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1.
Nature ; 591(7849): 281-287, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33568815

RESUMO

Skeletal muscle regenerates through the activation of resident stem cells. Termed satellite cells, these normally quiescent cells are induced to proliferate by wound-derived signals1. Identifying the source and nature of these cues has been hampered by an inability to visualize the complex cell interactions that occur within the wound. Here we use muscle injury models in zebrafish to systematically capture the interactions between satellite cells and the innate immune system after injury, in real time, throughout the repair process. This analysis revealed that a specific subset of macrophages 'dwell' within the injury, establishing a transient but obligate niche for stem cell proliferation. Single-cell profiling identified proliferative signals that are secreted by dwelling macrophages, which include the cytokine nicotinamide phosphoribosyltransferase (Nampt, which is also known as visfatin or PBEF in humans). Nampt secretion from the macrophage niche is required for muscle regeneration, acting through the C-C motif chemokine receptor type 5 (Ccr5), which is expressed on muscle stem cells. This analysis shows that in addition to their ability to modulate the immune response, specific macrophage populations also provide a transient stem-cell-activating niche, directly supplying proliferation-inducing cues that govern the repair process that is mediated by muscle stem cells. This study demonstrates that macrophage-derived niche signals for muscle stem cells, such as NAMPT, can be applied as new therapeutic modalities for skeletal muscle injury and disease.


Assuntos
Macrófagos/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/lesões , Mioblastos/citologia , Nicotinamida Fosforribosiltransferase/metabolismo , Nicho de Células-Tronco , Peixe-Zebra/metabolismo , Animais , Proliferação de Células , Modelos Animais de Doenças , Humanos , Macrófagos/citologia , Masculino , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mioblastos/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Fator de Transcrição PAX7/metabolismo , RNA-Seq , Receptores CCR5/genética , Receptores CCR5/metabolismo , Regeneração/fisiologia , Análise de Célula Única , Peixe-Zebra/imunologia
2.
Australas J Dermatol ; 65(3): e30-e33, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38140736

RESUMO

Jacquet erosive dermatitis (JED) is a rare, severe form of napkin dermatitis associated with friction and irritant exposure in the napkin area. The condition typically causes erosions and erythematous punched-out ulcerations. We present two cases of JED in infants associated with the use of a common brand barrier cream Curash. This appeared to present following a change of several active ingredients.


Assuntos
Creme para a Pele , Humanos , Lactente , Dermatite Irritante/etiologia , Dermatite Irritante/patologia , Fricção , Creme para a Pele/efeitos adversos
3.
BMC Med Educ ; 24(1): 287, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486267

RESUMO

BACKGROUND: Veterinary students have historically lacked meaningful experiential learning opportunities in equine medicine. At the same time, there are barriers to accessing veterinary care in Indigenous communities stemming from colonial injustices. In 2018-2019, a partnership was initiated where University of Calgary students began to provide equine veterinary services to Indigenous communities. As the first-documented equine veterinary service-learning initiative in Indigenous communities embedded in a veterinary curriculum, the purpose of the study is to systematically evaluate the program for its potential impact as part of a formative process for improvement. METHODS: Multiple parties in the program were engaged in a convergent, parallel, mixed-methods systematic program evaluation to explore the main program outcomes: (1) equine veterinary care; (2) clinical experiential student education; (3) cultural training of veterinary professionals and students; and (4) education of community members. The hypothesis was that ethical development using the "first, do no harm principle" would lead to benefits including a healthy horse population, a technically and culturally competent veterinary community, and an educated horse clientele. RESULTS: The program had a positive impact on accessibility to veterinary care and self-reported improvement in veterinary and cultural competency. In addition to the hypothesized program outcomes, additional program outcomes and effects were identified, including reciprocal learning and relationship building with the Indigenous community, leading to trust and equity-building. The students learned from both the in-community programming as well as the Indigenous community members they worked with. CONCLUSION: Program evaluation of an equine service-learning initiative in Indigenous communities reveals multiple and profound impacts including improved patient health status, wider scope of veterinary and cultural learning, strengthened relationships, and reciprocal learning with partnering Indigenous communities.


Assuntos
Currículo , Aprendizagem , Humanos , Cavalos , Animais , Avaliação de Programas e Projetos de Saúde , Canadá , Aprendizagem Baseada em Problemas
4.
Vet Radiol Ultrasound ; 63(3): 345-352, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35048458

RESUMO

Abdominal organ displacement is a potentially life-threatening condition in horses. Primary care veterinarians commonly make referral decisions based on a combination of clinical and ultrasonographic findings. However, published studies describing the effects of transducer on identifying abdominal organ locations in horses are currently lacking. The objective of this prospective, methods comparison, pilot study was to compare organ identification using a high-frequency linear (transrectal) transducer and a low-frequency curvilinear (abdominal) transducer for transcutaneous abdominal ultrasonography of healthy horses. Twelve clinically normal adult horses owned by the University of Calgary were enrolled in the study. Abdominal ultrasonography was performed by four practitioners, each randomly assigned to an alternating rotation of transrectal or abdominal transducer and left or right side of a horse. Using a Chi square test or Fisher's exact test, the frequency of identification for each organ was compared between both transducers. There was no significant difference in organ identification on the right side of the abdomen. On the left side, the stomach, liver, and kidney were less likely to be detected with the transrectal transducer. Compared with a low-frequency abdominal transducer, a high-frequency linear transrectal transducer delivers images that allow for organ identification in transcutaneous ultrasonography of the equine abdomen except for the left kidney, left liver, and stomach.


Assuntos
Abdome , Doenças dos Cavalos , Abdome/diagnóstico por imagem , Animais , Cavalos , Incidência , Projetos Piloto , Estudos Prospectivos , Transdutores , Ultrassonografia/métodos , Ultrassonografia/veterinária
5.
J Vet Med Educ ; 48(4): 485-491, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32758091

RESUMO

The Objective Structured Clinical Examination (OSCE) is a valid, reliable assessment of veterinary students' clinical skills that requires significant examiner training and scoring time. This article seeks to investigate the utility of implementing video recording by scoring OSCEs in real-time using live examiners, and afterwards using video examiners from within and outside the learners' home institution. Using checklists, learners (n=33) were assessed by one live examiner and five video examiners on three OSCE stations: suturing, arthrocentesis, and thoracocentesis. When stations were considered collectively, there was no difference between pass/fail outcome between live and video examiners (χ2 = 0.37, p = .55). However, when considered individually, stations (χ2 = 16.64, p < .001) and interaction between station and type of examiner (χ2 = 7.13, p = .03) demonstrated a significant effect on pass/fail outcome. Specifically, learners being assessed on suturing with a video examiner had increased odds of passing the station as compared with their arthrocentesis or thoracocentesis stations. Internal consistency was fair to moderate (0.34-0.45). Inter-rater reliability measures varied but were mostly moderate to strong (0.56-0.82). Video examiners spent longer assessing learners than live raters (mean of 21 min/learner vs. 13 min/learner). Station-specific differences among video examiners may be due to intermittent visibility issues during video capture. Overall, video recording learner performances appears reliable and feasible, although there were time, cost, and technical issues that may limit its routine use.


Assuntos
Educação em Veterinária , Avaliação Educacional , Animais , Competência Clínica , Estudos de Viabilidade , Reprodutibilidade dos Testes , Gravação em Vídeo
6.
Clin Sci (Lond) ; 134(20): 2665-2679, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33000862

RESUMO

There is a growing appreciation of the role of lung stem/progenitor cells in the development and perpetuation of chronic lung disease including idiopathic pulmonary fibrosis. Human amniotic epithelial cells (hAECs) were previously shown to improve lung architecture in bleomycin-induced lung injury, with the further suggestion that hAECs obtained from term pregnancies possessed superior anti-fibrotic properties compared with their preterm counterparts. In the present study, we aimed to elucidate the differential effects of hAECs from term and preterm pregnancies on lung stem/progenitor cells involved in the repair. Here we showed that term hAECs were better able to activate bronchioalveolar stem cells (BASCs) and type 2 alveolar epithelial cells (AT2s) compared with preterm hAECs following bleomycin challenge. Further, we observed that term hAECs restored TGIF1 and TGFß2 expression levels, while increasing c-MYC expression despite an absence of significant changes to Wnt/ß-catenin signaling. In vitro, term hAECs increased the average size and numbers of BASC and AT2 colonies. The gene expression levels of Wnt ligands were higher in term hAECs, and the expression levels of BMP4, CCND1 and CDC42 were only increased in the BASC and AT2 organoids co-cultured with hAECs from term pregnancies but not preterm pregnancies. In conclusion, term hAECs were more efficient at activating the BASC niche compared with preterm hAECs. The impact of gestational age and/or complications leading to preterm delivery should be considered when applying hAECs and other gestational tissue-derived stem and stem-like cells therapeutically.


Assuntos
Âmnio/citologia , Células Epiteliais/citologia , Pulmão/fisiologia , Nascimento Prematuro/patologia , Regeneração , Células Epiteliais Alveolares/citologia , Animais , Bleomicina , Feminino , Imunofluorescência , Regulação da Expressão Gênica , Via de Sinalização Hippo , Humanos , Ligantes , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Organoides/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Células-Tronco/citologia , Transcrição Gênica , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
7.
Reproduction ; 157(1): 43-52, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30392200

RESUMO

Perivascular mesenchymal stem/stromal cells can be isolated from the human endometrium using the surface marker SUSD2 and are being investigated for use in tissue repair. Mesenchymal stem/stromal cells from other tissues modulate T cell responses via mechanisms including interleukin-10, prostaglandin E2, TGF-ß1 and regulatory T cells. Animal studies demonstrate that endometrial mesenchymal stem/stromal cells can also modify immune responses to implanted mesh, but the mechanism/s they employ have not been explored. We examined the immunomodulatory properties of human endometrial mesenchymal stem/stromal cells on lymphocyte proliferation using mouse splenocyte cultures. Endometrial mesenchymal stem/stromal cells inhibited mitogen-induced lymphocyte proliferation in vitro in a dose-dependent manner. Inhibition of lymphocyte proliferation was not affected by blocking the mouse interleukin-10 receptor or inhibiting prostaglandin production. Endometrial mesenchymal stem/stromal cells continued to restrain lymphocyte proliferation in the presence of an inhibitor of TGF-ß receptors, despite a reduction in regulatory T cells. Thus, the in vitro inhibition of mitogen-induced lymphocyte proliferation by endometrial mesenchymal stem/stromal cells occurs by a mechanism distinct from the interleukin-10, prostaglandin E2, TGF-ß1 and regulatory T cell-mediated mechanisms employed by MSC from other tissues. eMSCs were shown to produce interleukin-17A and Dickkopf-1 which may contribute to their immunomodulatory properties. In contrast to MSC from other sources, systemic administration of endometrial mesenchymal stem/stromal cells did not inhibit swelling in a T cell-mediated model of skin inflammation. We conclude that, while endometrial mesenchymal stem/stromal cells can modify immune responses, their immunomodulatory repertoire may not be sufficient to restrain some T cell-mediated inflammatory events.


Assuntos
Proliferação de Células , Endométrio/citologia , Células-Tronco Mesenquimais/fisiologia , Linfócitos T/fisiologia , Animais , Comunicação Celular/fisiologia , Células Cultivadas , Endométrio/imunologia , Endométrio/metabolismo , Feminino , Humanos , Glicoproteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/fisiologia
8.
Dermatology ; 235(1): 19-34, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30332666

RESUMO

Melanocytic naevi are common melanocytic proliferations that may simulate the appearance of cutaneous melanoma. Naevi commonly harbour somatic mutations implicated in melanomagenesis but in most cases lack the necessary genomic alterations required for melanoma development. While the mitogen-activated protein kinase pathway and ultraviolet radiation strongly contribute to naevogenesis, the somatic mutational landscape of dermoscopic naevus subsets distinguishes some of the molecular hallmarks of naevi in relation to melanoma. We herein discuss the classification of naevi and theories of naevogenesis and review the current literature on the somatic alterations in naevi and melanoma. This review focusses on the clinical-dermoscopic-pathological and genomic correlation of naevi that shapes the current understanding of naevi.


Assuntos
Dermoscopia , Melanoma/genética , Melanoma/patologia , Nevo Pigmentado/genética , Nevo Pigmentado/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Humanos , Melanoma/diagnóstico , Mutação , Nevo Pigmentado/classificação , Nevo Pigmentado/diagnóstico , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/diagnóstico
9.
Australas J Dermatol ; 59(3): e175-e182, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28240347

RESUMO

BACKGROUND/OBJECTIVES: Melanoma apps are smartphone applications that assess risk of pigmented lesions using a smartphone camera and underlying algorithm. We aimed to assess the capability of melanoma smartphone applications (apps) in making clinical decisions about risk, compared with lesion assessment by specialist trained dermatologists. METHODS: A prospective study of 3 melanoma apps was conducted between 2015 and 2016, recruiting 30 patients with 57 pigmented lesions. Risk categories assigned by the apps were compared with the clinical decisions of two consultant dermatologists classifying lesions as 'suspicious' or 'benign'. RESULTS: Of the 42 lesions deemed clinically suspicious to a dermatologist, from 9 to 26 were classified as suspicious by the apps; of the 15 clinically benign lesions 3 to 15 were correctly classified as benign by the apps. The apps' sensitivity and specificity ranged from 21 to 72% and 27 to 100.0%, respectively, when compared with the specialists' decisions. Two apps were unable to analyse 14 and 18% of lesions submitted, respectively. Interrater agreement between dermatologists and apps was poor (κ = -0.01 SE = 0.16; P = 0.97) to slight (κ = 0.16 SE = 0.09; P = 0.12). CONCLUSIONS: None of the melanoma apps tested had high enough agreement with the dermatologist's clinical opinion to be considered to provide additional benefit to patients in assessing their skin for high-risk pigmented lesions. The low sensitivity in detecting lesions that are suspicious to a trained specialist may mean false reassurance is being given to patients. Development of highly sensitive and specific melanoma apps remains a work in progress.


Assuntos
Dermatologia/métodos , Interpretação de Imagem Assistida por Computador , Melanoma/diagnóstico por imagem , Aplicativos Móveis , Neoplasias Cutâneas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Melanoma/classificação , Pessoa de Meia-Idade , Variações Dependentes do Observador , Fotografação , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade , Neoplasias Cutâneas/classificação , Smartphone
10.
Vet Clin North Am Small Anim Pract ; 54(5): 813-824, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39003178

RESUMO

Implicit biases are those we are unwilling to admit, yet they influence our behavior in ways that impact our experience in the workplace. Literature demonstrates that implicit bias influences career choice and limits success within a chosen career. Discrimination in the veterinary workplace is pervasive and has a negative impact that is responsible for financial loss. It can also influence client communication, patient-care, and be inadvertently perpetuated by well-meaning community clinics. Strategies can be employed to acknowledge implicit bias and to foster behavioral change, which results in a healthier workplace and improved client and patient-care.


Assuntos
Médicos Veterinários , Medicina Veterinária , Médicos Veterinários/psicologia , Humanos , Animais , Escolha da Profissão , Preconceito , Viés
11.
J Am Vet Med Assoc ; 262(1): 1-5, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103385

RESUMO

OBJECTIVE: To investigate pseudohyperkalemia occurring in horses experiencing rhabdomyolysis when serum chemistry profiles are run on an VetScan VS2 analyzer (Abaxis). ANIMALS: 18 horses with rhabdomyolysis (creatine kinase [CK] > 1,000 U/L). METHODS: In 3 horses with serum CK activities > 5,800 U/L and persistent serum potassium concentrations of > 8.5 mmol/L (VetScan VS2), potassium concentrations were reevaluated with either i-STAT Alinity Base Station (Abbott), Catalyst (Idexx), or Cobas c501 (Roche) ion-specific analyzers. Paired serum samples from 15 additional horses (median serum CK activity, 7,601 U/L; range, 1,134 to 192,447 U/L) were analyzed on both VetScan VS2 and Cobas c501 machines. Serum potassium concentrations were compared between the VetScan VS2 and ion-specific analyzers by Bland-Altman and Wilcoxon ranked tests and correlated to log10 CK activity via Pearson correlation. RESULTS: Serum potassium concentrations were significantly higher on the VetScan VS2 (6.7 ± 1.6 mmol/L) versus the ion-specific analyzers (4.0 ± 1.1 mmol/L; P < .0001), with high bias shown in Bland-Altman analysis (43.1 ± 27.9). Potassium concentrations positively correlated with log10 CK activity with the VetScan VS2 (R2 = 0.51; P = .003) but not the Cobas (R2 = 0.09; P = .3) analyzer. CLINICAL RELEVANCE: An alternate analyzer to the VetScan VS2 should be used to evaluate serum potassium concentrations in horses with rhabdomyolysis because the VetScan VS2 methodology uses lactate dehydrogenase, which increases in serum with rhabdomyolysis and falsely elevates potassium concentrations.


Assuntos
Doenças dos Cavalos , Rabdomiólise , Animais , Cavalos , Potássio , Rabdomiólise/veterinária
12.
Nat Commun ; 15(1): 6480, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090108

RESUMO

Regulatory T cells (Tregs) are key immune regulators that have shown promise in enhancing cardiac repair post-MI, although the mechanisms remain elusive. Here, we show that rapidly increasing Treg number in the circulation post-MI via systemic administration of exogenous Tregs improves cardiac function in male mice, by limiting cardiomyocyte death and reducing fibrosis. Mechanistically, exogenous Tregs quickly home to the infarcted heart and adopt an injury-specific transcriptome that mediates repair by modulating monocytes/macrophages. Specially, Tregs lead to a reduction in pro-inflammatory Ly6CHi CCR2+ monocytes/macrophages accompanied by a rapid shift of macrophages towards a pro-repair phenotype. Additionally, exogenous Treg-derived factors, including nidogen-1 and IL-10, along with a decrease in cardiac CD8+ T cell number, mediate the reduction of the pro-inflammatory monocyte/macrophage subset in the heart. Supporting the pivotal role of IL-10, exogenous Tregs knocked out for IL-10 lose their pro-repair capabilities. Together, this study highlights the beneficial use of a Treg-based therapeutic approach for cardiac repair with important mechanistic insights that could facilitate the development of novel immunotherapies for MI.


Assuntos
Interleucina-10 , Macrófagos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Linfócitos T Reguladores , Animais , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Linfócitos T Reguladores/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Interleucina-10/metabolismo , Interleucina-10/genética , Fenótipo , Miocárdio/patologia , Miocárdio/imunologia , Miocárdio/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/imunologia , Fibrose , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Camundongos Knockout
13.
Nat Commun ; 15(1): 7863, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251592

RESUMO

Regulatory T cells (Tregs) are crucial immune cells for tissue repair and regeneration. However, their potential as a cell-based regenerative therapy is not yet fully understood. Here, we show that local delivery of exogenous Tregs into injured mouse bone, muscle, and skin greatly enhances tissue healing. Mechanistically, exogenous Tregs rapidly adopt an injury-specific phenotype in response to the damaged tissue microenvironment, upregulating genes involved in immunomodulation and tissue healing. We demonstrate that exogenous Tregs exert their regenerative effect by directly and indirectly modulating monocytes/macrophages (Mo/MΦ) in injured tissues, promoting their switch to an anti-inflammatory and pro-healing state via factors such as interleukin (IL)-10. Validating the key role of IL-10 in exogenous Treg-mediated repair and regeneration, the pro-healing capacity of these cells is lost when Il10 is knocked out. Additionally, exogenous Tregs reduce neutrophil and cytotoxic T cell accumulation and IFN-γ production in damaged tissues, further dampening the pro-inflammatory Mo/MΦ phenotype. Highlighting the potential of this approach, we demonstrate that allogeneic and human Tregs also promote tissue healing. Together, this study establishes exogenous Tregs as a possible universal cell-based therapy for regenerative medicine and provides key mechanistic insights that could be harnessed to develop immune cell-based therapies to enhance tissue healing.


Assuntos
Interleucina-10 , Macrófagos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores , Cicatrização , Animais , Linfócitos T Reguladores/imunologia , Cicatrização/imunologia , Interleucina-10/metabolismo , Interleucina-10/genética , Humanos , Camundongos , Macrófagos/imunologia , Masculino , Monócitos/imunologia , Pele/imunologia , Interferon gama/metabolismo , Interferon gama/imunologia , Feminino
14.
Front Vet Sci ; 10: 1307938, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239746

RESUMO

Abdominal ultrasonography is valuable in the diagnosis of equine colic. Fast localized abdominal sonography of horses (FLASH) enables practitioners with limited experience to perform ultrasonography in emergency settings. However, many practitioners only possess rectal format linear array transducers (RFLT). The hypotheses are: (a) A low frequency curvilinear transducer (LFCT) and RFLT will detect free abdominal fluid and abnormal small intestinal loops with similar frequency during FLASH, and (b) there will be a difference between the transducers for detection of gastric abnormalities and nephrosplenic entrapment. The objective is to compare transcutaneous abdominal ultrasonographic detection of abnormalities in horses presenting with colic using a LFCT and RFLT. Twenty-four horses requiring FLASH for investigation of colic were enrolled. Horses that were too painful to undergo transcutaneous abdominal ultrasonographic examination were excluded. A single investigator performed FLASH on all horses using a RFLT, while one of three other clinicians simultaneously performed FLASH using a LFCT. Comparison of abnormal findings between the two transducers was performed using Chi square, Fisher's exact or Wilcoxon tests. The incidence of identification of abnormal findings was similar between the two transducers for all comparisons except the visibility of the left kidney and stomach (kidney LFCT 81.25% vs. RFLT 22.92%, stomach LFCT 87.5% vs. RFLT 62.5%). While there are limitations to using a RFLT to identify nephrosplenic entrapment of the colon and detection of the stomach, it reliably detects other common abnormalities, including peritoneal effusion, lesions of the small intestine, and changes to the wall of the large colon and cecum.

15.
Acta Biomater ; 168: 144-158, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37422008

RESUMO

Mesenchymal stromal cells (MSCs) have significant therapeutic potential due to their ability to differentiate into musculoskeletal lineages suitable for tissue-engineering, as well as the immunomodulatory and pro-regenerative effects of the paracrine factors that these cells secrete. Cues from the extracellular environment, including physical stimuli such as substrate stiffness, are strong drivers of MSC differentiation, but their effects upon MSC paracrine activity are not well understood. This study, therefore sought to determine the impact of substrate stiffness on the paracrine activity of MSCs, analysing both effects on MSC fate and their effect on T-cell and macrophage activity and angiogenesis. The data show that conditioned medium (CM) from MSCs cultured on 0.2 kPa (soft) and 100 kPa (stiff) polyacrylamide hydrogels have differing effects on MSC proliferation and differentiation, with stiff CM promoting proliferation whilst soft CM promoted differentiation. There were also differences in the effects upon macrophage phagocytosis and angiogenesis, with the most beneficial effects from soft CM. Analysis of the media composition identified differences in the levels of proteins including IL-6, OPG, and TIMP-2. Using recombinant proteins and blocking antibodies, we confirmed a role for OPG in modulating MSC proliferation with a complex combination of factors involved in the regulation of MSC differentiation. Together the data confirm that the physical microenvironment has an important influence on the MSC secretome and that this can alter the differentiation and regenerative potential of the cells. These findings can be used to tailor the culture environment for manufacturing potent MSCs for specific clinical applications or to inform the design of biomaterials that enable the retention of MSC activity after delivery into the body. STATEMENT OF SIGNIFICANCE: • MSCs cultured on 100 kPa matrices produce a secretome that boosts MSC proliferation • MSCs cultured on 0.2 kPa matrices produce a secretome that promotes MSC osteogenesis and adipogenesis, as well as angiogenesis and macrophage phagocytosis • IL-6 secretion is elevated in MSCs on 0.2 kPa substrates • OPG, TIMP-2, MCP-1, and sTNFR1 secretion are elevated in MSCs on 100 kPa substrates.


Assuntos
Transplante de Células-Tronco Mesenquimais , Inibidor Tecidual de Metaloproteinase-2 , Inibidor Tecidual de Metaloproteinase-2/farmacologia , Interleucina-6 , Diferenciação Celular , Engenharia Tecidual , Meios de Cultivo Condicionados/farmacologia
16.
J Clin Oncol ; 41(27): 4406-4415, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37478391

RESUMO

PURPOSE: Bladder-sparing trimodal therapy (TMT) is an alternative to radical cystectomy (RC) according to international guidelines. However, there are limited data to guide management of nonmetastatic clinically node-positive bladder cancer (cN+ M0 BCa). We performed a multicenter retrospective analysis of survival outcomes in node-positive patients to inform practice. METHODS: Data from patients diagnosed with cN+ M0 BCa were collected from participating UK Oncology centers offering both TMT and RC. Overall survival (OS) and progression-free survival (PFS) outcomes were collected with details of treatment and clinical factors. RESULTS: A total of 287 patients with cN+ M0 BCa were included in the survival analysis. Median OS across all patients was 1.55 years (95% CI, 1.35 to 1.82 years). Receiving radical treatments was associated with improved OS (hazard ratio [HR], 0.32; 95% CI, 0.23 to 0.44; P < .001) compared with receiving palliative treatment. Radically treated patients (n = 163) received RC (n = 76) or radical dose radiotherapy (RT, n = 87); choice of radical treatment showed no association with OS (HR, 0.94; 95% CI, 0.63 to 1.41; P = .76) or PFS (HR, 0.74; 95% CI, 0.50 to 1.08; P = .12) on multivariable analysis. CONCLUSION: Patient cohorts with cN+ M0 BCa had equivalent survival outcomes whether treated with surgery or radical RT. Given the known morbidities of RC-in a patient group with poor survival-this study confirms that bladder-sparing TMT treatment should be a treatment option available to all patients with cN+ M0 BCa.


Assuntos
Neoplasias da Bexiga Urinária , Bexiga Urinária , Humanos , Cistectomia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/cirurgia
17.
J Invest Dermatol ; 142(7): 1893-1902.e7, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34871578

RESUMO

Acquired melanocytic nevi grow and persist in a stable form into adulthood. Using genome-wide methylation profiling, we evaluated 32 histopathologically and dermoscopically characterized nevi to identify the key epigenetic regulatory mechanisms involved in nevogenesis. Benign (69% globular and 31% nonspecific dermoscopic pattern) and dysplastic (95% reticular/nonspecific dermoscopic pattern) nevi were dissimilar, with only two shared differentially methylated loci. Benign nevi showed an increase in both genome-scale methylation and methylation of Alu/LINE-1 retrotransposable elements, a marker of genomic stability, as well as global methylation. In contrast, dysplastic nevi showed evidence for genomic instability through the hypomethylation of Alu/LINE-1 (Alu: P = 0.00019; LINE-1: P = 0.000035). Using dermoscopic classifications, reticular/nonspecific patterned nevi had 59,572 5'-C-phosphate-G-3' differentially methylated loci (Q < 0.05), whereas globular nevi had no significant differentially methylated loci. In reticular/nonspecific patterned nevi, the tumor suppressor PTEN had the greatest proportion of hypermethylated 5'-C-phosphate-G-3' loci in its promoter region than all other assayed gene promoters. The relative activity of reticular/nonspecific nevi was evidenced by 50,720 hypomethylated loci being enriched for accessible chromatin and 8,852 hypermethylated loci strongly enriched, for example, marks of active gene promoters, which suggests that gain of DNA methylation observed in these nevus types plays a role in gene regulation.


Assuntos
Nevo de Células Epitelioides e Fusiformes , Nevo Pigmentado , Nevo , Neoplasias Cutâneas , Adulto , Metilação de DNA/genética , Instabilidade Genômica/genética , Humanos , Nevo/genética , Nevo de Células Epitelioides e Fusiformes/genética , Nevo Pigmentado/genética , Nevo Pigmentado/patologia , Fosfatos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
18.
J Am Coll Emerg Physicians Open ; 2(2): e12393, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33718926

RESUMO

OBJECTIVES: Currently, there are no guidelines to help triage nurses identify high-risk emergency department chest pain patients. Patient self-reporting of Emergency Department Assessment of Chest Pain Score (EDACS) could facilitate more reliable triage compared to nursing gestalt, but this novel concept is untested. This study hypothesizes that because EDACS requires minimal clinical gestalt to derive, self-reported EDACS (S-EDACS) at triage is likely to correlate well with traditional physician-reported EDACS (P-EDACS) and have potential application as a triage tool. METHODS: This single-center pilot prospective cohort study analyzed 60 patients who completed a self-reported questionnaire upon triage to determine their S-EDACS. This was matched against P-EDACS, derived from an identical questionnaire completed by the blinded treating physician. Secondary endpoint of major adverse cardiovascular events (MACE) within 30 days (all-cause mortality, myocardial infarction, coronary revascularization) was assessed by 2 blinded emergency physicians who independently reviewed the electronic medical records. S/P-EDACS also were benchmarked against nursing gestalt (based on triage to low/high-acuity areas) and emergency physician gestalt (disposition and admitting/discharge diagnoses). RESULTS: There was perfect agreement between S/P-EDACS in this study (K = 1.00). Fifteen patients (25.0%) had minor discordances in their absolute S/P-EDACS that did not affect risk stratification. Of these, 11/15 (73.3%) had higher S-EDACS, suggesting S-EDACS is more likely to safely overcall MACE risk. S-EDACS outperformed nursing gestalt, triaging a greater proportion of patients (71.7% vs 35.0%) as low risk without compromising patient safety, and demonstrated similar accuracy as emergency physician gestalt. CONCLUSION: S-EDACS strongly correlates with P-EDACS with perfect agreement and has potential to be used as a triage tool.

19.
Cancers (Basel) ; 13(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557011

RESUMO

Paediatric gliomas categorised as low- or high-grade vary markedly from their adult counterparts, and denoted as the second most prevalent childhood cancers after leukaemia. As compared to adult gliomas, the studies of diagnostic and prognostic biomarkers, as well as the development of therapy in paediatric gliomas, are still in their infancy. A body of evidence demonstrates that B-Raf Proto-Oncogene or V-Raf Murine Sarcoma Viral Oncogene Homolog B (BRAF) and histone H3 mutations are valuable biomarkers for paediatric low-grade gliomas (pLGGs) and high-grade gliomas (pHGGs). Various diagnostic methods involving fluorescence in situ hybridisation, whole-genomic sequencing, PCR, next-generation sequencing and NanoString are currently used for detecting BRAF and histone H3 mutations. Additionally, liquid biopsies are gaining popularity as an alternative to tumour materials in detecting these biomarkers, but still, they cannot fully replace solid biopsies due to several limitations. Although histone H3 mutations are reliable prognosis biomarkers in pHGGs, children with these mutations have a dismal prognosis. Conversely, the role of BRAF alterations as prognostic biomarkers in pLGGs is still in doubt due to contradictory findings. The BRAF V600E mutation is seen in the majority of pLGGs (as seen in pleomorphic xanthoastrocytoma and gangliomas). By contrast, the H3K27M mutation is found in the majority of paediatric diffuse intrinsic pontine glioma and other midline gliomas in pHGGs. pLGG patients with a BRAF V600E mutation often have a lower progression-free survival rate in comparison to wild-type pLGGs when treated with conventional therapies. BRAF inhibitors (Dabrafenib and Vemurafenib), however, show higher overall survival and tumour response in BRAF V600E mutated pLGGs than conventional therapies in some studies. To date, targeted therapy and precision medicine are promising avenues for paediatric gliomas with BRAF V600E and diffuse intrinsic pontine glioma with the H3K27M mutations. Given these shortcomings in the current treatments of paediatric gliomas, there is a dire need for novel therapies that yield a better therapeutic response. The present review discusses the diagnostic tools and the perspective of liquid biopsies in the detection of BRAF V600E and H3K27M mutations. An in-depth understanding of these biomarkers and the therapeutics associated with the respective challenges will bridge the gap between paediatric glioma patients and the development of effective therapies.

20.
Commun Biol ; 4(1): 422, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772102

RESUMO

Chronic wounds are a major clinical problem where wound closure is prevented by pathologic factors, including immune dysregulation. To design efficient immunotherapies, an understanding of the key molecular pathways by which immunity impairs wound healing is needed. Interleukin-1 (IL-1) plays a central role in regulating the immune response to tissue injury through IL-1 receptor (IL-1R1). Generating a knockout mouse model, we demonstrate that the IL-1-IL-1R1 axis delays wound closure in diabetic conditions. We used a protein engineering approach to deliver IL-1 receptor antagonist (IL-1Ra) in a localised and sustained manner through binding extracellular matrix components. We demonstrate that matrix-binding IL-1Ra improves wound healing in diabetic mice by re-establishing a pro-healing microenvironment characterised by lower levels of pro-inflammatory cells, cytokines and senescent fibroblasts, and higher levels of anti-inflammatory cytokines and growth factors. Engineered IL-1Ra has translational potential for chronic wounds and other inflammatory conditions where IL-1R1 signalling should be dampened.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Proteína Antagonista do Receptor de Interleucina 1/genética , Cicatrização/fisiologia , Animais , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Masculino , Camundongos , Camundongos Knockout
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