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2.
Nat Commun ; 12(1): 2679, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976145

RESUMO

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1µm) over a large field of view (>1 mm2). After the evolution of a Rayleigh-Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations.

3.
Phys Rev Lett ; 126(1): 015703, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480771

RESUMO

We present results from the SPring-8 Angstrom Compact free electron LAser facility, where we used a high intensity (∼10^{20} W/cm^{2}) x-ray pump x-ray probe scheme to observe changes in the ionic structure of silicon induced by x-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in diffuse scattering and a transition to a disordered, liquidlike state with a structure significantly different from liquid silicon. The disordering occurs within 100 fs of irradiation, a timescale that agrees well with first principles simulations, and is faster than that predicted by purely inertial behavior, suggesting that both the phase change and disordered state reached are dominated by Coulomb forces. This method is capable of observing liquid scattering without masking signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change.

4.
Enzyme Microb Technol ; 52(1): 38-43, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23199737

RESUMO

Bacterial genes for the degradation of major dilignols produced in lignifying xylem are expected to be useful tools for the structural modification of lignin in plants. For this purpose, we isolated pinZ involved in the conversion of pinoresinol from Sphingobium sp. strain SYK-6. pinZ showed 43-77% identity at amino acid level with bacterial NmrA-like proteins of unknown function, a subgroup of atypical short chain dehydrogenases/reductases, but revealed only 15-21% identity with plant pinoresinol/lariciresinol reductases. PinZ completely converted racemic pinoresinol to lariciresinol, showing a specific activity of 46±3 U/mg in the presence of NADPH at 30°C. In contrast, the activity for lariciresinol was negligible. This substrate preference is similar to a pinoresinol reductase, AtPrR1, of Arabidopsis thaliana; however, the specific activity of PinZ toward (±)-pinoresinol was significantly higher than that of AtPrR1. The role of pinZ and a pinZ ortholog of Novosphingobium aromaticivorans DSM 12444 were also characterized.


Assuntos
Proteínas de Bactérias/genética , Furanos/metabolismo , Genes Bacterianos , Lignanas/metabolismo , Oxirredutases/genética , Sphingomonadaceae/genética , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Bactérias/metabolismo , Lignina/metabolismo , Estrutura Molecular , Oxirredutases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Sphingomonadaceae/enzimologia , Especificidade por Substrato
5.
Eur J Surg Oncol ; 38(11): 1101-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22863303

RESUMO

AIMS: The objectives of this study were to investigate the clinical and oncological outcomes of patients with malignant tumors of the urinary bladder undergoing minimum incision endoscopic radical cystectomy (MIE-RC). METHODS: Between August 2005 and June 2011, 130 consecutive patients at Hirosaki University Hospital underwent MIE-RC and bilateral lymphadenectomy for malignant tumors of the urinary bladder. We retrospectively studied all 130 patients. MIE-RC was performed through a 7-cm suprapubic midline incision. A 30° laparoscope was conveniently positioned on the head side of the patients, for precise observation and monitoring. RESULTS: The median operative time for all procedures, including MIE-RC, bilateral pelvic lymphadenectomy and urinary diversion was 266 min. The median estimated blood loss was 1260 mL. None of the patients had positive surgical margins. The post-operative median follow-up period was 32.8 months. The 5-year overall and disease-free survival rates were 91.6% and 87.0%, respectively. CONCLUSIONS: Our experience with MIE-RC appears to be favorable with acceptable operative and oncological outcomes.


Assuntos
Cistectomia/métodos , Laparoscopia/métodos , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistectomia/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade , Derivação Urinária
6.
Prostate Cancer Prostatic Dis ; 15(4): 397-401, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22890389

RESUMO

BACKGROUND: Radical prostatectomy (RP) has limited cancer control potential for the patient with high-risk prostate cancer (Pca). We prospectively examined the efficacy and safety of neoadjuvant therapy with luteinizing hormone-releasing hormone (LHRH) agonist + low-dose estramustine phosphate (EMP) (LHRH+EMP) followed by RP. METHODS: High-risk Pca was defined by the D'Amico stratification system. A total of 142 patients with high-risk Pca were enrolled in this trial from September 2005 to March 2011. The LHRH+EMP therapy included administration of LHRH agonist and 280 mg day(-1) EMP for 6 months before RP. Pathological cancer-free (pT0) rate on the surgical specimen was the primary end point. Secondary end points were PSA-free survival and toxicity. RESULTS: The average patient age was 67.4 years (interquartile range (IQR) 72, 65) and the median initial PSA level was 14.80 ng ml(-1) (IQR 26.22, 7.13). The median Gleason score was 9 (IQR 9, 7) and 97 patients (68.3%) had clinical stage T2c or T3. All patients completed 6 months of LHRH+EMP neoadjuvant therapy with no delays in RP. Seven patients (4.9%) achieved pT0. Surgical margins were negative in 125 patients (87.0%). At a median follow-up period of 34.9 months, PSA-free survival was 84.3%. No serious adverse events were reported during the study and there were no toxicity-related deaths. CONCLUSIONS: Six months of LHRH+EMP neoadjuvant therapy followed by RP is safe and oncological outcomes are acceptable. Although this study was a single-arm trial with a relatively short follow-up, this treatment may have a potential to improve PSA-free survival in high-risk Pca patients. Further clinical trials are warranted.


Assuntos
Estramustina/administração & dosagem , Hormônio Liberador de Gonadotropina/administração & dosagem , Terapia Neoadjuvante , Neoplasias da Próstata , Idoso , Antineoplásicos Hormonais/administração & dosagem , Relação Dose-Resposta a Droga , Seguimentos , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
7.
Eur J Surg Oncol ; 37(9): 805-10, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21782374

RESUMO

AIMS: The objective of this study was to investigate the clinical and oncological outcomes of prostatectomy patients undergoing minimum incision endoscopic radical prostatectomy (MIE-RP). METHODS: Between September 2005 and May 2010, 541 patients underwent MIE-RP with bilateral lymphadenectomy for clinically localized prostate cancer at Hirosaki University Hospital. The present retrospective study enrolled 375 patients who had not received neoadjuvant or adjuvant therapy. MIE-RP was performed through a 6-cm suprapubic midline incision. A 30° laparoscope was conveniently positioned on the head side of the patient for precise observation and monitoring. RESULTS: The median operating time was 119 min, and the estimated blood loss was 900 ml. The most frequent perioperative complication was leakage from the vesicourethral anastomosis (6.7%), and rectal injury occurred in 1.0%. Overall, 31.2% of the patients had a positive surgical margin, including 11.1% with pT2, 52.9% with pT3 and 100% with pT4 diseases. The post-operative median follow-up period was 40.5 months (range, 2-56.5 months). The 5-year PSA-free survival rate was 71.6%. In multivariate analysis, high-risk patients (according to the D'Amico risk criteria), pathological T stage and positive surgical margins were identified as independent predictors of PSA-free survival. The limitations of this study included a retrospective study, relatively short follow-up period and single-institution nature of the study. CONCLUSIONS: MIE-RP is a safe and minimally invasive procedure that may represent a reliable alternative to laparoscopic and robotic-assisted RP.


Assuntos
Endoscopia , Prostatectomia , Neoplasias da Próstata/cirurgia , Idoso , Intervalo Livre de Doença , Humanos , Laparoscopia , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Prostatectomia/métodos , Neoplasias da Próstata/mortalidade , Robótica , Taxa de Sobrevida
8.
Oncogene ; 25(40): 5581-90, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16785998

RESUMO

Genomic amplification of oncogenes and inactivation of suppressor genes are critical in the pathogenesis of human cancer. To identify chromosomal alterations associated with hepatocarcinogenesis, we performed allelic gene dosage analysis on 36 hepatocellular carcinomas (HCCs). Data from high-density single-nucleotide polymorphism arrays were analysed using the Genome Imbalance Map (GIM) algorithm, which simultaneously detects DNA copy number alterations and loss of heterozygosity (LOH) events. Genome Imbalance Map analysis identified allelic imbalance regions, including uniparental disomy, and predicted the coexistence of a heterozygous population of cancer cells. We observed that gains of 1q, 5p, 5q, 6p, 7q, 8q, 17q and 20q, and LOH of 1p, 4q, 6q, 8p, 10q, 13q, 16p, 16q and 17p were significantly associated with HCC. On 6q24-25, which contains imprinting gene clusters, we observed reduced levels of PLAGL1 expression owing to loss of the unmethylated allele. Finally, we integrated the copy number data with gene expression intensity, and found that genome dosage is correlated with alteration in gene expression. These observations indicated that high-resolution GIM analysis can accurately determine the localizations of genomic regions with allelic imbalance, and when integrated with epigenetic information, a mechanistic basis for inactivation of a tumor suppressor gene in HCC was elucidated.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Genômica , Cariotipagem , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Algoritmos , Epigênese Genética , Humanos , Hibridização in Situ Fluorescente , Perda de Heterozigosidade , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos
10.
Mol Pharmacol ; 58(6): 1368-74, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11093775

RESUMO

Regulation of the kinetics of intracellular Ca(2+) signals with a novel, membrane-penetrable, inositol 1,4,5-trisphosphate (InsP(3)) receptor/Ca(2+) channel modulator, 2-amino-ethoxydiphenyl borate (2APB), has been investigated using patch-clamp, whole-cell recording to monitor Ca(2+)-activated Cl(-) currents in single isolated pancreatic acinar cells. 2APB itself fails to evoke a detectable current response but it dramatically changes the kinetics of agonist-induced Ca(2+) release from pulsatile spikes to long-lasting, huge Ca(2+) waves, suggesting that 2APB coordinates local Ca(2+) release to generate global Ca(2+) signals. The regulation by 2APB can be elicited by internal perfusion of InsP(3) in a concentration-dependent manner, indicating that this regulation is not mediated through membrane receptors or G protein signal transduction. The InsP(3) receptor blocker heparin, but not the ryanodine-sensitive receptor blockers ruthenium red or ryanodine, abolishes 2APB-mediated regulation of Ca(2+) release. This results also suggest that 2APB effects are mediated through InsP(3) receptors. 2APB substantially modifies single inward Cl(-) current pulse evoked by the photolytic release of caged InsP(3) but not by caged Ca(2+). These data indicate that 2APB-induced regulation is mediated neither by Ca(2+)-induced Ca(2+) release nor by affecting Cl(-) channel activity directly. We conclude that 2APB regulates the kinetics of intracellular Ca(2+) signals, represented as the change in the Ca(2+) oscillation patterns from brief pulsatile spikes to huge, long-lasting Ca(2+) waves. Moreover, this regulation seems to be mediated through InsP(3)-sensitive Ca(2+) pools. 2APB may act as a novel, useful pharmacological tool to study the genesis of intracellular Ca(2+) signals.


Assuntos
Compostos de Boro/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Inositol 1,4,5-Trifosfato/metabolismo , Pâncreas/efeitos dos fármacos , Animais , Sinalização do Cálcio/fisiologia , Técnicas In Vitro , Cinética , Camundongos , Pâncreas/citologia , Pâncreas/metabolismo , Técnicas de Patch-Clamp
11.
J Neurol Sci ; 177(2): 150-3, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10980312

RESUMO

A female patient who fulfilled the diagnostic criteria of Walker-Warburg syndrome had muscle biopsy finding of muscular dystrophy. There was normal expression of merosin (laminin alpha2 chain) and dystrophin and only slightly reduced dystrophin-associated glycoprotein expression. On genetic analysis, she had no specific haplotype, the common mutation of 3kb insertion, or point mutations in the Fukuyama-type congenital muscular dystrophy gene, suggesting that the two diseases are not genetically identical.


Assuntos
Encéfalo/anormalidades , Distrofias Musculares/genética , Alelos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Face/anormalidades , Feminino , Humanos , Imuno-Histoquímica , Lactente , Músculos/patologia , Distrofias Musculares/diagnóstico por imagem , Distrofias Musculares/patologia , Mutação , Linhagem , Radiografia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome
12.
Pflugers Arch ; 440(4): 566-72, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10958340

RESUMO

Using the patch-clamp method, we studied the mechanism of depolarization of rat pancreatic beta-cells induced by glucagon-like peptide 1 (7-36) amide (GLP-1). GLP-1 caused depolarization in a concentration-dependent manner (0.2-100 nM). Exendin (9-39) amide, a GLP-1 receptor antagonist, prevented the GLP-1-induced depolarization. GLP-1 reduced tolbutamide-sensitive membrane currents evoked by voltage ramps from -90 to -50 mV, recorded in the perforated whole-cell configuration, suggesting that GLP-1 decreased the activity of the ATP-sensitive K+ channel (KATP). This GLP-1 effect was prevented by exendin (9-39) amide. In cells treated with Rp-cAMPS, an inhibitor of the cAMP-dependent protein kinase (PKA), GLP-1 still caused depolarization and reduced the whole-cell membrane current through KATP. Examined in the cell-attached configuration, 20 nM GLP-1, applied out of the patch, had little effect on KATP activity. In the inside-out configuration, the open time probability and the single-channel conductance of KATP in the absence of ATP inside the membrane were unaffected by the presence of 20 nM GLP-1 in the pipette. In both conditions, application of ATP to the inside of the membrane reduced KATP activity. The half-maximal concentrations (ki) of ATP were 11.6 microM without and 5.6 microM with 20 nM GLP-1 in the pipette (P<0.05). The values of the Hill coefficient (h) were 1.03 without and 1.01 with GLP-1. We conclude that GLP-1 reduces KATP activity by elevating the sensitivity of KATP to ATP, resulting in depolarization of pancreatic beta-cells. This GLP-1 action is independent of the cAMP signalling pathway.


Assuntos
Trifosfato de Adenosina/farmacologia , AMP Cíclico/farmacologia , Glucagon/farmacologia , Ilhotas Pancreáticas/fisiologia , Fragmentos de Peptídeos/farmacologia , Canais de Potássio/fisiologia , Precursores de Proteínas/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Condutividade Elétrica , Peptídeo 1 Semelhante ao Glucagon , Masculino , Potenciais da Membrana/efeitos dos fármacos , Canais de Potássio/efeitos dos fármacos , Ratos , Ratos Wistar
13.
Exp Physiol ; 85(1): 37-42, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10662890

RESUMO

Ionic mechanisms and signal transduction underlying noradrenaline (NA)-induced depolarization in single smooth muscle cells of guinea-pig vas deferens were studied. NA caused depolarization followed by action potentials through activation of 1-adrenoceptors. In the presence of nifedipine, no action potential was generated, and the magnitude of the depolarization depended on the concentration of NA (0.1-100 micrometer). NA, through 1-adrenoceptor activation, reduced the magnitude of membrane currents in response to voltage ramp pulses from -90 to -30 mV in a concentration-dependent manner. The reversal potential of the current inhibited by NA changed proportionally to the change in the equilibrium potential of K+, suggesting that NA inhibited K+ channel activity. Treatment of cells with GDPS, an inhibitor of G proteins, or bisindolylmaleimide (BIM), a selective protein kinase C (PKC) inhibitor, prevented the NA inhibition of the currents. Application of 12-O-tetradecanoylphorbol 13-acetate (TPA), an activator of PKC, mimicked the effect of NA. It is suggested that in the smooth muscle of guinea-pig vas deferens, activation of 1-adrenoceptors and the subsequent activation of PKC led to inhibition of K+ currents, which is responsible for the depolarization induced by NA.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Músculo Liso/efeitos dos fármacos , Norepinefrina/farmacologia , Bloqueadores dos Canais de Potássio , Proteína Quinase C/fisiologia , Ducto Deferente/efeitos dos fármacos , Animais , Separação Celular , Eletrofisiologia , Cobaias , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Músculo Liso/citologia , Técnicas de Patch-Clamp , Transdução de Sinais/efeitos dos fármacos , Ducto Deferente/citologia
14.
Cell Signal ; 12(1): 63-70, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10676849

RESUMO

We investigated the effect of intracellular cAMP on the gating kinetics of L-type Ca2+ channel in an A7r5 smooth muscle-derived cell line using the whole-cell patch-clamp technique. Application of dibutyryl cyclic AMP (db-cAMP) to the cell increased the magnitude of Ca2+ currents through L-type Ca2+ channels (I(Ca)), and shifted the current-voltage relationship (I-V curve) for I(Ca) to the left. The magnitudes of maximum I(Ca) were 14.1 +/- 0.7 before and 16.0 +/- 1.1 pA/pF after application of 1 mM db-cAMP (P < 0.05). The values of the half-activation potential (V(1/2)) of I(Ca), estimated from activation curves, were -7.0 +/- 0.8 mV before and -10.8 +/- 1.0 mV after application of db-cAMP (P < 0.05). In cells pretreated with 10 microM Rp-cAMPS (a specific inhibitor of PKA), db-cAMP affected neither the I-V curve nor the activation curve for I(Ca). In cells pretreated with the antisense oligonucleotide for the beta-subunit of L-type Ca2+ channel, db-cAMP failed to enhance I(Ca) or alter the activation curve. On the other hand, in the cells pretreated with the nonsense oligonucleotide, application of db-cAMP caused an increase in magnitude of I(Ca) and shifted the activation curve to the left. Western blot analysis revealed that the pretreatment of cells with antisense oligonucleotide but nonsense oligonucleotide reduced the expression of the beta-subunit of the L-type Ca2+ channel. We conclude that the cAMP-dependent phosphorylation of the beta-subunit potentiates the voltage dependency of the activation kinetics of the L-type Ca2+ channel in A7r5 cells.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Músculo Liso Vascular/metabolismo , Transdução de Sinais , Animais , Linhagem Celular , AMP Cíclico/metabolismo , Ativação do Canal Iônico , Fosforilação , Ratos
15.
J Biol Chem ; 274(48): 34059-66, 1999 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-10567373

RESUMO

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is a neonatal disease characterized by dysregulation of insulin secretion accompanied by profound hypoglycemia. We have discovered that islet cells, isolated from the pancreas of a PHHI patient, proliferate in culture while maintaining a beta cell-like phenotype. The PHHI-derived cell line (NES2Y) exhibits insulin secretory characteristics typical of islet cells derived from these patients, i.e. they have no K(ATP) channel activity and as a consequence secrete insulin at constitutively high levels in the absence of glucose. In addition, they exhibit impaired expression of the homeodomain transcription factor PDX1, which is a key component of the signaling pathway linking nutrient metabolism to the regulation of insulin gene expression. To repair these defects NES2Y cells were triple-transfected with cDNAs encoding the two components of the K(ATP) channel (SUR1 and Kir6.2) and PDX1. One selected clonal cell line (NISK9) had normal K(ATP) channel activity, and as a result of changes in intracellular Ca(2+) homeostasis ([Ca(2+)](i)) secreted insulin within the physiological range of glucose concentrations. This approach to engineering PHHI-derived islet cells may be of use in gene therapy for PHHI and in cell engineering techniques for administering insulin for the treatment of diabetes mellitus.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Glucose/farmacologia , Proteínas de Homeodomínio , Hiperinsulinismo/genética , Hipoglicemia/genética , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Canais de Potássio Corretores do Fluxo de Internalização , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Eletrofisiologia , Engenharia Genética , Humanos , Hiperinsulinismo/patologia , Hipoglicemia/patologia , Lactente , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Canais de Potássio/genética , Cloreto de Potássio/farmacologia , Receptores de Droga/genética , Proteínas Recombinantes de Fusão/genética , Receptores de Sulfonilureias , Tolbutamida/farmacologia , Transativadores/genética , Transfecção , Células Tumorais Cultivadas
16.
Epilepsia ; 40(9): 1269-78, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10487191

RESUMO

PURPOSE: To clarify the relation between quantitative electroencephalogram (EEG) findings and outcome following corpus callosotomy (CC). METHODS: The degree of bilateral synchrony and morphologic similarity of spike-wave discharges was analyzed by using a cross-correlation analysis and the measurements of amplitude differences between bilateral homologous regions in 22 patients who underwent anterior CCs for intractable symptomatic generalized epilepsies (SGE; 17 patients) and frontal lobe epilepsy (five patients). RESULTS: Interictal generalized synchronous spike-wave (GSSW) bursts in the SGE patients were disrupted and changed to unilateral spike-waves (USWs) in 11 patients and to bilaterally independent spike-waves (BISWs) in six. The USW group had better surgical outcome than the BISW group. Preoperatively, the USW group had significantly lower interhemispheric synchrony (IS) and fewer regional changes in the side leading in time and the side dominant for amplitude, suggesting unilaterally predominant epileptogenesis that triggered the secondary bilateral synchrony. Postoperatively, the BISW group had a more marked reduction in IS because of independent discharges from bilateral epileptogenic areas, and the USW group had a greater amplitude difference because of unilateralized spike-waves. In addition, an excellent surgical outcome was related to (a) the preoperative degree of the morphologic similarity of the bilateral spike-waves (only a small variation during a burst of spike-waves) and the few instances of regional changes in the side leading in time and in the side dominant for amplitude; and (b) to large postoperative amplitude differences. CONCLUSION: Preoperative quantitative EEG analyses enabled us to predict the underlying conditions of epileptogenesis and the surgical outcomes in patients undergoing CC.


Assuntos
Córtex Cerebral/fisiopatologia , Corpo Caloso/cirurgia , Eletroencefalografia/estatística & dados numéricos , Epilepsia Generalizada/fisiopatologia , Epilepsia Generalizada/cirurgia , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Seguimentos , Lateralidade Funcional/fisiologia , Humanos , Probabilidade , Resultado do Tratamento
17.
Diabetes ; 48(9): 1741-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10480603

RESUMO

The effects of corticotropin-releasing factor (CRF) on the intracellular concentration of Ca2+ were studied in isolated single beta-cells of the rat islet. Immunohistochemical staining using CRF-receptor antibodies revealed the presence of both type 1 (CRF-R1) and type 2 (CRF-R2) receptors for CRF in the majority of islet cells. CRF (2 nmol/l) increased cytosolic Ca2+ concentration under 2.8 mmol/l glucose, dependent upon extracellular Ca2+. CRF caused depolarization of the cell membrane, which was followed by action potentials under 2.8 mmol/l glucose. The dose-response relationships of CRF-induced depolarization in the presence of 1 micromol/l nifedipine produced a bell-shaped curve, showing the peak response at 2 nmol/l. In the whole-cell patch-clamp recording, CRF enhanced Ca2+ currents through L-type Ca2+ channels in a dose-dependent manner similar to that for depolarization. In cells pretreated with Rp-deastereomer of adenosine cyclic 3',5'-phosphorothiolate (100 micromol/l), neither depolarization nor an increase in the Ca2+ current was caused by CRF at concentrations <2 nmol/l. In these cells, CRF at 20 nmol/l reduced the Ca2+ current. These results suggest that in single beta-cells of rat islets, CRF, through its own receptor, potentiates Ca2+ influx through the L-type Ca2+ channel by activation of the cAMP/protein kinase A signaling pathway. CRF at a high concentration also shows an inhibitory effect on the Ca2+ current through an unknown signaling pathway.


Assuntos
Cálcio/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Animais , Imuno-Histoquímica , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Transdução de Sinais/efeitos dos fármacos
19.
J Hum Genet ; 43(1): 62-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9610001

RESUMO

We report the case of a Japanese girl with a severe type of Moebius syndrome. Her morphological features were a mask-like face, limitation of horizontal eye movements, severe bulbar palsy, multiple and bilateral arthrogryposis including the elbow, knee, and ankle joints, and clubfeet. After birth, her general condition became worse because of repeated apneic spells and aspiration pneumonias due to dysphagia. She finally required tracheotomy. Computed tomography (CT) of the brain revealed minute calcifications on the fourth ventricle floor; this may have been due to severe damage to the brain stem. It is most likely that the various manifestations in our patient were due to disturbance of the blood supply to arteries perfusing the brain stem and to some other arteries, at a critical stage of fetal development.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Anormalidades Múltiplas/embriologia , Tronco Encefálico/anormalidades , Tronco Encefálico/irrigação sanguínea , Feminino , Humanos , Lactente , Artéria Subclávia/anormalidades , Síndrome , Tomografia Computadorizada por Raios X
20.
Cell Signal ; 9(5): 367-72, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9376216

RESUMO

The whole-cell patch-clamp method was used on A7r5 smooth muscle-derived cell line, and Ba2+ currents through Ca2+ channels were recorded. The A7r5 cells showed voltage-dependent, long-lasting Ba2+ currents which were markedly inhibited by nifedipine (10 microM). The magnitude of the maximum Ba2+ current (IBa(max)) was augmented by an application of dbcAMP (1 mM), but not affected by TPA (80 nM). Noradrenaline (NA) at 100 microM caused an increase in the IBa(max) by 19.7% in the presence of phentolamine (10 microM). This effect was cancelled by Rp-cAMPs (10 microM). In the presence of propranolol (10 microM), NA tended to reduce the IBa(max). Application of Ox-LDLs at 100 microg protein/ml caused an increase in the IBa(max) by 15.7%, whereas native LDLs did not change the IBa(max). Rp-cAMPs was ineffective to the Ox-LDL action on the IBa(max). In the presence of Ox-LDLs, NA augmented the IBa(max) by 21.4% in the presence of phentolamine. These results suggest that Ox-LDLs activate L-type Ca2+ channels of A7r5 cells by a mechanism independent of cAMP/PKA signalling.


Assuntos
Bário/metabolismo , Canais de Cálcio/metabolismo , Lipoproteínas LDL/metabolismo , Músculo Liso Vascular/metabolismo , Aorta/citologia , Aorta/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular , Cromatografia em Camada Fina , Humanos , Potenciais da Membrana , Músculo Liso Vascular/citologia , Nifedipino/farmacologia , Norepinefrina/farmacologia , Técnicas de Patch-Clamp , Vasoconstritores/farmacologia
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