piRNA-1742 promotes renal cell carcinoma malignancy by regulating USP8 stability through binding to hnRNPU and thereby inhibiting MUC12 ubiquitination

Zhang Wentao,Zheng Zongtai,Wang Keyi,Mao Weipu,Li Xue,Wang Guangchun,Zhang Yuanyuan,Huang Jianhua,Zhang Ning,Wu Pengfei,Liu Ji,Zhang Haimin,Che Jianping,Peng Bo,Zheng Junhua,Li Wei,Yao Xudong 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Accumulating studies have confirmed that PIWI-interacting RNAs (piRNAs) are considered epigenetic effectors in cancer. We performed piRNA microarray expression analysis on renal cell carcinoma (RCC) tumor tissues and paired normal tissues and performed a series of in vivo and in vitro experiments to explore piRNAs associated with RCC progression and investigate their functional mechanisms. We found that piR-1742 was highly expressed in RCC tumors and that patients with high piR-1742 expression had a poor prognosis. Inhibition of piR-1742 significantly reduced tumor growth in RCC xenograft and organoid models. Mechanistically, piRNA-1742 regulates the stability of USP8 mRNA by binding directly to hnRNPU, which acts as a deubiquitinating enzyme that inhibits the ubiquitination of MUC12 and promotes the development of malignant RCC. Subsequently, nanotherapeutic systems loaded with piRNA-1742 inhibitors were found to effectively inhibit the metastasis and growth of RCC in vivo. Therefore, this study highlights the functional importance of piRNA-related ubiquitination in RCC and demonstrates the development of a related nanotherapeutic system, possibly contributing to the development of therapeutic approaches for RCC.

Fast Partial Shading Analysis of Large-scale Photovoltaic Arrays via Tearing Method

Zhang, Mao,Zhong, Sunan,Zhang, Weiping The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

Partial shading analysis of large-scale photovoltaic (PV) arrays has recently become a theoretically and numerically challenging issue, and it is necessary for PV system designers. The main contributions of this study are the following: 1) A PSIM-based macro-model was employed because it is remarkably fast, has high precision, and has no convergence issues. 2) Three types of equivalent macro-models were developed for the transformation of a small PV sub-array with uniform irradiance to a new macro-model. 3) On the basis of the proposed new macro-model, a tearing method was established, which can divide a large-scale PV array into several small sub-arrays to significantly improve the efficiency improvement of a simulation. 4) Three platforms, namely, PSIM, PSpice, and MATLAB, were applied to evaluate the proposed tearing method. The proposed models and methods were validated, and the value of this research was highlighted using an actual large-scale PV array with 2420 PV modules. Numerical simulation demonstrated that the tearing method can remarkably improve the simulation efficiency by approximately thousands of times, and the method obtained a precision of nearly 6.5%. It can provide a useful tool to design the optimal configuration of a PV array with a given shading pattern as much as possible.

Trans-arterial Chemo-Embolization in Treating Elderly Patients with Hepatocellular Carcinoma

Zhang, Jian-Feng,Liu, Jun-Mao,Zhang, Nin,Du, Chao,Zheng, Qin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.16

Background: This analysis was conducted to evaluate the efficacy and safety of Trans-arterial Chemo-Embolization (TACE) in treating Elderly patients with Hepatocellular Carcinoma (EHPC). Methods: Clinical studies evaluating the efficacy and safety of TACE on response and safety for patients with EHPC were identified by using a predefined search strategy. Pooled response rate of treatment were calculated. Results: In TACE based regimen, clinical studies which including patients with EHPC were considered eligible for the evaluation of response. And, in these TACE based treatments, pooled analysis suggested that, in all 288 patients whose response could be assessed, the pooled reponse rate was 29.5%(85/288) in TACE based treatment. The most commonly encountered TACE-related morbidity was liver function impairment. No grade III or IV renal or liver toxicity were observed. No treatment related death occurred in EHPC patients with TACE based treatments. Conclusion: This evidence based analysis suggests that TACE based treatments are associated with mild response rate and accepted toxicities for treating patients with EHPC.

A Canonical Small-Signal Linearized Model and a Performance Evaluation of the SRF-PLL in Three Phase Grid Inverter System

Mao, Peng,Zhang, Mao,Zhang, Weiping The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.5

Phase-locked loops (PLL) based on the synchronous reference frame (SRF-PLL) have recently become the most widely-used for grid synchronization in three phase grid-connected inverters. However, it is difficult to study their performance since they are nonlinear systems. To estimate the performances of a SRF-PLL, a canonical small-signal linearized model has been developed in this paper. Based on the proposed model, several significant specifications of a SRF-PLL, such as the capture time, capture rang, bandwidth, the product of capture time and bandwidth, and steady-state error have been investigated. Finally, a noise model of a SRF-PLL has been put forward to analyze the noise rejection ability by computing the SNR (signal-to-noise ratio) of a SRF-PLL. Several simulation and experimental results have been provided to verify and validate the obtained conclusions. Although the proposed model and analysis method are based on a SRF-PLL, they are also suitable for analyzing other types of PLLs.

Solution to Some Key Problems of Self-exciting Electronic Ballast

Mao, Peng,Zhang, Weiping,Zhang, Mao The Korean Institute of Electrical and Electronic 2014 Transactions on Electrical and Electronic Material Vol.15 No.1

Self-exciting electronic ballast, of small size, and low cost, and high power, with no stroboscopic effect, no noise, is widely used in the general lighting market. This paper describes the cause of high switching loss of self-exciting electronic ballast, based on its operational principle; then, to reduce the switch temperature and increase the reliability of the product, the drive circuit has been improved, to achieve soft-switching. The theory analysis, simulation and experimental result prove the feasibility and compatibility of this new method in practice. Finally, the design procedure and winding method of the self-exciting current transformer are introduced.

Seniors Have a Better Learning Curve for Laparoscopic Colorectal Cancer Resection

Zhang, Xing-Mao,Wang, Zheng,Liang, Jian-Wei,Zhou, Zhi-Xiang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Purpose: This study was designed to evaluate the outcomes of laparoscopic colorectal resection in a period of learning curve completed by surgeons with different experience and aptitudes with a view to making clear whether seniors had a better learning curve compared with juniors. Methods: From May 2010 to August 2012, the first twenty patients underwent laparoscopic colorectal resection completed by each surgeon were selected for analysis retrospectively. A total of 240 patients treated by 5 seniors and 7 juniors were divided into the senior group (n=100) and the junior group (n=140). The short-term outcomes of laparoscopic surgery of the two groups were compared. Results: The mean numbers of lymph nodes harvested were $21.2{\pm}11.0$ in the senior group and $17.3{\pm}11.5$ in the junior group (p=0.010); The mean operative times were $187.9{\pm}60.0min$ as compared to $231.3{\pm}55.7min$ (p=0.006), and blood loss values were $177.0{\pm}100.7ml$ and $234.0{\pm}185ml$, respectively (p=0.001); Conversion rate in the senior group was obviously lower than in the junior group (10.0% vs 20.7%, p=0.027) and the mean time to passing of first flatus were $3.3{\pm}0.9$ and $3.8{\pm}0.9$ days (p=0.001). For low rectal cancer, the sphincter preserving rates were 68.7% and 35.3% (p=0.027). Conclusions: Seniors could perform laparoscopic colorectal resection with relatively better oncological outcomes and quicker recovery, and seniors could master the laparoscopic skill more easily and quickly. Seniors had a better learning curve for laparoscopic colorectal cancer resection compared to juniors.

RUIN PROBABILITIES IN THE RISK MODEL WITH TWO COMPOUND BINOMIAL PROCESSES

Zhang, Mao-Jun,Nan, Jiang-Xia,Wang, Sen Korean Society of Computational and Applied Mathem 2008 Journal of applied mathematics & informatics Vol.26 No.1

In this paper, we consider an insurance risk model governed by a compound Binomial arrival claim process and by a compound Binomial arrival premium process. Some formulas for the probabilities of ruin and the distribution of ruin time are given, we also prove the integral equation of the ultimate ruin probability and obtain the Lundberg inequality by the discrete martingale approach.

A New Unsymmetrical Zinc Phthalocyanine as Photosensitizers for Dye-sensitized Solar Cells

Zhang, Dan,Zhang, Xue-Jun,Zhang, Lei,Mao, Li-Jun Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.4

A new unsymmetrical zinc phthalocyanine has been designed and synthesized based on the 'push-pull' and extended ${\pi}$-conjugation concept for the dye-sensitized solar cells. Three tert-butoxy groups, which act as electron releasing ('push'), enhance the solubility of phthalocyanine in common organic solvents and reduce the aggregation. Hydroxy substituted 9,10-anthraquinones act as electron acceptors ('pull') for the study of photoinduced electron transfer processes as well as grafting onto nanocrystalline $TiO_2$. The new unsymmetrical zinc phthalocyanine was fully characterized by FTIR, UV-vis, $^1H$ NMR, cyclic voltammetry and differential pulse voltammetry. The new sensitizer was tested in dye-sensitized solar cells, and gave a better performance.

Advantages of Laparoscopic Abdominoperineal Resection for Anastomotic Recurrence of Rectal Cancer

Zhang, Xing-Mao,Wang, Zheng,Ma, Sheng-Hui,Zhou, Zhi-Xiang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

Background: Surgery offers the only potential for cure and long-term survival of recurrence of rectal cancer. Few studies about laparoscopic recurrent lesion resection have been reported. This study was designed to evaluate the safety and feasibility of laparoscopic abdomino-perineal resection for anastomotic recurrence of rectal cancer. Materials and Methods: Data for 42 patients with recurrence of rectal cancer were collected retrospectively. Of the 42 patients, 22 underwent laparoscopic surgery (LR group) and 20 received open surgery (OR group). Outcomes between the two groups were compared. Results: Operation time in LR group was shorter compared with the OR group ($164.6{\pm}27.7min$ vs $203.0{\pm}45.3min$); intra-operative blood loss was $119.7{\pm}44.4ml$ and $185.0{\cdot}94.0ml$ in LR group and OR group, respectively (p<0.001); time to first flatus in LR group was shorter than in OR group, and the difference was statistically significant ($2.6{\pm}0.8$ days vs $3.1{\pm}0.8$ days, p=0.013); hospital stay in the LR and OR groups was $8.6{\pm}1.3$ days and $9.8{\pm}2.2$ days; 3-year survival rates in the LR and OR groups were 44.4% and 42.8% (p=0.915) and the 3-year disease-free survival rates were 36.4% and 30.0%, respectively (p=0.737). Conclusions: Laparoscopic abdomino-perineal resection is safe and feasible for anastomotic recurrence of rectal cancer.

Analysis of Laparoscopy-assisted Gastric Cancer Operations Performed by Inexperienced Junior Surgeons

Zhang, Xing-Mao,Wang, Zheng,Liang, Jian-Wei,Zhou, Zhi-Xiang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

To clarify whether gastric cancer patients can benefit from laparoscopy-assisted surgery completed by junior surgeons under supervision of expert surgeons, data of 232 patients with gastric cancer underwent operation performed by inexperienced junior surgeons were reviewed. Of the 232 patients, 137 underwent laparoscopy-assisted resection and in 118 cases this approach was successful. All of these 118 patients were assigned to laparoscopic group in this study, 19 patients who were switched to open resection were excluded. All laparoscopic operations were performed under the supervision of expert laparoscopic surgeons. Some 95 patients receiving open resection were assigned to the open group. All open operations were completed independently by the same surgeons. Short-term outcomes including oncologic outcomes, operative time intra-operative blood loss, time to first flatus, time to first defecation, postoperative hospital stay and perioperative complication were compared between the two groups. The numbers of lymph nodes harvested in the laparoscopic and open groups were $21.1{\pm}9.6$ and $18.2{\pm}9.7$ (p=0.029). There was no significant difference in the length of margins. The mean operative time was $215.9{\pm}32.2$ min in laparoscopic group and $220.1{\pm}34.6min$ in the open group (p=0.866), and the mean blood loss in laparoscopic group was obviously less than that in open group ($200.9{\pm}197.0ml$ vs $291.1{\pm}191.4ml$; p=0.001). Time to first flatus in laparoscopic and open groups was $4.0{\pm}1.0$ days and $4.3{\pm}1.2$ days respectively and the difference was not significant (p=0.135). Similarly no statically significant difference was noted for time to first defecation ($4.7{\pm}1.6$ vs $4.8{\pm}1.6$, p=0.586). Eleven patients in the laparoscopic group and 19 in the open group suffered from peri-operative complications and the difference between the two groups was significant (9.3% vs 20.0%, p=0.026). The conversion rate for laparoscopic surgery was 13.9%. Patients with gastric cancer can benefit from laparoscopy-assisted operations completed by inexperienced junior surgeons under supervision of expert laparoscopic surgeons.