[West J Emerg Med. 2012;13(1):121–122.]

First-principles quantum calculations for anharmonic vibrational spectroscopy of three protected dipeptides are carried out and compared with experimental data. Using hybrid HF/MP2 potentials, the Vibrational Self-Consistent Field with Second-Order Perturbation Correction (VSCF-PT2) algorithm is used to compute the spectra without any ad hoc scaling or fitting. All of the vibrational modes (135 for the largest system) are treated quantum mechanically and anharmonically using full pair-wise coupling potentials to represent the interaction between different modes. In the hybrid potential scheme the MP2 method is used for the harmonic part of the potential and a modified HF method is used for the anharmonic part. The overall agreement between computed spectra and experiment is very good and reveals different signatures for different conformers. This study shows that first-principles spectroscopic calculations of good accuracy are possible for dipeptides hence it opens possibilities for determination of dipeptide conformer structures by comparison of spectroscopic calculations with experiment.

Birds use their legs and wings when transitioning from aerial to ground locomotion during landing. To improve our understanding of the effects of footpad dermatitis (FPD) and keel bone fracture (KBF) upon landing biomechanics in laying hens, we measured ground-reaction forces generated by hens (n = 37) as they landed on force plates (Bertec Corporation, Columbus, OH) from a 30 cm drop or 170 cm jump in a single-blinded placebo-controlled trial using a cross-over design where birds received an anti-inflammatory (meloxicam, 5 mg/kg body mass) or placebo treatment beforehand. We used generalized linear mixed models to test for effects of health status, treatment and their interaction on landing velocity (m/s), maximum resultant force (N), and impulse (force integrated with respect to time [N s]). Birds with FPD and KBF tended to show divergent alterations to their landing biomechanics when landing from a 30 cm drop, with a higher landing velocity and maximum force in KBF compared to FPD birds, potentially indicative of efforts to either reduce the use of their wings or impacts on inflamed footpads. In contrast, at 170 cm jumps fewer differences between birds of different health statuses were observed likely due to laying hens being poor flyers already at their maximum power output. Our results indicate that orthopedic injuries, apart from being welfare issues on their own, may have subtle influences on bird mobility through altered landing biomechanics that should be considered.

In 2022, the Food and Drug Administration approved a second mitral transcatheter edge-to-edge repair device for the treatment of primary mitral regurgitation (PASCAL Precision Transcatheter Valve Repair System, Edwards Lifesciences, Irvine, CA). The PASCAL Precision system consists of a guide sheath, implant system, and accessories. The implant system consists of a steerable catheter, an implant catheter, and the implant (PASCAL or PASCAL Ace). The guide sheath and steerable catheter move and flex independently from each other and are not keyed, allowing for freedom of rotation in three dimensions. This manuscript provides an overview of the PASCAL Precision system and describes the basic and advanced steering maneuvers to facilitate effective and safe mitral transcatheter edge-to-edge repair.

Introduction  Race, ethnicity, and socioeconomic status (SES) are complex, interconnected social determinants of health outcomes. This study uses multivariable analysis on a combination of large national datasets to examine the effects of these factors on 5-year disease-specific survival (DSS) and conditional DSS (CDSS) for nasopharyngeal carcinoma (NPC). Methods  A retrospective study of adults with NPC between 2000 and 2017 from the Surveillance, Epidemiology, End Results (SEER) registry was performed, using the National Cancer Institute Yost Index, a census tract-level composite score of SES to categorize patients. Kaplan-Meier analysis and Coxs regression for DSS and CDSS were stratified by SES. Logistic regression was conducted to identify risk factors for advanced cancer stage at time of diagnosis and receiving multimodal therapy. Results  Our analysis included 5,632 patients. DSS was significantly associated with race and SES ( p  < 0.01). Asian/Pacific Islander patients exhibited increased survival when controlling for other variables (hazard ratio [HR] = 0.73, p  < 0.01). Although Black patients were more likely to be diagnosed with advanced disease (Black odds ratio [OR] = 1.47, p  < 0.01), Black patients were also less likely to receive multimodal therapy; however, this relationship lost statistical significance once SES was incorporated into the multivariable analysis. DSS was decreased among the lowest (first) and middle (second) tertiles of SES (first HR = 1.34, p  < 0.01; second HR = 1.20, p  < 0.01) compared with the highest (third). Conclusion  Our results indicate that race, ethnicity, and SES significantly affect survival, stage at diagnosis, and treatment of NPC. An interplay of tumor biology and inequalities in access to care likely drives these disparities.

Background

Downy mildews are the most speciose group of oomycetes and affect crops of great economic importance. So far, there is only a single deeply-sequenced downy mildew genome available, from Hyaloperonospora arabidopsidis. Further genomic resources for downy mildews are required to study their evolution, including pathogenicity effector proteins, such as RxLR effectors. Plasmopara halstedii is a devastating pathogen of sunflower and a potential pathosystem model to study downy mildews, as several Avr-genes and R-genes have been predicted and unlike Arabidopsis downy mildew, large quantities of almost contamination-free material can be obtained easily.

Results

Here a high-quality draft genome of Plasmopara halstedii is reported and analysed with respect to various aspects, including genome organisation, secondary metabolism, effector proteins and comparative genomics with other sequenced oomycetes. Interestingly, the present analyses revealed further variation of the RxLR motif, suggesting an important role of the conservation of the dEER-motif. Orthology analyses revealed the conservation of 28 RxLR-like core effectors among Phytophthora species. Only six putative RxLR-like effectors were shared by the two sequenced downy mildews, highlighting the fast and largely independent evolution of two of the three major downy mildew lineages. This is seemingly supported by phylogenomic results, in which downy mildews did not appear to be monophyletic.

Conclusions

The genome resource will be useful for developing markers for monitoring the pathogen population and might provide the basis for new approaches to fight Phytophthora and downy mildew pathogens by targeting core pathogenicity effectors.

The oomycete vegetable pathogen Phytophthora capsici has shown remarkable adaptation to fungicides and new hosts. Like other members of this destructive genus, P. capsici has an explosive epidemiology, rapidly producing massive numbers of asexual spores on infected hosts. In addition, P. capsici can remain dormant for years as sexually recombined oospores, making it difficult to produce crops at infested sites, and allowing outcrossing populations to maintain significant genetic variation. Genome sequencing, development of a high-density genetic map, and integrative genomic or genetic characterization of P. capsici field isolates and intercross progeny revealed significant mitotic loss of heterozygosity (LOH) in diverse isolates. LOH was detected in clonally propagated field isolates and sexual progeny, cumulatively affecting >30percent of the genome. LOH altered genotypes for more than 11,000 single-nucleotide variant sites and showed a strong association with changes in mating type and pathogenicity. Overall, it appears that LOH may provide a rapid mechanism for fixing alleles and may be an important component of adaptability for P. capsici.