Osteoblast differentiation of rabbit adipose-derived stem cells by polyethylenimine-mediated BMP-2 gene transfection in vitro.

The aim of this study was to examine the efficiency of polyethylenimine-mediated transfection of the human bone morphogenetic protein-2 (BMP-2) gene into rabbit adipose-derived stem cells (ADSCs), and its effect on osteoblast differentiation. Adipose tissue was isolated from the necks of adult Japanese white rabbits and cultured in vitro to obtain ADSCs. Gene delivery of BMP-2 was mediated by polyethylenimine and stable transformants were selected by G-418. The expression of BMP-2 mRNA was confirmed by reverse transcription-polymerase chain reaction, and of the BMP-2 protein by ELISA. Osteocalcin and collagen type I were detected by western blot and by an alkaline phosphatase kit. Alizarin red S stain was also utilized to examine osteogenesis. The non-transfected group was considered as a control. In this study, we successfully derived ADSCs from rabbit adipose tissue. Through passages 3-6, the expression of CD29 and CD44 gradually increased, whereas the expression of CD34 and CD45 gradually decreased. Both mRNA and protein expression of BMP-2 were confirmed following polyethylenimine-mediated BMP-2 gene delivery. In addition, the expression of alkaline phosphatase, osteocalcin, and collagen type I was found to be upregulated and alizarin red S staining was positive in transfected ADSCs, indicating BMP-2-induced osteogenesis. Therefore, this study determined that polyethylenimine was able to mediate BMP-2 gene delivery and induce osteogenic differentiation of ADSCs.

Development of EST-SSR markers in the relict tree Davidia involucrata (Davidiaceae) using transcriptome sequencing.

Davidia involucrata, reputed to be a "living fossil" in the plant kingdom, is a relict tree endemic to China. Extant natural populations are diminishing due to anthropogenic disturbance. In order to understand its ability to survive in a range of climatic conditions and to design conservation strategies for this endangered species, we developed genic simple sequence repeats (SSRs) from mRNA transcripts. In total, 142,950 contigs were assembled. Of these, 30,411 genic SSR loci were discovered and 12,208 primer pairs were designed. Dinucleotides were the most common (77.31%) followed by trinucleotides (16.44%). Thirteen randomly selected primers were synthesized and validated using 24 individuals of D. involucrata. The markers displayed high polymorphism with the number of alleles per locus ranging from 3 to 12 and the observed and expected heterozygosities ranging from 0.083 to 1.0 and 0.102 to 0.69, respectively. This large expressed sequence tag dataset and the novel SSR markers will be key tools in comparative studies that may reveal the adaptive evolution, population structure, and resolve the genetic diversity in this endangered species.

Development of expressed sequence tag-based microsatellite markers for the critically endangered Isoëtes sinensis (Isoetaceae) based on transcriptome analysis.

Isoëtes sinensis is a critically endangered quillwort. To facilitate studies on the conservation genetics of this species, we developed expressed sequence tag-simple sequence repeat (EST-SSR) markers. A total of 50,063 unigenes were predicted by transcriptome sequencing, 5294 (10.6%) of which significantly matched 3011 Gene Ontology annotations and 2363 were assigned to Kyoto Encyclopedia of Genes and Genomes metabolic pathways. Most of these (2297) were involved in metabolism. A total of 1982 SSR motifs were identified, with trinucleotides being the dominant repeat motif, and 1438 (72.6%) SSR primers were designed. Eighteen randomly selected primer pairs were used to genotype 24 I. sinensis accessions, which confirmed the suitability of these novel markers for molecular studies of I. sinensis. The heterozygosity index value ranged between 0.0799 and 0.9106, while the Shannon-Wiener diversity index value ranged between 0.1732 and 2.5589. The EST-SSRs reported in this study are linked to genic sequences, and are therefore ideal for investigating the evolutionary history of I. sinensis. These markers, together with the large EST dataset generated in this study, will greatly facilitate conservation genetic studies of I. sinensis.

Development of microsatellite markers in Hagenia abyssinica (Bruce) J.F. Gmel, an endangered tropical tree of eastern Africa, using next-generation sequencing.

Hagenia abyssinica (Bruce) J.F. Gmel is an endangered tree species endemic to the high mountains of tropical Africa. We used Illumina paired-end technology to sequence its nuclear genome, aiming at creating the first genomic data library and developing the first set of genomic microsatellites. Seventeen microsatellite markers were validated in 24 individuals. The average number of alleles per locus was 7.6, while the observed and expected heterozygosities ranged from 0.000 to 0.958 and from 0.354 to 0.883, respectively. These polymorphic markers will be used as tools for further molecular studies to facilitate formulation of appropriate conservation strategies for this species.

Low vaspin levels are related to endothelial dysfunction in patients with ankylosing spondylitis.

Vaspin is a novel adipocytokine associated with glucose tolerance and chronic inflammation. Some studies reveal that vaspin may be involved in cardiovascular diseases. Our objective was to investigate the relationship between serum vaspin levels and endothelial function in patients with ankylosing spondylitis. One hundred and twenty patients with newly diagnosed ankylosing spondylitis and 100 healthy subjects were studied. Serum vaspin levels were measured with enzyme-linked immunosorbent assay. High resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (flow-mediated dilation, FMD) and after sublingual glyceryltrinitrate. Serum vaspin level in patients was 1.92±1.03 ng/mL, which was significantly lower than that in healthy subjects (2.88±0.81 ng/mL). By dividing the distribution of serum vaspin levels into quartiles, FMD levels increased gradually with the increase of serum vaspin levels in patients (P<0.01). Univariate analysis showed a correlation between vaspin and FMD (r=0.73, P=0.003), low-density lipoprotein cholesterol (r=-0.45, P=0.033), high-density lipoprotein cholesterol (r=0.63, P=0.025), fasting blood glucose (r=-0.79, P=0.006), triglycerides (TG) (r=-0.68, P=0.036), systolic blood pressure (r=-0.35, P=0.021), C-reactive protein (r=-0.67, P=0.011), homeostatic model assessment of insulin resistance (HOMA-IR) (r=-0.77, P=0.023) and erythrocyte sedimentation rate (r=-0.88, P=0.039) in patients. Multivariate analysis indicated that serum vaspin levels were independently associated with FMD, HOMA-IR and TG in patients. Our study found that serum vaspin levels were decreased in patients with ankylosing spondylitis and were associated with FMD levels. Vaspin may serve as an independent marker for detecting early stage atherosclerosis in patients with ankylosing spondylitis.

Development and characterization of microsatellite loci in Brasenia schreberi (Cabombaceae) based on the next-generation sequencing.

To understand genetic variability of the endangered aquatic herb Brasenia schreberi (Cabombaceae), we describe 31 microsatellite markers obtained using next-generation sequencing. A total of 24 individuals from the population of Jackson Lake, USA, were genotyped for each marker. Twenty-eight markers were polymorphic. The number of alleles per locus ranged from 1 to 9; the observed and expected heterozygosities ranged from 0 to 1 and from 0 to 0.751, respectively. These markers should be useful tools for genetic variation and conservation studies of B. schreberi.

Development of microsatellite markers in the tetraploid fern Ceratopteris thalictroides (Parkeriaceae) using RAD tag sequencing.

To understand the genetic variability of the tetraploid fern Ceratopteris thalictroides (Parkeriaceae), we described 30 polymorphic microsatellite markers obtained using the restriction site-associated DNA (RAD) tag sequencing technique. A total of 26 individuals were genotyped for each marker. The number of alleles per locus ranged from 4 to 10, and the expected heterozygosity and the Shannon-Wiener index ranged from 0.264 to 0.852 and 0.676 to 2.032, respectively. Because these 30 microsatellite markers exhibit high degrees of genetic variation, they will be useful tools for studying the adaptive genetic variation and sustainable conservation of C. thalictroides.

Low vaspin levels are related to endothelial dysfunction in patients with ankylosing spondylitis

Vaspin is a novel adipocytokine associated with glucose tolerance and chronic inflammation. Some studies reveal that vaspin may be involved in cardiovascular diseases. Our objective was to investigate the relationship between serum vaspin levels and endothelial function in patients with ankylosing spondylitis. One hundred and twenty patients with newly diagnosed ankylosing spondylitis and 100 healthy subjects were studied. Serum vaspin levels were measured with enzyme-linked immunosorbent assay. High resolution ultrasound was used to measure brachial artery diameter at rest, after reactive hyperemia (flow-mediated dilation, FMD) and after sublingual glyceryltrinitrate. Serum vaspin level in patients was 1.92±1.03 ng/mL, which was significantly lower than that in healthy subjects (2.88±0.81 ng/mL). By dividing the distribution of serum vaspin levels into quartiles, FMD levels increased gradually with the increase of serum vaspin levels in patients (P<0.01). Univariate analysis showed a correlation between vaspin and FMD (r=0.73, P=0.003), low-density lipoprotein cholesterol (r=-0.45, P=0.033), high-density lipoprotein cholesterol (r=0.63, P=0.025), fasting blood glucose (r=-0.79, P=0.006), triglycerides (TG) (r=-0.68, P=0.036), systolic blood pressure (r=-0.35, P=0.021), C-reactive protein (r=-0.67, P=0.011), homeostatic model assessment of insulin resistance (HOMA-IR) (r=-0.77, P=0.023) and erythrocyte sedimentation rate (r=-0.88, P=0.039) in patients. Multivariate analysis indicated that serum vaspin levels were independently associated with FMD, HOMA-IR and TG in patients. Our study found that serum vaspin levels were decreased in patients with ankylosing spondylitis and were associated with FMD levels. Vaspin may serve as an independent marker for detecting early stage atherosclerosis in patients with ankylosing spondylitis.

Fine-scale spatial genetic structure of an endangered marsh herb, Caldesia grandis (Alismataceae).

The endangered marsh herb, Caldesia grandis, is native to China. We investigated the spatial structure of the genetic variation of three populations of C. grandis using RAPD markers and spatial autocorrelation analysis, based on the method of equal distance interval. A total of 157 individuals were sampled from four patches collected from the region of Hunan and Yunnan Provinces, China. Among the polymorphic bands generated by seven selective primers, polymorphic bands with frequencies ranging from 20 to 80% were used to calculate Moran's I spatial autocorrelation coefficient for each patch. We found significant spatial structure of genetic variation in the three patches in Bei Hai (BH) (patches BH-1 and BH-2) and Guai Hu (GH) (patch GH-1) populations of C. grandis (with significant positive autocorrelation within the short distance class). In contrast, the genetic variation in the Lang Pan Hu (LPH) population (patch LPH-1) was found to be randomly distributed. The different spatial distribution patterns may be attributed to environment differences. These results have implications for the conservation and management of this species, especially for sampling strategies for ex situ conservation.

Isolation and characterization of polymorphic microsatellite loci from the invasive plant Solidago canadensis (Asteraceae).

Solidago canadensis, a clonal herb originally from North America (common name: Canada goldenrod), is an invasive species in many countries. We developed microsatellite primers for this species. Eleven polymorphic loci were generated and primers were designed. Polymorphism of these 11 loci was assessed in 35 plants from two populations (Wuhan and Shanghai) in China. The number of alleles per locus ranged from 3 to 14. The observed and expected heterozygosities varied from 0.0732 to 0.7391 and from 0.1177 to 0.8687, respectively. These microsatellite markers will be useful tools for studies of population genetics in the native and invasive range of this species.