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101.
Allantoate hydrolysis by allantoate amidohydrolase 总被引:4,自引:0,他引:4
C van der Drift F E de Windt G D Vogels 《Archives of biochemistry and biophysics》1970,136(1):273-279
102.
Jelke J. Fros Corinne Geertsema Chantal B. Vogels Peter P. Roosjen Anna-Bella Failloux Just M. Vlak Constantianus J. Koenraadt Willem Takken Gorben P. Pijlman 《PLoS neglected tropical diseases》2015,9(7)
Background
West Nile virus (WNV) is a highly pathogenic flavivirus transmitted by Culex spp. mosquitoes. In North America (NA), lineage 1 WNV caused the largest outbreak of neuroinvasive disease to date, while a novel pathogenic lineage 2 strain circulates in southern Europe. To estimate WNV lineage 2 epidemic potential it is paramount to know if mosquitoes from currently WNV-free areas can support further spread of this epidemic.Methodology/Principal Findings
We assessed WNV vector competence of Culex pipiens mosquitoes originating from north-western Europe (NWE) in direct comparison with those from NA. We exposed mosquitoes to infectious blood meals of lineage 1 or 2 WNV and determined the infection and transmission rates. We explored reasons for vector competence differences by comparing intrathoracic injection versus blood meal infection, and we investigated the influence of temperature. We found that NWE mosquitoes are highly competent for both WNV lineages, with transmission rates up to 25%. Compared to NA mosquitoes, transmission rates for lineage 2 WNV were significantly elevated in NWE mosquitoes due to better virus dissemination from the midgut and a shorter extrinsic incubation time. WNV infection rates further increased with temperature increase.Conclusions/Significance
Our study provides experimental evidence to indicate markedly different risk levels between both continents for lineage 2 WNV transmission and suggests a degree of genotype-genotype specificity in the interaction between virus and vector. Our experiments with varying temperatures explain the current localized WNV activity in southern Europe, yet imply further epidemic spread throughout NWE during periods with favourable climatic conditions. This emphasizes the need for intensified surveillance of virus activity in current WNV disease-free regions and warrants increased awareness in clinics throughout Europe. 相似文献103.
104.
At least at the level of inferior temporal cortex,the stereo correspondence problem is solved 总被引:3,自引:0,他引:3
Stereoscopic vision requires the correspondence problem to be solved, i.e., discarding "false" matches between images of the two eyes, while keeping correct ones. To advance our understanding of the underlying neuronal mechanisms, we compared single neuron responses to correlated and anticorrelated random dot stereograms (RDSs). Inferior temporal neurons, which respond selectively to disparity-defined three-dimensional shapes, showed robust selectivity for correlated RDSs portraying concave or convex surfaces, but unlike neurons in areas V1, MT/V5, and MST, were not selective for anticorrelated RDSs. These results show that the correspondence problem is solved at least in far extrastriate cortex, as it is in the monkey's perception. 相似文献
105.
Stephen M. Kissler Joseph R. Fauver Christina Mack Scott W. Olesen Caroline Tai Kristin Y. Shiue Chaney C. Kalinich Sarah Jednak Isabel M. Ott Chantal B. F. Vogels Jay Wohlgemuth James Weisberger John DiFiori Deverick J. Anderson Jimmie Mancell David D. Ho Nathan D. Grubaugh Yonatan H. Grad 《PLoS biology》2021,19(7)
106.
Lara Heij Marieke Niesters Maarten Swartjes Elske Hoitsma Marjolein Drent Ann Dunne Jan C Grutters Oscar Vogels Michael Brines Anthony Cerami Albert Dahan 《Molecular medicine (Cambridge, Mass.)》2012,18(1):1430-1436
ARA 290 (a peptide designed to activate the innate repair receptor that arrests injury and initiates cytoprotection, antiinflammation and healing) reduces allodynia in preclinical neuropathy models. We studied the safety and efficacy of ARA 290 to reduce symptoms of small fiber neuropathy (SFN) in patients with sarcoidosis. A total of 22 patients diagnosed with sarcoidosis and symptoms of SFN were enrolled in a double-blind, placebo-controlled exploratory trial consisting of three times weekly intravenous dosing of ARA 290 (2 mg; n = 12) or placebo (n = 10) for 4 wks. Inclusion criteria were a diagnosis of neuropathy and a spontaneous pain score of ≥5 (Brief Pain Inventory [BPI]). Endpoints assessed were changes in pain intensity and the small fiber neuropathy screening list (SFNSL) score, quality of life (SF-36), depressive symptoms (Inventory of Depressive Symptomatology [IDS]) and fatigue (Fatigue Assessment Scale [FAS]). No safety concerns were raised by clinical or laboratory assessments. The ARA 290 group showed significant (p < 0.05) improvement at wk 4 in SFNSL score compared with placebo (Δ −11.5 ± 3.04 versus Δ −2.9 ± 3.34 [standard error of the mean]). Additionally, the ARA 290 group showed a significant change from baseline in the pain and physical functioning dimensions of the SF-36 (Δ −23.4 ± 5.5 and Δ −14.6 ± 3.9, respectively). The mean BPI and FAS scores improved significantly but equivalently in both patient groups. No change was observed in the IDS. ARA 290 appears to be safe in patients with sarcoidosis and can reduce neuropathic symptoms. 相似文献
107.
J. J. P. Baars H. J. M. Op den Camp J. W. G. Paalman V. Mikeš C. van der Drift L. J. L. D. Van Griensven G. D. Vogels 《Current microbiology》1995,31(2):108-113
Agaricus bisporus glutamine synthetase, a key enzyme in nitrogen metabolism, was purified to apparent homogeneity. The native enzyme appeared to be a GS-II type enzyme. It has a molecular weight of 325 kDa and consists of eight 46-kDa subunits. Its pI was found at 4.9. Optimal activity was found at 30°C. The enzyme had low thermostability. Stability declined rapidly at temperatures above 20°C. The enzyme exhibits a K
m for glutamate, ammonium, and ATP of 22mm, 0.16mm and 1.25mm respectively in the biosynthetic reaction, with optimal activity at pH 7. The enzyme is slightly inhibited by 10mm concentrations of l-alanine, l-histidine, l-tryptophan, anthranilic acid, and 5-AMP and was strongly inhibited by methionine sulfoximine and phosphinothricine. For the transferase reaction K
i-values were 890 m and 240 m for methionine sulfoximine and phosphinothricine respectively. For the biosynthetic reaction K
i was 17 m for both methionine sulfoximine and phosphinothricine. 相似文献
108.
Coenzyme F390 synthetase from Methanobacterium thermoautotrophicum Marburg belongs to the superfamily of adenylate-forming enzymes.
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P Vermeij R J van der Steen J T Keltjens G D Vogels T Leisinger 《Journal of bacteriology》1996,178(2):505-510
Depending on the reduction-oxidation state of the cell, some methanogenic bacteria synthesize or hydrolyze 8-hydroxyadenylylated coenzyme F420 (coenzyme F390). These two reactions are catalyzed by coenzyme F390 synthetase and hydrolase, respectively. To gain more insight into the mechanism of the former reaction, coenzyme F390 synthetase from Methanobacterium thermoautotrophicum Marburg was purified 89-fold from cell extract to a specific activity of 0.75 mumol.min-1.mg of protein-1. The monomeric enzyme consisted of a polypeptide with an apparent molecular mass of 41 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. ftsA, the gene encoding coenzyme F390 synthetase, was cloned and sequenced. It encoded a protein of 377 amino acids with a predicted M(r) of 43,280. FtsA was found to be similar to domains found in the superfamily of peptide synthetases and adenylate-forming enzymes. FtsA was most similar to gramicidin S synthetase II (67% similarity in a 227-amino-acid region) and sigma-(L-alpha-aminoadipyl)-L-cysteine-D-valine synthetase (57% similarity in a 193-amino-acid region). Coenzyme F390 synthetase, however, holds an exceptional position in the superfamily of adenylate-forming enzymes in that it does not activate a carboxyl group of an amino or hydroxy acid but an aromatic hydroxyl group of coenzyme F420. 相似文献
109.
110.
Johan J. A. van Bruggen Kor B. Zwart Renée M. van Assema Claudius K. Stumm Godfried G. Vogels 《Archives of microbiology》1984,139(1):1-7
The Gram-positive methanogenic endosymbiont of the sapropelic ciliateMetopus striatus was isolated and identified asMethanobacterium formicicum. In the ciliate cell the methanogens are in close association with microbody-like organelles. No mitochondria could be detected. The nature of the microbodies and the physiological background of the observed association are discussed. 相似文献