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Serotonin is a monoamine neurotransmitter that has multiple extraneuronal functions. We previously reported that serotonin exerted mitogenic stimulation on megakaryocytopoiesis mediated by 5-hydroxytryptamine (5-HT) 2 receptors. In this study, we investigated effects of serotonin on ex vivo expansion of human cord blood CD34

Background Jujube (Ziziphus jujuba Mill.) fruit is one of the largest productions in China and its increasing production has drawn considerable attention from researchers. Polysaccharide is one of the most abundant components of jujube, and it represents a major group of biolotegically active constituents. This study intended to investigate the special structure of a homogeneous acidic polysaccharide (PZMP4) produced from Ziziphus Jujuba cv. Muzao fruit using novel methods, including DEAE-Sepharose Fast Flow and Sephacryl S-300 column chromatography. Results The structure of PZMP4 was determined via high-performance gel permeation chromatography (HPGPC), gas chromatography (GC), Fourier transform infrared spectroscopy (FT-IR), methylation analysis, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The results reveal that PZMP4 with a molecular weight of 27.90 kDa was composed of rhamnose, arabinose, mannose, glucose, galactose, and galacturonic acid at a ratio of 2.32:2.21:0.22:0.88:2.08:8.83. Advanced structural analysis revealed a netted structure with molecular aggregates of PZMP4. Structural features demonstrated that the basic backbone of PZMP4 appeared to mainly consist of (1→4)-linked GalpA with three branches bonded to O-3 of (1→3)-linked Araf, (1→2)-linked Rhap, and terminated with GalpA. Conclusions PZMP4’s unique structure could imply distinct bioactivities and have considerable utilization in functional food. Graphic abstract

Our previous studies have shown that serotonin (5-hydroxytryptamine; 5-HT) is a growth factor for hematopoietic stem/progenitor cells. In this study, we proposed a possible mechanism: 5-HT may enhance megakaryopoiesis and proplatelet formation via Erk1/2 pathway and cytoskeleton reorganization. Here, 5-HT 2B R was first identified in megakaryocytic cells. 5-HT also promoted the megakaryocytes (MKs) proliferation and reduced the cell apoptosis via the activation of 5-HT 2B R and Akt pathway. The effects were reduced by the 5-HT 2B R inhibitor ketanserin. The effect of 5-HT on proplatelet formation in bone marrow MKs were further confirmed: the 5-HT treated group had more proplatelet bearing MKs compared with the control group. To determine whether 5-HT has effects on cytoskeleton reorganization of MKs, and whether these effects could be reduced by ketanserin or Erk1/2 inhibitor PD98059, MKs were stained with the F-actin specific binder rhodamine-phalloidin. The polymerized actin level was lower in the control group than the 5-HT group and was distributed throughout the cytoplasm with occasional aggregations. Our data demonstrated that Erk1/2 was activated in MKs treated with 5-HT. This study suggests that 5-HT has a potent effect on platelet formation and this effect is likely mediated via 5HT 2B R with subsequent activation of p-Erk1/2 and consequent F-actin reorganization and proplatelet formation. We also demonstrated that melatonin, the metabolite of 5-HT, exerts a protective effect on MK and platelet recovery in the irradiated mouse model. This study suggested that 5-HT plays an important role in platelet formation via 5HT 2B R, p-Erk1/2, and F-actin reorganization.

Mobile and slow-moving operations, such as striping, sweeping, bridge flushing, and pothole patching, are critical for efficient and safe operation of a highway transportation system. However, reducing hazards for roadway workers and achieving a safer environment for both roadway maintenance operators and the public is a challenging problem. In 2017 alone, a total of 158,000 vehicle crashes occurred in work zones in the U.S.A., accounting for 61,000 injuries. The autonomous truck-mounted attenuator (ATMA) vehicle, sometimes referred to as an autonomous impact protection vehicle (AIPV), offers a promising solution to eliminate injuries to roadway maintenance workers and the public. This paper presents the evaluation methodology for the ATMA system, as well as the outcomes of field testing in Sedalia, Missouri. To the best of the authors’ knowledge, this is the first academic research to focus on ATMA. The ATMA system is first reviewed, followed by an introduction to the field testing procedures that includes descriptions of test cases and data collected, and their format. An analysis methodology is then proposed to quantitatively evaluate the system’s performance, and statistical models and hypothesis testing procedures are developed and presented. The numerical analysis results from real-world field testing under a controlled environment are presented, and the ATMA system’s performance is summarized. This paper can serve as a reference for transportation agencies that are interested in deploying similar technologies or for academic researchers to assess characteristics of autonomous vehicles and to apply knowledge gained in transportation modeling and simulation practices.