The immunogenicity of MUC1 peptides and fusion protein

Mucin 1 (MUC1) is highly expressed in breast cancer, has an ubiquitous distribution and, due to altered glycosylation, peptides within the VNTR are exposed. These peptides are the target for anti-MUC1 antibodies, which give a differential reaction on cancer compared with normal tissue. The amino acids, APDTR or adjacent amino acids, are highly immunogenic in mice for antibody production (after immunisation with either breast cancer cells, human milk fat globule (HMFG) or the VNTR peptide). In addition, human studies show that this region of the MUC1 VNTR functions as target epitopes for cytotoxic T cells. We have performed preclinical and clinical studies to examine the immune responses to MUC1 in mice and humans: (a) MUC1+ 3T3 or P815+ 3T3 cells in syngeneic mice are rejected, with the generation of both cytotoxic T lymphocyte (CTL) and DTH responses and a weak antibody response and a weak antibody responses; this type of immunity gives rise to total resistance to re-challenge with high doses of these tumors; (b) immunisation with peptides (VNTR x 2), a fusion protein (VNTR x 5), or HMFG leads to no CTLs, DTH, good antibody production and weak tumour protection (to 10(6) cells, but not 5 x 10(6) cells) (possibly a TH2 type response); (c) immunisation with mannan-fusion protein (MFP) gives rise to good protection (resistance to 50 x 10(6) cells), CTL and DTH responses and weak antibody responses (possibly a TH1 type response, similar in magnitude to that obtained after tumor rejection); (d) established tumors can be rapidly rejected by delayed treatment of MFP; (e) the CTL responses are MHC restricted (in contrast to the human studies); (f) APDTR appears not to be the T cell reactive epitope in mice. On the basis of these findings, two clinical trials are in progress: (a) VNTR x 2 (diphtheria toxoid) which gives rise to some T cell proliferation, DTH and antibody responses in some patients and (b) an MFP trial. The ability to alter the immune response towards cellular immunity with mannan or to humoral immunity with peptides, allows the immune response to be selectively manipulated.

A phase II trial of zeniplatin in metastatic melanoma

A third-generation platinum analogue, zeniplatin, was administered at a dose of 145 mg/m2 intravenously over 60-90 minutes every 21 days as the initial chemotherapy to 21 patients with metastatic melanoma. Prehydration and mannitol diuresis was introduced after the first 7 patients. There were 17 males and 4 females. The median age was 52 (range: 29-81). ECOG performance status was 0 in 10 patients, 1 in 8 patients and 2 in 3 patients. Major disease sites were lymph nodes, skin, lung, liver, and bone. Patients received a median of 2 cycles (range: 1-7). Two patients achieved partial responses. One with nodal disease progressed after 166 days and the other with buccal mucosal disease after 142 days. A third patient showed partial regression of nodal disease but developed cerebral metastases. Gastrointestinal toxicity included WHO grade 3 vomiting in 8 patients and nausea in 2. Antiemetics were used, but ondansetron was not available. WHO grade 3 hematologic toxicities included neutropenia in 8 patients and anemia and thrombocytopenia in 1 patient. Thrombocytosis was seen in 35% of courses. Dosage reduction was required in 15% of courses and escalation in 5% of courses. Three patients developed phlebitis related to the infusion. One patient developed a reversible rise in serum creatinine, but, unlike other studies, no severe nephrotoxicity was reported. Zeniplatin demonstrated only modest activity in melanoma with significant gastrointestinal and hematologic toxicity.

Aneuploidy in late-step spermatids of mice detected by two-chromosome fluorescence in situ hybridization

A multicolor procedure employing fluorescence in situ hybridization is described for detecting chromosomal domains and germinal aneuploidy in late-step spermatids in mice using DNA probes specific for repetitive sequences near the centromeres of chromosomes 8 and X. These probes were nick-translated with biotin- or digoxigenin-labeled nucleotides, and were detected with FITC or rhodamine. Probe and hybridization specificities were confirmed using metaphase chromosomes from spleen and bone marrow cells as well as from primary and secondary spermatocytes. Late-step spermatids, identified in testicular preparations by their hooked shape, yielded compact fluorescence domains in approximately 50% and > 99% of cells when hybridized with probes for chromosomes X and 8, respectively. In a survey of > 80,000 late-step spermatids from 8 healthy young adult C57BL/6 or B6C3F1 mice, approximately 3/10,000 spermatids had fluorescence phenotypes indicative of X-X or 8-8 hyperhaploidy. These frequencies are consistent with published frequencies of aneuploidy in meiotic metaphase II and first cleavage metaphases of the mouse, providing preliminary validation of sperm hybridization for the detection of aneuploidy. No significant animal or strain differences were observed. In addition, the hyperhaploidy frequencies for murine spermatids were indistinguishable for those for sperm from healthy men obtained by a similar hybridization procedure. These procedures for detecting aneuploid male gametes are examples of "bridging biomarkers" between human and animal studies. They have promising applications for investigations of the genetic, reproductive, and toxicological factors leading to abnormal reproductive outcomes of paternal origin.

A phase III study of accelerated radiotherapy with and without carboplatin in nonsmall cell lung cancer: an interim toxicity analysis of the first 100 patients

PURPOSE

In 1989 we initiated a multicenter randomized trial to determine if accelerated radiotherapy with or without concurrent carboplatin improves local control and survival in patients with limited nonsmall cell lung cancer. This interim analysis was performed on the first 100 patients to determine whether the toxicity of the four treatment arms is acceptable.

METHODS AND MATERIALS

One hundred patients with limited nonsmall cell lung cancer have been randomized to receive one of four treatments: arm I, radiotherapy 60 Gray (Gy) in 30 fractions in 6 weeks; arm II, accelerated radiotherapy 60 Gy in 30 fractions in 3 weeks; arm III, radiotherapy as in arm I plus carboplatin 350 mg/m2 during weeks 1 and 5 of radiotherapy; arm IV, radiotherapy as in arm II plus carboplatin 350 mg/m2 during week 1. Survival was measured for the group as a whole and treatment-related toxicities in the four arms were compared.

RESULTS

The estimated median survival for all 100 patients was 17.1 months with 33% estimated survival at 2 years. The major toxicities were hematologic and esophageal. Patients receiving carboplatin had more neutropenia (p < 0.0001) and thrombocytopenia (p = 0.002) than patients receiving radiotherapy alone, and this was most marked in patients on arm III. Both carboplatin and accelerated radiotherapy separately caused more severe esophagitis when compared to conventional radiotherapy alone (p = 0.011 and p = 0.0017, respectively). Esophagitis was more prolonged in patients having accelerated radiotherapy (p < 0.0001, median duration 3.2 months compared with 1.4 months for patients receiving conventional fractionation). Six patients (23%) treated on arm II have required dilatation of esophageal stricture, one dying with a laryngo-esophageal fistula.

CONCLUSION

In patients receiving radiotherapy for unresectable lung cancer, overall treatment time can be halved and carboplatin administered concurrently with increased but acceptable esophageal and hematologic toxicity.

Estradiol enhances brain glucose uptake in ovariectomized rats

This study was designed to investigate the effects of 17 beta-estradiol benzoate (E2B) on brain glucose uptake and transport across the blood-brain barrier (BBB). Both a time- and dose-response evaluation of the effect of E2B on glucose uptake in the central nervous system (CNS) were conducted. E2B, in doses ranging from 1 to 100 micrograms/kg body weight, was injected subcutaneously at 2 to 24 h prior to evaluation. The 4-h time point and 10 micrograms/kg dose of E2B produced the most widespread increases in glucose uptake. Six regions responded to E2B with elevated glucose uptake by as much as 120% when compared to oil-treated controls. We then evaluated the effects of E2B on transport of glucose across the BBB. E2B significantly increased the extraction of labeled sugar across the BBB by 40% without affecting extraction of the internal standard. Collectively, these studies indicate that physiological levels of estradiol (E2) may play an important role in modulating cerebral glucose homeostasis.

Prevalence of asthma and wheeze in Hong Kong schoolchildren: an international comparative study

Comparison of asthma prevalence between populations is difficult because of lack of uniformity of methodology and agreement on the definition. This study aims to determine and compare the prevalence of wheeze and respiratory symptoms in Hong Kong schoolchildren with that in Melbourne children by using identical questionnaires. Schools were randomly selected in different regions of Hong Kong and three age groups (7, 12 and 15 yrs) were chosen for the study. The Chinese version of the questionnaire used in a recent Melbourne survey was distributed to children for completion by their parents. A total of 1,800 questionnaires was issued and 1,689 returned (response rate = 94%). The prevalence of wheeze in the past 12 months was 7 (5.1-8.0), 5 (3.0-6.7) and 4 (1.7-5.6) % for 7, 12 and 15 year olds, respectively. The prevalence of a history of asthma in the respective age groups was 10 (7.1-12.9), 8 (7.5-9.2) and 7 (5.0-9.6) %, respectively. Whilst a history of wheeze ever was more common in boys than in girls and 12 yr olds (14% vs 5%), wheeze in the past 12 months was more common in boys than in girls aged 7 yrs (9 vs 4%). We conclude that the prevalence of wheeze and asthma in school children was low in Hong Kong compared to Melbourne. Environmental differences between the two regions may be important in the pathogenesis.

Dynamic spin-echo imaging: theoretical assessment and implementation

A spin-echo method for obtaining dynamic magnetic resonance (MR) images is described. The method combines the RARE (rapid acquisition with relaxation enhancement) pulse sequence with a data acquisition scheme in which only a centric fraction of the raw data is sampled to increase the time resolution of the dynamic images. The missing high-resolution data are supplied from reference images. By these means, an effective time resolution of about 10 seconds per image is achieved, which is suitable for diagnostic assessment of contrast enhancement procedures. A promising clinical application is contrast-enhanced MR imaging of the pituitary. Although the resolution of small objects in this size range is potentially degraded, this shortcoming is compensated for with use of variable refocusing flip angles. In the context of pituitary imaging, the centric 30%-40% of the raw data is shown to be the optimal fraction to acquire for the low-resolution dynamic images. Ten patients with previous history of pituitary disease have been imaged with dynamic and conventional spin-echo techniques. In six of these patients, an equivalent diagnosis was reached with dynamic and conventional images, while in two, only the dynamic images showed the lesion; in the final two patients, only the conventional images showed the lesion.

Prevalence of asthma and wheeze in Hong Kong schoolchildren: an international comparative study

Comparison of asthma prevalence between populations is difficult because of lack of uniformity of methodology and agreement on the definition. This study aims to determine and compare the prevalence of wheeze and respiratory symptoms in Hong Kong schoolchildren with that in Melbourne children by using identical questionnaires. Schools were randomly selected in different regions of Hong Kong and three age groups (7, 12 and 15 yrs) were chosen for the study. The Chinese version of the questionnaire used in a recent Melbourne survey was distributed to children for completion by their parents. A total of 1,800 questionnaires was issued and 1,689 returned (response rate = 94%). The prevalence of wheeze in the past 12 months was 7 (5.1-8.0), 5 (3.0-6.7) and 4 (1.7-5.6) % for 7, 12 and 15 year olds, respectively. The prevalence of a history of asthma in the respective age groups was 10 (7.1-12.9), 8 (7.5-9.2) and 7 (5.0-9.6) %, respectively. Whilst a history of wheeze ever was more common in boys than in girls and 12 yr olds (14% vs 5%), wheeze in the past 12 months was more common in boys than in girls aged 7 yrs (9 vs 4%). We conclude that the prevalence of wheeze and asthma in school children was low in Hong Kong compared to Melbourne. Environmental differences between the two regions may be important in the pathogenesis.

Filgrastim in patients with chemotherapy-induced febrile neutropenia. A double-blind, placebo-controlled trial

OBJECTIVE

To determine if filgrastim (recombinant human methionyl granulocyte colony-stimulating factor) used in addition to standard inpatient antibiotic therapy accelerated recovery from infection associated with chemotherapy-induced neutropenia.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

Hematology and oncology wards of four teaching hospitals.

PATIENTS

218 patients with cancer who had fever (temperature > 38.2 degrees C) and neutropenia (neutrophil count < 1.0 x 10(9)/L) after chemotherapy.

INTERVENTION

Patients were randomly assigned to receive filgrastim (12 micrograms/kg of body weight per day) (n = 109) or placebo (n = 107) beginning within 12 hours of empiric therapy with tobramycin and piperacillin. Patients received treatment and remained in the study until the neutrophil count was greater than 0.5 x 10(9)/L and until 4 days without fever (temperature < 37.5 degrees C) had elapsed.

MEASUREMENTS

Days of neutropenia and fever and days in the study (hospitalization); time to resolution of fever and febrile neutropenia; and frequency of the use of alternative antibiotics.

RESULTS

Compared with placebo, filgrastim reduced the median number of days of neutropenia (3.0 compared with 4.0 days of a neutrophil count of < 0.5 x 10(9)/L; P = 0.005) and the time to resolution of febrile neutropenia (5.0 compared with 6.0 days; P = 0.01) but not days of fever (3.0 days for both groups). The frequency of the use of alternative antibiotics was similar in the two groups (46% compared with 41%; P = 0.48). The median number of days patients were hospitalized while on study was the same (8.0 days; P = 0.09); however, filgrastim decreased the risk for prolonged hospitalization (> 11 days, 4th quartile) by half (relative risk, 2.1 [95% CI, 1.1 to 4.1]; P = 0.02). In exploratory subset analyses, filgrastim appeared to provide the greatest benefit in patients with documented infection and in patients presenting with neutrophil counts of less than 0.1 x 10(9)/L.

CONCLUSIONS

Filgrastim treatment used with antibiotics at the onset of febrile neutropenia in patients with cancer who have received chemotherapy accelerated neutrophil recovery and shortened the duration of febrile neutropenia.

Prognostic value of immunophenotyping in acute myeloid leukemia. Australian Leukaemia Study Group

The diagnostic and prognostic value of immunophenotyping with 18 murine monoclonal antibodies (MoAbs) to a variety of leukocyte differentiation antigens was assessed in 168 adults aged 15 to 60 years with acute myeloid leukemia (AML). Patients were entered on the multicentre Australian Leukaemia Study Group M4 protocol, and were randomized to receive either standard or high-dose Ara-C together with daunorubicin and etoposide as induction chemotherapy, followed by standard consolidation and maintenance therapy. Diagnostic bone marrow aspirate (152 cases) or peripheral blood samples (16) were analyzed by indirect immunofluorescence and flow cytometry. MoAbs used were directed at myeloid (CD11b, CD13, CD14, CD15, CD33, CD41), lymphoid (CD2, CD3, CD7, CD9, CD10, CD19), or stem cell (HLA-DR, CD34, c-kit receptor) antigens, as well as the leukocyte integrins CD18 and CD49e, and the transferrin receptor CD71. Of the myeloid markers, CD13 and CD33 were the most useful diagnostically (71% and 79% of cases positive, respectively), with CD11b, CD14, and CD15 less commonly positive. A minority of cases expressed lymphoid antigens, either T cell (CD2 16%, CD3 7%, CD7 28%) or B cell (CD10 2%, CD19 7%). CD34 was detected on 42% and c-kit receptor on 48%. When patients were analyzed for response to treatment, CD2, CD9, and CD14 were significantly associated with complete remission rate: cases expressing these antigens had a poorer response than negative cases. In univariate analysis, CD11b+ cases had shorter periods of remission (relative risk of relapse, 2.33; P = .003) and shorter survival (relative death rate, 1.91; P = .006). In multivariate analysis, adjusting for other prognostic factors, CD9 and CD11b were significantly predictive of shorter survival. No other marker had a significant predictive effect. We conclude that myeloid MoAbs are useful in confirming the diagnosis of AML, but their prognostic value may be limited to CD11b. Lymphoid antigen expression is a consistent phenomenon in a minority of cases of AML, but appears to have little clinical significance.

Estradiol treatment increases viability of glioma and neuroblastoma cells in vitro

The present study provides evidence that 17-beta-estradiol (E2) exerts cytoprotective effects on both glial and neuronal cell lines. In C6 rat glioma cells, the addition of E2 to serum free media enhances live cell number by 40% at 24 h and 75% at 96 h when compared to serum free media conditions. E2 treatment of C6 cells in serum free medium did not increase thymidine uptake at any sampling time, indicating that the observed effect of E2 on C6 cell number was not due to a mitogenic effect of the steroid hormone. The addition of E2 to SK-N-SH cells in serum free media maintained both total and live cell number at a level comparable to the fetal bovine serum (FBS) treated cells at both 24 and 48 h. At 96 h after treatment with E2, total and live cell numbers were diminished relative to the 48-h sample and the 96-h FBS group, but were still more than twice the number observed in serum free media. Associated with the reduced effects of E2 at 96 h was an increase in the ratio of dead to total cells, although it remained about 50% less than the serum free group. Through 48 h, E2 exposure did not increase thymidine uptake in SK-N-SH cells, indicating that the effect of E2 on SK-N-SH cells was cytoprotective rather than mitogenic. Collectively, these data support a cytoprotective action of E2 on neuronal or glial cell types in vitro.

Measurement of functional severity of asthma in children

The usefulness of surveys for measuring the severity of asthma in school-age children depends on the availability of reliable and valid questionnaires. The aim of this study was to develop a measure of functional severity of asthma over the previous 12 mo, for use in population studies and in investigating treatment regimens. Of 10,198 children surveyed, 9,192 (90%) in school Years 2, 7, and 10 (mean ages 8, 13, and 16 yr) in Melbourne were screened for wheeze. The parents of the 1,267 children with wheeze were interviewed. Symptoms and restriction of activity due to asthma were analyzed using factor analysis and the partial credit version of the item response theory measurement model. The result was a continuous severity scale that was highly consistent with the data, and with goodness of fit statistics indicating the severity of 97% of children was well described by the scale. The scale correlated significantly with school absence due to wheeze (r = 0.35), functional impairment during the 2 wk before interview (Functional Status II-R [FSII-R], r = 0.30), visits to medical care for wheeze (r = 0.22), and amount of medication (r = 0.36). For descriptive purposes, a simple index with four bands of severity was developed from the continuous severity scale: low severity (47% of children with wheeze), moderate (30%), mild (18%), and high (5%). The scale and index facilitate standardized description of the impact of asthma on daily life on the basis of responses to six survey questions.

Ro 32-0432, a selective and orally active inhibitor of protein kinase C prevents T-cell activation

Several lines of circumstantial evidence support the assumption that protein kinase C (PKC) activation together with elevated levels of cytosolic Ca++ are necessary for T-cell activation and proliferation in response to a physiological stimulus, i.e., MHC class II restricted antigen presentation. By using a potent, cell-permeable and selective inhibitor of PKC, Ro 32-0432, we have tested this hypothesis. Ro 32-0432 inhibits interleukin-2 (IL-2) secretion, IL-2 receptor expression in, and proliferation of, peripheral human T-cells stimulated with phorbol ester together with phytohemagglutin or anti-CD3, but does not inhibit IL-2 induced proliferation in cells already stimulated to express IL-2 receptors. Proliferation of the influenza peptide antigen HA 307-319-specific human T-cell clone (HA27) after exposure to antigen-pulsed autologous presenting cells was also inhibited by Ro 32-0432. Oral administration of Ro 32-0432 inhibited subsequent phorbol ester-induced edema in rats demonstrating the systemic efficacy of the compound to inhibit PKC-driven responses. Induction of more physiologically T-cell driven responses such as host vs. graft responses and the secondary paw swelling in adjuvant-induced arthritis were also inhibited by Ro 32-0432. These data demonstrate the crucial role for PKC in T-cell activation and that selective p.o. bioavailable PKC inhibitors are efficacious in preventing T-cell driven chronic inflammatory responses in vivo. Inhibition of PKC represents an important mechanistic approach to prevent T-cell activation and compounds of this class may have important therapeutic applicability to chronic inflammatory and autoimmune diseases.

The assessment of different methods of data reduction for qualitative assays

An increasing number of biochemical tests for the detection of ailments such as hepatitis, AIDS, listeria poisoning etc are becoming qualitative in nature since the concern is over whether contamination is present or not rather than to what degree it is present. Many tests have an underlying quantitative scale that is dichotomised by the calculation of a detection limit, whereby a result is deemed negative, say, if its assay response is less than the detection limit and positive otherwise. A number of methods have been proposed for determining the detection limit and a few authors have tried to compare some of these methods. To date, as far as we are aware, these comparisons have been neither exhaustive nor conclusive. We propose a comparison criterion based on the false positive and false negative rates and use this criterion to assess five different methods via a simulation study. For the simulation model used, under the conditions imposed, we conclude that a detection limit based on control samples is probably the most efficient. Each method of calculating the detection limit has a coefficient associated with it for determining the exact position of the detection limit. The criteria, to date, for selecting the value of this coefficient seem arbitrary since whole numbers are often quoted, presumably reflecting convenience. Our simulation approach provides a possible method for determining the value of the coefficient which gives rise to a specified false positive or false negative rate.

Measurement of cremophor EL following taxol: plasma levels sufficient to reverse drug exclusion mediated by the multidrug-resistant phenotype

BACKGROUND

Paclitaxel (Taxol) is the first of a new class of cytotoxic agents with activity against tumors resistant to other drugs. For clinical use, paclitaxel is currently formulated in a vehicle of 50% ethanol and 50% polyethoxylated surfactant Cremophor EL (Cremophor). We have previously shown that Cremophor will block the P-glycoprotein drug efflux pump responsible for the multidrug-resistant phenotype. Overexpression of P-glycoprotein is one mechanism of in vitro resistance to a number of currently used cytotoxic agents including paclitaxel.

PURPOSE

Our aim was to develop a bioassay to measure plasma levels of Cremophor and to determine whether or not plasma levels of Cremophor achieved during paclitaxel therapy are sufficient to inhibit the activity of the P-glycoprotein.

METHODS

All patients studied had histologically proven, advanced ovarian carcinoma with measurable or evaluable disease and had received at least one prior platinum-containing regimen. The bioassay used flow cytometry to measure the increase in equilibrium intracellular daunorubicin levels in multidrug-resistant human T-cell leukemia cells (CEM/VLB100) in the presence of a series of concentrations of Cremophor. Levels of Cremophor were measured in plasma from 21 patients after a 3-hour infusion of 135 or 175 mg/m2 paclitaxel. Both dose levels were given following premedication with oral dexamethasone, intravenous promethazine hydrochloride, and intravenous cimetidine. The Cremophor bioassay involved incubation of CEM/VLB100 cells (5 x 10(5)) for 1 hour with 2 micrograms/mL daunorubicin in 0.5 mL HL-1 medium plus 0.5 mL plasma prior to flow cytometric analysis. Pretreatment plasma was used to derive a standard curve for the effect of Cremophor on equilibrium daunorubicin levels. All measurements were done in triplicate.

RESULTS

In vitro experiments indicated that, for maximal inhibition of P-glycoprotein activity, concentrations of Cremophor of 0.1% (vol/vol) were required. At the end of a 3-hour infusion of paclitaxel, plasma levels of Cremophor in 19 of 21 patients were 0.1% or higher and 0.09% in the remaining two. Concentrations of 5-20 microM paclitaxel dissolved in ethanol without Cremophor did not inhibit P-glycoprotein in this assay.

CONCLUSION

The concentrations of Cremophor measured in plasma drawn from patients after a 3-hour infusion of paclitaxel at 135 or 175 mg/m2 were found to be sufficient to inhibit P-glycoprotein activity in vitro.

IMPLICATIONS

The efficacy of paclitaxel against some tumors may be aided by its administration in a vehicle solution containing Cremophor in quantities that reach concentrations in the plasma sufficient to reverse multidrug resistance of neoplastic cells.

International comparison of asthma prevalence in children: Australia, Switzerland, Chile

The aim of the study was to determine if the prevalence of symptoms suggestive of asthma in school-age children was similar in three countries with differing language and culture. To answer this question, we used the same instrument, translated appropriately, for schoolchildren in Melbourne, Australia, St. Gallen, Switzerland, and La Serena, Chile. A three page respiratory symptoms questionnaire was issued to schools for distribution to children for completion by parents and return to the school. Three age groups were selected for study, based on the average age of the school grade. Grades were used with average ages of 7, 12, and 15 years, respectively. A total of 26,628 questionnaires were issued to parents (Australia, 10,981; Switzerland, 4,464; Chile, 11,183). The response rates for each country were 89% for Australia, 97.5% for Switzerland, and 71% for Chile. The prevalence of wheezing in the last 12 months for 7 year olds was 23.1% in Melbourne, 7.4% in St. Gallen, and 26.5% in La Serena; for 12 year olds it was 20.9% in Melbourne, 6.0% in St. Gallen, and 21.1% in La Serena; for 15 year olds it was 18.6% in Melbourne, 4.5% in St. Gallen, and 17.7% in La Serene. A history of wheezing was more common in boys than girls at age 7 in Melbourne and St. Gallen, but not La Serena. This difference was less at age 12 and was not seen at age 15. Among those who had reported wheezing in the last 12 months, bronchodilator use was reported by 83% (1,611/1,948) from Melbourne, 46% (118/259) from St. Gallen, and 47% (538/1,140) from La Serena.(ABSTRACT TRUNCATED AT 250 WORDS)

A novel in vivo model for the study of cartilage degradation

Methods of quantifying cartilage destruction are described using a sponge/cartilage implant model in the rat. A cylinder of bovine nasal cartilage was positioned in the center of a sponge which had been pretreated with an irritant. The sponge/cartilages were then implanted subcutaneously into the backs of rats for periods of up to 16 days. The implanted sponges were rapidly surrounded by granulation tissue, maximal on day 2, and infiltrated by inflammatory cells which reached peak levels on day 9. Analysis of the cartilage shows an initial increase in wet weight and rapid loss of glycosaminoglycans. These changes were later followed by loss of cartilage wet weight and significant loss of hydroxyproline content. In a separate study, the effects of Mycobacterium tuberculosis (Mtb), kaolin, and zymosan were compared (1 mg/sponge) and the results showed that only Mtb induced pronounced inflammation and degradation of cartilage. The cartilage degradation directly correlated with the granulation tissue weight, but not with cellular infiltration. We believe that this simple, reproducible in vivo model could be used to elucidate the mechanisms involved in the destructive process and evaluate the efficacy of inhibitors of cartilage degradation.

Comparison of quality-control rules used in clinical chemistry laboratories

Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et al. (Clin Chem 1977;23:1857-67) especially seems to have attracted the attention of users. Here we derive detailed results that enable the characteristics of the various Shewhart-type control schemes, including the multirule scheme (Clin Chem 1981;27:493-501), to be calculated and show that a fundamental formula proposed by Westgard et al. in the earlier paper is in error, although their derived results are not seriously wrong. We also show that, from a practical point of view, a suitably chosen Cusum scheme is near optimal for all the types and combinations of errors discussed, thereby removing the selection problem for the user.

Do diagnosis related groups separate the case-mix of a specialist children's hospital and a paediatric unit in a general hospital?

The ability of diagnosis related groups (DRG) and refinement diagnosis related groups (RDRG) to measure differences in case-mix was investigated using discharge data for patients < 18 years of age from three specialist children's hospitals and four district hospitals. While the three children's hospitals each had a greater percentage of RDRG for more complex patients, only one children's hospital had more complex patients based on DRG and RDRG cost weights and on the percentage of diagnoses per discharge. Cost weights based on USA practices may be inappropriate in Australia, and Australian weights will be necessary for firm conclusions. Refinement diagnosis related groups with appropriate cost weights may be acceptable measures of case-mix in specialist children's hospitals, but they have inherent limitations for paediatric patients in that many complex paediatric patients are ill very seriously with one disorder, whereas complex adult patients usually have secondary diagnoses and secondary procedures. Moreover, no DRG version developed in the US will be suitable for use in Australia unless it takes account of medical costs and transfer practice.

Comparison of quality-control rules used in clinical chemistry laboratories

Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et al. (Clin Chem 1977;23:1857-67) especially seems to have attracted the attention of users. Here we derive detailed results that enable the characteristics of the various Shewhart-type control schemes, including the multirule scheme (Clin Chem 1981;27:493-501), to be calculated and show that a fundamental formula proposed by Westgard et al. in the earlier paper is in error, although their derived results are not seriously wrong. We also show that, from a practical point of view, a suitably chosen Cusum scheme is near optimal for all the types and combinations of errors discussed, thereby removing the selection problem for the user.

Bias, prevalence and kappa

Since the introduction of Cohen's kappa as a chance-adjusted measure of agreement between two observers, several "paradoxes" in its interpretation have been pointed out. The difficulties occur because kappa not only measures agreement but is also affected in complex ways by the presence of bias between observers and by the distributions of data across the categories that are used ("prevalence"). In this paper, new indices that provide independent measures of bias and prevalence, as well as of observed agreement, are defined and a simple formula is derived that expresses kappa in terms of these three indices. When comparisons are made between agreement studies it can be misleading to report kappa values alone, and it is recommended that researchers also include quantitative indicators of bias and prevalence.

Relationship between myocardial collagen and echo amplitude in non-fibrotic hearts

The aim of the study was to investigate the relationship between myocardial collagen and regional echo amplitude in humans with non-fibrotic myocardium. The ratio of myocardial collagen to total myocardial protein was determined as the hydroxyproline/leucine ratio in endomyocardial biopsies obtained from the right ventricular side of the interventricular septum in orthotopically transplanted hearts. Regional echo amplitude was measured in the interventricular septum. Patients were studied prospectively. Twenty-five patients (five female, 20 male) who had undergone orthotopic cardiac transplantation were studied 355 to 2939 days (1009 +/- 718, mean +/- SD) post-transplantation at the time of annual cardiac catheterization and endomyocardial biopsy. Patient ages varied from 22 to 62 years (46 +/- 11). Donor ages were 14 to 47 years (25 +/- 8) and the ischaemic time, 90 to 245 min (151 +/- 42). Cardiac transplantation was performed for end-stage cardiac failure in all patients. The aetiology of cardiac failure was valvular heart disease in three, dilated cardiomyopathy in eight and ischaemic heart disease in the remainder. Echo amplitude studies were performed within 24 h of endomyocardial biopsy. All but one patient were on an immunosuppressive regime consisting of cyclosporine A and azathioprine with additional steroids in three. The remaining patient, who was the longest surviving patient in the study group, had never been treated with cyclosporine. This patient was maintained on steroids and azathioprine alone. No patient had clinical or histological evidence for acute cardiac rejection and all were clinically well. Five patients had angiographic evidence of coronary artery disease. All subject studies were performed at Harefield Hospital.(ABSTRACT TRUNCATED AT 250 WORDS)

Type III collagen content in the skin of postmenopausal women receiving oestradiol and testosterone implants

OBJECTIVE

To investigate the effect of subcutaneous oestradiol and testosterone on the proportion of type III collagen in the skin of postmenopausal women.

DESIGN

A cross sectional comparison.

SETTING

Dulwich Hospital menopause clinic.

SUBJECTS

Fourteen untreated women and 11 women who had received subcutaneous oestradiol and testosterone for a median 8.0 years (range 3-14). Ten of the untreated women received subcutaneous hormone implants and the effect on skin collagen was studied prospectively.

MEASUREMENTS

The proportion of type III collagen in skin biopsies taken from the lateral aspect of the thigh.

RESULTS

The median type III collagen content in the skin of the women who had received hormone replacement therapy (25.4%, range 21.4-30.2) was significantly higher (P < 0.01) than in the untreated women (19.6%, range 18.2-28.8). The proportion of type III collagen in the skin of 10 untreated women increased significantly (P < 0.01) from a median of 19.9% (range 18.2-23.9) to 22.4% (range 20.5-31.5) following 6 months of treatment with hormone implants.

CONCLUSION

This study indicates an increase in the proportion of type III collagen in women receiving hormone replacement therapy.

Hospitalisation of children under 15 years in Victoria

OBJECTIVE

To determine whether the separation rate from the hospital for children aged 0-15 years in Victoria was higher for those resident in the country area of the State in comparison with the metropolitan area and, if it was, to investigate possible explanations.

DESIGN

Discharge data from all public hospitals in Victoria for children aged 0-15 years for the financial years 1988-89, 1989-90 and 1990-91 were analysed with detailed analysis being done on the 1990-91 data set. Discharge rates were determined according to the local authority area of residence. Patients were grouped according to Diagnosis Related Groups (DRGs) version 5.

RESULTS

Children living in the country area showed a separation rate of 50 per cent greater than that for the metropolitan area. Separation rates for local authority areas were remarkably constant over the three years. Country local authority areas with the highest separation rates had separation rates for asthma and bronchitis (DRG 98), almost four times that of metropolitan residents, and for otitis media and upper respiratory infection (URI), a rate almost ten times that of metropolitan residents.

CONCLUSION

It is suggested that variation in medical practice was the most likely explanation for the observed differences.

Guidelines for the evaluation and management of family violence

The following guidelines were approved by the Board of Directors of the Canadian Psychiatric Association on April 12, 1992.

Prevalence of asthma in regional Victorian schoolchildren

OBJECTIVE

To determine whether the high prevalence of reported asthma in Melbourne schoolchildren is seen in rural Victoria.

DESIGN

A questionnaire on respiratory symptoms was distributed to children to be completed by parents and returned to the school. Results were compared with a previous Melbourne study.

SETTING

Two hundred and twenty-seven government and non-government primary schools in five rural regions of Victoria: coast, wheatbelt, riverland, highland and Latrobe valley.

SUBJECTS

All children enrolled in grade 2 were invited to join the study. Parents completed questionnaires for 4661 children after 4886 questionnaires were distributed (response rate, 95%).

MAIN OUTCOME MEASURE

History of wheeze in the past 12 months.

RESULTS

The overall prevalence of wheeze in the last 12 months was 23.6%. There was a significant difference overall in this rate across the five rural areas and Melbourne, with the Latrobe Valley (26.2%) and highland areas (25.0%) having the highest rate, and the wheatbelt the lowest (19.6%). The spectrum of severity of asthma was similarly distributed across rural regions, although severe episodes were significantly more frequently reported by parents from rural areas than by parents in Melbourne. The reported use of bronchodilators and diagnosis of asthma showed a similar pattern of variation to that of the 12-month prevalence of wheeze.

CONCLUSION

The prevalence of asthma in 7-year-old children is similar for rural Victoria as a whole compared with Melbourne, but there is variability in asthma prevalence in individual rural areas which is difficult to account for in terms of known environmental precipitants.

The severe combined immunodeficient (SCID) mouse as a model for human myeloid leukemias

Recent work has demonstrated the ability of lymphoblastic leukemias of pre-B- and T-cell origin to grow in severe combined immunodeficient (SCID) mice with a pattern reminiscent of the human clinical disease. Here, we investigated the possibility of engrafting human myeloid leukemias using both established cell lines and primary patient material. Whereas the two growth factor-independent cell lines K562 and U937 grew aggressively and induced leukemia in these animals, three other myeloid cell lines which require interleukin 3 or granulocyte-macrophage colony-stimulating factor for continuous growth in vitro failed to induce disease. Primary bone marrow and peripheral blood cells from five out of seven patients with different types of myeloid leukemias (undifferentiated, megakaryoblastic, monoblastic and chronic myelogenous leukemia in blast crisis) induced patterns of leukemic infiltration that were distinct for each leukemia subtype. The diagnosis of leukemia in SCID mice was established by microscopic detection of myeloblasts in the bone marrow, peripheral blood and, in some instances, in extramedullary sites, including the central nervous system and gonads. The karyotype and phenotype of the blasts recovered from mouse tissues were identical to those of the original patient cells. Moreover, human specific ALU sequences were amplified from the bone marrow DNA by polymerase chain reaction. Despite their ability to grow in vivo by serial transfers in SCID mice, the leukemic cells recovered from mouse tissues could not be maintained in vitro, even in the presence of recombinant cytokines. Overall, these data indicate that the SCID mouse may represent a useful animal model for human myeloid leukemias and for the development of new pharmacological and molecular approaches to therapy.

Guidelines for a non sexist (gender-sensitive) doctor-patient relationship

The following guidelines have been adapted from the Canadian Psychological Association's Guidelines on Therapy and Counselling with Women (1) and have undergone revisions and additions to make them suitable for both male and female patients and useful for physicians. The guidelines were approved by the Board of Directors of the Canadian Psychiatric Association October 4, 1991.

Evaluation of the properties and reliability of a clinical severity scale for acute asthma in children

The inter-observer agreement (reliability) and validity of a clinical asthma severity scale (ASS) derived from separate scores of wheeze, heart rate and accessory muscle use (each on a 4-point scale) were studied in 60 children aged between 6 months and 17 years (mean 5.4 years). Independent assessments of these clinical parameters were made by two paediatricians, and they also rated patients as having a mild, moderate, severe or very severe acute episode (clinical judgement rating, CJR). Oxygen saturation (SaO2) was measured concurrently by a Biox 3700 pulse oximeter and readings were categorized as mild (SaO2 greater than or equal to 94%), moderate (91-93%) and severe (less than 91%). Agreement between clinicians was assessed by the weighted kappa statistic (kappa W). Agreement for the ASS score compared to the severity grade obtained from SaO2 was slight (kappa W = 0.34) and compared to CJR the kappa W was 0.55. An ASS score of moderate or worse (greater than 3) had sensitivity of 97% and specificity of 50% for prediction of admission. The maximum frequency and duration of nebulizer therapy following admission were significantly greater for severe patients than for moderate patients. Length of hospital stay did not reflect the ASS score in the emergency department but total duration of functional disability increased with ASS score. The substitution of an adjusted heart rate score for the raw heart rate score used in ASS detracted from scale performance. The ASS is an imprecise but reasonable quantitative measure of the severity of an acute episode of asthma.(ABSTRACT TRUNCATED AT 250 WORDS)

Phase I clinical and pharmacokinetics study of high-dose toremifene in postmenopausal patients with advanced breast cancer

Toremifene is an antiestrogen that binds strongly to estrogen receptors (ER). A total of 19 previously treated postmenopausal women with metastatic breast cancer whose performance status was good and whose ER status was positive or unknown were studied to determine the maximum tolerated dose of toremifene. Cohorts of patients received 200, 300, or 400 mg/m2 p.o. daily until relapse or unacceptable toxicity had occurred. Nausea, vomiting, and dizziness were dose-related. Three of five patients receiving 400 mg/m2 experienced moderate or severe vomiting and another developed reversible disorientation and hallucinations. Mild sweating, peripheral edema, vaginal discharge, and hot flushes were encountered at all doses. Reversible corneal pigmentation was identified in seven cases but was not of clinical importance. The pharmacokinetics of toremifene was studied weekly and in detail on day 42 using a high-performance liquid chromatographic (HPLC) assay that identified the parent compound and three active metabolites, N-desmethyltoremifene, (deaminohydroxy)toremifene, and didemethyltoremifene. Steady state was achieved at 1-3 weeks. The toremifene area under the curve and the maximal concentration were dose-dependent at high doses. The recommended phase II dose is 300 mg/m2 p.o. daily.

Limited small cell lung cancer: the effect of radiotherapy on local control following response to chemotherapy

The survival and rate of chest infield relapse was examined in 48 patients with limited disease small cell lung cancer (LSCLC) who had achieved complete (CR) or partial response (PR) following three courses of chemotherapy. During 1985-1986 chemotherapy consisted of carboplatin and etoposide and during 1986-1987, of etoposide, carboplatin, cyclophosphamide, and vincristine (ECCO). After three courses of chemotherapy, chest irradiation (50 Gy in 25 fractions over 5 weeks) was given to encompass the original tumor volume. Complete responders were also given prophylactic cranial irradiation, 30 Gy in 10 fractions over 2 weeks. Overall median survival of all patients receiving chest irradiation was 17 months from commencement of radiotherapy. The infield relapse-free survival at 24 months was 49% (95% confidence interval: 32-66%). Patients who had only achieved a PR at the time of irradiation were more likely to relapse in the chest than complete responders (p = 0.09). We conclude that local relapse remains a major cause of failure in patients with LSCLC in spite of sequential high dose radiotherapy given to patients who have responded to chemotherapy.

Pulse oximetry in acute asthma

The predictive value of pulse oximetry was evaluated in 100 patients who attended the emergency department with acute asthma. Oximetry after treatment with a cut off point of less than 91% had a sensitivity of 42% and specificity of 78% for unfavourable outcome, and oximetry before treatment had a sensitivity of 36% and a specificity of 57%. Despite its low sensitivity, oximetry after treatment does seem to have a role in minimising diagnostic errors in the emergency department, but only when used in conjunction with clinical assessment.

Prevalence of asthma in Melbourne schoolchildren: changes over 26 years

OBJECTIVES

To determine the prevalence of asthma in the past 12 months in Melbourne schoolchildren aged 7, 12, and 15 years and to compare the prevalence of a history of asthma with that of 26 years ago.

DESIGN

A questionnaire on respiratory symptoms was distributed to children for completion by parents and return to the school. Subjects were selected by a stratified cluster design.

SETTING

Government and non-government schools in the greater Melbourne area, Australia.

SUBJECTS

10,981 children. Parents completed questionnaires for 3324 children aged 7, 2899 aged 12, and 2968 aged 15. The overall response rate was 90%.

MAIN OUTCOME MEASURES

History of wheeze or asthma in the past 12 months and in lifetime.

RESULTS

The prevalences of wheeze in the past 12 months were 23.1%, 21.7%, and 18.6% for 7, 12, and 15 year olds respectively. A history of wheeze was more common in boys than in girls at age 7 (443/1711 v 324/1614) and 12 (418/1767 v 322/1718) but not at age 15. Overall, 78% (1548) of those reporting wheeze also reported a history of asthma and 83% (1611) had used a bronchodilator. The prevalence of a history of asthma among 7 year olds was 46% compared with 19.1% in the 1964 survey, an increase of 141%.

CONCLUSIONS

The current prevalence of asthma in Melbourne schoolchildren is high and has risen substantially over the past 26 years.

Concurrent radiotherapy and carboplatin in non small-cell lung cancer: a pilot study using conventional and accelerated fractionation

Thirteen patients with unresectable non small cell lung cancer were treated with radical radiotherapy and carboplatin administered concurrently. The first 6 patients were treated to a total dose of 60 Gy in 30 fractions in 6 weeks, with carboplatin 70 mg/m2/day on days 1 to 5 during weeks 1 and 5 of radiotherapy. The remaining 7 patients were given 60 Gy in 30 fractions in 3 weeks, treating twice a day (accelerated fractionation). Carboplatin was given as above but only during week 1 of radiotherapy. Twelve patients completed radiotherapy without interruption but 2 patients developed WHO grade 3 neutropenia. Major toxicity was oesophagitis, one patient requiring nasogastric feeding. Average duration of dysphagia (any grade) in the accelerated fractionation group was 21 weeks. Four patients achieved good partial responses even though initial tumour volume was large. We conclude that this treatment is associated with increased but acceptable early mucosal toxicity.

The problem of neonatal diagnosis related groups

There is, as yet, no satisfactory set of Diagnosis Related Groups to measure the casemix and consumption of hospital resources in the care of newborn infants. To obtain further information, infants less than 28 days when admitted to the Royal Children's Hospital and Royal Women's Hospital, Melbourne were analysed. Both Refined Diagnosis Related Groups and Pediatric Modified Diagnosis Groups were used. Neonatal groups of the Pediatric Modified system included all infants aged less than 28 days on admission, whereas Refined Diagnosis Related Groups includes only those newborn infants who have diagnoses specific to the newborn period. Refined Diagnosis Related Groups and their higher order contained 1,237 discharges. Standard deviation and coefficient of variation and length of stay in these RDRG were high. However, if the patients in these RDRGs were further grouped according to PMDRGs, there appeared to be more homogeneous missing. The R2 values were four times higher. It is recommended that a satisfactory form of neonatal DRGs is to regroup patients in neonatal RDRGs through a PMDRG grouper.

Autopsies in an area health service: a quality assurance review

The Hunter Area Health Service Quality Liaison Group reviewed autopsy practice in the Hunter Area, focussing upon clinical and resource utilisation effectiveness. Findings are discussed. Conclusions support views expressed in recent literature on the subject. The conclusion is reached that despite increase in consumption of limited resources, autopsies remain an integral component of quality care and should increase in number. Some recommendations are proffered to maximise utility and cost effectiveness in the future.

The polymerase chain reaction in the diagnosis of vertically transmitted HIV infection

The presence of HIV-1 DNA sequences in DNA from peripheral blood mononuclear cells (PBMCs) was investigated in a two-stage polymerase chain reaction ('double' PCR) using four sets of nested primers. The PBMCs tested were obtained from 46 children born to HIV-seropositive mothers, seven 'control' children born to HIV-seronegative mothers and seropositive fathers, and 45 healthy adult blood donors who were HIV seronegative. Nine of the children had symptomatic HIV infection and other laboratory features characteristic of HIV infection: all nine were PCR-positive with each set of primers in each of their 22 blood samples tested. The remaining 44 children had no clinical or laboratory evidence of HIV infection, and each of their 50 samples was PCR-negative with each set of primers, as were all blood donor samples. PCR-positive samples were tested in more detail using two of the sets of primers, which spanned hypervariable regions in the env gene. Polyacrylamide gel electrophoresis of DNA amplified from these regions yielded patterns of amplified DNA length variation which were characteristic for each child, and which changed little with time (in serial samples obtained over periods of 3-7 months). This excluded contamination as a cause of PCR positivity. This is the first report of the use of a double PCR for the diagnosis of HIV infection. The results demonstrate the specificity of this PCR method in diagnosis, with failure to reveal in this cohort any cases of vertically transmitted HIV-1 infection in addition to those already confirmed by conventional laboratory techniques.

Phase II trial of carboplatin in the management of malignant mesothelioma

Thirty-one patients with advanced malignant mesothelioma, previously untreated or having received only one prior cytotoxic regimen, were treated in a prospective, single-arm phase II trial with carboplatin (NSC 241240) at a dose of 150 mg/m2 per day intravenously (IV) for 3 days (450 mg/m2/course). One complete remission and four partial remissions were achieved, yielding an overall objective response rate of 16% (95% confidence interval [CI], 5.4% to 34%). The median duration of remission was 8 months (range, 5 to 17). Nonhematological toxicity was mild (only 12% with World Health Organization [WHO] grade 3 vomiting); 16% suffered WHO grade 3 to 4 hematological toxicity, but there were no life-threatening episodes and no treatment-related deaths. Carboplatin has modest activity against malignant mesothelioma and, because of its low toxicity, has a role in the management of this disease.

Diagnosis related groups, refined diagnosis related groups and pediatric modified diagnosis related groups in specialist children's hospitals

The value of Diagnosis Related Groups, Refinement Diagnosis Related Groups and Pediatric Modified Diagnosis Related Groups in measuring the output of specialist children's hospitals was evaluated by the examination of discharge data for 1987-88 from three major Australian children's hospitals and four district hospitals. The study included all patients aged 0-18 years but excluded those with specific neonatal diagnoses. Findings indicated that Refinement Diagnosis Related Groups seem to give a better measure of the output of specialist children's hospitals than Version 5 Diagnosis Related Groups in that they explained a higher proportion of variation of length of stay. Pediatric Modified Diagnosis Related Groups developed in the United States of America for specialist children's hospitals overall did not seem to have major advantages over Refinement Diagnosis Related Groups but there were some specific Pediatric Groups that appeared beneficial. Further modification of the Refinement Diagnosis Related Groups could allow these advantages to be incorporated. Overall it seems preferable for there to be a similar system measuring output of both children's hospitals and general hospitals and this could be achieved by some minor changes to the Refinement Diagnosis Related Groups.

Dose intensity and outcome with combination chemotherapy for germ cell carcinoma. Australasian Germ Cell Trial Group

Two hundred and fifty-three patients with advanced stage germ cell carcinoma received induction chemotherapy with vinblastine, bleomycin and cisplatin, sometimes with subsequent surgical resection of residual masses. Overall, 191 patients (76%) achieved complete remission or no evidence of disease after surgery (CR + NED). With 64 months median follow-up only 24 patients have relapsed (13%) and 68% of all patients treated are long-term survivors and 84% of patients entering CR + NED are alive. Toxicity with this chemotherapy was considerable, including seven deaths from leukopenia and septicaemia and eight deaths from bleomycin lung toxicity. Dose reductions or omissions of the drug from the treatment programme was necessary with cisplatin in 8% of patients, with vinblastine in 37% and with bleomycin in 35% of patients. Analysis of these alterations in dose intensity for each drug revealed that initial treatment response and subsequent survival were not compromised by reductions in intended doses of drug administered for either vinblastine or bleomycin. Too few patients had dose reductions of cisplatin for meaningful analysis. This apparent lack of major dose-response effect for either vinblastine or bleomycin in the present treatment programme for germ cell carcinoma has prompted the initiation of a randomized study to determine whether deletion of bleomycin from treatment for patients with good prognostic pretreatment characteristics improves the therapeutic index of this very successful therapy.