Evaluation of risk profiles by subcutaneous adipose tissue topography in obese juveniles

Objective: To compare subcutaneous adipose tissue topography (SAT‐top) in obese juveniles with age‐matched normal‐weight controls. Research Methods and Procedures: The optical device LIPOMETER (European Patent EP 0516251) enables the non‐invasive, rapid, safe, and precise measurement of the thickness of subcutaneous adipose tissue. Fifteen defined body sites (1 = neck to 15 = calf) characterize the individual SAT‐top like an individual fingerprint. SAT‐top of 1351 juveniles (obese: 42 boys, 59 girls, normal weight: 680 boys, 570 girls) from 7 to 19 years of age were measured. For visual comparison, the 15‐dimensional SAT‐top information was condensed by factor analysis into a two‐dimensional factor plot. Results: Both female and male obese juveniles had markedly increased adipose tissue layers at 7 = upper abdomen, 8 = lower abdomen, 5 = front chest, and 6 = lateral chest. The pubertal changes of body shape and fat distribution of the normal‐weight boys and girls (boys show thinner adipose tissue layers on their legs, whereas girls had thicker adipose tissue layers at the extremities) were not seen in the obese group. Independently of age and sex, all of the obese juveniles showed a similar, more android body fat distribution with increased trunk fat. Discussion: SAT‐top of the obese juveniles is similar to that of patients with type 2 diabetes, polycystic ovary syndrome, and coronary heart disease. Patients with these metabolic disorders and obese juveniles are located in the factor plot in the same area. This body shape may indicate a risk profile for developing polycystic ovary syndrome (women), type 2 diabetes, and early atherosclerosis (both sexes).     

A comparison of two in vitro maturation media for use with adult porcine oocytes for adult somatic cell nuclear transfer

Two media used to mature adult porcine oocytes for somatic cell nuclear transfer were compared. In the first experiment, parthenogenetic embryos were produced using a maturation medium used by us previously to clone pigs (OMM199) and that described by Kühholzer et al. (2001) to transport oocytes overnight (BOMED). There was no difference in maturation rates between the two different media. However, BOMED medium increased the percentage of parthenogenetic embryos that developed to the blastocyst stage compared with OMM199 (49% vs. 29%, respectively). In a second experiment, BOMED medium increased the percentage of SCNT embryos that developed to the blastocyst stage compared with OMM199 (22% vs. 8%, respectively). The efficiency of our cloning protocol using adult oocytes matured in BOMED medium was then determined by transferring SCNT embryos reconstructed using adult fibroblasts to synchronized recipients. Primary cultures of adult fibroblasts were obtained from two adult male pigs and used for SCNT (passages 2-4). Between 82 and 146 fused couplets were transferred to seven recipients synchronized 1 day behind the embryos. Five recipients (71% pregnancy rate) subsequently farrowed a total of 23 piglets (4.4 average litter size). Overall efficiencies (liveborn/embryos transferred) were 3.2% for all transfers and 4.3% for animals that gave birth.     

Identification of three phases in Onconase refolding

Onconase is an extremely stable member of the RNase A superfamily. The increase in the thermodynamic stability by 20 kJ x mol(-1) in comparison to RNase A was expected to result in altered folding behavior. Despite the lack of cis-Pro residues in native Onconase, refolding at low concentrations of guanidine hydrochloride was complex and showed three kinetic phases (fast, medium, and slow), with rate constants differing by a factor of about 10 each. None of the phases could be accelerated by peptidyl-prolyl cis-trans isomerases, pointing to the absence of kinetic phases that are limited by Pro isomerization. The detailed analysis by various probes indicates that the burial of the N-terminal Trp3, which is associated with the restoration of the active site, occurs in the slow phase, i.e. in the last step of refolding. Evidently, in contrast to the folding of RNase A, there is no catalytically active native-like intermediate in the folding of Onconase.     

Insights into the structure of plant alpha-type phospholipase D

Phospholipases D play an important role in the regulation of cellular processes in plants and mammals. Moreover, they are an essential tool in the synthesis of phospholipids and phospholipid analogs. Knowledge of phospholipase D structures, however, is widely restricted to sequence data. The only known tertiary structure of a microbial phospholipase D cannot be generalized to eukaryotic phospholipases D. In this study, the isoenzyme form of phospholipase D from white cabbage (PLDalpha2), which is the most widely used plant phospholipase D in biocatalytic applications, has been characterized by small-angle X-ray scattering, UV-absorption, CD and fluorescence spectroscopy to yield the first insights into its secondary and tertiary structure. The structural model derived from small-angle X-ray scattering measurements reveals a barrel-shaped monomer with loosely structured tops. The far-UV CD-spectroscopic data indicate the presence of alpha-helical as well as beta-structural elements, with the latter being dominant. The fluorescence and near-UV CD spectra point to tight packing of the aromatic residues in the core of the protein. From the near-UV CD signals and activity data as a function of the calcium ion concentration, two binding events characterized by dissociation constants in the ranges of 0.1 mm and 10-20 mm can be confirmed. The stability of PLDalpha2 proved to be substantially reduced in the presence of calcium ions, with salt-induced aggregation being the main reason for irreversible inactivation.     

Resource pulses,species interactions,and diversity maintenance in arid and semi-arid environments

Arid environments are characterized by limited and variable rainfall that supplies resources in pulses. Resource pulsing is a special form of environmental variation, and the general theory of coexistence in variable environments suggests specific mechanisms by which rainfall variability might contribute to the maintenance of high species diversity in arid ecosystems. In this review, we discuss physiological, morphological, and life-history traits that facilitate plant survival and growth in strongly water-limited variable environments, outlining how species differences in these traits may promote diversity. Our analysis emphasizes that the variability of pulsed environments does not reduce the importance of species interactions in structuring communities, but instead provides axes of ecological differentiation between species that facilitate their coexistence. Pulses of rainfall also influence higher trophic levels and entire food webs. Better understanding of how rainfall affects the diversity, species composition, and dynamics of arid environments can contribute to solving environmental problems stemming from land use and global climate change.     

A putative ariadne-like E3 ubiquitin ligase (PAUL) that interacts with the muscle-specific kinase (MuSK)

Formation of the postsynaptic membrane at the skeletal neuromuscular junction (NMJ) requires activation of the muscle-specific receptor tyrosine kinase (MuSK). Few intracellular mediators or modulators of MuSK actions are known. E3 ubiquitin ligases may serve this role, because activities of several receptor tyrosine kinases, G-protein-coupled receptors and channels are modulated by ubiquitination. Here, we report identification of a putative Ariadne-like ubiquitin ligase (PAUL) that binds to the cytoplasmic domain of MuSK. PAUL is expressed in numerous tissues of developing and adult mice, and is present at NMJs in muscle fibers but is not confined to them.     

A link of Ca<Superscript>2+</Superscript> to cAMP oscillations in <Emphasis Type="Italic">Dictyostelium</Emphasis>: the calmodulin antagonist W-7 potentiates cAMP relay and transiently inhibits the acidic Ca<Superscript>2+</Superscript>-store

Background  

During early differentiation of Dictyostelium the attractant cAMP is released periodically to induce aggregation of the cells. Here we pursue the question whether pulsatile cAMP signaling is coupled to a basic Ca²⁺-oscillation.     

Gene therapy: prospects for glycolipid storage diseases

Lysosomal storage diseases comprise a group of about 40 disorders, which in most cases are due to the deficiency of a lysosomal enzyme. Since lysosomal enzymes are involved in the degradation of various compounds, the diseases can be further subdivided according to which pathway is affected. Thus, enzyme deficiencies in the degradation pathway of glycosaminoglycans cause mucopolysaccharidosis, and deficiencies affecting glycopeptides cause glycoproteinosis. In glycolipid storage diseases enzymes are deficient that are involved in the degradation of sphingolipids. Mouse models are available for most of these diseases, and some of these mouse models have been used to study the applicability of in vivo gene therapy. We review the rationale for gene therapy in lysosomal disorders and present data, in particular, about trials in an animal model of metachromatic leukodystrophy. The data of these trials are compared with those obtained with animal models of other lysosomal diseases.