Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Pediatr Emerg Care ; 36(3): e156-e159, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29112539

RESUMEN

OBJECTIVES: To inform selective and efficient use of appendix ultrasound (US) beyond adult parameters of body mass index (BMI) of less than 25 kg/m, we correlate abdominal wall thickness (AWT) with age and BMI to generate parameters for male and female children. Information presented in chart format can aid in the decision to utilize US for the evaluation of appendicitis. METHODS: In this observational study, 1600 pediatric computed tomography scans of the abdomen and pelvis were analyzed to obtain measurements of AWT in the right lower quadrant. Measurements were correlated by patient age, BMI, and sex. Results and consensus-based recommendations were presented in chart format with color-coded groupings to allow for convenient referencing in the clinical setting. RESULTS: One thousand four hundred eighty-eight computed tomography scans and AWT measurements were included. All age groups with BMI of less than 25 kg/m and all male and female groups younger than 6 years regardless of BMI had median AWT of less than 4 cm resulting in strong recommendation for US. Males older than 6 years and all female age groups with BMI of greater than 30 kg/m and female older than 15 years and BMI of greater than 25 kg/m had AWT of more than 5 cm resulting in low recommendation for US. CONCLUSIONS: While the BMI cutoff standard of less than 25 kg/m for usefulness of appendix US holds in the adult population, our data expand the acceptable range in children younger than 9 years regardless of BMI and male children with BMI up to 30 kg/m. Female children younger than 15 years with a BMI up to 30 kg/m may also be amenable to right lower quadrant US based on AWT. These parameters inform selective and efficient use of US for appendix evaluation.


Asunto(s)
Pared Abdominal/fisiología , Apendicitis/diagnóstico por imagen , Apéndice/diagnóstico por imagen , Adolescente , Índice de Masa Corporal , Niño , Preescolar , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos X , Ultrasonografía
2.
Mol Phylogenet Evol ; 109: 388-403, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28119108

RESUMEN

The tortricid moth genus Syndemis has ten described species, with two polyphagous species in Europe and North America respectively. We sequenced five nuclear and four mitochondrial genes for Syndemis samples across both continents and discovered unexpected, extensive diversification restricted to California. DNA evidence supports five new, undescribed, species endemic to California, while the rest of North America and Europe have only one species each. Further, the nuclear genes are less variable and yield contrasting phylogenetic signal compared to mitochondrial DNA for basal relationships between taxa across the genus. Such conflict strongly suggests that male and female moths exhibit radically different levels of philopatry. Our results highlight the importance of sex-specific behavior, and the need for inclusion of multiple genes to fully understand species boundaries, their causes, and the process of speciation. While mtDNA introgression often is invoked to explain incongruous haplotype distributions, our study shows that nuclear DNA selective sweeps, or swamping, can occur while mtDNA and ecology preserve an ancient divergence that is not discernable in nuclear DNA. This study further demonstrates that diversification of herbivores may occur on relictual, declining hostplants, which contrasts with the dominant co-speciation model.


Asunto(s)
Especiación Genética , Mariposas Nocturnas/fisiología , Animales , Secuencia de Bases , California , ADN Mitocondrial , Femenino , Genes Mitocondriales , Haplotipos , Masculino , Mariposas Nocturnas/genética , Filogenia , Análisis de Secuencia de ADN , Caracteres Sexuales , Árboles/parasitología
3.
N Engl J Med ; 369(24): 2313-23, 2013 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-24304002

RESUMEN

BACKGROUND: Prophylactic factor replacement in patients with hemophilia B improves outcomes but requires frequent injections. A recombinant factor IX Fc fusion protein (rFIXFc) with a prolonged half-life was developed to reduce the frequency of injections required. METHODS: We conducted a phase 3, nonrandomized, open-label study of the safety, efficacy, and pharmacokinetics of rFIXFc for prophylaxis, treatment of bleeding, and perioperative hemostasis in 123 previously treated male patients. All participants were 12 years of age or older and had severe hemophilia B (endogenous factor IX level of ≤2 IU per deciliter, or ≤2% of normal levels). The study included four treatment groups: group 1 received weekly dose-adjusted prophylaxis (50 IU of rFIXFc per kilogram of body weight to start), group 2 received interval-adjusted prophylaxis (100 IU per kilogram every 10 days to start), group 3 received treatment as needed for bleeding episodes (20 to 100 IU per kilogram), and group 4 received treatment in the perioperative period. A subgroup of group 1 underwent comparative sequential pharmacokinetic assessments of recombinant factor IX and rFIXFc. The primary efficacy end point was the annualized bleeding rate, and safety end points included the development of inhibitors and adverse events. RESULTS: As compared with recombinant factor IX, rFIXFc exhibited a prolonged terminal half-life (82.1 hours) (P<0.001). The median annualized bleeding rates in groups 1, 2, and 3 were 3.0, 1.4, and 17.7, respectively. In group 2, 53.8% of participants had dosing intervals of 14 days or more during the last 3 months of the study. In groups 1, 2 and 3, 90.4% of bleeding episodes resolved after one injection. Hemostasis was rated as excellent or good during all major surgeries. No inhibitors were detected in any participants receiving rFIXFc; in groups 1, 2, and 3, 73.9% of participants had at least one adverse event, and serious adverse events occurred in 10.9% of participants. These events were mostly consistent with those expected in the general population of patients with hemophilia. CONCLUSIONS: Prophylactic rFIXFc, administered every 1 to 2 weeks, resulted in low annualized bleeding rates in patients with hemophilia B. (Funded by Biogen Idec; ClinicalTrials.gov number, NCT01027364.).


Asunto(s)
Factor IX/uso terapéutico , Hemofilia B/tratamiento farmacológico , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Factor IX/efectos adversos , Factor IX/farmacocinética , Femenino , Semivida , Hemofilia B/metabolismo , Hemorragia/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/efectos adversos , Proteínas Recombinantes de Fusión/farmacocinética , Adulto Joven
4.
Blood ; 123(3): 317-25, 2014 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-24227821

RESUMEN

This phase 3 pivotal study evaluated the safety, efficacy, and pharmacokinetics of a recombinant FVIII Fc fusion protein (rFVIIIFc) for prophylaxis, treatment of acute bleeding, and perioperative hemostatic control in 165 previously treated males aged ≥12 years with severe hemophilia A. The study had 3 treatment arms: arm 1, individualized prophylaxis (25-65 IU/kg every 3-5 days, n = 118); arm 2, weekly prophylaxis (65 IU/kg, n = 24); and arm 3, episodic treatment (10-50 IU/kg, n = 23). A subgroup compared recombinant FVIII (rFVIII) and rFVIIIFc pharmacokinetics. End points included annualized bleeding rate (ABR), inhibitor development, and adverse events. The terminal half-life of rFVIIIFc (19.0 hours) was extended 1.5-fold vs rFVIII (12.4 hours; P < .001). Median ABRs observed in arms 1, 2, and 3 were 1.6, 3.6, and 33.6, respectively. In arm 1, the median weekly dose was 77.9 IU/kg; approximately 30% of subjects achieved a 5-day dosing interval (last 3 months on study). Across arms, 87.3% of bleeding episodes resolved with 1 injection. Adverse events were consistent with those expected in this population; no subjects developed inhibitors. rFVIIIFc was well-tolerated, had a prolonged half-life compared with rFVIII, and resulted in low ABRs when dosed prophylactically 1 to 2 times per week.


Asunto(s)
Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Esquema de Medicación , Factor VIII/farmacocinética , Hemorragia/tratamiento farmacológico , Hemorragia/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/farmacocinética , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
5.
BMC Evol Biol ; 15: 73, 2015 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-25907684

RESUMEN

BACKGROUND: The Mormon Metalmark (Apodemia mormo) species complex occurs as isolated and phenotypically variable colonies in dryland areas across western North America. Lange's Metalmark, A. m. langei, one of the 17 subspecies taxonomically recognized in the complex, is federally listed under the U.S. Endangered Species Act of 1973. Metalmark taxa have traditionally been described based on phenotypic and ecological characteristics, and it is unknown how well this nomenclature reflects their genetic and evolutionary distinctiveness. Genetic variation in six microsatellite loci and mitochondrial cytochrome oxidase subunit I sequence was used to assess the population structure of the A. mormo species complex across 69 localities, and to evaluate A. m. langei's qualifications as an Evolutionarily Significant Unit. RESULTS: We discovered substantial genetic divergence within the species complex, especially across the Continental Divide, with population genetic structure corresponding more closely with geographic proximity and local isolation than with taxonomic divisions originally based on wing color and pattern characters. Lange's Metalmark was as genetically divergent as several other locally isolated populations in California, and even the unique phenotype that warranted subspecific and conservation status is reminiscent of the morphological variation found in some other populations. CONCLUSIONS: This study is the first genetic treatment of the A. mormo complex across western North America and potentially provides a foundation for reassessing the taxonomy of the group. Furthermore, these results illustrate the utility of molecular markers to aid in demarcation of biological units below the species level. From a conservation point of view, Apodemia mormo langei's diagnostic taxonomic characteristics may, by themselves, not support its evolutionary significance, which has implications for its formal listing as an Endangered Species.


Asunto(s)
Evolución Biológica , Mariposas Diurnas/clasificación , Mariposas Diurnas/genética , Especies en Peligro de Extinción , Animales , Conservación de los Recursos Naturales , ADN Mitocondrial/genética , Variación Genética , Genética de Población , Repeticiones de Microsatélite , Filogenia , Estados Unidos
6.
Hum Mol Genet ; 22(9): 1903-10, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23372042

RESUMEN

Human genetic variation contributes to differences in susceptibility to HIV-1 infection. To search for novel host resistance factors, we performed a genome-wide association study (GWAS) in hemophilia patients highly exposed to potentially contaminated factor VIII infusions. Individuals with hemophilia A and a documented history of factor VIII infusions before the introduction of viral inactivation procedures (1979-1984) were recruited from 36 hemophilia treatment centers (HTCs), and their genome-wide genetic variants were compared with those from matched HIV-infected individuals. Homozygous carriers of known CCR5 resistance mutations were excluded. Single nucleotide polymorphisms (SNPs) and inferred copy number variants (CNVs) were tested using logistic regression. In addition, we performed a pathway enrichment analysis, a heritability analysis, and a search for epistatic interactions with CCR5 Δ32 heterozygosity. A total of 560 HIV-uninfected cases were recruited: 36 (6.4%) were homozygous for CCR5 Δ32 or m303. After quality control and SNP imputation, we tested 1 081 435 SNPs and 3686 CNVs for association with HIV-1 serostatus in 431 cases and 765 HIV-infected controls. No SNP or CNV reached genome-wide significance. The additional analyses did not reveal any strong genetic effect. Highly exposed, yet uninfected hemophiliacs form an ideal study group to investigate host resistance factors. Using a genome-wide approach, we did not detect any significant associations between SNPs and HIV-1 susceptibility, indicating that common genetic variants of major effect are unlikely to explain the observed resistance phenotype in this population.


Asunto(s)
Resistencia a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Infecciones por VIH/genética , Hemofilia A/genética , Adulto , Variaciones en el Número de Copia de ADN , Epistasis Genética , Factor VIII/uso terapéutico , Femenino , Eliminación de Gen , Predisposición Genética a la Enfermedad , Seropositividad para VIH/genética , Heterocigoto , Homocigoto , Humanos , Modelos Logísticos , Masculino , Metaanálisis como Asunto , Persona de Mediana Edad , Fenotipo , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Receptores CCR5/genética , Receptores CCR5/metabolismo
7.
Br J Haematol ; 168(1): 113-23, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25209873

RESUMEN

In the phase 3 B-LONG [Recombinant Factor IX Fc Fusion Protein (rFIXFc) in Subjects with Haemophilia B] study, rFIXFc dosed every 1-2 weeks was safe and efficacious in previously treated subjects with haemophilia B. To date, there are no evaluations of transitioning from conventional to long-acting factor IX (FIX) prophylaxis. This post-hoc analysis of B-LONG subjects compared prophylaxis with other FIX products and rFIXFc. Pre- and on-study data were analysed to assess dosing regimen, weekly FIX consumption and annualized bleeding rates (ABRs). Population pharmacokinetics models were used to generate FIX activity profiles with rFIXFc and recombinant FIX prophylaxis. Thirty-nine subjects, previously treated prophylactically, were evaluated. Prior to study, most subjects (69·2%) received twice-weekly FIX infusions; on study, subjects infused rFIXFc once every 1-2 weeks with c. 30-50% reductions in weekly consumption. On-study estimated mean ABRs were lower than pre-study estimated mean ABRs. Models predicted that rFIXFc administered 50 iu/kg weekly and 100 iu/kg every 10 d would maintain steady-state FIX trough levels ≥1 iu/dl in 95·4% and 89·2% of subjects, respectively. These results indicate that patients receiving rFIXFc prophylaxis can markedly reduce infusion frequency and FIX consumption, have a greater likelihood of maintaining FIX activity >1 iu/dl and experience fewer bleeding episodes compared with prior FIX prophylaxis.


Asunto(s)
Quimioprevención , Factor IX/uso terapéutico , Hemofilia B/tratamiento farmacológico , Hemorragia/prevención & control , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Adulto , Anciano , Niño , Sustitución de Medicamentos , Factor IX/farmacología , Hemofilia B/complicaciones , Hemorragia/etiología , Humanos , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/farmacología , Resultado del Tratamiento , Adulto Joven
8.
Br J Haematol ; 168(1): 124-34, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25208598

RESUMEN

In the phase 3 B-LONG (Recombinant Factor IX Fc Fusion Protein [rFIXFc] in Subjects With Haemophilia B) study, rFIXFc demonstrated a prolonged half-life compared with recombinant factor IX (rFIX), and safety and efficacy for prophylaxis and treatment of bleeding in subjects with moderately-severe to severe haemophilia B. In this B-LONG sub-analysis, rFIXFc was evaluated for efficacy in subjects requiring major surgery. Dosing was investigator-determined. Assessments included dosing, consumption, bleeding, transfusions and haemostatic response. A population pharmacokinetics model of rFIXFc was used to predict FIX activity. Twelve subjects underwent 14 major surgeries (including 11 orthopaedic surgeries); most subjects (11/12) received rFIXFc prophylaxis before surgery (range, ~2 weeks-12 months). Investigators/surgeons rated haemostatic responses as excellent (n = 13) or good (n = 1). In most surgeries (85·7%), haemostasis from the pre-surgical dose until the end of surgery was maintained with a single rFIXFc infusion. Blood loss was consistent with similar surgeries in subjects without haemophilia. The strong correlation (R(2) = 0·9586, P < 0·001) between observed and population pharmacokinetic model-predicted FIX activity suggests surgery did not impact rFIXFc pharmacokinetics. No unique safety concerns or inhibitors were observed. In conclusion, rFIXFc was safe and efficacious, with prolonged dosing intervals and low consumption, when used perioperatively in haemophilia B. Surgery did not appear to alter rFIXFc pharmacokinetics.


Asunto(s)
Quimioprevención , Factor IX/uso terapéutico , Hemofilia B/tratamiento farmacológico , Hemofilia B/cirugía , Hemorragia/prevención & control , Atención Perioperativa , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Adulto , Pruebas de Coagulación Sanguínea , Manejo de la Enfermedad , Factor IX/administración & dosificación , Factor IX/farmacocinética , Hemofilia B/complicaciones , Hemorragia/etiología , Hemostasis Quirúrgica , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/farmacocinética , Resultado del Tratamiento , Adulto Joven
9.
Blood ; 122(22): 3568-74, 2013 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-24065241

RESUMEN

Hemophilia is caused by a functional deficiency of one of the coagulation proteins. Therapy for no other group of genetic diseases has seen the progress that has been made for hemophilia over the past 40 years, from a life expectancy in 1970 of ∼20 years for a boy born with severe hemophilia to essentially a normal life expectancy in 2013 with current prophylaxis therapy. However, these therapies are expensive and require IV infusions 3 to 4 times each week. These are exciting times for hemophilia because several new technologies that promise extended half-lives for factor products, with potential for improvements in quality of life for persons with hemophilia, are in late-phase clinical development.


Asunto(s)
Hemofilia A/terapia , Anticuerpos Neutralizantes/biosíntesis , Factores de Coagulación Sanguínea/química , Factores de Coagulación Sanguínea/inmunología , Factores de Coagulación Sanguínea/uso terapéutico , Factor IX/química , Factor IX/uso terapéutico , Factor VIII/química , Factor VIII/uso terapéutico , Hemofilia A/sangre , Hemofilia A/genética , Humanos , Masculino , Peróxidos/uso terapéutico , Polietilenglicoles/química , Polivinilos/uso terapéutico , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/uso terapéutico
10.
Transfusion ; 55(1): 45-50, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25070582

RESUMEN

BACKGROUND: Patients with congenital Factor XIII (FXIII) deficiency have impaired fibrin stabilization and are at high risk for surgical bleeding. Data regarding the use of FXIII concentrates before and during surgery are lacking. The objective of this study was to report the use of plasma-derived FXIII concentrate (Corifact in the United States; Fibrogammin P in other countries) in patients with congenital FXIII deficiency undergoing surgical procedures. STUDY DESIGN AND METHODS: FXIII concentrate at preoperative doses ranging from 25 to 40 U/kg was administered to six patients with congenital FXIII deficiency undergoing major or minor surgeries. RESULTS: FXIII concentrate was administered immediately before surgery for five surgical cases; three of these patients achieved excellent hemostasis during and after surgery, while two had intraoperative bleeding. In one surgical case, a regular prophylactic dose of FXIII concentrate was administered to the patient 1 week before minor surgery. FXIII concentrate provided rapid replacement of FXIII activity. In all but one of the patients given a dose of FXIII designed to increase FXIII levels more than 50%, there was satisfactory intraoperative and postoperative hemostasis. One patient undergoing aortic valve replacement on cardiopulmonary bypass (CPB) was the exception. Intraoperative bleeding in this patient was associated with lower-than-expected blood levels of FXIII. CONCLUSION: Preoperative plasma-derived FXIII concentrate allowed for sufficient hemostasis in most patients with FXIII deficiencies. Additional doses were necessary to achieve hemostasis in one patient who underwent a CPB procedure.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Deficiencia del Factor XIII/terapia , Factor XIII/uso terapéutico , Hemorragia Posoperatoria/prevención & control , Cuidados Preoperatorios/métodos , Adolescente , Adulto , Anciano , Anticoagulantes/uso terapéutico , Deficiencia del Factor XIII/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Bucal/prevención & control , Trombosis/prevención & control , Warfarina/uso terapéutico
11.
Blood ; 119(13): 3031-7, 2012 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-22223821

RESUMEN

Current factor VIII (FVIII) products display a half-life (t(1/2)) of ∼ 8-12 hours, requiring frequent intravenous injections for prophylaxis and treatment of patients with hemophilia A. rFVIIIFc is a recombinant fusion protein composed of a single molecule of FVIII covalently linked to the Fc domain of human IgG(1) to extend circulating rFVIII t(1/2). This first-in-human study in previously treated subjects with severe hemophilia A investigated safety and pharmacokinetics of rFVIIIFc. Sixteen subjects received a single dose of rFVIII at 25 or 65 IU/kg followed by an equal dose of rFVIIIFc. Most adverse events were unrelated to study drug. None of the study subjects developed anti-rFVIIIFc antibodies or inhibitors. Across dose levels, compared with rFVIII, rFVIIIFc showed 1.54- to 1.70-fold longer elimination t(1/2), 1.49- to 1.56-fold lower clearance, and 1.48- to 1.56-fold higher total systemic exposure. rFVIII and rFVIIIFc had comparable dose-dependent peak plasma concentrations and recoveries. Time to 1% FVIII activity above baseline was ∼ 1.53- to 1.68-fold longer than rFVIII across dose levels. Each subject showed prolonged exposure to rFVIIIFc relative to rFVIII. Thus, rFVIIIFc may offer a viable therapeutic approach to achieve prolonged hemostatic protection and less frequent dosing in patients with hemophilia A. This trial was registered at www.clinicaltrials.gov as NCT01027377.


Asunto(s)
Factor VIII/farmacocinética , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Receptores Fc/uso terapéutico , Proteínas Recombinantes de Fusión/farmacocinética , Proteínas Recombinantes de Fusión/uso terapéutico , Adulto , Relación Dosis-Respuesta a Droga , Factor VIII/administración & dosificación , Factor VIII/efectos adversos , Semivida , Hemofilia A/sangre , Hemofilia A/metabolismo , Humanos , Fragmentos Fc de Inmunoglobulinas/administración & dosificación , Fragmentos Fc de Inmunoglobulinas/efectos adversos , Bombas de Infusión , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Receptores Fc/administración & dosificación , Receptores Fc/metabolismo , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/efectos adversos , Factores de Tiempo , Adulto Joven , Factor de von Willebrand/análisis
12.
Blood ; 119(3): 666-72, 2012 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-22110246

RESUMEN

Current factor IX (FIX) products display a half-life (t(1/2)) of ∼ 18 hours, requiring frequent intravenous infusions for prophylaxis and treatment in patients with hemophilia B. This open-label, dose-escalation trial in previously treated adult subjects with hemophilia B examined the safety and pharmacokinetics of rFIXFc. rFIXFc is a recombinant fusion protein composed of FIX and the Fc domain of human IgG(1), to extend circulating time. Fourteen subjects received a single dose of rFIXFc; 1 subject each received 1, 5, 12.5, or 25 IU/kg, and 5 subjects each received 50 or 100 IU/kg. rFIXFc was well tolerated, and most adverse events were mild or moderate in intensity. No inhibitors were detected in any subject. Dose-proportional increases in rFIXFc activity and Ag exposure were observed. With baseline subtraction, mean activity terminal t(1/2) and mean residence time for rFIXFc were 56.7 and 71.8 hours, respectively. This is ∼ 3-fold longer than that reported for current rFIX products. The incremental recovery of rFIXFc was 0.93 IU/dL per IU/kg, similar to plasma-derived FIX. These results show that rFIXFc may offer a viable therapeutic approach to achieve prolonged hemostatic protection and less frequent dosing in patients with hemophilia B. The trial was registered at www.clinicaltrials.gov as NCT00716716.


Asunto(s)
Factor IX/metabolismo , Hemofilia B/metabolismo , Hemofilia B/terapia , Proteínas Recombinantes de Fusión/uso terapéutico , Adolescente , Adulto , Anciano , Femenino , Semivida , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/farmacocinética , Seguridad , Adulto Joven
13.
Transfusion ; 53(6): 1217-25, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22998193

RESUMEN

BACKGROUND: Parvovirus B19 (B19V) is a small, nonenveloped virus that typically causes a benign flu-like illness that occurs most frequently in childhood. The virus is resistant to current viral inactivation steps used in the manufacture of antihemophilic factor concentrates and B19V transmission through these products has been documented. Since 2000, B19V nucleic acid test (NAT) screening of plasma pools has been implemented to further decrease the viral burden in these products, but no study has examined populations using these products to assess the impact of the screening on B19V transmission. STUDY DESIGN AND METHODS: Blood specimens obtained from participants of a surveillance system established in federally supported specialized bleeding disorders clinics were used in a B19V seroprevalence study. RESULTS: A total of 1643 specimens from 1043 participants age 2 to 7 years born after B19V NAT screening was implemented were tested. Age-specific prevalence rates were generally higher for subjects exposed to either plasma-derived products alone or in combination with other products compared to subjects with no exposure to antihemophilic products. Overall, compared to participants unexposed to blood or blood products, those exposed to plasma-derived products alone were 1.7 times more likely to have antibodies to B19V (p = 0.002). CONCLUSION: These results are consistent with continued B19V transmission through plasma-derived factor concentrates. Effective viral inactivation and detection processes are needed to protect users of these products from infection with B19V or other new or emerging viruses.


Asunto(s)
Factores de Coagulación Sanguínea/efectos adversos , Hemofilia A , Infecciones por Parvoviridae/sangre , Infecciones por Parvoviridae/transmisión , Parvovirus B19 Humano/aislamiento & purificación , Algoritmos , Almacenamiento de Sangre/métodos , Factores de Coagulación Sanguínea/uso terapéutico , Niño , Preescolar , Enfermedades Transmisibles Emergentes/sangre , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/transmisión , ADN Viral/análisis , Femenino , Hemofilia A/sangre , Hemofilia A/tratamiento farmacológico , Hemofilia A/virología , Hemorragia/sangre , Hemorragia/tratamiento farmacológico , Hemorragia/virología , Humanos , Control de Infecciones/métodos , Modelos Logísticos , Masculino , Infecciones por Parvoviridae/epidemiología , Parvovirus B19 Humano/genética , Prevalencia , Estudios Seroepidemiológicos
14.
Res Sq ; 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37886476

RESUMEN

Hemophilia-A (HA) is caused by heterogeneous loss-of-function factor (F)VIII gene (F8)-mutations and deficiencies in plasma-FVIII-activity that impair intrinsic-pathway-mediated coagulation-amplification. The standard-of-care for severe-HA-patients is regular infusions of therapeutic-FVIII-proteins (tFVIIIs) but ~30% develop neutralizing-tFVIII-antibodies called "FVIII-inhibitors (FEIs)" and become refractory. We used the PATH study and ImmunoChip to scan immune-mediated-disease (IMD)-genes for novel and/or replicated genomic-sequence-variations associated with baseline-FEI-status while accounting for non-independence of data due to genetic-relatedness and F8-mutational-heterogeneity. The baseline-FEI-status of 450 North American PATH subjects-206 with black-African-ancestry and 244 with white-European-ancestry-was the dependent variable. The F8-mutation-data and a genetic-relatedness matrix were incorporated into a binary linear-mixed model of genetic association with baseline-FEI-status. We adopted a gene-centric-association-strategy to scan, as candidates, pleiotropic-IMD-genes implicated in the development of either ³2 autoimmune-/autoinflammatory-disorders (AADs) or ³1 AAD and FEIs. Baseline-FEI-status was significantly associated with SNPs assigned to NOS2A (rs117382854; p=3.2E-6) and B3GNT2 (rs10176009; p=5.1E-6), which have functions in anti-microbial-/-tumoral-immunity. Among IMD-genes implicated in FEI-risk previously, we identified strong associations with CTLA4 assigned SNPs (p=2.2E-5). The F8-mutation-effect underlies ~15% of the total heritability for baseline-FEI-status. Additive genetic heritability and SNPs in IMD-genes account for >50% of the patient-specific variability in baseline-FEI-status. Race is a significant determinant independent of F8-mutation-effects and non-F8-genetics.

15.
J Urol ; 188(4 Suppl): 1500-4, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22910268

RESUMEN

PURPOSE: Guidelines for staging Wilms tumor mandate regional lymph node sampling at nephrectomy. However, the usefulness of preoperative computerized tomography in staging lymph nodes has not been rigorously investigated. Thus, we correlated preoperative computerized tomography and pathological lymph node findings to establish a radiological criterion for pathological lymph node enlargement. MATERIALS AND METHODS: We reviewed the medical records of children with Wilms tumor at our institution who underwent pre-chemotherapy surgery with lymph node sampling and had preoperative computerized tomography with contrast medium available for interpretation. Computerized tomography was independently reviewed by 2 radiologists blinded to the pathological findings. We collected data on the diameter of the largest regional lymph node identified and this measurement was correlated with the pathological results. RESULTS: A total of 52 children (25 male, 27 female) with a median age of 3.1 years (range 0.4 to 9.6) were identified. The median largest regional lymph node diameter was 6 mm (range 2 to 15). Of the children 10 (19.2%) had metastatic involvement of sampled lymph nodes. A radiological cutoff of 7 mm for lymph node positivity corresponded to a negative predictive value of 89.0%, a sensitivity of 70.0% and a specificity of 57.1%. A ROC curve was constructed with these data describing the prognostic ability of the diameter of the largest regional lymph node on preoperative computerized tomography to determine lymph node positivity in Wilms tumor, which revealed an AUC of 0.67 (95% CI 0.48-0.87, p = 0.09). CONCLUSIONS: By defining a radiological size cutoff for suspicious lymph nodes, preoperative computerized tomography for staging lymph nodes in Wilms tumor demonstrates potential clinical usefulness through risk stratification for therapy and future study design.


Asunto(s)
Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/patología , Tomografía Computarizada por Rayos X , Tumor de Wilms/diagnóstico por imagen , Tumor de Wilms/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Ganglios Linfáticos/patología , Masculino , Estadificación de Neoplasias , Cuidados Preoperatorios , Estudios Retrospectivos
17.
J Thromb Haemost ; 18(1): 201-216, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31556206

RESUMEN

BACKGROUND: Plasma-derived (pd) or recombinant (r) therapeutic factor VIII proteins (FVIIIs) are infused to arrest/prevent bleeding in patients with hemophilia A (PWHA). However, FVIIIs are neutralized if anti-FVIII-antibodies (inhibitors) develop. Accumulating evidence suggests that pdFVIIIs with von Willebrand factor (VWF) are less immunogenic than rFVIIIs and that distinct rFVIIIs are differentially immunogenic. Since inhibitor development is T-helper-cell-dependent, human leukocyte antigen (HLA)-class-II (HLAcII) molecules constitute an important early determinant. OBJECTIVES: Use dendritic cell (DC)-protein processing/presentation assays with mass-spectrometric and peptide-proteomic analyses to quantify the DP-bound, DQ-bound, and DR-bound FVIII-derived peptides in individual HLAcII repertoires and compare the immunogenic potential of six distinct FVIIIs based on their measured peptide counts. PATIENTS/METHODS: Monocyte-derived DCs from normal donors and/or PWHA were cultured with either: Mix-rFVIII, a VWF-free equimolar mixture of a full-length (FL)-rFVIII [Advate® (Takeda)] and four distinct B-domain-deleted (BDD)-rFVIIIs [Xyntha® (Pfizer), NovoEight® (Novo-Nordisk), Nuwiq® (Octapharma), and Afstyla® (CSL Behring GmBH)]; a pdFVIII + pdVWF [Beriate® (CSL Behring GmBH)]; Advate ± pdVWF; Afstyla ± pdVWF; and Xyntha + pdVWF. RESULTS: We showed that (i) Beriate had a significantly lower immunogenic potential than Advate ± pdVWF, Afstyla - pdVWF, and Mix-rFVIII; (ii) distinct FVIIIs differed significantly in their immunogenic potential in that, in addition to (i), Afstyla + pdVWF had a significantly lower immunogenic potential than Beriate, while the immunogenic potential of Beriate was not significantly different from that of Xyntha + pdVWF; and (iii) rFVIIIs with pdVWF had significantly lower immunogenic potentials than the same rFVIIIs without pdVWF. CONCLUSIONS: Our results provide HLAcII peptidomic level explanations for several important clinical observations/issues including the differential immunogenicity of distinct FVIIIs and the role of HLAcII genetics in inhibitor development.


Asunto(s)
Factor VIII , Hemofilia A , Células Dendríticas , Antígenos HLA , Hemofilia A/tratamiento farmacológico , Humanos , Proteómica
19.
Oecologia ; 81(4): 490-493, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28312642

RESUMEN

In 1985 and 1986, more than 180 adults of Prodoxus y-inversus Riley eclosed from cocoons of the 1969 generation in Yucca baccata, after prepupal larvae spent 16 and 17 years in diapause, intervals prior to mass emergence that are unmatched by any other insect on record. The emergences, which occurred during 15- to 16-day periods, followed many years of virtually no maturation by other individuals of the colony, and the size of the moths was not diminished by the long wait. Successful delay of development and synchronous emergence by many individuals indicates that whole populations can postpone activities through long periods of conditions that would be adverse for adult activity.

20.
Hematology Am Soc Hematol Educ Program ; 2014(1): 355-63, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25696879

RESUMEN

Hemophilia is a genetic disease caused by a deficiency of one of the coagulation proteins. The term usually refers to either hemophilia A, factor VIII (FVIII), with an incidence of ∼1 in 5000 male births, or hemophilia B, factor IX (FIX), with an incidence of ∼1 in 30 000 male births. When severe, the disease leads to spontaneous life-threatening bleeding episodes. Current therapy requires frequent intravenous infusions of therapeutic factor concentrates. Most patients administer the infusions at home every few days and must limit their physical activities to avoid bleeding when the factor activity levels are below normal. In March 2014, a new therapeutic FIX preparation was approved for clinical use in Canada and the United States and, in June 2014, a new FVIII preparation was approved for clinical use in the United States. Over the next couple of years, other new factor products for FIX, FVIIa, and FVIII, which are currently in late stages of clinical trials, will likely also be approved. These new factors have been engineered to extend their half-life in circulation, thus providing major therapeutic advances for patients with hemophilia primarily by allowing treatment with fewer infusions per month. In the clinical trials so far, >500 patients have successfully used these extended half-life products regularly for >1 year to prevent spontaneous bleeding, to treat successfully any bleeding episodes, and to provide effective coagulation for major surgery. Essentially all infusions were well tolerated and effective. These promising new therapies should allow patients to use fewer infusions to maintain appropriate clotting factor activity levels in all clinical settings.


Asunto(s)
Factores de Coagulación Sanguínea/uso terapéutico , Animales , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Semivida , Hemofilia A/tratamiento farmacológico , Humanos , Proteínas Recombinantes de Fusión/uso terapéutico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA