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1.
ACS EST Air ; 1(1): 52-61, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-39166528

RESUMEN

Uptake coefficients of n-butylamine (BA) on solid succinic (SA) and glutaric acids (GA) from 298 to 177 K were measured using a newly combined Knudsen cell temperature-programmed desorption apparatus. The uptake coefficients on SA increase monotonically from (1.9 ± 0.5) × 10-4 at 298 K to 0.14 ± 0.05 at 177 K (errors represent 2σ statistical errors, overall errors are estimated to be ±60%). This is consistent with a surface reaction mechanism to form solid aminium carboxylate. In contrast, the uptake coefficients on GA increase from 0.11 ± 0.04 at 298 K to 0.25 ± 0.04 at 248 K but then decrease to 0.030 ± 0.010 at 177 K. This unusual trend in temperature dependence of the uptake coefficient is due to formation of an ionic liquid (IL) layer upon the surface reaction of BA with GA, leading to a competition between the rate of desorption of BA and the rates of diffusion and reaction within the IL. Overall, the kinetic multi-layer model of aerosol surface and bulk chemistry (KM-SUB) satisfactorily reproduces these unique trends. This work provides mechanistic insight and predictive capability for the temperature-dependence of reactive uptake processes involving multiple phase changes upon surface reaction.

2.
Phys Chem Chem Phys ; 26(35): 23264-23276, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39205494

RESUMEN

Understanding growth mechanisms for particles in air is fundamental to developing a predictive capability for their impacts on human health, visibility, and climate. In the case of highly viscous semi-solid or solid particles, the likelihood of impinging gases being taken up to grow the particle will be influenced by the initial uptake coefficient and by the residence time of the adsorbed gas on the surface. Here, a new approach that combines Knudsen cell capabilities for gas uptake measurements with temperature programmed desorption (TPD) for binding energy measurements of gases is described. The application of this unique capability to the uptake of organic gases on silica demonstrates its utility and the combination of thermodynamic and kinetic data that can be obtained. Lower limits to the initial net uptake coefficients at 170 K are (3.0 ± 0.6) × 10-3, (4.9 ± 0.6) × 10-3 and (4.3 ± 0.8) × 10-3 for benzene, 1-chloropentane, and methanol, respectively, and are reported here for the first time. The uptake data demonstrated that the ideal gas lattice model was appropriate, which informed the analysis of the TPD data. From the thermal desorption measurements, desorption energies of 34.6 ± 2.5, 45.8 ± 5.5, and 40.0 ± 5.6 kJ mol-1 (errors are 1σ) are obtained for benzene, 1-chloropentane, and methanol, respectively, and show good agreement with previously reported measurements. A multiphase kinetics model was applied to quantify uptake, desorption, and diffusion through the particle multilayers and hence extract desorption kinetics. Implications for uptake of organics on silica surfaces in the atmosphere and the utility of this system for determining relationships between residence times of organic gases and particle surfaces of varying composition are discussed in the context of developing quantitative predictions for growth of aerosol particles in air.

3.
Support Care Cancer ; 32(8): 554, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066890

RESUMEN

PURPOSE: Common side effects of taxane chemotherapy are nail toxicity and peripheral neuropathy (CIPN) causing severe impact on the quality of life. Different methods of cryotherapy to prevent these side effects have been tested. We investigated the use of machine-controlled cooling of hands and feet to reduce nail toxicity and CIPN in patients receiving taxane chemotherapy. METHODS: Patients receiving Docetaxel (planned dose ≥ 300 mg/m2) or Paclitaxel (planned dose ≥ 720 mg/m2 - ) in the adjuvant or palliative setting of different cancers were included. The dominant hand and foot were cooled to approximately 10 °C using the Hilotherapy machine. The contralateral hand and foot were used as intrapatient comparison. The primary endpoint was the occurrence of any CIPN due to paclitaxel or nail toxicity due to Docetaxel. Both the intention to treat population (ITT) and the per protocol population (PPP) were analyzed. RESULTS: A total of 69 patients, 21 treated with Docetaxel and 48 with Paclitaxel, were included at our centre between 08/2020 and 08/2022. Nail toxicity due to Docetaxel was overall not significantly improved by cooling in the ITT or PPP but a significant benefit across visits was found for the ITT. CIPN due to Paclitaxel was numerically better in the ITT and significantly better in the PPP. A significant benefit of cooling on CIPN occurrence across visits was found for the ITT and the PPP. Cooling was very well tolerated. CONCLUSION: Cooling of hands and feet has a clinically meaningful impact on reducing occurrence of CIPN and nail toxicity on treatment with taxanes. Effects are more significant over time and are dose dependent. TRIAL REGISTRATION NUMBER: 2020-00381. Date of registration. 24th February 2020.


Asunto(s)
Docetaxel , Enfermedades de la Uña , Paclitaxel , Enfermedades del Sistema Nervioso Periférico , Humanos , Femenino , Estudios Prospectivos , Persona de Mediana Edad , Masculino , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/prevención & control , Anciano , Docetaxel/administración & dosificación , Docetaxel/efectos adversos , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Enfermedades de la Uña/terapia , Enfermedades de la Uña/inducido químicamente , Neoplasias/tratamiento farmacológico , Adulto , Taxoides/efectos adversos , Taxoides/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/administración & dosificación , Crioterapia/métodos , Calidad de Vida
4.
Inflamm Bowel Dis ; 30(Supplement_2): S5-S18, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38778627

RESUMEN

Preclinical human inflammatory bowel disease (IBD) mechanisms is one of 5 focus areas of the Challenges in IBD Research 2024 document, which also includes environmental triggers, novel technologies, precision medicine, and pragmatic clinical research. Herein, we provide a comprehensive overview of current gaps in inflammatory bowel diseases research that relate to preclinical research and deliver actionable approaches to address them with a focus on how these gaps can lead to advancements in IBD interception, remission, and restoration. The document is the result of multidisciplinary input from scientists, clinicians, patients, and funders and represents a valuable resource for patient-centric research prioritization. This preclinical human IBD mechanisms section identifies major research gaps whose investigation will elucidate pathways and mechanisms that can be targeted to address unmet medical needs in IBD. Research gaps were identified in the following areas: genetics, risk alleles, and epigenetics; the microbiome; cell states and interactions; barrier function; IBD complications (specifically fibrosis and stricturing); and extraintestinal manifestations. To address these gaps, we share specific opportunities for investigation for basic and translational scientists and identify priority actions.


To address the unmet medical needs of patients with inflammatory bowel diseases (IBD) and move toward cures, preclinical human-relevant research must center on mechanistic questions pertinent to patients with IBD in the 3 areas of disease interception, remission, and restoration.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Humanos , Enfermedades Inflamatorias del Intestino/microbiología , Animales , Microbioma Gastrointestinal , Investigación Biomédica , Medicina de Precisión/métodos
5.
Invest Ophthalmol Vis Sci ; 65(5): 27, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38758638

RESUMEN

Purpose: To demonstrate the first near-infrared adaptive optics fluorescence lifetime imaging ophthalmoscopy (NIR-AOFLIO) measurements in vivo of the human retinal pigment epithelial (RPE) cellular mosaic and to visualize lifetime changes at different retinal eccentricities. Methods: NIR reflectance and autofluorescence were captured using a custom adaptive optics scanning light ophthalmoscope in 10 healthy subjects (23-64 years old) at seven eccentricities and in two eyes with retinal abnormalities. Repeatability was assessed across two visits up to 8 weeks apart. Endogenous retinal fluorophores and hydrophobic whole retinal extracts of Abca4-/- pigmented and albino mice were imaged to probe the fluorescence origin of NIR-AOFLIO. Results: The RPE mosaic was resolved at all locations in five of seven younger subjects (<35 years old). The mean lifetime across near-peripheral regions (8° and 12°) was longer compared to near-foveal regions (0° and 2°). Repeatability across two visits showed moderate to excellent correlation (intraclass correlation: 0.88 [τm], 0.75 [τ1], 0.65 [τ2], 0.98 [a1]). The mean lifetime across drusen-containing eyes was longer than in age-matched healthy eyes. Fluorescence was observed in only the extracts from pigmented Abca4-/- mouse. Conclusions: NIR-AOFLIO was repeatable and allowed visualization of the RPE cellular mosaic. An observed signal in only the pigmented mouse extract infers the fluorescence signal originates predominantly from melanin. Variations observed across the retina with intermediate age-related macular degeneration suggest NIR-AOFLIO may act as a functional measure of a biomarker for in vivo monitoring of early alterations in retinal health.


Asunto(s)
Oftalmoscopía , Imagen Óptica , Epitelio Pigmentado de la Retina , Humanos , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/metabolismo , Oftalmoscopía/métodos , Adulto , Persona de Mediana Edad , Animales , Femenino , Ratones , Masculino , Adulto Joven , Imagen Óptica/métodos , Reproducibilidad de los Resultados , Rayos Infrarrojos , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Angiografía con Fluoresceína/métodos
6.
JMIR Hum Factors ; 11: e53194, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717809

RESUMEN

BACKGROUND: Care partners of people with serious illness experience significant challenges and unmet needs during the patient's treatment period and after their death. Learning from others with shared experiences can be valuable, but opportunities are not consistently available. OBJECTIVE: This study aims to design and prototype a regional, facilitated, and web-based peer support network to help active and bereaved care partners of persons with serious illness be better prepared to cope with the surprises that arise during serious illness and in bereavement. METHODS: An 18-member co-design team included active care partners and those in bereavement, people who had experienced serious illness, regional health care and support partners, and clinicians. It was guided by facilitators and peer network subject-matter experts. We conducted design exercises to identify the functions and specifications of a peer support network. Co-design members independently prioritized network specifications, which were incorporated into an early iteration of the web-based network. RESULTS: The team prioritized two functions: (1) connecting care partners to information and (2) facilitating emotional support. The design process generated 24 potential network specifications to support these functions. The highest priorities included providing a supportive and respectful community; connecting people to trusted resources; reducing barriers to asking for help; and providing frequently asked questions and responses. The network platform had to be simple and intuitive, provide technical support for users, protect member privacy, provide publicly available information and a private discussion forum, and be easily accessible. It was feasible to enroll members in the ConnectShareCare web-based network over a 3-month period. CONCLUSIONS: A co-design process supported the identification of critical features of a peer support network for care partners of people with serious illnesses in a rural setting, as well as initial testing and use. Further testing is underway to assess the long-term viability and impact of the network.


Asunto(s)
Internet , Grupo Paritario , Apoyo Social , Humanos , Cuidadores/psicología , Enfermedad Crítica/psicología
7.
J Phys Ther Educ ; 38(2): 107-115, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38758175

RESUMEN

INTRODUCTION: Despite a long history of using human donor dissection (HDD) for physical therapy (PT) anatomy education, there are no PT guidelines that require HDD. The purpose of this quantitative causal-comparative study was to determine if Doctor of Physical Therapy students who used HDD had different grades both within anatomy and within courses that require retention and application of anatomical knowledge (kinesiology and a foundational musculoskeletal course) compared with those who used virtual 3-dimensional anatomical software (VAS). REVIEW OF LITERATURE: Numerous factors affect the decision to use HDD within PT anatomy, and few PT studies have compared the effectiveness of VAS to HDD. SUBJECTS: All students who took anatomy in an entry-level PT program from 2018 to 2021 (232 total students, 115 who used HDD in 2018-2019 and 117 who used VAS in 2020-2021). METHODS: Mann-Whitney tests were used to compare anatomy grades (course, written examination, and practical examination) and future grades in kinesiology and a foundational musculoskeletal course for students who used HDD or VAS. RESULTS: Physical therapy students who used VAS had statistically significant higher anatomy course grades (VAS 93.81% ± 4.99% to HDD 92.20% ± 4.53%) and higher practical examination grades (VAS 97.43% ± 2.91% to HDD 93.55% ± 4.39%) compared with those who used HDD. However, there were no significant differences between groups on written anatomy examinations (VAS 89.42% ± 7.21% to HDD 90.40% ± 4.94%), kinesiology grades (VAS 91.86% ± 4.52% to HDD 92.80% ± 4.27%), or foundational musculoskeletal grades (VAS 89.50% ± 3.89% to HDD 89.77% ± 3.83%). DISCUSSION AND CONCLUSION: The causal-comparative study design prevents concluding that PT student grade differences were due exclusively to either anatomy laboratory method. It does provide preliminary evidence that the PT anatomy laboratory method did not practically affect anatomy performance or long-term application of anatomy knowledge in future coursework.


Asunto(s)
Anatomía , Disección , Humanos , Anatomía/educación , Evaluación Educacional , Cadáver , Masculino , Especialidad de Fisioterapia/educación , Femenino
8.
Acad Pathol ; 11(2): 100111, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560424

RESUMEN

Entrustable professional activities (EPAs) are observable activities that define the practice of medicine and provide a framework of evaluation that has been incorporated into US medical school curricula in both undergraduate and graduate medical education. This manuscript describes the development of an entrustment scale and formative and summative evaluations for pathology EPAs, outlines a process for faculty development that was employed in a pilot study implementing two Anatomic Pathology and two Clinical Pathology EPAs in volunteer pathology residency programs, and provides initial validation data for the proposed pathology entrustment scales. Prior to implementation, faculty development was necessary to train faculty on the entrustment scale for each given activity. A "train the trainer" model used performance dimension training and frame of reference training to train key faculty at each institution. The session utilized vignettes to practice determination of entrustment ratings and development of feedback for trainees as to strengths and weaknesses in the performance of these activities. Validity of the entrustment scale is discussed using the Messick framework, based on concepts of content, response process, and internal structure. This model of entrustment scales, formative and summative assessments, and faculty development can be utilized for any pathology EPA and provides a roadmap for programs to design and implement EPA assessments into pathology residency training.

9.
Acad Pathol ; 11(2): 100110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560425

RESUMEN

Entrustable professional activities (EPAs) are observable clinical skills and/or procedures that have been introduced into medical education at the student and resident levels in most specialties to determine readiness to advance into residency or independent practice, respectively. This publication describes the process and outcomes of a pilot study looking at the feasibility of using two anatomic pathology and two clinical pathology EPAs in pathology residency in 6 pathology residency programs that volunteered for the study. Faculty development on EPAs and their assessment was provided to pilot program faculty, and EPA assessment tools were developed and used by the pilot programs. Pre- and post-study surveys were given to participating residents, faculty, and program directors to gauge baseline practices and to gather feedback on the EPA implementation experience. Results demonstrated overall good feasibility in implementing EPAs. Faculty acceptance of EPAs varied and was less than that of program directors. Residents reported a significant increase in the frequency with which faculty provided formative assessments that included specific examples of performance and specific ways to improve, as well as increased frequency with which faculty provided summative assessments that included specific ways to improve. EPAs offered the most benefit in setting clear expectations for performance of each task, for providing more specific feedback to residents, and in increasing Program director's understanding of resident strengths abilities and weaknesses.

10.
Invest Ophthalmol Vis Sci ; 65(4): 27, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630675

RESUMEN

Purpose: Fluorescence lifetime ophthalmoscopy (FLIO) is an emerging clinical modality that could provide biomarkers of retinal health beyond fluorescence intensity. Adaptive optics (AO) ophthalmoscopy provides the confocality to measure fluorescence lifetime (FL) primarily from the retinal pigment epithelium (RPE) whereas clinical FLIO has greater influence from fluorophores in the inner retina and lens. Adaptive optics fluorescence lifetime ophthalmoscopy (AOFLIO) measures of FL in vivo could provide insight into RPE health at different stages of disease. In this study, we assess changes in pentosan polysulfate sodium (PPS) toxicity, a recently described toxicity that has clinical findings similar to advanced age-related macular degeneration. Methods: AOFLIO was performed on three subjects with PPS toxicity (57-67 years old) and six age-matched controls (50-64 years old). FL was analyzed with a double exponential decay curve fit and with phasor analysis. Regions of interest (ROIs) were subcategorized based on retinal features on optical coherence tomography (OCT) and compared to age-matched controls. Results: Twelve ROIs from PPS toxicity subjects met the threshold for analysis by curve fitting and 15 ROIs met the threshold for phasor analysis. Subjects with PPS toxicity had prolonged FL compared to age-matched controls. ROIs of RPE degeneration had the longest FLs, with individual pixels extending longer than 900 ps. Conclusions: Our study shows evidence that AOFLIO can provide meaningful information in outer retinal disease beyond what is obtainable from fluorescence intensity alone. More studies are needed to determine the prognostic value of AOFLIO.


Asunto(s)
Degeneración Retiniana , Epitelio Pigmentado de la Retina , Humanos , Persona de Mediana Edad , Anciano , Poliéster Pentosan Sulfúrico , Retina , Oftalmoscopía/métodos , Tomografía de Coherencia Óptica/métodos , Angiografía con Fluoresceína/métodos
11.
Acad Pathol ; 11(1): 100107, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38433776

RESUMEN

The number of graduating allopathic (MD) medical students matching into pathology has declined in recent years, while the number of osteopathic (DO) medical students has increased modestly, given the rapid expansion of osteopathic medical schools. Nonscholarly publications and materials on the internet often perpetuate negative perceptions of osteopathic physicians. Anecdotally, perspectives exist that some pathology residency programs are not DO-friendly; however, the reasons and how widespread an effect this might be are unclear. Our survey queried pathology chairs and residency program directors about their perceptions of osteopathic applicants and their knowledge of osteopathic medical school/training in general. This study utilized two similar, parallel surveys of pathology chairs and residency program directors with general questions structured around the perceptions and knowledge of both allopathic and osteopathic physicians, their medical training, and the consideration of osteopathic applicants to pathology residency. Pathology residency leaders acknowledge some negative perceptions of osteopathic physicians in the medical profession, the news, and social media. They also have some knowledge and perception gaps regarding osteopathic training and applicants, although experience with training osteopathic physicians as residents has been equivalent to that with allopathic physicians, and consideration appears to be fairly equal for osteopathic applicants. Even though negative perceptions of osteopathic physicians persist in news and social media, our surveys demonstrate that the leadership of pathology residency programs does not hold the same degree of bias and that DOs perform well in allopathic pathology residency programs without evidence of inferior outcomes.

12.
Arch Pathol Lab Med ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38528091

RESUMEN

CONTEXT.­: As pathologists retire and leave the field, it is critical to accurately capture employment trends for new-in-practice pathologists. There is always interest in the job market for newly graduated pathology trainees and prospective pathology trainees, but it is unclear how the COVID-19 pandemic may have affected the job search experience. OBJECTIVE.­: To provide an update on trends gleaned from a survey of pathology graduates' job search experiences during the COVID-19 pandemic. DESIGN.­: We analyzed data from an annual job search survey sent by the College of American Pathologists Graduate Medical Education Committee between 2020 and 2022 to College of American Pathologists junior members and fellows in practice 3 years or less actively looking for a nonfellowship position. Various indicators of the job search experience were compared year to year and with the data previously published 2017 to 2019 and 2012 to 2016. RESULTS.­: Analysis revealed continued positive trends between the 2020 to 2022 data and the data from 2017 to 2019 and 2012 to 2016. This includes continued ease in finding positions, continued availability of jobs in the subspecialty of choice, continued satisfaction with the positions accepted, and, notably, higher starting salaries. CONCLUSIONS.­: Despite the many challenges of the COVID-19 pandemic, job market trends for newly graduated pathology trainees continue to be favorable with respect to multiple indicators compared with 2 prior periods, 2017 to 2019 and 2012 to 2016.

13.
Nat Commun ; 15(1): 1173, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38332002

RESUMEN

Respiratory syncytial virus (RSV) is a common cause of acute lower respiratory tract infection in infants, older adults and the immunocompromised. Effective directly acting antivirals are not yet available for clinical use. To address this, we screen the ReFRAME drug-repurposing library consisting of 12,000 small molecules against RSV. We identify 21 primary candidates including RSV F and N protein inhibitors, five HSP90 and four IMPDH inhibitors. We select lonafarnib, a licensed farnesyltransferase inhibitor, and phase III candidate for hepatitis delta virus (HDV) therapy, for further follow-up. Dose-response analyses and plaque assays confirm the antiviral activity (IC50: 10-118 nM). Passaging of RSV with lonafarnib selects for phenotypic resistance and fixation of mutations in the RSV fusion protein (T335I and T400A). Lentiviral pseudotypes programmed with variant RSV fusion proteins confirm that lonafarnib inhibits RSV cell entry and that these mutations confer lonafarnib resistance. Surface plasmon resonance reveals RSV fusion protein binding of lonafarnib and co-crystallography identifies the lonafarnib binding site within RSV F. Oral administration of lonafarnib dose-dependently reduces RSV virus load in a murine infection model using female mice. Collectively, this work provides an overview of RSV drug repurposing candidates and establishes lonafarnib as a bona fide fusion protein inhibitor.


Asunto(s)
Dibenzocicloheptenos , Piridinas , Infecciones por Virus Sincitial Respiratorio , Animales , Femenino , Ratones , Reposicionamiento de Medicamentos , Piperidinas/farmacología , Piperidinas/uso terapéutico , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/química
14.
J Lipid Res ; 65(3): 100512, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38295986

RESUMEN

Ebola virus (EBOV) causes severe hemorrhagic fever in humans and is lethal in a large percentage of those infected. The EBOV matrix protein viral protein 40 kDa (VP40) is a peripheral binding protein that forms a shell beneath the lipid bilayer in virions and virus-like particles (VLPs). VP40 is required for virus assembly and budding from the host cell plasma membrane. VP40 is a dimer that can rearrange into oligomers at the plasma membrane interface, but it is unclear how these structures form and how they are stabilized. We therefore investigated the ability of VP40 to form stable oligomers using in vitro and cellular assays. We characterized two lysine-rich regions in the VP40 C-terminal domain (CTD) that bind phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) and play distinct roles in lipid binding and the assembly of the EBOV matrix layer. The extensive analysis of VP40 with and without lipids by hydrogen deuterium exchange mass spectrometry revealed that VP40 oligomers become extremely stable when VP40 binds PI(4,5)P2. The PI(4,5)P2-induced stability of VP40 dimers and oligomers is a critical factor in VP40 oligomerization and release of VLPs from the plasma membrane. The two lysine-rich regions of the VP40 CTD have different roles with respect to interactions with plasma membrane phosphatidylserine (PS) and PI(4,5)P2. CTD region 1 (Lys221, Lys224, and Lys225) interacts with PI(4,5)P2 more favorably than PS and is important for VP40 extent of oligomerization. In contrast, region 2 (Lys270, Lys274, Lys275, and Lys279) mediates VP40 oligomer stability via lipid interactions and has a more prominent role in release of VLPs.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Humanos , Ebolavirus/metabolismo , Fiebre Hemorrágica Ebola/metabolismo , Lisina/metabolismo , Sitios de Unión , Lípidos , Unión Proteica
15.
Elife ; 122023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38126343

RESUMEN

Yes-associated protein (YAP), the downstream effector of the evolutionarily conserved Hippo pathway, promotes cellular proliferation and coordinates certain regenerative responses in mammals. Small molecule activators of YAP may, therefore, display therapeutic utility in treating disease states involving insufficient proliferative repair. From a high-throughput chemical screen of the comprehensive drug repurposing library ReFRAME, here we report the identification of SM04690, a clinical stage inhibitor of CLK2, as a potent activator of YAP-driven transcriptional activity in cells. CLK2 inhibition promotes alternative splicing of the Hippo pathway protein AMOTL2, producing an exon-skipped gene product that can no longer associate with membrane-bound proteins, resulting in decreased phosphorylation and membrane localization of YAP. This study reveals a novel mechanism by which pharmacological perturbation of alternative splicing inactivates the Hippo pathway and promotes YAP-dependent cellular growth.


Asunto(s)
Proteínas Serina-Treonina Quinasas , Transducción de Señal , Animales , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/fisiología , Factores de Transcripción/metabolismo , Empalme Alternativo , Proteínas Señalizadoras YAP , Proteínas de la Membrana/metabolismo , Mamíferos/metabolismo
16.
JCI Insight ; 8(17)2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37681413

RESUMEN

Osteoarthritis (OA) is the most common joint disorder, and disease-modifying OA drugs (DMOADs) represent a major need in OA management. Krüppel-like factor 4 (KLF4) is a central transcription factor upregulating regenerative and protective functions in joint tissues. This study was aimed to identify small molecules activating KLF4 expression and to determine functions and mechanisms of the hit compounds. High-throughput screening (HTS) with 11,948 clinical-stage compounds was performed using a reporter cell line detecting endogenous KLF4 activation. Eighteen compounds were identified through the HTS and confirmed in a secondary screen. After testing in SW1353 chondrosarcoma cells and human chondrocytes, mocetinostat - a class I selective histone deacetylase (HDAC) inhibitor - had the best profile of biological activities. Mocetinostat upregulated cartilage signature genes in human chondrocytes, meniscal cells, and BM-derived mesenchymal stem cells, and it downregulated hypertrophic, inflammatory, and catabolic genes in those cells and synoviocytes. I.p. administration of mocetinostat into mice reduced severity of OA-associated changes and improved pain behaviors. Global gene expression and proteomics analyses revealed that regenerative and protective effects of mocetinostat were dependent on peroxisome proliferator-activated receptor γ coactivator 1-α. These findings show therapeutic and protective activities of mocetinostat against OA, qualifying it as a candidate to be used as a DMOAD.


Asunto(s)
Neoplasias Óseas , Osteoartritis , Humanos , Animales , Ratones , Factor 4 Similar a Kruppel , Osteoartritis/tratamiento farmacológico , Inflamación , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico
17.
Cureus ; 15(4): e37492, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37187666

RESUMEN

Background Due to the non-malignant and slow-growing nature of many meningiomas, surveillance with serial magnetic resonance imaging (MRI) serves as an acceptable management plan. However, repeated imaging with gold-standard contrast-based studies may lead to contrast-associated adverse effects. Non-gadolinium T2 sequences may serve as a suitable alternative without the risk of adverse effects of contrast. Thus, this study sought to investigate the agreement between post-contrast T1 and non-gadolinium T2 MRI sequences in the measurement of meningioma growth. Methodology The Virginia Commonwealth University School of Medicine (VCU SOM) brain tumor database was used to create a cohort of meningioma patients and determine the number of patients who had T1 post-contrast imaging accompanied by readily measurable imaging from either T2 fast spin echo (FSE) or T2 fluid-attenuated inversion recovery (FLAIR) sequences. Measurements of the largest axial and perpendicular diameters of each tumor were conducted by two independent observers using T1 post-contrast, T2 FSE, and T2 FLAIR imaging series. Lin's concordance correlation coefficient (CCC) was calculated to assess inter-rater reliability between observers and agreement between measurements of tumor diameter among the different imaging sequences. Results In total, 33 patients (average age = 72.1 ± 12.9 years, 90% female) with meningiomas were extracted from our database, with 22 (66.7%) undergoing T1 post-contrast imaging accompanied with readily measurable imaging from T2 FSE and/or T2 FLAIR sequences. The inter-rater reliability between the measurements of T1 axial and perpendicular diameters was 0.96 (95% confidence interval (CI) = 0.92-0.98) and 0.92 (95% CI = 0.83-0.97), respectively. The inter-rater reliability between the measurements of T2 axial perpendicular diameters was 0.93 (95% = CI 0.92-0.97) and 0.89 (95% CI = 0.74-0.95), respectively. The agreements between the measurement of T1 and T2 FSE axial diameter by each observer were 0.97 (95% CI = 0.93-0.98) and 0.92 (95% CI = 0.81-0.97). The agreements between the measurements of T1 and T2 FSE perpendicular diameter measurements by each observer were 0.98 (95% CI = 0.95-0.99) and 0.88 (95% CI = 0.73-0.95). Conclusions Two-thirds of our patients had meningiomas that were readily measurable on either T2 FSE or T2 FLAIR sequences. Additionally, there was excellent inter-rater reliability between the observers in our study as well as an agreement between individual measurements of T1 post-contrast and T2 FSE tumor diameters. These findings suggest that T2 FSE may serve as a safe and similarly effective surveillance method for the long-term management of meningioma patients.

18.
Acad Pathol ; 10(2): 100074, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124363

RESUMEN

Medical student interest and pursuit of a career in pathology have been steadily declining since 2015. We conducted three separate surveys of medical students to better understand these trends. In our first survey, we focused on assessing U.S. allopathic medical students understanding and perceptions of pathology. We later surveyed U.S. osteopathic medical students as a companion to the allopathic medical student survey, in which many similarities were discovered with some key differences. In our final survey, we specifically looked at curriculum differences between the U.S. allopathic medical schools that graduate the most students who enter pathology training programs (Group 1) versus those schools that graduate the fewest future pathologists (Group 2) to determine if the curriculum had an impact on medical student matriculation into pathology. Together, through these surveys, we were able to identify several remarkable recurring trends, presenting areas of targetable action. Here, we summarize themes from the three studies as well as a review of pertinent literature to offer best practices for exposing and engaging medical students to pathology and possibly recruiting students to consider pathology as a career.

19.
Acad Pathol ; 10(2): 100073, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124364

RESUMEN

There has been a significant decline in the number of United States allopathic medical students matching to pathology residency programs. Data acquired from the American Association of Medical Colleges (AAMC) show sustained variation in the medical school production of students who go on to pathology residency. When divided into groups based on the medical school's historical volume of graduates entering pathology, the schools in groups labeled Group 1 and Group 2 produced significantly higher and lower proportions of pathology residents, respectively. This study aimed to identify what medical school curriculum elements and other medical school characteristics might explain the differences observed in the AAMC data. The Dean or another undergraduate medical education contact from the Group 1 and Group 2 schools was invited to participate in an interview. Pathology Program Directors and Pathology Department Chairs were also included in communications. Thirty interviews were completed with equal numbers from each group. Interview questions probed pathology experiences, existence, and structure of a pathology interest group, options for post-sophomore fellowships, recent curriculum changes, and the extent of mentoring programs. Surprisingly, the curriculum does not appear to be a predictor of a medical school's production of students who enter pathology residency. A significantly greater percentage of Group 1 schools are public institutions compared to Group 2 schools. Other factors that may increase the number of students who go into pathology include mentoring, active learning versus observation, and post-sophomore fellowships or other opportunities to work in the capacity of a new pathology resident.

20.
bioRxiv ; 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37131806

RESUMEN

Yes-associated protein (YAP), the downstream effector of the evolutionarily conserved Hippo pathway, promotes cellular proliferation and coordinates certain regenerative responses in mammals. Small molecule activators of YAP may therefore display therapeutic utility in treating disease states involving insufficient proliferative repair. From a high-throughput chemical screen of the comprehensive drug repurposing library ReFRAME, here we report the identification of SM04690, a clinical stage inhibitor of CLK2, as a potent activator of YAP driven transcriptional activity in cells. CLK2 inhibition promotes alternative splicing of the Hippo pathway protein AMOTL2, producing an exon-skipped gene product that can no longer associate with membrane-bound proteins, resulting in decreased phosphorylation and membrane localization of YAP. This study reveals a novel mechanism by which pharmacological perturbation of alternative splicing inactivates the Hippo pathway and promotes YAP dependent cellular growth.

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