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PubMed1992

Pharmacological profile of HS-142-1, a novel nonpeptide atrial natriuretic peptide antagonist of microbial origin. I. Selective inhibition of the actions of natriuretic peptides in anesthetized rats.

HS-142-1, a novel polysaccharide, isolated from the culture broth of Aureobasidium pullulans var. melanigenum, has been found to inhibit selectively the binding of [125I]atrial natriuretic peptide (ANP) to the guanylyl cyclase-linked ANP receptor (ANP-B receptor) and production of cyclic GMP by ANP. The effect of this compound on renal and vascular actions evoked by exogenously administered natriuretic peptides was examined in anesthetized rats. The increase in urine flow and in the urinary excretion of sodium elicited by human ANP or porcine brain natriuretic peptide was prevented by pretreatment with HS-142-1. The prevention was accompanied by the inhibition of increase in urinary cyclic GMP excretion. In addition, these renal responses were rapidly reversed by an injection of HS-142-1 during ANP infusion. Higher doses of HS-142-1 did not alter the increase in urine flow and in the urinary excretion of sodium evoked by furosemide, and HS-142-1 alone showed no significant change in these renal parameters. Hypotensive action elicited by human ANP was also prevented by the pretreatment with HS-142-1 and rapidly reversed by treatment with HS-142-1 during ANP infusion. These results clearly demonstrate that HS-142-1 acts as an antagonist for ANP-B receptor in vivo. HS-142-1, then, provides a new tool for the study of the physiological and pathophysiological roles of ANP.

Anesthesia↗

PubMed1992

Inhibition by HS-142-1, a novel nonpeptide atrial natriuretic peptide antagonist of microbial origin, of atrial natriuretic peptide-induced relaxation of isolated rabbit aorta through the blockade of guanylyl cyclase-linked receptors.

HS-142-1, a specific nonpeptide antagonist for the atrial natriuretic peptide (ANP) receptor, equally blocked rat ANP (rANP)-, porcine brain natriuretic peptide-, or porcine C-type natriuretic peptide-stimulated GMP production in cultured bovine aortic smooth muscle (BASM) and bovine aortic endothelial (BAE) cells in a concentration-dependent fashion, at concentrations of 1-300 micrograms/ml. But, even at 300 micrograms/ml, HS-142-1 only weakly inhibited the specific binding of 125I-rANP to the BASM and BAE cells, where only a small portion of the binding sites are linked to guanylyl cyclase. Further, with BAE cell membranes, HS-142-1 recognized only the 135-kDa ANP receptor, which is thought from 125I-rANP affinity cross-linking studies to be the guanylyl cyclase-linked receptor. HS-142-1 also, if anything, inhibited the labeling of 135-kDa ANP receptors in the affinity cross-linking studies with BASM membranes, suggesting that a major portion of the 135-kDa ANP receptors are HS-142-1 insensitive and only a small portion of the 135-kDa ANP receptors are responsible for the blockade by HS-142-1 of GMP production in BASM cells. At a concentration of 100 micrograms/ml, HS-142-1 reversibly prevented ANP-induced relaxation of the isolated rabbit thoracic aorta induced to contract with 3 x 10(-7) M phenylephrine, but not the relaxation induced by sodium nitroprusside, isoproterenol, or papaverine. These results suggest that HS-142-1 specifically inhibits natriuretic peptide-induced vasorelaxation through the blockade of guanylyl cyclase-linked natriuretic peptide receptors. HS-142-1 thus will be a powerful tool for understanding the physiological roles, in vasculature, of natriuretic peptides, which contribute to the homeostasis of blood pressure and intravascular volume.

Animals↗

PubMedDate not supplied

Differential effects of transforming growth factor-beta1, a fibrogenic factor, on macrophage-like cells (HS-P) and myofibroblastic cells (MT-9) in vitro.

Transforming growth factor-beta1 (TGF-beta1) produced by infiltrating macrophages plays a role in fibrotic disorders through the induction of myofibroblasts. To explore possible mechanisms by which TGF-beta1 may act in this context, we investigated effects of TGF-beta1 on macrophage-like (HS-P) and myofibroblastic (MT-9) cells, two novel cell lines developed by us. Immunocytochemically, the addition of TGF-beta1 (0, 0.1, 0.5, and 1.0 ng/ml) dose-dependently suppressed the expressions of antigens recognized by macrophage/histiocyte-specific antibodies (ED1 and ED2) in HS-P cells, whereas the addition concomitantly increased the number of anti-alpha-smooth muscle actin antibody-positive myofibroblastic cells, suggesting a possible phenotypical modulation of macrophages into myofibroblasts in the fibrotic lesions. By contrast, MT-9 cells did not show such immunophenotypical changes following TGF-beta1 addition. DNA synthesis, measured by tritiated thymidine-incorporation, was inhibited in a dose-dependent manner in MT-9 cells by TGF-beta1 addition (0, 0.1, 0.2, 0.5, 1.0, 5, and 10 ng/ml), but that in HS-P cells was unchanged. Northern blot analysis revealed that expressions of cell cycle-related early genes, c-jun and c-myc, were increased in HS-P cells after TGF-beta1 (1 ng/ml) addition, with c-jun showing peak expression prior to c-myc. By contrast, the peak expressions of c-jun and c-myc were delayed in TGF-beta1 (1 ng/ml)-added MT-9 cells, and their levels were less in MT-9 cells than in HS-P cells. Furthermore, TGF-beta1 (1 and 10 ng/ml) induced DNA laddering in MT-9 cells, but did not in HS-P cells. Based on these findings, it was speculated that TGF-beta1 could have induced G1 arrest in cell cycle and apoptosis in MT-9 cells. The present study showed that there were significant differences in the effects of TGF-beta1 between macrophage-like HS-P cells and myofibroblastic MT-9 cells, presumably depending on divergent susceptibilities to TGF-beta1 between both cell types. Because such cell types are key cells in the fibrogenesis, HS-P and MT-9 might be useful models for investigating the pathogenesis of fibrosis in vitro.

Animals↗

PubMed1997

Analysis of enhancer function of the HS-40 core sequence of the human alpha-globin cluster.

HS-40 is the major regulatory element of the human alpha-globin locus, located 40 kb upstream of the zeta-globin gene. To test for potential interactions between HS-40 and the beta- or the gamma-globin gene promoters in stable transfection assays, the HS-40 core sequence was cloned upstream of either the beta promoter or the gamma promoter driving the neomycin phosphotransferase gene and enhancer activity was measured using a colony assay. In K562 or in MEL cells, enhancer activity of HS-40 was higher than that of the individual core sequences of the DNase I hypersensitive sites (HS) of the beta-globin locus control region (LCR), and approximately 60% of the enhancer activity of a 2.5 kb microLCR, which contains the core elements of DNase I hypersensitive sites 1-4. In contrast to the synergistic interaction between the DNase I hypersensitive sites of beta locus LCR, combination of HS-40 with these DNase I hypersensitive sites failed to display cooperativity in K562 cells and inhibited enhancer function in MEL cells. Inhibition of enhancer function was also observed when two copies of the HS-40 were arranged tandemly. We conclude that the core element of HS-40 (i) is a powerful enhancer of gamma- and beta-globin gene expression, (ii) in contrast to other classical enhancers, acts best as a single copy, (iii) does not cooperate with the regulatory elements of the beta-globin locus control region.

Animals↗

PubMed2004

Alterations in gene expression induced in day-9 mouse embryos exposed to hyperthermia (HS) or 4-hydroperoxycyclophosphamide (4CP): analysis using cDNA microarrays.

Teratogen-induced alterations in gene expression play an important role in the genesis of malformations in animals. The recent development of DNA microarrays now offers the opportunity to monitor global changes in gene expression and therefore the potential to obtain significant new information concerning both normal and abnormal development. RNA was isolated from day-9 mouse embryos at 1 and 5 h after exposure to hyperthermia (HS) or 4-hydroperoxycyclophosphamide (4CP) and compared to RNA isolated from concurrent controls using mouse cDNA microarrays. Cy5/Cy3 intensity data were extracted using Spot-on Image software and then normalized using the statistical software program R/maanova. Differentially expressed genes were identified using a linear mixed-effects model and p values derived from t-test statistics. Approximately 9000 genes show statistically significant alterations in expression in day-9 mouse embryos exposed to HS or 4CP. HS and 4CP also induce alterations in the expression of distinct sets of genes, e.g., DNA replication/repair, cell cycle, signal transduction, and transcription-related genes. As expected, a variety of heat shock genes are upregulated by HS but not 4CP. Among genes whose expression is altered by both HS and 4CP, cluster analysis identified three p53 target genes (Cyclin G1, Gtse1, and Mdm2), and follow up studies confirmed that p53 is activated in embryos exposed to these two teratogens. In addition, cluster analyses also revealed that HS but not 4CP induces the downregulation of genes encoding key enzymes in the cholesterol biosynthesis pathway. Thus, our microarray data have identified one potentially important pathway (p53) common to both HS- and 4CP-induced teratogenesis and another pathway (cholesterol biosynthesis) potentially important, but specific to HS-induced teratogenesis.

Animals↗

PubMed1979

Kinetics of red cell membrane phosphorylation: altered affinity of HS membrane protein acceptors.

Membrane ghosts were prepared from red blood cells of normal and hereditary spherocytosis (HS) subjects. Time dependent phosphorylation studies of the membrane (in the presence of gamma labelled AT32P) showed that the HS membrane appeared to incorporate less phosphate than the normal membrane but the results were not significantly different. Using the initial linear rate of phosphorylation and varying the ATP concentration, it was found that the Michaelis constant (Km) for the normal membrane was 24.8 microns ATP and Vmax was 0.120 nmol phosphate bound/mg membrane protein/min. These values for the HS membrane were found to be 39.0 and 0.118 respectively. In one family the affected mother and son each showed a positive cooperativity effect for similar reciprocal plots. This indicates that phosphorylation of various HS membrane proteins may be an ordered rather than random process and suggests biochemical heterogencity of the HS condition. The constants, Km and Vmax, however, were found to be similar to the rest of HS subjects studied. Crude extracts of the enzyme protein kinase, which catalyses the membrane phosphorylation, showed no significant difference in the Km and Vmax value in HS compared with that from normal red cells. The kinetic difference in phosphorylation is probably due to abnormalities in the membrane protein(s) which accept the phosphate from protein kinase in HS red cells.

Adenosine Triphosphate↗

PubMed1991

Solutol HS 15, nontoxic polyoxyethylene esters of 12-hydroxystearic acid, reverses multidrug resistance.

A recently developed non-ionic surfactant called Solutol HS 15 (poly-oxyethylene esters of 12-hydroxystearic acid), with low toxicity in vivo, was shown to reverse completely the multidrug resistance of KB 8-5 and KB 8-5-11 human epidermoid carcinoma cells in vitro but did not potentiate drug toxicity in drug-sensitive KB 3-1 cells. At a concentration of 10% of its own IC50 (mean concentration of drug that causes 50% inhibition of cell growth compared to controls), Solutol HS 15 produced a 35-, 28-, and 42-fold reduction in the resistance of KB 8-5-11 cells to colchicine, vinblastine, and doxorubicin, respectively. Solutol HS 15 was relatively much more potent than the prototypic reversing agent, verapamil, for reversing colchicine resistance, compared to the ability of each agent to reverse colchicine resistance, compared to the ability of each agent to reverse vinblastine resistance. Like verapamil, Solutol HS 15 promoted a 50-fold accumulation of rhodamine 123 in KB 8-5-11 cells, as measured by flow cytometry. Also, Solutol HS 15 and verapamil reduced the efflux of rhodamine 123 from KB 8-5-11 cells previously loaded with rhodamine 123 to a similar low rate. Solutol HS 15 did not affect the transport of alanine or glucose into KB 8-5-11 cells, indicating that its effect upon membrane active transport is not entirely nonspecific. Considering their different structure and different relative potency for reversing colchicine resistance, Solutol HS 15 and verapamil probably reverse multidrug resistance by different mechanisms. Solutol HS 15 merits consideration as a potential therapeutic agent because of its effectiveness for reversing multidrug resistance in vitro and its low toxicity in vivo.

Carcinoma, Squamous Cell↗

PubMed1996

Limited proteolysis of human alpha2-HS glycoprotein/fetuin. Evidence that a chymotryptic activity can release the connecting peptide.

alpha2-HS glycoprotein is a major protein of human plasma whose function is still obscure. A proteolytically processed form of alpha2-HS glycoprotein lacking a segment of 40 amino acid residues bridging its heavy and light chain portions ("connecting peptide") has been described suggesting that this peptide is released by post-translational processing to fulfill biological role(s) of alpha2-HS glycoprotein. To test this hypothesis we investigated how the connecting peptide is released from the parental molecule by limited proteolysis. We developed monoclonal antibodies to various portions of the connecting peptide and its NH2-terminal flanking region which cross-react with the native alpha2-HS glycoprotein. Purified alpha2-HS glycoprotein from human plasma was subjected to limited proteolysis by proteinases including trypsin, chymotrypsin, elastase plasmin, kallikrein, thrombin, and renin. Immunoprint analysis of the proteolytic digests indicated that alpha2-HS glycoprotein is readily cleaved in its connecting peptide region. NH2-terminal amino sequence analysis of the generated fragments demonstrated that a single proteinase, chymotrypsin, cleaves the critical Leu-Leu bond flanking the NH2-terminal portion of the connecting peptide region. Most but not all of the other proteinase cleavage sites map to a short stretch of 9 residues located in the center portion of the connecting peptide region. Immunoprint analysis of plasma samples from patients with sepsis demonstrate that the connecting peptide region is cleaved under pathological conditions. Our results indicate that the connecting peptide and/or fragments thereof are readily releasable from alpha2-HS glycoprotein in vitro and in vivo.

Amino Acid Sequence↗

PubMed1998

Levels of antibodies to transferrin and alpha 2-HS glycoprotein in women with and without endometriosis.

PROBLEM: To establish an enzyme-linked immunosorbent assay (ELISA) for determining the levels of antibodies to transferrin and alpha 2-HS glycoprotein in the serum of women with and without endometriosis. METHOD OF STUDY: Serum samples were obtained from 105 normal women, who were randomly selected for a population-based epidemiologic study, and 123 patients with active endometriosis. An ELISA using transferrin and alpha 2-HS glycoprotein as antigens was established. RESULTS: The levels of antibodies to transferrin and alpha 2-HS glycoprotein in the serum of patients with endometriosis were approximately 21 times higher than those in the serum of control subjects without endometriosis. Only 2% of control subjects had false positive levels of these antibodies, and 5% of patients with endometriosis had false negative levels of these antibodies (specificity, 98.1 and 98.1, respectively, for anti-transferrin and anti-alpha 2-HS glycoprotein; sensitivity, 95 and 96.7, respectively, for anti-transferrin and anti-alpha 2-HS glycoprotein). CONCLUSIONS: Patients with endometriosis have significantly higher levels of antibodies to transferrin and alpha 2-HS glycoprotein than control subjects. Testing women for antibodies to transferrin and alpha 2-HS glycoprotein will provide a specific noninvasive diagnosis of endometriosis.

Adolescent↗

PubMed2003

Impact of Solutol HS 15 on the pharmacokinetic behaviour of colchicine upon intravenous administration to male Wistar rats.

In the current investigation, the alkaloid colchicine was administered intravenously to male Wistar rats both as a solution in isotonic sodium chloride (NaCl 0.9%, control group) and in NaCl 0.9%:Solutol HS 15 (95:5) at 1.5 mg/kg. At predetermined time points, plasma and urine were collected from the animals and analysed for colchicine and its demethylated metabolites by LC/MS-MS. In the presence of Solutol HS 15, colchicine clearance (CI) was significantly decreased and its maximum plasma concentration (c(max)) was significantly increased as compared to the control group (CI: 15.6+/-7.0 ml/min/kg vs 34.3+/-2.3 ml/min/kg; c(max) 3055.1+/-587.4 h vs 1260.1+/-223.7 h; p<0.05). Moreover, the amount of parent colchicine excreted into urine was markedly increased in the Solutol HS 15 treated group (41.50+/-3.23 vs 1.17+/-0.41% of total dose; p<0.05). By contrast, there was no statistically significant difference but a trend to lower values only in the volume of distribution (V(d) 13.3+/-2.2 l/h vs 31.4+/-17.7 l/h, p=0.35). The half-lives for the first (t(1/2 1stphase). 0.21+/-0.02 h vs 0.20+/-0.03 h) and second phase (t(1/2 2ndphase). 18.5+/-6.9 h vs 18.3+/-7.7 h) did not differ significantly in dependence on the dosing vehicle. The free fraction in rat plasma (FF), the blood/plasma (lambda) and erythrocyte/plasma concentration ratios (K(e)) were not significantly changed in the presence of different concentrations of Solutol HS 15 compared with surfactant-free incubations (overall means: 72.25+/-0.50% for FF, 0.80+/-0.02 for lambda, 0.46+/-0.04 for K(e)). In vitro, in rat hepatocytes, the clearance of colchicine was significantly reduced at 0.003% Solutol HS 15 present in the incubation medium (0.86+/-0.15 microl/min/10(-6) cells vs 1.46+/-0.06 microl/min/10(-6) cells). As colchicine exhibits a comparatively high aqueous solubility, an impact of Solutol HS 15 on the solubility of the alkaloid is very unlikely to be a reason for the observed effect. Therefore, our results indicate that the most likely reasons for the changed pharmacokinetic behaviour of colchicine in the presence of Solutol HS 15 are alterations of metabolism and/or transport as well as distribution and elimination processes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1996

HS-:O2 oxidoreductase activity of Cu,Zn superoxide dismutase.

Cu,Zn-Superoxide dismutase (SOD, EC 1.15.1.1) catalyzes HS- oxidation according to the reaction: HS- + H+ + 02 --> S(0) + H202. At pH 7.8, 20 degrees C, 280 microM 02, and 100 microM HS-, the rate of HS- oxidation is 0.2 mol min-1 (mol SOD)-1. The affinities of the enzyme for HS- and O2 are consistent with previous measurements for these substrates in connection with other enzymic reactions. The rate of HS oxidation by SOD is slower than that provided by other cellular mechanisms, and it is unlikely to be of physiological significance. However, using </= 1 microM SOD the rate of HS- oxidation gradually accelerates so that after 1 h it can be 600 times faster than the initial rate. This is caused by a nonenzymic oxidative chain reaction that is not self-sustaining, but requires "seeding" from the enzymic reaction.

Animals↗

PubMed2006

Improvement of HS-SPME for analysis of volatile organic compounds (VOC) in water samples by simultaneous direct fiber cooling and freezing of analyte solution.

The sensitivity and precision of headspace solid-phase micro extraction (HS-SPME) at an analyte solution temperature (T (as)) of +35 degrees C and a fiber temperature (T (fiber)) of +5 degrees C were compared with those for HS-SPME at T (as) and T (fiber) of -20 degrees C for analysis of the volatile organic compounds benzene, 1,1,1-trichloroethane, trichloroethylene, toluene, o-xylene, ethylbenzene, m/p-xylene, and tetrachloroethylene in water samples. The effect of simultaneous fiber cooling and analyte solution freezing during extraction was studied. The compounds are of different hydrophobicity, with octanol/water partition coefficients (Kow) ranging from 126 and 2511. During a first set of experiments the polydimethylsiloxane (PDMS) SPME fiber was cooled to +5 degrees C with simultaneous heating of the aqueous analyte solution to +35 degrees C. During a second set of experiments, both SPME fiber holder and samples were placed in a deep freezer maintained at -20 degrees C for a total extraction time of 30 min. After approximately 2 min the analyte solution in the vial began to freeze from the side inwards and from the bottom upwards. After approximately 30 min the solution was completely frozen. Analysis of VOC was performed by coupling HS-SPME to gas chromatography-mass spectrometry (GC-MS). In general, i.e. except for tetrachloroethylene, the sensitivity of HS-SPME increased with increasing compound hydrophobicity at both analyte solution and fiber temperatures. At T (as) of +35 degrees C and T (fiber) of +5 degrees C detection limits of HS-SPME were 0.5 microg L(-1) for benzene, 1,1,1-trichloroethane, trichloroethylene, and tetrachloroethylene, 0.125 microg L(-1) for toluene, and 0.025 microg L(-1) for ethylbenzene, m/p-xylene, and o-xylene. In the experiments with T (as) and T (fiber) of -20 degrees C, detection limits were reduced for compounds of low hydrophobicity (Kow<501), for example benzene, toluene, 1,1,1-trichloroethane, and trichloroethylene. In the concentration range 0.5-62.5 microg L(-1), the sensitivity of HS-SPME was enhanced by a factor of approximately two for all compounds by performing the extraction at -20 degrees C. A possible explanation is that freezing of the water sample results in higher concentration of the target compounds in the residual liquid phase and gas phase (freezing-out), combined with enhanced adsorption of the compounds by the cooled fiber. The precision of HS-SPME, expressed as the relative standard deviation and the linearity of the regression lines, is increased for more hydrophobic compounds (Kow>501) by simultaneous direct fiber cooling and freezing of analyte solution. Background contamination during analysis is reduced significantly by avoiding the use of organic solvents.

Journal Article↗

PubMed2006

High-sensitivity C-reactive protein (hs-CRP) level in children with nephrotic syndrome.

The aim of this study was to assess the serum concentration of high-sensitivity C-reactive protein (hs-CRP) in children with nephrotic syndrome (NS) treated with prednisone and cyclosporine A (CyA). Patients were divided into three groups: (I) 20 NS children (aged 4-14 years) in relapse and examined twice, (A) before treatment and (B) after proteinuria regression (a 3-4 week course of prednisone therapy); (II) 20 children with steroid-dependent or steroid-resistant NS, treated with CyA, also examined twice, (D) before treatment with CyA, (E) 6 months after therapy. A control group (C) consisted of 20 healthy children. Serum hs-CRP level was determined by a nephelometric method with a Behring Nephelometer 100 Analyzer, Dade Behring. The results showed that median hs-CRP concentration was the highest in children with relapsing steroid-sensitive NS before treatment (IA). After proteinuria regression (IB), the hs-CRP level had decreased and did not differ from that of healthy controls (C) (P>0.05). In group II, before CyA administration (IID), the level of hs-CRP was normal, but it had increased after 6 months of treatment (IIE) up to a level six-times higher than that of the control group (P<0.01). We concluded that, in children with steroid-sensitive nephrotic syndrome in relapse, the serum hs-CRP level is increased but returns to normal after 3-4 weeks of glucocorticoid treatment. In children chronically treated with CyA due to NS, serum hs-CRP level increases significantly during the therapy.

Adolescent↗

PubMed2006

Evidence for the transglycosylation of complex type oligosaccharides of glycoproteins by endo-beta-N-acetylglucosaminidase HS.

Transglycosylation activity of endo-beta-N-acetylglucosaminidase HS (Endo HS) was investigated using native human transferrin as a donor of an asparagine-linked oligosaccharide and p-nitrophenyl-beta-d-glucose (PNP-beta-d-Glc) as an acceptor of the oligosaccharide. The amount of the product increased dependent on the concentration of the acceptors. Absorption spectrum, exoglycosidase digestion and matrix assisted laser desorption and ionization-time of flight (MALDI-TOF) mass analysis of the transglycosylation product indicated that the asialobiantennary complex type oligosaccharide of human transferrin was transferred to PNP-beta-d-Glc. Endo HS also transferred the oligosaccharide of human transferrin to PNP-alpha-d-Glc, PNP-alpha-d-Gal, PNP-beta-d-Gal, PNP-beta-d-Man, PNP-beta-d-Xyl, PNP-beta-d-GlcNAc, and PNP-glycerol at a different rate. No apparent difference in the K(m) value for human transferrin as an oligosaccharide donor was observed using different acceptors, PNP-beta-d-Glc and PNP-glycerol. The amount of the transglycosylation product successively increased and became constant and then very slightly decreased during the course of enzyme reaction. Endo HS was also transferred the triantennary complex type oligosaccharide of calf fetuin and the bi-, tri-, and tetrantennary complex type oligosaccharides of human alpha(1)-acid glycoprotein to PNP-beta-d-Glc. Furthermore, Endo HS transferred an asparagine-linked oligosaccharide from a hen egg glycopeptide to PNP-beta-d-Glc. The results demonstrate that Endo HS can transfer a wide variety of asparagine-linked complex type oligosaccharides to various monosaccharides. Endo HS was distinct from other enzymes in the specificity for oligosaccharide donors and acceptors.

Glycation End Products, Advanced↗

PubMed2006

HS-48 alone has no enhancement role on the expression of human alpha-globin gene cluster.

To investigate the in vivo function of the newly defined DNase I hypersensitive site HS-48 on the whole human alpha-globin gene cluster, the region containing all the other known 5 hypersensitive sites HS-4 to HS-40 was deleted from a 117 kb bacterial artificial chromosome clone bearing the whole human alpha-globin gene cluster. Transgenic mice were generated from this construct. The RNase protection assays showed that with HS-48 left and all the other 5 hypersensitive sites deleted, the expression of human alpha-like globin genes was completely silenced in embryonic, fetal and adult stages in all tissues. This finding indicates that HS-48 alone has no enhancer activity on the expression of human alpha-like globin genes, and that the region of HS-4 to HS-40 already contains all the upstream cis-elements needed for regulating human alpha-like globin genes.

Animals↗

PubMed2004

In vitro investigation on the impact of Solutol HS 15 on the uptake of colchicine into rat hepatocytes.

In the current investigation, the impact of the surface-active formulation ingredient Solutol HS 15 on the uptake of colchicine into freshly isolated rat hepatocytes was investigated using a centrifugal filtration technique through a silicone oil layer. Colchicine is taken up into the cells by an active transport mechanism. When conducting the experiment at 37 degrees C, it was found that at concentrations below its critical micellar concentration (CMC) of 0.021% (0.0003 and 0.003%, w/v), Solutol HS 15 did not impact the uptake of colchicine. By contrast, at a Solutol HS 15 concentration above its CMC (0.03%, w/v), the amount of colchicine taken up into the cells as well as its uptake velocity were significantly decreased. However, in control experiments performed at 4 degrees C, a temperature at which active transport processes should be significantly slowed down, Solutol HS 15 at 0.03% did not affect colchicine uptake and/or its association with the cells. The described findings might be rationalized by inhibition of colchicine transport either due to direct interaction at the transport site or due to alterations of membrane properties in the presence of Solutol HS 15 at concentrations above its CMC. Moreover, a strong molecular interaction between Solutol HS 15 and colchicine as well as an incorporation of colchicine into micelles formed by Solutol HS 15, this way resulting in a limited contact of colchicine with the cells, cannot be excluded as contributors to the observed effect.

Animals↗

PubMed2005

Predictive role of hs-C-reactive protein in patients with antiphospholipid syndrome.

High-sensitive C-reactive protein (hs-CRP) is a marker of inflammation which has been shown in several prospective studies to independently predict myocardial infarction, stroke and peripheral artery disease. Patients with antiphospholipid antibodies (aPL) are at increased risk of recurrent thromboembolic events, but the possibility of predicting this risk seems rather limited. Similarities were recently found between aPL and CRP in the pathology of thrombosis. The current study investigated the predictive role of hs-CRP in a cohort of patients with neurological manifestations. A follow-up investigation was done in a cohort of 55 aPL-positive patients with acute manifestations of neurological disease. hs-CRP levels were measured in all patients at enrollment and were compared to the patients' condition after a median period of 32 months. Lupus anticoagulants were detected according to the Standardization of Lupus Anticoagulants (SSC) of the ISTH. Anticardiolipin tests were performed by a beta2-glycoprotein I-dependent enzyme-linked immunsorbent assay (Pharmacia ELISA). hs-CRP was measured by latex-enhanced turbidometry (dimension RXL, Dade Behring). Cerebral infarctions and transient ischemic attacks were the most frequent cerebral events. In patients with aPL, elevated levels of hs-CRP were closely associated with an increased rate of recurrent or residual symptoms (OR, 12.5; 95% CI, 3.72-41.94) and were not related to other risk factors, except smoking (p<0.05). The rate at which a given patient's condition deteriorated was also related to the level of hs-CRP. In patients with antiphospholipid syndrome (APS), elevated levels of hs-CRP may identify a group of patients which is at high risk of recurrent or residual neurological symptoms and which may benefit from more careful follow-up and from antithrombotic therapy.

Adolescent↗

PubMed2002

Differential hs-CRP reduction in patients with familial hypercholesterolemia treated with aggressive or conventional statin therapy.

BACKGROUND: High sensitivity C-reactive protein (hs-CRP) has emerged as the best studied and most promising marker of inflammation in atherosclerotic vascular disease. MATERIALS AND METHODS: The ASAP (effects of Atorvastatin vs. Simvastatin on Atherosclerosis Progression) study was a 2-year randomised, double-blind trial with 325 familial hypercholesterolemia patients, treated with torvastatin 80 mg or imvastatin 40 mg. Intima media thickness (IMT) of carotid artery segments and hs-CRP levels were determined at baseline, 1 and 2 years. RESULTS: Baseline median hs-CRP values were 2.1 mg/l (interquartile range (IQR) 0.9-5.2) and 2.0 mg/l (IQR 0.8-3.0) and after 2 years these levels decreased to 1.1 mg/l (IQR 0.6-2.4) and 1.5 mg/l (IQR 0.6-3.0) in the atorvastatin 80 mg and simvastatin 40 mg group, respectively. These changes were significant within as well as between the two groups. No correlations were observed between change in hs-CRP after 2 years and change in lipids. A significant correlation was found in univariate analysis between the decrease of hs-CRP and the reduction of IMT. CONCLUSIONS: Our results show that atorvastatin 80 mg reduces hs-CRP levels to a greater extent than simvastatin 40 mg. Furthermore, we show that the extent of hs-CRP reduction is associated with the progression rate of the atherosclerotic process as measured by IMT.

Adult↗