Our previous studies found that experimental infection of BALB/c mice with the Gram-positive bacterium Nocardia asteroides induced a parkinsonian-type syndrome with levodopa-responsive movement abnormalities, loss of nigrostriatal dopaminergic neurons, depletion of striatal dopamine, and intraneuronal inclusions in the substantia nigra (SN) with an appearance similar to Lewy bodies. In the present study, an in situ hybridization technique was developed to detect nocardial 16S ribosomal RNA (rRNA), using a Nocardia-specific probe (B77). Cerebral cortical specimens from cynomolgus monkeys were examined for the presence of nocardial RNA 48 h, 3.
View Article and Find Full Text PDFThe authors will demonstrate Quill (QUestions and Information Logically Linked), a comprehensive structured reporting environment for ambulatory care that was developed at the Vanderbilt University Medical Center. A notes capture tool was sought with the immediate hope of decreasing or eliminating transcription costs (currently around $6M/yr) and paper based processing while providing a foundation for decision support and research in the future.
View Article and Find Full Text PDFMany cellular processes are regulated by reversible protein phosphorylation, and the ability to broadly identify and quantify phosphoproteins from proteomes would provide a basis for gaining a better understanding of these dynamic cellular processes. However, such a sensitive, efficient, and global method capable of addressing the phosphoproteome has yet to be developed. Here we describe an improved stable-isotope labeling method using a phosphoprotein isotope-coded solid-phase tag (PhIST) for isolating and measuring the relative abundances of phosphorylated peptides from complex peptide mixtures resulting from the enzymatic digestion of extracted proteins.
View Article and Find Full Text PDFUltrasensitive nanoscale proteomics approaches for characterizing proteins from complex proteomic samples of <50 ng of total mass are described. Protein identifications from 0.5 pg of whole proteome extracts were enabled by ultrahigh sensitivity (<75 zmol for individual proteins) achieved using high-efficiency (peak capacities of approximately 10(3)) 15-microm-i.
View Article and Find Full Text PDFEfforts to develop a liquid chromatography (LC)/mass spectrometry (MS) technology for ultra-sensitive proteomics studies (i.e., nanoscale proteomics) are described.
View Article and Find Full Text PDFCryogenic burns are uncommon. We present two patients who presented to a Regional Burns Unit on consecutive days with almost identical burn injuries caused by exposure to a unique source of sub-zero temperature, the spray from an aerosol deodorant. The clinical features and management of the cases are outlined, and we discuss the mechanism of a cryogenic burn.
View Article and Find Full Text PDFExperimental infection of BALB/c mice with the gram-positive bacterium Nocardia asteroides produces marked loss of nigrostriatal dopamine neurons, resulting in striatal dopamine depletion. To investigate the mechanism(s) responsible for this neuronal loss, we evaluated the influence of N. asteroides cell-free culture filtrates on rat pheochromocytoma PC12 cells, an in vitro model for dopamine neurons.
View Article and Find Full Text PDFCharacterization of the surface exposed membrane subproteome of human mammary epithelial cells (strain 184 A1L5) implemented lysine specific in situ labeling of the proteins using sulfosuccinimidyl-6-(biotinamido)hexanoate, followed by enrichment of the biotinylated, tryptically digested peptides, and then liquid chromatography-tandem mass spectrometry analysis of the labeled peptides. Probing the membrane subproteome in this manner yielded unambiguous identification of proteins situated on the cell surface. The method reported can be adapted to include stable isotope labeling of proteins for quantitation of changes occurring on the cell surface in response to specific perturbations.
View Article and Find Full Text PDFA method for the complete peptide mapping of the model integral membrane protein bacteri-orhodopsin is demonstrated. Utilizing more effective enzymatic digestion, procedures with capillary liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and tandem mass spectrometry (MS/MS), all predicted tryptic digestion products were detected, as well as peptides from all previously reported post-translational modifications of bacteriorhodopsin. A significant contribution of chymotryptic-like digestion products was also observed.
View Article and Find Full Text PDFIt is often assumed that membership in a stigmatized group has negative consequences for the self-concept. However, this relationship is neither straightforward nor inevitable, and there is evidence suggesting that negative consequences may not necessarily occur (Psychol. Rev.
View Article and Find Full Text PDFSeveral gibberellins in which the 16-methyl group of the 16-epimers of dihydro-GA(5) had been replaced by ethyl, n-propyl and n-butyl were prepared and tested at doses of 1, 5 or 25&mgr;g per plant for their effects on stem growth and flowering of the grass Lolium temulentum. The ethyl and n-propyl derivatives were most inhibitory of elongation, the exo-isomers being more active than the endo-forms. While both isomers of dihydro-GA(5) promoted flowering, among the 17-alkyl analogues, only the exo-ethyl derivative showed significant activity.
View Article and Find Full Text PDFJ Child Neurol
February 2001
A 29-week premature infant with severe central hypoventilation secondary to Prader-Willi syndrome required mechanical ventilation until 55 days of age. This disorder must be considered in the differential diagnosis of a premature infant who does not have primary lung disease but has significant hypotonia because the respiratory failure may require prolonged supportive care.
View Article and Find Full Text PDFCrit Care Nurs Clin North Am
March 2000
Since its approval by the USFDA in 1998, the LVAD has been used primarily as a bridge to transplantation. It has been effective in improving the overall health and debilitated states in patients with cardiomyopathies and CHF by restoring them to a near normal hemodynamic state and improving end-organ blood flow. Recent studies indicate that the LVAD might be useful as a destination therapy, making transplantation unnecessary, providing one solution to the imbalance of heart donor supply to transplant candidate need.
View Article and Find Full Text PDFStudies with cerebrospinal fluid from subjects with Parkinson's disease suggest that purine abnormalities may be present in this disorder. The effects of purines on dopamine metabolism have not been characterized, though adenosine is known to inhibit dopaminergic neurotransmission. In this study, dopamine, its precursor 3,4-dihydroxyphenylalanine (DOPA), and its degradation products 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) were measured in rat pheochromocytoma PC12 cells following 24-h incubation with 5, 50, and 500 microM adenosine, adenine, guanosine, guanine, hypoxanthine, xanthine, and uric acid.
View Article and Find Full Text PDFThe debate about the toxicity of L-DOPA to dopaminergic neurons has not been resolved. Even though enzymatic and nonenzymatic metabolism of L-DOPA can produce hydrogen peroxide and oxygen free radicals, there has been controversy as to whether L-DOPA generates an oxidant stress in vivo. This study determined whether acute or repeated administration of L-DOPA caused in vivo production of hydroxyl radicals in striatum and other brain regions in rats with a unilateral 6-hydroxydopamine lesion of the dopaminergic nigrostriatal projections.
View Article and Find Full Text PDFLevodopa treatment in Parkinson's disease has been suggested to contribute to disease progression through free radical generation. We compared the time course of levodopa-induced dopamine metabolism, and the resulting oxidative stress, between rat brain regions with varying dopaminergic innervation. At 1, 4, 8, and 12 h after levodopa administration (100 mg/kg), dopamine, dihydroxyphenylacetic acid, and homovanillic acid were measured in striatum and ventral midbrain, regions containing marked dopaminergic innervation, and in prefrontal cortex and cerebellum, which possess little dopaminergic innervation.
View Article and Find Full Text PDFBioorg Med Chem Lett
March 1998
Tethering the N6-substituents of N6-substituted adenosines to N1 has resulted in a series of conformationally restricted adenosine analogues. The resultant diimidazo[1,2-c:4',5'-e]pyrimidines were shown to be adenosine A1 selective.
View Article and Find Full Text PDFSilicon-based microphysiometry, measuring extracellular acidification rate of cells in culture, demonstrated that a series of diimidazo[1,2-c:4',5'-e]pyrimidines were agonists at the human adenosine A1 receptor. 5-amino-7,8-dihydro-3-ribofuranose-8-(R)-(phenyl)-3H-diimidazo [1,2-c:4',5'-e]pyrimidine (2a) had an EC50 of 100 microM and reached 90% of the Emax produced by R-PIA.
View Article and Find Full Text PDFParkinson's disease (PD) is characterized by decreased striatal dopamine, but serotonin (5-HT) is also reduced. Because 5-HT decreases following a single levodopa injection, levodopa has been suggested to contribute to PD's serotonergic deficits. However, in a recent study, rat striatal serotonin levels were reported to increase following 15-day levodopa administration.
View Article and Find Full Text PDFThe significance of guanine nucleotides and nucleosides in neurodegenerative disorders is suggested by recent reports that these molecules enhance neurite branching and astrocyte proliferation. The objective of this study was to investigate the influence of increased dopamine metabolism, produced by 5-day treatment of rabbits with reserpine (2 mg/kg) or levodopa (LD) (50 mg/kg), on striatal concentrations of guanosine, guanine, and their metabolites. Reserpine treatment decreased striatal guanosine by 41% and increased guanine by 50%, while LD decreased guanosine by 48% (all p < 0.
View Article and Find Full Text PDF