Plexin B3 guides axons to cross the midline in vivo.

During the development of neural circuits, axons are guided by a variety of molecular cues to navigate through the brain and establish precise connections with correct partners at the right time and place. Many axon guidance cues have been identified and they play pleiotropic roles in not only axon guidance but also axon fasciculation, axon pruning, and synaptogenesis as well as cell migration, angiogenesis, and bone formation. In search of receptors for Sema3E in axon guidance, we unexpectedly found that Plexin B3 is highly expressed in retinal ganglion cells of zebrafish embryos when retinal axons are crossing the midline to form the chiasm. Plexin B3 has been characterized to be related to neurodevelopmental disorders. However, the investigation of its pathological mechanisms is hampered by the lack of appropriate animal model. We provide evidence that Plexin B3 is critical for axon guidance in vivo. Plexin B3 might function as a receptor for Sema3E while Neuropilin1 could be a co-receptor. The intracellular domain of Plexin B3 is required for Semaphorin signaling transduction. Our data suggest that zebrafish could be an ideal animal model for investigating the role and mechanisms of Sema3E and Plexin B3 in vivo.

Research Progress in Pharmacological Mechanisms, Structure-Activity Relationship and Synthesis of Sartans.

The sartans are a new class of antihypertensive drugs as angiotensin II receptor blockers which possess plenty of advantages in treating hypertension and related pathologies. This review describes the clinical treatment, side effects, and potential therapeutic effects of sartans from 1995 to date. The synthesis, structural-activity and molecular docking with Angiotensin Type 1 receptor of imidazole derivatives, benzimidazole derivatives and other compounds are also described. With a clear Structure-Activity Relationship and abundant pharmacological effects, some types of novel Angiotensin Type 1 receptor antagonists are emerging gradually for further research in the meantime.

[Study on the Therapeutic Effect of Lenalidomide on Hemophilic Arthropathy].

OBJECTIVE: To explore the effect of lenalidomide on human fibroblast-like synovial cells (HFLS) and the therapeutic efficacy on hemophilic arthropathy in hemophilia A mice model. METHODS: In vitro, to remodel the inflammatory environment of synovial tissue after hemorrhage, ferric citrate and recombinant TNF-α were added into the cell culture medium of HFLS. Cell Counting Kit-8 (CCK-8), Enzyme-linked immunosorbent assay (ELISA), Quantitative Real-time PCR (RT-qPCR) and flow cytometry were employed for detection of the effects of lenalidomide on the proliferation ability, pro-inflammatory cytokines release and apoptosis of HFLS cells. In vivo, hemophilia arthropathy was remodeled in hemophilia A mice by induction of hemarthrosis. A series of doses of lenalidomide (0.1, 0.3 and 1.0 g/kg) was administrated intra-articularly. Tissues of knee joints were collected on the 14th day after administration, and the protective effect of lenalidomide on arthritis in hemophilia A mice were evaluated by RT-qPCR and histological grading. RESULTS: In vitro, compared with the untreated control group, lenalidomide could significantly inhibit the proliferation of HFLS cells (P<0.05), and the effect was the most significant when the concentration was 0.01 µmol/L (P<0.001). Compared with the control group, lenalidomide could significantly inhibit the expression levels of TNF-α, IL-1ß, IL-6 and IFN-γ in HFLS cells (P<0.05). The flow cytometry results showed that lenalidomide could enhance the apoptotis of HFLS cells (P<0.05). The results of RT-qPCR showed that lenalidomide could significantly reduce the mRNA expression levels of TNF-α, IL-1ß, IL-6,MCP-1 and VEGF in the joint tissues (P<0.05). Histological results showed that compared with the injured group, lenalidomide could significantly reduce the pathological sequela after hemarthrosis induction, e.g. synovial thickening and neo-angiogenesis in the synovium. The protection displayed a dose-response pattern roughly. CONCLUSION: In vitro, lenalidomide can inhibit the proliferation of HFLS cells, promote their apoptosis, and inhibit the expression of pro-inflammatory cytokines. In vivo, lenalidomide can significantly decrease the expression of pro-inflammatory cytokines in the joints of mice, and prevent the development of inflammation and neo-angiogenesis. The results provide a theoretical and experimental basis for the clinical application of lenalidomide in the treatment of hemophilic arthropathy.

SCSit: A high-efficiency preprocessing tool for single-cell sequencing data from SPLiT-seq.

SPLiT-seq provides a low-cost platform to generate single-cell data by labeling the cellular origin of RNA through four rounds of combinatorial barcoding. However, an automatic and rapid method for preprocessing and classifying single-cell sequencing (SCS) data from SPLiT-seq, which directly identified and labeled combinatorial barcoding reads and distinguished special cell sequencing data, is currently lacking. Here, we develop a high-efficiency preprocessing tool for single-cell sequencing data from SPLiT-seq (SCSit), which can directly identify combinatorial barcodes and UMI of cell types and obtain more labeled reads, and remarkably enhance the retained data from SCS due to the exact alignment of insertion and deletion. Compared with the original method used in SPLiT-seq, the consistency of identified reads from SCSit increases to 97%, and mapped reads are twice than the original. Furthermore, the runtime of SCSit is less than 10% of the original. It can accurately and rapidly analyze SPLiT-seq raw data and obtain labeled reads, as well as effectively improve the single-cell data from SPLiT-seq platform. The data and source of SCSit are available on the GitHub website https://github.com/shang-qian/SCSit.

Comparative Brain and Central Nervous System Tumor Incidence and Survival between the United States and Taiwan Based on Population-Based Registry.

PURPOSE: Reasons for worldwide variability in the burden of primary malignant brain and central nervous system (CNS) tumors remain unclear. This study compares the incidence and survival of malignant brain and CNS tumors by selected histologic types between the United States (US) and Taiwan. METHODS: Data from 2002 to 2010 were selected from two population-based cancer registries for primary malignant brain and CNS tumors: the Central Brain Tumor Registry of the United States and the Taiwan Cancer Registry. Two registries had similar process of collecting patients with malignant brain tumor, and the quality of two registries was comparative. The age-adjusted incidence rate (IR), IR ratio, and survival by histological types, age, and gender were used to study regional differences. RESULTS: The overall age-adjusted IRs were 5.91 per 100,000 in the US and 2.68 per 100,000 in Taiwan. The most common histologic type for both countries was glioblastoma (GBM) with a 12.9% higher proportion in the US than in Taiwan. GBM had the lowest survival rate of any histology in both countries (US 1-year survival rate = 37.5%; Taiwan 1-year survival rate = 50.3%). The second largest group was astrocytoma, excluding GBM and anaplastic astrocytoma, with the distribution being slightly higher in Taiwan than in the US. CONCLUSION: Our findings revealed differences by histological type and grade of primary malignant brain and CNS tumors between two sites.