Changes in calmodulin level after fertilization and during first cleavage in the egg of the urodelan amphibian Pleurodeles waltlii

We report three significant calmodulin rises related to Pleurodeles waltlii egg fertilization and following developmental events. These elevations are correlated to the major obvious Ca2+-dependent events: Na+-H+ exchange, activation of NAD kinase, triggering of cortical reaction, resumption of meiotic division II, initiation of DNA synthesis and regulation of cell division. Therefore, it is suggested that alterations in calmodulin level in fertilized egg may be part of the Ca2+-dependent regulatory mechanisms which turn on metabolisms, initiate development and govern cell cleavages.     

Ventilation in the shore crab Carcinus maenas (L.) as a function of ambient oxygen and carbon dioxide: Field and laboratory studies

Ventilatory responses of crabs Carcinus maenas (L.) to changes in ambient oxygen and carbon dioxide were studied in field and laboratory experiments, over a range of Pw_O2 and Pw_co2 conditions encompassing natural variations observed in intertidal rock-pools. Ventilatory activity was assessed by recording gill chamber hydrostatic pressure and estimating the specific ventilation, Vw/M_O2, the reciprocal of the difference of oxygen concentrations in inspired and expired waters.

Variations in ambient oxygenation always induced large changes of ventilatory activity, hyperventilation in hypoxia, hypoventilation in hyperoxia. Conversely, Pw_CO2 changes either at constant P_O2 or in combination with different P_O2 values (hypoxic hypercapnia or hyperoxic hypocapnia) led only to small or even non-significant ventilatory responses. In the field, strong hyperventilation developed during tidal exposure at night, when the pool water became hypoxic and hypercapnic, whereas during the day the animals hypoventilated in progressively more hyperoxic and hypocapnic conditions.

Thus, in a typical intertidal animal such as C. maenas, the only ventilatory stimulus of ecological significance appears to be the ambient water oxygenation.     

Qualitative and quantitative determination of major saponins in Paris and Trillium by HPLC-ELSD and HPLC–MS/MS

High-performance liquid chromatographic (HPLC) with evaporative light scattering detection (ELSD) and HPLC with electrospray ionization multistage tandem mass spectrometry (HPLC–ESI-MSⁿ) were used to identify and quantify steroid saponins in Paris and Trillium plants. The content of the known saponins such as Paris I, II, III, V, VI, VII, H, gracillin and protodioscin in Paris and Trillium plants was determined simultaneously using the developed HPLC-ELSD method. Furthermore, other 12 steroid saponins were identified by HPLC–ESI(+/−)-MSⁿ detection. In the end, a developed analytical procedure was proved to be a reliable and rapid method for the quality control of Paris and Trillium plants. In addition, the alternative resources for Paris yunnanensis used as a traditional Chinese medicine were discovered according to the hierarchical clustering analysis of the saponin fraction of these plants.     

Detecting latitudinal and altitudinal expansion of invasive bamboo Phyllostachys edulis and Phyllostachys bambusoides (Poaceae) in Japan to project potential habitats under 1.5°C–4.0°C global warming

Rapid expansion of exotic bamboos has lowered species diversity in Japan's ecosystems by hampering native plant growth. The invasive potential of bamboo, facilitated by global warming, may also affect other countries with developing bamboo industries. We examined past (1975–1980) and recent (2012) distributions of major exotic bamboos (Phyllostachys edulis and P. bambusoides) in areas adjacent to 145 weather stations in central and northern Japan. Bamboo stands have been established at 17 sites along the latitudinal and altitudinal distributional limit during the last three decades. Ecological niche modeling indicated that temperature had a strong influence on bamboo distribution. Using mean annual temperature and sun radiation data, we reproduced bamboo distribution (accuracy = 0.93 and AUC (area under the receiver operating characteristic curve) = 0.92). These results infer that exotic bamboo distribution has shifted northward and upslope, in association with recent climate warming. Then, we simulated future climate data and projected the climate change impact on the potential habitat distribution of invasive bamboos under different temperature increases (i.e., 1.5°C, 2.0°C, 3.0°C, and 4.0°C) relative to the preindustrial period. Potential habitats in central and northern Japan were estimated to increase from 35% under the current climate (1980–2000) to 46%–48%, 51%–54%, 61%–67%, and 77%–83% under 1.5°C, 2.0°C, 3.0°C, and 4.0°C warming levels, respectively. These infer that the risk areas can increase by 1.3 times even under a 1.5°C scenario and expand by 2.3 times under a 4.0°C scenario. For sustainable ecosystem management, both mitigation and adaptation are necessary: bamboo planting must be carefully monitored in predicted potential habitats, which covers most of Japan.     

Cytogeographic Study of the Genus Paris

The Genus Paris L., distributed in Europe and Asia, is one of the genera of Trilliaceae. There are currently 19 recognized species. The karyological study indicates that basic number of the Paris species is X=5, and here are two kinds of the basic karyotypes: tropical type (K2n=2x=10=6m+4t), and temperate type (K2n=2x=10=6m+4st, or 6m+ 2st+2t). The species (13) with the tropical karyotype are distributed in the tropical and subtropical regions in Asia; the others with the temperate karyotype (6 species) occur in the temperate area of Eurasia. In the genus Paris, there are two peripheral species, which both have temperate karyotypes: tetraploid P. quadrifolia, in the western part of the overall range of the genus (Europe), and octaploid P. japonica, limited in the eastern part (Japan). All the species having tropical karyotypes are diploid. Among them, the more primitive ones such as P. dunniana, P. vietnamensis are concentrated in South China and the north of the Indo-China Peninsula. Examination of the geographical distribution of the species in the light of the karyological data has led the authors to propose: Paris originated in the tropical area between 18°N and 23°27’N in Asia. 14 species, which together make up 74% of the total (with 10 different karyotypes), occur in the area from the Qionglei Mountains to the Yunnan-Guizhou Plateau. With the greatest density of species in the area and their remarkable differences in chromosome ploidy and karyotypes, this region is without doubt the centre of modern distribution and differentiation of Paris.     

Lettuce production and antioxidant capacity are differentially modified by salt stress and light intensity under ambient and elevated CO2

As a consequence of the increasing importance of vegetables in the human diet, there is an interest in enhancing both the productivity and quality of vegetables. A number of factors, including plant genotype and environmental growing conditions, can impact the production and quality of vegetables. The objective of this study was to determine whether elevated CO₂, salinity, or high light treatments assayed individually, or salinity or high light in combination with elevated CO₂, increased biomass production and antioxidant capacity in two lettuce cultivars. Elevated CO₂ and its combination with salinity or high light increased biomass production in both cultivars, while high light treatment alone increased production in green-leaf lettuce but not in red-leaf lettuce. On the other hand, elevated CO₂ and its combination with salinity or high light increased the antioxidant capacity of both cultivars, while high light treatment alone increased the antioxidant capacity of red-leaf lettuce, but not of green-leaf lettuce.     

New thylacocephalans from the Early Triassic Paris Biota (Bear Lake County,Idaho, USA)

Two new genera and species of thylacocephalans (Arthropoda, Thylacocephala), Parisicaris triassica Charbonnier and Ligulacaris parisiana Charbonnier, are described from the early Spathian Paris Biota. These new occurrences are the first reports of thylacocephalans from Triassic rocks in North America. They considerably enlarge the spatiotemporal distribution of these enigmatic arthropods and highlight their relatively high generic richness during the Early Triassic. It also confirms that the Triassic was the taxonomically richest period for Thylacocephala.