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The number of elderly patients with esophageal cancer has increased in recent years. The use of thoracoscopic esophagectomy has also increased, and its minimal invasiveness is believed to contribute to postoperative outcomes. However, the short- and long-term outcomes in elderly patients remain unclear. This study aimed to elucidate the safety and feasibility of minimally invasive esophagectomy in elderly patients. This retrospective study included 207 patients who underwent radical thoracoscopic esophagectomy for thoracic esophageal squamous cell carcinoma at Kobe University Hospital between 2005 and 2014. Patients were divided into non-elderly (<75 years) and elderly (≥75 years) groups. A propensity score matching analysis was performed for sex and clinical T and N stage, with a total of 29 matched pairs. General preoperative data, surgical procedures, intraoperative data, postoperative complications, in-hospital death, cancer-specific survival, and overall survival were compared between groups. The elderly group was characterized by lower preoperative serum albumin levels and higher American Society of Anesthesiologists grade. Intraoperative data and postoperative complications did not differ between the groups. The in-hospital death rate was 4% in the elderly group, which did not significantly differ from the non-elderly group. Cancer-specific survival was similar between the two groups. Although overall survival tended to be poor in the elderly group, it was not significantly worse than that of the non-elderly group. In conclusion, the short- and long-term outcomes of minimally invasive esophagectomy in elderly versus non-elderly patients were acceptable. Minimally invasive esophagectomy is a safe and feasible modality for elderly patients with appropriate indications.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Anciano , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago/cirugía , Esofagectomía/efectos adversos , Estudios de Factibilidad , Mortalidad Hospitalaria , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.
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Background Patients with systemic sclerosis (SSc) frequently suffer from recalcitrant digital ulceration because of impaired cutaneous blood flow (CBF). A simple and accurate CBF measurement would be helpful to evaluate the disease status and efficacy of treatment in such patients. Objectives To examine the feasibility of a newly developed, micromachined integrated laser blood flowmeter (MILBF) for evaluation of abnormal CBF responses in patients with SSc. Methods CBF of finger pulp was measured in eight patients with SSc and in six healthy controls using MILBF. CBF in the steady state and the responses to the arm-raising test and cold provocation were assessed. The therapeutic efficacy of a single and an intensive prostaglandin E(1) (PGE(1)) infusion treatment was also evaluated in some of the SSc patients. Results The patients with SSc showed significantly lower steady-state CBF than controls. The rate of blood flow with cold provocation and the velocity of blood flow recovery after cold provocation (VR-CP) tended to be lower in patients with SSc. Augmentation of amplitude of the digital pulse wave by arm raising (AA-AR) was observed in controls, but not in patients with SSc. We also found that VR-CP and AA-AR may be good markers for evaluating the efficacy of vasodilatory treatment. It should be noted that the examined patients did not complain of any pain and/or distress during the arm-raising test, as opposed to during cold provocation. Conclusions CBF assessment using MILBF and an arm-raising test is accurate, noninvasive and well tolerated and thus the combination may be a better alternative method to evaluate abnormal CBF and efficacy of treatment in patients with SSc.
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Dedos/irrigación sanguínea , Flujometría por Láser-Doppler/instrumentación , Enfermedad de Raynaud/diagnóstico , Esclerodermia Sistémica/fisiopatología , Anciano , Alprostadil/uso terapéutico , Frío , Diseño de Equipo , Femenino , Humanos , Flujometría por Láser-Doppler/métodos , Masculino , Persona de Mediana Edad , Enfermedad de Raynaud/tratamiento farmacológico , Enfermedad de Raynaud/etiología , Flujo Sanguíneo Regional , Esclerodermia Sistémica/tratamiento farmacológico , Piel/irrigación sanguínea , Resultado del Tratamiento , Vasodilatadores/uso terapéuticoRESUMEN
The biophysical investigation of living cells is currently possible by single molecular detection methods such as fluorescence correlation spectroscopy (FCS). FCS is applied for measuring the dynamic mobility of target molecules in living cells; however, the conventional FCS systems still lack quantitative analysis for many regions of interests (ROI) in real time. To improve this situation, we have developed a novel multipoint FCS system (M-FCS) that can measure multipoint correlation functions in the cell simultaneously. To evaluate its performance, we measured correlation functions for rhodamine 6G (Rh6G) in homogeneous conditions and for green fluorescence protein (GFP) in HeLa cells. We conclude that M-FCS possesses reliable performance. As a pharmacological application, glucocorticoid receptor protein fused GFP (GR-GFP) was transfected in HeLa cells and FCS measurements were carried out in the cytoplasm and the nucleus simultaneously. The translocation of GR-GFP from the cytoplasm to the nucleus by ligand stimulation was observed with laser scanning microscopy (LSM) and M-FCS. Particularly in the nucleus, the slower diffusion of GR-GFP suggested molecular interactions after the translocation. These data imply that M-FCS can be applied for quantitative analysis of kinetic processes in living cells.
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Interpretación de Imagen Asistida por Computador/métodos , Microscopía Fluorescente/métodos , Transporte de Proteínas/fisiología , Receptores de Glucocorticoides/metabolismo , Espectrometría de Fluorescencia/métodos , Difusión , Células HeLa , Humanos , Receptores de Glucocorticoides/ultraestructuraRESUMEN
The effects of dietary sesamin on the hepatic metabolism of arachidonic (AA) and eicosapentaenoic (EPA) acids, were investigated with respect to their beta-oxidation and secretion as triacylglycerol (TG). For 2 wk, rats were fed three types of dietary oils: (i) corn oil (control) group; (ii) EPA group: EPA ethyl esters/rapeseed oil = 2:3; (iii) AA group: AA ethyl esters/palm oil/perilla oil = 2:2:1, with or without 0.5% (w/w) of sesamin. Dietary sesamin significantly increased the activities of hepatic mitochondrial and peroxisomal fatty acid oxidation enzymes (mitochondrial carnitine acyltransferase I, acyl-CoA dehydrogenase, and peroxisomal acyl-CoA oxidase). Dietary EPA increased mitochondrial carnitine acyltransferase I and peroxisomal acyl-CoA oxidase. Dietary AA, however, had an effect on peroxisomal acyl-CoA oxidase only. In whole liver and the TG fraction, EPA and AA concentrations were significantly increased by dietary EPA and AA, respectively, and were decreased by dietary sesamin. In hepatic mitochondria and peroxisomes, EPA concentration was increased by dietary EPA, but AA was not changed by dietary AA. The addition of dietary sesamin to the EPA-supplemented diet significantly decreased the EPA concentration compared to concentrations found with consumption of dietary EPA alone. These results suggest that sesamin increased beta-oxidation enzyme activities and reduced hepatic EPA and AA concentrations by degradation. The stimulating effect of sesamin on beta-oxidation, however, was more significant in the EPA group than in the AA group. Hepatic AA concentration was altered by the joint effect of sesamin through esterification into TG and the stimulation of beta-oxidation.
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Ácido Araquidónico/metabolismo , Dioxoles/farmacología , Ácido Eicosapentaenoico/metabolismo , Lignanos/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Mitocondrias Hepáticas/efectos de los fármacos , Peroxisomas/efectos de los fármacos , Animales , Ácido Araquidónico/farmacología , Peso Corporal/efectos de los fármacos , Cromatografía en Capa Delgada , Dioxoles/administración & dosificación , Ácido Eicosapentaenoico/farmacología , Conducta Alimentaria/efectos de los fármacos , Lignanos/administración & dosificación , Hígado/enzimología , Masculino , Mitocondrias Hepáticas/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Peroxisomas/metabolismo , Ratas , Ratas WistarRESUMEN
In this study, a new marine oil that contains 45% docosahexaenoic acid (DHA, 22:6n-3) and 13% docosapentaenoic acid (DPA, 22:5n-6) was administered to rats. The metabolism and distribution of DPA in rats was investigated. In experiment 1, the effects of DHA and n-6 fatty acids (linoleic acid, LA; arachidonic acid, AA; and DPA) on AA contents were investigated in vivo. LA group: LA 25%, DHA 30%; LA-DPA group: LA 15%, DPA 10%, DHA 35%; LA-AA-DPA group: LA 10%, AA 5%, DPA 10%, DHA 35% were administered to rats for 4 wk. In the liver, the AA content in the LA-DPA and LA-AA-DPA groups was significantly higher than in the LA group. The decreased AA contents in the LA group might be caused by DHA administration. Although DHA also was administered in the LA-DPA and LA-AA-DPA groups, the AA contents in these two groups did not decrease. These results suggested that DPA retroconverted to AA, blunting the decrease in AA content caused by DHA administration. To conduct a detailed investigation on DPA metabolism and its relation with AA and DHA, rat hepatocytes were cultured with purified DPA and DHA for 24 h. We discovered the retroconversion of DPA to AA occurred only when AA content was decreased by a high DHA administration; it did not occur when AA content was maintained at a normal level.
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Ácidos Grasos Insaturados/análisis , Ácidos Grasos Insaturados/metabolismo , Hígado/química , Hígado/metabolismo , Animales , Ácido Araquidónico/metabolismo , Química Encefálica , Células Cultivadas , Grasas Insaturadas en la Dieta/administración & dosificación , Grasas Insaturadas en la Dieta/metabolismo , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/análisis , Ácidos Docosahexaenoicos/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/administración & dosificación , Masculino , Especificidad de Órganos , Ratas , Ratas Wistar , Testículo/química , Testículo/metabolismoRESUMEN
Thiobacillus ferrooxidans strain NASF-1 grown aerobically in an Fe2+ (3%)-medium produces hydrogen sulfide (H2S) from elemental sulfur under anaerobic conditions with argon gas at pH 7.5. Sulfur reductase, which catalyzes the reduction of elemental sulfur (S0) with NAD(P)H as an electron donor to produce hydrogen sulfide (H2S) under anaerobic conditions, was purified 69-fold after 35-65% ammonium sulfate precipitation and Q-Sepharose FF, Phenyl-Toyopearl 650 ML, and Blue Sepharose FF column chromatography, with a specific activity of 57.6 U (mg protein)(-1). The purified enzyme was quite labile under aerobic conditions, but comparatively stable in the presence of sodium hydrosulfite and under anaerobic conditions, especially under hydrogen gas conditions. The purified enzyme showed both sulfur reductase and hydrogenase activities. Both activities had an optimum pH of 9.0. Sulfur reductase has an apparent molecular weight of 120,000 Da, and is composed of three different subunits (M(r) 54,000 Da (alpha), 36,000 Da (beta), and 35,000 Da (gamma)), as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is the first report on the purification of sulfur reductase from a mesophilic and obligate chemolithotrophic iron-oxidizing bacterium.
RESUMEN
As a step toward a field-use spectrometer based on Fourier-transform spectroscopy, we have developed a prism-scanning interferometer. It consists of a sliding triangular prism with two mirror surfaces attached to a fixed triangular-prism beam splitter. This design eliminates the effect of ambient air and simplifies alignment, which can otherwise be time consuming. It also halves the stage-moving distance, because the optical path difference is doubled, since both mirrors move while the sliding prism is scanning. We have tested the basic operation of the prototype and found that the spectral resolution and the wavelength scale agree well with our simple calculation.
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In this study, we examined the distribution and metabolism of refined sesame oil lignans (sesamin and episesamin) in rat. For 8 wk rats were fed the diet including 0.5% (w/w) sesame lignans (sesamin and episesamin) with 5% (w/w) corn oil or eicosapentaenoic acid (EPA)-rich oil. The concentrations of sesamin and episesamin in rat liver after their administration for 8 wk were very low; both of them were less than 0.5 microgram/g liver. These were observed in both oil groups although the fatty acid compositions of dietary oils were completely different. No significant difference existed in lymphatic absorption between sesamin and episesamin. To investigate the distribution of sesamin and episesamin in rats, the concentrations of sesamin and episesamin were determined in tissues and serum within 24 h after administration to rats. Sesamin and episesamin may be, at first, incorporated into the liver and then transported to the other tissues (lung, heart, kidney, and brain). They are lost from the body within 24 h after administration. There was no significant difference in lymphatic absorption between sesamin and episesamin, but the amount of sesamin was significantly lower than that of episesamin in all tissues and serum. These results suggest that sesamin is absorbed in lymph the same as episesamin, but that sesamin is subsequently metabolized faster by the liver.
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Dioxoles/metabolismo , Lignanos/metabolismo , Animales , Encéfalo/metabolismo , Dioxoles/farmacocinética , Riñón/metabolismo , Lignanos/farmacocinética , Hígado/metabolismo , Pulmón/metabolismo , Linfa/metabolismo , Masculino , Miocardio/metabolismo , Ratas , Ratas Wistar , Distribución TisularRESUMEN
A monolithically integrated optical displacement sensor based on triangulation and optical beam deflection is reported. This sensor is simple and consists of only a laser diode, a polyimide waveguide, and a split detector (a pair of photodiodes) upon a GaAs substrate. The resultant prototype device is extremely small (750 microm x 800 microm). Experiments have shown that this sensor can measure the displacement of a mirror with resolution of better than 4 nm. Additionally, we have experimentally demonstrated both axial and lateral displacement measurements when we used a cylindrical micromirror (diameter, 125 microm) as a movable external object.
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We have developed an extremely small integrated microencoder whose sides are less than 1 mm long. It is 1/100 the size of conventional encoders. This microencoder consists of a laser diode, monolithic photodiodes, and fluorinated polyimide waveguides with total internal reflection mirrors. The instrument can measure the relative displacement between a grating scale and the encoder with a resolution of the order of 0.01 microm; it can also determine the direction in which the scale is moving. By using the two beams that were emitted from the two etched mirrors of the laser diode, by monolithic integration of the waveguide and photodiodes, and by fabrication of a step at the edge of the waveguide, we were able to eliminate conventional bulky optical components such as the beam splitter, the quarter-wavelength plate, bulky mirrors, and bulky photodetectors.
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In this study, we examined the effect of dietary arachidonic acid (AA) and sesame lignans on the content and n-6/n-3 ratio of polyunsaturated fatty acid (PUFA) in rat liver and the concentrations of triglyceride (TG) and ketone bodies in serum. For 4 wk, rats were fed two types of dietary oils: (i) the control oil diet groups (CO and COS): soybean oil/perilla oil = 5:1, and (ii) the AA-rich oil group (AO and AOS): AA ethyl esters/palm oil/perilla oil = 2:2:1, with (COS and AOS) or without (CO and AO) 0.5% (w/w) of sesame lignans. Dietary AA and sesame lignans significantly affected hepatic PUFA metabolism. AA content and n-6/n-3 ratio in the liver were significantly increased in the AO group, despite the dietary total of n-6 PUFA being the same in all groups, while AOS diet reduced AA content and n-6/n-3 ratio to a level similar to the CO and COS groups. These results suggest that (i) dietary AA considerably affects the hepatic profile and n-6/n-3 ratio of PUFA, and (ii) dietary sesame lignans reduce AA content and n-6/n-3 ratio in the liver. In the AO group, the concentration of acetoacetate was significantly increased, but the ratio of beta-hydroxybutyrate/acetoacetate was decreased. On the other hand, the AO diet increased the concentration of TG in serum by almost twofold as compared to other groups. However, the AOS diet significantly reduced serum TG level as compared to the AO group. In addition, the AOS diet significantly increased the acetoacetate level, but reduced the beta-hydroxybutyrate/acetoacetate ratio. These results suggest that dietary sesame lignans promote ketogenesis and reduce PUFA esterification into TG. This study resulted in two findings: (i) sesame lignans inhibited extreme changes of the n-6/n-3 ratio by reducing hepatic PUFA content, and (ii) the reduction of hepatic PUFA content may have occurred because of the effects of sesame lignans on PUFA degradation (oxidation) and esterification.
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Ácido Araquidónico/administración & dosificación , Grasas Insaturadas en la Dieta/administración & dosificación , Dioxoles/administración & dosificación , Ácidos Grasos Esenciales/química , Ácidos Grasos Esenciales/metabolismo , Lignanos , Animales , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/metabolismo , Cuerpos Cetónicos/sangre , Hígado/metabolismo , Masculino , Ratas , Ratas Wistar , Aceite de Sésamo/administración & dosificación , Triglicéridos/sangreRESUMEN
Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 NeuAcalpha-LacCer, II3 NeuAcalpha2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3 + Gb4 = 58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Le(a) (pentaglycosylceramide) and Le(b) (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.
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Adenocarcinoma Escirroso/metabolismo , Fibroblastos/metabolismo , Globósidos/metabolismo , Neoplasias Gástricas/metabolismo , Trihexosilceramidas/metabolismo , Adenocarcinoma Escirroso/patología , Glicoesfingolípidos/metabolismo , Humanos , Inmunohistoquímica , Neoplasias Gástricas/patología , Células Tumorales CultivadasRESUMEN
From October to December in 1995, an epidemic of infantile gastroenteritis occurred all over Japan except in Hokkaido and Okinawa prefectures. The number of infected infants and young children was estimated to be over 5 million cases [Editorial, IASR 1996]. The stool specimens from patients were examined for the presence of small round structured viruses (SRSVs) by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing of parts of the RNA-dependent RNA polymerase region. Thirty-five of 87 stool specimens examined gave positive results. Genomic variation was investigated by sequence analysis of a 327 bp cDNA region. The nucleotide and deduced amino acid sequences of the ten strains segregated into two distinct groups; one showed 96.0-100% nucleotide and 99.1-100% amino acid identity, the others showed 91.4-99.7% nucleotide and 93.5-100% identity. The main mechanism of transmission remains unknown. However, these data suggest the possibility of person-to-person spread by two or more kinds of SRSV.
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Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Brotes de Enfermedades , Gastroenteritis/epidemiología , Gastroenteritis/virología , Virus Norwalk/genética , Virus Norwalk/aislamiento & purificación , Secuencia de Bases , Niño , Preescolar , Clonación Molecular , ADN Complementario/genética , ADN Viral/genética , Heces/virología , Humanos , Lactante , Japón/epidemiología , Datos de Secuencia Molecular , Virus Norwalk/clasificación , Reacción en Cadena de la Polimerasa , ARN Viral/genética , ARN Viral/aislamiento & purificación , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido NucleicoRESUMEN
Changes in the hepatic concentration of n-3 fatty acids, e.g., eicosapentaenoic acid and linolenic acid, were significantly reduced by their simultaneous administration with sesamin, whereas there was no such effect of sesamin for n-6 and n-9 fatty acids. However, there was no significant difference in lymphatic absorption between eicosapentaenoic acid (n-3) and arachidonic acid (n-6), irrespective of the presence of absence of sesamin.
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Anticolesterolemiantes/farmacología , Dioxoles/farmacología , Ácido Eicosapentaenoico/metabolismo , Lignanos , Hígado/metabolismo , Sistema Linfático/metabolismo , Animales , Ácido Eicosapentaenoico/química , Ácidos Grasos/análisis , Hígado/efectos de los fármacos , Sistema Linfático/efectos de los fármacos , Masculino , Ratas , Ratas WistarRESUMEN
The multidrug resistance modifying activity of a dithiane analogue of tiapamil, Ro 44-5912, was examined in vivo. Results of acute toxicity studies in mice indicated that lethal toxicity occurred with doses greater than 1 mmol/kg of body weight. In a preliminary pharmacokinetic investigation, Ro 44-5912 appeared to have a longer half-life in mice than did its (R) enantiomer Ro 44-5911 (3.15 +/- 0.02 h versus 2.15 +/- 0.14 h) as measured by total radiolabel in plasma. In non-tumour bearing mice, Ro 44-5912 enhanced the toxicity of vinblastine in a manner that was dependent on the dose of both drugs. Vinblastine did not have a significant effect on tumour growth when given to nude mice bearing the parental cell line KB-3-1 at a dose of 1.5 mg/kg once per week for 3 weeks. Combination treatment with Ro 44-5912 markedly enhanced the antitumour activity of vinblastine. Similar results were seen when KB-3-1 tumours were treated with the combination of vinblastine plus cyclosporin A. Another tiapamil analogue, Ro 11-2933, had no enhancing activity with this tumour when used at an equitoxic combination dose. Ro 44-5912 also significantly enhanced vinblastine activity with P-glycoprotein-expressing KB-8-5 tumours. In three independent experiments, Ro 44-5912 enhanced the growth inhibiting activity of vinblastine by a mean of approximately 40%. Neither Ro-11-2933 nor cyclosporin A, at the maximal tolerated doses in combination with vinblastine, led to significant inhibition of KB-8-5 tumour growth compared to treatment with the two vehicles alone. These results show that Ro 44-5912 is an active modulator of drug resistance in vivo.
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Antineoplásicos/uso terapéutico , Bloqueadores de los Canales de Calcio/farmacología , Resistencia a Múltiples Medicamentos , Vinblastina/uso terapéutico , Animales , Antineoplásicos/efectos adversos , Bloqueadores de los Canales de Calcio/administración & dosificación , Ciclosporinas/administración & dosificación , Resistencia a Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células KB/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Propilaminas/administración & dosificación , Trasplante Heterólogo , Vasodilatadores/farmacología , Vinblastina/efectos adversosRESUMEN
Sesamin is a specific inhibitor of delta 5 desaturation, the conversion from dihomo-gamma-linolenic acid (20:3, n-6) to arachidonic acid (AA, 20:4, n-6). Previously, we reported that sesamin inhibited delta 5 desaturation of n-6 fatty acids in rat hepatocytes but not that of n-3 fatty acids, from 20:4 (n-3) to eicosapentaenoic acid (EPA, 20:5, n-3). In this study, we investigated the interaction of sesamin and EPA on delta 5 desaturation of both series and the n-6/n-3 fatty acids ratio by measuring actural fatty acid contents in vivo. Rats were fed three types of dietary oils; 1) linoleic acid (LA, 18:2, n-6): linolenic acid (LLA, 18:3, n-3) = 3:1, n-6/n-3 ratio of 3:1 (LA group), 2) LA:LLA = 1:3, n-6/n-3 ratio of 1:3 (LLA group), 3) LA:LLA:EPA = 1:0.5:3, n-6/n-3 ratio of 1:3.5 (EPA group) with or without sesamin (0.5% w/w) for 4 weeks. In all groups, sesamin administration increased the content of dihomo-gamma-linolenic acid (20:3, n-6) in the liver and decreased the delta 5 desaturation index of n-6 fatty acid, the ratio of 20:4/20:3 (n-6). On the contrary, the delta 5 desaturation index of n-3 fatty acid, the ratio of 20:5 + 22:5 + 22:6/20:4 (n-3), was increased by the administration of sesamin. These results suggest that sesamin inhibits the delta 5 desaturation of n-6 fatty acid, but not that of n-3 fatty acid in rat livers. Sesamin administration decreased incorporation of EPA (n-3) and simultaneously increased the AA (n-6) content in the liver. The n-6/n-3 ratio in the liver was increased by administering sesamin under n-3 rich conditions, i.e., the LLA and EPA groups.
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Anticolesterolemiantes/farmacología , Dioxoles/farmacología , Ácido Eicosapentaenoico/farmacología , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Insaturados/metabolismo , Lignanos , Animales , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Interacciones Farmacológicas , Ácidos Grasos Omega-6 , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Tamaño de los Órganos/efectos de los fármacos , Fosfatidilcolinas/farmacología , Ratas , Ratas Wistar , Distribución TisularRESUMEN
Chitin synthase 2 of Saccharomyces cerevisiae was characterized by means of site-directed mutagenesis and subsequent expression of the mutant enzymes in yeast cells. Chitin synthase 2 shares a region whose sequence is highly conserved in all chitin synthases. Substitutions of conserved amino acids in this region with alanine (alanine scanning) identified two domains in which any conserved amino acid could not be replaced by alanine to retain enzyme activity. These two domains contained unique sequences, Glu561-Asp562-Arg563 and Gln601-Arg602-Arg603-Arg604-Trp605, that were conserved in all types of chitin synthases. Glu561 or arginine at 563, 602, and 603 could be substituted by glutamic acid and lysine, respectively, without significant loss of enzyme activity. However, even conservative substitutions of Asp562 with glutamic acid, Gln601 with asparagine, Arg604 with lysine, or Trp605 with tyrosine drastically decreased the activity, but did not affect apparent Km values for the substrate significantly. In addition to these amino acids, Asp441 was also found in all chitin synthase. The mutant harboring a glutamic acid substitution for Asp441 severely lost activity, but it showed a similar apparent Km value for the substrate. Amounts of the mutant enzymes in total membranes were more or less the same as found in the wild type. Furthermore, Asp441, Asp562, Gln601, Arg604, and Trp605 are completely conserved in other proteins possessing N-acetylglucosaminyltransferase activity such as NodC proteins of Rhizobium bacterias. These results suggest that Asp441, Asp562, Gln601, Arg604, and Trp605 are located in the active pocket and that they function as the catalytic residues of the enzyme.
Asunto(s)
Quitina Sintasa/química , Saccharomyces cerevisiae/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Secuencia Conservada , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Relación Estructura-ActividadRESUMEN
Sesamin is known as a specific inhibitor of delta 5-desaturation, the conversion from dihomo-gamma-linolenic acid (20:3(n=6)) to arachidonic acid (20:4(n-6)). In the previous paper, we reported that sesamin inhibited delta 5-desaturation of n-6 fatty acids in rat hepatocytes but not that of n-3 fatty acids, from 20:4(n-3) to 20:5(n-3). Then, we studied the effects of sesamin on delta 5-desaturation of n-6 and n-3 fatty acids in vivo. Rats were fed two types of diets containing sesamin (0.5% w/w) for 4 weeks as follows: in experiment 1 (Exp. 1) gamma-linolenic acid-rich diet and in experiment 2 (Exp. 2) alpha-linolenic acid-rich diet. The fatty acid composition of liver lipids was compared to those of control groups without sesamin. In both Exps. 1 and 2, sesamin increased the liver weight and phospholipid contents in liver. In Exp. 2, sesamin increased n-6 fatty acids and decreased n-3 fatty acids even though the diet was rich in n-3 fatty acids. Sesamin enhanced the composition ratio of 20:3(n-6) in both Exps. 1 and 2. Decrease of delta 5-desaturation index of n-6 fatty acid, the ratio of 20:4(n-6)/20:3(n-6), by the administration of sesamin suggested that sesamin inhibited the delta 5-desaturation of n-6 fatty acids in the liver. On the contrary, the delta 5-desaturation index of n-3 fatty acids, the ratio of 20:5(n-3) to 18:3(n-3), was increased by sesamin administration in the liver of rats fed alpha-linolenic acid-rich diet (Exp. 2).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Dioxoles/farmacología , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Insaturados/farmacología , Ácidos Grasos/análisis , Lignanos , Hígado/química , Animales , Dieta , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6 , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/metabolismo , Hígado/citología , Hígado/metabolismo , Masculino , Ratas , Ratas Wistar , Aceite de Sésamo , Ácido alfa-Linolénico/metabolismo , Ácido alfa-Linolénico/farmacologíaRESUMEN
Twelve Japanese rice cultivars were converted to CMS by asymmetric protoplast fusion with MTC-5A, the cytoplasm of which was derived from an indica rice, Chinsurah Boro II. With the exception of the cybrids that had a nucleus from Hoshiyutaka, most of these cybrid plants were sterile. The unique sequence downstream from the mitochondrial atp6 of MTC-5A was specifically amplified in the sterile cybrid plants by PCR. All progenies of the cybrid plants carrying this unique sequence were sterile. On the other hand, in some of the sterile cybrid plants in which the unique sequence was not amplified by PCR, fertility was recovered in their progenies. Somaclonal mutation may have caused sterility in these cybrids. Only the cybrid plants that had the unique sequence detected by PCR were CMS. Thus, the CMS plants can be selected rapidly and easily by PCR, at an early stage of plant regeneration. Soon after transplanting the regenerated plants to a green house, fertile cybrids and sterile cybrids produced by somaclonal mutation can be removed. These findings also show that the unique region downstream from atp6 is tightly linked with the CMS phenotype.