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OBJECTIVES: To determine the long-term outcomes among a cohort of patients with Kawasaki disease (KD) and a history of giant coronary artery aneurysms (CAAs) at a single US center. STUDY DESIGN: Medical records for all patients with KD and giant CAAs at a pediatric academic institution were reviewed. Primary outcomes included major adverse cardiovascular events (MACE) and normalization of CA luminal diameter, using Kaplan-Meier analyses. RESULTS: There were 60 patients with KD and giant CAAs identified between 1989 and 2023. The majority of patients were male (71.7%) with a median age at diagnosis of 0.9 years (range, 0.2-13.3 years). Patients were followed for a median of 11 years, up to 34.5 years. MACE occurred in 13 patients (21.7%) at a median of 1.4 years (range, 0.04-22.6 years) after KD diagnosis. The 10-, 20-, and 30-year MACE-free rates were 75%, 75%, and 60%. Patients with maximal CA z scores of ≥20 or bilateral CAA were more likely to have MACE. During follow-up, 26.7% of CAA regressed to a normal luminal diameter at a median of 3.6 years (range, 0.6-12.0 years). The 10-, 20- and 30-year likelihood of CA regression to normal luminal diameter was 36%, 46%, and 46%. CONCLUSIONS: Over 30 years, MACE occurred in nearly 22% of patients, more often in those with bilateral CAA or CA z scores of ≥20. Despite regression to a normal luminal diameter in >25% of CAAs, patients with a history of KD-associated giant CAA require ongoing surveillance for cardiac complications, even years after the initial disease.
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In children with hypertrophic cardiomyopathy (HCM), the genotype-phenotype association of abnormal electrocardiographic (ECG) features in the backdrop of gene positivity has not been well described. This study aimed to describe the abnormal ECG findings in children with HCM harboring who have genetic variants and determine the association with major adverse cardiac events (MACE). We retrospectively analyzed 81 variants-positive, phenotype-positive (V+P+), 66 variant-positive, phenotype-negative (V+P-), and 85 non-sarcomeric subjects. We analyzed ECG findings and clinical outcomes in the three groups of subjects. Repolarization abnormalities (ST and T wave changes) and pathologic Q waves were the most common abnormalities in variant and non-sarcomeric subjects. The V+P+ group showed higher occurrence of ST segment changes and T wave abnormalities compared to V+P- group. Independent predictors of MACE included ST segment changes (OR 3.54, CI 1.20-10.47, p = 0.022). T wave changes alone did not predict outcome (OR 2.13, CI 0.75-6.07, p = 0.157), but combined repolarization abnormalities (ST+T changes) were strong predictors of MACE (OR 5.84, CI 1.43-23.7, p = 0.014) than ST segment changes alone. Maximal wall z score by echocardiography was a predictor of MACE (OR 1.21, CI 1.07-1.37, p = 0.002). Despite the presence of significant myocardial hypertrophy (z score > 4.7), voltage criteria for LVH were much less predictive. In the non-sarcomeric group, RVH was significantly associated with MACE (OR 3.85, CI 1.08-13.73, p = 0.038). These abnormal ECG findings described on the platform of known genetic status and known myocardial hypertrophy may add incremental value to the diagnosis and surveillance of disease progression in children with HCM. Select ECG findings, particularly repolarization abnormalities, may serve as predictors of MACE in children.
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Monoclonal antibodies are the leading class of biopharmaceuticals in terms of numbers approved for therapeutic purposes. Antigen-binding fragments (Fab) are also used as biotherapeutics and used widely in research applications. The dominant expression systems for full-length antibodies are mammalian cell-based, whereas for Fab molecules the preference has been an expression in bacterial systems. However, advances in CHO and downstream technologies make mammalian systems an equally viable option for small- and large-scale Fab production. Using a panel of full-length IgG antibodies and their corresponding Fab pair with different antigen specificities, we investigated the impact of the IgG and Fab molecule format on production from Chinese hamster ovary (CHO) cells and assessed the cellular capability to process and produce these formats. The full-length antibody format resulted in the recovery of fewer mini-pools posttransfection when compared to the corresponding Fab fragment format that could be interpreted as indicative of a greater overall burden on cells. Antibody-producing cell pools that did recover were subsequently able to achieve higher volumetric protein yields (mg/L) and specific productivity than the corresponding Fab pools. Importantly, when the actual molecules produced per cell of a given format was considered (as opposed to mass), CHO cells produced a greater number of Fab molecules per cell than obtained with the corresponding IgG, suggesting that cells were more efficient at making the smaller Fab molecule. Analysis of cell pools showed that gene copy number was not correlated to the subsequent protein production. The amount of mRNA correlated with secreted Fab production but not IgG, whereby posttranscriptional processes act to limit antibody production. In summary, we provide the first comparative description of how full-length IgG and Fab antibody formats impact on the outcomes of a cell line construction process and identify potential limitations in their production that could be targeted for engineering increases in the efficiency in the manufacture of these recombinant antibody formats.
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Fragmentos Fab de Inmunoglobulinas , Inmunoglobulina G , Proteínas Recombinantes , Animales , Células CHO , Técnicas de Cultivo de Célula , Cromatografía Líquida de Alta Presión , Cricetinae , Cricetulus , Fragmentos Fab de Inmunoglobulinas/análisis , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/aislamiento & purificación , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/análisis , Inmunoglobulina G/química , Inmunoglobulina G/aislamiento & purificación , Inmunoglobulina G/metabolismo , Proteínas Recombinantes/análisis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismoRESUMEN
Although elevated right ventricular pressure and left ventricular diastolic dysfunction measured by echocardiogram are independent predictors of death in adults with sickle cell disease (SCD), the utility of routine echocardiographic screening in the pediatric population is controversial. We performed a 3-year retrospective review of children ≥ 10 years of age with SCD who underwent an outpatient transthoracic echocardiogram as part of a screening program. Of 172 patients referred for screening, 105 (61%) had a measurable tricuspid regurgitation jet velocity (TRV): median 2.4 m/s (IQR 2.3-2.5). Elevated right ventricular (RV) pressure (TRV ≥ 2.5 m/s, 25 mmHg), documented in 30% (32/105), was significantly associated with chronic transfusion therapy and elevated lactate dehydrogenase. Left ventricle (LV) dilation, documented in 25% (44/172), was significantly associated with lower hemoglobin, and higher reticulocyte count, lactate dehydrogenase level, and bilirubin level. There was no association between elevated right ventricular pressure or left ventricle dilation and indices of biventricular systolic or diastolic function. The one death in the cohort during the study period had normal echocardiographic findings. In conclusion, mild RV pressure elevation and LV dilation in children with SCD is associated with abnormal laboratory markers of disease severity, but not with ventricular dysfunction over the 3-year study period.
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Anemia de Células Falciformes/fisiopatología , Función Ventricular Izquierda/fisiología , Función Ventricular Derecha/fisiología , Adolescente , Anemia de Células Falciformes/complicaciones , Niño , Progresión de la Enfermedad , Ecocardiografía , Femenino , Humanos , Masculino , Estudios Retrospectivos , Medición de RiesgoRESUMEN
Rodent monoclonal antibodies with specificity towards important biological targets are developed for therapeutic use by a process of humanisation. This process involves the creation of molecules, which retain the specificity of the rodent antibody but contain predominantly human coding sequence. Here, we show that some humanised heavy chains (HCs) can fold, form dimers and be secreted even in the absence of a light chain (LC). Quality control of recombinant antibody assembly in vivo is thought to rely upon folding of the HC CH1 domain. This domain acts as a switch for secretion, only folding upon interaction with the LC CL domain. We show that the secreted heavy-chain dimers contain folded CH1 domains and contribute to the heterogeneity of antibody species secreted during the expression of therapeutic antibodies. This subversion of the normal quality control process is dependent on the HC variable domain, is prevalent with engineered antibodies and can occur when only the Fab fragments are expressed. This discovery will have an impact on the efficient production of both humanised antibodies and the design of novel antibody formats.
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Anticuerpos Monoclonales/biosíntesis , Inmunoglobulina G/metabolismo , Cadenas Pesadas de Inmunoglobulina/metabolismo , Cadenas Ligeras de Inmunoglobulina/metabolismo , Proteínas Recombinantes/metabolismo , Secuencia de Aminoácidos , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Células CHO , Cricetulus , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/química , Cadenas Pesadas de Inmunoglobulina/química , Cadenas Ligeras de Inmunoglobulina/química , Pliegue de Proteína , Proteínas Recombinantes/químicaRESUMEN
Total anomalous pulmonary venous connection (TAPVC) is a rare form of congenital heart disease in which the pulmonary veins drain by various pathways to the right atrium instead of the left atrium. Postoperative obstruction of the pulmonary veins is a known complication. Identifying risk factors for morbidity and mortality is important for counseling and monitoring. We describe a pattern of postoperative obstruction in a specific arrangement of mixed TAPVC. Five patients with a type of mixed TAPVC, namely, three pulmonary veins connecting to the coronary sinus and the left upper pulmonary vein (LUPV) connecting to the innominate vein, were identified over an 11-year period at our institution. Two additional patients with this TAPVC arrangement were cared for at our institution after having surgery at other institutions. Of these, one patient received only comfort care at birth due to other clinical issues. The six other patients underwent surgical unroofing of the coronary sinus. The anomalous LUPV was not addressed during the initial surgery in any of these cases. Following repair, one patient died from non-cardiac reasons. The remaining five patients all developed obstruction of the repaired pulmonary veins with decompression through the unrepaired LUPV, requiring surgical revision. Three patients underwent a second reoperation as well. Three of the six repaired patients also developed refractory atrial arrhythmias. This cohort suggests that this mixed TAPVC pattern predisposes patients to obstruction after surgical repair. Further investigation may aid pediatric cardiologists in risk-stratifying and counseling these patients. Alternative surgical approaches may need to be considered.
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Procedimientos Quirúrgicos Cardíacos/efectos adversos , Complicaciones Posoperatorias/etiología , Venas Pulmonares/cirugía , Síndrome de Cimitarra/cirugía , Angiografía/métodos , Niño , Humanos , Lactante , Recién Nacido , Masculino , Venas Pulmonares/patología , Reoperación/estadística & datos numéricos , Estudios RetrospectivosRESUMEN
OBJECTIVE: To evaluate the impact of a pediatric emergency department (ED) chest pain clinical pathway on resource utilization. METHODS: Motivated by perceived overuse of cardiology consultation for non-cardiac chest pain in the ED, clinicians from the Divisions of Cardiology and Emergency Medicine collaboratively developed a chest pain clinical pathway, educated staff, and implemented the pathway on March 1, 2014. We reviewed records of children aged 3 to 18 years without prior diagnoses of heart disease who presented to the ED with chest pain between March 1, 2013, and April 22, 2015. We compared diagnostic testing rates, ED length of stay, and cardiology consults before and after implementation of the pathway. RESULTS: A total of 1687 patients were pathway eligible (675 patients preimplementation and 1012 postimplementation). Resource utilization was lower than expected before pathway implementation and remained low after implementation. There was a statistically significant reduction in rates of chest x-ray ordering after pathway implementation and ED length of stay but no change in other diagnostic testing or cardiology consultation. Follow-up in our health care system for pediatric chest pain increased from 15% to 29% with implementation, but none of these visits resulted in the diagnosis of a new cardiac condition. There were no instances identified where use of the pathway resulted in missed cardiac disease. CONCLUSIONS: Implementation of a clinical pathway for pediatric chest pain did lead to a reduction in chest x-ray ordering in the ED and was associated with a higher rate of outpatient follow up for non-pathologic chest pain. Preimplementation utilization was lower than the prepathway perceptions of overuse suggested.
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Dolor en el Pecho/diagnóstico , Vías Clínicas/estadística & datos numéricos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Niño , Preescolar , Femenino , Recursos en Salud/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Ensayos Clínicos Controlados no Aleatorios como Asunto , Derivación y Consulta/estadística & datos numéricosRESUMEN
Paediatric exercise stress testing has historically been used to assess the functional status of patients after repair of CHDs and to assess the efficacy of medical or device therapy in patients with arrhythmias. Exercise stress testing is one of very few hospital- or clinic-based tests that can assess the response of the cardiopulmonary system in an environment that simulates the body's response to vigorous play and competitive sport. Exercise stress testing is therefore a useful modality in the assessment of child and athletes at risk for sudden cardiac death. The author discusses some cardiovascular maladies that can cause sudden cardiac death by utilising case illustrations as a learning tool.
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Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Muerte Súbita Cardíaca/etiología , Prueba de Esfuerzo , Ejercicio Físico/fisiología , Adolescente , Atletas , Niño , Ecocardiografía , Electrocardiografía , Humanos , DeportesRESUMEN
BACKGROUND: Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients. Methods and results This study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman's Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6-33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (-0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (-0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63-0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)]. CONCLUSIONS: Higher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.
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Biomarcadores/sangre , Gasto Cardíaco/fisiología , Procedimiento de Fontan/métodos , Cardiopatías Congénitas/sangre , Monitoreo Fisiológico/métodos , Adolescente , Adulto , Niño , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/fisiopatología , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Curva ROC , Adulto JovenRESUMEN
OBJECTIVE: To retrospectively report the historical and clinical findings, diagnostics, treatment, and outcome of horses with penetrating wood foreign bodies (PWFBs) of the coronary band. ANIMALS: 15 client-owned horses. CLINICAL PRESENTATION: Horses had varying degrees of lameness and soft tissue swelling of the coronary band and pastern region. A defect in the coronary band was identified, but the actual wood foreign body was not always readily visualized. RESULTS: Medical records of horses diagnosed with PWFBs of the coronary band between 2004 and 2023 were reviewed. Information retrieved from the medical records included history, signalment, diagnostics, treatment, and outcome. Thirteen of 15 horses that sustained a PWFB to the coronary band were participating in foxhunting. Penetrating wood foreign bodies occurred more frequently near the central axis or toe region (11/15) and more commonly in the forelimbs (11/15). Removal of PWFBs can be performed with the horse standing and sedated with regional anesthesia. Complete removal of the PWFB required partial removal of the adjacent hoof wall. CLINICAL RELEVANCE: Penetrating wood foreign bodies occurred in the coronary band and lodged distally in the hoof wall of horses. Foxhunting may be a risk factor for this type of injury. Penetrating wood foreign bodies occurred most commonly in the front feet, near the central axis of the coronary band. Complete removal of the PWFB required removing a section of the adjacent hoof wall. The prognosis for return to the previous level of activity following treatment was favorable.
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Cuerpos Extraños , Madera , Animales , Caballos , Cuerpos Extraños/veterinaria , Cuerpos Extraños/cirugía , Masculino , Estudios Retrospectivos , Femenino , Pezuñas y Garras/patología , Enfermedades de los Caballos/cirugíaRESUMEN
The integrity of antibody structure, stability, and biophysical characterization are becoming increasingly important as antibodies receive increasing scrutiny from regulatory authorities. We altered the disulfide bond arrangement of an IgG4 molecule by mutation of the Cys at the N terminus of the heavy chain constant domain 1 (C(H)1) (Kabat position 127) to a Ser and introduction of a Cys at a variety of positions (positions 227-230) at the C terminus of C(H)1. An inter-LC-C(H)1 disulfide bond is thus formed, which mimics the disulfide bond arrangement found in an IgG1 molecule. The antibody species present in the supernatant following transient expression in Chinese hamster ovary cells were analyzed by immunoblot to investigate product homogeneity, and purified product was analyzed by a thermofluor assay to determine thermal stability. We show that the light chain can form an inter-LC-C(H)1 disulfide bond with a Cys when present at several positions on the upper hinge (positions 227-230) and that such engineered disulfide bonds can consequently increase the Fab domain thermal stability between 3 and 6.8 °C. The IgG4 disulfide mutants displaying the greatest increase in Fab thermal stability were also the most homogeneous in terms of disulfide bond arrangement and antibody species present. Importantly, mutations did not affect the affinity for antigen of the resultant molecules. In combination with the previously described S241P mutation, we present an IgG4 molecule with increased Fab thermal stability and reduced product heterogeneity that potentially offers advantages for the production of IgG4 molecules.
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Fragmentos Fab de Inmunoglobulinas/química , Inmunoglobulina G/química , Inmunoglobulina G/metabolismo , Secuencia de Aminoácidos , Animales , Western Blotting , Células CHO , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Cricetinae , Disulfuros , Humanos , Fragmentos Fab de Inmunoglobulinas/genética , Inmunoglobulina G/genética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Ingeniería de Proteínas , Estabilidad Proteica , Homología de Secuencia de AminoácidoRESUMEN
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a familial form of cardiomyopathy typically caused by mutations in genes that encode an element of the cardiac desmosome. Branchio-oculo-facial syndrome (BOFS) is a craniofacial disorder caused by TFAP2A mutations. In a family segregating ARVD/C, some members also had features of BOFS. Genetic testing for ARVD/C identified a mutation in PKP2, encoding plakophilin-2, a component of the cardiac desmosome. Evaluation of dysmorphology by chromosome microarray (CMA) identified a 4.4 Mb deletion at chromosome 6p24 that included both TFAP2A and DSP, encoding desmoplakin, an additional component of the cardiac desmosome implicated in ARVD/C. A family member with both the 6p24 deletion and PKP2 mutation had more severe cardiac dysfunction. These findings suggest that this contiguous gene deletion contributes to both ARVD/C and BOFS, and that DSP haploinsufficiency may contribute to cardiomyopathy. This family provides a clinical example that underscores the need for careful evaluation in clinical scenarios where genetic heterogeneity is known to exist. Finally, it suggests that individuals with unexplained cardiomyopathy and dysmorphic facial features may benefit from CMA analysis.
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Displasia Ventricular Derecha Arritmogénica/diagnóstico por imagen , Síndrome Branquio Oto Renal/diagnóstico por imagen , Adulto , Displasia Ventricular Derecha Arritmogénica/genética , Displasia Ventricular Derecha Arritmogénica/fisiopatología , Síndrome Branquio Oto Renal/genética , Síndrome Branquio Oto Renal/fisiopatología , Deleción Cromosómica , Cromosomas Humanos Par 6 , Femenino , Estudios de Asociación Genética , Humanos , Técnicas de Diagnóstico Molecular , Linaje , Fenotipo , Volumen Sistólico , UltrasonografíaRESUMEN
OBJECTIVES: To assess the usefulness of histopathologic examination in forensic autopsies. MATERIAL AND METHODS: All consecutive pathological reports and slides from forensic autopsies performed in our department since 2006 have been reviewed. RESULTS: Four hundred forensic necropsies were reviewed. In only 150 cases (38%), pathologists had data about manner of death and gross autopsy findings. Major diagnoses, related to death, and unsuspected by forensic pathologists, were discovered in 83 cases (21%): in 48 cases (12%) gross examination of the heart, lungs and liver showed gross diagnoses missed by the forensic pathologists, and in only 35 cases (9%) microscopic examination revealed a major unsuspected diagnosis (in brain, heart, lungs, liver, kidney and pancreas specimens). In 213 cases (53%), histopathologic examination confirmed gross autopsy findings and allowed to date some wounds. In 104 cases (26%), microscopic examination was not contributory. CONCLUSION: Microscopic examination revealed major diagnoses in less than 10% of forensic autopsies. Its effectiveness is limited for homicides and suicides. Systematic microscopic examination of numerous organs is often useless and should be limited to cases with no anatomic causes of death. Our study emphasizes the need for a better communication between forensic pathologists and histopathologists, and for a better training of some forensic pathologists for gross examination.
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Autopsia/normas , Patologia Forense/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Niño , Preescolar , Femenino , Francia , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Background: Exercise stress testing (EST) in pediatric hypertrophic cardiomyopathy (HCM) patients has not well described in a large heterogenous cohort. Objectives: The objective of the study was to determine the clinical utility of EST in pediatric HCM. Methods: This was a retrospective single-center analysis of HCM patients younger than 21 years who had EST between January 1, 2000, and January 1, 2019. Clinical, demographic characteristics, and EST data were analyzed, using the last EST during the study or prior to the event in subjects with a primary outcome. The primary composite endpoint included cardiac death, transplant, or arrhythmia requiring implantable cardioverter-defibrillator placement. Outcome analysis was performed using Cox proportional hazard modeling. Results: The study cohort included 140 patients, 52% with a recognized genetic variant. There were 2 tests aborted due to safety concerns (ST-segment changes, ventricular ectopy). The median age at first EST was 13.6 years. Ninety percent of patients were tested using cycle ergometry, and 44% were on a beta-blocker. The median peak oxygen consumption was 37.1 mL/kg/min (IQR: 12.5 mL/kg/min) or 81.2% predicted, the mean anaerobic threshold was 21.8 Ml (IQR: 8.3 mL), and the median peak power was 2.6 ± 1.1 W/kg or 73.7% predicted. Ectopy during EST was seen in 44% of patients, and 8% had an abnormal blood pressure response to exercise. The endpoint was reached in 12 patients. The presence of any degree of ectopy was a predictor of the composite endpoint (hazard ratio: 5.8; 95% CI: 1.3-26.7). Conclusions: EST is clinically useful in select pediatric patients with HCM. Ectopy on EST is a risk factor for cardiac death, cardiac transplant, and arrhythmias requiring implantable cardioverter-defibrillator.
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Monoclonal antibodies have recently started to deliver on their promise as highly specific and active drugs; however, a more effective, knowledge-based approach to the selection, design, and optimization of potential therapeutic antibodies is currently limited by the surprising lack of detailed structural information for complexes formed with target proteins. Here we show that complexes formed with minimal antigen binding single chain variable fragments (scFv) reliably reflect all the features of the binding interface present in larger Fab fragments, which are commonly used as therapeutics, and report the development of a robust, reliable, and relatively rapid approach to the determination of high resolution models for scFv-target protein complexes. This NMR spectroscopy-based approach combines experimental determination of the interaction surfaces and relative orientations of the scFv and target protein, with NMR restraint-driven, semiflexible docking of the proteins to produce a reliable and highly informative model of the complex. Experience with scFvs and Fabs targeted at a number of secreted regulatory proteins suggests that the approach will be applicable to many therapeutic antibodies targeted at proteins, and its application is illustrated for a potential therapeutic antibody targeted at the cytokine IL-1beta. The detailed structural information that can be obtained by this approach has the potential to have a major impact on the rational design and development of an increasingly important class of biological pharmaceuticals.
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Anticuerpos Monoclonales/química , Mapeo Epitopo , Fragmentos de Inmunoglobulinas/química , Región Variable de Inmunoglobulina/química , Interleucina-1beta/química , Espectroscopía de Resonancia Magnética , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/metabolismo , Diseño de Fármacos , Humanos , Fragmentos de Inmunoglobulinas/genética , Fragmentos de Inmunoglobulinas/metabolismo , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Modelos Moleculares , Conformación Proteica , Pliegue de ProteínaRESUMEN
We evaluated the presentation, treatment, and outcome of infants who present with ventricular tachycardia in the first year of life. Seventy-six infants were admitted to our institution with a diagnosis of ventricular tachycardia between January, 1987 and May, 2006. Forty-five infants were excluded from the study because of additional confounding diagnoses including accelerated idioventricular rhythm, Wolff-Parkinson-White syndrome, supraventricular tachycardia with aberrancy, long QT syndrome, cardiac rhabdomyoma, myocarditis, congenital lesions, or incomplete data. The remaining 31 included infants who had a median age at presentation of 1 day, with a range from 1 to 255 days, and a mean ventricular tachycardia rate of 213 beats per minute, with a range from 171 to 280, at presentation. The infants were treated chronically with propranolol (38.7%), amiodarone (12.9%), mexiletine (3.2%), propranolol and mexiletine (9.7%), or propranolol and procainamide (6.5%). The median duration of treatment was 13 months, with a range from 3 to 105 months. Ventricular tachycardia resolved spontaneously in all infants. No patient died, or received catheter ablation or device therapy. Median age at last ventricular tachycardia was 59 days, with a range from 1 to 836 days. Mean follow-up was 45 months, with a range from 5 to 164 months, with a mean ventricular tachycardia-free period of 40 months. Infants with asymptomatic ventricular tachycardia, a structurally normal heart, and no additional electrophysiological diagnosis all had spontaneous resolution of tachycardia. Furthermore, log-rank analysis of the time to ventricular tachycardia resolution showed no difference between children who received chronic outpatient anti-arrhythmic treatment and those who had no such therapy. While indications for therapy cannot be determined from this study, lack of symptoms or myocardial dysfunction suggests that therapy may not be necessary.
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Antiarrítmicos/uso terapéutico , Taquicardia Ventricular/tratamiento farmacológico , Ecocardiografía , Electrocardiografía , Electrocardiografía Ambulatoria , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Remisión Espontánea , Análisis de Supervivencia , Taquicardia Ventricular/fisiopatologíaRESUMEN
The aim of this study was to offer guidelines for counsellors who work with rehabilitation groups of patients with chronic pain. The sample involved nine counsellors engaged in a multidisciplinary pain management programme. Two focus group interviews were conducted. Data were analysed using qualitative content analysis. These indicate that main challenges facing counsellors were related to maintaining constructive group processes and being mentally prepared. The counsellors reported that knowledge concerning self-awareness, theoretical frameworks and counselling techniques was important. Personal learning included: group leadership, teamwork, grasping the inside story and obtaining supervision. The results show how important it is to have trained counsellors that are well prepared to prevent and deal with challenging group processes. Counsellors need to understand the concept of pain and be acquainted with cognitive behavioural framework and group processes. The results indicate that counsellors perceive regular supervision as supportive and is likely to promote good team functioning.
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Dolor/rehabilitación , Grupos de Autoayuda , Enfermedad Crónica , HumanosRESUMEN
SCC4 human keratinocytes are derived from a squamous cell carcinoma of the tongue and undergo very little spontaneous differentiation. Introduction of a wild-type beta 1 integrin subunit into SCC4 cells stimulates differentiation, suggesting either that the cells have a defect in the integrin signaling pathways that control differentiation or that the beta1 subunit itself is defective. Here we describe a heterozygous mutation in the SCC4 beta 1 subunit. The mutation, T188I, maps to the I-like domain. It results in constitutive activation of ligand binding, irrespective of the partner alpha subunit, in solid phase assays with recombinant protein and in living cells. The mutation promotes cell spreading, but not proliferation, motility, or invasiveness. It results in sustained activation of Erk MAPK independent of cell spreading. When introduced into SCC4 keratinocytes, the wild-type beta1 integrin stimulates differentiation, whereas the mutant is inactive. Activation of beta 1 integrins in normal keratinocytes also suppresses differentiation. These results establish, for the first time, mutation as a mechanism by which integrins can contribute to neoplasia, because the degree of differentiation in epithelial cancers is inversely correlated with prognosis. They also provide new insights into how integrins regulate keratinocyte differentiation.
Asunto(s)
Adhesión Celular/fisiología , Diferenciación Celular/fisiología , Integrina beta1/genética , Queratinocitos/fisiología , Mutación Puntual , Secuencia de Aminoácidos , Animales , Carcinoma de Células Escamosas , Movimiento Celular/fisiología , Embrión de Pollo , Humanos , Integrina beta1/metabolismo , Queratinocitos/citología , Ligandos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Estructura Terciaria de Proteína , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Transducción de Señal/fisiología , Células Tumorales CultivadasRESUMEN
BACKGROUND: Pulmonary venous obstruction after repair of total anomalous pulmonary venous connection (TAPVC) results in substantial morbidity and mortality. Risk factors for postoperative obstruction remain ambiguous. In addition, the existing literature has no standard definition for preoperative obstruction, making patient counseling difficult. METHODS: All patients undergoing repair of TAPVC at our institution from January 1, 2006, to October 23, 2017, were identified. The primary outcome was the development of postoperative obstruction, analyzed as a time-to-event outcome. Clinical information was extracted to assess risk factors. Degrees of preoperative obstruction were defined based on echocardiographic, catheterization, and clinical findings. Univariable and multivariable Cox proportional hazard regression methods were used to identify factors associated with the primary outcome. RESULTS: During the study interval, 119 patients underwent repair of TAPVC (40% single ventricle), and postoperative obstruction developed in 25 patients (21%). Risk factors associated with obstruction were heterotaxy syndrome, single-ventricle heart disease, additional procedures at the time of vein repair, mixed-type TAPVC, and preoperative obstruction. Having even mild preoperative obstruction (≥1.2 m/s by Doppler echocardiography) was predictive of postoperative obstruction. A multivariable model showed mixed-type TAPVC and the presence of preoperative obstruction were associated with a more than twofold greater hazard of obstruction. CONCLUSIONS: TAPVC in the setting of heterotaxy and a single ventricle remains challenging, with high rates of postoperative obstruction. Mixed-type TAPVC is an independent risk factor for postoperative obstruction, particularly in patients with isolated TAPVC. Even mild preoperative obstruction is a risk factor for postoperative obstruction. These results may help risk-stratify TAPVC patients.
Asunto(s)
Procedimientos Quirúrgicos Cardiovasculares/efectos adversos , Complicaciones Posoperatorias/etiología , Síndrome de Cimitarra/cirugía , Estenosis de Vena Pulmonar/etiología , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Atrios Cardíacos/cirugía , Humanos , Lactante , Recién Nacido , Masculino , Venas Pulmonares/anomalías , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/patología , Venas Pulmonares/cirugía , Estudios Retrospectivos , Factores de Riesgo , Síndrome de Cimitarra/diagnóstico por imagen , Grado de Desobstrucción VascularRESUMEN
BACKGROUND: Inhibitors of tumor necrosis factor alpha (TNFalpha) have demonstrated significant efficacy in chronic inflammatory diseases, including Crohn's disease (CD). To further elucidate the mechanisms of action of these agents, we compared the anti-TNFalpha agents certolizumab pegol, infliximab, adalimumab, and etanercept in several in vitro systems. METHODS: The ability of each anti-TNFalpha agent to neutralize soluble and membrane-bound TNFalpha; mediate cytotoxicity, affect apoptosis of activated human peripheral blood lymphocytes and monocytes; induce degranulation of human peripheral blood granulocytes, and modulate lipopolysaccharide (LPS)-induced interleukin (IL)-1beta production by human monocytes was measured in vitro. RESULTS: All 4 agents neutralized soluble TNFalpha and bound to and neutralized membrane TNFalpha. Infliximab and adalimumab were comparable in their ability to mediate complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity, and to increase the proportion of cells undergoing apoptosis and the level of granulocyte degranulation. Etanercept generally mediated these effects to a lesser degree, while certolizumab pegol gave similar results to the control reagents. LPS-induced IL-1beta production was inhibited by certolizumab pegol, infliximab, and adalimumab, but only partially inhibited by etanercept. CONCLUSIONS: In contrast to the other anti-TNFalpha agents tested, certolizumab pegol did not mediate increased levels of apoptosis in any of the in vitro assays used, suggesting that these mechanisms are not essential for the efficacy of anti-TNFalpha agents in CD. As certolizumab pegol, infliximab, and adalimumab, but not etanercept, almost completely inhibited LPS-induced IL-1beta release from monocytes, inhibition of cytokine production may be important for efficacy of anti-TNFalpha agents in CD.