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1.
Osteoarthritis Cartilage ; 28(8): 1007-1019, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32445666

RESUMO

OBJECTIVE: In previous research the use of hydrostatic pressure (HP) has been applied to enhance the formation of engineered cartilage, through the up-regulation of proteoglycan synthesis by mechanotransduction. However, the HP stimulation approach has been shown to vary between studies with a wide disparity in results, including anabolic, catabolic and non-responsive outcomes. To this end, a meta-analysis of HP publications using 3D cultured chondrocytes was performed to elucidate the key experiment factors involved in achieving a mechanotransducive response. DESIGN: The effects of different HP regimes on proteoglycan production were investigated based on the following factors: static vs dynamic application, pressure magnitude, and experiment duration. Meta-analysis was performed on raw data taken from 11 publications which employed either aggrecan gene expression analysis or dimethyl methylene blue colorimetric assay. The measure of effect was calculated based on mean difference using a random effects model. RESULTS: Analysis revealed that a significant anabolic response was most likely achieved when the following factors were employed; a static HP application, a magnitude within the mid-high physiological range of cartilage (≤5-10 MPa) and a study duration of ≥2 weeks. CONCLUSIONS: Thus, we propose that the selection of HP experiment factors can have a significant influence on engineered cartilage development, and that the results of this meta-analysis can be used as a basis for the planning of future HP experiments.


Assuntos
Cartilagem Articular , Condrócitos , Pressão Hidrostática , Proteoglicanas/biossíntese , Engenharia Tecidual/métodos , Agrecanas/metabolismo , Animais , Condrogênese , Técnicas de Cultura , Glicosaminoglicanos/metabolismo , Humanos , Técnicas In Vitro , Mecanotransdução Celular , Regulação para Cima
2.
ScientificWorldJournal ; 2014: 505843, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24592172

RESUMO

BACKGROUND: The goal of this retrospective cohort study (REVATA) was to determine the site, source, and contributory factors of varicose vein recurrence after radiofrequency (RF) and laser ablation. METHODS: Seven centers enrolled patients into the study over a 1-year period. All patients underwent previous thermal ablation of the great saphenous vein (GSV), small saphenous vein (SSV), or anterior accessory great saphenous vein (AAGSV). From a specific designed study tool, the etiology of recurrence was identified. RESULTS: 2,380 patients were evaluated during this time frame. A total of 164 patients had varicose vein recurrence at a median of 3 years. GSV ablation was the initial treatment in 159 patients (RF: 33, laser: 126, 52 of these patients had either SSV or AAGSV ablation concurrently). Total or partial GSV recanalization occurred in 47 patients. New AAGSV reflux occurred in 40 patients, and new SSV reflux occurred in 24 patients. Perforator pathology was present in 64% of patients. CONCLUSION: Recurrence of varicose veins occurred at a median of 3 years after procedure. The four most important factors associated with recurrent veins included perforating veins, recanalized GSV, new AAGSV reflux, and new SSV reflux in decreasing frequency. Patients who underwent RF treatment had a statistically higher rate of recanalization than those treated with laser.


Assuntos
Terapia a Laser/métodos , Varizes/cirurgia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Recidiva , Estudos Retrospectivos , Veia Safena/patologia , Veia Safena/cirurgia , Varizes/diagnóstico , Varizes/epidemiologia
3.
J Wound Care ; 22(10 Suppl): S20-2, 2013 10.
Artigo em Inglês | MEDLINE | ID: mdl-24142137

RESUMO

The technique of foam sclerotherapy directed at the distal most vessels, draining the ulcer bed was first described in 2010, with excellent penetration into the underlying venous network possible with this technique. Thirty-five patients have now been treated with this technique as the initial treatment at Midwest Vein Laser, USA. There have been no complications with this technique and rapid healing occurred within 4-8 weeks after the initial treatment in 90% of the patients, and all ulcers were healed at 4 months. Here we present the representative case of a 67-year-old man treated with a modified technique that used a percutaneous approach via reticular or spider veins at the margin of the ulcer bed.


Assuntos
Escleroterapia , Úlcera Varicosa/terapia , Idoso , Humanos , Masculino , Soluções Esclerosantes/administração & dosagem , Escleroterapia/métodos , Tetradecilsulfato de Sódio/administração & dosagem , Cicatrização
4.
Eur Cell Mater ; 19: 214-27, 2010 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-20473830

RESUMO

The remarkable increase in chondrocyte volume is a major determinant in the longitudinal growth of mammalian bones. To permit a detailed morphological study of hypertrophic chondrocytes using standard histological techniques, the preservation of normal chondrocyte morphology is essential. We noticed that during fixation of growth plates with conventional fixative solutions, there was a marked morphological (shrinkage) artifact, and we postulated that this arose from the hyper-osmotic nature of these solutions. To test this, we fixed proximal tibia growth plates of 7-day-old rat bones in either (a) paraformaldehyde (PFA; 4%), (b) glutaraldehyde (GA; 2%) with PFA (2%) with ruthenium hexamine trichloride (RHT; 0.7%), (c) GA (2%) with RHT (0.7%), or (d) GA (1.3%) with RHT (0.5%) and osmolarity adjusted to a 'physiological' level of approximately 280mOsm. Using conventional histological methods, confocal microscopy, and image analysis on fluorescently-labelled fixed and living chondrocytes, we then quantified the extent of cell shrinkage and volume change. Our data showed that the high osmolarity of conventional fixatives caused a shrinkage artefact to chondrocytes. This was particularly evident when whole bones were fixed, but could be markedly reduced if bones were sagittally bisected prior to fixation. The shrinkage artefact could be avoided by adjusting the osmolarity of the fixatives to the osmotic pressure of normal extracellular fluids ( approximately 280mOsm). These results emphasize the importance of fixative osmolarity, in order to accurately preserve the normal volume/morphology of cells within tissues.


Assuntos
Artefatos , Condrócitos/citologia , Fixadores/efeitos adversos , Animais , Tamanho Celular , Condrócitos/efeitos dos fármacos , Lâmina de Crescimento , Concentração Osmolar , Ratos
5.
Eval Program Plann ; 73: 116-128, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30583063

RESUMO

Within the health sciences, organizational participatory research (OPR) is defined as a blend of research and action, in which academic researchers partner with health organization members. OPR is based on a sound partnership between all stakeholders to improve organizational practices. However, little research on the evaluation of OPR health partnership exists. This systematic mixed studies review sought to produce a new theoretical model that structures the evaluation of the OPR processes and related outcomes of OPR health partnerships. Six bibliographic databases were searched together with grey literature sources for OPR health partnership evaluation questionnaires. Six questionnaires were included, from which a pool of 95 OPR health partnership evaluation items were derived. The included questionnaires were appraised for the quality of their origin, development and measurement properties. A framework synthesis was performed using an existing OPR framework by organizing questionnaire items in a matrix using a hybrid thematic analysis. This led to our proposed Organizational Participatory Research Evaluation Model (OPREM) that includes three axes, Trust, Collective Learning and Sustainability (with specific dimensions) and 95 items. This model provides information to help stakeholders comprehensively structure the evaluation of their partnerships and subsequent improvement; thus, potentially helping to improve health organization practices.


Assuntos
Pesquisa Participativa Baseada na Comunidade/organização & administração , Relações Comunidade-Instituição , Pesquisa sobre Serviços de Saúde/organização & administração , Comportamento Cooperativo , Humanos , Aprendizagem , Modelos Organizacionais , Modelos Teóricos , Avaliação de Programas e Projetos de Saúde , Confiança
6.
Eval Program Plann ; 66: 79-88, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29053984

RESUMO

This mixed methods study content validated the Information Assessment Method for parents (IAM-parent) that allows users to systematically rate and comment on online parenting information. Quantitative data and results: 22,407 IAM ratings were collected; of the initial 32 items, descriptive statistics showed that 10 had low relevance. Qualitative data and results: IAM-based comments were collected, and 20 IAM users were interviewed (maximum variation sample); the qualitative data analysis assessed the representativeness of IAM items, and identified items with problematic wording. Researchers, the program director, and Web editors integrated quantitative and qualitative results, which led to a shorter and clearer IAM-parent.


Assuntos
Pais/educação , Avaliação de Programas e Projetos de Saúde/métodos , Avaliação de Programas e Projetos de Saúde/normas , Adulto , Feminino , Humanos , Internet , Masculino , Psicometria , Pesquisa Qualitativa , Reprodutibilidade dos Testes
7.
J Dent Res ; 85(4): 359-63, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16567559

RESUMO

Although enamel demineralization is important for our understanding of caries formation, no consensus has been reached regarding the possible differences in susceptibility of primary and permanent enamel. We used the constant composition (CC) technique to investigate the acid-induced demineralization of these tissues at a relative undersaturation with respect to hydroxyapatite (HAP) of 0.902, pH = 4.5, and ionic strength = 0.15 mol L(-1). The demineralization rates showed significant differences, primary enamel having the greater susceptibility to dissolution during an initial linear stage: 1.5 +/- 0.5 x 10(-10) mol mm(-2) min(-1) compared with 2.6 +/- 0.5 x 10(-11) mol mm(-2) min(-1) for permanent enamel. During the reactions, we observed nanosized crystallites which attached to the enamel surfaces or escaped into the bulk solution. These nanosized crystallites were kinetically protected against further dissolution, even though the solutions remained undersaturated. It is hypothesized that they may contribute to the remarkable mechanical and dynamic characteristics of enamel.


Assuntos
Solubilidade do Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/fisiopatologia , Hidroxiapatitas/análise , Desmineralização do Dente/fisiopatologia , Adulto , Algoritmos , Criança , Cristalografia , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/ultraestrutura , Dentição Permanente , Humanos , Ácido Clorídrico/química , Ácido Clorídrico/farmacologia , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Cinética , Dente Molar/química , Dente Molar/efeitos dos fármacos , Dente Molar/ultraestrutura , Concentração Osmolar , Tamanho da Partícula , Dente Decíduo
8.
J Bone Joint Surg Am ; 87(2): 351-60, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15687159

RESUMO

BACKGROUND: Autologous osteochondral transfer is an option for the treatment of articular defects. However, there are concerns about graft integration and the nature of the tissue forming the cartilage-cartilage bridge. Chondrocyte viability at graft and recipient edges is thought to be an important determinant of the quality of repair. The purpose of the present study was to evaluate early cell viability at the edges of osteochondral grafts from ex vivo human femoral condyles. METHODS: Fresh human tissue was obtained from eleven knees at the time of total knee arthroplasty for the treatment of osteoarthritis. Osteochondral cylinders were harvested with use of a 4.5-mm-diameter mosaicplasty osteotome from regions of the anterolateral aspect of the femoral condyle that were macroscopically nondegenerate and histologically nonfibrillated. Plugs were assessed for marginal cell viability by means of confocal laser scanning microscopy. RESULTS: The diameter of the cartilaginous portion of the osteochondral plugs was a mean (and standard error of the mean) of 4.84 +/- 0.12 mm (as determined on the basis of three plugs). This value was approximately 300 microm greater than the measured internal diameter of the osteotome. There was a substantial margin of superficial zone cell death (mean thickness, 382 +/- 68.2 microm), with >99% cell viability seen more centrally (as determined on the basis of five plugs). Demiplugs were created by splitting the mosaicplasty explants with a fresh number-11 scalpel blade. The margin of superficial zone cell death at the curved edge was significantly greater than that at the site of the scalpel cut (390.3 +/- 18.8 microm compared with 34.8 +/- 3.2 microm; p = 0.0286). Similar findings were observed when the cartilage alone was breached and the bone was left intact, with the margin of superficial zone cell death being significantly greater than that obtained in association with the straight scalpel incision (268 +/- 38.9 microm compared with 41.3 +/- 13.4 microm; p = 0.0286). The margin of superficial zone cell death showed no increase during the time-period between fifteen minutes and two hours after plug harvest. A mathematical approximation of the mosaicplasty region suggested that early cell death of this magnitude affects about one third of the superficial graft area. CONCLUSIONS: The results of the present study suggest that mosaicplasty, while capable of transposing viable hyaline cartilage, is associated with an extensive margin of cell death that is likely to compromise lateral integration and articular reconstruction.


Assuntos
Cartilagem Articular/ultraestrutura , Condrócitos/fisiologia , Fêmur/ultraestrutura , Coleta de Tecidos e Órgãos/métodos , Idoso , Cartilagem Articular/transplante , Morte Celular , Sobrevivência Celular , Condrócitos/ultraestrutura , Fêmur/transplante , Humanos , Microscopia Confocal , Microscopia de Fluorescência , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia
9.
J Med Chem ; 28(6): 828-30, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-4009606

RESUMO

Three potent competitive inhibitors of mammalian liver glyoxalase II, the S-(o-, m-, and p-nitrocarbobenzoxy)-glutathiones, have been synthesized and studied. The Ki values of the ortho, meta, and para isomers, as inhibitors of rat liver glyoxalase II, were 15, 9, and 6.5 microM, respectively. While showing marked competitive inhibition of glyoxalase II, the glutathione derivatives were almost inactive as inhibitors of glyoxalase I. For example, with the para isomer, [I]0.5 values for rat liver glyoxalase I and II were 925 and 12 microM, respectively. This is in marked contrast to other glyoxalase II competitive inhibitors, which in general are even more effective against glyoxalase I. The S-(o-, m-, and p-nitrocarbobenzoxy)glutathiones have found utility as affinity ligands for the purification of rat liver glyoxalase II and may well have use in the study of the glyoxalase enzymes in vivo.


Assuntos
Glutationa/análogos & derivados , Tioléster Hidrolases/antagonistas & inibidores , Animais , Inibidores Enzimáticos/síntese química , Glutationa/síntese química , Glutationa/farmacologia , Cinética , Fígado/enzimologia , Ratos
10.
Placenta ; 24(5): 501-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12744926

RESUMO

Smoking during pregnancy perturbs maternal haemostasis via activated coagulation which could include greater coagulation (fibrin-type fibrinoid deposition) in the placental intervillous space. This might affect intervillous haemodynamics and transport of oxygen and nutrients to the fetus. Fibrin deposits could influence the sizes and numbers of intervillous spaces ('pores') and perivillous fibrin could reflect changes in the nature or activity of trophoblast. Here, we test whether or not smoking is associated with differences in the composition of villous trophoblast, the amounts and patterns of fibrin and, hence, the dimensions and numbers of intervillous pores. Random samples of placentae were taken from pregnancies classified according to smoking status (non-smokers, light smokers, heavy smokers). Stereology was used to estimate volumes of intervillous space and fibrin, test for differences in trophoblast composition and patterns of fibrin deposition at the villous surface, and determine the impact of deposits on the mean volumes and theoretical numbers of intervillous pores. No group differences were found in total volumes or surfaces of trophoblast or total volume of intervillous fibrin. However, the total surfaces of syncytial knots declined in smokers and the surfaces of syncytial bridges increased. Particularly in heavy smokers, this was associated with reduced deposits of perivillous fibrin at syncytial knots. In all placentae, the greatest deposits occurred where there was trophoblast denudation. Little fibrin was seen on thin regions of syncytium. Regardless of smoking status, intervillous fibrin reduced intervillous pore size and increased pore number. However, heavy smokers had larger pores. Reductions in syncytial knots are consistent with reports that smoking reduces the incidence of trophoblast apoptosis whilst increases in syncytial bridges are consistent with enhanced branching angiogenesis. Results confirm that perivillous fibrin accumulates preferentially at denudation sites. They also suggest that smoking perturbs the normal pattern of fibrin deposition, that the impact is greater in heavy smokers and that the placental site is privileged or active in terms of fibrinolytic or anti-coagulatory activity. This activity seems to reside in thin regions of syncytium.


Assuntos
Vilosidades Coriônicas/metabolismo , Fibrina/metabolismo , Exposição Materna/efeitos adversos , Fumar/efeitos adversos , Trofoblastos/metabolismo , Adulto , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/patologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Gravidez , Trofoblastos/efeitos dos fármacos , Trofoblastos/patologia
11.
Placenta ; 19(5-6): 409-15, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9699962

RESUMO

The aim of this study was to investigate location and the types of membrane-associated and cytoplasmic fatty acid-binding proteins in human placental trophoblasts using monospecific polyclonal antibodies. Western blot analysis demonstrated the presence of multiple membrane and cytoplasmic fatty acid transport/binding proteins in human placenta. In addition to previously reported placental membrane fatty acid-binding (p-FABPpm, 40 kDa), fatty acid translocase (FAT, 88 kDa) and fatty acid transport protein (FATP, 62 kDa) were detected in both microvillous and basal membranes of the human placenta. Among the cytoplasmic proteins, heart (H) and liver (L) type FABP were detected in the cytosol of the human placental primary trophoblasts as well as in human placental choriocarcinoma (BeWo) cells. The immunoreactivity of epidermal type (E)-FABP was not detected in trophoblasts or BeWo cells despite its presence in human placental cytosol. Location of FAT and FATP on the both sides of the bipolar placental cells may favour transport of free fatty acids (FFA) pool in both directions i.e. from the mother to the fetus and vice versa. However, p-FABPpm, because of its exclusive location on the microvillous membranes, may favour the unidirectional flow of maternal plasma long-chain polyunsaturated fatty acids present in the FFA pool to the fetus, due to binding specificity for these fatty acids. Although the roles of these proteins in placental fatty acid uptake and metabolism are yet to be understood fully, their complex interaction may be involved in the uptake of maternal FFA by the placenta for delivery to the fetus.


Assuntos
Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Ácidos Graxos/metabolismo , Proteína P2 de Mielina/metabolismo , Proteínas de Neoplasias , Trofoblastos/metabolismo , Proteínas Supressoras de Tumor , Adulto , Western Blotting , Proteínas de Transporte/imunologia , Coriocarcinoma/metabolismo , Citosol/metabolismo , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Ácidos Graxos/imunologia , Feminino , Humanos , Proteína P2 de Mielina/imunologia , Gravidez , Trofoblastos/citologia , Células Tumorais Cultivadas
12.
Placenta ; 21(2-3): 247-56, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10736249

RESUMO

The aim of this study was to quantify the effects of maternal cigarette smoking on placental morphology, paying particular attention to variables known to be influential in facilitating oxygen diffusion. Structural quantities were estimated by stereological analyses of placental samples drawn from non-smoking and smoking women whose smoking habits were assessed both subjectively (from volunteered cigarette consumption) and objectively (by determining levels of plasma cotinine, a major metabolite of nicotine). Concentrations of placental cadmium were also measured. In the smoking group, maternal and fetal haematocrits were elevated and mean birthweight was reduced. Within placentae, the most significant alterations were increases in cadmium levels, the relative volumes of maternal intervillous space, the relative surface areas of fetal capillaries and decreases in the relative and absolute volumes of fetal capillaries. Findings indicate that changes in capillary volume are the result of a decrease in mean capillary diameter rather than total length. The mean thickness of the trophoblast component of the villous membrane was also increased in the smoking group. Although increased haematocrits suggest that fetuses of smoking mothers suffer hypoxic stress, these morphological changes are likely to compromise, rather than assist, transplacental oxygen transfer. This is in marked contrast to the adaptive changes seen in pregnancies associated with preplacental hypoxia and suggests that other factors might be compromising the fetoplacental unit. Finally, although the morphological changes associated with maternal smoking seem to be the result of an all-or-none, rather than dose-dependent, effect, the available evidence is not conclusive.


Assuntos
Cádmio/metabolismo , Placenta/metabolismo , Placenta/patologia , Fumar/efeitos adversos , Estudos de Casos e Controles , Cotinina/sangue , Citocromo P-450 CYP1A1/metabolismo , Feminino , Hipóxia Fetal/etiologia , Hipóxia Fetal/metabolismo , Hipóxia Fetal/patologia , Humanos , Gravidez , Fumar/metabolismo , Fumar/patologia
13.
Placenta ; 21(8): 824-33, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11095932

RESUMO

The aim of this study was to test whether or not adaptations in partial, total and specific oxygen diffusive conductances occur in the placentae of women who smoke cigarettes during pregnancy and help to compensate for intrauterine fetal hypoxic stress. Tissue sections were randomly sampled from human term placentae divided into two groups (non-smokers and smokers) according to maternal smoking status. In smokers, status was expressed as either declared smoking rate or level of plasma cotinine (the major metabolite of nicotine). Sections were analysed stereologically to estimate key structural quantities (vascular volumes, exchange surface areas, tissue diffusion distances). These were combined with previously-published physicochemical quantities (oxygen-haemoglobin reaction rates and tissue oxygen diffusion coefficients) in order to estimate the partial conductances of six tissue compartments of the oxygen pathway: maternal erythrocytes and plasma, villous trophoblast, villous stroma (including fetal capillary wall), fetal plasma and erythrocytes. From partial conductances and birthweights, total and specific conductances were calculated for each placenta. Results were assessed statistically by analyses of variance and t -tests. Despite apparent improvements in the partial conductances of the maternal erythrocytes and plasma, total and specific conductances did not alter significantly in smoking groups. However, the relative biases affecting these estimates may be different in smokers and non-smokers. We conclude that total conductance does not increase in placentae associated with maternal smoking. However, given that the fetus suffers chronic hypoxic stress as a consequence of smoking (evidenced here by elevated haematocrits), even a constant diffusive conductance implies a reduced transplacental partial pressure gradient. This could be a contributory factor to the reduced birthweight.


Assuntos
Oxigênio/metabolismo , Placenta/metabolismo , Fumar/efeitos adversos , Adulto , Peso ao Nascer , Fenômenos Químicos , Físico-Química , Cotinina/sangue , Difusão , Feminino , Humanos , Recém-Nascido , Tamanho do Órgão , Oxigênio/química , Placenta/anatomia & histologia , Placenta/irrigação sanguínea , Gravidez
14.
J Thorac Cardiovasc Surg ; 107(3): 838-48; discussion 848-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8127113

RESUMO

Since 1973, 7667 neonates have been treated with extracorporeal membrane oxygenation for severe respiratory failure and their cases reported to the Extracorporeal Life Support Organization Registry. The overall survival was 81% in these neonates, who were thought to have a survival of 20% without extracorporeal membrane oxygenation. A total of 4322 mechanical complications (0.56 +/- 0.84 per case) and 13,827 patient complications (1.80 +/- 2.12 per case) were reported overall. The most common mechanical complications included clots in the circuit (19%), cannula placement (9%), oxygenator failure (4%), and others (9%). Common patient complications included cardiopulmonary (43%), neurologic (35%), bleeding (35%), metabolic (32%), renal (25%), and renal (25%), and infectious (9%). From the initial experience to 1988 the average number of mechanical complications per case was 0.27 per case and this significantly increased during 1990 to 1992 to 0.75 per case (p < 0.05). Likewise, from 1973-1985 to 1988 the average patient complications per case were 1.44 per case and this significantly increased during 1990 to 1992 to 2.10 per case. During the same periods, patient survival significantly decreased from 84% (1973-1985 to 1988, n = 2463) to 80% (1990 to 1992, n = 4005). Venovenous double-lumen single cannula extracorporeal membrane oxygenation had a higher survival than venoarterial extracorporeal membrane oxygenation (91% versus 81%) and a lower rate of major neurologic complications. The incidence and survival with seizures (6% and 89% venovenous versus 13% and 61% venoarterial) or cerebral infarction (9% and 69% venovenous versus 14% and 46% venoarterial) was significantly lower with the venovenous method and appeared to have a substantial impact on overall survival. The correlation of patient complication rate and total complication rate with survival was highly significant, however, causality cannot be established. Explanations for the increase in complications, relative to a decrease in survival, despite a growing nationwide experience include (1) increased complexity of cases as many programs expand entry criteria (more premature infants, infants with grade 1 or 2 intracranial hemorrhage, and complex congenital diaphragmatic hernia), (2) a growing number of programs with fewer cases per program, yet greater accessibility, (3) less reluctance to report complications encountered during extracorporeal membrane oxygenation as group experience grows, and (4) changes in the Extracorporeal Life Support Organization data form to be more inclusive of more minor complications.


Assuntos
Oxigenação por Membrana Extracorpórea/efeitos adversos , Insuficiência Respiratória/terapia , Falha de Equipamento/estatística & dados numéricos , Europa (Continente)/epidemiologia , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/mortalidade , Humanos , Recém-Nascido , Modelos Lineares , Sistema de Registros , Insuficiência Respiratória/mortalidade , Análise de Sobrevida , Taxa de Sobrevida , Estados Unidos/epidemiologia
15.
J Appl Physiol (1985) ; 78(6): 2161-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7665413

RESUMO

There is evidence of increased oxygen free radical activity after smoke inhalation with and without concomitant burn injury. We determined the effects of manganese superoxide dismutase (Mn SOD) on lung fluid balance as measured by lung microvascular permeability coefficient (sigma), filtration coefficient (Kf), and lymph flow. Merino breed ewes (n = 6/group) were surgically prepared. The SOD group (SOD) received Mn SOD (9,000 U/kg) as an intravenous bolus and was insufflated with smoke. The control group (CON) received saline and smoke. sigma and Kf were determined 24 h before and 24 h after smoke injury. Lymph flow, arterial O2-to-inspired O2 fraction ratio, systemic hemodynamics, and pulmonary arterial and capillary pressures were measured. The sigma was significantly (P < 0.05) higher after smoke insufflation in SOD compared with CON (0.71 +/- 0.03 vs. 0.53 +/- 0.05). Kf was significantly lower after smoke insufflation in SOD compared with CON (0.038 +/- 0.010 vs. 0.061 +/- 0.010). Lymph flows were significantly lower during the 24 h after smoke insufflation in SOD compared with CON (33 +/- 7 vs. 55 +/- 8 ml/h at 24 h). Arterial O2-to-inspired O2 fraction ratio was significantly improved at 6 and 12 h after smoke insufflation in SOD compared with CON at the same time points. Mn SOD meliorates the lung microvascular permeability changes associated with smoke inhalation injury.


Assuntos
Pulmão/efeitos dos fármacos , Fumaça/efeitos adversos , Superóxido Dismutase/farmacologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Administração por Inalação , Animais , Hemodinâmica , Lesão Pulmonar , Manganês , Neutrófilos , Oxigênio/metabolismo , Ovinos , Fumar/efeitos adversos , Fatores de Tempo
16.
J Neurosci Methods ; 46(2): 159-66, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8474259

RESUMO

Model neurons composed of hundreds of compartments are currently used for studying phenomena at the level of the single cell. Large network simulations require a simplified model of a single neuron that retains the electrotonic and synaptic integrative properties of the real cell. We introduce a method for reducing the number of compartments of neocortical pyramidal neuron models (from 400 to 8-9 compartments) through a simple collapsing method based on conserving the axial resistance rather than on the surface area of the dendritic tree. The reduced models retain the general morphology of the pyramidal cells on which they are based, allowing accurate positioning of synaptic inputs and ionic conductances on individual model cells, as well as construction of spatially accurate network models. The reduced models run significantly faster than the full models, yet faithfully reproduce their electrical responses.


Assuntos
Córtex Cerebral/fisiologia , Neurônios/fisiologia , Tratos Piramidais/fisiologia , Potenciais de Ação/fisiologia , Animais , Gatos , Córtex Cerebral/citologia , Dendritos/fisiologia , Eletrofisiologia , Peroxidase do Rábano Silvestre , Modelos Neurológicos , Tratos Piramidais/citologia , Sinapses/fisiologia
17.
Clin Ther ; 21(7): 1280-4, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10463524

RESUMO

In 1996, an open conference sponsored by the US Pharmacopeia (USP) and attended by more than 100 health care professionals established the need and rationale for teaching children and adolescents about medicines. After the conference, a public, iterative, consensus-development process including participation by 35 health-professional organizations was undertaken. This process resulted in a USP position statement, "Ten Guiding Principles for Teaching Children and Adolescents About Medicines," which supports the right of children and adolescents to receive developmentally appropriate information and direct communications about medicines that are consistent with their health status, capabilities, and culture. The position statement is intended to stimulate activities that will help children become active participants in the process of appropriate use of medicines and prepare them for the day they begin to use medicines independently.


Assuntos
Educação em Saúde , Preparações Farmacêuticas , Adolescente , Pré-Escolar , Comunicação , Educação em Saúde/métodos , Humanos , Pais , Instituições Acadêmicas , Estados Unidos
18.
J Orthop Res ; 19(5): 768-78, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11562120

RESUMO

Articular chondrocytes experience changes to matrix hydration during both physiological (static load) and pathophysiological (osteoarthrosis, OA) conditions. Such changes should alter chondrocytes' volume, which has been shown to modify matrix metabolism. However, the osmometric behaviour of chondrocytes is not well understood. Here, using confocal laser scanning microscopy (CLSM), we have investigated the 'passive' osmotic responses of fluorescent-labelled chondrocytes within, and isolated from, the matrix. The volume-regulatory pathways normally activated by cell shrinkage/swelling, were blocked by bumetanide/REV5901, respectively. Chondrocytes in situ were broadly grouped into superficial (SZ), mid (MZ) and deep (DZ) zones, and there was a significant increase in resting cell volume with depth into the cartilage. Variation in medium osmolarity (range 0-530 mOsm; corresponding to an extracellular osmolarity of approximately 150 to approximately 600 mOsm) caused a rapid and sustained change to in situ MZ chondrocytes' volume. Over the range 180-380 mOsm, the change to in situ or isolated chondrocytes' volume was similar. For MZ chondrocytes. ideal osmometric (Boyle-van't Hoff) behaviour was apparent over the extracellular osmolarity range of approximately 250 to approximately 600 mOsm. Chondrocytes within the SZ appeared to be more sensitive to reduced osmolarity, swelling more for a given reduction in osmolarity, than MZ or DZ chondrocytes. These data show that over wide variations in osmolarity, articular chondrocytes in situ were osmotically sensitive, and for MZ chondrocytes behaved as perfect osmometers with the extracellular matrix (ECM) not restraining cell volume changes. Changes to matrix hydration may therefore alter passive chondrocytes' volume and unless compensated by volume-regulatory pathways, could lead to changes in cell volume, and hence matrix metabolism.


Assuntos
Cartilagem Articular/citologia , Condrócitos/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Bovinos , Separação Celular , Condrócitos/citologia , Matriz Extracelular/metabolismo , Concentração Osmolar , Pressão Osmótica
19.
Drug Alcohol Depend ; 30(3): 275-87, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1396109

RESUMO

In each of 2 years beginning in fourth and fifth grades, urban elementary public schoolchildren completed surveys about abusable substance use and health promoting behaviors and completed an instrument that permitted each child to have a socialization score attributed by classmates. A factor weighted 12-item scale was developed from 15 items in three domains (personal, interpersonal and school). The scale was positively correlated over the 2 years and positively correlated with a healthful activities scale in both years. Conditional multiple logistic regression, matching on school classroom, indicated that socialization was negatively associated with use of alcohol without parental permission and cigarettes in both years (grades 4-5, grades 5-6) and with use of marijuana in year 1. Socialization measured in year 1 was negatively associated with cigarette use in year 2 and with onset of use from year 1 to year 2. Shyness, a non-socialization scale item, was negatively associated with use of cigarettes in both years and with use of alcohol without permission and use of marijuana in year 2. Being 'good at sports' was an attribute positively associated with alcohol use without permission and cigarette use in year 2. Results suggest that elementary schoolchildren can ascribe social characteristics to their classmates that are associated with and predict health related behaviors.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Fumar Maconha/epidemiologia , Fumar/epidemiologia , Percepção Social , Socialização , Consumo de Bebidas Alcoólicas/etnologia , Criança , District of Columbia , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Fumar Maconha/etnologia , Grupo Associado , Fatores Sexuais , Fumar/etnologia , Inquéritos e Questionários , População Urbana
20.
Health Serv Res ; 33(5 Pt 1): 1285-308, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9865221

RESUMO

OBJECTIVE: To determine the cost-effectiveness of Assertive Community Treatment (ACT) in comparison to Standard Case Management (SCM) for persons with severe mental illness and substance use disorders. DATA SOURCES AND STUDY SETTING: Original data on the effectiveness and social costs of ACT and SCM that were collected between 1989 and 1995. Seven community mental health centers in New Hampshire provided both types of treatment. STUDY DESIGN: Persons with schizophrenia, schizoaffective disorder, or bipolar disorder and a concurrent substance use disorder were randomly assigned to ACT or SCM and followed for three years. The primary variables assessed were substance use, psychiatric symptoms, functioning, quality of life, and social costs. DATA COLLECTION METHODS: Effectiveness data were obtained from interviews at six-month intervals with persons enrolled in treatment and with their service providers. Social cost and service utilization data came from client reports; interviews with informal caregivers; provider information systems and Medicaid claims; law enforcement agencies; courts; and community service providers. PRINCIPAL FINDINGS: Participants in both groups showed significant reductions in substance use over time. Focusing on quality of life and substance use outcomes, ACT and SCM were not significantly different in cost-effectiveness over the entire three-year study period. Longitudinal analyses showed that SCM tended to be more efficient during the first two years but that ACT was significantly more efficient than SCM during the final year of the study. CONCLUSIONS: In an adequately funded system, ACT is not more cost-effective than SCM. However, ACT efficiency appears to improve over time.


Assuntos
Administração de Caso/economia , Centros Comunitários de Saúde Mental/economia , Equipe de Assistência ao Paciente/economia , Transtornos Psicóticos/economia , Transtornos Relacionados ao Uso de Substâncias/economia , Adolescente , Adulto , Comorbidade , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Diagnóstico Duplo (Psiquiatria) , Feminino , Seguimentos , Humanos , Masculino , Medicaid/economia , Pessoa de Meia-Idade , New Hampshire , Transtornos Psicóticos/reabilitação , Qualidade de Vida , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Resultado do Tratamento , Estados Unidos
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