SEARCH · PubMed Health

Results for “Solubility”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

PubMed1998

Soluble interleukin-2 receptor and soluble CD8 antigen levels in serum from patients with solid tumors.

High levels of soluble lymphocyte antigens have been described in a large number of tumors and, particularly, in hematopoietic neoplasms. As previously reported, many antitumor immune responses are IL-2 dependent: clinical observations indicate that a worse survival in advanced tumor patients is related with a decrease of soluble IL-2 levels. A soluble form of CD8 has been described: as found in Hodgkin's disease and acute lymphoblastic leukemia, sCD8 levels have a prognostic value. To explain the significance of these soluble molecules in solid tumors, we a) determinated sIL-2R and sCD8 in 84 patients; b) correlated the expression of p55 chain of IL-2R and CD8 antigen on the cell-surface of peripheral lymphocytes to sIL-2R and sCD8 levels; c) analyzed endogenous IL-2R levels in patients with lung cancer. An increase of sIL-2R was found in 82% of cases, while high levels of sCD8 were observed in 32%; no correlation was observed between sIL-2R and the expression of p55 on the surface of peripheral lymphocytes: IL-2 levels in patients with NSCLC were significatively reduced, when compared to healthy controls, with an inverse relationship between endogenous IL-2 concentration and sIL-2R levels. Whatever may be the physiopathological mechanism of the increase of sIL-2 observed in solid tumors, this rise may contribute to the immunodepression correlated to neoplastic disease. Therefore, higher levels of sIL-2R/IL-2 ratio has a negative biologic prognostic significance. We think that determinating CD8 antigen in the serum can offer a more sensitive and specific measurement of activation of suppressor/cytotoxic T-lymphocytes.

Adult↗

PubMed2004

Changes of soluble fas and soluble fas ligand in serum and peritoneal fluid of infertile patients with endometriosis.

OBJECTIVE: To evaluate the relationship between levels of soluble Fas (sFas) and soluble Fas ligand (sFasL) in serum and peritoneal fluid of endometriosis-associated infertility. METHODS: The soluble Fas ligand and soluble Fas levels in serum and peritoneal fluid of 20 infertile patients with endometriosis were assessed with enzyme-linked immunosorbent assay, and were compared with 14 infertile patients due to chronic pelvic infectious disease and 16 fertile controls. RESULTS: The sFasL levels were significantly higher in infertile patients with endometriosis (175.09 +/- 80.55 pg/mL in serum and 284.50 +/- 152.38 pg/mL in peritoneal fluid) than those of infertile controls (88.47 +/- 43.55 pg/mL in serum and 17.30 +/- 9.62 pg/mL in peritoneal fluid) and fertile controls (16.13 +/- 11.75 pg/mL in serum and 8.84 +/- 2.31 pg/mL in peritoneal fluid). In contrast, as for the sFas levels, infertile patients with endometriosis (828.60 +/- 429.65 pg/mL in serum and 349.61 +/- 288.89 pg/mL in peritoneal fluid) did not show any significant difference compared with those in infertile patients resulting from pelvic infectious disease (868.75 +/- 570.48 pg/mL in serum and 181.76 +/- 157.78 pg/mL in peritoneal fluid) and fertile control (822.26 +/- 129.12 pg/mL in serum and 318.42 +/- 145.16 pg/mL in peritoneal fluid). CONCLUSIONS: Based upon these results, high level of sFasL in serum and peritoneal fluid and thus apoptosis mediated by it may be implicated in the mechanism involved in endometriosis-related infertility.

Ascitic Fluid↗

PubMed1989

Resistance of cytolytic lymphocytes to perforin-mediated killing. Murine cytotoxic T lymphocytes and human natural killer cells do not contain functional soluble homologous restriction factor or other specific soluble protective factors.

CTL and NK cells produce a cytolytic pore-forming protein (perforin, cytolysin) localized in their cytoplasmic granules. These cytotoxic cells are resistant to killing mediated by other lymphocytes and by purified perforin. A membrane factor, known as homologous restriction factor (HRF), has been suggested to confer protection to different cell types against both C- and perforin-mediated lysis. The granules of human large granular lymphocytes have been reported to contain, in addition to perforin, a soluble HRF activity that can be eluted from anion-exchange columns at 115 mM NaCl. Here, we report that a soluble HRF activity is absent in the granules or the cytosol of murine CTL and human NK cells. Our data indicate that the inhibition attributed to HRF could be explained by exogenous EDTA added during granule fractionation. EDTA was shown to bind to Mono Q and to elute at 90 to 120 mM NaCl. A second perforin-inhibitory activity was also eluted from such a column. However, it was present in preparations obtained not only from CTL and NK cells, but also from some perforin-susceptible tumor cell lines, indicating that it has nonrestricted distribution and suggesting that it is probably irrelevant to the perforin-protection mechanism. Our results argue against a role for soluble granule HRF or other soluble factors in mediating resistance of cytotoxic lymphocytes against perforin-mediated lysis.

Animals↗

PubMed1982

[On the different release kinetics of water-soluble and lipid-soluble forms of hydroxyquinoline in oleogel ointment bases (author's transl)].

Studies using the model according to Horsch and Kögel showed that the release kinetics of the suspended water-soluble (but not lipid-soluble) drugs hydroxyquinoline sulphate and hydroxy-quinoline sulphate--potassium sulphate from oleogels is of a zero order. Differences in drug dispersity do not affect the release rates. Oleogels containing the lipid-soluble hydroxyquinoline base yielded undersaturated solution ointments, the release kinetics of which can be stated by a semilogarithmic relationship. There exists a linear correlation between the release rates and the product of the lipid solubility of the drug and the reciprocal apparent distribution coefficient.

Chemistry, Pharmaceutical↗

PubMed1997

Neutrophil Fc gamma and complement receptors involved in binding soluble IgG immune complexes and in specific granule release induced by soluble IgG immune complexes.

We examined the effect of soluble IgG immune complex (IC) characteristics on the binding of IC to human neutrophils and IC-induced specific granule release of neutrophils via Fc gamma receptors (CD16 and CD32) and complement receptors (CR1 and CR3). A set of soluble IgG IC varying in size, IgG subclass, antigen epitope density and complement (C) incorporation were formed between 5-iodo-4-hydroxy-3-nitrophenacetyl (NIP) coupled to bovine serum albumin (BSA) and chimeric mouse-human anti-NIP monoclonal antibodies (mAb) of all four IgG subclasses. High and low epitope density IC of all four IgG subclasses induced specific granule release with C, but in the absence of C only IgG1 and IgG3 IC were functionally active. The Fc gamma and C receptors responsible for IgG IC-induced specific granule release and IC binding were determined using mAb specific for the ligand binding sites of CD16, CD32 and CR3, and recombinant soluble CR1. Each defined IC displayed a unique pattern of receptor preference, dependent upon subclass and antigenic epitope density. IC binding and IC-induced specific granule release was not mediated by the same receptor, or combination of receptors. High and low epitope density IgG3 IC binding and induction of specific granule release was mediated predominantly via CD16. Other IC subclasses bound differently, i.e. IgG1 IC used CD16 and CR3; IgG2 and IgG4 predominantly used complement receptors; but all three induced specific granule release via CD32. In vivo these results may translate into differential activation of neutrophils by soluble IC dependent upon their characteristics, leading to subtle nuances in the etiology, pathology and control of the immune response in IC-related diseases.

Animals↗

PubMed2000

Distribution of lipid-soluble antioxidants in lipoproteins from healthy subjects. I. Correlation with plasma antioxidant levels and composition of lipoproteins.

The concentration of five lipid-soluble antioxidants (gamma- and alpha-tocopherol, lycopene, beta-carotene and ubiquinol-10) was measured in plasma and very low-density, low-density and high-density lipoproteins (VLDL, LDL and HDL) isolated from young healthy normo- cholesterolemic subjects. Alpha-tocopherol was the exclusive antioxidant whose plasma concentration significantly correlated with the absolute concentration of total cholesterol (r =0.541, P<0.001). No correlation was found between plasma concentration and lipoprotein content of alpha-tocopherol and ubiquinol-10, whereas it reached statistically significant values for gamma-tocopherol, lycopene and beta-carotene. The alpha-tocopherol content in VLDL and HDL, but not in LDL, was strictly associated with the relative abundance of cholesterol and phospholipids in the lipoprotein particles. Moreover, the difference between alpha-tocopherol concentration in VLDL and LDL appeared to be strictly related to the differences in cholesterol, phospholipids and triglycerides. The percent distribution of the total plasma pool of antioxidant in each lipoprotein class revealed that gamma- and alpha-tocopherol were roughly equally distributed in LDL and HDL. On the other hand, lycopene, beta-carotene and ubiquinol-10 were preferentially sequestered in LDL. Finally, the absolute and relative concentration of alpha-tocopherol, but not that of other antioxidants, in HDL exhibited a statistically significant correlation with plasma HDL/LDL cholesterol ratio. These findings indicate that: (i) plasma concentrations of major lipid-soluble antioxidants are not always predictive of their levels in lipoproteins and that, within individual lipoprotein classes, (ii) the lipid composition, metabolism and relative plasma concentration may significantly affect their abundance.

Adult↗

PubMed1994

Development of an ELISA assay for soluble CD35 (C3b/C4b receptor): high levels of soluble CD35 in LE-positive patients with hematological malignancies.

Malignant cells usually lack CD35 (complement receptor type 1, C3b/C4b receptor), a differentiation surface antigen. We measured soluble forms of CD35 in the plasma of normal subjects and patients with various malignant diseases. A microassay for the determination of CD35 was established based on a sandwich enzyme immunoassay using 2 monoclonal antibodies that recognize different epitopes. Soluble CD35 was not detected in any plasma samples from normal subjects or from patients with a variety of solid cancers: i.e., levels were below 20 ng/ml. On the other hand, 3 of 70 patients with hematological malignancies showed high levels of plasma CD35. The molecular mass of the soluble form was about 200 kDa, which is similar in size to membrane forms of CD35. Although the clinical conditions differed in these patients, they had high transaminase titers and detectable autoantibody. Complement titers (CH50) and the levels of membrane complement regulatory proteins were within the normal range in these patients. Although the mechanism by which it is produced remains unknown, soluble CD35 is present in significant amounts in association with immunological disorders secondary to hematological malignancies.

Enzyme-Linked Immunosorbent Assay↗

PubMed2002

The effect of MgO on the solubility behavior and cell proliferation in a quaternary soluble phosphate based glass system.

This paper presents a systematic study of the MgO-CaO-Na(2)O-P(2)O(5) glass system, which has great potential to be used as temporary hard and soft tissue implant materials. An overall study of solubility behavior of ternary and quaternary-based phosphate glass system have been carried out in order to understand the out-leaching progress of different ions and to determine their effect on cell proliferation. Originally, soluble phosphate based glasses within the ternary glass system of Na(2)O-CaO-P(2)O(5) have been developed to create a simple baseline system. This paper, however, presents the development of this system by introducing magnesium oxide as a partial calcium oxide substitute and solubility behaviors as well as cell studies have been carried out to check the effect on magnesium ions. Glasses have been prepared via standard glass melting techniques and their solubility behavior has been tested in distilled water via simple weight loss, pH and ion measurements. The way the glasses dissolve is an inverse exponential behavior which is mirrored by the calcium ion release. Other ions show a less exponential behavior. The MTT test has been used to check preliminary in vitro studies on a human MG63 cell line and the result indicates that cell proliferation is increased for glasses with minimal CaO substitution.

Journal Article↗

PubMed1996

Kinetics of soluble TNF-receptors and soluble adhesion molecules ICAM-1, E-selectin and VCAM-1 under systemic rhTNF alpha therapy.

Cytostatic as well as cytotoxic effects of tumour necrosis factor alpha (TNF-alpha) therapy have been shown in vitro and in experimental in vivo models. Nevertheless, the mechanism of anti-tumour activity in humans in vivo remains unclear. To determine the role of the vascular lining endothelial cells as important mediators of several immunological interactions, we investigated changes in the levels of the soluble endothelial cell adhesion molecules intercellular adhesion molecule 1, E-selectin and vascular cell adhesion molecule 1 as well as of soluble TNF receptors I and II during systemic therapy with recombinant human rhTNF-alpha (rhTNF-alpha). All tests were performed by enzyme-linked immunosorbent assays (ELISAs). The clinical efficacy of the intravenous rhTNF-alpha therapy was poor. Only one patient with isolated intraarterial limb perfusion had a delayed, marked, but only temporary necrosis of tumour cells. In contrast, we found a marked, significant and (during therapy) undulating augmented increase in the levels of soluble adhesion molecules as well as of the soluble TNF receptors. Taken together, these data support the hypothesis that a sufficient tumour-specific cellular immunity is required to achieve a clinically apparent efficacy of systemic rhTNF-alpha therapy in addition to cytokine-dependent inducible activation mechanisms. In this context, the vascular lining endothelial cells might play an important role as mediators of the complex immunological antitumoral activity.

Adult↗

PubMed1996

Direct binding of a soluble natural killer cell inhibitory receptor to a soluble human leukocyte antigen-Cw4 class I major histocompatibility complex molecule.

Natural killer (NK) cells expressing specific p58 NK receptors are inhibited from lysing target cells that express human leukocyte antigen (HLA)-C class I major histocompatibility complex molecules. To investigate the interaction between p58 NK receptors and HLA-Cw4, the extracellular domain of the p58 NK receptor specific for HLA-Cw4 was overexpressed in Escherichia coli and refolded from purified inclusion bodies. The refolded NK receptor is a monomer in solution. It interacts specifically with HLA-Cw4, blocking the binding of a p58-Ig fusion protein to HLA-Cw4-expressing cells, but does not block the binding of a p58-Ig fusion protein specific for HLA-Cw3 to HLA-Cw3-expressing cells. The bacterially expressed extracellular domain of HLA-Cw4 heavy chain and beta2-microglobulin were refolded in the presence of a HLA-Cw4-specific peptide. Direct binding between the soluble p58 NK receptor and the soluble HLA-Cw4-peptide complex was observed by native gel electrophoresis. Titration binding assays show that soluble monomeric receptor forms a 1:1 complex with HLA-Cw4, independent of the presence of Zn2+. The formation of complexes between soluble, recombinant molecules indicates that HLA-Cw4 is sufficient for specific ligation by the NK receptor and that neither glycoprotein requires carbohydrate for the interaction.

Amino Acid Sequence↗

PubMed1983

Soluble compound electron microscope (EM) autoradiography: a resolution source to test redistribution of soluble tritiated compounds during processing.

The development of a resolution source that can be labeled with either a soluble or insoluble tritiated compound, and of a method for applying a dry, uniform monolayer of emulsion is reported. Influences due to redistribution of the soluble isotope during emulsion coating were measured by comparing the grain density distributions around the resolution source for soluble tritiated proline (3H-PRO) with that obtained for cross-linked tritiated bovine serum albumin (3H-BSA). The grain density distributions resulting from a standard method of emulsion application (partly gelled/loop method) are compared to that obtained from a dry stripping film. It was found that only the dry stripping film gave a grain distribution which was statistically not different for the soluble and insoluble specimens.

Autoradiography↗

PubMed2000

Interleukin-1 receptor antagonist, soluble tumor necrosis factor-alpha receptor type I and II, and soluble E-selectin serum levels in multiple sclerosis patients receiving weekly intramuscular injections of interferon-beta1a.

BACKGROUND: interferon beta (IFN-beta) reduces relapse rate and disease progression in patients with the relapsing-remitting form of multiple sclerosis (RRMS). IFN-beta may act by upregulating the expression of anti-inflammatory components of the immune system. OBJECTIVES: To determine whether weekly intramuscular (i.m.) injection of IFN-beta1a had a short- or long-term effect on the expression of naturally occurring soluble factors that play an immunosuppressive role within the cytokine network. MATERIALS AND METHODS: serum levels of interleukin-1 receptor antagonist (IL-1Ra), soluble tumor necrosis factor alpha receptor type I and type II (sTNF-alphaRI and sTNF-alphaRII), and soluble E-selectin (sE-Sel) were followed over time in ten patients with RRMS who were treated with weekly i.m. injections of 30 mg (= 6 MU) of IFN-beta1a. Patient sera were sampled before, and 24, 48, 72, 96, and 168 hours after the first IFN-beta1a injection (short-term), and then at 1, 3, 6, 9 and 12 months after therapy initiation (long-term); highly sensitive, commercially available ELISA tests were used. RESULTS: serum levels of IL-1Ra, sTNF-alphaRI and sTNF-alphaRII, but not sE-Sel were significantly increased in both short- and long-term follow-up. Interestingly, IL-1Ra, sTNF-alphaRI and sTNF-alphaRII behaviors were completely different, suggesting that these naturally occurring immunoregulatory factors were differentially affected by IFN-beta1a. CONCLUSION: our study demonstrates that weekly i.m. injection of 30 mg of IFN-beta1a induces the expression of soluble mediators that may suppress the activities of pro-inflammatory cytokines such as IL-1 and TNF-alpha.

Adjuvants, Immunologic↗

PubMedDate not supplied

[Clinical course and changes of soluble interleukin-2 receptor and soluble forms of intercellular adhesion molecule-1 (ICAM-1) in serum of multiple sclerosis patients].

UNLABELLED: Changes were assessed in serum levels of soluble interleukin-2 receptor (sIL-2R alpha) and soluble intercellular adhesion molecule-1 (sICAM-1), indirect indices of activation of immunological system, in the course of multiple sclerosis (ms). 12 patients (av. age 39.2 +/- 9.4 y.) with the first relapse that fulfilled criteria of clinical probable ms acc. to Poser Committee were included into the study. Blood samples were taken at the beginning of the relapse and then every 2-month periods. Simultaneously, neurological impairment (EDSS scale) was assessed. When the next relapse occurred examination was repeated from the beginning. The total time of observation was between 12 and 18 months. The levels of both soluble molecules were examined with ELISA test. In relapse mean serum levels of sIL-2R alpha and sICAM-1 were significantly elevated in comparison to the results obtained in remission (respectively: p < 0.001 and p = 0.03). Changes in serum level of both soluble molecules during the first 2 months after relapse were significantly higher than in subsequent 2-month periods (p < 0.001). Each relapse was accompanied by elevation of serum levels of sIL-2R alpha and sICAM-1. There was no obtainable correlation between improvement in EDSS scale and changes in sIL-2R alpha level during the whole time of observation. Improvement in EDSS scale was correlated with lowering of sICAM-1 but only during the first two months after relapse. CONCLUSIONS: Serum level of sIL-2R alpha and sICAM-1 in ms patients during relapse is significantly higher in comparison to the results obtained during remission. Each relapse is accompanied by elevation of sIL-2R alpha and sICAM-1 in serum, during remission serum levels of both molecules do not changed significantly.

Adult↗

PubMed1995

Change of water-soluble-protein, urea-soluble-protein and membrane intrinsic protein in human senile cataract.

PURPOSE: To analyze the change of water-soluble-protein (WSP), urea-soluble-protein (USP) and membrane intrinsic protein (MIP) in human senile cataract. METHODS: The water-soluble-fractions (WSF) were prepared basically according to the method of Kibbelear, et al. But in this study, 5 mmol/L B-mercaptoethanol was added to the buffer solution. The urea-soluble-fractions (USF) were prepared basically according to the method of Kibbelear, et al. Lens fiber cell membranes were purified basically according to the method of Russell, et al. SDS-PAGE were performed according to the procedure of Laemmili, et al. using resolving gel 13% and 3% stacking gel. RESULTS: The WSP was fractionated into HM+ alpha-, beta(1-3)- and gamma-crystallin components. In nuclear cataractous lenses HM+ alpha- and B-crystallin increase, while r-crystallin decrease. The USP from clear lenses contains mainly alpha beta chains of 22KD, whereas in cataractous lenses, especially in nuclear cataractous lenses, the relative amount of the 28- and 23KD polypeptide (the components of beta-crystallin) increased markedly. Lens fiber cell MIP, clear lens and cataract lens contained the main polypeptide of 27KD (MIP) and 23KD (MP23). CONCLUSION: The water-insoluble protein, whether in quantity or in quality, plays an important role in cataract formation.

Aged↗

PubMed2003

Enhanced solubility of paclitaxel using water-soluble and biocompatible 2-methacryloyloxyethyl phosphorylcholine polymers.

The purpose of this study was to enhance the water-solubility of paclitaxel (PTX) using an amphiphilic 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer as the solubilizer. PTX is an antineoplastic drug effective for various cancers, especially for ovarian and breast cancers. However, its solubility in aqueous medium is quite low, less than 0.1 microg/mL in water. We prepared the amphiphilic MPC polymers containing hydrophobic units to form aggregates and provide hydrophobic domains in water. The most effective polymer to dissolve the PTX was poly[MPC-co-n-butyl methacrylate(BMA) (PMB30W)] with 70 mol % of the BMA unit. The inside polarity of PMB30W aggregate was the same as that of ethanol, which is a good solvent for dissolving PTX. The diameter of PMB30W aggregate containing 1 mg/mL of PTX was 50 nm in aqueous medium. The concentration of PTX in the PMB30W aqueous solution reached 5.0 mg/mL. The solution was transparent and PTX did not precipitate even when the solution was stored at room temperature for 1 month. Animal experiments indicated that the PMB30W has no adverse effect even when the polymer solution is injected into the bloodstream. From the PMB30W/PTX solution, we prepared by the solvent evaporation method a PMB30W film containing PTX with good transparency. The PMB30W film containing PTX easily dissolved in water to give a clear solution. We conclude that the water-soluble amphiphilic MPC polymers are good solubilizers for PTX as injectable and biocompatible drug formulations.

Antineoplastic Agents, Phytogenic↗

PubMed2003

Effect of hydrotalcite-like compounds on the aqueous solubility of some poorly water-soluble drugs.

A new approach of improving drug dissolution properties is described. This method exploits the property of a carrier owing to the hydrotalcite-type anionic clays (HTlc). HTlc is an inorganic layered solid that lodges anionic compounds among its layers. As HTlc dissolves at acidic pH values (pH < 4), the anions intercalated among the layers are promptly released in the medium. In this article some nonsteroidal antiinflammatory drugs were chosen as models of poorly water-soluble drugs. They were intercalated in HTlc and solubility measurements in acidic medium were performed. A remarkable improvement of drug solubility was observed especially in the case of indomethacin.

Aluminum Hydroxide↗

PubMed1982

Extended Hildebrand solubility approach: solubility of tolbutamide, acetohexamide, and sulfisomidine in binary solvent mixtures.

The extended Hildebrand approach for predicting solubilities of crystalline compounds in solvent mixtures was tested using tolbutamide, acetohexamide, and sulfisomidine in mixed solvents consisting of hexane-absolute ethanol and 95% (v/v) ethyl alcohol-aqueous buffer. The solubility of these drugs was determined at 25 +/- 0.2 degrees and then back-calculated using the adhesive energy term, W, to account for solute-solvent interaction. Solubilities were predicted within 13% for tolbutamide, 31% for acetohexamide, and 43% for sulfisomidine, and with considerably better accuracy in most solvent mixtures.

Acetohexamide↗

PubMed1988

Solubility and partitioning. IX: Solubility of hydantoins in water.

An expression for estimating the aqueous solubility of weak electrolytes under different conditions of temperature and pH has been proposed in a previous publication. The expression, based on the additivity of free energy, separates solubility into three independent contributions. In the present work, the equation is tested with a different set of 18 solutes within the range of temperature of 20 to 50 degrees C and of pH of 1 to 10. The results show that the theoretical relationship between aqueous solubility and the three independent contributions used in the equation is in excellent agreement with the experimental data.

Chemical Phenomena↗