Premenstrual syndrome is a collection of heterogeneous symptoms that are attributed to hormonal fluctuations and that vary among individuals for unknown reasons. We propose that much of what is labeled "premenstrual syndrome" is part of a broader set of infectious illnesses that are exacerbated by cyclic changes in immunosuppression, which are induced by cyclic changes in estrogen and progesterone. This cyclic defense paradigm accords with the literature on cyclic exacerbations of persistent infectious diseases and chronic diseases of uncertain cause. Similar exacerbations attributable to hormonal contraception implicate hormonal alterations as a cause of these changes. The precise timing of these cyclic exacerbations depends on the mechanisms of pathogenesis and immunological control of particular infectious agents. Insight into these mechanisms can be obtained by a comparison of timing of menstrual exacerbations with the timing of exacerbations associated with pregnancy.

This study investigated whether sexually transmitted infections and lifestyle variables are associated with premenstrual syndrome (PMS) as well as particular manifestations commonly associated with PMS. Data were gathered from medical records of 500 regularly cycling women. The following infectious agents were investigated: human papillomavirus, Chlamydia trachomatis, Neisseria gonorrheae, Gardnerella vaginalis, Candida albicans, and Trichomonas vaginalis. Bivariate tests and multivariate logistic regressions were used to evaluate whether these pathogens were associated with headache, pain, nausea, and depression. Chlamydia trachomatis was significantly associated with premenstrual syndrome (PMS) and two common manifestations of PMS: depression and pain. Trichomonas vaginalis was significantly correlated with headache and Gardnerella vaginalis with nausea. None of the illness manifestations was significantly associated with the tested lifestyle variables: dietary calcium supplementation, alcohol and drug use, exercise, and smoking. These associations provide a basis for assessment of infectious causation of PMS and several manifestations of illness that are commonly associated with PMS.

Abstract

Project-based (research-driven) laboratory courses stimulate student involvement, improve critical thinking and initiate cooperative learning. To this end, a 7-week laboratory project was designed for a sophomore cell biology course to reinforce the fundamental relationship between genotype and phenotype using yeast alcohol dehydrogenase I (ADH1). Working in pairs, students used site-directed mutagenesis to create a H44R mutation in the ADH1 gene sequence inserted into a YEp13 shuttle vector. These plasmids were propagated in E. coli, sequenced, and reintroduced into a yeast strain expressing no ADH1 activity. The growth patterns on selective media were determined. As the mutation allows for growth in the presence of allyl alcohol, students make the connection between DNA sequence and protein function. Student performance was assessed with pre-and post-tests, with improvement observed across all learning objectives. In addition to meeting the learning outcomes, 98% of the students thought that this experience allowed them to see how the scientific process can encompass multiple techniques to answer a single question. Eighty-four percent of the students thought that this experience was more engaging than other lab experiences they have had. Our multi-week laboratory examining the phenotypic changes in yeast alcohol metabolism successfully developed students' understanding of the scientific process, knowledge of molecular techniques and the relationship of gene sequence to protein function in an engaging manner.