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1.
Mol Biol Evol ; 40(8)2023 08 03.
Article in English | MEDLINE | ID: mdl-37494292

ABSTRACT

Though the phylogenetic signal of loci on sex chromosomes can differ from those on autosomes, chromosomal-level genome assemblies for nonvertebrates are still relatively scarce and conservation of chromosomal gene content across deep phylogenetic scales has therefore remained largely unexplored. We here assemble a uniquely large and diverse set of samples (17 anchored hybrid enrichment, 24 RNA-seq, and 70 whole-genome sequencing samples of variable depth) for the medically important assassin bugs (Reduvioidea). We assess the performance of genes based on multiple features (e.g., nucleotide vs. amino acid, nuclear vs. mitochondrial, and autosomal vs. X chromosomal) and employ different methods (concatenation and coalescence analyses) to reconstruct the unresolved phylogeny of this diverse (∼7,000 spp.) and old (>180 Ma) group. Our results show that genes on the X chromosome are more likely to have discordant phylogenies than those on autosomes. We find that the X chromosome conflict is driven by high gene substitution rates that impact the accuracy of phylogenetic inference. However, gene tree clustering showed strong conflict even after discounting variable third codon positions. Alternative topologies were not particularly enriched for sex chromosome loci, but spread across the genome. We conclude that binning genes to autosomal or sex chromosomes may result in a more accurate picture of the complex evolutionary history of a clade.


Subject(s)
Reduviidae , Animals , Phylogeny , Biological Evolution , Genome , X Chromosome/genetics
2.
J Am Chem Soc ; 143(50): 21127-21142, 2021 12 22.
Article in English | MEDLINE | ID: mdl-34860516

ABSTRACT

The rising prevalence of multidrug-resistant bacteria is an urgent health crisis that can only be countered through renewed investment in the discovery and development of antibiotics. There is no panacea for the antibacterial resistance crisis; instead, a multifaceted approach is called for. In this Perspective we make the case that, in the face of evolving clinical needs and enabling technologies, numerous validated antibacterial targets and associated lead molecules deserve a second look. At the same time, many worthy targets lack good leads despite harboring druggable active sites. Creative and inspired techniques buoy discovery efforts; while soil screening efforts frequently lead to antibiotic rediscovery, researchers have found success searching for new antibiotic leads by studying underexplored ecological niches or by leveraging the abundance of available data from genome mining efforts. The judicious use of "polypharmacology" (i.e., the ability of a drug to alter the activities of multiple targets) can also provide new opportunities, as can the continued search for inhibitors of resistance enzymes with the capacity to breathe new life into old antibiotics. We conclude by highlighting available pharmacoeconomic models for antibacterial discovery and development while making the case for new ones.


Subject(s)
Anti-Bacterial Agents/chemistry , Drug Discovery , Alkyl and Aryl Transferases/chemistry , Alkyl and Aryl Transferases/metabolism , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Drug Resistance, Multiple, Bacterial/drug effects , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/metabolism , Gram-Positive Bacteria/drug effects , Gram-Positive Bacteria/metabolism , beta-Lactamase Inhibitors/chemistry , beta-Lactamase Inhibitors/metabolism , beta-Lactamases/chemistry , beta-Lactamases/metabolism
3.
Mol Phylogenet Evol ; 130: 297-303, 2019 01.
Article in English | MEDLINE | ID: mdl-30359745

ABSTRACT

Target enrichment of conserved genomic regions facilitates collecting sequences of many orthologous loci from non-model organisms to address phylogenetic, phylogeographic, population genetic, and molecular evolution questions. Bait sets for sequence capture can simultaneously target thousands of loci, which opens new avenues of research on speciose groups. Current phylogenetic hypotheses on the >103,000 species of Hemiptera have failed to unambiguously resolve major nodes, suggesting that alternative datasets and more thorough taxon sampling may be required to resolve relationships. We use a recently designed ultraconserved element (UCE) bait set for Hemiptera, with a focus on the suborder Heteroptera, or the true bugs, to test previously proposed relationships. We present newly generated UCE data for 36 samples representing three suborders, all seven heteropteran infraorders, 23 families, and 34 genera of Hemiptera and one thysanopteran outgroup. To improve taxon sampling, we also mined additional UCE loci in silico from published hemipteran genomic and transcriptomic data. We obtained 2271 UCE loci for newly sequenced hemipteran taxa, ranging from 265 to 1696 (average 904) per sample. These were similar in number to the data mined from transcriptomes and genomes, but with fewer loci overall. The amount of missing data correlates with greater phylogenetic divergence from taxa used to design the baits. This bait set hybridizes to a wide range of hemipteran taxa and specimens of varying quality, including dried specimens as old as 1973. Our estimated phylogeny yielded topologies consistent with other studies for most nodes and was strongly-supported. We also demonstrate that UCE loci are almost exclusively from the transcribed portion of the genome, thus data can be successfully integrated with existing genomic and transcriptomic resources for more comprehensive phylogenetic sampling, an important feature in the era of phylogenomics. UCE approaches can be used by other researchers for additional studies on hemipteran evolution and other research that requires well resolved phylogenies.


Subject(s)
Conserved Sequence/genetics , Genomics/methods , Hemiptera/classification , Hemiptera/genetics , Phylogeny , Animals , Genetic Loci , Likelihood Functions , Sequence Analysis, DNA , Transcriptome/genetics
4.
Proc Natl Acad Sci U S A ; 113(37): E5472-80, 2016 Sep 13.
Article in English | MEDLINE | ID: mdl-27573827

ABSTRACT

More than 2 million people in the United States have myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). We performed targeted, broad-spectrum metabolomics to gain insights into the biology of CFS. We studied a total of 84 subjects using these methods. Forty-five subjects (n = 22 men and 23 women) met diagnostic criteria for ME/CFS by Institute of Medicine, Canadian, and Fukuda criteria. Thirty-nine subjects (n = 18 men and 21 women) were age- and sex-matched normal controls. Males with CFS were 53 (±2.8) y old (mean ± SEM; range, 21-67 y). Females were 52 (±2.5) y old (range, 20-67 y). The Karnofsky performance scores were 62 (±3.2) for males and 54 (±3.3) for females. We targeted 612 metabolites in plasma from 63 biochemical pathways by hydrophilic interaction liquid chromatography, electrospray ionization, and tandem mass spectrometry in a single-injection method. Patients with CFS showed abnormalities in 20 metabolic pathways. Eighty percent of the diagnostic metabolites were decreased, consistent with a hypometabolic syndrome. Pathway abnormalities included sphingolipid, phospholipid, purine, cholesterol, microbiome, pyrroline-5-carboxylate, riboflavin, branch chain amino acid, peroxisomal, and mitochondrial metabolism. Area under the receiver operator characteristic curve analysis showed diagnostic accuracies of 94% [95% confidence interval (CI), 84-100%] in males using eight metabolites and 96% (95% CI, 86-100%) in females using 13 metabolites. Our data show that despite the heterogeneity of factors leading to CFS, the cellular metabolic response in patients was homogeneous, statistically robust, and chemically similar to the evolutionarily conserved persistence response to environmental stress known as dauer.

5.
J Dairy Sci ; 102(10): 9236-9240, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31400904

ABSTRACT

Transrectal palpation of the reproductive tract is the most common method for pregnancy determination in cattle and is considered a veterinary skill that new veterinary medicine (DVM) graduates should perform proficiently. However, using privately owned cattle to train students can be difficult because producers may believe that transrectal palpation by inexperienced students increases the risk of pregnancy wastage compared with examination by an experienced clinician. We used a randomized field trial of 1,216 healthy Holstein and Jersey cattle in 2 commercial dairy herds to estimate the effect of veterinary student transrectal palpation on early pregnancy loss. All cattle were determined to be pregnant using transrectal ultrasonography at approximately 37 d after artificial insemination. Cattle were then allocated into 2 groups based upon their ear tag number (study group = 598; control group = 618). Cattle in the study group were immediately palpated after ultrasonography by a fourth-year veterinary student, whereas control cattle were not subject to any additional pregnancy assessment. For analysis, the student palpators were divided into 2 groups: students who had previously had formal palpation training via an elective bovine palpation class (n = 30) and students who had not had palpation training (n = 134). All cattle were reevaluated using transrectal ultrasonography approximately 70 d after artificial insemination. A total of 53 (4.36%) animals lost their pregnancy between the first and second pregnancy assessments. Of the animals that lost their pregnancy, 26 (4.35%) were study group cows and 27 (4.37%) were control cows. Of the 26 cows documented to have had pregnancy loss within the study group, 20 out of 378 (5.3%) had been palpated by students who had not taken the palpation elective and 6 out of 220 (2.7%) had been palpated by students who had completed the elective. We found no difference in pregnancy loss between student-palpated and clinician-ultrasounded cattle, supporting the safety of using privately owned animals for student bovine palpation and pregnancy diagnosis training without affecting early pregnancy loss.


Subject(s)
Abortion, Veterinary , Education, Veterinary , Palpation , Pregnancy Tests , Animals , Cattle , Female , Humans , Pregnancy , Abortion, Veterinary/etiology , Palpation/adverse effects , Pregnancy Tests/veterinary , Students , Ultrasonography, Prenatal/veterinary
6.
Appl Environ Microbiol ; 82(24): 7123-7133, 2016 12 15.
Article in English | MEDLINE | ID: mdl-27694238

ABSTRACT

The insect order Hemiptera, one of the best-studied insect lineages with respect to bacterial symbioses, still contains major branches that lack comprehensive characterization of associated bacterial symbionts. The Pyrrhocoroidea (Largidae [220 species] and Pyrrhocoridae [∼300 species]) is a clade of the hemipteran infraorder Pentatomomorpha. Studies on bacterial symbionts of this group have focused on members of Pyrrhocoridae, but recent examination of species of two genera of Largidae demonstrated divergent symbiotic complexes in these putative sister families. We surveyed the associated bacterial diversity of this group using paired-end Illumina sequencing and targeted Sanger sequencing of bacterial 16S rRNA amplicons of 30 pyrrhocoroid taxa, including 17 species of Largidae, in order to determine bacterial associates and the similarity of associated microbial communities among species. We also used molecular data (4,800 bp in 5 loci, for 57 ingroup and 12 outgroup taxa) to infer a phylogeny of the host superfamily, in order to trace the evolution of symbiotic complexes among Pentatomomorpha species. We undertook multiple lines of investigation (i.e., experimental rearing, fluorescence in situ hybridization microscopy, and phylogenetic and coevolutionary analyses) to elucidate potential transmission routes for largid symbionts. We found a prevalent and specific association of Largidae with Burkholderia strains of the plant-associated beneficial and environmental clade, housed in midgut tubules. As in other distantly related Heteroptera, symbiotic bacteria seem to be acquired from the environment every generation. We review the current understanding of symbiotic complexes within Pentatomomorpha and discuss means to further investigate the evolution and function of these symbioses. IMPORTANCE: Obligate symbioses with bacteria are common in insects, particularly Hemiptera, in which various forms of symbiosis occur. However, knowledge regarding symbionts remains incomplete for major hemipteran lineages. Thus, an accurate understanding of how these partnerships evolved and changed over millions of years is not yet achievable. We contribute to our understanding of the evolution of symbiotic complexes in Hemiptera by characterizing bacterial associates of Pyrrhocoroidea, focusing on the family Largidae. Members of Largidae are associated with specific symbiotic Burkholderia strains from a different clade than Burkholderia symbionts in other Burkholderia-associated Hemiptera. Evidence suggests that species of Largidae reacquire specific symbiotic bacteria from the environment every generation, which is a rare strategy for insects, with potentially volatile evolutionary ramifications, but one that must have persisted in Largidae and related lineages since their origin in the Cretaceous Period.


Subject(s)
Bacteria/genetics , Bacteria/isolation & purification , Heteroptera/microbiology , Phylogeny , Symbiosis , Animals , Bacteria/classification , Bacterial Physiological Phenomena , Biological Evolution , Heteroptera/physiology
7.
Mol Phylogenet Evol ; 94(Pt A): 65-73, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26314664

ABSTRACT

Stenophagy, specialization of a clade on a narrow range of taxa, has not been well studied in speciose clades of predators, principally due to the difficulty of obtaining adequate natural history data. The pantropical Salyavatinae (Hemiptera: Reduviidae; 17 genera, 107 species) contains members with enigmatic morphology and specialized behavior for feeding on termites. All Salyavatinae are suspected specialist termite predators; however, existing observations are limited to seven species. Prior analyses indicate that Salyavatinae may be paraphyletic with respect to another subfamily, Sphaeridopinae, also hypothesized to feed on termites. A molecular phylogeny of these putative termite assassins is here constructed using seven loci from 28 species in nine genera and is used in a dating analysis to shed light on the timing of Neotropical colonization by this primarily Old World clade. DNA extracted from gut contents of 50 individuals was assayed using PCR with prey-specific primers.Molecular assays, along with recent photographs and observations, provide substantial evidence that this clade feeds specifically upon termites, documenting 28 new individual associations. Our phylogeny supports a sister group relationship of the Neotropical genus Salyavata with Sphaeridopinae. Termite association data combined with our phylogeny provide evidence of previously unknown prey conservatism among clades of one of the most diverse groups of specialist termite predators.


Subject(s)
Isoptera , Phylogeny , Predatory Behavior , Reduviidae/classification , Reduviidae/physiology , Africa , Animals , Crowdsourcing , Diet/veterinary , Food Preferences , Polymerase Chain Reaction , Reduviidae/genetics , Sequence Analysis, DNA
8.
J Shoulder Elbow Surg ; 25(4): 614-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26652697

ABSTRACT

BACKGROUND: Tranexamic acid (TXA) significantly decreases blood loss and transfusion rates after total hip and total knee arthroplasty. The purpose of this study was to determine the effects of intravenous TXA on blood loss and patient outcomes after total shoulder arthroplasty (TSA). METHODS: TXA was used in 106 consecutive patients undergoing primary anatomic and reverse TSA with a dose of 20 mg/kg intravenously (TXA group) and compared with the previous consecutive 88 patients without TXA (non-TXA group). All patients had a blood sample drawn for a hemoglobin and hematocrit determination the morning after surgery. Analysis of variance and χ(2) techniques were used to analyze study hypotheses. RESULTS: Statistically significant differences in both hemoglobin loss (TXA group Δ = 2.13 vs. non-TXA group Δ = 2.63; P = .01) and hematocrit loss (TXA group Δ = 6.4 vs. non-TXA group Δ = 8.14; P < .01) were seen in the TXA group compared with the non-TXA group. In patients receiving TXA, there were statistically significant decreases in the time spent in the recovery room (mean, TXA group 69 minutes vs. non-TXA group 87 minutes; P < .02) and total length of hospitalization (mean, TXA group 1.18 days vs. non-TXA group 1.4 days; P = .01). Two patients in the TXA group received a blood transfusion, whereas 6 patients in the non-TXA group did. CONCLUSIONS: TXA 20 mg/kg intravenously given just before primary anatomic and reverse TSA results in statistically significant reductions in blood loss. Patients spent 21% less time in the recovery room and had a 16% shorter hospitalization, resulting in financial savings for the hospital.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Arthroplasty, Replacement , Blood Loss, Surgical/prevention & control , Postoperative Hemorrhage/prevention & control , Shoulder Joint/surgery , Tranexamic Acid/therapeutic use , Antifibrinolytic Agents/administration & dosage , Blood Transfusion , Female , Humans , Infusions, Intravenous , Length of Stay , Male , Postoperative Hemorrhage/etiology , Retrospective Studies , Tranexamic Acid/administration & dosage
11.
Structure ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38889720

ABSTRACT

Disulfide-rich peptides such as defensins play diverse roles in immunity and ion channel modulation, as well as constituting the bioactive components of many animal venoms. We investigated the structure and bioactivity of U-RDTX-Pp19, a peptide previously discovered in venom of the assassin bug Pristhesancus plagipennis. Recombinant Pp19 (rPp19) was found to possess insecticidal activity when injected into Drosophila melanogaster. A bioinformatic search revealed that domains homologous to Pp19 are produced by assassin bugs and diverse other arthropods. rPp19 co-eluted with native Pp19 isolated from P. plagipennis, which we found is more abundant in hemolymph than venom. We solved the three-dimensional structure of rPp19 using 2D 1H NMR spectroscopy, finding that it adopts a disulfide-stabilized structure highly similar to known trans-defensins, with the same cystine connectivity as human α-defensin (I-VI, II-IV, and III-V). The structure of Pp19 is unique among reported structures of arthropod peptides.

12.
J Hered ; 104(2): 202-16, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23325865

ABSTRACT

Landscape alterations have dramatic impacts on the distribution of genetic variation within and among populations and understanding these effects can guide contemporary and future conservation strategies. We initiated a landscape-scale genetic study of the coastal tailed frog (Ascaphus truei) on commercial timberlands within the southern range of the species in Mendocino County (CA, USA). In total, 294 individuals from 13 populations were analyzed at 9 microsatellite loci. None of the sampled populations departed from mutation-drift equilibrium, indicating recent population bottlenecks were not detected in contemporary samples. Fine-scale analysis indicated sampled populations were structured at the watershed level (mean F (ST) = 0.077 and mean G'(ST) = 0.425). Landscape analyses suggested wet and moist areas may serve as significant corridors for gene flow within watersheds in this region (r (2) = 0.32-0.54 for moisture-related features). Results indicate populations of frogs may have persisted at this scale through intense periods of timber harvest, making southern range edge populations of coastal tailed frogs resilient to past land use practices.


Subject(s)
Anura/genetics , Sequoia , Trees , Alleles , Animals , California , Evolution, Molecular , Gene-Environment Interaction , Genetic Variation , Genetics, Population , Genotype , Microsatellite Repeats
13.
R Soc Open Sci ; 10(6): 230307, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37388308

ABSTRACT

Target capture is widely used in phylogenomic, ecological and functional genomic studies. Bait sets that allow capture from a diversity of species can be advantageous, but high-sequence divergence from baits can limit yields. Currently, only four experimental comparisons of a critical target capture parameter, hybridization temperature, have been published. These have been in vertebrates, where bait divergences are typically low, and none include invertebrates where bait-target divergences may be higher. Most invertebrate capture studies use a fixed, high hybridization temperature to maximize the proportion of on-target data, but many report low locus recovery. Using leaf-footed bugs (Hemiptera: Coreoidea), we investigate the effect of hybridization temperature on capture success of ultraconserved elements targeted by (i) baits developed from divergent hemipteran genomes and (ii) baits developed from less divergent coreoid transcriptomes. Lower temperatures generally resulted in more contigs and improved recovery of targets despite a lower proportion of on-target reads, lower read depth and more putative paralogues. Hybridization temperatures had less of an effect when using transcriptome-derived baits, which is probably due to lower bait-target divergences and greater bait tiling density. Thus, accommodating low hybridization temperatures during target capture can provide a cost-effective, widely applicable solution to improve invertebrate locus recovery.

14.
Sci Rep ; 12(1): 20559, 2022 11 29.
Article in English | MEDLINE | ID: mdl-36446872

ABSTRACT

Host-microbe interactions are intimately linked to eukaryotic evolution, particularly in sap-sucking insects that often rely on obligate microbial symbionts for nutrient provisioning. Cicadas (Cicadidae: Auchenorrhyncha) specialize on xylem fluid and derive many essential amino acids and vitamins from intracellular bacteria or fungi (Hodgkinia, Sulcia, and Ophiocordyceps) that are propagated via transmission from mothers to offspring. Despite the beneficial role of these non-gut symbionts in nutrient provisioning, the role of beneficial microbiota within the gut remains unclear. Here, we investigate the relative abundance and impact of host phylogeny and ecology on gut microbial diversity in cicadas using 16S ribosomal RNA gene amplicon sequencing data from 197 wild-collected cicadas and new mitochondrial genomes across 38 New Zealand cicada species, including natural hybrids between one pair of two species. We find low abundance and a lack of phylogenetic structure and hybrid effects but a significant role of elevation in explaining variation in gut microbiota.


Subject(s)
Alphaproteobacteria , Gastrointestinal Microbiome , Hemiptera , Animals , Hemiptera/genetics , Phylogeny , Gastrointestinal Microbiome/genetics , New Zealand
15.
PeerJ ; 9: e11019, 2021.
Article in English | MEDLINE | ID: mdl-33850647

ABSTRACT

Despite many bioinformatic solutions for analyzing sequencing data, few options exist for targeted sequence retrieval from whole genomic sequencing (WGS) data with the ultimate goal of generating a phylogeny. Available tools especially struggle at deep phylogenetic levels and necessitate amino-acid space searches, which may increase rates of false positive results. Many tools are also difficult to install and may lack adequate user resources. Here, we describe a program that uses freely available similarity search tools to find homologs in assembled WGS data with unparalleled freedom to modify parameters. We evaluate its performance compared to other commonly used bioinformatics tools on two divergent insect species (>200 My) for which annotated genomes exist, and on one large set each of highly conserved and more variable loci. Our software is capable of retrieving orthologs from well-curated or unannotated, low or high depth shotgun, and target capture assemblies as well or better than other software as assessed by recovering the most genes with maximal coverage and with a low rate of false positives throughout all datasets. When assessing this combination of criteria, ALiBaSeq is frequently the best evaluated tool for gathering the most comprehensive and accurate phylogenetic alignments on all types of data tested. The software (implemented in Python), tutorials, and manual are freely available at https://github.com/AlexKnyshov/alibaseq.

16.
J Atten Disord ; 24(10): 1443-1456, 2020 08.
Article in English | MEDLINE | ID: mdl-26823382

ABSTRACT

Objective: This study tested a novel feed-forward modeling (FFM) system as a nonpharmacological intervention for the treatment of ADHD children and the training of cognitive skills that improve academic performance. Method: This study implemented a randomized, controlled, parallel design comparing this FFM with a nonpharmacological community care intervention. Improvements were measured on parent- and clinician-rated scales of ADHD symptomatology and on academic performance tests completed by the participant. Participants were followed for 3 months after training. Results: Participants in the FFM training group showed significant improvements in ADHD symptomatology and academic performance, while the control group did not. Improvements from FFM were sustained 3 months later. Conclusion: The FFM appeared to be an effective intervention for the treatment of ADHD and improving academic performance. This FFM training intervention shows promise as a first-line treatment for ADHD while improving academic performance.


Subject(s)
Academic Performance , Attention Deficit Disorder with Hyperactivity , Attention , Attention Deficit Disorder with Hyperactivity/therapy , Child , Humans , Parents , Treatment Outcome
17.
ACS Med Chem Lett ; 11(2): 162-165, 2020 Feb 13.
Article in English | MEDLINE | ID: mdl-32071683

ABSTRACT

Aztreonam, first discovered in 1980, is an FDA approved, intravenous, monocyclic beta-lactam antibiotic. Aztreonam is active against Gram-negative bacteria and is still used today. The oral bioavailability of aztreonam in humans is less than 1%. Herein we describe the design and synthesis of potential oral prodrugs of aztreonam.

18.
J Am Chem Soc ; 131(31): 10830-1, 2009 Aug 12.
Article in English | MEDLINE | ID: mdl-19621928

ABSTRACT

High-resolution two-dimensional (2D) (1)H-(15)N heteronuclear correlation (HETCOR) spectroscopy has been used to characterize the structure and dynamics of (15)N-backbone labeled antimicrobial piscidin 1 (p1) oriented in "native-like" hydrated lipid bilayers. Piscidin belongs to a family of amphipatic cationic antimicrobial peptides, which are membrane-active and have broad spectrum antimicrobial activity on bacteria. When the (1)H chemical shifts are encoded by the (1)H-(15)N dipolar couplings, 2D dipolar-encoded HETCOR (i.e., de-HETCOR) solid-state NMR spectra yield high resolution (1)H and (15)N chemical shifts as well as (1)H-(15)N heteronuclear dipolar couplings. Several advantages of HETCOR and de-HETCOR techniques that emerge from our investigations could facilitate the atomic-level investigations of structure-function relationships in membrane-active peptides and membrane-bound species. First, the de-HETCOR NMR spectrum of a ten-site (15)N-labeled sample of p1 aligned in hydrated lipid bilayers can resolve resonances that are overlapped in the standard HETCOR spectrum. Second, the resolution in de-HETCOR spectra of p1 improves significantly at higher magnetic field due to an enhanced alignment that improves spectrum definition uniformly. Third, the HETCOR spectrum of (15)N-K(14) p1 oriented in hydrated lipid bilayers displays not only the expected crosscorrelation between the chemical shifts of bonded amide(1)H and (15)N spins but also a cross peak between the (1)H chemical shift from bulk water and the (15)N chemical shift from the labeled amide nitrogen. This information provides new insights into the intermolecular interactions of an amphipathic antimicrobial peptide optimized to partition at the water-bilayer interface and may have implications at the biological level.


Subject(s)
Antimicrobial Cationic Peptides/chemistry , Lipid Bilayers/chemistry , Nuclear Magnetic Resonance, Biomolecular/methods , Water/chemistry , Nitrogen Isotopes
19.
Bioorg Med Chem Lett ; 19(15): 4437-40, 2009 Aug 01.
Article in English | MEDLINE | ID: mdl-19482472

ABSTRACT

The synthesis and biochemical evaluation of novel cyanothiazolidine inhibitors of dipeptidyl peptidase 4 (DPP4) is described. Their main structural feature is a constrained bicyclic core that prevents the intramolecular formation of inactive cyclic species. The inhibitors show good to moderate biochemical potency against DPP4 and display distinct selectivity profiles towards DPP7, DPP8 and DPP9 depending on their substitution.


Subject(s)
Azabicyclo Compounds/chemical synthesis , Dipeptidyl-Peptidase IV Inhibitors/chemical synthesis , Enzyme Inhibitors/chemical synthesis , Nitriles/chemical synthesis , Thiazolidines/chemical synthesis , Azabicyclo Compounds/pharmacology , Catalysis , Diabetes Mellitus/drug therapy , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Drug Design , Enzyme Inhibitors/pharmacology , Humans , Inhibitory Concentration 50 , Models, Chemical , Molecular Structure , Nitriles/pharmacology , Protein Structure, Tertiary , Pyrrolidines/chemistry , Structure-Activity Relationship , Thiazoles/chemistry , Thiazolidines/pharmacology , Time Factors
20.
J Orthop ; 16(3): 195-200, 2019.
Article in English | MEDLINE | ID: mdl-30906122

ABSTRACT

PURPOSE: To investigate racial disparities in shoulder arthroplasty (SA), accounting for demographic factors such as sex and age. METHODS: Data for SAs (2011-2014) was queried from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample. Population-adjusted SA utilization rates, racial and sex differences by age, length of stay, insurer, and comorbidities were calculated. RESULTS: Caucasians aged 45-64 are 54% more likely than African-Americans and 74% than Hispanics to receive surgery. For patients aged 65-84, the disparity is wider for African-Americans and narrower for Hispanics. CONCLUSIONS: Policymakers and physicians should focus on further national efforts to alleviate healthcare disparities.

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