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1.
Int J Impot Res ; 29(3): 115-119, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28298622

RESUMEN

Hyperlipidemia is an important risk factor for atherosclerosis and is frequently seen in patients with erectile dysfunction (ED). This study was designed to evaluate whether the acute effect of native low-density lipoprotein (nLDL) on intracavernosal pressure (ICP) is reversible and related to plasma asymmetrical dimethylarginine (ADMA), endogenous inhibition of endothelial nitric oxide synthase (eNOS) levels and eNOS expression in cavernous tissues. Hyperlipidemia was induced by a single dose of intravenous 4 mg kg-1 nLDL. Experiments were performed 72 h (72H), 2 weeks (2W) and 8 weeks (8W) after nLDL injection. Endothelium-dependent relaxations, the ratio of ICP to mean arterial pressure (MAP; ICP/MAP), plasma ADMA levels and eNOS mRNA and protein levels were evaluated. The ICP/MAP ratio decreased in both the 2W and 8W groups. Endothelium-dependent relaxation responses to acetylcholine in the rat thoracic aorta were damaged in the 8W group. Plasma ADMA levels increased in the 8W group. mRNA expression of eNOS decreased in a time-dependent manner, whereas the protein expression increased. These results suggest that acute nLDL injection-induced impairments in erectile functions during an 8-week period are irreversible and might be related to an increase in ADMA levels and changes in the regulation of the eNOS/NO pathway.


Asunto(s)
Arginina/análogos & derivados , Endotelio Vascular/fisiopatología , Disfunción Eréctil/etiología , Lipoproteínas LDL/efectos adversos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Animales , Arginina/sangre , Modelos Animales de Enfermedad , Disfunción Eréctil/sangre , Disfunción Eréctil/fisiopatología , Hiperlipidemias/complicaciones , Lipoproteínas LDL/sangre , Masculino , Ratas Wistar , Factores de Tiempo
2.
J Int Med Res ; 35(6): 867-72, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18034999

RESUMEN

Vangl2 (Van Gogh-like 2) protein acts via non-canonical Wnt signalling to regulate polarized cell movements during development of the proximal outflow tract in vertebrate embryos. Recently, it has been shown that mutations of the Vangl2 gene cause aortic arch defects that are characteristic of the loop-tail (Lp) mouse and they have also became a strong candidate for causing congenital outflow tract defects in humans. Thus, in this study Tetralogy of Fallot (ToF), which comprises a group of syndromes that constitutes the most frequent cause of congenital cardiac outflow abnormalities in humans, was analysed for mutations within all coding regions of the Vangl2 gene. Based on direct sequencing data from a combination of 20 patients with ToF and 22 healthy people, three polymorphisms have been identified in exon 6 and exon 7 which do not change the amino acid sequence. It was concluded, therefore, that there is no specific mutation responsible for the ToF phenotype in the Vangl2 gene.


Asunto(s)
Análisis Mutacional de ADN , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/genética , Tetralogía de Fallot/genética , Animales , Secuencia de Bases , Preescolar , Exones , Humanos , Lactante , Ratones , Polimorfismo Genético
3.
Biochimie ; 87(3-4): 343-51, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15781321

RESUMEN

Matrix metalloproteinases (MMP's) and tissue inhibitors of metalloproteinases (TIMP's) possess a preponderant role in the metabolism of the major extracellular matrix protein, collagen, and are thought to be important in the mechanism of tumor invasion. Lung cancer occupies the first position in mortality and the second position in incidence, among all cancers. In the present investigation, we studied the effect of basic fibroblast growth factor (bFGF) on collagen, matrix metalloproteinase-2 (MMP-2), and tissue metalloproteinase inhibitor-2 (TIMP-2) levels in normal and carcinoma lung tissue fibroblast cultures. MMP-2 was selected because of its high specificity in the degradation of type IV collagen, major component of the basal membrane. The effect of bFGF on MMP-2, TIMP-2, total collagen, and type I collagen levels of normal and carcinoma lung fibroblast cultures was investigated at 0, 10, and 100 ng/ml. Statistical analysis was carried out using the Mann-Whitney-U test and possible correlations were searched using the Spearman correlation analysis method. MMP-2, TIMP-2, total collagen, and type-1 collagen levels based on cell counts (10(3) cells) showed no statistically significant differences between the carcinoma and normal fibroblast cultures. However, positive correlations were found between MMP-2 and TIMP-2 in normal (P = 0.016) and carcinoma (P = 0.001) tissue fibroblast cultures. Positive correlations were also found between total collagen and TIMP-2 levels in normal and carcinoma tissue fibroblast cultures (P = 0.002 and P = 0.032). Total collagen and TIMP-2 levels also showed positive and strong correlations in all cultures except in 100 ng/ml bFGF concentrations. In addition, type I collagen and MMP-2 levels showed positive significant correlations only in normal and carcinoma control cultures, while type I collagen and TIMP-2 levels showed positive correlations in all cultures except carcinoma fibroblasts at 100 ng/ml bFGF. It may be concluded that bFGF does not affect MMP-2, TIMP-2, total collagen, and type-1 collagen levels in fibroblast cultures grown from human carcinoma and normal lung tissues. However, bFGF was noted, in vitro, to disturb the equilibrium which normally exists between the four parameters, both in normal and carcinoma tissue fibroblasts.


Asunto(s)
Carcinoma/patología , Colágeno Tipo I/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Fibroblastos/efectos de los fármacos , Neoplasias Pulmonares/patología , Metaloproteinasa 2 de la Matriz/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Fibroblastos/metabolismo , Humanos , Análisis de Regresión
4.
J Biol Chem ; 276(35): 32977-83, 2001 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-11435444

RESUMEN

Hepatocyte growth factor (HGF) is a secreted, heparan sulfate (HS) glycosaminoglycan-binding protein that stimulates mitogenesis, motogenesis, and morphogenesis in a wide array of cellular targets, including hepatocytes and other epithelial cells, melanocytes, endothelial cells, and hematopoietic cells. NK1 is an alternative HGF isoform that consists of the N-terminal (N) and first kringle (K1) domains of full-length HGF and stimulates all major HGF biological activities. Within NK1, the N domain retains the HS binding properties of full-length HGF and mediates HS-stimulated ligand oligomerization but lacks significant mitogenic or motogenic activity. In contrast, K1 does not bind HS, but it stimulates receptor and mitogen-activated protein kinase activation, mitogenesis, and motogenesis, demonstrating that structurally distinct and dissociable domains of HGF are the primary mediators of HS binding and receptor activation. Despite the absence of HS-K1 binding, K1 mitogenic activity in HS-negative cells is strictly dependent on added soluble heparin, whereas K1-stimulated motility is not. We also found that, like the receptors for fibroblast growth factors, the HGF receptor c-Met binds tightly to HS. These data suggest that HS can facilitate HGF signaling through interaction with c-Met that is independent of HGF-HS interaction and that the recruitment of specific intracellular effectors that mediate distinct HGF responses such as mitogenesis and motility is regulated by HS-c-Met interaction at the cell surface.


Asunto(s)
Heparitina Sulfato/química , Heparitina Sulfato/metabolismo , Factor de Crecimiento de Hepatocito/química , Factor de Crecimiento de Hepatocito/farmacología , Queratinocitos/fisiología , Proteínas Proto-Oncogénicas c-met/química , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal/fisiología , Animales , Sitios de Unión , División Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , ADN/biosíntesis , Perros , Heparitina Sulfato/aislamiento & purificación , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Riñón , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Fragmentos de Péptidos/farmacología , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Estructura Secundaria de Proteína , Proteínas Proto-Oncogénicas c-met/aislamiento & purificación
5.
J Biol Chem ; 276(17): 14308-14, 2001 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-11278639

RESUMEN

Hepatocyte growth factor (HGF) stimulates mitogenesis, motogenesis, and morphogenesis in a wide range of cellular targets during development, homeostasis and tissue regeneration. Inappropriate HGF signaling occurs in several human cancers, and the ability of HGF to initiate a program of protease production, cell dissociation, and motility has been shown to promote cellular invasion and is strongly linked to tumor metastasis. Upon HGF binding, several tyrosines within the intracellular domain of its receptor, c-Met, become phosphorylated and mediate the binding of effector proteins, such as Grb2. Grb2 binding through its SH2 domain is thought to link c-Met with downstream mediators of cell proliferation, shape change, and motility. We analyzed the effects of Grb2 SH2 domain antagonists on HGF signaling and observed potent blockade of cell motility, matrix invasion, and branching morphogenesis, with ED(50) values of 30 nm or less, but only modest inhibition of mitogenesis. These compounds are 1000-10,000-fold more potent anti-motility agents than any previously characterized Grb2 SH2 domain antagonists. Our results suggest that SH2 domain-mediated c-Met-Grb2 interaction contributes primarily to the motogenic and morphogenic responses to HGF, and that these compounds may have therapeutic application as anti-metastatic agents for tumors where the HGF signaling pathway is active.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Factor de Crecimiento de Hepatocito/metabolismo , Proteínas/metabolismo , Dominios Homologos src , Animales , Línea Celular , Movimiento Celular , Colágeno/metabolismo , ADN Complementario/metabolismo , Perros , Relación Dosis-Respuesta a Droga , Matriz Extracelular/metabolismo , Proteína Adaptadora GRB2 , Factor de Crecimiento de Hepatocito/química , Factor de Crecimiento de Hepatocito/genética , Humanos , Immunoblotting , Fosforilación , Pruebas de Precipitina , Estructura Terciaria de Proteína , Proteínas/antagonistas & inhibidores , Proteínas/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal , Factores de Tiempo , Transfección
6.
Dermatology ; 201(2): 158-61, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11053922

RESUMEN

A 73-year-old man with porokeratosis palmaris, plantaris et disseminata is presented. He had punctate, guttate and annular hyperkeratotic papular lesions widespread on his body with thorn-like hyperkeratosis on the palms and soles. Lesional skin did not show mutations of TP53 exons 5-6, 7, 8.


Asunto(s)
Poroqueratosis/patología , Proteína p53 Supresora de Tumor/genética , Adolescente , Anciano , ADN/genética , Salud de la Familia , Humanos , Masculino , Persona de Mediana Edad , Mutación , Linaje , Polimorfismo Conformacional Retorcido-Simple , Poroqueratosis/genética , Células Tumorales Cultivadas
7.
Int J Dermatol ; 39(4): 278-83, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10809977

RESUMEN

BACKGROUND: Borrelia burgdorferi (Bb) infection has been implicated in the development of morphea and lichen sclerosus; however, conflicting results have been reported with different investigational methods from different regions. We looked for evidence of Bb in patients with morphea and lichen sclerosus by polymerase chain reaction (PCR) analysis of of skin biopsy samples. METHODS: Formalin-fixed, paraffin-embedded skin biopsy samples from 10 patients with morphea and 12 patients with lichen sclerosus were investigated by PCR analysis for the presence of Bb. RESULTS: The presence of Bb DNA was demonstrated in three of 10 patients with morphea and six of 12 patients with lichen sclerosus by nested PCR. CONCLUSIONS: The data obtained in this study suggest that Bb may play a role in the etiopathogenesis of both morphea and lichen sclerosus at least in the western parts of Turkey.


Asunto(s)
Grupo Borrelia Burgdorferi/aislamiento & purificación , Liquen Escleroso y Atrófico/microbiología , Enfermedad de Lyme/microbiología , Esclerodermia Localizada/microbiología , Adolescente , Adulto , Anciano , Grupo Borrelia Burgdorferi/genética , Niño , Cartilla de ADN/química , ADN Bacteriano/análisis , Femenino , Humanos , Liquen Escleroso y Atrófico/patología , Enfermedad de Lyme/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Esclerodermia Localizada/patología , Piel/microbiología , Piel/patología
8.
Biochemistry ; 38(6): 1765-71, 1999 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-10026256

RESUMEN

Keratinocyte growth factor (KGF) is an unusual fibroblast growth factor (FGF) family member in that its activity is largely restricted to epithelial cells, and added heparin/heparan sulfate inhibits its activity in most cell types. The effects of heparan sulfate proteoglycan (HSPG) on binding and signaling by acidic FGF (aFGF) and KGF via the KGFR were studied using surface-bound and soluble receptor isoforms expressed in wild type and mutant Chinese hamster ovary (CHO) cells lacking HSPG. Low concentrations of added heparin (1 microgram/mL) enhanced the affinity of ligand binding to surface-bound KGFR in CHO mutants, as well as ligand-stimulated MAP kinase activation and c-fos induction, but had little effect on binding or signaling in wild type CHO cells. Higher heparin concentrations inhibited KGF, but not aFGF, binding and signaling. In addition to the known interaction between HSPG and KGF, we found that the KGFR also bound heparin. The biphasic effect of heparin on KGF, but not aFGF, binding and signaling suggests that occupancy of the HSPG binding site on the KGFR may specifically inhibit KGF signaling. In contrast to events on the cell surface, added heparin was not required for high-affinity soluble KGF-KGFR interaction. These results suggest that high-affinity ligand binding is an intrinsic property of the receptor, and that the difference between the HSPG-dependent ligand binding to receptor on cell surfaces and the HSPG-independent binding to soluble receptor may be due to other molecule(s) present on cell surfaces.


Asunto(s)
Factores de Crecimiento de Fibroblastos , Sustancias de Crecimiento/fisiología , Proteoglicanos de Heparán Sulfato/fisiología , Queratinocitos/fisiología , Receptores de Factores de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento/fisiología , Transducción de Señal , Animales , Sitios de Unión/genética , Células CHO , Cricetinae , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Factor 10 de Crecimiento de Fibroblastos , Factor 7 de Crecimiento de Fibroblastos , Heparina/metabolismo , Heparina/farmacología , Heparitina Sulfato/metabolismo , Humanos , Fragmentos Fc de Inmunoglobulinas/genética , Fragmentos Fc de Inmunoglobulinas/metabolismo , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/metabolismo , Queratinocitos/metabolismo , Ligandos , Ratones , Ratones Endogámicos BALB C , Ratas , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento/genética , Receptores de Factores de Crecimiento/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Solubilidad , Transfección
9.
J Laryngol Otol ; 112(5): 494-6, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9747486

RESUMEN

A parotid gland mass with presenting features of malignancy is a diagnostic and therapeutic challenge. The histological nature of the lesion must be clearly determined before proceeding with facial nerve sacrificing surgery. Although rare, tuberculosis of the parotid gland must be included in the differential diagnosis of a parotid gland mass especially when the social characteristics of the patient suggests a mycobacterial infection. Primary tuberculosis of the parotid gland is generally encountered among populations with a high incidence of pulmonary disease. The difficulty in the differential diagnosis of a parotid gland malignancy may be helped by a high degree of clinical suspicion, since laboratory tests generally do not identify the specific causative organism. This article reports the first case of parotid gland tuberculosis with clinical and radiodiagnostical features simulating malignancy in which the diagnosis was confirmed by the polymerase chain reaction (PCR).


Asunto(s)
Enfermedades de las Parótidas/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Tuberculosis/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades de las Parótidas/microbiología , Neoplasias de la Parótida/diagnóstico
11.
Spine (Phila Pa 1976) ; 21(17): 1991-5, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8883200

RESUMEN

STUDY DESIGN: Twenty-five formaldehyde solution-fixed, paraffin-embedded tissue blocks from vertebral biopsy specimen materials with presumptive diagnosis of tuberculous spondylitis and nonspecific vertebral osteomyelitis were studied. OBJECTIVES: To evaluate the sensitivity and specificity of polymerase chain reaction in detecting Mycobacterium tuberculosis in formaldehyde solution-fixed, paraffin-embedded tissue samples from histologically proved tuberculous spondylitis. SUMMARY OF BACKGROUND DATA: Diagnosis of a mycobacterial infection is a long and tedious process; because of the slow growth rate of mycobacteria on solid media, identification and antibiotic sensitivity testing can take up to 10 weeks, but the sensitivity of culture can be as low as 50%. Direct microscopy is insensitive because clinical samples may contain only few organisms. Recently, polymerase chain reaction has been applied in the rapid amplification and identification of many organisms, including mycobacteria. METHODS: The DNAs were extracted from 25 paraffin-embedded tissue blocks. An insertion element IS 6110 (Integrated DNA Tec. Inc., Corrallville, IA), a DNA sequence unique to Mycobacterium complex (M. tuberculosis and the subspecies Mycobacterium bovis), was amplified by polymerase chain reaction. Polymerase chain reaction results were compared with those of Mycobacterium culture, acid-fast bacilli staining, and histologic findings. RESULTS: Polymerase chain reaction was positive in 18 cases of 19 tuberculous spondylitis. Three of the polymerase chain reaction test results were positive with concomitant negative culture and positive acid-fast bacilli staining. There were six chronic nonspecific infections, and polymerase chain reaction results were negative in five cases; in the single positive case, DNA amplification results remained positive even after three repeated tests. CONCLUSION: Polymerase chain reaction has a sensitivity of 94.7%, specificity of 83.3%, positive predictive value of 94.7%, and a negative predictive value of 83.3%. Accuracy was calculated as 92%.


Asunto(s)
Fijadores , Formaldehído , Mycobacterium tuberculosis/aislamiento & purificación , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Tuberculosis de la Columna Vertebral/microbiología , Humanos , Sensibilidad y Especificidad
12.
Mutat Res ; 306(1): 81-3, 1994 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-7512205

RESUMEN

The effects of herpes simplex virus type I (HSV-I) on SCE frequencies in human lymphocytes in vitro were investigated. SCE frequencies in controls (mean +/- 1SD 5.2 +/- 1.6) and in cells exposed to the virus for 3 and 6 h (mean +/- 1SD 5.3 +/- 1.6 and 5.8 +/- 1.6 respectively) were about the same. However, cells infected for 9 to 24 h showed a significant increase of SCE frequencies (p < 0.05).


Asunto(s)
Herpesvirus Humano 1/patogenicidad , Intercambio de Cromátides Hermanas , Células Cultivadas , Humanos , Linfocitos/ultraestructura
13.
Mikrobiyol Bul ; 25(3): 265-71, 1991 Jul.
Artículo en Turco | MEDLINE | ID: mdl-1762594

RESUMEN

In this study, effect of four broad spectrum antibiotics (sodium cefoperazone, sulbactam-ampicillin, mezlocillin, rifamycin) on primary antibody response. Therefore, sheep red blood cells were injected into total 25 rabbits in control and experiment groups. Hemolysin levels were titrated in serum specimens prepared from blood specimens taken before the experiment and taken three weeks after the last antigen injection. It was found that statistically significant in all the experiment groups rather than control (p less than 0.05).


Asunto(s)
Ampicilina/farmacología , Formación de Anticuerpos/efectos de los fármacos , Cefoperazona/farmacología , Mezlocilina/farmacología , Rifamicinas/farmacología , Sulbactam/farmacología , Animales , Quimioterapia Combinada/farmacología , Conejos
14.
Mikrobiyol Bul ; 24(2): 133-9, 1990 Apr.
Artículo en Turco | MEDLINE | ID: mdl-2089232

RESUMEN

In this study, antitoxin levels against tetanus were examined in the sera of 261 male and 139 female subjects (totally 400 subjects) in the age range from one day to 85 years. Tetanus antitoxin titres were determined by Pitzurra et all. passive hemagglutination technique using turkey red blood cells. In the age group of 6-15 years, antitoxin levels were significantly higher than those of other groups and above 30 years old group this levels significantly below than the other groups (p less than 0.05). All groups of female, except the group under 5 years of age, had lower antitoxin levels than those male and this difference was found significant statistically (p less than 0.05).


Asunto(s)
Antitoxina Tetánica/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Pruebas de Hemaglutinación , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Factores Sexuales
15.
Mikrobiyol Bul ; 22(3): 199-204, 1988.
Artículo en Turco | MEDLINE | ID: mdl-3252112

RESUMEN

The effect of blood on the activity of 7.5% povidine-iodine, 4% chlorhexidine gluconate, 10% benzalconium chloride, 1.5% chlorhexidine gluconate with cetrimide mixture, dust detergent and soap has been investigated. Two experimental methods have been applied. Using the first experimental method, the activity of antiseptics with an absence and presence of 25% blood in vitro has been investigated. It has been observed that povidone-iodine no germicidal activity at all whereas the activities of the other antiseptics decreased in varying raties. In the second experiment, the effect of blood has been investigated while the activity of antiseptics continued on the residuent flora of the hands. The changes brought about by blood was not found to statistically significant.


Asunto(s)
Antiinfecciosos Locales/farmacología , Bacterias/efectos de los fármacos , Sangre , Mano , Humanos , Piel/microbiología
16.
Mikrobiyol Bul ; 22(4): 303-7, 1988.
Artículo en Turco | MEDLINE | ID: mdl-3252121

RESUMEN

In the study, the antimicrobial activities of 7.5% povidone-iodine, 4% chlorhexidine gluconate, 1.5% chlorhexidine gluconate, 1.5% chlorhexidine gluconate with cetrimide mixture, 10% benzalconium chloride, dust detergent and soap as well as changes in activity in due course of time have been investigated. It has been observed that the effect of germicides on Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter cloacae and Candida strains increased in time. Soap had no germicidal effect. The difference between the of antiseptics on the residuent flora of the hands immediately and those two hours later was found to be statistically insignificant.


Asunto(s)
Antiinfecciosos Locales/farmacología , Bacterias/efectos de los fármacos , Candida/efectos de los fármacos
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