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T Roberts

Publications and source records attributed to T Roberts.

At least 37 records · Page 2Linked to original sources
PubMed2000

In-training assessment - its potential in enhancing clinical teaching.

CONTEXT: In-training assessment (ITA) has established its place alongside formative and summative assessment at both the undergraduate and postgraduate level. In this paper the authors aimed to identify those characteristics of ITA that could enhance clinical teaching. METHODS: A literature review and discussions by an expert working group at the Ninth Cambridge Conference identified the aspects of ITA that could enhance clinical teaching. RESULTS: The features of ITA identified included defining the specific benefits to the learner, teacher and institution, and highlighting the patient as the context for ITA and clinical teaching. The 'mapping' of a learner's progress towards the clinical teaching objectives by using multiple assessments over time, by multiple observers in both a systematic and opportunistic way correlates with the incremental nature of reaching clinical competence. CONCLUSIONS: The importance of ITA based on both direct and indirect evidence of what the learner actually does in the real clinical setting is emphasized. Particular attention is given to addressing concerns in the more controversial areas of assessor training, ratings and documentation for ITA. Areas for future research are also identified.

Clinical Clerkship↗
PubMed2000

Clinical teaching: maintaining an educational role for doctors in the new health care environment.

CONTEXT AND OBJECTIVES: Good clinical teaching is central to medical education but there is concern about maintaining this in contemporary, pressured health care environments. This paper aims to demonstrate that good clinical practice is at the heart of good clinical teaching. METHODS: Seven roles are used as a framework for analysing good clinical teaching. The roles are medical expert, communicator, collaborator, manager, advocate, scholar and professional. RESULTS: The analysis of clinical teaching and clinical practice demonstrates that they are closely linked. As experts, clinical teachers are involved in research, information retrieval and sharing of knowledge or teaching. Good communication with trainees, patients and colleagues defines teaching excellence. Clinicians can 'teach' collaboration by acting as role models and by encouraging learners to understand the responsibilities of other health professionals. As managers, clinicians can apply their skills to the effective management of learning resources. Similarly skills as advocates at the individual, community and population level can be passed on in educational encounters. The clinicians' responsibilities as scholars are most readily applied to teaching activities. Clinicians have clear roles in taking scholarly approaches to their practice and demonstrating them to others. CONCLUSION: Good clinical teaching is concerned with providing role models for good practice, making good practice visible and explaining it to trainees. This is the very basis of clinicians as professionals, the seventh role, and should be the foundation for the further development of clinicians as excellent clinical teachers.

Australia↗
PubMed2000

Characterization of conserved T- and B-cell epitopes in Plasmodium falciparum major merozoite surface protein 1.

Vaccines for P. falciparum will need to contain both T- and B-cell epitopes. Conserved epitopes are the most desirable, but they are often poorly immunogenic. The major merozoite surface protein 1 (MSP-1) is currently a leading vaccine candidate antigen. In this study, six peptides from conserved or partly conserved regions of MSP-1 were evaluated for immunogenicity in B10 congenic mice. Following immunization with the peptides, murine T cells were tested for the ability to proliferate in vitro and antibody responses to MSP-1 were evaluated in vivo. The results showed that one highly conserved sequence (MSP-1#1, VTHESYQELVKKLEALEDAV; located at amino acid positions 20 to 39) and one partly conserved sequence (MSP-1#23, GLFHKEKMILNEEEITTKGA; located at positions 44 to 63) contained both T- and B-cell epitopes. Immunization of mice with these peptides resulted in T-cell proliferation and enhanced production of antibody to MSP-1 upon exposure to merozoites. MSP-1#1 stimulated T-cell responses in three of the six strains of mice evaluated, whereas MSP-1#23 was immunogenic in only one strain. Immunization with the other four peptides resulted in T-cell responses to the peptides, but none of the resulting peptide-specific T cells recognized native MSP-1. These results demonstrate that two sequences located in the N terminus of MSP-1 can induce T- and B-cell responses following immunization in a murine model. Clearly, these sequences merit further consideration for inclusion in a vaccine for malaria.

Amino Acid Sequence↗
PubMed2000

Recent economic evaluations of antenatal screening: a systematic review and critique.

A systematic review of recent economic evaluations of antenatal screening was conducted. Relevant studies were identified from a number of sources including computerised databases, bibliographies of economic evaluations, and searches of unpublished manuscripts. Each study identified by the literature searches was categorised on the basis of its title and abstract. Studies considered relevant to the systematic review were obtained from libraries. The methodology, results, and policy implications of studies categorised as economic evaluations upon full review were documented. A total of 566 studies were identified by the literature searches, 41 of which were categorised as economic evaluations upon full review. The economic evaluations covered a range of antenatal screening practices, aimed mainly at the prevention of infectious diseases and fetal anomalies. The review highlighted the poor methodological quality of the bulk of economic evaluations of antenatal screening. The study design, data collection methods, and analysis and interpretation of results frequently violated methodological guidelines adopted by health economists. The review also highlighted the narrow definition of benefits adopted by this body of literature, with most studies reporting outcomes in terms of cases detected, cases of particular disorders prevented or, most often, costs averted. The conclusions arrived at differed by area of antenatal screening. There appeared to be clear economic arguments in favour of some forms of antenatal screening, for example, triple test screening for Down's syndrome. Other economic evaluations pertained to specific locations, which suggests that the results may not necessarily be generalizable to different settings. For all areas of antenatal screening, an updating of published economic evaluations may be required to account for evolving economic, epidemiological, and clinical effectiveness evidence.

Costs and Cost Analysis↗
PubMed2000

Auditory cortex accesses phonological categories: an MEG mismatch study.

The studies presented here use an adapted oddball paradigm to show evidence that representations of discrete phonological categories are available to the human auditory cortex. Brain activity was recorded using a 37-channel biomagnetometer while eight subjects listened passively to synthetic speech sounds. In the phonological condition, which contrasted stimuli from an acoustic /dae/-/tae/ continuum, a magnetic mismatch field (MMF) was elicited in a sequence of stimuli in which phonological categories occurred in a many-to-one ratio, but no acoustic many-to-one ratio was present. In order to isolate the contribution of phonological categories to the MMF responses, the acoustic parameter of voice onset time, which distinguished standard and deviant stimuli, was also varied within the standard and deviant categories. No MMF was elicited in the acoustic condition, in which the acoustic distribution of stimuli was identical to the first experiment, but the many-to-one distribution of phonological categories was removed. The design of these studies makes it possible to demonstrate the all-or-nothing property of phonological category membership. This approach contrasts with a number of previous studies of phonetic perception using the mismatch paradigm, which have demonstrated the graded property of enhanced acoustic discrimination at or near phonetic category boundaries.

Acoustic Stimulation↗
PubMed2000

An economic evaluation comparing two schedules of antenatal visits.

OBJECTIVES: To conduct an economic evaluation comparing a traditional antenatal visiting schedule (traditional care) with a reduced schedule of visits (new style care) for women at low risk of complications. METHODS: Economic evaluation using the results of a randomised controlled trial, the Antenatal Care Project. This took place between 1993 and 1994 in antenatal clinics in South East London and involved 2794 women at low risk of complications. RESULTS: The estimated baseline costs to the UK National Health Service (NHS) for the traditional schedule were 544 Pounds per woman, of which 251 Pounds occurred antenatally, with a range of 327-1203 Pounds per woman. The estimated baseline costs to the NHS for the reduced visit schedule was 563 Pounds per woman, of which 225 Pounds occurred antenatally, with a range of 274-1741 Pounds per woman. Savings from new style care that arose antenatally were offset by the greater numbers of babies in this group who required special or intensive care. Sensitivity analyses based on possible variations in unit costs and resource use and modelled postnatal stay showed considerable variation and substantial overlap in costs. CONCLUSIONS: Patterns of antenatal care involving fewer routine visits for women at low risk of complications are unlikely to result in savings to the Health Service. In addition, women who had the reduced schedule of care reported greater dissatisfaction with their care and poorer psychosocial outcomes which argues against reducing numbers of antenatal visits.

Cost-Benefit Analysis↗
PubMed2000

A new region of synteny between human chromosome 1p22 and mouse chromosome 5.

By constructing a physical map of the p22 region of human chromosome 1 we have been able to show the relative orientation of four genes; GFI1, NB4S/EVI5, RPL5 and DR1. Analysis of the mouse physical map shows that the murine orthologs of these genes are located on mouse chromosome 5. Through this analysis we have established a new region of synteny between mouse chromosome 5 and human chromosome region 1p22.

Animals↗
PubMed1999

Cortical auditory signal processing in poor readers.

Magnetoencephalographic responses recorded from auditory cortex evoked by brief and rapidly successive stimuli differed between adults with poor vs. good reading abilities in four important ways. First, the response amplitude evoked by short-duration acoustic stimuli was stronger in the post-stimulus time range of 150-200 ms in poor readers than in normal readers. Second, response amplitude to rapidly successive and brief stimuli that were identical or that differed significantly in frequency were substantially weaker in poor readers compared with controls, for interstimulus intervals of 100 or 200 ms, but not for an interstimulus interval of 500 ms. Third, this neurological deficit closely paralleled subjects' ability to distinguish between and to reconstruct the order of presentation of those stimulus sequences. Fourth, the average distributed response coherence evoked by rapidly successive stimuli was significantly weaker in the beta- and gamma-band frequency ranges (20-60 Hz) in poor readers, compared with controls. These results provide direct electrophysiological evidence supporting the hypothesis that reading disabilities are correlated with the abnormal neural representation of brief and rapidly successive sensory inputs, manifested in this study at the entry level of the cortical auditory/aural speech representational system(s).

Acoustic Stimulation↗
PubMed1999

Cutting edge: recruitment of the CD19/CD21 coreceptor to B cell antigen receptor is required for antigen-mediated expression of Bcl-2 by resting and cycling hen egg lysozyme transgenic B cells.

Recruitment of the CD19/CD21 coreceptor is thought to lower the threshold for effective signaling through the B cell Ag receptor. We provide evidence supporting a second role for coreceptor recruitment, and that is to enhance the survival/proliferative potential of the responding B cells. We show that B cell Ag receptor signaling in the absence of coreceptor recruitment induces cellular accumulation of the anti-apoptotic protein Bcl-xL, whereas CD19-mediated signals are required for Bcl-2 accumulation. The expression of both anti-apoptotic proteins correlates with the enhanced responsiveness of both resting and cycling B cells to growth-promoting signals delivered through CD40. These results provide further evidence for the necessity of coreceptor recruitment during Ag-dependent B cell activation and indicate that Ags derived from inflammatory sites function as better thymus-dependent Ags than their counterparts not coated with complement fragments.

Animals↗
PubMed1999

TTC4, a novel human gene containing the tetratricopeptide repeat and mapping to the region of chromosome 1p31 that is frequently deleted in sporadic breast cancer.

The 1p31 region shows loss of heterozygosity in up to 50% of human breast cancers, indicating the presence of a tumor suppressor gene in this location. We have mapped six novel ESTs to a 15-Mb contig of yeast artificial chromosomes spanning the critical region of 1p31. One of these ESTs was localized within the contig to the region most commonly undergoing loss of heterozygosity in breast cancer. The corresponding gene sequence for this EST was established by cDNA cloning and RACE procedures. This gene is 2 kb long and contains a tetratricopeptide repeat motif and a coiled-coil domain. This family of genes has been implicated in a wide variety of functions, including tumorigenesis. This is the fourth member of the human gene family, and so we have named this gene TTC4. Northern blot analysis demonstrates a ubiquitous pattern of gene expression that includes breast tissue. A preliminary screen of human breast cancer cell lines shows that TTC4 is expressed in all cases, but SSCP analysis of the coding region of this gene following RT-PCR failed to reveal any mutations. Clearly, because of its map location, a more extensive analysis is warranted to establish whether subtle mutations are present in breast cancers.

Amino Acid Sequence↗
PubMed1999

[Diagnosis of an intramyocardial hematoma via MRI after a traumatic myocardial infarct].

Traumatic cardiac lesions occur in about 30% of all traumatized patients, in most cases they are due to traffic accidents. We report a patient who suffered from a traumatic anterior wall infarction following a ski accident. Consecutively, an extended intramyocardial hemorrhage occurred. A left ventricular pseudoaneurysm was considered first by echocardiography. Using MRI, an intramyocaridal hemorrhage could be diagnosed because of a thin myocardial border surrounding the hematoma. Consecutively, the patient underwent CABG surgery as well as a resection of the intramyocardial hematoma. This diagnosis could be manifested surgically and histologically.

Aged↗
PubMed1999

Diurnal variation in saliva estriol level during pregnancy: a pilot study.

OBJECTIVE: The object of the study was to characterize daily values and patterns of salivary estriol levels during normal pregnancy at mid to late gestation. STUDY DESIGN: We measured salivary estriol levels in a clinical research center setting with an established enzyme-linked immunosorbent assay. Fourteen pregnant women (24-36 weeks' gestation) submitted unstimulated saliva samples hourly from 10:00 am until 10:00 pm and at midnight and 2:00, 4:00, 6:00, and 8:00 am. RESULTS: Each subject demonstrated greater salivary estriol levels at night (10:00 pm-6:00 am) than in the daytime (8:00 am-9:00 pm, P <.001). Salivary estriol levels consistently increased at 10:00 pm, peaked at 4:00 am, and returned to daytime levels between 6:00 and 7:00 am. Salivary estriol concentrations were stable during daylight hours. CONCLUSIONS: (1) There was a dramatic diurnal variation in salivary estriol levels (nadir during daylight with nighttime apogee). (2) Diurnal patterns and salivary estriol levels were consistent in each of 14 subjects evaluated in the latter half of pregnancy. Samples for baseline measurements of salivary estriol level should be obtained during daylight hours (8:00 am-8:00 pm).

Adolescent↗
PubMed1999

Successful treatment of cerebral toxoplasmosis in a marrow transplant recipient: contribution of a PCR test in diagnosis and early detection.

We report successful treatment of cerebral toxoplasmosis in an unrelated donor marrow transplant recipient. The clinical diagnosis was confirmed by polymerase chain reaction (PCR) amplification for T. gondii-DNA performed both on cerebrospinal fluid and blood leukocytes. Retrospective testing of stored blood samples demonstrated positive leukocyte PCR signal detected up to 52 days prior to onset of clinical symptoms. This case highlights the value of PCR in the diagnosis and early detection of cerebral toxoplasmosis.

Adult↗
PubMed1999

'Hello, my name is Gabriel, I am the house officer, may I examine you?' or the Objective Santa Christmas Examination (OSCE).

OBJECTIVE: To design a clinical examination of high content validity suitable for use as a formative assessment tool with pre-registration house officers (PRHO'S) towards the end of their first house officer post. DESIGN: A multicentre collaboration between four UK medical schools who offer undergraduate curricula which are problem-based, systems-based, patient-orientated, student-centred, jargon-laden and utterly staff-bewildering. MAIN OUTCOME: An objective structured clinical examination (OSCE) which is suitable for use with graduates of UK medical schools. It assesses the knowledge, skills and attitudes essential for future careers in a hierarchical system where protecting the senior staff from all forms of irritation is paramount. RESULTS: PRHO'S who excel in this examination get better references. CONCLUSION: The OSCE format can be used to provide 'real-life' scenarios appropriate to the season.

Career Choice↗
PubMed1999

Responses of single taste fibers and whole chorda tympani and glossopharyngeal nerve in the domestic pig, Sus scrofa.

Whole nerve, as well as single fiber, responses in the chorda tympani proper (CT) and glossopharyngeal (NG) nerves of 1- to 7-week-old pigs were recorded during taste stimulation. In the CT acids and in the NG bitter compounds gave the largest responses. Both nerves exhibited large responses to monosodium glutamate (MSG), MSG with guanosine 5'-monophosphate (GMP) and MSG with inositine 5'-monophosphate (IMP) as well as to glycine, xylitol, sucrose, fructose and glucose. Alitame, aspartame, betaine, neohesperedin dihydrochalcone (NHDHC), super-aspartame, saccharin and thaumatin elicited no or little response. Hierarchical cluster analysis of 49 CT fibers separated four major clusters. The M cluster, comprising 28.5% of all fibers, is characterized by strong responses to MSG, KCl, LiCl and NaCl. The responses to NaCl and LiCl were unaffected by amiloride. The H cluster (24.5%) includes units responding principally to acids. The Q cluster (18.5%) responds to quinine hydrochloride (QHCl), sucrose octaacetate (SOA) and salts with amiloride. The S cluster (28.5%) exhibits strong responses to xylitol, glycine and the carbohydrates as well as to MSG alone and to MSG with GMP or IMP. In 31 NG fibers, hierarchical cluster analysis revealed four clusters: the M cluster (10%), responding to MSG and MSG with GMP or IMP; the H cluster (13%), responding to acids; the Q cluster (29%), responding strongly to QHCl, SOA and tilmicosinR; and the S cluster (48%), responding best to xylitol, carbohydrates and glycine but also to the umami compounds. Multidimensional scaling analysis across fiber responses to all stimuli showed the best separation between compounds with different taste qualities when information from both nerves was utilized.

Age Factors↗
PubMed1999

Carboplatin and paclitaxel, alone and in combination: dose escalation, measurement of renal function, and role of the p53 tumor suppressor gene.

In this pharmacokinetic and dose-escalation study of the carboplatin/paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) combination, patients were randomly assigned to receive paclitaxel either as a 1-hour or a 3-hour infusion. The 1-hour infusion was feasible, with maximum tolerated doses similar to those previously reported for a 3-hour infusion. Using patients' age, height, plasma creatinine, and plasma creatine kinase provided an improved estimate of the glomerular filtration rate compared with the more traditional creatinine-based formulas according to population analysis of data derived from glomerular filtration rate estimates performed by an isotope method. Studies of the p53 gene sequence of ovarian tumors at diagnosis suggest that p53 mutations are a potent predictor of response to subsequent treatment with carboplatin.

Antineoplastic Agents, Phytogenic↗