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1.
The applicability of 2-bromoethyl glycosides in carbohydrate synthesis is demonstrated by the synthesis of glycosides of alpha-L-Fuc-(1----2)-D-Gal and beta-D-Gal-(1----4)-D-GlcNAc. The bromoethyl aglycon was transformed into the methoxycarbonylethylthioethyl spacer, which allowed coupling of the sugars to proteins (BSA and KLH).  相似文献   
2.
Purinergic Signalling - Urosepsis is a severe condition often caused by Escherichia coli that spontaneously have ascended the urinary tract to the kidneys causing pyelonephritis and potentially...  相似文献   
3.
Leukotriene B4 (LTB4), a potent chemotactic and immune-modulating lipid mediator, signals via two receptors, BLT1 and BLT2, leading to pro-inflammatory responses in phagocytes. Recently, we reported that BLT1 is the predominating BLT on human umbilical vein endothelial cells (HUVEC) and transmits a variety of functional responses. Here, we demonstrate that, in HUVEC, two BLT1 antagonists (U75302, CP105696) and one BLT2 antagonist (LY255283) possess intrinsic but varying agonist activity for adhesion of neutrophils, up-regulation of E-selectin, ICAM-1 and VCAM-1, and release of MCP-1. These effects were observed after exposure of HUVEC for the drugs for 0.25-6h, persisted for several hours, and were less potent in magnitude as those elicited by LPS. Our findings may have consequences for interpretation of in vitro BLT blockade experiments.  相似文献   
4.
Enzymic hydrolysis of pullulan, followed by acetylation and chromatography, gave acetylated alpha-D-Glcp-(1----6)-alpha-D-Glcp-(1----4)-alpha-D-Glcp-(1----4)-D-Glcp which, with 2-bromoethanol and boron trifluoride etherate in dichloromethane, gave the 2-bromoethyl glycoside. The reactions of the glycoside with methyl 3- mercaptopropionate , methyl 11- mercaptoundecanoate , and octadecanethiol are described, and also its hydrogenolysis to give an ethyl glycoside. The mercaptopropionate -derived, spacer-arm glycoside has been coupled to bovine serum albumin and keyhole limpet haemocyanin.  相似文献   
5.

Background  

Myocardial injury may contribute to unexpected deaths due to pyometra. To detect myocardial damage, measurement of cardiac troponin I (cTnI) is currently the most sensitive and specific method. The aims of the present study were to evaluate presence of myocardial damage in canine pyometra by analysis of cTnI, to explore whether myocardial injury was associated with systemic inflammatory response syndrome (SIRS) and to evaluate whether other clinical or laboratory parameters were associated with cTnI increase.  相似文献   
6.
Chlamydiae are obligate intracellular bacteria, developing inside host cells within chlamydial inclusions. From these inclusions, the chlamydiae secrete proteins into the host cell cytoplasm. A pathway through which secreted proteins can be delivered is the type III secretion system (T3SS). The T3SS is common to several gram-negative bacteria and the secreted proteins serve a variety of functions often related to the modulation of host signalling. To identify new potentially secreted proteins, the cytoplasm was extracted from Chlamydia trachomatis L2-infected HeLa cells, and two-dimensional polyacrylamide gel electrophoresis profiles of [35S]-labelled chlamydial proteins from this extract were compared with profiles of chlamydial proteins from the lysate of infected cells. In this way, CT621 was identified. CT621 is a member of a family of proteins containing a domain of unknown function DUF582 that is only found within the genus Chlamydia . Immunofluorescence microscopy and immunoblotting demonstrated that CT621 is secreted late in the chlamydial developmental cycle and that it is the first chlamydial protein found to be localized within both the host cell cytoplasm and the nucleus. To determine whether CT621 is secreted through the T3SS, an inhibitor of this apparatus was added to the infection medium, resulting in retention of the protein inside the chlamydiae. Hence, the so far uncharacterized CT621 is a new type III secretion effector protein.  相似文献   
7.
The purpose of this study was to investigate the association between tumor tissue levels of total tissue inhibitor of metalloproteinases-1 (TIMP-1) and prognosis in patients with primary breast cancer and to analyze whether measurement of TIMP-1 in tumor extracts added prognostic information to that obtained from measurements of urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 (PAI-1). An established sandwich enzyme-linked immunosorbent assay was thoroughly validated for the measurement of total TIMP-1 in tumor tissue extracts and used to determine levels of total TIMP-1 in 341 detergent-extracted tumor tissue samples from patients with primary breast cancer. The median age of the patients was 56 years (range, 29-75 years), and 164 were lymph node-negative, and 177 were lymph node-positive. The median follow-up time of the patients was 8.5 years (range, 7.3-11.3 years), and during follow-up 153 patients experienced recurrence of disease, and 136 patients died. In univariate survival analysis, we found a significant association between tumor tissue TIMP-1 level and both shorter recurrence-free survival (p = 0.0004) and shorter overall survival (p = 0.03). In multivariate survival analysis, higher tumor tissue TIMP-1 levels significantly and independently predicted shorter recurrence-free survival (p < 0.05, hazard ratios >1, comparing quartiles II-IV with I). In addition, we found that measurement of TIMP-1 levels added prognostic information to that obtained from measurement of PAI-1. In conclusion, high levels of TIMP-1 in tumor tissue extracts are significantly associated with a poor prognosis in patients with primary breast cancer. Furthermore TIMP-1 adds prognostic information to that obtained from PAI-1. However, further validation in independent data sets is needed.  相似文献   
8.
9.
Reaction norms were determined in two natural populations of the perennial plantIris pumila from contrasting light conditions at two levels of photosynthetically active radiation (105 and 35 µmol m–2s–1). Seedlings developed from free-pollinated seed families sampled individually from 19 and 12 randomly selected clonal genotypes in an exposed and a shaded population respectively, were grown in a growth room using a mixed model nested factorial experimental design and scored for a number of phenological and morphological traits. Ambient light conditions significantly affected all of the juvenile traits measured. In both populations, relatively convergent norms of reactions were revealed for leaf appearance dates, as well as for leaf number, suggesting the importance of these traits for functional adjustment to prevailing light conditions. Reaction norms for morphological traits, however, were largely nonparallel, but although often crossing each other, a significant family-by-treatment interaction in the ANCOVAs performed was not detected for any of the traits measured, indicating a small amount of genetic variation for plasticity in these populations. The extent of plastic response to light availability was determined and expressed as an index that estimates the percentage change in a trait value from a high to a low light level. Evolutionary and ecological implications of the observed plastic variations are also discussed.  相似文献   
10.
Valproic acid (VPA) is an anticonvulsant used to treat bipolar disorder, a psychiatric disease associated with disturbances in circadian rhythmicity. Little is known about how VPA affects circadian rhythms. The authors cultured tissues containing the master brain pacemaker for circadian rhythmicity, the suprachiasmatic nuclei (SCN), and skin fibroblasts from transgenic PERIOD2::LUCIFERASE (PER2::LUC) mice and studied the effect of VPA on the circadian PER2::LUC rhythm by measuring bioluminescence. VPA (1 mM) significantly phase advanced the PER2::LUC rhythm when applied at a time point corresponding to the lowest (trough, ~ZT 0) PER2::LUC expression but phase delayed the PER2::LUC rhythm when the drug was administered at the time of highest (peak, ~ZT 12) protein expression. In addition, it significantly increased the overall amplitude of PER2::LUC oscillations at time points at or close to ZT 12 but had no effect on period. Real-time PCR analyses on mouse and human fibroblasts revealed that expressions of other clock genes were increased after 2 h treatment with VPA. Because VPA is known to inhibit histone deacetylation, the authors treated cultures with an established histone deacetylation inhibitor, trichostatin A (TSA; 20 ng/mL), to compare the effect of VPA and TSA on molecular rhythmicity. They found that TSA had similar effects on the PER2::LUC rhythm as VPA. Furthermore, VPA and TSA significantly increased acetylation on histone H3 but in comparison little on histone H4. Lithium is another commonly used treatment for bipolar disorder. Therefore, the authors also studied the impact of lithium chloride (LiCl; 10 mM) on the PER2::LUC rhythm. LiCl delayed the phase, but in contrast to VPA and TSA, LiCl lengthened the PER2::LUC period and had no effect on histone acetylation. These results demonstrate that VPA can delay or advance the phase, as well as increase the amplitude, of the PERIOD2::LUCIFERASE rhythm depending on the circadian time of application. Furthermore, the authors show that LiCl delays the phase and lengthens the period of the PER2::LUC rhythm, confirming previous reports on circadian lithium effects. These different molecular effects may underlie differential chronotherapeutic effects of VPA and lithium.  相似文献   
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