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1.
Eur Arch Paediatr Dent ; 23(6): 969-977, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36063356

RESUMO

PURPOSE: We have less understanding of which socioeconomic status (SES) indicators may be reflective of latent socioeconomic inequalities in toothbrushing behaviours, especially finishing-toothbrushing by parents in young children. The aim of this study was to reveal the socioeconomic inequalities in children's toothbrushing and finishing-toothbrushing by parents and if it varies by SES indicators. METHODS: We used data from 'Survey on Children's Life' conducted by A city of Okinawa Prefecture, Japan. The multiple imputed data of 902 (boys, 453) included self-reported children's toothbrushing behaviour and finishing-toothbrushing by parents in three-to six-year-old children. SES was assessed using self-reported household income and parental educational attainment. Absolute and relative inequalities in toothbrushing behaviours were quantified using the slope index of inequality (SII) and relative index of inequality (RII), respectively. RESULTS: There were significant absolute and relative inequalities of children's toothbrushing for household income (SII and RII were 0.241 and 2.73, respectively), of finishing-toothbrushing by parents for household income (SII and RII were 0.133 and 3.28, respectively), and educational attainment (SII and RII were 0.166 and 5.55, respectively). The same inequality trends were observed after adjusting for covariates (child's age and sex, family structure, breakfast and dinner frequency, and sleep duration). CONCLUSION: Socioeconomic inequalities in children's toothbrushing and finishing-toothbrushing by parents varied according to SES indicators.


Assuntos
Disparidades nos Níveis de Saúde , Escovação Dentária , Masculino , Criança , Humanos , Pré-Escolar , Japão/epidemiologia , Classe Social , Estilo de Vida , Fatores Socioeconômicos
2.
Cereb Cortex ; 29(5): 2183-2195, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30796817

RESUMO

The hippocampus is functionally heterogeneous between the dorsal and ventral subfields with left-right asymmetry. To determine the possible location of contextual memory, we performed an inhibitory avoidance task to analyze synaptic plasticity using slice patch-clamp technique. The training bilaterally increased the AMPA/NMDA ratio at dorsal CA3-CA1 synapses, whereas the training did not affect the ratio at ventral CA3-CA1 synapses regardless of the hemisphere. Moreover, sequential recording of miniature excitatory postsynaptic currents and miniature inhibitory postsynaptic currents from the same CA1 neuron clearly showed learning-induced synaptic plasticity. In dorsal CA1 neurons, the training dramatically strengthened both excitatory and inhibitory postsynaptic responses in both hemispheres, whereas the training did not promote the plasticity in either hemisphere in ventral CA1 neurons. Nonstationary fluctuation analysis further revealed that the training bilaterally increased the number of AMPA or GABAA receptor channels at dorsal CA1 synapses, but not at ventral CA1 synapses, suggesting functional heterogeneity of learning-induced receptor mobility. Finally, the performance clearly impaired by the bilateral microinjection of plasticity blockers in dorsal, but not ventral CA1 subfields, suggesting a crucial role for contextual learning. The quantification of synaptic diversity in specified CA1 subfields may help us to diagnose and evaluate cognitive disorders at the information level.


Assuntos
Região CA1 Hipocampal/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Plasticidade Neuronal , Células Piramidais/fisiologia , Animais , Aprendizagem da Esquiva , Região CA3 Hipocampal/fisiologia , Masculino , Potenciais Pós-Sinápticos em Miniatura , Vias Neurais/fisiologia , Ratos Sprague-Dawley , Receptores de AMPA/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia
3.
Nat Commun ; 9(1): 3110, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068947

RESUMO

The original version of this Article omitted the following from the Acknowledgements: 'J. Ma's primary affiliation is Shanghai Jiao Tong University.' This has been corrected in both the PDF and HTML versions of the Article.

4.
Nat Commun ; 9(1): 2666, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29991805

RESUMO

Magnetization plateaus in quantum magnets-where bosonic quasiparticles crystallize into emergent spin superlattices-are spectacular yet simple examples of collective quantum phenomena escaping classical description. While magnetization plateaus have been observed in a number of spin-1/2 antiferromagnets, the description of their magnetic excitations remains an open theoretical and experimental challenge. Here, we investigate the dynamical properties of the triangular-lattice spin-1/2 antiferromagnet Ba3CoSb2O9 in its one-third magnetization plateau phase using a combination of nonlinear spin-wave theory and neutron scattering measurements. The agreement between our theoretical treatment and the experimental data demonstrates that magnons behave semiclassically in the plateau in spite of the purely quantum origin of the underlying magnetic structure. This allows for a quantitative determination of Ba3CoSb2O9 exchange parameters. We discuss the implication of our results to the deviations from semiclassical behavior observed in zero-field spin dynamics of the same material and conclude they must have an intrinsic origin.

5.
Phys Rev E ; 96(1-1): 012145, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29347216

RESUMO

We study critical and magnetic properties of a bilayer Ising system consisting of two triangular planes A and B, with the antiferromagnetic (AF) coupling J_{A} and the ferromagnetic (FM) one J_{B} for the respective layers, which are coupled by the interlayer interaction J_{AB} by using Monte Carlo simulations. When J_{A} and J_{B} are of the same order, the unfrustrated FM plane orders first at a high temperature T_{c1}∼J_{B}. The spontaneous FM order then exerts influence on the other frustrated AF plane as an effective magnetic field, which subsequently induces a ferrimagnetic order in this plane at low temperatures below T_{c2}. When short-range order is developed in the AF plane while the influence of the FM plane is still small, there appears a preemptive Berezinskii-Kosterlitz-Thouless-type pseudocritical crossover regime just above the ferrimagnetic phase transition point, where the short-distance behavior up to a rather large length scale exponentially diverging in ∝J_{A}/T is controlled by a line of Gaussian fixed points at T=0. In the crossover region, a continuous variation in the effective critical exponent 4/9≲η^{eff}≲1/2 is observed. The phase diagram by changing the ratio J_{A}/J_{B} is also investigated.

6.
J Perinatol ; 36(12): 1101-1105, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27684416

RESUMO

OBJECTIVE: Cytomegalovirus (CMV) is the most common cause of congenital infection and can cause neurodevelopmental disabilities, although a majority of patients are asymptomatic. Biomarkers associated with disease severity would be desirable to distinguish asymptomatic from mildly symptomatic patients who may benefit from antiviral treatment. MicroRNAs (miRNAs) are noncoding RNAs that may have the potential to serve as biomarkers. STUDY DESIGN: Thirteen infants with congenital CMV infection were enrolled, and plasma levels of 11 human- and 3 CMV-encoded miRNAs were quantitated by real-time PCR. Plasma levels of miRNAs and their associations with clinical features were evaluated. RESULTS: The levels of miR-183-5p and miR-210-3p were significantly higher in patients with congenital CMV infection than in control infants, whereas no significant associations between levels of miRNAs and clinical features of congenital CMV infection were observed. CONCLUSION: Plasma miRNAs could be associated with the pathogenesis of congenital CMV infection and could be used as disease biomarkers.


Assuntos
Infecções por Citomegalovirus/congênito , Citomegalovirus/genética , MicroRNAs/sangue , Antivirais , Biomarcadores/sangue , Infecções por Citomegalovirus/sangue , DNA Viral/urina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase em Tempo Real
7.
Phys Rev Lett ; 116(8): 087201, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26967439

RESUMO

We present single-crystal neutron scattering measurements of the spin-1/2 equilateral triangular-lattice antiferromagnet Ba_{3}CoSb_{2}O_{9}. Besides confirming that the Co^{2+} magnetic moments lie in the ab plane for zero magnetic field and then determining all the exchange parameters of the minimal quasi-2D spin Hamiltonian, we provide conclusive experimental evidence of magnon decay through observation of intrinsic line broadening. Through detailed comparisons with the linear and nonlinear spin-wave theories, we also point out that the large-S approximation, which is conventionally employed to predict magnon decay in noncollinear magnets, is inadequate to explain our experimental observation. Thus, our results call for a new theoretical framework for describing excitation spectra in low-dimensional frustrated magnets under strong quantum effects.

8.
Phys Rev Lett ; 114(16): 161101, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25955041

RESUMO

We report on a new constraint on gravitylike short-range forces, in which the interaction charge is mass, obtained by measuring the angular distribution of 5 Å neutrons scattering off atomic xenon gas. Around 10^{7} scattering events were collected at the 40 m small angle neutron scattering beam line located at the HANARO research reactor of the Korean Atomic Energy Research Institute. The extracted coupling strengths of new forces in the Yukawa-type parametrization are g[over ^]^{2}=(0.2±6.8±2.0)×10^{-15} GeV^{-2} and g[over ^]^{2}=(-5.3±9.0_{-2.8}^{+2.7})×10^{-17} GeV^{-2} for interaction ranges of 0.1 and 1.0 nm, respectively. These strengths correspond to 95% confidence level limits of g^{2}<(1.4±0.2)×10^{-14} GeV^{-2} and g^{2}<(1.3±0.2)×10^{-16} GeV^{-2}, improving the current limits for interaction ranges between 4 and 0.04 nm by a factor of up to 10.

9.
Osteoarthritis Cartilage ; 22(11): 1861-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25046534

RESUMO

OBJECTIVE: Temporomandibular joint (TMJ) diseases predominantly afflict women, suggesting a role for female hormones in the disease process. However, little is known about the role of estrogen receptor (ER) signaling in regulating mandibular condylar cartilage growth. Therefore, the goal of this study was to examine the effects of altered estrogen levels on the mandibular condylar cartilage in wild type (WT) and ER beta Knockout (KO) mice. MATERIALS AND METHODS: 21-day-old female WT (n = 37) and ER beta KO mice (n = 36) were either sham operated or ovariectomized, and treated with either placebo or estradiol. The mandibular condylar cartilage was evaluated by histomorphometry, proliferation was analyzed by double ethynyl-2'-deoxyuridine/bromodeoxyuridine (EdU/BrdU) labeling, and assays on gene and protein expression of chondrocyte maturation markers were performed. RESULTS: In WT mice, ovariectomy caused a significant increase in mandibular condylar cartilage cell numbers, a significant increase in Sox9 expression and a significant increase in proliferation compared with sham operated WT mice. In contrast, ovariectomy did not cause any of these effects in the ER beta KO mice. Estrogen replacement treatment in ovariectomized WT mice caused a significant decrease in ER alpha expression and a significant increase in Sost expression compared with ovariectomized mice treated with placebo. Estrogen replacement treatment in ovariectomized ER beta KO mice caused a significant increase in Col2 expression, no change in ER alpha expression, and a significant increase in Sost expression. CONCLUSION: Estrogen via ER beta inhibits proliferation and ER alpha expression while estrogen independent of ER beta induces Col2 and Sost expression.


Assuntos
Receptor beta de Estrogênio/genética , Estrogênios/genética , Regulação da Expressão Gênica no Desenvolvimento , Côndilo Mandibular/crescimento & desenvolvimento , RNA/genética , Transtornos da Articulação Temporomandibular/genética , Articulação Temporomandibular/crescimento & desenvolvimento , Proteínas Adaptadoras de Transdução de Sinal , Animais , Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/metabolismo , Modelos Animais de Doenças , Receptor beta de Estrogênio/biossíntese , Receptor beta de Estrogênio/uso terapêutico , Estrogênios/biossíntese , Estrogênios/uso terapêutico , Feminino , Glicoproteínas/biossíntese , Glicoproteínas/genética , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Côndilo Mandibular/metabolismo , Camundongos , Camundongos Knockout , Articulação Temporomandibular/efeitos dos fármacos , Articulação Temporomandibular/metabolismo , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Transtornos da Articulação Temporomandibular/metabolismo
10.
Phys Rev Lett ; 112(7): 071101, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579585

RESUMO

Ultracold neutrons (UCNs) can be bound by the potential of terrestrial gravity and a reflecting mirror. The wave function of the bound state has characteristic modulations. We carried out an experiment to observe the vertical distribution of the UCNs above such a mirror at the Institut Laue-Langevin in 2011. The observed modulation is in good agreement with that prediction by quantum mechanics using the Wigner function. The spatial resolution of the detector system is estimated to be 0.7 µm. This is the first observation of gravitationally bound states of UCNs with submicron spatial resolution.

11.
Infect Immun ; 82(5): 1904-13, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566623

RESUMO

The interleukin-1 receptor antagonist (IL-1Ra) binds to IL-1 receptors and inhibits IL-1 activity. However, it is not clear whether IL-1Ra plays a protective role in periodontal disease. This study was undertaken to compare experimental periodontitis induced by Aggregatibacter actinomycetemcomitans in IL-1Ra knockout (KO) mice and wild-type (WT) mice. Computed tomography (CT) analysis and hematoxylin-and-eosin (H&E) and tartrate-resistant acid phosphatase (TRAP) staining were performed. In addition, osteoblasts were isolated; the mRNA expression of relevant genes was assessed by real-time quantitative PCR (qPCR); and calcification was detected by Alizarin Red staining. Infected IL-1Ra KO mice exhibited elevated (P, <0.05) levels of antibody against A. actinomycetemcomitans, bone loss in furcation areas, and alveolar fenestrations. Moreover, protein for tumor necrosis factor alpha (TNF-α) and IL-6, mRNA for macrophage colony-stimulating factor (M-CSF), and receptor activator of NF-κB ligand (RANKL) in IL-1Ra KO mouse osteoblasts stimulated with A. actinomycetemcomitans were increased (P, <0.05) compared to in WT mice. Alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OCN)/bone gla protein (BGP), and runt-related gene 2 (Runx2) mRNA levels were decreased (P, <0.05). IL-1α mRNA expression was increased, and calcification was not observed, in IL-1 Ra KO mouse osteoblasts. In brief, IL-1Ra deficiency promoted the expression of inflammatory cytokines beyond IL-1 and altered the expression of genes involved in bone resorption in A. actinomycetemcomitans-infected osteoblasts. Alterations consistent with rapid bone loss in infected IL-Ra KO mice were also observed for genes expressed in bone formation and calcification. In short, these data suggest that IL-1Ra may serve as a potential therapeutic drug for periodontal disease.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Doenças Ósseas Metabólicas/etiologia , Reabsorção Óssea/etiologia , Inflamação/etiologia , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Infecções por Pasteurellaceae/complicações , Periodontite/complicações , Animais , Regulação da Expressão Gênica , Proteína Antagonista do Receptor de Interleucina 1/genética , Fator Estimulador de Colônias de Macrófagos/genética , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Infecções por Pasteurellaceae/microbiologia , Periodontite/microbiologia , Ligante RANK/genética , Ligante RANK/metabolismo
12.
Phys Rev Lett ; 112(3): 034802, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24484144

RESUMO

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

13.
Int J Tuberc Lung Dis ; 18(2): 174-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24429309

RESUMO

SETTING: Both depression and tuberculosis (TB) are global public health problems that have a substantial impact on human health. However, depressive state among TB patients has not been well investigated in the Philippines. OBJECTIVE: To assess depressive state among pulmonary tuberculosis (PTB) patients and to identify factors associated with depressive state in Manila, the Philippines. DESIGN: A cross-sectional survey of PTB patients was conducted at 10 public health centres and two non-government organisation clinics providing directly observed treatment in District I, Tondo, Manila. Face-to-face interviews with 561 PTB patients using a structured questionnaire were conducted. RESULTS: Depressive state was observed in 16.8% of the participants. Logistic regression analysis indicated that body mass index < 18.5 kg/m(2), marital status of cohabitation compared with married, four or more symptoms, four or more adverse drug reactions, grade 3 or higher on the Medical Research Council dyspnoea scale and low perceived confidant social support were significantly associated with depressive state. CONCLUSION: Depressive state among PTB patients in economically depressed areas is common, and screening for depression in the primary care setting can identify patients who need support and treatment, especially for malnourished patients and those with poor social support.


Assuntos
Depressão/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/efeitos adversos , Distribuição de Qui-Quadrado , Estudos Transversais , Depressão/diagnóstico , Depressão/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , Desnutrição/epidemiologia , Estado Civil , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Percepção , Filipinas/epidemiologia , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Apoio Social , Inquéritos e Questionários , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/psicologia , Adulto Jovem
14.
Neuroscience ; 248: 664-9, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23811398

RESUMO

Reproductive success depends on a robust and appropriately timed preovulatory luteinizing hormone (LH) surge, which is induced by the activation of gonadotropin-releasing hormone (GnRH) neurons in response to positive feedback from increasing estrogen levels. Here we document an increase in postsynaptic GluR2-lacking Ca2+ -permeable AMPA-type glutamate receptors (CP-AMPARs) at synapses on GnRH neurons on the day of proestrus in rats, coincident with the increase in estrogen levels. Functional blockade of CP-AMPARs depressed the synaptic responses only on the day of proestrus and concomitantly attenuated the LH surge. Thus, the phasic synaptic incorporation of postsynaptic CP-AMPARs on GnRH neurons is involved in the generation of the LH surge.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/sangue , Receptores de AMPA/fisiologia , Sinapses/fisiologia , Animais , Estrogênios/fisiologia , Feminino , Técnicas In Vitro , Neurônios/fisiologia , Ratos , Ratos Wistar , Reprodução
15.
J Periodontal Res ; 48(6): 748-56, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23586622

RESUMO

BACKGROUND AND OBJECTIVE: The interleukin (IL)-1 receptor antagonist (Ra) binds to IL-1 receptors and inhibits IL-1 activity. However, it is unclear whether the IL-1Ra plays a protective role in periodontal disease. The purpose of this study was to compare IL-1Ra knockout (KO) and wild-type (WT) mice in regard to proinflammatory cytokine production, osteoclast formation and bone resorption in response to periodontal bacterial lipopolysaccharide (LPS). MATERIAL AND METHODS: Peritoneal macrophages (Mφs) were obtained from 13-wk-old IL-1Ra KO and WT mice. Peritoneal Mφs were cultured with or without 10 µg/mL of Aggregatibacter actinomycetemcomitans LPS for 24 h. The levels of IL-1alpha (IL-1α), IL-1beta (IL-1ß), tumor necrosis factor-α (TNF-α) and IL-6 were measured in periotoneal Mφs supernatant fluid (PM-SF) using an ELISA. Bone marrow cells were obtained from the mice and stimulated with PM-SF for 9 d, then stained with TRAP. The frequency of TRAP-positive multinucleated giant cell formation was calculated based on a fusion index. PM-SF-stimulated calvarial bone resorption was analyzed using micro-computed tomography, and calvarial histological analysis was performed using hematoxylin and eosin and TRAP staining. The expression of cyclooxygenase-2 (Cox2), prostanoid receptor EP4 (Ep4) and Rank mRNAs in bone marrow cells were measured using real-time quantitative PCR, while prostaglandin E2 (PGE2 ) production was determined by ELISA. RESULTS: The levels of IL-1α, IL-1ß, TNF-α and IL-6 in IL-1Ra KO mice PM-SF stimulated with A. actinomycetemcomitans LPS were significantly increased by approximately 4- (p < 0.05), 5- (p < 0.05), 1.3- (p < 0.05) and 6- (p < 0.05) fold, respectively, compared with the levels in WT mice. Moreover, osteoclast formation, expression of Rank, Ep4 and Cox2 mRNAs and production of PGE2 were significantly increased by approximately 2- (p < 0.05), 1.6- (p < 0.05), 2.5- (p < 0.05), 1.6- (p < 0.05) and 1.9- (p < 0.05) fold, respectively, in IL-1Ra KO mice stimulated with A. actinomycetemcomitans LPS compared with WT mice. CONCLUSION: IL-1Ra regulates IL-1 activity and appears to reduce the levels of other inflammatory cytokines, including TNF-α and IL-6, while it also reduces expression of the EP4 receptor related to prostanoid sensitivity and osteoclast formation. These results suggest that IL-1Ra is an important molecule for inhibition of inflammatory periodontal bone resorption.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Citocinas/efeitos dos fármacos , Dinoprostona/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Lipopolissacarídeos/farmacologia , Osteoclastos/efeitos dos fármacos , Regulação para Cima , Fosfatase Ácida/análise , Animais , Células da Medula Óssea/efeitos dos fármacos , Reabsorção Óssea/imunologia , Técnicas de Cultura de Células , Ciclo-Oxigenase 2/efeitos dos fármacos , Células Gigantes/efeitos dos fármacos , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1alfa/análise , Interleucina-1beta/efeitos dos fármacos , Interleucina-6/análise , Isoenzimas/análise , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Camundongos Knockout , Receptor Ativador de Fator Nuclear kappa-B/efeitos dos fármacos , Receptores de Prostaglandina E Subtipo EP4/efeitos dos fármacos , Crânio/imunologia , Fosfatase Ácida Resistente a Tartarato , Fator de Necrose Tumoral alfa/efeitos dos fármacos
16.
Neuroscience ; 237: 151-60, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23396087

RESUMO

General anesthesia is occasionally associated with postoperative complications such as sleep disorder, drowsiness, or mood alterations. Hippocampal acetylcholine (ACh), the extracellular level of which increases during the dark (active) phase and decreases during the light (rest) phase in rats, is thought to be associated with locomotor activity and be crucial for learning and memory. Propofol, an intravenous anesthetic, is known to shift the circadian rhythms of physiological parameters including locomotor activity and body temperature in both rodents and humans, while the effects of volatile anesthetics on the circadian rhythm largely remain unclear. The present study examined the effects of isoflurane anesthesia on the diurnal changes in hippocampal ACh release and locomotor activity in rats. Rats were divided into three groups: a light-phase anesthesia group (LA group), a dark-phase anesthesia group (DA group), and a control group. They were exposed to a 12-h light/12-h dark environment and anesthetized with 1.4% isoflurane for 4h during the middle of the light phase (LA group) and dark phase (DA group). Simultaneous measurement of hippocampal ACh by microdialysis and locomotor activity were done for 60h under free-moving conditions. Hippocampal ACh release and locomotor activity showed a clear circadian rhythm. In the DA group, but not in the LA group, the diurnal variation in ACh release was significantly disturbed and a more than 2-h phase-advance in locomotor activity was observed. There was a significant correlation between hippocampal ACh release and locomotor activity, and isoflurane anesthesia disrupted it even after anesthesia was discontinued. This study revealed that the levels and circadian rhythms of hippocampal ACh release and locomotor activity were more sensitive to isoflurane anesthesia when it was administered during the active phase. Our findings suggest that anesthesia exerts differential effects on the regulation of circadian rhythms depending on the circadian phase.


Assuntos
Acetilcolina/metabolismo , Anestésicos Inalatórios/farmacologia , Ritmo Circadiano/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Isoflurano/farmacologia , Atividade Motora/efeitos dos fármacos , Análise de Variância , Animais , Ritmo Circadiano/fisiologia , Relação Dose-Resposta a Droga , Masculino , Microdiálise , Ratos , Ratos Wistar , Estatística como Assunto
17.
Phys Rev Lett ; 109(6): 067204, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-23006301

RESUMO

We study a frustrated quantum Ising model relevant for Ca3Co2O6 that consists of a triangular lattice of weakly coupled ferromagnetic chains. According to our quantum Monte Carlo simulations, the chains become ferromagnetic and form a three-sublattice "up-up-down" structure for T≤T(CI). In contrast, long-wavelength spin-density-wave microphases are stabilized along the chains for T(CI)

18.
Biol Trace Elem Res ; 149(2): 280-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22576983

RESUMO

Lithium as an essential element for human life is still a subject of controversy. However, it is accepted that it does have profound neurological effects and is a valuable treatment for bipolar disease. Generally, it occurs in barely trace amounts in groundwater with few major exceptions. One of these is the Northern area of Chile where all potable water and many of the food stuffs contain high levels of lithium; between 100 and 10,000 times higher than most rivers in North America. Inevitably, the local population has been exposed to these levels in their drinking water for as long as the region has been populated. The present report details lithium levels in all the surface water sources of Northern Chile with comparison to that elsewhere. The implications for the local population are discussed and their situation compared to those exposed to other sources of lithium pollution.


Assuntos
Exposição Ambiental/análise , Lítio/análise , Chile , Poluição Ambiental/análise
19.
Phys Rev Lett ; 108(9): 097202, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22463664

RESUMO

We demonstrate multiferroic behavior in trimerized Mott insulators through the interplay between spins and electric dipole moments resulting from electronic charge fluctuations in frustrated units. The model consists of stacked triangular layers of trimers with small intertrimer exchange interactions J' and J''. Ferroelectric states coexist with ferro- or antiferromagnetic orderings depending on the value of the magnetic field H and the sign of the interlayer exchange J''. The electric polarization undergoes abrupt changes as a function of H.

20.
Anaesthesia ; 66(10): 895-900, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21770906

RESUMO

We compared the effects of the Airway Scope(®) on haemodynamic responses during tracheal intubation with those of direct laryngoscopy in normotensive and hypertensive patients. The systolic blood pressure, diastolic blood pressures and heart rate were recorded: (a) before anaesthesia; (b) immediately before intubation; (c) at intubation; and (d) 1, 2, 3, 4 and 5 min after intubation. In normotensive patients, the increase in blood pressure and heart rate over time were significantly lower with the Airway Scope than with the Macintosh laryngoscope (p < 0.003). In hypertensive patients, however, there was no difference in the changes over time in any of these haemodynamic measures between the two devices (p > 0.05). We conclude that the Airway Scope attenuates haemodynamic responses to tracheal intubation in comparison with the laryngoscope in normotensive but not in hypertensive patients. You can respond to this article at http://www.anaesthesiacorrespondence.com.


Assuntos
Hemodinâmica/fisiologia , Hipertensão/fisiopatologia , Intubação Intratraqueal/instrumentação , Laringoscópios , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Feminino , Glote/fisiologia , Frequência Cardíaca/fisiologia , Rouquidão/epidemiologia , Rouquidão/etiologia , Humanos , Laringoscopia , Masculino , Pessoa de Meia-Idade , Faringite/epidemiologia , Faringite/etiologia , Complicações Pós-Operatórias/epidemiologia , Tamanho da Amostra , Adulto Jovem
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