Background Polycystic ovary syndrome (PCOS) is a common endocrine disorder among women of reproductive age and a major cause of infertility; however, the pathophysiology of this syndrome is not fully understood. This can be addressed using appropriate animal models of PCOS. In this review, we describe rodent models of hormone‐induced PCOS that focus on the perturbation of the hypothalamic‐pituitary‐ovary (HPO) axis and abnormalities in neuropeptide levels. Methods Comparison of rodent models of hormone‐induced PCOS. Main findings The main method used to generate rodent models of PCOS was subcutaneous injection or implantation of androgens, estrogens, antiprogestin, or aromatase inhibitor. Androgens were administered to animals pre‐ or postnatally. Alterations in the levels of kisspeptin and related molecules have been reported in these models. Conclusion The most appropriate model for the research objective and hypothesis should be established. Dysregulation of the HPO axis followed by elevated serum luteinizing hormone levels, hyperandrogenism, and metabolic disturbance contribute to the complex etiology of PCOS. These phenotypes of the human disease are recapitulated in hormone‐induced PCOS models. Thus, evidence from animal models can help to clarify the pathophysiology of PCOS.

Background: TcdA and TcdB are the main virulence factors for Clostridium difficile infections. Results: X-ray crystallography, mass spectrometry, and size exclusion chromatography reveal the molecular basis of antibody recognition. Conclusion: Neutralizing antibodies do not directly block binding to known receptors, suggesting new mechanisms of neutralization. Significance: The molecular details of antibody recognition will assist with the development of novel therapeutics and diagnostics.

Individual finger position and external grip forces were investigated while subjects held cylindrical objects from above using circular precision grips. Healthy females (n = 11) and males (n = 15) lifted cylindrical objects of various weights (0.5, 1.0 and 2.0 kg), and varied diameters (5.0, 7.5 and 10.0 cm) using the 5-finger grip mode. The effects of 4-, 3- and 2-finger grip modes in the circular grip were also investigated. Individual finger position was nearly constant for all weights and for diameters of 5.0 and 7.5 cm. The mean angular positions for the index, middle, ring and little fingers relative to the thumb were 98 degrees, 145 degrees, 181 degrees, and 236 degrees, respectively. At the 10-cm diameter, the index and middle finger positions increased, while the ring and little finger positions decreased. There were no differences in individual finger position with regard to gender, hand dimension, or hand strength. Total grip force increased with weight, and at diameters greater or lesser than 7.5 cm. Total grip force also increased as the number of fingers used for grasping decreased. Although the contribution of the individual fingers to the total grip force changed with weight and diameter, the thumb contribution always exceeded 38% followed by the ring and little fingers, which contributed approximately 18-23% for all weights and diameters. The contribution of the index finger was always smallest (> or = 11%). There was no gender difference for any of the grip force variables. The effects of hand dimension and hand strength on the individual finger grip forces were subtle.

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