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Irene Jao Vicki Marsh Primus Che Chi Melissa Kapulu Mainga Hamaluba Sassy Molyneux Philip Bejon Dorcas Kamuya 《Bioethics》2020,34(8):819-832
Controlled human malaria infection (CHMI) studies involve the deliberate infection of healthy volunteers with malaria parasites under controlled conditions to study immune responses and/or test drug or vaccine efficacy. An empirical ethics study was embedded in a CHMI study at a Kenyan research programme to explore stakeholders’ perceptions and experiences of deliberate infection and moral implications of these. Data for this qualitative study were collected through focus group discussions, in-depth interviews and non-participant observation. Sixty-nine participants were involved, including CHMI study volunteers, community representatives and research staff. Data were managed using QSR Nvivo 10 and analysed using an inductive-deductive approach, guided by ethics literature. CHMI volunteers had reasonable understanding of the study procedures. Decisions to join were influenced by study incentives, trust in the research institution, their assessment of associated burdens and motivation to support malaria vaccine development. However, deliberate malaria infection was a highly unusual research strategy for volunteers, community representatives and some study staff. Volunteers’ experiences of physical, emotional and social burdens or harms were often greater than anticipated initially, and fluctuated over time, related to specific procedures and events. Although unlikely to deter volunteers' participation in similar studies in furture, we argue that the dissonance between level of understanding of the burdens involved and actual experiences are morally relevant in relation to community engagement, informed consent processes, and ongoing support for volunteers and research staff. We further argue that ethics oversight of CHMI studies should take account of these issues in deciding whether consent, engagement and the balance of benefits and harms are reasonable in a given context. 相似文献
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Demet Tademir Ayegül Karaküük‐yidoan Mustafa Ulali Tuba Takin‐Tok Emne Eln Oru‐Emre Hasan Bayram 《Chirality》2015,27(2):177-188
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
5.
Ibrahim Che Omar Hisashi Saeki Naomichi Nishio Shiro Nagai 《Biotechnology letters》1989,11(3):161-166
Summary The applications of immobilized lipase ofMucor miehei for the synthesis of acetone glycerol acyl ester from acetone glycerol and fatty acid, which is the first step for monoglyceride production was investigated. With a high oleic acid to acetone glycerol ratio (O/A, mol/mol), a high catalytic activity was observed under low water content in the reaction mixture. By the combination of high O/A ratio (>3) and removal of water which was produced during the reaction, the conversion degree was increased to almost 100%. With the O/A ratio of 3, the approximate half-life of the immobilized lipase and productivity of ester was estimated to be 20 days and 869 g product/g immobilized enzyme per 2 half-lives, respectively. 相似文献
6.
Autonomous DNA binding domains of lambda integrase recognize two different sequence families 总被引:35,自引:0,他引:35
The 40 kd lambda Integrase protein is shown to contain two autonomous DNA binding domains with different sequence specificities. Competition experiments in which the binding activity of Int is assayed through nuclease protection demonstrate the functional independence of the two DNA recognition specificities. Proteolytic cleavage of Int and footprinting analysis of the resulting two major peptides allow the physical separation and identification of two DNA binding domains: an amino-terminal peptide that interacts with "arm-type" sites and a carboxy-terminal peptide that binds to "core-type" sequences. In addition, the data suggest that the two domains can bind DNA simultaneously, consistent with a model in which Integrase would link two disparate DNA sequences. 相似文献
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Summary Snake flask experiments were carried out as a preliminary study of fat formation byTrichoderma
reesei (formallyviride) QM 9123 using a glucose based medium. The maximum quantity of fat production was 16% of the dry weight. The pH of the medium, as much as its composition, appeared to influence the quantity of fat that was produced. The fatty acids formed by the hydrolysis of the fats were found to be mainly unsaturated, with the 182 (linoleic) acid predominating. 相似文献
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人小细胞肺癌的发病率虽不及非小细胞肺癌,但其五年生存率却相对低得多,这两种细胞类型不仅在病理类型上表现不同,在许多其它性质上也表现不同。小细胞肺癌是一种异质性疾病,它由几种形态不同的瘤细胞组成,包括非小细胞肺癌在内;它易早期转移,能在肝、脑和骨髓中繁殖,具有L-Dopa胱羧酶,神经原特异的烯醇化酶(enolase),能合成神经递质和多肽激素蛙皮肽等特性。目前已有关于小细胞肺癌的单克隆抗体的报道,我们采用美国N I H建立的小细胞肺癌细胞株SH-77作免疫原,目前尚未见有关抗该细胞株的单克隆抗体的报道,现将我们制备的三个单抗体及其初步特异性鉴定结果简报如下 相似文献
9.
S. I. Hasan Barbara A. D. Blaney J. L. Turk 《Cancer immunology, immunotherapy : CII》1992,34(4):228-232
Summary This study investigates the effects of anticancer drugs and immunomodulating agents on the release of interleukin-6 (IL-6) from lipopolysaccharide-stimulated human peripheral blood mononuclear leucocytes in vitro. The addition of non-cytotoxic concentrations of Adriamycin (doxorubicin), vincristine and 4-OOH-cyclophosphamide (the in vitro active analogue of cyclophosphamide) resulted in suppression of IL-6 release. The drugs bleomycin, FK156 [d-lactoyl-l-alanyl--d-glutamyl-(l)-meso-diaminopimelyl-(l)-glycine], FK565 [heptanoyl--d-glutamyl-(l)-meso-diaminopimelyl-(d)-alanine] and the immunosuppressive agent cyclosporin A did not alter the release of IL-6 in the same experimental system. 相似文献
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A new saponin, leucasin, has been isolated from Leucas nutans and characterized on the basis of chemical investigation and spectroscopic studies as 3-O-[β-
-glucopyranosyl(1→2)β-
-glucopyranosyl]2,3β-dihydroxylup-20(29)-ene. Lupeol palmitate, sitosterol and stigmasterol were also isolated. 相似文献