Assessing the potential of candidate DNA barcodes for identifying non-flowering seed plants

In plants, matK and rbcL have been selected as core barcodes by the Consortium for the Barcode of Life (CBOL) Plant Working Group (PWG), and ITS/ITS2 and psbA-trnH were suggested as supplementary loci. Yet, research on DNA barcoding of non-flowering seed plants has been less extensive, and the evaluation of DNA barcodes in this division has been limited thus far. Here, we evaluated seven markers (psbA-trnH, matK, rbcL, rpoB, rpoC1, ITS and ITS2) from non-flowering seed plants. The usefulness of each region was assessed using four criteria: the success rate of PCR amplification, the differential intra- and inter-specific divergences, the DNA barcoding gap and the ability to discriminate species. Among the seven loci tested, ITS2 produced the best results in the barcoding of non-flowering seed plants. In addition, we compared the abilities of the five most-recommended markers (psbA-trnH, matK, rbcL, ITS and ITS2) to identify additional species using a large database of gymnosperms from GenBank. ITS2 remained effective for species identification in a wide range of non-flowering seed plants: for the 1531 samples from 608 species of 80 diverse genera, ITS2 correctly authenticated 66% of them at the species level. In conclusion, the ITS2 region can serve as a useful barcode to discriminate non-flowering seed plants, and this study will contribute valuable information for the barcoding of plant species.

Polysaccharide-K (PSK) in cancer--old story, new possibilities?

Polysaccharide-K (PSK, Krestin) is one of the most commonly used medicinal mushroom extracts with a long history as an additive in cancer therapy in Asia, especially in Japan. PSK has a documented anti-tumor activity both in vitro and in vitro, in various types of cancers, including colorectal, gastric, breast, liver, pancreatic, and lung cancer. Despite PSK having been studied for about 40 years as an immune modulator and biological response modifier, the mechanisms of action by PSK have not yet been clearly and completely elucidated. This review aims to provide an up-to-date account for the effects of PSK in cancer with the hope of thereby providing an increased understanding of the molecular mechanisms of PSK and also its potential as an additive in modern cancer therapy.

The onion skin-like organization of the septum arises from multiple embryonic origins to form multiple adult neuronal fates

In the past several decades, tremendous progress has been achieved through developmental studies of the central nervous system structures such as the cerebral cortex. The septum, which receives reciprocal connections from a variety of brain structures, contains diverse projection neurons but few interneurons. However, the mechanisms underlying its development remain poorly understood. Here we show that the septum is organized into an onion skin-like structure composed of five groups of neurons. These neurons are parvalbumin, choline acetyltransferase, neuronal nitric oxide synthase, calretinin and calbindin immunoreactive. Using the BrdU birth-dating method, we found that these five groups of neurons in the septum are grossly generated following an outside-in pattern. Interestingly, the distinct molecular identities of these neuronal subtypes correspond to their heterogeneous subpallial origins. Using three specific transgenic mouse lines and focal in utero electroporation of Cre-reporter plasmid, we showed that septal neurons originate from not only local progenitor regions but also neighboring progenitor regions including the medial ganglionic eminence and preoptic area. Thus, the neuronal diversity of the septum is achieved through both temporal and spatial control. Our results also suggest that multiple neuronal subtypes arrive to the septum through both radial and tangential migration. Based on these findings, we proposed a novel developmental model involving multiple spatial-temporal origins of septal neurons. This study presents new perspectives for comprehensively exploring septal functions in brain circuits.

Zoledronate and pamidronate depress neutrophil functions and survival in mice

BACKGROUND AND PURPOSE

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been identified as a severe complication of patients previously treated with i.v. bisphosphonates. It has been noted that necrotic bone from BRONJ sites display signs of bacterial infection suggesting that an immune defect may play a role in the pathophysiology of BRONJ. Here, we have examined the effect of two potent bisphosphonates, zoledronate and pamidronate, on neutrophil function, differentiation and survival.

EXPERIMENTAL APPROACH

The effect of bisphosphonates on chemotaxis, NADPH oxidase activity and neutrophil survival were assessed in vitro using bone marrow-derived primary neutrophils or in vitro differentiated haematopoetic progenitors from mice. The same parameters and the number of circulating neutrophils were quantified in neutrophils isolated from mice treated in vivo with zoledronate. In vivo recruitment of neutrophils was assessed by sodium periodate-induced peritonitis.

KEY RESULTS

Zoledronate and pamidronate inhibited in vitro neutrophil chemotaxis and NADPH oxidase activity in a dose-dependent manner. In vivo recruitment of neutrophils was also suppressed. Zoledronate did not affect in vitro differentiation of neutrophils but shortened their life span in a granulocyte-colony stimulating factor-dependent manner. fMLP-induced activation of RhoA activity was decreased by zoledronate treatment.

CONCLUSIONS AND IMPLICATIONS

Our results show that bisphosphonate exposure leads to impaired neutrophil chemotaxis, neutrophil NADPH oxidase activity and reduced circulating neutrophil counts. This work suggests that bisphosphonates have the potential to depress the innate immune system for a prolonged time, possibly contributing to the pathogenesis of BRONJ.

Neurotrophic effect of bone marrow mesenchymal stem cells for erectile dysfunction in diabetic rats

It has been demonstrated that intracavernous injection of bone marrow-derived mesenchymal stem cells (BM-MSCs) had beneficial effects on improving erectile function in type-1 diabetic rats. This study was designed to investigate the neurotrophic effect of BM-MSCs for type-1 diabetic rats. Streptozocin-induced type-1 diabetic rats were randomly divided into three groups: diabetic group, BM-MSCs-treated group and BM-MSCs-conditioned medium-treated group. At the 3d, 1 and 2w time points after BM-MSCs injection, three randomly selected rats in MSCs group were sacrificed and penile samples were harvested to detect BM-MSCs in penile tissue. Four weeks after intracavernous injection of BM-MSCs or BM-MSCs-conditioned medium, intracavernous pressure (ICP) was assessed to evaluate the erectile function. Immunohistochemistry was used to track labelled BM-MSCs in penile tissue and to detect neuronal nitric oxide synthase (nNOS) and neurofilament (NF) positive fibres in penile dorsal nerve. Enzyme lined immunosorbent assay (ELISA) was used to measure the concentrations of vascular endothelial growth factor (VEGF), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in BM-MSCs-conditioned medium. BM- MSCs secreted detectable levels of VEGF, BDNF and NGF. Intracavernous injection of BM-MSCs improved erectile function in diabetic rats. The functional improvement was accompanied by promoted nNOS and NF positive nerve fibres within penile dorsal nerve in type-1 diabetic rats. Histological data revealed a time-dependent decrease in the number of BM-MSCs in the corpus cavernosum following injection. Furthermore, the beneficial effect of BM-MSCs was partially repeated by BM-MSCs-conditioned medium. Intracavernous injection of BM-MSCs is effective in improving nerve regeneration in diabetic rats. Paracrine effects of BM-MSCs are probably involved in the improvement.

Selective FLT3 inhibition of FLT3-ITD+ acute myeloid leukaemia resulting in secondary D835Y mutation: a model for emerging clinical resistance patterns

Acquired resistance to selective FLT3 inhibitors, is an emerging clinical problem in the treatment of FLT3-ITD⁺ acute myeloid leukaemia (AML). The paucity of valid pre-clinical models has limited investigations to determine the mechanism of acquired therapeutic resistance, thereby limiting the development of effective treatments. We generated selective FLT3 inhibitor-resistant cells by treating the FLT3-ITD⁺ human AML cell line MOLM-13 in vitro with the FLT3-selective inhibitor MLN518, and validated the resistant phenotype in vivo and in vitro. The resistant cells, MOLM-13-RES, harboured a new D835Y tyrosine kinase domain (TKD) mutation on the FLT3-ITD⁺ allele. Acquired TKD mutations, including D835Y, have recently been identified in FLT3-ITD⁺ patients relapsing after treatment with the novel FLT3 inhibitor, AC220. Consistent with this clinical pattern of resistance, MOLM-13- RES cells displayed high relative resistance to AC220 and Sorafenib. Furthermore, treatment of MOLM-13-RES cells with AC220 lead to loss of the FLT3 wild type allele and duplication of the FLT3-ITD-D835Y allele. Our FLT3-Aurora kinase inhibitor, CCT137690, successfully inhibited growth of FLT3-ITD-D835Y cells in vitro and in vivo, suggesting that dual FLT3-Aurora inhibition may overcome selective FLT3 inhibitor resistance, in part due to inhibition of Aurora kinase, and may benefit patients with FLT3-mutated AML.

Derivation of male germ cells from induced pluripotent stem cells in vitro and in reconstituted seminiferous tubules

OBJECTIVES

Previous studies have demonstrated that mouse- and human-induced pluripotent stem (iPS) cells can differentiate into primordial germ cells in vitro. However, up to now it is not known whether iPS cells would be able to differentiate into male germ cells in vivo. The aim of this study was to explore differentiation potential of iPS cells to male germ cells in vitro and in vivo.

MATERIALS AND METHODS

In this study, approaches using in vitro retinoic acid induction and in vivo ectopic transplantation were combined to induce iPS cells to become male germ cells.

RESULTS

RT-PCR showed that expression of pre-meiotic and meiotic germ cell-specific genes was enhanced in iPS cell-derived embryoid bodies (EBs) compared to mRNA transcripts of iPS cells. Immunofluorescence analysis revealed that iPS cell-derived EBs positively expressed germ-cell markers VASA, c-Kit and SCP3. Furthermore, iPS cell-derived cells dissociated from EBs were injected with testicular cells into dorsal skin of mice. Histological examination showed that iPS cell-derived cells could reconstitute seminiferous tubules, and meanwhile, iPS cell-derived germ cells could settle at basement membranes of reconstituted tubules.

CONCLUSION

Our results suggest that iPS cells are able to differentiate into male germ cells in vitro and that reconstituted seminiferous tubules may provide a functional niche for exogenous iPS cell-derived male germ cells. Derivation of male germ cells from iPS cells has potential application for treating male infertility and provides an ideal platform for elucidating molecular mechanisms of male germ-cell development.

Fluxes, variability and sources of cadmium, lead, arsenic and mercury in dry atmospheric depositions in urban, suburban and rural areas

In China's largest city, Shanghai, dry deposition fluxes of Cd, Pb, As and Hg were 137, 19354, 2897 and 9.4 μgm(-2)a(-1), respectively in an urban area, intermediate in a suburban area, and 51.7, 5311, 1703 and 7.3 μgm(-2)a(-1), respectively in a rural area. Enrichment factors were Cd>Pb>As>Hg. Seasonal variations of metals differed: Pb and As were dominated by fossil fuel combustion, Cd was related to industrial pollution, and natural source controlled Hg levels.

454 EST analysis detects genes putatively involved in ginsenoside biosynthesis in Panax ginseng

Panax ginseng C.A. Meyer is one of the most highly valued medicinal plants in the world. To analyze the transcriptome of P. ginseng and discover the genes involved in ginsenoside biosynthesis, cDNAs derived from the total RNA of 11-year-old, wood-grown P. ginseng roots were analyzed by 454 sequencing. A total of 217,529 high quality reads (expressed sequence tags, ESTs), with an average length of 409 bases, were generated from a one-quarter run to yield 31,741 unique sequences. The majority (20,198; 63.6%) of the unique sequences were annotated using BLAST similarity searches. A total of 16,810 and 16,577 unique sequences were assigned to functional classifications and biochemical pathways based on Gene Ontology analysis and the Kyoto Encyclopedia of Genes and Genomes assignment, respectively. Nine genes involved in the biosynthesis of ginsenoside skeletons and many candidate genes putatively responsible for modification of the skeletons, including 133 cytochrome P450s and 235 glycosyltransferases, were identified. From these candidates, six transcripts encoding UDP-glycosyltransferases that were most likely to be involved in ginsenoside biosynthesis were selected. These results open a new avenue by which to explore and exploit biosynthetic and biochemical properties that may lead to drug improvement. These 454 ESTs will provide the foundation for further functional genomic research into the traditional herb P. ginseng or its closely related species.