Is vegetative area,photosynthesis, or grape C uploading involved in the climate change-related grape sugar/anthocyanin decoupling in Tempranillo?

Foreseen climate change is expected to impact on grape composition, both sugar and pigment content. We tested the hypothesis that interactions between main factors associated with climate change (elevated CO₂, elevated temperature, and water deficit) decouple sugars and anthocyanins, and explored the possible involvement of vegetative area, photosynthesis, and grape C uploading on the decoupling. Tempranillo grapevine fruit-bearing cuttings were exposed to CO₂ (700 vs. 400 ppm), temperature (ambient vs. +?4 °C), and irrigation levels (partial vs. full) in temperature-gradient greenhouses. In a search for mechanistic insights into the underlying processes, experiments 1 and 2 were designed to maximize photosynthesis and enlarge leaf area range among treatments, whereas plant growth was manipulated in order to deliberately down-regulate photosynthesis and control vegetative area in experiments 3 and 4. Towards this aim, treatments were applied either from fruit set to maturity with free vegetation and fully irrigated or at 5–8% of pot capacity (experiments 1 and 2), or from veraison to maturity with controlled vegetation and fully irrigated or at 40% of pot capacity (experiments 3 and 4). Modification of air ¹³C isotopic composition under elevated CO₂ enabled the further characterization of whole C fixation period and C partitioning to grapes. Increases of the grape sugars-to-anthocyanins ratio were highly and positively correlated with photosynthesis and grape ¹³C labeling, but not with vegetative area. Evidence is presented for photosynthesis, from fruit set to veraison, and grape C uploading, from veraison to maturity, as key processes involved in the establishment and development, respectively, of the grape sugars to anthocyanins decoupling.     

Lactic acid bacteria isolated from dairy products inhibit genotoxic effect of 4-nitroquinoline-1-oxide in SOS-chromotest

Antigenotoxic activity against 4-nitroquinoline-1-oxide (4-NQO) of lactic acid bacteria isolated from commercial dairy products was studied using SOS-Chromotest. The supernatants from bacteria-genotoxin co-incubations in general exhibited a strong suppression on SOS-induction produced by 4-NQO on the tester organism Escherichia coli PQ37 (sfiA::lacZ). High genotoxicity inhibition (>75%) was found for 31/67 of the examined bacteria and the maximum values of some strains within the species were as follows: Lactobacillus casei, 99.1%; L. plantarum, 93.3%; L. rhamnosus, 93.4%; L. acidophilus, 90.9%; L. delbrueckii subsp. bulgaricus, 85.7% and Bifidobacterium bifidum, 89.6%; Strains with low antigenotoxicity (5-60%) were evidenced in both L. acidophilus and L. delbrueckii subsp. bulgaricus, whereas some inactive strains were found only in L. casei and L. delbrueckii subsp. bulgaricus. Cell exposure to 100 degrees C for 15 min prevented antigenotoxicity and no effect was evidenced for cell-free spent media. The active strains survived at 0.1 mM 4-NQO exposure and generally presented some relevant functional properties, such as tolerance to bile (0.5%) or acid environment (pH 2.0) and adherence to Caco-2 enterocytes. Antigenotoxicity was always associated with modification of the 4-NQO absorbance profile.     

Effect of cholesterol epoxides on the inhibition of intercellular communication and on mutation induction in Chinese hamster V79 cells

Cholesterol, cholesterol-5 alpha, 6 alpha-epoxide, cholesterol-5 beta, 6 beta-epoxide and cholestane-3 beta,5 alpha,6 beta-triol were tested for their ability to induce mutations at the Na+/K+-ATPase loci of the Chinese hamster V79 cells. None of these compounds induced ouabain-resistant mutations compared to the background mutation frequency in the control cells. These compounds were further tested for their ability to inhibit intercellular communication, using the Chinese hamster V79 cell metabolic cooperation assay. The diastereomeric epoxides and cholestane-triol, but not cholesterol, were found to be inhibitors of intercellular communication in a manner similar to other known tumor promoters.     

Iodination of zeta protein by lactoperoxidase. Chloroperoxidase and chloramine T.

Normal and Rous sarcoma virus transformed chicken embryo fibroblasts cultured on petri dishes were labeled with ¹²⁵I by two enzymic methods and one chemical method. The enzymic labeling systems employed chloroperoxidase and lactoperoxidase. Hydrogen peroxide was generated by glucose oxidase and glucose. The chemical method used chloramine T as the oxidant for iodide ion. After solubilization of cells, SDS disc gel electrophoresis and gamma counting, it was found that only one cell protein was predominantly labeled in all three reactions. This protein, a major cell surface protein, has been previously identified and termed Zeta protein. Zeta protein disappears from transformed cells and is susceptible to trypsin digestion.     

An electron microscopic histochemical and X-ray microprobe study of spherites in a mussel

Transmission electron microscopic, histochemical and X-ray analytical microprobe techniques were used to study the inorganic-organic relationship in the spherites (calcospherules) from the mantle, i.e. subadjacent to the outer mantle epithelium, of the fresh-water mussel Amblema. These structures were shown to contain calcium which could be chelated by the flotation of sections on solutions of either formic acid or ethylene glycol bis-(beta-amino ethyl ether)-N, N1-tetra-acetic acid (EGTA), Analysis of both non-chelated and sections revealed a significant sulfur peak. Chelated spherites were also intensely stained with acid phosphotungstic acid (PTA), Such data is indicative of the presence of an organic glycoprotein (proteoglycan) matrix which could serve to bind mineral ions, thus forming organic-inorganic aggregates for calcium transport and homeostasis. In this regard, the spherites are analogous to both calcium phosphate containing mitochondrial granules and the initial calcification sites in vertebrate mineralizing tissues.     

Repeated Acetylcholine Receptor Antibody-Concentrations and Association to Clinical Myasthenia Gravis Development

Introduction

We aimed to examine the longitudinal association between Myasthenia Gravis (MG) clinical severity and concentration of acetylcholine receptor (AChR)-antibodies to evaluate if AChR-antibody variations correlate to disease severity. A positive AChR-antibody test is specific for MG.

Material and Methods

All patients from western Norway who had two or more AChR- antibody tests in the period 1983–2013 were identified. The Myasthenia Gravis Foundation of America (MGFA) Clinical Classification was used to grade disease development. Multiple ordinal logistic regression analysis was used to estimate a possible predictive effect for AChR-antibody concentration on MGFA classification result.

Results

In 67 patients two or more AChR-antibody tests with a corresponding MGFA-score were performed, with a total of 309 tests. 56 patients were treated with immunosuppressive drugs and 11 by pyridostigmine only. There was a positive association between concentration of AChR-antibodies and longitudinal MGFA-score for the subgroup with immunosuppressive treatment, but not for those treated with pyridostigmine only. This association between AChR-antibody concentration and MGFA score declined with increasing time since onset (p = 0.005 for the interaction of group×time×concentration).

Conclusions

For MG patients with immunosuppressive treatment, repeated AChR-antibody measurements give information about clinical development, and can therefore be of support in therapeutic decisions.     

Defence-related Enzymes in Pepper Roots During Interactions with Arbuscular Mycorrhizal Fungi and/or Verticillium dahliae

Previous studies have described that arbuscular mycorrhizal fungi (AMF) can reduce the deleterious effect of Verticillium dahliae Kleb. on pepper growth and yield. In mycorrhizal plants, the bioprotection against soil-borne pathogens can result from the preactivation of defence responses that include some structural modifications and the accumulation of Pathogenesis-Related (PR) proteins. Our first objective was to study if V. dahliae induced defence mechanisms in roots before infected pepper developed visible symptoms of disease. The second aim was to determine if AMF induced defence-related enzymatic activities in pepper roots before or after pathogen’s attack. Results showed that the colonization of pepper roots by Glomus deserticola (Trappe, Bloss and Menge) induced the appearance of new isoforms of acidic chitinases, superoxide dismutase (SOD) and, at early stages, peroxidases. In contrast, V. dahliae neither stimulated the phenylpropanoid pathway nor elicited hydrolytic activities in infected pepper roots. Only in mycorrhizal plants, the inoculation with V. dahliae slightly increased both phenylalanine ammonia-lyase (PAL) and peroxidase activities two weeks later. Mycorrhizal-specific induction of new isoforms of acidic chitinases and SOD together with enhanced peroxidase and PAL activities 2 weeks after pathogen inoculation could be involved in the biocontrol of Verticillium-induced wilt in pepper by AMF.     

Is gender difference in postnatal thyroid growth associated with specific expression patterns of androgen and estrogen receptors?

Variations in sex steroids bioavailability were linked to the gender difference in the growth of thyroid glands of neonatal rats. In the present study we tested androgen receptor (AR) and estrogen receptor (ER) concentrations by ligand binding assay, and expression of their genes by RT-PCR and Western blot in the thyroid glands of neonatal rats. AR concentration remained elevated from postnatal day (PND) 10 onwards in males, whereas it decreased by PND 20 in females. AR mRNA and protein expressions were higher in males than females, which increased by PND 10, decreased after PND 15 and reached the nadir by PND 20. ER concentration increased by PND 10 and decreased thereafter in both sex. ERα mRNA expression diminished by PND 15 in both sex; while ERβ mRNA decreased by PND 15 to reach the nadir by PND 20 in males, it was augmented by PND 10 in females to reach the peak by PND 15 and diminished by PND 20. ERα protein expression increased by PND 10 and remained elevated till PND 20 in both sex. ERβ protein expression in males increased by PND 10 and decreased by PND 20, while it remained static up to PND 15 and decreased in females. Testosterone stimulated [³H]-thymidine uptake and the expression of IGF-1 and NIS genes in thyrocytes of both sex in vitro, while estradiol stimulated them in females but not in males. We conclude that androgens influence the growth and differentiation of thyrocytes through augmented expression of AR, IGF-1 and NIS in either sex, whereas estrogen imparts the gender difference, which may be at a level beyond the expression of ERs.     

Application of antimicrobial polypeptide host defenses to aquaculture: Exploitation of downregulation and upregulation responses

Antimicrobial polypeptides (AMPPs), consisting of peptides and small proteins with antimicrobial activity, are an integral component of innate immunity. Their often potent properties and widespread prevalence in fish suggests that designing means of manipulating their levels has considerable potential for maintaining or improving fish health. There is evidence that a number of chronic stresses lead to significant downregulation of AMPPs and thus their monitoring could be a highly sensitive measure of health status and risk of an infectious disease outbreak. Conversely, upregulation of AMPP expression could be used to enhance disease resistance in stressful environments, as well as improve the efficacy of traditional antimicrobial drugs. However, further work is required in linking levels of a number of AMPPs to physiological function since, while a number of studies have documented the down- or upregulation of AMPPs via gene expression, relatively few studies have quantitatively examined changes in protein expression. In addition, not all AMPPs appear to be expressed at microbicidal levels in vivo, suggesting that at least some may have functions other than being directly protective. Nonetheless, in fish, there is evidence that some constitutively expressed AMPPs, such as piscidins and histone-like proteins, are expressed at microbicidal levels and that they decline with stress. Furthermore, certain AMPPs derived from hemoglobin-β are upregulated to microbicidal levels after experimental challenge. The likely widespread distribution of these three AMPP groups in fish provides the opportunity to design strategies to greatly improve the health of cultured fish populations.