Search PubMed⌕ Search

Biomedical subjects

J Gibson

Publications and source records attributed to J Gibson.

At least 73 records · Page 4Linked to original sources

T-cell expansions in patients with multiple myeloma have a phenotype of cytotoxic T cells.

The presence of T-cell clones in peripheral blood has been previously shown to be associated with a survival advantage in patients with multiple myeloma and suggests that the expanded T-cell populations may be involved in an anti-tumour response. We studied the T-cell receptor (TCR) repertoire of 38 patients with myeloma to identify and characterize the expanded T-cell populations by flow cytometry. T-cell expansions were found in 79% of the patients. The expansions occurred randomly among the 21 variable regions of the TCR beta chain (Vbeta) studied, representing 62% of the V-beta repertoire, and were stable during an 18-month follow-up. The phenotype of the expanded V-beta populations was predominantly CD8+, CD57+, CD28- and perforin+, which differed significantly from the other non-expanded Vbeta populations. The expression of the apoptosis markers Fas (CD95) and bcl-2 were similar between the expanded and non-expanded Vbeta populations. In conclusion, expanded T-cell populations were frequent in patients with myeloma, they remained unchanged during follow-up and had phenotypic characteristics of cytotoxic T cells. These data add further support to the concept that the T-cell expansions may have an immunoregulatory role in myeloma.

Aged↗

Quality assurance by a commercial flow cytometry method of leucodepletion of whole blood donations: initial application of universal testing and proposals for a batch-release sampling plan.

We have used the Becton-Dickinson LeucoCOUNT test to monitor residual leucocytes in whole blood by flow cytometry following leucodepletion filtration. This test was found to be quick, robust and reliable, and allowed measurement of residual leucocytes down to 2.25 x 104 leucocytes per unit, which was found to match approximately the limit of filter proficiency. The results of testing > 1000 units showed a lognormal distribution with means between log(10) 4.864 (0.73 x 105) and log(10) 5.016 (1.04 x 105) leucocytes per unit in the three different homogeneous groups of filtered units studied. The numbers of units with residual leucocytes exceeding the 5 x 106 upper threshold were 1/577, 2/457 and 0/87 in these groups. The filtration processes were validated according to the published BEST working party guidelines and were well within the 99% confidence and 95% tolerance target for the 5 x 106 upper threshold set for the UK. A sampling plan based on British Standard BS 6001 with elimination of outliers by the extreme studentized deviate (Grubbs' test) was evaluated on random samples from these groups and has been adopted locally as a prospective batch-release criterion for release of leucodepleted blood.

Blood Donors↗

Oral staphylococcal mucositis: A new clinical entity in orofacial granulomatosis and Crohn's disease.

OBJECTIVE: Orofacial granulomatosis and the oral manifestations of Crohn's disease comprise many clinical features, of which stomatitis is one. The purpose of this study was to establish a role for Staphylococcus aureus in mucositis affecting some patients with orofacial granulomatosis or oral Crohn's disease. STUDY DESIGN: Four patients (2 with orofacial granulomatosis and 2 with oral Crohn's disease), from a total of 450 patients examined over 10 years, had stomatitis involving the entire oral mucosa, from which S aureus was cultured by the oral rinse technique. These patients were treated with flucloxacillin or erythromycin. RESULTS: A heavy growth of S aureus was isolated from the mouth of each patient. All 4 patients responded to treatment with flucloxacillin or erythromycin. CONCLUSIONS: S aureus is a potential cause of panstomatitis in patients with orofacial granulomatosis or Crohn's disease. This infection responds rapidly to antimicrobial treatment.

Adolescent↗

Effects of icodextrin in automated peritoneal dialysis on blood pressure and bioelectrical impedance analysis.

BACKGROUND: Glucose absorption from glucose-based dialysis fluids limits ultrafiltration from the daytime dwell in automated peritoneal dialysis (APD). Icodextrin may allow greater ultrafiltration during the daytime period in APD, enhancing fluid control. METHODS: A 7.5% icodextrin dialysate was compared with a 2. 27% glucose dialysate for the daytime dwell in 14 subjects on APD. Blood pressure, weight and body water compartments estimated by multifrequency bioelectrical impedance (MFBIA) were determined in subjects using 2.27% glucose as the daytime dwell and then repeated 1 month after switching to icodextrin. RESULTS: Icodextrin resulted in symptomatic hypotension requiring reduction of antihypertensive medication in six of the 14 patients. Despite this reduction in treatment, systolic blood pressure fell from 142.4 (23.9) mmHg to 122.9 (17.7) mmHg, P<0.005, and diastolic blood pressure tended to fall from 82.8 (9.8) mmHg to 76.8 (10.1) mmHg, P=0.075. Change in systolic blood pressure significantly correlated with changes in weight (r=0.62, P<0.05) and MFBIA estimates of total body water (TBW) (r=0.56, P<0.05), extracellular water (ECW) (r=0.79, P<0.002), extra/intracellular water ratio (ECW/ICW) (r=0.72, P<0.01) and derived resistances R(ecf) of ECW (r=-0.69, P<0.01) and R(inf) of TBW (r=-0.66, P<0.02). Changes in diastolic blood pressure significantly correlated with changes in ECW (r=0.64, P<0.02) and ECW/ICW ratio (r=0.58, P<0.05), and almost significantly with R(ecf) (r=-0.51, P=0.08) and R(inf) (r=-0.52, P=0.07) estimated by MFBIA, but not with changes in weight or TBW. CONCLUSIONS: Use of icodextrin for the daytime dwell in APD results in improved fluid balance and blood pressure control compared with 2.27% glucose. MFBIA detected clinically important changes in fluid content in these patients.

Adult↗

The role of allergy in oral mucosal diseases.

We retrospectively assessed the prevalence of positive results to cutaneous patch testing, and the relevance of exclusion of identified allergens in the disease process, in 1252 patients with oral mucosal diseases presenting to the Department of Oral Medicine in Glasgow Dental Hospital and School and referred to the Contact Dermatitis Investigation Unit in Glasgow Royal Infirmary. The prevalence of patch-test positivity in each disease cohort was compared with that in 100 control volunteers. Patients with oral mucosal diseases were significantly more likely to have demonstrable hypersensitivity to food additives, especially benzoic acid, and perfumes and flavourings, especially cinnamaldehyde, than controls, and avoidance therapy caused improvement in the majority. Patch testing and the resultant avoidance therapy are useful adjuncts in the management of oral mucosal diseases.

Adolescent↗

99Tcm-HMPAO leucocyte labelling in orofacial granulomatosis and gastrointestinal Crohn's disease in childhood and early adulthood.

Orofacial granulomatosis is a granulomatous inflammatory disorder, affecting the soft tissues of the face and mouth. The predominant feature is disfiguring lip swelling. Patients with this condition may be exhibiting a Type IV hypersensitivity reaction to dietary or environmental allergens, or these may be the orofacial manifestations of underlying gastrointestinal Crohn's disease. The results of 99Tcm-HMPAO leucocyte labelling of the gastrointestinal tract in 14 patients with orofacial granulomatosis and 15 patients with known gastrointestinal Crohn's disease are presented, indicating that this is a useful and non-invasive screening test for the identification of gastrointestinal Crohn's disease in paediatric and young adult patients presenting with orofacial granulomatosis.

Adolescent↗

The role of the general dental practitioner in detection and prevention of oral cancer: a review of the literature.

Over the last two decades little progress appears to have been made in reducing the incidence and number of deaths associated with oral cancer. The most recently available Scottish data indicate a steady rise in both incidence of, and mortality rates from, tongue and 'mouth' cancer, supporting previous observations of a steady rise in the incidence of oral cancer since the mid 1970s. Very little improvement in 5-year survival rates for oral cancer has been observed in England and Wales and, over the last 30 years, survival rates in Scotland have actually declined. Although many dentists are committed to examining the mouth for oral cancer, the majority still feel uncomfortable with involvement in patient education. Clearly scope exists for dental practitioners to improve patient awareness of both oral cancer itself and the risk factors associated with the disease. Dental teams should be aware of the opportunities within dental practice to contribute to preventive initiatives--such as smoking cessation.

Adult↗

The reduction of broken appointments in general dental practice: an audit and intervention approach.

PURPOSE OF STUDY: Accumulation of time lost because of broken appointments in general dental practice can lead to an inefficiently-run practice and may also lead to reduced financial income. This study assessed the reasons for patients failing to attend and analysed the effect of two simple interventions in reducing the numbers of broken appointments. BASIC PROCEDURES: This study audited the causes of broken appointments in a Glasgow dental practice over a four-month period and, in a second four-month period, analysed the effect of using two new methods of patient information in reducing the number of broken appointments in two target groups of the practice population. MAIN FINDINGS: The majority of patients failing to attend for dental treatment were unemployed. Simple changes to recall letters and appointment cards significantly reduced the rates of failed appointments in patients attending the practice. PRINCIPAL CONCLUSIONS: Simple modification to existing practice systems (recall letters and appointment cards) led to a statistically significant reduction in the number of broken appointments.

Appointments and Schedules↗

The bone marrow plasma cell labeling index by flow cytometry.

The bone marrow plasma cell labeling index is the most important prognostic indicator for patients with multiple myeloma. Traditionally, this test has been performed as a two color immunofluorescent microscope technique which is time consuming and requires a degree of subjectivity in its interpretation. We have assessed various adaptations of this method to flow cytometry. A bromodeoxyuridine method has been compared with a propidium iodide DNA method to detect cells in S phase and CD38-FITC has been compared with CD38-FITC + CD138-FITC and CD38-biotin + streptavidin FITC to identify plasma cells. The mean channel fluorescent intensity of the plasma cell peaks for each of these markers was 12. 7, 17.4 and 35.3 respectively demonstrating the superiority of CD38-biotin + streptavidin FITC. Analysis after propidium iodide staining provided a good correlation with the slide technique (r = 0. 71; P < 0.0001) but the bromodeoxyuridine method did not correlate with the slide method (r = 0.09; P = NS). The labeling index values obtained from either of the flow methods were greater than the microscopic method. Thus a labeling index of >4% will replace the traditional >1% threshold for identifying patients with a significantly increased labeling index. The advantages of the new method are that it takes less time to perform, is more objective and provides additional data on ploidy and cell cycle status.

ADP-ribosyl Cyclase↗

Genomic organization and chromosomal localization of the human Coxsackievirus B-adenovirus receptor gene.

Myocarditis and dilated cardiomyopathy (DCM) are common causes of morbidity and mortality in children. Many studies have implicated the enteroviruses and, particularly, the Coxsackievirus-B family as etiologic agents of the acquired forms of these diseases. However, we have shown the group-C adenoviruses to be as commonly detected as enteroviruses in the myocardium of children and adults with these diseases. It has remained something of a conundrum why two such divergent virus families cause these diseases. The recent description of the common human Coxsackievirus B-adenovirus receptor (CAR) offers at least a partial explanation. In order to characterize the CAR gene, we screened a bacterial artificial chromosomal (BAC) library (RPCI11) using a polymerase chain reaction (PCR) product derived from the 3' end of the CAR cDNA sequence. This identified 13 BACs that were further characterized by PCR amplification of seven contiguous regions of the entire cDNA sequence. Eleven of the BACs were determined to encode pseudogenes while the other two BACs (131J5 and 246M1) encoded the presumed functional gene. PCR amplification of a monochromosomal hybrid panel indicated the presence of pseudogenes on chromosomes 15, 18, and 21 while the functional gene is encoded on chromosome 21. Fluorescence in situ hybridization analysis indicated that the gene is located at 21q11.2. DNA sequencing of BACs 131J5 and 246M1 revealed the presence of seven exons. The DNA sequences have been determined for each exon-intron boundary, and putative promoter sequences and transcription initiation sites identified. No consensus polyadenylation signal was identified.

Adenoviruses, Human↗

Hemodynamic consequences of high- and low-pressure capnoperitoneum during laparoscopic cholecystectomy.

BACKGROUND: Peritoneal insufflation to 15 mmHg diminishes venous return and reduces cardiac output. Such changes may be dangerous in patients with a poor cardiac reserve. The aim of this study was to investigate the hemodynamic effects of high (15 mmHg) and low (7 mmHg) intraabdominal pressure during laparoscopic cholestectomy (LC) METHODS: Twenty patients were randomized to either high- or low-pressure capnoperitoneum. Anesthesia was standardized, and the end-tidal CO2 was maintained at 4.5 kPa. Arterial blood pressure was measured invasively. Heart rate, stroke volume, and cardiac output were measured by transesophageal doppler. RESULTS: There were 10 patients in each group. In the high-pressure group, heart rate (HR) and mean arterial blood pressure (MABP) increased during insufflation. Stroke volume (SV) and cardiac output were depressed by a maximum of 26% and 28% (SV 0.1 > p > 0.05, cardiac output p > 0. 1). In the low-pressure group, insufflation produced a rise in MABP and a peak rise in both stroke volume and cardiac output of 10% and 28%, respectively (p < 0.05). CONCLUSIONS: Low-pressure pneumoperitoneum is feasible for LC and minimizes the adverse hemodynamic effects of peritoneal insufflation.

Adult↗

Spontaneous regression of an anaplastic large cell lymphoma in the oral cavity: first reported case and review of the literature.

Lymphomas account for 2-5% of all oral malignancies and are the third most common in this site. This case report appears to be the first in the world literature describing spontaneous regression in the oral cavity of a subset of non-Hodgkins lymphomas known as Ki-1 anaplastic large cell lymphomas (ALCL). Ki-1 ALCL account for 2-7% of all non-Hodgkins lymphomas and the clinical presentation is variable; they may arise de novo or in the setting of a separate primary lymphoma and commonly present in the extra-nodal location. Disease severity is also variable with waxing and waning lesions at one extreme which may spontaneously regress to bone marrow involvement in around 12% of cases. This case is especially interesting since the patient is a farmer, given the recent evidence that there may be a link between non-Hodgkins lymphoma and this occupation.

Aged↗

Syngeneic stem cell transplantation for HIV-related lymphoma.

The treatment of human immunodeficiency virus (HIV)-related lymphoma is beset by a number of therapeutic limitations. High-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) for relapsed disease is one option, but may be compromised by unacceptable treatment-related morbidity and mortality. We describe an HIV-positive male with relapsed immunoblastic non-Hodgkin's lymphoma (NHL) who successfully received salvage chemotherapy followed by a syngeneic PBSCT from his HIV-negative (hepatitis C positive) brother. At 15 months post-transplant he remains in complete remission with low-level HIV viral load, an improved CD4 lymphocyte count and absent anti-hepatitis C antibodies. We believe selected patients with relapsed HIV-related NHL should be considered for high-dose therapy.

Adult↗

Factors affecting the outcome of allogeneic bone marrow transplantation for adult patients with refractory or relapsed acute leukaemia.

We evaluated the outcome of allogeneic bone marrow transplantation (BMT) for advanced acute myeloid leukaemia (AML) and acute lymphoblastic leukaemia (ALL) in 383 adult patients in nine Australian adult BMT centres between 1981 and 1997. The median overall survival for the group was 4.8 months, with an estimated 5-year survival of 18%. 28% of patients died of transplant-related toxicities within the first 100 d. Progressive disease was responsible for 48% of deaths. Multi-factor analysis demonstrated that AML (v ALL), disease status (second complete remission [CR2] v others), age (< 40 years) and duration of prior first complete remission (CR1) (> 6 months) were pre-transplant variables significantly associated with improved survival. Acute graft-versus-host disease (GVHD) of any grade reduced the rate of relapse in both AML and ALL, but only grades I-II were associated with improved survival. Both limited and extensive chronic GVHD were associated with increased survival. Only patients with AML in untreated first relapse or CR2, with a duration of CR1 > 6 months, or patients with T ALL, had a 5-year survival > 20%. Transplants for AML in induction failure or pre-B ALL in untreated first relapse or CR2 had an intermediate outcome, with 5-year survival of 10-20%. A 5-year survival of < 10% was observed for patients transplanted for ALL in induction failure or for pre-B ALL or AML in refractory first relapse or beyond CR2. These results suggest that for most adult patients with advanced acute leukaemia an allograft offers only a small chance of cure.

Adolescent↗