Expression of genes coding melatonin and serotonin receptors in rodent skin

Targeted search for expression of melatonin and serotonin receptors genes in the skin of C57BL/6J mice showed expression of MT1B (but not MT1A). Mouse skin and hamster melanomas also expressed 5HT2B and 5HT7. We identified two novel isoforms of MT1A and 5HT7.     

Influence of environmental factors and human activity on the presence of Salmonella serovars in a marine environment

The temporal and spatial distribution of Salmonella contamination in the coastal waters of Galicia (northwestern Spain) relative to contamination events with different environmental factors (temperature, wind, hours of sunlight, rainfall, and river flow) were investigated over a 4-year period. Salmonellae were isolated from 127 of 5,384 samples of molluscs and seawater (2.4%), and no significant differences (P < 0.05) between isolates obtained in different years were observed. The incidence of salmonellae was significantly higher in water column samples (2.9%) than in those taken from the marine benthos (0.7%). Of the 127 strains of Salmonella isolated, 20 different serovars were identified. Salmonella enterica serovar Senftenberg was the predominant serovar, being represented by 54 isolates (42.5%), followed by serovar Typhimurium (19 isolates [15%]) and serovar Agona (12 isolates [9.4%]). Serovar Senftenberg was detected at specific points on the coast and could not be related to any of the environmental parameters analyzed. All serovars except Salmonella serovar Senftenberg were found principally in the southern coastal areas close to the mouths of rivers, and their incidence was associated with high southwestern wind and rainfall. Using multiple logistic regression analysis models, the prevalence of salmonellae was best explained by environmental parameters on the day prior to sampling. Understanding this relationship may be useful for the control of molluscan shellfish harvests, with wind and rainfall serving as triggers for closure.     

Obestatin as a regulator of adipocyte metabolism and adipogenesis

The role of obestatin, a 23-amino-acid peptide encoded by the ghrelin gene, on the control of the metabolism of pre-adipocyte and adipocytes as well as on adipogenesis was determined. For in vitro assays, pre-adipocyte and adipocyte 3T3-L1 cells were used to assess the obestatin effect on cell metabolism and adipogenesis based on the regulation of the key enzymatic nodes, Akt and AMPK and their downstream targets. For in vivo assays, white adipose tissue (WAT) was obtained from male rats under continuous subcutaneous infusion of obestatin. Obestatin activated Akt and its downstream targets, GSK3α/β, mTOR and S6K1, in 3T3-L1 adipocyte cells. Simultaneously, obestatin inactivated AMPK in this cell model. In keeping with this, ACC phosphorylation was also decreased. This fact was confirmed in vivo in white adipose tissue (omental, subcutaneous and gonadal) obtained from male rats under continuous sc infusion of obestatin (24 and 72 hrs). The relevance of obestatin as regulator of adipocyte metabolism was supported by AS160 phosphorylation, GLUT4 translocation and augment of glucose uptake in 3T3-L1 adipocyte cells. In contrast, obestatin failed to modify translocation of fatty acid transporters, FATP1, FATP4 and FAT/CD36, to plasma membrane. Obestatin treatment in combination with IBMX and DEX showed to regulate the expression of C/EBPα, C/EBPβ, C/EBPδ and PPARγ promoting adipogenesis. Remarkable, preproghrelin expression, and thus obestatin expression, increased during adipogenesis being sustained throughout terminal differentiation. Neutralization of endogenous obestatin secreted by 3T3-L1 cells by anti-obestatin antibody decreased adipocyte differentiation. Furthermore, knockdown experiments by preproghrelin siRNA supported that obestatin contributes to adipogenesis. In summary, obestatin promotes adipogenesis in an autocrine/paracrine manner, being a regulator of adipocyte metabolism. These data point to a putative role in the pathogenesis of metabolic syndrome.     

Carotene Hydroxylase Activity Determines the Levels of Both α-Carotene and Total Carotenoids in Orange Carrots

The typically intense carotenoid accumulation in cultivated orange-rooted carrots (Daucus carota) is determined by a high protein abundance of the rate-limiting enzyme for carotenoid biosynthesis, phytoene synthase (PSY), as compared with white-rooted cultivars. However, in contrast to other carotenoid accumulating systems, orange carrots are characterized by unusually high levels of α-carotene in addition to β-carotene. We found similarly increased α-carotene levels in leaves of orange carrots compared with white-rooted cultivars. This has also been observed in the Arabidopsis thaliana lut5 mutant carrying a defective carotene hydroxylase CYP97A3 gene. In fact, overexpression of CYP97A3 in orange carrots restored leaf carotenoid patterns almost to those found in white-rooted cultivars and strongly reduced α-carotene levels in the roots. Unexpectedly, this was accompanied by a 30 to 50% reduction in total root carotenoids and correlated with reduced PSY protein levels while PSY expression was unchanged. This suggests a negative feedback emerging from carotenoid metabolites determining PSY protein levels and, thus, total carotenoid flux. Furthermore, we identified a deficient CYP97A3 allele containing a frame-shift insertion in orange carrots. Association mapping analysis using a large carrot population revealed a significant association of this polymorphism with both α-carotene content and the α-/β-carotene ratio and explained a large proportion of the observed variation in carrots.     

iPF2alpha-III-17,18,19,20-d4: total synthesis and metabolism

The first total synthesis of 17,18,19,20-d4-iPF2alpha-III 32, a deuterated analog of iPF2alpha-III, is described. We have used this analog in some beta-oxidation studies with rat liver homogenates and have shown that 32 was metabolized to 17,18,19,20-tetradeutero-2,3-dinor-iPF2alpha-III 36 and 17,18,19,20-tetradeutero-2,3-dinor-5,6-dihydro-iPF2alpha-III 37.     

In vivo short-term inhibition of nitrogenase by nitrate in Rhodopseudomonas capsulata E1F1

Abstract Respiratory activity of germinating cysts increased markedly during the first 2 h of differentiation whilst the sensitivity of respiration to potassium cyanide (KCN) increased. Similar changes could also be detected in membranes oxidizing NADH. The cytochrome content of cyst membranes exhibited both qualitative and quantitative changes during germination, the most notable being the appearance of cytochrome d at 2 h, the gradual decrease in levels of cytochrome o and the slow rise in the concentration of cytochrome a ₁. These modulations in respiratory activity during germination are compared with reports of other processes.     

Effect of vanadate on gill cilia: Switching mechanism in ciliary beat

Lateral (L) cilia of freshwater mussel (Margaritana margaritifera and Elliptio complanatus) gills can be arrested in one of two unique positions. When treated with 12.5 mM CaCl₂ and 10^?5 M A23187 they arrest in a “hands up” position, ie, pointing frontally. When treated with approximately 10 mM vanadate (V) they arrest in a “hands down” position, ie, pointing abfrontally. L-cilia treated with 12.5 mM CaCl₂ and 1 mM NaN₃ also arrest in a “hands down” position; substitution of 20 mM KC1 and 1 mM NaN₃ causes cilia to move rapidly and simultaneously to a “hands up” position. The observations suggest that there are two switching mechanisms for activation of active sliding in ciliary beat one at the end of the recovery stroke and the other at the end of the effective stroke; the first is inhibited by calcium and the second by vanadate or azide. This is consistent with a model of ciliary beating where microtubule doublet numbers 1, 2, 3, and 4 are active during the effective stroke while microtubule doublets numbers 6, 7, 8, and 9 are passive, and the converse occurs during the recovery stroke.     

Biometrics of exuviae of Cordulegaster boltonii algirica Morton, 1916 (Odonata: Cordulegastridae)

This study provides the first biometrics analysis of exuviae from Moroccan populations of the Ibero-Maghrebian endemic dragonfly Cordulegaster boltonii algirica Morton, 1916 collected in the Rif Mountains. Among the biometric variables that were measured, tibia length was highly correlated with the exuviae body length (BL), and can, therefore, be used to calculate the BL of partially broken exuviae. The head width exhibited the smallest coefficient of variation for both males and females and, therefore, is a valuable measurement that can be used for biometric comparison of different populations. The data presented herein will be used for future comparison with other North African and European populations of C. boltonii algirica.