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31.
Aumont V Larronde F Richard T Budzinski H Decendit A Deffieux G Krisa S Mérillon JM 《Journal of biotechnology》2004,109(3):287-294
The use of Vitis vinifera cells grown in a 2 l-stirred tank bioreactor for producing isotopically 13C-labeled phenolic substances is presented. Several culture parameters were optimized to achieve characteristics of growth and polyphenol metabolism similar to that recorded in shake flasks. Administration of [1-13C]L-phenylalanine (3 mM) to grape cell suspension cultures led to the production of 13C-labeled stilbenes (trans- and cis-piceids), catechins (catechin and epicatechin) and anthocyanins (delphinidin-, cyanidin-, petunidin-, peonidin- and malvidin-3-O-beta-glucosides). Incorporation of [1-13C]L-phenylalanine into polyphenols was measured by means of 13C satellites in the proton NMR spectrum and EA-IRMS. The enrichment of labeling obtained for all the compounds (between 40 and 65%) is sufficient to investigate their absorption and metabolism in humans. 相似文献
32.
Elliott RL Oliver RM LaFlamme JA Gillaspy ML Hammond M Hank RF Maurer TS Baker DL DaSilva-Jardine PA Stevenson RW Mack CM Cassella JV 《Bioorganic & medicinal chemistry letters》2003,13(20):3593-3596
A series of 2-heteroaryl-4-arylimidazoles with potent in vitro activity at the NPY5 receptor was developed. Introduction of electron-withdrawing groups on the 4-aryl ring led to a significant improvement of in vitro potency. Several analogues from this series had anorectic activity in rodent feeding models, but were also found to have undesired behavioral effects in spontaneous locomotor activity. 相似文献
33.
Daun JM Ball RW Cannon JG 《American journal of physiology. Regulatory, integrative and comparative physiology》2000,278(4):R855-R862
Interleukin-1 (IL-1) is a primary mediator of inflammation that is regulated, in part, by the hypothalamic-pituitary-adrenal axis. The purpose of this study was to determine if gender- or age-related differences exist in the sensitivity of IL-1-producing cells to hydrocortisone. Peripheral blood mononuclear cells (PBMC) isolated from men and women (21-77 yr old) were incubated with hydrocortisone (0, 50, 100, 500, or 1,000 ng/ml) with or without lipopolysaccharide (LPS). Secretion of IL-1beta and IL-1 receptor antagonist was inhibited in a dose-dependent manner (P = 0.001) without age- or gender-related differences. Hydrocortisone decreased soluble IL-1 receptor type II (sIL-1RII) secretion by unstimulated cells (P = 0. 0001), but it increased secretion by LPS-stimulated cells (P = 0. 0001) in all groups. Unstimulated cell supernatants from men contained greater concentrations of sIL-1RII than the supernatants from women (P = 0.011). Compared with men, PBMCs from women were less responsive to hydrocortisone inhibition of sIL-1RII secretion, regardless of age (P = 0.001), and compared with the follicular phase, sIL-1RII secretion was lower in the luteal phase of the menstrual cycle (P < 0.05). These data indicate that basal secretion and glucocorticoid modulation of sIL-1RII secretion by cultured PBMCs are gender dependent. Moreover, glucocorticoid influences on sIL-1RII secretion depend on the presence or absence of gram-negative bacterial toxins. 相似文献
34.
In order to study gravity effects on plant structure and function, it may become necessary to remove the g-stimulus. On Earth, various instruments such as clinostats have been used by biologists in an attempt to neutralize the effects
of gravity. In this study, the position of amyloplasts was assayed in columella cells in the roots of Arabidopsisthaliana (L.) Heynh. seedlings grown in the following conditions: on Earth, on a two-dimensional clinostat at 1 rpm, on a three-dimensional
clinostat (also called a random-positioning machine, or an RPM), and in space (true microgravity). In addition, the effects
of these gravity treatments on columella cell area and plastid area also were measured. In terms of the parameters measured,
only amyloplast position was affected by the gravity treatments. Plastid position was not significantly different between
spaceflight and RPM conditions but was significantly different between spaceflight and the classical two-dimensional clinostat
treatments. Flanking columella cells showed a greater susceptibility to changes in gravity compared to the central columella
cells. In addition, columella cells of seedlings that were grown on the RPM did not exhibit deleterious effects in terms of
their ultrastructure as has been reported previously for seedlings grown on a two-dimensional clinostat. This study supports
the hypothesis that the RPM provides a useful simulation of weightlessness.
Received: 5 January 2000 / Accepted: 22 February 2000 相似文献
35.
Macrophages play important roles in defense against infection, as well as in homeostasis maintenance. Thus alterations of macrophage function can have unexpected pathological results. Cyclooxygenase (COX) inhibitors are widely used to relieve pain, but the effects of long-term usage on macrophage function remain to be elucidated. Using bone marrow-derived macrophage culture and long-term COX inhibitor treatments in BALB/c mice and zebrafish, we showed that chronic COX inhibition drives macrophages into an inflammatory state. Macrophages differentiated in the presence of SC-560 (COX-1 inhibitor), NS-398 (COX-2 inhibitor) or indomethacin (COX-1/2 inhibitor) for 7 days produced more TNFα or IL-12p70 with enhanced p65/IκB phosphoylation. YmI and IRF4 expression was reduced significantly, indicative of a more inflammatory phenotype. We further observed that indomethacin or NS-398 delivery accelerated zebrafish death rates during LPS induced sepsis. When COX inhibitors were released over 30 days from an osmotic pump implant in mice, macrophages from peritoneal cavities and adipose tissue produced more TNFα in both the basal state and under LPS stimulation. Consequently, indomethacin-exposed mice showed accelerated systemic inflammation after LPS injection. Our findings suggest that macrophages exhibit a more inflammatory phenotype when COX activities are chronically inhibited. 相似文献
36.
Qiang Tong Qing Cai Tristan de Mooij Xia Xu Shengming Dai Wenchun Qu Dongbao Zhao 《PloS one》2015,10(3)
Objective
This study aims to investigate the prevalence of short-term and long-term adverse events associated with tumor necrosis factor-α (TNF-α) blocker treatment in Chinese Han patients suffering from ankylosing spondylitis (AS).Methods
The study included 402 Chinese Han AS patients treated with TNF-α blockers. Baseline data was collected. All patients were monitored for adverse events 2 hours following administration. Long-term treatment was evaluated at 8, 12, 52 and 104 weeks follow-up for 172 patients treated with TNF-α blockers.Results
Short-term adverse events occurred in 20.15% (81/402), including rash (3.5%; 14/402), pruritus (1.2%; 5/402), nausea (2.2%; 9/402), headache (0.7%; 3/402), skin allergies (4.0%; 16/402), fever (0.5%; 2/402), palpitations (3.0%; 12/402), dyspnea (0.5%; 2/402), chest pain (0.2%; 2/402), abdominal pain (1.0%; 4/402), hypertension (2.2%; 9/402), papilledema (0.5%; 2/402), laryngeal edema (0.2%; 1/402) and premature ventricular contraction (0.2%; 1/402). Long-term adverse events occurred in 59 (34.3%; 59/172) patients, including pneumonia (7.6%; 13/172), urinary tract infections (9.9%; 17/172), otitis media (4.7%; 8/172), tuberculosis (3.5%; 17/172), abscess (1.2%; 2/172), oral candidiasis (0.6%; 1/172), elevation of transaminase (1.7%; 3/172), anemia (1.2%; 2/172), hematuresis (0.6%; 1/172), constipation (2.3%; 4/172), weight loss (0.6%; 1/172), exfoliative dermatitis (0.6%; 1/172). CRP, ESR and disease duration were found to be associated with an increased risk of immediate and long-term adverse events (P<0.05). Long-term treatment with Infliximab was associated with more adverse events than rhTNFR-Fc (P<0.01).Conclusion
This study reports on the prevalence of adverse events in short-term and long-term treatment with TNF-α blocker monotherapy in Chinese Han AS patients. Duration of disease, erythrocyte sedimentation rate, and c-reactive protein serum levels were found to be associated with increased adverse events with anti-TNF-α therapy. Long-term treatment with Infliximab was associated with more adverse events than rhTNFR-Fc. 相似文献37.
Since 2008, mass mortality outbreaks have been reported in all French regions producing Pacific oysters, and in several Member States of the European Union. These mass mortality events of Pacific oysters are related to OsHV-1 infection. They occur during spring and summer periods leaving suspect the quality of the marine environment and the role of seasonal use of pesticides associated with the arrival of freshwater in oyster rearing areas. Pesticides have been also detected in French coastal waters, especially in areas of oyster production. Using PMA real-time PCR we showed that a mixture of 14 pesticides has no effect on the integrity of virus capsids from viral suspension in the conditions tested. A contact of oysters with this pesticide mixture was related to higher mortality rates among experimentally infected animals in comparison with control ones (no previous pesticide exposure before experimental infection). We therefore suggest that pesticides at realistic concentration can exert adverse effects on Pacific oysters and causes an increased susceptibility to the viral infection in experimental conditions. 相似文献
38.
Lionel Dégremont Jean-Baptiste Lamy Jean-Fran?ois Pépin Marie-Agnès Travers Tristan Renault 《PloS one》2015,10(6)
The Pacific oyster, Crassostrea gigas, is the most important commercial oyster species cultivated in the world. Meanwhile, the ostreid herpesvirus 1 (OsHV-1) is one of the major pathogens affecting the Pacific oyster, and numerous mortality outbreaks related to this pathogen are now reported worldwide. To assess the genetic basis of resistance to OsHV-1 infection in spat C. gigas and to facilitate breeding programs for such a trait, if any exist, we compared the mortality of half- and full-sib families using three field methods and a controlled challenge by OsHV-1 in the laboratory. In the field, three methods were tested: (A) one family per bag; (B) one family per small soft mesh bag and all families inside one bag; (C) same as the previous methods but the oysters were individually labelled and then mixed. The mean mortality ranged from 80 to 82% and was related to OsHV-1 based on viral DNA detection. The narrow-sense heritability for mortality, and thus OsHV-1 resistance, ranged from 0.49 to 0.60. The high positive genetic correlations across the field methods suggested no genotype by environment interaction. Ideally, selective breeding could use method B, which is less time- and space-consuming. The narrow sense heritability for mortality under OsHV-1 challenge was 0.61, and genetic correlation between the field and the laboratory was ranged from 0.68 to 0.75, suggesting a weak genotype by environment interaction. Thus, most of families showing the highest survival performed well in field and laboratory conditions, and a similar trend was also observed for families with the lowest survival. In conclusion, this is the first study demonstrating a large additive genetic variation for resistance to OsHV-1 infection in C. gigas, regardless of the methods used, which should help in selective breeding to improve resistance to viral infection in C. gigas. 相似文献
39.
Frédérique Thonon Rym Boulkedid Tristan Delory Sophie Rousseau Mahasti Saghatchian Wim van Harten Claire O’Neill Corinne Alberti 《PloS one》2015,10(4)
Background
There is an increasing need to evaluate the production and impact of medical research produced by institutions. Many indicators exist, yet we do not have enough information about their relevance. The objective of this systematic review was (1) to identify all the indicators that could be used to measure the output and outcome of medical research carried out in institutions and (2) enlist their methodology, use, positive and negative points.Methodology
We have searched 3 databases (Pubmed, Scopus, Web of Science) using the following keywords: [Research outcome* OR research output* OR bibliometric* OR scientometric* OR scientific production] AND [indicator* OR index* OR evaluation OR metrics]. We included articles presenting, discussing or evaluating indicators measuring the scientific production of an institution. The search was conducted by two independent authors using a standardised data extraction form. For each indicator we extracted its definition, calculation, its rationale and its positive and negative points. In order to reduce bias, data extraction and analysis was performed by two independent authors.Findings
We included 76 articles. A total of 57 indicators were identified. We have classified those indicators into 6 categories: 9 indicators of research activity, 24 indicators of scientific production and impact, 5 indicators of collaboration, 7 indicators of industrial production, 4 indicators of dissemination, 8 indicators of health service impact. The most widely discussed and described is the h-index with 31 articles discussing it.Discussion
The majority of indicators found are bibliometric indicators of scientific production and impact. Several indicators have been developed to improve the h-index. This indicator has also inspired the creation of two indicators to measure industrial production and collaboration. Several articles propose indicators measuring research impact without detailing a methodology for calculating them. Many bibliometric indicators identified have been created but have not been used or further discussed. 相似文献40.
Alexander W. Pfaff Alejandra de-la-Torre Elise Rochet Julie Brunet Marcela Sabou Arnaud Sauer Tristan Bourcier Jorge E. Gomez-Marin Ermanno Candolfi 《International journal for parasitology》2014
Retinal lesions or other ocular manifestations are serious consequences of infection with the protozoan parasite Toxoplasma gondii. Whilst classically considered a consequence of congenital transmission, recent screening studies estimated that 2% of T. gondii seropositive persons in Europe and North America have retinal lesions, most of them persisting unnoticed. The situation is more dramatic in South America, probably due to the predominance of virulent strains. Some of these strains seem to exhibit ocular or neuronal tropism and are responsible for severe ocular lesions. Despite the medical importance, the physiopathological mechanisms have only recently begun to be elucidated. The particular immune-privileged situation in the eye has to be considered. Studies on French patients showed low or undetectable ocular parasite loads, but a clear Th1/Th17 type immune reaction. Suitable mouse models have appeared in the last few years. Using such a model, IL-17A proved to impair parasite control and induce pathology. In contrast, in South American patients, the parasite seems to be much less efficiently controlled through a Th2 type or suppressive immune response that favors parasite replication. Finally, several host genetic markers controlling immune response factors have been associated with ocular involvement of T. gondii infection, mainly in South America. 相似文献