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1.
Eur J Surg Oncol ; 40(1): 49-54, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24075825

RESUMO

BACKGROUND: The surgical management of soft tissue sarcoma (STS) in elderly patients has only been addressed in a few studies. The objective of the current study was to assess surgical outcomes in patients with STS aged 70 years and older and the association of older age with the survival after complete resection. METHODS: A retrospective analysis was conducted in 158 elderly patients with localized STS who visited 11 institutions participating in Japanese Musculoskeletal Oncology Group between 1995 and 2006 and were treated by surgical resection. Univariate and multivariate analyses were performed to identify prognostic factors. RESULTS: Median follow-up period was 38 months. Histologically high-grade tumors were detected in 71% of the patients. Wide resection with adequate margins was performed in 66% of the cases. Systemic chemotherapy was performed in only 5 patients. Univariate analysis identified histological grade and gender as statistically significant prognostic factors for sarcoma-specific survival. Multivariate analysis did not identify significant prognostic factors for sarcoma-specific survival, although high grade sarcoma emerged as a potentially significant prognostic factor (P = 0.050). Local recurrence was detected in 19% of the patients. Multivariate analysis of local recurrence-free survival showed that tumor site and surgical margins were statistically significant prognostic factors. CONCLUSIONS: Older age was not identified as a prognostic factor for sarcoma-specific survival, which is not consistent with the findings of previous studies showing that older age was associated with decreased sarcoma-specific survival. Complete resection should be indicated and can lead to optimal treatment outcome for properly selected elderly patients.


Assuntos
Sarcoma/mortalidade , Sarcoma/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Gradação de Tumores , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores de Risco , Sarcoma/diagnóstico , Sarcoma/epidemiologia , Sarcoma/patologia , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
2.
J Synchrotron Radiat ; 20(Pt 2): 219-25, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23412477

RESUMO

A Si(111) winged crystal has been designed to minimize anticlastic bending and improve sagittal focusing efficiency. The crystal was thin with wide stiffening wings. The length-to-width ratio of the crystal was optimized by finite element analysis, and the optimal value was larger than the `golden value'. The analysis showed that the slope error owing to anticlastic bending is less than the Darwin width. The X-rays were focused two-dimensionally using the crystal and a tangentially bent mirror. The observed profiles of the focal spot agreed well with the results of a ray-tracing calculation in the energy range from 8 to 17.5 keV. X-ray diffraction measurements with a high signal-to-noise ratio using this focusing system were demonstrated for a small protein crystal.


Assuntos
Muramidase/química , Difração de Raios X/métodos , Animais , Cristalização/instrumentação , Desenho de Equipamento , Síncrotrons
3.
Eur J Pain ; 16(7): 994-1004, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22337641

RESUMO

Lysophosphatidic acid (LPA), an initiator of neuropathic pain, causes allodynia. However, few studies have evaluated the pharmacological profile of LPA-induced pain. In this study, a LPA-induced pain model was developed and pharmacologically characterized with clinically relevant drugs used for neuropathic pain, including antiepileptics, non-steroidal anti-inflammatory agents, analgesics, local anaesthetics/antiarrhythmics and antidepressants. Gabapentin (1-30 mg/kg, p.o.) significantly reversed LPA-induced allodynia, but neither indomethacin (30 mg/kg, p.o.) nor morphine (0.3-3 mg/kg, s.c.) did, which indicates that LPA-induced pain consists mostly of neuropathic rather than inflammatory pain. Both pregabalin (0.3-10 mg/kg, p.o.) and ω-CgTX MVIIA (0.01-0.03 µg/mouse, i.t.) completely reversed LPA-induced allodynia in a dose-dependent manner. Lidocaine (1-30 mg/kg, s.c.), mexiletine (1-30 mg/kg, p.o.) and carbamazepine (10-100 mg/kg, p.o.) significantly ameliorated LPA-induced allodynia dose dependently. Milnacipran (30 mg/kg, i.p.) produced no significant analgesic effect in LPA-induced allodynia. In LPA-injected mice, expression of the α2δ1 subunit of the voltage-gated calcium channel (VGCC) was increased in the dorsal root ganglion (DRG) and spinal dorsal horn. Furthermore, the VGCC current was potentiated in both the DRG from LPA-injected mice and LPA (1 µM)-treated DRG from saline-injected mice, and the potentiated VGCC current was amended by treatment with gabapentin (100 µM). The LPA-induced pain model described here mimics aspects of the neuropathic pain state, including the sensitization of VGCC, and may be useful for the early assessment of drug candidates to treat neuropathic pain.


Assuntos
Modelos Animais de Doenças , Hiperalgesia/induzido quimicamente , Lisofosfolipídeos , Neuralgia/induzido quimicamente , Aminas/farmacologia , Aminas/uso terapêutico , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Canais de Cálcio/metabolismo , Ácidos Cicloexanocarboxílicos/farmacologia , Ácidos Cicloexanocarboxílicos/uso terapêutico , Gabapentina , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Indometacina/farmacologia , Indometacina/uso terapêutico , Masculino , Camundongos , Morfina/farmacologia , Morfina/uso terapêutico , Atividade Motora/efeitos dos fármacos , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Pregabalina , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Ácido gama-Aminobutírico/análogos & derivados , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/uso terapêutico
5.
J Phys Condens Matter ; 23(1): 015902, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21406829

RESUMO

The electronic structure of BiFeO3 (BFO), BiFeO3-PbTiO(3) solid solution (BFO-PT), and Mn-doped BFO-PT (BFM-PT) films fabricated by chemical solution deposition was investigated by x-ray absorption fine structure (XAFS). The BiFeO3 shows a large leakage current owing to the mixed valance state of Fe(2 +) and Fe(3 +). The BFO film has a blunt absorption edge jump indicating the charge fluctuated state of the iron ions. The BFO-PT and BFM-PT films have sharp absorption edges, and the absorption energy of these films shifted to opposite energy. The valence fluctuation of the iron ions was closely connected with the leakage current properties. The charge fluctuated BFO film showed a leaky feature, and the charge unfluctuated BFO-PT and BFM-PT films had improved leakage current properties. The valence fluctuation of the iron ions can be controlled by Mn substitution and by making solid solutions.

6.
Clin Genet ; 80(5): 484-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21062273

RESUMO

Ohtahara syndrome (OS) is one of the most severe and earliest forms of epilepsy. We have recently identified that the de novo mutations of STXBP1 are important causes for OS. Here we report a paternal somatic mosaicism of an STXBP1 mutation. The affected daughter had onset of spasms at 1 month of age, and interictal electroencephalogram showed suppression-burst pattern, leading to the diagnosis of OS. She had a heterozygous c.902+5G>A mutation of STXBP1, which affects donor splicing of exon 10, resulting in 138-bp insertion of intron 10 sequences in the transcript. The mutant transcript had a premature stop codon, and was degraded by nonsense-mediated mRNA decay in lymphoblastoid cells derived from the patient. High-resolution melting analysis of clinically unaffected parental DNAs suggested that the father was somatic mosaic for the mutation, which was also suggested by sequencing. Cloning of PCR products amplified with the paternal DNA samples extracted from blood, saliva, buccal cells, and nails suggested that 5.3%, 8.7%, 11.9%, and 16.9% of alleles harbored the mutation, respectively. This is a first report of somatic mosaicism of an STXBP1 mutation, which has implications in genetic counseling of OS.


Assuntos
Epilepsia/genética , Mosaicismo , Proteínas Munc18/genética , Espasmos Infantis/genética , Pai , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
7.
Rev Sci Instrum ; 79(10): 10E706, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044524

RESUMO

Plasma density radial profile measurements are an important study for fusion plasma researches. We reconstructed a multichannel microwave interferometer for radial plasma electron density and density fluctuation measurements with both changing the transmission horn position and using the Teflon lens by only using this system in a single plasma shot. By using this system, we can successfully measure the radial density and density fluctuation spectra in a single plasma shot.

8.
Artigo em Inglês | MEDLINE | ID: mdl-18519197

RESUMO

We performed synchrotron X-ray topography on a La(3)Ta0(0.5)Ga (5.5)O(14) (LTG) crystal grown by the Czochralski method. Since a synchrotron X-ray source can provide high-energy X-rays, one can detect bulk structures by X-ray topography. LTG is one of the most attractive piezoelectric crystals along with La(3)Ga(5)SiO(14) (LGS) because of its excellent acoustic properties (temperature compensation of acoustic losses). Since LTG single crystals can be grown from a stoichiometric melt, it was expected that single crystals with better quality than the LGS crystal, which cannot be grown from a stoichiometric system but only from a congruent melt, can be obtained. However, 60 keV X-ray topography revealed that the LTG crystal quality was not as high as the LGS crystal quality. The crystal quality of the central region was lower than that of the surrounding region.


Assuntos
Cerâmica/química , Cristalização/métodos , Fenômenos Eletromagnéticos/métodos , Difração de Raios X , Teste de Materiais , Propriedades de Superfície
9.
Histol Histopathol ; 21(9): 969-77, 2006 09.
Artigo em Inglês | MEDLINE | ID: mdl-16763947

RESUMO

Although we have previously shown drastic cell death by pyruvate deficiency in osteoblasts at the proliferative stage, the exact mechanism remains unclear so far. Cell survivability was significantly decreased in rat calvarial osteoblasts cultured for 0 to 3 days in vitro (DIV) following replacement of the eutrophic alpha-modified minimum essential medium (alpha-MEM) with Dulbecco's modified eagle medium (DMEM) for cultivation. The addition of pyruvate enriched in alpha-MEM, but not in MEM, entirely prevented cell death induced by the medium replacement throughout a culture period from 0 to 3 DIV. Both cysteine and reduced glutathione protected cell death in cells cultured for 3 DIV without significantly affecting that in cells cultured for 1 DIV, however, while none of lactate, acetate and insulin significantly prevented the cell death irrespective of the culture period up to 3 DIV. A marked increase was detected in intracellular reactive oxygen species (ROS) levels 4 h after the medium replacement. In osteoblasts cultured in alpha-MEM for 3 DIV, but not in those for 7 DIV, hydrogen peroxide (H2O2) markedly decreased cell survivability when exposed for 2 to 24 h. Furthermore, H2O2 was effective in significantly decreasing cell survivability in osteoblasts cultured in DMEM for 7 DIV. Pyruvate at 1 mM not only prevented cell death by H2O2, but also suppressed the generation of intracellular ROS in osteoblasts exposed to H2O2. These results suggest that pyruvate could be cytoprotective through a mechanism associated with the anti-oxidative property rather than an energy fuel in cultured rat calvarial osteoblasts.


Assuntos
Antioxidantes/metabolismo , Osteoblastos/metabolismo , Ácido Pirúvico/farmacologia , Animais , Sobrevivência Celular , Células Cultivadas , Cisteína/química , Glutationa/química , Glutationa/metabolismo , Peróxido de Hidrogênio/farmacologia , Imuno-Histoquímica , Técnicas In Vitro , Modelos Biológicos , Ratos , Espécies Reativas de Oxigênio/metabolismo
10.
Histol Histopathol ; 21(7): 785-91, 2006 07.
Artigo em Inglês | MEDLINE | ID: mdl-16598677

RESUMO

Animal models of epilepsy have allowed the determination of the basic molecular and cellular mechanisms of epileptogenesis. Generalized limbic seizures and subsequent status epilepticus can be induced by either pilocarpine, the muscarinic acetylcholine receptor agonist or kainate, the glutamate receptor agonist. There has been increasing interest that chromatin remodeling might play a critical role in gene regulation even in non-dividing cells such as neurons. One form of chromatin remodeling is histone amino-terminal modification that can generate synergistic or antagonistic affinities for the interactions of transcriptional factors, in turn causing changes in gene activity. Two widely studied histone modification processes are histone acetylation and phosphorylation. While histone hyperacetylation indicates an increase in gene activity, its hypoacetylation marks gene repression. Both states are controlled by a dynamic interplay of histone acetyltransferase (HAT) and histone deacetylase (HDAC). We have found the upregulation of acetylation and phosphorylation of histones, coupled with status epilepticus after kainate administration. c-fos and c-jun mRNA have been sequentially induced in response to kainate, in different hippocampal subpopulations starting from the dentate gyrus and spreading to the cornus ammonis regions well correlated with the spatio-temporal distribution of histone H4 hyperacetylation. Both histone modifications are associated with the c-fos gene promoter after kainate stimulation, while only histone acetylation with the c-jun gene. Pretreatment with curcumin, which has a HAT inhibitory activity specific for CBP/p300, attenuates histone modifications, IEGs expression and also the severity of status epilepticus after kainate treatment. Histone modifications may have a crucial role in the development of epilepsy induced by kainate.


Assuntos
Agonistas de Aminoácidos Excitatórios/uso terapêutico , Histonas/metabolismo , Ácido Caínico/farmacologia , Estado Epiléptico , Acetilação , Animais , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/fisiologia , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Fosforilação , Receptores de Ácido Caínico/genética , Receptores de Ácido Caínico/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética , Estado Epiléptico/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia
11.
Neuroscience ; 134(4): 1123-31, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16019149

RESUMO

Pathological activation of microglia, which reside quiescently in physiological CNS, is associated with various neurodegenerative diseases. Endogenous polyamines, spermidine and spermine, are known to be activators of cell proliferation and differentiation. We previously reported that both spermidine and spermine induce dose-dependent cell death in cultured rat brain microglia at a submicromolar concentration range via apoptotic process, whereas cultured astrocytes were less sensitive to these polyamines [Neuroscience 120 (2003) 961]. These polyamine effects were observed only in the presence of fetal bovine serum. In the present study we examined further the mechanism of polyamine-induced microglial cell death. Amine oxidase in fetal bovine serum produces hydrogen peroxide and an aminoaldehyde from spermine, and the latter generates acrolein spontaneously. Acrolein was found to be much more toxic to microglia than to astrocytes and the effective concentration of acrolein was similar to that of spermine, whereas hydrogen peroxide was marginally toxic. Aminoguanidine, an inhibitor of amine oxidase, blocked the toxic effects of spermine on microglia. Spermine cytotoxicity was also prevented by antioxidant reagents; glutathione (reduced form), cysteine, and N-acetylcysteine. These results suggest that polyamine-induced apoptotic cell death of microglia is triggered by an oxidative stress with acrolein, which is produced by amine oxidase from polyamine. The different toxicities of polyamine between two glial cells may regulate the balance of glial activation in some pathological conditions of CNS.


Assuntos
Apoptose/fisiologia , Poliaminas Biogênicas/metabolismo , Poliaminas Biogênicas/farmacologia , Microglia/efeitos dos fármacos , Acroleína/metabolismo , Acroleína/farmacologia , Animais , Antioxidantes/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Glutationa/análise , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Microglia/metabolismo , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Diabet Med ; 22(8): 1098-100, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16026379

RESUMO

BACKGROUND: Laminar necrosis of the cerebral cortex characterized neuropathologically by delayed selective neuronal necrosis occurs in hypoglycaemic encephalopathy and other brain diseases. CASE REPORT: A 37-year-old male with insulin-treated Type 1 diabetes mellitus developed hypoglycaemic encephalopathy associated with respiratory failure. Brain diffusion-weighted MRI during the subacute period demonstrated high signals along the cerebral cortex. Brain single-photon emission computed tomography showed diffuse, severe cerebral hypoperfusion. The patient remained comatose and died 1 month later. CONCLUSIONS: High signals along the cortical bands on diffusion-weighted MRI suggest cortical laminar necrosis, although a postmortem examination was unavailable. Sustained hypoglycaemic brain injury, possibly associated with respiratory hypoxia, may be the underlying mechanism.


Assuntos
Encefalopatias Metabólicas/etiologia , Córtex Cerebral/patologia , Imagem de Difusão por Ressonância Magnética , Hipoglicemia/complicações , Adulto , Encefalopatias Metabólicas/diagnóstico , Evolução Fatal , Humanos , Hipoglicemia/patologia , Masculino , Necrose
13.
J Endocrinol ; 181(2): 233-44, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15128272

RESUMO

Neither expression nor functionality is clear in peripheral tissues with the molecular machineries required for excitatory neurotransmitter signaling by L-glutamate (Glu) in the central nervous system, while a recent study has shown that several Glu receptors are functionally expressed in the rat testis. This fact prompted us to explore the possible functional expression in the rat testis of the Glu transporters usually responsible for the regulation of extracellular Glu concentrations in the brain. RT-PCR revealed the expression, in the rat testis, of mRNA for five different subtypes of Glu transporters, in addition to that for particular subtypes of ionotropic and metabotropic Glu receptors. Glutamate transporter-1 (GLT-1) was different in the brain from that in the testis in terms of molecular sizes on Northern and Western blot analyses. In situ hybridization as well as immunohistochemical analysis showed localized expression of glutamate aspartate transporter at interstitial spaces and GLT-1 at elongated spermatids in the rat testis respectively. The expression of mRNA was localized for excitatory amino acid transporter-5 at the basal compartment of the seminiferous tubule in the rat testis. [(3)H]Glu was accumulated in testicular crude mitochondrial fractions in a temperature- and sodium-dependent saturable manner with pharmacological profiles similar to those shown in brain crude mitochondrial fractions. These results suggested that particular subtypes of central Glu transporters for the regulation of extracellular Glu concentrations in the rat testis could be constitutively and functionally expressed.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos , Células Fotorreceptoras , RNA Mensageiro/análise , Testículo/química , Sistema X-AG de Transporte de Aminoácidos/análise , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Animais , Northern Blotting/métodos , Western Blotting/métodos , Proteínas de Transporte/genética , Transportador 2 de Aminoácido Excitatório/genética , Transportador 5 de Aminoácido Excitatório , Proteínas de Transporte de Glutamato da Membrana Plasmática , Ácido Glutâmico/metabolismo , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Masculino , Ratos , Ratos Wistar , Receptores de Glutamato/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simportadores/genética , Testículo/metabolismo
14.
Neuroscience ; 120(4): 961-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12927202

RESUMO

Pathological activation of microglia, which reside quiescently in physiological CNS, contributes various neurodegenerative diseases. Endogenous polyamines, spermidine (SPD) and spermine (SPM) are known to be activators of cell proliferation and differentiation. We examined the effect of polyamines on microglial activation in culture. Cultured microglia prepared from the whole brains of newborn rats produced nitric oxide (NO) by the stimulation with lipopolysaccharide (LPS). LPS-induced NO production was markedly inhibited by SPD and SPM; half effective concentrations (EC(50)) of SPD and SPM were about 3 and 1 microM, respectively. Cell viability assessed by total mitochondrial activity decreased by the incubation with SPD and SPM for 24 h at similar concentration ranges. After the treatment with SPM for 24 h, the cells changed into small round morphology, and were strongly stained with propidium iodide. By the staining with bis-benzimide trihydrochloride, condensation and fragmentation of the nucleus were often observed. Semiquantitative analysis of fragmented DNA with enzyme-linked immunosorbent assay technique revealed that a large amount of fragmented DNA appeared in cytosol prior to disruption of the cell membrane. Fragmented DNA in the cytosol increased dose dependently with SPM; EC(50) was less than 10 microM. Furthermore, most of the cells after 24 h incubation with 10 microM SPD and SPM were positive for terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick end labeling. These results suggest that microglial cell death is induced by a low concentration of polyamines via an apoptotic process rather than necrotic one.


Assuntos
Morte Celular/efeitos dos fármacos , Microglia/efeitos dos fármacos , Poliaminas/farmacologia , Animais , Animais Recém-Nascidos , Benzimidazóis/metabolismo , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ensaio de Imunoadsorção Enzimática/métodos , Marcação In Situ das Extremidades Cortadas/métodos , Lipopolissacarídeos/farmacologia , Microglia/citologia , Nitritos/análise , Ratos , Fatores de Tempo
15.
Neuroscience ; 117(1): 37-42, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12605890

RESUMO

The functional changes of astrocytes are deeply involved in neurodegenerating processes of various CNS diseases. ATP is released during various neuronal damages such as brain ischemia and may control astrocyte functions. We examined the effect of ATP on the production of nitric oxide in the cultured astrocytes from rat embryo. The astrocytes were stimulated by lipopolysaccharide instead of pathological activation in vivo. Nitric oxide production was evaluated by the fluorometric assay of nitrite accumulated in the medium. The expression of inducible nitric oxide synthase was analyzed by Western blotting. Nitric oxide production induced by 1 ng/ml lipopolysaccharide was enhanced by ATP with maximal enhancement of three- to four-fold; a half-effective concentration was about 0.3 mM. In the absence of ATP, half-effective concentration of lipopolysaccharide on nitric oxide production was about 3 ng/ml; however, half-effective concentration shifted to 0.3 ng/ml in the presence of 1.5-mM ATP. Several other P2 receptor agonists (uridine triphosphate, ADP, adenosine monophosphate, 2'- and 3'-O - (4-benzoylbenzoyl)-ATP, and 2-methylthioATP) showed a similar enhancing effect, and an antagonist, ATP-2',3'-dialdehyde, showed an inhibiting effect. Western blotting analysis revealed that the extent of lipopolysaccharide-induced expression of nitric oxide synthase increased several-fold by the addition of ATP; half-effective concentration was about 0.5 mM. These results suggest that the extracellular ATP plays an important role as a transmitter and regulates astrocyte functions via a certain P2 receptor and that such a change in astrocyte function is involved in either protection or aggravation in neurodegenerative processes.


Assuntos
Trifosfato de Adenosina/farmacologia , Astrócitos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Óxido Nítrico/biossíntese , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Agonistas do Receptor Purinérgico P2 , Antagonistas do Receptor Purinérgico P2 , Ratos , Ratos Wistar , Receptores Purinérgicos P2/metabolismo
16.
Life Sci ; 70(9): 991-1001, 2002 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-11860158

RESUMO

The Na+-dependent, "high-affinity" transport of L-glutamate (GluT) in brain tissue has become a significant focus of interest, particularly since it has been revealed that abnormalities of GluT may be associated with serious neurological disorders. Using quantitative autoradiography on 3H-sensitive films, we have studied, in thaw-mounted sections of rat brain, the distribution and pharmacology of radioligand binding to sites with characteristics of the substrate-recognition/binding locus on GluT. The technique makes it possible to determine not only the intensity of binding in brain regions but, with a high level of precision, pharmacological constants such as IC50 or nH. [3H]L-aspartate and [3H]D-aspartate are two classical radioligands used in studies of GluT. We have determined IC50 values for the inhibition of [3H]L- and [3H]D-aspartate binding by their non-radioactive counterparts in the cerebral neocortex. hippocampus, striatum, septal nuclei and the cerebellar cortex. The two radioligands did not appreciably differ from each other in their interactions with the binding sites in the forebrain, consistent with all Na+-dependent GluT binding sites in that region having no stereoselectivity for aspartate enantiomers. In the cerebellar cortex, however, the data indicated the presence of a GluT binding site that preferred L- over D-aspartate. These findings contrast with many previous observations and suggest that the pharmacological characteristics of the ligand binding sites on GluT in the mammalian cerebellar cortex may have to be re-assessed and/or a possibility of an existence of (a) hitherto unknown molecule(s) with properties of a glutamate transporter be considered.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/metabolismo , Ácido Aspártico/metabolismo , Encéfalo/metabolismo , Ácido D-Aspártico/metabolismo , Sódio/fisiologia , Animais , Autorradiografia , Sítios de Ligação , Feminino , Secções Congeladas , Masculino , Ratos , Ratos Sprague-Dawley
17.
Ital J Anat Embryol ; 106(2 Suppl 1): 51-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11729997

RESUMO

In this study, the relation of P450scc expression and mitochondrial ultrastructure was examined in rat granulosa cells at the time of ovulation, and in the NIH/3T3 cells. Before ovulation in the ovary, granulosa cells of Graafian follicle which expressed only mRNA of P450scc had elongated mitochonria with lamellar cristae. After ovulation, granulosa lutein cells which expressed both P450scc mRNA and protein had oval and round mitochondria with tubular or vesicular cristae. Two different cytochrome P450scc cDNA fragments in length were subcloned into pEGFPN vector, transfected into NIH/3T3 cells, and the mitochondrial structure was examined under fluorescent microscope with GFP and by electron microscopy. 5'end of cytochrome P450scc contained mitochondrial localization signal, and was composed of about 40 amino acids. NIH/3T3 cells had filamentous and elongated mitochondria with lamellar cristae, free ribosomes, and rER. After the transfection of short fragment of SCC(scc-s:200bp), mitochondria remained filamentous and their cristae also remained lamellar. On the other hand, when almost full length of SCC fragment(scc-f:1.1kb) was transfected, globular and round mitochondria were labeled with GFP, and round or oval mitochondria with vesicular or tubular cristae could be examined by electron microscope. Our study suggests that cytochrome P450scc located in mitochondrial inner membrane plays an important role to determine the mitochondrial morphology in vivo and in vitro.


Assuntos
Diferenciação Celular/fisiologia , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Células da Granulosa/ultraestrutura , Membranas Intracelulares/ultraestrutura , Mitocôndrias/ultraestrutura , Ovulação/fisiologia , Esteroides/biossíntese , Células 3T3 , Animais , Cricetinae , Feminino , Células da Granulosa/metabolismo , Proteínas de Fluorescência Verde , Imuno-Histoquímica , Indicadores e Reagentes/metabolismo , Membranas Intracelulares/metabolismo , Proteínas Luminescentes/genética , Camundongos , Microscopia Eletrônica , Mitocôndrias/metabolismo , Ratos , Ratos Wistar
18.
Nihon Ronen Igakkai Zasshi ; 38(5): 651-8, 2001 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-11605214

RESUMO

To estimate the usefulness of the bedside swallowing assessment proposed by Smithard et al and neuroimaging findings characteristic for dysphagia, we studied the outcome of 102 patients with chronic cerebral infarction after assessment of swallowing by this test with brain computerized tomography (CT). All patients had a variety of motor disturbance and were admitted on a long-term medicare basis. They were divided into two groups according to the findings: the positive group (n = 33), who showed any of the listed types of difficulty in swallowing water, and the negative group (n = 69). Followed up to 2.2 years, their outcomes were studied. CT findings were studied on type of infarction, number and laterality of infarction, grade of periventricular lucency (PVL), presence of ventricular dilatation (VD), and severity of cortical atrophy (CA). The mean age was 76.4 years at registration and 61 were men. The frequency of severe dementia and disturbed ADL were significantly higher in the positive group. Eighteen patients died during the observation period and 15 of those were in the positive group, indicating higher annual death rate (29.9% vs 2.2% in the negative group). All of the 15 patients in the positive group died of pneumonia. CT findings showed high incidence of multiple infarction, bilateral hemispheric lesion, severe PVL, VD, and severe CA in the positive group. These findings indicated that this evaluation method was useful in screening swallow function for patients with cerebral infarction in the chronic phase. Furthermore, CT findings suggested that severe white matter lesion, VD, and severe CA as well as multiple infarction seen in bilateral hemisphere was related to dysphagia, probably due to multiple factors involving pyramidal- and extrapyramidal-tracts with higher brain function.


Assuntos
Encéfalo/diagnóstico por imagem , Infarto Cerebral/complicações , Transtornos de Deglutição/diagnóstico , Tomografia Computadorizada por Raios X , Adulto , Idoso , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito
19.
Bioorg Med Chem Lett ; 11(19): 2663-6, 2001 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-11551773

RESUMO

We synthesized diaminobutane derivatives as potent Ca(2+)-permeable AMPA receptor antagonists with non-hypotensive activity. Compound 10c showed selective Ca(2+)-permeable AMPA receptor antagonist activity and neuroprotective effects in transient global ischemia models in gerbils.


Assuntos
Cálcio/metabolismo , Fármacos Neuroprotetores/síntese química , Putrescina/síntese química , Receptores de AMPA/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Gerbillinae , Isquemia/prevenção & controle , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Putrescina/química , Putrescina/farmacologia , Putrescina/uso terapêutico , Receptores de AMPA/metabolismo
20.
Eur J Neurol ; 8(5): 483-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11554914

RESUMO

To examine the current emergency referral and care for acute stroke at a Japanese tertiary emergency hospital with a 24-h stroke team and care unit, we surveyed the presentations of patients with acute ischemic stroke or transient ischemic attack (TIA) seen within 7 days of onset. Delay from symptom onset to arrival at our hospital, from arrival to initial diagnostic brain computed tomography (CT), and the type of anti-thrombotic treatments were evaluated. During the 18-month period, there were 254 ischemic events in 244 patients; 239 (94%) had an ischemic stroke and 15 (6%) TIA. Eighty-two (32%) events presented within 3 h of onset, and 102 (40%) and 179 (70%) within the first 6 and 24 h, respectively. The median delay from hospital arrival to CT was 32 min, ranging 10 min to 22 h. Two hundred (79%) events underwent CT within 1 h of arrival (n=172) or at the referral hospitals before transfer (n=28). Direct ambulance transportation and more severe neurological deficits were independent predictors both for early arrival and short in-hospital delay to CT. Anti-thrombotic therapies including anticoagulant and/or antiplatelet medications were given in 237 (93%) episodes. Two (1%) patients received thrombolysis, although 18 (7%) patients fulfilled the National Institute of Neurological Disorders and Stroke guidelines for intravenous thrombolysis with tissue plasminogen activator. As in western communities, our pre-hospital emergency referral systems for acute stroke require substantial improvements including the wider use of ambulance calling. Although our in-hospital stroke management is functioning relatively well, further efforts are necessary in reducing the diagnostic delay.


Assuntos
Serviço Hospitalar de Emergência , Encaminhamento e Consulta/estatística & dados numéricos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Doença Aguda , Idoso , Serviços Médicos de Emergência , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Japão/epidemiologia , Masculino , Prognóstico , Análise de Regressão , Acidente Vascular Cerebral/tratamento farmacológico
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