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More often than not, animals forage with other foragers present. A foraging game may take place when the outcome of a forager's actions depends on both its own and other foragers' strategies. Previous studies on predator-prey systems have verified that complex state-dependent foraging games exist between predators and prey. In this study, we looked for evidence of such a state-dependent foraging game between intra-guild competitors. We studied a desert rodent system featuring 2 coexisting species known to compete with each other: midday gerbils (Meriones meridianus, the dominant competitor) and 3-toed jerboas (Dipus sagitta, the subordinate competitor). We simultaneously manipulated the energetic states of both species and allowed them to forage and interact in arenas with artificial food patches. We found that both species responded to their own energetic states, whereas hungry jerboas also significantly responded to gerbils' energetic state in terms of food harvest. Gerbils preferred to carry food items away when foraging alone but switched to on-tray consumption when jerboas were present. Jerboas harvested more food when gerbils were hungry and the most intensive interference occurred when hungry jerboas encountered well-fed gerbils. A plausible explanation for these results is that the future rather than current value of cacheable food is more important to well-fed gerbils. In contrast, hungry gerbils prefer immediate consumption to completely excluding jerboas from resource patches. [ABSTRACT FROM AUTHOR]

* Premise of the study: Microsatellite markers were developed for a traditional fragrant flowering tree of China, Osmanthus fragrans, to investigate the genetic diversity of its wild populations and to facilitate the classification and identification of O. fragrans cultivars. * Methods and Results: Using the fast isolation by AFLP of sequences containing repeats (FIASCO) protocol, 29 primer sets were identified in two wild populations. All primer pairs displayed polymorphism. The number of alleles per locus ranged from two to eight, with a mean of 3.9. The expected and observed heterozygosities ranged from 0.125 to 0.932 and from 0.083 to 0.917, respectively. The transferability of the 29 primer pairs was tested on O. serrulatus, O. delavayi, and O. yunnanensis (three individuals for each species). Eighteen (62.1%), 16 (55.2%), and 21 (72.4%) of them were successfully amplified in O. serrulatus, O. delavayi, and O. yunnanensis, respectively. * Conclusions: These markers will facilitate further studies on the population genetics of O. fragrans and the classification and identification of O. fragrans cultivars. [ABSTRACT FROM AUTHOR]

In order to take advantage of the biorecognition between lectin and carbohydrate for targeted drug delivery, the lectin of peanut ( Arachis hypogaea ) agglutinin (PNA) was coupled by fixing its amino groups to the carbodiimide-activated carboxylic groups of 5-fluorouracil (5-Fu) derivative (N1-substituted 5-Fu acetate) to form 5-Fu-PNA conjugate. When the coupling reaction was carried out in the presence of d-galactose (d-gal, specific sugar for PNA), the affinity of PNA was maintained after its coupling to N1-substituted 5-Fu acetate, which was confirmed by the result of the haemagglutination test. Otherwise, PNA would lose its affinity after the cross-linking reaction. The cytotoxicity, specificity and selectivity of 5-Fu-PNA were examined on the human colorectal cancer cell line LoVo and the human normal liver cell line Chang using MTT assay. Compared with free drug, the active conjugate, which maintained the affinity of lectin, had similar cytotoxic effect on LoVo cells with much lower cytotoxicity on Chang cells On the other hand, lower cytotoxic effects on LoVo cells were observed for the non-active conjugate even at higher drug concentrations. The cytotoxic effect of conjugate was specific because only the active conjugate could inhibit the growth of LoVo cells in a dose- and time-dependent manner as that of the free drug. The achieved results indicate the significance to maintain the affinity of lectin for lectin-mediated cytotoxicity. Still, the potential of 5-Fu-PNA conjugate as a targeting agent for colorectal cancer needs to be further investigated in vivo . [ABSTRACT FROM AUTHOR]

• Premise of the study: Corallodiscus is widespread across China and in adjacent countries to the west and south, with C. lanuginosus covering the entire range of the genus. Microsatellite markers will be useful to address within-complex taxonomic and biogeographic structures of this species. • Methods and Results: Fourteen markers were developed using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) protocol. Polymorphism was assessed in 12 individuals each from two populations from West Yunnan, China. Nine primers displayed polymorphisms. The number of alleles per locus ranged from one to six (mean: 2.7). The observed and expected heterozygosities ranged from 0 to 1 and from 0 to 0.772 (average: 0.487 and 0.448). Only one of the polymorphic loci deviated from Hardy-Weinberg equilibrium. Among the four congeneric species, cross-amplification success ranged from two to eight markers. • Conclusions: The markers will be useful for population genetic and evolutionary history studies for C. lanuginosus and the allied species C. bhutanicus , C. cooperi , and C. kingianus [ABSTRACT FROM AUTHOR]

* Premise of the study: Microsatellite primers were developed in the strongest and most economically important bamboo species, Dendrocalamus sinicus, to investigate its genetic variability. * Methods and Results: Using the Fast Isolation by AFLP of Sequences Containing Repeats (FIASCO) protocol, 16 polymorphic primer sets were identified within 24 individuals from two geographic locations. The number of alleles per locus ranged from two to four, with a mean of 2.6. The observed and expected heterozygosities varied from 0 to 1.000 and from 0.311 to 0.754, respectively. The cross-amplification of the 16 primer pairs was tested in four other Dendrocalamus species, and nine to 13 (56.3-81.3%) primer pairs were successfully amplified. * Conclusions: These markers will be useful for studies on the genetic diversity of D. sinicus, which may facilitate conservation of this species. [ABSTRACT FROM AUTHOR]

Premise of the study: Microsatellite primers were developed in the traditional Tibetan medicinal plant Halenia elliptica D. Don to investigate its genetic diversity and population genetic structure. Methods and Results: Using the Fast Isolation by AFLP of Sequences Containing (FIASCO) repeats protocol, 24 primer sets were identified in two wild populations. Of these primers, 12 displayed polymorphisms and 12 were monomorphic. The number of alleles per locus ranged from 2 to 6, with a mean of 3.9. The expected ( HE ) and observed ( H O ) heterozygosities ranged from 0.191 to 0.784 and from 0.417 to 0.917, respectively. All these primers successfully amplified in two close relatives of H. elliptica , Swertia bimaculata (Siebold & Zucc.) Hook. f. & Thomson ex C. B. Clarke and S. tetraptera Maxim. Conclusions : These markers will facilitate further studies on the population genetics of Halenia elliptica and its allied species. [ABSTRACT FROM AUTHOR]

* Premise of the study: Microsatellite makers were developed for Clematoclethra scandens to investigate its population genetics and speciation. *Methods and Results: A total of 36 microsatellite markers were isolated using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) method. Their polymorphisms were assessed in two natural populations. The results showed that 30 markers displayed prominent polymorphisms and six markers were monomorphic. * Conclusions: These microsatellite loci will facilitate further studies on population genetics and speciation of C. scandens [ABSTRACT FROM AUTHOR]

Thymopentin (Tp5) was loaded in poly-butylcyanoacrylate (PBCA) nanoparticles (NP) in order to enhance the oral bioavailability of Tp5. PBCA-Tp5-NP was prepared by nanoprecipitation methods. Dialyzing membrane method was employed to examine the in vitro release of PBCA-Tp5-NP in PBS, and Tp5 samples in the release medium were detected by HPLC. The cell proliferation test (3H-thymidine) was conducted to verify the PBCA-Tp5-NP bioactivity in vitro. The pharmacodynamical studies were performed on preimmunoinhibited rats and in flow cytometer. The size and the entrapment efficiency of PBCA-Tp5-NP were 178 ± 39 nm and 92.21 ± 1.08%, respectively. In vitro release data show that less than 60% Tp5 was released from lyophilized PBCA-Tp5-NP while 80% Tp5 was released from the colloidal PBCA-Tp5-NPs in 48 h. The proliferation test showed that PBCA-Tp5-NP had the similar effect as Tp5. The in vivo data showed that oral PBCA-Tp5-NPs had similar function as what intravenous Tp5 did. The oral bioavailability of Tp5 could be enhanced by PBCA nanoparticles. PBCA-Tp5-NP had the property of sustained-release and the efficacy of Tp5 was not changed after formulation. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:2249–2258, 2008 [ABSTRACT FROM AUTHOR]

The former genus Bournea is endemic to China, including two species, has been under consideration for incorporation into the expanded genus Oreocharis s.l. in Gesneriaceae. The phylogenetic tree inferred from two DNA sequences (trnL-F and ITS) showed that this genus is deeply nested into Oreocharis s.l. However, the new tree from seven ones (atpB-rbcL, ndhH-rps15-ycf1, rpl132, trnC-trnD, trnL-F, trnTtrnL of chloroplast DNA and ITS regions) revealed that Bournea is the sister group of other of Oreocharis s.l. Furthermore, Bournea is morphologically different from other Oreocharis based on existing data. We suggest keeping Bournea as an independent genus in Gesneriaceae. [ABSTRACT FROM AUTHOR]

Gentianella macrosperma Ma ex H.F. Cao, J.D. Ya & Q.R. Zhang, a new species of Gentianaceae from Xinjiang, Northwest China is described and illustrated. This new species is unique in having equal length of corolla lobe and corolla tube, nectaries located at the throat of the corolla tube and large seeds up to 1.6 mm in diameter. In addition, an updated identification key to the Chinese species of Gentianella is provided. [ABSTRACT FROM AUTHOR]

Theoretical analysis for an online measurement of the stack gas flow velocity based on the optical scintillation method with a structure of two parallel optical paths is performed. The causes of optical scintillation in a stack are first introduced. Then, the principle of flow velocity measurement and its mathematical expression based on cross correlation of the optical scintillation are presented. The field test results show that the flow velocity measured by the proposed technique in this article is consistent with the value tested by the Pitot tube. It verifies the effectiveness of this method. Finally, by use of the structure function of logarithmic light intensity fluctuations, the theoretical explanation of optical scintillation spectral characteristic in low frequency is given. The analysis of the optical scintillation spectrum provides the basis for the measurement of the stack gas flow velocity and particle concentration simultaneously. [ABSTRACT FROM AUTHOR]

Background: Cymbidium orchids, including some 50 species, are the famous flowers, and they possess high commercial value in the floricultural industry. Furthermore, the values of different orchids are great differences. However, species identification is very difficult. To a certain degree, chloroplast DNA sequence data are a versatile tool for species identification and phylogenetic implications in plants. Different chloroplast loci have been utilized for evaluating phylogenetic relationships at each classification level among plant species, including at the interspecies and intraspecies levels. However, there is no evidence that a short sequence can distinguish all plant species from each other in order to infer phylogenetic relationships. Molecular markers derived from the complete chloroplast genome can provide effective tools for species identification and phylogenetic resolution. Results: The complete nucleotide sequences of eight individuals from a total of five Cymbidium species' chloroplast (cp) genomes were determined using Illumina sequencing technology of the total DNA via a combination of de novo and reference-guided assembly. The length of the Cymbidium cp genome is about 155 kb. The cp genomes contain 123 unique genes, and the IR regions contain 24 duplicates. Although the genomes, including genome structure, gene order and orientation, are similar to those of other orchids, they are not evolutionarily conservative. The cp genome of Cymbidium evolved moderately with more than 3% sequence divergence, which could provide enough information for phylogeny. Rapidly evolving chloroplast genome regions were identified and 11 new divergence hotspot regions were disclosed for further phylogenetic study and species identification in Orchidaceae. Conclusions: Phylogenomic analyses were conducted using 10 complete chloroplast genomes from seven orchid species. These data accurately identified the individuals and established the phylogenetic relationships between the species. The results reveal that phylogenomics based on organelle genome sequencing lights the species identification-organelle-scale "barcodes", and is also an effective approach for studying whole populations and phylogenetic characteristics of Cymbidium. [ABSTRACT FROM AUTHOR]

Embryo implantation into the maternal uterus is a crucial step for the successful establishment of mammalian pregnancy. Following the attachment of embryo to the uterine luminal epithelium, uterine stromal cells undergo steroid hormone-dependent decidualization, which is characterized by stromal cell proliferation and differentiation. The mechanisms underlying steroid hormone-induced stromal cell proliferation and differentiation during decidualization are still poorly understood. Ribonucleotide reductase, consisting of two subunits (RRM1 and RRM2), is a rate-limiting enzyme in deoxynucleotide production for DNA synthesis and plays an important role in cell proliferation and tumorgenicity. Based on our microarray analysis, Rrm2 expression was significantly higher at implantation sites compared with interimplantation sites in mouse uterus. However, the expression, regulation, and function of RRM2 in mouse uterus during embryo implantation and decidualization are still unknown. Here we show that although both RRM1 and RRM2 expression are markedly induced in mouse uterine stromal cells undergoing decidualization, only RRM2 is regulated by progesterone, a key regulator of decidualization. Further studies showed that the induction of progesterone on RRM2 expression in stromal cells is mediated by the AKT/c-MYC pathway. RRM2 can also be induced by replication stress and DNA damage during decidualization through the ATR/ATM-CHK1-E2F1 pathway. The weight of implantation sites and deciduoma was effectively reduced by specific inhibitors for RRM2. The expression of decidual/trophoblast prolactin-related protein (Dtprp), a reliable marker for decidualization in mice, was significantly reduced in deciduoma and steroid-induced decidual cells after HU treatment. Therefore, RRM2 may be an important effector of progesterone signaling to induce cell proliferation and decidualization in mouse uterus. [ABSTRACT FROM AUTHOR]

Background: Delayed implantation is a developmental arrest at the blastocyst stage and a good model for embryo implantation. MicroRNAs (miRNAs) have been shown to be involved in mouse embryo implantation through regulating uterine gene expression. This study was to have an integrative analysis on global miRNA and mRNA expression in mouse uterus under delayed implantation and activation through Illumina sequencing. Methodology/Principal Findings: By deep sequencing and analysis, we found that there are 20 miRNAs up-regulated and 42 miRNAs down-regulated at least 1.2 folds, and 268 genes up-regulated and 295 genes down-regulated at least 2 folds under activation compared to delayed implantation, respectively. Many different forms of editing in mature miRNAs are detected. The percentage of editing at positions 4 and 5 of mature miRNAs is significantly higher under delayed implantation than under activation. Although the number of miR-21 reference sequence under activation is slightly lower than that under delayed implantation, the total level of miR-21 under activation is higher than that under delayed implantation. Six novel miRNAs are predicted and confirmed. The target genes of significantly up-regulated miRNAs under activation are significantly enriched. Conclusions: miRNA and mRNA expression patterns are closely related. The target genes of up-regulated miRNAs are significantly enriched. A high level of editing at positions 4 and 5 of mature miRNAs is detected under delayed implantation than under activation. Our data should be valuable for future study on delayed implantation. [ABSTRACT FROM AUTHOR]

Microparticles containing solid lipid nanoparticles (SLNs) are receiving increased attention as carriers for the lung delivery of the SLNs. Thus, we aim to prepare the hybrid microparticles and thoroughly evaluate their feasibility for the pulmonary drug delivery. The microparticles were prepared by co-spray-drying the thymopentin (TP5)-loaded SLNs with bulking agents. Thereafter, we systematically estimated the potential of the microparticles as the carriers for the pulmonary delivery of the SLNs, including the investigations of their characteristics, aerodynamic properties, pharmacokinetics and pharmacodynamics. The spherical and hollow microparticles presented a size of 4.1 ± 0.1 μm and a low tap density of 0.175 ± 0.02 g/cm3. In addition, the microparticles showed a high aerosolization efficiency (emitted dose of 98.0% ± 1.23% and respirable fraction of 51.07% ± 1.21%). Furthermore, the SLNs could be easily recovered from the microparticles without essential changes on their characteristics and the drug release behavior. The pharmacokinetic and pharmacodynamic studies suggested that, compared to i.v. TP5 solution, the bioavailability and therapeutic efficacy of TP5 were remarkably strengthened after the pulmonary administration of the microparticles. Taken together, we believe the microparticles were suitable for inhalation and possesed an ample potential for the pulmonary delivery of the SLNs. [ABSTRACT FROM AUTHOR]

A major goal for gene therapy is to obtain targeted vectors that transfer genes efficiently to specific cell types. The liver possesses a variety of characteristics that make this organ very attractive for gene therapy. In the present study, four cholesterylated thiogalactosides 1a?~?d with different spacer length were synthesized to formulate novel lipid-polycation-DNA (LPD) complexes, which were composed of galactosylated cationic liposomes, protamine sulfate and plasmid DNA. The galactosylated LPD1c significantly improved the levels of gene expression in cultured hepatoma cells HepG2 and SMMC-7721, while LPD1a and LPD1b did not significantly improve the levels compared with non-galactosylated LPD. Meanwhile, increased transfection activity was not observed in mouse fibroblasts L929 for galactosylated LPDs. Cytotoxicity of galactosylated LPDs assay showed they had no obvious toxicities to L929 cells and HepG2 cells. In summary, the length of the spacer between the anchor and galactose residues was important for the recognition of asialoglycoprotein receptor. The LPD1c described here, combining the condensing effect of protamine and the targeting capability of cholesterylated thiogalactosides, are potentially useful gene carriers to liver parenchymal cells. [ABSTRACT FROM AUTHOR]