Phylogeography of the genus Dasiphora (Rosaceae) in the Qinghai‐Tibetan Plateau: divergence blurred by expansion

Plateau uprisings and climatic oscillations are considered to have caused extensive allopatric divergences that account for the rich species diversity of the Qinghai‐Tibetan Plateau (QTP). However, secondary contact during range shifts in the Quaternary glacial cycles or inter‐uplift stages may have restored the gene flow between species and so counteracted these divergences, particularly in rapidly‐adapting dominant elements. We tested this hypothesis by determining the phylogeographical history of Dasiphora (Rosaceae), a genus of two species that are widely distributed on the QTP and co‐exist in numerous localities. We sequenced two chloroplast DNA fragments (rbcL, trnT‐L) for 559 individuals from 87 populations. Bayesian methods were used to identify phylogenetic relationships and to estimate divergence times. Demographic histories were inferred using neutrality tests, mismatch distribution analysis, and coalescent simulation. A total of 112 haplotypes that clustered into three major groups were identified. The formation of these groups and their subgroups was dated to between the Pliocene and the late Pleistocene. In addition, we found that some groups underwent multiple extensive expansions. Species‐specific haplotypes were identified for each species, although these haplotypes phylogenetically intermixed. These results suggest that recent plateau uplifts and climatic oscillations might have caused the deep divergences observed within this genus. However, later range expansions probably blurred these divergences and possible species boundaries. Our results shed new light on the complex evolutionary history of the QTP alpine plants. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 777–788.     

Soil fertility and its significance to crop productivity and sustainability in typical agroecosystem: a summary of long-term fertilizer experiments in China

Aims and background

Soil fertility quality index is a useful indicator that helps to improve sustainable land use management and achieve economical yield in agriculture production. The objectives of this study were to evaluate the changes of soil fertility quality between the 1980s and 2000s in different cropping systems and its significance to crop productivity and sustainability.

Methods

We collected all published data on crop yields and soil parameters from 58 long-term experiments in three typical double-cropping systems in China, including maize-wheat (M-W), rice-rice (R-R) and rice-wheat (R-W) cropping systems, and selected seven fertilizer treatments in each experiment, including inorganic fertilizer [nitrogen and phosphorus fertilizer (NP), nitrogen and potassium fertilizer (NK), phosphorus and potassium fertilizer (PK) and balanced mineral fertilizer (NPK)], combined NPK with farmyard manure (NPKM) or crop straw (NPKS), and no fertilizer application (served as control). For comparison, an integrated fertility quality index (IFQI) was used to estimate the variations in soil fertility in different cropping systems. Moreover, the mean production variability index (PVI, %) in each cropping system was calculated to evaluate the stability of crop production.

Results

Over cropping systems, the averaged relative yields of PK, NK and NP ranged from 38.0 to 97.4 %, while the mean yields can be increased by 2.4–5.1 % in NPKM, compared to NPK. The mean yields were similar between NPK and NPKS for maize and wheat crops, but the yield was increased by 4.3–10.0 % in NPKS. Among the different treatments, the highest variability of cereal productivity was obtained in NK, PK or Control, while the lowest value was mostly recorded in NPKM or NPKS in these three cropping systems. Relative to the control, the IFQIs in fertilization treatments were increased by 9.4–150.0 %, 6.2–41.5 % and 1.3–17.5 % in M-W, R-W and R-R systems, respectively (except for PK treatment in R-R system). However, changes of IFQI in topsoil differed among fertilizer treatments, and greater increases existed in the treatments receiving organic residues (NPKM and NPKS).

Conclusions

The increase in crop yield is exponentially correlated with the increased IFQI over treatments in three cropping systems. Over the treatments and systems, production variability among years is shown to be negatively, linearly related to IFQI (P?<?0.001). Therefore, the high grain yield and low production variability can be simultaneously achieved by increasing soil fertility in all three cropping systems.     

原子力显微镜技术检测几种骨组织细胞力学性能

为了探究几种骨组织细胞系的力学性能及其与细胞功能的关系,该文采用原子力显微镜压陷法分别检测了前成骨细胞系（2T3和MC3T3-E1）、前骨细胞系（MLO-A5）和骨样细胞系（MLO-Y4）的杨氏模量,利用激光共聚焦显微镜观察了这几种细胞微丝和微管的排布。结果显示,2T3、MC3T3-E1、MLO-A5和MLO-Y4细胞的杨氏模量分别为（7000±2015）Pa、（6600±2024）Pa、（4700±644）Pa和（4500±1622）Pa,与原代骨组织细胞的杨氏模量及变化趋势保持一致,但两种前成骨细胞的杨氏模量要显著高于前骨细胞和骨细胞。细胞荧光染色结果表日月＇前成骨细胞细胞核周围的微丝和微管分布密度要高于前骨细胞和骨细胞,而前骨细胞MLO-A5,尤其是骨细胞MLO-Y4的骨架主要集中于细胞突触和边缘,这可能是导致几种细胞力学性能差异的原因。该研究从生物力学的角度为进一步深入理解骨组织细胞结构与功能的关系提供了实验依据。     

MiR-320a down-regulation mediates bladder carcinoma invasion by targeting ITGB3

To investigate whether the miR-320a could regulate bladder cancer cells invasion by down-regulation of ITGB3. Real-time quantitative PCR was applied to evaluate the expression level of miRNA-320a in bladder transitional cell carcinomas (TCC) and normal bladder transitional cell (NBTC) samples. The invasion ability of miR-320a in TCC T24 cells was analyzed by Transwell assay after pre-miR-320a or anti-miR-125b transfection. For the invasion mechanism analysis of miR-320a on T24 cells, TargetScan, PicTar and miRBase were used to predict the possible target gene of miR-320a. Luciferase activities assay and western blot were used to reveal the predicted target gene of miR-320a were direct and specific. RNA interference technology was used to confirm the invasion inhibition of miR-320a was directly induced by ITGB3. Our study showed that miR-320a was down-regulated in human TCC specimens compared to that in NBTC specimens. Over-expression of miR-320a in T24 cells inhibited TCC invasion and this inhibitory effect on T24 cells could be restore by miR-320a knocked down. Mechanism analysis revealed that ITGB3 was a direct and specific target of miR-320a. The advanced effect of anti-miR-320a on TCC cell invasion was mediated by expression silence of ITGB3. In summary, aberrantly expressed miR-320a contribute to T24 cells invasion partly through directly down-regulating ITGB3 protein expression in TCC and this miRNA signature offers a novel potential therapeutic strategy for TCC.     

Prenatal diagnosis of pure partial monosomy 18p associated with holoprosencephaly and congenital heart defects

We applied CMA to detect chromosomal variations during a prenatal diagnosis and detected a 4.5 Mb pure microdeletion at 18p11.3 that was not detected by conventional karyotyping. Fluorescent in situ hybridization (FISH) analysis was performed to confirm the deletion. Accurate breakpoints of the deletion in this patient were used to build correlations between monosomy 18p and the concomitant phenotypes, particularly holoprosencephaly (HPE), which is rarely reported in monosomy 18p11.3.     

Interaction of diet and the masou salmon Δ5-desaturase transgene on Δ6-desaturase and stearoyl-CoA desaturase gene expression and N-3 fatty acid level in common carp (Cyprinus carpio)

The masou salmon Δ5-desaturase-like gene (D5D) driven by the common carp β-actin promoter was transferred into common carp (Cyprinus carpio) that were fed two diets. For P₁ transgenic fish fed a commercial diet, Δ6-desaturase-like gene (D6D) and stearoyl-CoA desaturase (SCD) mRNA levels in muscle were up-regulated (P < 0.05) 12.7- and 17.9-fold, respectively, and the D6D mRNA level in the gonad of transgenic fish was up-regulated 6.9-fold (P < 0.05) compared to that of non-transgenic fish. In contrast, D6D and SCD mRNA levels in transgenic fish were dramatically down-regulated (P < 0.05), 50.2- and 16.7-fold in brain, and 5.4- and 2.4-fold in liver, respectively, in comparison with those of non-transgenic fish. When fed a specially formulated diet, D6D and SCD mRNA levels in muscle of transgenic fish were up-regulated (P < 0.05) 41.5- and 8.9-fold, respectively, and in liver 6.0- and 3.3-fold, respectively, compared to those of non-transgenic fish. In contrast, D6D and SCD mRNA levels in the gonad of transgenic fish were down-regulated (P < 0.05) 5.5- and 12.4-fold, respectively, and D6D and SCD mRNA levels in the brain were down-regulated 14.9- and 1.4-fold (P < 0.05), respectively, compared to those of non-transgenic fish. The transgenic common carp fed the commercial diet had 1.07-fold EPA, 1.12-fold DPA, 1.07-fold DHA, and 1.07-fold higher observed total omega-3 fatty acid levels than non-transgenic common carp. Although these differences were not statistically different (P > 0.05), there were significantly (P < 0.10) higher omega-3 fatty acid levels when considering the differences for all of the individual omega-3 fatty acids. The genotype × diet interactions observed indicated that the potential of desaturase transgenesis cannot be realized without using a well-designed diet with the needed amount of substrates.     

Comparison of the Efficacy of Cord Blood Mononuclear Cells (MNCs) and CD34+ Cells for the Treatment of Neonatal Mice with Cerebral Palsy

To compare the efficacy of cord blood mononuclear cells (MNCs) and CD34+ cells for the treatment of neonatal mice models with cerebral palsy (CP). CP model in neonatal mice was established by the ligation of carotid artery. Mice were randomly designated into MNCs group, CD34+ group, model group and control group (30 mice per group). MNCs and CD34+ cells were isolated from human umbilical cord blood. MNCs were transplanted into mice in the MNCs group and CD34+ cells into mice in the CD34+ group through the jugular vein, respectively. The body weight, histopathology, apoptosis-related gene expression, learning and memory, and motor function of mice in the four groups were compared. Compared with control group, the body weight of mice in model group was significantly lower (P < 0.05). In addition, the right hemisphere was significantly liquefied and voids were found in model mice, in which degeneration and necrosis were found by HE staining. Real-time quantitative fluorescent PCR showed elevated levels of apoptosis-related gene expression and learning and memory function, and motor function were significantly decreased (P < 0.05) in model mice. In the MNCs group and CD34+ group, the weight of mice was significantly increased compared with the model group (P < 0.05). Moreover, neither liquefaction and voids in the hemispheres of mice were found in these two groups, nor degeneration and necrosis of cell. Meanwhile, levels of apoptosis-related gene expression were significantly lower than that of the model group (P < 0.05). Compared with the MNCs group, the expression of apoptotic gene TNF-α and CD40 was significantly lower (P < 0.05). Learning and memory function, and motor function of mice in the MNCs group and CD34+ group were significantly improved than the model group (P < 0.05), and the CD34+ group produced greater improvement than the MNCs group (P < 0.05). MNCs and CD34+ cells can reduce the degree of injury in the neonatal mice with CP. In addition, treatment with MNCs and CD34+ cells suppressed apoptotic gene expression and restored memory and motor function. The efficacy of CD34+ cells after separation and purification was more significant for the treatment of mice with CP.