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Phylogeographic investigation on the spiny frog Quasipaa shini (Amphibia: Anura: Dicroglossidae) using mitochondrial DNA: cryptic species and species complex
No full textThe spiny-flanked frog Quasipaa shini is distributed in southcentral China. Here, phylogenetic relationships and diversification of the species were examined using mitochondrial COI gene sequences of 70 individuals from eight populations. Phylogenetic analyses revealed that the species contained two deeply divergent clades (Clades I and II) and five subclades in Clade II. Haplotype network, AMOVA and genetic distance estimations also supported the separations of the six phylogroups. Based on the results, we proposed that at least the Clade I should represent a cryptic species. Neutrality tests indicated that all populations and clades have been probably suffered bottleneck effects or subdivisions
Identifying Intraspecific Variation in Venom Yield of Chinese Cobra (Naja atra) from Ten Populations in Mainland China
Full text linkDetailed information on venom yield is helpful in preparing antivenoms and treating snakebites, but such information is lacking for many species of venomous snakes. The Chinese cobra (Naja atra) is a large sized, venomous snake commonly found in southeastern China, where it causes a heavy burden of snakebites. To examine the effects of various factors (morphology, sex, age, season, and geographical origin) on the venom yield in this snake, we collected venom samples of 446 individuals (426 adults and 20 neonates) from 10 populations of N. atra over an eight-year period. We used two variables, lyophilized venom mass (venom yield) and solid content of venom (% solids), to quantify the venom yield. We used linear regression analysis to check if venom yield was related to morphological factors, one-way ANOVA and one-way ANCOVA to detect the sexual, ontogenetic, and geographic variation in venom yield, and repeated-measures ANOVA to examine seasonal shifts in venom yield. Our results indicate that venom yield of N. atra is positively related to the morphological traits examined, with male snakes expelling more venom than females. Venom yield in N. atra was age-related, with elder snakes always expelling more venom than younger ones. Geographic variation in venom yield was also observed, while seasonal variation was not. The solid content of venom was lower in males than in females, but this was not related to morphology, season, age, or geography. Our findings suggest that venom yield in N. atra is influenced by multiple factors, as well as by the interactions among these factors
Legume plants may facilitate Zanthoxylum bungeanum tolerance to extreme rainfall
No full textA complete randomized design was implemented with two watering regimes (extreme rainfall and control) and three different plant combinations (Zanthoxylum bungeanum, Z. bungeanum + Capsicum annum, Z. bungeanum Glycine max) in order to assess the morphological and physio-biochemical responses of focal and neighbor plants. The results indicated that, extreme rainfall had significantly negative impacts on Z. bungeanum in three intercropping systems. However, intercropping with G. max improved the transpiration rate (T-r) and stomatal conductance (G(s)), raised leaf relative water content (LRWC), increased chlorophyll a (Chl a) and carotenoid (Car) content, and enhanced the superoxide dismutase activity (SOD) of Z. bungeanum. After recovery, the Z. bungeanum +/- G. max mixed culture significantly increased soil NO3--N, improved the intercellular carbon dioxide concentration (C-i) and T-r,T- upregulated soluble sugar and proline, and enhanced hydrogen peroxidase activity (CAT). Moreover, the higher root biomass of G. max provided much more nitrogen for Z. bungeanum via the return of organic matter. However, intercropping with C. annum significantly increased active oxygen (ROS). Compared with neighboring species, in intercropping systems, G. max could have improved the tolerance of the focal species Z. bungeanum in response to extreme rainfall and its recovery after extreme rainfall
Functional characterization of phenylalanine ammonia-lyase- and cinnamate 4-hydroxylase-encoding genes from Lycoris radiata, a galanthamine-producing plant
No full textGalanthamine (GAL), the well-known Amaryllidaceae alkaloid, is a clinically used drug for the treatment of Alzheimer's disease. L-Phenylalanine (Phe) and trans-cinnamic acid (CA) were enzymatically transformed into the catechol portion of GAL Herein, a Phe ammonia-lyase-encoding gene LrPAL3 and a cinnamate 4hydroxylase-encoding gene LrC4H were cloned from Lycoris radiata, a GAL-producing plant. LrPAL3 was overexpressed in Escherichia coli and purified to homogeneity. LrPAL3 catalyzes the forward deamination conversion of L-Phe into trans-CA. The 3-chloro- and 4-fluoro-L-Phe were deaminated to generate the corresponding 3-chloro- and 4-fluoro-trans-CA by LrPAL3. LrPAL3-catalyzed reverse hydroamination was confirmed by the conversion of trans-CA into L-Phe with exceptional regio- and stereo-selectivity. LrC4H was overexpressed in E. coli with tCamCPR, a cytochrome P450 reductase-encoding gene. LrC4H catalyzes the regioselective parahydroxylation on trans-CA to form p-coumaric acid. The transcriptional levels of both LrPAL3 and LrC4H were positively associated with the GAL contents within the leaves and flowers of L radiata, which suggested that their expression and function are co-regulated and involved in the biosynthesis of GAL The present investigations on the biosynthetic genes of GAL will promote the development of synthetic biology platforms for this kind of important drug via metabolic engineering. (C) 2018 Elsevier B.V. All rights reserved
High altitude species, high profits: Can the trade in wild harvested Fritillaria cirrhosa (Liliaceae) be sustained?
No full textEthnopharmacological relevance: Fritillaria cirrhosa D. Don bulbs contain alkaloids and are one of the most intensively exploited alpine Himalayan medicinal species. In terms of proprietary medicines, our study shows that 210 F. cirrhosa products are offered by 46 suppliers, most of which (44) are situated in China and two in Nepal. A widespread commercial use is as one of the main ingredients in cough syrups. A well known example is "Nin Jiom Pei Pa Koa Herbal Cough & Throat Syrup", which typically contains more F. cirrhosa than any other herbal ingredient in the formulation. The biggest market for F. cirrhosa bulbs is China, where demand exceeds supply of this wild harvested species for use in traditional Chinese medicine (TCM). Cross-border trade from Nepal to China occurs in significant quantities. Bhutan also imports F. cirrhosa bulbs from Nepal. In addition, F. cirrhosa is registered as an active ingredient in traditional herbal medicinal preparations in Australia, Canada, Hong Kong SAR, Malaysia, Republic of Korea, Singapore and Taiwan. There is also an export trade in F. cirrhosa to Europe. Assessing how much F. cirrhosa is traded is complex, however, due to a "look-alike" challenge, as nine Chinese Fritillaria species are traded in Europe (Fritillaria cirrhosa, F. delavayi, F. hupehensis, F. pallidiflora, F. przewalskii, F. thunbergii, F. unibracteata, F. ussuriensis and F. walujewii). Aims of the study: The aims of this review were to assess the scale of the global trade in F. cirrhosa, and to synthesise studies of the impacts of wild harvest on F. cirrhosa populations and on the extent of emerging cultivation initiatives as an alternative to wild harvest. Methods: Firstly, we reviewed published information on studies on impacts of wild F. cirrhosa harvest from across the geographic range of this species. Secondly, global trade data for F. cirrhosa were analysed. Results: The principal demand for F. cirrhosa bulbs is in China, where hundreds of different companies produce Fritillaria preparations. Trade data also show that in 2013, China exported over 44 tonnes of F. cirrhosa bulbs to Taiwan and 26.7 tonnes to the Republic of Korea. Extensive commercial use and limited wild stocks result in a high price (2000 - 3800 CNY per kg (around US60 in 2002 to US$560 per kg in 2017. To date, cultivation has been unable to meet the entire market demand for F. cirrhosa bulbs, although other Fritillaria species are successfully cultivated on a larger scale
A molecular phylogenetic hypothesis for the Asian agamid lizard genus Phrynocephalus reveals discrete biogeographic clades implicated by plate tectonics
No full textPhylogenetic relationships of the agamid lizard genus Phrynocephalus are described in the context of plate tectonics. A near comprehensive taxon sampling reports three data sets: (1) mitochondrial DNA from ND1 to COI (3' end of ND1, tRNA(Gln), tRNA(ll)(e), tRNA(met), ND2, tRNA(T)(rP), tRNA(Ala), tRNA(A)(sn), tRNA(C)(Ys), tRNA(T)(Yr), and the 5' end of COI) with 1761 aligned positional sites (1595 included, 839 informative), (2) nuclear RAG-1 DNA with 2760 aligned positional sites (342 informative), and (3) 25 informative allozyme loci with 213 alleles (107 informative when coded as presence/absence). It is hypothesized that Phrynocephalus phyletic patterns and speciation reflect fault lines of ancient plates now in Asia rejuvenated by the more recent Indian and Arabian plate collisions. Molecular estimates of lineage splits are highly congruent with geologic dates from the literature. A southern origin for the genus in Southwest Asia is resolved in phylogenetic estimates and a northern origin is statistically rejected. On the basis of monophyly and molecular evidence several taxa previously recognized as subspecies are recognized as species: P hongyuanensis, P. sogdianus, and P strauchi as "Current Status"; Phrynocephalus bannikovi, Phrynocephalus longicaudatus, Phrynocephalus turcomanus, and Phrynocephalus vindumi are formally "New Status". Phylogenetic evaluation indicates a soft substrate habitat of sand for the shared ancestor of modern Phrynocephalus. Size diversity maximally overlaps in the Caspian Basin and northwestern Iranian Plateau. The greatest species numbers of six in sympatry and regional allopatry are found in the southern Caspian Basin and southern Helmand Basin, both from numerous phylogenetic lineages in close proximity attributed to tectonic induced events
Detection and Categorization of Diarrheagenic Escherichia coli with Auto-microfluidic Thin-film Chip Method
No full textDiarrheagenic Escherichia coli (DEC) causes human diarrhea symptom in both healthy and immunocompromised individuals. An auto-microfluidic thin-film chip (AMTC) instrument integrating one-step multiplex PCR (mPCR) with reverse dot blot hybridization (RDBH) was developed for highthroughput detection of DEC. The novel mPCR method was developed by designing 14 specific primers and corresponding probes. 14 indexes including an endogenous gene (uidA) and 13 pathogenic genes (stx1, stx2, escV, ipaH, invE, estB, lt, pic, aggR, astA, bfpB, sth and stp) of DEC were detected. This one-step mPCR + RDBH approach is useful for simultaneous detection of numerous target genes in a single sample, whose specificity and availability have been confirmed on the positive control of 11 DEC strains. In addition, with 300 diarrheal stool samples being detected by this method, 21 were found to contain five major DEC strains. Compared with monoplex PCR and previous one-step mPCR approach, this method could detect ipaH and estB, and compared with current commercial kit, the relevance ratio of DEC detected by the AMTC method was increased by 1% in stool samples. Furthermore, the novel integration AMTC device could be a valuable detection tool for categorization of E. coli
Effects of Pseudomonas chenduensis and biochar on cadmium availability and microbial community in the paddy soil
No full textThe cadmiumcontamination in the paddy soil results in serious environmental pollutions. In situ soil remediation based on the applications of additives such as functional microorganisms and biochars has gradually attained more attentions. However, how these exogenous additives affect the local microbial communities is less discussed. In this study, a heavy metal resistant bacterium (Pseudomonas chenduensis, strain MBR) and biochar derived from oil palm fibers were separately added into the simulated Cd-contaminated paddy soil to investigate the roles of these additives in the soil remediation and regulating local microbial community. The results showed that compared with control, the addition of the strain MBR and biochar reduced the exchangeable/acid soluble cadmium fraction by 30% and 18%, respectively. Moreover, higher microbial diversity, more deterministic effects and less variation in microbial community were observed in the treatments supplemented with the strain MBR and biochar, and the increase of the deterministic effects on microbial interactions was demonstrated by network analysis further. Additionally, the abundance of the strain MBR in the paddy soil decreased as time passed, which maximally decreased the disturbance for the local micro-ecological niche and ensured ecological security. These results showed that two additives supplementation, in particular Pseudomonas chenduensis, can significantly decrease cadmium availability, contributing to the reduction of the disturbance on soil microbial community and maintaining microbial stability under cadmium pressure. It highlights a new criterion referred to microecology for the evaluation of the roles of additives in local soil remediation. (c) 2018 Elsevier B.V. All rights reserved
Temporal shifts in controls over methane emissions from a boreal bog
No full textWe measured year-round landscape-scale methane (CH4) flux in a boreal bog from May 2014 to April 2016 using the eddy covariance technique. The objectives of the study were to investigate the controls on CH4 flux at different periods of the growing season and to quantify the annual CH4 flux budget. The daily average growing season water table (WT) ranged from -0.33 to - 0.08 m in 2014 and from -0.36 to - 0.08 m in 2015. Strong seasonal variability in the daily average CH4 fluxes was observed in both 2014 and 2015, ranging from near zero before May to a peak of above 20 nmol m(-2) s(-1) in the middle-late August in 2014 and in the early-middle September in 2015. Soil temperature at 50 cm and water table exerted interactive impact on the seasonal variation in the daily average growing season CH4 flux in both years. Soil temperature at 1 cm was negatively related to CH4 flux when water table dropped more than 0.25 m below the peat surface in 2015 growing season, suggesting that the seasonal variation in CH4 flux was dominated by the variation due to CH 4 oxidation. During the non-growing season, the daily variation in CH4 fluxes was mostly related to friction velocity in both years. In addition, daily average CH4 flux was linearly related to net ecosystem exchange of CO2 (NEE) when daily NEE was negative (Le., days with CO2 uptake larger than ecosystem respiration), but there was no correlation between them when NEE was positive (days with ecosystem respiration dominated over CO2 uptake) during the growing season. We found that this boreal bog acted as a small CH4 source of 3.7 +/- 0.9 g CH4 m(-2) from May 2014 to April 2015 and 3.1 +/- 0.9 g CH4 m(-2) from May 2015 to April 2016. These values were at the lower end of the range of CH4 emission rates reported for boreal peatlands. Non-growing season CH4 emissions accounted for 41% (the first study year) and 39% (the second study year) of the annual emissions, highlighting the importance of non-growing season CH4 emissions in estimating the annual CH4 budget and the feedback to climate
Effect of taste masking technology on fast dissolving oral film: dissolution rate and bioavailability
No full textFast dissolving oral film is a stamp-style, drug-loaded polymer film with rapid disintegration and dissolution. This new kind of drug delivery system requires effective taste masking technology. Suspension intermediate and liposome intermediate were prepared, respectively, for the formulation of two kinds of fast dissolving oral films with the aim of studying the effect of taste masking technology on the bioavailability of oral films. Loratadine was selected as the model drug. The surface pH of the films was close to neutral, avoiding oral mucosal irritation or side effects. The thickness of a 2 cm x 2 cm suspension oral film containing 10 mg of loratadine was 100 pm. Electron microscope analysis showed that liposomes were spherical before and after re-dissolution, and drugs with obvious bitterness could be masked by the encapsulation of liposomes. Dissolution of the two films was superior to that of the commercial tablets. Rat pharmacokinetic experiments showed that the oral bioavailability of the suspension him was signihcantly higher than that of the commercial tablets, and the relative bioavailability of the suspension him was 175%. Liposomal him produced a certain amount of improvement in bioavailability, but lower than that of the suspension him