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1.
Oncogene ; 32(3): 352-62, 2013 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-22410778

RESUMEN

The Warburg effect in cancer cells has been proposed to involve several mechanisms, including adaptation to hypoxia, oncogenes activation or loss of oncosuppressors and impaired mitochondrial function. In previous papers, it has been shown that K-ras transformed mouse cells are much more sensitive as compared with normal cells to glucose withdrawal (undergoing apoptosis) and present a high glycolytic rate and a strong reduction of mitochondrial complex I. Recent observations suggest that transformed cells have a derangement in the cyclic adenosine monophosphate/cAMP-dependent protein kinase (cAMP/PKA) pathway, which is known to regulate several mitochondrial functions. Herein, the derangement of the cAMP/PKA pathway and its impact on transformation-linked changes of mitochondrial functions is investigated. Exogenous stimulation of PKA activity, achieved by forskolin treatment, protected K-ras-transformed cells from apoptosis induced by glucose deprivation, enhanced complex I activity, intracellular adenosine triphosphate (ATP) levels, mitochondrial fusion and decreased intracellular reactive oxygen species (ROS) levels. Several of these effects were almost completely prevented by inhibiting the PKA activity. Short-time treatment with compounds favoring mitochondrial fusion strongly decreased the cellular ROS levels especially in transformed cells. These findings support the notion that glucose shortage-induced apoptosis, specific of K-ras-transformed cells, is associated to a derangement of PKA signaling that leads to mitochondrial complex I decrease, reduction of ATP formation, prevalence of mitochondrial fission over fusion, and thereby opening new approaches for development of anticancer drugs.


Asunto(s)
Colforsina/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes ras/genética , Mitocondrias/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Adenosina Trifosfato/biosíntesis , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Respiración de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Fibroblastos/citología , Glucosa/farmacología , Humanos , Ratones , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo
2.
Oncogene ; 27(13): 1853-64, 2008 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-17906697

RESUMEN

The combination of an increase in the cAMP-phosphodiesterase activity of h-prune and its interaction with nm23-H1 have been shown to be key steps in the induction of cellular motility in breast cancer cells. Here we present the molecular mechanisms of this interaction. The region of the nm23-h-prune interaction lies between S120 and S125 of nm23, where missense mutants show impaired binding; this region has been highly conserved throughout evolution, and can undergo serine phosphorylation by casein kinase I. Thus, the casein kinase I delta-epsilon specific inhibitor IC261 impairs the formation of the nm23-h-prune complex, which translates 'in vitro' into inhibition of cellular motility in a breast cancer cellular model. A competitive permeable peptide containing the region for phosphorylation by casein kinase I impairs cellular motility to the same extent as IC261. The identification of these two modes of inhibition of formation of the nm23-H1-h-prune protein complex pave the way toward new challenges, including translational studies using IC261 or this competitive peptide 'in vivo' to inhibit cellular motility induced by nm23-H1-h-prune complex formation during progression of breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteínas Portadoras/metabolismo , Movimiento Celular , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Nucleósido Difosfato Quinasas NM23/metabolismo , Animales , Unión Competitiva , Neoplasias de la Mama/genética , Células COS , Caenorhabditis elegans/embriología , Caenorhabditis elegans/metabolismo , Proteínas Portadoras/genética , Comunicación Celular , Chlorocebus aethiops , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/genética , Drosophila melanogaster/embriología , Drosophila melanogaster/metabolismo , Humanos , Indoles/farmacología , Nucleósido Difosfato Quinasas NM23/genética , Fragmentos de Péptidos/farmacología , Floroglucinol/análogos & derivados , Floroglucinol/farmacología , Hidrolasas Diéster Fosfóricas/metabolismo , Monoéster Fosfórico Hidrolasas , Fosforilación , Xenopus laevis/embriología , Xenopus laevis/metabolismo
3.
Biotechniques ; 35(2): 384-8, 390-1, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12951781

RESUMEN

High-throughput protein expression and purification are major bottlenecks in the postgenomic and proteomic era. We show here an automated method to express and purify nm23-H2, a nucleoside diphosphate kinase (NDPK), in a 96-well format, by the use of a robotic workstation, from insect Spodoptera frugiperda (Sf9) baculovirus-infected cells using nickel-nitrilotriacetic acid (Ni-NTA) agarose beads. The automated method is coupled to mass spectrometry for a validation and quality-control analysis. To verify the bona fide of the recombinant protein, several tests have been produced, including NDPK assay, Western blotting, and in vitro phosphorylation experiments, thus confirming the value of the protocol developed. The method has been validated for the expression of several proteins, thus confirming the value of this automated protocol. The research presented here is a useful method both for industrial and academic environments to produce in a high-throughput mode recombinant eukaryotic proteins to be assayed for a specific function in a systematic manner.


Asunto(s)
Baculoviridae , Proteínas/aislamiento & purificación , Proteínas/metabolismo , Animales , Western Blotting , Caseína Quinasas , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Peso Molecular , Mutación , Nucleósido Difosfato Quinasas NM23 , Nucleósido-Difosfato Quinasa/metabolismo , Fosforilación , Proteínas Quinasas/metabolismo , Proteínas/genética , Proteínas Recombinantes/análisis , Reproducibilidad de los Resultados , Robótica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Spodoptera/virología
4.
J Trauma ; 31(1): 140-2, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1986121

RESUMEN

Duplications of the genitourinary tract are uncommon and may be a source of confusion in the early diagnosis of ureteral trauma when their presence is not suspected. We present a case of delayed diagnosis of a penetrating injury to a duplicated ureter and its management.


Asunto(s)
Uréter/anomalías , Heridas por Arma de Fuego/diagnóstico , Adulto , Humanos , Masculino , Radiografía , Uréter/diagnóstico por imagen , Uréter/lesiones , Heridas por Arma de Fuego/diagnóstico por imagen
5.
J Surg Oncol ; 45(3): 207-11, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2232813

RESUMEN

A patient developing a colonic adenoma 38 years following ureterosigmoidostomy is presented. The mechanisms of neoplastic transformation associated with ureterosigmoidostomy is now better understood. This knowledge is being applied to develop modifications both of the surgical technique and the management of patients with this form of urinary diversion, and is a subject of discussion.


Asunto(s)
Adenoma/etiología , Colon Sigmoide/cirugía , Neoplasias del Colon/etiología , Complicaciones Posoperatorias/etiología , Ureterostomía/efectos adversos , Derivación Urinaria/efectos adversos , Adulto , Humanos , Masculino , Factores de Tiempo
6.
J Urol ; 142(2 Pt 1): 293-6, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2664221

RESUMEN

We describe a new sphincter mechanism and its clinical application in 11 patients requiring continent diversion. The sphincter, composed of 2 short segments of ileum, is urodynamically responsive and actually increases its resistance to leakage when reservoir pressure or volume increases. Because of this dynamic continence control and its ease of construction, it appears to be a useful addition to the reconstructive urological armamentarium.


Asunto(s)
Derivación Urinaria/métodos , Colon/cirugía , Femenino , Humanos , Íleon/cirugía , Masculino , Persona de Mediana Edad , Presión , Técnicas de Sutura , Neoplasias de la Vejiga Urinaria/cirugía , Vejiga Urinaria Neurogénica/cirugía , Cateterismo Urinario , Urodinámica
7.
J Antimicrob Chemother ; 23 Suppl D: 35-8, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2722722

RESUMEN

This study evaluates the safety and efficacy of cefmetazole in comparison with cefoxitin in the parenteral treatment of patients hospitalized with acute urinary tract infections. Of the 49 evaluable patients, 27 were randomized to cefmetazole and 22 to cefoxitin. There was clinical success in 26 (96%) patients and bacteriological cure in 22 (81%) patients receiving cefmetazole. This compares with clinical success in 21 (95%) patients and bacteriological cure in 17 (77%) patients randomized to cefoxitin. There were no adverse reactions associated with either antibiotic. This study indicates that the clinical and bacteriological outcome was similar.


Asunto(s)
Cefmetazol/uso terapéutico , Cefoxitina/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cefmetazol/efectos adversos , Cefoxitina/efectos adversos , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Distribución Aleatoria , Infecciones Urinarias/microbiología
8.
Urology ; 32(4): 285-7, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2972104

RESUMEN

Transrectal ultrasonography has proved valuable in assessing the effect of primary treatment modalities for prostate carcinoma. This study shows patients who had a significant reduction in primary tumor volume had a significantly better prognosis and had less local symptoms than did the group of patients that did not have a significant reduction (less than 50%) in primary volume secondary to therapy. Patients were treated with either castration or Zoladex and all had Stage D2 cancer of the prostate.


Asunto(s)
Buserelina/análogos & derivados , Carcinoma/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Buserelina/uso terapéutico , Carcinoma/patología , Hormona Liberadora de Gonadotropina/análogos & derivados , Goserelina , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/patología , Ultrasonografía
10.
J Surg Oncol ; 37(4): 252-6, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3361918

RESUMEN

Urinary diversion utilizing a continence-maintaining ileal valve has been performed in 12 canines. This procedure offers a simple surgical procedure and uses the diversion's internal fluid pressure to maintain continence. Of 12 canines with this continence-maintaining ileal valve, 11 remained continent at sacrifice. Operative complications were minimal and late complications occurred in 2 dogs. Histological evaluation of the diversionary tissues revealed slight changes in the mucosa of the ileal valve, with some flattening of the villi. This procedure may have a clinical role in urinary diversion for patients with pelvic malignancy or patients who need urinary diversion for other reasons.


Asunto(s)
Derivación Urinaria/métodos , Incontinencia Urinaria/terapia , Animales , Perros , Femenino , Ileostomía/métodos , Íleon/cirugía
11.
J Urol ; 138(4 Pt 2): 996-9, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3309378

RESUMEN

We describe a new operation to create a continent, catheterizable urinary sphincter from a short segment of ileum. The sphincter has provided continence over a wide range of bladder pressures in dogs and it may be adapted to a variety of clinical continence requirements.


Asunto(s)
Cistostomía/métodos , Íleon/cirugía , Cateterismo Urinario , Animales , Perros , Femenino , Íleon/patología , Presión , Técnicas de Sutura , Urodinámica
12.
J Urol ; 136(1 Pt 2): 336-8, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3723684

RESUMEN

We compared experimental ligature-induced ureteropelvic junction obstruction in the dog with naturally occurring ureteropelvic junction obstruction in children to determine if clinical behavior and difficulties in diagnosis could be related to different types or components of obstruction at the ureteropelvic junction. Measurements of flow rate out of the ligature-obstructed canine renal pelvis demonstrated a pressure-dependent pattern in which flow increased linearly in response to increasing pressures. In 5 human kidneys with intrinsic ureteropelvic junction obstruction a similar pressure-dependent pattern was demonstrated. This was in contrast to 6 human kidneys with extrinsic mechanical ureteropelvic junction obstruction in which a volume-dependent pressure flow pattern occurred, such that urinary flow rate did not keep pace with increases in pelvic pressure. In some cases flow actually decreased at high pressures because the ureteropelvic junction became self-obstructing as the pelvis enlarged. These findings indicate that the precise pathological anatomy of the ureteropelvic junction defines the pattern of flow across the obstruction. The 2 different types of obstruction, pressure-dependent and volume-dependent flow restrictions, which exist are important determinants of the clinical behavior of the obstructed kidney insofar as its potential for progressive hydronephrosis. They also help to explain why diagnostic tests for assessing obstruction in hydronephrosis are inaccurate at times.


Asunto(s)
Hidronefrosis/fisiopatología , Pelvis Renal/fisiopatología , Obstrucción Ureteral/fisiopatología , Animales , Niño , Preescolar , Perros , Femenino , Humanos , Hidronefrosis/diagnóstico , Lactante , Recién Nacido , Masculino , Presión , Obstrucción Ureteral/diagnóstico , Micción
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