Characterization of the reactivity of riverine heterogeneous sediments using a facies-based approach; the Rhine-Meuse delta (The Netherlands)

Large groundwater resources are found in densely populated lowland areas, which consist often of young unconsolidated and reduced sediments. When anthropogenic activities lead to oxygenation of the aquifer, breakdown of the main reduced fractions, i.e. sedimentary organic matter (SOM) and pyrite, could lead to severe groundwater deterioration...

60 GHz GaAs MMIC mixers with integrated LO buffer

Using the 0.15 um GaAs mHEMT process from WIN semiconductors, two 60 GHz down-conversion mixers have been designed, processed and measured. Both designs include a LO buffer amplifier to allow for a reduced external LO power level. With an LO power of +10 dBm, the measured RF input match is better than -15 dB at 60 GHz and the conversion loss is...

Induction of advanced glycation end products and alterations of the tensile properties of articular cartilage

Objective. To determine whether increasing advanced glycation end products (AGEs) in bovine articular cartilage to levels present in aged human cartilage modulates the tensile biomechanical properties of the tissue. Methods. Adult bovine articular cartilage samples were incubated in a buffer solution with ribose to induce the formation of AGEs...

Influence of inflammatory cells and serum on the performance of implantable glucose sensors

The objective of this investigation was to evaluate the influence of polymorphonuclear granulocytes on the performance of uncoated and cellulose acetate/Nafion® coated amperometric glucose sensors in vitro. The response of these sensors was also investigated in serum. Uncoated and coated sensors showed lower sensitivities to glucose, with a...

Poly(3,4-ethylenedioxythiophene)-based glucose biosensors

Amperometric biosensors for the recognition of glucose oxidase (GOx) based on poly(3,4-ethylenedioxythiophene) (PEDOT) were fabricated for the first time. The resulting biosensor has potential applications for long-term glucose measurements.

Intercellular communication and cell proliferation in precision-cut rat liver slices: Effect of medium composition and DDT

Gap junctional intercellular communication (GJIC) and cell proliferation were studied in control and 1,1'-bis(p-chlorophenyl)-2,2,2,-trichloroethane (DDT) treated precision-cut liver slices of rat by evaluating connexin 32 (Cx32) expression and 5-bromo-2'-deoxyuridine (BrdU) incorporation. In addition, the effect of different culture media (RPMI...

The effect of storage of whole potatoes of three cultivars on the patatin and protease inhibitor content; a study using capillary electrophoresis and MALDI-TOF mass spectrometry

The content and biological activity of patatin and the protease inhibitors of molecular size 20-22 kDa present in whole potato tubers were investigated as a function of storage time. The amount of buffer-extractable protein decreased gradually during storage of whole potatoes of the cultivars Bintje and Desiree for 47 weeks whereas, for Elkana,...

Clot accumulation characteristics of plasminogen-bearing liposomes in a flow-system

In this study, the clot accumulation properties of liposome-coupled plasminogen were compared to those of free (non-liposomal) plasminogen in an in vitro, closed-loop, flow-system. After introduction of a clot into the closed system, double-radiolabelled plasminogen-liposomes were administered and the accumulation of radiolabel on the entire...

The interaction of the anti-cancer drug cisplatin with phospholipids is specific for negatively charged phospholipids and takes place at low chloride ion concentration

The interaction of the anti-cancer drug cis-diamminedichloroplatinum(II) (cisPt) with model membranes was studied, with emphasis on the cisPt and phospholipid species involved. Binding studies using large unilamellar vesicles have revealed that: (i) Interaction involved negatively charged phospholipids only, and (ii) Interaction with negatively...

Interlaboratory comparison of microsomal ethoxyresorufin and pentoxyresorufin O-dealkylation determinations: standardization of assay conditions

Assay conditions and results of cytochrome P-450 dependent 7-ethoxyresorufin (ER) and 7-pentoxyresorufin (PR) O-dealkylation (OD) by rat liver microsomes were compared by four laboratories in the Netherlands. Microsomal mixtures were prepared from control, 3-methylcholanthrene and phenobarbital pretreated animals, resulting in different levels...

Distribution of tissue-type plasminogen activator (activity and antigen) in rat tissues.

Tissue-type plasminogen activator (PA) activity and antigen was measured in nine different tissues from healthy rats (brain, lung, heart, liver, spleen, kidney, adrenal, aorta and skeletal muscle). After extraction in a KSCN buffer (for kidney) or in an acid acetate buffer (for all other tissues), total PA activity was determined by an improved...

The colorimetric determination of cyanide in human food and animal feed

The well-known Kroller method for the determination of cyanide requires the use of the harmful chemicals benzidine (carcinogenic) and bromine (toxic) in the colorimetric part; the analytical result depends strongly on the conduct of the liberation procedure. The substitution of barbituric acid and N-chlorosuccinimide for benzidine and bromine...

Thermal inactivation of bacteriophage _X174 and two of its mutants

The thermal inactivation of the two forms (∅* and ∅) of bacteriophage ∅X174 with different adsorption properties was investigated under various conditions of pH, ionic strength, and temperature. A reaction mechanism is proposed that is similar for both forms. At high temperatures inactivation occurs mainly as a result of protein destruction and...

The transition between two forms of bacteriophage φX17A differing in heat sensitivity and adsorption characteristics

If cells of the bacterium Escherichia coliC infected with bacteriophage φX174 are lysed artificially in the cold, the phage obtained is relatively heat resistant at temperatures around 65° and unable to adsorb to host cells at 4°. At 37° the phage particles become more thermolabile with respect to inactivation at 65° and, concomitantly, obtain...