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Pleiotrophin (PTN) is a growth factor with both pro-angiogenic and limited pro-tumorigenic activity. We evaluated the potential for PTN to be used for safe angiogenic gene therapy using the full length gene and a truncated gene variant lacking the domain implicated in tumorigenesis. Mouse myoblasts were transduced to express full length or truncated PTN (PTN or T-PTN), along with a LacZ reporter gene, and injected into mouse limb muscle and myocardium. In cultured myoblasts, PTN was expressed and secreted via the Golgi apparatus, but T-PTN was not properly secreted. Nonetheless, no evidence of uncontrolled growth was observed in cells expressing either form of PTN. PTN gene delivery to myocardium, and non-ischemic skeletal muscle, did not result in a detectable change in vascularity or function. In ischemic hindlimb at 14 days post-implantation, intramuscular injection with PTN-expressing myoblasts led to a significant increase in skin perfusion and muscle arteriole density. We conclude that (1) delivery of the full length PTN gene to muscle can be accomplished without tumorigenesis, (2) the truncated PTN gene may be difficult to use in a gene therapy context due to inefficient secretion, (3) PTN gene delivery leads to functional benefit in the mouse acute ischemic hindlimb model.

Osteosarcoma is one of the most frequent types of primary malignant bone neoplasm in children and adolescents. Despite advancements developed in therapeutic modalities, the 5-year overall survival rates for patients with metastatic osteosarcoma disease remain poor. The present study aimed to investigate the expression level of microRNA-302a (miR-302a) in osteosarcoma tissues and cell lines, and the biological roles of miR-302a in osteosarcoma cells. In addition, the molecular mechanism underlying its tumor suppressive roles was evaluated. miR-302a expression in osteosarcoma tissues and cell lines was detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Following transfection of miR-302a mimics or IGF-1R siRNA, transwell migration and invasion, luciferase reporter assay RT-qPCR and western blot assays were conducted in osteosarcoma cells. In the present study, the data demonstrated that miR-302a was frequently reduced in osteosarcoma tissue and cell lines. In addition, the expression of miR-302a was correlated with metastatic features of patients with osteosarcoma. Restoration of miR-302a expression significantly inhibited the migration and invasion capacity of osteosarcoma cells. Mechanistic studies indicated that insulin-like growth factor 1 receptor (IGF-1R) was a direct target gene of miR-302a. Overexpression of miR-302a resulted in decreased expression of IGF-1R at the mRNA and protein levels. Furthermore, the knockdown IGF-1R mimicked the functions of miR-302a overexpression on osteosarcoma cell migration and invasion. Collectively, the results of the current study indicate that miR-302a acts as a metastasis suppressing miRNA and could be investigated as a therapeutic target for the treatment of patients with osteosarcoma to prevent metastasis. [ABSTRACT FROM AUTHOR]

A self-contained wireless current sensor applied for two-wire zip-cords is proposed in this paper, which consists of a Hall sensor, a wireless module, and an energy harvester along with the power management circuit. The energy harvester is constructed from a current transformer, where an EE-type magnetic core with two arms is specially designed by making a slit in one arm to produce unsymmetric field distributions: the field with low flux density is used for sensing and that with higher flux density for energy harvesting. In the energy scavenging operation, the sensor can generate 4.3 \mu \textW with a 217 $\Omega $ load resistor under 1 A zip-cord carrying current and supply power for the off-shelf Zig-bee nRF24LE1 wireless module to send one data for a time duration of about 5 min. In current-sensing operation, the sensor exhibits a sensitivity of 0.85 mV/A with a sensed current ranging from 1 A to 130 A. [ABSTRACT FROM PUBLISHER]

• Novelty: We propose a two-dimensional projection histogram assisted common phase error (CPE) compensation scheme in coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. We mathematically analyze the model of the CO-OFDM system and theoretically derive the principle of the proposed CPE compensation scheme. • Performance: Numerical simulations over the single mode fiber (SMF) transmission show that, compared to the pilot-aided (PA) estimation method, only less-overhead pilots were employed for our scheme, but more accurate CPE estimation can be achieved, hence improving the system performance. Moreover, to achieve an optimal transmission performance, the overhead of pilots for the PA method should be set to 20%, while the proposed method can reduce to 1.25%. • Impact: We proposed a semi-blind phase noise compensation algorithm (PA-2PH) for CO-OFDM systems based on two-dimensional projection histogram and low overhead pilots. Through numerical simulations' results, we find that for the 20Gb/s 16-QAM CO-OFDM systems after the 50km transmission, our scheme is more robust in EVM and BER performance than the PA and PH methods. Thus, our proposed CPE compensation scheme can provide enhanced transmission performance at a high spectrum efficiency and accuracy for CO-OFDM systems. In this paper, we demonstrate a two-dimensional projection histogram assisted common phase error (CPE) compensation scheme in coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. With the help of the low overhead pilots, the rough estimation can be obtained, and the π/2 deviation problem of projection histogram (PH) assisted scheme can be efficiently solved, which can improve the estimation accuracy of CPE. And, with the processing of the two-dimensional projection histogram mapping, the fine estimation can be achieved. The numerical CO-OFDM system simulations over the single mode fiber (SMF) transmission are conducted. The corresponding results show that, compared to the pilot-aided (PA) estimation method, only less-overhead pilots were employed for our scheme, but more accurate CPE estimation can be achieved, hence improving the system performance. Moreover, to achieve an optimal transmission performance, the overhead of pilots for the PA method should be set to 20%, while the proposed method can reduce to 1.25%. [ABSTRACT FROM AUTHOR]