Water-Swellable Cellulose Nanofiber Aerogel for Control of Hemorrhage from Penetrating Wounds

Uncontrolled hemorrhage from wounds with deep and irregular cavities is short of efficient hemostats. Here we report a citric acid-cross-linked carboxymethyl cellulose nanofiber (CA-CMCNF) aerogel for the control of bleeding from penetrating wounds. The compressed CA-CMCNF aerogel could quickly swell into its original shape in water in seconds. The maximum mass and volume expansion ratios were over 6800 and 3000%, respectively. The water-swellable property allows the aerogel to self-expand and fill in the cavities of wounds. The in situ-generated expansion pressure resisted the systolic blood pressure, and the plentiful carboxyl groups triggered the active coagulation pathway, both contributing to the hemostatic capability of the aerogel. Additionally, the aerogel had good biocompatibility and excellent antibacterial capability. The animal experiments revealed that the aerogels significantly reduced both the hemostasis time and the amount of bleeding in a liver penetrating model. Therefore, this study provides a safe and robust hemostatic aerogel for controlling bleeding from penetrating wounds

AFLP-based genetic diversity of wild orchardgrass germplasm collections from Central Asia and Western China, and the relation to environmental factors

<div><p><i>Dactylis glomerata</i> L. (orchardgrass) is an important perennial forage species in temperate areas of the world. It is usually used for silage, grazing and hay because of its high nutritional value and reproducibility. Central Asia, Xinjiang and Tibetan Plateau in China possess various special micro-environments that harbor many valuable resources, while different degrees of degradation of the grassland ecosystem occurred due to climatic changing and human activities. Investigating the genetic diversity of wild <i>D</i>. <i>glomerat</i> could provide basis for collection, protection, and utilization of some excellent germplasm resources. Totally 210 individuals from 14 populations—five from Xinjiang, two from Kangding (Tibetan Plateau), and seven from Central Asia were identified using AFLP technology. The average values of Nei’s genetic diversity (<i>H</i>_<i>j</i>) and Shannon information index (<i>H</i>_<i>o</i>) were 0.383 and 0.394 respectively. UPGMA tree, STRUCTURE analysis and principal coordinate analysis (PCoA) showed populations from same region clustered together. AMOVA revealed 35.10% of the genetic differentiation (<i>F</i>_<i>st</i>) occurred among populations. Gene flow (<i>N</i>_<i>m</i>) was limited among all populations. Genetic diversity of <i>D</i>. <i>glomerata</i> was high but limited under isolation-by-distance pattern, resulting in high genetic differentiation and low gene flow among populations. Adjacent regions also exhibited similar results because of the barriers of high mountains. The environmental factors, such as precipitation, elevation, latitude and longitude also had some impacts on genetic diversity and structure pattern of populations.</p></div

Geographical locations of analyzed populations of <i>Dactylis glomerata</i>.

<p>Geographical locations of analyzed populations of <i>Dactylis glomerata</i>.</p

Principle coordinate plot of 210 <i>D</i>. <i>glomerata</i> individuals.

<p>The 15 individuals of per population were represented by the same dots.</p

Cluster analysis of <i>D</i>. <i>glomerata</i>.

<p>(A) UPGMA tree of 14 populations. (B) STRUCTURE analysis of 14 populations. (C) STRUCTURE analysis of 210 individuals. (D) STRUCTURE analysis of 14 populations using outlier loci. (E) STRUCTURE analysis of 210 individuals using outlier loci. Three colors represented different potential genetic backgrounds.</p

List of Mantel test, genetic differentiation and gene flow for <i>D</i>. <i>glomerata</i> in different regions.

<p>Codes: <i>F</i>_<i>st</i>, Nei’s genetic differentiation; <i>G’</i>_<i>st</i>, Shannon differentiation coefficient; <i>N</i>_<i>m</i>, gene flow.</p

Genetic diversity of <i>D</i>. <i>glomerata</i> distributed among populations in different sampling regions.

<p>Codes: LD, linkage disequilibrium at the 5% level; <i>N</i>_<i>p</i>, Number of polymorphic loci; PPL, percentage of polymorphic loci; <i>N</i>_<i>a</i>, observed number of alleles per locus; <i>N</i>_<i>e</i>, effective number of alleles per locus; <i>H</i>_<i>j</i>, Nei’s gene diversity index; <i>H</i>_<i>o</i>, Shannon information index.</p

Pearson correlation analysis between genetic diversity and environmental factors.

<p>Codes: <i>H</i>_<i>j</i>, Nei’s genetic diversity; <i>H</i>_<i>o</i>, Shannon information index; <i>N</i>_<i>p</i>, Number of polymorphic loci; LD, linkage disequilibrium.</p

Analysis of molecular variance of <i>D</i>. <i>glomerata</i>.

<p>Analysis of molecular variance of <i>D</i>. <i>glomerata</i>.</p

A Comprehensive Analysis of the Phylogeny, Genomic Organization and Expression of Immunoglobulin Light Chain Genes in <i>Alligator sinensis</i>, an Endangered Reptile Species

<div><p>Crocodilians are evolutionarily distinct reptiles that are distantly related to lizards and are thought to be the closest relatives of birds. Compared with birds and mammals, few studies have investigated the Ig light chain of crocodilians. Here, employing an <i>Alligator sinensis</i> genomic bacterial artificial chromosome (BAC) library and available genome data, we characterized the genomic organization of the <i>Alligator sinensis</i> IgL gene loci. The <i>Alligator sinensis</i> has two IgL isotypes, λ and κ, the same as <i>Anolis carolinensis</i>. The Igλ locus contains 6 C_λ genes, each preceded by a J_λ gene, and 86 potentially functional V_λ genes upstream of (J_λ-C_λ)_n. The Igκ locus contains a single C_κ gene, 6 J_κs and 62 functional V_κs. All V_L genes are classified into a total of 31 families: 19 V_λ families and 12 V_κ families. Based on an analysis of the chromosomal location of the light chain genes among mammals, birds, lizards and frogs, the data further confirm that there are two IgL isotypes in the <i>Alligator sinensis</i>: Igλ and Igκ. By analyzing the cloned Igλ/κ cDNA, we identified a biased usage pattern of V families in the expressed V_λ and V_κ. An analysis of the junctions of the recombined VJ revealed the presence of N and P nucleotides in both expressed λ and κ sequences. Phylogenetic analysis of the V genes revealed V families shared by mammals, birds, reptiles and <i>Xenopus</i>, suggesting that these conserved V families are orthologous and have been retained during the evolution of IgL. Our data suggest that the <i>Alligator sinensis</i> IgL gene repertoire is highly diverse and complex and provide insight into immunoglobulin gene evolution in vertebrates.</p></div