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31.
Greve H Kehraus S Krick A Kelter G Maier A Fiebig HH Wright AD König GM 《Journal of natural products》2008,71(3):309-312
A new cytotoxic bastadin, bastadin 24 ( 1), and the previously reported bastadins 4, 5, 6, 7, 12, 13, and 21 ( 2- 8) were isolated from a polar extract of the Australian marine sponge Ianthella quadrangulata. The planar structure of bastadin 24 ( 1) was elucidated as the 25-hydroxy derivative of bastadin 6 ( 4) by employing spectroscopic techniques (NMR, MS, UV, and IR). All isolated bastadins were evaluated for their cytotoxicity toward a panel of 36 human tumor cell lines and were found to be moderately cytotoxic. Bastadin 24 ( 1) exhibited selective cytotoxic activity toward five of the 36 investigated tumor cell lines. Bastadins 7 ( 5) and 12 ( 6) significantly inhibited the serum + hEGF-induced (human epithelial growth factor) tubular formation of human umbilical vein endothelial cells (HUVEC) at a concentration of 1 mug/mL. 相似文献
32.
Prenatal diagnosis of xeroderma pigmentosum and trichothiodystrophy in 76 pregnancies at risk 总被引:1,自引:0,他引:1
Kleijer WJ van der Sterre ML Garritsen VH Raams A Jaspers NG 《Prenatal diagnosis》2007,27(12):1133-1137
OBJECTIVE: Evaluation of results in a consecutive series of 76 prenatal diagnoses for xeroderma pigmentosum (XP) and trichothiodystrophy (TTD) made since 1977. METHODS: UV-induced DNA repair synthesis was assessed by the autoradiographic measurement of the incorporation of (3)H-thymidine. RESULTS: XP was diagnosed in 19 of the 76 investigated pregnancies at risk; cultured chorionic villus (CV) cells were used in 33 pregnancies with ten affected fetuses and cultured amniocytes in 43 pregnancies with nine affected fetuses. In four cases, CVS results were corroborated by subsequent investigation of amniocytes because maternal cell contamination in the CV cell culture was either present or could not be excluded. Uncertain results in two other cases with intermediate DNA repair capacity and severe maternal cell contamination required further investigation. Median time needed for cell culture and analysis was 25 days. To reduce intra-assay variations, a modification of the DNA repair synthesis assay has recently been developed. In this assay, patients and controls are investigated simultaneously in mixed cultures of cells labelled with polystyrene beads. CONCLUSION: Reliable prenatal diagnosis for XP and TTD can be made by the demonstration of clearly reduced UV-induced DNA repair synthesis due to defective global genome nucleotide excision repair. 相似文献
33.
Michael Schaefer Anja Kühnel Franziska Rumpel Matti Grtner 《Social cognitive and affective neuroscience》2022,17(5):437
Giving and receiving touch are some of the most important social stimuli we exchange in daily life. By touching someone, we can communicate various types of information. Previous studies have also demonstrated that interpersonal touch may affect our altruistic behavior. A classic study showed that customers give bigger tips when they are lightly touched by a waitress, which has been called the Midas touch effect. Numerous studies reported similar effects of touch on different kinds of helping or prosocial behaviors. Here, we aim to examine the neural underpinnings of this effect by employing a functional magnetic resonance imaging approach. While lying in the scanner, participants played different rounds of the dictator game, a measure of prosocial behavior. Before each round, participants were touched (or not touched in the control condition) by an experimenter. We found that touching the hand increased the likeliness to behave prosocial (but not the general liking of control stimuli), thereby confirming the Midas touch effect. The effect was predicted by activity in the primary somatosensory cortex, indicating that the somatosensory cortex here plays a causal role in prosocial behavior. We conclude that the tactile modality in social life may be much more important than previously thought. 相似文献
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Interest in plant-based nutrition has steadily increased in the western world in the recent years. The number of people following a meat-reduced, flexitarian diet is growing continuously. However, little is known about the diet quality of flexitarians compared to vegans or omnivores. Therefore, in this cross-sectional study, the food intake of 94 participants aged between 25–45 years was recorded via a validated food frequency questionnaire and 28 self-designed questions about the consumption of plant-based alternatives. An adapted Healthy Eating Index, HEI-flex, was developed to evaluate the diet quality of flexitarians, vegans and omnivores. Higher score points (SP) of the HEI-flex are associated with higher compliance with the official diet recommendations (Vmax = 100 SP). Finally, flexitarians scored significantly more highly when compared to omnivores (54 ± 8 vs. 47 ± 9 SP; p = 0.008) but lower than vegans (54 ± 8 vs. 61 ± 10 SP; p = 0.010). The results showed that the HEI-flex is a useful tool for assessing and comparing the diet quality of flexitarians, vegans and omnivores. Despite the consumption of highly processed plant-based alternatives, reduction in meat and meat products seems to be accompanied by increased overall diet quality. 相似文献
36.
Anja C. M. de Bruin Mathis Funk Monique I. Spronken Alexander P. Gultyaev Ron A. M. Fouchier Mathilde Richard 《Viruses》2022,14(7)
Highly Pathogenic Avian Influenza Viruses (HPAIVs) arise from low pathogenic precursors following spillover from wild waterfowl into poultry populations. The main virulence determinant of HPAIVs is the presence of a multi-basic cleavage site (MBCS) in the hemagglutinin (HA) glycoprotein. The MBCS allows for HA cleavage and, consequently, activation by ubiquitous proteases, which results in systemic dissemination in terrestrial poultry. Since 1959, 51 independent MBCS acquisition events have been documented, virtually all in HA from the H5 and H7 subtypes. In the present article, data from natural LPAIV to HPAIV conversions and experimental in vitro and in vivo studies were reviewed in order to compile recent advances in understanding HA cleavage efficiency, protease usage, and MBCS acquisition mechanisms. Finally, recent hypotheses that might explain the unique predisposition of the H5 and H7 HA sequences to obtain an MBCS in nature are discussed. 相似文献
37.
Jelle Koopsen Catharina E. van Ewijk Roisin Bavalia Akke Cornelissen Sylvia M. Bruisten Floor de Gee Alvin X. Han Maarten de Jong Menno D. de Jong Marcel Jonges Norin Khawaja Fleur M.H.P.A. Koene Mariken van der Lubben Iris Mikulic Sjoerd P.H. Rebers Colin A. Russell Janke Schinkel Anja J.M. Schreijer Judith A. den Uil Matthijs R.A. Welkers Tjalling Leenstra 《Emerging infectious diseases》2022,28(5):1012
We report a severe acute respiratory syndrome coronavirus 2 superspreading event in the Netherlands after distancing rules were lifted in nightclubs, despite requiring a negative test or vaccination. This occurrence illustrates the potential for rapid dissemination of variants in largely unvaccinated populations under such conditions. We detected subsequent community transmission of this strain. 相似文献
38.
Anja Lazi Miodrag Koci Neboja Trajkovi Cristian Popa Leonardo Alexandre Peyr-Tartaruga Johnny Padulo 《Nutrients》2022,14(9)
Caffeine supplementation has become increasingly popular among athletes. The benefits of caffeine include delaying the negative effects of fatigue, maintaining a high level of physical and mental performance, and improving certain abilities necessary for sport success. Given the complex nature of basketball, caffeine could be a legal, ergogenic stimulant substance, which will positively affect overall basketball performance. The purpose of this systematic review was to summarize evidence for the effect of acute caffeine ingestion on variables related to the basketball performance. Web of Science, PubMed, Scopus and ProQuest, MEDLINE, and ERIC databases were searched up to February 2021. Studies that measured the acute effect of caffeine on basketball performance were included and analyzed. Eight studies published between 2000 and 2021 were included in the analysis. Pre-exercise caffeine intake increased vertical jump height, running time at 10 and 20 m without the ball, overall basketball performance (number of body impacts, number of free throws, rebounds, and assists) during simulated games, and reduced the time required to perform a basketball-specific agility test. Equivocal results between caffeine and placebo groups were found for aerobic capacity, free throw and three-point accuracy, and dribbling speed. Pre-exercise caffeine ingestion did not affect RPE, but insomnia and urinary excretion were increased. The pre-exercise ingestion of 3 and 6 mg/kg caffeine was found to be effective in increasing several physical performance variables in basketball players during sport-specific testing and simulated matches. However, considering the intermittent nature and complexity of basketball, and individual differences between players, future studies are needed. 相似文献
39.
40.
Alternating versus concurrent schedules of imatinib and chemotherapy as front-line therapy for Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) 总被引:18,自引:0,他引:18 下载免费PDF全文
Wassmann B Pfeifer H Goekbuget N Beelen DW Beck J Stelljes M Bornhäuser M Reichle A Perz J Haas R Ganser A Schmid M Kanz L Lenz G Kaufmann M Binckebanck A Brück P Reutzel R Gschaidmeier H Schwartz S Hoelzer D Ottmann OG 《Blood》2006,108(5):1469-1477
The best strategy for incorporating imatinib in front-line treatment of Ph+ acute lymphoblastic leukemia (ALL) has not been established. We enrolled 92 patients with newly diagnosed Ph+ ALL in a prospective, multicenter study to investigate sequentially 2 treatment schedules with imatinib administered concurrent to or alternating with a uniform induction and consolidation regimen. Coadministration of imatinib and induction cycle 2 (INDII) resulted in a complete remission (CR) rate of 95% and polymerase chain reaction (PCR) negativity for BCR-ABL in 52% of patients, compared with 19% in patients in the alternating treatment cohort (P = .01). Remarkably, patients with and without a CR after induction cycle 1 (INDI) had similar hematologic and molecular responses after concurrent imatinib and INDII. In the concurrent cohort, grades III and IV cytopenias and transient hepatotoxicity necessitated interruption of induction in 87% and 53% of patients, respectively; however, duration of induction was not prolonged when compared with patients receiving chemotherapy alone. No imatinib-related severe hematologic or nonhematologic toxicities were noted with the alternating schedule. In each cohort, 77% of patients underwent allogeneic stem cell transplantation (SCT) in first CR (CR1). Both schedules of imatinib have acceptable toxicity and facilitate SCT in CR1 in the majority of patients, but concurrent administration of imatinib and chemotherapy has greater antileukemic efficacy. 相似文献