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991.
This study was conducted to evaluate the predictive value of spleen stiffness-spleen size-to-platelet ratio risk score (SSPS) as a noninvasive predictor of esophageal varices (EVs) and to compare it with others.In this retrospective study, from April 2017 to October 2018, a total of 65 patients with hepatitis B virus-related cirrhosis who underwent the liver and spleen stiffness (LS, and SS) measurements by 2 dimensional-shear wave elastography and endoscopic evaluation for EVs were enrolled. Liver stiffness-spleen size-to-platelet ratio risk score (LSPS) and SSPS were calculated. The prognostic values were assessed by the area under the receiver operating characteristic curve (AUC).Twenty-six patients had no EV on endoscopy. Among 39 patients who had EVs, 12 patients had high risk EVs. The AUCs of the LS value, SS value, LSPS, and SSPS for predicting EVs were 0.72, 0.77, 0.80, and 0.85, respectively. The AUCs of the LS value, SS value, LSPS, and SSPS for predicting high-risk EVs were 0.55, 0.78, 0.67, and 0.80, respectively. SSPS had the highest specificity, at 96.15%, for predicting EVs.SSPS may be beneficial to exclude from having EVs and it is expected that the frequency of performing endoscopies for screening EVs can be reduced. 相似文献
992.
Buzhou Xu Hao Tang Yiming Weng Valerie Sloane Jones Shuhong Luo Chih Yun Cho Yongping Lin Jianmin Fang Xuedong Song RuoPan Huang 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundThe spread of COVID‐19 worldwide caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has necessitated efficient, sensitive diagnostic methods to identify infected people. We report on the development of a rapid 15‐minute time‐resolved fluorescent (TRF) lateral flow immunochromatographic assay for the quantitative detection of the SARS‐CoV‐2 spike protein receptor‐binding domain (S1‐RBD).ObjectivesOur objective was to develop an efficient method of detecting SARS‐CoV‐2 within 15 min of sample collection.MethodsWe constructed and evaluated a portable, disposable lateral flow device, which detected the S1‐RBD protein directly in nasopharyngeal swab samples. The device emits a fluorescent signal in the presence of S1‐RBD, which can be captured by an automated TRF instrument.ResultsThe TRF lateral flow assay signal was linear from 0 to 20 ng/ml and demonstrated high accuracy and reproducibility. When evaluated with clinical nasopharyngeal swabs, the assay was performed at >80% sensitivity, >84% specificity, and > 82% accuracy for detection of the S1‐RBD antigen.ConclusionThe new S1‐RBD antigen test is a rapid (15 min), sensitive, and specific assay that requires minimal sample preparation. Critically, the assay correlated closely with PCR‐based methodology in nasopharyngeal swab samples, showing that the detected S1‐RBD antigen levels correlate with SARS‐CoV‐2 virus load. Therefore, the new TRF lateral flow test for S1‐RBD has potential application in point‐of‐care settings. 相似文献
993.
Do Thi Ha Quan Cheng Chen Tran Manh Hung Ui Joung Youn Tran Minh Ngoc Phuong Thien Thuong Hong Jin Kim Yeon Hee Seong Byung Sun Min KiHwan Bae 《Archives of pharmacal research》2009,32(2):177-183
Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), gnetin H (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)-ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates
were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC50 values ranging from 15.7 ± 2.1 to 30.9 ± 1.8 μM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC50 values of 30.6 ± 4.1 and 28.7 ± 2.81 μM, respectively) and K562 (IC50 values of 38.6 ± 0.82 and 24.6 ± 0.76 μM, respectively). Gnetin H (4) showed only weak cytotoxic activity against L1210 with an IC50 value of 40.1 ± 4.23 μM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), (+)-ampelopsin F (7), and piceatannol (9) exhibited no activity on three cancer cell lines. 相似文献
994.
Katsuhiro Yamasaki Takaomi Tagami Masami Kawaguchi Masahiro Okihashi Satoshi Takatori Yoshikazu Sakagami Setsuko Sekita Motoyoshi Satake 《Journal of natural medicines》2009,63(4):451-458
Simple and rapid analysis of aristolochic acid (AA) in crude drugs and Kampo extracts using a solid-phase extraction method
and HPLC-PDA analysis was investigated. Extraction of AA from samples was accomplished by adding methanol containing 1% ammonia.
The addition of ammonia ionized the AA of acidic substances so that they adhered to an acrylamide copolymer of a strong anion
exchange resin (Sep-Pak QMA) coupled to diol silica easily. Furthermore, a mixture of acetonitrile–water–phosphoric acid (75:25:2,
v/v) was effective in isolating AA from its carrier. Since almost all interfering peaks originating from contaminants in crude
drugs and Kampo extract formulations could be removed, a satisfactory HPLC chromatogram of AA was obtained. A good result
was also obtained when Aristolochiaceae and crude drugs containing AA were tested. Particularly in the case of the medicinal
parts of Asarum, several interfering peaks and a ghost peak detected near the AA peak were eliminated. The AA contents of two Kampo extract
formulations, tokishigyakukagoshuyushokyoto and ryutanshakanto, were calculated by HPLC analysis. The AA content (the sum
of AA-I and AA-II) was 1.25–6.13 mg per daily dose. From an additional recovery experiment for Kampo formulations, high recovery
rates of AA were obtained. Neither LC/MS nor special instrumentation was necessary. Our results suggest that this simple,
quick, and sensitive analytical method to detect AA in crude drugs and Kampo extract formulations would be valuable in safety
inspections of AA in crude drugs and their products. 相似文献
995.
Tewa-Tagne P Degobert G Briançon S Bordes C Gauvrit JY Lanteri P Fessi H 《Pharmaceutical research》2007,24(4):650-661
Purpose Spray-drying process was used for the development of dried polymeric nanocapsules. The purpose of this research was to investigate
the effects of formulation and process variables on the resulting powder characteristics in order to optimize them.
Materials and Methods Experimental designs were used in order to estimate the influence of formulation parameters (nanocapsules and silica concentrations)
and process variables (inlet temperature, spray-flow air, feed flow rate and drying air flow rate) on spray-dried nanocapsules
when using silica as drying auxiliary agent. The interactions among the formulation parameters and process variables were
also studied. Responses analyzed for computing these effects and interactions were outlet temperature, moisture content, operation
yield, particles size, and particulate density. Additional qualitative responses (particles morphology, powder behavior) were
also considered.
Results Nanocapsules and silica concentrations were the main factors influencing the yield, particulate density and particle size.
In addition, they were concerned for the only significant interactions occurring among two different variables. None of the
studied variables had major effect on the moisture content while the interaction between nanocapsules and silica in the feed
was of first interest and determinant for both the qualitative and quantitative responses. The particles morphology depended
on the feed formulation but was unaffected by the process conditions.
Conclusion This study demonstrated that drying nanocapsules using silica as auxiliary agent by spray drying process enables the obtaining
of dried micronic particle size. The optimization of the process and the formulation variables resulted in a considerable
improvement of product yield while minimizing the moisture content. 相似文献
996.
Chang-Johng Kim Seung-Kil Cho Myung-Su Shin Hyun Cho Dong-Suk Ro Jong-Sei Park Chang-Soo Yook 《Archives of pharmacal research》1990,13(4):371-373
The hypoglycemic activity of water extracts of fifty six medicinal plants were evaluated in the streptozotocin-induced diabetic
mice. Twelve medicinal plants have significantly antidiabetic activity; Mori Radicis Cortex, Kwang Fang Chi Radix, Paeoniae
Radix, Eugeniae Flos, Atractylodis Rhizoma, Ophiopogonis Tuber, Rosae multiflorae Fructus, Glycyrrhizae Radix, Tetrapanacis
Medulla, Bigno, Forsythiae Fructus and Sophorae Radix. 相似文献
997.
Y.-M. Cho T. Imai Y. Ito S. Takami M. Hasumura T. Yamazaki M. Hirose A. Nishikawa 《Food and chemical toxicology》2009
A subchronic toxicity study of soybean extract was performed in F344 rats with dietary administration at concentrations of 0%, 1.25%, 2.5% and 5% for 13 weeks. No mortality or abnormal clinical signs in any group were observed. Body weight gains were decreased with a tendency for reduction of feed intake in the 1.25% and above female and 5% male groups. In males, absolute and relative liver weights were increased in the 1.25% and above groups. In females relative kidney weights were increased in the 1.25% and above groups. Other significant changes such as decreased RBC and hematocrit and increased urea nitrogen were detected in the 2.5% and/or 5% groups. On histopathological observation, atrophy of the ventral prostate was observed in all animals in the 5% male group. Mucification and atrophy of the vaginal epithelium and increased atretic follicles in ovaries were noted in 2.5% and 5% female rats. Based on the above findings the lowest-observed-adverse-effect level for male and female rats was estimated to be 1.25% (707.2 and 751.8 mg/kg b.w./day, respectively). 相似文献
998.
Sreekanth Thota Srujana Vallala Rajeshwar Yerra Daniel Alencar Rodrigues Eliezer J. Barreiro 《Medicinal chemistry research》2016,25(10):2127-2132
The synthesis and characterization of ruthenium complexes (Ru-1–Ru-6) of the type [Ru(R)2(K)]2+ (where R?=?1,10-phenanthroline/2,2′-bipyridyl and K?=?acetyl coumarin-inh, pyrazole-tch, acetyl coumarin-tsz, are described. These ligands form bidentate octahedral ruthenium complexes. The in vitro cytotoxic activities of the complexes measurement against the human cancer T-lymphocyte cell lines. In vitro evaluation of these title complexes revealed cytotoxicity from 0.34 to 1.4?µg/mL against CEM, 0.28 to 1.8?µg/mL against L1210, 0.44 to 2.5?µg/mL against Molt4/C8, 0.98 to 1.6?µg/mL against HL60, and 0.66 to 1.4?µg/mL against BEL7402. Ruthenium complexes Ru-5 & Ru-6 showed that quite significant anticancer activities over standard drugs. 相似文献
999.
C型钠尿肽抑制大鼠胃窦环行肌自发性收缩活动 总被引:3,自引:0,他引:3
Guo HS Cui X Cui YG Kim SZ Cho KW Li ZL Xu WX 《Acta pharmacologica Sinica》2003,24(10):1021-1026,1062
目的:研究钠尿肽对胃动力的作用及其可能的机制.方法:用四道记录仪记录胃窦环行肌条的自发性收缩活动;利用放射免疫技术测定cGMP的产生量;利用放射自显影技术分析钠尿肽受体在胃内的分布情况.结果:钠尿肽受体在大鼠胃的不同部位均有分布,但在胃窦部最多。ANP、BNP和CNP均能抑制胃窦环行肌条的自发性收缩,其中,CNP的作用尤为明显并呈剂量依赖关系.CNP的这种抑制性作用被鸟苷酸环化酶抑制剂LY83583所削弱,而用cGMF敏感的磷酸酯酶抑制剂zaparinist预处理时CNP的抑制作用明显增加.CNP明显提高胃窦环行肌cGMP的浓度.用非选择性钾通道阻断剂TEA预处理后发现CNP对胃窦环行肌自发性收缩活动的抑制作用明显减弱.结论:钠尿肽受体在大鼠的胃窦分布最多.CNP明显抑制大鼠胃窦环行肌的自发性收缩活动.CNP对大鼠胃窦环行肌自发性收缩活动的抑制效应是通过cGMP途径实现的.钾通道也参与CNP对大鼠胃窦平滑肌的舒张过程。 相似文献
1000.
Sequential effects of cadmium on genotoxicity and lipoperoxidation in <Emphasis Type="Italic">Vicia faba</Emphasis> roots 总被引:1,自引:0,他引:1
Kinetics of stress responses to Cd exposure (50, 100 and 200 μM) expanding from 12 to 48 h were studied in roots of hydroponically
cultivated-Vicia faba seedlings. The heavy metal induced toxicity symptoms and growth arrest of Vicia roots gradually to the Cd concentration and duration of the treatment. The intracellular oxidative stress was evaluated with
the H2O2 production. The H2O2 content increased gradually with the sequestered Cd and root growth inhibition. Lipid peroxidation—evidenced by malondialdehyde
(MDA) content and Evans blue uptake—and genotoxicity—evidenced by mitotic index (MI) and micronuclei (MCN) values—were concomitantly
investigated in root tips. By 12 h, root meristematic cells lost 15% of their mitotic activity under 50 or 100 μM Cd treatment
and 50% under 200 μM Cd treatment and led cells with MCN, while the MDA content and Evans blue absorption were not affected.
The loss of membrane integrity occurred subsequently by 24 h. The increase in MDA content in root cells treated with 50, 100
and 200 μM Cd was significantly higher than the control. By 48 h, the MDA content increased 134, 178 or 208% in root cells
treated with 50, 100 and 200 μM Cd, respectively. The Evans blue absorption was also affected by 24 h in roots when treated
with 200 μM Cd and gradually increase by 48 h with the Cd concentration of the treatment. The decrease of mitotic activity
triggered by 12 h was even higher by 24 h and the MI reduced to 44, 56 or 80% compared to the control in the three different
Cd concentrations tested. The different kinetics of early in vivo physiological and cytogenetic responses to Cd might be relevant
to the characterization of its toxicity mechanisms in disrupting primarily the mitosis process. 相似文献