Animal Suffering: Representations and the Act of Looking

Animal advocacy uses images of nonhuman suffering as a form of normative rhetoric and a method of persuasion. Although much attention has been given to various facets of the depiction of human suffering, images of animal suffering have, to a large extent, escaped closer scrutiny. This paper seeks to remedy the situation by investigating four issues—the risk of aesthetics, the risk of perpetuating moral wrongs, the problem of privacy, and compassion fatigue—as they relate to images of farmed animal suffering. The paper will argue that images of nonhuman suffering are in danger of being interpreted as a form of visual intrigue, and that they invite seldom-asked questions concerning the justification of the act of looking, together with the privacy of nonhuman animals. Moreover, it will be maintained that compassion fatigue commonly affects how these images are perceived. Making use of the views of Susan Sontag, J. M. Coetzee, and Stanley Cohen (among others), it will be argued that, in order to escape the problematic connotations and consequences of the aforementioned issues, a normative dimension pointing toward action must be explicated.     

Nitrate respiration and diel migration patterns of diatoms are linked in sediments underneath a microbial mat

Diatoms are among the few eukaryotes known to store nitrate (NO₃⁻) and to use it as an electron acceptor for respiration in the absence of light and O₂. Using microscopy and ¹⁵N stable isotope incubations, we studied the relationship between dissimilatory nitrate/nitrite reduction to ammonium (DNRA) and diel vertical migration of diatoms in phototrophic microbial mats and the underlying sediment of a sinkhole in Lake Huron (USA). We found that the diatoms rapidly accumulated NO₃⁻ at the mat-water interface in the afternoon and 40% of the population migrated deep into the sediment, where they were exposed to dark and anoxic conditions for ~75% of the day. The vertical distribution of DNRA rates and diatom abundance maxima coincided, suggesting that DNRA was the main energy generating metabolism of the diatom population. We conclude that the illuminated redox-dynamic ecosystem selects for migratory diatoms that can store nitrate for respiration in the absence of light. A major implication of this study is that the dominance of DNRA over denitrification is not explained by kinetics or thermodynamics. Rather, the dynamic conditions select for migratory diatoms that perform DNRA and can outcompete sessile denitrifiers.     

D-Ala2]-Deltorphin I peptoid and retropeptoid analogues: synthesis, biological activity and conformational investigations.

The synthesis is described of a [D-Ala2]-deltorphin I peptoid analogue in which all amino acid residues have been substituted by the corresponding N-alkylglycine residues. The [D-Ala2]-deltorphin I retropeptoid was also prepared as well as [Ala1 ,D-Ala2]-deltorphin 1 and the corresponding peptoid. Structural investigations by FT-IR and fluorescence measurements were carried out on the synthetic analogues and on some [D-Ala2]-deltorphin 1 peptide-peptoid hybrids previously prepared. According to the fluorescence measurements the distance between the aromatic residues in the deltorphin I peptoid and retropeptoid is similar to that suggested for the delta- and micro-opioids, respectively. Measurements of CD in the presence of beta-cyclodextrin, and some preliminary pharmacological experiments were also performed. No dichroic bands are present in the spectrum of the [Ntyr1,D-Ala2]-deltorphin I, but an increasing dichroic effect appears in the spectra of both the deltorphin I peptoid and retropeptoid. Activity tests on isolated organ preparations showed that the modifications made produced a dramatic decrease in the agonistic activity of the synthetic derivatives.     

New mammalian cellular systems to study mutations introduced at the break site by non-homologous end-joining

The non-homologous end-joining (NHEJ) pathway is a mechanism to repair DNA double strand breaks, which can introduce mutations at repair sites. We constructed new cellular systems to specifically analyze sequence modifications occurring at the repair site. In particular, we looked for the presence of telomeric repeats at the repair junctions, since our previous work indicated that telomeric sequences could be inserted at break sites in germ-line cells during primate evolution. To induce specific DNA breaks, we used the I-SceI system of Saccharomyces cerevisiae or digestion with restriction enzymes. We isolated human and hamster cell lines containing the I-SceI target site integrated in a single chromosomal locus and we exposed the cells to a continuous expression of the I-SceI endonuclease gene. Additionally, we isolated human cell lines that expressed constitutively the I-SceI endonuclease and we introduced the target site on an episomal plasmid stably transfected into the cells. These strategies allowed us to recover repair junctions in which the I-SceI target site was modified at high frequency (100% in hamster cells and about 70% in human cells). Finally, we analyzed junctions produced on an episomal plasmid linearized by restriction enzymes. In all the systems studied, sequence analysis of individual repair junctions showed that deletions were the most frequent modifications, being present in more than 80% of the junctions. On the episomal plasmids, the average deletion length was greater than at intrachromosomal sites. Insertions of nucleotides or deletions associated with insertions were rare events. Junction organization suggested different mechanisms of formation. To check for the insertion of telomeric sequences, we screened plasmid libraries representing about 3.5 x 10(5) junctions with a telomeric repeat probe. No positive clones were detected, suggesting that the addition of telomeric sequences during double strand break repair in somatic cells in culture is either a very rare event or does not occur at all.     

Numerical approaches for quantitative analysis of two-dimensional maps: a review of commercial software and home-made systems

The present review attempts to cover a number of methods that have appeared in the last few years for performing quantitative proteome analysis. However, due to the large number of methods described for both electrophoretic and chromatographic approaches, we have limited this review to conventional two-dimensional (2-D) map analysis which couples orthogonally a charge-based step (isoelectric focusing) to a size-based separation step (sodium dodecyl sulfate-electrophoresis). The first and oldest method applied to 2-D map data reduction is based on statistical analysis performed on sets of gels via powerful software packages, such as Melanie, PDQuest, Z3 and Z4000, Phoretix and Progenesis. This method calls for separately running a number of replicas for control and treated samples. The two sets of data are then merged and compared via a number of software packages which we describe. In addition to commercially-available systems, a number of home made approaches for 2-D map comparison have been recently described and are also reviewed. They are based on fuzzyfication of the digitized 2-D gel image coupled to linear discriminant analysis, three-way principal component analysis or a combination of principal component analysis and soft-independent modeling of class analogy. These statistical tools appear to perform well in differential proteomic studies.     

Characterization of electrogenic bromosulfophthalein transport in carnation petal microsomes and its inhibition by antibodies against bilitranslocase

Bilitranslocase is a rat liver plasma membrane carrier, displaying a high-affinity binding site for bilirubin. It is competitively inhibited by grape anthocyanins, including aglycones and their mono- and di-glycosylated derivatives. In plant cells, anthocyanins are synthesized in the cytoplasm and then translocated into the central vacuole, by mechanisms yet to be fully characterized. The aim of this work was to determine whether a homologue of rat liver bilitranslocase is expressed in carnation petals, where it might play a role in the membrane transport of anthocyanins. The bromosulfophthalein-based assay of rat liver bilitranslocase transport activity was implemented in subcellular membrane fractions, leading to the identification of a bromosulfophthalein carrier (K(M) = 5.3 microm), which is competitively inhibited by cyanidine 3-glucoside (Ki = 51.6 microm) and mainly noncompetitively by cyanidin (Ki = 88.3 microm). Two antisequence antibodies against bilitranslocase inhibited this carrier. In analogy to liver bilitranslocase, one antibody identified a bilirubin-binding site (Kd = 1.7 nm) in the carnation carrier. The other antibody identified a high-affinity binding site for cyanidine 3-glucoside (Kd = 1.7 microm) on the carnation carrier only, and a high-affinity bilirubin-binding site (Kd = 0.33 nm) on the liver carrier only. Immunoblots showed a putative homologue of rat liver bilitranslocase in both plasma membrane and tonoplast fractions, isolated from carnation petals. Furthermore, only epidermal cells were immunolabeled in petal sections examined by microscopy. In conclusion, carnation petals express a homologue of rat liver bilitranslocase, with a putative function in the membrane transport of secondary metabolites.     

Osteoporosis,inflammation and ageing

Osteoporosis is a condition characterized by low bone mass and increased bone fragility, putting patients at risk of fractures, which are major causes of morbidity substantially in older people. Osteoporosis is currently attributed to various endocrine, metabolic and mechanical factors. However, emerging clinical and molecular evidence suggests that inflammation also exerts significant influence on bone turnover, inducing osteoporosis. Numerous proinflammatory cytokines have been implicated in the regulation of osteoblasts and osteoclasts, and a shift towards an activated immune profile has been hypothesized as important risk factor. Chronic inflammation and the immune system remodelling characteristic of ageing, as well as of other pathological conditions commonly associated with osteoporosis, may be determinant pathogenetic factors. The present article will review the current perspectives on the interaction between bone and immune system in the elderly, providing an interpretation of osteoporosis in the light of inflamm-ageing.     

Heat-induced changes in porcine annulus fibrosus biomechanics

The intervertebral disc is implicated as the source of low-back pain in a substantial number of patients. Because thermal therapy has been thought to have a therapeutic effect on collagenous tissues, this technique has recently been incorporated into several minimally invasive back pain treatments. However, patient selection criteria and precise definition of optimum dose are hindered by uncertainty of treatment mechanisms. The purpose of this study was to quantify acute changes in annulus fibrosus biomechanics after a range of thermal exposures, and to correlate these results with tissue denaturation. Intact annulus fibrosus (attached to adjacent vertebrae) from porcine lumbar spines was tested ex vivo. Biomechanical behavior, microstructure, peak of denaturation endotherm, and enthalpy of denaturation (mDSC) were determined before and after hydrothermal heat treatment at 37 degrees C, 50 degrees C, 60 degrees C, 65 degrees C, 70 degrees C, 75 degrees C, 80 degrees C, and 85 degrees C. Shrinkage of excised annular tissue (removed from adjacent vertebrae) was also measured after treatment at 85 degrees C. Significant differences in intact annulus biomechanics were observed after treatment, but the effects were much smaller in magnitude than those observed in excised annulus and those reported previously for other tissues. Consistent with this, intact tissue was only minimally denatured by treatment at 85 degrees C for 15 min, whereas excised tissue was completely denatured by this protocol. Our data suggest that in situ constraint imposed by the joint structure significantly retards annular thermal denaturation. These findings should aid the interpretation of clinical outcomes and provide a basis for the future design of optimum dosing regimens.     

Molecular determinants regulating the pairing of NKG2 molecules with CD94 for cell surface heterodimer expression

The lytic capacity of a NK cell is regulated, in part, by the balance in cell surface expression between inhibitory CD94/NKG2A and activating CD94/NKG2C heterodimers. We demonstrate that, in the absence of DAP12, rhesus monkey NKG2A is preferentially expressed at the cell surface with CD94 due to a single amino acid difference in the transmembrane of NKG2A and NKG2C. Furthermore, in the context of an NKG2A transmembrane, the stalk domain of NKG2C was found to enhance heterodimer formation with CD94 compared with the stalk domain of NKG2A. In the presence of DAP12, the ability of NKG2C to compete for cell surface CD94 heterodimerization is enhanced and approaches that of NKG2A. Finally, allelic differences that affect the ability of rhesus NKG2A to reach the cell surface with CD94 could also be mapped to the transmembrane. These differences in the ability of inhibitory and activating NKG2 molecules to reach the cell surface provide a mechanism for the regulation of NK cell activity.