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21.
AB-type amphiphilic copolymers (abbreviated as LE) composed of poly (L-leucine) (PLL) as the A component and poly (ethylene
oxide) (PEO) as the B component were synthesized by the ring-opening polymerization of L-leucine N-carboxy-anhydride initiated
by methoxy polyoxyethylene amine (Me-PEO-NH2) and characterized. Core-shell type nanoparticles were prepared by the diafiltration method. Particle size distribution obtained
by dynamic light scattering was dependent on PLL composition and the size for LE-1, LE-2 and LE-3 was 369.6±267, 523.4±410
and 561.2±364 nm, respectively. Shapes of the nanoparticles observed by transmission electron microscope (TEM) were almostly
spherical. The critical micelle concentration (CMC) of the nanoparticles determined by a fluorescence probe technique was
dependent on the composition of hydrophobic PLL, and the CMC for LE-1, LE-2 and LE-3 was 2. 0×10−6, 1.7×10−6 and 1.5×10−6 (mol/l), respectively. Clonazepam release from core-shell type nanoparticles in vitro was dependent on PLL composition and
drug loading content. 相似文献
22.
As shown earlier p-XSC inhibits DMBA-induced mammary cancer in female CD rats. This inhibition is due, in part, to inhibition of DMBA-DNA adduct formation in the target organ. We have now utilized the DMBA-DNA binding assay to evaluate the chemopreventive potential of positional isomers of XSC (o-, m- and p-XSC) applied at selenium doses of 5 and 15 ppm; p-XTC, the sulfur analog of p-XSC, was used at an equimolar dose to determine whether selenium is required for the observed inhibitory effect. Selenium and sulfur compounds were administered in a semipurified high-fat diet (23.5% corn oil). Rats were fed for 1 week prior to oral administration of a single dose of [H-3]DMBA (5 mg/rat); animals were sacrificed 24 h later, DNA was isolated from mammary fat pads and levels of total binding were determined. All agents produced a dose-dependent inhibition of DMBA-DNA binding in the mammary tissues. The inhibition at 5, respectively 15 ppm Se in the form of XSC isomers and at 30 mu M, respectively 90 mu M in the form of p-XTC was: o-XSC (27%, 42%); m-XSC (32%, 47%); p-XSC (22%, 29%); and p-XTC (10%, 20%); only inhibition by dietary o-XSC and m-XSC at 15 ppm Se reached statistical significance (p<0.05). Thus, o-XSC and m-XSC equally inhibit DMBA-DNA binding and both are better inhibitors than p-XSC; the latter appears to be slightly more effective than its sulfur analog p-XTC. Clearly, the structure of the selenium-containing compound is a critical factor in determining the extent of inhibition of DMBA-DNA binding. The described short-term in vivo assay may constitute the basis for future selection of chemopreventive agents in the rat mammary tumor model system. 相似文献
23.
Yamazaki Hiroshi; Mimura Mayumi; Oda Yoshimitsu; Gonzalez Frank J.; El-Bayoumy Karam; Chae Young-Heum; Guengerich F.Peter; Shimada Tsutomu 《Carcinogenesis》1994,15(3):465-470
In order to address the hypothesis that 6-aminochrysene (6-AC)is converted to genotoxic products by cytochrome P450 enzymesvia two activation pathways (N-hydroxylation and epoxidation),the activation of 6-AC and trans-l,2-dihydro-l,2-dihydroxy-6-aminochrysene(6-AC-diol) to genotoxic metabolites was examined in rat andhuman liver microsomal cytochrome P450 enzymes using Salmonellatyphimurium TA1535/pSK1002 and TA1535/pSK1002/pNM12 (NM2009)as tester strains. The latter bacteria, an O-acetyl-transferase-overexpressingstrain, was highly sensitive to metabolites derived from activationof 6-AC, but not those from 6-AC-diol, using liver microsomesfrom phenobarbital-treated rats or a reconstituted monooxygenasesystem containing P4502B1 or -2B2, thus suggesting the rolesof P450 and acetyltransferase systems in the activation process.6-AC-diol, on the other hand, was activated very efficientlyby liver microsomes prepared from ß-naphthoflavone-treatedrats or a reconstituted system containing P4501A1 or -1A2; theactivation reaction is considered to proceed through diol-epoxideformation. The contribution of rat P4501A enzymes towards activationof 6-AC-diol was confirmed by the inhibitory effects on theactivation process of -naphthoflavone, a specific inhibitorof P4501 A-related activities, and antibodies raised againstpurified P4501A1 and -1A2. In humans, P4501A2 was found to bethe major enzyme involved in the activation of 6-AC-diol togenotoxic metabolites while the parent compound 6-AC was activatedmainly by P4503A4. Experiments using recombinant P450 proteinsexpressed in human lymphoblastoid cells lines showed that humanP4501A1 could also activate 6-AC-diol to reactive metabolitesat almost the same rate measured with P4501A2. In addition,P4502B6 was found to efficiently catalyze the activation of6-AC to genotoxic metabolites, and P4503A4 was active in theactivation of 6-AC-diol as well as 6-AC. Addition of purifiedrat epoxide hydrolase to the incubation mixture containing purifiedrat P4501A1 or microsomes expressing human P4501A1 caused inhibitionof activation of 6-AC-diol. These results suggest the existenceof different enzymatic activation pathways for 6-AC and 6-AC-diol.The former carcinogen may be N-hydroxylated principally by P4502Benzymes in rats and P4503A4 and -2B6 in humans and activationto its ultimate metabolites may proceed through esterificationof the N-hydroxy metabolites by an N-acetyltransferase. The6-AC-diol is metabolized to its ultimate diolepoxide productby P4501A enzymes in rat and human liver microsomes. P4503A4(humans) and P4503A2 (rats) may also contribute to some extentin the activation of 6-AC-diol, albeit at lower rates than thoseof P4501A enzymes. 相似文献
24.
Yoon KH Ha HK Kim CG Roh BS Yun KJ Chae KM Lim JH Auh YH 《AJR. American journal of roentgenology》2000,175(4):1135-1139
OBJECTIVE. We describe the CT and pathologic features of malignant papillary neoplasms of the intrahepatic bile ducts in 15 patients. CONCLUSION. CT is a useful technique for revealing intraductal lesions, although the findings are nonspecific and variable. When intraductal masses or nodules are seen with localized dilatation of the intrahepatic bile ducts on CT scans, malignant papillary neoplasms of the intrahepatic bile ducts should be included in the differential diagnosis. 相似文献
25.
Inhibitory action of water soluble fraction of Terminalia chebula on systemic and local anaphylaxis 总被引:3,自引:0,他引:3
Shin TY Jeong HJ Kim DK Kim SH Lee JK Kim DK Chae BS Kim JH Kang HW Lee CM Lee KC Park ST Lee EJ Lim JP Kim HM Lee YM 《Journal of ethnopharmacology》2001,74(2):133-140
We investigated the effects of the water soluble fraction of Terminalia chebula (Combretaceae) (WFTC) on systemic and local anaphylaxis. WFTC administered 1h before compound 48/80 injection inhibited compound 48/80-induced anaphylactic shock 100% with doses of 0.01-1.0 g/kg. When WFTC was administered 5 or 10 min after compound 48/80 injection, the mortality also decreased in a dose-dependent manner. Passive cutaneous anaphylaxis was inhibited by 63.5+/-7.8% by oral administration of WFTC (1.0 g/kg). When WFTC was pretreated at concentrations ranging from 0.005 to 1.0 g/kg, the serum histamine levels were reduced in a dose-dependent manner. WFTC (0.01-1.0 mg/ml) also significantly inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. However, WFTC (1.0 mg/ml) had a significant increasing effect on anti-dinitrophenyl IgE-induced tumor necrosis factor-alpha production from RPMC. These results indicate that WFTC may possess a strong antianaphylactic action. 相似文献
26.
Weon Cheol Lim Jitendra Pal Singh Jonghan Song Tae-Yeon Seong Keun Hwa Chae 《RSC advances》2022,12(46):29666
Herein, we systematically studied the effect of various excitation processes on the structural, optical, and magnetic properties of ZnO films implanted with 80 keV Ar+, 110 keV Mn+, and 190 keV Ag+ ions. Four different doses of 1 × 1013, 1 × 1014, 1 × 1015, and 2 × 1016 ions per cm2 were used for implantation. It was observed that the structural, optical, and magnetic properties of the implanted samples were dominantly affected at the highest dose of 2 × 1016 ions per cm2. For lower doses, insignificant changes in these properties were observed. A comparison of various processes involved in the implantation process shows that both the electronic excitation and nuclear excitation processes are responsible for the changes in the structural, optical, and magnetic properties of the implanted ZnO films.Dominant changes in structural, optical, and magnetic properties were observed at the highest dose of implanted ions with larger ionic radii which is due to the large number of produced defects in the host. 相似文献
27.
Ui Joung Youn Nighat Fatima Quan Cheng Chen Sungwook Chae Tran Manh Hung Byung‐Sun Min 《Phytotherapy research : PTR》2013,27(9):1419-1422
Two neolignans, 4′‐methoxymagndialdehyde (1) and magnaldehyde B (2), were isolated from the stem bark of Magnolia officinalis (Magnoliaceae), evaluated for apoptosis‐inducing effects in human cervical epitheloid carcinoma HeLa cells. The apoptosis‐inducing activity of compounds 1 and 2 were assessed by DNA content using flow cytometric analysis. In the immunoblotting analysis, the treatment with 1 and 2 resulted in the cleavage of procaspase‐8 and ‐3 and poly(ADP‐ribose)polymerase into active forms. In addition, in vivo, the administration of 2 to Lewis lung carcinoma‐inoculated mice evidenced a significant inhibition of tumor growth (volume) with reduction of 28.7% at concentration of 20 mg/kg, as compared with the control mice. These findings suggest that 2 can inhibit the proliferation of tumor cells, and might be an anti‐tumoric agent. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
28.
Hyeonseong Woo Sanghee Lee Hyun Sung Lee Hyun Jun Chae Jongtak Jung Myung Jin Song Sung Yoon Lim Yeon Joo Lee Young-Jae Cho Eu Suk Kim Hong Bin Kim Jae-Young Lim Kyoung-Ho Song Jaewon Beom 《Journal of Korean medical science》2022,37(34)
BackgroundThis study aimed to investigate the effects of comprehensive rehabilitation management on functional recovery and examine the correlation between clinical parameters and improvements in functional outcomes in severe-to-critical inpatients with coronavirus disease 2019 (COVID-19) in a tertiary hospital.MethodsPost-acute COVID-19 patients who had a World Health Organization (WHO) ordinal scale of 5–7, underwent intensive care, and received comprehensive rehabilitation management, including exercise programs, nutritional support, dysphagia evaluation, and psychological care were included. The appendicular skeletal muscle mass index (SMI), Medical Research Council sum score, handgrip strength, number of repetitions in the 1-minute sit-to-stand test, gait speed, Berg Balance Scale (BBS), and Functional Ambulation Classification (FAC) were evaluated at hospital stay, discharge, and 1-month follow-up. The correlation between the rehabilitation dose and improvement in each outcome measure was analyzed.ResultsOverall, 37 patients were enrolled, of whom 59.5% and 32.4% had a score of 6 and 7 on the WHO ordinal scale, respectively. Lengths of stay in the intensive care unit and hospital were 33.6 ± 23.9 and 63.8 ± 36.5 days. Outcome measures revealed significant improvements at discharge and 1-month follow-up. The SMI was significantly increased at the 1-month follow-up (6.13 [5.24–7.76]) compared with that during the hospital stay (5.80 [5.39–7.05]). We identified dose-response associations between the rehabilitation dose and FAC (ρ = 0.46) and BBS (ρ = 0.50) scores. Patients with older age, longer hospitalization, longer stay at the intensive care unit, longer duration of mechanical ventilation, tracheostomy, a more depressive mood, and poorer nutritional status revealed poorer improvement in gait speed at the 1-month follow-up.ConclusionComprehensive rehabilitation management effectively improved muscle mass, muscle strength, and physical performance in severe-to-critical COVID-19 patients. Dose-response relationship of rehabilitation and functional improvement emphasizes the importance of intensive post-acute inpatient rehabilitation in COVID-19 survivors.Trial RegistrationClinicalTrials.gov Identifier: NCT05104411相似文献
29.
Joo Myung Lee Hyun Sung Joh Ki Hong Choi David Hong Taek Kyu Park Jeong Hoon Yang Young Bin Song Jin-Ho Choi Seung-Hyuk Choi Jin-Ok Jeong Jong-Young Lee Young Jin Choi Jei-Keon Chae Seung-Ho Hur Jang-Whan Bae Ju-Hyeon Oh Kook-Jin Chun Hyun-Joong Kim Byung Ryul Cho Doosup Shin Seung Hun Lee Doyeon Hwang Hyun-Jong Lee Ho-Jun Jang Hyun Kuk Kim Sang Jin Ha Eun-Seok Shin Joon-Hyung Doh Joo-Yong Hahn Hyeon-Cheol Gwon 《Journal of Korean medical science》2023,38(5)
BackgroundThe risk of device thrombosis and device-oriented clinical outcomes with bioresorbable vascular scaffold (BVS) was reported to be significantly higher than with contemporary drug-eluting stents (DESs). However, optimal device implantation may improve clinical outcomes in patients receiving BVS. The current study evaluated mid-term safety and efficacy of Absorb BVS with meticulous device optimization under intravascular imaging guidance.MethodsThe SMART-REWARD and PERSPECTIVE-PCI registries in Korea prospectively enrolled 390 patients with BVS and 675 patients with DES, respectively. The primary endpoint was target vessel failure (TVF) at 2 years and the secondary major endpoint was patient-oriented composite outcome (POCO) at 2 years.ResultsPatient-level pooled analysis evaluated 1,003 patients (377 patients with BVS and 626 patients with DES). Mean scaffold diameter per lesion was 3.24 ± 0.30 mm in BVS group. Most BVSs were implanted with pre-dilatation (90.9%), intravascular imaging guidance (74.9%), and post-dilatation (73.1%) at proximal to mid segment (81.9%) in target vessel. Patients treated with BVS showed comparable risks of 2-year TVF (2.9% vs. 3.7%, adjusted hazard ratio [HR], 1.283, 95% confidence interval [CI], 0.487–3.378, P = 0.615) and 2-year POCO (4.5% vs. 5.9%, adjusted HR, 1.413, 95% CI, 0.663–3.012, P = 0.370) than those with DES. The rate of 2-year definite or probable device thrombosis (0.3% vs. 0.5%, P = 0.424) was also similar. The sensitivity analyses consistently showed comparable risk of TVF and POCO between the 2 groups.ConclusionWith meticulous device optimization under imaging guidance and avoidance of implantation in small vessels, BVS showed comparable risks of 2-year TVF and device thrombosis with DES.Trial RegistrationClinicalTrials.gov Identifier: , NCT02601404 NCT04265443相似文献
30.
BackgroundA cervical transforaminal epidural (TFE) steroid injection is a useful treatment option for cervical radicular pain, but it carries a small risk of catastrophic complications. Several studies have reported that cervical facet joint (FJ) steroid injection can reduce cervical radicular pain through an indirect epidural spread. The aim of this retrospective comparative study was to evaluate the pain scores and functional disability in subjects receiving cervical FJ or TFE steroid injection for the treatment of cervical radicular pain due to foraminal stenosis (FS).MethodsWe selected 278 patients 18 years of age and older who underwent cervical FJ (n = 130) or TFE (n= 148) steroid injection for cervical radicular pain. The primary outcomes included pain scores and functional disability during hospital visits one, three, and six months after the initial injection. Secondary outcomes were the proportion of responders and Medication Quantification Scale (MQS) scores. Adverse events and variables correlating with effectiveness one month after the initial injection were also evaluated.ResultsThe Numeric Rating Scale and Neck Disability Index scores showed a significant improvement one, three, and six months after the initial injection in both groups, with no significant differences between the groups. No significant differences were observed in the success rates of the procedure one, three, and six months after the initial injection for either group. There were no significant differences in MQS between the groups during the follow-up period. Univariate and multivariate logistic regression analyses revealed that the injection method, age, sex, number of injections, FS severity, MQS, pain duration, and the presence of cervical disc herniation were not independent predictors of treatment success.ConclusionThe efficacy of FJ steroid injection may not be inferior to that of TFE steroid injection in patients with cervical radicular pain due to FS. 相似文献