Intratracheal recombinant human deoxyribonuclease in acute life-threatening asthma refractory to conventional treatment

Recombinant human deoxyribonuclease (rhDNase) is a mucolytic agent used to relieve peripheral airway obstruction in patients with cystic fibrosis. We report dramatic sustained improvement following the intratracheal administration of rhDNase to a 3-yr-old boy with acute life-threatening asthma in whom 48 h of aggressive therapy had failed.      

Blood propofol concentration and psychomotor effects on driving skills

We studied psychomotor performance in 10 healthy volunteersduring recovery after a target-controlled infusion of propofol.Choice reaction time, dual task tracking with secondary reactiontime and a within-list recognition task were assessed at targetblood propofol concentrations of 0.8, 0.4 and 0.2 µg ml^–1.Performance was impaired most at the highest blood propofolconcentration (choice reaction time increased by a mean of 247ms and secondary reaction time by a mean of 178 ms). Choicereaction time and dual task tracking with secondary reactiontime were the most sensitive and reliable methods of assessment(significant difference from baseline (P<0.05) at a propofolconcentration of 0.2 µg ml^–1 with choice and secondaryreaction time testing). Within-list recognition assessment ofmemory was not sufficiently sensitive at very low propofol concentrations.The impairment in choice and secondary reaction time with ablood propofol concentration of 0.2 µg ml^–1 wasless than that observed with a blood alcohol concentration of50 mg 100 ml^–1 and no greater than that observed witha blood alcohol concentration of 20 mg 100 ml^–1 in a previousstudy involving healthy volunteers. Br J Anaesth 2000; 85: 396–400 ^* Corresponding author     

Management of Parkinson Disease

Parkinson disease is a movement disorder caused by progressive dopaminergic neuron degeneration in the substantia nigra and characterized by four cardinal symptoms: resting tremor, bradykinesia, rigidity, and postural instability. Levodopa has been considered the first-choice intervention for Parkinson disease for more than three decades. However, up to 50–90% of levodopa-treated patients develop motor complications within 5–10 years of starting treatment. It is important, therefore, to delay the initiation and/or reduce the dosage requirements of levodopa. The non-ergoline dopamine agonist ropinirole (Requip®) is used as monotherapy or in combination with low-dose levodopa in patients with early disease, and as an adjunct to levodopa in patients with advanced Parkinson disease.As an adjunct to levodopa therapy in patients with more advanced disease, ropinirole is generally more effective than bromocriptine and more effective than placebo. Ropinirole (with or without levodopa) is more effective than placebo and at least as effective as bromocriptine when administered as therapy for early Parkinson disease. It reduces the risk of dyskinesia relative to levodopa and maintains long-term control of the underlying disease symptoms, factors that are associated with improved functional ability. Ropinirole reduced the loss of putamen dopamine storage capacity compared with levodopa in a functional imaging study. However, it was unclear whether this resulted from any neuroprotective activity of ropinirole; further research is required to identify any clinically important neuroprotective activity of dopamine agonists. Ropinirole has a tolerability profile generally similar to that of bromocriptine and levodopa when used as monotherapy. In common with all dopaminergic agents, ropinirole has been linked with sedation and unintended sleep episodes; however, these effects may also result from the underlying disease process in patients with Parkinson disease.Only limited data are available from pharmacoeconomic evaluations of ropinirole. Nevertheless, a cost-minimization analysis indicates that, from a societal viewpoint in Canada, ropinirole is cost saving relative to treatment with levodopa plus a dopa decarboxylase inhibitor in patients with early Parkinson disease. Further economic and quality-of-life assessments of ropinirole are required, particularly comparisons with other dopamine agonists and antiparkinsonian interventions.In conclusion, ropinirole is established as an adjunct to levodopa in advanced Parkinson disease, and as monotherapy or in combination with low-dose levodopa in early disease. It is in the setting of early Parkinson disease that ropinirole may see greatest expansion of its overall role in disease management programs.     

Human myeloid alpha 3-fucosyltransferase is involved in the expression of the sialyl-Lewis(x) determinant, a ligand for E- and P-selectin

The sialyl-Lex determinant (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha- 1-->3]GlcNAc) has been identified as a major ligand in the selectin- mediated adhesion of neutrophils and monocytes to activated endothelium or platelets. This carbohydrate epitope is formed by the sequential action of alpha 3-sialyltransferase and alpha 3-fucosyltransferase on N- acetyllactosamine (Gal beta 1-->4GlcNAc) disaccharide termini of glycoconjugates. We have addressed the role of the human myeloid alpha 3-fucosyltransferase in the expression of this epitope at the leucocyte surface by determining its activity in human-mouse leukemic cell hybrids (WEGLI), normal human granulocytes and chronic myeloid leukemia (CML) cells using sialylated and desialylated glycoproteins and oligosaccharides as acceptor substrates. In contrast to what has been reported for the myeloid-type enzyme, we found that the alpha 3- fucosyltransferase of the cells studied can use sialylated acceptors be it that the activity is several times lower than with asialo- substrates. Characterization of the product obtained with a sialylated oligosaccharide indicated that the enzyme can catalyze the formation of the sialyl-Le(x) structure. Flow cytometry of the WEGLI cells using a sialyl-Le(x)-specific monoclonal antibody (MoAb) showed that these cells indeed express sialyl-Lex at their surface, provided that they contain human chromosome 11. Earlier the presence of this chromosome had been correlated with the expression of alpha 3-fucosyltransferase activity. In addition to sialyl-Le(x), WEGLI cells containing chromosome 11 showed high-expression levels of related structures recognized by antibodies VIM-2 and VIM-8, suggesting that fucose addition can occur at both distal and proximal GlcNAc residues in poly- N-acetyl-lactosaminoglycan sequences. Based on the human chromosome contents it could be ruled out that the alpha 3-fucosyltransferase of WEGLI cells is a Lewis-type alpha 3/4- or plasma-type alpha 3- fucosyltransferase, the genes of which have been mapped to chromosome 19. It is concluded that the enzyme studied is of the myeloid-type and indeed is involved in the synthesis of sialyl-Le(x) (and also VIM-2 and VIM-8 structures) in leukocytes provided that its expression is at a sufficiently high level.