Exploration of Solid-State vs Solution-State Structure in Contact Ion Pair Systems: Synthesis, Characterization, and Solution-State Dynamics of Zinc Diphenyl Phosphate, [Zn{O2P(OPh)2}2], Donor-Base-Supported Complexes.

A family of zinc phosphate complexes supported by nitrogen donor-base ligands have been synthesized, and their molecular structures were identified in both the solid (X-ray crystallography) and solution state (DOSY NMR spectroscopy). [Zn{O2P(OPh)2}2]∞ (1), formed from the reaction of Zn[N(SiMe3)2]2 with HO(O)P(OPh)2 coordinates to donor-base ligands, i.e., pyridine (Py), 4-methylpyridine (4-MePy), 2,2-bipyridine (bipy), tetramethylethylenediamine (TMEDA), pentamethyldiethylenetriamine (PMDETA), and 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me3-TAC), to produce polymeric 1D structures, [(Py)2Zn{O2P(OPh)2}2]∞ (2) and [(4-MePy)2Zn{O2P(OPh)2}2]∞ (3), the bimetalic systems, [(Bipy)Zn{O2P(OPh)2}2]2 (4), [(TMEDA)Zn{O2P(OPh)2}2]2 (5), and [(Me3-TAC)Zn{O2P(OPh)2}2]2 (7), as well as a mono-nuclear zinc bis-diphenylphosphate complex, [(PMDETA)Zn{O2P(OPh)2}2] (6). 1H NMR DOSY has been used to calculate averaged molecular weights of the species. Studies are consistent with the disassembly of polymeric 3 into the bimetallic species [(Me-Py)2·Zn2{O2P(OPh)2}4], where the Me-Py ligand is in rapid exchange with free Me-Py in solution. Further 1H DOSY NMR studies of 4 and 5 reveal that dissolution of the complex results in a monomer dimer equilibrium, i.e., [(Bipy)Zn{O2P(OPh)2}2]2 ⇆ 2[(Bipy)Zn{O2P(OPh)2}2] and [(TMEDA)Zn{O2P(OPh)2}2]2 ⇆ 2[(TMEDA)Zn{O2P(OPh)2}2], respectively, in which the equilibria lie toward formation of the monomer. As part of our studies, variable temperature 1H DOSY experiments (223 to 313 K) were performed upon 5 in d8-tol, which allowed us to approximate the enthalpy [ΔH = -43.2 kJ mol-1 (±3.79)], entropy [ΔS = 109 J mol-1 K-1 (±13.9)], and approximate Gibbs free energy [ΔG = 75.6 kJ mol-1 (±5.62) at 293 K)] of monomer-dimer equilibria. While complex 6 is shown to maintain its monomeric solid-state structure, 1H DOSY experiments of 7 at 298 K reveal two separate normalized diffusion coefficients consistent with the presence of the bimetallic species [(TAC)2-xZn2{O2P(OPh)2}4], (x = 1 or 0) and free TAC ligand.

Potent and selective TYK2-JH1 inhibitors highly efficacious in rodent model of psoriasis.

TYK2 is a member of the JAK family of kinases and a key mediator of IL-12, IL-23, and type I interferon signaling. These cytokines have been implicated in the pathogenesis of multiple inflammatory and autoimmune diseases such as psoriasis, rheumatoid arthritis, lupus, and inflammatory bowel diseases. Supported by compelling data from human genetic association studies, TYK2 inhibition is an attractive therapeutic strategy for these diseases. Herein, we report the discovery of a series of highly selective catalytic site TYK2 inhibitors designed using FEP+ and structurally enabled design starting from a virtual screen hit. We highlight the structure-based optimization to identify a lead candidate 30, a potent cellular TYK2 inhibitor with excellent selectivity, pharmacokinetic properties, and in vivo efficacy in a mouse psoriasis model.

A perioperative multidisciplinary care bundle reduces surgical site infections in patients undergoing synchronous colorectal and liver resection.

BACKGROUND: Surgical site infections (SSIs) are a major cause of morbidity, mortality, and healthcare costs, and patients undergoing simultaneous colorectal/liver resections are at an especially high SSI risk. METHODS: Data were collected on all patients undergoing synchronous colorectal/liver resection from 2011 to 2016 (n = 424). The intervention, implemented in 2013, included 13 multidisciplinary perioperative components. The primary endpoints were superficial/deep and organ space SSIs. Secondary endpoints were hospital length of stay (LOS) and 30-day readmission rate. To control for changes in SSI rates independent of the intervention, interrupted time series analysis was conducted. RESULTS: Overall, superficial/deep, and organ space SSIs decreased by 60.5% (p < 0.001), 80.6% (p < 0.001), and 47.6% (p = 0.008), respectively. In the pre-intervention cohort (n = 231), there were 79 (34.2%), 31 (13.4%), and 48 (20.8%) total, superficial/deep, and organs space SSIs, respectively. In the post-intervention cohort (n = 193), there were 26 (13.5%), 5 (2.6%), and 21 (10.9%) total, superficial/deep, and organs space SSIs, respectively. Median LOS decreased from 9 to 8 days (p < 0.001). Readmission rates did not change (p = 0.6). Interrupted time series analysis found no significant trends in SSI rate within the pre-intervention (p = 0.35) and post-intervention (p = 0.55) periods. CONCLUSION: In combined colorectal/liver resection patients, implementation of a multidisciplinary care bundle was associated with a 61% reduction in SSIs, with the greatest impact on superficial/deep SSI, and modest reduction in LOS. The absence of trends within each time period indicated that the intervention was likely responsible for SSI reduction. Future efforts should target further reduction in organ space SSI.

Remote Nucleophilic Allylation by Allylrhodium Chain Walking.

Metal migration through a carbon chain is a versatile method for achieving remote functionalization. However, almost all known examples involve the overall net migration of alkylmetal species. Here, we report that allylrhodium species obtained from hydrorhodation of 1,3-dienes undergo chain walking toward esters, amides, or (hetero)arenes over distances of up to eight methylene units. The final, more highly conjugated allylrhodium species undergo nucleophilic allylation with aldehydes and with an imine to give Z-homoallylic alcohols and amines, respectively.

Chain Walking of Allylrhodium Species Towards Esters During Rhodium-Catalyzed Nucleophilic Allylations of Imines.

Allylrhodium species derived from δ-trifluoroboryl ß,γ-unsaturated esters undergo chain walking towards the ester moiety. The resulting allylrhodium species react with imines to give products containing two new stereocenters and a Z-alkene. By using a chiral diene ligand, products can be obtained with high enantioselectivities, where a pronounced matched/mismatched effect with the chirality of the allyltrifluoroborate is evident.

Human-animal relationships in zoo-housed orangutans (P. abelii) and gorillas (G. g. gorilla): the effects of familiarity.

I examined human-animal relationships (HARs) in zoo-housed orangutans (Pongo abelii) and gorillas (Gorilla gorilla gorilla) to see if they followed patterns similar to conspecific relationships in great apes and humans. Familiarity and social relationships guide humans' and great apes' behaviors with conspecifics. Inter-individual relationships, based on shared social history, and "generalized" relationships, based on a history of interactions with relevant classes of individuals, guide behavior with familiar and unfamiliar conspecifics, respectively. I examined whether both familiarity and social relationships similarly guides great apes' cross-species interactions with humans. I used repeated measures MANOVA to compare hourly rates and average durations of ape-initiated human-directed behaviors (HDBs) between familiar and unfamiliar humans and between great ape species. HDB patterns were consistent with familiarity-based HAR predictions, indicating more negative relationships with unfamiliar humans and more positive relationships with familiar humans. Findings for unfamiliar humans are consistent with negative effects of humans on apes' behavior reported in traditional visitor effect studies (VES). However, findings for familiar humans may be overlooked in VES due to pooling across levels of human familiarity or failure to consider humans other than primarily unfamiliar visitors. Additionally, species differences in apes' HDBs suggest that data pooling across species, common in many zoo studies, may mask important differences. These findings have important methodological implications for studies of human-animal interaction as well as for captive animal wellbeing.

Green Alternatives to Zinc Dialkyldithiophosphates: Vanadium Oxide-Based Additives.

A functionalized vanadyl(IV) acetylacetonate (acac) complex has been found to be a superior and highly effective antiwear agent, affording remarkable wear protection, compared to the current industry standard, zinc dialkyldithiophosphates (ZDDPs). Analysis of vanadium speciation and the depth profile of the active tribofilms by a combination of X-ray absorption near-edge structure (XANES), X-ray photoelectron spectroscopy (XPS), and near-edge X-ray absorption fine structure (NEXAFS) analyses indicated a mixed-valence oxide composite, comprising V(III), V(IV), and V(V) species. A marked difference in composition between the bulk and the surfaces of the tribofilms was found. The vanadyl(VI) acac precursor has the potential to reduce or even replace ZDDP, which would represent a paradigm shift in the antiwear agent design. A major benefit relative to ZDDPs is the absence of S and P moieties, eliminating the potential for forming noxious and environmentally harmful byproducts of these elements.

Sirtuin-mediated nuclear differentiation and programmed degradation in Tetrahymena.

BACKGROUND: The NAD(+)-dependent histone deacetylases, known as "sirtuins", participate in a variety of processes critical for single- and multi-cellular life. Recent studies have elucidated the importance of sirtuin activity in development, aging, and disease; yet, underlying mechanistic pathways are not well understood. Specific sirtuins influence chromatin structure and gene expression, but differences in their pathways as they relate to distinct chromatin functions are just beginning to emerge. To further define the range of global chromatin changes dependent on sirtuins, unique biological features of the ciliated protozoan Tetrahymena thermophila can be exploited. This system offers clear spatial and temporal separation of multiple whole genome restructuring events critical for the life cycle. RESULTS: Inhibition with nicotinamide revealed that sirtuin deacetylase activity in Tetrahymena cells promotes chromatin condensation during meiotic prophase, differentiation of heterochromatin from euchromatin during development, and chromatin condensation/degradation during programmed nuclear death. We identified a class I sirtuin, called Thd14, that resides in mitochondria and nucleoli during vegetative growth, and forms a large sub-nuclear aggregate in response to prolonged cell starvation that may be peripherally associated with nucleoli. During sexual conjugation and development Thd14 selectively concentrates in the parental nucleus prior to its apoptotic-like degradation. CONCLUSIONS: Sirtuin activity is important for several functionally distinct events requiring global chromatin condensation. Our findings suggest a novel role for sirtuins in promoting programmed pycnosis by acting on chromatin destined for degradation. The sirtuin Thd14, which displays physiological-dependent differential localization within the nucleus, is a candidate for a chromatin condensation enzyme that is coupled to nuclear degradation.

Comparing outcomes of robotic versus open mesorectal excision for rectal cancer.

BACKGROUND: The outcomes of robot-assisted mesorectal excision for rectal cancer, compared with open resection, have not been fully characterized. METHODS: A retrospective analysis of pathologic, short-term, and long-term outcomes in patients with rectal adenocarcinoma who underwent total or tumour-specific mesorectal excision at a high-volume cancer centre between 2008 and 2017 was conducted. Outcomes after robotic and open surgery were compared on an intention-to-treat basis. RESULTS: Out of 1048 resections performed, 1018 patients were reviewed, with 638 who underwent robotic surgery and 380 open surgery. Robotic surgery was converted to the open approach in 17 (2.7 per cent) patients. Patients who underwent robotic surgery were younger (median 54 (range 22-91) years versus median 58 (range 18-97) years; P < 0.001), had higher tumours (median 80 (range 0-150) mm from the anal verge versus median 70 (0-150) mm; P = 0.001), and were less likely to have received neoadjuvant therapy (64 per cent versus 73 per cent; P = 0.003). For patients who underwent a robotic total mesorectal excision, the operating time was longer (median 283.5 (range 117-712) min versus median 249 (range 70-661) min; P < 0.001). However, the rate of complications was lower (29 per cent versus 45 per cent; P < 0.001) and length of hospital stay was shorter (median 5 (range 1-32) days versus median 7 (range 0-137) days; P < 0.001). Median follow-up of survivors was 2.9 years. The proportion of patients with a positive circumferential resection margin did not differ between the groups, nor did the rate of local recurrence (robotic versus open: 3.7 per cent, 95 per cent c.i. 1.9 to 5.6 versus 2.8 per cent, 95 per cent c.i. 1.0 to 4.6; P = 0.400), systemic recurrence (robotic versus open: 11.7 per cent, 95 per cent c.i. 8.5 to 14.8 versus 13.0 per cent, 95 per cent c.i. 9.2 to 16.5; P = 0.300), or overall survival (robotic versus open: 97.8 per cent, 95 per cent c.i. 96.3 to 99.3 versus 93.5 per cent, 95 per cent c.i. 90.8 to 96.2; P = 0.050). The same results were documented in a subanalysis of 370 matched patients, including 185 who underwent robotic surgery and 185 open surgery, for the overall incidence of any postoperative complications, overall survival, disease-free survival, local recurrence, and systemic recurrence. CONCLUSION: In patients with rectal cancer who are candidates for curative resection, robotic mesorectal excision is associated with lower complication rates, shorter length of stay, and equivalent oncologic outcomes, compared with open mesorectal excision.

Enantioselective reduction of ketones and imines catalyzed by (CN-box)Re(V)-oxo complexes.

The development and application of chiral, non-racemic Re(V)-oxo complexes to the enantioselective reduction of prochiral ketones is described. In addition to the enantioselective reduction of prochiral ketones, we report the application of these complexes to 1) a tandem Meyer-Schuster rearrangement/reduction to access enantioenriched allylic alcohols and 2) the enantioselective reduction of imines.

Oxidative red blood cell damage associated with propofol and intravenous lipid emulsion therapy in a dog treated for 5-fluorouracil toxicosis.

OBJECTIVE: To describe the first documented case of oxidant-induced anemia in a dog associated with propofol and IV lipid emulsion (IVLE) treatment for 5-fluorouracil (5-FU) toxicosis. CASE SUMMARY: A 2-year-old male intact mixed breed dog was presented for evaluation after ingestion of 5% 5-FU cream. Refractory reactive seizures rapidly developed, and treatment with benzodiazepines, propofol, levetiracetam, and IVLE was initiated. The dog was euthanized due to development of marked oxidant-induced anemia. NEW INFORMATION PROVIDED: This report documents the first instance of oxidant-induced anemia in the dog, associated with propofol and IVLE infusion therapy prescribed for treatment of 5-FU toxicosis.

A class II histone deacetylase acts on newly synthesized histones in Tetrahymena.

Newly synthesized histones are acetylated prior to their deposition into nucleosomes. Following nucleosome formation and positioning, they are rapidly deacetylated, an event that coincides with further maturation of the chromatin fiber. The histone deacetylases (HDACs) used for histone deposition and de novo chromatin formation are poorly understood. In the ciliate Tetrahymena thermophila, transcription-related deacetylation in the macronucleus is physically separated from deposition-related deacetylation in the micronucleus. This feature was utilized to identify an HDAC named Thd2, a class II HDAC that acts on newly synthesized histones to remove deposition-related acetyl moieties. The THD2 transcript is alternatively spliced, and the major form contains a putative inositol polyphosphate kinase (IPK) domain similar to Ipk2, an enzyme that promotes chromatin remodeling by SWI/SNF remodeling complexes. Cells lacking Thd2, which retain deposition-related acetyl moieties on new histones, exhibit chromatin and cytological phenotypes indicative of a role for Thd2 in chromatin maturation, including the proteolytic processing of histone H3.

Refined annotation and assembly of the Tetrahymena thermophila genome sequence through EST analysis, comparative genomic hybridization, and targeted gap closure.

BACKGROUND: Tetrahymena thermophila, a widely studied model for cellular and molecular biology, is a binucleated single-celled organism with a germline micronucleus (MIC) and somatic macronucleus (MAC). The recent draft MAC genome assembly revealed low sequence repetitiveness, a result of the epigenetic removal of invasive DNA elements found only in the MIC genome. Such low repetitiveness makes complete closure of the MAC genome a feasible goal, which to achieve would require standard closure methods as well as removal of minor MIC contamination of the MAC genome assembly. Highly accurate preliminary annotation of Tetrahymena's coding potential was hindered by the lack of both comparative genomic sequence information from close relatives and significant amounts of cDNA evidence, thus limiting the value of the genomic information and also leaving unanswered certain questions, such as the frequency of alternative splicing. RESULTS: We addressed the problem of MIC contamination using comparative genomic hybridization with purified MIC and MAC DNA probes against a whole genome oligonucleotide microarray, allowing the identification of 763 genome scaffolds likely to contain MIC-limited DNA sequences. We also employed standard genome closure methods to essentially finish over 60% of the MAC genome. For the improvement of annotation, we have sequenced and analyzed over 60,000 verified EST reads from a variety of cellular growth and development conditions. Using this EST evidence, a combination of automated and manual reannotation efforts led to updates that affect 16% of the current protein-coding gene models. By comparing EST abundance, many genes showing apparent differential expression between these conditions were identified. Rare instances of alternative splicing and uses of the non-standard amino acid selenocysteine were also identified. CONCLUSION: We report here significant progress in genome closure and reannotation of Tetrahymena thermophila. Our experience to date suggests that complete closure of the MAC genome is attainable. Using the new EST evidence, automated and manual curation has resulted in substantial improvements to the over 24,000 gene models, which will be valuable to researchers studying this model organism as well as for comparative genomics purposes.

Transpalpebral ultrasonographic measurement of the optic nerve sheath diameter in healthy dogs.

OBJECTIVE: To develop a reference range for ultrasonographically measured optic nerve sheath diameter (ONSD-US) in dogs. We hypothesized that ONSD-US can be measured reliably and is associated with weight but not age, sex, or body condition score (BCS), and that the relationship between weight and ONSD-US in dogs is allometric due to canine size variations. DESIGN: Prospective, observational study. SETTING: University teaching hospital. ANIMALS: Seventy-eight healthy adult dogs. INTERVENTIONS: The ONSD was measured by a standardized transpalpebral approach. MEASUREMENTS AND MAIN RESULTS: Regression analysis showed the relationship between weight and ONSD was better fit with a linear model (R2 = 0.8510) than an allometric model (R2 = 0.7917). Multiple regression analysis showed ONSD is associated with weight (P < 0.0001), age (P = 0.0021), and BCS (P = 0.0007), but not with sex. Dominance analysis showed 94.6% of the variance explained by the model was due to weight. Intraclass correlation coefficient (ICC) analysis showed excellent interobserver (ICC = 0.9338-0.9608) and intraobserver (ICC = 0.9893) reliability. CONCLUSIONS: These results suggest that ONSD-US may be reliably measured in dogs using our described transpalpebral approach, and we have calculated prediction intervals based on body weight. Future studies are needed to determine if ONSD-US measurements are associated with intracranial hypertension as shown in human medicine.

The NEF4 complex regulates Rad4 levels and utilizes Snf2/Swi2-related ATPase activity for nucleotide excision repair.

Nucleotide excision repair factor 4 (NEF4) is required for repair of nontranscribed DNA in Saccharomyces cerevisiae. Rad7 and the Snf2/Swi2-related ATPase Rad16 are NEF4 subunits. We report previously unrecognized similarity between Rad7 and F-box proteins. Rad16 contains a RING domain embedded within its ATPase domain, and the presence of these motifs in NEF4 suggested that NEF4 functions as both an ATPase and an E3 ubiquitin ligase. Mutational analysis provides strong support for this model. The Rad16 ATPase is important for NEF4 function in vivo, and genetic analysis uncovered new interactions between NEF4 and Rad23, a repair factor that links repair to proteasome function. Elc1 is the yeast homologue of a mammalian E3 subunit, and it is a novel component of NEF4. Moreover, the E2s Ubc9 and Ubc13 were linked to the NEF4 repair pathway by genetic criteria. Mutations in NEF4 or Ubc13 result in elevated levels of the DNA damage recognition protein Rad4 and an increase in ubiquitylated species of Rad23. As Rad23 also controls Rad4 levels, these results suggest a complex system for globally regulating repair activity in vivo by controlling turnover of Rad4.

ZnO Nanoparticles Protect RNA from Degradation Better than DNA.

Gene therapy and RNA delivery require a nanoparticle (NP) to stabilize these nucleic acids when administered in vivo. The presence of degradative hydrolytic enzymes within these environments limits the nucleic acids' pharmacologic activity. This study compared the effects of nanoscale ZnO and MgO in the protection afforded to DNA and RNA from degradation by DNase, serum or tumor homogenate. For double-stranded plasmid DNA degradation by DNase, our results suggest that the presence of MgO NP can protect DNA from DNase digestion at an elevated temperature (65 °C), a biochemical activity not present in ZnO NP-containing samples at any temperature. In this case, intact DNA was remarkably present for MgO NP after ethidium bromide staining and agarose gel electrophoresis where these same stained DNA bands were notably absent for ZnO NP. Anticancer RNA, polyinosinic-polycytidylic acid (poly I:C) is now considered an anti-metastatic RNA targeting agent and as such there is great interest in its delivery by NP. For it to function, the NP must protect it from degradation in serum and the tumor environment. Surprisingly, ZnO NP protected the RNA from degradation in either serum-containing media or melanoma tumor homogenate after gel electrophoretic analysis, whereas the band was much more diminished in the presence of MgO. For both MgO and ZnO NP, buffer-dependent rescue from degradation occurred. These data suggest a fundamental difference in the ability of MgO and ZnO NP to stabilize nucleic acids with implications for DNA and RNA delivery and therapy.

Enzyme and Cancer Cell Selectivity of Nanoparticles: Inhibition of 3D Metastatic Phenotype and Experimental Melanoma by Zinc Oxide.

Biomedical applications for metal and metal oxide nanoparticles are rapidly increasing. Here their functional impact on two well-characterized model enzymes, Luciferase (Luc) or ß-galactosidase (ß-Gal) was quantitatively compared. Nickel oxide nanoparticle (NiO-NP) activated ß-Gal (>400% control) and boron carbide nanoparticle (B4C-NP) inhibited Luc(<10% control), whereas zinc oxide (ZnO-NP) and cobalt oxide (Co3O4-NP) activated ß-Gal to a lesser extent and magnesium oxide (MgO) moderately inhibited both enzymes. Melanoma specific killing was in the order; ZnO > B4C ≥ Cu > MgO > Co3O4 > Fe2O3 > NiO, ZnO-NP inhibiting B16F10 and A375 cells as well as ERK enzyme (>90%) and several other cancer-associated kinases (AKT, CREB, p70S6K). ZnO-NP or nanobelt (NB) serve as photoluminescence (PL) cell labels and inhibit 3-D multi-cellular tumor spheroid (MCTS) growth and were tested in a mouse melanoma model. These results demonstrate nanoparticle and enzyme specific biochemical activity and suggest their utility as new tools to explore the important model metastatic foci 3-D environment and their chemotherapeutic potential.

Transcriptional control of RAD51 expression in the ciliate Tetrahymena thermophila.

The expression of Rad51p, a DNA repair protein that mediates homologous recombination, is induced by DNA damage and during both meiosis and exconjugant development in the ciliate Tetrahymena thermophila. To completely investigate the transcriptional regulation of Tetrahymena RAD51 expression, reporter genes consisting of the RAD51 5' non-translated sequence (5' NTS) positioned upstream of either the firefly luciferase or green fluorescent protein coding sequences have been targeted for recombination at the macronuclear btu1-1 (K350M) locus of T. thermophila strain CU522. Expression from RAD51-luciferase reporter constructs has been directly quantified from transformant whole cell lysates. Luciferase is induced to maximum levels in transformants harboring the full-length RAD51-luciferase reporter gene following exposure to DNA damaging UV irradiation. A series of truncations, deletions, insertions, substitutions and inversions of the RAD51 5' NTS have led to the identification of three distinct transcriptional promoter elements. The first of these sequence elements is required for basal levels of transcription. The second modulates expression in the absence of DNA damage, whereas the third ensures increased RAD51 transcription in response to DNA damage and during meiosis. Tetrahymena RAD51 is tightly regulated through these transcriptional elements to produce the appropriate expression during conjugation, and in response to DNA damage.

Copper-catalyzed borylative coupling of vinylazaarenes and N-Boc imines.

Cu-catalyzed three-component couplings of vinylazaarenes, B2(pin)2, and N-Boc imines are described. Oxidation of the initially formed boronate gives azaarene-containing, Boc-protected amino alcohols with reasonable to good diastereoselectivities.