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1.
J Oral Rehabil ; 44(12): 948-956, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28853166

RESUMEN

A knowledge gap regarding masticatory performance in preschool children exists, which in turn delays intervention for preventive care; therefore, a method to easily assess performance is needed. The purpose of this study is to investigate the feasibility of assessing masticatory performance using colour-changeable chewing gum and to investigate masticatory performance-related factors in preschool children. This cross-sectional survey was conducted in two childcare facilities and our laboratory. First, a one-third quantity of colour-changeable chewing gum was masticated by six adults to assess the nature and progression of colour changes in this quantity. Then, masticatory performance in 370 children 4-6 years of age was assessed using the same quantity of colour-changeable chewing gum (60 chew strokes). The maximum bite force, body height, weight, age and number of healthy teeth were recorded. A t-test was performed to determine whether gum-chewing experience or lack thereof produced a significant difference in masticatory performance. The Spearman's rank correlation coefficient was then determined for masticatory performance assessment values and other factors solely for children with gum-chewing experience. Measurements from 259 children were obtained. Children with gum-chewing experience demons trated significantly higher assessment values and were deemed to have been correctly assessed. A very weak but significant positive correlation was observed only between masticatory performance and the number of healthy teeth. The masticatory performance of preschool children was easily assessed using colour-changeable chewing gum. The assessment values demonstrated significant correlation with the number of healthy teeth, but not with maximum bite force, body height, weight or age.


Asunto(s)
Goma de Mascar , Color , Masticación/fisiología , Destreza Motora/fisiología , Fuerza de la Mordida , Preescolar , Estudios Transversales , Dentición , Conducta Alimentaria , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
2.
Kyobu Geka ; 64(7): 570-3, 2011 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-21766710

RESUMEN

We report a rare case of metastatic brain and lymph node carcinoma of unknown primary origin. A 68-year-old man had been followed up after resection of brain metastasis in right parietooccipital region without suspicious primary site. Seventy-eight months after the resection, a mediastinal lymph node (#2R) of 15 mm in diameter was detected by computed tomography (CT) and was surgically removed. The histological diagnosis was poorly differentiated adenocarcinoma resembling lymphoepithelial carcinoma, which was similar to the histology of the previously resected brain tumor. This patient is alive without recurrence and apparent primary site at 24 months after lymph node resection.


Asunto(s)
Adenocarcinoma/patología , Adenocarcinoma/cirugía , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Metástasis Linfática , Mediastino , Neoplasias Primarias Desconocidas , Anciano , Estudios de Seguimiento , Humanos , Masculino
3.
Science ; 179(4073): 564-5, 1973 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-17820817

RESUMEN

Strengite (FePO(4) . 2H(2)O) undergoes partial dissolution under the reducing conditions existing in a flooded soil. The greatest release of phosphate and iron occurs under conditions of low oxidation-reduction potential in combination with low pH.

4.
Science ; 285(5432): 1408-11, 1999 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-10464101

RESUMEN

DFN3, an X chromosome-linked nonsyndromic mixed deafness, is caused by mutations in the BRN-4 gene, which encodes a POU transcription factor. Brn-4-deficient mice were created and found to exhibit profound deafness. No gross morphological changes were observed in the conductive ossicles or cochlea, although there was a dramatic reduction in endocochlear potential. Electron microscopy revealed severe ultrastructural alterations in cochlear spiral ligament fibrocytes. The findings suggest that these fibrocytes, which are mesenchymal in origin and for which a role in potassium ion homeostasis has been postulated, may play a critical role in auditory function.


Asunto(s)
Conducto Coclear/metabolismo , Proteínas de Unión al ADN , Sordera/metabolismo , Proteínas del Tejido Nervioso , Potasio/metabolismo , Factores de Transcripción/metabolismo , Animales , Conducto Coclear/patología , Sordera/genética , Sordera/patología , Oído Interno/metabolismo , Oído Interno/patología , Oído Medio/patología , Endolinfa/metabolismo , Potenciales Evocados Auditivos del Tronco Encefálico , Femenino , Expresión Génica , Marcación de Gen , Ligamiento Genético , Hibridación in Situ , Transporte Iónico , Masculino , Potenciales de la Membrana , Ratones , Ratones Endogámicos C57BL , Mutagénesis , Factores del Dominio POU , Factores de Transcripción/genética , Cromosoma X
5.
Eur Respir J ; 31(6): 1268-73, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18287124

RESUMEN

Adrenal insufficiency is believed to occur frequently in severe sepsis and septic shock. The aim of the present study was to determine whether adrenal function is also related to the severity of community-acquired pneumonia (CAP). In total, 64 Japanese patients with CAP were consecutively enrolled in the present study, which was carried out during 2005-2006. Serum adrenocorticotropic hormone (ACTH) and cortisol were measured in each subject, as was the response of cortisol secretion when 250 mug of cosyntropin was administered. Analyses were performed comparing these values with the score calculated according to the Pneumonia Patient Outcomes Research Team (PORT) cohort study, the number of in-hospital deaths and the length of hospital stay. As the PORT score increased, serum ACTH and cortisol also increased, while the response of cortisol secretion to the administration of cosyntropin decreased. In the analysis by receiver operating characteristic curves, adrenal dysfunction was related significantly to both the number of in-hospital deaths and the length of hospital stay. Adrenal dysfunction was shown to correlate with the Pneumonia Patient Outcomes Research Team score and the clinical outcomes, while adrenal insufficiency defined by the cosyntropin stimulation test was rare in the present study.


Asunto(s)
Hidrocortisona , Sistema Hipotálamo-Hipofisario/fisiopatología , Sistema Hipófiso-Suprarrenal/fisiopatología , Neumonía Bacteriana/fisiopatología , Corticoesteroides/uso terapéutico , Hormona Adrenocorticotrópica/sangre , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Infecciones Comunitarias Adquiridas/fisiopatología , Femenino , Humanos , Hidrocortisona/sangre , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/inmunología , Curva ROC , Índice de Severidad de la Enfermedad , Análisis de Supervivencia
6.
Biochim Biophys Acta ; 1445(1): 123-33, 1999 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-10209264

RESUMEN

Induction of the heat shock proteins (HSPs) is involved in the increased resistance to cancer therapies such as chemotherapy and hyperthermia. We used two human ovarian cancer cell lines; a cisplatin (CDDP)-sensitive line A2780 and its CDDP-resistant derivative, A2780CP. The concentration of intracellular glutathione (GSH) is higher (2.7-fold increase) in A2780CP cells than in A2780 cells. A mild treatment with a heat stress (42 degrees C for 30 min) induced synthesis of both the heat shock protein 72 (Hsp72) mRNA and the HSP72 protein in A2780CP cells, but not in A2780 cells. In contrast, a severe heat stress (45 degrees C for 30 min) increased synthesis of the HSP72 protein in the two cell lines. The induced level of the HSP72 protein by the severe treatment was higher in A2780CP than in A2780 cells. The gel mobility shift assay showed that DNA binding activities of the heat shock factor (HSF) in the two cell lines were induced similarly and significantly by the mild heat stress. Immunocytochemistry using an anti HSF1 antibody also indicated that mild heat stress activated the HSF1 translocation from the cytosol to the nucleus similarly in the both cell lines. Pretreatment of CDDP-sensitive A2780 cells with N-acetyl-L-cysteine, a precursor of GSH, effectively enhanced induction of the Hsp72 mRNA by the mild heat stress. The present findings demonstrate that induction of the Hsp72 mRNA by the mild heat stress was more extensive in CDDP-resistant A2780CP cells. It is likely that the higher GSH concentration in A2780CP cells plays an important role in promoting Hsp72 gene expression induced by the mild heat stress probably through processes downstream of activation of HSF-DNA binding.


Asunto(s)
Cisplatino/farmacología , Proteínas de Choque Térmico/biosíntesis , Calor , Resistencia a Medicamentos , Regulación de la Expresión Génica , Glutatión/metabolismo , Proteínas del Choque Térmico HSP72 , Proteínas de Choque Térmico/genética , Humanos , ARN Mensajero/biosíntesis , Células Tumorales Cultivadas
7.
Biochim Biophys Acta ; 1380(1): 123-32, 1998 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-9545559

RESUMEN

Cadmium induces the expression of the 70 kDa heat shock protein (HSP70) and metallothionein (MT), both of which are considered to be associated with intracellular glutathione (GSH) metabolism in the cellular protection mechanism against cadmium-induced cellular injury. We determined the effects of N-acetyl-L-cysteine (NAC), which increases the intracellular GSH levels, on the induction of HSP70 and MT gene expression in a cultured cell line of human amniotic cells (WISH) exposed to CdCl2. The mRNA level of MT-II, a major isoform of MT genes, was more prominently increased than that of HSP70 when WISH cells were exposed to CdCl2 (5-15 microM, for 6 h). The treatment of WISH cells with 1.5 and 30 mM NAC for 2 h increased the intracellular GSH levels by 1.4- and 3.1-fold, respectively. Pretreatment of cells with 30 mM NAC significantly reduced both HSP70 and MT-II mRNA levels in the cells exposed to 50 microM CdCl2. This concentration of NAC also efficiently suppressed the cadmium-induced lethality. On the contrary, pretreatment with 1.5 mM NAC suppressed only the induction of HSP70 gene expression in the 50 microM CdCl2-treated cells, and did not inhibit the metal toxicity. However, this low concentration of NAC efficiently suppressed lipid peroxidation which was increased by 50 microM CdCl2. Furthermore, this low concentration of NAC also decreased the CdCl2-induced gene expression of HSP32 which represents a general response to oxidative stress. Taken together, NAC seems to have at least two concentration-dependent functions in WISH cells exposed to CdCl2; the low concentration of NAC can suppress the induction of HSP70 gene expression as well as the increase of lipid peroxidation via an antioxidant pathway, while the high concentration of NAC can suppress the induction of MT-II mRNA as well as cadmium-induced cell death. Our present data suggest that changes in intracellular redox status, as reflected by GSH concentration, have more important effects on the induction of HSP70 mRNA rather than that of MT-II mRNA in human amniotic cells exposed to cadmium.


Asunto(s)
Acetilcisteína/farmacología , Cadmio/toxicidad , Proteínas HSP70 de Choque Térmico/genética , Metalotioneína/genética , Acetilcisteína/administración & dosificación , Amnios , Línea Celular , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Glutatión/metabolismo , Humanos , Peroxidación de Lípido/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo
8.
Biochim Biophys Acta ; 910(2): 171-81, 1987 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-2823899

RESUMEN

We have determined the nucleotide sequence of the cell binding domain region of the chicken fibronectin gene and analyzed it evolutionaly. We present here the complete nucleotide sequence of 4.3 kb HindIII/EcoRI segment from the clone lambda FC23 of the chicken fibronectin gene. There were five exons in this segment. When we lined up the amino acid of exons 28, 29 and 31, three alignments, known as the Type III repeat, appeared. Tetrapeptide, -RGDS-, called the cell binding domain, existed in the second repeat, coding exon 30. It was presumed that the Type III repeats were composed of two exons in the chicken gene, the same as in the rat and humans. We found repeatedly appearing amino-acid sequences such as -TIT- (three arrays in these Type III repeats) but also found one of the amino acids substituted in the tripeptide in these Type III repeats (seven arrays). We analyzed these repeats from the point of view of evolution. We used three of the nucleotide sequences (12-18 bp) coding such -TIT- repeats as a unit length for comparing the various homologies after dividing the coding region into 56 segments. The mutual homology of the divided segments to each one of three showed 53% on average. On the other hand, the mutual nucleotide homology of the Type III repeat was 44%. This suggested that the Type III repeat may have been developed by frequent duplication of small gene units.


Asunto(s)
Fibronectinas/genética , Genes , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Evolución Biológica , Pollos , Clonación Molecular , ADN/genética , ADN/metabolismo , ADN/ultraestructura , Enzimas de Restricción del ADN , Amplificación de Genes , Intrones , Datos de Secuencia Molecular
9.
Biomed Pharmacother ; 59 Suppl 1: S188-91, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16275492

RESUMEN

BACKGROUND: The impaired balance of the low-frequency/high-frequency ratio obtained from spectral components of RR intervals can be a diagnostic test for sepsis. In addition, it is known that a reduction of heart rate variability (HRV) is useful in identifying septic patients at risk of the development of multiple organ dysfunction syndrome (MODS). We have reported a non-contact method using a microwave radar to monitor the heart and respiratory rates of a healthy person placed inside an isolator or of experimental animals exposed to toxic materials. APPARATUS DESIGN AND TESTING: With the purpose of preventing secondary exposure of medical personnel to toxic materials under biochemical hazard conditions, we designed a novel apparatus for non-contact measurement of HRV using a 1215 MHz microwave radar, a high-pass filter, and a personal computer. The microwave radar monitors only the small reflected waves from the subject's chest wall, which are modulated by the cardiac and respiratory motion. The high-pass filter enhances the cardiac signal and attenuates the respiratory signal. In a human trial, RR intervals derived from the non-contact apparatus significantly correlated with those derived from ECG (r=0.98, P<0.0001). The non-contact apparatus showed a similar power spectrum of RR intervals to that of ECG. CONCLUSIONS: Our non-contact HRV measurement apparatus appears promising for future pre-hospital monitoring of septic patients or for predicting MODS patients, inside isolators or in the field for mass casualties under biochemical hazard circumstances.


Asunto(s)
Sustancias Peligrosas , Frecuencia Cardíaca/fisiología , Monitoreo Fisiológico/instrumentación , Insuficiencia Multiorgánica/diagnóstico , Exposición Profesional/prevención & control , Radar , Sepsis/fisiopatología , Adulto , Electrocardiografía , Humanos , Masculino , Microcomputadores , Microondas , Aisladores de Pacientes , Personal de Hospital , Mecánica Respiratoria/fisiología , Medición de Riesgo , Tórax/fisiología
10.
J Leukoc Biol ; 46(2): 96-102, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2746139

RESUMEN

A monoclonal antibody (RP-3) that depletes rat neutrophils selectively in vivo was developed by hybridization of mouse myeloma cells (P3-X63.Ag8.653) and spleen cells of BALB/c mice sensitized with peritoneal neutrophils of WKA/Hok rats. RP-3 reacted with rat neutrophils but not with lymphocytes, macrophages, natural killer cells, basophils, eosinophils, or tissues of various organs. The mitogenic responsiveness to concanavalin A (ConA), phytohemagglutinin (PHA), and lipopolysaccharide (LPS) of rats given RP-3 was not significantly different from that of normal rats. Administration of RP-3 into the peritoneal cavity of rats that had been kept under specific pathogen-free (SPF) or clean conditions induced selective depletion of circulating neutrophils to under 100/mm3 (0.5% WBC). The numbers of monocytes, lymphocytes, and platelets were not changed. Administration of 2 ml of RP-3 reduced blood neutrophils to under 100/mm3 for approximately 24 h, and administration of 1 ml caused depletion for approximately 12 h.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Neutrófilos/citología , Animales , Especificidad de Anticuerpos , Supervivencia Celular/efectos de los fármacos , Inyecciones Intraperitoneales , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Ratas , Ratas Endogámicas
11.
J Clin Endocrinol Metab ; 52(5): 1023-6, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-6908897

RESUMEN

The effect of aging on urinary kallikrein excretion (UkalV) was investigated in 54 normal subjects, 11-88 yr old, and 37 patients with essential hypertension, 17-82 yr old. Urinary sodium, potassium, and aldosterone excretion (U(Ald)V) were also measured in these subjects. Urinary sodium and potassium excretion in both normal subjects and hypertensive patients did not significantly change with aging. In normal subjects, U(kal)V (r = 0.45; P less than 0.001) and U(Ald)V (r = 0.58; P less than 0.01) significantly decreased with increasing age. U(kal)V was positively correlated with U(Ald)V (r = 0.44; P less than 0.001). In contrast, the hypertensive patients had a significant decrease with age in U(Ald)V (r = -0.36; P less than 0.05), but no significant age-related change in U(kal)V. No significant correlation between U(kal)V and U(Ald)V was observed in the hypertensive patients. In individuals less than 60 yr old, there was no significant difference in U(kal)V values between normal subjects and hypertensive patients. Hypertensive patients more than 60 yr old excreted more urinary kallikrein than normal subjects of the same age group (P less than 0.05). In conclusion, the age-related decrease of U(kal)V in normal subjects may be due to the reduced activity of the renin-angiotensin-aldosterone system. It remains to be elucidated whether the absence of the age-related decrease in U(kal)V in hypertensive patients is related to the pathogenesis or pathophysiology of essential hypertension.


Asunto(s)
Envejecimiento , Hipertensión/orina , Calicreínas/orina , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
J Clin Endocrinol Metab ; 54(4): 682-8, 1982 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7037811

RESUMEN

Little is known about changes in inactive plasma renin in various conditions or the in vivo activation mechanism of inactive renin. The effects of various factors known to stimulate or suppress renin release on active and inactive PRA were examined in normal subjects. Inactive PRA was determined as the difference between the total PRA after trypsin activation and active PRA. Concurrent measurements of urinary kallikrein excretion and plasma prekallikrein activity were performed to assess the possible role of renal or plasma kallikrein in in vivo activation of inactive renin. Short term stimulation with iv furosemide and ambulation, infusion of isoproterenol, and administration of captopril increased active PRA, but had little or no effect on inactive PRA. Sodium restriction and sodium loading, each for 4 days, induced parallel changes in active and inactive PRA. The administration of propranolol for 4 days decreased active PRA but did not change inactive PRA. There were no significant correlations between the changes in urinary kallikrein excretion and those in active PRA or in the proportion of active to total PRA after any short term treatments, except furosemide administration. Plasma prekallikrein activity was correlated with the proportion of active renin only during the long term sodium balance study. The present data suggest that the mechanisms ofr the control of inactive and active renin are different. Neither renal nor plasma kallikrein seems to be consistently involved in the in vivo activation of inactive renin.


Asunto(s)
Calicreínas/análisis , Calicreínas/orina , Precalicreína/análisis , Renina/sangre , Adulto , Captopril , Furosemida , Humanos , Isoproterenol , Locomoción , Masculino , Propranolol , Valores de Referencia , Sodio/metabolismo
13.
Mech Ageing Dev ; 52(1): 93-106, 1990 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2314131

RESUMEN

Accumulation of lipofuscin is an important phenomenon of the cellular aging process. The first appearance of cardiac lipofuscin showed a good correlation with sexual maturation, which was correlated with maximum life-span of mammals. Large metabolic changes occurred at sexual maturation. From these results, it is suggested that sexual maturation of mammals is the initiation period of the aging process. Correlation between sexual maturation and longevity was re-evaluated using many mammals. Domestic and laboratory animals showed an earlier sexual maturation than other mammals, including rodents.


Asunto(s)
Envejecimiento/fisiología , Corazón/fisiología , Lipofuscina/fisiología , Pigmentos Biológicos/fisiología , Maduración Sexual/fisiología , Animales , Supervivencia Celular/fisiología , Femenino , Técnicas In Vitro , Macaca , Macaca mulatta , Masculino , Miocardio/citología , Conejos , Factores de Tiempo
14.
Mech Ageing Dev ; 66(3): 243-8, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8469016

RESUMEN

Previously, we have reported that the aging process begins at sexual maturation (Nakano, M. et al., Mech. Ageing Dev., 52 (1990) 93-106). In this paper, we reported the cardiac lipofuscin accumulation of crab-eating monkeys. The first appearance of cardiac lipofuscin was around sexual maturation, and the rate of accumulation in crab-eating monkey was 0.45. Several primates which have different life spans show the same rate of lipofuscin accumulation in the life stage. Namely, even in a different life span, the amount of lipofuscin accumulation in a given period of life such as puberty, middle age, old age was the same. From these results, it is suggested that the amount of lipofuscin accumulation is the same in the life span of primates having different life spans.


Asunto(s)
Envejecimiento/metabolismo , Lipofuscina/metabolismo , Macaca fascicularis/metabolismo , Animales , Femenino , Humanos , Longevidad , Masculino , Miocardio/metabolismo , Primates/metabolismo , Maduración Sexual , Especificidad de la Especie
15.
Mech Ageing Dev ; 49(1): 41-8, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2747299

RESUMEN

Deposition of lipofuscin autofluorescent granules, is an important phenomenon in the aging process. Cardiac lipofuscin in Japanese monkey (Macaca fuscata) first appears at approximately two years of age. Thereafter, the amount of cardiac lipofuscin increases with increasing age. The first appearance of cardiac lipofuscin shows a good correlation with the maximum life span of animals. Moreover, the rate of lipofuscin accumulation is inversely correlated with life span energy potential (LEP) of animals. From these results, it is suggested that the rate of lipofuscin accumulation depends on the total life span energy expenditure of the tissue.


Asunto(s)
Envejecimiento/metabolismo , Lipofuscina/farmacocinética , Miocardio/metabolismo , Pigmentos Biológicos/farmacocinética , Animales , Femenino , Longevidad , Macaca , Masculino
16.
Biochimie ; 75(6): 459-65, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8364096

RESUMEN

We superimposed hydropathic indexes of the human fibronectin cell binding domain (CBD) on the lambda phage J protein by computer, and substituted 22 amino acids from the fibronectin CBD for a part of the lambda phage J protein. The fibronectin cell binding domain -Arg-Gly-Asp-Ser- (-RGDS-) localizes at the junction of hydrophobicity and hydrophilicity. We selected a similar hydrophobic-to-hydrophilic junction in the J protein region for substitution. This junction corresponds to 150 bp of the PstI fragment of J protein cDNA. We synthesized 150 bp of the relevant PstI fragment that includes the cell binding domain region. The region was then constructed by serial cloning as an expression vector, pJCBD. The vector pJCBD expressed the fused protein named JCBD (M(r) 32 kDa) in E coli XL1-BLUE. The expressed JCBD protein was identified by Western blot analysis in the extract of the pJCBD carrying bacterial lysate using both rabbit anti-lambda phage antiserum and anti-CBD of fibronectin antibody. The JCBD protein appeared to recognize retinoblast cell membrane RGDS-directed receptors, detected by enzyme-linked immuno-sorbent assay and also by binding competition assay with synthetic pentapeptides, Gly-Arg-Gly-Asp-Ser (GRGDS) and Gly-Arg-Gly-Glu-Ser (GRGES). The former competitor inhibited completely fibronectin CBD-dependent binding activity of JCBD, the latter had no inhibitory activity. These results suggest that certain functional proteins engineered by computer design between human fibronectin cell binding domain and lambda phage J protein can be produced.


Asunto(s)
Células/metabolismo , Simulación por Computador , Fibronectinas/química , Ingeniería de Proteínas , Proteínas de la Cola de los Virus/química , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Fibronectinas/genética , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/química , Proteínas de la Cola de los Virus/genética
17.
Thromb Haemost ; 73(5): 812-8, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7482408

RESUMEN

To investigate the effects of transforming growth factor-betas (TGF-betas) on endothelial anticoagulant activity, we assayed thrombomodulin (TM) activity and antigen levels of human umbilical vein endothelial cells (HUVECs) incubated with TGF-betas in vitro. TGF-beta 1 suppressed surface TM activity and surface TM antigen levels maximally 12 h after incubation in dose-dependent manners. TGF-beta 2 was almost equipotent with TGF-beta 1 for the suppression of them. Both TGF-betas suppressed total TM antigen level in HUVECs, and the time course of the suppression was similar to that of the cell surface TM antigen level. The maximal reductions of TM mRNA levels by TGF-betas were observed at several hours ahead of those observed in both surface and total TM antigens levels, suggesting that the TGF-beta-mediated suppression of TM antigen of HUVECs is primarily regulated at the TM mRNA level. Our present work suggests that the down-modulation of TM level induced by TGF-betas in HUVECs contributes in vivo to promoting the thrombogenesis either at the sites of injury of vessel walls, such as atherosclerotic lesions where TGF-beta 1 is released from platelets, smooth muscle cells and monocytes, or at neovascular walls in tumors secreting TGF-beta 2.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Trombomodulina/biosíntesis , Factor de Crecimiento Transformador beta/farmacología , Células Cultivadas , Depresión Química , Relación Dosis-Respuesta a Droga , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Trombomodulina/genética , Venas Umbilicales
18.
Immunol Lett ; 9(2-3): 153-9, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2985496

RESUMEN

A novel factor was found in the medium conditioned by SV40-transformed human embryo fibroblasts, which stimulate concanavalin A-induced thymocyte DNA synthetic response. This activity was estimated to be 10-15 kD and divided into two activities by ion exchange chromatography. One of them is a protein molecule and the other is a glycoprotein. In addition, these activities are not derived from the growth factors reported previously such as interleukin 2 (Morgan, R., Ruscetti, F. and Gallo, R. C. (1976) Science 193, 1007-1008) and transforming growth factor (De Larco, J. E. and Todaro, G. J. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 4001-4005).


Asunto(s)
Transformación Celular Viral , Interleucina-1/aislamiento & purificación , Activación de Linfocitos , Linfocitos T/inmunología , Animales , Células Cultivadas , Concanavalina A/farmacología , Embrión de Mamíferos , Fibroblastos , Humanos , Técnicas In Vitro , Ratones , Virus 40 de los Simios
19.
Cancer Lett ; 140(1-2): 59-67, 1999 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10403542

RESUMEN

The post-initiation stage of hepatocarcinogenesis was investigated in carcinogen-resistant inbred DRH rats and the parental strain, carcinogen-sensitive Donryu rats. Male rats at 5 weeks of age from both strains were treated with N-nitrosodiethylamine (200 mg/kg i.p.) followed by feeding with a diet containing 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) from 2 weeks later and were then subjected to partial hepatectomy at 1 week later. At 8 weeks after the start of treatment, the mean area occupied by glutathione S-transferase placental form (GST-P)-positive lesions was about 30% in Donryu rats but less than 4% in DRH rats despite the presence of comparable numbers of foci in the livers of both strains. These observations suggested that clonal expansion of GST-P-positive foci in DRH rat liver was significantly suppressed under these conditions. Furthermore, this genetic property was dominantly inherited in the F1 rats by crosses of DRH and carcinogen-sensitive inbred F344 rats; that is, the induction of GST-P mRNA in the livers of F344 x DRH F1 rats was dominantly suppressed after administration of 3'-Me-DAB for 8 weeks as compared with parental F344 rats under the same conditions. We compared the intrinsic properties related to growth potential of liver cells between adult DRH and Donryu rats. DRH rat liver showed retarded and/or reduced DNA synthesis after partial hepatectomy or a single i.v. injection of lead nitrate and lower activity of telomerase induced by 3'-Me-DAB administration for 1 week, as compared with the Donryu rat liver. The intrinsic properties observed in this study may be related, at least in part, to the low incidence of liver tumors induced by hepatocarcinogens in DRH rats.


Asunto(s)
Glutatión Transferasa/metabolismo , Neoplasias Hepáticas Experimentales/enzimología , Neoplasias Hepáticas Experimentales/genética , Lesiones Precancerosas/enzimología , Animales , Northern Blotting , Peso Corporal/efectos de los fármacos , División Celular/efectos de los fármacos , División Celular/genética , Cruzamientos Genéticos , ADN/biosíntesis , Dietilnitrosamina , Glutatión Transferasa/genética , Hepatectomía , Plomo/farmacología , Neoplasias Hepáticas Experimentales/inducido químicamente , Masculino , Metildimetilaminoazobenceno , Nitratos/farmacología , Tamaño de los Órganos/efectos de los fármacos , Lesiones Precancerosas/inducido químicamente , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas , Telomerasa/metabolismo
20.
Radiother Oncol ; 41(3): 221-4, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9027937

RESUMEN

The dosimetric characteristics of linear accelerator radiosurgery for 10-MV X-ray were measured. Measurement of the relative output factor and tissue maximum ratio with a microchamber produced results equivalent to those of measurement with X-ray film. The 80% isodose level width measured with the microchamber was significantly smaller than that measured with the X-ray film. For the measurement of relative output factor and tissue maximum ratio, a microchamber seems to be the more appropriate choice. X-Ray film was found to be suitable for beam profile measurement.


Asunto(s)
Dosis de Radiación , Radiocirugia , Radioterapia de Alta Energía , Fantasmas de Imagen , Radiocirugia/instrumentación , Dosificación Radioterapéutica
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