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1.
Radiography (Lond) ; 27(1): 136-141, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32727709

RESUMEN

INTRODUCTION: The protocol for preparation of computed tomography urography (CTU) examinations at our hospital was changed in 2013 to improve the quality of urinary bladder filling in the excretory phase. The aim of this study was to evaluate the quality of urinary bladder filling on CTU after different doses of furosemide were administered to patients with macroscopic hematuria. METHODS: The cohort was 215 patients who underwent elective CTU due to macroscopic hematuria between 2014 and 2018. 5 mg furosemide were administrated to 100 patients, 2.5 mg to 100 patients and 0 mg to 15 patients. Contrast medium layered bladders were excluded, leaving 193 patients: 92, 89 and 12 in each group. Urinary bladder volume was calculated in corticomedullary (CMP) and excretory phase (EP). Bladder distension was classified as satisfactory or not. Attenuation of bladder content in EP was noted. RESULTS: Average volume in EP was 370 ± 224 ml (28-1052) after 5 mg furosemide, 274 ± 120 ml (43-628) after 2.5 mg and 180 ± 104 ml (53-351) after 0 mg. 85% of the bladders were satisfactory distended after 5 mg, 80% after 2.5 mg and 58% after 0 mg. Average attenuation was 266 ± 89 HU (103-524) after 5 mg, 362 ± 156 HU (118-948) after 2.5 mg and 761 ± 331 HU (347-1206) after 0 mg. The differences in volume and attenuation were significant. CONCLUSION: 5 mg furosemide is preferred rather than 2.5 mg in preparation for CTU examinations of patients with macroscopic hematuria. There was no difference between the doses concerning rate of satisfactory bladder distension, but the higher dose resulted in larger bladder volume and more suitable attenuation of bladder content. IMPLICATIONS FOR PRACTICE: Development of CTU-image quality could improve bladder cancer diagnostics.


Asunto(s)
Furosemida , Vejiga Urinaria , Hematuria/diagnóstico por imagen , Humanos , Tomografía Computarizada por Rayos X , Vejiga Urinaria/diagnóstico por imagen , Urografía
2.
J Intern Med ; 262(5): 537-44, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17908159

RESUMEN

OBJECTIVES: To investigate how life style factors such as alcohol consumption and physical activity relate to the serum apoB / apoA-I ratio in a cohort of middle-aged women with varying degrees of glucose tolerance. DESIGN: Observational, cross-sectional cohort study. SETTING: Research laboratory at a University Hospital. SUBJECTS: A screened cohort of 64-year-old postmenopausal women with varying degrees of glucose tolerance, ranging from diabetes (n = 232), impaired (n = 212) and normal (n = 191) glucose tolerance. MAIN OUTCOME MEASURE: ApoB / apoA-I ratio in relation to alcohol consumption and physical activity as assessed by questionnaires. RESULTS: Alcohol consumption and regular physical activity at high levels were inversely associated with the serum apoB / apoA-I ratio independently of confounding factors such as obesity, lipid-lowering treatment, degree of glucose tolerance and hormone replacement therapy. Alcohol seemed related to the apoB / apoA-I ratio mainly through increasing apoA-I, whereas physical activity seemed mainly related to lowering of apoB. Alcohol consumption above a daily intake of 8.9 g, i.e. less than a glass of wine was accompanied by a decrease in apoB / apoA-I ratio. CONCLUSIONS: Amongst these 64-year-old women with varying degrees of glucose tolerance, a moderate alcohol intake and regular physical exercise leading to sweating were associated with lower apoB / apoA-I ratio and these effects seem to be additive.


Asunto(s)
Apolipoproteínas/sangre , Diabetes Mellitus Tipo 2/sangre , Intolerancia a la Glucosa/sangre , Estilo de Vida , Consumo de Bebidas Alcohólicas/sangre , Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Estudios de Cohortes , Estudios Transversales , Escolaridad , Ejercicio Físico/fisiología , Femenino , Terapia de Reemplazo de Hormonas , Humanos , Persona de Mediana Edad
3.
Am J Transplant ; 6(2): 324-30, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16426316

RESUMEN

The occurrence of scoliosis in children after solid organ transplantation is not known. A total of 196 children, which is 93% of patients surviving kidney, liver and heart transplantation in our country, participated in a cross-sectional survey. All children were screened for rib hump, and those with clinically significant hump (over 6 degrees ) underwent radiographs of the spine. The occurrence of scoliosis was compared to data obtained from a previously published comparison group. Forty-three (21.9%) of the patients had scoliosis greater than 10 degrees , and 21 (10.7%) of them had curves greater than 20 degrees . The RR (95% CI) for scoliosis needing treatment (over 20 degrees ) was 17.0 (6.75-42.7) in the patients as compared with control population. The occurrence of scoliosis was 17.9% of the kidney, 13.6% of the liver and 51.7% of the heart transplant patients (p < 0.001). In a logistic regression model, heart transplantation (OR (95% CI) 7.27 (2.62-20.2)) and growth hormone treatment (3.98 (1.77-8.94)) were most significant risk factors for scoliosis. The risk of scoliosis is increased in patients with solid organ transplantation. Pediatricians treating these patients should be aware of this increased risk to diagnose early curves and to refer these patients to an orthopedic surgeon.


Asunto(s)
Densidad Ósea , Trasplante de Corazón/efectos adversos , Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Escoliosis/epidemiología , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Finlandia/epidemiología , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/epidemiología
4.
Eur Respir J ; 22(1): 113-7, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12882460

RESUMEN

There is little information of lower respiratory symptoms, bronchial hyperresponsiveness and airway inflammation in elite ice hockey players. A total of 88 highly trained ice hockey players and 47 control subjects were studied. All the subjects were subjected to skin-prick tests, resting spirometry examinations and histamine-challenge tests. Adequate induced sputum samples were obtained from 68 of the ice hockey players and from 18 symptom-free control subjects on a separate day. Bronchial hyperresponsiveness in a histamine-challenge test was found in 21 (24%) of the athletes and in five (11%) of the controls. Current asthma (current asthmatic symptoms and increased bronchial responsiveness) was observed in 13 (15%) of the athletes and in one (2%) of the control subjects. Total asthma (current asthma or previously physician-diagnosed asthma) occurred in 19 (22%) of the athletes and in two (4%) of the controls. Atopy, according to skin-prick tests, was observed in 51 (58%) of the athletes and 17 (36%) of the control subjects. The differential cell counts of eosinophils (2.6 versus 0.2%) and neutrophils (80.9 versus 29.9%) in the sputum samples of the ice hockey players were significantly higher than in those of the control subjects. Asthma is common in elite ice hockey players and they show signs of a mixed type of neutrophilic and eosinophilic airway inflammation. Inhalation of cold air associated with exposure to indoor pollutants during intensive training is a possible causative factor.


Asunto(s)
Asma/epidemiología , Hiperreactividad Bronquial/epidemiología , Hockey/estadística & datos numéricos , Adolescente , Adulto , Asma/etiología , Hiperreactividad Bronquial/etiología , Pruebas de Provocación Bronquial , Estudios de Casos y Controles , Femenino , Finlandia/epidemiología , Humanos , Incidencia , Inflamación/epidemiología , Masculino , Factores de Riesgo , Pruebas Cutáneas
5.
Int J Sports Med ; 23(4): 252-61, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12015625

RESUMEN

Exercise-induced changes in postexercise pulmonary function have not been studied in healthy elite athletes in normal training conditions. Twelve healthy elite runners volunteered. They showed normal resting spirometry and bronchial responsiveness to histamine, and were non-atopic. They performed free running exercise challenge tests (ECT) at subzero temperature and immediately after highest birch pollen season. The mean maximal postexercise changes in FEV(1), PEF, FVC, and FEV(1)/FVC did not differ between the cold air and pollen season ECTs. Compared with pre-exercise values, FEV(1)increased significantly at 10 min (p = 0.028) and 20 min (p = 0.033) postexercise in the cold air ECT, as well as at 10 min (p = 0.024) and 20 min (p = 0.010) postexercise in the pollen season ECT. The mean (SEM) maximal postexercise change in FEV(1) was mostly small + 2.6 (0.6)% in the winter and + 2.7 (0.9)% in the pollen season. In contrast, significant decreases in PEF, compared with baseline, were found at 10 min (p = 0.071) and 20 min (p = 0.0029) postexercise in the cold air ECT, as well as at 10 min (p = 0.060) and 20 min (p = 0.010) postexercise in the pollen season ECT (p = 0.0076). The mean (SEM) maximal postexercise fall in PEF was 5.9 (1.0)% in the winter and 6.0 (1.8)% in the pollen season. Heavy exercise challenge tests in extreme conditions increased FEV(1) post-exercise, while PEF decreased as compared with pre-exercise values. Thus, even small postexercise falls in FEV(1) may be considered as deviate exercise responses in elite athletes.


Asunto(s)
Frío , Ejercicio Físico/fisiología , Polen , Pruebas de Función Respiratoria , Carrera/fisiología , Adulto , Alérgenos , Betula , Pruebas de Provocación Bronquial , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Pruebas Cutáneas
6.
J Oral Pathol Med ; 30(9): 553-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11555159

RESUMEN

HIV infection reduces oral defensive mechanisms and may affect mucosal integrity. Differences in salivary protein concentrations and periodontopathogenic bacteria were studied in 56 HIV-infected patients with respect to their disease phase. Thirty-three patients were followed up for 2 years. Fifty-three healthy subjects of corresponding age and sex were studied as controls. At baseline, salivary albumin, total protein, IgA, and IgM levels were significantly higher (P<0.05-0.0001) in all phases of HIV infection, except the asymptomatic (ASX) phase, when compared with the control group. IgG levels were significantly increased in all phases except the ASX phase (P<0.05). After 2 years, salivary total protein, IgG, and IgM levels were still higher (P<0.05-0.005) in all HIV phases when compared with the control group (P<0.05-0.005). The albumin level was significantly higher in the ASX phase (P<0.005) and in the AIDS-related complex phase (ARC) (P<0.05), while the increase in IgA level was significant only in the ARC phase (P<0.005). Periodontopathogenic bacteria analyzed by PCR were detected both in the patients and the non-infected, but a statistically significant difference in the carriage percentage between the follow-up lymphadenopathy syndrome phase (LAS) and the control group was found only in Porphyromonas gingivalis (P<0.05) and Bacteroides forsythus (P< 0.0001). Thus, HIV infection appeared to cause a significant increase in the studied salivary proteins, suggesting leakage of serum components into the mouth.


Asunto(s)
Infecciones por VIH/metabolismo , Adulto , Anciano , Albúminas/aislamiento & purificación , Bacteroides/aislamiento & purificación , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Estudios de Seguimiento , Infecciones por VIH/sangre , Infecciones por VIH/microbiología , Humanos , Isotipos de Inmunoglobulinas/aislamiento & purificación , Masculino , Persona de Mediana Edad , Porphyromonas gingivalis/aislamiento & purificación , Saliva/inmunología , Saliva/metabolismo , Saliva/microbiología , Proteínas y Péptidos Salivales/aislamiento & purificación
7.
Cancer Res ; 61(14): 5340-4, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11454671

RESUMEN

Prostate cancer is the most common male malignancy in the United States as well as in many European countries. It is curable as long as it is localized, but the invasion of prostate cancer and formation of metastasis turn it into a life-threatening disease. Urokinase-type plasminogen activator (uPA) is believed to play a key role in tissue degradation and cell migration under various normal and pathological conditions, including cancer invasion and metastasis. Increased expression of uPA has been reported in various malignancies including prostate cancer. However, the mechanisms of the overexpression have remained poorly understood. Here, we report increased copy number of uPA gene in 3 of 13 hormone-refractory prostate carcinomas, including 1 high-level amplification. Real-time quantitative reverse transcription-PCR showed that the increased expression of uPA coincided with the amplification of the gene in these tumors. Matrigel invasion assay showed that prostate cancer cell line PC-3, containing amplification of the uPA gene, was more sensitive to the urokinase inhibitor, amiloride, than DU145 or LNCaP cell lines, which do not have the amplification. The findings suggest that one of the mechanisms underlying the overexpression of the uPA is the amplification of the gene, which is associated with the increased invasive potential of the cells.


Asunto(s)
Neoplasias de la Próstata/patología , Activador de Plasminógeno de Tipo Uroquinasa/genética , Northern Blotting , Amplificación de Genes , Humanos , Hibridación Fluorescente in Situ , Masculino , Hibridación de Ácido Nucleico , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/genética , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Células Tumorales Cultivadas
8.
Antioxid Redox Signal ; 3(1): 147-56, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11291593

RESUMEN

Changes occur in gene expression during aging in vivo and in replicative senescence in vitro, suggesting that aging can affect gene regulation. We have recently observed age-related changes in ubiquitously expressed, oxidative stress-responsive nuclear factor-kappa B (NF-kappa B) pathway during aging. Here we report a significant age-related increase in nuclear NF-kappa B binding activity together with increased protein levels of p52 and p65 components in rat liver. An additional, higher molecular weight protein band seen in their western blots suggests that their post-translational modification (but not phosphorylation) occurs in liver, which might affect their nuclear localization and binding activity during aging. However, aging did not affect the protein levels of the main I kappa B inhibitors (I kappa B alpha and I kappa B beta) or I kappa B kinase (IKK)-complex subunits (IKK alpha, -beta, and -gamma) involved in NF-kappa B activation. In addition, the level of Ser32-phosphorylated I kappa B alpha was unaffected by age, suggesting that neither the IKK complex nor altered level of the main inhibitors is involved in the observed up-regulation of NF-kappa B binding activity. Furthermore, the expression of NF-kappa B mRNAs (p50, p52, p65, and c-rel) and the mRNAs of their inhibitors (I kappa B alpha and I kappa B beta) did not show any statistically significant age-related changes. These results indicate that the expression level of NF-kappa B genes is not significantly affected by aging. The up-regulation of constitutive nuclear NF-kappa B binding activity and increased levels of nuclear p52 and p65 proteins might affect the expression of some NF-kappa B target genes in the aging liver.


Asunto(s)
Envejecimiento/metabolismo , Proteínas de Unión al Calcio , Hígado/metabolismo , FN-kappa B/metabolismo , Animales , Northern Blotting , Western Blotting , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Regulación de la Expresión Génica , Glicoproteínas de Membrana/metabolismo , FN-kappa B/antagonistas & inhibidores , Proteínas del Tejido Nervioso/metabolismo , Regiones Promotoras Genéticas , Ratas , Ratas Wistar , Sinaptotagmina I , Sinaptotagminas , Transfección , Regulación hacia Arriba
9.
Exp Cell Res ; 248(1): 194-202, 1999 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-10094826

RESUMEN

The ability of cells to adapt to environmental stresses undergoes a progressive reduction during aging. NF-kappaB-mediated signaling is a major defensive system against various environmental challenges. The aim of this study was to find out whether replicative senescence affects the response of the NF-kappaB signaling pathway to UVB light in human WI-38 and IMR-90 fibroblasts. The exposure of early passage fibroblasts to UVB light inhibited the proliferation and induced a flat phenotype similar to that observed in replicatively senescent fibroblasts not exposed to UVB light. The UVB radiation dose used (153 mJ/cm2) did not induce apoptosis in either early or late passage WI-38 fibroblasts. UVB exposure induced a prominent activation of the NF-kappaB signaling pathway both in early and in late passage WI-38 and IMR-90 fibroblasts. Interestingly, the response to UVB light was significantly attenuated in late passage fibroblasts. This attenuation was most prominent in DNA binding activities of nuclear NF-kappaB complexes. Similar senescence-related attenuation was also observed in the DNA binding activities of nuclear AP-1 and Sp-1 factors after UVB treatment. Immunoblotting and -cytochemistry showed an increase in nuclear localization of p50 and p65 components of NF-kappaB complexes. Supershift experiments showed that the specific NF-kappaB complexes contain p50 and p65 protein components but not p52 and c-Rel proteins. Cytoplasmic IkappaBalpha showed a marked decrease at protein level but an increase in phosphorylation after UVB treatment. Transient transfection assays with TK5-CAT and TK10-CAT plasmids carrying NF-kappaB-responsive sites of the TNFalpha promoter were used to analyze the functional activity of the NF-kappaB complexes. Results showed that UVB exposure induced an increase in NF-kappaB-driven CAT expression both in early and in late passage fibroblasts though the response was significantly stronger in early passage fibroblasts. Our results show that the induction of NF-kappaB-mediated signaling by UVB light is highly attenuated in senescent fibroblasts. This attenuation may reduce the stress resistance during cellular senescence.


Asunto(s)
Senescencia Celular/fisiología , FN-kappa B/metabolismo , Transducción de Señal , Benzoquinonas , Línea Celular , Línea Celular Transformada , Inhibidores Enzimáticos/farmacología , Fibroblastos/citología , Fibroblastos/metabolismo , Fibroblastos/fisiología , Fibroblastos/efectos de la radiación , Humanos , Lactamas Macrocíclicas , Inhibidores de Proteínas Quinasas , Quinonas/farmacología , Rifabutina/análogos & derivados , Tirfostinos/farmacología , Rayos Ultravioleta
10.
Biochem Biophys Res Commun ; 238(3): 712-6, 1997 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-9325154

RESUMEN

During aging and cellular senescence mutations accumulate in genomic and mitochondrial DNA. Ku autoantigens, DNA-dependent protein kinase, and poly (ADP-ribose) polymerase have an essential role in DNA damage recognition. Our purpose was to find out whether cellular senescence of fibroblasts affects the protein components that recognize DNA damage and induce the repair process. We compared presenescent and replicatively senescent human WI-38 fibroblasts with each other and with SV-40 immortalized and serum-deficient quiescent WI-38 cells. Our results showed that replicative senescence significantly decreased the nuclear level of both p70 and p86 components of Ku autoantigen. SV-40 immortalization and cellular quiescence did not affect the level of the p86 component but slightly increased that of p70. Both replicative senescence and cellular quiescence decreased the activity of DNA-dependent protein kinase in WI-38 fibroblasts. On the other hand, SV-40 immortalization increased the activity of DNA-dependent protein kinase. The protein level of poly(ADP-ribose) polymerase (PARP) was strongly decreased in replicatively senescent fibroblasts. Quiescence of early-passage fibroblasts also slightly reduced the protein level of PARP. Apoptosis was not observed in replicatively senescent fibroblasts. Our results show that replicative senescence and to some extent cellular quiescence down-regulate the recognition system of DNA damage involving Ku autoantigens, DNA-dependent protein kinase, and PARP and hence could enhance the accumulation of DNA damage during aging.


Asunto(s)
Antígenos Nucleares , Autoantígenos/metabolismo , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo/fisiología , Proteínas Nucleares/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Secuencia de Aminoácidos , Autoantígenos/genética , Autoantígenos/fisiología , Línea Celular , Senescencia Celular/genética , Senescencia Celular/inmunología , Fragmentación del ADN , Proteína Quinasa Activada por ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Fibroblastos , Humanos , Autoantígeno Ku , Pulmón/citología , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/fisiología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/fisiología
11.
Neurosci Lett ; 225(1): 61-4, 1997 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-9143018

RESUMEN

Aging process involves an increase in stress at cellular level. We studied whether aging affects the regulation of stress responsive transcription factor NF-kappa B in brain samples of Wistar rats. Hippocampus, cerebellum, and temporal and frontal lobes of cortex were studied. We observed a significant up-regulation in the constitutive, nucleus-located NF-kappa B binding activity in 30-month-old Wistar rats compared to young and 18-month-old rats. The increase was most prominent in cerebellum and in frontal cortex, but age-related changes did not occur in hippocampus. Inducible, cytoplasmic NF-kappa B binding activity was not affected by aging in any of the samples studied. Western blot assays did not show any age-related changes in the nuclear level of p50, p52, and p65 protein components of NF-kappa B complex. Cytoplasmic level of inhibitory I kappa B-alpha was also unaffected. The increase in nuclear constitutive NF-kappa B binding activity during aging may be related to the NF-kappa B driven cellular response to adapt neurons against apoptotic pressure, as observed recently in several apoptotic conditions.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Regulación de la Expresión Génica/fisiología , FN-kappa B/genética , Proteínas del Tejido Nervioso/genética , Animales , Cerebelo/metabolismo , Femenino , Lóbulo Frontal/metabolismo , Hipocampo/metabolismo , Masculino , Unión Proteica , Ratas , Ratas Wistar , Lóbulo Temporal/metabolismo , Regulación hacia Arriba
12.
Med Ref Serv Q ; 16(4): 1-18, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-10176645

RESUMEN

The Cushing/Whitney Medical Library began providing end-user access to MEDLINE in 1986 and switched to the OVID system in 1993. MEDLINE is a core service of the library, and the choice of delivery systems has had a significant impact throughout the Yale-New Haven Medical Center. This paper describes the user response to MEDLINE, discusses the effects of MEDLINE on other library services, and suggests ways in which technology, policy, and funding have influenced use. Yale's experience suggests that removing barriers in all three areas can dramatically expand the points of access, the number of users, and the amount of use with manageable effects on other library services.


Asunto(s)
Bibliotecas Médicas/organización & administración , Servicios de Biblioteca/tendencias , MEDLINE/estadística & datos numéricos , Centros Médicos Académicos , Connecticut , Costos y Análisis de Costo/estadística & datos numéricos , Bibliotecas Médicas/economía , Servicios de Biblioteca/economía , Servicios de Biblioteca/estadística & datos numéricos , MEDLINE/economía , Interfaz Usuario-Computador
13.
Biochem Biophys Res Commun ; 229(1): 36-43, 1996 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-8954080

RESUMEN

Terminal differentiation of myocytes involves withdrawal from the cell cycle, induction of myogenin expression, and finally formation of myotubes. To study the factors that regulate the initial phase of muscle differentiation, we analyzed the binding activities of transcription factors AP-1, Sp-1, and NF-kappa B in L6, C2C12, and rhabdomyosarcoma BA-Han-1C cells. Temporal changes in transcription factor binding activities were compared to the activation of myogenin promoter-driven CAT reporter gene and the expression level of myogenin, a master gene of myogenic differentiation. We observed a prominent decrease in the nuclear binding activities of AP-1, Sp-1, and NF-kappa B already 12 to 24 h after the transfer of cells to differentiation medium. The response was very similar in L6 and C2C12 myocytes and in BA-Han-1C rhabdomyosarcoma cells. The down-regulation clearly preceded the activation of myogenin promoter and the induction of myogenin and retinoblastoma expression, as well as the initiation of myocyte fusion. Cholera toxin and okadaic acid, established inhibitors of myogenin expression and muscle differentiation, strongly up-regulated the binding activities of AP-1, Sp-1, and NF-kappa B in differentiation medium. Myogenin expression and myocyte fusion were also inhibited. Levels of nuclear c-Fos and c-Jun proteins, components of the AP-1 complex, showed a prominent decrease already after 12 h in differentiation medium. These results show that the down-regulation of the proliferation-promoting transcription factors is a prerequisite to the initiation of myocyte differentiation.


Asunto(s)
Regulación hacia Abajo , Desarrollo de Músculos , Músculo Esquelético/crecimiento & desarrollo , FN-kappa B/metabolismo , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción AP-1/metabolismo , Animales , Diferenciación Celular , Fusión Celular , Toxina del Cólera/farmacología , Ratones , Músculo Esquelético/citología , Miogenina/biosíntesis , Ácido Ocadaico/farmacología , Unión Proteica , Ratas , Proteína de Retinoblastoma/biosíntesis , Células Tumorales Cultivadas , Regulación hacia Arriba
14.
Biochem Biophys Res Commun ; 226(2): 403-6, 1996 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-8806647

RESUMEN

Functional capacity of mitochondria declines during aging and this impairment may have a major role in aging process. Several observations indicate that transcriptional efficiency is reduced during aging. Our purpose was to find out whether aging and cellular senescence affect the nuclear binding activities of transcription factors which bind to OXBOX-REBOX sequence present in promoter regions of numerous nuclear genes encoding mitochondrial proteins. These factors regulate and coordinate the expression of mitochondrial proteins. We observed a strong down-regulation in the nuclear binding activities of OXBOX-REBOX factors in replicatively senesced human WI-38 and IMR-90 fibroblasts. On the contrary, SV-40 immortalization highly increased the nuclear binding activities. A considerable down-regulation of OXBOX-REBOX factors was also observed in UVB-irradiated WI-38 fibroblasts. Irradiation induced photoaging in fibroblasts which involved cell cycle arrest and senescent morphology. Interestingly, the nuclear binding activities of OXBOX-REBOX factors were also prominently decreased in the liver of Wistar rats at the age of 30 months but not yet at the age of 18 months. Our results suggest that the down-regulation of OXBOX-REBOX factors could affect the expression level of mitochondrial proteins encoded in nucleus and hence induce disturbances in mitochondrial function and promote the cellular aging process.


Asunto(s)
Senescencia Celular , Regulación hacia Abajo , Proteínas Nucleares/metabolismo , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Línea Celular Transformada , ADN , Humanos , Datos de Secuencia Molecular , Unión Proteica , Ratas , Ratas Wistar
15.
Biochem J ; 318 ( Pt 2): 603-8, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8809053

RESUMEN

Both the aging of animals and the senescence of cultured cells involve an altered pattern of gene expression, suggesting changes in transcription factor regulation. We studied age-related changes in transcription factors nuclear factor (NF)-kappa B, activator protein factor-1 (AP-1) and Sp-1 by using electrophoretic mobility shift binding assays; we also analysed changes in the protein components of NF-kappa B complex with Western blot assays. Nuclear and cytoplasmic extracts were prepared from heart, liver, kidney and brain of young adult and old NMRI mice and Wistar rats as well as from presenescent, senescent and simian virus 40-immortalized human WI-38 fibroblasts. Aging of both mice and rats induced a strong and consistent increase in the nuclear binding activity of NF-kappa B factor in all tissues studied, whereas those of AP-1 and Sp-1 decreased, e.g. in liver. Protein levels of p50, p52 and p65 components of the NF-kappa B complex did not show any age-associated changes in the cytoplasmic fraction but in the nuclear fraction the level of p52 strongly increased in heart and liver during aging. The protein levels of inhibitory I kappa B-alpha and Bcl-3 components were not affected by aging in any of the tissues studied. Replicative cellular senescence of human WI-38 fibroblasts induced a strong decrease in nuclear NF-kappa B, AP-1 and Sp-1 binding activities. Protein levels of p50 and p52 components of NF-kappa B complex were decreased in the nuclear fraction of senescent WI-38 fibroblasts but in the cytoplasm of senescent fibroblasts the level of p65 protein was increased. Cellular senescence also slightly decreased the protein levels of I kappa B-alpha and Bcl-3. Transfection assays with NF-kappa B-enhancer-driven chloramphenicol acetyltransferase reporter gene showed a significant down-regulation of NF-kappa B promoter activity in senescent WI-38 fibroblasts. Results suggest that the aging process might be regulated differently in tissues and cultured fibroblasts, perhaps reflecting differences between mitotic and post-mitotic cells. In tissues, aging seems to involve specific changes in the regulation of NF-kappa B components and perhaps also changes in the DNA-binding affinities of the NF-kappa B complex.


Asunto(s)
Envejecimiento/metabolismo , Senescencia Celular , Regulación del Desarrollo de la Expresión Génica , Hígado/metabolismo , Miocardio/metabolismo , FN-kappa B/biosíntesis , Animales , Western Blotting , División Celular , Línea Celular , Línea Celular Transformada , Femenino , Corazón/crecimiento & desarrollo , Humanos , Hígado/crecimiento & desarrollo , Pulmón , Masculino , Ratones , Ratas , Ratas Wistar , Proteínas Recombinantes/biosíntesis , Virus 40 de los Simios , Transfección
16.
J Mol Cell Cardiol ; 28(3): 487-98, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9011632

RESUMEN

The accumulation of lipofuscin to cardiomyocytes is a classical parameter of aging and is believed to reflect oxidative stress. NF-kB transcription factor complex is one of the cellular sensors which responds to oxidative stress and regulates gene expression. Our purpose was to study whether aging affects the level and distribution of DNA binding activities of NF-kB transcription factors both in cardiac sarcoplasm and nuclear extracts. We used electrophoretic mobility shift assays (EMSA) to characterize the DNA binding activities of NF-kB and two other transcription factors. AP-1 and Sp-1, in the myocardium of 4 months and 24 months old male and female NMRI-mice. The protein levels of p50, p52, and p65 components of NF-kB-complex and an inhibitory IkB-alpha/MAD-3 were assayed with Western blots. Surprisingly, aging upregulated by 123% the nuclear NF-kB binding activity in the male and female mice. The sarcoplasmic NF-kB activity, activated by deoxycholate, did not show any change during aging. Aging-induced increase in nuclear NF-kB protein-DNA binding activity was observed both by gel retardation and UV-crosslinking assays. In immunoblotting, the level of p52 component but not those of p50 and p65 components of NF-kB-complex was slightly increased in nuclear fractions. Aging did not affect the sarcoplasmic levels of p50, p52, and p65 proteins. Supershift EMSA assays showed that the nuclear NF-kB complex contained p50, p52, and p65 components. The level of inhibitory IkB-alpha/MAD-3 protein was unaffected by aging both in nuclear and sarcoplasmic fractions. Aging down-regulated the nuclear Sp-1 binding activities but did not affect AP-1 binding activities. Statistically significant sex-related differences did not appear in the aging responses of transcription factors. These results indicate that NF-kB transcription factor pathway is activated during aging in cardiac muscle and could be the signaling route regulating gene expression. However, the activation mechanism of NF-kB during aging whether oxidative stress responsive or not in vivo needs further studies.


Asunto(s)
Envejecimiento/metabolismo , Proteínas I-kappa B , Miocardio/metabolismo , FN-kappa B/metabolismo , Animales , Núcleo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación hacia Abajo , Femenino , Masculino , Ratones , Inhibidor NF-kappaB alfa , Subunidad p50 de NF-kappa B , Estrés Oxidativo , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción ReIA , Regulación hacia Arriba
17.
Eur J Biochem ; 220(2): 615-21, 1994 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8125122

RESUMEN

Using avidin cDNA as a hybridisation probe, we detected a gene family whose putative products are related to the chicken egg-white avidin. Two overlapping genomic clones were found to contain five genes (avidin-related genes 1-5, avr1-avr5), which have been cloned, characterized and sequenced. All of the genes have a four-exon structure with an overall identity with the avidin cDNA of 88-92%. The genes appear to have no pseudogenic features and, in fact, two of these genes have been shown to be transcribed. The putative proteins share a sequence identity of 68-78% with avidin. The amino acid residues responsible for the biotin-binding activity of avidin and the bacterial biotin-binding protein, streptavidin, are highly conserved. Since avidin is induced in both a progesterone-specific manner and in connection with inflammation, these genes offer a valuable tool to study complex gene regulation in vivo.


Asunto(s)
Avidina/genética , Pollos/genética , Secuencia de Aminoácidos , Animales , Avidina/química , Avidina/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Biotina/metabolismo , Clonación Molecular/métodos , Secuencia Conservada , ADN/genética , ADN/aislamiento & purificación , Exones , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Precursores de Proteínas/química , Precursores de Proteínas/genética , Seudogenes , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Estreptavidina , Transcripción Genética
18.
Dev Med Child Neurol ; 30(5): 571-89, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2465930

RESUMEN

Background factors of developmental outcome in a group of 386 neonatal 'at-risk' infants and 107 controls were examined in a prospective nine-year follow-up study. Dichotomized outcome variables were computed for each of the assessments; neurodevelopmental, motor, psycholinguistic, cognitive and school progress. In the study group, 17 to 29 per cent were found to have significant problems, compared with 10 to 17 per cent of the control group. Children with low birthweight, neonatal neurological symptoms or several neonatal disorders were found to have most problems at the age of nine years. In stepwise logistic regression analyses, smallness for gestational age, neonatal signs of cerebral depression and low social-class were found to be the most significant predictors of neurodevelopmental problems at age nine. Factors suggesting intra-uterine hypoxia or poor nutrition were also associated with developmental problems. The background pathology of the neonatal conditions seemed to be of more importance than the neonatal manifestations themselves.


Asunto(s)
Encefalopatías/etiología , Encéfalo/crecimiento & desarrollo , Discapacidades del Desarrollo/etiología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Edad Gestacional , Crecimiento , Humanos , Lactante , Recién Nacido , Pruebas de Inteligencia , Masculino , Pruebas Neuropsicológicas , Embarazo , Complicaciones del Embarazo , Factores de Riesgo , Clase Social
20.
Acta Paediatr Scand ; 73(6): 835-41, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6240892

RESUMEN

A nine-year follow-up of 116 children born consecutively in 1971-74 with a birthweight of 1 500 g or less showed that 59 had died. Of those who were alive, four had severe motor and/or mental handicaps and three were blind because of retrolental fibroplasia. The low birthweight children without severe handicaps were found to have impaired motor function, speech defects and impaired school achievement more often than the controls. There was a significant correlation between the test results at the age of five and nine years, which indicates that children with school failure can be recognized and early remedial treatment started before school or on starting school.


Asunto(s)
Desarrollo Infantil , Recién Nacido de Bajo Peso , Destreza Motora , Peso al Nacer , Niño , Preescolar , Personas con Discapacidad , Femenino , Estudios de Seguimiento , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Trastornos Mentales/etiología , Embarazo , Pronóstico , Riesgo
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