Characterization and identification of ISSR markers associated with oil content in sea buckthorn berries.

Bioactive oils extracted from sea buckthorn (Hippophae rhamnoides) berries contain highly nutritional and medicinal compounds; however, the oil contents of sea buckthorn berries are very low. Thirteen inter-simple sequence repeat (ISSR) primers were used to identify markers associated with oil content of dry pulp in 51 cultivars and lines, which clustered into three major groups based on 137 polymorphic markers. Dry pulp oil contents in 45 cultivars and lines in Group I ranged from 6.6 to 33.1%; these accessions belonged to H. rhamnoides ssp mongolica and its hybrids with H. rhamnoides ssp sinensis. Three lines (H. rhamnoides ssp mongolica) in Group II had high dry pulp oil contents (33.7 to 37.5%), whereas three lines of hybrids in Group III had low dry pulp oil contents (10.9 to 17.5%). The dry pulp oil content of H. rhamnoides ssp mongolica (27.2 ± 0.9%) was higher than that of hybrids (12.0 ± 1.2%) (P < 0.01). Four ISSR markers (881340, 8251000, 817380, and 8071100) had positive association with high dry pulp oil content (P < 0.01) using stepwise multiple regression analysis. The use of these ISSR markers is a potential strategy to select genotypes with high dry pulp oil content and suitable parental combinations for improvement of sea buckthorn berries.

A new strategy for complete identification of sea buckthorn cultivars by using random amplified polymorphic DNA markers.

DNA fingerprinting is both a popular and important technique with several advantages in plant cultivar identification. However, this technique has not been used widely and efficiently in practical plant identification because the analysis and recording of data generated from fingerprinting and genotyping are tedious and difficult. We developed a novel approach known as a cultivar identification diagram (CID) strategy that uses DNA markers to separate plant individuals in a more efficient, practical, and referable manner. A CID was manually constructed and a polymorphic marker was generated from each polymerase chain reaction for sample separation. In this study, 67 important sea buckthorn cultivars cultivated in China were successfully separated with random amplified polymorphic DNA markers using the CID analysis strategy, with only seven 11-nucleotide primers employed. The utilization of the CID of these 67 sea buckthorn cultivars was verified by identifying 2 randomly chosen groups of cultivars among the 67 cultivars. The main advantages of this identification strategy include fewer primers used and separation of all cultivars using the corresponding primers. This sea buckthorn CID was able to separate any sea buckthorn cultivars among the 67 studied, which is useful for sea buckthorn cultivar identification, cultivar-right-protection, and for the sea buckthorn nursery industry in China.

Th17/Treg imbalance in patients with liver cystic echinococcosis.

Echinococcosis is a chronic parasitic infectious disease regulated by T-cell subsets. CD4(+) CD25(+) FoxP3 (+) regulatory T (Treg) cells and Th17 cells have been described as two distinct subsets and have the opposite effect on inflammation. Th17/Treg balance controls inflammation and may play an important role in the pathogenesis of immune evasion. To assess whether this balance was broken, we detected Th17/Treg functions in different levels including cell frequencies, related cytokines secretion and key transcription factors in patients with cystic echincoccosis and healthy controls. The results demonstrated that patients with cystic echinococcosis revealed significant increase in peripheral Treg number, related cytokines (IL-10 and TGF-ß1) and transcription factor (Foxp3) levels and moderate decrease in Th17 number, related cytokines (IL-17 and IL-23) and transcription factor (RORγt) levels as compared with controls. Results indicated that Th17/Treg functional imbalance exists in patients with chronic cystic echinococcosis, suggesting a potential role for Th17/Treg imbalance in the pathogenesis of immune evasion in echinococcosis.

TLR2 and TLR4 expression in peripheral blood mononuclear cells of patients with chronic cystic echinococcosis and its relationship with IL-10.

This study aims at relating Toll-like receptors (TLR) and human systemic cytokines in patients with chronic cystic echinococcosis (CE). By real-time fluorescent quantitative reverse-transcription polymerase chain reaction, we measured the expression level of TLR2 and TLR4 mRNA in peripheral blood mononuclear cells (PBMCs), and using ELISA, we detected the cytokines IFN-γ, IL-12p70, IL-10, IL-4 and IL-17A from 34 chronic CE cases (four patients with biliary leakage; four patients with secondary location including three in lung and one in bone) and 22 healthy controls (HC). TLR2 and TLR4 mRNA expression were significantly higher in the CE group (P<0·05); levels of serum IL-10, IL-4 and IL-12p70 in patients with CE were significantly higher than those in controls (P<0·05). There were no differences in IFN-γ and IL-17A levels between the CE group and the HC group (P>0·05). In the patients with CE, positive correlations were noted between the expression of TLR2 and the serum level of IL-10, as well as between the expression of TLR4 and the serum level of IL-10. Our findings supported the hypothesis that during chronic CE infection, altered TLR expression might be involved in the cytokine modulation, which allowed the parasite to escape host immunosurveillance and promoted chronic infection.

Nanomechanical behaviors of microcantilever-based single-stranded DNA chips induced by counterion osmotic effects.

Experiments show that deflections of microcantilever-DNA chip can be induced by many factors, such as grafting density, hybridization efficiency, concentration, length and sequence of DNA molecules, buffer salt concentration, time, and temperature variation. However, there are few theoretical works on microcantilever-DNA chips. The present paper is aimed to study the influence of counterion effects of single-stranded DNA (ssDNA) polyelectrolyte solution on the nanomechanical behaviors of microcantilever-based ssDNA chips during packing process. First, the effect of osmotic pressure induced by ingress of counterions into DNA brush structures is studied with Hagan's model for a cylindrical polyelectrolyte brush system on the basis of Poisson-Boltzmann distribution hypothesis. Second, Zhang's two-variable method for a laminated cantilever is used to formulate a four-layer energy model for ssDNA chips with weak interactions. Third, the influence of grafting density, ssDNA chain length, and salt concentration on packing deflection is investigated using the principle of minimum energy. The predictive tendency is qualitatively similar to those observed in some related ssDNA chip experiments. The difference between the four-layer model and the simplified two-layer model for ssDNA chips is also discussed.