Homozygosity for a missense variant in COMP gene associated with severe pseudoachondroplasia.

The phenotypic spectrum associated with heterozygous mutations in cartilage oligomeric matrix protein gene (COMP) range from a mild form of multiple epiphyseal dysplasia (MED) to pseudoachondroplasia (PSACH). However, the phenotypic effect from biallelic COMP variants is unclear. We investigated a large consanguineous Pakistani family with a severe form of PSACH in 2 individuals. Another 14 family members presented with a mild PSACH phenotype similar to MED. Using exome sequencing and subsequent segregation analysis, we identified homozygosity for a COMP missense variant [c.1423G>A; p.(D475N)] in the 2 severely affected individuals, whereas family members with the mild PSACH phenotype were heterozygous. Our observations show for the first time that a biallelic COMP variant may be associated with pronounced and widespread skeletal malformations suggesting an additive effect of the 2 mutated alleles.

Simulating dissolved organic carbon dynamics at the swedish integrated monitoring sites with the integrated catchments model for carbon, INCA-C.

Surface water concentrations of dissolved organic carbon ([DOC]) are changing throughout the northern hemisphere due to changes in climate, land use and acid deposition. However, the relative importance of these drivers is unclear. Here, we use the Integrated Catchments model for Carbon (INCA-C) to simulate long-term (1996-2008) streamwater [DOC] at the four Swedish integrated monitoring (IM) sites. These are unmanaged headwater catchments with old-growth forests and no major changes in land use. Daily, seasonal and long-term variations in streamwater [DOC] driven by runoff, seasonal temperature and atmospheric sulfate (SO4(2-)) deposition were observed at all sites. Using INCA-C, it was possible to reproduce observed patterns of variability in streamwater [DOC] at the four IM sites. Runoff was found to be the main short-term control on [DOC]. Seasonal patterns in [DOC] were controlled primarily by soil temperature. Measured SO4(2-) deposition explained some of the long-term [DOC] variability at all sites.

Experimental methods and modeling techniques for description of cell population heterogeneity.

With the continuous development, in the last decades, of analytical techniques providing complex information at single cell level, the study of cell heterogeneity has been the focus of several research projects within analytical biotechnology. Nonetheless, the complex interplay between environmental changes and cellular responses is yet not fully understood, and the integration of this new knowledge into the strategies for design, operation and control of bioprocesses is far from being an established reality. Indeed, the impact of cell heterogeneity on productivity of large scale cultivations is acknowledged but seldom accounted for. In order to include population heterogeneity mechanisms in the development of novel bioprocess control strategies, a reliable mathematical description of such phenomena has to be developed. With this review, we search to summarize the potential of currently available methods for monitoring cell population heterogeneity as well as model frameworks suitable for describing dynamic heterogeneous cell populations. We will furthermore underline the highly important coordination between experimental and modeling efforts necessary to attain a reliable quantitative description of cell heterogeneity, which is a necessity if such models are to contribute to the development of improved control of bioprocesses.

Insights into the potential functionality of single-chain force-induced conformational transitions in polymer networks: implications for polysaccharide signaling in the plant cell wall.

The behavior of biopolymer networks comprised of clickable polysaccharide chains that can undergo force-induced conformational transitions was investigated during straining using a simulation technique. The simulation was carried out both using an affine deformation field and alternatively using Lees-Edwards boundary conditions as an example of a nonaffine case. In the affine situation the simulated stress-strain curves were found to be consistent with results obtained by evaluating the molecular force-extension curve at a single average extension and calculating the bulk modulus as an average over all possible orientations with respect to the deformation. While in all cases examined the macroscopic mechanical responses of networks of randomly oriented chains, consisting either of simple extensible wormlike chains or their clickable analogs, were found to be indistinguishable, the simulation additionally allowed the number of chains containing sugar rings in different conformational states to be monitored, and this was found to change significantly during straining. This supports the hypothesis that in networks of randomly oriented clickable polysaccharide chains, such conformational transitions could have biological significance as stress switches in signaling processes but that they are unlikely to affect the bulk rheological properties of tissue.

Selectively desulfated heparin inhibits fibroblast growth factor-induced mitogenicity and angiogenesis.

Fibroblast growth factors (FGFs) are known to induce formation of new blood vessels, angiogenesis. We show that FGF-induced angiogenesis can be modulated using selectively desulfated heparin. Chinese hamster ovary cells (CHO677) deficient in heparan sulfate biosynthesis were employed to assess the function of heparin/heparan sulfate in FGF receptor-1 (FGFR-1) signal transduction and biological responses. In the presence of FGF-2, FGFR-1 kinase and subsequent mitogen-activated protein kinase Erk2 activities were augmented in a dose-dependent manner, whereas high concentrations of heparin resulted in decreased activity. The length of the heparin oligomer, minimally an 8/10-mer, was critical for the ability to enhance FGFR-1 kinase activity. The N- and 2-O-sulfate groups of heparin were essential for binding to FGF-2, whereas stimulation of FGFR-1 and Erk2 kinases by FGF-2 also required the presence of 6-O-sulfate groups. Sulfation at 2-O- and 6-O-positions was moreover a prerequisite for binding of heparin to a lysine-rich peptide corresponding to amino acids 160-177 in the extracellular domain of FGFR-1. Selectively 6-O-desulfated heparin, which binds to FGF-2 but fails to bind the receptor, decreased FGF-2-induced proliferation of CHO677 cells, presumably by displacing intact heparin. Furthermore, FGF-2-induced angiogenesis in chick embryos was inhibited by 6-O-desulfated heparin. Thus, formation of a ternary complex of FGF-2, heparin, and FGFR-1 appears critical for the activation of FGFR-1 kinase and downstream signal transduction. Preventing complex formation by modified heparin preparations may allow regulation of FGF-2 functions, such as induction of angiogenesis.

Evolution of the neuropeptide Y receptor family: gene and chromosome duplications deduced from the cloning and mapping of the five receptor subtype genes in pig.

Neuropeptide Y (NPY) receptors mediate a variety of physiological responses including feeding and vasoconstriction. To investigate the evolutionary events that have generated this receptor family, we have sequenced and determined the chromosomal localizations of all five presently known mammalian NPY receptor subtype genes in the domestic pig, Sus scrofa (SSC). The orthologs of the Y(1) and Y(2) subtypes display high amino acid sequence identities between pig, human, and mouse (92%-94%), whereas the Y(4), Y(5), and y(6) subtypes display lower identities (76%-87%). The lower identity of Y(5) is due to high sequence divergence in the large third intracellular loop. The NPY1R, NPY2R, and NPY5R receptor genes were localized to SSC8, the NPY4R to SSC14, and NPY6R to SSC2. Our comparisons strongly suggest that the tight cluster of NPY1R, NPY2R, and NPY5R on human chromosome 4 (HSA4) represents the ancestral configuration, whereas the porcine cluster has been split by two inversions on SSC8. These 3 genes, along with adjacent genes from 14 other gene families, form a cluster on HSA4 with extensive similarities to a cluster on HSA5, where NPY6R and >13 other paralogs reside, as well as another large cluster on HSA10 that includes NPY4R. Thus, these gene families have expanded through large-scale duplications. The sequence comparisons show that the NPY receptor triplet NPY1R-NPY2R-NPY5R existed before these large-scale duplications.

Gene duplications in early metazoan evolution.

Major increases in complexity during animal evolution occurred at the transition from a unicellular protozoan to a multicellular metazoan, the evolution of Bilateria from diploblasts (possibly the Cambrian explosion) and during early vertebrate evolution. A role for gene duplication in the third event has been widely discussed. Here I examine the possible role of gene duplications and domain shuffling in the first two events. There is evidence for a wave of gene duplications and shuffling which may have paved the way for multicellularity; there are also examples of gene duplications that may have facilitated the transition from diploblasts to Bilateria.

Allergic and non-allergic students' perception of the same high school environment.

The aim of the study was to describe how allergics and non-allergics perceive the same environment. All high school students in a town in southern Sweden were invited to answer a questionnaire concerning allergy, subjective symptoms, annoyance reactions and perception of the environment (response rate: 81%). The results show that only 45% of the students were non-allergic (n = 1,715). Since the symptom frequency among non-allergic students was normal, the schools were classified as healthy. However, compared to the non-allergic students, a higher percentage among the allergics suffered from symptoms every week, a lower percentage was satisfied with the air quality and the cleaning, and a higher percentage was bothered every week by temperature, stuffy/stale air, bad odor, passive smoke, bad lighting, noise, dust and dirt (ANOVA, P < 0.05). The findings could indicate that allergics note discomfort earlier than non-allergics by being more critical in general and especially critical to factors that could effect their health. The findings could also indicate that awareness of ones own sensitivity could lead to attention to different risk factors, which in turn could lead to stress/anxiety, which could make symptoms worse. The conclusion is that it is important to take allergy into consideration when the environment is assessed.

Lampetra fluviatilis neurotrophin homolog, descendant of a neurotrophin ancestor, discloses the early molecular evolution of neurotrophins in the vertebrate subphylum.

We have isolated a neurotrophin from the lamprey that permitted us to perform a phylogenetic analysis of the neurotrophin gene family that dates back more than 460 million years to the early vertebrate ancestors. The results show that the neurotrophin gene family was originally formed by two subsequent duplications. The duplication that formed nerve growth factor, neurotrophin-3, brain-derived neurotrophic factor, and neurotrophin-4/5 occurred after the split of lampreys but before the split of cartilaginous fish from the main vertebrate lineage. Compilation of chromosomal gene maps around the neurotrophins shows that they are located in paralogous regions, suggesting that the genes were formed at major duplication events possibly by complete genome doubling. Analysis of two isolated Trk receptor sequences shows similar results as for the lamprey neurotrophin. Multiple neurotrophin and Trk genes, including neurotrophin-6 and -7, have been found in bony fish, and we suggest that the extra genes were formed by an additional duplication in the bony fish lineage. Analysis of lamprey Trk mRNA expression in the adult brain shows that the genes are expressed in all regions analyzed so far. Together, the results suggest that the duplications of ancestral neurotrophin and Trk genes at an early vertebrate stage have permitted evolution to bring about differential neurotrophin and Trk expression, thereby allowing the formation of specific functions in selective neuronal populations.

Research utilization and improvement in outcomes after diagnostic cardiac catheterization.

This research utilization project helped summarize the research basis of current practice related to duration of bed rest after cardiac catheterization via the femoral artery. Several physicians have changed their practice as a result of this project, and the safety of patients is being maintained. Interestingly, De Jong and Morton recently published a research analysis of interventions used to control vascular complications after cardiac catheterization. These authors concluded from the review of the literature on duration of bed rest that evidence was sufficient to support a change in practice. Because we thought that the published evidence was insufficient to be used as the sole basis for a change in practice, we continued to follow the Iowa model. Specifically, we integrated scientific principles and expert recommendations with the published research base; recommended a change in practice; and monitored patients' outcomes, which ultimately did confirm the recommendations of De Jong and Morton. We are convinced that the combination of data from our own patients and the review of the literature was helpful to assure our medical and nursing staff that this change in practice was safe. This project illustrates the benefit of using the Iowa Model for Research Based Practice to Promote Quality Care as a guide to improve patients' outcomes.

Evolution of the vertebrate genome as reflected in paralogous chromosomal regions in man and the house mouse.

Gene constellations on several human chromosomes are interpreted as indications of large regional duplications that took place during evolution of the vertebrate genome. Four groups of paralogous chromosomal regions in man and the house mouse are suggested and are believed to be conserved remnants of the two or three rounds of tetraploidization that are likely to have occurred during evolution of the vertebrates. The phenomenon of differential silencing of genes is described. The importance of conservation of linkage of particular genes is discussed in relation to genetic regulation and cell differentiation.

Involvement of transforming growth factor-beta in the formation of fibrotic lesions in carcinoid heart disease.

Carcinoid heart disease is a complication of a neuroendocrine carcinoid tumor. Morphologically, it is characterized by the formation of fibrotic plaques with deposition of extracellular matrix in the subendocardium, frequently causing heart valve dysfunction and cardiac failure. Because members of the transforming growth factor-beta (TGF-beta) family are known to stimulate fibroblasts in their production of extracellular matrix, we investigated the expression of the three isoforms of TGF-beta and the binding protein for latent TGF-beta 1 (LTBP) in carcinoid plaques of the right side of the heart, as well as from control tissue, using immunohistochemistry. Tissue specimens were obtained intraoperatively from nine consecutive patients undergoing valve replacement surgery. TGF-beta 1 and TGF-beta 3 were detected in the fibroblasts of all plaques analyzed, whereas TGF-beta 2 was only rarely expressed. The localization of LTBP was partly concordant with that of TGF-beta 1, but the positive staining for LTBP was extracellular. Sections from unaffected heart tissue contained few fibroblasts in the subendocardium, showing only weak or no immunostaining for TGF-beta 1, -beta 2, and -beta 3 and no staining for LTBP. These results suggest that TGF-beta may play a role in the proliferation of fibroblasts and their matrix production in carcinoid heart lesions.

Schistosome antigen gp50 is responsible for serological cross-reactivity with Trichinella spiralis.

The 50-kDa component (gp50) present in Schistosoma mansoni eggs and secretions of the various life stages of the parasite was recognized by experimentally infected mice and by humans with S. mansoni, Schistosoma haematobium, and Schistosoma japonicum infection. All sera reacting with crude S. mansoni-soluble egg antigens (SEA) also reacted strongly with gp50 in enzyme-linked immunosorbent assay. No reactivity against gp50 was seen with sera from individuals without schistosomiasis, with the exception of sera from patients with Trichinella spiralis infection. All of 10 sera from patients with trichinellosis also reacted with schistosomes by immunofluorescence essentially recognizing testes, ovaries, ootype epithelium and ducts of the reproductive system. Cross-reacting antigens were seen in T. spiralis hypodermis, stichocytes and possibly germinal primordia using anti-gp50 monoclonal antibodies and anti-gp50-positive schistosomiasis patient sera. The results suggest that the anti-gp50 antibody response constitutes a significant part of the anti-SEA antibody response in infected individuals and is a major reason for the previously recognized serological cross-reactivity between T. spiralis and schistosome species.

Identification of a parasite-specific cytoplasmic 67 kDa Entamoeba histolytica antigen recognized by patient sera and monoclonal antibodies.

To avoid false positive reactions in tests for anti-ameba antibodies, we wanted to identify parasite-specific component(s). Amebiasis patient sera recognized an antigen of 67 kDa by immunoblotting in an active E. histolytica fraction obtained by ion exchange chromatography. Monoclonal antibodies against the fraction were made. Antibody 3G2 reacted with three antigenic components of 67, 40 and 25 kDa and in the immunocytology with an epitope located in the cytoplasm of E. histolytica trophozoites. ELISAs using the isolated parasite fraction and monoclonal antibody 3G2 (to assay inhibition of binding) were capable of distinguishing specific reactivity in sera from amebiasis patients.

Isolation of an SBA lectin-reactive glycoprotein (gp50) and its identification in Schistosoma mansoni larval and adult worm secretions.

A major 50-kDa soybean agglutinin (SBA)-reactive component present in extracts of Schistosoma mansoni eggs was isolated by SBA lectin affinity chromatography. In polyacrylamide gel electrophoresis (PAGE), the SBA-reactive component was seen as a 100-kDa polypeptide band that after reduction and alcylation was substituted by a 50-kDa component. This suggests that it occurs in native form as a dimer. Monoclonal antibodies produced against gp50 reacted with miracidial and cercarial secretions and with adult worm components including tegumental structures suggestive of a secretory function.

Histochemical and immunohistochemical morphology of carcinoid heart disease.

Histochemical and immunohistochemical investigations were performed on tissue obtained from the right heart side in three patients subjected to valve, replacement operations because of severe carcinoid heart disease. Extensive fibrotic changes were present on the endocardium of the right atrium, the papillary muscles of the tricuspid valve and the leaflets of the tricuspid and pulmonic valves of all patients. The main constituent of the lesions was a stroma with abundant acid mucopolysaccharides and collagen but devoid of stainable elastic components. The lesions were in some areas sharply delineated from the normal endocardium, but often also extended into the endocardium and myocardium. Small to medium sized vessels were demonstrated histochemically in the lesions and confirmed by positive immunoreaction against endothelial and smooth muscle cells. The moderate number of mesenchymal cells within the lesions had immunoreactivity consistent with muscle cells which seemed to have a very low proliferating activity. The histochemical and immunohistochemical techniques used confirmed some earlier observations in carcinoid heart disease but also rendered new information contradicting previous findings. The infiltrative nature of the carcinoid plaque gives a new dimension to the carcinoid heart disease. The etiology still remains obscure and well known growth factors for connective tissue such as platelet derived growth factor (PDGF) do not seem to be directly involved in the process.