Effects of iontophoretic administration of acetylcholine to rabbit motor cortex neurons on the functioning of intracortical connections

The rat D2(long) dopamine receptor has been expressed in the fission yeast Schizosaccharomyces pombe at levels of about 1 pmol/mg of protein. The recombinant receptor, analysed in ligand binding experiments, exhibits properties typical of a D2 dopamine receptor and the affinities of antagonists agree with values obtained for the receptor expressed in mammalian systems although the affinities of some antagonists are lower. Substituted benzamide antagonists show lower affinities in the absence of sodium ions whereas clozapine and classical antagonists mostly show higher affinities. Agonist binding is insensitive to the effects of GTP indicating lack of a stable interaction with G-proteins.     

Occupational bronchial asthma

Examination of 400 patients with occupational bronchial asthma helped to identify various clinical and pathogenetic variants of the disease in accordance with independent and combined occupational allergens and irritants. The authors evaluated diagnostic value of endonasal tests with occupational allergen, rhinocytologic tests and some specific allergologic blood tests in vitro.     

Central motor conduction in motor neuron disease

Central motor conduction time (CMCT) to abductor digiti minimi (ADM) and tibialis anterior (TA) was measured in 21 patients of motor neuron disease (MND). In the upper limb, the motor pathways were inexcitable in 13 and central motor conduction time (CMCT-ADM) was prolonged in 7 sides. In the lower limbs the motor pathways were inexcitable in 10 and CMCT-TA was prolonged in 14 sides. The CMCT abnormalities did not follow a constant pattern but were randomly distributed and were asymmetric in the upper limbs in 7 and lower limbs in 3 patients. Asymmetric and randomly focal abnormalities in central motor conduction in our patients are consistent with asymmetric and focal neuronopathy in MND.     

N-glycosylation of recombinant human interferon-gamma produced in different animal expression systems

Recombinant human interferon-gamma (IFN-gamma) was expressed in Chinese hamster ovary cells, baculovirus-infected Sf9 insect cells and the mammary gland of transgenic mice. The N-linked carbohydrate populations associated with both Asn25 and Asn97 glycosylation sites were characterized by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) in combination with exoglycosidase array sequencing. A site-specific analysis of dual (2N) and single (1N) site-occupancy variants of IFN-gamma derived from Chinese hamster ovary cells showed that N-glycans were predominantly of the complex bi- and triantennary type. Although Asn25-linked glycans were substituted with a core fucose residue, Asn97 N-glycans were predominantly non-fucosylated, and truncated complex and high-mannose oligosaccharide chains were also evident. Transgenic mouse derived IFN-gamma exhibited considerable site-specific variation in N-glycan structures. Asn25-linked carbohydrates were of the complex, core fucosylated type, Asn97-linked carbohydrates were mainly of the oligomannose type, with smaller proportions of hybrid and complex N-glycans. Carbohydrates associated with both glycosylation sites of IFN-gamma from Sf9 insect cells were mainly tri-mannosyl core structures, with fucosylation confined to the Asn25 site. These data demonstrate the profound influence of host cell type and protein structure on the N-glycosylation of recombinant proteins.