Identification and purification of human T-lymphocyte colony-enhancing factor, TLCEF: increased production by phorbol myristate acetate.

T-lymphocyte colony-enhancing factor (TLCEF), a growth factor for a minute subpopulation of T lymphocytes, is produced, along with other factors, by conditioned media (CM) of mononuclear cells following stimulation with T mitogens, such as phytohaemagglutinin (PHA). A combination of PHA and a co-mitogen, phorbol 12-myristate 13-acetate (PMA), has been shown to have a synergistic effect on the production of TLCEF, yielding levels of activity eight to fifteen times higher than those obtained with either PHA or PMA alone. TLCEF was purified by ammonium sulphate, fractionation hydrophobic interaction chromatography on phenyl-Sepharose and gel filtration. The last step of this purification procedure yielded two peaks of activity purified 13,000- and 29,000-fold, respectively. The first peak eluted from the column with an average molecular weight of 125,000, whereas the second peak was retained on the gel, probably due to non-specific interactions with it. The purified fractions contained none of the following activities: T-cell growth factor (TCGF), colony-stimulating factor-1 (CSF-1), interleukin-3 (IL-3) and interferon. TCGF activity, which is known to be unstable at high degrees of purification, was already lost after the ammonium sulphate fractionation step, most probably because of the low protein and albumin concentrations (0.33 and 0.11 mg/ml, respectively). TLCEF is thus a more stable immunoregulatory factor than TCGF and has a much higher apparent molecular weight.     

Diabetes insipidus, diabetes mellitus, optic atrophy and deafness (DIDMOAD) caused by mutations in a novel gene (wolframin) coding for a predicted transmembrane protein

Wolfram syndrome is an autosomal recessive disorder characterized by juvenile diabetes mellitus, diabetes insipidus, optic atrophy and a number of neurological symptoms including deafness, ataxia and peripheral neuropathy. Mitochondrial DNA deletions have been described in a few patients and a locus has been mapped to 4p16 by linkage analysis. Susceptibility to psychiatric illness is reported to be high in affected individuals and increased in heterozygous carriers in Wolfram syndrome families. We screened four candidate genes in a refined critical linkage interval covered by an unfinished genomic sequence of 600 kb. One of these genes, subsequently named wolframin, codes for a predicted transmembrane protein which was expressed in various tissues, including brain and pancreas, and carried loss-of- function mutations in both alleles in Wolfram syndrome patients.      

Suppression of peroxisomal membrane protein defects by peroxisomal ATP binding cassette (ABC) proteins

X-Linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder characterized by reduced peroxisomal very long chain fatty acid (VLCFA) beta-oxidation. The X - ALD gene product (ALDP) is a peroxisomal transmembrane protein with an ATP binding cassette (ABC). ALDP and three other ABC proteins (PMP70, ALDR, P70R) localize to the peroxisomal membrane. The function of this family of peroxisomal membrane proteins is unknown. We used complementation studies to begin analysis of their role in VLCFA beta-oxidation and on the peroxisomal membrane. Expression of either ALDP or PMP70 restores VLCFA beta- oxidation in X-ALD fibroblasts, indicating overlapping functions. Their expression also restores peroxisome biogenesis in cells that are deficient in the peroxisomal membrane protein Pex2p. Thus it is likely that complex protein interactions are involved in the function and biogenesis of peroxisomal membranes that may contribute to disease heterogeneity.      

Methylprednisolone exacerbates axonal loss following optic nerve trauma in rats

The excitability of human axons can be studied reliably using the technique of threshold tracking, which allows the strength of a test stimulus to be adjusted by computer to activate a defined fraction of the maximal nerve or muscle action potential. The stimulus current that just evokes the target response is considered the 'threshold' for that response. More useful than the resting threshold are other indices of axonal excitability derived from pairs of threshold measurements, such as refractoriness, supernormality, strength-duration time constant and 'threshold electrotonus' (i.e. the changes in threshold produced by long-lasting depolarizing or hyperpolarizing current pulses). Each of these measurements depends on membrane potential and on other biophysical properties of the axons. Together they can provide new information about the pathophysiology underlying abnormalities in excitability in neuropathy.     

Development of a research netwrok for emerging foodborne pathogens in Germany

A network of epidemiologists, microbiologists, veterinarians, and clinicians is being developed in Germany to support local and state health departments and veterinary authorities in their research and epidemiological investigations on emerging foodborne     

Experiences with the Butler procedure for overlapping fifth toe

Overlapping fifth toe is a finding in pediatric orthopaedics which rarely requires operative therapy. PATIENTS AND METHOD: Between Jan. 1, 1992 and Dec. 31, 2002 five operations of an overlapping fifth toe using the Butler procedure were performed at a mean patients age of 5.5 years (min: 3, max: 9). All patients were clinically evaluated after a mean follow-up of 6 years (min: 2, max: 10) according to the score of Black. We present the technique of the Butler procedure and discuss the relevant literature. RESULTS: An excellent result was achieved in all patients. Despite the extensive soft tissue release no complications could be found. CONCLUSION: The Butler procedure is a simple and safe procedure without any need of immobilisation.     

Comparing biomechanical investigations about different wiring techniques of finger joint arthrodesis

Introduction Multiple operative techniques are currently used for finger arthrodesis in clinical practice. The present study was designed to compare the biomechanical characteristics of typical arthrodesis techniques used in daily practice.Material and methods Osteosynthesis techniques comprising wire cerclage, thread cerclage (PDS) or intraosseous wire suture were compared in a biomechanical experiment for resistance against bending loads. The mentioned techniques were applied to artificial specimens with resected articular surfaces or by using the cup-and-cone procedure. In this process, the specimens were tested using various Kirschner-wire insertion angles as well as different arthrodesis angles (20° vs 40°) in a 4-point bending test with each group consisting of 6 specimens of acrylic glass. The forces prevalent in the joint space were determined by prescale pressure measurement foils.Results Wire tension banding resisted significantly higher bending moments than arthrodeses with thread tension bands (p<0.05). All set-ups with tension banding techniques tolerated significantly higher loads than the intraosseous wire sutures without additional K-wires (p<0.05), which showed unfavorable dislocation of contact areas resulting in instability even under relatively minor bending loads. Using the cup-and-cone technique, a geometrically larger contact area could be achieved between two unloaded fragments, but this technique showed no advantages in the opposing bending moments compared with the conventional resection method. In both techniques, a dislocation of contact surfaces towards the palmar direction could be observed with increasing bending moment. While the use of thread tension band fixation reduces the risk of plastic deformation of both osteosynthetic material and bone stock, the problem of resorption rate has to be taken into account when choosing the material for the thread.Conclusions Considering pressure distribution and stability with and without bending loads, it is not the most rigid osteosynthesis technique which should be viewed as the ideal treatment. In contrast, it is more important to consider the various and most likely conditions to be expected in daily life after arthrodesis and therefore to chose the type of technique distributing pressure as regularly as possible.