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McGraw, M.

Publications and source records attributed to McGraw, M..

23 records · Page 2Linked to original sources

Chemical constituents involved in e-cigarette, or vaping product use-associated lung injury (EVALI)

BackgroundThe Centers for Disease Control (CDC) declared e-cigarette (e-cig), or vaping product use-associated lung injury (EVALI) a national outbreak due to the high incidence of emergency department admissions and deaths. Investigators have identified vitamin E acetate (VEA) as the plausible cause for EVALI, based on compounds found in bronchoalveolar lavage fluid. ObjectivesWe defined the chemical constituents present in e-cig cartridges associated with EVALI and compared constituents to medical-grade and cannabidiol (CBD) containing cartridges. MethodsWe measured chemicals and elemental metals in e-liquid and vapor phases of e-cig counterfeit cartridges by Gas Chromatography (GC) and Mass Spectrometry (MS), EPA method TO-15 by GCMS, and ICP-MS analysis. ResultsWe have identified chemical constituents in e-cig vaping tetrahydrocannabinol (THC)-containing counterfeit cartridges compared to medical-grade and cannabidiol (CBD) containing cartridges. Apart from VEA and THC, other potential toxicants correlated with EVALI included solvent-derived hydrocarbons, silicon conjugated compounds, various terpenes, pesticides/plasticizers/polycaprolactones, and metals. These chemicals are known to cause symptoms, such as cough, shortness of breath or chest pain, nausea, vomiting or diarrhea, fatigue, fever, or weight loss, all symptoms presenting in patients with EVALI. ConclusionThis study provides insights into understanding the chemical-induced disease mechanism of acute lung injury.

pharmacology and toxicology↗

Metronomic capecitabine as an immune modulator in glioblastoma patients reduces myeloid-derived suppressor cells

BackgroundMyeloid-derived suppressor cells (MDSCs) are elevated in glioblastoma (GBM) patient circulation, present in tumor tissue, and associated with poor prognosis. While low-dose chemotherapy reduces MDSCs in preclinical models, the use of this strategy to reduce MDSCs in GBM patients has yet to be evaluated. MethodsA phase 0/1 dose-escalation clinical trial was conducted in recurrent glioblastoma patients treated 5-7 days prior to surgery with low-dose chemotherapy via capecitabine followed by concomitant low-dose capecitabine and bevacizumab. Clinical outcomes, including progression-free and overall survival, were measured, along with safety and toxicity profiles. Over the treatment time course, circulating MDSC levels were measured by multi-parameter flow cytometry, and tumor tissue immune profiles were assessed via mass cytometry time-of-flight. ResultsA total of 11 patients were enrolled across escalating dose cohorts of 150, 300, and 450 mg bid, with a progression-free survival of 5.8 months (range of 1.8-27.8 months) and an overall survival of 11.5 months (range of 3->28.0 months) from trial enrollment. No serious adverse events related to the drug combination were observed. Compared to pre-treatment baseline, circulating MDSCs were found to be higher after surgery in the 150 mg treatment arm and lower in the 300 mg and 450 mg treatment arms. Increased cytotoxic immune infiltration was observed after low-dose capecitabine compared to untreated GBM patients in the 300 mg and 450 mg treatment arms. ConclusionsLow-dose, metronomic capecitabine in combination with bevacizumab is well tolerated in GBM patients and was associated with a reduction in circulating MDSC levels and an increase in cytotoxic immune infiltration into the tumor microenvironment. Trial registrationNCT02669173 FundingThis research was funded by the Cleveland Clinic, Case Comprehensive Cancer Center, Musella Foundation, and B*CURED. Capecitabine was provided in kind by Mylan Pharmaceuticals.

clinical trials↗

Conserved cell types with divergent features between human and mouse cortex

Elucidating the cellular architecture of the human neocortex is central to understanding our cognitive abilities and susceptibility to disease. Here we applied single nucleus RNA-sequencing to perform a comprehensive analysis of cell types in the middle temporal gyrus of human cerebral cortex. We identify a highly diverse set of excitatory and inhibitory neuronal types that are mostly sparse, with excitatory types being less layer-restricted than expected. Comparison to a similar mouse cortex single cell RNA-sequencing dataset revealed a surprisingly well-conserved cellular architecture that enables matching of homologous types and predictions of human cell type properties. Despite this general conservation, we also find extensive differences between homologous human and mouse cell types, including dramatic alterations in proportions, laminar distributions, gene expression, and morphology. These species-specific features emphasize the importance of directly studying human brain.

neuroscience↗

Global immune fingerprinting in glioblastoma reveals immune-suppression signatures associated with prognosis

Abstract/SummaryGlioblastoma (GBM) remains uniformly lethal, and, despite a large accumulation of immune cells in the microenvironment, there is limited anti-tumor immune response, even with newly developed immune checkpoint therapies. To overcome these challenges and enhance the efficacy of immunotherapies, a comprehensive understanding of the immune system in GBM and changes during disease progression is required. Here, we integrated multi-parameter flow cytometry and mass cytometry time of flight (CyTOF) analysis of patient blood to determine changes in the immune system among tumor types and over disease progression. Utilizing multi-parameter flow cytometry analysis in a cohort of over 250 patients with brain tumors ranging from benign to malignant primary and metastatic, we found that GBM patients had a significant elevation in myeloid-derived suppressor cells (MDSCs) in blood, but not immunosuppressive T regulatory cells. We validated these findings in GBM patient tissue and found that increased numbers of MDSCs in recurrent GBM portended poor prognosis. CyTOF analysis of peripheral blood from a cohort of newly diagnosed GBM patients revealed that reduction in MDSC frequency over time is accompanied by a concomitant increase in dendritic cells and natural killer cells. This reduced MDSC profile was present in GBM patients with extended survival and was similar to that of low-grade glioma (LGG) patients. Our findings provide a rationale for developing strategies to target MDSCs, which are elevated in GBM patients and predict poor prognosis, either by directly targeting or by shifting the immune profile to induce differentiation toward the immune profile of LGGs.

cancer biology↗

A suite of transgenic driver and reporter mouse lines with enhanced brain cell type targeting and functionality

Modern genetic approaches are powerful in providing access to diverse types of neurons within the mammalian brain and greatly facilitating the study of their function. We here report a large set of driver and reporter transgenic mouse lines, including 23 new driver lines targeting a variety of cortical and subcortical cell populations and 26 new reporter lines expressing an array of molecular tools. In particular, we describe the TIGRE2.0 transgenic platform and introduce Cre-dependent reporter lines that enable optical physiology, optogenetics, and sparse labeling of genetically-defined cell populations. TIGRE2.0 reporters broke the barrier in transgene expression level of single-copy targeted-insertion transgenesis in a wide range of neuronal types, along with additional advantage of a simplified breeding strategy compared to our first-generation TIGRE lines. These novel transgenic lines greatly expand the repertoire of high-precision genetic tools available to effectively identify, monitor, and manipulate distinct cell types in the mouse brain.

neuroscience↗