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H Richards

Publications and source records attributed to H Richards.

At least 19 recordsLinked to original sources
PubMed2005

Isolation of silver- and antibiotic-resistant Enterobacter cloacae from teeth.

Antibiotic-resistant bacteria pose a serious threat to human health; hence the mechanisms that lead to their selection need to be investigated. One possible mechanism is that the silver and mercury in amalgam dental restorations may select for bacteria that contain heavy metal and antibiotic-resistance determinants, leading to the spread of these resistances, particularly if they are contained on the same mobile genetic element. The incidence of silver-resistant bacteria on teeth is investigated in this work. Two silver-resistant Enterobacter cloacae isolates were isolated from infected teeth containing dental restorations. Both isolates were also resistant to ampicillin, erythromycin, and clindamycin. The silE gene, which is encoded on the silver resistance operon, has been sequenced from both isolates. Results suggest that the silver resistance operon is encoded on plasmid DNA.

Dental Amalgam↗
PubMed2004

Does patient controlled analgesia delay the diagnosis of compartment syndrome following intramedullary nailing of the tibia?

We report on four cases in which the diagnosis of compartment syndrome was delayed by the administration of patient controlled analgesia (PCA) following intramedullary nailing of tibial shaft fractures. We believe that this poses a diagnostic problem and can lead to lasting sequelae as decompression is delayed. We recommend extra vigilance with the use of PCA in patients with intramedullary nailing following tibial shaft fractures.

Adult↗
PubMed2002

Prevalence and antibiotic resistance profile of mercury-resistant oral bacteria from children with and without mercury amalgam fillings.

Genes encoding resistance to mercury and to antibiotics are often carried on the same mobile genetic element and so it is possible that mercury-containing dental materials may select for bacteria resistant to mercury and to antibiotics. The main aim of this study was to determine whether the prevalence of Hg-resistant oral bacteria was greater in children with mercury amalgam fillings than in those without. A secondary aim was to determine whether the Hg-resistant isolates were also antibiotic resistant. Bacteria in dental plaque and saliva from 41 children with amalgam fillings and 42 children without such fillings were screened for mercury resistance by cultivation on a HgCl(2)-containing medium. Surviving organisms were identified and their susceptibility to mercury and to several antibiotics was determined. Seventy-eight per cent and 74% of children in the amalgam group and amalgam-free group, respectively, harboured Hg-resistant bacteria; this difference was not statistically significant. Nor was there any significant difference between the groups in terms of the proportions of Hg-resistant bacteria in the oral microflora of the children. Of Hg-resistant bacteria, 88% and 92% from the amalgam group and the amalgam-free group, respectively, were streptococci; 41% and 33% were resistant to at least one antibiotic, most frequently tetracycline. The results of this study show that there was no significant difference between children with amalgam fillings and those without such fillings with regard to the prevalence, or the proportion, of Hg-resistant bacteria in their oral microflora. The study also found that Hg-resistant bacteria were common in children regardless of whether or not they had amalgam fillings and that many of these organisms were also resistant to antibiotics.

Adolescent↗
PubMed2001

Locomotion and feeding of Acanthamoeba at the water-air interface of ponds.

Acanthamoeba trophozoites attach to and effect amoeboid locomotion at the water-air interface of ponds. Their locomotory rate (approximately 0.8 microm s(-1)) and manner of independent movement at this interface is similar to that over solid substrata. Adhesion forces developed between amoebae and the water-air interface are greater than gravity and thus amoebae are also transported passively without detachment. Amoebae docked with the water-air interface remain and flourish here as they are shown, by using green fluorescent protein-labelled Aeromonas hydrophila, to feed on bacteria that occur at the interface, digesting them intracellularly.

Acanthamoeba↗
PubMed2000

The 'doctor' or the 'girl from the University'? Considering the influence of professional roles on qualitative interviewing.

BACKGROUND: Qualitative research methods are now recognized as valuable tools for primary care. With the increasing emphasis on evidence-based medicine and critical appraisal of published work, it is important that qualitative researchers are transparent about their methods and discuss the impact of the research process on their data. OBJECTIVES: To consider the impact of the professional background of researchers on in-depth interviewing in primary care. METHODS: We compare interactions between the interviewer and respondents in two qualitative interview studies of heart disease. Both samples consisted of 60 middle-aged men and women from a range of social backgrounds living in the West of Scotland. One study was conducted by a GP and the other by a sociologist. RESULTS: Some interview interactions were common to both researchers; for example, interviews were often regarded by respondents as therapeutic. However, some interactions seemed to be related to the researcher's professional background. The GP's perceived higher status led to obscuring of her personal characteristics. The sociologist was often perceived as a 'young woman' rather than defined by her professional role. Thus respondents' perceptions of the interviewer influenced the interview interactions. CONCLUSIONS: Appraising qualitative research depends on the transparency with which the research process is described. Awareness of professional background is particularly important for university departments of primary care (which often include doctors, nurses and social scientists) and should be considered carefully in designing, carrying out and disseminating the results of qualitative studies.

Adult↗
PubMed2000

Social and gender variation in the prevalence, presentation and general practitioner provisional diagnosis of chest pain.

OBJECTIVES: To describe the prevalence of Rose angina and non-exertional chest pain in men and women in socioeconomically contrasting areas; to describe the proportions of men and women who present with the symptom of chest pain and who receive a provisional general practitioner diagnosis of coronary heart disease; to assess the effects of gender and deprivation. DESIGN: Two random general population samples in socially contrasting areas were surveyed using the Rose angina questionnaire: the case notes of people identified with chest pain were reviewed. SETTING: Glasgow conurbation. PARTICIPANTS: 1107 men and women, aged 45-64, with chest pain. OUTCOME MEASURES: Prevalence of Rose angina and non-exertional chest pain; the proportions who had presented with chest pain and received a general practitioner's provisional diagnosis of coronary heart disease. RESULTS: There was no difference between social groups in the prevalence of all chest pain but a greater proportion of those in deprived groups had Rose angina and a greater proportion of these had the more severe grade. The proportion of people who had presented with chest pain was higher among socioeconomically deprived groups but there was no difference in the proportions receiving a general practitioner provisional diagnosis of coronary heart disease. Men were more likely to present with chest pain than women and were more likely to receive a provisional general practitioner diagnosis of coronary heart disease. CONCLUSIONS: No evidence was found of social differences in patient presentation or general practitioner diagnosis that might explain reported variations in uptake of cardiology services. In contrast, gender variation may originate in part from differences in patient presentation and general practitioner diagnosis. Further investigation of socioeconomic variations in uptake of cardiology services should focus later in the care pathway, on general practitioner referral patterns and clinical decisions taken in secondary care.

Age Distribution↗
PubMed2000

The Development and Well-Being Assessment: description and initial validation of an integrated assessment of child and adolescent psychopathology.

The Development and Well-Being Assessment (DAWBA) is a novel package of questionnaires, interviews, and rating techniques designed to generate ICD-10 and DSM-IV psychiatric diagnoses on 5-16-year-olds. Nonclinical interviewers administer a structured interview to parents about psychiatric symptoms and resultant impact. When definite symptoms are identified by the structured questions, interviewers use open-ended questions and supplementary prompts to get parents to describe the problems in their own words. These descriptions are transcribed verbatim by the interviewers but are not rated by them. A similar interview is administered to 11-16-year-olds. Teachers complete a brief questionnaire covering the main conduct, emotional, and hyperactivity symptoms and any resultant impairment. The different sorts of information are brought together by a computer program that also predicts likely diagnoses. These computer-generated summary sheets and diagnoses form a convenient starting point for experienced clinical raters, who decide whether to accept or overturn the computer diagnosis (or lack of diagnosis) in the light of their review of all the data, including transcripts. In the present study, the DAWBA was administered to community (N = 491) and clinic (N = 39) samples. There was excellent discrimination between community and clinic samples in rates of diagnosed disorder. Within the community sample, subjects with and without diagnosed disorders differed markedly in external characteristics and prognosis. In the clinic sample, there was substantial agreement between DAWBA and case note diagnoses, though the DAWBA diagnosed more comorbid disorders. The use of screening questions and skip rules greatly reduced interview length by allowing many sections to be omitted with very little loss of positive information. Overall, the DAWBA successfully combined the cheapness and simplicity of respondent-based measures with the clinical persuasiveness of investigator-based diagnoses. The DAWBA has considerable potential as an epidemiological measure, and may prove to be of clinical value too.

Adolescent↗
PubMed1999

Anger as a predictor of aggression among incarcerated adolescents.

This study examined the validity of trait anger as a predictor of aggressive behavior among juvenile offenders. Two standard self-report anger scales were administered to 65 recently incarcerated male adolescents. These youths were followed prospectively for physical and verbal aggression during 3 months of subsequent incarceration. Anger scores were not correlated with participant history of violent offending or staff ratings of anger. However, anger scores from both instruments were predictive of subsequent physical and verbal aggression. For example, the Trait Anger scale successfully classified 66% of juvenile offenders into high and low aggressive groups; receiver operating characteristic analysis obtained an effect size of .72. These results support the predictive validity of self-reported anger in identifying juvenile offenders at risk for institutional aggression.

Adolescent↗
PubMed1999

Influence of twenty-five per cent human serum albumin on total and ionized calcium concentrations in vivo.

BACKGROUND: A inverse correlation has been found between changes in ionized calcium concentrations and the addition of albumin in vitro, which may explain adverse cardiovascular effects attributed to exogenous albumin in vivo. The purpose of this investigation was to determine the interaction (if any) between exogenous 25% albumin administration (100 ml given over < 30 min) and calcium concentrations in patients, all but one of whom were in an intensive care unit. RESULTS: There were no significant differences in the ionized calcium concentrations obtained before, at the end and 6 h after the administration of albumin (1.09 +/- 0.23, 1.06 +/- 0.22, 1.06 +/- 0.21 mmol/l, respectively). Similarly, there were no significant differences in the total calcium concentrations between these same time periods (2.03 +/- 0.18, 2.05 +/- 0.20, 2.08 +/- 0.23 mmol/l, respectively). CONCLUSIONS: In patients receiving infusions of 25% albumin, it appears that circulating calcium concentrations are well regulated by homeostatic mechanisms. Albumin infusions had no effect on calcium concentrations, although it is possible that temporary changes of questionable clinical importance may have occurred between measurement periods.

Journal Article↗
PubMed1998

Hydrodynamic properties of hydrocephalus shunts.

Hydrodynamic properties of hydrocephalus shunts are not always properly characterized by the manufacturer. Therefore, the choice of the shunt should be made, by matching performance of the shunt to the disturbed profile of CSF circulation of a given patient. The aim of the present shunt evaluation study is to evaluates all types of shunts presently in use in the U.K. and make this information available to neurosurgeons. Ten most common models of valves have been tested to date: Medtronik PS Medical: Delta Valve, Flow Control Valves and Lumbo-Peritoneal Shunt, Heyer-Schulte: In-line, Low Profile and Pudenz Flushing Valve, Codman: Medos-Programmable, Hakim-Precision, Sophy Programmable Valve, Cordis Orbis-Sigma. Our results show the majority of valves have low hydrodynamic resistance (exception: PS Lumboperitoneal, Orbis-Sigma), which increase by 100-200% after connection of a long distal catheter. A few shunts with siphon-preventing mechanism (Delta, Hayer-Schulte Low Profile, Pudenz-Flushing) offer reasonable resistance to negative outlet pressures, however, these valves may be blocked by raised subcutaneous pressure. All programmable valves are susceptible to siphoning. Programmed settings may be changed by external magnetic field.

Cerebrospinal Fluid Pressure↗
PubMed1997

A computing system for the clinical and experimental investigation of cerebrovascular reactivity.

We present a computing system for the recording and on-line analysis of analogue signals derived from bedside cerebrovascular monitors in different pathophysiological conditions. These include arterial blood pressure and oxygen saturation, end-tidal carbon dioxide concentration, cerebral blood flow velocities using transcranial Doppler ultrasonography, and concentration changes in cerebral oxy- and deoxyhaemoglobin from near infrared spectroscopy. Configuration and analysis adopts arithmetic expressions of different signal processing functions, various statistical properties for each signal, frequency spectrum analysis using fast Fourier transformation, and correlation/cross-correlation. The software offers off-line analysis of non-invasive tests of cerebrovascular reactivity. Several examples of clinical assessment of cerebrovascular reactivity are presented, including cerebral haemodynamic stress tests which employ carbon dioxide, acetazolamide, the breath holding test, leg cuff inflation and deflation, and transient carotid artery compression. Application within the experimental setting with induced haemorrhagic hypotension can also be used.

Cardiovascular Diseases↗
PubMed1996

A feedback-controlled pump produces stable hypotension in anaesthetised rabbits.

A method is described for the reliable production of controlled hypotension in experimental animals. Reduction in arterial blood pressure was obtained in rabbits by withdrawing arterial blood using a computer-driven pump operating within a feedback control system. Arterial blood pressure, blood flow velocity in the basilar artery (measured using transcranial Doppler), and anterior cortical microcirculation (measured using laser Doppler) were monitored. The aim of the experiments was to compare stability of hypotension produced using arterial blood pressure or basilar flow velocity as feedback control variables. Basilar artery flow velocity provided the most stable profound hypotension and during reinfusion when animals were not autoregulating. However, arterial blood pressure provided the most accurate stepwise control in autoregulating animals.

Anesthesia↗
PubMed1996

Rating child psychiatric caseness from detailed case histories.

Novel operationalized criteria were used to rate detailed psychiatric case histories on 151 schoolchildren with hemiplegia. Ratings of psychiatric caseness or non-caseness were reliable and valid; the method may be widely applicable. Caseness was defined both narrowly (in terms of social incapacity for the child) and broadly (in terms of disruption to others and distress too). Both definitions could be applied reliably to children of normal intelligence but broadly defined caseness was more reliable for children with low intelligence. Barely half of the psychiatric cases met operationalized criteria for one or more DSM-IV or ICD-10 diagnosis. The others mostly had partial or mixed syndromes that could, with clinical judgement, be assigned to "not otherwise specified' diagnoses. Even with clinical judgement, however, a substantial minority of children with low intelligence had clinically significant but undiagnosable abnormalities in social relatedness.

Affective Symptoms↗
PubMed1996

Are only children different? A study of child psychiatric referrals. A research note.

For this study, 683 only children seen in a psychiatric clinic were compared with 2364 children from two-child families seen in the same clinic. From the age of 5 years, there were no differences between the two groups. Among the under-5s, a higher proportion of only children had problems which did not warrant a psychiatric diagnosis, and their parents were more often rated as being over-protective. Our findings suggest, however, that the parents of only children differ from other parents not in being more over-protective but in being more willing or able to seek medical advice.

Adolescent↗