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M D Mason

Publications and source records attributed to M D Mason.

62 records · Page 4Linked to original sources

Chronic complicated osteomyelitis of the lower extremity: evaluation with MR imaging.

Preoperative magnetic resonance (MR) imaging examinations were performed with a 1.5-T superconducting magnet in 14 patients who had extensive deformities of the bones and soft tissues of the lower extremities due to previous trauma, surgery, and chronic infection. This retrospective study assessed the diagnostic performance of MR imaging in determining the presence and extent of active bone and soft-tissue infections. The presence and extent of active osteomyelitis were confirmed by reviewing the clinical, surgical, histologic, and microbiologic records of all patients. Of the 14 MR imaging examinations, 11 were true-positive, two were true-negative, one was false-positive, and none was false-negative. In the indium scans obtained in this group of patients, five were true-positive, three were true-negative, none was false-positive, and three were false-negative. In two amputated extremities, close correlation was found between the extent of disease seen on surgical and pathologic examination and that demonstrated by MR imaging, which could delineate the course of sinus tracts. MR imaging was therefore helpful in assessing the activity of chronic complicated osteomyelitis and beneficial in surgical planning for these patients.

Adult↗

School matron.

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Organization and Administration↗

Factors affecting presentation and delay in patients with testicular cancer: results of a qualitative study.

A qualitative study was undertaken with men treated for testicular tumours, to ascertain how they interpreted their symptoms and the factors which influenced a decision to consult a physician. The research was undertaken with six men who had been diagnosed as having testicular tumours. Interviews were also conducted with four wives and one mother. The findings showed that giving men information on testicular cancer may not guarantee early presentation. Symptoms were not generally attributed to cancer and the one patient who practised self-examination had delayed seeking help for 6 months. The extent to which symptoms affected the patient's lifestyle was also a factor in the decision-making process, as was the checking of symptoms with other family members. Wives were often pivotal in persuading men to seek help. The discovery of testicular symptoms produced emotional responses which included embarrassment and fear of both cancer and castration. There was evidence of strong feelings of masculine identity bound up with the appearance of 'normal' genitals. Provider-delay was identified in four cases and was associated with misattribution of symptoms by physicians and the failure to initiate specialist referral. Delay was under-recorded in the hospital notes in all cases where presentation was not immediate.

Adult↗

Preparation of human ovarian cancer ascites-derived exosomes for a clinical trial.

Despite initial response to chemotherapy, at least 50% of ovarian cancer patients will relapse within 18 months. Progression-free survival is related to tumour infiltration with cytotoxic T lymphocytes (CTL). We recently demonstrated that CD8+ T cell responses to recall antigens improve following tumour response to chemotherapy. Vaccination designed to expand CTL, specific for tumour-associated antigens, may be a means of improving outcome. We are planning a clinical trial in advanced ovarian cancer patients undergoing chemotherapy using a combination of a Toll-like receptor 3 (TLR3) agonist and tumour-associated ascites-derived exosomes. Tumour-derived exosomes are a potential source of tumour antigens able to induce CD8+ T cell responses when loaded on mature dendritic cells (DC). DC maturation can be achieved with Toll-like receptor (TLR) agonists, such as the GMP-grade synthetic double stranded RNA, poly[I]:poly[C12U] (Ampligen) which is a TLR-3 agonist. Here, we describe the development of a method suitable for the preparation of GMP-grade exosomes from the ascites fluid of ovarian cancer patients, and the methods used for the molecular and immunological characterisation of these exosomes preceding their use in a clinical trial.

Ascites↗

Radiotherapy versus single-dose carboplatin in adjuvant treatment of stage I seminoma: a randomised trial.

BACKGROUND: Adjuvant radiotherapy is effective treatment for stage I seminoma, but is associated with a risk of late non-germ-cell cancer and cardiovascular events. After good results in initial studies with one injection of carboplatin, we undertook a large randomised trial to compare the approaches of radiotherapy with chemotherapy in seminoma treatment. METHODS: Between 1996 and 2001, 1477 patients from 70 hospitals in 14 countries were randomly assigned to receive radiotherapy (para-aortic strip or dog-leg field; n=904) or one injection of carboplatin (n=573; dose based on the formula 7x[glomerular filtration rate+25] mg), at two trial centres in the UK and Belgium. The primary outcome measure was the relapse-free rate, with the trial powered to exclude absolute differences in 2-year rates of more than 3%. Analysis was by intention to treat and per protocol. This trial has been assigned the International Standard Randomised Controlled Trial Number ISRCTN27163214. FINDINGS: 885 and 560 patients received radiotherapy and carboplatin, respectively. With a median follow-up of 4 years (IQR 3.0-4.9), relapse-free survival rates for radiotherapy and carboplatin were similar (96.7% [95% CI 95.3-97.7] vs 97.7% [96.0-98.6] at 2 years; 95.9% [94.4-97.1] vs 94.8% [92.5-96.4] at 3 years, respectively; hazard ratio 1.28 [90% CI 0.85-1.93], p=0.32). At 2 years' follow-up, the absolute differences in relapse-free rates (radiotherapy-chemotherapy) were -1.0% (90% CI -2.5 to 0.5) by direct comparison of proportions, and 0.9% (-0.5 to 3.0) by a hazard-ratio-based approach. Patients given carboplatin were less lethargic and less likely to take time off work than those given radiotherapy. New, second primary testicular germ-cell tumours were reported in ten patients allocated irradiation (all after para-aortic strip field) and two allocated carboplatin (5-year event rate 1.96% [95% CI 1.0-3.8] vs 0.54% [0.1-2.1], p=0.04). One seminoma-related death occurred after radiotherapy and none after carboplatin. INTERPRETATION: This trial has shown the non-inferiority of carboplatin to radiotherapy in the treatment of stage I seminoma. Although the absence of disease-related deaths and preliminary data indicating fewer second primary testicular germ-cell tumours favour carboplatin use, these findings need to be confirmed beyond 4 years' follow-up.

Adult↗

E-cadherin and associated molecules in the invasion and progression of prostate cancer.

Prostatic carcinoma is the most common type of male cancer found in the Western world and its distant metastasis becomes a life threatening event in tumour bearing patients. However, the biology of prostate cancer and metastasis is poorly understood. We review the progress made in the last decade on the molecular and cellular biology of cell-cell adhesion molecules in the invasion and progression of prostate cancer, with emphasis being placed on E-cadherin and its associated molecules.

Cadherins↗

Cell-cell adhesion molecules and their associated proteins in bladder cancer cells and their role in mitogen induced cell-cell dissociation and invasion.

Three bladder cell lines (EJ138, RT112/84 and T24/83) were used to examine the expression of E-cadherin, desmoglein, their associated proteins and their role in cell-cell dissociation and invasion using hepatocyte growth factor/scatter factor (HGF/SF). Both immunocytochemistry and Western blotting revealed that RT112/84 cells expressed high levels of E-cadherin, alpha-, beta-, and gamma-catenins. However, there was no expression of E-cadherin and very low levels of alpha- and beta-catenin expression detected in both EJ138 and T24/83 cells. In contrast, all three cell lines were found to express desmoglein, desmoplakin and c-Met. An in vitro invasion assay showed that both EJ138 and T24/83 cells were highly invasive, however, RT112/84 cells were found to have very limited invasion. Invasion of RT112/84 cells was significantly increased by inclusion of either antibody to E-cadherin or motogen (HGF/SF) in the culture medium. This did not appear to be the case for EJ138 and T24/83 cells. Using immunoprecipitation, HGF/SF induced tyrosine phosphorylation of beta-catenin but not desmoplakin. It is concluded that E-cadherin plays a stronger role than desmosomal cadherin in the control of the in vitro invasion of bladder cancer cells. Activation of beta-catenin and subsequent dysfunction of E-cadherin may be a key mechanism in the induction of invasion by the motogen, HGF/SF.

Animals↗