Diverse mode operation fiber laser mode-locked by nonlinear multimode interference.

We present an all-fiber passively mode-locked (ML) laser with a nonlinear multimode interference (NLMI)-based saturable absorber (SA) capable of generating five pulse modes. The SA consists of two centrally aligned graded index multimode fiber (GIMF) with different diameters (105-50 µm) and features a widely adjustable transmission with saturable/reverse-saturable absorption. Based on this, dissipative soliton (DS), Q-switched rectangular pulse (QRP), dissipative soliton resonance (DSR), noise-like pulse (NLP) and bright-dark pulse pairs (BDP) are observed at three dispersions without additional filter. The DS has a pulse energy, bandwidth and duration of up to 1.15 nJ, 17.98 nm and ∼2.78 ps. The achievable pulse duration and energy of DSR and NLP are 5.21, 48.06 ns and 4.53, 5.12 nJ, respectively. Furthermore, it is demonstrated that the BDP is superimposed by a chair-case pulse (CP) and a rectangular pulse (RP) belonging to orthogonal polarization states. The versatility, flexibility, simplicity and energy scalability of the large-core hybrid GIMF-SA, make it interesting and highly attractive in ultrafast photonics.

Ultra-sensitive pressure sensor with low-temperature crosstalk based on the Vernier effect and helical structure.

What we believe to be a novel high-sensitivity fiber-optic pressure sensor based on the vernier effect and helical structure is proposed and experimentally verified. The sensor utilizes the superposition of higher-order mode Mach-Zehnder interference and Sagnac fundamental mode polarization interference in a single fiber ring to achieve the vernier effect. In addition, a non-invasive encapsulation structure was fabricated to convert the rise and fall of the pressure value into the change in the twist angle of the optical fiber. This approach reduces the interference of the detecting medium on the sensor signal while simultaneously increasing the sensitivity of the pressure sensor. According to experimental data, the detection sensitivity of the sensor can reach -67277 nm/MPa, which is 65 times higher than the sensitivity of the conventional vernier effect pressure sensor. It also solves the issue of temperature interference with the Vernier-effect structured fiber optic sensor. The sensor has a measured temperature cross-sensitivity of 0.000065 kPa/°C, which is significantly lower than that of comparable sensors. This makes the sensor highly sensitive and ideal for low crosstalk pressure measurement.

Generation of multiple solitons with controllable separation assisted by PM fiber.

A method of generating multiple solitons with controllable separation is proposed by injecting the dissipative soliton (DS) and conventional soliton (CS) into the polarization-maintaining fiber (PMF), respectively. The soliton separation can be adjusted subjectively from 12 to 28 ps, corresponding to PMF lengths from 10 to 24 m. Multiple solitons consisting of three, four, five, and six solitons can be observed at pump powers of 480, 550, 610, and 700 mW. DS's average single-pulse energy can increase from 20.4 to 40.7 pJ, while the average single-pulse energy of CS decreases from 29.3 to 13.7 pJ. The experimental results can contribute to the further understanding of the dynamics of multiple solitons.

C/EBPß enhances efficacy of sorafenib in hepatoblastoma.

Hepatoblastoma (HB) is the predominant hepatic neoplasm in infants and young children. Sorafenib has been used to treat adult and pediatric hepatocellular carcinoma. However, efficacy of monotherapy of sorafenib in HB is not sustained. In this study, we tested a possible combinatory therapy of sorafenib with the CCAAT/enhancer-binding proteins (C/EBP) overexpression in HB cell line. Firstly, we evaluated the expression level of C/EBPß in the patients with HB by analyzing The Cancer Genome Atlas data. Lower level of C/EBPß was observed in tumor tissues in comparison with matched normal tissues. Next, we observed that combination of sorafenib and C/EBPß overexpression led to dramatic growth and migration inhibition of live tumor cells which implied promising probability for clinical trial. Mechanistically, C/EBPß which can be downregulated by Ras v12, augmented messenger RNA and protein levels of p53. These data suggested that a combination of sorafenib and C/EBPß overexpression inhibited tumor growth synergistically and provided a promising approach to treat HB.

MiR-27a-3p/Hoxa10 Axis Regulates Angiotensin II-Induced Cardiomyocyte Hypertrophy by Targeting Kv4.3 Expression.

Cardiac hypertrophy is a common pathological process of various cardiovascular diseases, which is often accompanied with structural and electrical remodeling, and can even lead to sudden cardiac death. However, its molecular mechanism still remains largely unknown. Here, we induced cardiomyocyte hypertrophy by angiotensin II (Ang II), and found that miR-27a-3p and hypertrophy-related genes were up-regulated. Further studies showed that miR-27a-3p-inhibitor can alleviate myocardial hypertrophy and electrical remodeling. Moreover, luciferase assay confirmed that miR-27a-3p could regulate the expression of downstream Hoxa10 at the transcriptional level by targeting at its 3'UTR. At the same time, the protein expression of Hoxa10 was significantly reduced in Ang II-treated cardiomyocytes. Furthermore, overexpression of Hoxa10 can reverse myocardial hypertrophy and electrical remodeling induced by Ang II in cardiomyocytes. Finally, we found that Hoxa10 positively regulated the expression of potassium channel protein Kv4.3 which was down-regulated in hypertrophic cardiomyocytes. Taken together, our results revealed miR-27a-3p/Hoxa10/Kv4.3 axis as a new mechanism of Ang II-induced cardiomyocyte hypertrophy, which provided a new target for clinical prevention and treatment of cardiac hypertrophy and heart failure.

[Polymorphism of vitamin D receptor Fok I and colorectal cancer risk in Chinese].

OBJECTIVE: To explore the frequency of vitamin D receptor (VDR) Fok I polymorphism in healthy Chinese and colorectal tumor patients,and to study the correlation between VDR Fok I polymorphism and the pathogenesis of colorectal tumor. METHODS: After the preparation of gDNA by common method,VDR genotypes were determined by Fok I restriction endonuclease digestion of PCR-amplified DNA in 69 colorectal cancer patients and 218 healthy persons. RESULTS: The F allele frequencies of VDR in healthy persons and in colorectal tumors patients were 61.5% and 49.3%, respectively, with statistical difference (P< 0.05). The genotype frequencies of FF, Ff and ff in healthy persons and in colorectal tumors patient were (39.5%,44%,16.5%) and (29.1%,40.5%,30.4%), respectively,with statistical differences (P< 0.05). The odds ratio of ff and Ff genotypes were 2.51 (95% confidence interval,1.21 approximately 5.18) and 2.00 (95% confidence intervals,1.01approximately 3.96), respectively (P< 0.01). CONCLUSION: Fok I polymorphism is a common single nucleotide polymorphism (SNP) of VDR in Chinese population,and the VDR Fok I polymorphism may lower the risk of colorectal tumor.