[Clinical and laboratory characteristics in patients with myeloid neoplasms complicated with clonal T large granular lymphocyte proliferation].

Objective: To analyze the clinical manifestations and laboratory features in patients with myeloid neoplasms complicated with clonal T large granular lymphocyte (T-LGL) proliferation. Methods: The clinical data of 5 patients with myeloid neoplasms complicated with clonal T-LGL proliferation from November 2017 to November 2018 in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College were analyzed retrospectively. Results: The median age was 60 years old. All patients had a history of abnormal peripheral blood cell counts for over 6 months. The absolute lymphocyte count in peripheral blood was less than 1.0×10(9)/L. In addition to the typical T-LGL phenotype, the immunophenotype was heterogenous including CD4(+)CD8(-) in 2 patients, the other 3 CD4(-)CD8(+). Four patients were αß type T cells, the other one was γδ type. STAT3 mutation was detected in 1 patient by next-generation sequencing, the other 4 cases were negative. Conclusions: Clonal T-LGL proliferation with myeloid neoplasm develops in an indolent manner, mainly in elderly patients. Hemocytopenia is the most common manifestation. The diagnosis of T-LGL proliferation does not have specific criteria, that it should be differentiated from other T cell proliferative disorders, such as T-cell clones of undetermined significance. STAT3 or STAT5b mutation may help distinguish.

Structural responses of metallic glasses under neutron irradiation.

Seeking nuclear materials that possess a high resistance to particle irradiation damage is a long-standing issue. Permanent defects, induced by irradiation, are primary structural changes, the accumulation of which will lead to structural damage and performance degradation in crystalline materials served in nuclear plants. In this work, structural responses of neutron irradiation in metallic glasses (MGs) have been investigated by making a series of experimental measurements, coupled with simulations in ZrCu amorphous alloys. It is found that, compared with crystalline alloys, MGs have some specific structural responses to neutron irradiation. Although neutron irradiation can induce transient vacancy-like defects in MGs, they are fully annihilated after structural relaxation by rearrangement of free volumes. In addition, the rearrangement of free volumes depends strongly on constituent elements. In particular, the change in free volumes occurs around the Zr atoms, rather than the Cu centers. This implies that there is a feasible strategy for identifying glassy materials with high structural stability against neutron irradiation by tailoring the microstructures, the systems, or the compositions in alloys. This work will shed light on the development of materials with high irradiation resistance.

Structural mechanism of the enhanced glass-forming ability in multicomponent alloys with positive heat of mixing.

The issue, microalloying certain element with positive heat of mixing leading to the enhanced glass forming ability (GFA) in multicomponent alloys, has been investigated by systematic experimental measurements coupled with theoretical calculations. It is found that in the Nb-doped CuZr alloys, strong interaction between Nb and Zr atoms leads to a shortened pair distance. In addition, fraction of the icosahedral-like local structures increases with Nb addition and Nb solutes are apt to be separated with each other. These factors contribute to an increase of the atomic level efficiency to fill space and formation of the short-to-medium range orderings. As a result, the amorphous structure is stabilized and the GFA is enhanced accordingly. This work provides an in-depth understanding of microalloying-induced high GFAs in multicomponent alloys and is helpful for guiding the development of more metallic glasses with high GFAs via microalloying, despite the positive heat of mixing between the constituent elements.

[Developmental expression of Arabidopsis methyltransferase genes MET1, DRM2 and CMT3].

Cytosine methylation is an epigenetic mark found in the genome of fungi, plants, and animals. DNA methylation is catalyzed by DNA methyltransferases. The function of DNA methyltransferases was shown to be highly conversed, but biological role of these enzymes has not been clearly defined. We generated transgenic plants expressing METHYLTRANSFERASES::GUS reporter genes for three major DNA methyltransferases (MET1, DRM2 and CMT3) to gain insight into the potential physiological relevance of the distinct members of the DNA methyltransferase family in Arabidopsis thaliana, and to investigate the expression patterns in detail. We found that METHYLTRANSFERASE::GUS genes display unique tissue, cell-type, and temporal patterns of expression throughout normal development, particularly in the flower. Our findings are supported by semi-quantitative reverse-transcription PCR, as well as by analyses of microarray databases. These data suggest that DNA methyltransferase may contribute to morphogenesis at every developmental stage and in every plant organ.

Atomic-scale mechanisms of the glass-forming ability in metallic glasses.

The issue, composition dependence of glass-forming ability (GFA) in metallic glasses (MG), has been investigated by systematic experimental measurements coupled with theoretical calculations in Cu-Zr and Ni-Nb alloy systems. It is found that the atomic-level packing efficiency strongly relates to their GFA. The best GFA is located at the largest difference in the packing efficiency of the solute-centered clusters between the glassy and crystal alloys in both MG systems. This work provides an understanding of GFA from atomic level and will shed light on the development of new MGs with larger critical sizes.

Lipoxin A4 analog attenuates morphine antinociceptive tolerance, withdrawal-induced hyperalgesia, and glial reaction and cytokine expression in the spinal cord of rat.

Spinal neuroinflammation has been shown to play an important role in the development of morphine tolerance and morphine withdrawal-induced hyperalgesia. Lipoxins are endogenous lipoxygenase-derived eicosanoids that can function as "braking signals" in inflammation. The present study investigated the effect of 5 (S), 6 (R)-lipoxin A4 methyl ester (LXA4ME), a stable synthetic analog of lipoxin A4, on the expression of antinociceptive tolerance and withdrawal-induced hyperalgesia in chronic morphine-treated rats. Chronic morphine administration through repeated subcutaneous injection induced the development of hyperalgesia and the expression of spinal antinociceptive tolerance to morphine. However, LXA4ME treatment significantly attenuated the development of hyperalgesia and the expression of spinal antinociceptive tolerance to intrathecal morphine in both mechanical and thermal test. Moreover, the administration of LXA4ME during the induction of morphine tolerance inhibited the activation of microglia and astrocytes; reduced the expression of proinflammatory cytokines interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α); upregulated the expression of anti-inflammatory cytokines IL-10 and transforming growth factor-ß1 (TGF-ß1); and inhibited nuclear factor-kappa B (NF-κB) activation at the L5 lumbar spinal cord. These results suggest that treatment of LXA(4)ME provides a potential preventative or therapeutic approach for morphine tolerance and associated abnormal pain sensitivity.

Translocons on the inner and outer envelopes of chloroplasts share similar evolutionary origin in Arabidopsis thaliana.

The process of importing nuclear encoded proteins into chloroplasts is mediated by the Translocons on the Outer/Inner Envelope of Chloroplasts (TOC and TIC complex). The ancestor of the TOC complex was formed by pre-existing proteins from the cyanobacterial ancestor; other proteins recruited from the host cell or cyanobacterial ancestor were subsequently integrated into the complex. However, little is known about the origin of the TIC complex. In this work, the origin of the TIC complex was investigated through one of its channel proteins, AtTic21. Phylogenetic analysis suggested that AtTic21 is conserved in photosynthetic organisms. AtTic21 showed 33% sequence identity to a Synechocystis protein SynTic21. The successful genetic complementation of an AtTic21 knockout mutant by SynTic21 plus the transit peptide coding sequence of AtTic21 suggested that SynTic21 is an ortholog of AtTic21. The sequence and functional conservation between SynTic21 and AtTic21 suggested that the TIC complex shares a similar evolutionary origin to the TOC complex.

Hypotheses for the functions of intercellular bridges in male germ cell development and its cellular mechanisms.

In oogamous reproduction of multicellular organisms, a striking phenomenon is the prevailing synchronous development of male germ cells connected by wide intercellular bridges (IBs, 0.1-2 microm), which is well conserved in both animal and plant species ranging from algae to human. In the literature, IBs are believed either to allow genetically segregated haploid spermatids to share diploid gene products after meiosis, or to mediate rapid transfer of some vital signals or nutrients. Although intercellular sharing of gene transcripts has experimental evidences, these hypotheses are still not satisfactory. To explore the unknown roles of IB, we assume that developing male germ cells may be especially sensitive to stochastic gene expression to become heterogeneous. To achieve best gamete quality, such heterogeneity must be eliminated so that relatively uniform gametes with normal functions can be produced. Development within a common syncytium may be the only way for this purpose. The process may require not only the intercellular exchange of a few molecular signals but also the mixing of protoplasm between the connected cells so that they have similar levels/states of mRNAs, proteins and organelles, which can be achieved only through wide IBs. This hypothesis can explain some quite intriguing aspects of male gametogenesis and provide unique predictions that can be tested experimentally.

Effects of polyamines on organogenesis and somatic embryogenesis of Lycium barbarum calli.

Levels of three endogenous free polyamines (PAs), Put, Spd and Spm, were detected during organogenesis and somatic embryogenesis (SE) of Lycium barabrum (L.) calli. The predominant forms of PAs in organogenesis and SE were found to be Put and Spd, respectively. In both developmental pathways, the changes of Put content were very similar, i.e., it accumulated quickly in the initial stages of calli differentiation and then decreased; with the further morphogenesis, increase in Put level was also observed. The highest level of Spd was obtained at day 1 of calli organogenesis; while, after 1 day of culture for calli SE, Spd level began to increase and reached a maximum at day 10. The treatments with exogenous PAs had positive effects on both organogenesis and SE, especially those of Spd on organogenesis and SE and Put on SE. However, Put showed no effects on adventitious bud formation. CHA, which inhibits the activity of Spd synthetase, prevented both adventitious bud formation and further development of somatic embryo into plantlet. Although MGBG, a specific inhibitor of S-adenosyl methionine decarboxylases, had little effects on organogenesis, it reduced the number of somatic embryo and the plantlets subsequently regenerated. Such inhibitions could be reversed by Spd (50 mumol/L). These results from organogenesis and SE of the same specie indicate that PAs influenced these two in vitro morphogenesis pathways.