Identification of the amino-acetonitrile derivative monepantel (AAD 1566) as a new anthelmintic drug development candidate

Anthelmintic resistance has become a global phenomenon in gastro-intestinal nematodes of farm animals, including multi-drug resistance against the three major classes of anthelmintics. There is an urgent need for an anthelmintic with a new mode of action. The recently discovered amino-acetonitrile derivatives (AADs) offer a new class of synthetic chemicals with anthelmintic activity. The evaluation of AADs was pursued applying in vitro assays and efficacy and tolerability studies in rodents, sheep, and cattle. Amongst various suitable compounds, AAD 1566 eliminated many tested pathogenic nematode species, both at larval and adult stages, at a dose of 2.5 mg/kg bodyweight in sheep and 5.0 mg/kg bodyweight in cattle. The same doses were sufficient to cure animals infected with resistant or multi-drug-resistant nematode isolates. These findings, complemented by the good tolerability and low toxicity to mammals, suggest that AAD 1566, monepantel, would be a suitable anthelmintic drug development candidate

Elastic domains regulate growth and organogenesis in the plant shoot apical meristem

Although genetic control of morphogenesis is well established, elaboration of complex shapes requires changes in the mechanical properties of cells. In plants, the first visible sign of leaf formation is a bulge on the flank of the shoot apical meristem. Bulging results from local relaxation of cell walls, which causes them to yield to internal hydrostatic pressure. By manipulation of tissue tension in combination with quantitative live imaging and finite-element modeling, we found that the slow-growing area at the shoot tip is substantially strain-stiffened compared with surrounding fast-growing tissue. We propose that strain stiffening limits growth, restricts organ bulging, and contributes to the meristem's functional zonation. Thus, mechanical signals are not just passive readouts of gene action but feed back on morphogenesis

Vaccination with recombinant paramyosin against the bovine lungworm <em>Dictyocaulus viviparus</em> considerably reduces worm burden and larvae shedding.

BACKGROUND: The lungworm Dictyocaulus viviparus, causing parasitic bronchitis in cattle, induces a temporary protective immunity that prevents clinical disease. A radiation-attenuated larvae based vaccine is commercially available in a few European countries, but has the disadvantages of a live vaccine. As a recombinant subunit vaccine would overcome these disadvantages, the parasite&#39;s muscle protein paramyosin (PMY) was tested as a recombinant vaccine antigen. METHODS: D. viviparus-PMY was recombinantly expressed in Escherichia coli as a glutathione-S-transferase (GST)-fused protein. Emulsified in adjuvant Saponin Quil A, the protein was given intramuscularly into calves. Two independent recombinant PMY (rPMY) vaccination trials with negative control groups (first trial: adjuvant only; second trial: non-fused GST) as well as an additional positive control group in the second trial, using the Bovilis(&copy;)Dictol live vaccine to verify vaccination results, were performed. To determine the vaccination success, shedding of larvae as well as worm burden and worm sizes were analyzed. Additionally, ELISA-based determination of development of immunglobulins IgM, IgA, IgE, IgG as well as the subclasses IgG1 and IgG2 was performed. To analyze PMY localization in the bovine lungworm, immunohistochemical staining of adult worms was carried out. RESULTS: Immunohistochemical staining revealed that PMY is part of the bovine lungworm&#39;s pharyngeal and body wall muscles. Vaccination with rPMY resulted in 47% [geometric mean: 67%] and 57% (geometric mean: 71%) reduction of larvae shedding in the first and second vaccination trial, respectively. Worm burden was reduced by 54% (geometric mean: 86%) and 31% (geometric mean: 68%), respectively, and worms of rPMY-vaccinated cattle were significantly shorter in both trials. Furthermore, ELISAs showed a clear antibody response towards rPMY with exception of IgE for which titers could not be detected. After challenge infection, rPMY antibodies were only exceptionally elevated among study animals indicating PMY to be a hidden antigen. CONCLUSIONS: Even though vaccination with the attenuated live vaccine was with 94% (geometric mean: 95%) reduction in larvae shedding and 93% (geometric mean: 94%) reduction in worm burden superior to rPMY vaccination, results using the latter are promising and show the potential for further development of a recombinant PMY-based vaccine against the bovine lungworm

A single EFEMP1 mutation associated with both Malattia Leventinese and Doyne honeycomb retinal dystrophy.

Malattia Leventinese (ML) and Doyne honeycomb retinal dystrophy (DHRD) refer to two autosomal dominant diseases characterized by yellow-white deposits known as drusen that accumulate beneath the retinal pigment epithelium (RPE). Both loci were mapped to chromosome 2p16-21 (refs 5,6) and this genetic interval has been subsequently narrowed. The importance of these diseases is due in large part to their close phenotypic similarity to age-related macular degeneration (AMD), a disorder with a strong genetic component that accounts for approximately 50% of registered blindness in the Western world. Just as in ML and DHRD, the early hallmark of AMD is the presence of drusen. Here we use a combination of positional and candidate gene methods to identify a single non-conservative mutation (Arg345Trp) in the gene EFEMP1 (for EGF-containing fibrillin-like extracellular matrix protein 1) in all families studied. This change was not present in 477 control individuals or in 494 patients with age-related macular degeneration. Identification of this mutation may aid in the development of an animal model for drusen, as well as in the identification of other genes involved in human macular degeneration

Methylation silencing and mutations of the p14ARF and p16INK4a genes in colon cancer.

The INK4a-ARF locus encodes two tumor suppressor proteins involved in cell-cycle regulation, p16INK4a and p14ARF, whose functions are inactivated in many human cancers. The aim of this study was to evaluate p14ARF and p16INK4a gene inactivation and its association with some clinocopathological parameters in colon cancer. The mutational and methylation status of the p14ARF and p16INK4a genes was analyzed in 60 primary colon carcinomas and 8 colon cancer cell lines. We have identified the first two reported mutations affecting exon 1beta of p14ARF in the HCT116 cell line and in one of the primary colon carcinomas. Both mutations occur within the N-terminal region of p14ARF, documented as important for nucleolar localization and interaction with Mdm2. Tumor-specific methylation of the p14ARF and p16INK4a genes was found in 33% and 32% of primary colon carcinomas, respectively. Methylation of the p14ARF was inversely correlated with p53 overexpression (p = 0.02). p14ARF and p16INK4a gene methylation was significantly more frequent in right-sided than in left-sided tumors (p = 0.02). Methylation of the p14ARF gene occurred more frequently in well-differentiated adenocarcinomas (p = 0.005), whereas the p16INK4a gene was more often methylated in poorly differentiated adenocarcinomas (p = 0.002). The present results underline the role of p14ARF and p16INK4a gene inactivation in the development of colon carcinoma. They suggest that the methylation profile of specific genes, in particular p14ARF and p16INK4a, might be related to biologically distinct subsets of colon carcinomas and possibly to different tumorigenic pathways