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1.
Nature ; 550(7676): 371-374, 2017 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-29052625

RESUMEN

Precise comparisons of the fundamental properties of matter-antimatter conjugates provide sensitive tests of charge-parity-time (CPT) invariance, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons, leptons and baryons have compared different properties of matter-antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron. Here we report a high-precision measurement of in units of the nuclear magneton µN with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic multi-Penning trap system. Our result = -2.7928473441(42)µN (where the number in parentheses represents the 68% confidence interval on the last digits of the value) improves the precision of the previous best measurement by a factor of approximately 350. The measured value is consistent with the proton magnetic moment, µp = 2.792847350(9)µN, and is in agreement with CPT invariance. Consequently, this measurement constrains the magnitude of certain CPT-violating effects to below 1.8 × 10-24 gigaelectronvolts, and a possible splitting of the proton-antiproton magnetic moments by CPT-odd dimension-five interactions to below 6 × 10-12 Bohr magnetons.

2.
Nature ; 524(7564): 196-9, 2015 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-26268189

RESUMEN

Invariance under the charge, parity, time-reversal (CPT) transformation is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent. A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H(-)) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton (q/m)p- to that for the proton (q/m)p and obtain (q/m)p-/(q/m)p − 1 =1(69) × 10(-12). The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons as well as the respective figure of merit of the standard model extension by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of <720 parts per trillion. By following the arguments of ref. 11, our result can be interpreted as a stringent test of the weak equivalence principle of general relativity using baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of |α − 1| < 8.7 × 10(-7).

3.
Philos Trans A Math Phys Eng Sci ; 376(2116)2018 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-29459414

RESUMEN

The BASE collaboration investigates the fundamental properties of protons and antiprotons, such as charge-to-mass ratios and magnetic moments, using advanced cryogenic Penning trap systems. In recent years, we performed the most precise measurement of the magnetic moments of both the proton and the antiproton, and conducted the most precise comparison of the proton-to-antiproton charge-to-mass ratio. In addition, we have set the most stringent constraint on directly measured antiproton lifetime, based on a unique reservoir trap technique. Our matter/antimatter comparison experiments provide stringent tests of the fundamental charge-parity-time invariance, which is one of the fundamental symmetries of the standard model of particle physics. This article reviews the recent achievements of BASE and gives an outlook to our physics programme in the ELENA era.This article is part of the Theo Murphy meeting issue 'Antiproton physics in the ELENA era'.

4.
Rev Sci Instrum ; 94(2): 023306, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859041

RESUMEN

We have developed a novel ion source and beam diagnostic system for the production and detection of radioactive francium (Fr) isotopes. The Fr ions are produced using a fusion-evaporation reaction at the RIKEN Nishina Center, Japan. The installation of an infrared heater has enabled a precise and rapid control of the target temperature, and the newly developed diagnostic system allows for a quantitative characterization of the extracted ion beam. With the new system, an analysis of the Fr208-211 isotopes has been performed. Additionally, the flux of Fr210 ions has been estimated as 6.7 × 106 s-1 corresponding to an extraction efficiency of 24.5% and a beam purity of 1.6 × 10-5.

5.
Kyobu Geka ; 65(5): 393-6, 2012 May.
Artículo en Japonés | MEDLINE | ID: mdl-22569498

RESUMEN

There are few case reports of cardiovascular surgery with multiple myeloma. We report 3 cases of cardiovascular surgery with multiple myeloma. CASE 1: A 73-year-old male hemodialytic patient with multiple myeloma was performed off-pump coronary artery bypass grafting (OPCAB) for angina. He was dead on the 72th postoperative day because of sepsis. CASE 2: A 68-year-old female patient with multiple myeloma was performed mitral valve replacement for mitral regurgitation. The postoperative course was uneventful. CASE 3: A 78-year-old male patient, the aorta was replaced with a artificial graft for impending rupture of thoracoabdominal aortic aneurysm. He was diagnosed with multiple myeloma after surgery. He was dead on the 99th postoperative day because of sepsis. One of the affecting prognosis factors is infection and it is intractable.


Asunto(s)
Procedimientos Quirúrgicos Cardiovasculares , Mieloma Múltiple/complicaciones , Anciano , Angina de Pecho/cirugía , Aorta/cirugía , Rotura de la Aorta/cirugía , Puente de Arteria Coronaria Off-Pump , Femenino , Humanos , Masculino , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Resultado del Tratamiento
6.
Int J Biol Macromol ; 44(1): 1-5, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18940197

RESUMEN

Beta-chitin is a biopolymer principally found in shells of squid pen. It has the properties of biodegradability, biocompatibility, chemical inertness, wound healing, antibacterial and anti-inflammatory activities. Hydroxyapatite (HAp) is a natural inorganic component of bone and teeth and has osteoconductive property. In this work, beta-chitin-HAp composite membranes were prepared by alternate soaking of beta-chitin membranes in CaCl2 (pH 7.4) and Na2HPO4 solutions for 2 h in each solution. After 1, 3 and 5 cycles of immersion, beta-chitin membranes were characterized using the SEM, FT-IR, EDS and XRD analyses. The results showed the presence of apatite layer on surface of beta-chitin membranes, and the amounts of size and deposition of apatite layers were increased with increasing number of immersion cycles. Human mesenchymal stem cells (hMSCs) were used for evaluation of the biocompatibility of pristine as well as composite membranes for tissue engineering applications. The presence of apatite layers on the surface of beta-chitin membranes increased the cell attachment and spreading suggesting that beta-chitin-HAp composite membranes can be used for tissue engineering applications.


Asunto(s)
Quitina/química , Durapatita/química , Membranas Artificiales , Ingeniería de Tejidos/métodos , Adhesión Celular/fisiología , Ensayo de Materiales , Células Madre Mesenquimatosas/metabolismo , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
Kyobu Geka ; 62(13): 1178-81, 2009 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-19999099

RESUMEN

An 81-year-old woman was referred to our hospital for surgical treatment for mitral valve regurgitation, tricuspid valve regurgitation and atrial fibrillatory bradycardia. The platelet count on admission was 4.9 x 10(4)/microl. and the results of other studies were compatible with idiopathic thrombocytopenic purpura. Although we performed high-dose transvenous immunoglobulin infusion (400 mg/kg/day) for 5 consecutive days, the platelet count showed no remarkable change. Because of progression of heart failure, we underwent cardiac operation under thrombocytopenic condition. Intra and post-operative platelet transfusion might contribute to postoperative course uneventful without bleeding tendency. In this case, high-dose immunoglobulin therapy was not effective. However the operative course was satisfactory with adequate surgical hemostasis and platelet transfusion.


Asunto(s)
Prótesis Valvulares Cardíacas , Marcapaso Artificial , Implantación de Prótesis , Púrpura Trombocitopénica Idiopática/complicaciones , Anciano de 80 o más Años , Fibrilación Atrial/cirugía , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Insuficiencia de la Válvula Mitral/cirugía , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Insuficiencia de la Válvula Tricúspide/cirugía
8.
Int J Biol Macromol ; 42(4): 335-9, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18279950

RESUMEN

Chitosan a natural based polymer is non-toxic, biocompatible and biodegradable. Chemical modification of chitosan to generate new bifunctional materials and finally would bring new properties depending on the nature of the group introduced. In our present study, we prepared phosphorylated chitosan (P-chitosan) by using H(3)PO(4)/P(2)O(5)/Et(3)PO(4)/hexanol method. From our present method, we got high yield and high degree of substitution (DS). The prepared P-chitosan (DS-1.18) was characterized by FT IR, (13)C NMR, (31)P NMR, elemental, XRD, TGA, DTA and SEM studies. After the phosphorylation, the solubility of the polymer was improved. The P-chitosan showed less thermal stability and crystallinity than the chitosan. It was due to the phosphorylation.


Asunto(s)
Quitosano/química , Quitosano/síntesis química , Materiales Biocompatibles/química , Hexanoles/química , Calor , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Conformación Molecular , Fosforilación , Polímeros/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Temperatura , Difracción de Rayos X
9.
Int J Biol Macromol ; 42(5): 463-7, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-18439672

RESUMEN

Chitin is a biopolymer and it is non-toxic, biodegradable and biocompatible. Chitin has many potential industrial applications because of its abundance, biodegradability, non-toxicity, chemical inertness. beta-Chitin scaffolds were prepared by using saturated calcium chloride alcoholic solution (CaCl(2).6H(2)O/EtOH) and then followed by dialysis with lyophilization. The prepared beta-chitin scaffolds were characterized by FT-IR, scanning electron microscopy (SEM) and thermogravimetric (TGA). The preliminary bioactivity studies of beta-chitin scaffolds were studied by using simulated body fluid (SBF) solution for 7, 14 and 21 days. We also immersed the beta-chitin scaffolds in saturated aqueous CaCl(2) and Na(2)HPO(4) solution over 12h. After 7, 14 and 21 days, the scaffolds were characterized by SEM and FT-IR studies. The SEM studies showed that there is a calcium phosphate layer in the surface as well as in the cross-section of beta-chitin scaffolds. It seems that the beta-chitin scaffolds are useful in the tissue-engineering field.


Asunto(s)
Quitina/síntesis química , Quitina/química , Quitina/ultraestructura , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Temperatura , Ingeniería de Tejidos
10.
Int J Biol Macromol ; 42(4): 309-13, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18036656

RESUMEN

The crystalline structure of beta-chitin from squid pen was investigated by X-ray diffraction (XRD). The purified beta-chitin was prepared from bigfin reefsquid pen. beta-Chitin was treated with saturated calcium chloride dihydrate/alchohol (CaCl(2).2H(2)O/MeOH) solvent system at different conditions for XRD studies. The change of crystallinity of beta-chitin from squid pen was studied by using the fiber photographs on imaging plates. The results showed that the diffraction peak (010) was shifted. It means that the lattice plane (010) interplanarilly spreaded to 3.4A, when the squid pen was washed with water after treatment of Ca solvent. Furthermore, when the squid pen was dried after treatment of Ca solvent and washing with water, interplanar spacing of (010) inversely shrank to 1.1A. These results suggested that Ca solvent especially influences the plane (010) of beta-chitin structure.


Asunto(s)
Calcio/química , Quitina/química , Solventes/química , Alcoholes/química , Animales , Cloruro de Calcio/química , Cristalización , Decapodiformes , Diseño de Equipo , Modelos Químicos , Conformación Molecular , Difracción de Rayos X
11.
Nat Commun ; 8: 14084, 2017 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-28098156

RESUMEN

Our current understanding of the Universe comes, among others, from particle physics and cosmology. In particle physics an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, a striking matter/antimatter imbalance is observed. This contradiction inspires comparisons of the fundamental properties of particles and antiparticles with high precision. Here we report on a measurement of the g-factor of the antiproton with a fractional precision of 0.8 parts per million at 95% confidence level. Our value /2=2.7928465(23) outperforms the previous best measurement by a factor of 6. The result is consistent with our proton g-factor measurement gp/2=2.792847350(9), and therefore agrees with the fundamental charge, parity, time (CPT) invariance of the Standard Model of particle physics. Additionally, our result improves coefficients of the standard model extension which discusses the sensitivity of experiments with respect to CPT violation by up to a factor of 20.

12.
Rev Sci Instrum ; 87(11): 113305, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910537

RESUMEN

We developed highly sensitive image-current detection systems based on superconducting toroidal coils and ultra-low noise amplifiers for non-destructive measurements of the axial frequencies (550-800 kHz) of single antiprotons stored in a cryogenic multi-Penning-trap system. The unloaded superconducting tuned circuits show quality factors of up to 500 000, which corresponds to a factor of 10 improvement compared to our previously used solenoidal designs. Connected to ultra-low noise amplifiers and the trap system, signal-to-noise-ratios of 30 dB at quality factors of >20 000 are achieved. In addition, we have developed a superconducting switch which allows continuous tuning of the detector's quality factor and to sensitively tune the particle-detector interaction. This allowed us to improve frequency resolution at constant averaging time, which is crucial for single antiproton spin-transition spectroscopy experiments, as well as improved measurements of the proton-to-antiproton charge-to-mass ratio.

13.
Kyobu Geka ; 58(9): 827-30, 2005 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-16104571

RESUMEN

We present a case of surgical treatment for a coronary lesion due to aortitis syndrome. A 41-year-old woman, suffering from aortitis syndrome and under prednisolone (PSL) therapy, underwent coronary artery bypass grafting (CABG). Surgical treatment was performed according to the aortic no-touch technique, but the patient showed a poor cardiac performance 5 days after the operation. This accident was resolved by increasing the PSL dose. Aortitis syndrome treated with PSL needs careful perioperative management besides an operative procedure.


Asunto(s)
Síndromes del Arco Aórtico/cirugía , Puente de Arteria Coronaria , Adulto , Antiinflamatorios/administración & dosificación , Síndromes del Arco Aórtico/tratamiento farmacológico , Puente de Arteria Coronaria/métodos , Femenino , Humanos , Prednisolona/administración & dosificación
14.
Kyobu Geka ; 58(10): 911-4, 2005 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-16167820

RESUMEN

It is difficult to save patients with acute left ventricular rupture and cardiac tamponade caused by blunt trauma. A 67-year-old man hospitalized due to sustained multiple blunt trauma. The systolic blood pressure was 40 mmHg. Chest computed tomography (CT) and ultrasonic echocardiography revealed cardiac tamponade. Abdominal CT indicated left renal contusion. Pericardial drainage via the subxiphoid approach drew about 1,000 ml of blood from the pericardial sac, which only transiently increased blood pressure. Median sternotomy and subsequent pericardiotomy revealed pulsatile bleeding jet through a laceration of about 2.0 cm long in the left ventricle near the first diagonal branch. After complete digital compression, the portion was covered by a biological tissue adhesive/sealant sheet (TachoComb), which completely suppressed bleeding. The postoperative course was uneventful. He was discharged from the hospital on the 20th day after the operation.


Asunto(s)
Taponamiento Cardíaco/etiología , Lesiones Cardíacas/etiología , Heridas no Penetrantes/complicaciones , Enfermedad Aguda , Anciano , Taponamiento Cardíaco/cirugía , Lesiones Cardíacas/cirugía , Ventrículos Cardíacos/lesiones , Ventrículos Cardíacos/cirugía , Humanos , Masculino
15.
Peptides ; 10(6): 1247-51, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2622803

RESUMEN

Acute and long-lasting effects of peripheral injection of caerulein (CLN) and cholecystokinin octapeptide (CCK-8) on the gamma-aminobutylic acid (GABA) content and the GABA accumulation by aminooxyacetic acid (AOAA) in the discrete brain regions of mice were examined. The content and accumulation of GABA in the striatum, hypothalamus, and frontal cortex was measured with high performance liquid chromatography with electrochemical detection (HPLC-ECD). The GABA content slightly decreased in the striatum 60 min after CLN and CCK-8 were administered, whereas it slightly increased in the hypothalamus and frontal cortex. Moreover, with CLN and CCK-8, the GABA accumulation after AOAA treatment decreased in the striatum and hypothalamus 30 min after injection. Meanwhile, when administering CLN, the GABA content as well as the GABA accumulation after AOAA treatment increased in the striatum and frontal cortex 1 day after injection, and continued to increase the second and third day in the striatum. These results showed that peripheral injection of CLN and CCK-8 had effects on the central GABAergic system with local specific actions, and also the long-lasting and time-dependent biphasic effects of CLN.


Asunto(s)
Encéfalo/efectos de los fármacos , Ceruletida/farmacología , Sincalida/farmacología , Ácido gamma-Aminobutírico/metabolismo , Ácido Aminooxiacético/farmacología , Animales , Encéfalo/metabolismo , Ceruletida/administración & dosificación , Cuerpo Estriado/metabolismo , Lóbulo Frontal/metabolismo , Hipotálamo/metabolismo , Inyecciones Intraperitoneales , Masculino , Ratones , Ratones Endogámicos , Sincalida/administración & dosificación , Factores de Tiempo
16.
Ann Thorac Surg ; 70(6): 2161-3, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11156148

RESUMEN

A 58-year old woman with idiopathic thrombocytopenic purpura underwent mitral and aortic valve replacements and tricuspid annuloplasty. Preoperative therapeutic interventions including prednisone and immunoglobulin were successful in elevating the platelet count to 93,000/ mm2. Furthermore, we used nafamostat mesilate for coagulopathy prophylaxis during cardiopulmonary bypass. Postoperative bleeding was average and clinical course was uneventful. The perioperative management for patients with idiopathic thrombocytopenic purpura requiring cardiac operation is reviewed.


Asunto(s)
Anticoagulantes/uso terapéutico , Guanidinas/uso terapéutico , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas , Complicaciones Intraoperatorias/tratamiento farmacológico , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Válvula Aórtica/cirugía , Benzamidinas , Puente Cardiopulmonar , Femenino , Enfermedades de las Válvulas Cardíacas/sangre , Humanos , Persona de Mediana Edad , Válvula Mitral/cirugía , Recuento de Plaquetas , Válvula Tricúspide/cirugía
17.
Toxicol Lett ; 54(2-3): 345-53, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2260129

RESUMEN

The arsenic trioxide (AsT) content, and monoamine levels in the cerebral cortex, hippocampus, hypothalamus and corpus striatum were determined in mice administered AsT (3 and 10 mg/kg) for 14 days. The vertical and horizontal motor activity was also examined. The AsT content in discrete brain areas differed but was clearly dose-dependent. Metabolites of norepinephrine and dopamine increased in the cerebral cortex, hippocampus and hypothalamus and decreased in the corpus striatum in AsT-treated mice. Metabolites of 5-hydroxytryptamine increased in all the discrete brain areas. The vertical and horizontal motor activity was increased by AsT at 3 mg/kg and decreased by AsT at 10 mg/kg. These results show that AsT modifies CNS metabolism and function at low doses. AsT penetrates the blood-brain barrier to cause these effects.


Asunto(s)
Arsénico/toxicidad , Arsenicales , Química Encefálica , Encéfalo/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Óxidos , Administración Oral , Animales , Arsénico/análisis , Trióxido de Arsénico , Encéfalo/metabolismo , Masculino , Ratones
18.
Anat Embryol (Berl) ; 203(2): 77-87, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11218061

RESUMEN

The cyclin-dependent kinase (CDK) inhibitors p27Kip1 and p57Kip2 are thought to regulate progression of the cell cycle. We have previously shown that the phenotypes of p27-/- mice are substantially different from those of p57-/- mice, suggesting that spatial and temporal expression patterns of p27Kip1 and p57Kip2 might be distinct. In this study, the roles of p27Kip1 and p57Kip2 in development were examined by characterizing their expression patterns during mouse embryogenesis by immunohistochemical analysis. Whereas certain organs and tissues (brain, lens, ganglion, lung, heart, liver, skin and kidney) expressed both proteins, others expressed only p27Kip1 (thymus, spleen, retina, testis and ovary) or only p57Kip2 (gut, palate, pancreas, cartilage and skeletal muscle). In addition, some organs expressed both p27Kip1 and p57Kip2 but showed mutually exclusive patterns of distribution among tissues. Thus, in the adrenal gland, p57Kip2 was expressed in the cortex but not in the medulla, whereas p27Kip1 was expressed in the medulla but not in the cortex. Whereas the expression of p57Kip2 in most tissues was restricted to embryogenesis, expression of p27Kip1 in many tissues was maintained in adult animals. Double-label immunofluorescence staining with either anti-p27Kip1 or anti-p57Kip2 and anti-BrdU revealed that the expression of p27Kip1 and p57Kip2 was inversely correlated with cell proliferation, suggesting that p27Kip1 and p57Kip2 are expressed exclusively in postmitotic cells. These complex spatial and temporal patterns of expression are consistent with the phenotypes of mice deficient in p27Kip1 or p57Kip2, and they suggest that these proteins might play important roles in tissue development.


Asunto(s)
Proteínas de Ciclo Celular , Desarrollo Embrionario y Fetal , Crecimiento , Proteínas Asociadas a Microtúbulos/análisis , Proteínas Nucleares/análisis , Proteínas Supresoras de Tumor , Corteza Suprarrenal/química , Médula Suprarrenal/química , Envejecimiento , Animales , Especificidad de Anticuerpos , Ciclo Celular , División Celular , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Inhibidor p57 de las Quinasas Dependientes de la Ciclina , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/deficiencia , Proteínas Asociadas a Microtúbulos/fisiología , Mitosis , Proteínas Nucleares/deficiencia , Proteínas Nucleares/fisiología , Especificidad de Órganos , Distribución Tisular
19.
Pharmacol Biochem Behav ; 35(2): 391-6, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2320647

RESUMEN

The effects of 24-hr fasting on the vertical (VMA) and horizontal (HMA) locomotor activities, on cage climbing activity and on brain monoamine-related substances, were examined using male ddY mice. Both the VMA and HMA increased with fasting, but not the cage climbing activity. Methamphetamine (2 mg/kg, SC) increased the VMA and HMA in both the feeding and fasting mice, whereas with apomorphine (0.1 mg/kg, SC) both decreased. Furthermore, pretreatment with haloperidol (0.025 mg/kg, SC) showed no influence on the methamphetamine-induced VMA increase in both the feeding and fasting mice. However, pretreatment with haloperidol inhibited the methamphetamine-induced HMA increase in both the feeding and fasting mice and showed a higher level of HMA in fasting mice than in feeding mice. When measuring brain monoamine-related substances, the DA, NE, 5-HT, and 5-HIAA levels in the corpus striatum increased, whereas the 3-MT levels decreased. The monoamine levels in the nucleus accumbens of fasting mice were the same as those in feeding mice, except for a decrease of the 3-MT level. These results suggest that the locomotor activity in fasting mice may be increased by a change in the sensitivity of dopaminergic neurons in the corpus striatum.


Asunto(s)
Apomorfina/farmacología , Monoaminas Biogénicas/metabolismo , Encéfalo/metabolismo , Ayuno/fisiología , Metanfetamina/farmacología , Actividad Motora/efectos de los fármacos , Animales , Cuerpo Estriado/metabolismo , Interacciones Farmacológicas , Haloperidol/farmacología , Masculino , Ratones , Actividad Motora/fisiología , Núcleo Accumbens/metabolismo
20.
Transplant Proc ; 36(8): 2432-5, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15561270

RESUMEN

Multiple-organ failure related to septicemia is a common cause of early mortality after liver transplantation. Endotoxemia following living donor hepatectomy may be a cause of postoperative death. Plasma fibronectin (Fn) exerts a broad range of biological effects on cellular adhesion, motility, differentiation, apoptosis, hemostasis, wound healing, reticuloendothelial system function, and ischemic injury. We studied the therapeutic effect of plasma Fn in mice after an intraperitoneal injection of lipopolysaccharide (LPS) and d-galactosamine (GalN). Female Balb/c mice received simultaneous intraperitoneal injection of LPS (50 microg/kg) and GalN (400 mg/kg). Thirty minutes prior to GalN/LPS administration, plasma Fn or bovine serum albumin was given intravenously. A single administration of plasma Fn (500 mg/kg) protected in dose-dependent fashion against lethal shock after GalN/LPS challenge. Plasma Fn significantly reduced the serum tumor necrosis factor-alpha, interferon-gamma, and interleukin-6 levels and significantly increased the serum interleukin-10 levels after GalN/LPS administration. Furthermore, plasma Fn significantly inhibited liver necrosis at 9 hours after GalN/LPS injection. The fraction of apoptotic-positive cells in these plasma Fn-treated mice was significantly lower than in the control group. These results support the protective treatment of endotoxin-induced liver injury by plasma Fn.


Asunto(s)
Apoptosis/efectos de los fármacos , Fibronectinas/uso terapéutico , Choque Séptico/prevención & control , Animales , Apoptosis/fisiología , Citocinas/sangre , Femenino , Humanos , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-6/sangre , Lipopolisacáridos , Fallo Hepático Agudo/inducido químicamente , Ratones , Ratones Endogámicos BALB C , Factor de Necrosis Tumoral alfa/metabolismo
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