Synergistic effect of pendant hydroxypropyl and pyrrolidine moieties randomly distributed along polymethacrylamide backbones on in vitro DNA-transfection.

In this work, the cationic monomer N-ethyl pyrrolidine methacrylamide (EPA) was copolymerized with the neutral monomer N-hydroxypropyl methacrylamide (HPMA) at different molar ratios obtaining linear random copolymers that were characterized and evaluated in vitro as non-viral gene carriers using murine Swiss 3T3 fibroblasts. The copolymers with excess or equimolar amount of EPA were able to complex DNA forming stable polyplexes with an average size between 50 and 200 nm, while the copolymers with an excess of HPMA do not. Cell viability was shown to depend on the EPA/HPMA molar ratio, exhibiting the equimolar copolymer poly (EPA-co-HPMA) 50:50 (EPA50) a full cytocompatibility, similar to the HPMA-rich systems. This copolymer EPA50 has also shown significantly higher transfection levels than the systems with other compositions and the positive controls poly L-lysine (PLL) and poly EPA (pEPA). This statistical equimolar copolymer EPA50 has unique properties related to its composition and microstructure, which allows it to complex DNA, showing an excellent biocompatibility and high transfection efficiency.

pH-sensitive polymer hydrogels derived from morpholine to prevent the crystallization of ibuprofen.

Various pharmaceutical formulations of ibuprofen are available including oral tablets, suspensions, suppositories and transdermal gels and creams. Aqueous ibuprofen solubility is dependent on pH increasing solubility when increasing pH. The very low aqueous solubility of ibuprofen can lead to a segregation of the drug in to microdomains and possible crystallization which will affect the release profile even leading to possible damage of the mucous membrane of the stomach. Therefore, homopolymers and copolymers of N-ethylmorpholine methacrylamide (EMA) and N, N-dimethylacrylamide (DMA) hydrogels have been prepared to be applied as matrices for ibuprofen release as a method for minimizing these issues. The hydrogels were loaded with ibuprofen and the release over time was tested at 37°C and at different pH values: 2, 5 and 7.4. Fourier-transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) was performed in order to identify the stretching vibrations of the carbonyl group for each component. Dissolution of the ibuprofen from the formulations at different pHs was studied using the ATR-FTIR spectroscopic imaging. The results showed that for DMA hydrogels, most of ibuprofen was released as non crystalline ibuprofen at pH 7.4 but it was not able to prevent crystallization at pH 2 and 5. In contrast, the EMA hydrogels were able to prevent crystallization of the ibuprofen at all pHs. Finally, it was demonstrated that there is a minimum concentration at which the polymer becomes ineffective.

[Effects on the newborn infant of thiopental and propofol used in anesthetic induction in cesarean section]. / Efectos sobre el neonato del tiopental o propofol utilizados en la inducción anestésica de la intervención cesárea.

OBJECTIVES: To compare the effects of an anesthetic induction dose of thiopental to that of propofol on the vitality of the neonate, as measured by Apgar score and the interval between extraction of the newborn and unassisted respiration. PATIENTS AND METHODS: One hundred ASA I-II women undergoing cesarean section were randomly assigned to two groups of 50. Anesthesia was induced with thiopental 4 mg/kg in one group; in the other group, propofol 2 mg/kg was used. Time intervals recorded were induction-to-extraction, uterine incision-to-extraction and extraction-to-unassisted respiration. An Apgar score was recorded 1, 5 and 10 min after birth. For statistical analysis, each group was divided into three subgroups, in accordance with the reason for performing the cesarean section: subgroup 1, elective cesarean; subgroup 2, emergency cesarean due to dystocia or failure; subgroup 3, emergency cesarean section due to acute fetal distress. RESULTS: Means of intervals for induction-extraction and uterine incision-extraction showed no significant differences. All induction-extraction intervals were under 10 min (4.94 +/- 1.55 min) and all uterine incision-extraction intervals were under 180 sec, with most staying under 90 sec (43.13 +/- 25.76 sec). No statistically significant differences were found for vitality between the two groups of neonates. CONCLUSIONS: If the induction-extraction interval is 10 min or less, both thiopental (4 mg/kg) and propofol (2 mg/kg) given in a single dose for induction of general anesthesia in all types of cesarean section are equally safe for the newborn infant.

Giant meningioma in a 5-month-old infant.

A case of intracranial meningioma is reported in a 5-month-old infant. To date, 25 cases have been reported in the world literature in children less than 1 year of age. Macrocephaly was the most prominent clinical finding. Skull radiological studies, head CT scans, and cerebral angiography were definitive tools in making the diagnosis. Pathological analysis was conclusive. Complete surgical extirpation was the treatment of choice; the tumor weighed 600 g. The child remains stable 24 months later.