Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Anal Bioanal Chem ; 400(5): 1251-61, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21274519

RESUMO

Nowadays, there are new technologies in high-performance liquid chromatography columns available enabling faster and more efficient separations. In this work, we compared three different types of columns for the analysis of main soy isoflavones. The evaluated columns were a conventional reverse phase particle column, a fused-core particle column, and a monolithic column. The comparison was in terms of chromatographic parameters such as resolution, asymmetry, number of theoretical plates, variability of retention time, and peak width. The lower column pressure was provided by the monolithic column, although lower chromatographic performance was achieved. Conventional and fused-core particle columns presented similar pressure. Results also indicate that direct transfer between particle and monolithic columns is not possible requiring adjustment of conditions and a different method optimization strategy. The best chromatographic performance and separation speed were observed for the fused-core particle column. Also, the effect of sample solvent on the separation and peak shape was evaluated and indicated that monolithic column is the most affected especially when using higher concentrations of acetonitrile or ethanol. Sample solvent that showed the lowest effect on the chromatographic performance of the columns was methanol. Overall evaluation of methanol and acetonitrile as mobile phase for the separation of isoflavones indicated higher chromatographic performance of acetonitrile, although methanol may be an attractive alternative. Using acetonitrile as mobile phase resulted in faster, higher resolution, narrower, and more symmetric peaks than methanol with all columns. It also generated the lower column pressure and flatter pressure profile due to mobile phase changes, and therefore, it presents a higher potential to be explored for the development of faster separation methods.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Glycine max/química , Isoflavonas/isolamento & purificação , Acetonitrilas , Cromatografia Líquida de Alta Pressão/métodos , Metanol , Pressão , Reprodutibilidade dos Testes , Solventes
2.
Anal Chim Acta ; 685(2): 204-11, 2011 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21168570

RESUMO

A fast HPLC method with diode-array absorbance detector and fluorescence detector for the analysis of 19 phenolic acids, flavan-3-ols, flavones, flavonols and caffeine in different types of samples was developed. Using a C(18) reverse-phase fused-core column separation of all compounds was achieved in less than 5 min with an overall sample-to-sample time of 10 min. Evaluation of chromatographic performance revealed excellent reproducibility, resolution, selectivity and peak symmetry. Limits of detection for all analyzed compounds ranged from 0.5 to 211 µg L(-1), while limits of quantitation ranged between 1.5 and 704 µg L(-1). The developed method was used for the determination of analytes present in different samples, including teas (black, white, green), mate, coffee, cola soft drink and an energetic drink. Concentration of the analyzed compounds occurring in the samples ranged from 0.4 to 314 mg L(-1). Caffeine was the analyte found in higher concentrations in all samples. Phytochemical profiles of the samples were consistent with those reported in the literature.


Assuntos
Bebidas/análise , Cafeína/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Fenóis/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Análise de Alimentos/instrumentação , Fenóis/química , Fatores de Tempo
3.
Talanta ; 82(5): 1986-94, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20875606

RESUMO

The recent development of fused-core technology in HPLC columns is enabling faster and highly efficient separations. This technology was evaluated for the development of an fast analysis method for the most relevant soy isoflavones. A step-by-step strategy was used to optimize temperature (25-50°C), flow rate (1.2-2.7 mL/min), mobile phase composition and equilibration time (1-5 min). Optimized conditions provided a method for the separation of all isoflavones in less than 5.8 min and total analysis time (sample-to-sample) of 11.5 min. Evaluation of chromatographic performance revealed excellent reproducibility, resolution, selectivity, peak symmetry and low limits of detection and quantification levels. The use of a fused-core column allows highly efficient, sensitive, accurate and reproducible determination of isoflavones with an outstanding sample throughout and resolution. The developed method was validated with different soy samples with a total isoflavone concentration ranging from 1941.53 to 2460.84 µg g(-1) with the predominant isoflavones being isoflavone glucosides and malonyl derivatives.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glycine max/química , Isoflavonas/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Reprodutibilidade dos Testes , Proteínas de Soja/análise , Temperatura , Fatores de Tempo
4.
Am J Med ; 100(1): 65-70, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8579089

RESUMO

OBJECTIVE: To compare the presentation of bacteremia in young and elderly patients. PATIENTS AND METHODS: Seventy-one elderly (mean age 80.4 years) and 34 younger inpatients (mean age 45.7 years) with bacteremia were prospectively studied. These were compared with a control group of 187 geriatric patients (mean age 81.3 years) with clinical signs of bacteremia but in whom blood cultures were negative. Bacteremia was defined as one or more positive blood cultures showing a pathogenic bacteria in patients with clinical signs of bacteremia. In all 105 patients with bacteremia, 16 common clinical or biological signs of the disease were immediately investigated after blood culture. Patients were classified into three groups: elder patients and young patients with bacteremia and elderly patients without bacteremia. RESULTS: Only three clinical findings of the 16 studied were found in at least 70% of the bacteremic elderly patients: fever, increased erythrocyte sedimentation rate, and a clinical indication of the source of infection. These three signs were found statistically more often in bacteremic elderly compared with nonbacteremic elderly patients (P < 0.01). Seven other signs (hypothermia, altered mental state, leukopenia, and lymphopenia) had a specificity above 80%. On a logistic regression analysis, four variables were significantly and independently associated with bacteremia in the elderly: rapid onset of infection (defined as a period < or = 48 hours between the earliest manifestation of bacteremia and the time of blood blood sample), fever, altered general state, and clinical indication of the source of infection. Younger infected patients had more chills, sweating, alter general state, altered mental state or lymphopenia than did the bacteremic elderly patients. Bacteremic elderly patients had statistically few symptoms than the young infected patients (P < 0.001). CONCLUSIONS: In elderly patients with early stage bacteremia, most of the signs or symptoms that are considered typical in the literature appear irregularly. None appeared pathognomonic. Elderly patients with bacteremia had fewer signs or symptoms than younger infected patients.


Assuntos
Envelhecimento , Bacteriemia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/sangue , Bacteriemia/microbiologia , Bacteriemia/fisiopatologia , Bactérias/isolamento & purificação , Sedimentação Sanguínea , Estudos de Casos e Controles , Feminino , Febre/fisiopatologia , Humanos , Hipotermia/fisiopatologia , Leucopenia/fisiopatologia , Modelos Logísticos , Linfopenia/fisiopatologia , Masculino , Transtornos Mentais/fisiopatologia , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Esplenomegalia/fisiopatologia , Sudorese/fisiologia
5.
J Am Geriatr Soc ; 42(9): 984-6, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8064109

RESUMO

OBJECTIVE: To determine if aging modifies the clinical presentation of hypothyroidism. DESIGN: Comparison of 24 clinical signs of hypothyroidism between elderly patients (> or = 70 years of age) and younger patients (< or = 55 years of age). SETTING: Prospective study of patients with chemically confirmed overt hypothyroidism. PATIENTS: Sixty seven elderly patients (79.3 +/- 6.7 years) and 54 younger patients (40.8 +/- 9 years) were included in the study. RESULTS: Neither mean duration of evolution nor mean thyroid-stimulating hormone (TSH) level were different between the 2 groups. Two signs were found in more than 50% of the elderly patients (fatigue and weakness). Four signs were significantly less frequent in elderly patients (chilliness, paresthesiae, weight gain, and cramps). Mean number of clinical signs in the elderly (6.6 +/- 4) was significantly smaller than in young patients (9.3 +/- 4.7) (P < 0.01). CONCLUSIONS: Our results suggest that the presentation of hypothyroidism is altered in the elderly in comparison with young patients in that there are (1) fewer signs or symptoms and (2) diminished frequency of some classical signs. Our results underline the importance of TSH measurement in the elderly.


Assuntos
Hipotireoidismo/diagnóstico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tireotropina/sangue
6.
Br J Rheumatol ; 33(7): 648-50, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8019794

RESUMO

IgG and IgM anticardiolipin antibodies (aCA) were studied prospectively in 20 consecutive patients (12 females, eight males, mean age 74.6 +/- 14 yr, range 62-86 yr) with giant cell temporal arteritis before and during corticosteroid therapy (days 7, 30, 90 and 180). IgG-aCA were present in 10 out of 20 cases and in nine out of 12 with positive temporal artery biopsy but were not found in 20 paired control subjects. During steroid therapy aCA levels returned to within the normal range in 60% of patients with positive aCA at day 7 and in 80% at day 30. In two cases aCA persisted during the 6-month follow-up despite clinical and biological success. No association was found between aCA and thrombotic events.


Assuntos
Corticosteroides/uso terapêutico , Anticorpos Anticardiolipina/análise , Arterite de Células Gigantes/tratamento farmacológico , Arterite de Células Gigantes/imunologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Arterite de Células Gigantes/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos
9.
Rev Med Interne ; 14(9): 832-40, 1993.
Artigo em Francês | MEDLINE | ID: mdl-8191101

RESUMO

Elevated aminotransferases activities are frequent in medical practice. In acute elevations, the mains causes are generally easily found (viral, drug-induced, toxic, ischemic). In moderate or prolonged elevations, the most frequent causes are steatosis (alcoholic, diabetes, obesity) and chronic hepatitis (viral B, D, C, drug-induced and auto-immune diseases.


Assuntos
Hepatite/enzimologia , Transaminases/sangue , Doença Aguda , Doença Crônica , Fígado Gorduroso/enzimologia , Humanos , Hepatopatias/enzimologia , Obesidade/enzimologia
11.
Rev Med Interne ; 13(4): 289-92, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1287770

RESUMO

Gaucher's disease is a sphingolipidosis which may be accompanied by severe pain in the bones. We report a case of Bacteroides fragilis osteomyelitis consecutive to surgical biopsy. The bone pain may be due to ischaemia of the bone or to a pyogenic osteomyelitis which is iatrogenic in most cases. The clinical and paraclinical features of these two entities are described after a review of the literature, and the main complementary examinations leading to their diagnosis are presented.


Assuntos
Doença de Gaucher/complicações , Osteomielite/etiologia , Adulto , Antibacterianos , Infecções por Bacteroides/tratamento farmacológico , Infecções por Bacteroides/microbiologia , Bacteroides fragilis/isolamento & purificação , Quimioterapia Combinada/uso terapêutico , Humanos , Imageamento por Ressonância Magnética , Masculino , Osteomielite/diagnóstico por imagem , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia , Tomografia Computadorizada por Raios X
12.
Presse Med ; 20(5): 203-6, 1991 Feb 09.
Artigo em Francês | MEDLINE | ID: mdl-1706859

RESUMO

Modifications of inter-alpha-trypsin inhibitor (ITI) in inflammatory syndromes were determined by studying its serum components: ITI 80 (the native form) and serum derivatives (SD), as well as urinary ITI derivatives (UID) excretion in 31 controls and 128 patients with inflammatory of various origins. The patients were divided into 4 groups: Group I bacterial infections (n = 29); Group II cancers (n = 50); Group III inflammatory diseases (n = 14); Group IV inflammatory syndromes due to other causes (n = 35). Other markers of inflammation were also studied. In bacterial infections and cancers ITI 80 concentrations were significantly decreased, with values of 0.55 +/- 0.15 g/l and 0.54 +/- 0.15 g/l respectively vs 0.65 +/- 0.11 g/l in controls. SD concentrations were significantly increased in all 4 groups: Gr I: 0.31 +/- 0.12 g/l; Gr II: 0.30 +/- 0.11 g/l; Gr III: 0.25 +/- 0.08 g/l; Gr IV: 0.24 +/- 0.10 g/l, as compared with 0.16 +/- 0.09 in controls. UID excretion was increased in all cases, particularly in bacterial infections and cancers (10.8 +/- 13.4 and 6.0 +/- 8.8 mg/mmol of creatinine vs 1.5 +/- 1.7 g/mmol). A significant correlation was observed between CRP levels and SD levels. In bacterial infections and cancers, a fall in ITI associated with a rise in SD and an increase in UID excretion is suggestive of degradation of the native form. In inflammatory diseases and inflammatory syndromes of other causes, the rise in SD without significant variations in ITI 80 suggests and increase in SD synthesis. The correlation between CRP and SD seems to indicate that SD are produced in the early stage of inflammatory syndromes.


Assuntos
alfa-Globulinas/análise , Infecções Bacterianas/sangue , Doenças do Tecido Conjuntivo/sangue , Glicoproteínas/análise , Neoplasias/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/urina , Doenças do Tecido Conjuntivo/urina , Humanos , Pessoa de Meia-Idade , Neoplasias/urina , Estudos Prospectivos , Valores de Referência , Síndrome , Inibidores da Tripsina/análise
13.
Gastroenterol Clin Biol ; 15(6-7): 551-3, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1916135

RESUMO

In hepatic granuloma, identification of lipogranulomas generally leads to etiological diagnosis. The case reported here was granulomatosis due to mineral oil ingestion, revealed by prolonged fever. In the literature lipogranulomas are generally asymptomatic and diagnosed at autopsy.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Febre/etiologia , Granuloma/induzido quimicamente , Óleo Mineral/efeitos adversos , Parafina/efeitos adversos , Idoso , Feminino , Granuloma/complicações , Granuloma/patologia , Humanos , Hepatopatias/complicações , Hepatopatias/patologia , Microscopia Eletrônica
18.
Gastroenterol Clin Biol ; 14(12): 1003-6, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2289657

RESUMO

The authors report a case of primary osteosarcoma of the liver in a 75 year-old man with post hepatitic B cirrhosis. The hepatic tumor was discovered on ultrasound and computed tomography. Angiography showed a hypervascularized tumor. The patient died rapidly. Diagnosis of primary osteosarcoma of the liver was established through histopathological examination of post mortem specimens and was confirmed by immunohistochemical study. From this and two other previously reported cases the authors describe the different primary hepatic tumors mimicking osteosarcoma.


Assuntos
Cirrose Hepática/complicações , Neoplasias Hepáticas/etiologia , Osteossarcoma/etiologia , Idoso , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Masculino , Osteossarcoma/diagnóstico , Osteossarcoma/patologia
19.
Rev Med Interne ; 10(6): 521-5, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2488503

RESUMO

The medicinal treatments of 639 patients aged over 65 were recorded on admission to hospital. The mean number of drugs consumed was 4.4 +/- 2.8 per patient. Drug interaction was found in 37 p. 100 of the patients on the basis of data published in the Vidal dictionary. The prevalence of interactions increased with the number of drugs prescribed. The medicinal families most frequently involved were digitalis derivatives, antiarrythmic agents, diuretics, anticoagulants and psychotropic drugs. Thirty patients (4.7 p. 100) presented with a side-effect that was directly ascribable to an interaction. Among the iatrogenic adverse reactions 11 were life-threatening, including 8 cases of severe dysrhythmia and 3 cases of gastrointestinal haemorrhages. Altogether, one-third of all iatrogenic disorders were consecutive to a drug interaction. Simple precautions would have considerably reduced the frequency of such side-effects.


Assuntos
Interações Medicamentosas , Doença Iatrogênica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino
20.
J Clin Gastroenterol ; 11(1): 95-7, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2646363

RESUMO

A case of carbimazole-induced cholestatic hepatitis is presented. A woman received carbimazole for hyperthyroidism for 3 months. Five months later, she had prompt recurrence of cholestasis parameters after rechallenge (2 days of treatment). Histologic examination showed predominantly centrilobular cholestasis. Only 5 other cases have been published in the literature. An idiosyncratic mechanism seems likely.


Assuntos
Carbimazol/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Colestase/induzido quimicamente , Doença Aguda , Idoso , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colestase/patologia , Feminino , Doença de Graves/tratamento farmacológico , Humanos , Fígado/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...