Publications by authors named "Coffee K"

Article Synopsis
  • Understanding the thermal decomposition of TATB is crucial for ensuring safety in energetic materials research, as it involves understanding how it breaks down under heat.
  • Previous models suggested that the reaction primarily produces hydroxyl (HO), but recent mass spectrometry data showed the simultaneous release of carbon monoxide (CO) during the decomposition process.
  • The latest findings indicate that the CO results from the breakdown of the TATB ring structure rather than from impurities, which impacts current models of energy release and deflagration-to-detonation transitions in the study of decomposition.
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The influence of oceanic biological activity on sea spray aerosol composition, clouds, and climate remains poorly understood. The emission of organic material and gaseous dimethyl sulfide (DMS) from the ocean represents well-documented biogenic processes that influence particle chemistry in marine environments. However, the direct emission of particle-phase biogenic sulfur from the ocean remains largely unexplored.

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Ignition implosions on the National Ignition Facility [J. D. Lindl et al.

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Purpose: This pilot phase I trial evaluated the safety and maximum-tolerated dose of p53 gene transfer using an adenovirus vector (Ad-p53) delivered via bronchoalveolar lavage (BAL) to patients with bronchioloalveolar lung carcinoma (BAC).

Patients And Methods: Patients were initially administered two treatments of Ad-p53 to a single involved lobe, beginning at 2 x 10(9) viral particles (vp) per dose and escalated to a maximum of 2 x 10(12) vp. If a clinical benefit was seen and the treatment was well tolerated, additional doses could be administered to additional lobes.

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Actual or surrogate chemical, biological, radiological, nuclear, and explosive materials and illicit drug precursors can be rapidly detected and identified when in aerosol form by a Single-Particle Aerosol Mass Spectrometry (SPAMS) system. This entails not only the sampling of such particles but also the physical analysis and subsequent data analysis leading to a highly reliable alarm state. SPAMS hardware is briefly reviewed.

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Different particulate matter (PM) samples were investigated by on-line single-particle aerosol time-of-flight mass spectrometry (ATOFMS). The samples consist of soot particulates made by a diffusion flame soot generator (combustion aerosol standard, CAST), industrially produced soot material (printex), soot from a diesel passenger car as well as ambient particulates (urban dust (NIST) and road tunnel dust). Five different CAST soot particle samples were generated with different elemental carbon (EC) and organic carbon (OC) content.

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Bioearosol mass spectrometry (BAMS) analyzes single particles in real time from ambient air, placing strict demands on instrument sensitivity. Modeling of the BAMS reflectron time of flight (TOF) with SIMION revealed design limitations associated with ion transmission and instrument sensitivity at higher masses. Design and implementation of a BAMS linear TOF with electrostatic ion guide and delayed extraction capabilities has greatly increased the sensitivity and mass range relative to the reflectron design.

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Bioaerosol mass spectrometry (BAMS) performs single-cell analysis in real time. However, the specificity of BAMS mass signatures has been limited by low sensitivity at high masses. To increase the mass range and sensitivity of BAMS, a novel design was developed that utilizes a linear flight tube with delayed extraction and an electrostatic ion guide.

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The mda-7 gene (approved gene symbol IL24) is a novel tumor suppressor gene with tumor-apoptotic and immune-activating properties. We completed a Phase I dose-escalation clinical trial, in which a nonreplicating adenoviral construct expressing the mda-7 transgene (INGN 241; Ad-mda7) was administered intratumorally to 22 patients with advanced cancer. Excised tumors were evaluated for vector-specific DNA and RNA, transgenic MDA-7 expression, and biological effects.

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The melanoma differentiation-associated gene-7 (mda-7; approved gene symbol IL24) is a tumor suppressor gene whose expression induces selective apoptosis in tumor cells. To characterize the safety and biologic activity of mda-7 gene transfer, we conducted a phase I trial using intratumoral injections of an adenovirus containing the mda-7 construct (Ad-mda7; INGN 241; 2 x 10(10) to 2 x 10(12) vp) in 28 patients with resectable solid tumors. One hundred percent of injected lesions demonstrated INGN 241 vector transduction, transgenic mRNA, elevated MDA-7 protein, and apoptosis induction, with the highest levels near the injection site.

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The rapid chemical analysis of individual cells is an analytical capability that will profoundly impact many fields including bioaerosol detection for biodefense and cellular diagnostics for clinical medicine. This article describes a mass spectrometry-based analytical technique for the real-time and reagentless characterization of individual airborne cells without sample preparation. We characterize the mass spectral signature of individual Bacillus spores and demonstrate the ability to distinguish two Bacillus spore species, B.

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The continuous growth of tumors depends on the altered regulation of the cell cycle, which is in turn modulated by signals from growth factors and their receptors. Blockade of insulin-like growth factor (IGF)-I and IGF-IR by antisense or dominant negative plasmid transfection can suppress tumorigenicity and induce regression of established tumors. We have constructed two recombinant adenoviruses: an adenovirus expressing truncated IGF-IR (ad-IGF-IR/950) with an engineered stop codon at amino acid residue 950, and an adenovirus expressing the soluble extracellular domain of IGF-IR (ad-IGF-IR/482) with an engineered stop codon at amino acid residue 482.

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Background & Aims: Insulin-like growth factor (IGF)-I receptor (IGF-Ir) signaling is required for maintenance of growth and tumorigenicity of several tumor types. We have previously shown successful therapy in a lung cancer xenograft model using an adenovirus expressing antisense IGF-Ir. In this study, we sought to better dissect the mechanism and develop potentially more effective IGF-Ir-targeted therapeutics by developing and testing tetracycline-regulated and recombinant adenoviruses expressing dominant negative receptors.

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We studied the effect of T cells on IL-18 production by human monocytes in response to Mycobacterium tuberculosis. Addition of activated T cells markedly enhanced IL-18 production by monocytes exposed to M. tuberculosis.

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Prostaglandins (PGs) are ubiquitous lipid mediators derived from cyclooxygenase metabolism of arachidonic acid that exert a broad range of physiologic activities, including modulation of inflammation, ovulation and arterial blood pressure. PGE2, a chief cyclooxygenase product, modulates blood pressure and fertility, although the specific G protein-coupled receptors mediating these effects remain poorly defined. To evaluate the physiologic role of the PGE2 EP2 receptor subtype, we created mice with targeted disruption of this gene (EP2-/-).

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Hypertension, hypercholesterolemia, atherosclerosis, and coronary heart disease are associated with abnormal endothelium-dependent, nitric oxide-mediated vasorelaxation. In rats, hypercholesterolemia in combination with deficiencies of vitamin E and selenium results in increased endogenous lipid oxidation and endothelial dysfunction. Two hydroxymetabolites of doxazosin, an alpha 1-adrenergic blocking antihypertensive agent, inhibit human lipid oxidation in vitro in a dose-dependent fashion.

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Background: Pharmacological control of hypertension has contributed to a significant decrease in cardiovascular morbidity and mortality, although the beneficial effect on cardiac and renal diseases has been far more modest than the reduction in stroke. The endothelium plays a crucial homeostatic role in the regulation of vascular tone thrombogenesis and vascular remodeling. We studied the relationship between endothelial dysfunction and cardiorenal injury in hypertensive rats and evaluated the effects of two classes of antihypertensive agents commonly used in the clinical setting, a diuretic (DIU) and an ACE inhibitor (CEI).

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Abnormal regulation of local vascular tone occurs early in human and experimental atherosclerosis. Impaired endothelium-dependent vascular relaxations mediated by endothelium-derived relaxing factor are an important contributor to these abnormalities. Endothelium-derived relaxing factor is nitric oxide released as such or attached to a carrier molecule.

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Previous studies have suggested that guanine nucleotide regulatory (G) proteins modulate endotoxin-stimulated peritoneal macrophage arachidonic acid (AA) metabolism. Endotoxin-stimulated metabolism of AA by peritoneal macrophages is decreased in endotoxin tolerance (Rogers et al. Prostaglandins 31: 639-650, 1986).

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The mechanisms whereby bacterial endotoxins stimulate arachidonic acid metabolism in macrophages are uncertain. Both protein kinase C activation and de novo protein synthesis occur in macrophages in response to endotoxin. In this study we evaluated the time course and role of protein kinase C and de novo protein synthesis in endotoxin stimulated arachidonic acid metabolism in resident rat peritoneal macrophages.

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Repeated sublethal doses of endotoxin render rats tolerant to lethal doses of endotoxin and reduce thromboxane (Tx) A2 synthesis. Endotoxin-tolerant rats are also more resistant to lethal doses of U46619, a stable TxA2 mimetic. These observations raised the possibility that tolerance may alter hemodynamic responses to TxA2 via one or more mechanisms.

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The effects of cholera toxin or pertussis toxin and nonhydrolyzable GTP analogs on Salmonella enteritidis endotoxin stimulation of iTxB2 and i6-keto-PGF1 alpha synthesis in control and endotoxin tolerant rat peritoneal macrophages were determined. Pretreatment with pertussis toxin alone had no effect on basal macrophage iTxB2 or i6-keto-PGF1 alpha production, but pertussis toxin (0.1, 1.

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