Assessment of motion of a swing leg and gait rehabilitation with a gravity balancing exoskeleton.

The gravity balancing exoskeleton, designed at University of Delaware, Newark, consists of rigid links, joints and springs, which are adjustable to the geometry and inertia of the leg of a human subject wearing it. This passive exoskeleton does not use any motors but is designed to unload the human leg joints from the gravity load over its range-of-motion. The underlying principle of gravity balancing is to make the potential energy of the combined leg-machine system invariant with configuration of the leg. Additionally, parameters of the exoskeleton can be changed to achieve a prescribed level of gravity assistance, from 0% to 100%. The goal of the results reported in this paper is to provide preliminary quantitative assessment of the changes in kinematics and kinetics of the walking gait when a human subject wears such an exoskeleton. The data on kinematics and kinetics were collected on four healthy and three stroke patients who wore this exoskeleton. These data were computed from the joint encoders and interface torque sensors mounted on the exoskeleton. This exoskeleton was also recently used for a six-week training of a chronic stroke patient, where the gravity assistance was progressively reduced from 100% to 0%. The results show a significant improvement in gait of the stroke patient in terms of range-of-motion of the hip and knee, weight bearing on the hemiparetic leg, and speed of walking. Currently, training studies are underway to assess the long-term effects of such a device on gait rehabilitation of hemiparetic stroke patients.     

The effects of dopexamine. Transpulmonary shunt volume in thoracic surgical procedures with one-lung respiration

To evaluate the respective interest of amikacin and isepamicin in P. aeruginosa infection, the resistance level was ascertained using the disk method. Susceptibility was also tested for gentamicin, tobramycin and netilmicin. Isolates came from three surgical units and from two intensive care units. Serotyping was proceeded, and isolates coming from the same patient, with the same susceptibility pattern and the same serotype was included once only: 197 strains were thus obtained. Resistance level was 22.3% for amikacin, and 28.4% for isepamicin. Discrepancies were found in 14.7% of cases (major: 8.1%; minor: 6.6%). Discordant strains were more susceptible to amikacin than to isepamicin in 30/37 cases, and more susceptible to isepamicin in 7/37 cases. This difference was highly significant (paired Chi-2 test: p < 10(-4). The best susceptibility to amikacin was found in all serotypes and units.     

Routine molecular genotyping of HLA-B27 in spondyloarthropathies overcomes the obstacles of serological typing and reveals an increased B *2702 frequency in ankylosing spondylitis

OBJECTIVE: To evaluate the reproducibility and reliability of polymerase chain reaction (PCR) in HLA-B27 typing compared to the conventionally used microlymphocytotoxicity test (MLCT). To determine the HLA-B27 subtype frequencies (B*2701-B*2709) in patients with HLA-B27 associated disease and healthy persons using sequence specific oligonucleotides (SSO). METHODS: 398 consecutive patients were HLA-B27 typed by MLCT and PCR. Subtyping by SSO was performed in 142 patients with HLA-B27 associated disease [ankylosing spondylitis (AS) n = 38, reactive arthritis 44, undifferentiated spondyloarthropathy (uSpA) 45, psoriatic arthritis 15] and 125 healthy HLA-B27 controls. RESULTS: MLCT identified 61 HLA-B27 positive patients (15.3%); PCR identified 78 positive patients (19.6%). MLCT gave false negative results for 8 patients (2.0%) and false positives for a further 7 (1.8%). Only subtypes B*2702 and B*2705 were present in patients and controls. Overall frequencies of B*2702 in patients and controls were 14.1 and 9.6%, respectively. The B*2702 frequency was significantly (pcorr. < 0.04) higher in AS (23.7%) and lower in uSpA (6.7%) patients. CONCLUSION: HLA-B27 typing by PCR is reliable and reproducible and therefore recommended for routine typing. It overcomes the obstacles of serological typing, i.e., equivocal results and cross-reactivity. In addition, subtype frequencies (B*2702 and B*2705) are equally distributed among patients and controls, although subtype B*2702 seems to be more frequent in AS and less so in uSpA.     

Investigations of gas-particle-lance flows at high velocity for the injection of solid in melting baths

For the injection of gas and solid into molten masses using lances the situation at the lance outlet is a boundary condition for the mixing in the melting bath and therefore an important parameter for the energy and mass exchanges which take place there. In the scope of the main research programme of the Deutsche Forschungsgemeinschaft named “Mischung mit Energie-und Stoffumsatz in schmelzmetallurgischen Systemen”, a mathematical model is to be developed at the Institut für Energieverfahrenstechnik der Technischen Universität Clausthal, which should make it possible to calculate the situation at the outlet of a lance operating with gas and solid, using operational and geometrical parameters (pressure at lance intake, amount of solid, length and diameter of lance) which can be freely chosen.     

Expression of a hypoglycosylated form of CD86 (B7-2) on human T cells with altered binding properties to CD28 and CTLA-4

CD80 (B7-1) and CD86 (B7-2) on APC provide a major costimulatory signal through interactions with CD28 on T cells. Absent from resting human T cells, CD86 is up-regulated early upon T cell activation, whereas CD80 expression appears later. Whereas T cell expression of CD80 has been implicated in costimulation, the functional significance of CD86 expression on T cells is unclear. We now demonstrate that CD86 expressed on human CD4+ T cell clones does not provide a costimulatory signal for other CD4+ T cell clones. Binding studies using CD28-Ig and CTLA-4-Ig fusion proteins demonstrate that CD86 expressed on T cells has significantly reduced binding affinity for CTLA-4 and no detectable binding to CD28. Biochemical analysis demonstrates that post-translational modifications of CD86 in human T cells are different from those of CD86-transfected Chinese hamster ovary cells or EBV-transformed B cells, in that T cells express a hypoglycosylated form of CD86 on the surface membrane. Thus, our results suggest that while CD86 is expressed on a number of different cell types, its costimulatory function and affinity for its ligands may be regulated by cell type-specific post-translational modifications.     

Beitr?ge zur Beurteilung des Honigs auf Grund der Fiehe'schen Reaktion

Ohne ZusammenfassungMitteilung aus dem Chemischen Untersuchungsamte der Stadt Breslau.     

Yield studies of rubberwood lumber during rough milling operations

The study evaluated the processing yield of furniture-grade rubberwood (Hevea brasiliensis) sawn lumber in rough milling operations. It was found that the average rough-milling yield was 69%. Therefore, rubberwood is not a low cost material as widely perceived since its processing yield is low.