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1.
Rev Sci Instrum ; 94(1): 013502, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725594

RESUMO

A three-color laser interferometer consisting of three Mach-Zehnder-type, one-color laser interferometers with heterodyne detection and coaxial laser beams is demonstrated. The three-color laser interferometer is considered as three sets of a two-color laser interferometer. From the two sets of the two-color laser interferometer, the value consisting only of the noise floor can be assessed. The noise floor can be reduced by subtracting the value consisting only of the noise floor from the measurement value obtained with the other two-color laser interferometer. In the case of the three lasers with wavelengths 9.25 µm, 10.59 µm, and 532 nm, a 15% noise reduction was obtained compared to the two sets of the two-color laser interferometers contained in the three-color laser interferometer. The 100-Hz noise reduction by 53% was achieved, and the other frequency noises were equal to or less than the smallest noise achieved by the two-color laser interferometers. The 100-Hz noise floor is caused by the vibration noise, which remains because of the non-coaxiality of the three beams.

2.
Sci Rep ; 10(1): 5, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913300

RESUMO

When realising future fusion reactors, their stationary burning must be maintained and the heat flux to the divertor must be reduced. This essentially requires a stationary internal transport barrier (ITB) plasma with a fast control system. However, the time scale for determining the position of the foot point of an ITB is not clearly understood even though its understanding is indispensable for fast profile control. In this study, the foot point of the electron ITB (eITB) was observed to be reformed at the vicinity of a magnetic island when the island started to form. In addition, the enhanced confinement region was observed to expand during the eITB formation according to the radial movement of the magnetic island toward the outer region. Compared to the time scales of the local heat transport, the faster time scales of the movement of the eITB foot point immediately after island formation (~0.5 ms) suggest the importance of the magnetic island for plasma profile control to maintain stationary burning.

3.
Rev Sci Instrum ; 89(10): 10B104, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399925

RESUMO

A thermal image plate (TIP) using ceramic luminescence materials has been developed in order to visualize a beam spot of a CO2 laser which is used as a light source of an interferometer developed in JT-60SA. By using CaAlSiN3:Eu2+ (CASN), the TIP was developed, and its property was assessed. A CASN TIP was able to visualize the invisible CO2 laser beam as a negative image. The beam diameter and the stability of the beam axis measurement obtained with the CASN TIP were approximately the same as that obtained with a commercial TIP. Furthermore, the time response of the CASN TIP at the best was approximately the same as that of the commercial TIP. The CASN TIP which had the highest time response was applied to the beam axis stabilizer, and then the beam axis stabilization was successfully performed in 2 h.

4.
Rev Sci Instrum ; 87(11): 11D818, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910618

RESUMO

A Faraday-cup type lost-fast ion probe (FLIP) has been designed and installed in Heliotron J for the purpose of the studies of interaction between fast ions and MHD instabilities. The FLIP can measure the co-going fast ions whose energy is in the range of 1.7-42.5 keV (proton) and pitch angle of 90∘-140∘, especially for fast ions having the injection energy of neutral beam injection (NBI). The FLIP successfully measured the re-entering passing ions and trapped lost-fast ions caused by fast-ion-driven energetic particle modes in NBI heated plasmas.

5.
Mol Psychiatry ; 21(10): 1449-59, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26728564

RESUMO

Exploring drug targets based on disease-associated molecular mechanisms during development is crucial for the generation of novel prevention and treatment strategies for neurodevelopmental psychiatric conditions. We report that prefrontal cortex (PFC)-specific postnatal knockdown of DISC1 via in utero electroporation combined with an inducible knockdown expression system drives deficits in synaptic GABAA function and dendritic development in pyramidal neurons, as well as abnormalities in sensorimotor gating, albeit without profound memory deficits. We show for the first time that DISC1 is specifically involved in regulating cell surface expression of α2 subunit-containing GABAA receptors in immature developing neurons, but not after full maturation. Notably, pharmacological intervention with α2/3 subtype-selective GABAA receptor positive allosteric modulators during the early postnatal period ameliorates dendritic deficits and behavioral abnormalities induced by knockdown of DISC1. These findings highlight a critical role of DISC1-mediated disruption of postnatal GABA signaling in aberrant PFC maturation and function.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Animais , Modelos Animais de Doenças , Eletroporação , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/efeitos dos fármacos , Proteínas do Tecido Nervoso/fisiologia , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Subunidades Proteicas , Células Piramidais/metabolismo , Filtro Sensorial/genética , Filtro Sensorial/fisiologia
6.
Rev Sci Instrum ; 85(11): 11D819, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430232

RESUMO

A Nd:YAG Thomson scattering system has been developed for Heliotron J. The system consists of two 550 mJ 50 Hz lasers, large collection optics, and 25 radial channel (∼1 cm spatial resolution) interference polychromators. This measurement system achieves a S/N ratio of ∼50 for low-density plasma (ne ∼ 0.5 × 10(19) m(-3)). A time evolution of electron temperature profiles was measured with this system for a high-intensity gas-puff (HIGP) fueling neutral-beam-injection plasma. The peripheral temperature of the higher-density phase after HIGP recovers to the low-density pre-HIGP level, suggesting that improving particle transport in the HIGP plasma may be possible.

7.
Rev Sci Instrum ; 85(11): 11E814, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430379

RESUMO

A fluctuation analysis technique using analytic signals is proposed. Analytic signals are suitable to characterize a single mode with time-dependent amplitude and frequency, such as an MHD mode observed in fusion plasmas since the technique can evaluate amplitude and frequency at a specific moment without limitations of temporal and frequency resolutions, which is problematic in Fourier-based analyses. Moreover, a concept of instantaneous phase difference is newly introduced, and error of the evaluated phase difference and its error reduction techniques using conditional/ensemble averaging are discussed. These techniques are applied to experimental data of the beam emission spectroscopic measurement in the Heliotron J device, which demonstrates that the technique can describe nonlinear evolution of MHD instabilities. This technique is widely applicable to other diagnostics having necessity to evaluate phase difference.

8.
Rev Sci Instrum ; 85(5): 053506, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24880368

RESUMO

A novel reconstruction method is developed for acquiring the electron density profile from multi-channel interferometric measurements of strongly asymmetrical toroidal plasmas. It is based on a regularization technique, and a generalized cross-validation function is used to optimize the regularization parameter with the aid of singular value decomposition. The feasibility of method could be testified by simulated measurements based on a magnetic configuration of the flexible helical-axis heliotron device, Heliotron J, which has an asymmetrical poloidal cross section. And the successful reconstruction makes possible to construct a multi-channel Far-infrared laser interferometry on this device. The advantages of this method are demonstrated by comparison with a conventional method. The factors which may affect the accuracy of the results are investigated, and an error analysis is carried out. Based on the obtained results, the proposed method is highly promising for accurately reconstructing the electron density in the asymmetrical toroidal plasma.

9.
J Endocrinol ; 221(3): 371-80, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24639470

RESUMO

Ghrelin is a multifunctional peptide that promotes an increase of food intake and stimulates GH secretion. Ghrelin secretion is regulated by nutritional status and nutrients. Although a high-protein (HP) diet increases plasma ghrelin secretion in mammals, the mechanisms and the roles of the elevated ghrelin concentrations due to a HP diet have not been fully established. To clarify the roles of elevated acylated ghrelin upon intake of a HP diet, we investigated the regulation of ghrelin concentrations in plasma and tissues in wethers fed with either the HP diet or the control (CNT) diet for 14 days, and examined the action of the elevated plasma ghrelin by using a ghrelin-receptor antagonist. The HP diet gradually increased the plasma acylated-ghrelin concentrations, but the CNT diet did not. Although the GH concentrations did not vary significantly across the groups, an injection of ghrelin-receptor antagonist enhanced insulin levels in circulation in the HP diet group. In the fundus region of the stomach, the ghrelin levels did not differ between the HP and CNT diet groups, whereas ghrelin O-acyltransferase mRNA levels were higher in the group fed with HP diet than those of the CNT diet group were. These results indicate that the HP diet elevated the plasma ghrelin levels by increasing its synthesis; this elevation strongly suppresses the appearance of insulin in the circulation of wethers, but it is not involved in GH secretion. Overall, our findings indicate a role of endogenous ghrelin action in secretion of insulin, which acts as a regulator after the consumption of a HP diet.


Assuntos
Dieta , Proteínas Alimentares/administração & dosagem , Grelina/sangue , Insulina/sangue , Aciltransferases/genética , Aciltransferases/metabolismo , Animais , Glicemia/metabolismo , Fundo Gástrico/efeitos dos fármacos , Fundo Gástrico/metabolismo , Expressão Gênica/efeitos dos fármacos , Grelina/metabolismo , Cabras , Hormônio do Crescimento/sangue , Imuno-Histoquímica , Insulina/metabolismo , Secreção de Insulina , Masculino , Oligopeptídeos/farmacologia , Orquiectomia , Receptores de Grelina/antagonistas & inibidores , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
J Anim Sci ; 90(13): 4807-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22871937

RESUMO

High-carbohydrate or high-fat diets have been demonstrated to change ghrelin concentrations in plasma; however, there remains a need to clarify the effects of dietary protein on the interaction between circulating GH and ghrelin concentrations in the ruminant. In this study, we investigated the postprandial changes in plasma concentrations of GH and ghrelin and their interactions when wethers were fed either a high-protein (HP; 40% CP) or a low-protein (LP; 10% CP) diet for 2 wk. The wethers were divided into 2 groups and fed once a day for 2 wk in a randomized crossover design. Each diet contained the same level of ME. Blood was collected from the animals at specific times over 24 h to measure hormones and metabolites. Feeding once a day caused a prompt reduction in the GH and ghrelin concentrations regardless of the type of diet that the wethers consumed. The preprandial concentrations (P = 0.04), area under the curve (AUC; P = 0.04), and incremental AUC (iAUC; P = 0.06) for ghrelin in HP-fed wethers were or tended to be greater than those in LP-fed wethers although concentrations for GH were the same for both diets (P = 0.23). In addition, the time it took for the postprandial ghrelin concentrations to recover to the preprandial concentrations was greater in HP-fed wethers than in LP-fed wethers although this was not true for GH concentrations. Similarly, as for ghrelin, postprandial increase (P < 0.001) and AUC (P = 0.03) for insulin concentration was greater in the HP-fed wethers than in the LP-fed wethers. From these findings, we concluded that dietary proteins (or some other derived metabolites) may dissociate the interaction between plasma concentrations of GH and ghrelin in wethers.


Assuntos
Ração Animal/análise , Proteínas Alimentares/administração & dosagem , Grelina/sangue , Hormônio do Crescimento/sangue , Carneiro Doméstico/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estudos Cross-Over , Masculino , Período Pós-Prandial
11.
J Chemother ; 21(1): 80-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19297278

RESUMO

TS-1 is a novel oral anticancer agent comprised of tegafur, a prodrug of 5- flurouracil, and two modulators. A phase i study of tS-1 plus carboplatin combination therapy was conducted to determine the maximum tolerated dose (MTD), recommended dose (RD), and dose limiting toxicities (DLT) in advanced non-small-cell lung cancer (NSClC). TS-1 was given orally at a dose of 80 mg/m(2)/day for 2 weeks, followed by a 2-week rest. Carboplatin was given intravenously on day 8 at a dose of 4.0, 5.0, 6.0 area under the curve (AUC) values. Fifteen patients with advanced NSClC were analyzed. the grade 3-4 toxicities observed during the first cycle were febrile neutropenia (6%), anemia (6%), anorexia (6%), and diarrhea (6%). these toxicities were reversible and manageable. The MTD for carboplatin was evaluated to be more than 6.0 AUC values, as one of six patients developed Dlt at this dose. the RD for carboplatin was estimated as 6.0 AUC values. Objective responses were seen in five patients (response rate 33%).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Área Sob a Curva , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Combinação de Medicamentos , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Ácido Oxônico/administração & dosagem , Ácido Oxônico/efeitos adversos , Tegafur/administração & dosagem , Tegafur/efeitos adversos
12.
Clin Exp Allergy ; 39(1): 138-46, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18778270

RESUMO

BACKGROUND: Although it has been suggested that the use of tachykinin receptor antagonists might prove to be an effective treatment for allergic rhinitis (AR), they are not used clinically. Therefore, we decided to examine the effects of tachykinin receptor antagonists on AR symptoms in an appropriate experimental model. OBJECTIVE: To evaluate newly developed tachykinin receptor antagonists in a Japanese cedar pollen-induced AR model and to determine their effect on allergen-induced sneezing, nasal blockage, and nasal hyperresponsiveness (NHR). METHODS: Sensitized guinea-pigs were challenged by forced inhalation of pollen once every week. Sneezing and nasal blockage were observed after pollen challenges. NHR (nasal blockage) to an intranasal application of leukotriene D(4) was assessed 2 days after an antigen challenge. We also evaluated whether intranasal dosing with a tachykinin causes NHR. NK(1) and NK(2) receptor antagonists were administered before an intranasal treatment with antigen or tachykinin. Amounts of tachykinins present in nasal cavity lavage fluid were measured by an enzyme immunoassay. RESULTS: Although an NK(1) and NK(2) receptor dual antagonist showed no effect on pollen-induced sneezing and biphasic nasal blockage, it did completely suppress the development of NHR. Experiments using specific NK(1) or NK(2) receptor antagonists revealed that NK(2) receptor activation was preferentially involved in the development of hyperresponsiveness. Increases in the levels of substance P (SP) and neurokinin A (NKA) in the nasal tissue were noted 20 min-1 h after the challenge. Intranasal instillation of either SP or NKA-induced NHR, which was almost completely inhibited by NK(2) receptor antagonists and partially inhibited by NK(1) receptor antagonists. CONCLUSIONS: SP and NKA, which are released early after the challenge, mediate the development of NHR by preferentially activating NK(2) receptors. Therefore, NK(2) receptor antagonists might prove to be effective treatment of AR.


Assuntos
Alérgenos/imunologia , Modelos Animais de Doenças , Pólen/imunologia , Rinite Alérgica Sazonal/fisiopatologia , Taquicininas/metabolismo , Animais , Cobaias , Humanos , Líquido da Lavagem Nasal/química , Obstrução Nasal , Testes de Provocação Nasal , Neurocinina A/metabolismo , Nariz , Receptores da Neurocinina-2/antagonistas & inibidores , Receptores da Neurocinina-2/uso terapêutico , Receptores de Taquicininas/antagonistas & inibidores , Receptores de Taquicininas/uso terapêutico , Rinite Alérgica Sazonal/tratamento farmacológico , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/metabolismo , Espirro , Substância P/metabolismo
13.
Oncogene ; 27(57): 7162-70, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-18776920

RESUMO

Ectopic expression of metabotropic glutamate receptor subtype 1 (mGluR1) in mouse melanocytes induces melanoma formation. Although requirement of mGluR1 for development of melanoma in the initial stage has been demonstrated, its role in melanoma growth in vivo remains unclear. In this study, we developed novel transgenic mice that conditionally express mGluR1 in melanocytes, using a tetracycline regulatory system. Pigmented lesions on the ears and tails of the transgenic mice began to appear 29 weeks after activation of the mGluR1 transgene, and the transgenic mice produced melanomas at a frequency of 100% 52 weeks after transgene activation. Subsequent inactivation of the mGluR1 transgene in melanoma-bearing mice inhibited melanoma growth with reduction of immunoreactivity to phosphorylated ERK1/2, whereas mice with persistent expression of mGluR1 developed larger melanoma burdens. mGluR1 expression is thus required not only for melanoma development but also for melanoma growth in vivo. These findings suggest that growth of melanoma can be inhibited in vivo by eliminating only one of the multiple genetic anomalies involved in tumorigenesis.


Assuntos
Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Animais , Western Blotting , Expressão Gênica , Genes ras , Melanoma Experimental/patologia , Camundongos , Camundongos Transgênicos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/patologia
14.
J Anim Sci ; 86(7): 1526-32, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18344300

RESUMO

Urea is an important reutilizable nitrogen source for the ruminant and is mainly synthesized through the urea cycle in the liver. The cycle is undertaken by 5 enzymes: carbamoyl phosphate synthetase (CPS), ornithine transcarbamoylase (OTC), arginino-succinate synthetase (AS), argininosuccinate lyase (AL), and arginase. The purpose of this study was to investigate changes in the activity of the enzymes and mRNA expression, given that previous observations have indicated an increase in plasma urea concentrations with age in Holstein calves. First, plasma concentrations of metabolites and hormones were determined in calves at 1, 3, 8, 13, and 19 wk of age (n = 4, weaned at 6 wk of age). The plasma concentration of urea drastically increased after weaning (P < 0.001). The plasma concentration of glucose was lowest at 8 wk. The plasma concentration of IGF-I gradually increased with age, although those of NEFA, glucagon, and cortisol decreased (P < 0.001). Concentrations of triglyceride, alpha-amino nitrogen, growth hormone, and insulin did not change significantly with age of the calf. Next, using the liver tissues taken from calves at 2, 13, and 19 wk of age (n = 4 to 6 at each time point, weaned at 6 wk of age), we measured the activity and mRNA expression of the enzymes by biochemical methods and quantitative reverse transcription-PCR, respectively. The activities of CPS (P < 0.001), OTC (P = 0.001), and AS (P = 0.015) increased with age, whereas AL (P = 0.003) decreased. Although mRNA expression was decreased with age for AL (P = 0.002) and arginase (P = 0.007), no significant change was observed for CPS, OTC, or AS mRNA expression. We conclude that the increased urea production in the liver may be explained not only by an increase in the activities of the urea cycle enzymes, but also by increased ammonia production by rumen fermentation and gluconeogenesis from amino acids around weaning time.


Assuntos
Bovinos/metabolismo , Fígado/metabolismo , Ureia/metabolismo , Animais , Animais Lactentes , Arginase/biossíntese , Arginase/genética , Argininossuccinato Liase/biossíntese , Argininossuccinato Liase/genética , Argininossuccinato Sintase/biossíntese , Argininossuccinato Sintase/genética , Glicemia/metabolismo , Carbamoil-Fosfato Sintase (Amônia)/biossíntese , Carbamoil-Fosfato Sintase (Amônia)/genética , Bovinos/sangue , Ácidos Graxos não Esterificados/sangue , Glucagon/sangue , Hormônio do Crescimento/sangue , Hidrocortisona/sangue , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/enzimologia , Masculino , Ornitina Carbamoiltransferase/biossíntese , Ornitina Carbamoiltransferase/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Triglicerídeos/sangue , Ureia/sangue
15.
Thorax ; 63(9): 810-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18276722

RESUMO

BACKGROUND: A Th1 predominant immune response has been shown in acute hypersensitivity pneumonitis. Predominance of Th2 appears to favour the development of pulmonary fibrosis through the profibrotic process and has been described as crucial in the progression of idiopathic pulmonary fibrosis. Chronic bird fancier's lung (cBFL) can present with a histological pattern of usual interstitial pneumonia (UIP)-like lesions. Little is known about the Th1/Th2 balance in the pathogenesis of cBFL. METHODS: To evaluate the relevance of Th1-type chemokines (interferon-inducible protein, IP-10) and Th2-type chemokines (thymus- and activation-regulated chemokine, TARC) and their receptors (CXCR3 and CCR4) to the histological patterns of cBFL, 40 patients with cBFL who underwent surgical lung biopsies, 12 with acute BFL (aBFL) and 10 healthy volunteers were analysed. IP-10 and TARC levels in serum and bronchoalveolar lavage (BAL) fluid were measured by ELISA. Immunohistochemistry for CXCR3 and CCR4 was performed on surgical lung specimens. RESULTS: The ratio of TARC to IP-10 in the serum of patients with UIP-like lesions was significantly higher than in patients with cNSIP/OP-like lesions, aBFL and healthy volunteers. The ratio of CCR4 to CXCR3 in patients with UIP-like lesions was significantly higher than in those with cNSIP/OP-like lesions and fNSIP-like lesions. The ratio of CCR4-positive to CXCR3-positive cells correlated with the ratio of TARC to IP-10 in serum. CONCLUSIONS: A Th2 predominant immune response may play an important role in the development of UIP-like lesions, as already observed in idiopathic pulmonary fibrosis. A Th1 predominance may play a role in the development of cNSIP/OP-like lesions in cBFL.


Assuntos
Pulmão do Criador de Aves/metabolismo , Quimiocina CCL17/metabolismo , Quimiocina CXCL10/metabolismo , Fibrose Pulmonar/metabolismo , Pulmão do Criador de Aves/etiologia , Pulmão do Criador de Aves/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/imunologia , Receptores CCR4/metabolismo , Receptores CXCR3/metabolismo
16.
J Clin Pharm Ther ; 32(3): 277-85, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17489880

RESUMO

BACKGROUND: Upregulation of oligopeptide transport activity by dietary protein, certain dipeptides and amino acids has been reported in the rat intestine and a human intestinal cell line. OBJECTIVE: In this study, the pharmacokinetics of cefdinir were investigated after L-phenylalanine supplementation and a high-protein diet (HPD) in humans to explore changes in the activities of intestinal and renal oligopeptide transporters. METHODS: A normal-protein diet (NPD, 73.2 +/- 2.6 g/day), NPD + l-phenylalanine (7.5 g/day), or HPD (141.3 +/- 3.7 g/day) was given to six male healthy volunteers for 12 days followed by a single dose of cefdinir after an overnight fast in a randomized three-way crossover study with a 22-day washout. Blood and urine were collected over a 12-h period after administration of cefdinir. Concentrations of cefdinir in plasma and/or urine were measured by high-performance liquid chromatography. RESULTS: Plasma concentrations and urinary excretion of the drug did not change throughout the study. Physiological variables and laboratory values did not reveal any differences between the three periods except for serum and urinary nitrogen levels and serum triglyceride. DISCUSSION: A reason for the unchanged pharmacokinetics of cefdinir may be due to lower doses of L-phenylalanine and protein in humans than in animals when converting animal effective doses to humans. CONCLUSION: In humans, L-phenylalanine supplementation and HPD do not seem to upregulate intestinal and renal oligopeptide transport in the ranges of duration and dose examined.


Assuntos
Cefalosporinas/farmacocinética , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Fenilalanina/administração & dosagem , Adulto , Alanina Transaminase/sangue , Antibacterianos/sangue , Antibacterianos/farmacocinética , Antibacterianos/urina , Área Sob a Curva , Nitrogênio da Ureia Sanguínea , Cefdinir , Cefalosporinas/sangue , Cefalosporinas/urina , Estudos Cross-Over , Humanos , Absorção Intestinal/efeitos dos fármacos , Testes de Função Renal , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Política Nutricional , Projetos Piloto , Fatores de Tempo , Triglicerídeos/sangue
17.
Biomed Mater Eng ; 16(3): 157-69, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16518015

RESUMO

Three-dimensional finite element analysis was performed for thin hydroxyapatite (HA) coated and titanium dental implants to study the effects on stress/strain distribution in the mandible with application of axial and oblique loads. The implants were of screw and cylinder types. With an axial load, the maximum equivalent bone stresses in the titanium implants were 21.5 and 29.0 MPa for the cylinder and screw types respectively, and the stress and strain distributions differed. For the cylinder type, the highest stress was located at the implant base, and for the screw type, it was located at the top edge of the first thread within the cortical bone. For the HA-coated cylinder and screw implants, the maximum equivalent bone stresses were 7.1 and 7.2 MPa respectively. The stress and strain distributions were similar, and the highest stress was located on the upper side of the cortical bone around the implant neck for both implants. Of the implants examined, the screw type HA-coated implant had the most uniform stress distribution in bone.


Assuntos
Implantes Dentários , Durapatita/química , Mandíbula/fisiopatologia , Mandíbula/cirurgia , Modelos Biológicos , Suporte de Carga/fisiologia , Anisotropia , Força de Mordida , Placas Ósseas , Parafusos Ósseos , Materiais Revestidos Biocompatíveis/química , Força Compressiva/fisiologia , Simulação por Computador , Desenho Assistido por Computador , Elasticidade , Análise de Falha de Equipamento/métodos , Análise de Elementos Finitos , Humanos , Teste de Materiais , Desenho de Prótese , Estresse Mecânico , Titânio/química
18.
J Clin Pharm Ther ; 30(6): 611-22, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16336295

RESUMO

BACKGROUND: MKC-733, a 5-HT(3) receptor partial agonist, is a novel enteroprokinetic compound. OBJECTIVE: The aim of this study was to explore the effects of MKC-733 on bowel motility and symptoms in a small group of subjects with constipation. Tolerability was also examined. METHODS: The study was conducted in a single-blind and dose-escalation manner on 14 male and female subjects with constipation aged 22-67 years. After a 1 week run-in period, subjects were treated with placebo (b.i.d.) for 1 week, and 0.2 and 0.5 mg of MKC-733 (b.i.d.) for 2 weeks sequentially. Geometric mean and per cent elimination of surrogate markers of bowel motility were measured by a radio-opaque marker technique at the end of each treatment period. They were analysed on the whole group and subgroups with low (n = 6) and high (n = 8) bowel motility based upon the geometric mean value after placebo treatment. Subjects kept diaries of their bowel habits and gastrointestinal symptoms. RESULTS: Percent elimination increased after treatment with 0.5 mg MKC-733 compared with placebo treatment in the whole group (70.4 +/- 33.5% vs. 47.1 +/- 36.6%, mean +/- SD, P < 0.05). In the low bowel motility group, both geometric mean and percent elimination increased after treatment with 0.5 mg MKC-733 compared with placebo (7.1 +/- 0.9 vs. 5.9 +/- 0.5, P < 0.05; 60.0 +/- 35.8% vs. 13.3 +/- 19.4%, P < 0.05). Stool frequency increased after the first-week treatment with MKC-733 compared with placebo (P < 0.05). Numbers of sensation of incomplete evacuation and gastrointestinal symptoms decreased to half and less after the treatment with MKC-733. No serious adverse effect was noted. CONCLUSION: Multiple doses of 0.5 mg MKC-733 improve bowel motility, which was clearly demonstrated in the subjects with decreased bowel motility. MKC-733 at the doses studied might be effective in increasing stool frequency and reduce gastrointestinal symptoms related to constipation. MKC-733 was well tolerated. Further studies will be needed to clarify efficacy and safety of MKC-733 on a larger population.


Assuntos
Constipação Intestinal/tratamento farmacológico , Motilidade Gastrointestinal/efeitos dos fármacos , Piridinas/uso terapêutico , Quinuclidinas/uso terapêutico , Agonistas do Receptor de Serotonina/uso terapêutico , Adulto , Idoso , Defecação/efeitos dos fármacos , Fezes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/efeitos adversos , Quinuclidinas/efeitos adversos , Agonistas do Receptor de Serotonina/efeitos adversos
19.
Thorax ; 60(8): 665-71, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16061708

RESUMO

BACKGROUND: Chronic bird fancier's lung (BFL) has often been misdiagnosed as one of the idiopathic interstitial pneumonias (IIPs). METHODS: To define the clinical and pathological characteristics of chronic BFL, 26 patients with chronic BFL from whom a surgical lung biopsy specimen was taken between October 1992 and June 2001 were evaluated. The histopathological characteristics of the surgical lung biopsy specimens were examined and correlations between the histopathology and clinical characteristics were analysed. The quality of chronic inflammatory and fibrotic changes was expressed according to the 2002 ATS/ERS consensus classification of IIPs. RESULTS: Two patients were diagnosed as having bronchiolitis obliterans organising pneumonia (BOOP)-like lesions, five as having cellular non-specific interstitial pneumonia (NSIP)-like lesions, and eight as having fibrotic NSIP-like lesions. The other 11 patients were considered to have usual interstitial pneumonia (UIP)-like lesions because of the temporal heterogeneous appearances of the fibrotic changes. However, fibrosis in these patients had developed in centrilobular as well as perilobular areas, suggestive of hypersensitivity pneumonitis. Nineteen patients (73.1%) had multinucleated giant cells, often with cholesterol clefts, while only five patients (19.2%) had granulomas. Patients with BOOP-like or cellular NSIP-like lesions tended to have recurrent acute episodes, whereas patients with UIP-like lesions had an insidious onset. Patients with BOOP-like or cellular NSIP-like lesions had a more favourable outcome than those with fibrotic NSIP-like and UIP-like lesions. CONCLUSIONS: The qualities of chronic inflammatory and fibrotic lesions vary significantly among patients with chronic BFL but correlate with clinical features and prognosis.


Assuntos
Pulmão do Criador de Aves/patologia , Doenças Pulmonares Intersticiais/patologia , Pulmão/patologia , Idoso , Alérgenos , Biópsia/métodos , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/química , Doença Crônica , Consenso , Pneumonia em Organização Criptogênica/classificação , Pneumonia em Organização Criptogênica/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Doenças Pulmonares Intersticiais/classificação , Masculino , Pessoa de Meia-Idade , Prognóstico
20.
Brain Topogr ; 17(1): 13-25, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15669752

RESUMO

This paper reports a revised Wiener filter to resolve the inverse problem for magnetoencephalograms (MEGs) according to the structural and functional constraints based on magnetic resonance imaging (MRI) and functional magnetic resonance imaging (fMRI). Wiener filter-MEG imaging for half field stimulation with the chromatic stimulus resolved fast, slow and late responses in V1, V4 and the inferotemporal cortex, respectively. The time courses of these responses were roughly comparable with those reported by unit recording studies of the corresponding monkey visual cortical areas. Wiener filter-MEG imaging had comparable spatial resolution and better signal to noise ratio than fMRI. The background noise was robust in fMRI responses, but became virtually eliminated in Wiener filter responses. Wiener filter-MEG imaging with upper and lower quadrant field stimulation demonstrated V1 responses differentially distributed respectively in the lower and upper banks of the calcarine sulcus. These results demonstrate that responses in two cortical areas facing close to each other can be resolved by Wiener filter-MEG. The present method provides a way to image brain activities with millisecond- and millimeter-order spatiotemporal resolution.


Assuntos
Mapeamento Encefálico/métodos , Magnetoencefalografia/métodos , Processamento de Sinais Assistido por Computador , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Adulto , Algoritmos , Animais , Artefatos , Haplorrinos/anatomia & histologia , Haplorrinos/fisiologia , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Tempo de Reação/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologia , Fatores de Tempo , Córtex Visual/anatomia & histologia , Vias Visuais/anatomia & histologia
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