Fertility After Endometrial Intraepithelial Neoplasia and Early Endometrial Cancer: Ovulation Induction May Shorten Time to Conception.

The purpose of this study was to determine whether utilization of assisted reproductive technology following clearance of endometrial intraepithelial neoplasia (EIN) or early endometrial cancer (EC) shortens time to conception (TTC) and reduces recurrence. Patients aged 18 to 45 with EIN or early EC who achieved pathologic response following progesterone treatment were identified via retrospective chart review. Study groups included patients who pursued ovulation induction (OI), in vitro fertilization (IVF), and spontaneous pregnancy. Primary outcomes were TTC and recurrence rate. Three hundred forty-six charts were reviewed, with 86 patients meeting inclusion criteria and 53 attempting pregnancy. Of those 53 patients, 11 became pregnant and seven had a live birth. Median times to pregnancy were 183 days for IVF, 54 days for OI, and 347 days for spontaneous conception (p < 0.05). No differences were seen in recurrence or progression based on attempted pregnancy method, nor with duration of fertility treatment. Forty-two of 86 patients (49%) were lost to follow-up. For patients with a history of treated EIN or EC, OI may decrease TTC. Larger prospective studies are needed to definitively answer this question. Although no differences in recurrence or progression were identified, the significant loss to follow-up rate in this study is concerning and warrants further investigation.

DEPC modification of the CuA protein from Thermus thermophilus.

The CuA center is the initial electron acceptor in cytochrome c oxidase, and it consists of two copper ions bridged by two cysteines and ligated by two histidines, a methionine, and a carbonyl in the peptide backbone of a nearby glutamine. The two ligating histidines are of particular interest as they may influence the electronic and redox properties of the metal center. To test for the presence of reactive ligating histidines, a portion of cytochrome c oxidase from the bacteria Thermus thermophilus that contains the CuA site (the TtCuA protein) was treated with the chemical modifier diethyl pyrocarbonate (DEPC) and the reaction followed through UV-visible, circular dichroism, and electron paramagnetic resonance spectroscopies at pH 5.0-9.0. A mutant protein (H40A/H117A) with the non-ligating histidines removed was similarly tested. Introduction of an electron-withdrawing DEPC-modification onto the ligating histidine 157 of TtCuA increased the reduction potential by over 70 mV, as assessed by cyclic voltammetry. Results from both proteins indicate that DEPC reacts with one of the two ligating histidines, modification of a ligating histidine raises the reduction potential of the CuA site, and formation of the DEPC adduct is reversible at room temperature. The existence of the reactive ligating histidine suggests that this residue may play a role in modulating the electronic and redox properties of TtCuA through kinetically-controlled proton exchange with the solvent. Lack of reactivity by the metalloproteins Sco and azurin, both of which contain a mononuclear copper center, indicate that reactivity toward DEPC is not a characteristic of all ligating histidines.