J Trauma Acute Care Surg
March 2025
Background: Cell-free hemoglobin (CFH) and free heme are potent mediators of endotheliopathy and organ injury in sepsis, but their roles in other hemolytic pathologies are not well-defined. A prime example is trauma where early hemolysis may initiate damage and predict outcome. Here, we investigated the presence of plasma CFH, heme, and their major scavengers after traumatic injury.
View Article and Find Full Text PDFObjective: The aim of the study was to compare the stiffness and cyclic fatigue of locking compression plate constructs from three manufacturers, DePuy Synthes (DPS), Knight Benedikt (KB), and Provet Veterinary Instrumentation (Vi), under cyclic torsion.
Methods: The constructs of DPS, KB, and Vi were assembled by fixing a 10-hole 3.5-mm stainless steel locking compression plate 1 mm away from a validated bone model with a fracture gap of 47 mm.
Background: Impaired kidney function is frequently observed in patients following cardiopulmonary bypass (CPB). Our group has previously linked blood transfusion to acute declines in S-nitroso haemoglobin (SNO-Hb; the main regulator of tissue oxygen delivery), reductions in intraoperative renal blood flow, and postoperative kidney dysfunction. While not all CPB patients receive blood, kidney injury is still common.
View Article and Find Full Text PDFBackground: Concerns remain over the long-term safety of vascular endothelial growth factor (VEGF) inhibitors to treat retinopathy of prematurity (ROP). RAINBOW is an open label randomised trial comparing intravitreal ranibizumab (in 0.2 mg and 0.
View Article and Find Full Text PDFAcyl-coenzyme A (acyl-CoA) species are cofactors for numerous enzymes that acylate thousands of proteins. Here, we describe an enzyme that uses S-nitroso-CoA (SNO-CoA) as its cofactor to S-nitrosylate multiple proteins (SNO-CoA-assisted nitrosylase, SCAN). Separate domains in SCAN mediate SNO-CoA and substrate binding, allowing SCAN to selectively catalyze SNO transfer from SNO-CoA to SCAN to multiple protein targets, including the insulin receptor (INSR) and insulin receptor substrate 1 (IRS1).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2023
S-Nitrosohemoglobin (SNO-Hb) is unique among vasodilators in coupling blood flow to tissue oxygen requirements, thus fulfilling an essential function of the microcirculation. However, this essential physiology has not been tested clinically. Reactive hyperemia following limb ischemia/occlusion is a standard clinical test of microcirculatory function, which has been ascribed to endothelial nitric oxide (NO).
View Article and Find Full Text PDFJt Comm J Qual Patient Saf
January 2023
Background: Although unnecessary blood component transfusions are costly and pose substantial patient risks, the extent of unnecessary blood use in a community hospital setting has not been systematically measured.
Methods: A 15-hospital observational analysis was performed using comprehensive retrospective review. Approximately 100 encounters (x¯ = 103.
The β-adrenergic receptor (βAR), a prototypic G-protein-coupled receptor (GPCR), is a powerful driver of bronchorelaxation, but the effectiveness of β-agonist drugs in asthma is limited by desensitization and tachyphylaxis. We find that during activation, the βAR is modified by S-nitrosylation, which is essential for both classic desensitization by PKA as well as desensitization of NO-based signaling that mediates bronchorelaxation. Strikingly, S-nitrosylation alone can drive βAR internalization in the absence of traditional agonist.
View Article and Find Full Text PDFCurrent human donor care protocols following death by neurologic criteria (DNC) can stabilize macro-hemodynamic parameters but have minimal ability to preserve systemic blood flow and microvascular oxygen delivery. S-nitrosylated hemoglobin (SNO-Hb) within red blood cells (RBCs) is the main regulator of tissue oxygenation (StO). Based on various pre-clinical studies, we hypothesized that brain death (BD) would decrease post-mortem SNO-Hb levels to negatively-impact StO and reduce organ yields.
View Article and Find Full Text PDFPurpose: To study the time course of retinopathy of prematurity (ROP) regression and reactivation after treatment with intravitreal ranibizumab or laser in the ranibizumab compared with laser therapy for the treatment of infants born prematurely with ROP trial.
Design: Post hoc analysis of a randomized, clinical trial.
Subjects: A total of 225 infants (448 eyes) were randomized to ranibizumab 0.
Antioxidants (Basel)
September 2021
Thiol-NO adducts such as -nitrosoglutathione (GSNO) are endogenous bronchodilators in human airways. Decreased airway -nitrosothiol concentrations are associated with asthma. Nitric oxide (NO), a breakdown product of GSNO, is measured in exhaled breath as a biomarker in asthma; an elevated fraction of expired NO (F) is associated with asthmatic airway inflammation.
View Article and Find Full Text PDFBackground: Intravitreal injection of vascular endothelial growth factor (VEGF) inhibitors is increasingly used to treat retinopathy of prematurity (ROP) in the absence of evidence about long-term efficacy or safety. In this prespecified interim analysis of the RAINBOW extension study, we aimed to prospectively assess outcomes at age 2 years.
Methods: RAINBOW was an open-label, randomised trial that compared intravitreal ranibizumab (at 0·1 mg and 0·2 mg doses) with laser therapy for the treatment of ROP in very low birthweight infants (<1500 g).
Ophthalmology
October 2021
Purpose: The International Classification of Retinopathy of Prematurity is a consensus statement that creates a standard nomenclature for classification of retinopathy of prematurity (ROP). It was initially published in 1984, expanded in 1987, and revisited in 2005. This article presents a third revision, the International Classification of Retinopathy of Prematurity, Third Edition (ICROP3), which is now required because of challenges such as: (1) concerns about subjectivity in critical elements of disease classification; (2) innovations in ophthalmic imaging; (3) novel pharmacologic therapies (e.
View Article and Find Full Text PDFTraumatic brain injury (TBI) is the largest non-genetic, non-aging related risk factor for Alzheimer's disease (AD). We report here that TBI induces tau acetylation (ac-tau) at sites acetylated also in human AD brain. This is mediated by S-nitrosylated-GAPDH, which simultaneously inactivates Sirtuin1 deacetylase and activates p300/CBP acetyltransferase, increasing neuronal ac-tau.
View Article and Find Full Text PDFChronic neurodegeneration in survivors of traumatic brain injury (TBI) is a major cause of morbidity, with no effective therapies to mitigate this progressive and debilitating form of nerve cell death. Here, we report that pharmacologic restoration of the blood-brain barrier (BBB), 12 mo after murine TBI, is associated with arrested axonal neurodegeneration and cognitive recovery, benefits that persisted for months after treatment cessation. Recovery was achieved by 30 d of once-daily administration of P7C3-A20, a compound that stabilizes cellular energy levels.
View Article and Find Full Text PDFPurpose: To develop a population pharmacokinetic (PK) model for intravitreal ranibizumab in infants with retinopathy of prematurity (ROP) and assess plasma free vascular endothelial growth factor (VEGF) pharmacodynamics (PD).
Methods: The RAnibizumab compared with laser therapy for the treatment of INfants BOrn prematurely With retinopathy of prematurity (RAINBOW) trial enrolled 225 infants to receive a bilateral intravitreal injection of ranibizumab 0.1 mg, ranibizumab 0.
Red blood cell (RBC)-mediated vasodilation plays an important role in oxygen delivery. This occurs through hemoglobin actions, at least in significant part, to convert heme-bound nitric oxide (NO) (in tense [T]/deoxygenated-state hemoglobin) into vasodilator S-nitrosothiol (SNO) (in relaxed [R]/oxygenated-state hemoglobin), convey SNO through the bloodstream, and release it into tissues to increase blood flow. The coupling of hemoglobin R/T state allostery, both to NO conversion into SNO and to SNO release (along with oxygen), under hypoxia supports the model of a three-gas respiratory cycle (O/NO/CO).
View Article and Find Full Text PDFObjective: To determine if addition of the S-nitrosylating agent ethyl nitrite (ENO) to the preservation solution can improve perfusion parameters in pumped human kidneys.
Background: A significant percentage of actively stored kidneys experience elevations in resistance and decreases in flow rate during the ex vivo storage period. Preclinical work indicates that renal status after brain death is negatively impacted by inflammation and reduced perfusion-processes regulated by protein S-nitrosylation.
A continuous supply of oxygen is essential for the survival of multicellular organisms. The understanding of how this supply is regulated in the microvasculature has evolved from viewing erythrocytes (red blood cells [RBCs]) as passive carriers of oxygen to recognizing the complex interplay between Hb (hemoglobin) and oxygen, carbon dioxide, and nitric oxide-the three-gas respiratory cycle-that insures adequate oxygen and nutrient delivery to meet local metabolic demand. In this context, it is blood flow and not blood oxygen content that is the main driver of tissue oxygenation by RBCs.
View Article and Find Full Text PDFBackground: Despite increasing worldwide use of anti-vascular endothelial growth factor agents for treatment of retinopathy of prematurity (ROP), there are few data on their ocular efficacy, the appropriate drug and dose, the need for retreatment, and the possibility of long-term systemic effects. We evaluated the efficacy and safety of intravitreal ranibizumab compared with laser therapy in treatment of ROP.
Methods: This randomised, open-label, superiority multicentre, three-arm, parallel group trial was done in 87 neonatal and ophthalmic centres in 26 countries.
J Pediatr Ophthalmol Strabismus
March 2019