Prospective study of bone scintigraphy as a staging investigation for oesophageal carcinoma

BACKGROUND

About 10 per cent of patients undergoing radical oesophagectomy for transmural (T3) carcinoma with lymph node involvement (N1) develop symptomatic bone metastases within 12 months of surgery. The aim of this study was to evaluate the introduction of targeted preoperative bone scintigraphy.

METHODS

Of 790 patients with oesophageal carcinoma staged between December 2000 and December 2004, 189 were eligible for potentially curative treatment. (99m)Tc-labelled hydroxymethylene diphosphonate bone scintigraphy was performed in those with stage T3 N1 disease (identified by computed tomography and endoscopic ultrasonography) who were suitable for radical treatment.

RESULTS

A total of 115 patients had bone scintigraphy. The histological diagnosis was adenocarcinoma in 82 patients and squamous cell carcinoma in 33. Bone scintigraphy was normal or showed degenerative changes in 93 patients, and abnormal requiring further investigation in 22. Plain radiography, magnetic resonance imaging and biopsy confirmed the presence of bone metastases in 11 patients (9.6 per cent).

CONCLUSION

Bone is frequently the first site of identifiable distant metastatic spread, and bone scintigraphy is recommended to exclude metastatic disease before radical treatment of advanced oesophageal carcinoma.

DNA fusion vaccines incorporating IL-23 or RANTES for use in immunization against influenza

The incorporation of RANTES or IL-23 into DNA vaccines may improve their immunogenicity by the recruitment and activation of dendritic cells. This may also select for a TH1 response counteracting the TH2 response which can predominate when a DNA vaccine is delivered by gene gun. We have immunized mice with various DNA constructs encoding APR/8/34 influenza virus hemagglutinin (HA), either fused to or separate from, IL-23 or RANTES using a gene gun. Those immunized with IL-23/HA fusion constructs and challenged with influenza 27 weeks post-vaccination, tended to have cleared more virus than those vaccinated with HA DNA. Mice immunized with the RANTES/HA fusion construct produced a mixed TH1/TH2 response whereas in HA-vaccinated mice, a TH2 response predominated. Immunization with a plasmid in which HA and RANTES were under the control of separate promoters, failed to generate a mixed TH1/TH2 response suggesting that enhanced antigen uptake via RANTES receptors may contribute to the mixed immune response generated to the fusion construct. Overall these findings provide further evidence that Type 1 cytokines or chemokines, fused to antigen in a DNA vaccine, can influence the nature and the longevity of the immune response and ultimately, its protective capacity.

Beta-glucosylceramide: a novel method for enhancement of natural killer T lymphoycte plasticity in murine models of immune-mediated disorders

BACKGROUND

beta-Glucosylceramide, a naturally occurring glycolipid, exerts modulatory effects on natural killer T (NKT) lymphocytes.

AIM

To determine whether beta-glucosylceramide can alter NKT function in opposite directions, colitis was induced by intracolonic installation of trinitrobenzenesulphonic acid, and hepatocellular carcinoma (HCC) was induced by transplantation of Hep3B cells.

METHODS

The immunological effect of beta-glucosylceramide was assessed by analysis of intrahepatic and intrasplenic lymphocyte populations, serum cytokines and STAT protein expression.

RESULTS

Administration of beta-glucosylceramide led to alleviation of colitis and to suppression of HCC, manifested by improved survival and decreased tumour volume. The beneficial effects were associated with an opposite immunological effect in the two models: the peripheral:intrahepatic CD4:CD8 lymphocyte ratio increased in the colitis model and decreased in the HCC group. The peripheral:intrahepatic NKT lymphocyte ratio decreased in beta-glucosylceramide-treated mice solely in the HCC model. The effect of beta-glucosylceramide was associated with decreased STAT1 and 4 expression, and with overexpression of STAT6, along with decreased interferon gamma levels in the colitis model, whereas an opposite effect was noted in the HCC model.

CONCLUSIONS

beta-glucosylceramide alleviates immunologically incongruous disorders and may be associated with "fine tuning" of immune responses, by changes in plasticity of NKT lymphocytes.

Location of major histocompatibility complex class II molecules in rafts on dendritic cells enhances the efficiency of T-cell activation and proliferation

The existence of major histocompatibility complex (MHC) class II molecules in lipid rafts has been described in dendritic cells (DC); however, the importance of rafts in T-cell activation has not been clarified. In this study, the distribution of the lipid raft components (CD59 and GM1 ganglioside) in human monocyte-derived DC was investigated. DC had an even distribution of these components at the cell surface. In addition, raft-associated GM1 ganglioside colocalized with cross-linked MHC class II. This implies coaggregation of raft components with these MHC molecules, which may be important in the interaction between T cells and antigen-presenting cells. In studies carried out to investigate the effect of the DC : T-cell interaction on raft distribution, we found a clustering of the lipid raft component CD59 on DC at the synaptic interface, with associated activation of the interacting T cell. In an antigen-specific response between DC and CD4+ T-cell clones, disruption of lipid rafts resulted in inhibition of both CD59 clustering and T-cell activation. This was most pronounced when limiting amounts of cognate peptide were used. Together, these data demonstrate the association of MHC class II with lipid rafts during DC : T-cell interaction and suggest an important role for DC lipid rafts in T-cell activation.

Single blind, randomised, comparative study of the Bug Buster kit and over the counter pediculicide treatments against head lice in the United Kingdom

OBJECTIVE

To compare the effectiveness of the Bug Buster kit with a single treatment of over the counter pediculicides for eliminating head lice.

DESIGN

Single blind, multicentre, randomised, comparative clinical study.

SETTING

Four counties in England and one county in Scotland.

PARTICIPANTS

133 young people aged 2-15 years with head louse infestation: 56 were allocated to the Bug Buster kit and 70 to pediculicide treatment.

INTERVENTIONS

Home use of proprietary pediculicides (organophosphate or pyrethroid) or the Bug Buster kit.

MAIN OUTCOME MEASURE

Presence of head lice 2-4 days after end of treatment: day 5 for the pediculicides and day 15 for the Bug Buster kit.

RESULTS

The cure rate using the Bug Buster kit was significantly greater than that for the pediculicides (57% v 13%; relative risk 4.4, 95% confidence interval 2.3 to 8.5). Number needed to treat for the Bug Buster kit compared with the pediculicides was 2.26.

CONCLUSION

The Bug Buster kit was the most effective over the counter treatment for head louse infestation in the community when compared with pediculicides.

Comparison of different microbial bioassays to assess metal-contaminated soils

These experiments compared the sensitivity of four different types of bioassay over time after five metals were added to a wide range of soils at the maximum concentrations in the European Union Sewage Sludge Directive. Three were chronic assays (most probable number of Rhizobium leguminosarum, soil microbial C and Biolog substrate utilization). The fourth bioassay, an acute biosensor, employed a lux-marked luminescent bacterium (Escherichia coli) in the soil pore water. Five metals were added to 23 different soils as a mixture at Zn = 300, Cd = 3, Pb = 300, Cu = 135, and Ni = 75 mg/kg as nitrate salts and compared with unamended controls. Zinc and Cu were the metals most likely to be toxic at the concentrations used here. In the case of Rhizobium, the number of cells in soil was not affected after 11 d; however, by 818 d the numbers had decreased by four orders of magnitude with increasing concentrations of Zn and Cu in soil solution. Microbial biomass also was not affected after 11 d, but significantly decreased with increased Zn (p < 0.001) and Cu (p < 0.01) in soil solution after 818 d. Toxicity to the soil microbial biomass increased with time, whereas the toxicity to the biosensor remained the same. Biolog substrate utilization profiles were not responsive to the concentrations used here.

A confidential study of deaths after emergency medical admission: issues relating to quality of care

In this retrospective pilot study we examine the feasibility of establishing a confidential enquiry into why some patients die after emergency admission to hospital. After excluding those who died in the first hour or who were admitted for palliative care, pairs of physicians were able to collect quantitative and qualitative data on 200 consecutive deaths. Both physicians reported shortfalls of care in 14 patients and one of the pair in 25 patients whose deaths would not have been the expected outcome. In 25, the shortfalls of care may have contributed to their deaths. Major problems were delays in seeing doctors, inaccurate diagnoses, delays in investigations and initiation of treatment. They occurred mostly in those admitted at night. It is possible that establishing the correct diagnosis and starting appropriate treatment may have been delayed in 64% of the 200 patients. The headline figures appear worse than some previous external assessment studies but this study did concentrate on those in whom problems were more likely. Nevertheless, the frequency is too high to be overlooked. In this feasibility study we have demonstrated that it is practicable for local staff to collect and assess data in hospitals and that the types of problems identified are relevant to anyone planning how to organise emergency care. A larger definitive study should be performed.

Predicting arsenic solubility in contaminated soils using isotopic dilution techniques

An isotopic dilution assay was developed to measure radiolabile As concentration in a diverse range of soils (pH 3.30-7.62; % C = 1.00-6.55). Soils amended with 50 mg of As kg(-1) (as Na2HAsO4 x 7H2O) were incubated for over 800 d in an aerated "microcosm" experiment. After 818 d, radiolabile As ranged from 27 to 57% of total applied As and showed a pH-dependent increase above pH 6. The radiolabile assay was also applied to three sets of soils historically contaminated with sewage sludge or mine-spoil. Results reflected the various geochemical forms in which the arsenic was present. On soils from a sewage disposal facility, radiolabile arsenate ranged from 3 to 60% of total As; mean lability was lower than in the equivalent pH range of the microcosm soils, suggesting occlusion of As into calcium phosphate compounds in the sludge-amended soils. In soils from mining areas in the U.K. and Malaysia, radiolabile As accounted for 0.44-19% of total As. The lowest levels of lability were associated with extremely large As concentrations, up to 17,000 mg kg(-1), from arsenopyrite. Soil pore water was extracted from the microcosm experiment and speciated using "GEOCHEM". The solid<==>solution equilibria of As in the microcosm soils was described by a simple model based on competition between HAsO4(2-) and HPO4(2-) for "labile" adsorption sites.

Use of bacterial biosensors to interpret the toxicity and mixture toxicity of herbicides in freshwater

The dose response relationship between seven commonly used herbicides and four luminescence-based bacterial biosensors was characterised. As herbicide concentration increased the light emitted by the test organism declined in a concentration dependent manner. These dose responses were used to compare the predicted vs. observed response of a biosensor in the presence of multiple contaminants. For the majority of herbicide interactions, the relationship was not additive but primarily antagonistic and sometimes synergistic. These biosensors provide a sensitive test and are able to screen a large volume and wide range of samples with relative rapidity and ease of interpretation. In this study biosensor technology has been successfully applied to interpret the interactive effects of herbicides in freshwater environments.

Soil solution extraction techniques for microbial ecotoxicity testing: a comparative evaluation

The suitability of two different techniques (centrifugation and Rhizon sampler) for obtaining the interstitial pore water of soil (soil solution), integral to the ecotoxicity assessment of metal contaminated soil, were investigated by combining chemical analyses and a luminescence-based microbial biosensor. Two different techniques, centrifugation and Rhizon sampler, were used to extract the soil solution from Insch (a loamy sand) and Boyndie (a sandy loam) soils, which had been amended with different concentrations of Zn and Cd. The concentrations of dissolved organic carbon (DOC), major anions (F- , CI-, NO3, SO4(2-)) and major cations (K+, Mg2+, Ca2+) in the soil solutions varied depending on the extraction technique used. Overall, the concentrations of Zn and Cd were significantly higher in the soil solution extracted using the centrifugation technique compared with that extracted using the Rhizon sampler technique. Furthermore, the differences observed between the two extraction techniques depended on the type of soil from which the solution was being extracted. The luminescence-based biosensor Escherichia coli HB101 pUCD607 was shown to respond to the free metal concentrations in the soil solutions and showed that different toxicities were associated with each soil, depending on the technique used to extract the soil solution. This study highlights the need to characterise the type of extraction technique used to obtain the soil solution for ecotoxicity testing in order that a representative ecotoxicity assessment can be carried out.

Measuring symptom change in patients with Parkinson's disease

BACKGROUND

The 39-item Parkinson's disease questionnaire (PDQ-39) is more sensitive to functional change than other measures of health and disability.

AIM

To determine the ability of this scale to change over time and the concurrent validity of some of its subscales.

METHODS

We assessed a cohort of 67 Parkinson's patients for 18 months, using the PDQ-39, the GHQ-28 general health questionnaire and the Office of Population and Census Surveys disability instrument.

RESULTS

The Office of Population and Census Surveys disability instrument and GHQ-28 recorded no significant change, but the PDQ-39 showed marked changes in levels of functioning. We also analysed changes on the PDQ-39 subscales as well as concurrent validity data for several subscales. This showed concurrent validity with the Beck depression and anxiety inventories, the Barthel index and the Royal Postgraduate Medical School severity scale. There was a high level of concurrent validity for all comparisons except for the Barthel index.

CONCLUSION

The PDQ-39 is a sensitive tool for monitoring change in patients with Parkinson's disease. It has high levels of concurrent validity with established measures of mood and motor function.

Computer-generated correspondence for patients attending an open-access chest pain clinic

AIM

To determine whether general practitioners (GPs) prefer structured computer-generated or standard dictated outpatient clinic letters.

DESIGN

Questionnaire survey of all GPs referring patients to an open-access chest pain clinic at a district general hospital in London. The GPs were asked to compare three twinned examples of structured computer-generated and unstructured dictated letters.

RESULTS

Of 93 respondents (response rate 77.5%), 75 (80.6%) preferred the computer-generated letter and 16 (17.2%) preferred the dictated letter (p < 0.0005). The preferred features of the computer-generated letter were its clear presentation, subheadings, and concise information. The computer-generated letter scored significantly higher than the dictated letter: for clarity, mean 8.2 vs 6.5 (p < 0.0005); content, mean 8.5 vs 6.9 (p < 0.0005); and readability, mean 8.2 vs 6.8 (p < 0.0005). The GPs in the survey considered a mean delay of 3.4 days to be acceptable for receiving the letter from the chest pain clinic.

CONCLUSION

GPs prefer structured computer-generated letters to unstructured dictated letters for patients referred to an open-access chest pain clinic. Computer-generated correspondence allows rapid feedback of information to the referring GP, one of the key requirements of open-access clinics.

The leukocyte/neuron cell surface antigen OX2 binds to a ligand on macrophages

The OX2 membrane glycoprotein contains two immunoglobulin superfamily (IgSF) domains and seems likely to interact with other cell surface proteins. A soluble chimeric protein with the two IgSF domains of OX2 engineered onto domains 3 + 4 of rat CD4 antigen was expressed. To detect possible weak interactions, the chimeric protein was coupled to fluorescent covaspheres to provide a highly avid display of OX2. The OX2 covaspheres bound macrophages but not other cell types. The specificity of the interaction was demonstrated by blocking with Fab fragments of the OX2 monoclonal antibody (mAb). A new mAb, MRC OX88, was raised against macrophages which also blocked the interaction and presumably recognizes the ligand. The epitope for the MRC OX2 mAb and a site for ligand binding were mapped to domain 1 by site-directed mutagenesis. The OX2 antigen is present on thymocytes, some lymphocytes, neurons and endothelial cells; thus, it has the potential to mediate interactions between these cell types and macrophages.

The use of administrative data to risk-stratify asthmatic patients

In this article, a simple methodology to risk-stratify asthmatics is presented and validated. Such a model can be used to identify those high risk and more severely ill asthmatics who could benefit the most from case management and increased educational efforts. Using logistic regression, the model was created to predict the probability of an asthma-related admission among all asthmatics who were members of a large HMO during calendar year 1994 (N = 54,573). The model used data from pharmacy, laboratory, and specialist claims, as well as encounter and demographic data available in U.S. Healthcare's administrative database. A member's prior asthma-specific utilization patterns, pharmaceutically determined severity of illness, and length of enrollment in the managed care organization had the most influence on the equation. A cross-validation of the model confirms how administrative data can be used to accurately risk-stratify those with a chronic disease. Finally, some additional research possibilities associated with the identification of high risk subscribers using only administrative data are outlined.

Clinical hypertension in Native Americans: a comparison of 1987 and 1992 rates from ambulatory care data

THE AUTHORS EXAMINED THE PREVALENCE of clinically diagnosed hypertension among all American Indian and Alaska Native outpatients served in Indian Health Service (IHS) facilities in fiscal year 1992, and compared these rates with a similar analysis done in 1987. In this report they provided data on that analysis as well as on the association between hypertension and diabetes. The 1992 overall estimated age-adjusted prevalence of clinically diagnosed hypertension in adults older than age 15 was 10.4%, compared with 10.9% in 1987, a small but significant decrease. Considerable variation exists in hypertension prevalence rates in American Indian communities as analyzed by IHS service area. This report represents an attempt to use ambulatory patient care data to demonstrate a means for ongoing surveillance of a chronic disease for the entire service population of the IHS. This comprehensive data set represents approximately 60% of the entire U.S. American Indian and Alaska Native population. Based on the ongoing nature of this ambulatory patient care data system, this model for hypertension surveillance permits a unique opportunity for longitudinal evaluation of quality improvement efforts for the American Indian and Alaska Native populations served by the IHS.

A sensitive assay for detecting low-affinity interactions at the cell surface reveals no additional ligands for the adhesion pair rat CD2 and CD48

The ligand for the T cell antigen CD2 is CD48 in rodents, but CD58 in humans. The extracellular parts of these three antigens are structurally related in that all contain two immunoglobulin superfamily (IgSF) domains. There have been reports of alternative ligands for CD2 in the human, but not so far in rodents. We describe the analysis of ligands for rat CD2 and CD48 using fluorescent beads capable of displaying a high ligand density and detecting low-affinity interactions like that of CD2 with CD48 (Kd = 60-90 microM). Monovalent chimeric proteins containing the two IgSF domains of rat CD48 or CD2 and domains 3 and 4 of rat CD4 (CD4d3+4) were anchored to fluorescent covaspheres via a CD4 monoclonal antibody (mAb) with the CD48 or CD2 domains available for ligand binding. Multivalent CD48-CD4d3+4 covaspheres gave strong specific binding to rat CD2 expressed on the surface of transfected Jurkat cells. CD48-CD4d3+4 was compared with CD48-IgG and CD48-IgM as tools for detecting binding at the cell surface. Soluble divalent CD48-IgG and decavalent CD48-IgM bound to soluble CD2 with a Koff of around 10(-3) s-1 as determined using a BIAcore biosensor. However, binding to cells by CD48-IgG and CD48-IgM was only detectable when they were immobilized on covaspheres and represented no increase in sensitivity over CD48-CD4 covaspheres when tested for binding to cells expressing high and low levels of CD2. CD48-CD4d3+4 covaspheres only bound to rat cells expressing CD2. In the reverse orientation, bindign of CD2-CD4d3+4 covaspheres was dependent on expression of CD48. Pre-incubation of cells with CD2 or CD48 mAb abolished all binding of CD48-CD4d3+4 or CD2-CD4d3+4, respectively. The data provide no evidence for an alternative ligand for rat CD2 or CD48.

Mating in the monogamous male: behavioral consequences

In monogamous mammals, males typically show selective affiliation with a single mate, high levels of paternal care, and aggression towards conspecifics to protect male and offspring. We have previously described how selective aggression and affiliation increase after mating in the male prairie vole, Microtus ochrogaster. The current studies further explored the behavioral changes that follow mating in the male of this species. The first set of experiments tested males on several behavioral measures after 24 h of either mating, social (but not sexual) exposure, or no social contact. After 24 h of mating, but not after the other two conditions, aggression and affiliation (partner preference) increased as previously reported. In addition, mated animals showed increased exploration of the open arms of a plus maze, consistent with decreased fearfulness. There were no group differences in paternal behavior (which was high in all three conditions) or analgesia (assessed by tail flick latency). To determine the minimum amount of mating necessary for the induction of aggression, males were tested in a resident-intruder paradigm after 1,6, or 24 h of mating. Although 1 h of mating was associated with a transient increase in the frequency of threats and attacks, the full spectrum of enduring aggression was observed only in the males given 24 h of mating. In a final experiment, the behavioral consequences of mating were studied in males of the closely related montane vole (Microtus montanus) which does not pair bond. Males of this nonmonogamous vole species did not show increased aggression, partner preference, or alterations in plus maze exploration following 24 h of mating. These results demonstrate the importance of prolonged mating for the induction of pair bonding in the monogamous male and they suggest that increases in aggression and affiliation are associated with decreased fearfulness in pair bonded males.