unique role of fluorination in reducing structural defects, suppressing oxidation of Sn2+ and blocking oxygen and water involved defect reactions. The optimized FPEA-modified FASnI3 FETs reach a record high field-effect mobility of 15.1 cm2/(V·s) while showing negligible hysteresis. The devices exhibit less than 10% and 3% current variation during over 2 h continuous bias stressing and 4200-cycle switching test, respectively, representing the best stability achieved so far for all Sn-based FETs.
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Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder with high morbidity and mortality. The current study aims to explore the role of Cullin-associated and neddylation-dissociated protein 1 (CAND1) in the development of NAFLD and the underlying mechanisms. CAND1 is reduced in the liver of NAFLD male patients and high fat diet (HFD)-fed male mice. CAND1 alleviates palmitate (PA) induced lipid accumulation in vitro. Hepatocyte-specific knockout of CAND1 exacerbates HFD-induced liver injury in HFD-fed male mice, while hepatocyte-specific knockin of CAND1 ameliorates these pathological changes. Mechanistically, deficiency of CAND1 enhances the assembly of Cullin1, F-box only protein 42 (FBXO42) and acetyl-CoA acyltransferase 2 (ACAA2) complexes, and thus promotes the ubiquitinated degradation of ACAA2. ACAA2 overexpression abolishes the exacerbated effects of CAND1 deficiency on NAFLD. Additionally, androgen receptor binds to the -187 to -2000 promoter region of CAND1. Collectively, CAND1 mitigates NAFLD by inhibiting Cullin1/FBXO42 mediated ACAA2 degradation.
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Proteínas Cullin , Enfermedad del Hígado Graso no Alcohólico , Masculino , Animales , Ratones , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Aciltransferasas , Factores de Transcripción/metabolismo , Ubiquitina , Dieta Alta en Grasa/efectos adversos , Ratones Endogámicos C57BL , Hígado/metabolismoRESUMEN
Memory is a fundamental brain function that can be affected by a variety of external factors including environmental pollutants. One of these pollutants is methyl vinyl ketone (MVK), a hazardous substance found in cigarettes, industrial wastes, and car exhaust. Humans can be exposed to MVK under many circumstances; however, it is unclear whether MVK affects higher-order brain functions such as memory. Here, we examined the memory performances of mice receiving systemic MVK administration. We found that 1 mg/kg of MVK impaired spatial memory. We also showed that 1 mg/kg MVK activated glial cells and altered glial functions in several subregions of the hippocampus, a brain region involved in learning and memory. These results suggest that MVK induces memory deficits and activates glial cells in hippocampal subregions.
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Contaminantes Ambientales , Memoria Espacial , Humanos , Animales , Ratones , Administración Cutánea , Hipocampo , NeuroglíaRESUMEN
Microglia, as macrophages in the brain, are responsible for immune responses and synaptic remodeling. Although the function of microglia is regulated by circadian rhythms, it is still unclear whether microglia are involved in the generation and light entrainment of circadian rhythms of behavior. Here, we report that microglial depletion does not alter behavioral circadian rhythms. We depleted ~ 95% of microglia in the mouse brain by PLX3397, a CSF1R inhibitor, and analyzed the effect on the spontaneous behaviors of mice. We found that neither the free-running period under constant darkness nor light entrainment under jet-lag circumstances were influenced by the ablation of microglia. Our results demonstrate that the circadian rhythms of locomotor activity, an important output of the circadian clock in the brain, are likely a phenomenon not produced by microglia.
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Microglía , Núcleo Supraquiasmático , Ratones , Animales , Núcleo Supraquiasmático/fisiología , Ritmo Circadiano , Oscuridad , LocomociónRESUMEN
Light plays an important role in determining plant architecture, which greatly influences crop yield. However, the precise mechanisms by which light signaling regulates bud outgrowth remain to be identified. Here, we show that light regulates bud outgrowth via both HY5 and brassinosteroid (BR)-dependent pathways in tomato. Inactivation of the red-light photoreceptor PHYB, or deficiencies in PHYB or the blue-light photoreceptor CRY1a, inhibits bud outgrowth and leads to decreased accumulation of HY5 protein and increased transcript level of BRANCHED1 (BRC1), a central integrator of branching signals. HY5, functioning as a mobile systemic signal from leaves, promotes bud outgrowth by directly suppressing BRC1 transcript and activating the transcript of BR biosynthesis genes within the lateral buds in tomato. Furthermore, BRC1 prevents the accumulation of cytokinin (CK) and gibberellin (GA) by directly inhibiting the transcript of CK synthesis gene LOG4, while increasing the transcript levels of CK and GA degradation genes (CKX7, GA2ox4, and GA2ox5), leading to an arrest of bud outgrowth. Moreover, bud outgrowth occurs predominantly in the day due to the suppression of BRC1 transcript by HY5. These findings demonstrate that light-inducible HY5 acts as a systemic signaling factor in fine-tuning the bud outgrowth of tomato.
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Solanum lycopersicum , Solanum lycopersicum/genética , Brotes de la Planta , Factores de Transcripción/metabolismo , Citocininas/metabolismo , Hormonas/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
Memory is one of the fundamental cognitive functions of brain. The formation and consolidation of memory depend on the hippocampus and sleep. Sharp wave ripple (SWR) is an electrophysiological event which is most frequently observed in the hippocampus during sleep. It represents a highly synchronized neuronal activity pattern which modulates numerous brain regions including the neocortex, subcortical areas, and the hippocampus itself. In this review, we discuss how SWRs link experiences to memories and what happens in the hippocampus and other brain regions during sleep by focusing on synaptic plasticity.
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Hipocampo , Neocórtex , Hipocampo/fisiología , Sueño/fisiología , Neuronas/fisiología , Plasticidad NeuronalRESUMEN
OBJECTIVE: ASPP1 (apoptosis stimulating of p53 protein 1) is critical in regulating cell apoptosis as a cofactor of p53 to promote its transcriptional activity in the nucleus. However, whether cytoplasmic ASPP1 affects p53 nuclear trafficking and its role in cardiac diseases remains unknown. This study aims to explore the mechanism by which ASPP1 modulates p53 nuclear trafficking and the subsequent contribution to cardiac ischemia/reperfusion (I/R) injury. METHODS AND RESULTS: The immunofluorescent staining showed that under normal condition ASPP1 and p53 colocalized in the cytoplasm of neonatal mouse ventricular cardiomyocytes, while they were both upregulated and translocated to the nuclei upon hypoxia/reoxygenation treatment. The nuclear translocation of ASPP1 and p53 was interdependent, as knockdown of either ASPP1 or p53 attenuated nuclear translocation of the other one. Inhibition of importin-ß1 resulted in the cytoplasmic sequestration of both p53 and ASPP1 in neonatal mouse ventricular cardiomyocytes with hypoxia/reoxygenation stimulation. Overexpression of ASPP1 potentiated, whereas knockdown of ASPP1 inhibited the expression of Bax (Bcl2-associated X), PUMA (p53 upregulated modulator of apoptosis), and Noxa, direct apoptosis-associated targets of p53. ASPP1 was also increased in the I/R myocardium. Cardiomyocyte-specific transgenic overexpression of ASPP1 aggravated I/R injury as indicated by increased infarct size and impaired cardiac function. Conversely, knockout of ASPP1 mitigated cardiac I/R injury. The same qualitative data were observed in neonatal mouse ventricular cardiomyocytes exposed to hypoxia/reoxygenation injury. Furthermore, inhibition of p53 significantly blunted the proapoptotic activity and detrimental effects of ASPP1 both in vitro and in vivo. CONCLUSIONS: Binding of ASPP1 to p53 triggers their nuclear cotranslocation via importin-ß1 that eventually exacerbates cardiac I/R injury. The findings imply that interfering the expression of ASPP1 or the interaction between ASPP1 and p53 to block their nuclear trafficking represents an important therapeutic strategy for cardiac I/R injury.
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Proteínas Adaptadoras Transductoras de Señales , Daño por Reperfusión , Proteína p53 Supresora de Tumor , Animales , Ratones , Apoptosis/fisiología , Hipoxia/metabolismo , Isquemia/metabolismo , Carioferinas , Miocitos Cardíacos/metabolismo , Daño por Reperfusión/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Adaptadoras Transductoras de Señales/genéticaRESUMEN
Antibiotic resistance is a global public health threat, and urgent actions should be undertaken for developing alternative antimicrobial strategies and approaches. Notably, bismuth drugs exhibit potent antimicrobial effects on various pathogens and promising efficacy in tackling SARS-CoV-2 and related infections. As such, bismuth-based materials could precisely combat pathogenic bacteria and effectively treat the resultant infections and inflammatory diseases through a controlled release of Bi ions for targeted drug delivery. Currently, it is a great challenge to rapidly and massively manufacture bismuth-based particles, and yet there are no reports on effectively constructing such porous antimicrobial-loaded particles. Herein, we have developed two rapid approaches (i.e., ultrasound-assisted and agitation-free methods) to synthesizing bismuth-based materials with ellipsoid- (Ellipsoids) and rod-like (Rods) morphologies respectively, and fully characterized physicochemical properties. Rods with a porous structure were confirmed as bismuth metal-organic frameworks (Bi-MOF) and aligned with the crystalline structure of CAU-17. Importantly, the formation of Rods was a 'two-step' crystallization process of growing almond-flake-like units followed by stacking into the rod-like structure. The size of Bi-MOF was precisely controlled from micro-to nano-scales by varying concentrations of metal ions and their ratio to the ligand. Moreover, both Ellipsoids and Rods showed excellent biocompatibility with human gingival fibroblasts and potent antimicrobial effects on the Gram-negative oral pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum. Both Ellipsoids and Rods at 50 âµg/mL could disrupt the bacterial membranes, and particularly eliminate P. gingivalis biofilms. This study demonstrates highly efficient and facile approaches to synthesizing bismuth-based particles. Our work could enrich the administration modalities of metallic drugs for promising antibiotic-free healthcare.
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Carbon/glass fiber-reinforced polymer hybrid composite (HFRP) has the advantages of a light weight and high strength. For the lightweight design of automobile parts, composite parts made of HFRP and polymer materials are increasingly in demand. The method of the injection molding is usually adopted to fabricate composite part with HFRP and polymer materials. The connecting strength between the two materials has an important influence on the service life of the composite part. In this paper, HFRP and polyamide-6 (PA6) were used to fabricate a composite part by the injection molding method. In order to improve the connecting strength between HFRP and PA6, a kind of micro-grooves was fabricated on the HFRP surface. The micro-grooves on the surface of the HFRP provided sufficient adhesion and infiltrating space of molten PA6 material into the mold. In addition, the glass fiber in HFRP can also be used as nucleating agent to facilitate the rapid crystallization of PA6. The micro-grooves on the surface of HFRP were embedded into PA6 like nails, which could improve the connecting strength at the interface effectively. The paper investigated the effects of mold temperature, injection pressure, holding pressure and holding time on the injection quality and connecting strength of composite parts in detail. With a mold temperature of 240 °C, an injection pressure of 8 MPa, a holding pressure of 8 MPa and a holding time of 3 s, the maximum tensile strength of 10.68 MPa was obtained for the composite part. At the effect of micro-grooves, the tensile strength of the composite part could be increased by 126.27%.
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Background: To evaluate the association between blood urea nitrogen (BUN) to creatinine (Cr) (BUN/Cr) ratio and the in-hospital mortality of critically ill patients with cerebral infarction in intensive care unit (ICU). Methods: In this cohort study, the data of 3059 participants with cerebral infarction were collected from the Medical Information Mart for Intensive Care (MIMIC)-III and the MIMIC-IV database. After propensity score matching (PSM) on age and gender, 2085 people were involved in and divided into the alive group (n = 1390) and the dead group (n = 695) based on the results of follow-up. Multivariate logistic analyses were applied to identify the confounders and the association between BUN/Cr and mortality of cerebral infarction. Results: The median follow-up time was 10.5 days. Among 2778 participants, 695 were dead at the end of follow-up. Univariate analysis revealed that BUN/Cr [risk ratio (RR) = 1.01, 95% confidence interval (CI): 1.01-1.02] might be associated with the in-hospital mortality of cerebral infarction patients. After adjusting for respiratory failure, malignant cancer, anticoagulation, liver disease, white blood cell (WBC), red cell distribution width (RDW), glucose, bicarbonate, and temperature, BUN/Cr had week correlation with the increased risk of in-hospital mortality of cerebral infarction patients (RR = 1.01, 95% CI: 1.01-1.02). Conclusion: This study evaluated the association between BUN/Cr and the in-hospital mortality of cerebral infarction patients in ICU and found that BUN/Cr had weak correlation with the increased risk of in-hospital mortality of patients with cerebral infarction in ICU especially in males and those with respiratory failure, malignant cancer, and without liver disease, as well as those receiving anticoagulation.
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Neoplasias , Insuficiencia Respiratoria , Masculino , Humanos , Nitrógeno de la Urea Sanguínea , Creatinina , Enfermedad Crítica , Estudios de Cohortes , Bicarbonatos , Pronóstico , Infarto Cerebral , Glucosa , Anticoagulantes , Estudios RetrospectivosRESUMEN
Methyl vinyl ketone (MVK) is an environmental hazardous substrate which is mainly present in cigarette smoke, industrial waste, and exhaust gas. Despite many chances to be exposed to MVK, the cellular toxicity of MVK is largely unknown. Neurons are the main component of the brain, which is one the most vital organs to human beings. Nevertheless, the influence of MVK to neurons has not been investigated. Here, we determined whether MVK treatment negatively affects neuronal survival and axonal morphogenesis using primary hippocampal neuronal cultures. We treated hippocampal neurons with 0.1 µM to 3.0 µM MVK and observed a concentration-dependent increase of neuronal death rate. We also demonstrated that the treatment with a low concentration of MVK 0.1 µM or 0.3 µM inhibited axonal branching specifically without affecting axon outgrowth. Our results suggest that MVK is highly toxic to neurons.
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Butanonas , Emisiones de Vehículos , Butanonas/toxicidad , Supervivencia Celular , Humanos , MorfogénesisRESUMEN
OBJECTIVE: To observe the efficacy and complications of one-stage tumor resection to treat primary sacral neurogenic tumors and to discuss some details in the clinically relevant anatomy. METHODS: A retrospective analysis of 26 patients with neurogenic turors of the sacral spine who were surgically treated from January 2001 to January 2018, including 16 males and 10 females, aged from 21 to 69 years old with an average age of (39.3±10.9) years old. The courses of diseases ranged from 3 to 56 months with an average of (17.9±10.1) months. The diameters of presacral components ranged from 3.3 to 19.6 cm with an average of (8.7±4.1) cm. The proximal margin of presacral lesions was above the L5S1 level in 6 cases, and lower than L5S1 in 20 cases. A posterior incision approach for one-stage complete resection of the tumor was used firstly, and an anterior approach was combined when necessary. Spinal-pelvic reconstruction with the modified Galveston technique was also carried out in relevant cases. Whether to preserve the tumor-involved nerve roots depended on the situation during the operation. The operation time, intraoperative blood loss, pain relief, and complications were recorded. The lumbosacral spine stability and sacral plexus neurological function were evaluated during postoperative follow-up, and local recurrence and distant metastasis were examined as well. RESULTS: Total excision was achieved in all 26 patients, with an operation time of (160.4±35.3) mins and an intraoperative blood loss of (1 092.3±568.8) ml. Tumors have been removed via a posterior-only approach in 21 cases and via combined anterior/posterior approaches in 5 cases. The diameter of presacral masses components ranged from 11.3 to 19.6 cm with an average of (15.1±3.2) cm in patients with combined anterior/posterior approaches, and ranged from 3.3 to 10.9 cm with an average of (7.2±2.4) cm in patients with a posterior-only approach. Five of the six patients whose proximal margin of presacral masses was above the L5S1 level adopted combined anterior/posterior approaches, and 20 patients lower than the L5S1 level adopted the posterior-only approach. All the patients were followed up for 6 to 82 months with an average of(45.4±18.2)months. Postoperative lumbosacral pain and lower extremity radicular pain were significantly relieved, and sensation, muscle strength and bowel and bladder function were also improved to varying degrees. The postoperative early complications included superficial wound infection in 1 case and cerebrospinal fluid leakage in 2 cases. Pathology confirmed 17 cases of schwannoma, 7 cases of neurofibroma and 2 cases of malignant schwannoma. Local recurrence was observed in two cases of benign neurogenic tumors. One patient with a malignant nerve sheath tumor had lung metastasis, who died 20 months after the operation. In 17 cases of upper sacral neurogenic tumors, 4 cases did not undergo spinal-pelvic reconstruction with internal fixation, of which 2 cases suffered from postoperative segmental instability. Tumor-involved nerve roots were resected during surgery in 7 cases. One of these patients who had S2 and S3 nerve roots sacrificed simultaneously had an impaired bladder and bowel function postoperatively, and did not recover completely. In the other 6 cases, the neurological function was not damaged obviously or recovered well. CONCLUSION: The posterior approach can directly expose the lesions, and it is also convenient to deal with nerve roots and blood vessels. The operation time, intraoperative blood loss, degree of symptom relief, complication rate, and recurrence and metastasis rate can be controlled at an appropriate level. It is a safe and effective surgical approach. When the upper edge of the presacral mass is higher than the L5S1 level or the diameter of the presacral mass exceeds 10 cm, an additional anterior approach should be considered. The stress between the spine and pelvis is high, and internal fixation should be used to restore the mechanical continuity of the spine and pelvis during resection of neurogenic tumors of the high sacral spine. Most of the parent nerve roots have lost their function. Resection of a single parent nerve root is unlikely to cause severe neurological dysfunction, while the adjacent nerve roots have compensatory functions and should be preserved as much as possible during surgery.