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1.
J Neurosci ; 42(46): 8621-8628, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36180227

RESUMO

Recent connectome analyses of the entire synaptic circuit in the nervous system have provided tremendous insights into how neural processing occurs through the synaptic relay of neural information. Conversely, the extent to which ephaptic transmission which does not depend on the synapses contributes to the relay of neural information, especially beyond a distance between adjacent neurons and to neural processing remains unclear. We show that ephaptic transmission mediated by extracellular potential changes in female Drosophila melanogaster can reach >200 µm, equivalent to the depth of its brain. Furthermore, ephaptic transmission driven by retinal photoreceptor cells mediates light-evoked firing rate increases in olfactory sensory neurons. These results indicate that ephaptic transmission contributes to sensory responses that can change momentarily in a context-dependent manner.SIGNIFICANCE STATEMENT Although extracellular field potential activities are commonly observed in many nervous systems, this activity has been generally considered as a side effect of synchronized spiking of neurons. This study, however, shows that field potential changes in retinae evoked by a sensory stimulus can control the excitability of distant neurons in vivo and mediates multimodal sensory integration in Drosophila melanogaster As such ephaptic transmission is more effective at a short distance, the ephaptic transmission from the retinae may contribute significantly to firing rate changes in downstream neurons of the photoreceptor cells in the optic lobe.


Assuntos
Drosophila melanogaster , Neurônios Receptores Olfatórios , Animais , Feminino , Drosophila melanogaster/fisiologia , Odorantes , Neurônios Receptores Olfatórios/fisiologia , Sinapses/fisiologia , Encéfalo/fisiologia , Transmissão Sináptica/fisiologia
2.
Zoolog Sci ; 40(6): 423-430, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38064368

RESUMO

In diurnal and nocturnal organisms, daily activity is regulated by the perception of environmental stimuli and circadian rhythms, which enable organisms to maintain their essential behaviors. The Japanese sand lances genus Ammodytes are coastal marine fish that exhibit unique nocturnal sand burrowing behavior. To elucidate the extrinsic and intrinsic regulation of this behavior and its endocrinological basis, we conducted a series of rearing experiments under various light conditions and hormone administrations. Under a light-dark photoperiod, the fish showed three types of behavior: sand buried, head-exposed from sand, and swimming/feeding. During the transition from dark to light periods, the fish first showed head exposure, followed by swimming and foraging, and buried themselves in the sand immediately after shifting to the dark period. Under constant light conditions, fish exhibited swimming behavior during the period corresponding to the acclimated light period. In addition, swimming did not occur under constant dark conditions but head exposure was observed at the time of the dark-light transition during acclimation. These observations indicate that the essential behavior of sand lances is regulated by both light and circadian rhythms. Subsequently, a melatonin-containing diet promoted the onset of burrowing in 10 to 120 min in a dose-dependent manner at 0.3-128 µg/g-diet, suggesting the direct behavioral regulation by this hormone. These findings suggest that the behavior of sand lances is strictly regulated by an intrinsic mechanism and that melatonin is a regulatory endocrine factor that induces burrowing behavior.


Assuntos
Melatonina , Perciformes , Animais , Natação , Melatonina/farmacologia , Japão , Ritmo Circadiano/fisiologia , Fotoperíodo , Luz
3.
Gan To Kagaku Ryoho ; 47(4): 712-714, 2020 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-32389993

RESUMO

A 60-year-old woman was referred to our hospital due to pancreatic head cancer with right ureter invasion. We considered that it was difficult to achieve R0 resection for the patient by operation because of a wide range of retroperitoneal invasions involving the right ureter. She was treated with chemotherapy(gemcitabine plus nab-paclitaxel: GnP). GnP therapy was administered 3-weeks on/1-week off for 1 course. After 3 courses, we performed pancreaticoduodenectomy, right nephrectomy and partial transverse colectomy. We achieved R0 resection and considered the GnP therapy to be effective.


Assuntos
Neoplasias Pancreáticas , Ureter , Protocolos de Quimioterapia Combinada Antineoplásica , Desoxicitidina , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia
4.
Biochem Biophys Res Commun ; 515(1): 248-253, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31146915

RESUMO

The soluble epoxide hydrolase (sEH) is a bifunctional enzyme implicated in the regulation of inflammation. The N-terminal domain harbors a phosphatase activity (N-phos) with an affinity to lipid phosphomonoesters, and the C-terminal domain has an activity to hydrolyze anti-inflammatory lipid epoxides (C-EH). Although many potent inhibitors of C-EH have been discovered, little is known about inhibitors of N-phos. Here, we identify N-substituted amino acids as selective inhibitors of N-phos. Many of the N-substituted amino acids inhibited differently mouse and human N-phos; phenylalanine derivatives are relatively selective for mouse N-phos, whereas tyrosine derivatives are more selective for human N-phos. The best inhibitors, Fmoc-l-Phe(4-CN) (67) and Boc-l-Tyr(Bzl) (23), inhibited mouse and human N-phos competitively with KI in the low micromolar range. These compounds inhibit the N-phos activity 37- (67) and 137-folds (23) more potently than the C-EH. The differences in inhibitor structure activity suggest different active site structure between species, and thus, probably a divergent substrate preference between mouse and human N-phos.


Assuntos
Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Substituição de Aminoácidos , Animais , Sítios de Ligação/genética , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Epóxido Hidrolases/genética , Epóxido Hidrolases/metabolismo , Compostos de Epóxi/metabolismo , Humanos , Hidrólise/efeitos dos fármacos , Cinética , Camundongos , Fenilalanina/química , Fenilalanina/genética , Fenilalanina/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Solubilidade , Especificidade da Espécie , Tirosina/química , Tirosina/genética , Tirosina/metabolismo
5.
Acta Med Okayama ; 70(6): 449-453, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28003669

RESUMO

Metastatic epidural spinal cord compression (MESCC) is a common complication in patients with a malignant tumor, but it is difficult to decide the proper time to perform the necessary surgery. Here we analyzed the prognostic factors for postoperative walking ability. We retrospectively reviewed the cases of 112 MESCC patients treated surgically at our institute and divided them into ambulatory (n= 88) and non-ambulatory (n=24) groups based on their American Spinal Injury Association (ASIA) Impairment Scale grades at the final follow-up. We also classified the patients preoperatively using the revised Tokuhashi score. We assessed the correlation between preoperative or intraoperative factors and postoperative walking ability in both groups. Of the 10 patients classified preoperatively as grade A or B, 2 (20% ) were ambulatory at the final follow-up. Of the 102 patients classified preoperatively as grade C, D or E, 86 (84% ) were ambulatory at the final follow-up (p<0.001). There were no significant differences between the groups in the average total Tokuhashi score. Our analysis revealed that the severity of paralysis significantly affects neurological recovery in patients with MESCC. Patients with MESCC should receive surgery before the preoperative ASIA Impairment Scale grade falls below grade C.


Assuntos
Descompressão Cirúrgica , Neoplasias/complicações , Compressão da Medula Espinal/etiologia , Neoplasias da Medula Espinal/complicações , Neoplasias da Medula Espinal/secundário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Compressão da Medula Espinal/cirurgia , Resultado do Tratamento , Adulto Jovem
6.
Acta Med Okayama ; 66(3): 213-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22729101

RESUMO

There are a variety of treatment options for patients with spinal metastasis, and predicting prognosis is essential for selecting the proper treatment. The purpose of the present study was to identify the significant prognostic factors for the survival of patients with spinal metastasis. We retrospectively reviewed 143 patients with spinal metastasis. The median age was 61 years. Eleven factors reported previously were analyzed using the Cox proportional hazards model:gender, age, performance status, neurological deficits, pain, type of primary tumor, metastasis to major organs, previous chemotherapy, disease-free interval before spinal metastasis, multiple spinal metastases, and extra-spinal bone metastasis. The average survival of study patients after the first visit to our clinic was 22 months. Multivariate survival analysis demonstrated that type of primary tumor (hazard ratio [HR] = 6.80, p < 0.001), metastasis to major organs (HR = 2.01, p = 0.005), disease-free interval before spinal metastasis (HR = 1.77, p = 0.028), and extra-spinal bone metastasis (HR = 1.75, p = 0.017) were significant prognostic factors. Type of primary tumor was the most powerful prognostic factor. Other prognostic factors may differ among the types of primary tumor and may also be closely associated with primary disease activity. Further analysis of factors predicting prognosis should be conducted with respect to each type of primary tumor to help accurately predict prognosis.


Assuntos
Neoplasias da Coluna Vertebral/mortalidade , Neoplasias da Coluna Vertebral/secundário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida
7.
Biochem Biophys Res Commun ; 416(3-4): 385-90, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22120635

RESUMO

XLGα(olf) is an extra large transcriptional variant of the heterotrimeric G protein, Gα(olf), which we previously reported to be localized in the Golgi apparatus and interacted with Rab3A and Rab8A through its N-terminal region. However, many physiological functions of XLGα(olf) remain to be elucidated. In this study, performance of yeast two-hybrid screening with XLGα(olf) allowed isolation of COP9 signalosome subunit 5 (CSN5), known to regulate the p27(Kip1) protein level through a proteasome dependent pathway. Co-immunoprecipitation experiments followed by Western blotting also showed association of CSN5 with XLGα(olf) linked to down-regulation of p27(Kip1). Gene silencing of endogenous CSN5 by siRNA attenuated the XLGα(olf)-mediated down-regulation, which was also demonstrated to require CDK2. Both knock down of CDK2 and the treatment with a CDK2 inhibitor reversed the reduction of p27(Kip1) due to XLGα(olf). Our findings provide important clues to understanding physiological functions of XLGα(olf).


Assuntos
Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/biossíntese , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeo Hidrolases/metabolismo , Complexo do Signalossomo COP9 , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 2 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Regulação para Baixo , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Inativação Gênica , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeo Hidrolases/genética , RNA Interferente Pequeno/genética , Técnicas do Sistema de Duplo-Híbrido
8.
Lab Chip ; 10(24): 3341-7, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20714639

RESUMO

This report describes the fabrication and characterization of a simple and disposable capillary isoelectric focusing (cIEF) device containing a reagent-release capillary (RRC) array and poly(dimethylsiloxane) (PDMS) platform, which allows rapid (within 10 min) screening of cIEF conditions by introducing a sample solution into plural RRCs by capillary action followed by electric field application. To prepare the RRC, covalent immobilization of poly(dimethylacrylamide) (PDMA) was conducted to suppress electro-osmotic flow (EOF), followed by physical adsorption of the mixture of carrier ampholyte (CA), surfactant, labeling reagent (LR), and other additives to the PDMA surface to construct a two-layer structure inside a square glass capillary. When the sample solution containing proteins was introduced into the RRC, physically adsorbed CA, surfactant, and LR can be dissolved and released into the sample solution. Then, complexation of LR with proteins, mixing with CA and surfactant, and exposure of the PDMA surface spontaneously occurs for the IEF experiments. Here, three different RRCs that immobilize different CAs were prepared, and simultaneous cIEF experiments involving hemoglobin AFSC mixtures for choosing the best CA demonstrated the proof of concept.


Assuntos
Focalização Isoelétrica/instrumentação , Focalização Isoelétrica/métodos , Acrilamidas/química , Adsorção , Animais , Soluções Tampão , Química/métodos , Dimetilpolisiloxanos/química , Eletroforese Capilar , Desenho de Equipamento , Hemoglobinas/química , Humanos , Tensoativos/química , Temperatura
9.
Acta Med Okayama ; 64(2): 109-13, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20424665

RESUMO

To assess the effects of service dogs on health-related quality of life (HRQOL), we conducted a survey of 10 service dog owners using SF-36v2 (Medical Outcomes Study 36 Item Short-Form Health Survey Version 2.0) and compared it with a matched control group of people with physical disabilities who did not have service dogs but were eligible for one. The scores for mental health and role emotional of service dog owners were relatively high, and their mental component summary was higher than the general population norm. These results indicate that service dogs affect the mentality of their owners. The comparison with the control group indicated that service dogs alleviate the mental burden of daily activities, and subjectively improved the physical functioning of their owners. This study showed that service dogs have positive functional and mental effects on their disabled owners.


Assuntos
Pessoas com Deficiência/psicologia , Cães , Vínculo Humano-Animal , Qualidade de Vida , Adulto , Idoso , Animais , Pessoas com Deficiência/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Biochem Biophys Res Commun ; 381(4): 582-6, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19245791

RESUMO

XLGalpha(olf) was identified as a transcriptional variant of the heterotrimeric G protein, Galpha(olf). Previous work showed that XLGalpha(olf) couples with adenosine A2a receptor and dopamine D1 receptor in vitro. However, physiological functions of XLGalpha(olf) remain to be elucidated. In this study, we performed indirect immunofluorescence confocal analyses to examine the subcellular localization of XLGalpha(olf). With overexpression, surprisingly, many large endosomes resulted. We also observed that XLGalpha(olf) localizes at the Golgi apparatus. The N-terminal region of XLGalpha(olf) appears necessary for both endosome formation and the Golgi localization. The results indicate that XLGalpha(olf) and Galpha(olf) play distinctly separate roles. Moreover, XLGalpha(olf) colocalized with Rab3A and Rab8A, as well as partially with Rab11A, but not with other endocytotic endosomes. We could confirm the interaction between XLGalpha(olf) and Rab3A/Rab8A by co-immunoprecipitation experiments. Our study provides important clues toward understanding physiological functions of XLGalpha(olf).


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Animais , Células COS , Núcleo Celular/enzimologia , Chlorocebus aethiops , Endossomos/enzimologia , Complexo de Golgi/enzimologia , Humanos , Proteínas rab de Ligação ao GTP/metabolismo , Proteína rab3A de Ligação ao GTP/metabolismo
11.
Acta Med Okayama ; 58(4): 189-95, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15551756

RESUMO

Muscle power in the lower extremities and body sway were measured in 57 healthy young women volunteers in their 20's. Body sway was measured with a stabilimeter for 30 sec during two-leg standing, and for 10 sec during one-leg standing with the eyes open or closed, alternating between right and left legs (5 times each). The measured parameters of body sway were locus length per time unit, locus length per environmental area, environmental area, rectangle area, root mean square area, and the ratio of sway with eyes closed to sway with eyes open. Knee flexor and extensor power and toe flexor and abductor power were the measures representing lower extremity muscle power. The increase in sway with the eyes closed was more marked during one-leg standing than two-leg standing, as expected. We found that 36 of 57 subjects (62%) were unable to maintain one-leg standing with their eyes closed, and this failure correlated with marked body sway (P = 0.0086). Many subjects had one leg that was classified as stable and the other leg classified as unstable. Clearly, testing of both legs alternately with eyes closed is necessary to measure the full range of sway in subjects. Lower extremity muscle power did not appear to be the dominant factor in maintaining balance in these young subjects.


Assuntos
Articulação do Joelho/fisiologia , Músculo Esquelético/fisiologia , Equilíbrio Postural/fisiologia , Articulação do Dedo do Pé/fisiologia , Adulto , Feminino , Humanos , Contração Muscular/fisiologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-14503661

RESUMO

(S)-9-chloro-5-[p-aminomethyl-o-(carboxymethoxy)phenylcarbamoylmethyl]-6,7-dihydro-1 H,5 H-pyrido[1,2,3-de]quinoxaline-2,3-dione hydrochloride trihydrate (SM-18400) was given intravenously to rats and dogs and its pharmacokinetics was investigated. By LC/MS/MS analysis, the major metabolite in the rat serum was identified as N-acetylated SM-18400 (SM-NAc). In rats, AUC ratio of SM-NAc to SM-18400 was approximately 50%. However, 71% of the dose was excreted as unchanged SM-18400 and only 9.8% as SM-NAc in the urine and bile, indicating that the contribution of N-acetylation clearance (CL(NAc)) to the total clearance (CL(tot)) is limited to 10-30% in rats. No SM-NAc or other metabolites were detected in the dog serum, urine or bile. The in vitro intrinsic clearance (CL(int), ml/min/mg cytosolic protein) of N-acetyltransferase (NAT) activities of dog liver cytosol towards SM-18400 and hepatic N-acetylation clearance (CL(NAc), ml/min/kg body weight) estimated by well-stirred model were both only 5% of the respective rat value, well reflecting the relative in vivo CL(NAc)/CL(tot) ratios. CL(int) values for human liver cytosol samples (n = 4) and estimated CL(NAc) were all less than 18% and 7% of the rat, respectively. Based on these results, we concluded that the CL(NAc)/CL(tot) of human would be small enough to avoid major inter-individual variance in SM-18400 pharmacokinetics due to N-acetylation polymorphism. In addition, even a human liver cytosol sample lacking polymorphic NAT2 activity as determined by sulfamethazine (SMZ) N-acetylation analysis, proved capable of acetylating SM-18400, suggesting that NAT2 is not the major enzyme responsible for N-acetylation of SM-18400 in human. This fact would also reduce the risk of N-acetylation polymorphism playing a role in clinical use of this drug.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacocinética , Quinoxalinas/farmacocinética , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Acetilação , Acetiltransferases/metabolismo , Animais , Área Sob a Curva , Biotransformação , Cromatografia Líquida de Alta Pressão , Citosol/metabolismo , Cães , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Cinética , Fígado/metabolismo , Masculino , Polimorfismo Genético , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray , Frações Subcelulares/metabolismo
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