1-IODOPENTANE, EXPERIMENTS AND CALCULATIONS

The rotational spectra of two conformers, GAA and AAA, of 1-iodopentane have been recorded using both Fourier transform microwave cavity and chirp spectrometers. Iodine has a large nuclear electric quadrupole coupling tensor, $\boldsymbol{\chi}$, and is heavy enough to require a relativistic calculation for {\it{ab initio}} field gradient calculations. We will present a comparison of the experimental results, a calculation involving a clever scaling of the $\boldsymbol{\chi}$ tensor,\footnote{W.C. Bailey and F.M. Gonzalez {\it{J. Mol. Spectro.}}, {\bf{651-653}}, 689-695 (2003)} and a direct relativistic {\it{ab initio}} calculation.\footnote{L. Cheng, J. Gauss, {\it{J. Chem. Phys.}}, {\bf{134}}, 244112 (2011)

A MICROWAVE STUDY OF THREE BROMINE-CONTAINING MOLECULES: CBr2F2, AgBr, and H2 AgBr

In preparation for our FTMW study of the complex between hydrogen and silver bromide, H$_{2}$ AgBr, we have investigated the microwave spectra of our source of bromine, dibromodifluoromethane, CBr$_2$F$_{2}$. Previous sources of bromine to produce AgBr proved either too damaging to the instrumentation in the long term (Br$_{2}$), or did not produce enough AgBr to be useful (CHBr$_{3}$). In addition, silver bromide, originally studied by Hoeft, Lovas, Tiemann, and Torring in 1971,\footnote{J. Hoeft, F. J. Lovas, E. Tiemann, T. Torring, Z. Naturforsch. 25a, 35 (1970).} and remeasured by Evans and Gerry in 2000,\footnote{C. J. Evans, M. C. L. Gerry, J. Chem. Phys. 112, 1321 (2000).} was remeasured once more. We plan to produce H$_{2}$ AgBr, using laser ablation of a silver rod within a supersonic expansion of an argon carrier gas containing H$_{2}$ and CBr$_{2}$F$_{2}$. This is part of our ongoing study of hydrogen complexed with metal halides which include H$_{2}$ CuF,\footnote{D. J. Frohman, G. S. Grubbs II, Z. Yu, S. E. Novick, Inorg. Chem. 52, 816 (2013).} H$_{2}$ AgCl,\footnote{G. S. Grubbs II, D. A. Obenchain, H. M. Pickett, S. E. Novick, J. Chem. Phys. 141, 114306 (2014).} and H$_{2}$ AuCl.\footnote{D. A. Obenchain, G. S. Grubbs II, H. M. Pickett, S. E. Novick, J. Chem. Phys. 146, 204302 (2017).} These molecules are “models” of the molecular hydrogen storage in the cavities of metal organic frameworks (MOFs)

Microwave spectra of a potential four-fold internal rotor, phenylsulfur pentafluoride

We present the microwave spectra of the fourth molecule containing the four-fold rotor –SF$_5$, phenylsulfur pentafluoride, c-C$_6$H$_5$–SF$_4$–F (PhSPF). The first three molecules in this series were vinylsulfur pentafluoride (VSPF), propen-1-ylsulfur pentafluoride (PSPF) and buten-1-ylsulfur pentafluoride (BSPF). VSPF exhibited splitting into the A, E, and B torsional states with 10’s of MHz between the torsional transitions. PSPF exhibited the torsional splitting with 10’s of kHz between transitions. BSPF exhibited no torsional splitting. Likewise, PhSPF shows no torsional splitting in the spectra. This phenomenon is mostly explained by the differences in the values of the four-fold barrier to internal rotation, V$_4$, in this series of molecules

Molecular Imaging of Autoimmune Diseases and Inflammation

Molecular imaging methods allow the noninvasive detection and localization of specific molecules. Agents that report on molecular disease biomarkers can be used to diagnose and monitor disease. Many inflammatory diseases have molecular signatures within altered tissues. Although tissue biopsy is still the gold standard for detecting these signatures, several molecular imaging markers have been developed. Pharmacologic agents that block specific immune molecules have recently entered the clinic, and these drugs have already transformed the way we care for patients with immune-mediated diseases. The use of immunomodulatory drugs is usually guided by clinical assessment of the patient's response. Unfortunately, clinical assessment may miss the signs of inflammation, and many of the serologic markers of immune-mediated diseases correlate poorly with the underlying inflammatory activity within target tissues. Molecular imaging methods have the potential to improve our ability to detect and characterize tissue inflammation. We discuss some of the molecular signatures of immune activation and review molecular imaging methods that have been developed to detect active tissue inflammation

Evaluation of common genetic variants in 82 candidate genes as risk factors for neural tube defects

<p>Abstract</p> <p>Background</p> <p>Neural tube defects (NTDs) are common birth defects (~1 in 1000 pregnancies in the US and Europe) that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., <it>MTHFR</it> rs1801133 (677 C > T) and <it>MTHFD1</it> rs2236225 (R653Q)) have been found to increase NTD risk. We hypothesized that variants in additional folate/B12 pathway genes contribute to NTD risk.</p> <p>Methods</p> <p>A tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents), including 301 cases and 341 Irish controls to perform case–control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects.</p> <p>Results</p> <p>Nearly 70 SNPs in 30 genes were found to be associated with NTDs at the p < 0.01 level. The ten strongest association signals (p-value range: 0.0003–0.0023) were found in nine genes (<it>MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1</it> and <it>T (Brachyury)</it>) and included the known NTD risk factor <it>MTHFD1</it> R653Q (rs2236225). The single strongest signal was observed in a new candidate, <it>MFTC</it> rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele). Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing.</p> <p>Conclusions</p> <p>To our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the stringency of correction are likely to have contributed to real associations failing to survive correction. We have produced a ranked list of variants with the strongest association signals. Variants in the highest rank of associations are likely to include true associations and should be high priority candidates for further study of NTD risk.</p