Messenger RNA levels of estrogen receptors alpha and beta and progesterone receptors in the cyclic and inseminated/early pregnant sow uterus

The aim of the present study was to investigate differences in the expression of mRNAs for ERalpha, ERbeta and PR in the sow uterus at different stages of the estrous cycle as well as in inseminated sows at estrus and during early pregnancy by use of solution hybridization and in relation to plasma levels of estradiol and progesterone. Uterine samples were collected at different stages of the estrous cycle and after insemination/early pregnancy. In the endometrium, the expression of ERalpha mRNA and PR mRNA was similar for cyclic and early pregnant groups. Both were highest at early diestrus/70 h after ovulation and ERalpha mRNA was lowest at late diestrus/d 19 while PR mRNA was lowest at diestrus and late diestrus/d 11 and d 19. The expression of endometrial ERbeta was constantly low during the estrous cycle but higher expression was found in inseminated/early pregnant sows at estrus and 70 h after ovulation. In the myometrium, high expression of ERalpha mRNA and PR mRNA was observed at proestrus and estrus in cyclic sows and at estrus in newly inseminated sows. Higher expression of myometrial ERbeta mRNA was found in inseminated/early pregnant sows compared with cyclic sows, although significant only at estrus. In conclusion, the expression of mRNAs for ERalpha, ERbeta and PR in the sow uterus differed between endometrium and myometrium as well as with stages of the estrous cycle and early pregnancy. In addition to plasma steroid levels, the differences between cyclic and inseminated/early pregnant sows suggest that other factors, e.g. insemination and/or the presence of embryos, influence the expression of these steroid receptor mRNAs in the sow uterus.     

Genetics of crossbred sow longevity

The aim of this study was to estimate genetic parameters for longevity from Swedish crossbred sows to investigate the possibilities of selecting for this trait. Data were collected from 16 commercial piglet-producing herds, on crossbred (Landrace × Yorkshire) sows farrowing in the period 1 January 2001 to 31 December 2004. The data set with records on 10 373 sows was split into two sets according to the breed of the sire, i.e. Landrace sires (LS) or Yorkshire sires (YS). Removal hazard during productive life (PL) was analysed with survival analysis, using a sire model. Stayability from first to second litter (STAY12), stayability from first to third litter (STAY13), length of productive life (LPL) and lifetime production (LTP) were analysed with linear models, using an animal model. Females after the worst sire had 1.7 times higher (progeny of LS) and 2.4 times higher (progeny of YS) risk of removal than females after the best sire. Heritability for PL was estimated at 0.06 (LS) and 0.12 (YS). The heritabilities for the linear longevity traits ranged from 0.03 to 0.08. Genetic correlations between the four linear longevity traits were all high and positive (0.6 to 1.0), as were the phenotypic correlations (0.5 to 0.8). The correlations (Spearman rank) between the sire's estimated breeding values for all the five longevity traits were all significant (P < 0.001) and moderate to strong in both data sets. Estimated breeding value (EBV) correlations between the five longevity traits and traits included in the present Swedish breeding evaluation (Quality Genetics (QG)) were significant in a few cases. Significant and favourable EBV correlations were found between age at first farrowing and both STAY12 and STAY13 (-0.20 and -0.31), as well as between litter weight at 3 weeks and LPL and LTP (0.13 to 0.20). Significant and unfavourable EBV correlations were found between age at 100 kg and STAY12 (0.32), as well as between the exterior conformation score from testing station and PL (-0.20). The level of the estimated heritabilities for longevity indicates that genetic improvement of sow longevity would be possible. However, overall, there was no strong indirect selection for sow longevity with the current Swedish breeding evaluation (QG).     

TRP-2 expression protects HEK cells from dopamine- and hydroquinone-induced toxicity

We previously reported that melanogenic enzyme TRP-2 (or DCT for DOPAchrome tautomerase) expression in WM35 melanoma cells resulted in increased intracellular GSH levels, reduction in DNA damage induced by free radicals, and decreased cell sensitivity to oxidative stress. These effects seemed to depend on a particular cellular context, because none of them were found to occur in HEK epithelial cells. We postulated that the TRP-2 beneficial effect observed in WM35 cells in the oxidative stress situation may relate to quinone metabolization and, more precisely, to the ability of TRP-2 to clear off related toxic metabolites, resulting in a global redox status modification. Here, a comparative protein expression profiling of catecholamine biosynthesis enzymes and detoxification enzymes was conducted in WM35 melanoma cells and in HEK epithelial cells, in comparison with normal human melanocytes. Results showed that WM35 cells, but not HEK cells, expressed enzymes involved in catecholamine biosynthesis, suggesting that their quinone-related toxic metabolites were present in WM35 cells but not in HEK cells. To address the issue of a possible TRP-2 beneficial effect toward quinone toxicity, cell survival experiments were then conducted in HEK cells using dopamine and hydroquinone at toxic concentrations. We showed that TRP-2 expression significantly reduced HEK cell sensitivity to both compounds. This beneficial property of TRP-2 was likely to depend on the integrity of its DOPAchrome tautomerase catalytic site, because both TRP-2(R194Q) and TRP-2(H189G), which have lost their DOPAchrome tautomerase activity, failed to modify the HEK cell response to dopamine and hydroquinone. These results suggest that TRP-2 acts on quinone metabolites other than DOPAchrome, e.g., in the catecholamine pathway, and limits their deleterious effects.     

Technologically indicative properties of straw fractions of flax, linseed (Linum usitatissimum L.) and fibre hemp (Cannabis sativa L.)

In this study of the behaviour of the fractions of unretted and frost-retted fibre straws in damp air, a production scale method to separate fibre and shive from fibre plants was introduced and tested on bast fibre plants (Linum usitatissimum L. and Cannabis sativa L.). The method consists of optional drying of stalks, unloading bales, milling the straws with a hammer mill, separating the fractions from air stream with a cyclone and finally separating fibres from shives with a screening drum. Fractions were characterized focusing on technologically indicative properties such as equilibrium moisture content, ash and microbiological quality. Unretted fractions of the bast fibre plant stem reached higher equilibrium moisture contents than the retted fractions, and hemp fibres absorbed more moisture from air than did the Linum fibres. In very humid air, all fractions began to lose weight due to moulding. The weight decrease during the first week was lower in frost-retted than in unretted fractions. The frost-retted fractions appeared to be more resistant to humidity in the short term. The total number of microbes and especially the numbers of yeasts and moulds can be used as a criterion of hygienic level. For green fractions, the mould level was similar in fibres and in shives, but frost-retted shives contained more moulds than the unretted shives. The mould content of a fraction had no direct correlation with the moulding tendency of the fraction. The ash contents of fibres were somewhat higher than those of shives, due to a probable soil contamination. Ash content did not have significant correlation with microbiological quality, although ash is a possible risk factor for hygienic quality. According to the results of this study it is highly important to study the quality of the production chain of bast fibre plants to ensure the quality of industrial products. From the producer's point of view, raw material with defined quality can be directed to the most suitable application. The behaviour of fractions in various ambient atmospheres, and other quality aspects such as hygienic level can be used as criteria for defining the most appropriate product applications.     

An implementation of the HACCP system in the production of food-packaging material

The Hazard Analysis Critical Control Point (HACCP) system according to the Codex Alimentarius model was applied to the processes of five paper and paperboard mills and four plants further converting paper or board intended for contact with foodstuffs. The generalised flow diagrams of the processes are presented. Each of the overall processes contained 40–150 process steps. Normally three to five sessions with HACCP teams and additional private negotiations were needed for each mill or plant. Hazards leading to critical control points (CCPs) were microbiological (handling/storage, circulation water, starch, process environment) and physical (process environment) in mills, and microbiological (storage, lacquers or glues, packaging and process environment), chemical (printing) and physical (storage of products, packaging and process environment) in plants. Specifications, critical limits (e.g., based on different kinds of reports and instructions), monitoring methods (microbiological and visual) and frequency, responsibilities and corrective actions of the processes are presented. Most of the improvements focused on improving the process environment. In five cases, hygiene training was included in the implementation of the HACCP system. Journal of Industrial Microbiology & Biotechnology (2002) 28, 213–218 DOI: 10.1038/sj/jim/7000233 Received 04 April 2001/ Accepted in revised form 06 December 2001     

In search of adult renal stem cells

The therapeutic potential of adult stem cells in the treatment of chronic degenerative diseases has becoming increasingly evident over the last few years. Significant attention is currently being paid to the development of novel treatments for acute and chronic kidney diseases too. To date, promising sources of stem cells for renal therapies include adult bone marrow stem cells and the kidney precursors present in the early embryo. Both cells have clearly demonstrated their ability to differentiate into the kidney's specialized structures. Adult renal stem cells have yet to be identified, but the papilla is where the stem cell niche is probably located. Now we need to isolate and characterize the fraction of papillary cells that constitute the putative renal stem cells. Our growing understanding of the cellular and molecular mechanisms behind kidney regeneration and repair processes - together with a knowledge of the embryonic origin of renal cells - should induce us, however, to bear in mind that in the kidney, as in other mesenchymal tissues, the need for a real stem cell compartment might be less important than the phenotypic flexibility of tubular cells. Thus, by displaying their plasticity during kidney maintenance and repair, terminally differentiated cells may well function as multipotent stem cells despite being at a later stage of maturation than adult stem cells. One of the major tasks of Regenerative Medicine will be to disclose the molecular mechanisms underlying renal tubular plasticity and to exploit its biological and therapeutic potential.     

Analysis of the evolutionary relationships of HIV-1 and SIVcpz sequences using bayesian inference: implications for the origin of HIV-1

The most plausible origin of HIV-1 group M is an SIV lineage currently represented by SIVcpz isolated from the chimpanzee subspecies Pan troglodytes troglodytes. The origin of HIV-1 group O is less clear. Putative recombination between any of the HIV-1 and SIVcpz sequences was tested using bootscanning and Bayesian-scanning plots, as well as a new method using a Bayesian multiple change-point (BMCP) model to infer parental sequences and crossing-over points. We found that in the case of highly divergent sequences, such as HIV-1/SIVcpz, Bayesian scanning and BMCP methods are more appropriate than bootscanning analysis to investigate spatial phylogenetic variation, including estimating the boundaries of the regions with discordant evolutionary relationships and the levels of support of the phylogenetic clusters under study. According to the Bayesian scanning plots and BMCP method, there was strong evidence for discordant phylogenetic clustering throughout the genome: (1) HIV-1 group O clustered with SIVcpzANT/TAN in middle pol, and partial vif/env; (2) SIVcpzGab1 clustered with SIVcpzANT/TAN in 3'pol/vif, and middle env; (3) HIV-1 group O grouped with SIVcpzCamUS and SIVcpzGab1 in p17/p24; (4) HIV-1 group M was more closely related to SIVcpzCamUS in 3'gag/pol and in middle pol, whereas in partial gp120 group M clustered with group O. Conditionally independent phylogenetic analysis inferred by maximum likelihood (ML) and Bayesian methods further confirmed these findings. The discordant phylogenetic relationships between the HIV-1/SIVcpz sequences may have been caused by ancient recombination events, but they are also due, at least in part, to altered rates of evolution between parental SIVcpz lineages.     

Phosphatidylinositol promotes cholesterol transport and excretion

Administration of phosphatidylinositol (PI) to New Zealand White rabbits increases HDL negative charge and stimulates reverse cholesterol transport. Intravenously administered PI (10 mg/kg) associated almost exclusively with the HDL fraction in rabbits. PI promoted an increase in the hepatic uptake of plasma free cholesterol (FC) and a 21-fold increase in the biliary secretion of plasma-derived cholesterol. PI also increased cholesterol excretion into the feces by 2.5-fold. PI directly affects cellular cholesterol metabolism. In cholesterol-loaded macrophages, PI stimulated cholesterol mass efflux to lipid-poor reconstituted HDL. PI was about half as effective as cAMP at stimulating efflux, and the effects of cAMP and PI were additive. In cultured HepG2 cells, PI-enriched HDL also enhanced FC uptake from HDL by 3-fold and decreased cellular cholesterol synthesis and esterification. PI enrichment had no effect on the selective uptake of cholesterol esters or on the internalization of HDL particles. PI-dependent metabolic events were efficiently blocked by inhibitors of protein kinase C and the inositol signaling cascade.The data suggest that HDL-PI acts via cell surface ATP binding cassette transporters and signaling pathways to regulate both cellular and intravascular cholesterol homeostasis.     

Apoptosis is mediated by cytosolic phospholipase A2 during simulated ischaemia/reperfusion-induced injury in neonatal cardiac myocytes

It has become increasingly clear that apoptosis plays a major role in ischaemia/reperfusion (I/R)-induced cell death, but the molecular basis of this process remains to be elucidated. Therefore, the aim of this study was to investigate the role of cPLA(2) in MAPK phosphorylation and apoptosis in simulated ischaemia/reperfusion (SI/R)-induced injury in neonatal cardiomyocytes. Inhibition of cPLA(2) with AACOCF(3) significantly improved cell viability during SI/R (60.17+/-1.77 to 80.17+/-1.97%, p<0.05). The increase in cell viability was associated with a significant inhibition of p38 phosphorylation (135.3+/-4.47% to 87.94+/-10.71%, p<0.001) as well as with a significant decrease in caspase-3- (320.32+/-17.32% to 146.7+/-28.69%, p<0.01) and PARP-(263.9+/-8.15% to 154.7+/-2.24%, p<0.001) cleavage during SI/R. This study provides evidence for a role for cPLA(2) during SI/R-induced injury. It appears that p38 MAPK is a central role player in the signalling pathway involved.