Fishing gears involved in entanglements of minke whales (Balaenoptera acutorostrata) in the East Sea of Korea

Entanglement of marine mammals in fishing gear is a global issue. It is considered a significant threat to minke whales (Balaenoptera acutorostrata) in the East Sea of Korea. A total of 214 entanglements of minke whales in this area between 2004 and 2007 were used to investigate types and parts of fishing gears involved in entanglements. The majority of entanglements were mainly caused by three types of fishing gears: set nets, pots, and gill nets (n= 207, 96.7%). Other entanglements were associated with bottom trawls, purse seines, and trawls. A total of 65 entanglements were attributed to the main and branch lines of fishing gears. The most common body part of minke whales which attached to fishing gears was the mouth (n= 63, 30.4%). Most entanglements took place within 10 nmi from land (n= 179, 86.5%), and between 10 and 220 m of water depth. The mean length of entangled minke whales in set nets was significantly smaller than that of whales in pots and gill nets samples (P < 0.001). Also, the mean body length of minke whales that entangled in the coastal area and shallow waters was significantly shorter than that of whales in the offshore area and deep waters (P < 0.001). This information can be used as fundamental data to conserve and manage this population of minke whales in the East Sea of Korea, and also to modify fishing gear to reduce entanglements. Future studies should focus on investigating the impact of these entanglements on the population and the effectiveness of mitigation measures to reduce entanglements of minke whales in this area.     

Toxicity of unsaturated fatty acids to the biohydrogenating ruminal bacterium, <Emphasis Type="Italic">Butyrivibrio fibrisolvens</Emphasis>

Background  

Health-promoting polyunsaturated fatty acids (PUFA) are abundant in forages grazed by ruminants and in vegetable and fish oils used as dietary supplements, but only a small proportion of PUFA finds its way into meat and milk, because of biohydrogenation in the rumen. Butyrivibrio fibrisolvens plays a major role in this activity. The aim of this study was to investigate the mechanisms by which PUFA affect the growth of B. fibrisolvens, how PUFA are metabolized and the metabolic response to growth in the presence of PUFA.     

Anti-hypercalcemic effect of orally administered recombinant <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis> expressing salmon calcitonin on hypercalcemic rats

Oral delivery of salmon calcitonin (sCT) to rats via a recombinant Saccharomyces cerevisiae was assessed. A synthetic sCT gene was cloned and expressed in S. cerevisiae yAGA2-sCT. Recombinant salmon calcitonin (rsCT) expression was detected by flow cytometry. The resorption activity of osteoclasts was inhibited by 3 × 10⁻⁶ M rsCT. Oral administration of 5 g lyophilized yAGA2-sCT/kg to hypercalcemic rats decreased serum calcium from 2.8 ± 0.02–2.7 ± 0.02 mM.     

Requirement of a mip-like gene for virulence in the phytopathogenic bacterium Xanthomonas campestris pv. campestris

Macrophage infectivity potentiators (Mips) are FKBP domain-containing proteins reported as virulence factors in several human pathogens, such as members of genera Legionella, Salmonella and Chlamydia. The putative peptidylprolyl cis-trans isomerase (PPIase) encoded by XC2699 of the plant bacterial pathogen Xanthomonas campestris pv. campestris 8004 exhibits a 49% similarity at the amino-acid level to the Mip protein of Legionella pneumophila. This mip-like gene, XC2699, was overexpressed in Escherichia coli and the purified (His)6-tagged Mip-like protein encoded by XC2699 exhibited a PPIase activity specifically inhibited by FK-506. A mutation in the mip-like gene XC2699 led to significant reductions in virulence and replication capacity in the host plant Chinese radish (Raphanus sativus L. var. radiculus Pers.). Furthermore, the production of exopolysaccharide and the activity of extracellular proteases, virulence factors of X. campestris pv. campestris, were significantly decreased in the mip-like mutant. These results reveal that the mip-like gene is involved in the pathogenesis of X. campestris pv. campestris through an effect on the production of these virulence factors.     

A chromium-tolerant plant growing in Cr-contaminated land

In this paper, a kind of Typhaceae plant species, Typha angustifolia L, with a high tolerance to Cr is described. Experiments were carried out to examine its ability to tolerant Cr and its physiological response. The results showed that there was no difference in growth, plant height, and biomass response to external Cr (VI) between the plants exposed to 100 microM Cr (VI) and control (0 microM), while increasing Cr levels to 200-800 microM induced a significant decrease in plant height and biomass, but no significant injury was detected, even for the plants exposed to 800 microM Cr. Chromium induced significant increases in superoxide dismutase (SOD) and peroxidase (POD) activities. Meanwhile, a significantly positive correlation was found between Cr and Mn or Cu in leaves and roots, respectively. The Cr tolerance of the plant appeared to be associated with the enhancement of SOD and POD activities and the improvement in uptake and translocation of the essential microelements.     

Notch signaling is essential for ventricular chamber development

Ventricular chamber morphogenesis, first manifested by trabeculae formation, is crucial for cardiac function and embryonic viability and depends on cellular interactions between the endocardium and myocardium. We show that ventricular Notch1 activity is highest at presumptive trabecular endocardium. RBPJk and Notch1 mutants show impaired trabeculation and marker expression, attenuated EphrinB2, NRG1, and BMP10 expression and signaling, and decreased myocardial proliferation. Functional and molecular analyses show that Notch inhibition prevents EphrinB2 expression, and that EphrinB2 is a direct Notch target acting upstream of NRG1 in the ventricles. However, BMP10 levels are found to be independent of both EphrinB2 and NRG1 during trabeculation. Accordingly, exogenous BMP10 rescues the myocardial proliferative defect of in vitro-cultured RBPJk mutants, while exogenous NRG1 rescues differentiation in parallel. We suggest that during trabeculation Notch independently regulates cardiomyocyte proliferation and differentiation, two exquisitely balanced processes whose perturbation may result in congenital heart disease.     

Comparative transcriptome analysis reveals the regulation network for fiber strength in cotton

Biotechnology Letters - Determine the effect of secondary cell wall (SCW) thickness and microcrystalline cellulose content (MCC) on mature fiber strength (FS) and reveal through comparative...     

Changes in Patterns of Species Co‐occurrence across Two Tropical Cloud Forests Differing in Soil Nutrients and Air Temperature

Patterns of co‐occurrence of species are increasingly used to examine the contribution of biotic interactions to community assembly. We assessed patterns of co‐occurrence at four scales, in two types of tropical cloud forests in Hainan Island, China (tropical montane evergreen forests, TMEF and tropical dwarf forests, TDF) that varied significantly in soil nutrients and temperature. We tested if the patterns of co‐occurrence changed when we sorted species into classes by abundance and diameter at breast height (dbh). Co‐occurrence differed by forest type and with plot size, with significant species aggregation observed across larger plots in TDF and patterns of species segregation observed in smaller plots in TMEF. Analyses of differential abundance and dbh classes also showed that smaller plots in TMEF tend to have negative co‐occurrence patterns, but larger plots in TDF tend to show patterns of aggregation, suggesting competitive and facilitative interactions. This underscores the scale‐dependence of the processes contributing to community assembly. Furthermore, it is consistent with predictions of the stress gradient hypothesis that facilitation will be most important in biological systems subject to abiotic stress, while competition will be more important in less abiotically stressful habitats. Our results clearly demonstrate that these two types of tropical cloud forest exhibit different co‐occurrence patterns, and that these patterns are scale‐dependent, though independent of plant abundance and size class.