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At least 667 records · Page 37Linked to original sources
PubMed2000

Comparable efficacy of administration with face mask or mouthpiece of nebulized budesonide inhalation suspension for infants and young children with persistent asthma.

A randomized, double-blind, placebo-controlled, parallel-group study including 481 children at 37 centers in the United States demonstrated the efficacy and safety of budesonide inhalation suspension in doses of 0.25 mg once daily, 0.25 mg twice daily, 0.5 mg twice daily, and 1.0 mg daily in infants and young children with persistent asthma. The retrospective analysis presented here compares the efficacy of treatment with the suspension administered through a face mask or mouthpiece. All patients receiving budesonide inhalation suspension via face mask or mouthpiece showed clinical improvements in nighttime and daytime asthma symptoms as compared with administration of a placebo. The improvements were of similar magnitude as those observed in an analysis of all patients treated. Improvements in nighttime asthma symptoms were statistically significant with budesonide at 0.25 mg daily (p = 0.040), 0.25 mg twice daily (p = 0.008), and 0.5 mg twice daily (p = 0.046) delivered by face mask. In patients using mouthpieces, nighttime asthma symptoms improved significantly in the 0.25-mg twice-daily (p = 0.005) and 1.0-mg daily (p = 0.035) groups. Patients receiving budesonide at 0.5 mg twice daily via a face mask improved significantly in daytime asthma symptoms (p = 0.009). The use of breakthrough medication was reduced in patients receiving budesonide via face masks or mouthpieces relative to placebo, and treatment was well tolerated in all study groups. This retrospective analysis suggests that nebulized budesonide inhalation suspension can be administered effectively by either face mask or mouthpiece to young children with persistent asthma.

Administration, Inhalation↗
PubMed1991

The safety, efficacy, and tolerability of cefuroxime axetil suspension in infants and children receiving previous intravenous antibiotic therapy.

The tolerability, safety, and efficacy of cefuroxime axetil suspension was studied in 36 children (aged 3 mo to 12 y) who had been hospitalized for respiratory tract or soft-tissue infections. After receiving parenteral antibiotics for a mean of 3.7 days, children were discharged home to receive cefuroxime axetil suspension at doses of 10, 15, or 20 mg/kg every 8 or 12 hours for a mean of 8.2 days. One child was lost to follow-up. Three of 35 evaluated patients were withdrawn from therapy because of adverse events, one of which was a drug-related hypersensitivity reaction. Of the 32 children who completed therapy, 9 developed mild reactions including oral thrush, diarrhea, or diaper dermatitis; none were withdrawn from therapy. Complete clinical cure occurred in 28 children (80 percent); 4 (11.4 percent) were clinically improved but still required an additional antibiotic within one week of completing therapy with cefuroxime axetil suspension. This favorable tolerability and safety of cefuroxime axetil suspension warrants further efficacy trials in pediatric patients.

Anti-Bacterial Agents↗
PubMed1995

Stability of hydrocortisone oral suspensions prepared from tablets and powder.

OBJECTIVE: To assess the stability, dosage uniformity, and clinical acceptability of hydrocortisone oral suspensions prepared from tablets and powder. DESIGN: Hydrocortisone 2.5 mg/mL oral suspensions were stored in the dark for 91 days at 5, 25, and 40 degrees C. Dosage uniformity was assessed by repeated sampling of the formulation prepared from tablets at 5 and 25 degrees C. The formulation was clinically evaluated in 2 pediatric patients. SETTING: A university pharmacy school and affiliated urban teaching hospital. PARTICIPANTS: A brother (4 y old) and sister (1 y old) with congenital adrenal hyperplasia maintained on a commercially available hydrocortisone cypionate suspension. MAIN OUTCOME MEASURES: Samples removed at 5 time points were analyzed for hydrocortisone to assess decomposition over 90 days. Dosage uniformity was evaluated by intra- and interday variability. Palatability was examined in the 2 children and urinary cortisol concentrations were measured in the boy before and 5 days after commencing the formulation prepared from tablets. RESULTS: Decomposition of hydrocortisone was not significant except in the formulation that was prepared from tablets and stored at 40 degrees C. Dosage uniformity gave coefficients of variation less than 4.5%. The formulation was well-tolerated and resulted in satisfactory urinary cortisol concentrations in the boy. CONCLUSIONS: The hydrocortisone oral suspensions supply a uniform dose and are chemically stable when stored in the dark at 5 and 25 degrees C for at least 30 days. They provide flexible and convenient dosage forms for pediatric patients.

Adrenal Hyperplasia, Congenital↗
PubMed1996

Estimations of average particle sizes and size distributions of commercially available human-insulin aqueous suspensions using laser-light diffraction spectroscopy.

The average diameter and size distribution of particles in commercially available isophane-insulin and zinc-insulin aqueous suspensions (11 products) were examined using laser-light diffraction spectroscopy (LLDS). Wide variation was observed between products in volume-weighted and number-weighted average diameters. The particles in the insulin aqueous suspensions were found to be mono-dispersed within relatively narrow size distributions. Sonication for a short time led to a downshift in the apparent average diameter, which was most remarkable with isophane-insulin aqueous suspensions. This could be ascribed to dispersion of aggregated needle-like crystals and/or crystal breakage. In the case of biphasic isophane-insulin aqueous suspensions, the average size as well as the size distribution shifted toward the smaller end of the scale with decrease in the isophane content.

Humans↗
PubMed2006

Effect of polyvinylpyrrolidone and sodium lauroyl isethionate on kaolinite suspension in an aqueous phase.

Suspension of concentrated kaolinite (20 g/30 ml-medium) in the presence of polyvinylpyrrolidone (PVP) and sodium lauroyl isethionate (SLI) was allowed to evaluate its degree of dispersion based on their rheological studies. Flow curves at low shear rate, measured by means of cone-plate method, showed a non-Newtonian flow. Plastic viscosity and Bingham yield value were derived from the flow curves. Relative viscosity, effective volume fraction and void fraction of secondary particle were also obtained. Results of dispersity and fluidity of the suspension were explained. PVP acted as a flocculant at a concentration lower than 0.1% but as a dispersant at a higher concentration. The presence of SLI could decrease both the Bingham yield value and suspension viscosity. Cooperative and competitive effects of PVP and SLI were found. Results indicated that SLI enhanced the degree of dispersion of kaolinite when PVP was less than 0.1%. The suspension, however, showed a maximum flocculation (i.e., aggregation) at 4 mM SLI when the concentration of PVP was higher than 0.1%.

Isethionic Acid↗
PubMed1989

An appropriate ingestion volume of oral sulfa drug suspension in pigs.

The influence of ingested volume of a sulfa drug suspension, sodium sulfamonomethoxine (SMMNa), on the oral pharmacokinetics was studied in pigs, with regard to bioavailability and gastric emptying. Eighteen pigs, weighing 30-70 kg, were used. Phenol red solution was used for the evaluation of gastric emptying study. SMMNa suspension was used for pharmacokinetic study. Both of these fluids were administered by natural swallowing. Three experimental groups were constructed: G-I; 5 ml/kg of the test fluids to starved animals, G-II; 5 ml/kg of the test fluids to fed animals and G-III; 20 ml/kg of the fluids to fed animals. The glucose glycine electrolyte solution (GGES) was used as the vehicle for both the compounds. Six pigs, having duodenal cannula, were used for the study of gastric emptying. The gastric emptying rate was rapid in G-I, relatively rapid in G-III, and slow and variable in G-II. In agreement with the result of gastric emptying study, the values of Cmax and tmax were high and rapid in G-I, relatively high and rapid in G-III, and low and slow in G-II. Accordingly, the voluminous ingestion of drug suspension can facilitate the gastric emptying, in turn may make the oral absorption of the drug rapid-and-uniform. The 20 ml/kg volume of sulfa drug suspension may practically be recommended for the oral administration in pigs.

Administration, Oral↗
PubMed1998

Relative bioavailability of atovaquone suspension when administered with an enteral nutrition supplement.

OBJECTIVE: To compare the relative bioavailability of a single atovaquone 750 mg suspension oral dose when administered in the fasting state, after a normal breakfast, and after an enteral nutrition supplement. DESIGN: Ten healthy volunteers received a single dose of atovaquone suspension 750 mg/5 mL while fasting. At 2-week intervals, the subjects were then randomized in a crossover design to receive the atovaquone dose within 1 hour of consuming a normal breakfast (fat content 21 g) and 16 oz. of Sustacal Plus (fat content 28 g). Blood samples were collected at seven time points after each atovaquone dose. HPLC was used to determine the atovaquone concentrations in plasma. RESULTS: Administering atovaquone suspension with either a normal breakfast or an enteral nutrition supplement, such as Sustacal Plus, significantly increased the oral relative bioavailability. The mean AUC0-24 after the fasting dose was 43.4 micrograms.h/mL. The mean AUC0-24 values with breakfast (103.8 micrograms.h/mL) and Sustacal Plus (118.8 micrograms.h/mL) were significantly greater compared with fasting (p < 0.0001). CONCLUSIONS: This study has shown that the new atovaquone oral suspension also has significantly greater bioavailability when administered after food or a nutrition supplement that has a moderate fat content. Patients who require atovaquone therapy can use Sustacal Plus without risk of reduced absorption.

Administration, Oral↗
PubMedDate not supplied

On the structural features of fiber suspensions in converging channel flow.

The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in converging channel flow were calculated, and the evolutions of the fiber alignment and the bulk effective viscosity were analyzed. The results showed that the bulk stress and the effective viscosity were functions of the rate-of-strain tensor and the fiber orientation state; and that the fiber suspensions evolved to steady alignment and tended to concentrate to some preferred directions close to but not same as the directions of local streamlines. The bulk effective viscosity depended on the product of Reynolds number and time. The decrease of effective viscosity near the boundary benefited the increase of the rate of flow. Finally when the fiber alignment went into steady state, the structural features of fiber suspensions were not dependent on the Reynolds number but on the converging channel angle.

Computer Simulation↗
PubMed2006

Extemporaneous sildenafil citrate oral suspensions for the treatment of pulmonary hypertension in children.

PURPOSE: The stability of sildenafil citrate 2.5 mg/mL in two extemporaneously prepared oral suspensions stored at 4 and 25 degrees C was studied. METHODS: Thirty 25-mg tablets of sildenafil citrate were ground to powder, and the powder was combined with a 1:1 mixture of Ora-Sweet and Ora-Plus or a 1:1 mixture of methylcellulose 1% and Simple Syrup, NF, to produce two 2.5-mg/mL suspensions. Five plastic bottles of each suspension were stored in amber plastic prescription bottles at 4 or 25 degrees C. Samples were collected on days 0, 7, 14, 28, 42, 56, 70, and 91 for analysis of sildenafil content by high-performance liquid chromatography; pH was also measured. Samples were visually observed against black and white backgrounds. RESULTS: The mean concentration of sildenafil citrate exceeded 98% of the initial concentration in all samples at both temperatures throughout the 91-day study period. No changes in pH, odor, or physical appearance were observed. CONCLUSION: Sildenafil citrate 2.5 mg/mL in two extemporaneously compounded oral suspensions was stable for 91 days in plastic prescription bottles at 4 and 25 degrees C.

Child↗
PubMed1982

Barium sulfate suspensions: an evaluation of available products.

Commercially available barium sulfate suspensions were evaluated for suspension stability and coating characteristics important to the most commonly performed gastrointestinal examinations. Products tested included powders supplied in bulk, unit dose powders, and factory-prepared liquids. Results indicated considerable differences in suspension stability and coating properties among the products tested. Results also suggest that no single barium suspension currently available is likely to provide optimum performance during all of the more frequently performed studies.

Barium Sulfate↗
PubMed1998

Particle size determination of a flocculated suspension using a light-scattering particle size analyzer.

Microscopy is a useful and direct method for measuring the particle size of a suspension because, in addition to the particle size and size distribution, it provides visual detection of the shape and state of aggregation of the particles in the suspension. However, this method suffers from the shortcomings of being tedious and time consuming. In this study, a light-scattering particle size analyzer was used to determine the particle size and size distribution of a flocculated suspension. The sonication of the sample prior to and during measurement was found to be critical in ensuring that data are representative of the size distribution of the primary particles of the suspension. The light-scattering results were further confirmed by data generated using a polarized light microscope equipped with an image analyzer.

Benzocaine↗
PubMed1996

Comparison of a respiratory suspension aerosolized by an air-jet and an ultrasonic nebulizer.

In the absence of USP standards and performance monographs, this research sought to determine if differences in the aerosolization mechanism (air-jet vs. ultrasonic) affected droplet and insoluble particle deposition of a nebulized model respiratory suspension. Five milliliters of a model suspension containing 0.1% w/v fluorescein (to estimate droplet deposition) and known quantities of 1, 3, and 6 microns latex spheres (representing insoluble drug particles) was aerosolized from an air-jet and an ultrasonic nebulizer. Nebulized output was collected in a modified Andersen impactor. Samples were analyzed spectrophotometrically (490.5 nm) and by a Coulter Counter to estimate droplet and sphere deposition, respectively. The distribution of droplets throughout the modified impactor for both nebulizers suggested that both the air-jet and the ultrasonic nebulizer produced droplets (0.4 to 10 microns in aerodynamic diameter) large enough to incorporate 1, 3, and 6 microns insoluble spheres. However, Coulter Counter analysis of the sphere distribution revealed that while the air-jet nebulized output contained spheres of all sizes, this was not true for the ultrasonic nebulizer. In the ultrasonic nebulizer, 99% of the spheres (irrespective of size) were not aerosolized and were recovered from the nebulizer reservoir at the aerosolization end point. The results highlight the importance of evaluating performance of a respiratory suspension in combination with a specific nebulizer. When conducting in vitro inertial deposition testing of a respiratory suspension, it is inappropriate to assume that deposition trends of droplets will predict the deposition of the insoluble dispersed phase.

Aerosols↗
PubMed1982

Decreased viscosity of human erythrocyte suspension due to drug-induced spherostomatocytosis.

The effect of two cationic drugs (chlorpromazine and isoxsuprine) on the suspension viscosity of human erythrocytes were examined, comparing with the effect of anionic drugs. (1) As increasing the drug concentrations, the cationic drugs transformed the erythrocytes to stomatocytes, then to spherostomatocytes, while trinitrobenzene sulfonate, dehydroepiandrosterone sulfate and lysolecithin induced echinocytes, as well known. (2) The suspension viscosity decreased in parallel with the appearance of spherostomatocytes, but it increased in echinocytosis. (3) The membrane fluidity, measured by spin label method, was not a major determinant for the suspension viscosity in these cases, because of no systematic correlation. (4) The rheoscopic observation under shear force demonstrated that the spherostomatocytes deformed easily to ellipsoid with smooth cell surface, while the echinocytes less easily deformed to ellipsoid on which the small spikes persisted at higher shear. These distinct difference in deformed shape under high shear force could be related to the decreased suspension viscosity of spherostomatocytes. (5) In addition, the transformation to spherostomatocytes, thus the decreased viscosity, was primarily determined by the intramembraneous drug concentration.

Blood Viscosity↗
PubMed2000

Mathematical analysis of the effects of geometric parameters and mechanical properties of erythrocytes on the filterability of nonuniform suspensions.

Approaches to determination of the pattern of erythrocytes distribution with regard to the rates of their passage through pores (3 microm in diameter) of a membrane filter by processing the data on changes in the flow rates of erythrocyte suspensions with time (filtration curves) are discussed. We considered the case when the suspension consisted of two subpopulations of erythrocytes differing in a single parameter. Using a model describing the erythrocyte passage through a pore and a model describing filtration of a nonuniform suspension, we analyzed the dependences of filtration kinetics of such suspensions on the relative contents of the subpopulations and their rheological characteristics. It has been shown that the filtration rates of the major subpopulation and the minor abnormal subpopulation, and their relative contents can be determined from the analysis of filtration curves. This can be done when the filtration rate of cells from the minor subpopulation is at least one order of magnitude lower than the filtration rate of cells from the major subpopulation. Thus we can register the presence of the minor subpopulation in the range of 0.5-1%. If filtration rates are recorded at different osmolalities, their analysis makes it possible to determine the surface area, intracellular viscosity, and membrane rigidity of cells of the major subpopulation and, in certain cases, the same parameters for the cells of the minor subpopulation.

Erythrocyte Deformability↗
PubMed2001

[Extinction characteristics of TiO2 suspension for different band ultraviolet radiation].

This study focused on the global absorption characteristics of UVA, UVB and UVC radiation in the suspension of titanium-pollutant solution using 4-CBA-Na as a model pollutant. The result showed that the attenuation of ultraviolet in the suspensions conformed to Beer's Law, light intensity negative-exponentially attenuating with the optic path. The extinction coefficient increased with the titanium dosage by a quadratic polynomial law, which may be approximated by a linear function at lower dosage. The sum of the respective UVC or UVB extinction coefficient in pollutant solution and titanium-water suspension was found to approach the measured value in Titanium-Pollutant suspension. Larger extinction coefficient was observed for shorter UV wavelength, implying higher energy efficiency with UVC as ultraviolet source.

Catalysis↗
PubMedDate not supplied

[Production of stable Bacillus thuringiensis suspensions in an electromagnetic apparatus].

The experiment demonstrated the podibility of obtaining stable suspensions of B. subtilis, a microorganism used as an experimental model, in an electromagnetic apparatus with a bilateral inductor. The optimum conditions of obtaining such suspensions were chosen, these conditions excluding the inactivation of the bacteria used as a model in the course of the process. Suspensions containing 75% of culture fluid were shown to have the highest stability during prolonged storage. Suspensions on the basis of the crystal-forming bacteria B. thuringiensis sp. kurstaki, strain Z-52, used in the production of entomopathogenic preparations and characterized by high stability and good viability in the process of storage were prepared under the selected conditions. The apparatus used in these experiments was recommended for use in the technology of the production of biopreparations of the basis of the above-mentioned bacteria.

Bacillus thuringiensis↗
PubMed2001

Changes in vasoreactivity of rat pulmonary artery after 7 d tail-suspension.

OBJECTIVE: To clarify the effects of simulated microgravity on the local regulating function of the pulmonary circulation. METHOD: Rat tail-suspension (TS) was used as the animal model to simulate the effects of microgravity. The changes in responses of pulmonary artery to several vasoactive agents were determined by using in vitro vessel rings perfusion technique. RESULT: As for the endothelium-intact vessel rings from TS group compared with those from the control (C) group, the contractile responses of pulmonary artery to potassium chloride (KCl, 10 ~ 70 mmol/L) did not change obviously after 7 d tail-suspension, which were markedly diminished as to phenylephrine (PE, 10(-9) ~ 10(-5) mol/L). The vasodilatory responses to acetylcholine (ACh, 10(-9) ~ 10(-5) mol/L) were markedly enhanced, which did not change obviously as to captopril (Cap, 10(-5) ~ 3 x 10(-3) mol/L). The vasoreactivity of endothelium-removed pulmonary artery rings to all vasoactive agents did not change after 7 d tail-suspension as compared with those from control rats. CONCLUSION: The release of nitric oxide (NO) by rat pulmonary arterial endothelium was enhanced after 7 d tail-suspension. The vasodilatory function of pulmonary artery was enhanced.

Acetylcholine↗
PubMed1999

[Alterations of arterial vasoconstrictor responsiveness in rats during and after tail-suspension].

Objective. To characterize the time course of alterations in vasoconstrictor properties of arteries during simulated weightlessness, and to examine whether these alterations are reversible. Method. The tail-suspended rat model was used to simulate weightlessness, and the alterations in vasoconstrictor response were examined in vitro using isolated arterial rings. Result. Compared with that of controls, contractile tension evoked by KCl and phenylephrine (PE) were lower in abdominal aortic, mesenteric and femoral arterial rings from 2 wk tail-suspended rats (P<0.05); after 4 wk tail-suspension, the responses of mesenteric and femoral arterial rings to KCl or PE were further decreased (P<0.05); but contraction responses of arterial rings from 8 wk tail-suspended rats were similar to that of 4 wk simulated microgravity rats. The reversibility of altered arterial vasoreactivity after 4 wk tail-suspension was observed for 5 wk. Vasoreactivity of abdominal aortic rings was recovered after first week of recovery, but it took five weeks that altered vasoreactivity of mesenteric and femoral artery got back to normal. Conclusion. The alterations in constrictor properties of arteries are dependent on both the duration of tail-suspension and the position of artery, the diminished vasoconstrictor properties appear to reach a new steady state after 4 wk tail-suspension, and the changes are reversible.

Animals↗