Direct carrier detection by in situ suppression hybridization with cosmid clones of the Duchenne/Becker muscular dystrophy locus

A basic problem in genetic counseling of families with Duchenne/Becker muscular dystrophy (DMD/BMD) concerns the carrier status of female relatives of an affected male. In about 60% of these patients, deletions of one or more exons of the dystrophin gene can be identified. These deletions preferentially include exon 45, which can be detected by multiplex polymerase chain reaction (PCR) and Southern blot analysis of genomic cosmid clones that map to this critical region. As a new approach for definitive carrier detection, we have performed chromosomal in situ suppression (CISS) hybridization with these cosmid clones in female relatives of four unrelated patients. In normal females, most metaphases showed signals on both×chromosomes, whereas only one×chromosome was labeled in carriers. Our results demonstrate that CISS hybridization can define the carrier status in female relatives of DMD patients exhibiting a deletion in the dystrophin gene

A strategy for the characterization of minute chromosome rearrangements using multiple color fluorescence in situ hybridization with chromosome-specific DNA libraries and YAC clones

The identification of marker chromosomes in clinical and tumor cytogenetics by chromosome banding analysis can create problems. In this study, we present a strategy to define minute chromosomal rearrangements by multicolor fluorescence in situ hybridization (FISH) with whole chromosome painting probes derived from chromosome-specific DNA libraries and Alu-polymerase chain reaction (PCR) products of various region-specific yeast artificial chromosome (YAC) clones. To demonstrate the usefulness of this strategy for the characterization of chromosome rearrangements unidentifiable by banding techniques, an 8p+ marker chromosome with two extra bands present in the karyotype of a child with multiple anomalies, malformations, and severe mental retardation was investigated. A series of seven-color FISH experiments with sets of fluorochrome-labeled DNA library probes from flow-sorted chromosomes demonstrated that the additional segment on 8p+ was derived from chromosome 6. For a more detailed characterization of the marker chromosome, three-color FISH experiments with library probes specific to chromosomes 6 and 8 were performed in combination with newly established telomeric and subtelomeric YAC clones from 6q25, 6p23, and 8p23. These experiments demonstrated a trisomy 6pter6p22 and a monosomy 8pter8p23 in the patient. The present limitations for a broad application of this strategy and its possible improvements are discusse

Space Shuttle orbiter entry heating and TPS response: STS-1 predictions and flight data

Aerothermodynamic development flight test data from the first orbital flight test of the Space Transportation System (STS) transmitted after entry blackout is given. Engineering predictions of boundary layer transition and numerical simulations of the orbiter flow field were confirmed. The data tended to substantiate preflight predictions of surface catalysis phenomena. The thermal response of the thermal protection system was as expected. The only exception is that internal free convection was found to be significant in limiting the peak temperature of the structure in areas which do not have internal insulation

Pulses of Notch activation synchronise oscillating somite cells and entrain the zebrafish segmentation clock

Formation of somites, the rudiments of vertebrate body segments, is an oscillatory process governed by a gene-expression oscillator, the segmentation clock. This operates in each cell of the presomitic mesoderm (PSM), but the individual cells drift out of synchrony when Delta/Notch signalling fails, causing gross anatomical defects. We and others have suggested that this is because synchrony is maintained by pulses of Notch activation, delivered cyclically by each cell to its neighbours, that serve to adjust or reset the phase of the intracellular oscillator. This, however, has never been proved. Here, we provide direct experimental evidence, using zebrafish containing a heat-shock-driven transgene that lets us deliver artificial pulses of expression of the Notch ligand DeltaC. In DeltaC-defective embryos, in which endogenous Notch signalling fails, the artificial pulses restore synchrony, thereby rescuing somite formation. The spacing of segment boundaries produced by repetitive heat-shocking varies according to the time interval between one heat-shock and the next. The induced synchrony is manifest both morphologically and at the level of the oscillations of her1, a core component of the intracellular oscillator. Thus, entrainment of intracellular clocks by periodic activation of the Notch pathway is indeed the mechanism maintaining cell synchrony during somitogenesis

A Systematic Review and Metaanalysis on the Effects of Garlic Preparations on Blood Pressure in Individuals With Hypertension

BACKGROUND Many patients prefer herbal medications to conventional drugs. Limited trial evidence suggests that garlic preparations reduce high blood pressure (BP). METHODS We searched electronic databases through March 2014 to identify all randomized controlled trials that compared a garlic preparation to placebo in hypertensive patients. Trials were required to report BP values at baseline and after a follow-up of at least 4 weeks. RESULTS Nine double-blind trials with 482 individuals fulfilled our inclusion criteria. Included trials were rather small, and the quality of the majority of included trials was moderate. Follow-up ranged from 8 to 26 weeks. All trials reported office BP measurements. Systolic BP and diastolic BP (SBP and DBP) were more effectively reduced in individuals treated with garlic preparations than in individuals treated with placebo. However, heterogeneity was high (weighted mean difference (WMD) for SBP was −9.1mm Hg; 95% confidence interval (CI), −12.7 to −5.4; P for heterogeneity = 0.0006; and I 2 = 71%; WMD for BP was −3.8mm Hg; 95% CI, −6.7 to −1.0; P for heterogeneity = 0.00001; I 2 = 80%). When analyses were restricted to higher-quality trials using intention-to-treat analysis or to trials with concealed treatment allocation and standardized and blinded BP measurement, effect sizes for SBP but not for DBP were lower and heterogeneity disappeared. CONCLUSIONS Although evidence from this review suggests that garlic preparations may lower BP in hypertensive individuals, the evidence is not strong. A well-conducted and powered trial of longer duration is needed to confirm these finding

Evaluating annotations of an Agilent expression chip suggests that many features cannot be interpreted

<p>Abstract</p> <p>Background</p> <p>While attempting to reanalyze published data from Agilent 4 × 44 human expression chips, we found that some of the 60-mer olignucleotide features could not be interpreted as representing single human genes. For example, some of the oligonucleotides align with the transcripts of more than one gene. We decided to check the annotations for all autosomes and the X chromosome systematically using bioinformatics methods.</p> <p>Results</p> <p>Out of 42683 reporters, we found that 25505 (60%) passed all our tests and are considered "fully valid". 9964 (23%) reporters did not have a meaningful identifier, mapped to the wrong chromosome, or did not pass basic alignment tests preventing us from correlating the expression values of these reporters with a unique annotated human gene. The remaining 7214 (17%) reporters could be associated with either a unique gene or a unique intergenic location, but could not be mapped to a transcript in RefSeq. The 7214 reporters are further partitioned into three different levels of validity.</p> <p>Conclusion</p> <p>Expression array studies should evaluate the annotations of reporters and remove those reporters that have suspect annotations. This evaluation can be done systematically and semi-automatically, but one must recognize that data sources are frequently updated leading to slightly changing validation results over time.</p