Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 80
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
Hered Cancer Clin Pract ; 19(1): 25, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33926505

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-30736731

RESUMO

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.


Assuntos
Amidoidrolases/biossíntese , Bile/metabolismo , Imunomodulação , Lactobacillus/enzimologia , Lactobacillus/imunologia , Macrófagos/imunologia , Animais , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/microbiologia , Glicosiltransferases/metabolismo , Hidrólise , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Limosilactobacillus reuteri/enzimologia , Lectinas Tipo C/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Polissacarídeos Bacterianos/farmacologia , Células RAW 264.7 , Receptores de Superfície Celular/metabolismo , Suínos , Fator de Necrose Tumoral alfa/metabolismo
3.
J Nutr ; 144(12): 1956-62, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25320181

RESUMO

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.


Assuntos
Colesterol/sangue , Glicosiltransferases/metabolismo , Lactobacillus/metabolismo , Metabolismo dos Lipídeos , Microbiota , Probióticos/administração & dosagem , Animais , Apolipoproteínas E/genética , Aterosclerose/prevenção & controle , Dieta , Suplementos Nutricionais , Modelos Animais de Doenças , Fezes/microbiologia , Trato Gastrointestinal/microbiologia , Regulação Enzimológica da Expressão Gênica , Glicosiltransferases/genética , Lactobacillus/genética , Fígado/metabolismo , Camundongos , Camundongos Knockout , Pediococcus/enzimologia , Triglicerídeos/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , beta-Glucanas/sangue
4.
Przegl Lek ; 66(10): 736-7, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-20301925

RESUMO

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.


Assuntos
Unidades Hospitalares/estatística & dados numéricos , Hepatopatias/epidemiologia , Tabagismo/epidemiologia , Adulto , Comorbidade , Feminino , Humanos , Masculino , Polônia/epidemiologia , Prevalência , Distribuição por Sexo
5.
AJNR Am J Neuroradiol ; 39(5): 968-973, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29650780

RESUMO

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.


Assuntos
Hemangioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Hemangioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão , Neoplasias da Coluna Vertebral/secundário , Estatísticas não Paramétricas
6.
AJNR Am J Neuroradiol ; 38(11): 2210-2216, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28912284

RESUMO

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.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/radioterapia , Cordoma/diagnóstico por imagem , Cordoma/radioterapia , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Microbiome ; 5(1): 30, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28285599

RESUMO

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.


Assuntos
Apolipoproteínas E/deficiência , Fezes/microbiologia , Microbioma Gastrointestinal , Metaboloma , Acetatos/metabolismo , Animais , Aterosclerose , Atorvastatina/administração & dosagem , Butiratos/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Carnitina/análogos & derivados , Carnitina/sangue , Colesterol/metabolismo , Colesterol na Dieta/administração & dosagem , Dieta Hiperlipídica , Suplementos Nutricionais , Hemiterpenos , Limosilactobacillus reuteri , Masculino , Camundongos , Obesidade , Ácidos Pentanoicos/metabolismo , Probióticos , beta-Glucanas/administração & dosagem
8.
Ambio ; 45(5): 551-66, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26932602

RESUMO

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.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Herbivoria , Ovinos/crescimento & desenvolvimento , Animais , Oceano Atlântico , Conservação dos Recursos Naturais/economia , Monitoramento Ambiental/economia , População Rural
9.
Genome Announc ; 3(1)2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25593248

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-2461321

RESUMO

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.


Assuntos
AMP Cíclico/fisiologia , Fosfatidilinositóis/fisiologia , Receptores de Neurotransmissores/metabolismo , Glândula Submandibular/fisiologia , Taquicininas/fisiologia , Toxina Adenilato Ciclase , Animais , Técnicas In Vitro , Inositol 1,4,5-Trifosfato , Fosfatos de Inositol/metabolismo , Isoproterenol/farmacologia , Toxina Pertussis , Ratos , Receptores de Taquicininas , Substância P/farmacologia , Fatores de Virulência de Bordetella/farmacologia
11.
J Med Chem ; 41(12): 2146-63, 1998 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-9622556

RESUMO

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.


Assuntos
Oxazinas , Piridinas , Receptores de Ocitocina/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Cães , Feminino , Humanos , Rim/citologia , Rim/embriologia , Rim/metabolismo , Fígado/metabolismo , Masculino , Espectrometria de Massas , Oxazinas/síntese química , Oxazinas/metabolismo , Oxazinas/farmacocinética , Oxazinas/farmacologia , Gravidez , Piridinas/síntese química , Piridinas/metabolismo , Piridinas/farmacocinética , Piridinas/farmacologia , Ratos , Receptores de Ocitocina/metabolismo , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Espectrofotometria Ultravioleta , Contração Uterina/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/fisiologia
12.
Bone Marrow Transplant ; 26(8): 917-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11081396

RESUMO

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.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Encefalite/etiologia , Epilepsia Parcial Contínua/etiologia , Criança , Encefalite/terapia , Epilepsia Parcial Contínua/terapia , Humanos , Masculino
13.
Ann Thorac Surg ; 65(6): 1656-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9647076

RESUMO

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.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Infarto Cerebral/etiologia , Transtornos Cerebrovasculares/etiologia , Idoso , Idoso de 80 Anos ou mais , Aorta/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etiologia , Arteriosclerose/diagnóstico por imagem , Arteriosclerose/etiologia , Fibrilação Atrial/etiologia , Cerebelo/irrigação sanguínea , Artérias Cerebrais/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Transtornos Cerebrovasculares/diagnóstico por imagem , Ecocardiografia Transesofagiana , Embolia/diagnóstico por imagem , Embolia/etiologia , Feminino , Humanos , Infarto/diagnóstico por imagem , Infarto/etiologia , Embolia e Trombose Intracraniana/diagnóstico por imagem , Embolia e Trombose Intracraniana/etiologia , Complicações Intraoperatórias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Fibrilação Ventricular/etiologia
14.
Eur J Pharmacol ; 188(2-3): 171-4, 1990 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-2156713

RESUMO

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.


Assuntos
Parassimpatolíticos/farmacologia , Receptores Muscarínicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Glândula Submandibular/metabolismo , Animais , Atropina/farmacologia , Carbacol/farmacologia , AMP Cíclico/metabolismo , Fosfatidilinositol 4,5-Difosfato , Fosfatidilinositóis/farmacologia , Piperidinas/farmacologia , Pirenzepina/análogos & derivados , Pirenzepina/farmacologia , Ratos , Glândula Submandibular/efeitos dos fármacos
15.
Eur J Pharmacol ; 196(3): 233-7, 1991 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-1893911

RESUMO

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.


Assuntos
Bradicinina/fisiologia , Ocitocina/antagonistas & inibidores , Peptídeos Cíclicos/farmacologia , Útero/efeitos dos fármacos , Animais , Bradicinina/metabolismo , Feminino , Fosfatos de Inositol/metabolismo , Ratos , Ratos Endogâmicos , Trítio , Contração Uterina/efeitos dos fármacos , Útero/metabolismo
16.
Life Sci ; 44(15): 1027-35, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2538696

RESUMO

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.


Assuntos
Proteínas de Ligação ao GTP/fisiologia , Receptores Muscarínicos/fisiologia , Transdução de Sinais , Glândula Submandibular/fisiologia , Toxina Adenilato Ciclase , Animais , Cálcio/metabolismo , Carbacol/farmacologia , Guanosina 5'-O-(3-Tiotrifosfato) , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/farmacologia , Técnicas In Vitro , Inositol 1,4,5-Trifosfato , Fosfatos de Inositol/farmacologia , Isoproterenol/farmacologia , Cinética , Mucosa/citologia , Mucosa/efeitos dos fármacos , Mucosa/fisiologia , Toxina Pertussis , Fosfatidilinositóis/fisiologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Glândula Submandibular/citologia , Glândula Submandibular/efeitos dos fármacos , Tionucleotídeos/farmacologia , Fatores de Virulência de Bordetella/farmacologia
17.
Life Sci ; 58(14): 1149-57, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8614266

RESUMO

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.


Assuntos
Dioxóis/farmacologia , Antagonistas dos Receptores de Endotelina , Imidazóis/farmacologia , Animais , Disponibilidade Biológica , Pressão Sanguínea/efeitos dos fármacos , Células CHO/efeitos dos fármacos , Células CHO/metabolismo , Cricetinae , Dioxóis/metabolismo , Dioxóis/toxicidade , Cães , Endotelinas/antagonistas & inibidores , Endotelinas/metabolismo , Endotelinas/farmacologia , Feminino , Furões , Humanos , Hidrólise , Imidazóis/metabolismo , Imidazóis/toxicidade , Técnicas In Vitro , Radioisótopos do Iodo , Cinética , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Fosfatidilinositóis/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Endotelina/metabolismo , Relação Estrutura-Atividade
18.
Pediatr Neurol ; 20(3): 241-3, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10207937

RESUMO

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.


Assuntos
Encefalopatias/diagnóstico , Encefalopatias/etiologia , Ciclosporina/efeitos adversos , Hipertensão Maligna/complicações , Lobo Occipital/anormalidades , Transtornos da Motilidade Ocular/etiologia , Transplante de Medula Óssea , Pré-Escolar , Cromossomos Humanos Par 7 , Progressão da Doença , Humanos , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/terapia , Imageamento por Ressonância Magnética , Masculino , Monossomia , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/terapia , Lobo Occipital/patologia , Síndrome , Tomografia Computadorizada por Raios X
19.
Spine (Phila Pa 1976) ; 25(17): 2240-9,discussion 250, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10973409

RESUMO

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.


Assuntos
Espaço Epidural/cirurgia , Ortopedia/métodos , Dor/cirurgia , Cuidados Paliativos/métodos , Fusão Vertebral/métodos , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Espaço Epidural/patologia , Espaço Epidural/fisiopatologia , Feminino , Humanos , Tempo de Internação , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Dor/fisiopatologia , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/complicações , Coluna Vertebral/patologia , Coluna Vertebral/fisiopatologia , Resultado do Tratamento
20.
Adv Exp Med Biol ; 395: 601-12, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8714024

RESUMO

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.


Assuntos
Antagonistas de Hormônios/uso terapêutico , Trabalho de Parto Prematuro/tratamento farmacológico , Ocitocina/antagonistas & inibidores , Tocolíticos/uso terapêutico , Animais , Benzoxazinas , Canfanos/administração & dosagem , Canfanos/química , Canfanos/uso terapêutico , Cães , Feminino , Antagonistas de Hormônios/administração & dosagem , Antagonistas de Hormônios/química , Humanos , Técnicas In Vitro , Macaca mulatta , Estrutura Molecular , Trabalho de Parto Prematuro/fisiopatologia , Oxazinas/química , Oxazinas/uso terapêutico , Pan troglodytes , Piperazinas/administração & dosagem , Piperazinas/química , Piperazinas/uso terapêutico , Piperidinas/química , Piperidinas/uso terapêutico , Gravidez , Ratos , Tocolíticos/administração & dosagem , Tocolíticos/química , Contração Uterina/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA