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1.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(6 Pt 1): 061701, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20365179

RESUMEN

In this work, we will study the relative contribution of each of the two dissipative channels of the Eriksen, Leslie, and Parodi (ELP) approach to the observed values of the Miesowicz viscosity coefficients of the nematic liquid crystals. According to the fundamental equation of the liquid crystal's viscosity dissipative process, TS=-integral d3r(sigma)ijA(ij)+hxN , there are two channels by which the nematic viscous dissipation can occur: or it occurs by means of a shear flow configuration, where A(ij) is the characterizing term, or it occurs by means of a rotational configuration, where N is the characterizing term (these parameters will be defined in the paper). It will be also shown that this relative contribution can be measured by a simple relationship connecting the Miesowicz coefficients, which exhibits a quasitemperature independent behavior, suggesting that it is nearly constant through the entire domain of the nematic phase.


Asunto(s)
Cristales Líquidos/química , Modelos Químicos , Modelos Moleculares , Anisotropía , Simulación por Computador , Transferencia de Energía , Rotación
2.
J Neural Transm (Vienna) ; 114(5): 555-61, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17160370

RESUMEN

To investigate the relation between plasma amino acid levels and mental fatigue, we measured the plasma concentrations of 20 amino acids in 9 healthy volunteers before and after a fatigue-inducing mental task session for 8 hr. As fatigue-inducing mental tasks, the subjects performed an advanced trail making test, a Japanese KANA pick up test, and a mirror drawing test. As a control, 8-hr relaxation session was performed in the same subjects at an interval of 4 weeks. Immediately after the fatigue session, the plasma levels of branched-chain amino acids, tyrosine, cysteine, methionine, lysine, and arginine were below those after a relaxation session. The values for other blood parameters including total protein, albumin, glucose, and total cholesterol did not show any differences between the 2 sessions. These results indicate that mental fatigue may be characterized by a decrease in the plasma level of these amino acids.


Asunto(s)
Aminoácidos/sangre , Fatiga Mental/sangre , Fatiga Mental/fisiopatología , Adulto , Aminoácidos/análisis , Aminoácidos de Cadena Ramificada/análisis , Aminoácidos de Cadena Ramificada/sangre , Glucemia/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatología , Química Encefálica/fisiología , Colesterol/sangre , Regulación hacia Abajo/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Relajación/fisiología , Albúmina Sérica/metabolismo , Factores de Tiempo
3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(5 Pt 1): 051706, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16089550

RESUMEN

In this work, the effective viscosity of the cholesteryl myristate and cholesteryl nonanoate liquid crystals is studied as a function of temperature at the region of their cholesteric-to-isotropic phase transition, where blue phases are found. Using a change of scale it is shown that the viscosity peaks that characterize these phase transitions are shape invariant, which suggests that large-scale fluctuations on the two-point correlation function give an important contribution to the observed viscosity. The consequences of this fact are investigated and, from the experimental data, the critical exponents associated with the diverging two-point correlation function are calculated. The results found for both compounds are essentially the same, being also in good agreement with the known values of the corresponding critical exponents of nematic-isotropic phase transition.

4.
Int J Hematol ; 71(2): 167-71, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10745627

RESUMEN

A 30-year-old Japanese man with splenomegaly and lymphocytosis was examined in 1985. Blood analysis revealed that some of the lymphocytes had short-surface villi with polar distribution. The cells showed Ig lambda+, CD5+, CD11c+, CD19+, CD22+, CD23+, CD24+, FMC7+ phenotype. A small M peak was detected in the serum. Splenic lymphoma with villous lymphocytes (SLVL) was diagnosed on the basis of these findings. Remission was induced and was maintained with low-dose chlorambucil for more than 10 years. In 1996, the patient developed splenomegaly and lymphadenopathy with "B" symptoms and a high serum lactase dehydrogenase (LDH) level. Large blastoid cells with prominent nucleoli were observed in the bone marrow; later, a small number appeared in the peripheral blood. The bone marrow cells showed a complex chromosomal abnormality involving del(7)(q32). Southern blot analysis of immunoglobulin gene rearrangements in SLVL cells that had been cryopreserved in 1986 and of bone marrow cells in 1996 showed 2 rearranged bands in each cell sample; 1 band showed identical sizes in the 2 samples, and the other showed different sizes. These findings suggest that the blastoid cells were derived from SLVL cells through transformation. After this transformation, the disease followed a highly aggressive course. Various chemotherapeutic agents had little effect, and the patient died 3 months later.


Asunto(s)
Activación de Linfocitos , Linfoma/patología , Neoplasias del Bazo/patología , Adulto , Antígenos CD/sangre , Antineoplásicos/uso terapéutico , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/patología , Linaje de la Célula , Aberraciones Cromosómicas , Trastornos de los Cromosomas , Cromosomas Humanos Par 11 , Cromosomas Humanos Par 14 , Resultado Fatal , Humanos , Japón , Linfocitos/inmunología , Linfocitos/patología , Linfoma/tratamiento farmacológico , Linfoma/genética , Masculino , Neoplasias del Bazo/tratamiento farmacológico , Neoplasias del Bazo/genética , Translocación Genética
5.
Int J Mol Med ; 2(1): 51-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9854142

RESUMEN

Recently, we found a serum acylcarnitine (ACR) deficiency in Japanese patients with chronic fatigue syndrome (CFS). To clarify whether this ACR abnormality is a characteristic of CFS or not, we also studied the levels of serum carnitine in Swedish subjects. Both serum ACR and free carnitine (FCR) levels in normal healthy subjects were quite different between Japanese (n=131) and Swedish people (n=46) (p<0.001). However, it is confirmed that Swedish patients with CFS (n=57) also had serum ACR deficiency (p<0.001). When we studied the levels of serum ACR and FCR in Japanese patients with various kinds of diseases (CFS, hematological malignancies, chronic pancreatitis, hypertension, diabetes mellitus, chronic hepatitis type C, psychiatric diseases), a significant decrease in the levels of serum ACR was only found in patients with CFS and chronic hepatitis type C (p<0.001). Therefore, we concluded that ACR deficiency in serum might be a characteristic abnormality in only certain types of diseases.


Asunto(s)
Carnitina/análogos & derivados , Síndrome de Fatiga Crónica/sangre , Hepatitis C Crónica/sangre , Enfermedad Aguda , Animales , Carnitina/sangre , Carnitina/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Diabetes Mellitus/sangre , Diabetes Mellitus/etnología , Síndrome de Fatiga Crónica/etnología , Femenino , Galactosamina , Hepatitis C Crónica/etnología , Humanos , Japón , Masculino , Ratones , Ratones Endogámicos C3H , Neoplasias/sangre , Neoplasias/etnología , Suecia
6.
Int J Mol Med ; 1(1): 143-6, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9852212

RESUMEN

The chronic fatigue syndrome (CFS) is a condition of unknown etiology, characterized by a persistent debilitating fatigue, the muscle-related symptoms and the neuropsychiatric symptoms. Recently, it has been reported that the patients with CFS might have impaired activation of the hypothalamic-pituitary-adrenal axis, and suggested that a part of the patho-genesis of CFS might be associated with abnormalities of the endocrine system. Herein, we show that the majority of Japanese patients with CFS had a serum dehydroepiandrosterone sulfate (DHEA-S) deficiency. Serum DHEA-S is one of the most abundantly produced hormones which is secreted from the adrenal glands, and its physiological function is thought to be a precursor of sex steroids. DHEA-S has recently been shown to have physiological properties, such as neurosteroids, which are associated with such psychophysiological phenomena as memory, stress, anxiety, sleep and depression. Therefore, the deficiency of DHEA-S might be related to the neuropsychiatric symptoms in patients with CFS.


Asunto(s)
Sulfato de Deshidroepiandrosterona/sangre , Síndrome de Fatiga Crónica/sangre , 17-Hidroxicorticoesteroides/orina , 17-Cetosteroides/orina , Hormona Adrenocorticotrópica/sangre , Adulto , Deshidroepiandrosterona/sangre , Síndrome de Fatiga Crónica/fisiopatología , Síndrome de Fatiga Crónica/orina , Femenino , Humanos , Hidrocortisona/sangre , Masculino
7.
Am J Hematol ; 58(1): 55-60, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9590150

RESUMEN

The relationship between thrombocytopenia and the level of anticardiolipin antibodies (aCL) and/or the existence of lupus anticoagulant (LA) ware studied in 146 patients with systemic lupus erythematosus (SLE). These patients were divided into six groups: A, those LA positive with a high level of aCL (>10 U/ml) (10 cases); B, those LA positive with a low level of aCL (3-10 U/ml) (15 cases); C, those LA positive but aCL negative (<3 U/ml) (12 cases); D, LA negatives with a high level of aCL (12 cases); E, LA negatives with a low level of aCL (16 cases); and F, aCL and LA double negatives (81 cases). The prevalence of thrombocytopenia (platelet count < or = 100 x 10(9)L) was by far the highest in group A (9/10 cases, 90.0%, P < 0.005, Fisher's exact probability test) as compared with group B (4/15 cases, 26.7%), group C (4/12 cases, 33.3%), group D (1/12 cases, 8.3%), group E (4/16 cases, 25.5%), and group F (9/81 cases, 11.1%). When the relationship between moderate thrombocytopenia and arterial or venous thrombosis was studied in these patients with SLE, thrombocytopenia was detected in 10 (83.3%, P < 0.005, Fisher's exact probability test) of 12 patients with arterial thrombosis; however, it was present in only 4 (23.5%) of 17 patients with venous thrombosis and in 14 (12.3%) of 114 patients without thrombosis. These findings suggest that a high aCL activity combined with LA positively reflects a high risk for both thrombocytopenia and arterial thrombosis.


Asunto(s)
Anticuerpos Anticardiolipina/análisis , Inhibidor de Coagulación del Lupus/análisis , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/inmunología , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Adolescente , Adulto , Anciano , Arterias , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Valores de Referencia , Tromboflebitis/etiología , Trombosis/etiología
8.
Biochem Biophys Res Commun ; 231(2): 488-93, 1997 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-9070306

RESUMEN

The brain uptake of acetylcarnitine was investigated in rhesus monkeys using different position labeled acetyl-L-carnitine and related molecules with 11C by positron emission tomography. The uptake values of radio-labeled acetylcarnitine into the brain were quite different depending on the labeling positions of 11C. That is, the uptake values of L-[methyl-11C]carnitine and acetyl-L-[methyl-11C]carnitine were almost the same and extremely low, while the uptake of [1-11C]-acetyl-L-carnitine was slightly higher. The uptake value of [2-11C]acetyl-L-carnitine was by far the highest among the 11C-labeled acetyl-L-carnitine and L-carnitine. The uptake of [2-11C]acetyl-L-carnitine into the brain was suppressed by the intravenous administration of glucose. These results suggest that endogenous serum acetyl-L-carnitine has some roles on conveying an acetyl moiety into the brain especially under an energy crisis, and that an unknown metabolic pathway of [2-11C]acetyl moiety might be rather active in the brain.


Asunto(s)
Acetilcarnitina/farmacocinética , Encéfalo/metabolismo , Animales , Encéfalo/diagnóstico por imagen , Radioisótopos de Carbono , Ciclo del Ácido Cítrico , Macaca mulatta , Tomografía Computarizada de Emisión
9.
Biochem Biophys Res Commun ; 225(3): 740-6, 1996 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-8780683

RESUMEN

Carnitine metabolism during starvation and just after refeeding was studied by the measurement of acylcarnitine (ACR) and total carnitine (TCR) concentration in the serum and liver of mice. Starvation caused marked increases in the concentration of serum ACR, and of acid-soluble ACR in the liver. The refeeding caused the quick decrement of serum ACR with a concomitant marked increase in the level of acid-soluble TCR in the liver. Through the use of positron emission tomography in a rhesus monkey, a marked increase in [2-11C]acetyl-L-carnitine uptake in the liver was observed after the administration of glucose accompanying the decrease of serum ACR. From this study, it is clear that the mammalian liver can salvage and conserve the unused ACR when the state of energy metabolism is improved.


Asunto(s)
Carnitina/análisis , Carnitina/metabolismo , Ayuno/metabolismo , Acilación , Administración Oral , Adulto , Animales , Transporte Biológico Activo , Carnitina/sangre , Femenino , Glucosa/administración & dosificación , Humanos , Infusiones Intravenosas , Riñón/metabolismo , Hígado/metabolismo , Macaca mulatta , Masculino , Ratones , Ratones Endogámicos C3H , Tomografía Computarizada de Emisión
10.
Microbiol Immunol ; 40(6): 459-62, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8839433

RESUMEN

Borna disease virus (BDV) is a neurotropic, as yet unclassified, non-segmented, negative-sense, single-strand RNA virus. Natural infection with this virus has been reported to occur in horses and sheep. In addition, antibodies to BDV in plasma or BDV RNA in peripheral blood mononuclear cells (PBMCs) were also found in patients with neuropsychiatric diseases. We describe here the possible link between the patients with chronic fatigue syndrome (CFS) and infection with BDV.


Asunto(s)
Anticuerpos Antivirales/líquido cefalorraquídeo , Antígenos Virales/inmunología , Enfermedad de Borna/virología , Virus de la Enfermedad de Borna/aislamiento & purificación , Síndrome de Fatiga Crónica/virología , Proteínas Virales/inmunología , Adulto , Animales , Anticuerpos Antivirales/inmunología , Antígenos Virales/genética , Enfermedad de Borna/inmunología , Virus de la Enfermedad de Borna/genética , Virus de la Enfermedad de Borna/inmunología , Síndrome de Fatiga Crónica/líquido cefalorraquídeo , Síndrome de Fatiga Crónica/inmunología , Humanos , Japón , ARN Viral/líquido cefalorraquídeo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Virales/genética
11.
Clin Infect Dis ; 18 Suppl 1: S62-7, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8148455

RESUMEN

One of the characteristic complaints of patients with chronic fatigue syndrome (CFS) is the skeletal muscle-related symptom. However, the abnormalities in the skeletal muscle that explain the symptom are not clear. Herein, we show that our patients with CFS had a deficiency of serum acylcarnitine. As carnitine has an important role in energy production and modulation of the intramitochondrial coenzyme A (CoA)/acyl-CoA ratio in the skeletal muscle, this deficiency might induce an energy deficit and/or abnormality of the intramitochondrial condition in the skeletal muscle, thus resulting in general fatigue, myalgia, muscle weakness, and postexertional malaise in patients with CFS. Furthermore, the concentration of serum acylcarnitine in patients with CFS tended to increase to the normal level with the recovery of general fatigue. Therefore, the measurement of acylcarnitine would be a useful tool for the diagnosis and assessment of the degree of clinical manifestation in patients with CFS.


Asunto(s)
Carnitina/análogos & derivados , Carnitina/deficiencia , Síndrome de Fatiga Crónica/metabolismo , Acilcoenzima A/metabolismo , Carnitina/sangre , Coenzima A/metabolismo , Metabolismo Energético , Síndrome de Fatiga Crónica/sangre , Síndrome de Fatiga Crónica/diagnóstico , Femenino , Humanos , Membranas Intracelulares/metabolismo , Masculino , Mitocondrias Musculares/metabolismo , Músculos/metabolismo
12.
Nihon Rinsho ; 50(11): 2665-72, 1992 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-1337562

RESUMEN

This review summarizes the symptoms, signs and laboratory abnormalities seen in 59 patients with chronic fatigue syndrome (CFS), 2 patients with post-infectious CFS and in 26 patients with possible CFS whose illnesses fulfill the criteria proposed by the study group of the Ministry of Welfare, Japan. The characteristic symptoms and signs of CFS are prolonged generalized fatigue following exercise, headache, neuropsychological symptoms, sleep disturbance and mild fever. In possible CFS patients, the frequency of mild fever, muscle weakness, myalgia and headache is low. Our standard hematologic and laboratory tests revealed a few abnormality in patients with CFS. The characteristic abnormality in CFS patients is the low values of 17-Ketosteroid-Sulfates/creatinine in morning urine and the acylcarnitine deficiency. It seems likely that this deficiency of acylcarnitine induces an energy deficit in the skeletal muscle, resulting in general fatigue, myalgia, muscle weakness and postexertional malaise in CFS patients. Virologic studies revealed no evidence of retrovirus infection with HTLV-1, HTLV-2 and HIV, but the reactivation of HHV-6 infection was apparent.


Asunto(s)
Síndrome de Fatiga Crónica/diagnóstico , Adolescente , Adulto , Anticuerpos Antivirales/análisis , Síndrome de Fatiga Crónica/etiología , Síndrome de Fatiga Crónica/fisiopatología , Femenino , Fiebre , Cefalea , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/diagnóstico , Herpesvirus Humano 4/inmunología , Humanos , Inmunoglobulina G/análisis , Linfadenitis , Masculino , Persona de Mediana Edad , Estrés Psicológico/complicaciones
13.
Nihon Kyosei Shika Gakkai Zasshi ; 49(2): 132-9, 1990 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-2133871

RESUMEN

The present investigation has been attempted to clarify the remodeling mechanisms of transseptal fibers during mechanical retention periods. Orthodontic forces of 25 gm and 150 gm were respectively applied to upper molars of rats for 10 days and retained mechanically. Retention periods were 10, 30 and 60 days. The trend of transseptal fibers after these retention periods was observed by the methods of histology and histochemistry. Histological study was observed rearrangement of fibrous tissue by light and electron microscopy and histochemical one was observed acid phosphatase activity. The following results were obtained: 1. Very little was observed about the rearrangement of transseptal fibers by the orthodontic force applied for 10 days. 2. The mechanical retention was kept longer, stretched transseptal fibers were slowly restored to original shape. This means transseptal fibers were gradually rearranged. 3. The collagen containing fibroblast and fibroblast characterized by abundant rough endoplasmic reticulum and Golgi complex were ultrastructurally observed. 4. The reaction of ACPase activity in some fibroblasts can be observed. These results suggest that transseptal fibers were rearranged during mechanical retention periods and that fibroblasts were engaged in this remodeling by synthesizing and degrading collagen fibers.


Asunto(s)
Ortodoncia Correctiva , Ligamento Periodontal/fisiología , Animales , Colágeno/metabolismo , Análisis del Estrés Dental , Fibroblastos/ultraestructura , Ligamento Periodontal/anatomía & histología , Ratas
14.
Shoni Shikagaku Zasshi ; 27(2): 529-36, 1989.
Artículo en Japonés | MEDLINE | ID: mdl-2489388

RESUMEN

The two cases with the transposition of the teeth were treated orthodontically. One was a case in which the teeth which had changed places with each other were aligned in irregular sequence, the other was one with the teeth which had erupted at the unusual position were repositioned in order of the tooth number. Those causes and some problems involved in diagnosis and treatment were discussed. 1. The causes of transposition of the teeth in the two cases reported herein seemed to be premature loss of primary teeth and the malposition of permanent tooth germs, respectively. 2. At the time of the planning of the treatment, the following must be considered. 1) Perfect transposition or imperfect. 2) The positions of root apexes and axial inclinations of the teeth irregularly erupted. 3. Root paralleling is most important for the stability of the treatment results. Moreover, in case of unusual alignment, prevention of premature contact in jaw movement and improvement of appearance must be endeavored.


Asunto(s)
Ortodoncia Correctiva , Erupción Ectópica de Dientes/terapia , Humanos
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