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1.
Blood ; 140(9): 1020-1037, 2022 09 01.
Article in English | MEDLINE | ID: mdl-35737916

ABSTRACT

Acute lung injury, referred to as the acute chest syndrome, is a major cause of morbidity and mortality in patients with sickle cell disease (SCD), which often occurs in the setting of a vaso-occlusive painful crisis. P-selectin antibody therapy reduces hospitalization of patients with SCD by ∼50%, suggesting that an unknown P-selectin-independent mechanism promotes remaining vaso-occlusive events. In patients with SCD, intraerythrocytic polymerization of mutant hemoglobin promotes ischemia-reperfusion injury and hemolysis, which leads to the development of sterile inflammation. Using intravital microscopy in transgenic, humanized mice with SCD and in vitro studies with blood from patients with SCD, we reveal for the first time that the sterile inflammatory milieu in SCD promotes caspase-4/11-dependent activation of neutrophil-gasdermin D (GSDMD), which triggers P-selectin-independent shedding of neutrophil extracellular traps (NETs) in the liver. Remarkably, these NETs travel intravascularly from liver to lung, where they promote neutrophil-platelet aggregation and the development of acute lung injury. This study introduces a novel paradigm that liver-to-lung embolic translocation of NETs promotes pulmonary vascular vaso-occlusion and identifies a new GSDMD-mediated, P-selectin-independent mechanism of lung injury in SCD.


Subject(s)
Acute Lung Injury , Anemia, Sickle Cell , Extracellular Traps , Phosphate-Binding Proteins , Pore Forming Cytotoxic Proteins , Reperfusion Injury , Acute Lung Injury/etiology , Animals , Liver , Lung/blood supply , Mice , Mice, Transgenic , P-Selectin , Phosphate-Binding Proteins/metabolism , Pore Forming Cytotoxic Proteins/metabolism , Reperfusion Injury/complications
2.
Hepatology ; 72(6): 2165-2181, 2020 12.
Article in English | MEDLINE | ID: mdl-32190913

ABSTRACT

BACKGROUND AND AIMS: Hepatic crisis is an emergent complication affecting patients with sickle cell disease (SCD); however, the molecular mechanism of sickle cell hepatobiliary injury remains poorly understood. Using the knock-in humanized mouse model of SCD and SCD patient blood, we sought to mechanistically characterize SCD-associated hepato-pathophysiology applying our recently developed quantitative liver intravital imaging, RNA sequence analysis, and biochemical approaches. APPROACH AND RESULTS: SCD mice manifested sinusoidal ischemia, progressive hepatomegaly, liver injury, hyperbilirubinemia, and increased ductular reaction under basal conditions. Nuclear factor kappa B (NF-κB) activation in the liver of SCD mice inhibited farnesoid X receptor (FXR) signaling and its downstream targets, leading to loss of canalicular bile transport and altered bile acid pool. Intravital imaging revealed impaired bile secretion into the bile canaliculi, which was secondary to loss of canalicular bile transport and bile acid metabolism, leading to intrahepatic bile accumulation in SCD mouse liver. Blocking NF-κB activation rescued FXR signaling and partially ameliorated liver injury and sinusoidal ischemia in SCD mice. CONCLUSIONS: These findings identify that NF-κB/FXR-dependent impaired bile secretion promotes intrahepatic bile accumulation, which contributes to hepatobiliary injury of SCD. Improved understanding of these processes could potentially benefit the development of therapies to treat sickle cell hepatic crisis.


Subject(s)
Anemia, Sickle Cell/complications , Bile/metabolism , Cholestasis/etiology , Hepatic Insufficiency/etiology , Liver/pathology , Adolescent , Adult , Anemia, Sickle Cell/blood , Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/genetics , Animals , Bile Ducts, Intrahepatic/diagnostic imaging , Bile Ducts, Intrahepatic/pathology , Cholestasis/pathology , Cholestasis/prevention & control , Disease Models, Animal , Female , Gene Knock-In Techniques , Hemoglobin, Sickle/genetics , Hepatic Insufficiency/pathology , Hepatic Insufficiency/prevention & control , Humans , Intravital Microscopy , Liver/diagnostic imaging , Male , Mice , Middle Aged , NF-kappa B/antagonists & inhibitors , NF-kappa B/drug effects , NF-kappa B/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Signal Transduction/drug effects , Young Adult
3.
Am J Respir Crit Care Med ; 201(1): 33-46, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31498653

ABSTRACT

Rationale: Intraerythrocytic polymerization of Hb S promotes hemolysis and vasoocclusive events in the microvasculature of patients with sickle cell disease (SCD). Although platelet-neutrophil aggregate-dependent vasoocclusion is known to occur in the lung and contribute to acute chest syndrome, the etiological mechanisms that trigger acute chest syndrome are largely unknown.Objectives: To identify the innate immune mechanism that promotes platelet-neutrophil aggregate-dependent lung vasoocclusion and injury in SCD.Methods:In vivo imaging of the lung in transgenic humanized SCD mice and in vitro imaging of SCD patient blood flowing through a microfluidic system was performed. SCD mice were systemically challenged with nanogram quantities of LPS to trigger lung vasoocclusion.Measurements and Main Results: Platelet-inflammasome activation led to generation of IL-1ß and caspase-1-carrying platelet extracellular vesicles (EVs) that bind to neutrophils and promote platelet-neutrophil aggregation in lung arterioles of SCD mice in vivo and SCD human blood in microfluidics in vitro. The inflammasome activation, platelet EV generation, and platelet-neutrophil aggregation were enhanced by the presence of LPS at a nanogram dose in SCD but not control human blood. Inhibition of the inflammasome effector caspase-1 or IL-1ß pathway attenuated platelet EV generation, prevented platelet-neutrophil aggregation, and restored microvascular blood flow in lung arterioles of SCD mice in vivo and SCD human blood in microfluidics in vitro.Conclusions: These results are the first to identify that platelet-inflammasome-dependent shedding of IL-1ß and caspase-1-carrying platelet EVs promote lung vasoocclusion in SCD. The current findings also highlight the therapeutic potential of targeting the platelet-inflammasome-dependent innate immune pathway to prevent acute chest syndrome.


Subject(s)
Anemia, Sickle Cell/complications , Anemia, Sickle Cell/immunology , Extracellular Vesicles/immunology , Inflammasomes/immunology , Lung Injury/etiology , Lung Injury/physiopathology , Platelet Aggregation/immunology , Acute Chest Syndrome/etiology , Acute Chest Syndrome/physiopathology , Anemia, Sickle Cell/physiopathology , Animals , Humans , Mice , Mice, Transgenic , Models, Animal , Neutrophils/immunology
4.
Pediatr Blood Cancer ; 65(8): e27081, 2018 08.
Article in English | MEDLINE | ID: mdl-29693797

ABSTRACT

BACKGROUND: Adherence to illness self-management among youth with sickle cell disease (SCD) positively impacts health outcomes and decreases overall healthcare costs. Despite this, children with SCD face several barriers to adherence, with adherence rates that remain moderate to low. The current feasibility study examined the Intensive Training Program (ITP), a mobile health (mHealth) intervention for youth with SCD designed to promote disease knowledge, adherence, and patient-provider communication. PROCEDURE: Youth with SCD prescribed hydroxyurea between ages 7-18 completed baseline disease knowledge and psychosocial assessments and then were provided with the ITP app. Youth participated in the 90-day ITP, during which they completed three education modules, tracked adherence through daily self-recorded videos on the app, and received video messages from providers. Participants completed poststudy knowledge, psychosocial, and feasibility questionnaires. Medication possession ratio (MPR) was obtained via pharmacy-refill rates. RESULTS: Thirty-two youths (mean age = 13.0 years) participated, with an average adherence tracking rate of 0.6 (standard deviation = 0.34). All participants demonstrated increased MPR (0.57-0.74, P < 0.001, d = 0.75) and disease knowledge (59.6-88.6%, P < 0.001). There was variable engagement in the ITP; completers demonstrated significantly better SCD-related functioning (P < 0.05), higher parent-reported treatment functioning (P < 0.05), and lower pain impact than noncompleters of the ITP (P < 0.05). CONCLUSIONS: Results support the ITP can feasibly be implemented to promote adherence among youth with SCD. All participants demonstrated increased adherence and disease knowledge. However, there was variable engagement and only intervention completers showed improvements in psychosocial outcomes. Further research is needed to evaluate long-term outcomes and ways to promote engagement in mHealth interventions among the youth.


Subject(s)
Anemia, Sickle Cell , Health Knowledge, Attitudes, Practice , Patient Education as Topic/methods , Quality of Life , Self-Management/methods , Telemedicine/methods , Adolescent , Child , Feasibility Studies , Female , Humans , Male , Mobile Applications , Patient Compliance
5.
J Med Internet Res ; 20(8): e10056, 2018 08 03.
Article in English | MEDLINE | ID: mdl-30076127

ABSTRACT

BACKGROUND: Pain is the most common physical symptom requiring medical care, yet the current methods for assessing pain are sorely inadequate. Pain assessment tools can be either too simplistic or take too long to complete to be useful for point-of-care diagnosis and treatment. OBJECTIVE: The aim was to develop and test Painimation, a novel tool that uses graphic visualizations and animations instead of words or numeric scales to assess pain quality, intensity, and course. This study examines the utility of abstract animations as a measure of pain. METHODS: Painimation was evaluated in a chronic pain medicine clinic. Eligible patients were receiving treatment for pain and reported pain more days than not for at least 3 months. Using a tablet computer, participating patients completed the Painimation instrument, the McGill Pain Questionnaire (MPQ), and the PainDETECT questionnaire for neuropathic symptoms. RESULTS: Participants (N=170) completed Painimation and indicated it was useful for describing their pain (mean 4.1, SE 0.1 out of 5 on a usefulness scale), and 130 of 162 participants (80.2%) agreed or strongly agreed that they would use Painimation to communicate with their providers. Animations selected corresponded with pain adjectives endorsed on the MPQ. Further, selection of the electrifying animation was associated with self-reported neuropathic pain (r=.16, P=.03), similar to the association between neuropathic pain and PainDETECT (r=.17, P=.03). Painimation was associated with PainDETECT (r=.35, P<.001). CONCLUSIONS: Using animations may be a faster and more patient-centered method for assessing pain and is not limited by age, literacy level, or language; however, more data are needed to assess the validity of this approach. To establish the validity of using abstract animations ("painimations") for communicating and assessing pain, apps and other digital tools using painimations will need to be tested longitudinally across a larger pain population and also within specific, more homogenous pain conditions.


Subject(s)
Medical Informatics/methods , Pain Measurement/methods , Pain/diagnosis , Communication , Cross-Sectional Studies , Feasibility Studies , Female , Humans , Male , Middle Aged , Pain/pathology , Surveys and Questionnaires
6.
J Pediatr Nurs ; 42: 86-91, 2018.
Article in English | MEDLINE | ID: mdl-30219304

ABSTRACT

PURPOSE: Our investigative team is integrating mobile health technologies into pediatric blood and marrow transplant (PBMT) care. We aim to evaluate whether patient-generated health data can be used to monitor health status and enhance symptom management. While there are numerous health-related apps, none address the symptoms or care needs specific to PBMT patients. This article describes development of the Technology Recording to better Understand Pediatric Blood and Marrow Transplant (TRU-PBMT) mobile application. DESIGN AND METHODS: A one-time survey was distributed to PBMT clinicians, caregivers, and outpatients to elicit feedback and suggestions for the app's design. RESULTS: Feedback from clinicians (n = 23), caregivers (n = 5), and PBMT outpatients (n = 4) indicated the app would be acceptable and useable with this group of patients between eight and eighteen years of age. Suggestions from respondents included: making the app language and graphics more child-friendly; adding symptoms such as fatigue, mucositis, bleeding; and a visual stool chart. CONCLUSION: Patient, caregiver, and clinician feedback was valuable in creation of the TRU-PBMT app. We designed a pediatric friendly, PBMT-symptom-specific app, which we will test in future studies. IMPLICATIONS FOR PRACTICE: This app facilitates patient-generated health data collection and informs health care plans.


Subject(s)
Bone Marrow Transplantation , Patient Portals/standards , Patient Reported Outcome Measures , Telemedicine/standards , Bone Marrow , Child , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Patient Portals/statistics & numerical data
7.
J Pediatr Hematol Oncol ; 39(3): 223-229, 2017 04.
Article in English | MEDLINE | ID: mdl-28099398

ABSTRACT

Iron chelation therapy can prevent iron overload for pediatric patients with sickle cell disease and ß-thalassemia major; however, adherence is suboptimal. Therefore, we developed an intensive training program (ITP), to improve medication management and disease knowledge. The objectives were to determine feasibility of the ITP and its preliminary impact on adherence, disease knowledge, and health outcomes. Pediatric patients were recruited to participate in the ITP over a 90-day period and were followed for 6 months. The ITP consisted of 3 components: (1) provider-led education modules; (2) patient recording daily videos of at-home medication administration; and (3) provider feedback through video messages through the ITP app. Eleven patients participated (mean=12.4 y). Initially, patients endorsed high satisfaction and ease of use and tracked their medication usage 81% (24 out of 30) of days. At 90 days, adherence rates remained consistent (80%) and disease knowledge retention was high (96%). At 6 months, participants exhibited a clinically relevant decrease in serum ferritin, which trended toward statistical significance (P=0.068). Medication possession ratio did not significantly increase (0.65 to 0.72; not significant). The mobile ITP was feasibly implemented in a clinical setting; in addition, high levels of compliance, disease knowledge retention, and acceptance encourage larger studies evaluating mobile health technology to improve child health parameters.


Subject(s)
Blood Transfusion , Chelation Therapy/methods , Patient Compliance , Patient Medication Knowledge , Adolescent , Child , Education , Female , Humans , Iron Chelating Agents , Male , Patient Education as Topic , Pilot Projects , Video Recording , Young Adult
8.
Hemoglobin ; 39(3): 162-8, 2015.
Article in English | MEDLINE | ID: mdl-25831427

ABSTRACT

Patients with sickle cell disease frequently experience severe pain events that lead to unplanned healthcare utilization. Mobile health tools (mHealth) may help prevent these events by providing remote monitoring and self-management support. This article describes the feasibility of the Sickle cell disease Mobile Application to Record symptoms via Technology (SMART), an mHealth app developed to help sickle cell disease patients monitor and manage their day-to-day symptoms. Fifteen patients recorded their pain intensity using a paper visual analog scale (VAS) and then repeated this measurement using an electronic VAS pain measure on SMART. Patients continued using SMART to record clinical symptoms, pain intensity, location and perceived severity, and treatment strategies for at least 28 days. Patient median age was 29 years (range 16-54); 60.0% were male. There was a high intraclass correlation between pain measurements entered on the paper VAS and SMART on the iPhone and the iPad We found a strong association between patient perceived pain severity and pain intensity entries using SMART (b = 1.71; p < 0.01). Daily compliance with SMART entries was a mean 75.0%, with a high of 85.7% in week 1 and low of 57.9% in week 4; however, one-third (n = 5) of the patients were 100.0% compliant even in week 4. Patients who were over age 35 or used an iPad for the study had the highest compliance rates. This study showed that SMART is a useable and feasible method for monitoring daily pain symptoms among adolescents and adults with sickle cell disease-related pain.


Subject(s)
Anemia, Sickle Cell/complications , Pain Management , Pain Measurement , Pain/etiology , Telemedicine , Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Mobile Applications , Pain Management/methods , Pain Measurement/methods , Patient Acceptance of Health Care , Patient Satisfaction , Self Report , Telemedicine/methods , Young Adult
9.
Am J Hematol ; 89(5): 530-5, 2014 May.
Article in English | MEDLINE | ID: mdl-24478166

ABSTRACT

In this study, the relationship of clinical differences among patients with sickle cell disease (SCD) was examined to understand the major contributors to early mortality in a contemporary cohort. Survival data were obtained for 542 adult subjects who were enrolled since 2002 at three university hospitals in the southeast United States. Subjects were followed up for a median of 9.3 years. At enrollment, clinical parameters were collected, including hemoglobin (Hb) genotype, baseline laboratory values, comorbidities, and medication usage. Levels of soluble adhesion molecules were measured for a subset of 87 subjects. The relationship of clinical characteristics to survival was determined using regression analysis. Median age at enrollment was 32 years. Median survival was 61 years for all subjects. Median survival for Hb SS and Sß(0) was 58 years and for Hb SC and Sß(+) was 66 years. Elevated white blood count, lower estimated glomerular filtration rate, proteinuria, frequency of pain crises, pulmonary hypertension, cerebrovascular events, seizures, stroke, sVCAM-1, and short-acting narcotics use were significantly associated with decreased survival. Forty-two percent of subjects were on hydroxyurea therapy, which was not associated with survival. SCD continues to reduce life expectancy for affected individuals, particularly those with Hb Sß(0) and SS. Not only were comorbidities individually associated with decreased survival but also an additive effect was observed, thus, those with a greater number of negative endpoints had worse survival (P < 0.0001). The association of higher sVCAM-1 levels with decreased survival suggests that targeted therapies to reduce endothelial damage and inflammation may also be beneficial.


Subject(s)
Anemia, Sickle Cell/mortality , Adolescent , Adult , Aged , Aged, 80 and over , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/pathology , Cohort Studies , Comorbidity , Female , Genotype , Humans , Male , Middle Aged , Southeastern United States/epidemiology , Survival Analysis , Young Adult
10.
Hemoglobin ; 38(2): 99-103, 2014.
Article in English | MEDLINE | ID: mdl-24512633

ABSTRACT

The widespread use of mobile phones among patients provides a unique opportunity for the development of mobile health intervention designed specifically for sickle cell disease, which will improve self-management as well as health care delivery. Our objective was to determine the receptiveness of patients with sickle cell disease to technology and a mobile application (app) designed for sickle cell disease. Phase I included 100 patients who completed a survey inquiring about receptiveness to technology and use of mobile devices to self-manage and communicate with providers. Phase II surveyed 17 additional patients who tested a newly developed sickle cell disease app, to report its usability and utility. In Phase I, on a 0-10 Likert scale where 0 is not comfortable, and 10 is extremely comfortable, 87.0% of participants reported >5 comfort level using a mobile device for health care management. Participants were comfortable with texting (81.0%) and emailing (77.0%) but not with social media (40.0%). Most participants (84.0%) owned computer devices (desktops, laptops, tablets, or iPads), and 92.0% owned mobile devices. In Phase II, participants reported that the app tested was useful to track pain (88.0%), and 94.0% reported that it was easy to use, practical, and useful for health self-management. All reported that the app was useful to help one communicate with providers. Following the use of our app, patients found it an extremely valuable tool for tracking pain, health management, and communicating with providers. We conclude that mobile technology might provide an appropriate venue for sickle cell disease healthcare management.


Subject(s)
Anemia, Sickle Cell/therapy , Mobile Applications/statistics & numerical data , Patient Acceptance of Health Care/statistics & numerical data , Self Care/methods , Cell Phone/statistics & numerical data , Humans , Surveys and Questionnaires , Text Messaging/statistics & numerical data
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