Assessing anchor damage on coral reefs: a case study in selection of environmental indicators

Because environmental conservation can remove scarce natural resources from competing uses, it is important to gain support for conservation programs by demonstrating that management actions have been effective in achieving their goals. One way to do this is to show that selected significant environmental variables (indicators) vary between managed and unmanaged areas or change over time following implementation of a management regime. However, identifying indicators that reflect environmental conditions relevant to management practices has proven difficult. This paper focuses on developing a framework for choosing indicators in a coral reef habitat. The framework consisted of three phases: (1) information gathering to identify candidate variables; (2) field-testing candidate variables at sites that differ in intensity of human activity, thus identifying potential indicators; and (3) evaluating potential indicators against a set of feasibility criteria to identify the most useful indicators. To identify indicators suitable to measure the success of a management strategy to reduce anchor damage to a coral reef, 24 candidate variables were identified and evaluated at sites with different intensities of anchoring. In this study, measures that reflected injuries to coral colonies were generally more efficient than traditional measures of coral cover in describing the effects of anchoring. The number of overturned colonies was identified as the single most useful indicator of coral reef condition associated with anchoring intensities. The indicator selection framework developed here has the advantages of being transparent, cost efficient, and readily transferable to other types of human activities and management strategies.

Perineural spread by squamous carcinomas of the head and neck: a morphological study using antiaxonal and antimyelin monoclonal antibodies

Perineural spread has been demonstrated histologically in 65/180 (36%) major surgical resections for squamous carcinomas of the head and neck; the incidence in a smaller necropsy series was 18/20 (90%). Perineural infiltration was observed most commonly in the vicinity of carcinomas arising in the buccal cavity (31/63, 50%) and, at all sites, it was most commonly encountered near tumours less than or equal to 2.5 cm in diameter. Perineural spread near cervical node metastases was, by contrast, uncommon in the surgical series. Tumour within perineural spaces tends to be concentrated at the margin of the nerve and shows only limited extension inwards, but cells may track upwards and downwards within the spaces. Distant spread for greater than 2 cm is unusual, and interval sampling of involved nerves in necropsy material indicates that most perineural tumour cells are confined to the distal 1 cm of the affected nerve. Infiltrated nerves regularly show varying degrees of myelin and axonal degeneration, probably anoxic in origin, and segmental infarction of nerve trunks was observed in three patients. Fine changes in axons and myelin have been regularly demonstrated with two monoclonal antibodies, and the use of these new reagents is described.

Monoclonal antibodies to the human mammary gland. II. Distribution of determinants in breast carcinomas

A range of primary and metastatic human breast carcinomas has been examined with respect to the staining by four monoclonal antibodies which were raised to the human milk fat globule membrane. Within the normal breast the luminal epithelial cells expressing the antigens detected by the monoclonal antibodies were heterogeneous in their distribution. The heterogeneity was not only confined to single cells, but also to regions within the breast. The breast carcinomas also expressed the antigens in a variable manner. Morphological differentiation and functional differentiation, defined by the monoclonal antibodies, were not invariably coincident. Lymph node metastases gave similar results to the primary carcinomas. The monoclonal antibodies have revealed a heterogeneity, with respect to surface antigenic expression, within the normal and neoplastic breast epithelium. This cellular heterogeneity of breast carcinomas, may have significant prognostic and therapeutic implications in the management of primary breast cancer.

Monoclonal antibodies to the human mammary gland. I. Distribution of determinants in non-neoplastic mammary and extra mammary tissues

Mouse monoclonal antibodies have been raised to the human milk fat globule membrane. The distribution of the antigens detected by four of the antibodies has been examined in formalin-fixed paraffin-embedded human tissues by light microscopic immunocytochemistry. The four antibodies stain lactating breast and normal resting breast. Two exclusively stain the luminal membranes of breast epithelial cells. A third antibody stains in addition the lateral membranes of duct epithelial cells. The fourth antibody stains both epithelial and myoepithelial cells. None of the antibodies is breast specific, nor do they stain every epithelial cell within the breast. Instead, each antibody reveals a complex and heterogeneous distribution of staining throughout the normal tissues. Within the breast, the staining by a given antibody is usually segmental and conforms to secretory units and their associated ducts. Similarly heterogeneous patterns of staining are also observed in the extramammary normal tissues. Despite the apparent morphological identity between breast epithelial cells when examined by conventional light microscopy, the hitherto unrecognised "functional" heterogeneity, which has been revealed by the monoclonal antibodies could have importance in understanding the biology of the normal breast and the pathology of breast cancer.