Diffuse large B cell lymphoma (DLBCL) in patients older than 65 years: analysis of 3 year Real World data of practice patterns and outcomes in England

BACKGROUND

We wished to examine treatment and outcome patterns in older diffuse large B-cell lymphoma (DLBCL) patients, with a focus on the effect of route-to-diagnosis to outcome.

METHODS

Data were extracted from Public Health England's National Cancer Registration and Analysis Service between 2013 and 2015 included route-to-diagnosis, disease characteristics and survival for 9186 patients ≥65 years. Systemic Anti-Cancer Therapy data identified front-line regimens, cycles and doses.

RESULTS

Route-to-diagnosis were emergency (34%), NHS urgent cancer pathway (rapid haemato-oncologist review <2 weeks), (29%) and standard GP referral (25%). The most common regimen was R-CHOP (n = 4392). 313 patients received R-miniCHOP (7% of R-CHOP). For all patients, 3-year overall survival (OS) for 65-79 years was 57% and for ≥80 years was 32%. Three-year OS for R-CHOP-treated patients diagnosed via emergency presentation was 54% (adjusted hazard ratio (HR) 1.63, p < 0.01) and 75% (adjusted HR 0.81, p < 0.01) on the NHS urgent cancer pathway (reference HR:1.00: GP referrals). 3-year OS was 54% for both R-miniCHOP and R-CHOP in ≥80 years.

CONCLUSIONS

Our comprehensive population analysis is the first to show that the NHS urgent cancer pathway is associated with a superior survival after adjusting for multiple confounders. Equivalent survival for R-CHOP and R-mini-CHOP was demonstrated in those ≥80 years.

Audit of a recently introduced stimulus dosing policy in an electroconvulsive therapy clinic

Aims and method

To audit the clinical practice of seizure threshold estimation and subsequent stimulus dose adjustment in the electroconvulsive therapy (ECT) clinic. Case notes of patients who had ECT over a six-month period were audited. Results were discussed at an audit meeting and guidelines and training modified appropriately prior to the second cycle of the audit.

Results

Initial dose titration was poor in the first period, but improved in the second. The majority of patients were insufficiently stimulated after missed seizures in both periods and stimulus doses were not being reduced following prolonged seizures.

Clinical implications

The audit identified the need for continuing supervision of trainees in addition to clear training and guidelines.

Revisiting guidelines for integration of flow cytometry results in the WHO classification of myelodysplastic syndromes-proposal from the International/European LeukemiaNet Working Group for Flow Cytometry in MDS

Definite progress has been made in the exploration of myelodysplastic syndromes (MDS) by flow cytometry (FCM) since the publication of the World Health Organization 2008 classification of myeloid neoplasms. An international working party initiated within the European LeukemiaNet and extended to include members from Australia, Canada, Japan, Taiwan and the United States has, through several workshops, developed and subsequently published consensus recommendations. The latter deal with preanalytical precautions, and propose small and large panels, which allow evaluating immunophenotypic anomalies and calculating myelodysplasia scores. The current paper provides guidelines that strongly recommend the integration of FCM data with other diagnostic tools in the diagnostic work-up of MDS.

Process evaluation of European 'Healthy Stadia' program

Healthy Stadia (HS) is a European public health pilot-program started in 2007 to support sports stadia in promoting the health of people who work and visit sports stadia, as well as inhabitants of the surrounding communities. The aim of this study is to describe the process evaluation of the program, from its beginning in July 2007 to December 2009, in order to assess the feasibility and sustainability of an HS network across Europe. The program involved nine associate partners involved in the coordination of activities at a local level, in the recruitment of stadia, in the development of specific program tasks and in the dissemination of the program at a national level. The activities of associate partners were evaluated through structured questionnaires administered every 6 months. The questionnaire response rate from associate partners was 77.8% for the first and third evaluations and 88.9% for the second and fourth evaluations. According to the evaluation's results, several good practices such as alcohol prevention policies and those supporting people with disabilities were implemented in stadia over the course of the program. Conversely, practices supporting mental health and green transport were generally not achieved. The implemented activities mainly involved staff and visitors. Lack of human and economic resources, especially toward the end of the program, was considered the principal challenge for program development. In conclusion, the process evaluation presented the feasibility of the HS program and the development of health promoting practices in sport stadia over time.

Simple methodology for the therapeutic drug monitoring of the tyrosine kinase inhibitors dasatinib and imatinib

A simple HPLC method has been developed to measure imatinib and N-desmethylimatinib (norimatinib) in plasma or serum at concentrations attained during therapy. Adaptation of this method to LC-MS/MS also allows dasatinib assay. A small sample volume (100 μL HPLC-UV, 50 μL LC-MS/MS) is required and analysis time is <5 min in each case. Detection was by UV (270 nm) or selective reaction monitoring (two transitions per analyte) tandem mass spectrometry. Assay calibration was linear (0.05-10 mg/L imatinib, 0.01-2.0 mg/L norimatinib and 1-200 µg/L dasatinib), with acceptable accuracy (86-114%) and precision (<14% RSD) for both methods. A comparison between whole blood and plasma confirmed that plasma is the preferred sample for imatinib and norimatinib assay. For dasatinib, although whole blood concentrations were slightly higher, plasma is still the preferred sample. Despite considerable variation in the (median, range) plasma imatinib and norimatinib concentrations in patient samples [1.66 (0.02-4.96) and 0.32 (0.01-0.99) mg/L, respectively, N = 104], plasma imatinib was >1 mg/L (suggested target for response) in all but one sample from patients achieving complete molecular response. As to dasatinib, the median (range) plasma dasatinib concentration was 13 (2-143) µg/L (N = 33). More observations are needed to properly assess the potential role of therapeutic drug monitoring in guiding treatment with dasatinib.

Standardization of flow cytometry in myelodysplastic syndromes: a report from an international consortium and the European LeukemiaNet Working Group

Flow cytometry (FC) is increasingly recognized as an important tool in the diagnosis and prognosis of myelodysplastic syndromes (MDS). However, validation of current assays and agreement upon the techniques are prerequisites for its widespread acceptance and application in clinical practice. Therefore, a working group was initiated (Amsterdam, 2008) to discuss and propose standards for FC in MDS. In 2009 and 2010, representatives from 23, mainly European, institutes participated in the second and third European LeukemiaNet (ELN) MDS workshops. In the present report, minimal requirements to analyze dysplasia are refined. The proposed core markers should enable a categorization of FC results in cytopenic patients as 'normal', 'suggestive of', or 'diagnostic of' MDS. An FC report should include a description of validated FC abnormalities such as aberrant marker expression on myeloid progenitors and, furthermore, dysgranulopoiesis and/or dysmonocytopoiesis, if at least two abnormalities are evidenced. The working group is dedicated to initiate further studies to establish robust diagnostic and prognostic FC panels in MDS. An ultimate goal is to refine and improve diagnosis and prognostic scoring systems. Finally, the working group stresses that FC should be part of an integrated diagnosis rather than a separate technique.

Impact of pre-transplant serum ferritin on outcomes of patients with myelodysplastic syndromes or secondary acute myeloid leukaemia receiving reduced intensity conditioning allogeneic haematopoietic stem cell transplantation

We report on a retrospective analysis examining the influence of pre-transplant serum ferritin on transplant outcomes of 99 MDS patients receiving reduced intensity conditioning (RIC) HSCT. The median pre-transplant ferritin value was 1992 ng/ml (range: 6-9580 ng/ml). No patients received iron chelation therapy preceding transplantation. On univariate analysis, there was a strong correlation between a higher pre-transplant serum ferritin (>1500 ng/ml) and a significantly inferior 3-year OS (64.6+/-7.5% vs 39.6+/-7.3%, p=0.01). However, pre-transplant serum ferritin did not influence 3-year TRM (20.2+/-7% vs 27.4+/-7%, p=0.24). There was no difference in infection-related mortality, and incidence of acute or chronic GvHD between cohorts. On multivariate analysis, a raised serum ferritin (HR: 2.00, 95% CI: 0.97-3.57, p=0.03), and the presence of >5% bone marrow blasts at time of transplantation (HR: 2.14, 95% CI: 0.84-4.58, p=0.06) were independent predictors of an inferior overall survival. However, pre-transplant serum ferritin was not a significant predictor of disease-free survival, relapse or TRM. When compared with myeloablative regimens, RIC regimens may attenuate the impact of iron overload related end-organ toxicity. Prospective studies incorporating alternative biomarkers of iron metabolism alongside serum ferritin levels are needed to improve our understanding of the significance of iron overload in MDS patients undergoing allogeneic transplantation.

Effect of atenolol on QTc interval lengthening during hypoglycaemia in type 1 diabetes

AIMS/HYPOTHESIS

Hypoglycaemia is associated with heart rate-corrected QT (QTc) interval lengthening on the ECG; this may be important in the pathogenesis of sudden overnight death in young people with diabetes. Since hypoglycaemic QTc lengthening appears to be mediated through the sympathoadrenal response, we tested the hypothesis that beta1-blockade will prevent these changes in type 1 diabetic patients and so provide a potential therapeutic intervention.

METHODS

We studied eight type 1 diabetic adults without cardiovascular or renal complications. Similar hypoglycaemic clamp studies were performed on two occasions, at least 4 weeks apart, but immediately before one visit subjects received atenolol 100 mg daily for 7 days. Following a 60-min euglycaemic (5 mmol/l) period, blood glucose was lowered over 30 min to 2.5 mmol/l, and held for 60 min. High-resolution ECG was recorded at baseline and at 0, 30 and 60 min during each glycaemic plateau. QT interval was measured using a semiautomated tangent method and QTc was derived from QT using the Fridericia formula.

RESULTS

Mean (SD) baseline QTc was similar at both visits: control 391 (30) ms, post-atenolol 386 (34) ms; (p=0.33). Without atenolol pretreatment, QTc lengthened during hypoglycaemia to a maximum of 448 (34) ms (p<0.001). On atenolol, QTc lengthening was significantly reduced (peak QTc 413 (27) ms; p=0.004 vs control visit).

CONCLUSIONS/INTERPRETATION

Hypoglycaemic QTc lengthening is blunted by atenolol in patients with type 1 diabetes. Selective beta1-blockade may help prevent sudden death, if we can identify those at high risk.

Online orthodontic advice: a protocol for a pilot teledentistry system

A prototype teledentistry service was established that incorporated a PC-based expert system designed to assist in orthodontic cases. It guided the general dental practitioner (GDP) through the assessment of a patient's malocclusion and helped ensure that all relevant clinical observations were made and details recorded. The resulting data file, containing radiographic images and clinical data, was then transferred via the Internet to a dental specialist. The specialist's recommendations were returned by the same route or, where appropriate, a realtime videoconference was conducted. During an eight-month trial, six GDPs referred 158 cases through the teledentistry system; another 24 cases were referred directly to a local consultant. The protocol used during the trial worked satisfactorily. The GDPs found that it was straightforward and covered all aspects of the cases they submitted.

A preliminary communication on whether general dental practitioners have a role in identifying dental patients with mental health problems

OBJECTIVE

To examine whether general dental practitioners regard themselves as having a role in identifying dental patients with mental health problems.

METHOD

Telephone interviews were conducted with, and postal questionnaires were sent to, a random sample (n = 94) of general dental practitioners on Health Authority lists within the Mersey Region. A total of 84 general dental practitioners responded, resulting in an 89% response rate.

RESULTS

The majority of general dental practitioners had encountered patients with mental health problems (78% of interviewees, 56% of questionnaire responders). However, nearly half of the interviewees (46%) do not refer patients with mental health problems. When referrals to dental specialists were made, they tended to be regarding a physical manifestation rather than a psychological one. The majority of interviewees and questionnaire responders (55% and 82% respectively) expressed a 'positive' response to the development of a referral role. Nevertheless, there were some reservations concerning the practicalities of its development and implementation.

CONCLUSION

The majority of general dental practitioners consider a role in identifying patients with possible mental health problems. This role might include, being able to identify patients with undiagnosed mental health problems, and being aware of dental conditions which may be caused by mental health problems. To achieve this, inter-professional co-operation between general dental practitioners and other health professionals requires development.

Hormonal activation of phosphorylase in cockroach fat body trophocytes: A correlation with trans-membrane calcium flux

This study is an investigation of the temporal relationship between transmembrane Ca(2+) fluxes, and glycogen phosphorylase activation in dispersed trophocytes from the fat body of the cockroach, Periplaneta americana. Phosphorylase is maximally activated within 5 min after treating the trophocytes with either of the hypertrehalosemic hormones, Pea-HTH-I and Pea-HTH-II. Activation caused by Pea-HTH-II is sustained for a longer period than that produced by Pea-HTH-I. Chelation of extracellular Ca(2+) with EGTA blocks the activation of phosphorylase by HTH. Similarly, chelation of intracellular Ca(2+) with Quin 2 greatly diminishes the phosphorylase activating effect of both HTHs. The data support the view that an increase in the intracellular Ca(2+ )concentration is required for the activation of phosphorylase and that extracellular Ca(2+) is an essential, although not necessarily sole, source of Ca(2+) for this purpose. Using (45)Ca(2+) to trace the movement of Ca(2+) following a challenge with either Pea-HTH-I or -II, it was shown that (45)Ca(2+)influx nearly doubled during the first 30 s. At this time, the trophocytes begin to expel Ca(2+) at a rate higher than that of untreated cells and this state persists for approximately 4 min. The Ca(2+) fluxes are consistent with its postulated role in the activation of phosphorylase. Arch.

The use of intravenous intermediate dose melphalan and dexamethasone as induction treatment in the management of de novo multiple myeloma

The variable absorption of melphalan from the gastrointestinal tract results in response rates between 40 and 60%. High dose melphalan increases response rates but at the cost of increased morbidity and mortality. We have investigated intravenous intermediate dose melphalan and dexamethasone in the treatment of patients presenting with de novo multiple myeloma with the object of reducing toxicity while preserving an improved response rate compared to oral melphalan and prednisolone. The results show that this treatment can be delivered safely on an outpatient basis in patients up to the age of 78 yr; 82% of patients achieved an objective response and 30% a complete haematological and clinical remission. Median overall survival for the whole group is 37 months.

A survey examining the attitudes of general dental practitioners toward change in undergraduate dental education

AIM

To determine the attitudes of general dental practitioners toward aspects of change in undergraduate dental education.

DESIGN

Descriptive postal survey using a cross-sectional random sample of general dental practitioners administered in 1997.

SUBJECTS

689 general dental practitioners practising in five regions of England with close proximity to a dental school selected by a one in two stratified random sample.

RESULTS

Response rate: 70%. The questionnaire was both valid and reliable with an internal consistency reliability coefficient of 0.84. Responses identified strong support for preparing dental students for the wider role of the dentist and an emphasis toward self-directed learning. Other themes emerging from the investigation included support for learning to work as part of a dental team and for students to have experience of general dental practice early on in the undergraduate course.

CONCLUSIONS

These responses have implications for curriculum design, syllabus, teaching methods, resources and staff development for dental schools in the UK.

Vaccine-specific antibody responses induced by HIV-1 envelope subunit vaccines

The first generation of candidate vaccines to prevent HIV infection consisted of recombinant envelope proteins (Env, gp120, and gp160) derived from a single laboratory strain of HIV, designated IIIB/LAV, but produced with different expression systems. In this study we examined the fine specificity of the human Ab response to each vaccine and compared them to the responses of laboratory workers infected with the same strain of HIV. The best responders from each vaccine protocol were studied and compared. Detailed comparisons of the fine specificity of the Ab response were possible because all immunologic assays were performed using homologous recombinant proteins, peptides, and virus stocks. Although the total amounts of anti-Env Ab were comparable, the groups exhibited significant differences in epitope specificity, avidity, and functional capacity of the Ab response. The data demonstrate that the form of the immunogen (e.g., live virus or recombinant protein) is important in determining the quality of the Ab response. Conclusions are also drawn regarding characteristics of the anti-HIV-neutralizing Ab response. These studies represent one of the most detailed analyses of the human Ab response to any Ag and have implications for the development of vaccines for HIV as well as for other microbial pathogens.

Vaccine-specific antibody responses induced by HIV-1 envelope subunit vaccines

The first generation of candidate vaccines to prevent HIV infection consisted of recombinant envelope proteins (Env, gp120, and gp160) derived from a single laboratory strain of HIV, designated IIIB/LAV, but produced with different expression systems. In this study we examined the fine specificity of the human Ab response to each vaccine and compared them to the responses of laboratory workers infected with the same strain of HIV. The best responders from each vaccine protocol were studied and compared. Detailed comparisons of the fine specificity of the Ab response were possible because all immunologic assays were performed using homologous recombinant proteins, peptides, and virus stocks. Although the total amounts of anti-Env Ab were comparable, the groups exhibited significant differences in epitope specificity, avidity, and functional capacity of the Ab response. The data demonstrate that the form of the immunogen (e.g., live virus or recombinant protein) is important in determining the quality of the Ab response. Conclusions are also drawn regarding characteristics of the anti-HIV-neutralizing Ab response. These studies represent one of the most detailed analyses of the human Ab response to any Ag and have implications for the development of vaccines for HIV as well as for other microbial pathogens.

Translocation (9;17) a novel translocation in acute myeloid leukaemia

We report a case of AML, acute myeloid leukaemia, with a novel translocation involving the short arms of chromosomes 9 and 17. The acute myeloid leukaemia was morphologically classified as FAB subtype M2. A prolonged remission was induced with chemotherapy, followed by a relapse which was associated with the finding of the same translocation.

Leadership issues: health care in the year 2004

The intent of this article is to develop a plausible scenario for health care in the year 2004. We hope to engage the reader in a process that will help discern the exogenous forces that are currently impacting the way that health care organizations do business. By identifying these forces, we can track their development and learn to adapt and change proactively as may be necessary. We also discuss the current and projected trends that are shaping health care delivery. Our theme is that the future of health care is continually being reinvented and that the potential for dealing effectively with the dramatic change that the future is bringing already exists in most health care organizations. The future is only waiting to be reinvented.

Protective efficacy of nonneutralizing monoclonal antibodies in acute infection with murine leukemia virus

We have used an experimental retrovirus infection to study the roles played by different antibodies in resistance to both infection and disease. A molecularly cloned chimeric murine leukemia virus was used to induce acute lethal neurological disease in neonatal mice. A panel of monoclonal antibodies directed against the Gag and Env proteins was tested for protective efficacy. In vitro neutralization assays demonstrated that anti-Env antibodies gave different degrees of neutralization, while no anti-Gag neutralized the virus. In vivo experimental endpoints were onset of clinical signs and premoribund condition. As expected, different anti-Env antibodies demonstrated different degrees of protection which correlated with their neutralizing abilities. Surprisingly, anti-Gag antibodies directed against both p15 (MA protein) and p30 (CA protein) were also protective, significantly delaying the onset of disease. No protection was seen with either of two control antibodies. The protection with anti-Gag was dose related and time dependent and was also produced with Fab fragments. Treatment with anti-Gag did not prevent viremia but resulted in a slight slowing in viremia kinetics and decreased levels of virus in the central nervous systems of mice protected from disease. These data indicate that nonneutralizing antiretroviral antibodies can influence the outcome of retroviral disease. The data also suggest a functional role for cell surface expression of Gag proteins on murine leukemia virus-infected cells.

The preparation of trophocytes from disaggregated fat body of the cockroach (Periplaneta americana)

A method has been developed for disaggregating the fat body of the adult American cockroach, Periplaneta americana, using collagenase. The yield of cells is sensitive to the osmolarity of the dispersing medium and to the age of the cockroaches from which the fat bodies are taken. Trophocytes uncontaminated with other cells were obtained by taking advantage of the low density of these cells which causes them to float to the top of the dispersion medium. In contrast, the mycetocytes and urocytes being denser than the medium sink to the bottom. The trophocytes retain the ability to respond to the synthetic hyperglycaemic hormones, CCI and CCII, as shown by the activation of phosphorylase and the stimulation of trehalose efflux. The trophocytes incorporated leucine into protein secreted by the cells in a time dependent manner.

The organisation and expression of the genes encoding the mitochondrial glycine decarboxylase complex and serine hydroxymethyltransferase in pea (Pisum sativum)

Restriction fragment length polymorphisms have been used to determine the chromosomal location of the genes encoding the glycine decarboxylase complex (GDC) and serine hydroxymethyltransferase (SHMT) of pea leaf mitochondria. The genes encoding the H subunit of GDC and the genes encoding SHMT both show linkage to the classical group I marker i. In addition, the genes for the P protein of GDC show linkage to the classic group I marker a. The genes for the L and T proteins of GDC are linked to one another and are probably situated on the satellite of chromosome 7. The mRNAs encoding the five polypeptides that make up GDC and SHMT are strongly induced when dark-grown etiolated pea seedlings are placed in the light. Similarly, when mature plants are placed in the dark for 48 h, the levels of both GDC protein and SHMT mRNAs decline dramatically and then are induced strongly when these plants are returned to the light. During both treatments a similar pattern of mRNA induction is observed, with the mRNA encoding the P protein of GDC being the most rapidly induced and the mRNA for the H protein the slowest. Whereas during the greening of etiolated seedlings the polypeptides of GDC and SHMT show patterns of accumulation similar to those of the corresponding mRNAs, very little change in the level of the polypeptides is seen when mature plants are placed in the dark and then re-exposed to the light.

Identification and localization of multiple forms of serine hydroxymethyltransferase in pea (Pisum sativum) and characterization of a cDNA encoding a mitochondrial isoform

Serine hydroxymethyltransferase (SHMT) has been purified from the mitochondria of green pea leaves. Activity can be fractionated into two distinct peaks by ion exchange chromatography. While these two forms of the enzyme are immunologically indistinguishable, immunoinhibition experiments show the presence of a distinct non-mitochondrial third form of the enzyme to also be present in green pea leaves. While this mitochondrial form of SHMT is abundant in leaves it is absent from roots, although the two tissues have comparable SHMT activity. An antibody raised to purified mitochondrial SHMT was used to screen a cDNA expression library. The sequence of one of the isolated positive clones contained an open reading frame, which encoded a sequence that matched the amino acid sequence determined from the N terminus of the mature protein. The open reading frame encodes a mature protein of 487 amino acids with a M(r) of 54,000, together with a 27-31 amino acid serine-rich leader sequence, presumably required for mitochondrial targeting. The cDNA hybridizes to a small multigene family of 2-3 genes, which appear to be expressed predominantly in leaves. Comparison of the deduced amino acid sequence with the amino acid sequences of the rabbit mitochondrial and cytoplasmic SHMT, show that pea mitochondrial SHMT is equally similar to both of these enzymes. In addition, the rabbit sequences are more like one another than they are to the pea sequence, suggesting an interesting evolutionary relationship for these proteins.

Major histocompatibility complex genes and susceptibility to systemic lupus erythematosus in southern chinese

OBJECTIVE

To investigate the predisposing role of major histocompatibility complex (MHC) genes to systemic lupus erythematosus (SLE) in a Chinese population.

METHODS

Polymorphism in the HLA-DRB, DQB, complement component C4, and 21-hydroxylase genes was analyzed by restriction fragment length polymorphism analysis and oligonucleotide probing of in vitro-amplified DNA from 88 Chinese patients with SLE and 69 matched control subjects.

RESULTS

HLA-DRw15 and DQw1 were significantly more frequent in patients (corrected P less than 0.006, relative risk 5.2), but none of the 9 sequence variants of DQw1 were increased. The C4A gene deletion usually associated with SLE in Caucasoid and black patients was absent from all Chinese subjects, but possession of other C4 deletions and of DRw15 conferred the greatest risk (relative risk = 8.3).

CONCLUSION

Different MHC haplotypes predispose to lupus in Chinese than in other ethnic groups. Our data suggest that the susceptibility lies at, or telomeric to, the DR locus, and that DRw15 and C4 deletions may act synergistically in conferring disease susceptibility.

Purification and primary amino acid sequence of the L subunit of glycine decarboxylase. Evidence for a single lipoamide dehydrogenase in plant mitochondria

In order to purify the lipoamide dehydrogenase associated with the glycine decarboxylase complex of pea leaf mitochondria, the activity of free lipoamide dehydrogenase has been separated from those of the pyruvate and 2-oxoglutarate dehydrogenase complexes under conditions in which the glycine decarboxylase dissociates into its component subunits. This free lipoamide dehydrogenase which is normally associated with the glycine decarboxylase complex has been further purified and the N-terminal amino acid sequence determined. Positive cDNA clones isolated from both a pea leaf and embryo lambda gt11 expression library using an antibody raised against the purified lipoamide dehydrogenase proved to be the product of a single gene. The amino acid sequence deduced from the open reading frame included a sequence matching that determined directly from the N terminus of the mature protein. The deduced amino acid sequence shows good homology to the sequence of lipoamide dehydrogenase associated with the pyruvate dehydrogenase complex from Escherichia coli, yeast, and humans. The corresponding mRNA is strongly light-induced both in etiolated pea seedlings and in the leaves of mature plants following a period of darkness. The evidence suggests that the mitochondrial enzyme complexes: pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase, and glycine decarboxylase all use the same lipoamide dehydrogenase subunit.

Cloning and characterization of the P subunit of glycine decarboxylase from pea (Pisum sativum)

A pea leaf cDNA library constructed in lambda gt11 was screened with an antibody raised to the P subunit of glycine decarboxylase. One of the positive clones isolated was sequenced and shown to contain an open reading frame, which encoded the entire P subunit polypeptide. Aligning the deduced amino acid sequence with the amino acid sequence determined directly from the NH2 terminus of the mature P subunit shows the presence of a putative 86 amino acid leader sequence, presumably required for import into the mitochondria, and gives a Mr of the mature protein of 105,000. Comparison of this deduced amino acid sequence with the sequence of a pyridoxal phosphate-containing peptide isolated from the P subunit of chicken liver glycine decarboxylase shows remarkable conservation. The P subunit, however, shows little sequence homology with other published amino acid decarboxylases. Expression of the P subunit mRNA shows a pattern very similar to that of the corresponding polypeptide: it is strongly light induced and is expressed at a much higher level in leaves than in other tissues. Southern blot analysis suggests that the P subunit is encoded by a small multigene family.

Fetal and maternal erythropoietin levels in normal pregnancy

In a cross-sectional study of 120 pregnancies undergoing cordocentesis for prenatal diagnosis (n = 90) or elective caesarean section (n = 30), the umbilical cord and maternal venous plasma erythropoietin (Epo) concentrations were measured. Fetal Epo levels increased from a mean of 4 mU/ml at 16 weeks to 13 mU/ml at 40 weeks' gestation. There were no significant associations between fetal plasma Epo concentration and fetal blood gases, haemoglobin concentration, oxygen content or erythroblast count. The maternal plasma Epo concentration (mean = 14 mU/ml, range 1-77 mU/ml) did not change with gestation but was significantly higher than levels in non-pregnant females (mean = 6.6 mU/ml, range 1-25 mU/ml).

Interleukin-5, interleukin-3, and granulocyte-macrophage colony-stimulating factor cross-compete for binding to cell surface receptors on human eosinophils

Human interleukin (IL)-5 receptors were characterized by means of binding studies using bioactive 125I-labeled IL-5. Of purified primary myeloid cells, eosinophils and basophils but not neutrophils or monocytes expressed surface receptors for IL-5. Binding studies showed that eosinophils expressed a single class of high affinity receptors (Ka = 1.2 x 10(10) M-1) with the number of receptors being small (less than 1000 receptors/cell) and varying between individuals. Among several cell lines examined only HL-60 cells showed detectable IL-5 receptors which were small in numbers (200 receptors/cell) and also bound 125I-IL-5 with high affinity. The binding of IL-5 was rapid at 37 degrees C while requiring several hours to reach equilibrium at 4 degrees C. Specificity studies revealed that the two other human eosinophilopoietic cytokines IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited the binding of 125I-IL-5 to eosinophils. No competition was observed by other eosinophil activating or nonactivating cytokines. The inhibition of 125I-IL-5 binding by IL-3 and GM-CSF was partial up to a concentration of competitor of 10(-7) M with GM-CSF consistently being the stronger competitor. Converse experiments using IL-5 as a competitor revealed that this cytokine inhibited the binding of 125I-IL-3 and of 125I-GM-CSF in some but not all the individuals tested, perhaps reflecting eosinophil heterogeneity in vivo. Cross-linking experiments on HL-60 cells demonstrated two IL-5-containing complexes of Mr 150,000 and Mr 80,000 both of which were inhibited by GM-CSF. The competition between IL-5, IL-3, and GM-CSF on the surface of mature eosinophils may represent a unifying mechanism that may help explain the common biological effects of these three eosinophilopoietic cytokines on eosinophil function. This unique pattern of competition may also be beneficial to the host by preventing excessive eosinophil stimulation.

GM-CSF augments the immunosuppressive capacity of neonatal spleen cells in vitro

Addition of exogenous granulocyte-macrophage colony stimulating factor (GM-CSF) to cultures of adult murine spleen cells with sheep red blood cells (SRBC) results in an augmented plaque forming cell (PFC) response. The influence of GM-CSF on the ability of neonatal spleen cells to suppress the anti-SRBC plaque forming response of adult spleen cells was tested by adding GM-CSF to cultures of neonatal and adult spleen cells. The suppressive capacity of the neonatal spleen cells was augmented by exogenous GM-CSF. The augmented suppression of the neonatal spleen cells was dependent on a G-10 adherent population since the addition of GM-CSF to cultures containing G-10 passed neonatal spleen cells resulted in an augmented PFC response and not suppression. Neonatal splenic glass adherent cells were also capable of suppressing the response. Neonatal spleen cells or purified neonatal glass adherent spleen cells cultured in the presence of GM-CSF had markedly increased levels of PGE2 in the culture supernatant. Neonatal spleen cells cultured with GM-CSF had increased numbers of morphologically identifiable macrophages after 48 hr of culture. Both irradiation and G-10 passage of the neonatal spleen diminished the numbers of macrophages formed in response to GM-CSF, and both of these manipulations resulted in reversal of suppression in response to GM-CSF. Thus, the augmented suppressive capacity of neonatal spleen cells in response to GM-CSF is probably mediated by its ability to drive monocyte to macrophage differentiation as well as increase the suppressive capacity of the existing neonatal splenic macrophages by increasing their production of PGE2.

Anticardiolipin antibodies in patients from Malaysia with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is highly prevalent in Malaysia, which has a mixed population of Malays, Chinese, and Indians. A quantitative enzyme linked immunosorbent assay (ELISA) was used to determine anticardiolipin antibody (aCL) levels (total immunoglobulin, IgG, and IgM) in 200 patients with SLE (164 Chinese, 26 Malay, and 10 Indian) attending the University Hospital of Kuala Lumpur, Malaysia, and 103 matched controls. Only 33 (16.5%) of the patients had raised aCL levels; 26 had raised IgG aCL, five IgM aCL, and two both IgG and IgM aCL. There was a low prevalence of raised levels of aCL in the population studied, which was seen in conjunction with a rare occurrence of thrombosis. The classical association of high aCL levels with thrombocytopenia and recurrent abortions was noted, though not with cerebral disease. The low prevalence of aCL in this study population of mixed racial origin contrasts with findings in European patients with SLE and lends support to the influence of local factors, be they genetic or environmental, on the clinical manifestations of this disease.

T-cell interleukin 1 receptor cDNA expressed in Chinese hamster ovary cells regulates functional responses to interleukin 1

We have cloned a cDNA encoding a receptor identical to the native Mr 80,000 glycoprotein that binds interleukin (IL) 1 alpha and -beta in murine T cells. Chinese hamster ovary (CHO) cells transfected with this T-cell IL-1 receptor (IL-1R) [CHO(IL-1R)] cDNA express approximately 100,000 IL-1Rs per cell, compared to the less than 100 receptors present on control CHO cells. For two functional responses to IL-1, prostaglandin synthesis and cytokine secretion, CHO(IL-1R) cells were 1000 times more sensitive to IL-1 alpha than were control CHO cells. Northern blot analysis and antibody precipitation demonstrated that one of the cytokines induced was granulocyte colony-stimulating factor and that mRNA levels for this cytokine were increased in CHO(IL-1R) cells by IL-1 alpha concentrations that had no effect on control cells. To establish the role of the recombinant receptors in signal transduction, an IL-1R cDNA modified by deletion of the predicted cytoplasmic domain was expressed in the CHO cell line termed CHO(IL-1R delta CT). CHO(IL-1R delta CT) cells expressed approximately 100,000 high-affinity IL-1 binding sites per cell, but these cells were less sensitive than control lines to IL-1, as measured by prostaglandin and cytokine release. These results show that the IL-1R cDNA encodes the entire functional receptor and that the cytoplasmic domain is required for signal transduction but not ligand binding.

Pre-ALL and non-A, non-B hepatitis infection

We report a case of acute lymphoblastic leukaemia which presented as hypoplastic anaemia following Non-A, Non-B viral hepatitis infection. The role of infection and the mechanisms involved in the evolution of pre-ALL to overt leukaemia remain speculative. However, it is of practical importance to distinguish pre-ALL from aplastic anaemia and the myelodysplastic syndromes during the early pancytopenic phase to avoid inappropriate management.

Pulmonary tuberculosis complicated by haemophagocytic syndrome and rifampicin-induced tubulointerstitial nephritis

The benign, or infection-associated, haemophagocytic syndrome (IAHS) is a rare bone marrow disorder of macrophage cell proliferation diagnosed most commonly in immune compromised patients who develop herpes type viral infections (Risdall et al. 1979). It has also been reported in association with bacterial infections and rarely with mycobacterial infection (Chandra et al. 1975; Mamoharon & Catovsky 1981; Bultmann et al. 1982). Despite being potentially reversible it may produce a life-threatening pancytopenia (Seligman et al. 1972). We report a further case of the haemophagocytic syndrome associated with Mycobacterium tuberculosis in which thrombocytopenia was the predominant feature. There were unusual features in the clinical presentation and the patient's treatment and recovery were subsequently complicated by rifampicin-induced renal failure.