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1.
J Reconstr Microsurg ; 38(2): 151-159, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34404104

RESUMEN

BACKGROUND: Distal lower extremity reconstruction can be challenging in terms of flap design. Bulky flaps result in limited mobility accompanied with the need of customized footwear. Raising the ALT-flap in a superficial fascial plane (thin ALT-flap) can be beneficial. This study evaluates thin ALT-flaps for lower distal extremity reconstruction. METHODS: In a retrospective study, patients that underwent microvascular extremity reconstruction at the level of the ankle and dorsal foot at the University of Freiburg from 2008-2018 were reviewed. RESULTS: 95 patients could be included in the study (35 perforator flaps, 8 fascia flaps and 54 muscle flaps).Among the perforator flaps, 21 ALT-flaps were elevated conventionally and 14 in the superficial fascial plane (thin ALT-flap). Among the conventional ALT-flaps, there was one flap loss (5%) and one successful revision (5%). 5(24%) flaps received secondary thinning. 57%(n = 12) were able to wear conventional footwear. There were 2(15%) successful revisions of thin ALT-flaps. 100% of thin ALT-flaps survived and 85%(n = 11) of the patients wore ordinary footwear after defect coverage.Among fascial flaps, 50%(n = 4) had to be revised with 2(25%) complete and 1 (13%) partial flap loss. All patients achieved mobility in ordinary shoes (n = 8).In muscle flaps, there were 7(13%) revisions and 5(9%) flap losses. 5(9%) flaps received secondary thinning. Only 33%(n = 18) were mobile in ordinary footwear. CONCLUSION: The thin ALT-flap is a save one-stage evolution for lower distal extremity reconstruction with a favorable flap survival rate. Compared with conventional ALT-flaps it might be beneficial in reducing the need for expensive custom fitted shoes and secondary thinning procedures.


Asunto(s)
Colgajo Perforante , Procedimientos de Cirugía Plástica , Tobillo/cirugía , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
3.
Mediators Inflamm ; 2015: 372432, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26089599

RESUMEN

C-reactive protein (CRP) is a pentraxin that has long been employed as a marker of inflammation in clinical practice. Recent findings brought up the idea of CRP to be not only a systemic marker but also a mediator of inflammation. New studies focused on structural changes of the plasma protein, revealing the existence of two distinct protein conformations associated with opposed inflammatory properties. Native, pentameric CRP (pCRP) is considered to be the circulating precursor form of monomeric CRP (mCRP) that has been identified to be strongly proinflammatory. Recently, a dissociation mechanism of pCRP has been identified on activated platelets and activated/apoptotic cells associated with the amplification of the proinflammatory potential. Correspondingly, CRP deposits found in inflamed tissues have been identified to exhibit the monomeric conformation by using conformation-specific antibodies. Here we review the current literature on the causal role of the dissociation mechanism of pCRP and the genesis of mCRP for the amplification of the proinflammatory potential in inflammatory reactions such as atherosclerosis and ischemia/reperfusion injury. The chance to prevent the formation of proinflammatory mediators in ubiquitous inflammatory cascades has pushed therapeutic strategies by targeting pCRP dissociation in inflammation. In this respect, the development of clinically applicable derivatives of the palindromic compound 1,6-bis(phosphocholine)-hexane (1,6-bis PC) should be a major focus of future CRP research.


Asunto(s)
Proteína C-Reactiva/química , Proteína C-Reactiva/metabolismo , Inflamación/metabolismo , Animales , Proteína C-Reactiva/genética , Hexanos/química , Humanos , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Conformación Proteica
4.
Pneumologie ; 67(3): 150-156, 2013 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-23424035

RESUMEN

Sleep-disordered breathing (SDB) constitutes a highly prevalent comorbidity in patients with chronic heart failure (HF, approximately 45%). Both diseases are related in a bidirectional way: Obstructive sleep apnoea (OSA) can contribute to the development of HF via multiple mechanisms. Apnoea-related acute rise of cardiac afterload as well as manifest hypertension may contribute to the development of myocardial hypertrophy and thus HF. In addition, OSA increases the risk for myocardial infarction and impaired recovery of cardiac function after the event. Impaired cardiac function itself may contribute to the development of obstructive and central sleep apnoea (SA). Therefore, optimal medical management of HF is part of the therapy of SDB in such patients. Treatment of SDB with different modes of positive airway pressure suppresses apnoeas and hypopnoeas, improves sleep and may improve related symptoms and cardiac function of affected patients. Considering the high coincidence of SDB and HF, the adequate diagnosis of SDB and evaluation of indication for therapy of SDB performed in a specialised centre is advised.


Asunto(s)
Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/terapia , Infarto del Miocardio/epidemiología , Infarto del Miocardio/terapia , Respiración con Presión Positiva/estadística & datos numéricos , Síndromes de la Apnea del Sueño/epidemiología , Síndromes de la Apnea del Sueño/terapia , Causalidad , Enfermedad Crónica , Comorbilidad , Insuficiencia Cardíaca/diagnóstico , Humanos , Infarto del Miocardio/diagnóstico , Prevalencia , Factores de Riesgo , Síndromes de la Apnea del Sueño/diagnóstico
5.
Pharmacol Ther ; 235: 108165, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35247517

RESUMEN

C-reactive protein (CRP) is the prototypic acute-phase reactant that has long been recognized almost exclusively as a marker of inflammation and predictor of cardiovascular risk. However, accumulating evidence indicates that CRP is also a direct pathogenic pro-inflammatory mediator in atherosclerosis and cardiovascular diseases. The 'CRP system' consists of at least two protein conformations with distinct pathophysiological functions. The binding of the native, pentameric CRP (pCRP) to activated cell membranes leads to a conformational change resulting in two highly pro-inflammatory isoforms, pCRP* and monomeric CRP (mCRP). The deposition of these pro-inflammatory isoforms has been shown to aggravate the localized tissue injury in a broad range of pathological conditions including atherosclerosis and thrombosis, myocardial infarction, and stroke. Here, we review recent findings on how these structural changes contribute to the inflammatory response and discuss the transitional changes in the structure of CRP as a novel therapeutic target in cardiovascular diseases and overshooting inflammation.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Proteína C-Reactiva/química , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/tratamiento farmacológico , Humanos , Inflamación/metabolismo , Conformación Proteica , Isoformas de Proteínas/metabolismo
6.
Behav Brain Res ; 396: 112883, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-32860830

RESUMEN

Recent animal and human studies highlight the uncertainty about the onset of an aversive event as a crucial factor for the involvement of the centromedial amygdala (CM) and bed nucleus of the stria terminalis (BNST) activity. However, studies investigating temporally predictable or unpredictable threat anticipation and confrontation processes are rare. Furthermore, the few existing fMRI studies analyzing temporally predictable and unpredictable threat processes used small sample sizes or limited fMRI paradigms. Therefore, we measured functional brain activity in 109 predominantly female healthy participants during a temporally predictable-unpredictable threat paradigm, which aimed to solve limited aspects of recent studies. Results showed higher BNST activity compared to the CM during the cue indicating that the upcoming confrontation is aversive relative to the cue indicating an upcoming neutral confrontation. Both the CM and BNST showed higher activity during the confrontation with unpredictable and aversive stimuli, but the reaction to aversive confrontation relative to neutral confrontation was stronger in the CM compared to the BNST. Additional modulation analyses by NPSR1 rs324981 genotype revealed higher BNST activity relative to the CM in unpredictable anticipation relative to predictable anticipation in T-carriers compared to AA carriers. Our results indicate that during the confrontation with aversive or neutral stimuli, temporal unpredictability modulates CM and BNST activity. Further, there is a differential activity concerning threat processing, as BNST is more involved when focussing on fear-related anticipation processes and CM is more involved when focussing on threat confrontation.


Asunto(s)
Amígdala del Cerebelo/fisiología , Anticipación Psicológica/fisiología , Mapeo Encefálico , Miedo/fisiología , Núcleos Septales/fisiología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Receptores Acoplados a Proteínas G/genética , Factores de Tiempo , Adulto Joven
7.
Clin Anat ; 23(3): 304-11, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20169611

RESUMEN

Current surgical assumptions identify the lateral femoral cutaneous nerve (LFCN) running just under the inguinal ligament two fingerbreadths medial to the anterior superior iliac spine (ASIS). On the basis of the increasing incidence of Meralgia Paresthetica associated with various surgical procedures, it is clear that surgeons are relying on an inadequate description of the nerve's course. This study provides a better understanding of the variability of the LFCN with regards to its relationship to the ASIS and the depth at which it passes deep to the inguinal ligament. A total of 35 bodies were examined yielding 65 sets of data. Dissections were performed on 26 formalin fixed cadavers and 9 fresh morgue specimens. Measurements and calculations were made with regard to the distance from the LFCN to the ASIS along the inguinal ligament, the depth of the LFCN as it crossed the inguinal ligament, and the length of the inguinal ligament. The LFCN was observed to cross the inguinal ligament 1.4 +/- 0.4 cm medial to the ASIS with a standard deviation of 1.5 cm. The LFCN traversed the inguinal ligament 1.0 +/- 0.1 cm deep to the ligament with a standard deviation of 0.6 cm. The LFCN runs approximately one fingerbreadth medial to the ASIS. The nerve may be found far more medial or lateral than expected with several distinct branching patterns. In addition, the LFCN crosses deeper to the inguinal ligament than previously described in the literature, with a high variability of depth between specimens.


Asunto(s)
Ligamentos/anatomía & histología , Piel/inervación , Muslo/inervación , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Ilion/anatomía & histología , Masculino , Persona de Mediana Edad , Valores de Referencia , Muslo/cirugía
8.
Science ; 193(4252): 496-8, 1976 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-941021

RESUMEN

An extremely high concentration of zinc in the plasma (hyperzincemia) was found in five out of seven members of one family and in two out of three second generation indiviuals, an indication that the condition is heritable. The excess zinc in the plasma appears to be bound to serum proteins, with no apparent clinical symptoms or abnormalities.


Asunto(s)
Errores Innatos del Metabolismo de los Metales/genética , Zinc/sangre , Población Negra , Huesos/metabolismo , Proteínas Portadoras/sangre , Femenino , Genes Dominantes , Cabello/metabolismo , Humanos , Masculino , Uñas/metabolismo , Linaje , Zinc/metabolismo , Zinc/orina
9.
Hum Mutat ; 29(2): 331-2, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18205193

RESUMEN

Myoclonus-dystonia (M-D) is an autosomal-dominant movement disorder caused by mutations in SGCE. We investigated the frequency and type of SGCE mutations with emphasis on gene dosage alterations and explored the associated phenotypes. We tested 35 M-D index patients by multiplex ligation-dependent probe amplification (MLPA) and genomic sequencing. Mutations were found in 26% (9/35) of the cases, all but three with definite M-D. Two heterozygous deletions of the entire SGCE gene and flanking DNA and a heterozygous deletion of exon 2 only were detected, accounting for 33% (3/9) of the mutations found. Both large deletions contained COL1A2 and were additionally associated with joint problems. Further, we discovered one novel small deletion (c.771_772delAT, p.C258X) and four recurrent point mutations (c.289C>T, p.R97X; c.304C>T, p.R102X; c.709C>T, p.R237X; c.1114C>T, p.R372X). A Medline search identified 22 articles on SGCE mutational screening. Sixty-four unrelated M-D patients were described with 41 different mutations. No genotype-phenotype association was found, except in patients with deletions encompassing additional genes. In conclusion, a rigorous clinical preselection of patients and careful accounting for non-motor signs should precede mutational tests. Gene dosage studies should be included in routine SGCE genetic testing.


Asunto(s)
Eliminación de Gen , Mioclonía/genética , Sarcoglicanos/genética , Adolescente , Adulto , Anciano , Secuencia de Bases , Niño , Preescolar , Análisis Mutacional de ADN , Demografía , Exones/genética , Femenino , Genoma Humano , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Fenotipo , Literatura de Revisión como Asunto
10.
J Clin Invest ; 76(2): 500-7, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2411759

RESUMEN

While it is well known that the engagement of IgG Fc receptors on the macrophage surface triggers a number of cellular responses, including particle ingestion, secretion, and respiratory burst activity, the mechanism of signal transmission following ligand binding remains poorly understood. To acquire more data in this area, we studied the electrical properties of the macrophage membrane and its response to oligomeric immunoglobulin G (IgG) using the patch-clamp technique on human alveolar macrophages that were obtained by bronchoalveolar lavage and maintained in short-term tissue culture. The results showed that cell resting potentials, as determined from whole-cell tight seal recordings, increased from -15 mV on the day of plating to -56 mV after the first day in culture and remained stable at this hyperpolarized level. Macrophages revealed an input resistance of 3.3 G omega, independent of age in culture. Extracellular application of heat-aggregated human IgG to cells voltage-clamped at -70 mV resulted in peak inward currents of approximately 470 pA. We identified an IgG-dependent, nonselective channel in both cell-attached and isolated membrane patches, with a unitary conductance of approximately 350 pS and a predominant subconductance level of 235 pS in symmetrical NaCl solutions. Single channel open times were observed to be in the range of seconds and, in addition, were dependent upon membrane voltage. Channel opening involved transitions between a number of kinetic states and subconductance levels. Channel events recorded in cell-attached patches showed characteristic exponential relaxations, which implied a variation in membrane potential as a result of a single ion channel opening. These data suggest that the IgG-dependent nonselective cation channel that we have characterized may provide the link between Fc receptor engagement and subsequent cellular activation.


Asunto(s)
Inmunoglobulina G/farmacología , Canales Iónicos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Alveolos Pulmonares/citología , Adulto , Membrana Celular/efectos de los fármacos , Conductividad Eléctrica/efectos de los fármacos , Electrofisiología , Femenino , Humanos , Cinética , Macrófagos/citología , Masculino , Fumar
11.
Arterioscler Thromb Vasc Biol ; 25(7): 1519-23, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15845906

RESUMEN

OBJECTIVE: Acute coronary syndromes and ischemic cerebral stroke share similarities regarding elevated platelet activation. In coronary syndromes, the importance of inflammation with platelet-leukocyte interaction has been demonstrated. Recent infection is an established risk factor for ischemic stroke; the role of platelet-leukocyte interaction in these patients had not been investigated. METHODS AND RESULTS: Using a flow cytometric assay we investigated 58 stroke patients, 21 with and 37 without infection 1 week before acute cerebral ischemia, and compared them to 58 controls with regard to platelet-leukocyte aggregation and platelet activation on admission and on day 7. Patients with previous infection were significantly up-regulated with regard to platelet activation and platelet-leukocyte aggregation compared with patients without infection. On day 7, these increases in the postinfective group had drawn level with the lower values of the other patients. As reported previously, recent infection was associated with a more severe postischemic deficit. CONCLUSIONS: These results suggest an important role of intercellular platelet-leukocyte interaction in the pathophysiology of acute cerebral ischemia which may also contribute to the increased incidence and clinical severity of ischemic stroke following infection. This may lead to therapeutic considerations of blocking intercellular adhesion molecules like P-selectin or the P-selectin glycoprotein ligand.


Asunto(s)
Plaquetas/citología , Comunicación Celular/inmunología , Infecciones/inmunología , Leucocitos/citología , Accidente Cerebrovascular/inmunología , Enfermedad Aguda , Anciano , Plaquetas/inmunología , Isquemia Encefálica/inmunología , Isquemia Encefálica/patología , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Recuento de Leucocitos , Leucocitos/inmunología , Masculino , Persona de Mediana Edad , Selectina-P/metabolismo , Activación Plaquetaria/inmunología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/patología
12.
Hamostaseologie ; 26(4): 298-308, 2006 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-17146543

RESUMEN

Cerebrovascular disease is caused by ischaemic stroke, intracerebral haemorrhage, subarachnoidal haemorrhage or cerebral vein and sinus thrombosis. Approximately 80% of all cerebrovascular accidents are caused by ischaemic stroke, whereas 20% are due to primary haemorrhage. This article summarizes the typical causes of each of the four main groups of cerebrovascular disease and points out clinical differences. Special attention is given to transitory ischemic attacks since new reports underline the necessity of early diagnostic and therapeutic intervention. Useful diagnostic and clinical scales are presented and discussed.


Asunto(s)
Accidente Cerebrovascular/clasificación , Accidente Cerebrovascular/epidemiología , Isquemia Encefálica/complicaciones , Isquemia Encefálica/epidemiología , Trastornos Cerebrovasculares/epidemiología , Humanos , Incidencia , Embolia Intracraneal/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/fisiopatología
13.
Hamostaseologie ; 26(4): 309-15, 2006 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-17146544

RESUMEN

Hereditary and acquired coagulation disorders may play an important role in the pathophysiology of acute ischaemic stroke. Because of the low prevalence of these disorders and the considerable costs of unmindful diagnostic effort, a custom-tailored approach is desirable. Suggestive in favour of a possible prothrombotic clotting disorder are young patients, repeated episodes of thrombosis in the patient's history, inappropriate atherosclerotic vascular changes, previous repeated miscarriages in stroke patients, or structural cardiac abnormalities as a patent foramen ovale. Disorders affecting antithrombin III, protein C und S, APC-resistance, the prothrombin mutation, homocysteinaemia, antiphospholipid antibodies, and procoagulatory cellular interaction are discussed.


Asunto(s)
Trastornos de la Coagulación Sanguínea/fisiopatología , Accidente Cerebrovascular/epidemiología , Anticuerpos Antifosfolípidos/sangre , Trastornos de la Coagulación Sanguínea/sangre , Trastornos de la Coagulación Sanguínea/genética , Recuento de Eritrocitos , Homocisteína/sangre , Humanos , Trombosis Intracraneal/epidemiología , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Recuento de Plaquetas , Polimorfismo Genético , Proteína C/análisis , Tiempo de Protrombina
14.
Hamostaseologie ; 26(4): 316-25, 2006 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-17146545

RESUMEN

Current therapeutic concepts for acute cerebral ischaemia and cerebral haemorrhage are summarized. Patient selection for thrombolysis, the role of stroke MRI and the choice of recanalization techniques are discussed. The treatment of intracerebral haemorrhage with particular emphasis on evacuation of haematoma and acute haemostatic therapy are discussed.


Asunto(s)
Accidente Cerebrovascular/terapia , Enfermedad Aguda , Anticoagulantes/uso terapéutico , Temperatura Corporal , Ensayos Clínicos como Asunto , Humanos , Selección de Paciente , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Terapia Trombolítica
15.
J Am Coll Cardiol ; 14(3): 597-603, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2768709

RESUMEN

Because acute coronary thrombosis can cause unstable coronary artery disease, fibrinopeptide A, a reliable marker of coagulation activity, may play a role in the evaluation of unstable ischemic syndromes. A new method of fibrinopeptide A sampling, spot urine normalized to urinary creatinine, was evaluated in patients with stable and unstable angina pectoris and acute myocardial infarction. Serial samples were obtained to characterize the changes in urinary fibrinopeptide A levels over time in patients with ischemic heart disease. Admission values (mean +/- SD) were similar in the control group (3.3 +/- 1.4 ng/mg creatinine) and the stable angina group (3.2 +/- 1.1 ng/mg creatinine) (p = NS). Values in the unstable angina group (5.7 +/- 2.6 ng/mg creatinine) were higher than those in the control (p = 0.008) and stable angina (p less than 0.001) groups. Myocardial infarction admission values (8.4 +/- 10.0 ng/mg creatinine) were higher than those in the control (p = 0.005) and stable angina (p less than 0.001) groups, but not higher than those in the unstable angina group. Peak values (the highest of multiple samples) were higher in the unstable angina group (7.6 +/- 5.9 ng/mg creatinine) than in the stable angina group (4.0 +/- 1.0 ng/mg creatinine) (p = 0.04), but not in the control group (4.5 +/- 1.9 ng/mg creatinine) (p = 0.056). The two patients with unstable angina with the highest peak values subsequently exhibited infarction. Peak values in patients with infarction (44.5 +/- 60.0 ng/mg creatinine) were significantly higher than those in patients with unstable (p = 0.03) or stable (p = 0.002) angina and control patients (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Enfermedad Coronaria/orina , Fibrinógeno/orina , Fibrinopéptido A/orina , Angina de Pecho/orina , Angina Inestable/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/orina , Estudios Prospectivos
16.
J Am Coll Cardiol ; 21(3): 692-9, 1993 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-8436751

RESUMEN

OBJECTIVES: We examined the relation between the level of urinary fibrinopeptide A and the presence of angiographic intracoronary thrombus in patients with unstable angina to determine whether this marker predicts active thrombus formation. BACKGROUND: Although it is known that thrombus plays a role in acute ischemic syndromes, a noninvasive method to predict its presence in individual patients with unstable angina has not been determined. Fibrinopeptide A is a polypeptide cleaved from fibrinogen by thrombin and thus is a sensitive marker of thrombin activity and fibrin generation. METHODS: Angiographic thrombus, graded 0 to 4, and the presence of ST segment depression or T wave inversions, or both, on the electrocardiogram (ECG) were related to fibrinopeptide A levels in 24 patients with rest angina of new onset, 18 with crescendo angina, 19 with stable angina and 9 with chest pain but without coronary artery disease. All patients had chest pain within the 24 h of sample acquisition. RESULTS: The angiographic incidence of thrombus was significantly higher in patients with new onset of rest angina (67%, p < 0.001) and crescendo angina (50%, p < 0.001) as were fibrinopeptide A levels (p = 0.002). Fibrinopeptide A levels correlated significantly (p < 0.001) with the presence of a filling defect (grade 4 intracoronary thrombus) or contrast staining (grade 3). All patients with fibrinopeptide A > or = 8 ng/mg creatinine showed grade 3 to 4 thrombus and 15 of 16 patients with levels > or = 6.0 ng/mg creatinine exhibited angiographic evidence of thrombus (13 with grades 3 to 4). Patients with reversible ST changes on the ECG had significantly higher levels of fibrinopeptide A (p < 0.001), and ST changes correlated significantly with the presence of angiographic thrombus (p < 0.001). Nonetheless, a significant minority of patients with unstable angina had neither angiographic nor biochemical evidence of thrombus. CONCLUSIONS: Elevated fibrinopeptide A levels in unstable angina reflected active intracoronary thrombus formation and were present in patients with angina of new onset as well as crescendo angina. Reversible ST changes are accompanied by thrombin activity and angiographic thrombus formation. However, a sizable percentage of patients with unstable angina had no evidence of thrombus and these patients may have had transient platelet aggregation without fibrin thrombus formation.


Asunto(s)
Angina Inestable/complicaciones , Trombosis Coronaria/etiología , Fibrinopéptido A/orina , Angiografía Coronaria , Trombosis Coronaria/diagnóstico , Trombosis Coronaria/epidemiología , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Análisis de Regresión
17.
Trends Endocrinol Metab ; 3(10): 366-70, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18407123

RESUMEN

Because the infant's brain is to a large extent dependent on glucose utilization, hypoglycemia of infants can have grave effects on brain function, and it is important to diagnose it and, when possible, treat it promptly. Causes of hypoglycemia in infants are (a) excess insulin secretion, (b) factitious hyperinsulinemia, (c) GH or ACTH deficiency, (d) primary glucocorticoid deficiency, (e) defects of the enzymes involved in hepatic glucose production, or (f) defects in hepatic fatty acid oxidation.

18.
J Leukoc Biol ; 35(5): 475-87, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6425443

RESUMEN

The purpose of this study was to evaluate the effects of high and low therapeutic doses of methotrexate (MTX) on macrophage metabolism and function in vitro. Monolayers of elicited rat peritoneal macrophages (PM) were exposed to a wide range of MTX concentrations (10(-8) M-10(-3) M) for 24 or 48 hr and macrophage RNA and protein metabolism were evaluated by the incorporation of [3H]5-uridine and [14C]1-leucine, respectively, into trichloroacetic acid (TCA)-precipitable material. Macrophage functional activity was examined by measuring the uptake of [14C]Pseudomonas aeruginosa to assess phagocytosis and the release of 51Cr from antibody-coated [51Cr]sheep red blood cells (SRBC) to assess antibody-dependent cell-mediated cytotoxicity. Following a 24-hr incubation with 10(-3) M MTX, incorporation of [3H]5-uridine into PM monolayers was enhanced 79% when compared to control monolayers (p less than 0.005). Washout studies revealed that the stimulation of uridine incorporation was no longer observed by 24 hr following the removal of MTX from the culture medium. Incubation with 10(-3) M MTX for 48 hr returned uridine incorporation to control levels, although leucine incorporation into protein was reduced by 22% (p less than 0.01). The depression in leucine incorporation in the presence of 10(-3) M MTX was not reversed after the removal of MTX from the culture medium. Uptake of [14C]P. aeruginosa was not altered following a 24- or 48-hr incubation with either 10(-7) M or 10(-3) M MTX. Similarly, [51Cr]SRBC cytolysis was not affected by a 2-hr preincubation with and continuous exposure to between 10(-8) M and 10(-3) M MTX. These results demonstrate that incubation of inflammatory macrophages with clinically high doses of MTX can alter macrophage RNA and protein metabolism without producing demonstrable changes in macrophage functional activity.


Asunto(s)
Inflamación/fisiopatología , Macrófagos/fisiología , Metotrexato/toxicidad , Animales , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Resistencia a Medicamentos , Cinética , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Fagocitosis/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , Pseudomonas aeruginosa , Ratas , Ratas Endogámicas , Transcripción Genética/efectos de los fármacos
19.
J Leukoc Biol ; 52(4): 449-55, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1328445

RESUMEN

The acute phase protein, C-reactive protein (CRP), when heat-aggregated (Agg-CRP), potentiates immunoglobulin G (IgG) Fc receptor-mediated luminol-enhanced chemiluminescence (CL) in human monocytes and neutrophils. Luminol-CL is a sensitive measure of phagocyte respiratory burst activity; however, the nature of oxidative products contributing to the light emission and their site of generation remain incompletely defined. To more precisely describe the oxidative burst of monocytes and neutrophils to Agg-CRP, superoxide anion release was measured by cytochrome c reduction. In addition, the extracellular release of hydrogen peroxide was distinguished from hydrogen peroxide generation using a phenol red oxidation assay. Finally, a flow cytometric determination of dichlorofluorescein (DCFH) oxidation was employed as an index of intracellular peroxide production. Although Agg-CRP alone did not stimulate hydrogen peroxide generation by either monocytes or neutrophils, it significantly enhanced hydrogen peroxide generation in response to heat-aggregated IgG (Agg-IgG). In contrast, Agg-CRP did not enhance the extracellular release of either hydrogen peroxide or superoxide anion from Agg-IgG-stimulated cells. The capacity of Agg-CRP to enhance selectively intracellular oxidative product generation was confirmed when measuring DCFH oxidation in Agg-IgG-stimulated cells. To evaluate whether this selective enhancement of intracellular oxidative events could be attributed, at least in part, to a scavenging effect of Agg-CRP, a cell-free oxygen radical-generating system was employed. Agg-CRP did not significantly diminish the lucigenin-amplified CL response induced by the xanthine/xanthine oxidase reaction. These results indicate that although Agg-CRP enhances the intracellular generation of reactive oxygen intermediates by monocytes and neutrophils, extracellular release of those products is not influenced by cell interaction with Agg-CRP. It is tempting to speculate that CRP can selectively boost the microbicidal activities of monocytes and neutrophils within an inflammatory site by amplifying the intracellular generation of reactive oxygen products without increasing damage to surrounding normal tissues.


Asunto(s)
Proteína C-Reactiva/farmacología , Inmunoglobulina G/farmacología , Monocitos/metabolismo , Neutrófilos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Acridinas/metabolismo , Adulto , Proteína C-Reactiva/fisiología , Células Cultivadas , Grupo Citocromo c/metabolismo , Sinergismo Farmacológico , Fluoresceínas/metabolismo , Calor , Humanos , Peróxido de Hidrógeno/metabolismo , Líquido Intracelular/metabolismo , Mediciones Luminiscentes , Monocitos/citología , Monocitos/efectos de los fármacos , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Oxidación-Reducción , Fagocitos/metabolismo , Fenolsulfonftaleína/metabolismo , Estallido Respiratorio/efectos de los fármacos , Estallido Respiratorio/fisiología , Estimulación Química , Superóxidos/metabolismo , Xantina , Xantina Oxidasa/metabolismo , Xantinas/metabolismo
20.
J Leukoc Biol ; 40(6): 769-83, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3465838

RESUMEN

We had previously demonstrated that C-reactive protein (CRP), an acute phase reactant, when aggregated or coupled to a ligand, interacts with monocytes and certain human peripheral blood lymphocytes. The purpose of the present study, after further characterizing the binding interaction of CRP with human monocytes, was to focus on the biological response of monocytes to CRP binding. Flow cytometric analysis of human mononuclear leukocytes, following incubation with fluoresceinated heat-aggregated CRP (Agg-CRP), revealed that while greater than 70% of monocytes bound Agg-CRP, only 8% of lymphocytes demonstrated positive fluorescence. Furthermore, mean channel fluorescence values indicated that monocytes bound greater amounts of Agg-CRP per cell than did lymphocytes. Luminol-enhanced chemiluminescence (CL) was used as a measure of monocyte respiratory burst activity. Monocytes were stimulated only minimally by Agg-CRP alone; however, Agg-CRP substantially enhanced the CL response to heat-aggregated IgG. This Agg-CRP enhancing effect was selective for IgG-initiated monocyte activation, as no augmentation in CL was observed following cell stimulation with phorbol myristate acetate or serum-opsonized zymosan. These results demonstrate that aggregated CRP binds to the major proportion of human monocytes and selectively augments Fc receptor-mediated stimulation of monocyte oxidative metabolism.


Asunto(s)
Proteína C-Reactiva/fisiología , Monocitos/fisiología , Citometría de Flujo , Calor , Humanos , Inmunoglobulina G/metabolismo , Mediciones Luminiscentes , Linfocitos/metabolismo , Consumo de Oxígeno , Unión Proteica , Relación Estructura-Actividad , Acetato de Tetradecanoilforbol/farmacología , Zimosan
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