RESUMEN
Endotoxin tolerance (ET) is the hyporesponsiveness to lipopolysaccharide (LPS) after prior exposure. It is characterized by the downregulation of pro-inflammatory cytokine levels. Although ET protects against inflammation, its abolishment or recovery is critical for immunity. Nitric oxide (NO) plays various roles in the development of ET; however, its specific role in ET recovery remains unknown. To induce ET, RAW264.7 cells (a murine macrophage cell line) were pre-exposed to LPS (LPS1, 100 ng/mL for 24 h) and subsequently re-stimulated with LPS (LPS2, 100 ng/mL for 24 h). Expression of cytokines, NO, nitrite and inducible NO synthase (iNOS) were measured after 0, 12, 24, and 36 h of resting after LPS1 treatment with or without the iNOS-specific inhibitor, 1400W. LPS2-induced tumor necrosis factor-⺠(TNF-âº) and interleukin-6 (IL-6) were downregulated after LPS1 treatment, confirming the development of ET. Notably, TNF-⺠and IL-6 levels spontaneously rebounded after 12-24 h of resting following LPS1 treatment. In contrast, levles of NO, nitrite and iNOS increased during ET development and decreased during ET recovery. Moreover, 1400W inhibited ET development and blocked the early production of NO (<12 h) during ET recovery. Our findings suggest a negative correlation between iNOS-induced NO and cytokine levels in the abolishment of ET.
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Lipopolisacáridos , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico , Factor de Necrosis Tumoral alfa , Animales , Óxido Nítrico/metabolismo , Ratones , Lipopolisacáridos/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Células RAW 264.7 , Interleucina-6/metabolismo , Endotoxinas/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismoRESUMEN
AIM(S): To investigate the factorial structure, test-retest reliability, and internal consistency of the Older Volunteer Competency Scale and establish its psychometric properties. DESIGN: Cross-sectional survey. METHODS: A total of 1,000 older volunteers were recruited through random sampling and asked to complete the Older Volunteer Competency Scale. Subsequently, 100 participants were selected to participate in a second test to determine the scale's test-retest reliability. Factorial structure was assessed through exploratory factor analysis and confirmatory factor analysis, and internal consistency was assessed using Cronbach's α. RESULTS: Favorable exploratory and confirmatory factor analysis results were obtained. In addition, the three dimensions of the Older Volunteer Competency Scale, namely service awareness, service skills, and interpersonal interaction, had high internal consistency and test-retest reliability. CONCLUSION: The Older Volunteer Competency Scale is an effective and reliable research instrument for evaluating competency and needs among older volunteers.
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Proyectos de Investigación , Humanos , Encuestas y Cuestionarios , Estudios Transversales , Psicometría/métodos , Reproducibilidad de los ResultadosRESUMEN
The present survey research investigated older people's volunteering competency relating to social inequality by exploring the latent ability profile and demographic correlates of 1,000 older volunteers in 73 community care centersin southern Taiwan. Older volunteers were classified into advanced (n = 509), basic (n = 214), and novice (n = 277) groups. Demographics examined included: individualistic characteristics (religious beliefs), resources (education; number of chronic diseases), andsocial factors (serving area and spoken language, volunteering duration, marital status, and gender). Apparent inequality issues were revealed. The advanced group was better educated, Mandarin-speaking, and in urban areas. while the novice group featured the opposite (lower education Taiwanese-speaking suburban areas).
RESUMEN
Highly emissive semiconductor nanocrystals, or so-called quantum dots (QDs) possess a variety of applications from displays and biology labeling, to quantum communication and modern security. Though ensembles of QDs have already shown very high photoluminescent quantum yields (PLQYs) and have been widely utilized in current optoelectronic products, QDs that exhibit high absorption cross-section, high emission intensity, and, most important, nonblinking behavior at single-dot level have long been desired and not yet realized at room temperature. In this work, infrared-emissive MAPbI3 -based halide perovskite QDs is demonstrated. These QDs not only show a ≈100% PLQY at the ensemble level but also, surprisingly, at the single-dot level, display an extra-large absorption cross-section up to 1.80 × 10-12 cm2 and non-blinking single photon emission with a high single photon purity of 95.3%, a unique property that is extremely rare among all types of quantum emitters operated at room temperature. An in-depth analysis indicates that neither trion formation nor band-edge carrier trapping is observed in MAPbI3 QDs, resulting in the suppression of intensity blinking and lifetime blinking. Fluence-dependent transient absorption measurements reveal that the coexistence of non-blinking behavior and high single photon purity in these perovskite QDs results from a significant repulsive exciton-exciton interaction, which suppresses the formation of biexciton, and thus greatly reduces photocharging. The robustness of these QDs is confirmed by their excellent stability under continuous 1 h electron irradiation in high-resolution transmission electron microscope inspection. It is believed that these results mark an important milestone in realizing nonblinking single photon emission in semiconductor QDs.
RESUMEN
A polyphasic taxonomic approach was used to characterize a novel bacterium, designated strain CC-YST667T, isolated from poultry manure sampled in Taiwan. The cells were observed to be aerobic, motile and non-spore-forming rods, displaying positive reactions for oxidase. Optimal growth of CC-YST667T was observed at 25â°C, pH 8.0 and with 1â% (w/v) NaCl. The polar lipid profile consisted of phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and multiple unidentified polar lipids. The major polyamine was spermidine. The major cellular fatty acids (>5â%) included C16â:â0, C17â:â0cyclo, C19â:â0cyclo ω8c and C14â:â0 3OH/iso-C16â:â1 I. On the basis of the results of analysis of 16S rRNA gene sequences, this isolate showed the closest phylogenetic relationship with 'Neopusillimonas minor' (with 98.2â% similarity) and Paralcaligenes ureilyticus (with 97.3â% similarity) of the family Alcaligenaceae. The draft genome, (3.3 Mb) with a DNA G+C content of 57.2 mol%, harboured various genes involved in the biodegradation of aromatic hydrocarbons. CC-YST667T shared highest orthologous average nucleotide identity (OrthoANI) with the type strains of species of of the genera Neopusillimonas (72.4â77.9â%, n=2), Pusillimonas (72.8â73.0â%, n=2) and Pollutimonas (71.7â73.0â%, n=5). On the basis of its distinct phylogenetic, phenotypic and chemotaxonomic traits together with the results of comparative 16S rRNA gene sequencing, OrthoANI, digital DNA-DNA hybridization (DDH) and the phylogenomic placement, strain CC-YST667T is considered to represent a novel species of the genus Neopusillimonas, for which the name Neopusillimonas aromaticivorans sp. nov. is proposed. The type strain is CC-YST667T (=BCRC 81321T =JCM 34761T).
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Ácidos Grasos , Fosfolípidos , Animales , Ácidos Grasos/química , Fosfolípidos/química , Estiércol , Filogenia , ARN Ribosómico 16S/genética , Aves de Corral , Análisis de Secuencia de ADN , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genéticaRESUMEN
We attempted to examine the alterations elicited by opioids via coexpressed µ-opioid (MOP) and nociceptin/orphanin FQ (NOP) receptors for receptor localization and Erk1/2 (p44/42 MAPK) in human embryonic kidney (HEK) 293 cells. Through two-photon microscopy, the proximity of MOP and NOP receptors was verified by fluorescence resonance energy transfer (FRET), and morphine but not buprenorphine facilitated the process of MOP-NOP heterodimerization. Single-particle tracking (SPT) further revealed that morphine or buprenorphine hindered the movement of the MOP-NOP heterodimers. After exposure to morphine or buprenorphine, receptor localization on lipid rafts was detected by immunocytochemistry, and phosphorylation of Erk1/2 was determined by immunoblotting in HEK 293 cells expressing MOP, NOP, or MOP+NOP receptors. Colocalization of MOP and NOP on lipid rafts was enhanced by morphine but not buprenorphine. Morphine stimulated the phosphorylation of Erk1/2 with a similar potency in HEK 293 cells expressing MOP and MOP+NOP receptors, but buprenorphine appeared to activate Erk1/2 solely through NOP receptors. Our results suggest that opioids can fine-tune the cellular localization of opioid receptors and phosphorylation of Erk1/2 in MOP+NOP-expressing cells.
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Buprenorfina , Receptores Opioides , Humanos , Receptores Opioides/metabolismo , Receptor de Nociceptina , Analgésicos Opioides/farmacología , Células HEK293 , Fosforilación , Receptores Opioides mu/metabolismo , Buprenorfina/farmacología , Morfina/farmacologíaRESUMEN
Inhibiting the excessive release of glutamate in the brain is emerging as a promising therapeutic option and is efficient for treating neurodegenerative disorders. The aim of this study is to investigate the effect and mechanism of plantainoside D (PD), a phenylenthanoid glycoside isolated from Plantago asiatica L., on glutamate release in rat cerebral cortical nerve terminals (synaptosomes). We observed that PD inhibited the potassium channel blocker 4-aminopyridine (4-AP)-evoked release of glutamate and elevated concentration of cytosolic Ca2+. Using bafilomycin A1 to block glutamate uptake into synaptic vesicles and EDTA to chelate extracellular Ca2+, the inhibitory effect of PD on 4-AP-evoked glutamate release was prevented. In contrast, the action of PD on the 4-AP-evoked release of glutamate in the presence of dl-TBOA, a potent nontransportable inhibitor of glutamate transporters, was unaffected. PD does not alter the 4-AP-mediated depolarization of the synaptosomal membrane potential, suggesting that the inhibitory effect of PD on glutamate release is associated with voltage-dependent Ca2+ channels (VDCCs) but not the modulation of plasma membrane potential. Pretreatment with the Ca2+ channel blocker (N-type) ω-conotoxin GVIA abolished the inhibitory effect of PD on the evoked glutamate release, as did pretreatment with the protein kinase C inhibitor GF109203x. However, the PD-mediated inhibition of glutamate release was eliminated by applying the mitochondrial Na+/Ca2+ exchanger inhibitor CGP37157 or dantrolene, which inhibits Ca2+ release through ryanodine receptor channels. These data suggest that PD mediates the inhibition of evoked glutamate release from synaptosomes primarily by reducing the influx of Ca2+ through N-type Ca2+ channels, subsequently reducing the protein kinase C cascade.
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4-Aminopiridina , Ácido Glutámico , Ratas , Animales , Ácido Glutámico/metabolismo , Ratas Sprague-Dawley , 4-Aminopiridina/farmacología , Sinaptosomas/metabolismo , Señalización del Calcio , Proteína Quinasa C/metabolismo , Corteza Cerebral/metabolismo , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacologíaRESUMEN
Dysregulation of DNA damage response/repair and genomic instability promote tumorigenesis and the development of various neurological diseases. Autophagy is a dynamic catabolic process used for removing unnecessary or dysfunctional proteins and organelles in cells. Despite the consensus in the field that upregulation of autophagy promotes the initiation of the DNA damage response and assists the process of homologous recombination upon genotoxic stress, a few studies showed that upregulation of autophagy (or excessive autophagy), under certain circumstances, triggers caspase/apoptosis-independent DNA damage and promotes genomic instability in cells. As the cytoprotective and the DNA repairing roles of autophagy have been discussed extensively in different reviews, here, we mainly focus on describing the latest studies which reported the "opposite" roles of autophagy (or excessive autophagy). We will discuss whether the "dark side" (i.e., the opposite/unconventional effect) of autophagy on the maintenance of DNA integrity and genomic stability really does exist in cells and if it does, will it be one of the yet-to-be-identified causes of cancer, in this review.
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Autofagia , Inestabilidad Genómica , Autofagia/genética , Carcinogénesis/metabolismo , Daño del ADN/genética , Reparación del ADN , Inestabilidad Genómica/genética , HumanosRESUMEN
Saline springs within the Illinois Basin result from the discharge of deep-seated evaporated seawater (brine) and likely contain diverse and complex microbial communities that are poorly understood. In this study, seven saline/mineral springs with different geochemical characteristics and salinity origins were investigated using geochemical and molecular microbiological analyses to reveal the composition of microbial communities inhabiting springs and their key controlling factors. The 16S rRNA sequencing results demonstrated that each spring harbours a unique microbial community influenced by its geochemical properties and subsurface conditions. The microbial communities in springs that originated from Cambrian/Ordovician strata, which are deep confined units that have limited recharge from overlying formations, share a greater similarity in community composition and have a higher species richness and more overlapped taxa than those that originated from shallower Pennsylvanian strata, which are subject to extensive regional surface and groundwater recharge. The microbial distribution along the spring flow paths at the surface indicates that 59.8%-94.2% of total sequences in sedimentary samples originated from spring water, highlighting the role of springs in influencing microbiota in the immediate terrestrial environment. The results indicate that the springs introduce microbiota with a high biodiversity into surface terrestrial or aquatic ecosystems, potentially affecting microbial reservoirs in downstream ecosystems.
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Agua Subterránea , Microbiota , ARN Ribosómico 16S/genética , Salinidad , Microbiota/genética , Agua Subterránea/microbiología , Agua de Mar/microbiologíaRESUMEN
ABSTRACT: Recurrent pelvic pressure injuries are common among paraplegic patients with spinal cord injury. Most of them experienced multiple surgical treatments because of recurrence. Based on the "spare part" concept, the double fillet flap is feasible when all other reconstructive procedures were exhausted. In this case report, we present the double fillet flap technique to manage recurrent extended pelvic pressure ulcers in a paraplegic spinal cord injury patient.
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Procedimientos de Cirugía Plástica , Úlcera por Presión , Traumatismos de la Médula Espinal , Humanos , Paraplejía/complicaciones , Úlcera por Presión/etiología , Úlcera por Presión/cirugía , Procedimientos de Cirugía Plástica/métodos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/cirugía , Colgajos Quirúrgicos/cirugíaRESUMEN
BACKGROUND: The most challenging complication associated with lower blepharoplasty is ectropion, and the traditional lateral canthopexy or canthoplasty procedure may carry the risk of eyelid malposition or subsequent chemosis. We propose lateral tarsoplasty with a detailed description of the techniques to treat and even prevent ectropion by not involving the medial or lateral canthal ligament so as to avoid complications. MATERIALS AND METHODS: Lower eyelid laxity was analyzed with the snap-back test and distraction test before surgery. Approximately 5 mm medial to the lateral canthus, lateral tarsoplasty is performed through a full-thickness pentagonal tarsal-conjunctival resection according to the "overlapping test" for an accurate measurement of the amount of the tarsus to be resected. Seventy-two eyelids that received either ectropion correction or prevention with lateral tarsoplasty over an 8-year period at a single institution were collected and analyzed for this retrospective review. RESULTS: Lateral tarsoplasty was performed in 39 patients with a mean age of 63.8 years. Thirteen patients with 20 eyelids presented for ectropion correction, in whom 5 to 10 mm of tarsus was resected, 6.0 mm in average. The other 26 patients with 52 eyelids presented for ectropion prevention, in whom 3 to 7 mm of tarsus was resected, 4.1 mm in average. Apart from temporary mild chemosis, all patients experienced highly satisfactory results without any ectropion or malposition of the involved lower eyelids after a follow-up of 8.1 months in average. CONCLUSIONS: For patients with moderate and severe laxity of lower eyelids, lateral tarsoplasty without involvement of the lateral canthal ligament proves to be an effective way to treat and prevent lower eyelid ectropion.
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Blefaroplastia , Ectropión , Procedimientos de Cirugía Plástica , Blefaroplastia/métodos , Ectropión/etiología , Ectropión/cirugía , Párpados/cirugía , Humanos , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
The inhibition of synaptic glutamate release to maintain glutamate homeostasis contributes to the alleviation of neuronal cell injury, and accumulating evidence suggests that natural products can repress glutamate levels and associated excitotoxicity. In this study, we investigated whether eupatilin, a constituent of Artemisia argyi, affected glutamate release in rat cortical nerve terminals (synaptosomes). Additionally, we evaluated the effect of eupatilin in an animal model of kainic acid (KA) excitotoxicity, particularly on the levels of glutamate and N-methyl-D-aspartate (NMDA) receptor subunits (GluN2A and GluN2B). We found that eupatilin decreased depolarization-evoked glutamate release from rat cortical synaptosomes and that this effect was accompanied by a reduction in cytosolic Ca2+ elevation, inhibition of P/Q-type Ca2+ channels, decreased synapsin I Ca2+-dependent phosphorylation and no detectable effect on the membrane potential. In a KA-induced glutamate excitotoxicity rat model, the administration of eupatilin before KA administration prevented neuronal cell degeneration, glutamate elevation, glutamate-generating enzyme glutaminase increase, excitatory amino acid transporter (EAAT) decrease, GluN2A protein decrease and GluN2B protein increase in the rat cortex. Taken together, the results suggest that eupatilin depresses glutamate exocytosis from cerebrocortical synaptosomes by decreasing P/Q-type Ca2+ channels and synapsin I phosphorylation and alleviates glutamate excitotoxicity caused by KA by preventing glutamatergic alterations in the rat cortex. Thus, this study suggests that eupatilin can be considered a potential therapeutic agent in the treatment of brain impairment associated with glutamate excitotoxicity.
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Artemisia , Síndromes de Neurotoxicidad , Ratas , Animales , Ácido Glutámico/metabolismo , Sinapsinas/metabolismo , Artemisia/metabolismo , 4-Aminopiridina/farmacología , Ratas Sprague-Dawley , Corteza Cerebral/metabolismo , Calcio/metabolismo , Sinaptosomas/metabolismo , Exocitosis , Ácido Kaínico/farmacología , Síndromes de Neurotoxicidad/metabolismoRESUMEN
The neurotransmitter glutamate plays an essential role in excitatory neurotransmission; however, excessive amounts of glutamate lead to excitotoxicity, which is the most common pathogenic feature of numerous brain disorders. This study aimed to investigate the role of butyl 2-[2-(2-fluorophenyl)acetamido]benzoate (HFP034), a synthesized anthranilate derivative, in the central glutamatergic system. We used rat cerebro-cortical synaptosomes to examine the effect of HFP034 on glutamate release. In addition, we used a rat model of kainic acid (KA)-induced glutamate excitotoxicity to evaluate the neuroprotective potential of HFP034. We showed that HFP034 inhibits 4-aminopyridine (4-AP)-induced glutamate release from synaptosomes, and this inhibition was absent in the absence of extracellular calcium. HFP034-mediated inhibition of glutamate release was associated with decreased 4-AP-evoked Ca2+ level elevation and had no effect on synaptosomal membrane potential. The inhibitory effect of HFP034 on evoked glutamate release was suppressed by blocking P/Q-type Ca2+ channels and protein kinase C (PKC). Furthermore, HFP034 inhibited the phosphorylation of PKC and its substrate, myristoylated alanine-rich C kinase substrate (MARCKS) in synaptosomes. We also observed that HFP034 pretreatment reduced neuronal death, glutamate concentration, glial activation, and the levels of endoplasmic reticulum stress-related proteins, calpains, glucose-regulated protein 78 (GRP 78), C/EBP homologous protein (CHOP), and caspase-12 in the hippocampus of KA-injected rats. We conclude that HFP034 is a neuroprotective agent that prevents glutamate excitotoxicity, and we suggest that this effect involves inhibition of presynaptic glutamate release through the suppression of P/Q-type Ca2+ channels and PKC/MARCKS pathways.
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Ácido Glutámico , Sinaptosomas , 4-Aminopiridina/farmacología , Animales , Calcio/metabolismo , Corteza Cerebral/metabolismo , Ácido Glutámico/metabolismo , Ácido Kaínico/farmacología , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Sinaptosomas/metabolismo , ortoaminobenzoatosRESUMEN
Excessive glutamate release is known to be involved in the pathogenesis of neurological diseases, and suppression of glutamate release from nerve terminals is considered to be a treatment strategy. In this study, we investigated whether isosaponarin, a flavone glycoside isolated from wasabi leaves, could affect glutamate release in rat cerebral cortex nerve terminals (synaptosomes). The release of glutamate was evoked by the K+ channel blocker 4-aminopyridine (4-AP) and measured by an online enzyme-coupled fluorimetric assay. Isosaponarin produced a concentration-dependent inhibition of 4-AP-evoked glutamate release with a half-maximum inhibition of release value of 22 µM. The inhibition caused by isosaponarin was prevented by eliminating extracellular Ca2+ or by using bafilomycin A1, an inhibitor of synaptic vesicle exocytosis. Isosaponarin decreased intrasynaptosomal rises in Ca2+ levels that were induced by 4-AP, without affecting the synaptosomal membrane potential. The isosaponarin-induced inhibition of glutamate release was significantly prevented in synaptosomes that were pretreated with a combination of the calcium channel blockers ω-conotoxin GVIA (N-type) and ω-agatoxin IVA (P/Q-types). The protein kinase C (PKC) pan-inhibitor GF109203X and the Ca2+-dependent PKC inhibitor Go6976 abolished the inhibition of glutamate release by isosaponarin, while the Ca2+-independent PKC inhibitor rottlerin did not show any effect. The results from immunoblotting assays also showed that isosaponarin lowered PKC, PKCα, synaptosomal-associated protein of 25 kDa (SNAP-25), and myristoylated alanine-rich C-kinase substrate (MARCKS) phosphorylation induced by 4-AP. In addition, FM1-43-labeled synaptic vesicles in synaptosomes showed that treatment with isosaponarin resulted in an attenuation of the 4-AP-induced decrease in fluorescence intensity that is consistent with glutamate release. Transmission electron microscopy of synaptosomes also provided evidence that isosaponarin altered the number of synaptic vesicles. These results indicate that isosaponarin suppresses the Ca2+-dependent PKC/SNAP-25 and MARCKS pathways in synaptosomes, causing a decrease in the number of available synaptic vesicles, which inhibits vesicular glutamate release from synaptosomes.
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Ácido Glutámico , Sinaptosomas , Animales , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Corteza Cerebral/metabolismo , Ácido Glutámico/metabolismo , Potenciales de la Membrana , Terminaciones Nerviosas/metabolismo , Ratas , Ratas Sprague-Dawley , Sinaptosomas/metabolismoRESUMEN
Current anti-seizure drugs fail to control approximately 30% of epilepsies. Therefore, there is a need to develop more effective anti-seizure drugs, and medicinal plants provide an attractive source for new compounds. This study aimed to evaluate the possible anti-seizure and neuroprotective effects of neferine, an alkaloid from the lotus seed embryos of Nelumbo nucifera, in a kainic acid (KA)-induced seizure rat model and its underlying mechanisms. Rats were intraperitoneally (i.p.) administrated neferine (10 and 50 mg/kg) 30 min before KA injection (15 mg/kg, i.p.). Neferine pretreatment increased seizure latency and reduced seizure scores, prevented glutamate elevation and neuronal loss, and increased presynaptic protein synaptophysin and postsynaptic density protein 95 expression in the hippocampi of rats with KA. Neferine pretreatment also decreased glial cell activation and proinflammatory cytokine (interleukin-1ß, interleukin-6, tumor necrosis factor-α) expression in the hippocampi of rats with KA. In addition, NOD-like receptor 3 (NLRP3) inflammasome, caspase-1, and interleukin-18 expression levels were decreased in the hippocampi of seizure rats pretreated with neferine. These results indicated that neferine reduced seizure severity, exerted neuroprotective effects, and ameliorated neuroinflammation in the hippocampi of KA-treated rats, possibly by inhibiting NLRP3 inflammasome activation and decreasing inflammatory cytokine secretion. Our findings highlight the potential of neferine as a therapeutic option in the treatment of epilepsy.
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Alcaloides , Antineoplásicos , Bencilisoquinolinas , Fármacos Neuroprotectores , Alcaloides/farmacología , Alcaloides/uso terapéutico , Animales , Bencilisoquinolinas/farmacología , Bencilisoquinolinas/uso terapéutico , Citocinas/metabolismo , Inflamasomas/metabolismo , Ácido Kaínico/efectos adversos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ratas , Semillas/metabolismo , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológicoRESUMEN
Excessive release of glutamate induces excitotoxicity and causes neuronal damage in several neurodegenerative diseases. Natural products have emerged as potential neuroprotective agents for preventing and treating neurological disorders. Dehydrocorydaline (DHC), an active alkaloid compound isolated from Corydalis yanhusuo, possesses neuroprotective capacity. The present study investigated the effect of DHC on glutamate release using a rat brain cortical synaptosome model. Our results indicate that DHC inhibited 4-aminopyridine (4-AP)-evoked glutamate release and elevated intrasynaptosomal calcium levels. The inhibitory effect of DHC on 4-AP-evoked glutamate release was prevented in the presence of the vesicular transporter inhibitor bafilomycin A1 and the N- and P/Q-type Ca2+ channel blocker ω-conotoxin MVIIC but not the intracellular inhibitor of Ca2+ release dantrolene or the mitochondrial Na+/Ca2+ exchanger inhibitor CGP37157. Moreover, the inhibitory effect of DHC on evoked glutamate release was prevented by the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) inhibitor PD98059. Western blotting data in synaptosomes also showed that DHC significantly decreased the level of ERK1/2 phosphorylation and synaptic vesicle-associated protein synapsin I, the main presynaptic target of ERK. Together, these results suggest that DHC inhibits presynaptic glutamate release from cerebrocortical synaptosomes by suppressing presynaptic voltage-dependent Ca2+ entry and the MAPK/ERK/synapsin I signaling pathway.
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Alcaloides/farmacología , Calcio/metabolismo , Corteza Cerebral/efectos de los fármacos , Corydalis/química , Ácido Glutámico/metabolismo , Tejido Nervioso/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/química , Corteza Cerebral/metabolismo , Masculino , Tejido Nervioso/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Idiopathic multicentric Castleman disease (iMCD) is characterized by the benign proliferation of lymphoid cells in multiple regions. However, the co-occurrence of epithelial malignancy and idiopathic multicentric Castleman disease (iMCD) is rarely reported. Herein, we present a case of iMCD mimicking lymph nodal metastasis of Marjolin's ulcer in the lower extremity. A 53-year-old male presented with an unhealed chronic ulcer on the left lower leg and foot accompanied by an enlarged mass in the left inguinal region. Intralesional biopsy was performed, and pathological examination showed squamous cell carcinoma (SCC). Imaged studies revealed left calcaneus bone invasion, and lymph nodal metastasis was suspected by the cancer TNM staging of T4N2M0 pre-operatively. The patient received below-knee amputation and lymph node dissection; intraoperative histological examination showed no lymphatic nodal malignancy and diagnosed the patient as having iMCD with lymphadenopathy. The patient recovered uneventfully and was referred to a hematologist for further treatment.
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Carcinoma de Células Escamosas , Enfermedad de Castleman , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/cirugía , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/cirugía , Humanos , Extremidad Inferior/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , ÚlceraRESUMEN
A thyroid storm is an extreme manifestation of thyrotoxicosis, and is life threatening without an early diagnosis. Pregnancy or childbirth may worsen maternal hyperthyroidism or induce the development of a thyroid storm. Gestational hypertension, a disorder defined as new-onset hypertension, develops after 20 weeks of gestation and shares symptoms with a thyroid storm. The diagnosis of a thyroid storm may be challenging in patients with gestational hypertension. To highlight the significance of early thyrotoxicosis-related gastrointestinal symptoms, we report a case of a 38-year-old woman with a twin pregnancy, who was diagnosed with gestational hypertension, and then developed a thyroid storm during the peripartum period. She complained of nausea and abdominal pain, followed by tachycardia, hypertension, and a disturbance of consciousness with desaturation. After emergency caesarean section, fever, diarrhea, and high-output heart failure, with pulmonary edema, were noted during the postoperative period in the intensive care unit. The diagnosis of a thyroid storm was confirmed using the Burch-Wartofsky point scale, which was 75 points. In this patient, the uncommon gastrointestinal symptoms, as initial manifestations of thyrotoxicosis, indicated the development of a thyroid storm. The distinguished presentation of thyrotoxicosis-induced cardiomyopathy and peripartum cardiomyopathy also helped in the differential diagnosis between a thyroid storm and gestational hypertension. Aggressive treatment for thyrotoxicosis should not be delayed because of a missed diagnosis.
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Cardiomiopatías , Hipertensión Inducida en el Embarazo , Crisis Tiroidea , Tirotoxicosis , Adulto , Cardiomiopatías/complicaciones , Cesárea/efectos adversos , Femenino , Humanos , Embarazo , Crisis Tiroidea/complicaciones , Crisis Tiroidea/diagnóstico , Tirotoxicosis/complicacionesRESUMEN
Glutamate is the major excitatory neurotransmitter in the brain and is involved in many brain functions. In this study, we investigated whether typhaneoside, a flavonoid from Typhae angustifolia pollen, affects endogenous glutamate release from rat cortical synaptosomes. Using a one-line enzyme-coupled fluorometric assay, glutamate release stimulated by the K+ channel blocker 4-aminopyridine was monitored to explore the possible underlying mechanisms. The vesicular transporter inhibitor bafilomycin A1 and chelation of extracellular Ca2+ ions with EGTA suppressed the effect of typhaneoside on the induced glutamate release. Nevertheless, the typhaneoside activity has not been affected by the glutamate transporter inhibitor dl-threo-beta-benzyloxyaspartate. The synaptosomal plasma membrane potential was assayed using a membrane potential-sensitive dye DiSC3(5), and cytosolic Ca2+ concentrations ([Ca2+]C) was monitored by a Ca2+ indicator Fura-2. Results showed that typhaneoside did not alter the synaptosomal membrane potential but lowered 4-aminopyridine-induced increases in [Ca2+]C. Furthermore, the Cav2.2 (N-type) channel blocker ω-conotoxin GVIA blocked Ca2+ entry and inhibited the effect of typhaneoside on 4-aminopyridine-induced glutamate release. However, the inhibitor of intracellular Ca2+ release dantrolene and the mitochondrial Na+/Ca2+ exchanger blocker 7-chloro-5-(2-chloropheny)-1,5-dihydro-4,1-benzothiazepin-2(3H)-one have no effect on the suppression of glutamate release mediated by typhaneoside. Moreover, inhibition of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) prevented the inhibitory effect of typhaneoside on induced glutamate release. Typhaneoside reduced 4-aminopyridine-induced phosphorylation of ERK1/2 and the major presynaptic ERK target synapsin I, which is a synaptic vesicle-associated protein. In conclusion, these findings suggest a role for typhaneoside in modulating glutamate release by suppressing voltage-dependent Ca2+ channel mediated presynaptic Ca2+ influx and the MAPK/ERK/synapsin I signaling cascade.
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Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo N/metabolismo , Corteza Cerebral/efectos de los fármacos , Ácido Glutámico/metabolismo , Glicósidos/farmacología , Animales , Corteza Cerebral/metabolismo , Masculino , Potenciales de la Membrana/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismoRESUMEN
INTRODUCTION: THP-1 cells, a human leukemia monocytic cell line, differentiated by phorbol myristate acetate (PMA) are widely used as surrogate of human macrophages. Differentiated THP-1 cells acquire macrophage-like characteristics including more adherence and altered cell function. Nitric oxide (NO), an intracellular messenger, is critical in regulating cell differentiation. Here we elucidated whether NO relates to PMA-induced monocyte-to-macrophage differentiation of THP-1 cells. The mutual regulation of calcium and NO was also investigated. MATERIAL & METHODS: THP-1 cells were incubated with PMA for 24 h, followed by assay of adherence, morphological change, migration or IL-1ß release. L-NG-Nitroarginine methyl ester (l-NAME, a nitric oxide synthase inhibitor) or BAPTA-AM (a calcium chelator) was added before PMA stimulation, and levels of calcium and NO were measured. Furthermore, a selective inhibitor of inducible nitric oxide synthase (iNOS) activity was employed to study the role of iNOS. RESULTS AND DISCUSSION: Effects of PMA on upregulation of adherence, lipopolysaccharide-triggered IL-1ß, and migration ability of THP-1 cells were consistent with NO concentrations. Both l-NAME and BAPTA-AM mitigated effects of PMA on THP-1 cells differentiation. BAPTA-AM decreased levels of NO, while l-NAME had no effect on calcium levels. Of note, inhibition of iNOS activity decreased PMA-triggered upregulation of NO. CONCLUSION: PMA induced differentiation of THP-1 cells partially in a NO-dependent manner. The calcium signaling may mediate PMA-triggered upregulation of NO.