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We analyzed protein expression in the cytosolic fraction prepared from whole lung tissue in male Swiss-Webster mice exposed 1 h/day for seven days to aerosolized JP-8 jet fuel at concentrations of 1000 and 2500 mg/m3, simulating military occupational exposure. Lung cytosol samples were solubilized and separated via large scale, high resolution two-dimensional electrophoresis (2-DE) and gel patterns scanned, digitized and processed for statistical analysis. Significant quantitative and qualitative changes in tissue cytosol proteins resulted from jet fuel exposure. Several of the altered proteins were identified by peptide mass fingerprinting, confirmed by sequence tag analysis, and related to impaired protein synthetic machinery, toxic/metabolic stress and detoxification systems, ultrastructural damage, and functional responses to CO2 handling, acid-base homeostasis and fluid secretion. These results demonstrate a significant but comparatively moderate JP-8 effect on protein expression and corroborate previous morphological and biochemical evidence. Further molecular marker development and mechanistic inferences from these observations await proteomic analysis of whole tissue homogenates and other cell compartment, i.e., mitochondria, microsomes, and nuclei of lung and other targets.

Lead is a potent neuro- and nephrotoxin in humans and a renal carcinogen in rats. Previous studies have detected lead-induced increases in the activities of specific detoxification enzymes in distinct kidney cell types preceding irreversible renal damage. While preferential susceptibility of the highly vascularized cortex to the effects of lead is clear, lead effects on the medullary region have remained unexplored. The present study was undertaken to investigate the extent to which regional renal protein expression differs and to determine which, if any, regionally distinct protein markers indicative of lead's renotoxic mechanism might be detected in kidney cortical and medullary cytosols. We examined protein expression in these two functionally and anatomically distinct regions, and identified several proteins that are differentially expressed in those regions and were significantly altered by lead. Kidney cytosols from rats injected with lead acetate (114 mg/kg, three consecutive daily injections) were separated by two-dimensional electrophoresis. Lead exposure significantly (P

Glutathione S-transferases (GST) are a family of detoxification isoenzymes that catalyze the conjugation of xenobiotics and their metabolites with reduced glutathione. Lead exposure in rats is known to induce GST isoenzymes in the liver and kidney. These changes in expression have potential use as biomarkers of lead exposure. Because two-dimensional electrophoresis (2-DE) enables one to analyze both protein abundance changes and chemical changes in protein structure, 2-DE was used to determine the effect of in vivo lead exposure on GST isoform expression in rat kidney cytosols. Male Sprague-Dawley rats were exposed to inorganic lead, and proteins were separated by conventional ISO-DALT and NEPHGE-DALT techniques and blotted for immunological identification. Lead exposure caused detectable inductions in both GSTP1 and GSTM1 and quantifiable charge modification in GSTP1. These preliminary data confirm the utility of 2-D electrophoretic GST analysis as indicative of lead exposure and toxicity and support its use for further elaboration of lead's effects on renal protein expression.

This article describes the utility of Spizizen medium in effecting the release of 2,4 dinitrotoluene (DNT) from plasticized propellant in aged clay soil and of added Pseudomonas organisms in enhancing the rate of degradation of DNT in clay and sandy soils. DNT is an environmental problem because of its toxicity to mammals. It is proposed that the citrate in Spizizen medium chelates metals that form the aggregates of humin in aged clay soils, thereby releasing propellant components. Lack of awareness of DNT mobilization by citrate or other polyanions may lead to a potential underestimation of the 2,4 DNT present in aged contaminated soil and a potential increased release of DNT following exposure to solvents containing citrate or other polyanions. DNT in contaminated sandy soils was rapidly degraded when Pseudomonas and Spizizen medium were added (85% degraded in 20 days). Pseudomonas isolated/Torn soils at the Badger Plant have particular utility for the in situ degradation of 2,4 DNT in clay and sandy soils because they metabolize Spizizen medium, thrive in diverse climates, and have been selected for their ability to grow in soils contaminated with DNT. Mixture of either the contaminated clay soil or the contaminated sandy soil with uncontaminated prairie silt loam (20:80 ratio) facilitated management of the treatment process. This observation is important because of the widespread distribution, and hence low cost, of this soil type in the central United States.

This report describes the morphological changes observed in the brain of an untreated 27-year-old man with phenylketonuria, cortical blindness, and seizures. Golgi-Kopsch silver, cresyl violet, and hematoxylin and eosin stains were used to study cell structure and organization of the cerebellum, the lateral geniculate nuclei, the visual cortex, frontal cortex, and hippocampus. Extensive neuronal losses occurred in the right lateral geniculate nucleus (LGN), the visual cortex, and hippocampus. The left LGN, cerebellum, and frontal cortex retained neuronal components; there was a reduction in the number of dendritic processes on the Purkinje cells of the PKU subject. The loss of neurons in the LGN and occipital cortex is related to the blindness and the neuronal loss in the hippocampus is related to seizure activity.

We used Western blot analysis to examine the occurrence and titer of antibody to cytoskeletal neurofilament protein antigens in patients with neuropsychiatric manifestations of systemic lupus erythematosus (SLE) and in controls. Twenty-two patients with neuropsychiatric SLE (NPSLE) had an increased incidence of antineurofilament antibody (ANFA) compared with 34 patients with SLE without neuropsychiatric symptoms, 78 patients with other disease processes, and 22 healthy controls. ANFA were found to be directed against the 205,000- and 160,000-dalton proteins of the neurofilament triplet. Patients with a diffuse NPSLE clinical presentation had the greatest frequency of serum ANFA (7 of 12, 58%) compared with all other groups examined. Magnetic resonance imaging and serum anticardiolipin antibody testing were also performed in selected patients with NPSLE. Patients with a focal clinical presentation of NPSLE, positive magnetic resonance imaging findings, and negative serum ANFA had significantly elevated levels of anticardiolipin antibody.

– The buoyant density, ultrastructure and protein composition of dendrodendritic (DD), axodendritic (AD) and axosomatic (AS) synaptosomes were compared. DD synaptosomes prepared from either bovine superior colliculi or olfactory bulbs sedimented in 0.32 m-sucrose at 1000 g whereas AD and AS synaptosomes from frontal and temporal lobe cortices sedimented at 10.000 g. In gradients of Renografin the DD contacts banded at a density of 1.12 whereas AD and AS banded at 1.07. The DD contacts appeared as large clusters of serial contacts, and each individual terminal had a mean surface area of 1.48 μm2; the mean area of AD and AS terminals was less than 0.35 μm2. The protein compositions of DD, AD and AS synaptosomes were quite similar, with minor exceptions. These findings suggest that different synaptosmal types evolved from common membrane constituents.

This report describes a patient with small-cell carcinoma of the lung associated with blindness. The serum of this patient was tested for immunoreactivity with retinal sections because there was no evidence of tumor metastasis to the central nervous system and because neuroendocrine cells of the lung share common antigens with retinal neurons. The immunoglobulins in the sera from this patient, from two other patients with small-cell carcinoma, from two patients with multiple sclerosis and from three controls were reacted with 8 micrometers thick sections of retina. Dog, cat and human retinal sections were used. Antihuman immunoglobulins that were conjugated to horseradish peroxidase were used as the second antibody to identify the cells which bound the patients' immunoglobulins. A high titer (1:500) antibody level against retinal ganglion cells was found in the patient with small-cell carcinoma and blindness; the antibody reaction was similar with retina from the three species. The large ganglion cells bound the immunoglobulins of the patients with small-cell carcinoma and blindness while the immunoglobulins from the control and multiple sclerosis subjects did not bind these cells selectively at high dilutions. It remains to be shown whether these antibodies have an etiologic significance in the development of blindness.

The protein compositions of subcellular fractions of muscle obtained from 17 Duchenne dystrophy patients, 15 disease controls (10 different primary myopathies, 5 spinal muscular atrophy patients), and 10 normals were examined by polyacrylamide gel electrophoresis. The gels were stained with Coomassie Brilliant Blue and with “Stains-all,” which stains calcium-binding proteins, sialic acid-rich glycoproteins, and phosphoproteins. In muscle membrane fractions of Duchenne dystrophy patients there was a marked reduction in the concentrations of calsequestrin and a 39 kDa protein that stained blue with “Stains-all.” There were changes in the proteins of all sub-cellular fractions of Duchenne's patients; some of these changes appear to be specific for Duchenne dystrophy (DD). There was no apparent correlation between the protein changes observed on acrylamide gels and the age of the patients, the duration of the disease, the degree of disability, or activity of creatine kinase. A decreased level of calsequestrin in DD sarcoplasmic reticulum may contribute to an increased level of free calcium seen in muscle from these patients.

Recently, patients with visual paraneoplastic syndrome (VPS) were described, a binocular loss of vision found in patients with small cell carcinoma of the lung (SCCL). The patients have serum antibodies against a small number of discrete antigens which are shared by the retina and small cell carcinoma cells, and which are associated with cells and processes of the ganglion cell layer of the retina. Pathologic findings are presented with regard to the presence of immunoglobulins in, and the nature of the lesions in, the central nervous system of a VPS patient. The patient's blood-brain barrier was shown to be compromised, as demonstrated by the finding of high immunoglobulin levels in the cerebrospinal fluid and immune deposits in the retina. It is further shown that within the central nervous system only the retina and optic nerve show any tissue damage with the specific loss of retinal ganglion cells and their processes. The findings support the hypothesis of an autoimmune cause for this remote effect of cancer.

The fine structure of the cerebellar cortex of the macaque fetus was examined at 75, 100, 125, 150, and 175 days after conception. Young Purkinje cells were recognizable in the 75 and 100-day old fetuses, occurring in clusters several layers deep. The rough endoplasmic reticulum in the Purkinje cells was limited to the perinuclear area and the region of apical cytoplasm adjacent to the plasmalemma. Neither dendritic processes nor synaptic contacts were seen on Purkinje cells at this time, although an occasional observation was made of synapses involving other cell types. Between 100 and 125 days, the cerebellar cortex matured rapidly. At the latter time, the Purkinje cells had a well developed dendrite, and axodendritic and axosomatic synapses were seen. At 150 days gestation age the Purkinje cells had well developed Nissl substance, and the axodendritic synapses were similar in structure to the adult spine contact. The relationship between maturation of the thyroid gland and of the cerebellum in the macaque is discussed.

— A highly purified basic protein prepared from pig brain was studied by circular dichroism and viscometry. The circular dichroism spectrum of the protein in 50% (v/v) aqueous n-propanol showed two negative bands (at 217-220 nm and 204 nm); the spectrum in 90% (v/v) aqueous trifluoroethanol similarly showed two negative bands (at 217 nm and at 206 nm). The molar ellipticity of this protein in aqueous solvents was relatively flat and no negative bands were observed above 200 nm. The ηap C of the protein from pig brain was 0-12 as C O in tris buffer (0-1 M, pH 7-8). On the basis of these studies we concluded that the protein is asymmetric and extended in aqueous systems and contains a maximum of 20 per cent α-helix in trifluoroethanol.

Intact synaptic complexes were isolated from five human cerebral cortices obtained 4–20 hr after death. Synaptic complexes had a common isopycnic banding density of 1.17–1.20 in CsCl. Their banding densities and ultrastructural features were similar to those of complexes isolated from a variety of other mammalian species. The ultrastructure of the synaptic complexes isolated from different aged subjects (2, 3, 28, 76, and 78 years old) were similar.