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1.
HCA Healthc J Med ; 5(2): 139-143, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984218

RESUMEN

Introduction: The pathophysiology of keloid formation is poorly understood, and current treatments, including intralesional corticosteroids, cryotherapy, and surgery, are often associated with high resistance to treatment and recurrence. The multifactorial pathogenesis of keloid formation suggests that aberrant inflammatory cytokine signaling associated with keratinocyte dysregulation may contribute to keloid-associated pruritus. Case Presentation: In this paper, we report 2 cases of keloid-associated pruritus that were successfully treated with topical crisaborole 2% ointment, a phosphodiesterase 4 (PDE4) inhibitor. Both patients had previously undergone multiple unsuccessful treatments before being treated with crisaborole 2% ointment. In both cases, the patients experienced complete relief of pruritus with no significant change in keloid size, thickness, or appearance. Conclusion: We propose that PDE4 inhibitors, such as crisaborole, may be an effective therapy for keloid- associated pruritus.

2.
HCA Healthc J Med ; 5(2): 97-102, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984223

RESUMEN

Description Seborrheic dermatitis is a common dermatologic disease affecting patients of all ages, ethnicities, and skin pigmentations. The rash often affects the scalp, ears, and central face. The underlying skin pigmentation of the individual may affect how this disease presents. We present several cases of seborrheic dermatitis in individuals of varying ages, genders, and skin pigmentations.

3.
HCA Healthc J Med ; 5(2): 103-111, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984232

RESUMEN

Description Atopic dermatitis is a chronic inflammatory skin disorder classically affecting flexural areas of the body. It is present in children and adults, including those with darker skin pigmentation. Chronic lesions are hyperpigmented plaques that are dry, cracked, and/or scaly often with lichenification. Differential diagnoses include psoriasis, seborrheic dermatitis, ichthyosis, and pityriasis rosea. This article will showcase clinical images with varying presentations of chronic atopic dermatitis in a range of age groups and skin colors according to the Fitzpatrick scale.

4.
HCA Healthc J Med ; 5(2): 113-123, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984231

RESUMEN

Description Porokeratosis was first described in 1893. It is a relatively rare disorder with over 9 subtypes. Lesions are clinically characterized as well-demarcated, erythematous papules (raised, <1 cm) or plaques (raised, >1 cm), with an atrophic center, and raised scaly border. Porokeratosis is an important diagnosis to identify because it may undergo malignant transformation and mimics many commonly encountered diagnoses. These commonly mimicked diagnoses include squamous cell carcinoma, tinea corporis, nummular dermatitis, and psoriasis vulgaris, to name a few. The clinical images in this review focus on identifying porokeratosis along the full spectrum of skin tones.

5.
J Vasc Surg Cases Innov Tech ; 10(4): 101516, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39040133

RESUMEN

Testicular seminoma is rarely associated with occlusive venous thrombosis. Several investigators describe percutaneous guidewire recanalization for iliofemoral vein thrombosis; however, this technique is ill-documented for occlusion of the inferior vena cava, and even less information is available on managing pervasive iliocaval obstruction. Furthermore, there is limited data on percutaneous mechanical thrombectomy for malignancy-induced venous thrombosis. We present a case of symptomatic chronic occlusion of the inferior vena cava and iliac veins following remission for metastatic seminoma, with percutaneous intervention necessitating a unique combination of sharp wire recanalization, mechanical thrombectomy, and stenting to restore iliocaval patency.

6.
bioRxiv ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38915666

RESUMEN

Viral invasion of the host cell causes some of the most dramatic changes in biology. Human cytomegalovirus (HCMV) extensively remodels host cells, altering nuclear shape and generating a cytoplasmic viral-induced assembly compartment (vIAC). How these striking morphology changes take place in the context of host gene regulation is still emerging. Here, we discovered that histone variant macroH2A1 is essential for producing infectious progeny. Because virion maturation and cellular remodeling are closely linked processes, we investigated structural changes in the host cell upon HCMV infection. We discovered that macroH2A1 is necessary for HCMV-induced reorganization of the host nucleus, cytoskeleton, and endoplasmic reticulum. Furthermore, using RNA-seq we found that while all viral genes were highly expressed in the absence of macroH2A1, many HCMV-induced host genes were not. Remarkably, hundreds of these HCMV-induced macroH2A1-dependent host genes are associated with neuronal synapse formation and vesicle trafficking. Knock-down of these HCMV-induced neuronal genes during infection resulted in malformed vIACs and smaller plaques, establishing their importance to HCMV infection. Together, our findings demonstrate that HCMV manipulates host gene expression by hijacking a dormant neuronal secretory pathway for efficient virion maturation.

7.
Ann Vasc Surg ; 106: 360-368, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38821476

RESUMEN

BACKGROUND: Antiplatelets and statins therapies are associated with improved cardiovascular outcomes following major vascular intervention. Many vascular surgery institutions are reporting improved prescribing rates for aspirin (ASA), P2Y12 antagonists, and statins. Nevertheless, there remains limited publication describing rates and patient-perceived barriers for postoperative adherence. The purpose of this study is to investigate patient nonadherence to antiplatelet and statin therapies following major vascular intervention. METHODS: A retrospective review of patients who underwent major vascular intervention at a single academic center was performed. The prescribing rates of ASA, P2Y12 antagonists, and statins were reviewed. Postoperative adherence, defined as consistent intake as prescribed, was evaluated at 1, 3, 6, 9, and 12 months using electronic documentation of both follow-up clinic appointments and phone call assessments, then corroborated with pharmacy fulfilment records. Patient-reported barriers to medication adherence were also examined. RESULTS: A total of 101 subjects underwent major vascular intervention between January 2020 and July 2020, 98% of whom were discharged on at least 1 antiplatelet or statin agent. Approximately 90% of patients were discharged with ASA, 32% with a P2Y12 antagonist, and 96% with a statin. All patients who maintained adherence up to 6 months continued to report adherence at 9 and 12 months. Consistent adherence at 12 months was documented in 76% of patients on ASA, 81% on P2Y12 antagonism therapy, and 73% on statins. New adverse drug reactions represented the most common barrier to achieving adherence (37% [n = 20]). Preoperative therapy with ASA, P2Y12 antagonists, and statins were all independently predictive of postoperative adherence to the same regimen (P ≤ 0.001). The female gender was also associated with higher rates of adherence to postoperative P2Y12 antagonism therapy (P ≤ 0.05). CONCLUSIONS: The current prescribing rates for antiplatelet and statin agents are promising, but postoperative nonadherence remains a multifaceted issue.

8.
Rare Tumors ; 16: 20363613241255669, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756435

RESUMEN

Laryngeal schwannoma is a rare benign nerve sheath tumor that is slow growing. The diagnosis is made from a combination of clinical, radiological, and histopathological findings, and the main method of treatment is resection. We report a case of a 69-year-old presenting with a neck mass causing stridor, dysphagia, and orthopnea. CT of the neck showed an enhancing mass measuring 6.3 cm and extending superior to the larynx. Emergent tracheostomy and mass resection were performed, and histopathology and immunohistochemical findings were obtained from the specimen supporting schwannoma. In conclusion, while rare, schwannoma should always be considered as a differential diagnosis for a laryngeal mass. More studies are needed to assess the size and prognosis of the tumor.

9.
Annu Rev Virol ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684115

RESUMEN

Viruses are exemplary molecular biologists and have been integral to scientific discovery for generations. It is therefore no surprise that nuclear replicating viruses have evolved to systematically take over host cell function through astoundingly specific nuclear and chromatin hijacking. In this review, we focus on nuclear replicating DNA viruses-herpesviruses and adenoviruses-as key examples of viral invasion in the nucleus. We concentrate on critical features of nuclear architecture, such as chromatin and the nucleolus, to illustrate the complexity of the virus-host battle for resources in the nucleus. We conclude with a discussion of the technological advances that have enabled the discoveries we describe and upcoming steps in this burgeoning field.

10.
HCA Healthc J Med ; 5(1): 19-25, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560397

RESUMEN

Description Acne vulgaris is a common inflammatory skin condition of the pilosebaceous unit in adolescents and young adults and is primarily characterized by the presence of open and closed comedones. In patients of various skin pigmentations, skin-colored comedones may be difficult to appreciate and lead to incorrect or delayed diagnosis of acne. To aid in the identification of acne vulgaris in patients of various skin pigmentations, we present comedonal acne in different skin types and commonly encountered differential diagnoses. With its significant volume and burden of disease, acne vulgaris should be correctly identified in various skin pigmentations by primary care clinicians for the initiation of appropriate management.

11.
bioRxiv ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38645103

RESUMEN

Collision of a replication fork with a DNA nick is thought to generate a one-ended break, fostering genomic instability. Collision of the opposing converging fork with the nick could, in principle, form a second DNA end, enabling conservative repair by homologous recombination (HR). To study mechanisms of nickase-induced HR, we developed the Flp recombinase "step arrest" nickase in mammalian cells. Flp-nickase-induced HR entails two-ended, BRCA2/RAD51-dependent short tract gene conversion (STGC), BRCA2/RAD51-independent long tract gene conversion, and discoordinated two-ended invasions. HR induced by a replication-independent break and by the Flp-nickase differ in their dependence on BRCA1 . To determine the origin of the second DNA end during Flp-nickase-induced STGC, we blocked the opposing fork using a site-specific Tus/ Ter replication fork barrier. Flp-nickase-induced STGC remained robust and two-ended. Thus, collision of a single replication fork with a Flp-nick can trigger two-ended HR, possibly reflecting replicative bypass of lagging strand nicks. This response may limit genomic instability during replication of a nicked DNA template.

12.
Nucl Med Commun ; 45(6): 474-480, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38465449

RESUMEN

OBJECTIVE: To compare the incidence and natural course of reactive axillary lymph nodes (RAL) between mRNA and attenuated whole-virus vaccines using Deauville criteria. METHODS: In this multi-institutional PET-CT study comprising multiple vaccine types (Pfizer-BioNTech/Comirnaty, Moderna/Spikevax, Sinovac/CoronaVac and Janssen vaccines), we evaluated the incidence and natural course of RAL in a large cohort of oncological patients utilizing a standardized Deauville scaling system (n=522; 293 Female, Deauville 3-5 positive for RAL). Univariate and multivariate analyses were conducted to evaluate the predictive value of clinical parameters (absolute neutrophil count [ANC], platelets, age, sex, tumor type, and vaccine-to-PET interval) for PET positivity. RESULTS: Pfizer-BioNTech/Comirnaty and Moderna vaccines revealed similar RAL incidences for the first 20 days after the second dose of vaccine administration (44% for the first 10 days for both groups, 26% vs. 20% for 10-20 days, respectively for Moderna and Pfizer). However, Moderna recipients revealed significantly higher incidences of RAL after 20 days compared to Pfizer-BioNTech/Comirnaty, with nodal reactivity spanning up to the 9th week post-vaccination (15% vs. 4%, respectively P  < 0.001). No RAL was observed in patients who received either a single dose of J&J vaccine or two doses of CroronaVac. Younger patients showed increased likelihood of RAL, otherwise, clinical/demographic parameters were not predictive of RAL ( P  = 0.014 for age, P  > 0.05 for additional clinical/demographic parameters). CONCLUSION: RAL based on strict PET criteria was observed with mRNA but not with attenuated whole-virus vaccines, in line with higher immunogenicity and stronger protection offered by mRNA vaccines.


Asunto(s)
Axila , Vacunas contra la COVID-19 , Ganglios Linfáticos , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Vacunación , Vacunas Atenuadas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , COVID-19/prevención & control , Vacunas de ARNm , Estudios Retrospectivos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Anciano de 80 o más Años , Vacunas Sintéticas
13.
J Vasc Surg Venous Lymphat Disord ; : 101875, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38513797

RESUMEN

OBJECTIVE: Patients undergoing intervention for acute iliofemoral deep vein thrombosis (IFDVT) with May-Thurner syndrome (MTS) typically require inpatient (IP) hospitalization for initial treatment with anticoagulation and management with pharmacomechanical thrombectomy. Direct oral anticoagulants and percutaneous mechanical thrombectomy (PMT) devices offer the opportunity for outpatient (OP) management. We describe our approach with these patients. METHODS: Patients receiving intervention for acute IFDVT from January 2020 through October 2022 were retrospectively reviewed. Patients undergoing unilateral thrombectomy, venous angioplasty, and stenting for IFDVT with MTS comprised the study population and were divided into two groups: (1) patients admitted to the hospital and treated as IPs and (2) patients who underwent therapy as OPs. The two groups were compared regarding demographics, risk factors, procedural success, complications, and follow-up. RESULTS: A total of 92 patients were treated for IFDVT with thrombectomy, angioplasty, and stenting of whom 58 comprised the IP group and 34 the OP group. All 92 patients underwent PMT using the Inari ClotTriever (Inari Medical), intravascular ultrasound, angioplasty, and stenting with 100% technical success. Three patients in the IP group required adjuvant thrombolysis. There was no difference in primary patency of the treated IFDVT segment at 12 months between the two groups (IP, 73.5%; OP, 86.7%; P = .21, log-rank test). CONCLUSIONS: Patients with acute IFDVT and MTS deemed appropriate for thrombectomy and iliac revascularization can be managed with initiation of ambulatory direct oral anticoagulant therapy and subsequent return for ambulatory PMT, angioplasty, and stenting. This approach avoids the expense of IP care and allows for effective use of resources at a time when staffing and supply chain shortages have led to inefficiencies in the provision of IP care for nonemergent conditions.

14.
Acad Radiol ; 31(5): 1799-1804, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38103973

RESUMEN

Large language models (LLMs) such as ChatGPT and Bard have emerged as powerful tools in medicine, showcasing strong results in tasks such as radiology report translations and research paper drafting. While their implementation in clinical practice holds promise, their response accuracy remains variable. This study aimed to evaluate the accuracy of ChatGPT and Bard in clinical decision-making based on the American College of Radiology Appropriateness Criteria for various cancers. Both LLMs were evaluated in terms of their responses to open-ended (OE) and select-all-that-apply (SATA) prompts. Furthermore, the study incorporated prompt engineering (PE) techniques to enhance the accuracy of LLM outputs. The results revealed similar performances between ChatGPT and Bard on OE prompts, with ChatGPT exhibiting marginally higher accuracy in SATA scenarios. The introduction of PE also marginally improved LLM outputs in OE prompts but did not enhance SATA responses. The results highlight the potential of LLMs in aiding clinical decision-making processes, especially when guided by optimally engineered prompts. Future studies in diverse clinical situations are imperative to better understand the impact of LLMs in radiology.


Asunto(s)
Algoritmos , Detección Precoz del Cáncer , Humanos , Detección Precoz del Cáncer/métodos , Toma de Decisiones Clínicas/métodos , Neoplasias/diagnóstico por imagen , Sistemas de Información Radiológica
15.
Rare Tumors ; 15: 20363613231212383, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37909028

RESUMEN

Introduction: Thyroid cancer is the most common endocrine tumor in humans. Follicular adenoma/carcinoma is the second most common subtype. Multiple histological patterns have been identified. Follicular adenoma with bizarre nuclei is one of the patterns associated with p53 mutation and has an unclear clinical prognosis. Case report: A 74-year-old female presented with incidental findings of elevated TSH levels and normal thyroid markers. Ultrasound was performed and revealed multiple bilateral thyroid nodules measuring up to 1.9 cm. Fine needle aspiration was performed, and cytology showed one Bethesda category 5 nodule. Total thyroidectomy with neck dissection was performed, and the pathology showed follicular adenoma with bizarre nuclei. Based on the results of immunohistochemistry, the neoplastic cells exhibited staining for wild-type p53 and low levels of the proliferation index Ki-67. Conclusions: We report a rare case of thyroid follicular adenoma with bizarre nuclei. In contrast to previous reports of this tumor, our patient showed a p53 wild-type pattern using immunohistochemistry. More studies are needed to better understand the etiology and clinical prognosis of this tumor.

16.
Cureus ; 15(10): e47261, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38021638

RESUMEN

Background Medical education often overlooks the significance of design and innovation literacy, resulting in a knowledge gap in undergraduate medical education (UME) regarding formal training in these areas. Incorporating innovation into UME's core curriculum is crucial as future physicians will encounter evolving technologies, and fostering a transdisciplinary approach can enable collaborative problem-solving and improve patient health outcomes. Methodology We developed a comprehensive medical biodesign curriculum focused on innovation, including problem identification, prototype testing, and product commercialization. Participants were selected based on applications, interviews, and diverse criteria. A survey was conducted before and after the program to assess students' biodesign experiences and knowledge, with data analyzed using descriptive statistics and paired t-tests. Results Of the 41 participants, 24 (58.5%) completed both pre- and post-program surveys. These five-point Likert surveys showed a significant shift from pre-program to responses demonstrating increased "comfort levels in explaining and applying biodesign principles" (p < 0.0001). Specifically, the "comfort level in taking a product to market" increased from 33% to 67% (p = 0.01), while the "comfort level in applying the biodesign process" increased from 29% to 92% (p < 0.0001). Moreover, 58.3% of participants expressed interest in continuing their current projects, and 70.8% of students stated feeling confident in generating ideas and solutions with their team members. Conclusions The medical biodesign curriculum demonstrated success in exposing undergraduate medical and engineering students to the concepts of medical innovation and biodesign. The program has led to a significant improvement in students' knowledge and comfort levels in applying the biodesign process and taking a product to market. The high level of interest and participation in the program highlight the need for incorporating innovative training in UME to foster creativity and prepare future physicians to contribute to the advancements in healthcare.

17.
J Chromatogr A ; 1708: 464327, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37660562

RESUMEN

Oligonucleotides have become an essential modality for a variety of therapeutic approaches, including cell and gene therapies. Rapid progress in the field has attracted significant research in designing novel oligonucleotide chemistries and structures. Beyond their polar nature, the length of large RNAs and presence of numerous diastereomers for phosphorothioate (PS)-modified RNAs pose heightened challenges for their characterization. In this study, the stereochemistry of a fully-modified antisense oligonucleotide (ASO) and partially-modified guide RNAs (gRNAs) was investigated using HILIC and orthogonal techniques. The profiles of three lots of a fully-modified ASO with PS linkages were compared using ion-pairing RPLC (IPRP) and HILIC. Interestingly, three isomer peaks were partially resolved by HILIC for two lots while only one peak was observed on the IPRP profile. Model oligonucleotides having the same sequence of the five nucleotides incorporated to the 3'-end of the gRNA but differing in their number and position of PS linkages were investigated by HILIC, IPRP, ion mobility spectrometry-mass spectrometry (IM-MS) and nuclear magnetic resonance (NMR). An strategy was ultimately designed to aid in the characterization of gRNA stereochemistry. Ribonuclease (RNase) T1 digestion enabled the characterization of gRNA diastereomers by reducing their number from 32 at the gRNA intact level to 4 or 8 at the fragment level. To our knowledge, this is the first time that HILIC has successfully been utilized for the profiling of diastereomers for various oligonucleotide formats and chemical modifications.


Asunto(s)
Oligonucleótidos Antisentido , Oligonucleótidos , Cromatografía Liquida , Espectrometría de Masas , ARN
18.
Blood Cancer J ; 13(1): 142, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37696819

RESUMEN

FLT3 is the most frequently mutated gene in acute myeloid leukemia (AML), with FLT3 internal tandem duplication (ITD) mutations being associated with a more aggressive clinical course. While two large, randomized clinical trials have shown a survival benefit with the frontline use of an oral FLT3 inhibitor (midostaurin or quizartinib) in patients with FLT3-mutated AML, the role of FLT3 inhibitors in older adults with newly diagnosed FLT3-mutated AML remains unclear. A definitive improvement in survival has not been observed in intensively treated patients over 60 years of age receiving frontline FLT3 inhibitors. Furthermore, many patients with FLT3-mutated AML are unsuitable for intensive chemotherapy due to age and/or comorbidities, and this population represents a particular unmet need. For these older patients who are unfit for intensive approaches, azacitidine + venetoclax is a new standard of care and is used by many clinicians irrespective of FLT3 mutation status. However, FLT3-ITD mutations confer resistance to venetoclax and are a well-established mechanism of relapse to lower-intensity venetoclax-based regimens, leading to short durations of remission and poor survival. Preclinical and clinical data suggest synergy between FLT3 inhibitors and venetoclax, providing rationale for their combination. Novel strategies to safely incorporate FLT3 inhibitors into the standard hypomethylating agent + venetoclax backbone are now being explored in this older, less fit population with newly diagnosed FLT3-mutated AML, with encouraging early results. Herein, we discuss the frontline use of FLT3 inhibitors in older adults with FLT3-mutated AML, including the potential role of FLT3 inhibitors in combination with intensive chemotherapy and as part of novel, lower-intensity doublet and triplet regimens in this older population.


Asunto(s)
Leucemia Mieloide Aguda , Sulfonamidas , Humanos , Persona de Mediana Edad , Anciano , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Mutación , Tirosina Quinasa 3 Similar a fms/genética
19.
Artículo en Inglés | MEDLINE | ID: mdl-37735518

RESUMEN

BACKGROUND: Aircraft noise is a key concern for communities surrounding airports, with increasing evidence for health effects and inequitable distributions of exposure. However, there have been limited national-scale assessments of aircraft noise exposure over time and across noise metrics, limiting evaluation of population exposure patterns. OBJECTIVE: We evaluated national-scale temporal trends in aviation noise exposure by airport characteristics and across racial/ethnic populations in the U.S. METHODS: Noise contours were modeled for 90 U.S. airports in 5-year intervals between 1995 and 2015 using the Federal Aviation Administration's Aviation Environmental Design Tool. We utilized linear fixed effects models to estimate changes in noise exposure areas for day-night average sound levels (DNL) of 45, 65, and a nighttime equivalent sound level (Lnight) of 45 A-weighted decibels (dB[A]). We used group-based trajectory modeling to identify distinct groups of airports sharing underlying characteristics. We overlaid noise contours and Census tract data from the U.S. Census Bureau and American Community Surveys for 2000 to 2015 to estimate exposure changes overall and by race/ethnicity. RESULTS: National-scale analyses showed non-monotonic trends in mean exposed areas that peaked in 2000, followed by a 37% decrease from 2005 to 2010 and a subsequent increase in 2015. We identified four distinct trajectory groups of airports sharing latent characteristics related to size and activity patterns. Those populations identifying as minority (e.g., Hispanic/Latino, Black/African American, Asian) experienced higher proportions of exposure relative to their subgroup populations compared to non-Hispanic or White populations across all years, indicating ethnic and racial disparities in airport noise exposure that persist over time. SIGNIFICANCE: Overall, these data identified differential exposure trends across airports and subpopulations, helping to identify vulnerable communities for aviation noise in the U.S. IMPACT STATEMENT: We conducted a descriptive analysis of temporal trends in aviation noise exposure in the U.S. at a national level. Using data from 90 U.S. airports over a span of two decades, we characterized the noise exposure trends overall and by airport characteristics, while estimating the numbers of exposed by population demographics to help identify the impact on vulnerable communities who may bear the burden of aircraft noise exposure.

20.
Anal Chem ; 95(40): 15017-15024, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37747361

RESUMEN

Health authorities have highlighted the need to determine oligonucleotide aggregates. However, existing technologies have limitations that have prevented the reliable analysis of size variants for large nucleic acids and lipid nanoparticles (LNPs). In this work, nucleic acid and LNP aggregation was examined using prototype, low adsorption ultrawide pore size exclusion chromatography (SEC) columns. A preliminary study was conducted to determine the column's physicochemical properties. A large difference in aggregate content (17.8 vs 59.7 %) was found for a model messenger RNA (mRNA) produced by different manufacturers. We further investigated the nature of the aggregates via a heat treatment. Interestingly, thermal stress irreversibly decreased the amount of aggregates from 59.7 to 4.1% and increased the main peak area 3.3-fold. To the best of our knowledge, for the first time, plasmid DNA topological forms and multimers were separated by analytical SEC. The degradation trends were compared to the data obtained with an anion exchange chromatography method. Finally, unconjugated and fragment antigen-binding (Fab)-guided LNPs were analyzed and their elution times were plotted against their sizes as measured by DLS. Multi-angle light scattering (MALS) was coupled to SEC in order to gain further insights on large species eluting before the LNPs, which were later identified as self-associating LNPs. This study demonstrated the utility of ultrawide pore SEC columns in characterizing the size variants of large nucleic acid therapeutics and LNPs.

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