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1.
Braz J Biol ; 84: e279583, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38985060

RESUMEN

We aimed to characterize the adult and regenerating tree components and their relationships with soil characteristics of a native vegetation remnant in Cuiabá, Mato Grosso, Brazil. The area of the fragment is stratified into "dry area" (lithic neosoil) and "damp area" (gleisoil). We conducted a forest inventory with a random distribution of 25 parcels. We analyzed the physical and chemical components of the soil. We evaluated the vegetation's horizontal structure, diversity, and sample sufficiency using the Bootstrap richness estimator. We classified the species according to dispersal syndrome and ecological group. Overall, we found 93 species in the adult layer and 70 species in the regenerating layer. The similarity dendrograms based on the two evaluated indices demonstrated the existence of the two initially stratified environments in both strata. The IndVal (%) indicated that the set of indicator species differed between the strata. Thereby, the fragment is in an intermediate stage of successional progression. PCA showed that plots in the wet area had higher pH values and Ca, Zn, and Fe levels, while plots in the dry area did not clearly distinguish, varying in terms of K, B, and organic matter content. In CCA, a set of species that occurred exclusively in the damp area showed a strong relationship with the analyzed variables. The area is a diverse ecosystem that efficiently provides ecosystem services to society and should be the subject of long-term conservation and research.


Asunto(s)
Biodiversidad , Bosques , Suelo , Brasil , Suelo/química , Árboles/clasificación
2.
J Magn Reson ; 286: 138-142, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29241045

RESUMEN

Recently, it was observed that protons in non-conducting solids doped with 1,3-bisdiphenylene-2-phenylallyl (BDPA) or its sulfonated derivative (SA-BDPA) can be polarized through Overhauser effects via resonant microwave irradiation. These effects were present under magic angle spinning conditions in magnetic fields between 5 and 18.8 T and at temperatures near 100 K. This communication reports similar effects in static samples at 6.7 T and, more importantly, at temperatures as low as 1.2 K, in a different dynamic regime than in the previous study. Our results provide new information towards understanding the mechanism of the Overhauser effect in non-conducting solids. We discuss possible origins of the fluctuations that can give rise to an Overhauser effect at such low temperatures.

3.
Mater Sci Eng C Mater Biol Appl ; 81: 373-379, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28887986

RESUMEN

Recently, the development of coatings to protect biomedical alloys from oxidation, passivation and to reduce the ability for a bacterial biofilm to form after implantation has emerged. Diamond-like carbon films are commonly used for implanted medical due to their physical and chemical characteristics, showing good interactions with the biological environment. However, these properties can be significantly improved when titanium dioxide nanoparticles are included, especially to enhance the bactericidal properties of the films. So far, the deposition of hydroxyapatite on the film surface has been studied in order to improve biocompatibility and bioactive behavior. Herein, we developed a new route to obtain a homogeneous and crystalline apatite coating on diamond-like carbon films grown on 304 biomedical stainless steel and evaluated its antibacterial effect. For this purpose, films containing two different concentrations of titanium dioxide (0.1 and 0.3g/L) were obtained by chemical vapor deposition. To obtain the apatite layer, the samples were soaked in simulated body fluid solution for up to 21days. The antibacterial activity of the films was evaluated by bacterial eradication tests using Staphylococcus aureus biofilm. Scanning electron microscopy, X-ray diffraction, Raman scattering spectroscopy, and goniometry showed that homogeneous, crystalline, and hydrophilic apatite films were formed independently of the titanium dioxide concentration. Interestingly, the diamond-like films containing titanium dioxide and hydroxyapatite reduced the biofilm formation compared to controls. A synergism between hydroxyapatite and titanium dioxide that provided an antimicrobial effect against opportunistic pathogens was clearly observed.


Asunto(s)
Biopelículas , Carbono , Materiales Biocompatibles Revestidos , Diamante , Nanopartículas del Metal , Staphylococcus aureus , Propiedades de Superficie , Titanio
4.
Accid Anal Prev ; 49: 486-92, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22633251

RESUMEN

This study aimed to compare an in-class Seniors on the MOVE (Mature Operators Vehicular Education) interactive multi-session driving curriculum with a self-guided MOVE curriculum for older adults. Using a two group randomized design, we sought to determine if there are between-group differences in older drivers' knowledge and safety behaviors among participants. Forty-four participants with an average age of 79 years (SD=7.1) were randomly assigned to the original MOVE program (SOM-A) or a lower resource (SOM-B) self-guided intervention. SOM-A is a four session program designed to improve older drivers safety knowledge and better understand skills for safer driving. SOM-B is a self-guided program with one required in-class session and one optional session. Subsequent to completion of both curricula, participants were offered CarFit, a comprehensive check of how well a senior driver and their vehicle work together. Baseline, post-intervention and 6-month follow up questionnaires were completed by participants. We found significant differences (p=.01) in the mean driving safety knowledge scores when comparing participants in SOM-A (3.7, SD 2.0) to those in SOM-B (0.87, SD 2.6). With regard to behavioral outcomes, we focused on always wearing a seatbelt, talking with a health care provider about driving ability, and sitting 10-12 inches from the steering wheel. The vast majority of participants reported always wearing their seat belts (SOM-A 100%, SOM-B 92%, p=1.0), and very few reported talking with their doctors (SOM-A Baseline--0%, Follow up 1--0%, p=n/a). Mean behavior change scores for participants sitting 10-12 inches from the steering wheel were significantly more likely among SOM-A (mean=.65, SD=.5) participants than those in SOM-B (mean=.29, SD=.5, p=.01) at first follow-up. Taken together, these findings suggest that the more intensive program is more effective and that driving safety programs focused on behaviors to self evaluate driving abilities continue to be needed to help older drivers remain safer on the road as they age. The involvement of health care providers in such efforts may be an untapped potential.


Asunto(s)
Accidentes de Tránsito/prevención & control , Conducción de Automóvil/educación , Curriculum , Conducta Peligrosa , Conocimientos, Actitudes y Práctica en Salud , Seguridad , Anciano , Anciano de 80 o más Años , Conducción de Automóvil/psicología , Evaluación Educacional , Femenino , Estudios de Seguimiento , Reducción del Daño , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
5.
Braz J Med Biol Res ; 41(9): 818-24, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18820773

RESUMEN

The objective of the present study was to determine to what extent, if any, swimming training applied before immobilization in a cast interferes with the rehabilitation process in rat muscles. Female Wistar rats, mean weight 260.52 +/- 16.26 g, were divided into 4 groups of 6 rats each: control, 6 weeks under baseline conditions; trained, swimming training for 6 weeks; trained-immobilized, swimming training for 6 weeks and then immobilized for 1 week; trained-immobilized-rehabilitated, swimming training for 6 weeks, immobilized for 1 week and then remobilized with swimming for 2 weeks. The animals were then sacrificed and the soleus and tibialis anterior muscles were dissected, frozen in liquid nitrogen and processed histochemically (H&E and mATPase). Data were analyzed statistically by the mixed effects linear model (P < 0.05). Cytoarchitectural changes such as degenerative characteristics in the immobilized group and regenerative characteristics such as centralized nucleus, fiber size variation and cell fragmentation in the groups submitted to swimming were more significant in the soleus muscle. The diameters of the lesser soleus type 1 and type 2A fibers were significantly reduced in the trained-immobilized group compared to the trained group (P < 0.001). In the tibialis anterior, there was an increase in the number of type 2B fibers and a reduction in type 2A fibers when trained-immobilized rats were compared to trained rats (P < 0.001). In trained-immobilized-rehabilitated rats, there was a reduction in type 2B fibers and an increase in type 2A fibers compared to trained-immobilized rats (P < 0.009). We concluded that swimming training did not minimize the deleterious effects of immobilization on the muscles studied and that remobilization did not favor tissue re-adaptation.


Asunto(s)
Inmovilización , Músculo Esquelético/patología , Atrofia Muscular/rehabilitación , Condicionamiento Físico Animal/fisiología , Natación/fisiología , Adaptación Fisiológica , Animales , Femenino , Atrofia Muscular/etiología , Ratas , Ratas Wistar
6.
Braz. j. med. biol. res ; 41(9): 818-824, Sept. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-492879

RESUMEN

The objective of the present study was to determine to what extent, if any, swimming training applied before immobilization in a cast interferes with the rehabilitation process in rat muscles. Female Wistar rats, mean weight 260.52 ± 16.26 g, were divided into 4 groups of 6 rats each: control, 6 weeks under baseline conditions; trained, swimming training for 6 weeks; trained-immobilized, swimming training for 6 weeks and then immobilized for 1 week; trained-immobilized-rehabilitated, swimming training for 6 weeks, immobilized for 1 week and then remobilized with swimming for 2 weeks. The animals were then sacrificed and the soleus and tibialis anterior muscles were dissected, frozen in liquid nitrogen and processed histochemically (H&E and mATPase). Data were analyzed statistically by the mixed effects linear model (P < 0.05). Cytoarchitectural changes such as degenerative characteristics in the immobilized group and regenerative characteristics such as centralized nucleus, fiber size variation and cell fragmentation in the groups submitted to swimming were more significant in the soleus muscle. The diameters of the lesser soleus type 1 and type 2A fibers were significantly reduced in the trained-immobilized group compared to the trained group (P < 0.001). In the tibialis anterior, there was an increase in the number of type 2B fibers and a reduction in type 2A fibers when trained-immobilized rats were compared to trained rats (P < 0.001). In trained-immobilized-rehabilitated rats, there was a reduction in type 2B fibers and an increase in type 2A fibers compared to trained-immobilized rats (P < 0.009). We concluded that swimming training did not minimize the deleterious effects of immobilization on the muscles studied and that remobilization did not favor tissue re-adaptation.


Asunto(s)
Animales , Femenino , Ratas , Inmovilización , Músculo Esquelético/patología , Atrofia Muscular/rehabilitación , Condicionamiento Físico Animal/fisiología , Natación/fisiología , Adaptación Fisiológica , Atrofia Muscular/etiología , Ratas Wistar
7.
Braz. j. phys. ther. (Impr.) ; 12(3): 241-247, maio-jun. 2008. ilus, graf
Artículo en Inglés, Portugués | LILACS | ID: lil-488925

RESUMEN

CONTEXTUALIZAÇÃO: O ultra-som terapêutico (UST) é um recurso comumente aplicado na aceleração do reparo tecidual de lesões musculares. A absorção das ondas ultra-sônicas é determinada pela freqüência e pela intensidade, sendo que, em uma mesma intensidade, a profundidade atingida por 1MHz é maior quando comparada a 3MHz. OBJETIVO: Analisar o comportamento das propriedades mecânicas de músculos submetidos à lesão aguda por impacto e tratados com UST, utilizando as freqüências de 1 e 3MHz. MATERIAIS E MÉTODOS: Foram utilizadas 40 ratas Wistar (200,1±17,8g), divididas em quatro grupos: (1) controle; (2) lesão muscular sem tratamento; (3) lesão muscular tratada com UST de freqüência 1MHz (0,5W/cm²) e (4) lesão muscular tratada com UST de freqüência 3MHz (0,5W/cm²). A lesão foi provocada no músculo gastrocnêmio por mecanismo de impacto. O tratamento foi de cinco minutos diários durante seis dias consecutivos. Os músculos foram submetidos a ensaios mecânicos de tração em uma máquina universal de ensaios. RESULTADOS: As médias e desvios-padrão das propriedades mecânicas dos grupos lesionados e tratados com UST foram significativamente maiores quando comparadas ao grupo lesionado sem tratamento (p<0,05). Em destaque, a propriedade de rigidez que, com a aplicação do UST, teve acréscimo de aproximadamente 38 por cento. CONCLUSÕES: A intervenção, por meio do UST, promoveu aumento das propriedades mecânicas nos músculos lesionados aproximando-as do grupo controle. Entretanto, não foi observada diferença significativa entre as propriedades mecânicas dos grupos tratados com ultra-som de freqüências 1MHz e 3MHz.


BACKGROUND: Therapeutic ultrasound is a resource commonly applied to speed up tissue repair in muscle injuries. The absorption of the ultrasound waves is determined by their frequency and intensity. For a given intensity, the depth reached by 1MHz is greater than the depth reached by 3MHz. OBJECTIVE: To analyze the mechanical properties of muscles subjected to acute impact injury treated with therapeutic ultrasound at the frequencies of 1 and 3MHz. METHODS: Forty female Wistar rats (200.1±17.8g) were used, divided into four groups: (1) control; (2) muscle injury without treatment; (3) muscle injury treated with therapeutic ultrasound at the frequency of 1MHz (0.5W/cm²); and (4) muscle injury treated with therapeutic ultrasound at the frequency of 3MHz (0.5W/cm²). The injury was produced in the gastrocnemius muscle by means of an impact mechanism. The treatment consisted of a single five-minute session per day, for six consecutive days. The muscles were subjected to mechanical traction tests in a universal test machine. RESULTS: Means and standard deviations for the mechanical properties of the injured groups that received therapeutic ultrasound were significantly greater than those of the injured group without treatment (p<0.05). The property of stiffness should be highlighted: the application of therapeutic ultrasound increased muscle stiffness by approximately 38 percent. CONCLUSIONS: Therapeutic ultrasound increased the mechanical properties of the injured muscles, and brought them to a level close to the control group. However, no significant difference in mechanical properties was observed between the groups treated with ultrasound at the frequencies of 1MHz and 3MHz.


Asunto(s)
Ratas , Animales , Modalidades de Fisioterapia , Sistema Musculoesquelético/lesiones , Terapia por Ultrasonido
8.
Eur J Appl Physiol Occup Physiol ; 78(3): 247-52, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9721004

RESUMEN

In this study we investigated possible differences in fibrinolytic activity in cardiac patients while they performed treadmill and cycle ergometry. Thirteen post-myocardial infarction patients completed two maximal exercise tests on treadmill and cycle ergometers. Blood was collected before and after each exercise test and was analyzed for the fibrinolytic variables, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) activity, and lactate. Maximal oxygen uptake, heart rate, and ventilation were greater (P < 0.05) on the treadmill than during cycle ergometry, however, blood lactate was similar between modes. t-PA activity significantly increased with exercise (P < 0.05) and there was a trend toward a reduction in PAI-1 activity with exercise, but this did not reach statistical significance. The fibrinolytic responses to maximal exercise did not differ between the two modes of exercise studied. Therefore, exercise intensity, but not the mode of exercise, appeared to be the primary determinant of the fibrinolytic response to acute exercise in these patients.


Asunto(s)
Ciclismo/fisiología , Ejercicio Físico/fisiología , Fibrinólisis/fisiología , Infarto del Miocardio/fisiopatología , Caminata/fisiología , Prueba de Esfuerzo , Femenino , Hematócrito , Humanos , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad , Infarto del Miocardio/rehabilitación , Consumo de Oxígeno/fisiología , Inhibidor 1 de Activador Plasminogénico/sangre , Activador de Tejido Plasminógeno/sangre
9.
J Cardiopulm Rehabil ; 18(2): 129-38, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9559450

RESUMEN

PURPOSE: This study examined the effect of steady-state on the ability of 15 men with coronary artery disease (CAD) and 13 men without CAD disease (non-CAD) to reach a rate of oxygen consumption (VO2) relative to population norms during treadmill and cycle ergometry exercise testing. METHODS: Subjects completed a maximal graded exercise test on the treadmill and cycle ergometry involving 3-minute stages and a submaximal exercise test involving 6-minute stages to 80% of maximal effort. Estimates of VO2 were derived from commonly cited clinical estimation equations. RESULTS: Only the Foster equation accurately estimated maximal VO2 during a treadmill graded exercise test in patients with CAD. However, each of cited clinical equations accurately estimated maximal VO2 during a treadmill graded exercise test in the non-CAD group. No equation accurately estimated VO2 at submaximal efforts during treadmill exercise for either group. Cycle ergometry estimation equations accurately estimated VO2 in both groups at maximal effort, but were inconsistent at submaximal efforts. Both the CAD and the non-CAD group reached steady-state VO2 within 3 minutes, at submaximal workloads. CONCLUSIONS: The inability to attain an expected VO2 during exercise did not seem related to steady-state VO2 because both CAD and non-CAD groups readily reached steady-state VO2, though the estimation of VO2 remained inaccurate for most treadmill estimation equations. Because VO2 was accurately estimated for cycle ergometry exercise, estimation accuracy seems to be influenced by exercise modality.


Asunto(s)
Enfermedad Coronaria/sangre , Ejercicio Físico/fisiología , Consumo de Oxígeno/fisiología , Anciano , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/rehabilitación , Prueba de Esfuerzo , Tolerancia al Ejercicio , Hemodinámica , Humanos , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Pruebas de Función Respiratoria
10.
Ocul Immunol Inflamm ; 5(3): 149-55, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9326759

RESUMEN

Corneal allograft rejection culminates in a series of interactions between different classes of antigen presenting cells, cytokines and leukocytes. Tumor necrosis factor-alpha (TNF-alpha) was recently reported to be elevated in acute rejection of solid organ transplants. This cytokine is released early in immune activation and may be detected in the peripheral circulation. Serial determinations of TNF-alpha serum levels were performed following experimental corneal allografts. Lewis rats received 3.5 mm orthotopic corneal grafts of MHC-incompatible Wistar-Furth donors. TNF-alpha concentrations were measured in serum samples collected pre- and postoperatively and measured by micro ELISA. Clinical observations revealed graft rejection in 65.5% of corneal transplants 14 +/- 4 days following grafting. The mean serum level of TNF-alpha in control animals without corneal graft (group I) was 41 +/- 12 pg/ml. Animals following keratoplasty without allograft rejection (group II) showed a mean TNF-alpha level of 54 +/- 16 pg/ml that did not differ from group I. The rejection group III displayed significantly higher TNF-alpha levels (98 +/- 16 pg/ml, p < 0.05). These significantly elevated levels were found even before the diagnosis of rejection was established by clinical criteria. These data suggest systemic immunoreactivity to corneal allografts. Elevated levels of cytokines may provide valuable information in recipients undergoing rejection and may also provide a rationale for systemic immunotherapy in some instances.


Asunto(s)
Córnea/química , Trasplante de Córnea , Factor de Necrosis Tumoral alfa/análisis , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Rechazo de Injerto/sangre , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas WF
11.
Arterioscler Thromb Vasc Biol ; 17(6): 1106-13, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9194761

RESUMEN

The purpose of this study was to evaluate fibrinolytic potential at rest and after a fibrinolytic stressor in men with a history of myocardial infarction (MI) compared with an age- and activity-matched group of men without coronary artery disease (CAD). All men were currently enrolled in exercise programs. Tissue-type plasminogen activator (TPA) and plasminogen activator inhibitor 1 (PAI-1) activity and antigen levels were measured at rest and after a maximal exercise test. A 2 x 2 (group x time) ANOVA with repeated measures was used to evaluate fibrinolytic potential. Bivariate regressions were conducted to evaluate relations between fibrinolytic potential and maximal oxygen uptake (VO2max). Age was similar between groups (CAD, 57.5 +/- 6.6; non-CAD, 58.1 +/- 7.3 years); however, VO2max was higher in non-CAD subjects (36.2 +/- 6.2 vs 27.5 +/- 5.9 mL.kg-1.min-1). Mean +/- SEM resting TPA and PAI-1 activities were similar between CAD and non-CAD subjects (TPA, 2.8 +/- 0.2 vs 2.8 +/- 0.2 IU/mL; PAI-1, 15.9 +/- 3.1 vs 13.1 +/- 4.1 AU/mL). Both groups showed similar significant increases in TPA activity with exercise (P < .05), and postexercise TPA activity was also similar (CAD, 9.1 +/- 2.0 IU/mL; non-CAD, 11.7 +/- 2.6 IU/mL). Both groups also showed similar significant decreases in PAI-1 activity with exercise (P < .05) and no differences in postexercise PAI-1 activity (CAD, 13.2 +/- 2.5 AU/mL; non-CAD, 10.4 +/- 3.6 AU/mL). Significantly higher resting TPA antigen levels were seen in CAD (14.8 ng/mL) than non-CAD (10.2 ng/mL) subjects (P < .05), but neither group showed significant changes with exercise (CAD, 12.9 ng/mL; non-CAD, 11.8 ng/mL). Resting PAI-1 antigen was similar in the two groups (CAD, 71.4 ng/mL; non-CAD, 74.2 ng/mL) and did not significantly change with exercise (CAD, 77.9 ng/mL; non-CAD, 72.3 ng/mL). VO2max was positively correlated with postexercise TPA activity (r = .52, P < .05) and negatively correlated with resting TPA antigen (r = -.43, P < .05). Resting TPA antigen was also directly correlated with body mass index (r = .63, P < .05). The finding that functional fibrinolytic activity was not different in physically active men with and without CAD contrasts with previous reports. This suggests that matching subjects on the bases of age and habitual physical activity status and controlling exercise intensity are important factors to consider when evaluating fibrinolytic potential.


Asunto(s)
Fibrinólisis , Infarto del Miocardio/enzimología , Inhibidor 1 de Activador Plasminogénico/metabolismo , Activador de Tejido Plasminógeno/metabolismo , Anciano , Humanos , Masculino , Persona de Mediana Edad , Esfuerzo Físico , Aptitud Física
12.
J Cardiopulm Rehabil ; 16(6): 394-401, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8985798

RESUMEN

PURPOSE: This study compared the accuracy of common clinical treadmill and arm ergometry equations in estimating the rate of oxygen consumption for males with coronary artery disease. METHODS: Measured and estimated submaximal and maximal oxygen consumption (VO2sub and VO2max) were compared during clinical treadmill (TM) and arm ergometry (AE) graded exercise tests in 15 males with established coronary artery disease (CAD). Estimated VO2sub and VO2max were derived from popular modality specific estimation equations, including those of the American College of Sports Medicine, Bruce and colleagues, Balady and colleagues, and Manfre and colleagues. RESULTS: The American College of Sports Medicine (ACSM) 1991 TM equation overestimated VO2sub from 0.3 +/- 0.6 to 1 +/- 0.7 metabolic equivalents (METS) and VO2max by 3 +/- 3 METS, whereas the Bruce Normal Submax and Bruce Cardiac Submax equations inaccurately estimated VO2sub from -1 +/- 0.6 to 0.9 +/- 0.7 METS. The Bruce Active Max and Bruce Sedentary Max equations overestimated VO2max from 1 +/- 2 to 2 +/- 2 METS, whereas the Bruce Cardiac Max equation accurately estimated oxygen consumption at maximal exercise. The ACSM and Manfre Healthy AE equations underestimated VO2sub at low and intermediate workloads from 0.4 +/- 0.4 to 0.8 +/- 0.4 METS. However, the Balady Male and Manfre Cardiac AE equations underestimated VO2 at each submaximal work load from 0.6 +/- 0.3 to 1 +/- 0.6 METS and at maximal work loads from 0.8 +/- 0.9 to 2 +/- 0.8 METS. The ACSM and Manfre Healthy AE equations accurately estimated VO2 at greater submaximal work loads and at maximal exercise. CONCLUSIONS: These data suggest that the ability to estimate VO2 in males with CAD is more accurately performed during nonweight-bearing arm activity, although the reason is not entirely understood, and significant inconsistencies exist in the ability to accurately estimate VO2 during treadmill exercise. These data further suggest concern regarding exercise prescription from estimated values derived from both treadmill and arm ergometry tests, because submaximal, and in some instances maximal, estimations were inaccurate. Future research should focus on the development of accurate estimations for those with CAD, primarily during submaximal work.


Asunto(s)
Enfermedad Coronaria/metabolismo , Prueba de Esfuerzo , Consumo de Oxígeno , Anciano , Brazo/fisiopatología , Enfermedad Coronaria/fisiopatología , Ergometría , Humanos , Masculino , Persona de Mediana Edad , Carga de Trabajo
13.
Exp Eye Res ; 60(6): 603-5, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7641843

RESUMEN

In order to determine the dose responsiveness to radiation of ocular melanoma, we conducted an in vitro dose-response study on a monolayer cell culture using a clonogenic assay. The effects on cell survival were determined relative to unirradiated controls. A human epithelioid ocular melanoma cell line, OM431, was maintained in tissue culture and serial dilutions of viable cells were plated in flasks, allowed to settle and attach for 48 h, and subsequently irradiated with 1-10 Gy in single fractions. After 2 weeks, the number of reproducing clones (forming colonies with greater than 32 cells or five generations) were counted. The surviving fractions of cells were plotted on a cell survival curve using the linear quadratic model. The survival curve showed a large initial shoulder followed by an exponential decline in growth. Our data suggest that the OM431 ocular melanoma cell line responds to irradiation in a manner similar to other melanoma cell lines and is relatively radioresistant especially at lower doses.


Asunto(s)
Neoplasias del Ojo/radioterapia , Rayos gamma , Melanoma/radioterapia , Supervivencia Celular/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Humanos , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
14.
Invest Ophthalmol Vis Sci ; 36(1): 52-61, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7822159

RESUMEN

PURPOSE: Monoclonal antibodies (mAb) have generated interest as therapeutic agents. Limited data are available on the treatment of corneal graft rejection. The purpose of this study was to assess the use of topically applied mAb on experimental corneal grafts. METHODS: W 3/25, an IgG 1 mouse antirat mAb that recognizes a CD4+ cell subset, was used to treat Lewis recipient rats that received orthotopic corneal grafts of Wistar-Furth donors. Recipients were randomly assigned to receive topically applied drops of liposome-incorporated anti-CD4 mAb (LIP-anti-CD4 mAb), an equivalent amount of free anti-CD4 mAb, an isotype-matched control mAb encapsulated in liposomes (LIP-control mAb), or empty liposomes (emp-LIP) 5 times daily for 10 days. To investigate the immunologic effect of mAb treatment, flow cytometry of the targeted cells and cytotoxic activity of lymphocytes were analyzed. RESULTS: Application of LIP-anti-CD4 mAb was effective in reducing the rejection rate (P < .05) and in prolonging the mean survival time of corneal grafts that underwent rejection (P < .05). In contrast, no significant effect on graft outcome was observed after the application of control agents. Flow cytometry analysis did not reveal systemic depletion of the targeted lymphocyte subset in any anti-CD4 mAb treated animals. Rejected grafts elicited a cellular cytotoxic immune response in a cell-mediated lymphocytotoxic assay independent of the treatment given. CONCLUSION: The results suggest that treatment with topically applied LIP-anti-CD4 mAb prolongs graft survival in orthotopic corneal grafts in a rat model. The beneficial effect of LIP-anti-CD4 mAb, probably due to enhanced intraocular delivery, was achieved by using relatively low doses of mAb.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Linfocitos T CD4-Positivos/inmunología , Queratoplastia Penetrante/inmunología , Administración Tópica , Animales , Anticuerpos Monoclonales/uso terapéutico , Córnea/efectos de los fármacos , Córnea/patología , Modelos Animales de Enfermedad , Portadores de Fármacos , Femenino , Supervivencia de Injerto/inmunología , Liposomas , Soluciones Oftálmicas , Distribución Aleatoria , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas WF , Trasplante Homólogo
15.
J Clin Neuroophthalmol ; 13(4): 254-7, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8113437

RESUMEN

Two patients presented with unilateral dilated and poorly reactive pupils and were found to have a previously unsuspected intraocular iron foreign body. Both of them had normal vision and one had normal color of the iris so that the condition was missed by several physicians. The pupils reacted normally to pilocarpine 1% and also showed response to dilute (0.1%) pilocarpine. There was no response to phospholine iodide. These findings indicate that the mydriasis was due to a local siderotic parasympathetic neuropathy of the pupil.


Asunto(s)
Cuerpos Extraños en el Ojo/complicaciones , Hierro , Midriasis/etiología , Trastornos de la Pupila/etiología , Adulto , Cuerpos Extraños en el Ojo/cirugía , Lesiones Oculares Penetrantes/complicaciones , Lesiones Oculares Penetrantes/cirugía , Humanos , Masculino
16.
Am J Ophthalmol ; 116(5): 622-7, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8238224

RESUMEN

We investigated the ability of collagen shields impregnated with gentamicin sulfate and dexamethasone to deliver medication into rabbit eyes. We compared the aqueous humor gentamicin and dexamethasone levels delivered by collagen shield and subconjunctival injection therapy at five time points over a ten-hour period, by using a fluorescence polarization immunoassay and high-pressure liquid chromatography. Our in vitro studies showed that impregnated collagen shields released most of the gentamicin within the first 30 minutes of elution, whereas dexamethasone was released gradually over a ten-hour period. The collagen shields impregnated with gentamicin and dexamethasone produced aqueous gentamicin levels that were significantly lower (P = .014) than those produced by subconjunctival injection therapy at 30 minutes and that were comparable to subconjunctival injection therapy at the other time points. Minimum inhibitory concentrations of gentamicin (approximately 4 micrograms) were observed in aqueous humor within 30 minutes in rabbits that received subconjunctival injections and at one hour in rabbits treated with impregnated collagen shields. The impregnated collagen shields produced aqueous dexamethasone levels that were significantly lower (P = .004) than those produced by subconjunctival injection therapy at one hour, significantly higher (P = .028) than subconjunctival injection therapy at six hours, and comparable to subconjunctival injection therapy at the other time points. Collagen shield delivery of gentamicin-dexamethasone may be comparable to subconjunctival injections and provide an alternative therapy after intraocular surgery.


Asunto(s)
Colágeno , Dexametasona/administración & dosificación , Sistemas de Liberación de Medicamentos , Gentamicinas/administración & dosificación , Animales , Humor Acuoso/efectos de los fármacos , Humor Acuoso/metabolismo , Cromatografía Líquida de Alta Presión , Conjuntiva , Córnea/efectos de los fármacos , Córnea/metabolismo , Dexametasona/farmacocinética , Portadores de Fármacos , Combinación de Medicamentos , Femenino , Inmunoensayo de Polarización Fluorescente , Gentamicinas/farmacocinética , Inyecciones , Conejos
17.
Ophthalmology ; 100(6): 890-6, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8510902

RESUMEN

PURPOSE: To study the effects of different formulations of topical cyclosporine (Cyclosporin A [CsA]) on corneal allograft rejection in a rat model. METHODS: Female Lewis rats received penetrating keratoplasties from female Wistar-Furth donors. A total of 78 allogeneic grafts were performed. An additional 15 syngeneic grafts (Lewis) were used as technical controls. Two CsA preparations with equivalent drug concentrations (2.1 mg/ml) were applied as drops: CsA encapsulated in large unilamellar liposomes (CsA-LIP) and CsA dissolved in olive oil (CsA-DR). Allogeneic grafts were randomly assigned to receive CsA-LIP or CsA-DR beginning on the day of surgery five times daily for 10 days. Animals without any treatment or receiving empty liposomes (EM-LIP) were used as treatment controls. Grafts were graded three times weekly and a rejection index was generated based on graft clarity, neovascularization, and vessel size. RESULTS: All syngeneic grafts remained clear over the observation period of 60 days. Rejected allogeneic grafts without any treatment and those receiving EM-LIP or CsA-DR showed a mean survival time (+/- standard deviation) of 14 +/- 4, 14 +/- 5, and 14 +/- 4 days, respectively. There was no significant difference in mean survival time between the grafts without any treatment and those in CsA-DR or EM-LIP treatment groups. The mean survival time of rejected grafts in animals receiving CsA-LIP was prolonged to 20 +/- 4 days. There was a significant difference in the mean survival time between the CsA-LIP treatment group and groups receiving CsA-DR, EM-LIP, or no treatment (P < or = 0.05). The Kaplan-Meier survival curve of the CsA-LIP treatment group was significantly different from the other experimental groups. The graft survival rate in the CsA-LIP group was 77%, whereas the rate was 37% in the non-treated group, 45% in the CsA-DR group, and 36% in the EM-LIP group. CONCLUSION: Encapsulation of CsA in liposomes might be a promising formulation for use in the prevention of corneal graft rejection.


Asunto(s)
Córnea/efectos de los fármacos , Ciclosporina/uso terapéutico , Supervivencia de Injerto/efectos de los fármacos , Queratoplastia Penetrante , Animales , Córnea/patología , Córnea/cirugía , Ciclosporina/administración & dosificación , Ciclosporina/sangre , Portadores de Fármacos , Femenino , Liposomas , Soluciones Oftálmicas , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas WF , Trasplante Homólogo
18.
Arch Ophthalmol ; 103(4): 553-4, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3985839

RESUMEN

A 51-year-old man presented with a three-month history of a red and painful right eye. A corneal ulcer was diagnosed, and laboratory workup failed to disclose an etiologic factor. A white tumor, with an irregular and calcified surface, found in the superior tarsal conjunctiva, was considered to be the cause of the corneal ulcer. The tumor proved to be a pilomatrixoma that presumably developed from a congenitally ectopic hair follicle.


Asunto(s)
Neoplasias de los Párpados/patología , Neoplasias Cutáneas/patología , Neoplasias de la Conjuntiva/complicaciones , Neoplasias de la Conjuntiva/patología , Úlcera de la Córnea/complicaciones , Úlcera de la Córnea/patología , Neoplasias de los Párpados/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/complicaciones
19.
Arq. bras. oftalmol ; 47(3): 115-7, 1984.
Artículo en Portugués | LILACS | ID: lil-25357

RESUMEN

Um caso de sindrome de Moebius associado a anomalia de Poland e laringomalacia e relatado. O paciente apresenta paralisia do sexto e setimo pares craniano em adicao a ausencia do musculo peitoral maior direito afundamento do hemitorax direito com hipoplasia da segunda, terceira e quarta costelas; a mao direita apresenta hipoplasia do primeiro, segundo e terceiro dedos e sindactilia do quarto e quinto dedos. Pe torto congenito bilateral, em equinovaro, foi observado


Asunto(s)
Lactante , Humanos , Masculino , Anomalías Múltiples , Parálisis Facial , Sindactilia
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