RESUMO
Casein entrapped within gel microbeads using alginate, amidated LM pectin, gellan gum and a system containing a mixture of these polysaccharides (pectin:gellan:alginate, 1/3: 1/3: 1/3), were obtained by ionic gelation in a high-pressure capillary apparatus. Hydrogenated vegetable fat was also added to produce the gel microbeads and protein release in all the systems was measured, including from freeze-dried capsules containing protein and fat. Encapsulation efficiency, capsule size and morphology were evaluated as well as the protein release profile. Encapsulation efficiencies from 83.7 to 90.7% were obtained for the protein capsules and from 71.8 to 95.4% for those containing protein and fat. Greater release was observed from gel microbeads without fat where alginate presented the greatest diffusion (100%) and the system with a mixture of polyssacharides, the best barrier, with protein retention of 90% after 240 min in solution. The fat containing gel microbeads presented good percent retentions and both the gel microbeads and the dry microbeads showed similar percentages for release. The majority of the systems studied showed a burst effect on release. Gel microbeads size distribution was similar, both with and without fat, and independent of the matrix material, the mean size being 150microm. The morphological observations showed that the gel microbeads were spheroidal with a homogenous distribution of fat droplets in the microcapsules. Agglomeration occurred on drying but many particles maintained a partially spheroidal form, with a configuration of solid material.
Assuntos
Caseínas/farmacocinética , Coloides/química , Preparações de Ação Retardada/farmacocinética , Dessecação/métodos , Microesferas , Alginatos/química , Cápsulas , Caseínas/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Géis , Concentração de Íons de Hidrogênio , Peso Molecular , Pectinas/química , Polissacarídeos Bacterianos/química , Óleo de Soja/química , Tecnologia Farmacêutica/métodos , Ácidos Graxos trans/química , Viscosidade , Água/análiseRESUMO
Pseudomonas aeruginosa has been shown to enter into human endothelial cells in vitro. To ascertain the effects of bacterial intracellular (IC) infection, endothelial cells were exposed to PAK and PAO-1 strains for 1 h and treated with gentamicin in culture medium for different periods. P. aeruginosa induced a significant production of superoxide and hydrogen peroxide by endothelial cells. Concentrations of IC bacteria were reduced progressively with time and no viable PAO-1 was detected at 24 h after infection. However, IC infection led to killing of 32.2%+/-2.9 and 51.8%+/-3.5 of the cells infected with PAK and PAO-1, respectively, as determined by the MTT assay. By three criteria (transmission electron microscopy, DNA electrophoresis and reactivity with annexin V) infected cells exhibited features of apoptosis. Treatment of infected cells with anti-oxidants (catalase, tocopherol and N -acetyl-L-cysteine) significantly decreased the percentage of cell death. In contrast, treatment with aminoguanidine, an inhibitor of inducible NO synthase, increased significantly the killing of PAO-1 infected cells. Based on these results we speculate that in response to P. aeruginosa infection, endothelial cells increase the production of reactive oxygen intermediates to eliminate IC pathogens, but cells do not resist the oxidative stress and die by apoptosis.
Assuntos
Apoptose/fisiologia , Endotélio/microbiologia , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/patogenicidade , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Catalase/farmacologia , Linhagem Celular , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Ágar , Endotélio/citologia , Citometria de Fluxo , Corantes Fluorescentes/química , Formazans/química , Guanidinas/farmacologia , Humanos , Lipopolissacarídeos , Microscopia Eletrônica , Microscopia de Fluorescência , Fenantridinas/química , Pseudomonas aeruginosa/química , Pseudomonas aeruginosa/genética , Espécies Reativas de Oxigênio/fisiologia , Sais de Tetrazólio/química , Vitamina E/farmacologiaRESUMO
The in vitro production of interferon (IFN)-gamma, interleukin (IL)-5, tumour necrosis factor (TNF)-alpha and IL-10 by blood mononuclear cells in response to whole Mycobacterium leprae and polyclonal stimulii of 23 individuals, representing a variety of conditions in relation to exposure/susceptibility to M. leprae, was assayed. In most cases, healthy household contacts of newly diagnosed multibacillary leprosy patients, designated exposed household contacts (EC), showed low-to-undetectable in vitro IFN-gamma production in addition to substantial TNF-alpha production in response to M. leprae. In contrast, peripheral blood mononuclear cells from previously exposed contacts (R) regarded as resistant-to-leprosy released low-to-moderate levels of IFN-gamma together with a mixed cytokine profile resembling a T helper (Th)0-type response. TNF-alpha/IL-10 ratios in response to M. leprae and Concanavalin A were significantly higher in EC than in R contacts suggesting a role for the TNF-alpha/IL-10 ratio in restraining mycobacteria proliferation and spreading early in infection. The cytokine profiles of leprosy patients were taken as reference points. Post-treatment lepromatous leprosy patients secreted relatively high levels of IL-10 in response to M. leprae, whereas one self-cured tuberculoid leprosy patient produced simultaneously high levels of IFN-gamma and TNF-alpha. In addition, the quantitative changes in the cytokines released by peripheral blood mononuclear cells in EC contacts after Bacille Calmette-Guérin (BCG) vaccination were investigated. Vaccination induced amplification of IFN-gamma production with a concomitant decrease in TNF-alpha/IL-10 ratios that resembled the cytokine pattern observed in R contacts. IFN-gamma production was observed in response to both a cross-reactive antigen (Ag 85) and a M. leprae-specific protein (MMP-I), which attests to a BCG nonspecific stimulation of the immune system, thereby casting these antigens as likely candidates for inclusion in a subunit vaccine against leprosy. Finally, a model for protective x pathologic response to mycobacteria is presented.
Assuntos
Interferon gama/biossíntese , Interleucina-10/biossíntese , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Adolescente , Adulto , Idoso , Vacina BCG/administração & dosagem , Criança , Humanos , Imunidade , Hanseníase/transmissão , Hanseníase Virchowiana/imunologia , Hanseníase Tuberculoide/imunologia , Ativação Linfocitária , Pessoa de Meia-Idade , Testes Cutâneos , VacinaçãoAssuntos
Adolescente , Ativação Linfocitária , Criança , Fator de Necrose Tumoral alfa , Hanseníase Tuberculoide/imunologia , Hanseníase Virchowiana/imunologia , Hanseníase/imunologia , Hanseníase/transmissão , Imunidade , Interferon gama/biossíntese , /biossíntese , Linfócitos T/imunologia , Mycobacterium leprae/imunologia , Testes Cutâneos , Vacina BCG/administração & dosagem , VacinaçãoRESUMO
The aim of this study was to identify the nursing care needs of patients of critical care unit. The nursing diagnoses of 32 patients was formulated. The data was collected by interview and physical examination and the Functional Health Patterns was the framework to collect the data and to identify the predominant dysfunctional health areas.