Abstract Traditional methods for the assembly of functionalised DNA structures, involving enzyme restriction and modification, present difficulties when working with small DNA fragments (<100bp), in part due to a lack of control over enzymatic action during the DNA modification process. This limits the design flexibility and range of accessible DNA structures. Here, we show that these limitations can be overcome by introducing chemical modifications into the DNA, which spatially restrict enzymatic activity. This approach, Sterically Controlled Nuclease Enhanced (SCoNE) DNA assembly, thereby circumvents the size limitations of conventional Gibson assembly (GA) and allows for the preparation of well-defined, functionalised DNA structures with multiple probes for specific analytes, such as IL-6, procalcitonin (PCT), and a biotin reporter group. Notably, using the same starting materials conventional GA under typical conditions fails. We demonstrate successful analyte capture based on standard and modified sandwich ELISA and also show how the inclusion of biotin probes provides additional functionality for product isolation.
Mammalian oocytes in ovarian follicles are arrested in meiosis at prophase I. This arrest is maintained until ovulation, upon which the oocyte exits from this arrest, progresses through meiosis I and to metaphase of meiosis II. The progression from prophase I to metaphase II, known as meiotic maturation, is mediated by signals that coordinate these transitions in the life of the oocyte. ENSA (α-endosulfine) and ARPP19 (cAMP-regulated phosphoprotein-19) have emerged as regulators of M-phase, with function in inhibition of protein phosphatase 2A (PP2A) activity. Inhibition of PP2A maintains the phosphorylated state of CDK1 substrates, thus allowing progression into and/or maintenance of an M-phase state. We show here ENSA in mouse oocytes plays a key role in the progression from prophase I arrest into M-phase of meiosis I. The majority of ENSA-deficient oocytes fail to exit from prophase I arrest. This function of ENSA in oocytes is dependent on PP2A, and specifically on the regulatory subunit PPP2R2D (also known as B55δ). Treatment of ENSA-deficient oocytes with Okadaic acid to inhibit PP2A rescues the defect in meiotic progression, with Okadaic acid-treated, ENSA-deficient oocytes being able to exit from prophase I arrest. Similarly, oocytes deficient in both ENSA and PPP2R2D are able to exit from prophase I arrest to an extent similar to wild-type oocytes. These data are evidence of a role for ENSA in regulating meiotic maturation in mammalian oocytes, and also have potential relevance to human oocyte biology, as mouse and human have genes encoding both Arpp19 and Ensa.
Abstract Background: Black and African Americans (AA) remain severely underrepresented in therapeutic oncology clinical trials (TOCTs) and have the highest cancer mortality rates compared to all other groups. Racially biased clinical trial offers, poor physician-patient communication, and social determinants of health largely contribute to these racial inequities. The UNC Lineberger CREATE Clinical Trial Patient Navigation (CTPN) program was established to advance racial equity in TOCT participation. The CTPN program entails clinical trial education, facilitating communication between patients and their medical/research team, identifying barriers to clinical trial participation and connecting patients to resources to address those barriers. Here we describe the health-related social needs and referrals made to address those needs. Methods: The CTPN program employed a targeted proactive approach to reach patients with a new cancer diagnosis who self-identified as Black/African American (AA) or were insured by Medicaid. The patient navigator used the electronic medical record (EMR) to review the oncologist's schedule to identify patients meeting the above criteria. Identified patients received a letter in the mail describing the CTPN program and were offered an in-person clinic visit and/or telephone call with the patient navigator. During these encounters, the patient navigator assessed clinical trial barriers including health-related social needs and made referrals to resources to help address these needs. The CTPN program was initially launched in the thoracic oncology clinic but later became available for direct referrals from all oncology groups. Results: In the first 18 months of the CTPN program, there were 292 patient encounters among183 unique patients who received navigation services. Most patients (83%) were identified through the EMR, 79% identify as Black or AA, 64% have Medicaid. Patients had a diagnosis of lung (62%), head and neck (18%), gynecological (9%), and breast (2%) cancers. Clinical trial related barriers and health-related social needs included lack of clinical trial knowledge (68%), housing (9%), transportation (26%), financial support (18%), and family/caregiver support (14%). CTPN program materials were provided to address clinical trial informational needs (78%), and referrals were made to assist with emotional (13%), logistical (20%), and financial (21%) needs. On average, 2 referrals were made per patient encounter. Conclusion: CTPN can engage Black/AA patients with cancer using a proactive EMR approach to identify patients and may help address health-related social needs to facilitate cancer care and potential clinical trial participation. Future work will evaluate the impact of CTPN on enrollment of Black/AAs in therapeutic cancer clinical trials. Citation Format: Ashley Rankin Collins, Hayley N. Morris, Lauren N. Matthews, Omar N. Buenaventura Gomez, Marjory Charlot. Health related social needs of people with cancer underrepresented in clinical trials: Early experience of the Cancer Research Equity and Advocacy through Engagement Initiative (CREATE) clinical trial patient navigation program [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B136.
It can be challenging for clinicians to predict which patients with respiratory failure secondary to coronavirus disease 2019 (COVID-19) will fail on high-flow nasal cannula (HFNC) oxygen and require escalation of therapy. This study set out to evaluate the association between the respiratory rate-oxygenation index (ROX) and HFNC failure in such patients and to assess whether ROX trajectory correlates with treatment failure.
This report presents a case of Lemierre syndrome caused by Fusobacterium necrophorum in a healthy young adult who presented atypically with shortness of breath and jaundice but no clinical or diagnostic evidence of thrombophlebitis. Due to this unusual presentation with jaundice, diagnosis was challenging and delayed. However, the patient was successfully initiated on a prolonged course of intravenous antibiotics; he required a period in the intensive care unit and was discharged without significant complications. This report aims to raise awareness of the diagnosis and treatment of this rare condition and to highlight both common and unusual presentations of the syndrome.
Abstract Background: Participation of racially diverse populations in research is necessary to advance cancer care. However, representation of Black individuals in biospecimen cancer research remains low and requires being asked to engage in research. We sought to understand the experiences, beliefs, and knowledge about biospecimen research among Black patients with lung cancer. Methods: Semi-structured interviews with a purposive sample of 15 Black patients diagnosed with lung cancer were conducted between January and August 2022 at a large academic center in North Carolina. Interviews were digitally recorded and transcribed and analyzed using thematic analysis. Results: Themes related to who should initiate discussions about biospecimen donation, what should be considered before donation, and communication strategies to increase participation of Black patients with cancer in biospecimen research emerged from the interviews. Most participants indicated that discussions about biospecimen donation should be initiated by trusted and knowledgeable members of the medical team and most expressed trusting their providers. Some also expressed the importance of including family members in discussions about medical and research decisions. Some participants felt it was important to consider if donating specimens would cause pain or would require additional procedures. Recommended communication strategies to facilitate participation included use of simple and easily understood language in addition to messaging related to how biospecimen donation would benefit others. Participants also felt cultural humility, respect, and empathy during research recruitment would help enhance enrollment of Black participants in biospecimen research. Of note, all participants reported never being asked to participate in biospecimen research and felt that underrepresentation of Black participants may be due to not being asked. Conclusion: Black participants in this study have not been asked to participate in biospecimen research but are willing to be engaged in conversations about research from their medical team. Simply being asked, trusting their medical provider, cultural humility, and framing the message on how the research will benefit others are some of the recommended strategies to enhance research participation among Black patients. Future research should incorporate these strategies into an intervention to assess the impact on recruiting Black individuals in biomedical research. Sponsored by the Lung Cancer Research Foundation Research Grant on Disparities in Lung Cancer Citation Format: Jeenn A. Barreiro-Rosa, Oluwatumilara Akeke, Annabella Opoku, Alison Hilton, Jessica Carda-Auten, Randall Teal, Aaron Carpenter, Hayley N. Morris, Lauren Matthews, Ashley Rankin Collins, Marjory Charlot. “Simply ask and explain”: perspectives from Black patients with lung cancer on strategies to address racial disparities in biospecimen research participation. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5534.
Colloidal gels are out of equilibrium soft solids composed of attractive Brownian particles that form a space-spanning network at low volume fractions. The elastic properties of these systems result from the network microstructure, which is very sensitive to shear history. Here, we take advantage of such sensitivity to tune the viscoelastic properties of a colloidal gel made of carbon black nanoparticles. Starting from a fluidized state under an applied shear rate $\dot γ_0$, we use an abrupt flow cessation to trigger a liquid-to-solid transition. We observe that the resulting gel is all the more elastic when the shear rate $\dot γ_0$ is low and that the viscoelastic spectra can be mapped on a master curve. Moreover, coupling rheometry to small angle X-ray scattering allows us to show that the gel microstructure is different from gels solely formed by thermal agitation where only two length scales are observed: the dimension of the colloidal and the dimension the fractal aggregates. Competition between shear and thermal energy leads to gels with three characteristic length scales. Such gels structure in a percolated network of fractal clusters that interpenetrate each other. Experiments on gels prepared with various shear histories reveal that cluster interpenetration increases with decreasing values of the shear rate $\dot γ_0$ applied before flow cessation. These observations strongly suggest that cluster interpenetration drives the gel elasticity, which we confirm using a structural model. Our results, which are in stark contrast with previous literature, where gel elasticity was either linked to cluster connectivity or to bending modes, highlight a novel local parameter controlling the macroscopic viscoelastic properties of colloidal gels.
