Showing papers by "University of Nottingham published in 1988"

Antisense RNA inhibition of polygalacturonase gene expression in transgenic tomatoes

Abstract: Regulation of expression of specific genes by antisense RNA is a naturally occurring mechanism in bacteria1,2, although gene regulation by this mechanism has not yet been observed in higher eukaryotes. However, antisense RNA has been shown to reduce expression of specific genes when injected into frog oocytes3 and Drosophila embryos4. Inhibition of expression of artificially introduced genes has been demonstrated by transient expression of antisense RNA constructs in mammalian cells5,6, and plant protoplasts7, and by stable expression in transgenic plants8. Here, we report a striking inhibition of expression of the endogenous, developmentally regulated gene for polygalacturonase in stably transformed tomato expressing antisense RNA.

Increased iron (III) and total iron content in post mortem substantia nigra of parkinsonian brain.

Abstract: Significant differences in the content of iron (III) and total iron were found in post mortem substantia nigra of Parkinson's disease There was an increase of 176% in the levels of total iron and 255% of iron (III) in the substantia nigra of the parkinsonian patients compared to age matched controls In the cortex (Brodmann area 21), hippocampus, putamen, and globus pallidus there was no significant difference in the levels of iron (III) and total iron Thus the changes in total iron, iron (III) and the iron (II)/iron (III) ratio in the parkinsonian substantia nigra are likely to be involved in the pathophysiology and treatment of this disorder

Ubiquitin is a common factor in intermediate filament inclusion bodies of diverse type in man, including those of Parkinson's disease, Pick's disease, and Alzheimer's disease, as well as Rosenthal fibres in cerebellar astrocytomas, cytoplasmic bodies in muscle, and mallory bodies in alcoholic liver disease.

Abstract: Polyclonal antibodies were raised which have a high affinity for conjugated ubiquitin. Immunocytochemistry was performed on paraffin sections of tissues showing well-characterized inclusion bodies. Ubiquitin was found as a component of the intermediate filament inclusion bodies characteristic of several major diseases including Lewy bodies of Parkinson's disease, Pick bodies of Pick's disease, Mallory bodies of alcoholic liver disease, cytoplasmic bodies of a specific myopathy, and Rosenthal fibres within astrocytes. Ubiquitin was also present in the three histological lesions characteristic of Alzheimer's disease. These observations suggest a fundamental role for ubiquitin in the formation of intermediate filament inclusion bodies in man, and have implications regarding the pathogenesis of these important diseases.

A prospective study of severe mental disorder in Afro-Caribbean patients

Abstract: Several previous studies have reported increased rates of schizophrenia among Afro-Caribbean immigrants, although doubt has been cast upon the value of case-note diagnoses and retrospective case-finding. A prospective study was therefore undertaken, including all patients of Afro-Caribbean ethnic origin with a first onset psychosis presenting to the psychiatric services from a defined catchment area. Utilizing several diagnostic classifications, rates for schizophrenia were found to be substantially increased in the Afro-Caribbean community, and especially in the 'second generation' British born. Mode of onset and symptom profiles of psychoses suggest that atypical syndromes, and by implication 'misdiagnoses', do not account for reported higher rates of schizophrenic illness in these patients.

The long-term outcome of Maudsley depressives.

Abstract: Eighty-nine consecutive admissions with primary depressive illness were prospectively ascertained and diagnosed in 1965-66 by R. E. Kendell, who also allocated each a position on a neurotic-psychotic continuum on the basis of previous discriminant function analysis. In 1983-84, 94% of the survivors were personally interviewed by a psychiatrist blind to index admission data. Operational outcome criteria were employed and longitudinal data were established for 98% of the series. Mortality risk was doubled overall, and increased sevenfold for women under 40 years at index admission. Less than one-fifth of the survivors had remained well, and over one-third of the series suffered unnatural death or severe chronic distress and handicap. Patients whose index episode marked their first psychiatric contact had a 50% chance of readmission within their lifetime, but those with previous admissions had a 50% chance of readmission within three years. Readmissions occurred even after 12 years of being symptom-free, and conversely patients recovered after as long as 15 years of illness. There was a high incidence of other disorders (schizoaffective disorder, alcoholism, schizophrenia), and only four patients showed pure recurrent unipolar histories. Patients at the psychotic end of the continuum were more likely to be readmitted and to have very poor outcomes.

Transgenic rice plants produced by electroporation-mediated plasmid uptake into protoplasts

Abstract: Transgenic rice plants have been regenerated by somatic embryogenesis from cell suspension derived protoplasts electroporated with plasmid carrying the NPTII gene under the control of the 35S promoter from cauliflower mosaic virus. Heat shock of protoplasts prior to electroporation maximised the throughput of kanamycin resistant colonies. Omission of kanamycin from the medium for plant regeneration was essential for the recovery of transgenic rice plants carrying the NPTII gene. This report of the production of kanamycin resistant transgenic rice plants establishes the use of protoplasts for rice genetic engineering.

Duration of effectiveness of pertussis vaccine: evidence from a 10 year community study

Abstract: A 10 year study of whooping cough in a discrete general practice community was performed to assess longitudinally the efficacy of pertussis vaccine from one to seven years after immunisation. Of the 436 cases of whooping cough over 10 years, 326 occurred in children aged 1-7 years. The rate of immunisation was known for each cohort of children born during each year, and the attack rate of whooping cough was thus calculated for those immunised and unimmunized. The attack rates were highest in those cohorts exposed to the epidemics of 1977-9, 1981-3, and 1985-7. The efficacy of the vaccine was calculated as a percentage as (attack rate in unimmunized group--attack rate in immunised group) x 100/attack rate in unimmunized group. It fell from 100% in the first year to 46% in the seventh, being 84% in the fourth and only 52% in the fifth. Thus the pertussis vaccine or its schedule of use does not seem to provide sufficient herd immunity to prevent outbreaks of whooping cough. Matters might be improved if vaccination against pertussis were included in the preschool immunisation programme.

Hormonal regulation of ripening in the strawberry, a non-climacteric fruit.

Abstract: Anthocyanin accumulation is one measure of ripening in the strawberry (Fragaria ananassa Duch), a non-climacteric fruit Neither aminoethoxyvinylglycine, an inhibitor of 1-aminocyclopropane carboxylic acid synthase, nor inhibitors of ethylene action (silver, norbornadiene) affected anthocyanin accumulation in ripening fruit When the achenes were removed from one half of an unripe fruit there was an accelerated accumulation of anthocyanin and induction of phenylalanine ammonia lyase on the de-achened portion of the ripening fruit These effects of achene removal could be prevented by the application of the synthetic auxins 1-naphthaleneacetic acid or 2,4-dichlorophenoxyacetic acid to the de-achened surface The introduction of 1-naphthalene acetic acid into intact unripe strawberry fruit through the peduncle delayed their subsequent ripening, as measured by the accumulation of anthocyanin, loss of chlorophyll and decrease in firmness These findings suggest that the decline in the concentration of auxin in the achenes as strawberry fruit mature modulates the rate of fruit ripening

The tomato polygalacturonase gene and ripening-specific expression in transgenic plants.

Abstract: Polygalacturonase (PG) is the major cell wall degrading enzyme of tomato fruit It is developmentally regulated and is synthesised de novo in ripening fruit Genomic clones encoding a PG gene of tomato (Lycopersicon esculentum Mill cv Ailsa Craig) have been isolated, mapped and sequenced The sequence of the protein-coding region is identical to that of a PG cDNA [20] Comparison of the cloned restriction fragments with genomic Southern data suggests that there may only be one gene for PG per haploid genome The PG gene, which covers approximately 7 kb, is interrupted by 8 intervening sequences ranging in size from 99 bp to 953 bp The transcription start point was identified by S1 mapping and primer extension analysis About 14 kb of 5′ flanking DNA has been sequenced This contains putative TATA and CAAT boxes and also direct repeat sequences A transcriptional fusion has been constructed between the putative 14 kb promoter fragment and the chloramphenicol acetyl transferase (CAT) gene Constructs containing this gene have been transferred to tomato using binary vectors Regenerated transgenic plants express CAT in ripe tomato fruit, but not in unripe tomatoes, leaves, or roots

How Children Think and Learn: The Social Contexts of Cognitive Development

Abstract: Introduction: From Pavlov to Piaget. 1. Images of Childhood and their Reflection in Teaching. 2. A Decade of Development. 3. Are there Stages of Development? 4. Learning how to Think and Learn. 5. Language and Learning. 6. Making Sense. 7. The Literate Mind. 8. The Mathematical Mind. 9. Education and Educatability. Bibliography.

Five years of heartsink patients in general practice.

Abstract: "Heartsink" patients exasperate, defeat, and overwhelm their doctors by their behaviour. A group of such patients was followed up over five years in a general practice, and this paper describes what happened to them. As a group they were often in employment and in stable relationships, though women were over represented. Half the group were subjected to a management plan which seemed to make them less heartsink over the five year period. While heartsink patients often have serious medical problems, they are a disparate group of individuals whose only common thread seems to be the distress they cause their doctor and the practice. Heartsink as a phenomenon has features that are unique to general practice.

Muscle strength in the triceps surae and objectively measured customary walking activity in men and women over 65 years of age

Abstract: 1. Objective measurements of the maximal voluntary strength of triceps surae and the amount and speed of customary walking have been made in 56 men and 66 women aged over 65 years, who were living independently. 2. Strength was measured using a dynamometer based upon a hydraulic system (Bourdon tube). Walking was assessed, for amount using a mechanical accelerometer (pedometer) over a week, and for speed using a self-paced test for normal walking over 100 m on the level. The reliability and validity of these methods has been described. 3. The men were significantly stronger (1128 +/- 206 vs 873 +/- 177 N) even after adjustment for body weight; their amount of walking was similar to that of women, but they walked significantly faster (4.8 +/- 0.6 vs 4.2 +/- 0.6 km/h). Men were significantly more active in leisure pursuits (as assessed by questionnaire). 4. Significant associations between strength and chosen normal walking speed were found for both sexes (r = 0.41, P less than 0.001 for men and r = 0.36, P less than 0.01 for women). The amount of walking (daily stepscore as a mean from 7 consecutive days recorded) was significantly but less strongly correlated with strength (r = 0.30, P less than 0.05) in the men only. 5. Multiple regression analysis showed that in men neither age nor amount of walking had any further effect in addition to speed, but in women age had an additional effect (multiple R = 0.48). 6. An association has been demonstrated which raises the possibility of reversing loss of muscle strength through increased daily activity.

Clinical Pharmacokinetics of Ketoconazole

Abstract: Ketoconazole, a synthetic imidazole antifungal, is effective for superficial fungal infections, genital candidosis and chronic mucocutaneous candidosis, and has been used in immunocompromised patients and advanced prostatic carcinoma.

The mechanism of operation of tin(iv) oxide carbon monoxide sensors

Abstract: The electrical properties of tin(iv) oxide render it an excellent material for the detection of very low levels of carbon monoxide, and several devices based on sintered pellets of SnO2 are commercially available1,2. Investigations of the operation of such sensors have generally been restricted to studies of the electrical behaviour of the oxide and little attention has been paid to the relationship between the surface adsorption phenomena and electrical changes in the bulk oxide. These studies3 demonstrated the consistency of a model in which conductance is effectively controlled by the population of negatively charged oxygen adsorbates. The chemical reactions occurring at the oxide surface, although unsubstantiated, have been assumed to involve CO adsorption, desorption of CO2 (which produces an increase in conductance) and replenishment of the resulting surface oxygen vacancy by adsorption of molecular oxygen4. Here we describe experiments in which the nature of the surface species adsorbed into tin(iv) oxide from atmospheres containing low levels of carbon monoxide is monitored using transmission infrared spectroscopy while simultaneously measuring the electrical changes produced in the bulk oxide. The data demonstrate the effect of heat treatment on the formation of adsorbate species and the mutual interdependence of adsorbate species and bulk oxide electrical conductance. This relationship is important both for sensor operation and heterogeneous catalysis.

A Study of Students' Understanding of Electricity in Five European Countries.

Abstract: This paper describes a study of the understanding of basic electrical concepts shown by 15‐17 year‐old students in England, France, The Netherlands, Sweden and West Germany, the same objective test having been administered to samples of students in each of these countries. When within‐country results were averaged across student groups the between‐country differences on many aspects of this subject were quite small. Those electrical principles which yielded significant differences fell into two main groups, one concerned with current, flow of charge and energy, the other with voltage and its relationship to current. The consistency with which these significant differences emerged across a range of problems concerning related principles suggests that these represent real differences between the outcomes of teaching across the five countries but the causes of these differences are not yet clear. Despite the differences that have emerged, the overall impression which the results convey is of substantially th...

Detection of DNA "fingerprints" of cultivated rice by hybridization with a human minisatellite DNA probe

Abstract: A human minisatellite DNA probe detects several restriction fragment length polymorphisms in cultivars of Asian and African rice. Certain fragments appear to be inherited in a Mendelian fashion and may represent unlinked loci. The hybridization patterns appear to be cultivar-specific and largely unchanged after the regeneration of plants from tissue culture. The results suggest that these regions of the rice genome may be used to generate cultivar-specific DNA fingerprints. The demonstration of similarity between a human minisatellite sequence and polymorphic regions in the rice genome suggests that such regions also occur in the genomes of many other plant species.

Factors affecting early unplanned readmission of elderly patients to hospital.

Abstract: A random sample of 133 elderly patients who had an unplanned readmission to a district general hospital within 28 days of discharge from hospital was studied and compared with a matched control sample of patients who were not readmitted. The total group was drawn from all specialties in the hospital, and by interviewing the patients, their carers, the ward sisters, and the patients9 general practitioners the factors causing early unplanned readmission for each patient were identified. Seven possible principal reasons were found: relapse of original condition, development of a new problem, carer problems, complications of the initial illness, need for terminal care, problems with medication, and problems with services. There were also contributory reasons, and it was usual for several of these to be present in each case. The unplanned readmission rate was 6%; the planned readmission rate was 3%. It was thought that unplanned readmission was avoidable for 78 (59%) patients. Patients in the study group and in the control group showed significant differences in certain characteristics--such as low income, previous hospital admission, already having nursing care, and admission by general practitioners--and this might help to identify patients who are likely to be readmitted in an emergency.

Prevalence, frequency, and duration of hypnotic drug use among the elderly living at home

Abstract: Details of consumption of hypnotic drugs derived from a nationally representative sample of elderly people were analysed in terms of the prevalence, duration, and likely frequency of use. Of 1020 randomly selected subjects aged 65 and over 16% (166) reported using (mainly benzodiazepine) hypnotic drugs, and of these 89% reported having taken such a drug the night before the interview. Most of these users (73%) had been taking hypnotic drugs for more than one year, with 25% reporting drug use for more than 10 years. These results suggest that for most elderly users of hypnotic drugs, patterns of consumption encourage the development of cumulative effects and benzodiazepine dependence.

Levels of customary physical activity among the old and the very old living at home.

Abstract: With an activity inventory designed specifically for use among elderly people, detailed profiles of customary physical activity were obtained from 507 old (aged 65-74 years) and 535 very old (aged 75 years and over) individuals randomly sampled from the community. Participation in four categories of activity was assessed: outdoor productive activities; indoor productive activities; leisure activities; and walking. Customary engagement in many activities was found to be low, age (old versus very old) and sex being among the most important determinants of participation. The method of assessment is described, and activity profiles normative for older age groups are presented.

The wilty tomato mutants flacca and sitiens are impaired in the oxidation of ABA‐aldehyde to ABA

Abstract: . Deuterium-labelled ABA-aldehyde was fed to various tomato genotypes. Normal and notabilis mutant plants incorporated substantial amounts of the label into ABA. In contrast, two ABA-deficient mutants, flacca and sitiens, reduced ABA-aldehyde to a mixture of cis- and trans-ABA alcohol rather than oxidizing it to ABA. It was concluded that ABA-aldehyde is the immediate precursor of ABA in higher plants. It appears that the flacca and sitiens lesions both act to block the last step of the ABA biosynthetic pathway. The mutant gene loci are likely to be involved in coding for different sub-units of the same dehydrogenase enzyme.