'Front and back' flaps for multiple dorsal and palmar digital skin loss

We describe a technique modification of the 'many tailed' flaps for multiple digital defects in adjacent digits described in 1980. This is a versatile technique for providing cover to multiple palmar and dorsal defects of the digits, avoiding the need to syndactylize digits, and when it is not desirable or adequate to perform multiple local flaps to cover the losses. The technical modifications are use of donor closure to adjust the position of the flaps in opposition, sequential donor closure to accurately place subsequent flaps, and raising flaps from less to more lax donor skin to avoid drift of donor site position.

Phase II study of vinflunine in patients with metastatic renal cell carcinoma

PURPOSE

An open-label, multicentre, non-comparative phase II trial to determine the response rate of intravenous vinflunine as first line chemotherapy in patients with metastatic renal cell carcinoma (RCC).

PATIENTS AND METHODS

Patients with metastatic RCC were treated with vinflunine 350 mg/m2 (n = 11) or 320 mg/m2 (n = 22) administered intravenously every 21 days.

RESULTS

Out of 33 patients included in this study, one partial response was observed in the group treated at 350 mg/m2 and none in the group receiving 320 mg/m2 resulting in a response rate in this population of 9.1% (95% CI: 0.2-41.3). Median progression free survival was 5.6 months (95% CI: 2.8-14.4) for patients treated at 350 mg/m2, and 3.3 months (95% CI: 1.6-6.4) for those treated at 320 mg/m2.The median survival time was 10.4 months (95% CI: 6.8-12.4) for the whole study population. The principal toxicities were grade 3/4 neutropaenia -90.9% at 350 mg/m2 and 68.1% at 320 mg/m2, febrile neutropaenia was recorded in 3 patients (27.3%) at 350 mg/m2 and in 5 patients (22.7%) at 320 mg/m2. One episode of thromboembolic event was reported in 1 patient at each dose level.

CONCLUSION

Vinflunine given intravenously once every 3 weeks has not shown any clinically relevant activity in the management of patients with metastatic renal cell carcinoma; tolerance of the treatment was better at a dose of 320 mg/m2 than at 350 mg/m2.

Leprosy in Britain: 50 years experience in Liverpool

BACKGROUND

Leprosy is a chronic infection that presents with varying dermal and neurological symptoms, and which can lead to extensive disability and morbidity, often with accompanying social stigma.

AIM

To review the patients presenting to the Liverpool School of Tropical Medicine (LSTM) between 1946 and 2003, looking specifically at country of birth and of infection, details of clinical presentation, diagnosis, management and reactions.

DESIGN

Retrospective record review.

METHODS

We retrieved all available clinical records for patients seen between 1946 and 2003 (n = 50), consisting of letters, hospital and LSTM casenotes, and some radiographs and photographs. Any history of tuberculosis or diabetes was recorded.

RESULTS

Most patients (64%) were born in the Indian subcontinent, and most were thought to have contracted the disease there (62%). Features at presentation included anaesthetic skin lesions in 19 (36%), hypopigmentation in 15 (30%), and peripheral nerve enlargement in 25 (50%). Diagnoses were made by a combination of clinical data and biopsy (60%), and slit skin smears were positive for acid-fast bacilli in 61% of multibacillary patients. Initial presentation was with a leprosy reaction in five cases (10%), and reactions were documented in 42% of all patients. Treatments were varied, progressing from traditional Eastern medicine to the WHO-approved multidrug therapy in use today, with prophylaxis for children and close contacts.

DISCUSSION

Leprosy remains an important diagnosis to consider in patients with a history of work or travel in the tropics, and is a diagnosis with far-reaching medical, social and emotional consequences.

Chronic Strongyloides stercoralis infection in former British Far East prisoners of war

BACKGROUND

Chronic infections with the nematode worm Strongyloides stercoralis can occur in former WWII Far East prisoners of war (FEPOWs). The condition may be asymptomatic, but frequently causes a characteristic urticarial 'larva currens' rash. Under conditions of immunosuppression (particularly systemic corticosteroid treatment) potentially fatal dissemination of larvae ('hyperinfection') may occur.

AIM

To review our total experience of strongyloidiasis in former FEPOWs, and investigate its prevalence, characteristics and risk factors.

DESIGN

Retrospective case series.

METHODS

We reviewed 2072 records of all FEPOWs seen at the Liverpool School of Tropical Medicine, 1968-2002. Cases with strongyloidiasis were compared with non-infected controls.

RESULTS

There were 248 (12%) with strongyloidiasis. Diagnostic features included larva currens rash (70%), eosinophilia (66%), positive faecal culture (30%), positive faecal microscopy (26%), and positive serology (64%). Mean (+/-SD) age of cases was 65 +/- 7 years, and as expected, their blood eosinophil counts were significantly higher than controls (775 vs. 238 x 10(6)/l, p < 0.001). Captivity on the Thai-Burma Railway (vs. elsewhere) was significantly associated with strongyloidiasis (78% cases vs. 40% controls, OR 4.19, CI 2.70-6.81, p < 0.001). In terms of prevalence, strongyloidiasis occurred in 166/1032 men imprisoned on the Burma Railway (16.1%). Malaria (88% vs. 69%, p < 0.001) and tropical ulcer (53% vs. 42%, p < 0.02) were more common amongst cases than controls, probably because these diseases were very common on the Burma Railway.

DISCUSSION

S. stercoralis infection is common amongst ex-FEPOWs, particularly those from the Thai-Burma Railway project. It is usually characterized by a 'larva currens' rash and marked eosinophilia. The condition is eminently treatable, and continued diagnostic surveillance is needed, if cases of potentially fatal hyperinfection are to be avoided.

Potential role for peroxisome proliferator activated receptor (PPAR) in preventing colon cancer

BACKGROUND

Peroxisome proliferator activated receptors (PPARs) are nuclear hormone receptors involved in genetic control of many cellular processes. PPAR and PPAR have been implicated in colonic malignancy. Here we provide three lines of evidence suggesting an inhibitory role for PPAR in colorectal cancer development.

METHODS

Levels of PPAR mRNA and protein in human colorectal cancers were compared with matched non-malignant mucosa using RNAse protection and western blotting. APC(Min)/+ mice were randomised to receive the PPAR activator methylclofenapate 25 mg/kg or vehicle for up to 16 weeks, and small and large intestinal polyps were quantified by image analysis. The effect of methylclofenapate on serum stimulated mitogenesis (thymidine incorporation), linear cell growth, and annexin V and propidium iodide staining were assessed in human colonic epithelial cells.

RESULTS

PPAR (mRNA and protein) expression levels were significantly depressed in colorectal cancer compared with matched non-malignant tissue. Methylclofenapate reduced polyp area in the small intestine from 18.7 mm(2) (median (interquartile range 11.1, 26.8)) to 9.90 (4.88, 13.21) mm(2) (p=0.003) and in the colon from 9.15 (6.31, 10.5) mm(2) to 3.71 (2.71, 5.99) mm(2) (p=0.009). Methylclofenapate significantly reduced thymidine incorporation and linear cell growth with no effect on annexin V or propidium iodide staining.

CONCLUSIONS

PPAR may inhibit colorectal tumour progression, possibly via inhibition of proliferation, and may be an important therapeutic target.

Phase II study of thalidomide in the treatment of recurrent glioblastoma multiforme

Treatment options and prognosis remains poor for patients with recurrent glioblastoma multiforme. These tumors are highly vascularised and over express angiogenic factors such as vascular endothelial growth factor and may potentially be responsive to antiangiogenic therapies. We present the results of a phase II trial of Thalidomide, an antiangiogenic agent, in the treatment of recurrent glioblastoma multiforme. Patients were treated with 100 mg/day of Thalidomide, increased at weekly intervals by 100 mg to a maximum tolerated dose of 500 mg/d. Forty-two patients were enrolled, with 38 patients being assessable for response and 39 for toxicity. Two patients (5%) achieved a partial response and 16 (42%) had stable disease. The median survival was 31 weeks and the 1-year survival was 35%. Patients who had a partial response or stable disease had either a stabilisation or improvement in quality of life scores or performance status. Overall Thalidomide was well tolerated with no grade 4 toxicities and no treatment related deaths. The median maximum tolerated dose was 300 mg/day. The most common toxicity was fatigue to which patients developed tachyphylaxis. There was no correlation demonstrated with plasma vascular endothelial growth factor levels and response or survival. Thalidomide is a well-tolerated drug that may have some activity in the treatment of recurrent glioblastoma. Optimum dosing with antiangiogenic agents is currently under investigation. Chronic low dose therapy may be required to see conventional responses or improvements in time to progression. The dose required to achieve optimal biological impact may be better defined once we have established reliable surrogate endpoints.

Binding of aryl hydrocarbon receptor (AhR) to AhR-interacting protein. The role of hsp90

The aryl hydrocarbon receptor (AhR) has been shown to interact with an immunophilin-like molecule known as AhR-interacting protein (AIP) and to enhance AhR function. We show here that AIP associates with AhR homologues from mouse and fish, which can bind ligands such as dioxin, but nonligand binding homologues from Caenorhabditis elegans or Drosophila do not bind to AIP. However, a minimal ligand-binding domain of the AhR is incapable of binding AIP. The binding of AIP to AhR in reticulocyte lysate shows several of the characteristics of an hsp90-dependent process, including sensitivity to geldanamycin and temperature and a requirement for ATP or nonhydrolyzable analogues. Purified AIP binds to the C terminus of hsp90, and mutation of a conserved basic residue in the tetratricopeptide repeats of AIP (K266A, analogous to K97A in protein phosphatase 5) abolishes binding to hsp90. Mutation of K266A in AIP reduces binding to AhR by 75-80%; the geldanamycin sensitivity of this complex shows that AhR stabilizes the AIP-hsp90-AhR complex. The alpha-helical C terminus of AIP, which is outside the tetratricopeptide repeat domain, is absolutely required for binding to AhR as shown by deletions of the C-terminal 5 amino acids or alanine-scanning mutagenesis, but it is not required for binding of AIP to hsp90. The data support a model where 1) AIP binds to both hsp90 and AhR; 2) hsp90 is required for AhR-AIP binding; and 3) the binding of AhR to AIP stabilizes the AIP-hsp90-AhR complex.

CYP2E1 and CYP4A as microsomal catalysts of lipid peroxides in murine nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) and alcoholic liver disease have similar pathological features. Because CYP2E1 plays a key role in alcoholic liver disease with its ability to stimulate lipid peroxidation, we tested the proposal that CYP2E1 could also be a factor in the development of NASH. In a dietary model - mice fed a methionine- and choline-deficient (MCD) diet - liver injury was associated with both induction of CYP2E1 and a 100-fold increase in hepatic content of lipid peroxides. Microsomal NADPH-dependent lipid oxidases contributed to the formation of these lipid peroxides, and in vitro inhibition studies demonstrated that CYP2E1 was the major catalyst. To further define the role of CYP2E1 as an initiator of oxidative stress in NASH, Cyp2e1(-/-)mice were administered the MCD diet. CYP2E1 deficiency neither prevented the development of NASH nor abrogated the increased microsomal NADPH-dependent lipid peroxidation, indicating the operation of a non-CYP2E1 peroxidase pathway. In Cyp2e1(-/-) mice with NASH (but not in wild-type mice), CYP4A10 and CYP4A14 were upregulated. Furthermore, hepatic microsomal lipid peroxidation was substantially inhibited by anti-mouse CYP4A10 antibody in vitro. These results show that experimental NASH is strongly associated with hepatic microsomal lipid peroxidation. CYP2E1, the main enzyme associated with that process in wild-type mice, is not unique among P450 proteins in catalyzing peroxidation of endogenous lipids. We have now identified CYP4A enzymes as alternative initiators of oxidative stress in the liver.

Species differences in peroxisome proliferation; mechanisms and relevance

Peroxisome proliferators are a class of structurally diverse chemicals, which induce liver carcinogenesis in rodents through interaction and activation of the Peroxisome Proliferator-Activated Receptor alpha (PPARalpha). PPARalpha agonists elicit a powerful pleiotropic response, which include hypolipidaemia. We have examined the response of species that are classically unresponsive to peroxisome proliferators. Whereas hamster responds to PPARalpha agonists by hepatomegaly and induction of marker genes, the guinea pig does not undergo hepatomegaly or induction of marker genes, such as CYP4A13. Both the hamster and the guinea pig have PPARalpha, and the guinea pig receptor has been characterised to be fully functional, as demonstrated in reporter gene expression assays. However, the guinea pig PPARalpha is expressed at low levels in liver, and the currently favoured hypothesis to explain species differences in hepatic peroxisome proliferation invokes the low level of PPARalpha as the principal determinant of species responsiveness. However, the demonstration that guinea pigs and humans undergo hypolipidaemia induced by PPARalpha-agonists calls into question the mode of action of PPARalpha agonists in "non-responsive" species.

Effects of group CBT on the survival time of patients with metastatic breast cancer

We have recently reported the psychological outcome of a group Cognitive Behaviour Therapy (CBT) intervention with patients who had metastatic breast cancer. The data of 92 patients who were retained at the first follow-up assessment revealed short-term improvements on measures of mood and self-esteem amongst therapy participants. These changes were not sustained at the 3- and 6-month follow-up assessments. This report describes a survival analysis of 121 patients who entered the study, at 5 years after its commencement. The analysis, based on the Cox Proportional Hazards Regression model, revealed no survival advantage associated with the intervention. Only medical prognostic factors such as Eastern Cooperative Oncology Group (ECOG) performance status, visceral metastases and chemotherapy treatment significantly predicted patients' survival time. The findings of this study are compared with those of two earlier studies which also examined the survival effects of a group psychological intervention with metastatic breast cancer patients.

A group cognitive behaviour therapy programme with metastatic breast cancer patients

One-hundred and twenty-four patients with metastatic breast cancer were randomised to either a group Cognitive Behaviour Therapy (CBT) intervention, or to a no-therapy control group condition. Both groups received standard oncological care; however, therapy recipients also attended eight weekly sessions of group CBT, followed by a family night, and three further monthly sessions. Patients completed the 'Profile of Mood States' (POMS) and the Coopersmith Self-esteem Inventory (CSI) before and after therapy, and at 3 and 6 month follow-up periods. Outcome data in the period following therapy showed reduced depression and total mood disturbance, as well as improved self-esteem amongst therapy participants, relative to a no-therapy control group. These improvements were no longer evident at the 3 or 6 month follow-up assessments. We also report on the difficulties associated with conducting a group intervention with this patient cohort.

Epoetin alpha prevents anaemia and reduces transfusion requirements in patients undergoing primarily platinum-based chemotherapy for small cell lung cancer

Anaemia commonly occurs in cancer patients receiving chemotherapy, often necessitating blood transfusion. This multicentre study was designed to evaluate the efficacy and safety of epoetin alpha in preventing the decline in haemoglobin (Hb) level, and to determine whether the transfusion requirement could be reduced, in patients receiving 4-6 cycles of primarily platinum-based combination cyclic chemotherapy for small cell lung cancer (SCLC). A total of 130 non-anaemic SCLC patients were randomized to receive no additional treatment (n = 44), epoetin alpha 150 IU kg(-1) subcutaneously (s.c.) three times a week (n = 42) or 300 IU kg(-1) s.c. three times a week (n = 44). Reductions in epoetin alpha dosage were made during the study if Hb level increased to >15 g dl(-1). The mean weekly dosage was 335 and 612 IU kg(-1), respectively, in the two active treatment groups. Significantly fewer (P < 0.05) epoetin alpha-treated patients experienced anaemia (Hb < 10 g dl(-1)) during the course of chemotherapy (300 IU kg(-1), 39%; 150 IU kg(-1), 48%; untreated, 66%). This was reflected in the significantly lower number of treated patients transfused [300 IU kg(-1), 20% (P< 0.001); 150 IU kg(-1), 45% (P< 0.05); untreated, 59%]. Epoetin alpha was well-tolerated, and there was no evidence of sustained, clinically significant, hypertension. In summary, epoetin alpha is effective and well-tolerated in maintaining Hb level and reducing transfusion requirement in patients undergoing cyclic chemotherapy for SCLC.

Very low birth weight births at non-NICU hospitals: the role of sociodemographic, perinatal, and geographic factors

PURPOSE

The purpose of this study was to assess the extent of variation in the percentage of very low birth weight (VLBW) infants born at perinatal Level 1 hospitals (no Neonatal Intensive Care Unit [NICU]) across California's nine geographic Perinatal regions. The role of sociodemographic, perinatal, and geographic factors was also assessed.

METHODS

Multivariate analysis of California birth certificate files between 1989 and 1993, for 24,094 live-born infants weighing between 500 and 1499 gm, was conducted to identify factors associated with delivery at a Level 1 hospital. Analyses specific for race and ethnicity were also conducted for Hispanic, African American, and white cohorts.

RESULTS

In the 5-year study period, 1989 through 1993, 10.5% (24,094) of all live-born VLBW infants were delivered in Level 1 hospitals. Significant variation across regions was evident, ranging from a regional low of 3.1% to a high of 24.3%. After controlling for multiple factors, the odds of delivering at a Level 1 hospital were decreased for African Americans and South East Asians and increased in Hispanic women as compared with white non-Hispanic women. For all women, less then adequate prenatal care, living in a 50% to 75% urban zip code, and living greater then 25 miles from the nearest NICU significantly increased the odds of VLBW delivery at a Level 1 hospital. For Hispanics, teen pregnancy and having two or more prior infant deaths increased the odds, whereas Medi-Cal as the payer source for delivery and two or more pregnancy complications decreased the odds of a Level 1 VLBW delivery. After taking these factors into account, when compared with Los Angeles, the odds of inappropriate delivery site ranged from 0.37 to 2.75 across California's nine geographic perinatal regions. Of this variation, 78% could be accounted for by the percentage of total births that delivered at a region's Level 1 hospitals.

CONCLUSION

The overall state average of 10.5% deliveries of VLBW at Level 1 hospitals, although close to the 10% national objective for the year 2000, did not indicate the wide variation seen across California's nine geographic regions. Risk-adjusted regional differences in the likelihood of inappropriate delivery site for the high-risk VLBW infants suggest that reaching the Healthy People 2000 objective will require further strengthening of California's perinatal regional networks, especially in those regions where a high percentage of total births deliver at Level 1 hospitals.

Chemotherapy in advanced ovarian cancer: four systematic meta-analyses of individual patient data from 37 randomized trials. Advanced Ovarian Cancer Trialists' Group

The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients.

The coordinate regulation of DNA synthesis and suppression of apoptosis is differentially regulated by the liver growth agents, phenobarbital and methylclofenapate

The coordinate regulation of DNA synthesis and suppression of apoptosis was investigated in a rat hepatocyte cell culture system which supports high level induction of DNA synthesis by the peroxisome proliferator, methylclofenapate (MCP) (Plant, N.J. et al., 1998, Carcinogenesis, 19, 925-931). The peroxisome proliferators are hepatocyte mitogens in chemically defined media: glucocorticoid-induced PPARalpha is linked to peroxisome proliferator mitogenesis (Plant, N.J. et al., 1998, Carcinogenesis, 19, 925-932). Phenobarbital (PB) induced moderate induction of DNA synthesis (200-300% of control), but the peak of induction was 40 h after treatment. In hepatocytes that had undergone DNA synthesis, PB increased the proportion of binucleates by 200-300%. Both PB and MCP were able to suppress apoptosis in a dose-dependent manner, while the endogenous mitogen epidermal growth factor failed to suppress apoptosis. The suppression of apoptosis by MCP was reversible; withdrawal of MCP led to rapid induction of apoptosis. The presence of hydrocortisone is required for suppression of apoptosis by peroxisome proliferators, but not for PB. MCP failed to suppress apoptosis in primary cultures of guinea-pig hepatocytes. Comparison of the stability of hepatocytes labelled with bromodeoxyuridine (BrdUrd) and [3H]thymidine revealed that approximately 40% of cells labelled with BrdUrd were lost over a period of 14 days, whereas cells labelled with thymidine remained stable over this period. Hepatocytes were therefore treated with MCP, labelled with [3H]thymidine, maintained for 14 days, and peroxisome proliferator withdrawn. While the apoptotic index in unlabelled cells was 1.7%, no apoptosis was detected in labelled cells. In order to compare the mechanism of suppression of apoptosis, hepatocytes were cultured in the presence of either PB or MCP for 14 days. When MCP was substituted for PB in cells cultured in the presence of PB, the monolayer was maintained, but when PB was used to replace MCP in cells cultured in the presence of MCP, the monolayer of hepatocytes degenerated rapidly. The results demonstrate mechanistic differences in the coordinate regulation of cell growth and apoptosis in hepatocytes by PB and MCP.

Molecular basis of non-responsiveness to peroxisome proliferators: the guinea-pig PPARalpha is functional and mediates peroxisome proliferator-induced hypolipidaemia

The guinea pig does not undergo peroxisome proliferation in response to peroxisome proliferators, in contrast with other rodents. To understand the molecular basis of this phenotype, the peroxisome proliferator activated receptor alpha (PPARalpha) from guinea-pig liver was cloned; it encodes a protein of 467 amino acid residues that is similar to rodent and human PPARalpha. The guinea-pig PPARalpha showed a high substitution rate: maximum likelihood analysis was consistent with rodent monophyly, but could not exclude rodent polyphyly (P approximately 0.06). The guinea-pig PPARalpha cDNA was expressed in 293 cells and mediated the induction of the luciferase reporter gene by the peroxisome proliferator, Wy-14,643, dependent on the presence of a peroxisome proliferator response element. Moreover the PPARalpha RNA and protein were expressed in guinea-pig liver, although at lower levels than in a species which is responsive to peroxisome proliferators, the mouse. To determine whether the guinea-pig PPARalpha mediated any physiological effects, guinea pigs were exposed to two selective PPARalpha agonists, Wy-14, 643 and methylclofenapate; both compounds induced hypolipidaemia. Thus the guinea pig is a useful model for human responses to peroxisome proliferators.

The peroxisome proliferators are hepatocyte mitogens in chemically-defined media: glucocorticoid-induced PPAR alpha is linked to peroxisome proliferator mitogenesis

Peroxisome proliferator-induced mitogenesis is believed to play a role in hepatocarcinogenesis, but it has not been possible to demonstrate high level induction of DNA synthesis by peroxisome proliferators in cultured hepatocytes. We now show that four structurally dissimilar peroxisome proliferators (methylclofenapate, Wy-14 643, tetradecyl-3-thia acetic acid and clofibrate) cause high level induction of DNA synthesis in primary cultures of rat hepatocytes, routinely 7-9 fold above control, with up to 29% of cells undergoing S-phase. Peroxisome proliferators induce DNA synthesis rapidly, with maximal response 24 h after dosing [compared with 48 h for epidermal growth factor (EGF)]; indeed, peroxisome proliferators were mitogenic in a chemically defined medium, i.e. with no added exogenous growth factors. EGF-treated hepatocytes that had undergone DNA synthesis comprised 23% binucleated cells, whereas hepatocytes induced into S-phase by peroxisome proliferators contained only 3% binucleated cells, demonstrating a distinct response of hepatocytes to peroxisome proliferators and EGF. The presence of a glucocorticoid was essential for peroxisome proliferator-induced DNA synthesis, but not for EGF-induced DNA synthesis, demonstrating that the requirement for glucocorticoids is selective for peroxisome proliferators. Hydrocortisone was shown to induce the expression of peroxisome proliferator activated receptor-alpha (PPAR alpha), and we propose that it is the glucocorticoid-induced expression of PPAR alpha that is essential for peroxisome proliferator mitogenesis. This in vitro system provides a powerful tool for investigating the mechanism and role of peroxisome proliferator-induced mitogenesis in liver growth and carcinogenesis.

A novel murine P-450 gene, Cyp4a14, is part of a cluster of Cyp4a and Cyp4b, but not of CYP4F, genes in mouse and humans

Genomic clones for Cyp4a12 and a novel member of the murine Cyp4a gene family were isolated. The novel gene, designated Cyp4a14, has a GC rich sequence immediately 5' of the transcription start site, and is similar to the rat CYP4A2 and CYP4A3 genes. The Cyp4a14 gene spans approximately 13 kb, and contains 12 exons; sequence similarity to the rat CYP4A2 gene sequence falls off 300 bp upstream from the start site. In view of the known sex-specific expression of the rat CYP4A2 gene, the expression and inducibility of Cyp4a14 was examined. The gene was highly inducible in the liver when mice were treated with the peroxisome proliferator, methylclofenapate; induction levels were low in control animals and no sex differences in expression were observed. By contrast, the Cyp4a12 RNA was highly expressed in liver and kidney of control male mice but was expressed at very low levels in liver and kidney of female mice. Testosterone treatment increased the level of this RNA in female liver slightly, and to a greater extent in the kidney of female mice. In agreement with studies on the cognate RNA, expression of Cyp4a12 protein was male-specific in the liver of control mice and extremely high inducibility of Cyp4a10 protein, with no sex differences, was also demonstrated. In view of the overlapping patterns of inducibility of the three Cyp4a genes, we investigated whether the three genes were co-localized in the genome. Two overlapping yeast artificial chromosome (YAC) clones were isolated, and the three Cyp4a genes were shown to be present on a single YAC of 220 kb. The Cyp4a genes are adjacent to the Cyp4b1 gene, with Cyp4a12 most distant from Cyp4b1. The clustering of these two gene subfamilies in the mouse was replicated in the human, where the CYPA411 and CYP4B1 genes were present in a single YAC clone of 440 kb. However, the human CYP4F2 gene was mapped to chromosome 19. Phylogenetic analysis of the CYP4 gene families demonstrated that CYP4A and CYP4B are more closely related than CYP4F.

Mediastinal epithelioid hemangioendothelioma in a patient with type IV Ehlers-Danlos syndrome: a case report and review of the literature

Ehlers-Danlos syndrome (EDS) is a collection of inherited connective tissue disorders with at least 10 types, differentiated on clinical and genetic grounds. Malignancy has been described only rarely in association with the syndrome. Epithelioid hemangioendothelioma (EH) is a rare endothelial tumor, which displays clinical behavior intermediate between that of hemangioma and angiosarcoma. A case report of a 50-year-old man with type IV EDS who was extensively investigated for several years for multiple mediastinal nerve palsies and chest pain. Magnetic resonance imaging (MRI) demonstrated an anterior mediastinal mass, which at biopsy showed EH. Subsequent metastatic spread to liver and lungs is unique among reported cases of mediastinal EH. The patient experienced significant symptomatic improvement from external beam radiotherapy (RT) to the mediastinum. After metastatic disease developed, multiagent chemotherapy was administered, but without response. The literature is reviewed regarding treatment of EH and the potential problems associated with EDS. Although there appears to be no etiological association between EDS and EH, the connective tissue disease clearly contributed to a delay in diagnosis and raised concerns regarding RT tolerance. The potential predisposition to aggressive tumor invasion remains a possibility. In addition, mediastinal EH has the potential to metastasize, and in this case demonstrated resistance to a broad range of chemotherapy agents.

Fatal pulmonary toxicity resulting from treatment with gemcitabine

BACKGROUND

Pulmonary toxicity reported with gemcitabine is usually mild and self-limiting. The authors report a series of three patients who had life-threatening pulmonary toxicity after receiving gemcitabine.

METHODS

The three patients presented to two major teaching hospitals with significant pulmonary dysfunction while receiving gemcitabine. Case data were obtained from patient records. A review of the literature was done to seek reports of pulmonary toxicity with gemcitabine and cytosine arabinoside (ara-C).

RESULTS

The common features of the respiratory illnesses of the three patients in this study were tachypnea, marked hypoxemia, and an interstitial infiltrate on chest radiograph consistent with pulmonary edema. There was no evidence of underlying heart disease in any patient. In addition, there was no evidence of infection, metabolic causes, or lymphangitic carcinomatosis to explain the clinical findings. Two patients died, and postmortem examination confirmed acute RDS (respiratory distress syndrome), whereas in the third patient a transbronchial biopsy showed interstitial pneumonitis. These findings were consistent with drug-induced pulmonary toxicity. Diuretics and corticosteroids were useful measures for treating the patients' symptoms, and one patient survived after gemcitabine was withdrawn.

CONCLUSIONS

These three cases of acute RDS may be the result of a capillary leak phenomenon due to treatment with gemcitabine, as observed in patients given intermediate dose and high dose ara-C, a drug similar in structure and metabolism to gemcitabine. The authors suggest caution in repeated administration of gemcitabine to patients who develop unexplained noncardiogenic pulmonary edema. Withdrawing gemcitabine and administering corticosteroids and diuretics may help to avert a fatal outcome.

Skeletal muscle ischemia-reperfusion causes transitory increase in microvascular protein permeability

The aim of this study was to determine whether the length of ischemia in skeletal muscle influences the return of normal microvascular permeability during reperfusion in addition to influencing the size of the initial changes. In anesthetized rabbits, the transvascular clearance of labeled albumin was measured in the gastrocnemius and soleus muscles during the first, second, third, or fourth hour of reperfusion after 1, 2, 3, or 4 h of ischemia. The size of the increases in albumin clearance, tissue water, and myeloperoxidase activity during the first hour of reperfusion was dependent on the length of ischemia. The return of the albumin clearance to control values during the fourth hour of reperfusion was independent of the length of ischemia. Tissue water, extravascular mass of native albumin, and myeloperoxidase activity remained elevated during the 4 h of reperfusion. After 4 h of ischemia, the solvent-drag reflection coefficient for albumin was significantly less than control during the first hour of reperfusion. The value during the fourth hour of reperfusion was not significantly different from control. These results suggest that the inflammatory mediators producing a change in permeability are washed out of the microvasculature during the first few hours of reperfusion.

Australian multicentre phase II trial of paclitaxel in women with metastatic breast cancer and prior chemotherapy

OBJECTIVE

To determine the efficacy and safety of paclitaxel given as a three-hour infusion in patients with metastatic breast cancer which had progressed despite hormonal therapy and/or chemotherapy.

DESIGN AND SETTING

Multicentre phase it trial undertaken in five major centres or hospitals in Sydney, Melbourne and Adelaide.

PATIENTS AND METHODS

50 patients with clinically or radiologically measurable or evaluable metastatic breast cancer recruited between March and July 1993. All had received prior chemotherapy, with subsequent disease progression.

INTERVENTION

Paclitaxel (Anzatax, Faulding) was given at a dose of 175 mg/m2 intravenously over three hours every three weeks for up to nine courses.

MAIN OUTCOME MEASURES

Response rate (partial or complete); duration of progression-free survival; duration of survival; and adverse reactions.

RESULTS

Patients had a median age of 51 years; 62% had received at least two prior drug regimens for metastatic breast cancer and 48% had anthracycline-resistant tumours. A median of six paclitaxel courses was given per patient. Overall response rate was 18% (95% confidence interval [95% CI], 9%-31%), with complete responses in four patients (8%). In patients with anthracycline-resistant tumours, response rate was 25% (95% CI, 10%-47%). Response was not influenced by extent of prior treatment. Estimated median progression-free survival was 4.1 months (95% CI, 3.2-6.0 months) and estimated median survival was 6.3 months (95% CI, 6.2-10.3 months). Treatment was well tolerated, with neutropenia the major toxic effect.

CONCLUSIONS

Paclitaxel (three-hour infusion) has significant activity in heavily pretreated patients with metastatic breast cancer, including anthracycline-resistant tumours.

Patterns of alternative medicine use by cancer patients

OBJECTIVE

To assess the patterns of alternative medicine use in patients of a public hospital oncology unit, and to compare patients' experience of alternative with conventional medicine.

DESIGN AND SETTING

Self-administered questionnaire survey of cancer patients attending specialist consulting rooms at the Royal North Shore Hospital and the Oncology Outpatient Clinic at Port Macquarie Base Hospital during August 1995.

PARTICIPANTS

507 patients attended the clinics; 335 (66%) returned questionnaires, of which 319 (62%) were sufficiently complete for analysis.

MAIN OUTCOME MEASURES

Expectations of and satisfaction with both conventional and alternative treatment, use of alternative treatment, and patient characteristics associated with this use.

RESULTS

Expectations of and satisfaction with both conventional and alternative treatment were very high. Alternative treatments (most commonly dietary and psychological methods) were used by 21.9% of patients. Median annual cost of alternative therapy was $530, with most patients reporting "value for money". Younger age and being married were positively associated, and satisfaction with conventional treatment was negatively associated, with alternative medicine use; 40% of patients did not discuss alternative medicine with their physician.

CONCLUSIONS

A significant proportion of cancer patients use one or more forms of alternative therapy. The use of alternative therapy may reflect on deficiencies in the current standard of care.

Selective effect of high arterial pressure in hypertension upon inhibition of cGMP versus cAMP mediated vascular relaxation

We tested the hypothesis as to whether elevated arterial pressure in hypertension alters cGMP, or cAMP, mediated vasorelaxation. Relaxation to nitroglycerin and isoproterenol was determined in isolated aortic rings from one-kidney, one clip hypertensive (1K1C), coarctation hypertensive (CH) and normotensive control (C) rats. Thoracic aortas from 1K1C and CH rats, as well as abdominal aortas from 1K1C rats, but not abdominal aortas from CH rats were exposed chronically (4-6 weeks) to elevated arterial pressure. Sensitivity of rings with and without endothelium to nitroglycerin was suppressed significantly only in vessels exposed chronically to high arterial pressure. Impaired sensitivity to nitroglycerin in abdominal rings from 1K1C rats could not be abolished by exposure to 100 uM L-arginine, the substrate for production of NO by endothelial nitric oxide synthase, or 100 uM L-cysteine, the source of thiol groups required for the production of nitric oxide from nitroglycerin. Maximum relaxation to isoproterenol was impaired significantly in thoracic and abdominal rings, with and without endothelium, from 1K1C and CH rats. Relaxation to 8-bromo-cGMP and dibutyryl cAMP was similar in abdominal rings from all groups. We conclude that impaired vasorelaxation to nitroglycerin and isoproterenol in hypertension involves mechanisms prior to activation of vascular smooth muscle cGMP-dependent and cAMP-dependent protein kinase, respectively. Impaired cGMP, but not cAMP, mediated relaxation of aortas appears to result from their exposure to high arterial pressure per se. This effect does not appear to involve the vascular endothelium or vascular sources of thiols, but rather may reflect an effect of high arterial pressure to impair the ability of the artery to respond to nitric oxide derived from nitroglycerin.

Cloning and structure of delta-latroinsectotoxin, a novel insect-specific member of the latrotoxin family: functional expression requires C-terminal truncation

The venom of the black widow spider (BWSV) (Latrodectus mactans tredecimguttatus) contains several potent, high molecular mass (>110 kDa) neurotoxins that cause neurotransmitter release in a phylum-specific manner. The molecular mechanism of action of these proteins is poorly understood because their structures are largely unknown, and they have not been functionally expressed. This study reports on the primary structure of delta-latroinsectotoxin (delta-LIT), a novel insect-specific toxin from BWSV, that contains 1214 amino acids. delta-LIT comprises four structural domains: a signal peptide followed by an N-terminal domain that exhibits the highest degree of identity with other latrotoxins, a central region composed of 15 ankyrin-like repeats, and a C-terminal domain. The domain organization of delta-LIT is similar to that of other latrotoxins, suggesting that these toxins are a family of related proteins. The predicted molecular mass and apparent mobility of the protein (approximately 130 kDa) encoded in the delta-LIT gene differs from that of native delta-LIT purified from BWSV (approximately 100 kDa), suggesting that the toxin is produced by proteolytic processing of a precursor. MALDI-MS of purified native delta-LIT revealed a molecular ion with m/z+ of 110916 +/- 100, indicating that the native delta-LIT is 991 amino acids in length. When the full-length delta-LIT cDNA was expressed in bacteria the protein product was inactive, but expression of a C-terminally truncated protein containing 991 residues produced a protein that caused massive neurotransmitter release at the locust neuromuscular junction at nanomolar concentrations. Channels formed in locust muscle membrane and artificial lipid bilayers by the native delta-LIT have a high Ca2+ permeability, whereas those formed by truncated, recombinant protein do not.

An open multicentre study of tropisetron for cisplatin-induced nausea and vomiting

OBJECTIVES

(i) To assess the efficacy and tolerability of tropisetron when used for acute and delayed cisplatin-induced emesis. (ii) To investigate whether dexamethasone added to tropisetron improves the control of emesis for patients who do not achieve a complete response to tropisetron alone. (iii) To assess sex of the patient and alcohol intake as prognostic factors for nausea and vomiting.

DESIGN

A prospective open label phase II trial over one or two cycles of chemotherapy. Data collection was based on observed response and patients' self-reporting.

SETTING

Twenty Australian tertiary care hospitals in 1994.

PATIENTS

102 male and female patients from 18 to 75 years with histologically confirmed malignancy receiving their first chemotherapy containing > or = 50 mg/m2 cisplatin.

INTERVENTION

In Cycle 1 tropisetron 5 mg was given intravenously before chemotherapy on Day 1, then 5 mg orally before breakfast on Days 2 to 6. In Cycle 2, dexamethasone 20 mg intravenously on Day 1, then 8 mg orally on Days 2 to 6 could be added to tropisetron if a complete antiemetic response had not been achieved in Cycle 1.

MAIN OUTCOME MEASURES

Number of vomiting episodes and severity of nausea for 6 days after chemotherapy; severity of side effects; patient satisfaction with chemotherapy treatment; oestradiol levels in women; and past alcohol consumption in men and women.

RESULTS

(i) The complete response rate (CR) for acute emesis in Cycle 1 was 64% (95% confidence interval [CI], 54%-72%), with 84% (95% CI, 76%-90%) having < or = 2 vomits. The CR for delayed emesis was 24% (95% CI, 17%-32%). The CR for acute nausea was 56% (95% CI, 47%-66%), with 97% (95% CI, 91%-99%) having < or = 2 nausea episodes. The CR for delayed nausea was 21% (95% CI, 14%-30%). Seventy-one patients received Cycle 2. The main side effects were headache (20 patients) and constipation (16 patients). The control of acute emesis was rated as "good" or "very good" by 68% of investigators; 85% rated the tolerability of treatment as "good" or "very good". Treatment was rated as "very satisfactory" or "satisfactory" by 52% of patients. (ii) The CR for acute emesis with dexamethasone added was 78% (95% CI, 64%-88%). (iii) Women with lower oestradiol levels had better control of emesis, although this difference was not statistically significant. Chronic alcohol intake and binge drinking were strongly associated with a complete acute antiemetic response.

CONCLUSIONS

Tropisetron was effective for acute cisplatin-induced emesis; adding dexamethasone enhanced this response. Both single and combined therapy had less effect on delayed emesis. The impact of alcohol on control of emesis is a chronic rather than acute phenomenon which requires prospective testing.

Long-term follow-up of a randomised trial of combined chemoradiotherapy induction treatment, with and without maintenance chemotherapy in patients with small cell carcinoma of the lung

The toxicity and efficacy of concomitant chemotherapy and radiotherapy as induction therapy was evaluated in patients with previously untreated small cell carcinoma of the lung (SCLC), and in responding patients the value of maintenance chemotherapy was examined. 202 patients received induction chemotherapy with cisplatin and etoposide (EP), in combination with cranial and local radiotherapy. 85 patients (42%) developed grades III and IV myelosuppression, the main toxicity of induction treatment. Of the 154 responding patients, 129 were randomised to maintenance chemotherapy with vincristine, doxorubicin and cyclophosphamide (VAC) or no further treatment. The response rate for the limited disease patients (LD) was 87%, 62% achieving a complete response (CR) and the response rate for extensive disease patients (ED) was 68%, with 26% achieving a CR. 17 patients (11%) completed 10 courses of maintenance chemotherapy. 32 patients (57%) developed grade III and IV neutropenia. Median survival for all patients was 53 weeks (LD, 70 weeks; ED, 42.5 weeks). There was no significant difference in overall survival (OS) or disease-free survival (DFS) in the two randomisation arms. This study shows that EP combined with radiotherapy is an effective induction regimen in SCLC. Maintenance chemotherapy with VAC is not associated with increased survival but has significant toxicity after such induction treatment.

Phase II trial of a 3-hour infusion of paclitaxel in previously untreated patients with advanced non-small-cell lung cancer

PURPOSE

To determine the antitumor activity and toxicity of paclitaxel administered as a 3-hour infusion in patients with advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Fifty-one patients with advanced measurable or assessable NSCLC and performance status 0 to 2 who had not received prior chemotherapy were treated with paclitaxel 175 mg/m2 over 3 hours with premedication. Cycles were repeated every 3 weeks for a maximum of nine cycles. Most patients had prior radiotherapy (57%), extrathoracic metastatic disease (65%), and measurable disease (75%). Twenty-two percent had previously untreated stage III disease.

RESULTS

The objective response rate was five of 51 (10%; 95% confidence interval, 3% to 21%). No subgroup with a higher response rate could be identified. There were no complete responses (CRs) and all responses lasted less than 5 months. Treatment was well tolerated with brief World Health Organization (WHO) grade IV neutropenia in only 16% of patients. Grade III/IV myalgia/athralgia occurred in 22% of patients. No significant hypersensitivity reactions occurred.

CONCLUSION

The antitumor activity of this dose and schedule appears inferior to that reported in previously published phase II trials in NSCLC that used higher doses of paclitaxel infused over 24 hours, although confidence intervals for response overlap. Determining the optimal dose and schedule for using paclitaxel in NSCLC requires further investigation, and these results should caution against using shorter infusions outside appropriate clinical trials.

Chromosomal localisation, inducibility, tissue-specific expression and strain differences in three murine peroxisome-proliferator-activated-receptor genes

Three murine peroxisome-proliferator-activated-receptor (PPAR) genes were localised to chromosome 15 (PPAR alpha), chromosome 17 (PPAR beta) and chromosome 6 (PPAR gamma). The expression of the three PPAR RNAs was determined using a specific RNase protection assay. In liver RNA, PPAR alpha was expressed at the highest level, with 20-fold lower levels of PPAR beta, and very low levels of PPAR gamma. The three PPAR RNAs showed no sex-specific differences in expression, and the levels of these transcripts were unaffected by treatment of mice with testosterone or the potent peroxisome proliferator, methylclofenapate. In agreement with this data, the level of PPAR alpha protein in liver was unchanged after treatment of mice with methylclofenapate. Investigation of the tissue-specific distribution revealed that the PPAR alpha RNA was expressed at highest levels in liver, to moderate levels in kidney and brown adipose tissue, and at low levels elsewhere. PPAR beta was expressed at moderate levels in liver, and lower levels in other tissues, including brown adipose tissue. In contrast, PPAR gamma RNA was expressed at low levels in liver or epididymal white adipose tissue and at very low levels elsewhere, but was expressed at high levels in brown adipose tissue. The tissue distribution of these receptors suggests an important role in lipid metabolism and toxicity for individual members of the PPAR family. The expression of PPAR alpha and PPAR beta RNAs was examined in 13 strains of mice, and the levels of expression varied within a fourfold range. Polymorphism in the size of PPAR alpha RNA from Swiss-Webster mice was detected, and shown to be due to a 2-bp mutation in the 3' non-coding region of PPAR alpha in Swiss Webster mice.

Noradrenergic vasorelaxation of porcine coronary arteries is enhanced by direct, acute exposure to 17 beta-estradiol

1. We tested whether responses of isolated coronary arteries to adrenergic agents are altered by overnight (18-22 hr) or acute exposure to physiological levels of 17 beta-estradiol. 2. Sensitivity to relaxation by norepinephrine (-log M ED50) was enhanced significantly in isolated arteries after acute exposure to 10(-9) M 17 beta-estradiol. Neither alpha-adrenergic contraction to norepinephrine, nor beta-adrenergic relaxation to isoproterenol was affected by acute exposure to 17 beta-estradiol. 3. Responses of coronary arteries to relaxation or contraction by norepinephrine, as well as relaxation by isoproterenol, were not altered by overnight incubation with 17 beta-estradiol or by removal of the endothelium. 4. We conclude that relaxation of coronary arteries by norepinephrine is enhanced by acute, direct exposure to physiological levels of 17 beta-estradiol. This enhancement does not result from effects of estradiol to suppress alpha-adrenergic contraction to norepinephrine or increase coronary beta-adrenergic receptor sensitivity.

Effect of chronic high pressure on transient and tonic vascular contractions to serotonin in hypertension

This study examined whether vascular contractions related to the extracellular or intracellular pools of calcium activated by serotonin are altered by high arterial pressure in chronic hypertension. Coarctation hypertensive (CH), sham normotensive control (C), and one-kidney, one-clip hypertensive rats (1K1C) were used. Tail systolic, carotid, and femoral arterial pressures were measured. Thoracic aortas from 1K1C and CH rats, as well as abdominal aortas from 1K1C rats, but not abdominal aortas from CH rats were exposed chronically to elevated arterial pressure. Isolated rings of thoracic and abdominal aortas from all groups were suspended in muscle baths for isometric force recordings. After cellular calcium depletion, dose-response curves to extracellular calcium, in the presence of 10(-5) mol/L serotonin, were unchanged in thoracic or abdominal aortas among the three groups. In the presence of submaximum levels of serotonin (2 x 10(-6) mol/L), thoracic and abdominal rings without endothelium and abdominal rings with endothelium from the three groups showed similar responses to extracellular calcium. Such responses were significantly depressed in thoracic rings with endothelium from CH and 1K1C rats. Transient contractions attributable to release of an intracellular calcium pool by 10(-5) mol/L serotonin were enhanced significantly in hypertensive thoracic and abdominal aortas from 1K1C rats, when the pool was loaded with 0.25, 0.5, 1.0, 2.0, or 4.0 mmol/L CaCl2, as well as in hypertensive thoracic aortas from CH rats when the pool was loaded with 1.0, 2.0, or 4.0 mmol/L CaCl2, but not in normotensive abdominal aortas from CH rats at any calcium-loading concentration. Similar results were observed in aortas from C, CH, and 1K1C rats loaded with 1.0 or 2.0 mmol/L CaCl2 and stimulated with 2 x 10(-6) mol/L serotonin. Endothelial removal had no effect on these calcium-release contractions in abdominal aortas from any group, but enhanced contractions in thoracic aortas of 1K1C rats. In rings loaded with 2.0 mmol/L CaCl2, 2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate inhibited contractions attributable to release of cellular calcium stores to a similar extent in C, CH, and 1K1C rats. This study suggests that serotonin-stimulated intracellular calcium-dependent aortic contractions are enhanced by elevated pressure in renal hypertensive rats.

Estrogen pretreatment directly potentiates endothelium-dependent vasorelaxation of porcine coronary arteries

We tested whether vasorelaxation of coronary arteries is altered after overnight (18-22 h) exposure to physiological levels of 17 beta-estradiol. Ring segments of left circumflex coronary artery from six female and six castrated male pigs were incubated in vials of sterile Dulbecco's modified Eagle's medium with 1 nM 17 beta-estradiol, 1 nM 17 beta-estradiol + 10 nM tamoxifen, 1 nM 17 alpha-estradiol, or estrogen vehicle (ethanol) under normoxic conditions in an O2-CO2 incubator at 37 degrees C for 18-22 h. Coronary rings, with and without endothelium, were then suspended in vessel baths for measurement of isometric force. Vasorelaxation responses to the calcium ionophore A-23187, ADP, and nitroglycerin were examined in the rings after prostaglandin synthesis blockade and precontraction with U-46619. Sensitivity to A-23187 (-log M concentration required for 50% of maximal relaxation) was significantly enhanced in coronary rings with endothelium from females and castrated males when rings were incubated with 17 beta-estradiol but not when they were incubated with 17 alpha-estradiol or 17 beta-estradiol+tamoxifen. Acute (2h) exposure of coronary arteries to 1 nM 17 beta-estradiol did not alter responses to A-23187. 17 beta-Estradiol (1 nM) was not itself directly vasoactive in coronary arteries with or without prior incubation with the steroid. Vasorelaxation of rings with and without endothelium to ADP and nitroglycerin was not significantly different among the treatment groups. Relaxation to A-23187, but not ADP, was abolished by removal of the endothelium or exposure to 100 microM NO2-L-arginine.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone presentation of non-Hodgkin's lymphoma: experience at the Royal North Shore Hospital, Sydney; highlighting primary bone lymphoma

BACKGROUND

Primary lymphoma of bone (PLB) is a rare form of extranodal lymphoma. Between 1975 and 1992 39 patients with lymphoma presenting in bone were seen at the Royal North Shore Hospital (RNSH), Sydney. Of these, 12 (31%) had truly localised disease (Stage IE).

AIMS

Patients were studied retrospectively to determine the prognostic significance of bony involvement per se versus involvement of a single bony site, and to determine the impact of treatment modality on outcome.

METHODS

The 39 patients were divided into three groups according to extent of disease; single osseous site (Stage IE), multifocal bone, and bone plus visceral and/or nodal disease. Kaplan-Meier survival curves were constructed, and five year actuarial survival stated. Cox regression analysis was used to determine hazard ratios. Overall survival was used as the end-point.

RESULTS

A trend for better survival was noted with Stage IE disease. Multifocal and disseminated disease appeared to have a poorer outcome when assessed by hazard ratio, with a value of 3 (95% CI 0.87-10.4; p = 0.08), compared to unifocal disease. Radiotherapy alone was as effective as combined modality treatment although patient numbers were too small for statistical confirmation.

CONCLUSIONS

The stage of lymphoma, rather than bony involvement per se, seems to have more prognostic importance. Radiotherapy alone offered equivalent results to combined modality treatment in this series.

Specificity and sensitivity of immunocytochemistry for detecting P-glycoprotein in haematological malignancies

AIMS

To determine the optimal working conditions of the alkaline phosphatase-antialkaline phosphatase (APAAP) method to establish a specific and sensitive assay for the detection of low numbers of MDR positive cells in patients with hematological malignancies.

METHODS

Three monoclonal antibodies (C-219, JSB-1, MRK-16) were used for the detection of P-glycoprotein (P-gp) in cell lines and in samples from 43 patients with haematological malignancies. The results of the APAAP method were compared with western blotting for specificity and sensitivity.

RESULTS

Excellent correlation was obtained between optimised APAAP and western blotting, except in the case of multiple myeloma. JSB-1 seemed to be the more useful monoclonal antibody for the APAAP which was more sensitive than western blotting in its ability to detect single P-gp positive cells.

CONCLUSIONS

Methods for P-gp detection, as defined by multidrug resistant (MDR) cell lines, are not necessarily optimal and specific for clinical samples and may lead to higher false positive and negative results, according to the conditions and the monoclonal antibodies used.

Isoproterenol decreases protein permeability in edematous isolated rabbit lungs: estimation of PS and sigma

The objective of the present study was to determine whether the ability of the beta-adrenergic agonist isoproterenol to attenuate pulmonary edema occurs via a permeability and/or hemodynamic mechanism. In isolated perfused rabbit lungs, the restrictive property of the vascular barrier to the movement of fluid and protein was assessed by measurements of the capillary filtration coefficient (Kf) and the transvascular clearance of 125I-labeled albumin, respectively. Regression analysis of albumin clearance vs. transvascular fluid flux was performed to estimate the permeability-surface area product (PS) and the reflection coefficient (sigma) by use of the linear or nonlinear flux equation. Arterial, capillary, and venous pressures and resistances, weight gain, and the wet-to-dry weight ratio were also assessed. Isoproterenol (8 ng.ml-1.min-1) attenuated the arachidonic acid (4 mg)-induced increases in fluid flux, wet-to-dry weight ratio, albumin clearance, and PS and the decrease in sigma. Isoproterenol had no effect on the increase in Kf, and there was no correlation between capillary pressure and fluid flux in any of the four groups. Regression analysis revealed that the non-linear flux equation provided estimates of PS and sigma that more accurately described the statistical differences in albumin clearance among the groups studied than the linear flux equation. These findings demonstrate that isoproterenol attenuated the increased transvascular flux of albumin in edematous lungs by modifying the protein permeability of the vascular barrier.