7 research outputs found
Sequential SDF1a and b-induced mobility guides Medaka PGC migration
AbstractAssembly and formation of the gonad primordium are the first steps toward gonad differentiation and subsequent sex differentiation. Primordial germ cells (PGCs) give rise to the gametes that are responsible for the development of a new organism in the next generation. In many organisms, following their specification the germ cells migrate toward the location of the prospective gonadal primordium. To accomplish this, the PGCs obtain directional cues from cells positioned along their migration path. One such cue, the chemokine SDF1 (stromal cell-derived factor 1) and its receptor CXCR4 have recently been found to be critical for proper PGC migration in zebrafish, chick and mouse.We have studied the mechanisms responsible for PGC migration in Medaka. In contrast to the situation observed in zebrafish, where proper PGC positioning is the result of active migration in the direction of the source of SDF1a, Medaka PGC movements are shown to be the consequence of a combination of active SDF1a and SDF1b-guided migration. In this process both SDF1 co-orthologues show only partly overlapping expression pattern and cooperate in the correct positioning of the PGCs
Randomized controlled phase 2 trial of hydroxychloroquine in childhood interstitial lung disease
Background
No results of controlled trials are available for any of the few treatments offered to children with interstitial lung diseases (chILD). We evaluated hydroxychloroquine (HCQ) in a phase 2, prospective, multicentre, 1:1-randomized, double-blind, placebo-controlled, parallel-group/crossover trial. HCQ (START arm) or placebo were given for 4 weeks. Then all subjects received HCQ for another 4 weeks. In the STOP arm subjects already taking HCQ were randomized to 12 weeks of HCQ or placebo (= withdrawal of HCQ). Then all subjects stopped treatment and were observed for another 12 weeks.
Results
26 subjects were included in the START arm, 9 in the STOP arm, of these four subjects participated in both arms. The primary endpoint, presence or absence of a response to treatment, assessed as oxygenation (calculated from a change in transcutaneous O 2 -saturation of ≥ 5%, respiratory rate ≥ 20% or level of respiratory support), did not differ between placebo and HCQ groups. Secondary endpoints including change of O 2 -saturation ≥ 3%, health related quality of life, pulmonary function and 6-min-walk-test distance, were not different between groups. Finally combining all placebo and all HCQ treatment periods did not identify significant treatment effects. Overall effect sizes were small. HCQ was well tolerated, adverse events were not different between placebo and HCQ.
Conclusions
Acknowledging important shortcomings of the study, including a small study population, the treatment duration, lack of outcomes like lung function testing below age of 6 years, the small effect size of HCQ treatment observed requires careful reassessments of prescriptions in everyday practice (EudraCT-Nr.: 2013-003714-40, www.clinicaltrialsregister.eu , registered 02.07.2013)
Terminal chromosome 4q deletion syndrome in an infant with hearing impairment and moderate syndromic features: review of literature
Background
Terminal deletions of chromosome 4q are associated with a broad spectrum of phenotypes including cardiac, craniofacial, digital, and cognitive impairment. The rarity of this syndrome renders genotype-phenotype correlation difficult, which is further complicated by the widely different phenotypes observed in patients sharing similar deletion intervals.
Case presentation
Herein, we describe a boy with congenital hearing impairment and a variety of moderate syndromic features that prompted SNP array analysis disclosing a heterozygous 6.9 Mb deletion in the 4q35.1q35.2 region, which emerged de novo in the maternal germ line.
Conclusion
In addition to the index patient, we review 35 cases from the literature and DECIPHER database to attempt genotype-phenotype correlations for a syndrome with great phenotypic variability. We delineate intervals with recurrent phenotypic overlap, particularly for cleft palate, congenital heart defect, intellectual disability, and autism spectrum disorder. Broad phenotypic presentation of the terminal 4q deletion syndrome is consistent with incomplete penetrance of the individual symptoms