Mechanical effects of continuous passive motion on the lumbar spine in seating

The aim of this study was to develop a model which describes the mechanical spinal response to small alternating pelvic stimulation induced by an active rotational movement of a normal chair. The rotary continuous passive motion (RCPM) of the seat about a vertical axis of only 0.6 degrees resulted in an increased in spinal length as opposed to the normal daily shrinkage, and back patients experienced pain relief. Passive and active exercies have been broadly applied for treating and healing spinal disorders. A rigid body package (ADAMS Android) was used to translate the stimulation of the ischial tubersoity in caudo-cranial handing-over visualisation. The parameters of the model were set so that the values of the global stiffness and geometry of the intervertebral discs could be changed. In vivo validation of the model was based on force and moment measurements using an internal AO fixator. The predicitons of the model concerning natural frequency (4.5Hz) in vertical direction and the axial torsion response on small pelvic torsion are comparable with experimental data.     

Protein–Protein and Protein–Membrane Associations in the Lignin Pathway

Supramolecular organization of enzymes is proposed to orchestrate metabolic complexity and help channel intermediates in different pathways. Phenylpropanoid metabolism has to direct up to 30% of the carbon fixed by plants to the biosynthesis of lignin precursors. Effective coupling of the enzymes in the pathway thus seems to be required. Subcellular localization, mobility, protein–protein, and protein–membrane interactions of four consecutive enzymes around the main branch point leading to lignin precursors was investigated in leaf tissues of Nicotiana benthamiana and cells of Arabidopsis thaliana. CYP73A5 and CYP98A3, the two Arabidopsis cytochrome P450s (P450s) catalyzing para- and meta-hydroxylations of the phenolic ring of monolignols were found to colocalize in the endoplasmic reticulum (ER) and to form homo- and heteromers. They moved along with the fast remodeling plant ER, but their lateral diffusion on the ER surface was restricted, likely due to association with other ER proteins. The connecting soluble enzyme hydroxycinnamoyltransferase (HCT), was found partially associated with the ER. Both HCT and the 4-coumaroyl-CoA ligase relocalized closer to the membrane upon P450 expression. Fluorescence lifetime imaging microscopy supports P450 colocalization and interaction with the soluble proteins, enhanced by the expression of the partner proteins. Protein relocalization was further enhanced in tissues undergoing wound repair. CYP98A3 was the most effective in driving protein association.     

Male bimaturism and reproductive success in Sumatran orang-utans

Although orang-utans live solitary lives most of the time, theyhave a complex social structure and are characterized by extremesexual dimorphism. However, whereas some adult male orang-utansdevelop full secondary sexual characteristics, such as cheekflanges, others may stay in an "arrested" unflanged conditionfor up to 20 years after reaching sexual maturity. The resultis a marked bimaturism among adult males. Flanged males allowfemales to overlap with their home range and often toleratethe presence of unflanged males. However, wherever possibleflanged males actively prevent unflanged males from copulatingwith females. Two competing hypotheses, previously untested,have been advanced to explain male reproductive behavior andbimaturism in orang-utans: (1) the "range-guardian" hypothesis,which asserts that the flanged males are postreproductive anddefend a range in which they tolerate sexually active, unflangedmale relatives; and (2) the "female choice" hypothesis, whichasserts that flanged males tolerate unflanged males in their range because they rely on female preference to favor flangedmales. We investigated these hypotheses and a third hypothesisthat the two male morphs represent co-existing alternativemale reproductive strategies ("sitting, calling, and waiting"for flanged males versus "going, searching, and finding" forunflanged males). Fecal samples were collected from a well-studiedpopulation in Indonesia, and eight human microsatellites wereanalyzed for 30 individuals that have been behaviorally monitoredfor up to 27 years. By carrying out paternity analysis on 11offspring born over 15 years, we found that unflanged malesfathered about half (6) of the offspring. Relatedness betweensuccessful unflanged males and resident dominant males wassignificantly lower than 0.5, and for some unflanged/flangedmale pairs, relatedness values were negative, indicating thatunflanged males are not offspring of the flanged males.     

First report of Eotetranychus fagi in Belgium

Eotetranychus fagi (Acari: Tetranychidae) was first recorded in Belgium on Fagus sylvatica in Kortrijk in October 2002. In the autumn of 2003 E. fagi was noticed again at several locations in Flanders. Because F. sylvatica is often used as hedge plants in private gardens, it is expected that further spread of this spider mite will occur in the next few years.     

Genotypic diversity, antimicrobial resistance, and virulence factors of human isolates and probiotic cultures constituting two intraspecific groups of Enterococcus faecium isolates

The intraspecific relationships among a collection of Enterococcus faecium isolates comprising probiotic cultures and human clinical isolates were investigated through the combined use of two high-resolution DNA-fingerprinting techniques. In addition, the incidences of antimicrobial resistance and virulence traits were investigated. A total of 128 E. faecium isolates from human clinical or nonclinical sources or used as probiotic cultures were subjected to fluorescent amplified fragment length polymorphism (FAFLP) fingerprinting and pulsed-field gel electrophoresis (PFGE) analysis of SmaI macrorestriction patterns. Susceptibilities to 16 antimicrobial agents were tested using broth microdilution, and the presence of the corresponding resistance genes was investigated using PCR. Multiplex PCR was used to detect the presence of the enterococcal virulence genes asa1, gelE, cylA, esp, and hyl. The results of the study showed that two intraspecific genomic groups (I and II) were obtained in FAFLP analysis. PFGE analysis demonstrated high variability within these two groups but also indicated that some probiotic cultures were indistinguishable and that a number of clinical isolates may be reisolations of commercial probiotic cultures. Compared to group II, which contained the majority of the probiotic isolates and fewer human clinical isolates, higher phenotypic and genotypic resistance frequencies were observed in group I. Two probiotic isolates were phenotypically resistant to erythromycin, one of which contained an erm(B) gene that was not transferable to enterococcal recipients. None of the probiotic E. faecium isolates demonstrated the presence of the tested virulence genes. The previously reported observation that E. faecium consists of two intraspecific genomic groups was further substantiated by FAFLP fingerprinting of 128 isolates. In combination with antimicrobial resistance and virulence testing, this grouping might represent an additional criterion in assessing the safety of new potential probiotic E. faecium isolates.     

Evaluation of parental mitochondrial inheritance in neonates born after intracytoplasmic sperm injection.

Intracytoplasmic sperm injection (ICSI) is now used when severe male-factor infertility has been documented. Since defective mitochondrial functions may result in male hypofertility, it is of prime importance to evaluate the risk of paternal transmission of an mtDNA defect to neonates. DNA samples from the blood of 21 infertile couples and their 27 neonates born after ICSI were studied. The highly polymorphic mtDNA D-loop region was analyzed by four PCR-based approaches. With denaturing gradient gel electrophoresis (DGGE), which allows 2% of a minor mtDNA species to be detected, the 27 newborns had a DGGE pattern identical to that of their mother but different from that of their father. Heteroplasmy documented in several parents and children supported an exclusive maternal inheritance of mtDNA. The parental origin of the children's mtDNA molecules also was studied by more-sensitive assays: restriction-endonuclease analysis (REA) of alpha[32P]-radiolabeled PCR products; paternal-specific PCR assay; and depletion of maternal mtDNA, followed by REA. We did not detect paternal mtDNA in nine neonates, with a sensitivity level of 0.01% in five children, 0.1% in two children, and 1% in two children. The estimated ratio of sperm-to-oocyte mtDNA molecules in humans is 0.1%-1.5%. Thus, we conclude that, in these families, the ICSI procedure performed with mature spermatozoa did not alter the uniparental pattern of inheritance of mtDNA.     

Synthesis and biological evaluation of conformationally restricted derivatives of tryptophan as NK1/NK2 ligands

Chemical modifications on the NK₁ competitive antagonist L-732,138, with a view to creating a dual NK₁/NK₂ ligand, led to the tryptophan derivative 1 possessing the protected Gly-Leu sequence of the C-terminus of substance P and neurokinin A. Modifications in the nature of the carbamate function increased the selectivity for the NK₁ receptor, whereas the inclusion of the indole moiety in -carboline or carbazole rings decreased the affinity for both receptors. Free indolylmethyl and Cbz carbamate groups were shown to be essential for NK₂ affinity.