An effect of Ca2+ on the Intrinsic Cl(-)-conductance of rat kidney cortex brush border membrane vesicles

Monoclonal murine anti-pesticide antibodies were produced by in vitro immunisation (IVI) of cultured splenocytes with the pesticides sulcofuron and flucofuron. The majority of both anti-flucofuron and anti-sulcofuron antibodies obtained were of the IgM isotype, rather than IgG. When used in an indirect enzyme-linked immunosorbent assay (ELISA), the antibodies bound to plate coating antigens which incorporated haptens that mimicked moieties present within the immunising pesticide. The antibodies exhibited a high degree of specificity, with the degree of cross-reactivity related to the structural similarity between the hapten present in the plate coating antigen and the moieties present within the immunising pesticide. These results indicated that antibodies specific to both sulcofuron and flucofuron had been produced by IVI. Synthesis of both hapten analogues and immunogens as required for methods based on in vivo immunisation was avoided, whilst antibody production was also comparatively more rapid than traditional methods and minimised animal discomfort.     

Phenotypic analysis of donor cells infiltrating the small intestinal epithelium and spleen during graft-versus-host disease

A pyriform sinus fistula can cause acute thyroiditis or recurrent infection in the neck. This fistula is believed to be a remnant of the branchial apparatus, although its origin has yet to be pinpointed. The spatial distribution of C cells in the thyroid gland was mapped by immunohistologic method in four patients with a pyriform sinus fistula. The C cells were identified immunohistologically with anticalcitonin antibody. The stained calcitonin-positive cells also crossreacted with the antibodies to carcinoembryonic antigen, chromogranin A, and neuron-specific enolase. The C cells were mainly distributed near the end of the fistula, and in three patients their concentration per unit volume of thyroid tissue was found to be inversely proportional to the distance from the end of the fistulas. Comparison of distant locations of the left-sided thyroid lobe in patients and the same region in control subjects showed a similar number of C cells. Thus this limited distribution of C cells suggested that the pyriform sinus fistula was either a remnant of the ultimobranchial body, the result of disturbed migration of the C cell in the fetus, or both.     

A comparison of light spot hydrophone and fiber optic probe hydrophone for lithotripter field characterization

The performance of a newly developed light spot hydrophone (LSHD) in lithotripter field characterization was compared to that of the fiber optic probe hydrophone (FOPH). Pressure waveforms produced by a stable electromagnetic shock wave source were measured by the LSHD and FOPH under identical experimental conditions. In the low energy regime, focus and field acoustic parameters matched well between the two hydrophones. At clinically relevant high energy settings for shock wave lithotripsy, the measured leading compressive pressure waveforms matched closely with each other. However, the LSHD recorded slightly larger |P_| (p < 0.05) and secondary peak compressive pressures (p < 0.01) than the FOPH, leading to about 20% increase in total acoustic pulse energy calculated in a 6 mm radius around the focus (p = 0.06). Tensile pulse durations deviated ~5% (p < 0.01) due to tensile wave shortening from cavitation activity using the LSHD. Intermittent compression spikes and laser light reflection artifacts have been correlated to bubble activity based on simultaneous high-speed imaging analysis. Altogether, both hydrophones are adequate for lithotripter field characterization as specified by the international standard IEC 61846.     

Hydrodynamic analysis of calenderable PVC and ABS compounds

Calendering of rigid and semirigid PVC (and ABS) compounds require an understanding of compound rheology and critical processing parameters. Compound rheology is modified with processing aids and lubricants. The choice of processing aid can be critical to achieving the desired rheology needed for calendering. This paper will focus on defining calendering rheology parameters as a function of a super high molecular weight MMA/SAN copolymer processing aid. These rheology parameters will be defined in terms of mill roll gap pressure, adhesive force (compound roll release) melt temperature, and shear rate. The ability to measure these parameters via a computerized two roll mill and relate this data to the actual calendering line will also be discussed.     

Angiotensin-I-converting enzyme inhibitory activity and bitterness of enzymatically-produced hydrolysates of shrimp (Pandalopsis dispar) processing byproducts investigated by Taguchi design

The importance of water-to-substrate ratio, protease type, percent enzyme and incubation time on hydrolysates produced from shrimp processing byproducts was investigated using Taguchi’s L₁₆ (4⁵) experimental design. Protease type significantly (p < 0.05) influenced soluble yield, degree of hydrolysis (DH), angiotensin-I-converting enzyme (ACE) inhibitory activity and bitterness of hydrolysates, while percent enzyme only affected the DH. Hydrolysates produced by Alcalase and Protamex possessed strong ACE inhibitory activity (IC₅₀ = 100–200 μg/ml and 70 μg/ml, respectively), accompanied by high yield, high DH and strong bitterness. Furthermore, ACE inhibition was positively correlated (r² = 0.87) with bitterness of the hydrolysates. Fractionation by size-exclusion chromatography revealed that the bitter substances, which also showed strong ACE inhibition, were <3 kDa in size and contained many hydrophobic residues, including Tyr, Phe, Leu, Ile, Val and Lys. Despite the bitterness, these hydrolysates may have potential health benefits, arising from their potent ACE inhibitory activity.     

Release of reduced inorganic selenium species into waters by the green fresh water algae Chlorella vulgaris

The common green fresh water algae Chlorella vulgaris was exposed to starting concentrations of 10 μg/L selenium in the form of selenate, selenite, or selenocyanate (SeCN(-)) for nine days in 10% Bold's basal medium. Uptake of selenate was more pronounced than that of selenite, and there was very little uptake of selenocyanate. Upon uptake of selenate, significant quantities of selenite and selenocyanate were produced by the algae and released back into the growth medium; no selenocyanate was released after selenite uptake. Release of the reduced metabolites after selenate exposure appeared to coincide with increasing esterase activity in solution, indicating that cell death (lysis) was the primary emission pathway. This is the first observation of biotic formation of selenocyanate and its release into waters from a nonindustrial source. The potential environmental implications of this laboratory observation are discussed with respect to the fate of selenium in impacted aquatic systems, the ecotoxicology of selenium bioaccumulation, and the interpretation of environmental selenium speciation data generated, using methods incapable of positively identifying reduced inorganic selenium species, such as selenocyanate.     

Effects of extraction temperature on the phenolic and parthenolide contents,and colour of aqueous feverfew (Tanacetum parthenium) extracts

The aim of this study was to determine the effects of extraction temperature on the colour as well as on the phenolic and parthenolide content of feverfew (Tanacetum parthenium) aqueous extracts, with a view to incorporating the extracts into a beverage. Results showed that extraction temperatures of 20–70 °C yielded dark-coloured extracts with low total phenol and a relatively high total tannin concentration. However, increasing the temperature to 75 °C produced lighter-coloured extracts with a significantly higher concentration of total phenols, lower total tannin fraction and maximum extraction of parthenolide. Higher extraction temperatures (80–100 °C) yielded suitably pale extracts rich in total phenols, but with progressively higher total tannin to non-tannin ratio and lower parthenolide content. The compromise temperature of 80 °C was found to provide extracts rich in parthenolide content, phenolic content and with a desirable colour, suitable for incorporation into a functional beverage.     

Assessment of Cell Disruption and Carotenoids Extraction from Sporidiobolus salmonicolor (CBS 2636)

The increasing demand for carotenoids by industries has drawn attention to their bio-production. Since pigments are intracellular, extraction steps are then needed after cell cultivation. In this work, different strategies for extraction of carotenoid pigments from Sporidiobolus salmonicolor (CBS 2636) were studied. Different solvents (dimethyl sulfoxide, petroleum ether, hexane, ethyl acetate, chloroform, and acetone), liquid N₂, and diatomaceous earth were used to disrupt the cell and thus release the intracellular carotenoids. The results of this study showed that when multiple solvents were used, a synergistic effect on the extent of carotenoids recovery was obtained. Maximum concentration of total carotenoids (913 μg/L) was obtained in the treatment using liquid N₂ and dimethyl sulfoxide to disrupt the cell, followed by the extraction with a solution of acetone/methanol (7:3, v/v).