Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 269
Filter
Add more filters

Publication year range
1.
Nature ; 603(7899): 174-179, 2022 03.
Article in English | MEDLINE | ID: mdl-35173332

ABSTRACT

Lassa virus (LASV) is a human pathogen, causing substantial morbidity and mortality1,2. Similar to other Arenaviridae, it presents a class-I spike complex on its surface that facilitates cell entry. The virus's cellular receptor is matriglycan, a linear carbohydrate that is present on α-dystroglycan3,4, but the molecular mechanism that LASV uses to recognize this glycan is unknown. In addition, LASV and other arenaviruses have a unique signal peptide that forms an integral and functionally important part of the mature spike5-8; yet the structure, function and topology of the signal peptide in the membrane remain uncertain9-11. Here we solve the structure of a complete native LASV spike complex, finding that the signal peptide crosses the membrane once and that its amino terminus is located in the extracellular region. Together with a double-sided domain-switching mechanism, the signal peptide helps to stabilize the spike complex in its native conformation. This structure reveals that the LASV spike complex is preloaded with matriglycan, suggesting the mechanism of binding and rationalizing receptor recognition by α-dystroglycan-tropic arenaviruses. This discovery further informs us about the mechanism of viral egress and may facilitate the rational design of novel therapeutics that exploit this binding site.


Subject(s)
Dystroglycans , Lassa virus , Receptors, Virus , Viral Envelope Proteins , Dystroglycans/chemistry , Dystroglycans/metabolism , Humans , Lassa Fever/virology , Lassa virus/chemistry , Lassa virus/metabolism , Protein Conformation , Protein Sorting Signals , Receptors, Virus/chemistry , Receptors, Virus/metabolism , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/metabolism , Virus Internalization
2.
Respir Res ; 24(1): 197, 2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37568148

ABSTRACT

BACKGROUND: Up-regulation of ceramides in pulmonary hypertension (PH), contributing to perturbations in sphingolipid homeostasis and the transition of cells to a senescence state. We assessed the safety, feasibility, and efficiency of acid ceramidase gene transfer in a rodent PH model. METHODS: A model of PH was established by the combination of left pneumonectomy and injection of Sugen toxin. Magnetic resonance imaging and right heart catheterization confirmed development of PH. Animals were subjected to intratracheal administration of synthetic adeno-associated viral vector (Anc80L65) carrying the acid ceramidase (Anc80L65.AC), an empty capsid vector, or saline. Therapeutic efficacy was evaluated 8 weeks after gene delivery. RESULTS: Hemodynamic assessment 4 weeks after PH model the development demonstrated an increase in the mean pulmonary artery pressure to 30.4 ± 2.13 mmHg versus 10.4 ± 1.65 mmHg in sham (p < 0.001), which was consistent with the definition of PH. We documented a significant increase in pulmonary vascular resistance in the saline-treated (6.79 ± 0.85 mm Hg) and empty capsid (6.94 ± 0.47 mm Hg) groups, but not in animals receiving Anc80L65.AC (4.44 ± 0.71 mm Hg, p < 0.001). Morphometric analysis demonstrated an increase in medial wall thickness in control groups in comparison to those treated with acid ceramidase. After acid ceramidase gene delivery, a significant decrease of pro-inflammatory factors, interleukins, and senescence markers was observed. CONCLUSION: Gene delivery of acid ceramidase provided tropism to pulmonary tissue and ameliorated vascular remodeling with right ventricular dysfunction in pulmonary hypertension.


Subject(s)
Hypertension, Pulmonary , Pulmonary Arterial Hypertension , Ventricular Dysfunction, Right , Animals , Hypertension, Pulmonary/genetics , Hypertension, Pulmonary/therapy , Hypertension, Pulmonary/pathology , Acid Ceramidase/genetics , Familial Primary Pulmonary Hypertension , Genetic Therapy , Pulmonary Artery/pathology
3.
Death Stud ; 47(5): 592-599, 2023.
Article in English | MEDLINE | ID: mdl-35993431

ABSTRACT

This cross-sectional study examined the experiences of healthy spouses caring for their partners via the Two-Track Model of Dementia Grief thereby broadening our understanding of the functional and relational aspects of this process. The 122 participating older adults had spouses drawn from four groups: mild to moderate cognitive-impairment; advanced cognitive-impairment; deceased following dementia; and, healthy controls. They completed a battery of self-report measures. Results showed elevated scores on both tracks of the model for all affected groups. Assisting spouses of those living with cognitive-impairment begins with the earliest symptoms of decline and continues after the death of the loved one.


Subject(s)
Dementia , Grief , Humans , Aged , Cross-Sectional Studies , Spouses , Self Report , Caregivers
4.
Inorg Chem ; 61(20): 7970-7979, 2022 May 23.
Article in English | MEDLINE | ID: mdl-35523004

ABSTRACT

Separations based on molecular size (molecular sieving) are a solution for environmental remediation. We have synthesized and characterized two new metal-organic frameworks (MOFs) (Zn2M; M = Zn, Cd) with ultramicropores (<0.7 nm) suitable for molecular sieving. We explore the synthesis of these MOFs and the role that the DMSO/H2O/DMF solvent mixture has on the crystallization process. We further explore the crystallographic data for the DMSO and methanol solvated structures at 273 and 100 K; this not only results in high-quality structural data but also allows us to better understand the structural features at temperatures around the gas adsorption experiments. Structurally, the main difference between the two MOFs is that the central metal in the trimetallic node can be changed from Zn to Cd and that results in a sub-Å change in the size of the pore aperture, but a stark change in the gas adsorption properties. The separation selectivity of the MOF when M = Zn is infinite given the pore aperture of the MOF can accommodate CO2 while N2 and/or CH4 is excluded from entering the pore. Furthermore, due to the size exclusion behavior, the MOF has an adsorption selectivity of 4800:1 CO2/N2 and 5 × 1028:1 CO2/CH4. When M = Cd, the pore aperture of the MOF increases slightly, allowing N2 and CH4 to enter the pore, resulting in a 27.5:1 and a 10.5:1 adsorption selectivity, respectively; this is akin to UiO-66, a MOF that is not able to function as a molecular sieve for these gases. The data delineate how subtle sub-Å changes to the pore aperture of a framework can drastically affect both the adsorption selectivity and separation selectivity.

5.
Am J Perinatol ; 2022 May 17.
Article in English | MEDLINE | ID: mdl-35292943

ABSTRACT

Understanding the role of stress in pregnancy and its consequences is important, particularly given documented associations between maternal stress and preterm birth and other pathological outcomes. Physical and psychological stressors can elicit the same biological responses, known as biological strain. Chronic stressors, like poverty and racism (race-based discriminatory treatment), may create a legacy or trajectory of biological strain that no amount of coping can relieve in the absence of larger-scale socio-behavioral or societal changes. An integrative approach that takes into consideration simultaneously social and biological determinants of stress may provide the best insights into the risk of preterm birth. The most successful computational approaches and the most predictive machine-learning models are likely to be those that combine information about the stressors and the biological strain (for example, as measured by different omics) experienced during pregnancy.

6.
Omega (Westport) ; : 302228221142632, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36428253

ABSTRACT

The aim of the present research was to study the interplay of Attachment Theory and the Two-Track Model of Dementia Grief. To examine the research hypotheses, a cross-sectional study was designed and included 122 participants (Mean age = 72.77) drawn from four groups: spouses of people living with mild to moderate cognitive impairment, spouses of people living with advanced cognitive impairment, widowed spouses of deceased dementia patients, and a control group. Participants completed a battery of self-report questionnaires. Results showed that secure attachment constitutes a significant protective factor with regard to bio-psycho-social symptomatology (Track I) as well as difficulties in the relational bond with the spouse and grief over their deterioration (Track II). The results of the research support integrating attachment-based insights into clinical work with spouses coping with the losses accompanying cognitive decline and the grief processes that are operant in these losses.

7.
Circulation ; 141(11): 916-930, 2020 03 17.
Article in English | MEDLINE | ID: mdl-31992066

ABSTRACT

BACKGROUND: Sphingolipids have recently emerged as a biomarker of recurrence and mortality after myocardial infarction (MI). The increased ceramide levels in mammalian heart tissues during acute MI, as demonstrated by several groups, is associated with higher cell death rates in the left ventricle and deteriorated cardiac function. Ceramidase, the only enzyme known to hydrolyze proapoptotic ceramide, generates sphingosine, which is then phosphorylated by sphingosine kinase to produce the prosurvival molecule sphingosine-1-phosphate. We hypothesized that Acid Ceramidase (AC) overexpression would counteract the negative effects of elevated ceramide and promote cell survival, thereby providing cardioprotection after MI. METHODS: We performed transcriptomic, sphingolipid, and protein analyses to evaluate sphingolipid metabolism and signaling post-MI. We investigated the effect of altering ceramide metabolism through a loss (chemical inhibitors) or gain (modified mRNA [modRNA]) of AC function post hypoxia or MI. RESULTS: We found that several genes involved in de novo ceramide synthesis were upregulated and that ceramide (C16, C20, C20:1, and C24) levels had significantly increased 24 hours after MI. AC inhibition after hypoxia or MI resulted in reduced AC activity and increased cell death. By contrast, enhancing AC activity via AC modRNA treatment increased cell survival after hypoxia or MI. AC modRNA-treated mice had significantly better heart function, longer survival, and smaller scar size than control mice 28 days post-MI. We attributed the improvement in heart function post-MI after AC modRNA delivery to decreased ceramide levels, lower cell death rates, and changes in the composition of the immune cell population in the left ventricle manifested by lowered abundance of proinflammatory detrimental neutrophils. CONCLUSIONS: Our findings suggest that transiently altering sphingolipid metabolism through AC overexpression is sufficient and necessary to induce cardioprotection post-MI, thereby highlighting the therapeutic potential of AC modRNA in ischemic heart disease.


Subject(s)
Acid Ceramidase/physiology , Genetic Therapy , Hypoxia/metabolism , Myocardial Infarction/metabolism , RNA, Messenger/therapeutic use , Sphingolipids/metabolism , Acid Ceramidase/antagonists & inhibitors , Acid Ceramidase/genetics , Animals , Animals, Newborn , Apoptosis , Ceramides/metabolism , Cicatrix/pathology , Embryoid Bodies , Enzyme Induction , Female , Humans , Hypoxia/etiology , Hypoxia/pathology , Induced Pluripotent Stem Cells/metabolism , Inflammation , Male , Mice , Myocardial Infarction/complications , Myocardial Infarction/drug therapy , Myocardial Infarction/pathology , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA, Messenger/pharmacology , Rats , Rats, Sprague-Dawley , Recombinant Proteins/metabolism , Transfection , Up-Regulation
8.
Am J Physiol Endocrinol Metab ; 321(1): E90-E104, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34029162

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of disorders ranging from hepatic steatosis [excessive accumulation of triglycerides (TG)] to nonalcoholic steatohepatitis, which can progress to cirrhosis and hepatocellular carcinoma. The molecular pathogenesis of steatosis and progression to more severe NAFLD remains unclear. Obesity and aging, two principal risk factors for NAFLD, are associated with a hyperadrenergic state. ß-Adrenergic responsiveness in liver increases in animal models of obesity and aging, and in both is linked to increased hepatic expression of ß2-adrenergic receptors (ß2-ARs). We previously showed that in aging rodents intracellular signaling from elevated hepatic levels of ß2-ARs may contribute to liver steatosis. In this study we demonstrate that injection of formoterol, a highly selective ß2-AR agonist, to mice acutely results in hepatic TG accumulation. Further, we have sought to define the intrahepatic mechanisms underlying ß2-AR mediated steatosis by investigating changes in hepatic expression and cellular localization of enzymes, transcription factors, and coactivators involved in processes of lipid accrual and disposition-and also functional aspects thereof-in livers of formoterol-treated animals. Our results suggest that ß2-AR activation by formoterol leads to increased hepatic TG synthesis and de novo lipogenesis, increased but incomplete ß-oxidation of fatty acids with accumulation of potentially toxic long-chain acylcarnitine intermediates, and reduced TG secretion-all previously invoked as contributors to fatty liver disease. Experiments are ongoing to determine whether sustained activation of hepatic ß2-AR signaling by formoterol might be utilized to model fatty liver changes occurring in hyperadrenergic states of obesity and aging, and thereby identify novel molecular targets for the prevention or treatment of NAFLD.NEW & NOTEWORTHY Results of our study suggest that ß2-adrenergic receptor (ß2-AR) activation by agonist formoterol leads to increased hepatic TG synthesis and de novo lipogenesis, incomplete ß-oxidation of fatty acids with accumulation of long-chain acylcarnitine intermediates, and reduced TG secretion. These findings may, for the first time, implicate a role for ß2-AR responsive dysregulation of hepatic lipid metabolism in the pathogenetic processes underlying NAFLD in hyperadrenergic states such as obesity and aging.


Subject(s)
Adrenergic beta-2 Receptor Agonists/pharmacology , Fatty Liver/chemically induced , Non-alcoholic Fatty Liver Disease/physiopathology , Receptors, Adrenergic, beta-2/physiology , Animals , Carnitine/analogs & derivatives , Carnitine/analysis , Formoterol Fumarate/pharmacology , Gene Expression/drug effects , Hepatic Stellate Cells , Lipid Metabolism/drug effects , Lipid Metabolism/physiology , Lipogenesis/genetics , Liver/chemistry , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/chemically induced , Phosphatidate Phosphatase/analysis , Triglycerides/biosynthesis
9.
Coord Chem Rev ; 4292021 Feb 15.
Article in English | MEDLINE | ID: mdl-33678810

ABSTRACT

Porphyrins are important molecules widely found in nature in the form of enzyme active sites and visible light absorption units. Recent interest in using these functional molecules as building blocks for the construction of metal-organic frameworks (MOFs) have rapidly increased due to the ease in which the locations of, and the distances between, the porphyrin units can be controlled in these porous crystalline materials. Porphyrin-based MOFs with atomically precise structures provide an ideal platform for the investigation of their structure-function relationships in the solid state without compromising accessibility to the inherent properties of the porphyrin building blocks. This review will provide a historical overview of the development and applications of porphyrin-based MOFs from early studies focused on design and structures, to recent efforts on their utilization in biomimetic catalysis, photocatalysis, electrocatalysis, sensing, and biomedical applications.

10.
Phys Rev Lett ; 126(5): 051102, 2021 Feb 05.
Article in English | MEDLINE | ID: mdl-33605747

ABSTRACT

The future space mission LISA will observe a wealth of gravitational-wave sources at millihertz frequencies. Of these, the extreme-mass-ratio inspirals of compact objects into massive black holes are the only sources that combine the challenges of strong-field complexity with that of long-lived signals. Such signals are found and characterized by comparing them against a large number of accurate waveform templates during data analysis, but the rapid generation of templates is hindered by computing the ∼10^{3}-10^{5} harmonic modes in a fully relativistic waveform. We use order-reduction and deep-learning techniques to derive a global fit for the ≈4000 modes in the special case of an eccentric Schwarzschild orbit, and implement the fit in a complete waveform framework with hardware acceleration. Our high-fidelity waveforms can be generated in under 1 s, and achieve a mismatch of ≲5×10^{-4} against reference waveforms that take ≳10^{4} times longer. This marks the first time that analysis-length waveforms with full harmonic content can be produced on timescales useful for direct implementation in LISA analysis algorithms.

11.
Mol Ther ; 28(2): 394-410, 2020 02 05.
Article in English | MEDLINE | ID: mdl-31879190

ABSTRACT

Inhibition of pulmonary fibrosis (PF) by restoring sarco/endoplasmic reticulum calcium ATPase 2a isoform (SERCA2a) expression using targeted gene therapy may be a potentially powerful new treatment approach for PF. Here, we found that SERCA2a expression was significantly decreased in lung samples from patients with PF and in the bleomycin (BLM) mouse model of PF. In the BLM-induced PF model, intratracheal aerosolized adeno-associated virus serotype 1 (AAV1) encoding for human SERCA2a (AAV1.hSERCA2a) reduces lung fibrosis and associated vascular remodeling. SERCA2a gene therapy also decreases right ventricular pressure and hypertrophy in both prevention and curative protocols. In vitro, we observed that SERCA2a overexpression inhibits fibroblast proliferation, migration, and fibroblast-to-myofibroblast transition induced by transforming growth factor ß (TGF-ß1). Thus, pro-fibrotic gene expression is prevented by blocking nuclear factor κB (NF-κB)/interleukin-6 (IL-6)-induced signal transducer and activator of transcription 3 (STAT3) activation. This effect is signaled toward an inhibitory mechanism of small mother against decapentaplegic (SMAD)/TGF-ß signaling through the repression of OTU deubiquitinase, ubiquitin aldehyde binding 1 (OTUB1) and Forkhead box M1 (FOXM1). Interestingly, this cross-inhibition leads to an increase of SKI and SnoN expression, an auto-inhibitory feedback loop of TGF-ß signaling. Collectively, our results demonstrate that SERCA2a gene transfer attenuates bleomycin (BLM)-induced PF by blocking the STAT3/FOXM1 pathway and promoting the SNON/SKI Axis. Thus, SERCA2a gene therapy may be a potential therapeutic target for PF.


Subject(s)
Dependovirus/genetics , Genetic Therapy , Genetic Vectors/genetics , Pulmonary Fibrosis/genetics , Pulmonary Fibrosis/metabolism , Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics , Signal Transduction , Animals , DNA-Binding Proteins/metabolism , Disease Models, Animal , Fibroblasts/metabolism , Forkhead Box Protein M1/metabolism , Gene Expression , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Proto-Oncogene Proteins/metabolism , Pulmonary Fibrosis/therapy , STAT3 Transcription Factor/metabolism
12.
J Clin Pharm Ther ; 46(1): 114-120, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32949161

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Hypertension (HTN) and chronic kidney disease (CKD) are recognized as silent killers because they are asymptomatic conditions that contribute to the burden of multiple comorbidities. The achievement of a blood pressure (BP) goal can dramatically reduce the risks of CKD. In this study, we aimed to assess the effectiveness of pharmacist intervention on BP control in patients with CKD and evaluate the usefulness of home-based BP telemonitoring. METHODS: The terms "chronic kidney disease," "pharmacist," "BP" and "randomized controlled trial (RCT)" were used five databases to search for information regarding pharmacist intervention on BP control in patients with CKD. The inclusion criteria were as follows: (a) studies for adult patients with uncontrolled HTN and (b) studies with adequate data for meta-analysis. The primary outcome was an evaluation of achievement of BP goal in patients with CKD. The secondary outcome was usefulness of home-based BP telemonitoring by pharmacists in patients with CKD. RESULTS AND DISCUSSION: Six RCTs were identified and included in the meta-analysis with a total of 2573 patients (mean age 66.0 years and 63.9% male). Pharmacist interventions resulted in significantly better BP control vs usual care (OR = 1.53, 95% CI = 1.15-2.04, P < .01). Pharmacist interventions using home-based BP telemonitoring were significantly superior to control/usual care (OR = 2.03, 95% CI = 1.49-2.77, P < .01), whereas pharmacist interventions without home-based BP telemonitoring did not significantly improve BP control compared to that with control/usual care (OR = 1.30, 95% CI = 0.97-1.75, P = .08). Home-based BP telemonitoring supported team-based care for HTN in these studies. In addition, patient self-monitoring with telemedicine devices might enhance patients' abilities to manage their condition by pharmacist instruction. WHAT IS NEW AND CONCLUSION: The findings of this meta-analysis showed that pharmacist interventions with home-based BP telemonitoring improve BP control among adult patients with CKD.


Subject(s)
Antihypertensive Agents/therapeutic use , Hypertension/drug therapy , Pharmaceutical Services , Renal Insufficiency, Chronic , Telemedicine , Antihypertensive Agents/administration & dosage , Humans , Randomized Controlled Trials as Topic
13.
J Card Surg ; 36(9): 3155-3162, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34056766

ABSTRACT

BACKGROUND: Traditionally, wire cerclage closure has been used to reapproximate the sternum after cardiac surgery. Recent evidence suggests that rigid sternal fixation may reduce the risk of wound complications. The aim of this study was to analyze our 10-year experience with longitudinal rigid sternal fixation (LRSF) for prevention and treatment of wound complications in high-risk patients. METHODS: We reviewed data from cardiac surgical database of patients who underwent LRSF, and compared their outcomes with conventional wire cerclage closure (CWS). Among these 319 patients were designated as having high-risk for the development of deep wound complications and received primary LRSF (treatment group). We matched their outcomes with 319 patients who met indications for LRSF however, underwent standard closure with CWC (control group). RESULTS: Both groups were comparable regarding preoperative and intraoperative variables. The benefit observed among matched patients who had undergone LRSF was largely driven by a decreased rate of deep wound infections (0.63% vs. 3.45% vs., p < .01), 30-day mortality (1.57% vs. 5.96%) and hospital length (8.2 vs. 11.7 days) p < .05, respectively. A multivariate logistic regression analysis found four independent risk factors for the development of sternal dehiscence. Sternal healing evaluated by computerized tomography scan using 6-point scale at 3 months after surgery was superior in LRSF patients. Pain scores were significantly lower in LRSF patients as well. CONCLUSIONS: In patients with an increased risk for sternal instability and wound infections after cardiac surgery, sternal reconstruction using LRSF is an effective technique to stabilize sternum for preventive and treatment purposes.


Subject(s)
Cardiac Surgical Procedures , Sternotomy , Bone Plates , Humans , Sternotomy/adverse effects , Sternum/surgery , Surgical Wound Dehiscence/prevention & control , Surgical Wound Infection/prevention & control , Treatment Outcome
14.
Int J Mol Sci ; 22(17)2021 Aug 24.
Article in English | MEDLINE | ID: mdl-34502015

ABSTRACT

Pulmonary arterial hypertension (PAH) is a devastating lung disease characterized by the progressive obstruction of the distal pulmonary arteries (PA). Structural and functional alteration of pulmonary artery smooth muscle cells (PASMC) and endothelial cells (PAEC) contributes to PA wall remodeling and vascular resistance, which may lead to maladaptive right ventricular (RV) failure and, ultimately, death. Here, we found that decreased expression of sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) in the lung samples of PAH patients was associated with the down-regulation of bone morphogenetic protein receptor type 2 (BMPR2) and the activation of signal transducer and activator of transcription 3 (STAT3). Our results showed that the antiproliferative properties of SERCA2a are mediated through the STAT3/BMPR2 pathway. At the molecular level, transcriptome analysis of PASMCs co-overexpressing SERCA2a and BMPR2 identified STAT3 amongst the most highly regulated transcription factors. Using a specific siRNA and a potent pharmacological STAT3 inhibitor (STAT3i, HJC0152), we found that SERCA2a potentiated BMPR2 expression by repressing STAT3 activity in PASMCs and PAECs. In vivo, we used a validated and efficient model of severe PAH induced by unilateral left pneumonectomy combined with monocrotaline (PNT/MCT) to further evaluate the therapeutic potential of single and combination therapies using adeno-associated virus (AAV) technology and a STAT3i. We found that intratracheal delivery of AAV1 encoding SERCA2 or BMPR2 alone or STAT3i was sufficient to reduce the mean PA pressure and vascular remodeling while improving RV systolic pressures, RV ejection fraction, and cardiac remodeling. Interestingly, we found that combined therapy of AAV1.hSERCA2a with AAV1.hBMPR2 or STAT3i enhanced the beneficial effects of SERCA2a. Finally, we used cardiac magnetic resonance imaging to measure RV function and found that therapies using AAV1.hSERCA2a alone or combined with STAT3i significantly inhibited RV structural and functional changes in PNT/MCT-induced PAH. In conclusion, our study demonstrated that combination therapies using SERCA2a gene transfer with a STAT3 inhibitor could represent a new promising therapeutic alternative to inhibit PAH and to restore BMPR2 expression by limiting STAT3 activity.


Subject(s)
Bone Morphogenetic Protein Receptors, Type II/genetics , Lung/drug effects , Pulmonary Arterial Hypertension/drug therapy , RNA, Small Interfering/pharmacology , STAT3 Transcription Factor/antagonists & inhibitors , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Animals , Cells, Cultured , Gene Expression Profiling , Gene Expression Regulation , Genetic Therapy , Humans , Lung/metabolism , Lung/pathology , Pulmonary Arterial Hypertension/genetics , Pulmonary Arterial Hypertension/metabolism , Pulmonary Arterial Hypertension/pathology , RNA, Small Interfering/therapeutic use , Rats , Rats, Sprague-Dawley , STAT3 Transcription Factor/genetics , Vascular Remodeling/drug effects
15.
Exp Astron (Dordr) ; 51(3): 1427-1440, 2021.
Article in English | MEDLINE | ID: mdl-34720416

ABSTRACT

Since 2015 the gravitational-wave observations of LIGO and Virgo have transformed our understanding of compact-object binaries. In the years to come, ground-based gravitational-wave observatories such as LIGO, Virgo, and their successors will increase in sensitivity, discovering thousands of stellar-mass binaries. In the 2030s, the space-based LISA will provide gravitational-wave observations of massive black holes binaries. Between the ∼ 10 -103 Hz band of ground-based observatories and the ∼ 1 0 - 4 -10- 1 Hz band of LISA lies the uncharted decihertz gravitational-wave band. We propose a Decihertz Observatory to study this frequency range, and to complement observations made by other detectors. Decihertz observatories are well suited to observation of intermediate-mass ( ∼ 1 0 2 -104 M ⊙) black holes; they will be able to detect stellar-mass binaries days to years before they merge, providing early warning of nearby binary neutron star mergers and measurements of the eccentricity of binary black holes, and they will enable new tests of general relativity and the Standard Model of particle physics. Here we summarise how a Decihertz Observatory could provide unique insights into how black holes form and evolve across cosmic time, improve prospects for both multimessenger astronomy and multiband gravitational-wave astronomy, and enable new probes of gravity, particle physics and cosmology.

16.
FASEB J ; 33(8): 9008-9016, 2019 08.
Article in English | MEDLINE | ID: mdl-31042404

ABSTRACT

Na+/H+ exchanger regulatory factor 1 (NHERF1; also known as ezrin-radixin-moesin-binding phosphoprotein 50) is a PSD-95, disc large, zona occludens-1 adapter that acts as a scaffold for signaling complexes and cytoskeletal-plasma membrane interactions. NHERF1 is crucial to ß-2-adrenoceptor (ß2AR)-mediated activation of cystic fibrosis transmembrane conductance regulator (CFTR) in epithelial cells, and NHERF1 has been proposed to mediate the recycling of internalized ß2AR back to the cell membrane. In the current study, we assessed the role of NHERF1 in regulating cAMP-mediated signaling and immunomodulatory functions in airway smooth muscle (ASM). NHERF1 knockdown attenuated the induction of (protein kinase A) phospho-vasodilator-stimulated phosphoprotein (p-VASP) by isoproterenol (ISO), prostaglandin E2 (PGE2), or forskolin (FSK) as well as the induction of p-heat shock protein 20 after 4 h of stimulation with ISO and FSK. NHERF1 knockdown fully abrogated the ISO-, PGE2-, and FSK-induced IL-6 gene expression and cytokine production without affecting cAMP-mediated phosphodiesterase 4D (PDE4D) gene expression, phospho-cAMP response element-binding protein (p-CREB), and cAMP response element (CRE)-Luc, or PDGF-induced cyclin D1 expression. Interestingly, NHERF1 knockdown prevented ISO-induced chromatin-binding of the transcription factor CCAAT-enhancer-binding protein-ß (c/EBPß). c/EBPß knockdown almost completely abrogated the cAMP-mediated IL-6 but not PDE4D gene expression. The differential regulation of cAMP-induced signaling and gene expression in our study indicates a role for NHERF1 in the compartmentalization of cAMP signaling in ASM.-Pera, T., Tompkins, E., Katz, M., Wang, B., Deshpande, D. A., Weinman, E. J., Penn, R. B. Specificity of NHERF1 regulation of GPCR signaling and function in human airway smooth muscle.


Subject(s)
Muscle, Smooth/metabolism , Phosphoproteins/metabolism , Receptors, G-Protein-Coupled/metabolism , Respiratory System/metabolism , Sodium-Hydrogen Exchangers/metabolism , CCAAT-Enhancer-Binding Protein-beta/metabolism , Cyclic AMP/metabolism , Cyclin D1/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Gene Expression Regulation , Gene Knockdown Techniques , Humans , Muscle, Smooth/immunology , Muscle, Smooth/physiology , Phosphoproteins/antagonists & inhibitors , Phosphoproteins/genetics , Respiratory Physiological Phenomena , Respiratory System/immunology , Signal Transduction , Sodium-Hydrogen Exchangers/antagonists & inhibitors , Sodium-Hydrogen Exchangers/genetics
17.
J Vasc Interv Radiol ; 31(6): 986-992, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32414569

ABSTRACT

PURPOSE: To assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications. MATERIALS AND METHODS: Six academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11-94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1-5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications. RESULTS: Balloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred. CONCLUSIONS: Balloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).


Subject(s)
Arteriovenous Malformations/therapy , Balloon Occlusion , Neoplasms/therapy , Polyvinyls/administration & dosage , Vascular Diseases/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Arteriovenous Malformations/diagnostic imaging , Balloon Occlusion/adverse effects , Child , Feasibility Studies , Female , Humans , Male , Middle Aged , Neoplasms/diagnostic imaging , Neoplasms/pathology , Polyvinyls/adverse effects , Retrospective Studies , Treatment Outcome , United States , Vascular Diseases/diagnostic imaging , Young Adult
18.
Environ Sci Technol ; 54(21): 13509-13516, 2020 11 03.
Article in English | MEDLINE | ID: mdl-33058682

ABSTRACT

The billions of tons of mineral dust released into the atmosphere each year provide an important surface for reaction with gas-phase pollutants. These reactions, which are often enhanced in the presence of light, can change both the gas-phase composition of the atmosphere and the composition and properties of the dust itself. Because dust contains titanium-rich grains, studies of dust photochemistry have largely employed commercial titanium dioxide as a proxy for its photochemically active fraction; to date, however, the validity of this model system has not been empirically determined. Here, for the first time, we directly investigate the photochemistry of the complement of natural titanium-containing minerals most relevant to mineral dust, including anatase, rutile, ilmenite, titanite, and several titanium-bearing species. Using ozone as a model gas-phase pollutant, we show that titanium-containing minerals other than titanium dioxide can also photocatalyze trace gas uptake, that samples of the same mineral phase can display very different reactivity, and that prediction of dust photoreactivity based on elemental/mineralogical analysis and/or light-absorbing properties is challenging. Together, these results show that the photochemistry of atmospheric dust is both richer and more complex than previously considered, and imply that a full understanding of the scope and impact of dust-mediated processes will require the community to engage with this complexity via the study of ambient mineral dust samples from diverse source regions.


Subject(s)
Dust , Titanium , Atmosphere , Dust/analysis , Minerals , Photochemistry
19.
Heart Surg Forum ; 23(1): E058-E060, 2020 02 25.
Article in English | MEDLINE | ID: mdl-32118544

ABSTRACT

In recent decades, new information has arisen regarding sternal healing and extended indications for using rigid plate fixation in patients during cardio-thoracic procedures. Three randomized controlled multicenter clinical trials recently demonstrated positive results after rigid plate fixation, including reduced sternal complications and decreased length of hospital stay. However, redo-sternotomy after sternal reconstruction utilizing rigid fixation has not been previously delineated in surgical literature. This case highlights the technical challenges of performing a median sternotomy for cardiac surgery after sternal reconstruction with bilateral longitudinal plating.


Subject(s)
Bone Plates , Coronary Artery Bypass, Off-Pump/methods , Coronary Disease/surgery , Osteoporosis/complications , Reoperation , Sternotomy/methods , Aged , Chest Pain/etiology , Chest Pain/surgery , Fractures, Bone/complications , Fractures, Bone/surgery , Humans , Male , Pain, Intractable/etiology , Pain, Intractable/surgery , Sternum/injuries , Treatment Outcome , Wound Closure Techniques , Wounds, Nonpenetrating/complications , Wounds, Nonpenetrating/surgery
20.
Heart Fail Rev ; 24(5): 759-777, 2019 09.
Article in English | MEDLINE | ID: mdl-30903356

ABSTRACT

Rodent surgical animal models of heart failure (HF) are critically important for understanding the proof of principle of the cellular alterations underlying the development of the disease as well as evaluating therapeutics. Robust, reproducible rodent models are a prerequisite to the development of pharmacological and molecular strategies for the treatment of HF in patients. Due to the absence of standardized guidelines regarding surgical technique and clear criteria for HF progression in rats, objectivity is compromised. Scientific publications in rats rarely fully disclose the actual surgical details, and technical and physiological challenges. This lack of reporting is one of the main reasons that the outcomes specified in similar studies are highly variable and associated with unnecessary loss of animals, compromising scientific assessment. This review details rat circulatory and coronary arteries anatomy, the surgical details of rat models that recreate the HF phenotype of myocardial infarction, ischemia/reperfusion, left and right ventricular pressure, and volume overload states, and summarizes the technical and physiological challenges of creating HF. The purpose of this article is to help investigators understand the underlying issues of current HF models in order to reduce variable results and ensure successful, reproducible models of HF.


Subject(s)
Cardiac Surgical Procedures/standards , Disease Models, Animal , Heart Failure/physiopathology , Rats/physiology , Rats/surgery , Animals , Humans , Myocardial Infarction/physiopathology , Myocardial Reperfusion Injury/physiopathology , Rats/anatomy & histology , Reproducibility of Results , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Right/physiopathology
SELECTION OF CITATIONS
SEARCH DETAIL