Brief embryonic strychnine exposure in zebrafish causes long-term adult behavioral impairment with indications of embryonic synaptic changes

Zebrafish provide a powerful model of the impacts of embryonic toxicant exposure on neural development that may result in long-term behavioral dysfunction. In this study, zebrafish embryos were treated with 1.5 mM strychnine for short embryonic time windows to induce transient changes in inhibitory neural signaling, and were subsequently raised in untreated water until adulthood. PCR analysis showed indications that strychnine exposure altered expression of some genes related to glycinergic, GABAergic and glutamatergic neuronal synapses during embryonic development. In adulthood, treated fish showed significant changes in swimming speed and tank diving behavior compared to controls. Taken together, these data show that a short embryonic exposure to a neurotoxicant can alter development of neural synapses and lead to changes in adult behavior

Endometriosis – Morphology, Clinical Presentations and Molecular Pathology

Endometriosis is found predominantly in women of childbearing age. The prevalence of endometriosis is difficult to determine accurately. Laparoscopy or surgery is required for the definitive diagnosis. The most common symptoms are dysmenorrhea, dyspareunia, and low back pain that worsen during menses. Endometriosis occurring shortly after menarche has been frequently reported. Endometriosis has been described in a few cases at the umbilicus, even without prior history of abdominal surgery. It has been described in various atypical sites such as the fallopian tubes, bowel, liver, thorax, and even in the extremities. The most commonly affected areas in decreasing order of frequency in the gastrointestinal tract are the recto-sigmoid colon, appendix, cecum, and distal ileum. The prevalence of appendiceal endometriosis is 2.8%. Malignant transformation is a well-described, although rare (<1% of cases), complication of endometriosis. Approximately 75% of these tumors arise from endometriosis of the ovary. Other less common sites include the rectovaginal septum, rectum, and sigmoid colon. Unopposed estrogens therapy may play a role in the development of such tumors. A more recent survey of 27 malignancies associated with endometriosis found that 17 (62%) were in the ovary, 3 (11%) in the vagina, 2 (7%) each in the fallopian tube or mesosalpinx, pelvic sidewall, and colon, and 1 (4%) in the parametrium. Two cases of cerebral endometriosis and a case of endometriosis presenting as a cystic mass in the cerebellar vermis has been described. Treatment for endometriosis can be expectant, medical, or surgical depending on the severity of symptoms and the patient's desire to maintain or restore fertility

Strategic Party Government: Party Influence in Congress, 1789?2000

Why does the influence of Congressional parties fluctuate over time? Building on prevailing answers, we develop a model, Strategic Party Government, which highlights the electoral motives of legislative parties and the strategic interaction between parties. We test this theory using the entire range of House and Senate party behavior from 1789 to 2000 and find that the strategic behavior of parties complements members' preferences as an explanation for variation in party influence. Specifically, the strongest predictors of one party's voting unity are the unity of the opposing party and the difference between the parties in the preceding year. Moreover, we find strong links between party behavior in Congress and electoral outcomes: an increase in partisan influence on legislative voting has adverse electoral costs, while winning contested votes has electoral benefits