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81.
82.
在麻醉的32只猫记录了电刺激颌下腺神经支引起的上涎核平均场电位和单位放电。逆行电刺激颌下腺神经支引起的上涎核平均场电位分布在同侧脑干背面闩部头端5.5—8mm处,与过去的组织学结果大致符合。用微电极在上涎核记录了68个对刺激颌下腺神经支有反应的单位,其中33个单位作了碰撞试验。有9个单位符合逆向反应标准,它们是真正的颌下腺节前神经元,逆行反应的潜伏期为14.4±2.5ms,其轴突传导速度为2.9±0.1m/s。其他不符合逆向反应标准的单位,对刺激颌下腺神经支仍能发生反应,估计多为中间神经元。在一部分单位观察了电刺激舌神经或味觉刺激舌引起的反应。根据这些观察对上涎核内存在复杂神经元回路的可能性作了讨论。 相似文献
83.
Irena Trbojević-Akmačić Frano Vučković Marija Vilaj Andrea Skelin Lennart C. Karssen Jasminka Krištić Julija Jurić Ana Momčilović Jelena Šimunović Massimo Mangino Manuela De Gregori Maurizio Marchesini Concetta Dagostino Jerko Štambuk Mislav Novokmet Richard Rauck Yurii S. Aulchenko Dragan Primorac Gordan Lauc 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(10):2124-2133
Background
Low back pain (LBP) is the symptom of a group of syndromes with heterogeneous underlying mechanisms and molecular pathologies, making treatment selection and patient prognosis very challenging. Moreover, symptoms and prognosis of LBP are influenced by age, gender, occupation, habits, and psychological factors. LBP may be characterized by an underlying inflammatory process. Previous studies indicated a connection between inflammatory response and total plasma N-glycosylation. We wanted to identify potential changes in total plasma N-glycosylation pattern connected with chronic low back pain (CLBP), which could give an insight into the pathogenic mechanisms of the disease.Methods
Plasma samples of 1128 CLBP patients and 760 healthy controls were collected in clinical centers in Italy, Belgium and Croatia and used for N-glycosylation profiling by hydrophilic interaction ultra-performance liquid chromatography (HILIC-UPLC) after N-glycans release, fluorescent labeling and clean-up. Observed N-glycosylation profiles have been compared with a cohort of 126 patients with acute inflammation that underwent abdominal surgery.Results
We have found a statistically significant increase in the relative amount of high-branched (tri-antennary and tetra-antennary) N-glycan structures on CLBP patients' plasma glycoproteins compared to healthy controls. Furthermore, relative amounts of disialylated and trisialylated glycan structures were increased, while high-mannose and glycans containing bisecting N-acetylglucosamine decreased in CLBP.Conclusions
Observed changes in CLBP on the plasma N-glycome level are consistent with N-glycosylation changes usually seen in chronic inflammation.General significance
To our knowledge, this is a first large clinical study on CLBP patients and plasma N-glycome providing a new glycomics perspective on potential disease pathology. 相似文献84.
85.
A novel nuclear export signal and a REF interaction domain both promote mRNA export by the Epstein-Barr virus EB2 protein 总被引:2,自引:0,他引:2
Hiriart E Farjot G Gruffat H Nguyen MV Sergeant A Manet E 《The Journal of biological chemistry》2003,278(1):335-342
A striking characteristic of mRNA export factors is that they shuttle continuously between the cytoplasm and the nucleus. This shuttling is mediated by specific factors interacting with peptide motifs called nuclear export signals (NES) and nuclear localization signals. We have identified a novel CRM-1-independent transferable NES and two nuclear localization signals in the Epstein-Barr virus mRNA export factor EB2 (also called BMLF1, Mta, or SM) localized at the N terminus of the protein between amino acids 61 and 146. We have also found that a previously described double NES (amino acids 213-236) does not mediate the nuclear shuttling of EB2, but is an interaction domain with the cellular export factor REF in vitro. This newly characterized REF interaction domain is essential for EB2-mediated mRNA export. Accordingly, in vivo, EB2 is found in complexes containing REF as well as the cellular factor TAP. However, these interactions are RNase-sensitive, suggesting that the RNA is an essential component of these complexes. 相似文献
86.
Van VQ Darwiche J Raymond M Lesage S Bouguermouh S Rubio M Sarfati M 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(8):5204-5208
Peripheral CD103(+)Foxp3(+) regulatory T cells (Tregs) can develop both from conventional naive T cells upon cognate Ag delivery under tolerogenic conditions and from thymic-derived, expanded/differentiated natural Tregs. We here show that CD47 expression, a marker of self on hematopoietic cells, selectively regulated CD103(+)Foxp3(+) Treg homeostasis at the steady state. First, the proportion of effector/memory-like (CD44(high)CD62L(low)) CD103(+)Foxp3(+) Tregs rapidly augmented with age in CD47-deficient mice (CD47(-/-)) as compared with age-matched control littermates. Yet, the percentage of quiescent (CD44(low)CD62L(high)) CD103(-)Foxp3(+) Tregs remained stable. Second, the increased proliferation rate (BrdU incorporation) observed within the CD47(-/-)Foxp3(+) Treg subpopulation was restricted to those Tregs expressing CD103. Third, CD47(-/-) Tregs maintained a normal suppressive function in vitro and in vivo and their increased proportion in old mice led to a decline of Ag-specific T cell responses. Thus, sustained CD47 expression throughout life is critical to avoid an excessive expansion of CD103(+) Tregs that may overwhelmingly inhibit Ag-specific T cell responses. 相似文献
87.
T cell receptor-beta mRNA splicing: regulation of unusual splicing intermediates. 总被引:7,自引:3,他引:7
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L Qian L Theodor M Carter M N Vu A W Sasaki M F Wilkinson 《Molecular and cellular biology》1993,13(3):1686-1696
88.
Khanh Dang Vu S. Yan R.D. Tyagi J.R. Valéro R.Y. Surampalli 《Bioresource technology》2009,100(21):5260-5269
Induced production of chitinase during bioconversion of starch industry wastewater (SIW) to Bacillus thuringiensis var. kurstaki HD-1 (Btk) based biopesticides was studied in shake flask as well as in computer-controlled fermentors. SIW was fortified with different concentrations (0%; 0.05%; 0.1%; 0.2%; 0.3% w/v) of colloidal chitin and its consequences were ascertained in terms of Btk growth (total cell count and viable spore count), chitinase, protease and amylase activities and entomotoxicity. At optimum concentration of 0.2% w/v colloidal chitin, the entomotoxicity of fermented broth and suspended pellet was enhanced from 12.4 × 109 (without chitin) to 14.4 × 109 SBU/L and from 18.2 × 109 (without chitin) to 25.1 × 109 SBU/L, respectively. Further, experiments were conducted for Btk growth in a computer-controlled 15 L bioreactor using SIW as a raw material with (0.2% w/v chitin, to induce chitinase) and without fortification of colloidal chitin. It was found that the total cell count, spore count, delta-endotoxin concentration (alkaline solubilised insecticidal crystal proteins), amylase and protease activities were reduced whereas the entomotoxicity and chitinase activity was increased with chitin fortification. The chitinase activity attained a maximum value at 24 h (15 mU/ml) and entomotoxicity of suspended pellet reached highest (26.7 × 109 SBU/L) at 36 h of fermentation with chitin supplementation of SIW. In control (without chitin), the highest value of entomotoxicity of suspended pellet (20.5 × 109 SBU/L) reached at 48 h of fermentation. A quantitative synergistic action of delta-endotoxin concentration, spore concentration and chitinase activity on the entomotoxicity against spruce budworm larvae was observed. 相似文献
89.
Random phosphorylation of the two heads of thymus myosin and the independent stimulation of their actin-activated ATPases 总被引:3,自引:0,他引:3
Like other vertebrate nonmuscle myosins, thymus myosin contains two phosphorylatable light chains. Phosphorylation of these light chains regulates the actin-activated ATPase of this myosin. The time courses for the phosphorylation of both monomeric and filamentous thymus myosin by gizzard myosin light chain kinase fitted single exponentials to greater than 85% phosphorylation. This indicates that the two heads of thymus myosin are phosphorylated at the same rate and suggests that these phosphorylations are random processes. The actin-activated ATPases of thymus myosins with different levels of light chain phosphorylation were also determined. A linear relationship was obtained between the extent of light chain phosphorylation and stimulation of the actin-activated ATPase. Since thymus myosin appears to be phosphorylated randomly, this linear relationship indicates that phosphorylation of one head of thymus myosin stimulates the actin-activated ATPase of that head independently of the phosphorylation of the second head. The apparent random phosphorylation of thymus myosin light chains contrasts with the reported ordered phosphorylation of the light chains of filamentous smooth (gizzard) muscle myosin. Also, while the actin-activated ATPases of the two heads of thymus myosin are regulated independently, both heads of gizzard myosin must be phosphorylated before the ATPase of either head is activated by actin. 相似文献
90.
We have studied the morphology and vein branching of rosette leaves in Arabidopsis thaliana mutants as and sa, which proved to be alleles of the A.thaliana AS1 and AS2 genes, respectively. We have also analyzed the localization of bioactive auxin, as measured by the expression of the DR5::GUS transgene, as well as the expression patterns of BP, as measured by the expression of the BP::GUS transgene in leaves of the mutants. In mature leaves of the mutants, BP was expressed ectopically. Furthermore, the mutants showed some defects in the localization and concentration of free auxin compared to the wild type. Our results of studying new alleles of AS1 and AS2 support their role in control of class I KNOX genes and auxin transport. 相似文献