A bioseparation apparatus with high-pressure fluid injection and fluid sampling.

A novel apparatus in which fluids may be injected and sampled at high pressure is described. Bioseparation applications of the apparatus were demonstrated in three model systems: (1) lambdaDNA was eluted under pressure from an anion exchange column into a low-salt (0.25 M) buffer, thereby eliminating conventional time-consuming desalting procedures required for downstream analysis of the DNA; (2) RNA was separated under pressure from a RNA/DNA mixture, thereby enabling rapid differential preparation of nucleic acids; and (3) an antibody was purified from a protein mixture by affinity capture at one pressure and dissociation from the antigen binding partner at a second pressure, thereby enabling the immunoreactivities of both antibody and antigen to be preserved during the separation process.

Chronic administration of levosulpiride and glycemic control in IDDM patients with gastroparesis.

Objective: We evaluated the effect of chronic administration of levosulpiride, a prokinetic drug that is a selective antagonist for D2 dopamine receptors, on the glycemic control of IDDM subjects.

Research Design And Methods: The study was performed on 40 long-standing IDDM subjects with clinical signs of autonomic neuropathy and delayed gastric emptying. Gastric emptying time and glycemic parameters (diurnal glycemic profile and HbA1c) were checked under double-blind conditions before and after the administration of levosulpiride at the dosage of 25 mg t.

Influence of culture conditions on monoamine oxidase A and B activity in rat astrocytes.

Astroglial cells dispersed from newborn rat hemispheres were established in medium supplemented with 20 per cent fetal calf serum (FBS) and then grown to a confluent monolayer in the presence of 10 per cent FBS or charcoal-stripped FBS (CS). Type 1 astrocytes were subcultured and either maintained under the same conditions of the primary cultures or converted to serum-free chemically defined medium (CDM). No differences were found in either MAO A or MAO B activity of astrocytes grown in the presence of FBS or CS after 15 and 21 days in vitro (day 1 and 6 of subculture).

Gastrokinetic effects of levosulpiride in dyspeptic patients with diabetic gastroparesis.

Objective: Antidopaminergic drugs may be useful in diabetic gastroparesis because the inhibitory activity of hyperglycemia on gastric motility seems to be related to dopamine receptor stimulation. For this reason, we evaluated the effect of levosulpiride on gastric emptying, dyspeptic symptoms, and metabolic parameters of insulin-treated diabetic patients.

Methods: Under double-blind conditions, 40 longstanding, insulin-treated dyspeptic patients with autonomic neuropathy and delayed gastric emptying were randomly submitted, with an interval of 15 days, to 4 wk of administration of both levosulpiride 25 mg t.

In vitro effects on monoamine uptake and release by the reversible monoamine oxidase-B inhibitors lazabemide and N-(2-aminoethyl)-p-chlorobenzamide: a comparison with L-deprenyl.

To investigate whether the reversible monoamine oxidase-B (MAO-B) inhibitors lazabemide and Ro 16-6491 have any additional effect on monoamine uptake and release, in vitro experiments were performed on rat forebrain synaptosomes and blood platelets. The effects of the two drugs were compared with those of L-deprenyl, the well-known irreversible MAO-B inhibitor which is reported to affect amine uptake. Both lazabemide and Ro 16-6491 behaved as weak inhibitors of [3H]monoamine uptake by synaptosomes, with a similar rank order of potency for amine uptake inhibition (noradrenaline (NA) > or = 5-hydroxytryptamine (5 HT) > dopamine (DA)).