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1.
Blood ; 143(16): 1586-1598, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38211335

RESUMO

ABSTRACT: Maintenance of quiescence and DNA replication dynamics are 2 paradoxical requirements for the distinct states of dormant and active hematopoietic stem cells (HSCs), which are required to preserve the stem cell reservoir and replenish the blood cell system in response to hematopoietic stress, respectively. Here, we show that key self-renewal factors, ß-catenin or Hoxa9, largely dispensable for HSC integrity, in fact, have dual functions in maintaining quiescence and enabling efficient DNA replication fork dynamics to preserve the functionality of hematopoietic stem and progenitor cells (HSPCs). Although ß-catenin or Hoxa9 single knockout (KO) exhibited mostly normal hematopoiesis, their coinactivation led to severe hematopoietic defects stemmed from aberrant cell cycle, DNA replication, and damage in HSPCs. Mechanistically, ß-catenin and Hoxa9 function in a compensatory manner to sustain key transcriptional programs that converge on the pivotal downstream target and epigenetic modifying enzyme, Prmt1, which protects the quiescent state and ensures an adequate supply of DNA replication and repair factors to maintain robust replication fork dynamics. Inactivation of Prmt1 phenocopied both cellular and molecular phenotypes of ß-catenin/Hoxa9 combined KO, which at the same time could also be partially rescued by Prmt1 expression. The discovery of the highly resilient ß-catenin/Hoxa9/Prmt1 axis in protecting both quiescence and DNA replication dynamics essential for HSCs at different key states provides not only novel mechanistic insights into their intricate regulation but also a potential tractable target for therapeutic intervention.


Assuntos
Células-Tronco Hematopoéticas , beta Catenina , beta Catenina/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Ciclo Celular , Divisão Celular , Replicação do DNA
2.
Cardiol Young ; 34(3): 581-587, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37608743

RESUMO

OBJECTIVES: Poor oral feeding is a known contributor to growth challenges in neonates with complex CHD who require early surgery. Almost 60% of these infants do not achieve full oral feeding by hospital discharge. This study's objective was to identify predictors of the inability to achieve full oral feeding by discharge in neonates with complex CHD following surgical intervention with cardiopulmonary bypass. STUDY DESIGN: A retrospective analysis of a prospective study of 192 full-term neonates with complex CHD was performed. A stepwise selection logistic regression model was developed to predict oral feeding status at hospital discharge. Univariate subgroup analysis was performed with groups determined based on a CHD classification system. RESULTS: 58% of neonates (112/192) failed to achieve full oral feeding by hospital discharge. A logistic regression model identified duration of deep hypothermic circulatory arrest and reintubation as predictors of the inability to achieve full oral feeding. Among neonates who achieved full oral feeding by discharge (42%), only 7.5% did so after postoperative day 10. Brain maturation, brain injury, and preoperative oral feeding were not predictors of full postoperative oral feeding. CONCLUSIONS: Many infants with CHD fail to achieve full oral feeding by time of hospital discharge. Longer duration of deep hypothermic circulatory arrest and increased number of intubations were predictive of poor feeding after surgery. Prolonging hospitalisation solely to achieve full oral feeding after postoperative day ten is of limited utility; earlier discharge should be promoted to avoid negative impacts on neonatal neurodevelopment as unintended consequences of lengthy hospitalisations.


Assuntos
Lesões Encefálicas , Hospitalização , Lactente , Recém-Nascido , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Alta do Paciente
3.
PLoS One ; 18(12): e0295370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38096183

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0078428.].

4.
Metabolites ; 13(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37999249

RESUMO

Cardiopulmonary bypass (CPB) provides cerebral oxygenation and blood flow (CBF) during neonatal congenital heart surgery, but the impacts of CPB on brain oxygen supply and metabolic demands are generally unknown. To elucidate this physiology, we used diffuse correlation spectroscopy and frequency-domain diffuse optical spectroscopy to continuously measure CBF, oxygen extraction fraction (OEF), and oxygen metabolism (CMRO2) in 27 neonatal swine before, during, and up to 24 h after CPB. Concurrently, we sampled cerebral microdialysis biomarkers of metabolic distress (lactate-pyruvate ratio) and injury (glycerol). We applied a novel theoretical approach to correct for hematocrit variation during optical quantification of CBF in vivo. Without correction, a mean (95% CI) +53% (42, 63) increase in hematocrit resulted in a physiologically improbable +58% (27, 90) increase in CMRO2 relative to baseline at CPB initiation; following correction, CMRO2 did not differ from baseline at this timepoint. After CPB initiation, OEF increased but CBF and CMRO2 decreased with CPB time; these temporal trends persisted for 0-8 h following CPB and coincided with a 48% (7, 90) elevation of glycerol. The temporal trends and glycerol elevation resolved by 8-24 h. The hematocrit correction improved quantification of cerebral physiologic trends that precede and coincide with neurological injury following CPB.

5.
Front Pediatr ; 11: 1125985, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425272

RESUMO

Background: Surgical procedures involving the aortic arch present unique challenges to maintaining cerebral perfusion, and optimal neuroprotective strategies to prevent neurological injury during such high-risk procedures are not completely understood. The use of antegrade cerebral perfusion (ACP) has gained favor as a neuroprotective strategy over deep hypothermic circulatory arrest (DHCA) due to the ability to selectively perfuse the brain. Despite this theoretical advantage over DHCA, there has not been conclusive evidence that ACP is superior to DHCA. One potential reason for this is the incomplete understanding of ideal ACP flow rates to prevent both ischemia from underflowing and hyperemia and cerebral edema from overflowing. Critically, there are no continuous, noninvasive measurements of cerebral blood flow (CBF) and cerebral oxygenation (StO2) to guide ACP flow rates and help develop standard clinical practices. The purpose of this study is to demonstrate the feasibility of using noninvasive, diffuse optical spectroscopy measurements of CBF and cerebral oxygenation during the conduct of ACP in human neonates undergoing the Norwood procedure. Methods: Four neonates prenatally diagnosed with hypoplastic left heart syndrome (HLHS) or a similar variant underwent the Norwood procedure with continuous intraoperative monitoring of CBF and cerebral oxygen saturation (StO2) using two non-invasive optical techniques, namely diffuse correlation spectroscopy (DCS) and frequency-domain diffuse optical spectroscopy (FD-DOS). Changes in CBF and StO2 due to ACP were calculated by comparing these parameters during a stable 5 min period of ACP to the last 5 min of full-body CPB immediately prior to ACP initiation. Flow rates for ACP were left to the discretion of the surgeon and ranged from 30 to 50 ml/kg/min, and all subjects were cooled to 18°C prior to initiation of ACP. Results: During ACP, the continuous optical monitoring demonstrated a median (IQR) percent change in CBF of -43.4% (38.6) and a median (IQR) absolute change in StO2 of -3.6% (12.3) compared to a baseline period during full-body cardiopulmonary bypass (CPB). The four subjects demonstrated varying responses in StO2 due to ACP. ACP flow rates of 30 and 40 ml/kg/min (n = 3) were associated with decreased CBF during ACP compared to full-body CPB. Conversely, one subject with a higher flow6Di rate of 50 ml/kg/min demonstrated increased CBF and StO2 during ACP. Conclusions: This feasibility study demonstrates that novel diffuse optical technologies can be utilized for improved neuromonitoring in neonates undergoing cardiac surgery where ACP is utilized. Future studies are needed to correlate these findings with neurological outcomes to inform best practices during ACP in these high-risk neonates.

6.
J Am Heart Assoc ; 12(7): e025516, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36974759

RESUMO

Background Infants with congenital heart disease (CHD) are at risk for white matter injury (WMI) before neonatal heart surgery. Better knowledge of the causes of preoperative WMI may provide insights into interventions that improve neurodevelopmental outcomes in these patients. Methods and Results A prospective single-center study of preoperative WMI in neonates with CHD recorded data on primary cardiac diagnosis, maternal-fetal environment (MFE), delivery type, subject anthropometrics, and preoperative care. Total maturation score and WMI were assessed, and stepwise logistic regression modeling selected risk factors for WMI. Among subjects with severe CHD (n=183) who received a preoperative brain magnetic resonance imaging, WMI occurred in 40 (21.9%) patients. WMI prevalence (21.4%-22.1%) and mean volumes (119.7-160.4 mm3) were similar across CHD diagnoses. Stepwise logistic regression selected impaired MFE (odds ratio [OR], 2.85 [95% CI, 1.29-6.30]), male sex (OR, 2.27 [95% CI, 1.03-5.36]), and older age at surgery/magnetic resonance imaging (OR, 1.20 per day [95% CI, 1.03-1.41]) as risk factors for preoperative WMI and higher total maturation score values (OR, 0.65 per unit increase [95% CI, 0.43-0.95]) as protective. A quarter (24.6%; n=45) of subjects had ≥1 components of impaired MFE (gestational diabetes [n=12; 6.6%], gestational hypertension [n=11; 6.0%], preeclampsia [n=2; 1.1%], tobacco use [n=9; 4.9%], hypothyroidism [n=6; 3.3%], and other [n=16; 8.7%]). In a subset of 138 subjects, an exploratory analysis of additional MFE-related factors disclosed other potential risk factors for WMI. Conclusions This study is the first to identify impaired MFE as an important risk factor for preoperative WMI. Vulnerability to preoperative WMI was shared across CHD diagnoses.


Assuntos
Lesões Encefálicas , Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Substância Branca , Recém-Nascido , Lactente , Gravidez , Feminino , Humanos , Masculino , Estudos Prospectivos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/patologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/epidemiologia , Lesões Encefálicas/etiologia , Imageamento por Ressonância Magnética/métodos , Fatores de Risco
7.
Environ Toxicol Chem ; 42(6): 1309-1325, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942377

RESUMO

Vitellogenin (VTG), an egg yolk precursor, is abnormally produced by male and juvenile oviparous species after exposure to estrogens. Plasma VTG in loggerhead sea turtles (Caretta caretta) helped us understand their reproductive maturation and investigate it as a biomarker of contaminant exposure. The presence of VTG was screened in plasma from 404 loggerheads from the northwestern Atlantic Ocean using a freshwater turtle antibody in western blots. The concentrations of VTG were semiquantified using band intensities calibrated to results from a loggerhead antibody enzyme-linked immunoassay. The detection and concentrations of VTG were in (from highest to lowest): nesting females, in-water adult females, subadult females, smaller females, unknown sex, and males. Loggerheads from this region begin vitellogenesis at ≅77 cm straight carapace length. We classified VTG expression as abnormal in nine male or juvenile turtles. Organochlorine contaminant (OC) concentrations were measured in blood and/or fat biopsies of some turtles. One abnormal VTG female had the second highest fat polychlorinated biphenyl (PCB) and 4,4'-dichlorodiphenyldichloroethylene concentrations compared among 43 VTG-negative juveniles. The nine VTG-abnormal turtles had average blood PCB concentrations 8.5% higher, but not significantly different, than 46 VTG-negative juveniles (p = 0.453). In turtles less than 77 cm, blood PCB concentrations were significantly, but weakly, correlated with semiquantified VTG concentrations (tau = 0.1, p = 0.004). Greater blood OC concentrations were found in adult females than in males, which motivated the creation of a conceptual model of OC, VTG, and hormone concentrations across a reproductive cycle. A decision tree is also provided incorporating VTG as a sexing tool. Abnormal VTG expression cannot conclusively be linked to endocrine disruption caused by these OC concentrations. Studies should further investigate causes of abnormal VTG expression in wild sea turtles. Environ Toxicol Chem 2023;42:1309-1325. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Bifenilos Policlorados , Tartarugas , Animais , Feminino , Masculino , Vitelogeninas/metabolismo , Tartarugas/metabolismo , Bifenilos Policlorados/metabolismo , Anticorpos/metabolismo , Estrogênios/metabolismo
8.
Metabolites ; 12(8)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36005609

RESUMO

Neonates undergoing cardiac surgery involving aortic arch reconstruction are at an increased risk for hypoxic-ischemic brain injury. Deep hypothermia is utilized to help mitigate this risk when periods of circulatory arrest are needed for surgical repair. Here, we investigate correlations between non-invasive optical neuromonitoring of cerebral hemodynamics, which has recently shown promise for the prediction of postoperative white matter injury in this patient population, and invasive cerebral microdialysis biomarkers. We compared cerebral tissue oxygen saturation (StO2), relative total hemoglobin concentration (rTHC), and relative cerebral blood flow (rCBF) measured by optics against the microdialysis biomarkers of metabolic stress and injury (lactate-pyruvate ratio (LPR) and glycerol) in neonatal swine models of deep hypothermic cardiopulmonary bypass (DHCPB), selective antegrade cerebral perfusion (SACP), and deep hypothermic circulatory arrest (DHCA). All three optical parameters were negatively correlated with LPR and glycerol in DHCA animals. Elevation of LPR was found to precede the elevation of glycerol by 30-60 min. From these data, thresholds for the detection of hypoxic-ischemia-associated cerebral metabolic distress and neurological injury are suggested. In total, this work provides insight into the timing and mechanisms of neurological injury following hypoxic-ischemia and reports a quantitative relationship between hypoxic-ischemia severity and neurological injury that may inform DHCA management.

9.
J Thorac Cardiovasc Surg ; 163(1): e47-e58, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33485668

RESUMO

OBJECTIVE: We aimed to determine the effects of selective antegrade cerebral perfusion compared with other perfusion strategies on indices of cerebral blood flow, oxygenation, cellular stress, and mitochondrial function. METHODS: One-week-old piglets (n = 41) were assigned to 5 treatment groups. Thirty-eight were placed on cardiopulmonary bypass. Of these, 30 were cooled to 18°C and underwent deep hypothermic circulatory arrest (n = 10), underwent selective antegrade cerebral perfusion at 10 mL/kg/min (n = 10), or remained on continuous cardiopulmonary bypass (deep hypothermic cardiopulmonary bypass, n = 10) for 40 minutes. Other subjects remained on normothermic cardiopulmonary bypass (n = 8) or underwent sham surgery (n = 3). Novel, noninvasive optical measurements recorded cerebral blood flow, cerebral tissue oxyhemoglobin concentration, oxygen extraction fraction, total hemoglobin concentration, and cerebral metabolic rate of oxygen. Invasive measurements of cerebral microdialysis and cerebral blood flow were recorded. Cerebral mitochondrial respiration and reactive oxygen species generation were assessed after the piglets were killed. RESULTS: During hypothermia, deep hypothermic circulatory arrest piglets experienced increases in oxygen extraction fraction (P < .001), indicating inadequate matching of oxygen supply and demand. Deep hypothermic cardiopulmonary bypass had higher cerebral blood flow (P = .046), oxyhemoglobin concentration (P = .019), and total hemoglobin concentration (P = .070) than selective antegrade cerebral perfusion, indicating greater oxygen delivery. Deep hypothermic circulatory arrest demonstrated worse mitochondrial function (P < .05), increased reactive oxygen species generation (P < .01), and increased markers of cellular stress (P < .01). Reactive oxygen species generation was increased in deep hypothermic cardiopulmonary bypass compared with selective antegrade cerebral perfusion (P < .05), but without significant microdialysis evidence of cerebral cellular stress. CONCLUSIONS: Selective antegrade cerebral perfusion meets cerebral metabolic demand and mitigates cerebral mitochondrial reactive oxygen species generation. Excess oxygen delivery during deep hypothermia may have deleterious effects on cerebral mitochondria that may contribute to adverse neurologic outcomes. We describe noninvasive measurements that may help guide perfusion strategies.


Assuntos
Encéfalo , Ponte Cardiopulmonar , Circulação Cerebrovascular/fisiologia , Parada Circulatória Induzida por Hipotermia Profunda , Oxigênio , Reperfusão/métodos , Animais , Animais Recém-Nascidos , Análise da Demanda Biológica de Oxigênio , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/métodos , Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Parada Circulatória Induzida por Hipotermia Profunda/métodos , Mitocôndrias/fisiologia , Imagem Óptica/métodos , Oxigênio/efeitos adversos , Oxigênio/metabolismo , Consumo de Oxigênio/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Análise Espectral/métodos , Suínos
10.
Semin Thorac Cardiovasc Surg ; 34(4): 1275-1284, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34508811

RESUMO

Cardiac surgery utilizing circulatory arrest is most commonly performed under deep hypothermia (∼18°C) to suppress tissue oxygen demand and provide neuroprotection during operative circulatory arrest. Studies investigating the effects of deep hypothermic circulatory arrest (DHCA) on neurodevelopmental outcomes of patients with congenital heart disease give conflicting results. Here, we address these issues by quantifying changes in cerebral oxygen saturation, blood flow, and oxygen metabolism in neonates during DHCA and investigating the association of these changes with postoperative brain injury. Neonates with critical congenital heart disease undergoing DHCA were recruited for continuous intraoperative monitoring of cerebral oxygen saturation (ScO2) and an index of cerebral blood flow (CBFi) using 2 noninvasive optical techniques, diffuse optical spectroscopy (DOS) and diffuse correlation spectroscopy (DCS). Pre- and postoperative brain magnetic resonance imaging (MRI) was performed to detect white matter injury (WMI). Fifteen neonates were studied, and 11/15 underwent brain MRI. During DHCA, ScO2 decreased exponentially in time with a median decay rate of -0.04 min-1. This decay rate was highly variable between subjects. Subjects who had larger decreases in ScO2 during DHCA were more likely to have postoperative WMI (P = 0.02). Cerebral oxygen extraction persists during DHCA and varies widely from patient-to-patient. Patients with a higher degree of oxygen extraction during DHCA were more likely to show new WMI in postoperative MRI. These findings suggest cerebral oxygen extraction should be monitored during DHCA to identify patients at risk for hypoxic-ischemic injury, and that current commercial cerebral oximeters may underestimate cerebral oxygen extraction.


Assuntos
Lesões Encefálicas , Parada Circulatória Induzida por Hipotermia Profunda , Recém-Nascido , Humanos , Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Resultado do Tratamento , Circulação Cerebrovascular , Encéfalo/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/etiologia , Oxigênio , Ponte Cardiopulmonar/efeitos adversos
11.
Aquat Conserv ; 31(2): 408-419, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34334992

RESUMO

Although the frequency of occurrence of plastic ingestion in the large-sized dolphinfish and tunas taken by the Hawai'i longline fishery is very low (frequency of occurrence < 5% of sampled individuals), the ingestion of plastic in smaller-sized specimens caught with pole-and-line gear by commercial and recreational fishers has not been investigated.This study examined ingestion of >0.25 mm marine plastic debris (MPD) by four predatory fish species caught by commercial fishers around the Main Hawaiian Islands, and documented ingestion in three species: 85.7% of albacore tuna (n = 7), 40.0% of skipjack tuna (n = 10) and 12.5% of dolphinfish (n = 8).Yellowfin tuna (n = 10) did not contain any MPD, probably owing to the high proportion of empty stomachs (60%).For skipjack tuna, the frequency of occurrence of MPD ingestion was significantly higher for the smaller-sized specimens caught with pole-and-line (40%), compared with the larger-sized specimens caught with longlines (0%).For dolphinfish, the frequency of occurrence of MPD ingestion was similar for the similar-sized specimens caught with pole-and-line and with longlines.The ingested MPD items were micro-meso plastics, between 1 and 25 mm. While most ingested items were fragments, albacore also ingested line and skipjack also ingested sheets.The predatory fishes ingested light MPD items that float in sea water, but there were species-specific differences in their polymer composition: albacore contained more polypropylene and polyethylene, and skipjack contained more elastomers, characterized by a high percentage of ester plasticizers.Altogether, these results suggest that albacore and skipjack tunas ingest plastic of different types and polymers. Yet more research is needed to understand how differences in vertical distribution, foraging ecology and diet influence the MPD sampled by these predatory fish species.

13.
Int J Nurs Stud ; 107: 103576, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32380259

RESUMO

BACKGROUND: End of life care is often inadequate for people with dementia. Advanced care planning (ACP) has the potential to improve outcomes for people with dementia. The aim of this review is to establish the strength of the evidence and provide decision makers with a clear understanding of what is known about ACP for people living with dementia. DESIGN: Evidence synthesis including systematic reviews and primary studies. PROSPERO registration: CRD42018107718. DATA SOURCES: PubMed, CINAHL Plus, SCOPUS, Social Care Online and Cochrane Library were searched (July 2018). No year limit applied. To be included, reviews had to evaluate effectiveness of ACP for people with dementia or report on views and experiences of ACP from the perspective of people with dementia, carers, or health and care professionals. Additional searches (September 2018) were conducted to identify recent primary studies not included in the reviews. REVIEW METHODS: Data extraction was undertaken by one reviewer and checked by a second. Methodological quality was assessed using AMSTAR-2 and Joanna Briggs Institute instruments by two authors independently. Outcomes were categorized and tabulated to assess effectiveness. Qualitative data was analysed using thematic synthesis. RESULTS: Nineteen reviews (163 unique studies) and 11 primary articles with a range of advance care planning definitions and of variable quality were included. Advance care planning was associated with decreased hospitalizations, increased concordance between care received and prior wishes and increased completion of advance care planning documents but quality of primary research was variable. Views of ACP for people with dementia can be clustered around six themes; 1) timing and tailoring, 2) willingness to engage, 3) roles and responsibilities of healthcare professionals, 4) relationships, 5) training and 6) resources needed. Diminishing decision-making capacity over time is a key overarching feature. CONCLUSIONS: Advance care planning is acceptable for people with dementia and their carers and is associated with improved outcomes. Guidelines on which outcomes and which definition to use are necessary, as is research to test different approaches to ACP. Education on topics related to diminishing decision-making capacity is key to optimize advance care planning for people with dementia and their carers.


Assuntos
Planejamento Antecipado de Cuidados/normas , Demência/terapia , Demência/psicologia , Humanos , Cuidados Paliativos/métodos , Cuidados Paliativos/normas
14.
Pediatr Res ; 88(6): 925-933, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32172282

RESUMO

BACKGROUND: Extra-corporeal membrane oxygenation (ECMO) is a life-saving intervention for severe respiratory and cardiac diseases. However, 50% of survivors have abnormal neurologic exams. Current ECMO management is guided by systemic metrics, which may poorly predict cerebral perfusion. Continuous optical monitoring of cerebral hemodynamics during ECMO holds potential to detect risk factors of brain injury such as impaired cerebrovascular autoregulation (CA). METHODS: We conducted daily measurements of microvascular cerebral blood flow (CBF), oxygen saturation, and total hemoglobin concentration using diffuse correlation spectroscopy (DCS) and frequency-domain diffuse optical spectroscopy in nine neonates. We characterize CA utilizing the correlation coefficient (DCSx) between CBF and mean arterial blood pressure (MAP) during ECMO pump flow changes. RESULTS: Average MAP and pump flow levels were weakly correlated with CBF and were not correlated with cerebral oxygen saturation. CA integrity varied between individuals and with time. Systemic measurements of MAP, pulse pressure, and left cardiac dysfunction were not predictive of impaired CA. CONCLUSIONS: Our pilot results suggest that systemic measures alone cannot distinguish impaired CA from intact CA during ECMO. Furthermore, optical neuromonitoring could help determine patient-specific ECMO pump flows for optimal CA integrity, thereby reducing risk of secondary brain injury. IMPACT: Cerebral blood flow and oxygenation are not well predicted by systemic proxies such as ECMO pump flow or blood pressure. Continuous, quantitative, bedside monitoring of cerebral blood flow and oxygenation with optical tools enables new insight into the adequacy of cerebral perfusion during ECMO. A demonstration of hybrid diffuse optical and correlation spectroscopies to continuously measure cerebral blood oxygen saturation and flow in patients on ECMO, enabling assessment of cerebral autoregulation. An observation of poor correlation of cerebral blood flow and oxygenation with systemic mean arterial pressure and ECMO pump flow, suggesting that clinical decision making guided by target values for these surrogates may not be neuroprotective. ~50% of ECMO survivors have long-term neurological deficiencies; continuous monitoring of brain health throughout therapy may reduce these tragically common sequelae through brain-focused adjustment of ECMO parameters.


Assuntos
Encéfalo/fisiopatologia , Circulação Cerebrovascular , Oxigenação por Membrana Extracorpórea/métodos , Hemodinâmica , Microcirculação , Oxigênio/metabolismo , Pressão Sanguínea , Lesões Encefálicas/fisiopatologia , Homeostase/fisiologia , Humanos , Projetos Piloto , Reprodutibilidade dos Testes , Risco , Fatores de Risco , Espalhamento de Radiação , Espectrofotometria , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Resultado do Tratamento
15.
J Cereb Blood Flow Metab ; 40(1): 187-203, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30375917

RESUMO

Management of deep hypothermic (DH) cardiopulmonary bypass (CPB), a critical neuroprotective strategy, currently relies on non-invasive temperature to guide cerebral metabolic suppression during complex cardiac surgery in neonates. Considerable inter-subject variability in temperature response and residual metabolism may contribute to the persisting risk for postoperative neurological injury. To characterize and mitigate this variability, we assess the sufficiency of conventional nasopharyngeal temperature (NPT) guidance, and in the process, validate combined non-invasive frequency-domain diffuse optical spectroscopy (FD-DOS) and diffuse correlation spectroscopy (DCS) for direct measurement of cerebral metabolic rate of oxygen (CMRO2). During CPB, n = 8 neonatal swine underwent cooling from normothermia to 18℃, sustained DH perfusion for 40 min, and then rewarming to simulate cardiac surgery. Continuous non-invasive and invasive measurements of intracranial temperature (ICT) and CMRO2 were acquired. Significant hysteresis (p < 0.001) between cooling and rewarming periods in the NPT versus ICT and NPT versus CMRO2 relationships were found. Resolution of this hysteresis in the ICT versus CMRO2 relationship identified a crucial insufficiency of conventional NPT guidance. Non-invasive CMRO2 temperature coefficients with respect to NPT (Q10 = 2.0) and ICT (Q10 = 2.5) are consistent with previous reports and provide further validation of FD-DOS/DCS CMRO2 monitoring during DH CPB to optimize management.


Assuntos
Temperatura Corporal , Encéfalo/fisiologia , Ponte Cardiopulmonar/métodos , Hipotermia Induzida , Monitorização Fisiológica/métodos , Oxigênio/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Modelos Animais , Perfusão , Análise Espectral/métodos , Suínos
16.
Environ Sci Technol ; 53(21): 12218-12226, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31595747

RESUMO

Polymeric differences of plastic debris were assessed across four compartments of the Main Hawaiian Islands (sea surface, windward beaches, leeward beaches, and seafloor) to better describe sources and fate. Plastic debris pieces (n = 4671) were collected from 11 beaches, three sea surface tows, and three seafloor dives. Fourier transform infrared spectroscopy identified the polymers of 3551 pieces. Significant differences (p < 0.05) in concentration, types, polymer composition, and weathering were found among four compartments. Windward beaches had 1-2 orders of magnitude more plastic pollution (g/m2) than leeward beaches, despite smaller human populations on windward sides. Sea surface and windward beaches were dominated by severely weathered, less dense floating polymers (polyethylene and polypropylene comprised 92.7 and 93.5% on average, respectively, of the total debris mass), while leeward beaches and the seafloor debris consisted of less weathered and more dense sinking polymers (e.g., 41.0 and 44.7% of total mass consisted of the sum of polystyrene, nylon, cellulose acetate, polyethylene terephthalate, and additive-masked debris). These results are some of the first to provide evidence of polymeric stratification in the marine environment and emphasize that the majority of marine debris in Hawaii is floating in from distant sources rather than from Hawaii's residents or tourists.


Assuntos
Monitoramento Ambiental , Polímeros , Praias , Havaí , Humanos , Ilhas , Plásticos , Resíduos
17.
Palliat Med ; 33(7): 726-742, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31057088

RESUMO

BACKGROUND: The European Association for Palliative Care White Paper defined optimal palliative care in dementia based on evidence and expert consensus. Yet, we know little on how to achieve this for people with dementia living and dying at home. AIMS: To examine evidence on home palliative care interventions in dementia, in terms of their effectiveness on end-of-life care outcomes, factors influencing implementation, the extent to which they address the European Association for Palliative Care palliative care domains and evidence gaps. DESIGN: A systematic review of home palliative care interventions in dementia. DATA SOURCES: The review adhered to the PRISMA guidelines and the protocol was registered with PROSPERO (CRD42018093607). We searched four electronic databases up to April 2018 (PubMed, Scopus, Cochrane library and CINAHL) and conducted lateral searches. RESULTS: We retrieved eight relevant studies, none of which was of high quality. The evidence, albeit of generally weak quality, showed the potential benefits of the interventions in improving end-of-life care outcomes, for example, behavioural disturbances. The interventions most commonly focused on optimal symptom management, continuity of care and psychosocial support. Other European Association for Palliative Care domains identified as important in palliative care for people with dementia, for example, prognostication of dying or avoidance of burdensome interventions were under-reported. No direct evidence on facilitators and barriers to implementation was found. CONCLUSIONS: The review highlights the paucity of high-quality dementia-specific research in this area and recommends key areas for future work, for example, the need for process evaluation to identify facilitators and barriers to implementing interventions.


Assuntos
Demência , Serviços de Assistência Domiciliar , Cuidados Paliativos/métodos , Humanos
18.
Mar Pollut Bull ; 138: 70-83, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30660316

RESUMO

Located within the subtropical convergence zone, the Hawaiian archipelago is subject to high debris loads. This paper represents the first study to determine the spatial and temporal trends of floating macro debris quantities and polymer composition within Maui County waters. Ocean surveys were conducted from 2013 to 2017 and collected 2095 debris items of which 90% were plastic. Attempts to categorize items by source resulted in only 6% likely from land, 12% from ocean-based sources, 50% from either land or ocean, and 32% from unknown sources. Results found a multi-step process for debris accumulation, with temporal trends linked to survey day and year and spatial trends linked to ocean processes. High- and low-density polyethylene and polypropylene accounted for the majority of polymer types. The results of this study demonstrate minimal debris in Maui originates from land/local sources, and the importance of baseline data to guide further research and mitigation measures.


Assuntos
Monitoramento Ambiental/métodos , Polímeros/análise , Resíduos/análise , Poluentes Químicos da Água/análise , Havaí , Plásticos/análise
19.
Leukemia ; 33(6): 1400-1410, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30622285

RESUMO

Abnormal metabolism is a fundamental hallmark of cancer and represents a therapeutic opportunity, yet its regulation by oncogenes remains poorly understood. Here, we uncover that JMJD1C, a jumonji C (JmjC)-containing H3K9 demethylase, is a critical regulator of aberrant metabolic processes in homeobox A9 (HOXA9)-dependent acute myeloid leukemia (AML). JMJD1C overexpression increases in vivo cell proliferation and tumorigenicity through demethylase-independent upregulation of a glycolytic and oxidative program, which sustains leukemic cell bioenergetics and contributes to an aggressive AML phenotype in vivo. Targeting JMJD1C-mediated metabolism via pharmacologic inhibition of glycolysis and oxidative phosphorylation led to ATP depletion, induced necrosis/apoptosis and decreased tumor growth in vivo in leukemias co-expressing JMJD1C and HOXA9. The anti-metabolic therapy effectively diminished AML stem/progenitor cells and reduced tumor burden in a primary AML patient-derived xenograft. Our data establish a direct link between drug responses and endogenous expression of JMJD1C and HOXA9 in human AML cell line- and patient-derived xenografts. These findings demonstrate a previously unappreciated role for JMJD1C in counteracting adverse metabolic changes and retaining the metabolic integrity during tumorigenesis, which can be exploited therapeutically.


Assuntos
Regulação Leucêmica da Expressão Gênica , Glicólise , Proteínas de Homeodomínio/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Fosforilação Oxidativa , Oxirredutases N-Desmetilantes/metabolismo , Animais , Proteínas de Homeodomínio/genética , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Leucemia Mieloide Aguda/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Oxirredutases N-Desmetilantes/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Environ Sci Technol ; 52(20): 11535-11544, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30207718

RESUMO

Pelagic Pacific sea turtles eat relatively large quantities of plastic (median 5 g in gut). Using Fourier transform infrared spectroscopy, we identified the polymers ingested by 37 olive ridley, 9 green, and 4 loggerhead turtles caught as bycatch in Hawaii- and American Samoa-based longline fisheries. Unidentifiable samples were analyzed using high-temperature size exclusion chromatography with multiple detectors and/or X-ray photoelectron spectroscopy. Regardless of species differences in dive depths and foraging strategies, ingested plastics were primarily low-density, floating polymers (51% low-density polyethylene (LDPE), 26% polypropylene (PP), 10% unknown polyethylene (PE), and 5% high-density PE collectively). Albeit not statistically significant, deeper diving and deeper captured olive ridley turtles ate proportionally more plastics expected to sink (3.9%) than intermediate-diving green (1.2%) and shallow-diving loggerhead (0.3%) turtles. Spatial, but no sex, size, year, or hook depth differences were observed in polymer composition. LDPE and PP, some of the most produced and least recycled polymers worldwide, account for the largest percentage of plastic eaten by sea turtles in this region. These novel data inform managers about the threat of plastic ingestion to sea turtles and may motivate development of more environmentally friendly practices for plastic production, use, and waste management.


Assuntos
Plásticos , Tartarugas , Animais , Havaí , Polímeros , Resíduos
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