Hematopoietic stem cells are widely recognized as attractconditions employed, Ͼ75% of the target cells retained the ive targets for gene therapy but current protocols to trans-CD34 + Lin − primitive phenotype after 4-5 days in culture; of duce these cells using recombinant retroviral vectors are those у25% expressed a high level of GFP detectable by inefficient. To evaluate optimization of retroviral transducboth flow cytometric analysis and fluorescence tion of hematopoietic stem cells and stability of gene microscopy. When transduced cells were cultured in clonexpression in their progeny, the green fluorescent protein ogenic progenitor assays, GFP fluorescence was readily (GFP) was explored as a reporter. We first improved sensidetected in situ, indicating that GFP expression was stable tivity of detection Ͼ100-fold over that achieved previously and not detrimental to the differentiative potential of the by using a novel retroviral vector (termed MGIN) expresstransduced CD34 + Lin − cells. We conclude that GFP is ing a high level of an enhanced GFP gene. Primitive effective as a vital marker to quantify retrovirus-mediated human hematopoietic cells bearing the CD34 surface gene transfer into human hematopoietic and perhaps antigen and lacking lineage differentiation markers other types of stem/progenitor cells, and monitor (CD34 + Lin − ) were transduced with the MGIN vector using gene expression during their subsequent cell lineage a clinically applicable supernatant procedure. Under the determinations.Keywords: gene therapy; gene transfer; gene expression; retroviral vectors; GFP; hematopoietic stem cells HSPC, the second problem associated with retroviral vecIntroduction tor-based gene therapy is low levels of sustained gene Hematopoietic stem and progenitor cells (HSPC) provide expression. Retroviral vectors derived from Moloney an attractive target for gene therapy because they have murine leukemia virus (MoMLV) are the most commonly the potential to continue producing progeny cells conused retroviral vectors in clinical trials. In a standard containing a therapeutic gene indefinitely. Hematological figuration, the gene of interest is placed under the trandiseases potentially benefiting from HSPC-based gene scriptional control of the viral long terminal repeat (LTR) therapy approaches include hereditary hemoglobinosince gene expression driven by LTR is generally higher pathies, immune deficiencies and disorders of phagocytic than by an internal promoter. 9,10 However, it has been cells, as well as other diseases such as acquired immunoreported that MLV LTR-mediated gene expression is fredeficiency syndrome and cancer. 1 Retroviral vectors, quently down-regulated during differentiation of which are being used in the majority of current clinical HSPC. 11,12 Because the LTR of the murine stem cell virus trials, are a primary choice as the vehicle for gene deliv-(MSCV) retroviral vector is permissive for expression in ery since they are capable of integrating into cellular murine HSPC, 8,13 we were interested...

Morels (Morchella, Ascomycota), which are some of the most highly prized edible and medicinal mushrooms, are of great economic and scientific value. Morel cultivation has been a research focus worldwide for more than 100 years, and the outdoor cultivation of morels has succeeded and expanded to a large scale in China in recent years. In this study, we review the progress in recent research regarding the life cycle and reproductive systems in the genus Morchella and the current state of outdoor cultivation. Sclerotia formation and conidia production are two important phases during the life cycle. The morel species cultivated commercially in America is M. rufobrunnea based on molecular phylogenetic analysis. The species currently cultivated in China are black morels, including M. importuna, M. sextalata and M. eximia. The field cultivation of morels expanded in the majority of the provinces in China with a yield of fresh morels of 0-7620 kg per ha. The key techniques include spawn production, land preparation and spawning, the addition of exogenous nutrition, fruiting management and harvesting. The application of exogenous nutrition is the most important breakthrough in the field of morel cultivation, but the mechanism remains unclear. It was estimated that the total amount of field cultivated fresh morels was ∼500 t in 2015-2016. We also discuss the potential issues remaining in the current literature and suggest directions for future studies.

& Key message Direct, non-invasive X-ray microtomography and optical technique observations applied in stems and leaves of intact seedlings revealed that laurel is highly resistant to drought-induced xylem embolism. Contrary to what has been brought forward, daily cycles of embolism formation and refilling are unlikely to occur in this species and to explain how it copes with drought. & Context There has been considerable controversy regarding xylem embolism resistance for long-vesselled angiosperm species and particularly for the model species for refilling (Laurus nobilis L.). & Aims The purpose of this study was to resolve the hydraulic properties of this species by documenting vulnerability curves of different organs in intact plants. & Methods Here, we applied a direct, non-invasive method to visualize xylem embolism in stems and leaves of intact laurel seedlings up to 2-m tall using X-ray microtomography (microCT) observations and the optical vulnerability technique. These approaches were coupled with complementary centrifugation measurements performed on 1-m long branches sampled from adult trees and compared with additional microCT analyses carried out on 80-cm cut branches. & Results Direct observations of embolism spread during desiccation of intact laurels revealed that 50% loss of xylem conductivity (Ψ 50) was reached at − 7.9 ± 0.5 and − 8.4 ± 0.3 MPa in stems and leaves, respectively, while the minimum xylem water potentials measured in the field were − 4.2 MPa during a moderate drought season. Those findings reveal that embolism formation is not routine in Laurus nobilis contrary to what has been previously reported. These Ψ 50 values were close to those based on the flow-centrifuge technique (− 9.2 ± 0.2 MPa), but at odds with microCT observations of cut branches (− 4.0 ± 0.5 MPa).

MnO2 with oxygen vacancies nanoarray on Ti mesh (MnOx/TM) is active for N2-to-NH3 conversion, achieving a large NH3 yield of 1.63 × 10−10 mol cm−2 s−1 and a high Faradaic efficiency of 11.40% in 0.1 M Na2SO4.

The recent discovery of induced pluripotent stem cell (iPSC) technology provides an invaluable tool for creating in vitro representations of human genetic conditions. This is particularly relevant for those diseases that lack adequate animal models or where the species comparison is difficult, e.g. imprinting diseases such as the neurogenetic disorder PraderWilli syndrome (PWS). However, recent reports have unveiled transcriptional and functional differences between iPSCs and embryonic stem cells that in cases are attributable to imprinting errors. This has suggested that human iPSCs may not be useful to model genetic imprinting diseases. Here, we describe the generation of iPSCs from a patient with PWS bearing a partial translocation of the paternally expressed chromosome 15q11-q13 region to chromosome 4. The resulting iPSCs match all standard criteria of bona fide reprogramming and could be readily differentiated into tissues derived from the three germ layers, including neurons. Moreover, these iPSCs retain a high level of DNA methylation in the imprinting center of the maternal allele and show concomitant reduced expression of the disease-associated small nucleolar RNA HBII-85/SNORD116. These results indicate that iPSCs may be a useful tool to study PWS and perhaps other genetic imprinting diseases as well.