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Biomedical subjects

B M Jones

Publications and source records attributed to B M Jones.

At least 91 records · Page 5Linked to original sources
PubMed1993

Idiopathic CD4+ T-lymphocytopenia--an analysis of five patients with unexplained opportunistic infections.

BACKGROUND: Although patients with idiopathic CD4+ T-lymphocytopenia and serious opportunistic infections have been described previously, the clinical and immunologic features of this condition have not been well defined. METHODS: We studied in detail five patients with idiopathic CD4+ T-lymphocytopenia. The studies included serologic testing, culture, and polymerase chain reaction for the human immunodeficiency virus (HIV) types 1 and 2, serologic testing for the human T-cell lymphotropic virus (HTLV) types I and II, lymphocyte phenotyping, immunoglobulin quantitation, and lymphocyte-transformation assays, as well as attempts to isolate a retroviral agent. The results were compared with those in HIV-infected persons matched for CD4+ T-cell counts and with those in normal controls. We also studied the spouses of patients and the blood donors for one patient. RESULTS: In these five patients, there was no evidence of either HIV or HTLV infection. All the patients had both low percentages and low counts of CD4+ T cells, with relative increases in percentages, but not counts, of CD8+ cells. Numbers of B cells and natural killer cells were generally normal. As compared with HIV-infected persons, our patients had lower percentages and counts of CD8+ cells and more lymphopenia. CD4+ counts were relatively stable over time. Instead of the high immunoglobulin levels seen in HIV infection, these patients had normal or slightly low levels of immunoglobulins. The lymphocyte-transformation response to mitogens and antigens was depressed. Results in spouses and blood donors were normal. CONCLUSIONS: Idiopathic CD4+ T-lymphocytopenia differs from HIV infection in its immunologic characteristics and in its apparent lack of progression over time. Nothing about the immunologic or viral-culture studies performed in these patients or about their family members or blood donors suggests that a transmissible agent causes this condition.

Adult↗
PubMed1993

CD4 T-lymphocyte determinations on whole blood specimens using a single-tube three-color assay.

We evaluated a flow cytometric method for determining the proportion of CD4-positive T lymphocytes in whole blood using a single three-color tube containing fluorochrome-labeled CD45, CD3, and CD4. Various ways of gating this sample were evaluated and results were compared with data obtained in our standard six-tube, two-color assay gated on light scatter parameters. Excellent correlation was found between the three-color analysis using a CD45/side scatter gate and the standard two-color analysis with a light scatter gate. This single-tube three-color test is a promising assay for monitoring CD4+ T-lymphocytes.

Adult↗
PubMed1993

B-cell and T-regulatory cell dysfunction in six Chinese children with hypogammaglobulinaemia.

We report six Chinese boys with hypogammaglobulinaemia. All but one had very low or undetectable circulating B-lymphocytes, two had reversed CD4/CD8 ratios (in one of whom this latter became normal), one had reduced lymphocyte proliferative responses to concanavalin A and pokeweed mitogen and three had deficient responses to OKT3. Generation of antibody-secreting cells in response to pokeweed mitogen was markedly defective in all patients. Co-cultures of purified lymphocyte subsets from the patients with those of normal donors revealed that in addition to B-cell deficiency seen in all patients, two had T-helper cell deficiency and two had T-suppressor cell hyperactivity. One of the latter patients was treated with cimetidine in an attempt to ablate histamine type 2 receptor-bearing suppressor cells: the absolute number of such cells was temporarily reduced but there was no concurrent correction of the functional hyperactivity. These studies point to the variable nature of T-regulatory cell deficiencies in hypogammaglobulinaemia.

Adolescent↗
PubMed1993

Percentile ranges for serum IgG subclass concentrations in healthy Chinese children.

In order to establish normal reference ranges of serum immunoglobulin G subclasses for different age groups in Chinese, we measured the four IgG subclasses by radial immunodiffusion using polyclonal antisera in 350 normal healthy subjects (148 males and 202 females) recruited from the community. There was no significant sex difference for all the four IgG subclasses. Using Box-Cox transformation, we constructed smooth age-dependent percentile curves for the four IgG subclasses. For the 50th percentile values, the plateaus for IgG1 to IgG4 are respectively 970 mg/dl at 13 years old, 481 mg/dl at 18, 48 mg/dl at 17 and 80 mg/dl at 13. Methodology, reagents, environmental and genetic factors might be responsible for the observed difference among the various reports. The IgG2 level in our Chinese population seemed to be higher than that in Caucasians, which might account for the very low incidence of invasive Haemophilus influenzae type b disease among the Chinese. Our IgG1 level also plateaued later and at a higher level than that in other studies.

Adolescent↗
PubMed1993

CD5-positive and CD5-negative rheumatoid factor-secreting B cells in IgA nephropathy, rheumatoid arthritis and Graves' disease.

The relative contributions of CD5+ and CD5- B-cells in production of rheumatoid factors (RF) was evaluated in polyclonally activated B-cells from patients with IgA nephropathy (IgAN), rheumatoid arthritis (RA) and Graves' disease (GD). In IgAN and RA, diseases in which RFs are believed to be involved in pathogenesis, there were 10- and 4-fold decreases respectively in CD5+ IgG-RF-secreting B-cells compared with controls. Furthermore, the number of CD5- IgG-RF- and IgA-RF-secreting B-cells were increased 12- and 14-fold in IgAN and 9- and 4-fold in RA. Such abnormalities were not apparent in GD, in which RFs have not been implicated in pathogenesis. These findings are compatible with the concept of CD5+ RF-secreting B-cells normally acting to prevent production of potentially pathogenic RFs by CD5- B-cells. When IgAN or RA patients' B-cells were activated in the presence of control instead of autologous CD4+ cells, numbers of RF-secreting CD5- B-cells were reduced to the levels seen with control B-cells plus control T-helper cells. Presumably lymphokine secretion profiles of T-helper cells would be important in determining whether CD5+ or CD5- B-cells are activated to secrete RFs, and perhaps therapeutic manipulation of these profiles could restore normal activity of CD5+ B-cells in IgAN and RA.

Adolescent↗
PubMed1993

Intra-abdominal complications following prolonged cardiopulmonary resuscitation.

A patient who underwent prolonged cardiopulmonary resuscitation developed an acute abdomen in the early post-arrest period which required laparotomy. Operative findings were of a perisplenic haematoma and infarction of the caecum. The latter has not previously been reported in this setting. A review of the literature reveals that many abdominal complications may occur following external cardiac massage. Difficulties in investigation and management are discussed.

Abdomen, Acute↗
PubMed1992

Pulmonary angiography in a non-teaching hospital over a 12-year period.

OBJECTIVE: To report the safety of pulmonary angiography in a non-teaching hospital and discuss the place of this investigation in the diagnosis of pulmonary embolism. DESIGN AND SETTING: A retrospective review of all patients undergoing pulmonary angiography over a 12-year period, November 1979 to October 1991, at Dandenong Hospital, Melbourne. A protocol was established whereby each procedure was performed with the assistance of staff and equipment from the intensive care unit to provide haemodynamic monitoring and measurement of pulmonary artery pressures. PATIENTS: During the review period 114 patients underwent pulmonary angiography, most (108) for suspected pulmonary embolism. RESULTS: One hundred and fifteen pulmonary angiograms were performed, and no deaths related to the procedure occurred. Complications included perforation of the right atrium in three patients, with no sequelae. Cardiac arrhythmias were common but self-limiting. CONCLUSION: In our series, pulmonary angiography was a safe procedure if undertaken with the appropriate monitoring measures. A protocol which includes the participation of the intensive care unit has proved helpful. In addition, it was found that clinical symptoms and signs were unreliable and in 24 patients who also had ventilation-perfusion (V/Q) scans, only seven scans were accurate. A review of the literature indicates that V/Q scans lack specificity and that pulmonary angiography may be performed safely. The latter investigation should be more frequently performed.

Angiography↗
PubMed1992

Longitudinal study of quality of life and psychological adjustment after cardiac transplantation.

OBJECTIVE: To assess the psychological adjustment and quality of life of a sample of cardiac transplant recipients over time. DESIGN: The patients were consecutive recipients of new hearts which were transplanted between November 1984 and December 1986. Thirty-eight patients were entered into the study, but at final follow-up only 27 were assessed; six patients had died and five could not be contacted. Patients were seen before transplantation, at discharge, then at 4, 8 and 12 months after transplantation and finally at a mean of 4.2 years after transplantation. They were assessed by means of standardised questionnaires. The results were compared across time and correlated with demographic data and medical data collected at the initial assessment. Only patients who were alive and responded at each point of follow-up were included in the study. SETTING: All patients were seen at St Vincent's Public Hospital and were tertiary care patients. MAIN OUTCOME MEASURES: The main outcome measures were anxiety, depression and well-being. These measures were assessed by means of the Spielberger State Trait Anxiety Scale, the Beck Depression Inventory and the Campbell Well-Being Scale. At the four year follow-up the Nottingham Health Profile was also used. RESULTS: Scores for anxiety, depression and well-being improved significantly after transplantation and did not deteriorate over time. No significant correlations were found between psychological measures and medical or demographic data. CONCLUSIONS: The results showed no evidence of mood disorder and a high level of well-being in this sample of cardiac transplant recipients up to four years after transplantation.

Adaptation, Psychological↗
PubMed1992

Defective B-cell and regulatory T-cell function in Wiskott-Aldrich syndrome.

We report two Chinese boys with Wiskott-Aldrich syndrome presenting with gastro-intestinal bleeding, eczema and recurrent infection. They had thrombocytopenia and the mean platelet volume was small. Serum IgG and IgA were elevated and lymphocyte proliferation in response to phytohaemagglutinin, concanavalin A and pokeweed mitogen was defective. Despite documented herpes simplex virus type 1 and cytomegalovirus infection in one patient, he did not mount any humoral response. The generation of antibody-secreting cells in response to pokeweed mitogen was markedly defective in a plaque-forming cell assay. Both patients' regulatory T-cell and B-cell functions were defective in this assay. The genetic defect in Wiskott-Aldrich syndrome therefore affects T-cells, B-cells and platelets.

Antibody Formation↗
PubMed1992

Relationship between intracranial pressure and intracranial volume in craniosynostosis.

Premature fusion of cranial sutures in craniosynostosis has been thought to lead to craniostenosis, which in turn may lead to increased intracranial pressures. In 41 consecutive patients with craniosynostosis, intracranial pressure and intracranial volume were measured. Of the 41 patients, 38 (92.6%) had raised intracranial pressure but only 4 (9.7%) had a decreased skull volume. In the present study, there is no correlation between intracranial volume and intracranial pressure. This study confirms that the measurement of intracranial volume, a non invasive procedure, cannot be used to assess intracranial pressure and to avoid an invasive procedure.

Aging↗
PubMed1992

Complications in paediatric craniofacial surgery: an initial four year experience.

107 children undergoing transcranial craniofacial surgery in a paediatric hospital have been reviewed to assess the incidence and type of complications which arose. This represents the first 4 years' experience of the craniofacial team. There were no deaths or permanent adverse sequelae of surgery. A total of 53 complications were seen in 42 patients. In 9.3% of patients they were potentially life-threatening, serious in 12.1% and of a minor nature in 28%. The more serious complications were related either to haemorrhage and/or vasovagal shock at operation or to infection post-operatively. Infants undergoing monoblock frontofacial advancements and those with tracheostomies were at particular risk.

Adolescent↗
PubMed1992

Cell-cycle progression rates and sister chromatid exchange frequencies in the bone marrow of patients with myelodysplastic syndrome and acute myeloid leukemia.

The proliferation characteristics of leukemic cells may be a determining factor in disease course and response to therapy. The present study compares the rate of cell-cycle progression in the bone marrow of 16 hematologically normal subjects, 19 patients with acute myeloid leukemia (AML), and 23 patients with myelodysplastic syndrome (MDS). The frequency of sister chromatid exchanges (SCE) in bone marrow cells is also compared. MDS and AML patients showed a reduction in the rate of cell-cycle progression compared with normal subjects. Patients with 'high risk' MDS (RAEB/RAEB-t) did not differ significantly from patients with AML but had a significantly slower rate of cell-cycle progression than patients with 'low-risk' MDS (PASA/RA). There was no correlation between the rate of cell-cycle progression and clonal karyotype status or the percentage of blast cells in either MDS or AML. There were no significant differences in SCE frequency between normal subjects and MDS or AML patients.

Acute Disease↗
PubMed1992

A field study of the generation of nitrate in a hill cap cloud.

A field experiment to investigate the formation of nitrate as an airstream passes through a hill cap cloud has been performed at the UMIST field station on Great Dun Fell. It has been shown that the aerosol nitrate concentration increased by about 0.5 microg m(-3) as the airstream passed through the cloud during the night. At sunrise the nitrate production disappeared. It is suggested that the most likely mechanism for this nitrate production was due to the solution of N2O5 and NO3 formed from the reaction of NO2 with O3. These higher oxides build up overnight in the absence of short wave radiation to photolyse them. Other possible mechanisms of nitrate production are also discussed.

Journal Article↗
PubMed1992

Chromosome aberrations following cytotoxic therapy in patients in complete remission from lymphoma.

The frequency of chromosome aberrations in the peripheral blood of patients successfully treated for Hodgkin's disease (HD) and non-Hodgkin's lymphoma is compared with that seen in age-matched haematologically normal subjects. Findings are considered in relation to risk factors associated with the development of secondary myelodysplastic syndrome (MDS) or acute myeloid leukaemia (AML). Overall aberration frequencies were not significantly increased in patients compared with normal subjects. However, there were differences in aberration type. The frequency of exchanges was significantly higher among patients (P less than 0.01) and the frequency of gaps lower (P less than 0.0005). The mean frequency of exchanges was also greater in patients receiving multiple compared to single courses of therapy (P less than 0.0005) and in patients receiving radiotherapy or combined modality therapy compared to chemotherapy alone (P less than 0.005 and P less than 0.0005). Four patients had aberration frequencies greater than 2 SD above the patient mean. One of these was also found to have a mutation of the ras oncogene. None of the patients has yet developed secondary MDS/AML.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

The effect of palate repair on otitis media with effusion.

Cleft palate in children is very frequently associated with otitis media with effusion. In this prospective study of 150 cleft palate children aged between 2 and 18 months, the prevalence of otitis media with effusion at myringotomy before palate repair was 92 percent. Otoscopic and tympanometric follow-up assessments for 140 children indicate that there is minimal improvement in middle ear status after palate repair. The condition is persistent in 70 percent of children up to 4 years of age. Furthermore, there is no evidence that age at repair or type of cleft is influential. These findings have implications for otologic management of cleft palate children. Early routine unilateral ventilation to ensure adequate hearing but minimize the morbidity of ventilation tubes is advocated.

Cleft Palate↗
PubMed1992

Intracranial pressure and intracranial volume in children with craniosynostosis.

Intracranial volume and intracranial pressure have been measured in 66 children with craniosynostosis, 48 boys and 18 girls. The premature fusion of skull sutures is assumed to restrict skull growth and predispose to elevated intracranial pressure. Thirteen children (20 percent) had raised intracranial pressure and demonstrated a significant restriction of skull growth. In this series, volume measurement alone, however, did not serve as a reliable predictor that the intracranial pressure was raised.

Adolescent↗