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1.
J Struct Biol ; 216(3): 108105, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852682

RESUMO

Human serum albumin (HSA) is the most prevalent plasma protein in the human body, accounting for 60 % of the total plasma protein. HSA plays a major pharmacokinetic function, serving as a facilitator in the distribution of endobiotics and xenobiotics within the organism. In this paper we report the cryoEM structures of HSA in the apo form and in complex with two ligands (salicylic acid and teniposide) at a resolution of 3.5, 3.7 and 3.4 Å, respectively. We expand upon previously published work and further demonstrate that sub-4 Å maps of ∼60 kDa proteins can be routinely obtained using a 200 kV microscope, employing standard workflows. Most importantly, these maps allowed for the identification of small molecule ligands, emphasizing the practical applicability of this methodology and providing a starting point for subsequent computational modeling and in silico optimization.

2.
Am J Physiol Lung Cell Mol Physiol ; 326(3): L330-L343, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38252635

RESUMO

Extremely preterm infants are often exposed to long durations of mechanical ventilation to facilitate gas exchange, resulting in ventilation-induced lung injury (VILI). New lung protective strategies utilizing noninvasive ventilation or low tidal volumes are now common but have not reduced rates of bronchopulmonary dysplasia. We aimed to determine the effect of 24 h of low tidal volume ventilation on the immature lung by ventilating preterm fetal sheep in utero. Preterm fetal sheep at 110 ± 1(SD) days' gestation underwent sterile surgery for instrumentation with a tracheal loop to enable in utero mechanical ventilation (IUV). At 112 ± 1 days' gestation, fetuses received either in utero mechanical ventilation (IUV, n = 10) targeting 3-5 mL/kg for 24 h, or no ventilation (CONT, n = 9). At necropsy, fetal lungs were collected to assess molecular and histological markers of lung inflammation and injury. IUV significantly increased lung mRNA expression of interleukin (IL)-1ß, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF) compared with CONT, and increased surfactant protein (SP)-A1, SP-B, and SP-C mRNA expression compared with CONT. IUV produced modest structural changes to the airways, including reduced parenchymal collagen and myofibroblast density. IUV increased pulmonary arteriole thickness compared with CONT but did not alter overall elastin or collagen content within the vasculature. In utero ventilation of an extremely preterm lung, even at low tidal volumes, induces lung inflammation and injury to the airways and vasculature. In utero ventilation may be an important model to isolate the confounding mechanisms of VILI to develop effective therapies for preterm infants requiring prolonged respiratory support.NEW & NOTEWORTHY Preterm infants often require prolonged respiratory support, but the relative contribution of ventilation to the development of lung injury is difficult to isolate. In utero mechanical ventilation allows for mechanistic investigations into ventilation-induced lung injury without confounding factors associated with sustaining extremely preterm lambs ex utero. Twenty-four hours of in utero ventilation, even at low tidal volumes, increased lung inflammation and surfactant protein expression and produced structural changes to the lung parenchyma and vasculature.


Assuntos
Pneumonia , Lesão Pulmonar Induzida por Ventilação Mecânica , Humanos , Recém-Nascido , Ovinos , Animais , Lactente Extremamente Prematuro , Pulmão/metabolismo , Feto/metabolismo , Respiração Artificial/efeitos adversos , Respiração Artificial/métodos , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Colágeno/metabolismo , Pneumonia/patologia , Tensoativos/metabolismo , RNA Mensageiro/metabolismo
3.
J Neuroinflammation ; 21(1): 142, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807204

RESUMO

BACKGROUND: Intrauterine inflammation is considered a major cause of brain injury in preterm infants, leading to long-term neurodevelopmental deficits. A potential contributor to this brain injury is dysregulation of neurovascular coupling. We have shown that intrauterine inflammation induced by intra-amniotic lipopolysaccharide (LPS) in preterm lambs, and postnatal dopamine administration, disrupts neurovascular coupling and the functional cerebral haemodynamic responses, potentially leading to impaired brain development. In this study, we aimed to characterise the structural changes of the neurovascular unit following intrauterine LPS exposure and postnatal dopamine administration in the brain of preterm lambs using cellular and molecular analyses. METHODS: At 119-120 days of gestation (term = 147 days), LPS was administered into the amniotic sac in pregnant ewes. At 126-7 days of gestation, the LPS-exposed lambs were delivered, ventilated and given either a continuous intravenous infusion of dopamine at 10 µg/kg/min or isovolumetric vehicle solution for 90 min (LPS, n = 6; LPSDA, n = 6). Control preterm lambs not exposed to LPS were also administered vehicle or dopamine (CTL, n = 9; CTLDA, n = 7). Post-mortem brain tissue was collected 3-4 h after birth for immunohistochemistry and RT-qPCR analysis of components of the neurovascular unit. RESULTS: LPS exposure increased vascular leakage in the presence of increased vascular density and remodelling with increased astrocyte "end feet" vessel coverage, together with downregulated mRNA levels of the tight junction proteins Claudin-1 and Occludin. Dopamine administration decreased vessel density and size, decreased endothelial glucose transporter, reduced neuronal dendritic coverage, increased cell proliferation within vessel walls, and increased pericyte vascular coverage particularly within the cortical and deep grey matter. Dopamine also downregulated VEGFA and Occludin tight junction mRNA, and upregulated dopamine receptor DRD1 and oxidative protein (NOX1, SOD3) mRNA levels. Dopamine administration following LPS exposure did not exacerbate any effects induced by LPS. CONCLUSION: LPS exposure and dopamine administration independently alters the neurovascular unit in the preterm brain. Alterations to the neurovascular unit may predispose the developing brain to further injury.


Assuntos
Animais Recém-Nascidos , Dopamina , Lipopolissacarídeos , Animais , Dopamina/metabolismo , Ovinos , Feminino , Lipopolissacarídeos/toxicidade , Gravidez , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/patologia
4.
J Neuroinflammation ; 21(1): 121, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720368

RESUMO

BACKGROUND: Umbilical cord blood (UCB) cells are a promising treatment for preterm brain injury. Access to allogeneic sources of UCB cells offer the potential for early administration to optimise their therapeutic capacities. As preterm infants often require ventilatory support, which can contribute to preterm brain injury, we investigated the efficacy of early UCB cell administration following ventilation to reduce white matter inflammation and injury. METHODS: Preterm fetal sheep (0.85 gestation) were randomly allocated to no ventilation (SHAM; n = 5) or 15 min ex utero high tidal volume ventilation. One hour following ventilation, fetuses were randomly allocated to i.v. administration of saline (VENT; n = 7) or allogeneic term-derived UCB cells (24.5 ± 5.0 million cells/kg; VENT + UCB; n = 7). Twenty-four hours after ventilation, lambs were delivered for magnetic resonance imaging and post-mortem brain tissue collected. Arterial plasma was collected throughout the experiment for cytokine analyses. To further investigate the results from the in vivo study, mononuclear cells (MNCs) isolated from human UCB were subjected to in vitro cytokine-spiked culture medium (TNFα and/or IFNγ; 10 ng/mL; n = 3/group) for 16 h then supernatant and cells collected for protein and mRNA assessments respectively. RESULTS: In VENT + UCB lambs, systemic IFNγ levels increased and by 24 h, there was white matter neuroglial activation, vascular damage, reduced oligodendrocytes, and increased average, radial and mean diffusivity compared to VENT and SHAM. No evidence of white matter inflammation or injury was present in VENT lambs, except for mRNA downregulation of OCLN and CLDN1 compared to SHAM. In vitro, MNCs subjected to TNFα and/or IFNγ displayed both pro- and anti-inflammatory characteristics indicated by changes in cytokine (IL-18 & IL-10) and growth factor (BDNF & VEGF) gene and protein expression compared to controls. CONCLUSIONS: UCB cells administered early after brief high tidal volume ventilation in preterm fetal sheep causes white matter injury, and the mechanisms underlying these changes are likely dysregulated responses of the UCB cells to the degree of injury/inflammation already present. If immunomodulatory therapies such as UCB cells are to become a therapeutic strategy for preterm brain injury, especially after ventilation, our study suggests that the inflammatory state of the preterm infant should be considered when timing UCB cells administration.


Assuntos
Volume de Ventilação Pulmonar , Animais , Ovinos , Feminino , Humanos , Volume de Ventilação Pulmonar/fisiologia , Sangue Fetal/citologia , Gravidez , Citocinas/metabolismo , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Respiração Artificial/métodos , Respiração Artificial/efeitos adversos , Animais Recém-Nascidos
5.
Int J Mol Sci ; 25(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38674110

RESUMO

Membrane proteins constitute about 20% of the human proteome and play crucial roles in cellular functions. However, a complete understanding of their structure and function is limited by their hydrophobic nature, which poses significant challenges in purification and stabilization. Detergents, essential in the isolation process, risk destabilizing or altering the proteins' native conformations, thus affecting stability and functionality. This study leverages single-particle cryo-electron microscopy to elucidate the structural nuances of membrane proteins, focusing on the SLAC1 bacterial homolog from Haemophilus influenzae (HiTehA) purified with diverse detergents, including n-dodecyl ß-D-maltopyranoside (DDM), glycodiosgenin (GDN), ß-D-octyl-glucoside (OG), and lauryl maltose neopentyl glycol (LMNG). This research not only contributes to the understanding of membrane protein structures but also addresses detergent effects on protein purification. By showcasing that the overall structural integrity of the channel is preserved, our study underscores the intricate interplay between proteins and detergents, offering insightful implications for drug design and membrane biology.


Assuntos
Proteínas de Bactérias , Microscopia Crioeletrônica , Detergentes , Haemophilus influenzae , Microscopia Crioeletrônica/métodos , Haemophilus influenzae/ultraestrutura , Haemophilus influenzae/química , Proteínas de Bactérias/química , Proteínas de Bactérias/ultraestrutura , Detergentes/química , Microscopia Eletrônica de Transmissão/métodos , Proteínas de Membrana/química , Proteínas de Membrana/ultraestrutura , Proteínas de Membrana/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-39088356

RESUMO

Virtual reality (VR) has emerged as a nonpharmacological adjuvant to manage acute and chronic pain symptoms. The goal of this survey study was to determine the acceptability of VR among chronic pain participants hailing from distressed and prosperous neighborhoods in the state of Maryland. We hypothesized that pain severity and interference vary in groups experiencing health disparities, potentially influencing VR's acceptability. From March 11 to March 15, 2020, we surveyed a cohort of clinically phenotyped participants suffering from chronic orofacial pain. Participants were asked to express their willingness to participate in a longitudinal VR study and their expectation of pain relief from using VR. Seventy out of 350 participants with chronic pain completed the survey (response rate: 20%). There was no difference in the likelihood of responding to the survey based on their neighborhood distress. Among survey respondents and nonrespondents, similar proportions of participants were from distressed neighborhoods. Among the respondents, 63 (90%) and 59 (84.3%) were willing to participate and expected to experience pain relief from the VR intervention, respectively. Age, sex, race, neighborhood distress, severity of pain, and prior VR experience did not influence willingness to participate in the VR trial or the expectations of VR-induced improvement. These findings suggest that VR as an adjuvant intervention is potentially accepted by chronic pain participants, irrespective of neighborhood-level social determinants of health.

7.
Food Sci Nutr ; 12(4): 2679-2691, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628185

RESUMO

Soursop (Annona muricata L.) fruit tea is a health-beneficial product that promotes economic development and addresses the issue of excessive agricultural waste. Prolonging the shelf-life of soursop fruit tea has been of scientific interest currently. This study evaluated the effects of three types of packaging materials of soursop fruit tea (e.g., paper, paper-combined Polyetylen (PE), and aluminum-combined PE) and different storage temperatures (5, 15, 30, and 45°C) on various product characteristics, total polyphenol content (TPC), total flavonoid content (TFC), total ascorbic acid (TAA), and 2,2-diphenyl-1-picryl hydrazyl (DPPH)/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging capacity during 4 weeks of storage. The results revealed that the sample stored in aluminum-combined PE packaging at 30°C retained most of the product's characteristics and nutritional values. This was evidenced by the moisture content of 2.49%, TAA of 3.9 ± 1.4 mg/100 g dry weight, TPC of 12.89 ± 0.47 mgGAE/g, TFC of 0.54 ± 0.004 mgQE/g, DPPH scavenging activity of 4.06 ± 0.02 mgAA/g, and ABTS scavenging activity of 13.34 ± 0.32 mgAA/g. Additionally, the microbiological quality of the sample met the standard of TCVN 9740:2013. Overall, the study highlights the importance of packaging materials and storage temperatures to maintain the nutritional quality of soursop fruit tea. It provides valuable insights into the suitable storage conditions for preserving the quality and health-promoting effects of this product.

8.
Front Cell Neurosci ; 18: 1397658, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962513

RESUMO

Background: Intrauterine inflammation and the requirement for mechanical ventilation independently increase the risk of perinatal brain injury and adverse neurodevelopmental outcomes. We aimed to investigate the effects of mechanical ventilation for 24 h, with and without prior exposure to intrauterine inflammation, on markers of brain inflammation and injury in the preterm sheep brain. Methods: Chronically instrumented fetal sheep at ~115 days of gestation were randomly allocated to receive a single intratracheal dose of 1 mg lipopolysaccharide (LPS) or isovolumetric saline, then further randomly allocated 1 h after to receive mechanical ventilation with room air or no mechanical ventilation (unventilated control + saline [UVC, n = 7]; in utero mechanical ventilation + saline [VENT, n = 8], unventilated control + intratracheal LPS [UVC + LPS, n = 7]; in utero ventilation + intratracheal LPS [VENT + LPS, n = 7]). Serial fetal blood and plasma samples were collected throughout the experimental protocol for assessment of blood biochemistry and plasma interleukin (IL)-6 levels. After 24 h of mechanical ventilation, fetal brains were collected for RT-qPCR and immunohistochemical analyses. Results: LPS exposure increased numbers of microglia and upregulated pro-inflammatory related genes within the cortical gray matter (GM) and subcortical white matter (SCWM) (pLPS < 0.05). Mechanical ventilation alone increased astrocytic cell density in the periventricular white matter (PVWM) (pVENT = 0.03) but had no effect on pro-inflammatory gene expression. The combination of ventilation and LPS increased plasma IL-6 levels (p < 0.02 vs. UVC and VENT groups), and exacerbated expression of pro-inflammatory-related genes (IL1ß, TLR4, PTGS2, CXCL10) and microglial density (p < 0.05 vs. VENT). Conclusion: This study demonstrates that 24 h of mechanical ventilation after exposure to intrauterine inflammation increased markers of systemic and brain inflammation and led to the upregulation of pro-inflammatory genes in the white matter. We conclude that 24 h of mechanical ventilation following intrauterine inflammation may precondition the preterm brain toward being more susceptible to inflammation-induced injury.

9.
Nat Commun ; 15(1): 6367, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112449

RESUMO

Male sex, early life chemical exposure and the brain aromatase enzyme have been implicated in autism spectrum disorder (ASD). In the Barwon Infant Study birth cohort (n = 1074), higher prenatal maternal bisphenol A (BPA) levels are associated with higher ASD symptoms at age 2 and diagnosis at age 9 only in males with low aromatase genetic pathway activity scores. Higher prenatal BPA levels are predictive of higher cord blood methylation across the CYP19A1 brain promoter I.f region (P = 0.009) and aromatase gene methylation mediates (P = 0.01) the link between higher prenatal BPA and brain-derived neurotrophic factor methylation, with independent cohort replication. BPA suppressed aromatase expression in vitro and in vivo. Male mice exposed to mid-gestation BPA or with aromatase knockout have ASD-like behaviors with structural and functional brain changes. 10-hydroxy-2-decenoic acid (10HDA), an estrogenic fatty acid alleviated these features and reversed detrimental neurodevelopmental gene expression. Here we demonstrate that prenatal BPA exposure is associated with impaired brain aromatase function and ASD-related behaviors and brain abnormalities in males that may be reversible through postnatal 10HDA intervention.


Assuntos
Aromatase , Transtorno do Espectro Autista , Compostos Benzidrílicos , Encéfalo , Metilação de DNA , Camundongos Knockout , Fenóis , Efeitos Tardios da Exposição Pré-Natal , Animais , Aromatase/metabolismo , Aromatase/genética , Masculino , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/induzido quimicamente , Compostos Benzidrílicos/toxicidade , Feminino , Fenóis/toxicidade , Gravidez , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Camundongos , Humanos , Metilação de DNA/efeitos dos fármacos , Fenótipo , Modelos Animais de Doenças , Regiões Promotoras Genéticas , Pré-Escolar
10.
Am J Med Open ; 10: 100047, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39035245

RESUMO

Objective: The social determinants of health (SDoH) account for 80%-90% of modifiable contributors to health outcomes for chronic diseases such as heart failure. Knowledge gaps exist on how SDoH influences hospitalization rates in women with heart failure. Our aim was to evaluate the relationship between the baseline SDoH status of women with heart failure with subsequent all-cause and cardiovascular hospitalization. Methods: This is a prospective observational longitudinal cohort study of women diagnosed with heart failure with 6-month follow-up. The subjects completed SDoH assessment by the Institute of Medicine. Monthly follow-ups were performed to assess for hospitalization events. Results: A total of 92 patients with at least 1 follow-up clinic visit were included. The mean age was 66 ± 15 years and 80% had nonischemic cardiomyopathy as the etiology of heart failure. New York Heart Association (NYHA) Classifications I-II were the most common (n = 66, 71.8%). In total, 51 patients (55.4%) had overall high-risk SDoH (4 or more SDoH domains at risk). By the 6-month follow-up, 22 (23.9%) patients were hospitalized for any cause; 8 patients (8.7%) were hospitalized for cardiovascular causes. There were no deaths. In multivariate logistic regression analysis, the high-risk SDoH group had a higher odds ratio for all-cause hospitalization (OR 5.31, 95% CI 1.59-17.73). In addition, Kansas City Cardiomyopathy Questionnaire 12-item (KCCQ-12) scores, surrogate for quality of life, were worse in the high-risk SDoH group. Conclusion: SDoH adversely impacts hospitalizations and quality of life in women with heart failure. Future efforts for screening and interventions should evaluate the SDoH at all levels, including the individual health care provider, institutional, and national levels.

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