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Biomedical subjects

A Sallam

Publications and source records attributed to A Sallam.

7 recordsLinked to original sources
PubMed2004

Lactic acid-induced modifications in films of Eudragit RL and RS aqueous dispersions.

Eudragit RL (ERL) and RS (ERS) are polymethacrylate co-polymers, used in film coating of sustained release dosage forms, possessing some hydrophilic properties due to the presence of quaternary ammonium groups (QAG), where ERL contains more of such groups, hence more permeable, than ERS. However, because these groups ionize in solution, they undergo electrostatic interaction with negatively charged species. This phenomenon was utilized in this study to introduce modification in the film properties of ERL and ERS by interaction with lactic acid (LA). Thermal and mechanical analyses were carried out on polymeric free films. DSC showed a shift in Tg of the film while 1H NMR spectroscopy revealed a significant deshielding in the peak of QAGs protons after interaction with LA. Stress-strain test showed an increase in three mechanical parameters of the new film (containing LA): tensile strength to modulus ratio, relative surface energy and toughness index, indicating an enhancement in the mechanical stress resistance. Tablets coated with LA-containing films showed an increase in the release rate and extent and good stability upon aging, compared to those coated with the original film.

Acetaminophen↗
PubMed2001

The use of a modified hypo-osmotic swelling test for the selection of viable ejaculated and testicular immotile spermatozoa in ICSI.

A modified hypo-osmotic solution was used to select viable ejaculated and testicular spermatozoa to perform intracytoplasmic sperm injection (ICSI) in 27 treatment cycles from patients with total absence of sperm motility. The treatment cycles consisted of 15 cycles in which ejaculated spermatozoa were used and 12 cycles in which testicular spermatozoa were used. The hypo-osmotic solution consisted of 50% culture medium and 50% deionized water and was shown in previous in-vitro studies to be superior to the original solution used in the classical hypo-osmotic swelling test. Fertilization was achieved in 37.3% of the oocytes injected. Embryos were replaced in 70.4% of the cycles with a mean of 2.0 embryos per cycle. There were no statistically significant differences between the ejaculated sperm group and the testicular sperm group in the fertilization rate (42.7 versus 30.1%) or in the cleavage rate (92.7 versus 77.3%). Four pregnancies resulted, two in the ejaculated sperm group and two in the testicular sperm group, a pregnancy rate of 14.8%. All pregnancies were singletons but one pregnancy in each group had an early miscarriage. There were no statistically significant differences between both groups in the pregnancy rates (13.3 versus 16.7%), in the implantation rates (5.3 versus 11.8%) or in the delivery/ongoing pregnancy rates (6.7 versus 8.3%). It is concluded that the use of this solution to select viable but immotile spermatozoa for ICSI is a simple and practical method and is associated with acceptable fertilization and pregnancy rates.

Adult↗
PubMed2000

Aqueous solubility of diclofenac diethylamine in the presence of pharmaceutical additives: a comparative study with diclofenac sodium.

Aqueous solubility of diclofenac diethylamine (DDEA), a nonsteroidal anti-inflammatory drug currently formulated as a topical emulgel, was studied in the presence of pharmaceutical additives and compared with diclofenac sodium (DS). Electrolytes at low concentrations exhibited a salting-in effect on DDEA with peak solubility that was attributed to the association of DDEA into micelles, followed by a salting-out effect at higher concentrations, by which structure formation by DDEA molecules increased and precipitation occurred. For DS, which is not capable of forming micelles, the salting-out effect was dominant due to the common ion effect. Cosolvents displayed significant enhancement in solubility of both salts except glycerol, which showed a slight increase in solubility of DDEA and a decrease in solubility of DS due to transformation into the less soluble hydrate form. Ethanol and polyethylene glycol (PEG) 400 cosolvent systems at all concentrations showed positive deviations from the log-linear solubility equation. In the case of propylene glycol (PG) cosolvent systems, negative deviations were observed at low volume fractions of cosolvent, while positive deviations were observed at high volume fractions of cosolvent for DS and DDEA. The parent drug, being less ionizable and highly nonpolar, showed negative deviations up to 90% PG content. Thus, the positive deviations for DS and DDEA could be attributed to the more ionizable carboxylic group and its higher ability for hydrogen bonding at higher fractions of cosolvent. Polyvinylpyrrolidone (PVP) and PEG4000 or PEG6000 enhanced the solubility of DS and DDEA, with PVP exerting higher solubilizing efficiency and DS showing better solubility than DDEA. Solubilities of DS in Tween 80 (T80) and Pluronic F-127 (PF127) aqueous solutions were almost similar, while the solubility of DDEA in the presence of T80 was higher than the solubility in the presence of PF127. DS appeared to be located more in the polyoxyethylene mantle of the micelles, while DDEA was located more in the core of the micelles.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Reference values for the midluteal plasma progesterone concentration: evidence from human menopausal gonadotropin-stimulated pregnancy cycles.

OBJECTIVE: To determine reference values for the midluteal plasma progesterone concentration. DESIGN: Retrospective analysis. SETTING: Infertility clinic at an academic medical center. PATIENT(S): One hundred ninety-two infertile women who became pregnant after induction of ovulation with hMG. INTERVENTION(S): The plasma progesterone level was measured during the midluteal phase of the hMG treatment cycle. MAIN OUTCOME MEASURE(S): The midluteal plasma progesterone concentration was correlated with the outcome of the pregnancy. RESULT(S): In this cohort of 192 women in whom ovulation was induced with hMG and 5,000 IU of hCG, the mean midluteal plasma progesterone concentrations were 29.07 ng/mL, 25.85 ng/mL, 31.49 ng/mL, 41.39 ng/mL, and 28.64 ng/mL in all cycles that resulted in pregnancy, cycles that resulted in full-term singleton pregnancy, cycles that resulted in full-term multiple pregnancy, cycles that resulted in preterm pregnancy, and cycles that ended in miscarriage, respectively. There was no statistically significant difference in the progesterone concentration between the cycles that resulted in full-term pregnancy and those that ended in miscarriage, but there was a statistically significant difference between the cycles that resulted in singleton pregnancy and those that resulted in multiple pregnancy. The minimum value that was compatible with a full-term pregnancy in this cohort of women was 10.83 ng/mL. CONCLUSION(S): In a cohort of 192 women, the minimum plasma progesterone concentration on day 7 in women who attained a full-term pregnancy after induction of ovulation with 5,000 IU of hCG was 10.83 ng/mL.

Abortion, Spontaneous↗
PubMed1999

Mathematical relationships between uterine contractions, cervical dilatation, descent and rotation in spontaneous vertex deliveries.

OBJECTIVE: To determine the mathematical relationships between the strength and duration of the uterine contractions, the descent and rotation of the fetal head and the degree of cervical dilatation in 50 multiparous women with spontaneous vaginal deliveries using a simple device applied to the fetal vertex. METHOD: A simple device for monitoring the progress of labor was applied to the fetal vertex. The device allows the continuous monitoring of descent and rotation of the fetal head. The amount of descent and the degree of rotation were also determined by repeated vaginal examinations as well as the degree of cervical dilatation. The frequency of uterine contractions was also recorded on a partogram. RESULT: A good correlation was found between the amount of descent of the fetal vertex (r = 0.975) and between the degree of rotation of the fetal head (0.83) determined by both methods. Multiple regression analysis was then performed and the degree of cervical dilatation in cm at any given time during the first stage of labor was found to be equal to 2.859 + 0.583 fetal head station in (cm) + 0.1983 internal rotation in degrees -0.0493 (station x internal rotation) + 0.1599 station2 + 0.3622 uterine contractions per 10 min. A nomogram was constructed allowing the calculation of cervical dilatation for a given station of the head, degree of rotation and frequency of uterine contractions. CONCLUSION: There is a defined mathematical relationship between the degree of descent and rotation of the fetal head, the degree of cervical dilatation and the frequency of uterine contractions in multiparous women with vertex presentation. The first three variables can be continuously determined by using the described device. Incorporation of the device into a reusable fetal scalp electrode allows the dual mechanical and electronic monitoring during labor with minimal vaginal examinations.

Cervix Uteri↗
PubMed1999

Interaction of two diclofenac acid salts with copolymers of ammoniomethacrylate: effect of additives and release profiles.

The copolymer of ammoniomethacrylate Eudragit RL (ERL) interacted with diclofenac acid salts (sodium and diethylamine salts) in aqueous solutions, forming a complex. Sorption experiments were done in aqueous solutions of either sodium lauryl sulfate (SLS), Tween 20, or Tween 80. The SLS competed strongly with the drug, even at low concentrations, and reduced significantly the amount of drug sorbed by ERL. Tweens at high concentrations exhibited two phase profiles: the sorption phase, which was short and during which drug concentration dropped sharply, and the release phase, during which the drug was released slowly over 24 hr and which was accompanied by dispersion of ERL particles into the colloidal dispersion. The interaction was dependent on temperature, ionic strength, and nature of the additives. The extent of interaction in water and phosphate buffer solutions was in the following order: water > pH 6 > pH 7-8. In-vitro dissolution studies of the dried complex were done over 24 hr. In water, the drug remained bound to the polymer. In aqueous surfactant solutions (SLS, Tween 20, and Tween 80) and phosphate buffer at pH 6.8, a linear relationship between drug concentration and the square root of time was obtained, indicating a matrix diffusion-controlled mechanism. However, 100% release was not reached, and resorption was observed in the phosphate buffer solution.

Adsorption↗