Genome-wide association and epidemiological analyses reveal common genetic origins between uterine leiomyomata and endometriosis.

Uterine leiomyomata (UL) are the most common neoplasms of the female reproductive tract and primary cause for hysterectomy, leading to considerable morbidity and high economic burden. Here we conduct a GWAS meta-analysis in 35,474 cases and 267,505 female controls of European ancestry, identifying eight novel genome-wide significant (P < 5 × 10-8) loci, in addition to confirming 21 previously reported loci, including multiple independent signals at 10 loci. Phenotypic stratification of UL by heavy menstrual bleeding in 3409 cases and 199,171 female controls reveals genome-wide significant associations at three of the 29 UL loci: 5p15.33 (TERT), 5q35.2 (FGFR4) and 11q22.3 (ATM). Four loci identified in the meta-analysis are also associated with endometriosis risk; an epidemiological meta-analysis across 402,868 women suggests at least a doubling of risk for UL diagnosis among those with a history of endometriosis. These findings increase our understanding of genetic contribution and biology underlying UL development, and suggest overlapping genetic origins with endometriosis.

Phenotypic and Haplotype Diversity among Tetraploid and Hexaploid Wheat Accessions with Potentially Novel Insect Resistance Genes for Wheat Stem Sawfly.

Genetic diversity in breeding programs can be impaired by fixation of alleles derived from a limited number of founder lines. This is demonstrated with the use of a solid-stem trait derived from the Portuguese landrace 'S-615' over 70 yrs ago that is widely used to resist the wheat stem sawfly ( Norton, WSS) in North America. The objective of this study was to evaluate haplotype diversity underlying the quantitative trait locus (QTL) that controls the majority of the S-615 derived solid-stem genetic variation using single-nucleotide polymorphism (SNP) assays in a diverse set of 228 solid-stem tetraploid and hexaploid wheat accessions originating from areas of the world infested with various species of WSS. Haplotype analysis showed all WSS-resistant hexaploid wheat varieties in North America, except 'Conan', evaluated in this study contain a haplotype associated with the S-615 solid-stem allele. In total, 26 haplotypes were identified among the hexaploid and tetraploid accessions at . Prevalence of most haplotypes were skewed toward either the hexaploid or tetraploid wheat accessions. The haplotype found in the S-615- hexaploid wheat landrace was not found in the solid-stem tetraploid landrace accessions evaluated in this study. Haplotype analysis revealed several new haplotypes that have potential to contain novel alleles for solid-stems at , which may form the basis for introducing genetic diversity into breeding programs aimed at WSS resistance.

CD40 ligand, Bcl-2, and Bcl-xL spare group I Burkitt lymphoma cells from CD77-directed killing via Verotoxin-1 B chain but fail to protect against the holotoxin.

Owing to its lineage and differentiation stage-restricted expression, CD77 has been mooted as a therapeutic target in Burkitt lymphoma (BL). The recognition that the globotriaosyl moiety of this neutral glycosphingolipid is a receptor for Escherichia coli-derived Verotoxin-1 (Shiga-Like Toxin-1) offers a potential delivery system for the attack. Here we show that CD77-expressing Group I BL cells which are normally susceptible to activation-induced death on binding Verotoxin-1 B chain are protected in the presence of CD40 ligand. Ectopic expression of either bcl-2 or bcl-xL also afforded resistance to the actions of the B chain. In total contrast, neither of the survival genes nor a CD40 signal - even when acting in concert - protected against killing mediated by the holotoxin. These findings indicate that while therapeutic modalities for CD77-expressing B cell tumors (which include follicular lymphoma) based on the use of Verotoxin-1 B chain might be compromised by the activation of endogenous or exogenous survival pathways, those exploiting the holotoxin should be left unscathed.

Stable, low-loss optical waveguides and micromirrors fabricated in acrylate polymers.

Acrylate-based optical waveguides have been fabricated with optical loss of 0.5 dB/cm at 1300 nm by means of a new material system that ensures stable optical and mechanical properties over a wide temperature range. No increase in loss was measured after 500 h at temperatures up to 150 degrees C, and there was no significant increase in loss during short (<5 min) temperature excursions to 300 degrees C for bonding. Single-mode waveguides were fabricated with refractive indices for core and clad of 1.505 and 1.500, respectively, so that the mode field is very similar to that of single-mode silica fiber. Guides were fabricated on both planar and structured substrates of Si and GaAs as well as on substrates coated with metals and dielectrics. Fabrication involved spin coating and UV exposure to cross-link the polymer, but the substrate temperature did not exceed 180 degrees C. With this method guides could be fabricated on a range of substrates up to 125 cm in diameter, including those with multilayer metallization for multichip modules, providing optical interconnect capability. Microprism reflecting surfaces were fabricated in the waveguides to couple light out normal to the substrate. All the processing was compatible with normal semiconductor fabrication.

Participation of the N-terminal region of Cepsilon3 in the binding of human IgE to its high-affinity receptor FcepsilonRI.

The binding of immunoglobulin E (IgE) to its high-affinity receptor (FcepsilonRI) expressed on mast cells and basophils is central to the development of an allergic reaction. Previous studies have implicated the third constant domain of IgE-Fc (Cepsilon3) as the site of the interaction with FcepsilonRI. We have prepared a series of site-directed mutants of human IgE-Fc, particularly focusing on the N-terminal "linker" region and AB loop of Cepsilon3. The kinetics of binding IgE and its Fc fragments to the immobilized receptor were determined by surface plasmon resonance (SPR), and two phases of binding were observed. We identified one mutation in the N-terminal linker region, R334S, that has a dramatic effect on binding. R334S lowers the affinity of IgE-Fc for FcepsilonRI by 120-fold, principally through an increase in the dissociation rate of the slower phase of the interaction. This mutation has a similar effect in Fcepsilon3-4, a truncated form of IgE-Fc which lacks the Cepsilon2 domain pair, and thus it does not exert its effect through altering the quaternary structure of IgE-Fc, firmly implicating Arg334 as a contact residue in the complex. However R334S has no effect on the binding of FcepsilonRII (CD23), the low-affinity receptor for IgE, demonstrating the structural integrity of the mutated IgE-Fc. Circular dichroism spectroscopy and thermal stability studies further indicate that the R334S mutation does not disorder or destabilize the structure of IgE-Fc or Fcepsilon3-4. These results demonstrate the importance of the N-terminal linker region of Cepsilon3 in the interaction of IgE with FcepsilonRI.

Identification of contact residues in the IgE binding site of human FcepsilonRIalpha.

The high-affinity receptor for immunoglobulin E (IgE), FcepsilonRI, is an alphabetagamma2 tetramer found on mast cells, basophils, and several other types of immune effector cells. The interaction of IgE with the alpha-subunit of FcepsilonRI is central to the pathogenesis of allergy. Detailed knowledge of the mode of interaction of FcepsilonRI with IgE may facilitate the development of inhibitors for general use in the treatment of allergic disease. To this end we have performed site-directed mutagenesis on a soluble form of the FcepsilonRI alpha-chain (sFcepsilonRIalpha). The effects of four mutations in the second immunoglobulin-like domain of sFcepsilonRIalpha upon the kinetics of binding to IgE and fragments of IgE have been analyzed using surface plasmon resonance. As described in the preceding paper of this issue [Henry, A. J., et al. (1997) Biochemistry 36, 15568-15578], biphasic binding kinetics was observed. Two of the mutations had significant effects on binding: K117D reduced the affinity of sFcepsilonRIalpha for IgE by a factor of 30, while D159K increased the affinity for IgE by a factor of 7, both principally through changes in the rates of dissociation of the slower phase of the interaction. Circular dichroism spectra of sFcepsilonRIalpha incorporating either of these mutations were indistinguishable from those of wild-type sFcepsilonRIalpha, demonstrating that the native conformation had not been disrupted. Our results, together with those from site-directed mutagenesis on fragments of IgE presented in the accompanying paper, define the contact surfaces in the IgE:sFcepsilonRIalpha complex.

Biologically active interleukin 2-ricin A chain fusion proteins may require intracellular proteolytic cleavage to exhibit a cytotoxic effect.

DNA fusions encoding chimeric proteins in which human interleukin 2 (IL2) was fused to the A subunit of the plant cytotoxin ricin (RA) have been expressed in Xenopus oocytes. The constructs contained N-terminal IL2 and C-terminal RA, or N-terminal RA and C-terminal IL2. In the expressed chimeric proteins, the IL2 and RA moieties were joined by a peptide sequence containing a proteolytic cleavage site. Two proteolytically-sensitive peptide sequences were utilized; a peptide that forms the trypsin-sensitive disulfide-bonded loop in diphtheria toxin (DT) or a synthetic peptide containing the factor Xa recognition site in a sequence flanked by two cysteine residues. In an in vitro cell free system the RA component was biologically active in all chimeric proteins produced since it specifically depurinated 28S ribosomal RNA. Proteolytic cleavage of the chimeras with either trypsin or factor Xa as appropriate separated the IL2 and RA moieties, but they did not remain covalently linked by a disulfide bond. Because of this, the cytotoxicity of protease-treated chimeras could not be assessed. Chimeras not pretreated with factor Xa but which contained the factor Xa target sequence were not cytotoxic to CTLL-2 cells. Rather, these molecules had a stimulatory effect that was ascribed to the IL2 moiety. In contrast, recombinant chimeric toxins containing the DT loop sequence were cytotoxic to CTLL-2 cells. Taken together the data suggest that RA-containing chimeras require intracellular proteolytic cleavage to release the RA moiety to render them cytotoxic to target cells.

The shortened advanced course for Army physicians.

The Army uses a series of career courses to prepare officers for progressive assignments. These courses have not been widely utilized by Army physicians. To improve the military education of physicians, an abbreviated Advanced Course was developed by the Academy of Health Science. A study of this course by the physicians attending its first offering showed that 8 weeks was an appropriate length. Information is provided to help improve the course and encourage attendance by Army physicians. This course will likely become mandatory and will be a key element in the training of all Army physicians.

The molecular basis of inhibitor resistance in a mammalian mitochondrial cytochrome b mutant.

The mitochondrial gene for the cytochrome b of Complex III has been cloned from a mouse L-cell mutant with increased resistance to 2-n-heptyl-4-hydroxyquinoline-N-oxide and other inhibitors which block reactions at the b562 heme group. Nucleotide sequencing revealed that this gene contained a G:A transition on the coding strand at position 14,830. At the amino acid level, this mutation results in the substitution of an aspartic acid residue for a conserved glycine at position 231 of cytochrome b. Based upon current models for the secondary structure of cytochrome b, the altered amino acid lies in close proximity to one of the invariant histidine residues involved in binding the heme groups. Combining this result with the previous biochemical studies of this mutant, we hypothesize that the insertion of this highly charged side chain alters the conformation around the b562 heme group such that 2-n-heptyl-4-hydroxyquinoline-N-oxide and the other inhibitors of this group have reduced access to the inhibitor binding domain.

Changing demography of trisomy 18.

The incidence of trisomy 18 in Leicestershire during the years 1980-85 inclusive was one in 3086 births. Eleven of the 21 babies born with trisomy 18 in this period were delivered by caesarean section. Median and mean periods of survival were 2.5 and 22 days, respectively.