4 research outputs found
High Ki-67 expression is associated with prolactin secreting pituitary adenomas
Pituitary adenomas represent the third most common primary intracranial tumor in neurosurgical practice. To understand the biological behaviour of the pituitary adenomas previous studies have determined the tumor proliferation rate using monoclonal antibodies targeted against the Ki-67 antigen. The aim of this study was to correlate the Ki-67 index with hormonal profiles of pituitary adenomas. The study included 50 pituitary adenomas. For histopathologic evaluation, the sections were stained with routine hematoxylin and eosin method. Additional paraffin sections from each tumor were immunostained using primary antibodies against the following pituitary hormones: somatotropin (STH), prolactin (PRL), adrenocorticotrophic hormone (ACTH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). To detect the expression of Ki-67 we used a mouse anti-human monoclonal antibody (clone K2). The percentage of Ki-67 positive nuclei (Ki-67 labeling index) was assessed by counting approximately 1000 nuclei of the tumor cells at Ă400 magnification. Out of the 50 tumor samples, 31 (62%) pituitary adenomas showed proliferative activity, and the proliferation rate was variable in this group. The overall mean Ki-67 labeling index was 1.59 ± 1.47, ranging from 0.3% to 6.6%. In 5 cases, the Ki-67 index was >3%, all of them being prolactinomas. The Ki-67 index was higher in PRL-secreting adenomas (mean ± SD was 3.37 ± 1.80, range 0.9 - 6.6%). Our study provides the evidence that a higher Ki-67 value is associated with pituitary adenomas that secrete PRL (prolactinomas and mixed STH/PRL-secreting adenomas)
Governing Trade-Offs in Ecosystem Services and Disservices to Achieve HumanâWildlife Coexistence
Sustaining wildlife populations, which provide both ecosystem services and disservices, represents a worldwide conservation challenge. The ecosystem services and Ostrom\u27s socialâecological systems frameworks have been adopted across natural and social sciences to characterize benefits from nature. Despite their generalizability, individually they do not include explicit tools for addressing the sustainable management of many wildlife populations. For instance, Ostrom\u27s framework does not specifically address competing perspectives on wildlife, whereas the ecosystem services framework provides a limited representation of the social and governance context wherein such competing perspectives are embedded. We developed a unified socialâecological framework of ecosystem disservices and services (SEEDS) that advances both frameworks by explicitly acknowledging the importance of competing wildlife perspectives embedded in the social and governance contexts. The SEEDS framework emulates the hierarchical structure of Ostrom\u27s socialâecological systems, but adds subsystems reflecting heterogeneous stakeholder views and experiences of wildlifeâbased services and disservices. To facilitate operationalizing SEEDS and further broader analyses across humanâwildlife systems, we devised a list of variables to describe SEEDS subsystems, such as types and level of services and disservices, cost and benefit sharing, and social participation of stakeholders. Steps to implement SEEDS involve engaging local communities and stakeholders to define the subsystems, analyze interactions and outcomes, and identify leverage points and actions to remedy unwanted outcomes. These steps connect SEEDS with other existing approaches in socialâecological research and can guide analyses across systems or within individual systems to provide new insights and management options for sustainable humanâwildlife coexistence