Biomedical subjects

J Bell

Publications and source records attributed to J Bell.

At least 37 records · Page 2Linked to original sources

PubMed2003

Sonographic appearances of medial retinacular complex injury in transient patellar dislocation.

AIM: To describe the sonographic appearances of the medial retinacular (MPFR) complex of the knee in patients with acute and recurrent patellar dislocation. MATERIALS AND METHODS: Thirty patients were scanned within 2-4 weeks of an acute episode of lateral patellar dislocation. Eleven gave a history of recurrent patellar dislocation. Ten patients had examination under anaesthesia with arthroscopy and repair of the injury. The sonographic and operative results were compared. RESULTS: The normal sonographic appearance of the MPFR is described. Of the 10 patients who underwent examination under anaesthesia, four patients had complete avulsion of the MPFR from the patella, two patients had avulsion of the MPFR from the adductor tubercle and four patients had avulsion of the MPFR from both the patella and adductor tubercle. There was complete correlation between the sonographic and operative findings for injuries of the MPFR. Other findings included partial retinacular tears, injury to the medial collateral ligament, haematoma within vastus medialis obliquus (VMO) and bony avulsions from the patella and adductor tubercle CONCLUSION: Sonography gives reliable information regarding the site of the injury and its extent thus helping to decide whether conservative or operative treatment is the most appropriate approach to management of the injury.

Acute Disease↗

PubMed2003

Acute lateral dislocation of the patella: correlation of ultrasound scanning with operative findings.

Acute lateral dislocation of the patella has been associated with disruption of the medial restraints of the patella. Following non-operative management there is a re-dislocation rate of up to 44%. The purpose of this study was to test whether sonography is a reliable method of assessing the medial retinaculum after acute dislocation of the patella. Ten patients following acute patellar dislocation had an ultrasound scan (USS) performed by an experienced musculoskeletal radiologist. Each patient subsequently had an examination under anaesthetic, arthroscopy, and repair of the ruptured structures. The ultrasound reports were compared to the surgical findings to determine the accuracy of this investigation. USS located deficiencies in the ligamentous attachments to the medial border of the patella and the presence of avulsed bony fragments, all of which were confirmed at operation. The sonographic diagnosis of haematoma or torn fibres in the vastus medialis obliquus (VMO) corresponded with our operative findings. The most significant findings were the correlation of free fluid around the medial collateral ligament (MCL) with avulsion of the femoral attachment of the medial patellofemoral ligament (MPFL) and the presence of avulsed fragments of bone from the medial border of the patella.

Adolescent↗

PubMed2003

Squamous cell carcinoma of the oral cavity in patients aged 45 years and under: a descriptive analysis of 116 cases diagnosed in the South East of England from 1990 to 1997.

BACKGROUND: there is, currently, much anecdotal and some epidemiological evidence for a rise in oral cancer rates amongst younger individuals, many of whom have had no exposure to traditional risk factors such as tobacco and heavy alcohol use, or at least not the exposure over decades usually associated with this disease. The probity of this assertion and the presence or absence of traditional risk factors needs further evidence. OBJECTIVES: this paper describes the demography and the exposure to potential risk factors amongst a cohort aged 45 years and younger, diagnosed with squamous cell carcinoma of the oral cavity between 1990 and 1997 from the South East of England. MATERIALS AND METHODS: eligible patients registered with a cancer registry were included in this retrospective study. Information was accessed from the database and by a postal questionnaire survey. The self-completed questionnaire contained items about exposure to the following risk factors: tobacco; alcohol; diet; frequency of dental visits and familial cancer. RESULTS AND CONCLUSIONS: this is the largest UK epidemiological study so far to be undertaken on young subjects diagnosed with oral cancer. One-hundred and sixteen cases were recruited representing a response rate of 59%. Slightly over 90% of this cohort were classified as white European. A large proportion of cases (40%) were from social classes I & II suggesting either a true social class difference in young cases versus older oral cancer cases or a possible bias in responders or survivors. Risk factors of tobacco use and excessive alcohol consumption were present in the majority (75%) of patients. Significant differences in the pattern of alcohol consumption were found in female subjects, who were less likely to consume over the recommended amounts of alcohol compared with male subjects. Daily regular fresh fruit and vegetable consumption during the ten year period before cancer diagnosis was recorded to be low. There was a distinct subgroup of cases, 26% of the group, that showed little, if any, exposure to any major risk factors.

Adult↗

PubMed2003

Personality and symptom sensitivity predictors of alprazolam withdrawal in panic disorder.

BACKGROUND: Discontinuation of benzodiazepine (BZ) treatment results in a well-characterized withdrawal syndrome in 40-50% of anxious patients. While numerous studies have established the role of BZ dose, treatment duration, half-life, potency, rate of withdrawal and severity of underling anxiety disorder in predicting severity of withdrawal symptoms, fewer studies have examined the role of psychological and personality factors. METHOD: In 123 panic disorder patients undergoing gradual tapered discontinuation of alprazolam in conjunction with pre-treatment with carbamazepine or placebo, the relationship between measures of 'symptom sensitivity' and 'harm avoidance', and severity of withdrawal symptoms measured as peak severity of symptoms, time before taper needed to be slowed due to symptoms, and ability to complete taper, was examined. RESULTS: After controlling for the less substantial effects of dose, treatment duration, pre-taper anxiety and panic attack frequency, measures of symptom sensitivity and harm avoidance accounted for an additional 3-6% of withdrawal variance. CONCLUSIONS: These results show an effect of symptom sensitivity and harm avoidance on BZ withdrawal symptoms, comparable to prior findings linking dependent personality characteristics to withdrawal severity. Failure to show the expected effect on ability to complete taper may be due to either the more symptomatic nature of the patients in this study.

Adult↗

PubMed2003

Predicting the risk of cobalt deprivation in grazing livestock from soil composition data.

The objective was to derive predictive equations for acetic acid-extractable cobalt (A-ECo) in soils so that extensive national databases for total (T) Co in soils and stream sediments could be converted to 'plant available' concentrations for the purpose of predicting risk of Co deficiency in grazing livestock. Data on the chemical and physical properties of 103 soils from 15 different parent materials and 54 soil series in England and Wales were used. Ranges for the mean values for parent materials were: TCo, 5.0-20.4 and A-ECo, 0.20-1.30 mg kg-1; percentage (P) A-ECo, 3.4-13.5; soil manganese (Mn) 268-1174 mg kgDM-1; pH, 3.7-8.0. There were significant effects of parent material on all parameters with Chalks, Old and New Red Sandstones particularly low in A-ECo. Multiple linear regression yielded the following equation for predicting A-ECo, which accounted for 56% of the variance with 12 outliers, including the lowest pH values, omitted: [figure: see text] REML was used on the complete, unbalanced, log-transformed data set to fit a Generalised Mixed Model with parent material as random effect and soil Mn and pH as fixed effects; the effect of parent material was no longer significant. It was concluded that A-ECo can be satisfactorily predicted for most soils in England and Wales from TCo, TMn and soil pH.

Animal Feed↗

PubMed2002

Work stress: an exploratory study of the practices and perceptions of female junior healthcare managers.

AIM: This exploratory study set out to investigate the perceptions and practices of junior healthcare managers with regard to stress at work. BACKGROUND: It has been suggested that cultural change is needed to accommodate a shift towards recognition of organizational responsibility for stress (Schulz et al. 1985). Logically, it can be argued that junior healthcare managers, as potential future senior managers, are best placed to facilitate this change. Junior healthcare managers' current thinking about stress had not yet been explored in depth. METHOD: A combination of critical incident diaries and semistructured interviews was conducted with six junior healthcare managers. The data were analysed and transcribed using a grounded theory approach. FINDINGS: The main themes to emerge were that junior healthcare managers were generally unaware of (a) potential work stressors and (b) the effect of work stressors on their own health and performance and that of their staff. CONCLUSIONS: The perceptions and practices of junior healthcare managers suggest that there is a culture of acceptance and expectation of work stress, combined with a lack of awareness to effectively and proactively manage it.

Female↗

PubMed2002

Bypass or angioplasty for severe limb ischaemia? A Delphi Consensus Study.

OBJECTIVES: To examine the level of agreement among vascular surgeons and interventional radiologists regarding their preference for the surgical or endovascular management of severe limb ischaemia. DESIGN: Delphi consensus study using 596 different hypothetical patient scenarios. PARTICIPANTS: Delphi consensus group for the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial. METHODS: Twenty consultant vascular surgeons and 17 interventional radiologists completed both rounds of the study. The scenarios detailed the anatomical extent of disease, whether the patients had rest pain only or had tissue loss, and whether or not a suitable vein for bypass was available. Panellists were asked to score their treatment preference for either surgery or angioplasty on an eight-point scale. Outliers (top 10% and bottom 10% responses) were removed. If the remaining 80% of responses fell within a 3-point range, this was defined as "agreement". If they did not, this was considered "disagreement". RESULTS: There was substantial disagreement in 484 (81%) of scenarios in round 1 and 401 (67%) in round 2. This disagreement was greater among surgeon than radiologists in both round 1 (83 vs 65%) and round 2 (69 vs 42%). Surgeons also demonstrated less convergence between rounds. CONCLUSIONS: There is substantial disagreement between and among surgeons and radiologists with regard to the appropriateness of surgery or angioplasty for severe limb ischaemia. This lack of consensus stems from the absence of an evidence base and means that the same patient may receive entirely different treatment depending on which hospital and consultant they attend. Not only may this unexplained variation be clinically unsatisfactory, it has major implications for the planning and use of health service resources.

Angioplasty, Balloon↗

PubMed2002

Understanding patient perceptions of asthma: results of the Asthma Control and Expectations (ACE) survey.

In spite of support among UK healthcare professionals for asthma guidelines, studies continue to show that many patients fail to reach the suggested management goals. Patient expectations and poor communication may be factors in this failure. This survey assessed patients' asthma control, expectations in respect of asthma and communication with healthcare professionals. A structured questionnaire, designed for self-completion, was developed and distributed to asthma patients at participating pharmacies. A total of 1031 questionnaires were returned. Most of the respondents, even among those feeling well, reported lifestyle restrictions because of asthma. These restrictions were not generally discussed with healthcare professionals. One-third did not perceive the benefits of inhaled corticosteroids. Low expectation may be a major contributor to the poor control seen in this survey. The failure to discuss lifestyle restrictions and symptom levels with healthcare professionals gives little scope for recommendation of appropriate and adequate treatment. Improved communication between healthcare professionals and patients may help such understanding and raise patient expectations.

Adolescent↗

PubMed2002

Quantitative analysis of UHMWPE wear debris isolated from the periprosthetic femoral tissues from a series of Charnley total hip arthroplasties.

Submicrometer and micrometer-sized UHMWPE wear particles have been associated with osteolysis and failure of total hip replacements. A previous study by Tipper et al. examined the wear debris isolated from the acetabular periprosthetic tissues from 18 Charnley total hip replacements, and compared this data to the tribological variables of the prostheses. The present study aimed to isolate the UHMWPE wear debris from the femoral periprosthetic tissues from 10 of the same cohort of patients, and compare it with the debris isolated from the corresponding acetabular tissues. A variety of particle morphologies were observed, discrete submicrometer particles, along with flakes and fibrils. The particle size distributions ranged from 0.1 to >250 microm, however, the largest particles were only found in samples when the femoral head damage was characterised as low (R(pm) < 0.2 microm). The mode of the frequency distribution of particles was in the range of 0.1-0.5 microm for all the femoral tissues. Considerable variations were found in the mass distributions of the wear particles as a function of size for different patients. The net mass of debris isolated from the femoral tissues was significantly lower (p < 0.05, Student's t-test) than from the corresponding acetabular tissues. This along with considerable spatial variation in the net mass of debris isolated from the different regions of the same sample of acetabular tissue, indicates that the transportation of the debris has a marked effect on the net mass of debris accumulated in different tissues.

Acetabulum↗

PubMed2002

Pilot-scale study of an anaerobic baffled reactor for the treatment of domestic wastewater.

Large proportions of South Africans live in areas with inadequate sanitation and a poor infrastructure for waterborne sanitation. Service providers are looking for alternative wastewater treatment options. The anaerobic baffled reactor is being considered as a decentralised sanitation option in these areas. A 3,200 L reactor was built and is currently being evaluated at a wastewater treatment works. The reactor was built based on experiences gained from working with a laboratory reactor (10 L) and predicted flow patterns observed on a computational fluid dynamics model. The design and construction of the reactor will be discussed in this paper. The feed to the reactor consists of screen degritted sewage and the flow to the reactor is maintained by means of a programmable logic controller. The pilot-plant layout is discussed in this paper. Samples are analysed for chemical oxygen demand, pH, alkalinity, ammonia, phosphorus, solids and ash content. Reductions of between 70 and 80% are obtained for COD and the pH values for the effluent samples are within the discharge limits.

Bioreactors↗

PubMed2001

Differential centrifugation separates cardiac sarcolemmal and endosomal membranes from Langendorff-perfused rat hearts.

The application of subcellular fractionation protocols developed in soft tissues to fibrous organs such as the heart is unsuitable given the substantial differences in subcellular structure these tissues exhibit. The purpose of this study was to develop a simple method for the separation of sarcolemma and endosomes from isolated Langendorff-perfused rat hearts. Hearts were homogenized with either an Ultra-Turrax homogenizer or a hand-held glass tissue grinder. Quantitative immunoblots assessed the enrichment of the sarcolemmal proteins caveolin 3 and the sodium potassium ATPase and the endosomal proteins rab4 and GLUT4 in different membrane fractions. Application of homogenates to sucrose and Percoll density gradients failed to resolve membranes differentially enriched in sarcolemmal or endosomal marker proteins, indicating little difference in density between the sarcolemma and endosomes. However, successive spins of homogenates from a hand-held glass tissue grinder successfully separated the endosomes from the sarcolemma, indicating differences in masses between the two membrane fractions. Approximately 70% of total caveolin 3 and sodium potassium ATPase immunoreactivity was in membrane pellets up to 20,000g and approximately 85% of rab4 and GLUT4 in pellets from 20,000-100,000g. In addition, 86% of ouabain-sensitive ATPase activity (sodium potassium ATPase activity) was in membrane pellets up to 20,000g. Therefore, sarcolemmal membranes were pelleted up to 20,000g, and endosomal membranes between 20,000 and 100,000g. Regional ischemia (40 min) followed by reperfusion (60 min) caused the translocation of GLUT4 (but not rab4) from the endosomal membranes to the sarcolemma in the area of the heart subjected to ischemia.

Animals↗

PubMed2001

Survey of infections due to Staphylococcus species: frequency of occurrence and antimicrobial susceptibility of isolates collected in the United States, Canada, Latin America, Europe, and the Western Pacific region for the SENTRY Antimicrobial Surveillance Program, 1997-1999.

Between January 1997 and December 1999, bloodstream isolates from 15,439 patients infected with Staphylococcus aureus and 6350 patients infected with coagulase-negative Staphylococcus species (CoNS) were referred by SENTRY-participating hospitals in the United States, Canada, Latin America, Europe, and the Western Pacific region. S. aureus was found to be the most prevalent cause of bloodstream infection, skin and soft-tissue infection, and pneumonia in almost all geographic areas. A notable increase in methicillin (oxacillin) resistance among community-onset and hospital-acquired S. aureus strains was observed in the US centers. The prevalence of methicillin (oxacillin)-resistant S. aureus varied greatly by region, site of infection, and whether the infection was nosocomial or community onset. Rates of methicillin resistance were extremely high among S. aureus isolates from centers in Hong Kong and Japan. Uniformly high levels of methicillin resistance were observed among CoNS isolates. Given the increasing multidrug resistance among staphylococci and the possible emergence of vancomycin-resistant strains, global strategies are needed to control emergence and spread of multiply resistant staphylococci.

Anti-Bacterial Agents↗

PubMed2001

Functional hemizygosity of PAFAH1B3 due to a PAFAH1B3-CLK2 fusion gene in a female with mental retardation, ataxia and atrophy of the brain.

We report on the molecular characterization of a translocation t(1;19)(q21.3;q13.2) in a female with mental retardation, ataxia and atrophy of the brain. Sequence analysis of the breakpoints revealed an ALU:-repeat-mediated mechanism of recombination that led to truncation of two genes: the kinase CLK2 and PAFAH1B3, the gene product of which interacts with LIS1 as part of a heterotrimeric G protein complex PAF-AH1B. In addition, two reciprocal fusion genes are present. One expressed fusion gene encodes the first 136 amino acids of PAFAH1B3 followed by the complete CLK2 protein. Truncated PAFAH1B3 protein lost its potential to interact with LIS1 whereas CLK2 activity was conserved within the fusion protein. These data emphasize the importance of PAF-AH1B in brain development and functioning and demonstrate the first fusion gene apparently not associated with cancer.

Abnormalities, Multiple↗

PubMed2001

Tamoxifen in the treatment of advanced or recurrent endometrial carcinoma: a Gynecologic Oncology Group study.

PURPOSE: In two large Gynecologic Oncology Group studies of patients with advanced or recurrent endometrial carcinoma and no previous systemic therapy, progestins have demonstrated activity against advanced or recurrent endometrial carcinoma with response rates between 15% and 25%. Tamoxifen has been reported as variously active or inactive with or without previous systemic therapy. The purpose of this study was to determine whether tamoxifen exhibits enough activity in patients with advanced or recurrent endometrial carcinoma, who have not received systemic therapy, to warrant a phase III trial. PATIENTS AND METHODS: Sixty-eight eligible patients with advanced or recurrent endometrial carcinoma received oral tamoxifen 20 mg bid until toxicity was unacceptable or disease progressed. RESULTS: Three complete (4%) and four partial (6%) responses were observed for an overall response rate of 10% (90% confidence interval [CI], 5.7% to 17.9%). Patients with tumors that were more anaplastic tended to respond less frequently. The median progression-free survival for all 68 eligible patients was 1.9 months (90% CI, 1.7 to 3.2 months). The median survival was 8.8 months (90% CI, 7.0 to 10.1 months). CONCLUSION: Tamoxifen demonstrated modest activity at best against endometrial carcinoma and does not warrant further investigation as a single agent for this disease. Ongoing trials will assess the sequential use of tamoxifen and progestational agents.

Aged↗

PubMed2001

Small bowel obstruction: the role of computed tomography in its diagnosis and management with reference to other imaging modalities.

Small bowel obstruction is a leading cause of acute surgical admissions for abdominal pain. There is an increasing tendency for initial conservative management rather than immediate operative intervention, as a proportion of cases will resolve spontaneously. This has resulted in a growing reliance on radiological investigations to reassure the surgeon that medical therapy can be safely instituted. The onus therefore rests with radiologists to guide their surgical colleagues by correctly interpreting the plain abdominal radiograph and suggesting appropriate further investigation if warranted. Recently, computed tomography (CT) has been proposed as the test of choice to define the level and cause of acute small bowel obstruction and to identify complications such as ischaemia and perforation which will prompt surgical intervention. This review will discuss the utility of early CT in the diagnosis of acute small bowel obstruction and outline its impact on patient management.

Acute Disease↗

PubMed2001

Transgenic GNA expressing potato plants augment the beneficial biocontrol of Lacanobia oleracea (Lepidoptera; Noctuidae) by the parasitoid Eulophus pennicornis (Hymenoptera; Eulophidae).

The effect of expressing the gene encoding snowdrop lectin (Galanthus nivalis agglutinin, GNA) in transgenic potato plants, on parasitism of the phytophagous insect pest Lacanobia oleracea by the gregarious ectoparasitoid Eulophus pennicornis, was investigated in glasshouse trials. Expression of GNA (approx. 1.0% total soluble protein) by transgenic plants significantly reduced the level of pest damage, thus confirming previous studies. Furthermore, the presence of the parasitoid significantly reduced the levels of damage incurred either by the transgenic or control plants when compared to those plants grown in the absence of the parasitoid. For the GNA expressing plants the presence of the parasitoid resulted in further reductions (ca. 21%) in the level of damage caused by the pest species. The ability of the wasp to parasitise and subsequently develop on the pest larvae was not altered by the presence of GNA in the diet of the host. E. pennicornis progeny that developed on L. oleracea reared on GNA expressing plants showed no significant alteration in fecundity when compared with wasps that had developed on hosts fed on control potato plants, although mean size and longevity of female parasitoids was significantly reduced. The number of F2 progeny produced by parasitoids derived from hosts fed on GNA expressing plants was not significantly different to those produced by parasitoids from hosts fed control plants. Results from the present study demonstrate that the use of transgenic plants expressing insecticidal proteins can be compatible with the deployment of beneficial insects and that the two factors may interact in a positive manner.

Animals↗

PubMed2001

A randomized, double-blind, placebo-controlled study of itraconazole capsules for the prevention of deep fungal infections in immunodeficient patients with HIV infection.

OBJECTIVES: To determine whether systemic or deep fungal infections can be prevented, a double-blind, placebo-controlled, phase III trial of itraconazole prophylaxis was undertaken in HIV-infected patients. METHODS: HIV-1 infected patients with CD4 counts < 300 cells/microL were treated with itraconazole (200 mg per day) or matching placebo and followed for 2 years. Development of deep fungal infections, episodes of mucocutaneous candidiasis, change in CD4 count, survival and safety data were collected at each study visit. RESULTS: Three hundred and seventy-four patients received study medication, 187 were given itraconazole and 187 matching placebo. Time to development of deep fungal infection did not differ between groups, in an intention to treat analysis. Low CD4 cell count and prior use of Pneumocystis carinii pneumonia (PCP) prophylaxis were significantly associated with a more rapid development of deep fungal infection (P = 0.044 and 0.017, respectively). Itraconazole treatment significantly reduced the incidence of oral candidosis (25% vs. 48% P < 0.001) and time to development of oral candidosis (508 vs. 413 days, P < 0.001) but not the number of deep fungal infections (11 vs. 13). Survival did not differ significantly between groups (nine vs. 14 deaths). CD4 counts decreased significantly over time in both study arms. Adverse events did not differ between groups; 20% vs. 23% stopped study medication due to an adverse experience. CONCLUSIONS: Although itraconazole prophylaxis significantly reduced the number and time to development of oral candidosis, too few episodes of deep fungal infection were noted to determine whether itraconazole prophylaxis was effective for this condition. Chronic itraconazole treatment is well tolerated in HIV-infected patients with marked immunodeficiency.

AIDS-Related Opportunistic Infections↗

PubMed2001

Assessing depression in drug- and alcohol-dependent subjects: the utility of a cognitive-based approach.

Our objective was to report the development of a measure designed to assess depression severity in those with drug and or alcohol problems not confounded by somatic items that may more reflect the impact of drug and alcohol problems rather than depression itself. A questionnaire was derived with 49 items, each assessing cognitive aspects of depression. Subjects with drug and or alcohol problems completed the measure and a standard self-report depression inventory and were assessed for depression presence and severity by a psychiatrist, who used a structured case-finding measure to complement a semi-structured clinical assessment. A high percentage of the sample was found to be depressed. Total scores on the new measure correlated highly with scores on the two other depression reference measures, supporting its validity as a measure of depression severity. A refined set of 14 items was also identified as a valid measure of depression severity, whereas a determined cut-off established high assignment accuracy when examined against the clinical judgement of caseness. In conclusion, the refined 14-item set has been validated as a depression measure in those with drug and alcohol disorders, whereas the item content may assist clinicians to frame screening questions in assessing such patients.

Adult↗