Expression of a Vibrio parahaemolyticus toxin in Escherichia coli results in chromosomal DNA degradation

A toxin-antitoxin system, vp1842/vp1843, locates within a superintegron on the Vibrio parahaemolyticus genome chromosome I whose toxin gene vp1843 encodes a DNA nicking endonuclease. We found that the vp1843 expression in Escherichia coli cells strongly induced chromosomal DNA degradation. On the basis of these observations, we discuss a possible physiological role of vp1842/vp1843 in V. parahaemolyticus.     

Rapid detection of Brucella spp. by the loop-mediated isothermal amplification method

Aims:  To develop a rapid and sensitive method for detecting Brucella spp.
Methods and Results:  Two sets of six Brucella -specific primers for loop-mediated isothermal amplification (LAMP) were designed from the sequence of the Brucella abortus BCSP31 gene. The specificity and sensitivity were examined for six Brucella species (22 strains) and 18 non- Brucella species (28 strains). The LAMP assay was specific to Brucella spp. in 35 min at 63°C and sensitive (detected 10 fg of genomic DNA). The assay was also applied for the detection of Brucella DNA in contaminated milk and infected mouse organs.
Conclusions:  We developed a sensitive and specific LAMP assay for Brucella spp., with the test appearing to be useful for the detection of the pathogen from clinical and food samples.
Significance and Impact of the Study:  This is the first report of the development of LAMP for the detection of Brucella spp. As the LAMP assay can be performed at a constant temperature and its reactivity is directly observed with the naked eye without electrophoresis, our assay should be useful for the diagnosis of brucellosis as well as the detection of the bacteria in environmental or food samples.     

Properties and Role of Glyceraldehyde-3-Phosphate Dehydrogenase in the Control of Fermentation Pattern and Growth in a Ruminal Bacterium, <Emphasis Type="Italic">Streptococcus bovis</Emphasis>

To clarify the control of glycolysis and the fermentation pattern in Streptococcus bovis, the molecular and enzymatic properties of NAD⁺-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were examined. The GAPDH gene (gapA) was found to cluster with several others, including those that encode phosphoglycerate kinase and translation elongation factor G, however, gapA was transcribed in a monocistronic fashion. Since biochemical properties, such as optimal pH and affinity for glyceraldehyde-3-phosphate (GAP), were not very different between GAPDH- and NADP⁺-specific glyceraldehyde-3-phosphate dehydrogenase (GAPN), the flux from GAP may be greatly influenced by the relative amounts of these two enzymes. Using S. bovis JB1 as a parent, JB1gapA and JB1ldh, which overproduce GAPDH and lactate dehydrogenase (LDH), respectively, were constructed to examine the control of the glycolytic flux and lactate production. There were no significant differences in growth rates and formate-to-lactate ratios among JB1, JB1gapA, and JB1ldh grown on glucose. When grown on lactose, JB1ldh showed a much lower formate-to-lactate ratio than JB1gapA, which showed the highest NADH-to-NAD⁺ ratio. However, growth rates did not differ among JB1, JB1gapA, and JB1ldh. These results suggest that GAPDH is not involved in the control of the glycolytic flux and that lactate production is mainly controlled by LDH activity.     

Periodate-resistant carbohydrate epitopes recognized by IgG and IgE antibodies from some of the immunized mice and patients with allergy

The β(1,2)-xylose- and/or α(1,3)-fucose-containing cross-reactive carbohydrate determinants (CCDs) are present in various plant and insect N-glycans, and have been attracted as potential antigens in IgE-mediated allergies and immunologically undesired post-translational products on some recombinant therapeutic proteins. By using ELISA and immunoblotting, CCDs-specific IgG and IgE antibodies from some, but not all, of mice and humans were found to fully retain their binding activity after a typical periodate-treatment to CCDs, which did cause the CCDs’ antigenic activity to those from the other mice and rabbits to disappear almost completely. Furthermore, the mouse IgE recognizing the periodate-resistant CCDs induced the CCDs/IgE-dependent degranulation of rat basophilic RBL-2H3 cells. These findings indicate that in some cases CCDs include those dependent of the core trisaccharide more strongly than the terminal xylose and fucose, which might have been screened out in the CCDs analyses based on the loss of antibody-binding by the periodate-treatment.     

Species‐dependent microarchitectural traits of iridescent scales in the triad taxa of Ornithoptera birdwing butterflies

Ornithoptera birdwing butterflies have blue, green, or orange iridescent scales in different species or subspecies. To understand the species‐ or subspecies‐dependent scale color differences, we performed comparative morphometric analyses of iridescent scales from three closely related taxa: O. priamus priamus (green), O. priamus urvillianus (blue), and O. croesus (orange). The three types of Ornithoptera wings exhibited reversible color changes to longer wavelengths with different kinetics upon immersion in methanol, suggesting that their color differences are at least partly based on differences in the size of air cavities made by nanostructures. Cover scales of all three color types were visually semi‐transparent glass scales that exhibited color when placed on a dark background. The dorsoventral differences in coloration were observed in single scales, suggesting the optical importance of scale surfaces. Scanning electron microscopy of cover scales in cross section revealed that all color types exhibited finely sculpted tapered ridges and thick, irregular basal multilayers containing tandemly clustered granular objects and air cavities. Scale thickness, ridge height, and multilayer thickness were significantly different among the three color types, and granular object size was significantly different between orange scales and blue and green scales. We conclude that each of the three taxa of Ornithoptera butterflies possesses unique quantitative size values on tapered ridges and irregular multilayers with granular objects and air cavities to express unique structural color. These species‐ or subspecies‐dependent structural colors might have evolved via quantitative shifts in these microarchitectural traits rather than via changes in the basic developmental or architectural plan for color expression.     

Potential benefit of bosentan therapy in borderline or less severe pulmonary hypertension secondary to idiopathic pulmonary fibrosis—an interim analysis of results from a prospective,single-center,randomized, parallel-group study

Background

No drugs have been approved for the treatment of patients with pulmonary hypertension (PH) secondary to idiopathic pulmonary fibrosis (IPF), particularly those with idiopathic honeycomb lung. This study was conducted to investigate the long-term efficacy and safety of bosentan for PH based on changes in prognosis and respiratory failure.

Methods

IPF patients with borderline or less severe PH and completely organized honeycomb lung were randomized (1:1) to bosentan or no treatment for PH for 2 years and assessed at baseline and every 6 months for respiratory failure, activities of daily living (ADL), lung and heart functions by right cardiac catheterization, and other parameters. An interim analysis was performed, however, following detection of a significant survival benefit favoring bosentan therapy.

Results

Significant differences were noted for the bosentan-treated (n?=?12) vs. untreated (n?=?12) groups in hospital-free survival (603.44?±?50.074 days vs. 358.87?±?68.65 days; hazard ratio [HR], 0.19; P?=?0.017) and overall survival (671 days vs. 433.78?±?66.98 days; HR, 0.10; P?=?0.0082). Again, significant improvements were noted for the bosentan-treated group from baseline to month 6 or 12 in several indices in ADL, pulmonary circulation, and %DLCO. Without requiring O₂ inhalation, bosentan was associated with no increase but a trend toward a decrease in adverse events and an improvement in respiratory status.

Conclusions

Bosentan tended to improve prognosis and ADL without worsening respiratory failure in IPF patients with borderline or less severe PH and completely organized honeycomb lung alone.

Trial registration

This study was registered on December 18, 2010 with UMIN-CTR Clinical Trial as UMIN000004749 to investigate the long-term influence of bosentan on cardiac function, as well as its cardioprotective efficacy and safety, in patients with pulmonary hypertension secondary to concurrent COPD and IPF, respectively.

     

Dietary adaptations of temperate primates: comparisons of Japanese and Barbary macaques

Habitat, diet and leaf chemistry are compared between Japanese and Barbary macaques to reveal the similarities and differences in dietary adaptations of temperate primates living at the eastern and western extremes of the genus Macaca. Tree species diversity and proportion of fleshy-fruited species are much higher in Japan than in North Africa. Both species spend considerable annual feeding time on leaves. Japanese macaques prefer fruits and seeds over leaves, and Barbary macaques prefer seeds. These characteristics are adaptive in temperate regions where fruit availability varies considerably with season, since animals can survive during the lean period by relying on leaf and other vegetative foods. The two species are different with respect to the higher consumption of herbs by Barbary macaques, and the leaves consumed contain high condensed and hydrolysable tannin for Barbary but not for Japanese macaques. Barbary macaques supplement less diverse tree foods with herbs. Because of the low species diversity and high tannin content of the dominant tree species, Barbary macaques may have developed the capacity to cope with tannin. This supports the idea that digestion of leaves is indispensable to survive in temperate regions where fruit and seed foods are not available for a prolonged period during each year.     

Intraspecific differences in benefits from feeding in mixed-species flocks

The Madagascar Paradise Flycatcher Terpsiphone mutata and Common Newtonia Newtonia brunneicauda frequently form two-species flocks in the deciduous dry forest of western Madagascar. In T. mutata , some males have long tails, while other males and females have short tails. When foraging in mixed flocks, each type of bird captured prey more rapidly than otherwise, but the degree of increase in feeding rate was smaller in long-tailed males. When in mixed flocks, all T. mutata caught prey on leaves in the canopy where N. brunneicauda foraged. Long-tailed males changed feeding habits from sallying when not in mixed flocks, whereas short-tailed birds showed no change of feeding habit. The elongated tails of long-tailed males may have made their foraging less efficient owing to decreased agility in the canopy. N. brunneicauda is monomorphic and often formed groups of three to five individuals. In monospecific flocks, subordinates fed at low rates on branches owing to frequent hostile encounters. When foraging in mixed flocks, however, subordinates foraged among leaves, and their feeding rates increased because the frequency of intraspecific interference decreased greatly. Dominants did not show any difference in feeding pattern with social situation. Thus, heterospecific flocking was more advantageous for subordinates.