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PubMed2006

Anti-histamines for prolonged non-specific cough in children.

BACKGROUND: Non-specific cough is defined as non-productive cough in the absence of identifiable respiratory disease or known aetiology. It is commonly seen in paediatric practice. These children are treated with a variety of therapies including anti-histamines. Also, anti-histamines are advocated as an empirical treatment in adults with chronic cough. OBJECTIVES: To evaluate the effectiveness of anti-histamines in treating children with prolonged non-specific cough. SEARCH STRATEGY: The Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, OLDMEDLINE and EMBASE databases were searched by the Cochrane Airways Group. The latest searches were performed in November 2005. SELECTION CRITERIA: All randomised controlled trials comparing anti-histamines with a placebo or placebo-like medication with cough as an outcome, where cough is not primarily related to an underlying respiratory disorder such as cystic fibrosis, asthma, or suppurative lung disease. DATA COLLECTION AND ANALYSIS: Results of searches were reviewed against pre-determined criteria for inclusion. Two independent reviewers selected, extracted and assessed data for inclusion. Three eligible trials were identified. MAIN RESULTS: The three included studies varied in age of subjects, sample size, inclusion criteria, type of anti-histamine and length of intervention. These 3 studies included 182 randomised subjects with 162 completing the trials although in one study, children with recurrent wheeze were also included. Clinical heterogeneity was evident and limited data prevented combining data for meta-analysis. The two larger studies described significant improvement in both the intervention and the placebo/placebo-like arms with no significant difference between the two groups. In the study with the smallest sample size, cetirizine (a second generation anti-histamine) was significantly more efficacious than placebo in reducing chronic cough in children associated with seasonal allergic rhinitis, and the effect was seen within 2 weeks of therapy. AUTHORS' CONCLUSIONS: This review has significant limitations. However, our finding of uncertain efficacy of anti-histamines for chronic cough are similar to that for acute cough in children. In contrast to recommendations in adults with chronic cough, anti-histamines cannot be recommended as empirical therapy for children with chronic cough. If anti-histamines were to be trialled in these children, current data suggest a clinical response (time to response) occurs within 2 weeks of therapy. However the use of anti-histamines in children with non-specific cough has to be balanced against the well known risk of adverse events especially in very young children.

Child↗

PubMed2001

Highly selective guest uptake in a silver sulfonate network imparted by a tetragonal to triclinic shift in the solid state.

The silver sulfonate network presented herein, silver 3-pyridinesulfonate, reversibly and selectively absorbs MeCN while undergoing a major structural rearrangement. The origin of this structural flexibility is a coupling of the weak coordinating ability of the SO3 group with the geometrically pliant silver(I) center. Single crystal and powder X-ray structures of both the desolvated and solvated forms are presented in addition to the mechanism of their reversible interconversion. A heterogeneous gas chromatographic study showing selective extraction of the MeCN is also presented. Extended solid frameworks which reorder to any extent are not common but the structure presented herein transforms from a tetragonal to a triclinic crystal system. The results indicate that cooperative interactions in systems based on supposedly weaker interactions can yield softer yet functional networks with behavior unlike that observed in more rigid inorganic frameworks.

Journal Article↗

PubMed2002

Proteomic analysis of human biopsy samples by single two-dimensional electrophoresis: Coomassie, silver, mass spectrometry, and Western blotting.

Proteomic analysis of myocardial tissue from patient populations is critical to our understanding of cardiac disease, but has been limited until now by the small size of biopsies (approximately 20-50 microg), and complicated by the difference in relative abundance of contractile proteins over other cellular components. Here we describe an approach to analysis of myocardial biopsies from patients undergoing coronary artery bypass surgery. First, individual biopsies are selectively extracted, producing subfractions that correspond to the contractile proteins and the cytosolic proteins. Two-dimensional electrophoresis separated proteins are detected by first staining with Coomassie blue then silver, to permit a wider range of accurate quantification. Western blotting of two-dimensional separated samples, to validate peptide mass fingerprinting data, previously required additional gel separations for transfer since staining protocols are not compatible with transfer to membranes or immunoblotting. An existing silver destaining protocol was adapted to allow removal of silver from a whole gel, followed by transfer and Western blotting. An existing Coomassie blue removal protocol was also adapted to permit Western blotting of gels stained with Coomassie blue and silver. Together, these techniques permit peptide mass fingerprinting concurrent with Western blotting of a single protein spot from a single biopsy, eliminating the need for repeated gel separations, and improving spot alignment between immunoblots and stained gels. In the end, this approach may allow a more complete characterization of protein changes in small human biopsies, and also reduce the number of repeated gel separations necessary for a standard proteomic analysis.

Animals↗

PubMed1990

Effects of tooth function on adjacent alveolar bone and Sharpey's fibers of the rat periodontium.

There is little information about the effects of short-term non-hypo-, and hyperfunction of teeth on the 1) mineralization patterns of intrinsic and extrinsic (Sharpey's) fibers and 2) mean number and diameter of Sharpey's fibers of adjacent alveolar bone. The mineral density of intrinsic and Sharpey's fibers and the size and number of Sharpey's fibers could indicate the relative strength of the attachment of a tooth to bone in various functional situations. In the present study, non- and hypofunctional situations were created by selective extraction of right molar teeth of the rat; the contralateral teeth were placed in hyperfunction by the surgery. In non- and hypofunctionals, intrinsic and Sharpey's fibers of the crestal third of the alveolus were less densely mineralized than in hyperfunctionals or untreated controls. Mean Sharpey's fiber diameters were significantly greater and their mean number/unit area significantly less in non- than in hypo- or hyperfunctionals or untreated controls (P less than 0.001). Mean Sharpey's fiber diameters in hyperfunctionals were significantly less than in untreated controls (P less than 0.05). Hypofunction ameliorated the effects of nonfunction on mean diameter and number of Sharpey's fibers, but had little effect on the density of mineralization of either the intrinsic or Sharpey's fibers of the alveolus, suggesting that their mineralization may be controlled by factors other than occlusal forces from the adjacent teeth. Thus changes in the stress/strain environment within the periodontium, coincident to altered occlusal function of the adjacent teeth, rapidly affects the morphology of intrinsic and Sharpey's fibers of alveolar bone and ensures that adequate tooth support is maintained in the new functional situation.

Alveolar Process↗

PubMed2001

Kinetic resolution of chiral amines with omega-transaminase using an enzyme-membrane reactor.

A kinetic resolution process for the production of chiral amines was developed using an enzyme-membrane reactor (EMR) and a hollow-fiber membrane contactor with (S)-specific omega-transaminases (omega-TA) from Vibrio fluvialis JS17 and Bacillus thuringiensis JS64. The substrate solution containing racemic amine and pyruvate was recirculated through the EMR and inhibitory ketone product was selectively extracted by the membrane contactor until enantiomeric excess of (R)-amine exceeded 95%. Using the reactor set-up with flat membrane reactor (10-mL working volume), kinetic resolutions of alpha-methylbenzylamine (alpha-MBA) and 1-aminotetralin (200 mM, 50 mL) were carried out. During the operation, concentration of ketone product, i.e., acetophenone or alpha-tetralone, in a substrate reservoir was maintained below 0.1 mM, suggesting efficient removal of the inhibitory ketone by the membrane contactor. After 47 and 32.5 h of operation using 5 U/mL of enzyme, 98.0 and 95.5% ee of (R)-alpha-MBA and (R)-1-aminotetralin were obtained at 49.5 and 48.8% of conversion, respectively. A hollow-fiber membrane reactor (39-mL working volume) was used for a preparative-scale kinetic resolution of 1-aminotetralin (200 mM, 1 L). After 133 h of operation, enantiomeric excess reached 95.6% and 14.3 g of (R)-1-aminotetralin was recovered (97.4% of yield). Mathematical modeling of the EMR process including the membrane contactor was performed to evaluate the effect of residence time. The simulation results suggest that residence time should be short to maintain the concentration of the ketone product in EMR sufficiently low so as to decrease conversion per cycle and, in turn, reduce the inhibition of the omega-TA activity.

Amines↗

PubMed1987

Identification and quantification of arsenocholine and acetylarsenocholine in trace amounts in biological material by use of pyrolysis gas chromatography/mass spectrometry.

An analytical method, based on a selective extraction and pyrolysis gas chromatography/mass spectrometry assay of arsenocholine and acetylarsenocholine in aquatic organisms, is described. Characteristic fragmentation patterns were obtained from pyrolytically demethylated compounds. The molecules were rearranged in unique pathways which differed from those of corresponding nitrogen analogues. Qualitative determination of arsenocholine and acetylarsenocholine was achieved by gas chromatographic as well as mass spectrometric analysis of the thermal degradation products (trimethylarsine, dimethylvinylarsine and the demethylated arsenocholine or acetylarsenocholine). Arsenocholine and acetylarsenocholine in fish from industrially polluted water were isolated and identified. Massfragmentographic quantification of the arsenic compounds in fish was carried out by use of deuterium labelled analogues of arsenocholine and acetylarsenocholine as internal standards. The method showed a high sensitivity.

Animals↗

PubMed2006

Individual dissolution of single-walled carbon nanotubes in aqueous solutions of steroid or sugar compounds and their Raman and near-IR spectral properties.

The individual solubilization of single-walled carbon nanotubes (SWNTs), achieved by using ten different anionic-, zwitterionic-, and nonionic-steroid biosurfactants and three different sugar biosurfactants, was examined. Aqueous micelles of anionic cholate analogues, such as sodium cholate (SC), sodium deoxycholate (SDC), sodium taurocholate (STC), sodium taurodeoxycholate (STDC), sodium glycocholate (SGC), as well as N,N-bis(3-D-gluconamidopropyl)cholamide (BIGCHAP) and N,N-bis(3-D-gluconamidopropyl)deoxycholamide (deoxy-BIGCHAP), exhibited good abilities to dissolve the SWNTs individually. Aqueous micelles of nonionic biosurfactants, such as sucrose monocholate (SMC), n-octyl-beta-D-glucoside (OG), n-decyl-beta-D-maltoside (DM), and n-decanoyl-N-methylglucamide (MEGA-10), could dissolve the SWNTs, however, the solubilization abilities were weaker than those of the anionic cholate analogues. In sharp contrast, the solubilization abilities of the zwitterionic micelles of 3-[(3-cholamidopropyl)dimethylammonio]propanesulfonic acid (CHAPS) and 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxypropanesulfonic acid (CHAPSO) were very low, and almost zero for OG. It is evident that the chemical structures, in particular the substituent groups of the surfactants, play an important role in the solubilization of SWNTs. The near-IR photoluminescence behaviors of the SWNTs dissolved in aqueous micelles and in 1 mM biosurfactants were investigated. The chirality indices of the SWNTs dissolved in these solutions depend on the chemical structures of the biosurfactants. The Raman spectra of the SWNTs dissolved in a 1 mM solution of SC suggest the selective extraction of the metallic SWNTs. Finally, a possible solubilization mechanism using steroid surfactants is described. The SWNTs dissolved individually in water-containing biocompounds are useful in many areas of nano- and materials chemistry.

Journal Article↗

PubMedDate not supplied

Complex protein composition of isolated focal adhesions: a two-dimensional gel and database analysis.

Current ideas about the composition of the focal adhesion complexes in cultured cells are based mainly on indirect immunocytochemical data. We here report a two-dimensional (2-D) gel electrophoresis analysis of the focal adhesion associated-structures that remain in the growth substrate after removal of cells by mechanical shearing. Many proteins additional to the known adhesion proteins, and in higher abundance, could be identified. Using selective extraction procedures, employing detergent or gelsolin, these could be classified as either membrane-associated, actin-associated or both. Cross correlation of these polypeptode patterns with a 2-D gel database allowed identification of some proteins, not previously considered as resident of focal adhesions. The data point to a more complex make up of focal adhesions than formerly supposed.

3T3 Cells↗

PubMed1997

Generation of proteoliposomes from subcellular fractions.

Intracellular membranes are highly dynamic, yet they retain their identity and functional characteristics. Integral membrane proteins, which must confer this specific membrane identity, remain poorly characterized at the biochemical level, largely because detergent-mediated solubilization is required for purification and analysis, and several properties of integral membrane proteins can only be investigated when the molecule is properly embedded in a lipid bilayer. We present a method for the efficient reconstitution into proteoliposomes of integral membrane proteins from subcellular fractions. Integral membrane proteins were identified on high-resolution two-dimensional gels after selective extraction of soluble and peripheral membrane proteins; they accounted for 8% of the number of resolved polypeptides. A reconstitution procedure based on membrane solubilization with dodecyl-octaoxyethylene (C12E8) and subsequent detergent removal with BioBeads SM-2 resulted in the efficient reconstitution of several membrane proteins into proteoliposomes of uniform density. The generated proteoliposomes strongly resemble the starting membrane fraction in protein composition. This reconstitution allows the functional characterization of integral membrane proteins after enrichment and/or specific (immuno)depletion.

Animals↗

PubMed1989

Synthesis and adsorption of a poly(N-acetylethyleneimine)-polyethyleneoxide-poly (N-acetylethyleneimine) triblock-copolymer at a silica/solution interface. Influence of its preadsorption on platelet adhesion and fibrinogen adsorption.

The synthesis of a triblock copolymer poly-(N-acetylethyleneimine)-polyethylenoxide-poly(N-acet ylethyleneimine) includes two successive steps: the first is the functionalization of a poly(ethyleneglycol) precursor by creating sulfonic esters at its chain ends, the second uses these esters to initiate the cationic polymerization of 2-methyl-2-oxazoline. Homopolymers appear in the raw product; hence successive selective extractions of the copolymer with benzene and dioxane are necessary. The final yield in pure copolymer was 11%. The copolymer was characterized by UV and 1H-NMR spectrometry and light scattering. Adsorption isotherms were determined on silica, for varying pH and salt concentration. Optimum conditions for coating silica with the polymer were determined. The efficiency of this precoating to reduce the adsorption of fibrinogen was very high (99.2% reduction with respect to bare silica). Steric exclusion chromatography of a variety of proteins gave a satisfactory calibration curve. Platelet accumulation on copolymer precoated glass was reduced to 10-20% of its value on bare glass, a result superior to that obtained by albumin passivation of the same glass surface.

Adsorption↗

PubMed2003

Role of elastin in pathologic calcification of xenograft heart valves.

Bioprosthetic heart valves fabricated from glutaraldehyde crosslinked porcine aortic valves often fail because of calcific degeneration. Calcification occurs in both cusp and aortic wall portions of bioprosthetic heart valves. The purpose of this study was to discern the role of different aortic wall components in the calcification process. Thus, we selectively extracted cells and other extracellular matrix proteins from porcine aorta using trypsin/DNase/RNase, cyanogen bromide (CNBr), and sodium hydroxide (NaOH) treatments and subdermally implanted these pretreated aortas in young rats. Total DNA and phospholipid data showed complete removal of cells by CNBr and NaOH treatments, whereas trypsin/DNase/RNase treatment was effective in removing DNA but not phospholipids. As shown by amino acid data and Masson's trichrome staining, collagen was removed in CNBr and NaOH treatments. Control fresh porcine aorta calcified significantly after 21 days of implantation (Ca 26.4 +/- 2.4 microg/mg). Removal of cells and collagen from the aorta by CNBr treatment did not lead to a statistically significant reduction in aortic calcification (Ca 20.8 +/- 3.0 microg/mg). Moreover, partial degradation of elastin fibers caused by NaOH (during extraction) and trypsin treatment (after implantation) of the aorta significantly increased elastin-oriented calcification (Ca 94.4 +/- 9.3 and 58.4 +/- 4.6 microg/mg, respectively). Our results indicate that the elastin component of the aorta may undergo independent calcification irrespective of devitalized cell-mediated calcification observed in glutaraldehyde crosslinked aortas. Our results also demonstrate the importance of studying elastin-oriented calcification in decellularized elastin-rich aortic matrices currently used in tissue-engineering applications.

Amino Acids↗

PubMed1995

Cartilage oligomeric matrix protein: isolation and characterization from human articular cartilage.

Cartilage oligomeric matrix protein was purified in a native form from normal adult human articular cartilage. The key steps in the purification scheme were selective extraction with buffer containing EDTA, wheat germ agglutinin affinity chromatography, and removal of the related protein thrombospondin by heparin affinity chromatography. Particles of cartilage oligomeric matrix protein viewed by electron microscopy after rotary shadowing revealed structures similar to the prototype molecule purified from Swarm rat chondrosarcoma. The protein demonstrated a bouquet-like five-armed structure, with peripheral globular domains connected by thin flexible strands to a central assembly domain. Immunohistochemistry revealed age-dependent differences in the protein's distribution in cartilage. In normal human adult articular cartilage, there was a relatively uniform distribution throughout the interterritorial extracellular matrix, whereas in fetal articular cartilage, immunostaining was localized to the extracellular matrix directly adjacent to the chondrocytes. The isolation and characterization of human cartilage oligomeric matrix protein will facilitate its study in pathological conditions of human cartilage.

Adult↗

PubMed2002

Mechanism of lidocaine release from carbomer-lidocaine hydrogels.

Rheology, acid-base behavior, and kinetics of lidocaine release of carbomer-lidocaine (C-L) hydrogels are reported. A series of (C-L)(x) (x = mol% of L = 25, 50, 75, 100) that covers a pH range between 5.33 and 7.96 was used. Concentrations of ion pair ([R-COO(-)LH(+)]) and free species (L) and (LH(+)) were determined by the selective extraction of (L) with cyclohexane (CH) together with pH measurements, i.e., CH in a ratio CH/hydrogel 2:1 extracted 48% of the whole concentration of lidocaine [L(T)] of a (C-L)(100), [[L(T)] = ([R-COO(-)LH(+)]) + (L) + (LH(+))]. The remaining species in the aqueous phase were distributed as: (L) 3.82%, (LH(+)) 14.5%, and [R-COO(-) LH(+)] 81.7%. Rheology and pH as a function of (C-L) concentration are also reported. Delivery rates of free base L were measured in a Franz-type bicompartmental device using water and NaCl 0.9% solution as receptor media. (C-L) hydrogels behave as a reservoir that releases the drug at a slow rate. pH effects on rate suggest that, under the main conditions assayed, dissociation of [R-COO(-)LH(+)] is the slow step that controls releasing rates. Accordingly, release rate was increased upon addition of a second counterion (i.e., Na(+)), or through the diffusion of neutral salts such as NaCl, into the matrix of the gel.

Acrylic Resins↗

PubMed1975

GLC determination of plasma drug levels after oral administration of clorazepate potassium salts.

Plasma nordiazepam levels resulting from the oral administration of clorazepate potassium salts were determined by a sensitive GLC assay. Nordiazepam and the internal standard (diazepam) were selectively extracted into ether at pH 9.2, hydrolyzed to their respective benzophenones, and quantified by electron-capture detection. The assay was used in a comparative bioavailability study of single equimolar oral doses of monopotassium and dipotassium salts of clorazepate in dogs. Both clorazepate salts were rapidly absorbed and exhibited mean peak total drug levels after 1 hr. Clorazepate levels accounted for about 50% of the total drug levels present. No statistical difference in the plasma drug levels of clorazepate mono- and dipotassium salts and the metabolite was found in dogs.

Administration, Oral↗

PubMed1976

Determination of nitroimidazoles in biological fluids by differential pulse polarography.

A sensitive differential pulse polarographic assay was developed for the determination of metronidazole, ornidazole, and 2-nitro-1H-imidazole-1-(3-methoxy-2-propanol) in plasma. The compounds are selectively extracted into ethyl acetate from a protein-free filtrate of plasma, buffered to pH 7.0 +/- 0.2. The residue of the ethyl acetate extract is dissolved in 0.1 N NaOH and analyzed by differential pulse polarography for the reduction of the nitro group at approximately -0.600 v versus the saturated calomel electrode. The overall recovery from plasma was about 55 +/- 3.0% (SD) for the three compounds investigated. A TLC step after the ethyl acetate extraction may also be included to ensure specificity. This step reduced the overall recovery to approximately 45%. The sensitivity limit of detection from plasma using a 2-ml sample is 0.1 mug/ml. The assay may also be employed for the analysis of urine. The urine is adjusted to pH 7.0 +/- 0.2 and extracted with ethyl acetate, and the residue is analyzed as described for plasma. The assay was applied to the determination of ornidazole in blood and urine in the dog following 10 mg/kg po.

Animals↗

PubMed1977

High-pressure liquid chromatographic analysis of drugs in biological fluids II: determination of an antiarrhythmic drug, tocainide, as its dansyl derivative using a fluorescence detector.

A sensitive and specific method is described for the determination of a new primary aliphatic amine antiarrhythmic drug, tocainide. Tocainide, together with an internal standard, is selectively extracted from plasma or blood and reacted with dansyl chloride. The highly fluorescent dansyl derivatives are separated using high-pressure liquid chromatography and measured using a fluorescence detector. The method can measure therapeutic and subtherapeutic concentrations of the drug (0.1-5.0 microng/ml of plasma) with a standard deviation of less than 2%.

Anilides↗

PubMed1977

Determination of an anti-inflammatory methanesulfonanilide in plasma by high-speed liquid chromatography.

A sensitive and chemically specific high-speed liquid chromatographic method was developed for the determination of 4-nitro 2-phenoxymethanesulfonanilide in plasma. The method includes selective extraction of the anti-inflammatory drug and an internal standard, 2-(4'-chlorophenoxy)-4-nitromethanesulfonanilide, into benzene from acidified plasma followed by reextraction into 0.2 N NaOH. The aqueous layer is acidified, and the drug is reextracted into benzene. The benzene is evaporated, and the residue is dissolved in a small volume of acetonitrile. A 10-microliter aliquot is analyzed on a reversed-phase column. The mean overall extraction recovery, after correction for aliquot factors, is 99%. The accuracy, expressed as the relative error, is 4, 0.3, and -3% at 0.60, 1.50, and 3.00 microgram/ml, respectively. Repeated analysis of reference standards indicates that the precision, expressed as the relative standard deviation, is 3% or less. The lower sensitivity limit is 0.2 microgram/ml with a 2-ml plasma sample. The method was applied successfully to the determination of plasma levels of 4-nitro-2-phenoxymethanesulfonanilide in humans and rats in metabolic experiments at pharmacological doses.

Animals↗

PubMed1978

Spectrofluorometric determination of alkoxy-substituted benzylimidazolidinones in biological fluids.

Sensitive and specific spectrofluorometric assays were developed for the determination of d, 1-4-(3,4-dimethoxybenzyl)-2-imidazolidinone and d,1-4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone in blood and urine. Each compound is selectively extracted from buffered blood or urine and oxidized with alkaline permanganate to its respective fluorescent benzoic acid derivative, which is quantitated in acetic acid in ethanol (1:99). The method was applied to the determination of blood levels and urinary excretion in the dog following the administration of single intravenous and oral doses of each compound.

Animals↗