The hypolipidemic effects of 1-acetyl-4-phenyl-1,2,4-triazolidine-3,5-dione in rodents

1-Acetyl-4-phenyl-1,2,4-triazolidine,5-dione (APTD), a potent hypolipidemic agent, lowered both serum cholesterol and triglyceride levels in normo- and hyperlipidemic rats at 10 or 20 mg/kg/day. The agent effectively lowered VLDL-cholesterol (VLDL-C) and LDL-C content and raised HDL-C content in normal and hyperlipidemic rats treated from 4 to 8 weeks. Similar effects on the incorporation of cholesterol into the lipoprotein fractions were observed after drug treatment. Tissue lipids, e.g. cholesterol, were lowered, whereas fecal cholesterol levels were increased. APTD's primary targets were acyl CoA cholesterol acyl transferase (ACAT) for cholesterol ester synthesis and sn-glycerol-3-phosphate acyl transferase (GPAT) and phosphatidylate phosphohydrolase (PPH) for triglyceride synthesis.     

Einfluß Von Mittelbeanspruchungen auf das Wechselverformungsverhalten and die verformungsinduzierte Martensitbildung des Stahls X6CrNiTi1810

Influence of mean stresses and mean strains on the cyclic deformation behavior and the plasticity-induced martensite formation of X6CrNiTi1810 stainless steel This paper describes some aspects of the fatigue behavior of the metastable austenitic stainless steel X6CrNiTi1810 (German material number 1.4541). The aim of the present investigation is to determine the influence of plasticity-induced martensite formation on the cyclic deformation behaviour at room temperature and T = 300°C. Several specimen batches were tested under stress and total strain control with different R-values, a frequency of 5 Hz and triangular load-time functions, s?-hysteresis and nondestructive magnetic measurements are used to characterize the fatigue behavior. Characteristic results are presented and discussed.     

N-Type calcium channels in the developing rat hippocampus: subunit, complex, and regional expression

The expression of multiple classes of voltage-dependent calcium channels (VDCCs) allows neurons to tailor calcium signaling to functionally discrete cellular regions. In the developing hippocampus a central issue is whether the expression of VDCC subtypes plays a role in key phases such as migration and synaptogenesis. Using radioligand binding and immunoblotting, we show that some N-type VDCCs exist before birth, consistent with a role in migration; however, most N-VDCC subunit expression is postnatal, coinciding with synaptogenesis. Immunoprecipitation studies indicate that the increased expression of N-VDCCs in early development occurs without subunit switching because there is no change in the fraction of beta3 subunits in the N-VDCC alpha1B-beta3 heteromers. Fluorescence imaging of cell surface N-VDCCs during this period reveals that N-VDCCs are expressed on somata before dendrites and that this expression is asynchronous between different subfields of the hippocampus (CA3-CA4 before CA1-CA2 and dentate gyrus). Our data argue that N-VDCC expression is an important cue in the genesis of synaptic transmission in discrete hippocampal subfields.     

Development of Detonation Flame Sprayed Cu-Base Coatings Containing Large Ceramic Particles

Metal-matrix composites (MMCs) containing large ceramic particles as superabrasives are typically used for grinding stone, minerals, and concrete. Sintering and brazing are the key manufacturing technologies for grinding tool production. However, restricted geometry flexibility and the absence of repair possibilities for damaged tool surfaces, as well as difficulties of controlling material interfaces, are the main weaknesses of these production processes. Thermal spraying offers the possibility to avoid these restrictions. The research for this paper investigated a fabrication method based on the use of detonation flame spraying technology to bond large superabrasive particles (150-600 μm, needed for grinding minerals and stones) in a metallic matrix. Layer morphology and bonding quality are evaluated with respect to superabrasive material, geometry, spraying, and powder-injection parameters. The influence of process temperature and the possibilities of thermal treatment of MMC layers are analyzed. This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain Montavon, Ed., ASM International, Materials Park, OH, 2007.     

Symptomatic gastroesophageal reflux: incidence and precipitating factors

The incidence and precipitating factors associated with symptomatic gastroesophageal reflux were evaluated by a questionnaire in 446 hospitalized and 558 nonhospitalized subjects. Of 385 control subjects 7% experienced heartburn daily, 14% noted heartburn weekly, and 15% experienced it once a month, giving a total of 36% of subjects having heartburn at least monthly. Daily heartburn occurred at a significantly greater (P less than 0.05) rate for 246 medical inpatients (14%) and for 121 patients seen in outpatient gastroenterological clinic (15%). Pregnant women seen in uncomplicated obstetrical clinic had symptoms of significantly greater (P less than 0.01) incidence: daily (25%) and at least once monthly (52%). Age, sex, or hospitalization did not significantly affect incidence. Fried foods, "spicy" foods, and alcohol were the most common precipitating factors.     

Hypolipidemic activity of 6-alkoxycarbonyl-3-aryl-1,3,5- triazabicyclo[3.1.0]hexane-2,4-diones and 2-alkoxycarbonyl-5-aryl-1,3,5-triazine-4,6(1H,5H)-diones in rodents

In continuation of previous work on macrophage activation by a Mycoplasma fermentans-derived product, originally named "mycoplasma-derived high mol. wt. material" (MDHM), we have investigated whether MDHM was capable of inducing synthesis of the reactive nitrogen intermediate nitric oxide (NO), thus rendering macrophages cytocidal. Mycoplasmas were first delipidated with acetone, and MDHM activity was then extracted with 50 mM 1-O-octyl-beta-D-glucopyranoside to yield a particularly active new preparation of MDHM which we have named MDHM-D (D for detergent). In combination with IFN-gamma, MDHM-D activated macrophages to produce reactive nitrogen intermediates and kill P815 mastocytoma cells in co-culture. P815 target cells were chosen because they are TNF-resistant. Macrophages from the LPS-low responder strain C3H/HeJ were used to minimize interference from possible LPS contamination. MDHM-D activity in this system was strictly IFN-gamma-dependent. In the presence of 25 U/ml IFN-gamma MDHM-D gave a half maximal response at a dilution of 1/100,000, showing a parallel concentration dependency for nitrite production and cytocidal activity.