Publications by authors named "Theodore R Weiland"

In the developed world, extreme prematurity is the leading cause of neonatal mortality and morbidity due to a combination of organ immaturity and iatrogenic injury. Until now, efforts to extend gestation using extracorporeal systems have achieved limited success. Here we report the development of a system that incorporates a pumpless oxygenator circuit connected to the fetus of a lamb via an umbilical cord interface that is maintained within a closed 'amniotic fluid' circuit that closely reproduces the environment of the womb.

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Background: Intra-arrest hypothermia induction may provide more benefit than inducing hypothermia after return of spontaneous circulation. However, little is understood about the interaction between patient physiology and hypothermia induction technology choice during ongoing chest compressions.

Methods: After 10 min of untreated ventricular fibrillation, mechanical chest compressions were provided for 60 min (100 CPM, 1.

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Background: Effective cardiopulmonary resuscitation is a critical component of the pre-hospital treatment of cardiac arrest victims. Mechanical chest compression (MCC) devices enable the delivery of MCC waveforms that could not be delivered effectively by hand. While chest compression generated blood flow has been studied for more than 50 years, the relation between sternum kinematics (depth over time) and the resulting blood flow have not been well described.

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Rationale: Although current resuscitation guidelines are rescuer focused, the opportunity exists to develop patient-centered resuscitation strategies that optimize the hemodynamic response of the individual in the hopes to improve survival.

Objectives: To determine if titrating cardiopulmonary resuscitation (CPR) to blood pressure would improve 24-hour survival compared with traditional CPR in a porcine model of asphyxia-associated ventricular fibrillation (VF).

Methods: After 7 minutes of asphyxia, followed by VF, 20 female 3-month-old swine randomly received either blood pressure-targeted care consisting of titration of compression depth to a systolic blood pressure of 100 mm Hg and vasopressors to a coronary perfusion pressure greater than 20 mm Hg (BP care); or optimal American Heart Association Guideline care consisting of depth of 51 mm with standard advanced cardiac life support epinephrine dosing (Guideline care).

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Aim: Advances in cardiopulmonary resuscitation (CPR) have focused on the generation and maintenance of adequate myocardial blood flow to optimize the return of spontaneous circulation and survival. Much of the morbidity associated with cardiac arrest survivors can be attributed to global brain hypoxic ischemic injury. The objective of this study was to compare cerebral physiological variables using a hemodynamic directed resuscitation strategy versus an absolute depth-guided approach in a porcine model of ventricular fibrillation (VF) cardiac arrest.

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Cardiopulmonary resuscitation (CPR) guidelines assume that cardiac arrest victims can be treated with a uniform chest compression (CC) depth and a standardized interval administration of vasopressor drugs. This non-personalized approach does not incorporate a patient's individualized response into ongoing resuscitative efforts. In previously reported porcine models of hypoxic and normoxic ventricular fibrillation (VF), a hemodynamic-directed resuscitation improved short-term survival compared to current practice guidelines.

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Objectives: During cardiopulmonary resuscitation, adequate coronary perfusion pressure is essential for establishing return of spontaneous circulation. Current American Heart Association guidelines recommend standardized interval administration of epinephrine for patients in cardiac arrest. The objective of this study was to compare short-term survival using a hemodynamic directed resuscitation strategy versus chest compression depth-directed cardiopulmonary resuscitation in a porcine model of cardiac arrest.

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All plants contain an unusual class of hemoglobins that display bis-histidyl coordination yet are able to bind exogenous ligands such as oxygen. Structurally homologous hexacoordinate hemoglobins (hxHbs) are also found in animals (neuroglobin and cytoglobin) and some cyanobacteria, where they are thought to play a role in free radical scavenging or ligand sensing. The plant hxHbs can be distinguished from the others because they are only weakly hexcacoordinate in the ferrous state, yet no structural mechanism for regulating hexacoordination has been articulated to account for this behavior.

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Hexacoordinate hemoglobins are a class of proteins that exhibit reversible bis-histidyl coordination of the heme iron while retaining the ability to bind exogenous ligands. One hypothesis for their physiological function is that they scavenge nitric oxide, a reaction that oxidizes the protein and requires reduction of the heme iron to continue. Reduction kinetics of hexacoordinate hemoglobins, including human neuroglobin and cytoglobin, and those from Synechocystis and rice, are compared to myoglobin, soybean leghemoglobin, and several relevant mutant proteins.

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The membrane-active antifungal agent amphotericin B (AmB) is one of the few agents shown to slow the course of prion diseases in animals. Congo Red and other small molecules have been reported to directly inhibit amyloidogenesis in both prion and Alzheimer peptide model systems via specific binding. We propose that it is possible that AmB may act similarly to physically prevent conversion of the largely alpha-helical prion protein (PrP) to the pathological beta-sheet aggregate protease-resistant isoform (PrP(res)) in prion disease and by analogy prevent fibrillization in amyloid diseases.

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