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There are case reports of mouth ulcers caused by the coronavirus disease 2019 (COVID-19) messenger ribonucleic acid (mRNA) vaccine; however, the actual number and characteristics of cases are unknown. Therefore, we examined this issue using the Japanese Adverse Drug Event Report (JADER), a large Japanese database. We calculated the reported odds ratio (ROR) of drugs that may be specifically associated with mouth ulcers and assumed that a signal was present if the lower limit of the calculated ROR's 95% confidence interval (CI) was > 1. In addition, the time to symptom onset after administration of the COVID-19 mRNA and influenza HA vaccines was investigated. We found that the JADER database contained 4,661 mouth ulcer cases between April 2004 and March 2022. The COVID-19 mRNA vaccine was the eighth most common causative drug for mouth ulcers, with 204 reported cases. The ROR was 1.6 (95% CI, 1.4-1.9) and a signal was detected. There were 172 mouthulcer cases associated with the Pfizer-BioNTech's COVID-19 mRNA vaccine, 76.2% of which were female. The outcome was no unrecovered cases with the influenza HA vaccine, whereas the COVID-19 mRNA vaccine showed unrecovered cases (Pfizer-BioNTech: 12.2%, Moderna: 11.1%). The median time-to-onset of the mouth ulcers was two days for the COVID-19 mRNA vaccine and one day for the influenza HA vaccine, indicating that mouth ulcers caused by the COVID-19 mRNA vaccine were delayed adverse events. In this study, the COVID-19 mRNA vaccine was shown to cause mouth ulcers in a Japanese population.
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COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Vacinas contra Influenza , Influenza Humana , Úlceras Orais , Feminino , Humanos , Masculino , Preparações Farmacêuticas , Vacinas contra COVID-19/efeitos adversos , Úlceras Orais/induzido quimicamente , Úlceras Orais/epidemiologia , População do Leste Asiático , COVID-19/prevenção & controle , RNA Mensageiro/genética , Vacinas de mRNA , Sistemas de Notificação de Reações Adversas a MedicamentosRESUMO
Accurate assessment of renal function is essential for determining serum vancomycin (VCM) concentration. Creatinine clearance (Ccr)-calculated using the Cockcroft and Gault (CG) equation-can be used to evaluate renal function for determining VCM dosage. However, Ccr-based evaluation may not be an accurate representation of the renal function in the elderly. Herein, we examine the effectiveness of estimated glomerular filtration rate (eGFR) calculated using the Berlin Initiative Study-1 (BIS1) equation, for predicting the serum VCM concentration. Herein, we retrospectively analyzed patients (aged ≥ 75 years) who had received VCM. Serum VCM concentration was predicted based on Ccr and eGFR. eGFR was calculated using the Japanese equation for eGFR (eGFRJAP), Modification of Diet in Renal Disease (MDRD) equation (eGFRMDRD), chronic kidney disease epidemiology collaboration (CKD-EPI) equation (eGFRCKD-EPI), and BIS1 equation (eGFRBIS1). The predicted serum VCM concentration was compared with the measured values. Prediction bias, accuracy, and precision were evaluated by calculating the mean prediction error (ME), mean absolute prediction error (MAE), and root mean squared prediction error (RMSE). Our results showed that the ME between the measured and the predicted values calculated using Ccr and each eGFR was the largest and smallest when calculated based on Ccr and eGFRMDRD, respectively. MAE and RMSE were the largest and smallest when calculated based on Ccr and eGFRBIS1, respectively. A significant difference was observed in the MAE associated with eGFRJAP, eGFRMDRD, and eGFRCKD-EPI compared to that associated with eGFRBIS1. In conclusion, our results suggest that the BIS1 equation might be useful for determining the VCM dosage in the elderly.
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Insuficiência Renal Crônica , Vancomicina , Idoso , Creatinina , Taxa de Filtração Glomerular , Humanos , Pacientes , Estudos RetrospectivosRESUMO
Global multiconstituent concentration and emission fields obtained from the assimilation of the satellite retrievals of ozone, CO, NO2, HNO3, and SO2 from the Ozone Monitoring Instrument (OMI), Global Ozone Monitoring Experiment 2, Measurements of Pollution in the Troposphere, Microwave Limb Sounder, and Atmospheric Infrared Sounder (AIRS)/OMI are used to understand the processes controlling air pollution during the Korea-United States Air Quality (KORUS-AQ) campaign. Estimated emissions in South Korea were 0.42 Tg N for NO x and 1.1 Tg CO for CO, which were 40% and 83% higher, respectively, than the a priori bottom-up inventories, and increased mean ozone concentration by up to 7.5 ± 1.6 ppbv. The observed boundary layer ozone exceeded 90 ppbv over Seoul under stagnant phases, whereas it was approximately 60 ppbv during dynamical conditions given equivalent emissions. Chemical reanalysis showed that mean ozone concentration was persistently higher over Seoul (75.10 ± 7.6 ppbv) than the broader KORUS-AQ domain (70.5 ± 9.2 ppbv) at 700 hPa. Large bias reductions (>75%) in the free tropospheric OH show that multiple-species assimilation is critical for balanced tropospheric chemistry analysis and emissions. The assimilation performance was dependent on the particular phase. While the evaluation of data assimilation fields shows an improved agreement with aircraft measurements in ozone (to less than 5 ppbv biases), CO, NO2, SO2, PAN, and OH profiles, lower tropospheric ozone analysis error was largest at stagnant conditions, whereas the model errors were mostly removed by data assimilation under dynamic weather conditions. Assimilation of new AIRS/OMI ozone profiles allowed for additional error reductions, especially under dynamic weather conditions. Our results show the important balance of dynamics and emissions both on pollution and the chemical assimilation system performance.
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Materials with the pyrochlore/fluorite structure have diverse technological applications, from magnetism to nuclear waste disposal. Here we report the observation of structural instability present in the pyrochlores A2Zr2O6O' (A = Pr, La) and Yb2Ti2O6O', that exists despite ideal stoichiometry, ideal cation-ordering, the absence of lone pair effects, and a lack of magnetic order. Though these materials appear to have good long-range order, local structure probes find displacements, of the order of 0.01 nm, within the pyrochlore framework. The pattern of displacements of the A2O' sublattice mimics the entropically-driven fluxional motions characteristic of and well-known in the silica mineral ß-cristobalite. The universality of such displacements within the pyrochlore structure adds to the known structural diversity and explains the extreme sensitivity to composition found in quantum spin ices and the lack of ferroelectric behavior in pyrochlores.
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Aims: To compare the arrhythmic response to isoproterenol and exercise testing in newly diagnosed arrhythmogenic right ventricular cardiomyopathy (ARVC) patients. Methods and results: We studied isoproterenol [continuous infusion (45 µg/min) for 3 min] and exercise testing (workload increased by 30 W every 3 min) performed in consecutive newly diagnosed ARVC patients. Both tests were evaluated with regard to the incidence of (i) polymorphic premature ventricular contractions (PVCs) and couplet(s) or (ii) sustained or non-sustained ventricular tachycardia (VT) with left bundle branch block [excluding right ventricular outflow tract VT]; and compared to a control group referred for the evaluation of PVCs without structural heart disease. Thirty-seven ARVC patients (63.5% male, age 38 ± 16 years) were included. The maximal sinus rhythm heart rate achieved during isoproterenol testing was significantly lower compared to exercise testing (149 ± 17 bpm vs. 166 ± 19 bpm, P < 0.0001). However, the incidence of polymorphic ventricular arrhythmias was much higher during isoproterenol testing compared to exercise testing [33/37 (89.2%) vs. 16/37 (43.2%), P < 0.0001]. Interestingly, isoproterenol testing was arrhythmogenic in all 15 patients in whom baseline PVCs were reduced or suppressed during exercise testing. During both isoproterenol and exercise testing, control group presented a low incidence of ventricular arrhythmias compared to ARVC patients (8.1% vs. 89.2%, P < 0.0001 and 2.7% vs. 43.2%, P < 0.0001, respectively). Conclusions: The incidence of polymorphic ventricular arrhythmias is significantly higher during isoproterenol compared to exercise testing in newly diagnosed ARVC patients, suggesting its potential utility for the diagnosis.
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Agonistas Adrenérgicos beta/administração & dosagem , Displasia Arritmogênica Ventricular Direita/diagnóstico , Teste de Esforço , Ventrículos do Coração/fisiopatologia , Isoproterenol/administração & dosagem , Taquicardia Ventricular/etiologia , Complexos Ventriculares Prematuros/etiologia , Potenciais de Ação , Adulto , Displasia Arritmogênica Ventricular Direita/complicações , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Estudos de Casos e Controles , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/fisiopatologia , Adulto JovemRESUMO
We present the results of a combined ^{7}Li-NMR and diffraction study on LiGa_{0.95}In_{0.05}Cr_{4}O_{8}, a member of the LiGa_{1-x}In_{x}Cr_{4}O_{8} "breathing" pyrochlore family. Via specific heat and NMR measurements, we find that the complex sequence of first-order transitions observed for LiGaCr_{4}O_{8} is replaced by a single second-order transition at T_{f}=11 K. Neutron and x-ray diffraction rule out both structural symmetry lowering and magnetic long-range order as the origin of this transition. Instead, reverse Monte Carlo fitting of the magnetic diffuse scattering indicates that the low-temperature phase may be described as a collinear spin nematic state, characterized by a quadrupolar order parameter. This state also shows signs of short-range order between collinear spin arrangements on tetrahedra, revealed by mapping the reverse Monte Carlo spin configurations onto a three-state color model.
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OBJECTIVE: CCN family protein 2/connective tissue growth factor (CCN2/CTGF) promotes cartilage regeneration in experimental osteoarthritis (OA) models. However, CCN2 production is very low in articular cartilage. The aim of this study was to investigate whether or not CCN2 was promoted by cultured chondrocytes treated with low-intensity pulsed ultrasound (LIPUS) and to clarify its mechanism. METHODS: Human chondrocytic cell line (HCS)-2/8, rat primary epiphyseal and articular cartilage cells, and Ccn2-deficient chondrocytes that impaired chondrocyte differentiation, were treated with LIPUS for 20 min at 3.0 MHz frequency and 60 mW/cm2 power. Expressions of chondrocyte differentiation marker mRNAs were examined by real-time PCR (RT-PCR) analysis from HCS-2/8 cells and Ccn2-deficient chondrocytes at 30 min and 1 h after LIPUS treatment, respectively. CCN2 production was examined by Western blotting after 5 h of LIPUS treatment. Moreover, Ca2+ influx was measured by using a Fluo-4 probe. RESULTS: The gene expression of chondrocyte differentiation markers and CCN2 production were increased in cultured chondrocytes treated with LIPUS. In addition, Ca2+ influx and phosphorylation of p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK)1/2 were increased by LIPUS treatment, and the stability of TRPV4 and BKca channel mRNAs was decreased by siRNA against CCN2. Consistent with those findings, the LIPUS-induced the gene expressions of type II collagen (COL2a1) and Aggrecan (ACAN) observed in wild-type cells were not observed in the Ccn2-deficient chondrocytes. CONCLUSION: These data indicate that chondrocyte differentiation represented by CCN2 production was mediated via MAPK pathways activated by LIPUS-stimulated Ca2+ influx, which in turn was supported by the induced CCN2 molecules in articular chondrocytes.
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Condrócitos/efeitos da radiação , Fator de Crescimento do Tecido Conjuntivo/genética , Regulação da Expressão Gênica/efeitos da radiação , Terapia por Ultrassom/métodos , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Inativação Gênica , Humanos , Ratos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Valores de Referência , Sensibilidade e Especificidade , Ondas UltrassônicasRESUMO
We have synthesized high-quality single crystals of volborthite, a seemingly distorted kagome antiferromagnet, and carried out high-field magnetization measurements up to 74 T and ^{51}V NMR measurements up to 30 T. An extremely wide 1/3 magnetization plateau appears above 28 T and continues over 74 T at 1.4 K, which has not been observed in previous studies using polycrystalline samples. NMR spectra reveal an incommensurate order (most likely a spin-density wave order) below 22 T and a simple spin structure in the plateau phase. Moreover, a novel intermediate phase is found between 23 and 26 T, where the magnetization varies linearly with magnetic field and the NMR spectra indicate an inhomogeneous distribution of the internal magnetic field. This sequence of phases in volborthite bears a striking similarity to those of frustrated spin chains with a ferromagnetic nearest-neighbor coupling J_{1} competing with an antiferromagnetic next-nearest-neighbor coupling J_{2}.
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We report on the real space profile of spin polarons in the quasi-two-dimensional frustrated dimer spin system SrCu(2)(BO(3))(2) doped with 0.16% of Zn. The (11)B nuclear magnetic resonance spectrum exhibits 15 additional boron sites near nonmagnetic Zn impurities. With the help of exact diagonalizations of finite clusters, we have deduced from the boron spectrum, the distribution of local magnetizations at the Cu sites with fine spatial resolution, providing direct evidence for an extended spin polaron. The results are confronted with those of other experiments performed on doped and undoped samples of SrCu(2)(BO(3))(2).
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BACKGROUND AND OBJECTIVE: Tumor necrosis factor alpha (TNF-α) is a major cytokine implicated in various inflammatory diseases. The nature of the nuclear factors associated with human TNF-α gene regulation is not well elucidated. We previously identified a novel region located from -550 to -487 in human TNF-α promoter that did not contain the reported binding sites for nuclear factor kappa B (NF-κB) but showed lipopolysaccharide (LPS)-induced transcriptional activity. The purpose of this study is to identify novel factors that bind to the promoter region and regulate TNF-α expression. MATERIAL AND METHODS: To identify DNA-binding proteins that bound to the target region of TNF-α promoter, a cDNA library from LPS-stimulated human monocytic cell line THP-1 was screened using a yeast one-hybrid system. Cellular localizations of the DNA-binding protein in the cells were examined by subcellular immunocytochemistry. Nuclear amounts of the protein in LPS-stimulated THP-1 cells were identified by western blot analysis. Expression of mRNA of the protein in the cells was quantified by real-time polymerase chain reaction. Electrophoretic mobility shift assays were performed to confirm the DNA-binding profile. Overexpression of the protein and knockdown of the gene were also performed to investigate the role for TNF-α expression. RESULTS: Several candidates were identified from the cDNA library and transactivation-responsive DNA-binding protein 43 (TARDBP43; TDP-43) was focused on. Western blot analysis revealed that nuclear TDP-43 protein was increased in the LPS-stimulated THP-1 cells. Expression of TDP-43 mRNA was already enhanced before TNF-α induction by LPS. Electrophoretic mobility shift assay analysis showed that nuclear extracts obtained by overexpressing FLAG-tagged TDP-43 bound to the -550 to -487 TNF-α promoter fragments. Overexpression of TDP-43 in THP-1 cells resulted in an increase of TNF-α expression. Knockdown of TDP-43 in THP-1 cells downregulated TNF-α expression. CONCLUSION: We identified TDP-43 as one of the novel TNF-α factors and found that it bound to the LPS-responsive element in the TNF-α promoter to increase TNF-α expression.
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Proteínas de Ligação a DNA/genética , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Linhagem Celular , Proteínas de Ligação a DNA/análise , Regulação da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Plasmídeos/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/genética , Transcrição Gênica/genética , Ativação Transcricional/genética , Transfecção , Fator de Necrose Tumoral alfa/efeitos dos fármacosRESUMO
The hydroxyl radical (OH) is a key oxidant involved in the removal of air pollutants and greenhouse gases from the atmosphere. The ratio of Northern Hemispheric to Southern Hemispheric (NH/SH) OH concentration is important for our understanding of emission estimates of atmospheric species such as nitrogen oxides and methane. It remains poorly constrained, however, with a range of estimates from 0.85 to 1.4 (refs 4, 7-10). Here we determine the NH/SH ratio of OH with the help of methyl chloroform data (a proxy for OH concentrations) and an atmospheric transport model that accurately describes interhemispheric transport and modelled emissions. We find that for the years 2004-2011 the model predicts an annual mean NH-SH gradient of methyl chloroform that is a tight linear function of the modelled NH/SH ratio in annual mean OH. We estimate a NH/SH OH ratio of 0.97 ± 0.12 during this time period by optimizing global total emissions and mean OH abundance to fit methyl chloroform data from two surface-measurement networks and aircraft campaigns. Our findings suggest that top-down emission estimates of reactive species such as nitrogen oxides in key emitting countries in the NH that are based on a NH/SH OH ratio larger than 1 may be overestimated.
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Atmosfera/química , Radical Hidroxila/química , Modelos Teóricos , Poluentes Atmosféricos/química , Clorofórmio/química , Simulação por Computador , Óxidos de Nitrogênio/químicaRESUMO
In this report, chairs of the 7th International Workshop on the CCN family of Genes, review the progress made in understanding the biological functions of CCN proteins (CCN1, CCN2, CCN3, CCN4, CCN5 and CCN6) with a particular focus on their implications in various pathological conditions, including cancer, fibrosis, diabetes, and cardiovascular diseases.
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Carbon monoxide (CO) is of great interest as a restriction factor for pollutants related to incomplete combustions. This study attempted to evaluate CO emission in East China using the analytical Bayesian inverse method and observations at Mount Hua in springtime. The mixing ratio of CO at the receptor was calculated using 5-day source-receptor relationship (SRR) simulated by a Lagrangian Particle Dispersion Model (FLEXPART) and CO emission flux. The stability of the inversion solution was evaluated on the basis of repeated random sampling simulations. The inversion results demonstrated that there were two city cluster regions (the Beijing-Tianjin-Hebei region and the low reaches of the Yangtze River Delta) where the difference between a priori (Intercontinental Chemical Transport Experiment-Phase B, INTEX-B) and a posteriori was statistically significant and the a priori might underestimate the CO emission flux by 37 %. A correction factor (a posteriori/a priori) of 1.26 was suggested for CO emission in China in spring. The spatial distribution and magnitude of the CO emission flux were comparable to the latest regional emission inventory in Asia (REAS2.0). Nevertheless, further evaluation is still necessary in view of the larger uncertainties for both the analytical inversion and the bottom-up statistical approaches.
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Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Modelos Teóricos , Altitude , Teorema de Bayes , China , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Estações do AnoRESUMO
We report on NMR and torque measurements on the frustrated quasi-two-dimensional spin-dimer system SrCu(2)(BO(3))(2) in magnetic fields up to 34 T that reveal a sequence of magnetization plateaus at 1/8, 2/15, 1/6, and 1/4 of the saturation and two incommensurate phases below and above the 1/6 plateau. The magnetic structures determined by NMR involve a stripe order of triplets in all plateaus, suggesting that the incommensurate phases originate from proliferation of domain walls. We propose that the magnetization process of SrCu(2)(BO(3))(2) is best described as an incomplete devil's staircase.
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OBJECTIVE: Hypertrophy-like changes are often observed in chondrocytes during the development of osteoarthritis (OA). These changes play a crucial part in the OA-associated cartilage degradation and osteophyte formation. However, the pathogenesis leading to such changes is still unknown. In this study, we investigated the mechanism by which these hypertrophy-like changes are induced from the viewpoint of impaired glycolytic metabolism. METHODS: The effect of sodium fluoride (NaF) on glycolytic metabolism of cultured chondrocytes was confirmed by measurement of intracellular adenosine triphosphate (ATP) production. Translocation of phosphorylated Smad1/5/8 to the nucleus was evaluated by subcellular fractionation and Western blotting. Chondrocyte hypertrophy-like changes were investigated by real-time RT-PCR and Western blot analysis of differentiation markers. RESULTS: ATP production was dose-dependently decreased by NaF in the human chondrocytic cell line HCS-2/8. In addition, both chondrocyte proliferation and differentiation were inhibited, whereas cell death was promoted by treatment with NaF. Interestingly, combinational treatment with NaF and lactate enhanced translocation of phospho-Smad1/5/8 to the nucleus, as well as gene expression of ALP, VEGF, COL10a1, and matrix metalloproteinase13 (MMP13), which were the markers of late mature and hypertrophic chondrocytes. Furthermore, the production of type X collagen and activation of MMP9 were also promoted under the same conditions. CONCLUSIONS: These findings suggest that decreased ATP production by NaF promotes hypertrophy-like changes via activation of phospho-Smad1/5/8 in the presence of lactate. Novel metabolic aspects of OA pathogenesis are indicated herein.
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Condrócitos/metabolismo , Proteínas Smad Reguladas por Receptor/metabolismo , Trifosfato de Adenosina/biossíntese , Proteínas Morfogenéticas Ósseas/metabolismo , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Glicólise/efeitos dos fármacos , Glicólise/fisiologia , Humanos , Hipertrofia/induzido quimicamente , Hipertrofia/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/farmacologia , Lactato de Sódio/farmacologiaRESUMO
Fractionalization-the breaking up of an apparently indivisible microscopic degree of freedom-is one of the most counterintuitive phenomena in many-body physics. Here we study its most fundamental manifestation in spin ice, the only known fractionalized magnetic compound in 3D: we directly visualize the 1/r(2) magnetic Coulomb field of monopoles that emerge as the atomic magnetic dipoles fractionalize. We analyze the internal magnetic field distribution, relevant for local experimental probes. In particular, we present new zero-field NMR measurements that exhibit excellent agreement with the calculated line shapes, noting that this experimental technique can in principle measure directly the monopole density in spin ice. The distribution of field strengths is captured by a simple analytical form that exhibits a low density of low-field sites-in apparent disagreement with reported muon spin rotation results. Counterintuitively, the density of low-field locations decreases as the local ferromagnetic correlations imposed by the ice rules weaken.
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Cd2Os2O7 shows a peculiar metal-insulator transition at 227 K with magnetic ordering in a frustrated pyrochlore lattice, but its magnetic structure in the ordered state and the transition origin are yet uncovered. We observed a commensurate magnetic peak by resonant x-ray scattering in a high-quality single crystal. X-ray diffraction and Raman scattering experiments confirmed that the transition is not accompanied with any spatial symmetry breaking. We propose a noncollinear all-in-all-out spin arrangement on the tetrahedral network made of Os atoms. Based on this we suggest that the transition is not caused by the Slater mechanism as believed earlier but by an alternative mechanism related to the formation of the specific tetrahedral magnetic order on the pyrochlore lattice in the presence of strong spin-orbit interactions.
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Orexins are neuropeptides produced in the lateral hypothalamus and implicated in regulation of sleep-wake cycle. Selective loss of orexin neurons is found in the brain of patients with narcolepsy, but the mechanisms of this pathological change are unclear. A previous study showed that excessive stimulation of N-methyl-d-aspartate (NMDA) receptors by quinolinic acid (QA) caused selective loss of orexin neurons in rat hypothalamic slice culture. Here we examined QA toxicity on orexin neurons and melanin-concentrating hormone (MCH) neurons in vivo. Contrary to the expectation, injection of QA (60 and 120 nmol) into the lateral hypothalamus of male C57BL/6 mice caused selective loss of MCH neurons rather than orexin neurons, and this toxicity of QA was attenuated by MK-801, an NMDA receptor antagonist. Selective loss of MCH neurons with preserved orexin neurons was observed even when GABA(A) receptor antagonists such as bicuculline and picrotoxin were injected with QA. A significant decrease in the number of orexin neurons was induced when QA injection was performed in the dark phase of diurnal cycle, but the degree of the decrease was still lower than that in the number of MCH neurons. Finally, QA (60 nmol) induced selective loss of MCH neurons also in young rats at 3-4 weeks of age. These results do not support the hypothesis that acute excitotoxicity mediated by NMDA receptors is responsible for the pathogenesis of narcolepsy.
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Hormônios Hipotalâmicos/metabolismo , Hipotálamo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Melaninas/metabolismo , Melanóforos/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Hormônios Hipofisários/metabolismo , Ácido Quinolínico/toxicidade , Fatores Etários , Animais , Contagem de Células/métodos , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Hormônios Hipotalâmicos/antagonistas & inibidores , Hipotálamo/efeitos dos fármacos , Hipotálamo/patologia , Masculino , Melaninas/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/patologia , Orexinas , Hormônios Hipofisários/antagonistas & inibidores , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
Since fibrosis is observed in smokers' gingiva, it was hypothesized that fibrosis was caused by nicotine in the periodontium. Therefore, in this study, we investigated the effects of nicotine on the induction of a profibrotic molecule, connective tissue growth factor (CCN2/CTGF), in human gingival fibroblasts (HGFs) and periodontal ligament (PDL) cells. With 1 microg/mL nicotine, vacuolization and attenuated proliferation were observed. Interestingly, 1 microg/mL nicotine increased the production of CCN2/CTGF protein in both cells without increasing mRNA expression. Furthermore, type I collagen mRNA and protein were also increased and were significantly blocked by a CCN2/CTGF neutralizing antibody. This is the first report to describe a relationship between nicotine and CCN2/CTGF in periodontal tissue cells. Analysis of our data also indicated that nicotine was cytotoxic, while it increased CCN2/CTGF and, eventually, type I collagen production. These findings suggest that periodontal fibrosis can be promoted by nicotine from smoking via effects on CCN2/CTGF.
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Fator de Crescimento do Tecido Conjuntivo/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Ligamento Periodontal/efeitos dos fármacos , Adulto , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Relação Dose-Resposta a Droga , Feminino , Fibroblastos/metabolismo , Fibrose/induzido quimicamente , Regulação da Expressão Gênica/efeitos dos fármacos , Gengiva/citologia , Gengiva/efeitos dos fármacos , Gengiva/metabolismo , Humanos , Masculino , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , RNA Mensageiro/análise , Valores de Referência , Fumar/efeitos adversos , Fatores de Tempo , Adulto JovemRESUMO
We report a (51)V-NMR study on a high-quality powder sample of volborthite Cu3V2O7(OH)2 . 2H2O, a spin-1/2 Heisenberg antiferromagnet on a distorted kagome lattice formed by isosceles triangles. In the magnetic fields below 4.5 T, a sharp peak in the nuclear spin-lattice relaxation rate 1/T(1) accompanied with line broadening revealed a magnetic transition near 1 K. The low temperature phase shows anomalies such as a Lorentzian line shape, a 1/T(1) proportional, variantT behavior indicating dense low-energy excitations, and a large spin-echo decay rate 1/T(2) pointing to unusually slow fluctuations. Another magnetic phase appears above 4.5 T with less anomalous spectral shape and dynamics.