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Miguel Mies M. A. Van Sluys C. J. Metcalfe P. Y. G. Sumida 《Symbiosis (Philadelphia, Pa.)》2017,72(1):13-22
Dinoflagellates in the genus Symbiodinium (zooxanthellae) provide the photosynthesis that sustains the majority of primary production in coral reefs. They occur symbiotically with several phyla, including mollusks such as giant clams (Tridacna spp.). This mutualistic association is obligatory for the giant clams, but the exact point in which this symbiosis is established and the main translocated photosynthate are unknown. In this study, we tracked the expression of specific genes for symbiosis and glycerol synthesis during a time course experiment. Giant clam larvae were raised until 75 h post-fertilization and then infected with cultured isolates of Symbiodinium clade A3. Expression of symbiosis-specific and housekeeping genes was monitored at four time points. The expression of H+-ATPase, a symbiosis-specific gene in Symbiodinium, was observed at 24 h after symbiont acquisition by the clam larvae. The expression of an enzyme responsible for glycerol synthesis was also observed. Together, these results show that the symbiotic relationship was already in place 24 h after Symbiodinium acquisition, during veliger larval stage. This is the first report using a molecular symbiosis-specific marker that supports symbiotic activity between Symbiodinium and a metazoan larva of an organism that acquires symbionts horizontally. From the expression of the glycerol-synthesizing gene, it was qualitatively determined that Symbiodinium cells may produce glycerol regardless of whether they are free-living or in symbiosis. 相似文献
13.
Mies M. Güth A. Z. Tenório A. A. Banha T. N. S. Waters L. G. Polito P. S. Taniguchi S. Bícego M. C. Sumida P. Y. G. 《Coral reefs (Online)》2018,37(3):677-689
Coral Reefs - Many species of reef-building corals are mixotrophic, relying on both photoautotrophy performed by their dinoflagellate symbionts and heterotrophy from consumption of zooplankton.... 相似文献
14.
Leban J Kralik M Mies J Baumgartner R Gassen M Tasler S 《Bioorganic & medicinal chemistry letters》2006,16(2):267-270
A previously discovered DHODH inhibitor series was further improved by replacing the cyclopentene ring by aromatic heterocycles. Different isomers of these compounds were prepared by the directed ortho-metallation procedure. The compounds are more active than the corresponding cyclopentene analogs and show potent effects on PBMC's proliferation. 相似文献
15.
While the naturally occurring reducing agents glutathione (GSH) and ascorbate (H2A) alone are ineffective at reducing iron(III) sequestered by the siderophore ferrioxamine B, the addition of an iron(II)
chelator, sulfonated bathophenanthroline (BPDS), facilitates reduction by either reducing agent. A mechanism is described
in which a ternary complex is formed between ferrioxamine B and BPDS in a rapidly established pre-equilibrium step, which
is followed by rate limiting reduction of the ternary complex by glutathione or ascorbate. Spectral, thermodynamic, and kinetic
evidence are given for ternary complex formation. Ascorbate was found to be slightly more efficient at reducing the ternary
complex than glutathione (k4=2.1×10−3 M−1 s−1 and k4=6.3×10−4 M−1 s−1, respectively) at pH 7. Reduction is followed by a rapid ligand exchange step where iron is released from ferrioxamine B
to form tris-(BPDS)iron(II). The implications of these results for siderophore mediated iron transport and release are discussed. 相似文献
16.
Nico J. Leschot Jaak J. de Nef Mies J. Becker-Bloemkolk Marianne Verjaal Paul F. Wiesenhaan 《Human genetics》1978,43(3):333-336
Summary The three main features of Meckel syndrome are encephalocele, polycystic kidneys, and polydactyly. Prenatal diagnosis of a fetus with Meckel syndrome was made in the 16th week of gestation by means of amniotic fluid alpha1 fetoprotein estimation. The indication for amniocentesis was a previous child with an occipital meningocele and polycystic kidneys. Interpretation of the alpha1-fetoprotein value (240 g/ml) was difficult due to fetal blood contamination. Prenatal diagnosis is indicated in any pregnancy following the birth of a child with only two major symptoms of Meckel syndrome. 相似文献
17.
It has been proposed that NAD depletion resulting from excessive activation of poly(ADP-ribose) polymerase is responsible for secondary energy failure after transient cerebral ischemia. However, this hypothesis has never been verified by measurement of ATP and NAD levels in the same tissue sample. In this study, we therefore investigated the effect of transient focal cerebral ischemia on the temporal profiles of changes in the levels of energy metabolites and NAD. Ischemia was induced in mice by occluding the left middle cerebral artery using the intraluminal filament technique. Animals were subjected to 1-h ischemia, followed by 0, 1, 3, 6, or 24 h of reperfusion. During ischemia, ATP levels, total adenylate pool, and adenylate energy charge dropped to approximately 20, 50, and 40% of control, respectively, whereas NAD levels remained close to control. Energy state recovered transiently, peaking at 3 h of recovery (ATP levels and total adenylate pool recovered to 78 and 81% of control). In animals subjected to reperfusion of varying duration, the extent of ATP depletion was clearly more pronounced than that of NAD. The results imply that depletion of NAD pools did not play a major role in secondary disturbances of energy-producing metabolism after transient focal cerebral ischemia. Changes in ATP levels were closely related to changes in total adenylate pool (p<0.001). The high energy charge after 6 h of reperfusion (0.90 versus a control value of 0.93) and the close relationship between the decline of ATP and total adenylate pool suggest that degradation or a washout of adenylates (owing to leaky membranes) rather than a mismatch between energy production and consumption is the main causative factor contributing to the secondary energy failure observed after prolonged recovery. 相似文献
18.
The isolation and structural elucidation of a new naphthylisoquinoline alkaloid, 8-O-methyldioncophyllinol B, from Triphyophyllum peltatum (Hutch. et Dalz.) Airy Shaw (Dioncophyllaceae) is described, together with the revised structures of other 'B-type' compounds previously misidentified as dioncophylline D, dioncophyllinol D, and 8-O-methyldioncophylline D. All of the presently described structures are 7,6'-coupled and thus have to be addressed as 'B-type' naphthylisoquinoline alkaloids. This is in contrast to the initially defined 'D-type' structures, which are 7,8'-coupled as confirmed by a total synthesis of dioncophylline D. Some of these natural and synthetic naphthylisoquinolines were found to display good in vitro antiplasmodial activities. 相似文献
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Marília D’Elboux Guimar?es Brescia Paulo Celso Bosco Massarollo Ernesto Sasaki Imakuma Sérgio Mies 《PloS one》2015,10(6)
Background
This randomized prospective clinical trial compared the hepatic venous outflow drainage and renal function after conventional with venovenous bypass (n = 15) or piggyback (n = 17) liver transplantation.Methods
Free hepatic vein pressure (FHVP) and central venous pressure (CVP) measurements were performed after graft reperfusion. Postoperative serum creatinine (Cr) was measured daily on the first week and on the 14th, 21st and 28th postoperative days (PO). The prevalence of acute renal failure (ARF) up to the 28th PO was analyzed by RIFLE-AKIN criteria. A Generalized Estimating Equation (GEE) approach was used for comparison of longitudinal measurements of renal function.Results
FHVP-CVP gradient > 3 mm Hg was observed in 26.7% (4/15) of the patients in the conventional group and in 17.6% (3/17) in the piggyback group (p = 0.68). Median FHVP-CVP gradient was 2 mm Hg (0–8 mmHg) vs. 3 mm Hg (0–7 mm Hg) in conventional and piggyback groups, respectively (p = 0.73). There is no statistically significant difference between the conventional (1/15) and the piggyback (2/17) groups regarding massive ascites development (p = 1.00). GEE estimated marginal mean for Cr was significantly higher in conventional than in piggyback group (2.14 ± 0.26 vs. 1.47 ± 0.15 mg/dL; p = 0.02). The conventional method presented a higher prevalence of severe ARF during the first 28 PO days (OR = 3.207; 95% CI, 1.010 to 10.179; p = 0.048).Conclusion
Patients submitted to liver transplantation using conventional or piggyback methods present similar results regarding venous outflow drainage of the graft. Conventional with venovenous bypass technique significantly increases the harm of postoperative renal dysfunction.Trial Registration
ClinicalTrials.gov https://clinicaltrials.gov/ct2/show/NCT01707810 相似文献20.
Next generation of elevated [CO2] experiments with crops: a critical investment for feeding the future world 总被引:1,自引:0,他引:1
Ainsworth EA Beier C Calfapietra C Ceulemans R Durand-Tardif M Farquhar GD Godbold DL Hendrey GR Hickler T Kaduk J Karnosky DF Kimball BA Körner C Koornneef M Lafarge T Leakey AD Lewin KF Long SP Manderscheid R McNeil DL Mies TA Miglietta F Morgan JA Nagy J Norby RJ Norton RM Percy KE Rogers A Soussana JF Stitt M Weigel HJ White JW 《Plant, cell & environment》2008,31(9):1317-1324
A rising global population and demand for protein-rich diets are increasing pressure to maximize agricultural productivity. Rising atmospheric [CO2 ] is altering global temperature and precipitation patterns, which challenges agricultural productivity. While rising [CO2 ] provides a unique opportunity to increase the productivity of C3 crops, average yield stimulation observed to date is well below potential gains. Thus, there is room for improving productivity. However, only a fraction of available germplasm of crops has been tested for CO2 responsiveness. Yield is a complex phenotypic trait determined by the interactions of a genotype with the environment. Selection of promising genotypes and characterization of response mechanisms will only be effective if crop improvement and systems biology approaches are closely linked to production environments, that is, on the farm within major growing regions. Free air CO2 enrichment (FACE) experiments can provide the platform upon which to conduct genetic screening and elucidate the inheritance and mechanisms that underlie genotypic differences in productivity under elevated [CO2 ]. We propose a new generation of large-scale, low-cost per unit area FACE experiments to identify the most CO2 -responsive genotypes and provide starting lines for future breeding programmes. This is necessary if we are to realize the potential for yield gains in the future. 相似文献