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1.
APMIS ; 105(6): 449-56, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9236862

RESUMEN

The GroEL protein of Pseudomonas aeruginosa belongs to the bacterial 60-65 kDa heat shock protein family. A strong antibody response to GroEL has been found in cystic fibrosis (CF) patients with chronic pulmonary infection caused by P. aeruginosa. Clonotypes of IgG1 and IgG2 antibodies against GroEL were studied in 60 consecutive sera from 18 CF patients with chronic P. aeruginosa infection using isoelectric focusing in combination with affinity immunoblotting. The persistent antigenic stimulation in CF patients with chronic P. aeruginosa infection induced numerous IgG1 and particularly IgG2 antibody clones against GroEL. The appearance of new clones with time reflected the long duration of the chronic infection. A striking addition of new clonotypes during the observation period occurred when a new unrelated bacterium (Burkholderia cepacia) had become established as a cause of the pulmonary infection, or when the P. aeruginosa infection became chronic.


Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Diversidad de Anticuerpos , Chaperonina 60/inmunología , Fibrosis Quística/inmunología , Infecciones por Pseudomonas/inmunología , Adolescente , Adulto , Anticuerpos Antibacterianos/clasificación , Enfermedad Crónica , Fibrosis Quística/microbiología , Femenino , Humanos , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/química , Masculino , Infecciones por Pseudomonas/microbiología
2.
Pancreas ; 5(6): 652-7, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1980734

RESUMEN

The purpose of the study was to examine the transhepatic and peripheral effects of somatostatin (SN) infusion on plasma glucose and insulin during insulin (IN) infusion. Hepatic blood flow was measured electromagnetically during intermittent sampling from the portal and hepatic veins, femoral artery, and right external jugular vein. Hepatic blood flow [sum of portal vein (PV) and hepatic artery] was similar during IN or IN + SN infusions. IN concentrations decreased in the portal vein from 374.8 +/- 50.3 to 295.8 +/- 25.9 pM (p less than 0.01) when SN was infused with IN. Hepatic venous plasma IN concentration also decreased from 143.6 +/- 26.6 to 88.3 +/- 10.1 pM (p less than 0.01). Plasma IN concentrations in the femoral artery and jugular vein remained unchanged. Hepatic insulin extraction changed from 64 +/- 4% during IN to 72 +/- 3% during IN + SN (p less than 0.01). Hepatic clearance and total body clearance were unchanged. Peripheral venous glucose with a nadir of 3.82 +/- 0.2 mM during IN alone decreased to a nadir of 3.16 +/- 0.27 mM (p less than 0.01) during IN + SN infusion. Mean portal venous glucose concentrations were 5.0 +/- 0.27 and 3.4 +/- 0.19 mM, respectively (p less than 0.01). In two additional experiments in which endogenous C-peptide concentrations were examined in the portal vein and femoral artery, C-peptide levels were lower during IN + SN compared to IN alone. We conclude that SN used to suppress endogenous insulin secretion increases hepatic insulin extraction, lowers glucose concentrations, and suppresses endogenous C-peptide levels to a greater extent than insulin infusion alone.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Glucemia/análisis , Insulina/sangre , Somatostatina/farmacología , Animales , Péptido C/sangre , Perros , Glucosa/metabolismo , Infusiones Intravenosas , Insulina/administración & dosificación , Insulina/análisis , Hígado/irrigación sanguínea , Hígado/química , Hígado/metabolismo , Flujo Sanguíneo Regional
3.
Alcohol Clin Exp Res ; 15(4): 711-6, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1928648

RESUMEN

Animals exposed to ethanol in utero are typically hyperresponsive to stressors in adulthood as indicated by increased adrenocortical activation and/or deficits in response inhibition or recovery following stress. In the present study we reasoned that a deficit in feedback control of pituitary-adrenal activity might underlie this hyperresponsiveness in fetal ethanol-exposed (FEE) animals. Further, we hypothesized that a long-term decrease in hippocampal glucocorticoid receptor concentration, induced by prenatal ethanol exposure, might mediate such a deficit in pituitary-adrenal feedback regulation. Male and female Sprague-Dawley rats from prenatal ethanol (E), pair-fed (PF), and control (C) treatment groups were tested in adulthood for determination of cytosolic hippocampal glucocorticoid receptor binding. No significant differences in specific binding (Bmax) or binding affinity (Kd) of either type I or type II glucocorticoid receptors were found among animals from E, PF, and C conditions. There were, however, significant sex differences in receptor concentration and binding affinity; females showed significantly greater maximal binding and significantly lower binding affinity than males. These data do not support the hypothesis that prenatal ethanol exposure induces a long-term decrease in hippocampal glucocorticoid receptors in animals tested under basal nonstressed conditions. However, these data do not preclude the possibility that receptor binding capacity may be differentially affected in E, PF, and C animals during stress.


Asunto(s)
Etanol/toxicidad , Hipocampo/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal , Receptores de Glucocorticoides/efectos de los fármacos , Análisis de Varianza , Animales , Femenino , Hipocampo/metabolismo , Masculino , Embarazo , Ratas , Ratas Endogámicas , Factores Sexuales
4.
Clin Orthop Relat Res ; (219): 112-9, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3581559

RESUMEN

Accurate assessment of total hip and knee alignment requires a single-exposure weight-bearing roentgenogram of the involved limb. The problem with single-exposure technique is that a good exposure of the hip overexposes the lower leg. This problem is solved by using leaded acrylic wedges, which, when placed in front of the X-ray tube (collimator), block excessive radiation to the lower limb and create an evenly exposed film of the entire lower extremity. The development of these collimator wedge filters and the advent of newer fast-speed film and screens have reduced the amount of radiation absorbed by the patient by eight times or more. Guided by a chart to interchange and choose between film/screen combinations, the method and technique provides the surgeon with an exact alignment of the limb and joints for all kinds of operations.


Asunto(s)
Articulación de la Cadera/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Tecnología Radiológica/métodos , Humanos , Articulación de la Rodilla/cirugía , Prótesis de la Rodilla , Osteotomía , Dosis de Radiación , Radiografía
5.
J Arthroplasty ; 12(7): 819-24, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9355013

RESUMEN

As accumulating evidence indicates that polyethylene plays a central role in periprosthetic osteolysis, there is a renewed interest in alternatives such as metal-metal bearings. Several long-term studies report encouraging results with the McKee-Farrar total hip arthroplasty, but there is a paucity of data on the incidence, severity, and pathogenesis of osteolysis in metal-metal bearing total hip arthroplasties. This study presents a patient who had progressive bilateral pelvic osteolysis associated with his McKee-Farrar metal-metal total hip prostheses. His left hip was revised after 13.5 years of service. The tissues revealed no gross metal staining and fewer inflammatory constituents than are typically found in metal-polyethylene bearing hips. His right hip was still functioning after 22.5 years of service, although the acetabular component was loose by that point. An arthrogram of this hip demonstrated communication of the joint with the iliac osteolysis. The development of osteolysis in both hips followed a pattern similar to that seen in metal-polyethylene total hip arthroplasties. Bearing wear could not be detected in either of the hips. Accumulating evidence indicates that particulate debris of appropriate size and number is capable of fueling periprosthetic inflammation. Specific to this study, consideration should be given to particles of cobalt-chromium alloy, polymethyl methacrylate bone-cement, and barium sulfate. Other factors that should be considered are increased joint fluid pressure, soluble inflammatory mediators, and the effective joint space. When bone becomes part of the effective joint space, it is exposed to particulate debris, soluble factors, and potentially increased joint fluid pressures, which may promote localized bone resorption. It must be kept in mind that the development of osteolysis is multifactorial. Although bearings with better wear characteristics are desirable, the elimination of polyethylene will not eliminate osteolysis.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Aleaciones de Cromo/efectos adversos , Prótesis de Cadera , Osteólisis/etiología , Complicaciones Posoperatorias , Necrosis de la Cabeza Femoral/cirugía , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/cirugía , Diseño de Prótesis , Falla de Prótesis
6.
Thorax ; 54(2): 141-4, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10325919

RESUMEN

BACKGROUND: In order to study the impact on the lung function of patients with cystic fibrosis of the avidity of antipseudomonal antibodies, the avidity of antibodies against the chromosomal beta-lactamase of Pseudomonas aeruginosa (a beta ab) and against the 60-65 kDa heat shock protein of P aeruginosa (anti-GroEL) were measured in serum samples collected longitudinally during chronic infection with P aeruginosa from a group of patients with poor and good lung function. METHODS: The thiocyanate elution method in which the molarity of potassium thiocyanate required to elute 50% bound antibody under conditions of antigen excess in ELISA was used to measure the relative avidity. RESULTS: All patients developed increasing levels of a beta ab and anti-GroEL antibodies during the follow up period but no maturation of the avidity of these antibodies was observed. In patients with good lung function the avidity of a beta ab was higher than in patients with poor lung function (p = 0.018). No significant difference in the avidity of the anti-GroEL antibodies was observed between the two groups of patients. CONCLUSION: In patients with cystic fibrosis a high avidity of a beta ab could contribute to a more efficient inhibition of the beta-lactamase by these antibodies, resulting in the better lung function seen in this group. The immunopathological implication of the failure in avidity maturation of antibodies in chronic infection is discussed.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Afinidad de Anticuerpos , Fibrosis Quística/inmunología , Pseudomonas aeruginosa/inmunología , Enfermedad Crónica , Fibrosis Quística/microbiología , Fibrosis Quística/fisiopatología , Ensayo de Inmunoadsorción Enzimática , Volumen Espiratorio Forzado/fisiología , Proteínas de Choque Térmico/inmunología , Humanos , Inmunoglobulina G/inmunología , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/fisiopatología , Capacidad Vital/fisiología
7.
Thorax ; 51(7): 733-8, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8882082

RESUMEN

BACKGROUND: Antibodies against chromosomal beta-lactamase of Pseudomonas aeruginosa (a beta ab) are markers of the development of resistance of P aeruginosa to beta-lactam antibiotics in patients with cystic fibrosis and chronic lung infection. The role of these antibodies in patients with chronic lung infection with P aeruginosa was further investigated by correlating the a beta ab IgG subclasses with pulmonary function in patients with cystic fibrosis. METHODS: Immunoglobulin G (IgG) and IgG subclass a beta ab were investigated by western blotting and quantified by laser scanning densitometry. A longitudinal study on 43 consecutive patients with cystic fibrosis who developed chronic lung infection with P aeruginosa was performed. RESULTS: IgG subclass a beta ab appeared in all patients with chronic infection with P aeruginosa. Eleven years after the onset of infection all the patients had IgG1, 79% had IgG4, 56% IgG2, and only 16% of the patients had IgG3 a beta ab. The IgG1 and IgG4 a beta ab appeared first, and more than 50% of the patients were IgG1 and IgG4 a beta ab positive within 2-3 years of the onset of infection, but IgG2 positivity only appeared after seven years and IgG3 remained absent from most of the patients. The median a beta ab levels increased during chronic infection: 100-fold for IgG1, 22-fold for IgG2, and 45-fold for IgG4. A 16-fold increase in the IgG3 a beta ab levels was detected in the six patients who developed IgG3 a beta ab. In the first four years of the chronic infection the a beta ab titres were higher in patients with good lung function than in those with poor lung function. CONCLUSIONS: The association of a weak IgG3 and a strong IgG4 a beta ab response suggests that the contribution of a beta ab antibodies to lung diseases mediated by immune complexes might be less important than other antipseudomonal antibodies. A beneficial neutralising effect of the a beta ab antibodies on the antibiotic destroying enzymes may be an additional factor.


Asunto(s)
Fibrosis Quística/microbiología , Inmunoglobulina G/sangre , Infecciones por Pseudomonas/enzimología , Pseudomonas aeruginosa , beta-Lactamasas/inmunología , Adolescente , Adulto , Antibacterianos , Western Blotting , Niño , Preescolar , Enfermedad Crónica , Fibrosis Quística/complicaciones , Fibrosis Quística/inmunología , Densitometría , Farmacorresistencia Microbiana , Humanos , Lactante , Estudios Longitudinales , Persona de Mediana Edad , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/inmunología , Pruebas de Función Respiratoria , beta-Lactamas
8.
Diabetes Res ; 7(4): 171-8, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2900090

RESUMEN

Somatostatin has been widely employed in studies of hepatic metabolism to suppress the endogenous secretion of the pancreatic hormones, insulin and glucagon. The possibility of somatostatin having hepatic effects has been considered before, but not decisively demonstrated. Eleven anesthetized dogs were used to assess the effect of somatostatin on hepatic insulin extraction (HIE) and hepatic glucose production (HGP). Insulin was infused by peripheral vein alone and during somatostatin (800 ng/kg/hr) in one series (I) of experiments and in the reverse sequence in another series (II). Portal vein and hepatic artery blood flow were measured electromagnetically, and blood samples were taken from the hepatic artery, portal vein, hepatic vein and a peripheral vein. HIE was increased in the presence of insulin plus somatostatin infusion. The combined results in Series I and II were 72.0 +/- 3.0% compared in insulin alone (64.0 +/- 4.0%, p less than 0.01). HGP was decreased in the presence of insulin and somatostatin infusion compared to insulin infusion alone both in Series I and II (1.71 +/- 0.25 to 3.72 +/- 4.0%, combined results, p less than 0.01). Whether this reduction in HGP indicates a direct effect of somatostatin on the liver, in addition to the inhibition of glucagon secretion, remains to be clarified. However, a decrease in hepatic glucose production is consistent with increased insulin extraction during somatostatin observed in the present study. We conclude that somatostatin increases the hepatic extraction of exogenous insulin. This effect of somatostatin is associated with decreased hepatic glucose production.


Asunto(s)
Glucosa/metabolismo , Insulina/metabolismo , Hígado/metabolismo , Somatostatina/farmacología , Animales , Glucemia/metabolismo , Perros , Insulina/sangre , Cinética , Hígado/efectos de los fármacos , Valores de Referencia
9.
Clin Orthop Relat Res ; (329 Suppl): S48-59, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8769322

RESUMEN

Clinical and radiographic evaluations of 15 McKee-Farrar hip replacements in 13 patients with followup of 21 to 26 years were performed. The average Harris hip score was 86 with no patients having a poor result. These patients outscored the age matched controls in all categories of the SF-36 health survey. All patients were community ambulators with qualitative activity levels exceeding the average for their age. Quantitative activity assessment with a pedometer in 3 patients indicated a current average of approximately 900,000 cycles per year. This represents more than 21 million cycles when extrapolated during the life of the implants. None of the femoral components were radiographically loose. One acetabular component may be loose. Osteolysis developed in 3 apparently well fixed femurs and in 1 acetabulum. There were several features of these cases that may have contributed to the long survival: (1) relatively small stature of the patients who averaged 160.5 cm (5 feet 5 inches) in height and 66.9 kg (147 lbs) in weight; (2) favorable biomechanics of the reconstruction with the hip center of rotation being medialized by an average of 6.4 mm and the femoral offset increased by an average of 4.9 mm; (3) decreased potential for neck socket impingement with an average lateral acetabular opening of 54 degrees and all components were anteverted; (4) radiolucent cement in 13 of 15 hips; and (5) no radiographically measurable wear. Previous analyses and comparisons of the clinical performance of the McKee-Farrar implant have focused on the metal on metal bearing. As has been recognized with the many variations of total hip replacement using metal on plastic hearings, there are a myriad of variables that contribute to clinical outcome. The results of this study suggest that patient selection and technical factors may contribute to the long term survival, and conversely to the failure, of McKee-Farrar implants.


Asunto(s)
Prótesis de Cadera , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiología , Humanos , Masculino , Metales/efectos adversos , Persona de Mediana Edad , Osteólisis/etiología , Diseño de Prótesis , Radiografía , Rango del Movimiento Articular
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