RESUMO
The periodontal pathogen Tannerella forsythia has the unique ability to produce methylglyoxal (MGO), an electrophilic compound which can covalently modify amino acid side chains and generate inflammatory adducts known as advanced glycation endproducts (AGEs). In periodontitis, concentrations of MGO in gingival-crevicular fluid are increased and are correlated with the T. forsythia load. However, the source of MGO and the extent to which MGO may contribute to periodontal inflammation has not been fully explored. In this study we identified a functional homolog of the enzyme methylglyoxal synthase (MgsA) involved in the production of MGO in T. forsythia. While wild-type T.forsythia produced a significant amount of MGO in the medium, a mutant lacking this homolog produced little to no MGO. Furthermore, compared with the spent medium of the T. forsythia parental strain, the spent medium of the T. forsythia mgsA-deletion strain induced significantly lower nuclear factor-kappa B activity as well as proinflammogenic and pro-osteoclastogenic cytokines from THP-1 monocytes. The ability of T. forsythia to induce protein glycation endproducts via MGO was confirmed by an electrophoresis-based collagen chain mobility shift assay. Together these data demonstrated that T. forsythia produces MGO, which may contribute to inflammation via the generation of AGEs and thus act as a potential virulence factor of the bacterium.
Assuntos
Citocinas/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Monócitos/metabolismo , Aldeído Pirúvico/metabolismo , Tannerella forsythia/patogenicidade , Humanos , Inflamação/microbiologia , Periodontite/microbiologia , Células THP-1 , Fatores de VirulênciaRESUMO
We have performed spin- and angle-resolved photoemission spectroscopy on tungsten (110) interfaced with an ultrathin iron (Fe) layer to study an influence of ferromagnetism on the Dirac-cone-like surface-interface states. We found an unexpectedly large energy gap of 340 meV at the Dirac point, and have succeeded in switching the Dirac-fermion mass by controlling the direction of Fe spins (in plane or out of plane) through tuning the thickness of the Fe overlayer or adsorbing oxygen on it. Such a manipulation of Dirac-fermion mass via the magnetic proximity effect opens a promising platform for realizing new spintronic devices utilizing a combination of exchange and Rashba-spin-orbit interactions.
RESUMO
Hematopoietic cell transplantation (HCT) is used for treatment of hematopoietic diseases. Assessment of T- and B-cell reconstitution after HCT is crucial because poor immune recovery has a major effect on the clinical course. In this study, we retrospectively analyzed T-cell receptor excision circles (TRECs) as well as signal and coding joint kappa-deleting recombination excision circles (sjKRECs and cjKRECs, respectively) as markers of newly produced lymphocytes in 133 patients (56 primary immunodeficient and 77 malignant cases, median (range): 12 (0-62) years old). We analyzed the kinetics of TREC and KREC recovery and determined the factors that contributed to better immune recovery. KRECs became positive earlier than TRECs and increased thereafter. Younger recipient age had a favorable effect on recovery of sjKRECs and cjKRECs. Compared with BM and peripheral blood, our data suggested that cord blood (CB) provided rapid B-cell recovery. CB also provided better B-cell neogenesis in adult HCT recipients. Chronic GVHD was associated with low TRECs, but not increased sjKRECs/cjKRECs. Finally, positive sjKRECs 1 month after HCT were associated with fewer infectious episodes. Monitoring of TRECs and KRECs may serve as a useful tool for assessment of immune reconstitution post HCT.
Assuntos
Linfócitos B/citologia , Sangue Fetal/transplante , Doenças Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Adolescente , Adulto , Linfócitos B/imunologia , Criança , Pré-Escolar , Feminino , Doenças Hematológicas/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T/sangue , Receptores de Antígenos de Linfócitos T/imunologia , Estudos Retrospectivos , Condicionamento Pré-Transplante/métodos , Adulto JovemRESUMO
The emission of low-energy electrons from H2O has been investigated at photon excitation energies in the vicinity of the O 1s ionization threshold. Neutral oxygen Rydberg atoms (O*) were found to form, and the correlation between the initial inner-shell excited state of H2O and the Rydberg state of O* was determined. The initially excited electron in a Rydberg orbital is shown to remain associated with O* even after the cleavage of two O-H bonds. We also show that the energy discrepancy between two Rydberg states of H2O and O* can be explained by the influence of the post-collision interaction, which becomes stronger as the excitation energy approaches the 1s ionization threshold.
RESUMO
Periodontal disease is caused by a group of bacteria that utilize a variety of strategies and molecular mechanisms to evade or overcome host defenses. Recent research has uncovered new evidence illuminating interesting aspects of the virulence of these bacteria and their genomic variability. This paper summarizes some of the strategies utilized by the major species - Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis - implicated in the pathogenesis of periodontal disease. Whole-genome sequencing of 14 diverse A. actinomycetemcomitans strains has revealed variations in their genetic content (ranging between 0.4% and 19.5%) and organization. Strikingly, isolates from human periodontal sites showed no genomic changes during persistent colonization. T. forsythia manipulates the cytokine responses of macrophages and monocytes through its surface glycosylation. Studies have revealed that bacterial surface-expressed O-linked glycans modulate T-cell responses during periodontal inflammation. Periodontal pathogens belonging to the "red complex" consortium express neuraminidases, which enables them to scavenge sialic acid from host glycoconjugates. Analysis of recent data has demonstrated that the cleaved sialic acid acts as an important nutrient for bacterial growth and a molecule for the decoration of bacteria surfaces to help evade the host immune attack. In addition, bacterial entry into host cells is also an important prerequisite for the lifestyle of periodontal pathogens such as P. gingivalis. Studies have shown that, after its entry into the cell, this bacterium uses multiple sorting pathways destined for autophagy, lysosomes, or recycling pathways. In addition, P. gingivalis releases outer membrane vesicles which enter cells via endocytosis and cause cellular functional impairment.
Assuntos
Bactérias/patogenicidade , Doenças Periodontais/microbiologia , Bactérias/genética , Bactérias/isolamento & purificação , Transporte Biológico , Genoma Bacteriano , Glicosilação , Humanos , Neuraminidase/metabolismoRESUMO
Chronic granulomatous disease (CGD) results from an inherited defect in the phagocytic cells of the immune system. It is a genetically heterogenous disease caused by defects in one of the five major subunits of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. There is a paucity of data from India on CGD. We herein describe the clinical features in 17 children with CGD from a single tertiary referral center in India. A detailed analysis of the clinical features, laboratory investigations and outcome of 17 children 7 with X-linked (XL) and 10 with autosomal recessive (AR) form was performed. Diagnosis of CGD was based on an abnormal granulocyte oxidative burst evaluated by either Nitroblue Tetrazolium (NBT) test or flow cytometry based Dihyrorhodamine 123 assay or both. The molecular diagnosis was confirmed by genetic mutation analysis in 13 cases. The mean age at diagnosis and the age at onset of symptoms was significantly lower in children diagnosed with XL- CGD compared those with AR disease. Mutations were detected in CYBB gene in 6 patients with XL-CGD and NCF-1 gene mutations were observed in 7 cases of AR- CGD. The course and outcome of the disease was much worse in children diagnosed with X-linked form of disease compared to AR forms of the disease; 4/7 (57%) children with X-CGD were dead at the time of data analysis. This is one of the largest series on chronic granulomatous disease from any developing country.
Assuntos
Doença Granulomatosa Crônica/epidemiologia , Centros de Atenção Terciária , Idade de Início , Causas de Morte , Criança , Pré-Escolar , Feminino , Seguimentos , Doença Granulomatosa Crônica/complicações , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/genética , Mortalidade Hospitalar , Humanos , Índia , Lactente , Recém-Nascido , Infecções/etiologia , Infecções/microbiologia , Masculino , Mutação , PrognósticoRESUMO
Tannerella forsythia is a pathogen implicated in periodontitis, an inflammatory disease of the tooth-supporting tissues often leading to tooth loss. This key periodontal pathogen is decorated with a unique glycan core O-glycosidically linked to the bacterium's proteinaceous surface (S)-layer lattice and other glycoproteins. Herein, we show that the terminal motif of this glycan core acts to modulate dendritic cell effector functions to suppress T-helper (Th)17 responses. In contrast to the wild-type bacterial strain, infection with a mutant strain lacking the complete S-layer glycan core induced robust Th17 and reduced periodontal bone loss in mice. Our findings demonstrate that surface glycosylation of this pathogen may act to ensure its persistence in the host likely through suppression of Th17 responses. In addition, our data suggest that the bacterium then induces the Toll-like receptor 2-Th2 inflammatory axis that has previously been shown to cause bone destruction. Our study provides a biological basis for pathogenesis and opens opportunities in exploiting bacterial glycans as therapeutic targets against periodontitis and a range of other infectious diseases.
Assuntos
Interações Hospedeiro-Patógeno/imunologia , Imunomodulação , Glicoproteínas de Membrana/imunologia , Polissacarídeos Bacterianos/imunologia , Células Th17/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Bactérias/genética , Bactérias/imunologia , Bactérias/patogenicidade , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Citocinas/biossíntese , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Gengiva/imunologia , Gengiva/microbiologia , Glicosilação , Camundongos , Mutação , NF-kappa B/metabolismo , Infiltração de Neutrófilos/imunologia , Osteoclastos/metabolismo , Virulência/genética , Virulência/imunologiaRESUMO
The major functions required for load-bearing orthopaedic implants are load-bearing and mechanical or biological fixation with the surrounding bone. Porous materials with appropriate mechanical properties and adequate pore structure for fixation are promising candidates for load-bearing implant material. In previous work, the authors developed a novel titanium (Ti) foam sheet 1-2mm thick by an original slurry foaming method. In the present work, novel Ti foam is developed with mechanical properties compatible with cortical bone and biological fixation capabilities by layer-by-layer stacking of different foam sheets with volumetric porosities of 80% and 17%. The resulting multilayer Ti foam exhibited a Young's modulus of 11-12GPa and yield strength of 150-240MPa in compression tests. In vitro cell culture on the sample revealed good cell penetration in the higher-porosity foam (80% volumetric porosity), which reached 1.2mm for 21 days of incubation. Cell penetration into the high-porosity layers of a multilayer sample was good and not influenced by the lower-porosity layers. Calcification was also observed in the high-porosity foam, suggesting that this Ti foam does not inhibit bone formation. Contradictory requirements for high volumetric porosity and high strength were attained by role-sharing between the foam sheets of different porosities. The unique characteristics of the present multilayer Ti foam make them attractive for application in the field of orthopaedics.
Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Titânio/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Força Compressiva/efeitos dos fármacos , Humanos , Microscopia de Fluorescência , Porosidade/efeitos dos fármacos , Pós , Resistência à Tração/efeitos dos fármacosRESUMO
The skeletal elements of embryonic limb are prefigured by prechondrogenic condensation in which secreted molecules such as adhesion molecules and extracellular matrix have crucial roles. However, how the secreted molecules are controlled to organize the condensation remains unclear. In this study, we examined metabolic regulation of secretion in prechondrogenic condensation, using bioluminescent monitoring systems. We here report on ATP oscillations in the early step of chondrogenesis. The ATP oscillations depended on both glycolysis and mitochondrial respiration, and their synchronization among cells were achieved via gap junctions. In addition, the ATP oscillations were driven by Ca(2+) oscillations and led to oscillatory secretion in chondrogenesis. Blockade of the ATP oscillations prevented cellular condensation. Furthermore, the degree of cellular condensation increased with the frequency of ATP oscillations. We conclude that ATP oscillations have a critical role in prechondrogenic condensation by inducing oscillatory secretion.
Assuntos
Trifosfato de Adenosina/metabolismo , Condrogênese/fisiologia , Mitocôndrias/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Animais , Cálcio/metabolismo , Contagem de Células , Linhagem Celular Tumoral , Junções Comunicantes/metabolismo , Genes Reporter , Glicólise , Humanos , Luciferases , Medições Luminescentes , Camundongos , Fosforilação Oxidativa , Células-Tronco/citologiaRESUMO
Periodontal pathogens, like any other human commensal or pathogenic bacterium, must possess both the ability to acquire the necessary growth factors and the means to adhere to surfaces or reside and survive in their environmental niche. Recent evidence has suggested that sialic acid containing host molecules may provide both of these requirements in vivo for several periodontal pathogens but most notably for the red complex organism Tannerella forsythia. Several other periodontal pathogens also possess sialic acid scavenging enzymes - sialidases, which can also expose adhesive epitopes, but might also act as adhesins in their own right. In addition, recent experimental work coupled with the release of several genome sequences has revealed that periodontal bacteria have a range of sialic acid uptake and utilization systems while others may also use sialic acid as a cloaking device on their surface to mimic host and avoid immune recognition. This review will focus on these systems in a range of periodontal bacteria with a focus on Ta. forsythia.
Assuntos
Bacteroides/enzimologia , Biofilmes/crescimento & desenvolvimento , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/metabolismo , Periodontite/microbiologia , Animais , Aderência Bacteriana , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Mimetismo Molecular , Periodontite/metabolismo , Fatores de VirulênciaRESUMO
Fragmentation of doubly charged ethanol clusters [(C(2)H(5)OH)(n)] following the O 1s ionization has been investigated by means of the photoelectron-photoion-photoion coincidence (PEPIPICO) method. The dominant fission channel of (C(2)H(5)OH)(n)(2+) was the formation of protonated cluster ion pairs [H(C(2)H(5)OH)(l)(+)/H(C(2)H(5)OH)(m)(+)]. The fragmentation mechanisms of these ion pairs were discussed based on the analysis of the PEPIPICO contour shape. It was clarified that the prominent fragmentation channel was a secondary decay mechanism, where neutral evaporation occurs after charge separation. On the other hand, the formation of small fragment ions was suppressed, excluding the formation of certain specific fragments (H(3)O(+), C(2)H(5)(+)/COH(+), and C(2)H(4)OH(+)). The formation of small fragment ions was suppressed due to the cooling effect caused by the neutral evaporation and the decrease in the electrostatic repulsive force caused by charge separation.
RESUMO
AIM: This study aimed to evaluate the effect of oral beraprost sodium, a prostaglandin I2 analogue, on symptoms of intermittent claudication in patients with arteriosclerosis obliterans. The research design consisted of a before and after treatment study without comparison groups. The subjects comprised arteriosclerosis obliterans patients who experienced intermittent claudication. Furthermore, this study aimed to assess the mechanism of action of beraprost sodium via blood sampling and measurements of flow-mediated vasodilatation before and after treatment. METHODS: The study was performed prospectively in 7 patients with arteriosclerosis obliterans. Beraprost sodium (40 microg) was orally administered to 7 patients at study entry, followed by administration of 120 microg/day for 12 weeks. Blood sampling and measurements of flow-mediated vasodilatation were performed before and after treatment at study entry, 4 weeks, and 12 weeks after treatment. Treadmill exercise tests were performed three times at study entry, 4 weeks, and 12 weeks after treatment. The ankle-brachial index (ABI) was measured at rest and after exercise. RESULTS: Pain-free walking distances increased by 138% at 12 weeks after treatment. Maximum walking distances increased by 133%. The ABI was significantly increased at 4 weeks and 12 weeks after treatment at rest. Endothelin-1 levels tended to be decreased at 1 h after administration of 40 microg beraprost sodium. N(G),N(G)-dimethyl-L-arginine, nitrate ions, and flow-mediated vasodilatation. CONCLUSION: Beraprost sodium tended to decrease endothelin-1 levels and improved symptoms of intermittent claudication in patients with arteriosclerosis obliterans.
Assuntos
Arteriosclerose Obliterante/tratamento farmacológico , Epoprostenol/análogos & derivados , Claudicação Intermitente/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Vasodilatadores/administração & dosagem , Administração Oral , Idoso , Índice Tornozelo-Braço , Arginina/análogos & derivados , Arginina/sangue , Arteriosclerose Obliterante/sangue , Arteriosclerose Obliterante/complicações , Arteriosclerose Obliterante/fisiopatologia , Biomarcadores/sangue , Endotelina-1/sangue , Epoprostenol/administração & dosagem , Teste de Esforço , Tolerância ao Exercício/efeitos dos fármacos , Humanos , Claudicação Intermitente/sangue , Claudicação Intermitente/etiologia , Claudicação Intermitente/fisiopatologia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Vasodilatação/efeitos dos fármacos , CaminhadaRESUMO
Toll-like receptor 9 (TLR9) expression is increased in periodontally diseased tissues compared with healthy sites indicating a possible role of TLR9 and its ligand, bacterial DNA (bDNA), in periodontal disease pathology. Here, we determine the immunostimulatory effects of periodontal bDNA in human monocytic cells (THP-1). THP-1 cells were stimulated with DNA of two putative periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia. The role of TLR9 in periodontal bDNA-initiated cytokine production was determined either by blocking TLR9 signaling in THP-1 cells with chloroquine or by measuring IL-8 production and nuclear factor-kappaB (NF-kappaB) activation in HEK293 cells stably transfected with human TLR9. Cytokine production (IL-1beta, IL-6, and TNF-alpha) was increased significantly in bDNA-stimulated cells compared with controls. Chloroquine treatment of THP-1 cells decreased cytokine production, suggesting that TLR9-mediated signaling pathways are operant in the recognition of DNA from periodontal pathogens. Compared with native HEK293 cells, TLR9-transfected cells demonstrated significantly increased IL-8 production (P < 0.001) and NF-kappaB activation in response to bDNA, further confirming the role of TLR9 in periodontal bDNA recognition. The results of PCR arrays demonstrated upregulation of proinflammatory cytokine and NF-kappaB genes in response to periodontal bDNA in THP-1 cells, suggesting that cytokine induction is through NF-kappaB activation. Hence, immune responses triggered by periodontal bacterial nucleic acids may contribute to periodontal disease pathology by inducing proinflammatory cytokine production through the TLR9 signaling pathway.
Assuntos
Bacteroides/imunologia , Citocinas/biossíntese , DNA Bacteriano/imunologia , Porphyromonas gingivalis/imunologia , Receptor Toll-Like 9/fisiologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Rim/citologia , Rim/embriologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Transfecção , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Hydrogen bonding in acetone clusters was investigated using near-edge x-ray absorption fine structure (NEXAFS) spectroscopy and density functional theory calculations in the carbon and oxygen K-edge regions. The partial-ion-yield (PIY) curves of the cluster ions were measured as the NEXAFS spectra of acetone clusters. In the carbon K-edge region, the first resonance peak, which was assigned to the C(CO) 1s-->pi( *)(C=O) resonance transition, showed no substantial change in the PIY curves of the acetone clusters, while the C(CH3) 1s-->3ppi(CH(3)) excitation feature was found to be strongly suppressed. The selective suppression of the C(CH3) 1s-->3ppi(CH(3)) resonance transition can be explained by the change in the character of the 3ppi(CH(3)) orbital due to the C=O...H-C type of hydrogen-bonding interaction. On the other hand, the NEXAFS spectra of the acetone molecule and clusters were almost identical in the oxygen K-edge region, except for a small shift in the pi( *)(C=O) resonance of 0.13 eV, because the character of the pi( *)(C=O) orbital remained, regardless of the C=O...H-C hydrogen bonding interaction.
Assuntos
Acetona/química , Carbono/química , Oxigênio/química , Elétrons , Ligação de Hidrogênio , Espectrometria de Massas , Modelos Moleculares , Conformação Molecular , Espectroscopia por Absorção de Raios XRESUMO
OBJECT: Clipping of an anterior communicating artery (A-com A) aneurysm requires various working angles for safe manipulation and observation. The lateral supraorbital keyhole approach provides a more lateral subfrontal corridor to observe and clip an A-com A aneurysm than the standard Perneczky method. METHODS: Preoperative planning was individualized in each patient based on three-dimensional computed tomography (3D-CT) angiography and 3D-CT osteotomy planning images. The procedure consisted of a 40-50 mm periorbital skin incision, partial dissection of the anterior portion of the temporal muscle, a 35 x 25 mm keyhole minicraniotomy from the supraorbital area to the sphenoid ridge, and opening of the carotid cistern and sylvian fissure in an antegrade fashion. Ten keyhole clipping procedures were performed in 10 patients with unruptured A-com A aneurysms. RESULTS: No shaving of scalp hair, drain placement, or anticonvulsant medication were required. No patient suffered neurological deficits or abnormal findings on postoperative magnetic resonance imaging. Most patients were discharged on the 2nd to 3rd postoperative days except for one patient who suffered from meningitis. CONCLUSIONS: The lateral supraorbital keyhole approach is a minimally invasive treatment option for relatively small and unruptured A-com A aneurysms.
Assuntos
Artéria Cerebral Anterior/cirurgia , Círculo Arterial do Cérebro/cirurgia , Craniotomia/métodos , Aneurisma Intracraniano/cirurgia , Idoso , Artéria Cerebral Anterior/diagnóstico por imagem , Artéria Cerebral Anterior/patologia , Placas Ósseas , Angiografia Cerebral/métodos , Círculo Arterial do Cérebro/diagnóstico por imagem , Círculo Arterial do Cérebro/patologia , Feminino , Osso Frontal/anatomia & histologia , Osso Frontal/cirurgia , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Cuidados Pré-Operatórios/métodos , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/métodos , Osso Esfenoide/anatomia & histologia , Osso Esfenoide/cirurgia , Instrumentos Cirúrgicos , Tomografia Computadorizada por Raios X/métodos , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: The presence of a projection from the primary motor cortex to the ipsilateral muscles has been established in human, but whether this pathway contributes to functional recovery after stroke is unclear. We investigated whether the ipsilateral tract is activated in hemiparetic stroke. METHODS: Motor-evoked potentials (MEPs) were simultaneously recorded from the bilateral trapezius or abductor digiti minimi (ADM) muscles after magnetic stimulation to the motor cortex in 40 acute stroke patients. RESULTS: At rest, ipsilateral trapezius MEPs were recordable in none of the 24 normal controls, and in 38% of the patients after stimulation to the non-affected hemisphere (P < 0.001). With voluntary contraction, ipsilateral trapezius MEPs were elicited in 21% of the normal controls and 73% of the patients (P < 0.001). Ipsilateral ADM MEPs were rarely recordable in both controls (0%) and patients (3%). The presence of ipsilateral trapezius MEPs was associated with less severe paresis in the trapezius (P = 0.04) and deltoid (P = 0.07), but not in the more distal muscles. CONCLUSIONS: The ipsilateral cortico-spinal tract is acutely facilitated after stroke in the trunk or proximal muscles, but not in the hand muscles. Activation of such pathway appears to partly compensate motor dysfunction of the trunk/proximal muscles.
Assuntos
Potencial Evocado Motor/fisiologia , Lateralidade Funcional , Tratos Piramidais/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Músculo Esquelético/fisiologia , Paresia/fisiopatologia , Estimulação Magnética TranscranianaRESUMO
Hydrogen bonding in methanol clusters has been investigated by using inner-shell photoabsorption spectroscopy and density functional theory (DFT) calculations in the carbon and oxygen K-edge regions. The partial-ion-yield (PIY) curves of H(CH(3)OH)(n)(+) were measured as the soft x-ray absorption spectra of methanol clusters. The first resonance peak in the PIY curves, which is assigned to the sigma*(O-H) resonance transition, exhibits a 1.20 eV blueshift relative to the total-ion-yield (TIY) curves of molecular methanol in the oxygen K-edge region, while it exhibits a shift of only 0.25 eV in the carbon K-edge region. Decreased intensities of the transitions to higher Rydberg orbitals were observed in the PIY curves of the clusters. The drastic change in the sigma*(O-H) resonance transition is interpreted by the change in the character of the sigma*(O-H) molecular orbital at the H-donating OH site due to the hydrogen-bonding interaction.
RESUMO
Oxidation reaction of the ground state Si atom was studied by using a crossed molecular beam technique at 13.0 kJ/mol of collision energy. The Si atomic beam was generated by laser vaporization and crossed with the oxygen molecular beam at right angle. Products at the crossing region were detected by the laser-induced fluorescence (LIF). The LIF of SiO(A 1 Pi-X 1 Sigma+) was used to determine the vibrational state distribution of the electronic ground state, SiO(X 1 Sigma+). The determined distribution was inverted with the maximum population at v"=4, and in good agreement with the recent quasiclassical trajectory calculation on the singlet potential energy surface. The agreement suggested that an abstraction mechanism is dominant at the collision energy studied here. One of the counterproducts, O(3PJ), was also observed by the vacuum ultraviolet LIF and the distribution of the spin-orbit levels were determined. The formation of O(3PJ) was consistent with the significant population of v"=7 and 8 states of SiO, which could be explained by the presence of the triplet product channel with higher exothermicity.
RESUMO
Malignant mesenchymoma is a soft tissue tumor arising preferentially in the extremities and retroperitoneum. We report a case of primary malignant mesenchymoma of the left posterior mediastinum. A 24-year-old woman was admitted to our hospital for complaining of cough. Chest X-ray showed a giant mass occupying the 2/3 of the left hemithorax. Chest computed tomography (CT) revealed a lobulated large mass with fat density area and calcified spot in the mediastinum and left pleural space. Chest magnetic resonance imaging (MRI) demonstrated a large solid mass consisting mainly of areas with the same intensity as fatty tissue and partly of areas with heterogenous moderate intensity. The tumor was resected completely under left posterolateral thoracotomy. The pathologic diagnosis was malignant mesenchymoma; well differentiated liposarcoma with osteocartilagenous differentiation. The patient has been well for 3 years and 3 months after surgery.