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RATIONALE: Early neurological deterioration (END) within 72 h of stroke onset is associated with poor prognosis. Optimizing hydration might reduce the risk of END. AIMS: This study aimed to determine in acute ischemic stroke patients if enhanced hydration versus standard hydration reduced the incidence of major (primary) and minor (secondary) END, as well as whether it increased the incidence of early neurological improvement (secondary), at 72 h after admission. SAMPLE SIZE ESTIMATE: A total of 244 participants per arm. METHODS AND DESIGN: A prospective, double-blinded, multicenter, parallel-group, randomized controlled trial conducted at four hospitals from April 2014 to July 2020, with data analyzed in August 2020. The sample size estimated was 488 participants (244 per arm). Ischemic stroke patients with measurable neurological deficits of onset within 12 h of emergency department presentation and blood urea nitrogen/creatinine (BUN/Cr) ratio ⩾ 15 at point of admission were enrolled and randomized to 0.9% sodium chloride infusions of varying rates-enhanced hydration (20 mL/kg body weight, one-third given via bolus and remainder over 8 h) versus standard hydration (60 mL/h for 8 h), followed by maintenance infusion of 40-80 mL/h for the subsequent 64 h. The primary outcome measure was the incidence of major END at 72 h after admission, defined as an increase in National Institutes of Health Stroke Scale of ⩾ 4 points from baseline. RESULTS: Overall, 487 participants were randomized (median age 67 years; 287 females). At 72 h, 7 (2.9%) in the enhanced hydration arm and 5 (2.0%) in the standard hydration developed major END (p = 0.54). The incidence of minor END and early neurological improvement did not differ between treatment arms. CONCLUSION AND RELEVANCE: Enhanced hydration did not reduce END or improve short-term outcomes in acute ischemic stroke. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02099383, https://clinicaltrials.gov/study/NCT02099383).
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Objectives: Invasive fungal spondylodiscitis (IFSD) is rare and could be lethal in certain circumstances. The previous literature revealed limited data concerning its outcomes. This study aimed to establish a risk-scoring system to predict the one-year mortality rate of this disease. Methods: A total of 53 patients from a multi-centered database in Taiwan were included in this study. All the clinicopathological and laboratory data were retrospectively analyzed. Variables strongly related to one-year mortality were identified using a multivariate Cox proportional hazards model. A receiver operating characteristic (ROC) curve was used to express the performance of our IFSD scoring model. Results: Five strong predictors were included in the IFSD score: predisposing immunocompromised state, the initial presentation of either radiculopathy or myelopathy, initial laboratory findings of WBC > 12.0 or <0.4 103/µL, hemoglobin < 8 g/dL, and evidence of candidemia. One-year mortality rates for patients with IFSD scores of 0, 1, 2, 3, and 4 were 0%, 16.7%, 56.3%, 72.7%, and 100%, respectively. The area under the curve of the ROC curve was 0.823. Conclusions: We developed a practical scoring model with easily obtained demographic, clinical, and laboratory parameters to predict the probability of one-year mortality in patients with IFSD. However, more large-scale and international validations would be necessary before this scoring model is commonly used.
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The coronavirus disease 2019 has become a threat to global healthcare because of its rapid spread and evolution. In severe cases, the initial management of the disease is mainly supportive therapy and mechanical ventilation. Therefore, we investigated whether a modified emergency department workflow affects the efficacy will influence the efficacy and patient outcomes of traumatic brain injury (TBI) in Taiwan. This retrospective observational study used the Chang Gung Research Database in Taiwan from 7 hospitals in the Chang Gung Memorial Hospital System. Clinical index parameters and treatment efficiencies were analyzed between the locally transmitted period (January 20, 2020-June 7, 2020, period 2) and the community spread period (May 19, 2021-July 27, 2021, period 4) with the same interval of the pre-pandemic in 2019 as a reference period. During the locally transmitted period, only the time interval for patients who had to wait for a brain CT examination was, on average, 7.7 minutes shorter, which reached statistical significance. In addition, the number of TBI patients under 18 years of age decreased significantly during the community spread period. The "Door to the operating room (OR)," with polymerase chain reaction (PCR) testing, was on average 109.7 minutes slower than without the PCR testing in the reference period 2019. TBI treatment efficiency was delayed because of the PCR test. However, the surgical volume and functional outcome during these 2 periods were statistically insignificant compared to the pre-pandemic period because the spread of the virus was well controlled and hospital capacity was increased.
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Lesões Encefálicas Traumáticas , COVID-19 , Humanos , Adolescente , COVID-19/epidemiologia , Taiwan/epidemiologia , Pandemias , Lesões Encefálicas Traumáticas/epidemiologia , Lesões Encefálicas Traumáticas/terapia , Bases de Dados FactuaisRESUMO
The NMDA receptor hypofunction has been implicated in schizophrenia, memory impairment, and Alzheimer's disease. Modulating the abundance of D-serine, a co-agonist of the NMDA receptor, is a strategy to treat symptoms of the NMDA receptor hypofunction. In contrast to D-amino acid oxidase (DAAO) inhibitors, which aim at decreasing the loss of D-serine, this study tried to identify serine racemase (SRR) agonists, which boost the conversion of L-serine to D-serine. We used holo and apo structures of human SRR for the molecular docking against the National Cancer Institute (NCI) and ZINC compound databases and validated their efficacy by in vitro SRR activity assay. We identified NSC294149 (2-amino-3-(3-nitroimidazo[1,2-a]pyridin-2-yl)sulfanylpropanoic acid) as a potential SRR agonist and confirmed its amelioration of the hazard ratio of survival of the AD model of fruit fly (Drosophila melanogaster). These results suggest that the SRR agonist could be a drug design target against the NMDA receptor hypofunction symptoms.
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OBJECTIVE: Endoscopic lumbar discectomy has been an alternative for treating lumbar disc herniation. Evidence-based study for the benefit zone of full-endoscopic lumbar discectomy (FELD) is necessary. The study compared the complication risks between the FELD and open discectomy or microdiscectomy. METHODS: The literature search was from 4 online databases for randomized controlled trials (RCTs) and cohort studies. The meta-analysis of different study designs was conducted separately. Complication rates were considered primary outcomes, and the recurrence and revision rates were considered secondary outcomes. RESULTS: Six RCTs and thirteen cohort studies met the eligibility criteria. The meta-analysis was conducted separately. From the pooled RCT meta-analysis, the overall complication rates of FELD and open discectomy/microdiscectomy were 5.5% and 10.4%, respectively. The moderate-quality evidence suggested that FELD had a lower risk of overall complications (risk ratio [RR] = 0.55, 95% confidence interval [CI] = 0.31-0.98). There was no significant difference in specific complications and recurrence. The analysis of cohort studies revealed no significant difference in overall complications, but there was significant heterogeneity in the results. The risk of dural injury was significantly lower for FELD (RR = 0.46, 95% CI = 0.22-0.96). The pooled meta-analysis from cohort studies suggested a higher risk of transient dysesthesia (RR = 3.70, 95% CI = 1.54-8.89), residual fragment (RR = 5.29, 95% CI = 2.67-10.45), and revision surgeries (RR = 1.53, 95% CI = 1.12-2.08) for FELD. CONCLUSIONS: The current evidence showed a lower risk of overall complications for FELD. The quality of evidence was moderate to low, and the risk of bias from the primary literature should be concerned.
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Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Vértebras Lombares/cirurgia , Discotomia/efeitos adversos , Discotomia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Endoscopia/efeitos adversos , Endoscopia/métodos , Reoperação , Discotomia Percutânea/efeitos adversos , Discotomia Percutânea/métodos , Resultado do TratamentoRESUMO
Autogenous bone grafts are the gold standard for interbody fusion implant materials; however, they have several disadvantages. Tantalum (Ta) and titanium (Ti) are ideal materials for interbody cages because of their biocompatibility, particularly when they are incorporated into a three-dimensional (3D) porous structure. We conducted an in vitro investigation of the cell attachment and osteogenic markers of self-fabricated uniform porous Ti (20%, 40%, 60%, and 80%), nonporous Ti, and porous Ta cages (n = 6) in each group. Cell attachment, osteogenic markers, and alkaline phosphatase (ALP) were measured. An in vivo study was performed using a pig-posterior-instrumented anterior interbody fusion model to compare the porous Ti (60%), nonporous Ti, and porous Ta interbody cages in 12 pigs. Implant migration and subsidence, determined using plain radiographs, were recorded before surgery, immediately after surgery, and at 1, 3, and 6 months after surgery. Harvested implants were assessed for bone ingrowth and attachment. Relative to the 20% and 40% porous Ti cages, the 60% and 80% cages achieved superior cellular migration into cage pores. Among the cages, osteogenic marker and ALP activity levels were the highest in the 60% porous Ti cage, osteocalcin expression was the highest in the nonporous Ti cage, and the 60% porous Ti cage exhibited the lowest subsidence. In conclusion, the designed porous Ti cage is biocompatible and suitable for lumbar interbody fusion surgery and exhibits faster fusion with less subsidence compared with porous Ta and nonporous Ti cages.
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BACKGROUND: Radiofrequency thermocoagulation trigeminal rhizotomy (RT-TR) through the foramen ovale is a minimally invasive treatment for trigeminal neuralgia. Navigation of magnetic resonance imaging (MRI) and CT fusion imaging is a well-established method for cannulation of the Gasserian ganglion. In this study, we use the inline measurements from fusion image to analyze the anatomical parameters between the actual and simulation trajectories and compare the short- and intermediate-term outcomes according to determinable factors. METHODS: The study included thirty-six idiopathic neuralgia patients who had undergone RT-TR with MRI and CT fusion image as a primary modality or repeated procedures. RESULTS: Among thirty-six treated patients, the inline length of the trigeminal cistern was longer for the simulated trajectory (8.4 ± 2.4 versus 6.5 ± 2.8 mm; p < 0.05), and the predominant structure at risk extrapolated from the inline trajectory was the brainstem, which signified a more medially directed route, in contrast with the equal weighting of temporal lobe and brainstem for the actual trajectory. The preoperative visual analogue scale (VAS) was 9.3 ± 1.0, which decreased to 2.5 ± 2.6 and 2.9 ± 3.1 at first (mean, 3 months) and second (mean, 14 months) postoperative follow-up, respectively. The postoperative VAS scores at the two follow-ups were not statistically significant without a covariate analysis. After adjustment for covariate risk factors, the second follow-up sustained therapeutic benefit was evident in patients with no prior history of related treatment, an ablation temperature greater than 70 °C, and needle location within or adjacent to the trigeminal cistern. CONCLUSIONS: This preliminary study demonstrated that the needle location between cistern and ganglion also plays a significant role in better intermediate-term results.
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Forame Oval , Neuralgia do Trigêmeo , Eletrocoagulação/métodos , Forame Oval/cirurgia , Humanos , Rizotomia/efeitos adversos , Resultado do Tratamento , Gânglio Trigeminal/diagnóstico por imagem , Gânglio Trigeminal/cirurgia , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgiaRESUMO
Microplastics (MPs) pollution has become a serious environmental issue worldwide, but its potential effects on health remain unknown. The administration of polystyrene MPs (PS-MPs) to mice for eight weeks impaired learning and memory behavior. PS-MPs were detected in the brain especially in the hippocampus of these mice. Concurrently, the hippocampus had decreased levels of immediate-early genes, aberrantly enhanced synaptic glutamate AMPA receptors, and elevated neuroinflammation, all of which are critical for synaptic plasticity and memory. Interestingly, ablation of the vagus nerve, a modulator of the gut-brain axis, improved the memory function of PS-MPs mice. These results indicate that exposure to PS-MPs in mice alters the expression of neuronal activity-dependent genes and synaptic proteins, and increases neuroinflammation in the hippocampus, subsequently causing behavioral changes through the vagus nerve-dependent pathway. Our findings shed light on the adverse impacts of PS-MPs on the brain and hippocampal learning and memory.
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Microplásticos , Poliestirenos , Animais , Ácido Glutâmico , Hipocampo , Camundongos , Plásticos , Poliestirenos/toxicidadeRESUMO
BACKGROUND: Neurovascular compression (NVC) in patients with trigeminal neuralgia (TN) can be a factor of treatment outcome, especially in microvascular decompression and stereotactic radiosurgery. No such effect has been reported in percutaneous radiofrequency rhizotomy (RF). This study aims to investigate whether NVC affects the efficacy of RF in patients with TN. METHODS: We retrospectively reviewed patients with TN who received RF in our institution. Pretreatment magnetic resonance imaging was performed in every patient, and the presence of NVC was reviewed independently by two physicians. The patients were followed up at least for a year after the treatment. Pain severity was assessed with a numeric rating scale (NRS). RESULTS: Sixty-two patients were included in the study. All of the patients had single-sided lesions, and 35 patients had NVC. There were no significant differences between these two groups of patients in terms of gender distribution, age, and pretreatment pain severity. Comparable pain severity improvement was found at 1-year follow-up between these two groups (NRS 7.93 ± 0.492 without compression vs 7.57 ± 0.451 with compression, P = 0.600). No significant difference in posttreatment pain severity at 1 year was found between these two patient groups (NRS 1.37 ± 0.466 without compression vs 1.66 ± 0.458 with compression, P = 0.667). CONCLUSIONS: For patients with TN treated by RF, the presence or absence of NVC is not likely to affect the 1-year pain control rate.
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Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Humanos , Imageamento por Ressonância Magnética , Cirurgia de Descompressão Microvascular/métodos , Estudos Retrospectivos , Rizotomia , Resultado do Tratamento , Neuralgia do Trigêmeo/cirurgiaRESUMO
ABSTRACT: The unplanned return to the operating room rate is a quality metric for assessing hospital performance. This study aimed to evaluate the cause, incidence, and time interval of unplanned returns in index neurosurgical procedures within 30âdays of the initial surgery as an internal audit. We retrospectively analyzed neurosurgical procedures between January 2015, and December 2019, in a single regional hospital. The definition of an unplanned return to the operating room was a patient who underwent two operations within 30âdays when the second procedure was not planned, staged, or related to the natural course of the disease.A total of 4365 patients were identified in our analysis, of which 93 (2%) had an unplanned return to the operating room within 30âdays of their initial surgery during admission. The most common reason for an unplanned return to the operating room for a cranial procedure was hemorrhage, followed by hydrocephalus and subdural effusion, which accounted for 49.5%(46/93), 12%(11/93), and 5.4%(5/93) of cases, respectively. In spinal procedures, the most common cause of return was a residual disc, followed by surgical site infection, which accounted for 5.4%(5/93) and 4.3%(4/93) of cases, respectively. The overall median time interval for unplanned returns to the operating room was 3 days (interquartile range, 1-9).Lowering the rate of postoperative hemorrhage in cranial surgery and postoperative residual disc in spine surgery was crucial as an internal audit in a 5-year single institute follow-up. However, the unplanned reoperation rate is less helpful in benchmarking because of the heterogeneity of patients between hospitals.
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Doenças do Sistema Nervoso/cirurgia , Procedimentos Neurocirúrgicos , Melhoria de Qualidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/normas , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos , Adulto JovemRESUMO
Glioblastoma multiforme (GBM) is the most common malignant primary neoplasm of the adult central nervous system originating from glial cells. The prognosis of those affected by GBM has remained poor despite advances in surgery, chemotherapy, and radiotherapy. Photochemical internalization (PCI) is a release mechanism of endocytosed therapeutics into the cytoplasm, which relies on the membrane disruptive effect of light-activated photosensitizers. In this study, phototherapy by PCI was performed on a human GBM cell-line using the topoisomerase II inhibitor etoposide (Etop) and the photosensitizer protoporphyrin IX (PpIX) loaded in nanospheres (Ns) made from generation-5 polyamidoamine dendrimers (PAMAM(G5)). The resultant formulation, Etop/PpIX-PAMAM(G5) Ns, measured 217.4 ± 2.9 nm in diameter and 40.5 ± 1.3 mV in charge. Confocal microscopy demonstrated PpIX fluorescence within the endo-lysosomal compartment, and an almost twofold increase in cellular uptake compared to free PpIX by flow cytometry. Phototherapy with 3 min and 5 min light illumination resulted in a greater extent of synergism than with co-administered Etop and PpIX; notably, antagonism was observed without light illumination. Mechanistically, significant increases in oxidative stress and apoptosis were observed with Etop/PpIX-PAMAM(G5) Ns upon 5 min of light illumination in comparison to treatment with either of the agents alone. In conclusion, simultaneous delivery and endo-lysosomal co-localization of Etop and PpIX by PAMAM(G5) Ns leads to a synergistic effect by phototherapy; in addition, the finding of antagonism without light illumination can be advantageous in lowering the dark toxicity and improving photo-selectivity.
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Osteosarcoma, a common aggressive and malignant cancer, appears in the musculoskeletal system among young adults. The major cause of mortality in osteosarcoma was the recurrence of lung metastases. However, the molecular mechanisms of metastasis involved in osteosarcomas remain unclear. Recently, CXCL1 and CXCR2 have been crucial indicators for lung metastasis in osteosarcoma by paracrine releases, suggesting the involvement of directing neutrophils into tumor microenvironment. In this study, overexpression of CXCL1 has a positive correlation with the migratory and invasive activities in osteosarcoma cell lines. Furthermore, the signaling pathway, CXCR2/FAK/PI3K/Akt, is activated through CXCL1 by promoting vascular cell adhesion molecule 1 (VCAM-1) via upregulation of nuclear factor-kappa B (NF-κB) expression and nuclear translocation. The in vivo animal model further demonstrated that CXCL1 serves as a critical promoter in osteosarcoma metastasis to the lung. The correlated expression of CXCL1 and VCAM-1 was observed in the immunohistochemistry staining from human osteosarcoma specimens. Our findings demonstrate the cascade mechanism regulating the network in lung metastasis osteosarcoma, therefore indicating that the CXCL1/CXCR2 pathway is a worthwhile candidate to further develop treatment schemas.
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Gene transfection is a valuable tool for analyzing gene regulation and function, and providing an avenue for the genetic engineering of cells for therapeutic purposes. Though efficient, the potential concerns over viral vectors for gene transfection has led to research in non-viral alternatives. Cationic polyplexes such as those synthesized from chitosan offer distinct advantages such as enhanced polyplex stability, cellular uptake, endo-lysosomal escape, and release, but are limited by the poor solubility and viscosity of chitosan. In this study, the easily synthesized biocompatible and biodegradable polymeric polysorbate 80 polybutylcyanoacrylate nanoparticles (PS80 PBCA NP) are utilized as the backbone for surface modification with chitosan, in order to address the synthetic issues faced when using chitosan alone as a carrier. Plasmid DNA (pDNA) containing the brain-derived neurotrophic factor (BDNF) gene coupled to a hypoxia-responsive element and the cytomegalovirus promotor gene was selected as the genetic cargo for the in vitro transfection-guided neural-lineage specification of mouse induced pluripotent stem cells (iPSCs), which were assessed by immunofluorescence staining. The chitosan-coated PS80 PBCA NP/BDNF pDNA polyplex measured 163.8 ± 1.8 nm and zeta potential measured -34.8 ± 1.8 mV with 0.01% (w/v) high molecular weight chitosan (HMWC); the pDNA loading efficiency reached 90% at a nanoparticle to pDNA weight ratio of 15, which also corresponded to enhanced polyplex stability on the DNA stability assay. The HMWC-PS80 PBCA NP/BDNF pDNA polyplex was non-toxic to mouse iPSCs for up to 80 µg/mL (weight ratio = 40) and enhanced the expression of BDNF when compared with PS80 PBCA NP/BDNF pDNA polyplex. Evidence for neural-lineage specification of mouse iPSCs was observed by an increased expression of nestin, neurofilament heavy polypeptide, and beta III tubulin, and the effects appeared superior when transfection was performed with the chitosan-coated formulation. This study illustrates the versatility of the PS80 PBCA NP and that surface decoration with chitosan enabled this delivery platform to be used for the transfection-guided differentiation of mouse iPSCs.
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Fator Neurotrófico Derivado do Encéfalo/genética , Quitosana , Embucrilato , Células-Tronco Pluripotentes Induzidas/fisiologia , Nanopartículas/química , Transfecção/métodos , Animais , Diferenciação Celular , Camundongos , Neurônios , PlasmídeosRESUMO
BACKGROUND: We developed a porous Ti alloy/PEEK composite interbody cage by utilizing the advantages of polyetheretherketone (PEEK) and titanium alloy (Ti alloy) in combination with additive manufacturing technology. METHODS: Porous Ti alloy/PEEK composite cages were manufactured using various controlled porosities. Anterior intervertebral lumbar fusion and posterior augmentation were performed at three vertebral levels on 20 female pigs. Each level was randomly implanted with one of the five cages that were tested: a commercialized pure PEEK cage, a Ti alloy/PEEK composite cage with nonporous Ti alloy endplates, and three composite cages with porosities of 40, 60, and 80%, respectively. Micro-computed tomography (CT), backscattered-electron SEM (BSE-SEM), and histological analyses were performed. RESULTS: Micro-CT and histological analyses revealed improved bone growth in high-porosity groups. Micro-CT and BSE-SEM demonstrated that structures with high porosities, especially 60 and 80%, facilitated more bone formation inside the implant but not outside the implant. Histological analysis also showed that bone formation was higher in Ti alloy groups than in the PEEK group. CONCLUSION: The composite cage presents the biological advantages of Ti alloy porous endplates and the mechanical and radiographic advantages of the PEEK central core, which makes it suitable for use as a single implant for intervertebral fusion.
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Fusão Vertebral , Titânio , Animais , Benzofenonas , Desenvolvimento Ósseo , Feminino , Cetonas , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Polietilenoglicóis , Polímeros , Porosidade , Suínos , Microtomografia por Raio-XRESUMO
Myocardial infarction is the leading cause of morbidity and mortality worldwide. Although myocardial reperfusion after ischemia (I/R) is an effective method to save ischemic myocardium, it can cause adverse reactions, including increased oxidative stress and cardiomyocyte apoptosis. Mitochondrial fission and mitophagy are essential factors for mitochondrial quality control, but whether they play key roles in cardiac I/R injury remains unknown. New pharmacological or molecular interventions to alleviate reperfusion injury are currently considered desirable therapies. Vitamin D3 (Vit D3) regulates cardiovascular function, but its physiological role in I/R-exposed hearts, especially its effects on mitochondrial homeostasis, remains unclear. An in vitro hypoxia/reoxygenation (H/R) model was established in H9c2 cells to simulate myocardial I/R injury. H/R treatment significantly reduced H9c2 cell viability, increased apoptosis, and activated caspase 3. In addition, H/R treatment increased mitochondrial fission, as manifested by increased expression of phosphorylated dynein-related protein 1 (p-Drp1) and mitochondrial fission factor (Mff) as well as increased mitochondrial translocation of Drp1. Treatment with the mitochondrial reactive oxygen species scavenger MitoTEMPO increased cell viability and decreased mitochondrial fission. H/R conditions elicited excessive mitophagy, as indicated by increased expression of BCL2-interacting protein 3 (BNIP3) and light chain (LC3BII/I) and increased formation of autolysosomes. In contrast, Vit D3 reversed these effects. In a mouse model of I/R, apoptosis, mitochondrial fission, and mitophagy were induced. Vit D3 treatment mitigated apoptosis, mitochondrial fission, mitophagy, and myocardial ultrastructural abnormalities. The results indicate that Vit D3 exerts cardioprotective effects against I/R cardiac injury by protecting mitochondrial structural and functional integrity and reducing mitophagy.
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Spreading depolarization (SD) represents a neurological process characterized by a massive, self-sustaining wave of brain cell depolarization. Understanding its mechanism is important for treating ischemic or hemorrhagic stroke and migraine with aura. Many believed that ion fluxes through NMDA receptors (NMDARs) are responsible for neuronal transmembrane currents of SD. However, the explicit role of NMDARs remains ambiguous. This is in part due to the limitation of traditional pharmacological approaches in resolving the contribution of NMDARs in different intercellular and intracellular processes of SD. Here, we applied single-cell blockade and genetic deletion methods to remove functional NMDARs from individual hippocampal CA1 neurons in order to examine the role of NMDARs in the depolarization mechanism without affecting the propagation of SD. We analyzed neuronal membrane potential changes to demonstrate that NMDARs are not required for initiating the depolarization. Consistently, neuronal input resistance (RN) revealed a sharp decline at the start of SD, which was unaffected by blocking NMDARs. Instead, the recovery of both membrane potential and RN during the late phase of SD was facilitated by inhibition of NMDARs, indicating that NMDARs are responsible for sustaining the depolarization. Our results strongly indicate that NMDAR activation is not a determinant of the initiation of depolarization but is important for sustaining transmembrane ion fluxes during SD.
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Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Região CA1 Hipocampal/metabolismo , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos ICRRESUMO
High-grade gliomas (HGGs) are a rapidly progressive and highly recurrent group of primary brain tumors. Despite aggressive surgical resection with chemoradiotherapy, prognoses remained poor. Valproic acid (VPA), a histone deacetylase inhibitor has shown the potential to inhibit glioma cell growth in vitro through several diverse mechanisms. However clinical studies regarding the effect of VPA on HGGs are limited. This study aimed to investigate whether using VPA in patients with HGGs under temozolomide (TMZ) would lead to a better overall survival (OS).We used the Taiwan National Health Insurance Research database to conduct this population-based cohort study. A total of 2379 patients with HGGs under TMZ treatment were included and were further classified into VPA (nâ=â1212, VPA ≥ 84 defined daily dose [DDD]) and non-VPA (nâ=â1167, VPA < 84 DDD) groups. Each patient was followed from 1998 to 2013 or until death. A Cox proportional hazard regression was performed to evaluate the effect of VPA and OS.The VPA group had a longer mean OS time compared with the non-VPA group (OS: 50.3â±â41.0 vs 42.0â±â37.2 months, Pâ<â.001). In patients between 18 and 40 years old, the difference is most significant (OS: 70.5â±â48.7 vs 55.1â±â46.0, Pâ=â.001). The adjusted hazard ratio is 0.81 (95% confidence interval, 0.72-0.91) for the VPA group relative to the non-VPA group.VPA at over 84 DDD improved OS in HGGs TMZ treatment.
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Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Estadiamento de Neoplasias , Vigilância da População/métodos , Temozolomida/uso terapêutico , Ácido Valproico/uso terapêutico , Adolescente , Adulto , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Inibidores Enzimáticos/uso terapêutico , Feminino , Seguimentos , Glioma/diagnóstico , Glioma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Taiwan/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Rheumatoid arthritis (RA) has been associated with air pollution, possibly due to the augmentation of inflammatory effects. In this study, we aimed to determine the roles of inflammatory pathways and microRNA involved in the pathogenesis of RA fibroblast-like synoviocytes (FLS) inflammation induced by particulate matter. METHODS: The inflammatory mediators, messenger RNAs, microRNAs and their interrelationships were investigated using western blotting, QPCR, ELISA and immunohistochemistry. RESULTS: Particulate matter (PMs) induced an increase in the expression of interleukin-6 (IL-6) and cyclooxygenase-II (COX-II) in RA-FLS and microRNA-137 was found definitely to mediate the inflammatory pathways. PMs-induced generation of reactive oxygen species (ROS) in RA-FLS was attenuated by pretreatment with antioxidants. Nox-dependent ROS generation led to phosphorylation of ERK1/2, p38 and JNK, followed by downregulation of microRNA-137. In vivo studies, the joints of rats exposed to PMs revealed synovial fibroblast inflammation under pathologic examination and the expressions of IL-6 and COX-II were obviously increased. PMs exposure results in activated ROS-mediated mitogen-activated protein kinase (MAPK) signaling pathways and cause increased IL-6 and COX-II through downregulation of hsa-miRNA-137, which lead to inflammation and RA exacerbation. CONCLUSIONS: microRNA-137 plays an important role in PMs-induced RA acute exacerbation through MAPK signaling pathways and IL-6/COX-II activation. Targeting these mechanisms can potentially be used to develop new therapeutic strategies and prevention of RA inflammation in the future.