Picosecond Spin Current Generation from Vicinal Metal-Antiferromagnetic Insulator Interfaces.

We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr_{2}O_{3} by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.

The role of miR-99b in mediating hepatocellular carcinoma invasion and migration.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "The role of miR-99b in mediating hepatocellular carcinoma invasion and migration, by C.-J. Liu, J.-H. Yang, F.-Z. Huang, J.-H. Yang, C.-P. Liu, X.-H. Mao, W.-M. Yi, X.-B. Shen, C. Peng, M.-F. Chen, B. Jiang, J.-S. Wu, published in Eur Rev Med Pharmacol Sci 2018; 22 (8): 2273-2281-DOI: 10.26355/eurrev_201804_14815-PMID: 29762829" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/14815.

The role of miR-99b in mediating hepatocellular carcinoma invasion and migration.

OBJECTIVE: Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults with a high rate of malignancy. The potent invasion and migration of HCC mainly impact the prognosis and recurrence of the disease. Our previous study found that miR-99b was highly expressed in HCC, and its expression was associated with vascular invasion. It was speculated that miR-99b may play a role in HCC invasion and migration, while the specific mechanism remains unclear. MATERIALS AND METHODS: qRT-PCR was applied to detect expressions of miR-99b and KAI1 genes in L02, HepG2, and MHCC97H cells. HepG2 cells were transfected with miR-99b inhibitor, miR-99b mimic, and NC. Flow cytometry was used to test cell cycle and apoptosis. Dual-luciferase reporter gene assay was adopted to validate the target gene of miR-99b. Wound healing assay was used to detect cell migration. Transwell assay was performed to detect cell invasion. Western blot was performed to detect KAI1, E-cadherin, and N-cadherin expressions. Immunofluorescence assay was adopted to test Vimentin expression. RESULTS: The level of miR-99b was reduced in L02 while up-regulated in MHCC97H. By contrast, the expression of KAI1 was increased in L02 but declined in MHCC97H. The transfection of miR-99b mimic inhibited HepG2 apoptosis and accelerated cell cycle. MiR-99b suppressed KAI gene expression through targeting its 3'-UTR. MiR-99b mimic or si-KAI1 transfection promoted cell invasion and migration, while their simultaneous action significantly enhanced cell invasion and migration. The overexpression of miR-99b or knockdown of KAI1 significantly weakened HepG2 cell adhesion, reduced E-cadherin expression, upregulated N-cadherin and Vimentin, and promoted cell epithelial-mesenchymal transition (EMT). CONCLUSIONS: MiR-99b contributes to promoting function in HCC migration and invasion through inhibiting KAI1 expression.

Stochastic WNT signaling between nonequivalent cells regulates adhesion but not fate in the two-cell leech embryo.

BACKGROUND: In the leech Helobdella robusta, an annelid worm, the early pattern of cell divisions is stereotyped. The unequal first cleavage yields cells AB and CD, which differ in size, cytoplasmic inheritance, normal fate, and developmental potential. RESULTS: Here we report a dynamic and transcription-independent pattern of WNT signaling in the two-cell stage of H. robusta. Surprisingly, HRO-WNT-A is first expressed in a stochastic manner, such that either AB or CD secretes the protein in each embryo. This stochastic phase is followed by a deterministic phase during which first AB, then CD expresses HRO-WNT-A. When contact between the cells is reduced or eliminated, both AB and CD express HRO-WNT-A simultaneously. Finally, bathing embryos in anti-HRO-WNT-A antibody during first cleavage reduces the adhesion between cells AB and CD. CONCLUSIONS: Our findings show that the stochastic phase of HRO-WNT-A signaling in the two-cell stage of Helobdella is negatively regulated by cell-cell contact and that this early signaling affects cell adhesion without affecting cell fate. We speculate that the primordial function of wnt class genes may have been to regulate cell-cell adhesion and that the nuclear signaling components of the wnt pathway arose later in association with the evolution of diverse cell types.

Segmentation of the central nervous system in leech.

Central nervous system (CNS) in leech comprises segmentally iterated progeny derived from five embryonic lineages (M, N, O, P and Q). Segmentation of the leech CNS is characterized by the formation of a series of transverse fissures that subdivide initially continuous columns of segmental founder cells in the N lineage into distinct ganglionic primordia. We have examined the relationship between the N lineage cells that separate to form the fissures and lateral ectodermal and mesodermal derivatives by differentially labeling cells with intracellular lineage tracers and antibodies. Although subsets of both lateral ectoderm and muscle fibers contact N lineage cells at or near the time of fissure formation, ablation experiments suggest that these contacts are not required for initiating fissure formation. It appears, therefore, that this aspect of segmentation occurs autonomously within the N lineage. To support this idea, we present evidence that fundamental differences exist between alternating ganglionic precursor cells (nf and ns primary blast cells) within the N lineage. Specifically, ablation of an nf primary blast cell sometimes resulted in the fusion of ipsilateral hemi-ganglia, while ablation of an ns primary blast cell often caused a 'slippage' of blast cells posterior to the lesion. Also, differences in cell behavior were observed in biochemically arrested nf and ns primary blast cells. Collectively, these results lead to a model of segmentation in the leech CNS that is based upon differences in cell adhesion and/or cell motility between the alternating nf and ns primary blast cells. We note that the segmentation processes described here occur well prior to the expression of the leech engrailed-class gene in the N lineage.

Cell fate determination in an annelid equivalence group.

In embryos of glossiphoniid leeches such as Helobdella triserialis and H. robusta, pairs of adjacent 'o/p' ectodermal blast cells are known to be developmentally equipotent and yet eventually contribute distinct sets of 'O' and 'P' progeny to the nervous system and epidermis of the mature leech. It has been thought that the fate-determining interactions in this 'O-P equivalence group' take place between the equipotent cells themselves. We show here that such intra-group interactions are neither necessary nor sufficient. Instead, transient contact with cells in another ectodermal lineage is necessary and sufficient to induce o/p blast cells to assume the P fate. In the absence of this contact they assume the O fate.

[Carcinoembryonic antigen and immunoglobin in gastric juice in the diagnosis of gastric cancer].

Levels of carcinoembryonic antigen (CEA) and immunoglobin (Ig) in gastric juice of 93 patients with benign and malignant gastric diseases were assayed. The CEA level in gastric cancer patients (55.73 +/- 38.26 ng/ml) was obviously higher than that in peptic ulcer (15.51 +/- 12.09 ng/ml) and superficial gastritis (26.96 +/- 20.17 ng/ml). But no significant difference was found between the CEA levels of gastric cancer and chronic atrophic gastritis (48.66 +/- 31.87 ng/ml). Also, elevated CEA was closely correlated to intestinal metaplasia. The positive rate of Ig was significantly higher in gastric cancer (IgG greater than or equal to 185 ug/ml, IgA greater than or equal to 100 ug/ml) than in benign gastric diseases. Although no correlation is present in the CEA and Ig in gastric juice, the combination of these two methods could improve the diagnostic accuracy. We believe that the two assays are worthy for screening gastric cancer from patients with high risk, and for identifying precancerous lesions.