Identifying pediatric heart murmurs and distinguishing innocent from pathologic using deep learning.

OBJECTIVE: To develop a deep learning algorithm to perform multi-class classification of normal pediatric heart sounds, innocent murmurs, and pathologic murmurs. METHODS: We prospectively enrolled children under age 18 being evaluated by the Division of Pediatric Cardiology. Parents provided consent for a deidentified recording of their child's heart sounds with a digital stethoscope. Innocent murmurs were validated by a pediatric cardiologist and pathologic murmurs were validated by echocardiogram. To augment our collection of normal heart sounds, we utilized a public database of pediatric heart sound recordings (Oliveira, 2022). We propose two novel approaches for this audio classification task. We train a vision transformer on either Markov transition field or Gramian angular field image representations of the frequency spectrum. We benchmark our results against a ResNet-50 CNN trained on spectrogram images. RESULTS: Our final dataset consisted of 366 normal heart sounds, 175 innocent murmurs, and 216 pathologic murmurs. Innocent murmurs collected include Still's murmur, venous hum, and flow murmurs. Pathologic murmurs included ventricular septal defect, tetralogy of Fallot, aortic regurgitation, aortic stenosis, pulmonary stenosis, mitral regurgitation and stenosis, and tricuspid regurgitation. We find that the Vision Transformer consistently outperforms the ResNet-50 on all three image representations, and that the Gramian angular field is the superior image representation for pediatric heart sounds. We calculated a one-vs-rest multi-class ROC curve for each of the three classes. Our best model achieves an area under the curve (AUC) value of 0.92 ± 0.05, 0.83 ± 0.04, and 0.88 ± 0.04 for identifying normal heart sounds, innocent murmurs, and pathologic murmurs, respectively. CONCLUSION: We present two novel methods for pediatric heart sound classification, which outperforms the current standard of using a convolutional neural network trained on spectrogram images. To our knowledge, we are the first to demonstrate multi-class classification of pediatric murmurs. Multiclass output affords a more explainable and interpretable model, which can facilitate further model improvement in the downstream model development cycle and enhance clinician trust and therefore adoption.

The use of once-daily LCP-Tacrolimus with adolescent and young adult solid organ transplant recipients.

BACKGROUND: Adolescent and young adult (AYA) solid organ transplant (SOT) recipients experience increased rates of rejection and graft loss surrounding the time of health care transition, in part due to poor medication adherence. This study aims to examine the impact of a once-daily formulation of tacrolimus, LCP-tacrolimus (LCPT), on medication adherence for AYA SOT patients. METHODS: A retrospective descriptive analysis was performed for all patients who underwent SOT and were prescribed LCPT after the age of 12 at our single-center pediatric hospital. Medication adherence was assessed via provider documentation and the medication level variability index (MLVI). RESULTS: Twenty-nine patients were prescribed LCPT as part of their immunosuppression regimen. Twenty patients were converted to LCPT from immediate-acting (IR) tacrolimus; six patients were initiated immediately following transplant, and three patients were unable to receive LCPT due to insurance denial. There was a numeric improvement in medication adherence for converted patients when measured by provider assessment (45.0% vs. 68.4%, p = .140) and MLVI (40.0% vs. 71.4%, p = .276), though these did not reach statistical significance. There were no differences in episodes of rejection or adverse effects. LCPT prescription was not associated with decreased medication burden, and two patients transitioned back to IR tacrolimus due to increased cost. CONCLUSIONS: LCPT use did not significantly improve patient adherence; however, it resulted in numerically higher perceived and measured adherence rates. LCPT appears to be safe and effective in the management of SOT recipients; however, it may not affect pill burden and may result in a higher financial burden. Use may be considered for a select group of AYA SOT recipients.

Landscape of cancer clinical trials in India - a comprehensive analysis of the Clinical Trial Registry-India.

Background: Cancer is one of the leading causes of morbidity and mortality in India. Clinical trials are critical for driving innovation in cancer therapy, diagnosis, and prevention. This study aims to depict the evolving landscape of cancer clinical trials in India by analysing the clinical trials registered in Clinical Trial Registry-India (CTRI). Methods: We identified cancer trials registered in CTRI (between 2007 and 2021) using search terms adapted from the cancer types defined by the National Cancer Institute (USA). We then collated and analysed the publicly available information from CTRI (cancer subtypes, type of trial, treatment intent, type of intervention, sponsor type, recruitment countries) and used descriptive statistics to illustrate the overall as well as year-to-year trend. Findings: In total, we identified 1988 cancer trials, the majority of which focused on treating cancer (63%) and rest of the trials aimed at optimising the operational aspects of surgery (19%), mitigating treatment-related toxicity (10.6%), or treating cancer-related symptoms (7.8%). Focusing on trials with the intent of treating cancer, we found that most were investigating solid tumours as opposed to haematological malignancies with the most prominent cancer subtypes being breast cancer (17%), head and neck cancer (9.8%), lung cancer (9.6%), and cervical cancer (6.6%). The number of trials conducted in a given cancer subtype from our analysis overall correlated to the incidence, mortality, and 5-year prevalence of the respective cancer subtype in India; however, head and neck cancer and cervical cancer were underrepresented in trials as compared with the disease burden. The most common type of intervention was investigational drugs. The most common sponsor types were global pharmaceutical industry (26%) and research institution and hospital (26%). Despite a relatively high cancer burden, the availability of cancer trials in the Northeastern states of India was limited. Interpretation: There is a pressing need for clinical cancer research in India to be better aligned with the nation's healthcare needs and disease burden, focusing on prevalent and deadly cancers while ensuring the availability of clinical trials across geographic regions and underserved populations. Funding: Pi Health USA, a fully owned subsidiary of BeiGene Ltd.

Association of JAK2V617F allele burden and clinical correlates in polycythemia vera: a systematic review and meta-analysis.

Janus kinase 2 (JAK2) V617F mutation is present in most patients with polycythemia vera (PV). One persistently puzzling aspect unresolved is the association between JAK2V617F allele burden (also known as variant allele frequency) and the relevant clinical characteristics. Numerous studies have reported associations between allele burden and both hematologic and clinical features. While there are strong indications linking high allele burden in PV patients with symptoms and clinical characteristics, not all associations are definitive, and disparate and contradictory findings have been reported. Hence, this study aimed to synthesize existing data from the literature to better understand the association between JAK2V617F allele burden and relevant clinical correlates. Out of the 1,851 studies identified, 39 studies provided evidence related to the association between JAK2V617F allele burden and clinical correlates, and 21 studies were included in meta-analyses. Meta-analyses of correlation demonstrated that leucocyte and erythrocyte counts were significantly and positively correlated with JAK2V617F allele burden, whereas platelet count was not. Meta-analyses of standardized mean difference demonstrated that leucocyte and hematocrit were significantly higher in patients with higher JAK2V617F allele burden, whereas platelet count was significantly lower. Meta-analyses of odds ratio demonstrated that patients who had higher JAK2V617F allele burden had a significantly greater odds ratio for developing pruritus, splenomegaly, thrombosis, myelofibrosis, and acute myeloid leukemia. Our study integrates data from approximately 5,462 patients, contributing insights into the association between JAK2V617F allele burden and various hematological parameters, symptomatic manifestations, and complications. However, varied methods of data presentation and statistical analyses prevented the execution of high-quality meta-analyses.

Glycemic Control and Obesity Among People With Type 2 Diabetes in Europe and Australia: A Retrospective Cohort Analysis.

INTRODUCTION: In people with type 2 diabetes (PwT2D) who also have obesity, efforts targeting weight loss, including lifestyle, medication and surgical interventions, are recommended. The objective of this study was to explore the relationship between glycemic control and obesity among PwT2D in Europe and Australia using recent real-world data and applying consistent methodology across countries. METHODS: Retrospective study utilizing IQVIA electronic medical records (EMR) databases grouped into panels based on specialty of contributing physicians. General practitioner (GP) and endocrinologist/diabetologist (E/D) panels were used in Germany and France, while GP panels were used in Italy, UK and Australia. The Spanish database included all physician specialties. The sample included PwT2D with glycated hemoglobin A1c (HbA1c) and body mass index (BMI) values measured within 90 days of each other between January 2015 and December 2018 (second record termed the 'index date'). PwT2D had a 1-year baseline period and a recorded HbA1c at the end of the 1-year post-index period. RESULTS: The final sample comprised 194,729 PwT2D. At baseline, across countries/panels, 36.8-58.0% were above HbA1c target (HbA1c ≥ 7%) and 39.4-56.7% had obesity (BMI ≥ 30.0 kg/m2). Mean HbA1c ranged from 6.9 to 7.6% and mean BMI ranged from 29.3-31.6 kg/m2. At baseline, a higher proportion of PwT2D with obesity (40.8-64.2%) were above HbA1c target compared to their counterparts without obesity (32.2-52.4%). A higher proportion of patients with obesity at baseline (38.1-60.6%) had post-index HbA1c above target compared to their counterparts without obesity (30.9-56.0%). In logistic regression, patients with obesity had substantially lower odds of post-index HbA1c below target compared to those without obesity in all countries/panels except for France (E/D), Spain and Australia. CONCLUSIONS: This study presents data on HbA1c and BMI among type 2 diabetes (T2D) populations in Europe and Australia. A notable proportion of PwT2D had obesity and were above HBA1c target. Higher BMI was associated with poorer glycemic control.

Suicidality associated with decreased help-seeking attitudes in college students: Implications for identifying and treating at-risk students.

Suicide is a leading cause of death in college-aged youth, yet only half of all college students report engaging in professional mental health help-seeking. We examined how the various aspects of young adults' suicidality were associated with their openness to pursue professional mental health care in the future (i.e., "future help-seeking intentions"). Multilevel binary logistic regressions were tested in a sample of 24,446 U.S. college undergraduates with suicidality. The moderating effect of past service utilization on future help-seeking intentions was also tested. Strikingly, young people reporting past-year suicidal ideation, past-year suicidal attempts, and self-reported likelihood of a future suicide attempt demonstrated decreased likelihood of future help-seeking intentions, while those reporting prior diagnosis of a mental health condition and/or past service utilization demonstrated an increased likelihood. Past service utilization also significantly moderated the effect of suicide disclosure, such that youth reporting prior disclosure and prior professional treatment-seeking demonstrated greater odds of future help-seeking intentions relative to those who had disclosed suicidality but never utilized professional services. In order to mitigate the mental health crisis facing youth, further exploration is necessary to understand why students with suicidality do not report openness to seek help. It is also imperative to develop and implement novel strategies to identify at-risk students, understand and alleviate relevant barriers to treatment, and promote positive help-seeking attitudes and behaviors.

The first clinical validation of whole-genome screening on standard trophectoderm biopsies of preimplantation embryos.

Objective: To validate the performance of our laboratory-developed whole-genome screening assay within clinical preimplantation genetic testing environments. Design: Perform a laboratory-developed whole-genome assay on both cell lines and trophectoderm biopsies, subsequently employing the next-generation sequencing procedure to reach a sequencing depth of 30X. Adhere to the Genome Analysis Toolkit best practices for accuracy, sensitivity, specificity, and precision calculations by comparing samples with references. Our assay was then applied to cell lines and biopsies harboring known pathogenic variants, aiming to ascertain these changes solely from the next-generation sequencing data, independent of parental genome information. Settings: Clinical laboratory. Patients: Coriell cell lines and research embryos with known chromosomal or genetic variants. Research trophectoderm biopsies from a couple that are heterozygous carriers for distinct variants in the same autosomal recessive gene (HOGA1). Intervention: Not applicable. Main Outcome Measures: Accuracy, sensitivity, specificity, and precision were assessed by comparing the samples to their references. For samples with known variants, we calculated our sensitivity to detecting established variants. For the research embryos, noncarrier, carrier, and compound heterozygous states of inherited HOGA1 variants were distinguished independently of parental samples. Results: Amplification of DNA from cell lines and embryos yielded success rates exceeding 99.9% and 98.2%, respectively, although maintaining an accuracy of >99.9% for aneuploidy assessment. The accuracy (99.99%), specificity (99.99%), sensitivity (98.0%), and precision (98.1%) of amplified genome in the bottle (reference NA12878) and embryo biopsies were comparable to results on genomic DNA, including mitochondrial heteroplasmy. Using our assay, we achieved >99.99% sensitivity when examining samples with known chromosomal and genetic variants. This encompassed pathogenic CFTR, BRCA1, and other variants, along with uniparental isodisomies and microdeletions such as DiGeorge syndrome. Our research study identified noncarrier, carrier, and compound heterozygous states within trophectoderm biopsies while simultaneously screening for 1,300 other severe monogenic diseases. Conclusion: To our knowledge, this is the first clinical validation of whole-genome embryo screening. In this study, we demonstrated high accuracy for aneuploidy calls (>99.9%) and genetic variants (99.99%), even in the absence of parental genomes. This assay demonstrates advancements in genomic screening and an extended scope for testing capabilities in the realm of preimplantation genetic testing.

Primary auditory cortex is necessary for the acquisition and expression of categorical behavior.

The primary auditory cortex (ACtx) is critically involved in the association of sensory information with specific behavioral outcomes. Such sensory-guided behaviors are necessarily brain-wide endeavors, requiring a plethora of distinct brain areas, including those that are involved in aspects of decision making, motor planning, motor initiation, and reward prediction. ACtx comprises a number of distinct excitatory cell-types that allow for the brain-wide propagation of behaviorally-relevant sensory information. Exactly how ACtx involvement changes as a function of learning, as well as the functional role of distinct excitatory cell-types is unclear. Here, we addressed these questions by designing a two-choice auditory task in which water-restricted, head-fixed mice were trained to categorize the temporal rate of a sinusoidal amplitude modulated (sAM) noise burst and used transient cell-type specific optogenetics to probe ACtx necessity across the duration of learning. Our data demonstrate that ACtx is necessary for the ability to categorize the rate of sAM noise, and this necessity grows across learning. ACtx silencing substantially altered the behavioral strategies used to solve the task by introducing a fluctuating choice bias and increasing dependence on prior decisions. Furthermore, ACtx silencing did not impact the animal's motor report, suggesting that ACtx is necessary for the conversion of sensation to action. Targeted inhibition of extratelencephalic projections on just 20% of trials had a minimal effect on task performance, but significantly degraded learning. Taken together, our data suggest that distinct cortical cell-types synergistically control auditory-guided behavior and that extratelencephalic neurons play a critical role in learning and plasticity.

Real world treatment patterns, healthcare resource use and costs in patients with advanced or metastatic non-small cell lung cancer by EGFR mutation type.

AIMS: This study described treatment patterns, healthcare resource utilization (HRU) and costs among advanced or metastatic non-small cell lung cancer (a/mNSCLC) patients with different epidermal growth factor receptor (EGFR) mutation types. MATERIALS AND METHODS: This retrospective study leveraged NeoGenomics NeoNucleus linked with IQVIA PharMetrics Plus between 01 January 2016 to 30 April 2021 (study period). Patients with evidence of a/mNSCLC between 01 July 2016 to 31 March 2021 (selection window) with EGFR test results indicating exon 19 deletion (exon19del), exon 21 L858R (L858R), or exon 20 insertion (exon20i) mutations were included; date of first observed evidence of a/mNSCLC was the index date. Treatment patterns, all-cause HRU and costs during ≥1 month follow-up were reported for each cohort (exon19del, L858R, and exon20i). RESULTS: A total of 106 exon19del, 75 L858R, and 13 exon20i patients met the study criteria. The prevalence of hospitalization was highest in the exon20i cohort (76.9%), followed by L858R (62.7%) and exon19del (55.7%) cohorts. A higher proportion of patients had evidence of hospice/end-of-life care in the exon20i (30.8%) and L858R (29.3%) cohorts relative to the exon19del cohort (22.6%). The exon20i cohort had higher median total healthcare costs per patient per month ($27,069) relative to exon19del ($17,482) and L858R ($17,763). EGFR tyrosine kinase inhibitors (TKI) were the most frequently observed treatment type for exon19del and L858R cohorts, while chemotherapy was the most observed treatment in exon20i cohort. LIMITATIONS: The sample size for the study cohorts was small, thus no statistical comparisons were conducted. CONCLUSIONS: This is one of the first real-world studies to describe HRU and costs among a/mNSCLC patients by specific EGFR mutation type. HRU and costs varied between EGFR mutation types and were highest among exon20i cohort, potentially reflecting higher disease burden and unmet need among patients with this mutation.

Patients with non-small cell lung cancer (NSCLC) in an advanced or metastatic stage (a/mNSCLC) where cancer has spread to other parts of the body have high chance of dying within five years. Treatment and management of a/mNSCLC also incurs significant healthcare resource utilization (HRU) and costs. Patients with a/mNSCLC may have their epidermal growth factor receptor (EGFR) gene mutated with different variations. Our study described what a/mNSCLC patients were treated with, their HRU and healthcare costs separately for the following three types of EGFR mutations: exon 19 deletion (exon19del), exon 21 L858R (L858R), or exon 20 insertion (exon20i). Our study found that patients with exon19del or L858R mutation were commonly treated with EGFR tyrosine kinase inhibitors (TKIs), while exon20i patients were mostly treated with chemotherapy due to lack of targeted treatment for exon20i during the time when the study was conducted. HRU and healthcare costs were highest for patients with exon20i, which shows that patients with exon20i face high burden and have a need for new treatment options.

Machine learning-directed electrical impedance tomography to predict metabolically vulnerable plaques.

The characterization of atherosclerotic plaques to predict their vulnerability to rupture remains a diagnostic challenge. Despite existing imaging modalities, none have proven their abilities to identify metabolically active oxidized low-density lipoprotein (oxLDL), a marker of plaque vulnerability. To this end, we developed a machine learning-directed electrochemical impedance spectroscopy (EIS) platform to analyze oxLDL-rich plaques, with immunohistology serving as the ground truth. We fabricated the EIS sensor by affixing a six-point microelectrode configuration onto a silicone balloon catheter and electroplating the surface with platinum black (PtB) to improve the charge transfer efficiency at the electrochemical interface. To demonstrate clinical translation, we deployed the EIS sensor to the coronary arteries of an explanted human heart from a patient undergoing heart transplant and interrogated the atherosclerotic lesions to reconstruct the 3D EIS profiles of oxLDL-rich atherosclerotic plaques in both right coronary and left descending coronary arteries. To establish effective generalization of our methods, we repeated the reconstruction and training process on the common carotid arteries of an unembalmed human cadaver specimen. Our findings indicated that our DenseNet model achieves the most reliable predictions for metabolically vulnerable plaque, yielding an accuracy of 92.59% after 100 epochs of training.

How does the antimicrobial stewardship provider role affect prospective audit and feedback acceptance for restricted antibiotics in a Canadian tertiary-care center?

Of 731 restricted antimicrobial prescriptions subject to antimicrobial stewardship program (ASP) prospective audit and feedback (PAF) over a 3-year period, 598 PAF recommendations (82%) were fully accepted. Physician auditors had an increased odds of PAF recommendation acceptance, reinforcing the complementary role of the ASP physician in the multidisciplinary ASP team.

Outcomes Following Early Postoperative Adjuvant Radiosurgery for Brain Metastases.

Importance: Adjuvant stereotactic radiosurgery (SRS) enhances the local control of resected brain metastases (BrM). However, the risks of local failure (LF) and potential for posttreatment adverse radiation effects (PTRE) after early postoperative adjuvant SRS have not yet been established. Objective: To evaluate whether adjuvant SRS delivered within a median of 14 days after surgery is associated with improved LF without a concomitant increase in PTRE. Design, Setting, and Participants: This prospective cohort study examines a clinical workflow (RapidRT) that was implemented from 2019 to 2022 to deliver SRS to surgical patients within a median of 14 days, ensuring all patients were treated within 30 days postoperatively. This prospective cohort was compared with a historical cohort (StanRT) of patients with BrM resected between 2013 and 2019 to assess the association of the RapidRT workflow with LF and PTRE. The 2 cohorts were combined to identify optimal SRS timing, with a median follow-up of 3.3 years for survivors. Exposure: Timing of adjuvant SRS (14, 21, and 30 days postoperatively). Main Outcomes and Measures: LF and PTRE, according to modified Response Assessment in Neuro-Oncology Brain Metastases criteria. Results: There were 438 patients (265 [60.5%] female patients; 23 [5.3%] Asian, 27 [6.2%] Black, and 364 [83.1%] White patients) with a mean (SD) age of 62 (13) years; 377 were in the StanRT cohort and 61 in the RapidRT cohort. LF and PTRE rates at 1 year were not significantly different between RapidRT and StanRT cohorts. Timing of SRS was associated with radiographic PTRE. Patients receiving radiation within 14 days had the highest 1-year PTRE rate (18.08%; 95% CI, 8.31%-30.86%), and patients receiving radiation between 22 and 30 days had the lowest 1-year PTRE rate (4.10%; 95% CI, 1.52%-8.73%; P = .03). LF rates were highest for patients receiving radiation more than 30 days from surgery (10.65%; 95% CI, 6.90%-15.32%) but comparable for patients receiving radiation within 14 days, between 15 and 21 days, and between 22 and 30 days (≤14 days: 5.12%; 95% CI, 0.86%-15.60%; 15 to ≤21 days: 3.21%; 95% CI, 0.59%-9.99%; 22 to ≤30 days: 6.58%; 95% CI, 3.06%-11.94%; P = .20). Conclusions and Relevance: In this cohort study of adjuvant SRS timing following surgical resection of BrM, the optimal timing for adjuvant SRS appears to be within 22 to 30 days following surgery. The findings of this study suggest that this timing allows for a balanced approach that minimizes the risks associated with LF and PTRE.

VISGRADER: Automatic Grading of D3 Visualizations.

Manually grading D3 data visualizations is a challenging endeavor, and is especially difficult for large classes with hundreds of students. Grading an interactive visualization requires a combination of interactive, quantitative, and qualitative evaluation that are conventionally done manually and are difficult to scale up as the visualization complexity, data size, and number of students increase. We present VISGRADER, a first-of-its kind automatic grading method for D3 visualizations that scalably and precisely evaluates the data bindings, visual encodings, interactions, and design specifications used in a visualization. Our method enhances students' learning experience, enabling them to submit their code frequently and receive rapid feedback to better inform iteration and improvement to their code and visualization design. We have successfully deployed our method and auto-graded D3 submissions from more than 4000 students in a visualization course at Georgia Tech, and received positive feedback for expanding its adoption.

Long COVID and psychological distress in young adults: Potential protective effect of a prior mental health diagnosis.

BACKGROUND: Although young adulthood is a period characterized by marked psychological vulnerability, young adults are typically considered to be in good physical health and are therefore understudied with respect to the effects of COVID-19 infection and long COVID. The present study examined associations between post-acute sequelae of COVID-19 (PASC) and serious psychological distress during young adulthood, and tested whether prior mental health diagnosis moderated this association. METHODS: Participants were 44,652 young adults who completed the Spring 2022 administration of the American College Health Association-National College Health Assessment III (ACHA-NCHA). Blockwise logistic regressions tested the odds of meeting the clinical threshold for serious psychological distress. RESULTS: PASC was associated with 53 % increased likelihood of meeting the clinical threshold for serious psychological distress. Among young adults with a prior mental health diagnosis, PASC predicted 36 % increased odds of serious psychological distress; among those without a diagnosis, PASC predicted 81 % increased odds. LIMITATIONS: PASC was assessed using a single self-report item rather than a clinical diagnosis of specific symptomatology. The analyses were cross-sectional and relied on concurrent reports of PASC and psychological distress which precluded us from making claims regarding directionality of the associations. The outcome of generalized psychological distress limited us from generating targeted treatment recommendations. CONCLUSIONS: PASC may confer elevated psychological distress among young adults. The association of PASC to serious psychological distress was stronger in young adults without a mental health diagnosis than those with a diagnosis. Prior experience with mental illness may mitigate the psychological burden of long-term symptomatology.

Antimicrobial stewardship, procalcitonin testing, and rapid blood-culture identification to optimize sepsis care in critically ill adult patients: A quality improvement initiative.

We examined the effect of an antimicrobial stewardship program (ASP), procalcitonin testing and rapid blood-culture identification on hospital mortality in a prospective quality improvement project in critically ill septic adults. Secondarily, we have reported antimicrobial guideline concordance, acceptance of ASP interventions, and antimicrobial and health-resource utilization.

Molecular basis for the recognition of 24-(S)-hydroxycholesterol by integrin αvß3.

A growing body of evidence suggests that oxysterols such as 25-hydroxycholesterol (25HC) are biologically active and involved in many physiological and pathological processes. Our previous study demonstrated that 25HC induces an innate immune response during viral infections by activating the integrin-focal adhesion kinase (FAK) pathway. 25HC produced the proinflammatory response by binding directly to integrins at a novel binding site (site II) and triggering the production of proinflammatory mediators such as tumor necrosis factor-α (TNF) and interleukin-6 (IL-6). 24-(S)-hydroxycholesterol (24HC), a structural isomer of 25HC, plays a critical role in cholesterol homeostasis in the human brain and is implicated in multiple inflammatory conditions, including Alzheimer's disease. However, whether 24HC can induce a proinflammatory response like 25HC in non-neuronal cells has not been studied and remains unknown. The aim of this study was to examine whether 24HC produces such an immune response using in silico and in vitro experiments. Our results indicate that despite being a structural isomer of 25HC, 24HC binds at site II in a distinct binding mode, engages in varied residue interactions, and produces significant conformational changes in the specificity-determining loop (SDL). In addition, our surface plasmon resonance (SPR) study reveals that 24HC could directly bind to integrin αvß3, with a binding affinity three-fold lower than 25HC. Furthermore, our in vitro studies with macrophages support the involvement of FAK and NFκB signaling pathways in triggering 24HC-mediated production of TNF. Thus, we have identified 24HC as another oxysterol that binds to integrin αvß3 and promotes a proinflammatory response via the integrin-FAK-NFκB pathway.

Cationic polymer precipitation for enhanced impurity removal in downstream processing.

Precipitation can be used for the removal of impurities early in the downstream purification process of biologics, with the soluble product remaining in the filtrate through microfiltration. The objective of this study was to examine the use of polyallylamine (PAA) precipitation to increase the purity of product via higher host cell protein removal to enhance polysorbate excipient stability to enable a longer shelf life. Experiments were performed using three monoclonal antibodies (mAbs) with different properties of isoelectric point and IgG subclass. High throughput workflows were established to quickly screen precipitation conditions as a function of pH, conductivity and PAA concentrations. Process analytical tools (PATs) were used to evaluate the size distribution of particles and inform the optimal precipitation condition. Minimal pressure increase was observed during depth filtration of the precipitates. The precipitation was scaled up to 20L size and the extensive characterization of precipitated samples after protein A chromatography showed >75% reduction of host cell protein (HCP) concentrations (by ELISA), >90% reduction of number of HCP species (by mass spectrometry), and >99.8% reduction of DNA. The stability of polysorbate containing formulation buffers for all three mAbs in the protein A purified intermediates was improved at least 25% after PAA precipitation. Mass spectrometry was used to obtain additional understanding of the interaction between PAA and HCPs with different properties. Minimal impact on product quality and <5% yield loss after precipitation were observed while the residual PAA was <9 ppm. These results expand the toolbox in downstream purification to solve HCP clearance issues for programs with purification challenges, while also providing important insights into the integration of precipitation-depth filtration and the current platform process for the purification of biologics.

Low-Dose TMP-SMX for Pneumocystis jirovecii Pneumonia Prophylaxis in Pediatric Solid Organ Transplant Recipients.

OBJECTIVE: Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection that adversely affects solid organ transplant (SOT) recipients. Published guidelines endorse 5 to 10 mg/kg/day (trimethoprim component) trimethoprim-sulfamethoxazole (TMP-SMX) as the recommended regimen for PJP prevention, often resulting in drug-related adverse effects. We investigated the use of a low-dose TMP-SMX regimen given at 2.5 mg/kg/dose once daily every Monday, Wednesday, and Friday at a large pediatric transplantation center. METHODS: A retrospective chart review was conducted, including patients ages 0 to 21 years who underwent SOT from January 1, 2012, to May 1, 2020, and who were subsequently started on PJP prophylaxis with low-dose TMP-SMX for a minimum of 6 months. The primary end point was the incidence of breakthrough PJP infection on the low-dose TMP-SMX regimen. Secondary end points include the prevalence of adverse effects characteristic of TMP-SMX. RESULTS: A total of 234 patients were included in this study, and 6 of 234 patients (2.6%) were empirically transitioned to treatment dosing of TMP-SMX given a clinical concern for PJP, although none received a diagnosis of PJP. There were 7 patients (2.6%) who experienced hyperkalemia, 36 (13.3%) had neutropenia, and 22 (8.1%) had thrombocytopenia (all grade 4). Clinically significant serum creatinine elevations were seen in 43 of 271 patients (15.9%). Elevations of liver enzymes were seen in 16 of 271 patients (5.9%). Rash was documented in 4 of 271 patients (1.5%). CONCLUSIONS: In our patient cohort, low-dose TMP-SMX preserves the efficacy of PJP prophylaxis while providing an acceptable adverse effect profile.

A Rare Case of Skin Necrosis Following Extravasation of Prothrombin Complex Concentrate (PCC) Infusion During Warfarin Reversal.

Warfarin-induced skin necrosis is a well-documented complication that can occur following commencement of warfarin. However, skin necrosis following extravasation of prothrombin complex concentrate (PCC) infusion is a very rare adverse event that is not commonly documented. This case illustrates the possibility of developing skin necrosis following the administration of an anticoagulation reversal agent rather than from anticoagulation itself. We report a case of a 58-year-old male who developed skin necrosis at the site of PCC infusion in the right upper extremity (RUE) for warfarin reversal of an elevated international normalized ratio (INR). The skin necrosis progressed into a full thickness chemical burn. As a result, the patient underwent allograft followed by split thickness autograft and RECELL placement. This case presentation describes the first reported case of skin necrosis following extravasation of PCC infusion during warfarin reversal.