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1.

Background

Whereas estrogen receptors are present in immune cells, it is not known if they are phosphorylated to regulate immune cell functions. Here we determined the phosphorylation status of estrogen receptor α (ERα) at residue serine 216 in mouse neutrophils and examined its role in migration and infiltration. Serine 216 is the conserved phosphorylation site within the DNA binding domains found in the majority of nuclear receptors.

Methodology/Principal Findings

A phospho-peptide antibody specific to phosphorylated serine 216 and ERα KO mice were utilized in immunohistochemistry, double immuno-staining or Western blot to detect phosphorylation of ERα in peripheral blood as well as infiltrating neutrophils in the mouse uterus. Transwell assays were performed to examine migration of neutrophils. An anti-Ly6G antibody identified neutrophils. About 20% of neutrophils expressed phosphorylated ERα at serine 216 in peripheral white blood cells (WBC) from C3H/HeNCrIBR females. Phosphorylation was additively segregated between C3H/HeNCrIBR and C57BL/6 females. Only neutrophils that expressed phosphorylated ERα migrated in Transwell assays as well as infiltrated the mouse uterus during normal estrous cycles.

Conclusions/Significance

ERα was phosphorylated at serine 216 in about 20% of mouse peripheral blood neutrophils. Only those that express phosphorylated ERα migrate and infiltrate the mouse uterus. This phosphorylation was the first to be characterized in endogenous ERα found in normal tissues and cells. Phosphorylated ERα may have opened a novel research direction for biological roles of phosphorylation in ERα actions and can be developed as a drug target for treatment of immune-related diseases.  相似文献   
2.
Association of a sulfated galactosyl ceramide, sulfatide, with the viral envelope glycoprotein hemagglutinin (HA) delivered to the cell surface is required for influenza A virus (IAV) replication through efficient translocation of the newly synthesized viral nucleoprotein from the nucleus to the cytoplasm. To determine whether the ectodomain of HA can bind to sulfatide, a secreted-type HA (sHA), in which the transmembrane region and cytoplasmic tail were deleted, was generated by using a baculovirus expression system. The receptor binding ability and antigenic structure of sHA were evaluated by a hemagglutination assay, solid-phase binding assay and hemagglutination inhibition assay. sHA showed subtype-specific antigenicity and binding ability to both sulfatide and gangliosides. Kinetics of sHA binding to sulfatide and GD1a was demonstrated by quartz crystal microbalance (QCM) analysis. QCM analysis showed that the sHA bound with the association rate constant (k on) of 1.41?×?104 M?1 sec?1, dissociation rate constant (k off) of 2.03?×?10?4 sec?1 and K d of 1.44?×?10?8 M to sulfatide immobilized on a sensor chip. The k off values of sHA were similar for sulfatide and GD1a, whereas the k on value of sHA binding to sulfatide was 2.56-times lower than that of sHA binding to GD1a. The results indicate that sulfatide directly binds to the ectodomain of HA with high affinity.  相似文献   
3.
Introducing a sulfamide moiety to our coumarin derivatives afforded enhanced Raf/MEK inhibitory activity concomitantly with an acceptable PK profile. Novel sulfamide 17 showed potent HCT116 cell growth inhibition (IC50 = 8 nM) and good PK profile (bioavailability of 51% in mouse), resulting in high in vivo antitumor efficacy in the HCT116 xenograft (ED50 = 4.8 mg/kg). We confirmed the sulfamide moiety showed no negative impact on tests run on the compound to evaluate DMPK (PK profiles in three animal species, CYP inhibition and CYP induction) and the safety profile (hERG and AMES tests). Sulfamide 17 had favorable properties that warranted further preclinical assessment  相似文献   
4.
To elucidate the aberrant growth properties of rheumatoid synoviocytes, we have examined the gene expression profile of rheumatoid synovial fibroblasts (RSFs) and compared with that of normal synovial fibroblasts (NSF). Gene expression profile analysis was conducted with synoviocyte cultures obtained from five rheumatoid arthritis (RA) patients and five control cases using a commercial cDNA array containing the defined 588 cancer-related genes. The results were confirmed by real-time RT-PCR. Gene expression levels for the platelet-derived growth factor receptor alpha (PDGFRalpha), plasminogen activator inhibitor-1 (PAI-1), and stromal cell derived factor 1A (SDF1A) are constitutively augmented in RSF compared with NSF. The mRNA levels of PDGFRalpha, PAI-1, and SDF1A in RSF over NSF were 4.6-, 14-, and 2.8-fold, respectively, by real-time RT-PCR. In fact, we found that RSFs showed greater sensitivity to the cell proliferative effect of PDGF. T his aberrant gene expression profile suggests that RSF may have retained the premature phenotype of primordial synoviocytes.  相似文献   
5.
Lung vascular permeability is acutely increased by high-pressure and high-volume ventilation. To determine the roles of mechanically activated cytosolic PLA2 (cPLA2)and Clara cell secretory protein (CCSP), a modulator of cPLA2 activity, we compared lung injury with and without a PLA2 inhibitor in wild-type mice and CCSP-null mice (CCSP-/-) ventilated with high and low peak inflation pressures (PIP) for 2- or 4-h periods. After ventilation with high PIP, we observed significant increases in the bronchoalveolar lavage albumin concentrations, lung wet-to-dry weight ratios, and lung myeloperoxidase in both genotypes compared with unventilated controls and low-PIP ventilated mice. All injury variables except myeloperoxidase were significantly greater in the CCSP-/- mice relative to wild-type mice. Inhibition of cPLA2 in wild-type and CCSP-/- mice ventilated at high PIP for 4 h significantly reduced bronchoalveolar lavage albumin and total protein and lung wet-to-dry weight ratios compared with vehicle-treated mice of the same genotype. Membrane phospho-cPLA2 and cPLA2 activities were significantly elevated in lung homogenates of high-PIP ventilated mice of both genotypes but were significantly higher in the CCSP-/- mice relative to the wild-type mice. Inhibition of cPLA2 significantly attenuated both the phospho-cPLA2 increase and increased cPLA2 activity due to high-PIP ventilation. We propose that mechanical activation of the cPLA2 pathway contributes to acute high PIP-induced lung injury and that CCSP may reduce this injury through inhibition of the cPLA2 pathway and reduction of proinflammatory products produced by this pathway.  相似文献   
6.

Objective

Presepsin is highlighted as a diagnostic and prognostic marker of sepsis. Little information is available regarding the accurate association between presepsin levels and the degree of kidney function. We analyzed presepsin levels in patients with a glomerular filtration rate (GFR) in the categories G1 to G5, evaluated via inulin renal clearance test, and receiving hemodialysis (HD).

Methods

Patients who were not receiving HD were included if they had undergone inulin renal clearance measurements for the accurate measurement of GFR (measured GFR), and patients who were receiving hemodialysis (HD) were included if they had anuria. Exclusion criteria were infection, cancer, liver disease, autoimmune disorders, or steroid or immunosuppressant use. GFR category was defined as follows; G1: GFR ≥ 90 ml/min/1.73m2, G2: GFR = 60 to 90 ml/min/1.73m2, G3: GFR = 30 to 60 ml/min/1.73m2, G4: GFR = 15 to 30 ml/min/1.73m2, G5: GFR ≤ 15 ml/min/1.73m2.

Results

Seventy-one patients were included. The median (IQR) presepsin values of patients in each GFR category were as follows: G1 + G2: 69.8 (60.8–85.9) pg/ml; G3: 107.0 (68.7–150.0) pg/ml; G4: 171.0 (117.0–200.0) pg/ml; G5: 251.0 (213.0–297.5) pg/ml; and HD: 1160.0 (1070.0–1400.0) pg/ml. The log-transformed presepsin values, excluding patients receiving HD, inversely correlated with the measured GFR (Pearson’s correlation coefficient = -0.687, P < 0.001). The multivariate analysis revealed that measured GFR and hemoglobin levels significantly correlated with elevated presepsin levels.

Conclusion

Presepsin levels were markedly high in patients receiving HD, similar to values seen in patients with severe sepsis or septic shock. In patients who were not receiving HD, presepsin levels increased as GFR decreased. Thus, the evaluation of presepsin levels in patients with chronic kidney disease requires further consideration, and a different cutoff value is needed for diagnosing sepsis in such patients.  相似文献   
7.
BACKGROUND AND AIMS: Betula ermanii, B. maximowicziana and B. platyphylla var. japonica have heterophyllous leaves (i.e. early leaves and late leaves) and are typical pioneer species in northern Japan. Chemical and physical defences against herbivores in early and late leaves of these species were studied. METHODS: Two-year-old seedlings were grown under full sunlight in a single growing season. Three-week-old leaves of each seedling were harvested three times (May, July and October). Total phenolics and condensed tannin content were determined for chemical defence and leaf toughness and trichome density were assessed for physical defence. Defoliation of early leaves in May was also performed to study the contribution of early leaves to subsequent growth. KEY RESULTS: Chemical and physical defences were greater in early than late leaves in B. platyphylla and B. ermanii, whereas the reverse was true in B. maximowicziana. In contrast to its weak chemical defences, the trichome density in B. maximowicziana was very high. In B. platyphylla and B. ermanii, the relative growth rates (RGR) were greater early in the growing season. Negative effects on growth of removal of early leaves were significant only in B. platyphylla. CONCLUSIONS: B. platyphylla and B. ermanii invest in defence in early rather than late leaves, since early leaves are crucial to subsequent growth. In contrast, B. maximowicziana more strongly defends its late leaves, since its RGR is maintained at the same level throughout the growing season.  相似文献   
8.
A gene of Porphyra yezoensis, coding for the translation elongation factor 1 (EF-1), was isolated from a P. yezoensis genomic library. The coding of 1347 nucleotides encodes a polypeptide of 449 amino acids which exhibits sequence similarity as the known EF-1. An intron is located in the 5 untranslated region. Comparison of the deduced amino acid sequence showed higher similarity to the Porphyra purpurea EF-1tef-c (97%) than to the P. purpurea EF-1tef-s (61%). The mRNA was detected both in the leafy gametophyte and filamentous sporophyte by RT-PCR. The nucleotide sequence data reported in this paper will appear in the DDBJ/EMBL/GenBank databases under accession number AB098024.  相似文献   
9.
10.
2-(2,6-Diisopropylphenyl)-5-hydroxy-1H-isoindole-1,3-dione (5HPP-33), which was obtained during our previous structural development studies on thalidomide, was revealed to possess potent tubulin-polymerization-inhibiting activity, comparable to that of the known tubulin-polymerization inhibitors, rhizoxin and colchicine. A major metabolite of thalidomide, 5-hydroxythalidomide, which possesses a hydroxyl group at the position corresponding to that of 5HPP-33, also showed moderate inhibitory activity.  相似文献   
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