DETERMINATION OF GUSTATORY SUCROSE THRESHOLD IN WATER BY USE OF A LINEAR SUCROSE GRADIENT

A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).     

Myeloperoxidase-catalyzed iodination and coupling.

Myeloperoxidase (MPO), which displays considerable amino acid sequence homology with thyroid peroxidase (TPO) and lactoperoxidase (LPO), was tested for its ability to catalyze iodination of thyroglobulin and coupling of two diiodotyrosyl residues within thyroglobulin to form thyroxine. After 1 min of incubation in a system containing goiter thyroglobulin, I-, and H2O2, the pH optimum of MPO-catalyzed iodination was markedly acidic (approximately 4.0), compared to LPO (approximately 5.4) and TPO (approximately 6.6). The presence of 0.1 N Cl- or Br- shifted the pH optimum for MPO to about 5.4 but had little or no effect on TPO- or LPO-catalyzed iodination. At pH 5.4, 0.1 N Cl- and 0.1 N Br- had a marked stimulatory effect on MPO-catalyzed iodination. At pH 4.0, however, iodinating activity of MPO was almost completely inhibited by 0.1 N Cl- or Br-. Inhibition of chlorinating activity of MPO by Cl- at pH 4.0 has been previously described. When iodination of goiter thyroglobulin was performed with MPO plus the H2O2 generating system, glucose-glucose oxidase, at pH 7.0, the iodinating activity was markedly increased by 0.1 N Cl-. Under these conditions iodination and thyroxine formation were comparable to values observed with TPO. MPO and TPO were also compared for coupling activity in a system that measures coupling of diiodotyrosyl residues in thyroglobulin in the absence of iodination. MPO displayed very significant coupling activity, and, like TPO, this activity was stimulated by a low concentration of free diiodotyrosine (1 microM). The thioureylene drugs, propylthiouracil and methimazole, inhibited MPO-catalyzed iodination both reversibly and irreversibly, in a manner similar to that previously described for TPO-catalyzed iodination.     

Effect of neurotensin on pancreatic function in man

The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.     

Delimitation of the maritime boundary in the gulf of Maine area

The compulsory dispute settlement regime included in the 1982 Law of the Sea Convention is recognized as one of the most comprehensive in a modern international convention. Yet, in the recent application of this regime, the question has arisen as to whether the procedural prerequisites associated with the LOS Convention's compulsory dispute settlement mechanism are so arduous as to avoid binding and compulsory jurisdiction in most instances. This article addresses that question by examining, in particular, the reasoning of the Southern Bluefin Tuna arbitration tribunal, which found Article 281 of Section 1 of the LOS Convention to bar jurisdiction to the compulsory dispute settlement mechanism prescribed by the Convention, and offers suggestions as to how states might distinguish or overcome the barriers imposed by the Southern Bluefin Tuna tribunal in future cases.     

CD8 alpha beta T cells are not essential to the pathogenesis of arthritis or colitis in HLA-B27 transgenic rats

The class I MHC allele HLA-B27 is highly associated with the human spondyloarthropathies, but the basis for this association remains poorly understood. Transgenic rats with high expression of HLA-B27 develop a multisystem inflammatory disease that includes arthritis and colitis. To investigate whether CD8alphabeta T cells are needed in this disease, we depleted these cells in B27 transgenic rats before the onset of disease by adult thymectomy plus short-term anti-CD8alpha mAb treatment. This treatment induced profound, sustained depletion of CD8alphabeta T cells, but failed to suppress either colitis or arthritis. To address the role of CD8alpha(+)beta(-) cells, we studied four additional groups of B27 transgenic rats treated with: 1) continuous anti-CD8alpha mAb, 2) continuous isotype-matched control mAb, 3) the thymectomy/pulse anti-CD8alpha regimen, or 4) no treatment. Arthritis occurred in approximately 40% of each group, but was most significantly reduced in severity in the anti-CD8alpha-treated group. In addition to CD8alphabeta T cells, two sizeable CD8alpha(+)beta(-) non-T cell populations were also reduced by the anti-CD8alpha treatment: 1) NK cells, and 2) a CD4(+)CD8(+)CD11b/c(+)CD161a(+)CD172a(+) monocyte population that became expanded in diseased B27 transgenic rats. These data indicate that HLA-B27-retricted CD8(+) T cells are unlikely to serve as effector cells in the transgenic rat model of HLA-B27-associated disease, in opposition to a commonly invoked hypothesis concerning the role of B27 in the spondyloarthropathies. The data also suggest that one or more populations of CD8alpha(+)beta(-) non-T cells may play a role in the arthritis that occurs in these rats.     

HLA-B27 in transgenic rats forms disulfide-linked heavy chain oligomers and multimers that bind to the chaperone BiP

To test the hypothesis that HLA-B27 predisposes to disease by forming disulfide-linked homodimers, we examined rats transgenic for HLA-B27, mutant Cys(67)Ser HLA-B27, or HLA-B7. In splenic Con A blasts from high transgene copy B27 lines that develop inflammatory disease, the anti-H chain mAb HC10 precipitated four bands of molecular mass 78-105 kDa and additional higher molecular mass material, seen by nonreducing SDS-PAGE. Upon reduction, all except one 78-kDa band resolved to 44 kDa, the size of the H chain monomer. The 78-kDa band was found to be BiP/Grp78, and the other high molecular mass material was identified as B27 H chain. Analysis of a disease-resistant low copy B27 line showed qualitatively similar high molecular mass bands that were less abundant relative to H chain monomer. Disease-prone rats with a Cys(67)Ser B27 mutant showed B27 H chain bands at 95 and 115 kDa and a BiP band at 78 kDa, whereas only scant high molecular mass bands were found in cells from control HLA-B7 rats. (125)I-surface labeled B27 oligomers were immunoprecipitated with HC10, but not with a mAb to folded B27-beta(2)-microglobulin-peptide complexes. Immunoprecipitation of BiP with anti-BiP Abs coprecipitated B27 H chain multimers. Folding and maturation of B27 were slow compared with B7. These data indicate that disulfide-linked intracellular H chain complexes are more prone to form and bind BiP in disease-prone wild-type B27 and B27-C67S rats than in disease-resistant HLA-B7 rats. The data support the hypothesis that accumulation of misfolded B27 participates in the pathogenesis of B27-associated disease.     

A spatial analytical approach for selecting reintroduction sites for burbot in English rivers

1. Availability of suitable habitat is a prerequisite for species reintroduction success, and to ensure population persistence, investigations of a species’ habitat utilisation throughout its life history should be conducted as part of a feasibility study. 2. Habitat utilisation models for burbot, Lota lota, developed using data from field studies conducted in France and Germany and information from the literature were used to assess the feasibility of reintroducing burbot into rivers of its former native range in eastern England. 3. Per cent tree roots, aquatic vegetation and flow types were important predictors of adult burbot abundance. Furthermore, the habitat utilisation models were supplemented with information from the literature, which suggested that off‐channel habitat such as wetlands and backwaters is important for spawning and nursery stages. 4. An assessment of the habitat availability in the rivers of the burbot’s former native range using variables related to spawning and nursery and adult life stages showed that although adult habitat was widely distributed, the availability of spawning and nursery habitat was less abundant, potentially limiting successful reestablishment. 5. Potential suitable habitat was concentrated in the central and southern areas of the species’ former English distribution. Overall, rivers of the burbot’s former range potentially afford suitable habitat to sustain a reintroduced population. However, sites should be preferentially selected on the basis of having appropriate spawning and nursery areas.     

Long-term platinum retention after treatment with cisplatin and oxaliplatin

Background  

The aim of this study was to evaluate long-term platinum retention in patients treated with cisplatin and oxaliplatin.