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BACKGROUND: Identifying factors associated with post-disaster youth substance use is a crucial element of developing evidence-based prevention and intervention efforts. Hurricane María struck Puerto Rico in September of 2017 and the wide-spread impact from this disaster, including exposure to trauma, displacement, and disrupted social supports had the potential to negatively impact levels of substance use among youth across the archipelago. However, post-disaster substance use remains under-investigated in this context. The current study sought to identify risk and protective factors associated with substance use among Puerto Rican youth in the aftermath of Hurricane Maria. METHODS: Cross-sectional, secondary data analyses were conducted using school-based survey data collected at all schools in Puerto Rico between February 1 and June 29, 2018 (5-9 months after Hurricane María). Social supports, substance use, and trauma symptoms were assessed. An ordinal regression analysis was conducted to identify student factors associated with greater likelihood of post-disaster substance use. RESULTS: A total of 36,485 participants (50.7% female, grades 7-12), were included in an ordinal regression analysis that compared the likelihood of respondents endorsing high, low, or no substance use after Hurricane María based on reported adult social support, counselor/teacher social support, peer social support, ptsd symptomatology, and gender. Findings showed that, when compared to students that endorsed low or no substance use, those who reported having adult social support demonstrated a 58% reduction in odds (OR = 0.42, 95% CI: 0.34-0.53) of reporting high substance use after Hurricane María, while students who reported having teacher/counselor social support demonstrated a 21% reduction in odds (OR = 0.79, 95% CI: 0.69-0.89) of reporting high substance use. Additionally, those that reported having peer social support demonstrated a 31% increase in odds (OR = 1.31, 95% CI: 1.10 to 1.58) of reporting higher substance use, compared to those that reported low or no substance use. CONCLUSIONS: While social support was generally protective, prevention efforts to build positive family and community connections may be indicated. Evidence-based school screenings of substance use and trauma may help direct intervention to those most at risk for co-occurring issues.
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Tormentas Ciclónicas , Factores Protectores , Apoyo Social , Trastornos Relacionados con Sustancias , Humanos , Estudios Transversales , Femenino , Masculino , Puerto Rico/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Factores de Riesgo , Niño , Desastres , Encuestas y CuestionariosRESUMEN
Youth exposed to natural disasters are at risk of developing trauma-related symptoms as well as engaging in substance use. Although previous research has established associations between disaster-related stressors and substance use in youth, less has focused on how symptoms of posttraumatic stress disorder (PTSD) may underpin this association. The current study used network analysis to identify specific PTSD symptoms associated with substance use following a natural disaster. Participants were 91,732 youths (Grades 3-12) from across Puerto Rico who completed a needs assessment 5-9 months after Hurricane Maria made landfall in September 2017. We examined associations between PTSD symptoms and substance use, identified clusters of symptoms and bridges between them, and explored age- and binary gender-related differences in associations between specific PTSD symptoms and substance use. Analyses identified two symptom communities: (a) arousal and reactivity, negative alterations in cognition and mood, and substance use, and (b) avoidance and intrusion. Broader findings suggested that substance use was most strongly associated with PTSD-related irritability and angry outbursts among youths. Surrounding nodes explained only 4.1% of the variance in substance use, but this was higher among youths who reported not having a supportive adult, R2 = 8.5; friend, R2 = 7.9; or teacher/counselor, R2 = 7.7, in their life. The bridge symptoms of sleep disruption and physiological reactivity were identified as potentially critical intervention targets for disrupting PTSD symptom networks after a natural disaster. Implications for triaged mental health care following natural disasters and directions for future research are discussed.
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Tormentas Ciclónicas , Desastres Naturales , Trastornos por Estrés Postraumático , Trastornos Relacionados con Sustancias , Adolescente , Humanos , Hispánicos o Latinos/psicología , Trastornos por Estrés Postraumático/psicología , Trastornos Relacionados con Sustancias/epidemiología , Puerto Rico , NiñoRESUMEN
Natural killer (NK) cells are innate lymphocytes with cytotoxic activity. Understanding the factors regulating cytotoxicity is crucial for improving NK-cell adoptive therapies. Here, we studied a previously unknown role of p35 (CDK5R1), a coactivator of cyclin-dependent kinase 5 (CDK5) in NK-cell function. p35 expression was thought to be neuronal-specific and the majority of studies are still focused on neuronal cells. Here, we show that CDK5 and p35 are expressed in NK cells and are kinase-active. NK cells from p35 knockout mice were analyzed and showed significantly increased cytotoxicity against murine cancer cells, while they did not show any differences in cell numbers or maturation stages. We confirmed this using human NK cells transduced with p35 short hairpin RNA (shRNA), showing similar increase in cytotoxicity against human cancer cells. Overexpression of p35 in NK cells resulted in moderate decrease in cytotoxicity, while expressing a kinase-dead mutant of CDK5 displayed increased cytotoxicity. Together, these data suggest that p35 negatively regulates NK-cell cytotoxicity. Surprisingly, we found that TGFß, a known negative regulator of NK-cell cytotoxicity, induces p35 expression in NK cells. NK cells cultured with TGFß exhibit reduced cytotoxicity, while NK cells transduced with p35 shRNA or mutant CDK5 expression exhibited partial reversal of this inhibitory effect pointing to an interesting hypothesis that p35 plays an important role in TGFß-mediated NK-cell exhaustion. Significance: This study reports a role for p35 in NK-cell cytotoxicity and this might help to improve NK-cell adoptive therapy.
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Proteínas del Tejido Nervioso , Factor de Crecimiento Transformador beta , Animales , Humanos , Ratones , Células Asesinas Naturales/metabolismo , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Fosfotransferasas/metabolismo , ARN Interferente Pequeño , Factor de Crecimiento Transformador beta/genéticaRESUMEN
Mitophagy plays an important role in maintaining mitochondrial homeostasis by clearing damaged mitochondria. Sphingosine kinase 2 (SK2), a type of sphingosine kinase, is an important metabolic enzyme involved in generating sphingosine-1-phosphate. Its expression level is elevated in many cancers and is associated with poor clinical outcomes. However, the relationship between SK2 and mitochondrial dysfunction remains unclear. We found that the genetic downregulation of SK2 or treatment with ABC294640, a specific inhibitor of SK2, induced mitophagy and apoptosis in multiple myeloma cell lines. We showed that mitophagy correlates with apoptosis induction and likely occurs through the SET/PP2AC/PARK2 pathway, where inhibiting PP2AC activity may rescue this process. Furthermore, we found that PP2AC and PARK2 form a complex, suggesting that they might regulate mitophagy through protein-protein interactions. Our study demonstrates the important role of SK2 in regulating mitophagy and provides new insights into the mechanism of mitophagy in multiple myeloma.
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Mitofagia , Mieloma Múltiple , Humanos , Apoptosis , Mitocondrias/metabolismo , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genéticaRESUMEN
Multiple myeloma (MM) remains an incurable disease and there is an unmet medical need for novel therapeutic drugs that do not share similar mechanisms of action with currently available agents. Sphingosine kinase 2 (SK2) is an innovative molecular target for anticancer therapy. We previously reported that treatment with SK2 inhibitor opaganib inhibited myeloma tumor growth in vitro and in vivo in a mouse xenograft model. In the current study, we performed a phase I study of opaganib in patients with relapsed/refractory multiple myeloma (RRMM). Thirteen patients with RRMM previously treated with immunomodulatory agents and proteasome inhibitors were enrolled and treated with single-agent opaganib at three oral dosing regimens (250 mg BID, 500 mg BID, or 750 mg BID, 28 days as a cycle). Safety and maximal tolerated dose (MTD) were determined. Pharmacokinetics, pharmacodynamics, and correlative studies were also performed. Opaganib was well tolerated up to a dose of 750 mg BID. The most common possibly related adverse event (AE) was decreased neutrophil counts. There were no serious AEs considered to be related to opaganib. MTD was determined as at least 750 mg BID. On an intent-to-treat basis, one patient (7.7%) in the 500 mg BID dose cohort showed a very good partial response, and one other patient (7.7%) achieved stable disease for 3 months. SK2 is an innovative molecular target for antimyeloma therapy. The first-in-class SK2 inhibitor opaganib is generally safe for administration to RRMM patients, and has potential therapeutic activity in these patients. Clinicaltrials.gov: NCT02757326.
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Mieloma Múltiple , Humanos , Animales , Ratones , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Fosfotransferasas (Aceptor de Grupo Alcohol)/uso terapéutico , Inhibidores de Proteasoma/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , DexametasonaRESUMEN
Background: Clinical risk assessment scores, such as IMPEDE VTE, can identify patients with multiple myeloma (MM) at high-risk of venous thromboembolism (VTE). Refinement of these scores, by including 1 or more biomarkers, could improve risk assessment. Objectives: We sought to determine the association between soluble P-selectin (sP-selectin) and D-dimer with VTE in MM. Methods: We identified 545 patients with newly diagnosed MM. Using a nested case-control design, we identified 38 cases of VTE within 6-months of MM treatment and 137 randomly selected controls. Using logistic regression, we examined the association between D-dimer and sP-selectin with VTE. We also analyzed the association after adjusting for IMPEDE VTE. Results: Each 1-point increase in IMPEDE VTE score was associated with a 27% increase in odds of VTE (odds ratio 1.27; 95% CI 1.08-1.51; c-statistic 0.61; 95% CI 0.51-0.71). There was no association between sP-selectin and VTE. Each one increase in natural log of D-dimer was associated with a 44% increase in odds of VTE, so we assigned points (ranging from -2 to +2) to D-dimer values and incorporated them into IMPEDE VTE, forming IMPEDED VTE. There was a 30% increase in odds of VTE per each 1-point increase in IMPEDED VTE (OR 1.30; 95% CI 1.12-1.52; c-statistic 0.65; 95% CI 0.55-0.75). Conclusion: Among patients with newly diagnosed MM starting chemotherapy, D-dimer was associated with increased odds of developing VTE within the subsequent 6-months. The addition of D-dimer to IMPEDE VTE-IMPEDED VTE-could improve prediction of VTE among patients with MM.
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BACKGROUND: Crisis plans for healthcare organisations most often focus on operational needs including staffing, supplies and physical plant needs. Less attention is focused on how leaders can support and encourage individual clinical team members to conduct themselves as professionals during a crisis. METHODS: This qualitative study analysed observations from 79 leaders at 160 hospitals that participate in two national professionalism programmes who shared their observations in focus group discussions about what they believed were the essential elements of leading and addressing professional accountability during a crisis. RESULTS: Analysis of focus group responses identified six leadership practices adopted by healthcare organisations, which were felt to be essential for organisations to navigate the crisis successfully. Unique aspects of maintaining professionalism during each phase of the pandemic were identified and described. CONCLUSIONS: Leaders need a plan to support an organiation's pursuit of professionalism during a crisis. Leaders participating in this study identified practices that should be carefully woven into efforts to support the ongoing safety and quality of the care delivered by healthcare organisations before, during and after a crisis. The lessons learnt from the COVID-19 pandemic may be useful during subsequent crises and challenges that a healthcare organisation might experience.
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COVID-19 , Pandemias , COVID-19/epidemiología , Hospitales , Humanos , Liderazgo , ProfesionalismoRESUMEN
Hazard mitigation plans can support communities' resilience in the context of natural hazards and climate change. The quality of these plans can be evaluated using established indicators; however, research is also needed regarding the perceptions of participants in planning processes, to understand aspects of the planning processes that may not be evident in the plan documents. This study builds on previously reported plan quality scores and survey data, to investigate whether selected collaboration dynamics (principled engagement and capacity for joint action) occurred during counties' hazard planning processes. Semi-structured interviews were conducted with 20 hazard planning professionals who were involved in preparing county-level hazard mitigation plans in Washington State, USA. Findings (for cases with both high- and low-scoring plans) include evidence of collaboration dynamics, although important participants (e.g., members of the local community) were reportedly missing from some planning processes, raising concerns about the extent to which the plans reflect local needs. These results are consistent with previous literature, which has demonstrated that members of the public often view hazard mitigation as inaccessible and disconnected from their daily lives. The paper concludes with recommendations for how practitioners might go about bolstering participation from important participants, potentially leading to higher-quality plans and helping to protect communities from hazards.
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Planificación en Desastres , Desastres Naturales , Cambio Climático , Ambiente , Humanos , WashingtónRESUMEN
Natural killer (NK) cells mediate killing of malignant and virus-infected cells, a property that is explored as a cell therapy approach in the clinic. Various cell intrinsic and extrinsic factors affect NK cell cytotoxic function, and an improved understanding of the mechanism regulating NK cell function is necessary to accomplish better success with NK cell therapeutics. Here, we explored the role of O-GlcNAcylation, a previously unexplored molecular mechanism regulating NK cell function. O-GlcNAcylation is a post-translational modification mediated by O-GlcNAc transferase (OGT) that adds the monosaccharide N-acetylglucosamine to serine and threonine residues on intracellular proteins and O-GlcNAcase (OGA) that removes the sugar. We found that stimulation of NK cells with the cytokines interleukin-2 (IL-2) and IL-15 results in enhanced O-GlcNAcylation of several cellular proteins. Chemical inhibition of O-GlcNAcylation using OSMI-1 was associated with a decreased expression of NK cell receptors (NKG2D, NKG2A, NKp44), cytokines [tumor necrosis factor (TNF)-α, interferon (IFN-γ)], granulysin, soluble Fas ligand, perforin, and granzyme B in NK cells. Importantly, inhibition of O-GlcNAcylation inhibited NK cell cytotoxicity against cancer cells. However, increases in O-GlcNAcylation following OGA inhibition using an OGA inhibitor or shRNA-mediated suppression did not alter NK cell cytotoxicity. Finally, we found that NK cells pretreated with OSMI-1 to inhibit O-GlcNAcylation showed compromised cytotoxic activity against tumor cells in vivo in a lymphoma xenograft mouse model. Overall, this study provides the seminal insight into the role of O-GlcNAcylation in regulating NK cell cytotoxic function.
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Acetilglucosamina , Procesamiento Proteico-Postraduccional , Acetilglucosamina/metabolismo , Animales , Citocinas/metabolismo , Humanos , Células Asesinas Naturales/metabolismo , Ratones , Serina/metabolismoRESUMEN
Mantle cell lymphoma (MCL) is an aggressive form of B cell non-Hodgkin's lymphoma and remains incurable under current treatment modalities. One of the main reasons for treatment failure is the development of drug resistance. Accumulating evidence suggests that B cell activating factor (BAFF) and BAFF receptor (BAFF-R) play an important role in the proliferation and survival of malignant B cells. High serum BAFF levels are often correlated with poor drug response and relapse in MCL patients. Our study shows that BAFF-R is expressed on both MCL patient cells and cell lines. BAFF-R knockdown leads to MCL cell death showing the importance of BAFF-R signaling in MCL survival. Moderate knockdown of BAFF-R in MCL cells did not affect its viability, but sensitized them to cytarabine treatment in vitro and in vivo, with prolonged mice survival. Anti-BAFF-R antibody treatment promoted drug-induced MCL cell death. Conversely, the addition of recombinant BAFF (rhBAFF) to MCL cells protected them from cytarabine-induced apoptosis. We tested the efficacy of a humanized defucosylated ADCC optimized anti-BAFF-R antibody in killing MCL. Our data show both in vitro and in vivo efficacy of this antibody for MCL therapy. To conclude, our data indicate that BAFF/BAFF-R signaling is crucial for survival and involved in drug resistance of MCL. Targeting BAFF-R using BAFF-R antibody might be a promising therapeutical strategy to treat MCL patients resistant to chemotherapy.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Receptor del Factor Activador de Células B , Linfoma de Células del Manto , Animales , Apoptosis , Factor Activador de Células B/genética , Receptor del Factor Activador de Células B/genética , Humanos , Linfoma de Células del Manto/tratamiento farmacológico , Ratones , Recurrencia Local de NeoplasiaRESUMEN
We determined the impact of bone marrow fibrosis (BMF) on the clinical outcomes of newly diagnosed multiple myeloma (NDMM) patients in the current era of myeloma therapy. A total of 393 MM patients were included in the final analysis. The median followup was 83 months (range: 3.9 to 212 months). BMF was noted in 122 (48.2%) evaluable patients. Median progression free survival (PFS) in patients without BMF was 30.2 (95% CI: 24.7-38.0) months, and 21.1 (95% CI: 18.8-27.5) months in patients with BMF present (P = .024). Median overall survival (OS) was 61.2 (95% CI: 51.5-81.2) months in patients without BMF, and 45.1 (95% CI: 38.7-57.0) months in patients with BMF (P = .0048). A subset of 99 patients had their bone marrow biopsies stained for JAK1 and JAK2 by immunohistochemistry. Of these samples 67 (67.7%) patients had detectable JAK2 expression predominantly noted on bone marrow megakaryocytes. JAK2 expression correlated with myeloma disease stage (P = .0071). Our study represents the largest dataset to date examining the association of BMF with prognosis in the era of novel therapies and widespread use of hematopoietic stem cell transplant (HSCT). Our data suggest that MM patients with BMF (particularly those with extensive BMF) have a poorer prognosis even when treated with immunomodulatory agents and proteasome inhibitors.
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Factores Inmunológicos/uso terapéutico , Janus Quinasa 2/análisis , Mieloma Múltiple/tratamiento farmacológico , Mielofibrosis Primaria/complicaciones , Inhibidores de Proteasoma/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Médula Ósea/química , Médula Ósea/patología , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Janus Quinasa 1/análisis , Masculino , Megacariocitos/química , Persona de Mediana Edad , Mieloma Múltiple/metabolismo , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Mielofibrosis Primaria/mortalidad , Pronóstico , Supervivencia sin Progresión , Estudios Retrospectivos , Sindecano-1/análisis , Resultado del TratamientoRESUMEN
PURPOSE: We performed a retrospective chart review on 393 patients with multiple myeloma (MM) to determine the utility of the gamma gap (GG). METHODS: We calculated the difference between a patient's total serum protein and albumin as a point-of-care test for assessing disease status in MM. RESULTS: GG is highly correlated with the level of M-spike, and the change in GG correlates with myeloma treatment response. In addition, fitted linear models were established that allow for the calculation of M-protein level from the GG within hours from blood draw. CONCLUSION: Our study has important implications in the care of MM, particularly in countries/areas with limited resources.
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Mieloma Múltiple , Costo de Enfermedad , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Pruebas en el Punto de Atención , Estudios RetrospectivosRESUMEN
The roles of mitochondrial dysfunction in carcinogenesis remain largely unknown. The effects of PTEN-induced putative kinase 1 (PINK1)-dependent mitophagy on the pathogenesis of multiple myeloma (MM) are determined. The levels of the PINK1-dependent mitophagy markers PINK1 and parkin RBR E3 ubiquitin protein ligase (PARK2) in CD138+ plasma cells are reduced in patients with MM and correlate with clinical outcomes in myeloma patients. Moreover, the induction of PINK1-dependent mitophagy with carbonylcyanide-m-chlorophenylhydrazone (CCCP) or salinomycin, or overexpression of PINK1 leads to inhibition of transwell migration, suppression of myeloma cell homing to calvarium, and decreased osteolytic bone lesions. Furthermore, genetic deletion of pink1 accelerates myeloma development in a spontaneous X-box binding protein-1 spliced isoform (XBP-1s) transgenic myeloma mouse model and in VK*MYC transplantable myeloma recipient mice. Additionally, treatment with salinomycin shows significant antimyeloma activities in vivo in murine myeloma xenograft models. Finally, the effects of PINK1-dependent mitophagy on myeloma pathogenesis are driven by the activation of the Mps one binder kinase activator (MOB1B)-mediated Hippo pathway and the subsequent downregulation of Yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) expression. These data provide direct evidence that PINK1-dependent mitophagy plays a critical role in the pathogenesis of MM and is a potential therapeutic target.
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A cure for multiple myeloma (MM), a malignancy of plasma cells, remains elusive. Nearly all myeloma patients will eventually relapse and develop resistance to currently available treatments. There is an unmet medical need to develop novel and effective therapies that can induce sustained responses. Early phase clinical trials using chimeric antigen receptor (CAR) T cell therapy have shown great promise in the treatment of relapsed and/or refractory MM. In this review article, we provide an overview of the CAR constructs, the gene transfer vector systems, and approaches for T cell activation and expansion. We then summarize the outcomes of several early phase clinical trials of CAR T cell therapy in MM and the novel CAR T targets that are under development. Finally, we explore the potential mechanisms that result in disease relapse after CAR T therapy and propose future directions in CAR T therapy in MM.
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Inmunoterapia Adoptiva/métodos , Mieloma Múltiple/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Receptores Quiméricos de Antígenos/inmunología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Inmunoterapia Adoptiva/tendencias , Mieloma Múltiple/inmunología , Mieloma Múltiple/metabolismo , Recurrencia Local de Neoplasia , Evaluación de Resultado en la Atención de Salud , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores Quiméricos de Antígenos/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
Chondrocytes play an essential role in fracture healing by producing cartilage, which forms an anlage for endochondral ossification that stabilizes the healing fracture callus. More recently it has been appreciated that chondrocytes have the capacity to produce factors that may affect the healing process. We examined the role of chondrocytes in angiogenesis during fracture healing and the role of the transcription factor forkhead box-O 1 (FOXO1), which upregulates wound healing in soft tissue. Closed fractures were induced in experimental mice with lineage-specific FOXO1 deletion by Cre recombinase under the control of a collagen-2α1 promoter element (Col2α1Cre+ FOXO1L/L ) and Cre recombinase negative control littermates containing flanking loxP sites (Col2α1Cre- FOXO1L/L ). Experimental mice had significantly reduced CD31+ new vessel formation. Deletion of FOXO1 in chondrocytes in vivo suppressed the expression of vascular endothelial growth factor-A (VEGFA) at both the protein and mRNA levels. Overexpression of FOXO1 in chondrocytes in vitro increased VEGFA mRNA levels and VEGFA transcriptional activity whereas silencing FOXO1 reduced it. Moreover, FOXO1 interacted directly with the VEGFA promoter and a deacetylated FOXO1 mutant enhanced VEGFA expression whereas an acetylated FOXO1 mutant did not. Lastly, FOXO1 knockdown by siRNA significantly reduced the capacity of chondrocytes to stimulate microvascular endothelial cell tube formation in vitro. The results indicate that chondrocytes play a key role in angiogenesis which is FOXO1 dependent and that FOXO1 in chondrocytes regulates a potent angiogenic factor, VEGFA. These studies provide new insight into fracture healing given the important role of vessel formation in the fracture repair process. © 2018 American Society for Bone and Mineral Research.
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Condrocitos/metabolismo , Proteína Forkhead Box O1/metabolismo , Curación de Fractura , Neovascularización Fisiológica , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Animales , Línea Celular , Colágeno Tipo II/biosíntesis , Colágeno Tipo II/genética , Regulación hacia Abajo , Células Endoteliales/patología , Proteína Forkhead Box O1/genética , Eliminación de Gen , Ratones , Ratones Transgénicos , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/biosíntesis , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
Diabetes increases the likelihood of fracture, interferes with fracture healing and impairs angiogenesis. The latter may be significant due to the critical nature of angiogenesis in fracture healing. Although it is known that diabetes interferes with angiogenesis the mechanisms remain poorly defined. We examined fracture healing in normoglycemic and streptozotocin-induced diabetic mice and quantified the degree of angiogenesis with antibodies to three different vascular markers, CD34, CD31 and Factor VIII. The role of diabetes-enhanced inflammation was investigated by treatment of the TNFα-specific inhibitor, pegsunercept starting 10days after induction of fractures. Diabetes decreased both angiogenesis and VEGFA expression by chondrocytes. The reduced angiogenesis and VEGFA expression in diabetic fractures was rescued by specific inhibition of TNF in vivo. In addition, the TNF inhibitor rescued the negative effect of diabetes on endothelial cell proliferation and endothelial cell apoptosis. The effect of TNFα in vitro was enhanced by high glucose and an advanced glycation endproduct to impair microvascular endothelial cell proliferation and tube formation and to stimulate apoptosis. The effect of TNF, high glucose and an AGE was mediated by the transcription factor FOXO1, which increased expression of p21 and caspase-3. These studies indicate that inflammation plays a major role in diabetes-impaired angiogenesis in endochondral bone formation through its effect on microvascular endothelial cells and FOXO1.
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Diabetes Mellitus Experimental/metabolismo , Curación de Fractura/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Antígenos CD34/sangre , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/inmunología , Diabetes Mellitus Experimental/fisiopatología , Factor VIII/metabolismo , Curación de Fractura/inmunología , Hiperglucemia/sangre , Hiperglucemia/inmunología , Hiperglucemia/metabolismo , Hiperglucemia/fisiopatología , Inflamación/sangre , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/fisiopatología , Masculino , Ratones , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/sangre , Polietilenglicoles/farmacología , Receptores Tipo I de Factores de Necrosis Tumoral/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/sangre , Factor A de Crecimiento Endotelial Vascular/sangreRESUMEN
Forkhead box-O (FOXO) transcription factors have a fundamental role in the development and differentiation of immune cells. FOXO1 and FOXO3 are FOXO members that are structurally similar and bind to the same conserved consensus DNA sequences to induce transcription. FOXO1 has been studied in detail in the activation of dendritic cells (DCs), where it plays an important role through the regulation of target genes such as ICAM-1, CCR7, and the integrin αvß3. FOXO1 is activated by bacteria challenge in DCs and promotes DC bacterial phagocytosis, migration, homing to lymph nodes, DC stimulation of CD4+ T cells and resting B cells, and antibody production. Deletion of FOXO1 in DCs enhances susceptibility to bacteria-induced periodontal disease. FOXO1 and FOXO3 maintain naive T cell quiescence and survival. FOXO1 and FOXO3 enhance the formation of regulatory T cells and inhibit the formation of T-helper 1 (Th1) and Th17 cells. FOXO1 promotes differentiation, proliferation, survival, immunoglobulin gene rearrangement, and class switching in B cells, but FOXO3 has little effect. Both FOXO1 and FOXO3 are important in the maintenance of hematopoietic stem cells by protecting them from oxidative stress. This review examines FOXO1/FOXO3 in the adaptive immune response, key target genes, and FOXO inhibition by the phosphoinositide 3-kinase/AKT pathway.
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Linfocitos B/inmunología , Células Dendríticas/inmunología , Proteína Forkhead Box O1/inmunología , Células Madre Hematopoyéticas/inmunología , Linfocitos T/inmunología , Animales , Humanos , Transducción de Señal/inmunologíaRESUMEN
Soft tissue hemangiomas are commonly encountered lesions, accounting for 7-10 % of all benign soft tissue masses (Mitsionis et al. J Foot Ankle Surg 16(2):27-9, 2010). While the literature describes the great majority of hemangiomas as asymptomatic and discovered only as incidental findings, they do have the potential to induce reactive changes in neighboring structures (Pastushyn et al. Surg Neurol 50(6):535-47, 1998). When these variants occur in close proximity to bone, they may elicit a number of well-documented reactive changes in osseous tissue (Mitsionis et al. J Foot Ankle Surg 16(2):27-9, 2010; DeFilippo et al. Skelet Radiol 25(2):174-7, 1996; Ly et al. AJR Am J Roentgenol 180(6):1695-700, 2003; Sung et al. Skelet Radiol 27(4):205-10, 1998). However, instances of direct extension into bone by soft tissue hemangiomas--that is, infiltration of the mass's vascular components into nearby osseous tissue--are currently undocumented in the literature. In these cases, imaging plays an important role in differentiating hemangiomas from malignant lesions (Mitsionis et al. J Foot Ankle Surg 16(2):27-9, 2010; Sung et al. Skelet Radiol 27(4):205-10, 1998; Pourbagher, Br J Radiol 84(1008):1100-8, 2011). In this article, we present such a case that involved the sacral spine. Imaging revealed a soft tissue mass with direct extension of vascular components into osseous tissue of the adjacent sacral vertebrae. Biopsy and subsequent histopathologic examination led to definitive diagnosis of soft tissue hemangioma. While MRI is widely regarded as the gold standard imaging modality for evaluating hemangiomas, in this report we describe how CT can aid in narrowing the differential diagnosis when one encounters a vascular lesion with adjacent osseous changes. Furthermore, we review the literature as it pertains to the imaging of soft tissue hemangiomas that occur in proximity to osseous tissue, as well as correlate this case to current theories on the pathogenesis of hemangiomas. Radiologists should be aware that benign soft tissue hemangiomas demonstrate a spectrum of imaging findings, including aggressive-appearing changes to adjacent bone.