Effect of inorganic mesoporous carriers on 1-palmitoyl-2-linoleoyl-3-acetyl-<i>rac</i>-glycerol-loaded solid self-emulsifying drug delivery system: Physicochemical characterization and bioavailability in rats

Kim, Dong Shik,Yang, Eun Su,Yong, Chul Soon,Youn, Yu Seok,Oh, Kyung Taek,Li, Dong Xun,Kim, Jong Oh,Jin, Sung Giu,Choi, Han-Gon Elsevier 2017 Colloids and Surfaces B Vol.160 No.-

<P><B>Abstract</B></P> <P>The purpose of this study was to assess the impact of inorganic mesoporous carriers on the physicochemical properties and oral bioavailability of 1-palmitoyl-2-linoleoyl-3-acetyl-<I>rac</I>-glycerol (PLAG)-loaded solid self-emulsifying drug delivery system (solid SEDDS). Numerous PLAG-loaded solid SEDDS formulations were prepared by spray drying technique with sodium laurylsulfate (SLS), butylated hydroxyanisole (BHA) and inorganic mesoporous materials as a surfactant, antioxidant and solid carrier, respectively. The mesoporous materials, such as calcium silicate, silicon dioxide and magnesium aluminosilicate were used as the solid carriers. Their physicochemical properties, solubility, dissolution and pharmacokinetic studies in rats were performed compared with drug alone. Three solid SEDDSs composed of PLAG/BHA/SLS/mesopous carrier at the weight ratio of 1:0.0002:0.25:0.5 resulted in a small emulsion droplet and excellent drug loading efficiency. The solid SEDDS formulations prepared with calcium silicate and silicon dioxide showed a rough-surfaced irregular shape and rough-surfaced spheres, respectively. Magnesium aluminosilicate generated a sticky powder, due to its relatively low specific surface area, resulting in insufficient adsorption of PLAG. These solid SEDDSs improved the solubility, dissolution and oral bioavailability of PLAG. Ultimately, the solid SEDDS prepared with silicon dioxide resulted in the best drug loading efficiency, shape, solubility, dissolution and oral bioavailability due to its great specific surface area. Therefore, mesoporous carriers with different specific surface areas markedly influenced the physicochemical properties, solubility, dissolution and oral bioavailability of PLAG-loaded solid SEDDS.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The effect of mesoporous carriers on PLGA-loaded solid SEDDS were assessed. </LI> <LI> Numerous PLGA-loaded solid SNEDDS were prepared using spray drying technique. </LI> <LI> Calcium silicate, silicon dioxide and magnesium aluminosilicate were used as the mesoporous carriers. </LI> <LI> The solid SEDDS prepared with silicon dioxide gave most excellent loading efficiency and bioavailability. </LI> <LI> Mesoporous carriers markedly influenced the physicochemical properties and bioavailability of solid SEDDS. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

cAMP induction by ouabain promotes endothelin-1 secretion via MAPK/ERK signaling in beating rabbit atria

Li-qun Peng,Ping Li,Qiu-li Zhang,Lan Hong,Li-ping Liu,Xun Cui,Bai-ri Cui 대한생리학회-대한약리학회 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.1

Adenosine 3 ,5 -cyclic monophosphate (cAMP) participates in the regulation of numerous cellular functions, including the Na⁺-K⁺-ATPase (sodium pump). Ouabain, used in the treatment of several heart diseases, is known to increase cAMP levels but its effects on the atrium are not understood. The aim of the present study was to examine the effect of ouabain on the regulation of atrial cAMP production and its roles in atrial endothelin-1 (ET-1) secretion in isolated perfused beating rabbit atria. Our results showed that ouabain (3.0 μmol/L) significantly increased atrial dynamics and cAMP levels during recovery period. The ouabainincreased atrial dynamics was blocked by KB-R7943 (3.0 μmol/L), an inhibitor for reverse mode of Na⁺-Ca²⁺ exchangers (NCX), but did not by L-type Ca²⁺ channel blocker nifedipine (1.0 μmol/L) or protein kinase A (PKA) selective inhibitor H-89 (3.0 μmol/L). Ouabain also enhanced atrial intracellular cAMP production in response to forskolin and theophyline (100.0 μmol/L), an inhibitor of phosphodiesterase, potentiated the ouabain-induced increase in cAMP. Ouabain and 8-Bromo-cAMP (0.5 μmol/L) markedly increased atrial ET-1 secretion, which was blocked by H-89 and by PD98059 (30 μmol/L), an inhibitor of extracellular-signal-regulated kinase (ERK) without changing ouabain-induced atrial dynamics. Our results demonstrated that ouabain increases atrial cAMP levels and promotes atrial ET-1 secretion via the mitogen-activated protein kinase (MAPK)/ERK signaling pathway. These findings may explain the development of cardiac hypertrophy in response to digitalis-like compounds.

cAMP induction by ouabain promotes endothelin-1 secretion via MAPK/ERK signaling in beating rabbit atria

Peng, Li-qun,Li, Ping,Zhang, Qiu-li,Hong, Lan,Liu, Li-ping,Cui, Xun,Cui, Bai-ri The Korean Society of Pharmacology 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.1

Adenosine 3',5'-cyclic monophosphate (cAMP) participates in the regulation of numerous cellular functions, including the $Na^+-K^+$-ATPase (sodium pump). Ouabain, used in the treatment of several heart diseases, is known to increase cAMP levels but its effects on the atrium are not understood. The aim of the present study was to examine the effect of ouabain on the regulation of atrial cAMP production and its roles in atrial endothelin-1 (ET-1) secretion in isolated perfused beating rabbit atria. Our results showed that ouabain ($3.0{\mu}mol/L$) significantly increased atrial dynamics and cAMP levels during recovery period. The ouabain-increased atrial dynamics was blocked by KB-R7943 ($3.0{\mu}mol/L$), an inhibitor for reverse mode of $Na^+-Ca^{2+}$ exchangers (NCX), but did not by L-type $Ca^{2+}$ channel blocker nifedipine ($1.0{\mu}mol/L$) or protein kinase A (PKA) selective inhibitor H-89 ($3.0{\mu}mol/L$). Ouabain also enhanced atrial intracellular cAMP production in response to forskolin and theophyline ($100.0{\mu}mol/L$), an inhibitor of phosphodiesterase, potentiated the ouabain-induced increase in cAMP. Ouabain and 8-Bromo-cAMP ($0.5{\mu}mol/L$) markedly increased atrial ET-1 secretion, which was blocked by H-89 and by PD98059 ($30{\mu}mol/L$), an inhibitor of extracellular-signal-regulated kinase (ERK) without changing ouabain-induced atrial dynamics. Our results demonstrated that ouabain increases atrial cAMP levels and promotes atrial ET-1 secretion via the mitogen-activated protein kinase (MAPK)/ERK signaling pathway. These findings may explain the development of cardiac hypertrophy in response to digitalis-like compounds.

Comparisons of Curative and Side Effects of Chemoradiotherapy among Xinjiang Han, Uigur and Kazakh Esophageal Carcinoma Patients

Zhang, Li,Ma, Li-Li,Zhang, Jian-Qing,Yang, Mei,Xun, Tu-Er,Li, Ai Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Objective: This study aimed to explore the differences in the curative and side effects of chemoradiotherapy on esophageal cancer (EC) among Xinjiang Han, Uigur and Kazakh patients. Methods: 170 patients with IIA stage-IV of esophageal squamous cell carcinoma were analyzed retrospectively. Based on different nationalities, they were divided into the Han, Uigur and Kazakh groups. The 1-, 2- and 3-year survival rates, incidence of the side effects (including hematological toxicities, radioactive esophagitis and percutaneous reactions) and application of antibiotics and harmonics were compared among the groups. There was no significant difference in the short-term curative effects among the Han, Uigur and Kazakh groups. The 1- 2- and 3-year survival rates of the three groups were 84%, 40%, 26%; 78%, 27%, 18%; and 60%, 21%, 12% ($x^2$=14.497, P<0.05). The incidence rate of hamatological toxicity ${\geq}$Grade 2 in the Kazakh group was significantly lower than that in the Han or Uigur group. Results: The incidence rates of radioactive esophagitis and percutaneous reactions Grade 2 in the Han group were significantly higher than those in the Uigur or Kazakh group. There was no significant difference in the types of applied antibiotics among the groups, but there were significant differences in the days of antibiotic application and proportion of patients receiving harmonics between the Hans and either of other groups. Conclusion: Chemoradiotherapy shows a better effect in the long-term survival rate among Han EC patients compared with Uigur or Kazakh EC patients. Uigur and Kazakh patients show a better tolerance to the side effects of chemoradiotherapy compared with Hans.

Survival of Cancer Patients in Northeast China: Analysis of Sampled Cancers from Population-Based Cancer Registries

Yanxia Li,Liya Yu,Jun Na,Shuang Li,Li Liu,Huijuan Mu,Xuanjuan Bi,Xiaoxia An,Xun Li,Wen Dong,Guowei Pan 대한암학회 2017 Cancer Research and Treatment Vol.49 No.4

Purpose The cancer survival was characterized by following up sampled subgroups of cancer cases from three population-based cancer registries in Northeast China. Materials and Methods Survival analysis was used to analyze 6,871 patients, who had one of the 21 most common cancers based on sampling from the population-based cancer registries of three cities in Liaoning Province. All patients were diagnosed between 2000 and 2002 and were followed up to the end of 2007 by active and passive methods. The 5-year age standardized relative survival rates (ASRS) were estimated for all cancers combined and each of the 21 individual cancers. Results The survival status was traced for 80.8% of 8,506 sampled cancer cases. The 5-year ASRS for all 21 cancers combined was 41.5% (95% confidence interval, 40.3 to 42.7), the highest ASRS was observed for thyroid cancer (85.2%), breast cancer (78.9%), uterine corpus cancer (75.9%), and urinary bladder cancer (70.2%); the lowest 5-year ASRS was noted in pancreatic cancer (8.8%), liver cancer (11.0%), esophageal cancer (18.8), and lung cancer (19.6%). The cancer survival rates in Liaoning cities were similar to those of urban areas in mainland China, but significantly lower than those in Hong Kong, Korea, and Japan. Conclusion The strikingly poor cancer survival rates in three cities of Liaoning Province and in other places in China highlight the need for urgent investment in cancer prevention, early detection, and standardized and centralized treatment.

Learning New Knowledge without influencing the Old in Expert Systems Based on Neural Network

Xun Liang,Ji Hong Du,Shawei Xia,Li Li 대한전자공학회 1994 ICONIP : International Conference On Neural Inform Vol.3 No.3

차분 선부호화 구조를 적용한 LTE-A 상향링크 시스템의 성능 분석

Xun Li,박노윤(Noe Yoon Park),김영주(Young Ju Kim) 大韓電子工學會 2012 電子工學會論文誌-TC (Telecommunications) Vol.49 No.5

LTE 시스템에서는 폐회로 기반의 다중 안테나 기술이 적용되었으며, 차분 코드북을 비롯한 다양한 다중 안테나 기반의 선부호화 기술들이 향상된 LTE (LTE-Advanced) 시스템의 요구조건을 만족시키기 위해 제안되었다. 차분 코드북 설계와 관련하여 이전에 연구된 내용은 준 대각(quasi-diagonal) 단위 행렬 및 구면 캡(spherical cap)에 중점을 두었지만, 이는 동 이득 성질을 만족하지 못한다. 동 이득 성질은 특히 상향 링크에서 첨두 전력 대 평균 전력비 (PAPR)에 상당한 영향을 미치므로 매우 중요하다. 본 논문에서는 각 송신 안테나에 동 이득을 유지하는 성질을 이용한 새로운 차분 코드북을 상향 링크 기반 차분 선부호화 시스템에 적용하고, 이를 통해 비트 오류율(BER)과 첨두 전력 대 평균 전력비를 분석하였다. 특히, 송신기의 비선형 증폭기를 고려하여 다양한 차분 선부호화 기법들의 성능을 분석하였다. 모의 실험을 통해 선형 증폭기를 고려할 경우 기존에 제안된 차분 코드북이 우수한 성능을 보이지만, 비선형 증폭기를 고려할 경우에는 제안하는 차분 코드북의 우수함을 증명하였다. The closed-loop multiple-input multiple-output (MIMO) system has been adopted by long term evolution (LTE) system. Many techniques are proposed to enhance the transmission of LTE's advanced version to meet the increasing requirement, in which differential codebook gains a lot of interest. Previous researches on designing differential codebooks focused on quasi-diagonal unitary matrix which cannot guarantee the equal gain property. The equal gain property is very important to uplink because the performance of uplink is very sensitive to the peak-to-average power ratio (PAPR). In this paper, we derive the analytical expression of average bit error rate and PAPR for differential precoding MIMO system. Using the analytical results, we investigate the performances of several differential precoding schemes considering non-linear amplifier at the transmitter. Some selected simulation results indicate that the conventional differential precoding schemes have good performances without the consideration of non-linear amplifier. While considering non-linear amplifier, the proposed differential codebook outperforms other differential precoding schemes because it maintains the equal gain per transmit antenna.

Differential Precoding Algorithm for Noisy Feedback Channels

Xun Li(이신),Park Noe Yoon(박노윤),Kim Young Ju(김영주) 한국통신학회 2012 한국통신학회 학술대회논문집 Vol.2012 No.2

Learning New Knowledge without influencing the Old in Expert Systems Based on Neural Network

Xun Liang,Ji Hong Du,Shawei Xia,Li Li 대한전자공학회 1994 ICONIP : International Conference On Neural Inform Vol.3 No.2

A (n, t, n) Verifiable Multi-secret Sharing Scheme with Secure Secret Reconstruction

Li Meng,Qu Shaoyun,Xun Tiantian,Yu Jia 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.1