Publications by authors named "Nathan D Putz"

Article Synopsis
  • - The alveolar epithelium has a protective layer called the glycocalyx, which gets damaged during conditions like acute respiratory distress syndrome (ARDS) and influenza A infection, leading to increased lung injury by making the alveolar-capillary barrier more permeable.
  • - In the study, researchers tested the impact of a matrix metalloproteinase (MMP) inhibitor called Ilomastat (ILO) on glycocalyx shedding and lung injury in mouse models infected with influenza A, measuring various indicators over several days.
  • - Results showed that IAV infection caused significant glycocalyx shedding, but treatment with ILO reduced the shedding by 36% and lung injury by 40%, while also lowering the viral load
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Article Synopsis
  • Cell-free hemoglobin (CFH) in the lungs of patients with acute respiratory distress syndrome (ARDS) causes inflammation and lung injury, but the mechanisms are not fully understood.
  • Researchers hypothesized that Toll-like receptor 4 (TLR4) plays a role in mediating the inflammatory response to CFH.
  • Their findings showed that mice lacking TLR4 had less inflammation and lung permeability, indicating that TLR4 signaling activates key inflammatory pathways after CFH exposure.
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There are no effective targeted therapies to treat acute respiratory distress syndrome (ARDS). Recently, the commonly used diabetes and obesity medications, glucagon-like peptide-1 (GLP-1) receptor agonists, have been found to have anti-inflammatory properties. We, therefore, hypothesized that liraglutide pretreatment would attenuate murine sepsis-induced acute lung injury (ALI).

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Sepsis is a devastating disease with high morbidity and mortality and no specific treatments. The pathophysiology of sepsis involves a hyperinflammatory response and release of damage-associated molecular patterns (DAMPs), including adenosine triphosphate (ATP), from activated and dying cells. Purinergic receptors activated by ATP have gained attention for their roles in sepsis, which can be pro- or anti-inflammatory depending on the context.

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Women have higher prevalence of asthma compared with men. In asthma, allergic airway inflammation is initiated by IL-33 signaling through ST2, leading to increased IL-4, IL-5, and IL-13 production and eosinophil infiltration. Foxp3+ Tregs suppress and ST2+ Tregs promote allergic airway inflammation.

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Mouse models of acute lung injury (ALI) have been instrumental for studies of the biological underpinnings of lung inflammation and permeability, but murine models of sepsis generate minimal lung injury. Our goal was to create a murine sepsis model of ALI that reflects the inflammation, lung edema, histological abnormalities, and physiological dysfunction that characterize ALI. Using a cecal slurry (CS) model of polymicrobial abdominal sepsis and exposure to hyperoxia (95%), we systematically varied the timing and dose of the CS injection, fluids and antibiotics, and dose of hyperoxia.

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Vitamin C (ascorbate, ASC) is a critical antioxidant in the body with specific roles in the brain. Despite a recent interest in vitamin C therapies for critical care medicine, little is known about vitamin C regulation during acute inflammation and critical illnesses such as sepsis. Using a cecal slurry (CS) model of sepsis in mice, we determined ASC and inflammatory changes in the brain following the initial treatment.

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Article Synopsis
  • Elevated endothelial permeability during sepsis is linked to organ dysfunction and mortality, but the mechanisms behind this increase remain unclear.
  • Previous research indicated that cell-free hemoglobin (CFH) is found at high levels in sepsis patients and can increase lung microvascular permeability.
  • This study showed that CFH worsens outcomes in a mouse model of sepsis, contributing to higher mortality and inflammation while suggesting that CFH may be a potential target for treatment.
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Acute respiratory distress syndrome (ARDS) is an inflammatory lung disorder that frequently complicates critical illness and commonly occurs in sepsis. Although numerous clinical and environmental risk factors exist, not all patients with risk factors develop ARDS, raising the possibility of genetic underpinnings for ARDS susceptibility. We have previously reported that circulating cell-free hemoglobin (CFH) is elevated during sepsis, and higher levels predict worse outcomes.

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Acute kidney injury is a common complication of severe sepsis and contributes to high mortality. The molecular mechanisms of acute kidney injury during sepsis are not fully understood. Because hemoproteins, including myoglobin and hemoglobin, are known to mediate kidney injury during rhabdomyolysis, we hypothesized that cell-free hemoglobin (CFH) would exacerbate acute kidney injury during sepsis.

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  • Acute respiratory distress syndrome (ARDS) leads to severe lung inflammation and low oxygen levels, posing a risk of death, making effective strategies crucial for improving patient outcomes.
  • The study assessed GBT1118, a compound designed to enhance hemoglobin's oxygen-carrying capacity, in a murine model of lung injury, showing it significantly reduced mortality and improved oxygen saturation compared to untreated controls.
  • GBT1118 treatments did not negatively impact lung tissue integrity or inflammation levels, suggesting that increasing oxygen affinity of hemoglobin could be a promising therapy for hypoxemia in ARDS patients.
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Patients with the acute respiratory distress syndrome (ARDS) have elevated levels of cell-free hemoglobin (CFH) in the air space, but the contribution of CFH to the pathogenesis of acute lung injury is unknown. In the present study, we demonstrate that levels of CFH in the air space correlate with measures of alveolar-capillary barrier dysfunction in humans with ARDS (r = 0.89, P < 0.

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Tissue factor (TF) initiates the extrinsic coagulation cascade in response to tissue injury, leading to local fibrin deposition. Low levels of TF in mice are associated with increased severity of acute lung injury (ALI) after intratracheal LPS administration. However, the cellular sources of the TF required for protection from LPS-induced ALI remain unknown.

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