Phenolic compounds are generally believed to be key components of the oxidative defenses of plants against pathogens and herbivores. However, phenolic oxidation in the gut fluids of insect herbivores has rarely been demonstrated, and some phenolics could act as antioxidants rather than prooxidants. We compared the overall activities of the phenolic compounds in red oak (Quercus rubra) and sugar maple (Acer saccharum) leaves in the midgut fluids of two caterpillar species, Malacosoma disstria (phenolic-sensitive) and Orgyia leucostigma (phenolic-tolerant). Three hypotheses were examined: (1) ingested sugar maple leaves produce higher levels of semiquinone radicals (from phenolic oxidation) in caterpillar midgut fluids than do red oak leaves; (2) O. leucostigma maintains lower levels of phenolic oxidation in its midgut fluids than does M. disstria; and (3) phenolic compounds in tree leaves have overall prooxidant activities in the midgut fluids of caterpillars. Sugar maple leaves had significantly lower ascorbate: phenolic ratios than did red oak leaves, suggesting that phenolics in maple would oxidize more readily than those in oak. As expected, semiquinone radicals were at higher steady-state levels in the midgut fluids of both caterpillar species when they fed on sugar maple than on red oak, consistent with the first hypothesis. Higher semiquinone radical levels were also found in M. disstria than in O. leucostigma, consistent with the second hypothesis. Finally, semiquinone radical formation was positively associated with two markers of oxidation (protein carbonyls and total peroxides). These results suggest that the complex mixtures of phenolics in red oak and sugar maple leaves have overall prooxidant activities in the midgut fluids of M. disstria and O. leucostigma caterpillars. We conclude that the oxidative defenses of trees vary substantially between species, with those in sugar maple leaves being especially active, even in phenolic-tolerant herbivore species.
Objectives The support of the uterine cervix assessed in the clinic with Valsalva or cough and operating room (OR) with traction often differs. The objective of this study is to test the null hypothesis that the difference between preoperative and intraoperative values of POP-Q (Pelvic Organ Prolapse Quantification) point C is not related to prolapse size, and to determine if other factors exist that predict this difference. Methods This is a retrospective review of women who had a vaginal hysterectomy in the FPMRS (Female Pelvic Medicine and Reconstructive Surgery) division between 2005 and 2011 and had preoperative and intraoperative POP-Q point C recorded. A difference of 5 cm was established by a panel of urogynecologists as clinically significant. Student t-tests and chi-squared analyses were used and a logistic regression performed. Results There were 206 subjects included. The mean difference in point C between the two clinical settings was 3.5 cm. A difference of ≥5 cm was present in 33%. The mean difference in point C was larger for women with lesser stages of prolapse (stage 1: 5.8 cm, stage 2: 3.0 cm, stage 3/4: 1.4 cm, p<.001). A difference of ≥5 cm in point C was more often present in women with lesser stages of prolapse–70.3% of women with stage 1, 9.3% for stage 2 and 8.5% for stage 3 (p<0.001). Conclusions We reject our null hypothesis. A difference of ≥5 cm between POP-Q point C in the clinic and the operating room occurred more frequently in women with lesser stages of prolapse.
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