Publications by authors named "Marcus A Carden"

People living with sickle cell disease (SCD) experience complications indicative of an accelerated aging phenotype typified by early decline in physical function and increased risk for age-related conditions. Cellular senescence, measured by expression of p16 in peripheral T-lymphocytes, is recognized as one of the underlying contributors to organismal aging. To examine if cellular senescence is increased in SCD patients, we cross-sectionally measured and compared expression of p16 mRNA in peripheral blood T lymphocytes in 18 adolescents and young adults with SCD to 27 similarly aged individuals without SCD.

View Article and Find Full Text PDF

While microscopy-based cellular assays, including microfluidics, have significantly advanced over the last several decades, there has not been concurrent development of widely-accessible techniques to analyze time-dependent microscopy data incorporating phenomena such as fluid flow and dynamic cell adhesion. As such, experimentalists typically rely on error-prone and time-consuming manual analysis, resulting in lost resolution and missed opportunities for innovative metrics. We present a user-adaptable toolkit packaged into the open-source, standalone Interactive Cellular assay Labeled Observation and Tracking Software (iCLOTS).

View Article and Find Full Text PDF

Health education for children with chronic illnesses (i.e., sickle cell disease [SCD]) has focused on educating adult caregivers with minimal consideration to educating the pediatric patients.

View Article and Find Full Text PDF

In patients with sickle cell disease (SCD) and diabetes mellitus (DM), hemoglobin A (HbA ) is unreliable and the American Diabetes Association recommends monitoring long-term glycemia by measuring serum glucose, but use of serum fructosamine (SF), a measurement independent of red cell lifespan, has been reported. SF as a screen for DM in SCD, however, is not standardized and its relationship to serum glucose has not been validated. Further, screening for DM was not adequately addressed in the 2014 National Heart, Lung, and Blood Institute (NHLBI) guidelines for SCD management.

View Article and Find Full Text PDF

How TPEx impacts rituximab effectiveness in iTTP patients is not fully understood. In iTTP patients on therapeutic plasma exchange, rituximab eliminates circulating CD20 B and T cells in 24 hours for at least 1 week.

View Article and Find Full Text PDF

Sickle cell anemia (SCA) is associated with morbidity and early death. While the switch from fetal to sickle hemoglobin during the first months of life results in hemolytic anemia with reticulocytosis, the role of the reticulocyte in the pathophysiology and prognosis of SCA is not well-defined. Reticulocytes have unique cytoskeletal and membrane components that allow them to be distinguished from mature sickle erythrocytes in the circulation.

View Article and Find Full Text PDF

Sickle cell disease afflicts millions of people worldwide and approximately 100,000 Americans. Complications are myriad and arise as a result of complex pathological pathways 'downstream' to a point mutation in DNA, and include red blood cell membrane damage, inflammation, chronic hemolytic anemia with episodic vaso-occlusion, ischemia and pain, and ultimately risk of cumulative organ damage with reduced lifespan of affected individuals. The National Heart, Lung, and Blood Institute's 2014 evidence-based guideline for sickle cell disease management states that additional research is needed before investigational curative therapies will be widely available to most patients with sickle cell disease.

View Article and Find Full Text PDF

Vaso-occlusive pain events (VOE) are the leading cause of emergency department (ED) visits in sickle cell anemia (SCA). This study assessed the variability in use of intravenous fluids (IVFs), and the association of normal saline bolus (NSB), on pain and other clinical outcomes in children with SCA, presenting to pediatric emergency departments (PED) with VOE. Four-hundred charts of children age 3-21 years with SCA/VOE receiving parenteral opioids at 20 high-volume PEDs were evaluated in a retrospective study.

View Article and Find Full Text PDF

Background: Delayed hemolytic transfusion reactions (DHTRs) are serious complications of RBC transfusion that can occur in previously alloimmunized patients. Patients who require episodic transfusions during heightened inflammatory states, such as patients with sickle cell disease (SCD), are particularly prone to alloimmunization and developing DHTRs with hyperhemolysis. While efforts to mitigate these hemolytic episodes via immunosuppressive drugs can be employed, the relative efficacy of various treatment options remains incompletely understood.

View Article and Find Full Text PDF

Renal medullary carcinoma (RMC) is one of the most aggressive renal cell carcinomas. It predominantly afflicts young adults and adolescents with sickle cell trait and other sickle hemoglobinopathies, and is refractory to targeted and antiangiogenic therapies used in patients with clear-cell renal cell carcinoma. Platinum-based cytotoxic chemotherapy is the mainstay for RMC treatment.

View Article and Find Full Text PDF

Hemostasis encompasses an ensemble of interactions among platelets, coagulation factors, blood cells, endothelium, and hemodynamic forces, but current assays assess only isolated aspects of this complex process. Accordingly, here we develop a comprehensive in vitro mechanical injury bleeding model comprising an "endothelialized" microfluidic system coupled with a microengineered pneumatic valve that induces a vascular "injury". With perfusion of whole blood, hemostatic plug formation is visualized and "in vitro bleeding time" is measured.

View Article and Find Full Text PDF

Abnormal sickle red blood cell (sRBC) biomechanics, including pathological deformability and adhesion, correlate with clinical severity in sickle cell disease (SCD). Clinical intravenous fluids (IVFs) of various tonicities are often used during treatment of vaso-occlusive pain episodes (VOE), the major cause of morbidity in SCD. However, evidence-based guidelines are lacking, and there is no consensus regarding which IVFs to use during VOE.

View Article and Find Full Text PDF

Objective: Vaso-occlusive crisis (VOC) is a complex process that occurs in patients with sickle cell disease (SCD) and is often associated with pain and urgent hospitalization. A major instigator of VOC is microvascular obstruction by pathologically stiffened sickle red blood cells (RBCs), and thus, therapy relies heavily on optimizing intravenous fluid (IVF) hydration to increase RBC deformability. However, no evidence-based guidelines regarding the choice of IVF currently exist.

View Article and Find Full Text PDF

Renal medullary carcinoma (RMC) was first described over two decades ago as the seventh sickle nephropathy. Survival after diagnosis with metastatic disease still rarely extends beyond 1 year, with recent reports of median overall survival in patients treated with platinum therapy being just 10 months. We describe our experience using platinum-based chemotherapy plus the proteasome inhibitor bortezomib to treat metastatic RMC in two pediatric patients who had complete responses.

View Article and Find Full Text PDF

Monomorphic plasmacytoma-type posttransplant lymphoproliferative disorder (PTLD) has not been reported after pediatric hematopoietic stem cell transplantation. We present a child with hepatitis-associated severe aplastic anemia who underwent an unrelated allogeneic hematopoietic stem cell transplantation and subsequently developed graft failure and an Epstein-Barr virus-positive monomorphic plasmacytoma-type PTLD of recipient origin. Despite broad-spectrum antimicrobials, weaning immunosuppression, rituximab administration, and a stem cell boost she died from complications of PTLD and a fungal pulmonary infection on day +78.

View Article and Find Full Text PDF

This study was conducted to measure the health literacy (HL) and disease-specific knowledge (DSK) of caregivers for children with sickle cell disease (SCD) and relate them to their child's health care utilization. The authors conducted a cross-sectional study of caregiver-child dyads attending an urban pediatric sickle cell clinic. Caregivers were administered the Shortened Test of Functional Health Literacy (S-TOFHLA) and a locally developed DSK questionnaire.

View Article and Find Full Text PDF

A two-year-old girl with congenital dyserythropoietic anemia (CDA) acutely developed fever, tachypnea, and increased oxygen requirement. Chest X-ray revealed bilateral interstitial infiltrates and mild cardiomegaly. Blood cultures grew no infectious agents, while pulmonary specimens grew cytomegalovirus (CMV).

View Article and Find Full Text PDF