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1.
Gynecol Oncol ; 184: 236-242, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38382150

RESUMEN

INTRODUCTION: Endometrial cancer is the most commonly diagnosed female genital tract malignancy in the United States of America. Racial disparities surrounding this particular disease have been extensively investigated for over 26-years. We sought to determine if research in this area has led to any significant improvements in this disparity. METHODS: We performed a rapid systematic review of English language publications on racial disparities in endometrial cancer among African American (AAW) and white American women (WAW), from 1997 to 2023. We looked at trends in incidence and survival; impact of known poor prognostic factors (stage at diagnosis, histological subtypes, grade); co-morbidities; differences in treatment (surgery, radiation and chemotherapy); socioeconomic factors; differences in biological and genetic markers; and policies/declarations. RESULTS: During the period under review (1997-2023), there was a notable increase in both disease incidence (39%) and mortality (26%) rates for AAW, in comparison to WAW among whom the incidence rates increased by 2% and mortality rates rose, but 9% less than for AAW. It should be noted that the current incidence rate of 29.4% in AAW represent a reversal of what is was 26-years ago, when the incidence rate was 17.8%. In comparison to WAW, AAW had a higher prevalence of poor prognostic variables, more co-morbidities, lower income levels, less insurance coverage, and were more frequently under treated with surgery, chemotherapy and radiation. To date no actionable molecular/genetic markers have been identified. We were unable to locate any published recommendations or active programs of implementation strategies/policies designed to effectively mitigate the documented racial disparity. CONCLUSION: Racial disparities in disease incidence and mortality in endometrial cancer rates between WAW and AAW have widened during a 26-year period of robust research, suggesting that current research alone is not enough to eliminate this disparity. Based on this rapid systematic review we have identified and analyzed the impact of causation variables on this disparity. Additionally, we have made strong and pertinent recommendations for the benefit of mitigating this escalating racial disparity.

2.
Gynecol Oncol ; 185: 42-45, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38367302

RESUMEN

INTRODUCTION: The formative period of the specialty of gynecologic oncology was from 1968 to 1972 and became a board-certified specialty in 1973. During this formation there were no Black physicians participating in this process. We chronicle and document the incorporation of the first three board-certified Black physicians in the specialty of gynecologic oncology here for historical purposes. METHODS: We highlight the hostile climate experienced by Black physicians before and during the formation of gynecologic oncology, review the acceptance and training of the first three Black physicians in the specialty and recognize their significant contributions to the field. RESULTS: The biographies and the narrative of these men describe their impact and contribution to medicine. We chronicle the historic presence of the first board-certified Black gynecologic oncologists and pelvic surgeons in the United States. CONCLUSION: These three men represent the Black Founding Fathers of gynecologic oncology. Their perseverance in the face of adversity and commitment to excellence have left an indelible impact on the institutions that they developed, the individuals that they trained, and the patients that they served.

3.
Int J Gynaecol Obstet ; 165(2): 552-561, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37927080

RESUMEN

BACKGROUND: Following the launch of the World Health Organization's Strategy to accelerate the elimination of cervical cancer, diagnosis is expected to increase, especially in low- and middle-income countries (LMICs). A well-integrated surgical system is critical to treat cervical cancer. Two major approaches have been employed to build human capacity: task-sharing and training of gynecologic oncologists (GynOncs). OBJECTIVES: This review aimed to explore existing literature on capacity-building for surgical management of early-stage gynecologic cancers. SEARCH STRATEGY: The search strategy was registered on Open Science Framework (doi 10.17605/OSF.IO/GTRCB) and conducted on OVID Medline, Embase, Global Index Medicus, and Web of Science. Search results were exported and screened in COVIDENCE. SELECTION CRITERIA: Studies published in English, Spanish, French, and/or Portuguese conducted in LMIC settings evaluating capacity building, task-sharing, or outcomes following operation by subspecialists compared to specialists were included. DATA COLLECTION AND ANALYSIS: Results were synthesized using narrative synthesis approach with emergence of key themes by frequency. MAIN RESULTS: The scoping review identified 18 studies spanning our themes of interest: capacity building, subspecialized versus non-subspecialized care, and task-shifting/-sharing. CONCLUSIONS: A multilayered approach is critical to achieve the WHO Strategy to Eliminate Cervical Cancer. Capacity-building and task-sharing programs demonstrate encouraging results to meet this need; nevertheless, a standardized methodology is needed to evaluate these programs, their outcomes, and cost-effectiveness.


Asunto(s)
Países en Desarrollo , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/cirugía , Creación de Capacidad , Calidad de la Atención de Salud
5.
Nat Cell Biol ; 25(12): 1758-1773, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37919520

RESUMEN

Skeletal muscle stem and progenitor cells including those derived from human pluripotent stem cells (hPSCs) offer an avenue towards personalized therapies and readily fuse to form human-mouse myofibres in vivo. However, skeletal muscle progenitor cells (SMPCs) inefficiently colonize chimeric stem cell niches and instead associate with human myofibres resembling foetal niches. We hypothesized competition with mouse satellite cells (SCs) prevented SMPC engraftment into the SC niche and thus generated an SC ablation mouse compatible with human engraftment. Single-nucleus RNA sequencing of SC-ablated mice identified the absence of a transient myofibre subtype during regeneration expressing Actc1. Similarly, ACTC1+ human myofibres supporting PAX7+ SMPCs increased in SC-ablated mice, and after re-injury we found SMPCs could now repopulate into chimeric niches. To demonstrate ACTC1+ myofibres are essential to supporting PAX7 SMPCs, we generated caspase-inducible ACTC1 depletion human pluripotent stem cells, and upon SMPC engraftment we found a 90% reduction in ACTC1+ myofibres and a 100-fold decrease in PAX7 cell numbers compared with non-induced controls. We used spatial RNA sequencing to identify key factors driving emerging human niche formation between ACTC1+ myofibres and PAX7+ SMPCs in vivo. This revealed that transient regenerating human myofibres are essential for emerging niche formation in vivo to support PAX7 SMPCs.


Asunto(s)
Músculo Esquelético , Factor de Transcripción PAX7 , Regeneración , Células Satélite del Músculo Esquelético , Animales , Humanos , Ratones , Músculo Esquelético/fisiología , Factor de Transcripción PAX7/genética , Factor de Transcripción PAX7/metabolismo , Células Madre Pluripotentes , Células Satélite del Músculo Esquelético/fisiología
6.
J Sep Sci ; 46(21): e2300300, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37715328

RESUMEN

Pharmaceutical development currently relies on quality separation methods from early discovery through to line-of-site manufacturing. There have been significant advancements made regarding the column particle packing, internal diameter, length connectivity, the understanding of the impact key parameters like void volume, flow rate, and temperature all that affects the resultant separation quality, that is, resolution, peak shape, peak width, run time, and signal-to-noise ratio. There is however a strong need to establish better alternatives to large bulky high-performance liquid chromatography racks either for process analytical reaction monitoring or mass spectrometry analysis in establishing product quality. Compact, portable high-pressure liquid chromatography can be a more efficient alternative to traditional ultra-high pressure liquid chromatography and traditional liquid chromatography. The compact versatile instrument evaluated here allows good separation control with either the on-board column with fixed ultra-violet wavelength cartridge or for use with a high-resolution mass spectrometry. Significant space reduction results in greener lab spaces with improved energy efficiency for smaller labs with lower energy demands. In addition, this compact liquid chromatography was used as a portable reaction monitoring solution to compare forced degradation kinetics and assess portable liquid chromatography-mass spectrometry capability for the analyses required for pharmaceutical drug product testing.

7.
J Nanobiotechnology ; 21(1): 303, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37641124

RESUMEN

Skeletal muscle disease severity can often progress asymmetrically across muscle groups and heterogeneously within tissues. An example is Duchenne Muscular Dystrophy (DMD) in which lack of dystrophin results in devastating skeletal muscle wasting in some muscles whereas others are spared or undergo hypertrophy. An efficient, non-invasive approach to identify sites of asymmetry and degenerative lesions could enable better patient monitoring and therapeutic targeting of disease. In this study, we utilized a versatile intravenously injectable mesoporous silica nanoparticle (MSNP) based nanocarrier system to explore mechanisms of biodistribution in skeletal muscle of mdx mouse models of DMD including wildtype, dystrophic, and severely dystrophic mice. Moreover, MSNPs could be imaged in live mice and whole muscle tissues enabling investigation of how biodistribution is altered by different types of muscle pathology such as inflammation or fibrosis. We found MSNPs were tenfold more likely to aggregate within select mdx muscles relative to wild type, such as gastrocnemius and quadriceps. This was accompanied by decreased biodistribution in off-target organs. We found the greatest factor affecting preferential delivery was the regenerative state of the dystrophic skeletal muscle with the highest MSNP abundance coinciding with the regions showing the highest level of embryonic myosin staining and intramuscular macrophage uptake. To demonstrate, muscle regeneration regulated MSNP distribution, we experimentally induced regeneration using barium chloride which resulted in a threefold increase of intravenously injected MSNPs to sites of regeneration 7 days after injury. These discoveries provide the first evidence that nanoparticles have selective biodistribution to skeletal muscle in DMD to areas of active regeneration and that nanoparticles could enable diagnostic and selective drug delivery in DMD skeletal muscle.


Asunto(s)
Distrofina , Músculo Esquelético , Animales , Ratones , Distribución Tisular , Ratones Endogámicos mdx , Regeneración
8.
Development ; 150(14)2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37366057

RESUMEN

The earliest skeletal muscle progenitor cells (SMPCs) derived from human pluripotent stem cells (hPSCs) are often identified by factors expressed by a diverse number of progenitors. An early transcriptional checkpoint that defines myogenic commitment could improve hPSC differentiation to skeletal muscle. Analysis of several myogenic factors in human embryos and early hPSC differentiations found SIX1+PAX3+ co-expression was most indictive of myogenesis. Using dCas9-KRAB hPSCs, we demonstrate that early inhibition of SIX1 alone significantly decreased PAX3 expression, reduced PAX7+ SMPCs, and myotubes later in differentiation. Emergence of SIX1+PAX3+ precursors can be improved by manipulating seeding density, monitoring metabolic secretion and altering the concentration of CHIR99021. These modifications resulted in the co-emergence of hPSC-derived sclerotome, cardiac and neural crest that we hypothesized enhanced hPSC myogenic differentiation. Inhibition of non-myogenic lineages modulated PAX3 independent of SIX1. To better understand SIX1 expression, we compared directed differentiations to fetal progenitors and adult satellite cells by RNA-seq. Although SIX1 continued to be expressed across human development, SIX1 co-factor expression was dependent on developmental timing. We provide a resource to enable efficient derivation of skeletal muscle from hPSCs.


Asunto(s)
Células Madre Pluripotentes , Adulto , Humanos , Factor de Transcripción PAX3/genética , Factor de Transcripción PAX3/metabolismo , Células Madre Pluripotentes/metabolismo , Diferenciación Celular/genética , Músculo Esquelético/metabolismo , Desarrollo de Músculos/genética , Factor de Transcripción PAX7/genética , Factor de Transcripción PAX7/metabolismo , Proteínas de Homeodominio/metabolismo
9.
Front Physiol ; 14: 1190524, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37228827

RESUMEN

Duchenne muscular dystrophy (DMD) is caused by an out-of-frame mutation in the DMD gene that results in the absence of a functional dystrophin protein, leading to a devastating progressive lethal muscle-wasting disease. Muscle stem cell-based therapy is a promising avenue for improving muscle regeneration. However, despite the efforts to deliver the optimal cell population to multiple muscles most efforts have failed. Here we describe a detailed optimized method of for the delivery of human skeletal muscle progenitor cells (SMPCs) to multiple hindlimb muscles in healthy, dystrophic and severely dystrophic mouse models. We show that systemic delivery is inefficient and is affected by the microenvironment. We found that significantly less human SMPCs were detected in healthy gastrocnemius muscle cross-sections, compared to both dystrophic and severely dystrophic gastrocnemius muscle. Human SMPCs were found to be detected inside blood vessels distinctly in healthy, dystrophic and severely dystrophic muscles, with prominent clotting identified in severely dystrophic muscles after intra arterial (IA) systemic cell delivery. We propose that muscle microenvironment and the severity of muscular dystrophy to an extent impacts the systemic delivery of SMPCs and that overall systemic stem cell delivery is not currently efficient or safe to be used in cell based therapies for DMD. This work extends our understanding of the severe nature of DMD, which should be taken into account when considering stem cell-based systemic delivery platforms.

10.
Proc Natl Acad Sci U S A ; 120(21): e2218775120, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37186832

RESUMEN

Quantum computing technology may soon deliver revolutionary improvements in algorithmic performance, but it is useful only if computed answers are correct. While hardware-level decoherence errors have garnered significant attention, a less recognized obstacle to correctness is that of human programming errors-"bugs." Techniques familiar to most programmers from the classical domain for avoiding, discovering, and diagnosing bugs do not easily transfer, at scale, to the quantum domain because of its unique characteristics. To address this problem, we have been working to adapt formal methods to quantum programming. With such methods, a programmer writes a mathematical specification alongside the program and semiautomatically proves the program correct with respect to it. The proof's validity is automatically confirmed-certified-by a "proof assistant." Formal methods have successfully yielded high-assurance classical software artifacts, and the underlying technology has produced certified proofs of major mathematical theorems. As a demonstration of the feasibility of applying formal methods to quantum programming, we present a formally certified end-to-end implementation of Shor's prime factorization algorithm, developed as part of a framework for applying the certified approach to general applications. By leveraging our framework, one can significantly reduce the effects of human errors and obtain a high-assurance implementation of large-scale quantum applications in a principled way.

11.
Bioorg Med Chem ; 85: 117273, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37030194

RESUMEN

GPR40 AgoPAMs are highly effective antidiabetic agents that have a dual mechanism of action, stimulating both glucose-dependent insulin and GLP-1 secretion. The early lipophilic, aromatic pyrrolidine and dihydropyrazole GPR40 AgoPAMs from our laboratory were highly efficacious in lowering plasma glucose levels in rodents but possessed off-target activities and triggered rebound hyperglycemia in rats at high doses. A focus on increasing molecular complexity through saturation and chirality in combination with reducing polarity for the pyrrolidine AgoPAM chemotype resulted in the discovery of compound 46, which shows significantly reduced off-target activities as well as improved aqueous solubility, rapid absorption, and linear PK. In vivo, compound 46 significantly lowers plasma glucose levels in rats during an oral glucose challenge yet does not demonstrate the reactive hyperglycemia effect at high doses that was observed with earlier GPR40 AgoPAMs.


Asunto(s)
Glucemia , Hiperglucemia , Ratas , Animales , Receptores Acoplados a Proteínas G , Péptido 1 Similar al Glucagón , Hipoglucemiantes/farmacología , Pirrolidinas/farmacología , Pirrolidinas/química , Insulina
12.
NPJ Regen Med ; 8(1): 16, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36922514

RESUMEN

We developed an on-slide decellularization approach to generate acellular extracellular matrix (ECM) myoscaffolds that can be repopulated with various cell types to interrogate cell-ECM interactions. Using this platform, we investigated whether fibrotic ECM scarring affected human skeletal muscle progenitor cell (SMPC) functions that are essential for myoregeneration. SMPCs exhibited robust adhesion, motility, and differentiation on healthy muscle-derived myoscaffolds. All SPMC interactions with fibrotic myoscaffolds from dystrophic muscle were severely blunted including reduced motility rate and migration. Furthermore, SMPCs were unable to remodel laminin dense fibrotic scars within diseased myoscaffolds. Proteomics and structural analysis revealed that excessive collagen deposition alone is not pathological, and can be compensatory, as revealed by overexpression of sarcospan and its associated ECM receptors in dystrophic muscle. Our in vivo data also supported that ECM remodeling is important for SMPC engraftment and that fibrotic scars may represent one barrier to efficient cell therapy.

14.
IEEE Trans Pattern Anal Mach Intell ; 45(2): 1668-1681, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35503825

RESUMEN

Dynamic measurement precision assessment has been achieved for a differential circle measurement application. Differential circle diameter measurement, in image analysis, typically requires fitting a circle model that optimizes for image distortions, defects or occlusions. The differential task occurs when precise measurements of diameter change are required given object size variation with time. An automated system was designed to provide diameter measurements and associated measurement precision of images of a fuel droplet undergoing combustion in zero gravity for the FLEX-2 dataset. An image gradient-based, least-squares boundary point fitting method to a circle or ellipse model is used for diameter measurement. The presence of soot aggregates poses significant challenges for diameter measurements when it occludes part of the droplet boundary. The precision of the diameter measurements depends upon the image quality. Using synthetic image simulations that model the soot behavior, we developed a model based on image quality measures that assesses the measurement precision for each individual diameter measurement. Thus, diameter measurements with precision assessments were made available for follow-up scientific analysis. The algorithm's success rate for measurable runs was 98%. In cases of limited occlusion, a measurement precision of ±0.2 pixels for the FLEX-2 dataset was achieved.

15.
Trends Cell Biol ; 33(2): 112-123, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35934562

RESUMEN

Stem cell niches are composed of dynamic microenvironments that support stem cells over a lifetime. The emerging niche is distinct from the adult because its main role is to support the progenitors that build organ systems in development. Emerging niches mature through distinct stages to form the adult niche and enable proper stem cell support. As a model of emerging niches, this review highlights how differences in the skeletal muscle microenvironment influence emerging versus satellite cell (SC) niche formation in skeletal muscle, which is among the most regenerative tissue systems. We contrast how stem cell niches regulate intrinsic properties between progenitor and stem cells throughout development to adulthood. We describe new applications for generating emerging niches from human pluripotent stem cells (hPSCs) using developmental principles and highlight potential applications for regeneration and therapeutics.


Asunto(s)
Células Madre Pluripotentes , Células Satélite del Músculo Esquelético , Humanos , Diferenciación Celular , Nicho de Células Madre/fisiología , Músculo Esquelético
16.
Ecancermedicalscience ; 17: 1617, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38414948

RESUMEN

Introduction: Cancellations of elective surgery in low-and middle-income countries (LMIC) are common and a major hindrance for patients who are in need of surgical therapeutic modalities. This is especially important in the context of scaling up needed surgical interventions for gynaecological cancer care. There is a knowledge gap in the literature related to cancellation of gynaecologic oncology surgeries in LMIC, where there is enormous need for this specific cancer surgical capacity. We report in an observational descriptive fashion, our experience at the UTH/CDH in Lusaka, Zambia, on the causes of surgical cancellations in gynaecologic oncology. Methods: From January 1, 2021 through June 31, 2023, we retrospectively evaluated the surgical registry for gynaecologic oncology at the UTH/CDH in Lusaka, Zambia to assess the number and causes of surgical cancellations. Results: There were a total of 66 (16.96%) surgical cancellations out of 389 scheduled gynaecologic oncology cases. Lack of available blood and/or low haemoglobin was the most frequent cause of surgical cancellations, 27 cases (40.90%). Conclusion: We highlight in our series that the lack of blood, leading to surgical cancellations was the most frequent impediment related to performing scheduled gynaecologic oncology surgical procedures. As gynaecologic oncology services scale up in LMIC, given the radical nature of surgery and its association with blood loss, it is incumbent on the entire clinical ecosystem to address this issue and to develop mitigating strategies, specific to their respective resource setting.

17.
iScience ; 25(11): 105415, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36388984

RESUMEN

Duchenne muscular dystrophy (DMD) is caused by out-of-frame mutations in the DMD gene resulting in the absence of a functional dystrophin protein, leading to a devastating and progressive lethal muscle-wasting disease. Little is known about cellular heterogeneity as disease severity increases. Advances in single-cell RNA sequencing (scRNA-seq) enabled us to explore skeletal muscle-resident cell populations in healthy, dystrophic, and severely dystrophic mouse models. We found increased frequencies of activated fibroblasts, fibro-adipogenic progenitor cells, and pro-inflammatory macrophages in dystrophic gastrocnemius muscles and an upregulation of extracellular matrix genes on endothelial cells in dystrophic and severely dystrophic muscles. We observed a pronounced risk of clotting, especially in the severely dystrophic mice with increased expression of plasminogen activator inhibitor-1 in endothelial cells, indicating endothelial cell impairment as disease severity increases. This work extends our understanding of the severe nature of DMD which should be considered when developing single or combinatorial approaches for DMD.

18.
Anal Chem ; 94(40): 13795-13803, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36154017

RESUMEN

N-Nitrosamines are strictly regulated in pharmaceutical products due to their carcinogenic nature. Therefore, the ability to rapidly and reliably identify the N-nitroso functionality is urgently needed. Unfortunately, not all ionized N-nitroso compounds produce diagnostic fragment ions and hence tandem mass spectrometry based on collision-activated dissociation (CAD) cannot be used to consistently identify the N-nitroso functionality. Therefore, a more reliable method was developed based on diagnostic functional-group selective ion-molecule reactions in a linear quadrupole ion trap mass spectrometer. 2-Methoxypropene (MOP) was identified as a reagent that reacts with protonated N-nitrosamines in a diagnostic manner by forming an adduct followed by the elimination of 2-propenol (CH3C(OH)═CH2]). From 18 protonated N-nitrosamine model compounds studied, 15 formed the diagnostic product ion. The lack of the diagnostic reaction for three of the N-nitrosamine model compounds was rationalized based on the presence of a pyridine ring that gets preferentially protonated instead of the N-nitroso functionality. These N-nitrosamines can be identified by subjecting a stable adduct formed upon ion-molecule reactions with MOP to CAD. Further, the ability to use ion-molecule reactions followed by CAD to differentiate protonated O-nitroso compounds with a pyridine ring from analogous N-nitrosamines was demonstrated This methodology is considered to be robust for the identification of the N-nitroso functionality in unknown analytes. Lastly, HPLC/MS2 experiments were performed to determine the detection limit for five FDA regulated N-nitrosamines.


Asunto(s)
Nitrosaminas , Espectrometría de Masas en Tándem , Iones/química , Preparaciones Farmacéuticas , Piridinas , Espectrometría de Masas en Tándem/métodos
20.
ACS Med Chem Lett ; 13(4): 734-741, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35450359

RESUMEN

Mutant isocitrate dehydrogenase 1 (IDH1) has been identified as an attractive oncology target for which >70% of grade II and III gliomas and ∼10% of acute myeloid leukemia (AML) harbor somatic IDH1 mutations. These mutations confer a neomorphic gain of function, leading to the production of the oncometabolite (R)-2-hydroxyglutarate (2-HG). We identified and developed a potent, selective, and orally bioavailable brain-penetrant tricyclic diazepine scaffold that inhibits mutant IDH1. During the course of in vitro metabolism studies, GSH-adduct metabolites were observed. The hypothesis for GSH-adduct formation was driven by the electron-rich nature of the tricyclic core. Herein, we describe our efforts to reduce the electron-rich nature of the core. Ultimately, a strategy focused on core modifications to block metabolic hot spots coupled with substitution pattern changes (C8 N → C linked) led to the identification of new tricyclic analogues with minimal GSH-adduct formation across species while maintaining an overall balanced profile.

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