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David Elder

Publications and source records attributed to David Elder.

10 recordsLinked to original sources

Preferential involvement of CX chemokine receptor 4 and CX chemokine ligand 12 in T-cell migration toward melanoma cells.

Our previous analysis of the role of chemokines in T lymphocyte trafficking toward human tumor cells revealed the migration of a melanoma patient's cytotoxic T lymphocytes (CTL) toward autologous tumor cells, resulting in tumor cell apoptosis, in an organotypic melanoma culture. CTL migration was mediated by CX chemokine receptor (CXCR) 4 expressed by the CTL and CX chemokine ligand (CXCL) 12 secreted by the tumor cells, as evidenced by blockage of CTL migration by antibodies to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. Here, we present the results of T cell migration in one additional melanoma patient and T cell and tumor cell analyses for CXCR4 and CXCL12 expression, respectively, in 12 additional melanoma patients, indicating the preferential role of CXCR4 and CXCL12 in CTL migration toward melanoma cells. These studies add to the increasing body of evidence suggesting that CXCL12 is a potent chemoattractant for T cells.

Cell Line, Tumor↗

Surveillance of Australian workplace Based Respiratory Events (SABRE): notifications for the first 3.5 years and validation of occupational asthma cases.

AIMS: In Australia, the SABRE programme, a notification scheme, has been established to collect incidence data on occupational lung disease. This paper reports the first 3.5 years of this scheme and the results of an occupational asthma validation study. METHODS: A notification form is mailed regularly to thoracic physicians and occupational physicians in the Australian states of Victoria and Tasmania, who use this to report new cases of occupational lung disease. The validation study was performed by a blinded panel of two doctors, who reviewed information extracted from the medical files of a sample of reported cases of occupational asthma. RESULTS: A total of 520 diagnoses were reported. The mean (+/- SD) age of the 448 patients notified was 55.7 +/- 16.2 years. There were 394 (88%) males and 54 females. The most common single condition was asthma for which the most common causative agent was wood dust. However, the most commonly reported agent overall was asbestos. The validation study of occupational asthma found only fair agreement (kappa = 0.4) between the panel and notifying doctors. However, agreement was better (kappa = 0.5) when the analysis was restricted to those cases where the reporting doctor considered the likelihood of the diagnosis was high. CONCLUSIONS: Occupational asthma is the most common occupational respiratory condition reported, which suggests increasing importance for this disease over more traditional forms of occupational lung disease. The validation study suggests that such schemes should restrict notifications only to those cases where the likelihood of the diagnosis is considered high.

Asbestos↗

Thin primary cutaneous malignant melanoma: a prognostic tree for 10-year metastasis is more accurate than American Joint Committee on Cancer staging.

PURPOSE: The majority of invasive primary melanomas are thin (< or = 1.00 mm). Since the current staging system imperfectly predicts outcome in patients with such lesions, we sought to develop a more effective classification scheme to better identify both patients at high risk of metastasis who are candidates for further staging and therapy and those with little risk. PATIENTS AND METHODS: This prospective cohort study included 884 patients who had thin invasive melanomas. A tree-structured analysis of 10-year metastasis was used to develop a new classification scheme. RESULTS: The overall 10-year metastasis rate was 6.5% (95% CI, 4.8% to 8.1%). The prognostic tree defined four risk groups: high-risk: men with vertical growth phase (VGP) lesions that had mitotic rates (MRs) greater than 0, and for whom the 10-year metastasis rate was 31% (22% to 42%; n = 90); moderate-risk: women with VGP lesions that had MRs greater than 0 and for whom the rate was 13% (9% to 18%; n = 136); low-risk: patients with VGP lesions that had MR of 0 for whom the rate was 4% (2% to 7%; n = 247); and minimal-risk: patients with invasive lesions without VGP for whom the rate was 0.5% (0% to 1.2%; n = 411). Survival curves differed significantly among the four groups (P <.001). CONCLUSION: Growth phase, mitotic rate, and sex are important prognostic factors for patients with thin melanomas, and they identify subgroups at substantial risk for metastasis. After validation in other populations, the proposed prognostic tree will be useful in the design of clinical trials and clinical management.

Aged↗

Overview of the status and applications of capillary electrophoresis to the analysis of small molecules.

The status of capillary electrophoresis (CE) in the analysis of small molecules is reviewed and summarised with the illustrative use of recent literature references. Examples are cited in this review which demonstrate that CE is now a recognised and established technique in many industries, law courts and government regulatory agencies. Each of the principal areas of CE application in small molecule analysis are covered in sections which highlight the recent developments and possibilities within that area. Application areas include the analysis of pharmaceuticals, agrochemicals, chiral separations, and forensics is covered. This is an update to a previous review article [J. Chromatogr. A 856 (1999) 443] and covers papers published between 1999 and 2002. Technical developments and improvements, such as the advent of capillary array instrumentation for increased sample throughput, and improved detection options are described. Overall it is concluded that CE has become a recognised and established technique in many areas and is still within a period of development of both instrumentation and application which will continue to expand usage.

Carbohydrates↗

Desmoplastic neurotropic melanoma of the head and neck: the role of radiation therapy.

BACKGROUND: Desmoplastic neurotropic melanoma (DNM) is an uncommon cutaneous melanoma variant with pronounced neurotropism. In contrast to ordinary melanomas, locoregional recurrences are common and distant metastasis are uncommon in patients with DNM. Local control with surgery and radiation therapy may assume a more important role in this variant of melanoma. We present a case of an unresectable skull base recurrence of DNM that was controlled using radiation therapy alone and review the literature. METHODS: Case report with 36-month follow-up. RESULTS: The patient is a 68-year-old with multiple recurrences of a DNM that originated on the forehead. After extensive surgery, including total parotidectomy and temporal bone resection, the patient had an unresectable recurrence of the skull base develop. This was treated with definitive radiation therapy, resulting in a complete response. The patient has had no evidence of recurrence at 3 years. CONCLUSIONS: DNM is a locally aggressive type of melanoma with a high risk of local recurrence that can be radioresponsive. The incidence of distant metastasis is low, so aggressive treatment to control local disease is warranted. This may include surgery plus adjuvant radiation therapy or definitive radiotherapy for unresectable recurrences.

Aged↗

Melanoma-stroma interactions: structural and functional aspects.

Cutaneous melanomas are notorious for their tendency to metastasise. Because the tumour microenvironment plays an important part in tumour development and progression, we review the structural and functional aspects of interactions between melanoma and the stroma. We emphasise fibrovascular patterns (both in uveal and cutaneous melanoma), cellular and extracellular composition of the stroma, and the molecules involved. Also, we discuss functional interactions, focusing on melanoma-fibroblast cross-talk by soluble factors and by direct cell-cell contact. On the basis of recent findings we propose that involvement of fibroblasts in melanoma-stromagenesis occurs through different stages: recruitment, activation, and conversion to myofibroblasts, or differentiation to fibrocytes. We reason that this involvement is topographically linked to different areas in and around the tumour, and hypothesise that stromal activation, as seen in tumor ulceration or immunological regression in melanoma, stimulates tumour progression.

Cell Communication↗

Ribozymes: the hairpin and Varkud ribozymes are related.

The hairpin ribozyme of plant virusoids and the Varkud ribozyme from a retroplasmid of fungal mitochondria show notable similarities in sequence and secondary structure. Some more distant inter-relationships appear to exist between this pair, the viroid/virusoid hammerhead and the hepatitis delta ribozyme.

Endoribonucleases↗