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1.
Rev Gastroenterol Mex (Engl Ed) ; 89(3): 404-417, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39033039

RESUMO

Acute liver failure is a rare but serious syndrome, with an incidence of approximately 2,000 to 3,000 cases per year in North America. Its pathophysiology and clinical course vary, depending on the cause of the primary liver injury, and can lead to high morbidity and mortality or the need for liver transplantation, despite available therapies. This syndrome involves excessive activation of the immune system, with damage in other organs, contributing to its high mortality rate. The most accepted definition includes liver injury with hepatic encephalopathy and coagulopathy within the past 26 weeks in a patient with no previous liver disease. The main causes are paracetamol poisoning, viral hepatitis, and drug-induced liver injury, among others. Identifying the cause is crucial, given that it influences prognosis and treatment. Survival has improved with supportive measures, intensive therapy, complication prevention, and the use of medications, such as N-acetylcysteine. Liver transplantation is a curative option for nonresponders to medical treatment, but adequate evaluation of transplantation timing is vital for improving results. Factors such as patient age, underlying cause, and severity of organ failure influence the post-transplant outcomes and survival.


Assuntos
Falência Hepática Aguda , Humanos , Falência Hepática Aguda/terapia , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/diagnóstico , Prognóstico , Transplante de Fígado
2.
Nanoscale Adv ; 3(17): 4926-4939, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34485816

RESUMO

Access to nanofabrication strategies for crafting three-dimensional plasmonic structures is limited. In this work, a fabrication strategy to produce 3D plasmonic hollow nanopillars (HNPs) using Talbot lithography and I-line photolithography is introduced. This method is named subtractive hybrid lithography (SHL), and permits intermixed usage of nano-and-macroscale patterns. Sputter-redeposition of gold (Au) on the SHL resist pattern yields large areas of dense periodic Au-HNPs. These Au-HNPs are arranged in a square unit cell with a 250 nm pitch. The carefully controlled fabrication process resulted in Au-HNPs with nanoscale dimensions over the Au-HNP dimensions such as an 80 ± 2 nm thick solid base with a 133 ± 4 nm diameter, and a 170 ± 10 nm high nano-rim with a 14 ± 3 nm sidewall rim-thickness. The plasmonic optical response is assessed with FDTD-modeling and reveals that the highest field enhancement is at the top of the hollow nanopillar rim. The modeled field enhancement factor (EF) is compared to the experimental analytical field enhancement factor, which shows to pair up with ca. 103 < EF < 104 and ca. 103 < EF < 105 for excitation wavelengths of 633 and 785 nm. From a broader perspective, our results can stimulate the use of Au-HNPs in the fields of plasmonic sensors and spectroscopy.

3.
Expert Rev Neurother ; 20(5): 439-448, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32303136

RESUMO

Introduction: Neuroinflammation has been proposed as a common factor and one of the main inducers of neuronal degeneration. Galectins are a group of ß-galactoside-binding lectins, that play an important role in the immune response, adhesion, proliferation, differentiation, migration and cell growth. Up to 15 members of the galectin's family have been identified; however, the expression of galectin-1 and galectin-3 has been considered a key factor in neuronal regeneration and modulation of the inflammatory response. Galectin-1 is necessary to stimulate the secretion of neurotrophic factors in astrocytes and promoting neuronal regeneration. In contrast, galectin-3 fosters the proliferation of microglial cells and modulates cellular apoptosis, therefore these proteins are considered a useful alternative for the treatment of degenerative diseases.Areas covered: This review describes the roles of galectin-1 and galectin-3 in the modulation of neuroinflammation and their potential as therapeutic targets in the treatment for neurodegenerative diseases.Expert opinion: Although data in the literature vary, the effects of galectin-1 and galectin-3 on the activation and modulation of astrocytes and microglia has been described. Due to its anti-inflammatory effects, galectin-1 is proposed as a molecule with therapeutic potential, whereas the inhibition of galectin-3 could contribute to reduce the neuroinflammatory response in neurodegenerative diseases.


Assuntos
Astrócitos/metabolismo , Galectina 1/metabolismo , Galectina 3/metabolismo , Inflamação/metabolismo , Microglia/metabolismo , Doenças Neurodegenerativas/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Galectina 3/antagonistas & inibidores , Humanos , Inflamação/tratamento farmacológico , Microglia/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico
4.
Brain Res Bull ; 37(1): 53-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7606479

RESUMO

The dominant-submissive relationship established between two rats competing for food is a model of depression and is used here to divide animals into two behaviorally distinct groups. Basal and GABA-stimulated 36CI- uptake was investigated for both dominant and submissive rats as well as the in vitro effect of the antidepressant amitriptyline (AMI). Because the antidepressant action of AMI only appears after chronic treatment, the effect of chronic injections of AMI on these behavioral and biochemical measures was also studied. Basal 36CI- uptake is significantly higher for dominant rats than for submissive rats. Increasing concentrations of AMI added to membrane vesicles enhanced 30 microM GABA-stimulated chloride uptake for dominant rats and inhibited it for submissive rats. Chronic treatment of dominant and submissive rats with AMI reversed these in vitro effects. The biochemical data correspond to the changes of the rats behavior in the dominance test after chronic treatment with AMI. However, this correlation is more clear for dominant than for submissive rats. Specific chloride influx was used as a measure of the sensitivity of GABAA receptor to GABA. This revealed different sensitivity states for GABAA receptors in tissues obtained from dominant and submissive rats. It is possible that the distinct conformational states of GABAA receptor are responsible for differences in rats behavior and in vitro effects of AMI before and after in vivo treatment of rats with this anti-depressant.


Assuntos
Amitriptilina/farmacologia , Cloro/metabolismo , Depressão/tratamento farmacológico , Dominação-Subordinação , Radioisótopos , Ácido gama-Aminobutírico/farmacologia , Análise de Variância , Animais , Depressão/psicologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Estimulação Química
8.
J Urol (Paris) ; 94(1): 43-4, 1988.
Artigo em Francês | MEDLINE | ID: mdl-3392403

RESUMO

Ureteral lesions following surgery to aorta are reported infrequently. Since 1966, when Lytton published an account of ureteral obstruction from a graft anterior to ureter, several series have been published. In the present case the initial problem was to consider the diagnosis, masked by a supposedly abdominal symptomatology. The second stage was analysis of results of urography and tests of the fluid collection. Effective treatment of this serious complication with preservation of infection of graft was obtained in the case reported by conservative surgery by means of ureteral anastomosis.


Assuntos
Prótese Vascular/efeitos adversos , Obstrução Ureteral/etiologia , Fístula Urinária/etiologia , Aorta Abdominal , Artéria Femoral , Humanos , Hidronefrose/diagnóstico , Hidronefrose/etiologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Urografia
9.
Langenbecks Arch Surg ; 387(7-8): 315-9, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12447559

RESUMO

BACKGROUND: This study investigated the possibility of local lymph node detection and lymphatic mapping following submucosal injection of an iodine-based contrast medium. METHODS AND MATERIALS: We established a contrast medium (oil/water emulsion on iodine basis) with a particle size of mainly 1.7+/-0.1 micro m. Ten rabbits received rectal submucosal injections of the contrast medium and underwent repeated projection radiography. RESULTS: Passage of the contrast medium into lymphatic vessels and storage in lymph nodes was seen in all ten animals. The best contrast was achieved within 24 and 48 h after injection. Lymph nodes were still seen in eight cases with the final radiograph on day 14. There were no clinical side effects observed. Injection sites showed mild signs of inflammation in histological examinations. Pathological signs were not detectable in lymph nodes containing the contrast media. CONCLUSIONS: This method appears useful when investigating local lymph nodes following submucosal injection due to its passage into lymphatic vessels and storage in lymph nodes.


Assuntos
Meios de Contraste/administração & dosagem , Compostos de Iodo/administração & dosagem , Doenças Linfáticas/diagnóstico por imagem , Linfografia/métodos , Mucosa/efeitos dos fármacos , Administração Retal , Animais , Modelos Animais de Doenças , Feminino , Injeções , Masculino , Coelhos , Reprodutibilidade dos Testes , Fatores de Tempo
10.
Artigo em Inglês | MEDLINE | ID: mdl-2273244

RESUMO

The effects of a zinc-deficient diet (1.5 mg/kg) on nitrogen balance in rats, fed ad libitum during 30 days, was tested. Three nitrogen balances, each of 5 days, were done on the 4th, 15th and 25th days. A pair-fed group, with a supplemented diet at 80 mg/kg of zinc, was used as control. No significant differences (P less than or equal to 0.05) in any nitrogen balances for True Digestibility, Operative Biological Value and body weight were found. Nevertheless a trend was observed in all studied variables, indicating that the proteins of the control diet were better utilized than those of the zinc-deficient ones. The variation of the Biological Value of the proteins in the zinc-deficient group along the experimental period was similar to the control group.


Assuntos
Nitrogênio/metabolismo , Zinco/deficiência , Análise de Variância , Animais , Proteínas Alimentares/metabolismo , Masculino , Ratos , Ratos Endogâmicos
11.
Bioorg Med Chem Lett ; 8(5): 555-60, 1998 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-9871617

RESUMO

Modifications of 4,4' residues of Biphalin have resulted in greater binding selectivity and biological potency for the mu opioid receptor. A higher partition coefficient across the phospholipid bilayer membrane has been achieved by using a beta-branched unusual amino acids.


Assuntos
Analgésicos/química , Encefalinas/química , Receptores Opioides mu/efeitos dos fármacos , Analgésicos/farmacologia , Animais , Encefalinas/farmacologia , Cobaias , Técnicas In Vitro , Bicamadas Lipídicas , Relação Estrutura-Atividade , Termodinâmica
12.
J Pharmacol Exp Ther ; 277(3): 1284-91, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8667189

RESUMO

The racemic compound (+/-)-BW373U86 ¿(+/-)-4-((alpha R*)- alpha-((2S*,5R*)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxy- benzyl)-N,N-diethylbenzamide dihydrochloride} is a potent delta opioid receptor agonist in the mouse vas deferens assay with little mu or kappa opioid receptor activity in the guinea pig ileum tissue preparation. In contrast, radioligand binding studies show that (+/-)-BW373U86 is only about 10-fold selective for delta over mu opioid receptors. Studies of the enantiomeric forms of (+/-)-BW373U86 and derivatives (SNC80 and related compounds) show that some of these isomers are significantly better in both receptor binding and pharmacological selectivity than (+/-)-BW373U86. In this study we have determined the binding affinities of 10 different SNC80-related compounds at cloned human delta and mu opioid receptors and measured the potency of SNC80 for the inhibition of forskolin-stimulated adenylyl cyclase. The most selective delta receptor ligand (SNC162) differed from SNC80 by the absence of the 3-methoxy substitution of the benzyl ring. The Ki for SNC162 at the delta receptor (0.625 nM) was over 8700-fold lower than that at the mu receptor (5500 nM), making this the most selective delta receptor ligand available. Reduction of the allyl side chain of SNC80 to produce radiolabeled [3H]SNC121 allowed direct measurement of the association and dissociation rate constants. SNC80 was 26-fold less potent than [D-Pen2, pCI-Phe4, D-Pen5]enkephalin in the delta receptor adenylyl cyclase inhibition assay, but showed full agonist activity with an EC50 value of 9.2 nM. The regulation of SNC80 binding affinity to the delta receptor by GTP analogs is undetectable in [3H]naltrindole binding inhibition studies, but direct binding studies with [3H]SNC121 in the presence of 100 microM 5'-guanylylimidotriphosphate show a 55% reduction in maximum binding site density consistent with a lower affinity for a part of the receptor population. Addition of 120 mM sodium chloride reduces SNC80 affinity nearly 40-fold in [3H]naltrindole binding inhibition studies. The results of these studies define specific structural features of these compounds responsible for opioid receptor interactions and suggest a possibly novel mechanism for delta receptor activation.


Assuntos
Benzamidas/química , Benzamidas/farmacologia , Piperazinas/química , Piperazinas/farmacologia , Receptores Opioides delta/efeitos dos fármacos , Receptores Opioides mu/efeitos dos fármacos , Animais , Células CHO , Cricetinae , Humanos , Cinética , Camundongos , Ensaio Radioligante , Relação Estrutura-Atividade
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