A Common Path: Magnetic Resonance Imaging of Müllerian and Wolffian Duct Anomalies.

PURPOSE OF REVIEW: This review summarizes the pathway of Mullerian and Wolffian duct development, anomalies that result from disruptions to this pathway, and the characteristics on advanced imaging that identify them. RECENT FINDINGS: In-office evaluation for reproductive anomalies is usually inadequate for the diagnosis of congenital reproductive anomalies. Magnetic resonance imaging (MRI) has usurped invasive diagnostic methods including laparoscopy, hysteroscopy, and vasography as the new gold standard. Because of its superior soft-tissue delineation and the availability of advanced functional sequences, MRI offers a sophisticated method of distinguishing reproductive anomalies from one another, characterizing the degree of defect severity, and evaluating for concomitant urogenital anomalies non-invasively and without radiation exposure to the patient. Congenital anomalies of the Mullerian and Wolffian duct can be incredibly nuanced, requiring prompt and accurate diagnosis for management of infertility. Definitive diagnosis should be made early with MRI.

Respiratory Viral Infections and Infection Prevention Practices Among Women With Acute Respiratory Illness During Delivery Hospitalizations During the 2019-2020 Influenza Season.

BACKGROUND: We conducted a cross-sectional study of pregnant women with acute respiratory illness during delivery hospitalizations during influenza season to describe clinical testing for respiratory viruses and infection prevention practices. METHODS: Women had nasal swabs tested for influenza and other respiratory viruses. Among 91 enrolled women, 22 (24%) had clinical testing for influenza. RESULTS: Based on clinical and study testing combined, 41 of 91 (45%) women had samples positive for respiratory viruses. The most common virus was influenza (17 of 91, 19%); 53% (9 of 17) of influenza virus infections were identified through study testing alone. Only 16% of women were on droplet precautions. CONCLUSIONS: Peripartum respiratory infections may be underrecognized.

How Accurate Is Oncologist Knowledge of Fertility Preservation Options, Cost, and Time in Female Adolescents and Young Adults?

Purpose: Often cited barriers to fertility preservation (FP) among female adolescent and young adult (AYA) cancer patients include cost and time. We hypothesized that oncologists overestimate the time and costs required for female FP. Methods: We distributed an electronic survey to physicians in oncology-related departments. The survey assessed the knowledge and utilization of gonadotoxic therapies, FP options and requirements, and FP referral patterns. Student's t, Fisher's exact, ANOVA, and Wilcoxon signed-rank tests were used for continuous variables as appropriate; the chi-squared test was used for categorical variables. Results: Among respondents who reported prescribing gonadotoxic agents to AYAs (n = 38), 79% reported often/always discussing FP options, while only half referred to a reproductive specialist often/always. A smaller proportion of pediatric oncologists discussed FP often/always (p = 0.04) and most referred <25% of patients to a reproductive specialist; however, the majority of other specialists referred ≥75% of patients to a reproductive specialist (p = 0.001). While most respondents accurately estimated the time required to complete FP, the majority overestimated the cost of an FP procedure. Knowledge of FP options was inconsistent, with 63.2% reporting that suppression of the hypothalamic-pituitary-ovarian-axis is an option for FP, with 82.6% of these classifying it as standard of care. Conclusions: With variation across specialties, most oncology specialists prescribing gonadotoxic therapies for AYA females discuss FP, while a smaller proportion refer patients for FP. Despite relative accuracy in estimating the time required for FP, they overestimate costs of FP. Educational curricula related to FP are necessary across oncology specialties, especially pediatric oncology.

Mechanism of OMP decarboxylation in orotidine 5'-monophosphate decarboxylase.

Despite extensive experimental and theoretical studies, the detailed catalytic mechanism of orotidine 5'-monophosphate decarboxylase (ODCase) remains controversial. In particular simulation studies using high level quantum mechanics have failed to reproduce experimental activation free energy. One common feature of many previous simulations is that there is a water molecule in the vicinity of the leaving CO2 group whose presence was only observed in the inhibitor bound complex of ODCase/BMP. Various roles have even been proposed for this water molecule from the perspective of stabilizing the transition state and/or intermediate state. We hypothesize that this water molecule is not present in the active ODCase/OMP complex. Based on QM/MM minimum free energy path simulations with accurate density functional methods, we show here that in the absence of this water molecule the enzyme functions through a simple direct decarboxylation mechanism. Analysis of the interactions in the active site indicates multiple factors contributing to the catalysis, including the fine-tuned electrostatic environment of the active site and multiple hydrogen-bonding interactions. To understand better the interactions between the enzyme and the inhibitor BMP molecule, simulations were also carried out to determine the binding free energy of this special water molecule in the ODCase/BMP complex. The results indicate that the water molecule in the active site plays a significant role in the binding of BMP by contributing approximately -3 kcal/mol to the binding free energy of the complex. Therefore, the complex of BMP plus a water molecule, instead of the BMP molecule alone, better represents the tight binding transition state analogue of ODCase. Our simulation results support the direct decarboxylation mechanism and highlight the importance of proper recognition of protein bound water molecules in the protein-ligand binding and the enzyme catalysis.

Site-specific OH attack to the sugar moiety of DNA: a comparison of experimental data and computational simulation.

Little computational or experimental information is available on site-specific hydroxyl attack probabilities to DNA. In this study, an atomistic stochastic model of OH radical reactions with DNA was developed to compute relative OH attack probabilities at individual deoxyribose hydrogen atoms. A model of the self-complementary decamer duplex d(CCAACGTTGG) was created including Na(+) counter ions and the water molecules of the first hydration layer. Additionally, a method for accounting for steric hindrance from nonreacting atoms was implemented. The model was then used to calculate OH attack probabilities at the various C-H sites of the sugar moiety. Results from this computational model show that OH radicals exhibit preferential attack at different deoxyribose hydrogens, as suggested by their corresponding percentage solvent-accessible surface areas. The percentage OH attack probabilities for the deoxyribose hydrogens [1H(5')+2H(5'), H(4'), H(3'), 1H(2')+2H(2'), H(1')] were calculated as approximately 54.6%, 20.6%, 15.0%, 8.5% and 1.3%, respectively, averaged across the sequence. These results are in good agreement with the latest experimental site-specific DNA strand break data of Balasubramanian et al. [Proc. Natl. Acad. Sci. USA 95, 9738-9742 (1998)]. The data from this stochastic model suggest that steric hindrance from nonreacting atoms significantly influences site-specific hydroxyl radical attack probabilities in DNA. A number of previous DNA damage models have been based on the assumption that C(4') is the preferred site, or perhaps the only site, for OH-mediated DNA damage. However, the results of the present study are in good agreement the experimental results of Balasubramanian et al. in which OH radicals exhibit preferential initial attack at sugar hydrogen atoms in the order 1H(5')+2H(5') > H(4') > H(3') > 1H(2')+2H(2') > H(1').

Toward a computational description of nitrile hydratase: studies of the ground state bonding and spin-dependent energetics of mononuclear, non-heme Fe(III) complexes.

The metal coordination and spin state of the Fe(III) center in nitrile hydratase (NHase) has stimulated the synthesis of model complexes in efforts to understand the reactivity and spectroscopic properties of the enzyme. We report density functional theory (DFT) calculations on a number of Fe(III) complexes that have been prepared as models of the NHase metal center, together with others having similar ligands but different ground state spin multiplicities. Our results suggest that a DFT description of specific spin configurations in these systems does not suffer from significant amounts of spin contamination. In particular, B3LYP calculations not only reproduce the observed spin state preferences of these Fe(III) complexes but also predict spin-dependent structural properties consistent with those expected on the basis of ligand field models. An analysis of the natural bond orbital (NBO) transformation of the Kohn-Sham wave functions has enabled quantitation of the overall contribution to covalency of ligand-to-metal sigma-donation and pi-donation, and metal-to-ligand pi-back-bonding in these Fe(III) complexes at their BLYP-optimized geometries. Although sulfur ligands are the primary source of covalency in the Fe(III) complexes, our quantitative analysis suggests that hyperbonding between metal-bound nitrogens and an Fe-S bond represents a mechanism by which Fe-N covalency may arise. These studies establish the computational methodology for future theoretical investigations of the NHase Fe(III) center.