Comparison of endpoint data treatment methods for estimation of kinematics and kinetics near impact during the tennis serve.

Tennis stroke mechanics have attracted considerable biomechanical analysis, yet current filtering practice may lead to erroneous reporting of data near the impact of racket and ball. This research had three aims: (1) to identify the best method of estimating the displacement and velocity of the racket at impact during the tennis serve, (2) to demonstrate the effect of different methods on upper limb kinematics and kinetics and (3) to report the effect of increased noise on the most appropriate treatment method. The tennis serves of one tennis player, fit with upper limb and racket retro-reflective markers, were captured with a Vicon motion analysis system recording at 500 Hz. The raw racket tip marker displacement and velocity were used as criterion data to compare three different endpoint treatments and two different filters. The 2nd-order polynomial proved to be the least erroneous extrapolation technique and the quintic spline filter was the most appropriate filter. The previously performed "smoothing through impact" method, using a quintic spline filter, underestimated the racket velocity (9.1%) at the time of impact. The polynomial extrapolation method remained effective when noise was added to the marker trajectories.

Limitations in the ability of NB84 to detect metastatic neuroblastoma cells in bone marrow.

BACKGROUND: The accurate assessment of metastases is an essential component of the staging process for children with neuroblastoma. AIMS: To study the sensitivity of the immunohistochemical marker neuroblastoma 84 (NB84) for the detection of bone marrow infiltrates in children with stage 4 neuroblastoma. METHODS: Primary tumour specimens, bone marrow trephine biopsy specimens and lymph node metastases, taken from children with neuroblastoma that had metastasised to bone marrow, were assessed with a panel of commonly used immunohistochemical markers for neuroblastoma. A comparison was drawn between the sensitivity of the marker NB84 for primary tumours and for bone marrow metastases. RESULTS: NB84 immunolabelled all pre-chemotherapy and post-chemotherapy (n = 24) paired primary tumour specimens, as well as each of a further 20, unpaired, pre-chemotherapy primary tumour specimens. It also labelled all (n = 4) lymph node metastases. Immunolabelling of bone marrow trephine biopsy specimens (21/33) was less sensitive. Of 16 primary tumour specimens with a paired bone marrow trephine biopsy specimen, all immunostained positive, whereas only 62.5% of bone marrow biopsy specimens immunostained positive for NB84. The number of bone marrow biopsy specimens immunostaining for NB84 was significantly lower than the number of paired primary tumour specimens (p = 0.041). CONCLUSIONS: NB84 remains a useful marker for the diagnosis of neuroblastoma in primary tumour specimens, but not for neuroblastoma that has metastasised to bone marrow.

Expression of mu class glutathione S-transferase correlates with event-free survival in childhood acute lymphoblastic leukemia.

Expression of the main classes (pi, mu, and alpha) of glutathione S-transferase (GST) was assessed in the blasts of children presenting with acute lymphoblastic leukemia using an immunohistochemical technique. Bone marrow trephine biopsies obtained at presentation from 71 cases were studied (42 boys, 29 girls; age range, 6 months-14 years; median age, 4 years) and expression was correlated with event-free survival. The period of follow-up was 12-108 months, during which time 21 patients (30%) relapsed. All the samples examined were negative for alpha class GST. Samples from 8 patients, all of whom remained in remission at the time of analysis, were found to be negative for pi class GST at presentation. Samples from 44 (patients were negative for mu class GST (62%); of these, 36 patients (82%) remained in remission. In comparison, of the 27 patients who were positive for mu class GST, only 14 (52%) remained in remission. Analysis of event-free survival demonstrated that expression of mu class GST predicts a 3-fold increased risk of relapse (95% confidence interval, 1.25-7.26). This risk factor appears to be independent of other recognized prognostic factors.

Molecular heterogeneity of variant Philadelphia translocations in childhood acute lymphoblastic leukaemia.

In acute lymphoblastic leukemia (ALL), it is unclear whether variant Philadelphia (Ph) translocations have the same molecular and clinical implications as the classical translocation. Two children with Ph+ ALL with variant translocations are described. One, in whom cytogenetic remission was not achieved, had evidence of translocation of c-abl to chromosome 22, rearrangement of minor breakpoint cluster region (mBCR) and expression of hybrid bcr/abl transcripts. In the other case, no gene rearrangement was found and complete remission was achieved. Variant Ph translocations in childhood ALL are heterogeneous at the molecular level. Molecular studies coupled with observations of clinical outcome are needed in larger numbers of such children to determine whether poor clinical response correlates with bcr/abl involvement and to allow planning of appropriate therapeutic strategies.

Alpha interferon gene deletions in adults, children and infants with acute lymphoblastic leukemia.

DNA from 76 cases of acute lymphoblastic leukemia (ALL) was tested with a cDNA probe encoding the alpha 2B interferon (IFN) gene transcript. Deletions were found in three of ten pre-B, three of 21 T-cell, four of 22 common and one of 23 null ALL cases. Amongst those with null ALL were 20 infants, most with characteristic translocations, none of whom had deletion of alpha IFN genes. The results confirm that alpha IFN gene deletions may occur without visible abnormalities of chromosome 9p and show that they occur across a wide range of ALL phenotypes. The results suggest that alpha IFN gene deletions may be rare events in null ALL of infants but their incidence and cellular consequences remain unknown.

Raised intracellular glutathione levels correlate with in vitro resistance to cytotoxic drugs in leukaemic cells from patients with acute lymphoblastic leukemia.

Lymphoblasts were separated from the peripheral blood or bone marrow of 19 children (age 1-15, median 4 years) and 13 adults (age 18-59, median 47 years) with acute lymphoblastic leukaemia (ALL). Twenty-one samples were examined at presentation (16 from children and five from adults) and 13 at relapse (three children and ten adults). Glutathione (GSH) levels in leukaemic blasts were compared with in vitro sensitivity to a variety of cytotoxic drugs assessed using 3-(4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) as an indicator of cell viability. There was a statistically significant positive correlation between GSH levels and in vitro sensitivity to daunorubicin (Spearman's rank correlation coefficient rs = 0.38, p < 0.04), melphalan (rs = 0.39, p < 0.04) and prednisolone (rs = 0.48, p < 0.01), but not mitozantrone, etoposide or 6-thioguanine. There was no statistically significant difference in median GSH levels between blasts from children and adults or between samples taken at presentation or relapse. The sample median GSH levels in blasts from patients who responded to therapy (n = 21) and those who did not (n = 7) were 1.05 fmol/cell (97.3% confidence interval (CI) 0.78-1.52) and 2.66 fmol/cell (98.4% CI 0.53-5) respectively, and this difference was statistically significant (p < 0.02, Mann-Whitney U test). In two patients for whom paired samples were available, GSH levels in blasts on relapse were greater than 2-fold higher than on presentation. These results provide evidence that elevation of GSH in leukaemic blasts may be associated with resistance to drugs used in the treatment of children and adults with ALL.

De novo acute myeloid leukaemia in patients over 55-years-old: a population-based study of incidence, treatment and outcome. Northern Region Haematology Group.

A 4-year prospective study of de novo acute myeloid leukaemia in patients aged 56 years and over was undertaken in the Northern Region of England (population 3.09 million). The study was conducted to assess the incidence and outcome of treatment in all elderly patients diagnosed between January 1, 1988 and December 31, 1991. Two hundred cases de novo AML were confirmed, giving an incidence of 6.05/10(5) per annum (age specific population) (95% Cl, 5.2-6.9). Acute promyelocytic leukaemia was rare. Erythroleukaemia, monocytic leukaemia and AML with trilineage myelodysplasia were more common than in younger patients. Karyotypic abnormalities classically associated with response to therapy were present in only six of 91 patients where cytogenetic data was available. Treatment was at the discretion of the physician in charge: if given, specific treatment was recorded and clinical outcome assessed. Only 84 (42%) of patients received treatment with curative intent. Forty-four of 84 achieved a complete remission, usually of brief duration. A normal karyotype in leukaemic cells was associated with a survival advantage in this group (p < 0.05). Actuarial overall survival at 4 years for the entire group was 2.5%. Even with aggressive treatment, the outcome is poor. The pattern of disease and its lack of response to conventional treatment would support the hypothesis that AML in the elderly may differ biologically from that observed in younger patients. Karyotyping appears to predict those patients likely to benefit from intensive therapy and decisions about management in otherwise fit patients should, if possible, be delayed until a result is obtained. Every effort should be made to give such patients optimal treatment. However, most patients are unsuitable for aggressive treatment and, since long-term survival is rare, cure should not be offered as an inducement to accept such treatment and improving quality of life outside hospital should be the aim of treatment in this group.

Evaluation of the impact of allogenic transplant in first remission on an unselected population of patients with acute myeloid leukaemia aged 15-55 years. The Northern Regional Haematology Group.

The aim of this study was to collect prospectively unselected, population-based data on young adults with acute myeloid leukaemia (AML) over a 9-year period and to evaluate the impact on survival of the introduction of allogeneic transplantation performed in first remission. The population within the Northern Region of England is 3.09 million. During the study period a total of 149 de novo patients between 15 and 55 years old presented. The incidence of AML was 0.79 per 10(5) (age-specific population) in the 15-24-year-old group, 0.85 per 10(5) in the group 25-39 years old and 1.35 per 10(5) in the 40-55-year-old group. Remission induction success varied with age (74% for patients < 40 years and 58% for patients 40-55 years). In the 15-40 year old group 28 patients had an HLA-matched donor, 22 patients had a transplant (one syngeneic) and 24 patients in the 15-40-year-old group in remission at 6 months did not have a transplant. The allogeneic group < 40 years old had an event-free survival (EFS) at 4 years of 62%, whereas patients of the same age who received chemotherapy alone had an EFS at 4 years of 24%. A small heterogeneous group of 14 patients who had intensification with autotransplant are not included in this analysis. The population study approach demonstrates the difficulties of introducing uniform treatment strategy in this disease group. The study confirms the view that allogeneic transplant in first remission in the 15-40-year-old group is the treatment of choice. Unfortunately the overall impact of transplant on the population is not great since only 22 of 149 patients (14%) were able to receive an allograft in first remission.

Edinburgh drug users: are they injecting and sharing less?

OBJECTIVE: To describe epidemiological trends in injecting and equipment sharing among a sample drawn from a drug-using population with a high rate of HIV infection. DESIGN: A structured interview was administered prior to treatment to cross-sectional samples of drug users over the period 1988-1991. Reports of injecting, sharing and HIV infection were compared annually. SETTING: Lothian Health Board's Community Drug Problems Service is a secondary level service offering harm reduction and treatment of dependency. PARTICIPANTS: A total of 734 consecutively referred drug users resident in Edinburgh. Re-referrals in the same calendar year were excluded. MEASURES: History of injecting and sharing, recent injecting and sharing, HIV testing history, drugs used in previous month and substitute prescription status. RESULTS: Large reductions in the frequency of injecting were found over the 4 years even among those who were not receiving oral substitutes. More participants in latter years were receiving prescriptions combining opioids and benzodiazepines. Fewer of those interviewed latterly had ever shared injecting equipment. Among recent injectors just as many share equipment as previously. HIV prevalence did not vary significantly over the period. An HIV prevalence of 19% was reported among recent injectors. CONCLUSIONS: Edinburgh's drug users are engaging in far safer drug-taking behaviour than previously. Levels of HIV in this population suggest that the epidemic is being contained. A small number persist in high risk drug-related activities. Further investigation of the characteristics of these individuals and the need to develop novel methods of influencing their behaviour are recommended.

Toxicity of single-day high-dose vincristine, melphalan, etoposide and carboplatin consolidation with autologous bone marrow rescue in advanced neuroblastoma.

16 unselected patients with advanced neuroblastoma were given high-dose consolidation chemotherapy with vincristine, melphalan, etoposide and carboplatin over 5 h followed by autologous bone marrow rescue. 3 patients died from treatment-related toxicity, 2 from disease, 1 is alive with disease and 10 are alive and disease-free a median of 12.5 months (range 2-38 months) after bone marrow rescue. All had bone marrow toxicity, most mucositis and 6 had seizures. Renal failure was unexpectedly severe. In the last 3 patients, administration of carboplatin was delayed by 18 h in an attempt to reduce renal damage. The results show that this regimen produces significant morbidity and has a high mortality. Although the overall outcome is encouraging, too few patients have been studied to gauge its efficacy. Whether such aggressive consolidation is necessary in heavily pretreated children with neuroblastoma remains unknown.

High-dose rapid schedule chemotherapy for disseminated neuroblastoma.

In a high-dose schedule for disseminated neuroblastoma, eight courses of chemotherapy were administered every 10 days, regardless of myelosuppression, to eradicate tumour cells rapidly and reduce emergence of drug-resistant clones. Relatively non-myelotoxic vincristine and cisplatin were alternated with high-dose cisplatin-etoposide and cyclophosphamide-etoposide. Of 12 evaluable patients, there were 1 complete (CR), 3 very good partial (VGPR), 5 partial (PR) and 3 mixed responses (MR) 100 days after starting treatment. 6 out of 9 achieved a bone marrow CR at 40 days. 9 of 11 primary tumours were completely resected, after which 4 patients had CR, 3 VGPR (bone scan alone being abnormal), 4 PR and 1 mixed response (MR). Myelotoxicity was the major adverse effect. The only death was due to fungal infection. Clinically important renal dysfunction occurred in 3 patients. 4 had convulsions and 4 temporary hypertension. This schedule produced a rapid response and its toxicity, though serious, was manageable. Further evaluation is warranted.

Posttransplantation B lymphoblastic leukemia with Burkitt-like features.

BACKGROUND: Posttransplantation Epstein-Barr virus-associated lymphoproliferative disease (PTLPD) occurs as a spectrum of disease ranging from benign, polyclonal, localized lymphoid hyperplasia to malignant, monoclonal, disseminated lymphoma, sometimes involving the bone marrow. To our knowledge, PTLPD has not been previously reported to present as acute lymphoblastic leukemia. METHODS: We report the case of a boy who developed PTLPD in the form of acute lymphoblastic leukemia 6 years after cardiac transplantation. He had greater than 90% bone marrow invasion by Epstein-Barr virus-positive B lymphoblasts with Burkitt-like features and a t(8;14) translocation. RESULTS: He was successfully treated with combination chemotherapy but unfortunately died, 6 months after completing treatment, from ischemic heart disease. CONCLUSIONS: B lymphoblastic leukemia may occur as a manifestation of PTLPD and should be included in the classification of these diseases. Bone marrow examination should be an essential part of the investigation of patients suspected of having PTLPD.

Immunopathology of early graft-versus-host disease--a prospective study of skin, rectum, and peripheral blood in allogeneic and autologous bone marrow transplant recipients.

The immunopathological appearances of skin and rectum in 64 autologous and allogeneic recipients were determined before and after bone marrow transplantation. Patients who developed acute graft-versus-host disease were biopsied as soon as a clinical diagnosis was made. At the same time peripheral blood samples were collected for comparative analysis. Immunohistological and morphometric techniques were employed using a panel of monoclonal antibodies to T lymphocytes and subsets, B lymphocytes, natural killer cells, macrophages, and Langerhans cells. A reduction in the CD4/CD8 ratio after BMT was seen in skin and rectal biopsies from both autologous and allogeneic recipients with or without GVHD. The same pattern was observed in blood samples taken at the same time. Langerhans cells were reduced in the skin in all patients after BMT, probably by the conditioning regimen. Only a few cells expressing activation or natural killer cell markers were present and there were no changes observed in the macrophage population. This study has provided no evidence to implicate either CD4- or CD8-positive T lymphocytes as the initiators of the cellular damage in acute GVHD. The distribution of lymphocyte subsets in the blood was similar to that in the tissues, suggesting that the tissue changes reflect the pattern of lymphocyte repopulation after BMT and may have little bearing on the pathogenesis of GVHD.

De novo Ph negative T-cell lymphoblastic leukaemia associated with bcr gene rearrangement.

One case of de novo Ph-negative T-cell acute lymphoblastic leukaemia has been found to have a classical breakpoint cluster region (bcr) rearrangement of the type seen in chronic granulocytic leukaemia. There were no haematological features to suggest a previous chronic phase. This case represents the first report of this rearrangement in Ph negative acute T-lymphoblastic leukaemia at presentation. The implications for various therapeutic options in such patients are discussed.

Skin explant culture as a model for cutaneous graft-versus-host disease in humans.

An in vitro skin explant model for graft-versus-host disease (GVHD) in humans has been used to study the role of effector T cells in the histological pathogenesis of GVHD. In 11 of 12 experiments clear GVHD changes of grades II-IV were induced in HLA-mismatched skin explants cultured with allogeneic T cells sensitized by in vitro mixed lymphocyte culture. The role of effector T cells was investigated by comparing results before and after removal of CD3 positive cells, and CD4 positive and CD8 positive T cell-subsets by antibody and complement cytolysis from responder populations. Only total removal of CD3 positive T cells prevented histopathological lesions of GVHD in the skin biopsy specimens. The results also demonstrated that the CD4 positive population caused the greatest degree of GVHD in vitro in skin biopsy specimens and direct infiltration into skin by cells is not required for changes to become evident. These results confirm the early results on animal models and demonstrate the use of the skin explant model as a tool for studying the biology of GVHD in humans.

In vitro T cell depletion using Campath 1M for mismatched BMT for severe combined immunodeficiency (SCID).

Bone marrow transplantation is the only curative treatment for children with severe combined immunodeficiency (SCID). In the absence of an HLA-identical sibling, haploidentical parental donor marrow can be used provided it is depleted of T cells to prevent otherwise inevitable GVHD. Campath 1M has been successfully used for this procedure in several centres. In our centre 17 SCID patients plus one with combined immunodeficiency (CID) were transplanted with Campath 1M T cell-depleted bone marrow. Progenitor cell recovery, before and after T cell depletion, was monitored using granulocyte-macrophage colony-forming cell assays (GMCFU) and CD34 analysis. The numbers of GMCFU/kg transplanted correlated with engraftment and survival post-transplant and monitoring CD34+ cell numbers in the T cell-depleted marrow pretransplant may be an additional indicator of successful engraftment. Use of a buffy coat marrow preparation with restriction of the number of T cells to < 5 x 10(5)/kg was associated with graft failure in four and death in five of eight children, probably because too few stem cells were infused. T cell depletion of a mononuclear cell preparation of donor marrow with no arbitrary ceiling of infused T cells is highly effective at preventing clinically important GVHD and cured nine out of 10 children transplanted with such material.

Congenital sideroblastic anaemia in two girls.

Transfusion dependent congenital sideroblastic anaemia occurred in infancy in two unrelated girls. One girl developed early organ failure which was not prevented by standard chelation treatment. The combination of modest iron burden and putative intrinsic mitochondrial dysfunction could have accounted for the clinical picture. The other girl remained well, receiving regular transfusion and standard chelation treatment. She had normal liver function and no other evidence of organ damage. The syndrome is unlikely to be due to extreme lyonisation in carriers of the usual X-linked condition. The contrasting clinical patterns seen in these two patients suggest that transfusion dependent congenital sideroblastic anaemia may comprise a heterogeneous group of disorders. It is suggested that such children be carefully monitored for evidence of increasing iron overload so that organ damage can be prevented.

Bone marrow fibrosis in childhood acute lymphoblastic leukaemia.

Bone marrow trephine biopsy specimens were obtained at diagnosis from 63 of 76 consecutively presenting children with acute lymphoblastic leukaemia (ALL). The association between marrow fibrosis and presenting features, including immunophenotype, was analysed. Reticulin was increased in 45 of 56 cases in which blasts expressed B lineage markers, but in only one of seven with T-ALL. A weak association was also found between marrow fibrosis and splenomegaly in those with common ALL. Marrow fibrosis is apparently associated with some examples of ALL of B cell lineage, but precisely which subtypes and whether the phenomenon is clinically important remain to be determined.

Central review of bone marrow biopsy specimens from patients with neuroblastoma.

In order to achieve some uniformity in histological detection of bone marrow infiltration by neuroblastoma and to provide a measure of variation in histological opinions, sections from 712 evaluable trephine biopsy cores from children in a European Neuroblastoma Study Group (ENSG) study were reviewed centrally. Biopsy specimens were graded as tumour positive or negative. Discordance between local and central review opinions was found in 5% of specimens. Only five of 165 children at presentation and nine of 256 re-staging procedures in 126 children, affecting one child each, had their diagnosis upgraded to positive. In six re-staging procedures, affecting one child each, the diagnosis was downgraded. The low discordance rate is encouraging and substantially less important than previously documented difficulties in obtaining adequate specimens.

Distinction between aleukaemic prodrome of childhood acute lymphoblastic leukaemia and aplastic anaemia.

AIMS: To document the features of the so-called aplastic presentation of childhood acute lymphoblastic leukaemia (ALL) and to determine whether this prodrome can be distinguished from aplasia. METHODS: The peripheral blood and bone marrow appearances of all cases of childhood ALL presenting in one health region of England in 13 years and eight months were reviewed. All cases presenting with cytopenia without circulating blasts and marrow aspirates with no infiltrate of blasts were studied in detail. RESULTS: Four of 305 (1.3%) children presented in this way. All four had reticulin fibrosis and increased cellularity in all or part of the marrow biopsy specimen. All were girls. Three had common and one surface membrane immunoglobulin positive ALL. Reassessment of this prodrome, by combining the features of four previously reported series of similar cases with the present one, highlighted the female preponderance (19 of 22 cases), bone marrow fibrosis (10 of 11 evaluable cases), prominent bone marrow lymphocytes (14 of 22 cases) and temporary recovery (all 12 evaluable cases). Six of 14 evaluable cases had bone marrow biopsy specimen appearances of apparently uniform hypocellularity, but only one of these did not have fibrosis. CONCLUSIONS: If, in addition to an aspirate, a bone marrow trephine biopsy is carried out the prodrome can be distinguished from aplasia in most cases. The similarity of this prodrome to aplastic anaemia is merely superficial. Clinicians and morphologists may fail to appreciate the implications of this mode of presentation if the term "aplastic" continues to be used to describe this aleukaemic prodrome of ALL.