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Biomedical subjects

R Nicol

Publications and source records attributed to R Nicol.

At least 19 recordsLinked to original sources
PubMed2004

Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests.

Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will work as a short-term repellent and feeding deterrent. It is recommended that the use of Piper extracts be restricted to small-scale spot treatments in residential areas where insect pest outbreaks have occurred.

Animals↗
PubMed2000

Mental health needs and services for severely troubled and troubling young people including young offenders in an N.H.S. region.

Penal, social services, special education and health agencies in one National Health Service Region were screened for severely troubled and troublesome young people in need of mental health services. One hundred and sixteen detailed assessments were undertaken on young people: 57 in "penal" and 59 in "welfare" establishments. Little difference was found between those in these two types of setting except that the "penal group" were much more likely to have high levels of violent behaviour and to have had more changes of placement. The needs for mental health care greatly outstripped supply. As part of this overall neglect, 11 of 15 young people with serious mental illnesses and all 13 who had suffered sexual abuse in the sample were not receiving appropriate treatment. A tentative estimate of the size of the problem in the region yielded a rate of around 11.4 per million with very severe disorder but this is probably an under estimate. The effectiveness of treatment for the problems of these young people is discussed and a possible structure for a service is explored.

Adolescent↗
PubMed1999

Association of specific DNA binding and transcriptional repression with the transforming and myogenic activities of c-Ski.

The ski oncogene encodes a transcription factor that induces both transformation and muscle differentiation in avian fibroblasts. The first 304 amino acids of chicken Ski, the transformation domain, are both necessary and sufficient to mediate these biological activities. Ski's biological duality is mirrored by its transcriptional activities: it coactivates or corepresses transcription depending on its interactions with other transcription factors. Ski represses transcription through specific binding to GTCTAGAC (GTCT element) but it possesses a transferable repression activity that can function independently of this DNA element. In this study, we locate this repression domain to the NH2-terminal two-thirds and the GTCT binding region to the COOH-terminal one-third of Ski's transformation domain. Mutations in the transformation domain of c-Ski reveal a strong correlation between GTCT-mediated transcriptional repression and the biological activities of transformation and myogenesis. We also show that a dimerization domain located at the COOH terminal end of the Ski protein increases its transforming activity and its binding to GTCTAGAC.

Animals↗
PubMed1998

A domain necessary for the transforming activity of SnoN is required for specific DNA binding, transcriptional repression and interaction with TAF(II)110.

sno is a member of the ski oncogene family and shares ski's ability to transform avian fibroblasts and induce muscle differentiation. Ski and Sno are nuclear proteins that form homodimers and heterodimers. Ski activates transcription of cellular and viral enhancers and we have identified a DNA binding site (GTCTAGAC) through which it represses transcription. In this work, we show that SnoN binds this site and represses transcription of reporters with this binding site as an upstream element. Using fusions with the Gal4-DNA binding domain in a heterologous reporter assay, we identify a tripartite repression domain in SnoN. A 107 amino acid stretch of the SnoN repression domain, that contains two of the subdomains, is closely related to the minimal region of Ski required for transformation. The third subdomain is unique to SnoN. By analysing deletions involving each of the subdomains, we show that subdomains II and III are also required for DNA binding and cellular transformation. We provide evidence for a quenching mechanism of transcriptional repression by which subdomain II binds to TAF(II)110.

Animals↗
PubMed1998

Transcriptional repression by v-Ski and c-Ski mediated by a specific DNA binding site.

The Ski oncoprotein has been shown to bind DNA and activate transcription in conjunction with other cellular factors. Because tumor cells or myogenic cells were used for those studies, it is not clear that those activities of Ski are related to its transforming ability. In this study, we use a nuclear extract of c-ski-transformed cells to identify a specific DNA binding site for Ski with the consensus sequence GTCTAGAC. We demonstrate that both c-Ski and v-Ski in nuclear extracts are components of complexes that bind specifically to this site. By evaluating the features of the sequence that are critical for binding, we show that binding is cooperative. Although Ski cannot bind to this sequence on its own, we use cross-linking with ultraviolet light to show that Ski binds to this site along with several unidentified cellular proteins. Furthermore, we find that Ski represses transcription either through upstream copies of this element or when brought to the promoter by a heterologous DNA binding domain. This is the first demonstration that Ski acts as a repressor rather than an activator and could provide new insights into regulation of gene expression by Ski.

Animals↗
PubMed1996

The British approach to child and adolescent psychiatry: a course for Russian postgraduates.

A two week course in Child and Adolescent Psychiatry was given in St. Petersburg as part of the partnership between the City's Child and Adolescent Psychiatry Service and Division of Child and Adolescent Psychiatry at Leicester University Medical School. In such a short course, it was necessary to focus on areas of particular importance to Russian practice. Areas chosen were: assessment and interviewing skills, psychosomatic concepts, mental retardation, suicide and self harm, attachment, behaviour therapy and adolescent problems. The course also offered practical demonstrations with Russian families. The response was favourable but assessment of how much the course added to knowledge was difficult.

Adolescent↗
PubMed1986

BCG osteitis: a case report.

Osteomyelitis of the left tibia of a two year old boy secondary to neonatal BCG immunisation is described. He made a good recovery following surgical debridement and anti-tuberculosis chemotherapy.

BCG Vaccine↗
PubMed1986

The use of the simplex method for the optimisation of non-linear functions on a laboratory microcomputer.

The use of the microcomputer for the processing of analytical data in the laboratory is currently increasing. However, computational methods which have been used successfully on minicomputers may not be suitable for microcomputer implementation due to the lack of available precision. This paper describes a technique, namely the simplex method, which may be successfully applied to the processing of laboratory data on an 8-bit microcomputer. The method is used to optimise a non-linear function in order to fit a curve to radioimmunoassay (RIA) and immunoradiometricassay (IRMA) data. The microcomputer package described has been tested on laboratory data and is currently in use in a clinical biochemistry laboratory.

Biometry↗
PubMed1986

A survey of the state of the art of clinical biochemistry laboratory computerisation.

This paper presents the results of a survey which was recently carried out in order to clarify the current 'state of the art' regarding the use of computers in hospital biochemistry laboratories. Information was obtained by means of a questionnaire which was mailed to a sample of United Kingdom hospital laboratories. The results obtained from the analysis of the data from the questionnaire replies are presented, and conclusions are drawn regarding the implications of hospital laboratory computerisation.

Chemistry, Clinical↗
PubMed1985

A robust microcomputer routine for the identification of outlying and influential points in radioimmunoassay standard curves.

This paper describes a suite of robust logit-log optimization routines for the fitting of a linear relation to laboratory data. The microcomputer routines assign a weighting value to each data point corresponding to the relative importance of that point. This procedure ensures that the routines identify and deal with any outlying data points. The routines are designed to generate the results of both a standard, unweighted least-squares algorithm and a robust, weighted algorithm thus providing the laboratory analyst with invaluable information concerning the data and the fitted relation. The routines are thoroughly tested on "perfect" and perturbed laboratory data.

Biometry↗
PubMed1985

The relevance of the multiple criterion screen to an adolescent population.

The 4th- and 5th-year pupils of four large comprehensive schools, which were broadly typical of the schools serving an urban population, were screened using a multiple criterion approach. The screen results were compared with those found in a younger population drawn from the same area, and a similar rate of efficiency was found. However, in the adolescent age group the screen was more accurate at detecting true negative cases (specificity) but less able to identify true positive cases (sensitivity). Overall, the multiple criterion screen proved more efficient than a variety of single screen criteria, and the findings also suggest that certain screen measures used in adolescence may be more effective at identifying disturbed girls while others are more effective at identifying disturbed boys. This confirms the principle that the choice of screening instruments must be made with reference to their proposed use.

Adolescent↗
PubMed1975

Measurement of the immune response to an allograft: amino acid incorporation by peripheral white blood cells in man.

The uptake in vitro of 3H-thymidine and of 3H-uridine by white blood cells freshly taken from the recipients of renal transplants has been followed at regular intervals during the period of the patients' hospitalization. In addition, groups of subjects without renal failure undergoing operation and of patients on chronic dialysis have been studied. Of 33 patients undergoing rejection of their kidney, 28 showed a marked rise in the incorporation of thymidine over the period of rejection. However, a similar rise appears to accompany episodes of inter-current infection.

Graft Rejection↗