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Pulmonary hypertension (PH) is a life-threatening disease characterized by vascular remodeling. Exploring new therapy target is urgent. The purpose of the present study is to investigate whether and how spliced x-box binding protein 1 (xbp1s), a key component of endoplasmic reticulum stress (ERS), contributes to the pathogenesis of PH. Forty male SD rats were randomly assigned to four groups: Control, Monocrotaline (MCT), MCT+AAV-CTL (control), and MCT+AAV-xbp1s. The xbp1s protein levels were found to be elevated in lung tissues of the MCT group. Intratracheal injection of adeno-associated virus serotype 1 carrying xbp1s shRNA (AAV-xbp1s) to knock down the expression of xbp1s effectively ameliorated the MCT-induced elevation of right ventricular systolic pressure (RVSP), total pulmonary resistance (TPR), right ventricular hypertrophy and medial wall thickness of muscularized distal pulmonary arterioles. The abnormally increased positive staining rates of proliferating cell nuclear antigen (PCNA) and Ki67 and decreased positive staining rates of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) in pulmonary arterioles were also reversed in the MCT+AAV-xbp1s group. For mechanistic exploration, bioinformatics prediction of the protein network was performed on the STRING database, and further verification was performed by qRT-PCR, Western blots and co-immunoprecipitation (Co-IP). DNA damage-inducible transcript 3 (Ddit3) was identified as a downstream protein that interacted with xbp1s. Overexpression of Ddit3 restored the decreased proliferation, migration and cell viability caused by silencing of xbp1s. The protein level of Ddit3 was also highly consistent with xbp1s in the animal model. Taken together, our study demonstrated that xbp1s-Ddit3 may be a potential target to interfere with vascular remodeling in PH.

The cytological characteristics of major green-tide-forming green algae Ulva prolifera collected from Yellow Sea were studied through cutting segments, long time low temperature or dark treatments. After being dried in the shade and preserved at -20°C for 30 days, the U. prolifera was cultured at 4°C in sterilized seawater under 40 μmol photons m-2·s-1 light intensity for 120 days, results indicated that the plastid of U. prolifera continuously shrank with the extension of treatment, and most cells turned white and died, only a small amount of cells still contained a few of visible inclusions at the 120d of treatment. Then those samples were transferred to 20°C and 40 μmol photons m-2·s-1 condition for recovery cultivation, after about 10 days, some recovery cells were observed in the thallus, and those cells developed to young thallus gradually and released germ cells almost in the same time. After about 60 days of recovery cultivation, the newly-grown green thallus broke through the original dead thallus, and the germ cells also grew to new individual thallus. Before dark treatment, the U. prolifera cells were filled with plastid, contained visible starch grain and discernible cell outlines, while after 120 days of dark treatment, the plastid shrank and degraded together with the disappearance of cell inclusions, and the cell outlines also blurred, then those samples were transferred to optimal culture conditions at 20°C in 40 μmol photons m-2·s-1 light intensity, and 15 days later, newly-grown cells appeared on the almost dead thallus, these cells divided continuously and grew to young thallus, and those newly-grown thallus also generated active germ cells, which developed to new thallus that cytologically identical to the original thallus. Observation of chopped tissue of U. prolifera cultivated at 20°C, 40 μmol m-2·s-1 showed that the morphological upper part cells turned to germ cells first, those germ cells including gametophyte and sporophyte, which released later and grew to new individual thallus. These findings provided cytological evidences for how U. prolifera live through stress conditions such as low temperature, darkness, and also useful for understanding the mechanism of the occurrence of green tide.

Circular RNA (circRNA) is a noncoding RNA that can regulate a variety of biological processes. CircRNAs can regulate gene expression posttranscriptionally by acting as microRNA sponges. Many turtle species are remarkable organisms due to their reproductive processes. However, information on circRNA in the gonads of turtles is limited. In this study, 6, 121 circRNAs were identified in the testes and ovaries of Chinese soft-shelled turtles (Pelodiscus sinensis) using the Illumina platform, and 710 circRNAs were significantly differentially expressed (DE). The DE circRNAs included 541 upregulated and 169 downregulated circRNAs in the testes. GO and KEGG pathway analysis indicated that the DE circRNAs were enriched in several signaling pathways, including GnRH, Wnt, FoxO, Progesterone mediated oocyte maturation, and mTOR signaling pathways. Five DE circRNAs were randomly selected, and their relative expression levels in ovaries and testes were detected by quantitative real-time PCR. All of these circRNAs were differentially expressed. In addition, 9, 883 interactions between circRNAs and miRNAs were predicted in the turtles. Target genes of the miRNAs include a range of genes regulating gonadal development. Seven ceRNA networks (DE circRNAs-DE miRNAs-DE mRNAs), including 7 DE circRNAs, 11 DE miRNAs and 20 DE mRNAs, were constructed. The networks included Cdc6, the miR-1 family, the miR-203 family, and the miR-302 family. The expression profile of gonadal circRNAs might help to elucidate the roles of nonprotein coding RNAs in turtle gonadal development.

Osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) plays an essential role in bone formation. Its imbalance can lead to osteoporosis. Estrogen and long noncoding RNAs (lncRNAs) have been confirmed to participate in osteogenesis. However, the underlying mechanism remains unclear. The purpose of our study was to explore the function of lncRNA H19 in estrogen-induced osteogenic differentiation of BMSCs. The present research demonstrated that the expression levels of lncRNA H19 and SIRT1 were markedly downregulated in postmenopausal osteoporosis (PMOP), while miR-532-3p expression was obviously increased. Moreover, estrogen induced the osteogenic differentiation of BMSCs by upregulating lncRNA H19. Furthermore, our integrated experiments showed that lncRNA H19 caused a decrease in the expression of miR-532-3p, which was verified to target SIRT1 directly. Additionally, estrogen alleviated osteoporosis in OVX rats through lncRNA H19-mediated miR-532-3p/SIRT1 axis. Our findings imply that lncRNA H19 mediates estrogen-regulated osteogenic differentiation in BMSCs via miR-532-3p/SIRT1 signalling and may become a novel target for alleviating PMOP.

Calcified coccoid fossils in the Permian-Triassic boundary microbialites were widely considered to represent the remains of the organisms that formed the microbialites. However, this role has been recently attributed to the fossil casts of Microcystis cyanobacterial colonies, leaving the ecological role of the coccoid fossils, as well as their affinities, uncertain. Here we propose that these coccoid fossils bear morphological similarity and are related to the extant epiphytic cyanobacterium Stanieria, and that they lived in surface waters by attaching themselves to bloom-forming phytoplankton, in a hitch-hiking lifestyle. Calcification of the envelopes of these interpreted Stanieria cells produced the small thin-walled spherical calcareous coccoid fossils. Different from ordinary pseudoplanktons, Stanieria cells cannot attach themselves to sparse plankton, but only to densely packed phytoplanktons in bloom. The dependence of these calcified Stanieria fossils on this lifestyle makes them possible indicators of ancient planktonic blooms. (C) 2015 Elsevier B.V. All rights reserved.

The establishment of safe and effective methods for controlling fungal disease is an urgent issue in agriculture and forestry. Microbiological control of plant disease is expected to achieve better results than use of chemically derived fungicides. This study aimed to establish Brevibacillus laterosporus JX-5 as a potential microbiological control agent of poplar canker. The bacterium was isolated from the poplar rhizosphere and demonstrated significant growth inhibition of several pathogenic fungi in vitro. The antifungal components of Br. laterosporus JX-5 were isolated and identified. The fermentation broth of Br. laterosporus JX-5 and its main antifungal component, designated as component B, reduced Botryosphaeria dothidea associated canker of the excised poplar branch by 70 and 90%, respectively. Component B is considerably heat-stable, adaptable to a broad pH range, and UV-resistant. It could inhibit Bo. dothidea by permeating the fungal membrane, fracturing the nuclei, damaging the cell wall, and eventually killing the pathogenic fungus. The antifungal activity exhibited by Br. laterosporus JX-5 and its bioactive metabolic products indicate its feasibility as a potential biocontrol agent for plant diseases.

Antimicrobial peptides are promising anti-infective agent candidates because they have a broad antimicrobial spectrum and bioactivity and are unlikely to elicit antibiotic resistance. The bogorols represent a new cationic antibiotic peptide and possess great therapeutic potential because of their bioactivity and precise mode of action. Here, we report that Bogorol B-JX (BBJX), a peptide previously isolated from Brevibacillus laterosporus JX-5 by us, has significant antibacterial and antitumor activities in vitro. BBJX was found to inhibit methicillin-resistant Staphylococcus aureus (MRSA) at 2.5 µg/mL with distinct mechanisms of action from those against Bacillus bombyseptieus and Escherichia coli. It penetrates MRSA membrane with little visible destruction and binds to genomic DNA. BBJX could inhibit the proliferation of human histiocytic lymphoma cell line U-937 and ConA-activated spleen cells at 5 µg/mL, but was not cytotoxic to the Jurkat cells, resting spleen cells or differentiated macrophage-like U-937 immunocytes. Moreover, BBJX caused apoptosis of U-937 cells by opening the mitochondrial permeability transition pore and stimulating the production of reactive oxygen species. Taken together, these studies provided basis for future medical application of the bogorols.

Plant growth promoting rhizobacteria (PGPR) for perennial apple trees (PAT) and apple tree saplings under continuous cropping (ATS) from two places in China were isolated and analyzed, and cluster analysis of BOX-PCR data was performed. The results showed that the quantities of both total rhizobacteria and the four kinds of PGPR (nitrogen-fixing bacteria, phosphate-solubilizing bacteria, silicate bacteria and antagonistic bacteria) from PAT were higher than those of ATS at different sampling points. The largest dissimilitude of BOX-PCR patterns for the PGPR indicated the genetic evolutionary distance of bacteria isolates was closer for the same sampling point. The shared cluster groups of the same variety of PGPR from two kinds of apple rhizosphere or different sampling points were very few. The diversity index, richness index and evenness index of PGPR from PAT were higher than those of ATS at both sampling points, while the dominance index was lower. The amounts and varieties of PGPR significantly changed between the PAT and ATS from different areas, which indicated the PGPR of the same plant varied from place to place due to the different environmental conditions. These results indicate that PGPR from PAT have the advantage of species diversity compared with ATS.

This study aims to assess the effects of copper exposure on hatching status and antioxidant defense at different stages of embryos and larvae of goldfish Carassius auratus . In this study, day-old embryos were randomly grouped after fertilization and then exposed to copper concentrations of 0, 0.1, 0.4, 0.7, and 1.0 mg L −1 . Copper-exposed fish embryos were sampled every 24 h to determine superoxide dismutase (SOD), and catalase (CAT) activities, as well as malondialdehyde (MDA) content. In addition, cumulative mortality and larval deformity were also investigated. The findings showed that cumulative mortality and larval deformity rate increased gradually with copper concentration increase. SOD and CAT activities were inhibited at higher copper concentrations. At a lower concentration (0.1 mg L −1 ), SOD activity increased in larvae, whereas CAT activity showed no significant change ( p > 0.05). MDA, as the lipid peroxidation product, gradually accumulated in embryos and larvae with increasing copper concentration and the extension of exposure time. At 0.4 mg L −1 and more, copper toxicity was shown in embryos and larvae. In conclusion, copper-exposed effects on hatching status and antioxidant defense in C. auratus embryos and larvae showed concentration- and time-dependent patterns. The biochemical parameters in this study can be used as effective indicators for evaluating the responses of copper-exposed fish embryos. In addition, this study demonstrates that 0.4 mg L −1 copper (corresponding to 1 mg L −1 copper sulfate), used to kill parasites in aquaculture, is not safe concentration, because it can result in toxicity to larvae. Therefore, the copper concentration to kill pathogen should be less than 0.4 mg L −1 for C. auratus .

To find a potential biocontrol agent against Fusarium sp. in apple seedlings, an endophytic bacterium strain was isolated from apple tree tissues. The inhibitive efficiency of the isolated strain against the hyphal growth of Fusarium sp. and Rhizoctonia solani was tested. Strain Y-1 showed significant inhibitory effects against Fusarium oxysporum, F. moniliforme, F. proliferatum, F. solani and R. solani. Its antifungal activity against F. oxysporum was the highest, reaching up to 64.90 %. In vivo tests indicated that strain Y-1 effectively protects apple from F. oxysporum infections. The control effect reached 92.26 % when bacterial inoculation was performed 3 days prior to pathogen inoculation. Strain Y-1 could colonize the rhizosphere and tissues within 30 days. It was also able to induce systemic resistance in apple seedlings as shown by the activities of SOD and POD. Strain Y-1 significantly increased the root length, root wet and dry weights, and plant height of the apple seedlings compared with the control group. The homology analysis of the 16S rRNA sequence, together with morphological, physical, and biochemical analyses, revealed that strain Y-1 is Bacillus subtilis.

The antagonist bacterium Brevibacillus laterosporus ZQ2 with broad-spectrum antifungal activity was isolated from an apple rhizosphere at Mount Tai in China. The fermentation medium for the production of antifungal substances from ZQ2 was statistically optimized. In one-factor-at-a-time experiments, five components, including carbon sources, nitrogen sources, and inorganic salt, were selected. Two factors were determined as critical based on the Plackett-Burman design. Steepest ascent experiments were then used to determine the design space containing the optimum point, followed by application of the response surface methodology. A quadratic model fitting the actual production was established using a central composite design. The obtained optimum medium for the antifungal substances production consisted of the following (in g/L): glucose, 15.6; soybean meal, 8.2; starch, 20; ammonium sulfate, 2; and monopotassium phosphate, 1. Furthermore, the inhibition rate of the substances against Rhizoctonia solani increased by more than 132% compared with the control. B. laterosporus ZQ2 strongly inhibited the growth of many apple phytopathogens in vitro. The inhibition rates against different fungi ranged from 55.26 to 79.02%. As well, the strain significantly reduced the disease damage caused by R. solani in the in vivo tests. Maximum disease protection (46.89%) was recorded when the bacterium applied 3 days before pathogen inoculation. Key words: Brevibacillus laterosporus, antifungal activity, fermentation optimization.

In this study, chlorophyll fluorescence parameters (∆F/F m′, F v/F m) and oxygen evolution of female vegetative tissues of Porphyra katadai var. hemiphylla in unisexual culture (FV) and in mixed culture with male vegetative tissues (FV-M) were followed at 5–20 °C, 10 and 80 μmol photons m−2 s−1. The formation of reproductive tissues was closely correlated with decreasing photosynthetic activities. At the same temperature the tissues cultured under 80 μmol photons m−2 s−1 showed a greater extent of maturation than those under 10 μmol photons m−2 s−1, and their decrease in photosynthesis was also larger. Under the same light intensity the extent of maturation increased with increasing temperature, and both cultures showed higher values of ∆F/F m′ and F v/F m at 10 and 15 °C, while their oxygen evolution became negative at 15–20 °C during the later period. Under the same culture condition the maturation of FV-M culture was relatively faster than that of FV culture, while their photosynthetic activity, especially ∆F/F m′, was lower.

Background The oriental river prawn (Macrobrachium nipponense) is the most prevalent aquaculture species in China. The sexual precocity in this species has received considerable attention in recent years because more and more individuals matured at a small size, which devalues the commercial production. In this study, we developed deep-coverage transcriptomic sequencing data for the ovaries of sexually precocious and normal sexually mature M. nipponense using next-generation RNA sequencing technology and attempted to provide the first insight into the molecular regulatory mechanism of sexual precocity in this species. Results A total of 63,336 unigenes were produced from the ovarian cDNA libraries of sexually precocious and normal sexually mature M. nipponense using Illumina HiSeq 2500 platform. Through BLASTX searches against the NR, STRING, Pfam, Swissprot and KEGG databases, 15,134 unigenes were annotated, accounting for 23.89% of the total unigenes. 5,195 and 3,227 matched unigenes were categorized by GO and COG analysis respectively. 15,908 unigenes were consequently mapped into 332 KEGG pathways, and many reproduction-related pathways and genes were identified. Moreover, 26,008 SSRs were identified from 18,133 unigenes. 80,529 and 80,516 SNPs were yielded from ovarian libraries of sexually precocious and normal sexually mature prawn, respectively, and 29,851 potential SNPs between these two groups were also predicted. After comparing the ovarian libraries of sexually precocious and normal sexually mature prawn, 549 differentially expressed genes (DEGs) and 9 key DEGs that may be related to sexual precocity of M. nipponense were identified. 20 DEGs were selected for validation by quantitative real-time PCR (QPCR) and 19 DEGs show consistent expression between QPCR and RNAseq-based differential expression analysis datasets. Conclusion This is the first report on the large-scale RNA sequencing of ovaries of sexually precocious and normal sexually mature M. nipponense. The annotated transcriptome data will provide fundamental support for future research into the reproduction biology of M. nipponense. The large number of candidate SNPs and SSRs detected in this study could be used as genetic markers for population genetics and functional genomics in this species. More importantly, many DEGs, especially nine key DEGs between sexually precocious and normal sexually mature prawns were identified, which will dramatically improve understanding of molecular regulatory mechanism of sexual precocity of this species.

This study assessed the impact of mercury exposure on goldfish (Carassius auratus) embryos based on the dynamic characteristics of chemical parameters. Day-old embryos were exposed to different Hg(2+) concentrations (0, 0.2, 1, 5, and 10 μg/L). Subsequently, the embryos were sampled every 24 h during embryonic development to measure acid phosphatase (ACP), alkaline phosphatase (AKP), lysozyme (LSZ), and catalase (CAT) activities, as well as malondialdehyde (MDA) content. The results revealed that the responses of ACP and AKP to mercury exposure presented in dose-dependent and time-dependent manners. The enzyme activities were significantly induced with increased concentrations and extended exposure (at 5 μg/L after 72 h and 10 μg/L after 48 h; p

The levels of photosynthetic pigments and chlorophyll fluorescence of Porphyra yezoensis strains selected from high-light environments were investigated. Sutong and Sulian strains originated from the same high-light environment but were selected from different sites on the Yellow Sea coast of Jiangsu Province, China. In January (a low temperature period), the Sulian strain and the WT (a widely cultivated strain) had higher levels of chlorophyll a, phycoerythrin, phycocyanin, and allophycocyanin, and higher actual photochemical efficiency of PSII (ΔF/F m′) than the Sutong strain. This indicated that Sulian and the WT may have better adaptation to low temperature. In March (an optimal temperature period), Sutong had higher levels of photosynthetic pigments and higher ΔF/F m′ than the WT and Sulian strains. This suggested that Sutong had higher light use efficiency at optimal temperatures and that most energy absorbed by PSII was used for photosynthetic electron transport. The differing areas of origin of these strains may have resulted in these differences in temperature adaptation.

Previous study has shown that Porphyra conchocelis is sensitive to high levels of PAR (400-700 nm) as well as ultraviolet radiation (UVR: 280-400 nm), resulting in high inhibition of photosynthesis. However, little is known about whether the inner covering layer of the shell, in which the conchocelis lives, may provide protection against solar UVR. Our study indicates that the covering calcareous matrix is about 0.06 mm thick, transmitting 63, 47, and 28% of PAR, ultraviolet radiation A (UVA: 315-400 nm), and ultraviolet radiation B (UVB: 280-315 nm), respectively. We used a shading layer that simulated the above transmissions, and the effective quantum yield of PSII and photosynthetic carbon fixation in the conchocelis increased to greater extents in the presence of UVA or UVB. Attenuation of UVA by 19% and UVB by 37% due to the shading layer increased the PSII yield by 44%-77% and photosynthetic carbon fixation by about 60%. Our study clearly shows that the photosynthetic machinery of Porphyra haitanensis T. J. Chang et B. F. Zheng conchocelis was efficiently protected from harmful UVR by the covering calcareous matrix.

Some conodonts described by Tea Kolar-Jurkovsek and Bogdan Jurkovsek (2007) from the Permian-Triassic boundary section in the Žiri area of western Slovenia are revised in this paper. One specimen that they assigned to Hindeodus parvus is tentatively regarded as Hindeodus cf. scalaris Wu 2005. Two specimens that they assigned to Isarcicella sp. A is changed to Hindeodus parvus. One specimen that they described as Isarcicella lobata Perri and Farabegoli is changed to Hindeodus crenatus Wu (2006). One specimen that they assigned to Isarcicella turgida (Kozur, Mostler and Rahimi-Yazd) is changed to Hindeodus cf. parvus. Since these revisions, the three conodont zones that they defined have been correspondingly revised. Their first zone may belong to Hindeodus parvus zone, but it is not certain. Their second zone is changed to the Hindeodus parvus zone, and their third one remains as is.

The microbial communities blooming immediately after the end-Permian mass extinction represent abnormally extreme environments, and vary in different areas. In this study, filamentous cyanobacterial biota was found in the strata after the extinction in the famous Permian-Triassic boundary section at Laolongdong, Chongqing, southwest China. In thin sections, the filamentous cyanobacterial fossils are below 1 mm in length, and generally taper to one end, with the widest diameter up to 0.08 mm. Some of them are curved, indicating that they are soft in life. Their walls are composed of cryptocrystalline to microcrystalline calcites. The filaments have round cross section, and are internally filled with micrites and fine sparry calcites, which indicate that the filaments are originally empty. They are randomly distributed in the rocks, but in some places, they tend to be distributed in radial pattern. The filamentous organisms are morphologically similar to Rivularia of Rivulariaceae, Cyanobacteria Phylum, but with calcified sheaths, and are tentatively regarded as an indeterminate new species in Rivularia: Rivularia sp. Cyanobacteria are photosynthetic autotrophic, and can survive in dysoxic condition. The blooming of this organism and the absence of other organisms may indicate that the environment was oxygendeficient and shallow, since this photosynthetic autotrophic organism needed to live within photic zone.

further reduced the yield by 53–55% in contrast to PAR alone treatment under solar radiation (UV-A of 33.2 W m 22 and UV-B of 0.85 W m 22 ) or a xenon lamp (UV-A of 25.5 W m 22 and UV-B of 1.15 W m 22 ). CO2 fixation was more reduced by UVR in the free-living vegetative (38%) than in the sporangial conchocelis (14%). Photosynthetic tolerance of UVR increased from vegetative to sporangial phase, then to thallus stage, correlating with the increased contents of UV-absorbing compounds and/or differentiated structure.

Spherical microfossils are present in the Hindeodus parvus zone of the Lower Triassic in Ziyun, Guizhou Province. They generally range from 0.15 to 0.30 mm across, with micritic wall and filled by micro-sparry calcites, and are evenly scattered in micritic matrix. Their abundance makes the rock assigned to microbialites. The accompanied organisms include ostracods and algal mat, but no gastropods or bivalves. Presence of small (

The eVects of ultraviolet radiation (UVR 280–400 nm) on the germination of Porphyra haitanensis conchospores and on the growth and morphogenesis of the subsequent sporelings were investigated by culturing the released conchospores under natural sunlight from 29 September to 6 October 2005. Germination increased with time and was faster when UV-Bwas excluded using cut-oV Wlters. There were signicant negative eVects of UV-B radiation on growth and cell division of sporelings, with decreases up to 18% for thallus length, between 6 and 18% for thallus width, up to 29% for thallus area, and between 6 and 14% for cell size as compared to PAR-controls. UV-A had a signicant positive eVect on morphogenesis, enhancing the formation of sporelings with cells dividing transversely; on the other hand, UV-B delayed the formation of such sporelings. We also tested the eVects of solar UVR on the growth of P. haitanensis juveniles and found no signiWcant eVects. Our results indicate that UV-A has an important role in the germination and morphogenesis of the species, but on the other hand, sporelings of P. haitanensis are more sensitive to UV-B radiation than juveniles. Fil: Jiang, Hongxia. Shantou University; China Fil: Gao, Kunshan. Shantou University; China Fil: Helbling, Eduardo Walter. Fundación Playa Unión. Estación de Fotobiología Playa Unión; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Studies of two Permian-Triassic boundary (PTB) sections on top of a Changhsingian reef in Ziyun, Guizhou Province, southwestern China indicate that the end-Permian mass extinction of reef ecosystems occurred in two steps. The first step is the extinction of all stenotropic organisms such as calcisponges and fusulinids in the latest Permian (in the Clarkina yini conodont zone). The biota after the first extinction is simple, comprising eurytropic organisms including microgastropods, ostracods, and some small burrowing organisms, or only algal mats. At the beginning of the Early Triassic (i.e. the beginning of the Hindeodus parvus zone), the environments became anoxic, and the microgastropod dominated biota or algal mats disappeared, which constituted the second episode of the mass extinction. The biota after the second extinction comprises small spherical microproblematica, some kinds of specialized organisms tolerant of anoxic or oxygen-poor conditions. As the environments became oxygenated, the specialized biota was replaced by a microgastropod-dominated simple biota. When the environmental conditions improved further, the simple biota was replaced by a diverse biota with normal-sized ammonoids, bivalves, and gastropods, representing restoration of normal oceanic conditions. Comparison with PTB sections in Dolomites, Italy and Meishan, Zhejiang Province shows that non-reef ecosystems had a similar first episode of mass extinction in the latest Permian. In the case that oceanic anoxia happened, non-reef ecosystems had a second extinction episode similar to that of reef ecosystems.

The toxicity of copper (Cu) on growth and activities of digestive and antioxidant enzymes in the hepatopancreas and intestine of juvenile Qihe crucian carp Carassius carassius was evaluated. The fish were exposed in different Cu solutions for 20 days, and the 0.60 mg/L group was then transferred to clean water to initiate a 20-day recovery period after Cu exposure. Results showed that all enzyme activities decreased significantly at high-concentration (0.30 and 0.60 mg/L) and long-time (20 days) Cu exposures and increased significantly at high-concentration (0.60 mg/L) and short-time Cu exposures (1 day). After the 20-day recovery period, all enzyme activities in the 0.60 mg/L group had recovered to control levels. High-concentration (0.60 mg/L) and long-time (20 days) Cu exposure markedly hindered the growth of fish, whereas the loss of fish growth can not be compensated for by a 20-day recovery period.

Fungi are important soil components as both decomposers and plant symbionts and play a major role in ecological and biogeochemical processes. However, little is known about the richness and structure of fungal communities. DNA sequencing technologies allow for the direct estimation of microbial community diversity, avoiding culture-based biases. We therefore used 454 pyrosequencing to investigate the fungal communities in the rhizosphere of Xinjiang jujube. We obtained no less than 40,488 internal transcribed spacer (ITS) rDNA reads, the number of each sample was 6943, 6647, 6584, 6550, 6860, and 6904, and we used bioinformatics and multivariate statistics to analyze the results. The index of diversity showed greater richness in the rhizosphere fungal community of a 3-year-old jujube than in that of an 8-year-old jujube. Most operational taxonomic units belonged to Ascomycota, and taxonomic analyses identified Hypocreales as the dominant fungal order. Our results demonstrated that the fungal orders are present in different proportions in different sampling areas. Redundancy analysis (RDA) revealed a significant correlation between soil properties and the abundance of fungal phyla. Our results indicated lower fungal diversity in the rhizosphere of Xinjiang jujube than that reported in other studies, and we hope our findings provide a reference for future research.

The end-Permian mass extinction was followed by the formation of an enigmatic rock layer with a distinctive macroscopic spotted or dendroid fabric. This deposit has been interpreted as microbial reef rock, digitate dendrolite, digital thrombolite, dendritic thrombolite, or bacterial deposits. Agreement has been reached in considering them as microbialites, but not in their formation. This study has revealed that the spotted and dendroid microbialites were composed of numerous fossil casts formed by the planktic cyanobacterium, Microcystis, a coccoid genus that at the present-day commonly forms blooms in modern lakes, rivers, and reservoirs. The abundance of the fossils and the diagenesis they experienced has determined the macroscopic fabric: where they abundant, the rock appears as dendroid, otherwise, it appears as spotted. The ancient Microcystis bloom might produce toxin to kill other metazoans, and be responsible for the oceanic anoxia that has puzzled so many researchers for so many years.

An antifungal Actinomyces BS-112 strain, with Aspergillus flavus as the target pathogen, was isolated from soil in the forest land of Mountain Tai. This strain showed a strong antagonistic activity against various mold fungi in food and feed. Strain BS-112 was identified as Streptomyces hygroscopicus based on its morphologic, cultural, physiological, biochemical characteristics, cell wall components and 16S rDNA sequence. Four active components were separated and purified from strain BS-112. These four antifungal components were identified as tetrins A and B and tetramycins A and B using spectroscopic analysis including mass spectrometry and nuclear magnetic resonance spectroscopy. Tetrins A and B and tetramycins A and B strongly inhibited the growth of A. flavus, A. alutaceus, A. niger, and A. fumigatus in vitro.

Three water-soluble polysaccharide fractions (PAP1-1, PAP1-2 and PAP2-1) were isolated and purified from the fruiting bodies of Pholiota adiposa by diethylaminoethanol (DEAE) Sepharose fast flow column and superdex TM 200 column chromatography on an AKTA Purifier system. Results of high-performance size-exclusion chromatography (HPSEC) indicated that the average molecular weights of PAP1-1, PAP1-2 and PAP2-1 were 2.3 x 10 6 Da, 8.8 x 10 3 Da and 2.1 x 10 6 Da, respectively. Monosaccharide compositions analysis revealed that PAP1-1 and PAP2-1 were both mainly composed of glucose, and PAP1-2 was composed of rhamnose and glucose with a mole ratio of 1:3.61. The evaluation of antioxidant activity suggested that PAP1-1 with β-configuration glycosidic bond exhibited stronger scavenging activity of superoxide radical and hydroxyl radical than PAP1-2 and PAP2-1 contained both α- and β-configuration glycosidic bond, and should be explored as a novel potential antioxidant. Available data obtained with in vitro models suggested that antioxidant activity of polysaccharide may be related to the configuration of glycosidic bond. Key words : Pholiota adipose , polysaccharide, purification, antioxidant activity.

In this study, the activities of SOD, CAT and GPX, and the contents of GSH and MDA in gill of grass carp, Ctenopharyngodon idellus, were measured to be used to explore the recovery changes of antioxidant defenses after short-period mercury exposure was removed. The results showed that the activities of SOD, CAT and GPX were significantly higher than those of the control after mercury exposure was just removed (p ;0.05). However, GSH content, compared with the control, was obviously lower on day 0 (p

The intertidal red alga Porphyra haitanensis Chang et Zheng is episodically desiccated and exposed to high levels of solar radiation at low tide during emersion. However, little has been documented on the relationship between the stresses during desiccation and related chemical compounds. We found that P. haitanensis thalli, when desiccated under indoor (artificial radiation) or outdoor (solar radiation) conditions, with or without UV radiation (UVR: 280-400 nm), contained significantly higher concentrations of UV-absorbing compounds (peak at 336 nm) than those maintained submerged (without desiccation). Solar UVR had no effect on the content of UV-absorbing compounds. Even though the concentration of these compounds decreased with time in all treatments, a slower decrease was observed in the desiccated samples. The samples with higher levels of UV-absorbing compounds showed higher photochemical efficiency of photosystem II (PS II) during the exposure or subsequent recovering process than samples with low concentration of UV-absorbing compounds, reflecting their protective role. The concentration of these compounds varied in different parts of the thallus, with the middle and marginal parts containing 60-80% more UV-absorbing compounds than the basal parts in both female and male plants. In addition, the marginal parts of male thalli contained more UV-absorbing compounds than the corresponding parts of female thalli. Our data suggest that desiccation plays a key role in this alga to maintain high concentration of UV-absorbing compounds, and that this might provide a beneficial advantage to compete in the intertidal zone where the organism is normally exposed to high levels of UVR. © 2007 Springer Science+Business Media B.V. Fil: Jiang, Hongxia. Changshu Institute Of Technology; China. Shantou University; China Fil: Gao, Kunshan. Shantou University; China. Xiamen University; China Fil: Helbling, Eduardo Walter. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión; Argentina