Showing papers by "University of Hertfordshire published in 1992"

Protein-DNA interactions at a yeast replication origin.

Abstract: An understanding of the protein-DNA interactions in vivo at origins of DNA replication in eukaryotes is essential to delineate the mechanism of initiation of DNA synthesis and its control in the cell cycle. In the yeast Saccharomyces cerevisiae, a family of sequences known as autonomously replicating sequences (ARSs) function as origins of bidirectional DNA replication on plasmids and, in several instances, also in their normal chromosomal location. Here we use nucleotide resolution genomic footprinting to investigate the association of proteins with ARS1. Nuclease protection patterns indicate that at least two different cellular factors interact with functional elements in ARS1. The first seems to be ARS-binding factor 1. The second seems to be a novel protein that generates extensive protection over the essential ARS consensus sequence and phased DNaseI-sensitive sites across a functionally important flanking sequence. Hypersensitivity of this region to cleavage by copper phenanthroline indicates that it is under torsional strain, analogous to that produced at transcriptional start sites by assembly of an initiation complex. The protection in situ is similar to that generated by the origin recognition complex (ORC) protein.

Personal computer with broadcast receiver on expansion board controlled by computer microprocessor

Abstract: A broadcast receiver (22) for receiving television broadcast signals carrying encoded data e.g. teletext information, includes a tuner (30), a demodulator (32) and a data extractor (36) for decoding the data. The receiver is coupled to a computer through a bus (38) and an interface controller (40). The tuner (30), the demodulator (32) and the data extractor (36) are each individually controllable by the interface controller (40) in response to instructions from the computer to vary any of the tuning, the demodulation parameters, or the data extraction parameters. A data processor (54) processes the extracted data, and can also control the tuner (30), the demodulator (32) and the data extractor (36).

Color image processing

Abstract: Apparatus for performing a color transformation or color retouch operation on multibit digital data defining P color components of image pixels. The apparatus comprises a look-up table (2) which is addressed by N most significant bits (MSBS) of each color component value and which contains coarse versions of output pixel color component values. An interpolator (3) is responsive to M least significant bits (LSBS) of each color component value to interpolate fine versions of the output pixel values from the coarse output pixel values obtained from the look-up table. A processor loads coarse output pixel data for each color component into the 2NP addresses of the look-up table which may be addressed by the M MSBs of the input pixel data. The processor (8) is adapted to cause the value of N progressively to increase with successive iterations.

Regulation of Photosynthetic Rate of Two Sunflower Hybrids under Water Stress

Abstract: The effect of short-term water stress on photosynthesis of two sunflower hybrids (Helianthus annuus L. cv Sungro-380 and cv SH-3622), differing in productivity under field conditions, was measured. The rate of CO2 assimilation of young, mature leaves of SH-3622 under well-watered conditions was approximately 30% greater than that of Sungro-380 in bright light and elevated CO2; the carboxylation efficiency was also larger. Growth at large photon flux increased assimilation rates of both hybrids. The changes in leaf composition, including cell numbers and sizes, chlorophyll content, and amounts of total soluble and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) protein, and in Rubisco activity and amount of ribulose-1,5-bisphosphate (RuBP) were determined to assess the factors regulating the differences in assimilation of the hybrids at high and low water potentials. The amounts of chlorophyll, soluble protein, Rubisco protein and the initial activity of Rubisco and its activation state did not differ significantly between hybrids. However, unstressed leaves of SH-3622 had more, smaller cells per unit area and 60% more RuBP per unit leaf area than that of Sungro-380. Water stress developing over 4 days decreased the assimilation of both hybrids similarly. Changes in the amounts of chlorophyll, soluble and Rubisco protein, and Rubisco activity and activation state were small and were not sufficient to explain the decrease in photosynthesis; neither was decreased stomatal conductance (or stomatal “patchiness”). Reduction of photosynthesis per unit leaf area from 25 to 5 micromoles CO2 per square meter per second in both hybrids was caused by a decrease in the amount of RuBP from approximately 130 to 40 micromoles per square meter in SH-3622 and from 80 to 40 micromoles per square meter in Sungro. Differences between hybrids and their response to water stress is discussed in relation to control of RuBP regeneration.

Fluid droplets production apparatus and method

Abstract: A fluid droplet production apparatus, for example, for use an atomizer spraying device, has a membrane which is vibrated by an actuator, which has a composite thin-walled structure and is arranged to operate in a bending mode. Fluid is supplied directly to a surface of the membrane, as fluid is sprayed therefrom on vibration of the membrane.

Dependence of photosynthesis of sunflower and maize leaves on phosphate supply, ribulose-1,5-bisphosphate carboxylase/oxygenase activity, and ribulose-1,5-bisphosphate pool size

Abstract: Sunflower (Helianthus annuus L. cv Asmer) and maize (Zea mays L. cv Eta) plants were grown under controlled environmental conditions with a nutrient solution containing 0, 0.5, or 10 millimolar inorganic phosphate. Phosphate-deficient leaves had lower photosynthetic rates at ambient and saturating CO2 and much smaller carboxylation efficiencies than those of plants grown with ample phosphate. In addition, phosphate-deficient leaves contained smaller quantities of total soluble proteins and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) per unit area, although the relative proportions of these components remained unchanged. The specific activity of Rubisco (estimated in the crude extracts of leaves) was significantly reduced by phosphate deficiency in sunflower but not in maize. Thus, there was a strong dependence of carboxylation efficiency and CO2-saturated photosynthetic rate on Rubisco activity only in sunflower. Phosphate deficiency decreased the 3-phosphoglycerate and ribulose-1,5-bisphosphate (RuBP) contents of the leaf in both species. The ratio of 3-phosphoglycerate to RuBP decreased in sunflower but increased in maize with phosphate deficiency. The calculated concentrations of RuBP and RuBP-binding sites in the chloroplast stroma decreased markedly with phosphate deficiency. The ratio of the stromal concentration of RuBP to that of RuBP-binding sites decreased in sunflower but was not affected in maize with phosphate deficiency. We suggest that a decrease in this ratio made the RuBP-binding sites more vulnerable to blockage or inactivation by tight-binding metabolites/inhibitors, causing a decrease in the initial specific activity of Rubisco in the crude extract from phosphate-deficient sunflower leaves. However, the decrease in Rubisco specific activity was much less than the decrease in the RuBP content in the leaf and its concentration in the stroma. A large ratio of RuBP to RuBP-binding sites may have maintained the Rubisco-specific activity in phosphate-deficient maize leaves. We conclude that the effect of phosphate deficiency is more on RuBP regeneration than on Rubisco activity in both sunflower and maize.

Impact of aircraft and surface emissions of nitrogen oxides on tropospheric ozone and global warming

Abstract: ACTUAL and potential increases in aircraft traffic are causing concern about the effects of aircraft exhaust emission on atmos-pheric chemistry. Model results1–3 and measurements4–6 in the Northern Hemisphere have shown that growth in surface emissions of nitrogen oxides and hydrocarbons leads to increases in concentration of tropospheric ozone. Tropospheric ozone is toxic to plants, humans and other organisms, and it is a greenhouse gas7–9. The radiative forcing of surface temperature is most sensitive to changes in tropospheric ozone at a height of ∼12 km (ref. 8), where aircraft emissions of nitrogen oxides are at a maximum and where the model sensitivity of ozone to nitrogen oxide emissions is enhanced. Our model results show that the radiative forcing of surface temperature is about thirty times more sensitive to aircraft emissions of nitrogen oxides than to surface emissions. We also find that the impact on global warming of increases in tropospheric ozone caused by increases in surface emissions of nitrogen oxides has previously been overestimated by a factor of five1,10, owing to an error in the calculation of the ozone budget.

Role of horizontal genetic exchange in the antigenic variation of the class 1 outer membrane protein of Neisseria meningitidis.

Abstract: Summary The nucleotide sequences of the genes encoding the class 1 outer membrane protein of Neisseria meningitidis (PorA) from 15 meningococcal isolates have been examined. These strains, isolated over a number of years, represented a variety of serological types, clonal groups, and geographical locations. Analysis of the aligned nucleotide sequences showed that the known serological relationships between these proteins were not necessarily reflected throughout the nucleotide sequences of their genes. The uneven distribution of base substitutions, revealed by a comparison of the informative bases, suggested that these genes possessed a mosaic structure. This structure probably resulted from the horizontal transfer of DNA between strains and would have contributed to both the generation and the spread of novel antigenic variants of the protein. In addition, the nucleotide differences between porA genes from different strains were not consistent with the nucleotide sequence divergence of the whole chromosome, as indicated by pulsed-field get electrophoresis (PFGE) fingerprinting techniques: some strains with divergent PFGE fingerprints shared porA genes with extensive regions of nucleotide sequence identity and, conversely, some strains with similar chromosome structures possessed porA genes with different nucleotide sequences and serological properties. This suggested that entire genes had been exchanged between strains. Given that the meningococcal class 1 OMP is a major component in novel vaccines, some of which are currently undergoing field trials, the potential of horizontal genetic exchange to generate antigenic diversity has implications for the design of such vaccines.

The role of cytochrome P4502D6 in the metabolism of paroxetine by human liver microsomes.

Abstract: Paroxetine is a selective serotonin reuptake inhibitor possessing anti-depressant activity. Demethylenation of the methylenedioxy phenyl group is the initial step in its metabolism, the liberated carbon appearing in vitro as formate. A radioassay involving [14C-methylenedioxy] paroxetine was developed and used to examine the role of cytochrome P4502D6 in paroxetine metabolism by human liver microsomes. The rate of formate production was much higher in microsomes from an extensive metaboliser of debrisoquine than from a poor metaboliser. Also, demethylenation of paroxetine was inhibited by the quinidine and quinine isomer pair in microsomes from the extensive metaboliser only. These observations strongly suggested that the process was catalysed by the enzyme cytochrome P4502D6. Metabolism could not be completely inhibited by quinidine, the residual activity representing the contribution of at least one other enzyme. The ability of microsomes from a poor metaboliser of debrisoquine to demethylenate paroxetine provided further evidence for the involvement of an enzyme distinct from P4502D6. This was confirmed by kinetic analysis of the process in microsomes from both poor and extensive metabolisers. It is concluded that, in man, the initial step of paroxetine metabolism is performed by at least two enzymes, one of which is cytochrome P4502D6.

An empirical model for predicting microhabitat of 0+ juvenile fishes in a lowland river catchment

Abstract: Species-habitat relationships are an important aspect of fish life history, particularly in early ontogeny. To address the lack of information on the microhabitat use/requirements of European coarse fishes, particularly 0-group fishes in riverine systems, an empirical model was generated from data collected in the River Great Ouse catchment (UK). During 7 weeks in autumn 1990, data on young-of-the-year (0+) juvenile fishes and 15 environmental variables were collected at 2800 stratified, random point samples within 130 study sites (streams, rivers, side-channels, backwaters). Of 24 species of 0+ fish, only 10 were captured in ≥ 3% of non-null samples. Association analysis and canonical correspondence analysis of the samples-by-species (967×10) and samples-by-variables (967×15) data matrices revealed that the shallow, narrow, lotic, stony-pebbly channel microhabitat of riffles and runs was preferred by the progeny of substrate-spawning, substrate/plant-spawning and nest-guarding fishes. Moderately deeper and wider, sinuous channels, with slowto-moderate water velocities and medium-sized substrata were also favourable to progeny of substrate spawners. Assemblages of 0+ fish in deeper, wider, silted, trapezoidal-shaped channels with slow-to-lentic flowing water, i.e. channelised and regulated, were dominated by ubiquitous (plant/substrate) spawners.

Protection in simian immunodeficiency virus-vaccinated monkeys correlates with anti-HLA class I antibody response.

Abstract: Our earlier reports demonstrated that Cynomolgus macaques vaccinated with either inactivated partially purified simian immunodeficiency virus (SIV), fixed SIV-infected C8166 (a human T lymphoblastoid cell line) cells, or fixed uninfected C8166 cells can be protected against a challenge infection with the 32H isolate of SIVmac 251 (grown in C8166) (Stott, E. J., W. L. Chan, K. H. G. Mills, M. Page, F. Taffs, M. Cranage, P. Greenway, and P. Kitchin. 1990. Lancet. 336:1538; Stott, E. J., P. A. Kitchin, M. Page, B. Flanagan, L. F. Taffs, W. L. Chan, K. H. G. Mills, P. Silvera, and A. Rodgers. 1991. Nature [Lond.]. 353:393). Protection is correlated with the levels of antibody response to cellular antigens in the human cells from which the virus immunogen was grown. However, the mechanism of protection is unclear. We report here the analysis of sera from these protected monkeys and demonstrate that there is positive correlation of protection with antibody response to the HLA class I molecule.

Cytokine inter-relationships and their association with disease activity in arthritis

Abstract: In order to investigate the relationships between cytokine production and arthritic disease we have determined the concentrations of immunoreactive interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-6, tumour necrosis factor-alpha (TNF-alpha), interferon-alpha (IFN-alpha), IFN-gamma, and soluble IL-2-receptor (sIL-2R), as well as bioactive IL-1 and IL-6, in synovial fluids (SF) and plasma of patients with a variety of arthritides. Careful assay revealed only minimal concentrations of IL-1, particularly its biologically active form, in SF. No IL-1 was detectable in the plasma of patients that had IL-1 in their SF. Concentrations of both immunoreactive IL-1 beta and TNF-alpha in SF of rheumatoid arthritis (RA) patients were significantly higher than those in SF from patients with other inflammatory arthritides or osteoarthritis (OA). IL-6 and sIL-2R concentrations in both SF and plasma were higher in RA patients than in OA patients, and were significantly correlated. Approximately half of the SF from patients with all arthropathies contained detectable IFN-alpha, whilst IFN-Y was present in less than 10%. There were significant associations between IL-6, sIL-2R, IL-1 beta, TNF-alpha and IFN-alpha. The concentration of these cytokines, where detectable, was also related to leukocyte counts in the SF, as well as to parameters assessing local and systemic disease activity. Although IL-6 was the cytokine most clearly related to other cytokines, and to parameters assessing disease activity, the relationship between general articular disease activity and IL-6 was only evident in patients with arthropathies other than rheumatoid arthritis.

A comparison of 3-year-olds' caries experience in 1973, 1981 and 1989 in a Hertfordshire town, related to family behaviour and social class.

Abstract: The teeth of three samples of 3-year-old children were examined in the same fashion over two 8-year periods in a predominantly 'middle-class' town in Hertfordshire. After correcting for the changing social class structure of the town, mean dmft fell by 60% over the first period and by 29% over the second period, so the rate of improvement is decreasing. Improvements in caries levels have taken place in all the social classes except for a slight deterioration in social classes IV + V between 1981 and 1989. Ninety-six per cent of social class I + II children, but only 72% of social class IV + V children were caries-free. After falling from 8% to 1% between 1973 and 1981, the proportion of children with rampant labial caries increased to 4% in 1989. More children now visit a dentist for a check-up before the age of 4 years, more start toothbrushing at an earlier age and with greater frequency, and more are given fluoride supplements. Generally, infant feeding practices have continued to improve, although more mothers reported using a comforter bottle. Some of these practices are still strongly class-related, with manual social class families adopting less favourable behaviour. In inner city areas, family preventive behaviour and dental health is likely to be poorer.

Paralytic poliomyelitis in England and Wales, 1985-91.

Abstract: OBJECTIVES--To ascertain all cases of paralytic poliomyelitis in England and Wales during 1985-91 and to determine the source of infection in each case. DESIGN--Descriptive study of cases reported between 1985 and 1991. SETTING--All health districts in England and Wales. SUBJECTS--Patients normally resident in England and Wales whose clinical features were consistent with paralytic poliomyelitis or with laboratory evidence of recent poliovirus infection and compatible symptoms. MAIN OUTCOME MEASURES--Clinical, epidemiological, and laboratory features in identified cases. RESULTS--Of 54 suspected cases of poliomyelitis, 33 were excluded, leaving 21 cases, of which 13 were vaccine associated (nine recipient and four contact) cases, five were imported cases, and three were cases whose source of infection was unknown. No cases due to indigenous wild polioviruses were identified; two were imported cases due to wild viruses. One patient died during the acute phase of the illness, and two children with previously unrecognised severe congenital immune deficiency died between one and two months after the onset of paralysis after the first or second dose of oral polio vaccine. The estimated risk of vaccine associated paralysis is 1.46 per million for the first dose, 0.49 for the second, zero for the third and fourth doses, and 0.33 for the fifth. CONCLUSIONS--Indigenous wild poliovirus seems to have been eradicated, although wild virus may be imported; improved surveillance of suspected cases including immediate notification and characterisation of the virus to ensure that eradication is maintained is essential.

Design of infrared hybrid refractive-diffractive lenses.

Abstract: Hybrid refractive-diffractive elements offer a similar level of aberration control to the conventional doublet with approximately half the volume of material. The design principles of infrared elements are discussed. It is shown that, in order to match the performance of the conventional doublet, a general meniscus hybrid with an aspheric surface is required. The potential advantages are illustrated to good effect by a series of design examples, including a Petzval objective for the 3-5-microm band.

Inhibition by salmeterol of increased vascular permeability and granulocyte accumulation in guinea-pig lung and skin.

Abstract: 1. The long-acting beta 2-adrenoceptor agonist, salmeterol has been evaluated for its anti-inflammatory effects in the guinea-pig lung and skin. 2. Salmeterol, administered in bronchodilator doses to conscious guinea-pigs by both oral (0.01-1.0 mg kg-1) and inhaled (nebulizer concentration, 0.001-1.0 mg ml-1) routes, inhibited histamine-induced plasma protein extravasation (PPE) into the airway lumen. 3. Inhibition of PPE by salmeterol was long-lasting (greater than 6 h) and was inhibited by prior administration of propranolol (1 mg kg-1, s.c.), indicating an effect mediated by beta-adrenoceptors. 4. Inhaled salbutamol (nebulizer concentration, 0.001-1.0 mg ml-1) also inhibited PPE in guinea-pig lung but, in contrast to salmeterol, this effect was short-lived with substantial loss of activity 2 h after administration. 5. Inhaled salmeterol (0.1 mg ml-1) and salbutamol (1.0 mg ml-1) inhibited the accumulation of neutrophils in guinea-pig lung in response to lipopolysaccharide (100 micrograms ml-1). Salmeterol, but not salbutamol, inhibited the infiltration of eosinophils into the airway lumen in response to platelet activating factor (100 micrograms ml-1). These effects of salmeterol were blocked by prior administration of propranolol (5 mg kg-1, s.c.), indicating that they were also beta-adrenoceptor-mediated. 6. Oral salmeterol (10 mg kg-1, p.o.), but not salbutamol (10 and 100 mg kg-1, p.o.), inhibited zymosan-induced granulocyte accumulation and PPE in guinea-pig skin. Lower doses of salmeterol (0.1 and 1 mg kg-1) inhibited PPE, but not granulocyte accumulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Flotation In Water Treatment

Abstract: Dissolved-air flotation is a very effective solid-liquid separation process used in water treatment, as an alternative to sedimentation, to lower the solids concentrations before granular filtration. This enables filters to be operated more effectively and cost efficiently to produce a filtered water quality suitable, after disinfection, for potable supply. Dissolved-air flotation has been specifically developed for the treatment of algal laden and coloured waters. The flocs produced by the treatment of these waters have a low settling velocity, particularly when the water temperature is low and even when polyelectrolytes are added. Treating these waters, flotation requires smaller tanks and produces better treated water quality, compared to sedimentation. Dissolved-air flotation has become accepted as an alternative to sedimentation, in particular in the Scandinavian countries and the United Kingdom, with more than 50 plants in operation or under construction. The largest dissolved-air flotation plant currently being constructed is the 315 Ml/day Frankley water treatment works in the UK.

A condom applicator

Abstract: A condom applicator (2) comprising a rolled up condom (4) and a ring member (6) for applying the condom (4) by unrolling it over a penis, the ring member comprising a side wall (8), a flat portion (10), a first lip (12), a second lip (16), and first and second ends (18, 20) which are joined together by a frangible joint (22) which forms the ring member (6) into a complete ring in order to retain the condom (4) in position prior to use of the condom applicator (2) and which breaks during use of the condom applicator (2), and the ring member (6) being constructed to control the tendency of the first and the second ends (18, 20) to twist with respect to each other after the frangible joint (22) has been broken.

A 5-HT4-like receptor in human left atrium.

Abstract: The effects of 5-hydroxytryptamine (5-HT) on left atrial preparations obtained from 5 patients with terminal heart failure who were undergoing heart transplant surgery were investigated. The preparations were paced under isometric conditions. In the presence of (−)-pindolol I pmol/l (to block β-adrenoceptors) and cocaine 6 gmol/l (to block tissue uptake of 5-HT) 5-HT increased contractile force with a pEC50 of 7.0. The maximum effect of 5-HT amounted to 24.5% of that caused by a maximally effective concentration of (−)-isoprenaline (200 μmol/l) and 25% of that caused by 6.75 mmol/l CaCl2. The, effects of 5-HT were competitively antagonised by 3α-tropanyl-1H-indole-3-carboxylate (ICS 205–930) with a pKB of 6.8. The effects of 5-HT on cyclic AMP levels and cyclic AMP-dependent protein kinase activity were also studied using left atrial tissues from one of the patients; 5-HT increased the cyclic AMP content and stimulated the kinase. The results are consistent with the existence of a human left atrial 5-HT receptor which is similar to the recently identified human right atrial 5-HT receptor that resembles the 5-HT4 receptor. The left atrial 5-HT4-like receptor is functional in tissues obtained from patients with terminal heart failure.

Pathogenicity of the entomogenous, hyphomycete fungus, Metarhizium anisopliae against the chrysomelid beetles Psylliodes chrysocephala and Phaedon cochleariae

Abstract: Susceptibility of the mustard beetle (Phaedon cochleariae) and the cabbage stem flea beetle (Psylliodes chrysocephala) to six isolates of the entomogenous, hyphomycete fungus Metarhizium anisopliae, was investigated. A farther six isolates were assayed against P. cochleariae only. The isolates originated from hosts of various insect orders. Five of the six isolates tested against P. chrysocephala and P. cochleariae were infective for both species whereas one isolate, V107, was non‐pathogenic to both. The level of virulence of different M. anisopliae isolates for these chrysomelid beetles varied considerably. Isolates V90 and V93 were highly virulent to P. chrysocephala and P. cochleariae respectively but were significantly less virulent against the alternate host species. The LT50 of isolate V90 for P. chrysocephala was 7 days at 4 x 107 conidia/ml and its LC50 value was 16 x 105 conidia/ml. The LT50 of V93 for P. cochleariae was approximately 8 days at 4 X 108 conidia/ml and its LC50 value was 3 x 107 co...

Solid pharmaceutical composition

Abstract: A solid pharmaceutical composition for release of a biologically active substance into a desired aqueous environment, containing a core and an outer layer, said core comprising between 17 and 93% by weight of the biologically active substance, between 0.01 and 7% by weight of a water swellable polymer material and between 0 and 83% of one or more accessory ingredients, relative to the total weight of the core; and the outer layer comprising between 25 and 75% by weight of the biologically active substance, between 25 and 75% by weight of a material for enabling rapid dispersion of the outer layer into the aqueous environment and 0 to 50% by weight of one or more accessory ingredients, relative to the total weight of the outer layer. The composition is preferably formulated as a bolus for veterinary use.

Generation of a ribosomal DNA probe by PCR and its use in identification of fungi within the Gaeumannomyces‐Phialophora complex

Abstract: The polymerase chain reaction (PCR) was used to amplify a ribosomal DNA fragment from Gaeumannomyces graminis. This fragment was labelled and tested for its usefulness as a probe in restriction fragment length polymorphism (RFLP) studies of fungi within the Gaeumannomyces-Phialophora complex. When the probe was hybridized to Eco RI digests of DNA from these fungi, there were consistent band pattern differences between the three varieties of G. graminis (tritici, avenae and graminis). This method of probe production, which is more rapid than many others currently used, has considerable potential for use in the identification of these organisms, and may also be applicable to other groups of fungi.

Interspecific differences in the nematode surface coat between Meloidogyne incognita and M. arenaria related to the adhesion of the bacterium Pasteuria penetrans

Abstract: Spores of the bacterium Pasteuria penetrans adhered to second-stage juveniles of both Meloidogyne incognita and M. arenaria, but in standard attachment assays far fewer adhered to the latter species. Similarly, a polyclonal antibody was shown not to recognize the surface coat of M. arenaria but did recognize the surface coat of M. incognita. Although the incubation of whole, intact 2nd-stage juveniles of M. incognita in a series of detergents and protein-denaturing agents at room temperature did not reduce the number of spores adhering after exposure to the bacterium, incubation in buffer (PBS) alone at 100 °C for 2 min did. Immunoblotting of cuticle extracts onto nitrocellulose and probing the blots with antibody showed that the antibody recognized a large protein of Mr 80 kDa and a series of smaller proteins of approximately 43 kDa on M. incognita which were not recognized in extracts from M. arenaria. As incubation of the 2nd-stage juveniles in antibody prohibited spore attachment it is suggested that these proteins may be involved in spore adhesion. Large differences exist between M. incognita and M. arenaria in the amounts of surface-associated proteins on the 2nd-stage juvenile cuticle.

Effect of sumatriptan, a selective 5-HT1-like receptor agonist, on pial vessel diameter in anaesthetised cats

Abstract: The action of sumatriptan, a selective 5-HT1-like receptor agonist that is effective for the acute treatment of migraine, was compared on pial vessel diameter following perivascular or intravenous ...