Tug of War-Who is the Winner? Canker Disease Restructures the Endophytic Bacterial Community of Citrus

Jian-Yu Zhou,Yi Zhang,Wen-Ping Xu,Misbah Naz,Xiao-Meng Li,Xu Li,Bi-Ying Zhao,Shan-Shan Qi,Zhi-Cong Dai,Dao-Lin Du 한국원예학회 2023 원예과학기술지 Vol.41 No.5

Imaging Spectrum after Pancreas Transplantation with Enteric Drainage

Jian-Ling Chen,Rheun-Chuan Lee,Yi-Ming Shyr,Sing-E Wang,Hsiuo-Shan Tseng,Hsin-Kai Wang,Shan-Su Huang,Cheng-Yen Chang 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.1

Since the introduction of pancreas transplantation more than 40 years ago, surgical techniques and immunosuppressive regiments have improved and both have contributed to increase the number and success rate of this procedure. However, graft survival corresponds to early diagnosis of organ-related complications. Thus, knowledge of the transplantation procedure and postoperative image anatomy are basic requirements for radiologists. In this article, we demonstrate the imaging spectrum of pancreas transplantation with enteric exocrine drainage.

DYNAMIC PROGRAMMING FOR GENERAL LINEAR QUADRATIC OPTIMAL STOCHASTIC CONTROL WITH RANDOM COEFFICIENTS

( Shan Jian Tang ) 한국금융공학회 2014 한국금융공학회 학술발표회 Vol.2014 No.1

We are concerned with the linear-quadratic optimal stochastic control problem where all the coe_cients of the control system and the running weighting matrices in the cost functional are allowed to be predictable (but essentially bounded) processes and the terminal state-weighting matrix in the cost functional is allowed to be random. Under suitable conditions, we prove that the value field V (t, x, !), (t, x, !) ∈ [0, T] × Rn × , is quadratic in x, and has the following form: V (t, x) = hKtx, xi where K is an essentially bounded nonnegative symmetric matrix-valued adapted processes. Using the dynamic programming principle (DPP), we prove that K is a continuous semimartingale of the form and that (K, L) with L := (L1, ... ,Ld) is a solution to the associated backward stochastic Riccati equation (BSRE), whose generator is highly nonlinear in the unknown pair of processes. The uniqueness is also proved via a localized completion of squares in a self-contained manner for a general BSRE. The existence and uniqueness of adapted solution to a general BSRE was initially proposed by the French mathematician J. M. Bismut [in SIAM J. Control & Optim., 14(1976), pp. 419?444, and in S´eminaire de Probabilit´es XII, Lecture Notes in Math. 649, C. Dellacherie, P. A. Meyer, and M. Weil, eds., Springer-Verlag, Berlin, 1978, pp. 180?264], and subsequently listed by Peng [in Control of Distributed Parameter and Stochastic Systems (Hangzhou, 1998), S. Chen, et al., eds., Kluwer Academic Publishers, Boston, 1999, pp. 265?273] as the first open problem for backward stochastic di_erential equations. It had remained to be open until a general solution by the author [in SIAM J. Control & Optim., 42(2003), pp. 53?75] via the stochastic maximum principle with a viewpoint of stochastic flow for the associated stochastic Hamiltonian system. The present paper is its companion, and gives the second but more comprehensive (seemingly much simpler, but appealing to the advanced tool of Doob-Meyer decomposition theorem, in addition to the DDP) adapted solution to a general BSRE via the DDP. Further extensions to the jump-di_usion control system and to the general nonlinear control system are possible.

UNUSUAL ELECTROCHEMICAL RESPONSE OF ELECTROCHEMICAL ETCHING ON MULTIWALLED CARBON NANOTUBES

JIAN-SHAN YE,GUANGQUAN MO,WEI DE ZHANG,XIAO LIU,FWU-SHAN SHEU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.6

Multiwalled carbon nanotubes (MWNTs) can be etched at potentials more positive than 1.7 V versus Ag/AgCl (3 M KCl) in 0.2 M HNO3. The electrochemically etched MWNTs show an increase in electrochemical impedance and sluggish electron transfer kinetics, and lose the electrocatalytic effects toward the oxidation of glucose, H2O2, uric acid (UA) and L-ascorbic acid (L-AA). Transmission electron microscope (TEM) images reveal that the nanotube tips are cut off by electrochemical oxidation. This may lead to the degradation of electrocatalytic ability in the MWNTs. Furthermore, the current response after different electrochemically etched cycles shows that the electrocatalytic ability of the MWNTs toward different molecules can be tuned by etched cycles. For example, five etched cycles leads to the total disappearance of the oxidative response to L-AA, with the remaining over 50% of the UA current response in the L-AA and UA mixture. Thus, electrochemical etching is a simple yet novel way to tune the electrocatalytic reactivity and improve the selectivity of the MWNTs.

Higher-level Production of Ascomycin (FK520) by Streptomyces hygroscopicus var. Ascomyceticus Irradiated by Femtosecond Laser

Hai-shan Qi,Xing Xin,Shan-shan Li,Jian-ping Wen,Yun-lin Chen,Xiao-qiang Jia 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.4

Femtosecond laser irradiation technology was employed for the first time to improve the ascomycin (FK520)yield of Streptomyces hygroscopicus var. ascomyceticus NT2-11, which is an N-methyl-N-nitro-N-nitrosoguanidine (NTG)-induced strain derived from S. hygroscopicus (ATCC14891). The mutant FS35 with high and stable FK520 production capacity was then obtained in the optimal irradiation conditions (25 mW for 6 min) by the Titanium sapphire laser system (810 nm, 76 MHz, 150 fs). The FK520 production capacity of FS35 was 45% higher than that of the parental strain NT2-11. Moreover, under the optimal fermentation conditions, FK520 fermentation titer of FS35 reached 300 mg/L and the intrinsic kinetics of FS35 and NT2-11 were investigated comparatively in 3phases. The mathematical models provided a good description of FK520 fermentation process for both strains and valuable information for optimizing operation and pilotplant enlargement research. The comparative studies on parameters of the models confirmed the advantages in production and the decrease of substrate inhibition through femtosecond laser irradiation. Therefore, femtosecond laser irradiation provides a promising way to enhance the production of FK520 in S. hygroscopicus. Femtosecond laser irradiation technology was employed for the first time to improve the ascomycin (FK520)yield of Streptomyces hygroscopicus var. ascomyceticus NT2-11, which is an N-methyl-N-nitro-N-nitrosoguanidine (NTG)-induced strain derived from S. hygroscopicus (ATCC14891). The mutant FS35 with high and stable FK520 production capacity was then obtained in the optimal irradiation conditions (25 mW for 6 min) by the Titanium sapphire laser system (810 nm, 76 MHz, 150 fs). The FK520 production capacity of FS35 was 45% higher than that of the parental strain NT2-11. Moreover, under the optimal fermentation conditions, FK520 fermentation titer of FS35 reached 300 mg/L and the intrinsic kinetics of FS35 and NT2-11 were investigated comparatively in 3phases. The mathematical models provided a good description of FK520 fermentation process for both strains and valuable information for optimizing operation and pilotplant enlargement research. The comparative studies on parameters of the models confirmed the advantages in production and the decrease of substrate inhibition through femtosecond laser irradiation. Therefore, femtosecond laser irradiation provides a promising way to enhance the production of FK520 in S. hygroscopicus.

Antifibrotic Effect of Curcumin in TGF-β1-Induced Myofibroblasts from Human Oral Mucosa

Zhang, Shan-Shan,Gong, Zhao-Jian,Li, Wen-Hui,Wang, Xiao,Ling, Tian-You Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Background: Myofibroblasts play an important role in the development of oral submucous fibrosis (OSF). In the current study, we investigate the effect of curcumin on growth and apoptosis of myofibroblasts derived from human oral mucosa. Methods: Myofibroblasts were generated by incubating fibroblasts, obtained from human oral mucosa, with transforming growth factor-${\beta}1$ (TGF-${\beta}1$). MTT, PI staining, and FACS assays were used to investigate curcumin's effect on proliferation and cell cycle of fibroblasts and myofibroblasts. Annexin V/PI binding and FACS assays were used to examine apoptosis of myofibroblasts, Western blotting to determine the levels of Bcl-2 and Bax, and enzyme-linked immunosorbant assay was employed to examine the levels of collagen type I and III in the supernatants of myofibroblasts. Results: Curcumin inhibits proliferation of fibroblasts and myofibroblasts; it also disturbs the cell cycle, induces apoptosis and decreases the generation of collagen type I and III in myofibroblasts, which are more sensitive to its effects than fibroblasts. Curcumin induces apoptosis in myofibroblasts by down-regulating the Bcl-2/ Bax ratio. Conclusion: Our results demonstrate the antifibrotic effect of curcumin in vitro. It may therefore be a candidate for the treatment of OSF.

Down-regulation of miRNA-452 is Associated with Adriamycin-resistance in Breast Cancer Cells

Hu, Qing,Gong, Jian-Ping,Li, Jian,Zhong, Shan-Liang,Chen, Wei-Xian,Zhang, Jun-Ying,Ma, Teng-Fei,Ji, Hao,Lv, Meng-Meng,Zhao, Jian-Hua,Tang, Jin-Hai Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Adriamycin (ADR) is an important chemotherapeutic agent frequently used in treatment of breast cancer. However, resistance to ADR results in treatment failure in many patients. Recent studies have indicated that microRNAs (miRNAs) may play an important role in such drug-resistance. In the present study, microRNA-452 (miR-452) was found to be significantly down-regulated in adriamycin-resistant MCF-7 cells (MCF-7/ADR) compared with the parental MCF-7 cells by miRNA microarray and real-time quantitative PCR (RT-qPCR). MiR-452 mimics and inhibitors partially changed the adriamycin-resistance of breast cancer cells, as also confirmed by apoptosis assay. In exploring the potential mechanisms of miR-452 in the adriamycin-resistance of breast cancer cells, bioinformatics analysis, RT-qPCR and Western blotting showed that dysregulation of miR-452 played an important role in the acquired adriamycin-resistance of breast cancer, maybe at least in part via targeting insulin-like growth factor-1 receptor (IGF-1R).

Novel 5-Fluorouracil Derivatives: Synthesis and Cytotoxic Activity of 2-Butoxy-4-Substituted 5-Fluoropyrimidines

Jian Sun,Shi-Jie Zhang,Hai-Bo Li,Wei Zhou,Wei-Xiao Hu,Shang Shan 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.5

Twenty two new 5-fluorouracil (5-FU) derivatives, 2-butoxy-4-substituted 5-fluoropyrimidines, were synthesized and characterized by IR, 1H NMR, MS, HRMS. All compounds were preliminarily evaluated by MTT assay on human liver BEL-7402 cancer cell line in vitro. Ten compounds were selected to test their cytotoxic activity against A549, HL-60 and MCF-7 cancer cell lines in vitro. These compounds were more sensitive to BEL-7402 than other cell lines, particularly, cytotoxic activity of compounds 6b, 6d-f, 6p, 6s-u were in sub-micromolar scale. The highest cytotoxic potency against A549, HL-60 and MCF-7 was shown by 2-butoxy-4-chloro-5- fluoropyrimidine (5) with IC50 values of 0.10, 1.66 and 0.59 μM, respectively. Compounds 6d and 6e were effective against MCF-7 with IC50 9.73 μM and HL-60 with IC50 8.83 μM, respectively.

The role of protein arginine-methyltransferase 1 in gliomagenesis

( Shan Wang ),( Xiao Chao Tan ),( Bin Yang ),( Bin Yin ),( Jian Gang Yuan ),( Bo Qin Qiang ),( Xiao Zhong Peng ) 생화학분자생물학회(구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.8

Protein arginine methyltransferase 1 (PRMT1), a type-I arginine methyltransferase, has been implicated in diverse cellular events. We have focused on the role of PRMT1 in gliomagenesis. In this study, we showed that PRMT1 expression was up-regulated in glioma tissues and cell lines compared with normal brain tissues. The knock-down of PRMT1 resulted in an arrest in the G1-S phase of the cell cycle, proliferation inhibition and apoptosis induction in four glioma cell lines (T98G, U87MG, U251, and A172). Moreover, an in vivo study confirmed that the tumor growth in nude mouse xenografts was significantly decreased in the RNAi-PRMT1 group. Additionally, we found that the level of the asymmetric dimethylated modification of H4R3, a substrate of PRMT1, was higher in glioma cells than in normal brain tissues and decreased after PRMT1 knock-down. Our data suggest a potential role for PRMT1 as a novel biomarker of and therapeutic target in gliomas. [BMB Reports 2012; 45(8): 470-475]

Multiple gastrointestinal melanoma causing small bowel intussusception

Jian Yang Eng,Salehah Tahkin,Huzairi Yaacob,Nor Hayati Yunus,Ahmad Shan Wani Mohamed Sidek,Michael Pak-Kai Wong 대한대장항문학회 2023 Annals of Coloproctolgy Vol.39 No.1

A 61-year-old gentleman presented with small bowel intussusception from small bowel melanoma intussusceptum. He complains of intermittent abdominal distension but no history of intestinal obstruction. Apart from this, he was also symptomatic anemia which required repeated transfusion for the past few months. The contrast-enhanced computed tomography of the abdomen shows an omental mass with small bowel intussusception. He then underwent an exploratory laparotomy with segmental resection of the affected segment. Histopathological examination confirmed primary gastrointestinal melanoma. Multiple small bowel malignant melanoma is a rare disease. It remains a controversial diagnosis as it may be a primary or metastasis from an unidentified or regressed primary cutaneous melanoma. Prompt surgical intervention enables us to obtain tissue diagnosis, prevent complete intestinal obstruction and strategize the goals of treatment for the patient.