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Biomedical subjects

S Crawford

Publications and source records attributed to S Crawford.

At least 55 records · Page 3Linked to original sources
PubMed1998

Lymph node human immunodeficiency virus RNA levels and resistance mutations in patients receiving high-dose saquinavir.

The development of resistance mutations and human immunodeficiency virus (HIV) RNA levels were compared in lymph nodes and plasma of patients receiving antiretroviral therapy. Ten HIV-positive patients receiving high-dose saquinavir monotherapy (3600 or 7200 mg/day) underwent 14 lymph node biopsies before and during therapy. HIV RNA levels and appearance of resistance mutations to saquinavir were determined in simultaneous lymph node and plasma samples. HIV RNA levels were found to be consistently higher (mean, 3.16 log RNA copies; SD, 1.04; range, 2.23-5.59) in lymph nodes than in simultaneous plasma samples. Saquinavir therapy resulted in a reduction in HIV RNA levels in both plasma and lymph nodes. The presence or absence of a resistance mutation to saquinavir at codons 48 or 90 of the HIV-1 protease gene was identical in 13 of 14 biopsies, suggesting that resistance mutations to saquinavir appear within close temporal proximity in lymph nodes and plasma.

Anti-HIV Agents↗
PubMed1998

Interrelationships among disablement concepts.

BACKGROUND: Understanding interrelationships among disablement concepts is critical to the design of future disability treatment and prevention interventions. METHODS: This study uses cross-sectional data to examine the relationships among physiologic impairments, functional limitations, and disability in a moderately disabled sample of 207 community-dwelling older adults. RESULTS: As hypothesized, the data revealed statistically significant curvilinear relationships of upper and lower extremity strength and balance with mobility in this older sample. Multivariate analyses further clarified the hypothesized causal mechanism among the disablement concepts by demonstrating that most of the association of muscle strength and balance with disability was through the intermediary role of mobility limitations. CONCLUSIONS: The findings from this study highlight the value of clinical trials that focus on prevention or treatment of mobility limitations as a means of preventing disability; our findings underscore the need for future research that examines the effects of other variables believed to influence disablement in late life.

Aged↗
PubMed1998

Routine follow up after head injury: a second randomised controlled trial.

OBJECTIVE: To confirm that patients admitted to hospital with a head injury benefit from a routinely offered early intervention service. PATIENTS AND METHODS: A mixed rural and urban Health District of 560000 people with two accident and emergency departments provided the setting. Existing routine services for most patients with head injury are minimal. All patients aged 16-65 years admitted to hospital after a head injury of any severity, with or without other injuries entered the trial. Prospective randomisation, with a block randomisation procedure was used to allocate all eligible patients to either: a group offered an additional service by a specialist team; or a group receiving existing standard services. Patients were assessed at follow up six months after injury. The primary outcome measure was the Rivermead head injury follow up questionnaire, a validated and reliable measure of social disability. The Rivermead post-concussion symptoms questionnaire was used to estimate severity of post-concussion symptoms. Each patient in the trial group was contacted 7-10 days after injury, and offered assessment and interventions as needed. These initially focused on the provision of information, support, and advice. Forty six per cent of patients in the trial group also received further outpatient intervention or additional support by telephone. RESULTS: 314 patients were registered: 184 were randomised into the trial group, 130 into the control group. For prognostic data, the groups were comparable at randomisation, and remained comparable when assessed at six months. 132 trial and 86 control patients were followed up at six months after injury. Patients' posttraumatic amnesia ranged from mild (n=79, 40%), and moderate (n=62, 32%), to severe (n=38, 19%) and very severe (n=17, 9%). The trial group patients had significantly less social disability (p=0.01) and significantly less severe post-concussion symptoms (p=0.02) at follow up at six months after injury than the control group patients. CONCLUSIONS: The early interventions offered by a specialist service significantly reduced social morbidity and severity of post-concussion symptoms in trial group patients at six months after head injury. Recommendations about how specialist services should be targeted are made both in the light of these results and those from a previous randomised controlled trial.

Adolescent↗
PubMed1998

Assault, post-traumatic amnesia and other variables related to outcome following head injury.

OBJECTIVE: To estimate how many patients who sustain a head injury might benefit from intervention and support each year and to consider whether relationships can be found between demographic data relating to patients' circumstances at the time of head injury, and their outcomes six months later. DESIGN: Data collected on 625 patients through follow-up interviews and assessments by the Oxford Head Injury Service for a randomized controlled trial of intervention conducted in 1993-94. SETTING: A mixed rural and urban Health District with a population of approximately 560,000. PATIENTS: Patients were aged between 16 and 65 years and resident in Oxfordshire. They presented over 13 months to accident and emergency departments, or were admitted to hospital. All were diagnosed as having suffered a head injury. OUTCOME MEASURES: The Rivermead Head Injury Follow Up Questionnaire and the Rivermead Post Concussion Symptoms Questionnaire. RESULTS: Data are given on age, sex, social circumstances, employment, cause of injury, severity of associated injuries, post-traumatic amnesia (PTA), anticonvulsants, postconcussion symptoms and activities of everyday life. Outcome at six months was significantly worse for those who had been assaulted as against all other causes of injury combined (p = 0.0001); and/or had been admitted to hospital (p = 0.0001)l and/or had sustained more severe additional injuries (p = 0.04); and/or had experienced any PTA (p = 0.00001). The minimum incidence of such injuries in those aged 16-65, calculated for Oxfordshire, is 292 per annum (74/100,000 aged 16-65 per year). CONCLUSIONS: In the general population 52/100,000 patients per annum will experience more serious head injuries as indicated by hospital admission and/or one or more fractures and/or any length of PTA and/or having been assaulted. This group may benefit from monitoring and support and their needs should be considered when planning services.

Accidents↗
PubMed1997

The effects of health care reforms on job satisfaction and voluntary turnover among hospital-based nurses.

OBJECTIVES: Among the consequences of downsizing and cost containment in hospitals are major changes in the work life of nurses. As hospitals become smaller, patient acuity rises, and the job of nursing becomes more technical and difficult. This article examines the effects of changes in the hospital environment on nurses' job satisfaction and voluntary turnover between 1993 and 1994. METHODS: Data were collected in a longitudinal survey of 736 hospital nurses in one hospital to examine correlates of change in aspects of job satisfaction and predictors of leaving among nurses who terminated in that period. RESULTS: Unadjusted results showed decline in most aspects of satisfaction as measured by Hinshaw and Atwood's and Price and Mueller's scales. Multivariate analysis indicated that the most important determinants of low satisfaction were poor instrumental communication within the organization and too great a workload. Intent to leave was predicted by the perception of little promotional opportunity, high routinization, low decision latitude, and poor communication. Predictors of turnover were fewer years on the job, expressed intent to leave, and not enough time to do the job well. CONCLUSIONS: The authors conclude that although many aspects of job satisfaction are diminished, some factors predicting low satisfaction and turnover may be amenable to change by hospital administrators.

Adult↗
PubMed1997

Measurement of post-traumatic amnesia: how reliable is it?

OBJECTIVE: To develop and test a clinical protocol for determining post-traumatic amnesia by retrospective questioning. To establish its limits and factors which influence reliability. DESIGN: Two independent assessments using the Rivermead post-traumatic amnesia protocol were undertaken by separate observers on various groups of patients at various time intervals. Analysis investigated the correlations between assessments, the percentage difference between assessments, the number of patients changing category, and the differences between these analyses in the different patient subgroups. Assessments were undertaken both in hospital and in the patients' homes. Four different patient groups were studied. These were group A: 12 inpatients with very severe head injury late after injury; Group B: 40 patients interviewed at home six months after injury; group C: 22 patients interviewed within a few weeks of injury at home; group D: 116 patients interviewed initially within a few weeks and then at six months, on both occasions at home. The Rivermead post-traumatic amnesia protocol involved clinical questioning of the patient to establish how long after injury (in hours/days/weeks) the patient regained continuous day to day memory. All periods of coma were included. Severity was categorised with standard criteria. RESULTS: Overall correlation was good (Spearman's r 0.79), but the correlation was lower for patients with post-traumatic amnesia < 24 hours and when there was a long delay between assessments. In all groups 19%-25% of patients changed categories between assessments, but only 2% changed by two categories. CONCLUSIONS: The assessment of post-traumatic amnesia with the Rivermead post-traumatic amnesia protocol is reasonably reliable. The misclassification rate however, is significant enough that some caution should be taken in individual cases. Other evidence does show post-traumatic amnesia to be valid, and it probably remains the best simple prognostic item available. In clinical practice one should avoid placing too much weight on post-traumatic amnesia alone.

Adult↗
PubMed1997

Does routine follow up after head injury help? A randomised controlled trial.

OBJECTIVE: To evaluate the Medical Disability Society's 1988 recommendation that "every patient attending hospital after a head injury should be registered and offered an outpatient follow up appointment" by determining whether offering a routine follow up service to patients presenting to hospital with a head injury of any severity affects outcome six months later. DESIGN: A randomised controlled trial design with masked assessment of outcome. SETTING: A mixed rural and urban health district with a population of about 560000. PATIENTS: 1156 consecutive patients resident in Oxfordshire aged between 16 and 65 years presenting over 13 months to accident and emergency departments or admitted to hospital and diagnosed as having a head injury of any severity, including those with other injuries. INTERVENTIONS: Patients were registered and randomised to one of two groups. Both groups continued to receive the standard service offered by the hospitals. The early follow up group were approached at 7-10 days after injury and offered additional information, advice, support, and further intervention as needed. All randomised patients were approached for follow up assessment six months after injury by independent clinicians blind to their group. MAIN OUTCOME MEASURES: Validated questionnaires were used to elicit ratings of post-concussion symptoms (the Rivermead postconcussion symptoms questionnaire), and changes in work, relationships, leisure, social, and domestic activities (the Rivermead head injury follow up questionnaire). RESULTS: The two groups were comparable at randomisation. Data was obtained at six months on 226 of 577 "control" patients and 252 of 579 "trial" patients (59% were lost to follow up). There were no significant differences overall between the trial and control groups at follow up, but subgroup analysis of the patients with moderate or severe head injuries (posttraumatic amnesia > or = one hour, or admitted to hospital), showed that those in the early intervention group had significantly fewer difficulties with everyday activities (P = 0.03). CONCLUSIONS: The results from the 41% of patients followed up do not support the recommendation of offering a routine follow up to all patients with head injury, but they do suggest that routine follow up is most likely to be beneficial to patients with moderate or severe head injuries. Some of those with less severe injuries do continue to experience difficulties and need access to services. A further trial is under way to test these conclusions.

Adaptation, Psychological↗
PubMed1997

Interventions and service need following mild and moderate head injury: the Oxford Head Injury Service.

OBJECTIVE: To describe the interventions given by the Oxford Head Injury Service (OXHIS) to patients seen after head injury, predominantly mild or moderate, over the first six months after their injuries. DESIGN: Descriptive data of the amounts of early intervention provided by OXHIS in relation to severity of head injury and the amount of service need identified at six month follow-up. SETTING: OXHIS aimed to register all patients aged 16-65 with a head injury of any severity, resident in Oxfordshire. It contacted and provided interventions for a random half of those registered at 7-10 days post-injury as part of a randomized controlled trial to investigate the effectiveness of early follow-up. At six months post-injury, independent assessment of all those registered was undertaken to evaluate outcome and identify continuing service needs. SUBJECTS: The data come from the 579 patients (of the 1156 registered), randomized to receive the new service at 7-10 days post-injury. All but eight of these received some form of service, and 252 of the randomized patients were available for interview at six months post-injury to assess their continuing service need. RESULTS: In the first five months after head injury: 240 patients received postal information alone and were not otherwise in contact with the service; 127 had telephone contact, advice and information; 93 were seen in person, assessed and given advice and information; 78 needed more help and support from the OXHIS team over the telephone; and 33 required further face-to-face contact either from OXHIS or other services. Extensive use was made of standardized leaflets but only accompanied by individualized assessment and advice. At six months 252 of the 579 patients were interviewed: 101 had no problems; 136 needed further reassurance; and 15 required further intervention. Patients with longer periods of post-traumatic amnesia (PTA) were more likely to receive a higher level of service, but the majority of patients who received the more extensive services were those with 'mild' and 'moderate' head injuries. CONCLUSIONS: Although the amount of service provided at 7-10 days post-injury increased with severity of head injury, most service was in fact given to patients with milder head injuries which were much more common. The majority of patients seen at six months post-injury needed reassurance, advice or other services, and monitoring of patients for some time after their head injuries does seem warranted. A population of 560,000 people could receive service from three whole-time equivalent (WTE) staff using these assessment and management protocols.

Adolescent↗
PubMed1996

Virus-like particles as a rotavirus subunit vaccine.

Rotavirus subunit vaccines are being evaluated for use in humans. The virus-like particles (VLPs) for these vaccines are produced in insect cells coinfected with combinations of baculovirus recombinants expressing bovine RIF VP2 and simian SA11, VP4, VP6, or VP7 rotavirus proteins. VLPs were administered parenterally to mice and rabbits, and the immunogenicity and protective efficacy of the vaccines were evaluated. Rabbits vaccinated with VP2/4/6/7 or VP2/6/7 VLP combinations developed high levels of rotavirus-specific serum antibody and fecal IgG but not fecal IgA. The induction of fecal IgG was associated with total or partial protection from oral challenge with ALA rotavirus. Heterotypic serum and fecal neutralizing antibody was induced in mice vaccinated parenterally with G1 VP2/6/7 or VP2/4/6n VLPs. VLPs were highly immunogenic when administered in QS21 adjuvant, inducing serum neutralizing antibody titers comparable to those induced by SA11 virus. VLPs are effective immunogens when administered parenterally and may be an effective subunit vaccine.

Animals↗
PubMed1996

The Rivermead head injury follow up questionnaire: a study of a new rating scale and other measures to evaluate outcome after head injury.

OBJECTIVE: To develop and evaluate a short (10 item) simple measure of outcome mainly for use with patients with mild to moderate head injuries. DESIGN: Two studies on patients at three and six months after injury, comparing different methods of administration (two raters and postal questionnaire), and comparing ratings with other assessments. SUBJECTS: Forty three patients seen three months after injury and 46 seen six months after injury; both groups had head injuries covering a range of severity from minor to severe. MAIN OUTCOME MEASURES: Differences between ratings in different groups of patients (Mann-Whitney U test); differences in ratings used different methods of administration (Wilcoxon signed rank test); and correlation between ratings from the same patient (Spearman r). RESULTS: The sum total ratings were consistent between raters and between methods (postal questionnaire v face to face interview) with no evidence of selective bias between rates or methods. Ratings on individual items were also reasonably consistent. The sum total rating varied as anticipated between groups divided by clinical judgement of recovery and patient assessment of recovery, and related as expected to the extent of post-concussion symptomatology. The 10 items included covered the most important problem areas reported by patients. CONCLUSION: The Rivermead head injury follow up questionnaire (RHFUQ) is a short, simple, adequately reliable, and valid measure of outcome, across the entire range of severity, but particularly after mild to moderate head injury.

Adolescent↗
PubMed1996

The relationship between hepatic copper content and morphologic changes in the liver of West Highland White Terriers.

Liver tissue from 17 West Highland White Terriers (WHWTs) with cirrhosis, subacute bridging necrosis, hepatitis, or massive necrosis were examined for the presence, composition, and distribution of inflammatory foci. Copper analysis was performed on the specimens. The foci of inflammation and necrosis composed a significant part of the lesion in 15 of the samples. The foci were of two types. One, characteristic of idiopathic chronic active hepatitis, consisted of one or two apoptotic hepatocytes attended by lymphocytes and plasma cells. These foci were found primarily in the vicinity of the portal tracts, not associated with centrolobular copper-laden hepatocytes. The other type of focus was characteristic of copper toxicosis. These foci were larger and composed of debris-filled macrophages, lymphocytes, plasma cells, and scattered neutrophils, and on occasion apoptotic hepatocytes were found at the periphery. These foci were always found around the central vein among the copper-laden hepatocytes. Such foci were found only in dogs with copper concentration > 2,000 parts/million on a dry weight basis. These morphologic studies show that clinical liver disease in WHWTs is caused by more than one etiologic agent. Among 17 WHWTs with clinical liver disease, two had copper toxicosis, five had idiopathic chronic active hepatitis, and 10 had hepatic disease of undetermined type.

Animals↗
PubMed1996

Informal care vs. formal services: changes in patterns of care over time.

Longitudinal data from a representative sample of community-residing older persons were used to document changes in patterns and costs of care, both informal and formal. It was found that use of formal services was usually in conjunction with, and secondary to, informal care. Limited availability of informal care as well as increased disability raised the odds of using services. Substitution of formal services for informal care was limited and usually temporary. Total costs of community care, including living expenses, were generally less than the cost of nursing home care.

Activities of Daily Living↗
PubMed1995

The Rivermead Post Concussion Symptoms Questionnaire: a measure of symptoms commonly experienced after head injury and its reliability.

After head injuries, particularly mild or moderate ones, a range of post-concussion symptoms (PCS) are often reported by patients. Such symptoms may significantly affect patients' psychosocial functioning. To date, no measure of the severity of PCS has been developed. This study presents the Rivermead Post Concussion Symptoms Questionnaire (RPQ) as such a measure, derived from published material, and investigates its reliability. The RPQ's reliability was investigated under two experimental conditions. Study 1 examined its test-retest reliability when used as a self-report questionnaire at 7-10 days after injury. Forty-one head-injured patients completed an RPQ at 7-10 days following their head injury and again approximately 24 h later. Study 2 examined the questionnaire's inter-rater reliability when used as a measure administered by two separate investigators. Forty-six head-injured patients had an RPQ administered by an investigator at 6 months after injury. A second investigator readministered the questionnaire approximately 7 days later. Spearman rank correlation coefficients were calculated for ratings on the total symptom scores, and for individual items. High reliability was found for the total PCS scores under both experimental conditions (Rs = + 0.91 in study 1 and Rs = + 0.87 in study 2). Good reliability was also found for individual PCS items generally, although with some variation between different symptoms. The results are discussed in relation to the major difficulties involved when looking for appropriate experimental criteria against which measures of PCS can be validated.

Adolescent↗
PubMed1995

How does formal and informal community care affect nursing home use?

We examined the effects of informal and formal community care on the 6-year risk of nursing home use in a representative sample of disabled elders. Increased risk was associated with receiving formal community services and with caregiver burnout. There was a modest reduction in risk of using a nursing home among those receiving greater amounts of informal care. Elders with male caregivers were at over twice the risk of using a nursing home than those with female caregivers, while those who lived with their primary caregiver were at reduced risk. Increasing amount of formal services was associated with reduced risk of nursing home use for cognitively impaired older persons. Formal community services did not buffer the effects of severity of disability on nursing home use. Supplementing informal services with formal care was associated with greater risk of using a nursing home. Future research should move beyond testing global hypotheses regarding the protective effects of informal and formal community care and examine the impact of specific types of community care for specific subgroups of older persons on subsequent nursing home use.

Aged↗
PubMed1995

Detection of mycobacteria in bone marrow biopsy specimens taken to investigate pyrexia of unknown origin.

AIMS: To investigate the value of bone marrow biopsy in the diagnosis of mycobacterial infection. METHODS: The culture results of 433 bone marrow samples taken between 1983 and 1992 were reviewed. The histopathology reports on bone marrow trephine specimens of culture positive samples and all those on HIV positive patients sent in 1992 were also reviewed. RESULTS: Fifty one specimens yielded Mycobacterium spp, 47 were obtained from HIV positive patients. Of the isolates, 42 were Mycobacterium avium-intracellulare (MAI), five were M tuberculosis (MTB), and the remaining four comprised a variety of atypical mycobacteria. All MAI positive samples were obtained from HIV positive patients, with the bone marrow being the only culture positive specimen in one third. Bone marrow yielded MTB only in patients from whom it was also isolated in other specimens. Eleven of 47 trephine specimens from positive bone marrow showed granulomata and nine showed acid-fast bacilli. No acid-fast bacilli were seen in the absence of granulomata. CONCLUSION: Bone marrow biopsy for mycobacterial culture should be reserved for severely immunosuppressed patients and should not be advocated for immunocompetent patients with suspected tuberculosis. Bone marrow biopsy still has a role in the investigation of pyrexia of unknown origin in HIV positive patients, despite the advent of mycobacterial blood culture techniques, particularly if these can be processed safely in automated systems.

Bone Marrow↗