Effects of a permanent magnetic field on 45Ca2+ ion influx in excitable and inexcitable cells and proliferative activity of rat spleen cells

When experimental animals were exposed to Permanent Magnetic Fields with magnetic induction (B = 0.2 T), the influx of 45Ca2+ ions into brain cells was activated, but the influx of 45Ca2+ ions into spleen cells was depressed. Similar effect was observed upon incubation of brain and spleen tissues in magnetized physiological solution. Incorporation of 3H-thymidine into spleen cells increased upon direct exposition to magnetic field and upon exposition of the spleen in magnetized physiological solution as well.     

Bericht über die Second European Personal Mobile Communications Conference EPMCC 97

Ohne Zusammenfassung     

Differential stimulation of interleukin-12 (IL-12) and IL-10 by live and killed Helicobacter pylori in vitro and association of IL-12 production with gamma interferon-producing T cells in the human gastric mucosa

The objective of these experiments was to examine the ability of Helicobacter pylori to stimulate interleukin-10 (IL-10) or IL-12 and select for either Th1 or Th2 cells. Gastric biopsy specimens were collected from patients who were categorized with respect to the presence of H. pylori and gastric disease as well as their age, gender, medications, and other factors. As Th1 and Th2 cells are selected by IL-12 and IL-10, respectively, biopsy specimens were screened for mRNA and protein for these cytokines. Although mRNA for IL-12 and IL-10 was detected in biopsy specimens obtained from both infected and uninfected patients, IL-12 protein predominated. Levels of IL-10 and IL-12 in gastric tissue did not change in response to infection. Moreover, gamma interferon (IFN-gamma)-producing T cells were found in both the infected and the uninfected gastric mucosa. Stimulation of peripheral blood leukocytes from either infected or uninfected donors with various concentrations of live or killed H. pylori induced immunoreactive IL-12 and IL-10. After stimulation with live H. pylori, IL-12 levels increased more than 30-fold, whereas IL-10 levels increased only 2- to 5-fold, compared to cells stimulated with medium alone. Interestingly, killed H. pylori induced significantly more IL-10 (P < 0.05) than live H. pylori, while recombinant urease only induced IL-10. These results demonstrate that live H. pylori selectively stimulates the induction of IL-12 and Th1 cells that produce IFN-gamma, whereas preparations used in oral vaccines induce more IL-10 and may favor Th2 cell responses.     

Energieoptimierung im vernetzten Eigenheim durch verteilte Wetterdienste im Internet

In this paper we introduce a LonWorks-based heating system which reads the current weather forecast of the Central Institute for Meteorology and Geodynamics (Vienna) from the Internet and, with the help of local weather data, controls the room climate in a way which saves more energy than conventional heatings. Such a heating model needs adequate information processing and controlling structures, which can be realised by concepts of decentralised “intelligence” and by fuzzy control.     

26S-ribonucleoprotein complex (26S-proteasome) directly interacts with fibrillar actin

26S-complex was purified from rat liver cells by centrifugation in sucrose gradients and ion exchange chromatography. The ability of 26S-proteasome to interact with fibrillar actin (F-actin) was examined by rapid cosidementation of these particles with F-actin in isokinetic sucrose gradients. It was shown that direct interaction occurred only at a low ATP concentration.     

Acoustically active lipospheres containing paclitaxel: a new therapeutic ultrasound contrast agent

RATIONALE AND OBJECTIVES: Paclitaxel-carrying lipospheres (MRX-552) were developed and evaluated as a new ultrasound contrast agent for chemotherapeutic drug delivery. METHODS: Paclitaxel was suspended in soybean oil and added to an aqueous suspension of phospholipids in vials. The headspace of the vials was replaced with perfluorobutane gas; the vials were sealed, and they were agitated at 4200 rpm on a shaking device. The resulting lipospheres containing paclitaxel were studied for concentration, size, acute toxicity in mice, and acoustic activity and drug release with ultrasound. Lipospheres containing sudan black dye were produced to demonstrate the acoustically active liposphere (AAL)-ultrasound release concept. RESULTS: Acoustically active lipospheres containing paclitaxel had a mean particle count of approximately 1 x 10(9) particles per mL and a mean size of 2.9 microns. Acute toxicity studies in mice showed a 10-fold reduction in toxicity for paclitaxel in AALs compared with free paclitaxel. The AALs reflected ultrasound as a contrast agent. Increasing amounts of ultrasound energy selectively ruptured the AALs and released the paclitaxel. CONCLUSIONS: Acoustically active lipospheres represent a new class of acoustically active drug delivery vehicles. Future studies will assess efficacy of AALs for ultrasound-mediated drug delivery.     

Dreiphasige Lastflußschätzung für Verteilungsnetze

A three-phase state estimation method for distribution systems is presented by means of normal equations or orthogonal transformation alternatively. Three phase models for lines and for two- and three-winding transformers are proposed. Some of these transformer models cause convergence problems due to ill conditioning of the gain matrix. Methods for overcoming these problems are discussed. The efficiency of the methods is demonstrated by means of a municipal distribution network.     

CIRED 1997: Session 2 — Störungen und Überspannungen

Ohne Zusammenfassung