Attract and deter: a dual role for pyrrolizidine alkaloids in plant–insect interactions

Pyrrolizidine alkaloids (PAs) are the major defense compounds of plants in the Senecio genus. Here I will review the effects of PAs in Senecio on the preference and performance of specialist and generalist insect herbivores. Specialist herbivores have evolved adaptation to PAs in their host plant. They can use the alkaloids as cue to find their host plant and often they sequester PAs for their own defense against predators. Generalists, on the other hand, can be deterred by PAs. PAs can also affect survival of generalist herbivores. Usually generalist insects avoid feeding on young Senecio leaves, which contain a high concentration of alkaloids. Structurally related PAs can differ in their effects on insect herbivores, some are more toxic than others. The differences in effects of PAs on specialist and generalists could lead to opposing selection on PAs, which may maintain the genetic diversity in PA concentration and composition in Senecio species

Pathology Case Study: Left Breast Mass

This is a case study presented by the University of Pittsburgh Department of Pathology in which an 80-year-old woman presents to the hospital with "a single, palpable, irregular mass in the left breast." Visitors are given the gross and microscopic descriptions, including images, and are given the opportunity to diagnose the patient. This is an excellent resource for students in the health sciences to familiarize themselves with using patient history and laboratory results to diagnose disease. It is also a helpful site for educators to use to introduce or test student learning in gynecologic pathology

Pathology Case Study: Skin Lesion

This is a case study presented by the University of Pittsburgh Department of Pathology in which a woman with uterine endometrioid adenocarcinoma with focal squamous differentiation arising in complex atypical hyperplasia. Visitors are given both the microscopic and gross descriptions, including images, and are given the opportunity to diagnose the patient. This is an excellent resource for students in the health sciences to familiarize themselves with using patient history and laboratory results to diagnose disease. It is also a helpful site for educators to use to introduce or test student learning in dermatologic pathology

Unusual Ovarian Stromal Tumor with Radiation Changes Mimicking Carcinoma

<p>Radiation-related changes including fibrosis, nuclear enlargement, hyperchromasia and cytoplasmic vacuolization may alter the appearance of normal ovarian tissue and ovarian tumors. We describe radiation-related changes in ovarian stromal neoplasm with mixed features of sclerosing stromal tumor and fibrothecoma. The right ovarian mass was discovered in a 38 year-old woman with past history of invasive squamous cell carcinoma of the cervix treated with cone biopsy and brachytherapy. The low power architecture of cellular pseudolobules and small sheets of tumor cells with scattered hyaline plaques was consisted with the pattern of combined sclerosing stromal tumor and fibrothecoma. However, the presence of severe cytologic atypia, as well as clear cell and signet ring differentiation and arrangements of tumor cells in single files and nests, raised a possibility of primary or metastatic carcinoma. The tumor cells were positive for calretinin, vimentin, inhibin, and WT1 and negative for AE1/3, cytokeratin 7 and 20, CD99, estrogen and progesterone receptors, mammaglobin, chromogranin, and S100 protein. Based on the results of immunostains and a subsequently provided history of radiation, a diagnosis of sex cord stromal tumor with mixed fibrothecoma and sclerosing stromal differentiation was made. Radiation-related atypia and fibrosis in sex cord stromal tumor may create a pattern mimicking carcinoma and therefore, in the presence of unusual histology, the use of immunohistochemistry is recommended.</p