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S Charlton

Publications and source records attributed to S Charlton.

16 recordsLinked to original sources
PubMed2006

Distribution and clearance of bioadhesive formulations from the olfactory region in man: effect of polymer type and nasal delivery device.

There is an increasing need to identify novel approaches by which to improve the efficiency of drug transport from the nasal cavity (olfactory region) to the CNS, especially for treatment of central nervous system disorders. It is suggested, that one approach is the combination of active targeting of a bioadhesive formulation, that will retain the drug at the absorption site, potentially in combination with, an absorption enhancer. Two low methylated pectins, LM-5 and LM-12 were selected for evaluation as drug delivery systems, due to their ability to gel in the nasal cavity and their bioadhesive characteristics, together with chitosan G210, which acts both as a bioadhesive material and as an efficient absorption enhancer. It was found that all of the bioadhesive formulations were able to reach the olfactory region in the nasal cavity of human volunteers when delivered using a simple nasal drop device. Furthermore, the formulations displayed a significantly increased residence time on the epithelial surface. This was in contrast to a non-bioadhesive control delivered with the same device. In contrast, a pectin formulation administered with a nasal spray system did not show an increase in residence time in the olfactory region. It was further shown that the reproducibility of olfactory delivery of a polymer formulation was significantly better intra-subject than inter-subject.

Adhesives↗
PubMed2004

Application of low dose rate pulsed fluoroscopy in cardiac pacing and electrophysiology: patient dose and image quality implications.

The performance of a low dose rate pulsed fluoroscopy option and its successful application to cardiac pacing and electrophysiology is reported. Low dose rate 6.25 frames per second pulsed fluoroscopy was made available in two catheter laboratories at a specialist cardiac centre in February 2003, and was adopted as the standard imaging technique for cardiac pacing procedures. The image quality was found to be considerably poorer than conventional modern units, being very similar to that which would have been accepted as adequate performance 20 years ago, but at less than one-tenth of the dose rate. No problems with the clinical acceptance of this imaging mode for cardiac pacing and electrophysiology have been reported. The already low median patient dose-area product for pacing at this cardiac centre was further reduced by 50% with the introduction of this fluoroscopy option.

Attitude of Health Personnel↗
PubMed2002

An association between the CTLA4 exon 1 polymorphism and early rheumatoid arthritis with autoimmune endocrinopathies.

OBJECTIVE: To examine the allelic association of the single nucleotide polymorphism (CTLA4A/G) in exon 1 of the cytotoxic T lymphocyte antigen-4 (CTLA4) gene with early rheumatoid arthritis (RA). METHODS: One hundred and twenty-three unrelated white probands with early RA from the north-east of England and 349 local ethnically matched controls were studied. The CTLA4A/G polymorphism was genotyped with a polymerase chain reaction (PCR) method and digestion with the restriction enzyme Bst71I. Probands were also screened by allele-specific PCR for alleles HLA DRB1*01 and DRB1*04. RESULTS: The frequency of the G allele at CTLA4A/G was significantly increased in probands with early RA compared with controls [43 vs 36%; P=0.028, odds ratio (OR) 1.35, 95% confidence interval (CI) 1.01-1.82]. Most of this increased frequency was attributable to RA individuals with coexisting autoimmune thyroid disease or type 1 diabetes (58 vs 36% in controls; P=0.005, OR 2.50, CI 1.29-4.84). The frequency of the G allele in RA patients without autoimmune endocrinopathy was 40%, which was not significantly different from that in controls (P=0.140). CONCLUSION: The association between the CTLA4 G allele and early RA is largely explained by individuals with RA who have coexisting autoimmune endocrinopathies.

Abatacept↗
PubMed1999

Characterization of the exosporium of Bacillus cereus.

Exosporium components from endospores of Bacillus cereus ATCC 10876 were purified and separated by gel electrophoresis. Several of the proteins for which N-terminal sequences were recovered were found to have homologues in protein databases which have been demonstrated to have enzymic activity in other organisms. Amongst these is a zinc metalloprotease, immune inhibitor A, already described in B. thuringiensis. This has been shown to be present in an active 73 kDa form on the exosporium of B. cereus. Other proteins associated with the exosporium include the molecular chaperone GroEL and a homologue of RocA (1-pyrroline-5-carboxylate dehydrogenase (EC 1.5.1.12)) of B. subtilis. Although these are unlikely to represent integral structural proteins of the exosporium, the observation that they are selectively present in the spore surface layer suggests that this layer may have functional significance.

Bacillus cereus↗
PubMed1997

Fungal galectins, sequence and specificity of two isolectins from Coprinus cinereus.

Galectins are members of a genetically related family of beta-galactoside-binding lectins. At least eight distinct mammalian galectins have been identified. More distantly related, but still conserving amino acid residues critical for carbohydrate-binding, are galectins in chicken, eel, frog, nematode, and sponge. Here we report that galectins are also expressed in a species of fungus, the inky cap mushroom, Coprinus cinereus. Two dimeric galectins are expressed during fruiting body formation which are 83% identical to each other in amino acid sequence and conserve all key residues shared by members of the galectin family. Unlike most galectins, these have no N-terminal post-translational modification and no cysteine residues. We expressed one of these as a recombinant protein and studied its carbohydrate-binding specificity using a novel nonradioactive assay. Binding specificity has been well studied for a number of other galectins, and like many of these, the recombinant C. cinereus galectin shows particular affinity for blood group A structures. These results demonstrate not only that the galectin gene family is evolutionarily much older than previously realized but also that fine specificity for complex saccharide structures has been conserved. Such conservation implies that galectins evolved to perform very basic cellular functions, presumably by interaction with glycoconjugates bearing complex lactoside carbohydrates resembling blood group A.

Amino Acid Sequence↗
PubMed1996

The effects of hemispheric asymmetries and depression on the perception of emotion.

The present study investigated hemispheric asymmetries in the perception of positive and negative emotion. The moderating effect of depression on hemispheric asymmetries was also examined. Forty undergraduates were presented with happy and sad faces using a bilateral visual half-field design. Subjects were classified as depressed or nondepressed based on scores on the Beck Depression Inventory. For nondepressed subjects, a right hemisphere advantage emerged for the speed of processing open and close-mouth sad expressions. For depressed subjects a right hemisphere advantage emerged for the speed of processing open-mouth sad expressions. In addition, a right hemisphere advantage for accuracy in identifying sad expressions was found for all subjects. No visual field differences were found for processing happy expressions.

Affect↗
PubMed1992

Cloning and differential expression during the sexual cycle of a meiotic endonuclease-encoding gene from the basidiomycete Coprinus cinereus.

The naturally synchronous meiosis of the fungus, Coprinus cinereus, provides an ideal system for the investigation of differential gene expression in relation to meiosis and fruiting body development. We have cloned a cDNA from the fruiting body of C. cinereus encoding the 12-kDa subunit of a meiotic endonuclease (mENase). The identification of the 12-kDa subunit cDNA clone was achieved by the mENase antiserum against a lambda gt11 cDNA expression library. It was confirmed by a direct match of the amino acid (aa) sequence obtained from purified 12-kDa polypeptide with the nucleotide sequence. Northern blot analysis using the cDNA clone as a probe showed that the mENase-encoding gene (MenA) for the 12-kDa subunit was expressed mainly in fruiting bodies and at a very low level in the asexual vegetative mycelium. In addition, it was differentially expressed in the early meiotic stages. The MenA transcript was most abundant in fruiting body primordia prior to the premeiotic S-phase; it remained high from karyogamy to early pachytene, declined drastically by late pachytene and diplotene, and was undetectable by sterigma stage. Western blot analysis showed that the mENase protein was produced at a very low level in mycelium; it was produced in great quantity during the early meiotic stages and decreased to a low level at the end of meiosis.

Amino Acid Sequence↗
PubMed1992

Lateral orientation, eye movements and dichotic listening.

Past studies have found that lateral orientation (eye or head turn) may influence hemispheric asymmetry on the dichotic listening task. The present work studied the effects of forced head and eye turn on a consonant-vowel dichotic test. Spontaneous conjugate lateral eye movements (CLEM) in response to questions were also measured. The subjects were 29 male and 25 female right-handed university students. The dichotic test was administered using a forced-attention method rather than free recall in order to control for attentional bias. As predicted, right lookers on the CLEM test, showed an enhanced right ear advantage while left lookers showed a diminished right ear advantage. This suggests that characteristic hemispheric arousal may enhance or inhibit asymmetry on perceptual laterality tests. No relationship was found between dichotic listening and forced head or eye turning. It was noted that past experiments may have failed to control for the attentional bias introduced by having the head or eyes turned to one direction.

Acoustic Stimulation↗
PubMed1990

Ginger root--a new antiemetic. The effect of ginger root on postoperative nausea and vomiting after major gynaecological surgery.

The effectiveness of ginger (Zingiber officinale) as an antiemetic agent was compared with placebo and metoclopramide in 60 women who had major gynaecological surgery in a double-blind, randomised study. There were statistically significantly fewer recorded incidences of nausea in the group that received ginger root compared with placebo (p less than 0.05). The number of incidences of nausea in the groups that received either ginger root or metoclopramide were similar. The administration of antiemetic after operation was significantly greater in the placebo group compared to the other two groups (p less than 0.05).

Adolescent↗
PubMed1989

Conjugate lateral eye movements: a second look.

It has been suggested that conjugate lateral eye movements (CLEM) are related to cerebral lateralization. Two types of research have developed: studies examining individual differences (hemisphericity) and studies examining the type of questions used to elicit eye movements (hemispheric specialization). In a 1978 review, Ehrlichman and Weinberger questioned the notion that CLEM is related to cerebral lateralization, particularly with regard to individual differences. However, since their review, a substantial number of studies have been published which are pertinent to the validity of CLEM. The following paper reviewed the validity of CLEM through three avenues, neurophysiological evidence, relationships with other measures of laterality and relation to spatial and verbal stimuli. Overall, it was concluded that there is sufficient evidence to support the CLEM model. Converging evidence from studies on EEG, electrical stimulation, ablation, brain damage, sodium amytal testing, blood flow, positron emission tomography, dichotic listening, and visual half fields was found to be, for the most part, supportive. The results for verbal and spatial task performance were mixed. Studies examining verbal abilities or a verbal to spatial comparison were generally supportive. The findings for spatial abilities alone were more equivocal. Evidence on question-type was found to be weak but positive, with about half the studies showing the predicted asymmetry and the other half reporting nonsignificant results. The implications of an interaction between hemisphericity or characteristic arousal and hemispheric specialization were also discussed.

Animals↗
PubMed1988

Torque and cerebral lateralization: a questionable link.

Past research has suggested that torque (the tendency to draw circles in a clockwise direction) may be indicative of less cerebral lateralization. This notion is based on the finding that left-handers demonstrate a greater incidence of torque than right-handers. The present study attempted to investigate this relationship using both conjugate lateral eye movements (CLEM) and handedness as indices of cerebral lateralization. Subjects were 40 male and 40 female right-handed and 16 male and 16 female nonright-handed university students. Consistent with past studies, torque was significantly related to handedness, with nonright-handers demonstrating a greater incidence of torque. However, no relationship between torque and CLEM was found. On the basis of these findings, it is argued that the observed relationship between torque and handedness may be due more to muscle mechanics of the hands rather than any relationship with cerebral lateralization.

Adult↗
PubMed1976

A psychogeriatric assessment program. III. Clinical and experimental psychologic aspects.

Variables stemming from standard psychologic tests, psychophysiologic tests, and operant conditioning procedures were employed in assessing the status of 80 psychogeriatric patients with either organic brain syndromes or functional psychoses. Differences were observed in the responses between the two groups. In general, the performance of the patients with organic brain syndromes was more deviant than that of the patients with functional psychoses, and the performance of the hospitalized geriatric patients (regardless of diagnosis) was worse than that of the normal control groups.

Adolescent↗
PubMedDate not supplied

The impact of change on violent patients.

This article describes how a continuing care ward attempted to deal with an increase in levels of violence towards staff and looks at how changes that were taking place on the ward may have contributed to a reduction in this problem. Possible lessons for the future management of this group of patients and reduction of violence are drawn from the discussion.

Humans↗