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1.
BMJ Open ; 14(3): e080374, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38503408

RESUMO

OBJECTIVE: Health system leadership plays a critical role in sustaining healthcare delivery during emergencies. Thus, we aimed to assess the contribution of health system leadership in sustaining healthcare delivery under emergency conditions based on adaptive leadership theoretical framework. DESIGN: We employed a concurrent mixed-methods study approach to assess health system leadership roles during emergency. This involved a quantitative survey administered to 150 health facilities managers/service focal persons selected via multistage sampling method from 15 districts, and qualitative interviews with 48 key informants who purposively selected. PARTICIPANTS: We interviewed health facility managers, services focal persons, district health officers and residential district commissioners. We also reviewed weekly emergency situation reports and other relevant documents related to the emergency response. We used structured questionnaire, observation checklist and semistructured questionnaire to collect data. We employed descriptive statistics to analyse quantitative data and thematic analysis for qualitative data. MAIN OUTCOME: Health system leadership contributions in sustaining healthcare delivery during emergencies. RESULTS: Health system leadership was effective in leading emergency response and ensuring the continuity of health service during emergencies. Community engagement, partners coordination and intersectoral collaboration were effectively used in the emergency response and ensuring continuity of healthcare delivery. Deployment of experienced personnel and essential medical and non-medical supplies played a critical role in the continuity of health service. Availability of incidence management teams across health system significantly contributed to health system leadership. Participation of village health teams in community engagement and information communication helped in the success of health system leadership under emergency. CONCLUSION: Adaptive health system leadership played a crucial role in managing health services delivery under emergency conditions. Effective partnership coordination and collaboration across sectors, frequent information communication, building local actor capacity and implementing scheduled supportive supervisions emerged as key strategies for sustaining health services during emergencies.


Assuntos
Emergências , Liderança , Humanos , Secas , Uganda , Atenção à Saúde
2.
J Nanosci Nanotechnol ; 6(9-10): 3261-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17048545

RESUMO

PVA coated and fluorescent dye (Cy3.5) functionalized vinyl alcohol/vinyl amine copolymer coated superparamagnetic iron oxide nanoparticles (SPION) were evaluated for systemic distribution and elimination after intraarticular injection in sheep. Observation was done at 3, 24, 72, and 120 hours after injection using light microscopy, fluorescent microscopy, and confocal microscopy. No pathologic influence of SPION on the tissue harvested could be seen. A significantly increased iron content could be identified in the kidneys, lymph nodes, and spleen after injection of SPION. No particles were detected in the liver, the urinary, and the gall bladder. No positive fluorescent signal could be attributed to SPION throughout the organs. Our results indicated that the iron component of the SPION is possible to be incorporated into the physiologic iron metabolism after reabsorption in the proximal tubule system of the kidney and that concentration levels of Cy3.5 are too low to be detected throughout the body.


Assuntos
Carbocianinas , Óxido Ferroso-Férrico/farmacocinética , Nanoestruturas/química , Álcool de Polivinil/química , Animais , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/farmacocinética , Óxido Ferroso-Férrico/administração & dosagem , Injeções Intra-Articulares , Taxa de Depuração Metabólica , Nanoestruturas/ultraestrutura , Especificidade de Órgãos , Ovinos , Distribuição Tecidual
3.
J Nanosci Nanotechnol ; 6(9-10): 2829-40, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17048489

RESUMO

Superparamagnetic iron oxide nanoparticles (SPION) were coated with either Polyvinyl alcohol (PVA) or Vinyl alcohol/vinyl amine copolymer and further functionalized with the fluorochromes Cy3.5 or Texas Red. A colloidally stable suspension of nanoparticles was incubated on sheep synovial cells in vitro for 3, 24, 72, and 120 hours. Nanoparticle internalization into synoviocytes as well as biocompatibility was visualized using light, fluorescence and confocal microscopy and fluorochrome labeled cells were quantified by flow cytometry. Data were analyzed by ANOVA factorial tests. Amino-PVA-SPION alone was detectable in cytoplasmic endosome-like structures after 3 hours of incubation but resulted in early cell death after 24 hours. Although amino-PVA-Cy3.5-SPION and PVA-TexasRed-SPION were taken up more slowly and less intensely, both labeled more than 80% of the cells in culture, but did not significantly change cell morphology or vitality at any time of evaluation in comparison to control cells. Results indicate that functionalized amino PVA-coated SPION are biocompatible, were successfully internalized by synoviocytes and hold promise for future biomedical applications utilizing magnetic drug targeting in joint disease.


Assuntos
Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Óxido Ferroso-Férrico/química , Nanopartículas/química , Álcool de Polivinil/química , Membrana Sinovial/metabolismo , Animais , Células Cultivadas , Materiais Revestidos Biocompatíveis/administração & dosagem , Magnetismo , Teste de Materiais , Nanopartículas/ultraestrutura , Tamanho da Partícula , Álcool de Polivinil/farmacologia , Ovinos , Membrana Sinovial/efeitos dos fármacos
4.
J Nanosci Nanotechnol ; 6(9-10): 2841-52, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17048490

RESUMO

This study evaluated in vivo gene delivery and subsequent gene expression within cells of the synovium in the presence of static and pulsating magnetic field application following intraarticular injection of superparamagnetic iron oxide nanoparticles linked to plasmids containing reporter genes encoding for fluorescent proteins. Plasmids encoding genes for either green fluorescent protein or red fluorescent protein were bound to superparamagnetic nanoparticles coated with polyethyleneimine. Larger (200-250 nm) and smaller (50 nm) nanoparticles were compared to evaluate the effects of size on transfection efficiency as well as any associated intraarticular reaction. Comparisons between groups were evaluated at 24, 72, and 120 h time periods. Inflammatory response was mild to moderate for all injected particles, but was present in the majority of synovial membrane samples evaluated. Larger particles tended to be associated with more inflammation than smaller ones. Nevertheless, intraarticular application of both experimental and control nanoparticles were well tolerated clinically. Gene expression as determined by observation of either green or red intracellular fluorescence was difficult to assess by both epifluorescent light, and confocal microscopy. An insufficient concentration of nanoparticles in relation to joint volume likely resulted in a limited number of samples with positive evidence of iron staining and with suspected positive evidence of cells expressing fluorescent proteins. Our results indicate that intraarticular administration of functionalized superparamagnetic iron oxide nanoparticles resulted in a mild to moderate synovitis and there was in conclusive evidence of gene expression. Further research is warranted to determine the best and most effective reporter assay for assessment of the in vivo gene delivery into the joints. In addition, the best suited concentration and size of nanoparticles, which will optimize gene delivery and expression, while minimizing intraarticular inflammation, needs to be determined.


Assuntos
Óxido Ferroso-Férrico/química , Nanoestruturas/química , Plasmídeos/administração & dosagem , Plasmídeos/genética , Membrana Sinovial/fisiologia , Transfecção/métodos , Animais , Células Cultivadas , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Expressão Gênica/genética , Injeções Intra-Articulares , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Ovinos
5.
Nucleic Acids Res ; 34(5): e40, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16540591

RESUMO

New approaches to increase the efficiency of non-viral gene delivery are still required. Here we report a simple approach that enhances gene delivery using permanent and pulsating magnetic fields. DNA plasmids and novel DNA fragments (PCR products) containing sequence encoding for green fluorescent protein were coupled to polyethylenimine coated superparamagnetic nanoparticles (SPIONs). The complexes were added to cells that were subsequently exposed to permanent and pulsating magnetic fields. Presence of these magnetic fields significantly increased the transfection efficiency 40 times more than in cells not exposed to the magnetic field. The transfection efficiency was highest when the nanoparticles were sedimented on the permanent magnet before the application of the pulsating field, both for small (50 nm) and large (200-250 nm) nanoparticles. The highly efficient gene transfer already within 5 min shows that this technique is a powerful tool for future in vivo studies, where rapid gene delivery is required before systemic clearance or filtration of the gene vectors occurs.


Assuntos
Magnetismo , Transfecção/métodos , Animais , Compostos Férricos/química , Proteínas de Fluorescência Verde/genética , Humanos , Nanoestruturas/química , Periodicidade , Plasmídeos , Polietilenoimina/química , Reação em Cadeia da Polimerase , Vírus/genética
6.
In Vitro Cell Dev Biol Anim ; 41(7): 207-16, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16223335

RESUMO

Multidrug resistance (MDR) is a major obstacle in cancer therapy. It results from different mechanisms; among them is P-glycoprotein (P-gp)-mediated drug efflux out of cells. The mechanism of action remains elusive. The membrane lipid surrounding of P-gp, especially cholesterol, has been postulated to play an important role. To determine the effect of cholesterol depletion on P-gp, Madin Darby canine kidney (MDCK) cells, transfected with the mdr1 gene (MDR1-MDCK cells), were treated with methyl-beta-cyclodextrin (MbetaCD). The localization and function of P-gp were analyzed using confocal laser scanning microscopy. Treatment with 100 mM MbetaCD did not affect viability but altered the structural appearance of the cells and abolished efflux of rhodamine 123, a P-gp substrate. The MbetaCD treatment released P-gp from intact cells into the supernatant and reduced the amount of P-gp in total membrane preparations. The P-gp was shifted from the raft fractions (1% Triton X-100, 4 degrees C) to higher density fractions in MbetaCD-treated cells. The amount of cholesterol was significantly decreased in the raft fractions. Treatment of cells with 1-phenyl-2-decanoylamino-3-morpholino-1-propanol, a glucosylceramide synthase inhibitor, also led to a shift of P-gp to higher density fractions. These results show that removal of cholesterol modulates the membrane lipid composition, changes the localization of P-gp, and results in loss of P-gp function.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membrana Celular/química , Rim/citologia , Lipídeos de Membrana/química , Animais , Antineoplásicos/farmacologia , Caveolinas/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular , Colesterol/metabolismo , Cães , Resistência a Múltiplos Medicamentos , Corantes Fluorescentes/metabolismo , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo , Proteínas de Membrana/metabolismo , Morfolinas/farmacologia , Ocludina , Rodamina 123/metabolismo , beta-Ciclodextrinas/farmacologia
7.
Pharm Res ; 22(3): 449-57, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15835751

RESUMO

PURPOSE: P-glycoprotein (P-gp), a membrane ATPase expelling many structurally unrelated compounds out of cells, is one of the major contributors to multidrug resistance. It is enriched in cold TritonX-100 insoluble membrane domains (i.e., rafts). The purpose of this work was to characterize the ATPase activities of raft preparations from P388 cells overexpressing P-gp (P388/ADR) or devoid of P-gp (P388) and to establish a P-gp-enriched screening system for P-gp-interfering compounds. METHODS: Rafts were extracted with cold TritonX-100. The ATPase activity was characterized in 96-well plates using a fluorescence assay. RESULTS: The ATPase activity per mg protein was about five times higher in P388/ADR rafts than in crude membranes. The anti-P-gp antibody C219 inhibited 20% of the activity in P388/ADR rafts but only about 10% of the activity in P388/ADR crude membranes and had no effect on the activity of P388 rafts. The known P-gp-activating compounds verapamil, progesterone, and valinomycin revealed the typical bell-shaped activity/concentration profiles in P388/ADR rafts, indicative for activation at low compound concentrations and inhibition at concentrations >10 to 100 microM. The inhibitory effect was also observed in P388 rafts. CONCLUSIONS: Extracted rafts are rich in functional ATPases. Rafts from P-gp-overexpressing cells display P-gp-typical ATPase activity and provide an easy, P-gp-enriched screening system.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adenosina Trifosfatases/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia P388/enzimologia , Microdomínios da Membrana/enzimologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Adenosina Trifosfatases/análise , Animais , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/fisiologia , Inibidores Enzimáticos/farmacologia , Microdomínios da Membrana/química , Microdomínios da Membrana/efeitos dos fármacos , Camundongos
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