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排序方式: 共有1704条查询结果,搜索用时 109 毫秒
91.
Louise Robertson Travis Featherby Stuart Howell James Hughes Paul Thomas 《Genes, Brain & Behavior》2019,18(5)
Mutations in proline‐rich transmembrane protein 2 (PRRT2) cause a range of episodic disorders that include paroxysmal kinesigenic dyskinesia and benign familial infantile epilepsy. Mutations are generally loss of function and include the c649dupC frameshifting mutation that is present in around 80% of affected individuals. To investigate how Prrt2 loss of function mutations causes disease, we performed a phenotypic investigation of a transgenic Prrt2 knockout (Prrt2 KO) mouse. We observed spontaneous paroxysmal episodes with behavioural features of both seizure and movement disorders, as well as unexplained deaths in KO and HET animals. KO mice showed spatial learning deficits in the Morris water maze, as well as gait abnormalities in the quantitative Digigait analysis; both of which may be representative of the more severe phenotypes experienced by homozygous patients. These findings extend the described phenotypes of Prrt2 mutant mice, further confirming their utility for in vivo investigation of the role of Prrt2 mutations in episodic diseases. 相似文献
92.
Genome sequence of Babesia bovis and comparative analysis of apicomplexan hemoprotozoa 总被引:1,自引:0,他引:1
Brayton KA Lau AO Herndon DR Hannick L Kappmeyer LS Berens SJ Bidwell SL Brown WC Crabtree J Fadrosh D Feldblum T Forberger HA Haas BJ Howell JM Khouri H Koo H Mann DJ Norimine J Paulsen IT Radune D Ren Q Smith RK Suarez CE White O Wortman JR Knowles DP McElwain TF Nene VM 《PLoS pathogens》2007,3(10):1401-1413
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95.
Venter GJ Groenewald DM Paweska JT Venter EH Howell PG 《Medical and veterinary entomology》1999,13(4):393-400
Equine encephalosis virus (EEV) was recognized and described in the Republic of South Africa in 1967 and subsequent serological studies have shown this orbivirus to be both widespread and prevalent in southern Africa. In the present study it was shown that wild-caught Culicoides (Avaritia) imicola Kieffer (Diptera: Ceratopogonidae) can become infected with and permit the replication of the Bryanston serotype of EEV following membrane-feeding on infective blood containing 5.0 log10 plaque-forming-units (PFU)/ml. The mean prevalence of Bryanston virus infection in C. imicola after 10 days extrinsic incubation at 23.5 degrees C was 22.3% (23/103). The mean infectivity of Bryanston virus in the infected C. imicola increased from 1.3 log10 PFU/midge, in insects assayed immediately after feeding on the blood-virus mixture, to 2.6 log10 PFU/midge in insects assayed after incubation. The virus concentration in individual C. imicola infected with the Bryanston serotype of EEV ranged from 0.7 to 3.6 log10 PFU/midge. Bryanston virus titres higher than 2.5 log10 TCID50, found in individual C. imicola, suggest that this species may be able to transmit this virus to susceptible hosts. Prevalence of virus infection in C. imicola was determined by PFU and microtitration assays on both BHK and Vero cells and confirmation of the Bryanston serotype of EEV was determined by plaque inhibition. No virus replication could be demonstrated in 102 C. nivosus tested after the incubation period, suggesting that not all Culicoides species are equally susceptible to Bryanston virus infection. Other Culicoides species that survived the incubation period and that were negative for the presence of Bryanston virus were C. pycnostictus (42), C. leucostictus (7), C. magnus (2), C. bolitinos (1) and C. bedfordi (1). 相似文献
96.
Strasser V Fasching D Hauser C Mayer H Bock HH Hiesberger T Herz J Weeber EJ Sweatt JD Pramatarova A Howell B Schneider WJ Nimpf J 《Molecular and cellular biology》2004,24(3):1378-1386
The Reelin signaling cascade plays a crucial role in the correct positioning of neurons during embryonic brain development. Reelin binding to apolipoprotein E receptor 2 (ApoER2) and very-low-density-lipoprotein receptor (VLDLR) leads to phosphorylation of disabled 1 (Dab1), an adaptor protein which associates with the intracellular domains of both receptors. Coreceptors for Reelin have been postulated to be necessary for Dab1 phosphorylation. We show that bivalent agents specifically binding to ApoER2 or VLDLR are sufficient to mimic the Reelin signal. These agents induce Dab1 phosphorylation, activate members of the Src family of nonreceptor tyrosine kinases, modulate protein kinase B/Akt phosphorylation, and increase long-term potentiation in hippocampal slices. Induced dimerization of Dab1 in HEK293 cells leads to its phosphorylation even in the absence of Reelin receptors. The mechanism for and the sites of these phosphorylations are identical to those effected by Reelin in primary neurons. These results suggest that binding of Reelin, which exists as a homodimer in vivo, to ApoER2 and VLDLR induces clustering of ApoER2 and VLDLR. As a consequence, Dab1 becomes dimerized or oligomerized on the cytosolic side of the plasma membrane, constituting the active substrate for the kinase; this process seems to be sufficient to transmit the signal and does not appear to require any coreceptor. 相似文献
97.
98.
Inomata Y Arai Y Yamakoshi T Scott Howell F 《Journal of inorganic biochemistry》2004,98(12):2149-2159
Six cadmium(II) halide complexes with dl-piperidine-2-carboxylic acid (DL-Hpipe-2), dl-piperidine-3-carboxylic acid (DL-Hpipe-3), and piperidine-4-carboxylic acid (Hpipe-4), have been prepared and characterized by means of IR and Raman spectra and thermal analysis. The crystal structures of [CdCl2(DL-Hpipe-2)(H2O)], [CdBr2(DL-Hpipe-3)], and [CdCl2(Hpipe-4)] have been determined by X-ray diffraction. These three complexes have one-dimensional polymer structures bridged by halide atoms. The crystal of [CdCl2(DL-Hpipe-2)(H2O)] is orthorhombic with the space group Pca2(1). The cadmium atom is in an octahedral geometry, ligated by a carboxyl oxygen atom, two bridging chlorine atoms, a terminal chlorine atom, a water molecule and a carboxyl oxygen atom of a neighboring molecule. The carboxyl oxygen atoms of DL-Hpipe-2 are coordinated to two cadmium atoms. The unit cell consists of two types of one-dimensional polymer structures: [CdCl2(D-Hpipe-2)(H2O)] and [CdCl2(L-Hpipe-2)(H2O)]. Therefore, it is better to write [CdCl2(DL-Hpipe-2)(H2O)] as [CdCl2(D-Hpipe-2)(H2O)][CdCl2(L-Hpipe-2)(H2O)]. The crystal structure of [CdBr2(DL-Hpipe-3)] is monoclinic with space group P2(1). The cadmium atom is in a distorted octahedral geometry ligated by two carboxyl oxygen atoms and four bridging bromine atoms. This complex consists of either D-Hpipe-3 or L-Hpipe-3. Therefore [CdBr2(DL-Hpipe-3)] is written as [CdBr2(D or L-Hpipe-3)]. The crystal of [CdCl2(Hpipe-4)] is monoclinic with space group P2(1)/n. The structure is similar to that of [CdBr2(D or L-Hpipe-3)]. 相似文献
99.
Thyfault JP Kraus RM Hickner RC Howell AW Wolfe RR Dohm GL 《American journal of physiology. Endocrinology and metabolism》2004,287(6):E1076-E1081
Skeletal muscle from extremely obese individuals exhibits decreased lipid oxidation compared with muscle from lean controls. It is unknown whether this effect is observed in vivo or whether the phenotype is preserved after massive weight loss. The objective of this study was to compare free fatty acid (FFA) oxidation during rest and exercise in female subjects who were either lean [n = 7; body mass index (BMI) = 22.6 +/- 2.2 kg/m(2)] or extremely obese (n = 10; BMI = 40.8 +/- 5.4 kg/m(2)) or postgastric bypass patients who had lost >45 kg (weight reduced) (n = 6; BMI = 33.7 +/- 9.9 kg/m(2)) with the use of tracer ([(13)C]palmitate and [(14)C]acetate) methodology and indirect calorimetry. The lean group oxidized significantly more plasma FFA, as measured by percent fatty acid uptake oxidized, than the extremely obese or weight-reduced group during rest (66.6 +/- 14.9 vs. 41.5 +/- 16.4 vs. 39.9 +/- 15.3%) and exercise (86.3 +/- 11.9 vs. 56.3 +/- 22.1 vs. 57.3 +/- 20.3%, respectively). BMI significantly correlated with percent uptake oxidized during both rest (r = -0.455) and exercise (r = -0.459). In conclusion, extremely obese women and weight-reduced women both possess inherent defects in plasma FFA oxidation, which may play a role in massive weight gain and associated comorbidities. 相似文献
100.
Predicting function from structure: 3D structure studies of the mammalian Golgi complex 总被引:6,自引:0,他引:6
3D electron tomography studies of the structure of the mammalian Golgi complex have led to four functional predictions (1). The sorting and exit site from the Golgi comprises two or three distinct trans-cisternae (2). The docking of vesicular-tubular clusters at the cis-face and the fragmentation of trans-cisternae are coordinated (3). The mechanisms of transport through, and exit from, the Golgi vary with physiological state, and in different cells and tissues (4). Specialized trans-ER functions in the delivery of ceramide to sphingomyelin synthase in the trans-Golgi membrane, for the regulated sorting via sphingolipid-cholesterol-rich domains. These structure-based predictions can now be tested using a variety of powerful cell and molecular tools. 相似文献