Digestive and metabolic utilization of lauric,myristic and stearic acid in cows,and associated effects on milk fat quality

A study was carried out to examine the effect of dietary supplementation of oregano essential oil on performance of broiler chickens experimentally infected with Eimeria tenella at 14 days of age. A total of 120 day-old Cobb-500 chicks separated into 4 equal groups with three replicates each, were used in this study. Two groups, one infected with 5·10⁴ sporulated oocysts of E. tenella and the other not, were given a basal diet and served as controls. The other two groups also infected with E. tenella were administered diets supplemented with oregano essential oil at a level of 300 mg/kg, or with the anticoccidial lasalocid at 75 mg/kg. Following this infection, survival rate, bloody diarrhoea and oocysts excretion as well as lesion score were determined. Throughout the experimental period of 42 days, body weight gain and feed intake were recorded weekly, and feed conversion ratios were calculated. Two weeks after the infection with E. tenella supplementation with dietary oregano oil resulted in body weight gains and feed conversion ratios not differing from the non-infected group, but higher than those of the infected control group and lower than those of the lasalocid group. These parameters correspond with the extent of bloody diarrhoea, survival rate, lesion score and oocyst numbers and indicated that oregano essential oil exerted an anticoccidial effect against E. tenella, which was, however, lower than that exhibited by lasalocid.     

Optimization of 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidines to generate a highly selective PI3Kδ inhibitor

Chemical optimization of the 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (THPP) scaffold was conducted with a focus on cellular potency while maintaining high selectivity against PI3K isoforms. Compound 11f was identified as a potent, highly selective and orally available PI3Kδ inhibitor. In addition, 11f exhibited efficacy in an in vivo antibody production model. The desirable drug-like properties and in vivo efficacy of 11f suggest its potential as a drug candidate for the treatment of autoimmune diseases and leukocyte malignancies.     

4-Aryl-5-carbamoyl-3-isoxazolols as competitive antagonists of insect GABA receptors: Synthesis,biological activity,and molecular docking studies

Competitive antagonists (CAs) of ionotropic GABA receptors (GABARs) reportedly exhibit insecticidal activity and have potential for development as novel insecticides for overcoming emerging resistance to traditional GABAR-targeting insecticides. Our previous studies demonstrated that 4,5-disubstituted 3-isoxazolols or 3-isothiazolols are an important class of insect GABAR CAs. In the present study, we synthesized a series of 4-aryl-5-carbamoyl-3-isoxazolols and examined their antagonism of insect GABARs expressed in Xenopus oocytes. Several of these 3-isoxazolols exhibited potent antagonistic activities against housefly and common cutworm GABARs, with IC₅₀ values in the low-micromolar range in both receptors. 4-(3-Amino-4-methylphenyl)-5-carbamoyl-3-isoxazolol (3u) displayed the highest antagonism, with IC₅₀ values of 2.0 and 0.9?μM in housefly and common cutworm GABARs, respectively. Most of the synthesized 3-isoxazolols showed moderate larvicidal activities against common cutworms, with more than 50% mortality at 100?μg/g. These results indicate that 4-monocyclic aryl-5-carbamoyl-3-isoxazolol is a promising scaffold for insect GABAR CA discovery and provide important information for the design and development of GABAR-targeting insecticides with a novel mode of action.     

Ploidy mosaicism in well-developed nuclear transplants produced by transfer of adult somatic cell nuclei to nonenucleated eggs of medaka (Oryzias latipes)

Chromosomal abnormalities such as ploidy mosaicism have constituted a major obstacle to the successful nuclear transfer of adult somatic cell nuclei in lower vertebrates to date. Euploid mosaicism has been reported previously in well-developed amphibian transplants. Here, we investigated ploidy mosaicisms in well-developed transplants of adult somatic cell nuclei in medaka fish (Oryzias latipes). Donor nuclei from primary cultured cells from the adult caudal fin of a transgenic strain carrying the green fluorescent protein gene (GFP) were transferred to recipient nonenucleated eggs of a wild-type strain to produce 662 transplants. While some of the transplants developed beyond the body formation stage and several hatched, all exhibited varying degrees of abnormal morphology, limited growth and subsequent death. Twenty-one transplants, 19 embryos and two larvae, were selected for chromosomal analysis; all were well-developed 6-day-old or later embryonic stages exhibiting slight morphological abnormalities and the same pattern of GFP expression as that of the donor strain. In addition, all exhibited various levels of euploid mosaicism with haploid-diploid, haploid-triploid or haploid-diploid-triploid chromosome sets. No visible chromosomal abnormalities were observed. Thus, euploid mosaicism similar to that observed in amphibians was confirmed in well-developed nuclear transplants of fish.     

Neurturin-GFRalpha2 signaling controls liver bud migration along the ductus venosus in the chick embryo

During chick liver development, the liver bud arises from the foregut, invaginates into the septum transversum, and elongates along and envelops the ductus venosus. However, the mechanism of liver bud migration is only poorly understood. Here, we demonstrate that a GDNF family ligand involved in neuronal outgrowth and migration, neurturin (NRTN), and its receptor, GFRalpha2, are essential for liver bud migration. In the chick embryo, we found that GFRalpha2 was expressed in the liver bud and that NRTN was expressed in the endothelial cells of the ductus venosus. Inhibition of GFRalpha2 signaling suppressed liver bud elongation along the ductus venous without affecting cell proliferation and apoptosis. Moreover, ectopic expression of NRTN perturbed the directional migration along the ductus venosus, leading to splitting or ectopic branching of the liver. We showed that liver buds selectively migrated toward an NRTN-soaked bead in vitro. These data represent a new model for liver bud migration: NRTN secreted from endothelial cells functions as a chemoattractant to direct the migration of the GFRalpha2-expressing liver bud in early liver development.     

Structural properties of a scaled gecko foot-hair

Experimental measurements on a cm-scale replica structure of a gecko foot-hair where magnets are used in place of (the usual) van der Waals force are reported. We conduct naked-eye experiments and investigate the mechanical properties of such hair structure and shapes that constitute it. Links between shapes and mechanical properties (functions) useful in geckos for clinging onto walls and adhering to rough surfaces are explained in terms of energy efficiency.     

Comparative analysis of a 229-kb medaka genomic region, containing the zic1 and zic4 genes, with Fugu, human, and mouse

Medaka is one of the prominent model animals, which also include other fishes such as Fugu and zebrafish. Its genome is relatively compact but has not been well characterized. Here we have sequenced a 229-kb region of medaka, containing the Double anal fin (Da) locus, and compared its structure to those in Fugu, human, and mouse. This region, representing a gene-poor region, contains no major rearrangements and can be readily compared among different species. Comparison of G+C contents and repeats suggested that medaka and Fugu are highly related as expected and that medaka is more similar to mammals than Fugu is. Sequence comparisons of developmental genes zic1 and zic4, identified within this region, revealed that zic1, but not zic4, is highly conserved among vertebrates. The 5' coding region of zic4 is, however, extremely homologous among fishes with little synonymous substitutions, implying its distinct function in fish.     

Molecular cloning, functional expression, and mutagenesis of cDNA encoding class I chitinase from rye (Secale cereale) seeds

A cDNA encoding rye seed chitinase-a (RSC-a) was cloned by rapid amplification of cDNA ends and PCR procedures. It consists of 1,191 nucleotides and encodes an open reading frame of 321 amino acid residues. Recombinant RSC-a (rRSC-a) was produced in the oxidative cytoplasm of Escherichia coli Origami(DE3) in a soluble form by inducing bacteria at a low temperature (20 degrees C). Purified rRSC-a showed properties similar to the original enzyme from rye seeds in terms of chitinase activity toward a soluble substrate, glycolchitin, and an insoluble substrate, chitin beads, in chitin-binding ability to chitin, and in antifungal activity against Trichoderma sp. in vitro. rRSC-a mutants were subsequently produced and purified by the same procedures as those for rRSC-a. Mutation of Trp23 to Ala decreased the chitinase activity toward both substrates and impaired the chitin-binding ability. Furthermore, the antifungal activity of this mutant was weakened with increasing of the NaCl concentration in the culture medium. Complete abolishment of both activities was observed upon the mutation of Glu126 to Gln. The roles of these residues in both activities are discussed.     

Role of taurine supplementation to prevent exercise-induced oxidative stress in healthy young men

Summary. To evaluate the protective effects of taurine supplementation on exercise-induced oxidative stress and exercise performance, eleven men aged 18–20 years were selected to participate in two identical bicycle ergometer exercises until exhaustion. Single cell gel assay (SCG assay) was used to study DNA damage in white blood cells (WBC). Pre-supplementation of taurine, a significant negative correlation was found between plasma taurine concentration before exercise and plasma thiobaribituric-acid reactive substance (TBARS) 6hr after exercise (r=–0.642, p<0.05). WBC showed a significant increase in DNA strand breakage 6hr and 24hr after exercise. Seven-day taurine supplementation reduced serum TBARS before exercise (p<0.05) and resulted in a significantly reduced DNA migration 24hr after exercise (p<0.01). Significant increases were also found in VO₂max, exercise time to exhaustion and maximal workload in test with taurine supplementation (p<0.05). After supplementation, the change in taurine concentration showed positive correlations with the changes in exercise time to exhaustion and maximal workload. The results suggest that taurine may attenuate exercise-induced DNA damage and enhance the capacity of exercise due to its cellular protective properties.