RESUMO
Previous methods of microencapsulation are unable to process particles smaller than 100 microm without organic solvents or the use of multistep processes. The present study investigates the feasiblity of a one-step spray-drying process to microencapsulate erythromycin and clarithromycin, antibiotics known to have an unpleasant, bitter taste. Mixtures of clarithromycin (5% by weight) or erythromycin (30% by weight) with a biodegradable polymer were prepared and spray-dried under specific conditions of temperature and turbine speed. This process resulted in the microencapsulation of 80% of each drug as determined by high pressure liquid chromatography. Particle size ranged from 1 to 80 microm as determined by electron microscopy. These data show that microencapsulation of macrolides using a spray-drying technique is feasible. Spray-drying microencapsulation might be useful in the formulation of palatable oral suspensions of bitter tasting drugs.
Assuntos
Antibacterianos/química , Claritromicina/química , Eritromicina/química , Antibacterianos/administração & dosagem , Cápsulas , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão , Claritromicina/administração & dosagem , Composição de Medicamentos , Eritromicina/administração & dosagem , Microscopia Eletrônica , Tamanho da PartículaRESUMO
Class I integrons are associated with carriage of genes encoding resistance to antibiotics. Expression of inserted resistance genes within these structures can be poor and, as such, the clinical relevance in terms of the effect of integron carriage on susceptibility has not been investigated. Of 163 unrelated Gram-negative isolates randomly selected from the intensive care and surgical units of 14 different hospitals in nine European countries, 43.0% (70/163) of isolates were shown to be integron-positive, with inserted gene cassettes of various sizes. Integrons were detected in isolates from all hospitals with no particular geographical variations. Integron-positive isolates were statistically more likely to be resistant to aminoglycoside, quinolone and beta8-lactam compounds, including third-generation cephalosporins and monobactams, than integron-negative isolates. Integron-positive isolates were also more likely to be multi-resistant than integron-negative isolates. This association implicates integrons in multi-drug resistance either directly through carriage of specific resistance genes, or indirectly by virtue of linkage to other resistance determinants such as extended-spectrum beta-lactamase genes. As such their widespread presence is a cause for concern. There was no association between the presence of integrons and susceptibility to cefepime, amikacin and the carbapenems, to which at least 97% of isolates were fully susceptible.
Assuntos
Antibacterianos/farmacologia , Elementos de DNA Transponíveis , Resistência a Múltiplos Medicamentos/genética , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/genética , Plasmídeos , Resistência Microbiana a Medicamentos , Europa (Continente) , Genes Bacterianos/genética , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/microbiologia , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase/métodos , Técnica de Amplificação ao Acaso de DNA PolimórficoRESUMO
We examined whether a very-low-energy all-protein diet (VLED) would produce detectable changes in iron as well as in other trace elements. Twenty-five obese patients consumed for 2 wk a VLED containing 70 g protein after a 1-wk period during which total daily energy intake was progressively reduced to 1.26 MJ. Serum iron fell sharply by approximately equal to 50% (P < 0.0001), and despite a small decrease in total-iron-binding capacity, transferrin saturation decreased from 30 +/- 11% to 18 +/- 5% (P < 0.0001). Serum ferritin did not change significantly but serum soluble transferrin receptor (sTfR), an indicator of iron deficiency, increased progressively from 4630 +/- 1110 to 6070 +/- 1390 micrograms/L (P < 0.0001). Changes in sTfR correlated inversely with prior changes in serum iron. Changes in iron metabolism did not translate into changes in erythropoiesis or red cell indexes, but the white blood cell count decreased from 7.3 +/- 1.6 to 6.2 +/- 1.9 x 10(9)/L (P < 0.002). There was no evidence of deficiency for the other trace elements and minerals tested. Daily supplementation with 200 mg Fe in 18 other subjects only partially corrected these observations despite some increase in iron stores. These results indicate that during a 2-wk VLED serum iron is significantly depressed, inducing functional tissue iron deficiency too short in duration to produce alterations in red blood cell indexes. These changes are not mediated by absolute iron deficiency, inflammation, or protein malnutrition but could be related to alterations in the iron storage and release behavior of the reticuloendothelial cell during energy deprivation alone.
Assuntos
Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Ferro/metabolismo , Obesidade/metabolismo , Adolescente , Adulto , Idoso , Proteínas Alimentares/farmacologia , Eritropoese/efeitos dos fármacos , Feminino , Humanos , Ferro/sangue , Deficiências de Ferro , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Oligoelementos/sangue , Oligoelementos/metabolismoAssuntos
Impressões Digitais de DNA , DNA Bacteriano/análise , Mycobacterium tuberculosis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Bases de Dados Factuais , Resistência a Múltiplos Medicamentos , Europa (Continente) , Humanos , Resistência a Meticilina , Mycobacterium tuberculosis/genética , Resistência às Penicilinas , Staphylococcus aureus/genética , Streptococcus pneumoniae/genéticaRESUMO
Fusarium pathogen is an uncommon cause of infections in ophthalmology. To our knowledge, there are few cases of isolated human endogenous endophthalmitis without concomitant immunodepression. An early diagnostics and therapy allowed an excellent functional recovery when compared to the reported cases in the literature.
Assuntos
Endoftalmite/microbiologia , Fusarium/isolamento & purificação , Micoses/microbiologia , Adulto , Anfotericina B/uso terapêutico , Endoftalmite/tratamento farmacológico , Endoftalmite/cirurgia , Feminino , Flucitosina/uso terapêutico , Humanos , Micoses/tratamento farmacológico , VitrectomiaAssuntos
Leucemia de Células Pilosas/terapia , Antineoplásicos/uso terapêutico , Coformicina/análogos & derivados , Coformicina/uso terapêutico , Eritropoese , Feminino , Humanos , Interferon Tipo I/uso terapêutico , Radioisótopos de Ferro , Leucemia de Células Pilosas/diagnóstico , Leucemia de Células Pilosas/fisiopatologia , Pessoa de Meia-Idade , Pentostatina , Proteínas Recombinantes , EsplenectomiaAssuntos
Inibidores da Agregação Plaquetária/farmacologia , Trombina/antagonistas & inibidores , Trombocitopenia/induzido quimicamente , Ticlopidina/análogos & derivados , Animais , Carragenina , Clopidogrel , Ácido Elágico , Feminino , Hipotensão/induzido quimicamente , Masculino , Ratos , Ratos Endogâmicos , Ticlopidina/farmacologiaRESUMO
We compared the major changes induced by ellagic acid (EA), a Hageman factor activator, in normal rats and in kininogen-deficient Brown Norway rats. In normal rats, large doses of EA induced a congestion of lymph nodes, spleen and liver, a prolongation of activated partial thromboplastin time, the consumption of prekallikrein, high molecular weight kininogen and fibrinogen, as well as the stimulation of platelets with their accumulation in lungs, liver and spleen. A systemic hypotension of long duration was also observed. The fibrinogen consumption, the thrombocytopenia and the lengthening of activated partial thromboplastin time were dose-dependent. In kininogen-deficient rats, EA induced only a minimal congestion of lymphoid tissues, the accumulation of platelets in lungs, a decrease of plasma fibrinogen and a short-lasting hypotension. It is concluded that the vascular changes induced by blood coagulation with ellagic acid resulted mainly from kinin formation.