Rare variant of large pediatric glioneuronal tumor with novel MYO5A::NTRK3 fusion: illustrative case

BACKGROUND

Glioneuronal tumors (GNTs) comprise a rare class of central nervous system (CNS) neoplasms with varying degrees of neuronal and glial differentiation that predominately affect children and young adults. Within the current 2021 World Health Organization (WHO) classification of CNS tumors, GNTs encompass 14 distinct tumor types. Recently, the use of whole-genome DNA methylation profiling has allowed more precise classification of this tumor group.

OBSERVATIONS

A 3-year-old male presented with a 3-month history of increasing head circumference, regression of developmental milestones, and speech delay. Magnetic resonance imaging of the brain was notable for a large left hemispheric multiseptated mass with significant mass effect and midline shift that was treated with near-total resection. Histological and molecular assessment demonstrated a glioneuronal tumor harboring an MYO5A::NTRK3 fusion. By DNA methylation profiling, this tumor matched to a provisional methylation class known as "glioneuronal tumor kinase-fused" (GNT kinase-fused). The patient was later started on targeted therapy with larotrectinib.

LESSONS

This is the first report of an MYO5A::NTRK3 fusion in a pediatric GNT. GNT kinase-fused is a provisional methylation class not currently included in the WHO classification of CNS tumors. This case highlights the impact of thorough molecular characterization of CNS tumors, especially with the increasing availability of novel gene targeting therapies.

CYSTEINE-RICH DOMAIN OF TYPE III COLLAGEN N-PROPEPTIDE INHIBITS FIBROBLAST ACTIVATION BY ATTENUATING TGFβ SIGNALING

TGFβ is a key regulator of the dynamic reciprocity between cells and the extracellular matrix that drives physiologic and pathologic responses in both tissue repair and tumor microenvironments. Our studies define type III Collagen (Col3) as a suppressor of scar formation and desmoplasia through its effects, in part, on myofibroblasts. TGFβ stimulates activation of myofibroblasts, and here, we demonstrate that cultured Col3-deficient fibroblasts have increased TGFβ signaling compared to wild-type fibroblasts. Moreover, kinetic binding studies show that a synthetic peptide containing a Col3 cysteine-rich (CR) domain found within its N-propeptide binds in a dose-dependent manner to TGFβ1, while a CR control peptide with mutated cysteines does not, suggesting that Col3 attenuates TGFβ signaling in part through the N-propeptide CR domain. Consistent with this hypothesis, the CR peptide attenuates TGFβ signaling in fibroblasts and 4T1 breast cancer cells and suppresses fibroblast activation and contraction, as assessed by α-smooth-muscle actin staining, cell wrinkling of deformable silicone, and stressed-fibroblast populated collagen lattice contraction assays. Finally, CR peptide treatment of orthotopically injected breast cancer cells (4T1) suppresses intratumoral fibroblast activation and inhibits primary tumor growth compared to CR control. Treatment with the CR peptide decreases both intratumoral canonical and non-canonical downstream TGFβ signaling targets, consistent with its extracellular binding to TGFβ. Taken together, our results suggest that the Col3 N-propeptide CR domain binds TGFβ1 and attenuates (but importantly does not eliminate) TGFβ signaling in fibroblasts and cancer cells. Expanding on our previous work, this study demonstrates an additional mechanism by which Col3 regulates cell behaviors in post-injury and tumor microenvironments and suggests that novel Col3-targeted strategies could effectively control biologic responses in vivo and improve anti-scarring/fibrosis and oncologic therapies.

Pulmonary Leukosequestration without Hypoxemia during Hemodialysis

Dialysis-associated hypoxemia is frequently of clinically significant magnitude and is incompletely understood. In order to investigate the hypoxemia directly we labelled a patient's white blood cells with 111Indium-oxine prior to hemodialysis with acetate or bicarbonate baths. Both dialysate buffers were associated with similar degrees of early peripheral neutropenia, complement activation and elevation of lactoferrin levels, with simultaneous lung localization of radionuclide activity. However, there was not widening of the alveolar to arterial oxygen gradient, or increased wasted ventilatory fraction during this early time period. Significant hypoxemia occurred later in the dialysis, was associated with a decreased respiratory exchange ratio and only occurred with the acetate dialysate buffer. Thus, initial pulmonary leukosequestration was documented but did not have an adverse impact on gas exchange. Hypoxemia during acetate dialysis occurred instead as a consequence of alveolar hypoventilation.

Cyclooctyne-based reagents for uncatalyzed click chemistry: A computational survey

With the goal of identifying alkyne-like reagents for use in click chemistry, but without Cu catalysts, we used B3LYP density function theory (DFT) to investigate the trends in activation barriers for the 1,3-dipolar cycloadditions of azides with various cyclooctyne, dibenzocyclooctyne, and azacyclooctyne compounds. Based on these trends, we find monobenzocyclooctyne-based reagents that are predicted to have dramatically improved reactivity over currently employed reagents.

The economic cost of environmental factors among North Carolina children living in substandard housing

OBJECTIVES

We quantified the economic cost of selected environmental factors among North Carolina children living in substandard housing.

METHODS

We gathered data on direct medical care costs for specific childhood medical conditions associated with environmental factors commonly found in substandard housing. Medical claims data for 2006 and 2007 were obtained from BlueCross BlueShield of North Carolina and the North Carolina Department of Health and Human Services. Indirect costs were based in part on nonmedical data obtained from several previous studies.

RESULTS

Total (direct and indirect) costs for the conditions assessed exceeded $92 million in 2006 and $108 million in 2007. Neurobehavioral conditions contributed to more than 52% of all costs, followed by lead poisoning (20%) and respiratory conditions (12%). Neurobehavioral conditions were the largest contributor to direct medical costs (44%), followed by respiratory conditions (38%) and accidental burns and falls (10%).

CONCLUSIONS

Direct and indirect costs associated with environmental factors appear to be increasing at about twice the rate of medical inflation. More aggressive policies and funding are needed to reduce the substantial financial impact of childhood illnesses associated with substandard housing in North Carolina.

A Benefit???Cost Analysis of a Worksite Nurse Practitioner Program: First Impressions

OBJECTIVE

This study aimed to assess the initial impact of an on-site nurse practitioner (NP) initiative on the health care costs (HCC) among 4,284 employees and their dependents.

METHODS

The authors analyzed HCC by two methods. First, they compared annualized actual values for the first 6 months of the startup year (2004) with those projected for 2004 on the basis of claims paid in 2002 and 2003. Both aggregate and per-individual HCC were used as the basis for comparison. The difference in HCC between projected and observed values for 2004 was defined as the benefit of the NP program. In a second analysis, HCC were calculated using 2003 paid claims for major diagnostic categories (MDC). These HCC were compared with those that would have been incurred had off-site care been used for the (annualized) number of such patients cared for by the NP in 2004 with the same MDC. The cost of the NP program was used as the denominator in calculating the benefit-to-cost ratio using the savings in HCC estimated by the two previously mentioned methods.

RESULTS

Annualized cost of the NP program was 82,716 dollars. Savings in HCC using the first method were 1,313,756 dollars per year, yielding a benefit-to-cost ratio of 15 to 1. Using the MDC analysis, the ratio was 2.4 to 1. This difference in ratios between the two estimates may partly be attributable to effects of other initiatives such as the wellness program and the Nurse Health Line. The latter was begun 10 weeks before the NP program, is available at all times, and is intended to minimize the need for workers and families to seek high-cost care at hospital emergency departments.

CONCLUSIONS

The first 6 months of a new NP initiative yielded substantial reductions in HCC that warrant further analysis over longer periods of observation. However, the initial estimates may understate the aggregate value of the program because it may also reduce on-site injury and illness patterns and improve productivity, end points that were not assessed in this initial snapshot.

The medical cost of high serum cholesterol in Harris County, Texas

High serum cholesterol levels are common among Texans, especially in the greater Houston metropolitan area (Harris County) where such levels are almost 50% higher than the national norm. By using actual medical care claims and cost data, an analysis was conducted to determine the direct medical care cost of high serum cholesterol tied to selected cardiovascular conditions in Harris County. As part of conducting the analysis, Health Management Associates obtained prevalence rates of Harris County residents with elevated cholesterol levels, actual inpatient cardiovascular claims and costs, and estimated outpatient cardiovascular claims and costs. The financial cost analysis of high cholesterol revealed that more than 25 million dollars was spent alone on selected cardiovascular conditions. This estimate is conservative because it did not factor in all types of cardiovascular claims associated with high serum cholesterol, did not factor in other (noncardiovascular) claims that may be associated with high serum cholesterol, and did not include indirect costs such as absenteeism, lost productivity, and medication costs associated with the selected conditions. As Harris County is home to approximately 1 of every 5 adults in Texas, extrapolating the county's direct costs for high serum cholesterol to the entire state would translate into a direct medical care tab of more than 120 million dollars.

The cost of being couch potato

The scientific evidence is clear--regular physical activity has powerful positive effects on both physical and psychological health. Conversely, physical inactivity has a high human cost in terms of health. It shortens years of life, decreases quality of life, and limits functional independence. These health effects arise from physical inactivity's contribution to cardiovascular disease, obesity, diabetes, osteoporosis, mental health disorders, and some cancers (i.e., colon and breast).

Nafamstat mesilate attenuates pulmonary hypertension in heparin-protamine reactions

Rapid protamine reversal of heparin anticoagulation in awake sheep caused, after 1 min, a approximately 15-fold increase of arterial plasma thromboxane B2 (TxB2) levels, a 4-fold rise of pulmonary vascular resistance (PVR), a 2-fold rise of pulmonary arterial pressure, and after 3 min, a 2-fold rise of ovine arterial plasma complement C3a levels (P less than 0.05). Infusion of nafamstat mesilate (FUT-175), a protease and complement pathway inhibitor, before protamine reduced these increases by approximately 60-90% (P less than 0.05). FUT-175 did not modify heparin + protamine-induced leukopenia, suggesting that FUT-175 incompletely blocked C5a production. We also learned that infusing protamine first and heparin 5 min later did not increase either plasma C3a or TxB2 levels or PVR while the activated clotting time increased only minimally. Thus, in awake sheep, the sequence of heparin and protamine infusion influences complement activation and pulmonary vasoconstriction. FUT-175 pretreatment reduces thromboxane release and pulmonary vasoconstriction probably by limiting complement activation.

Nurses' intervention in specific risk factors in high risk employees. An economic appraisal

1. Occupational health nurses can lower employees' health risks through appropriate screening, education, and monitoring efforts at the worksite. 2. In addition to health promotion as well as benefits education, influencing the demand for health care, creating cost efficient services, and informing employees on how, when, and why to use cost efficient health care services, are the foundations for successful health care cost management. 3. To respond to growing accountability issues, nurses need to quantitatively evaluate the overall impact of their efforts on employees' health status and corporate health care costs. 4. The occupational health nurse can be an effective health care cost manager by using appropriate strategies and resources consistently.

Identification of the C5a des Arg cochemotaxin. Homology with vitamin D-binding protein (group-specific component globulin)

The chemotactic activity of human C5a des Arg is enhanced significantly by an anionic polypeptide (cochemotaxin) in normal human serum and plasma. The cochemotaxin attaches to sialic acid residues within the oligosaccharide chain of native C5a des Arg to form a complex with potent chemotactic activity for human PMN. We investigated the nature of the cochemotaxin and found that vitamin D-binding protein is the putative cochemotaxin. Vitamin D-binding protein enhanced the chemotactic activity of native C5a des Arg, but had no effect on the chemotactic activity of either native C5a or FMLP. Sialic acid prevented both enhancement by vitamin D-binding protein of the chemotactic activity of native C5a des Arg and formation of C5a des Arg-vitamin D-binding protein complexes, detected by molecular sieve chromatography. Furthermore, vitamin D-binding protein and cochemotaxin exhibited identical molecular weights, isoelectric points, antigenic reactivity, and amino acid composition.

Pulmonary leukosequestration without hypoxemia during hemodialysis

Dialysis-associated hypoxemia is frequently of clinically significant magnitude and is incompletely understood. In order to investigate the hypoxemia directly we labelled a patient's white blood cells with 111Indium-oxine prior to hemodialysis with acetate or bicarbonate baths. Both dialysate buffers were associated with similar degrees of early peripheral neutropenia, complement activation and elevation of lactoferrin levels, with simultaneous lung localization of radionuclide activity. However, there was not widening of the alveolar to arterial oxygen gradient, or increased wasted ventilatory fraction during this early time period. Significant hypoxemia occurred later in the dialysis, was associated with a decreased respiratory exchange ratio and only occurred with the acetate dialysate buffer. Thus, initial pulmonary leukosequestration was documented but did not have an adverse impact on gas exchange. Hypoxemia during acetate dialysis occurred instead as a consequence of alveolar hypoventilation.