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1.
J Dairy Sci ; 105(4): 2978-2987, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35086716

RESUMEN

Extended shelf life (ESL) processing (i.e., heat treatment at 130°C for 2 s) is usually not used for producing set yogurt because of the fragility of the curd structure. We investigated the effects of homogenization conducted at higher pressure than the conventional conditions (10 MPa for the first stage and 5 MPa for the second stage) on the curd structure of set yogurt, with a focus on the fat globule size. Each yogurt mix was adjusted at the range of fat globule sizes from 0.45 µm to 1.1 µm by a homogenizer and then heated at 95°C for 5 min (conventional heat treatment), 120°C for 2 s, ESL processing, or 140°C for 2 s. The yogurt mixes were fermented by a common yogurt starter, and the curd texture of the obtained yogurts was evaluated. We observed that the curd hardness and curd firmness of the yogurt were each negatively correlated with the fat globule size regardless of the heat-treatment temperature. Compared with the curd obtained with conventional heat treatment, the ESL-processed curd was extremely fragile, but significantly smooth. With ESL processing, a curd hardness >40 g, which is a sufficient strength for commercial transport systems, was obtained by making the fat particle size <0.6 µm, using 2-stage homogenization pressure: 35 MPa for the first stage and 5 MPa for the second stage. A microscopy analysis indicated that the smaller fat globules reinforce the network structure. The yogurt made by ESL processing and that created with 35 + 5 MPa homogenization had significant sensory evaluation scores. Our results indicate that the combination of ESL processing and 35 + 5 MPa homogenization is a novel and useful method for manufacturing set yogurt.


Asunto(s)
Calor , Yogur , Animales , Manipulación de Alimentos/métodos , Temperatura , Yogur/análisis
2.
Skin Res Technol ; 21(2): 224-31, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25156803

RESUMEN

BACKGROUND/PURPOSE: In the past, it has been possible to measure the dermal papilla structures which are undulations between the epidermis and dermis by noninvasive method. However, almost all of previous studies were not intended to measure facial skin but another site of body. Here, we investigated age-dependent alterations for dermal papilla structures in the facial cheek region after elucidating the difference of characteristics between the body site. METHODS: The surface of the dermis was observed under scanning electron microscope (SEM) using face and abdominal skin biopsy samples. A total of 90 Japanese women were investigated by in vivo confocal laser microscope (CLSM). The number and the shape in the horizontal cross-sectional images of the dermal papilla were analyzed. RESULTS: The facial skin had different characteristics in comparison to the abdominal skin by SEM observation. Under CLSM observation, we found abnormal dermal papilla structures which were accompanied by spots or enlarged pore areas and eliminated these structures from our analysis. We revealed a decrease in the number of normal dermal papilla structures with age and large individual differences at younger ages. CONCLUSION: We found abnormal dermal papilla structures and differences in the dermal papilla structures between face and other body site. With these taken into consideration, we could precisely investigate the aging alteration of normal dermal papilla structures in the face.


Asunto(s)
Mejilla/anatomía & histología , Mejilla/fisiología , Dermis/fisiología , Dermis/ultraestructura , Envejecimiento de la Piel/fisiología , Piel/ultraestructura , Adulto , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
3.
Oper Dent ; 48(5): 483-489, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37503684

RESUMEN

Direct composite restorations are accepted as a treatment option for microdontia, which is a relatively prevalent condition that poses esthetic concerns. While free-hand composite placement is technique-sensitive and time-consuming, the resin composite injection technique is more straightforward and predictable. A fully digital workflow has been recently introduced, but the 3D-printed resin index is rigid and challenged by undercuts, as opposed to the silicone index. This case report presents a flexible 3D-printed resin index, which can accurately transfer the digitally simulated functional and esthetic form to the final restoration. In addition, a rigid stabilization holder was designed to stabilize the flexible index.


Asunto(s)
Resinas Compuestas , Estética Dental , Humanos , Flujo de Trabajo , Resinas Compuestas/uso terapéutico , Siliconas , Impresión Tridimensional
4.
Science ; 290(5499): 2148-52, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11118149

RESUMEN

The growth of the bacterial flagellar filament occurs at its distal end by self-assembly of flagellin transported from the cytoplasm through the narrow central channel. The cap at the growing end is essential for its growth, remaining stably attached while permitting the flagellin insertion. In order to understand the assembly mechanism, we used electron microscopy to study the structures of the cap-filament complex and isolated cap dimer. Five leg-like anchor domains of the pentameric cap flexibly adjusted their conformations to keep just one flagellin binding site open, indicating a cap rotation mechanism to promote the flagellin self-assembly. This represents one of the most dynamic movements in protein structures.


Asunto(s)
Bacterias/ultraestructura , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Flagelos/metabolismo , Flagelina/química , Flagelina/metabolismo , Bacterias/metabolismo , Microscopía por Crioelectrón , Difusión , Dimerización , Flagelos/ultraestructura , Procesamiento de Imagen Asistido por Computador , Modelos Biológicos , Conformación Proteica , Pliegue de Proteína , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína
5.
Bone Marrow Transplant ; 41(12): 1029-35, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18332910

RESUMEN

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has proven effective in adult T-cell leukemia/lymphoma (ATL) patients. To study the graft-versus-ATL (Gv-ATL) effects after allo-HSCT, we analyzed 21 ATL patients who had been treated at our hospital. Of these, 18 had acute-, 2 had lymphoma- and 1 had chronic-type ATL; at allo-HSCT, seven patients were in CR, one was in PR, five had stable disease (SD) and eight had progressive disease (PD). Disease state after allo-HSCT was CR in 14, PR in 3, SD in 1 and PD in 3 patients. Among 15 patients who survived longer than 100 days, ATL relapsed in 10 patients, skin relapsed in 9 patients and 5 had relapsed on the skin alone. After we discontinued immunosuppressant therapy in these 10 patients, 8 manifested GVHD; ATL was ameliorated to CR in 6 patients. Donor lymphocytes were infused into two patients who did not show GVHD; one obtained CR. In five patients with skin relapse alone, four patients achieved CR following the discontinuation of the immunosuppressants. Our results demonstrate that relapse of ATL after allo-HSCT tends to develop on skin, and Gv-ATL effects played a critical role in the outcome of allo-HSCT for ATL.


Asunto(s)
Efecto Injerto vs Leucemia , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia-Linfoma de Células T del Adulto/terapia , Adulto , Estudios de Cohortes , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Estimación de Kaplan-Meier , Leucemia-Linfoma de Células T del Adulto/patología , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Enfermedades de la Piel/patología , Trasplante Homólogo
6.
Circ Res ; 89(7): 591-8, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11577024

RESUMEN

Physiological and pathological cardiac hypertrophy have directionally opposite changes in transcription of thyroid hormone (TH)-responsive genes, including alpha- and beta-myosin heavy chain (MyHC) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA), and TH treatment can reverse molecular and functional abnormalities in pathological hypertrophy, such as pressure overload. These findings suggest relative hypothyroidism in pathological hypertrophy, but serum levels of TH are usually normal. We studied the regulation of TH receptors (TRs) beta1, alpha1, and alpha2 in pathological and physiological rat cardiac hypertrophy models with hypothyroid- and hyperthyroid-like changes in the TH target genes, alpha- and beta-MyHC and SERCA. All 3 TR subtypes in myocytes were downregulated in 2 hypertrophy models with a hypothyroid-like mRNA phenotype, phenylephrine in culture and pressure overload in vivo. Myocyte TRbeta1 was upregulated in models with a hyperthyroid-like phenotype, TH (triiodothyronine, T3), in culture and exercise in vivo. In myocyte culture, TR overexpression, or excess T3, reversed the effects of phenylephrine on TH-responsive mRNAs and promoters. In addition, TR cotransfection and treatment with the TRbeta1-selective agonist GC-1 suggested different functional coupling of the TR isoforms, TRbeta1 to transcription of beta-MyHC, SERCA, and TRbeta1, and TRalpha1 to alpha-MyHC transcription and increased myocyte size. We conclude that TR isoforms have distinct regulation and function in rat cardiac myocytes. Changes in myocyte TR levels can explain in part the characteristic molecular phenotypes in physiological and pathological cardiac hypertrophy.


Asunto(s)
Cardiomegalia/fisiopatología , Regulación de la Expresión Génica , Miocardio/metabolismo , Receptores de Hormona Tiroidea/genética , Receptores de Hormona Tiroidea/metabolismo , Animales , ATPasas Transportadoras de Calcio/genética , ATPasas Transportadoras de Calcio/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Actividad Motora , Miocardio/citología , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Fenotipo , Fenilefrina/farmacología , Condicionamiento Físico Animal , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptores de Hormona Tiroidea/agonistas , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico , Transfección , Triyodotironina/farmacología
7.
Circulation ; 101(18): 2134-7, 2000 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-10801751

RESUMEN

BACKGROUND: Calcineurin may play a pivotal role in the signaling of cardiac hypertrophy; since this hypothesis was first put forward, controversial reports have been published using various experimental models. This study was designed to compare the physiological left ventricular hypertrophy (LVH) induced by voluntary exercise with LVH induced by aortic constriction and to determine whether calcineurin participates in the signaling of exercise-induced LVH. METHODS AND RESULTS: Wistar rats were assigned to 1 of the following 5 groups: 10 weeks of voluntary exercise (EX), a sedentary regimen, a 1-week (AC1) or 4-week (AC4) ascending aortic constriction period, or a sham operation. EX rats ran 2.4+/-0.7 km/day voluntarily in specially manufactured cages; this was associated with an increase of LV diastolic dimension and stroke volume. Myocardial calcineurin activity markedly increased in EX rats (46.4+/-8.3 versus 18.4+/-0.5 pmol. min(-1). mg(-1) in sedentary rats; P<0.001) and in AC1 rats (44.9+/-6.7 versus 22.1+/-3.7 pmol. min(-1). mg(-1) in sham-operated rats; P<0.001), but not in AC4 rats (29.0+/-3.4 pmol. min(-1). mg(-1)). Treatment with cyclosporin A completely inhibited the development of LVH in EX rats, but it only partially attenuated the development of LVH in AC4 rats. CONCLUSIONS: Calcineurin was activated in exercise-induced physiological LVH and in the developing phase of LVH (AC1), but not in decompensated pressure-overload hypertrophy (AC4). Cyclosporin therapy for the prevention of LVH may be harmful because it does not block the development of pathological hypertrophy but rather that of favorable adaptive hypertrophy.


Asunto(s)
Calcineurina/fisiología , Hipertrofia Ventricular Izquierda/metabolismo , Condicionamiento Físico Animal/fisiología , Animales , Hipertrofia Ventricular Izquierda/fisiopatología , Ratas , Transducción de Señal
8.
Circulation ; 100(2): 117-22, 1999 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-10402439

RESUMEN

BACKGROUND: Diminished myocardial vasodilatation (MVD) in hypercholesterolemics without overt coronary stenosis has been reported. However, whether the diminished MVD of angiographically normal coronary arteries in hypercholesterolemics can be reversed after lipid-lowering therapy is not known. METHODS AND RESULTS: A total of 27 hypercholesterolemics and 16 age-matched controls were studied. All patients had >1 normal coronary artery, and those segments that were perfused by anatomically normal coronary arteries were studied. Myocardial blood flow (MBF) was measured during dipyridamole loading and at baseline using positron emission tomography and 13N-ammonia, after which MVD was calculated before and after lipid-lowering therapy. Total cholesterol was significantly higher in hypercholesterolemics (263+/-33.8) than in controls (195+/-16.6), and it normalized after lipid-lowering therapy (197+/-19.9). Baseline MBF (ml. min-1. 100 g-1) was comparable among hypercholesterolemics (both before and after therapy) and controls. MBF during dipyridamole loading was significantly lower in hypercholesterolemics before therapy (189+/-75.4) than in controls (299+/-162, P<0.01). However, MBF during dipyridamole loading significantly increased after therapy (226+/-84.7; P<0.01). MVD significantly improved after therapy in hypercholesterolemics (2.77+/-1.35 after treatment [P<0.05] versus 2. 02+/-0.68 before treatment [P<0.01]), but it remained significantly higher in controls (3.69+/-1.13, P<0.01). There was a significant relationship between the percent change of total cholesterol and the percent change of MVD before and after lipid-lowering therapy (r=-0. 61, P<0.05). CONCLUSIONS: Diminished MVD of anatomically normal coronary arteries in hypercholesterolemics can be reversed after lipid-lowering therapy.


Asunto(s)
Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Hipercolesterolemia/complicaciones , Hipercolesterolemia/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Vasodilatación/fisiología , Anciano , Circulación Coronaria/efectos de los fármacos , Circulación Coronaria/fisiología , Diabetes Mellitus/fisiopatología , Dipiridamol/farmacología , Electrocardiografía , Femenino , Hemodinámica/fisiología , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Vasodilatadores/farmacología
9.
Cell Death Differ ; 10(3): 313-22, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12700631

RESUMEN

Interferon-gamma (IFN-gamma) induced cell death in five oral squamous cell carcinoma (SCC) lines. Cell death was specific to IFN-gamma treatment and did not occur with either IFN-alpha or TNF-alpha. IFN-gamma did not induce typical apoptotic phenotype in cells, such as morphological changes and DNA ladder formation. Caspase-3 was partially activated by IFN-gamma. Protein levels of molecular chaperones were examined in cells treated with IFN-gamma. Among these, levels of heat shock protein 27 (Hsp27) were specifically reduced upon IFN-gamma treatment of oral SCC cells. Recombinant clones overexpressing Hsp27 were more resistant to IFN-gamma-induced cell death than parent cells. Conversely, cells expressing a dominant-negative mutant of Hsp27, in which three serine residues (15, 78 and 82) were replaced by glycine, were hypersensitive to the effects of IFN-gamma and exhibited a typical apoptotic phenotype. Pretreatment of cells with IFN-gamma enhanced apoptotic cell death induced by cisplatin. Our data suggest that IFN-gamma suppresses Hsp27 expression in oral SCC cells and blocks the inhibitory effects of this molecular chaperone on apoptotic cell death. Moreover, IFN-gamma initiates the transition of oral SCC cells to the proapoptotic and/or aborted apoptotic state. Hsp27 plays a crucial role in the inhibition of apoptosis of oral SCC cells. Our findings highlight the importance of employing IFN-gamma in combination with certain anticancer drugs as treatments for oral cancer. We suggest that Hsp27 plays a significant role in the IFN-gamma-induced sensitization of oral SCC cells to anticancer drugs.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Proteínas de Choque Térmico , Interferón gamma/fisiología , Proteínas de Neoplasias/biosíntesis , Antineoplásicos/farmacología , Apoptosis , Western Blotting , Caspasa 3 , Caspasas/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Cromatografía en Gel , Cisplatino/farmacología , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Genes Dominantes , Proteínas de Choque Térmico HSP27 , Humanos , Interferón gamma/biosíntesis , Interferón gamma/metabolismo , Microscopía Electrónica , Chaperonas Moleculares/metabolismo , Neoplasias de la Boca/metabolismo , Mutación , Fenotipo , Plásmidos/metabolismo , Factores de Tiempo
10.
Diabetes ; 47(1): 119-24, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9421384

RESUMEN

To clarify if coronary flow reserve (CFR) is related to insulin resistance or hyperglycemia in normotensive NIDDM, myocardial blood flow (MBF) at baseline and during dipyridamole loading were measured with 13N-ammonia positron-emission tomography. CFR was significantly reduced in NIDDM patients compared with age-matched control subjects. CFR in patients with well-controlled NIDDM was significantly higher than in those with poorly controlled NIDDM, whereas insulin resistance was comparable between the two groups. CFR in NIDDM patients was not related to the degree of insulin resistance. CFR correlated significantly with average fasting glucose concentration and average HbA1c, but not with insulin resistance, age, lipid parameters, or blood pressure. In conclusion, control of blood glucose concentration rather than insulin resistance is most likely related to the reduced CFR in NIDDM.


Asunto(s)
Vasos Coronarios/fisiología , Diabetes Mellitus Tipo 2/fisiopatología , Hiperglucemia/fisiopatología , Resistencia a la Insulina/fisiología , Adulto , Anciano , Glucemia/análisis , Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 2/sangre , Dipiridamol/farmacología , Electrocardiografía , Femenino , Hemoglobina Glucada/análisis , Hemodinámica , Humanos , Hiperglucemia/sangre , Insulina/sangre , Lípidos/sangre , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional/fisiología , Tomografía Computarizada de Emisión
11.
J Am Coll Cardiol ; 31(7): 1568-74, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9626836

RESUMEN

OBJECTIVES: This study sought to investigate the specific role of hypertriglyceridemia in the myocardial hyperemic stress with dipyridamole/rest flow ratio (MDR). BACKGROUND: Reduced MDR has been reported in hypercholesterolemic patients without evidence of ischemia. However, the specific role of hypertriglyceridemia in MDR has not been studied. METHODS: Fifteen nondiabetic normocholesterolemic hypertriglyceridemic patients and 13 age-matched control subjects were studied. Myocardial blood flow (MBF) during dipyridamole administration and baseline MBF in hypertriglyceridemic patients and control subjects were measured using positron emission tomography and nitrogen-13 ammonia, after which the MDR was calculated. RESULTS: Baseline MBF (ml/min per 100 g heart weight) in hypertriglyceridemic patients (mean +/- SD 73.6 +/- 24.1) did not differ significantly from that in control subjects (81.6 +/- 37.2). MBF during dipyridamole loading in hypertriglyceridemic patients (198 +/- 106) was significantly reduced compared with that in control subjects (313 +/- 176, p < 0.05), as was the MDR (2.71 +/- 1.07 vs. 3.73 +/- 1.14, respectively, p < 0.05). Spearman rank-order correlation analysis showed a significant relation between plasma triglyceride concentration and MDR (r = -0.466, asymptotic SE 0.157, p = 0.0125); however, no such significant relation was seen between total plasma cholesterol concentration and MDR (r = -0.369, asymptotic SE 0.130, p = 0.059). CONCLUSIONS: Impaired myocardial vasodilation was suggested in hypertriglyceridemic patients without symptoms and signs of ischemia.


Asunto(s)
Circulación Coronaria , Corazón/fisiopatología , Hiperemia/fisiopatología , Hipertrigliceridemia/fisiopatología , Adulto , Dipiridamol , Electrocardiografía , Prueba de Esfuerzo , Femenino , Pruebas de Función Cardíaca , Hemodinámica , Humanos , Hipertrigliceridemia/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión , Vasodilatación , Vasodilatadores
12.
J Am Coll Cardiol ; 30(6): 1472-7, 1997 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-9362404

RESUMEN

OBJECTIVES: We analyzed myocardial flow reserve (MFR) in patients with non-insulin-dependent (type II) diabetes mellitus (NIDDM) without symptoms and signs of ischemia. BACKGROUND: Diminished MFR in diabetes has been suggested. However, it remains controversial whether MFR is related to glycemic control, mode of therapy or gender in NIDDM. METHODS: Myocardial blood flow (MBF) was measured at baseline and during dipyridamole loading in 25 asymptomatic, normotensive, normocholesterolemic patients with NIDDM and 12 age-matched control subjects by means of positron emission tomography and nitrogen-13 ammonia, after which MFR was calculated. RESULTS: Baseline MBF in patients with NIDDM ([mean +/- SD] 74.0 +/- 24.0 ml/min per 100 g body weight) was comparable to that in control subjects (73.0 +/- 17.0 ml/min per 100 g). However, MBF during dipyridamole loading was significantly lower in patients with NIDDM (184 +/- 99.0 ml/min per 100 g, p < 0.01) than in control subjects (262 +/- 120 ml/min per 100 g), as was MFR (NIDDM: 2.77 +/- 0.85; control subjects: 3.8 +/- 1.0, p < 0.01). A significantly decreased MFR was seen in men (2.35 +/- 0.84) compared with women with NIDDM (3.18 +/- 0.79, p < 0.05); however, no significant differences were found in terms of age, hemoglobin a1c and baseline MBF. MFR was comparable between the diet (2.78 +/- 0.80) and medication therapy groups (2.76 +/- 0.77) and was inversely correlated with average hemoglobin A1c for 5 years (r = -0.55, p < 0.01) and fasting plasma glucose concentration (r = -0.57, p < 0.01) but not age or lipid fractions. CONCLUSIONS: Glycemic control and gender, rather than mode of therapy, is related to MFR in NIDDM.


Asunto(s)
Circulación Coronaria , Diabetes Mellitus Tipo 2/fisiopatología , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Cardiovasculares , Factores Sexuales
13.
J Mol Biol ; 249(1): 69-87, 1995 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-7776377

RESUMEN

The supercoiled forms of the flagellar filaments are thought to be constructed from a mixture of two distinct subunit conformations arranged in a regular manner. We analyzed the structure of one of the two straight flagellar filaments, each of which is built up with all its subunits in one of the two conformations. The filament we studied was isolated from the strain SJW1655 of Salmonella typhimurium and had a right-handed helical symmetry. With recent advancements in electron cryomicroscopy, such as a liquid helium temperature stage for frozen hydrated specimens and a stable field emission source, and also by averaging high resolution data with a proper correction of the contrast transfer function, the density distribution map of this straight flagellar filament was generated in far more detail than before by including data up to 9 A resolution. The structure shows a densely packed core region from about 15 to 55 A in radius, where a pair of concentric tubular features of high density is present without well-defined subunit boundaries, and an outer part from 55 to 115 A, where the subunits are mostly well separated from each other. The outer tube in the core region, from 35 to 55 A in radius, contains many rod-like features with near-axial orientation and closest lateral distances of around 10 A, which are most likely to represent the alpha-helical bundles that were predicted in our previous report. In the inner tube, from 15 to 30 A in radius, the rod-like features are less clear. Between the inner and outer tubes are the short spoke-like densities, which are radially tilted and are connecting the two tubes. The outer part, from 55 to 115 A, contains an axially elongated column density and a slewed projection with a narrow neck region. When compared with the other straight filament having left-handed helical symmetry, this outer part does not show any significant changes in orientation, suggesting that the switch in the subunit conformation and packing involved in the polymorphic transitions is quite subtle and only occurs within the core region. Reassignment of each structural domain to the amino acid sequence is suggested, based on the volume of each domain, which was determined rather precisely by a proper correction of the contrast transfer function for both amplitudes and phases.


Asunto(s)
Flagelos/ultraestructura , Salmonella typhimurium/ultraestructura , Proteínas Bacterianas/ultraestructura , Crioultramicrotomía , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica , Estructura Secundaria de Proteína
14.
Clin Cancer Res ; 5(8): 2185-91, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10473104

RESUMEN

UFT, an anticancer agent that is composed of tegafur (FT) and uracil at a molar ratio of 1:4, is widely used in clinical practice in Japan to treat cancer patients requiring a long-term chemotherapy, and it is associated with few side effects, if any. In this study, we have evaluated the inhibitory effect of UFT against RENCA cell-induced angiogenesis by a dorsal air sac assay. Marked angiogenesis is induced by implantation of a chamber containing RENCA cells into mice. In this model, UFT showed a strong angiogenesis-inhibitory effect, whereas 5-fluorouracil (5-FU) and doxifluridine were less effective. Additional experiments revealed FT to be effective component of UFT; uracil remained ineffective in the inhibition of angiogenesis. Moreover, we have found that gamma-hydroxybutyric acid and gamma-butyrolactone, the metabolites of FT, possess a potent angiogenesis inhibitory effect that is amplified when the compounds are administered by a continuous infusion. This may reflect a transition in blood concentration of each metabolite resulting from the administration of UFT. Similar results were also obtained with respect to 5-FU. It was suggested that UFT has a stronger angiogenesis-inhibitory effect than did other fluorinated pyrimidines, partly due to its pharmacokinetic properties characterized by maintaining of higher and long-lasting blood levels of 5-FU and partly due the inhibitory effects derived from gamma-hydroxybutyric acid and gamma-butyrolactone, UFT-specific metabolites.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Renales/irrigación sanguínea , Neoplasias Renales/irrigación sanguínea , Neovascularización Patológica/tratamiento farmacológico , 4-Butirolactona/uso terapéutico , Animales , División Celular/efectos de los fármacos , Cámaras de Difusión de Cultivos , Relación Dosis-Respuesta a Droga , Floxuridina/uso terapéutico , Fluorouracilo/uso terapéutico , Hidroxibutiratos/uso terapéutico , Masculino , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Tegafur/uso terapéutico , Células Tumorales Cultivadas , Uracilo/uso terapéutico
15.
Clin Exp Metastasis ; 16(7): 633-43, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9932610

RESUMEN

We examined the in vivo anti-tumor activity of the benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl)benzamido] benzoic acid), for intrahepatic spread of JHH-7 human hepatocellular carcinoma (HCC) cells and its mechanism of action. Oral administration of TAC-101 markedly inhibited liver tumor of JHH-7 cells and prolonged the life-span of tumor-bearing mice without affecting the body weight. The life-prolonging effect of TAC-101 was more effective than that of other anti-cancer agents including CDDP, 5-FU, and CPT-11 (T/C (%) of life-span; 181 to 219, 128, 133, and 142%, respectively). In vitro, TAC-101 at the concentration of more than 10 microM showed direct cytotoxicity against JHH-7 cells caused by induction of apoptosis. Hepatocyte growth factor (HGF) enhanced the invasive ability of JHH-7 cells without affecting the cell viability. Non-cytotoxic concentrations of TAC-101 inhibited the JHH-7 invasion induced by HGF and down-regulated the expression of c-MET protein in a concentration-dependent manner. In summary, these results suggest that TAC-101 would be useful for a new class of therapeutic agents and that it may improve the prognosis of patients with liver-tumors including metastasizing tumor and HCC.


Asunto(s)
Antineoplásicos/farmacología , Benzoatos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Invasividad Neoplásica/prevención & control , Compuestos de Trimetilsililo/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Benzoatos/toxicidad , Peso Corporal/efectos de los fármacos , Camptotecina/análogos & derivados , Camptotecina/farmacología , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Fluorouracilo/farmacología , Humanos , Irinotecán , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/mortalidad , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Desnudos , Estructura Molecular , Proteínas Proto-Oncogénicas c-met/metabolismo , Receptores de Ácido Retinoico/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Organismos Libres de Patógenos Específicos , Tasa de Supervivencia , Compuestos de Trimetilsililo/toxicidad , Células Tumorales Cultivadas
16.
Clin Exp Metastasis ; 16(4): 323-31, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9626811

RESUMEN

We examined the anti-tumor effect of a novel benzoic acid derivative, TAC-101 (4-[3,5-bis(trimethylsilyl) benzamide] benzoic acid) on models with liver metastasis. Oral administration of TAC-101 significantly inhibited spontaneous liver metastasis of AZ-521 (human gastric cancer ) by orthotopic implantation to athymic nude mice. It also inhibited both the liver metastasis of AZ-521 induced by intrasplenic injection and the secondary lung metastasis from the liver. In addition, TAC-101 inhibited the proliferation of Co-3 (human colon adenocarcinoma) that formed a single nodule in the liver of athymic nude mice by intrahepatic implantation. The growth inhibitory effect of TAC-101 on AZ-521 experimental liver metastasis was observed when treatment was started on day 7, 14, or 21 which may correspond to the progressive stage of liver metastasis in clinical settings. Multiple administration of TAC-101 (8 mg/kg/day) significantly prolonged survival time of the animals with liver metastasis by intrasplenic injection of AZ-521 (T/C = 230%) and A549 (human lung adenocarcinoma; T/C = 186%). These effects of TAC-101 were stronger than those of 5-FU, CDDP or ATRA. Furthermore, TAC-101 inhibited the binding of AP-1 to DNA on electrophoretic mobility shift assay using nuclear extract of AZ-521 cells, although ATRA did not inhibit. These findings suggested that TAC-101 may be a candidate for a new class of anti-cancer agents for liver metastasis.


Asunto(s)
Adenocarcinoma/patología , Antineoplásicos/farmacología , Benzoatos/farmacología , Benzoatos/uso terapéutico , Neoplasias Gastrointestinales/patología , Neoplasias Hepáticas Experimentales/prevención & control , Neoplasias Hepáticas Experimentales/secundario , Compuestos de Trimetilsililo/uso terapéutico , Adenocarcinoma/mortalidad , Adenocarcinoma/prevención & control , Animales , Antineoplásicos/administración & dosificación , División Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Neoplasias del Colon/patología , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/metabolismo , Esquema de Medicación , Humanos , Neoplasias Hepáticas Experimentales/mortalidad , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Experimentales/prevención & control , Neoplasias Experimentales/secundario , Neoplasias del Bazo/mortalidad , Neoplasias del Bazo/prevención & control , Neoplasias del Bazo/secundario , Análisis de Supervivencia , Factor de Transcripción AP-1/antagonistas & inhibidores , Factor de Transcripción AP-1/metabolismo , Células Tumorales Cultivadas
17.
J Nucl Med ; 39(5): 884-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9591594

RESUMEN

UNLABELLED: Abnormal heart and skeletal muscle glucose metabolism in diabetes or essential hypertension has been demonstrated. However, the role of hypertension in heart and skeletal muscle glucose utilization in diabetes has not been clarified yet. METHODS: We compared heart and skeletal muscle glucose utilization using PET and the whole-body glucose disposal rate (GDR) during insulin clamping in 9 patients with noninsulin-dependent diabetes mellitus (NIDDM) and essential hypertension and 11 patients with NIDDM without hypertension to examine the effect of hypertension on heart and skeletal muscle glucose utilization. Results also were compared with those for 8 asymptomatic healthy control participants. RESULTS: Skeletal muscle glucose utilization rate was comparable between hypertensive NIDDM patients (61.2 +/- 55.5 micromol x min(-1) x kg(-1)) and normotensive NIDDM patients (50.9 +/- 25.2 micromol x min(-1) x kg(-1)) but was significantly reduced in both groups compared with control subjects (94.2 +/- 57.3 micromol x min(-1) x kg(-1)), as was the GDR (25.2 +/- 11.3 and 24.0 +/- 7.5 micromol x min(-1) x kg(-1)), respectively, for patients compared with 38.5 +/- 11.5 micromol x min(-1) x kg(-1) for control participants). However, the myocardial glucose utilization (MGU) rate was significantly reduced in NIDDM patients without hypertension (389 +/- 185 micromol x min(-1) x kg(-1)) than in those with hypertension (616 +/- 86.4 micromol x min(-1) x kg(-1), p < 0.01). Multivariate stepwise regression analysis has shown that MGU was significantly correlated with systolic blood pressure and plasma free fatty acid concentration. CONCLUSION: Whole-body insulin resistance was observed in NIDDM patients independent of hypertension. The MGU rate may have different properties to oppose insulin resistance than glucose utilization of skeletal muscle in hypertensive patients with NIDDM.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Angiopatías Diabéticas/metabolismo , Glucosa/metabolismo , Hipertensión/metabolismo , Resistencia a la Insulina , Músculo Esquelético/metabolismo , Miocardio/metabolismo , Tomografía Computarizada de Emisión , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Angiopatías Diabéticas/diagnóstico por imagen , Ácidos Grasos no Esterificados/sangre , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Técnica de Clampeo de la Glucosa , Corazón/diagnóstico por imagen , Humanos , Hipertensión/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Músculo Esquelético/diagnóstico por imagen , Radiofármacos
18.
J Nucl Med ; 42(7): 1005-10, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11438619

RESUMEN

UNLABELLED: Recently, troglitazone has emerged as an insulin sensitizer for the treatment of type II diabetes. However, its effect on skeletal muscle glucose use (SMGU) has not been studied. METHODS: To investigate the effect of troglitazone on SMGU in patients with type II diabetes, we undertook skeletal muscle (18)F-FDG PET dynamic imaging under insulin clamping before and after administration of SMGU to 20 patients with type II diabetes. Data were compared with those for 12 age-matched healthy volunteers. RESULTS: The whole-body glucose disposal rate (GDR) was significantly lower in patients (29.9 +/- 9.83 micromol/min/kg) than in control subjects (55.6 +/- 16.5 micromol/min/kg, P < 0.01), as was the SMGU (patients, 3.27 +/- 2.17 micromol/min/kg; control subjects, 10.9 +/- 6.4 micromol/min/kg; P < 0.01). After the therapy, GDR significantly improved in patients (29.3 +/- 14.6 micromol/min/kg, P < 0.05), as did SMGU (5.06 +/- 2.11 micromol/min/kg, P < 0.05). When results for patients with and without hypertension were separately analyzed, a significant improvement in SMGU after troglitazone was seen in both normotensive and hypertensive patients (normotensive [n = 10]: baseline, 3.67 +/- 2.89 micromol/min/kg; after therapy, 5.28 +/- 2.61 micromol/min/kg; P < 0.05; hypertensive [n = 10]: baseline, 2.89 +/- 1.22 micromol/min/kg; after therapy, 4.72 +/- 1.39 micromol/min/kg; P < 0.05). GDR in patients with and without hypertension was significantly improved by troglitazone (normotensive: baseline, 17.9 +/- 10.2 micromol/min/kg; after therapy, 31.9 +/- 15.9 micromol/min/kg; P < 0.01; hypertensive: baseline, 39.6 +/- 15.1 micromol/min/kg; after therapy, 47.7 +/- 23.8 micromol/min/kg; P < 0.05). The plasma free fatty acid concentration during insulin clamping was not changed by troglitazone (baseline, 1.1 +/- 0.86 mEq/L; after therapy, 0.93 +/- 0.65 mEq/L; P = not significant). CONCLUSION: Troglitazone can improve whole-body insulin resistance through the improvement of SMGU but not through a decline in plasma free fatty acid concentration in patients with type II diabetes with or without hypertension.


Asunto(s)
Cromanos/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Fluorodesoxiglucosa F18 , Glucosa/metabolismo , Hipoglucemiantes/uso terapéutico , Resistencia a la Insulina , Músculo Esquelético/metabolismo , Radiofármacos , Tiazoles/uso terapéutico , Tiazolidinedionas , Tomografía Computarizada de Emisión , Glucemia/análisis , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos no Esterificados/sangre , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/metabolismo , Insulina/sangre , Masculino , Persona de Mediana Edad , Músculo Esquelético/diagnóstico por imagen , Troglitazona
19.
J Nucl Med ; 41(6): 978-85, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10855621

RESUMEN

UNLABELLED: Coronary microangiopathy is a major complication in diabetics. However, the presence of independent factors in association with coronary microangiopathy in patients with non-insulin-dependent diabetes mellitus (NIDDM) or the difference in coronary microangiopathy between diabetics with coronary artery disease (CAD) and those with microvascular angina is unclear. METHODS: Nineteen patients with NIDDM and microvascular angina, 18 patients with NIDDM and CAD, and 17 age-matched control subjects were studied. Myocardial segments that were perfused by angiographically normal coronary arteries were studied. The baseline myocardial blood flow (MBF) and the MBF during dipyridamole administration were measured using PET and 13N-ammonia, after which the myocardial flow reserve (MFR) was calculated to assess coronary microangiopathy. RESULTS: The baseline MBF was comparable among NIDDM patients with microvascular angina, NIDDM patients with CAD, and control subjects. However, the MBF during dipyridamole administration was significantly lower in NIDDM patients with microvascular angina (126 +/- 42.7 mL/min/100 g) than that in either NIDDM patients with CAD (210 +/- 70.1 mL/min/100 g; P < 0.01) or control subjects (293 +/- 159 mL/min/100 g; P < 0.01), as was the MFR (NIDDM with microvascular angina, 1.90 +/- 0.73; NIDDM with CAD, 2.59 +/- 0.81 [P < 0.01]; control subjects, 3.69 +/- 1.09 [P < 0.01]). Multivariate stepwise regression analysis showed that, among the factors considered, glycemic control was independently related to the MFR (r = 0.838; P < 0.05). CONCLUSION: Glycemic control appears to be essential for coronary microangiopathy in NIDDM.


Asunto(s)
Glucemia/análisis , Enfermedad Coronaria/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/sangre , Angina Microvascular/complicaciones , Adulto , Anciano , Angiografía Coronaria , Circulación Coronaria , Enfermedad Coronaria/sangre , Enfermedad Coronaria/diagnóstico por imagen , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Dipiridamol , Electrocardiografía , Femenino , Hemodinámica , Humanos , Hipertensión/complicaciones , Resistencia a la Insulina , Masculino , Microcirculación , Angina Microvascular/sangre , Angina Microvascular/diagnóstico por imagen , Angina Microvascular/fisiopatología , Persona de Mediana Edad , Factores Sexuales , Tomografía Computarizada de Emisión
20.
J Nucl Med ; 40(7): 1116-21, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10405129

RESUMEN

UNLABELLED: Abnormal heart and skeletal muscle 18F-fluorodeoxyglucose (FDG) uptake in patients with insulin resistance has been demonstrated. Although the existence of whole-body insulin resistance has been reported in hypertriglyceridemics, its specific role in heart and skeletal muscle FDG uptake in hypertriglyceridemics has not been clarified. METHODS: We compared heart and skeletal muscle FDG uptake using PET and the whole-body glucose disposal rate (GDR) during insulin clamping in 17 hypertriglyceridemics and 12 age-matched control subjects to increase our knowledge of whole-body insulin resistance and its relationship to heart and skeletal muscle FDG uptake in hypertriglyceridemics. RESULTS: GDR was significantly reduced in hypertriglyceridemics compared with control subjects (4.50 +/- 1.37 mg/min/kg versus 10.0 +/- 2.97 mg/min/kg, P = 0.00001), as were the skeletal muscle FDG Ki = (k1 x k3)/(k2 + k3) (SFKi: 0.007 +/- 0.003 mL/min/g versus 0.018 +/- 0.01 mL/min/g, P = 0.0001) and skeletal muscle FDG uptake ([SMFU] 0.725 +/- 0.282 mg/min/100 g versus 1.86 +/- 1.06 mg/min/100 g, P = 0.00023). However, myocardial FDG Ki (MFKi) tended to be reduced in hypertriglyceridemics compared with that in control subjects (0.062 +/- 0.017 mL/min/g versus 0.068 +/- 0.015 mL/min/g), but the difference was statistically insignificant (P = 0.3532). Moreover, myocardial FDG uptake (MFU) in hypertriglyceridemics (6.47 +/- 1.72 mg/min/100 g) tended to be reduced compared with that in control subjects (6.97 +/- 1.73 mg/min/100 g), but the difference was statistically insignificant (P = 0.4485). GDR was significantly correlated with SFKi (r = 0.69, P = 0.0022), SMFU (r = 0.612, P = 0.009), MFKi (r = 0.57, P = 0.0174) and MFU (r = 0.505, P = 0.0385) in hypertriglyceridemics. CONCLUSION: Both heart and skeletal muscle glucose utilization were related to insulin resistance in hypertriglyceridemics. However, the less severe reduction in MFU (compared with SMFU) suggests that myocardium may have a mechanism to oppose insulin resistance in hypertriglyceridemics.


Asunto(s)
Corazón/diagnóstico por imagen , Hipertrigliceridemia/diagnóstico por imagen , Resistencia a la Insulina , Insulina/fisiología , Músculo Esquelético/diagnóstico por imagen , Tomografía Computarizada de Emisión , Estudios de Casos y Controles , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Glucosa/metabolismo , Técnica de Clampeo de la Glucosa , Humanos , Hipertrigliceridemia/metabolismo , Masculino , Persona de Mediana Edad , Radiofármacos
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