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1.
Int J Pharm ; 646: 123473, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37788730

RESUMO

Liver fibrosis is a condition characterized by the accumulation of extracellular matrix (ECM) arising from the myofibroblastic transdifferentiation of hepatic stellate cells (HSCs) occurring as the natural response to liver damage. To date, no pharmacological treatments have been specifically approved for liver fibrosis. We recently reported a beneficial effect of polyenylphosphatidylcholines (PPCs)-rich formulations in reverting fibrogenic features of HSCs. However, unsaturated phospholipids' properties pose a constant challenge to the development of tablets as preferred patient-centric dosage form. Profiting from the advantageous physical properties of the PPCs-rich Soluthin® S 80 M, we developed a tablet formulation incorporating 70% w/w of this bioactive lipid. Tablets were characterized via X-ray powder diffraction, thermogravimetry, and Raman confocal imaging, and passed the major compendial requirements. To mimic physiological absorption after oral intake, phospholipids extracted from tablets were reconstituted as protein-free chylomicron (PFC)-like emulsions and tested on the fibrogenic human HSC line LX-2 and on primary cirrhotic rat hepatic stellate cells (PRHSC). Lipids extracted from tablets and reconstituted in buffer or as PFC-like emulsions exerted the same antifibrotic effect on both activated LX-2 and PRHSCs as observed with plain S 80 M liposomes, showing that the manufacturing process did not interfere with the bioactivity of PPCs.


Assuntos
Excipientes , Fígado , Humanos , Ratos , Animais , Excipientes/farmacologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Comprimidos/farmacologia , Células Estreladas do Fígado
2.
AMIA Annu Symp Proc ; 2016: 1900-1909, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28269949

RESUMO

Authors of biomedical articles use comparison sentences to communicate the findings of a study, and to compare the results of the current study with earlier studies. The Claim Framework defines a comparison claim as a sentence that includes at least two entities that are being compared, and an endpoint that captures the way in which the entities are compared. Although automated methods have been developed to identify comparison sentences from the text, identifying the role that a specific noun plays (i.e. entity or endpoint) is much more difficult. Automated methods have been successful at identifying the second entity, but classification models were unable to clearly differentiate between the first entity and the endpoint. We show empirically that establishing if head noun is an amount or measure provides a statistically significant improvement that increases the endpoint precision from 0.42 to 0.56 on longer and from 0.51 to 0.58 on shorter sentences and recall from 0.64 to 0.71 on longer and from 0.69 to 0.74 on shorter sentences. The differences were not statistically significant for the second compared entity.


Assuntos
Metanálise como Assunto , Máquina de Vetores de Suporte , Animais , Pesquisa Biomédica , Diabetes Mellitus , Humanos , Linguística , Processamento de Linguagem Natural , Publicações/tendências , Literatura de Revisão como Assunto
3.
J Biomed Inform ; 56: 42-56, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26003938

RESUMO

Preparing a systematic review can take hundreds of hours to complete, but the process of reconciling different results from multiple studies is the bedrock of evidence-based medicine. We introduce a two-step approach to automatically extract three facets - two entities (the agent and object) and the way in which the entities are compared (the endpoint) - from direct comparative sentences in full-text articles. The system does not require a user to predefine entities in advance and thus can be used in domains where entity recognition is difficult or unavailable. As with a systematic review, the tabular summary produced using the automatically extracted facets shows how experimental results differ between studies. Experiments were conducted using a collection of more than 2million sentences from three journals Diabetes, Carcinogenesis and Endocrinology and two machine learning algorithms, support vector machines (SVM) and a general linear model (GLM). F1 and accuracy measures for the SVM and GLM differed by only 0.01 across all three comparison facets in a randomly selected set of test sentences. The system achieved the best performance of 92% for objects, whereas the accuracy for both agent and endpoints was 73%. F1 scores were higher for objects (0.77) than for endpoints (0.51) or agents (0.47). A situated evaluation of Metformin, a drug to treat diabetes, showed system accuracy of 95%, 83% and 79% for the object, endpoint and agent respectively. The situated evaluation had higher F1 scores of 0.88, 0.64 and 0.62 for object, endpoint, and agent respectively. On average, only 5.31% of the sentences in a full-text article are direct comparisons, but the tabular summaries suggest that these sentences provide a rich source of currently underutilized information that can be used to accelerate the systematic review process and identify gaps where future research should be focused.


Assuntos
Pesquisa Comparativa da Efetividade , Metformina , Revisões Sistemáticas como Assunto , Feminino , Humanos , Algoritmos , Glicemia/análise , Mineração de Dados/métodos , Processamento Eletrônico de Dados , Medicina Baseada em Evidências , Insulina/química , Idioma , Modelos Lineares , Linguística , Aprendizado de Máquina , Metformina/uso terapêutico , Processamento de Linguagem Natural , Cloridrato de Raloxifeno/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Máquina de Vetores de Suporte , Tamoxifeno/análogos & derivados , Tamoxifeno/uso terapêutico , Útero/efeitos dos fármacos
4.
Arh Hig Rada Toksikol ; 55(4): 243-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15584550

RESUMO

The aim of our study was to find whether ochratoxin A (OTA) induces the apoptosis and/or necrosis of kidney tissue in rats. In the first experiment, the highest number of apoptotic cells was found in rats sacrificed one day after OTA administration (1.00 mg/kg b.w., i.p.). The number of apoptotic cells reduced gradually and they were not seen nine days after OTA administration. A possible dose-dependence of histological changes was checked in kidney tissue of rats given 0.25, 0.50 or 1.00 mg of OTA/kg b.w., i.p. three times a week for four weeks. The number of apoptotic cells showed a clear dose-dependence, but necrosis was absent even at the highest doses. The time-dependent appearance of lesions related to OTA administration was checked by administering 0.50 mg OTA/kg body weight to rats, and sacrificing them one day after 1, 3, 6, and 9 doses/administrations, or 6 and 21 day after 12 doses/administrations. Long-term administration is associated with continued and increased apoptosis without necrosis, suggestive of OTA's role in the pathogenesis of progressive renal atrophy.


Assuntos
Apoptose/efeitos dos fármacos , Carcinógenos/toxicidade , Rim/efeitos dos fármacos , Ocratoxinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Rim/patologia , Ratos , Ratos Wistar
5.
Artigo em Inglês | MEDLINE | ID: mdl-14643512

RESUMO

This paper describes two different procedures for extraction of ochratoxin A (OTA) from urine samples: one using acidic chloroform-methanol mixture, followed by solid-phase extraction (SPE) clean-up and the other using commercial Chem Elut columns and a chloroform-formic acid mixture. The recovery of OTA using the procedure with silica gel columns was 82% with a R.S.D. < 8.4% and the detection and quantitation limits were 0.5 and 1.5 ng OTA/ml, respectively. The recovery of OTA in the second procedure with urine samples purified only on commercial Chem Elut columns was 95% with R.S.D. < 4.0%, and detection and quantitation limits 0.3 and 0.9 ng/ml, respectively. Both procedures of OTA extraction effectively eliminate interfering substances and give reliable and repeatable results. However, the procedure with Chem Elut columns gave higher recovery and lower detection and quantitation limits. It was successfully applied in determining OTA in human urine samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ocratoxinas/urina , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência
6.
Arch Toxicol ; 76(3): 173-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11967623

RESUMO

The objective of this study was to evaluate the efficacy of thienyl phencyclidine (tenocyclidine, TCP) and its newly synthesized adamantyl derivatives containing piperidine (TAPIP), pyrolidine (TAPIR) and morpholine (TAMORF) groups, which were tested with or without standard therapy in mice poisoned with organophosphates (OPs) and carbamates. These compounds with potential activity at the N-methyl- D-aspartate and muscarinic receptors showed low acute toxicity, having LD50 values varying from 106.00 mg/kg (TCP) to >504.00 mg/kg body weight (TAMORF). TCP and its adamantyl derivatives were administered intraperitoneally (2.5 mg/kg body weight) together with atropine (10.0 mg/kg body weight) and with or without 1/4 LD50 of the oxime HI-6. Each compound administered with atropine had a therapeutic effect against poisoning with carbamates propoxur, aldicarb and Ro 02-0683 (protective ratio of tenocyclidines was from 3.99 LD50 of aldicarb to >16.00 LD50 for propoxur). However, the efficacy of those compounds in combination with atropine was lower against poisoning with the OP insecticide dichlorvos (DDVP) and chemical warfare agents soman and tabun. In soman-poisoned mice, the best therapeutic effects were obtained with the combination of HI-6 plus atropine and test compounds, with protective ratios being from 5.40 to 7.12 LD50 of soman. The results suggest that TCP and adamantyl tenocyclidines could be used in combination with atropine as antidotes in carbamate poisoning and as adjuvant therapy to HI-6 and atropine in soman poisoning.


Assuntos
Adamantano/análogos & derivados , Antídotos/uso terapêutico , Carbamatos/toxicidade , Reativadores da Colinesterase/uso terapêutico , Intoxicação por Organofosfatos , Intoxicação/prevenção & controle , Compostos de Piridínio/uso terapêutico , Animais , Atropina/uso terapêutico , Quimioterapia Combinada , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos CBA , Oximas , Compostos de Piridínio/química
7.
Arh Hig Rada Toksikol ; 53(4): 275-81, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12828128

RESUMO

This paper describes the effects of dichlorvos (DDVP) on butyrylcholinesterase (BuChE) activity with possible consequences for lipid and lipoprotein metabolism in rats. The rats of both sexes were given a single and multiple doses of DDVP (8.0 mg/kg body weight) with two-day intervals between administrations, ensuring the continuous inhibition of BuChE activity without lethal outcome. BuChE activity was measured in plasma, liver, and white and brown adipose tissue. The recovery of BuChE activity was observed only in white adipose tissue of female rats 10 days after treatment. Our results show that DDVP significantly decreases BuChE activity in female and male rat plasma (40-60%; P < 0.05), and significantly increases triglycerides (60-600%; P < 0.05) and total cholesterol (35-75%; P < 0.05). In contrast to the increased HDL-cholesterol (20-30%; P < 0.05), LDL-cholesterol decreased (30-40%; P < 0.05). The decrease of BuChE activity and the changes in concentrations of lipids and lipoproteins were observed throughout the experiment. Our results contribute to the hypothesis that BuChE may play a role in lipid and lipoprotein metabolism.


Assuntos
Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Diclorvós/farmacologia , Metabolismo dos Lipídeos , Animais , Feminino , Masculino , Ratos , Ratos Wistar
8.
Arh Hig Rada Toksikol ; 53(3): 185-90, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12557470

RESUMO

The paper describes the catalytic activity of butyrylcholinesterase (BuChE) measured in plasma, liver, white adipose tissue, heart, and brain of rats intraperitoneally administered a single non-lethal dose of cycloheximide (2.0 mg/kg body weight; CHM). The BuChE assay was performed on rats of both sexes either administered CHM or saline (controls), and killed 2, 3, 4, 5, 10 days later. A significant decrease of BuChE catalytic activity was observed in all tested tissues except plasma. In animals of both sexes, the lowest BuChE catalytic activity was found in the liver (2-6%), while it was higher in white adipose tissue, heart, and brain. However, the respective values remained significantly different from controls (33-67%, 49-62%, and 14-71% in males, and 24-82%, 72-86%, and 33-67% in females). Since there was no effect of CHM on BuChE catalytic activity in plasma, the data suggest that CHM inhibits the synthesis of BuChE rather than its active site.


Assuntos
Antifúngicos/farmacologia , Butirilcolinesterase/metabolismo , Cicloeximida/farmacologia , Inibidores Enzimáticos/farmacologia , Animais , Feminino , Masculino , Ratos , Ratos Wistar
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