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1.
Hered Cancer Clin Pract ; 19(1): 25, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33926505

RESUMEN

BACKGROUND: Familial adenomatous polyposis (FAP) is an autosomal dominant condition that predisposes patients to colorectal cancer. FAP is the result of a loss of APC function due to germline pathogenic variants disrupting gene expression. Genotype-phenotype correlations are described for FAP. For example attenuated forms of the disease are associated with pathogenic variants at the 5' and 3' ends of APC whilst severe forms of the disease appear to be linked to variants occurring in the mutation cluster region (MCR) of the gene. Variants occurring in the MCR are phenotypically associated with hundreds to thousands of adenomas carpeting the colon and rectum and patients harbouring changes in this region have a high propensity to develop colorectal cancer. Not all patients who carry pathogenic variants in this region have severe disease which may be a result of environmental factors. Alternatively, phenotypic variation observed in these patients could be due to modifier genes that either promote or inhibit disease expression. Mouse models of FAP have provided several plausible candidate modifier genes, but very few of these have survived scrutiny. One such genetic modifier that appears to be associated with disease expression is CD36. We previously reported a weak association between a polymorphism in CD36 and a later age of disease onset on a relatively small FAP patient cohort. METHODS: In the current study, we enlarged the FAP cohort. 395 patients all carrying pathogenic variants in APC were tested against three CD36 Single Nucleotide Polymorphisms (SNP)s (rs1049673, rs1761667 rs1984112), to determine if any of them were associated with differences in the age of disease expression. RESULTS: Overall, there appeared to be a statistically significant difference in the age of disease onset between carriers of the variant rs1984112 and wildtype. Furthermore, test equality of survivor functions for each SNP and mutation group suggested an interaction in the Log Rank, Wilcoxon, and Tarone-Ware methods for rs1049673, rs1761667, and rs1984112, thereby supporting the notion that CD36 modifies disease expression. CONCLUSIONS: This study supports and strengthens our previous findings concerning CD36 and an association with disease onset in FAP, AFAP and FAP-MCR affected individuals. Knowledge about the role CD36 in adenoma development may provide greater insight into the development of colorectal cancer.

2.
BMC Microbiol ; 19(1): 33, 2019 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-30736731

RESUMEN

BACKGROUND: Lactobacillus mucosae DPC 6426 has previously demonstrated potentially cardio-protective properties, in the form of dyslipidaemia and hypercholesterolemia correction in an apolipoprotein-E deficient mouse model. This study aims to characterise the manner in which this microbe may modulate host bile pool composition and immune response, in the context of cardiovascular disease. Lactobacillus mucosae DPC 6426 was assessed for bile salt hydrolase activity and specificity. The microbe was compared against several other enteric strains of the same species, as well as a confirmed bile salt hydrolase-active strain, Lactobacillus reuteri APC 2587. RESULTS: Quantitative bile salt hydrolase assays revealed that enzymatic extracts from Lactobacillus reuteri APC 2587 and Lactobacillus mucosae DPC 6426 demonstrate the greatest activity in vitro. Bile acid profiling of porcine and murine bile following incubation with Lactobacillus mucosae DPC 6426 confirmed a preference for hydrolysis of glyco-conjugated bile acids. In addition, the purified exopolysaccharide and secretome of Lactobacillus mucosae DPC 6426 were investigated for immunomodulatory capabilities using RAW264.7 macrophages. Gene expression data revealed that both fractions stimulated increases in interleukin-6 and interleukin-10 gene transcription in the murine macrophages, while the entire secretome was necessary to increase CD206 transcription. Moreover, the exopolysaccharide elicited a dose-dependent increase in nitric oxide and interleukin-10 production from RAW264.7 macrophages, concurrent with increased tumour necrosis factor-α secretion at all doses. CONCLUSIONS: This study indicates that Lactobacillus mucosae DPC 6426 modulates both bile pool composition and immune system tone in a manner which may contribute significantly to the previously identified cardio-protective phenotype.


Asunto(s)
Amidohidrolasas/biosíntesis , Bilis/metabolismo , Inmunomodulación , Lactobacillus/enzimología , Lactobacillus/inmunología , Macrófagos/inmunología , Animales , Enfermedades Cardiovasculares/inmunología , Enfermedades Cardiovasculares/microbiología , Glicosiltransferasas/metabolismo , Hidrólisis , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Limosilactobacillus reuteri/enzimología , Lectinas Tipo C/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/microbiología , Receptor de Manosa , Lectinas de Unión a Manosa/metabolismo , Ratones , Óxido Nítrico/metabolismo , Polisacáridos Bacterianos/farmacología , Células RAW 264.7 , Receptores de Superficie Celular/metabolismo , Porcinos , Factor de Necrosis Tumoral alfa/metabolismo
3.
J Nutr ; 144(12): 1956-62, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25320181

RESUMEN

BACKGROUND: Probiotic bacteria have been associated with a reduction in cardiovascular disease risk, a leading cause of death and disability. OBJECTIVES: The aim of this study was to assess the impact of dietary administration of exopolysaccharide-producing probiotic Lactobacillus cultures on lipid metabolism and gut microbiota in apolipoprotein E (apoE)-deficient mice. METHODS: First, we examined lipid metabolism in response to dietary supplementation with recombinant ß-glucan-producing Lactobacillus paracasei National Food Biotechnology Centre (NFBC) 338 expressing the glycosyltransferase (Gtf) gene from Pediococcus parvulus 2.6 (GTF), and naturally exopolysaccharide-producing Lactobacillus mucosae Dairy Product Culture Collection (DPC) 6426 (DPC 6426) compared with the non-ß-glucan-producing isogenic control strain Lactobacillus paracasei NFBC 338 (PNZ) and placebo (15% wt:vol trehalose). Second, we examined the effects on the gut microbiota of dietary administration of DPC 6426 compared with placebo. Probiotic Lactobacillus strains at 1 × 10(9) colony-forming units/d per animal were administered to apoE(-/-) mice fed a high-fat (60% fat)/high-cholesterol (2% wt:wt) diet for 12 wk. At the end of the study, aortic plaque development and serum, liver, and fecal variables involved in lipid metabolism were analyzed, and culture-independent microbial analyses of cecal content were performed. RESULTS: Total cholesterol was reduced in serum (P < 0.001; ∼33-50%) and liver (P < 0.05; ∼30%) and serum triglyceride concentrations were reduced (P < 0.05; ∼15-25%) in mice supplemented with GTF or DPC 6426 compared with the PNZ or placebo group, respectively. In addition, dietary intervention with GTF led to increased amounts of fecal cholesterol excretion (P < 0.05) compared with all other groups. Compositional sequencing of the gut microbiota revealed a greater prevalence of Porphyromonadaceae (P = 0.001) and Prevotellaceae (P = 0.001) in the DPC 6426 group and lower proportions of Clostridiaceae (P < 0.05), Peptococcaceae (P < 0.001), and Staphylococcaceae (P < 0.01) compared with the placebo group. CONCLUSION: Ingestion of exopolysaccharide-producing lactobacilli resulted in seemingly favorable improvements in lipid metabolism, which were associated with changes in the gut microbiota of mice.


Asunto(s)
Colesterol/sangre , Glicosiltransferasas/metabolismo , Lactobacillus/metabolismo , Metabolismo de los Lípidos , Microbiota , Probióticos/administración & dosificación , Animales , Apolipoproteínas E/genética , Aterosclerosis/prevención & control , Dieta , Suplementos Dietéticos , Modelos Animales de Enfermedad , Heces/microbiología , Tracto Gastrointestinal/microbiología , Regulación Enzimológica de la Expresión Génica , Glicosiltransferasas/genética , Lactobacillus/genética , Hígado/metabolismo , Ratones , Ratones Noqueados , Pediococcus/enzimología , Triglicéridos/sangre , Molécula 1 de Adhesión Celular Vascular/sangre , beta-Glucanos/sangre
4.
Przegl Lek ; 66(10): 736-7, 2009.
Artículo en Polaco | MEDLINE | ID: mdl-20301925

RESUMEN

It is common knowledge that smoking badly influences people's health. Amount of toxic chemical substances delivered to the human organism is directly proportional to the number of smoked cigarettes. Tobacco smoking increases the number of ill people and accelerates death. The problem of nicotine addiction has both social and medical aspects. The aim of the work was to assess the tobacco smoking among patients hospitalized in the Gastroenterology Clinic in SPSK 4 in Lublin. We found that smoking prevalence in the investigated group considerably exceeds the average values for Polish population.


Asunto(s)
Unidades Hospitalarias/estadística & datos numéricos , Hepatopatías/epidemiología , Tabaquismo/epidemiología , Adulto , Comorbilidad , Femenino , Humanos , Masculino , Polonia/epidemiología , Prevalencia , Distribución por Sexo
5.
AJNR Am J Neuroradiol ; 39(5): 968-973, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29650780

RESUMEN

BACKGROUND AND PURPOSE: Vertebral hemangiomas are benign vascular lesions that are almost always incidentally found in the spine. Their classic typical hyperintense appearance on T1- and T2-weighted MR images is diagnostic. Unfortunately, not all hemangiomas have the typical appearance, and they can mimic metastases on routine MR imaging. These are generally referred to as atypical hemangiomas and can result in misdiagnosis and ultimately additional imaging, biopsy, and unnecessary costs. Our objective was to assess the utility of dynamic contrast-enhanced MR imaging perfusion in distinguishing vertebral atypical hemangiomas and malignant vertebral metastases. We hypothesized that permeability and vascular density will be increased in metastases compared with atypical hemangiomas. MATERIALS AND METHODS: Consecutive patients from 2011 to 2015 with confirmed diagnoses of atypical hemangiomas and spinal metastases from breast and lung carcinomas with available dynamic contrast-enhanced MR imaging were analyzed. Time-intensity curves were qualitatively compared among the groups. Perfusion parameters, plasma volume, and permeability constant were quantified using an extended Tofts 2-compartment pharmacokinetic model. Statistical significance was tested using the Mann-Whitney U test. RESULTS: Qualitative inspection of dynamic contrast-enhanced MR imaging time-intensity curves demonstrated differences in signal intensity and morphology between metastases and atypical hemangiomas. Quantitative analysis of plasma volume and permeability constant perfusion parameters showed significantly higher values in metastatic lesions compared with atypical hemangiomas (P < .001). CONCLUSIONS: Our data demonstrate that plasma volume and permeability constant perfusion parameters and qualitative inspection of contrast-enhancement curves can be used to differentiate atypical hemangiomas from vertebral metastatic lesions. This work highlights the benefits of adding perfusion maps to conventional sequences to improve diagnostic accuracy.


Asunto(s)
Hemangioma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Hemangioma/patología , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión , Neoplasias de la Columna Vertebral/secundario , Estadísticas no Paramétricas
6.
AJNR Am J Neuroradiol ; 38(11): 2210-2216, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28912284

RESUMEN

BACKGROUND AND PURPOSE: Chordomas notoriously demonstrate a paucity of changes following radiation therapy on conventional MR imaging. We hypothesized that dynamic contrast-enhanced MR perfusion imaging parameters of chordomas would change significantly following radiation therapy. MATERIALS AND METHODS: Eleven patients with pathology-proved chordoma who completed dynamic contrast-enhanced MR perfusion imaging pre- and postradiation therapy were enrolled. Quantitative tumor measurements were obtained by 2 attending neuroradiologists. ROIs were used to calculate vascular permeability and plasma volume and generate dynamic contrast-enhancement curves. Quantitative analysis was performed to determine mean and maximum plasma volume and vascular permeability values, while semiquantitative analysis on averaged concentration curves was used to determine the area under the curve. A Mann-Whitney U test at a significance level of P < .05 was used to assess differences of the above parameters between pre- and postradiation therapy. RESULTS: Plasma volume mean (pretreatment mean = 0.82; posttreatment mean = 0.42), plasma volume maximum (pretreatment mean = 3.56; posttreatment mean = 2.27), and vascular permeability mean (pretreatment mean = 0.046; posttreatment mean = 0.028) in the ROIs significantly decreased after radiation therapy (P < .05); this change thereby demonstrated the potential for assessing tumor response. Area under the curve values also demonstrated significant differences (P < .05). CONCLUSIONS: Plasma volume and vascular permeability decreased after radiation therapy, suggesting that these dynamic contrast-enhanced MR perfusion parameters may be useful for monitoring chordoma growth and response to radiation therapy. Additionally, the characteristic dynamic MR signal intensity-time curve of chordoma may provide a radiographic means of distinguishing chordoma from other spinal lesions.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/radioterapia , Cordoma/diagnóstico por imagen , Cordoma/radioterapia , Imagen por Resonancia Magnética/métodos , Imagen de Perfusión/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Microbiome ; 5(1): 30, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28285599

RESUMEN

BACKGROUND: There is strong evidence indicating that gut microbiota have the potential to modify, or be modified by the drugs and nutritional interventions that we rely upon. This study aims to characterize the compositional and functional effects of several nutritional, neutraceutical, and pharmaceutical cardiovascular disease interventions on the gut microbiome, through metagenomic and metabolomic approaches. Apolipoprotein-E-deficient mice were fed for 24 weeks either high-fat/cholesterol diet alone (control, HFC) or high-fat/cholesterol in conjunction with one of three dietary interventions, as follows: plant sterol ester (PSE), oat ß-glucan (OBG) and bile salt hydrolase-active Lactobacillus reuteri APC 2587 (BSH), or the drug atorvastatin (STAT). The gut microbiome composition was then investigated, in addition to the host fecal and serum metabolome. RESULTS: We observed major shifts in the composition of the gut microbiome of PSE mice, while OBG and BSH mice displayed more modest fluctuations, and STAT showed relatively few alterations. Interestingly, these compositional effects imparted by PSE were coupled with an increase in acetate and reduction in isovalerate (p < 0.05), while OBG promoted n-butyrate synthesis (p < 0.01). In addition, PSE significantly dampened the microbial production of the proatherogenic precursor compound, trimethylamine (p < 0.05), attenuated cholesterol accumulation, and nearly abolished atherogenesis in the model (p < 0.05). However, PSE supplementation produced the heaviest mice with the greatest degree of adiposity (p < 0.05). Finally, PSE, OBG, and STAT all appeared to have considerable impact on the host serum metabolome, including alterations in several acylcarnitines previously associated with a state of metabolic dysfunction (p < 0.05). CONCLUSIONS: We observed functional alterations in microbial and host-derived metabolites, which may have important implications for systemic metabolic health, suggesting that cardiovascular disease interventions may have a significant impact on the microbiome composition and functionality. This study indicates that the gut microbiome-modifying effects of novel therapeutics should be considered, in addition to the direct host effects.


Asunto(s)
Apolipoproteínas E/deficiencia , Heces/microbiología , Microbioma Gastrointestinal , Metaboloma , Acetatos/metabolismo , Animales , Aterosclerosis , Atorvastatina/administración & dosificación , Butiratos/metabolismo , Enfermedades Cardiovasculares/tratamiento farmacológico , Carnitina/análogos & derivados , Carnitina/sangre , Colesterol/metabolismo , Colesterol en la Dieta/administración & dosificación , Dieta Alta en Grasa , Suplementos Dietéticos , Hemiterpenos , Limosilactobacillus reuteri , Masculino , Ratones , Obesidad , Ácidos Pentanoicos/metabolismo , Probióticos , beta-Glucanos/administración & dosificación
8.
Ambio ; 45(5): 551-66, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26932602

RESUMEN

Sheep grazing is an important part of agriculture in the North Atlantic region, defined here as the Faroe Islands, Greenland, Iceland, Norway and Scotland. This process has played a key role in shaping the landscape and biodiversity of the region, sometimes with major environmental consequences, and has also been instrumental in the development of its rural economy and culture. In this review, we present results of the first interdisciplinary study taking a long-term perspective on sheep management, resource economy and the ecological impacts of sheep grazing, showing that sustainability boundaries are most likely to be exceeded in fragile environments where financial support is linked to the number of sheep produced. The sustainability of sheep grazing can be enhanced by a management regime that promotes grazing densities appropriate to the site and supported by area-based subsidy systems, thus minimizing environmental degradation, encouraging biodiversity and preserving the integrity of ecosystem processes.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Monitoreo del Ambiente/métodos , Herbivoria , Ovinos/crecimiento & desarrollo , Animales , Océano Atlántico , Conservación de los Recursos Naturales/economía , Monitoreo del Ambiente/economía , Población Rural
9.
Genome Announc ; 3(1)2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25593248

RESUMEN

Exopolysaccharide-synthesizing Lactobacillus mucosae DPC 6426 is a heterofermentative strain, which has demonstrated cholesterol-lowering properties in an animal model of lipid-driven atherosclerosis. The genome revealed a plethora of homologues linked to carbohydrate metabolism and mucin binding.

10.
FEBS Lett ; 240(1-2): 186-90, 1988 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-2461321

RESUMEN

Tachykinins of different classes (NK1, NK2, NK3) caused the concentration-dependent synthesis of IP3 in rat submandibular acinar cells with the potency rank order of NK1 greater than NK2 greater than NK3. Enhancement of IP3 was not affected by pertussis toxin treatment. The reverse rank order was found in the tachykinin inhibition of isoproterenol-induced cAMP synthesis and this inhibition was abolished by pertussis toxin, an inactivator of the adenylate cyclase Gi regulatory protein. It is suggested that different tachykinin receptor subtypes are preferentially coupled to phospholipase C or adenylate cyclase by separate G regulatory proteins in rat submandibular acinar cells.


Asunto(s)
AMP Cíclico/fisiología , Fosfatidilinositoles/fisiología , Receptores de Neurotransmisores/metabolismo , Glándula Submandibular/fisiología , Taquicininas/fisiología , Toxina de Adenilato Ciclasa , Animales , Técnicas In Vitro , Inositol 1,4,5-Trifosfato , Fosfatos de Inositol/metabolismo , Isoproterenol/farmacología , Toxina del Pertussis , Ratas , Receptores de Taquicininas , Sustancia P/farmacología , Factores de Virulencia de Bordetella/farmacología
11.
J Med Chem ; 41(12): 2146-63, 1998 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-9622556

RESUMEN

The previously reported oxytocin antagonist L-371,257 (2) has been modified at its acetylpiperidine terminus to incorporate various pyridine N-oxide groups. This modification has led to the identification of compounds with improved pharmacokinetics and excellent oral bioavailability. The pyridine N-oxide series is exemplified by L-372,662 (30), which possessed good potency in vitro (Ki = 4.1 nM, cloned human oxytocin receptor) and in vivo (intravenous AD50 = 0.71 mg/kg in the rat), excellent oral bioavailability (90% in the rat, 96% in the dog), good aqueous solubility (>8.5 mg/mL at pH 5.2) which should facilitate formulation for iv administration, and excellent selectivity against the human arginine vasopressin receptors. Incorporation of a 5-fluoro substituent on the central benzoyl ring of this class of oxytocin antagonists enhanced in vitro and in vivo potency but was detrimental to the pharmacokinetic profiles of these compounds. Although lipophilic substitution around the pyridine ring of compound 30 gave higher affinity in vitro, such substituents were a metabolic liability and caused shortfalls in vivo. Two approaches to prevent this metabolism, addition of a cyclic constraint and incorporation of trifluoromethyl groups, were examined. The former approach was ineffective because of metabolic hydroxylation on the constrained ring system, whereas the latter showed improvement in plasma pharmacokinetics in some cases.


Asunto(s)
Oxazinas , Piridinas , Receptores de Oxitocina/antagonistas & inhibidores , Administración Oral , Animales , Disponibilidad Biológica , Línea Celular , Cromatografía Líquida de Alta Presión , Perros , Femenino , Humanos , Riñón/citología , Riñón/embriología , Riñón/metabolismo , Hígado/metabolismo , Masculino , Espectrometría de Masas , Oxazinas/síntesis química , Oxazinas/metabolismo , Oxazinas/farmacocinética , Oxazinas/farmacología , Embarazo , Piridinas/síntesis química , Piridinas/metabolismo , Piridinas/farmacocinética , Piridinas/farmacología , Ratas , Receptores de Oxitocina/metabolismo , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/metabolismo , Espectrofotometría Ultravioleta , Contracción Uterina/efectos de los fármacos , Útero/efectos de los fármacos , Útero/fisiología
12.
Bone Marrow Transplant ; 26(8): 917-9, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11081396

RESUMEN

Epilepsia partialis continua (EPC) is a condition defined by prolonged focal myoclonus. Often resistant to therapy, EPC in children is frequently present in Rasmussen encephalitis, a form of chronic encephalitis of uncertain etiology. We discuss a child who developed bilateral EPC 5 months after a bone marrow transplant. Neuroimaging studies showed signal abnormalities on both sensory-motor areas. An extensive search failed to reveal the etiology of the disorder, but treatment with a broad-spectrum anti-viral agent was associated with resolution of the process. An unidentified infectious agent may be responsible for an encephalitis of the motor strip in immunosuppressed patients.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Encefalitis/etiología , Epilepsia Parcial Continua/etiología , Niño , Encefalitis/terapia , Epilepsia Parcial Continua/terapia , Humanos , Masculino
13.
Ann Thorac Surg ; 65(6): 1656-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9647076

RESUMEN

BACKGROUND: Stroke complicates cardiac surgical procedures in a substantial number of patients. The mechanism of stroke is predominantly embolic, although hypoperfusion may play a role. The aim of this study was to determine whether radiologic appearances in this population were consistent with an embolic cause. METHODS: We reviewed computed tomographic scans and medical records in 24 patients who suffered stroke after cardiac operation. Stroke was evident at 24 hours in 19 patients (79%). Infarcts were multiple in 16 and single in 3 patients (group 1). The remaining 5 patients suffered stroke beyond 24 hours and had single infarcts on computed tomographic scan (group 2). RESULTS: In group 1, 15 patients (79%) had bilateral cerebellar infarcts, 4 (74%) had posterior cerebral artery infarcts, 10 (53%) had posterior watershed infarcts, and 11 patients (58%) had middle cerebral artery branch infarcts. The mean number of vascular territories involved was 5.1 (range, 1 to 10). Mobile atheromatous plaque was present in the ascending aorta or arch in 5 of 9 patients (56%) in group 1. In group 2, stroke occurred in close association with atrial or ventricular fibrillation in 3 of 5 patients (60%). CONCLUSIONS: In patients with radiologic evidence of infarction, perioperative strokes after cardiac operation are typically multiple, and involve the posterior parts of the brain, consistent with atheroembolization. Delayed strokes may be attributable to cardiogenic embolism.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Infarto Cerebral/etiología , Trastornos Cerebrovasculares/etiología , Anciano , Anciano de 80 o más Años , Aorta/diagnóstico por imagen , Aorta Torácica/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/etiología , Arteriosclerosis/diagnóstico por imagen , Arteriosclerosis/etiología , Fibrilación Atrial/etiología , Cerebelo/irrigación sanguínea , Arterias Cerebrales/diagnóstico por imagen , Infarto Cerebral/diagnóstico por imagen , Circulación Cerebrovascular , Trastornos Cerebrovasculares/diagnóstico por imagen , Ecocardiografía Transesofágica , Embolia/diagnóstico por imagen , Embolia/etiología , Femenino , Humanos , Infarto/diagnóstico por imagen , Infarto/etiología , Embolia y Trombosis Intracraneal/diagnóstico por imagen , Embolia y Trombosis Intracraneal/etiología , Complicaciones Intraoperatorias/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Fibrilación Ventricular/etiología
14.
Eur J Pharmacol ; 188(2-3): 171-4, 1990 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-2156713

RESUMEN

The receptor subtypes involved in muscarinic-induced phosphoinositide hydrolysis and adenylate cyclase inhibition in rat submandibular acinar cells were characterized by comparing the inhibitory potencies of four muscarinic antagonists on the two signal transduction responses. Carbachol-induced phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis was inhibited by all antagonists with a potency rank order of 4-diphenylacetoxy-N-methyl piperidine methobromide (4-DAMP) = atropine much greater than pirenzepine much greater than AF-DX 116 (P less than 0.01). The same rank order was observed in antagonist-reversal of the reduction of cAMP caused by carbachol in the model. These findings suggest that muscarinic effects are mediated by M3 receptors in both the phosphoinositide and adenylate cyclase pathways in the submandibular gland.


Asunto(s)
Parasimpatolíticos/farmacología , Receptores Muscarínicos/metabolismo , Transducción de Señal/efectos de los fármacos , Glándula Submandibular/metabolismo , Animales , Atropina/farmacología , Carbacol/farmacología , AMP Cíclico/metabolismo , Fosfatidilinositol 4,5-Difosfato , Fosfatidilinositoles/farmacología , Piperidinas/farmacología , Pirenzepina/análogos & derivados , Pirenzepina/farmacología , Ratas , Glándula Submandibular/efectos de los fármacos
15.
Eur J Pharmacol ; 196(3): 233-7, 1991 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-1893911

RESUMEN

From a series of potent cyclic hexapeptide oxytocin (OT) antagonists, a compound that exhibited significant bradykinin (BK) agonist activity was identified. L-366,811 (cyclo[L-proline-D-tryptophan-L-isoleucine-D-pipecolic acid-L-piperazine-2-carboxylic acid-N-Me-D-phenylalanine]) stimulated phosphatidylinositol (PI) turnover in rat uterine slices in vitro (approximately EC50, 2 microM) with a maximal effect (15-fold increase over basal) greater than that obtained for either BK or OT. L-366,811 also elicited dose-related contractions of the isolated rat uterus, producing measurable effects at 100 nM. Several other equally potent OT antagonists from the cyclic hexapeptide structural class were either less potent or inactive as activators of uterine PI turnover or contractility. The stimulatory effects of L-366,811 on uterine PI turnover and contractions were blocked by BK antagonists but not by an arginine vasopressin (AVP)/OT antagonist. In radioligand binding studies, L-366,811 exhibited moderate affinity (IC50, 360 nM) for the [3H]BK binding site in rat uterus, consistent with its potency in the functional models. These results indicate that L-366,811 exhibits BK agonist activity in rat uterus in vitro.


Asunto(s)
Bradiquinina/fisiología , Oxitocina/antagonistas & inhibidores , Péptidos Cíclicos/farmacología , Útero/efectos de los fármacos , Animales , Bradiquinina/metabolismo , Femenino , Fosfatos de Inositol/metabolismo , Ratas , Ratas Endogámicas , Tritio , Contracción Uterina/efectos de los fármacos , Útero/metabolismo
16.
Life Sci ; 44(15): 1027-35, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2538696

RESUMEN

The involvement of G regulatory proteins in muscarinic receptor signal transduction was examined in electrically permeabilized rat submandibular acinar cells. The guanine nucleotide analog, GTP gamma S, caused the dose dependent hydrolysis of membrane phosphatidylinositol 4,5-bisphosphate to release IP3. This response was insensitive to pertussis toxin treatment and was duplicated by NaF but not by GDP beta S. Enhanced IP3 synthesis was observed with a combination of GTP gamma S and carbachol. Exogenous IP3, as well as carbachol and GTP gamma S, provoked the release of sequestered 45Ca2+ from non-mitochondrial stores. In intact cells, carbachol significantly reduced the level of cyclic AMP induced by the beta-adrenergic agonist, isoproterenol, to 69% of its normal value. Pertussis toxin abolished this inhibitory action of carbachol on cyclic nucleotide levels. These results suggest that muscarinic receptors are coupled to two separate G regulatory proteins in submandibular mucous acini-the pertussis toxin-insensitive Gp of the phosphoinositide transduction pathway associated with elevated cytosolic calcium levels, and the pertussis toxin-sensitive Gi inhibitory protein of the adenylate cyclase complex.


Asunto(s)
Proteínas de Unión al GTP/fisiología , Receptores Muscarínicos/fisiología , Transducción de Señal , Glándula Submandibular/fisiología , Toxina de Adenilato Ciclasa , Animales , Calcio/metabolismo , Carbacol/farmacología , Guanosina 5'-O-(3-Tiotrifosfato) , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/farmacología , Técnicas In Vitro , Inositol 1,4,5-Trifosfato , Fosfatos de Inositol/farmacología , Isoproterenol/farmacología , Cinética , Membrana Mucosa/citología , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/fisiología , Toxina del Pertussis , Fosfatidilinositoles/fisiología , Ratas , Transducción de Señal/efectos de los fármacos , Glándula Submandibular/citología , Glándula Submandibular/efectos de los fármacos , Tionucleótidos/farmacología , Factores de Virulencia de Bordetella/farmacología
17.
Life Sci ; 58(14): 1149-57, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8614266

RESUMEN

L-744,453 ((+/-)3-[4-(1-carboxy-1-(3,4-methylenedioxyphenyl)methoxy)-3,5-diprop ylphenyl methyl]-3H-imidazo[4,5-c]pyridine) is an endothelin (ET) receptor antagonist from a new structural class, the dipropyl-alpha-phenoxyphenylacetic acid derivatives. L-744,453 competitively and reversibly inhibits [125I]-ET-1 binding to Chinese Hamster Ovary cells expressing cloned human ET receptors (K(i)s: hET(A)=4.3 nM; hET(B)=232 nM), and is selective for endothelin receptors compared to other peptide receptors. It is an antagonist of ET-1 stimulated phosphatidyl inositol hydrolysis in rat uterine slices (IC50=220 nM) and exhibits no agonist activity. This compound also inhibits ET-1 stimulated contraction of rat aortic rings with a K(b) value of 50 nM. L-744,453 protects against ET-1 induced lethality in mice after i.v. (AD50=13 mg/kg i.v.) or oral administration. This compound also antagonizes ET-1 induced increases in diastolic blood pressure in conscious normotensive rats (AD50=0.67 mg/kg i.v.) and anesthetized ferrets (AD50=1.6 mg/kg i.v.). L-744,453 is a potent, selective, orally active endothelin antagonist which may be useful in elucidating the role of endothelin in normal and pathophysiological states.


Asunto(s)
Dioxoles/farmacología , Antagonistas de los Receptores de Endotelina , Imidazoles/farmacología , Animales , Disponibilidad Biológica , Presión Sanguínea/efectos de los fármacos , Células CHO/efectos de los fármacos , Células CHO/metabolismo , Cricetinae , Dioxoles/metabolismo , Dioxoles/toxicidad , Perros , Endotelinas/antagonistas & inhibidores , Endotelinas/metabolismo , Endotelinas/farmacología , Femenino , Hurones , Humanos , Hidrólisis , Imidazoles/metabolismo , Imidazoles/toxicidad , Técnicas In Vitro , Radioisótopos de Yodo , Cinética , Masculino , Ratones , Contracción Muscular/efectos de los fármacos , Fosfatidilinositoles/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Endotelina/metabolismo , Relación Estructura-Actividad
18.
Pediatr Neurol ; 20(3): 241-3, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10207937

RESUMEN

The association of an acute reversible encephalopathy with transient occipital lobe abnormalities on imaging studies is well known. This condition has been called reversible posterior leukoencephalopathy syndrome. The clinical presentation usually includes seizures, headache, altered mental status, and blindness, often associated with hypertension and immunosuppressants. The authors discuss a two-year-old male with Down syndrome who presented 2 months after allogeneic bone marrow transplantation with severe oculogyric crisis, without other complaints. The patient was being treated for hypertension and was receiving cyclosporine for prophylaxis of graft-vs-host disease. A computed tomography scan of the head revealed marked bilateral lucencies mainly involving the white matter of the occipital lobes, with a few foci of punctate hemorrhage. The condition improved when cyclosporine was discontinued, but an area of leukomalacia was identified on follow-up magnetic resonance imaging. To the authors' knowledge, oculogyric crisis as a presentation of reversible posterior leukoencephalopathy has not been previously described. Recognizing this association is important, because patients receiving cyclosporine are often receiving other medications that can potentially cause dystonic eye movements, possibly leading to a delay in diagnosis and treatment, which can result in an irreversible neurologic deficit.


Asunto(s)
Encefalopatías/diagnóstico , Encefalopatías/etiología , Ciclosporina/efectos adversos , Hipertensión Maligna/complicaciones , Lóbulo Occipital/anomalías , Trastornos de la Motilidad Ocular/etiología , Trasplante de Médula Ósea , Preescolar , Cromosomas Humanos Par 7 , Progresión de la Enfermedad , Humanos , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/terapia , Imagen por Resonancia Magnética , Masculino , Monosomía , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/terapia , Lóbulo Occipital/patología , Síndrome , Tomografía Computarizada por Rayos X
19.
Spine (Phila Pa 1976) ; 25(17): 2240-9,discussion 250, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10973409

RESUMEN

STUDY DESIGN: Retrospective review of prospectively maintained institutional spine database. OBJECTIVES: To assess the pain, neurologic, and functional outcome of patients with metastatic spinal cord compression using a posterolateral transpedicular approach with circumferential fusion. SUMMARY OF BACKGROUND DATA: Patients with spinal metastases often have patterns of disease requiring both an anterior and posterior surgical decompression and spinal fusion. For patients whose concurrent illness or previous surgery makes an anterior approach difficult, a posterior transpedicular approach was used to resect the involved vertebral bodies, posterior elements, and epidural tumor. This approach provides exposure sufficient to decompress and instrument the anterior and posterior columns. METHODS: During the past 15 months, 25 patients were operated on using a posterolateral transpedicular approach. The primary indications for surgery were back pain (15 patients) and neurologic progression (10 patients). All patients had vertebral body disease, and 21 patients had high-grade spinal cord compression from epidural disease as assessed by magnetic resonance imaging. Seven patients underwent preoperative embolization for vascular tumors. In each patient, the anterior column was reconstructed with polymethyl methacrylate and Steinmann pins and the posterior column with long segmental fixation. RESULTS: All patients achieved immediate stability. Pain relief was significant in all 23 patients who had had moderate or severe pain. Neurologic symptoms were stable or improved in 23 patients. One patient with an acutely evolving myelopathy was immediately worse after surgery, and one patient had a delayed neurologic worsening, progressing to paraplegia. CONCLUSIONS: The posterolateral transpedicular approach provides a wide surgical exposure to decompress and instrument the anterior and posterior spine. This technique avoids the morbidity associated with anterior approaches and provides immediate stability. Vascular tumors may be removed safely after embolization. Patients can be mobilized early after surgery.


Asunto(s)
Espacio Epidural/cirugía , Ortopedia/métodos , Dolor/cirugía , Cuidados Paliativos/métodos , Fusión Vertebral/métodos , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/cirugía , Columna Vertebral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Espacio Epidural/patología , Espacio Epidural/fisiopatología , Femenino , Humanos , Tiempo de Internación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dolor/etiología , Dolor/fisiopatología , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/complicaciones , Columna Vertebral/patología , Columna Vertebral/fisiopatología , Resultado del Tratamiento
20.
Adv Exp Med Biol ; 395: 601-12, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8714024

RESUMEN

From a targeted screening effort and medicinal chemistry program, L-368,899 was selected as the first orally-active oxytocin (OT) antagonist to enter clinical trials. In animal studies, L-368,899 was shown to be a potent and selective OT antagonist and was orally bioavailable in rats, dogs and chimpanzees. L-368,899 was further shown to be a potent OT antagonist in pregnant rhesus and to inhibit spontaneous nocturnal uterine contractions. In Phase I human studies, L-368,899 was generally well-tolerated given intravenously and showed significant plasma levels after oral administration. In addition, L-368,899 blocked OT-stimulated uterine activity in postpartum women with a potency similar to that in the pregnant rhesus monkey. More recently, another structural series has been pursued, represented by L-371,257 [1-(1-(4-(N-acetyl-4-piperidinyloxy)-2-methoxybenzoyl)pip eridin-4-yl)- 1,2-dihydro-4(H)-3,1-benzoxazin-2-one]. L-371,257 exhibits high affinity (Ki, 4.6 nM) for human uterine OT receptors with high selectivity vs. human vasopressin receptors. In rat tissues in vitro, L-371,257 is a potent and competitive OT antagonist (pA2, 8.4) and, in vivo, blocks OT-stimulated uterine activity given both i.v. and intraduodenally. L-371,257 highlights the promise of this novel structural class.


Asunto(s)
Antagonistas de Hormonas/uso terapéutico , Trabajo de Parto Prematuro/tratamiento farmacológico , Oxitocina/antagonistas & inhibidores , Tocolíticos/uso terapéutico , Animales , Benzoxazinas , Canfanos/administración & dosificación , Canfanos/química , Canfanos/uso terapéutico , Perros , Femenino , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/química , Humanos , Técnicas In Vitro , Macaca mulatta , Estructura Molecular , Trabajo de Parto Prematuro/fisiopatología , Oxazinas/química , Oxazinas/uso terapéutico , Pan troglodytes , Piperazinas/administración & dosificación , Piperazinas/química , Piperazinas/uso terapéutico , Piperidinas/química , Piperidinas/uso terapéutico , Embarazo , Ratas , Tocolíticos/administración & dosificación , Tocolíticos/química , Contracción Uterina/efectos de los fármacos
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