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1.
Richard B. Pouw Mieke C. Brouwer Judy Geissler Laurens V. van Herpen Sacha S. Zeerleder Walter A. Wuillemin Diana Wouters Taco W. Kuijpers 《PloS one》2016,11(3)
The major human complement regulator in blood, complement factor H (FH), has several closely related proteins, called FH-related (FHR) proteins. As all FHRs lack relevant complement regulatory activity, their physiological role is not well understood. FHR protein 3 (FHR-3) has been suggested to compete with FH for binding to Neisseria meningitidis, thereby affecting complement-mediated clearance. Clearly, the in vivo outcome of such competition greatly depends on the FH and FHR-3 concentrations. While FH levels have been established, accurate FHR-3 levels were never unequivocally reported to date. Moreover, CFHR3 gene copy numbers commonly vary, which may impact the FHR-3 concentration. Hence, we generated five anti-FHR-3 mAbs to specifically measure FHR-3 in human healthy donors of which we determined the gene copy number variation at the CFH/CFHR locus. Finally, we examined the acute-phase response characteristics of FHR-3 in a small sepsis cohort. We determined FHR-3 levels to have a mean of 19 nM and that under normal conditions the copy number of CFHR3 correlates to a very large extent with the FHR-3 serum levels. On average, FHR-3 was 132-fold lower compared to the FH concentration in the same serum samples and FHR-3 did not behave as a major acute phase response protein. 相似文献
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Gerben J. Van Eldik Miriam Wingens René K. Ruiter Marinus M. A. Van Herpen Jan A. M. Schrauwen George J. Wullems 《Plant molecular biology》1996,30(1):171-176
A gene, sts14, coding for a highly expressed mRNA in pistils of Solanum tuberosum, was isolated. Northern blot and in situ analyses demonstrated that the gene was expressed throughout pistil development in both the stylar cortex and the stigma. The deduced STS14 protein displays similarity to the pathogenesis-related PR-1 proteins. A possible function for protection or guidance of the pollen tubes through the pistil is discussed. 相似文献
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de Groot P Weterings K de Been M Wittink F Hulzink R Custers J van Herpen M Wullems G 《Plant molecular biology》2004,55(5):715-726
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Van Eldik G; Ruiter R; Van Herpen M; Schrawen J; Wullems G 《Journal of experimental botany》1998,49(325):1453-1454
The reproductive function of the pistil requires the production of
compounds essential for pollen tube growth. A cold-plaque screening of a
pollinated pistil cDNA library of Solanum tuberosum
resulted in the isolation of cDNA clone cp67. Northern blot analyses
revealed that cp67 is specifically expressed in potato pistils and in a
limited number of plant species. The deduced CP67 protein displays
similarity to long-chain zinc-containing alcohol dehydrogenases (ADHs),
although at a similarity level much lower than between other plant
ADHs. 相似文献
6.
Geertje van de Ven Irena Draskovic Elke van Herpen Raymond T. C. M. Koopmans Rogier Donders Sytse U. Zuidema Eddy M. M. Adang Myrra J. F. J. Vernooij-Dassen 《PloS one》2014,9(1)
Background
Dementia-care mapping (DCM) is a cyclic intervention aiming at reducing neuropsychiatric symptoms in people with dementia in nursing homes. Alongside an 18-month cluster-randomized controlled trial in which we studied the effectiveness of DCM on residents and staff outcomes, we investigated differences in costs of care between DCM and usual care in nursing homes.Methods
Dementia special care units were randomly assigned to DCM or usual care. Nurses from the intervention care homes received DCM training, a DCM organizational briefing day and conducted the 4-months DCM-intervention twice during the study. A single DCM cycle consists of observation, feedback to the staff, and action plans for the residents. We measured costs related to health care consumption, falls and psychotropic drug use at the resident level and absenteeism at the staff level. Data were extracted from resident files and the nursing home records. Prizes were determined using the Dutch manual of health care cost and the cost prices delivered by a pharmacy and a nursing home. Total costs were evaluated by means of linear mixed-effect models for longitudinal data, with the unit as a random effect to correct for dependencies within units.Results
34 units from 11 nursing homes, including 318 residents and 376 nursing staff members participated in the cost analyses. Analyses showed no difference in total costs. However certain changes within costs could be noticed. The intervention group showed lower costs associated with outpatient hospital appointments over time (p = 0.05) than the control group. In both groups, the number of falls, costs associated with the elderly-care physician and nurse practitioner increased equally during the study (p<0.02).Conclusions
DCM is a cost-neutral intervention. It effectively reduces outpatient hospital appointments compared to usual care. Other considerations than costs, such as nursing homes’ preferences, may determine whether they adopt the DCM method.Trial Registration
Dutch Trials Registry NTR2314 相似文献7.
M. M. A. Van Herpen P. F. M. de Groot J. A. M. Schrauwen K. J. P. T. van den Heuvel K. A. P. Weterings G. J. Wullems 《Sexual plant reproduction》1992,5(4):304-309
Summary Immature pollen grains of Nicotiana tabacum L., cv Petit Havana were isolated at the mid-binucleate stage and cultured in vitro. During the first 66 h of in-vitro culture the pollen developed the same ability to set seed and germinate as pollen matured in vivo. No fertile pollen was produced when protein synthesis was inhibited temporarily at an early stage of development. In the case of inhibition at day 2 of development a delay in the total time necessary for maturation was observed that was equal to the length of time the inhibitor was applied. Hybridization experiments with a pollen-specific cDNA probe showed that the pattern of gene expression in vitro was similar to that in vivo. However, the model system differs from natural pollen development with respect to the dehydration period, which is absent in the model system, and the synthesis of proteins. Protein synthesis of in-vitro cultured pollen differed significantly from that of pollen developing in vivo, even though pollen maturation in vitro proceeded in the same time as in vivo, and led to fully matured fertile pollen. Pollen development in vitro is thus an ideal model system for studying gene expression in relation to fertility and for experimental manipulation of microsporogenesis. 相似文献
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Background
Production of pharmaceuticals in plants provides an alternative for chemical synthesis, fermentation or natural sources. Nicotiana benthamiana is deployed at commercial scale for production of therapeutic proteins. Here the potential of this plant is explored for rapid production of precursors of artemisinin, a sesquiterpenoid compound that is used for malaria treatment.Methodology/Principal Findings
Biosynthetic genes leading to artemisinic acid, a precursor of artemisinin, were combined and expressed in N. benthamiana by agro-infiltration. The first committed precursor of artemisinin, amorpha-4,11-diene, was produced upon infiltration of a construct containing amorpha-4,11-diene synthase, accompanied by 3-hydroxy-3-methylglutaryl-CoA reductase and farnesyl diphosphate synthase. Amorpha-4,11-diene was detected both in extracts and in the headspace of the N. benthamiana leaves. When the amorphadiene oxidase CYP71AV1 was co-infiltrated with the amorphadiene-synthesizing construct, the amorpha-4,11-diene levels strongly decreased, suggesting it was oxidized. Surprisingly, no anticipated oxidation products, such as artemisinic acid, were detected upon GC-MS analysis. However, analysis of leaf extracts with a non-targeted metabolomics approach, using LC-QTOF-MS, revealed the presence of another compound, which was identified as artemisinic acid-12-β-diglucoside. This compound accumulated to 39.5 mg.kg−1 fwt. Apparently the product of the heterologous pathway that was introduced, artemisinic acid, is further metabolized efficiently by glycosyl transferases that are endogenous to N. benthamiana.Conclusion/Significance
This work shows that agroinfiltration of N. bentamiana can be used as a model to study the production of sesquiterpenoid pharmaceutical compounds. The interaction between the ectopically introduced pathway and the endogenous metabolism of the plant is discussed. 相似文献10.