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71.
Galactose-modified cationic liposomes as a liver-targeting delivery system for small interfering RNA
Sonoke S Ueda T Fujiwara K Kuwabara K Yano J 《Biological & pharmaceutical bulletin》2011,34(8):1338-1342
We have developed a galactose-modified cationic liposome for delivery of small interfering RNA (siRNA) to the liver. The liposomes were designed to be transported into hepatocytes via the asialoglycoprotein receptor, which recognizes galactose residues. The liposomes contained a novel galactose-modified lipid, 1,2-dioleoyl-sn-glycerol-3-phosphatidyl-N-(1-deoxylactito-1-yl)ethanolamine (GDOPE). Delivery of siRNA to hepatocytes by the liposomes was evaluated by measuring the gene-silencing activity of liposome : siRNA complexes in two human hepatoma cell lines. A formulation with a cationic lipid : GDOPE ratio of 3 : 5 by weight, LIC-G5, showed the strongest activity. In mice, intravenous injection of LIC-G5 complexed with (3)H-labeled siRNA led to accumulation of radioactivity in the liver. When the hepatic cellular uptake was determined after intravenous injection into mice followed by collagenase liver perfusion, the distribution of siRNA to parenchymal cells was 1.9 times higher when LIC-G5 rather than nongalactosylated LIC was used as the carrier. The concentration of siRNA accumulated was 45 μg/ml, 30 times the concentration that produced strong gene silencing in vitro and therefore presumably sufficient for a therapeutic effect. Because increasing the cationic-lipid content of a liposome carrier generally enhances the uptake of siRNA by the liver at the expense of increased cell toxicity, we used only a moderate amount of cationic lipid in our galactose-modified carrier. LIC-G5 enhanced the uptake of siRNA by the liver without cytotoxic effects and is a promising candidate delivery system for liver-targeted siRNA therapy. 相似文献
72.
Lee KM Manning V Teoh HC Winslow M Lee A Subramaniam M Guo S Wong KE 《Drug and alcohol review》2011,30(4):441-447
Introductions and Aims. Research from western countries indicates that family members of addiction patients report heightened stress and psychological morbidity. This current study aimed to examine stress, coping behaviours, related morbidity and subsequent resource utilisation among family members of patients attending a national treatment program in Singapore. Design and Methods. The study used a matched case–control design. One hundred family members of addiction patients attending treatment and 100 matched controls completed a semi‐structured interview with a researcher. This included the Beck Depression Inventory‐II, Short‐Form Health Survey‐36, General Health Questionnaire‐28, Perceived Stress Scale, Family Member Impact Scale and Coping Questionnaire, and also assessed service utilisation. Results. T‐tests revealed significantly greater depression, stress and psychiatric morbidity and poorer overall well‐being (Short‐Form Health Survey‐36) among family members compared with controls. Despite the apparent negative impact on mental health, their physical morbidity did not differ from controls and services utilisation was low. Tolerant‐inactive coping was found to be most strongly correlated with psychological well‐being. Multivariate analysis indicated that perceived stress was the strongest predictor of overall strain (General Health Questionnaire), but this was not moderated by coping style. Discussion and Conclusions. Subjective appraisal of stress and coping responses are essential factors affecting the morbidity of family members. Family members demonstrated a need and willingness to engage in formal treatment/counselling for their own problems that were attributed to living with an addiction patient. This provides an opportunity for stress management and brief interventions to modify coping styles, thereby minimizing the potential negative mental health impact on family members.[Lee KMT, Manning V, Teoh HC, Winslow M, Lee A, Subramaniam M, Guo S, Wong KE. Stress‐coping morbidity among family members of addiction patients in Singapore. Drug Alcohol Rev 2011;30:441–447] 相似文献
73.
Yun H Lee HJ Jang JH Kim JS Lee SH Kim JW Park SJ Park YM Hwang SG Rim KS Kang SK Lee HS Jeong SH 《Journal of medical virology》2011,83(12):2073-2081
Korea has recently experienced a nationwide outbreak of hepatitis A. This study aimed to investigate hepatitis A virus (HAV) genotypes and to compare clinical features between patients infected with HAV genotype IA and those with genotype IIIA. From September 2006 to August 2008, 595 patients with symptomatic hepatitis A were enrolled prospectively in four hospitals in Korea. Among them, 556 patients participated in this study by providing serum or stool samples for genotypic analysis. HAV RNA was detected in 499 patients (89.7%). Major genotypes included IA (n = 244, 48.9%) and IIIA (n = 244, 48.9%), and the remaining genotype was IB (n = 11, 2.2%). From September 2006 to August 2007, the distribution of genotypes IA and IIIA were 64.6% and 35.6%, respectively, which changed to 42.3% and 54.6%, respectively, from September 2007 to August 2008, indicating change of circulating HAV genotypes in the study period from IA to IIIA. Major patterns of amino acid substitution in the VP3/VP1 junction region were observed at position 512 (P → L) in genotype IA and at 520 (R → K) in genotype IIIA. Patients with genotype IIIA infection showed significantly higher aminotransferase levels, prothrombin time, and leukocyte count, with more severe symptoms than those with genotype IA at the time of admission. These results suggest the occurrence of a change of circulating HAV genotypes in recent community‐wide outbreaks of hepatitis A in Korea, and genotype IIIA infection, compared with genotype IA infection, might show more severe clinical manifestations. J. Med. Virol. 83:2073–2081, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
74.
Takagi K Kawaguchi Y Kawamoto M Ota Y Tochimoto A Gono T Katsumata Y Takagi M Hara M Yamanaka H 《Journal of autoimmunity》2011,36(3-4):181-188
Systemic sclerosis (SSc) is a chronic disease of unknown etiology that is characterized by multiple tissue fibrosis. Transforming Growth Factor-beta (TGF-β) is thought to be the most important mediator that induces fibrosis. However, the molecular mechanisms by which fibrosis is induced have not been fully elucidated. In this study, the role of activin, a member of the TGF-β superfamily, was investigated in the pathogenesis of fibrosis in SSc. Serum activin A levels in patients with SSc were measured by ELISA, and the expression of the activin receptor type IB (ACVRIB/ALK4) and the activity of the signaling pathway via ACVRIB/ALK4 were investigated using western blotting. To evaluate a potential therapeutic strategy for SSc, we also attenuated the ACVRIB/ALK4 pathway using an inhibitor. Serum activin A levels were significantly higher in SSc patients than in normal controls. Activin A and ACVRIB/ALK4 expression were also higher in cultured SSc fibroblasts. Activin A stimulation induced phosphorylation of Smad2/3 and CTGF expression in SSc fibroblasts. Procollagen production and Col1α mRNA also increased upon stimulation by activin A. The basal level of Smad2/3 phosphorylation was higher in cultured SSc fibroblasts than in control cells, and treatment with the ALK4/5 inhibitor SB431542 prevented phosphorylation of Smad2/3 and CTGF expression. Furthermore, production of collagen was also induced by activin A. Activin A-ACVRIB/ALK4-Smad-dependent collagen production was augmented in SSc fibroblasts, suggesting the involvement of this signaling mechanism in SSc. Inhibition of the activin A-ACVRIB/ALK4-Smad pathway would be a new approach for the treatment of SSc. 相似文献
75.
76.
77.
AbouZahr C Cleland J Coullare F Macfarlane SB Notzon FC Setel P Szreter S;Monitoring of Vital Events 《Lancet》2007,370(9601):1791-1799
Good public-health decisionmaking is dependent on reliable and timely statistics on births and deaths (including the medical causes of death). All high-income countries, without exception, have national civil registration systems that record these events and generate regular, frequent, and timely vital statistics. By contrast, these statistics are not available in many low-income and lower-middle-income countries, even though it is in such settings that premature mortality is most severe and the need for robust evidence to back decisionmaking most critical. Civil registration also has a range of benefits for individuals in terms of legal status, and the protection of economic, social, and human rights. However, over the past 30 years, the global health and development community has failed to provide the needed technical and financial support to countries to develop civil registration systems. There is no single blueprint for establishing and maintaining such systems and ensuring the availability of sound vital statistics. Each country faces a different set of challenges, and strategies must be tailored accordingly. There are steps that can be taken, however, and we propose an approach that couples the application of methods to generate better vital statistics in the short term with capacity-building for comprehensive civil registration systems in the long run. 相似文献
78.
79.
Characteristics of patients with early systemic sclerosis and severe gastrointestinal tract involvement 总被引:1,自引:0,他引:1
Nishimagi E Tochimoto A Kawaguchi Y Satoh T Kuwana M Takagi K Ichida H Kanno T Soejima M Baba S Kamatani N Hara M 《The Journal of rheumatology》2007,34(10):2050-2055
OBJECTIVE:To clarify the clinical features of patients with systemic sclerosis (SSc) who developed severe gastrointestinal tract (GIT) involvement in the early stage of the disease. METHODS: Three hundred two consecutive Japanese patients with SSc were investigated: Group 1 comprised 14 patients with severe GIT involvement (malabsorption syndrome and/or pseudo-obstruction) within 2 years of onset of SSc; group 2 consisted of all patients without severe GIT involvement (n = 288); and group 3 consisted of 117 patients without severe GIT involvement within 2 years of onset of SSc. Autoantibodies were evaluated using double immunodiffusion, ELISA, and immunoprecipitation. RESULTS: We found significant differences in clinical features among the 3 groups. Diffuse cutaneous type, erosive esophagitis, and myositis were more common in group 1 than in group 2 (p = 0.007, 0.003, and 0.003, respectively) or group 3 (p = 0.04, 0.002, and 0.01, respectively), whereas interstitial lung disease (ILD) was more frequent in group 2 (p = 0.005) and group 3 (p = 0.02) versus group 1. Antinuclear antibodies showed a nucleolar pattern significantly more frequently in group 1. Myositis-related autoantibodies, including anti-U1RNP, anti-U3RNP, anti-Ku, and anti-signal recognition particle antibodies, were observed in 57% of group 1. CONCLUSION: Our findings strongly suggest the existence of a subgroup of SSc patients with severe GIT involvement in the early stage. Among the Japanese individuals, these patients never developed severe ILD, even though they were classified as having diffuse cutaneous SSc. 相似文献
80.
Park JK Lee SH Yoon WJ Lee JK Park SC Park BJ Jung YJ Kim BG Yoon JH Kim CY Ha J Park KJ Kim YJ 《Journal of gastroenterology and hepatology》2007,22(3):377-382
BACKGROUND AND AIM: Abdominal wall hernia is a common feature of decompensated liver cirrhosis and frequently causes life-threatening complications or severe pain. However, there have been no data reported on postoperative mortality, hepatic functional deterioration and recurrence rate according to Child-Turcotte-Pugh (CTP) class and to the presence of refractory ascites. METHODS: The study population comprised 53 liver cirrhosis patients who underwent hernia repair operation. Comparisons were made of 30-day mortality among the different CTP classes, and between those with or without refractory ascites. Liver function was also analyzed just before the operation, in the immediate postoperative period, and in the remote postoperative period. RESULTS: Seventeen patients were in CTP class A, 27 patients in class B, and 9 patients in class C. The median follow-up duration was 24 months. There was single 30-day postoperative mortality in class C, and no CTP class deterioration after 30 days of operation. There was no mortality or recurrences in 17 patients with medically refractory ascites. The difference in 30-day mortality according to CTP class and the presence of refractory ascites did not show statistical significance (P = 0.17 and 0.97, respectively). CONCLUSION: Hernia operation could be done safely in CTP class A and B with low rate of recurrences, and there was no definitive increase in the operative risk in class C. In addition, refractory ascites did not increase operative risk and recurrence rate. Therefore, surgical repair might be recommended even in patients with refractory ascites and poor hepatic function to prevent life-threatening complications or severe pain. 相似文献