ObjectiveThe purpose of this project was to use an in vivo method to discover riboswitches that are activated by new ligands. We employed phage-assisted continuous evolution (PACE) to evolve new riboswitches in vivo. We started with one translational riboswitch and one transcriptional riboswitch, both of which were activated by theophylline. We used xanthine as the new target ligand during positive selection followed by negative selection using theophylline. The goal was to generate very large M13 phage populations that contained unknown mutations, some of which would result in new aptamer specificity. We discovered side products of three new theophylline translational riboswitches with different levels of protein production.ResultsWe used next generation sequencing to identify M13 phage that carried riboswitch mutations. We cloned and characterized the most abundant riboswitch mutants and discovered three variants that produce different levels of translational output while retaining their theophylline specificity. Although we were unable to demonstrate evolution of new riboswitch ligand specificity using PACE, we recommend careful design of recombinant M13 phage to avoid evolution of “cheaters” that short circuit the intended selection pressure.Electronic supplementary materialThe online version of this article (10.1186/s13104-018-3965-6) contains supplementary material, which is available to authorized users.
e18152 Background: Oncology patient navigation programs have been successfully implemented at hospitals throughout the U.S., enhancing the quality of canceer care. In low resource settings, the barriers to receiving cancer care are increased and a patient navigator in this setting has the potential to significantly impact outcomes. However, research on efficacy is limited. Methods: At Bugando Medical Centre (BMC) in Mwanza, Tanzania, semi-structured qualitative interviews of 15 key stakeholders in the oncology department and 15 families of patient with pediatric cancer diagnoses were completed to identify health system delivery and patient related barriers to timeliness of diagnosis, treatment initiation, and treatment completion. Based on identified barriers, a pilot patient navigation program was established to assist patients and their families with care coordination throughout the diagnosis and treatment process. A retrospective analysis of hospital records was conducted of all pediatric oncology patients seen at BMC from 2010-2016, separated by presentation date before or after establishment of navigation program. Collected data includes demographics, diagnosis, time from presentation to oncology evaluation and diagnosis, and treatment completion. Results: Identified patient related barriers included patient diagnosis and treatment knowledge, and complexity of care. Health system delivery barriers included limited provider capacity, and poor care coordination between the oncology providers, other health care services and patient families. A total of 238 patient files were reviewed, with 169 pre- and 69 post- program initiation. Patient groups did not differ by age or gender (p = 0.329 and 0.744), or diagnosis distribution. The average time to oncology evaluation decreased from 49.7 to 16.6 days (p = 0.015), and time to diagnosis decreased from 49.1 to 23.6 days (p = 0.07). Treatment abandonment decreased from 50% to 38% (p < 0.001). Conclusions: In pediatric oncology, early diagnosis is critical to the initiation of chemotherapy and improving outcomes. These data suggest that a patient navigation program is feasible in a LMIC and can impact both health system inefficiency and treatment abandonment, with the potential to improve pediatric cancer outcomes.
Background Injection drug use among people admitted to rural jails has significant implications for both infectious disease transmission and incarceration patterns. This study examines the relationship between injection drug use, jail readmission, and detention duration to inform interventions designed specifically for this understudied correctional setting. Methods The Comprehensive Addiction and Psychological Evaluation-5 (CAAPE-5) was administered to a random sample of adults admitted to two county detention centers in Western North Carolina. Data regarding readmission and the length of detention were obtained for the 12-month study period. Results Participants included 420 adults, aged 18–66 years. Nearly three-quarters (70.9%) met criteria for at least one substance use disorder (SUD) and almost half (45.7%) met criteria for multiple SUDs. Approximately half (45.2%) reported injecting drugs, with the majority (71.6%) reporting injecting methamphetamine, followed by 51.1% who injected opioids. People who injected drugs were 1.83 times more likely (95% CI = 1.17–2.87) than those who did not inject to be admitted on multiple occasions and also spent a significantly longer amount of time detained (IRR = 1.34, 95% CI = 1.02–1.77) during the 12-month follow-up period. Limitations The study was limited to jails in two counties and injection-related factors may vary from other facilities. Conclusions The association between drug injection and longer detention periods presents an opportunity to engage people with infectious disease screening and substance use services in jails. Connection to stable primary and behavioral health care after release is a high priority in enhancing community health.
Borate transporters are membrane transport proteins that regulate intracellular borate levels. In plants, borate is a micronutrient essential for growth but is toxic in excess, while in yeast, borate is unnecessary for growth and borate export confers tolerance. Borate transporters share structural homology with human bicarbonate transporters in the SLC4 family despite low sequence identity and differences in transported solutes. Here, we characterize the S. cerevisiae borate transporter Bor1p and examine whether key biochemical features of SLC4 transporters extend to borate transporters. We show that borate transporters and SLC4 transporters share multiple properties, including lipid-promoted dimerization, sensitivity to stilbene disulfonate-derived inhibitors, and a requirement for an acidic residue at the solute binding site. We also identify several amino acids critical for Bor1p function and show that disease-causing mutations in human SLC4A1 will eliminate in vivo function when their homologous mutations are introduced in Bor1p. Our data help elucidate mechanistic features of Bor1p and reveal significant functional properties shared between borate transporters and SLC4 transporters.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.