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71.
Disruption of diacylglycerol kinase delta (DGKD) associated with seizures in humans and mice
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Leach NT Sun Y Michaud S Zheng Y Ligon KL Ligon AH Sander T Korf BR Lu W Harris DJ Gusella JF Maas RL Quade BJ Cole AJ Kelz MB Morton CC 《American journal of human genetics》2007,80(4):792-799
We report a female patient with a de novo balanced translocation, 46,X,t(X;2)(p11.2;q37)dn, who exhibits seizures, capillary abnormality, developmental delay, infantile hypotonia, and obesity. The 2q37 breakpoint observed in association with the seizure phenotype is of particular interest, because it lies near loci implicated in epilepsy in humans and mice. Fluorescence in situ hybridization mapping of the translocation breakpoints showed that no known genes are disrupted at Xp11.2, whereas diacylglycerol kinase delta (DGKD) is disrupted at 2q37. Expression studies in Drosophila and mouse suggest that DGKD is involved in central nervous system development and function. Electroencephalographic assessment of Dgkd mutant mice revealed abnormal epileptic discharges and electrographic seizures in three of six homozygotes. These findings implicate DGKD disruption by the t(X;2)(p11.2;q37)dn in the observed phenotype and support a more general role for DGKD in the etiology of seizures. 相似文献
72.
Särkinen TE Newman MF Maas PJ Maas H Poulsen AD Harris DJ Richardson JE Clark A Hollingsworth M Pennington RT 《Molecular phylogenetics and evolution》2007,44(3):968-980
Renealmia L.f. (Zingiberaceae) is one of the few tropical plant genera with numerous species in both Africa and South America but not in Asia. Based on phylogenetic analysis of nuclear ribosomal internal transcribed spacer (ITS) and chloroplast trnL-F DNA, Renealmia is shown to be monophyletic with high branch support. Low sequence divergence found in the two genome regions (ITS: 0-2.4%; trnL-F: 0-1.9%) suggests recent diversification within the genus. Molecular divergence age estimates give further support to the recent origin of the genus and show that Renealmia has attained its amphi-Atlantic distribution by an oceanic long-distance dispersal event from Africa to South America during the Miocene or Pliocene (15.8-2.7 My ago). Some support is found for the hypothesis that speciation in neotropical Renealmia was influenced by the Andean orogeny. Speciation has been approximately simultaneous on both sides of the Atlantic, but increased taxon sampling is required to compare the speciation rates between the New World and Old World tropics. 相似文献
73.
van Zuiden M Heijnen CJ van de Schoot R Amarouchi K Maas M Vermetten E Geuze E Kavelaars A 《PloS one》2011,6(12):e29142
Major depressive disorder (MDD) is frequently diagnosed in military personnel returning from deployment. Literature suggests that MDD is associated with a pro-inflammatory state. To the best of our knowledge, no prospective, longitudinal studies on the association between development of depressive symptomatology and cytokine production by peripheral blood leukocytes have been published. The aim of this study was to investigate whether the presence of depressive symptomatology six months after military deployment is associated with the capacity to produce cytokines, as assessed before and after deployment. 1023 military personnel were included before deployment. Depressive symptoms and LPS- and T-cell mitogen-induced production of 16 cytokines and chemokines in whole blood cultures were measured before (T0), 1 (T1), and 6 (T2) months after return from deployment. Exploratory structural equation modeling (ESEM) was used for data reduction into cytokine patterns. Multiple group latent growth modeling was used to investigate differences in the longitudinal course of cytokine production between individuals with (n = 68) and without (n = 665) depressive symptoms at T2. Individuals with depressive symptoms after deployment showed higher T-cell cytokine production before deployment. Moreover, pre-deployment T-cell cytokine production significantly predicted the presence of depressive symptomatology 6 months after return. There was an increase in T-cell cytokine production over time, but this increase was significantly smaller in individuals developing depressive symptoms. T-cell chemokine and LPS-induced innate cytokine production decreased over time and were not associated with depressive symptoms. These results indicate that increased T-cell mitogen-induced cytokine production before deployment may be a vulnerability factor for development of depressive symptomatology in response to deployment to a combat-zone. In addition, deployment to a combat-zone affects the capacity of T-cells and monocytes to produce cytokines and chemokines until at least 6 months after return. 相似文献
74.
Replacement of primary chicken embryonic fibroblasts (CEF) by the DF-1 cell line for detection of avian leucosis viruses. 总被引:2,自引:0,他引:2
International regulations prescribe that the absence of avian leucosis viruses (ALV) in avian live virus vaccines has to be demonstrated. Primary chicken embryo fibroblasts (CEF) from special SPF chicken lines are normally used for detection of ALV. The suitability of the DF-1 cell line for ALV-detection, as alternative for primary CEF, was studied in three types of experiments: (1) in titration experiments without cell passage, (2) in experiments with passages in cell cultures according to European Pharmacopoeia requirements, and (3) in experiments with commercial live avian vaccines that had been spiked with known amounts of ALV. In all tests the sensitivity of ALV-A and ALV-J detections on DF-1 cells was at least as high as on primary CEF. The sensitivity of ALV-B detection was always superior when DF-1 cells were used. ALV were detected earlier in all comparative tests when DF-1 cells were used. ALV-A, ALV-B and ALV-J all induced CPE on DF-1 cells, whereas no clear CPE was seen on CEF-cells. For reasons of sensitivity, standardisation as well as reduction of animal use, the data support the use of DF-1 cells to monitor absence of ALV in vaccine virus seed lots or finished products. 相似文献
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78.
van der Kuyl AC Ph Ballasina DL Dekker JT Maas J Willemsen RE Goudsmit J 《Molecular phylogenetics and evolution》2002,22(2):174-183
To test phylogenetic relationships within the genus Testudo (Testudines: Testudinidae), we have sequenced a fragment of the mitochondrial (mt) 12S rRNA gene of 98 tortoise specimens belonging to the genera Testudo, Indotestudo, and Geochelone. Maximum likelihood and neighbor-joining methods identify two main clades of Mediterranean tortoises, one composed of the species Testudo graeca, Testudo marginata, and Testudo kleinmanni and a second of Testudo hermanni, Testudo horsfieldii, and Indotestudo elongata. The first clade, but not the second, was also supported by maximum parsimony analysis. Together with the genus Geochelone, a star-like radiation of these clades was suggested, as a sister-group relationship between the two Testudo clades could not be confirmed. The intraspecies genetic variation was examined by sequencing the mt 12S rRNA fragment from 28 specimens of T. graeca and 49 specimens of T. hermanni from various geographic locations. Haplotype diversity was found to be significantly larger in T. graeca compared with T. hermanni, suggestive of reduced genetic diversity in the latter species, perhaps due to Pleistocene glaciations affecting northern and middle Europe or other sources of lineage reduction. No ancient mt 12S rRNA gene haplotypes were identified in T. graeca and/or T. hermanni originating from islands in the Mediterranean Sea, suggesting that these islands harbor tortoise populations introduced from the European and African mainland. 相似文献
79.
Information on the effects of elevated ammonia on invertebrates in general, and polar Mollusks in particular, is scant. Questions of ammonia sensitivity are interesting for several reasons, particularly since predicted global change scenarios include increasing anthropogenic nitrogen and toxic ammonia. Furthermore, polar zooplankton species are often lipid-rich, and authors have speculated that there is a linkage between elevated levels of lipids/trimethylamine oxide and enhanced ammonia tolerance. In the present study, we sought to examine ammonia tolerance and effects of elevated exogenous ammonia on several key aspects of the physiology and biochemistry of the pteropod mollusk, Clione limacina antarctica. We determined that the 96-h LC50 value for this species is 7.465?mM total ammonia (Upper 95% CL?=?8.498?mM and Lower 95% CL?=?6.557?mM) or 0.51?mg/L as unionized ammonia (NH3) (at a pH of 7.756). While comparative data for mollusks are limited, this value is at the lower end of reported values for other species. When the effects of lower ammonia concentrations (0.07?mM total ammonia) on oxygen consumption and ammonia excretion rates were examined, no effects were noted. However, total ammonia levels as low as 0.1?mM (or 0.007?mg/l NH3) elevated the activity of the ammonia detoxification enzyme glutamine synthetase by approximately 1.5-fold. The values for LC50 and observable effects on biochemistry for this one species are very close to permissible marine ammonia concentrations, indicating a need to more broadly determine the sensitivity of zooplankton to potential elevated ammonia levels in polar regions. 相似文献
80.
De Groot GA During HJ Ansell SW Schneider H Bremer P Wubs ER Maas JW Korpelainen H Erkens RH 《Annals of botany》2012,109(5):965-978