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1.
JCO Oncol Pract ; 20(5): 688-698, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38354324

RESUMEN

PURPOSE: Little data exist regarding approaches to support oncology professionals who deliver cancer care for underserved populations. In response, ASCO developed the Serving the Underserved Task Force to learn from and support oncology professionals serving underserved populations. METHODS: The Task Force developed a 28-question survey to assess oncology professionals' experiences and strategies to support their work caring for underserved populations. The survey was deployed via an online link to 600 oncology professionals and assessed respondent and patient demographic characteristics, clinic-based processes to coordinate health-related social services, and strategies for professional society support and engagement. We used chi-square tests to evaluate whether there were associations between percent full-time equivalent (FTE) effort serving underserved populations (<50% FTE v ≥50% FTE) with responses. RESULTS: Of 462 respondents who completed the survey (77% response rate), 79 (17.1%) were Asian; 30 (6.5%) Black; 43 (9.3%) Hispanic or Latino/Latina; and 277 (60%) White. The majority (n = 366, 79.2%) had a medical doctor degree (MD). A total of 174 (37.7%) had <25% FTE, 151 (32.7%) had 25%-50% FTE, and 121 (26.2%) had ≥50% FTE effort serving underserved populations. Most best guessed patients' sociodemographic characteristics (n = 388; 84%), while 42 (9.2%) used data collected by the clinic. Social workers coordinated most health-related social services. However, in clinical settings with high proportions of underserved patients, there was greater reliance on nonclinical personnel, such as navigators (odds ratio [OR], 2.15 [95% CI, 1.07 to 4.33]) or no individual (OR, 2.55 [95% CI, 1.14 to 5.72]) for addressing mental health needs and greater reliance on physicians or advance practice practitioners (OR, 2.54 [95% CI, 1.11 to 5.81]) or no individual (OR, 1.91 [95% CI, 1.09 to 3.35]) for addressing childcare or eldercare needs compared with social workers. Prioritization of solutions, which did not differ by FTE effort serving underserved populations, included a return-on-investment model to support personnel, integrated health-related social needs screening, and collaboration with the professional society on advocacy and policy. CONCLUSION: The findings highlight crucial strategies that professional societies can implement to support oncology clinicians serving underserved populations with cancer.


Asunto(s)
Oncología Médica , Neoplasias , Humanos , Neoplasias/terapia , Neoplasias/epidemiología , Estados Unidos , Masculino , Femenino , Oncología Médica/métodos , Encuestas y Cuestionarios , Persona de Mediana Edad , Adulto , Comités Consultivos , Área sin Atención Médica , Poblaciones Vulnerables
2.
J Biomed Mater Res B Appl Biomater ; 107(4): 1035-1046, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30199609

RESUMEN

Chronic wounds are a significant health care problem with serious implications for quality of life because they do not properly heal and often require therapeutic intervention. Amniotic membrane allografts have been successfully used as a biologic therapy to promote soft tissue healing; however, the umbilical cord, another placental-derived tissue, has also recently garnered interest because of its unique composition but similar placental tissue origin. The aim of this study was to characterize PURION® PLUS Processed dehydrated human umbilical cord (dHUC) and evaluate the biological properties of this tissue that contribute to healing. This was performed through the characterization of the tissue composition, evaluation of in vitro cellular response to dHUC treatment, and in vivo bioresorption and tissue response in a rat model. It was observed that dHUC contains collagen I, hyaluronic acid, laminin, and fibronectin. Additionally, 461 proteins that consist of growth factors and cytokines, inflammatory modulators, chemokines, proteases and inhibitors, adhesion molecules, signaling receptors, membrane-bound proteins, and other soluble regulators were detected. Cell-based assays demonstrated an increase in adipose-derived stem cell and mesenchymal stem cell proliferation, fibroblast migration and endothelial progenitor cell vessel formation in a dose-dependent manner after dHUC treatment. Lastly, rat subcutaneous implantation demonstrated biocompatibility since dHUC allografts were resorbed without fibrous encapsulation. These findings establish that dHUC possesses biological properties that stimulate cellular responses important for soft tissue healing. © 2018 The Authors. Journal Of Biomedical Materials Research Part B: Applied Biomaterials Published By Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1035-1046, 2019.


Asunto(s)
Vendajes , Ensayo de Materiales , Cordón Umbilical/química , Cicatrización de Heridas , Animales , Proliferación Celular , Desecación , Femenino , Fibroblastos/metabolismo , Humanos , Masculino , Células Madre Mesenquimatosas/metabolismo , Neovascularización Fisiológica , Ratas , Ratas Sprague-Dawley
3.
Bioconjug Chem ; 29(4): 878-884, 2018 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-29341600

RESUMEN

Microtissues containing multiple cell types have been used in both in vitro models and in vivo tissue repair applications. However, to improve throughput, there is a need to develop a platform that supports self-assembly of a large number of 3D microtissues containing multiple cell types in a dynamic suspension system. Thus, the objective of this study was to exploit the binding interaction between the negatively charged glycosaminoglycan, heparin, and a known heparin binding peptide to establish a method that promotes assembly of mesenchymal stem cell (MSC) spheroids into larger aggregates. We characterized heparin binding peptide (HEPpep) and heparin coatings on cell surfaces and determined the specificity of these coatings in promoting assembly of MSC spheroids in dynamic culture. Overall, combining spheroids with both coatings promoted up to 70 ± 11% of spheroids to assemble into multiaggregate structures, as compared to only 10 ± 4% assembly when cells having the heparin coating were cultured with cells coated with a scrambled peptide. These results suggest that this self-assembly method represents an exciting approach that may be applicable for a wide range of applications in which cell aggregation is desired.


Asunto(s)
Agregación Celular , Heparina/metabolismo , Células Madre Mesenquimatosas/citología , Péptidos/metabolismo , Esferoides Celulares/citología , Ingeniería de Tejidos/métodos , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/metabolismo , Esferoides Celulares/metabolismo
4.
Rejuvenation Res ; 20(2): 146-150, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28314379

RESUMEN

Epigenetic variation with age is one of the most important hallmarks of aging. Resetting or repairing the epigenome of aging cells in intact animals may rejuvenate the cells and perhaps the entire organism. In fact, differentiated adult cells, which by definition have undergone some epigenetic changes, are capable of being rejuvenated and reprogrammed to create pluripotent stem cells and viable cloned animals. Apparently, such reprogramming is capable of completely resetting the epigenome. However, attempts to fully reprogram differentiated cells in adult animals have failed in part because reprogramming leads to the formation of teratomas. A preliminary method to partially reprogram adult cells in mature Hutchinson-Gilford Progeria Syndrome (HGPS) mice by transient induction of the Yamanaka factors OSKM (Oct4/Sox2/Klf4/c-Myc) appears to ameliorate aging-like phenotypes in HGPS mice, and promote youthful regenerative capability in middle-aged wild-type individuals exposed to beta cell and muscle cell-specific toxins. However, whatever epigenetic repair is induced by transient reprogramming does not endure and may be due to the induction of key homeostatic regulators instead. Some of the effect of transient reprogramming may result from increased proliferation and enhanced function of adult stem cells. Partial reprogramming may point the way to new antiaging and proregenerative therapeutics. Redifferentiation of cells into their preexisting phenotype with simultaneous epigenomic rejuvenation is an interesting variation that also should be pursued. However, discovery of methods to more precisely repair the epigenome is the most likely avenue to the development of powerful new antiaging agents.


Asunto(s)
Reprogramación Celular/genética , Epigénesis Genética , Rejuvenecimiento/fisiología , Animales , Humanos , Factor 4 Similar a Kruppel , Medicina Regenerativa
5.
Adv Wound Care (New Rochelle) ; 6(2): 43-53, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28224047

RESUMEN

Objective: The use of bioactive extracellular matrix (ECM) grafts such as amniotic membranes is an attractive treatment option for enhancing wound repair. In this study, the concentrations, activity, and distribution of matrix components, growth factors, proteases, and inhibitors were evaluated in PURION® Processed, micronized, dehydrated human amnion/chorion membrane (dHACM; MiMedx Group, Inc.). Approach: ECM components in dHACM tissue were assessed by using immunohistochemical staining, and growth factors, cytokines, proteases, and inhibitors were quantified by using single and multiplex ELISAs. The activities of proteases that were native to the tissue were determined via gelatin zymography and EnzChek® activity assay. Results: dHACM tissue contained the ECM components collagens I and IV, hyaluronic acid, heparin sulfate proteoglycans, fibronectin, and laminin. In addition, numerous growth factors, cytokines, chemokines, proteases, and protease inhibitors that are known to play a role in the wound-healing process were quantified in dHACM. Though matrix metalloproteinases (MMPs) were present in dHACM tissues, inhibitors of MMPs overwhelmingly outnumbered the MMP enzymes by an overall molar ratio of 28:1. Protease activity assays revealed that the MMPs in the tissue existed primarily either in their latent form or complexed with inhibitors. Innovation: This is the first study to characterize components that function in wound healing, including inhibitor and protease content and activity, in micronized dHACM. Conclusion: A variety of matrix components and growth factors, as well as proteases and their inhibitors, were identified in micronized dHACM, providing a better understanding of how micronized dHACM tissue can be used to effectively promote wound repair.

6.
J Biomed Mater Res A ; 104(7): 1817-29, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26990913

RESUMEN

For particular cell-based therapies, it may be required to culture mesenchymal stem cell (MSC) aggregates with growth factors to promote cell proliferation and/or differentiation. Heparin, a negatively charged glycosaminoglycan (GAG) is known to play an important role in sequestration of positively charged growth factors and, when incorporated within cellular aggregates, could be used to promote local availability of growth factors. We have developed a heparin-based cell coating and we believe that the electrostatic interaction between native heparin and the positively charged growth factors will result in (1) higher cell number in response to fibroblast growth factor-2 (FGF-2) and 2) greater chondrogenic differentiation in response to transforming growth factor-ß1 (TGF-ß1), compared to a desulfated heparin coating. Results revealed that in the presence of FGF-2, by day 14, heparin-coated MSC aggregates increased in DNA content 8.5 ± 1.6 fold compared to day 1, which was greater than noncoated and desulfated heparin-coated aggregates. In contrast, when cultured in the presence of TGF-ß1, by day 21, desulfated heparin-coated aggregates upregulated gene expression of collagen II by 86.5 ± 7.5 fold and collagen X by 37.1 ± 4.7 fold, which was higher than that recorded in the noncoated and heparin-coated aggregates. These observations indicate that this coating technology represents a versatile platform to design MSC culture systems with pairings of GAGs and growth factors that can be tailored to overcome specific challenges in scale-up and culture for MSC-based therapeutics. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1817-1829, 2016.


Asunto(s)
Condrogénesis/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Heparina/farmacología , Células Madre Mesenquimatosas/citología , Sulfatos/química , Adulto , Agrecanos/metabolismo , Agregación Celular/efectos de los fármacos , Agregación Celular/genética , Recuento de Células , Forma de la Célula/efectos de los fármacos , Forma de la Célula/genética , Células Cultivadas , Condrogénesis/genética , Colágeno/metabolismo , ADN/metabolismo , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Glicosaminoglicanos/metabolismo , Humanos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Coloración y Etiquetado , Adulto Joven
7.
J Biomed Mater Res B Appl Biomater ; 104(7): 1495-503, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26175122

RESUMEN

Human-derived placental tissues have been shown in randomized clinical trials to be effective for healing chronic wounds, and have also demonstrated the ability to recruit stem cells to the wound site in vitro and in vivo. In this study, PURION(®) Processed dehydrated human amnion/chorion membrane allografts (dHACM, EpiFix(®) , MiMedx Group, Marietta, GA) were evaluated for their ability to alter stem cell activity in vitro. Human bone marrow mesenchymal stem cells (BM-MSCs), adipose derived stem cells (ADSCs), and hematopoietic stem cells (HSCs) were treated with soluble extracts of dHACM tissue, and were evaluated for cellular proliferation, migration, and cytokine secretion. Stem cells were analyzed for cell number by DNA assay after 24 h, closure of an acellular zone using microscopy over 3 days, and soluble cytokine production in the medium of treated stem cells was analyzed after 3 days using a multiplex ELISA array. Treatment with soluble extracts of dHACM tissue stimulated BM-MSCs, ADSCs, and HSCs to proliferate with a significant increase in cell number after 24 h. dHACM treatment accelerated closure of an acellular zone by ADSCs and BM-MSCs after 3 days, compared to basal medium. BM-MSCs, ADSCs, and HSCs also modulated endogenous production of a number of various soluble signals, including regulators of inflammation, mitogenesis, and wound healing. dHACM treatment promoted increased proliferation and migration of ADSCs, BM-MSCs, and HSCs, along with modulation of secreted proteins from those cells. Therefore, dHACM may impact wound healing by amplifying host stem cell populations and modulating their responses in treated wound tissues. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1495-1503, 2016.


Asunto(s)
Amnios/química , Proliferación Celular , Corion/química , Desecación , Células Madre Mesenquimatosas/metabolismo , Cicatrización de Heridas , Humanos , Células Madre Mesenquimatosas/citología
8.
J Tissue Eng Regen Med ; 10(12): 989-999, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-24515660

RESUMEN

Mesenchymal stem cells (MSCs) have been suggested as a potential cell source for tendon/ligament tissue engineering. Extrinsic cues, such as the chemical and physical properties of scaffolds, as well as external forces, play an important role in fibroblastic differentiation of these cells. In this study, we employed a collagen-fibre scaffold that mimics the chemical and fibrous structure and mechanical properties of tendon/ligament, and studied how imparting cyclic tension to these fibrous collagen scaffolds affects tendon/ligament fibroblastic differentiation of MSCs. Human MSCs attached and spread on the surface of the scaffolds, and appeared aligned along the fibres 24 h after seeding. Cyclic tension was then applied to cell-laden scaffolds over a period of 14 days (10% strain, 1 Hz, 3 h on/3 h off). Real time RT-PCR analysis indicated that scleraxis, a transcription factor associated with the tendon fibroblast phenotype, was found to be significantly upregulated only under cyclic tension. Immunohistochemical staining demonstrated that MSCs cultured under cyclic tension after 14 days secreted more extracellular matrix, including collagen I, collagen III and tenascin-C, compared to constructs in static culture, after 14 days in vitro. Our data indicate that cyclic tension can promote fibroblastic differentiation of MSCs in these fibrous collagen-based scaffolds, which may have significant applications in the development of tissue-engineered graft alternatives for tendon and ligament injuries. Copyright © 2014 John Wiley & Sons, Ltd.


Asunto(s)
Diferenciación Celular , Colágeno/química , Fibroblastos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Resistencia a la Tracción , Andamios del Tejido/química , Células Cultivadas , Fibroblastos/citología , Humanos , Células Madre Mesenquimatosas/citología
9.
Crit Rev Oncog ; 20(5-6): 519-35, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27279245

RESUMEN

Every cell type capable of proliferation can be malignantly transformed. However, there appears to be no naturally occurring universal set of genetic mutations capable of converting every cell type to a malignant state. Any specific cell type is generally resistant to transformation by the cancer mutations accumulated by cells of different lineages, presumably due to epigenetic differences. Evidence for this idea derives from experiments in which the developmental fates of cancer cells are altered to reduce malignancy. Reprogramming cancer cells to more primitive developmental states using pluripotency factors (IPS) or somatic nuclear transfer suppresses the malignant phenotype, as does subsequent directed differentiation to mature cells of lineages distinct from the originating cell. Direct transdifferentiation to an alternative cell fate also reduces tumorigenicity. In contrast, after reprogramming, cells induced to redifferentiate toward the original tumor cell type are tumorigenic. In these types of experiments an epigenetic/genetic mismatch often results in suppression of malignancy or cell death. Elucidating the specific transcription and cell signaling network incompatibilities will identify new targets for cancer therapy. Moreover, novel strategies to induce an incompatible transdifferentiated state, in which expression of thousands of genes are altered, will prove useful in controlling malignancies that otherwise easily evolve resistance to single target-based therapeutics. Engineering small molecules, genetic vectors, cytokines, growth factors, targeted extracellular vesicles, and cell fusion will help realize transdifferentiation-based therapeutics for cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Transdiferenciación Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Carcinogénesis , Epigénesis Genética , Genes Relacionados con las Neoplasias , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/fisiopatología , Células Madre Neoplásicas , Transducción de Señal
10.
Insect Biochem Mol Biol ; 33(12): 1167-75, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14599489

RESUMEN

Juvenile hormone (JH) involvement in male reproduction is poorly understood. In Drosophila melanogaster adults, JH deficiency has been shown to result in lowered protein synthesis in male accessory glands. To probe additional roles, we have examined males homozygous for a null allele of Methoprene-tolerant (Met). This gene is involved in the action of JH, possibly at the JH receptor level, and Met(27) null mutants reflect a diminution of JH action. Met(27) males were found to have reduced protein accumulation in male accessory glands and to court and mate wild-type females much less avidly than do either Met(+) or Met(27); Met(+) transgenic males. Exposure of Met(27) males to methoprene partially rescued the courtship deficiency. However, sperm transfer as reflected by fertility of Met(27) fathers was found to be similar to that of Met(+). Taken together with previous work examining the JH-deficient mutant apterous, these results corroborate JH involvement in protein synthesis in the male accessory glands and suggest a role for JH in promoting male mating behavior in these flies.


Asunto(s)
Drosophila melanogaster/fisiología , Hormonas Juveniles/fisiología , Reproducción/fisiología , Alelos , Animales , Cortejo , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Conductos Eyaculadores , Glándulas Exocrinas/metabolismo , Femenino , Fertilidad/efectos de los fármacos , Fertilidad/fisiología , Genotipo , Proteínas de Insectos/aislamiento & purificación , Resistencia a los Insecticidas/genética , Hormonas Juveniles/deficiencia , Hormonas Juveniles/genética , Hormonas Juveniles/metabolismo , Masculino , Metopreno/farmacología , Mutación , Fenotipo , Reproducción/efectos de los fármacos , Conducta Sexual Animal/efectos de los fármacos , Conducta Sexual Animal/fisiología , Transporte Espermático/efectos de los fármacos , Transporte Espermático/fisiología
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