Longitudinal MRI brain volume changes over one year in children with mucopolysaccharidosis types IIIA and IIIB

ObjectiveTo quantify changes in segmented brain volumes over 12 months in children with mucopolysaccharidosis types IIIA and IIIB (MPS IIIA and IIIB).MethodsIn order to establish suitable outcome measures for clinical trials, twenty-five children greater than 2 years of age were enrolled in a prospective natural history study of MPS IIIA and IIIB at Nationwide Children's Hospital. Data from sedated non-contrast brain 3 T MRIs and neuropsychological measures were reviewed from the baseline visit and at 12-month follow-up. No intervention beyond standard clinical care was provided. Age- and sex-matched controls were gathered from the National Institute of Mental Health Data Archive. Automated brain volume segmentation with longitudinal processing was performed using FreeSurfer.ResultsOf the 25 subjects enrolled with MPS III, 17 children (4 females, 13 males) completed at least one MRI with interpretable volumetric data. The ages ranged from 2.8 to 13.7 years old (average 7.2 years old) at enrollment, including 8 with MPS IIIA and 9 with MPS IIIB. At baseline, individuals with MPS III demonstrated reduced cerebral white matter and corpus callosum volumes, but greater volumes of the lateral ventricles, cerebellar cortex, and cerebellar white matter compared to controls. Among the 13 individuals with MPS III with two interpretable MRIs, there were annualized losses or plateaus in supratentorial brain tissue volumes (cerebral cortex ?42.10 ± 18.52 cm³/year [mean ± SD], cerebral white matter ?4.37 ± 11.82 cm³/year, subcortical gray matter ?6.54 ± 3.63 cm³/year, corpus callosum ?0.18 ± 0.62 cm³/yr) and in cerebellar cortex (?0.49 ± 12.57 cm³/year), with a compensatory increase in lateral ventricular volume (7.17 ± 6.79 cm³/year). Reductions in the cerebral cortex and subcortical gray matter were more striking in individuals younger than 8 years of age. Greater cerebral cortex volume was associated with higher fine and gross motor functioning on the Mullen Scales of Early Learning, while greater subcortical gray matter volume was associated with higher nonverbal functioning on the Leiter International Performance Scale. Larger cerebellar cortex was associated with higher receptive language performance on the Mullen, but greater cerebellar white matter correlated with worse adaptive functioning on the Vineland Adaptive Behavioral Scales and visual problem-solving on the Mullen.ConclusionsLoss or plateauing of supratentorial brain tissue volumes may serve as longitudinal biomarkers of MPS III age-related disease progression compared to age-related growth in typically developing controls. Abnormally increased cerebellar white matter in MPS III, and its association with worse performance on neuropsychological measures, suggest the possibility of pathophysiological mechanisms distinct from neurodegeneration-associated atrophy that warrant further investigation.     

Genetic Abnormalities in FOXP1 Are Associated with Congenital Heart Defects

The etiology for the majority of congenital heart defects (CHD) is unknown. We identified a patient with unbalanced atrioventricular septal defect (AVSD) and hypoplastic left ventricle who harbored an ～0.3 Mb monoallelic deletion on chromosome 3p14.1. The deletion encompassed the first four exons of FOXP1, a gene critical for normal heart development that represses cardiomyocyte proliferation and expression of Nkx2.5. To determine whether FOXP1 mutations are found in patients with CHD, we sequenced FOXP1 in 82 patients with AVSD or hypoplastic left heart syndrome. We discovered two patients who harbored a heterozygous c.1702C>T variant in FOXP1 that predicted a potentially deleterious substitution of a highly conserved proline (p.Pro568Ser). This variant was not found in 287 controls but is present in dbSNP at a 0.2% frequency. The orthologous murine Foxp1 p.Pro596Ser mutant protein displayed deficits in luciferase reporter assays and resulted in increased proliferation and Nkx2.5 expression in cardiomyoblasts. Our data suggest that haploinsufficiency of FOXP1 is associated with human CHD.     

Current management of patients hospitalized with complicated skin and soft tissue infections across Europe (2010–2011): assessment of clinical practice patterns and real-life effectiveness of antibiotics from the REACH study

Complicated skin and soft tissue infections (cSSTI) are common and frequently require treatment in hospital. Comprehensive current data on management practices in patients hospitalized with cSSTI are limited. REACH was a retrospective, observational cohort study designed to provide data on current clinical management of moderate to severe cSSTI in European hospitals. Data were collected via an electronic case report form from 129 sites in ten European countries. The study population comprised patients ≥18 years, hospitalized between March 2010 and February 2011 with cSSTI who received intravenous antibiotic treatment. Presented here is an analysis of the disease characteristics, treatment patterns during hospitalization and clinical outcomes identified by the study. The total population included 1995 patients (mean age 60.6 years; 57.7% male). Initial antibiotic treatment modification was reported in 39.6% (n = 791) of patients; it was more common in patients with co-morbidities (42.6%), those requiring surgical intervention (43.4%), those with more severe infections such as bacteraemia (51.6%) or with fascia affected (49.0%), those admitted to the intensive care unit (56.2%) and those with lesions > 50 cm² (44.3%). A switch to narrower-spectrum antibiotic treatment (streamlining) occurred in 5.6% of patients. Mean length of hospital stay was 18.5 days (±19.9; median 12.0) and the total mortality rate was 3.4%. The data collected in REACH give a comprehensive and current view of real-life clinical management of cSSTI in European hospitals and provide evidence of a high rate of initial antibiotic treatment modification.     

Juxtaposition of the T-cell receptor alpha-chain locus (14q11) and a region (14q32) of potential importance in leukemogenesis by a 14;14 translocation in a patient with T-cell chronic lymphocytic leukemia and ataxia-telangiectasia.

We describe a t(14;14)(q11;q32) translocation in a patient with T-cell chronic lymphocytic leukemia and ataxia-telangiectasia (AT). By using a battery of joining (J)-segment probes from the T-cell receptor (TCR) alpha-chain locus TCRA, three distinct J alpha rearrangements were observed. One rearrangement reflected a normal TCRA variable (V) region V alpha-to-J alpha recombination. The second rearrangement was caused by the translocation even itself, which joined a DNA segment from 14q32 centromeric to the immunoglobulin heavy chain locus (IGH) and a J alpha gene located approximately 75 kilobases (kb) 5' of the TCRA constant region gene (C alpha). A third rearrangement involved a 17-kb internal deletion 3' to the translocation, a rearrangement within the J alpha locus that has been observed once before in a patient with AT. Analysis of these three rearrangements underscores the increase in aberrant locus-specific recombination in lymphocytes from patients with AT. Furthermore, these studies support the view that a growth-effecting gene is present in the 14q32 region that participates in the leukemogenic process.     

Immunohistochemical localization of membrane and alpha-granule proteins in human megakaryocytes: application to plastic-embedded bone marrow biopsy specimens

Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes.     

Antiarrhythmic drug therapy and cardiac mortality in atrial fibrillation. The Stroke Prevention in Atrial Fibrillation Investigators.

BACKGROUND AND OBJECTIVES. The relation between cardiac mortality and antiarrhythmic drug administration has not been fully determined. This relation was analyzed in 1,330 patients enrolled in the Stroke Prevention in Atrial Fibrillation Study, a randomized clinical trial comparing warfarin, aspirin and placebo for the prevention of ischemic stroke or systemic embolism in patients with nonvalvular atrial fibrillation. METHODS. Patients who received antiarrhythmic drug therapy for atrial fibrillation in this study were compared with patients not receiving antiarrhythmic agents. The relative risk of cardiac mortality, including arrhythmic death, in patients receiving antiarrhythmic drug therapy was determined and adjusted for other cardiac risk factors. RESULTS. In patients receiving antiarrhythmic drug therapy, cardiac mortality was increased 2.5-fold (p = 0.006, 95% confidence interval [CI] 1.3 to 4.9) and arrhythmic death was increased 2.6-fold (p = 0.02, 95% CI 1.2 to 5.6). Among patients with a history of congestive heart failure, those given antiarrhythmic medications had a relative risk of cardiac death of 4.7 (p less than 0.001, 95% CI 1.9 to 11.6) compared with that of patients not so treated; the relative risk of arrhythmic death in the treated group was 3.7 (p = 0.01, 95% CI 1.3 to 10.4). Patients without a history of congestive heart failure had no increased risk of cardiac mortality (relative risk 0.70, 95% CI 0.2 to 3.1) during antiarrhythmic drug therapy. After exclusion of 23 patients with documented ventricular arrhythmias and adjustment for other variables predictive of cardiac death, patients receiving antiarrhythmic drugs were not at increased risk of cardiac death or arrhythmic death. However, in patients with a history of heart failure who received antiarrhythmic drug therapy, the relative risk of cardiac death was 3.3 (p = 0.05, 95% CI 0.99 to 11.1) and that of arrhythmic death was 5.8 (p = 0.009, 95% CI 1.5 to 21.7) compared with the risk in patients not taking antiarrhythmic medications. CONCLUSIONS. Although antiarrhythmic drug therapy was not randomly determined in this trial, the data suggest that in patients with atrial fibrillation and a history of congestive heart failure, the risk of such therapy may outweigh the potential benefit of maintaining sinus rhythm.