Frederick V. Ramsey

Bcl-2–associated athanogene 3 protects the heart from ischemia/reperfusion injury

Bcl-2-associated athanogene 3 (BAG3) is an evolutionarily conserved protein expressed at high levels in the heart and the vasculature and in many cancers. While altered BAG3 expression has been associated with cardiac dysfunction, its role in ischemia/reperfusion (I/R) is unknown. To test the hypothesis that BAG3 protects the heart from reperfusion injury, in vivo cardiac function was measured in hearts infected with either recombinant adeno-associated virus serotype 9-expressing (rAAV9-expressing) BAG3 or GFP and subjected to I/R. To elucidate molecular mechanisms by which BAG3 protects against I/R injury, neonatal mouse ventricular cardiomyocytes (NMVCs) in which BAG3 levels were modified by adenovirus expressing (Ad-expressing) BAG3 or siBAG3 were exposed to hypoxia/reoxygenation (H/R). H/R significantly reduced NMVC BAG3 levels, which were associated with enhanced expression of apoptosis markers, decreased expression of autophagy markers, and reduced autophagy flux. The deleterious effects of H/R on apoptosis and autophagy were recapitulated by knockdown of BAG3 with Ad-siBAG3 and were rescued by Ad-BAG3. In vivo, treatment of mice with rAAV9-BAG3 prior to I/R significantly decreased infarct size and improved left ventricular function when compared with mice receiving rAAV9-GFP and improved markers of autophagy and apoptosis. These findings suggest that BAG3 may provide a therapeutic target in patients undergoing reperfusion after myocardial infarction.

Adeno-Associated Virus Serotype 9–Driven Expression of BAG3 Improves Left Ventricular Function in Murine Hearts With Left Ventricular Dysfunction Secondary to a Myocardial Infarction

Visual Abstract

Intragastric Meal Distribution during Gastric Emptying Scintigraphy for Assessment of Fundic Accommodation: Correlation with Symptoms of Gastroparesis

Impaired fundic accommodation (FA) limits fundic relaxation and the ability to act as a reservoir for food. Assessing intragastric meal distribution (IMD) during gastric emptying scintigraphy (GES) allows for a simple measure of FA. The 3 goals of this study were to evaluate trained readers’ (nuclear medicine and radiology physicians) visual assessments of FA from solid-meal GES; develop software to quantify GES IMD; and correlate symptoms of gastroparesis with IMD and gastric emptying. Methods: After training to achieve a consensus interpretation of GES FA, 4 readers interpreted FA in 148 GES studies from normal volunteers and patients. Mixture distribution and κ-agreement analyses were used to assess reader consistency and agreement of scoring of FA. Semiautomated software was used to quantify IMD (ratio of gastric counts in the proximal stomach to those in the total stomach) at 0, 1, 2, 3, and 4 h after ingestion of a meal. Receiver-operating-characteristic analysis was performed to optimize the diagnosis of abnormal IMD at 0 min (IMD0) with impaired FA. IMD0, GES, water load testing, and symptoms were then compared in 177 patients with symptoms of gastroparesis. Results: Reader pairwise weighted κ-values for the visual assessment of FA averaged 0.43 (moderate agreement) for normal FA versus impaired FA. Readers achieved 84.0% consensus and 85.8% reproducibility in assessing impaired FA. IMD0 based on the division of the stomach into proximal and distal halves averaged 0.809 (SD, 0.083) for normal FA and 0.447 (SD, 0.132) (P < 0.01) for impaired FA. On the basis of receiver-operating-characteristic analysis, the optimal cutoff for IMD0 discrimination of normal FA from impaired FA was 0.568 (sensitivity, 86.7%; specificity, 91.7%). Of 177 patients with symptoms of gastroparesis, 129 (72.9%) had delayed gastric emptying; 25 (14.1%) had abnormal IMD0. Low IMD0 (impaired FA) was associated with increased early satiety (P = 0.02). Conclusion: FA can be assessed visually during routine GES with moderate agreement and high reader consistency. Visual and quantitative assessments of FA during GES can yield additional information on gastric motility to help explain patients’ symptoms.

Administration of intravenous antibiotics in patients with open fractures is dependent on emergency room triaging

Background Recent literature has demonstrated that emergent administration of antibiotics is perhaps more critical than even emergent debridement. Most recent studies recommend patients receive antibiotics no later than 1 hour after injury to prevent infection. The objective of this study is to evaluate the time to antibiotic administration after patients with open fractures arrive to a trauma center depending on triaging team. Methods A retrospective study at a level 1 Trauma center from January 2013 to March 2015 where 117 patients with open fractures were evaluated. Patients who presented with open fractures of the extremities or pelvis were considered. Subjects were identified using Current Procedural Terminology (CPT) codes. Patients aged 18 and older were analyzed for Gustilo type, antibiotics administered in the emergency room (ER), presence of an antibiotic allergy, post-operative antibiotic regimen and number of debridements, among others. Additionally, whether a patient was triaged by ER doctors or trauma surgeons (and made a trauma activation) was evaluated. Outcome measurements included time to intravenous (IV) antibiotic administration and time to surgical debridement. Results Patients received IV cefazolin a median of 17 minutes after arrival. Eighty-five patients who were made trauma activations received cefazolin 14 minutes after arrival while 24 non-trauma patients received cefazolin 53 minutes after arrival (p = <0.0001). The median time to gentamicin administration for all patients was 180 minutes. Patients not upgraded to a trauma received gentamicin 263 minutes after arrival, while patients upgraded received gentamicin 176 minutes after arrival. There was no statistically significant difference between the timing to cefazolin or gentamicin based on Gustilo type. Conclusions Overall, patients that arrive at our institution with open fractures receive IV cefazolin significantly faster when trauma surgeons evaluate the patient. Additionally, delays in gentamicin administration are demonstrated in both triaging groups. This is due to the fact that cefazolin is stocked in the hospital ER, while gentamicin is commonly not due to weight-based dosing requirements precluding a standard dose. Improvements can be made to antibiotic administration of non-trauma patients and those requiring gentamicin via improved education and awareness of open fractures.

Association of Variants in BAG3 With Cardiomyopathy Outcomes in African American Individuals

Importance The prevalence of nonischemic dilated cardiomyopathy (DCM) is greater in individuals of African ancestry than in individuals of European ancestry. However, little is known about whether the difference in prevalence or outcomes is associated with functional genetic variants. Objective We hypothesized that Bcl2-associated anthanogene 3 (BAG3) genetic variants were associated with outcomes in individuals of African ancestry with DCM. Design This multicohort study of the BAG3 genotype in patients of African ancestry with dilated cardiomyopathy uses DNA obtained from African American individuals enrolled in 3 clinical studies: the Genetic Risk Assessment of African Americans With Heart Failure (GRAHF) study; the Intervention in Myocarditis and Acute Cardiomyopathy Trial-2 (IMAC-2) study; and the Genetic Risk Assessment of Cardiac Events (GRACE) study. Samples of DNA were also acquired from the left ventricular myocardium of patients of African ancestry who underwent heart transplant at the University of Colorado and University of Pittsburgh. Main Outcomes and Measures The primary end points were the prevalence of BAG3 mutations in African American individuals and event-free survival in participants harboring functional BAG3 mutations. Results Four BAG3 genetic variants were identified; these were expressed in 42 of 402 African American individuals (10.4%) with nonischemic heart failure and 9 of 107 African American individuals (8.4%) with ischemic heart failure but were not present in a reference population of European ancestry (P < .001). The variants included 2 nonsynonymous single-nucleotide variants; 1 three-nucleotide in-frame insertion; and 2 single-nucleotide variants that were linked in cis. The presence of BAG3 variants was associated with a nearly 2-fold (hazard ratio, 1.97 [95% CI, 1.19-3.24]; P = .01) increase in cardiac events in carriers compared with noncarriers. Transfection of transformed adult human ventricular myocytes with plasmids expressing the 4 variants demonstrated that each variant caused an increase in apoptosis and a decrease in autophagy when samples were subjected to the stress of hypoxia-reoxygenation. Conclusions and Relevance This study demonstrates that genetic variants in BAG3 found almost exclusively in individuals of African ancestry were not causative of disease but were associated with a negative outcome in patients with a dilated cardiomyopathy through modulation of the function of BAG3. The results emphasize the importance of biological differences in causing phenotypic variance across diverse patient populations, the need to include diverse populations in genetic cohorts, and the importance of determining the pathogenicity of genetic variants.

Patient Satisfaction in the Preoperative Period: Preparing for Hand Surgery:

Background: The potential impact of the number and type of preoperative encounters on satisfaction rates prior to elective surgical procedures is unclear, specifically scheduling and medical clearance encounters. Methods: Questionnaires investigating satisfaction with the preoperative process were collected for 200 patients presenting for elective hand surgery. The number of telephone, surgeon, and medical clearance encounters were recorded, and satisfaction was determined for each type based on a 4-category Likert scale. All patients 18 years or older were included, while only patients providing incomplete questionnaires were excluded. Outcome data were assessed for associations between different encounter totals or types and satisfaction rates. Results: Among 200 patients, 197 completed the questionnaire and were included. Overall satisfaction with the preoperative process was 92.9%, with only 3% of patients dissatisfied. There was a significant association between satisfaction and the number of telephone and total encounters. Satisfaction fell below 90% after 4 or more telephone calls (66.6%, P = 0.005) and 5 or more total encounters (80%, P = 0.008). When considered individually, there was no significant association between satisfaction and the number of surgeon (P = 0.267) or medical office encounters (P = 0.087), or a patient’s perceived health status (P = 0.14). Conclusions: Greater than 3 telephone or 4 total encounters significantly decreases patient satisfaction, while surgeon and medical office visits are not associated with satisfaction rates when considered individually. This suggests the number, not the type, of preoperative encounters impact satisfaction and highlight the importance of efficient communication between patients and providers.

Why Not Life and Limb? Vasopressor Use in Intensive Care Unit Patients the Cause of Acute Limb Ischemia

Background: Acute limb ischemia (ALI) of the upper extremity is a rare yet severe condition in intensive care unit (ICU) patients that generally leads to amputation. The aim of this study is to determine risk factors for development of upper extremity limb ischemia in ICU patients requiring vasopressor support. Methods: This is a retrospective study conducted from 2010 to 2015. Patients who received vasopressors during ICU admission were considered for the study. Patients were identified via Current Procedural Terminology (CPT) billing codes. ALI patients were matched to control patients based on diagnosis and Acute Physiology and Chronic Health Evaluation II score. Days on pressors, number of pressors, total doses, and level of ischemia were recorded. Primary end point was doses, types, and days on vasopressors. Secondary end point was level of ALI. Results: Patients in the ALI group were more likely to be started on a higher number of different types of pressors (2.6 vs 1.3 pressors). ALI patients received pressors for 8.5 days compared with 1.6 days in control patients, and received 12.8 doses compared with 3.0 doses in control patients. In addition, vasopressors with alpha-adrenergic activity were more likely to be used in the ALI group. Level of ischemia was not linked to any of the tested variables. Conclusion: Patients admitted to the ICU are more likely to sustain an acute ischemic event of an upper extremity with more vasopressor usage. Patients who received alpha-adrenergic activating vasopressors were more likely to sustain limb ischemia. When discoloration of an extremity is detected, patients should receive counteractive treatments in an effort to salvage the extremity and prevent function loss.

Activation and polarization of circulating monocytes in severe chronic obstructive pulmonary disease

BackgroundThe ability of circulating monocytes to develop into lung macrophages and promote lung tissue damage depends upon their phenotypic pattern of differentiation and activation. Whether this phenotypic pattern varies with COPD severity is unknown. Here we characterize the activation and differentiation status of circulating monocytes in patients with moderate vs. severe COPD.MethodsBlood monocytes were isolated from normal non-smokers (14), current smokers (13), patients with moderate (9), and severe COPD (11). These cells were subjected to analysis by flow cytometry to characterize the expression of activation markers, chemoattractant receptors, and surface markers characteristic of either M1- or M2-type macrophages.ResultsPatients with severe COPD had increased numbers of total circulating monocytes and non-classical patrolling monocytes, compared to normal subjects and patients with moderate COPD. In addition, while the percentage of circulating monocytes that expressed an M2-like phenotype was reduced in patients with either moderate or severe disease, the levels of expression of M2 markers on this subpopulation of monocytes in severe COPD was significantly elevated. This was particularly evident for the expression of the chemoattractant receptor CCR5.ConclusionsBlood monocytes in severe COPD patients undergo unexpected pre-differentiation that is largely characteristic of M2-macrophage polarization, leading to the emergence of an unusual M2-like monocyte population with very high levels of CCR5. These results show that circulating monocytes in patients with severe COPD possess a cellular phenotype which may permit greater mobilization to the lung, with a pre-existing bias toward a potentially destructive inflammatory phenotype.

“Hidden” Preoperative Blood Loss With Extracapsular Versus Intracapsular Hip Fractures: What Is the Difference?:

Purpose: Excessive blood loss with hip fracture management has been shown to result in increased rates of complications. Our goal is to compare blood loss and transfusion rates between patients with intracapsular and extracapsular (both intertrochanteric (IT) and subtrochanteric (ST)) hip fractures. Methods: 472 patients were evaluated over a five-year period. Those who presented to the hospital with a proximal femur fracture (femoral neck, IT or ST) were considered for the study. Exclusion criteria included polytrauma, gunshot injuries, periprosthetic fractures, and non-operative management. Primary endpoint was hemoglobin (Hgb) drop from admission to day of surgery (DOS); secondary endpoint was need for pre-op transfusion and discharge location. Results: 304 patients were analyzed who sustained a proximal femur fracture. Median IC Hgb drop was 0.6g/dL; median EC Hgb drop was 1.1g/dL from admission to DOS (p = 0.0272). Rate of pre-operative transfusions was higher in EC (36/194 = 18.6%) than IC fractures (5/105 = 4.5%) (p = 0.0006), and overall transfusion rates remained higher throughout hospital stay (55.7% EC vs. 32.7% IC; p = 0.0001). Breakdown of bleeding rate and tranfusion rates between IT and ST fractures were not significant (p = 0.07; p = 0.4483). Extracapsular hip fractures were more likely to be discharged to a skilled nursing facility (SNF) (84.4% EC vs. 73.8% IC; p = 0.027). Conclusion: Intracapsular hip fractures have significantly less pre-operative blood loss and fewer pre-operative transfusions than their extracapsular counterparts. These findings can be used to establish appropriate pre-operative resuscitative efforts, ensuring that hip fracture protocols account for the increased likelihood of blood loss in extracapsular fractures.