Perception of posture and cerebral blood flow.

The perception of posture in man is made possible by the information of the vestibular organs, the visual system, the proprioception and the blood volume distribution. The present study examined the cerebral blood flow velocity (CBFV) and the fluid volume of the thoracic cavity under different pressure conditions and their effects on the perception of posture. Changes in blood flow velocity were measured by transcranial Doppler sonography (TCD), and changes in the blood volume distribution of the upper torso were registered by impedance plethysmography. The results indicated that the cerebral blood flow volume and the thoracic blood volume changed in the same manner. Lower Body Positive Pressure (+30 mmHg) led to an increase in central volume and CBFV. During the Lower Body Negative Pressure Treatment (-30 mmHg), the central blood volume and the cerebral blood flow velocity decreased while venous pooling occurred. Additionally, the changes in both parameters were associated with an altered posture perception. The correlations between the SHP and the two physiological parameters cerebral blood flow velocity and fluid shift in the upper thorax indicate that the fluid shift in the thoracic cavity was more closely related to the SHP than to the changes in cerebral blood volume.

[The care dependency scale, an assessment instrument]. / Die Pflegeabhängigkeitsskala, eine methodologische Studie.

The Care Dependency Scale, an instrument for the assessment of patients'care dependency, has been translated into German. The scale was tested on (inter-) rater reliability and criterion and construct validity in a hospital population on geriatric, surgical and paediatric wards. As the results of this study were very satisfying, positive recommendations regarding the suitability of the scale for use in the German nursing care situation could be made. However further psychometric testing of the scale is important, for instance in other populations. A final conclusion is that the scale may be used in care settings in German-speaking countries.

Isoforms of an N-acetyl-beta-D-glucosaminidase from the Antarctic krill, Euphausia superba: purification and antibody production.

Two forms of the chitinolytic enzyme N-acetyl-beta-D-glucosaminidase (NAGase, EC 3.2.1.52) have been isolated from the Antarctic krill, Euphausia superba, in order to study their potential role in temperature adaptation processes. A chromatographic protocol was developed that allowed complete separation of the two enzyme forms, named NAGase B and NAGase C. The latter was purified to homogeneity with 600-fold enrichment and a yield of 17%. The molecular mass was 150 kDa. NAGase B showed characteristics of a glycoprotein due to affinity towards concanavalin A sepharose, while NAGase C did not. Highly specific polyclonal antibodies to NAGase C [anti-(E. superba-NAGase C)-IgG] showed only negligible cross-reactivity with NAGase B isoforms. A comparison with the Northern krill, Meganyctiphanes norvegica, revealed a corresponding chromatographic pattern with two main activity peaks, for differentiation named NAGase II and NAGase III. Application of the antibody on M. norvegica revealed a high specificity toward NAGase III and a low cross-reactivity with NAGase II. First indication is given that the two forms are no isoenzymes in a strict sense but instead may have different functions in the metabolism of krill.

Determination of alpha-, gamma(+ beta)-, and delta-tocopherols in a variety of liver tissues by reverse-phase high pressure liquid chromatography.

A modified version of a previously published extraction technique using acetone as the extracting medium and separation on an HPLC equipped with a Spherisorb C18 ODS2 column packed with 3 micron particles along with a suitable flow rate and mobile phase significantly improves the resolution of the chromatographic output (fluorescence detector), allowing for accurate measurement of alpha-, delta- and gamma(+ beta)-tocopherols. It was found that two extractions of the same sample yielded approximately 97% of the total extractable alpha-tocopherol. Vitamin C was not needed as an anti-oxidant to protect alpha-tocopherol during extraction from chicken liver but was needed when using fish liver. alpha-tocopherol was found not to be evenly distributed in beef, chicken or fish liver.