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1.
Am J Hum Genet ; 110(9): 1590-1599, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37683613

RESUMEN

The island of St Helena played a crucial role in the suppression of the transatlantic slave trade. Strategically located in the middle of the South Atlantic, it served as a staging post for the Royal Navy and reception point for enslaved Africans who had been "liberated" from slave ships intercepted by the British. In total, St Helena received approximately 27,000 liberated Africans between 1840 and 1867. Written sources suggest that the majority of these individuals came from West Central Africa, but their precise origins are unknown. Here, we report the results of ancient DNA analyses that we conducted as part of a wider effort to commemorate St Helena's liberated Africans and to restore knowledge of their lives and experiences. We generated partial genomes (0.1-0.5×) for 20 individuals whose remains had been recovered during archaeological excavations on the island. We compared their genomes with genotype data for over 3,000 present-day individuals from 90 populations across sub-Saharan Africa and conclude that the individuals most likely originated from different source populations within the general area between northern Angola and Gabon. We also find that the majority (17/20) of the individuals were male, supporting a well-documented sex bias in the latter phase of the transatlantic slave trade. The study expands our understanding of St Helena's liberated African community and illustrates how ancient DNA analyses can be used to investigate the origins and identities of individuals whose lives were bound up in the story of slavery and its abolition.


Asunto(s)
Pueblo Africano , Personas Esclavizadas , Humanos , Femenino , Masculino , ADN Antiguo , Población Negra/genética , Genotipo
3.
FASEB J ; 38(7): e23602, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38581236

RESUMEN

Neurotensin (NTS) is a 13-amino acid peptide which is highly expressed in the mammalian ovary in response to the luteinizing hormone surge. Antibody neutralization of NTS in the ovulatory follicle of the cynomolgus macaque impairs ovulation and induces follicular vascular dysregulation, with excessive pooling of red blood cells in the follicle antrum. We hypothesize that NTS is an essential intrafollicular regulator of vascular permeability. In the present study, follicle injection of the NTS receptor antagonist SR142948 also resulted in vascular dysregulation. To measure vascular permeability changes in vitro, primary macaque ovarian microvascular endothelial cells (mOMECs) were enriched from follicle aspirates and studied in vitro. When treated with NTS, permeability of mOMECs decreased. RNA sequencing (RNA-Seq) of mOMECs revealed high mRNA expression of the permeability-regulating adherens junction proteins N-cadherin (CDH2) and K-cadherin (CDH6). Immunofluorescent detection of CDH2 and CDH6 confirmed expression and localized these cadherins to the cell-cell boundaries, consistent with function as components of adherens junctions. mOMECs did not express detectable levels of the typical vascular endothelial cadherin, VE-cadherin (CDH5) as determined by RNA-Seq, qPCR, western blot, and immunofluorescence. Knockdown of CDH2 or CDH6 via siRNA abrogated the NTS effect on mOMEC permeability. Collectively, these data suggest that NTS plays an ovulation-critical role in vascular permeability maintenance, and that CDH2 and CDH6 are involved in the permeability modulating effect of NTS on the ovarian microvasculature. NTS can be added to a growing number of angiogenic regulators which are critical for successful ovulation.


Asunto(s)
Células Endoteliales , Ovario , Femenino , Animales , Ovario/metabolismo , Células Endoteliales/metabolismo , Neurotensina/metabolismo , Uniones Adherentes/metabolismo , Permeabilidad Capilar , Cadherinas/genética , Cadherinas/metabolismo , Macaca/metabolismo , Permeabilidad , Endotelio Vascular/metabolismo , Mamíferos/metabolismo
4.
J Neuroinflammation ; 21(1): 130, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750510

RESUMEN

Epidemiological studies have unveiled a robust link between exposure to repetitive mild traumatic brain injury (r-mTBI) and elevated susceptibility to develop neurodegenerative disorders, notably chronic traumatic encephalopathy (CTE). The pathogenic lesion in CTE cases is characterized by the accumulation of hyperphosphorylated tau in neurons around small cerebral blood vessels which can be accompanied by astrocytes that contain phosphorylated tau, the latter termed tau astrogliopathy. However, the contribution of tau astrogliopathy to the pathobiology and functional consequences of r-mTBI/CTE or whether it is merely a consequence of aging remains unclear. We addressed these pivotal questions by utilizing a mouse model harboring tau-bearing astrocytes, GFAPP301L mice, subjected to our r-mTBI paradigm. Despite the fact that r-mTBI did not exacerbate tau astrogliopathy or general tauopathy, it increased phosphorylated tau in the area underneath the impact site. Additionally, gene ontology analysis of tau-bearing astrocytes following r-mTBI revealed profound alterations in key biological processes including immunological and mitochondrial bioenergetics. Moreover, gene array analysis of microdissected astrocytes accrued from stage IV CTE human brains revealed an immunosuppressed astroglial phenotype similar to tau-bearing astrocytes in the GFAPP301L model. Additionally, hippocampal reduction of proteins involved in water transport (AQP4) and glutamate homeostasis (GLT1) was found in the mouse model of tau astrogliopathy. Collectively, these findings reveal the importance of understanding tau astrogliopathy and its role in astroglial pathobiology under normal circumstances and following r-mTBI. The identified mechanisms using this GFAPP301L model may suggest targets for therapeutic interventions in r-mTBI pathogenesis in the context of CTE.


Asunto(s)
Acuaporina 4 , Astrocitos , Transportador 2 de Aminoácidos Excitadores , Ratones Transgénicos , Tauopatías , Proteínas tau , Astrocitos/metabolismo , Astrocitos/patología , Animales , Ratones , Proteínas tau/metabolismo , Proteínas tau/genética , Acuaporina 4/metabolismo , Acuaporina 4/genética , Tauopatías/metabolismo , Tauopatías/patología , Tauopatías/genética , Humanos , Transportador 2 de Aminoácidos Excitadores/metabolismo , Transportador 2 de Aminoácidos Excitadores/genética , Transportador 2 de Aminoácidos Excitadores/biosíntesis , Conmoción Encefálica/metabolismo , Conmoción Encefálica/patología , Masculino , Fenotipo , Ratones Endogámicos C57BL
5.
Nature ; 555(7697): 497-501, 2018 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-29565365

RESUMEN

Metal halide perovskites are of great interest for various high-performance optoelectronic applications. The ability to tune the perovskite bandgap continuously by modifying the chemical composition opens up applications for perovskites as coloured emitters, in building-integrated photovoltaics, and as components of tandem photovoltaics to increase the power conversion efficiency. Nevertheless, performance is limited by non-radiative losses, with luminescence yields in state-of-the-art perovskite solar cells still far from 100 per cent under standard solar illumination conditions. Furthermore, in mixed halide perovskite systems designed for continuous bandgap tunability (bandgaps of approximately 1.7 to 1.9 electronvolts), photoinduced ion segregation leads to bandgap instabilities. Here we demonstrate substantial mitigation of both non-radiative losses and photoinduced ion migration in perovskite films and interfaces by decorating the surfaces and grain boundaries with passivating potassium halide layers. We demonstrate external photoluminescence quantum yields of 66 per cent, which translate to internal yields that exceed 95 per cent. The high luminescence yields are achieved while maintaining high mobilities of more than 40 square centimetres per volt per second, providing the elusive combination of both high luminescence and excellent charge transport. When interfaced with electrodes in a solar cell device stack, the external luminescence yield-a quantity that must be maximized to obtain high efficiency-remains as high as 15 per cent, indicating very clean interfaces. We also demonstrate the inhibition of transient photoinduced ion-migration processes across a wide range of mixed halide perovskite bandgaps in materials that exhibit bandgap instabilities when unpassivated. We validate these results in fully operating solar cells. Our work represents an important advance in the construction of tunable metal halide perovskite films and interfaces that can approach the efficiency limits in tandem solar cells, coloured-light-emitting diodes and other optoelectronic applications.

6.
Prehosp Emerg Care ; 28(2): 215-220, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37171895

RESUMEN

OBJECTIVE: Prehospital clinicians need a practical means of providing adequate preoxygenation prior to intubation. A bag-valve-mask (BVM) can be used for preoxygenation in perfect conditions but is likely to fail in emergency settings. For this reason, many airway experts have moved away from using BVM for preoxygenation and instead suggest using a nonrebreather (NRB) mask with flush rate oxygen.Literature on preoxygenation has suggested that a NRB mask delivering flush rate oxygen (on a 15 L/min O2 regulator, maximum flow, ∼50 L/min) is noninferior to BVM at 15 L/min held with a tight seal. However, in the prehospital setting, where emergency airway management success varies, preoxygenation techniques have not been deeply explored. Our study seeks to determine whether preoxygenation can be optimally performed with NRB at flush rate oxygen. METHODS: We performed a crossover trial using healthy volunteers. Subjects underwent 3-min trials of preoxygenation with NRB mask at 25 L/min oxygen delivered from a portable tank, NRB at flush rate oxygen from a portable tank, NRB with flush rate oxygen from an onboard ambulance tank, and BVM with flush rate oxygen from an onboard ambulance tank. The primary outcome was the fraction of expired oxygen (FeO2). We compared the FeO2 of the BVM-flush to other study groups, using a noninferiority margin of 10%. RESULTS: We enrolled 30 subjects. Mean FeO2 values for NRB-25, NRB-flush ambulance, NRB-flush portable, and BVM-flush were 63% (95% confidence interval [CI] 58-68%), 74% (95%, CI 70-78%), 78% (95%, CI 74-83%), and 80% (95%, CI 75-84%), respectively. FeO2 values for NRB-flush on both portable tank and ambulance oxygen were noninferior to BVM-flush on the ambulance oxygen system (FeO2 differences of 1%, 95% CI -3% to 6%; and 6%, 95% CI 1-10%). FeO2 for the NRB-25 group was inferior to BVM-flush (FeO2 difference 16%, 95% CI 12-21%). CONCLUSIONS: Among healthy volunteers, flush rate preoxygenation using NRB masks is noninferior to BVM using either a portable oxygen tank or ambulance oxygen. This is significant because preoxygenation using NRB masks with flush rate oxygen presents a simpler alternative to the use of BVMs. Preoxygenation using NRB masks at 25 L/min from a portable tank is inferior to BVM at flush rate.


Asunto(s)
Servicios Médicos de Urgencia , Máscaras , Humanos , Manejo de la Vía Aérea/métodos , Oxígeno , Respiración Artificial/métodos , Estudios Cruzados
7.
Mol Cell Neurosci ; 125: 103855, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37084991

RESUMEN

Traumatic brain injury is a leading cause of morbidity and mortality in adults and children in developed nations. Following the primary injury, microglia, the resident innate immune cells of the CNS, initiate several inflammatory signaling cascades and pathophysiological responses that may persist chronically; chronic neuroinflammation following TBI has been closely linked to the development of neurodegeneration and neurological dysfunction. Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that have been shown to regulate several key mechanisms in the inflammatory response to TBI. Increasing evidence has shown that the modulation of the PI3K/AKT signaling pathway has the potential to influence the cellular response to inflammatory stimuli. However, directly targeting PI3K signaling poses several challenges due to its regulatory role in several cell survival pathways. We have previously identified that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN), the major negative regulator of PI3K/AKT signaling, is dysregulated following exposure to repetitive mild traumatic brain injury (r-mTBI). Moreover, this dysregulated PI3K/AKT signaling was correlated with chronic microglial-mediated neuroinflammation. Therefore, we interrogated microglial-specific PTEN as a therapeutic target in TBI by generating a microglial-specific, Tamoxifen inducible conditional PTEN knockout model using a CX3CR1 Cre recombinase mouse line PTENfl/fl/CX3CR1+/CreERT2 (mcg-PTENcKO), and exposed them to our 20-hit r-mTBI paradigm. Animals were treated with tamoxifen at 76 days post-last injury, and the effects of microglia PTEN deletion on immune-inflammatory responses were assessed at 90-days post last injury. We observed that the deletion of microglial PTEN ameliorated the proinflammatory response to repetitive brain trauma, not only reducing chronic microglial activation and proinflammatory cytokine production but also rescuing TBI-induced reactive astrogliosis, demonstrating that these effects extended beyond microglia alone. Additionally, we observed that the pharmacological inhibition of PTEN with BpV(HOpic) ameliorated the LPS-induced activation of microglial NFκB signaling in vitro. Together, these data provide support for the role of PTEN as a regulator of chronic neuroinflammation following repetitive mild TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Microglía , Animales , Ratones , Lesiones Traumáticas del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Inflamación/metabolismo , Ratones Endogámicos C57BL , Microglía/metabolismo , Enfermedades Neuroinflamatorias , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo
8.
Biol Reprod ; 108(2): 258-268, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36214501

RESUMEN

Angiogenesis within the ovarian follicle is an important component of ovulation. New capillary growth is initiated by the ovulatory surge of luteinizing hormone (LH), and angiogenesis is well underway at the time of follicle rupture. LH-stimulated follicular production of vascular growth factors has been shown to promote new capillary formation in the ovulatory follicle. The possibility that LH acts directly on ovarian endothelial cells to promote ovulatory angiogenesis has not been addressed. For these studies, ovaries containing ovulatory follicles were obtained from cynomolgus macaques and used for histological examination of ovarian vascular endothelial cells, and monkey ovarian microvascular endothelial cells (mOMECs) were enriched from ovulatory follicles for in vitro studies. mOMECs expressed LHCGR mRNA and protein, and immunostaining confirmed LHCGR protein in endothelial cells of ovulatory follicles in vivo. Human chorionic gonadotropin (hCG), a ligand for LHCGR, increased mOMEC proliferation, migration and capillary-like sprout formation in vitro. Treatment of mOMECs with hCG increased cAMP, a common intracellular signal generated by LHCGR activation. The cAMP analog dibutyryl cAMP increased mOMEC proliferation in the absence of hCG. Both the protein kinase A (PKA) inhibitor H89 and the phospholipase C (PLC) inhibitor U73122 blocked hCG-stimulated mOMEC proliferation, suggesting that multiple G-proteins may mediate LHCGR action. Human ovarian microvascular endothelial cells (hOMECs) enriched from ovarian aspirates obtained from healthy oocyte donors also expressed LHCGR. hOMECs also migrated and proliferated in response to hCG. Overall, these findings indicate that the LH surge may directly activate ovarian endothelial cells to stimulate angiogenesis of the ovulatory follicle.


Asunto(s)
Células Endoteliales , Neovascularización Fisiológica , Ovario , Receptores de HL , Animales , Femenino , Humanos , Gonadotropina Coriónica/farmacología , Gonadotropina Coriónica/metabolismo , Células Endoteliales/metabolismo , Hormona Luteinizante/farmacología , Hormona Luteinizante/metabolismo , Macaca fascicularis , Neovascularización Fisiológica/fisiología , Folículo Ovárico/metabolismo , Ovario/irrigación sanguínea , Ovario/metabolismo , Ovulación/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Receptores de HL/genética , Receptores de HL/metabolismo
9.
Am J Physiol Regul Integr Comp Physiol ; 324(2): R207-R215, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36622085

RESUMEN

Menopause is associated with adverse changes in vascular health coinciding with an increased risk of stroke and vascular cognitive impairment. However, there is significant variation in the age at menopause. The present study examined how the age at natural menopause impacts cerebrovascular reactivity and structural biomarkers of brain aging. Thirty-five healthy postmenopausal women were classified as early-onset menopause (Early; n = 19, age at menopause: 47 ± 2 yr) or later-onset menopause (Late; n = 16, age at menopause: 55 ± 2 yr). Middle cerebral artery blood velocity (MCAv), mean arterial blood pressure (MAP), and end-tidal carbon dioxide (ETCO2) were recorded during a stepped hypercapnia protocol. Reactivity was calculated as the slope of the relationship between ETCO2 and each variable of interest. Brain volumes and white matter hyperintensities (WMHs) were obtained with 3T MRI. Resting MAP was greater in the Early group (99 ± 9 mmHg) compared with the Late group (90 ± 12 mmHg; P = 0.02). Cerebrovascular reactivity, assessed using MCAv, was blunted in the Early group (1.87 ± 0.92 cm/s/mmHg) compared with the Late group (2.37 ± 0.75 cm/s/mmHg; P = 0.02). Total brain volume did not differ between groups (Early: 1.08 ± 0.07 L vs. Late: 1.07 ± 0.06 L; P = 0.66), but the Early group demonstrated greater WMH fraction compared with the Late group (Early: 0.36 ± 0.14% vs. Late: 0.25 ± 0.14%; P = 0.02). These results suggest that age at natural menopause impacts cerebrovascular function and WMH burden in healthy postmenopausal women.


Asunto(s)
Encéfalo , Circulación Cerebrovascular , Humanos , Femenino , Circulación Cerebrovascular/fisiología , Encéfalo/fisiología , Dióxido de Carbono , Hipercapnia , Menopausia , Velocidad del Flujo Sanguíneo
10.
Exp Physiol ; 108(8): 1047-1056, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37170828

RESUMEN

NEW FINDINGS: What is the central question of this study? What is the relationship between prostacyclin and cerebrovascular reactivity to hypercapnia before and after administration of a cyclooxygenase inhibitor, indomethacin, in healthy young and older adults? What is the main finding and importance? Serum prostacyclin was not related to cerebrovascular reactivity to hypercapnia before or after administration of indomethacin. However, in older adults, serum prostacyclin was related to the magnitude of change in cerebrovascular reactivity from before to after indomethacin administration. This suggests that older adults with higher serum prostacyclin may rely more on cyclooxygenase products to mediate cerebrovascular reactivity. ABSTRACT: Platelet activation may contribute to age-related cerebrovascular dysfunction by interacting with the endothelial cells that regulate the response to vasodilatory stimuli. This study evaluated the relationship between a platelet inhibitor, prostacyclin, and cerebrovascular reactivity (CVR) in healthy young (n = 35; 25 ± 4 years; 17 women, 18 men) and older (n = 12; 62 ± 2 years; 8 women, 4 men) adults, who were not daily aspirin users, before and after cyclooxygenase inhibition. Prostacyclin was determined by levels of 6-keto-prostaglandin F1α (6-keto PGF1α) in the blood. CVR was assessed by measuring the middle cerebral artery blood velocity response to hypercapnia using transcranial Doppler ultrasound before (CON) and 90 min after cyclooxygenase inhibition with indomethacin (INDO). In young adults, there were no associations between prostacyclin and middle cerebral artery CVR during CON (r = -0.14, P = 0.415) or INDO (r = 0.27, P = 0.118). In older adults, associations between prostacyclin and middle cerebral artery CVR during CON (r = 0.53, P = 0.075) or INDO (r = -0.45, P = 0.136) did not reach the threshold for significance. We also evaluated the relationship between prostacyclin and the change in CVR between conditions (ΔCVR). We found no association between ΔCVR and prostacyclin in young adults (r = 0.27, P = 0.110); however, in older adults, those with higher baseline prostacyclin levels demonstrated significantly greater ΔCVR (r = -0.74, P = 0.005). In conclusion, older adults with higher serum prostacyclin, a platelet inhibitor, may rely more on cyclooxygenase products for cerebrovascular reactivity to hypercapnia.


Asunto(s)
Epoprostenol , Hipercapnia , Masculino , Adulto Joven , Humanos , Femenino , Anciano , Epoprostenol/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Prostaglandina-Endoperóxido Sintasas , Células Endoteliales , Indometacina/farmacología , Prostaglandinas I/farmacología , Circulación Cerebrovascular/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Dióxido de Carbono
11.
Pediatr Blood Cancer ; 70(5): e30106, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36458672

RESUMEN

BACKGROUND: Understanding the landscape of clinical trials for patients with neuroblastoma may inform efforts to improve drug development. PROCEDURE: We evaluated therapeutic trials for patients with neuroblastoma from 2011 to 2020 in our search using clinical trial information from ClinicalTrials.gov, Clinicaltrialregister.eu, PubMed, and American Society of Clinical Oncology (ASCO) annual meeting collection. Trends in trials and treatments over time were evaluated qualitatively. RESULTS: A total of 192 trials met inclusion criteria. A median of 20.5 trials were started per year, which was stable over time. There were 87 (45%) phase 1, 100 (51%) phase 2, and only five (2.6%) phase 3 trials. The median time to completion was 4.9 years for phase 1 and 2 trials (no phase 3 trials reported as completed during the study period). In all, 34% of trials were international, while 20% of trials were intercontinental. Eighty-nine percent of nonmyeloablative trials included at least one novel agent. 48% of these trials studied combination therapies, and 86% of these combinations included conventional chemotherapy. Among 157 trials that included a targeted agent, 78 targets were identified, with GD2 being the primary target under investigation in 16.7% of these trials. Only eight trials were included in regulatory decisions, which led to European Medicines Agency (EMA) or Food and Drug Administration (FDA) approval for neuroblastoma. CONCLUSIONS: The large number of trials initiated per year, the range of targets, and the rate of intercontinental collaboration are encouraging. The paucity of late-stage trials, the prolonged trial duration, and relative lack of combination studies are major causes of concern. This work will inform future drug development for neuroblastoma.


Asunto(s)
Antineoplásicos , Neuroblastoma , Humanos , Neuroblastoma/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Terapia Combinada , Desarrollo de Medicamentos
12.
Cancer ; 128(21): 3775-3783, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36101004

RESUMEN

BACKGROUND: International standardized criteria for eligibility, evaluable disease sites, and disease response assessment in patients with refractory, progressive, or relapsed high-risk neuroblastoma enrolled in early-phase clinical trials are lacking. METHODS: A National Cancer Institute-sponsored Clinical Trials Planning Meeting was convened to develop an international consensus to refine the tumor site eligibility criteria and evaluation of disease response for early-phase clinical trials in children with high-risk neuroblastoma. RESULTS: Standardized data collection of patient and disease characteristics (including specified genomic data), eligibility criteria, a definition of evaluable disease, and response evaluations for primary and metastatic sites of disease were developed. Eligibility included two distinct patient groups: progressive disease and refractory disease. The refractory disease group was subdivided into responding persistent disease and stable persistent disease to better capture the clinical heterogeneity of refractory neuroblastoma. Requirements for defining disease evaluable for a response assessment were provided; they included requirements for biopsy to confirm viable neuroblastoma and/or ganglioneuroblastoma in those patients with soft tissue or bone disease not avid for iodine-123 meta-iodobenzylguanidine. Standardized evaluations for response components and time intervals for response evaluations were established. CONCLUSIONS: The use of international consensus eligibility, evaluability, and response criteria for early-phase clinical studies will facilitate the collection of comparable data across international trials and promote more rapid identification of effective treatment regimens for high-risk neuroblastoma.


Asunto(s)
3-Yodobencilguanidina , Neuroblastoma , 3-Yodobencilguanidina/uso terapéutico , Niño , Consenso , Humanos , National Cancer Institute (U.S.) , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/terapia , Resultado del Tratamiento , Estados Unidos
13.
Respir Res ; 23(1): 326, 2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36463179

RESUMEN

BACKGROUND: Bacterial pneumonia is a major risk factor for acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Pseudomonas aeruginosa (PA), an opportunistic pathogen with an increasing resistance acquired against multiple drugs, is one of the main causative agents of ALI and ARDS in diverse clinical settings. Given the anti-inflammatory role of the cannabinoid-2 receptor (CB2R), the effect of CB2R activation in the regulation of PA-induced ALI and inflammation was tested in a mouse model as an alternative to conventional antibiotic therapy. METHODS: In order to activate CB2R, a selective synthetic agonist, JWH133, was administered intraperitoneally (i.p.) to C57BL/6J mice. Furthermore, SR144528 (a selective CB2R antagonist) was administered in combination with JWH133 to test the specificity of the CB2R-mediated effect. PA was administered intratracheally (i.t.) for induction of pneumonia in mice. At 24 h after PA exposure, lung mechanics were measured using the FlexiVent system. The total cell number, protein content, and neutrophil population in the bronchoalveolar lavage fluid (BALF) were determined. The bacterial load in the whole lung was also measured. Lung injury was evaluated by histological examination and PA-induced inflammation was assessed by measuring the levels of BALF cytokines and chemokines. Neutrophil activation (examined by immunofluorescence and immunoblot) and PA-induced inflammatory signaling (analyzed by immunoblot) were also studied. RESULTS: CB2R activation by JWH133 was found to significantly reduce PA-induced ALI and the bacterial burden. CB2R activation also suppressed the PA-induced increase in immune cell infiltration, neutrophil population, and inflammatory cytokines. These effects were abrogated by a CB2R antagonist, SR144528, further confirming the specificity of the CB2R-mediated effects. CB2R-knock out (CB2RKO) mice had a significantly higher level of PA-induced inflammation as compared to that in WT mice. CB2R activation diminished the excess activation of neutrophils, whereas mice lacking CB2R had elevated neutrophil activation. Pharmacological activation of CB2R significantly reduced the PA-induced NF-κB and NLRP3 inflammasome activation, whereas CB2KO mice had elevated NLRP3 inflammasome. CONCLUSION: Our findings indicate that CB2R activation ameliorates PA-induced lung injury and inflammation, thus paving the path for new therapeutic avenues against PA pneumonia.


Asunto(s)
Lesión Pulmonar Aguda , Cannabinoides , Inflamación , Infecciones por Pseudomonas , Receptor Cannabinoide CB2 , Animales , Ratones , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/prevención & control , Cannabinoides/farmacología , Cannabinoides/uso terapéutico , Citocinas , Inflamasomas/genética , Inflamasomas/inmunología , Inflamación/genética , Inflamación/inmunología , Inflamación/prevención & control , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR , Pseudomonas aeruginosa , Receptores de Cannabinoides , Síndrome de Dificultad Respiratoria , Receptor Cannabinoide CB2/genética , Receptor Cannabinoide CB2/inmunología , Infecciones por Pseudomonas/genética , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/prevención & control , Modelos Animales de Enfermedad
14.
Neurobiol Dis ; 150: 105237, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33383188

RESUMEN

A pathological characteristic of repetitive traumatic brain injury (TBI) is the deposition of hyperphosphorylated and aggregated tau species in the brain and increased levels of extracellular monomeric tau are believed to play a role in the pathogenesis of neurodegenerative tauopathies. The pathways by which extracellular tau is eliminated from the brain, however, remains elusive. The purpose of this study was to examine tau uptake by cerebrovascular cells and the effect of TBI on these processes. We found monomeric tau interacts with brain vascular mural cells (pericytes and smooth muscle cells) to a greater extent than other cerebrovascular cells, indicating mural cells may contribute to the elimination of extracellular tau, as previously described for other solutes such as beta-amyloid. Consistent with other neurodegenerative disorders, we observed a progressive decline in cerebrovascular mural cell markers up to 12 months post-injury in a mouse model of repetitive mild TBI (r-mTBI) and human TBI brain specimens, when compared to control. These changes appear to reflect mural cell degeneration and not cellular loss as no difference in the mural cell population was observed between r-mTBI and r-sham animals as determined through flow cytometry. Moreover, freshly isolated r-mTBI cerebrovessels showed reduced tau uptake at 6 and 12 months post-injury compared to r-sham animals, which may be the result of diminished cerebrovascular endocytosis, as caveolin-1 levels were significantly decreased in mouse r-mTBI and human TBI cerebrovessels compared to their respective controls. Further emphasizing the interaction between mural cells and tau, similar reductions in mural cell markers, tau uptake, and caveolin-1 were observed in cerebrovessels from transgenic mural cell-depleted animals. In conclusion, our studies indicate repeated injuries to the brain causes chronic mural cell degeneration, reducing the caveolar-mediated uptake of tau by these cells. Alterations in tau uptake by vascular mural cells may contribute to tau deposition in the brain following head trauma and could represent a novel therapeutic target for TBI or other neurodegenerative disorders.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Conmoción Encefálica/metabolismo , Encéfalo/metabolismo , Células Endoteliales/metabolismo , Microglía/metabolismo , Miocitos del Músculo Liso/metabolismo , Pericitos/metabolismo , Proteínas tau/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Encéfalo/irrigación sanguínea , Caveolina 1/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Músculo Liso Vascular/citología , Presenilina-1/genética , Recurrencia
16.
Am J Physiol Regul Integr Comp Physiol ; 321(2): R208-R219, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34161746

RESUMEN

Structural and functional changes in the cerebral vasculature occur with advancing age, which may lead to impaired neurovascular coupling (NVC) and cognitive decline. Cyclooxygenase (COX) inhibition abolishes age-related differences in cerebrovascular reactivity, but it is unclear if COX inhibition impacts NVC. The purpose of this study was to examine the influence of aging on NVC before and after COX inhibition. Twenty-three young (age = 25 ± 4 yr) and 21 older (age = 64 ± 5 yr) adults completed two levels of difficulty of the Stroop and n-back tests before and after COX inhibition. Middle cerebral artery blood velocity (MCAv) was measured using transcranial Doppler ultrasound and mean arterial blood pressure (MAP) was measured using a finger cuff. Hemodynamic variables were measured at rest and in response to cognitive challenges. During the Stroop test, older adults demonstrated a greater increase in MCAv (young: 2.2 ± 6.8% vs. older: 5.9 ± 5.8%; P = 0.030) and MAP (young: 2.0 ± 4.9% vs. older: 4.8 ± 4.9%; P = 0.036) compared with young adults. There were no age-related differences during the n-back test. COX inhibition reduced MCAv by 30% in young and 26% in older adults (P < 0.001 for both). During COX inhibition, there were no age-related differences in the percent change in MCAv or MAP in response to the cognitive tests. Our results show that older adults require greater increases in MCAv and MAP during a test of executive function compared with young adults and that any age-related differences in NVC were abolished during COX inhibition. Collectively, this suggests that aging is associated with greater NVC necessary to accomplish a cognitive task.


Asunto(s)
Circulación Cerebrovascular/efectos de los fármacos , Cognición , Envejecimiento Cognitivo/psicología , Inhibidores de la Ciclooxigenasa/farmacología , Hemodinámica/efectos de los fármacos , Indometacina/farmacología , Arteria Cerebral Media/efectos de los fármacos , Acoplamiento Neurovascular/efectos de los fármacos , Adolescente , Adulto , Factores de Edad , Anciano , Función Ejecutiva , Femenino , Humanos , Masculino , Memoria a Corto Plazo , Persona de Mediana Edad , Arteria Cerebral Media/diagnóstico por imagen , Test de Stroop , Factores de Tiempo , Adulto Joven
17.
J Int Neuropsychol Soc ; 27(8): 761-775, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33952365

RESUMEN

Exercise is associated with higher cognitive function and is a promising intervention to reduce the risk of dementia. With advancing age, there are changes in the vasculature that have important clinical implications for brain health and cognition. Primary aging and vascular risk factors are associated with increases in arterial stiffness and pulse pressure, and reductions in peripheral vascular function. OBJECTIVE: The purpose is to discuss the epidemiological, observational, and mechanistic evidence regarding the link between age-related changes in vascular health and brain health. METHODS: We performed a literature review and integrated with our published data. RESULTS: Epidemiological evidence suggests a link between age-related increases in arterial stiffness and lower cognitive function, which may be mediated by cerebral vascular function, including cerebral vasoreactivity and cerebral pulsatility. Age-associated impairments in central arterial stiffness and peripheral vascular function have been attenuated or reversed through lifestyle behaviors such as exercise. Greater volumes of habitual exercise and higher cardiorespiratory fitness are associated with beneficial effects on both peripheral vascular health and cognition. Yet, the extent to which exercise directly influences cerebral vascular function and brain health, as well as the associated mechanisms remains unclear. CONCLUSION: Although there is evidence that exercise positively impacts cerebral vascular function, more research is necessary in humans to optimize experimental protocols and address methodological limitations and physiological considerations. Understanding the impact of exercise on cerebral vascular function is important for understanding the association between exercise and brain health and may inform future intervention studies that seek to improve cognition.


Asunto(s)
Rigidez Vascular , Envejecimiento , Presión Sanguínea , Encéfalo , Ejercicio Físico , Humanos
18.
Pediatr Blood Cancer ; 68(7): e29047, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33860611

RESUMEN

While considerable efforts and progress in our understanding of the long-term toxicities of surgery, radiation and chemotherapy in children with cancer have been made over the last 5 decades, there continues to be a wide gap in our knowledge of the long-term health impact of most novel targeted and immunotherapy agents. To address this gap, ACCELERATE, a multi-stakeholder collaboration of clinical and translational academics, regulators from the EMA and FDA, patient/family advocates and members spanning small biotechnology through to large pharmaceutical companies have initiated the development of an international long-term follow-up data registry to collect this important information prospectively. Providing critical safety data on the long-term use of these approved and investigational therapies in children will support the regulatory requirements and labeling information. It will also provide the necessary insight to help guide physicians and families on the appropriateness of a targeted or immune therapy for their child and inform survivorship planning.


Asunto(s)
Neoplasias , Adolescente , Niño , Atención a la Salud , Familia , Estudios de Seguimiento , Humanos , Neoplasias/tratamiento farmacológico , Supervivencia
19.
Pediatr Blood Cancer ; 68(3): e28794, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33205902

RESUMEN

BACKGROUND: Long-term outcome remains poor for children with high-risk neuroblastoma (five-year overall survival [OS] ∼50%). Our objectives were to (a) identify prognostic biomarkers and apply them in a nomogram to identify the subgroup of ultra-high-risk patients at highest risk of disease progression/death, for whom novel frontline therapy is urgently needed; and (b) validate the nomogram in an independent cohort. METHODS: A total of 1820 high-risk patients (≥18 months old with metastatic neuroblastoma), diagnosed 1998-2015, from the International Neuroblastoma Risk Groups (INRG) Data Commons were analyzed in a retrospective cohort study. Using multivariable Cox regression of OS from diagnosis, a nomogram was created from prognostic biomarkers to predict three-year OS. External validation was performed using the SIOPEN HR-NBL1 trial cohort (n = 521), evidenced by receiver operating characteristic curves. RESULTS: The nomogram, including MYCN status (P < 0.0001), lactate dehydrogenase (LDH) (P = 0.0007), and presence of bone marrow metastases (P = 0.004), had robust performance and was validated. Applying the nomogram at diagnosis (a) gives prognosis of an individual patient and (b) identifies patients predicted to have poor outcome (three-year OS was 30% ± 5% for patients with a nomogram score of > 82 points; 58% ± 1% for those ≤82 points). Median follow-up time was 5.5 years (range, 0-14.1). CONCLUSIONS: In high-risk neuroblastoma, a novel, publicly available nomogram using prognostic biomarkers (MYCN status, LDH, presence of bone marrow metastases; https://neuroblastoma.shinyapps.io/High-Risk-Neuroblastoma-Nomogram/) has the flexibility to apply a clinically suitable and context-specific cutoff to identify patients at highest risk of death. This will facilitate testing urgently needed new frontline treatment options to improve outcome for these children.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Neoplasias de la Médula Ósea/mortalidad , L-Lactato Deshidrogenasa/metabolismo , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/mortalidad , Nomogramas , Factores de Edad , Neoplasias de la Médula Ósea/tratamiento farmacológico , Neoplasias de la Médula Ósea/metabolismo , Neoplasias de la Médula Ósea/secundario , Preescolar , Femenino , Estudios de Seguimiento , Amplificación de Genes , Humanos , Masculino , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/metabolismo , Neuroblastoma/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
20.
Respir Res ; 21(1): 132, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32471489

RESUMEN

BACKGROUND: Chronic tissue injury was shown to induce progressive scarring in fibrotic diseases such as idiopathic pulmonary fibrosis (IPF), while an array of repair/regeneration and stress responses come to equilibrium to determine the outcome of injury at the organ level. In the lung, type I alveolar epithelial (ATI) cells constitute the epithelial barrier, while type II alveolar epithelial (ATII) cells play a pivotal role in regenerating the injured distal lungs. It had been demonstrated that eukaryotic cells possess repair machinery that can quickly patch the damaged plasma membrane after injury, and our previous studies discovered the membrane-mending role of Tripartite motif containing 72 (TRIM72) that expresses in a limited number of tissues including the lung. Nevertheless, the role of alveolar epithelial cell (AEC) repair in the pathogenesis of IPF has not been examined yet. METHOD: In this study, we tested the specific roles of TRIM72 in the repair of ATII cells and the development of lung fibrosis. The role of membrane repair was accessed by saponin assay on isolated primary ATII cells and rat ATII cell line. The anti-fibrotic potential of TRIM72 was tested with bleomycin-treated transgenic mice. RESULTS: We showed that TRIM72 was upregulated following various injuries and in human IPF lungs. However, TRIM72 expression in ATII cells of the IPF lungs had aberrant subcellular localization. In vitro studies showed that TRIM72 repairs membrane injury of immortalized and primary ATIIs, leading to inhibition of stress-induced p53 activation and reduction in cell apoptosis. In vivo studies demonstrated that TRIM72 protects the integrity of the alveolar epithelial layer and reduces lung fibrosis. CONCLUSION: Our results suggest that TRIM72 protects injured lungs and ameliorates fibrosis through promoting post-injury repair of AECs.


Asunto(s)
Células Epiteliales Alveolares/metabolismo , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/prevención & control , Pulmón/metabolismo , Proteínas de Motivos Tripartitos/biosíntesis , Células Epiteliales Alveolares/efectos de los fármacos , Animales , Bleomicina/toxicidad , Femenino , Células HEK293 , Humanos , Fibrosis Pulmonar Idiopática/inducido químicamente , Pulmón/efectos de los fármacos , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Noqueados , Proteínas Recombinantes/biosíntesis
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