Novel amidino substituted 2-phenylbenzothiazoles: Synthesis,antitumor evaluation in vitro and acute toxicity testing in vivo

The efficient synthesis of new bis-substituted nitro-amidino, amino-amidino (10a, 10b–13a, 13b) and previously prepared diamidino 2-phenyl-benzothiazoles (9a, 9b) is described. The compounds 11a and 11b were prepared by recently developed methodology of the key precursors in zwitterionic form 8a and 8b with 4-nitrobenzoylchloride in a very good yield (70%). All compounds except diamidino-substituted 2-phenylbenzothiazole 9a show exceptionally prominent tumor cell-growth inhibitory activity and cytotoxicity, whereby the special selectivity of amino-amidine 2-phenylbenzothiazole 12a towards MCF-7 and H 460 cells makes this compound a prospective lead compound that should be further evaluated in animal models. All in vivo tested compounds (12a, 12b, 13a and 13b) are absorbed from mice gastrointestinal system. LD₅₀ are between 67.33 and 696.2 mg/kg body weight (OECD/EPA toxicity categories 2–3).     

Imaging cell interactions with native and crosslinked polyelectrolyte multilayers

The adhesion of primary chondrocytes to polyelectrolyte multilayer films, made of poly(l-lysine) (PLL) and hyaluronan (HA), was investigated for native and crosslinked films, either ending by PLL or HA. Crosslinking the film was achieved by means of a water-soluble carbodiimide in combination with N-hydroxysulfosuccinimide. The adhesion of macrophages and primary chondrocytes was investigated by microscopical techniques (optical, confocal, and atomic), providing useful information on the cell/film interface. Native films were found to be nonadhesive for the, primary chondrocytes, but could be degraded by macrophages, as could be visualized by confocal laser scanning microscopy after film labeling. Confocal microscopy images show that these films can be deformed by the condrocytes and that PLL diffuses at the chondrocyte membrane. In contrast, the cells adhered and proliferated well on the crosslinked films, which were not degraded by the macrophages. These results were confirmed by a MTT test over a 6-d period and by atomic force microscopy observations. We thus prove that chemical crosslinking can dramatically change cell adhesion properties, the cells being more stably anchored on the crosslinked films. Both authors kcontributed equally.     

Protein–Protein and Protein–Membrane Associations in the Lignin Pathway

Supramolecular organization of enzymes is proposed to orchestrate metabolic complexity and help channel intermediates in different pathways. Phenylpropanoid metabolism has to direct up to 30% of the carbon fixed by plants to the biosynthesis of lignin precursors. Effective coupling of the enzymes in the pathway thus seems to be required. Subcellular localization, mobility, protein–protein, and protein–membrane interactions of four consecutive enzymes around the main branch point leading to lignin precursors was investigated in leaf tissues of Nicotiana benthamiana and cells of Arabidopsis thaliana. CYP73A5 and CYP98A3, the two Arabidopsis cytochrome P450s (P450s) catalyzing para- and meta-hydroxylations of the phenolic ring of monolignols were found to colocalize in the endoplasmic reticulum (ER) and to form homo- and heteromers. They moved along with the fast remodeling plant ER, but their lateral diffusion on the ER surface was restricted, likely due to association with other ER proteins. The connecting soluble enzyme hydroxycinnamoyltransferase (HCT), was found partially associated with the ER. Both HCT and the 4-coumaroyl-CoA ligase relocalized closer to the membrane upon P450 expression. Fluorescence lifetime imaging microscopy supports P450 colocalization and interaction with the soluble proteins, enhanced by the expression of the partner proteins. Protein relocalization was further enhanced in tissues undergoing wound repair. CYP98A3 was the most effective in driving protein association.     

If you knew what was good for you! The value of environmental enrichments with known welfare benefits is not demonstrated by sows using operant techniques

This study assessed the motivation of gestating sows housed in standard, barren gestation stalls (used for breeding/implantation and/or gestation) for access to environmental enrichment. Enrichment consisted of a cotton rope or rubber mat in comparison to positive (additional food when fed at commercial levels) and negative (empty trough) controls. Although environmental enrichment may improve animal welfare, sows' valuation of enrichments is largely unknown. This study used an operant panel and obtained behavioral measures to quantify motivation. As indicated by a higher price paid and lower latencies to press the panel and enter the treatment stall (all comparisons, p < .05), sows demonstrated higher motivation for food compared with all treatments. Sows housed in gestation stalls did not demonstrate high motivation via operant responding for a cotton rope or a rubber mat; nor did they demonstrate any differences in behavioral measures (all comparisons, p > .10). Although sows' motivation for a mat did not differ from that for an empty trough, previous work has demonstrated the welfare benefits associated with comfort flooring.     

A note on the effects of co-mingling piglet litters on pre-weaning growth, injuries and responses to behavioural tests

The purpose of this study was to determine how co-mingling litters affected piglets’ pre-weaning growth, ear injuries, suckling behaviour and responses to behavioural tests used to measure coping abilities. Thirty sows and their respective litters were housed in standard farrowing crates until day 13 after birth. On day13, the partition between two neighbouring pens was removed for 20 litters allowing piglets to interact (forming 10 co-mingled litters). The remaining 10 control litters were kept in standard farrowing crates throughout the experiment. Three focal piglets from each litter were used for data collection. Focal piglets were weighed and ear injuries recorded on days 2, 4, 9, 12, 15 and 18 after birth. There were no differences in piglets’ weight gain before or after co-mingling. Ear injuries were more abundant in co-mingled litters on day 15 (P < 0.05) but these differences disappeared by day 18. Suckling behaviour was recorded on days 5, 8, 10, 14, 16 and 18 after birth. There were no differences in teat fidelity, suckling frequency and mother fidelity between treatments. Three behavioural tests, social challenge, isolation, and backtest, were performed before and after co-mingling. There were no treatment effects on piglets’ response to the isolation test and backtest. Co-mingled piglets showed longer latency for the first aggressive interaction (P < 0.05), spent more time in proximity to one another (P < 0.05) and performed less single bites (P < 0.05) than control piglets during the social challenge. In addition, the duration and frequency of aggressive interactions (P < 0.05) were lower in co-mingled piglets than control piglets. Co-mingling did not affect the frequency of single head thrusts or oral–nasal contact, but did tend to increase the frequency of escape attempts (P < 0.10). Our results suggest that co-mingling litters during lactation affects piglets’ social behaviour, by primarily decreasing aggressive interactions during social challenges.     

Predominance of a bacteriocin-producing Lactobacillus salivarius component of a five-strain probiotic in the porcine ileum and effects on host immune phenotype

Relative predominance of each of five probiotic strains was investigated in the ileum of weaned pigs, compared with that in feces, when administered in combination at c. 5 x 10(9) CFU day(-1) for 28 days. Probiotic was excreted at 10(6)-10(9) CFU g(-1) feces, while ileal survival ranged from 10(2) to 10(6) CFU g(-1) digesta. In contrast to the feces, where Lactobacillus murinus DPC6002 predominated, the bacteriocin-producing Lactobacillus salivarus DPC6005 dominated over coadministered strains both in the ileum digesta and in mucosa. Probiotic administration did not alter counts of culturable fecal Lactobacillus or Enterobacteriaceae but higher ileal Enterobacteriaceae were observed in the ileal digesta of probiotic-fed pigs (P<0.05). We observed decreased CD25 induction on T cells and monocytes (P<0.01) and decreased CTLA-4 induction (P<0.05) by the mitogen phytohemagglutinin on CD4 T cells from the probiotic group. Probiotic treatment also increased the proportion of CD4+ CD8+ T cells within the peripheral T-cell population and increased ileal IL-8 mRNA expression (P<0.05). In conclusion, superior ileal survival of L. salivarius compared with the other coadministered probiotics may be due to a competitive advantage conferred by its bacteriocin. The findings also suggest that the five-strain combination may function as a probiotic, at least in part, via immunomodulation.     

Assessment of skin carbonyl content as a noninvasive measure of biological age.

The oxidative modification of proteins by reactive species, especially reactive oxygen species, is implicated in the etiology or progression of a panoply of disorders and diseases. For the most part, oxidatively modified proteins are not repaired and must be removed by proteolytic degradation. The level of these modified molecules can be quantitated by measurement of the protein carbonyl content, which has been shown to increase in a variety of diseases and processes, most notably during aging. However, these studies have required invasive techniques to obtain cells for analysis. We examined the possibility that desquamating skin cells (corneocytes) would also show an age-related increase in protein carbonyl content, thus providing a noninvasive method for assessing biological age. This was not the case, as we found no age-dependent relationship in the protein carbonyl content of skin cells from volunteers aged 20 to 79 years.     

Synthesis and nuclease stability of trilysyl dendrimer-oligodeoxyribonucleotide hybrids.

Hybrids of oligonucleotides and trilysyl-dendrimers with terminal acyl groups were prepared via solid-phase synthesis, including a DNA hexamer bearing an additional 3'-appendage. These were shown to be degraded more slowly by nuclease S1 than control strands, particularly at low pH, and, in one case, to form a duplex with a complementary strand whose melting point at pH 7 was higher than that of the control duplex.