Implementation of a Survey to Reduce Urine Pregnancy Tests Prior to Gynecology Procedures in Primary Care

Excluding pregnancy in individuals prior to initiating contraception is important. The Pregnancy Reasonably Excluded Guide (PREG) uses twelve questions related to a patient’s reproductive history to effectively rule out pregnancy without administering a urine pregnancy screen, saving the patient both time and money. The PREG survey was given at Mayo Clinic in Rochester, MN, from 2015 to 2018 to all patients receiving an Intrauterine Device or Subdermal Implant. This study examined data from the 2018 collection year to determine if urine screening requests by providers were reduced from the pre-PREG data. It also determined whether urine tests were requested disproportionally for patients by their age range or type of contraceptive procedure. One-hundred sixty-eight women between the ages of 18 and 50 were included, with the majority identifying as white (84%) between the ages of 18 and 31 (54%). Using a Chi-square analysis, it was found that neither urine test by age (p=0.69) nor urine test by procedure (p=0.98) were significant. Urine tests were not requested more often for certain procedures or by patient age. However, the number of urine screens requested pre-PREG compared to the number requested post-PREG for the year 2018 was significant (P\u3c0.01). Through implementation of the PREG survey, urine pregnancy testing was drastically reduced and in turn, there were reduced costs to patients and the clinics

Selective inhibition of HIV-1 reverse transcriptase-associated ribonuclease H activity by hydroxylated tropolones

High-throughput screening of a National Cancer Institute library of pure natural products identified the hydroxylated tropolone derivatives β-thujaplicinol (2,7-dihydroxy-4-1(methylethyl)-2,4,6-cycloheptatrien-1-one) and manicol (1,2,3,4-tetrahydro-5-7-dihydroxy-9-methyl-2-(1-methylethenyl)-6H-benzocyclohepten-6-one) as potent and selective inhibitors of the ribonuclease H (RNase H) activity of human immunodeficiency virus-type 1 reverse transcriptase (HIV-1 RT). β-Thujaplicinol inhibited HIV-1 RNase H in vitro with an IC(50) of 0.2 μM, while the IC(50) for Escherichia coli and human RNases H was 50 μM and 5.7 μM, respectively. In contrast, the related tropolone analog β-thujaplicin (2-hydroxy-4-(methylethyl)-2,4,6-cycloheptatrien-1-one), which lacks the 7-OH group of the heptatriene ring, was inactive, while manicol, which possesses a 7-OH group, inhibited HIV-1 and E.coli RNases H with IC(50) = 1.5 μM and 40 μM, respectively. Such a result highlights the importance of the 2,7-dihydroxy function of these tropolone analogs, possibly through a role in metal chelation at the RNase H active site. Inhibition of HIV-2 RT-associated RNase H indirectly indicates that these compounds do not occupy the nonnucleoside inhibitor-binding pocket in the vicinity of the DNA polymerase domain. Both β-thujaplicinol and manicol failed to inhibit DNA-dependent DNA polymerase activity of HIV-1 RT at a concentration of 50 μM, suggesting that they are specific for the C-terminal RNase H domain, while surface plasmon resonance studies indicated that the inhibition was not due to intercalation of the analog into the nucleic acid substrate. Finally, we have demonstrated synergy between β-thujaplicinol and calanolide A, a nonnucleoside inhibitor of HIV-1 RT, raising the possibility that both enzymatic activities of HIV-1 RT can be simultaneously targeted

Crystal engineering of HIV-1 reverse transcriptase for structure-based drug design

HIV-1 reverse transcriptase (RT) is a primary target for anti-AIDS drugs. Structures of HIV-1 RT, usually determined at ∼2.5–3.0 Å resolution, are important for understanding enzyme function and mechanisms of drug resistance in addition to being helpful in the design of RT inhibitors. Despite hundreds of attempts, it was not possible to obtain the structure of a complex of HIV-1 RT with TMC278, a nonnucleoside RT inhibitor (NNRTI) in advanced clinical trials. A systematic and iterative protein crystal engineering approach was developed to optimize RT for obtaining crystals in complexes with TMC278 and other NNRTIs that diffract X-rays to 1.8 Å resolution. Another form of engineered RT was optimized to produce a high-resolution apo-RT crystal form, reported here at 1.85 Å resolution, with a distinct RT conformation. Engineered RTs were mutagenized using a new, flexible and cost effective method called methylated overlap-extension ligation independent cloning. Our analysis suggests that reducing the solvent content, increasing lattice contacts, and stabilizing the internal low-energy conformations of RT are critical for the growth of crystals that diffract to high resolution. The new RTs enable rapid crystallization and yield high-resolution structures that are useful in designing/developing new anti-AIDS drugs

The Hepatitis B Virus Ribonuclease H Is Sensitive to Inhibitors of the Human Immunodeficiency Virus Ribonuclease H and Integrase Enzymes

Nucleos(t)ide analog therapy blocks DNA synthesis by the hepatitis B virus (HBV) reverse transcriptase and can control the infection, but treatment is life-long and has high costs and unpredictable long-term side effects. The profound suppression of HBV by the nucleos(t)ide analogs and their ability to cure some patients indicates that they can push HBV to the brink of extinction. Consequently, more patients could be cured by suppressing HBV replication further using a new drug in combination with the nucleos(t)ide analogs. The HBV ribonuclease H (RNAseH) is a logical drug target because it is the second of only two viral enzymes that are essential for viral replication, but it has not been exploited, primarily because it is very difficult to produce active enzyme. To address this difficulty, we expressed HBV genotype D and H RNAseHs in E. coli and enriched the enzymes by nickel-affinity chromatography. HBV RNAseH activity in the enriched lysates was characterized in preparation for drug screening. Twenty-one candidate HBV RNAseH inhibitors were identified using chemical structure-activity analyses based on inhibitors of the HIV RNAseH and integrase. Twelve anti-RNAseH and anti-integrase compounds inhibited the HBV RNAseH at 10 μM, the best compounds had low micromolar IC50 values against the RNAseH, and one compound inhibited HBV replication in tissue culture at 10 μM. Recombinant HBV genotype D RNAseH was more sensitive to inhibition than genotype H. This study demonstrates that recombinant HBV RNAseH suitable for low-throughput antiviral drug screening has been produced. The high percentage of compounds developed against the HIV RNAseH and integrase that were active against the HBV RNAseH indicates that the extensive drug design efforts against these HIV enzymes can guide anti-HBV RNAseH drug discovery. Finally, differential inhibition of HBV genotype D and H RNAseHs indicates that viral genetic variability will be a factor during drug development. © 2013 Tavis et al

Mechanistic Investigations of Mandelate Racemase: The Electrophilic Catalysts

110 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1998.MR is a member of the enolase superfamily (Babbitt et al., 1996), which is a family of proteins which are both structurally and mechanistically related. All the family members have highly conserved metal ion ligands. Based on the homology to enolase, which requires two divalent metal ions, MR as well as other members of the enolase superfamily might require two metal ions. The stoichiometries of metal ion requirements for MR, muconate lactonizing enzyme (MLE), galactonate dehydratase (GalD) and glucarate dehydratase (GlucD) were determined. MR and MLE bind and require a single metal ion for activity. GalD and GlucD require two metals for activity and show inhibition at high metal ion concentrations with Mn\sp{2+}..U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Mechanistic Investigations of Mandelate Racemase: The Electrophilic Catalysts

110 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1998.MR is a member of the enolase superfamily (Babbitt et al., 1996), which is a family of proteins which are both structurally and mechanistically related. All the family members have highly conserved metal ion ligands. Based on the homology to enolase, which requires two divalent metal ions, MR as well as other members of the enolase superfamily might require two metal ions. The stoichiometries of metal ion requirements for MR, muconate lactonizing enzyme (MLE), galactonate dehydratase (GalD) and glucarate dehydratase (GlucD) were determined. MR and MLE bind and require a single metal ion for activity. GalD and GlucD require two metals for activity and show inhibition at high metal ion concentrations with Mn\sp{2+}..U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD