Jack Hall

Changes in lung permeability correlate with lung histology in a chronic exposure model.

In a simulated military flight-line exposure protocol, the effects of JP-8 jet fuel exposure on lung epithelial permeability were evaluated in male Fischer 344 rats (F344). Exposures were nose-only and for one hour daily. Groups were exposed for 7, 28, and 56 days. A protocol for administering a low dose (500mg/m3/hr) and a high dose (813-1094mg/m 3 /hr) of JP-8 jet fuel was used. Longitudinal sham-exposure groups (no jet fuel) for 7, 28, and 56 days were included in the protocol. Lung epithelial permeability was measured by clearance of technetium-labeled diethylenetriamine pentaacetate (99mTcDTPA, molecular weight = 492 daltons, physical half-life = 6.02 hours). The percent clearance of 99mTcDTPA per minute was calculated. Alveolar epithelial clearance for JP-8-exposed rats was dependent on both exposure concentration and duration. It was noted that at low-dose exposure concentrations alveolar epithelial clearance of 99mTcDTPA returned to low levels (LD56 = 1.09% per min; LC56 = 0.98% per min), suggesting recovery as evidenced by microscopic exam. The corresponding 56-day high-dose group (n = 10) had a significantly higher (p < 0.05) value of 2.25% per minute. The 28-day low-dose (n = 15) and high-dose (n = 20) groups had clearance values that were significantly increased from their longitudinal control group (n = 17). The alveolar epithelial permeability values were 2.51, 1.95, and 1.20, respectively. The seven-day longitudinal control, low-dose, and high-dose groups had alveolar permeability values of 1.57, 2.16, and 2.07, respectively. The lung histology correlated

Perfect complexes on algebraic stacks

Goran Gustafsson Foundation; Australian Research Council [DE150101799]; Swedish Research Council [2011-5599, 2015-05554]

Algebraic Groups and Compact Generation of their Derived Categories of Representations

Let k be a field. We characterize the group schemes G over k, not necessarily affine, such that D-qc (B(k)G) is compactly generated. We also describe the algebraic stacks that have finite cohomological dimension in terms of their stabilizer groups.

The Hilbert stack

Let π : X → S be a morphism of algebraic stacks that is locally of finite presentation with affine stabilizers. We prove that there is an algebraic S-stack-the Hilbert stack-parameterizing proper a ...

General Hilbert stacks and Quot schemes

We prove the algebraicity of the Hilbert functor, the Hilbert stack, the Quot functor, and the stack of coherent sheaves on an algebraic stack X with (quasi-)finite diagonal without any finiteness ...

Splenic salvage quantified by uptake of heat-damaged radiolabeled red blood cells. Experimental and clinical studies

We evaluated a noninvasive radionuclide technique to quantify splenic trapping function, which is a key step in the disposition of blood-borne particulates such as poorly opsonized encapsulated microorganisms implicated in hyposplenic fulminant sepsis. Using computerized external gamma imaging, the percentage of splenic uptake of heat-damaged radiolabeled red blood cells was determined in adult Sprague-Dawley rats with eutopic (partial splenectomy) or ectopic (single or multiple autotransplantation) remnants or whole spleens, and in 14 patients with either an intact spleen or splenic remnants after treatment for trauma or hypersplenism. The masses of both eutopic and ectopic remnants correlated directly with the percentage of heat-damaged red blood cell uptake, but the percentage of uptake per gram was higher in eutopic remnants, paralleling more vigorous compensatory growth. In patients, the percentage of heat-damaged red blood cell uptake by remnant spleens was similar to that seen in the rats and, in addition, was supernormal in those with congestive splenomegaly. This noninvasive technique both provides a vivid biplanar image and quantifies blood-borne particle trapping, which is a key splenic function. A heat-damaged red blood cell uptake of less than 15 percent after splenic salvage suggests marginal splenic performance and continued vulnerability to overwhelming sepsis.

Cobalt‐57 bleomycin for imaging head and neck tumors

Cobalt‐57 bleomycin imaging was performed in 11 patients with a history of head and neck cancer. Clinical and scan findings concurred on the presence and extent of tumor in 9 patients (82%); tumor was present in 7 and absent in 2 of the 9. In 2 patients (18%) the scan demonstrated tumor in the neck but failed to show metastatic sites. Cobalt‐57 bleomycin images were of good technical quality, with remarkably low background activity at 24 hours after administration. Cobalt‐57 bleomycin imaging appears to be a promising technique for evaluating patients with head and neck tumors.

Pharmacokinetics of bleomycin in man: III. Bleomycin 57Co Vs Bleomycin

SummaryOf all the bleomycin-containing radiopharmaceuticals, bleomycin 57Co has proven the most useful whole-body tumor-imaging agent. We have studied its in vitro physicochemical properties and in vivo disposition in animals and man to optimize its use as a scanning agent. High-pressure liquid chromatographic analysis of the standard bleomycin 57Co preparation (1 unit bleomycin plus 1 mCi chloride 57Co showed it to contain 1% free chloride 57Co). Dialysis experiments showed that bleomycin 57Co does not dissociate as it diffuses through a dialysis membrane. In nine patients, bleomycin 57Co had a t12/βof 3.4 h, a t12/γof 45.8 h, a Vd of 12.1 liters/m2 and a 24-h urinary excretion of 82.1% of the administered dose. In comparison, bleomycin, assayed by radioimmunoassay, had a terminal phase plasma t1/2 of only 4.0 h, a similar Vd (17.3 liters/m2), and a 24-h urinary excretion of only 44.8%. Bleomycin 57Co tumorto-plasma concentration ratios ranged from 14.1–23.8 at 1 day to 5.4 at 2 days after administration. Our finding that tumor imaging with bleomycin 57Co is best achieved at 24 h is well explained by its almost complete urinary elimination in the first few hours after administration and the peak tumor-to-plasma ratio achieved at 24 h. One disadvantage of bleomycin 57Co as a scanning agent is its very extended plasma t1/2 In rabbits chloride 57Co has the same prolonged plasma terminal elimination phase (t12/γ) as our standard bleomycin 57Co preparation, which contains chloride 57Co as a 1% impurity. Removal of this impurity prior to scanning or use of cold cobalt chloride to help eliminate it from the plasma might result in a shortened bleomycin 57Co plasma t12/γ.

The Balmer spectrum of a tame stack

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[153Sm]citrate for tumor and abscess localization

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