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1.
Exp Clin Endocrinol Diabetes ; 120(9): 507-10, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23070828

RESUMEN

OBJECTIVE: We aimed at evaluating BMI changes during GH therapy pause, to assess the transfer pattern between children and adult medical services in our clinic and to confirm the previous growth hormone deficiency (GHD) diagnosis. DESIGN: Retrospective cohort study. METHODS: We identified 75 transition patients (age at first visit <25 years) with pituitary deficiency (ICD-10:E.23) and GHD referred to our clinic between 2000-2009. RESULTS: Out of 75 patients with GHD (45 males, 30 females), 20 subjects suffered from an idiopathic GHD (iGHD) and 55 from an organic GHD (oGHD). During the GH therapy pause (26.4±34.8 months), we observed a significant BMI increase (23.6±4.4 to 27.1±7.2, p=0.02). Most males with iGHD discontinued endocrinologic control and GH substitution completely (5 patients out of 20) or after the first contact (3 patients out of 20). Most females with GHD continued medical control after transferral (22 patients). We retested 34/75 patients with GHD (45.3%). The preferred test was the growth hormone-releasing hormone-arginine (GHRH-arginine) (20/34 patients, 58.9%), followed by the insulin hypoglycemia test (IHT) alone (9 patients). 4 patients received both, the GHRH-arginine and the IHT. Seven retested patients with iGHD (63.6%) and all oGHD retested patients were still deficient. CONCLUSIONS: Our results provide information on negative effects of the discontinuation of GH treatment during the transition phase and should help to improve the compliance with treatment in this group of patients. Paediatric and adult endocrinologists participating together in a transition programme should emphasize on the positive effect of GH substitution in adulthood. Efforts should be made to particularly improve the transferral of male adolescents with iGHD, since they seem to escape medical care.


Asunto(s)
Desarrollo del Adolescente , Terapia de Reemplazo de Hormonas , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/uso terapéutico , Transición a la Atención de Adultos , Aumento de Peso , Adolescente , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Monitoreo de Drogas , Femenino , Alemania , Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Cumplimiento de la Medicación , Servicio Ambulatorio en Hospital , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Adulto Joven
2.
Hamostaseologie ; 32 Suppl 1: S29-38, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22961422

RESUMEN

A longer acting recombinant FVIII is expected to serve patients' demand for a more convenient prophylactic therapy. We have developed BAX 855, a PEGylated form of Baxter's rFVIII product ADVATE™ based on the ADVATE™ manufacturing process. The conjugation process for preparing BAX 855 uses a novel PEG reagent. The production process was adjusted to yield a rFVIII conjugate with a low PEGylation degree of about 2 moles PEG per FVIII molecule. This optimised modification degree resulted in an improved PK profile for rFVIII without compromising its specific activity. PEGylation sites were identified by employing various HPLC- and MS-based methods. These studies not only indicated that about 60% of the PEG chains are localised to the B-domain, which is cleaved off upon physiological activation during the coagulation process, but also demonstrated an excellent lot to lot consistency with regard to PEGylation site distribution. Detailed biochemical characterization further showed that PEGylated FVIII retained all the physiological functions of the FVIII molecule with the exception of binding to the LRP clearance receptor which was reduced for BAX 855 compared to ADVATE™. This might provide an explanation for the prolonged circulation time of BAX 855 as reduced receptor binding might slow-down clearance. Preclinical studies showed improved pharmacokinetic behaviour and clinically relevant prolonged efficacy compared to ADVATE™ without any signs of toxicity or elevated immunogenicity. The comprehensive preclinical data package formed the basis for approval of the phase 1 clinical study by European authorities which started in 2011.


Asunto(s)
Diseño de Fármacos , Factor VIII/administración & dosificación , Factor VIII/química , Hemofilia A/tratamiento farmacológico , Liposomas/química , Polietilenglicoles/química , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Factor VIII/farmacocinética , Semivida , Hemofilia A/metabolismo , Humanos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
3.
Horm Res Paediatr ; 75(4): 264-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21196707

RESUMEN

CONTEXT: Mild forms of simple virilizing congenital adrenal hyperplasia (CAH) may be missed in newborn screening. In the pre-newborn-screening era, missed diagnosis of simple virilizing CAH was not infrequent in boys. Elevated adrenal androgens lead to accelerated growth and bone maturation. Traditional treatment of CAH consists of the suppression of ACTH through glucocorticoid replacement, in an attempt to reduce excessive androgen production. OBJECTIVE: To retrospectively analyze early growth pattern and bone maturation in untreated boys with simple virilizing CAH. PATIENTS: In the pre-newborn screening era, 13 boys had a late diagnosis of simple virilizing classical CAH. Diagnosis of 21-hydroxylase deficiency was confirmed by mutation analysis of the CYP21A2 gene in all patients. Growth data were retrospectively collected from standarized preventive medical checkups at the regular pediatrician until the time of diagnosis of CAH. RESULTS: Length was 0.1 ± 0.8 SDS (mean ± SD) at birth, 0.2 ± 1 SDS at 3 months, 0.2 ± 0.9 SDS at 6 months, 0.7 ± 1 SDS at 1 year, +1.1 ± 0.9 SDS at 2 years and +1.8 ± 1.2 SDS at 4 years. At diagnosis, mean chronological age was 4.4 ± 1.6 years and height SDS was 2 ± 1.7. Bone age was accelerated (9.4 ± 4 years) at diagnosis. Signs that had led to diagnosis were pubic hair (n = 11), accelerated growth rate (n = 6) and birth of an affected sister (n = 3). Despite late start of hydrocortisone treatment, mean final height was -1 ± 0.9 SDS. Seven of 18 patients had a final height within 1 SD of target height. CONCLUSION: Height velocity is not markedly increased in untreated boys with simple virilizing CAH in the first 6 months of life, indicating that infants are relatively androgen insensitive during that period. After the first 6 months of life, growth velocity increases significantly and elevated androgens lead to advanced skeletal maturation. This observation has implications for lower hydrocortisone doses to be used in CAH children during the first 6 months of life. In addition, staying alert for clinical symptoms and signs of simple virilizing CAH is still warranted, since mild forms may be missed in newborn screening.


Asunto(s)
Andrógenos/metabolismo , Desarrollo Infantil , Virilismo/etiología , Adolescente , Desarrollo del Adolescente/efectos de los fármacos , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Hiperplasia Suprarrenal Congénita/metabolismo , Hiperplasia Suprarrenal Congénita/fisiopatología , Determinación de la Edad por el Esqueleto , Estatura/efectos de los fármacos , Estatura/genética , Desarrollo Óseo/genética , Niño , Desarrollo Infantil/efectos de los fármacos , Preescolar , Análisis Mutacional de ADN , Diagnóstico Tardío , Femenino , Humanos , Hidrocortisona/uso terapéutico , Lactante , Masculino , Registros Médicos , Estudios Retrospectivos , Esteroide 21-Hidroxilasa/genética , Virilismo/genética
4.
Vox Sang ; 100(3): 285-97, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20946535

RESUMEN

BACKGROUND AND OBJECTIVES: A human plasma-derived butyrylcholinesterase preparation manufactured on the industrial scale is described. MATERIAL AND METHODS: The human butyrylcholinesterase (hBChE) product was extensively investigated for its purity using immunological and electrophoretic methods and characterized by thorough glycoproteomic approaches. A comprehensive preclinical testing programme addressing safety and pharmacokinetic parameters supplemented the biochemical characterization. RESULTS: The high-purity hBChE preparation is tetrameric and has high specific activity and molecular integrity of the protein backbone. Acute toxicity studies and in vivo thrombogenicity studies provided evidence of a sufficient safety margin for use in humans. CONCLUSION: Extensive preclinical safety and pharmacokinetic testing confirmed that this hBChE preparation can be used for further efficacy testing as a bioscavenger for toxic organophosphate compounds in appropriate animal models and ultimately in humans.


Asunto(s)
Butirilcolinesterasa/aislamiento & purificación , Industria Farmacéutica/métodos , Butirilcolinesterasa/farmacocinética , Butirilcolinesterasa/toxicidad , Humanos , Ensayo de Materiales , Organofosfatos , Farmacocinética , Control de Calidad , Virus
5.
Horm Res Paediatr ; 75(1): 32-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20714115

RESUMEN

BACKGROUND: Linear growth is the best clinical parameter for monitoring metabolic control in classical congenital adrenal hyperplasia (CAH). OBJECTIVE: to analyze growth patterns in children with CAH diagnosed by newborn screening and treated with relatively low doses of hydrocortisone during the first year of life. PATIENTS AND METHODS: 51 patients (27 females) were diagnosed with classical CAH by newborn screening. All patients were treated with relatively low doses of hydrocortisone (9-15 mg/m(2) body surface area). 47 patients were additionally treated with fludrocortisone. RESULTS: at birth, height SDS (H-SDS) was 1.1 ± 1 in girls and 0.9 ± 1.5 in boys. After 3 months, H-SDS decreased to 0.4 ± 0.9 in girls and to 0.1 ± 1.3 in boys. Over the 3-year period, H-SDS further decreased to -0.4 ± 1.8 in girls and to -0.8 ± 1 in boys and approached the genetic height potential (target H-SDS of girls -0.5 ± 0.3 and target H-SDS of boys -0.9 ± 0.7). During the first 9 months of age, growth velocity was slightly decreased in girls (18.2 ± 1.9 cm) and boys (17.3 ± 1.6 cm) when compared to a healthy reference population (girls 19.0 ± 3.9 cm and boys 18.7 ± 4.7 cm). At the age of 3 years, bone age was appropriate for chronological age in both girls (2.7 ± 0.5 years) and boys (2.9 ± 0.5 years). CONCLUSION: birth length is above average in children with classical CAH, which might be the result of untreated hyperandrogenism in utero. With relatively low doses of hydrocortisone treatment, growth velocity decreases slightly during the first 9 months and H-SDS then approaches the genetic height potential.


Asunto(s)
Estatura/efectos de los fármacos , Desarrollo Infantil/efectos de los fármacos , Terapia de Reemplazo de Hormonas , Hidrocortisona/uso terapéutico , Tamizaje Neonatal , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Determinación de la Edad por el Esqueleto , Preescolar , Estudios de Cohortes , Monitoreo de Drogas , Quimioterapia Combinada/efectos adversos , Diagnóstico Precoz , Femenino , Fludrocortisona/efectos adversos , Fludrocortisona/uso terapéutico , Genotipo , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Hidrocortisona/administración & dosificación , Hidrocortisona/efectos adversos , Lactante , Recién Nacido , Masculino
6.
Haemophilia ; 16(102): 25-34, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20536983

RESUMEN

The development of inhibitory antibodies against factor VIII (FVIII) is the major complication in patients with haemophilia A who are treated with FVIII products. Memory B cells play an essential role in maintaining established antibody responses. Upon re-exposure to the same antigen, they are rapidly re-stimulated to proliferate and differentiate into antibody-secreting plasma cells (ASC) that secrete high-affinity antibodies. It is, therefore, reasonable to believe that memory B cells have to be eradicated or inactivated for immune tolerance induction therapy to be successful in patients with haemophilia A and FVIII inhibitors. The aim of our studies was the development of strategies to prevent FVIII-specific memory B cells from becoming re-stimulated. We established a 6-day in vitro culture system that enabled us to study the regulation of FVIII-specific murine memory-B-cell re-stimulation. We tested the impact of the blockade of co-stimulatory interactions, of different concentrations of FVIII and of ligands for toll-like receptors (TLR). The blockade of B7-CD28 and CD40-CD40 ligand interactions prevented FVIII-specific murine memory B cells from becoming re-stimulated by FVIII in vitro and in vivo. Furthermore, high concentrations of FVIII blocked re-stimulation of FVIII-specific murine memory B cells. Triggering of TLR7 amplified re-stimulation by low concentrations of FVIII and prevented blockade by high concentrations of FVIII. We conclude that we defined modulators that either amplify or inhibit the re-stimulation of FVIII-specific murine memory B cells. Currently, we are investigating whether the same modulators operate in patients with haemophilia A and FVIII inhibitors.


Asunto(s)
Linfocitos B/inmunología , Factor VIII/inmunología , Hemofilia A/inmunología , Memoria Inmunológica/inmunología , Adolescente , Adulto , Animales , Anticuerpos/inmunología , Antígenos CD/inmunología , Linfocitos B/citología , Ligando de CD40/inmunología , Diferenciación Celular , Niño , Factor VIII/administración & dosificación , Factor VIII/antagonistas & inhibidores , Hemofilia A/terapia , Humanos , Activación de Linfocitos/inmunología , Ratones , Bazo/citología , Bazo/inmunología , Adulto Joven
7.
Lab Anim ; 44(3): 211-7, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20507877

RESUMEN

The tail cut bleeding model (CUT) is routinely used in factor VIII-deficient mice to assess pharmacodynamic effects of therapeutic strategies for haemophilia A. Results from this model are highly variable, many modifications to the model are reported and at times the animals' wellbeing may be compromised by recording survival as an endpoint. We therefore investigated if the ferric chloride carotid occlusion model (COM) used for thrombosis research can be applied to enhance data quality and animal welfare in haemophilia A research. Relative dose effects and relative dose variations were calculated for the CUT and COM. The requisite sample sizes were estimated and the importance of survival rates to assess rebleeds during recovery was evaluated by correlating initial blood loss to mortality. Relative dose effects increased with higher doses in both models. The COM was more sensitive at lower doses than the CUT, had up to 82% less variation across doses and clearly showed superior accuracy. Only 5% of the sample size required for the CUT would be needed to establish non-inferiority between a specific therapeutic dose in haemophilia A mice and healthy wild-type animals. A strong statistically significant correlation was found between initial blood loss and mortality within 24 h. Our findings clearly suggest that the COM is a valid tool for assessing haemophilia A treatment in vivo. The highly reproducible data means that significantly fewer animals are required and a more humane endpoint can be used by directly assessing clot stability instead of survival rate.


Asunto(s)
Alternativas al Uso de Animales , Bienestar del Animal , Coagulantes/farmacología , Hemofilia A/tratamiento farmacológico , Proyectos de Investigación , Animales , Arteriopatías Oclusivas/inducido químicamente , Arteriopatías Oclusivas/tratamiento farmacológico , Arteriopatías Oclusivas/patología , Enfermedades de las Arterias Carótidas/inducido químicamente , Enfermedades de las Arterias Carótidas/tratamiento farmacológico , Enfermedades de las Arterias Carótidas/patología , Cloruros/toxicidad , Modelos Animales de Enfermedad , Femenino , Compuestos Férricos/toxicidad , Hemofilia A/inducido químicamente , Masculino , Ratones , Ratones Endogámicos , Ratones Noqueados , Flujo Sanguíneo Regional/efectos de los fármacos
8.
J Clin Endocrinol Metab ; 95(5): 2443-50, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20233785

RESUMEN

CONTEXT: In 21-hydroxylase (CYP21A2) deficiency (21OHD), the level of in vitro enzymatic function allows for classification of mutation groups (null, A, B, C) and prediction of disease severity. However, genital virilization in affected females correlates only weakly with CYP21A2 mutation groups, suggesting the influence of genetic modifiers. OBJECTIVE: The objective of the study was to investigate the influence of the polymorphic CAG and GGn repeats of the androgen receptor (AR) gene on the degree of genital virilization in 21OHD females. DESIGN AND PATIENTS: Design of the study was the determination of CYP21A2 genotype, degree of genital virilization (Prader stage), and X-weighted biallelic mean of AR CAG and GGn repeat length in 205 females with 21OHD. OUTCOME MEASUREMENTS: Correlation of AR CAG and GGn repeat lengths with Prader stages using nested stepwise logistic regression analysis was measured. RESULTS: CYP21A2 mutation groups null and A showed significantly higher levels of genital virilization than groups B and C (P < 0.01). However, Prader stages varied considerably within mutation groups: null, Prader I-V (median IV); A, Prader I-V (median IV); B, Prader I-V (median III); C, 0-III (median I). Mean GGn repeat length of patients was not significantly associated with Prader stages, classified as low (0-I), intermediate (II-III), or severe (IV-V) (odds ratio per repeat: 0.98, 95% confidence interval 0.71-1.35). In contrast, patients with Prader 0-I showed a trend toward longer CAG repeats without reaching statistical significance (P = 0.07, odds ratio per repeat: 0.82, 95% confidence interval 0.65-1.02). CONCLUSION: Neither CAG nor GGn repeat lengths are statistically significant modifiers of genital virilization in females with 21OHD.


Asunto(s)
Hiperplasia Suprarrenal Congénita/genética , Receptores Androgénicos/genética , Esteroide 21-Hidroxilasa/genética , Repeticiones de Trinucleótidos/genética , Virilismo/genética , Hiperplasia Suprarrenal Congénita/clasificación , Hiperplasia Suprarrenal Congénita/patología , Alelos , Cartilla de ADN , Femenino , Amplificación de Genes , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Eliminación de Secuencia , Virilismo/clasificación , Virilismo/patología
9.
Horm Res ; 72 Suppl 1: 60-4, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19940498

RESUMEN

BACKGROUND: Inflammation and glucocorticoid therapy are major factors influencing growth and bone maturation in patients with juvenile idiopathic arthritis (JIA). In addition to alterations in total bone mineral density and bone geometry, longitudinal data confirm that the main contributors to errant bone maturation in patients with JIA are reductions in muscle mass and force. Growth hormone (GH) therapy, which has shown efficacy in controlling disease, may also positively influence body composition. For several years, GH therapy has been used to treat growth retardation in patients with JIA receiving glucocorticoids. GH therapy normalizes growth velocity, increases height, bone mineral density and bone mass and changes bone geometry. Despite ongoing glucocorticoid therapy, muscle mass and bone size substantially increase with GH therapy. Increased bone size suggests improved bone stability, which may reduce fracture risk. Along with the increase in muscle mass, patients experience stabilized or slightly decreased fat mass during GH therapy. CONCLUSIONS: All these effects suggest an anabolic effect of GH therapy on bone and body composition.


Asunto(s)
Artritis Juvenil/tratamiento farmacológico , Huesos/metabolismo , Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Composición Corporal/efectos de los fármacos , Estatura/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Niño , Glucocorticoides/efectos adversos , Hormona de Crecimiento Humana/administración & dosificación , Humanos
10.
Hamostaseologie ; 29 Suppl 1: S32-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19763356

RESUMEN

Baxter has developed a recombinant therapy for treating von Willebrand's disease. Recombinant VWF is co-expressed with the rFVIII in CHO cells used to produce the rFVIII product Advate. This rVWF is used as a drug component for a rVWF-rFVIII complex drug product. CHO cells produce partially processed and partially un-processed rVWF still containing the pro-peptide. In order to make a consistent preparation containing mature and processed rVWF only rVWF is exposed to recombinant furin to remove the pro-peptide. Recombinant VWF and furin are produced under serum- and protein-free conditions. It is highly purified by a series of chromatographic steps and formulated in a protein-free buffer and has a homogeneous multimer distribution. The specific activity is higher in rVWF than in commercial plasma-derived VWF-FVIII complex products. SDS agarose electrophoretic analysis shows the presence of ultra-high molecular weight multimers. The FVIII-binding capacity and affinity of rVWF to FVIII is comparable to VWF in plasma. Carbohydrate analysis shows an intact glycosylation pattern. Recombinant VWF binds to collagen and promotes platelet adhesion under shear stress. It stabilizes endogenous FVIII in VWF-deficient knock-out mice as seen by a secondary rise in murine FVIII.


Asunto(s)
Proteínas Recombinantes/química , Factor de von Willebrand/química , Albúminas/química , Animales , Área Bajo la Curva , Células CHO , Cricetinae , Cricetulus , Modelos Animales de Enfermedad , Perros , Factor VIII/metabolismo , Semivida , Humanos , Ratones , Ratones Noqueados , Plasma/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Porcinos , Enfermedades de von Willebrand/tratamiento farmacológico , Factor de von Willebrand/genética , Factor de von Willebrand/aislamiento & purificación , Factor de von Willebrand/metabolismo , Factor de von Willebrand/farmacocinética
11.
J Thromb Haemost ; 7 Suppl 1: 92-7, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19630777

RESUMEN

MHC class II molecules are essential for shaping the CD4+ T-cell repertoire in the thymus and for selecting antigenic peptides that are presented to CD4+ T cells in the periphery. A range of different mouse models humanized for HLA class II antigens have been developed to study the regulation of MHC-class II restricted immune responses. These mouse models have been used to identify immunodominant peptides that trigger diseases and to characterize the interactions of T-cell receptors with disease-associated peptides and MHC class II molecules. Peptides presented to CD4+ T cells in these mouse models were shown to be similar to peptides presented to CD4+ T cells in patients who carry the same MHC class II haplotype. Opportunities and limitations associated with these mouse models will be discussed and the potential application of these models for understanding the regulation of antibody responses against factor VIII in hemophilia A will be indicated.


Asunto(s)
Antígenos de Histocompatibilidad Clase II/inmunología , Inmunidad , Animales , Factor VIII/inmunología , Hemofilia A/inmunología , Humanos , Ratones , Ratones Transgénicos
12.
J Thromb Haemost ; 7(7): 1134-42, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19422458

RESUMEN

BACKGROUND: von Willebrand factor (VWF) is composed of a series of multimers, the sizes of which are regulated by the plasma metalloprotease ADAMTS13. OBJECTIVE: Proteolysis of human recombinant VWF (rVWF) by ADAMTS13 present in the plasma of different species typically used as preclinical animal models was investigated to evaluate the efficacy and safety of rVWF. METHODS: Degradation of rVWF was studied in vitro under moderate denaturing conditions and was monitored by multimer analysis, residual collagen binding, and immunoblot analysis. In vivo cleavage was determined by administration of rVWF to cynomolgus monkeys, rabbits and VWF-deficient mice and subsequent analysis of plasma samples by immunoblot. Plasma ADAMTS13 levels were determined with a synthetic human VWF peptide (FRETS-VWF73). RESULTS: From the animals tested, only rabbit plasma was as efficient as human plasma in proteolysing rVWF in vitro. Mouse plasma virtually failed to cleave rVWF. Administration of human rVWF resulted in ADAMTS13-specific cleavage products in rabbits and, to a lesser extent, in cynomolgus monkeys at various doses of rVWF. Virtually no cleavage occurred in mice. ADAMTS13 activity levels in rabbit and monkey plasma were similar to those in human plasma and were not significantly altered upon infusion of rVWF up to very high doses, indicating that rVWF did not lead to an exhaustion of endogenous ADAMTS13 in both species. CONCLUSIONS: The differences in susceptibility to cleavage of rVWF by different species need to be considered when interpreting the physiology of human rVWF from results of tests in animal models.


Asunto(s)
Proteínas ADAM/metabolismo , Factor de von Willebrand/metabolismo , Proteínas ADAM/sangre , Proteína ADAMTS13 , Animales , Western Blotting , Humanos , Hidrólisis , Macaca fascicularis , Ratones , Conejos , Proteínas Recombinantes/metabolismo , Especificidad de la Especie
13.
J Pediatr Endocrinol Metab ; 21(7): 651-5, 2008 07.
Artículo en Inglés | MEDLINE | ID: mdl-18780599

RESUMEN

UNLABELLED: Hyperphagia is a frequent symptom in patients with Prader-Willi syndrome (PWS) and results in marked obesity with the risk of metabolic and cardiovascular complications. AIM: To investigate whether early diagnosis of PWS and strict dietary intervention prevents excessive weight gain in patients with PWS. PATIENTS AND METHODS: A strict fat reduced and modified carbohydrate diet consisting of 10 kcal/ cm height was provided to nine patients (seven female, two male) diagnosed early with PWS (group A). Patients were prospectively followed at our center with follow-up visits every three months. Eight patients with late diagnosis of PWS served as controls (group B). Body mass index (BMI) SDS and height SDS were compared between these two groups over a ten-year period. RESULTS: At the age of two years height SDS and BMI SDS were significantly lower in group A (-2.9 vs -1.2, p <0.05, and BMI SDS -0.1 vs +1.8, p < 0.05). After ten years BMI SDS increased significantly to +1.2 SDS in group A, but was still significantly lower than in group B (BMI SDS +2.4), p <0.005. Patients without restrictive diet were significantly taller than patients on the diet (height SDS group A -2.8 vs group B -1.3, p < 0.05). CONCLUSION: Early dietary treatment starting at the second year of life and continued until the age of ten years is effective in avoiding excessive weight gain in patients with PWS, but results in shorter stature. Therefore growth hormone may be a useful additional treatment in these patients.


Asunto(s)
Dieta , Obesidad/complicaciones , Obesidad/prevención & control , Síndrome de Prader-Willi/complicaciones , Adolescente , Antropometría , Índice de Masa Corporal , Niño , Preescolar , Ingestión de Energía , Femenino , Estudios de Seguimiento , Humanos , Hiperfagia/etiología , Hiperfagia/psicología , Lactante , Recién Nacido , Masculino
14.
Klin Padiatr ; 220(5): 287-90, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18716981

RESUMEN

BACKGROUND: Extreme hyponatremia (<105 mmol/l) has rarely been reported in infants. It is potentially life-threatening and requires intensive care treatment. PATIENT: We report on a male infant with absence of weight gain from birth to day 33 of life despite adequate nutrition. On admission serum sodium and potassium were 104 and 5.9 mmol/L respectively. The infant's physical status revealed dehydration, but normal activity with no apparent neurological, circulatory or respiratory impairment. MAIN RESULTS: Global adrenocortical insufficiency was diagnosed and treated with hormonal substitution in addition to intravenous application of fluid, glucose and electrolytes. The rise of serum sodium was carefully monitored and adjusted to a target rate of 0.5 mmol/L/h. X-linked adrenal hypoplasia congenita (X-AHC) was confirmed by the identification of a novel nonsense NR0B1 (DAX-1) mutation (W236X). CONCLUSIONS: X-AHC in infants may present as failure to thrive despite adequate nutrition. Extreme hyponatremia may be associated with little symptoms if developing slowly. Rehydration and slow correction of serum sodium with solutions containing less sodium than normal saline is essential.


Asunto(s)
Insuficiencia Suprarrenal/genética , Proteínas de Unión al ADN/genética , Hiponatremia/etiología , Mutación , Receptores de Ácido Retinoico/genética , Proteínas Represoras/genética , Enfermedad de Addison/diagnóstico , Enfermedad de Addison/genética , Enfermedad de Addison/terapia , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/terapia , Receptor Nuclear Huérfano DAX-1 , Insuficiencia de Crecimiento/etiología , Fluidoterapia , Humanos , Hiperpotasemia/etiología , Recién Nacido , Masculino , Potasio/sangre , Sodio/sangre
15.
Vox Sang ; 94(4): 334-41, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18266779

RESUMEN

BACKGROUND AND OBJECTIVES: Previous studies have presented evidence that human immunoglobulin G preparations for intravenous use contain antibodies directed against the death receptor Fas (CD95). The function of these antibodies was described as either antagonistic or agonistic; therefore, inhibiting or stimulating Fas-dependent apoptosis. Based on these reports, we asked whether the proportion of antagonistic and agonistic anti-Fas activities differs between different lots of intravenous immunoglobulin (IVIG). Variations between lots would open the possibility to preselect suitable lots of IVIG for different therapeutic purposes. MATERIALS AND METHODS: Eleven lots of IVIG were tested for their ability to induce or inhibit Fas-dependent apoptosis. The biological significance of anti-Fas antibodies was confirmed by including anti-Fas antibodies purified from IVIG and IVIG depleted of anti-Fas antibodies in the study. RESULTS: All 11 lots inhibited FasL-induced apoptosis. In addition, five lots stimulated apoptosis in the absence of FasL. Depletion of anti-Fas antibodies from IVIG abolished the capacity of IVIG to inhibit FasL-induced apoptosis, but reduced the ability to induce apoptosis only slightly. CONCLUSION: The inhibition of FasL-induced apoptosis by IVIG is because of the presence of antagonistic anti-Fas antibodies. The activity of these antibodies differs considerably between different lots. On the other hand, the induction of apoptosis by IVIG is probably because of the concerted action of a range of different antibodies. The variation in the proportion of stimulating and inhibiting anti-Fas activities between different lots of IVIG opens the possibility to preselect suitable lots for different therapeutic purposes.


Asunto(s)
Inmunoglobulinas Intravenosas/análisis , Factores Inmunológicos/análisis , Receptor fas/inmunología , Apoptosis/efectos de los fármacos , Humanos , Inmunoglobulinas Intravenosas/inmunología , Inmunoglobulinas Intravenosas/farmacología , Factores Inmunológicos/inmunología , Factores Inmunológicos/farmacología , Células Jurkat , Queratinocitos , Receptor fas/agonistas , Receptor fas/antagonistas & inhibidores
16.
Vox Sang ; 94(3): 184-192, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18167162

RESUMEN

BACKGROUND AND OBJECTIVES: A new 10% liquid human intravenous immunoglobulin (US trade name: Gammagard Liquid; European trade name: KIOVIG) manufactured by a process with three dedicated pathogen inactivation/removal steps (solvent/detergent treatment, 35-nm nanofiltration and low pH/elevated temperature incubation) was developed. The ability of the manufacturing process to inactivate/remove viruses and prions was investigated. MATERIALS AND METHODS: Virus and prion removal capacities were assessed with down-scale spiking experiments, validated for equivalence to the large-scale process. RESULTS: Lipid-enveloped viruses were completely inactivated/removed by each of the three dedicated virus clearance steps, and for human immunodeficiency virus 1 (HIV-1) and pseudorabies virus (PRV), also by the upstream cold ethanol fractionation step. Relevant non-enveloped viruses [i.e. hepatitis A virus (HAV) and parvovirus B19 (B19V)] were effectively removed by nanofiltration and the cold ethanol fractionation step, and partial inactivation of non-enveloped viruses was achieved by low pH incubation. Overall log reduction factors were > 20.0 for HIV-1, > 18.1 for bovine viral diarrhoea virus, > 16.3 for West Nile virus, > 10.0 for influenza A virus subtype H5N1, > 21.8 for PRV, 12.0 for HAV, > 12.1 for encephalomyocarditis virus, 10.6 for B19V and 10.3 for mice minute virus. Prions (Western blot assay) were completely removed (> or = 3.2 mean log reduction) by a step of the cold ethanol fractionation process. CONCLUSIONS: Introducing three dedicated virus-clearance steps in the manufacturing process of immunoglobulins from human plasma provides high margins of safety.


Asunto(s)
Inmunoglobulinas Intravenosas/aislamiento & purificación , Priones/aislamiento & purificación , Virus/aislamiento & purificación , Efecto Citopatogénico Viral , Detergentes , Contaminación de Medicamentos/prevención & control , Humanos , Concentración de Iones de Hidrógeno , Filtros Microporos , Reacción en Cadena de la Polimerasa , Seguridad , Solventes , Temperatura , Ultrafiltración , Inactivación de Virus , Virus/genética
17.
Neuropediatrics ; 38(4): 197-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18058628

RESUMEN

Hashimoto encephalopathy (HE) is a rare steroid-responsive encephalopathy associated with elevated antithyroid antibodies and is a well recognised complication of autoimmune thyroid disease. The clinical picture is pleomorphic, presenting with variable symptoms like coma, seizures, neuropsychiatric changes (impairment of cognitive functions, behavioural and mood disturbances, hallucinations) or focal neurological deficits. HE is mainly diagnosed in adults, but also a rare differential diagnosis of encephalopathy or epilepsy in children. The diagnosis is often overlooked at presentation but is crucial as it is a treatable disease. We report on the youngest patient described up to now presenting with progressive epilepsy resistant to anticonvulsive treatment and unclear encephalopathy related to Hashimoto thyroiditis.


Asunto(s)
Encefalopatías/complicaciones , Coma/etiología , Enfermedad de Hashimoto/complicaciones , Trastornos Psicóticos/etiología , Convulsiones/etiología , Niño , Femenino , Humanos
18.
Diabetologia ; 50(12): 2417-23, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17898991

RESUMEN

AIMS: Because reduction in baroreceptor sensitivity (BRS) has been associated with hypertension in the normal population and with increased cardiovascular morbidity and mortality in patients with diabetes mellitus, we measured BRS in a patient cohort of children with type 1 diabetes mellitus. METHODS: Two hundred and eight children (150 patients with type 1 diabetes mellitus, mean age 13.9 +/- 2.8 years, 70 boys, mean HbA(1c) 7.8 +/- 1.4%; and 58 healthy controls, mean age 14.1 +/- 3.1 years, 32 boys) were studied. BRS and heart rate variability (HRV) were analysed from a short-time ECG and BP recording using the sequence method (BRS) and the frequency domain method (HRV). RESULTS: There were 111 of 150 patients (74%) and 5 of 58 controls (8.6%) that showed impaired BRS. Mean BRS differed significantly between patients and controls (18.4 +/- 7.2 vs 25.8 +/- 8.2 ms/mm, p < 0.001). BRS correlated inversely with systolic BP (r = -0.23, p = 0.009) and was related to diabetes duration (r = -0.194, p = 0.027). Analysis of HRV showed greater sympathetic and less parasympathetic influence in patients than in controls (low frequency/high frequency ratio 1.3 +/- 0.8 vs 0.9 +/- 0.6, p < 0.05); the low frequency/high frequency ratio was inversely correlated with BRS (r = -0.28, p = 0.001). CONCLUSIONS/INTERPRETATION: Diabetic children show reduced BRS. In our patient group, the single risk factor for this finding was found to be the disease duration. The degree of BRS impairment was related to the degree of autonomic dysbalance.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/etiología , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/fisiopatología , Hipertensión/etiología , Adolescente , Adulto , Barorreflejo/fisiología , Presión Sanguínea/fisiología , Estudios de Casos y Controles , Niño , Estudios Transversales , Progresión de la Enfermedad , Electrocardiografía , Femenino , Hemoglobina Glucada/análisis , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Factores de Tiempo
19.
Vox Sang ; 92(1): 42-55, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17181590

RESUMEN

BACKGROUND AND OBJECTIVES: The ultimate goal was to generate an industrial-scale process suitable to produce a high-yield, safe and stable immunoglobulin G (IgG) preparation for intravenous administration, which is ready to use for customer convenience. This new liquid 10% IgG preparation (IGIV 10%) was compared to Gammagard SD, a licenced lyophilized immunoglobulin in biochemical and preclinical testing. MATERIALS AND METHODS: The new process, which includes three dedicated virus clearance steps, is a streamlined combination of the currently applied and well-established manufacturing procedures. The biochemical characterization is done by standard methods focusing on purity, integrity and functionality of the preparation. Efficacy is demonstrated in vivo by mouse protection testing and in vitro by opsonization and protein A affinity chromatography. Pharmacokinetics in rats is evaluated after a single intravenous dose. The anaphylactoid potential is determined in rats and in guinea pigs, while thrombogenicity is assessed in a rabbit model. The influence of the products on vital functions is tested on dogs, while acute toxicity studies are carried out on mice and rats. RESULTS: The biochemical characterization data demonstrate the high purity of monomeric IgG in the product. The mouse protection test showed that the protective activity against systemic bacterial infections of IGIV 10% is at least as good as the reference Gammagard SD. This result is supported by the broad spectrum of antibodies in high titres against bacteria and viruses and the high functional integrity of the IgG molecule (> or = 90% functionally intact IgG) in IGIV 10%. The opsonic activity of all IGIV 10% lots is similar to the one of the reference Gammagard SD. In safety and thrombogenicity studies, no adverse effects of IGIV 10% were observed. Pharmacokinetic studies showed no statistically significant differences between the two products. In the acute toxicity animal studies, IGIV 10% compared favourably to the reference Gammagard SD. CONCLUSIONS: The new manufacturing process enables the production of a highly purified IgG preparation for intravenous administration. The product has an IgG subclass distribution similar to plasma and contains a broad spectrum of functionally intact antibodies. Preclinical studies demonstrate that the liquid IGIV 10% combines excellent qualities of efficacy, safety and tolerability.


Asunto(s)
Descontaminación/métodos , Desinfección/métodos , Inmunoglobulinas Intravenosas/aislamiento & purificación , Factores Inmunológicos/aislamiento & purificación , Preparaciones Farmacéuticas/aislamiento & purificación , Animales , Perros , Evaluación Preclínica de Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Inmunoglobulinas Intravenosas/química , Inmunoglobulinas Intravenosas/farmacocinética , Factores Inmunológicos/química , Factores Inmunológicos/farmacocinética , Ratones , Preparaciones Farmacéuticas/sangre , Preparaciones Farmacéuticas/química , Conejos , Ratas , Resultado del Tratamiento
20.
J Pediatr Endocrinol Metab ; 19(8): 987-93, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16995583

RESUMEN

Short stature and ovarian failure are the main features in Ullrich-Turner syndrome (UTS). The aim of this retrospective analysis was to evaluate the influence of age at initiation of puberty on final height. Sixty-five girls were treated with growth hormone (GH) and had a final height of 150.6 +/- 5.7 cm; 12/65 entered puberty spontaneously. A non-GH treated group of 12 girls with UTS reached a final height of 147.3 +/- 6.6 cm. Subdividing the GH treated group (n = 53) based on the age at induction of puberty, before or after 13 years, there was no significant difference in final height. Final height was affected by the age at which GH treatment was initiated, height SDS at the beginning of puberty, and by the duration of GH therapy. Therefore, early treatment with GH for short stature in UTS should be attempted so that an age adequate initiation of puberty will be feasible.


Asunto(s)
Estatura/fisiología , Pubertad/fisiología , Síndrome de Turner/fisiopatología , Adolescente , Estatura/efectos de los fármacos , Niño , Femenino , Hormona de Crecimiento Humana/uso terapéutico , Humanos , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Síndrome de Turner/tratamiento farmacológico
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