Traces of human migrations in Helicobacter pylori populations

Helicobacter pylori, a chronic gastric pathogen of human beings, can be divided into seven populations and subpopulations with distinct geographical distributions. These modern populations derive their gene pools from ancestral populations that arose in Africa, Central Asia, and East Asia. Subsequent spread can be attributed to human migratory fluxes such as the prehistoric colonization of Polynesia and the Americas, the neolithic introduction of farming to Europe, the Bantu expansion within Africa, and the slave trade.     

Cartilage acidic protein-1B (LOTUS), an endogenous Nogo receptor antagonist for axon tract formation

Neural circuitry formation depends on the molecular control of axonal projection during development. By screening with fluorophore-assisted light inactivation in the developing mouse brain, we identified cartilage acidic protein-1B as a key molecule for lateral olfactory tract (LOT) formation and named it LOT usher substance (LOTUS). We further identified Nogo receptor-1 (NgR1) as a LOTUS-binding protein. NgR1 is a receptor of myelin-derived axon growth inhibitors, such as Nogo, which prevent neural regeneration in the adult. LOTUS suppressed Nogo-NgR1 binding and Nogo-induced growth cone collapse. A defasciculated LOT was present in lotus-deficient mice but not in mice lacking both lotus- and ngr1. These findings suggest that endogenous antagonism of NgR1 by LOTUS is crucial for normal LOT formation.     

Palladium-catalyzed aerobic dehydrogenation of substituted cyclohexanones to phenols

Aromatic molecules are key constituents of many pharmaceuticals, electronic materials, and commodity plastics. The utility of these molecules directly reflects the identity and pattern of substituents on the aromatic ring. Here, we report a palladium(II) catalyst system, incorporating an unconventional ortho-dimethylaminopyridine ligand, for the conversion of substituted cyclohexanones to the corresponding phenols. The reaction proceeds via successive dehydrogenation of two saturated carbon-carbon bonds of the six-membered ring and uses molecular oxygen as the hydrogen acceptor. This reactivity demonstrates a versatile and efficient strategy for the synthesis of substituted aromatic molecules with fundamentally different selectivity constraints from the numerous known synthetic methods that rely on substitution of a preexisting aromatic ring.     

Recovery of antioxidant activity from carnosol quinone: antioxidants obtained from a water-promoted conversion of carnosol quinone

Carnosol is one of the main antioxidants in sage and rosemary. Although carnosol quinone is the antioxidation product of carnosol and has a very weak antioxidant activity, its treatment in water-containing solvent restored its strong antioxidant activity. HPLC analysis of the water-stimulated recovery reaction of the antioxidant activity revealed that the strong activity was due to the reproduced carnosol. The analysis also showed that an almost equal amount of quinone derivatives of rosmanol (rosmanol quinone) was produced in the reaction along with the carnosol. The rosmanol was formed by the addition of 1 equiv of water and the following isomerization from carnosol quinone in the water-containing solvent. The formed rosmanol was also found to be oxidized by the remaining carnosol quinone to produce rosmanol quinone. At the same time, carnosol quinone was reduced to afford carnosol. This redox phenomenon is an important part of the mechanism for the recovery of the antioxidant activity from carnosol quinone under the water-containing conditions.     

Extracellular virulence factors of fish Vibrio: relationships between toxic material, hemolysin, and proteolytic enzyme

Biological activities of cell-free culture filtrate of 3 virulent strains of fish Vibrio were examined to determine the relationship to the pathogenesis of fish vibriosis. Among the 3 strains examined, V anguillarum strains NCMB6 and NCMB571 produced hemolysin and protease, whereas V ordalii strain N7802 did not. Culture filtrate of strain NCMB571 were lethal to rainbow trout and produced a cytotoxic effect on fish cell line. Results revealed that the extracellular products may be involved in the pathogenesis of fish vibriosis.     

Real-space observation of helical spin order

Helical spin order in magnetic materials has been investigated only in reciprocal space. We visualized the helical spin order and dynamics in a metal silicide in real space by means of Lorentz electron microscopy. The real space of the helical spin order proves to be much richer than that expected from the averaged structure; it exhibits a variety of magnetic defects similar to atomic dislocations in the crystal lattice. The application of magnetic fields allows us to directly observe the deformation processes of the helical spin order accompanied by nucleation, movement, and annihilation of the magnetic defects.     

Reliability in somatic cell count measurement of clinical mastitis milk using DeLaval cell counter

Somatic cell counts (SCC) measurements are typically performed using quantitative methods, such as the Breed method (Breed) and the Fossomatic method (FSCC). The DeLaval cell counter (DCC) developed recently is a quantitative somatic cell counter with a low initial cost and superior portability. However, since the DCC was specifically developed for measuring SCC of ≤ 4 × 10⁶ cells/mL milk from bulk tanks or individual cows, its reliability for estimating SCC that exceed this concentration has not yet been clarified. This study therefore examined whether it is possible to accurately measure SCC by diluting milk samples with initial SCC of 4 × 10⁶ cells/mL, as seen in clinical mastitis milk. We collected milk samples from 99 quarters of 99 Holstein cows with clinical mastitis. These milk samples were diluted 10‐fold with saline and thoroughly mixed before performing SCC measurement with the DCC. The correlation coefficients of SCC measured by the FSCC, Breed and DCC methods indicated strong correlations between each pair of methods. The findings showed that DCC can be used to identify bovine clinical mastitis milk and is useful as a quantitative SCC measurement device on farm sites.