Covariance mapping spectroscopy of ultrafast laser induced biomolecular dissociation

This thesis reports the development of and first results from femtosecond laser-induced ionisation/dissociation (fs-LID) two-dimensional partial covariance mass spectrometry (2D-PC- MS) of biomolecules. Collision induced dissociation (CID) 2D-PC-MS is first extended to oligonucleotides. 2D- PC-MS fragment–fragment correlations are shown to give more sequence-specific information for oligonucleotides than the individual fragment analysis of 1D MS/MS. This is particularly relevant in the important case of modified oligonucleotides, where common sequencing methods can struggle to discover the nature and location of chemical modifications. The experimental development of fs-LID 2D-PC-MS runs in parallel with predictive simulations of the laser–ion cloud overlap in our experimental system, which inform the experimental parameters required for success. The discovery that contaminant free measurements are possible in negative ion mode, combined with oligonucleotides being more amenable to negative ion mode MS, the relevant experience from oligonucleotide CID 2D-PC-MS and the fact that, to the best of our knowledge, fs-LID activated MS of oligonucleotides was unprecedented, lead to a focus on fs-LID 2D-PC-MS of oligonucleotide anions. Novel 2D-PC-MS molecular diagrams are developed to give insights into the fragmentation patterns of phosphorylated peptides and oligonucleotides. These diagrams visually represent the relative probabilities of a molecule taking the fragmentation pathways found to be strongest when correlated fragment pairs are ranked by their 2D-PC-MS significance score. Comparing 2D-PC-MS molecular diagrams for CID and fs-LID activation elucidated mechanistic differences in the fragmentation behaviour between the statistical bond-breaking of CID and the ultrafast fragmentation triggered by fs-LID. A comparison of the fs-LID fragmentation pathways around different riboses finds that the nature of the ribose greatly influences the local fragmentation behaviour. In a wider context, investigating laser–biomolecule interaction mechanisms could contribute to the understanding of light–biomolecule interactions such as sunlight interacting with living cells.Open Acces

Somatic insulin signaling regulates a germline starvation response in Drosophila egg chambers

AbstractEgg chambers from starved Drosophila females contain large aggregates of processing (P) bodies and cortically enriched microtubules. As this response to starvation is rapidly reversed upon re-feeding females or culturing egg chambers with exogenous bovine insulin, we examined the role of endogenous insulin signaling in mediating the starvation response. We found that systemic Drosophila insulin-like peptides (dILPs) activate the insulin pathway in follicle cells, which then regulate both microtubule and P body organization in the underlying germline cells. This organization is modulated by the motor proteins Dynein and Kinesin. Dynein activity is required for microtubule and P body organization during starvation, while Kinesin activity is required during nutrient-rich conditions. Blocking the ability of egg chambers to form P body aggregates in response to starvation correlated with reduced progeny survival. These data suggest a potential mechanism to maximize fecundity even during periods of poor nutrient availability, by mounting a protective response in immature egg chambers

Assessing Peer Mentor Skill Development in Participating in a Novel Medical Student Mentoring Initiative

BackgroundLearning communities in medical schools create a bridge for senior students to engage with junior peers, providing advice and support as mentors. In this process, mentors are likely to gain skills in communication, empathy, and leadership - well received traits for residency. Methods We aim to elucidate an objective measure of mentor growth and development during the mentorship program. We will evaluate opinions on the program\u27s ability to foster professional attributes including leadership, communication, and empathy; determining features that benefit them while assessing for paradigms of improvement. We will survey 24 M2-students through self-rated queries on a Likert scale. This survey will be administered to mentors at two time-points: half-way and at the end of the program. Results From the mid-point survey, 22 out of 24 total mentors responded. Most mentors feel satisfied with the support that they receive from the program, specifically with the time commitment while not feeling overwhelmed with their duties. Finally, mentors find an importance in building mentee confidence and helping mentees to meet their goals, but most do not feel skilled at this. Conclusion The survey results provide valuable insight regarding mentors’ personal and professional development. We identified mentors’ needs for increased support. In a follow-up study, we will assess how the program can develop educational interventions to aid mentors in developing abilities to communicate, lead, and mentor. We additionally hope to establish a rigorous quality-assessment tool to be used year-over-year in assessing program development while also defining avenues to improve mentors’ professional development

Learning Community Student-Resident Physician Mentorship

Wayne State University School of Medicine (WSUSOM) in 2018 formed Learning Communities (LCs), that facilitate student engagement, comradery, and mentoring. These programs include medical student-premed, near-peer, and faculty/attending mentorships. There has been an identified gap in mentorship between near-peer and faculty/attending mentorship, and that is near-peer mentors at WSUSOM have yet to complete the residency process to guide other students through it. Moreover, faculty/attending mentors are more removed from residency and may not have relevant advice for students. As resident physicians are recent graduates, they are more likely to provide relevant insight about residency applications, academic challenges, and efficiency than attendings. We aim to assess the extent of the gap between faculty/attending and peer mentorships. MS4 at WSUSOM (N=33) self-reported their: confidence in transitioning to residency; the gaps they believe such mentorship will fill; and whether they, themselves, would participate in an MS-resident fellowship program. Results indicated that MS4s feel somewhat confident in their abilities to transition to residency. They believe that a resident-MS mentorship would help in the interview and application process, as well as, the residency program choosing process. Furthermore, if given the opportunity, all the students would consider joining the program. We hope to implement a student-resident mentorship program, to reassure students on their journey to residency

Dose-Dependent Effects of Multiple Acute Cocaine Injections on Maternal Behavior and Aggression in Sprague-Dawley Rats

Rat dams, which had no prior drug treatment, were either nontreated controls or were injected subcutaneously 4 times during a 10-day period with a single dose of 30, 15 or 7.5 mg/kg of cocaine hydrochloride HCl, or normal saline. Injections were given immediately postpartum following delivery of their final pup (PPD 1), and again on postpartum day 3 (PPD 3), postpartum day 6 (PPD 6) and postpartum day 10 (PPD 10). Dams were observed 30 min following injections for maternal behavior (MB) towards 8 surrogate male pups on PPD 1 and PPD 3 and for aggression towards a male or female intruder in the presence of their litter on PPD 6 and PPD 10. Compared to saline and untreated controls, cocaine-treated dams exhibited more disruptions in MB on both PPD 1 and PPD 3 and were less aggressive towards an intruder, regardless of intruder sex, on PPD 6 and PPD 10. In most cases MB was altered in a dose-dependent manner with the higher doses of cocaine resulting in a greater disruption of behavior

Genome-wide analysis identifies 12 loci influencing human reproductive behavior.

The genetic architecture of human reproductive behavior-age at first birth (AFB) and number of children ever born (NEB)-has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

Enhancing Digital Information Access in Public Libraries

To explore the impact of public digital library resources on urban residents, to elucidate the current usage patterns of public digital library resources/services and levels of satisfaction with the resources/content in urban digital libraries and make recommendations as to steps that would improve service to this population