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1.
J Clin Microbiol ; 50(7): 2250-4, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22553237

RESUMEN

A new commercially available universal 16S and 18S rRNA gene PCR test, which is followed by sequence analysis of amplicons (SepsiTest), was evaluated for rapid identification of pathogens in the diagnosis of bone and joint infections. Eighty-three orthopedic samples and 21 specimens from other normally sterile body sites collected from 84 patients were analyzed in parallel by culture and PCR for detection of bacteria and fungi. Compared to culture, the diagnostic sensitivity and specificity of PCR were 88.5% and 83.5%, respectively. The detection rate of PCR (34.6%) was higher than that of bacterial culture (25.0%) as a consequence of the presence of fastidious and noncultivable species in samples and antibiotic treatment of patients. Thirteen culture-negative infections were identified by PCR, and PCR was able to detect culture-proven polymicrobial infections. On the other hand, three samples were culture positive but PCR negative. SepsiTest was demonstrated to be a valuable supplemental tool in the rapid detection of bacteria, especially for fastidious and noncultivable organisms, allowing earlier initiation of pathogen-adapted therapy in patients with bone and joint infections.


Asunto(s)
Bacterias/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Osteoartritis/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia/métodos , Bacterias/genética , Infecciones Bacterianas/microbiología , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Humanos , Osteoartritis/microbiología , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad
2.
Eur J Gynaecol Oncol ; 33(3): 265-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22873096

RESUMEN

OBJECTIVE: To determine the utility of a modified version of ovarian cancer-focused cancer risk evaluation and early detection (CADET) scores as a screening tool for ultrasonographic ovarian findings. STUDY DESIGN: Prospective pilot study. MAIN OUTCOME MEASURES: CADET scores were compared with abnormal ultrasonographic ovarian findings of peri- and postmenopausal women who attended their gynecologist for a routine check-up. The women filled in the CADET questionnaire before seeing their gynecologists who were blinded to the CADET results. The women whom they referred for pelvic transvaginal ultrasonographic examination comprised the study group. The results of their scans were compared with their CADET scores. RESULTS: Of the 181 peri- and postmenopausal women who were candidates for this study, 154 were referred for ultrasonography, of whom 38 (24%, Group A) had abnormal ovarian scans (30 simple cysts and 8 complex findings). The other 116 (76%) women had normal sonograms (Group B). Demographic characteristics were similar for both groups. Thirteen Group A women (34%) and 52 Group B women (45%) had positive CADET scores (p = NS). The average group CADET scores were also not significantly different (0.8 +/- 1.7 for Group A and 1.7 +/- 2.5 for Group B). CONCLUSION: CADET scores did not correlate with abnormal ultrasonographic ovarian findings.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Ováricas/diagnóstico , Encuestas y Cuestionarios , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico por imagen , Perimenopausia , Proyectos Piloto , Posmenopausia , Valor Predictivo de las Pruebas , Medición de Riesgo , Método Simple Ciego , Ultrasonografía
3.
Protein Sci ; 26(7): 1303-1313, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28470684

RESUMEN

RNA polymerase (RNAP) is the central motor of gene expression since it governs the process of transcription. In prokaryotes, this holoenzyme is formed by the RNAP core and a sigma factor. After approaching and binding the specific promoter site on the DNA, the holoenzyme-promoter complex undergoes several conformational transitions that allow unwinding and opening of the DNA duplex. Once the first DNA basepairs (∼10 bp) are transcribed in an initial transcription process, the enzyme unbinds from the promoter and proceeds downstream along the DNA while continuously opening the helix and polymerizing the ribonucleotides in correspondence with the template DNA sequence. When the gene is transcribed into RNA, the process generally is terminated and RNAP unbinds from the DNA. The first step of transcription-initiation, is considered the rate-limiting step of the entire process. This review focuses on the single-molecule studies that try to reveal the key steps in the initiation phase of bacterial transcription. Such single-molecule studies have, for example, allowed real-time observations of the RNAP target search mechanism, a mechanism still under debate. Moreover, single-molecule studies using Förster Resonance Energy Transfer (FRET) revealed the conformational changes that the enzyme undergoes during initiation. Force-based techniques such as scanning force microscopy and magnetic tweezers allowed quantification of the energy that drives the RNAP translocation along DNA and its dynamics. In addition to these in vitro experiments, single particle tracking in vivo has provided a direct quantification of the relative populations in each phase of transcription and their locations within the cell.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/química , ADN/química , Transferencia Resonante de Energía de Fluorescencia/métodos , ARN/biosíntesis , Iniciación de la Transcripción Genética/fisiología , ADN/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , ARN/química
4.
Arch Intern Med ; 145(10): 1815-7, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4037942

RESUMEN

Blood gas and serum electrolyte levels were measured in 27 elderly patients (mean age +/- SD, 63.3 +/- 13.5 years) who were receiving acetazolamide (250 to 1,000 mg/day) for glaucoma. Eleven glaucomatous patients (mean age, 69.1 +/- 7.4 years) who were not receiving acetazolamide served as a control group. In the acetazolamide-treated group, four patients (14.8%) had mild acidosis (7.29 greater than pH less than or equal to 7.31), ten (37%) had moderate acidosis (7.20 greater than pH less than or equal to 7.29), and one patient (3.7%) had severe acidosis (pH, 7.15). None of the patients in the control group had acidosis. It is concluded that moderate metabolic acidosis of potential clinical significance is common among glaucomatous elderly patients who receive acetazolamide. The exact clinical significance of our observations is yet to be determined.


Asunto(s)
Acetazolamida/efectos adversos , Acidosis/inducido químicamente , Acetazolamida/uso terapéutico , Acidosis/sangre , Anciano , Bicarbonatos/sangre , Cloruros/sangre , Femenino , Glaucoma de Ángulo Abierto/tratamiento farmacológico , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad
5.
Neurology ; 28(1): 8-17, 1978 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-201886

RESUMEN

We report six cases of inclusion body myositis (IBM), a distinct but infrequently recognized inflammatory disease of skeletal muscle. Clinically, IBM differs from dermatomyositis and polymyositis. It lacks features of collagen-vascular disease, has a relatively benign and protracted course, frequently involves distal muscles, is found mainly in males, and does not improve with corticosteroid treatment. Electronmicroscopic demonstration of abnormal filaments in muscle cells is necessary for definite diagnosis, but IBM may be suspected by the finding on cryostat sections of numerous hematoxylinophilic granules in "lined" vacuoles in muscle cells. These correspond to whorls of cytomembranes. Although in dermatomyositis the capillary network is partly destroyed, in IBM it is usually augmented. A viral etiology of IBM has been suggested but remains unproven.


Asunto(s)
Cuerpos de Inclusión/ultraestructura , Miositis/patología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos/ultraestructura , Miositis/diagnóstico , Pronóstico
6.
Thromb Haemost ; 59(2): 221-4, 1988 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-3388295

RESUMEN

Between 1981 and 1986, we evaluated 59 patients who presented with isolated prolongation of bleeding time with normal platelet counts, platelet aggregation and coagulation parameters (including von Willebrand's factor), and without evidence of liver or kidney disease, or exposure to anti-platelet agents. These patients, termed as vascular fragility syndrome (VFS), were analyzed to further characterize their bleeding patterns. The pattern of bleeding manifestations was similar to that of patients with platelet dysfunction, such as mucocutaneous bleeding or excessive post-operative bleeding. In 16 patients, desmopressin (1-desamino-8-d-arginine vasopressin, DDAVP) was infused to control active bleeding or as a part of pre-surgical evaluation. Bleeding time improved (pre-DDAVP bleeding time 15.3 +/- 3.4 min, mean +/- S.D.; post-DDAVP bleeding time 10.7 +/- 3.9 min; p less than 0.01) within 30 minutes following the DDAVP infusion with either satisfactory arrest of acute bleeding or good control of subsequent hemostasis with surgery. Side effects with DDAVP were transient and minor, i.e. facial flushing, or conjunctival erythema. These findings indicate that VFS with isolated prolongation of bleeding time is a frequently encountered bleeding disorder and that DDAVP is effective in achieving hemostasis for the management of acute bleeding and may be useful prior to surgical procedures.


Asunto(s)
Desamino Arginina Vasopresina/uso terapéutico , Trastornos Hemorrágicos/tratamiento farmacológico , Tiempo de Sangría , Desamino Arginina Vasopresina/administración & dosificación , Femenino , Trastornos Hemorrágicos/sangre , Trastornos Hemorrágicos/genética , Hemostasis/efectos de los fármacos , Humanos , Infusiones Intravenosas , Masculino , Linaje
7.
Chest ; 111(5): 1446-7, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9149610

RESUMEN

A case of amiodarone pulmonary toxicity (APT) occurring within days of the start of therapy and presenting with hemoptysis is reported. Both the very early onset and the presenting symptom are highly unusual in this entity. Implications in the diagnosis of APT are discussed.


Asunto(s)
Amiodarona/efectos adversos , Antiarrítmicos/efectos adversos , Hemoptisis/inducido químicamente , Pulmón/efectos de los fármacos , Enfermedad Aguda , Anciano , Fibrilación Atrial/tratamiento farmacológico , Tos/inducido químicamente , Disnea/inducido químicamente , Fiebre/inducido químicamente , Humanos , Pulmón/patología , Masculino , Factores de Tiempo
8.
Chest ; 115(6): 1593-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10378554

RESUMEN

BACKGROUND: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. OBJECTIVE: To determine the clinical outcome and the long-term results of a second CABG. SETTING: An 1100-bed urban university-affiliated hospital. DESIGN: Retrieval of data on selected parameters from medical records before surgery and prospective follow-up afterwards. PATIENTS AND METHODS: We studied the outcomes of 498 consecutive patients who underwent CABG reoperation in our institution from January 1978 to December 1989 and who were followed postoperatively. Their perioperative mortality, morbidity, and long-term follow-up results were re-evaluated. The end points of the study were December 1997, 15 years of follow-up, or the patient's death. RESULTS: The perioperative mortality rate was 3%. The cumulative survival rates were 90.1%, 74%, and 63.4% at the 5-year, 10-year, and 15-year follow-ups, respectively. The cardiac event-free survival rates were 91.5%, 83.4%, and 67.8% at the 5-year, 10-year, and 15-year follow-ups, respectively. The risk factors adversely affecting long-term survival were advanced age, hypertension, and a low left ventricular ejection fraction (LVEF). CONCLUSIONS: The long-term results of cumulative survival and cardiac event-free survival in patients who underwent CABG reoperation are good. Although this reoperation is safe overall, advanced age, hypertension, and a decreased LVEF significantly increase the surgical risk.


Asunto(s)
Puente de Arteria Coronaria , Oclusión de Injerto Vascular/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Puente de Arteria Coronaria/mortalidad , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/cirugía , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/mortalidad , Oclusión de Injerto Vascular/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Reoperación/mortalidad , Factores de Riesgo , Volumen Sistólico , Tasa de Supervivencia
9.
Chest ; 120(2): 674-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502679

RESUMEN

Two patients with subacute symptoms and signs compatible with pulmonary tuberculosis (TB) had right upper lobe cavitary infiltrates shown on chest radiography. In both patients, purified protein derivative and microbiologic testing excluded TB, and tissue examination yielded typical histologic changes of bronchiolitis obliterans organizing pneumonia (BOOP). Glucocorticoid therapy led to clinical and radiologic resolution. Though probably rare in this situation, BOOP should be considered in the differential diagnosis of patients presenting with clinical and radiologic features of pulmonary TB.


Asunto(s)
Neumonía en Organización Criptogénica/diagnóstico , Tuberculosis Pulmonar/diagnóstico , Anciano , Neumonía en Organización Criptogénica/tratamiento farmacológico , Diagnóstico Diferencial , Humanos , Masculino , Prednisona/uso terapéutico , Radiografía Torácica , Tomografía Computarizada por Rayos X
10.
Ann Thorac Surg ; 64(2): 473-7, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9262596

RESUMEN

BACKGROUND: The immediate benefits of coronary artery bypass grafting might be only transient. This prospective study examined the capability of exercise radionuclide cineangiography done shortly after coronary artery bypass grafting to predict outcome and long-term prognosis. METHODS: Results of exercise radionuclide cineangiography at 5.5 +/- 0.7 months (range, 4 to 8 months) postoperatively were correlated with mortality, major surgical and nonsurgical cardiac events, and cardiac event-free survival in 100 consecutive patients who underwent coronary artery bypass grafting. Stepwise logistic regression analysis was used to evaluate the incremental value of radionuclide cineangiography beyond the commonly used variables. RESULTS: Left ventricular ejection fraction at rest was normal (> or = 0.45) in 72 patients and increased on exercise in 58. The exercise radionuclide variables that correlated with future cardiac events were change and fractional change in heart rate, ST segment changes, anginal pain and congestive heart symptoms during exercise, rest ejection fraction, and change and fractional changes in ejection fraction. Predictors of event-free survival were exercise heart rate, rest ejection fraction, and change and fractional change in ejection fraction during exercise. Logistic regression analysis revealed that change in ejection fraction was an independent predictor of cardiac death and surgical interventions, whereas resting ejection fraction was a predictor of nonsurgical cardiac events. CONCLUSIONS: Postoperative exercise radionuclide cineangiography carried out soon after coronary artery bypass grafting had definite independent prognostic value and should be performed routinely to help decide treatment protocol.


Asunto(s)
Puente de Arteria Coronaria , Prueba de Esfuerzo , Angiografía por Radionúclidos , Adulto , Anciano , Anciano de 80 o más Años , Puente de Arteria Coronaria/mortalidad , Humanos , Persona de Mediana Edad , Análisis Multivariante , Complicaciones Posoperatorias , Periodo Posoperatorio , Pronóstico , Estudios Prospectivos , Análisis de Regresión , Volumen Sistólico , Resultado del Tratamiento , Función Ventricular Izquierda
11.
Int J Antimicrob Agents ; 24(4): 401-4, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15380269

RESUMEN

We investigated the in vitro synergistic antifungal potential of combining serotonin (5-HT) and sertraline with amphotericin B and itraconazole against clinical isolates of Aspergillus spp. Synergy tests were performed using the chequerboard microdilution method. Activity was measured against Aspergillus fumigatus (n = 7), Aspergillus flavus (n = 3) and Aspergillus terreus (n = 2), and compared with that for Candida albicans and Candida parapsilosis. The fractional inhibitory concentration (FIC) indices ranged between 0.25 and 3 for the various isolates tested. 5-HT was shown to enhance the activity of amphotericin B against Aspergillus spp. Combination studies with 5-HT and itraconazole and with sertraline and itraconazole or amphothericin B showed different activities for the various strains, including synergism (FIC < 1.0), additivity (FIC = 1), and indifference (FIC between 1.0 and 2.0). 5-HT and sertraline showed antagonistic activity (FIC > 2) with amphotericin B and itraconazole against C. parapsilosis.


Asunto(s)
Anfotericina B/farmacología , Aspergillus fumigatus/efectos de los fármacos , Serotonina/farmacología , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Candida albicans/efectos de los fármacos , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana
12.
Artículo en Inglés | MEDLINE | ID: mdl-1118043

RESUMEN

Rat brain homogenate and synaptosomes from rat brain bind botulinum toxin. The binding is accompanied by partial inactivation. The binding decreases with increasing ionic strength. A considerable fixation of tetanus toxin can still be demonstrated under conditions which prevent the fixation of botulinum toxin. 2. Only the grey substance, not the white substance from bovine brain is able to bind the toxin. 3. Upon pretreatment with neuraminidase, synaptosomes lose nearly all of their binding capacity. However, neither gangliosides nor ganglioside-cerebroside mixtures nor brain extracts could replace the synaptosomes. Thus botulinum A toxin closely resembles tetanus toxin in its ability to react with (a) neuraminidase-sensitive site(s) of the grey matter of the CNS. It differs from tetanus toxin by its stronger sensitivity against ionic forces and by its failure to react with certain gangliosides.


Asunto(s)
Toxinas Botulínicas/metabolismo , Encéfalo/metabolismo , Animales , Sitios de Unión , Toxinas Botulínicas/toxicidad , Encéfalo/ultraestructura , Bovinos , Centrifugación , Eritrocitos/metabolismo , Gangliósidos/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Ratones , Neuraminidasa/metabolismo , Unión Proteica , Ratas , Esfingolípidos/metabolismo , Sinaptosomas/metabolismo , Toxina Tetánica/metabolismo
13.
Clin Exp Rheumatol ; 7(3): 301-3, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2758710

RESUMEN

A young female patient who had documented seropositive rheumatoid arthritis and was treated consecutively with aspirin, diclofenac, and gold salts was admitted years later for severe neutropenia. On examination she had, in addition, fever, positive rheumatoid factor, reversible swan-neck deformity of the fingers but otherwise normal joint findings. The patient responded to prednisone therapy. This case would appear to be a most unusual variant of Felty's syndrome.


Asunto(s)
Síndrome de Felty/complicaciones , Adulto , Artritis Reumatoide/complicaciones , Artritis Reumatoide/tratamiento farmacológico , Síndrome de Felty/diagnóstico por imagen , Síndrome de Felty/tratamiento farmacológico , Femenino , Mano/diagnóstico por imagen , Humanos , Recuento de Leucocitos/efectos de los fármacos , Registros Médicos , Neutropenia/tratamiento farmacológico , Neutropenia/patología , Neutrófilos/patología , Prednisona/uso terapéutico , Radiografía
14.
Clin Rheumatol ; 19(4): 321-3, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10941818

RESUMEN

Myasthenia gravis (MG) and polymyositis (PM) are organ-specific autoimmune diseases. Occasional reports describe patients with clinical and pathologic features of both. Achalasia is idiopathic in nature, but autoimmune and inflammatory mechanisms have been proposed for this disorder as well. We describe a patient with dysphagia who was diagnosed at different points in time with all these three rare conditions. Despite at least putatively having immune mechanisms in common, an association between the three has not been previously described.


Asunto(s)
Trastornos de Deglución/etiología , Acalasia del Esófago/complicaciones , Miastenia Gravis/complicaciones , Polimiositis/complicaciones , Anciano , Antiinflamatorios/uso terapéutico , Biopsia , Trastornos de Deglución/diagnóstico , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Inmunosupresores/uso terapéutico , Metotrexato/uso terapéutico , Músculos/patología , Miastenia Gravis/diagnóstico , Polimiositis/diagnóstico , Polimiositis/tratamiento farmacológico , Polimiositis/patología , Prednisona/uso terapéutico , Factores de Tiempo
15.
Neth J Med ; 62(8): 290-2, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15588070

RESUMEN

A healthy 28-year-old woman developed full-blown pulmonary oedema in the 36th week of gestation. Echocardiography revealed a globally enlarged heart with reduced systolic function. A remarkable dinical response with regain of normal ventricular function was noted with early medical intervention. This case report illustrates peripartum cardiomyopathy, a unique form of dilated cardiomyopathy affecting women during/following gestation. Clinician familiarity with this entity increases the probability of prompt appropriate treatment, offering patients the best possible prognosis.


Asunto(s)
Cardiomiopatía Dilatada/diagnóstico por imagen , Insuficiencia Cardíaca/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/diagnóstico , Adulto , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/etiología , Diagnóstico Diferencial , Ecocardiografía , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/etiología , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Tercer Trimestre del Embarazo
16.
Methods Inf Med ; 38(3): 182-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10522121

RESUMEN

Previously undescribed algebraic transforms of Bayes' theorem define families of operating points in the receiver operating characteristic (ROC) space which, at given pre-test probability, produce constant post-test probabilities. These isopredictive operating points form straight lines in the ROC space. The lines can be used to emulate Bayesian sequential analysis in a strictly graphic procedure, which can be applied in clinical work and medical education.


Asunto(s)
Teorema de Bayes , Gráficos por Computador , Valor Predictivo de las Pruebas , Curva ROC , Técnicas de Apoyo para la Decisión , Humanos
17.
Methods Inf Med ; 34(3): 259-65, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7666804

RESUMEN

New classification criteria for vasculitic disorders have recently been proposed by the American College of Rheumatology. These classification criteria have limitations inherent to the method employed in their development. We propose a different approach to the quantitative analysis of the manifestations of vasculitis, which may improve the precision of classification criteria in this domain. Bayesian classifiers were developed for six vasculitides using literature-derived quantitative descriptions of these syndromes. These clinical data were also used in computer programs designed to generate simulations of vasculitis and control cases. The performance of Bayesian classifiers of vasculitis was then compared to that of the American College of Rheumatology criteria, using series of computer-simulated vasculitis cases. Bayesian classifiers identified simulated vasculitis cases with greater accuracy than those of the corresponding American College of Rheumatology 1990 vasculitis criteria in all six diseases studied. As predicted by theoretical considerations, Bayesian classifiers have the potential to identify vasculitis cases more accurately than the proposed American College of Rheumatology 1990 criteria.


Asunto(s)
Teorema de Bayes , Simulación por Computador , Vasculitis/clasificación , Adolescente , Adulto , Técnicas de Apoyo para la Decisión , Diagnóstico por Computador , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Síndrome , Vasculitis/diagnóstico
18.
Adv Exp Med Biol ; 107: 489-95, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-33542

RESUMEN

An assay procedure for streptococcal IgA protease is described which uses isotopically labelled human serum IgA as substrate. Enzyme activity was monitored by the radioactive counts in the Fab alpha product, which was separated from other components in the digestion mixture by electrophoresis. Cleavage of IgA was linear with respect to time using catalytic amounts of the enzyme. Km was calculated to be 5.5 X 10(-6)M, pH optimum 6.0-7.0 at 37 degrees C, and the enzyme was fully inactivated at low concentrations of the metal chelator ethylenediaminetetraacetic acid.


Asunto(s)
Inmunoglobulina A/metabolismo , Péptido Hidrolasas/metabolismo , Streptococcus sanguis/enzimología , Ácido Edético/farmacología , Concentración de Iones de Hidrógeno , Cinética , Métodos , Proteínas de Mieloma/metabolismo , Péptido Hidrolasas/análisis , Inhibidores de Proteasas
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