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1.
Arch Intern Med ; 150(7): 1511-3, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2369249

RESUMEN

The opportunity for residents to moonlight is threatened by legal liability concerns and legislation designed to limit the duration of workdays and workweeks. We sought the opinion of all 40 second- or third-year residents and fellows in a hybrid university/community hospital internal medicine residency program regarding their motivation to moonlight and the value of their experiences. Sixty-five percent were moonlighters; moonlighters had a higher average debt ($41 644) than nonmoonlighters ($32 917). Residents viewed moonlighting as a positive educational experience that helped them with career decisions. They believed they acquired important skills and knowledge not learned elsewhere, and that moonlighting did not interfere with their job and educational responsibilities. A program in operation for 10 years that was designed to control, monitor, and facilitate moonlighting experiences is described. We believe our residents' positive views may be in part a result of the supervision and integration of moonlighting in a residency training program with a controlled workload.


Asunto(s)
Actitud del Personal de Salud , Internado y Residencia , Tolerancia al Trabajo Programado , Trabajo , Educación Médica/economía , Factores Socioeconómicos
2.
Cardiovasc Res ; 39(2): 327-38, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9798518

RESUMEN

OBJECTIVE: Our aim was to assess whether exposure to oxidized thiols--a known usual consequence of oxidant stress--has the potential to affect the vascular repair response to angioplasty-induced injury. In addition, we also assessed the role of redox active metals in disulfide effects. METHODS: In 82 rabbits submitted to overdistention of iliac arteries, the following variables were analyzed: neointimal thickening, immunoreactivity to Proliferating Cell Nuclear Antigen, and cellular and collagen densities. RESULTS: A single intraarterial challenge of oxidized glutathione (GSSG, 6.5 mumol/kg) during and immediately after injury triggered a marked increase of the vascular repair reaction, as follows: (A) at day 7 after injury, there was a 2.7-fold increase in proliferation (p < 0.001 vs. control); (B) at day 14, there was increase of intimal/medial area ratio to 1.35 +/- 0.14, vs. 0.56 +/- 0.08 in controls. Proliferating cells increased to 5.5 +/- 0.8 cells/mm2, vs. 2.2 +/- 0.5 in controls (p < 0.002 for both variables). Overall cellularity was enhanced 2.2-fold; (C) at day 28, there was ongoing vessel wall proliferation, contrarily to controls. All GSSG effects were completely prevented by co-infusion of reduced glutathione (GSH) and were mimicked by cystine (6.5 mumol/kg). The uninjured artery showed no response to disulfides. To assess the role of redox active metals in GSSG action, the effects of 1,10-phenanthroline or N-CBZ-Pro-Leu-Gly hydroxamic acid (HXA), metal chelators with metalloproteinase inhibitor properties, were evaluated. Both compounds totally blocked the GSSG-induced amplification of vascular responses. In rabbits not exposed to GSSG, HXA decreased neointimal thickening by 50% (p < 0.05). CONCLUSIONS: Exposure to excess disulfide levels early after vascular balloon injury markedly amplified the late cellular response through interaction with redox active metals. These pathways can potentially mediate noxious effects of oxidative stress in vessels.


Asunto(s)
Disulfuro de Glutatión/farmacología , Glutatión/farmacología , Arteria Ilíaca/lesiones , Compuestos de Sulfhidrilo/farmacología , Animales , Cateterismo , División Celular/efectos de los fármacos , Quelantes/farmacología , Colágeno/metabolismo , Inhibidores Enzimáticos/farmacología , Glutatión/sangre , Ácidos Hidroxámicos/farmacología , Arteria Ilíaca/efectos de los fármacos , Arteria Ilíaca/metabolismo , Arteria Ilíaca/patología , Inmunohistoquímica , Masculino , Metaloendopeptidasas/antagonistas & inhibidores , Oxidación-Reducción , Fenantrolinas/farmacología , Antígeno Nuclear de Célula en Proliferación/análisis , Conejos , Factores de Tiempo , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología
3.
Cardiovasc Res ; 47(3): 436-45, 2000 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-10963717

RESUMEN

The prominent role of redox processes in tissue injury and in vascular cell signaling suggest their involvement in the repair reaction to vessel injury, which is a key determinant of restenosis post-angioplasty. Experimental studies showed a protective effect of superoxide dismutase or antioxidants on vasospasm, neointimal thickening or remodeling after balloon injury. It was also shown that oxidized thiols induce chelatable metal-dependent amplification of the vascular repair reaction. Ongoing or completed clinical trials show a promising effect of the antioxidant probucol against restenosis. However, few studies addressed the molecular physiological mechanisms underlying the redox hypothesis of restenosis. We recently showed evidence for marked oxidative stress early after balloon injury, with superoxide production mediated primarily by non-endothelial NAD(P)H oxidase-type flavoenzyme(s). This effect was closely related to the degree of injury. There is evidence supporting a role for such early redox processes in apoptotic cell loss and NF-kappa B activation. We present new data on the time course of oxidative stress after balloon injury of intact rabbit iliac arteries. Our data show that despite substantial neointimal growth and lumen narrowing, superoxide production and glutathione levels are unaltered at day 14 and 28 after balloon injury. At day 7 after injury, the peak neointimal proliferation in this model, there was significant decrease of vascular superoxide dismutase activity, without clear evidence of spontaneous superoxide production. Thus, oxidative stress after injury is likely to be an early transient event, which parallels the inflammatory and proliferative phases of the vascular response. We propose that such early redox processes act as dose-dependent signal transducers of gene programs that affect the final repair.


Asunto(s)
Enfermedad Coronaria/metabolismo , Endotelio Vascular/metabolismo , Estrés Oxidativo , Transducción de Señal , Angioplastia Coronaria con Balón/efectos adversos , Animales , Antioxidantes/uso terapéutico , División Celular , Enfermedad Coronaria/patología , Enfermedad Coronaria/terapia , Endotelio Vascular/lesiones , Endotelio Vascular/patología , Humanos , Masculino , Oxidación-Reducción , Conejos , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Túnica Íntima/lesiones , Túnica Íntima/metabolismo , Túnica Íntima/patología
4.
Free Radic Biol Med ; 29(9): 889-99, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11063914

RESUMEN

Vascular NAD(P)H oxidase activity contributes to oxidative stress. Thiol oxidants inhibit leukocyte NADPH oxidase. To assess the role of reactive thiols on vascular oxidase, rabbit iliac/carotid artery homogenates were incubated with distinct thiol reagents. NAD(P)H-driven enzyme activity, assessed by lucigenin (5 or 250 microM) luminescence, was nearly completely (> 97%) inhibited by the oxidant diamide (1mM) or the alkylator p-chloromercuryphenylsulfonate (pCMPS, 0.5mM). Analogous inhibition was also shown with EPR spectroscopy using DMPO as a spin trap. The oxidant dithionitrobenzoic acid (0.5mM) inhibited NADPH-driven signals by 92% but had no effect on NADH-driven signals. In contrast, the vicinal dithiol ligand phenylarsine oxide (PAO, 1 microM) induced minor nonsignificant inhibition of NADPH-driven activity, but significant stimulation of NADH-triggered signals. The alkylator N-ethyl maleimide (NEM, 0.5mM) or glutathione disulfide (GSSG, 3mM) had no effect with each substrate. Coincubation of N-acetylcysteine (NAC, 3mM) with diamide or pCMPS reversed their inhibitory effects by 30-60%, whereas NAC alone inhibited the oxidase by 52%. Incubation of intact arterial rings with the above reagents disclosed similar results, except that PAO became inhibitor and NAC stimulator of NADH-driven signals. Notably, the cell-impermeant reagent pCMPS was also inhibitory in whole rings, suggesting that reactive thiol(s) affecting oxidase activity are highly accessible. Since lack of oxidase inhibition by NEM or GSSG occurred despite significant cellular glutathione depletion, change in intracellular redox status is not sufficient to account for oxidase inhibition. Moreover, the observed differences between NADPH and NADH-driven oxidase activity point to complex or multiple enzyme forms.


Asunto(s)
Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/metabolismo , Glutatión/metabolismo , NADH NADPH Oxidorreductasas/antagonistas & inhibidores , Reactivos de Sulfhidrilo/farmacología , Acridinas , Animales , Vasos Sanguíneos/enzimología , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Arteria Ilíaca/efectos de los fármacos , Arteria Ilíaca/metabolismo , Técnicas In Vitro , Oxidación-Reducción , Estrés Oxidativo , Conejos
5.
Nutrition ; 17(2): 100-4, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11240336

RESUMEN

Refeeding syndrome encompasses fluid and electrolyte imbalances and metabolic, intestinal, and cardiorespiratory derangements associated with appreciable morbidity and mortality. Although refeeding syndrome has been well documented in concentration-camp subjects, and more recently during parenteral therapy of critically ill patients, little is known about the importance of refeeding syndrome during recovery from a hunger strike. Thus, we studied the response to a four-step dietary replenishment routine in eight hunger strikers who refused food for 43 d. In this retrospective, observational study, we assessed the safety and efficacy of the refeeding procedure and analyzed the clinical and nutritional course of the cohort during both starvation and refeeding, mainly on the basis of clinical as well as a few biochemical determinations. During starvation, average weight loss was about 18% and, with the exception of occasional oral vitamins and electrolytes, the subjects consumed only water. Available body-composition and biochemical profiles showed no clinically significant changes during starvation, but one-half of the group displayed spontaneous diarrhea at some time before refeeding. Stepwise nutritional replenishment lasted for 9 d, after which all patients tolerated a full, unrestricted diet. Only one episode of diarrhea occurred during this phase, and both clinical and biochemical indexes confirmed a favorable clinical course, without any manifestation of refeeding syndrome. In conclusion, we observed the following: 1) Hypophosphatemia and other micronutrient imbalances did not occur, nor was macronutrient intolerance detected. 2) Despite some episodes of diarrhea, nutritional replenishment was not associated with significant enteral dysfunction. 3) There was some fluid retention, but this was mild. 4) Acute-phase markers were abnormally elevated during the refeeding phase, without associated sepsis or inflammation.


Asunto(s)
Composición Corporal , Peso Corporal/fisiología , Ingestión de Alimentos , Prisioneros , Inanición/terapia , Proteínas de Fase Aguda/análisis , Adulto , Análisis Químico de la Sangre , Líquidos Corporales , Estudios de Cohortes , Diarrea/etiología , Electrólitos/administración & dosificación , Electrólitos/sangre , Ayuno , Femenino , Fluidoterapia , Humanos , Masculino , Persona de Mediana Edad , Nutrición Parenteral , Estudios Retrospectivos , Seguridad , Inanición/etiología , Inanición/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Vitaminas/administración & dosificación
6.
Angiology ; 47(6): 549-56, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8678329

RESUMEN

Heparinization is a routine procedure during angioplasty; however, its consequences on the late vascular response to a severe injury are unclear. The authors' objective was to explore the effect of a single heparin bolus at the time of a severe vascular injury on late intimal proliferation and neointimal thickening. The iliac artery of 57 normolipemic rabbits was overdistended with a balloon catheter. Heparin (250 IU/kg i.v.) was given to 29 rabbits ten minutes before angioplasty, whereas 28 rabbits served as untreated controls. Neointimal thickening was prominent at fourteen days after injury and reached near-maximal values at day 28. The intimal/medial area ratio was reduced by an average 28.3% with heparin (at day 28: 2.19 +/- 0.51 vs 1.57 +/- 0.59, control vs heparin, P = 0.02). Neointimal cells stained positively for HHF-35 antibody, directed against smooth muscle cell antigens. Neointimal proliferation, quantified through the number of cell nuclei peroxidase-stained for PCNA/cyclin antigen, was significantly decreased by 43% and 49% with heparin, respectively, at days 7 and 14 after injury. These data suggest that early exposure even to low doses of heparin accounts for much of its inhibitory effect in vascular response to injury; such an effect might prove important in interpreting results of human trials of interventions against restenosis.


Asunto(s)
Anticoagulantes/farmacología , Cateterismo , Heparina/farmacología , Arteria Ilíaca/lesiones , Túnica Íntima/efectos de los fármacos , Animales , División Celular/efectos de los fármacos , Constricción Patológica/prevención & control , Depresión Química , Técnicas para Inmunoenzimas , Masculino , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Conejos , Recurrencia , Factores de Tiempo , Túnica Íntima/citología
7.
Pol Merkur Lekarski ; 1(1): 32-3, 1996 Jul.
Artículo en Polaco | MEDLINE | ID: mdl-9156888

RESUMEN

96 patients suffering was examined. 46 patients over one year was offending kinesytherapy during a special active music therapy techniques was used. It was the form of breathing exercises. 50 patients during the period of one year was under program of traditional breathing kinesytherapy. The authors observed a greater effectiveness of music therapy which decrease bronchial resistances, increases physical self-feeling and reduces anxiety level.


Asunto(s)
Asma/rehabilitación , Ejercicios Respiratorios , Voz/fisiología , Adulto , Humanos , Musicoterapia
8.
Wiad Lek ; 47(17-18): 654-8, 1994 Sep.
Artículo en Polaco | MEDLINE | ID: mdl-7571613

RESUMEN

In 67 patients with classical or certain (according to the ARA criteria) rheumatoid arthritis, the concentration of serum sulphydryl groups (SH) was studied. A statistically significantly decreased concentration of these groups was found in the patients with rheumatoid arthritis (397.1 +/- 31.7 mumol/l). Besides that the studies demonstrated that the concentration of serum SH groups depended on the age of the patients and duration of the disease. For example, in time range of disease duration from one to 15 years, the concentration of SH groups was 395.9 +/- 28.5 mumol/l, from 16 to 20 years: 337.0 +/- 32.0 mumol/l, and from 26 to 30 years: 290.0 +/- 17.2 mumol/l. The changes of the concentration of serum SH groups in patients with rheumatoid arthritis may become, according to many researchers, a very sensitive biochemical index in the assessment of the course of the inflammatory process.


Asunto(s)
Envejecimiento/fisiología , Artritis Reumatoide/sangre , Compuestos de Sulfhidrilo/sangre , Adulto , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
9.
Ortop Traumatol Rehabil ; 2(2): 69-71, 2000 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-18034124

RESUMEN

Spinal pain can afflict both the sick and the healthy, even those with an anatomically correct spine. Such complaints force many people to change profession or even go on disability pension. Both the social and professional aspects are very important, then, in the rehabilitation of these people, since spinal pain syndromes impair the patient's locomotor capacity and his/her ability to work for a living. In view of this, medical rehabilitation takes on particular important, and especially the laser photobiostimulation technique in use for several years now.
Biostimulating lasers have analgesis, anti-inflammatory, and antiallergenic effects, and relieve muscle cramps; they also improve metabolism and regenerate cells and tissue. Laser photobiostimulation is an effective, quick, aseptic therapy, with no age limitations or side effects.

20.
Artículo en Inglés | MEDLINE | ID: mdl-16787290

RESUMEN

Sepsis remains one of the leading causes of death in intensive care units, despite recent acquired knowledge on pathophysiology and treatment. Several mediators of inflammation and cellular damage have been implicated in the complex host-pathogen interaction underlying organ damage and multisystem organ failure , which are hallmarks of sepsis and common causes of death. Among such mediators, reactive oxygen/nitrogen species have been increasingly studied in the context of direct cytotoxicity as well as altered cell signaling. While the generation of reactive oxygen species by inflammatory cells in sepsis is well known, recent studies have shown that vascular cells are able to release reactive oxygen intermediates that may be associated with endothelial dysfunction of sepsis. These compounds can activate transcription factors such as NF-kappaB that sustain inflammatory process or enzymatic systems like poly(ADP-ribose) polymerase-1, which are involved in apoptosis and cytotoxicity of sepsis. Our laboratory recently showed that platelet-derived exosomes from septic patients carry components of a superoxide-producing NADPH oxidase and can, at least in vitro, induce apoptosis of endothelial and vascular smooth muscle cells by a ROS-dependent pathway. Taken together, these data show that reactive oxygen species are involved in cell signaling and organ injury in sepsis. Efforts must be made to identify the precise contribution of these factors in septic process, in order to clarify the mechanisms associated with the disease. This will certainly lead to discovery of therapeutic strategies that can help us to mitigate vascular dysfunction of sepsis.


Asunto(s)
Células Endoteliales/metabolismo , Sepsis/metabolismo , Animales , Células Endoteliales/microbiología , Células Endoteliales/fisiología , Radicales Libres/metabolismo , Humanos , Oxidación-Reducción , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Sepsis/microbiología
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