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1.
Br J Haematol ; 204(1): 229-239, 2024 01.
Article in English | MEDLINE | ID: mdl-37871900

ABSTRACT

Therapeutic management and prognostication for patients with B-acute lymphoblastic leukaemia (B-ALL) require appropriate disease subclassification. BCR::ABL1-like B-ALL is unique in that it is defined by a gene expression profile similar to BCR::ABL1+ B-ALL rather than a unifying recurrent translocation. Current molecular/cytogenetic techniques to identify this subtype are expensive, not widely accessible, have long turnaround times and/or require an adequate liquid biopsy. We have studied a total of 118 B-ALL cases from three institutions in two laboratories to identify surrogates for BCR::ABL1+/like B-ALL. We report that immunoglobulin joining chain (IGJ) and spermatogenesis associated serine-rich 2-like (SPATS2L) immunohistochemistry (IHC) sensitively and specifically identify BCR::ABL1+/like B-ALL. IGJ IHC positivity has a sensitivity of 83%, a specificity of 95%, a positive predictive value (PPV) of 89% and a negative predictive value (NPV) of 90%. SPATS2L staining has similar sensitivity and NPV but lower specificity (85%) and PPV (70%). The presence of either IGJ or SPATS2L staining augments the sensitivity (93%) and NPV (95%). While these findings would need to be validated in larger studies, they suggest that IGJ and/or SPATS2L IHC may be utilized in identifying BCR::ABL1-like B-ALL or in selecting B-ALL cases for confirmatory molecular/genetic testing, particularly in resource-limited settings.


Subject(s)
Precursor B-Cell Lymphoblastic Leukemia-Lymphoma , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Male , Humans , Immunohistochemistry , Fusion Proteins, bcr-abl/genetics , Fusion Proteins, bcr-abl/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Translocation, Genetic
2.
Cancers (Basel) ; 15(23)2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38067330

ABSTRACT

Mast cell disorders range from benign proliferations to systemic diseases that cause anaphylaxis and other diverse symptoms to mast cell neoplasms with varied clinical outcomes. Mastocytosis is the pathologic process of the accumulation of abnormal mast cells in different organs, mostly driven by KIT mutations, and can present as cutaneous mastocytosis, systemic mastocytosis (SM), and mast cell sarcoma. The WHO 5th edition classification divides systemic mastocytosis into bone marrow mastocytosis, indolent systemic mastocytosis, smoldering systemic mastocytosis, aggressive systemic mastocytosis, systemic mastocytosis with an associated hematologic neoplasm, and mast cell leukemia. The new ICC classifies SM slightly differently. The diagnosis of SM requires the integration of bone marrow morphologic, immunophenotypic, and molecular findings, as well as clinical signs and symptoms. Moreover, understanding the wide range of clinical presentations for patients with mast cell disorders is necessary for accurate and timely diagnosis. This review provides an updated overview of mast cell disorders, with a special emphasis on SM, including the latest approaches to diagnosis, prognostic stratification, and management of this rare disease.

4.
Case Rep Hematol ; 2023: 8833273, 2023.
Article in English | MEDLINE | ID: mdl-38028985

ABSTRACT

While the Epstein-Barr virus (EBV) is known to drive de novo lymphomagenesis, it may rarely contribute to transformation of indolent lymphoma as well. Some EBV-related lymphomas represent a diagnostic challenge with important prognostic and therapeutic implications. We describe a case of follicular lymphoma (FL) transformation to both EBV + diffuse large B-cell lymphoma (DLBCL) and EBV + classic Hodgkin lymphoma (cHL), the latter of which was only identified retrospectively after selective outgrowth during DLBCL therapy. Finally, we describe successful salvage therapy with brentuximab vedotin plus nivolumab. This is the first known case of composite lymphoma with FL, EBV + DLBCL, and EBV + cHL within a single lymph node. The disease course highlights the importance of careful morphologic examination and comprehensive immunophenotypic characterization of EBV + lymphomas to ensure proper clinical care and underscores the potential for novel therapies currently under investigation. This trial is registered with NCT01671813.

5.
Phys Rev Lett ; 130(13): 137401, 2023 Mar 31.
Article in English | MEDLINE | ID: mdl-37067312

ABSTRACT

The eigenvalue spectrum of a random matrix often only depends on the first and second moments of its elements, but not on the specific distribution from which they are drawn. The validity of this universality principle is often assumed without proof in applications. In this Letter, we offer a pertinent counterexample in the context of the generalized Lotka-Volterra equations. Using dynamic mean-field theory, we derive the statistics of the interactions between species in an evolved ecological community. We then show that the full statistics of these interactions, beyond those of a Gaussian ensemble, are required to correctly predict the eigenvalue spectrum and therefore stability. Consequently, the universality principle fails in this system. We thus show that the eigenvalue spectra of random matrices can be used to deduce the stability of "feasible" ecological communities, but only if the emergent non-Gaussian statistics of the interactions between species are taken into account.

6.
Sci Signal ; 15(765): eabl6781, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36538593

ABSTRACT

Pyroptosis is a mechanism of programmed, necrotic cell death mediated by gasdermins, a family of pore-forming proteins. Caspase-1 activates gasdermin D (GSDMD) under inflammatory conditions, whereas caspase-3 activates GSDME under apoptotic conditions, such as those induced by chemotherapy. These pathways are thought to be separate. However, we found that they are part of an integrated network of gatekeepers that enables pyroptotic cell death. We observed that GSDMD was the primary pyroptotic mediator in cultured blood cells in response to doxorubicin and etoposide, two common chemotherapies for hematopoietic malignancies. Upon treatment, the channel protein pannexin-1 (PANX1), which is stimulated by the initiation of apoptosis, increased membrane permeability to induce K+ efflux-driven activation of the NLRP3 inflammasome and GSDMD. However, either PANX1 or GSDME could also be the primary mediator of chemotherapy-induced pyroptosis when present at higher amounts. The most abundant pore-forming protein in acute myeloid leukemias from patients predicted the cell death pathway in response to chemotherapy. This interconnected network, a multistep switch that converts apoptosis to pyroptosis, could be clinically titratated to modulate cell death with regard to antitumor immunity or tumor lysis syndrome in patients.


Subject(s)
Antineoplastic Agents , Hematologic Neoplasms , Humans , Gasdermins , Intracellular Signaling Peptides and Proteins/metabolism , Apoptosis , Necrosis , Inflammasomes/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Connexins/genetics , Connexins/metabolism
7.
Hum Pathol ; 125: 108-116, 2022 07.
Article in English | MEDLINE | ID: mdl-35472399

ABSTRACT

Monoclonal B-cell lymphocytosis is a clonal B-cell population in the peripheral blood (PB) of <5x10ˆ9/L without extramedullary (EM) disease, often with a chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) phenotype. The degree of bone marrow (BM) involvement is not currently a part of the diagnostic criteria for MBL or CLL/SLL, but CLL-type MBLs in BM can be seen in patients lacking PB lymphocytosis. Data are limited on the outcome of such cases. We assessed the clinicopathologic characteristics of isolated BM CLL-type MBL in patients who did not meet criteria for CLL/SLL. We evaluated BMs from 2006 to 2018 with CLL-like clonal B-cell populations in patients with a PB absolute lymphocyte count or monoclonal B-cell count of <5 × 109/L and without definite evidence of EM disease. We investigated the extent and pattern of marrow involvement, PB counts, flow cytometric data, genetics, concurrent hematopoietic diseases, and outcomes including progression and treatment. Thirty cases with BM MBL but <5x10E9/L PB monoclonal B cells and no EM disease were identified. Thirteen of 30 had additional hematopoietic neoplasms. The mean patient age was 74.1 years (median: 77 years, range: 43-91 years). No patients had lymphadenopathy (LAD) or splenomegaly by physical examination. By imaging, nine of 18 had LAD (8/9 < 1.5 cm) and four of 18 had splenomegaly but with other attributable etiologies. Mean PB absolute lymphocyte count (ALC) was 1.8×10E9/L (range: 0.5-5.0×10E9/L). Twenty-four of 30 (80%) had low-level (<20%) BM involvement by MBL, and among these, none with available follow-up data progressed to diagnostic CLL/SLL. Six of 30 (20%) had >20% marrow involvement by MBL. Four of 6 were treated for CLL/SLL due to cytopenias, despite not meeting diagnostic criteria, and all 4 were CD38 or ZAP70 positive and had cytogenetic abnormalities, including trisomy 12. One of 6 developed overt CLL/SLL 3 years later and had cytogenetic abnormalities at the time of MBL diagnosis. One of 6 was monitored without treatment but had no cytogenetic abnormalities.Isolated BM CLL-type MBL represents a diagnostic gray area, and this study highlights the range of clinical outcomes. All cases with <20% BM involvement did not require CLL-specific treatment or progress to CLL/SLL. In the 4 cases where treatment was initiated due to cytopenias, patients had ≥20% BM involvement, CD38 or ZAP70 expression, and cytogenetic abnormalities but lacked a PB ALC of ≥5x10E9/L or LAD ≥1.5 cm, suggesting that not all patients with clinically significant disease will meet criteria for CLL/SLL. The results also show that concurrent hematopoietic disorders can complicate the diagnosis, as the disease course or treatment may result in leukopenia, precluding PB absolute lymphocytosis. Though larger studies are needed, the degree of BM involvement, in conjunction with flow cytometric prognostic markers, and cytogenetic abnormalities may be a useful addition to the current diagnostic criteria for CLL/SLL which only considers a PB numerical cutoff and EM involvement.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell , Lymphocytosis , Lymphoma, B-Cell , Neoplasms, Plasma Cell , Precancerous Conditions , Bone Marrow/pathology , Chromosome Aberrations , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Lymphocytosis/diagnosis , Lymphocytosis/pathology , Lymphoma, B-Cell/pathology , Splenomegaly
8.
Phys Rev Lett ; 128(12): 120601, 2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35394295

ABSTRACT

Random matrix theory allows one to deduce the eigenvalue spectrum of a large matrix given only statistical information about its elements. Such results provide insight into what factors contribute to the stability of complex dynamical systems. In this Letter, we study the eigenvalue spectrum of an ensemble of random matrices with correlations between any pair of elements. To this end, we introduce an analytical method that maps the resolvent of the random matrix onto the response functions of a linear dynamical system. The response functions are then evaluated using a path integral formalism, enabling us to make deductions about the eigenvalue spectrum. Our central result is a simple, closed-form expression for the leading eigenvalue of a large random matrix with generalized correlations. This formula demonstrates that correlations between matrix elements that are not diagonally opposite, which are often neglected, can have a significant impact on stability.

9.
J Mol Biol ; 434(4): 167183, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-34358546

ABSTRACT

Pyroptosis, a lytic form of programmed cell death, both stimulates effective immune responses and causes tissue damage. Gasdermin (GSDM) proteins are a family of pore-forming executors of pyroptosis. While the most-studied member, GSDMD, exerts critical functions in inflammasome biology, emerging evidence demonstrates potential broad relevance for GSDM-mediated pyroptosis across diverse pathologies. In this review, we describe GSDM biology, outline conditions where inflammasomes and GSDM-mediated pyroptosis represent rational therapeutic targets, and delineate strategies to manipulate these central immunologic processes for the treatment of human disease.


Subject(s)
Inflammasomes , Molecular Targeted Therapy , Phosphate-Binding Proteins , Pore Forming Cytotoxic Proteins , Pyroptosis , Humans , Inflammasomes/metabolism , Phosphate-Binding Proteins/metabolism , Pore Forming Cytotoxic Proteins/metabolism , Pyroptosis/drug effects
10.
Ann Emerg Med ; 75(5): 559-567, 2020 05.
Article in English | MEDLINE | ID: mdl-31983499

ABSTRACT

STUDY OBJECTIVE: Out-of-hospital naloxone has been championed as a lifesaving solution during the opioid epidemic. However, the long-term outcomes of out-of-hospital naloxone recipients are unknown. The objectives of this study are to describe the 1-year mortality of presumed opioid overdose victims identified by receiving out-of-hospital naloxone and to determine which patient factors are associated with subsequent mortality. METHODS: This was a regional retrospective cohort study of out-of-hospital records from 7 North Carolina counties from January 1, 2015 to February 28, 2017. Patients who received out-of-hospital naloxone were included. Out-of-hospital providers subjectively assessed patients for improvement after administering naloxone. Naloxone recipients were cross-referenced with the North Carolina death index to examine mortality at days 0, 1, 30, and 365. Naloxone recipient mortality was compared with the age-adjusted, at-large population's mortality rate in 2017. Generalized estimating equations and Cox proportional hazards models were used to assess for mortality-associated factors. RESULTS: Of 3,085 out-of-hospital naloxone encounters, 72.7% of patients (n=2,244) improved, whereas 27.3% (n=841) had no improvement with naloxone. At day 365, 12.0% (n=269) of the improved subgroup, 22.6% (n=190) of the no improvement subgroup, and 14.9% (n=459) of the whole population were dead. Naloxone recipients who improved were 13.2 times (95% confidence interval 13.0 to 13.3) more likely to be dead at 1 year than a member of the general populace after age adjusting of the at-large population to match this study population. Older age and being black were associated with 1-year mortality, whereas sex and multiple overdoses were not. CONCLUSION: Opioid overdose identified by receiving out-of-hospital naloxone with clinical improvement carries a 13-fold increase in mortality compared to the general population. This suggests that this is a high-risk population that deserves attention from public health officials, policymakers, and health care providers in regard to the development of long-term solutions.


Subject(s)
Analgesics, Opioid/poisoning , Drug Overdose/drug therapy , Emergency Medical Services , Mortality/trends , Naloxone/therapeutic use , Narcotic Antagonists/therapeutic use , Adolescent , Adult , Child , Child, Preschool , Drug Overdose/mortality , Female , Humans , Infant , Infant, Newborn , Life Support Care/methods , Male , Middle Aged , North Carolina/epidemiology , Proportional Hazards Models , Retrospective Studies , Young Adult
11.
Cell Mol Life Sci ; 75(15): 2695-2718, 2018 08.
Article in English | MEDLINE | ID: mdl-29725697

ABSTRACT

The dynamic and stringent coordination of kinase and phosphatase activity controls a myriad of physiologic processes. Aberrations that disrupt the balance of this interplay represent the basis of numerous diseases. For a variety of reasons, early work in this area portrayed kinases as the dominant actors in these signaling events with phosphatases playing a secondary role. In oncology, these efforts led to breakthroughs that have dramatically altered the course of certain diseases and directed vast resources toward the development of additional kinase-targeted therapies. Yet, more recent scientific efforts have demonstrated a prominent and sometimes driving role for phosphatases across numerous malignancies. This maturation of the phosphatase field has brought with it the promise of further therapeutic advances in the field of oncology. In this review, we discuss the role of phosphatases in the regulation of cellular proliferation and survival signaling using the examples of the MAPK and PI3K/AKT pathways, c-Myc and the apoptosis machinery. Emphasis is placed on instances where these signaling networks are perturbed by dysregulation of specific phosphatases to favor growth and persistence of human cancer.


Subject(s)
Cell Proliferation , Neoplasms/metabolism , Phosphoric Monoester Hydrolases/metabolism , Signal Transduction , Apoptosis , Cell Survival , Humans , Neoplasms/pathology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism
12.
Phys Rev Lett ; 120(8): 086801, 2018 Feb 23.
Article in English | MEDLINE | ID: mdl-29542991

ABSTRACT

The crystal orientation of an exfoliated black phosphorous flake is determined by purely electrical means. A sequence of three resistance measurements on an arbitrarily shaped flake with five contacts determines the three independent components of the anisotropic in-plane resistivity tensor, thereby revealing the crystal axes. The resistivity anisotropy ratio decreases linearly with increasing temperature T and carrier density reaching a maximum ratio of 3.0 at low temperatures and densities, while mobility indicates impurity scattering at low T and acoustic phonon scattering at high T.

13.
Adv Mater ; 29(35)2017 Sep.
Article in English | MEDLINE | ID: mdl-28722239

ABSTRACT

ReS2 represents a different class of 2D materials, which is characterized by low symmetry having 1D metallic chains within the planes and extremely weak interlayer bonding. Here, the thermal conductivity of single-crystalline ReS2 in a distorted 1T phase is determined at room temperature for the in-plane directions parallel and perpendicular to the Re-chains, and the through-plane direction using time-domain thermoreflectance. ReS2 is prepared in the form of flakes having thicknesses of 60-450 nm by micromechanical exfoliation, and their crystalline orientations are identified by polarized Raman spectroscopy. The in-plane thermal conductivity is higher along the Re-chains, (70 ± 18) W m-1 K-1 , as compared to transverse to the chains, (50 ± 13) W m-1 K-1 . As expected from the weak interlayer bonding, the through-plane thermal conductivity is the lowest observed to date for 2D materials, (0.55 ± 0.07) W m-1 K-1 , resulting in a remarkably high anisotropy of (130 ± 40) and (90 ± 30) for the two in-plane directions. The thermal conductivity and interface thermal conductance of ReS2 are discussed relative to the other 2D materials.

14.
J Phys Chem Lett ; 8(7): 1343-1350, 2017 Apr 06.
Article in English | MEDLINE | ID: mdl-28266862

ABSTRACT

Black phosphorus (BP) is a layered semiconductor that recently has been the subject of intense research due to its novel electrical and optical properties, which compare favorably to those of graphene and the transition metal dichalcogenides. In particular, BP has a direct bandgap that is thickness-dependent and highly anisotropic, making BP an interesting material for nanoscale optical and optoelectronic applications. Here, we present a study of the anisotropic third-harmonic generation (THG) in exfoliated BP using a fast scanning multiphoton characterization method. We find that the anisotropic THG arises directly from the crystal structure of BP. We calculate the effective third-order susceptibility of BP to be ∼1.64 × 10-19 m2 V-2. Further, we demonstrate that multiphoton microscopy can be used for rapid, large-area characterization indexing of the crystallographic orientations of many exfoliated BP flakes from one set of multiphoton images. This method is therefore beneficial for samples of areas ∼1 cm2 in future investigations of the properties and growth of BP.

15.
Nat Chem ; 8(6): 597-602, 2016 06.
Article in English | MEDLINE | ID: mdl-27219705

ABSTRACT

Functionalization of atomically thin nanomaterials enables the tailoring of their chemical, optical and electronic properties. Exfoliated black phosphorus (BP)-a layered two-dimensional semiconductor-exhibits favourable charge-carrier mobility, tunable bandgap and highly anisotropic properties, but it is chemically reactive and degrades rapidly in ambient conditions. Here we show that covalent aryl diazonium functionalization suppresses the chemical degradation of exfoliated BP even after three weeks of ambient exposure. This chemical modification scheme spontaneously forms phosphorus-carbon bonds, has a reaction rate sensitive to the aryl diazonium substituent and alters the electronic properties of exfoliated BP, ultimately yielding a strong, tunable p-type doping that simultaneously improves the field-effect transistor mobility and on/off current ratio. This chemical functionalization pathway controllably modifies the properties of exfoliated BP, and thus improves its prospects for nanoelectronic applications.

16.
Proc Natl Acad Sci U S A ; 113(42): 11688-11693, 2016 10 18.
Article in English | MEDLINE | ID: mdl-27092006

ABSTRACT

Understanding and exploiting the remarkable optical and electronic properties of phosphorene require mass production methods that avoid chemical degradation. Although solution-based strategies have been developed for scalable exfoliation of black phosphorus, these techniques have thus far used anhydrous organic solvents in an effort to minimize exposure to known oxidants, but at the cost of limited exfoliation yield and flake size distribution. Here, we present an alternative phosphorene production method based on surfactant-assisted exfoliation and postprocessing of black phosphorus in deoxygenated water. From comprehensive microscopic and spectroscopic analysis, this approach is shown to yield phosphorene dispersions that are stable, highly concentrated, and comparable to micromechanically exfoliated phosphorene in structure and chemistry. Due to the high exfoliation efficiency of this process, the resulting phosphorene flakes are thinner than anhydrous organic solvent dispersions, thus allowing the observation of layer-dependent photoluminescence down to the monolayer limit. Furthermore, to demonstrate preservation of electronic properties following solution processing, the aqueous-exfoliated phosphorene flakes are used in field-effect transistors with high drive currents and current modulation ratios. Overall, this method enables the isolation and mass production of few-layer phosphorene, which will accelerate ongoing efforts to realize a diverse range of phosphorene-based applications.

17.
ACS Nano ; 10(4): 3900-17, 2016 04 26.
Article in English | MEDLINE | ID: mdl-27018800

ABSTRACT

Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs) and black phosphorus (BP) have beneficial electronic, optical, and physical properties at the few-layer limit. As atomically thin materials, 2D TMDCs and BP are highly sensitive to their environment and chemical modification, resulting in a strong dependence of their properties on substrate effects, intrinsic defects, and extrinsic adsorbates. Furthermore, the integration of 2D semiconductors into electronic and optoelectronic devices introduces unique challenges at metal-semiconductor and dielectric-semiconductor interfaces. Here, we review emerging efforts to understand and exploit chemical effects to influence the properties of 2D TMDCs and BP. In some cases, surface chemistry leads to significant degradation, thus necessitating the development of robust passivation schemes. On the other hand, appropriately designed chemical modification can be used to beneficially tailor electronic properties, such as controlling doping levels and charge carrier concentrations. Overall, chemical methods allow substantial tunability of the properties of 2D TMDCs and BP, thereby enabling significant future opportunities to optimize performance for device applications.

18.
Nano Lett ; 16(4): 2580-5, 2016 Apr 13.
Article in English | MEDLINE | ID: mdl-26950174

ABSTRACT

Black phosphorus (BP) has recently emerged as a promising narrow band gap layered semiconductor with optoelectronic properties that bridge the gap between semimetallic graphene and wide band gap transition metal dichalcogenides such as MoS2. To date, BP field-effect transistors have utilized a lateral geometry with in-plane transport dominating device characteristics. In contrast, we present here a vertical field-effect transistor geometry based on a graphene/BP van der Waals heterostructure. The resulting device characteristics include high on-state current densities (>1600 A/cm(2)) and current on/off ratios exceeding 800 at low temperature. Two distinct charge transport mechanisms are identified, which are dominant for different regimes of temperature and gate voltage. In particular, the Schottky barrier between graphene and BP determines charge transport at high temperatures and positive gate voltages, whereas tunneling dominates at low temperatures and negative gate voltages. These results elucidate out-of-plane electronic transport in BP and thus have implications for the design and operation of BP-based van der Waals heterostructures.


Subject(s)
Graphite , Sulfides , Transistors, Electronic , Transition Elements
19.
Adv Mater ; 27(48): 8017-22, 2015 Dec 22.
Article in English | MEDLINE | ID: mdl-26516073

ABSTRACT

The anisotropic thermal conductivity of passivated black phosphorus (BP), a reactive two-dimensional material with strong in-plane anisotropy, is ascertained. The room-temperature thermal conductivity for three crystalline axes of exfoliated BP is measured by time-domain thermo-reflectance. The thermal conductivity along the zigzag direction is ≈2.5 times higher than that of the armchair direction.


Subject(s)
Phosphorus/chemistry , Thermal Conductivity , Anisotropy , Models, Molecular , Molecular Conformation , Pressure , Temperature
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