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1.
Eur J Clin Microbiol Infect Dis ; 36(1): 153-162, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27677279

RESUMO

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are increasingly documented worldwide. We recently identified two major CA-MRSA clones in Israel: USA300 and t991. Here, we assessed clinical outcomes by CA-MRSA clones and the physicians' treatment approach to CA-MRSA infections. All community-onset, clinical MRSA isolates detected during 2011-2013 by Maccabi Healthcare Services were collected and characterized phenotypically and genotypically; data were collected retrospectively from electronic medical records. Of 309 patients with MRSA infections, 64 were identified as CA-MRSA (21 %). Of the CA-MRSA infections, 72 % had skin and soft tissue infections (SSTIs), 38 % were Panton-Valentine leukocidin (PVL)+, the major clone being USA300 (n = 13, 54 %). Of PVL- isolates (n = 40, 62 %), t991 was the major clone. Age was the only predictor for PVL+ CA-MRSA infection (p < 0.001). Patients with PVL+ CA-MRSA had higher incidence of SSTI recurrences (1.061 vs. 0.647 events per patient/per year, p < 0.0001) and were more likely to have the SSTI drained (64 % vs. 21 %, p = 0.003) when compared to PVL- CA-MRSA. USA300 was more common among adults, while t991 was more common among children (p = 0.002). The physician's referral to culture results and susceptibility were the only predictors of appropriate antibiotic therapy (p < 0.001). However, only a minority of physicians referred to culture results, regardless of subspecialties. PVL+ CA-MRSA isolates caused significantly more recurrences of SSTIs and increased the need for drainage compared with PVL- isolates. Physicians' awareness of CA-MRSA as a cause of SSTIs in the community was suboptimal. Culturing of pus-producing SSTIs is crucial for providing adequate antimicrobials and elucidating MRSA epidemiology.


Assuntos
Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Padrões de Prática Médica , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Toxinas Bacterianas/genética , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , Exotoxinas/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Israel/epidemiologia , Leucocidinas/genética , Masculino , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Pessoa de Meia-Idade , Tipagem Molecular , Recidiva , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Resultado do Tratamento , Adulto Jovem
2.
Eur J Clin Microbiol Infect Dis ; 34(8): 1603-13, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25972251

RESUMO

Data on community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) in Israel are scarce. The objective of this study was to characterize the major CA-MRSA clones in Israel. All clinical MRSA isolates detected in the community during a period of 2.5 years (2011-2013) from individuals insured by a major health maintenance organization in Israel were collected, with additional data from medical records. Antibiotic susceptibility patterns and staphylococcal chromosomal cassette mec (SCCmec) typing were determined. SCCmec IV and V isolates were further typed by pulsed-field gel electrophoresis (PFGE), spa typing, and detection of a panel of toxin genes. MRSA were detected in 280 patients, mostly from skin infections. Patients with SCCmec IV (n = 120, 43 %) were younger (p < 0.0001) and reported less contact with healthcare facilities. Almost all isolates were trimethoprim-sulfamethoxazole susceptible (98 %). spa-CC032, a typical nosocomial MRSA clone, accounted for 28 % of SCCmec IV. The two major CA-MRSA clones were t008 USA300 (13 %) and t991 (10 %); t991 was isolated mainly from children (75 %), was Panton-Valentine leukocidin (PVL) negative but eta-positive, and was typically susceptible to most antibiotic groups. PVL-positive strains (n = 31) included mainly USA300 (52 %) and t019 (13 %). While multiple genetic lineages were evident among community-onset MRSA in Israel, approximately 20 % are typical CA-MRSA clones, mainly USA300 and a local clone, t991.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Genótipo , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Tipagem Molecular , Infecções Estafilocócicas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana , Feminino , Variação Genética , Humanos , Lactente , Israel/epidemiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Estudos Prospectivos , Infecções Estafilocócicas/microbiologia , Adulto Jovem
3.
Clin Microbiol Infect ; 26(12): 1687.e7-1687.e11, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32151598

RESUMO

OBJECTIVES: Zika virus (ZIKV) infection during pregnancy may cause neurological abnormalities in the foetus, and therefore fast and accurate laboratory assays are critical for rapid diagnosis. ELISA based on ZIKV NS1 protein has been developed and shown to be sensitive and highly specific; however, its negative and positive predictive values have not been tested. In this study we evaluated the ability of the NS1-based ELISA to exclude ZIKV infection and serve as a first-line screening tool for travellers. METHODS: We tested samples obtained during the peak of ZIKV infection from 1188 symptomatic and asymptomatic Israeli travellers using NS1-based IgG and IgM ELISA, real-time RT-PCR analysis and ZIKV neutralization. The Kaplan-Maier method was used to evaluate the duration of ZIKV RNA in whole blood and urine samples. RESULTS: NS1-based ELISA identified 20 true-positive, five false-positive and four false-negative cases, resulting in sensitivity and specificity of 83.3% (95%CI: 62-94%) and 97.5% (95%CI: 94-99%) respectively, and positive and negative predictive values of 80% (95%CI: 59-92%) and 98% (95%CI: 95-99%) respectively. Based on 14 RT-PCR-positive cases, median time to detect ZIKV RNA in whole blood was 17.5 days (range 5-58 days) and in urine 10 days (range 5-26 days). CONCLUSIONS: The NS1-based ELISA and RT-PCR in whole blood are highly reliable for identification of ZIKV-negative and -positive cases, respectively. Combination of both assays minimizes the risk of false-negative results, and thus allows the exclusion of ZIKV infection in travellers returning from ZIKV-endemic countries, including those who are pregnant or wish for preconception screening.


Assuntos
Viagem , Proteínas não Estruturais Virais/imunologia , Infecção por Zika virus/diagnóstico , Zika virus , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Israel , Masculino , Gravidez , RNA Viral/sangue , RNA Viral/genética , RNA Viral/urina , Reação em Cadeia da Polimerase em Tempo Real/métodos , Zika virus/genética , Zika virus/imunologia , Infecção por Zika virus/virologia
4.
QJM ; 110(12): 803-806, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29025112

RESUMO

BACKGROUND: Sodium phosphate enemas (SPEs) are widely used among hospitalized patients despite their potential to worsen renal failure. AIM: We decided to assess the extent to which this side effect is clinically relevant. DESIGN: We conducted a matched case-control, retrospective study in a cohort of hospitalized patients. METHODS: Patients treated and untreated with SPEs were matched for age, gender, baseline creatinine, usage of certain medications and several background diagnoses. Three groups of matched patients (whole study cohort, patients with baseline creatinine > 1.5 mg/dl and those with baseline creatinine > 2 mg/dl) were compared with regards to their creatinine and blood electrolyte concentrations during 3 consecutive hospitalization days after SPE application. RESULTS: Four hundred and twelve patients were included in this study of which 206 were treated by single SPEs. Exact matching was done for the whole study cohort, for 108 patients with baseline creatinine > 1.5 mg/dl and for 58 patients with baseline creatinine > 2 mg/dl. During 3 consecutive days after SPEs, the maximal blood concentrations of creatinine, phosphor and potassium did not differ significantly between treated patients and matched controls, in all three patients' groups. CONCLUSION: Application of SPEs neither seem to worsen mild to moderate renal failure, nor are associated with hyperphosphatemia or hyperkalemia in patients hospitalized in internal medicine departments.

5.
J Clin Pharmacol ; 38(4): 373-81, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9590466

RESUMO

In vitro and animal experiments have characterized KA 672-HCl as a potent functional antagonist of excitatory amino acid-induced convulsions and mortality. In receptor-binding studies, the compound displayed high affinities to several serotoninergic, adrenergic, and dopaminergic receptors and to the sigma receptor. The potential for short- and long-term toxicity of KA 672-HCl in rats and dogs was found to be low. Double-blind, randomized, placebo-controlled studies were undertaken in healthy volunteers ranging from 52 to 74 years of age to determine tolerability, safety, and preliminary pharmacokinetics of single and repeated doses in humans. Single doses up to 40 mg were well tolerated, with no difference in effect from placebo. At 60 mg, approximately half of the volunteers experienced a moderate drug-related orthostatic syndrome. After repeated doses of 10 or 20 mg KA 672-HCl for 14 days only minor adverse events of mild intensity were reported with no clear relation to dose or a clinically relevant difference from placebo. A mild decrease in semisupine and standing blood pressure 4 hours after administration was observed in the 20 mg group with no occurrence of orthostasis. Linear pharmacokinetics were observed after repeated doses. However, this was not the case after single-dose administration, as generally higher plasma concentrations were observed after the 20-mg dose than would have been predicted from the 10-mg data. The mean terminal phase half-life after the 20 mg dose was 11.1 hours and 13.7 hours after repeated and single doses, respectively. The safety and tolerability data support a continuation of therapeutic trials. KA 672-HCl is currently entering phase II development.


Assuntos
Benzopiranos/efeitos adversos , Benzopiranos/farmacocinética , Demência/tratamento farmacológico , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Administração Oral , Idoso , Benzopiranos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/administração & dosagem
6.
Peptides ; 17(7): 1083-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8959740

RESUMO

The intestinal enzymatic degradation of the immunomodulating peptides thymotrinan (TP3), thymocartin (TP4), and thymopentin (TP5), three oligopeptides derived from the naturally occurring thymus hormone thymopoietin, was investigated to evaluate their potential for peroral drug delivery. In the presence of brush-border membrane vesicles, crude pancreas extract and everted rings from duodenum, jejunum, ileum, and colon, all peptides were shown to be degraded both by pancreatic enzymes and brush-border aminopeptidases. Degradation clearances (Cldeg) of TP3, TP4, and TP5 were calculated for a quantitative comparison of peptide stability. In the presence of crude pancreas extract, there was a rapid degradation of TP5 (Cldeg 17.9 ml/min) in comparison with TP3 and TP4 (Cldeg 0.95 and 0.56 ml/min, respectively, at 0.2 mM peptide concentration) caused by the cleavage of the C-terminal tyrosine by carboxypeptidase A, whereas TP3 and TP4 underwent hydrolysis by aminopeptidase N. In the presence of brush-border membrane vesicles, the degradation clearances were 3.9, 3.1, and 2.4 ml/min at 0.2 mM concentrations of TP4, TP5, and TP3, respectively. The clearance of all peptides was lowered with increasing peptide concentrations, indicating saturable degradation processes. The degradation of the thymopoietin oligopeptides in the presence of brush-border membrane enzymes was exclusively catalyzed by aminopeptidase N. The degradation of all peptides was highly dependent on the intestinal segment, with the lowest degradation clearance observed in the colon.


Assuntos
Enzimas/metabolismo , Intestinos/enzimologia , Microvilosidades/enzimologia , Pâncreas/enzimologia , Timopoietinas/metabolismo , Animais , Intestinos/ultraestrutura , Cinética , Pâncreas/ultraestrutura , Suínos , Timopentina/metabolismo
7.
Brain Res ; 456(2): 350-6, 1988 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-3208084

RESUMO

Local cerebral glucose utilization (LCGU) was measured in 45 regions of the rat brain during chronic nicotine infusion using the quantitative autoradiographic 2-deoxy-D-[1-14C]glucose method described by Sokoloff et al. [J. Neurochem., 28 (1977) 897-916]. Osmotic minipumps, filled with L-nicotine, were implanted 14 days before the measurement of LCGU. The infused nicotine dose of 12.5 micrograms/kg/min resulted in a plasma nicotine concentration of 77 +/- 17 and a plasma cotinine concentration of 504 +/- 137 (mean +/- S.E.M.) ng/ml plasma. One day before the LCGU experiment was performed, spontaneous locomotor activity was measured and found to be reduced significantly. Measurement of LCGU showed a significant increase in 6 of the 45 brain structures examined, i.e. globus pallidus, septal nucleus, lateral geniculate body, superior colliculus (superficial grey layer), interpeduncular nucleus and optic chiasm. These results are partly congruent with previous data of our group obtained during acute nicotine infusion, insofar as LCGU was increased in the optic chiasm, the lateral geniculate body, the superior colliculus, and the interpeduncular nucleus. On the other hand, the increased LCGU in the globus pallidus and septal nucleus occurred during chronic infusion only; other structures were not affected by chronic infusion although their LCGU had been raised during acute infusion. It is concluded that chronic nicotine infusion has distinct effects on the functional activity of several brain structures which are partly congruent with those affected during acute nicotine infusion and partly divergent from them.


Assuntos
Encéfalo/metabolismo , Desoxiaçúcares/metabolismo , Desoxiglucose/metabolismo , Nicotina/farmacologia , Animais , Autorradiografia , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Radioisótopos de Carbono , Frequência Cardíaca/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Especificidade de Órgãos , Ratos , Ratos Endogâmicos , Valores de Referência , Vigília
8.
J Neurol ; 225(4): 231-6, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6169802

RESUMO

Cerebrospinal fluid (CSF) from 105 patients was analyzed by radioimmunoassay for the presence of material cross-reactive with peptide 89-169 of bovine myelin basic protein (BP). In a group of 72 multiple sclerosis patients, 52 showed higher BP content than the control group, i.e. more than 2 ng/ml CSF. Increased BP or BP fragments could be detected in CSF from almost all patients who recently (within 2 weeks) had had an acute episode, or after deterioration in the progressive form of the disease. Fifteen to 30 days after the onset of exacerbation or in a stable period, BP content decreases and in the slowly progressive form was in the range of the control group with one exception. BP content was also elevated in the CSF of patients with other neurological diseases. The presence of BP in the CSF from patients with isolated retrobulbar neuritis is of particular interest. Thus the presence of material cross-reactive with BP fragment 89-169 is not specific for multiple sclerosis, but is a useful parameter in diagnosis and evaluation of MS.


Assuntos
Esclerose Múltipla/diagnóstico , Proteína Básica da Mielina/líquido cefalorraquidiano , Doenças do Sistema Nervoso/líquido cefalorraquidiano , Transtornos Cerebrovasculares/diagnóstico , Humanos , Neurossífilis/diagnóstico , Neurite Óptica/diagnóstico , Polirradiculoneuropatia/diagnóstico , Radioimunoensaio
9.
Toxicol Lett ; 35(1): 135-40, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3544340

RESUMO

20 non-smokers on a defined diet low in polycyclic aromatic hydrocarbons (PAH) were exposed to environmental tobacco smoke (ETS) in an unventilated room for 8 h. The urinary mutagenicity in the 24-h urine samples as tested with the Salmonella (TA98) microsome assay did not significantly increase after exposure to either 10 ppm CO or 20-25 ppm CO. We conclude that exposure of non-smokers to ETS does not lead to an increase in their urinary mutagenicity, provided the exposure conditions are within a realistic range.


Assuntos
Mutagênicos/urina , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Carboxihemoglobina/metabolismo , Cotinina/metabolismo , Dieta , Ambiente Controlado , Humanos , Testes de Mutagenicidade , Salmonella typhimurium/efeitos dos fármacos , Fumar
10.
Toxicol Lett ; 35(1): 35-44, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3810680

RESUMO

Quality control studies on cotinine measurements following low level environmental tobacco smoke (ETS) exposure are rare. The exposure to ETS was controlled and systematically changed in a series of experiments in a climatic chamber. Healthy nonsmoking volunteers were exposed to ETS simultaneously. The duration and level of exposure varied using high (8, 17 and 25 ppm CO), and low (2 and 5 ppm CO) exposure levels. The variation between radioimmunoassay (RIA) and gas chromatography (GC) was high as was the variation between the results of RIA laboratories. There was also a high within-laboratory-variation. A 1:10 dilution seems to be preferable over a 1:3 dilution. Freezing the urine samples immediately after collection led to the detection of higher cotinine values than freezing the samples 24 h after collection. Highly reliable data for cotinine were obtained when the urine samples were kept frozen immediately after collection and fractionated sampling over 48-72 h was used. Our data show that estimating low-level ETS exposure by measuring urinary cotinine is highly susceptible to uncontrolled variation and errors. Sufficiently reliable estimates of low-level ETS exposure can be made only when fractionated sampling over 48-72 h is used and when the urine samples are kept frozen just after collection.


Assuntos
Cotinina/análise , Pirrolidinonas/análise , Poluição por Fumaça de Tabaco/análise , Cromatografia Gasosa , Cotinina/sangue , Cotinina/urina , Relação Dose-Resposta a Droga , Congelamento , Humanos , Nicotina/análise , Nicotina/sangue , Nicotina/urina , Radioimunoensaio/normas , Saliva/análise , Estatística como Assunto
11.
Toxicol Lett ; 35(1): 45-52, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3810681

RESUMO

An interlaboratory study aimed at determining nicotine and cotinine in human serum and urine was carried out. 11 laboratories from 6 countries, all experienced in performing nicotine and cotinine determinations in biological fluids by radioimmunoassay (RIA) and/or gas chromatography (GC) were involved. Each of them received 18 serum and 18 urine samples. The specimens were obtained from 8 smokers and 10 non-smokers; 2 samples from non-smokers were spiked with defined amounts of nicotine and cotinine. All the laboratories distinguished perfectly between the smokers and the non-smokers and according to cotinine levels in serum the laboratories ranked the samples with good agreement. There were systematic differences in the absolute values between the laboratories. The ratios of urinary cotinine concentrations between active and passive smokers differed widely from laboratory to laboratory. The reasons for this are not yet known and necessitate further investigation.


Assuntos
Cotinina/análise , Nicotina/análise , Pirrolidinonas/análise , Fumar , Poluição por Fumaça de Tabaco/análise , Cromatografia Gasosa/normas , Cotinina/sangue , Cotinina/urina , Humanos , Nicotina/sangue , Nicotina/urina , Radioimunoensaio/normas
12.
J Biochem Biophys Methods ; 5(4): 237-9, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7310046

RESUMO

An ultracentrifugation procedure is described to concentrate protein solutions on the microliter scale. Protein solutions were centrifuged in U-shaped lengths of polyethylene tubing at 160000 X g for 15 h and thereafter fractionated by cutting the tubing. The method can be performed in a conventional ultracentrifuge and needs no special equipment.


Assuntos
Proteínas do Líquido Cefalorraquidiano/isolamento & purificação , Proteínas/isolamento & purificação , Animais , Proteínas Sanguíneas/isolamento & purificação , Humanos , Microquímica , Polietilenos , Ultracentrifugação/métodos
13.
Int J Clin Pharmacol Ther ; 34(1): 6-11, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8688997

RESUMO

Losigamone (AO-33), a new potential antiepileptic drug, was tested in 52 healthy male volunteers in 4 placebo-controlled phase I studies. In study 1 single doses of 100, 200, 300, 500, 700, and 1,000 mg losigamone were given as a fast releasing capsule to 12 subjects. The pharmacokinetics of losigamone measured after administration of 100, 300, and 700 mg was linear. Clearance and t1/2 were about 350 ml/min and 4 h, respectively, the Cmax values of 0.7, 1.7, and 4.4 micrograms/ml were reached after 2.5 h. In study 2,500 mg losigamone were given as a fast release capsule for 6 days (t.i.d.) to 12 subjects. There was a small but statistically significant decrease for the AUC but no change in t1/2, Cmax or tmax comparing single dose kinetics on day 1 and 8. There appeared to be no change in caffeine clearance on days 1 and 9. Study 2 was repeated in 20 volunteers with a film-coated tablet. Pharmacokinetic parameters appeared to be unaffected by this change in galenical formulation. In study 4 daily doses of 400, 1,200, and 1,800 mg losigamone were given 28 days to 24 subjects. The kinetics of caffeine and antipyrine were compared on days 1 and 29. With the exception of t1/2 for antipyrine in the 400 mg group there was no statistically significant change in pharmacokinetic parameters. Generally, losigamone was well tolerated and no serious adverse side-effects occurred. In some subjects a reversible increase in transaminases was observed.


Assuntos
Anticonvulsivantes/farmacocinética , Furanos/farmacocinética , Administração Oral , Alanina Transaminase/sangue , Alanina Transaminase/metabolismo , Anti-Inflamatórios não Esteroides/farmacocinética , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/sangue , Anticonvulsivantes/química , Antipirina/farmacocinética , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/metabolismo , Cafeína/farmacocinética , Estimulantes do Sistema Nervoso Central/farmacocinética , Método Duplo-Cego , Furanos/administração & dosagem , Furanos/efeitos adversos , Furanos/sangue , Furanos/química , Humanos , Masculino
14.
J Pharm Pharmacol ; 54(11): 1507-14, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12495553

RESUMO

To be effective, herbal medicinal products are expected to meet comparable standards concerning the assessment of efficacy, safety and biopharmaceutical quality as chemically defined synthetic drugs as food supplements. However, these requirements are often not fulfilled, particularly regarding the characterization of biopharmaceutical properties such as in-vitro dissolution and in-vivo bioavailability. With respect to the relevance of biopharmaceutical quality of herbal medicinal products, two different Ginkgo biloba brands (test product: Ginkgo biloba capsules; reference product: Ginkgold) were analysed for dissolution rates and bioavailability of the most relevant active ingredients. Dissolution rates at pH 1 and 4.5 were determined according to the USP 23. The relative bioavailability of ginkgolide A, ginkgolide B and bilobalide was investigated after single oral administration of 120 mg Ginkgo biloba extract as tablets or capsules. Bioavailability data (area under the curve and peak concentration in plasma) were clearly different and did not show bioequivalence of test and reference products. The slow in-vitro dissolution of the test product resulted in a large decrease in bioavailability. These results indicate for the first time that the pharmaceutical properties of a herbal medicinal product have a significant impact on the rate and extent of drug absorption, and very likely on efficacy in humans.


Assuntos
Diterpenos , Ginkgo biloba/química , Extratos Vegetais/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Ciclopentanos/sangue , Furanos/sangue , Cromatografia Gasosa-Espectrometria de Massas , Ginkgolídeos , Humanos , Concentração de Íons de Hidrogênio , Lactonas/sangue , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/química , Solubilidade , Tecnologia Farmacêutica , Equivalência Terapêutica
15.
Int Angiol ; 6(1): 29-36, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3624944

RESUMO

Nicotine was injected intraperitoneally to rats and 2 h later lipoprotein lipase was determined in isolated perfused hearts. There was a significant increase in heparin releasable lipoprotein lipase activity which represents the functional pool without increase in total enzyme activity. When 1 microliter/h of a solution of nicotine (120 mg/ml) was delivered for 3 days from subcutaneously implanted miniosmotic pumps, total lipoprotein lipase activity in the heart increased 1.5-3.0 fold. Endogenous lipoprotein lipase activity in plasma doubled and there was a significant fall in plasma triglyceride levels. The effect of nicotine on heart lipoprotein lipase activity was evident also after 6 days of continuous delivery and was accompanied by a fall in adipose tissue lipoprotein lipase activity. No effect was seen when the dose of nicotine was halved. A positive correlation was seen between plasma nicotine levels and heart lipoprotein lipase activity, while adipose tissue lipoprotein lipase correlated negatively with plasma nicotine levels. Chronic administration of nicotine was accompanied by either weight loss or diminished weight gain. It is concluded that in the rat the acute effect of nicotine on the shift of lipoprotein lipase to the functional pool could be related to enhanced beta-adrenergic stimulation. The chronic effect of nicotine could have been mediated by the loss in body weight, due to reduced caloric intake.


Assuntos
Lipase Lipoproteica/sangue , Miocárdio/enzimologia , Nicotina/administração & dosagem , Animais , Glicemia/metabolismo , Cotinina/sangue , Lipídeos/sangue , Nicotina/sangue , Ratos
16.
Pharmazie ; 51(8): 577-81, 1996 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-8975251

RESUMO

With a specific radioimmunoassay the pharmacokinetics and relative bioavailability of escin was measured after administration of different formulations containing Aesculus-extract. Of special interest was the relative bioavailability of escin after administration of a newly developed film-coated tablet with sustained release in comparison to a reference formulation. In a cross-over steady-state study in 24 volunteers bioequivalence of test and reference preparation could be demonstrated. The 90% confidence interval of the AUC (O-tau) was 98.3 to 120.9%.


Assuntos
Escina/farmacocinética , Plantas Medicinais/química , Adulto , Disponibilidade Biológica , Estudos Cross-Over , Escina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Comprimidos com Revestimento Entérico , Equivalência Terapêutica , Extratos de Tecidos/farmacocinética
17.
Eur J Drug Metab Pharmacokinet ; 23(1): 45-53, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9625272

RESUMO

Losigamone ((+/-)-(R*,S*)-5-(2-chlorophenylhydroxymethyl)-4-methoxy-2 (5H)-furanone; AO-33) is a new potential antiepileptic drug undergoing clinical development. In a crossover study, 200 mg [14C]-labelled Losigamone, as well as 100 mg of each of the unlabelled enantiomers, was administered to 5 healthy volunteers as an oral suspension. The objectives of the study were to determine the mode of elimination, the excretion balance, metabolic profile, the in vitro and in vivo binding to plasma proteins and the pharmacokinetics of both enantiomers in plasma. From the plasma concentration-time profiles of [14C]-radioactivity and unchanged Losigamone it can be concluded that the absorption of Losigamone occurs very rapidly and the plasma concentration of the parent compound versus total radioactivity was consistently about 40%. An overall recovery of total radioactivity of about 97% with 85% in urine and 12% in faeces was found. Protein binding was 50%. Losigamone was extensively metabolized, with only traces of unchanged drug found in urine. The predominant metabolic pathways are hydroxylation and conjugation. After administration of the pure enantiomers, significant differences in pharmacokinetics were observed. The mean oral clearance of the (-)-enantiomer was 1863 ml/min and of the (+)-enantiomer was 171 ml/min. There was no chiral inversion after administration of the enantiomers.


Assuntos
Anticonvulsivantes/farmacocinética , Furanos/farmacocinética , Administração Oral , Adulto , Proteínas Sanguíneas/metabolismo , Radioisótopos de Carbono , Estudos Cross-Over , Furanos/administração & dosagem , Humanos , Masculino , Ligação Proteica , Estereoisomerismo
18.
Therapie ; 50(2): 137-44, 1995.
Artigo em Francês | MEDLINE | ID: mdl-7631288

RESUMO

The pharmacokinetics of Ginkgolide A, Ginkgolide B and Bilobalide, which are compounds extracted from the dried leaves of the Ginkgo biloba tree, were investigated in 12 young healthy volunteers (six men and six women; mean +/- SD age = 25 +/- 5 years) after single-dose administration of Ginkgo biloba extract. Subjects were given, on three occasions, Ginkgo biloba extract as a solution either orally (in fasting conditions and after a standard meal) or intravenously; corresponding to single doses of Ginkgolide A, Ginkgolide B and Bilobalide ranging from 0.90 mg to 3.36 mg. After each dosing, blood and urine samples were collected for up to 36 h and 48 h, for measurements of Ginkgolide A, Ginkgolide B and Bilobalide. Plasma and urine concentrations of these compounds were quantitatively measured by gas chromatography/mass spectrometry using negative chemical ionization, by applying a very sensitive method which allowed plasma concentrations as low as 0.2 ng/ml of each compound to be measured. When given orally, while fasting, the extents of bioavailability are high, as shown by bioavailability coefficients (FAUC) mean (+/- SD) values equal to 0.80 (+/- 0.09), 0.88 (+/- 0.21) and 0.79 (+/- 0.30) for Ginkgolide A, Ginkgolide B and Bilobalide respectively. Food intake does not change AUC quantitatively but increases Tmax. For the three compounds of interest, after oral dosing while fasting, differences can be noted for the elimination half-lives (T1/2Z), which exhibit mean values equal to 4.50, 10.57 and 3.21 h, as well as mean residence times (MRT), equal to 5.86, 11.25 and 4.89 h, for Ginkgolide A, Ginkgolide B and Bilobalide respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ciclopentanos/farmacocinética , Diterpenos , Fibrinolíticos/farmacocinética , Furanos/farmacocinética , Lactonas/farmacocinética , Administração Oral , Adulto , Análise de Variância , Estudos Cross-Over , Ciclopentanos/administração & dosagem , Feminino , Fibrinolíticos/administração & dosagem , Furanos/administração & dosagem , Ginkgo biloba , Ginkgolídeos , Efeito do Trabalhador Sadio , Humanos , Injeções Intravenosas , Lactonas/administração & dosagem , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética
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