Schistosoma mansoni cathepsin D1: Biochemical and biophysical characterization of the recombinant enzyme expressed in HEK293T cells.

Schistosomes express a variety of aspartyl proteases (APs) with distinct roles in the helminth pathophysiology, among which degradation of host haemoglobin is key, since it is the main amino acid source for these parasites. A cathepsin D-like AP from Schistosoma mansoni (SmCD1) has been used as a model enzyme for vaccine and drug development studies in schistosomes and yet a reliable expression system for readily producing the recombinant enzyme in high yield has not been reported. To contribute to further advancing the knowledge about this valuable antischistosomal target, we developed a transient expression system in HEK 293T mammalian cells and performed a biochemical and biophysical characterization of the recombinant enzyme (rSmCD1). It was possible to express a recombinant C-terminal truncated form of SmCD1 (rSmCD1ΔCT) and purify it with high yield (16 mg/L) from the culture supernatant. When analysed by Size-Exclusion Chromatography and multi-angle laser light scattering, rSmCD1ΔCT behaved as a dimer at neutral pH, which is unusual for cathepsins D, turning into a monomer after acidification of the medium. Through analytical ultrancentrifugation, the dimer was confirmed for free rSmCD1ΔCT in solution as well as stabilization of the monomer during interaction with pepstatin. The mammalian cell expression system used here was able to produce rSmCD1ΔCT with high yields allowing for the first time the characterization of important kinetic parameters as well as initial description of its biophysical properties.

Using a computer-based clinical management system to improve effectiveness of a homeopathicservice in a fundholding general practice

Problems which the development attempts to address. This study's overall objectives were to determine whether: the aims of collaboration between General Practitioner (GPs) and a homeopath... (AU)

A comparative study of a progestin-only oral contraceptive versus non-hormonal methods in lactating women in Buenos Aires, Argentina.

A non-randomized comparative clinical trial of the progestin-only oral contraceptive (POC), Ovrette (75 mcg norgestrel) (Wyeth), versus non-hormonal methods was conducted at two clinics in Buenos Aires, Argentina. The trial was designed to assess the breast-feeding patterns of women choosing progestin-only oral contraception and non-hormonal methods of contraception, and to study the relationship between lactation and the clinical performance of a POC. Five-hundred women were allocated to either the progestin-only pill group (n = 250) or to the non-hormonal group (n = 250) and were followed up monthly for six months after admission. Measurements in mean infant weight, mean infant length, and mean head circumference were similar throughout the follow-up period. Non-hormonal users reported significantly more self-perceived decreases in milk production at the 5th and 6th month follow-up intervals. Acceptance and continued use of the pill were excellent, with only one woman discontinuing because of a pregnancy which was attributed to user failure. The principal side effect reported by women in both groups was intermenstrual bleeding.

PIP: A nonrandomized, comparative, clinical trial of the progestin only oral contraceptive (OC) Ovrette (75 mcg norgestrel) vs. nonhormonal methods was conducted at 2 clinics in Buenos Aires, Argentina. The trial was designed to assess breast-feeding patterns of women choosing progestin- only OCs and nonhormonal methods of contraception and to study the relationship between lactation and the clinical performance of the OC. 500 women were allocated to either the progestin-only pill group (n=250) or t o the nonhormonal group (n=250) and were followed monthly for 6 months after admission. Measurements in mean infant weight, mean infant length, and mean head circumference were similar throughout the follow- up period. Nonhormonal users reported significantly more self-perceived decreases in milk production at the 5th an 6th month follow-up intervals. Acceptance and continued use of the pill were excellent, with only 1 women discontinuing because of a pregnancy which was the result of user failure. The principal side effect reported by women in both groups was intermenstrual bleeding.

Minimizing the risk of brain herniation during treatment of diabetic ketoacidemia: a retrospective and prospective study.

We studied retrospectively, 219 episodes of diabetic ketoacidemia in 119 patients aged 13 months to 30 years, to determine the trend of the concentration of sodium in serum as glucose declined during treatment of uncomplicated episodes and of episodes with complications attributable to brain swelling. Of 20 complication, 13 were minor (headache only) and 7 major (death or near death). The concentration of sodium in serum failed to rise as that of glucose declined in 82 (54%) of 164 uncomplicated episodes and in 18 (95%) of 20 complicated episodes (p less than 0.01). Hence complications were more likely to occur among patients with a failure of the concentration of sodium to rise as glucose declined. Fifty-eight episodes of diabetic ketoacidemia in 40 patients aged 1 1/2 to 20 years were then studied prospectively on a 48-hour treatment plan to provide the volume of deficit evenly, with half the deficit of sodium in the first 42 hours. Sodium concentration in serum rose in 55 (95%) of 58 episodes as that of glucose declined. No patient had a major complication. We conclude that failure of the sodium concentration measured in serum to rise as glucose concentration declines is a marker for excessive administration of free water. An expanded repair period, with repair fluid containing an average of 125 mmol/L Na+ early in therapy, will usually protect against a downward trend in the concentration of sodium in serum and therefore against a rapid decline in effective serum osmolality. This regimen may be protective against near-death episodes and brain herniation during treatment.

(-)-delta-N-normethylskytanthine from Tecoma arequipensis.

Bark of Tecoma arequipensis yielded the major alkaloidal component (-)-delta-N-normethylskytanthine whose structure was proven by X-ray diffraction analysis of the N-thiourea derivative. The stereochemistry of 1 at all four centers was enantiomeric with that of skytanthine previously reported from Tecoma stans and Skytanthus acutus. Gc-ms of the crude base fraction indicated the presence of several related alkaloids as very minor constituents.

Tracheal bronchus: association with respiratory morbidity in childhood.

An aberrant right upper lobe (RUL) bronchus arising from the trachea (tracheal bronchus) can be responsible for recurrent pneumonia. In this hospital, 2% of children requiring bronchoscopy for respiratory symptoms are found to have a tracheal bronchus, which is frequently thought to be an incidental finding. We reviewed findings in 18 patients to determine when a tracheal bronchus is of clinical significance. The age at presentation ranged from 1 day to 54 months (mean 17 months). The children had recurrent pneumonia (nine), stridor (six), respiratory distress (two) and a thoracic mass (one). Other congenital abnormalities were present in 14, including Down syndrome (two), tracheoesophageal fistula (two), and fused or hypoplastic first and second ribs (four). Recurrent RUL pneumonia was present in five. Bronchiectasis or bronchial stenosis was shown by bronchography in four of five; in all five the right upper lobe was surgically resected, with resolution of the recurrent pneumonias. The presence of a clinically significant tracheal bronchus should be considered in every child with recurrent RUL pneumonia, especially in children with Down syndrome or rib abnormalities; if bronchiectasis or bronchial stenosis is found, surgical resection should be performed.